JP2003339206A - Controller for working machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a controller for a working machine rapidly performing lowering operation of a ground implement from a lifted inoperative position to the set operation depth and scarcely causing a ground contact shock in the working machine installed so as to freely carry out lifting and lowering operation of the ground implement with a hydraulic actuator. <P>SOLUTION: The controller for the working machine is designed to compute the deviation of the detected connected height from the set operation depth when a lowering operation command is issued. The lowering control target speed is set in a state of increasing the speed with increasing deviation and the ground implement is subjected to lowering control at the lowering control target speed. The lowering control is performed until the ground implement is lowered to the set operation depth. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic actuator for raising and lowering a ground working device with respect to a self-propelled vehicle body, a work depth sensor for detecting a working depth of the ground working device, and a detection result by the work depth sensor. Based on the above, the present invention relates to a control device for a working machine, which is provided with a control means for executing a work depth control for operating the hydraulic actuator so that the work depth of the ground work device becomes a set work depth.

[0002]

2. Description of the Related Art In the above-mentioned working machine, when starting work such as turning at a ridge and entering the work of the next work line, the work equipment which has been raised to a non-working state above ground is lowered. While running. Therefore, if the descending speed of the work device is slow, the work device has not yet descended to the work level even when the work start position is reached, and a work leakage portion where the work device is not performing work is created. On the contrary,
If the work device is lowered at a high speed so that a work leakage point is less likely to occur, the impact when the work device is grounded becomes large. Therefore, conventionally, as shown in FIGS. 4 (a) and 4 (b), the larger the deviation between the connecting height of the work device to the vehicle body and the control target height set on the ground, the larger the control target speed of the hydraulic actuator. Set this control target speed on the basis of the deviation in the state of becoming large, the higher the work device is from the ground, the faster it descends, and the closer it gets to the ground, the slower it descends, so that it quickly and slowly moves on the ground. In some cases, the vehicle was controlled to descend to the set working depth at a constant descending speed with no change in speed after reaching the ground and reaching the ground.

[0003]

Conventionally, when a work is started, a descending work device suddenly changes its speed on the ground, so that a shock is likely to occur.

An object of the present invention is to provide a control device for a working machine that can quickly lower the working device to a set working depth while suppressing the occurrence of impact due to the above-mentioned stoppage and speed change.

[0005]

The constitution, action and effect of the invention according to claim 1 are as follows.

[Structure] A hydraulic actuator for vertically moving the ground work device with respect to a self-propelled vehicle, a work depth sensor for detecting a work depth of the ground work device, and a ground work based on a detection result of the work depth sensor. In a control device for a working machine, which is provided with a control means for performing a working depth control for operating the hydraulic actuator so that the working depth of the working device becomes a set working depth, a command is issued to descend the ground working device. And a connecting height sensor for detecting a connecting height of the ground work device with respect to the self-propelled vehicle body, and the control means receives the command from the down commanding means, the working depth of the ground work device. Based on the deviation between the height detected by the connection height sensor and the set working depth, the larger the deviation, the larger the control target speed of the hydraulic actuator becomes. That sets the control target speed state, is arranged to perform a descending control to operate in said control target speed hydraulic actuator to the working device lowering side.

[Operation] When the descending command means is operated, the control means increases the control target speed of the hydraulic actuator as the deviation increases, based on the deviation between the height detected by the connection height sensor and the set working depth. In this state, the control target speed is set, and the descent control for operating the hydraulic actuator to the working device descending side at the control target speed is executed, and by this descent control, the ground working device descends to the set working depth. Therefore, the ground work device descends at a higher speed as it is farther away from the set work depth, lowers at a lower speed as it approaches the set work depth, and a rapid change in speed unlike the conventional one is unlikely to occur on the way. In that state, descend to the set working depth. As a result, the ground work device descends at a higher speed as it is farther away from the set work depth, lowers in a state in which a rapid speed change is unlikely to occur, and becomes slower as it approaches the set work depth. And then descends to reach the set depth.

[Effect] Therefore, since the ground work device descends at a high speed at a high level away from the set work depth, the work work device reaches the set work depth quickly, causing work leakage due to a delay in descending the work device. Work can be started while making it difficult. In addition, the ground work equipment descends as quietly as possible to prevent shocks due to speed changes and stop shocks when the work depth reaches the set work depth. So you can start working smoothly.

