JP4229131B2 - Locking device and work machine equipped with the same - Google Patents

Description

  The present invention relates to a work machine such as a hydraulic excavator configured to be able to switch a preset brake mode.

  Conventionally, a work machine has a self-propelled airframe and an attachment that can be raised and lowered on the airframe, and can perform various types of work (excavation work if a hydraulic excavator) by raising and lowering the attachment. It is said that.

  This type of work machine includes a parking brake that mechanically prevents the rotation of the axle of the airframe using a friction member and the like, and a work brake that prevents the rotation of the axle using the power of the work machine. ing.

  The work machine is known to have a brake mode that can be selected by the operator according to the situation when working with the attachment, parking the aircraft, or running the aircraft. (For example, Patent Document 1).

  The wheeled excavator of Patent Document 1 includes a brake operation changeover switch that can be switched between a W position selected during work, a P position selected during parking, and a D position selected during traveling. The operation of the brake is switched according to the position selected by the brake switch.

Specifically, the parking brake and the service (work) brake are operated at the W position, only the parking brake is operated at the P position, and the parking brake and the service brake are released at the D position.
JP-A-2-272117

  However, since the wheel-type excavator of Patent Document 1 is allowed to transmit the driving force for traveling to the axle even while the brake is operating, the parking brake is worn by driving the axle during such braking operation. This could cause damage and shorten the life of the parking brake.

  In particular, in the state where the P position is selected, since the rotation of the axle is blocked only by the parking brake, the movement of the axle is significantly greater than when both the parking brake and the work brake are operating, When the operator erroneously performs a traveling operation (for example, an accelerator stepping operation) at the P position, the load on the parking brake that tries to keep the wheel unrotatable becomes larger.

  In addition, in the wheel type excavator of Patent Document 1, it is originally necessary to switch to the W position where both the parking brake and the work brake are operated to ensure that the vehicle body is stationary, but to operate the attachment. When the attachment is operated with the position selected, that is, when the work brake is released and only the parking brake is operated, the attachment is used and the reaction force of the work The braking force of the parking brake alone is not enough to counteract, and the vehicle body may move. In this case as well, the parking brake may be damaged due to the movement of the vehicle body.

  This invention is made | formed in view of the said subject, and it aims at providing the working machine provided with the locking device which can make the utility of a parking brake last long, and this.

In order to solve the above-described problems, the present invention provides an airframe that travels according to the rotation of an axle, a work brake that operates to receive a predetermined power supply and keep the axle in a stopped state, and the work brake. A power source that supplies power; and a parking brake that operates to maintain a stop state of the axle using frictional resistance without receiving power from the power source, and the parking brake and the work brake A locking device that locks the rotation of the axle, provided in a work machine that is provided with a plurality of brake modes as an operating state of the vehicle, and a travel drive unit that supplies power to the axle, and the travel drive unit A traveling input unit capable of inputting an instruction for causing the vehicle to travel, and the traveling drive so that power supply to the axle is disabled regardless of the input operation of the traveling input unit. A locking portion for locking the parts, a relief driver for supplying power for relief allows the loaded attachment relief with respect to the machine body is provided on the working machine, for raising and lowering the attachment to the relief driver An undulation input unit capable of inputting and operating instructions, and the lock unit operates as the brake mode when the parking mode for operating the parking brake and releasing the operation of the work brake is selected. On the other hand, when the travel mode for releasing the operation of the parking brake and the work brake is selected as the brake mode, the travel drive unit is unlocked , and the lock unit is set as the brake mode. Regardless of the input operation of the undulation input unit when the parking mode is selected, the attachment The undulation drive unit is locked so that power supply is disabled, and power supply to the attachment is allowed when a work mode for operating the parking brake and work brake is selected as the brake mode. Further, there is provided a lock device for a work machine , wherein the lock of the undulating drive part is released .

  According to the present invention, since the lock portion is provided, power cannot be supplied to the axle even when the operator erroneously inputs the travel input portion when the parking mode is selected as the brake mode. It is possible to suppress an excessive load on the parking brake by locking the traveling drive unit so as to be in the state.

  Therefore, according to the present invention, the utility of the parking brake can be prolonged.

  In the present invention, when the travel mode is selected as the brake mode, the power supply to the axle is allowed, so that the vehicle can travel in the travel mode.

