JPH0751984B2 - Shift control system for automatic transmissions for vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to an improvement in a control device for an automatic transmission for a vehicle.

[Conventional technology]

A conventional automatic transmission for a vehicle is disclosed in, for example, US Pat. No. 2,995,957.
As described in Japanese Patent Laid-Open Publication No. 2005-242242, an engagement element (hereinafter, referred to as an engagement side engagement element) on an engaged side at the time of shifting from a relatively low speed shift stage to a relatively high speed shift stage The engagement force is controlled so that the rate of change (deceleration) of the engine rotation speed becomes the target rate of change, and the shift shock during the shift is reduced.

[Problems to be solved by the invention]

However, in the above-described configuration, the engagement side engagement element to which torque is transmitted after the gear shift is changed from the engagement side engagement element to which the torque is transmitted before the gear shift is started (hereinafter referred to as a disengagement side engagement element). It was difficult to achieve a smooth switching of the torque transmission path to the coupling element. In other words, if the disengagement side engagement element is not fully engaged yet and the disengagement side engagement element is released, the shift time becomes long and damage to both engagement elements is accelerated, and vice versa. If the release of the release side engagement element is delayed with respect to the engagement of the engagement side engagement element, both engagement elements will be in the engaged state at the same time, so an uncomfortable feeling of deceleration (shift shock) during shifting.
There was a problem with.

[Structure of Invention]

The present invention was devised in view of the above, and an input shaft to which a driving force is transmitted, first and second engaging elements that can be selectively engaged, and a driving force to the input shaft are transmitted. Drive state detection means for detecting that the first engagement element is generated in response to an output signal and a shift command signal from the drive state detection means. A shift control device that controls the engaging force of the first engagement element and the engagement force of the second engagement element so as to engage and release the second engagement element. Is a first engagement force control means for increasing the rotation speed of the input shaft by reducing the engagement force of the second engagement element in response to the shift command signal, and the rotation speed of the input shaft for the shift command. Target higher than the input shaft rotation speed before signal output by a specified value Second engagement force control means for controlling the engagement force of the second engagement element so as to match the rolling speed, and effective gear shift for detecting that the effective gear shift is started by the engagement of the first engagement element. After the engagement is started in response to the start command means and the shift command signal and the effective shift start is detected by the effective shift start detecting means, the engaging force of the first engagement element is controlled to a desired value. And a third engagement force control adjusting means that engages with each other, and a shift control device for an automatic transmission for a vehicle.

[Action]

According to the above configuration, the engagement force of the second engagement element is adjusted so that the rotation speed of the input shaft coincides with the target rotation speed that is a predetermined value higher than the rotation speed before the generation of the command signal in response to the generation of the command signal. It is configured to control the engagement force of the first engagement element to a desired value when the effective shift is started by the engagement start of the first engagement element. Second
It is possible to prevent the engaging elements from being brought into the completely engaged state at the same time, and to achieve the effect of smoothly switching the torque transmission path from the second engaging element to the first engaging element.

〔Example〕

 An embodiment of the present invention will be described in detail with reference to the drawings.

In FIG. 1, a drive shaft 10 directly connected to a crank shaft of an engine (not shown) is connected to a pump 16 of the torque converter 12 via an input casing 14 of the torque converter 12, and a stator 18 of the torque converter 12 is connected. Is connected to a speed change casing 22 via a one-way clutch 20. The turbine 24 of the torque converter 12 is connected to the clutch 28, the clutch 30 and the clutch 32 via the input shaft 26, and the output side of the clutch 28 is connected to the first simple planetary gear via the first intermediate shaft 34. It is connected to a first carrier 38 of a device 36 (hereinafter, simply referred to as a first gear device 36) and a second carrier 42 of a second simple planetary gear device 40 (hereinafter, simply referred to as a second gear device 40) and The first intermediate shaft
The output side of the clutch 30 is connected to a brake 44 for stopping the rotation of the first gear 34 of the first gear device 36.
46, the output side of the clutch 32 is connected via the second intermediate shaft 48 to the first ring gear 50 of the first gear device 36 and the second sun gear 52 of the second gear device 40 and the second It is connected to a brake 54 for stopping the rotation of the intermediate shaft 48.

The first gear device 36 includes the first sun gear 46 and the sun gear 4
6, a first pinion gear 56 that meshes with the first pinion gear 56, the first pinion gear 56 that rotatably supports the same pinion gear 56, and the first carrier 38 that meshes with the first pinion gear 56 that is rotatable by itself.
The ring gear 50, and the second gear device 40.
Is a second sun gear 52, a second pinion gear 58 that meshes with the sun gear 52, a second pinion gear 58 that rotatably supports the pinion gear 58, and a second carrier 42 that is rotatable by itself and a second ring gear that meshes with the second pinion gear 58. It consists of 60. And, the second ring gear 60 is the same as the first ring gear 60.
Output gear via a hollow output shaft 62 through which the intermediate shaft 34 is inserted
It is connected to 64.

The output gear 64 meshes with a driven gear 68 provided at the right end of an intermediate transmission shaft 66, which is arranged substantially parallel to the input shaft 26, via an idler 70.
The left end of is connected to the final reduction gear 76, which is connected to the drive axle 74 via the differential gear unit 72.

As is apparent from FIG. 1, the transmission casing 22 is formed so as to include the torque converter 12 to the output gear 64, the intermediate transmission shaft 66, the differential gear device 72 and the like.

Each of the above-mentioned clutches and brakes is provided with an engagement piston device or a servo device, etc., which will be described later, and is engaged and released by supplying and discharging hydraulic pressure. And
The above hydraulic pressure is selectively supplied to and discharged from each clutch and brake by the hydraulic control device shown in FIG. 2, and a combination of operation of the clutch and brake achieves four forward gears and one reverse gear.

Reference numeral 76 is an input shaft rotation speed sensor for detecting the rotation speed of the input shaft 26, and 78 is a vehicle regulation sensor for detecting the rotation speed (corresponding to the vehicle speed) of the output gear 64.

Table 1 shows the relationship between the operation of each clutch and brake and the status of the gear stage. In the table, "○" indicates engagement of the clutch or brake, and "1" indicates their release. Shows.

In the above structure, when the brake 44 and the clutch 30 are engaged, the first carrier 38 and the second carrier 42 are fixed and become a reaction force element, and the driving force from the driving shaft 10 is the torque converter 12, the input shaft 26, and the clutch. 30, first sun gear 46, first pinion gear 56, first ring gear 50, second sun gear 52, second
It is transmitted to the output shaft 62 via the pinion gear 58 and the second ring gear 60, and further transmitted to the drive axle 74 via the output gear 64, the intermediate transmission shaft 66, and the final reduction gear 76, as is apparent from Table 1. First speed is achieved.

Next, while maintaining the engaged state of the clutch 30, brake
When 44 is released and the brake 54 is engaged, the rotation of the first ring gear 50 and the second sun gear 52 is stopped and becomes a reaction force element, and the driving force is the first sun gear 46, the first carrier 38, and the second carrier 38.
It is transmitted to the output gear 64 via the carrier 42, the second ring gear 60, and the output shaft 62, and the second speed is achieved.

Next, with the clutch 30 kept engaged, the brake 54
And the clutch 28 is engaged, the first sun gear 46 and the first carrier 38 rotate integrally, so that the first gear device
The whole 36 rotates integrally. Therefore, since the second sun gear 52 and the second carrier 42 rotate integrally, the entire second gear device 40 also rotates integrally, and the third speed at which the input shaft 26 and the output gear 64 have the same rotation speed is achieved. To be done.

