JPH04244667A - Controller for automatic transmission - Google Patents

Abstract

PURPOSE:To prevent a misshift preventive mechanism from operating inadvertently after detecting the transfer of a shift range in addition to car speed. CONSTITUTION:When car speed is judged to be more than the specified value by a car speed judging means 49 in a moment that a manual valve in a hydraulic control circuit 60, controlling the supply and discharge of working hydraulic pressure to a hydraulic actuator of a frictional clamping element, has judged a reverse range, a control part 47 controls three solenoid valves 66, 67, 68 so as to check any achievement of a reverse stage. In addition, this control part 47 prohibits the execution of reverse checking by these solenoid valves 66, 67, 68 till a range is a forward range and the car speed judging means 49 judges a high car speed after this means 49 judges a low car speed. Moreover, the control part 47 also prohibits the execution of the reverse checking till the forward range is judged after the reverse range is judged.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an automatic transmission, and more particularly to a control device for an automatic transmission having a mechanism for preventing a reverse misshift of a shift lever.

0002

2. Description of the Related Art In automatic transmissions installed in vehicles, shift valves that selectively operate friction engagement elements such as clutches and brakes are driven by solenoid valves to control gear shifts with high precision. In vehicles equipped with this type of automatic transmission control device, in order to prevent negative effects on the transmission, it is necessary to accidentally shift the shift lever into reverse range when the vehicle is traveling at a high speed higher than a specified speed. Some automatic transmissions have a reverse miss shift prevention mechanism that prevents the reverse range from being achieved by controlling a solenoid so as not to supply hydraulic pressure to the clutch involved in the reverse engagement of the automatic transmission even if the automatic transmission is operated.

0003

[Problems to be Solved by the Invention] However, in the conventional example described above, for example, when the vehicle speed is detected by counting pulses with a vehicle speed sensor or an engine rotation speed sensor, it is not possible to determine that the vehicle is at a predetermined speed or higher. However, it is not possible to determine whether the vehicle is moving forward or backward, so when the vehicle speed is increased in reverse range and the vehicle reaches a predetermined speed or higher, the achievement of reverse range is prevented, and reverse driving is prevented. There is a problem that it becomes impossible to continue.

[0004] Also, while driving at high speed in reverse range,
There is a problem in that even if the shift lever is shifted to neutral once and then shifted to reverse range again before the vehicle speed drops below a predetermined speed, the reverse miss shift prevention mechanism will be activated and the achievement of reverse range will be prevented. be.

[0005]

[Means for Solving the Problems] The present invention has been made for the purpose of solving the above-mentioned problems, and has the following configuration as a means for solving the above-mentioned problems. That is, a speed change gear mechanism, a plurality of friction engagement elements that switch the power transmission path of the speed change gear mechanism, a hydraulic control means that controls the supply and discharge of working hydraulic pressure to and from a hydraulic actuator of the friction engagement elements, and the a shift control means for switching the engagement state of a specific friction engagement element among the plurality of friction engagement elements; a vehicle speed determination means for determining the vehicle speed; and when the vehicle speed determined by the vehicle speed determination means is equal to or higher than a predetermined value, the shift A control device for an automatic transmission, comprising: a reverse prevention means for controlling the control means to prevent the attainment of a reverse gear; a range determination means for determining a range of a manual valve in the hydraulic control means; and control means for controlling the reverse prevention means to execute reverse prevention when the vehicle speed determined by the vehicle speed determination means is equal to or higher than a predetermined value at the moment when the determination means determines the reverse range.

Preferably, after the vehicle speed determining means determines a low vehicle speed, the range determining means determines that the vehicle is in a forward range, and the control means prevents the reverse inhibiting means from reversing until the vehicle speed determining means determines a high vehicle speed. Prohibits execution of interdiction. Preferably, the control means prohibits the reverse prevention means from performing reverse prevention after the range determination means determines the reverse range until the range determination means determines the forward range.

[0007]

[Operation] In the above configuration, when the vehicle speed at the moment when the reverse range is entered is above a predetermined value, reverse is prevented,
When the vehicle speed increases in reverse range, it functions so as not to prevent execution of reverse gear.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. <First Embodiment> FIG. 2 shows the mechanical configuration of an automatic transmission control device according to this embodiment. In the figure, an automatic transmission 10 includes a torque converter 20 as a main component.
, a speed change gear mechanism 30 driven by the output of the torque converter 20, a plurality of friction engagement elements 41 to 46 such as clutches and brakes that switch the power transmission path of the speed change gear mechanism 30, and one-way clutches 51 and 52. By tightening and releasing these, D as a driving range
, 2, 1, and R ranges, and 1st to 4th speeds in D range, 2
1st to 3rd speeds in the range and 1st to 2nd speeds in the 1st range can be obtained.

