JPH0242146B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a control device for an automatic transmission, and more particularly to a control device for an automatic transmission suitable for starting with a small driving force. In conventional automatic transmissions, the elements of the gear mechanism arranged between the input shaft and the output shaft are fixed to the case, connected to and disconnected from the input shaft or output shaft, or connected to and disconnected from each other. The gear has been achieved. Generally, when a vehicle starts on a slope such as on a snowy road, it is desirable to start in a high gear (second gear) because the output torque is excessive in a low gear (first gear), which causes wheel slipping. However, when a vehicle equipped with an automatic transmission as described above starts in a high gear (second gear), it is necessary to cover the torque ratio of torque converter stall, and slippage in the torque converter occurs when starting in a high gear, and when starting in a low gear. It is larger than when starting. That is, the torque ratio within the torque converter becomes large. Therefore, the engagement force of the friction engagement device involved in achieving a high speed gear needs to be larger than that for normal automatic gear shifting (for example, D range), but the problem arises that the normal capacity is insufficient. Therefore, an object of the present invention is to facilitate starting in second gear, and a feature of the present invention is to provide a case in which elements of a gear mechanism disposed between an input shaft and an output shaft of an automatic transmission are mounted in a case. a plurality of frictional engagement devices for achieving at least two or more gears by being fixed to the input shaft or the output shaft or to each other, a hydraulic power source, and pressure oil from the hydraulic power source. A regulator valve equipped with a pressure boosting chamber for adjusting the pressure to a predetermined pressure and increasing this predetermined pressure in response to signal pressure, a manual switch, and a range for selecting a low gear and a high speed depending on driving conditions. Pressure oil from the regulator valve is selectively supplied to the friction engagement device in response to automatic switching between gear and low gear and a range in which only the high gear is selected upon input from the manual switch. and a signal valve that supplies the signal pressure to the pressure increasing chamber of the regulator valve when a range is selected and a manual switch is input. Located in the device. In the above hydraulic circuit, since the pressure in the hydraulic boost chamber of the regulator valve is increased, the output of the regulator valve, that is, the line pressure is correspondingly increased, and the second
Since the pressure on the servo mechanism of the frictional engagement device that engages at high speed is also increased, a large engagement force can be obtained. The boost chamber of the regulator valve is usually provided for other gears (reverse R, etc.) or for increasing pressure in response to the throttle pressure. In that case, no structural changes are required to the regulator valve. An embodiment of the present invention will be described below with reference to the accompanying drawings. The automatic transmission for a vehicle shown in the upper center of the drawing includes a torque converter 120 and a planetary gear transmission mechanism 14.
0 and becomes the main character. The torque converter 120 has a conventional structure and includes a pump impeller 123 connected to the engine output shaft 102, a turbine runner 125 connected to the output shaft 131, and a one-way clutch 127.
Stator 12 supported by case 100 via
9, and is further provided with a lock-up mechanism 135 that directly connects the input/output shafts 102 and 131. The planetary gear transmission 140 includes an input shaft 141 that is integrated with the torque converter output shaft 131, and the input shaft 1.
A first planetary gear set 150, a second planetary gear set 160, a multi-disc clutch C1 operated by a hydraulic servo C-1, and a hydraulic servo C-2 are connected to the output shaft 142 arranged in series with the output shaft 142.
multi-disc clutch C2 operated by, band brake B1 operated by hydraulic servo B-1, multi-disc brake B operated by hydraulic servo B-2.
2 and a one-way clutch F1. The first planetary gear set 150 includes a ring gear 151 connected to the clutch C1 via the input shaft 141, a carrier 155 spline-fitted to the output shaft 142, and a clutch C2 and a band brake B1 connected to the input shaft 141. Sun gear 153 and planetary gear 15 connected via
It has 7. The second planetary gear set 160 is the output shaft 1
a ring gear 161 spline-fitted to 42;
Automatic transmission case 1 via brake B2 and one-way clutch F1 parallel to brake B2.
00, and the input shaft 14 via the clutch C2 and brake B1.
1 and a planetary gear 167. In this embodiment, the sun gear 153 of the first planetary gear set 150 and the sun gear 163 of the second planetary gear set 160 are provided on an integral sun gear shaft 159. The band brake B1 is engaged or released by a hydraulic servo B-1 fixed to the case 100. This hydraulic servo B-1 is a hydraulic cylinder 1
76, a piston 177 fitted into the cylinder 176, and a return spring 178, and the piston 177 converts the inner space of the cylinder into an engagement oil chamber b1 for engaging the brake B1.
and a release oil chamber b2 for displacing the piston rearward and releasing the brake B1. Next, the hydraulic control device for the automatic transmission will be explained. 21 is an oil pump, 23 is a primary regulator valve, 27 is a secondary regulator valve, 2
9 is a throttle valve, 33 is an annual valve, 34 is a 1-2 shift valve, 36 is a 2-3 shift valve, and 38 is a low coast modulator valve.
modulate valve), 40 constitutes the signal valve.
2nd range boost valve
valve), 42 is an orifice control valve, 44
is a lock-up relay valve.
46 is a B-1 accumulator, 48 is a C-1 accumulator, 50 is a cooler bypass valve, 51, 52, 53, 54 is a flow control mechanism consisting of a check valve and an orifice in parallel, S1 is the 1-2 shift valve control solenoid valve, S2 is the 2-
3, a solenoid valve for controlling the shift valve, S3 a solenoid valve for controlling the lock-up relay valve, and 60 an electronic control device for controlling the solenoid valves S1 to S3. Next, the configuration of each valve and the operation of this control device will be explained. The oil pump 21 sucks up oil from an oil reservoir (not shown) through the oil strainer 20 and discharges it into the oil path 1 . The primary regulator valve 23 includes a spool 24 having a spring 231 on one side (lower side in the drawing) and a regulator plunger 25 arranged in series with the spool 24. The regulator plunger 25 is connected to the oil passage 9A which communicates with the oil passage 9 and the oil passage 3B via the three-way check valve 55.
It has a large diameter land 253 that receives the throttle pressure of oil passage 9 (described later) or 2nd range boost pressure of oil passage 3B (described later), and a small diameter land 251 that receives line pressure (described later) from oil passage 5. and throttle pressure), the spool 24 is pushed upward in the drawing. The spool 24 receives the feedback of the output hydraulic pressure (line pressure) applied to the upper end land 241 from above through the orifice 232, and receives the spring load of the spring 231 and the pressing force from the regulator plunger 25 from the lower part of the drawing. The opening areas of the port 233 communicating with the oil passage 1, the out port 234 communicating with the oil passage 7, and the drain port 235 are adjusted to adjust the oil pressure of the oil passage 1 to the oil pump discharge pressure and the above-mentioned oil pressure. The pressure is regulated according to the input oil pressure, and the oil pressure in oil passage 1 is adjusted to the line pressure, and the excess oil is supplied to oil passage 7, and the excess oil is supplied to oil passage 8.
The oil is discharged into the oil strainer 20. As a result, a line pressure is generated in the oil passage 1 that is regulated in accordance with vehicle running conditions such as vehicle speed and throttle opening.
The oil passage 1 and the oil passage 7 are connected through an orifice 236, and the minimum necessary amount of oil is supplied to the oil passage 7 regardless of the position of the spool 24. The secondary regulator valve 27 includes a spool 28 having a spring 271 disposed on one side (lower side in the drawing). The spool 28 is displaced by receiving the spring load of the spring 271 and the throttle pressure applied via the oil passage 9 from one side, and by receiving the hydraulic pressure of the oil passage 7 fed back to the upper end land 281 shown in the figure via the orifice 272 from the other side. and oil line 7
By adjusting the opening area of the port 273 communicating with the oil passage 11 and the opening of the drain port 275 communicating with the oil passage 11, secondary line pressure is generated in the oil passage 7, and excess oil is transferred from the oil passage 10 to the parts requiring lubrication as lubricating oil. The excess oil is then discharged from the oil passage 11 into the oil strainer 20. Note that the lubricating oil supply oil passage 10 is connected to the oil passage 7 via an orifice 276, and regardless of the position of the spool 28, the minimum necessary lubricating oil is supplied to the oil passage 10, thereby preventing seizure of parts requiring lubrication. is prevented. The throttle valve 29 includes a spool 30 having a spring 291 on its back on one side (upper side in the drawing), a throttle plunger 31 connected in series with the spool 30 via an intermediate spring 292, and a throttle plunger 31 that is connected in series with the spool 30 via an intermediate spring 292. The throttle cam 32 displaces the spool, and a locking plate 293 limits the amount of displacement of the spool. The throttle plunger 31 receives the feedback of the throttle pressure in the oil passage 9 and the pressing force from a cam 32 that is connected to the throttle pedal via a link mechanism (not shown) and rotates according to the amount of depression of the pedal. , and presses the spool 30 via the intermediate spring 292. The spool 30 receives the spring load of the spring 291 and the feedbag of the throttle pressure of the oil passage 9 from above, and is displaced by the pressing force of the intermediate spring 292 from the bottom of the drawing, and is connected to the import 294 and the drain connected to the oil passage 1. The opening area with the port 295 is adjusted to generate a throttle pressure in the oil passage 9 that increases in accordance with an increase in the throttle opening, which is one of the signals related to the output of the prime mover. Furthermore, when a signal oil pressure that increases in accordance with an increase in vehicle speed (or rotational speed of output shaft 142) is applied to the chamber at the upper end of the throttle valve 29 in FIG. 1 (the chamber in which the spring 291 is arranged), the throttle Throttle oil pressure can be generated that increases as the opening degree increases and decreases as the vehicle speed (or rotational speed of the output shaft 142) increases. The manual valve 33 includes a spool 331 that is manually operated by a shift lever (not shown) provided on the driver's seat, and has shift lever setting positions (setting ranges) P (park), R (reverse), and N (neutral). , D (drive), 2 (second), L (low)
According to Table 1, line pressure generation oil path 1
and communicates with oil passages 2 to 6. The oil passage 2 is connected to the hydraulic servo C-1 of the forward clutch C1 via a flow rate control valve 51 and an accumulator 46 provided downstream thereof, and also supplies control pressure to the lock-up relay valve 44. The oil passage 3 supplies line pressure to the 1-2 shift valve 34 and the 2nd range boost valve 40. The oil passage 4 is a 2-3 shift valve 36
The control pressure is supplied to the 2nd range boost valve 40 at the same time. The oil passage 5 supplies control pressure to the 2-3 shift valve 36, the low coast modulator valve 38, and the throttle valve. The oil passage 6 supplies line pressure to the 1-2 shift valve 34.

[Table] The driver selectively turns on the automatic gear shift switch and manual gear shift switch installed in the driver's seat to change the manual valve setting position, D, 2nd,
As shown in Table 2, for L, running is performed using automatic gear change or a specific gear position. The setting for traveling in automatic gear or a specific gear is determined by the electronic control unit 60, which inputs signals from the automatic gear shift switch and the manual gear switch, fixes the solenoid valves S1 and S2 to the respective automatic gear or specific gear. This is done by outputting as follows.

[Table] The 1-2 shift valve 34 includes a spool 35 with a spring 341 disposed on one side (lower side in the drawing). The spool 35 is connected to the spring 34 from one side.
1, and the upper end land 351 receives the spring load from the other side.
Then, it is displaced in response to the oil pressure P1 of the oil passage 1A, which communicates with the oil passage 1 via the orifice 342 and is equipped with an electromagnetic solenoid valve S1. When the solenoid valve S1 is energized, the valve port of the solenoid valve S1 is opened, the pressure in the oil passage 1A is exhausted, and the oil passage P is energized.
1 is at a low level, and the spool 35 is set to the upper position in the figure, which is the first speed side, by the action of the spring 341. As a result, the import 343 that connects to the oil passage 3 is closed, and the oil passage 6 and the second speed brake B1 are closed.
The engagement provided in the hydraulic servo B-1 communicates with the oil passage 3A that communicates with the hydraulic cylinder chamber b1, and the drain port 344 and the communication oil passage 6A that connects to the low coast modulator valve 38 communicate with each other. do. When the manual valve 33 is set to the D, N, R, and P ranges, the oil passage 6 is connected to the manual valve drain port 332 as shown in Table 1, so the oil passage 3A is filled with hydraulic pressure. Brake B does not occur.
1 is released. When the solenoid valve S1 is OFF (de-energized), the valve port of the solenoid valve S1 is closed, the oil pressure P1 of the oil passage 1A is at a high level equivalent to the line pressure, and the spool 35 is on the second speed side. Set downward. As a result, the oil passage 3 and the oil passage 3A communicating with the engagement side oil chamber b1 provided in the hydraulic servo B-1 of the second speed brake B1 are in communication, and the oil passage 6 and the low coast modulator valve are in communication with each other. 3
8 is connected to the connecting oil passage 6A. Further, line pressure is supplied to the oil chamber b1 of the hydraulic servo B-1 via the flow control valve 53 provided in the oil passage 3A and the accumulator 48 provided downstream thereof, and the brake B1 is engaged. The 2-3 shift valve 36 includes a spool 37 with a spring 361 disposed on one side (lower side in the drawing). The spool 37 is connected to the spring 3 from one side.
When the spring load of 61 and the line pressure are generated in the oil passage 5, the line pressure of the oil passage 5 is applied to the lower end land 372 shown in the figure, and the oil passage 4 is connected to the upper end land 371 shown from the other side via the orifice 360. , the oil pressure P of the oil passage 4A in which the electromagnetic solenoid valve S2 is provided.
2 and is displaced. Solenoid valve S2 is ON
When the spool 37 is energized (energized), the oil pressure P2 in the oil passage 4A is at a low level as in the case of the 1-2 shift valve, so the spool 37 is set upward in the figure (near the 2nd gear), and the oil passage 4 and the clutch are connected. Connecting oil road 4B to C2
Communication with is cut off. Solenoid valve S2
When OFF (de-energized), the spool 37 is set to the lower position in the figure (third speed side), the oil passage 4 and the oil passage 4B are connected, and the line pressure of the oil passage 4 is controlled via the flow rate control valve 54. Hydraulic servo C-2 of clutch C2
Line pressure is further supplied to the releasing side hydraulic cylinder b2 of the hydraulic servo B-1 of the brake B1 via the flow rate control valve 52. This engages clutch C2 and releases brake B1. Also, when line pressure is generated in the oil passage 5 (when the manual valve is set to the L position), the spool is moved upward (to the second speed side) in the lower end land 47 in the figure by the spring load of the line and spring 46. Fixed. The low coast modulator valve 38 has a spool 39 on one side of which a spring 381 is placed behind, receives the spring load of the spring 381 and the line pressure generated in the oil passage 5 from one side, and receives the spring load of the spring 381 and the line pressure generated in the oil passage 5 from the other side. The land 382 is displaced in response to the feedback of the output hydraulic pressure. Import 383 connected to oil path 6A, hydraulic servo B- of brake B2
It has an out port 385 and a drain port 387 connected to the oil passage 6B that communicates with the oil passage 6A. The pressure of the line is regulated and output to the oil path 6B. The oil passage 6A and the oil passage 6B are communicated via the low coast modulator valve 38 and also via the check valve 380, so that the oil passage 6B is connected to the oil passage 6A.
The oil is quickly drained through this check valve 380. The 2nd range boost valve 40 has a spool 41 on one side of which a spring 401 is placed behind. The spool 41 receives the spring load of the spring 401 from one side, and is displaced by receiving the line pressure of the oil passage 4 from the other side to the land 411 at the right end in the figure. When the manual valve 33 is in a setting position other than the D range and line pressure is not supplied to the oil passage 4, the spool 41
is set to the right in the drawing by the action of a spring 401, and the oil passage 3 is communicated via a three-way check valve 55 with an oil passage 3B that communicates with an input oil passage 9A to the plunger 25 of the primary regulator valve. As a result, when the driver selects manual gear shifting, the manual valve 33 is set to 2nd gear, and when starting in 2nd gear, the line pressure output from the primary regulator valve is leveled up by inputting line pressure from the oil passage 9A. , the clutch C
The torque capacity of the hydraulic servos C-1 and B-1 of the brake B1 and brake B1 is increased to smoothly start the second speed. When the manual valve 33 is set to the D range, line pressure is supplied to the oil passage 4, the spool 41 is set to the right in the figure, and the oil passage 4 is
B is connected to the drain port 402 and drained. As a result, the primary regulator valve 23 receives no line pressure input from the oil passage 9A, so the line pressure is maintained at normal (no level increase), which eliminates unnecessary torque capacity during automatic gear shifting performed when the manual valve is in the D range. This prevents an increase in shock during automatic gear shifting. The orifice control valve 42 has a spool 43 on one side of which a spring 421 is placed behind. The spool 43 is connected to the spring 42 from one side.
1, the land 431 at the right end in the figure receives the throttle pressure of the oil passage 9 and is displaced from the other side, and the oil passage 4B passes through the oil passage 4B and the flow rate control valve 52.
It also communicates with the connecting oil passage 4C which has connected to the release side hydraulic servo b2 of the hydraulic servo of the brake B1. In other words, when the throttle pressure in the oil passage 9 is above the set value, the communication between the oil passage 4B and the oil passage 4C is cut off, and when the throttle pressure is below the set value, the communication between the oil passage 4B and the oil passage 4B is interrupted.
and oil passage 4C. In the above configuration, shift lever positions P, R,
N, D, 2, operation of solenoid valves S1, S2, S3, clutches C1, C2, F1, brake B
By combining the operations of 1 and B2, the gear ratio shown below can be obtained.

[Table] When the driver operates the shift lever (not shown) to move the manual select valve 33 to the "2" position and presses the second speed start switch 61, the electronic control unit 60 at least switches on the solenoid valve S1. Be in a de-energized state. At this time, line pressure P _L introduced through oil passage 1 and port e is introduced into oil passages 2 and 3 via ports f and g, respectively. Clutch C1 is connected to serve mechanism C via oil passage 2.
Since pressure is introduced to -1, it becomes engaged. On the other hand, the spool 35 of the 1-2 shift valve 34 moves to the right position by de-energizing (OFF) the solenoid valve S1, so the spool 35 passes through the oil passage 3, the port 343 of the 1-2 shift valve 34, and the oil passage 3A. Servo mechanism B-
Hydraulic pressure is introduced into the first oil chamber b1, and the brake B1 is engaged. Therefore, the clutch C1 and the brake B1 are engaged and the second speed is achieved. At this time, the 1-2 shift valve, which normally achieves the first speed in the D range, the normal "2" range, etc. by means such as a second speed start switch, is prevented from entering the first speed state. On the other hand, the hydraulic pressure in the oil passage 4 connected to the booster valve 40 is controlled by ports h and i of the manual select valve 33.
, the spool 41 of the booster valve 40 has moved to the lower position. Therefore, the pressure inside the oil passage 3 is reduced by the booster valve 40 and the oil passage 3.
B, valve 55, regulator valve 2 through oil passage 9A
It will be introduced into the boost chamber of 3. Therefore, the plunger 25 of the regulator valve 23 moves upward, so the amount of oil discharged from the port 233 decreases.
The line pressure P _L in the oil passage 1 rises, and the servo mechanism C
The hydraulic pressure introduced into -1 and B-1 is also increased. Therefore, the engagement forces of the clutch C1 and the brake B1 are increased, making it possible to start the vehicle in the second gear reliably, thereby dramatically increasing the safety of the vehicle on snowy roads and the like.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing one embodiment of a transmission control device according to the present invention, and FIG. 2 is a diagram showing another embodiment in which the connection of the regulator valve is changed. In the diagram, B1...Band brake, B-1...Hydraulic servo, 23...Primary regulator valve, 2
7... Secondary regulator valve, 42... Orifice control valve, 29... Throttle valve,
33...Manual valve, 34...1-2 shift valve, 36...2-3 shift valve, 40...Booster valve, 51, 52, 53, 54...Flow control mechanism,
46, 48...Accumulator, 44...Lock-up relay valve, S1, S2, S3...Electromagnetic solenoid valve.

Claims (1)

[Claims] 1. At least 2 elements of a gear mechanism arranged between an input shaft and an output shaft of an automatic transmission are fixed to a case, connected to and disconnected from the input shaft or output shaft, or mutually connected to each other. a plurality of frictional engagement devices for achieving three or more gears; a hydraulic source; and adjusting the pressure oil from the hydraulic source to a predetermined pressure and increasing the predetermined pressure in response to a signal pressure. A regulator valve equipped with a pressure boosting chamber for the purpose of operation, and a manual switch that automatically switches between high and low gears according to the range and driving conditions that select the low gear, and when input from the manual switch is input, only the high gear is selected. a manual valve that selectively supplies pressure oil from the regulator valve to the frictional engagement device in accordance with the range in which the regulator valve is selected; A control device for an automatic transmission, comprising: a signal valve that supplies the signal pressure to a pressure increasing chamber of a regulator valve. 2. The control device for an automatic transmission according to claim 1, wherein the signal valve is operated by selective supply of pressure oil by the manual valve.