Further, the clutch 28 is maintained while the engagement state of the clutch 28 is maintained.
When 30 is released and the brake 54 is engaged, the second sun gear 52
Is a reaction force element, the driving force is the first intermediate shaft, the second sun gear 52, the second pinion gear 58, the second carrier 42, the output shaft 62.
The fourth speed of the overdrive is achieved in which the rotation of the output gear 64 is transmitted through the output gear 64 through the gears and the rotation of the output gear 64 is faster than the rotation of the input shaft 26.

Next, when the clutch 28 and the brake 54 are disengaged and the clutch 32 and the brake 44 are engaged, the second carrier is released.
42 becomes a reaction force element, and the driving force is the second intermediate shaft, the second sun gear 52, the second pinion gear 58, the second ring gear 60, the output shaft 62.
Is transmitted to the output gear 64 via the gear and the reverse speed is achieved.

Next, in the gear transmission shown in FIG. 1, a hydraulic control device for achieving the gear stages shown in Table 1 and its operation will be described.

The hydraulic control device shown in FIG. 2 has a variable discharge type oil pump 8 from an oil sump 80 through an oil pump filter 82 and an oil passage 84.
The pressure oil discharged from 6 is supplied to the torque converter 12 and the clutches 28, 30, 3 of the transmission shown in FIG.
2 and the brakes 44 and 54 are selectively supplied to the clutches and brakes according to the operating condition of the vehicle. Mainly, the pressure regulating valve 88, the torque converter control valve 90, the pressure reducing valve
92, manual valve 94, first hydraulic control valve 96, second hydraulic control valve 98, third
Hydraulic control valve 100, fourth hydraulic control valve 102, first switching valve 104, second
Switching valve 106, third switching valve 108, fourth switching valve 110, fifth switching valve 11
2, sixth switching valve 114, and first solenoid valve 116, second solenoid valve 118, third solenoid valve 120, fourth solenoid valve 122
Is a constituent element, and each element is connected by an oil passage.

Each of the solenoid valves 116, 118, 120, 122 is a three-way valve which has the same structure and operates according to an electric signal from an electronic control unit 124, which will be described later, and has coils 126, 128, 130, 13 inside thereof.
2, valve bodies 134, 136, 138, 140, and springs 142, 144, 146, 148 for urging the valve bodies in one direction are provided, and the above-mentioned valve bodies 13 in the non-excited state of the coils 126, 128, 130, 132.
Oil passages 162,164,166,168 and oil passages 170,172,174,1 connecting 4,136,138,140 to the oil passage 160 by closing the orifices 152,154,156,158 disposed in the oil passage communicating with the discharge port 150.
The fluid passages 178, 180, 182, 184 in which the 76 are disposed are respectively communicated with each other, and each valve element has the above-mentioned fluid passages in the excited state of each coil.
Orihuis 186,188,19 installed in 162,164,166,168
It is configured such that the oil passages 178, 180, 182, 184 and the respective oil passages communicating with the discharge port 150 are communicated with each other by closing 0, 192.

The electronic control unit 124 outputs a continuous current to each solenoid valve 116, 118, 120, 122 according to the operating state of the vehicle to output oil passages 178, 1
The hydraulic pressure in 80, 182, 184 is duty-controlled, and the main input elements are the input shaft rotation speed sensor 76, vehicle speed sensor 78, valve opening sensor 194 for detecting the throttle valve opening of the engine (not shown), and lubricating oil temperature. An oil temperature sensor 196 for detecting a shift lever position, a select position sensor 198 for detecting a selection of shift lever position arranged in the vehicle interior, and a range of automatically shiftable gear positions between three forward gears and four forward gears. It is composed of a signal from the auxiliary switch 200 or the like for switching.

The pressure oil discharged from the oil pump 86 to the oil passage 202 is regulated to a predetermined pressure by the pressure regulating valve 88 and guided to the torque converter control valve 90, the pressure reducing valve 92 and the manual valve 94.

Manual valve 94 is a spool that can select 6 positions of L, 2, D, N, R, P
When the L, 2, and D positions are selected, the oil passage 202 is changed to the oil passage 206.
1st solenoid valve 116, 2nd solenoid valve 118, 3rd solenoid valve 120, 4th solenoid valve 122
According to the combination of ON and OFF, the first to fourth speed forward operating states are appropriately achieved by the gear transmission, and when the N position is selected, the oil passage 206 and the oil passage 208 communicating with the clutch 32 are connected. Oilway 202
Communication with the lands 210 and 212 of the spool 204 and the oil passages 206 and 208 are connected to the oil discharge ports formed at both ends to achieve a neutral state, and when the R position is selected, the oil passage 202 is oiled. The gear transmission is connected to the passage 208 to achieve the reverse speed change state (shift stage), and when the P position shown in the figure is selected, the land 210 of the spool 204 blocks the oil passage 202, so that the gear transmission is substantially realized. It is to be in a neutral state.

The pressure regulating valve 88 has a spool 220 having pressure receiving surfaces 214, 216, 218 and a spring 222. When the second speed, the third speed or the fourth speed is achieved, the hydraulic pressure from the oil passage 202 is applied to the pressure receiving surface 214. Acts via the oil passage 226 to regulate the oil pressure in the oil passage 202 to a predetermined value (hereinafter referred to as the first line pressure), and when the first speed gear stage is achieved, the pressure receiving surface. 214
The hydraulic pressure from the oil passage 202 acts on the pressure receiving surface 216 and the hydraulic pressure from the oil passage 224 acts on the pressure receiving surface 216 so that the hydraulic pressure in the oil passage 202 is higher than the first line pressure by a predetermined value (second line pressure and The oil passage communicating with the oil passages 202, 224, 208 on the pressure receiving surfaces 214, 216, 218 when the reverse speed is achieved.
The hydraulic pressure of 226 acts on each to regulate the hydraulic pressure of the oil passage 202 to a predetermined value (referred to as a third line pressure) higher than the second line pressure. The torque converter control valve 90 has a spool 228 and a spring 230, and the pressure regulating valve 88
The hydraulic pressure of the oil passage 202 regulated by is applied to the right end pressure receiving surface of the spool 228 via the oil passage 232, the oil passage 234, and the oil passage 236, and is adjusted to a predetermined pressure by the balance with the urging force of the spring 230. And supplies it to the torque converter 12 via the oil passage 234. The oil discharged from the torque converter 12 is supplied to each lubricating section of the transmission through the oil cooler 238.

The pressure reducing valve 92 has a spool 240 and a spring 242, and the hydraulic pressure from the oil passage 202 is adjusted by the balance between the hydraulic pressure due to the area difference between the pressure receiving surfaces 244 and 246 formed opposite to the spool 240 and the urging force of the spring 242. The pressure is adjusted to a predetermined adjusted hydraulic pressure that is lower than the first line pressure, and is supplied to the left pressure receiving portion of each of the hydraulic pressure control valves 96, 98, 100, 102 described below via the oil passage 160. The pressure is further adjusted according to the operating state of the solenoid valves 116, 118, 120, 122 and supplied to the right pressure receiving surface of each spool of the hydraulic control valve.