The torque converter 20 includes a pump 22 fixedly installed in a case 21 connected to the engine output shaft 1, and a turbine 23 arranged opposite to the pump 22 and driven by the pump 22 via hydraulic oil. , turbine 23
and the pump 22, and the transmission case 11
A stator 25 is supported by a one-way clutch 24 to increase torque, and a lock-up clutch is provided between the case 21 and the turbine 23 and directly connects the engine output shaft 1 and the turbine 23 via the case 21. It consists of 26. The rotation of the turbine 23 is outputted to the transmission gear mechanism 30 via the turbine shaft 27.

Here, a pump shaft 12 passing through a turbine shaft 27 is connected to the engine output shaft 1, and the pump shaft 12 drives an oil pump 13 provided at the rear end of the automatic transmission 10. It's becoming like that. On the other hand, the speed change gear mechanism 30 is composed of a Ravigneaux-type planetary gear device, and includes a small diameter small sun gear 31 loosely fitted on the turbine shaft 27 and a turbine shaft 2 behind the small sun gear 31.
A large sun gear 32 with a large diameter is loosely fitted onto the top of the shaft 7, a plurality of short pinion gears 33 are meshed with the small sun gear 31, the front half is meshed with the short pinion gear 33, and the rear half is meshed with the large sun gear 32. It is composed of a long pinion gear 34 that is meshed with each other, a carrier 35 that rotatably supports the long pinion gear 34 and the short pinion gear 33, and a ring gear 36 that is meshed with the front half of the long pinion gear 34.

A forward clutch 41 and a first one-way clutch 51 are interposed in series between the turbine shaft 27 and the small sun gear 31, and a coast clutch 42 is connected in parallel to these clutches 41, 51.
is interposed. Further, a 3-4 clutch 43 is interposed between the turbine shaft 27 and the carrier 35, and a reverse clutch 44 is interposed between the turbine shaft 27 and the large sun gear 32. Further, a 2-4 brake 45 serving as a band brake for fixing the large sun gear 32 is provided between the large sun gear 32 and the reverse clutch 44.
5 and the transmission case 11, a second one-way clutch 52 that receives the reaction force of the carrier 35 and a low reverse brake 46 that fixes the carrier 35 are provided in parallel. Then, the ring gear 36 is connected to the output gear 14.
The rotation is transmitted from the output gear 14 to left and right wheels (not shown) via a differential device.

Since the relationship between the operating states of the friction engagement elements 41 to 46 such as the clutches and brakes, and the one-way clutches 51 and 52 and the gears is well known, a detailed explanation thereof will be omitted here. Next, a hydraulic control circuit 60 for supplying and discharging hydraulic pressure to and from the actuators of each of the frictional engagement elements 41 to 46 will be explained with reference to FIG. Here, among the actuators, the hydraulic actuator 45' of the 2-4 brake 45 is constituted by a servo piston having an apply port 45a' and a release port 45b', and hydraulic pressure is supplied only to the apply port 45a'. When the hydraulic pressure is supplied to both ports 45a' and 45b', the 2-4 brake 45 is engaged, and when hydraulic pressure is supplied to both ports 45a' and 45b', the 2-4 brake 45 is engaged. 45. In addition, other frictional fastening elements 41
The actuators 44 and 46 are constituted by ordinary hydraulic pistons, and are adapted to engage the friction engagement elements when hydraulic pressure is supplied thereto.

The hydraulic control circuit 60 includes, as main components, a regulator valve 61 that adjusts the pressure of hydraulic oil discharged from the oil pump 13 to the main line 110 to a predetermined line pressure, and a manual A manual valve 62 that selects a range by operation, and friction engagement elements (actuators) 41 to 41 that operate according to the gear position.
1-2, 2-3, 3-4 supply and discharge hydraulic pressure to 46
shift valves 63, 64, and 65.

