JPH0522097B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a control device for a vehicle transmission having an automatic transmission mechanism. (Prior Art) Conventionally, vehicle transmissions installed in two-wheel drive vehicles have an automatic transmission mechanism, which detects vehicle running conditions such as throttle opening and vehicle speed, and adjusts the throttle opening to a preset throttle opening. Shift control is performed based on the relationship between speed, vehicle speed, etc., and each gear stage. In addition, in the case of a vehicle transmission installed in a four-wheel drive vehicle, in addition to having the automatic transmission mechanism described above as a main transmission, an auxiliary transmission is connected to the rear of the main transmission. Depending on the machine, two-wheel drive high speed gear,
Three drive states, 4-wheel drive high-speed gear and 4-wheel drive low-speed gear, can be switched arbitrarily. When the vehicle is traveling on a rough road, the automatic transmission mechanism is set to a low gear in the case of a vehicle installed in a two-wheel drive vehicle, and the automatic transmission mechanism is set to a low gear in a vehicle installed in a four-wheel drive vehicle. The auxiliary transmission is set to a four-wheel drive low gear drive state to obtain large torque. (Problems to be Solved by the Invention) However, in the conventional vehicle transmission described above, while the vehicle is traveling on a rough road, it may enter a place where the grip force of the drive wheels decreases, such as a sandy or muddy ground. If this happens, the drive wheels will easily spin if the vehicle is driven with a large torque. In such cases, if the vehicle is equipped with a two-wheel drive vehicle, the automatic transmission mechanism must be set to high gear, and if the vehicle is a four-wheel drive vehicle, the sub-transmission mechanism must be set to the high gear. It is preferable to set the drive high speed gear or the four-wheel drive high gear gear to drive with a torque suitable for the grip force of the drive wheels. However, if you are inexperienced with driving, you may unconsciously press the accelerator hard and increase the throttle opening, causing the automatic transmission mechanism to downshift, causing the drive wheels to spin, and even reducing your driving ability. There is. The present invention solves the problems of the conventional vehicle transmission described above, and provides a control device for a vehicle transmission that can prevent the drive wheels from spinning when the vehicle enters a sandy or muddy area. The purpose is to provide. [Means for Solving the Problems] In order to solve the above problems, the first invention of the present invention provides a sensor 60 for detecting the output shaft rotation speed of the transmission.
1, a driving condition detecting means for detecting vehicle driving conditions including a sensor 602 for detecting the actual vehicle speed, and means 708 for setting a gear position corresponding to the vehicle driving condition detected by the driving condition detecting means. a transmission 10 that changes gears according to a set gear stage;
Calculate vehicle speed based on detected output shaft rotation speed 7
06, when the difference between the vehicle speed and the detected actual vehicle speed is larger than a predetermined value, it is determined that the driving wheels are in the idling state; and when it is determined that the driving wheels are in the idling state. The present invention has a configuration of a control device for an automatic transmission for a vehicle, characterized in that it includes means 711 for switching the setting to a gear position higher than the current gear position. Moreover, the second aspect of the present invention
The invention includes a first torque detecting means 607 that detects the transmission torque of a first output shaft that drives one of the front wheels and rear wheels of the vehicle, and a second torque detecting means 607 that detects the transmission torque of the first output shaft that drives either the front wheels or the rear wheels of the vehicle. A running condition detecting means for detecting vehicle running conditions, including a second torque detecting means 608 for detecting the transmission torque of the output shaft, and setting a gear position corresponding to the vehicle running condition detected by the running condition detecting means. means 805 for changing gears, and a transmission 10 for changing gears according to a set gear stage.
and an idling state detection means 815 that determines that the drive wheel is in an idling state when the difference between the detected transmission torque of the first output shaft and the transmission torque of the second output shaft is greater than or equal to a predetermined value; The control device for an automatic transmission for a vehicle is characterized in that it has a means 813 for switching the setting to a gear position higher than the current gear position when it is determined that the vehicle is idling. (According to the present invention, the driving condition detecting means for detecting the vehicle driving condition consisting of at least one parameter as described above is provided, and the driving condition detecting means detects the vehicle driving condition consisting of at least one parameter. A gear position is set, and the transmission is operated according to the set gear position to perform a gear change.Then, the vehicle driving condition detected by the driving condition detecting means is calculated to determine whether the drive wheels are in an idling state. In order to determine whether or not the wheel is idling, the vehicle is equipped with a idling state determining means, and when it is determined that the drive wheels are idling, the setting is switched to a gear position higher than the current gear position. Therefore, if the drive wheels spin while the vehicle is running, the transmission is controlled to shift up, which prevents the drive wheels from spinning when driving on rough roads such as sandy mud. (Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.
The figure shows the gear train. 10 is a 4-speed automatic transmission with overdrive that is a main transmission, and 40 is a 4-wheel drive transfer that is a sub-transmission connected to the output shaft 32 of the 4-speed automatic transmission 10. 4 wheel drive transfer 40
is attached to the 4-speed automatic transmission 10 attached to the engine E, the first output shaft 42 is connected to the rear wheel drive propeller shaft C, and the second output shaft 52 is connected to the front wheel drive propeller shaft B. . The 4-speed automatic transmission 10 includes a hydraulic torque converter T, an overdrive mechanism OD, and a forward speed 3.
Equipped with an underdrive mechanism UD with one reverse stage. The torque converter T includes a pump 11 connected to the output shaft of the engine E, a turbine 13 connected to the output shaft 12 of the torque converter T, a stator 15 connected to a fixed part via a one-way clutch 14, and a direct coupling clutch. The output shaft 12 of the torque converter T serves as the input shaft (12) of the overdrive mechanism OD. The overdrive mechanism OD includes frictional engagement elements such as a multi-disc clutch C ₀ , a multi-disc brake B ₀ and a one-way clutch F ₀ , and the selective engagement of these frictional engagement elements allows the components to be attached to a fixed member such as a transmission case. It consists of a planetary gear set P ₀ that is fixed to the input shaft, output shaft, or other components, or is released from the fixation or connection. The planetary gear set _P0 is connected to the input shaft (1
2), a ring gear 22 connected to the output shaft 25 of the overdrive mechanism OD, and a ring gear 22 rotatably fitted onto the input shaft (12) and fixed to the transmission case via the brake _B0. and a sun gear 23 connected to the carrier 21 via a clutch C ₀ and a one-way clutch F ₀ parallel to the clutch C ₀ ; It consists of a planetary pinion 24 meshed with 22. The output shaft 25 of the overdrive mechanism OD also serves as the input shaft of the underdrive mechanism UD, which has three forward stages and one reverse stage. The underdrive mechanism UD includes multi-disc clutches C1 and C2, which are frictional engagement elements, multi-disc brakes B1, B2 and B3, and a one-way clutch F1.
and F2 and front planetary gear set P1
and a rear planetary gear set P2. The rear planetary gear set P2 is the clutch C.