The first hydraulic control valve 96 has a spool 248 and a spring 250, and is increased / decreased according to the increase / decrease of the duty ratio of the first solenoid valve 116 and acts on the right pressure receiving surface 252 of the spool 248 via an oil passage 178. Control oil pressure to the left in the drawing, the resultant force of the urging force to the left in the drawing by the spring 250, the area difference between the pressure receiving surface 253 and the pressure receiving surface 255 of the land 254, and the pressure receiving surface 256.
The hydraulic pressure supplied from the oil passage 206 to the oil passage 260 can be controlled to a desired value according to the duty ratio by the balance with the resultant force of the hydraulic pressure to the right in the drawing due to the area difference between the pressure receiving surface 257 and the pressure receiving surface 257. Further, when the first solenoid valve 116 is continuously excited, that is, when the duty ratio is 100%, the control oil pressure acting on the pressure receiving surface 252 becomes 0, the spool 248 is displaced to the right in the drawing, and the land 254 is removed. Oil port with port 258 closed
Since 260 is communicated with the oil discharge port, oil pressure is not guided to the oil passage 260, and conversely, the duty ratio is 0% (continuously non-excitation).
In this case, the adjusting hydraulic pressure acts on the pressure receiving surface 252, the spool 248 is displaced leftward in the drawing, and the port 258 is opened, so that the hydraulic pressure of the oil passage 206 is guided to the oil passage 260 without being reduced.

2nd hydraulic control valve 98, 3rd hydraulic control valve 100, 4th hydraulic control valve 1
02 has exactly the same structure as the first hydraulic control valve 96, and has spools 262, 264, 266 and springs 268, 2 respectively.
70, 272, second solenoid valve 118, third solenoid valve
120, which can disconnect the communication between the oil passage 206 and the oil passages 274, 276, 278 according to ON / OFF of the fourth solenoid valve 122 and the duty ratio, and can control the contact and the oil pressure of the oil passages 274, 276, 278 to desired values. Is.

The switching valves 104 to 114 prevent reverse operation of the associated clutches and brakes to prevent the gear transmission from locking up, and when the electronic control unit 124 malfunctions, the manual valves 94 are switched to reverse the valves. , The neutral and forward third speeds are achieved so that the first switching valve 104 includes a spool 284 and a spool 284 having lands 280, 282 having the same pressure receiving area. It has a spring 286 that presses to the right in the drawing, and hydraulic chambers 283 and 285 formed at both ends of the spool 284.
In the right end hydraulic chamber 283, the engine is operating, that is, the oil pump 8
6 The line pressure is constantly guided through the oil passage 344 during operation, and the hydraulic pressure is guided to the left end hydraulic chamber 285 when the clutch 30 needs to be reliably released.
The resultant force to the right in the drawing due to the hydraulic pressure to the left end hydraulic chamber 285 and the biasing force of the spring 286 overcomes the hydraulic pressure to the left due to the line pressure guided to the left end pressure receiving chamber 283, and the spool 28
Since 4 is displaced to the right in the drawing, the communication between the oil passage 260 and the oil passage 288 is cut off by the land 280 and the oil passage 288
Is communicated with the exhaust port (EX) to securely release the clutch 30 and prevent its malfunction. Further, when the oil pressure is not guided to the left end hydraulic chamber, the oil pressure in the right end hydraulic chamber overcomes the biasing force of the spring 286 and displaces the spool 284 to the left end position.
The communication with 288 is established, and the clutch 30 can be engaged.

Of the other switching valves, the second, fifth, and sixth switching valves 106, 112, 114
Are spools 294, 332, 340 having the same land as the first switching valve and having two lands each having the same pressure receiving area, springs 296, 334, 342 for pressing the spools 294, 332, 340, and a hydraulic chamber 29 to which the line pressure is constantly guided.
3,331,339 and hydraulic chambers 295,33 for selectively supplying and discharging hydraulic pressure
When the hydraulic pressure is not supplied to the hydraulic chambers 295, 333, 341, the lands 292, 330, 336 are used to close the drain port and the oil passages 298 and 300, the oil passages 326 and 314, and the oil passages 278 and 3 are provided.
When the hydraulic pressures are supplied to the hydraulic chambers 295, 333, 341, the oil passages 298, 326, 278 are cut off by the lands 290, 328, 338, and the oil passages 300, 314, 358 are connected to the oil discharge port.

The third switching valve 108 has lands 302, 3 having the same pressure receiving area.
A spool 308 having 04 and 306 formed therein, a spring 310 for pressing the spool 308 to the right in the figure, a hydraulic chamber 307 to which a line pressure is always guided, and a hydraulic chamber 309 to which hydraulic pressure is selectively supplied are provided. When the hydraulic pressure is not supplied to the chamber 309, the oil discharge port (EX) is closed between the lands 302 and 304, and the oil passage 316 connected to the brake 54 is connected to the oil passage 312 connected to the fourth switching valve 110 described later. Then, when the hydraulic pressure is supplied to the hydraulic chamber 309, the oil passage 312 is connected to the oil discharge port (EX), the oil passage 316 is connected to the hydraulic chamber 285 of the second switching valve 104, and the fifth switching valve 112 is connected. It is configured to communicate with the connected oil passage 314.

The fourth switching valve 110 includes lands 318, 3 having the same pressure receiving area.
The spool 322 in which the 20 is formed, the spring 324, the hydraulic chamber 319 to which the line pressure is supplied, and the hydraulic chamber 321 to and from which hydraulic pressure is selectively supplied and discharged are substantially the same as the switching valves other than the third switching valve 108. When the oil pressure is not supplied to the oil pressure chamber 321, the oil passage 276, through which the oil pressure from the third oil pressure control valve 100 is guided, is connected to the sixth switching valve 1 via the ball valve 370 and the oil passage 372.
14 communicating with the oil passage 368 connected to the hydraulic chamber 341 and the oil passage 312. When hydraulic pressure is supplied to the hydraulic chamber 321, the land 320 closes the oil passages 312 and 368, and the oil passage 276 connects the fifth switching valve.
It is configured to communicate with the oil passage 326 connected to 112.

Note that the first to fourth solenoid valves 116, 118, 120, 122 are turned on.
Table 2 shows the relationship between the combination of (excitation) and OFF (non-excitation) and the gear position.

Next, the operation of the hydraulic control device will be described. When the driver of the vehicle sets a conventionally known selector lever (not shown) disposed in the passenger compartment of the vehicle to the P or N position, the manual valve 94 mechanically or electrically connected to the selector lever is set to P or N. When the N position is set and the engine is started, the oil pressure in the oil passage 202 generated by the oil pump 86 and controlled to a predetermined value by the pressure regulating valve 88 is the oil passage 232, the torque converter control valve 90, and the oil. To the torque converter 12 via the passage 234, to the oil passage 160 after being adjusted to the regulated hydraulic pressure by the pressure reducing valve 92, and further via the oil passage 344, the hydraulic chamber 319 and the sixth switching valve of the fourth switching valve 110. The hydraulic chamber 339 of 114, the hydraulic chamber 293 of the second switching valve 106, the hydraulic chamber 307 of the third switching valve 108, the hydraulic chamber 283 of the first switching valve 104, and the hydraulic chamber 331 of the fifth switching valve 112, respectively. . Therefore,
The spools 322, 340 of the fourth and sixth switching valves 110, 114 are displaced rightward in the drawing, and the other switching valves are displaced leftward in the drawing.

