JPH02176220A - Clutch actuating device for tractor and the like - Google Patents

Abstract

PURPOSE:To enable a clutch to be actuated by a roughly constant footing force regardless of wear of clutch discs by detecting actuating pressure when the clutch discs come in contact with one another by means of clutch engagement, and thereby controlling auxiliary actuating force for clutch engagement. CONSTITUTION:The time when the clutch discs of a clutch 1 start coming in contact with one another is detected by means of an engine sensor 23, an input shaft sensor 24, a stroke sensor 22 and the like. When the input shaft sensor 24 detects the rotation of an input shaft upon contacting of the clutch disc, the telescoping position of a clutch cylinder 20 is detected by the stroke sensor 22 at the time in order to detect initial actuating pressure, then, it is subtracted from control pressure by a present pressure control valve 21 so that the result shall be auxiliary actuating force for making connection with the clutch 1. By this constitution, connection is made with the clutch 1 under appropriate pressure while the clutch actuating pressure of a pressure control valve 21 is being corrected regardless of wear of the clutch 1. A driver therefore can actuate the clutch by applying constant footing force at all times regardless of wear of the clutch discs.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a clutch operating device for a tractor or the like.

BACKGROUND ART AND PROBLEMS TO BE SOLVED BY THE INVENTION When shifting gears manually, if the clutch wears out, the timing of the clutches during shifting shifts sequentially.

Due to wear of the clutch disc, the cutting position becomes earlier and the person's position becomes later. This invention adjusts such timing deviations as the clutch wears out.

Means for Solving the Problems The present invention provides a clutch operating device for a tractor, etc., which detects the operating pressure when a clutch disk is in contact with the clutch due to a clutch engagement operation, and controls an auxiliary operating force for clutch engagement. The structure is as follows.

Functions and Effects of the Invention When the engine is driven, power is transmitted to the transmission via the clutch, and the transmission is transmitted by the speed change operation of the transmission. The clutch is turned on and off by operating the clutch pedal when the driver is performing manual gear shifting, and when the driver is performing automatic gear shifting, the clutch is turned on and off at a fixed timing as the gear is shifted using a gear shift operation switch, etc. Off, it's activated a lot.

In this way, when the latch is turned off, the operating pressure is set to the maximum pressure, etc., but when moving from the off state to the on state,
When the clutch disc of the clutch starts to make contact, the operating pressure at this time is detected, and this operating pressure is controlled to decrease from the current pressure to set the auxiliary operating force.

In this way, when the clutch disc operated by the operator wears out due to use, the operating pressure when the clutch disc contacts changes, and the auxiliary operating force is controlled accordingly. Clutch operation can be performed with a constant pedal force, maintaining a stable operating feeling, and does not require manual adjustment, making it simple and easy.

Embodiment When rotating, the tractor body is equipped with an engine (5) at the front, has a front axle steered by a steering wheel, and rear wheels (6), and uses the engine (5) to transmit power. It has a four-wheel drive configuration. These transmission configurations transmit power from the engine (5) to the rear wheels (6) through the clutch (1), the main transmission (7), the auxiliary transmission W (8), etc., and the engine (5). 5) to the PTO clutch (9
] to the power take-off shaft (11) at the rear of the vehicle body. (121 is the clutch (
1) is a clutch pedal that operates.

The main transmission (7) and the sub-transmission (8) each have a suitable number of transmission gears that are operated by hydraulic pressure.

Electromagnetic speed change control valve (1 m (+4)), this speed change control valve (13) (hydraulic speed change cylinder Cl5 which is switched by 141 and operates the speed change gear) (l
e, and a pressure control valve (m, etc.) that controls the pressure of the hydraulic circuit for the speed change operation each time the speed change control valve t+31 fllll is operated, and each speed change cylinder (ISI (IG)) is equipped with a pressure control valve (m, etc.) that detects the amount of expansion/contraction. Stroke sensor flEI (
+9 is provided.

The obstacle sensor (3) consists of an ultrasonic sensor and is provided on the front and rear sides of the vehicle body. When moving forward, the obstacle sensor (3) on the front side is
F) detects obstacles on the field in the front position, and when traveling in reverse, the rear obstacle sensor (3R) detects obstacles in the rear position.

