JPS60256629A - Hydraulic clutch cylinder control device - Google Patents

Abstract

PURPOSE:To obtain smooth speed changing by providing a pressure control mechanism having an electromagnetic proportional relief valve and an electric control unit so that the liquid pressure to be supplied to a clutch cylinder can be increased according to a pressure increasing curve most appropriate for the vehicle running condition. CONSTITUTION:A pressure control mechanism 25 for controlling the pump liquid pressure is composed of an electromagnetic proportional relief valve 26 and an electric control unit 27. The set pressure of the electromagnetic relief valve 26 is set by a command signal from the electric control unit 27. The electric control unit 27 receives the vehicle speed, the speed of the engine for driving the transmission and signals from a sensor for detecting the shift position of a directional switching valve 3 and others to calculate the vehicle running condition, and transmits to the electromagnetic proportional relief valve 26 the optimum pressure increasing curve of the clutch cylinder liquid pressure on engagement of the clutch which is obtained from the vehicle running condition.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention mainly controls a hydraulic clutch for shifting of a power shift type transmission of a vehicle.

This invention relates to a hydraulic pressure control device.

For example, as shown in Fig. 1, this type of conventional device uses a directional control valve (3) that receives pressurized liquid from a pump (2) whose pressure is limited by a pressure control mechanism (1) to control the transmission. a hydraulic clutch (4) provided in a plurality of gear trains;
(5) l Among (6), for example, the pump pressure fluid is introduced into the clutch cylinder (force) of the clutch (4) when the clutch is off, and the clutch cylinder (8) of the clutch (6) when the clutch is on is connected to the tank (9). As a result, the shift latch (4) is turned on by the pressure fluid filled in the clutch cylinder (7), and the pressure in the clutch cylinder (8) of the clutch (6) decreases as shown by the broken line in Figure 2. It becomes Yosikura Chio 7.

The pressure control mechanism (1) includes a relief valve (l) and a cylinder Q2+ that adjusts the spring force of a spring aυ that determines its set pressure.
It consists of a throttle with a check valve +131, and operates as follows. When an empty clutch cylinder, for example, the clutch cylinder (7), is filled with pressure fluid, the supply fluid pressure becomes a low pressure corresponding to the pressure fluid filling resistance to the clutch cylinder (force), so the head chamber of the cylinder (12) The pressure fluid in (14) is pushed by the spring (lυ) and is discharged through the check valve (161) to the flow path αη, and the set pressure of the relief valve (II is lowered by the extended spring αυ. Cylinder(
When the filling of pressure fluid to the pump is completed, the clutch (4) starts to engage as shown in Figure 2, and since the supply pressure fluid is very small and there is a lot, most of the pressure fluid from the pump (2) is used. It passes through the relief valve (10), the torque converter α9, the cooler (a), and the lubricant distributor C91), and then flows back to the tank (9). Therefore, the supply liquid pressure becomes the pressure set by the IJ IJ-7 valve 00), but at the same time, a part of the pressure liquid flows into the head chamber a41 through the throttle a81 and compresses the spring αυ, causing the relief valve to flow into the head chamber a41. The set pressure of QO) gradually increases. As a result, the supply fluid pressure rises, and even after the clutch (4) is connected, it further rises and when the head chamber 04) reaches its maximum capacity, the flow of pressure fluid to the head chambers 0/D is stopped and the IJ valve(
10) is the maximum set pressure.

Similarly, there are two low pressure IJ and IJ- valves that limit the inflow pressure to the torque converter a9.

In the conventional device as mentioned above, the clutch cylinder, 'da'
17) The increasing force curve of the clutch cylinder hydraulic pressure from the completion of EE fluid filling to the completion of j5'/f connection (hereinafter referred to as clutch connection) is uniquely determined by the structure of the hydraulic pressure circuit of this hydraulic pressure control device. For example, the boost pressure curve will be as shown by the dashed line in FIG. 2. However, the optimal curve for the boost pressure curve differs depending on factors such as differences in clutch capacity for each speed stage, differences in clutch upshifts and downshifts, and differences in vehicle speed and rotational speed of the engine that drives the transmission. It becomes difficult to obtain a boost pressure curve, resulting in problems such as a time-consuming shift and a shock to the driver when shifting.

SUMMARY OF THE INVENTION An object of the present invention is to provide a hydraulic clutch cylinder control device that can smoothly and quickly change gears using relatively simple means.

In order to achieve the above object, the hydraulic clutch 7-ring control device according to the present invention provides a control device for driving a vehicle between a directional control valve that selectively connects a plurality of clutches/cylinders to a pump and a tank, and a pump. Based on the condition, the clamping force when the clutch is connected is 1) 71-Yo. □7E, -7, □. O6.

)・1□ A pressure control mechanism consisting of an electric controller and an electromagnetic relief valve whose set pressure is controlled by a command signal from the electric controller is provided.

