JPH0213184B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention provides a control device for an automatic transmission for an automobile;
In particular, it relates to a control device for an automatic transmission with an overdrive mechanism. An automatic transmission comprising a torque converter and a multi-stage gear transmission having a plurality of gear stages, in which an overdrive planetary gear transmission is disposed between the torque converter and the multi-stage gear transmission. The machine is already known.
For example, Japanese Patent Application Laid-open No. 55-63052 discloses that the planetary carrier of an overdrive planetary gear transmission is coupled to the turbine of a torque converter, and the internal gear is coupled to an input member of a multi-gear transmission. A Natsuta automatic transmission is disclosed. In this automatic transmission, when the sun gear and planetary carrier are connected by a direct clutch, the planetary gear mechanism rotates as a unit, and the torque converter turbine is directly connected to the input member of the multi-gear transmission. When the sun gear is engaged with the case side by the overdrive brake, the turbine of the torque converter is coupled in overdrive to the input member of the multi-gear transmission via the planetary gear transmission. In this mechanism, in order to operate the overdrive, the above-mentioned direct clutch is released and the overdrive brake is engaged at the same time, and the reverse control is necessary for direct drive.For this purpose, a vehicle speed-sensitive type Separate hydraulic supply passages are provided from the overdrive shift valve to the direct clutch actuator and overdrive brake actuator, respectively. Therefore, since the overdrive shift valve must control the supply and shutoff of hydraulic pressure to two hydraulic supply passages, it is necessarily large and requires extra space for the hydraulic supply passages. Furthermore, in the automatic transmission disclosed in JP-A-55-63052, the torque converter has a lock-up clutch that connects the pump impeller side and the turbine runner side, and this lock-up clutch is also controlled by hydraulic pressure. It is becoming more and more common.
That is, the lock-up clutch is pushed toward engagement by hydraulic fluid pressure within the torque converter and is maintained in a released state when release hydraulic pressure is supplied to the clutch. Therefore, a lock-up control valve is provided to control the supply and discharge of releasing hydraulic pressure to the torque converter, and the lock-up control valve is provided to maintain the lock-up clutch in the released position except in the overdrive position. A separate control valve is also required to generate a signal pressure that restricts the movement of the hydraulic control system, which complicates the hydraulic control system. An object of the present invention is to prevent an overdrive shift valve from increasing in size and to minimize the space for a hydraulic passage in an automatic transmission equipped with an overdrive planetary gear transmission. Another object of the present invention is to simplify the valve mechanism and hydraulic piping for lock-up operation control in an overdrive automatic transmission having a torque converter with a lock-up clutch. Still another object of the present invention is to provide a control device with a simple structure that allows overdrive to be manually released. That is, the control device for an automatic transmission with an overdrive mechanism of the present invention includes a hydraulically operated clutch that mutually engages any two of the sun gear, internal gear, and planetary carrier of the overdrive planetary gear transmission. The hydraulic pressure supply passage for engagement of the sun gear and the hydraulic pressure supply passage for release of the hydraulically operated brake that engages the sun gear toward the case side have a common passage on the downstream side of the overdrive shift valve. . According to this feature of the invention, at the position of the overdrive shift valve, the hydraulic passage for clutch engagement and the hydraulic passage for brake release are integrated, so that
There is no need to increase the size of the shift valve, the number of ports can be reduced, and the space for hydraulic passages leading to the clutch and brake can be reduced. Furthermore, in the present invention, in addition to the features described above, the torque converter has a lockup clutch connecting the pump impeller and the turbine runner, and a lockup control valve for controlling the hydraulic pressure supply to the lockup clutch. The lock-up control valve is restrained in the lock-up clutch release position by applying the aforementioned common passage hydraulic pressure. Therefore, when hydraulic pressure is present in the common passage and the clutch is engaged and the brake is released, that is, in a state other than the overdrive position, the lock-up control valve is restrained in the lock-up clutch release position, and the lock-up control valve is in the lock-up state. will not occur. In a torque converter in which the lock-up clutch is pushed in the engagement direction by the hydraulic pressure of the torque converter, and the releasing hydraulic pressure is applied to the clutch, the lock-up clutch is Release hydraulic pressure is constantly applied to the clutch, and the torque converter is prevented from locking up at gears other than overdrive. In the present invention,
