JPS581307B2 - Pressure regulating device depending on the adjustment amount of the output regulating mechanism, especially for hydraulic switching devices of load conversion mechanisms in automobiles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pressure regulating device for a hydraulic switching device of a load conversion mechanism, in particular in a motor vehicle, which is dependent on the regulation amount of a power regulating mechanism.

Load converters of this type usually consist of a planetary gear set shifted by clutches and brakes and an upstream torque converter.

In order to actuate the switching elements (clutches and brakes), a pressure is required in the switching device that increases with the torque of the engine upstream of the load conversion mechanism.

In addition, this load-dependent pressure, together with the travel speed-dependent pressure, serves to determine the position of the automatic switching point.

A switching device of this kind, which includes a throttle pressure valve regulated by the accelerator pedal and acting as a pressure reducing valve, is disclosed in German Patent Publication No. 1 780 067.
See publication.

For example, a cam turned by a throttle control rod acts on the regulating piston of this throttle pressure valve, so that a load-dependent pressure is generated in the line system of the pressure regulating valve connected to the clutch damper and the switching valve. There is.

In addition to this, the pressure corresponding to this load is
It acts on the piston of the main pressure valve, which determines the main pressure in the switching device, so that the pressure in the switching element is also controlled depending on the load.

However, the demands on the pressure generated by the pressure regulating valve are opposite with respect to the transmission.

On the one hand, this means that the switching element should be loaded with a variable pressure that corresponds to a course similar to the torque curve of the engine.

This means that the pressure increase should occur as steeply as possible in the lower load region and should remain constant in the upper load region.

However, on the other hand, the switching point position, which is determined by the pressure as a function of load and vehicle speed, changes very little in the lower load range and significantly in the upper load range for reasons of ride comfort and fuel consumption. It should be.

In order for this to be achieved, the design must be such that the pressure increases gradually.

In the switching device described, only one load-dependent pressure can be used which is tuned to the desired switching point characteristic.

This load-dependent pressure setting takes place by means of a cam acting on the adjusting piston.

That is, the spring in contact with the pressure regulating piston is more or less tensioned by the regulating piston, and the regulating piston thus generates a pressure in the pressure reducing valve according to the initial tension of the spring.

This pressure regulating device, which is tuned to the switching point characteristic, therefore does not allow the pressure in the switching element to follow rapidly as the engine load increases.

The purpose of the invention is to generate, in addition to the load-dependent pressure synchronized to the automatic switching point conventionally practiced up to now, another load-dependent pressure whose rise is adapted to the engine torque changes. There is a pressure regulator to be obtained.

This object is achieved according to the invention by the features described in the claims.

This rapidly increasing throttling pressure serves on the one hand for the control of the main pressure valve and for the control of the main pressure in the sense of a steep pressure rise in the switching element, and on the other hand for the control of the damper subordinate to the switching element. useful for.

Thanks to the pressure regulating device according to the invention, the switching element is provided with an optimum transmission pressure for a reliable switching transition without interruption of the tractive force at any engine load.

Embodiments of the present invention will be described in detail below with reference to the drawings.

As shown in FIGS. 1 to 3, the switching device includes an oil pump P driven by an automobile engine and a main pressure valve 10.
, a converter pressure valve 20, a selection valve 30, a throttle pressure valve 40 dependent on the accelerator pedal and two stop valves 50 and 60.

The stop valve 50 is subordinated to the 2-3 switching valve 90, and the stop valve 60
is subordinated to the 1-2 switching valve 70.

The speed governor R generates a pressure dependent on the running speed which is guided via the conduit 240 onto the end faces 73 and 93 of the switching valve 70 or 90 for automatic speed switching.

A throttle pressure valve 40 is used to control the governor pressure according to the traveling speed.
The load-dependent throttling pressure produced by the piston surface 90A, 90B, 70B or 70A of the diverter valves 90 and 70 reacts via the line system 220 or 221.

The governor pressure depending on the running speed and the throttle pressure depending on the load determine the position of the automatic switching point.

The switching valves 70 and 90 distribute pressure oil to the clutch K2 and the brakes B1, B1F and B2 depending on their position at the left or right stop.

Clutch K1, which has been switched to all forward speed stages, is directly controlled via selection valve 30.

A pressure regulating valve 110 and a damper 120 whose piston 121 can be shifted against the force of a spring 122 in a damper space 123 are subordinated to the clutch K2, whereas the brake B1F has a pressure regulating valve 150, and a damper 160 consisting of a piston 161, a spring 162 and a space 163.

