[go: up one dir, main page]
More Web Proxy on the site http://driver.im/

WO2015056422A1 - Hydraulic drive system - Google Patents

Hydraulic drive system Download PDF

Info

Publication number
WO2015056422A1
WO2015056422A1 PCT/JP2014/005092 JP2014005092W WO2015056422A1 WO 2015056422 A1 WO2015056422 A1 WO 2015056422A1 JP 2014005092 W JP2014005092 W JP 2014005092W WO 2015056422 A1 WO2015056422 A1 WO 2015056422A1
Authority
WO
WIPO (PCT)
Prior art keywords
spool
turning
pressure
hydraulic
bucket
Prior art date
Application number
PCT/JP2014/005092
Other languages
French (fr)
Japanese (ja)
Inventor
哲弘 近藤
英泰 村岡
Original Assignee
川崎重工業株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 川崎重工業株式会社 filed Critical 川崎重工業株式会社
Priority to GB1606883.5A priority Critical patent/GB2534517B/en
Priority to CN201480056725.0A priority patent/CN105612358B/en
Publication of WO2015056422A1 publication Critical patent/WO2015056422A1/en

Links

Images

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/16Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
    • F15B11/17Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors using two or more pumps
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2278Hydraulic circuits
    • E02F9/2296Systems with a variable displacement pump
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2221Control of flow rate; Load sensing arrangements
    • E02F9/2232Control of flow rate; Load sensing arrangements using one or more variable displacement pumps
    • E02F9/2235Control of flow rate; Load sensing arrangements using one or more variable displacement pumps including an electronic controller
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2221Control of flow rate; Load sensing arrangements
    • E02F9/2239Control of flow rate; Load sensing arrangements using two or more pumps with cross-assistance
    • E02F9/2242Control of flow rate; Load sensing arrangements using two or more pumps with cross-assistance including an electronic controller
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2278Hydraulic circuits
    • E02F9/2282Systems using center bypass type changeover valves
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2278Hydraulic circuits
    • E02F9/2285Pilot-operated systems
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2278Hydraulic circuits
    • E02F9/2292Systems with two or more pumps
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/02Systems essentially incorporating special features for controlling the speed or actuating force of an output member
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/20Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/205Systems with pumps
    • F15B2211/2053Type of pump
    • F15B2211/20546Type of pump variable capacity
    • F15B2211/20553Type of pump variable capacity with pilot circuit, e.g. for controlling a swash plate
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/20Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/205Systems with pumps
    • F15B2211/20576Systems with pumps with multiple pumps
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/40Flow control
    • F15B2211/45Control of bleed-off flow, e.g. control of bypass flow to the return line
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/60Circuit components or control therefor
    • F15B2211/63Electronic controllers
    • F15B2211/6303Electronic controllers using input signals
    • F15B2211/6306Electronic controllers using input signals representing a pressure
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/60Circuit components or control therefor
    • F15B2211/63Electronic controllers
    • F15B2211/6303Electronic controllers using input signals
    • F15B2211/6306Electronic controllers using input signals representing a pressure
    • F15B2211/6313Electronic controllers using input signals representing a pressure the pressure being a load pressure
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/60Circuit components or control therefor
    • F15B2211/63Electronic controllers
    • F15B2211/6303Electronic controllers using input signals
    • F15B2211/6306Electronic controllers using input signals representing a pressure
    • F15B2211/6316Electronic controllers using input signals representing a pressure the pressure being a pilot pressure
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/60Circuit components or control therefor
    • F15B2211/63Electronic controllers
    • F15B2211/6303Electronic controllers using input signals
    • F15B2211/6346Electronic controllers using input signals representing a state of input means, e.g. joystick position
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/60Circuit components or control therefor
    • F15B2211/665Methods of control using electronic components
    • F15B2211/6652Control of the pressure source, e.g. control of the swash plate angle
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/70Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/71Multiple output members, e.g. multiple hydraulic motors or cylinders
    • F15B2211/7142Multiple output members, e.g. multiple hydraulic motors or cylinders the output members being arranged in multiple groups