The present invention will be explained below based on embodiments shown in the drawings. 6th
In the figure, the directional control valve (3) is connected to the clutch (4), (
5), +6) clutch/linda (force, (2L'
(8) is selectively connected to the pump (2) and tank (9), and the excess liquid is transferred to the pressure control mechanism (from 25+ to torque converter α1, cooler (to), lubricating liquid distributor 0
1) and is refluxed to the tank (9). The above configuration is the same as the conventional device shown in FIG.

In the present invention, the pressure control mechanism (25) that limits the pump hydraulic pressure includes an electromagnetic proportional relief valve (26) and an electric controller 0.
7).

The set pressure of the electromagnetic proportional IJ IJ valve G61 is set by a command signal from the electric controller (27). The electric controller (27) calculates the operating state of the vehicle by receiving signals from a sensor that detects the vehicle speed, the rotational speed of the engine that operates the transmission, the /7 position of the directional control valve (3), etc. The optimum increase force curve for the clutch cylinder hydraulic pressure when the clutch is engaged is determined based on the vehicle operating condition and is output to the electromagnetic proportional relief valve. Boost force curve I, n, m...
・is obtained.

In the configuration described above, for example, a hydraulic clutch (4
), +5) clutch/cylinder (force, (2 seconds) is in communication with the tank (9) and the clutch cylinder (8) of the hydraulic clutch (6) is in communication with the pump (2), then the direction change By switching the valve (3), the clutch cylinder (force) of the hydraulic clutch (4) is communicated to the pump (2) and the hydraulic clutch (6
)'s clutch/cylinder (8) is connected to the tank (9), the hydraulic clutch (6) will not be clutch-off,
Until now, the empty clutch cylinder (pump (2)
) flows in. In this case, the directional valve (3)
The electric controller (27) that receives the shift change signal from the sensor that detects the /foot position is an electromagnetic proportional relief valve (26).
Set the pressure to low according to the pressure fluid filling resistance to the clutch/su/da (force).

When the clutch cylinder (7) is filled with pressure fluid, the clutch is connected to the b1 clutch cylinder (a very small amount of pressure fluid is sufficient for the force), so excess fluid is removed by the electromagnetic proportional relief valve (
26), flows back to the tank (9) via the torque converter a, cooler (20), and lubricant distributor Cυ. When the clutch is connected, the electric controller (2'7) controls the set pressure of the electromagnetic proportional relief valve (26) based on the optimum boost pressure curve when the clutch is connected, which is determined based on the vehicle operating condition. Therefore, the clutch cylinder hydraulic pressure, which is limited by the electromagnetic proportional relief valve (c), increases to a pressure suitable for the vehicle operating condition and connects the clutch.

When the clutch is connected, the electromagnetic proportional IJ IJ valve (
26) is boosted to the maximum setting pressure to maintain clutch connection, and excess fluid is passed through the electromagnetic proportional IJ valve (26) to the torque converter (IL cooler (A), lubricating fluid distributor Qυ
The water is refluxed to the tank (9).

Similarly, in this embodiment, the timing of hydraulic pressure control at the time of clutch switching is calculated by the electric controller 9 which receives the gear shift signal from the sensor that detects the shift position of the directional control valve (3). If a directional switching valve (3) is used that is operated by an electrical command signal, such as an electromagnetic switching valve, the electrical command signal may be received by an electric controller instead of the signal from the sensor. good.

As explained above, in the present invention, the pressure control mechanism consisting of the electromagnetic proportional relief valve and the electric controller is used to increase the fluid pressure supplied to the clutch cylinder when the clutch is engaged using a boost pressure curve that is optimal for the vehicle operating condition. Therefore, the gear shifting operation can be performed smoothly and quickly with a simple configuration.

[Brief explanation of the drawing]

Fig. 1 is a hydraulic circuit diagram of a conventional device, Fig. 2 is a chart showing pressure changes of pump hydraulic pressure and clutch/cylinder hydraulic pressure in a conventional device, and Fig. 6 is a hydraulic circuit diagram showing an embodiment of the present invention. ,
FIG. 4 is a chart showing the increased state of the clutch/cylinder fluid pressure when the clutch is connected in the device of the present invention. 2 g y 7'/6" degree directional control valve/4/5/6
-bj'hydraulic clutch, 7,8.28...clutch cylinder '□da, 25...pressure control mechanism, 26...electromagnetic proportional +717-7 valve, 27...electric controller. Fig. 1 2 Fig. 2 Ginma t Fig. 3 Fig. 4 JP-A t

Claims (1)

[Claims] Between the pump and the directional control valve that selectively connects the plurality of clutch cylinders to the pump and the tank, there is a valve for calculating the increase pressure curve of the latch cylinder fluid pressure when the clutch is connected based on the driving condition of the vehicle. A hydraulic clutch cylinder control device comprising a pressure control mechanism consisting of an electric controller and an electromagnetic proportional relief valve whose set pressure is controlled by a command signal from the electric controller.