JPH0231263B2 - - Google Patents

Description

[Detailed description of the invention]

<Industrial Application Field> The present invention relates to a hydraulic control device for an automatic transmission for a vehicle, and particularly to a hydraulic control device for an automatic transmission capable of multi-stage shifting of five or more forward speeds. <Conventional technology> Conventionally, in order to improve the durability and quietness of the engine during high-speed driving of a car, the gear ratio of the highest gear has been changed so that the rotation of the engine is relatively low during high-speed driving of a car. The transmission output shaft is overdriven so that the rotation is higher than the engine rotation, and the interval between the gear ratios of each gear is set so that the engine rotation does not become high even when each gear is used during acceleration or deceleration. The idea was to make it narrower. Then, the output member of the conventional main gear transmission mechanism that achieves three forward speeds is further shifted by an auxiliary gear transmission mechanism that achieves two forward speeds disposed at the rear to obtain a gear ratio of six forward speeds. A so-called multi-gear transmission mechanism is disclosed in Japanese Patent Publication No. 51-31334. <Problems to be Solved by the Invention> By the way, as shown in Japanese Patent Publication No. 51-31334, a main gear transmission mechanism that achieves three forward speeds and a sub-gear transmission mechanism that achieves two speeds are arranged in series. When the auxiliary gear transmission mechanism is shifted at each gear stage of the main gear transmission mechanism to obtain the gear ratio of six forward gears of the multi-stage gear transmission mechanism, each of the six forward gears of the multi-stage gear transmission mechanism The gears of the main gear transmission mechanism and the auxiliary gear transmission mechanism are as shown in the table below.

[Table] When the multi-stage gear transmission mechanism is in the 2nd forward speed, the main gear transmission mechanism is in the 1st speed state, and the auxiliary gear transmission mechanism is in the 2nd speed (overdrive) state.When the multi-stage gear transmission mechanism is in the 3rd forward speed, the main gear transmission mechanism is in the 2nd speed (overdrive) state. The transmission mechanism is in the 2nd speed state, and the auxiliary gear transmission mechanism is in the 1st speed (directly connected) state, and when the multi-stage gear transmission mechanism shifts from forward 2nd speed to 3rd speed, both the main gear transmission mechanism and the auxiliary gear transmission mechanism are in the 2nd speed state. The second gear shift is performed, and the second forward shift of the multi-gear transmission mechanism is performed.
A shift from the first gear to the third gear is achieved. Furthermore, when the multi-stage gear transmission mechanism is in the fourth forward speed, the main gear transmission mechanism is in the second speed state, and the auxiliary gear transmission mechanism is in the second speed (overdrive) state, and when the multi-stage gear transmission mechanism is in the fifth forward speed, the main gear transmission mechanism is in the second speed state (overdrive). The mechanism is in 3rd speed, the auxiliary gear transmission mechanism is in 1st speed (directly connected),
When the multi-stage gear transmission mechanism shifts from the fourth forward speed to the fifth speed, both the main gear transmission mechanism and the auxiliary gear transmission mechanism are shifted, and the multi-stage gear transmission mechanism shifts from the fourth forward speed to the fifth speed. This results in a speed change of . That is, from 2nd speed to 3rd speed and 4th speed of the multi-stage gear transmission mechanism.