1 and the output shaft 3 of the underdrive mechanism UD.
2 and the input shaft (25) via a clutch C2.
A sun gear 34 is fixed to the transmission case via a brake B1, a brake B2 parallel to the brake B1, a one-way clutch F1 connected in series with the brake B2, and a sun gear 34 is rotatably supported by the carrier 33. and a planetary pinion 35 meshed with the ring gear 31. The front planetary gear set P1 is the brake B
3, a carrier 36 fixed to the transmission case via a one-way clutch F2 parallel to the brake B3, and the rear planetary gear set P2.
Sun gear 3 integrally formed with sun gear 34 of
7 and a ring gear 38 connected to the output shaft 32
and a planetary pinion 39 rotatably supported by a carrier 36 and meshed with a sun gear 37 and a ring gear 38. This four-wheel drive automatic transmission operates by controlling the hydraulic control device 100 of the four-speed automatic transmission 10 shown in FIG. Then, the brakes are selectively engaged or released, resulting in four forward automatic gear shifts including overdrive (O/D) and one reverse gear shift using only manual gear shifting. A shift lever (not shown) provided at the driver's seat for driving the manual valve of the hydraulic control device 100
has shift position SP in each range of P (parking), R (reverse), N (neutral), D (drive), S (second), and L (low),
Table 1 shows this shift position SP, the gear positions 4th speed 4, 3rd speed 3, 2nd speed 2, and 1st speed 1, and the operational relationships of the clutch and brake. In Table 1, ○ indicates engagement of the friction engagement element, blank indicates release, F (free) indicates free rotation of the one-way clutch, and L (lock) indicates engagement of the one-way clutch.

[Table] ○ in S1 and S2 indicates solenoid ON, and S
1, × in S2 indicates solenoid OFF. The hydraulic control device 100 of the 4-speed automatic transmission 10 includes:
Hydraulic pump 101, pressure regulating valve (regulator valve) 130, second pressure regulating valve 150, cooler bypass valve 105, pressure relief valve 106, reverse clutch sequence valve 110, throttle that generates throttle pressure according to throttle opening degree. valve 200, cutback valve 145, direct clutch control valve 120, manual valve 210, 1-2 shift valve 220, 2-3 shift valve 230, 3-4 shift valve 240, the 1-2 shift valve 220 and 3-4 shift Solenoid valve S that controls valve 240
2, 2-3 Solenoid valve S1 that controls the shift valve 230, solenoid valve S3 that controls the direct clutch control valve 120, intermediate coast modulator valve 245 that adjusts the oil pressure supplied to the brake B1, to the brake B3 A low coast modulator valve 250 that adjusts the supply oil pressure of the out clutch C1, an accumulator 260 of the clutch C1, an accumulator 270 of the out clutch C2, and a brake B2.
Accumulator 280, clutch C0, C
Flow control valves 301, 302, 303, 3 with check valves that control the flow rate of pressure oil supplied to each hydraulic servo of brakes B0, B1, and B2.
04,305,306, brake B0, B1, B
2, B3, B4 hydraulic servo B-0, B-1, B
-2, B-3, B-4, clutch C0, C1, C
2, C3, C4 hydraulic servo C-0, C-1, C
-2, C-3, C-4, and oil passages connecting the valves and the clutch and brake hydraulic cylinders. Hydraulic oil pumped up from the oil reservoir by the hydraulic pump 101 via the oil strainer is adjusted to a predetermined oil pressure (line pressure) by the pressure regulating valve 130 and then supplied to the oil path 1 . Pressure regulating valve 130 in oil line 1
and oil passage 1 connected via orifice 312
The pressure oil supplied to the second pressure regulating valve 150 via A is regulated to a predetermined torque converter pressure, lubricating oil pressure, and oil circulation cooler pressure in accordance with the throttle pressure output from the throttle valve 200. The pressure regulating valve 130 has a spring 131 on one side.
a spool 132 with a
The spool 132 has a plunger 138 connected in series in contact with the plunger 138, and the spool 132 is connected to the throttle pressure applied from one side to the small diameter land (lower land in the figure) of the plunger 138 from the oil passage 9 and the spring 13.
1, and when moving backward, it is further subjected to line pressure applied from the oil passage 5 to the plunger 138, and from the other side is subjected to the feedback pressure of the line pressure applied to the illustrated upper land 133 of the spool 132, and is displaced. , the communication area between the oil passage 1, the oil passage 1A, and the drain port 135 is adjusted to output line pressure to the oil passage 1 according to vehicle running conditions. The manual valve 210 is connected to a shift lever provided on the driver's seat, and is manually operated to switch between P (parking) and R according to the range of the shift lever.
(Reverse), N (Neutral), D (Drive),
Move to the S (second) and L (low) positions. Table 2 shows the communication state between oil passage 1 and oil passages 2 to 5 in each shift range of the shift lever. ○ indicates the case where line pressure is supplied through communication, ×
indicates a state where the pressure is exhausted.

[Table] In the throttle valve 200, a throttle plunger 201 strokes in response to the amount of depression of the accelerator pedal, and a spool 202 is moved via a spring 203 between the plunger 201 and a spool 202 on which a spring 204 is installed. The line pressure supplied from passage 1 is regulated to a throttle pressure according to the throttle opening and output to oil passage 9. The first solenoid valve S1 has an orifice 322
A high level solenoid pressure (equal to line pressure) is generated in the oil passage 2G that communicates with the oil passage 2 via the
When energized, the pressure oil in the oil path 2G is discharged to generate a low level solenoid pressure. When the second solenoid valve S2 is not energized, it generates high-level solenoid pressure in the oil passage 2F that communicates with the oil passage 2 via the orifice 332, and when energized, it discharges the pressure oil in the oil passage 2F and generates a low-level solenoid pressure. . The third solenoid valve S3 controls the oil pressure in the illustrated upper end oil chamber 121 of the direct coupling clutch control valve 120, which communicates with the oil passage 1H through the orifice 342. When not energized, this solenoid valve S3 generates a high-level solenoid pressure in the upper end oil chamber 121 and presses the spool 122 downward in the drawing together with a spring 123 installed behind it, positioning the spool 122 in the downward direction in the drawing, and energizing the solenoid valve S3. At times, the pressure in the upper end oil chamber 121 is evacuated to reverse the solenoid pressure to a low level. The 1-2 shift valve 220 has a spring 22 on the left side in the figure.
