JP5205227B2 - Work machine operating device for work vehicle - Google Patents

Description

  The present invention relates to a work machine operation device, and more particularly to an operation device for operating a work machine provided in a work vehicle such as a bulldozer.

  A bulldozer as a work vehicle includes a blade disposed in front. The blade can be moved in each direction by a lift cylinder, an angle cylinder, and a tilt cylinder to which hydraulic pressure is supplied by an operator's operation. Specifically, the blade is driven up and down by the expansion and contraction operation of the left and right lift cylinders mounted on the left and right sides of the body frame. In addition, the blades are angle-driven back and forth by the expansion and contraction of the left and right angle cylinders mounted on the left and right sides of the work machine frame, and the blades are moved up and down by the expansion and contraction of the tilt cylinder mounted on the tip of the work machine frame. (For example, Patent Document 1).

As a form of lever for operating the blade, as shown in Patent Document 2, there has been proposed an apparatus in which a plurality of push buttons are provided on the head of the operation lever to improve workability.
JP 2006-257727 A JP-A-8-270017

  Here, the following two types of operation systems for executing the angle operation of the blade are conceivable and have already been adopted in actual machines.

  (1) An operation member for angle operation is provided on the operation lever, and the operation member is a proportional type in which the operation stroke and the operation speed are proportional to each other. The control valve for supplying pressure oil to the angle cylinder is also a control signal from the controller The flow rate control valve is controlled in proportion to the flow rate.

  (2) An operation member for angle operation is provided on the operation lever, the operation member is an on / off type switch, and a control valve for supplying pressure oil to the angle cylinder is also an on / off type flow control valve.

  Here, as a result of investigating the operation status of the bulldozer operator, it has been found that the operator always operates up to the maximum stroke even though a proportional type operation member is provided. That is, there is almost no work for adjusting the operation speed by the switch stroke.

  On the other hand, if the control valve that supplies pressure oil to the angle cylinder is an on / off type flow control valve, the angle operation starts and stops suddenly, and there is a problem that a shock occurs during operation. is there.

  An object of the present invention is to provide an operating device that is inexpensive and has good operability, and that can suppress a shock during operation of a work implement.

  Another object of the present invention is to improve the operability of an operation member such as an operation lever.

A work machine operating device for a work vehicle according to a first aspect of the present invention is an operation device for operating a work machine provided on the work vehicle, wherein at least one hydraulic cylinder for driving the work machine, An on / off switch for instructing driving or stopping, a controller for receiving a signal from the on / off switch and outputting a control signal for controlling the supply of pressure oil to the hydraulic cylinder, and a control signal from the controller and a, a flow control valve for controlling the flow rate of the hydraulic fluid to the hydraulic cylinders in proportion to. The controller outputs a modulation control signal to the flow control valve so that the flow rate of the pressure oil to the hydraulic cylinder gradually increases or decreases when the controller is turned on and off by the on / off switch. This is a signal such that the rate of decrease in the flow rate of the pressure oil at the time of turning off becomes larger than the rate of increase in the flow rate at the time of on.

  In this device, the working machine is driven and stopped by an on / off switch. A signal from the on / off switch is input to the controller, and a control signal for controlling the supply of pressure oil to the hydraulic cylinder is output from the controller. In the flow rate control valve, the flow rate of the pressure oil to the hydraulic cylinder is controlled in proportion to the control signal from the controller, and the pressure oil whose flow rate is controlled is supplied to the hydraulic cylinder.

Here, since the switch for instructing the operation of the work machine is an on / off switch, it is less expensive than a switch of a type in which the switch stroke and the operation speed are proportional. Further, since the on / off switch can be operated with a shorter stroke than the proportional type switch, the operability is improved. On the other hand, hydraulic oil with a flow rate controlled in proportion to the control signal from the controller is supplied to the hydraulic cylinder, so that the operating speed of the hydraulic cylinder can be adjusted and the shock during operation of the work implement can be suppressed. It is Ru can.

In addition, when the on / off switch is turned on and off, that is, when the work machine starts operating or stops operating, the flow rate of the pressure oil gradually increases or decreases. Ru can be suppressed.

