CN110953197A - Power control hydraulic system and crane - Google Patents
Power control hydraulic system and crane Download PDFInfo
- Publication number
- CN110953197A CN110953197A CN201911338964.6A CN201911338964A CN110953197A CN 110953197 A CN110953197 A CN 110953197A CN 201911338964 A CN201911338964 A CN 201911338964A CN 110953197 A CN110953197 A CN 110953197A
- Authority
- CN
- China
- Prior art keywords
- valve
- oil
- flow control
- control valve
- port
- Prior art date
- Legal status (The legal status 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 status listed.)
- Granted
Links
- 238000006073 displacement reaction Methods 0.000 claims abstract description 58
- 230000007246 mechanism Effects 0.000 claims abstract description 33
- 238000004891 communication Methods 0.000 claims description 9
- 239000003921 oil Substances 0.000 description 196
- 238000012423 maintenance Methods 0.000 description 7
- 238000013461 design Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 4
- 239000010720 hydraulic oil Substances 0.000 description 4
- 238000000034 method Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 230000008439 repair process Effects 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/08—Servomotor systems without provision for follow-up action; Circuits therefor with only one servomotor
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
- F15B13/04—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/205—Systems with pumps
- F15B2211/2053—Type of pump
- F15B2211/20538—Type of pump constant capacity
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/205—Systems with pumps
- F15B2211/20576—Systems with pumps with multiple pumps
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The invention relates to a crane hydraulic system and discloses a power control hydraulic system which comprises a first fixed displacement pump, a second fixed displacement pump, an operating valve, a plurality of load executing mechanisms, a flow control valve and a control valve, wherein the operating valve is respectively connected with each load executing mechanism, the first fixed displacement pump and the second fixed displacement pump are respectively connected with an oil inlet of the operating valve so as to supply oil to each load executing mechanism through the operating valve, the flow control valve comprises a first oil outlet connected with the oil inlet of the operating valve, a second oil outlet connected with a main oil return oil path and a first oil inlet connected with the first fixed displacement pump, and the opening degree of a valve port of the second oil outlet of the flow control valve can be controlled so as to adjust the flow input into each load executing mechanism. The invention also discloses a crane. The invention can adjust the power required by the load and meet the requirements of various working conditions on the output power.
Description
Technical Field
The invention relates to a crane hydraulic system, in particular to a power control hydraulic system, and further relates to a crane.
Background
The metering pump confluence hydraulic system of the truck crane consists of a multiple gear pump, a control valve group and a load, and the running speed of a main machine is improved through confluence of the multiple gear pump.
The gear pumps used by the truck crane are all constant-displacement gear pumps, and in order to improve the running speed of the system, a double-pump confluence technology is mostly adopted. The double-pump confluence technology is a technology for improving the operating speed of a certain working condition of a hydraulic system by combining the output flows of two pumps into one path before, on or behind a control valve group and then acting on a load together.
Specifically, fig. 1 shows a conventional double-pump confluence hydraulic system for a crane, in which the flows output by a first fixed displacement pump 1 and a second fixed displacement pump 2 respectively flow together through a first check valve 71 and a second check valve 72 on a pilot valve 3, and then flow together through a multi-way valve 33 and a corresponding pressure compensation valve 34, and then act on a corresponding load actuator 4 through a corresponding balance valve 8, so as to achieve the purpose of controlling the operating speed of the load actuator 4.
However, after the multi-pump confluence technology is adopted, the running speed of the system is improved, but the following problems are brought about correspondingly:
1. under the condition of constant engine speed, the power required by the load is not adjustable;
2. under the condition of constant rotating speed, the requirement of special working conditions (such as overhaul, maintenance and the like) on the output power of the engine is far higher than that of other working conditions, and the engine with higher power needs to be selected; the use of a more powerful engine results in increased host costs, fuel consumption and post-maintenance costs.
In view of the above-mentioned shortcomings of the prior art, there is a need for a new hydraulic system that overcomes or alleviates the above-mentioned shortcomings of the prior art.
Disclosure of Invention
The invention aims to solve the technical problem of providing a power control hydraulic system which can adjust the power required by a load and meet the requirements of various working conditions on the output power.
Further, the technical problem to be solved by the invention is to provide a crane, which has a larger selection space in the design and model selection stages.
In order to achieve the above object, a first aspect of the present invention provides a power control hydraulic system, including a first fixed displacement pump, a second fixed displacement pump, an operation valve, a plurality of load actuators, wherein the operation valve is connected to each of the load actuators, the first fixed displacement pump and the second fixed displacement pump are connected to an oil inlet of the operation valve, respectively, so as to supply oil to each of the load actuators through the operation valve, the power control hydraulic system further includes a flow control valve, the flow control valve includes a first oil outlet connected to the oil inlet of the operation valve, a second oil outlet connected to a main oil return path, and a first oil inlet connected to the first fixed displacement pump, and a valve port opening degree of the second oil outlet of the flow control valve is controllable, so as to adjust a flow rate input to each of the load actuators.
Preferably, the flow control valve includes a sequence valve and a main valve with an adjustable valve port opening, the second oil port of the sequence valve and the oil inlet of the main valve are both connected to the first oil inlet of the flow control valve, the first oil port of the sequence valve is connected to the first oil outlet of the flow control valve, and the oil outlet of the main valve is connected to the second oil outlet of the flow control valve.