Furthermore, in the present invention, since the power supply from the undulation drive unit to the attachment can be prevented by the lock unit, the operator erroneously inputs the undulation input unit while the parking mode is selected as the brake mode. Even if it is a case, the operation | work by an attachment is prohibited, the situation where the body moves by receiving the reaction force of the said operation | work can be suppressed, and it can suppress that an excessive load arises on a parking brake.

Further , it is preferable that when the work mode is selected as the brake mode, the travel drive unit is locked by the lock unit.

  In this way, even if the operator accidentally operates the travel input unit while the work mode is selected and the work is being performed, it is possible to prevent the working aircraft from traveling. Since it is possible, safety can be further improved.

  In the locking device, the travel input unit is configured to output an instruction for causing the vehicle to travel as an electric signal to the travel drive unit, and the lock unit is configured to travel from the travel input unit to the travel drive unit. It is preferable to lock the traveling drive unit by preventing transmission of an electrical signal.

  According to this configuration, the travel drive unit can be locked so that power supply to the axle is disabled by preventing transmission of an electrical signal output from the travel input unit to the travel drive unit.

  Specifically, the brake unit further includes mode switching means capable of selecting the brake mode and outputting a mode selection signal corresponding to the mode when a specific mode is selected, and the lock unit includes the mode A configuration comprising transmission state switching means for switching a transmission state between a state in which transmission of the electric signal is blocked and a state in which transmission of the electric signal is permitted based on the presence or absence of a mode selection signal output from the switching means; can do.

  According to this configuration, since the operation for switching between the state for preventing the transmission of the electric signal and the state for allowing the electric signal can be performed based on the presence or absence of the mode selection signal, the operation is performed without requiring special control. be able to.

The present invention also provides the locking device, a vehicle body that travels in response to rotation of the axle, a work brake that operates to receive a predetermined power supply and keep the axle in a stopped state, and power to the work brake. A power source for supplying the vehicle, a parking brake that operates to keep the axle stopped using frictional resistance without receiving power from the power source, and operating states of the parking brake and the work brake and a preset braking mode selectable mode selecting means, to the brake mode, the parking mode to cancel the operation of the working brake while operating the parking brake, releasing the actuation of the parking brake and the work brake travel mode, and the work machine work mode for actuating the parking brake and the work brake is equal to or is included Subjected to.

  Furthermore, the present invention provides a machine body that travels according to the rotation of the axle, an attachment that is mounted so as to be able to be raised and lowered, and an operation that operates to keep the axle in a stopped state by receiving a predetermined power supply. A brake, a power source that supplies power to the work brake, and a parking brake that operates to keep the axle in a stopped state using frictional resistance without receiving power from the power source, A locking device that is provided in a work machine having a plurality of brake modes prepared as operating states of the parking brake and the work brake and locks the undulation of the attachment, and a undulation drive unit that supplies undulation power to the attachment; The undulation input unit capable of inputting an instruction to undulate the attachment to the undulation drive unit, and the input operation of the undulation input unit. And a lock portion that locks the hoisting drive portion so that power supply to the attachment is disabled, and the lock portion operates the parking brake and the work brake as the brake mode. When the parking mode for canceling the operation is selected, the hoisting drive unit is locked, while when the work mode for operating the parking brake and the work brake is selected as the brake mode, the hoisting drive unit There is provided a lock device for a work machine characterized by releasing the lock.

  According to the present invention, since the undulation drive unit can be locked so that the power supply to the attachment is disabled by the lock unit, the operator erroneously inputs the undulation while the parking mode is selected as the brake mode. Even when an input operation is performed on a part, it is possible to suppress the situation in which the aircraft moves due to the reaction force of the work by preventing the work by the attachment, and an excessive load is generated on the parking brake. Can be suppressed.

  Therefore, according to the present invention, the utility of the parking brake can be prolonged.

  In the present invention, since the supply of power to the attachment is allowed when the work mode is selected as the brake mode, the work by the attachment is possible in the work mode.