1, and when the solenoid valve S2 is de-energized and high-level solenoid oil pressure is generated in the oil passage 2F, the oil chamber 22 at the right end in the figure is provided.
4, high level solenoid pressure is applied to the hydraulic pressure, and the spool 222 is set to the left side as shown in the lower half of FIG. When the pressure is exhausted and the solenoid pressure is at a low level, the spool 222 is set to the right in the figure as shown in the upper half, and a position other than the first speed is obtained. In 3rd and 4th gears, the oil passage 2C is connected to the left end oil chamber 223 via the manual valve 210 and the 2-3 shift valve 230.
Line pressure is applied to the spool 222, and the spool 222 is fixed to the right in the figure regardless of the solenoid pressure. The 2-3 shift valve 230 has a spring 23 on the left side in the figure.
When the solenoid valve S1 is energized, the oil passage 2G becomes a low-level solenoid pressure, and the spool 232 is set to the right in the figure by the action of the spring 231, and the spool 232 is set to the right in the figure by the action of the spring 231, and the spool 232 is set to the right in the figure by the action of the spring 231. When the solenoid valve S1 is de-energized, high-level solenoid pressure is generated in the oil passage 2G and applied to the oil chamber 234, and the spool 232 is set to the left in the figure by the action of this solenoid pressure. The position is 3rd and 4th gear. When line pressure is supplied to the oil passage 4, the line pressure is supplied to the left end oil chamber 233, and the spool 232 is fixed to the right in the figure regardless of the solenoid pressure. The 3-4 shift valve 240 has a spring 24 on the left side in the figure.
When the solenoid valve S2 is de-energized, high-level solenoid pressure enters the right end oil chamber 243 through the oil path 2F, and the spool 242 is in the fourth speed (overdrive).
The solenoid valve S is fixed on the left side of the figure.
2 is energized, the pressure in the oil passage 2F is exhausted, and the spool 242 is set to the right in the figure by the action of the spring 241. manual valve 210, oil path 2 or oil path 3,
When line pressure is supplied to the left end oil chamber 244 through the 2-3 shift valve 230 and the oil passage 2B, the spool 242 is set to the right in the figure (other than 4th gear) due to the line pressure and the action of the spring 241. Ru. Next, the operation of the hydraulic control device 100 by manual shifting of the manual valve 210 will be explained. When manual valve 210 is set to N range or P range. As shown in Table 2, oil passage 1 does not communicate with any of oil passages 2 to 5, and as shown in Table 1 above, oil passage 1 does not communicate with any of oil passages 2 to 5.
Both solenoid valves S1 and S2 are de-energized. For this reason, the 1-2 shift valve 220, 2-
The spools 222, 232, 242 of the 3-shift valve 230 and the 3-4 shift valve 240 are all positioned to the right in the figure by the action of springs. Manual valve 2
Only the clutch C0, which is directly connected to the oil passage 1 through the 3-4 shift valve 240, the oil passage 1J and the flow control valve with check valve 301, is engaged. When manual valve 210 is set to D range. As shown in Table 2, oil pressure is supplied to the oil passage 2, which causes the flow rate control valve with check valve 302 and the oil passage 2E to
Clutch C1 is engaged. In the first gear when the vehicle starts, as shown in Table 1, the solenoid valve S1 is energized, the solenoid valve S2 is de-energized, and the spool 222 of the 1-2 shift valve 220 is located on the left side in the figure and is connected to the brakes B1 and B2. Since the oil passages 2A and 3A connected to the brake B3 are discharged and no oil pressure is supplied to the oil passage 4C connected to the brake B3, the brakes B1, B2, and B3 are released and the 2-
The spool 232 of the 3-4 shift valve 230 is set to the right in the figure, and is connected to the left end oil chamber 24 of the 3-4 shift valve 240.
Since line pressure is supplied to oil passage 4 through oil passage 2B, spool 242 is set to the right in the figure, and engages with clutch C ₀ through oil passages 1, 3-4 shift valve 240, and oil passage 1J. Since line pressure is supplied to the oil passage 2B, the oil passage 2C is depressurized and the outclutch C2 is released.Since line pressure is supplied to the oil passage 1J, the oil passage 1L is depressurized and the brake B is released.
0 is released, and as described above, first speed running is performed. When the vehicle speed reaches a preset value, the solenoid valve S2 is energized by the output of the electronic control device 600, and the solenoid pressure applied to the right end oil chamber 224 is reversed to a low level, so that the 1-2 shift valve 22
The spool 222 of No. 0 moves to the right in the figure, and oil pressure is supplied through the oil path 2, the 1-2 shift valve 220, the oil path 2A, the flow control valve with check valve 306, and the oil path 2H, and the brake B2 is engaged. An upshift to second gear occurs. To upshift to third gear, when the vehicle speed, throttle opening, etc. reach predetermined values, the solenoid valve S1 is de-energized by the output of the electronic control unit 600, and the spool 232 of the 2-3 shift valve 230 moves to the left in the figure. and oil passage 2, 2-3 shift valve 230, oil pusher 2C,
Hydraulic pressure is supplied through the flow control valve with check valve 303 and the oil path 2D, and the outclutch C2 is engaged.
