JPS59166749A - Multistep automatic transmission for vehicle and hydraulic control unit thereof - Google Patents

Abstract

PURPOSE:To prevent a brake band from resiling upward, by securing a sun gear tight enough with a brake engagement and a one-way clutch lock in case of its one rotating direction while in case of the reverse direction, with the engagement of a band brake acting on the same direction. CONSTITUTION:In a specific change gear step, a sun gear 312 is locked and at a change gear step at the low speed side, the sun gear 312 rotates in one direction alone but at a change gear step at the high speed side, it rotates in the reverse direction. The sun gear 312 is secured tight with the engagement of a brake B2 and the lock of a one-way clutch F1 for the one rotating direction side, but for the reverse rotating direction side, with the engagement of a brake band 340 acting on the same direction as the reversed. Therefore, resiling motion in a band of the band brake can be prevented so that a torque variation in an output shaft goes smoothly.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic transmission for a vehicle using a band brake. .

In a vehicle automatic transmission using a planetary gear transmission that connects, fixes, or releases a planetary gear and its components, in order to reduce the axial dimension, a drum is connected to a specific element of the planetary gear set, which is a rotating member, A band brake is used, which consists of a brake band wound around a drum, one end of which is engaged with the automatic transmission case and the other end is free, and a servo mechanism that displaces the free end of the brake band. Further, when the manual valve is set to the drive<D) position, the specific element of the planetary gear cell i- is automatically activated at the specific gear stage via the brake B2 and the one-way latch F1 connected in series with the brake B2. It is fixed to the transmission case to achieve a specific gear in the high rotation range with relatively low torque, and enables coast driving in the specific gear.
2) or low<L) position, the specific element of the planetary gear set is switched to the automatic transmission via the brake B2 and the one-way latch F1 connected in series with the brake B2 at the specific gear stage. The specific part is fixed to the automatic transmission case by being fixed to the case and engaging the band brake B1, thereby increasing the torque capacity in response to operating conditions such as engine braking driving where the transmitted torque is large. However, when the band brake is engaged at a specific gear (for example, 2nd gear) and released at the preceding and following gears, and the drum rotation direction is set in the opposite direction at the front and rear gears, the intermediate gear When the servo mechanism is actuated to tighten the band in order to achieve the stage, the band is tightened smoothly when the band brake is engaged so that the band tightening direction and the drum rotation direction are in the same direction. When the band brake is engaged in the opposite direction, the band is thrown up, the output shaft torque fluctuates, a shock is generated, the driving feeling is deteriorated, and the life of the band is shortened.

An object of the present invention is to prevent the band of the band brake from jumping up, and to ensure smooth changes in output shaft torque and smooth operation.
To provide a multi-stage automatic transmission for a vehicle and a hydraulic control device that have excellent sensation and can further improve the life of a band.

The multi-stage automatic transmission for vehicles of the present invention has an input shaft, an output shaft, a ring gear connected to the input shaft via a clutch C1, a brake B rotatably supported by the output shaft, and a brake B.
2 and a one-way latch F in series with the brake B2.
1, a carrier connected to the output shaft, and a planetary gear meshed with the ring gear and the sun gear and rotatably supported by the carrier; and a transmission drum connected to the input shaft via a clutch C1 and fixed to the automatic transmission case via a band brake B1, and a sun gear is fixed at a specific gear, and when the specific gear is In the lower gear;
J5, the sun gear rotates in one direction, and in the gears above the specific gear, the sun gear rotates in the opposite direction.In a multi-stage automatic transmission for vehicles, fixing the sun gear in a specific gear is done by braking in one direction. B2 is engaged and the one-way latch F1 is locked, and the opposite direction is engaged by the band brake B1, which is linearly moved in the same direction as the reverse rotation direction.

Next, the present invention will be explained based on embodiments shown in the drawings.