  In the locking device, the undulation drive unit includes a hydraulic pump and an actuator that receives the supply of hydraulic oil from the hydraulic pump to cause the attachment to undulate, and the undulation input unit is supplied from the hydraulic pump to the actuator. The lock unit is configured to be capable of adjusting the hydraulic pressure, and the undulating drive unit is configured so that the hydraulic oil cannot be supplied from the hydraulic pump to the actuator regardless of the operation of the undulation input unit. It is preferable to lock.

  According to this configuration, the undulation operation of the attachment when the parking mode is selected can be prohibited by preventing the hydraulic oil from being supplied from the hydraulic pump to the actuator regardless of the operation of the undulation input unit.

  Specifically, the undulation drive unit includes an electromagnetic valve capable of switching between a supply position that allows supply of hydraulic oil from the hydraulic pump to the actuator and a stop position that stops supply of hydraulic oil to the actuator. The lock unit may be configured to adjust the power supplied to the solenoid valve so that the solenoid valve is in a stop position in response to the parking mode being selected.

  In this way, it is possible to adjust the supply of hydraulic oil from the hydraulic pump to the actuator by operating the electromagnetic valve between the supply position and the stop position.

  Further, when the brake mode can be selected and a specific mode is selected, the brake unit further includes mode selection means capable of outputting a mode selection signal corresponding to the mode, and the lock unit includes the mode selection means A supply state in which the state of power supply to the solenoid valve is switched between a state in which the solenoid valve is operated to a supply position and a state in which the solenoid valve is operated to a stop position based on the presence or absence of a mode selection signal output from It is particularly preferable that switching means is provided.

  According to this configuration, since the operation of switching the electromagnetic valve between the supply position and the stop position can be performed based on the presence or absence of the mode selection signal, the operation can be performed without requiring special control.

  Furthermore, the present invention keeps the axle in a stopped state by receiving a predetermined power from the lock device, an airframe that travels according to the rotation of the axle, an attachment that is mounted on the airframe in a undulating manner. A work brake that operates as described above, a power source that supplies power to the work brake, and a parking brake that operates to keep the axle in a stopped state using frictional resistance without receiving power from the power source, And a mode selection means capable of selecting a preset brake mode as an operating state of the parking brake and the work brake, and the brake mode includes a parking mode for operating the parking brake and releasing the operation of the work brake. And a work machine including at least a work mode for operating a parking brake and a work brake. That.

  According to the present invention, the utility of the parking brake can be prolonged.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a side view showing a wheeled excavator according to an embodiment of the present invention.

  Referring to FIG. 1, a wheeled excavator 1 as an example of a work machine includes a lower traveling body (airframe) 2 having an axle 2b of a tire 2a, and an upper revolving body mounted on the lower traveling body 2 so as to be capable of turning. (Airframe) 3, an attachment 4 supported by the upper swing body 3 so as to be able to undulate, a work brake (not shown) for keeping the axle 2b in a stopped state by using air pressure, An air source for supplying air (power source: not shown), a parking brake (not shown) for keeping the axle 2b stopped using frictional resistance, and a drive for driving the axle 2b and the attachment 4 The apparatus 5 (refer FIG. 2) is provided.

  The attachment 4 includes a boom 6 and an arm 7 connected to the distal end portion of the boom 6. A bucket 8 is swingably attached to the distal end portion of the arm 7.

  The boom 6 is raised and lowered by the expansion and contraction operation of the boom cylinder 9, the arm 7 is swung by the expansion and contraction operation of the arm cylinder 10, and the bucket 8 is swung with respect to the arm 7 by the expansion and contraction operation of the bucket cylinder 11. That is, in this embodiment, each cylinder 9 to 11 constitutes the actuator 12.

  FIG. 2 is a circuit diagram mainly showing a drive unit of the drive device provided in the wheeled shovel of FIG. FIG. 3 is a circuit diagram mainly showing a lock portion of the drive device provided in the wheeled shovel of FIG.

  2 and 3, the drive device 5 locks the rotation of the axle 2b, and a mode switching device 39 for switching a brake mode set in advance as operating states of a parking brake and a work brake (not shown). And a locking device 40.

  The mode switching device 39 includes a selector switch (mode switching means) 17 that can select the brake mode, and an electromagnetic valve 31 or an electromagnetic valve 32 that is excited in accordance with a selection operation of the selector switch 17.