Definitions

  • the present invention relates to a hydraulic drive system for a construction machine having a swing hydraulic motor.
  • hydraulic fluid is generally supplied from a hydraulic pump driven by an engine to various hydraulic actuators.
  • a hydraulic pump a variable displacement pump such as a swash plate pump or a swash shaft pump is used, and the flow rate of hydraulic oil discharged from the hydraulic pump is changed by changing the tilt angle of the hydraulic pump. .
  • Patent Document 1 discloses a hydraulic drive system that includes two hydraulic pumps driven by one engine and two regulators that adjust the tilt angles of the hydraulic pumps.
  • horsepower control is performed so that the total horsepower of the individual hydraulic pumps does not exceed the output of the engine.
  • Patent Document 1 the discharge pressure of the self-side hydraulic pump connected to the regulator and the discharge pressure of the counterpart hydraulic pump connected to the other regulator are led to each regulator.
  • the regulator increases the tilt angle of the self-side hydraulic pump and increases the discharge flow rate of the self-side hydraulic pump as the discharge pressure of the self-side hydraulic pump and the counterpart hydraulic pump increases. That is, the tilt angles of the two hydraulic pumps are always kept at the same angle.
  • the control pressure is guided to the both regulators from the proportional valve, and the tilt angle of both hydraulic pumps is increased as the control pressure is higher.
  • horsepower control based on the discharge pressures of the self-side hydraulic pump and the counterpart hydraulic pump is sometimes referred to as total horsepower control
  • horsepower control based on the control pressure is sometimes referred to as power shift control.
  • each regulator includes a servo cylinder connected to the self-side hydraulic pump, a spool for controlling the servo cylinder, and the self-side hydraulic pump and the counterpart hydraulic pump having higher discharge pressure and control pressure. It includes a horsepower control piston that presses the spool in a direction that increases the discharge flow rate of the hydraulic pump.
  • Patent Document 1 The hydraulic drive system disclosed in Patent Document 1 is intended for a hydraulic excavator, and hydraulic oil is supplied from one hydraulic pump to a swing hydraulic motor or the like via a control valve, and from the other hydraulic pump. The hydraulic oil is supplied to the bucket cylinder and the like through the control valve.
  • each regulator is configured to decrease the discharge flow rate of the self-side hydraulic pump as the discharge pressure and control pressure of the self-side hydraulic pump and the counterpart hydraulic pump increase.
  • the discharge flow rate of the other hydraulic pump can be increased.
  • FIG. 9A the performance characteristics of one hydraulic pump are shown by a solid line A when the same load is applied to the hydraulic pump and the other hydraulic pump, and the one-dot chain line B shows the case where the other hydraulic pump is unloaded. Show.
  • the above merits are effective, for example, in the case of single bucket operation.
  • an object of the present invention is to provide a hydraulic drive system that can suppress wasteful consumption of energy during turning acceleration during a turning single operation or a similar operation.
  • a hydraulic drive system is a hydraulic drive system for a construction machine having a swing hydraulic motor, and is driven by an engine to discharge hydraulic oil at a flow rate corresponding to a tilt angle.
  • the first hydraulic pump and the second hydraulic pump, the first multi-control valve connected to the first hydraulic pump and including a swing spool for controlling the swing hydraulic motor, and the second hydraulic pump The first multi-control valve, the first hydraulic pump and the discharge pressure and power shift pressure of the second hydraulic pump, and the first pump so that the discharge flow rate of the first pump decreases as they increase.
  • the second regulator adjusts the tilt angle of the second hydraulic pump, and the first regulator and the second regulator guide the pressure.
  • the discharge flow rate of the first hydraulic pump is reduced during a single turn operation or a similar operation, so that wasteful consumption of energy during turn acceleration can be suppressed.
  • the hydraulic drive system includes a spool operation detection line extending across the first multi-control valve and the second multi-control valve so as to pass through the monitoring spool including the turning spool, and the spool operation detection line.
  • the spool may be configured not to block the spool operation detection line even when it is operated. According to this configuration, the turning single operation can be detected with a simple configuration.
  • the hydraulic drive system includes a spool operation detection line extending over the first multi-control valve and the second multi-control valve so as to pass through a monitoring spool including the turning spool, and the turning spool.
  • the pilot pressure is detected in any one of the turning pressure detector for detecting that the pilot pressure of the pilot circuit for operating the pressure is raised and the pilot circuit for operating the monitoring spool other than the turning spool.
  • a non-turning pressure detector for detecting wherein the turning spool may be configured to shut off the spool operation detection line when operated. According to this configuration, it is possible to detect a single turning operation using a turning spool having a normal structure.
  • the construction machine is a hydraulic excavator including a bucket, an arm, and a boom.
  • the second multi-control valve includes a bucket spool and a boom spool as the monitoring spool, and the bucket spool is a bucket-out spool.
  • the spool operation detection line is configured not to be interrupted even when operated in the direction
  • the boom spool is configured not to interrupt the spool operation detection line even when operated in the boom lowering direction.
  • the hydraulic drive system includes a bucket-out pressure detector for detecting that a pilot pressure in a bucket-out line in the pilot circuit that operates the bucket spool is raised, and a pilot that operates the boom spool.
  • Boom lowering circuit A boom-lowering pressure detector for detecting the pilot pressure of the emissions stood, it may further comprise a. According to this configuration, it is possible to detect not only a turning operation but also a bucket-out operation and a boom lowering operation with a small required flow rate. This reduces wasteful energy consumption during turning acceleration during simultaneous operations of turning and boom lowering, turning and bucket out, and turning and boom lowering and bucket out. can do.
  • the construction machine is a hydraulic excavator including a bucket, an arm, and a boom
  • the hydraulic drive system includes the first multi-control valve and the second multi-control so as to pass through a monitoring spool including the turning spool.
  • a spool operation detection line extending across the valve may be further provided.
  • either the first multi-control valve or the second multi-control valve includes an arm spool as the monitoring spool, and the second multi-control valve includes a bucket spool as the monitoring spool.
  • a boom spool wherein the swing spool, the arm spool, the bucket spool, and the boom spool are configured to shut off the spool operation detection line when operated, and the swing spool
  • Each of the pilot circuits for operating the arm spool, the bucket spool, and the boom spool may be provided with a pressure detector for detecting that the pilot pressure of the pilot circuit is established.
  • FIG. 1 is an overall hydraulic circuit diagram of a hydraulic drive system according to a first embodiment of the present invention. It is a hydraulic circuit diagram from the 1st and 2nd multi-control valve in a 1st embodiment to a hydraulic actuator. It is a hydraulic-circuit figure for detecting operation other than turning in 2nd Embodiment of this invention. It is a hydraulic circuit diagram from the 1st and 2nd multi control valve in a 2nd embodiment to a hydraulic actuator.
  • FIG. 5 is an overall hydraulic circuit diagram of a hydraulic drive system according to a third embodiment of the present invention. It is a hydraulic circuit diagram from the 1st and 2nd multi-control valve in a 3rd embodiment to a hydraulic actuator.
  • FIG. 9A is a graph showing the performance characteristics of one hydraulic pump in the conventional hydraulic drive system
  • FIG. 9B is a graph showing the performance characteristics of the first hydraulic pump in the first embodiment.
  • FIG. 1 and 2 show a hydraulic drive system 1A according to a first embodiment of the present invention.
  • FIG. 1 is an overall hydraulic circuit diagram of a hydraulic drive system 1A schematically showing the internal configuration of first and second multi-control valves 4A and 4B described later, and FIG. 2 shows first and second multi-control valves.
  • FIG. 3 is a hydraulic circuit diagram from valves 4A and 4B to a hydraulic actuator.
  • the hydraulic drive system 1A is for a construction machine equipped with a swing hydraulic motor.
  • the construction machine is a hydraulic excavator.
  • the construction machine targeted by the hydraulic drive system 1A is not necessarily a hydraulic excavator, and may be a hydraulic crane, for example.
  • a self-propelled hydraulic excavator includes a traveling device, a main body including a driver's cab that swivels with respect to the traveling device, a boom that is lifted with respect to the main body, an arm that is swingably connected to a tip of the boom, A bucket that is swingably coupled to the tip. That is, the main body, the boom, the arm, and the bucket are revolving bodies that are revolved by a revolving hydraulic motor 24 described later.
  • the main body In a hydraulic excavator mounted on a ship, the main body is supported by the hull so as to be able to turn.
  • the hydraulic drive system 1A includes a swing hydraulic motor 24, a bucket cylinder 25, a boom cylinder 26, and an arm cylinder 27 as hydraulic actuators. Moreover, the hydraulic drive system 1A includes a first hydraulic pump 21 and a second hydraulic pump 22 that supply hydraulic oil to those hydraulic actuators, as shown in FIG. Hydraulic fluid is supplied from the first hydraulic pump 21 to the swing hydraulic motor 24, the boom cylinder 26, and the arm cylinder 27 via the first multi-control valve 4A, and from the second hydraulic pump 22, the second multi-control valve 4B. Hydraulic oil is supplied to the bucket cylinder 25, the boom cylinder 26, and the arm cylinder 27 via.
  • first hydraulic pump 21 is connected to the first multi-control valve 4A by the first supply line 11.
  • a first center bleed line 12 that guides hydraulic oil that has passed through the first multi-control valve 4A to the tank extends from the first multi-control valve 4A.
  • the second hydraulic pump 22 is connected to the second multi-control valve 4B by the second supply line 15.
  • a second center bleed line 16 that guides hydraulic oil that has passed through the second multi-control valve 4B to the tank extends from the second multi-control valve 4B.
  • the discharge flow rate of the first hydraulic pump 21 and the discharge flow rate of the second hydraulic pump 22 are controlled by a negative control (hereinafter referred to as “negative control”) method. That is, a throttle 13 is provided in the first center bleed line 12, and a relief valve 14 is disposed on a passage that bypasses the throttle 13. Similarly, a throttle 17 is provided in the second center bleed line 16, and a relief valve 18 is disposed on a passage that bypasses the throttle 17.
  • the relief valves 14 and 18 and the throttles 13 and 17 may be incorporated in the first multi-control valve 4A and the second multi-control valve 4B, respectively.
  • the first multi-control valve 4A and the second multi-control valve 4B are open center type valves including a plurality of spools. That is, in the multi-control valve (4A or 4B), the amount of hydraulic fluid flowing from the supply line (11 or 15) to the center bleed line (12 or 16) is not limited when all the spools are in the neutral position. When that spool is activated and moved from the neutral position, the amount of hydraulic fluid flowing from the supply line (11 or 15) to the center bleed line (12 or 16) is limited by the spool.
  • the first multi-control valve 4A includes a swing spool 41 for controlling the swing hydraulic motor 24, and the second multi-control valve 4B controls the bucket cylinder 25.
  • the bucket spool 44 is included.
  • the first multi-control valve 4A and the second multi-control valve 4B include boom spools 42 and 45 for controlling the boom cylinder 26 and arm spools 43 and 46 for controlling the arm cylinder 27, respectively.
  • the boom spool 45 of the second multi-control valve 4B operates at the first speed, and the boom spool 42 of the first multi-control valve 4A operates together with the boom spool 45 to achieve a second speed higher than the first speed. Is to do.
  • a check valve 47 is disposed on the line from the boom spool 42, which joins the head side line between the boom spool 45 and the boom cylinder 26.
  • the arm spool 44 of the first multi-control valve 4A operates at the first speed
  • the arm spool 46 of the second multi-control valve 4B operates together with the arm spool 44 to achieve a second speed higher than the first speed. Is to do. Only the boom spool 42 for the second boom speed is a 2-position spool, and the other spools are 3-position spools.
  • each of the first multi-control valve 4A and the second multi-control valve 4B has a central passage 4a that connects the supply line (11 or 15) and the center bleed line (12 or 16) across all spools.
  • a parallel passage 4b that guides hydraulic oil from the central passage 4a to each spool and a tank passage 4c that guides hydraulic oil from each spool (excluding the boom spool 42) to the tank are formed.
  • each of the first multi-control valve 4A and the second multi-control valve 4B may include a traveling spool for controlling the traveling hydraulic motor.
  • one or a plurality of option spools may be included in either one or both of the first multi-control valve 4A and the second multi-control valve 4B.
  • the turning pilot circuit 61 for operating the turning spool 41 includes a right turning line 61A and a left turning line 61B extending from the turning operation valve 51 to the turning spool 41
  • the bucket pilot circuit 63 for operating the bucket spool 44 includes: A bucket-in line 63A and a bucket-out line 63B extending from the bucket operation valve 53 to the bucket spool 44 are included.
  • the boom pilot circuit 64 that operates the boom spools 42 and 45 includes a boom raising line 64A extending from the boom operation valve 54 to the boom spools 42 and 45, and a boom lowering extending only from the boom operation valve 54 to the boom spool 45.
  • the arm pilot circuit 62 including the working line 64B and operating the arm spools 43 and 46 includes an arm-in line 62A and an arm-out line 62B extending from the arm operation valve 52 to the arm spools 43 and 46.
  • Each operation valve 51 to 54 includes an operation lever. When the operation lever is tilted, pilot pressure is generated in the pilot lines (61A to 64B) in the direction in which the operation lever in the pilot circuit (61 to 64) is tilted, and the spools (41 to 46) are operated.
  • the first hydraulic pump 21 and the second hydraulic pump 22 are driven by the engine 10 and discharge hydraulic oil at a flow rate corresponding to the tilt angle.
  • a swash plate pump whose tilt angle is defined by the angle of the swash plate 20 is employed as the first hydraulic pump 21 and the second hydraulic pump 22.
  • the first hydraulic pump 21 and the second hydraulic pump 22 may be a slant shaft pump whose tilt angle is defined by a slant shaft angle.
  • the tilt angle of the first hydraulic pump 21 is adjusted by the first regulator 3A
  • the tilt angle of the second hydraulic pump 22 is adjusted by the second regulator 3B.
  • the first regulator 3A includes a servo cylinder 31 connected to the swash plate 20 of the first hydraulic pump 21, a spool 32 for controlling the servo cylinder 31, a negative control piston 33 and a horsepower control piston for operating the spool 32. 34.
  • the small diameter side pressure receiving chamber of the servo cylinder 31 communicates with the first supply line 11.
  • the spool 32 controls the opening area of the line connecting the large diameter side pressure receiving chamber of the servo cylinder 31 and the first supply line 11 and also controls the opening area of the line connecting the large diameter side pressure receiving chamber and the tank. .
  • the servo cylinder 31 reduces the tilt angle of the first hydraulic pump 21 when the large diameter side pressure receiving chamber communicates with the first supply line 11 with a larger opening area, and the large diameter side pressure receiving chamber has a larger opening area with the tank. When communicating, the tilt of the first hydraulic pump 21 is increased.
  • the negative control piston 33 and the horsepower control piston 34 press the spool 32 in a direction in which the large-diameter pressure receiving chamber of the servo cylinder 31 communicates with the first supply line 11, that is, in a direction in which the discharge flow rate of the first hydraulic pump 21 decreases. To do.
  • the first regulator 3A is formed with a pressure receiving chamber for causing the negative control piston 33 to press the spool 32.
  • a first negative control pressure Pn1 which is a pressure upstream of the throttle 13 in the first center bleed line 12, is guided to the pressure receiving chamber of the negative control piston 33.
  • the first negative control pressure Pn1 is determined by the degree of restriction of the hydraulic oil flowing through the central passage 4a by the spool.
  • the horsepower control piston 34 decreases the discharge flow rate of the first hydraulic pump 21 in accordance with the discharge pressure Pd1 of the first hydraulic pump 21, the discharge pressure Pd2 of the second hydraulic pump 22, and the power shift pressure Ps. Is for. Specifically, three pressure receiving chambers for causing the horsepower control piston 34 to press the spool 32 are formed in the first regulator 3A. The three pressure receiving chambers of the horsepower control piston 34 are connected to the first supply line 11, the second supply line 15, and a power shift line 71A described later, respectively. A discharge pressure Pd1 of 21, a discharge pressure Pd2 of the second hydraulic pump 22, and a power shift pressure Ps are introduced.
  • the negative control piston 33 and the horsepower control piston 34 are configured so as to preferentially press the spool 32 in the direction of restricting (decreasing) the discharge flow rate of the first hydraulic pump 21.
  • the configuration of the second regulator 3B is the same as the configuration of the first regulator 3A. That is, the second regulator 3B adjusts the tilt angle of the second hydraulic pump 22 by the negative control piston 33 based on the second negative control pressure Pn2. Further, the second regulator 3B causes the horsepower control piston 34 to increase the second hydraulic pressure in accordance with the discharge pressure Pd2 of the second hydraulic pump 22, the discharge pressure Pd1 of the first hydraulic pump 21, and the power shift pressure Ps. The tilt angle of the second hydraulic pump 22 is adjusted so that the discharge flow rate of the pump 22 decreases.
  • the discharge pressure from the auxiliary pump 23 driven by the engine 10 is supplied as a primary pressure to the proportional valve 72 through the pilot pressure supply line 71.
  • the control pressure from the proportional valve 72 is output to the power shift line 71A, and a pair of branch lines from the power shift line 71A is one of the pressure receiving chambers of the horsepower control piston 34 in the first regulator 3A and the second regulator 3B. It extends to.
  • the proportional valve 72 is for setting the power shift pressure Ps guided to the first regulator 3A and the second regulator 3B.
  • the proportional valve 72 is controlled by the controller 8.
  • the controller 8 includes an arithmetic device, a storage device, and the like.
  • the controller 8 controls the proportional valve 72 so that the power shift pressure Ps increases and the discharge flow rates of the first hydraulic pump 21 and the second hydraulic pump 22 decrease when only the turning spool 41 operates. To control.
  • a configuration for the control will be described.
  • the turning pilot circuit 61 detects that the pilot pressure of the turning pilot circuit 61 (the right turning line 61A and the left turning line 61B) is raised, in other words, that the operation lever of the turning operation valve 51 is tilted.
  • a pressure detector 81 for turning is provided.
  • the turning pressure detector 81 is configured to selectively detect the pilot pressure with the higher pilot pressure among the right turning line 61A and the left turning line 61B.
  • a pressure sensor is used as the turning pressure detector 81.
  • the turning pressure detector 81 may be a pressure switch that is turned on or off when a pilot pressure is established in the turning pilot circuit 61.
  • the spool operation detection line 73 branches from the pilot pressure supply line 71.
  • the spool operation detection line 73 extends across the first multi-control valve 4A and the second multi-control valve 4B so as to pass through the monitoring spool 40, and is connected to the tank.
  • the monitoring spool 40 is the turning spool 41 of the first multi-control valve 4A, the bucket spool 44, the boom spool 45, and the arm spool 46 of the second multi-control valve 4B.
  • the order in which the spool operation detection line 73 passes through the monitoring spool 40 is not particularly limited.
  • the boom spool 42 and the arm spool 43 of the first multi-control valve 4A may be employed instead of the boom spool 45 and the arm spool 46 of the second multi-control valve 4B.
  • the option spool may be included in the monitoring spool 40.
  • the turning spool 41 is configured not to block the spool operation detection line 73 even when it is operated even when it is positioned at the neutral position (when it is moved from the neutral position).
  • the monitoring spool 40 other than the turning spool does not block the spool operation detection line 73 when positioned at the neutral position, but blocks the spool operation detection line 73 when operated (when moved from the neutral position). It is configured. That is, the spool operation detection line 73 is not blocked when only the swing operation valve 51 is operated, but is blocked when any one of the bucket operation valve 53, the boom operation valve 54, and the arm operation valve 52 is operated.
  • a throttle 74 is provided to prevent the pressure of the pilot pressure supply line 71 from excessively decreasing regardless of the operation state of each spool.
  • the spool operation detection line 73 is provided with a monitoring pressure detector 75 between the throttle 74 and the second multi-control valve 4B for detecting that the spool operation detection line 73 is blocked.
  • a pressure sensor is used as the monitoring pressure detector 75.
  • the monitoring pressure detector 75 may be a pressure switch that is turned on or off when the spool operation detection line 73 is interrupted.
  • the controller 8 controls the proportional valve 72 so that the power shift pressure Ps is increased. Thereby, the discharge flow rates of the first hydraulic pump 21 and the second hydraulic pump 22 are reduced. As a result, the amount of hydraulic oil supplied to the turning hydraulic motor 24 during turning acceleration can be suppressed, and wasteful consumption of energy can be suppressed. Note that the controller 8 may control the proportional valve 72 so that the power shift pressure Ps is restored after the acceleration period of turning has passed.
  • FIG. 9B the performance characteristic of the first hydraulic pump 21 when the power shift pressure Ps is raised is indicated by a two-dot chain line C.
  • the solid line A in the figure is the same as the solid line A in FIG. 9A when the same load is applied to both the hydraulic pumps 21 and 22 under the situation where the power shift pressure Ps is low. Shows performance characteristics. From the comparison between FIG. 9B and FIG. 9A, it can be seen that by increasing the power shift pressure Ps, an increase in the discharge flow rate of the first hydraulic pump 21 can be suppressed in the case of a single swing operation.
  • the turning pressure detector 81 is provided in the turning pilot circuit 61, the above-described effects can be obtained with an inexpensive configuration as compared with the case where the pressure detector is provided in the first supply line 11. Can do. Further, in the present embodiment, since the power shift pressure Ps is used while being superimposed on the horsepower control by the regulator, an increase in the discharge flow rate of the first hydraulic pump 21 is suppressed with simple control logic in the case of a single turning operation. Can be obtained. Furthermore, the load pressure acting on the swing hydraulic motor 24 decreases as it proceeds to the second half of the swing acceleration, and a large flow rate is required to increase the swing speed. In this embodiment, however, the power shift pressure Ps causes the flow rate to increase.
  • the discharge flow rate of the first hydraulic pump 21 during the turning single operation is temporarily reduced, in the latter half of the turning acceleration, as the discharge pressure Pd1 of the first hydraulic pump 21 decreases, the horsepower control action by the regulator described above is performed. As a result, the discharge flow rate of the first hydraulic pump 21 automatically increases. As a result, the hydraulic hydraulic motor 24 is supplied with a sufficient amount of hydraulic oil corresponding to the load at each turning stage, so that the feeling of operation during turning is not impaired.
  • the turning operation valve is provided only by providing a pressure detector in the turning pilot circuit 61 and the spool operation detecting line 73. It can be detected that only 51 has been operated. That is, it is possible to detect a single turning operation with a simple configuration.
  • the spool operation detection line 73 does not necessarily pass through the turning spool 41, and the number of ports for the turning spool 41 may be six. In this case, the spool operation detection line 73 may be provided only in the second multi-control valve 4B.
  • the spool operation detection line 73 is cut off. That is, the spool operation detection line 73 is shut off regardless of which of the swing operation valve 51, the bucket operation valve 53, the boom operation valve 54, and the arm operation valve 52 (see FIG. 1 for the operation valves 51 to 54). .
  • a non-turning pressure detector 82 is provided for detecting that the pilot pressure has been established.
  • the non-turning pressure detector 82 is configured to selectively detect the pilot pressure of the highest pilot pressure among all the pilot lines (62A to 64B) of the pilot circuits 62 to 64.
  • a pressure sensor is used as the non-turning pressure detector 82.
  • the non-turning pressure detector 82 may be a pressure switch that is turned on or off when a pilot pressure is established in any of the pilot circuits 62 to 64.
  • the controller 8 increases the power shift pressure Ps and the discharge flow rates of the first hydraulic pump 21 and the second hydraulic pump 22.
  • the proportional valve 72 is controlled so as to decrease.
  • the spool operation detection line 73 is cut off when the turning spool 41 is operated, it is possible to detect a turning single operation using a turning spool having a normal structure. it can.
  • the hydraulic drive system incorporated in the existing construction machine can be modified at low cost to the hydraulic drive system of the present embodiment.
  • the bucket spool 44 is configured not to block the spool operation detection line 73 even when it operates in the bucket-out direction.
  • the bucket pilot circuit 63 is provided with a bucket-out pressure detector 83 for detecting that the pilot pressure in the bucket-out line 63B has risen.
  • a pressure sensor is used as the bucket-out pressure detector 83.
  • the bucket-out pressure detector 83 may be a pressure switch that is turned on or off when the pilot pressure of the bucket-out line 63B is raised.
  • the boom pilot circuit 64 is provided with a boom lowering pressure detector 84 for detecting that the pilot pressure of the boom lowering line 64B has been raised.
  • a pressure sensor is used as the boom lowering pressure detector 84.
  • the boom lowering pressure detector 84 may be a pressure switch that is turned on or off when the pilot pressure of the boom lowering line 64B is raised.
  • the controller 8 controls the proportional valve 72 so that the power shift pressure Ps becomes high in the following four cases. Thereby, the discharge flow rate with respect to the discharge pressure of each of the first hydraulic pump 21 and the second hydraulic pump 22 decreases. As a result, the amount of hydraulic oil supplied to the turning hydraulic motor 24 during turning acceleration can be suppressed, and wasteful consumption of energy can be suppressed. Note that the controller 8 may control the proportional valve 72 so that the power shift pressure Ps is restored after the acceleration period of turning has passed.
  • the first of the four cases described above is based on the pilot pressure detection by the turning pressure detector 81 and the non-detection of the monitoring pressure detector 75, the bucket-out pressure detector 83, and the boom lowering pressure detector 84. This is a case where it is determined that only the operation valve 51 has been operated.
  • the swing operation valve 51 is operated by the pilot pressure detection by the swing pressure detector 81 and the bucket-out pressure detector 83 and the non-detection of the monitoring pressure detector 75 and the boom lowering pressure detector 84. And it is a case where it determines with the bucket operation valve 53 having been operated in the bucket out direction.
  • the turning operation valve 51 is operated by detecting the pilot pressure by the turning pressure detector 81 and the boom lowering pressure detector 84 and by not detecting the monitoring pressure detector 75 and the bucket-out pressure detector 83. And it is a case where it determines with the boom operation valve 54 having been operated by the boom lowering direction.
  • the swing operation valve 51 is operated by the pilot pressure detection by the swing pressure detector 81, the bucket-out pressure detector 83, and the boom lowering pressure detector 84 and the non-detection of the monitoring pressure detector 75. In this case, it is determined that the bucket operation valve 53 is operated in the bucket-out direction and the boom operation valve 54 is operated in the boom lowering direction.
  • the non-turning pressure detector 82 shown in FIG. 7 is employed as in the second embodiment, the turning spool 41, the bucket spool 44, and the boom spool 45 are replaced with a normal one as shown in FIG. It can be changed to a structure (a structure that shuts off the spool operation detection line 73 when it is operated).
  • the non-turning pressure detector 82 since the bucket-out pressure detector 83 and the boom lowering pressure detector 84 are provided in this embodiment, as shown in FIG. 7, the non-turning pressure detector 82 selectively applies the pilot pressure.
  • the boom lowering line 64B and the bucket out line 63B may be removed from the pilot line to be detected.
  • the bucket-in pressure detector is connected to the bucket-in line 63A of the bucket pilot circuit 63.
  • a boom raising pressure detector 86 is provided on the boom raising line 64A of the boom pilot circuit 64
  • an arm pressure detector 87 is provided on the arm pilot circuit 62 (arm-in line 62A and arm-out line 62B).
  • the bucket-in pressure detector 85 is for detecting that the pilot pressure in the bucket-in line 63A has been established, and the boom raising pressure detector 86 has been established in the boom raising line 64A.
  • the arm pressure detector 87 is for detecting that the pilot pressure of the arm pilot circuit 62 (arm-in line 62A and arm-out line 62B) has been established.
  • the present embodiment can provide the same effects as those of the third embodiment.
  • the pressure detectors are provided in the pilot circuits 61 to 64 of all the operation valves 51 to 54, the monitoring spool 40 is a swirl spool 41 having a normal structure, and a bucket spool 44. Even if the boom spool 45 and the arm spool 46 are used, it is possible to detect the turning operation alone. As a result, the hydraulic drive system incorporated in the existing construction machine can be retrofitted to the hydraulic drive system of the present embodiment at a low cost.
  • the arm spool 46 of the second multi-control valve 4B is the monitoring spool 40.
  • the arm spool 43 of the first multi-control valve 4A is monitored.
  • the spool 40 may be used.
  • the bucket pilot circuit 63 uses a bucket-in line instead of the bucket-out pressure detector 83 and the bucket-in pressure detector 85.
  • a pressure detector (not shown) configured to selectively detect a pilot pressure having a higher pilot pressure among 63A and the bucket-out line 63B may be provided.
  • the boom pilot circuit 64 uses a boom raising pressure detector 84 and a boom raising pressure detector 86 instead of the boom raising pressure detector 84.
  • a pressure detector (not shown) configured to selectively detect the pilot pressure with the higher pilot pressure out of the line 64A and the boom lowering line 64B may be provided.
  • the discharge flow rate control method of the first and second hydraulic pumps 21 and 22 is not necessarily the negative control method, and may be the positive control method. That is, the first and second regulators 3 ⁇ / b> A and 3 ⁇ / b> B may have a positive control piston instead of the negative control piston 33. Or the system (what is called an electric positive control) which performs flow control electrically may be used. Further, the control method of the discharge flow rate of the first and second hydraulic pumps 21 and 22 may be a load sensing method.
  • the hydraulic drive system of the present invention is useful for various construction machines.