During the two shifts from speed to fifth speed, both the main gear transmission mechanism and the auxiliary gear transmission mechanism are changed. At this time, if a time lag occurs between the shift timing of the main gear transmission mechanism and the shift timing of the auxiliary gear transmission mechanism, for example, if the auxiliary gear transmission mechanism shifts after a predetermined period of time has passed after the main gear transmission mechanism has shifted, Shifting is performed twice in a short period of time, and the shift shock due to so-called double shifting becomes large. Therefore, in such a case, it is necessary to synchronize the speed change of the main gear transmission mechanism and the speed change of the auxiliary gear transmission mechanism. For example, in the case described above, it is necessary to synchronize the speed change of the auxiliary gear transmission mechanism, which changes gears at each gear stage of the main gear transmission mechanism, with the speed change of the main gear transmission mechanism. By the way, according to the structure disclosed in Japanese Patent Publication No. 51-31334, the auxiliary gear transmission mechanism is disposed at the rear of the main gear transmission mechanism, and the output member of the main gear transmission mechanism is further connected to the auxiliary gear disposed at the rear. The transmission mechanism is configured to change the speed to obtain six forward gear ratios of the multi-gear transmission mechanism. Since the auxiliary gear transmission mechanism needs to transmit torque from 1st to 3rd gear of the main gear transmission mechanism, the frictional engagement element of the auxiliary gear transmission mechanism transmits the transmitted torque of 1st gear, which is in a large deceleration state. It requires a large torque capacity that can be sufficiently transmitted. When attempting to synchronize the speed changes of the auxiliary gear transmission mechanism and the main gear transmission mechanism, if the torque capacity of the friction engagement element of the auxiliary gear transmission mechanism is too large, the speed change of the auxiliary gear transmission mechanism tends to be delayed. Shift shock occurs due to double shifting. For example,
When the multi-stage gear transmission mechanism shown in Publication No. 31334 shifts from the second forward speed to the third forward speed, the brake 17 of the main gear transmission mechanism is released and the brake 16 is engaged, and the auxiliary gear transmission mechanism brake 19
is released, and the clutch 18 is engaged. However, if the brake 19 is designed to have a large torque capacity, the release of the brake 19 will be delayed, so the release of the brake 17 and the engagement of the brake 16 of the main gear transmission mechanism will be delayed. Rear, brake 1 of the auxiliary gear transmission mechanism
9 and engagement of the clutch 18, resulting in a double shift and a shift shock. Therefore, the present invention solves the above-mentioned problem by arranging the auxiliary gear transmission mechanism in front of the main gear transmission mechanism and connecting the output shaft of the auxiliary gear transmission mechanism to the main gear transmission mechanism. The transmission torque capacity of the frictional engagement element of the auxiliary gear transmission mechanism can be set to a small value, and the auxiliary gear transmission mechanism is changed in each shift state of the main gear transmission mechanism by combining the main gear transmission mechanism and the auxiliary gear transmission mechanism. The object of the present invention is to provide a multi-stage gear transmission mechanism that can easily synchronize the speed changes of the main gear transmission mechanism and the auxiliary gear transmission mechanism in a type of automatic transmission. <Means for Solving the Problems> A hydraulic control device for an automatic transmission according to the present invention includes a hydraulic torque converter, a single-row planetary gear device connected to the output shaft of the hydraulic torque converter, and the planetary gear device. a front-type sub-gear transmission mechanism that achieves two forward speeds and has a frictional engagement element consisting of a clutch that connects two elements of the planetary gear and a brake that fixes one element of the planetary gear; and the sub-gear. An automatic transmission comprising a main gear transmission mechanism that is connected to an output shaft of the transmission mechanism and has a plurality of frictional engagement elements and a two-row planetary gear unit and achieves three forward speeds, comprising: a hydraulic source; A line pressure regulating valve that adjusts the oil pressure from the source to line pressure, a speed selection valve that manually switches the gear range, and a line pressure supplied to each frictional engagement element of the main gear transmission mechanism are switched to move forward 3. first and second shift valves achieving stages;
a third shift valve that switches the line pressure supplied to each frictional engagement element of the auxiliary gear transmission mechanism to achieve two forward speeds; and a first shift valve that controls the first, second, and third shift valves, respectively. , second and third solenoid valves, and a multi-stage speed change is obtained by combining each speed change of the main gear transmission mechanism and each speed change of the auxiliary gear transmission mechanism. <Operations and Effects of the Invention> According to the present invention, in an automatic transmission of a type in which a main gear transmission mechanism and an auxiliary gear transmission mechanism are combined to change the speed of the auxiliary gear transmission mechanism in each shift state of the main gear transmission mechanism, By arranging the gear transmission mechanism at the front of the main gear transmission mechanism and connecting the output shaft of the auxiliary gear transmission mechanism to the input shaft of the main gear transmission mechanism, the transmission torque capacity of the frictional engagement element of the auxiliary gear transmission mechanism can be increased. can be set to a small value, so there is an effect that the speed change of the main gear transmission mechanism and the speed change of the auxiliary gear transmission mechanism can be easily synchronized without delaying the speed change of the auxiliary gear transmission mechanism. For example, when shifting from the second forward speed to the third forward speed of an automatic transmission, the brake 40 of the main gear transmission mechanism is engaged, and the brake 19 of the auxiliary gear transmission mechanism is released and the clutch 12 is engaged. , since the torque capacity of the brake 19 is designed to be small,
Since the release of the brake 19 is not delayed, the engagement of the brake 40 of the main gear transmission mechanism, the release of the brake 19 of the auxiliary gear transmission mechanism, and the clutch 12 are not delayed.