  The changeover switch 17 cancels the operation of the W mode as a work mode for operating the parking brake and the work brake, the P mode as the parking mode for operating the parking brake and releasing the work brake, and the operation of the parking brake and the work brake. A switch that allows a specific brake mode to be selected from the D mode as the travel mode.

  The electromagnetic valve 31 is provided to supply or stop supplying hydraulic oil to an unillustrated work brake. Specifically, the solenoid valve 31 supplies air to an air cylinder (not shown) in an operation state in which power from the power source 30 is supplied to operate a drum type work brake, while there is no power supply from the power source 30. In operation, the air cylinder is opened to release the work brake.

  The electromagnetic valve 32 is provided to supply or stop supplying air to a parking brake (not shown). Specifically, the electromagnetic valve 32 presses a brake pad energized by a spring (not shown) in an operation state in which power from the power source 30 is not supplied, and operates the parking brake, while power from the power source 30 is supplied. In the operated state, air is supplied to an air cylinder (not shown) and the brake pad is moved to release the operation of the parking brake.

  The lock device 40 can input and operate a drive unit (travel drive unit, undulation drive unit) 14 that supplies power to the axle 2b and the actuator 12, and an instruction for causing the drive unit 14 to travel the lower traveling body 2. Power supply to the axle 2b by the shift lever (running input unit) 15, the operation lever (raising / lowering input unit) 16 capable of inputting an instruction for raising and lowering the attachment 4 to the drive unit 14, and the drive unit 14. And a lock portion 18 that locks the drive portion 14 so as to be in a disabled state.

  The drive unit 14 includes a hydraulic motor 19 that rotationally drives the axle 2 b, an actuator 12 that raises and lowers the attachment 4, and a hydraulic circuit 20 that supplies hydraulic oil to the hydraulic motor 19 and the attachment 4.

  The hydraulic circuit 20 supplies a main oil (hydraulic pump) 23 that supplies hydraulic oil to the hydraulic motor 19 via the three-position switching valve 21 and supplies hydraulic oil to the actuator 12 via the three-position switching valve 22. The hydraulic oil is supplied to the pilot ports 21a and 21b of the three-position switching valve 21 through the position switching valve (electromagnetic valve) 24, and the pilot of the three-position switching valve 22 through the two-position switching valve (electromagnetic valve) 25. A pilot pump 26 that supplies hydraulic oil to the port, and a remote control valve 27 that can adjust the supply flow rate of hydraulic oil from the pilot pump 26 to the three-position switching valve 21 are provided.

  Further, the hydraulic circuit 20 is provided with the operation lever 16, and the operation lever 16 supplies the hydraulic oil supplied from the pilot pump 26 to one of the pilot port 22 a and the pilot port 22 b of the three-position switching valve 22. By supplying, the actuator 12 can be expanded and contracted. Reference numerals 28 and 29 in FIG. 2 are relief valves.

  The main pump 23 and the pilot pump 26 are each composed of a variable displacement pump and a low displacement pump that generate hydraulic pressure by driving an engine (not shown).

  The three-position switching valve 21 is held at the neutral position C when no hydraulic oil is supplied to either the pilot port 21a or the pilot port 21b, and is switched to the switching position A when the hydraulic oil is supplied to the pilot port 21a. When the hydraulic oil is supplied to the pilot port 21b, it is switched to the switching position B.

  In the neutral position C, the supply of hydraulic oil from the main pump 23 to the hydraulic motor 19 is stopped, while in the switching positions A and B, the hydraulic oil is supplied from the main pump 23 to the hydraulic motor 19 and the hydraulic motor 19 is supplied. Drive. At the switching position A, the hydraulic motor 19 is driven in the direction in which the lower traveling body 2 moves forward, while at the switching position B, the hydraulic motor 19 is driven in the direction in which the lower traveling body 2 moves backward.

  Further, the three-position switching valve 21 supplies hydraulic oil to the hydraulic motor 19 by changing the stroke from the neutral position C to the switching position A or B depending on the pilot pressure of the hydraulic oil to the pilot ports 21a and 21b. The flow rate can be adjusted.

  The three-position switching valve 24 is held at the neutral position F when there is no electrical input to either the solenoid 24a or the solenoid 24b, and is switched to the switching position D when there is an input to the solenoid 24a, and the solenoid 24b has an input. And can be switched to a switching position E.