Here, the control of the pressure oil at the time of turning off, that is, the return side is related to the stop position of the work implement. And it is desirable that the stop position of the work machine is not so far from the position that the operator wants to stop. Therefore, the rate of decrease in the flow rate of the pressure oil at the time of turning off is increased, that is, the degree of modulation is reduced, so that the work implement stops at a desired position.

A work machine operating device for a work vehicle according to a second invention is the device according to the first invention , wherein the work machine is a bulldozer blade. The hydraulic cylinder has an angle cylinder for operating the blade at an angle and a tilt cylinder for operating the blade for tilting.

  Here, it becomes easy to perform the angle and tilt operations simultaneously.

A work machine operating device for a work vehicle according to a third invention is the device according to the second invention, wherein the on / off switch has a signal for instructing an angle operation by one operation portion and one operation of one operation portion. An angle terminal unit that outputs to the controller, and a tilt terminal unit that outputs a signal for instructing a tilt operation by another operation of one operation unit to the controller.

  In this case, since the angle operation and the tilt operation can be operated by one operation unit, the operability is improved.

A work machine operating device for a work vehicle according to a fourth aspect of the present invention is the device according to any one of the first to third aspects, further comprising an operation lever operable in a plurality of directions for operating the work machine. The on / off switch is provided at a part of the operation lever.

  Here, since the ON / OFF switch is provided in a part of the operation lever, the operation of the work machine becomes easy.

A work machine operating device for a work vehicle according to a fifth invention is the device according to the fourth invention, wherein the on / off switch is arranged at a position where the operator can operate the operating lever at the same time.

  In this case, the operation of the work machine by the operation lever and the operation of the work machine by the on / off switch can be performed at the same time, and the operability is improved.

A work machine operating device for a work vehicle according to a sixth aspect of the invention is a device for operating a work machine provided in the work vehicle, wherein at least one hydraulic cylinder for driving the work machine and driving of the work machine are provided. Alternatively, an on / off switch for instructing a stop, a controller that receives a signal from the on / off switch and outputs a control signal for controlling the supply of pressure oil to the hydraulic cylinder, and a control signal from the controller A flow rate control valve that proportionally controls the flow rate of the pressure oil to the hydraulic cylinder. The working machine is a bulldozer blade, and the hydraulic cylinder has an angle cylinder for operating the blade at an angle and a tilt cylinder for operating the blade at a tilt. The flow rate control valve has an angle flow rate control valve and a tilt flow rate control valve that control the flow rate of pressure oil to the angle cylinder and the tilt cylinder in proportion to the control signal from the controller, respectively. An angle modulation signal and a tilt modulation signal are output to the angle flow control valve and the tilt flow control valve so that the flow rate of the pressure oil to the angle cylinder and the tilt cylinder gradually increases or decreases when the switch is turned on and off. The angle modulation signal and the tilt modulation signal are set such that the degree of modulation is smaller in the tilt operation than in the angle operation.

  In this case, in the angle operation and the tilt operation, it is possible to suppress a shock at the time of starting and stopping the work machine, and it is possible to make the tilt operation relatively quick.

  The operation device of the present invention as described above can be realized with an inexpensive configuration, has good operability, and can suppress a shock during operation of the work implement.

  FIG. 1 shows a part of a bulldozer that employs an operating device for a working machine according to an embodiment of the present invention. Here, a blade will be described as an example of a work machine.

[overall structure]
The bulldozer 1 includes a body frame 2, left and right track frames 3a and 3b, and a work machine frame 4 provided between the frames 3a and 3b. A blade 5 is supported on the work machine frame 4.

  Left and right lift cylinders 6a and 6b are provided on the left and right sides of the body frame 2, and the blades 5 are driven up and down via the work machine frame 4 by the expansion and contraction of the lift cylinders 6a and 6b. (See FIG. 5A). In addition, left and right angle cylinders 7a and 7b are provided on the left and right sides of the work machine frame 4, and the blade 5 can be angled back and forth by the expansion and contraction of the angle cylinders 7a and 7b. FIG. 5 (c): see blade plan view). Further, a tilt cylinder 8 is provided at the front end of the work machine frame 4, and the blade 5 is tilted up and down by the expansion and contraction of the tilt cylinder 8 (FIG. 5B: blade). See front view). Each cylinder is hydraulically operated, and each cylinder is connected to each cylinder by a flow rate control valve for supplying or discharging pressure oil and hydraulic piping.