Further, the main valve is a manual proportional valve or an electro-hydraulic proportional valve.
More preferably, the flow control valve further comprises a pressure reducing valve and a proportional valve, the proportional valve comprises a first oil port connected with the valve rod control cavity of the main valve, a second oil port connected with an oil tank through an oil return port of the flow control valve, and a third oil port connected with an oil outlet of the pressure reducing valve, and an oil inlet of the pressure reducing valve is connected with the second constant delivery pump through a second oil inlet of the flow control valve.
The proportional valve is a proportional electromagnetic valve, and the controller controls the opening degree of a valve port of a first oil port of the proportional valve according to received load information fed back by each flow sensor.
Particularly preferably, the pressure reducing valve is a proportional pressure reducing valve.
Preferably, the flow control valve further comprises a pressure reducing valve and an electromagnetic directional valve, the electromagnetic directional valve comprises a first oil port connected with the valve rod control cavity of the main valve, a second oil port connected with the oil tank through an oil return port of the flow control valve, and a third oil port connected with an oil outlet of the pressure reducing valve, an oil inlet of the pressure reducing valve is connected with the second constant delivery pump through a second oil inlet of the flow control valve, and the pressure reducing valve is a proportional pressure reducing valve.
More preferably, the hydraulic control system further comprises a controller and flow sensors installed on the load execution mechanisms, wherein the controller controls the first oil port of the electromagnetic directional valve to be selectively communicated with the second oil port or the third oil port of the electromagnetic directional valve according to received load information fed back by the flow sensors.
Typically, the first quantitative pump is in forward communication with the first oil inlet of the flow control valve through a first check valve, the second quantitative pump is in forward communication with the second oil inlet of the flow control valve through a second check valve, and the oil inlet of the operating valve is connected to an oil path between the second check valve and the second oil inlet of the flow control valve.
Optionally, the flow control valve further includes a third check valve, the third check valve is located on an oil path between the oil outlet of the main valve and the second oil outlet of the flow control valve, so that the oil path between the oil outlet of the main valve and the second oil inlet of the flow control valve can be conducted in the forward direction, and the oil return port of the main valve is connected to the oil tank through the oil return port of the flow control valve.
Typically, the operating valve comprises a plurality of groups of control valve groups, an operating oil inlet path and an operating oil return path, and the operating oil inlet path is communicated with an oil inlet of the operating valve; the control valve group comprises a multi-way valve and a pressure compensation valve connected with the multi-way valve, and each multi-way valve is arranged between the operation oil inlet oil way and the operation oil return oil way in parallel and is respectively connected with each load execution mechanism in a one-to-one correspondence mode.
The invention provides a crane, which comprises the power control hydraulic system in any one of the technical solutions of the first aspect.
Through the technical scheme, the flow control valve is arranged in a targeted manner, the flow acting on the load executing mechanism can be adjusted through the flow control valve, the output power of the load executing mechanism is optimized, the output power of the load executing mechanism is adjustable, and the power required by the load executing mechanism can be matched with the output power distributed to the corresponding load executing mechanism by the engine.
The flow control valve has multiple control modes such as manual control, hydraulic control and electric control, and can be selected, so that a larger selection space is provided for design.
In addition, for the constant displacement pump confluence hydraulic control system in the prior art, under the condition of constant rotating speed, the requirement of a special working condition on the output power of the engine is far higher than that of other working conditions on the output power of the engine, and the engine with higher power needs to be selected; however, when the power control hydraulic system is applied to a crane, the requirement of a special working condition on power can be met by adjusting the output flow, so that the corresponding equipment can have a larger selection space in the stages of design and model selection.
Additional features and more prominent advantages of the invention will be set forth in the detailed description which follows.
Drawings
FIG. 1 is a hydraulic schematic diagram of a constant displacement pump converging hydraulic system of a crane in the prior art;
FIG. 2 is a hydraulic schematic of a power-controlled hydraulic system according to one embodiment of the present invention;
FIG. 3 is a schematic diagram of one embodiment of a flow control valve of the present invention;
FIG. 4 is a schematic diagram of another embodiment of a flow control valve of the present invention;
fig. 5 is a schematic diagram of another embodiment of a flow control valve of the present invention.
Description of the reference numerals
1 first constant displacement pump 2 second constant displacement pump
3 operating valve P1 operating valve's first oil inlet
The second oil inlet 31 of the P2 operating valve operates the oil inlet path
32-operation oil return path 33 multi-way valve
34 pressure compensating valve 35 overflow valve
36 three-way flow valve 37 one-way overflow valve
4 load actuator 5 flow control valve
First oil outlet of A1 flow control valve and second oil outlet of A2 flow control valve
First oil inlet of A3 flow control valve and second oil inlet of A4 flow control valve
First oil port of a1 sequence valve and second oil port of a2 sequence valve
Oil inlet of main valve b1
Oil outlet of b2 main valve and oil return port of b3 main valve
53 reducing valve 54 proportional valve
First oil port of c1 proportional valve and second oil port of c2 proportional valve
First oil port of d1 electromagnetic directional valve and second oil port of d2 electromagnetic directional valve
6 primary oil return path 71 first check valve
72 second check valve 8 balance valve
Detailed Description
The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.
