JPH0478863B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a constant pressure valve that is installed in a hydraulic circuit and lowers the level of supplied pressure oil to a constant value set by a spring and outputs the same.

More particularly, the present invention relates to a detent regulator valve disposed between a hydraulic power source and a throttle valve.

Conventionally, as a detent regulator valve that outputs detent pressure for determining a downshift speed point to each shift valve, as shown in FIG. A first land 104 that opens and closes the drain port 101, a second land 105 that opens and closes the drain port 103, and the out port 1.
02, and has an oil chamber 106 between the first land 104 and the second land 105. One side receives the spring load of a spring 107 placed backwards from above, and the other side receives the output of the out port 102. A device having a spool 108 that is displaced in response to hydraulic pressure or pressure oil supplied to the import 101 is known. Then, the detent regulator valve adjusts the opening areas of the import 101 and drain port 103, and the out port 102.
It outputs hydraulic pressure or pressure oil that is regulated to a constant pressure.

The detent pressure is input as a downshift signal pressure to each shift valve via the throttle valve when the amount of depression of the accelerator pedal exceeds a predetermined value, and is used to determine the downshift shift point.
The detent regulator valve regulates the line pressure, which increases as the accelerator pedal is depressed, as input oil pressure, and outputs it as a constant detent pressure. As mentioned above, in the constant pressure valve used as a conventional detent regulator valve, the hydraulic pressure supplied from the import 101 suddenly increases.
The positions and sizes of the lands and ports are adjusted so that when the oil pressure in the oil chamber 106 increases and the spool 108 is displaced upward in the drawing, and the import 101 is closed by the first land 104, the drain port 103 is opened by the second land 105. It was set. For this reason, solids such as cutting chips present in the pressure oil enter the drain port 103 when the drain port 103 is opened, and when the drain port 103 attempts to close, it may become caught between the port edge and the land edge, resulting in a valve stem. This valve stem restricts the displacement of the spool 108, making it impossible to output detent pressure at a predetermined level, resulting in problems such as not being able to perform a gear shift at the correct downshift shift point, resulting in poor drive feeling.

Therefore, the object of the present invention is to provide a detent regulator valve that can reliably prevent such valve sticking by always keeping the flow passage cross-sectional area of the drain part of the constant pressure valve constant and output a constant detent pressure at all times. Our goal is to provide constant pressure valves.

The above object of the present invention is achieved by the following configuration.

i.e. the import where the line pressure is supplied,
A valve hole in which an out port and a drain port that communicate with the shift valve via the throttle valve are opened when the throttle opening is equal to or greater than a predetermined value, a spring disposed in the valve hole, and a spring slidable in the valve hole. a spool that is inserted into the spool and is displaced by a balance between a biasing force applied to one side by the hydraulic pressure and a biasing force applied to the other side by the spring when hydraulic pressure from the out port is applied; a first land that opens and closes the input port to the out port according to displacement; and a first land that fits into the inner circumferential wall of the valve hole located between the out port and the drain port to always close the drain port and the first land. This is a constant pressure valve for a hydraulic control circuit of an automatic transmission for a vehicle, which has a second land that increases or decreases the fitting length according to displacement of the spool.

Next, the present invention will be explained based on the embodiment shown in FIG.

A indicates such a constant pressure valve of the present invention, 1 is an import port, 2 is an out port, 3 is a drain port,
4 is a spool, 5 is a spring installed behind it, 6 is the first land of the spool 4 that opens and closes the import 1, 7 has a diameter larger than the first land 6, and adjusts the amount of oil discharged from the drain port 3. The second land 8 is an oil chamber between the first land 6 and the second land 7 and is always in communication with the out port 2.

In this constant pressure valve A, the oil pressure supplied from the import 1 increases, thereby increasing the oil pressure in the oil chamber 8, and the spool 4 is displaced upward in the figure from the position shown by the dashed line to the position shown by the solid line, and With 6 definitely blocking import 1,
The drain port 3 is still blocked by the second land 7, and the amount of oil discharged from the drain port 3 increases or decreases due to the peripheral wall 7A of the second land 7 and the inner peripheral wall 9A of the valve hole 9 into which the spool 4 is fitted. gap S between
This is done by changing the distance L between the end 7B of the second land 7 on the oil chamber 8 side and the end 3B of the drain port. Therefore, since the size of the gap S is constant and does not change, it is reliably prevented that solid objects such as cutting chips that cause valve sticks will become trapped and the valve will not move.

