JPH10309106A - Working machine controlling mechanism for tractor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a working machine controlling mechanism that can be fully constituted by an electric circuit, by using a rack position sensor of an electronic governor attached to an engine also as a load factor detecting sensor and controlling so as to make the load of the engine in a fixed set range against the change of load on a working machine. SOLUTION: An engine to be loaded on a tractor is equipped with an electronic governor mechanism A consisting of a sensor 1 for detecting the number of revolutions, a rack position sensor 2, a rack actuator 9 and an electron controlling part G. The rack position sensor 2 is used as a load factor sensor and the load of the engine is controlled in a fixed set range agents the change of load on a working machine of a tractor. The working state and nonworking state of the working machine is judged and the traveling condition can be controlled by installing the electric governor A and a load factor setting device 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work machine control mechanism such as a rotary tilling device mounted on a tractor.

[0002]

2. Description of the Related Art A conventional tractor work machine control mechanism is constructed as described in Japanese Patent Application Laid-Open No. 58-20524. That is, the draft sensor rod biased by spring is pressed by the pressing force applied to the top link portion of the three-point link type working machine mounting device, and the draft sensor rod mechanically moves the hydraulic valve for lifting and lowering the working machine. Thus, when the traction force is large, the work machine is raised, and when the traction force is small, the work machine is lowered to control the draft force to be constant.

[0003]

SUMMARY OF THE INVENTION The present invention determines the working state and non-working state of a working machine, and in the working state, travels at an engine speed fluctuating at a constant load factor along a map d of droop control. Then, in the non-working state, the vehicle is controlled to run at a constant load and fluctuating load factor along the map i of the isochronous control. In addition, as in the prior art, the sensor rod is mechanically moved, and the feedback is not performed mechanically, but the detection is performed electronically by an electronic governor mechanism, and a work implement elevating valve configured by an electromagnetic switching valve, The other feedback mechanisms were also configured to be switched. As a result, the mechanical sensor rod conventionally configured mechanically can be eliminated,
The work machine control mechanism of all tractors can be constituted by an electronic circuit.

[0004]

The problems to be solved by the present invention are as described above. Next, means for solving the problems will be described. According to the first aspect, an engine mounted on a tractor is provided with an electronic governor mechanism A including a rotation speed detection sensor 1, a rack position sensor 2, a rack actuator 9, and an electronic control unit G, and a rack position of the electronic governor mechanism A is provided. The sensor 2 is also used as a load ratio detection sensor, and controls the engine load to be within a certain set range with respect to a change in the load applied to the work implement of the tractor.

According to a second aspect of the present invention, a rotational speed detecting sensor 1 is provided.
An electronic governor mechanism A including a rack position sensor 2, a rack actuator 9, and an electronic control unit G, and a load factor setting device 6 for setting a set load factor F. In the working state, the engine runs at a constant load factor and fluctuates along the map d of the droop control, and in the non-working state, fluctuates at a constant speed along the map i of the isochronous control. The control is performed so that the vehicle runs at a load factor.

According to a third aspect of the present invention, the rotational speed detecting sensor 1
An electronic governor mechanism A including a rack position sensor 2, a rack actuator 9, and an electronic control unit G; and a load factor setting unit 6 for setting a set load factor F. The electronic control unit G of the electronic governor mechanism A is provided. The detection load factor FS
And by comparing the load factor setting device 6 with the detected load factor FS, the tilling cover 21 of the rotary tilling device R is rotated back and forth.

According to a fourth aspect, the rotation speed detecting sensor 1
An electronic governor mechanism A including a rack position sensor 2, a rack actuator 9, and an electronic control unit G; a load factor setting device 6 for setting a set load factor F; a lift elevating solenoid valve V1, V2; A draft that includes the angle sensor 3 and that controls the lifting and lowering of the working machine so that the detected load factor FS detected by the electronic control unit G in the working state falls within the set range of the set load factor F set by the load factor setting device 6. In the control mechanism, the draft sensor is shared by the rack position sensor 2.

