JP3498476B2 - Hydraulic control valve - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control valve for controlling hydraulic pressure, and more particularly to a hydraulic control valve for controlling hydraulic pressure of a friction engagement device involved in clutch-to-clutch shift in an automatic transmission. is there.

[0002]

2. Description of the Related Art A clutch-to-clutch shift in an automatic transmission is a shift performed by simultaneously switching the engaged / released states of two friction engagement devices such as a multi-disc clutch and a multi-disc brake. This is a form of gear shifting that occurs when the one-way clutch is eliminated. Therefore, one of the friction engagement devices ideally needs to operate similarly to the one-way clutch, and various techniques have been developed for that purpose.

For example, an automatic transmission described in Japanese Patent Laid-Open No. 6-341525 discloses a 5-speed automatic transmission in which a main transmission unit capable of setting four forward gears and one reverse gear is connected in series with an overdrive unit. The second forward speed of the machine is set by a multi-disc clutch and a multi-disc brake instead of the one-way clutch in the main transmission unit. Therefore, the shift between the second speed and the third speed is performed by a clutch toe, which simultaneously switches the engagement / release states of the two friction engagement devices (specifically, the second brake and the third brake). It will be clutch shift.

When the automatic transmission shifts up, for example, from the second speed to the third speed, after the shift control is started, the hydraulic pressure of the friction engagement device on the release side is gradually reduced, and the friction engagement is started at the same time when the inertia phase is started. It is necessary to release the compounding device. Therefore, in the above-described conventional automatic transmission, a control valve for controlling the hydraulic pressure of the friction engagement device on the release side is provided, and the hydraulic pressure of the friction engagement device on the engagement side is supplied to this control valve as a signal pressure for engagement. The release pressure of the disengagement side frictional engagement device is controlled according to the hydraulic pressure of the side frictional engagement device.

To explain this concretely, FIG. 5 shows a 2-3 timing valve 70 described in the above publication. This 2-3 timing valve 70 has a small diameter land and two large diameter lands. A spool 71 forming a land, and a first
Of the plunger 72, a spring 73 arranged between them, and a second plunger 74 arranged on the opposite side of the first plunger 72 with the spool 71 in between. An oil passage 76 is connected to an intermediate port 75 of the 2-3 timing valve 70, and this oil passage 76 is connected to the third brake B3 via a 2-3 shift valve (not shown).

Further, the oil passage 76 is branched on the way and is connected to a feedback port 77 opened between the small diameter land and the large diameter land through an orifice.
The port 78 selectively connected to the intermediate port 75 is connected to the oil passage 79 via a solenoid relay.
It is connected to shift valves (not shown) to control the drain speed from the third brake.

A control port 80 for applying a hydraulic pressure to the upper plunger 74 in FIG. 5 is formed, and an oil passage 81 is connected to the control port 80. The oil passage 81 is an oil passage to which the third speed pressure (the hydraulic pressure output when the third speed is set) is supplied via the 2-3 shift valve when the third speed is set, and the orifice is provided in the middle thereof. 82 and an orifice 83 with a check ball in parallel therewith are provided,
It branches off downstream of these orifices 82 and 83 in the hydraulic pressure supply direction and is connected to the control port 80. An accumulator 84 is connected to the other branched oil passage. Therefore, the upper control port 80 in FIG.
Is supplied with the hydraulic pressure of the second brake B2 as a signal pressure.

A control port 85 for applying hydraulic pressure to the end of the 2-3 timing valve 70 opposite to the control port 80, that is, the lower plunger 72 in FIG. 5, is formed. A linear solenoid valve SLU is connected to the port 85, and a signal pressure according to the duty ratio is applied to the control port 85.

The face area on which the feedback pressure acts in the above-mentioned 2-3 timing valve 70 is different between the upper and lower sides as shown in FIG. 5, and the pressure should be discharged from the third brake B3 in order to set the third speed. When the hydraulic pressure of the third brake B3 is applied to the spool 71, the spool 71 is pressed downward in FIG. 5, and the port 75 communicates with the drain port 86. As a result, the hydraulic pressure that presses the spool 71 downward is not applied, so that the spool 71 is pushed up by the spring 73 and the port 75 communicates with the port 78. In this way, the feedback pressure and the elastic force of the spring 73 oppose each other to adjust the pressure.