The manual valve 62 has an input port e into which line pressure is introduced from the main line 110, and first to fourth output ports a to d, and when the spool 62a moves, the input port e The D range and 2 range are connected to the first and second output ports a and b, the 1 range is connected to the first and third output ports a and c, and the R range is connected to the fourth output port d. It's getting old. First to fourth output lines 111 to 114 are connected to each of the output ports a to d, respectively.

Furthermore, the 1-2, 2-3, 3-4 shift valves 63, 64, and 65 have spools 63a and 65, respectively.
The spools 64a, 65a are biased to the right side in the drawing by springs (not shown), and pilot ports 63b, 64b, 65b are provided on the right side of these spools 63a, 64a, 65a. A pilot line 115 branched from the main line 110 via a line 118 is connected to the pilot port 63b of the 1-2 shift valve 63.
-3 The pilot port 64b of the shift valve 64 has a
A pilot line 116 branched from the first output line 111 is connected, and the pilot port 65b of the 3-4 shift valve 65 is connected to the main line 110.
1-2, 2-3, and 3-4 solenoid valves 66, 67, and 68 are attached to these pilot lines 115, 116, and 117, respectively. . These solenoid valves 66 to 68 drain the pilot lines 115, 116, and 117 when they are in the ON state, thereby discharging the pilot pressure in the pilot ports 63b to 65b of the corresponding shift valves 63 to 65. As a result, while the spools 63a to 65a are positioned on the right side in the drawing, pilot pressure is introduced from each pilot line 115, 116, 117 to the pilot ports 63b to 65b when each is in the OFF state, and the spools 63a to 65a are positioned on the right side in the drawing. 65a are respectively positioned on the left side.

[0016] Here, these solenoid valves 66~
The spools 63a to 68 of the shift valves 63 to 65 are turned on and off based on a map preset according to the vehicle speed and the throttle opening of the engine by signals from the control circuit. By switching the position of 65a, the oil passages leading to each of the frictional engagement elements 41 to 46 are switched. As a result, these frictional fastening elements 41 to 4
6 are engaged in a predetermined combination, and the gear position is thus changed according to the operating condition. In that case, ON/OFF of each gear stage and each solenoid valve 66 to 68
The relationship with the combination pattern is set as shown in FIG. 4, and when the 3-2 downshift is performed, the intermediate pattern shown in the figure is used.

On the other hand, among the first to fourth output lines 111 to 114 connected to each output port a to d of the manual valve 62, one line is connected to the main line 110 in each forward range of D, 2, and 1. A line 119 is branched off from the first output line 111 and serves as a forward clutch line, which is led to the forward clutch 41 via the one-way orifice 71. Therefore, in the D, 2, 1 range, the forward clutch 41 is always engaged. Here, an N-D accumulator 72 is connected to the forward clutch line 119 through a line 120, which acts as a buffer when the forward clutch is engaged. Reference numeral 73 is a one-way orifice.

The first output line 111 is led to the 1-2 shift valve 63, and when the 1-2 solenoid valve 66 is turned on and the spool 63a is positioned to the right, the servo apply line 121 is guided to the 1-2 shift valve 63. The servo piston 4 communicates with the servo piston 4 through a one-way orifice 74.
5' to the apply port 45a'. Therefore, D,2
, when the 1-2 solenoid valve 66 is in the ON state in the D range, 2nd, 3rd, and 4th speeds in the D range, 2nd and 3rd speeds in the 2nd range, and 2nd speed in the 1st range. When hydraulic pressure (i.e., servo apply pressure) is introduced into the release port 45b' (i.e., 2nd and 4th gears in D range, 2nd gear in 2nd range, and 2nd speed of 1st range)
-4 Brake 45 is engaged. The apply port 45a' is connected via a line 122 to a 1-2 accumulator 7 which acts as a buffer when the 2-4 brake is engaged.
5 is connected.

Furthermore, the first output line 111 is 3-4
Guided to shift valve 65, 3-4 solenoid valve 6
8 is in the OFF state and the spool 65a is located on the left side, it communicates with the line 123. Line 123 is led to 2-3 shift valve 64 and 2-3 solenoid valve 67
is in the ON state and the spool 64a is located on the right side, it communicates with the coast clutch line 124. The coast clutch line 124 reaches the coast clutch 42 via a one-way orifice 76 and a ball valve 77 for switching oil passages. Therefore, when the 2-3 solenoid valve 67 is in the ON state in the 2 and 1 range and the 3-4 solenoid valve 68 is in the OFF state, that is, in the 2nd speed of the 2nd range and the 1st and 2nd speeds of the 1st range. Coast clutch 42 is engaged.

