JPH0610972A - Mechanical disengaging device for hydraulic main clutch - Google Patents

Abstract

PURPOSE:To stop a vehicle via an action other than the action of a solenoid proportional valve by providing a mechanical valve stopping the feed of the pressure oil to disengage a clutch via the depression of a clutch pedal and draining the pressure oil in the hydraulic main clutch at the final position of the depression. CONSTITUTION:When a clutch pedal 2 is depressed, an angle detecting sensor 10 detects the depression quantity as the angle change, and a controller 11 operates a solenoid proportional valve 3 in the closing direction with the signal. When the output voltage of the controller 11 is changed, the opened degree of the solenoid proportional valve 3 is changed, the pressure oil quantity to a hydraulic clutch 4 is squeezed, and the clutch 4 is disengaged. When the clutch pedal 2 is depressed to the position of the two-dot chain line at the depression final position, an operating member 12 sways a swaying member 13, a mechanical valve 5 is switched via a Bowden wire 14, the feed of the pressure oil to the hydraulic main clutch 4 is stopped, and the pressure oil in the hydraulic main clutch 4 is drained. A piston is retreated, and the clutch 4 is disengaged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanical disengagement device for a hydraulic main clutch used in a traveling vehicle which uses a hydraulic clutch as a main clutch of a traveling power transmission system.

[0002]

2. Description of the Related Art For example, in a traveling vehicle such as a tractor, a hydraulic transmission may be used as a transmission of a traveling power transmission system. In that case, a dry main clutch is omitted and a wet hydraulic clutch of the hydraulic transmission is used. It is considered to give the main clutch the function.

The hydraulic clutch of the hydraulic transmission having such a function, that is, the hydraulic main clutch is adapted to be opened / closed by opening / closing an electromagnetic proportional valve in response to depression / release of the clutch pedal. It is also possible to obtain a half-clutch state.

[0004]

The solenoid proportional valve is designed to detect the depression amount (including the opening amount) of the clutch pedal by an angle detection sensor and control the opening / closing degree via a controller by the signal. If the electric circuit fails for some reason, such as a short circuit, the solenoid proportional valve may stop in the open or closed state.

When the solenoid proportional valve is stopped in the closed state, the pressure oil in the hydraulic main clutch is drained through the solenoid proportional valve, so that power transmission can be cut off. However, when the vehicle is stopped in the open state, it is necessary to disengage the clutch of the main switch or the other transmission of the traveling power transmission system, and another operation other than the clutch pedal operation is required, which complicates the processing.

According to the present invention, the hydraulic oil supply circuit of the hydraulic main clutch is provided with a mechanical valve which operates at the final position of depression of the clutch pedal to drain the hydraulic oil, thereby making it possible to solve the above-mentioned problems. An object of the present invention is to provide a mechanical cutting device for a main clutch.

[0007]

The concrete means for solving the problem in the present invention is to close the electromagnetic proportional valve 3 in response to the depression of the clutch pedal 2 and turn off the hydraulic pressure by stopping the pressure oil supply. In the main clutch, a mechanical valve 5 is provided which operates at the final position of depression of the clutch pedal 2 to drain the pressure oil in the hydraulic main clutch 4.

[0008]

When the clutch pedal 2 is stepped on, the angle detection sensor 10 operates to send a signal corresponding to the stepped amount to the controller 11, which throttles the solenoid proportional valve 3 to the hydraulic main clutch 4. Reduce the amount of pressure oil supply and start the cutting operation.

When the clutch pedal 2 is depressed to the final position, the mechanical valve 5 operates to stop the pressure oil supply to the hydraulic main clutch 4 and drain the pressure oil inside the hydraulic main clutch 4 to disengage the hydraulic main clutch 4. Put in a state.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. In the first embodiment shown in FIGS. 1 to 3, 1 is a mechanical disengaging device for a hydraulic main clutch applied to a tractor as a traveling vehicle, 2 is a clutch pedal, 3 is an electromagnetic proportional valve, 4 is a hydraulic main clutch, 5 Indicate mechanical valves, respectively.

The hydraulic main clutch 4 is a switching hydraulic clutch such as a high / low transmission and a forward / reverse switching device for a traveling power transmission system of a tractor transmission, and pressure oil can be supplied from a pump 8. The clutch pedal 2 is pivotally supported by a support base of the tractor control section via a support shaft 9.
The depression amount of the clutch pedal 2 is detected by the angle detection sensor 10, and the detection signal is the controller 1
Sent to 1. Although the angle detection sensor 10 is provided separately from the clutch pedal 2, it may be provided on the support shaft 9.