100 is an engine, 200 is a hydraulic 1-lux converter with a direct coupling clutch that is directly connected coaxially to the output of the engine @ 101, and 300 is a three forward speed and one reverse speed converter that is coaxially connected to the output shaft of the torque converter 200. A first underdrive device 400 is an underdrive device 300, and a second underdrive device 500 is arranged in parallel.
is a differential mechanism arranged in parallel with the underdrive device 400.

The torque converter 200 includes a front cover 201 connected to an output shaft 101 of an engine;
00, a pump impeller 202 connected to the torque converter output shaft 203, a turbine runner 204 connected to the torque converter output shaft 203,
Automatic transmission case 600 via one-way clutch 205
a direct coupling clutch 207 that directly couples the stator 206 and output shaft 203 fixed to the front cover 201;
Consisting of

The first underdrive device 300 has an input @301 integrated with the torque converter output shaft 203, and an underdrive device output gear 302 attached to the end,
First and second planetary gear sets 310 and 320 are provided between the input shaft 301 and the output gear 303 disposed coaxially, and are operated by a hydraulic servo to selectively select the components of these planetary gear sets. Multi-disc clutches C1 and C2 and band brake B for engaging, connecting or fixing to achieve a gear position according to vehicle driving conditions.
1. Multi-disc brakes B2 and B3, one-way clutch F1
and F2.

A first planetary gear set 310 arranged next to the input shaft 301 (right side in the figure) includes a ring gear 311 connected to the input shaft 301 via a multi-disc clutch C1, and an output shaft 3.
A band brake B1 is rotatably fitted and supported on the case 600 through a brake B2 and a one-way latch F1 arranged in series with the brake B2, and is arranged in parallel with the brake B2. A sun gear 312 is fixed to the case 600 via a clutch C2, a carrier 313 is connected to the output shaft 303, and a carrier 313 is meshed with the ring gear 311 and the sun gear 312. It consists of a planetary gear 314 rotatably supported by.

As shown in FIG. 2, the band brake B1 includes a transmission drum 330 provided between the outer periphery of the first planetary gear set 310 and the case 600, and one end 341 connected to the case 600.
00, the other end 342 is free and a stopper 343 is fixed, and the brake band 340 is installed through the drum 330, a hydraulic cylinder 351, a hydraulic screw, a ton 352, and a return spring for the screw 1-. 353 and Viton 352, and the tip is connected to the stopper 34 of the band.
A servo mechanism 350 consisting of a rod 354 engaged with
Consisting of

The second planetary gear set 320 includes a sun gear 321 connected to the output @303, a sun gear 322 formed integrally with the sun gear of the first planetary gear set and rotatably supported by the output shaft 4303, and a multi-disc brake. B
3 and the carrier 323 fixed to the automatic transmission case 600 via the one-way clutch F2 provided in parallel with the brake B3, the ring gear 321, and the ring gear 3.
22 and a planetary gear 324 rotatably supported by a carrier 323.

A second underdrive device 400 is configured to drive the output gear 30
An input shaft 40 to which an input gear 401 meshing with 2 is attached.
2 and an output gear 403 rotatably supported by the input shaft 402, a third planetary gear set 410 is provided, and a multi-disc brake that engages, connects, or fixes the components of the planetary gear set. B4, multi-plate clutch C3
, a one-way clutch F3. A third planetary gear set 410 is fixed to the case 600 via a ring gear 411 connected to an input gear 402, a brake B4, and a one-way latch F3 parallel to the brake B4, and output via a clutch C3. It consists of a sun gear 412 connected to a shaft 403 and a carrier 413, the carrier 413, and a planetary gear 414 meshed with the ring gear 411 and sun gear 412 and rotatably supported by the carrier 413.

The differential mechanism 500 includes an input gear j)01 that meshes with the output gear of the second underdrive device 400, a gear box 502 fixed to the input gear, a small differential gear 503, 504, and a differential dog gear 505, 506. and output shafts 507 and 508.

In this multi-stage automatic transmission, when the 1st speed (1st) manual valve is set to the D range, 2 range, or 1 range, the brake '
31. Brake B2 is released, clutch C1 is engaged,
Clutch C2 is released.