This has the effect of making it easier to synchronize the engagement of the two gears and preventing shift shocks due to double gear shifting. In addition, the line pressure supplied to each friction engagement element of the main gear transmission mechanism is switched to the first and second shift valves that achieve three forward speeds, and the line pressure is supplied to each friction engagement element of the auxiliary gear transmission mechanism. By providing the first, second, and third solenoid valves that independently control the third shift valve that switches the line pressure and achieves two forward speeds, the shift of the main gear transmission mechanism and the third shift valve that achieves two forward speeds are provided. Brake 1 by making the mating element more compact
This has the effect of easily controlling the synchronization with the speed change of the auxiliary gear transmission mechanism, which shortens the release time of No. 9, and achieving so-called multi-stage operation. <Example> Next, the present invention will be explained based on an example shown in the drawings. FIG. 1 is a schematic diagram showing an example of a planetary gear mechanism of a hydraulic six-speed automatic transmission with an overdrive mechanism. This automatic transmission is equipped with a torque converter 1, an overdrive mechanism 2, and a planetary gear transmission mechanism 3 with three forward speeds and one reverse speed, and is controlled by a hydraulic circuit device as shown in FIG. There is.
The torque converter 1 is a well-known type that includes a pump 5, a turbine 6, and a stator 7. The pump 5 is connected to an engine crankshaft 8, and the turbine 6 is connected to a turbine shaft 9. The torque converter 1 also includes a direct coupling clutch 5 that mechanically connects the engine crankshaft 8 and the turbine shaft 9 without fluid.
0 is set. The turbine shaft 9 constitutes the output shaft of the torque converter 1, which also serves as the input shaft of the overdrive mechanism 2, and is connected to a carrier 10 of a planetary gear system in the overdrive mechanism. A planetary pinion 14 rotatably supported by a carrier 10 meshes with a sun gear 11 and a ring gear 15.
A multi-plate clutch 12 and a one-way clutch 13 are provided between the sun gear 11 and the carrier 10.
Further, a multi-disc brake 19 is provided between the sun gear 11 and a housing or overdrive case 16 containing the overdrive mechanism. The ring gear 15 of the overdrive mechanism 2 is the input shaft 2 of the planetary gear transmission mechanism 3 with three forward speeds and one reverse speed.
It is connected to 3. A multi-disc clutch 24 is provided between the input shaft 23 and the intermediate shaft 29, and a multi-disc clutch 25 is provided between the input shaft 23 and the sun gear shaft 30. A multi-disc brake 26 and a multi-disc brake 40 via a one-way clutch 41 are provided between the sun gear shaft 30 and the transmission case 18 . The sun gear 32 provided on the sun gear shaft 30 includes a carrier 33, a planetary pinion 34 supported by the carrier,
The ring gear 35 meshing with the pinion, another carrier 36, the planetary pinion 37 supported by the carrier, and the ring gear 38 meshing with the pinion constitute a two-row planetary gear device. Ring gear 35 in one planetary gear device
is connected to the intermediate shaft 29. Further, the carrier 33 in this planetary gear device is connected to a ring gear 38 in the other planetary gear device, and these carrier and ring gear are connected to an output shaft 39. Further, a multi-disc brake 27 and a one-way clutch 28 are provided between the carrier 36 and the transmission case 18 in the other planetary gear set. Such a hydraulic automatic transmission with an overdrive device engages or releases each clutch and brake according to the engine output and vehicle speed by a hydraulic circuit device, which will be explained in detail below. It is designed to perform six forward speeds including D) or two reverse speeds by manual switching. Table 1 shows the transmission gear position and the operating status of the clutch and brake.

[Table] Here, ◯ indicates that each clutch and brake are in an engaged state, and × indicates that they are in a released state. Next, the clutch and brake 12, 19,
The hydraulic circuit of the control device of the present invention, which selectively operates the gears 24, 25, 26, 27, and 40 to perform an automatic or manual speed change operation, will be described based on an embodiment shown in FIG. The hydraulic circuit includes an oil reservoir 100, an oil pump 101,
Pressure regulating valve 102, second pressure regulating valve 103, throttle valve 200, cut pack valve 201, manual valve 210, first shift valve 220, second shift valve 230, third shift valve 240, coast modulator valve 250, an accumulator 260 for smoothly engaging the clutch 24, an accumulator 270 for smoothly engaging the clutch 25, an accumulator 280 for smoothly engaging the brake 40, and a lock-up control valve. 290, bypass valve 300, flow control valve with check valve 310, 320, 330, 340, 350,
360, 370, 502, a check valve 380, a relief valve 390, a second solenoid valve 400 that controls the second shift valve 230, a third solenoid valve 410 that controls the shift valve 240, and a lock-up control valve 290. The fourth solenoid valve 420, the first solenoid valve 430 that controls the first shift valve 220, and the hydraulic servos 12A, 19A, 24A, 25A, 25 between each valve, clutch, and brake.