  In the neutral position F (stop position), the supply of hydraulic oil from the pilot pump 26 to the pilot ports 21a and 21b is stopped, while in the switching position D and E (supply position), the pilot port 21a, The hydraulic oil to 21b is supplied and the 3 position switching valve 21 is operated.

  Specifically, hydraulic oil from the pilot pump 26 is supplied to the pilot port 21a at the switching position D, while hydraulic oil is supplied from the pilot pump 26 to the pilot port 21b at the switching position E.

  When the remote control valve 27 is operated according to the depression operation of the accelerator pedal 27a in the state of the switching position D or E as described above, the three-position switching valve 21 is operated according to the depression amount. Become.

  The three-position switching valve 22 is held at the neutral position I when no hydraulic oil is supplied to either the pilot port 22a or the pilot port 22b, and is switched to the switching position G when the hydraulic oil is supplied to the pilot port 22a. When the hydraulic oil is supplied to the pilot port 22b, it is switched to the switching position H.

  In the neutral position I, the supply of hydraulic oil from the main pump 23 to the actuator 12 is stopped, while in the switching positions G and H, the hydraulic oil is supplied from the main pump 23 to the actuator 12 and the actuator 12 expands and contracts.

  The two-position switching valve 25 is held at the normal position K when there is no electrical input to the solenoid 25a, and is switched to the switching position J when there is an electrical input to the solenoid 25a.

  At the normal position K (stop position), the supply of hydraulic oil from the pilot pump 26 to the operation lever 16 side is stopped, while at the switching position J (supply position), the operation is performed from the pilot pump 26 to the operation lever 16 side. Oil is supplied. When the operation lever 16 is tilted in the left or right direction from the neutral position shown in FIG. 2 in the state of the switching position J, the hydraulic oil from the pilot pump 26 is supplied to the pilot port 22a or 22b of the three-position switching valve 22. And the actuator 12 expands and contracts.

  As shown in FIG. 2, the lock unit 18 includes a power source 30 and an electric circuit 33 (see FIG. 2) provided between the power source 30 and the solenoids 24a, 24b, 25a of the three-position switching valve 24 and the two-position switching valve 25. 2), forward relay (transmission state switching means) 34, reverse relay (transmission state switching means) 35 and undulation relay (supply state switching means) 36 provided in the electric circuit 33, and these relays 34 And an auxiliary circuit 37 (see FIG. 3) for connecting the exciting coils and the changeover switch 17 to each other.

  The electric circuit 33 can supply the power of the power source 30 to the solenoid 24a or 24b via the forward relay 34 or the reverse relay 35 according to the operation of the shift lever 15. That is, when the shift lever 15 is operated to the forward side (drive position), the power source 30 and the forward relay 34 are electrically connected, while when the shift lever 15 is operated to the reverse side (back position), the power source is supplied. 30 and the reverse relay 35 are electrically connected.

  Further, the electric circuit 33 can supply the power of the power supply 30 to the solenoid 25a via the undulation relay 36.

  The forward relay 34 includes a coil 34a and a switch 34b that is closed when the open coil 34a is excited in a state where the coil 34a is not excited, and both contacts of the switch 34b are respectively connected to the forward side of the shift lever 15. Or a solenoid 24a of the three-position switching valve 24.

  The reverse relay 35 includes a coil 35a and a switch 35b that closes when the open coil 35a is excited while the coil 35a is not excited, and both contacts of the switch 35b are respectively connected to the reverse side of the shift lever 15. Or a solenoid 24b of the three-position switching valve 24.

  The undulation relay 36 includes a coil 36a and a switch 36b that closes when the opening coil 36a is excited while the coil 36a is not excited, and both contacts of the switch 36b are on the reverse side of the shift lever 15, respectively. Or a solenoid 25a of the two-position switching valve 25.

  As will be described below, the auxiliary circuit 37 can supply the power of the power source 30 to the coils 34a to 36a of the relays 34 to 36 in accordance with the switching state of the brake mode by the changeover switch 17.

  Hereinafter, the operation at the time of switching the brake mode by the changeover switch 17 will be described with reference to FIGS.

  FIG. 4 is a list showing the state of each relay and brake according to the switching of the brake mode.