Therefore, the tram 330 connected to the sun gear 312 rotates in the opposite direction to the input shaft 301.

2nd speed (2nd) When the manual valve is set to the 0 position, the brake B1 is released and the brake B2 is engaged. This is because the required transmission torque capacity is small and engagement of only brake B2 is sufficient. When the manual valve is set to the 2nd or 1st position, the brake B2 is engaged, and the brake B1 is engaged only when the throttle opening is above the set value, and when the throttle opening is below the set value. The clutch C1 is engaged and the clutch C2 is released. drum 3
30 is stopped.

3rd speed (3rd) Brake B1 is released, brake B2 is engaged, and clutch C1 and clutch C2 are engaged, so the drum 330
rotates integrally with the input shaft 301 in the same direction. In the 3-2 downshift when the manual valve is set to the 2nd position, the band brake B1 that is engaged is set to the 2nd position.
From the state where the drum 330 is rotating in the same direction as the input shaft 301 as shown by arrow A in the figure, the free end 3 of the band 340
42 is rotated and displaced in the forward direction, the tightening of the drum 330 is stopped, so that the drum 330 is smoothly engaged.] Hertz changes smoothly, but in the 1-2 upshift, as shown in FIG. The direction in which the drum 330 is rotating as shown by arrow B and the servo mechanism 3! The direction in which the band free end is pressed by +0 is reversed, and vibration occurs between the rod 341 and the band free end 342, causing fluctuations in torque. Therefore, at the 1-2 upshaft 1 moment, the drum 330 is stopped by the brake B2 and the one-way latch F1.
By doing this, it is possible to prevent the torque from fluctuating.

Since this 1-2 upshift occurs during acceleration, the thrower 1-2 opening is large and the vehicle is in an engine drive state, so the one-way latch F1 is locked, and the drum 330 can be stopped by the brake B2. Tonaru.

In addition, when the manual valve is set to the 2nd position, the 3-2 downshift is coasting, the throttle opening is 0 or small, the one-way clutch F1 is in a free state, and the brake B1 is used to stop the drum 330. engagement is essential.

FIG. 3 shows a hydraulic control device that controls the multi-stage automatic transmission for a vehicle shown in FIG. 1 according to vehicle running conditions.

This hydraulic control device includes an oil strainer 10, an oil pump 11, a primary regulator valve 12, a secondary regulator valve 13, a throttle valve 14, a kickdown valve 15, a cutback valve 17, a throttle modulator pressure 18, an accumulator control valve 19, and a manual valve. 30.2-3 shift valve 31.1-2 shift valve 33.
3-4 shift valve 35, low coast modulator valve 37
．． 2nd course 1 ~ Modulator valve 39, overdrive sequence valve 41, governor valve 43, band brake control valve 45, lockup signal valve 91, lockup control valve 93, accumulator 51, 52, 53, relief valve 61, cooler bypass valve 62, an electromagnetic solenoid valve 71 for overdrive sequence control, a flow control valve formed by combining a check valve material orifice and an orifice, a check valve, and orifices inserted in various places in the oil passage.

The oil pump 11 is driven by the engine, sucks hydraulic oil from the oil reservoir through the oil strainer 10, and discharges the pressure oil into the oil passage 1.

The primary regulator valve 12 has a spring 1 on one side.
21 loaded with the spool 120, and the spool 120
The regulator plunger 110 is connected in series to the spring 121 side of the regulator plunger 110 . The spool 120 has an orifice 8
The regulator plunger 110 includes a land 125 at an upper end (the upper end in the figure, the same applies hereinafter) that receives feedback of the output hydraulic pressure via the oil passage 5, and a large-diameter two-side land 115 that receives line pressure input from the oil passage 5; The regulator plunger 110 is provided with a small-diameter lower land 117 to which the thrower modulator pressure is applied from the passage 9B. The receiving force presses the spool 120 upward, and as a result, the spool 120 receives the spring load of the spring 121 from one side and the pressing force from the plunger 110, and receives the output oil pressure (line pressure of oil passage 1) fed back from the other side. ) is displaced, and adjusts the communication area between oil passage 1 and oil passage 6 to adjust the oil pump discharge pressure of oil passage 1 to the line pressure corresponding to the input oil pressure and supply surplus oil to oil passage 6. Furthermore, unnecessary surplus oil is drained from the drain port 124. The drained oil returns to the oil reservoir via the oil passage 8.