Furthermore, the terms "first", "second", "third" are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated, and therefore the features defined "first", "second", "third" may explicitly or implicitly include one or more of the features described.
In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "disposed," "mounted," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; either directly or indirectly through intervening media, either internally or in any combination thereof. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
First, it should be noted that, after knowing the technical idea of the hydraulic connection relationship of the present invention, it is also possible for those skilled in the art to simply replace the oil passage or the valve, etc. to achieve the function of the power control hydraulic system of the present invention, and this also belongs to the protection scope of the present invention. The related hydraulic components, such as directional valves, pressure reducing valves, check valves, proportional valves, relief valves, hydraulic cylinders, hydraulic pumps, etc., are well known to those skilled in the art and are common components in existing hydraulic systems, and therefore, these hydraulic components will be described only briefly below, with the description focusing on the inventive hydraulic connection relationship of the power control hydraulic system of the present invention.
Fig. 1 shows a conventional hydraulic system for converging fixed displacement pumps of a crane, in which the flows output by a first fixed displacement pump 1 and a second fixed displacement pump 2 respectively flow together through a first check valve 71 and a second check valve 72 on an operating valve 3, and after the flows flow together through a multi-way valve 33 and a corresponding pressure compensating valve 34, the flows act on a corresponding load actuator 4 through a corresponding balance valve 8, so as to achieve the purpose of controlling the operating speed of the load actuator 4. In a normal working condition, the load pressure required by the load actuator 4 is determined, the flow output by the first fixed displacement pump 1 and the second fixed displacement pump 2 is determined, namely the power required by the load actuator 4 is determined, and therefore the output power of the engine is determined, namely the power required by the load actuator 4 is not adjustable; however, in special working conditions, for example, when special working conditions such as maintenance and repair are performed, the special working conditions such as maintenance and repair are not common working conditions; at this time, the load pressure required by the load executing mechanism 4 is increased, the flow output by the first fixed displacement pump 1 and the flow output by the second fixed displacement pump 2 are kept unchanged, the power required by the load executing mechanism 4 is increased, and in order to meet the requirement, when the model selection is designed, a large-power engine is often required to be selected, so that the cost of the main engine, the oil consumption and the later maintenance cost are increased.
For this purpose, the invention is originally provided with a flow control valve 5, the flow control valve 5 can adjust the flow quantity flowing into the operating valve 3, thereby adjusting the power supplied to the load actuator 4; particularly, for special working conditions, under the condition that the power required by the load executing mechanism 4 is constant, the load pressure of the load executing mechanism 4 can be increased by reducing the flow rate, so that the requirements of special working conditions such as maintenance and the like are met.
A specific embodiment of the power control hydraulic system of the present invention will be described below.
As shown in fig. 2, the power control hydraulic system according to the basic embodiment of the present invention includes a first fixed displacement pump 1, a second fixed displacement pump 2, a pilot valve 3, and a plurality of load actuators 4, the operating valve 3 is respectively connected with each load executing mechanism 4, the first fixed displacement pump 1 and the second fixed displacement pump 2 are respectively connected with an oil inlet of the operating valve 3, so that oil can be supplied to each of the load actuators 4 through the pilot valve 3, and a flow control valve 5, the flow control valve 5 comprises a first oil outlet A1 connected with the oil inlet of the operating valve 3, a second oil outlet A2 connected with a main oil return path 6 and a first oil inlet A3 connected with the first quantitative pump 1, the valve port opening degree of the second oil outlet a2 of the flow control valve 5 can be controlled to adjust the flow rate input to each load actuator 4.
In the basic embodiment, by controlling the flow control valve 5, a part of the flow output by the first fixed displacement pump 1 can flow back to the oil tank via the first oil inlet A3 and the second oil outlet a2 of the flow control valve 5, and the valve opening degree of the second oil outlet a2 of the flow control valve 5 can be adjusted, so that the magnitude of the part of the flow can be controlled to adjust the flow of the hydraulic oil flowing into the pilot valve 3 through the first oil outlet a1 of the flow control valve 5, thereby adjusting the magnitude of the output power to each load actuator 4; moreover, for special working conditions, the output power of the load executing mechanism 4 can be kept definite, the load pressure of the load executing mechanism 4 can be adjusted by adjusting the flow input to the corresponding load executing mechanism 4, and the requirement of the special working conditions can be well met without selecting an engine with higher power during model selection. Wherein, the load executing mechanism 4 can be a hydraulic oil cylinder.