The structure, operation and effect of the invention according to claim 2 are as follows.

[Structure] In the structure of the present invention according to claim 1, a characteristic change for giving a control characteristic change command to the control means so that the control means sets the control target speed corresponding to the deviation by increasing / decreasing the speed. Means are provided.

[Operation] When the characteristic changing means is operated, the control means adjusts and sets the control target speed for the deviation to the speed increasing or decelerating side, and even if the deviation is the same as before the operation, the hydraulic cylinder Since the lowering control of the ground working device is performed by operating the hydraulic cylinder such that the operating speed of the ground working device is accelerated or decelerated, the lowering control of the lowering control executed by the control means to lower the ground working device to the set working depth is performed. The characteristics can be changed such that the descending start speed of the ground work device becomes faster or slower.

[Effect] Therefore, in the case where the ground work device is comparatively light in weight and is less likely to be impacted when the descent is started, the descent start speed is adjusted so as to speed up the work device to the set working depth. When lowering or when the ground work device is relatively heavy and is likely to generate an impact when the descent is started, adjust the descent start speed to a slow speed and gently lower the work device so that vibrations of the car body do not occur. By adjusting the control characteristics, the working device can be operated appropriately.

The structure, operation, and effect of the invention according to claim 3 are as follows.

[Structure] In the structure of the invention according to claim 1 or 2, there is provided a second descending command means for commanding a descending operation of the ground working device and a control target descending position, and the control means is controlled in an automatic control mode and a manual control. And a control switching means for switching to the mode, wherein the control means executes the working depth control and the descending control when switched to the automatic control mode, and the connection height sensor is operated when switched to the manual control mode. Based on the deviation between the detected height and the control target descent position by the second descent command means, the greater the deviation, the greater the control target speed of the hydraulic actuator becomes, and the above-mentioned control target speed is set. A second actuating hydraulic actuator at the control target speed toward the work device lowering side so that the device is at the control target lowering position;
The descent control is executed, and the maximum speed of the control target speed to be set is changed based on a control characteristic change command from the characteristic changing means.

[Operation] When the control mode switching means is operated, the control means is switched to the automatic control mode to execute the working depth control and the descending control described above, or the manual control mode is operated to instruct the second descending command means. Based on, the position lowering control for operating the hydraulic cylinder to lower the ground work device is executed. When the control means is in the manual control mode,
When the characteristic changing means is operated, the maximum speed of the control target speed set based on the deviation is changed to a speed different from that before the operation to set the control target speed. As a result, when the control means is switched to the automatic control mode, the ground work device can be lowered to the set working depth by operating the descent command means. Then, when the control means is switched to the manual control mode, the ground work device can be lowered to a desired lowering position by operating the second lowering command means. At this time, if the characteristic changing means is operated, the control means is set. The maximum speed of the control target speed to be changed changes, and the work device can be lowered by changing the speed at or near the time when the ground work device starts descending.

[Effect] Therefore, in addition to the operation of lowering the ground work device to the set work depth, the operation of lowering it by a desired stroke can also be performed. Then, when performing the latter operation, when the working device starts to descend, or changing the speed in the vicinity thereof, the working device is quickly lowered to a desired position, or is adjusted to be gently lowered so as not to generate an impact. You can

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION As shown in FIG. 1, a pair of left and right steerable front wheels 1 and a pair of left and right rear wheels 2 are driven by a driving force from an engine 3 to run, and a steering wheel is provided. 4 and a rear part of a self-propelled vehicle body equipped with a driving part equipped with a driver's seat 5 and vertically swingably connected to both lateral sides of an upper portion of a mission case 6 constituting the rear part of the self-propelled vehicle body. The rotary tiller 10 is connected to the rotary tiller 10 via the link mechanism 8 including the lift arm 7 and the driving force from the engine 3 is transmitted to the rotary tiller 10 by the rotating shaft 9. By swinging the link mechanism 8 up and down by the lift arm 7, the rotary tiller 10 is lowered to a working state in which the toe side of the tiller rotor 11 has entered the soil, or tiller. Configured to over motor 11 rises operated in a non-working state of being floated from the ground, you have configured riding tiller.