The secondary regulator valve 13 has a spring 1 on one side.
31 is provided with a spool 130. The spool 130 receives the throttle pressure applied to the land 135 via the oil passage 9 from one side and the spring load from the spring 131, and receives the output oil pressure (from the oil passage 6) from the other side to the upper end land 133 via the orifice 802. hydraulic pressure), and the oil passage 6 is displaced according to these input hydraulic pressures.
The area of communication between the lubricating oil supply oil passage 6E and the drain oil passage 6D is adjusted, the secondary pressure of the oil passage 6 is regulated to the fluid coupling operating oil pressure, the lubrication oil pressure of the oil passage 6E is regulated, and excess oil is transferred to the oil passage. Discharge to 6D. The oil discharged into the oil path 6D flows into the oil reservoir. Further, the lubricating oil supplied to the oil passage 6F is supplied to parts requiring lubrication.

The throttle valve 14 has a spring 141 loaded on one side, and includes a spool 140 having a large diameter land 142, a medium diameter land 143, and a small diameter land 144.

The spool 140 receives a spring load from the spring 141 from one side, a pressure-receiving area that is the difference in area between the lands 142 and 143, and a feedback hydraulic pressure of the output hydraulic pressure manually applied via the orifice 715 (throttle pressure of the oil passage 9). , land 143 and land 1 are inputted via oil passage 9A.
The cutback pressure from the cutback valve 17 whose pressure receiving area is the area difference between the spool 14 and the cutback valve 17 is received from the other side of the spool 14.
0 and the kickdown valve 15 connected in series via a spring 151, the kickdown valve 15 is displaced in response to a pressing force corresponding to the amount of depression of the throttle pedal, etc. , the line pressure supplied from the oil passage 1 is regulated according to the throttle opening degree, etc., and outputted to the oil passage 9 as throttle pressure.

The kickdown valve 15 has a spool 150, which is linked to a throttle pedal, moves under pressure from a throttle cam 152 that rotates in accordance with the amount of depression of the pedal, and moves via a spring 151 in response to the amount of depression of the pedal. Throttle pressure is generated by transmitting the pressing force to the spool 140. In addition, the spool 150 is pressed upward in the figure by a cutback pressure input from the oil passage 9A between the large-diameter upper end land 153 and the small-diameter lower end land 155 with a pressing force according to the throttle opening and the cutback pressure, It has the role of reducing the load when pressing the pedal.

The cutback valve 17 has a first land 17A that receives governor pressure from one side via the oil passage 6, and a small-diameter second land 17B that receives throttle pressure from the other side via the oil passage 9. A spool 170 is provided which receives throttle pressure from the oil passage 9 using the area difference between the first land 17A and the second land 17B as an effective pressure receiving area. When the governor pressure is high, the spool 170 is set downward in the drawing, connects the oil passage 9 and the oil passage 9A, and outputs cutback pressure from the oil passage 9A.

The throttle modulator 18 has a spring 181 on one side.
The spool 180 has a spool 180 loaded with
receives the spring load of the spring 181 from one side and the throttle pressure applied from the oil passage 9 using the area difference between the intermediate land 183 and the lower end land 185 as an effective pressure receiving area, and receives the large diameter land 187 from the other side via the orifice 804. The throttle pressure applied from the oil passage 9' through the oil strainer 603 is displaced in response to the feedback of the throttle modulator pressure in the oil passage 9B. Output as .