[0020] Furthermore, main line 11 in the D, 2 range.
A second output line 112 that communicates with 0 is led to a 2-3 shift valve 64. And the second output line 11
2 communicates with the 3-4 clutch line 125 when the 2-3 solenoid valve 67 is in the OFF state and the spool 64a is located on the left side.
is connected to the 3-4 clutch 43 via a one-way orifice 78. Therefore, when the 2-3 solenoid valve 67 is in the OFF state in the D and 2 ranges, that is, the 3-4 clutch 43 is engaged in the 3rd and 4th speeds of the D range and the 3rd speed of the 2 range. Furthermore, this 3-4 clutch line 1
A 2-3 accumulator 79 is connected to 25, which acts as a buffer when the 3-4 clutch is operated. code 8
0 is a one-way orifice.

Here, the 3-4 clutch line 123
A line 126 branched from the 3-4 shift valve 6
When the 3-4 solenoid valve 68 is in the OFF state (that is, the spool 65a is located on the left side), the 2-3 timing valve 102 is connected to the line 127.
The servo release line 128 is connected to the servo release line 128 via the servo release line 128. This servo release line 128 reaches the release port 45b' of the servo piston 45' via the one-way orifice 81. Therefore, 2-3 in D,2 range
, and 3-4 solenoid valves 67 and 68 are both OFF.
3rd gear in D range and 3rd gear in 2nd range.
At this speed, servo release pressure is introduced into the release port 45b' of the servo piston 45', and the 2-4 brake 45 is released.

Furthermore, the servo release line 1
A line 129 branched from 28 connects to the coast clutch line 124 via the coast timing valve 82 and the ball valve 77, and connects the coast clutch 42 to the coast clutch line 124.
It has reached this point. Therefore, in the 3rd gear of the D range where hydraulic pressure is introduced into the servo release line 128, and in the 3rd gear of the 2nd range.
Even at high speeds, the coast clutch 42 is engaged.

A third output line 113 is connected to the main line 110 in one range by the manual valve 62.
1 through a ball valve 83 that acts as a switching valve.
-2 shift valve 63, and when the 1-2 solenoid valve 66 is in the OFF state and the spool 63a is located on the left side, it is connected to the low reverse brake line 130, and passes through the one-way orifice 84 that acts as an orifice for the accumulator. The brake 46 is reached. Therefore, 1-2 solenoid valves 66 in 1 range
When is in the OFF state, that is, in the first gear of the first range, the low reverse brake 46 is engaged. That is, in this embodiment, the third output line 113 connects to the manual valve 62.
It is supposed to form a low-speed range circuit.

In this embodiment, the low reverse brake line 130 has the one-way orifice 8.
A bypass circuit 131 is provided to bypass 4. This bypass circuit 131 branches from the upstream side of the one-way orifice 84 and is connected to the 3-4 shift valve 6.
5 and the 3-4 shift valve 6
5 to the downstream side of the one-way orifice 84, and when the 3-4 solenoid valve 68 is in the OFF state and the spool 65a is located on the left side, the Branch road 131a, 1
31b is communicated.

[0025] Furthermore, the low reverse brake line 13
0 is connected to an N-R accumulator 85 that acts as a buffer when the low reverse brake is activated. Reference numeral 96 is a one-way orifice. A fourth output line 114 communicating with the main line 110 in the R range of the manual valve 62 is connected to the ball valve 8 through a line 132 branched from the fourth output line 114.
On the other hand, the reverse clutch line 133 is connected to the reverse clutch 44. Therefore,
In the R range, the low reverse brake 46 is engaged only when the 1-2 solenoid valve 66 is in the OFF state, and the reverse clutch 44 is always engaged. That is, in this embodiment, the fourth output line 11
4, and a line 13 branched from the fourth output line 114
2 constitutes a reverse range circuit in the manual valve 62.

The hydraulic control circuit 60 also includes a lock-up shift valve 8 for actuating the lock-up clutch 26 in the torque converter 20 shown in FIG.
6, and a lockup controller valve 87 for regulating the hydraulic pressure supplied into the torque converter 20 via the lockup shift valve 86. The reference numeral 88 is a duty solenoid valve, and the reference numeral 89 is a lock-up solenoid valve.