The pressure regulating valve and the damper serve to ensure a gradual pressure build-up corresponding to the clutch torque within the shortest possible time, so that gear changes can occur quickly and without shocks.

The oil pump P takes pressure oil from the tank S and delivers it via line 202 to the main pressure valve 10 in the main pressure line 205, which regulates the so-called system pressure or main pressure.

If the delivery amount is excessive, the slider 10 of the main pressure valve 10
A control collar 18 formed at A opens a flow path through the cooler K to a passage 28 that communicates with the torque converter W and the converter pressure valve 20.

Converter pressure valve 20 has a control piston 20A with control collars 21 and 22.

This control piston 20A is pushed to the right by a spring 27A which is supported by the main pressure valve 10.

This spring 27A is reacted by the pressure of the oil flowing out through the passage 28A towards the converter W which loads the control collar 22.

Excess oil is returned to the tank S through a passage 28 connected to the air vent groove 23 by a control collar 21 so that the pressure in the converter W is limited to a certain maximum value.

When the discharge amount by the pump P is increased, the slider 10A of the main pressure valve 10 moves further to the right against the force of the spring 27A and the force of the spring 27B, which acts only on the slider and is supported by the valve box. Shifted.

This takes place by loading the differential surface 13A formed in the control collar 13 and in which the annular space 14 is connected via the channel 204 to the conduit 202.

At this time, the control collar 15 allows the return passage 2 to pass through the conduit 202.
Since the communication to 03 is released, the oil not consumed by the converter W and the switching device can flow away towards the tank S.

The selection valve 30 has the following switching positions: “P” Park; “R” Reverse; “N” Idle (neutral); “A” Automatic (driving position); “2” 1st and 2nd gear. It is possible to drive only in automatic "1" first gear, which is limited to .

In the switching position "A" of the selection valve 30, the main pressure line 20
5 passes through the passage 207 to the piston surface 1 of the slider 10A.
1 is connected to an annular space 12 which projects into the interior.

This piston surface 11 is thus switched into a differential surface 13A, so that a larger cross section is released from the control collar 15 towards the return passage 203.

This initially causes the pressure in main pressure conduit 205 to drop.

As soon as the driver blows fuel, throttling pressure is introduced into the space 26 of the main pressure valve 10 via the passage 222.

At this time, this pressure acts on the piston surface 18A of the control collar 18 and supports the forces of the springs 27A, 27B.

The force acting on piston surface 18A balances slider 10A against the pressure on piston surfaces 11 and 13A.

That is, the control collar 15 of the slider 10A is connected to the return path 2.
03 must be established by the pump P to keep it open.

This pressure, which depends on the magnitude of the throttling pressure introduced through passage 222, is used as the main pressure in conduit 205.

As the throttling pressure increases, the main pressure at the switching member also increases.

In position A of the selection valve 30, the main pressure conduit 205 is
1st speed clutch K via conduits 208A and 208B
1 is connected to the supply conduit 208.

Therefore, when fuel is blown, the clutch K1 acts as a starting clutch.

In addition, main pressure is supplied to the governor R via the conduit 208A.

When the vehicle speed reaches a speed such that the governor pressure in conduit 240, which is dependent on road speed, can shift the switching valve 70 towards the right, pressure oil is transferred from the supply conduit 208 to the pressure regulating valve 150. It then flows into a supply passage 214 communicating with brake B1F.

Note that the supply passage 214 is connected to the annular space 1 of the pressure regulating valve 150.
56, is connected to the 2-3 switching valve 90 on the left through another supply passage 177, and is connected to the brake B1 through the supply passage 216.
connected to.

The pressure regulating valve 150 first ensures rapid filling of the brake B1F, and then the pressure rises relatively slowly to the closing pressure required for torque transmission.

During this closing phase, the piston 161 resists the swell pressure introduced into the damper space 163 via the throttle pressure conduit 222 until it is finally able to move the pressure regulating valve 150 towards the left. Then, only that braking stroke will proceed, so
Full mains pressure is present in the brake via the supply channel 214.

This measure allows flexible and rapid load switching.

In switching position A, in third gear the governor pressure in conduit 240 is so high that switching valve 90 is also shifted towards the right.

In addition to the line connections already made in the second gear from the main pressure line 205 to the clutch K1 and the brake B1F, there is now from the supply line 208 the 1 shifted towards the right.
Via the -2 switching valve 70, the channel 213, the 2-3 switching valve 90 moved to the right and the supply channel 215, another line connection is made to the pressure regulating valve 110 and the clutch K2.