In addition to this, the upper control port 8 in FIG.
Since the hydraulic pressure of the second brake B2 is supplied to 0 and the signal pressure of the linear solenoid valve SLU is supplied to the lower control port 85, the differential pressure of the signal pressure acting on these control ports 80 and 85 is , The elastic force of the spring 73 determines the pressure regulation value.

Therefore, when hydraulic pressure starts to be supplied to the second brake B2 during the upshift from the second speed to the third speed,
Initially, the hydraulic pressure is low, so the pressure adjustment value is set to a high value, and as a result, the release pressure of the third brake B3 is maintained high. Then, when the piston for engaging the second brake B2 reaches the stroke end (when the pack clearance is clogged), the hydraulic pressure of the second brake B2 starts to increase greatly, and the pressure of the timing valve 70 is adjusted accordingly. Since the value decreases, the release pressure of the third brake B3 starts to decrease. In this way, the third friction engagement device on the release side is used.
The release pressure of the brake B3 is adjusted by the hydraulic pressure of the second brake B2, which is the friction engagement device on the engagement side, and the timing of engagement and release of both friction engagement devices is adjusted.

[0012]

A friction engagement device in a general automatic transmission controls engagement / disengagement by a piston operated by hydraulic pressure. However, the hydraulic pressure at the piston portion is directly controlled. It is actually impossible to detect it due to the structure of the automatic transmission. Therefore, as described above, the oil passage leading to the friction engagement device is branched midway, and the hydraulic pressure at that portion is divided by the friction engagement device. The signal pressure for control is used instead of the hydraulic pressure. Therefore, in the above example, the control port 80 which uses the hydraulic pressure of the second brake B2
Since there is a flow resistance in the oil passage from the control port 80 to the second brake B2 between the hydraulic pressure in the second brake B2 and the hydraulic pressure in the second brake B2, the pack clearance of the second brake B2 is not blocked, that is, the piston is When the oil is still moving and there is a flow of oil, a differential pressure is generated due to the flow resistance.

More specifically, the hydraulic pressure is supplied to the second brake B2 from the orifice 82 side in FIG. 5, and the hydraulic pressure acts on the control port 80 on the downstream side of the orifice 82. On the other hand, the second brake B2 is supplied with oil by further flowing through the oil passage from the orifice 82, and the flow resistance during that causes a decrease in hydraulic pressure. Therefore, as shown in FIG. 6, the hydraulic pressure at the control port 80 is the pressure shown by the broken line, but the actual hydraulic pressure at the second brake B2 is the pressure shown by the solid line at a lower pressure than that. In accordance with this, the hydraulic pressure PB3 of the third brake B3
Should be set to the hydraulic pressure indicated by the solid line corresponding to the actual hydraulic pressure of the second brake B2, but since the pressure adjustment value is determined by the hydraulic pressure indicated by the broken line of the second brake B2, it is controlled to the low pressure indicated by the broken line.

While the hydraulic pressure for engaging the second brake B2 is flowing, there is a difference between the pressure detected for control and the actual hydraulic pressure at the second brake B2. Is caused by the fluctuation of the conduit resistance and the source pressure as described above. Therefore, when the oil viscosity changes according to the oil temperature or the source pressure (line pressure) changes according to the throttle opening, the difference between the signal pressure for control and the oil pressure at the second brake B2. Pressure ΔPB2 fluctuates. That is, this differential pressure ΔPB2 does not become a constant value, but changes depending on the condition of the vehicle. As a result, the release pressure control characteristic of the release side third brake B3 is disturbed, and both brakes are disturbed. B2 and B3 both have torque capacities above a certain level and output torque decreases, or conversely, the torque capacities of both brakes B2 and B3 decrease and engine overshoot occurs. There was a possibility.

The present invention has been made in view of the above circumstances, and controls the hydraulic pressures of two friction engagement devices for executing clutch-to-clutch shifts in a mutually related manner without receiving a disturbance. It is an object of the present invention to provide a hydraulic control valve that can be operated.