Here, when the driver operates the selector lever to select the D position, the manual valve 94 is set to the D position and the oil passage 20
The hydraulic pressure of 2 is guided to the oil passage 206 via the manual valve 94, and further,
The second solenoid valve 118 and the third solenoid valve 120 are excited from the electronic control unit 124, the fourth solenoid valve 122 is immediately demagnetized, and the first solenoid valve 116 is operated at a predetermined duty ratio, and then the duty ratio is gradually increased. A signal to reduce and finally degauss is output.

The excited valve bodies 136, 138 of the solenoid valves 118, 120 are displaced upward in the drawing to close the orifices 188, 190, so that the hydraulic pressure in the oil passages 180, 182 is discharged from the discharge port 150 via the orifices 172, 174 and the orifices 154, 156. Therefore, the spool of the second and third hydraulic control valves 98,100
The adjusting hydraulic pressure from the oil passage 160 acting on the pressure receiving surface on the left side of the lands 346, 348 formed on the 262, 264 overcomes the biasing force of the springs 268, 270 and displaces the spools 262, 264 to the right in the drawing, so that the oil passages 274 and 276. Is disconnected from the oil passage 206 and communicates with the discharge ports 269 and 271. Since the demagnetized valve body 140 of the fourth solenoid valve 122 closes the orifice 158, the adjusted hydraulic pressure from the oil passage 160 is not reduced and acts on the right pressure receiving surface of the spool 266 via the oil passage 184 to act on the spool 266. Is held at the left end position in the drawing, and the communication state between the oil passage 206 and the oil passage 278 is maintained via the oil passage 350, the ball valve 352, and the oil passage 354. The hydraulic pressure of the oil passage 278 is supplied to a hydraulic chamber (not shown) for actuating the brake 44 via the sixth switching valve 114 and the oil passage 358 to actuate the brake 44. Further, the oil pressure introduced to the oil passage 358 is transferred to the oil passage 360, the ball valve 362,
It is supplied to the hydraulic chamber 295 of the second switching valve 106 via the oil passage 364 to displace the spool 294 to the right in FIG. 2, the oil passage 298 is blocked by the land 290, and the oil passage 300 communicates with the oil discharge port. Therefore, the release of the clutch 28 is reliably held. And the above oil passage
The oil pressure in 358 further acts on the pressure receiving surface 216 of the pressure regulating valve 88 via the oil passage 224, and adjusts the oil pressure in the oil passage 202 to the second line pressure.

On the other hand, since the first solenoid valve 116 is first operated at a predetermined duty ratio, it is determined according to the duty ratio and the resultant force of the hydraulic pressure and the biasing force of the spring 250 acting on the right pressure receiving surface of the spool 248 and the spool 248. A hydraulic pressure of a magnitude corresponding to the position of the spool 248, which is balanced with the hydraulic pressure acting on each pressure receiving surface of the, is guided to the oil passage 260, and a part of the hydraulic pressure is applied to the first switching valve 1
04, it is guided to the clutch 30 through the oil passage 288, and the clutch 30 is engaged with the engaging force according to the magnitude of the hydraulic pressure, and the other part is hydraulic pressure of the fifth switching valve 112 through the oil passage 356. Supply to chamber 333. Then, when the duty ratio starts to decrease gradually, the oil pressure in the oil passage 260 starts to increase, so that the clutch 3
The engagement force of 0 increases and the hydraulic chamber of the fifth switching valve 112 increases.
The pressure in 333 also increases, and when the oil pressure acting on the pressure receiving surface on the left side of the land 328 and the biasing force of the spring 334 exceed the oil pressure acting on the pressure receiving surface on the right side of the land 330, the spool 332 is displaced to the right end position in the drawing. , The oil passage 314 communicates with the discharge port 335,
The spool 284 of the first switching valve 104 is surely displaced to the left so that the oil passage 288 does not communicate with the discharge port 287. When the duty ratio is 0%, that is, when the first solenoid valve 116 is demagnetized, the oil pressure in the oil passage 260 and the oil passage 288 becomes the second line pressure, and the clutch 30 corresponds to the second line pressure. The first speed gear stage is achieved by engaging with the resultant force.

Since the second line pressure is supplied to operate the clutch 30 and the brake 44 in the state where the first speed gear stage in which a relatively large torque is transmitted is achieved, the engagement of the brake 44 and the clutch 30 is increased. The resultant force is increased and a relatively large torque can be transmitted.

Next, when the vehicle starts traveling and the electronic control unit 124 determines that it is necessary to shift up to the second gear based on the throttle opening signal, the vehicle speed, etc., the electronic control unit 124
The first solenoid valve 116 is kept in the demagnetized state, and the second solenoid valve 118 is kept in the excited state.
The solenoid valve 120 has a duty ratio of 100%, that is, the duty ratio is gradually reduced from the completely excited state to finally reach 0%.
At the same time, the duty ratio of the fourth solenoid valve 122 is 0%, that is, a signal for gradually increasing the duty ratio from the completely demagnetized state to finally reaching 100% is output.

Since the first solenoid valve 116 is held in the non-excited state,
The clutch 30 is also kept in the engaged state, and the second solenoid valve 118 is kept in the excited state.
The state in which communication with and is blocked is maintained.

Since the fourth solenoid valve 122 is controlled so that the duty ratio increases from the state where the duty ratio is 0% (demagnetization),
When the oil passage 184 starts to communicate with the discharge port 150, the hydraulic pressure in the oil passage 184 decreases, and the spool 266 is gradually displaced rightward in the drawing. Therefore, the oil passage 278 communicates with the discharge port 273, and the oil pressure in the oil passage 278 starts to gradually decrease. Therefore, the oil pressure in the oil passage 358 communicating with the oil passage 278 via the sixth switching valve 114 also. And the engaging force of the brake 44 begins to decrease. Further, since the oil pressure in the oil passage 224 communicating with the oil passage 358 is also reduced, the oil pressure acting on the pressure receiving surface 216 of the pressure regulating valve 88 is reduced, and the spool 220 is balanced at the position where the oil pressure in the oil passage 202 is reduced. To do. Then, when the duty ratio further increases, the hydraulic pressure in the oil passages 278 and 358 further decreases, the engagement force of the brake 44 further decreases, and the brake 44 is finally released.
Further, the pressure in the oil passage 202 is also reduced and finally converges to the first line pressure (duty ratio 100%).

Since the duty ratio of the third solenoid valve 120 is gradually reduced from the state of being excited at the duty ratio of 100%, the oil passage 276 communicated with the discharge port 271 is gradually communicated with the oil passage 206. The oil pressure in the oil passage 276 also gradually rises and is guided to the fourth switching valve 110, and part of the oil pressure is guided to the brake 54 through the oil passage 312, the third switching valve 108, and the oil passage 316, and the same brake 54. Gradually operate in the engaging direction and
Part of the hydraulic pressure guided to 312 is oil passage 360, ball valve 362, oil passage 3
It is guided to the hydraulic chamber 295 of the second switching valve 106 via 64. Further, the other part of the hydraulic pressure introduced to the fourth switching valve 110 is
It is guided to the hydraulic chamber 391 of the sixth switching valve 114 via the hydraulic pressure 368, the ball valve 370 and the oil passage 372. Then, when the duty ratio further decreases and the hydraulic pressure in the oil passage 276 further increases, the engaging force of the brake 54 further increases and the first switching valve
When the hydraulic pressure in the hydraulic chamber 295 of 106 and the hydraulic chamber 391 of the sixth switching valve 114 rises, and the resultant force of the hydraulic pressure and the biasing force of the spring 296 or 342 exceeds the hydraulic pressure in the hydraulic chamber 293 or 339, the spool 294 is displaced to the right in FIG. 2 and the spool 340 is displaced to the left to communicate the oil passage 300 and the discharge port 297, and the oil passage 358 and the discharge port 343 to discharge the residual pressure in the oil passages 300 and 358. .

Furthermore, the duty ratio of the third solenoid valve 120 is 0%.
When it becomes (demagnetized), the brake 54 is engaged with the engaging force corresponding to the first line pressure.

Next, when the vehicle speed further increases and the electronic control unit 124 determines that the second speed to the third speed should be upshifted, the electronic control unit 124 demagnetizes the first solenoid valve 116, and , The fourth solenoid valve 122 is kept in the excited state, and the duty ratio of the third solenoid valve 120 is 0% (in the demagnetized state) in the same manner as the fourth solenoid valve 122 in the shift from the first speed to the second speed. ) To finally reach 100% (excitation state), and the third solenoid valve 120 in the shift from the first speed to the second speed is changed.
Similarly, the duty ratio of the second solenoid valve 118 is gradually decreased from 100%, and finally a signal for making it 0% is output.

Since the first solenoid valve 116 is maintained in the demagnetized state, the communication state between the oil passage 206 and the oil passage 288 is determined by the first hydraulic control valve 9
6, maintained via the oil passage 260, the first switching valve 104, the clutch 30
Are held in the engaged state. Also, the fourth solenoid valve 122
Is kept excited, the oil passage 278 and the discharge port 273
And are maintained in communication with each other, and the brake 44 does not operate.

In addition, since the third solenoid valve 120 is operated at a duty ratio that gradually increases from 0%, the spool 264 of the third hydraulic control valve 100 gradually becomes balanced on the right side of the drawing, and the oil passage 276. The hydraulic pressure inside begins to escape from the discharge passage 271. Therefore, in the oil passage 276, the fourth switching valve 112, the oil passage 326,
The engaging force of the brake 54 communicating via the fifth switching valve 112, the oil passage 314, the third switching valve 108, and the oil passage 316 gradually decreases, and at the same time, the hydraulic pressure in the hydraulic chamber 295 of the second switching valve 106 also decreases. ,spool
294 is displaced to the left and the oil passage 298 and the oil passage 300 are in communication with each other. Then, as the duty ratio approaches 100%, the hydraulic pressure in the oil passage 276 further decreases, the engagement force of the brake 54 further weakens, and finally the release state is established. here,
Since the brake 54 is communicated with the discharge port 335 via the oil passage 316 third switching valve 108, the oil passage 314, and the second switching valve 112, malfunction of the brake 54 is prevented.

On the other hand, the signal to the second solenoid valve 118 has a duty ratio of 100.
%, The spool 262 gradually becomes balanced on the left side of the drawing, and the oil passage 274 is changed to the oil passage 206.
The hydraulic pressure in the oil passage 274 gradually rises and is guided to the hydraulic chamber 321 of the fourth switching valve 110, the hydraulic chamber 341 of the sixth switching valve 114, and the hydraulic chamber 309 of the third switching valve 108. With second switching valve
It is also guided to the clutch 28 via 106 and operates the clutch 28 in the engaging direction. When the duty ratio further decreases, the spool 322 of the fourth switching valve 110 and the sixth switching valve 11
The spool 340 of 4 is displaced to the left in the drawing, and the spool 308 of the third switching valve 108 is displaced to the right of the drawing, so that the oil passage 276, the oil passage 326, the oil passage 358, and the discharge port 343 (the brake 44 malfunctions). Oil passage 314 and oil passage 316, and oil passage 312 and discharge port
The 311 are communicated with each other, and the engaging force of the clutch 28 is increased. Then, when the duty ratio becomes 0%, the clutch is engaged with the engaging force corresponding to the first line pressure, and the third speed gear stage is achieved.

Further, the vehicle speed increases and the electronic control unit 124
When it is determined that the gear shift from the fourth gear to the fourth gear should be performed, the electronic control unit 124 holds the second solenoid valve 118 in the demagnetized state and the fourth solenoid valve 122 in the excited state. , A signal for gradually increasing the duty ratio of the first solenoid valve 116 from 0% to finally 100%, and gradually decreasing the duty ratio of the third solenoid valve 120 from 100% to finally 0%. Is output.

Since the second solenoid valve 118 is maintained in the demagnetized state, the communication state between the oil passage 206 and the oil passage 274 is maintained, and the third solenoid valve 118 is maintained.
As in the case of achieving the high speed shift, the first line pressure in the oil passage 274 causes the hydraulic chamber 309 of the third switching valve 108, the hydraulic chamber 321 of the fourth switching valve 110, and the oil passages 374, 372 via the oil passage 372. Through the sixth switching valve 114
Of the spool 30 of the third switching valve 108.
8 is held to the right in the drawing, the spool 322 of the fourth switching valve 110 is held to the left in the drawing, and the spool 340 of the sixth switching valve 114 is held to the left in the drawing. The oil pressure in the oil passage 274 is also guided to the clutch 28 via the oil passage 298, the second switching valve 106, and the oil passage 300, so that the clutch 28 is held in the engaged state.

Further, since the fourth solenoid valve 122 is held in the demagnetized state and the oil passage 278 continues to communicate with the discharge port 273 as in the case of achieving the third speed, the oil pressure is not generated in the oil passage 278. The oil passage 358 communicating with the brake 44 is the sixth switching valve 1
Since it communicates with 14 exhaust ports 343, the same brake 4
4 does not malfunction.

Since the signal that operates the first solenoid valve 116 is controlled so that the duty ratio gradually increases from 0%, the oil passage 17
The hydraulic pressure in 8 gradually decreases, the spool 248 of the first hydraulic control valve 96 balances on the right side of the drawing, and the oil passage 260 moves above the control valve 96.
Begin communicating with the exhaust port 251 of the. Therefore, the oil pressure in the oil passage 260 gradually decreases, and the first switching valve 104 and the oil passage 2 are connected to the oil passage 260.
The engagement force of the clutch 30 communicated via 88 gradually decreases, and the hydraulic pressure in the hydraulic chamber 333 of the fifth switching valve 112 communicated with the oil passage 260 via the oil passage 356 also decreases. When the duty ratio rises and the hydraulic pressure in the oil passage 260 further decreases, the engagement force of the clutch 30 further weakens and the hydraulic chamber
The hydraulic pressure in 333 decreases, the spool 332 is displaced to the left in the drawing, and the oil passage 326 and the oil passage 314 are in communication. When the duty ratio becomes 100%, the pressure in the oil passage 260 becomes 0 kg /
cm ² , and the clutch 30 is released.