The controller 11 is connected to the solenoid proportional valve 3, changes the output voltage according to the detection signal obtained from the angle detection sensor 10, and closes the solenoid proportional valve 3 from the open state in response to the depression of the clutch pedal 2. It is designed to change to a state. The solenoid proportional valve 3 is in an open state when it is not excited and supplies pressure oil to the hydraulic main clutch 4.
When excited, the amount of throttled pressure oil is changed, and finally the closed state is reached so that the pressure oil can be drained from the hydraulic main clutch 4.

The clutch pedal 2 is provided with an operating member 12 which is integrally rotatable. This operating member 12 is
When the clutch pedal 2 is stepped on to the final position, the rocking member 13 is rocked together. The swinging member 13 is pivotally supported on a support base, and a Bowden wire (transmission means) 14 for operating the mechanical valve 5 is connected thereto.

As the mechanical valve 5, a so-called manual opening / closing valve can be used,
Two positions can be switched between an open state in which pressure oil is supplied and a closed state in which pressure oil from the solenoid proportional valve 3 side is drained. Normally, in the open state, the rocking member 13 rocks and the Bowden wire 1
When 4 is pulled, it is closed. In FIG. 1, when the clutch pedal 2 is stepped on in the direction of the arrow, the angle detection sensor 10 operates to detect the stepped amount as an angle change, and the controller 11 excites the solenoid proportional valve 3 by the detection signal. The solenoid proportional valve 3 is operated in the closing direction.

When the output voltage of the controller 11 changes, the opening / closing degree of the solenoid proportional valve 3 changes, and the hydraulic main clutch 4
The amount of pressure oil supplied to is reduced to the clutch disengaged state from the clutch engaged state to the half clutch state (shown by the dotted line in FIG. 2). When the clutch pedal 2 is depressed to the position indicated by the chain double-dashed line in FIG. 1, the final position of depression is reached. At that time, the operating member 12 swings the swinging member 13 to switch the mechanical valve 5 via the Bowden wire 14 to switch the hydraulic main clutch. The pressure oil supply to the hydraulic pressure main clutch 4 is stopped, and the pressure oil in the hydraulic main clutch 4 is drained. When the hydraulic oil is drained from the hydraulic main clutch 4, the piston pressing the clutch plate retracts and enters the clutch disengaged state (shown by the solid line in FIG. 2).

A cam groove 17 is formed in the actuating member 12, and a pin 18 is inserted into the cam groove 17 so that the pin 1
8, a spring 19 for returning the clutch pedal 2 is hooked. The cam groove 17 is formed from the tip of the actuating member 12 to the vicinity of the base, and is bent in a substantially V shape. The pin 18 is movable in the cam groove 17, and the spring 1
The return force of 9 acting on the clutch pedal 2 is large when the pin 18 is located on the tip side of the cam groove 17 and is small when the pin 18 is located on the base side, and the rate of change of the return force at the bending point of the cam groove 17 is small. Change.

That is, when the pin 18 is connected to the actuating member 12 at a fixed point, the position of the clutch pedal 2 from when the clutch is engaged (ON) to when the clutch is disengaged (OFF), as shown by a chain double-dashed line in FIG. And pedal load are directly proportional,
When the pin 18 is made to move in the cam groove 17, as shown in FIG.
As shown by the solid line, the pedal load suddenly becomes heavy in the initial stage of depression, and the rate of change from the bending point to the increase in load becomes small.

If the half-clutch position of the hydraulic main clutch is set so that the half-clutch state is set near the bending point, the pedal feeling of the half-clutch can be obtained. This is particularly because when the clutch is electrically connected and disconnected like the hydraulic main clutch 4, the clutch pedal 2 does not have a half-clutch feeling like a dry mechanical main clutch, and the operation becomes difficult. In order to solve the problem, the returning force of the spring 19 is changed on the clutch pedal 2.

In the second embodiment shown in FIGS. 4 to 6, a forward / reverse switching device is illustrated here, and an electromagnetic proportional valve 3 is connected to each of the pair of hydraulic main clutches 4. The controller 11 includes forward / backward switching operation means (not shown) for selectively operating the pair of solenoid proportional valves 3.
Are connected. The clutch pedal 2 is pivotally supported on a support base 21 via a support shaft 9, and is also connected via a link 23 to an oscillating body 22 which is also pivotally supported on the support base 21.
Tension spring 19 (1st spring) between 1 and
Is stretched.