At this time, the pressure configuration in clutch K2 is controlled by pressure regulating valve 110 and damper 120.

The brake B1 is connected to the air vent groove 104 via the supply passage 216 and the 2-3 switching valve 90 moved toward the right.

In switching position "2", the pressure line 2 is closed by the stop valve 50.
31, the pressure reduced with respect to the main pressure is transferred to the switching valve 9.
Guided to 0A.

In this case, only the two lower gears are automatically shifted.

In the switching position "1", in the same way, the stop valve 60
As a result of the pressure regulated by and led via the pressure line 236 to the piston face 70A of the switching valve 70, this switching valve is blocked by the left stop in that position and no switching takes place.

In addition, in this switching position, the brake B2 is communicated with the main pressure conduit 205 via the supply passage 146, the 1-2 switching valve 70, and the passage 209.

By applying the brake B2, a desired braking effect can be obtained when driving on a downhill section.

The pressure regulating device according to the present invention comprises a throttle pressure valve 40 and a modulating valve 340, as shown in FIG.

A passage 206 branching off from the main pressure conduit 205 is connected to the annular space 46 of the throttle pressure valve 40 and the annular space 341 of the modulating valve 340 .

These two valves 40 and 340 similarly operate as pressure reducing valves for the main pressure.

The throttle pressure valve 40 has a valve slider 41 and an adjusting piston 4
2, and a spring 43 is inserted between them.

A pressure PSD1 corresponding to the initial tension of the spring 43 in the passage 48
happens.

A cam N connected to the throttle control rod shifts the adjusting piston 42 to the right with increasing load on the drive engine.

This increases the initial tension and pressure PSD1 of the spring 43.

The notch 42A in the adjusting piston 42 is connected to the conduit system 22.
0 or 221, a pressure PSD1 is supplied to the switching valve 90 straddle 70, which together with the pressure of the governor R acting in the conduit 240 determines the position of the automatic switching point.

Modulating valve 340 has an adjusting piston 342 supported by a valve slider 344 via a spring 343.

The piston surface 345 of the adjusting piston 342 receives, via the passage 48, the pressure PSD1 created by the throttle pressure valve.

Adjusting piston 342 tensions spring 343 depending on the magnitude of pressure PSD1.

At this time, another pressure P is generated on the end face 346 of the valve slider 344.
SD2 is configured.

The ratio of pressure PSD2 to pressure PSD1 is the end area 346
equal to the ratio of 345 to

The stroke of piston 342 is limited by stopper 347.

The magnitude of the pressure PSD2 in the throttle pressure conduit 222 is therefore also limited.

The diagram shown in FIG. 5 shows the throttle pressure valve 40 in solid line.
2 shows the pressure PSD1 generated in the passageway 48 and in the conduit system 220, 221 by.

The dashed line, on the other hand, shows a steeper course of the throttle pressure PSD2, which remains constant after the shift stroke of the adjusting piston 342 has ended.

The characteristic line of spring 343 determines the maximum value of PSD2,
The ratio of area 345 to area 346 determines angle α.

Throttle pressure PSD2 acts on piston surface 18A in space 26 of main pressure valve 10 via throttle pressure conduit 222;
Push the control collar 15 in the closing direction with respect to the return passage 203.

The pump P now acts on the differential surface 13A and the piston surface 11 and constitutes a suitable main pressure that balances the slider 10A and forces the excess oil flow away towards the return passage.

That is, the pressure characteristic obtained by the pressure regulating device 40, 340 according to the invention is transmitted on its side to the main pressure valve 10, which controls the corresponding course of the main pressure in the switching element.

In order to adapt to the sudden increase in the drive torque at the switching element, the throttle pressure PSD2 is also introduced into the damper space 123 or 163, so that the pressure regulating valve 110 or 150 modifies the clutch pressure corresponding to the respective clutch torque during the switching process. .

FIG. 4 shows another embodiment of the pressure regulating device according to the invention with a restriction device separate from the modulating valve.

A passage 206 communicating with the main pressure conduit 205 leads not only to the throttle pressure valve 40 but also to a modulation valve 350 with a valve slide 351 .

The piston surface 352 of the valve slide 351 is loaded via the passage 48 with a pressure PSD1.

At the same time, a pressure PSD3 is created on the differential surface 355 formed by the control collars 353 and 354, the effect of which is balanced by the effect of the pressure PSD1 on the larger piston surface 352.

The pressure PSD3 is proportional to the loaded surfaces 352 and 355, thus resulting in a pressure increase corresponding to the dashed line in FIG.