On the other hand, the signal for operating the third solenoid valve 120 is controlled so as to gradually decrease from the duty ratio of 100%.
The hydraulic pressure in the oil passage 182 rises and the spool of the third hydraulic control valve 100
264 is balanced on the left side of the drawing, and oil passage 276 is discharge port 27.
The communication with 1 is cut off and communication with the oil passage 206 is started.
Therefore, the hydraulic pressure in the oil passage 276 is guided to the brake 54 via the fourth switching valve 110, the oil passage 326, the fifth switching valve 112, the oil passage 314, the third switching valve 108, and the oil passage 316, and the brake 54 Is applied to the hydraulic chamber 285 of the first switching valve 104.
Is also led to. When the duty ratio further decreases, the hydraulic pressure in the oil passage 276 increases, so the brake 54
When the combined force of the hydraulic pressure in the hydraulic chamber 285 and the urging force of the spring 286 exceeds the hydraulic pressure in the hydraulic chamber 283, the spool 284 is displaced to the right in the drawing and the oil passage is increased. 288
And the discharge port 287 communicate with each other to prevent malfunction of the clutch 30. When the duty ratio becomes 0%, the oil passage
The pressure in 274 becomes the first line pressure, and the brake 54 is engaged with the engaging force corresponding to the same line pressure to achieve the fourth speed gear stage.

The upshift operation from the first gear to the fourth gear has been described above, but the downshift operation from the fourth gear to the first gear is simply the upshift. Since the procedure is exactly the reverse of that, the description is omitted.

Further, when the selector lever is set to the 2 or L position, the gear shift is performed between the first gear and the second gear according to a command from the electronic control unit 124 or the first gear is set. Only the gear change control that is fixed to the gear is performed,
Since the hydraulic circuit is exactly the same as when the selector lever is set to the D position, the description will be omitted.

Next, when the driver of the vehicle operates the selector lever to select the R position and the manual valve 94 is set to the R position, the oil passage 202
Is in communication with the oil passage 208 and is disconnected from the oil passage 206. In addition, the electronic control unit 124 outputs a signal that brings all solenoid valves into a non-excited state. Oil passage 208 above
The hydraulic pressure guided to the clutch 32 is supplied to a hydraulic chamber (not shown) for operating the clutch 32 to bring the clutch 32 into an engaged state, and is guided to the pressure regulating valve 88 via the oil passage 226 to receive the pressure receiving surface 2
18 and further via the oil passage 376, the ball valve 352, the oil passage 354, the fourth hydraulic control valve 102, the oil passage 278, and the sixth switching valve 114.
58, oil passage 360, and oil passage 224, respectively.

The oil pressure guided to the oil passage 358 is supplied to a hydraulic chamber (not shown) for actuating the brake 44 to actuate the brake 44, and the oil pressure introduced to the oil passage 360 is the ball valve 362 and the oil passage 360.
Is guided to the hydraulic chamber 295 of the second switching valve 106 via the
Displace 294 to the right in the drawing and use the land 290 to oil line 29
8 is closed and the oil passage 300 and the discharge port 297 are connected to each other to prevent the clutch 28 from malfunctioning. Further, the hydraulic pressure guided to the oil passage 224 is supplied to the pressure regulating valve 88 and acts on the pressure receiving surface 216. Therefore, the hydraulic pressure acting on the pressure receiving surfaces 216 and 218 causes the oil passage 2
The hydraulic pressure in 02 is increased to the third line pressure, and the brake 44
Also, since the clutch 32 is relatively strongly engaged, a sufficient torque capacity of the above-mentioned brake and clutch can be ensured when the reverse gear is achieved in which a relatively large torque is transmitted.

Next, when a failure occurs in the electronic control unit 124, the control unit 124 detects the failure and turns off all the signals output to each solenoid valve, and sets all the spool valves of each hydraulic control valve to the left end position in the drawing. Shift to. Therefore, the position (D, 2, L) at which the manual valve 94 achieves at least the forward speed is established.
If the oil passage 202 is connected to the oil passage 206, the line pressure is guided to each hydraulic control valve via the oil passage 206, and the hydraulic pressure introduced from the first hydraulic control valve 96 to the oil passage 260 is , 5th switching valve 112
Of the spool 332 is displaced to the right in the drawing to block the communication between the oil passage 326 and the oil passage 314, and
It is guided to the clutch 30 via the switching valve 104 and the oil passage 228 to put the clutch 30 in the engaged state.

The oil pressure introduced to the second oil pressure control valve 98 passes through the oil passage 274,
Oil path 372, guided to the left end hydraulic chamber of the third switching valve 108, spool 3
08 is displaced to the right in the drawing, and is guided to the clutch 28 via the oil passage 298, the second switching valve 106, and the oil passage 300 to bring the clutch 28 into the engaged state, and the right end hydraulic pressure of the fourth switching valve 110 is also increased. Guided to the chamber and displaced spool 322 to the left in the drawing Oil passage 276
Communicates with the oil passage 326, and further includes an oil passage 374, a ball valve 370,
It is guided to the right end hydraulic chamber of the sixth switching valve 114 via the oil passage 372 and displaces the spool 340 to the left in the drawing, thereby blocking the communication between the oil passage 278 and the oil passage 358. Also, from the third hydraulic control valve 100 to the oil passage 2
The hydraulic pressure guided to 76 is guided to the fifth switching valve 112 via the fourth switching valve 110 and the oil passage 326. However, because the land 328 of the fifth switching valve 112 blocks the communication between the oil passage 326 and the oil passage 314, the oil pressure in the oil passage 326 is not guided to the oil passage 314. The hydraulic pressure guided from the fourth hydraulic control valve 102 to the oil passage 278 is guided to the sixth switching valve 114. However, since the communication between the oil passage 278 and the oil passage 358 is blocked by the land 338, the brake 44 does not operate.

Therefore, the electronic control unit 124 is out of order, and the manual valve 94 is
When it is set to the D, 2 or L position, the clutch 28 and the clutch 30 are in the engaged state, so that the third speed is achieved and the vehicle cannot run at all.

On the other hand, the electronic control unit 124 is out of order, and the manual valve 94 is R
When it is set to the position, as is clear from Table 2, the operation is exactly the same as achieving the reverse gear,
Since the clutch 32 and the brake 44 are operated, the reverse gear can be achieved when the electronic control unit 124 fails.

Up to now, for simplicity, the first solenoid valve 116 to the fourth solenoid valve
Although it has been described that the solenoid valve 122 is simply duty-controlled to gradually supply or discharge the hydraulic pressure at the time of shifting, the hydraulic control method for reducing the shift shock will be described below as the second method at power-on. A description will be given with reference to FIGS. 3 to 5 by taking an example of the gears from the third speed to the third speed.

3 (a), (b), and (c) show the engagement element to be released and the hydraulic pressure P1 supplied to the engagement element to be engaged.
P2, input shaft rotation speed Ni, and output shaft torque over time, FIGS. 4 (a) and 4 (b) are flow charts for controlling the hydraulic pressures P1 and P2, and FIG. b), the fourth above
It shows the relationship between the correction coefficients A and B and the corrected hydraulic pressure in FIG.

When the second gear is achieved, the second and fourth gears are
The solenoid valves 118 and 122 are in the ON state, the first and third solenoid valves 116 and 120 are in the OFF state, and the clutch 30 and the brake 50 are engaged by the engagement force of the first line pressure (hereinafter referred to as P1). Here, if the electronic control unit 124 determines that an upshift to the third speed gear stage is necessary based on the accelerator opening degree, the vehicle speed, etc., the control unit 124 issues a shift start command signal, and the third speed gear stage is issued. 4 to be described below, the control signals for controlling the hydraulic pressures P1 and P2 to the brake 54 that is released and the clutch 28 that is engaged (the clutch 30 is maintained in the engaged state) when achieving It is output to the third solenoid valve 120 and the second solenoid valve 118 based on the flowcharts shown in (a) and (b).