The accumulator control pressure 19 has a spool 190 loaded with a spring 191 on one side. The spool 19 receives the applied throttle modulator pressure from the other side through the orifice 805.
The upper end land 197 of 0 is displaced in response to feedback of the accumulator control pressure which is the output oil pressure, regulates the line pressure supplied from the oil passage 1, and outputs it to the oil passage 1K as the accumulator control pressure.

The manual valve 30 is a shift lever installed in the driver's seat.
A spool 300 interlocked with the spool 300 is provided. The spool is P(
Park), R (reverse), N (neutral), D (drive), S (second), and L (low). The passage 1 is connected to the oil passages 2 to 5.

Table 1 1-2 shift valve 31. 2-3 shift valve 33. 3-4 shift valve inputs governor pressure and throttle 1 to 3 pressure, and also outputs low coast modulator pressure and 2nd It is equipped with a spool that is displaced by inputting the 211d coast modulator pressure output from the coast modulator valve and the sequence pressure output from the overdrive sequence valve, and connects the oil passage 2.3.4 with a predetermined hydraulic servo. Adjust according to vehicle speed.

The 2nd coast modulator valve 3 lowers the line pressure of the oil line 3 by a predetermined pressure (level down) and the shift lever
The hydraulic pressure supplied to the hydraulic servo of the frictional engagement element (handbrake Bl) that is engaged when the handbrake is shifted to the second position is lowered by a predetermined pressure from the line pressure.

The band brake control valve 45 has a small diameter land 46 on one side.
1. Large diameter land 463 on the other side, medium diameter land 4 in the middle
65 is provided, and a spring 47 is provided on the land 461 side of the spool. In the spool 4G, the line pressure of the oil passage 2 is applied to the small diameter land 461, the throttle pressure of the oil passage 9 is applied to the large diameter land 463, and the spool 4G is displaced by these input oil pressures and the spring load of the spring 47, Hydraulic servo of band brake B1 [Out ports 1 to 453 that communicate with communication oil passage 30 to 3-1, oil passage 3.2 "1d coast modulator valve 39, oil passage 3A, 2-3 shift valve 31, Oil road 3B, 1
- Control communication with the inboard 451 and drain boat 455 to which the hydraulic pressure reduced by the 2nd coast modulator valve 39 is supplied to the inboard 451 via the 2nd shift valve 33 and the oil path 3D. .

The spool 4G is displaced to the left in the figure when the throttle pressure of the oil passage 9 is higher than the set value, and the oil passage 3E is moved to the drain boat 45.
5, the hydraulic servo B-1 is exhausted and the band brake B1 is released. As shown in Table 1, line pressure is generated in the oil passage 3 when the manual valve 30 is set to the 2nd and 2nd positions, and as shown in Table 2, the brake B1 supplies pressure oil to the hydraulic servo 3-1 in the second speed is supplied and engaged, and the hydraulic servo 3-1 is discharged and released in modes other than the first and second speeds. When the vehicle is running in 3rd gear and accelerating, the throttle opening increases due to kickdown, and as a result, the throttle pressure increases, brake B1 is released. Conversely, when the vehicle is coasting and the throttle opening is small, the throttle opening becomes large due to kickdown.
When a downshift is made, brake B1 is engaged and the free end 34 of the brake band of band brake B1
The direction of displacement of the drum 330 is the same as the direction of rotation of the drum 330, and the band brake B1 is smoothly engaged. Furthermore, when a 1-2 upshift is performed during acceleration, the hydraulic servo B-i of the brake B1, whose opening degree is increased by the depression of the throttle pedal, is exhausted by the action of the band brake control valve, Similarly to when the manual valve is set to the D range, the brake B2 is engaged, and the band brake is prevented from jumping up.