[0008]

Next, embodiments of the present invention will be described.
1 is a side view of a tractor equipped with a rotary tilling device as a working machine, FIG. 2 is a side sectional view of an electronic governor mechanism A,
3 is a side view of the electronic governor mechanism A, FIG. 4 is a drawing showing an example of a control map by the electronic governor mechanism A, and FIG. 5 is a hydraulic circuit diagram of a working machine lifting mechanism B having lift lifting / lowering solenoid valves V1 and V2. It is.

Referring to FIG. 1, the structure of the tractor will be described. An engine E is disposed inside the hood of the tractor, and an electronic governor mechanism A is attached to a side surface of the engine E. An accelerator lever 14 for setting the number of revolutions of the engine E by an operator is rotatably supported by a dashboard portion of the hood, and an accelerator lever sensor 5 is disposed at a base of the accelerator lever 14. The accelerator lever sensor 5 detects how much the operator has turned the accelerator lever 14 and how much rotation speed the operator desires to set. A work implement control panel 15 is provided beside the tractor seat.
5, an automatic / manual changeover switch 8 for switching between automatic control and manual control of the working machine, a load factor setting device 6 for setting the load factor of the working machine, and setting the position of the working machine during position control. A work implement position setting device 7 is provided. In addition, the rotary tiller R mounted on the rear of the tractor is provided with a tillage depth sensor 4 for detecting the tillage depth during the depth control of the working machine. The rear cover 22 is configured to be rotatable back and forth. Further, a lift angle sensor 3 is arranged at the base of the lift arm 13 for position control.

2 and 3, an electronic governor mechanism A
Will be described. The electronic governor mechanism A is an engine E
The magnetic rotating body 12 is fixed to a cam shaft 16 of the fuel pump. The rotation of the camshaft 16 is detected by the rotation speed detection sensor 1 of the magnetic rotator 12 to obtain the engine rotation speed. Further, the fuel supply amount of the electronic governor mechanism A is adjusted by moving the fuel rack 10 to the left and right.
Is driven by the rack actuator 9. Also,
The fuel rack 1 moved by the rack actuator 9
The rack position sensor 2 detects the position of “0” and detects the fuel supply amount. A rack bar 11 connected to a fuel rack 10 is inserted through the rack position sensor 2 and the rack actuator 9. In claim 2 of the present invention, the rack position sensor 2 is also used as a draft sensor.

Next, referring to FIG. 4, a control curve of the engine E by the electronic governor mechanism A will be described. In the engine E, the engine output and the shaft torque are determined by the injection amount and the injection timing of the fuel injection pump and the engine speed. The fuel injection amount is adjusted by sliding the fuel rack 10 by the rack actuator 9. And it is obtained by measuring the injection amount based on the position of the fuel rack 10 and the engine speed. The injection timing is adjusted by a timing adjustment actuator (not shown). The engine speed is detected by a speed detection sensor 1. Accelerator lever 1 for operator in electronic control unit G
By rotating the rotation 4, an instruction of the number of rotations is issued via the accelerator lever sensor 5. As the electronic control unit G, a microcomputer is used, and a program ROM storing a control program is arranged. In addition, a data ROM storing various data required for control calculation such as speed fluctuation rate characteristics is arranged.

In the data rom, what is the set value of the engine speed arbitrarily set according to the position of the accelerator lever 14 operated by the operator by himself / herself and the actual speed (actual value) according to the load. Such a speed variation characteristic is stored in the form of an arithmetic expression or a numerical table for each different work content. Regarding the speed fluctuation rate, the set value and the actual value of the period rotation speed are recognized, then the mode set by the operator is recognized, and the target rack position to be set is calculated by the droop rate map according to the mode. . A signal for changing the actual rack position to the corrected target rack position is output to the rack actuator 9, the fuel rack 10 is automatically adjusted, and the operation is performed within a predetermined speed fluctuation range. Normally, control is performed along the map d of the droop control shown in FIG. 4 so as to recognize a predetermined speed fluctuation, the fuel rack 10 changes, and the shaft torque changes.
That is, the engine speed fluctuates up and down to keep the load factor constant.