At the same time, the spool 222 of the 1-2 shift valve 220 is set to the right side in the figure (other than the first speed) by the line pressure supplied from the oil passage 2C to the left end oil chamber 223. For upshifting to 4th speed, the solenoid valve S2 is de-energized by the output of the electronic control device 600 as described above, the solenoid pressure that was being supplied from the oil passage 2F to the right end oil chamber 243 is reversed to a high level, and the 3-4 The spool 242 of the shift valve 240 moves to the left in the figure, the pressure in the oil passage 1J is exhausted and the oil pressure is supplied to the oil passage 1L, and the clutch C0 is released and the brake B0 is engaged. When manual valve 210 is set to S range. As shown in Table 2, line pressure is supplied to oil passage 3 in addition to oil passage 2. 1st, 2nd, and 3rd gears are shifted in the same way as in the D range, but the left end of the 3-4 shift valve 240 is passed through oil path 2 or 3, the 2-3 shift valve 230, and the oil path 2B. Since line pressure enters the oil chamber 244 and the spool 242 is set to the right in the figure, a shift to fourth speed is prevented. In addition, in the second speed, C0,
Line pressure is supplied to C1 and B2, and oil passage 3
Line pressure is supplied from the 2-3 shift valve 230, oil passage 3A, 1-2 shift valve 220, and oil passage 3B to the intermediate eight coast modulator valve 245, so that the intermediate eight coast modulator valve 245 The hydraulic pressure regulated by the regulator valve 245 is supplied to the oil passage 3C, the brake B1 is engaged, and the second speed in which both the brake B2 and the brake B1 are constantly engaged is achieved, and the S range second speed is coasting. At times, the engine brake works and the transmission torque capacity increases. Furthermore, if the manual valve 210 is in the D position and a D-S shift is performed manually while driving in fourth gear, line pressure is introduced into the left end oil chamber 244 of the 3-4 shift valve 240 as described above, so that the third When the speed is reduced to a predetermined speed, the output of the electronic control unit 600 energizes the solenoid valve S1, causing a 3-2 downshift, and obtaining the second speed in which the engine brake is applied. When manual valve 210 is set to L range. As shown in Table 2, in addition to oil passage 2 and oil passage 3, oil passage 4
Line pressure is also supplied to the 1st and 2nd speed are D above
The same shift as in the range is made, but oil line 4
Line pressure enters the left end oil chamber 233 of the 2-3 shift valve, and the spool 232 is set to the right in the figure, so no shift to third speed occurs. In addition, the first speed is oil passage 4, 2-3 shift valve 230, oil passage 4A, low coast modulator valve 250, oil passage 4B, 1-2
The brake B3, which has a double piston of an inner piston and an outer piston, is engaged by hydraulic pressure supplied through the shift valve 220 and the oil passage 4C, thereby applying engine braking. Second
The speed is the same as when the manual valve 210 is shifted to the S range. Also, when manually shifting to L range while driving in 3rd gear, the above 2-
By introducing line pressure into the left end oil chamber 233 of the 3rd shift valve 230, a downshift is immediately performed to the 2nd speed, and when the speed has been reduced to the scheduled speed, the output of the electronic control unit 600 energizes the solenoid valve S2, and the 2- 1 downshift. Manual valve 210 is D or S, S or L
is shifted to each range, line pressure is generated in the oil passage 2, and the 1-2 shift valve 220 is shifted to the right side in the figure (the first
If the oil pressure is set to a speed other than the engine speed), line pressure is generated in the oil passage 2A and is supplied to the lower end oil chamber 124 of the direct coupling clutch control valve 120. Along with this line pressure, the third solenoid valve S3 is energized and the upper end oil chamber 12
1 is at a low level, the spool 122 of the direct coupling clutch control valve 120 is moved upward in the figure, and the oil passages 1A and 1D communicate with each other.
are engaged, and the torque converter T is in a directly connected state. When line pressure is not generated in the oil passage 2A, or even if line pressure is generated in the oil passage 2A, the solenoid valve S3 is de-energized and high-level solenoid pressure is generated in the upper end oil chamber 121, the spring 123 or the spring 123 Due to the action of the high level solenoid pressure, the spool 122 is positioned at the lower position in the figure. Spool 12
2 is located at the lower side in the figure, the oil passage 1A is in communication with the oil passage 1C, and the direct coupling clutch 16 in the torque converter T is released. When manual valve 210 is set to R range. As shown in Table 2, oil passages 2, 3, and 4 are depressurized and oil pressure is supplied to oil passage 5. Since line pressure is not supplied to the oil passages 2 and 3 communicating with the clutch C1 and the brakes B1 and B2, the clutch C1 and the brakes B1 and B2 are released. The hydraulic pressure supplied to the oil passage 5 is applied to the spool 2 of the 1-2 shift valve 220.
22 is set to the right in the figure by the action of the spring 221, the brake B3 having a double piston is engaged via the oil passage 4C, and the 2-3 shift valve 230
Since the spool 232 is set to the right in the figure by the action of the spring 231, the outclutch C2 is engaged through the oil passage 2C, the flow control valve with check valve 303, and the oil passage 2D, and the oil is supplied to the oil passage 2D. The left end oil chamber 1 of the reverse clutch sequence valve 110 is
14, the spool 112 is set to the right side in the figure, and the oil pressure in the oil passage 5 is applied to the ink latch C2.
engage. Since the spool 242 of the 3-4 shift valve 240 is set to the right in the figure by the action of the spring 241, the clutch C0 is engaged through the oil passage 1J supplied from the oil passage 1, and the brake B0 is connected. Since the pressure in the oil passage 1L is exhausted, the brake B0 is released and the vehicle travels in reverse (reverse) as described above. The transfer 40 in FIG. 2 has a clutch C3, a brake B4, and a clutch C4, which are frictional engagement elements, and an output shaft 32 of a planetary gear set P1, P2 as input shafts, and is arranged in series with the input shaft (32). The first output shaft 4 of the transferred transfer 40
2, a planetary gear set Pf disposed between the input shaft (32) and the first output shaft 42;
a four-wheel drive sleeve 51 rotatably fitted around the output shaft 42; a second output shaft 52 arranged parallel to the input shaft (32) and mounted in the opposite direction to the first output shaft 42; A transmission mechanism 53 is provided between the sleeve 51 and the second output shaft 52. The planetary gear set Pf includes a sun gear 44 spline-fitted to the end of the input shaft (32);
a planetary pinion 45 that meshes with the planetary pinion 45; a ring gear 46 that meshes with the planetary pinion 45; and a ring gear 46 that rotatably holds the planetary pinion 45 and the first output shaft 42 of the transfer shaft 40.
It consists of a carrier 47 connected to the tip of. In this embodiment, as shown in FIG. 4, the brake B4 is a multi-disc friction brake for engaging the ring gear 46 with the transfer case 48. It is operated by a hydraulic servo B-4 consisting of a piston 49P mounted on the hydraulic servo B-4. Clutch C3 is arranged on the 4-speed automatic transmission 10 side of planetary gear set Pf, and connects sun gear 44 and carrier 47.