[0016]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention sets the engagement pressure of an engagement side friction engagement device at a predetermined gear shift in an automatic transmission to a signal pressure. by setting the pressure value by acting as, in the hydraulic control valve pressure regulating the release pressure of the release side frictional engagement device, wherein
The port that guides the release pressure to the drain and the release pressure
As the feedback pressure increases, the port is opened.
The spool that moves to the
Spring located at the point where the feedback pressure acts
The spring between it and the end of the spool.
Plunger placed in a crowded state and its plunger
The engaging pressure to push the spring to the spring side.
Control port and the plan that sandwiches the spool
The other plunger located on the opposite side of the
Is it a solenoid valve that presses the plunger toward the spool side?
And another control port for applying a signal pressure from
The pressing force of the plunger due to the engagement pressure is the spring.
In the state below the pressure based on the elastic force of
Pressure is adjusted based on the elastic force of the pulling and
The pressing force of the plunger due to the combined pressure of the spring
In the state larger than the pressure based on the elastic force,
It is configured to adjust the pressure based on the engagement pressure.
It is characterized in that that. The elastic force of the pre-Symbol springs, as are described in claim 2, push the plunger by the engagement pressure between up to the engagement side frictional engagement device starts waiting a predetermined torque capacity It can be set below the pressure.

Therefore, the hydraulic control valve of the present invention controls the hydraulic pressure at the time of so-called clutch-to-clutch shift, and is a signal pressure until the hydraulic pressure of the engagement side friction engagement device rises to a predetermined value. The combined pressure does not affect the regulated value for controlling the release pressure . That is, before the engagement pressure
Note that the pushing force of the plunger is less than the pushing force of the spring.
In the state, the spring will push the spool
Therefore, the engagement pressure does not affect the pressure regulation value. More concrete
Is the pressing force of the plunger due to the engagement pressure.
The signal pressure and sp
Adjusts the pressure based on the elastic force of the ring and
Based on the elastic force of the spring,
When the pressure is higher than the applied pressure, the signal pressure and the engagement pressure
The pressure is adjusted based on and. Conditions such as this is, is set to continue for (until pack clearance is clogged) to the stroke end of the piston in the engagement side frictional engagement device, the hydraulic pressure of the engagement side frictional engagement device So-called disturbances such as source pressure and oil flow resistance do not affect the pressure regulation value. When the hydraulic pressure of the engagement side frictional engagement device has increased to some extent, that is, after the piston reaches the stroke end, the hydraulic pressure of the engagement side frictional engagement device is reflected as it is in the pressure adjustment value. The hydraulic pressure of the side frictional engagement device is controlled according to the hydraulic pressure of the engagement side frictional engagement device.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an example in which the present invention is applied to the automatic transmission described in the above-mentioned JP-A-6-341525 will be described. Figure 2 is a total control system diagram, the engine E that is connected to the automatic transmission A has a slot Rubarubu 1 3 to the intake channel 12. As a
Depression of slot Rubarubu 13 accelerator pedal 1 5
Throttle actuator 1 such as a servomotor in accordance with the
It is designed to be opened and closed by 6.

[0019] controls the throttle actuator 16 to adjust the opening of this scan Rottorubaru Bed 13, also the engine electronic control unit for controlling the fuel injection amount and the ignition timing of the engine E (E-ECU) 17 are provided. The electronic control unit 17 is mainly composed of a central processing unit (CPU), a storage unit (RAM, ROM), and an input / output interface. The electronic control unit 17 stores data for control as Various signals such as engine (E / G) rotation speed N, intake air amount Q, intake air temperature, throttle opening, vehicle speed, engine water temperature, and signals from brake switches are input.

In the automatic transmission A, the hydraulic control device 18 controls gear shifting and lockup clutch, line pressure, or engagement pressure of a predetermined friction engagement device. The hydraulic control device 18 is configured to be electrically controlled, and also has first to third shift solenoid valves S1 to S3 for executing a shift and a first to third engine for controlling an engine braking state. 4 solenoid valve S4, linear solenoid valve SLT for controlling the line pressure, linear solenoid valve SLN for controlling the back pressure of the accumulator, linear for controlling the engagement pressure of the lockup clutch and a predetermined friction engagement device A solenoid valve SLU is provided.