Since the hydraulic pressure for restraining the lock-up control valve in this way is obtained from the common passage, the space for forming the passage can be reduced, and a separate control valve is required to form the hydraulic pressure for restraining the lock-up control valve. There is no need to provide one. According to a further feature of the invention, a manually controllable switching valve is provided for introducing hydraulic pressure into the common passage to engage the clutch and release the brake. Therefore, with this configuration, overdrive can be canceled at will. Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic diagram showing an example of an automatic transmission with an overdrive mechanism equipped with a control device of the present invention. The overdrive planetary gear transmission 50 is arranged between the transmission 20 and the overdrive planetary gear transmission 50. The torque converter 10 includes a pump impeller 11 coupled to the engine output shaft 1 via a converter cover 11a, a turbine runner 12 disposed opposite to the pump impeller 11, and a space between the pump impeller 11 and the turbine runner 12. The turbine 12 has a stator 13 disposed in the turbine 12, and an input shaft 14 is coupled to the turbine 12. A lock-up clutch 15 is provided between the input shaft 14 and the pump 11. This lock-up clutch 15 is constantly pushed in the engagement direction (to the left in FIG. 1) by hydraulic oil pressure circulating within the torque converter 10, and is formed between the lock-up clutch 15 and the converter cover 11a. When the lock-up oil chamber 60 is supplied with the lock-up oil from the outside, the lock-up piston is moved to the right in FIG.
It is held in the locked-up released state. The multi-stage gear transmission 20 includes a first planetary gear mechanism 21
The sun gear 23 of the first planetary gear mechanism 21 and the sun gear 24 of the second planetary gear mechanism 22 are connected by a connecting shaft 25. The input shaft 26 of the multi-gear transmission 20 is connected to the connecting shaft 25 via high, AND, and reverse clutches 27.
Furthermore, they can be connected to an internal gear 29 of the first planetary gear mechanism 21 via a forward clutch 28. An intermediate brake 30 is provided between the connecting shaft 25, that is, the sun gears 23, 24, and the transmission case. The planetary carrier 31 of the first planetary gear mechanism 21 and the internal gear 33 of the second planetary gear mechanism 22 are connected to the output shaft 34, and the planetary carrier 35 of the second planetary gear mechanism 22 and the transmission case are connected to each other. A low, AND, and reverse brake 36 and a one-way clutch 36a are provided between them. In the overdrive planetary gear transmission 50, a planetary carrier 52 that rotatably supports a planetary gear 51 is connected to the input shaft 14 of the torque converter 10, and a sun gear 53 is connected to an internal gear 55 via a direct clutch 54. It is now possible to combine. An overdrive brake 56 is provided between the sun gear 53 and the transmission case, and an internal gear 55
is connected to the input shaft 26 of the multi-gear transmission 20. The multi-stage gear transmission 20 is of a conventionally known type,
For example, it is of the same type as that disclosed in Japanese Patent Application Laid-Open No. 54-132062, and has three forward speeds and one reverse speed, and clutches 27, 28 and brake 3.
By appropriately operating the gears 0 and 31 as described later, a desired gear position can be obtained. The overdrive planetary gear transmission mechanism 50 connects the shafts 14 and 26 in a direct connection when the direct clutch 54 is engaged and the overdrive brake 56 is released, and when the brake 56 is engaged and the clutch 54 is released. When the shafts 14 and 26 are coupled in overdrive. FIG. 2 shows a hydraulic control circuit for operating each clutch and brake to obtain a required gear position. In this control circuit, oil is discharged into a pressure line 101 from an oil pump 100 driven by an engine output shaft. The pressure of the hydraulic oil is adjusted by the pressure regulating valve 102 and guided to the select valve 103. The select valve 103 is 1, 2, D, N, R,
P positions, and the select valve 103 has 1 and 2 positions.
and D position, pressure line 101 is connected to valve 1
It communicates with ports a, b, and c of 03. Port a is connected to an actuator 104 for actuating the forward clutch 28, which is held engaged when the valve 103 is in the position described above. Further, port a is connected to the first governor valve 106 via the second governor valve 105, and when the vehicle speed exceeds a set value, the line 10
7, a vehicle speed signal pressure is generated. The vehicle speed signal pressure on line 107 is applied to 1-2 shift valve 108, 2-3 shift valve 109, 2-3 timing valve 110, and pressure modifier valve 122 to operate these valves according to the vehicle speed. Port c is connected to a second lock valve 111, and the pressure in line 101 is applied to the valve 111 to maintain its spool in the upper position in the figure. The pressure at port b is controlled by the second lock valve 111.
is applied to the valve 111 so that pressure from port c is applied to the valve 111.