[Control lever]
Although not shown in FIG. 1, the bulldozer 1 is provided with a cab (operating room). FIG. 2 shows the front portion of the right armrest 10 of the operator seat in the cab. An operation lever 11 for operating the blade 5 is disposed in a front portion of the right armrest 10 of the operator seat.

  FIG. 3 shows details of the operation lever 11. The operation lever 11 includes a lever main body 14, a floating switch 15 provided on the head of the lever main body 14, and an angle / tilt switch 16. The operation lever 11 allows the blade 5 to be lifted as shown in FIG. 5A, angled as shown in FIG. 5C, and tilted as shown in FIG. 5B. It is.

  The lever main body 14 has a base portion 14a formed at the lowest position, a cylindrical grip portion 14b, and a disc-shaped head portion 14c provided at the uppermost portion of the grip portion 14b. The grip portion 14b extends obliquely upward from the base portion 14a, that is, in a direction approaching the operator. The blade can be moved up and down by operating the lever body 14 back and forth as shown by arrows AB in FIG. Specifically, the operator can lower the blade 5 by operating the lever body 14 from the neutral position N to the A (front) direction, and conversely, by operating the lever body 14 from the neutral position N to the B (rear) direction. The blade 5 can be raised. Note that, when the operator does not operate the operation lever 11, the operation lever 11 returns to the neutral position N.

  The floating switch 15 is disposed above the head 14c of the lever body 14. By pushing the floating switch 15, the blade 5 can be freely moved in the up and down direction according to the action of external force.

  The angle / tilt switch 16 has a cross shape, and is disposed below the floating switch 15 in the head portion 14 c of the lever body 14. The angle / tilt switch 16 is a switch provided separately from the lever main body 14 in the same manner as the floating switch 15 and can be operated regardless of the operation of the lever main body 14.

  The angle / tilt switch 16 will be described in more detail with reference to FIGS. FIG. 4 is a view schematically showing a state where the operator views the angle / tilt switch 16 while sitting on the seat. The angle / tilt switch 16 is an on / off type switch, and includes one cross-shaped operation unit 17 and four terminals 18a to 18d provided below the one operation unit 17. ing. Since one operation portion 17 has a cross shape, it has first to fourth protrusions 17a to 17d, and the following operations are possible by pressing these protrusions 17a to 17d.

First protrusion 17a: Left tilt operation for lowering the left side of the blade 5 as viewed from the operator Second protrusion 17b: Right tilt operation for lowering the right side of the blade 5 as viewed from the operator Third protrusion 17c: The tilt of the blade 5 as viewed from above Left angle operation for tilting the left side backward Fourth projection 17d: Right angle operation for tilting the right side of the blade 5 backward as viewed from above The four terminals 18a to 18d are respectively the corresponding first projection 17a to fourth projection 17d. It is arranged below, and when the projections 17a to 17d are pushed, the corresponding switch is turned on, and when the push operation is released, the corresponding switch is turned off. And the controller 20 receives the signal from each terminal 18a-18d by switch operation, and recognizes ON or OFF of each terminal 18a-18d.

  With the configuration of the operation lever 11 as described above, the operator can operate the floating switch 15 or the angle / tilt switch 16 with the thumb while holding the grip portion 14b of the lever main body 14 with the right hand.

[Configuration of operation device]
FIG. 6 shows a schematic configuration of the operating device. As shown in this figure, an angle valve 22, a tilt valve 23, and a lift valve 24 are provided to cause the blade 5 to perform an angle operation, a tilt operation, and a lift operation. Each of the valves 22 to 24 is connected to a corresponding cylinder via a hydraulic pipe, and supplies pressure oil to the corresponding cylinder and discharges the oil from each cylinder. Each of these valves 22 to 24 is a flow control valve that supplies pressure oil having a flow rate proportional to the command current supplied from the controller 20 to the corresponding cylinder. Specifically, each of the valves 22 to 24 supplies an EPC valve that supplies a pilot pressure in proportion to the current from the controller 20, and pressure oil having a flow rate that is proportional to the pilot pressure from the EPC valve to a corresponding cylinder. And a valve body.