(1) When the brake mode is switched to the W mode Terminal # 1 and terminal # 2 of the changeover switch 17 are connected, and the electromagnetic valve 31 connected to the terminal # 2 is operated, while the auxiliary circuit 37 The diode 38a provided prevents the power supply to the solenoid valve 32.

  Accordingly, in the W mode, the work brake and the parking brake are activated.

  In the W mode, power (mode selection signal) from the power supply 30 is supplied to the coil 36 a of the undulating relay 36 via the auxiliary circuit 37. As a result, the switch 36b is closed and the two-position switching valve 25 is operated to the switching position J, so that the hydraulic oil from the pilot pump 26 is supplied to the operation lever 16.

  Therefore, in the W mode, the actuator 12 can be operated by operating the three-position switching valve 22 in accordance with the tilting operation of the operation lever 16.

  On the other hand, in the W mode, supply of electric power (mode selection signal) to the solenoids 34b and 35b of the forward relay 34 and the reverse relay 35 is blocked by the diode 38a. The electrical connection with 24a, 24b is released.

  Therefore, in the W mode, the three-position switching valve 24 maintains the neutral position F regardless of the operation of the shift lever 15 and the operation of the hydraulic motor 19 is blocked.

(2) When the brake mode is switched to the P mode Although the terminal # 1 and the terminal # 3 of the changeover switch 17 are connected, the solenoid valves 31, 32 are not connected to the terminal # 3. Supply of electric power to both the solenoid valves 31 and 32 is blocked.

  Therefore, in the P mode, the operation of the work brake is released and the parking brake is activated.

  In this P mode, since the auxiliary circuit 37 is not connected to the terminal # 3, supply of power (mode selection signal) from the power source 30 to the coils 34a to 36a of the relays 34 to 36 is blocked. As a result, the switches 34b to 36b are kept open, and the hydraulic motor 19 and the actuator 12 are prevented from operating.

  That is, since the power supply to the forward and reverse relays 34 and 35 is blocked, the electrical connection between the shift lever 15 and the solenoids 24a and 24b of the three-position switching valve 24 is released. Regardless of the operation of the lever 15, the three-position switching valve 24 maintains the neutral position F, and the operation of the hydraulic motor 19 is blocked.

  Further, the power supply to the hoisting relay 36 is blocked, so that the electrical connection between the power source 30 and the solenoid 25a of the two-position switching valve 25 is released, and the two-position switching valve 25 moves to the normal position K. Since the supply of hydraulic oil from the pilot pump 26 to the operation lever 16 is stopped, the hydraulic oil is supplied from the pilot pump 26 to the three-position switching valve 22 regardless of the operation of the operation lever 16. Accordingly, the operation of the actuator 12 is blocked.

(3) When the brake mode is switched to the D mode: Terminal # 1 and terminal # 4 of the changeover switch 17 are connected, and the electromagnetic valve 32 connected to the terminal # 4 is operated, while the auxiliary circuit 37 The diode 38b provided prevents the power supply to the electromagnetic valve 31.

  Therefore, in the D mode, the work brake and the parking brake are activated.

  In the D mode, power from the power supply 30 is supplied to the coils 34 a to 36 a of the relays 34 to 36 via the auxiliary circuit 37. Thereby, in D mode, operation of hydraulic motor 19 and actuator 12 is permitted.

  That is, when power is supplied to the forward and reverse relays 34 and 35, the shift lever 15 and the solenoids 24a and 24b of the three-position switching valve 24 are electrically connected. The hydraulic motor 19 can be operated by operating the three-position switching valve 24 according to the operation of the lever 15.

  Further, when power is supplied to the undulation relay 36, the power source 30 and the solenoid 25a of the two-position switching valve 25 are electrically connected, and the two-position switching valve 25 is set to the switching position J. Since the operation oil is supplied from the pilot pump 26 to the operation lever 16, the three-position switching valve 22 can be operated in accordance with the operation of the operation lever 16 to operate the actuator 12.

  As described above, according to the wheel-type excavator 1, since the lock portion 18 is provided, even when the operator erroneously operates the shift lever 15 when the P mode is selected as the brake mode. By locking the drive unit 14 so that power cannot be supplied to the axle 2b, it is possible to suppress an excessive load on the parking brake.