A lift cylinder 2 which is a single-acting hydraulic cylinder as an example of a hydraulic actuator in which the pair of left and right lift arms 7 are provided inside the mission case 6.
It is configured so that it can be rocked by 0, and FIG.
As shown in FIG. 1, the first raising / lowering command means 3 having the driving portion 22 of the control valve 21 of the lift cylinder 20 and the raising / lowering lever 31a provided below the steering handle 4 of the driving portion.
1. Second elevating / lowering command means 32 having a position lever 32a provided on the side of the driver's seat 5 of the driver section, and control switching means 33 provided on an operation panel (not shown) provided on the side of the operator's seat 5. , Characteristic changing means 34, sensitivity setting means 35,
Plow depth setting means 36, connection height sensor 37 mounted on one of the pair of left and right lift arms 7, rotary tiller 1
Each of the tilling depth sensors 38 provided at 0 is linked to a control means 40 using a microcomputer to configure a controller for raising and lowering the rotary tiller 10 by manual operation or automatic operation. It is configured as follows.

That is, as shown in FIG. 3, the control valve 21 of the lift cylinder 20 is connected to the rolling cylinder 41.
The input port is connected to the surplus flow port of the flow priority valve 44 that supplies a constant flow rate of the pressure oil from the hydraulic pump 43 to the control valve 42 of FIG. An ascending control valve 24 connected to the oil passage 23, and an ascending pilot valve 26 connected to an operating portion of the ascending control valve 24 via a pilot oil passage 25a and equipped with an electromagnetic solenoid 26a for operation. , A lowering control valve 28 connected to the oil discharge passage 27 of the lift cylinder 20, an operating portion of the lowering control valve 28 via a pilot oil passage 25b, and an electromagnetic solenoid 29a for operation. The lowering pilot valve 29 and the relief valve 21a are provided.
That is, the electromagnetic solenoid 26 of the rising pilot valve 26
A pulse signal is supplied to the electromagnetic solenoid 29a of the down pilot valve 29 or a so that the lift cylinder 20 is operated to the upside or downside of the rotary tiller 10 and is supplied to the electromagnetic solenoids 26a and 29a. By changing and adjusting the duty cycle of the pulse signal, the lift cylinder 20 is moved to the rotary tiller 10.
The solenoid proportional control valve is configured so that the speed at which it goes up and down can be adjusted to increase or decrease.

That is, when a pulse signal is supplied to the electromagnetic solenoid 26a of the rising pilot valve 26, the rising pilot valve 26 supplies pilot hydraulic pressure to the operating portion of the rising control valve 24 to open the rising control valve 24. When operated, the control valve 21 supplies the pressure oil from the oil supply passage 45 to the lift cylinder 20 and drives the lift cylinder 20 to the rising side of the rotary tiller 10 so that the lift cylinder 20 is extended by the pressure oil. To be done. When a pulse signal is supplied to the electromagnetic solenoid 29a of the down pilot valve 29, the down pilot valve 29 supplies pilot pressure to the operating portion of the down control valve 28 to operate the down control valve 28 to the open side. The control valve 21 is driven to the descending side so that oil is drained from the lift cylinder 20 and the lift cylinder 20 is shortened to the descending side of the rotary tiller 10 by the load of the rotary tiller 10 or the like. Whether the control valve 21 is driven to the up side or the down side, when pulse currents having different duty cycles are supplied, the up control valve 24 and the down control valve 28 are opened per unit time. Is increased or decreased to increase or decrease the amount of oil supplied to the lift cylinder 20 per unit time or the amount of oil discharged from the lift cylinder 20 per unit time.
Increase or decrease the operating speed of the rising and falling sides of. When the supply of the pulse signal to the electromagnetic solenoid 26a of the ascending pilot valve 26 and the supply of the pulse signal to the electromagnetic solenoid 29a of the descending pilot valve 29 are both stopped,
The ascending pilot valve 26 releases the pilot pressure supply to the ascending control valve 24 to operate the ascending control valve 24 to the closing side, and the descending pilot valve 29 releases the pilot pressure supply to the ascending control valve 28 to make the descending control valve. By operating 28 to the closing side, the control valve 21 is brought into a neutral state so as to stop the lift cylinder 20 by stopping the oil supply to the lift cylinder 20 and the oil discharge from the lift cylinder 20. The rolling cylinder 41 is connected to one of the pair of left and right lift arms 7 of the link mechanism 8 and one of the pair of left and right lower links 8a, and the lift arm 7 is used as a reaction member to swing the lower link 8a. The rotary cultivating device 10 is rollingly operated with respect to the vehicle body by the dynamic operation.