An electronic control unit (T-ECU) 19 for an automatic transmission that outputs signals to these solenoid valves to control gear shift, line pressure, accumulator back pressure, etc.
Is provided. This automatic transmission electronic control unit 19
Is a central processing unit (CPU) and a storage device (RA
M, ROM) and an input / output interface, and this electronic control unit 19 indicates throttle opening, vehicle speed, engine water temperature, signals from brake switch, and shift position as data for control. Signal, signal from pattern select switch, signal from overdrive switch, clutch C described later
A signal from a C0 sensor that detects the rotational speed of 0, an oil temperature of the automatic transmission, a signal from a manual shift switch, and the like are input.

The electronic control unit 19 for the automatic transmission and the electronic control unit 17 for the engine are connected to each other so that data can be communicated with each other, and the electronic control unit 17 for the engine transfers to the electronic control unit 19 for the automatic transmission. On the other hand, a signal such as the intake air amount per rotation (Q / N) is transmitted, and an instruction signal for each solenoid valve is sent from the automatic transmission electronic control unit 19 to the engine electronic control unit 17. A signal equivalent to, a signal instructing a shift speed, and the like are transmitted.

That is, the electronic control unit 19 for the automatic transmission
Is based on the input data and the map stored in advance, and the ON / OFF of the gear position and the lockup clutch is performed.
F, or the line pressure or the adjustment level of the engagement pressure is judged, and based on the judgment result, an instruction signal is output to a predetermined solenoid valve, and further judgment of fail or control based on it is performed. . The engine electronic control unit 17 based on the input data walk fuel injection amount and the ignition timing in addition to controlling the opening degree of the scan Rottorubaru Bed 13, fuel injection during a shift in the automatic transmission A reducing the amount or changing the ignition timing, Moshiku by narrowing the opening degree of the scan b <br/> Ttorubaru Bed 13, it has an output torque so as to temporarily decrease.

FIG. 3 is a diagram showing an example of a gear train of the above-mentioned automatic transmission A, and in the configuration shown here, it is configured to set five forward gears and one reverse gear. That is, the automatic transmission A shown here is used in the torque converter 20.
And a sub-transmission unit 21 and a main transmission unit 22. The torque converter 20 includes a lockup clutch 23.
The lock-up clutch 23 has a front cover 25 that is integrated with the pump impeller 24.
A member (hub) in which the turbine runner 26 and the turbine runner 26 are integrally attached
It is provided between 7 and. An engine crankshaft (not shown) is connected to a front cover 25, and a turbine runner 26 is connected to an input shaft 28.
Is connected to a carrier 30 of an overdrive planetary gear mechanism 29 that constitutes the subtransmission unit 21.

The carrier 3 in this planetary gear mechanism 29
A multi-plate clutch C0 and a one-way clutch F0 are provided between 0 and the sun gear 31. The one-way clutch F0 is engaged when the sun gear 31 rotates forward relative to the carrier 30 (rotates in the rotation direction of the input shaft 28). Further, a multi-plate brake B0 for selectively stopping the rotation of the sun gear 31 is provided.
The ring gear 3 which is an output element of the subtransmission unit 21
2 is connected to an intermediate shaft 33 which is an input element of the main transmission unit 22.

Therefore, in the subtransmission unit 21, the entire planetary gear mechanism 29 rotates integrally when the multi-plate clutch C0 or the one-way clutch F0 is engaged, so that the intermediate shaft 33 has the same speed as the input shaft 28. It will rotate at low speed. Further, in the state where the brake B0 is engaged and the rotation of the sun gear 31 is stopped, the ring gear 32 is accelerated with respect to the input shaft 28 to rotate in the normal direction, and the high speed stage is established.

On the other hand, the main transmission unit 22 is provided with three sets of planetary gear mechanisms 40, 50, 60, and their rotating elements are connected as follows. That is, the sun gear 41 of the first planetary gear mechanism 40 and the sun gear 51 of the second planetary gear mechanism 50 are integrally connected to each other, and the ring gear 43 of the first planetary gear mechanism 40 and the carrier 52 of the second planetary gear mechanism 50 are connected. The third planetary gear mechanism 60 and a carrier 62 are coupled to each other, and the carrier 62 is coupled to an output shaft 65. Further, the ring gear 53 of the second planetary gear mechanism 50 is connected to the sun gear 61 of the third planetary gear mechanism 60.