  Therefore, according to the wheel type excavator 1, the utility of the parking brake can be prolonged.

  In the wheeled excavator 1, since the power supply to the axle 2b is allowed when the brake mode is switched to the D mode, the lower traveling body 2 can travel in the D mode.

  On the other hand, when the W mode is selected as the brake mode, the drive unit 14 is locked so that the lock unit 18 cannot supply power to the axle 2b, so the W mode is selected and the work is performed. Even if the operator accidentally operates the shift lever 15 during this time, the safety can be further improved by preventing the lower traveling body 2 during the operation from traveling.

  Further, according to the wheel excavator 1, the drive unit 14 can be locked so that the power supply to the attachment 4 is disabled by the lock unit 18, so that the P mode is selected as the brake mode. Even if the operator erroneously inputs the operation lever 16, the situation where the lower traveling body 2 moves due to the reaction force of the work can be suppressed by preventing the work by the attachment 4. It is possible to suppress an excessive load from being generated in the parking brake.

  According to the wheeled excavator 1 according to the embodiment, since the forward relay 34 and the reverse relay 35 are provided, the state where the transmission of the output signal from the shift lever 15 to the three-position switching valve 24 is allowed is stopped. An operation for switching between states (opening / closing operation of the switches 34b and 35b) can be performed based on the presence / absence of power supply from the changeover switch 17 without requiring special control.

  Further, according to the wheeled excavator 1 according to the above embodiment, since the undulation relay 36 is provided, the operation of switching the two-position switching valve 25 to the supply position or the stop position (opening / closing operation of the switch 36b) Based on the presence or absence of the power supply from 17, it can carry out without requiring special control.

It is a side view which shows the wheel type shovel which concerns on embodiment of this invention. It is a circuit diagram which mainly shows a drive part among the drive devices provided in the wheel type shovel of FIG. It is a circuit diagram which mainly shows a locking part among the drive devices provided in the wheel type shovel of FIG. It is a table | surface which shows the state of each relay and brake according to switching of the brake mode.

Explanation of symbols

1 Wheel excavator (an example of a work machine)
2 Lower traveling body (airframe)
2b Axle 3 Upper turning body (airframe)
4 Attachment 12 Actuator 14 Drive part (travel drive part, undulation drive part)
15 Shift lever (travel input part)
16 Operation lever (undulation input part)
17 selector switch (mode switching means)
18 Locking part 19 Hydraulic motor 23 Main pump (hydraulic pump)
25 2-position switching valve (solenoid valve)
34 Forward relay (transmission state switching means)
35 Reverse relay (supply state switching means)
36 Relief relay 39 Mode switching device 40 Lock device

Claims (10)