The first elevating / lowering command means 31 is composed of the elevating / lowering lever 31a and an elevating / lowering switch 31b interlocking with the elevating / lowering lever 31a.
The lifting switch 31b is operated by swinging a, and the lifting switch 31b gives the control means 40 a command to move the rotary tiller 10 up and a command to move it down.

The second elevating / lowering command means 32 has the position lever 32a which is swingable around a lateral axis of the vehicle body.
And a potentiometer 32b whose operating portion is interlocked with the position lever 32a. When the position lever 32a is oscillated upward, the rotary cultivator 10 is operated by the potentiometer 32b operated by this. When the position lever 32b is swung to the descending side, the potentiometer 32b operated by this gives a command to the descending operation of the rotary tiller 10 to the control means 40. Position lever 32a
Regardless of whether it is operated to the ascending side or the descending side, the operation position of the position lever 32a is detected by the potentiometer 32b, and the connection height of the rotary tiller 10 corresponding to the detected operation position is adjusted to the control target ascending position or The control target lowering position is set and the control target raising position and the control target lowering position are given to the control means 40.

The control switching means 33 rotates the operating tool 33a to turn the automatic position AT and the manual position MA.
When the switch is operated to switch to the automatic position AT, an automatic mode command for switching the switch to the automatic control mode is applied to the control means 40, and when the switch is operated to the manual position MA, control is performed. A manual mode command for switching to the manual control mode and operating it is given to the means 40.

The characteristic changing means 34 is a potentiometer whose output changes according to the rotating operation of the operating tool 34a. By rotating the operating tool 34a, the rotary tilling device is operated in the automatic control mode or the manual control mode with respect to the control means 40. A command to change the control characteristic when the 10 is lowered is given.

The sensitivity setting means 35 is a potentiometer whose output changes according to the rotation operation of the operating tool 35a. By rotating the operating tool 35a, the dead zone when the control means 40 executes the automatic plowing depth control which will be described later. The width is changed to a different width and set, and this setting dead zone is output to the control means 40.

The working depth setting means 36 is a potentiometer whose output changes according to the rotating operation of the operating tool 36a. By rotating the operating tool 36a, the control means 40 maintains it when executing the automatic working depth control described later. The tilling depth to be set is set to be variable, and the set tilling depth is controlled by the control means 4
Output to 0.

The plowing depth sensor 38 is used for the rotary tiller 10.
A rotary potentiometer having an operating portion interlocked with a rotor cover 12 provided so as to cover the rear of the cultivating rotor 11. As shown in FIG. 1, the rotor cover 12 is supported so as to swing up and down with respect to the tiller frame around an axis located on the upper end side, and is urged downward by a spring 13. During operation, when the free end side touches the ground behind the tilling rotor 11 and the depth of penetration of the tilling rotor 11 into the soil changes, the tilling reaction force and the descending force of the rotor cover 12 cause tilling. It swings up and down with respect to the device frame. Therefore, the tilling depth of the tiller rotor 11 can be detected by detecting the swing angle of the rotor cover 12 with respect to the tiller frame. As a result, the tilling depth sensor 38 causes the rotary tiller 10 to rotate based on the swing angle of the rotor cover 12.
The plowing depth is detected and the detected plowing depth is converted into an electric signal and output to the control means 40.