Consists of oil passages connecting B, 26A, 27A, 27B, and 40A. Hydraulic oil pumped up from an oil reservoir 100 by an oil pump 101 is adjusted to a predetermined oil pressure (line pressure) by a pressure regulating valve 102 and supplied to an oil path 104. Excess oil from the pressure regulating valve passes through the oil passage 105 to the second
The pressure is regulated to predetermined torque converter pressure, lubricating oil pressure, and cooler pressure in accordance with the throttle pressure of throttle valve 200 that is supplied to pressure regulating valve 103 and guided through oil passage 124 . A manual valve 210, which is connected to the oil passage 104, is connected to a shift lever and is manually operated to move to P, R, N, D, I, and L positions according to the range of the shift lever. Table 2 shows the oil passage 10 at each shift lever position.
4 and oil passages 106 to 110 are shown. 〇 indicates that there is communication.

[Table] The first solenoid valve 430 that controls the first shift valve closes the valve port 431 when not energized and generates hydraulic pressure in the oil passage 501 that communicates with the oil passage 104 via the orifice 432, and when energized Valve port 431
is opened to discharge the pressure oil in the oil passage 501 from the discharge port 433. a second control valve that controls the second shift valve 230;
When the solenoid valve 400 is de-energized, the valve port 40 is closed.
1 is closed to generate oil pressure in the oil passage 111 that communicates with the oil passage 107 via the orifice 402, and when energized, the valve port 401 is opened and the oil passage 11 is discharged from the discharge port 403.
Drain the pressure oil from step 1. The third solenoid valve 410 that controls the third shift valve 240 closes the valve port 411 when not energized to generate oil pressure in the oil passage 112 that communicates with the oil passage 104 via the orifice 412, and closes the valve port 411 when energized. Open and discharge port 413
The pressure oil in the oil passage 112 is discharged from the oil passage 112. Fourth solenoid valve 4 controlling lock-up control valve 290
20 is an oil passage 1 which closes the valve port 421 and communicates with the oil passage 104 via the orifice 424 when the current is not energized.
14, and when energized, the valve port 421 is opened and the pressure oil in the oil path 114 is discharged from the discharge port 423. Table 3 shows the relationship between energization and de-energization of the solenoid valves 400, 410, and 430 and the gear state of the automatic transmission.

[Table] The first shift valve 220 has a spring 2 on one side.
The first and second spools 222 are provided with
At high speed, the solenoid valve 430 is de-energized and the oil passage 50 is
Oil pressure is generated in the oil passage 110, oil passage 113, and oil passage 131.
and the oil passage 132, and in the third, fourth, fifth, and sixth speeds, the solenoid valve 430 is energized and the pressure oil in the oil passage 501 is discharged, so that the spool 222
is set on the right side in the figure, and oil passage 106 and oil passage 11
3. Connect the oil passage 110 and the oil passage 132, and the oil passage 131 and the oil passage 133, respectively. The second shift valve 230 has a spring 23 on one side.
In the first, second, third, and fourth speeds, the solenoid valve 400 is energized and no oil pressure is generated in the oil passage 111, so the spools 232 and 233 are operated by the action of the spring 231. Oil passage 110 and oil passage 11 are set on the left side of the illustration.
8 and oil passage 135, and oil passage 135 and oil passage 136, respectively.
is de-energized, and hydraulic pressure is generated in the oil passage 111, causing the spool 2
32 and 233 are hydraulic pressure supplied to the left end oil chamber via the oil passage 111, and are set to the right in the figure, and communicate the oil passage 107 and the oil passage 118. The third shift valve 240 has a spring 24 on one side.