The operating valve 3 comprises a plurality of groups of control valve groups, an operating oil inlet path 31 and an operating oil return path 32, the operating oil inlet path 31 is communicated with the oil inlets of the operating valve 3, and there may be one or more oil inlets, for example, there are two oil inlets, which are divided into a first oil inlet P1 and a second oil inlet P2 of the operating valve 3, and are respectively connected with the first fixed displacement pump 1 and the second fixed displacement pump 2; the control valve group comprises a multi-way valve 33 and a pressure compensation valve 34 connected with the multi-way valve 33, each multi-way valve 33 is arranged between an operation oil inlet path 31 and an operation oil return path 32 in parallel and is respectively connected with each load executing mechanism 4 in a one-to-one correspondence manner, a three-way flow valve 36 and an overflow valve 35 are also arranged between the operation oil inlet path 31 and the operation oil return path 32, and in a conventional crane constant displacement pump confluence hydraulic system, the flow exceeding the requirement of each load executing mechanism 4 flows back to an oil tank through the three-way flow valve 36, so that power loss of a certain degree is caused; however, in the power control hydraulic system of the present invention, the flow rate flowing into the pilot valve 3 can be controlled by the flow control valve 5, i.e. the flow rate can just meet the requirements of each load actuator 4, and the flow loss through the three-way flow valve 36 is reduced or even avoided; the overflow valve 35 can limit the highest pressure of the system and protect the safety of the system; a one-way overflow valve 37 is arranged between each load executing mechanism 4 and the control oil return oil way 32, and the one-way overflow valve 37 is also connected with the corresponding multi-way valve 33 so as to supplement oil for each load executing mechanism 4 and prevent air suction; further, each multi-way valve 33 acts on the corresponding load actuator 4 through the corresponding balance valve 8 to control the corresponding load actuator 4 to operate stably.
In a specific embodiment, referring to fig. 3, the flow control valve 5 includes a sequence valve 51 and a main valve 52, a valve port opening degree of the main valve 52 is adjustable, a second port a2 of the sequence valve 51 is connected to a first oil inlet A3 of the flow control valve 5, an oil inlet b1 of the main valve 52 is also connected to a first oil inlet A3 of the flow control valve 5, a first port a1 of the sequence valve 51 is connected to a first oil outlet a1 of the flow control valve 5, an oil outlet b2 of the main valve 52 is connected to a second oil outlet a2 of the flow control valve 5, and the valve port opening degree of a second oil outlet a2 of the flow control valve 5 can be controlled by adjusting the valve port opening degree of the oil outlet b2 of the main.
The main valve 52 may be a manual proportional valve or an electro-hydraulic proportional valve to control the flow rate through the main valve, so that the flow rate flowing into the pilot valve 3 through the sequence valve 51 can be controlled.
In a preferred embodiment, referring to fig. 4, the flow control valve 5 may further include a pressure reducing valve 53 and a proportional valve 54, the proportional valve 54 includes a first port c1, a second port c2 and a third port c3, the first port c1 of the proportional valve 54 is connected to the valve rod control chamber of the main valve 52, the second port c2 of the proportional valve 54 is connected to the oil tank through an oil return port a5 of the flow control valve 5, the third port c3 of the proportional valve 54 is connected to an oil outlet of the pressure reducing valve 53, and an oil inlet of the pressure reducing valve 53 is connected to the second fixed displacement pump 2 through a second oil inlet a4 of the flow control valve 5; the proportional valve 54 can control the spool flow area of the main valve 52, and specifically, when the special operating mode is performed, a part of the flow output by the second fixed displacement pump 2 flows through the pressure reducing valve 53, the third port c3 of the proportional valve 54 and the first port c1 of the proportional valve 54 into the stem control chamber of the main valve 52, and pushes the spool of the main valve 52 to move, so that the spool flow area of the main valve 52, that is, the flow input to the pilot valve 3, can be controlled because the proportional valve 54 can control the flow. The pressure reducing valve 53 may be a proportional pressure reducing valve.
Further, the proportional valve 54 may be a proportional solenoid valve, which controls the output flow rate according to the magnitude of the coil current, and each load actuator 4 may be provided with a flow sensor, and the controller may control the valve opening of the first oil port c1 of the proportional valve 54 according to the received load information fed back by each flow sensor, so as to control the valve core flow area of the main valve 52, and control the flow rate of the input pilot valve 3 in an electric control manner; for example, the controller may be a programmable logic controller, and the valve port opening degree of the first port c1 of the proportional valve 54 is controlled by an existing control program.
In another preferred embodiment, referring to fig. 5, the flow control valve 5 may further include a pressure reducing valve 53 and a solenoid directional valve 55, the solenoid directional valve 55 includes a first port d1, a second port d2 and a third port d3, the first port d1 of the solenoid directional valve 55 is connected to the valve rod control cavity of the main valve 52, the second port d2 of the solenoid directional valve 55 is connected to the oil tank through an oil return port a5 of the flow control valve 5, the third port d3 of the solenoid directional valve 55 is connected to an oil outlet of the pressure reducing valve 53, an oil inlet of the pressure reducing valve 53 is connected to the second fixed displacement pump 2 through a second oil inlet a4 of the flow control valve 5, and the pressure reducing valve 53 is a proportional pressure reducing valve; when the special operating mode is performed, a part of the flow output by the second fixed displacement pump 2 flows through the pressure reducing valve 53, the third port d3 of the electromagnetic directional valve 55, and the first port d1 of the electromagnetic directional valve 55 into the valve stem control chamber of the main valve 52, and pushes the valve core of the main valve 52 to move, and since the pressure reducing valve 53 can control the flow, the valve core flow area of the main valve 52 can be controlled, that is, the flow input to the pilot valve 3 can be controlled in a pilot-controlled manner.