The lock-up shift valve 86 includes:
Regulator valve 61 to torque converter line 1
A line 136 branched from the main line 110 and branched from a pilot line 135 equipped with a pressure reducing valve 90 is connected to the first and second pilot ports 92b and 92c provided at both ends. ，
137 are connected to each other. And line 13
6 is attached with the lock-up solenoid valve 89, and when the lock-up solenoid valve 89 is in the ON state, the spool 86a of the lock-up shift valve 86 is located on the right side, so that the torque converter line 134 is , to a torque converter line 138 leading into torque converter 20, thereby increasing the internal pressure of torque converter 20 and engaging lockup clutch 26. Further, when the lock-up solenoid valve 89 is turned OFF and the spool 86a of the lock-up shift valve 86 moves to the left, the torque converter line 134 communicates with the lock-up release line 139, and the lock-up in the torque converter 20 is released. Pressure is introduced to release the lockup clutch 26. Here, code 94
is the converter relief valve.

In addition to the above configuration, the hydraulic control circuit 60 of this embodiment includes the coast timing valve 82, which is used to adjust the timing of supplying and discharging hydraulic pressure during each gear shift.
In addition to the 2-3 timing valve 102, a bypass valve 101 and a 3-2 timing valve 103 are provided. As described above, the coast timing valve 82 is provided on the line 129 that branches off from the servo release line 128 and leads to the coast clutch line 124 via the ball valve 77, and on the line 129 that branches off from the servo apply line 121. 140, the servo apply pressure is guided to one end of the spool 82a. Then, the spool 8 is connected to the line 129.
When the servo release pressure introduced to the other end of 2a and the biasing force of the spring overcome the servo apply pressure, the line 129 is brought into communication. Therefore, the coast clutch pressure is supplied to the coast clutch 42 through this line 129 in the D range, and in the 2nd range of the 2nd range.
- During the 3rd shift up, the coast clutch 42 is engaged after the servo release pressure has risen sufficiently (that is, after the 2-4 brake 45 has been reliably released), and the 2-4 brake 45 and coast clutch 42 are engaged. clutch 4
This prevents double locking caused by the two being in the fastened state at the same time. Incidentally, since the servo apply pressure is guided to one end of the spool 82a of the coast timing valve 82, the timing at which the line 129 is communicated is changed according to the servo apply pressure, and the communication timing and servo release pressure are The correspondence relationship with the pressure level will be set appropriately.

[0029] Furthermore, the bypass valve 101 has a 3-
The hydraulic pressure (i.e., 3-4 clutch pressure) downstream of the one-way orifice 78 of the 3-4 clutch line 125 is Slot modulator pressure is led from the regulator valve 61 to one end of the spool 101a and is controlled by a pressure regulating valve 91 that acts to generate a pressure corresponding to the engine load through a line 142 to the spool 101a. The bypass lines 141 are respectively introduced at the other ends, and the bypass line 141 is cut off when the 3-4 clutch pressure rises above a predetermined value and the spool 101a moves to the left. Therefore, the 3-4 clutch pressure is
At the start of supply, the bypass line 141 supplies the gear quickly, but after that, the one-way orifice 78 slows down the supply.
The timing of the fastening will be adjusted. In addition, code 9
2 is a duty solenoid valve, and 93 is an accumulator.

Furthermore, the 2-3 timing valve 10
2 is a line 12 led from the 3-4 shift valve 65
7 and the servo release line 128, and the hydraulic pressure in the 3-4 clutch line 125 (i.e., 3-4 clutch pressure) is provided at one end side of the spool 102a.
However, servo release pressure is introduced at the other end. Then, due to the action of the 3-4 clutch pressure and the servo release pressure, the servo release line 1
28 is connected to the line 127 or drained to adjust the servo release pressure in accordance with the 3-4 clutch pressure.