The speed variation characteristic is selected according to the mode of the work content. When constant speed operation is required,
A constant rotation operation is performed along the map i of the isochronous control to increase or decrease the fuel consumption and to keep the engine speed constant. In addition, even in the case of isochronous control, especially in the case of special work, when the load increases and it is close to the maximum shaft torque, the reverse droop that increases the rotation speed and the shaft torque to prevent engine stall. It is also possible to select a control map r.

FIG. 5 shows a hydraulic circuit diagram of the working machine lifting mechanism B. The lift arm 13 is turned up and down by the expansion and contraction of the hydraulic cylinder 20,
Is provided with a lift angle sensor 3 for detecting the position. The lift hydraulic control valves V1 and V2 control the pressure oil to the hydraulic cylinder 20, and are constituted by a lift electromagnetic valve V1 and a downward magnetic valve V2. A signal for switching between the ascending solenoid valve V1 and the descending solenoid valve V2 is transmitted from the lift electronic control unit C.

FIG. 6 shows an electronic control unit G of the electronic governor mechanism A.
6 is a diagram illustrating movements of a detection signal and a command signal between a lift electronic control unit C and a work implement elevating mechanism B. In FIG. 6, an electronic governor mechanism A including a rotation speed detection sensor 1, a rack position sensor 2, a rack actuator 9, and an electronic control unit G, a lift elevating solenoid valve V1, V2,
It has an accelerator lever sensor 5, a load factor setting device 6, and a lift angle sensor 3, and the detected load factor FS detected by the electronic control unit G in the working state is equal to the set load factor F set by the load factor setting device 6. This is a technique for controlling the lifting and lowering of a work machine so that the working machine falls within a set range. As shown in FIG. 6, signals are communicated between the electronic control unit G and the lift electronic control unit C of the electronic governor mechanism A, and signals are also transmitted between the lift electronic control unit C and the work implement elevating mechanism B. Being communicated. The essential part of the present invention is that the signal of the electronic governor mechanism A can be used as a control signal of the work implement elevating mechanism B. That is, the electronic governor mechanism A and the work implement elevating mechanism B are connected via the lift electronic control unit C.

FIG. 7 shows the rear cover 22 and the tillable rotation cover 2 of the rotary tillage device R based on the increase and decrease of the engine load factor.
2 is a drawing showing a control mechanism before and after 1. That is, when the engine load factor detected by the rack position sensor 2 increases or decreases with respect to the set load factor F, the rotary tilling device R
Rather than moving up and down, but by moving the tillage rotation cover 21 back and forth. Since the rotary tilling device R is not moved up and down, the tilling depth is constant, and the position of the rear cover 22 only needs to rotate back and forth.

When the working machine shifts from the working state to the non-working state, the load on the working machine changes, so that the operator needs to operate the accelerator lever 14. The configuration is such that the load ratio is controlled constant in the state and the engine speed is controlled constant in the non-working state, so that the operator does not need to operate the accelerator lever 14 when changing the working state.

FIG. 8 is a control block diagram for position control, and FIG. 9 is a control block diagram for draft control. When performing position control in FIG. 8,
The rotation of the position lever 7a causes the position setting device 7 to rotate.
Is set, and the one-touch elevating switch 18 provided on the dashboard portion of the tractor allows the tractor to ascend at a stretch at the time of circling the field. In addition, the raising height by the one-touch lifting switch 18 is raised, and the height dial 18 is used.
It can be set by a. When the mode is switched by the automatic / manual switch 8 and the set height is designated by the position lever 7a or the lifting height dial 18a, the lift lifting / lowering solenoid valves V1 and V2 are switched, and the lift arm 13 rotates up and down. The lift angle sensor 3 detects the rotation angle. Then, the working machine is made to converge to the set height.

Next, the case of the draft control will be described. In this case, the set load factor F is set by the load factor setting device 6. Then, the set load factor F is substantially equal to the detected load factor FS detected by the rack position sensor 2,
The switching control of the lift lifting / lowering solenoid valves V1 and V2 is performed.
In the second aspect of the present invention, the main part is that the draft control sensor is changed from a conventional mechanical sensor to the rack position sensor 2 and detected as an electronic signal.