The hydraulic servo C-3 is operated by a hydraulic servo C-3, which is composed of a cylinder 50 connected to the cylinder 50 and a piston 50P mounted inside the cylinder 50. The clutch C4 is a multi-disc friction clutch for connecting the first output shaft 42 connected to the carrier 47 and the sleeve 51 connected to one sprocket 56 of the transmission mechanism 53 for driving the second output shaft 52 of the transfer 40. The clutch is actuated by a hydraulic servo C-4, which is comprised of a cylinder 58 rotatably supported by the transfer case 48 and a piston 58P mounted within the cylinder 58. The transmission mechanism 53 includes a sprocket 56 formed on the sleeve 51, a second
It consists of a sprocket 55 spline-fitted to the output shaft 52 and a chain 57 stretched between these sprockets 55 and 56. A parking gear 59 is provided around the outer circumferential side of the cylinder 50 of the hydraulic servo C-3, and when the shift lever of the 4-speed automatic transmission 10 is selected to the parking position, the pawl engages the parking pawl (not shown). The meshing fixes the first output shaft 42. 60 is clutch C3, C4 of transfer 40
and brake B4 hydraulic servo C-3, C-4
and a transfer valve body provided with a hydraulic control device for supplying and discharging hydraulic pressure to B-4, and 61 is its oil pan. The hydraulic pressure supplied to the hydraulic servos C-3, C-4 and B-4 of the clutches C3 and C4 and the brake B4 is transferred to the transmission case 62 and the transfer case 48 through oil passages 64 provided in the transfer case 48. Control device 40
Transfer valve body 6 provided with 0
It leads to 0. During normal driving, the line pressure supplied to the hydraulic control device 100 of the 4-speed automatic transmission 10 is supplied to the hydraulic servo C-3 to engage the clutch C3, and the hydraulic servos B-4 and C-4 are exhausted. Brake B
4 and clutch C4 are released. As a result, the sun gear 44 and carrier 47 of the planetary gear set Pf are connected, and the power is transferred to the input shaft (32).
2-wheel drive running with only the rear wheels in which the reduction ratio is 1 is transmitted to the first output shaft 42 is obtained. At this time, the power from the input shaft (32) is transmitted to the first output shaft 4 from the carrier 47 via the clutch C3 without passing through the sun gear 44, planetary pinion 45, or ring gear 46.
2, no load is applied to the tooth surfaces of each gear, increasing the life of the gears. When four-wheel drive driving becomes necessary during this two-wheel drive driving, the shift lever 401 provided on the driver's seat etc. is manually shifted, and line pressure is gradually supplied to the hydraulic servo C-4 of the transfer control device 400. When the clutch C4 is smoothly engaged, the first output shaft 42 and the sleeve 51 are connected, and the transmission mechanism 53, the second output shaft 52, and the front wheel drive propeller shaft B (shown in FIG. 1) are connected.
The power is also transmitted to the front wheels via the input shaft (32) to the first output shaft 42 and the second output shaft 52 at a reduction ratio of 1, and the vehicle is in a four-wheel drive direct-coupled driving state (high-speed four-wheel drive state). is obtained. During this four-wheel drive driving, when the shift lever 401 is manually shifted when an increase in output torque is required, such as on a steep slope, the hydraulic pressure is applied to the hydraulic servo, which is a switching valve between a high-speed four-wheel drive state and a low-speed four-wheel drive state. By activating the inhibitor valve 440 and the accumulator control valve 460, which is a spool valve, line pressure is gradually supplied to the hydraulic servo B-4, and at the same time, the hydraulic pressure of the hydraulic servo C-3 is discharged at an appropriate timing, and the brake B4 is gradually applied. Clutch C3
be released smoothly. As a result, sun gear 44 and carrier 47 are released, ring gear 46 is fixed, and power is transmitted from the input shaft (32) to sun gear 44, planetary pinion 45, and carrier 4.
7 and is transmitted to the first output shaft 42 and the second output shaft 52, thereby obtaining a four-wheel drive decelerated driving state (low-speed four-wheel drive state) with large torque. Table 3 shows the setting range of the manual shift of the transfer 40, the engagement and release of the brake B4, the clutches C3 and C4, and the running condition of the vehicle.

[Table] In Table 3, ○ indicates the engaged state of the friction engagement element, and × indicates the released state. The reduction ratio (3.0 in the example) is
The ratio of the number of teeth between the sun gear 44 and the ring gear 46 of the planetary gear set Pf is λ, and the reduction ratio is calculated as follows: (1+λ)/λ=3.0, where λ is 0.5. Transfer control device 40 of transfer 40
0 is a transfer manual valve 410 connected to a shift lever 401 provided in the driver's seat via a link mechanism 402, and an inhibitor for switching between high speed (direct connection) and low speed (deceleration) during four-wheel drive. valve 440 and the inhibitor valve 440
an upshift (L4→H4 shift) timing mechanism 430, which is provided between the hydraulic servo C-3 and the accumulator control valve 460, an accumulator 490, and a throttle 491, and an oil passage connected to the oil passage 1. 1M to said inhibitor valve 44
0 input oil pressure (hydraulic pressure related to vehicle speed) and automatically switches between high speed and low speed of four-wheel drive when the vehicle speed exceeds a set value, and a hydraulic servo. A check valve equipped throttle 520 provided in the hydraulic oil supply/discharge path 1N to the hydraulic servo C-4, a check valve equipped throttle 530 provided in the hydraulic oil supply/discharge path 7 to the hydraulic servo C-4,
It consists of an inhibitor valve 440 and a check valve-equipped throttle 540 provided in the communication oil passage 1P with the upshift timing mechanism 430. The transfer manual valve 410 has a spool 420 connected to a shift lever 401 provided at the driver's seat via a link mechanism 402, and is connected to a line pressure generating oil path of the hydraulic control circuit of the four-speed automatic transmission 10. import 411, contacting 1;
Out port 413 communicating with oil passage 6, Out port 415 communicating with oil passage 7, Drain port 4
Transfer manual valve 410 having 17,419 connects oil passage 1 and oil passage 6 and connects oil passage 7 to drain port 419 when spool 420 is set to the two-wheel drive (H2) position, When set to 4-wheel drive high gear (H4) position, oil passage 1 is connected to oil passage 6 and oil passage 7, and when set to 4-wheel drive low gear (L4) position, oil passage 1 is connected.
and oil passage 7, and oil passage 6 is connected to drain port 4.
17 will be contacted. The inhibitor valve 440 has a spool 441 on which a spring 450 is placed on its back from the lower side in the drawing, and a puller 442 connected in series with the spool 441. Both spools 441 have the same diameter and a sleeve at the lower end on which a spring 450 is placed on its back. It has a shaped land 445, an illustrated upper end land 447, and an intermediate land 446. The plunger 442 has a lower end land 448 shown in the drawing having a larger diameter than the land of the spool 441, and an upper end land 449 having a larger diameter than the lower end land 448. These spool 441 and plunger 442 provide a lower end oil chamber 451, first and second intermediate oil chambers 45 between the sleeve-shaped land 445, intermediate land 446 and upper end land 447.