The spool 242 has the first, third,
In 5th gear, the solenoid valve 410 is energized and the oil passage 11
2, the spool 242 is set to the left in the figure by the action of the spring 241, communicating the oil passage 104 and the oil passage 117, and in the 2nd, 4th, and 6th speeds, the solenoid valve 410 is de-energized and the oil is not energized. Road 112
Hydraulic pressure is generated, and the spool 242 is set to the right in the figure with pressure oil supplied to the left end oil chamber via the oil path 112, and connects the oil path 104 and the oil path 119, and the oil path 117 and the discharge port 244. The throttle valve 200 includes an indicator valve 202,
A spring 204 is provided between the valve spool 203 and these valves, and the indicator valve strokes according to the amount of depression of the accelerator pedal, compressing the spring 204 and applying throttle pressure to the oil passage 12.
4. The cutback valve 201 guides the throttle pressure of the oil passage 124 to the oil passage 125 when oil pressure is supplied to the oil passage 113 (3rd, 4th, 5th, and 6th speed states).
Reduces throttle pressure and prevents unnecessary pump losses. The modulator valve 250 is composed of a spool 251 and a spring 252, and in the L position, regulates the pressure of the pressure oil guided through the oil passage 109 to generate modulator pressure in the oil passage 130. The lock-up control valve 290 includes a spool 292 with a spring 291 on one side, a first
In 2nd gear, no oil pressure is generated in the oil passage 293, so the spool 292 is set downward in the figure by the action of the spring 291, connecting the oil passage 120 and the oil passage 121, and in 3rd, 4th, 5th, and 6th gears, oil pressure is When the solenoid valve 420 in which oil pressure is generated in the chamber 293 is de-energized, line pressure is generated in the oil chamber 294 and the spool 292 is
The hydraulic pressure generated in the oil chamber 294 and the action of the spring 291 overcome the hydraulic pressure generated in the oil chamber 293, and when the solenoid valve 420 is energized, the pressure oil in the oil chamber 294 is discharged and the spool 292 is moved upward in the figure. The oil passage 120 and the oil passage 122 are connected to each other. D position...At the D position, the oil passage 104 is the oil passage 1.
06 and oil passage 107. In the first gear, the solenoid valve 430 is not energized, the solenoid valve 400 and the solenoid valve 410 are energized, and the spool 2 of the first shift valve 220 is energized.
22, the spool 23 of the second shift valve 230 is moved to the left position in the figure by the hydraulic pressure acting on the oil chamber 223.
2 and 233, the spool 2 of the third shift valve 240 is moved to the left position in the figure by the action of the spring 231.
42 are set to the left position in the figure by the action of the spring 241. The hydraulic pressure in the oil passage 107 is guided to the hydraulic servo 24A, and the oil pressure in the oil passage 104 is guided to the hydraulic servo 12A via the third shift valve 240 and the oil passage 117, and the clutch 24 and the clutch 12 are respectively engaged. . In the second gear, the solenoid valve 410 is de-energized, so the spool 2 of the third shift valve 240
42 moves to the right in the figure. The oil passage 117 is connected to the oil drain port 244 to discharge the pressure oil in the hydraulic servo 12A, and the pressure oil in the oil passage 104 is transferred to the hydraulic servo 1 via the third shift valve 240 and the oil passage 119.
9A, the clutch 12 is released and the brake 19 is engaged. In the third speed, the solenoid valve 430 and the solenoid valve 410 are energized, so the spool 222 of the 2-3 shift valve 220 moves to the right in the drawing, and the spool 242 of the third shift valve moves to the left in the drawing. The pressure oil in the oil passage 106 is transferred to the first shift valve 22.
0, the pressure oil in the oil path 104 is guided to the hydraulic servo 40A via the oil path 113, and the pressure oil in the oil path 104 is guided to the third shift valve 240
It is guided to the hydraulic servo 12A via the oil path 117,
The brake 40 and the clutch 12A are respectively engaged, and the pressure oil of the hydraulic servo 19A is supplied to the oil path 1.