  The controller 20 has a function of performing modulation control as shown in FIG. 7 with respect to the angle operation and the tilt operation. That is, FIG. 7 shows the signal waveform inputted from the angle / tilt switch 16 on the lower side, and shows the target moving speed of the blade 5 when the angle operation or tilt operation is executed on the upper side. Here, the vertical axis (output: speed ratio) shown on the upper side of FIG. 7 represents the ratio (ratio) to the maximum speed of the angle operation and the tilt operation.

  In the upper signal waveform of FIG. 7, the characteristic indicated by the solid line indicates the speed ratio of the angle operation, and the characteristic indicated by the broken line indicates the speed ratio of the tilt operation.

  In the angle operation, modulation control for gradually increasing or decreasing the speed is executed in order to reduce the shock at the time of starting and stopping. Specifically, when the angle / tilt switch 16 is turned on from the controller 20 to the angle valve 22 (more precisely, the EPC valve), the flow rate of pressure oil to the angle cylinders 7a and 7b gradually increases. When it is off, the control current is output so that the flow rate of the pressure oil gradually decreases. Here, as is apparent from the characteristic indicated by the solid line in FIG. 7, the degree of modulation at the time of off is made smaller than that at the time of on, for the following reason. That is, the modulation control when off affects the stop position of the work machine. And it is desirable that the stop position of the work machine is not so far from the position that the operator wants to stop. Therefore, the rate of decrease in the flow rate of the pressure oil at the time of turning off is increased, that is, the degree of modulation is reduced, so that the work implement stops at a desired position.

  Similarly, in the tilt operation, modulation control is executed in order to reduce the shock at the time of starting and stopping. In this case, as is apparent from the characteristics indicated by the broken line in FIG. 7, the degree of modulation is small both when on and when compared to the angle operation. This is because the tilt operation requires a quicker movement than the angle operation.

[Operation]
Next, the operation will be described.

<Lift operation>
When performing the lift operation, the operator operates the operation lever 11 back and forth. When the operation lever 11 is operated in the forward direction (the direction of arrow A in FIG. 2), the controller 20 that receives a signal from the operation lever 11 outputs a current to the lift valve 24. Thereby, the pressure oil from the hydraulic pump is supplied via the lift valve 24 so that the rods of the cylinders protrude from the left and right lift cylinders 6a and 6b. As a result, the blade 5 is lowered.

  On the other hand, when the operating lever 11 is operated backward (in the direction of arrow B in FIG. 2), the controller 20 that receives a signal from the operating lever 11 sends the signal to the lift valve 24, and the lift valve 24 is opposite to the above. Output current so that it is in position. Thereby, the pressure oil from the hydraulic pump is supplied via the lift valve 24 so that the rods of the respective cylinders are retracted to the left and right lift cylinders 6a and 6b. Thereby, the blade 5 rises.

<Tilt operation>
When performing a tilt operation, the operator operates an angle / tilt switch 16 provided on the head of the operation lever 11. When the first protrusion 17a of the angle / tilt switch 16 is pressed, the first terminal 18a is turned on. The controller 20 that receives the signal from the first terminal 18 a outputs a current to the tilt valve 23. Thus, the pressure oil from the hydraulic pump is supplied to the tilt cylinder 8 via the tilt valve 23 so that the rod moves backward. Thereby, the left side of the blade 5 is lowered in front view.

  On the other hand, when the second protrusion 17b of the angle / tilt switch 16 is pressed, the second terminal 18b is turned on. Upon receiving the signal from the second terminal 18b, the controller 20 outputs a current to the tilt valve 23 so that the tilt valve 23 is in the opposite position. Thereby, the pressure oil from the hydraulic pump is supplied to the tilt cylinder 8 via the tilt valve 23 so that the rod projects. Thereby, the right side of the blade 5 is lowered in front view.

  In the tilt operation as described above, the signal input to the controller 20 from each terminal 18a, 18b is a square wave having a sudden rise as shown in the lower side of FIG. However, since the controller 20 performs modulation control as shown in FIG. 7, the pressure oil from the hydraulic pump is gradually supplied to the tilt cylinder 8 via the tilt valve 23, so that the rod of the tilt cylinder 8 is also moved. Discharge gradually. Thereby, as shown by the upper broken line in FIG. 7, the moving speed of the blade 5 gradually increases, and the shock at the time of activation is reduced.