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • Operation Control Of Excavators (AREA)
  • Fluid-Pressure Circuits (AREA)

Abstract

A hydraulic drive system (1A) having first and second multi-control valves (4A, 4B) connected to first and second hydraulic pumps (21, 22). First and second regulators (3A, 3B) adjust the tilt angle of the first and second hydraulic pumps (21, 22) such that the discharge flow rate thereof decreases the higher the discharge pressure thereof and the higher the power shift pressure. A proportional valve (72) that sets the power shift pressure is controlled such that the power shift pressure increases and the discharge flow rate of the first and second hydraulic pumps (21, 22) decreases, when only a rotation spool (41) operates or when the rotation spool (41) operates and at least one spool included in the second multi-control valve (4B) operates in the direction of lower required flow rate.

Description

油圧駆動システムHydraulic drive system
 本発明は、旋回油圧モータを具備する建設機械用の油圧駆動システムに関する。 The present invention relates to a hydraulic drive system for a construction machine having a swing hydraulic motor.
 油圧ショベルなどの建設機械では、一般に、エンジンにより駆動される油圧ポンプから種々の油圧アクチュエータに作動油が供給される。油圧ポンプとしては、斜板ポンプや斜軸ポンプのような可変容量型のポンプが用いられ、油圧ポンプの傾転角が変更されることによって油圧ポンプから吐出される作動油の流量が変更される。 In a construction machine such as a hydraulic excavator, hydraulic fluid is generally supplied from a hydraulic pump driven by an engine to various hydraulic actuators. As the hydraulic pump, a variable displacement pump such as a swash plate pump or a swash shaft pump is used, and the flow rate of hydraulic oil discharged from the hydraulic pump is changed by changing the tilt angle of the hydraulic pump. .
 油圧ポンプの傾転角は、一般に、レギュレータにより調整される。例えば、特許文献1には、1つのエンジンにより駆動される2つの油圧ポンプと、それらの油圧ポンプの傾転角を調整する2つのレギュレータを備えた油圧駆動システムが開示されている。この油圧駆動システムでは、過負荷によるエンジンの停止を防止するために、個々の油圧ポンプの馬力の合計がエンジンの出力を超えないように馬力制御が行われる。 ¡The tilt angle of the hydraulic pump is generally adjusted by a regulator. For example, Patent Document 1 discloses a hydraulic drive system that includes two hydraulic pumps driven by one engine and two regulators that adjust the tilt angles of the hydraulic pumps. In this hydraulic drive system, in order to prevent the engine from being stopped due to overload, horsepower control is performed so that the total horsepower of the individual hydraulic pumps does not exceed the output of the engine.
 具体的に、特許文献1では、各レギュレータに、当該レギュレータと連結された自己側油圧ポンプの吐出圧と、他方のレギュレータと連結された相手側油圧ポンプの吐出圧が導かれる。レギュレータは、自己側油圧ポンプおよび相手側油圧ポンプの吐出圧が高いほど自己側油圧ポンプの傾転角を大きくし、自己側油圧ポンプの吐出流量を増大させる。すなわち、2つの油圧ポンプの傾転角が常に同じ角度に保たれる。また、双方のレギュレータには、比例弁から制御圧が導かれ、制御圧が高いほど双方の油圧ポンプの傾転角が大きくされる。なお、当該技術分野では、自己側油圧ポンプおよび相手側油圧ポンプの吐出圧に基づく馬力制御を全馬力制御、制御圧に基づく馬力制御をパワーシフト制御と呼ぶこともある。 Specifically, in Patent Document 1, the discharge pressure of the self-side hydraulic pump connected to the regulator and the discharge pressure of the counterpart hydraulic pump connected to the other regulator are led to each regulator. The regulator increases the tilt angle of the self-side hydraulic pump and increases the discharge flow rate of the self-side hydraulic pump as the discharge pressure of the self-side hydraulic pump and the counterpart hydraulic pump increases. That is, the tilt angles of the two hydraulic pumps are always kept at the same angle. In addition, the control pressure is guided to the both regulators from the proportional valve, and the tilt angle of both hydraulic pumps is increased as the control pressure is higher. In this technical field, horsepower control based on the discharge pressures of the self-side hydraulic pump and the counterpart hydraulic pump is sometimes referred to as total horsepower control, and horsepower control based on the control pressure is sometimes referred to as power shift control.
 より詳しくは、各レギュレータは、自己側油圧ポンプに連結されたサーボシリンダと、サーボシリンダを制御するためのスプールと、自己側油圧ポンプおよび相手側油圧ポンプの吐出圧ならびに制御圧が高いほど自己側油圧ポンプの吐出流量を増大させる方向にスプールを押圧する馬力制御用ピストンを含む。 More specifically, each regulator includes a servo cylinder connected to the self-side hydraulic pump, a spool for controlling the servo cylinder, and the self-side hydraulic pump and the counterpart hydraulic pump having higher discharge pressure and control pressure. It includes a horsepower control piston that presses the spool in a direction that increases the discharge flow rate of the hydraulic pump.
 なお、特許文献1に開示された油圧駆動システムでは、油圧ショベルが対象となっており、一方の油圧ポンプからはコントロールバルブを介して旋回油圧モータなどに作動油が供給され、他方の油圧ポンプからはコントロールバルブを介してバケットシリンダなどに作動油が供給される。 The hydraulic drive system disclosed in Patent Document 1 is intended for a hydraulic excavator, and hydraulic oil is supplied from one hydraulic pump to a swing hydraulic motor or the like via a control valve, and from the other hydraulic pump. The hydraulic oil is supplied to the bucket cylinder and the like through the control valve.
特開平11-101183号公報JP-A-11-101183
 ところで、特許文献1に開示された油圧駆動システムにおいては、レギュレータの馬力制御用ピストンがスプールを押圧する方向を逆にすることが考えられる。換言すれば、各レギュレータを、自己側油圧ポンプおよび相手側油圧ポンプの吐出圧ならびに制御圧が高くなるほど自己側油圧ポンプの吐出流量を減少させるように構成する。このようにすれば、一方の油圧ポンプが無負荷のときに、他方の油圧ポンプの吐出流量を大きくできるというメリットがある。例えば、図9Aに、一方の油圧ポンプの性能特性を、当該油圧ポンプおよび他方の油圧ポンプに同じ負荷がかかったときを実線Aで示し、他方の油圧ポンプが無負荷の場合を一点鎖線Bで示す。上記のメリットは、例えば、バケット単独操作の場合に効果的である。 Incidentally, in the hydraulic drive system disclosed in Patent Document 1, it is conceivable to reverse the direction in which the horsepower control piston of the regulator presses the spool. In other words, each regulator is configured to decrease the discharge flow rate of the self-side hydraulic pump as the discharge pressure and control pressure of the self-side hydraulic pump and the counterpart hydraulic pump increase. In this way, when one hydraulic pump is unloaded, there is an advantage that the discharge flow rate of the other hydraulic pump can be increased. For example, in FIG. 9A, the performance characteristics of one hydraulic pump are shown by a solid line A when the same load is applied to the hydraulic pump and the other hydraulic pump, and the one-dot chain line B shows the case where the other hydraulic pump is unloaded. Show. The above merits are effective, for example, in the case of single bucket operation.
 しかしながら、旋回単独操作の場合は、旋回油圧モータにより旋回される旋回体が旋回し始める初期に、上記のメリットによって増大された吐出流量が過大となる。これは、建設機械では旋回体の重量(厳密に言えば、イナーシャ)が大きいために、旋回加速時の初期には多くの流量は不要であるからである。旋回加速時に旋回油圧モータに供給される余分な作動油は、旋回油圧モータのリリーフ弁から逃される。このように、旋回単独操作の場合には、旋回加速時にエネルギーが無駄に消費されることになる。 However, in the case of a single turning operation, the discharge flow rate increased by the above-mentioned merit becomes excessive at the initial stage of the turning body turned by the turning hydraulic motor. This is because, in construction machines, the weight of the revolving structure (strictly speaking, inertia) is large, so that a large flow rate is not necessary at the initial stage of the acceleration of turning. Excess hydraulic oil supplied to the swing hydraulic motor at the time of swing acceleration is released from the relief valve of the swing hydraulic motor. Thus, in the case of a single turn operation, energy is wasted when turning acceleration.
 そこで、本発明は、旋回単独操作またはそれに準じた操作のときに旋回加速時のエネルギーの無駄な消費を抑制することができる油圧駆動システムを提供することを目的とする。 Therefore, an object of the present invention is to provide a hydraulic drive system that can suppress wasteful consumption of energy during turning acceleration during a turning single operation or a similar operation.
 前記課題を解決するために、本発明の油圧駆動システムは、旋回油圧モータを具備する建設機械用の油圧駆動システムであって、エンジンにより駆動されて傾転角に応じた流量の作動油を吐出する第1油圧ポンプおよび第2油圧ポンプと、前記第1油圧ポンプと接続された、前記旋回油圧モータを制御するための旋回用スプールを含む第1マルチコントロールバルブと、前記第2油圧ポンプと接続された第2マルチコントロールバルブと、前記第1油圧ポンプおよび前記第2油圧ポンプの吐出圧ならびにパワーシフト圧に応じて、それらが高くなるほど前記第1ポンプの吐出流量が減少するように前記第1油圧ポンプの傾転角を調整する第1レギュレータと、前記第2油圧ポンプおよび前記第1油圧ポンプの吐出圧ならびに前記パワーシフト圧に応じて、それらが高くなるほど前記第2ポンプの吐出流量が減少するように前記第2油圧ポンプの傾転角を調整する第2レギュレータと、前記第1レギュレータおよび前記第2レギュレータに導かれる前記パワーシフト圧を設定する比例弁と、前記旋回用スプールのみが作動したとき、または前記旋回用スプールが作動し、かつ、前記第2マルチコントロールバルブに含まれる1つまたは複数のスプールが必要流量が少ない方向に作動したときに、前記パワーシフト圧が高くなって前記第1油圧ポンプおよび前記第2油圧ポンプの吐出流量が減少するように前記比例弁を制御するコントローラと、を備える、ことを特徴とする。 In order to solve the above-mentioned problems, a hydraulic drive system according to the present invention is a hydraulic drive system for a construction machine having a swing hydraulic motor, and is driven by an engine to discharge hydraulic oil at a flow rate corresponding to a tilt angle. The first hydraulic pump and the second hydraulic pump, the first multi-control valve connected to the first hydraulic pump and including a swing spool for controlling the swing hydraulic motor, and the second hydraulic pump The first multi-control valve, the first hydraulic pump and the discharge pressure and power shift pressure of the second hydraulic pump, and the first pump so that the discharge flow rate of the first pump decreases as they increase. A first regulator for adjusting a tilt angle of the hydraulic pump; a discharge pressure of the second hydraulic pump; the first hydraulic pump; and the power shift According to the pressure, the higher the pressure is, the more the discharge flow rate of the second pump is decreased. The second regulator adjusts the tilt angle of the second hydraulic pump, and the first regulator and the second regulator guide the pressure. When only the proportional valve for setting the power shift pressure and the turning spool are operated, or when the turning spool is operated, and one or more spools included in the second multi-control valve are required flow rate A controller that controls the proportional valve so that the power shift pressure is increased and the discharge flow rates of the first hydraulic pump and the second hydraulic pump are decreased when operated in a direction with less pressure. Features.
 上記の構成によれば、旋回単独操作またはそれに準じた操作のときには、第1油圧ポンプの吐出流量が減少するので、旋回加速時のエネルギーの無駄な消費を抑制することができる。 According to the above configuration, the discharge flow rate of the first hydraulic pump is reduced during a single turn operation or a similar operation, so that wasteful consumption of energy during turn acceleration can be suppressed.
 上記の油圧駆動システムは、前記旋回用スプールを含む監視用スプールを経由するように前記第1マルチコントロールバルブおよび前記第2マルチコントロールバルブに跨って延びるスプール作動検出ラインと、前記スプール作動検出ラインが遮断されたことを検出するための監視用圧力検出器と、前記旋回用スプールを作動させるパイロット回路のパイロット圧が立ったことを検出するための旋回用圧力検出器と、をさらに備え、前記旋回用スプールは、作動したときでも前記スプール作動検出ラインを遮断しないように構成されていてもよい。この構成によれば、簡単な構成で旋回単独操作を検出することができる。 The hydraulic drive system includes a spool operation detection line extending across the first multi-control valve and the second multi-control valve so as to pass through the monitoring spool including the turning spool, and the spool operation detection line. A pressure detector for monitoring for detecting the shut-off, and a pressure detector for turning for detecting that a pilot pressure of a pilot circuit for operating the turning spool has been established. The spool may be configured not to block the spool operation detection line even when it is operated. According to this configuration, the turning single operation can be detected with a simple configuration.
 あるいは、上記の油圧駆動システムは、前記旋回用スプールを含む監視用スプールを経由するように前記第1マルチコントロールバルブおよび前記第2マルチコントロールバルブに跨って延びるスプール作動検出ラインと、前記旋回用スプールを作動させるパイロット回路のパイロット圧が立ったことを検出するための旋回用圧力検出器と、前記旋回用スプール以外の前記監視用スプールを作動させるパイロット回路のいずれかにおいてパイロット圧が立ったことを検出するための非旋回用圧力検出器と、をさらに備え、前記旋回用スプールは、作動したときに前記スプール作動検出ラインを遮断するように構成されていてもよい。この構成によれば、通常の構造の旋回用スプールを用いて旋回単独操作を検出することができる。 Alternatively, the hydraulic drive system includes a spool operation detection line extending over the first multi-control valve and the second multi-control valve so as to pass through a monitoring spool including the turning spool, and the turning spool. The pilot pressure is detected in any one of the turning pressure detector for detecting that the pilot pressure of the pilot circuit for operating the pressure is raised and the pilot circuit for operating the monitoring spool other than the turning spool. And a non-turning pressure detector for detecting, wherein the turning spool may be configured to shut off the spool operation detection line when operated. According to this configuration, it is possible to detect a single turning operation using a turning spool having a normal structure.
 前記建設機械は、バケット、アームおよびブームを備える油圧ショベルであり、前記第2マルチコントロールバルブは、前記監視用スプールとして、バケット用スプールとブーム用スプールを含み、前記バケット用スプールは、バケットアウトの方向に作動したときでも前記スプール作動検出ラインを遮断しないように構成されており、前記ブーム用スプールは、ブーム下げの方向に作動したときでも前記スプール作動検出ラインを遮断しないように構成されており、上記の油圧駆動システムは、前記バケット用スプールを作動させるパイロット回路におけるバケットアウト用ラインのパイロット圧が立ったことを検出するためのバケットアウト用圧力検出器と、前記ブーム用スプールを作動させるパイロット回路におけるブーム下げ用ラインのパイロット圧が立ったことを検出するためのブーム下げ用圧力検出器と、をさらに備えてもよい。この構成によれば、旋回操作だけでなく、必要流量が少ないバケットアウト操作およびブーム下げ操作も検出することができる。これにより、旋回とブーム下げの同時操作、旋回とバケットアウトの同時操作、旋回とブーム下げとバケットアウトの同時操作という頻繁に行われる操作のときに、旋回加速時のエネルギーの無駄な消費を抑制することができる。 The construction machine is a hydraulic excavator including a bucket, an arm, and a boom. The second multi-control valve includes a bucket spool and a boom spool as the monitoring spool, and the bucket spool is a bucket-out spool. The spool operation detection line is configured not to be interrupted even when operated in the direction, and the boom spool is configured not to interrupt the spool operation detection line even when operated in the boom lowering direction. The hydraulic drive system includes a bucket-out pressure detector for detecting that a pilot pressure in a bucket-out line in the pilot circuit that operates the bucket spool is raised, and a pilot that operates the boom spool. Boom lowering circuit A boom-lowering pressure detector for detecting the pilot pressure of the emissions stood, it may further comprise a. According to this configuration, it is possible to detect not only a turning operation but also a bucket-out operation and a boom lowering operation with a small required flow rate. This reduces wasteful energy consumption during turning acceleration during simultaneous operations of turning and boom lowering, turning and bucket out, and turning and boom lowering and bucket out. can do.
 前記建設機械は、バケット、アームおよびブームを備える油圧ショベルであり、上記の油圧駆動システムは、前記旋回用スプールを含む監視用スプールを経由するように前記第1マルチコントロールバルブおよび前記第2マルチコントロールバルブに跨って延びるスプール作動検出ラインをさらに備えてもよい。さらに、前記第1マルチコントロールバルブと前記第2マルチコントロールバルブのどちらかは、前記監視用スプールとして、アーム用スプールを含み、前記第2マルチコントロールバルブは、前記監視用スプールとして、バケット用スプールとブーム用スプールを含み、前記旋回用スプール、前記アーム用スプール、前記バケット用スプールおよび前記ブーム用スプールは、作動したときに前記スプール作動検出ラインを遮断するように構成されており、前記旋回用スプール、前記アーム用スプール、前記バケット用スプールおよび前記ブーム用スプールを作動させるパイロット回路のそれぞれには、当該パイロット回路のパイロット圧が立ったことを検出するための圧力検出器が設けられていてもよい。この構成によれば、既存の建設機械に組み込まれた油圧駆動システムを、本発明の油圧駆動システムに安価に改造することができる。 The construction machine is a hydraulic excavator including a bucket, an arm, and a boom, and the hydraulic drive system includes the first multi-control valve and the second multi-control so as to pass through a monitoring spool including the turning spool. A spool operation detection line extending across the valve may be further provided. Further, either the first multi-control valve or the second multi-control valve includes an arm spool as the monitoring spool, and the second multi-control valve includes a bucket spool as the monitoring spool. A boom spool, wherein the swing spool, the arm spool, the bucket spool, and the boom spool are configured to shut off the spool operation detection line when operated, and the swing spool Each of the pilot circuits for operating the arm spool, the bucket spool, and the boom spool may be provided with a pressure detector for detecting that the pilot pressure of the pilot circuit is established. . According to this configuration, a hydraulic drive system incorporated in an existing construction machine can be modified at low cost into the hydraulic drive system of the present invention.