In the gear train of the main transmission unit 22, it is possible to set a reverse gear and four gears on the forward side, and clutches and brakes therefor are provided as follows. First, the clutch will be described. The ring gear 53 and the third gear of the second planetary gear mechanism 50 which are connected to each other.
A first clutch C1 is provided between the sun gear 61 of the planetary gear mechanism 60 and the intermediate shaft 33, and the sun gear 41 of the first planetary gear mechanism 40 and the sun gear 51 and the intermediate shaft of the second planetary gear mechanism 50 are connected to each other. A second clutch C2 is provided between the first clutch 33 and the second clutch C3.

Next, the brake will be described. The first brake B1 is a band brake, and the sun gears 41, 5 of the first planetary gear mechanism 40 and the second planetary gear mechanism 50.
It is arranged to stop the rotation of 1. A first one-way clutch F1 and a second brake B2, which is a multi-disc brake, are arranged in series between the sun gears 41 and 51 (that is, the common sun gear shaft) and the casing 66. One way clutch F1 is sun gear 41,5
1 engages when trying to rotate in the reverse direction (rotation in the direction opposite to the rotation direction of the input shaft 28).

A third brake B3, which is a multi-plate brake, is provided between the carrier 42 of the first planetary gear mechanism 40 and the casing 66. Then, as a brake for stopping the rotation of the ring gear 63 of the third planetary gear mechanism 60, a fourth brake B4, which is a multi-disc brake, and a second one-way clutch F2.
And are arranged in parallel with the casing 66. The second one-way clutch F2 is adapted to be engaged when the ring gear 63 tries to rotate in the reverse direction.

In the above-described automatic transmission A, it is possible to set five forward speeds and one reverse speed by engaging and disengaging each clutch and brake as shown in the operation table of FIG. In FIG. 4, a circle indicates an engaged state, a circle indicates an engaged state during engine braking, a triangle indicates either engaged or disengaged, and a blank indicates a disengaged state.

Therefore, the above automatic transmission A is a clutch-to-clutch that shifts between the second speed B3 and the third speed B3 when shifting between the second speed and the third speed. When the gear shifts, for example, when the second gear is upshifted to the third gear, the third brake B3 engaged at the second gear, which is the lower gear, is released at the same time as the start of the inertia phase. First, it is necessary to perform control in accordance with the engagement of the second brake B2 that sets the third speed, which is the higher gear.

FIG. 1 schematically shows a control valve therefor. The valve shown here is a pressure regulating valve called a B-3 control valve, in which a spool 1 having two lands is sandwiched. The two plungers 2 and 3 are arranged on the same axis. A first control port 4 for operating the signal pressure PSLU of the linear solenoid valve SLU is formed on the end side of the upper plunger 2 in FIG. 1, and a first control port 4 is formed on the other end side of the other plunger 3. A second control port 5 is formed for actuating the hydraulic pressure PB2 of the two brake B2. A spring 6 is arranged between the spool 3 and the plunger 3 on which the hydraulic pressure PB2 of the second brake B2 acts.

An input port 7 and an output port 8 opened between two lands on the spool 1 are formed. The input port 7 has a D range pressure (drive (D) range at the second forward speed). The hydraulic pressure output at is input. The output port 8 is connected to the third brake B3 via a solenoid relay valve (not shown).

Further, an open feedback port 9 is formed between the spool 1 and the lower plunger 3 in FIG. 1, and the feedback port 9 and the output port 8 are communicated via an orifice 10. . Further, a drain port 11 which is selectively opened and closed by the spool 1 is formed on the side opposite to the feedback port 9 across the output port 8.

Therefore, this B-3 control valve is a linear solenoid valve when the pressing force of the plunger 3 by the second brake pressure PB2 is less than the pressure based on the elastic force of the spring 6 (hereinafter, simply referred to as elastic force). S
Adjust the D range pressure to the pressure obtained by subtracting the elastic force of the spring 6 from the pressing force of the plunger 2 (the product of the signal pressure PSLU and the pressure receiving area of the plunger 2) by the LU, divided by the pressure receiving area of the feedback pressure. Output to the third brake B3. When the pressing force by the second brake pressure PB2 is larger than the elastic force of the spring 6, the linear solenoid valve SLU presses the plunger 2 (the product of the signal pressure PSLU and the pressure receiving area of the plunger 2) to the second brake pressure. PB2
The value obtained by subtracting the pressing force (the product of the second brake pressure PB2 and the pressure receiving area of the plunger 3) due to is divided by the pressure receiving area of the feedback pressure to adjust the D range pressure and output to the third brake B3. .