19, the brake 19 is released because it is discharged through the third shift valve 240. In this way, during 2-3 gear shifting, the one-way clutch 13 is engaged when the brake 40 of the planetary gear transmission mechanism, which is the main gear transmission mechanism, is engaged, and the brake 19 of the overdrive mechanism, which is the auxiliary gear transmission mechanism, is released. After the engagement of the clutch 12, a smooth simultaneous gear change is performed by engaging the clutch 12. In the fourth speed, the solenoid valve 410 is de-energized and the spool 242 of the third shift valve 240 moves to the right in the figure. Oil passage 117 is oil drain port 244
The pressure oil in the hydraulic servo 12A is discharged, and the pressure oil in the oil passage 104 is guided to the hydraulic servo 19A via the third shift valve 240 and the oil passage 119, and the clutch 12 is released. Brake 19 is engaged. In the fifth gear, the solenoid valve 400 is de-energized, and the spool 232 of the second shift valve 230,
233 moves to the right in the figure. Pressure oil in oil passage 107 is guided to hydraulic servo 25B via second shift valve 230 and oil passage 118, and clutch 25 is engaged. In this manner, during 4-5 gear shifting, the one-way clutch 13 is engaged when the clutch 25 of the planetary gear transmission mechanism, which is the main gear transmission mechanism, is engaged, and the brake 19 of the overdrive mechanism, which is the auxiliary gear transmission mechanism, is released. After the engagement of the clutch 12, a smooth simultaneous gear change is performed by engaging the clutch 12. In the sixth speed, the solenoid valve 410 is de-energized and the spool 242 of the third shift valve 240 moves to the right in the figure. The oil passage 117 is connected to the oil drain port 244, and the pressure oil in the hydraulic servo 12A is discharged, and the pressure oil in the oil passage 104 is transferred to the third shift valve 2.
40, is led to the hydraulic servo 19A via an oil passage 119, and the brake 19 is engaged and the clutch 12 is released. I position...At the I position, the oil passage 104 is the oil passage 1.
06, 107, 108. The pressure oil guided to the oil passage 108 is transferred to the third shift valve 2
The spool 242 is guided to the oil chamber 243 of 40 and fixed to the left side in the figure. Therefore, solenoid valve 410
Even when the third shift valve 240 is in the second, fourth, and sixth speed states in which power is not supplied, the third shift valve 240 is not switched, and shifting to the second, fourth, and sixth speeds is prevented. Since the first shift valve 220 and the second shift valve 230 are switched in the same manner as in the D position, automatic gear shifting of three forward speeds, that is, the first, third, and fifth speeds, is performed in the I position. L position: In the L position, which is switched to apply engine braking, the oil passage 104 is connected to oil passages 106, 107, 108, and 109. Pressure oil guided to the oil passages 106, 107, and 108 is guided to each hydraulic servo in the same manner as in the I position.
The pressure oil guided to the oil passage 109 is connected to the modulator valve 25.
0 to generate a modulator pressure in the oil passage 130. In the fifth speed state, the oil passage 130 is in the second
The second shift valve 230 is closed by the spool 233 of the shift valve 230, but in the first and third gear states, the second shift valve 230 is closed.
It is connected to the oil passage 131 via 30. In the first speed state, the spool 2 of the first shift valve
22 is located on the left side in the figure, and is connected to an oil passage 131 and an oil passage 132.
are in contact with each other, and the modulator pressure of oil passage 130 is changed to oil passage 1.
31, 132 to the hydraulic servo 27B. At this time, since the relief valve 390 is provided in the oil passage 132, the modulator pressure in the oil passage 132 is set to a value equal to or lower than the set value of the relief valve 390. When the pressure in the oil passage 132 exceeds a set value, the relief valve 390 opens the oil passage 110 and the manual valve 210.
The pressure in the oil passage 132 is maintained at the set value by discharging the oil through the oil passage 132. When hydraulic pressure is introduced to the hydraulic servo 27B, the brake 27 is engaged and a first speed state where engine braking is effective is obtained. In the third speed state, the spool 222 of the first shift valve 220 is located on the right side in the figure and connects the oil passage 131 and the oil passage 133, so that the modulator pressure of the oil passage 130 is changed to the hydraulic pressure via the oil passages 131 and 133. Servo 26A
to engage the brake 26. When the brake is applied, a third speed state where engine braking is effective is obtained. In the fifth speed state, the spools 232 and 233 of the second shift valve 230 are located on the right side in the figure, and the oil passage 13
0 is closed by the spool 233, so D
The state is similar to that of the fifth speed at the I position and the I position. As described above, in the L position, automatic gear shifting is performed in three forward gears, 1st, 3rd, and 5th gears, in which engine braking is effective. During the 2-3 shift up at the D position and the 1-3 shift up at the I or L position, the spool 22 of the first shift valve 220
2 moves to the right in the figure, and the oil passage 106 becomes the oil passage 113.