During the tillage operation by the rotary tillage device, even if the load factor of the engine fluctuates, the lift elevating solenoid valves V1 and V2 are not moved, and the tillage depth remains constant. Then, instead of raising and lowering the cultivation depth, the tilling rotation cover 21 and the rear cover 22 are rotated back and forth to change the tilling load factor on the tilling claw, thereby increasing or decreasing the engine load factor.

FIG. 10 is a control block diagram showing constant load factor control and constant rotation control, FIG. 11 is a control flowchart, and FIG. 12 is a control state. The switching point between the working state and the non-working state may be determined by the lift angle sensor 3 or may be determined based on the magnitude of the load factor. Based on the detection by the work / non-work detector 23, a control command is issued to the electronic governor mechanism A to perform constant load factor control for draft control in the work state, and to reduce the load in the non-work state. Therefore, if the load factor is fixed, the rotational speed abnormally increases, and the load factor may fluctuate. Therefore, the control is changed so that the rotational speed is constant. FIG. 11 shows a flowchart of the constant load factor control and the constant rotation speed control after the determination by the work / non-work detector 23. FIG. 12 shows a state in which the constant number of revolutions during the non-operation changes. That is, in a non-working state in an upper position where the working machine is not in contact with the ground, the engine speed is controlled to a constant speed at a low position, and when the rotary tilling device R is lowered, the position is set at a position close to the ground. It is configured to set the rotation speed to a high rotation speed.

In the conventional draft control mechanism, the hydraulic switching valve is controlled by a mechanical sensor mechanism provided at the top link and a feedback mechanism formed by a link and an arm. In the case of, the detection of the detected load factor FS is also used by the rack position sensor 2 of the electronic governor mechanism A, the load factor is set by the load factor setting device 6, and all signals are obtained as electronic signals, and the draft control is performed. Is made possible. Originally, the electronic governor mechanism A is an electronic control mechanism for automatically controlling the number of revolutions and the load factor of the engine E and the fuel supply amount. The present invention uses the electronic governor mechanism A as a control component for draft control. By using it as a part, a draft control with a simple structure and all of it was made electronic.

FIG. 13 shows that the plowing depth position sensor 4 provided on the rear cover 22 is also a depth sensor, and the rack position sensor 2 detects the engine load ratio as a draft sensor.
A control block diagram for controlling V2 is disclosed. Although both sensors are used in combination, usually, the priority is given to moving the working machine up and down based on the detection value of the tillage depth position sensor 4 and, when the load of the engine E increases, the detection value of the tillage depth position sensor 4 is increased. Irrespective of this, it is configured to control the lift lifting / lowering solenoid valves V1 and V2 so that the set load factor is achieved. When the load factor decreases, the control by the tillage depth position sensor 4 is switched. Further, the draft control is activated by the load of the engine, and when the number of times of lifting and lowering of the work implement becomes equal to or more than a certain number within a certain time, a display is provided by an overload indicator.

FIG. 14 is a drawing showing control for controlling the speed when the work machine is installed on the ground.
In this case, such as at the end of the field, the engine load gradually becomes the set load factor F after the lowering operation of the work implement,
It controls the lowering speed of the work machine. Thus, it is possible to prevent the sudden load fluctuation of the engine E from occurring when the work machine is lowered.

FIG. 15 is a flowchart in the case where the vehicle speed of the tractor is simultaneously controlled by the electronic governor mechanism A, and FIG. 16 is also a control block diagram. In this configuration, the speed is set by the speed setting device 25, the rotation speed range is set by the engine rotation speed range setting device 26, and the engine rotation speed is set in the rotation speed range. Then, the speed is detected by the speed sensor 24, an instruction is issued to the electronic governor mechanism A by comparing the two, and the fuel rack 10 moves so that the engine speed and the speed always become the same. When the vehicle speed comes out of the range set by the engine speed range setting device 26, an alarm is issued to the operator. By providing the engine speed range setting device 26 in this manner, the engine speed becomes higher and the PTO speed does not become higher. If the set speed cannot be obtained within the set speed range,
The operator changes gears.