 本発明によれば、旋回単独操作またはそれに準じた操作のときに旋回加速時のエネルギーの無駄な消費を抑制することができる。 According to the present invention, it is possible to suppress wasteful consumption of energy at the time of turning acceleration during a turning single operation or a similar operation.
本発明の第1実施形態に係る油圧駆動システムの全体的な油圧回路図である。1 is an overall hydraulic circuit diagram of a hydraulic drive system according to a first embodiment of the present invention. 第1実施形態における第1および第2マルチコントロールバルブから油圧アクチュエータまでの油圧回路図である。It is a hydraulic circuit diagram from the 1st and 2nd multi-control valve in a 1st embodiment to a hydraulic actuator. 本発明の第2実施形態における旋回以外の操作を検出するための油圧回路図である。It is a hydraulic-circuit figure for detecting operation other than turning in 2nd Embodiment of this invention. 第2実施形態における第1および第2マルチコントロールバルブから油圧アクチュエータまでの油圧回路図である。It is a hydraulic circuit diagram from the 1st and 2nd multi control valve in a 2nd embodiment to a hydraulic actuator. 本発明の第3実施形態に係る油圧駆動システムの全体的な油圧回路図である。FIG. 5 is an overall hydraulic circuit diagram of a hydraulic drive system according to a third embodiment of the present invention. 第3実施形態における第1および第2マルチコントロールバルブから油圧アクチュエータまでの油圧回路図である。It is a hydraulic circuit diagram from the 1st and 2nd multi-control valve in a 3rd embodiment to a hydraulic actuator. 第3実施形態の変形例における旋回以外の操作を検出するための油圧回路図である。It is a hydraulic circuit figure for detecting operation other than turning in the modification of a 3rd embodiment. 本発明の第4実施形態に係る油圧駆動システムの全体的な油圧回路図である。It is a whole hydraulic circuit diagram of the hydraulic drive system concerning a 4th embodiment of the present invention. 図9Aは従来の油圧駆動システムにおける一方の油圧ポンプの性能特性を示すグラフであり、図9Bは第1実施形態における第1油圧ポンプの性能特性を示すグラフである。FIG. 9A is a graph showing the performance characteristics of one hydraulic pump in the conventional hydraulic drive system, and FIG. 9B is a graph showing the performance characteristics of the first hydraulic pump in the first embodiment.
 (第1実施形態)
 図1および図2に、本発明の第1実施形態に係る油圧駆動システム1Aを示す。図1は、後述する第1および第2マルチコントロールバルブ4A,4Bの内部構成を簡略的に示す油圧駆動システム1Aの全体的な油圧回路図であり、図2は、第1および第2マルチコントロールバルブ4A,4Bから油圧アクチュエータまでの油圧回路図である。
(First embodiment)
1 and 2 show a hydraulic drive system 1A according to a first embodiment of the present invention. FIG. 1 is an overall hydraulic circuit diagram of a hydraulic drive system 1A schematically showing the internal configuration of first and second multi-control valves 4A and 4B described later, and FIG. 2 shows first and second multi-control valves. FIG. 3 is a hydraulic circuit diagram from valves 4A and 4B to a hydraulic actuator.
 油圧駆動システム1Aは、旋回油圧モータを具備する建設機械用のものである。本実施形態では、建設機械が油圧ショベルである。ただし、油圧駆動システム1Aが対象とする建設機械は、必ずしも油圧ショベルである必要はなく、例えば油圧クレーンなどであってもよい。 The hydraulic drive system 1A is for a construction machine equipped with a swing hydraulic motor. In this embodiment, the construction machine is a hydraulic excavator. However, the construction machine targeted by the hydraulic drive system 1A is not necessarily a hydraulic excavator, and may be a hydraulic crane, for example.
 例えば、自走式の油圧ショベルは、走行装置、走行装置に対して旋回する、運転室を含む本体、本体に対して俯仰するブーム、ブームの先端に揺動可能に連結されたアーム、アームの先端に揺動可能に連結されたバケット、を備える。すなわち、本体、ブーム、アームおよびバケットが、後述する旋回油圧モータ24により旋回される旋回体である。船舶に搭載される油圧ショベルでは、本体が船体に旋回可能に支持される。 For example, a self-propelled hydraulic excavator includes a traveling device, a main body including a driver's cab that swivels with respect to the traveling device, a boom that is lifted with respect to the main body, an arm that is swingably connected to a tip of the boom, A bucket that is swingably coupled to the tip. That is, the main body, the boom, the arm, and the bucket are revolving bodies that are revolved by a revolving hydraulic motor 24 described later. In a hydraulic excavator mounted on a ship, the main body is supported by the hull so as to be able to turn.
 図2に示すように、油圧駆動システム1Aは、油圧アクチュエータとして、旋回油圧モータ24、バケットシリンダ25、ブームシリンダ26、アームシリンダ27を備える。また、油圧駆動システム1Aは、図1に示すように、それらの油圧アクチュエータに作動油を供給する第1油圧ポンプ21および第2油圧ポンプ22を備える。第1油圧ポンプ21からは、第1マルチコントロールバルブ4Aを介して旋回油圧モータ24、ブームシリンダ26およびアームシリンダ27に作動油が供給され、第2油圧ポンプ22からは、第2マルチコントロールバルブ4Bを介してバケットシリンダ25、ブームシリンダ26およびアームシリンダ27に作動油が供給される。 2, the hydraulic drive system 1A includes a swing hydraulic motor 24, a bucket cylinder 25, a boom cylinder 26, and an arm cylinder 27 as hydraulic actuators. Moreover, the hydraulic drive system 1A includes a first hydraulic pump 21 and a second hydraulic pump 22 that supply hydraulic oil to those hydraulic actuators, as shown in FIG. Hydraulic fluid is supplied from the first hydraulic pump 21 to the swing hydraulic motor 24, the boom cylinder 26, and the arm cylinder 27 via the first multi-control valve 4A, and from the second hydraulic pump 22, the second multi-control valve 4B. Hydraulic oil is supplied to the bucket cylinder 25, the boom cylinder 26, and the arm cylinder 27 via.
 より詳しくは、第1油圧ポンプ21は、第1供給ライン11により第1マルチコントロールバルブ4Aと接続されている。また、第1マルチコントロールバルブ4Aからは、当該第1マルチコントロールバルブ4Aを通過した作動油をタンクに導く第1センターブリードライン12が延びている。同様に、第2油圧ポンプ22は、第2供給ライン15により第2マルチコントロールバルブ4Bと接続されている。また、第2マルチコントロールバルブ4Bからは、当該第2マルチコントロールバルブ4Bを通過した作動油をタンクに導く第2センターブリードライン16が延びている。 More specifically, the first hydraulic pump 21 is connected to the first multi-control valve 4A by the first supply line 11. A first center bleed line 12 that guides hydraulic oil that has passed through the first multi-control valve 4A to the tank extends from the first multi-control valve 4A. Similarly, the second hydraulic pump 22 is connected to the second multi-control valve 4B by the second supply line 15. A second center bleed line 16 that guides hydraulic oil that has passed through the second multi-control valve 4B to the tank extends from the second multi-control valve 4B.
 本実施形態では、第1油圧ポンプ21の吐出流量および第2油圧ポンプ22の吐出流量がネガティブコントロール(以下、「ネガコン」という)方式で制御される。すなわち、第1センターブリードライン12に絞り13が設けられているとともに、この絞り13をバイパスする通路上にリリーフ弁14が配置されている。同様に、第2センターブリードライン16に絞り17が設けられているとともに、この絞り17をバイパスする通路上にリリーフ弁18が配置されている。なお、リリーフ弁14,18及び絞り13,17は、それぞれ第1マルチコントロールバルブ4Aおよび第2マルチコントロールバルブ4Bに組み込まれていてもよい。 In this embodiment, the discharge flow rate of the first hydraulic pump 21 and the discharge flow rate of the second hydraulic pump 22 are controlled by a negative control (hereinafter referred to as “negative control”) method. That is, a throttle 13 is provided in the first center bleed line 12, and a relief valve 14 is disposed on a passage that bypasses the throttle 13. Similarly, a throttle 17 is provided in the second center bleed line 16, and a relief valve 18 is disposed on a passage that bypasses the throttle 17. The relief valves 14 and 18 and the throttles 13 and 17 may be incorporated in the first multi-control valve 4A and the second multi-control valve 4B, respectively.
 第1マルチコントロールバルブ4Aおよび第2マルチコントロールバルブ4Bは、複数のスプールを含むオープンセンター型のバルブである。すなわち、マルチコントロールバルブ(4Aまたは4B)では、全てのスプールが中立位置にあるときに供給ライン(11または15)からセンターブリードライン(12または16)へ流れる作動油の量が制限されない一方、いずれかのスプールが作動して中立位置から移動すると、供給ライン(11または15)からセンターブリードライン(12または16)へ流れる作動油の量がそのスプールによって制限される。 The first multi-control valve 4A and the second multi-control valve 4B are open center type valves including a plurality of spools. That is, in the multi-control valve (4A or 4B), the amount of hydraulic fluid flowing from the supply line (11 or 15) to the center bleed line (12 or 16) is not limited when all the spools are in the neutral position. When that spool is activated and moved from the neutral position, the amount of hydraulic fluid flowing from the supply line (11 or 15) to the center bleed line (12 or 16) is limited by the spool.
 より詳しくは、図2に示すように、第1マルチコントロールバルブ4Aは、旋回油圧モータ24を制御するための旋回用スプール41を含み、第2マルチコントロールバルブ4Bは、バケットシリンダ25を制御するためのバケット用スプール44を含む。また、第1マルチコントロールバルブ4Aおよび第2マルチコントロールバルブ4Bは、ブームシリンダ26を制御するためのブーム用スプール42,45と、アームシリンダ27を制御するためのアーム用スプール43,46をそれぞれ含む。第2マルチコントロールバルブ4Bのブーム用スプール45は第1速度を、第1マルチコントロールバルブ4Aのブーム用スプール42は、ブーム用スプール45と共に作動して、第1速度よりも速い第2速度を実現するためのものである。なお、ブーム用スプール45とブームシリンダ26の間のヘッド側ラインに合流する、ブーム用スプール42からのライン上には逆止弁47が配置されている。第1マルチコントロールバルブ4Aのアーム用スプール44は第1速度を、第2マルチコントロールバルブ4Bのアーム用スプール46は、アーム用スプール44と共に作動して、第1速度よりも速い第2速度を実現するためのものである。なお、ブーム第2速度用のブーム用スプール42のみが2ポジションスプールであり、その他のスプールは3ポジションスプールである。 More specifically, as shown in FIG. 2, the first multi-control valve 4A includes a swing spool 41 for controlling the swing hydraulic motor 24, and the second multi-control valve 4B controls the bucket cylinder 25. The bucket spool 44 is included. The first multi-control valve 4A and the second multi-control valve 4B include boom spools 42 and 45 for controlling the boom cylinder 26 and arm spools 43 and 46 for controlling the arm cylinder 27, respectively. . The boom spool 45 of the second multi-control valve 4B operates at the first speed, and the boom spool 42 of the first multi-control valve 4A operates together with the boom spool 45 to achieve a second speed higher than the first speed. Is to do. A check valve 47 is disposed on the line from the boom spool 42, which joins the head side line between the boom spool 45 and the boom cylinder 26. The arm spool 44 of the first multi-control valve 4A operates at the first speed, and the arm spool 46 of the second multi-control valve 4B operates together with the arm spool 44 to achieve a second speed higher than the first speed. Is to do. Only the boom spool 42 for the second boom speed is a 2-position spool, and the other spools are 3-position spools.
 また、第1マルチコントロールバルブ4Aおよび第2マルチコントロールバルブ4Bのそれぞれには、全てのスプールを横断して供給ライン(11または15)とセンターブリードライン(12または16)とを接続する中央通路4aと、中央通路4aから各スプールへ作動油を導くパラレル通路4bと、各スプール(ブーム用スプール42を除く)からタンクへ作動油を導くタンク通路4cが形成されている。 Further, each of the first multi-control valve 4A and the second multi-control valve 4B has a central passage 4a that connects the supply line (11 or 15) and the center bleed line (12 or 16) across all spools. A parallel passage 4b that guides hydraulic oil from the central passage 4a to each spool and a tank passage 4c that guides hydraulic oil from each spool (excluding the boom spool 42) to the tank are formed.
 なお、スプール41~46の位置は特に限定されるものではなく、図2に示されている通りである必要はない。例えば、バケット用スプール44がブーム用スプール45の下流側であってアーム用スプール46の上流側に配置されていてもよい。また、自走式の油圧ショベルの場合には、第1マルチコントロールバルブ4Aおよび第2マルチコントロールバルブ4Bのそれぞれに、走行油圧モータを制御するための走行用スプールが含まれていてもよい。さらに、第1マルチコントロールバルブ4A若しくは第2マルチコントロールバルブ4Bのいずれか一方、又はその両方に、オプション用スプールが1個又は複数個含まれていてもよい。 It should be noted that the positions of the spools 41 to 46 are not particularly limited and need not be as shown in FIG. For example, the bucket spool 44 may be disposed downstream of the boom spool 45 and upstream of the arm spool 46. In the case of a self-propelled hydraulic excavator, each of the first multi-control valve 4A and the second multi-control valve 4B may include a traveling spool for controlling the traveling hydraulic motor. Furthermore, one or a plurality of option spools may be included in either one or both of the first multi-control valve 4A and the second multi-control valve 4B.
 旋回用スプール41を作動させる旋回パイロット回路61は、旋回操作弁51から旋回用スプール41まで延びる右旋回ライン61Aおよび左旋回ライン61Bを含み、バケット用スプール44を作動させるバケットパイロット回路63は、バケット操作弁53からバケット用スプール44まで延びるバケットイン用ライン63Aおよびバケットアウト用ライン63Bを含む。また、ブーム用スプール42,45を作動させるブームパイロット回路64は、ブーム操作弁54からブーム用スプール42,45まで延びるブーム上げ用ライン64Aおよびブーム操作弁54からブーム用スプール45のみまで延びるブーム下げ用ライン64Bを含み、アーム用スプール43,46を作動させるアームパイロット回路62は、アーム操作弁52からアーム用スプール43,46まで延びるアームイン用ライン62Aおよびアームアウト用ライン62Bを含む。各操作弁51~54は、操作レバーを含む。操作レバーが傾倒されると、パイロット回路(61~64)における操作レバーが傾倒された方向のパイロットライン(61A~64B)にパイロット圧が立ち、スプール(41~46)が作動する。 The turning pilot circuit 61 for operating the turning spool 41 includes a right turning line 61A and a left turning line 61B extending from the turning operation valve 51 to the turning spool 41, and the bucket pilot circuit 63 for operating the bucket spool 44 includes: A bucket-in line 63A and a bucket-out line 63B extending from the bucket operation valve 53 to the bucket spool 44 are included. The boom pilot circuit 64 that operates the boom spools 42 and 45 includes a boom raising line 64A extending from the boom operation valve 54 to the boom spools 42 and 45, and a boom lowering extending only from the boom operation valve 54 to the boom spool 45. The arm pilot circuit 62 including the working line 64B and operating the arm spools 43 and 46 includes an arm-in line 62A and an arm-out line 62B extending from the arm operation valve 52 to the arm spools 43 and 46. Each operation valve 51 to 54 includes an operation lever. When the operation lever is tilted, pilot pressure is generated in the pilot lines (61A to 64B) in the direction in which the operation lever in the pilot circuit (61 to 64) is tilted, and the spools (41 to 46) are operated.
 第1油圧ポンプ21および第2油圧ポンプ22は、エンジン10により駆動されて、傾転角に応じた流量の作動油を吐出する。本実施形態では、第1油圧ポンプ21および第2油圧ポンプ22として、斜板20の角度により傾転角が規定される斜板ポンプが採用されている。ただし、第1油圧ポンプ21および第2油圧ポンプ22は、斜軸の角度により傾転角が規定される斜軸ポンプであってもよい。 The first hydraulic pump 21 and the second hydraulic pump 22 are driven by the engine 10 and discharge hydraulic oil at a flow rate corresponding to the tilt angle. In the present embodiment, a swash plate pump whose tilt angle is defined by the angle of the swash plate 20 is employed as the first hydraulic pump 21 and the second hydraulic pump 22. However, the first hydraulic pump 21 and the second hydraulic pump 22 may be a slant shaft pump whose tilt angle is defined by a slant shaft angle.
 第1油圧ポンプ21の傾転角は、第1レギュレータ3Aにより調整され、第2油圧ポンプ22の傾転角は、第2レギュレータ3Bにより調整される。油圧ポンプ(21または22)の傾転角が小さくなれば油圧ポンプの吐出流量が減少し、油圧ポンプの傾転角が大きくなれば油圧ポンプの吐出流量が増大する。 The tilt angle of the first hydraulic pump 21 is adjusted by the first regulator 3A, and the tilt angle of the second hydraulic pump 22 is adjusted by the second regulator 3B. When the tilt angle of the hydraulic pump (21 or 22) decreases, the discharge flow rate of the hydraulic pump decreases, and when the tilt angle of the hydraulic pump increases, the discharge flow rate of the hydraulic pump increases.
 第1レギュレータ3Aは、第1油圧ポンプ21の斜板20と連結されたサーボシリンダ31と、サーボシリンダ31を制御するためのスプール32と、スプール32を作動させるネガコン用ピストン33および馬力制御用ピストン34と、を含む。 The first regulator 3A includes a servo cylinder 31 connected to the swash plate 20 of the first hydraulic pump 21, a spool 32 for controlling the servo cylinder 31, a negative control piston 33 and a horsepower control piston for operating the spool 32. 34.
 サーボシリンダ31の小径側受圧室は、第1供給ライン11と連通している。スプール32は、サーボシリンダ31の大径側受圧室と第1供給ライン11とを連通させるラインの開口面積を制御するとともに、大径側受圧室とタンクとを連通させるラインの開口面積を制御する。サーボシリンダ31は、大径側受圧室が第1供給ライン11とより大きな開口面積で連通すると第1油圧ポンプ21の傾転角を小さくし、大径側受圧室がタンクとより大きな開口面積で連通すると第1油圧ポンプ21の傾転を大きくする。ネガコン用ピストン33および馬力制御用ピストン34は、サーボシリンダ31の大径側受圧室を第1供給ライン11と連通させる方向、すなわち第1油圧ポンプ21の吐出流量を減少させる方向にスプール32を押圧する。 The small diameter side pressure receiving chamber of the servo cylinder 31 communicates with the first supply line 11. The spool 32 controls the opening area of the line connecting the large diameter side pressure receiving chamber of the servo cylinder 31 and the first supply line 11 and also controls the opening area of the line connecting the large diameter side pressure receiving chamber and the tank. . The servo cylinder 31 reduces the tilt angle of the first hydraulic pump 21 when the large diameter side pressure receiving chamber communicates with the first supply line 11 with a larger opening area, and the large diameter side pressure receiving chamber has a larger opening area with the tank. When communicating, the tilt of the first hydraulic pump 21 is increased. The negative control piston 33 and the horsepower control piston 34 press the spool 32 in a direction in which the large-diameter pressure receiving chamber of the servo cylinder 31 communicates with the first supply line 11, that is, in a direction in which the discharge flow rate of the first hydraulic pump 21 decreases. To do.