The oil pressure in the oil passage 106 is suddenly generated in the oil chamber 293 of the lock-up control valve 290 via the oil passage 113, but at this time, the solenoid valve 420 is de-energized and line pressure is generated in the oil chamber 294. By keeping the spool 292 in place, the spool 292 is fixed at the lower position shown in the figure. At this time, the pressure oil in the oil passage 120 is guided to the oil passage 121, and the direct coupling clutch 50 in the torque converter is released. When the solenoid valve 420 is energized, the pressure oil in the oil chamber 294 is discharged, the spool 292 is set to the upper position shown in the figure by the oil pressure in the oil chamber 293, and the oil pressure in the oil passage 120 is guided to the oil passage 122. The direct coupling clutch is engaged. Further, a flow control valve 502 with a check valve is provided in the oil passage 122, and when pressure oil is supplied to the direct coupling clutch 50 through the oil passage 122, the flow control valve 502 with a check valve acts to Pressure oil is supplied slowly. R position: In the R position, the oil passage 104 is connected to the oil passage 110. The pressure oil in the oil passage 110 acts on the oil chamber 102A of the pressure regulating valve 102 to increase the line pressure, and is guided to the hydraulic servos 27A and 27B of the brake 27 via the orifice 134 to engage the brake 27. At this time, since pressure oil is led to the discharge side of the relief valve 390 via the oil passage 110, the relief valve 390 is not operated and line pressure is led to the hydraulic servos 27A and 27B. The hydraulic servo of the brake 27 consists of two sets of hydraulic servos 27A and 27B. During first speed engine braking, hydraulic pressure is supplied to one hydraulic servo 27B, and in the R position where the torque capacity is large, hydraulic pressure is supplied to both hydraulic servos 27A and 27B. configured to be supplied. In this case, the oil pressure is supplied to the hydraulic servo 27B by the orifice 134 more quickly than the oil pressure is supplied to the hydraulic servo 27A. The pressure oil in the oil passage 110 is the first
The spool 222 is guided to the oil chamber 224 of the shift valve 220 and fixed together with the spring 221 at the right position in the figure. For this purpose, the pressure oil in the oil passage 110 is supplied to the hydraulic servo 27B via the first shift valve 220 and the oil passage 132. However, as mentioned earlier, the hydraulic servo 27B is connected to the check valve 3 from the oil passage 110.
80, pressure oil is also supplied through the oil passage 132. Further, the pressure oil in the oil passage 110 is transferred to the second shift valve 2.
30 and through the oil passage 118 to the hydraulic servo 25B.
The oil is supplied to the hydraulic servo 25A through oil passages 118, 135, and 136, and the clutch 25 is engaged. The hydraulic servo of the clutch 25 consists of two sets of hydraulic servos 25A and 25B, and in the fifth forward speed, hydraulic pressure is supplied to one hydraulic servo 25B.
At the R position where the torque capacity is large, hydraulic pressure is supplied to both hydraulic servos 25A and 25B. In a low speed state, the solenoid valve 410 is energized, the spool 242 of the third shift valve 240 is located on the left side in the figure, and is connected to the oil passage 104 and the oil passage 117, so that the oil pressure in the oil passage 104 is transmitted through the oil passage 117. The clutch 12 is engaged by the hydraulic servo 12A. In high speed conditions, the solenoid valve 410 is de-energized and the spool 24 of the third shift valve 240
2 is located on the right side in the figure, and the oil passage 104 and the oil passage 119 are connected, and the oil pressure in the oil passage 104 is guided to the hydraulic servo 19A via the oil passage 119, and the pressure oil in the hydraulic servo 12A is transferred to the oil passage 117 and the third oil passage. shift valve 24
0 and is discharged from the discharge port 244, and the clutch 1
2 is released and the brake 19 is engaged. According to the present invention, the auxiliary transmission mechanism is a hydraulic control device for an automatic transmission, in which switching of the pressure oil supplied to each frictional engagement element of the main transmission is controlled by the first and second solenoid valves. Switching of the pressure oil supplied to the direct coupling friction engagement element or the non-direct coupling friction engagement element of the auxiliary transmission is performed by the first and second shift valves controlled by the third solenoid valve. By using the shift valve, six forward gears can be obtained by combining the gears of the main transmission and the gears of the auxiliary transmission. Furthermore, the six forward gears allow the most fuel-efficient gear to be selected depending on the driving conditions of the vehicle, which helps improve fuel efficiency, compared to the conventional four forward gears or three forward gears.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing a power transmission mechanism of an automatic transmission to which the present invention is applied, and FIG. 2 is a hydraulic circuit diagram showing an example of a hydraulic control device for an automatic transmission according to the present invention. In the figure, 1... Torque converter, 2... Overdrive mechanism, 3... Three forward speed planetary gear transmission mechanism,
DESCRIPTION OF SYMBOLS 100... Oil reservoir, 101... Oil pump, 102... Pressure regulating valve, 103... Second pressure regulating valve, 200... Throttle valve, 201... Cutback valve, 210...