The elastic force of the spring 6 is applied to the second brake B2 until the second brake B2 starts to have a predetermined torque capacity (that is, until the piston engaging the second brake B2 reaches the stroke end). Pressure P
It is set below the pressing force by B2.

Next, the operation of the B-3 control valve will be described by taking the case of upshifting from the second speed to the third speed as an example. When the upshift from the 2nd speed to the 3rd speed is determined and the shift signal is output, a signal is output to the shift solenoid valves S1 to S3 to turn these ON.
The / OFF state is switched and the signal pressure is sent to a predetermined shift valve (not shown). Along with that, the input port 7 of the B-3 control valve is switched from the state where the D range pressure at the second speed is supplied to the state where it is communicated with the drain, but this input port 7 is the lower side in FIG. Closed by the land of. Further, the hydraulic pressure for engaging the second brake B2 starts to be supplied to the second control port 5. Further, the first control port 4 is supplied with the signal pressure PSLU output from the linear solenoid valve SLU based on its duty ratio.

In this case, immediately after the shift control is started, the second
If the brake pressure PB2 is less than the elastic force of the spring 6,
The elastic force of the spring 6 and the signal pressure PSLU of the linear solenoid valve SLU act on the spool 1 in an axially opposed state, and the pressure difference causes the spool 1 to be pressed downward in FIG. ing. That is, this pressure difference is the pressure regulation value of the B-3 control valve.

Since the hydraulic pressure PB3 of the third brake B3 acts on the output port 8 and the feedback port 9, if the hydraulic pressure PB3 is equal to the pressure adjustment value, the spool 1 moves to the upper side in FIG. The drain port 11 opens. Therefore, the feedback pressure decreases, so that the spool 1 moves to the lower side of FIG. 1 and closes the drain port 11. In this way, the hydraulic pressure PB3 of the third brake B3 is applied to the signal pressure of the linear solenoid valve SLU and the spring 6
The pressure is regulated by the elastic force of. Therefore, although the oil pressure PB2 of the second brake B2 is supplied to the second control port 5, the oil pressure PB2 does not affect the pressure adjustment value, and therefore the oil viscosity and line pressure fluctuations are used to control the oil pressure of the third brake B3. Fluctuation due to so-called disturbance does not occur.

Even in this case, there is a pressure difference between the hydraulic pressure acting on the second control port 5 and the actual hydraulic pressure at the second brake B2, but the second brake pressure PB2 becomes the regulated value. With no effect, the actual differential pressure is always constant. That is, the release pressure of the third brake B3 is set to a pressure corresponding to the actual engagement pressure of the second brake B2 by setting the regulated value of the hydraulic pressure of the third brake B3 to a value that allows for the differential pressure. Can be set.

In the torque phase during the upshift from the second speed to the third speed, the hydraulic pressure PB3 of the third brake B3 is gradually decreased by gradually decreasing the duty ratio of the linear solenoid valve SLU.

When the hydraulic pressure is continuously supplied to the second brake B2 and its pressure PB2 increases and exceeds the elastic force of the spring 6, the lower plunger 3 in FIG. 1 compresses the spring 6 and rises, A load is applied to the spool 1 from the lower side of FIG. That is, in this state, the spool 1 is shown in FIG.
The force pressing from the lower side replaces the spring 6 with the second
It is based on the brake pressure PB2, and the regulated value is a value based on the pressure difference between the second brake pressure PB2 and the linear solenoid valve SLU.

As described above, the elastic force of the spring 6 is
Since the elastic force is equivalent to the second brake pressure PB2 generated after the piston of the second brake B2 reaches the stroke end, there is no difference between the hydraulic pressure acting on the second control port 5 and the hydraulic pressure at the second brake B2. In this state, the second brake pressure PB2 begins to affect the pressure regulation value. Therefore, the subsequent third brake pressure PB3 is controlled according to the second brake pressure PB2, and as a result, the upshift to the third speed is executed without causing tie-up or engine overshoot. Therefore, the second plunger 3, the second control port 5 and the spring 6 maintain a regulated pressure value constant when the engagement pressure of the engagement side friction engagement device of the present invention is equal to or less than a preset pressure, and When the combined pressure exceeds a preset pressure, it corresponds to a mechanism that changes the pressure adjustment value according to the engagement pressure.

The present invention can be applied to a hydraulic control valve intended for an automatic transmission provided with a gear train different from the above-mentioned automatic transmission, and therefore the second speed to the third speed can be improved. The hydraulic control valve is not limited to the hydraulic control valve used during the shift, but may be configured as another hydraulic control valve.

[0046]

As described above, according to the hydraulic control valve of the present invention , engagement is performed until the hydraulic pressure of the engagement side friction engagement device increases to a predetermined value during so-called clutch-to-clutch shifting. Pressure affects the regulated value to control the release pressure.
The elastic force of the spring and the signal pressure from the solenoid valve
The release pressure is adjusted by. If such a state is set to continue until the stroke end of the piston in the engagement side friction engagement device (until the pack clearance is closed), the oil pressure of the engagement side friction engagement device is reduced. So-called disturbances such as pressure and flow resistance of oil can be prevented. When the hydraulic pressure of the engagement side frictional engagement device has increased to some extent, that is, after the piston reaches the stroke end, the hydraulic pressure of the engagement side frictional engagement device is reflected as it is in the pressure adjustment value. The oil pressure of the side friction engagement device can be controlled according to the oil pressure of the engagement side friction engagement device. Therefore, if the hydraulic control valve of the present invention is used, clutch-to-clutch gear shifting can be executed without causing shock due to tie-up or engine overshoot.

[Brief description of drawings]

FIG. 1 is a sectional view schematically showing an example of the present invention.

FIG. 2 is a diagram schematically showing an overall control system of an automatic transmission that can use the hydraulic control valve of the present invention.

FIG. 3 is a skeleton diagram showing an example of a gear train of the automatic transmission.

FIG. 4 is a diagram showing an engagement operation table of a friction engagement device for setting each shift speed in the automatic transmission.

FIG. 5 is a diagram schematically showing a 2-3 timing valve described in JP-A-6-341525.

FIG. 6 is a diagram for explaining the differential pressure between the signal pressure based on the second brake pressure and the actual engagement pressure and the accompanying change in the hydraulic pressure of the third brake.

[Explanation of symbols]

1 spool A few plungers 4,5 Control port 6 spring B2 Second brake B3 3rd brake PB2 Second brake pressure PB3 3rd brake pressure

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasushi Nakamura 1 Toyota-cho, Toyota-shi, Aichi Toyota Motor Corporation (56) References JP-A-5-306760 (JP, A) JP-A-4- 151064 (JP, A) JP-A-6-341537 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) F16H 59/00-63/48

Claims (2)

(57) [Claims] 1. A disengagement side frictional engagement device is set by causing an engagement pressure of an engagement side frictional engagement device at the time of a predetermined gear shift in an automatic transmission to act as a signal pressure to set a pressure adjustment value. In a hydraulic control valve that regulates the release pressure, a port that guides the release pressure to the drain and a flap of the release pressure are provided.
Opening the port due to increased feedback pressure
And a spool that moves like
Sprinkles placed where feedback pressure acts
And its spring with the end of the spool.
Plunger and its plunge placed in the state
The engaging pressure to push the spring to the spring side.
The control port to be used and the plug between the spool
Other plunger arranged on the opposite side of the plunger, and
Solenoid valve to push the plunger of the spool side.
And another control port for applying a signal pressure from the plunger, the pressing force of the plunger due to the engagement pressure is
In the state below the pressure based on the elastic force of the
And the elastic force of the spring to regulate the pressure, and
The pressing force of the plunger due to the engagement pressure is
When the pressure is larger than the pressure based on the elastic force of
Pressure is adjusted based on the pressure and the engagement pressure.
The hydraulic control valve is characterized by 2. The elastic force of the spring is the engaging side.
Until the frictional engagement device starts waiting for the specified torque capacity
Set below the pressing force of the plunger due to the engagement pressure of
The hydraulic control valve according to claim 1, characterized in that it is.