First, the control of the hydraulic pressure P1 supplied to the engagement element on the released side will be described with reference to FIG.

When a shift start command signal is issued from the electronic control unit 124, a program for controlling the hydraulic pressure P1 is started (step (1)) and is fixed to the transmission casing 22 by the brake 54 via the second intermediate shaft 48. In order to allow the relative rotation of the second sun gear 52 with respect to the casing 22, a step (2) of setting a predetermined initial oil pressure that is relatively lower than the first line pressure P1 is executed, and the release side oil pressure P1 is changed to the oil pressure Pa.
Step (3) and the P1 command step (4) of exciting the third solenoid valve 120 at the duty ratio corresponding to the hydraulic pressure P1 are executed. (Figure 3 area). Next, in step (5), the second sun gear 52 for the transmission casing 22 is
The rotational speed Ni of the input shaft 26 and the output gear rotational speed No (corresponding to the vehicle speed) generated by the relative rotation of the shaft are detected, and the shaft rotational speed Ni and the output gear rotational speed No are detected in step (6).
Then, the difference ΔNi between the product No × i2 of the second gear ratio i2 and the second gear ratio i2 is calculated. Then, in order to make the input shaft rotation speed Ni higher than the product of the output gear rotation speed No and the gear ratio i2 by a preset rotation speed (20 [rpm] in this embodiment), the same rotation speed and ΔNi Step (7) for calculating the difference ΔNv between the difference ΔNv and the straight line of the slope A, which is determined from the relationship between ΔNv and the straight line of the slope A, that is, the difference ΔNv.
The step (8) of determining the magnitude of ΔP1 in proportion to the magnitude of Nv, the step (9) of calculating the change rate Δv of ΔNv, and the straight line of Δv and the slope B shown in FIG. The step (10) of calculating the hydraulic pressure correction amount ΔP1 ′ determined from the relationship is executed. Next, in step (11), P1-Δ
P1 + ΔP1 ′ is calculated, and when ΔNv is positive, the hydraulic pressure is corrected so that the engaging force of the brake 54 is weakened because the measured value is smaller than the target value, and conversely, when the value is negative, the engaging force is increased. The correction amount ΔP1 is controlled in proportion to the magnitude of ΔNv, and further, when ΔNv is positive and Δv is positive (the measured value is gradually smaller than the target value), the engaging force is reduced. On the contrary, when ΔNv is positive and Δv is negative (the measured value is gradually approaching the target value), the engaging force should be increased in order to prevent overshoot.
When P1 ′ is controlled and ΔNv is negative and Δv is positive (the actual measured value is gradually larger than the target value), the engaging force is increased. Conversely, ΔNv is negative and Δv is negative. In the case of (the measured value is close to the target value), a new P1 is calculated so that the engaging force becomes small in order to prevent overshoot, and it is replaced with Pa. And
Unless the P1 is judged to be 0 in the judgment step (12), the above steps (4) to (12) are repeatedly executed and the third solenoid valve 120 is operated at the duty ratio corresponding to the P1. (Region of FIG. 3) On the other hand, when the engagement-side engagement element (clutch 28), which will be described later, starts initial engagement and, as a result, the input shaft rotation speed Ni starts to decrease, the same rotation speed Ni is changed to No × i2 + 20 [ [rpm], the hydraulic pressure to the brake 54 suddenly decreases and finally becomes zero. (Figure 3 area) Then, the above determination step (1
When it is determined that P1 = 0 in 2), the control of the hydraulic pressure P1 ends (step (13)).

In the above flowchart, steps (9), (1
In (0), the change rate Δ of ΔNi is calculated, ΔP1 ′ is calculated based on the same Δ and the coefficient B, and the hydraulic pressure supplied to the brake 54 is corrected, but the steps (9) and (10) are performed.
Is optional.

In the step (12), the same P1 is set until P1 becomes 0.
Feedback control was performed, but the hydraulic pressure at the time when the brake 54 is sufficiently released is obtained in advance,
It is also possible to stop the feedback control when P1 falls below the same hydraulic pressure obtained in advance, and then output a command to set P1 to 0.

Next, the control of the hydraulic pressure P2 supplied to the engagement element on the engaged side will be described based on FIG. 4 (b).

When a shift start command signal is issued from the electronic control unit 124, a program for controlling the hydraulic pressure P2 is started (step (14)), and first, the clutch 28 is actuated by an ineffective stroke (play) for the shortest possible time. A signal for operating the second solenoid valve 118 so that the line pressure or a hydraulic pressure close to the line pressure for moving to the initial engagement position is introduced to the clutch 28 for a predetermined time or just before the clutch 28 enters the initial engagement state. Is output until it is stroked to a predetermined position (region in FIG. 3, not shown in FIG. 4), and in step (15), the constant C2 and the timer set time Δt (for example, 50
[Msec]) and the addition value ΔP2 of P2 is determined. Then, in step (16), the initial hydraulic pressure Pb for holding the clutch 28 in the initial engagement state is set, and the engagement side hydraulic pressure P2 is set.
Is set to Pb and the P2 command step (18) of operating the second solenoid valve 118 at the duty ratio corresponding to the hydraulic pressure P2 is executed. Next, in step (19), the above timer is set to start back calculation, and in step (20), the input shaft rotation speed Ni and the output gear rotation speed No are detected,
In the determination step (21), it is determined whether or not the difference between Ni and the product of No and the gear ratio i2 of the second speed is a negative value, that is, the initial engagement of the clutch 28 is started and the release side is released. Ni is gradually reduced from the state in which the input shaft rotation speed Ni is controlled to be 20 [rpm] higher than when the second speed is achieved by the engagement element (in this case, the brake 54), It becomes lower than Ni corresponding to the second gear and it is judged whether the shift is started or not. If not, it is judged whether the remaining time of the timer set in step (19) becomes 0. The determination step (22) is performed. If NO, the step (22) is repeatedly performed until it becomes zero. And
When the remaining time of the timer reaches 0, the sum of P2 determined in step (17) and ΔP2 determined in step (15) is set as a new P2, that is, the clutch 28 is initially engaged. Therefore, step (23) of increasing the hydraulic pressure to the clutch 28 by ΔP is executed, and the process returns to step (18) again. The steps from step (18) to step (23) are repeatedly executed until the start of gear shift is detected in step (21). (Figure 3 area).

On the other hand, when it is determined in step (21) that the gear shift has started, the target rate of change Ns of the input shaft rotation speed Ni during gear shift is determined in step (24) by the accelerator opening, the gear position, the vehicle speed, and the input shaft rotation speed. The current input shaft rotation speed Ni is detected in step (25), and the actual change rate i of Ni is calculated in step (25). Then, the difference Δi between the target change rate s set in the step (24) and the actual change rate i calculated in the step (26) is calculated in step (27), and the difference Δi is calculated in step (28). And the gain γ are used to calculate the hydraulic pressure correction amount ΔP2, and the difference between the hydraulic pressure P2 finally commanded in step (18) and ΔP2 is calculated as a new P2
Then, step (29) is executed. Then, in step (30), the input shaft rotation speed Ni and the output gear rotation speed No are detected, and in the discrimination step (31), whether the product of the No. and the gear ratio of the third speed is smaller than the above Ni or not. That is, it is judged whether or not the third speed gear is not achieved and the gear is still in gear. If YES, from the above step (25) until the third speed gear is achieved. When the step (31) is repeatedly executed (region of FIG. 3) and the third speed is achieved, the hydraulic pressure P2 is set to the first line pressure P1 (step 32)
And a step (33) of outputting a signal (non-excitation signal) corresponding to the hydraulic pressure P2 set in the same step (32) to the second solenoid valve 118 (region (6) in FIG. 3), the hydraulic pressure P2
Control is completed (step (34)).