FIG. 17 is a flowchart in the case of controlling the slip ratio in addition to the control of the vehicle speed, and FIG. 18 is a control block diagram similarly. In this technique, an axle rotation speed sensor 28 and a limit slip rate setting device 27 are provided,
A vehicle speed detected by the speed sensor 24 by detecting a slip ratio from the axle speed sensor 28 and the speed setting device 25;
The engine speed is calculated from the calculated slip rate, and the electronic governor mechanism A is instructed. When the slip rate exceeds the slip rate set by the limit slip rate setting device 27, an alarm is issued to the operator.

[0027]

As described above, the present invention has the following advantages. The engine mounted on the tractor is provided with a rotational speed detection sensor 1, a rack position sensor 2, a rack actuator 9, and an electronic control unit G.
And the rack position sensor 2 of the electronic governor mechanism A is also used as a load factor detection sensor, so that the engine load is set to a constant value with respect to a change in the load applied to the work machine of the tractor. By controlling the load to be within the range, the load applied to the engine can be kept constant with respect to the change in the load applied to the work equipment, so if the load applied to the work equipment is small, Speed up the rotation, increase the tractor's running speed, and if the load on the work equipment is large, slow down the engine rotation and slow down the tractor's running speed to make the working speed more efficient. Work time can be shortened.

According to a second aspect of the present invention, the working state of the working machine and the non-working state are determined. In the working state, the vehicle travels at a constant load factor and fluctuates according to the droop control map d. Eliminates the need for accelerator lever operation caused by changes in work and non-work conditions by controlling to run with a constant load and fluctuating load rate in accordance with the isochronous control map i in the state. I was able to get the job done smoothly. Especially when turning, it is necessary to operate the steering wheel, and there is no room to operate the accelerator lever 14, but by configuring as in the present invention, it is not necessary to operate the accelerator lever 14, so that the safety of the operator is reduced. You can do it.

According to the third aspect, the rotational speed detection sensor 1
An electronic governor mechanism A including a rack position sensor 2, a rack actuator 9, and an electronic control unit G; and a load factor setting unit 6 for setting a set load factor F. The electronic control unit G of the electronic governor mechanism A is provided. The detection load factor FS
Is detected, and the load ratio setting device 6 is compared with the detected load ratio FS, so that the tilling rotation cover 21 of the rotary tilling device R is configured to rotate back and forth, so that the following effects are obtained. Things. That is, when the load factor is increased or decreased, it is possible to return to the set load factor F by first rotating the portion of the tilling rotation cover 21 and the rear cover 22 back and forth without raising and lowering the work implement. The plowing depth can be kept constant. Further, since the change in the load factor can be detected as an electric signal by the electronic governor mechanism A, it is not necessary to provide a separate draft sensor.

Further, according to the present invention, the rotation speed detecting sensor 1
An electronic governor mechanism A including a rack position sensor 2, a rack actuator 9, and an electronic control unit G; a load factor setting device 6 for setting a set load factor F; a lift elevating solenoid valve V1, V2; A draft that includes the angle sensor 3 and that controls the lifting and lowering of the working machine so that the detected load factor FS detected by the electronic control unit G in the working state falls within the set range of the set load factor F set by the load factor setting device 6. In the control mechanism, since the draft sensor is also used by the rack position sensor 2, the following effects can be obtained. That is, unlike the related art, there is no need to provide a mechanical and complicated draft sensor mechanism as in the related art, and since the rack position sensor 2 of the electronic governor mechanism A is also used, the wear resistance and durability are improved. In addition, since it is not necessary to provide a sensor or a feedback mechanism at the base of the hydraulic lift arm, the structure of the draft control mechanism can be simply configured.

[Brief description of the drawings]

FIG. 1 is a side view of a tractor equipped with a rotary tilling device as a working machine.

FIG. 2 is a side sectional view of the electronic governor mechanism A.

FIG. 3 is a side view of the electronic governor mechanism A.

FIG. 4 is a diagram showing an example of a control map by an electronic governor mechanism A.

FIG. 5 is a hydraulic circuit diagram of a working machine elevating mechanism B including lift elevating electromagnetic valves V1 and V2.

FIG. 6 is a diagram illustrating the movement of a detection signal and a command signal among an electronic control unit G, a lift electronic control unit C, and a work implement elevating mechanism B of the electronic governor mechanism A.