[0031] Also, the 3-2 timing valve 103
a first bypass line 143 that bypasses the one-way orifice 74 on the servo apply line 121;
a second bypass line 1 that bypasses the one-way orifice 71 in the forward clutch line 119;
44. A pilot line 145 branched from a line 118 leading to the main line 110 is connected to one end of the spool 103a of the 3-2 timing valve 103.
A drain line 146 branched from the servo release line 128 is connected to the intermediate portion of a, and a 3-2 solenoid valve 9 is connected to the pilot line 145.
5 is attached. This 3-2 timing valve 10
3, by the operation of the 3-2 solenoid valve 95,
The first and second bypass lines 143 and 144 are opened and closed during 1-2 upshifting, 3-2 downshifting, and 4-2 downshifting to reduce the hydraulic pressure during these downshifts. Control supply/discharge timing. That is, at the time of 1-2 shift up, the first bypass line 143 is first communicated, and the servo apply pressure is promptly supplied to the apply port 45a' of the servo piston 45'. When the first bypass line 143
By shutting off the servo apply pressure, the servo apply pressure is gradually supplied to the apply port 45a' of the servo piston 45' through the one-way orifice 74 in the latter half of the speed change operation.

Furthermore, during a 3-2 downshift, the drain line 146 is first communicated with the drain port at the start of the shift, and then the drain line 146 is shut off. Therefore, the servo release pressure is quickly discharged through the drain line 146 during the first half of the gear shift operation, and is slowly discharged during the second half through the one-way orifice 81 that performs a throttling action in the discharge direction on the servo release line 128. becomes. Furthermore, during a 4-2 downshift, first the second bypass line 1 is
44 is opened to quickly supply forward clutch pressure to the forward clutch 41, and in the latter half of the gear shifting operation, the second bypass line 144 is shut off, thereby reducing the forward clutch pressure by the throttling action of the one-way orifice 71. Forward clutch pressure is gently supplied to the word clutch 41.

As shown in FIG. 1, the hydraulic control circuit 60 configured as described above includes the 1-2, 2-3, and 3-4 solenoid valves 66, 67, A control section 47 for controlling the opening and closing of 68 is attached. This control unit 47, for example,
It consists of a microcomputer, and receives information from the gear position detection section 48 that detects the range signal of the manual valve 62 and the vehicle speed detection section 49 that detects the vehicle speed V, and performs the above-mentioned 1-2, 2-3, and issues opening/closing commands to the 3-4 solenoid valves 66, 67, and 68. In addition, in the case of this example, the above 1-2, 2-3, and 3
-4 solenoid valves 66, 67, 68 follow the solenoid pattern shown in FIG.

Next, a control procedure for the automatic transmission according to this embodiment will be explained. FIG. 6 is a flowchart showing a procedure for determining an incorrect shift of a shift lever related to a reverse range. In the figure, the control unit 47 initializes the misshift determination flag R, which will be described later, in step S1.
Set MISF to 0. In the following step S2, the vehicle speed VSP is detected based on the detection signal from the vehicle speed detector 49, and the current shift position is detected based on the range signal from the gear position detector 48. Then, in step S3, the flag RM
It is determined whether ISF is 1 or not, but if this is the first process, the determination is NO, so the process advances to step S4.

In step S4, it is determined whether the vehicle speed VSP is equal to or higher than the reference vehicle speed data VSS1 and has entered the reverse range for the first time during the current processing, that is, the current reverse range signal Ri is 1 and the reverse range signal Ri-1 from the previous processing is determined. Determine if is 0. The verdict here is Y
If it is ES, it becomes clear that the vehicle speed at the moment the shift lever is put into the reverse range is above a certain value, so the miss shift determination flag RMISF is set to 1 in step S5.
Make it.

On the other hand, if the determination at step S3 is YES, then at step S6 the vehicle speed VSP is changed to the reference vehicle speed data V.
It is determined whether the range is smaller than SS2 (however, VSS1≧VSS2) and the range is set to the forward range. In other words, it is determined whether any one of the N range signal, D range signal, S range signal, or L range signal is 1, or in other words, it is not in the reverse range state. If the determination result in step S6 is YES, it means that the vehicle has stopped once and the subsequent vehicle speed is below a certain value and is not in the reverse range state. Therefore, in the next step S7, the misshift determination flag RMISF is set to 0.
to cancel the misshift judgment.

In step S8, it is again determined whether the misshift determination flag RMISF is 1, and if the flag is 1, the process moves to step S9. In this step S9,
The control unit 47 uses 1-2, 2-3, and 3-4
A control signal is sent to solenoid valves 66, 67, and 68. As a result, the spool 6 of the 1-2 shift valve 63
3a is located on the right side, the fourth output line 114, line 1
32 and the reverse clutch pressure guided through the ball valve 83 is no longer supplied to the low reverse brake line 130, making it impossible to engage the low reverse brake 46. Therefore, even if the manual valve 62 is operated to the R range, reverse engagement of the automatic transmission is prohibited.