In the embodiment described above, the rotation speed of the input shaft 26 is Ni,
Also, the rotation speed of the output gear 64 was detected as No, but the rotation speed of the output shaft of the engine instead of the input shaft 26 and the rotation speed of the idler 70, the driven gear 68, etc. instead of the output gear 64 were detected. Even if it does, the same effect as the above-mentioned Example is produced.

Further, in the above embodiment, the case of shifting from the second speed to the third speed has been described, but it goes without saying that the same control can be applied to other upshift speeds. .

According to the configuration of this embodiment, when the electronic control unit 124 outputs the shift command signal, the hydraulic pressure P1 to the brake 54, which is the disengagement side engagement element, is reduced from the first line pressure P1 to the initial hydraulic pressure Pa. Then, the brake 54 is slid to perform feedback control so that the input shaft rotation speed Ni becomes 20 [rpm] higher than when the second speed is achieved. The reduction of the input shaft rotation speed Ni (start of speed change) due to the start of engagement of 28 can be achieved smoothly without the one-way clutch that is generally used in the past.

Also, in order to match the measured value (ΔNv) with the target value (20 [rpm]), not only the error magnitude (ΔNv) of the measured value with respect to the target value but also the change rate (ΔNv) of the error are matched.
Since the hydraulic pressure supplied to the engagement element is also corrected in proportion to v), the hydraulic pressure does not vibrate and cause hunting or divergence depending on the amount of correction.

Further, when the electronic control unit 124 fails, all solenoid valves are configured to be turned off, so that the third speed shift stage, the neutral shift speed and the reverse shift shift speed can be achieved, and the vehicle runs at all. It will never be disabled.

Further, according to the hydraulic control system of the present embodiment, the oil passage leading to the engagement element that is not involved in the achievement of the shift speed is configured to communicate with the discharge port by the switching valve, so that the solenoid valve fails or the like. As a result, the hydraulic pressure is supplied to the engaging elements that are not involved in achieving the shift speed, and the gear transmission is prevented from locking.

Further, in the present embodiment, each switching valve 104 except each hydraulic control valve 96 to 102, each solenoid valve 116 to 122, and the third switching valve 108 is used.
Since ~ 114 are configured by common parts, manufacturing cost can be kept low and erroneous assembly can be prevented.

Further, since the oil pump 86 is of a variable discharge type, it is possible to discharge only the minimum necessary amount of oil, and it is possible to reduce the load on the engine that drives the pump 86.

〔The invention's effect〕

According to the present invention, when the command signal is issued, the engagement force of the second engagement element that is released is controlled so that the rotation speed of the input shaft coincides with the target rotation speed that is higher by a predetermined value. When the start is detected, the engaging force of the first engaging element is controlled to a desired value, so that the first and second engaging elements may be in the completely engaged state at the same time. Therefore, the switching of the torque transmission path from the second engagement element to the first engagement element can be achieved smoothly without using a one-way clutch or the like, and the shift shock can be reduced.

[Brief description of drawings]

FIG. 1 is a power train diagram of an automatic transmission for a vehicle to which an embodiment of the present invention is applied, FIG. 2 is a circuit diagram showing a hydraulic control device of the automatic transmission, and FIG. 3 is a diagram of the automatic transmission. FIG. 4 shows the change characteristics of change elements that change during a gear change. In the figure, (a) is the hydraulic pressure, (b) is the input shaft rotation speed, and (c) is a graph showing the change characteristics of the output torque. FIG. 5 is a flowchart showing a control at the time of shifting in the embodiment, in which (a) is a flowchart showing a control process of the disengagement side engagement element, (b) is a flowchart showing a control process of the engagement side engagement element, and FIG. Is a graph for obtaining the corrected hydraulic pressure, (a) is a graph showing the error ΔNi between the target rotational speed of the input shaft and the actual rotational speed, and the relationship between the correction coefficient A and the corrected hydraulic pressure ΔP1, and (b) is the above error. The relationship between the change rate ΔNi and the correction coefficient A and the correction hydraulic pressure ΔP1 ′ It is a graph which shows a relation. 26 ... Input shaft, 28,30,32 ... Clutch, 44,54 ... Brake, 96,9
8,100,102 ... hydraulic control valve, 104,106,108,110,112,114 ... switching valve, 116,118,120,122 ... solenoid valve, 124 ... electronic control device

Claims (5)

[Claims] 1. An input shaft to which a driving force is transmitted, first and second engaging elements which can be selectively engaged, and a driving state for detecting that the driving force is transmitted to the input shaft. Detection means, shift command means for generating a shift command from a low speed stage to a high speed stage, and the first engagement element is engaged according to the output signal and the shift command signal from the drive state detection means and the second A shift control device for controlling the engagement force of the first engagement element and the second engagement element so as to release the engagement element of, and the shift control device outputs the shift command signal to the shift command signal. Correspondingly, first engagement force control means for increasing the rotation speed of the input shaft by reducing the engagement force of the second engagement element, and rotation speed of the input shaft for input shaft rotation before outputting the shift command signal. It matches the target rotation speed that is higher than the speed by a specified value. Second engagement force control means for controlling the engagement force of the second engagement element; effective gear shift start detection means for detecting that an effective gear shift has started due to engagement of the first engagement element; After the engagement is started according to the shift command signal and the effective shift start is detected by the effective shift start detecting means, the engaging force of the first engagement element is controlled to a desired value to engage the first engagement element. 3. A shift control device for an automatic transmission for a vehicle, comprising: 3 engaging force control adjusting means; 2. The engagement force of the second engagement element is the second engagement element.
By the engagement force control means, in proportion to a first value obtained by subtracting the target rotation speed from the actual rotation speed of the input shaft, and in the direction of increasing the engagement force when the first value is positive, and The shift control device for an automatic transmission for a vehicle according to claim 1, wherein, when the shift force is negative, the engagement force is controlled to be reduced. 3. The engagement force of the second engagement element is the second engagement element.
The input force is proportional to the first value obtained by subtracting the target rotation speed from the actual rotation speed of the input shaft and the second value indicating the rate of change of the actual rotation speed of the input shaft by the engagement force control means, and the input The control is such that when the rotational speed of the shaft deviates in the increasing direction, the engaging force is increased, and when the rotational speed deviates in the decreasing direction, the engaging force is decreased. A shift control device for an automatic transmission for a vehicle according to claim 1. 4. The third engagement force control means controls the engagement force of the first engagement element so that the rotational speed change rate of the input shaft matches a predetermined target value. A shift control device for an automatic transmission for a vehicle according to claim 1. 5. The automatic transmission for a vehicle includes an output shaft that outputs the driving force via the engagement element, and the input shaft rotation speed before the output of the shift command signal is at the low speed stage. The shift control device for an automatic transmission for a vehicle according to claim 1, wherein the shift control device is calculated from a product of a gear ratio and the output shaft rotation speed.