  When stopping the tilt operation, the pressing operation of the angle / tilt switch 16 is released. At this time, similarly to the case where the angle / tilt switch 16 is turned on, the signal waveform inputted to the controller 20 from each terminal 18a, 18b is a square wave as shown in the lower side of FIG. However, similarly to the above, since the modulation control is executed by the controller 20 even when it is off, the pressure oil is gradually supplied to the tilt cylinder 8. For this reason, the shock can be reduced even when the tilting operation of the blade 5 is stopped.

<Angle operation>
When performing an angle operation, the operator operates an angle / tilt switch 16 provided on the head of the operation lever 11. When the third protrusion 17c of the angle / tilt switch 16 is pushed to perform the left angle operation, the third terminal 18c is turned on. At this time, the signal input from the third terminal 18c to the controller 20 is a square wave having a sharp rise as shown in the lower side of FIG. However, since the controller 20 performs the modulation control as shown in FIG. 7, the pressure oil from the hydraulic pump gradually passes through the angle valve 22 to the bottom side of the right angle cylinder 7b and the rod side of the left angle cylinder 7a. To be supplied. As a result, the rod of the right angle cylinder 7b gradually protrudes, and the rod of the left angle cylinder 7a gradually retracts. Thereby, as shown in the upper side of FIG. 7, the moving speed of the blade 5 gradually increases and the left side moves backward. At this time, the movement speed of the blade 5 gradually increases by the modulation control, so that the shock at the time of activation is reduced.

  When the angle operation is stopped, the pressing operation of the angle / tilt switch 16 is released. At this time, similarly to the case where the angle / tilt switch 16 is turned on, the signal waveform input from the third terminal 18c to the controller 20 is a square wave as shown on the lower side in FIG. However, similarly to the above, since the modulation control is executed by the controller 20 even when the controller is off, the pressure oil is gradually supplied to the left and right angle cylinders 7a and 7b via the angle cylinder 22. For this reason, even when the angle operation of the blade 5 is stopped, the speed gradually decreases and the blade 5 stops. Therefore, the shock when the blade 5 stops can be reduced.

  The right angle operation differs from the left angle operation in that the position where the angle / tilt switch 16 is pressed differs from that in which the operation of the left and right angle cylinders 7a and 7b is opposite to the left angle operation. The other operations are the same as the left angle operation described above.

[Features of this embodiment]
In the present embodiment as described above, since the switch for instructing the operation of the blade 5 is an on / off switch, the switch stroke is short, the operability is good, and the cost is low. On the other hand, since the valve for operating each cylinder is constituted by a proportional solenoid pressure control valve, the operating speed of each cylinder can be adjusted, and a shock during the operation of the blade can be suppressed.

  In addition, the operation lever 11 has a switch that can be operated separately from the lever body, and the angle operation and the tilt operation can be performed by one operation unit, so that the operability is improved. Moreover, since the angle / tilt switch can be operated with the thumb while the operator holds the lever body, the operability is improved when various operations are performed in parallel.

[Other Embodiments]
(a) In the above embodiment, the angle / tilt switch of the operation lever 11 has a cross shape, but the shape of the angle / tilt switch is not limited to such a shape. FIG. 8 shows another embodiment of the angle / tilt switch.

  The operation lever 11 ′ shown in FIG. 8 includes a lever main body 14, a floating switch 15 provided on the head of the lever main body 14, and an angle / tilt switch 30. Similarly to the above-described embodiment, the blade 5 can be lifted, angled, and tilted by the operation lever 11 ′.

  The structure of the lever main body 14 is the same as that of the said embodiment. That is, the lever main body 14 has a base portion 14a, a grip portion 14b, and a head portion 14c. The floating switch 15 is the same as that in the above embodiment.

  The angle / tilt switch 30 has a joystick shape and is disposed below the floating switch 15 in the head portion 14 c of the lever main body 14. The angle / tilt switch 30 is a switch provided separately from the lever body 14 and can be operated regardless of the operation of the lever body 14. The configuration of the terminal portion of the angle / tilt switch 30 is substantially the same as that of the above embodiment. That is, when the angle / tilt switch 30 as a joystick is operated in four directions, the corresponding terminals are turned on / off, and the signal is input to the controller 20.