Similarly, each load actuator 4 may be provided with a flow sensor, and the controller may control the on/off of the third port d3 of the electromagnetic directional valve 55 and the first port d1 thereof according to the received load information fed back by each flow sensor, adjust the proportional pressure reducing valve, control the valve core flow area of the main valve 52, and control the flow rate of the input pilot valve 3 in a pilot-controlled manner; for example, the controller may be a programmable logic controller, and the opening and closing of the third port d3 and the first port d1 of the electromagnetic directional valve 55 are controlled by an existing control program.
As a specific example, in order to ensure the safety of the system, a first check valve 71 may be disposed between the first fixed displacement pump 1 and the first oil inlet A3 of the flow control valve 5, so that the first fixed displacement pump 1 is in forward communication with the first oil inlet A3 of the flow control valve 5, a second check valve 72 may be disposed between the second fixed displacement pump 2 and the second oil inlet a4 of the flow control valve 5, so that the second fixed displacement pump 2 is in forward communication with the second oil inlet a4 of the flow control valve 5, so as to prevent the hydraulic oil from flowing in the reverse direction, which may damage the first fixed displacement pump 1 and the second fixed displacement pump 2, furthermore, the oil inlet of the pilot valve 3 is connected to the oil path between the second check valve 72 and the second oil inlet a4 of the flow control valve 5, and the second fixed displacement pump 2 can supply both pilot control oil to the flow control valve 5 and hydraulic oil for work to the pilot valve 3.
As shown in fig. 3 to 5, the flow control valve 5 further includes a third check valve 56, the third check valve 56 is located on the oil path between the oil outlet b2 of the main valve 52 and the second oil outlet a4 of the flow control valve 5 so as to enable the oil outlet b2 of the main valve 52 to be in forward communication with the second oil inlet a4 of the flow control valve 5, and the oil return port b3 of the main valve 52 is connected to the oil tank through the oil return port a5 of the flow control valve 5, and when it is not necessary to adjust the flow rate inputted to the pilot valve 3, the oil outlet b2 of the main valve 52 is controlled to be in communication with the oil return port b3 thereof, so that the entire flow rate flowing through the flow control valve 5 flows to the pilot valve 3 through the sequence.
Referring to fig. 2 to 5, the power control hydraulic system according to the preferred embodiment of the present invention includes a first fixed displacement pump 1, a second fixed displacement pump 2, an operation valve 3, a plurality of load actuators 4 and a flow control valve 5, wherein the operation valve 3 is connected to the corresponding load actuators 4 through corresponding balance valves 8, the first fixed displacement pump 1 and the second fixed displacement pump 2 are connected to first oil inlets A3 and second oil inlets a4 of the flow control valve 5 through first check valves 71 and second check valves 72, respectively, one to one correspondence, a first oil inlet P1 of the operation valve 3 is connected to a first oil outlet a1 of the flow control valve 5, a second oil inlet P2 of the operation valve 3 is connected to an oil path between the second check valves 72 and a second oil inlet a4 of the flow control valve 5, a second oil outlet a2 of the flow control valve 5 is connected to a main oil return path 6, and the operation oil path 31 connects the first oil inlet P1 and a second oil inlet P2 of the operation valve 3, an operation oil return path 32 of the operation valve 3 is connected with the main oil return path 6, a multi-way valve 33 of the operation valve 3 is connected with a pressure compensation valve 34, each multi-way valve 33 is arranged between the operation oil inlet path 31 and the operation oil return path 32 in parallel and is respectively connected with each load executing mechanism 4 in a one-to-one correspondence manner, and an overflow valve 35 and a three-way flow valve 36 are further connected between the operation oil inlet path 31 and the operation oil return path 32;
wherein, the flow control valve 5 may include a sequence valve 51 and a main valve 52, the main valve 52 is a manual proportional valve or an electro-hydraulic proportional valve, the oil inlet b1 of the main valve 52 is also connected to the first oil inlet A3 of the flow control valve 5, the oil outlet b2 of the main valve 52 is connected to the second oil outlet a2 of the flow control valve 5, the oil return b3 of the main valve 52 is connected to the oil tank through the oil return a5 of the flow control valve 5, the second oil outlet a2 of the sequence valve 51 is connected to the first oil inlet A3 of the flow control valve 5, the first oil outlet a1 of the sequence valve 51 is connected to the first oil outlet a1 of the flow control valve 5, so as to directly control the opening degree of the valve port of the main valve 52, the flow of the first constant volume pump 1 flowing through the flow control valve 5 is divided into two parts, one part of the flow flows into the pilot valve 3 through the sequence valve 51, and the other part of the flow flows, the requirement of the system on the output power of the engine is adjusted by changing the flow, the requirement on the output power of the engine is reduced on the premise of realizing corresponding functions, and the technical problem that the engine with higher power needs to be selected due to special working conditions in the model selection process of the engine is solved; in addition, the flow control valve 5 can also be in an electric control mode and a hydraulic control mode; specifically, when the flow control valve 5 is in the electrical control mode, the flow control valve 5 may include a sequence valve 51, a main valve 52, the oil inlet b1 of the main valve 52 is also connected with the first oil inlet A3 of the flow control valve 5, the oil outlet b2 of the main valve 52 is connected with the second oil outlet a2 of the flow control valve 5, the oil return port b3 of the main valve 52 is connected with the oil tank through the oil return port a5 of the flow control valve 5, the second oil