An arm 24 is integrally provided on the clutch pedal 2, one end of an inner wire 14A of the Bowden wire 14 is connected to the arm 24, and the other end is connected to a swing arm 26 via a connecting tool 25. There is. One end of the outer wire of the Bowden wire 14 is attached to the support base 21, and the other end is attached to a bracket 27 fixed to a mission case or the like, and a compression spring 28 (second portion) is provided between the bracket 27 and the connector 25. Spring) is provided.

Reference numeral 29 denotes a hydraulic body fixed to a mission case or the like, which incorporates the solenoid proportional valve 3, the mechanical valve 5 and the like. A support plate 30 and a bracket 31 are attached to the hydraulic body 29, and the support plate 30 is provided. To the swing arm 2
6 are pivoted. The swing arm 26 has a long hole 26.
a is formed, and the tip of the connecting tool 25 is connected via a pin 25a that is movably inserted into the long hole 26a. A tension spring 32 (third spring) is hung between the tip of the swing arm 26 and the bracket 31.

The pulling spring 32 is pulled when the swinging arm 26 swings, and the return force for the connecting tool 25 gradually increases.
Moves in the long hole 26a and the distance from the pivot point of the swing arm 26 increases, so that the returning force to the connecting tool 25 gradually decreases. The hydraulic body 29 has a guide 3
4 is provided and the rod 35 is slidably guided. One end of the rod 35 is connected to the connector 25, and a compression spring 36 is provided between the connector 25 and the guide 34.
(Fourth spring) is provided. The other end of the rod 35 is connected to a spool 38 of the mechanical valve 5 via a connecting body 37.

In the mechanical valve 5, the spool 38 is urged to the circuit communication position, and the pressure oil from the pump 8 is transferred to the solenoid proportional valve 3.
Can be supplied to the side. A drain hole 40 is formed at the tip of the spool 38, and when it moves in the direction of the arrow 41, it finally communicates with the drain passage 42 formed in the hydraulic body 29 and discharges the oil on the pump 8 side and the solenoid proportional valve 3 side. It is possible.

The links 22 and 23 and the spring 19
Thus, with respect to the depression of the clutch pedal 2, the first depression resistance imparting means α that applies a returning spring force that gradually decreases from the initial stage to the middle period and a gradually increasing assisting spring force from the middle period to the latter period.
Is configured. According to the first depression resistance imparting means α, the clutch pedal 2 exerts a returning force in the first half of depression and an assisting force in the latter half of depression. That is, the pedaling force for stepping on the clutch pedal 2 is maximum at the initial stage and gradually decreases to become negative, and the tension spring 19 moves the clutch pedal 2 in the stepping direction from the latter half.

The compression spring 28 applies a returning spring force, that is, a stepping resistance, which gradually increases from the latter half of the initial stepping down of the clutch pedal 2, that is, a second stepping resistance applying means for the stepping of the clutch pedal 2. It constitutes β. By the tension spring 32 and the swing arm 26 having the elongated hole 26a, the return spring force, that is, the stepping resistance, which acts from the initial stepping on of the clutch pedal 2 to gradually increase, becomes maximum in the middle period, and then gradually decreases. A third stepping resistance applying means γ is provided for the depression of the clutch pedal 2.

The third stepping resistance imparting means γ has the first and second steps until the clutch pedal 2 reaches the clutch disengaged position.
A resistance greater than the depression resistance applying means α and β is applied. The compression springs 36 and 39 act by further depressing the clutch pedal 2 from the clutch disengaged position, and when the mechanical valve 5 is in the drain state, the clutch pedal 2 has a greater depression resistance to the clutch disengaged position. Can be given.

In FIG. 4, when the clutch pedal 2 is stepped on in the direction of the arrow, the angle detection sensor 10 operates to detect the stepped amount as an angle change, and the controller 11 uses the detection signal to detect one of the solenoid proportional valves 3. Is excited to operate the solenoid proportional valve 3 in the direction to close it. When the output voltage of the controller 11 changes, the opening / closing degree of the solenoid proportional valve 3 is changed, the amount of pressure oil supplied to the hydraulic main clutch 4 is reduced, and the clutch engaged state is changed to the half clutch state to the clutch disengaged state. During normal operation, the switching operation means is operated in this state to switch the operation of the solenoid proportional valve 3 from one to the other.

