JPH0613265B2 - Hydraulic circuit structure of hydraulically controlled clutch and transmission - Google Patents

Description

TECHNICAL FIELD The present invention relates to a hydraulic control type clutch and a hydraulic circuit for a transmission.

<Prior Art> There is a device for automatically controlling a clutch and a transmission of an automobile by hydraulic pressure. The mechanism is a flow control valve that controls the pressure oil discharged from the oil pump to a constant flow rate,
An electromagnetic switching valve that switches the pressure oil controlled to a constant flow rate between the clutch control cylinder side and the transmission control cylinder side, and the pressure oil is switched between the clutch disconnection chamber side and the clutch connection chamber side of the clutch control cylinder. A switching valve to be supplied, a clutch hydraulic pressure control valve for switching and controlling the switching valve, and an electromagnetic pressure control valve for controlling the clutch hydraulic control valve are provided, and the pump discharge pressure oil is cooled and recirculated to the low pressure side tank. It is a configuration provided with an oil cooler.

<Problems to be Solved by the Invention> In the above-described conventional configuration, the hydraulic circuit is complicated, oil may not flow to the oil cooler, and the oil filter is disposed upstream of the discharge side of the pump. The dust sucked from the oil tank or the like may enter the flow control valve arranged between the pump and the oil filter, and hinder the function of the flow control valve.

Further, the pressure oil discharge pump has a large capacity corresponding to the operation of the clutch and the transmission.
Since a large-capacity pump is operated because it is necessary to maintain the pressure of the hydraulic circuit even when the transmission is not operated, the loss of the engine output consumed by this pump is large.

<Means for Solving Problems> The present invention provides a hydraulic circuit structure that solves the above-mentioned conventional problems, and is characterized by a constant flow rate of pressure oil discharged from an oil pump. Control valve, a solenoid switching valve that switches pressure oil connected to a constant flow rate between the clutch control cylinder side and the transmission control cylinder side, and the pressure oil between the clutch control chamber side of the clutch control cylinder. A switching valve for switching and supplying to the clutch connection chamber side, a clutch hydraulic control valve for switching control of this switching valve, an electromagnetic pressure control valve for controlling this clutch hydraulic control valve, and a low pressure side for cooling pump discharge pressure oil. In the hydraulic control circuit with a hydraulic control clutch equipped with an oil cooler that recirculates to the tank, the hydraulic control circuit for the transmission has a large capacity main pump and a small capacity sub-pump. A pump switching valve is provided between the pressure oil discharge flow path of the main pump and sub pump, the supply flow path to the clutch and transmission side, and the flow path to the oil cooler, and on the suction flow path side of both pumps. It has an oil filter installed.

<Operation> In the present invention having the above configuration, the pressure oil required when operating the clutch and the transmission uses the discharge hydraulic pressure of the large-capacity main pump, and the discharge hydraulic oil of the small-capacity sub-pump is passed through the oil cooler during that period. To return to the low-pressure tank. After the clutch and transmission are activated, the pressure oil in the hydraulic circuit is maintained by the pressure oil discharged from the small-capacity sub-pump to maintain the clutch and transmission operating state, and the pressure oil discharged from the large-capacity main pump resists. It is returned to the tank on the low pressure side through the oil coolant having a small amount. Further, in both of the pumps, the oil filter on the suction side filters the oil sucked into the pump, so that the goy and the like are not mixed in the discharged pressure oil.

<Examples> Examples of the present invention will be described below with reference to the drawings. Reference numeral 33 is a flow rate control valve that controls the pressure oil discharged from an oil pump described later to a constant flow rate.

Reference numeral 2 is a pressure oil feed passage for guiding the pressure oil discharged from the oil pump to the clutch side, and 3 is a pressure oil feed passage for guiding the pressure oil to the transmission side. Reference numeral 4 is an electromagnetic switching valve that switches and splits the clutch side and the transmission side.

A clutch control cylinder 8 is provided on the clutch side. This clutch control cylinder 8 has a piston 9
Thus, a clutch disengagement chamber 10 and a clutch connection side chamber 11 are formed, and both chambers 10 and 11 are communicated with each other through an orifice 12 provided in the piston 6.

The circuit configuration for controlling the supply of pressure oil to the clutch control cylinder 8 is as follows. A circuit 6 communicating from the pressure oil supply passage 2 to the clutch disengagement side chamber 10 via a clutch pressure oil control valve 5, and a check valve 13 and a switching valve from the pressure oil supply passage 2.
A circuit 15 communicating with the clutch disengagement side chamber 10 via 14 and an electromagnetic pressure control valve 16 arranged in a relief passage 17 communicating with the low pressure side for controlling the clutch hydraulic pressure control valve 5 are provided in the circuit 6. Is provided with a back pressure valve 7 which supplies pressure oil to the clutch disengagement side chamber 10 while always controlling the pressure oil to a constant pressure.

On the other hand, the transmission side has a select cylinder for selectively operating the transmission (not shown) and a shift cylinder for performing the shift operation.
Supply the pressure oil to the select cylinder and discharge it to the low pressure side, and to the shift cylinder,
It also has a shift / select control valve consisting of an electromagnetic shift valve for discharging to the low pressure side and a manually operated valve.

Further, a clutch manual control valve 24 is provided on the clutch side.

The clutch manual control valve 24 is arranged between the clutch hydraulic pressure control valve 5 and the electromagnetic pressure control valve 16 in relation to the switching valve 14. That is, the clutch pressure oil control valve 5 and a valve portion for opening and closing the relief passage 17 of the electromagnetic pressure control valve 16,
A valve portion for opening and closing a passage 19 connected to the operation port on the right side of the switching valve 14 in the drawing of the switching valve 14 from the pressure oil feed passage 2 in front of the check valve 13 and the left side of the switching valve 14 in the drawing. Of the operation pressure of the electromagnetic pressure control valve 16 and a valve portion for relieving a constant pressure signal pressure supplied to the operation port of the circuit 6 through the passage 20 to the low pressure side, and a hydraulic control valve 25 having the same function as the electromagnetic pressure control valve 16. There is.