port a2 of the sequence valve 51 is connected with the first oil inlet A3 of the flow control valve 5, the first oil port a1 of the sequence valve 51 is connected with the first oil outlet a1 of the flow control valve 5, the first oil port c1 of the proportional valve 54 is connected with the valve rod control cavity of the main valve 52, the second oil port c2 of the proportional valve 54 is connected with the oil tank through the oil return port a5 of the flow control valve 5, the third oil port c3 of the proportional valve 54 is connected with the oil outlet of the pressure reducing valve 53, and the oil inlet of the pressure reducing valve 53 is connected with the second fixed displacement; thus, the flow area of the valve core of the main valve 52 is adjusted through the action of the proportional valve 54 on the valve core of the main valve 52, the flow rate flowing back to the oil tank through the main valve 52 can be controlled, the technical problem that the engine with higher power needs to be selected due to special working conditions in the model selection process of the engine is solved, in addition, the load pressure of the load execution mechanism 4 can be adjusted, and the requirement of the load execution mechanism 4 on the load pressure under the special working conditions is met; further, the proportional valve 54 is a proportional solenoid valve, a flow sensor is installed on each load actuator 4, and the opening degree of the valve port of the first oil port c1 of the proportional valve 54 is controlled by using a controller according to received load information fed back by each flow sensor, so that the valve core flow area of the main valve 52 is controlled, the purpose of controlling the flow acting on the load actuator 4 is achieved, and the power required by the load actuator 4 can be matched with the engine in real time; when the flow control valve 5 is in the pilot-operated mode, the proportional valve 54 in the pilot-operated mode may be replaced with the electromagnetic directional valve 55, the pressure reducing valve 53 may be a proportional pressure reducing valve, the valve core flow area of the main valve 52 may be controlled by the pressure reducing valve 53, and similarly, the controller may control the opening and closing of the third port d3 and the first port d1 of the electromagnetic directional valve 55 according to the received load information fed back by the flow sensors, so as to control the flow rate acting on the load actuator 4.
That is, the flow control valve 5 can perform on-off control on the output flow of the first fixed displacement pump 1, thereby controlling the flow input into the control valve 3, satisfying the flow demand of each load actuator 4, and enabling the power required by the load actuator 4 to match the engine; moreover, the technical problem that the requirement of a special working condition on the output power of the engine is far higher than that of other working conditions on the output power of the engine, so that the engine with higher power needs to be selected can be solved, and the cost of a main engine, the oil consumption and the later maintenance cost can be reduced to a certain extent.
The crane provided by the invention comprises the power control hydraulic system in any one of the technical schemes, so that the crane at least has all the beneficial effects brought by the technical scheme of the embodiment of the power control hydraulic system.
In a known manner, a high-altitude area can cause the reduction of the power of an engine, and in a design stage, if the influence of the high-altitude area on the power of the engine is considered, the excessive selection safety margin can be caused, and unnecessary waste is caused; after the power control hydraulic system is applied to the crane, the crane can control the flow transmitted to the load execution mechanism 4 through the flow control valve 5, the requirement on the power required by the load execution mechanism 4 is met, and the influence caused by the reduction of the power of an engine in a high-altitude area is avoided.
The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, numerous simple modifications can be made to the technical solution of the invention, including combinations of the individual specific technical features in any suitable way. The invention is not described in detail in order to avoid unnecessary repetition. Such simple modifications and combinations should be considered within the scope of the present disclosure as well.
Claims (12)
1. A power control hydraulic system comprises a first fixed displacement pump (1), a second fixed displacement pump (2), an operating valve (3) and a plurality of load execution mechanisms (4), wherein the operating valve (3) is respectively connected with each load execution mechanism (4), the first fixed displacement pump (1) and the second fixed displacement pump (2) are respectively connected with an oil inlet of the operating valve (3) so as to supply oil to each load execution mechanism (4) through the operating valve (3), the power control hydraulic system is characterized by further comprising a flow control valve (5), the flow control valve (5) comprises a first oil outlet (A1) connected with the oil inlet of the operating valve (3), a second oil outlet (A2) connected with a main oil return path (6) and a first oil inlet (A3) connected with the first fixed displacement pump (1), and the opening degree of the second oil outlet (A2) of the flow control valve (5) can be controlled, so as to be able to regulate the flow rate fed to each of the load actuators (4).
2. The power control hydraulic system according to claim 1, characterized in that the flow control valve (5) comprises a sequence valve (51) and a main valve (52) with an adjustable valve port opening degree, the second oil port (a2) of the sequence valve (51) and the oil inlet (b1) of the main valve (52) are both connected with the first oil inlet (A3) of the flow control valve (5), the first oil port (a1) of the sequence valve (51) is connected with the first oil outlet (A1) of the flow control valve (5), and the oil outlet (b2) of the main valve (52) is connected with the second oil outlet (A2) of the flow control valve (5).
3. A power controlled hydraulic system according to claim 2, characterized in that the main valve (52) is a manual proportional valve or an electro-hydraulic proportional valve.
