JPH01156145A - Hydraulic clutch for running service car - Google Patents

Abstract

PURPOSE:To prevent the occurrence of shocks while enabling a hydraulic clutch to be quickly turned on by controlling a valve mechanism for adjusting the pressure of working oil supplied to the hydraulic clutch is a travelling system to maintain an acceleration value in the travelling system approximately at a predetermined value. CONSTITUTION:In a clutch case connected to an input shaft of a travelling system are provided a first hydraulic clutch C1 for transmitting power from the input shaft to the output gear and a second hydraulic clutch C2 for transmitting power from the input shaft 4 directly to the input gear. In oil paths 23, 24 for sending pressurized oil from a hydraulic pump 21 through a forward and backward change-over valve 22 to respective hydraulic clutches C1, C2 are provided electromagnetic proportional pressure reducing valves V1, V2. Also, a change-over switch 26 for detecting the operation position of valve 22 and a sensor S for detecting acceleration in the travelling system from the rotation of wheel are provided and a controller 25 receiving the outputs of said switch and sensor controls said valves V1, V2 to maintain the acceleration at a predetermined value and adjust pressure of oil supplied to the hydraulic clutches C1, C2.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a hydraulic clutch/notch device for driving a working vehicle,
More specifically, the present invention relates to a technique for reducing shock when engaging and operating a friction-type hydraulic clutch.

[Conventional technology]

Conventionally, as a technique for reducing the shock when engaging the hydraulic clutch as described above, there is a technique disclosed in Japanese Patent Application Laid-Open No. 62-2
There is a method disclosed in Japanese Patent No. 31841, and in this reference, the pressure of the hydraulic oil supplied to the hydraulic clutch is adjusted based on the acceleration of the traveling system when the hydraulic clutch is operated in the engaging direction. , the clutch is configured to operate the clutch without performing the engagement operation slowly and without generating a shock.

[Problem that the invention seeks to solve]

Furthermore, when a friction type hydraulic clutch is engaged, a quick supply of pressure oil is required from the start of supply of pressure oil until the friction plates begin contact and reach a half-clutch state, and after reaching a half-clutch state, It is necessary to maintain this half-clutch state for an appropriate period of time while gradually accelerating.

In addition, in the structure of the above cited example, a sensor etc. for detecting acceleration during running is attached to the vehicle body, and furthermore,
Since detection signals from sensors, etc. are fed back even when accelerating with the clutch partially engaged, for example, when fluctuations in the longitudinal posture of the vehicle affect the sensors, etc., such as when the vehicle is driving on rough ground. In this case, the pressure regulation operation is performed according to the signal from the sensor, which causes the hydraulic pressure for the clutch to pulsate, causing a shock, and also prolonging the time it takes for the clutch to reach the engaged state, so there is room for improvement. There is.

An object of the present invention is to configure a device that engages and operates a hydraulic clutch without causing as much shock as possible and without slowing down the operation, no matter what conditions the vehicle is running. .

[Means for solving problems]

The present invention is characterized by providing a friction-type hydraulic clutch installed in the running system, a valve mechanism for regulating the supply pressure of hydraulic oil to the hydraulic clutch, and a measuring means for detecting the acceleration of the running system. The acceleration of the traveling system in the acceleration direction when hydraulic oil is supplied to the vehicle is determined based on the detection signal from the measuring means, and the operation of the valve mechanism is adjusted to maintain this acceleration value at approximately a predetermined value. The feature is that a control means is provided, and its functions and effects are as follows.

[For production]

If the above characteristics are configured as shown in FIGS. 1 and 2, for example, when the hydraulic clutch (C) is operated in the on-going direction and reaches a half-clutch state, the flowchart 1 in FIG.
As shown in step #9 of ・, after the pressure increase of the hydraulic oil is once suppressed, the measurement means (S
), the pressure of the hydraulic oil for the hydraulic clutch (C) is adjusted, and as a result, the vehicle speed is increased to a desired acceleration value (steps n11 to #16).
.

That is, in this control system, the measuring means (S) linked to the running system
The system operates according to the detection results, so even if the vehicle body tilts in the front-rear direction, such as when the vehicle is driven on uneven ground, the measurement means will not detect an error.
Furthermore, after reaching the half-clutch state, the traveling speed is increased at a predetermined acceleration, so the speed is increased at a constant rate.

[Effect of idea]

Therefore, no matter what conditions the vehicle is running under, a device is constructed that engages and operates the hydraulic clutch without causing shock due to disturbances in the hydraulic pressure applied to the clutch, and without slowing down the operation. Embodiments Hereinafter, embodiments of the present invention will be described based on the drawings.

As shown in Figure 2, a running latch (2) to which power from the engine (1) is transmitted, and an external clutch (3)
The power from the running latch (2) is transmitted to the cylindrical input shaft (4) for the running system, and the power from the external clutch (3) drives the external power shaft (5). The power is transmitted to the power transmission shaft (6) that fits inside the human power shaft (4).

As shown in the figure, a clutch case (8) is externally fitted and fixed to the input shaft (4) via a key (7), and
The output gear (9) is fitted on the outside in an idling state, and the input shaft (4)
) A human gear (11) is externally fitted and fixed to a cylindrical intermediate shaft (10) coaxially arranged with the shaft (10).

Moreover, an idle gear (12) and two gears (13) and (14) are located between the output gear (9) and the manual gear (11).
) is formed, and the clutch case (8) transfers the power from the input shaft (4) to the output gear (
9) and the input shaft (4).
) and a second hydraulic clutch (C2) that directly transmits power from the input gear (11) to the input gear (11), and both the first and second hydraulic clutches (CI) and (C2) have a large number of friction plates (15)...
(16)...and hydraulic pistons (17), (18)
), and each hydraulic clutch (c, ), (
Cz) can be set to a transmission state by supplying pressure oil.