When the throttle pressure of oil path 9 is below the set value, spool 4
6 is displaced to the right in the drawing, the oil passage 3E is connected to the oil passage 3D, and the hydraulic servo B-1 is supplied with 21]d coast modulator pressure, and the band brake B1 is engaged.
The accumulator 51 communicates with the oil passage 2 via a flow rate control valve 811, and the hydraulic servo C-1 of the clutch C1.
Several lines are connected to the oil passage 2G, which connects to the accumulator 52.
is the oil passage 2 that communicates with the oil passage 2 via the 2-3 shift valve 31.
The accumulator 53 is connected to the oil passage 2P via the flow control valve 812 and the oil passage 2Q which also communicates with the hydraulic servo C-2 of the clutch C2. The hydraulic servo B-2 of the brake B2 is connected to the oil passage 2A connected to the hydraulic servo B-2 of the brake B2 via a flow rate control valve 813.

These accumulators, together with flow control valves, adjust the pressure rise rate of the hydraulic pressure generated in the name, so that the pressure rise characteristics of the hydraulic pressure supplied to each hydraulic servo are appropriately controlled, and the engagement of the clutch or brake is performed smoothly. The timing of engagement is adjusted. Also, the spools of accumulators 51, 52 and 53 are connected to oil path 1.
The accumulator control pressure, which is the output oil pressure of the accumulator controller 1 to the roll valve 19, is input as back pressure from K and is zeroed. The lock-up signal valve 91 has a spool 910 with a spring 911 installed in front of it on one side, and the spool is operated by receiving the spring load of the spring 910 from one side and by receiving the governor pressure of the oil passage 7 from the other side. .

When the governor pressure of the oil passage 7 is high, the spool 91 is set to the upper side in the diagram to connect the oil passage 2N and the oil passage 2D, and when the governor pressure is low, the spool 91 is set to the lower part in the diagram to connect the oil passage 2D to the drain boat. Call 915. Also, the spool 910 is 3-4
When the oil pressure of the oil passage 1J communicating with the oil passage 7 via the shift valve 35 is applied to the upper end land 913 in the drawing in the same direction as the spring movement of the spring 911, the land 913 is fixed downward in the illustration.

The lock-up clutch control valve 93 has a small-diameter plunger 932 and a spool 930 inserted in series with the plunger 932, and the spool 930 is constantly supplied with voltage from one side through the oil passage 1 via the plunger 932. The input oil pressure (line pressure) from the oil passage 2D is received from the other side to the lower end land 937 in the figure, and the input oil pressure is displaced. When oil pressure is generated in the oil passage 2D, the spool 930 is set upward in the figure, so that the oil passage 6 and the oil passage 6B are in communication, and the oil passage 6A and the drain port 933 are in communication,
When the direct coupling clutch 207 is engaged and the pressure in the oil passage 2D is exhausted, the spool 930 is set to the lower side, so that the oil passage 6 and the oil passage 6A communicate with each other, and the oil passage 6B communicates with the cooler circuit 6C. .

The cooler bypass valve 62 is provided in the cooler circuit 6C, and leaks pressure oil to protect the oil cooler when the oil pressure in the cooler circuit 6c exceeds a set value.

This hydraulic control device is controlled by the manual valve setting position made by the vehicle driver and the governor pressure and throttle pressure.
-2 shift valve 33. The spool of the 3-4 shift valve 35 is controlled to automatically shift the automatic transmission shown in FIG. 1 to four forward speeds and one reverse speed as shown in Table 2.

Table 2 In Table 2, ○ indicates the engaged state of the clutch or brake and the locked state of the one-way clutch, × indicates the released state of the clutch or brake, and the free state of the one-way clutch, and ◎ indicates the state of the throttle open. It is engaged when the degree is below the set value, and released when it is above the set value. △ indicates that the one-way clutch is free when coasting and locked when driving with engine drive.

Next, the operation of the hydraulic control system for the automatic transmission of this embodiment at the setting (shift) position of each manual valve will be explained.

b) When shifting to manual valve 30@D range.