4. The power control hydraulic system according to claim 2, characterized in that the flow control valve (5) further comprises a pressure reducing valve (53) and a proportional valve (54), the proportional valve (54) comprises a first oil port (c1) connected with the valve stem control chamber of the main valve (52), a second oil port (c2) connected with an oil tank through an oil return port (a5) of the flow control valve (5), and a third oil port (c3) connected with an oil outlet of the pressure reducing valve (53), and an oil inlet of the pressure reducing valve (53) is connected with the second fixed displacement pump (2) through a second oil inlet (a4) of the flow control valve (5).
5. The power control hydraulic system as claimed in claim 4, further comprising a controller and flow sensors mounted on each load actuator (4), wherein the proportional valve (54) is a proportional solenoid valve, and the controller controls the opening degree of the first oil port (c1) of the proportional valve (54) according to the received load information fed back by each flow sensor.
6. A power controlled hydraulic system according to claim 4, characterized in that the pressure reducing valve (53) is a proportional pressure reducing valve.
7. The power control hydraulic system according to claim 2, characterized in that the flow control valve (5) further comprises a pressure reducing valve (53) and a solenoid directional valve (55), the solenoid directional valve (55) comprises a first oil port (d1) connected with the valve rod control chamber of the main valve (52), a second oil port (d2) connected with an oil tank through an oil return port (A5) of the flow control valve (5), and a third oil port (d3) connected with an oil outlet of the pressure reducing valve (53), an oil inlet of the pressure reducing valve (53) is connected with the second fixed displacement pump (2) through a second oil inlet (A4) of the flow control valve (5), and the pressure reducing valve (53) is a proportional pressure reducing valve.
8. The power control hydraulic system as claimed in claim 7, further comprising a controller and flow sensors mounted on each load actuator (4), wherein the controller controls the first oil port (d1) of the electromagnetic directional valve (55) to selectively communicate with the second oil port (d2) or the third oil port (d3) according to received load information fed back by each flow sensor.
9. The power-controlled hydraulic system as claimed in claim 7, characterized in that the first fixed displacement pump (1) is in forward communication with a first oil inlet (A3) of the flow control valve (5) via a first non-return valve (71), the second fixed displacement pump (2) is in forward communication with a second oil inlet (A4) of the flow control valve (5) via a second non-return valve (72), and the oil inlet of the pilot valve (3) is connected to the oil circuit between the second non-return valve (72) and the second oil inlet (A4) of the flow control valve (5).
10. A power control hydraulic system according to any one of claims 2 to 9, characterized in that the flow control valve (5) further comprises a third one-way valve (56), said third one-way valve (56) being located in the oil path between the outlet (b2) of the main valve (52) and the second outlet (a4) of the flow control valve (5) to enable a forward communication of the oil path between the outlet (b2) of the main valve (52) and the second inlet (a4) of the flow control valve (5), and the return (b3) of the main valve (52) being connected to the oil tank through the return (a5) of the flow control valve (5).
11. The power control hydraulic system according to any one of claims 1 to 9, characterized in that the pilot valve (3) comprises multiple sets of control valve groups, a pilot oil inlet passage (31) and a pilot oil return passage (32), wherein the pilot oil inlet passage (31) is communicated with an oil inlet of the pilot valve (3); the control valve group comprises a multi-way valve (33) and pressure compensation valves (34) connected with the multi-way valve (33), and the multi-way valves (33) are arranged between the operation oil inlet oil path (31) and the operation oil return oil path (32) in parallel and are respectively connected with the load executing mechanisms (4) in a one-to-one correspondence mode.
12. A crane, characterized by comprising a power-controlled hydraulic system according to any one of claims 1 to 11.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911338964.6A CN110953197B (en) | 2019-12-23 | 2019-12-23 | Power control hydraulic system and crane |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911338964.6A CN110953197B (en) | 2019-12-23 | 2019-12-23 | Power control hydraulic system and crane |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110953197A true CN110953197A (en) | 2020-04-03 |
| CN110953197B CN110953197B (en) | 2021-03-19 |
Family
ID=69983476
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911338964.6A Active CN110953197B (en) | 2019-12-23 | 2019-12-23 | Power control hydraulic system and crane |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110953197B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111425470A (en) * | 2020-04-14 | 2020-07-17 | 广西玉柴重工有限公司 | Dual-mode flow control device of hydraulic system |
| CN111677700A (en) * | 2020-05-19 | 2020-09-18 | 江苏理工学院 | Turnover elevator hydraulic system based on load port independent control |