An aircraft that travels according to the rotation of the axle, a work brake that operates to receive the supply of predetermined power to keep the axle in a stopped state, a power source that supplies power to the work brake, and a power source from the power source A parking brake that operates so as to keep the axle in a stopped state using frictional resistance without receiving the power of the vehicle, and a plurality of brake modes are prepared as operating states of the parking brake and the work brake. A lock device provided in a work machine for locking rotation of the axle,
A travel drive for supplying power to the axle;
A travel input unit capable of inputting and operating an instruction to travel the airframe to the travel drive unit;
Regardless of the input operation of the travel input unit, a lock unit that locks the travel drive unit so that power cannot be supplied to the axle ;
A hoisting drive unit for supplying hoisting power to an attachment provided in the work machine so as to be hoistable with respect to the airframe;
A undulation input unit capable of inputting and operating an instruction to undulate the attachment to the undulation drive unit ,
When the parking mode that activates the parking brake and releases the operation of the work brake is selected as the brake mode, the lock unit locks the travel drive unit, while the parking mode And when the travel mode for releasing the operation of the work brake is selected, the travel drive unit is unlocked ,
The lock unit locks the hoisting drive unit so that power supply to the attachment is disabled regardless of an input operation of the hoisting input unit when a parking mode is selected as the brake mode. The working drive is unlocked so as to allow power supply to the attachment when a work mode for operating the parking brake and work brake is selected as the brake mode . Locking device.   2. The work machine lock device according to claim 1, wherein the lock unit locks the travel drive unit when a work mode for operating the parking brake and the work brake is selected as the brake mode. .   The travel input unit is configured to output an instruction for causing the vehicle to travel as an electrical signal to the travel drive unit, and the lock unit transmits an electrical signal from the travel input unit to the travel drive unit. 3. The work machine lock device according to claim 1, wherein the traveling drive unit is locked by blocking.   It further comprises mode switching means capable of selecting the brake mode and outputting a mode selection signal corresponding to the mode when a specific mode is selected, and the lock unit outputs from the mode switching means And a transmission state switching means for switching a transmission state between a state in which transmission of the electric signal is blocked and a state in which transmission of the electric signal is allowed based on the presence or absence of a mode selection signal to be performed. The work machine locking device according to claim 3. The locking device according to any one of claims 1 to 4, an airframe that travels according to rotation of an axle, and a work brake that operates to receive a predetermined power supply to keep the axle in a stopped state. A power source that supplies power to the work brake, a parking brake that operates to keep the axle in a stopped state by using frictional resistance without receiving power from the power source, and the parking brake; Mode selection means capable of selecting a brake mode set in advance as an operation state of the work brake, and the brake mode includes a parking mode, a parking brake, and a work for operating the parking brake and releasing the operation of the work brake. A travel mode for releasing the brake and a work mode for operating the parking brake and the work brake. Work machine. An aircraft that travels according to the rotation of the axle, an attachment that can be raised and lowered with respect to the aircraft, a work brake that operates to keep the axle in a stopped state by receiving a predetermined power supply, and the work brake A power source that supplies power to the vehicle, and a parking brake that operates to keep the axle in a stopped state by using frictional resistance without receiving power from the power source. A locking device provided on a work machine having a plurality of brake modes as an operating state, and for locking up and down the attachment;
A hoisting drive for supplying hoisting power to the attachment;
An undulation input unit capable of inputting and operating instructions for raising and lowering the attachment to the undulation drive unit,
Regardless of the input operation of this undulation input unit, comprising a lock unit that locks the undulation drive unit so that power supply to the attachment is disabled,
When the parking mode that activates the parking brake and releases the operation of the work brake is selected as the brake mode, the lock unit locks the undulation drive unit, while the parking mode And when the work mode which operates a work brake is selected, the lock | rock of the said undulation drive part is cancelled | released, The locking device of the working machine characterized by the above-mentioned. The undulation drive unit includes a hydraulic pump and an actuator that receives the supply of hydraulic oil from the hydraulic pump to cause the attachment to undulate, and the undulation input unit adjusts hydraulic pressure supplied from the hydraulic pump to the actuator. It is configured to be operable, and the lock unit locks the undulation drive unit so that the hydraulic oil cannot be supplied from the hydraulic pump to the actuator regardless of the operation of the undulation input unit. The working machine locking device according to claim 6. The undulation drive unit includes an electromagnetic valve capable of switching between a supply position that allows supply of hydraulic oil from the hydraulic pump to the actuator and a stop position that stops supply of hydraulic oil to the actuator, and the lock unit 8. The work machine lock device according to claim 7, wherein power supplied to the solenoid valve is adjusted so that the solenoid valve is in a stop position in response to the parking mode being selected. It further comprises mode selection means capable of selecting the brake mode and outputting a mode selection signal corresponding to the mode when a specific mode is selected, and the lock unit outputs from the mode selection means Supply state switching means for switching the state of power supply to the electromagnetic valve between a state in which the electromagnetic valve is operated to the supply position and a state in which the electromagnetic valve is operated to the stop position based on the presence or absence of a mode selection signal 9. The work machine lock device according to claim 8, further comprising: The lock device according to any one of claims 6 to 9, an airframe that travels in response to rotation of an axle, an attachment that is mounted on the airframe in an undulating manner, and a predetermined power supply to receive the A work brake that operates to keep the axle in a stopped state, a power source that supplies power to the work brake, and a state in which the axle is stopped using frictional resistance without receiving power from the power source. And a mode selection means capable of selecting a brake mode set in advance as operating states of the parking brake and the work brake. In the brake mode, the parking brake is operated and the work brake is operated. Work characterized by including at least a parking mode for releasing the operation and a work mode for operating the parking brake and the work brake.械.

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