Thereafter, in step S10, it is determined whether this process is finished, and when the process is to be continued, the process returns to step S2. As described above, in this embodiment, if the vehicle speed when the shift lever is placed in the R range is equal to or higher than a predetermined value, it is determined that a misshift has occurred and reverse is prevented, thereby avoiding the danger of executing the reverse gear. effective. <Second Embodiment> A second embodiment of the present invention will be described below. Note that the hydraulic control circuit and mechanical configuration of the automatic transmission according to this embodiment are the same as those in the first embodiment, so their explanation will be omitted here.

FIG. 7 is a flowchart showing a procedure for determining an incorrect shift of the shift lever in the reverse range according to this embodiment. In the figure, the control unit 47 initializes the flags in step S11 by setting a miss shift determination flag RMISF and a forward travel determination flag TRMI, which will be described later.
Set SF to 0. In the following step S12, the current shift position is detected based on the vehicle speed VSP based on the detection signal from the vehicle speed detection section 49 and the range signal. Then, in step S3, it is determined whether the flag TRMISF is 1 or not. If this is the first processing, the determination is NO, so the process advances to step S14. In step S14, it is determined whether the vehicle is traveling forward with the vehicle speed VSP equal to or higher than the reference vehicle speed data VSS1. In other words, if any one of the D range signal, S range signal, or L range signal is 1
Determine whether or not, and if the determination result is YES,
Proceeding to step S15, the forward running determination flag TRMI is set.
Set SF to 1.

However, the determination result in step S13 is Y.
If ES, the vehicle speed VSP is smaller than the reference vehicle speed data VSS2 (VSS1≧VSS2) in the following step S16.
), and the range is set to other than the reverse range. In other words, N range signal, D range signal,
It is determined whether either the S range signal or the L range signal is 1, and if the determination result is YES, the flag TRMISF is set to 0 in the next step S17.
Make it. In other words, if the vehicle is traveling at low speed and the current range is other than the reverse range, the shift lever can be put into reverse.

[0041] In step S18, the flag RMISF is set to 1.
If the result is NO, step S
At step 19, it is determined whether the flag TRMISF is 1 and the reverse range has been reached for the first time during this processing. In other words,
It is determined whether the reverse range signal Ri during the current processing is 1 and the reverse range signal Ri-1 during the previous processing is 0. If the determination here is YES, it means that the shift lever was put into reverse while the vehicle was moving forward at high speed, so the program proceeds to step S20 and sets the misshift determination flag RMISF to 1.

On the other hand, flag R is determined in step S18.
MISF is 1, flag TRMIS is set in the next step S21
If F is 0, it is determined that a misshift occurred in the past but the vehicle is currently in a forward running state where the vehicle speed is below a certain value, so the flag RMISF is set to 0 in the subsequent step S22. In step S23, it is again determined whether the misshift determination flag RMISF is 1, and if the flag is 1, the process moves to step S24. In this step S24,
As in the first embodiment described above, the control unit 47 controls the opening and closing of predetermined solenoid valves using a solenoid pattern for dealing with misshifts in the reverse range, that is, a solenoid pattern for preventing misshifts.

In step S25, it is determined whether or not to end this process, and when it is determined to continue the process,
The process returns to step S12 again. As described above, in this embodiment, reverse prevention control is executed when the shift lever is put into reverse while the vehicle is in a high-speed forward traveling state, but after it is determined that the vehicle is traveling at a low speed, By prohibiting reverse prevention control until the high vehicle speed in the range is determined, there is an effect that reverse travel can be performed smoothly. <Modification> In the above embodiment, after a misshift is determined, for example, when the vehicle travels downhill in the N range, the misshift determination flag may be set to 0 if the vehicle speed is lower than a predetermined value. Specifically, step S2 in FIG.
1, instead of determining whether the forward travel flag TRMISF is 0 or not, the vehicle speed VSP is determined based on the vehicle speed data VSS3.
is smaller (however, VSS2>VSS3), and determines whether the range signal of the N range signal, D range signal, S range signal, or L range signal is 1,
If the determination result is YES, the flag RMISF may be set to 0 in the next step S22. <Third Embodiment> A third embodiment of the present invention will be described below. Note that the hydraulic control circuit and mechanical configuration of the automatic transmission according to this embodiment are the same as those in the first embodiment, so their explanation will be omitted here.