| CN114294303A (en) * | 2022-01-05 | 2022-04-08 | 三一汽车起重机械有限公司 | Power-adjustable hydraulic system, power-adjustable hydraulic method and working machine |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS578382A (en) * | 1980-06-20 | 1982-01-16 | Toyo Kikai Kinzoku Kk | Flow control of pressure fluid |
| CN201246355Y (en) * | 2008-05-24 | 2009-05-27 | 邱景发 | Hydraulic speed variator of crane |
| CN101858091A (en) * | 2010-04-22 | 2010-10-13 | 北京矿冶研究总院 | Quantitative pump hydraulic control system of working mechanism of underground scraper |
| CN206144874U (en) * | 2016-10-31 | 2017-05-03 | 徐工集团工程机械股份有限公司科技分公司 | Two constant delivery pumps intelligence confluence system |
| CN107725504A (en) * | 2017-09-21 | 2018-02-23 | 林德（中国）叉车有限公司 | A kind of hydraulic system and hydraulic control method that suitable performance is provided for load |
| CN108825571A (en) * | 2018-09-04 | 2018-11-16 | 阜新北鑫星液压有限公司 | A kind of load-sensitive gear pump with variable capacity system |
| CN109854558A (en) * | 2019-03-29 | 2019-06-07 | 徐工集团工程机械股份有限公司科技分公司 | Hydraulic system and engineering truck |
| CN110294417A (en) * | 2019-07-18 | 2019-10-01 | 徐州徐工随车起重机有限公司 | A kind of interflow switching valve, speed regulation interlock control and from walking crane |
-
2019
- 2019-12-23 CN CN201911338964.6A patent/CN110953197B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS578382A (en) * | 1980-06-20 | 1982-01-16 | Toyo Kikai Kinzoku Kk | Flow control of pressure fluid |
| CN201246355Y (en) * | 2008-05-24 | 2009-05-27 | 邱景发 | Hydraulic speed variator of crane |
| CN101858091A (en) * | 2010-04-22 | 2010-10-13 | 北京矿冶研究总院 | Quantitative pump hydraulic control system of working mechanism of underground scraper |
| CN206144874U (en) * | 2016-10-31 | 2017-05-03 | 徐工集团工程机械股份有限公司科技分公司 | Two constant delivery pumps intelligence confluence system |
| CN107725504A (en) * | 2017-09-21 | 2018-02-23 | 林德（中国）叉车有限公司 | A kind of hydraulic system and hydraulic control method that suitable performance is provided for load |
| CN108825571A (en) * | 2018-09-04 | 2018-11-16 | 阜新北鑫星液压有限公司 | A kind of load-sensitive gear pump with variable capacity system |
| CN109854558A (en) * | 2019-03-29 | 2019-06-07 | 徐工集团工程机械股份有限公司科技分公司 | Hydraulic system and engineering truck |
| CN110294417A (en) * | 2019-07-18 | 2019-10-01 | 徐州徐工随车起重机有限公司 | A kind of interflow switching valve, speed regulation interlock control and from walking crane |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111425470A (en) * | 2020-04-14 | 2020-07-17 | 广西玉柴重工有限公司 | Dual-mode flow control device of hydraulic system |
| CN111677700A (en) * | 2020-05-19 | 2020-09-18 | 江苏理工学院 | Turnover elevator hydraulic system based on load port independent control |
| CN111677700B (en) * | 2020-05-19 | 2022-04-08 | 江苏理工学院 | Turnover elevator hydraulic system based on load port independent control |
| CN114294303A (en) * | 2022-01-05 | 2022-04-08 | 三一汽车起重机械有限公司 | Power-adjustable hydraulic system, power-adjustable hydraulic method and working machine |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110953197B (en) | 2021-03-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106759621B (en) | Load-sensitive formula loading machine determines variable delivery hydraulic system | |
| CN110953197B (en) | Power control hydraulic system and crane | |
| CN207762060U (en) | A kind of overhead working truck system | |
| CN104884818A (en) | Proportional flow control of a fluid pump assembly | |
| CN104032792A (en) | Quantitative and variable hydraulic system of loading machine | |
| CN104163385A (en) | Hydraulic control system for winch | |
| CN112746996B (en) | Load sensitive system and engineering hoisting machinery | |
| CN102587443A (en) | Multiway valve hydraulic control system of crawler excavator | |
| CN201068843Y (en) | Electrohydraulic load pressure flow control variable plunger pump | |
| CN104863914A (en) | Electrohydraulic joint control flow collecting valve | |
| CN108302073A (en) | A kind of automobile-used impeller rotating hydraulic system of sand throwing fire extinguishing | |
| CN108443273B (en) | A kind of emergency management and rescue vehicle equipment oil return line pressure compensation throttle control system | |
| JP2022516145A (en) | Variable capacity hydraulic pump set and excavator | |
| WO2023274210A1 (en) | Hydraulic system capable of multi-stage pressure control and pressure speed regulation, and working machine | |
| CN109505812B (en) | Variable pump dual-mode control hydraulic system and tunnel operation vehicle | |
| CN208089650U (en) | A kind of automobile-used impeller rotating hydraulic system of sand throwing fire extinguishing | |
| CN201050076Y (en) | Lead operation valve oil supplying system | |
| CN103727078B (en) | Crane and hydraulic system thereof | |
| CN217462693U (en) | Hydraulic system with multiple pressure outputs and engineering machinery comprising same | |
| CN107725504B (en) | Hydraulic system capable of providing proper performance for load and hydraulic control method | |
| CN204716650U (en) | Variable priority flow leveling integrated valve group | |
| CN213392919U (en) | Double-loop hydraulic system with rear confluence of main throttling port | |
| CN201747689U (en) | Pressure regulating device of hydraulic system | |
| CN216241552U (en) | Pumping hydraulic system and wet spraying machine | |
| CN112879391A (en) | Oil supplementing device and closed system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |