JPH0477818B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a hydraulic control device for a vehicle automatic transmission, and particularly to operation control of a frictional engagement element. [Prior Art] An automatic transmission for a vehicle controlled by a hydraulic control device has a system that selectively engages or disengages predetermined components of the transmission with other components, and adjusts vehicle speed and throttle opening. Frictional engagement devices such as clutches and brakes are provided in order to achieve a speed change ratio according to vehicle running conditions such as output shaft torque, setting position of a speed selection device such as a select lever, etc. This frictional engagement device is normally engaged and released by a hydraulic servo consisting of a hydraulic cylinder, a piston fitted into the cylinder, and return biasing means for the piston. This hydraulic servo is connected to a hydraulic control mechanism (regulator valve) that uses an oil pump driven by the output shaft of the engine as a hydraulic pressure generation source, and is installed in the hydraulic control device to regulate the oil pump discharge pressure according to vehicle running conditions. etc.), the pressure oil is regulated to a predetermined pressure, and is then transferred to the friction engagement element via a manual valve linked to a speed selection device and a hydraulic switching valve such as a shift valve operated by input oil pressure corresponding to vehicle running conditions. Supplied upon engagement. Further, when the frictional engagement element is released, the pressure oil is discharged through these switching valves. The hydraulic oil supply and drainage path to this hydraulic servo is connected to the hydraulic pressure inside the hydraulic servo (hereinafter referred to as servo pressure).
In order to adjust the rise (pressure increase characteristic) and fall (pressure fall characteristic) of A freely fitted piston, a return spring, an accumulator provided with return biasing means such as application of back pressure, a check valve, and a throttle are appropriately interposed. By the way, it is generally necessary to engage the frictional engagement element more slowly than the disengagement, and the hydraulic servo mechanism adapts to the engagement of the frictional engagement element to adjust the capacity of the accumulator and its return bias. Since the return characteristics of the means and the flow resistance of the hydraulic oil up to the confluence of the hydraulic oil supply and drain path and the hydraulic oil supply and drain path of the hydraulic servo are set, the servo pressure and the hydraulic pressure in the accumulator (hereinafter referred to as the hydraulic pressure) are set. In the above-mentioned hydraulic servo mechanism, which is set so that the accumulator pressure is equal to As a result, when the piston of the accumulator stops at the end point, the frictional engagement element suddenly releases, resulting in a disadvantage that the shift shock becomes large. Under these circumstances, conventionally, a restrictor with a check valve was installed in the hydraulic oil supply and drain path of the accumulator to delay the discharge of hydraulic oil from the accumulator and to hasten the drop in servo pressure. , proposals have been made to reduce the shift shock when the frictional engagement element is released (for example, Japanese Patent Laid-Open No. 51-66968;
(See Publication No. 50615, Publication of Utility Model Application No. 56-66554). [Problems to be Solved by the Invention] However, with the above-mentioned technology, although the servo pressure is smoothly lowered when the frictional engagement element is released, it is difficult to ensure accurate release timing according to the driving conditions of the vehicle. It is. Furthermore, while the engagement operation of a friction engagement element is performed in a dynamic friction state (sliding engagement) in which the friction materials rub against each other, the release operation is performed in a static friction state in which the friction materials separate from the previously engaged contact state. Since the release timing is started, it has the characteristic that slippage does not start to occur unless the servo pressure is lowered further, and even from this perspective, it is difficult to say that the above technology secures a sufficiently accurate release timing. . Therefore, in the case where the capacity of the hydraulic servo and the return biasing force of its piston are set in accordance with the engagement of the frictional engagement element, and the capacity of the accumulator and the return biasing force of its piston are set in accordance with the engagement of the frictional engagement element, the It is an object of the present invention to provide a hydraulic control device for an automatic transmission for a vehicle, which can obtain release characteristics suitable for smooth release of a frictional engagement element even in the case of a vehicle, and can further reduce shift shock. [Means for Solving the Problems] In order to achieve the above-mentioned object, the first invention selectively connects a hydraulic servo and a hydraulic oil supply/drainage path of the hydraulic servo to a hydraulic power source and a drain oil path. an accumulator connected to a hydraulic oil supply and discharge passage of the hydraulic servo via a branch oil supply and discharge passage;
a first throttle means interposed in the branch oil supply and drainage passage;
a check valve provided in parallel with the first restricting means and allowing only the supply of hydraulic oil to the accumulator; In the automatic transmission for a vehicle that engages and disengages, a second throttle means is interposed on the drain oil path side downstream from the confluence of the oil supply and drain passage and the branch oil supply and discharge passage, and the second throttle means is provided. A relief valve is provided in parallel with the hydraulic servo to encourage discharge of the hydraulic fluid until the hydraulic pressure of the hydraulic servo drops to a set value. A second invention also provides a hydraulic servo, a switching valve that selectively connects a hydraulic oil supply and drainage path of the hydraulic servo to a hydraulic power source and a drain oil path, and a hydraulic oil supply and drainage path of the hydraulic servo. an accumulator connected to via a branch oil supply and drainage passage, a first throttle means interposed in the branch oil supply and discharge passage, and an accumulator provided in parallel with the first throttle means. and a check valve that only allows the supply of hydraulic fluid to the automatic transmission for a vehicle, and the automatic transmission for a vehicle engages and disengages a frictional engagement element of the automatic transmission for a vehicle by actuation of the switching valve, wherein the first throttle The means is a pressure regulating valve that regulates the discharge of hydraulic oil from the accumulator until the hydraulic pressure of the hydraulic servo falls to a set value, and the means is a pressure regulating valve that regulates the discharge of hydraulic oil from the accumulator until the hydraulic pressure of the hydraulic servo falls to a set value, and from the confluence of the oil supply and drainage path and the branch oil supply and drainage path. The second throttle means is provided on the downstream side of the drain oil path. [Operation and Effects of the Invention] In the hydraulic control device for an automatic transmission for a vehicle according to the first aspect of the present invention, the second throttle means is provided on the drain oil path side downstream of the confluence of the oil supply and discharge path and the branch oil supply and drainage path. At the same time, a relief valve is provided in parallel with the second throttle means to help discharge the hydraulic oil until the hydraulic pressure of the hydraulic servo drops to the set value, so that the hydraulic servo and hydraulic pressure are removed in order to release the frictional engagement element. When the eumulator is connected to the drain oil path, the discharge of hydraulic oil from the hydraulic servo is facilitated, and the oil pressure of the hydraulic servo is rapidly reduced while being lower than the oil pressure of the accumulator until it drops to the set value. As a result, a force is generated in a timely manner to overcome the static friction of the friction engagement element when it starts moving from a stopped state, and a smooth start of the release operation is ensured. Therefore, according to the present invention, it is possible to further reduce the shift shock. Further, according to the second invention, there is provided a pressure regulating valve that regulates the discharge of hydraulic oil from the accumulator until the oil pressure of the hydraulic servo falls to a set value, and a confluence point between the oil supply and drainage path and the branch oil supply and drainage path. By providing the second throttling means on the drain oil path side further downstream, when the hydraulic servo and the accumulator are connected to the drain oil path in order to release the frictional engagement element, as in the case described above, the amount of water from the accumulator is The discharge of hydraulic fluid from the hydraulic servo is regulated, and the prompt discharge of hydraulic fluid from the hydraulic servo ensures a smooth and timely start of the hydraulic servo. Therefore, in this invention, as in the case of the first invention, it is possible to obtain the effect that the shift shock can be further reduced. [Embodiment] A hydraulic control device for a vehicle automatic transmission according to the present invention will be described based on an embodiment shown in the drawings. Prior to a detailed explanation of the embodiment, first, the overall structure of the automatic transmission will be explained. FIG. 5 shows a cross section of an automatic transmission for a vehicle. The automatic transmission 100 includes a fluid transmission device (torque converter in this embodiment) 200, a transmission 300, and a hydraulic control device 400. The transmission 300 includes a first planetary gear set p1, 1 operated by a hydraulic servo.
1 multi-disc clutch C0, 1 multi-disc brake B
0, and an overdrive planetary gear transmission 10 with one one-way clutch F0, a second planetary gear set p2, a third planetary gear set p3, two multi-disc clutches C1, C2, 1 operated by hydraulic servos. Two belt brakes B
1. An underdrive planetary gear transmission 40 with three forward stages and one reverse stage, which is equipped with two multi-disc brakes B2, B3 and two one-way clutches F1, F2.
It consists of A case 110 of the automatic transmission 100 includes a torque converter housing 120 that houses a torque converter 200, an overdrive planetary gear transmission 10, and an underdrive planetary gear transmission 40.
and an extension housing 140 that covers the rear side of the automatic transmission 100. These torque converter housing 120, transmission case 130, and extension housing 140 and are each fastened with a large number of bolts so that they have coaxial centers. The torque converter 200 is housed in a torque converter chamber 121 that is open at the front (engine side) of the torque converter housing 120, and includes a front cover 111, which is an input member connected to the output shaft of the engine, and is welded to the front cover 111 at the outer periphery. a circular plate-shaped rear cover 112, a pump impeller 205 disposed around the inner peripheral wall of the rear cover 112, a turbine runner 206 disposed opposite to the pump impeller 205, and holding the turbine runner 206. The turbine shell 207 is connected to the fixed shaft 2 through the one-way clutch 202.
03, and a friction surface 2 provided on the inner surface of the front cover 111.
A lock-up clutch 80 is comprised of an annular plate-shaped clutch disk 50 whose inner periphery is connected to a turbine hub 208 which is an output member, and which directly connects the front cover 111 and the turbine hub 208. We are prepared. A gear type oil pump 1 is disposed inside between the torque converter chamber 121 and a cylindrical transmission chamber 132 of the transmission case 130 which is continuous to the rear thereof.
An annular oil pump body 151 having a cylindrical portion 152 protruding forward from the center thereof is fitted and fastened to the front end surface of the transmission case 130. An oil pump cover 154 having a cylindrical front port 153 that is coaxial with the cylindrical portion 152 and projects rearward is fastened to the rear side. The oil pump body 151 and the oil pump cover 154 form an oil pump housing 155, which serves as a partition wall between the torque converter chamber 121 and the transmission chamber 132, and also serves as a front support wall of the transmission 300. Further, in the middle of the transmission chamber 132 of the transmission case 130, there is an intermediate support wall 159 that separates the overdrive mechanism chamber 133 and the underdrive mechanism chamber 134 and has a cylindrical center support 158 that projects rearward. It is cast separately and fitted. At the rear of the transmission case 130, there is a cylindrical rear support 156 that protrudes forward.
A rear support wall 157 is integrally cast with the transmission case 130. The space between the oil pump housing (front support wall or partition wall) 155 and the rear support wall 157 forms a transmission chamber 132 that houses the transmission 300, and the space between the rear support wall 157 and the extension housing 140 forms a transmission device. In the output shaft chamber 141, an electronically controlled sensor rotor 143 and a speedometer drive gear 144 are fixed to the output shaft, and the front support is provided at the rear end. A sleeve yoke (not shown) is inserted coaxially with 153 and connected to a propeller shaft (not shown). Inside the front support 153, the input shaft 11 of the transmission, which is the output shaft of the torque converter 200, is rotatably supported inside the fixed shaft 203. The input shaft 11 has a flange portion 12 on the outer periphery behind the front support 153.
It has a large-diameter rear end portion 12 provided with a diameter a, and a rearward-facing center hole 13 is formed in the axis of the rear end portion 12. Behind the input shaft 11, an intermediate transmission shaft 14 having a coaxial center with the input shaft 11 and arranged in series is rotatably provided. The intermediate transmission shaft 14
The tip is inserted into the center hole 13 and rotatably slides into contact with the inner circumferential wall of the center hole 13 via a metal bearing, and the large diameter rear end 15 has a center hole facing rearward to the axis. 16 are formed.
An output shaft 36 is rotatably provided behind the intermediate transmission shaft 14 and is coaxial with the intermediate transmission shaft 14 and arranged in series. The tip of the output shaft 36 is inserted into the center hole 16 of the intermediate transmission shaft 14, and is in sliding contact with the inner wall of the center hole 16 via a metal bearing. The output shaft 36 is connected to the ring gear R2 of the third planetary gear set p2 at the intermediate portion 37.
It is spline-fitted to a flange plate 82 having a shaft support part 81 that meshes with the shaft support part 81 and protrudes rearward, and is spline-fitted to the sleeve yoke at the rear part 38. In the overdrive mechanism chamber 133, a first planetary gear set p is installed on the rear side of the input shaft 11.
1, the ring gear R0 is connected to the intermediate transmission shaft 14 via a flange plate 22, and the planetary carrier P0 is connected to the flange portion 12 of the input shaft 11.
a, and the sun gear S0 is connected to the inner race shaft 2.
It is formed in 3. On the front side of the first planetary carrier set p1, a first hydraulic servo drum 24 that opens rearward is fixed to the inner race shaft 23, and an annular piston 25 is fitted between the outer peripheral wall and the inner race shaft 23. , a return spring 26 is provided on the inner race shaft 23 side to form a hydraulic servo C-0 of the clutch C0, and the clutch C0 is further mounted inside the outer peripheral wall, and the first hydraulic servo drum 24 forms a hydraulic servo C-0 of the clutch C0. It is connected to planetary carrier P0 via. A one-way clutch F0 having the inner race shaft 23 as an inner race is provided on the inner periphery of the first hydraulic servo drum 24, and a clutch C0 and a brake B0 are provided on the outer periphery between the outer race 27 and the transmission case 130. A piston 2 is attached to the front side of the outer cylindrical portion 31 of the intermediate support wall 159 on the rear side.
9 is fitted, and a return spring 32 is fitted to the tip of the outer cylinder portion 31 to form a hydraulic servo B-0 of the brake B0. Inside the underdrive mechanism chamber 134, at the front, a second hydraulic servo drum 41 that opens rearward is rotatably fitted onto the center support 158, and an annular piston 42 is fitted between its inner and outer circumferential walls to drive the clutch C2. A hydraulic servo C-2 is formed, and a return spring 44 is attached to the inner circumferential wall thereof, and a clutch C2 is attached to the inner circumferential wall thereof. On the rear side of the second hydraulic servo drum 41, there is a third hydraulic servo drum 46 which is open to the rear and has a cylindrical clutch hub 35 welded to the front.
is fixed to the rear end 15 of the intermediate transmission shaft 14, and the annular piston 4 is provided between the rear end 15 and the outer peripheral wall.
7 is fitted and the hydraulic servo C- of the clutch C1
1 is formed, a return spring 49 is attached to the inner circumferential side thereof, and a clutch C2 is attached to the outer circumference of the clutch hub 35, and a second hydraulic servo drum 41 and a third hydraulic servo drum 46 are connected via the clutch C2. There is. A second planetary gear set p2 is provided on the rear side of the third hydraulic servo drum 46, and its ring gear R1 is connected to the third hydraulic servo drum 46 via a clutch hub 48 and a clutch C1. The sun gear S1 is spline-fitted to the tip of the output shaft 36, and is integrally formed with the sun gear shaft 45. In addition, a connecting drum 60, which is formed to cover the second and third hydraulic servo drums 41 and 46 and the second planetary gear set p2 in a minimum space, is attached to the outer periphery of the second hydraulic servo drum 41 at its tip. The rear end is connected to the sun gear shaft 45 on the rear side of the second planetary gear set p2, and a belt brake B1 is provided on the outside thereof. The spline 75 formed inside the transmission case 130 on the rear side of the brake B2 has a spline 75 formed on the inside of the transmission case 130 on the rear side of the brake B2.
2. The outer spline 76 of the fourth hydraulic servo drum 72 and the brake disc b3 of the brake B3 are spline-fitted, and the rear support wall 157 on the rear side
A piston 77 is fitted into an annular hole between the outer peripheral side of the rear port 156 and the transmission case 130 to form a hydraulic servo B-3 of the brake B3, and a return spring 79 of the hydraulic servo B-3 is It is supported by a retainer attached to the tip of the support 156. A one-way clutch F1 whose inner race is the sun gear shaft 45 is provided inside the brake B2, and its outer race 39 is connected to the brake B2.
Inner race 83 on the rear side of the one-way clutch F1
A one-way clutch F2 spline-fitted to the fourth hydraulic servo drum 72 is installed. In the third planetary gear set p3, the sun gear S2 is formed integrally with the sun gear shaft 45, the planetary carrier P2 is connected to the outer race 86 of the one-way clutch F2 on the front side, and is also connected to the brake B3, and the parking gear 85 is attached to the outer periphery. A circumferential ring gear R2 is connected to an intermediate portion 37 of the output shaft 36. The parking gear 85 operates when the shift lever of the automatic transmission is selected to the parking P position.
The parking claw 84 meshes with the parking gear 85 to fix the output shaft 36. An annular fourth hydraulic servo drum 72 that is open to the front is provided in the surplus space 61 on the rear side of the connecting drum 60 outside the second planetary gear set p2. A press-molded intermediate cylinder 71 is provided that protrudes from a predetermined position within the fourth hydraulic servo drum 72, is connected to the fourth hydraulic servo drum 72 by a welded portion 71A, and prevents oil pressure leakage from the hydraulic servo. There is. Fourth hydraulic servo drum 72 and intermediate cylinder 71
An annular piston 73 is fitted between the brake B2 and the hydraulic servo B-2 of the brake B2.
The inner peripheral wall of the fourth hydraulic servo drum 72 and the intermediate cylinder 71
A return spring 74 is installed between the two, and a brake B2 is installed inside the outer peripheral wall. The intermediate cylinder 7
1 makes the area of the piston 73 the optimum diameter. The transmission 300 operates according to vehicle running conditions such as vehicle speed and throttle opening from a hydraulic control device 400 in a valve body 403 built in an oil pan 401 fastened to the lower part of the transmission case 130 with bolts 402. The hydraulic pressure selectively output to the hydraulic servo of the frictional engagement device engages or releases each clutch and brake, thereby changing gears to four forward speeds or one reverse speed. Table 1 shows an example of the operation of each clutch, brake, and one-way clutch and the achieved gear position (RANGE).

[Table] In Table 1, E indicates that the corresponding clutch or brake is engaged. L indicates that the corresponding one-way clutch is engaged only in engine drive conditions and not in engine brake conditions. Furthermore, the corresponding one-way clutch of L is engaged in the engine drive state, but this engagement is not necessarily necessary because power transmission is guaranteed by a clutch or brake built in parallel. Indicates that it is not locked. Furthermore, f indicates that the corresponding one-way clutch is free. Additionally, an x indicates that the corresponding clutch and brake are released. ○ in S1 and S2 indicates that the solenoid is ON. × in S1, S2, and S3 indicates that the solenoid is OFF. ◎ in S3 indicates that the direct coupling clutch is ON when the solenoid is ON, and indicates that the direct coupling clutch is OFF when the solenoid is OFF. FIG. 6 shows a hydraulic circuit of the hydraulic control device 400 for the automatic transmission shown in FIG. The hydraulic circuit is an oil pan 401 shown in FIG.
An oil strainer 410, an oil pump 411, a cooler bypass valve 415, a pressure relief valve 416, a release clutch control valve 417, and a release brake control valve 41 are fastened to the lower surface of a hydraulic valve body 403 built into the
8. Lock-up relay valve 420, pressure regulating valve (regulator valve) 430, second pressure regulating valve 45
0, cutback valve 460, said direct coupling clutch 5
0 when the lock-up relay valve 4 is released.
Lock-up control valve 470 for controlling the speed of exhaust pressure from drain oil passage 6D from 20;
accumulator control valve 480, second accumulator control valve 490, throttle valve 500,
A manual valve 510 that is a hydraulic switching valve manually operated by the driver, each shift valve that is an automatic hydraulic switching valve (1-2 shift valve 520, 2-3 shift valve 530, 3-4 shift valve 540), brake B1
An intermediate coast modulator valve 545 that adjusts the hydraulic pressure supplied to servo B-1 of brake B3, a low coast modulator valve 550 that adjusts the hydraulic pressure supplied to servo B-3 of brake B3, engagement of clutch C0, An accumulator 560 that smoothly releases the brake, an accumulator 570 that smoothly engages the brake B0, and an accumulator 58 that smoothly engages the clutch C2.
0. Accumulator 590 for smooth engagement of brake B2, clutches C0, C1, C2
and flow control valves (throttles) 601, 603, 60 with check valves that control the flow rate of pressure oil supplied to each hydraulic servo of brakes B0, B1, B2, and B3.
4,605,606,607,608,609,
Shuttle valve 602, electronic circuit (computer)
the first solenoid valve S1, which is opened and closed by the output of
A second control valve controls both the 0 and 3-4 shift valves 540.
the solenoid valve S2, the lock-up relay valve 420, and the lock-up control valve 47.
0, a third solenoid valve S3, oil passages communicating between the valves and the hydraulic cylinders of the clutch and brake, and a throttle appropriately inserted into each oil passage, and S is provided between each oil passage. The oil strainer is shown below. From oil pan 401 to oil strainer 410
The hydraulic oil pumped up by the hydraulic pump 411 is adjusted to a predetermined oil pressure (line pressure) by a pressure regulating valve 430 and then supplied to the oil path 1 . The surplus pressure oil that has flowed into the oil line 6 connected to the oil line 1 via the pressure regulating valve 430 is controlled by the second pressure regulating valve 450 to a predetermined secondary line pressure (torque converter pressure),
Lubricating oil path L1 of transmission 300 and lubricating oil path L of extension housing 140
The lubrication oil pressure is adjusted to 2. Also, a part of the oil discharged from the oil pump is transferred from oil path 1 or oil path 6 to the oil cooler O/C via the lock-up relay valve 420.
is supplied to and cooled. The pressure regulating valve 430 has a spring 4 at the top in the figure.
The spool 432 is connected to the upper end land 436 of the plunger 438 through an oil passage 9 from above in the drawing.
When moving backward, the oil passage 5 is further
It receives line pressure applied to the lower end land 437 of the plunger 438 from below, and receives feedback pressure of the line pressure applied from the lower end of the spool 432 to the lower end land 433 of the spool 432 from the lower side in the drawing, and is displaced. The communication area with the port 435 is adjusted to output line pressure to the oil passage 1 according to vehicle running conditions. The manual valve 510 is provided in the driver's seat and is connected to a shift lever (select lever) for selecting a gear shift range, and is manually operated to select P (park), R (reverse), or R (reverse) depending on the shift lever range. Move to the N (neutral), D (drive), S (second) or L (low) positions. Table 2 shows the communication state between oil passage 1 and oil passages 2 to 5 in the shift range of each shift lever. 〇 indicates that each oil passage 2 to 5 communicates with oil passage 1 and line pressure is supplied, and × indicates that each oil passage 2 to 5 is discharged to the drain port of the manual valve. .

[Table] In the throttle valve 500, a cam 505 rotates in accordance with the amount of depression of the accelerator pedal, and a throttle plunger 501 strokes, and a spool 502 on which the plunger 501 and a spring 504 are disposed behind.
The spool 502 is moved via the spring 503 between the spool 502 and the line pressure supplied from the oil passage 1 is regulated to a throttle pressure according to the throttle opening degree and output to the oil passage 9. The lock-up relay valve 420 is connected to the spool 42
2 (upper part shown) and plunger 424 (lower part shown)
and are arranged in series via a spring 426. The spool 422 has an illustrated upper end land 422A, an intermediate land 422B, and an illustrated lower end land 422C, and is connected from above to the oil passage 2A via a throttle r10, and is connected to the solenoid of the oil passage 2D in which the solenoid valve S3 is provided. pressure
Ps and is displaced from below by the spring load of the spring 426. The solenoid pressure
When Ps is less than the set value Ps1 shown in FIG. 2, the spool 422 is set upward in the figure because the spring load of the spring 426 is greater, and the oil is connected directly to the oil passage 6, which is the hydraulic pressure source of the torque converter 200, to release the clutch. A drain oil passage 6C, which is a circulation oil passage of the oil cooler in this embodiment, communicates with the oil passage 6A.
The engagement side of the direct coupling clutch communicates with the oil passage 6B. As a result, the clutch release side 50A of the clutch disk 50 has a higher oil pressure than the clutch engagement side 50B, the clutch disk 50 separates from the friction surface 20 of the front cover, and the direct coupling clutch 80 is released. Also, the solenoid pressure of oil path 2D
When Ps is greater than or equal to the setting range Ps2, the spool 422 is set downward in the figure, and the oil passage 6 communicates with the oil passage 6B, and in this embodiment, the oil passage 6A communicates with the drain port via the throttle r1 and serves as a relief valve. Lock-up control valve 47 also has the function of
It communicates with the drain oil passage 6D that communicated with the drain port 47b of No. 0. As a result, the oil pressure at the clutch engagement surface 50B of the clutch disk 50 becomes higher than the oil pressure at the clutch release surface 50A, the clutch disk 50 is pressed against the friction surface 20, and the direct coupling clutch 80 is engaged. In this case, the solenoid pressure in the oil passage 2D is duty-controlled by the solenoid valve S3, so precise hydraulic control is possible according to vehicle running conditions such as vehicle speed and throttle opening, and the pressure can be raised and lowered smoothly. The direct coupling clutch can be smoothly engaged and released through the clutch state. The lock-up control valve 470 includes a spool 472 (lower part in the figure) and a large diameter plunger 474.
(upper part in the figure) are arranged in series, and a spring 476 is placed behind the lower end of the spool 472.
The large-diameter land 474A of the spool 472 and the plunger 474 receives the solenoid pressure Ps of the oil passage 2D applied to the upper end oil chamber 471 in the figure, and the spring load of the spring 476 applied from below to the spool 472 and the oil passage 1 The line pressure (related to the throttle pressure) is inputted to the illustrated lower end oil chamber 477 from the spool 472 and applied to the illustrated lower end land 478 of the spool 472, and the oil chamber 475 intermediate between the spool 472 and the plunger 474 receives line pressure (related to the throttle pressure).
It is displaced in response to the hydraulic pressure of the drain oil passage 6D supplied through the throttle r2. When the drain oil passage 6D is connected to the oil passage 6A, the spool 472 is connected to the oil passage 6 which is applied to the upper end land 479 if the solenoid pressure Ps is below the set value.
The normally open import 47a is displaced by the hydraulic pressure from D and the spring load of the spring 476, and when the solenoid pressure Ps is higher than the set value, it is displaced by the solenoid pressure Ps and the spring load of the spring 476, and is connected to the oil path 6D. The degree of communication between the drain port 47b and the drain port 47b is adjusted, and the speed of oil drainage from the drain port 47b is adjusted (relief control).
This exhaust pressure is maintained until the clutch disc 50 of the direct coupling clutch contacts the friction surface 20. This allows the direct coupling clutch 80 to quickly start engaging. After the contact, the pressure in the oil passage 6D is gradually released through the throttle r1 arranged in parallel with the lock-up control valve 470, which is a relief control valve, and the direct coupling clutch capacity increases smoothly.
The exhaust pressure from the drain port 47b is set to be released when the duty ratio of the solenoid valve S3 is in a first region Z2, and thereby the clutch disc is adjusted according to vehicle running conditions such as vehicle speed and throttle opening. The hydraulic pressure applied to the clutch release surface 50A of the clutch 50 is gradually lowered to smoothly engage the direct coupling clutch 80 under a wide range of vehicle running conditions, thereby reducing the engagement shock of the direct coupled clutch 80. Further, a port 47c that communicates with the oil passage 6 is provided above the import 47a in the drawing, and when the spool 472 is set in the upper part of the drawing, the drain port 47b connects the oil passage 6D with the oil passage 6. closed, spool 472
When is set to the lower part of the figure, port 47c
is closed, and the oil passage 47a is connected to the drain port 47b.
contact. Further, when the spool 472 is in the middle, the opening degree of the port 47c and the drain port 47b is adjusted by the position of the spool 472. As a result, the pressure discharge speed from the oil passage 6D can be smoothly controlled without reducing the pressure inside the torque converter, and the effect of preventing cavitation inside the torque converter can be improved. In this case, the solenoid pressure in the oil passage 2D is the solenoid valve S
Since pulsation occurs due to the duty control of No. 3, it is desirable to install a relatively strong hydraulic vibration damping device such as a throttle or capacitor in a portion of the upper end oil chamber 471 near the import. Also spool 47
In order to prevent rocking of the lock-up control valve 470, a damping device such as a throttle may be installed at each in-out port of the lock-up control valve 470. Furthermore, in this embodiment, the line pressure Pl of the oil passage 1, which is an example of the oil pressure Pi that changes mainly in relation to the vehicle speed, is introduced into the illustrated lower end oil chamber 477 in which the spring 476 is installed on its back, and the line pressure Pl of the oil passage 1 is introduced into the lower end oil chamber 477 shown in the drawing, which has a spring 476 installed behind it. The start timing of the transmission torque and the rise of the transmission torque capacity are related to vehicle running conditions. This allows the engagement of the direct coupling clutch to be optimally controlled over a wide range of vehicle driving conditions. The first solenoid valve S1 generates high-level solenoid pressure (equal to line pressure) in the oil passage 2G communicating with the oil passage 2 via the throttle r11, and when energized, discharges the pressure oil in the oil passage 2G to maintain a low level. Generates solenoid pressure. The second solenoid valve S2 generates high-level solenoid pressure in the oil passage 1H that communicates with the oil passage 1 via the throttle r12 when it is not energized, and discharges the pressure oil in the oil passage 1H when it is energized to generate a low-level solenoid pressure. arise. The third solenoid valve S3 is a lock-up relay valve 4 that is duty-controlled as described above and communicates with the oil passage 2D that communicates with the oil passage 2 via the throttle r10.
The oil pressure in the illustrated upper end oil chamber 421 of No. 20 and the illustrated upper end oil chamber 471 of the lockup control valve 470 is controlled. Table 1 shows energization (〇) and non-energization (×) of solenoid valves S1 and S2 controlled by electronic circuits.
This shows the relationship between the shift position of the shift lever and the shifting state of the automatic transmission. The 1-2 shift valve 520 has a spring 52 located downward in the figure.
When the solenoid valve S2 is de-energized (OFF) and high-level solenoid oil pressure is generated in the oil passage 1H, the high-level solenoid pressure enters the oil chamber 524 at the upper end in the figure. By applying the oil pressure, the spool 522 is set to the lower position in the drawing and becomes the first speed position, and when the solenoid valve S2 is energized (ON) and the pressure oil in the oil path 1H is discharged and the solenoid pressure is at the low level. The spool 522 is set upward in the drawing to obtain the second speed position. In the 3rd and 4th speeds, line pressure enters the lower end oil chamber 523 from the oil passage 1C that communicates with the oil passage 1B via the oil passages 1 and 2-3 shift valve 530, and the spool 522 is activated regardless of the solenoid pressure. It is fixed at the top shown in the figure. The 2-3 shift valve 530 has a spring 53 located downward in the figure.
When the solenoid valve S1 is energized and the oil passage 2G is at a low level solenoid pressure, the spool 532 is set upward in the figure by the action of the spring 531.
When it is in the second speed position and the solenoid valve S1 is de-energized, high-level solenoid pressure is generated in the oil passage 2G and applied to the oil chamber 534, and the spool 532 is set to the lower position in the figure due to the action of this solenoid pressure. This is the 3rd and 4th gear position. When line pressure is supplied to the oil passage 4, the line pressure is supplied to the lower end oil chamber 533, and the spool 532 is locked at the upper position in the drawing, which is between the first and second speeds. The 3-4 shift valve 540 has a spring 54 located downward in the figure.
The oil passages 1 and 2 are equipped with a spool 542 with a
-3 shift valve 530, 1st speed, 2nd speed where line pressure is supplied to the lower end oil chamber 544 via the oil path 1B
At high speed, the spool 542 is locked upward in the figure (toward the third speed) by the action of the line pressure and the spring 541 regardless of the solenoid pressure, the solenoid valve S2 is energized, the oil passage 1H is evacuated, and the low level is reached. In the second and third speeds where the hydraulic pressure is
1, the spool 542 is set upward in the figure, and in the fourth speed, the solenoid valve S2 is de-energized, high-level solenoid pressure is generated in the oil passage 1H, and is applied to the upper end oil chamber 543. The spool 542 is set at the bottom in the figure. The cutback valve 460 receives the spring load of a spring 461 placed behind it from above in the figure, and has a spool 462 that is displaced by receiving the line pressure of the oil passage 2A from the other side, and the line pressure is supplied to the oil passage 2A. The spool 462 is set upward in the figure to communicate the oil passage 9 in which throttle pressure is generated with the cutback pressure output oil passage 9A, outputting the throttle pressure as cutback pressure, and controlling the throttle valve 50.
A cutback pressure is applied to the lower end land 507 of the spool 502 shown in FIG. Due to this level reduction of the throttle pressure, the spool 432 of the regulator valve 430 which uses the throttle pressure as the input oil pressure is displaced upward in the drawing, and the line pressure of the oil passage 1 is leveled down, so-called line pressure cutback is performed. First accumulator control (control)
The valve 480 has a spool 481 at the bottom in the figure,
The spring 48 is connected in series with the spool 481 in the upper part of the figure.
2, and has a large-diameter plunger 483 in which a cylindrical part is formed that protrudes (downward in the figure) so that the upper end of the spool-side outer circumference in the figure encompasses the lower end of the plunger-side outer circumference of the spool 481 in the figure. , the spool 481 is connected to the lower end oil chamber 484 via the oil passage 1 from below.
The line supplied from the oil passage 1 is displaced by the spring load from the spring 482 from above and the feedback of the output oil pressure applied from the oil passage 1M to the upper end oil chamber 485 via the throttle r13. The pressure is regulated and output to the oil path 1M as the output oil pressure P1. The second accumulator control valve 490 has a spool 492 with a spring 491 mounted on its back in the lower part of the figure, and an oil hole 494 with a restrictor R14 is formed in the upper end land 493 of the spool 492, and the upper end oil chamber 49
5 and the intermediate oil chamber 496 are connected. Spool 4
92 is a spring load by a spring 491 from below,
From the oil passage 9 to the large diameter lower end land 4 of the spool 492
It receives the throttle pressure Pth applied to the oil passage 1M and the feedback of the output oil pressure (accumulator control pressure Pa) applied to the upper end land 493 from above through the oil passage 1M and the throttle r14, and is displaced from the oil passage 1M. The supplied output oil pressure P1 of the first accumulator control valve is regulated, and the oil passage 1Q is set as the accumulator control pressure Pa.
Output to. Next, the operation of the hydraulic control device by manual shifting of the manual valve 510 will be explained. When the manual valve 510 is shifted to the N range, oil passage 1 does not communicate with any of oil passages 2 to 5 as shown in Table 2, and the first and second solenoid valves S1 are energized as shown in Table 1. , S2 are de-energized. Therefore, the spools of the 1-2 shift valve 520, the 2-3 shift valve 530, and the 3-4 shift valve 540 are all positioned upward in the figure by the action of the spring. 3-4 to oil path 1 without going through manual valve 510
Only the clutch C0, which is in direct communication with the shift valve 540, the oil passage 1F, and the flow control valve with check valve 601, is engaged. When manual valve 510 is shifted to D range. As shown in Table 2, line pressure is supplied to the oil passage 2 and the clutch C1 is engaged. When starting the vehicle, solenoid valve S is activated as shown in Table 1.
1 is energized, solenoid valve S2 is de-energized and 1-2
The spool 522 of the shift valve 520 is located at the bottom in the figure, and is connected to the oil passages 3B and 2 that communicate with the brakes B1 and B2.
A is an oil path 5C which is depressurized and connects to brake B3.
Since hydraulic pressure is not supplied to brakes B1 and B
2 and B3 are released and the vehicle runs in first gear. During automatic gear shifting, when the vehicle speed reaches a preset value as shown in Table 1, the solenoid valve S2 is energized by the output of the computer, and the solenoid pressure applied to the oil chamber 524 of the 1-2 shift valve 520 is reversed to a low level. Therefore, the spool 522 of the 1-2 shift valve 520 moves upward in the figure, and hydraulic pressure is supplied through the oil passage 2, the 1-2 shift valve 520, the oil passage 2A, and the flow control valve with check valve 608, and the brake B2 is engaged, resulting in an upshift to second gear. To upshift to third gear, when the vehicle speed, throttle opening, etc. reach predetermined values, the solenoid valve S1 is de-energized by the output of the computer, and the spool 532 of the 2-3 shift valve 530 moves downward in the figure.
Oil passage 1, 2-3 shift valve 530, oil passage 1B, shuttle valve 602, flow control valve with check valve 60
3. Hydraulic pressure is supplied to clutch C via oil path 1P.
2 is engaged, and at the same time, the spool 522 of the 1-2 shift valve 520 is fixed upward in the drawing (toward the 2nd speed) by line pressure supplied from the oil passage 1C to the lower end oil chamber 523. In order to upshift to 4th gear, as described above, the solenoid valve S2 is de-energized by the output of the computer, the solenoid pressure that was being supplied from the oil passage 1H to the upper end oil chamber 543 is reversed to a high level, and the 3-4 shift valve 5
The spool 542 of No. 40 moves downward in the figure, and the pressure in the oil passage 1F is exhausted, and the oil pressure is supplied to the oil passage 1P.The oil pressure is supplied to the oil passage 1L through the flow control valve with check valve 605, and the clutch C0 is activated. At the same time as the brake is released, the brake B0 is engaged. When manual valve 510 is in S range. In addition to the oil passage 2, line pressure is supplied to the oil passage 3. 1st, 2nd, and 3rd gears are shifted in the same manner as in the D range, but line pressure enters the lower end oil chamber 544 of the 3-4 shift valve 540 via oil path 3 and oil path 1E, and the spool 542 Since it is fixed at the upper position in the figure, no shift to fourth gear occurs. In the second gear, line pressure is supplied from the oil passage 2 to the oil passages 2A and 2D via the 1-2 shift valve 50, as in the second gear of the D range, and at the same time, line pressure is supplied from the oil passage 3 to the 2-3 shift valve 50. Valve 530, oil path 3A, 1-2
Since line pressure is also supplied to the oil passage 3B via the shift valve 520, the line pressure is supplied to the oil passage 3C, and the second speed in which both the brake B2 and the brake B1 are constantly engaged is achieved, and the S range is reached. In the second gear, engine braking is applied during coasting and the transmission torque capacity is increased. Furthermore, if the manual valve 510 is in the D position and a D-S shift is performed manually while running in fourth gear, the line pressure is introduced into the lower end oil chamber 544 of the 3-4 shift valve 540 as described above, so that the third When the speed has been reduced to the scheduled speed, the computer output energizes the solenoid valve S1, causing a 3-2 downshift and obtaining the second speed where engine braking is effective. When manual valve 510 is in L range. In addition to the oil passages 2 and 3, line pressure is also supplied to the oil passage 4. In the 1st and 2nd speeds, the same shift as in the D range is performed, but line pressure enters the lower end oil chamber 533 of the 2-3 shift valve 530 from the oil passage 4, and the spool 532 is fixed upward in the figure. No shift to third gear occurs. In addition, the first speed is braked by the oil pressure supplied through the oil passage 4, the 2-3 shift valve 530, the oil passage 4A, the low coast modulator valve 550, the oil passage 4B, the 1-2 shift valve 520, and the oil passage 5C. Engine braking is activated by engaging B3. The second speed is the same as when the manual valve 510 is shifted to the S range. Also, when manually shifting to L range while driving in 3rd gear, the 2-3 shift valve 5
By introducing line pressure to the lower end oil chamber 533 of 30, a downshift is immediately performed to the second speed, and when the speed has been decelerated to the scheduled speed, the computer output energizes the solenoid valve S2, causing a 2-1 downshift. . When manual valve 510 is in R range. As shown in Table 2, hydraulic pressure is supplied to the oil passage 5, and the shuttle valve 602 and flow control valve with check valve 603
Then, line pressure is supplied through the oil passage 1P, and the clutch C2 is engaged. Also, solenoid valve S1
is ON, the solenoid pressure in the upper end oil chamber 534 of the 2-3 shift valve 530 is at a low level, the spool 532 is set upward in the figure, line pressure is supplied from the oil path 1 to the oil path 1E, and the 3-3 shift valve 530 is turned on. Line pressure is supplied to the lower end oil chamber 544 of the 4-shift valve 540, and regardless of whether the solenoid valve is ON or OFF, the spool 542 is set upward, and line pressure is supplied from oil passage 1 to oil passage 1F, and the clutch is C0
is engaged. In addition, the 1-2 shift valve 520 is supplied with line pressure to the lower end oil chamber 523 via the oil passage 1C, so the solenoid valve S2 is turned ON and OFF.
Regardless, the spool 522 is set upward in the drawing, line pressure is supplied to the oil passage 5C, and the brake B3 is engaged. Manual valve 510 is D or S, S or L
If the engine is shifted to each range, line pressure is generated in the oil passage 2, and the 1-2 shift valve 520 is set to the second gear side (upper side in the figure), line pressure is generated in the oil passage 2D, The aforementioned direct clutch control is performed. Here, the hydraulic control device according to the present invention will be described in detail below. Within the hydraulic control device 400, the configuration according to the first invention is applied to the following parts. (a) Hydraulic servo B-0, accumulator 57
Brake B consisting of 0, 3-4 shift valve 540, release brake control (relief) valve 418, and throttle with check valve 605, 606
0 hydraulic control circuit (b) Hydraulic servo C-2, accumulator 58
0, throttle with check valve 603, 604, shuttle valve 602, 2-3 shift valve 530, release brake control (relief) valve 417
1. Hydraulic control circuit for clutch C2 consisting of a clutch C2 and a diaphragm FIG. 1 is a circuit configuration diagram of an embodiment showing only a portion of a control circuit to which the configuration of the first invention is applied. As shown in this figure, the hydraulic control circuit is
Return spring 920 inside cylinder 920A
A hydraulic servo 920 into which a piston 920C equipped with B is fitted, a switching valve 950 for switching communication between the hydraulic servo 920 and the hydraulic source 950A or the drain oil path 950B, and between the hydraulic servo 920 and the switching valve 950. interposed in the cylinder 980
The accumulator 980 is equipped with a piston 980C fitted with a return biasing means 980B such as a spring or back pressure inside the accumulator 980. M is said to be engaged and released. In this example, the throttle with check valve 95
0C is interposed between the confluence of the oil supply and drainage passage and the branch oil supply and drainage passage and the switching valve 950, and the drain oil passage 95
A second throttle means _R20 is interposed in 0B, and a relief valve Vr is provided in parallel with the second throttle means _R20 . In this figure, the symbol R ₁₀ indicates the first throttle means, and q1 indicates a check valve that only allows the supply of hydraulic oil to the accumulator _. This prevents the accumulator 980 from having excessive resistance when boosting the voltage. Furthermore, the reference numerals given in the above-mentioned general description are shown in parentheses to correspond to the elements. This hydraulic control circuit includes an accumulator 980
In order to release the friction engagement element M, the hydraulic servo 920 and the accumulator 980 are connected to the drain oil path via the switching valve 950. 95
When contacting 0B, the first throttle means R ₁₀ and the second throttle means regulate the discharge of hydraulic fluid from the accumulator 980 and promote discharge from the hydraulic servo 920.
Performed by R ₂₀ . In this case, for example, if the return biasing forces of the hydraulic servo 920 and the accumulator 980 are equal, the first restricting means _R10 is set to have a discharge resistance greater than the second restricting means _R20 by a predetermined value. In _this way, as shown in FIG.
An action is taken to keep it lower, and the hydraulic servo C-
2 servo pressure Ps is lowered to a sufficiently low value Ps, and the corresponding transmitted torque T is the characteristic shown by the solid line in the figure.
From _T1 , it becomes possible to have a characteristic _T2 without a peak Tp as shown by the dotted line. and,
The relief valve Vr provided in parallel with the second throttle means _R20 acts to reduce the oil pressure at point A to a set value of the relief pressure Pr, as shown by the dashed line in FIG. In this way, the relief valve Vr rapidly lowers the servo pressure applied to the piston 920c of the hydraulic servo 920 so that the friction engagement elements M are quickly released from the static friction state in which they are mutually engaged and begin to slide, and is released by the low relief pressure Pr. This ensures the start of the operation. And relief valve Vr
As shown by the dashed line in the figure, it is also possible to input the oil pressure Pi, which changes depending on the vehicle running conditions such as vehicle speed, throttle opening, output shaft torque, and selected position of the select lever. Adjust the relief pressure Pr setting value according to the input oil pressure Pi,
The servo pressure Ps can now be adjusted to suit many running conditions, and the release timing of the frictional engagement element M can be further optimized. Also, instead of the oil pressure Pi, input the oil pressure Pj of the oil passage where oil pressure is generated when the select lever is manually shifted from the drive range to the second range or low range, so that when the manual shift occurs, It is also possible to increase the discharge speed by stopping pressure regulation with the relief valve Vr and fully opening the drain oil passage. In this way,
This provides the effect of speeding up downshifts when engine braking is required. In addition, the throttle with check valve is 950C.
is mainly the servo pressure Ps when the frictional engagement element M engages.
It is inserted to adjust the boost characteristics of. FIG. 2 shows an embodiment of the configuration of the second invention. In this example, the first throttle means described above is connected from a fixed throttle to a pressure regulating valve Vr ₂ that adjusts the discharge of hydraulic oil from the accumulator 980. has been changed. A second throttle means R ₂₀ is provided in the drain oil passage 950B.
is provided. In this example, in order to regulate the discharge of hydraulic oil from the accumulator 980 and encourage the discharge of hydraulic oil from the hydraulic servo 920, the pressure regulating valve Vr ₂ and the check valve q1
and the second restricting means _R20 . and,
As shown by the two-dot chain line in FIG. 3, the servo pressure is maintained during a predetermined time t2 that approximately corresponds to the predetermined time t1.
It is kept at a constant pressure Pr ₂ lower than the accumulator pressure Pa. In this example, as in the previous example, the pressure regulating valve Vr ₂ has a hydraulic pressure that changes depending on vehicle running conditions such as vehicle speed, throttle opening, and output shaft torque.
Pi may be input, and the discharge from the accumulator 980 may be adjusted in accordance with the input oil pressure Pi. In this way, it becomes possible to obtain an appropriate release timing of the frictional engagement element M under a wider range of vehicle running conditions. Although the present invention has been described above in detail based on several embodiments, the present invention is not limited to the above-mentioned embodiments, and various specific configurations may be made within the scope of the claims. Needless to say, it can be implemented with modifications.

[Brief explanation of drawings]

FIG. 1 is a circuit configuration diagram of a hydraulic control device for an automatic transmission for a vehicle showing an embodiment of the first invention, FIG. 2 is a circuit diagram showing an embodiment of the second invention, and FIG. A graph showing the characteristics of servo pressure, accumulator pressure, and transmission torque when the frictional engagement element is released, FIG. 4 is a cross-sectional view of a vehicle automatic transmission, and FIG. 5 is a hydraulic circuit of the hydraulic control device. It is a diagram. M...Frictional engagement element, 920...Hydraulic servo,
950...Switching valve, 950A...Hydraulic power source, 980
...Accumulator, R ₁₀ ...First throttle means,
R ₂₀ ...Second throttle means, q1...Check valve, Vr...
Relief valve, Vr ₂ ...pressure regulating valve, 100...automatic transmission, 400...hydraulic control device.

Claims (1)

[Scope of Claims] 1. A hydraulic servo, a switching valve that selectively connects a hydraulic oil supply/drainage path of the hydraulic servo to a hydraulic power source and a drain oil path, and a hydraulic oil supply/drainage path of the hydraulic servo. an accumulator connected to via a branch oil supply and drainage passage, a first throttle means interposed in the branch oil supply and discharge passage, and an accumulator provided in parallel with the first throttle means. and a check valve that only allows the supply of hydraulic oil to the automatic transmission for a vehicle, and the automatic transmission for a vehicle engages and disengages a frictional engagement element of the automatic transmission for a vehicle by the operation of the switching valve, the automatic transmission for a vehicle comprising: A second throttling means is interposed on the drain oil path side downstream from the confluence of the branch oil supply and drain path, and is arranged in parallel with the second throttling means until the oil pressure of the hydraulic servo falls to a set value. A hydraulic control device for an automatic transmission for a vehicle, characterized by being provided with a relief valve that facilitates discharge of hydraulic fluid. 2 The relief valve is configured to control vehicle speed, throttle opening,
Claim 1, characterized in that a hydraulic pressure that changes according to vehicle running conditions such as output shaft torque and a selected position of a select lever is input, and the set value is adjusted according to the input hydraulic pressure. Hydraulic control system for automatic transmissions for vehicles. 3. The relief valve is provided with an input of oil pressure from an oil passage to which oil pressure is supplied when the selected position of the select lever is shifted to a low speed range, and the set value is adjusted by the input of the oil pressure. A hydraulic control device for a vehicle automatic transmission according to item 1 or 2. 4 A hydraulic servo, a switching valve that selectively connects a hydraulic oil supply and drainage path of the hydraulic servo to a hydraulic power source and a drain oil path, and a branch oil supply and drainage path to the hydraulic oil supply and drainage path of the hydraulic servo. an accumulator connected to the accumulator, a first throttle means interposed in the branch oil supply/discharge path, and a first throttle means provided in parallel with the first throttle means for supplying hydraulic oil to the accumulator. In the automatic transmission for a vehicle, the automatic transmission for a vehicle is equipped with a check valve that allows only the hydraulic servo to engage and release a frictional engagement element of the automatic transmission for a vehicle by the operation of the switching valve. A pressure regulating valve that regulates the discharge of hydraulic oil from the accumulator until the oil pressure falls to a set value,
A hydraulic control device for an automatic transmission for a vehicle, characterized in that a second throttle means is provided on the drain oil path side downstream from the confluence of the oil supply and drain path and the branch oil supply and drain path. 5. The pressure regulating valve receives an input oil pressure that changes depending on vehicle running conditions such as vehicle speed, throttle opening, and output shaft torque, and adjusts the set value according to the input oil pressure. A hydraulic control device for a vehicle automatic transmission according to scope 4.