When the clutch (1) is released, the clutch disc (1) is pushed back by the elastic force of the spring by releasing the clutch valves (1, 5), and the hydraulic pressure of the clutch cylinder ffQ is pushed back, and the clutch disc is brought into contact with the clutch, and the clutch becomes in the human position where the clutch is connected. When disengaging, the clutch disc interval is opened by depressing the clutch pedal Uδ or by feeding the clutch cylinder 4 through the hydraulic control valve (21).In the case of an automatic clutch (1), the clutch cylinder c! The pressure control valve 21) which controls this oil pressure, and the clutch cylinder 12 [
A stroke sensor (2δ is provided) that detects the amount of expansion and contraction of 1. C'41 is an engine sensor that detects the engine rotation speed, and C'41 is a main transmission (
7) is an input shaft sensor that detects the rotation speed of the input shaft. These engine sensors (to) and input shaft sensor Q4
The power transmission status, slip, etc. of the clutch (1) are detected based on the difference between the two.

These engine sensor (to), input shaft sensor Q4, stroke sensor eδ, etc. detect the time when the clutch disc of the clutch (1) starts contacting. When this clutch disk comes into contact, if the input shaft sensor 4 detects rotation of the input shaft, the stroke sensor (23) at this time detects rotation of the input shaft.
Detecting the extended/contracted position of the clutch cylinder 12G by
The initial operating pressure is set as Pl, which is reduced from the control pressure by the current pressure control valve port) and is used as an auxiliary operating force for connecting the clutch (1).

The controller I29 is a microcomputer (CPU
), the automatic transmission 1 (21 and the check device (4)
etc., and controls the operation parts ce, such as operation switches, etc.
A display section (5) etc. for displaying each operating section etc. is provided. (
Reference numeral 21 denotes a clutch operation switch for automatically operating clutch +11, and this clutch operation switch +29 is turned on when automatic gear shifting is to be performed.

The running speed of the vehicle is changed by manual shifting and automatic shifting. During manual shifting, the clutch (1) is operated by operating the gear shift lever and the clutch pedal (121).
In automatic shifting, the main transmission (7) or the auxiliary transmission (8) is decelerated or accelerated by selecting and pressing the speed change switch on the operation unit 2Q. This operation is.

When the speed change switch is selected and pressed, clutch cylinder 4 is operated and clutch (1) is disengaged. When the disengaged position of this clutch (1) is detected by the stroke sensor (Inc.), the shift control valve (13041) and the pressure control valve ( 1 force is actuated, the shift cylinder (19 (IQ) is actuated under a predetermined pressure, and the shift gear is operated. The operation of this shift gear is activated by the stroke sensor (18 (l)).
When detected, the clutch cylinder 1 is operated under the hydraulic pressure controlled by the pressure control valve (21), and the clutch (11) is connected and operated by the return spring.

When the engagement of the clutch (1) is detected by the stroke sensor (2X5), the current shift position is displayed on the display section.

Control of the clutch (1) in such a speed change operation is performed as shown in FIG. Initially, the auxiliary operating force was set to the minimum pressure, and the talatch petal tta
In this case, steps ①, ②, and ③ are performed under this set auxiliary pressure.

When the disengaged position of the clutch (1) is requested, the disengaged pressure of the pressure control valve +211 is set to the maximum pressure through steps ■, ■, ■, or ■; The control output of the pressure control valve +211 is not performed.When the clutch (1) is automatically connected from the disengaged state to the on position, the pressure control valve 121) is set to the current pressure in steps ■, ■, O10, 01O1O. On the other hand, the pressure is controlled to set the auxiliary operating force, and the clutch (1) is connected under an appropriate pressure while correcting the clutch operating pressure of the pressure control valve (21) regardless of the wear of the clutch (1).

PO is the initially set operating pressure. Pl is the operating pressure detected by the detection of the start of contact between the discs of the clutch (11), and the operating pressure is calculated according to the interval until the start of contact between the clutch discs detected by the stroke sensor (2X5).This operating pressure is the current The pressure by the pressure control valve G!+1 is reduced and is newly set as the auxiliary operating force. Pl is the operating pressure after setting the auxiliary operating force. When the clutch (1) is connected, this is detected by the stroke sensor. It is detected by L2δ and the output of the pressure control valve (21) is turned off.

Note that the present invention can also be applied to a speed change clutch in which each speed change gear itself has a clutch and is operated on and off by hydraulic pressure. In this case, it is best to control the pressure control valve (■).

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a block diagram, FIG. 2 is a block circuit diagram, and FIG. 3 is a partial flowchart. In the figure, code (1) is a clutch, and code (2) is an automatic transmission. r2 [I is the clutch cylinder, I21) is the pressure control valve,
Qδ is the stroke sensor, (to) is the engine sensor, +
241 indicates an input shaft sensor.

Claims (1)

[Claims] 1. A clutch operating device for a tractor or the like, which detects operating pressure when a clutch disk contacts a clutch due to a clutch engagement operation, and controls an auxiliary operating force for clutch engagement.