The clutch pedal 2 moves the spool 38 in the direction of arrow 41 during the entire stroke, and when it reaches the final stroke position, the drain hole 40 formed at the tip communicates with the drain passage 42 formed in the hydraulic body 29. Both the oil passage on the pump 8 side and the oil passage on the solenoid proportional valve 3 side communicate with the drain passage 42 to discharge the pressure oil, and drain the pressure oil in the hydraulic main clutch 4.

The fourth and fifth springs 36, 39 act from before the spool 38 reaches the final stepping position, and it is possible to detect that the clutch pedal 2 is in the final stepping step due to the compression resistance of these springs. Then, although the final stroke cannot be entered, when the electromagnetic proportional valve 3 becomes defective, the mechanical valve 5 is operated by depressing the clutch pedal 2 to the final position.

The resistance applied to the clutch pedal 2 by the pedaling resistance applying means α, β, γ and the springs 36, 39 can be calculated as the pedaling force for pressing the clutch pedal 2. That is, as shown in FIG. 6, while the clutch pedal 2 is stepped on and rotated about 0 to 30 °, the pedaling force for the first stepping resistance imparting means α changes from plus to minus at about 15 °. However, the pedaling force for the second pedaling resistance imparting means β greatly increases from about 7 ° to 30 °,
The pedal effort for the third stepping resistance imparting means γ increases from 0 ° and then starts to decrease at about 15 °, and the pedal effort for the fourth and fifth springs 36, 39 is extremely small, about 23 °.
Works only in the range of 30 °.

The depression of the clutch pedal 2 is divided into four sections, the range A having a depression angle of about 0 to 7 ° is a play range, the range B having a depression angle of about 7 to 23 ° is a half-clutch range, and thereafter. The portion C of the above is the clutch disengagement range, and the subsequent range D of the depression angle of about 23 to 30 ° is the range in which the mechanical valve 5 is operated to the drain position. It should be noted that the half clutch is substantially in the latter half of the half clutch range B.

These stepping resistance applying means α, β, γ
When the pedaling forces for the springs 36 and 39 are combined, the actual pedaling force shown by the thick solid line in FIG. 6 is obtained, and the depression of the clutch pedal 2 is performed in the play range A, the half clutch range B and the clutch disengagement range C. In the three ranges, a pedaling force that opposes a predetermined pedaling resistance in the play range A is required, and a pedaling force that is larger than the resistance of the play range A and gradually increases from the half clutch range B to the clutch disengagement range C is required. Will be done.

This is approximately equal to the pedal force for operating the dry mechanical clutch pedal (ideal pedal force), which means that the hydraulic main clutch 4 can be operated with the feeling of stepping on the clutch pedal for operating the dry clutch. The present invention is not limited to the above embodiment, but can be variously modified. For example, the mechanical valve 5 is arranged between the solenoid proportional valve 3 and the hydraulic main clutch 4, or the swing member 13 is used.
Alternatively, the mechanical valve 5 may be operated by swinging the angle detection sensor 10.

[0034]

According to the present invention described in detail above, since the mechanical valve 5 which operates at the final depression position of the clutch pedal 2 to drain the pressure oil in the hydraulic main clutch 4 is provided, the clutch pedal At the end of stepping on 2, the pressure oil in the hydraulic main clutch 4 can be drained via the mechanical valve 5, and the hydraulic main clutch 4 is disengaged to stop the traveling vehicle other than the operation of the solenoid proportional valve 3. It becomes possible to do.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a first embodiment of the present invention.

FIG. 2 is a graph showing the relationship between the pedal depression amount and the clutch operation.

FIG. 3 is a graph showing the relationship between pedal position and pedal load.

FIG. 4 is a partial cross-sectional explanatory view showing a second embodiment.

5 is a view on arrow X in FIG. 4. FIG.

FIG. 6 is a clutch pedal effort force diagram in the clutch pedal operation mechanism.

[Explanation of symbols]

 2 clutch pedal 3 solenoid proportional valve 4 hydraulic main clutch 5 mechanical valve 8 pump 10 angle detection sensor 11 controller 12 actuating member

Claims (1)

[Claims] 1. A hydraulic main clutch that is operated by closing a solenoid proportional valve (3) in response to depression of a clutch pedal (2) and stopping supply of pressure oil, the depression of the clutch pedal (2). Working in the final position,
A mechanical disengaging device for a hydraulic main clutch, comprising a mechanical valve (5) for draining pressure oil in the hydraulic main clutch (4).