 第1レギュレータ3Aには、ネガコン用ピストン33にスプール32を押圧させるための受圧室が形成されている。ネガコン用ピストン33の受圧室には、第1センターブリードライン12における絞り13の上流側の圧力である第1ネガコン圧Pn1が導かれる。第1ネガコン圧Pn1は、中央通路4aに流れる作動油の、スプールによる制限度合によって定まり、第1ネガコン圧Pn1が大きくなればネガコン用ピストン33が進出して第1油圧ポンプ21の傾転角が小さくなり、第1ネガコン圧Pn1が小さくなればネガコン用ピストン33が後退して第1油圧ポンプ21の傾転角が大きくなる。 The first regulator 3A is formed with a pressure receiving chamber for causing the negative control piston 33 to press the spool 32. A first negative control pressure Pn1, which is a pressure upstream of the throttle 13 in the first center bleed line 12, is guided to the pressure receiving chamber of the negative control piston 33. The first negative control pressure Pn1 is determined by the degree of restriction of the hydraulic oil flowing through the central passage 4a by the spool. When the first negative control pressure Pn1 increases, the negative control piston 33 advances and the tilt angle of the first hydraulic pump 21 increases. If the first negative control pressure Pn1 is reduced and the negative control piston 33 is retracted, the tilt angle of the first hydraulic pump 21 is increased.
 馬力制御用ピストン34は、第1油圧ポンプ21の吐出圧Pd1および第2油圧ポンプ22の吐出圧Pd2ならびにパワーシフト圧Psに応じて、それらが高くなるほど第1油圧ポンプ21の吐出流量を減少させるためのものである。具体的に、第1レギュレータ3Aには、馬力制御用ピストン34にスプール32を押圧させるための3つの受圧室が形成されている。馬力制御用ピストン34の3つの受圧室は、それぞれ第1供給ライン11、第2供給ライン15および後述するパワーシフトライン71Aと接続されており、それらの受圧室には、それぞれ、第1油圧ポンプ21の吐出圧Pd1、第2油圧ポンプ22の吐出圧Pd2およびパワーシフト圧Psが導かれる。 The horsepower control piston 34 decreases the discharge flow rate of the first hydraulic pump 21 in accordance with the discharge pressure Pd1 of the first hydraulic pump 21, the discharge pressure Pd2 of the second hydraulic pump 22, and the power shift pressure Ps. Is for. Specifically, three pressure receiving chambers for causing the horsepower control piston 34 to press the spool 32 are formed in the first regulator 3A. The three pressure receiving chambers of the horsepower control piston 34 are connected to the first supply line 11, the second supply line 15, and a power shift line 71A described later, respectively. A discharge pressure Pd1 of 21, a discharge pressure Pd2 of the second hydraulic pump 22, and a power shift pressure Ps are introduced.
 なお、ネガコン用ピストン33と馬力制御用ピストン34は、そのうちの第1油圧ポンプ21の吐出流量を制限する方(小さくする方)が優先してスプール32を押圧するように構成される。 The negative control piston 33 and the horsepower control piston 34 are configured so as to preferentially press the spool 32 in the direction of restricting (decreasing) the discharge flow rate of the first hydraulic pump 21.
 第2レギュレータ3Bの構成は、第1レギュレータ3Aの構成と同様である。すなわち、第2レギュレータ3Bは、ネガコン用ピストン33により、第2ネガコン圧Pn2に基づいて第2油圧ポンプ22の傾転角を調整する。また、第2レギュレータ3Bは、馬力制御用ピストン34により、第2油圧ポンプ22の吐出圧Pd2および第1油圧ポンプ21の吐出圧Pd1ならびにパワーシフト圧Psに応じて、それらが高くなるほど第2油圧ポンプ22の吐出流量が減少するように第2油圧ポンプ22の傾転角を調整する。 The configuration of the second regulator 3B is the same as the configuration of the first regulator 3A. That is, the second regulator 3B adjusts the tilt angle of the second hydraulic pump 22 by the negative control piston 33 based on the second negative control pressure Pn2. Further, the second regulator 3B causes the horsepower control piston 34 to increase the second hydraulic pressure in accordance with the discharge pressure Pd2 of the second hydraulic pump 22, the discharge pressure Pd1 of the first hydraulic pump 21, and the power shift pressure Ps. The tilt angle of the second hydraulic pump 22 is adjusted so that the discharge flow rate of the pump 22 decreases.
 エンジン10により駆動される補助ポンプ23からの吐出圧は、パイロット圧供給ライン71を通じて比例弁72に一次圧として供給される。比例弁72からの制御圧はパワーシフトライン71Aへ出力され、パワーシフトライン71Aからは、一対の分岐ラインが、第1レギュレータ3Aおよび第2レギュレータ3Bにおける馬力制御用ピストン34の受圧室の1つまで延びている。 The discharge pressure from the auxiliary pump 23 driven by the engine 10 is supplied as a primary pressure to the proportional valve 72 through the pilot pressure supply line 71. The control pressure from the proportional valve 72 is output to the power shift line 71A, and a pair of branch lines from the power shift line 71A is one of the pressure receiving chambers of the horsepower control piston 34 in the first regulator 3A and the second regulator 3B. It extends to.
 比例弁72は、第1レギュレータ3Aおよび第2レギュレータ3Bに導かれるパワーシフト圧Psを設定するためのものである。 The proportional valve 72 is for setting the power shift pressure Ps guided to the first regulator 3A and the second regulator 3B.
 比例弁72は、コントローラ8により制御される。コントローラ8は、演算装置や記憶装置などで構成される。本実施形態では、コントローラ8は、旋回用スプール41のみが作動したときに、パワーシフト圧Psが高くなって第1油圧ポンプ21および第2油圧ポンプ22の吐出流量が減少するように比例弁72を制御する。以下、その制御のための構成を説明する。 The proportional valve 72 is controlled by the controller 8. The controller 8 includes an arithmetic device, a storage device, and the like. In the present embodiment, the controller 8 controls the proportional valve 72 so that the power shift pressure Ps increases and the discharge flow rates of the first hydraulic pump 21 and the second hydraulic pump 22 decrease when only the turning spool 41 operates. To control. Hereinafter, a configuration for the control will be described.
 旋回用パイロット回路61には、当該旋回パイロット回路61(右旋回ライン61Aおよび左旋回ライン61B)のパイロット圧が立ったこと、換言すれば旋回操作弁51の操作レバーが傾倒されたことを検出するための旋回用圧力検出器81が設けられている。旋回用圧力検出器81は、右旋回ライン61Aおよび左旋回ライン61Bのうちでパイロット圧が高い方のパイロット圧を選択的に検出できるように構成されている。本実施形態では、旋回用圧力検出器81として圧力センサが用いられている。ただし、旋回用圧力検出器81は、旋回パイロット回路61にパイロット圧が立ったときにオンまたはオフとなる圧力スイッチであってもよい。 The turning pilot circuit 61 detects that the pilot pressure of the turning pilot circuit 61 (the right turning line 61A and the left turning line 61B) is raised, in other words, that the operation lever of the turning operation valve 51 is tilted. A pressure detector 81 for turning is provided. The turning pressure detector 81 is configured to selectively detect the pilot pressure with the higher pilot pressure among the right turning line 61A and the left turning line 61B. In the present embodiment, a pressure sensor is used as the turning pressure detector 81. However, the turning pressure detector 81 may be a pressure switch that is turned on or off when a pilot pressure is established in the turning pilot circuit 61.
 パイロット圧供給ライン71からは、スプール作動検出ライン73が分岐している。スプール作動検出ライン73は、監視用スプール40を経由するように第1マルチコントロールバルブ4Aおよび第2マルチコントロールバルブ4Bに跨って延びており、タンクにつながっている。 The spool operation detection line 73 branches from the pilot pressure supply line 71. The spool operation detection line 73 extends across the first multi-control valve 4A and the second multi-control valve 4B so as to pass through the monitoring spool 40, and is connected to the tank.
 本実施形態では、監視用スプール40は、第1マルチコントロールバルブ4Aの旋回用スプール41と、第2マルチコントロールバルブ4Bのバケット用スプール44、ブーム用スプール45およびアーム用スプール46である。ただし、スプール作動検出ライン73が監視用スプール40を経由する順番は特に限定されないことは言うまでもない。また、監視用スプール40としては、第2マルチコントロールバルブ4Bのブーム用スプール45およびアーム用スプール46の代わりに、第1マルチコントロールバルブ4Aのブーム用スプール42およびアーム用スプール43が採用されてもよい。さらに、第1マルチコントロールバルブ4A又は第2マルチコントロールバルブ4Bがオプション用スプールを含む場合は、そのオプション用スプールが監視用スプール40に含まれてもよい。 In this embodiment, the monitoring spool 40 is the turning spool 41 of the first multi-control valve 4A, the bucket spool 44, the boom spool 45, and the arm spool 46 of the second multi-control valve 4B. However, it goes without saying that the order in which the spool operation detection line 73 passes through the monitoring spool 40 is not particularly limited. Further, as the monitoring spool 40, the boom spool 42 and the arm spool 43 of the first multi-control valve 4A may be employed instead of the boom spool 45 and the arm spool 46 of the second multi-control valve 4B. Good. Further, when the first multi-control valve 4A or the second multi-control valve 4B includes an option spool, the option spool may be included in the monitoring spool 40.
 図2に示すように、旋回用スプール41は、中立位置に位置するときでも作動したとき(中立位置から移動したとき)でも、スプール作動検出ライン73を遮断しないように構成されている。一方、旋回用スプール以外の監視用スプール40は、中立位置に位置するときにはスプール作動検出ライン73を遮断しないが、作動したとき(中立位置から移動したとき)にスプール作動検出ライン73を遮断するように構成されている。すなわち、スプール作動検出ライン73は、旋回操作弁51のみが操作されたときには遮断されないが、バケット操作弁53、ブーム操作弁54およびアーム操作弁52のいずれかが操作されると遮断される。 As shown in FIG. 2, the turning spool 41 is configured not to block the spool operation detection line 73 even when it is operated even when it is positioned at the neutral position (when it is moved from the neutral position). On the other hand, the monitoring spool 40 other than the turning spool does not block the spool operation detection line 73 when positioned at the neutral position, but blocks the spool operation detection line 73 when operated (when moved from the neutral position). It is configured. That is, the spool operation detection line 73 is not blocked when only the swing operation valve 51 is operated, but is blocked when any one of the bucket operation valve 53, the boom operation valve 54, and the arm operation valve 52 is operated.
 スプール作動検出ライン73の上流側の部分には、各スプールの作動状態によらず、パイロット圧供給ライン71の圧力が低下しすぎないようにするための絞り74が設けられている。また、スプール作動検出ライン73には、絞り74と第2マルチコントロールバルブ4Bの間に、スプール作動検出ライン73が遮断されたことを検出するための監視用圧力検出器75が設けられている。本実施形態では、監視用圧力検出器75として圧力センサが用いられている。ただし、監視用圧力検出器75は、スプール作動検出ライン73が遮断されたときにオンまたはオフとなる圧力スイッチであってもよい。 In the upstream portion of the spool operation detection line 73, a throttle 74 is provided to prevent the pressure of the pilot pressure supply line 71 from excessively decreasing regardless of the operation state of each spool. The spool operation detection line 73 is provided with a monitoring pressure detector 75 between the throttle 74 and the second multi-control valve 4B for detecting that the spool operation detection line 73 is blocked. In the present embodiment, a pressure sensor is used as the monitoring pressure detector 75. However, the monitoring pressure detector 75 may be a pressure switch that is turned on or off when the spool operation detection line 73 is interrupted.
 コントローラ8は、旋回用圧力検出器81および監視用圧力検出器75により、旋回操作弁51のみが操作されたと判定される場合は、パワーシフト圧Psが高くなるように比例弁72を制御する。これにより、第1油圧ポンプ21および第2油圧ポンプ22の吐出流量が減少する。その結果、旋回加速時に旋回油圧モータ24に供給される作動油の量を抑えて、エネルギーの無駄な消費を抑制することができる。なお、コントローラ8は、旋回の加速期間が過ぎれば、パワーシフト圧Psを元に戻すように比例弁72を制御してもよい。 When the turning pressure detector 81 and the monitoring pressure detector 75 determine that only the turning operation valve 51 has been operated, the controller 8 controls the proportional valve 72 so that the power shift pressure Ps is increased. Thereby, the discharge flow rates of the first hydraulic pump 21 and the second hydraulic pump 22 are reduced. As a result, the amount of hydraulic oil supplied to the turning hydraulic motor 24 during turning acceleration can be suppressed, and wasteful consumption of energy can be suppressed. Note that the controller 8 may control the proportional valve 72 so that the power shift pressure Ps is restored after the acceleration period of turning has passed.
 ここで、図9Bに、パワーシフト圧Psを上昇させたときの第1油圧ポンプ21の性能特性を二点鎖線Cで示す。なお、図中の実線Aは、図9Aの実線Aと同様に、パワーシフト圧Psが低い状況下での、双方の油圧ポンプ21,22に同じ負荷がかかったときの第1油圧ポンプ21の性能特性を示す。図9Bと図9Aの比較から、パワーシフト圧Psを上昇させることによって、旋回単独操作の場合に第1油圧ポンプ21の吐出流量の増加が抑えられることが分かる。 Here, in FIG. 9B, the performance characteristic of the first hydraulic pump 21 when the power shift pressure Ps is raised is indicated by a two-dot chain line C. Note that the solid line A in the figure is the same as the solid line A in FIG. 9A when the same load is applied to both the hydraulic pumps 21 and 22 under the situation where the power shift pressure Ps is low. Shows performance characteristics. From the comparison between FIG. 9B and FIG. 9A, it can be seen that by increasing the power shift pressure Ps, an increase in the discharge flow rate of the first hydraulic pump 21 can be suppressed in the case of a single swing operation.
 しかも、本実施形態では、旋回パイロット回路61に旋回用圧力検出器81を設けているので、第1供給ライン11に圧力検出器を設ける場合に比べて、安価な構成で上記の効果を得ることができる。また、本実施形態では、パワーシフト圧Psをレギュレータによる馬力制御に重畳して利用しているため、簡単な制御ロジックで、旋回単独操作の場合に第1油圧ポンプ21の吐出流量の増加が抑えられるという効果を得ることができる。更に、旋回加速の後半に進むにつれて旋回油圧モータ24に作用する負荷圧力が低下し、旋回速度を上昇させるには多くの流量が必要になるが、本実施形態では、パワーシフト圧Psの作用によって旋回単独操作時の第1油圧ポンプ21の吐出流量を一時的に減少させるものの、旋回加速の後半においては、第1油圧ポンプ21の吐出圧Pd1の低下に伴い、上述するレギュレータによる馬力制御の作用によって、第1油圧ポンプ21の吐出流量が自動的に増大する。これにより、旋回油圧モータ24には各旋回段階での負荷に応じた十分な流量の作動油が供給されるので、旋回時の操作フィーリングを損なうこともない。 In addition, in the present embodiment, since the turning pressure detector 81 is provided in the turning pilot circuit 61, the above-described effects can be obtained with an inexpensive configuration as compared with the case where the pressure detector is provided in the first supply line 11. Can do. Further, in the present embodiment, since the power shift pressure Ps is used while being superimposed on the horsepower control by the regulator, an increase in the discharge flow rate of the first hydraulic pump 21 is suppressed with simple control logic in the case of a single turning operation. Can be obtained. Furthermore, the load pressure acting on the swing hydraulic motor 24 decreases as it proceeds to the second half of the swing acceleration, and a large flow rate is required to increase the swing speed. In this embodiment, however, the power shift pressure Ps causes the flow rate to increase. Although the discharge flow rate of the first hydraulic pump 21 during the turning single operation is temporarily reduced, in the latter half of the turning acceleration, as the discharge pressure Pd1 of the first hydraulic pump 21 decreases, the horsepower control action by the regulator described above is performed. As a result, the discharge flow rate of the first hydraulic pump 21 automatically increases. As a result, the hydraulic hydraulic motor 24 is supplied with a sufficient amount of hydraulic oil corresponding to the load at each turning stage, so that the feeling of operation during turning is not impaired.
 さらには、旋回用スプール41が作動してもスプール作動検出ライン73を遮断しないように構成されているので、旋回パイロット回路61とスプール作動検出ライン73に圧力検出器を設けるだけで、旋回操作弁51のみが操作されたことを検出できる。すなわち、簡単な構成で旋回単独操作を検出することができる。 Further, since the spool operation detection line 73 is not cut off even when the turning spool 41 is operated, the turning operation valve is provided only by providing a pressure detector in the turning pilot circuit 61 and the spool operation detecting line 73. It can be detected that only 51 has been operated. That is, it is possible to detect a single turning operation with a simple configuration.
 <変形例>
 スプール作動検出ライン73は必ずしも旋回用スプール41を経由する必要はなく、旋回用スプール41に対するポート数を6としてもよい。この場合、スプール作動検出ライン73が第2マルチコントロールバルブ4Bのみに設けられていてもよい。
<Modification>
The spool operation detection line 73 does not necessarily pass through the turning spool 41, and the number of ports for the turning spool 41 may be six. In this case, the spool operation detection line 73 may be provided only in the second multi-control valve 4B.
 (第2実施形態)
 次に、図3および図4を参照して、本発明の第2実施形態に係る油圧駆動システムを説明する。なお、本実施形態ならびに後述する第3および第4実施形態において、第1実施形態と同一構成要素には同一符号を付し、重複した説明は省略する。
(Second Embodiment)
Next, with reference to FIG. 3 and FIG. 4, the hydraulic drive system which concerns on 2nd Embodiment of this invention is demonstrated. In the present embodiment and third and fourth embodiments to be described later, the same components as those in the first embodiment are denoted by the same reference numerals, and redundant description is omitted.
 本実施形態では、図4に示すように、旋回用スプール41が、作動したときにスプール作動検出ライン73を遮断するように構成されている。すなわち、旋回操作弁51、バケット操作弁53、ブーム操作弁54およびアーム操作弁52(操作弁51~54については図1参照)のいずれが操作されても、スプール作動検出ライン73が遮断される。 In this embodiment, as shown in FIG. 4, when the turning spool 41 is operated, the spool operation detection line 73 is cut off. That is, the spool operation detection line 73 is shut off regardless of which of the swing operation valve 51, the bucket operation valve 53, the boom operation valve 54, and the arm operation valve 52 (see FIG. 1 for the operation valves 51 to 54). .