Incidentally, the power from the intermediate shaft (10) is transmitted through the speed change bag ff(
A transmission system is formed in such a way that the power is transmitted to the wheels (20) via the motor (19). Further, this transmission system is configured to be installed in an agricultural tractor, and in this transmission system for traveling, it is designed to minimize the generation of shock when changing gears by the operation of the first and second hydraulic clutches (C,) and (C2). 1st
, a system for controlling the pressure of hydraulic fluid to the second hydraulic clutches (C+), (CZ).

In other words, as shown in Fig. 1, pressure oil from the hydraulic pump (21) is sent to the forward/reverse switching valve (22);
2) to the first and second hydraulic clutches (C+).

(C2) Oil passages (23) and (24) that send pressure oil to each
are equipped with electromagnetic proportional pressure reducing valves (Vl) and (VZ), respectively, and these two electromagnetic proportional pressure reducing valves (Vl) and (Vz
) (An example of a valve mechanism) is controlled by an operation signal from a control device (25) that includes a microprocessor (not shown), and the control device (25) is configured to detect the operation position of the valve (22). the changeover switch (26) and the wheel (20
) sensor (S) that detects the acceleration of the running system from the rotation of (
A control system is formed so that a signal from a measuring device (an example of a measuring means) is input, and a program is set for this control device (25) to operate according to the flowchart shown in FIG. When the hydraulic clutch is engaged, the clutch internal pressure is increased at a predetermined rate, and after the hydraulic clutch starts transmission,
A control means (T) is formed to increase the clutch internal pressure at a rate of increase lower than the rate of increase described above, and the operation of the control device (25) will be described below based on a flowchart.

That is, the valve (
22) is detected (#L#2 step), the fourth
As shown in the graph of Figure (a), an operation signal of current value (Imax) is applied to the electromagnetic proportional pressure reducing valve on the pressure oil supply side over time (T,
) is supplied (#3 step), and then the current value of this operation signal is lowered to (Imin) (#4 step)
.

Incidentally, the electromagnetic proportional pressure reducing valves (V, ), (VZ) are configured to increase or decrease the supply pressure of hydraulic oil in accordance with the increase or decrease in the supplied current value, and as mentioned above, the value of the operation signal is changed over time (
The reason why T1) is set larger is to shorten the time required for engaging the hydraulic clutch by narrowing the interval between the friction plates of the hydraulic clutch in advance.

After this, increase the current value of the operation signal at a predetermined rate #5
Step), input the acceleration value (xl) based on the signal from the sensor (S) (Step #6), and compare the predetermined value (α) with this acceleration value (Xυ).
Steps #7 and #8), it is determined whether the hydraulic clutch has reached a half-clutch state and an increase in vehicle speed has started.

Also, when the increase in vehicle speed is recognized in steps #7 and #8, the increase in the operation signal is stopped (step #9), and then the timer is activated (step #10), and the signal from the sensor (S) is activated. Input the acceleration value (X2) based on the result of comparing the predetermined value (α) and this acceleration value (X2) (#12, #13 steps), calculate the acceleration of the vehicle speed. A hydraulic clutch (C) is used to maintain the predetermined value (α).
) is increased, maintained, and reduced (#14, !115116 step).

After the speed increase control continues for a predetermined time (T2), the current value (I
max) at a predetermined rate and set to a completely engaged state (steps #17 and #18).

The operations from step #3 to step #18 are expressed in a graph based on the current value of the operation signal, the vehicle speed, and the vehicle acceleration as shown in FIG. 4 (a).

Drawn as (b), (c), #6 to #9, #11 to #
The 16 steps are called control means (T).

Note that the sensor (S) is connected to the drive shaft (20a) of the wheel (20).
) is configured to detect the rotation of a gear (27) attached to a pickup-type coil (28).

[Another example]

In addition to the embodiments described above, the present invention may be applied to, for example, a transmission system configured in multiple stages, or may be provided in a transport vehicle (also, the control means may be implemented as a hardware combination of comparators, logic gates, etc.). It may be configured.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of the drawing]

The drawings show an embodiment of the hydraulic clutch device for driving a working vehicle according to the present invention, and FIG. 1 is a block diagram of the control system of the device;
Figure 2 is a schematic diagram of the transmission system, Figure 3 is a flow chart showing the operation of the control device, Figure 4 (A) is a graph of the control signal for the electromagnetic proportional pressure reducing valve at the start of travel, and Figure 4 (U
) is a graph representing the vehicle speed at the start of travel, and FIG. 4(C) is a graph representing the acceleration of the vehicle body at the start of travel. “(C)・・・Hydraulic clutch, (S)・・・・・・
Measuring means, (T)...Controlling means, (v)...
...Valve mechanism.

Claims (1)

[Claims] A friction-type hydraulic clutch (C) installed in the running system; a valve mechanism (V) that adjusts the supply pressure of hydraulic oil to the hydraulic clutch (C); and a measuring means (S) that detects the acceleration of the running system.
), and the acceleration in the speed increasing direction of the traveling system during supply of hydraulic oil to the hydraulic clutch (C) is determined based on the detection signal from the measuring means (S), and the value of this acceleration is approximately A hydraulic clutch device for running a working vehicle, which is provided with a control means (T) that adjusts the operation of a valve mechanism (V) to maintain a predetermined value.