Pressure PSD3 is supplied via passage 356 to piston face 358 of restriction valve 357 which is pushed to the right by spring 359.

If the force consisting of the product of pressure PSD3 and the area of piston surface 358 is less than the initial tension of spring 359, then PSD
3 acts directly on the main pressure valve 10 and dampers 120 and 160 via the throttle pressure conduit 222A.

When the force of pressure PSD3 on piston surface 358 becomes greater than the initial tension of spring 359, valve 357 closes control edge 36.
0 makes communication to the air vent groove 361.

Thus, subsequent pressure build-up is limited.

That is, the pressure PSD3 is kept constant (FIG. 5).

The height of the pressure that can be reached depends in this case on the respective selected initial tension of the spring 359.

By changing the initial tension of the differential surface 355 and the spring 359, an arbitrary pressure characteristic line can be obtained.

However, the lower limit is determined by the pressure PSD1, and the upper limit is determined by the main pressure.

In this case, the design is carried out according to the characteristic curve of the engine.

A check valve 362 is incorporated between passageway 356 and throttle pressure conduit 222A for pressure equalization purposes.

Embodiments according to the present invention are summarized below.

1) devices 347, 357 are provided for limiting the rapidly increasing throttle pressure (PSD2:PSD3) to a maximum value;
A pressure regulating device according to the claims.

2) Valve slider 344 on which modulating valve 340 controls the main pressure
, and an adjusting piston 342 which is loaded by a load-dependent pressure PSD1 and is spring-loaded against the valve slider, the adjusting stroke of which is limited by a stop 347.
The scope of the claims and the preceding paragraph 1
).

3) The pressure regulating device according to the claims and the preceding clause 1), which is provided with a restriction valve 357 separated from the modulating valve 352.

4) Modulated throttling pressure applied by the load-dependent pressure PSD1 on the one hand and supplied by the control edge 360 via the piston differential surface 355 to a limiting valve 357 loaded by a spring 359 and having an air vent groove 361; The pressure regulating device according to the claims and item 1), wherein the modulating valve 350 is configured to have a valve slider 351 loaded by the PSD 3.

5) Restriction valve 357 leading to passage 356 and main pressure valve 10
The pressure regulating device according to item 3), wherein a check valve 362 is incorporated between the throttle pressure conduit 222A and the pressure regulating device.

[Brief explanation of drawings]

1 shows a part of a hydraulic switching device with a pressure regulator according to the invention, FIGS. 2 and 3 are complete circuit diagrams of the hydraulic switching device in neutral position, and FIG. 4 shows a pressure regulator according to the invention. FIG. 5, which shows a further embodiment of the regulating device, shows a diagram of various pressure characteristic lines obtained by the pressure regulating device according to the invention. 10... Main pressure valve, 20... Converter pressure valve, 30... Selection valve, 40...
Throttle pressure valve, 42,342...adjustment piston,
50, 60...Stop valve, 70...1-
2 switching valve, 90...2-3 switching valve, 110,1
50...Pressure regulating valve, 120, 160...
...Damper, 123,163...Danha space,
222, 222A... Conduit, 340, 350.
...Modulation valve, 357...Restriction valve, 362
... Check valve, PSD1 ... Load-dependent pressure, PSD2, PSD3 ... Throttle pressure that rises rapidly in the lower load region of the engine, P ...
・・Oil pump, R・・・・Governor, S・・・・
Oil tank, K... Cooler, K1, K2...
...Clutch, W...Converter.

Claims (1)

[Claims] 1 A main pressure valve that is connected to the pressure pump and generates the main pressure that acts on the switching member (clutch and brake), which is connected to the main pressure valve and is operated according to the output adjustment mechanism, and which is operated according to the load by the output adjustment mechanism. Power regulation of an engine, especially for hydraulic switching devices of load conversion systems in motor vehicles, consisting of a throttle pressure valve that generates a pressure and, together with this pressure, provides a load-dependent pressure that controls the position of the switching point for gear shifting. In a pressure regulating device that depends on the adjustment amount of the mechanism, it is connected to the throttle pressure valve, is loaded by the main pressure, is regulated according to the pressure according to the load (PSD1), and increases in the lower part of the engine load range. A modulating valve 340, 350 is provided which generates a pressure which increases with the load and is approximately constant in the rest of the load range, and which is connected via the conduit 222; 222A to the space 26 of the main pressure valve 10 as well as to the damper. space 12
3; 163; a pressure regulating device characterized in that the pressure generated by the modulating valve is applied to the piston surface 18A of the main pressure valve 10 and the damper space to regulate the pressure;