 このため、旋回操作弁51のみが操作されたことを検出するための構成として、図3に示すように、旋回用スプール41以外の監視用スプール40を作動させるパイロット回路62~64のいずれかにおいてパイロット圧が立ったことを検出するための非旋回用圧力検出器82が設けられている。非旋回用圧力検出器82は、パイロット回路62~64の全てのパイロットライン(62A~64B)のうちでパイロット圧が最も高いもののパイロット圧を選択的に検出できるように構成されている。本実施形態では、非旋回用圧力検出器82として圧力センサが用いられている。ただし、非旋回用圧力検出器82は、パイロット回路62~64のいずれかにおいてパイロット圧が立ったときにオンまたはオフとなる圧力スイッチであってもよい。 Therefore, as a configuration for detecting that only the turning operation valve 51 is operated, as shown in FIG. 3, in any of the pilot circuits 62 to 64 for operating the monitoring spool 40 other than the turning spool 41. A non-turning pressure detector 82 is provided for detecting that the pilot pressure has been established. The non-turning pressure detector 82 is configured to selectively detect the pilot pressure of the highest pilot pressure among all the pilot lines (62A to 64B) of the pilot circuits 62 to 64. In the present embodiment, a pressure sensor is used as the non-turning pressure detector 82. However, the non-turning pressure detector 82 may be a pressure switch that is turned on or off when a pilot pressure is established in any of the pilot circuits 62 to 64.
 本実施形態でも、第1実施形態と同様に、コントローラ8が、旋回用スプール41のみが作動したときに、パワーシフト圧Psが高くなって第1油圧ポンプ21および第2油圧ポンプ22の吐出流量が減少するように比例弁72を制御する。これにより、第1実施形態と同様の効果を得ることができる。 Also in this embodiment, similarly to the first embodiment, when only the turning spool 41 is operated, the controller 8 increases the power shift pressure Ps and the discharge flow rates of the first hydraulic pump 21 and the second hydraulic pump 22. The proportional valve 72 is controlled so as to decrease. Thereby, the effect similar to 1st Embodiment can be acquired.
 また、本実施形態では、旋回用スプール41が作動したときにスプール作動検出ライン73を遮断するように構成されているので、通常の構造の旋回用スプールを用いて旋回単独操作を検出することができる。換言すれば、既存の建設機械に組み込まれた油圧駆動システムを、本実施形態の油圧駆動システムに安価に改造することができる。 Further, in the present embodiment, since the spool operation detection line 73 is cut off when the turning spool 41 is operated, it is possible to detect a turning single operation using a turning spool having a normal structure. it can. In other words, the hydraulic drive system incorporated in the existing construction machine can be modified at low cost to the hydraulic drive system of the present embodiment.
 (第3実施形態)
 次に、図5および図6を参照して、本発明の第3実施形態に係る油圧駆動システム1Bを説明する。本実施形態では、旋回操作だけでなく、必要流量が少ないバケットアウト操作およびブーム下げ操作も検出することができる構成が採用されている。そして、コントローラ8は、旋回用スプール41のみが作動したときだけでなく、旋回用スプール41が作動し、かつ、バケット用スプール44および/またはブーム用スプール45が必要流量が少ない方向(バケットアウトおよび/またはブーム下げの方向)に作動したときも、パワーシフト圧Psが高くなって第1油圧ポンプ21および第2油圧ポンプ22の吐出流量が減少するように比例弁72を制御する。
(Third embodiment)
Next, with reference to FIGS. 5 and 6, a hydraulic drive system 1B according to a third embodiment of the present invention will be described. In this embodiment, the structure which can detect not only turning operation but the bucket out operation and boom lowering operation with small required flow volume is employ | adopted. Then, the controller 8 is operated not only when only the turning spool 41 is operated, but also when the turning spool 41 is operated and the bucket spool 44 and / or the boom spool 45 has a smaller required flow rate (bucket out and Also, when operated in the direction of lowering the boom, the proportional valve 72 is controlled so that the power shift pressure Ps increases and the discharge flow rates of the first hydraulic pump 21 and the second hydraulic pump 22 decrease.
 具体的には、図6に示すように、バケット用スプール44が、バケットアウトの方向に作動したときでもスプール作動検出ライン73を遮断しないように構成されている。また、バケットパイロット回路63には、バケットアウト用ライン63Bのパイロット圧が立ったことを検出するためのバケットアウト用圧力検出器83が設けられている。本実施形態では、バケットアウト用圧力検出器83として圧力センサが用いられている。ただし、バケットアウト用圧力検出器83は、バケットアウト用ライン63Bのパイロット圧が立ったときにオンまたはオフとなる圧力スイッチであってもよい。 More specifically, as shown in FIG. 6, the bucket spool 44 is configured not to block the spool operation detection line 73 even when it operates in the bucket-out direction. Further, the bucket pilot circuit 63 is provided with a bucket-out pressure detector 83 for detecting that the pilot pressure in the bucket-out line 63B has risen. In the present embodiment, a pressure sensor is used as the bucket-out pressure detector 83. However, the bucket-out pressure detector 83 may be a pressure switch that is turned on or off when the pilot pressure of the bucket-out line 63B is raised.
 さらには、ブーム用スプール45が、ブーム下げの方向に作動したときでもスプール作動検出ライン73を遮断しないように構成されている。また、ブームパイロット回路64には、ブーム下げ用ライン64Bのパイロット圧が立ったことを検出するためのブーム下げ用圧力検出器84が設けられている。本実施形態では、ブーム下げ用圧力検出器84として圧力センサが用いられている。ただし、ブーム下げ用圧力検出器84は、ブーム下げ用ライン64Bのパイロット圧が立ったときにオンまたはオフとなる圧力スイッチであってもよい。 Furthermore, it is configured so that the spool operation detection line 73 is not blocked even when the boom spool 45 is operated in the boom lowering direction. Further, the boom pilot circuit 64 is provided with a boom lowering pressure detector 84 for detecting that the pilot pressure of the boom lowering line 64B has been raised. In the present embodiment, a pressure sensor is used as the boom lowering pressure detector 84. However, the boom lowering pressure detector 84 may be a pressure switch that is turned on or off when the pilot pressure of the boom lowering line 64B is raised.
 そして、コントローラ8は、次の4つの場合に、パワーシフト圧Psが高くなるように比例弁72を制御する。これにより、第1油圧ポンプ21および第2油圧ポンプ22の各々のポンプの吐出圧に対する吐出流量が減少する。その結果、旋回加速時に旋回油圧モータ24に供給される作動油の量を抑えて、エネルギーの無駄な消費を抑制することができる。なお、コントローラ8は、旋回の加速期間が過ぎれば、パワーシフト圧Psを元に戻すように比例弁72を制御してもよい。 And the controller 8 controls the proportional valve 72 so that the power shift pressure Ps becomes high in the following four cases. Thereby, the discharge flow rate with respect to the discharge pressure of each of the first hydraulic pump 21 and the second hydraulic pump 22 decreases. As a result, the amount of hydraulic oil supplied to the turning hydraulic motor 24 during turning acceleration can be suppressed, and wasteful consumption of energy can be suppressed. Note that the controller 8 may control the proportional valve 72 so that the power shift pressure Ps is restored after the acceleration period of turning has passed.
 上述した4つの場合の1つ目は、旋回用圧力検出器81によるパイロット圧検出ならびに監視用圧力検出器75、バケットアウト用圧力検出器83およびブーム下げ用圧力検出器84の非検出によって、旋回操作弁51のみが操作されたと判定される場合である。2つ目は、旋回用圧力検出器81およびバケットアウト用圧力検出器83によるパイロット圧検出ならびに監視用圧力検出器75およびブーム下げ用圧力検出器84の非検出によって、旋回操作弁51が操作され、かつ、バケット操作弁53がバケットアウト方向に操作されたと判定される場合である。3つ目は、旋回用圧力検出器81およびブーム下げ用圧力検出器84によるパイロット圧検出ならびに監視用圧力検出器75およびバケットアウト用圧力検出器83の非検出によって、旋回操作弁51が操作され、かつ、ブーム操作弁54がブーム下げ方向に操作されたと判定される場合である。4つ目は、旋回用圧力検出器81、バケットアウト用圧力検出器83およびブーム下げ用圧力検出器84によるパイロット圧検出ならびに監視用圧力検出器75の非検出によって、旋回操作弁51が操作され、かつ、バケット操作弁53がバケットアウト方向に操作され、かつ、ブーム操作弁54がブーム下げ方向に操作されたと判定される場合である。 The first of the four cases described above is based on the pilot pressure detection by the turning pressure detector 81 and the non-detection of the monitoring pressure detector 75, the bucket-out pressure detector 83, and the boom lowering pressure detector 84. This is a case where it is determined that only the operation valve 51 has been operated. Second, the swing operation valve 51 is operated by the pilot pressure detection by the swing pressure detector 81 and the bucket-out pressure detector 83 and the non-detection of the monitoring pressure detector 75 and the boom lowering pressure detector 84. And it is a case where it determines with the bucket operation valve 53 having been operated in the bucket out direction. Third, the turning operation valve 51 is operated by detecting the pilot pressure by the turning pressure detector 81 and the boom lowering pressure detector 84 and by not detecting the monitoring pressure detector 75 and the bucket-out pressure detector 83. And it is a case where it determines with the boom operation valve 54 having been operated by the boom lowering direction. Fourth, the swing operation valve 51 is operated by the pilot pressure detection by the swing pressure detector 81, the bucket-out pressure detector 83, and the boom lowering pressure detector 84 and the non-detection of the monitoring pressure detector 75. In this case, it is determined that the bucket operation valve 53 is operated in the bucket-out direction and the boom operation valve 54 is operated in the boom lowering direction.
 本実施形態の構成によれば、旋回単独操作のときだけでなく、旋回とブーム下げの同時操作、旋回とバケットアウトの同時操作、旋回とブーム下げとバケットアウトの同時操作という頻繁に行われる操作のときにも、旋回加速時のエネルギーの無駄な消費を抑制することができる。 According to the configuration of the present embodiment, not only during turning operation alone, but also frequently performed operations such as simultaneous operation of turning and boom lowering, simultaneous operation of turning and bucket out, and simultaneous operation of turning and boom lowering and bucket out. In this case, it is possible to suppress wasteful consumption of energy during acceleration of turning.
 <変形例>
 バケットアウト操作およびブーム下げ操作は、必ずしも双方が検出可能である必要はなく、いずれか一方が検出可能であってもよい。
<Modification>
Both the bucket-out operation and the boom lowering operation do not necessarily need to be detectable, and either one may be detectable.
 また、第2実施形態のように、図7に示す非旋回用圧力検出器82を採用すれば、旋回用スプール41、バケット用スプール44およびブーム用スプール45を、図4に示すような通常の構造(作動したときにスプール作動検出ライン73を遮断する構造)に変更することができる。この場合、本実施形態ではバケットアウト用圧力検出器83およびブーム下げ用圧力検出器84が設けられているため、図7に示すように、非旋回用圧力検出器82が選択的にパイロット圧を検出するパイロットラインからブーム下げ用ライン64Bおよびバケットアウト用ライン63Bが除かれていてもよい。 Further, if the non-turning pressure detector 82 shown in FIG. 7 is employed as in the second embodiment, the turning spool 41, the bucket spool 44, and the boom spool 45 are replaced with a normal one as shown in FIG. It can be changed to a structure (a structure that shuts off the spool operation detection line 73 when it is operated). In this case, since the bucket-out pressure detector 83 and the boom lowering pressure detector 84 are provided in this embodiment, as shown in FIG. 7, the non-turning pressure detector 82 selectively applies the pilot pressure. The boom lowering line 64B and the bucket out line 63B may be removed from the pilot line to be detected.
 (第4実施形態)
 次に、図8を参照して、本発明の第4実施形態に係る油圧駆動システム1Cを説明する。本実施形態では、全ての監視用スプール40が図4に示すような通常の構造(作動したときにスプール作動検出ライン73を遮断する構造)を有している。
(Fourth embodiment)
Next, with reference to FIG. 8, a hydraulic drive system 1C according to a fourth embodiment of the present invention will be described. In this embodiment, all the monitoring spools 40 have a normal structure as shown in FIG. 4 (a structure that shuts off the spool operation detection line 73 when operated).
 また、本実施形態では、第3実施形態で説明したバケットアウト用圧力検出器83およびブーム下げ用圧力検出器84に加えて、バケットパイロット回路63のバケットイン用ライン63Aにバケットイン用圧力検出器85が設けられ、ブームパイロット回路64のブーム上げ用ライン64Aにブーム上げ用圧力検出器86が設けられ、アームパイロット回路62(アームイン用ライン62Aおよびアームアウト用ライン62B)にアーム用圧力検出器87が設けられている。バケットイン用圧力検出器85は、バケットイン用ライン63Aのパイロット圧が立ったことを検出するためのものであり、ブーム上げ用圧力検出器86は、ブーム上げ用ライン64Aのパイロット圧が立ったことを検出するためのものであり、アーム用圧力検出器87は、アームパイロット回路62(アームイン用ライン62Aおよびアームアウト用ライン62B)のパイロット圧が立ったことを検出するためのものである。 In this embodiment, in addition to the bucket-out pressure detector 83 and the boom lowering pressure detector 84 described in the third embodiment, the bucket-in pressure detector is connected to the bucket-in line 63A of the bucket pilot circuit 63. 85, a boom raising pressure detector 86 is provided on the boom raising line 64A of the boom pilot circuit 64, and an arm pressure detector 87 is provided on the arm pilot circuit 62 (arm-in line 62A and arm-out line 62B). Is provided. The bucket-in pressure detector 85 is for detecting that the pilot pressure in the bucket-in line 63A has been established, and the boom raising pressure detector 86 has been established in the boom raising line 64A. The arm pressure detector 87 is for detecting that the pilot pressure of the arm pilot circuit 62 (arm-in line 62A and arm-out line 62B) has been established.
 本実施形態でも、第3実施形態と同様に、旋回操作だけでなく、必要流量が少ないバケットアウト操作およびブーム下げ操作も検出することができる。従って、本実施形態でも、第3実施形態と同様の効果を得ることができる。また、本実施形態では、全ての操作弁51~54のパイロット回路61~64に圧力検出器が設けられているので、監視用スプール40として、通常の構造の旋回用スプール41、バケット用スプール44、ブーム用スプール45およびアーム用スプール46を用いても、旋回単独操作を検出することができる。その結果、既存の建設機械に組み込まれた油圧駆動システムを、本実施形態の油圧駆動システムに安価に改造することができる。 In this embodiment, as in the third embodiment, not only a turning operation but also a bucket-out operation and a boom lowering operation with a small required flow rate can be detected. Therefore, the present embodiment can provide the same effects as those of the third embodiment. In this embodiment, since the pressure detectors are provided in the pilot circuits 61 to 64 of all the operation valves 51 to 54, the monitoring spool 40 is a swirl spool 41 having a normal structure, and a bucket spool 44. Even if the boom spool 45 and the arm spool 46 are used, it is possible to detect the turning operation alone. As a result, the hydraulic drive system incorporated in the existing construction machine can be retrofitted to the hydraulic drive system of the present embodiment at a low cost.
 なお、本実施形態では、第2マルチコントロールバルブ4Bのアーム用スプール46が監視用スプール40であるが、第1実施形態で説明したように、第1マルチコントロールバルブ4Aのアーム用スプール43が監視用スプール40であってもよいことは言うまでもない。 In this embodiment, the arm spool 46 of the second multi-control valve 4B is the monitoring spool 40. However, as described in the first embodiment, the arm spool 43 of the first multi-control valve 4A is monitored. Needless to say, the spool 40 may be used.
 また、旋回単独操作および旋回とブーム下げの同時操作のみを検出する場合には、バケットパイロット回路63に、バケットアウト用圧力検出器83およびバケットイン用圧力検出器85の代わりに、バケットイン用ライン63Aおよびバケットアウト用ライン63Bのうちでパイロット圧が高い方のパイロット圧を選択的に検出できるように構成された圧力検出器(図示せず)が設けられてもよい。同様に、旋回単独操作および旋回とバケットアウトの同時操作のみを検出する場合には、ブームパイロット回路64に、ブーム下げ用圧力検出器84およびブーム上げ用圧力検出器86の代わりに、ブーム上げ用ライン64Aおよびブーム下げ用ライン64Bのうちでパイロット圧が高い方のパイロット圧を選択的に検出できるように構成された圧力検出器(図示せず)が設けられてもよい。 Further, in the case of detecting only the turning single operation and the simultaneous turning and boom lowering operation, the bucket pilot circuit 63 uses a bucket-in line instead of the bucket-out pressure detector 83 and the bucket-in pressure detector 85. A pressure detector (not shown) configured to selectively detect a pilot pressure having a higher pilot pressure among 63A and the bucket-out line 63B may be provided. Similarly, in the case of detecting only a single turning operation and a simultaneous turning and bucket-out operation, the boom pilot circuit 64 uses a boom raising pressure detector 84 and a boom raising pressure detector 86 instead of the boom raising pressure detector 84. A pressure detector (not shown) configured to selectively detect the pilot pressure with the higher pilot pressure out of the line 64A and the boom lowering line 64B may be provided.
 (その他の実施形態)
 前記第1実施形態ないし第4実施形態において、第1および第2油圧ポンプ21,22の吐出流量の制御方式は、必ずしもネガコン方式である必要はなく、ポジティブコントロール方式であってもよい。すなわち、第1および第2レギュレータ3A,3Bはネガコン用ピストン33の代わりにポジコン用ピストンを有してもよい。あるいは、流量制御を電気的に行う方式(いわゆる電気ポジコン)であってもよい。また、第1および第2油圧ポンプ21,22の吐出流量の制御方式は、ロードセンシング方式であってもよい。
(Other embodiments)
In the first to fourth embodiments, the discharge flow rate control method of the first and second hydraulic pumps 21 and 22 is not necessarily the negative control method, and may be the positive control method. That is, the first and second regulators 3 </ b> A and 3 </ b> B may have a positive control piston instead of the negative control piston 33. Or the system (what is called an electric positive control) which performs flow control electrically may be used. Further, the control method of the discharge flow rate of the first and second hydraulic pumps 21 and 22 may be a load sensing method.
 本発明の油圧駆動システムは、種々の建設機械に対して有用である。 The hydraulic drive system of the present invention is useful for various construction machines.
 1A~1C 油圧駆動システム
 21 第1油圧ポンプ
 22 第2油圧ポンプ
 24 旋回油圧モータ
 3A 第1レギュレータ
 3B 第2レギュレータ
 4A 第1マルチコントロールバルブ
 4B 第2マルチコントロールバルブ
 40 監視用スプール
 41 旋回用スプール
 44 バケット用スプール
 42,45 ブーム用スプール
 61~64 パイロット回路
 63B バケットアウト用ライン
 64B ブーム下げ用ライン
 72 比例弁
 73 スプール作動検出ライン
 75 監視用圧力検出器
 8  コントローラ
 81 旋回用圧力検出器
 82 非旋回用圧力検出器
 83 バケットアウト用圧力検出器
 84 ブーム下げ用圧力検出器
DESCRIPTION OF SYMBOLS 1A-1C Hydraulic drive system 21 1st hydraulic pump 22 2nd hydraulic pump 24 Turning hydraulic motor 3A 1st regulator 3B 2nd regulator 4A 1st multi-control valve 4B 2nd multi-control valve 40 Monitoring spool 41 Turning spool 44 Bucket Spool 42, 45 Boom spool 61-64 Pilot circuit 63B Bucket out line 64B Boom lowering line 72 Proportional valve 73 Spool operation detection line 75 Monitoring pressure detector 8 Controller 81 Swing pressure detector 82 Non-turning pressure Detector 83 Bucket-out pressure detector 84 Boom lowering pressure detector