When the valve 111 is not acting, it acts to push the spool of the valve 111 downward. Port a is further connected to the 1-2 shift valve 108 via a line 112, and a line 113 from the shift valve 108.
When the spool of the second lock valve 111 is in the upper position, the intermediate brake 3
It is connected to a line 115 leading to the engagement side pressure chamber of actuator 114 of No. 0. Furthermore, port c
is connected to the 2-3 shift valve 109 via a line 116, and this line 116 is connected to a line 117 when the vehicle speed exceeds a set value and the 2-3 shift valve 109 is activated. Line 117 is actuator 1 of intermediate brake 30.
When hydraulic pressure is introduced into the pressure chamber, the actuator 114 operates the brake 30 in the release direction against the pressure in the engagement pressure chamber. Pressure in line 117 is also directed to actuator 118 of high, and reverse clutch 27, causing it to engage. The select valve 103 has a port d leading to the pressure line 101 in one position, and this port d
passes through line 119 to the 1-2 shift valve 108, and further passes through line 120 to the low, and,
It is connected to the actuator 121 of the reverse brake 36. Furthermore, the hydraulic control circuit is provided with a pressure modifier valve 122, a downshift valve 123, a throttle backup valve 124, and a vacuum throttle valve 125. Kaisho 54-132062
Since it is the same as that shown and explained in the publication, further explanation will be omitted, and the relationship between the gear position and the operation of the clutch and brake is shown in the table. In the table, when pressure is introduced to both the engagement side and the release side of the overdrive brake or intermediate brake, the brake operates on the release side.

【table】

[Table] In the embodiment of the present invention, the direct clutch 54 of the overdrive planetary gear transmission 50
A 3-4 shift valve 200 is further provided to control the overdrive brake 56 and the overdrive brake 56. This shift valve 200 has a spool 202 that is slidable in a valve hole 201, and a line 107 is connected to the valve hole 201 through a slit 241A provided in a sleeve-shaped guide 241 at one end of the spool 202. When the vehicle speed signal pressure is introduced and the vehicle speed exceeds a set value, the spool 202 is moved to the upper half position in the figure by the vehicle speed signal pressure. The pressure line 1 is connected to the valve hole 201.
A line pressure port 203 connected to 01 and an output port 204 are formed, and when the vehicle speed is lower than the set value and the spool 202 is in the lower half position in the figure, the line pressure port 203 is connected to the output port 204, When the vehicle speed exceeds the set value, spool 2
When 02 moves to the upper half position in the figure, both ports 2
03,204 is disconnected and the output port 204
is opened to drain port 240. The output port 204 of the 3-4 shift valve 200 is
Line 20 with orifice check valve 205
6 to the overdrive release valve 207. The valve 207 has a valve hole 208 and a valve hole 2.
08, and the spool 209 has a spring 21 provided at its right end.
0 is pushed to the left in the figure. Valve hole 2
08, pressure line 101 from pump 100
pressure port 211 leading to the 3-4 shift valve 2
Port 212 connected to line 206 from output port 204 of 00, and ports 211, 21
A port 213 between the two is formed. The pressure line 101 is connected to a chamber 215 at the left end of the valve hole 208 through a restriction 214, and the chamber 215 is connected to another restriction 216.
It is opened to drain after passing through. Therefore, in this state, the pressure acting on the chamber 215 is not large enough to move the spool to the right against the action of the spring 210 even if it acts on the left end of the spool 209 due to the pressure drop caused by the throttle 214. , aperture 21
6, line pressure is applied to chamber 215 and spool 209 is moved to the right. When the spool 209 is in the upper half position in the figure,
Port 212 is connected to port 213, and communication between ports 211 and 213 is cut off. Aperture 216
is closed, the pressure in chamber 215 increases, and when spool 209 moves to the lower half position in the figure, port 2
12 and 213 are cut off, and port 211 is connected to port 213. A solenoid 217 that is operated by a manual switch (not shown) is provided to open and close the diaphragm 216 as desired. The solenoid 217 holds the diaphragm 216 open when it is not energized, but when it is energized it opens the diaphragm 216.
It works to keep 6 closed. Direct clutch 54 has an actuator 218 for engaging it, and overdrive brake 56 has an actuator 219 for actuating it. Actuator 21
9 has an engagement-side pressure chamber 220 and a release-side pressure chamber 221, and when hydraulic pressure is introduced only into chamber 220, the brake 56 is engaged, and when hydraulic pressure is introduced into both chambers 220 and 221, the brake 56 is engaged. The brake 56 is released due to the pressure receiving area difference. The engagement side pressure chamber 220 of the actuator 219 is connected to the pressure line 101. Output port 213 of valve 207 is connected to common line 2
22, and this line 222 is connected to the actuator 2 of the clutch 54 through a one-way throttle 223.
18, and the release side pressure chamber 22 of the actuator 219 of the brake 56 via the one-way throttle 224.
Connected to 1. In addition, the common line 222
is also connected to a lockup control valve 225 for lockup clutch 15 of torque converter 10. That is, the valve 225 is connected to the valve hole 22
6 and a spool 227 that slides inside the valve hole 226, and the spool 227 is pushed leftward in the figure by a spring 228. Pressure from common line 222 is introduced into the right end of valve hole 226 and is configured to assist spring 228 . Vehicle speed signal pressure line 107 is connected to valve hole 226
The vehicle speed signal pressure is connected to the left end of the spool 227.
acts to push to the right. The valve hole 226 has a port 229 connected to the pressure line 101 and a lock-up release pressure line 2.
31 to the lockup oil chamber 60 of the torque converter 10;
0 is formed, and the spool 227 is connected to the spring 22.
When it is pushed by 8 and is in the upper half position in the figure,
Port 229 is connected to port 230 to direct hydraulic pressure to lockup oil chamber 60 to hold lockup clutch 15 in a released condition. When the vehicle speed reaches a set value or higher and no pressure is generated in the common line 222, the spool 227 is moved to the lower half position in the figure by the vehicle speed signal pressure, and the port 230 is closed off from the port 229. As a result, the lock-up oil chamber 6
The oil pressure within 0 becomes 0. The lock-up clutch 15 is therefore engaged by the hydraulic pressure within the torque converter 10. If oil pressure is generated in the common line 222, the spool 227 will not be pushed to the lower half position in the figure by the vehicle speed signal, and the lock-up clutch 15 will be held in the released state. To explain the operation of the control circuit described above, when the vehicle speed is lower than the set value and the vehicle speed signal pressure is low, the spool 202 of the 3-4 shift valve 200
is located in the lower half of the figure, and a port 203 communicating with the pressure line 101 is connected to an output port 204. If the throttle 216 is open, the pressure supplied to the port 215 will decrease, so the spool 209 of the override release valve 207 is in the upper half position in the figure, and the pressure in the port 204 is transferred from the line 206 to the ports 212, 213. via common line 222
guided by. Pressure in this common line 222 is directed to the actuator 218 of the direct clutch 54 to engage the clutch 54, and also causes the actuator 218 of the overdrive brake 56 to engage the actuator 218 of the direct clutch 54.
The brake 5 is guided to the release side pressure chamber 221 of the brake 5.