In the above invention, the output oil pressure is adjusted by increasing/decreasing the amount of pressure oil supplied from the import 1 and increasing/decreasing the amount of oil drained from the drain port 3, thereby maintaining the output oil pressure from the out port at the set value. In order to adjust the output oil pressure from the out port, it is possible to increase or decrease the amount of oil discharged from the drain port and to partially discharge the pressure oil at the output pressure oil supply destination. The description will be based on the hydraulic control device for a vehicle automatic transmission shown in FIG.

10 is an automatic transmission for a vehicle that combines a hydraulic torque converter 11 and a transmission 12 with 4 forward speeds and 1 reverse speed; 30 is a hydraulic pressure that automatically changes the speed of the automatic transmission for a vehicle according to the driving conditions of the vehicle; It is a control device.

The transmission 12 includes a multi-disc clutch C0 operated by a hydraulic servo 13 and a multi-disc brake B0 operated by a hydraulic servo 14.
Overdrive device 15 for obtaining 4th speed
, a multi-disc clutch C1 operated by the hydraulic servo 16, a multi-disc clutch C2 operated by the hydraulic servos 17 and 18, a multi-disc brake B1 operated by the hydraulic servo 19, and a multi-disc brake B1 operated by the hydraulic servos 20 and 21. It is equipped with a plate brake B3 and an underdrive device 22 for obtaining three forward speeds and one reverse speed. Hydraulic control device 3
0 is an oil sump 31, an oil pump 32 that is driven by the engine and discharges pressure oil from the oil sump 31 to the oil passage 201, and a line that regulates the oil pressure in the oil passage 201 according to vehicle running conditions such as vehicle speed and throttle opening. The primary regulator valve 33 is used to adjust the pressure of surplus oil discharged from the primary regulator valve 33 into the oil passage 202 according to the vehicle running conditions, and supply hydraulic oil to the torque converter 11 and transmission 12. The secondary line regulator valve 34 supplies lubricating oil to the oil cooler and circulates hydraulic oil to the oil cooler, and regulates the line pressure supplied from the oil passage 201 according to the throttle opening of the engine. It has a throttle valve 35 that outputs throttle pressure, and a spool 361 that is linked to a shift lever installed on the driver's seat, and has P (park), R (reverse), N (neutral), and D (drive) set by the driver. , 2 (second), and L (low) positions, a manual valve 36 that connects the oil passage 201 with line pressure supply oil passages 205 to 208 to the hydraulic servo, etc., and an output shaft 23 of the automatic transmission.
A governor valve 37 is attached to the oil passage 204 and outputs the line pressure supplied from the oil passage 206 to the oil passage 204 as governor pressure corresponding to the output shaft rotation speed.
The spool 381 has a spool 381 to which the governor pressure of 04 and the throttle pressure of the oil passage 203 are applied from the other side, and when the manual valve 36 is set to the D range and the 2 range, the spool 381 is Oil passage 210 connected to hydraulic servo 18 of brake B1 when set downward in the figure
is discharged through the 2-3 shift valve 39 and the oil passage 209 to set the first speed, and when the spool is set upward in the figure, the oil passage 206 and the oil passage 209 are connected to engage the brake B1 and the second speed is set. 1-2 shift valve 38, which also inputs the governor pressure and throttle pressure, maintains the oil passage 210 at line pressure when the spool 391 is set to the lower position in the figure, and also controls the clutch C2.
Pressure is discharged from the connecting oil passage 211 to the hydraulic servo 18 to set the second speed, and when the spool is set upward in the figure, the oil passage 209 and the oil passage 211 are connected to engage the clutch C2 and brake B1 is activated. It is equipped with a 2-3 shift valve 39 that is released to set the third speed, and a spool 401 that is also displaced due to the balance between the governor pressure and the throttle pressure. The communication oil passage 212 is depressurized, and the communication oil pressure 213 to the hydraulic servo 13 of the clutch C0 and the manual valve 3 are removed.
3, the oil passage 212 is connected to the oil passage 201 to which line pressure is supplied through 3 to set the third speed, and when the spool is set upward in the figure, the oil passage 212 and the oil passage 201 are connected to engage the brake B0. , a 3-4 shift valve 40, a 2-3 shift timing valve 41, and a 3-4 shift valve 40, which discharges pressure from the oil passage 213 and releases the clutch C0 to set the fourth gear.
2 kick-down orifice control valve 42,
Low coast modulator valve 43, reverse brake sequence valve 44, governor modulator valve 45, cutback valve 46, D-2 down timing valve 47, C0 exhaust valve 48 for discharging pressure from the hydraulic servo 13 of clutch C0, reverse Clutch sequence valve 49, accumulator 50 for clutch C1, accumulator 51 for brake B1, inner piston accumulator 52 for clutch C2, control switch 53,
It consists of an electromagnetic solenoid valve 54 and a detent regulator valve 70.