In addition, the oil cooler 40 that communicates with the discharge side of the oil pump
Is provided, and when the oil temperature reaches a predetermined temperature or higher, the oil is cooled and recirculated to the low pressure side tank 42.

According to the present invention, in the above hydraulic control type clutch and hydraulic control circuit for a transmission, the oil pump is provided with two pumps, a main pump 1a having a large capacity and a sub pump 1b having a small capacity. And sub pump 1b
And pressure oil discharge flow paths 44a and 44b, a supply flow path 45 to the clutch and transmission side, and a flow path to the oil cooler 40
A pump switching valve 41 is provided between the two pumps 46, and both pumps 1a and 1b are provided.
A hydraulic circuit in which an oil filter 43 is installed is provided on the suction flow path 47 side.

Next, the operation of the above configuration will be described. First, normally, the clutch manual control valve 24 has a relief passage 17 between the clutch hydraulic pressure control valve 5 and the electromagnetic pressure control valve 16.
Is opened to establish a communication state between the passages 18 and 19, and the relief circuit of the passage 26 and the hydraulic control valve 25 is closed. This allows
The clutch hydraulic pressure control valve 5 is controlled by operating the electromagnetic pressure control valve 16, and the switching valve 14 is controlled to be switched by the control of the clutch hydraulic pressure control valve 5, and the clutch connection side chamber 10 and the clutch disengagement side chamber 11 are supplied. By supplying pressure oil of a certain pressure or more, the clutch is brought into contact, and the switching valve 14 reliefs the supplied pressure oil to the low pressure side to perform the clutch disengagement operation.

On the other hand, the transmission is shifted and selected by a shift / select control valve to a predetermined range.

Further, the electromagnetic switching valve 4 controls the switching between the clutch control cylinder side and the transmission control cylinder side by the pressure oil from the oil pump.

Therefore, when operating the clutch and the transmission, the pump switching valve 41 supplies the pressure oil discharge passage 44a of the main pump 1a and the supply passage 45 to the clutch and the transmission side so that a large amount of pressure oil of the main pump 1a is supplied. To communicate. At this time, by switching the pump switching valve 41, the pressure oil discharge flow path 44b of the sub pump 1b communicates with the flow path 46 to the oil cooler 40, and the discharge pressure oil of the sub pump 1b flows back to the tank 42 through the oil cooler 40. To do. After the operation of the clutch and the transmission, the pump switching valve 41 is switched, and the pressure oil discharge passage 44b of the sub pump 1b is switched.
And the supply flow path 45 are communicated with each other to supply a small amount of pressure oil necessary for maintaining the operating state of the clutch and the transmission. At this time, the pressure oil discharge passage 44 of the main pump 1a
a communicates with the flow path 46 to the oil cooler 40, and the main pump 1
The pressure oil discharged from a is returned to the tank 42 via the oil cooler 40.

Further, the oil pumped up from the tank 42 by the main pump 1a and the sub pump 1b is filtered by the oil filter 43 on the suction passage 47 side.

<Effects of the Invention> As described above, according to the present invention, in the hydraulic control circuit for the hydraulically controlled clutch and the transmission, the oil pump is provided with two main pumps having a large capacity and a sub pump having a small capacity, and the clutch and the transmission are operated. Occasionally, the hydraulic circuit structure supplies the discharge pressure oil from the main pump side and controls the pump switching valve to maintain the operating state with the discharge pressure oil from the sub-pump after the operation. There is no loss, and the cooling efficiency of oil is good and the performance is improved. Further, the provision of the oil filter on the suction flow rate side of the pump eliminates the inconvenience of dust flowing into the flow rate control valve, and has the advantage of reliably performing constant flow rate control of the pump discharge pressure oil.

[Brief description of drawings]

FIG. 1 is a pressure oil control circuit diagram of the present invention. 1a ... main pump, 1b ... sub pump, 2,3 ... pressure oil supply passage, 4 ... electromagnetic switching valve, 5 ... clutch hydraulic control valve, 8 ...
Clutch control cylinder, 14 ... switching valve, 16 ... electromagnetic control valve, 40 ... oil cooler, 41 ... pump switching valve, 42 ... tank, 43 ... oil filter, 44a, 44b ... pressure oil discharge passage, 45
… Supply channel, 46… channel, 47… suction channel.

Claims (1)

[Claims] 1. A flow rate control valve for controlling a constant flow rate of pressure oil discharged from an oil pump, and an electromagnetic switching valve for switching the constant pressure flow rate controlled pressure oil between a clutch control cylinder side and a transmission control cylinder side. And a switching valve for switching and supplying the pressure oil to the clutch disconnection chamber side and the clutch connection chamber side of the clutch control cylinder, a clutch hydraulic control valve for switching control of the switching valve, and controlling the clutch hydraulic control valve. In a hydraulic control clutch equipped with an electromagnetic pressure control valve and an oil cooler that cools pump discharge pressure oil and recirculates it to a low-pressure tank, a hydraulic control circuit for a transmission has a large-capacity main pump and a small-capacity sub-pump. The main pump and sub pump are provided with a pressure oil discharge flow path, a clutch and a supply flow path to the transmission side, and an oil cylinder. Pump the switching valve is provided, the hydraulic control clutch which in the suction flow path of both pumps, characterized in that installed an oil filter, a hydraulic circuit structure of the transmission between the flow path to La.