2,453, spool 441 and plunger 442
An oil chamber 454 between the two and an upper end oil chamber 456 are formed. This inhibitor valve 440 is connected to a lower end oil chamber 451 when the spool 441 is set upward in the figure.
communicates with the vehicle speed pressure oil passage 1M via the oil port 443 of the sleeve-shaped land 445, the first intermediate oil chamber 452 communicates with the line pressure oil passage 1 and the deceleration oil passage 1N, and the second
The intermediate oil chamber 453 communicates with the direct connection oil passage 1P and the drain port 457, and when the spool 441 is set downward in the figure, the lower end oil chamber 451 communicates with the drain port 458 via the oil port 443 of the slube-shaped land 445. The first intermediate oil chamber 452 communicates between the deceleration oil passage 1N and the drain port 459, and the second intermediate oil chamber 453 communicates the dry pressure oil passage 1 with the direct connection oil passage 1W, and the oil chamber 454 is always connected to the vehicle. It communicates with the oil passage 1M for generating oil pressure related to speed, and the upper end oil chamber 456 always communicates with the oil passage 6. The accumulator control valve 460 has a spool 471 on which a spring 470 is mounted on its back in the lower part of the figure.
3 and an intermediate land 475, and an upper end land 477 with a larger diameter by a predetermined dimension than these two lands 473, 475, and the lower end oil chamber 4
61, intermediate oil chamber 463, 465, upper end oil chamber 467
is formed. This accumulator control valve 460
The lower intermediate oil chamber 463 always communicates with the oil passage 1Q that communicates with the servo C-3, and the upper intermediate oil chamber 465
is always in communication with the line pressure oil passage 1, and the upper end oil chamber 467
The oil pressure in the oil passage 1Q is fed back, and the lower end oil chamber 461 has a throttle 491 and an accumulator 49.
Hydraulic pressure is supplied from the oil passage 1R, which communicates with the oil passage 1Q via the oil passage 1Q. The automatic transfer control mechanism 500 includes an output shaft rotational speed sensor 601 of the transferor 40, an electronic control device 600 that receives the output of the output shaft rotational speed sensor 601, and an oil passage 1M connected to the oil passage 1. diaphragm 511 and the electronic control device 6
It consists of an electromagnetic solenoid valve S4 that is turned ON and OFF by the output of 00, and is turned OFF when the vehicle speed exceeds a set value (for example, 20 km/h) and the oil passage 1 is turned OFF.
Generates the line pressure of oil path 1 in M, and when it is below the set value, it is turned ON and discharges the oil pressure of oil path 1M. As a result, oil pressure related to the vehicle speed is generated in the oil path 1M. The ON/OFF settings of the solenoid valve S4 can be easily changed by the electronic control device 600 that controls the solenoid valve S4 based on, for example, an input signal from the output shaft speed sensor S601, so that the driver can easily change the ON/OFF setting values based on the road conditions, etc. It is easy to make changes according to the driving conditions of the vehicle. Line pressure enters the intermediate oil chamber 465 from passage 1,
The oil passage 7 is connected to a hydraulic servo C-4 via a check valve-equipped throttle 530. The operation of the transfer 40 in each setting range will be explained. (a) When the transfer manual valve 410 is set to the H2 range, the pressure in the oil passage 7 is exhausted, so no power is transmitted to the sleeve 51 and the two-wheel drive state is maintained. In addition, line pressure is supplied to the oil passage 6, the spool 441 and plunger 442 of the inhibitor valve 440 are set downward in the figure, and the oil passage 1N is connected to the drain port 459 and the pressure is exhausted, thereby the pressure of the brake B4 is exhausted, and the oil pressure is exhausted. Since passage 7 is depressurized, clutch C4 is depressurized. The oil passage 1P is connected to the oil passage 1, and is connected to the oil passage 1Q via a check valve-equipped throttle 540 and an accumulator control valve 460, thereby engaging the clutch C3. Therefore, the transformer 40 becomes H2 (two-wheel drive directly connected state). (b) When the transfer manual valve 410 is set to the H4 range, line pressure is supplied to both the oil passage 6 and the oil passage 7. The line pressure supplied to the oil passage 6 is set so that the spool 441 and the plunger 442 of the inhibitor valve 440 are set at the lower side in the figure, and the oil passage 1N is connected to the drain port 459 and the pressure is exhausted, and thereby the pressure of the brake B4 is exhausted. ing. The line pressure supplied to oil passage 7 engages clutch C4. As a result, the transfer gear 40 becomes H4 (four-wheel drive direct connection state). (c) When the transfer manual valve 410 is set to the H4 range, the oil passage 6 is depressurized, so the plansiar 442 is set upward, and since line pressure is supplied to the oil passage 7, the clutch C4
is engaged and the four-wheel drive state is maintained. Solenoid valve S4 turns OFF when the vehicle speed exceeds the set value
transfer manual valve 41 when
When 0 is set to the L4 range, line pressure is supplied to the oil path 1M. Therefore, the spool 441 of the inhibitor valve 440 remains set at the lower position in the drawing due to the line pressure applied to the oil chamber 454, and the gear is not changed, thereby preventing the engine E from overrunning. When the vehicle speed is below the set value and the solenoid valve S4 is turned on, the trough manual valve 410 is set to L.
4 range, or when the vehicle speed is above a predetermined value and the solenoid valve S4 is OFF, the transfer manual valve 410 is in the L4 state and the vehicle speed goes from above the set value to below the set value and solenoid valve S4 is turned off.
When it is turned on from OFF, the pressure in oil path 1M is exhausted, so the spool 441 is set upward in the figure by the action of spring 450, thereby connecting oil path 1 and oil path 1N and operating hydraulic servo B-4. Oil is supplied, and the oil passage 1P communicates with the drain port 457 to exhaust the pressure, thereby exhausting the hydraulic pressure of the hydraulic servo C-3 of the clutch C3. As a result, the transfer shaft 40 enters a low-speed four-wheel drive state. After the vehicle enters the low-speed four-wheel drive state, even if the vehicle speed exceeds the set value and the solenoid valve S4 is turned OFF, the line pressure of the oil passage 1M is applied to the oil chamber 454 of the inhibitor valve 440 and at the same time the spool 441 is turned off. Sleeve-shaped land 44
Since the oil is applied to the lower end oil chamber 451 through the oil port 443 of No. 5, the spool 441 is not displaced and the low-speed four-wheel drive state is maintained. Next, the first embodiment of the electronic control device 600 will be explained in the fifth embodiment.