The detent regulator valve 70 has the configuration of a constant pressure valve according to the present invention, and includes an import port 71 that communicates with the oil passage 201 and is supplied with line pressure, an out port 72 that communicates with the detent pressure output oil passage 221, and a drain port. 73, a spool 74, a spring 75 placed behind one side, a first land 76 that opens and closes the import 71, a second land 77 that always overlaps and closes the drain port 73, and a first land that constantly communicates with the out port 72. 76 and an intermediate oil chamber 78 between the second land 77, and the spool 74 is displaced by receiving the spring load of the spring 75 from one side and the detent pressure of the oil chamber 78 from the other side, so that the line pressure of the oil passage 201 is As a result, when the detent pressure becomes high, the spool 74 is displaced upward in the figure, and the first land 76 closes the import 71, and even when the line pressure supply to the oil chamber 78 is reduced, the second The land 77 closes the drain port 73, leaving an overlap between the outer periphery of the second land 77 and the inner periphery of the valve hole, as in the embodiment shown in FIG. It is determined by the length of the distance L.
The detent pressure output from the outport 72 to the oil passage 221 is determined by the oil pressure when the throttle pedal is suddenly depressed due to sudden acceleration of the vehicle and the kick-down plug 351 provided in the throttle valve 35 is significantly displaced upward in the figure. The passage 221 is connected to the detent pressure supply oil passage 2 via the kickdown plug 351.
22, each spool 38 of the 1-2 shift valve 38, 2-3 shift valve 39, and 3-4 shift valve 40
Detent pressure is applied to 1,391,401 in the same direction as the throttle pressure to cause a sudden downshift, and the output shaft torque of the automatic transmission increases rapidly accordingly. In this state, the detent pressure is determined by the amount of oil drained from the drain port 73, the gap between the kickdown plug of the throttle valve and the valve hole, the 1-2 shift valve, the 2-3 shift valve, and the 3-4 shift valve. The set oil pressure is determined by the amount of pressure oil leaking from the gap between the spools and the valve hole into which these spools are fitted.

As described above, the constant pressure valve for a detent regulator valve of the present invention has the following effects.

That is, the second land fits into the inner circumferential wall of the valve hole located between the out port and the drain port and always closes the drain port.
Pressure oil is discharged from the drain port through a gap between the outer circumferential wall of the second land and the inner circumferential wall of the valve hole, and an increase or decrease in the amount of discharged oil is caused by a second discharge port that closes communication between the out port and the drain port. Since this is done by changing the fitting length of the land, the cross-sectional area of the flow path in the drain portion can always be kept constant, and valve sticking can be reliably prevented.

The detent pressure is determined by the length of the second land that closes the communication between the out port and the drain port. In this way, a constant detent pressure can always be output to each shift valve.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a conventional constant pressure valve, Fig. 2 is a sectional view of a constant pressure valve of the present invention, and Fig. 3 is a hydraulic circuit diagram of a hydraulic control device for an automatic transmission for a vehicle, showing an embodiment of the related invention. It is. In the figure, 1,71...import, 2,72...
Outport, 3,73...Drain port,
4,74...Spool, 5,75...Spring, 6,76...1st land, 7,77...2nd
Land, 8, 78...Oil chamber between the first land and the second land.

Claims (1)

[Scope of Claims] 1. A valve hole in which an import port to which line pressure is supplied, an out port that communicates with the shift valve via the throttle valve when the throttle opening is equal to or greater than a predetermined value, and a drain port are opened; and the valve hole. A spring disposed in the valve hole is slidably inserted into the valve hole, and a hydraulic pressure of the out port is applied to balance the biasing force exerted on one side by the hydraulic pressure and the biasing force exerted on the other side by the spring. a spool that is displaced by a first land that opens and closes the input port to the out port according to the displacement of the spool; A hydraulic control circuit for an automatic transmission for a vehicle, comprising: a second land that fits into an inner circumferential wall to always close the drain port and increases or decreases the fitting length according to displacement of the spool. constant pressure valve.