The connection height sensor 37 is composed of a rotary potentiometer in which an operating portion is interlocked with the base end portion of the lift arm 7. When the lift arm 7 is vertically swung, the rotary tiller 10 moves up and down with respect to the self-propelled vehicle body. Therefore, by detecting the swing angle of the lift arm 7 with respect to the mission case 6, the rotary tiller 10 is detected. It is possible to detect the connection height of the vehicle body. Thereby, the connection height sensor 37 detects the connection height of the rotary tiller 10 based on the swing angle of the lift arm 7, and outputs the detected connection height to the control means 40 as an electric signal.

The control means 40 is constructed so as to operate based on the information from the above-mentioned means and sensors and the flow shown in FIGS.

That is, when the control switching means 33 is switched to the automatic position AT and the automatic mode command is input,
When the control mode is switched to the automatic control mode and the control switching means 33 is switched to the manual position MA and a manual mode command is input, the mode is switched to the manual control mode.

When switched to the automatic control mode, the first elevating / lowering command means 31, the characteristic changing means 34, the plowing depth setting means 36,
On the basis of the information from the tilling depth sensor 38 and the connection height sensor 37, the lifting control for operating the lift cylinder 20 so that the rotary tiller 10 is in the ascending non-working state or the descending working state, and the rotary tiller 10's. Performing automatic plowing depth control to maintain the plowing depth to the set plowing depth. That is, FIG.
As shown in, when the first elevating / lowering command means 31 is operated and the ascending operation command is inputted, it is judged whether or not the rotary tiller 10 is at the ascending end based on the detection information of the connection height sensor 37, and the ascending If it is not at the end, the control valve 21 is driven to the ascending side and the lift cylinder 20 is operated to the ascending side until the rotary tiller 10 is ascended to the ascending end. First
1 When the ascent / descent command means 31 is operated and the descending operation command is input, it is determined whether the rotary tiller 10 is at a connection height higher than the set plowing depth based on the detection information of the plowing depth sensor 38, and the set plowing depth is set. If the connection height is higher than the depth, the control characteristic corresponding to the control characteristic change instruction based on the control characteristic change instruction by the characteristic changing means 34 and the data input to the storage unit (shown in FIG. 4C). a, b, c, etc.) is set. Then, the deviation between the information detected by the connection height sensor 37 and the connection height corresponding to the set plowing depth is calculated, and based on this deviation and the set control characteristic, the larger the deviation, the control target speed of the lift cylinder 20. When the control target speed is set in a state in which the control valve speed becomes large, and the pulse signal of the duty cycle at which the control target speed appears is output to the drive unit 22 a signal that should be supplied to the control valve 21,
1 is driven downward by the pulse signal of the duty cycle, and the lift cylinder 20 is operated so as to operate downward at the set control target speed. The calculation of this deviation, the setting of the control target speed for the deviation, and the driving of the control valve 21 for operating the lift cylinder 20 to the descending side at the set control target speed are performed so that the tilling depth of the rotary tiller 10 becomes the set tilling depth. It goes on every time the set time elapses.

When the rotary tiller 10 descends to the set tillage depth, thereafter, the lift cylinder 20 is operated so that the tillage depth of the rotary tiller 10 becomes the set tillage depth based on the detection result of the tillage depth sensor 38. Perform automatic plowing control. That is, as shown in FIG. 8, the dead zone set by the sensitivity setting means 35 and the plowing depth detected by the plowing depth sensor 38 are input to determine whether or not the plowing depth is outside the set dead zone. For example, determine whether it is on the shallow side or the deep side. When it is determined that the lift valve 20 is on the shallow side, the control valve 21 is driven to the descending side, and the lift cylinder 20 is operated to the descending side until the tilling depth detected by the tilling depth sensor 38 reaches the tilling depth set by the tilling depth setting means 36. . When it is determined that the detected plowing depth is out of the set dead zone to the deep side, the control valve 21 is driven to the upward side and lifted until the plowing depth detected by the plowing depth sensor 38 reaches the plowing depth set by the plowing depth setting means 36. The cylinder 20 is operated upward.

When the mode is switched to the manual control mode, the second elevating / lowering command means 32, the characteristic changing means 34, and the connection height sensor 37.
Based on the information from each, position control is performed to operate the lift cylinder 20 so that the rotary tiller 10 moves up and down.