This will be explained based on the block diagram shown in the figure. The electronic control device 600 controls the first transfer unit 40, which is a means for detecting wheel slippage of a four-wheel drive vehicle.
The output shaft rotational speed sensor 601 detects the rotational speed N of the output shaft 42, the actual vehicle speed sensor 602 detects the actual vehicle speed (V), and the setting position (SP) of the shift lever (not shown) provided at the driver's seat. Shift lever position sensor 603 to detect, throttle opening sensor 60 to detect throttle opening (θ)
4. Future input port 610, output port 611 to solenoid valves S1 to S4, central processing unit CPU, vehicle speed difference between actual vehicle speed (t) and vehicle speed (v) calculated from output shaft rotational speed (N) ( Read-only memory that stores the set value of the vehicle speed difference α
It consists of ROM and random access memory RAM that performs shift point processing. Next, this embodiment will be explained based on the flowcharts shown in FIGS. 6 and 7. Turn on the starter key, turn on the engine E (701), and perform initial settings to turn on the solenoid valve S1 and turn off the solenoid valve S2 so that the gear position of the 4-speed automatic transmission 10 is set to 1st speed (702) ).
Next, the output shaft rotation speed (N) from the output shaft rotation speed sensor 601 and the actual vehicle speed from the actual vehicle speed sensor 602.
(N), the set position of the shift lever (SP) from the shift lever position sensor 603, and the throttle opening (θ) from the throttle opening sensor 604 are input (703), and then the set position of the shift lever (SP) is input. ) is P (parking) range, R (reverse)
Determine whether the range is range or N (neutral) range (704), and select P range, R range, or N range.
When in the range, the solenoid valves S1 to S4 are set to OFF (705), and then returns (703).
When not in P range, R range or N range,
Convert the output shaft rotational speed N to vehicle speed (v) (706), |
It is determined whether actual vehicle speed (V) - vehicle speed (v) | is greater than a set value α stored in advance in the ROM (707), and |(V) -
(v) | When not α, performs gear change control according to vehicle speed (v) and throttle opening (θ) (708), then performs lock-up control to turn on or off solenoid valve S3 (709), and then By turning on and off the solenoid valve S4, the speed change control of the H4→L4 transfer 40 is performed (710).
After that, it returns to 703. When |V-v|>α,
It is determined that the slip is occurring, and the slip shift control shown in FIG. 7 is performed (711). The slip shift control first determines whether the gear stage of the 4-speed automatic transmission 10 is the first gear (721), and when it is in the first gear, shifts up to the second gear (722), and then (70).
Proceed to 9). When the gear position is not the first gear, it is determined whether the gear position of the four-speed automatic transmission 10 is the second gear (723);
When in 2nd gear, shift up to 3rd gear (724),
After that, proceed to (709). When not at second speed,
It is determined whether the gear stage of the 4-speed automatic transmission 10 is the third gear (725), and if it is not the third gear, the process proceeds to (709), and if it is the third gear, the fourth gear (overdrive) is selected.
Shift up (726) and then (709)
Proceed to. FIG. 8 is a hydraulic circuit diagram of a transfer control device according to a second embodiment of the vehicle transmission control device of the present invention. (Hereinafter, the same numbers as in the first embodiment indicate the same functional parts.) In this embodiment, when the spool 441 is set upward in the figure, the inhibitor valve 440 is
51 communicates with the drain port 458A via the oil port 443 of the sleeve-shaped land 445. The automatic transfer control mechanism 500 includes an actual vehicle speed sensor 602, a shift lever position sensor 603 that detects the set position of the shift lever 401, and a throttle opening sensor 6 that detects the throttle opening.
04. A first output shaft transmission torque sensor 607 and a second output shaft 52 that detect the transmission torque (t1) of the first output shaft 42 as means for detecting wheel slippage.
A second output shaft transmission torque sensor 608 that detects the transmission torque (t2) of, these outputs are input,
Output shaft rotation speed sensor 601 of transfer 40
electronic control device 60 that converts the output from
0, a throttle 511 provided in the oil passage 1M communicating with the oil passage 1, and an electromagnetic solenoid valve S4 that is turned ON and OFF by the output of the electronic control device 600, and the solenoid valve S4 is configured so that the vehicle speed is set to a set value. (For example, when the speed is over 20 km/h or when the drive wheel is idling, it is turned OFF and the line pressure of oil line 1 is generated in oil passage 1M. When the pressure is below the set value and the drive wheel is in a normal driving state, it is turned OFF.) and oil line 1
Discharge the hydraulic pressure of M. As a result, oil pressure related to the vehicle speed and the driving state of the drive wheels is generated in the oil path 1M. ON/OFF of the solenoid valve S4
Since the set value can be easily changed by the electronic control device 600 that controls the solenoid valve S4, it is easy for the driver to change it according to the driving conditions of the vehicle such as the road condition. The operation of the transfer 40 of this embodiment in each setting range will be explained as being different from that of the first embodiment. When the transfer manual valve 410 is set to the L4 position while the vehicle speed is below the set value and the drive wheels are in a normal driving state and the solenoid valve S4 is turned on, or when the vehicle speed becomes above the set value or when the vehicle is driven. When the wheels are idling and the solenoid valve S4 is OFF, the transfer manual valve 410 is in the L4 position and the vehicle speed goes from above the set value to below the set value, or when the drive wheels are in a normal driving state and the solenoid valve S is turned off.
4 is turned on from OFF, the pressure in the oil passage 1M is exhausted, so the spool 441 is set upward in the figure by the action of the spring 450, and as a result, the oil passage 1 and the oil passage 1N communicate with each other, and the hydraulic servo B-4 Hydraulic oil is supplied to the clutch C3, the oil passage 1P is connected to the drain port 457, and the pressure is discharged, and the hydraulic pressure of the hydraulic servo C-3 of the clutch C3 is discharged. This allows transfer 4
0 is a low-speed four-wheel drive state. After entering the low-speed four-wheel drive state, when the vehicle speed exceeds the set value or the drive wheels are in a idling state and the solenoid valve S4 is turned OFF, the line pressure of the oil passage 1M changes to the inhibitor valve 4.
40 oil chambers 455. Therefore, the spool 441 is set downward in the drawing, and the transfer gear 40 becomes H4 (four-wheel drive directly connected state). FIG. 9 is a block diagram of electronic control of a second embodiment of the control device for a vehicle transmission according to the present invention. In this embodiment, a first output shaft transmission torque sensor 607 that detects the transmission torque (t1) of the first output shaft 42 and a second
The second one detects the transmission torque (t2) of the output shaft 52.