As shown in Table 1, hydraulic pressure is supplied to the oil passage 2, and line pressure is thereby supplied via the flow rate control valve 801 and the oil passage 2C, and the clutch C1 is engaged. Running in 1st gear is 1-2
The spool 330 of the shift valve 33 is located on the lower side, the oil passages 3D and 2A that communicate with the brakes B1 and B2 are exhausted, and no oil pressure is supplied to the oil passage 5C that communicates with the brake B3, so the brakes 81 and B2 .83 has been released. When the vehicle speed reaches a preset value, the governor pressure in the oil passage 7, which is the control oil pressure for the 1-2 shift valve, increases.
The spool 330 of the 1-2 shift valve 33 moves upward,
Oil path 2.1-2 shift valve 33, oil path 2A, flow control valve 8
13. Hydraulic pressure is supplied through the oil path 2B, and the brake B2 is engaged to perform a shift to the second speed. At this time, the 3-4 shift valve is fixed at the lower side by the oil pressure of the oil passage 2N communicating with the oil passage 2 via the overdrive sequence valve 41, so it is fixed at the 3rd speed state. Upshifting to third gear is performed when the vehicle speed, throttle opening, etc. reach predetermined values, the spool 310 of the 2-3 shift valve 31 moves upward, and the oil passage 2A, the 2-3 shift valve 31, and the oil Hydraulic pressure is supplied through passage 2P, flow rate control valve 812, and oil passage 2Q to clutch C.
2 engages, and at the same time the spool 33 of the 1-2 shift valve 33
0 is fixed to the upper side (second speed, third speed, and fourth speed side). Upshifting to 4th gear is the same as above, when the spool 350 of the 3-4 shift valve moves to the left, pressure is discharged from the oil passage 1D, oil pressure is supplied to the oil passage 1R, and the brake B4 is released. This is done by engaging clutch C3.

口) When the manual valve 30 is in the 2nd range.

As shown in Table 1, line pressure is supplied to oil passage 3 in addition to oil passage 2. 1st, 2nd, and 3rd gears are shifted in the same manner as in the above D range, but line pressure is applied to the spool of the 3-4 shift valve via oil line 2, overdrive shift valve 41, and oil line 2 N@. Since the voltage is applied and the spool 350 is fixed at the lower side, no shift to fourth gear occurs. This 3-2
When a downshift occurs, oil passage 3, three low coast modulator valves, 2-3 shift valve 31, oil passage 3A, 1-
The low coast modulator pressure is supplied to the hydraulic servo B-1 of the brake B1 through the 2-shift valve 33 and the oil passage 3D, and the brake B1 is engaged to obtain the second speed in which engine braking is effective.

c) When the manual valve 30 is set to the L position.

In addition to the oil passages 2 and 3, line pressure is also supplied to the oil passage 4. The second speed is the same as when the manual valve is in the D range, and the spool 310 of the 2-3 shift valve 31 is fixed at the lower side. Further, in the first speed, the oil passage 4, the low coast modulator valve 37, and the oil passage 4A.

1-2 The low coast modulator pressure is supplied to the hydraulic servo B-3 of the brake B3 through the shift valve 33 and the oil path 4B, and the brake B3 is engaged and the engine brake is applied.
It is designed to provide speed.

e) When the manual valve is set to the R position.

Oil passage 1 and oil passage 5 communicate, and oil passages 3 and 4 are depressurized and become 2-3.
Since the spool of the shift valve 31 is set at the lower side and line pressure is generated in both oil passages 1B and 1A, the spools 330 and 350 of the 1-2 shift valve 33 and the 3-4 shift valve 35 are both fixed at the lower side. , clutch C2, brake B3, and brake B4 are engaged to obtain a reverse traveling state.