Claims (5)

  1.  旋回油圧モータを具備する建設機械用の油圧駆動システムであって、
     エンジンにより駆動されて傾転角に応じた流量の作動油を吐出する第1油圧ポンプおよび第2油圧ポンプと、
     前記第1油圧ポンプと接続された、前記旋回油圧モータを制御するための旋回用スプールを含む第1マルチコントロールバルブと、
     前記第2油圧ポンプと接続された第2マルチコントロールバルブと、
     前記第1油圧ポンプおよび前記第2油圧ポンプの吐出圧ならびにパワーシフト圧に応じて、それらが高くなるほど前記第1ポンプの吐出流量が減少するように前記第1油圧ポンプの傾転角を調整する第1レギュレータと、
     前記第2油圧ポンプおよび前記第1油圧ポンプの吐出圧ならびに前記パワーシフト圧に応じて、それらが高くなるほど前記第2ポンプの吐出流量が減少するように前記第2油圧ポンプの傾転角を調整する第2レギュレータと、
     前記第1レギュレータおよび前記第2レギュレータに導かれる前記パワーシフト圧を設定する比例弁と、
     前記旋回用スプールのみが作動したとき、または前記旋回用スプールが作動し、かつ、前記第2マルチコントロールバルブに含まれる1つまたは複数のスプールが必要流量が少ない方向に作動したときに、前記パワーシフト圧が高くなって前記第1油圧ポンプおよび前記第2油圧ポンプの吐出流量が減少するように前記比例弁を制御するコントローラと、を備える、油圧駆動システム。
    A hydraulic drive system for a construction machine having a swing hydraulic motor,
    A first hydraulic pump and a second hydraulic pump that are driven by an engine to discharge hydraulic oil at a flow rate according to a tilt angle;
    A first multi-control valve connected to the first hydraulic pump and including a swing spool for controlling the swing hydraulic motor;
    A second multi-control valve connected to the second hydraulic pump;
    In accordance with the discharge pressure and power shift pressure of the first hydraulic pump and the second hydraulic pump, the tilt angle of the first hydraulic pump is adjusted so that the discharge flow rate of the first pump decreases as they increase. A first regulator;
    In accordance with the discharge pressure of the second hydraulic pump and the first hydraulic pump and the power shift pressure, the tilt angle of the second hydraulic pump is adjusted so that the discharge flow rate of the second pump decreases as they increase. A second regulator that
    A proportional valve for setting the power shift pressure led to the first regulator and the second regulator;
    When only the turning spool is operated, or when the turning spool is operated and one or more spools included in the second multi-control valve are operated in a direction where the required flow rate is low, the power And a controller that controls the proportional valve such that a discharge pressure of the first hydraulic pump and the second hydraulic pump decreases as a shift pressure increases.
  2.  前記旋回用スプールを含む監視用スプールを経由するように前記第1マルチコントロールバルブおよび前記第2マルチコントロールバルブに跨って延びるスプール作動検出ラインと、
     前記スプール作動検出ラインが遮断されたことを検出するための監視用圧力検出器と、
     前記旋回用スプールを作動させるパイロット回路のパイロット圧が立ったことを検出するための旋回用圧力検出器と、をさらに備え、
     前記旋回用スプールは、作動したときでも前記スプール作動検出ラインを遮断しないように構成されている、請求項1に記載の油圧駆動システム。
    A spool operation detection line extending across the first multi-control valve and the second multi-control valve so as to pass through the monitoring spool including the turning spool;
    A monitoring pressure detector for detecting that the spool operation detection line is shut off;
    A turning pressure detector for detecting that a pilot pressure of a pilot circuit for operating the turning spool has been established,
    2. The hydraulic drive system according to claim 1, wherein the turning spool is configured not to interrupt the spool operation detection line even when the spool is operated. 3.
  3.  前記旋回用スプールを含む監視用スプールを経由するように前記第1マルチコントロールバルブおよび前記第2マルチコントロールバルブに跨って延びるスプール作動検出ラインと、
     前記旋回用スプールを作動させるパイロット回路のパイロット圧が立ったことを検出するための旋回用圧力検出器と、
     前記旋回用スプール以外の前記監視用スプールを作動させるパイロット回路のいずれかにおいてパイロット圧が立ったことを検出するための非旋回用圧力検出器と、をさらに備え、
     前記旋回用スプールは、作動したときに前記スプール作動検出ラインを遮断するように構成されている、請求項1に記載の油圧駆動システム。
    A spool operation detection line extending across the first multi-control valve and the second multi-control valve so as to pass through the monitoring spool including the turning spool;
    A turning pressure detector for detecting that a pilot pressure of a pilot circuit for operating the turning spool has been established;
    A non-turning pressure detector for detecting that a pilot pressure has been established in any of the pilot circuits that operate the monitoring spool other than the turning spool;
    The hydraulic drive system according to claim 1, wherein the turning spool is configured to shut off the spool operation detection line when operated.
  4.  前記建設機械は、バケット、アームおよびブームを備える油圧ショベルであり、
     前記第2マルチコントロールバルブは、前記監視用スプールとして、バケット用スプールとブーム用スプールを含み、
     前記バケット用スプールは、バケットアウトの方向に作動したときでも前記スプール作動検出ラインを遮断しないように構成されており、
     前記ブーム用スプールは、ブーム下げの方向に作動したときでも前記スプール作動検出ラインを遮断しないように構成されており、
     前記バケット用スプールを作動させるパイロット回路におけるバケットアウト用ラインのパイロット圧が立ったことを検出するためのバケットアウト用圧力検出器と、
     前記ブーム用スプールを作動させるパイロット回路におけるブーム下げ用ラインのパイロット圧が立ったことを検出するためのブーム下げ用圧力検出器と、
    をさらに備える、請求項2または3に記載の油圧駆動システム。
    The construction machine is a hydraulic excavator including a bucket, an arm and a boom,
    The second multi-control valve includes a bucket spool and a boom spool as the monitoring spool,
    The bucket spool is configured not to interrupt the spool operation detection line even when operated in the bucket-out direction,
    The boom spool is configured not to block the spool operation detection line even when operated in a boom lowering direction.
    A bucket-out pressure detector for detecting that the pilot pressure of the bucket-out line in the pilot circuit for operating the bucket spool has been established;
    A boom lowering pressure detector for detecting that the pilot pressure of the boom lowering line in the pilot circuit for operating the boom spool is raised;
    The hydraulic drive system according to claim 2, further comprising:
  5.  前記建設機械は、バケット、アームおよびブームを備える油圧ショベルであり、
     前記旋回用スプールを含む監視用スプールを経由するように前記第1マルチコントロールバルブおよび前記第2マルチコントロールバルブに跨って延びるスプール作動検出ラインをさらに備え、
     前記第1マルチコントロールバルブと前記第2マルチコントロールバルブのどちらかは、前記監視用スプールとして、アーム用スプールを含み、
     前記第2マルチコントロールバルブは、前記監視用スプールとして、バケット用スプールとブーム用スプールを含み、
     前記旋回用スプール、前記アーム用スプール、前記バケット用スプールおよび前記ブーム用スプールは、作動したときに前記スプール作動検出ラインを遮断するように構成されており、
     前記旋回用スプール、前記アーム用スプール、前記バケット用スプールおよび前記ブーム用スプールを作動させるパイロット回路のそれぞれには、当該パイロット回路のパイロット圧が立ったことを検出するための圧力検出器が設けられている、請求項1に記載の油圧駆動システム。
    The construction machine is a hydraulic excavator including a bucket, an arm and a boom,
    A spool operation detection line extending across the first multi-control valve and the second multi-control valve so as to pass through the monitoring spool including the turning spool;
    Either the first multi-control valve or the second multi-control valve includes an arm spool as the monitoring spool,
    The second multi-control valve includes a bucket spool and a boom spool as the monitoring spool,
    The swing spool, the arm spool, the bucket spool, and the boom spool are configured to shut off the spool operation detection line when operated.
    Each of the pilot circuits for operating the turning spool, the arm spool, the bucket spool, and the boom spool is provided with a pressure detector for detecting that the pilot pressure of the pilot circuit has been established. The hydraulic drive system according to claim 1.
PCT/JP2014/005092 2013-10-15 2014-10-07 Hydraulic drive system WO2015056422A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
GB1606883.5A GB2534517B (en) 2013-10-15 2014-10-07 Hydraulic drive system
CN201480056725.0A CN105612358B (en) 2013-10-15 2014-10-07 Hydraulic drive system