  About operation | movement, it is completely the same as that of the said embodiment.

  Furthermore, the angle / tilt switch can be constituted by a trackball type switch.

  (b) In the above-described embodiment, the operating device of the present invention is applied to the angle operation and the tilt operation. However, the present invention can be similarly applied to the work machine operation of other work vehicles. For example, the same can be applied to the operation of the ripper device.

  (c) The arrangement of the switches in the operation unit of the angle / tilt switch is not limited to the arrangement of each embodiment.

1 is an external perspective partial view of a bulldozer to which a working machine operating device according to an embodiment of the present invention is applied. The figure which shows the operating lever of the said operating device. The figure which shows the detail of an operation lever. The figure which shows the terminal structure of an angle tilt switch. The figure for demonstrating the blade operation of a bulldozer. The block block diagram of a working machine operating device. The figure for demonstrating modulation control. The figure which shows the operation lever by other embodiment.

DESCRIPTION OF SYMBOLS 1 Bulldozer 5 Blade 6a, 6b Lift cylinder 7a, 7b Angle cylinder 8 Tilt cylinder 11 Operation lever 16, 30 Angle / tilt switch 17 Operation part 18a-18d Terminal 20 Controller 22 Angle valve 23 Tilt valve 24 Lift valve

Claims (6)

An operating device for operating a work machine provided in a work vehicle,
At least one hydraulic cylinder for driving the work implement;
An on / off switch for instructing to drive or stop the working machine;
A controller that receives a signal from the on / off switch and outputs a control signal for controlling the supply of pressure oil to the hydraulic cylinder;
A flow rate control valve that controls the flow rate of pressure oil to the hydraulic cylinder in proportion to a control signal from the controller;
Equipped with a,
The controller outputs a modulation control signal to the flow control valve so that the flow rate of the pressure oil to the hydraulic cylinder gradually increases or decreases when turned on and off by the on / off switch,
The modulation control signal is a signal such that the rate of decrease in the flow rate of the pressure oil when the on / off switch is off is larger than the rate of increase in the flow rate when the on / off switch is on.
A work machine operating device for a work vehicle. The working machine is a bulldozer blade;
The hydraulic cylinder has an angle cylinder for operating the blade at an angle, and a tilt cylinder for operating the blade for tilting.
The work machine operating device for a work vehicle according to claim 1 . The on / off switch includes one operation unit, an angle terminal unit that outputs a signal for instructing an angle operation by one operation of the one operation unit, and another operation of the one operation unit. The work machine operating device for a work vehicle according to claim 2 , further comprising a tilt terminal portion that outputs a signal for instructing a tilt operation to the controller. An operation lever operable in a plurality of directions for operating the work implement;
The on / off switch is provided on a part of the operation lever.
The work machine operating device for a work vehicle according to any one of claims 1 to 3 . The work machine operating device for a work vehicle according to claim 4 , wherein the on / off switch is disposed at a position where an operator can operate the operating lever at the same time. An operating device for operating a work machine provided in a work vehicle,
At least one hydraulic cylinder for driving the work implement;
An on / off switch for instructing to drive or stop the working machine;
A controller that receives a signal from the on / off switch and outputs a control signal for controlling the supply of pressure oil to the hydraulic cylinder;
A flow rate control valve that controls the flow rate of pressure oil to the hydraulic cylinder in proportion to a control signal from the controller;
With
The working machine is a bulldozer blade;
The hydraulic cylinder has an angle cylinder for operating the blade at an angle, and a tilt cylinder for operating the blade for tilting,
The flow rate control valve includes an angle flow rate control valve and a tilt flow rate control valve that control the flow rate of pressure oil to the angle cylinder and the tilt cylinder in proportion to a control signal from the controller,
The controller controls the angle flow control valve and the tilt flow control valve so that the flow rate of pressure oil to the angle cylinder and the tilt cylinder gradually increases or decreases when the on / off switch is turned on and off. Output modulation signal for tilt and modulation signal for tilt,
Modulation signal and the tilt modulation signal the angle is toward the tilting operation as compared to the angle operation it is configured so that the degree of modulation decreases,
Working machine operating device work vehicle.

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