FIG. 7 is a drawing showing a control mechanism for moving a rear cover 22 and a tillage rotation cover 21 of a rotary tillage device R back and forth based on an increase and a decrease in an engine load factor.

FIG. 8 is a control block diagram in the case of position control.

FIG. 9 is a control block diagram in the case of draft control.

FIG. 10 is a control block diagram showing constant load factor control and constant rotation control.

FIG. 11 is a control flowchart drawing.

FIG. 12 is a drawing showing a control state.

FIG. 13 shows that the tillage depth position sensor 4 provided on the rear cover 22 is also a depth sensor, and the rack position sensor 2
FIG. 5 is a control block diagram in a case where a draft sensor is detected by detecting an engine load factor, and both are used as sensors to control the lift elevating electromagnetic valves V1 and V2.

FIG. 14 is a diagram showing control for controlling speed when the work machine is installed on the ground.

FIG. 15 is a flowchart in the case where the electronic governor mechanism A simultaneously controls the vehicle speed of the tractor.

FIG. 16 is a control block diagram.

FIG. 17 is a flowchart in a case where control of a slip ratio is performed in addition to control of a vehicle speed.

FIG. 18 is also a control block diagram.

[Explanation of symbols]

 F Set load factor FS Detected load factor D Detected towing load DM Average calculated value A Electronic governor mechanism B Work implement elevating mechanism C Lift electronic control unit V1 Elevating solenoid valve V2 Descending solenoid valve 1 Rotation speed detection sensor 2 Rack position sensor 3 Lift angle Sensor 4 Tillage depth sensor 5 Accelerator lever sensor 6 Load factor setting device 7 Work implement position setting device 8 Automatic / manual switch 9 Rack actuator 10 Fuel rack 11 Rack bar 12 Magnetic rotating body 18 PTO connecting / disconnecting solenoid valve 19 Ground work Machine load detector 20 Hydraulic cylinder 21 Tilling rotation cover 22 Rear cover 23 Work / non-work detector 24 Speed sensor 25 Speed setting device 26 Engine speed range setting device 27 Limit slip ratio setting device 28 Axle speed sensor

Continued on the front page (72) Inventor Kiyohide Yoshikawa 1-32 Chaya-cho, Kita-ku, Osaka City, Osaka Inside Yanmar Diesel Co., Ltd.

Claims (4)

[Claims] An engine mounted on a tractor is provided with an electronic governor mechanism A including a rotation speed detection sensor 1, a rack position sensor 2, a rack actuator 9, and an electronic control unit G, and a rack position sensor of the electronic governor mechanism A is provided. 2
And a load factor detection sensor, and controls the engine load to be within a certain set range with respect to a change in the load applied to the tractor working machine. 2. An electronic governor mechanism A comprising a rotation speed detection sensor 1, a rack position sensor 2, a rack actuator 9, and an electronic control unit G, and a load factor setting device 6 for setting a set load factor F are provided. The working state and non-working state of the work machine are determined. In the working state, the vehicle runs at a constant load factor and fluctuating engine speed along the droop control map d. A tractor working machine control mechanism for controlling the vehicle to run at a constant load and fluctuating load factor. 3. An electronic governor mechanism A including a rotation speed detection sensor 1, a rack position sensor 2, a rack actuator 9, and an electronic control unit G, and a load factor setting device 6 for setting a set load factor F are provided. The detected load factor FS is detected by the electronic control unit G of the electronic governor mechanism A, and the load factor setting device 6 is compared with the detected load factor FS so that the tilling rotation cover 21 of the rotary tilling device R can be moved forward and backward. A work machine control mechanism for a tractor, wherein the mechanism is configured to rotate. 4. An electronic governor mechanism A comprising a rotation speed detection sensor 1, a rack position sensor 2, a rack actuator 9, and an electronic control unit G, and a load factor setting device 6 for setting a set load factor F are provided. Lift lift solenoid valve V1 ・
V2 and the lift angle sensor 3, and the work machine is set so that the detected load factor FS detected by the electronic control unit G in the working state falls within the setting range of the set load factor F set by the load factor setter 6. In a draft control mechanism that controls lifting and lowering,
A work implement control mechanism for a tractor, wherein the draft sensor is also used by the rack position sensor 2.