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2013214606A JP6106063B2 (en) 2013-10-15 2013-10-15 Hydraulic drive system
JP2013-214606 2013-10-15

Publications (1)

Publication Number Publication Date
WO2015056422A1 true WO2015056422A1 (en) 2015-04-23

Family

ID=52827882

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2014/005092 WO2015056422A1 (en) 2013-10-15 2014-10-07 Hydraulic drive system

Country Status (4)

Country Link
JP (1) JP6106063B2 (en)
CN (1) CN105612358B (en)
GB (1) GB2534517B (en)
WO (1) WO2015056422A1 (en)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6378734B2 (en) * 2016-10-27 2018-08-22 川崎重工業株式会社 Hydraulic excavator drive system
JP2018128127A (en) * 2017-02-10 2018-08-16 川崎重工業株式会社 Liquid pressure drive system
JP6912947B2 (en) * 2017-06-14 2021-08-04 川崎重工業株式会社 Hydraulic system
JP6731387B2 (en) * 2017-09-29 2020-07-29 株式会社日立建機ティエラ Hydraulic drive for construction machinery
JP6632597B2 (en) * 2017-12-25 2020-01-22 株式会社クボタ Working machine hydraulic system
JP2021038787A (en) * 2019-09-03 2021-03-11 川崎重工業株式会社 Hydraulic system of construction machine

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62240485A (en) * 1986-04-10 1987-10-21 Yutani Heavy Ind Ltd Horsepower distributing device for hydraulic pump for working machine
JPH02129401A (en) * 1988-11-09 1990-05-17 Yutani Heavy Ind Ltd Horse power allocating device for hydraulic pump
JPH11101183A (en) * 1997-09-29 1999-04-13 Hitachi Constr Mach Co Ltd Torque control device for hydraulic pump for hydraulic construction machine
JP2005344430A (en) * 2004-06-04 2005-12-15 Sumitomo (Shi) Construction Machinery Manufacturing Co Ltd Turning independent operation detection circuit of hydraulic shovel
JP2008196165A (en) * 2007-02-09 2008-08-28 Hitachi Constr Mach Co Ltd Pump torque control device of hydraulic construction machinery

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4151597B2 (en) * 2004-03-31 2008-09-17 コベルコ建機株式会社 Hydraulic control circuit and construction machinery
US8510000B2 (en) * 2008-03-26 2013-08-13 Kayaba Industry Co., Ltd. Hybrid construction machine
JP5461234B2 (en) * 2010-02-26 2014-04-02 カヤバ工業株式会社 Construction machine control equipment
CN103470557B (en) * 2013-09-05 2015-09-16 南京工业大学 Hydraulic rotary braking energy-saving control system
JP6334885B2 (en) * 2013-10-15 2018-05-30 川崎重工業株式会社 Hydraulic drive system
JP6088396B2 (en) * 2013-10-15 2017-03-01 川崎重工業株式会社 Hydraulic drive system

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62240485A (en) * 1986-04-10 1987-10-21 Yutani Heavy Ind Ltd Horsepower distributing device for hydraulic pump for working machine
JPH02129401A (en) * 1988-11-09 1990-05-17 Yutani Heavy Ind Ltd Horse power allocating device for hydraulic pump
JPH11101183A (en) * 1997-09-29 1999-04-13 Hitachi Constr Mach Co Ltd Torque control device for hydraulic pump for hydraulic construction machine
JP2005344430A (en) * 2004-06-04 2005-12-15 Sumitomo (Shi) Construction Machinery Manufacturing Co Ltd Turning independent operation detection circuit of hydraulic shovel
JP2008196165A (en) * 2007-02-09 2008-08-28 Hitachi Constr Mach Co Ltd Pump torque control device of hydraulic construction machinery

Also Published As

Publication number Publication date
CN105612358A (en) 2016-05-25
CN105612358B (en) 2017-02-08
JP6106063B2 (en) 2017-03-29
GB2534517A (en) 2016-07-27
GB2534517B (en) 2020-01-15
JP2015078714A (en) 2015-04-23

Similar Documents

Publication Publication Date Title
JP6220228B2 (en) Hydraulic drive system for construction machinery
US7497080B2 (en) Hydraulic controlling device of working machine
WO2015056422A1 (en) Hydraulic drive system
JP6220227B2 (en) Hydraulic excavator drive system
KR102460499B1 (en) shovel
JP6514522B2 (en) Hydraulic drive system of unloading valve and hydraulic shovel
JP6776334B2 (en) Excavator and control valve for excavator
WO2015056421A1 (en) Hydraulic drive system
WO2015056423A1 (en) Hydraulic drive system
KR20200035951A (en) Shovel
JP2010014244A (en) Construction machinery
WO2016092809A1 (en) Hydraulic drive system for construction machinery
JP5622243B2 (en) Fluid pressure control circuit and work machine
JP7029939B2 (en) Construction machinery drive system
JP2008002505A (en) Energy saving device for construction machine
US20190017247A1 (en) Excavator and control valve for excavator
KR20090028874A (en) Hydraulic circuit for heavy equipment
JP6763326B2 (en) Hydraulic circuit
WO2016153014A1 (en) Shovel and method for driving shovel

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 14854439

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 201606883

Country of ref document: GB

Kind code of ref document: A

Free format text: PCT FILING DATE = 20141007

122 Ep: pct application non-entry in european phase

Ref document number: 14854439

Country of ref document: EP

Kind code of ref document: A1