6 is released. Therefore, the overdrive planetary gear transmission 50 is in a directly connected state with a gear ratio of 1. At this time, the pressure of the common line 222 is introduced into the right end of the valve hole 226 of the lock-up control valve 225 and prevents the spool 227 from moving to the right, so that the lock-up clutch 15 of the torque converter 10 is engaged. can be prevented. That is,
When the transmission 50 is in the direct-coupled state, in other words, under gears other than overdrive, engagement of the lock-up clutch 15 is prevented. When the vehicle speed increases and reaches the set speed or higher, the spool 202 of the 3-4 shift valve 200 is moved to the upper half position in the figure by the vehicle speed signal pressure, so the output port 204 of the valve 200 becomes a line pressure port. 20
3 and connected to the drain port 240. Therefore, the pressure in the common line 222 decreases and the actuator 2 of the direct clutch 54
18 operates in the clutch releasing direction, and the pressure in the chamber 221 of the actuator 219 of the overdrive brake 56 decreases, causing the actuator 219 to operate in the brake engaging direction. In this way, the transmission 50 is placed in overdrive. As the pressure in the common line 222 decreases, when the vehicle speed further increases and reaches a higher set speed, the spool 227 of the valve 225 is moved to the lower half position in the figure by the vehicle speed signal pressure, and the port 230
is blocked from port 229 and drain port 24
2 and the lock-up oil chamber 60 is drained. This causes the lockup clutch 15
becomes engaged. In this state, when the solenoid 217 is energized by the operation of a switch (not shown), the aperture 216
is closed. Therefore, the pressure in chamber 215 increases and spool 209 of valve 207 is moved to the upper half position in the figure. In this position, the output port 213 of the valve 207 is connected to the pressure port 229, and the release hydraulic pressure is supplied to the lockup oil chamber 60 to release the lockup. At the same time, hydraulic pressure in common line 222 is directed to actuator 218 of direct clutch 54, causing it to engage.
The overdrive brake 56 is guided to the release side pressure chamber 221 of the actuator 219 of the overdrive brake 56, and the overdrive brake 56 is released and the transmission 50 is brought into direct connection. This configuration allows overdrive to be canceled at will.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of an automatic transmission showing an embodiment of the present invention, and FIG. 2 is a hydraulic circuit diagram for controlling the automatic transmission. 10... Torque converter, 15... Lock-up clutch, 20... Multi-stage gear transmission, 50...
...Planetary gear transmission for overdrive, 200...
...3-4 shift valve, 218... Direct clutch actuator, 219... Overdrive brake actuator, 222... Common line, 225... Lock-up control valve.

Claims (1)

[Scope of Claims] 1. A torque converter having a lock-up clutch, a multi-stage gear transmission having a plurality of gear stages, and a sun gear and an internal gear provided between the torque converter and the multi-stage gear transmission. A planetary gear transmission includes a planetary gear and a planetary carrier rotatably supporting the planetary gear, and any two of the sun gear, internal gear, and planetary carrier are engaged with each other to a hydraulically actuated direct clutch that directly connects the torque converter and the multi-gear transmission; an overdrive brake that engages the sun gear to the case side to overdrive connect the torque converter to the multi-gear transmission; and the torque converter. A control device for an automatic transmission with an overdrive mechanism, which is provided with a lockup control valve that controls hydraulic pressure supply to a lockup clutch of a converter, a hydraulic pressure supply passage for engaging the direct clutch, and the overdrive brake. A hydraulic pressure supply passage for releasing the lock-up clutch has a common passage downstream of the overdrive shift valve, and the hydraulic pressure in the common passage is also applied to the lock-up control valve to move the lock-up control valve to the lock-up clutch release position. A control mechanism for an automatic transmission with an overdrive mechanism, characterized in that the automatic transmission is restrained by the overdrive mechanism. 2. A torque converter, a multi-stage gear transmission having a plurality of gears, and a sun gear, an internal gear, a planetary gear, and a planetary gear that rotatably supports the planetary gear, and is provided between the torque converter and the multi-stage gear transmission. a direct clutch that engages any two of the sun gear, an internal gear, and the planetary carrier; and a direct clutch that engages the sun gear with a case side. In a control device for an automatic transmission with an overdrive mechanism, the overdrive brake is provided with an overdrive brake, and the overdrive brake is released when the direct clutch is engaged. The passage and the hydraulic pressure supply passage for releasing the overdrive brake have a common passage on the downstream side of the vehicle speed sensitive control valve for overdrive shifting, and hydraulic pressure is introduced into the common passage to release the direct clutch. A control device for an automatic transmission with an overdrive mechanism, comprising a manually controllable switching valve for engaging the overdrive brake and releasing the overdrive brake.