An output shaft transmission torque sensor 608 and a transfer shift position sensor 609 for detecting the shift lever setting position of the shift lever 40 of the transfer shaft 40 are provided. Next, a second embodiment of a control device for a vehicle transmission according to the present invention will be described based on the flowcharts shown in FIGS. 10 and 11. Turn on the starter key, start engine E 801, output shaft rotation speed (N) from output shaft rotation speed center 601, and shift lever position sensor 6.
Shift lever setting position (SP) from 03, throttle opening (θ) from throttle opening sensor 604,
The transmission torque (t1) of the first output shaft 42 is determined by the first output shaft transmission torque sensor 607, the transmission torque (t2) of the second output shaft 52 is determined by the second output shaft transmission torque sensor 608, and the transmission torque (t2) of the second output shaft 52 is determined by the transfer shift position sensor 609. Transfer lever 40 shift lever 4
01 setting position (802), the shift lever setting position (SP) is set to P (parking) range, R
(Reverse) range or N (Neutral) range is determined 803, and when it is P range, R range or N range, solenoid valves S1 to S4 are activated.
It is set to OFF (804) and then returns to (802). When it is not in the P range, R range or N range, shift control of the 4-speed automatic transmission 10 is performed (805), and then solenoid valve S3 is turned on or off.
Performs lockup control to turn off (806),
Next, transfer control is performed (807), and the process returns to (802). As shown in the subroutine of FIG. 11, the transfer control (807) judges whether the solenoid valve S4 of the automatic transfer control mechanism 500 is ON or not (811), and when it is ON, the 4-wheel drive direct connection state H4 is established.
The vehicle speed (V) is stored in the ROM in advance.
It is determined whether the speed is higher than the vehicle speed (V2) when changing from the wheel drive deceleration state L4 to the four-wheel drive direct connection state H4 (81
2) When (V)>(V2), solenoid valve S4 is
The transfer is set to OFF to put the transfer 40 in the four-wheel drive direct connection state H4 (813), and then the process proceeds to (806). At (811), solenoid valve S4 is turned ON.
If not, the vehicle speed is higher than the set value, so the vehicle speed (V)
4-wheel drive direct connection state H that is stored in the ROM in advance
4 to 4-wheel drive deceleration state L4 (V
1) Determine whether it is higher than (814), (V)>(V
At the time of 1), proceed to (813), and when (V)>(V1) is not satisfied, and when (V)>V2 is not satisfied at (812), |1st output shaft transmission torque (t ₁ ) - 2nd output shaft It is determined whether the transmission torque (t2) | is greater than or equal to the set transmission torque difference (t) stored in advance in the ROM (815), and when |t1-t2|≧t, it is determined that the drive wheels are in a idling state. , proceed to 813, |t1-t2
| When not ≧t, it is determined that the driving wheels are in a normal driving state, solenoid valve S4 is set to ON, transferor 40 is set to four-wheel drive deceleration state L4, and (81
6), then proceed to (806).

[Brief explanation of the drawing]

Figure 1 is a schematic diagram of an automatic transmission for four-wheel drive, Figure 2
The figure is a schematic diagram of the gear train, FIG. 3 is a hydraulic circuit diagram of a four-speed automatic transmission according to the first embodiment of the vehicle transmission control system of the present invention, and FIG. 4 is a diagram of the vehicle transmission of the present invention. 4 of the first embodiment in the control device of
Cross-sectional view and hydraulic circuit diagram of wheel drive transfer,
FIG. 5 is a block diagram of a first embodiment of an electronic control device in a control device for a vehicle transmission according to the present invention, and FIG.
A first flowchart of the electronic control device of the embodiment,
FIG. 7 is a second flowchart of the electronic control device of the first embodiment of the vehicle transmission control device of the present invention, and FIG. 8 is a second flowchart of the electronic control device of the first embodiment of the vehicle transmission control device of the present invention. A hydraulic circuit diagram of a transfer control device, FIG. 9 is a block diagram of an electronic control device of a second embodiment of a control device for a vehicle transmission according to the present invention, and FIG. 10 is a diagram showing a control device for a vehicle transmission according to the present invention. FIG. 11 is a first flowchart of the electronic control device of the second embodiment of the vehicle transmission control device of the present invention. In the figure, B4...brake which is a frictional engagement element;
C3...Clutch which is a frictional engagement element, C4...
Clutch, which is a frictional engagement element, 1... line pressure oil path, 32... input shaft of four-wheel drive transfer,
42...First output shaft, 52...Second output shaft, Pf
... Planetary gear set, 600 ... Electronic control device, 601 ... Output shaft rotational speed sensor, 602
... Actual vehicle speed sensor, 603 ... Shift lever position sensor, 604 ... Throttle opening sensor, 607 ... First output shaft transmission torque sensor, 6
08...Second output transmission torque sensor, 609...
Transfer shift lever position sensor.

Claims (1)

[Claims] 1. A sensor that detects the output shaft rotation speed of a transmission;
a driving condition detecting means for detecting vehicle driving conditions, including a sensor for detecting the actual vehicle speed; a means for setting a gear position corresponding to the vehicle driving condition detected by the driving condition detecting means; and a set gear position. A transmission that changes gears based on a detected output shaft rotation speed, and a drive wheel is in a idling state when a difference between the vehicle speed and the detected actual vehicle speed is larger than a predetermined value. Control of an automatic transmission for a vehicle, characterized in that it has a slipping state detection means for determining that the drive wheels are slipping, and a means for switching the setting to a gear position higher than the current gear position when it is determined that the drive wheels are in the slipping state. Device. 2. A first torque detection means for detecting the transmitted torque of the first output shaft that drives either the front wheels or the rear wheels of the vehicle; a driving condition detecting means for detecting a vehicle driving condition, comprising a second torque detecting means for detecting transmission torque; a means for setting a gear position corresponding to the vehicle driving condition detected by the driving condition detecting means; A transmission that changes gears according to a set gear position, and a drive wheel that is in an idling state when the difference between the detected transmission torque of the first output shaft and the transmission torque of the second output shaft is greater than or equal to a predetermined value. Control of an automatic transmission for a vehicle, characterized in that it has a slipping state detection means for determining that the drive wheels are slipping, and a means for switching the setting to a gear position higher than the current gear position when it is determined that the drive wheels are in the slipping state. Device.