That is, as shown in FIG. 9, when the second elevating and lowering command means 32 is operated and the ascending operation command is inputted, the control target ascending position set by the second elevating and lowering command means 32 is inputted and the coupling height is increased. Based on the detection information of the height sensor 37, it is determined whether or not the rotary tiller 10 is at the control target rising position. If it is not at the control target rising position, the control valve 21 is driven to the upside, and the rotary tiller 10 is operated. The lift cylinder 20 is operated to the rising side until it rises to the control target rising position. When the second elevating and lowering command means 32 is operated and the lowering operation command is input, the control target lowering position set by the second elevating and lowering command means 32 is input, and the rotary tilling device is based on the detection information of the connection height sensor 37. It is determined whether or not 10 is at the control target lowered position. If it is not at the control target descending position, the control characteristic corresponding to the control characteristic changing instruction based on the control characteristic changing instruction by the characteristic changing means 34 and the data input to the storage unit (e, shown in FIG. 5B). (f, g, h, i, etc.) are set. Then, the deviation between the detected height by the connecting height and the control target lowering position is calculated, and based on this deviation and the set control characteristic, the larger the deviation is, the larger the control target speed of the lift cylinder 20 becomes. By setting this control target speed and outputting to the drive unit 22 a signal that causes the control valve 21 to be supplied with a pulse signal with a duty cycle that causes this control target speed to appear, the control valve 21 is pulsed with the above-mentioned duty cycle. The signal is driven to the descending side, and the lift cylinder 20 is operated to operate to the descending side at the set control target speed. The rotary tiller 10 lowers the calculation of this deviation, the setting of the control target speed for the deviation, and the driving of the control valve 21 that operates the lift cylinder 20 to the lower side at the set control target speed, to the control target lowering position. It goes up every time the set time elapses.

Therefore, if the control switching means 33 is switched to the automatic position AT and the raising / lowering lever 31a of the first raising / lowering instruction means 31 is operated to issue a raising operation instruction, the control means 40 moves the lift cylinder 20 to the raising side. When the rotary tiller 10 is operated and the lift end is reached, the lift cylinder 20 is stopped in the operating state. As a result, the rotary cultivator 10 is raised to the non-working state in which the rotary tiller 10 has reached the rising end.

From this state, if the elevating lever 31a of the first elevating command means 31 is operated to issue a descending operation command, the control means 40 operates the lift cylinder 20 to the descending side and this descending operation is performed by the rotary tiller 10. Perform till the working depth reaches the set working depth. At this time, the control means 40 is selected by the characteristic changing means 34 in a state in which the control target speed of the lift cylinder 20 becomes larger as the deviation between the height detected by the connection height sensor 37 and the set plowing depth becomes larger. 4 (c), that is, the control characteristic of the lift cylinder 20 with respect to the deviation as shown in FIG. As shown in (c), the higher the distance from the set working depth, the faster the descent, and the closer the set working depth, the slower the descent. Then, after the rotary tiller 10 has descended to the set tilling depth, the control means 4
Based on the information detected by the tilling depth sensor 38, the automatic tilling depth control for automatically moving the lift cylinder 20 up and down is executed so that the tilling depth of the rotary tiller 10 becomes the tilling depth set by the tilling depth setting means 36. . Thereby, the rotary tiller 10
Quickly descends to the working condition where the set working depth is reached, and to prevent grounding and stop impacts, and after descending to this working condition, this descending working condition is maintained regardless of the front-back inclination of the vehicle body. It is possible to perform the tilling work while making it difficult to cause work leakage due to the delay in descending the rotary tiller 10 at the start point and keeping the tilling depth at or near the set tilling depth even if the ground has irregularities.