As described above, the multi-stage automatic transmission for vehicles of the present invention has an input shaft, an output shaft, and a clutch c1 connected to the input shaft. A J-connected ring gear, rotatably supported by the output shaft, and a sun gear fixed to the automatic transmission case via a brake B2 and a one-way latch F1 connected in series with the brake B2, and a sun gear connected to the output shaft. A planetary gear set consisting of a planetary gear meshed with gear A7, a ring gear and a sun gear, and rotatably supported by a carrier, and connected to the sun gear and connected to the input shaft via a clutch C1, and A transmission drum is fixed to the automatic transmission case via a band brake B1, and the sun gear is fixed at a specific gear, and at the specific gear, the sun gear rotates in one direction at a gear on the lower side of the gear. In a multi-stage automatic transmission for a vehicle in which the sun gear rotates in the opposite direction at a gear on the high-speed side of the specific gear, the sun gear is fixed in the specific gear by engaging the brake B2 on the one rotation direction. This is done by locking the one-way latch F1, and in the opposite rotation direction by engaging the band brake B2 which is fibrillated in the same direction as the reverse rotation direction, so that the band of the band brake does not bounce. The change in output shaft torque is smooth, providing excellent driving sensation and improving the life of the band. Further, by providing a band brake control valve in the hydraulic control device, it is possible to reliably prevent the band brake from jumping up with a simple configuration.

[Brief explanation of drawings]

FIG. 1 is a skeletal diagram of an automatic transmission, FIG. 2 is a sectional view of a band brake, and FIG. 3 is a circuit diagram of a hydraulic control device for an automatic transmission according to the present invention.

Claims (1)

[Claims] 1) An input shaft, an output shaft, a ring gear connected to the input shaft via a clutch C1, a brake B2 rotatably supported by the output shaft, and a ring gear connected in series with the brake B2. A planetary gear consisting of a sun gear fixed to the automatic transmission coupe via a one-way latch F1, a carrier connected to the output shaft, and a planetary gear meshed with the ring gear and the sun gear and rotatably supported by the carrier. and a band brake B that is connected to the sun gear and to the input shaft via the clutch C1.
1, the sun gear is fixed at a specific gear, and the sun gear rotates in one direction at a lower gear of the specific gear. In multi-stage automatic transmissions for vehicles in which the sun gear rotates in the opposite direction at the gear on the high-speed side of the gear, the sun gear is fixed at a specific gear by engaging brake B2 in one direction and engaging latch F1 in one direction. A multi-stage automatic transmission for a vehicle, characterized in that the transmission is performed in the opposite direction by engagement of a band brake B1 whose free end is displaced in the same direction as the reverse rotation direction. 2) an input shaft; a ring gear connected to the output shaft and the input shaft via a clutch C1 operated by a hydraulic servo;
A sun gear fixed to the automatic transmission case is connected to the output shaft through a brake B2 rotatably supported by the output shaft and operated by a hydraulic servo, and a one-way latch F1 connected in series with the brake B2. a carrier, and a planetary gear set consisting of a planetary gear that is rotatably supported by the carrier and in mesh with the ring gear and the sun gear, and a hydraulic servo connected to the sun gear and connected to the input shaft via the clutch C1. and a transmission drum fixed to the automatic transmission case via a band brake B1 operated by the transmission drum, the sun gear is fixed at a specific gear, and the sun gear is unidirectional at a gear on the low speed side of the specific gear. In a hydraulic control system for a multi-stage automatic transmission for a vehicle, the sun gear rotates in the opposite direction at a gear on the high-speed side of the specific gear. , a band brake control valve is inserted that is controlled by a throttle pressure that changes in relation to the throttle opening degree, and the band brake control valve controls the brake B- when the throttle pressure is higher than the set value at the specific gear stage. 1 to release the brake B1, and when the throttle pressure is below the set value, the brake 3-1 and the hydraulic pressure source are connected to engage the brake B1, thereby fixing the sun gear at a specific gear. One direction is achieved by engaging the brake B2 and locking the one-way latch F1, and the opposite direction is achieved by engaging the band brake B1 whose free end is displaced in the same direction as the reverse rotation direction. Hydraulic control system for multi-stage automatic transmissions for vehicles. 3) The hydraulic pressure of the multi-stage automatic transmission for a vehicle according to claim 1 or 2, wherein the specific gear is the second forward speed when the manual valve is set to the 2nd position. Control device.