Manual valve, 220...first shift valve, 230
...Second shift valve, 240...Third shift valve, 2
21,231,241...Spring, 222,2
32,233,242...Spool, 250...Coast modulator valve, 260,270,280...
Accumulator, 290... Lockup control valve, 300... Bypass valve, 310, 320, 33
0,340,350,360,370,502...
Flow control valve with check valve, 380...Check valve, 39
0...Relief valve, 400, 410, 420, 43
0... Solenoid valve, 12A, 19A, 24A, 2
5A, 25B, 26A, 27A, 27B, 40A
...Hydraulic servo.

Claims (1)

[Scope of Claims] 1. A hydraulic torque converter, a clutch connected to the output shaft of the hydraulic torque converter, a row of planetary gears, a clutch connecting two elements of the planetary gear, and one element of the planetary gear. a front-mounted auxiliary gear transmission mechanism having a friction engagement element consisting of a brake for fixing the auxiliary gear transmission mechanism and achieving two forward gear shifts; and a plurality of friction engagement elements connected to the output shaft of the auxiliary gear transmission mechanism. and an automatic transmission equipped with a main gear transmission mechanism that has two rows of planetary gears and achieves three forward speeds, comprising: a hydraulic source; a line pressure regulating valve that regulates the hydraulic pressure from the hydraulic source to line pressure; , a speed selection valve that manually switches the speed range, and first and second shift valves that switch the line pressure supplied to each frictional engagement element of the main gear transmission mechanism to achieve three forward speeds;
a third shift valve that switches the line pressure supplied to each frictional engagement element of the auxiliary gear transmission mechanism to achieve two forward speeds; and a first shift valve that controls the first, second, and third shift valves, respectively. , second and third solenoid valves, and a multi-stage speed change is obtained by a combination of each speed change of the main gear transmission mechanism and each speed change of the auxiliary gear transmission mechanism. Control device. 2 The auxiliary gear transmission mechanism includes a carrier connected to the output shaft of the hydraulic torque converter, a pinion rotatably supported by the carrier, a sun gear that meshes with the pinion, and a sun gear that meshes with the pinion and the auxiliary gear. a ring gear connected to an output shaft of a gear transmission mechanism; a clutch that removably connects the sun gear and the carrier; a brake that selectively fixes the sun gear; and a brake disposed between the sun gear and the carrier. 2. The hydraulic control device for an automatic transmission according to claim 1, wherein the overdrive device comprises a one-way clutch and a one-way clutch. 3. Simultaneous gear shifting of the main gear transmission mechanism and the auxiliary gear transmission mechanism includes a gear shift by engaging the one-way clutch after the one-way clutch is engaged with the release of the brake of the auxiliary gear transmission mechanism; 3. The hydraulic control device for an automatic transmission according to claim 2, wherein the hydraulic control device for an automatic transmission has a gear shift by engagement of a brake of a frictional engagement element of a gear transmission mechanism. 4. A patent claim characterized in that the third shift valve is configured to selectively supply line pressure to the clutch and brake of the auxiliary gear transmission mechanism regardless of the operation of other shift valves. A hydraulic control device for an automatic transmission according to item 2. 5 The third shift valve includes a spool having a first land, a second land, and a third land, and a spool having a first land, a second land, and a third land;
a first oil chamber formed at a land end to which control hydraulic pressure for the third solenoid valve is supplied; a second oil chamber formed by the first land and the second land; and a second oil chamber formed by the first land and the second land. a third oil chamber formed by the land and the third land; a fourth oil chamber formed at the end of the third land; and a fourth oil chamber provided on the third land side and extending in the direction of the first land. The line pressure oil passage and the oil passage connected to the clutch and the brake are selectively communicated by the second and third oil chambers, and the fourth oil chamber 5. The hydraulic control device for an automatic transmission according to claim 4, wherein the spool is biased toward the first land when hydraulic pressure is supplied to the chamber.