If the control switching means 33 is switched to the manual position MA and the position lever 32a of the second elevating / lowering command means 32 is rocked to the ascending side, the control means 40 operates the lift cylinder 20 to the ascending side and the rotary. When the cultivating device 10 reaches the set control target rising position by the potentiometer 32b, the lift cylinder 20 is stopped in the operating state. As a result, the rotary tiller 10 is raised to the connecting height which is raised by the stroke corresponding to the operation stroke of the position lever 32a. When the position lever 32a of the second elevating / lowering command means 32 is oscillated to the lower side, the control means 40 operates the lift cylinder 20 to the lower side, and when the rotary tiller 10 reaches the set control target lower position by the potentiometer 32b, the lift is lifted. The cylinder 20 is stopped in its operating state. At this time, the control means 40 increases the difference between the height detected by the connection height sensor 37 and the control target descending position as the lift cylinder 20 increases.
In the state in which the control target speed of No. 3 becomes large, and the control characteristic selected by the characteristic changing unit 34, that is, FIG.
As shown in (b), the lift cylinder 20 is operated with the control characteristic selected from the ones in which the maximum speed of the control target speed of the lift cylinder 20 set corresponding to the deviation is different. As a result, the rotary tiller 10 is lowered to the connecting height lowered by the stroke corresponding to the operation stroke of the position lever 32a, and is lowered at a higher speed as it is farther from the control target lowering position as shown in FIG. Then, as it approaches the control target lowering position, it descends at a lower speed to reach the control target lowering position.

[Other Embodiments] As the control switching means 33, the characteristic changing means 34, and the plowing depth setting means 36, switches and potentiometers are adopted as in the above embodiment, and a touch panel using liquid crystal is adopted. You may carry out.

The present invention can be applied to a work vehicle in which various working devices other than a rotary cultivator are connected to a self-propelled vehicle in addition to a cultivator. These cultivators and various work vehicles are collectively referred to. The working machine is called, the rotary tilling device 10 and the like are collectively called the ground working device 10, and the working depth sensor 38 is called the working depth sensor 38.

[Brief description of drawings]

1] Side view of the entire riding-type cultivator

FIG. 2 is a block diagram of a control device.

[Fig. 3] Hydraulic circuit diagram

4A is an explanatory diagram of a detection height by a connection height sensor, FIG. 4B is an explanatory diagram of a conventional control characteristic, and FIG.
Explanatory drawing of control characteristics of the present invention

5A is an explanatory diagram of a detection height by a connection height sensor, and FIG. 5B is an explanatory diagram of a control characteristic of the present invention.

FIG. 6 is a control flow diagram.

[Fig. 7] Flow chart of lifting control

FIG. 8: Flow diagram of automatic plowing depth control

FIG. 9: Flow chart of position control

[Explanation of symbols]

10 Ground work device 20 hydraulic actuator 31 Down command means 32 Second descending command means 33 Control switching means 34 Characteristic changing means 37 Connection height sensor 38 Working depth sensor 40 control means

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Claims (3)

[Claims] 1. A ground actuator based on a detection result of the hydraulic actuator for lifting and lowering the ground work device with respect to a self-propelled vehicle body, a work depth sensor for detecting the work depth of the ground work device, and the work depth sensor. A control device for a working machine, comprising a control means for performing a working depth control for operating the hydraulic actuator so that the working depth of the device becomes a set working depth, the lowering operation of the ground working device is performed. Descending command means for commanding,
And a connection height sensor for detecting a connection height of the ground work device with respect to the self-propelled vehicle body, and the control means, when instructed by the descending command means, determines that the work depth of the ground work device is the set work depth. Based on the deviation between the height detected by the connection height sensor and the set work depth, the control target speed is set in a state where the larger the deviation is, the larger the control target speed of the hydraulic actuator is, A control device for a work machine configured to execute a descent control for operating a hydraulic actuator on the work device descent side at the control target speed. 2. The control means is provided with a characteristic changing means for giving a control characteristic changing command to the control means so as to adjust and set the control target speed with respect to the deviation. Control device for work equipment. 3. A second descending command means for commanding a descending operation of the ground work apparatus and a control target descending position, and a control switching means for switching the control means between an automatic control mode and a manual control mode. When the means is switched to the automatic control mode,
When the working depth control and the descending control are executed and the mode is switched to the manual control mode, this deviation is based on the deviation between the detected height by the connecting height sensor and the control target descending position by the second descending command means. The control target speed is set in a state in which the larger the control target speed of the hydraulic actuator becomes, the hydraulic actuator is moved to the work device lowering side so that the ground work device is at the control target lowering position. The second lowering control which is operated in accordance with (1) is executed, and the maximum speed of the control target speed to be set is changed based on a control characteristic change command from the characteristic changing means. Control device for the work machine described.