FIG. 8 is a flowchart showing a procedure for determining an incorrect shift of the shift lever in the reverse range according to this embodiment. In the same figure, the control unit 47 initializes the flags in step S31 by setting the miss shift determination flag RMISF and the shift lever from R range to N range to
R is a flag that determines whether the R range has been operated.
- Set the NR determination flag NRMISF to 0. In the following step S32, the vehicle speed VSP is detected based on the detection signal from the vehicle speed detection section 49, and the current shift position is detected based on the range signal.

In step S33, it is determined whether the range has shifted from a state other than the reverse range to the reverse range. In other words, the reverse range signal Ri during the current processing is 1, and the reverse range signal Ri during the previous processing is
Determine whether 1 is 0. If the determination here is YES, the R-NR determination flag NRMI is set in step S34.
It is determined whether SF is set, and if the flag is not 1, it is set to 1 in step S35. Continued step S36
It is determined whether the vehicle speed VSP is greater than the reference vehicle speed data VSS1. If the vehicle speed VSP is greater than the reference value, the flag RMISF is set to 1 in step S37, and if the vehicle speed VSP is less than the reference value, the flag RMISF is set to 0 in step S38.

On the other hand, if the determination in step S33 is NO, it is determined in step S40 whether the current range is in the reverse range state. If the determination here is NO, in step S41, the other current range signals are determined, that is, it is determined whether any one of the D range signal, S range signal, or L range signal is 1. Do this. If the result is NO, flag RMISF is set to 0 in step S42, but if the result is YES, flags RMISF and NRMIS are set to 0 in step S43.
Set both F to 0.

If the determination in step S40 is YES, it is determined in the next step S44 whether the flag RMISF is 1 and the vehicle speed VSP is greater than the reference vehicle speed data VSS1. If the result of this determination is YES, it is assumed that a misshift has occurred, and the flag RMISF is set in step S46.
is set to 1, but if the judgment result is NO, the flag RMIS
Set F to 0.

In step S47, it is determined whether or not the misshift determination flag RMISF is 1. If the flag is 1, the control section 47 performs the process of step S48, that is, as in the first embodiment described above, the control section 47 determines whether or not the misshift determination flag RMISF is 1. The opening and closing of predetermined solenoid valves is controlled to realize a solenoid pattern to prevent misshifts.

In step S49, it is determined whether or not to end this process, and when it is determined to continue the process,
The process returns to step S32 again. As described above, in this embodiment, it is possible to simplify the determination process by determining a misshift only from the range signal, and also to
This has the effect of allowing reverse driving to continue by prohibiting the execution of reverse prevention when an operation to shift into range and then return to R range is detected.

[0050] In the above first to third embodiments, 1-2
, 2-3, and 3-4 solenoid valves 66, 67, 6
Issue a predetermined pattern opening/closing command to 8, 1-2,
Reverse prevention control is performed by operating the 2-3 and 3-4 shift valves 63, 64, and 65, but a valve dedicated to reverse prevention control is provided in place of these, and the control unit 47 turns on the valve. /off control may be used to prevent the reverse range from being achieved.

[0051]

[Effects of the Invention] As explained above, according to the present invention,
By detecting the vehicle speed at the moment the vehicle enters the reverse range, or the increase in vehicle speed while in the reverse range, and controlling execution or prohibition of reverse prevention, the reverse prevention mechanism, which prevents misshifts, may be activated inadvertently. It has the effect of preventing

Furthermore, by detecting range switching, for example, the R range is shifted to the N range, and then the R range is shifted to the N range.
When the vehicle is returned to the range, it is possible to appropriately operate the misshift prevention mechanism based on the result of range switching, such as prohibiting the execution of reverse prevention and continuing reverse travel.

[Brief explanation of the drawing]

FIG. 1 is an enlarged view of a main part of a hydraulic control circuit in a control device for an automatic transmission according to an embodiment of the present invention.

FIG. 2 is a diagram showing the mechanical configuration of an automatic transmission according to an embodiment of the present invention.

FIG. 3 is a hydraulic control circuit in an automatic transmission control device according to an embodiment of the present invention.

FIG. 4 is a diagram showing the relationship between each gear stage and the ON/OFF combination pattern of each solenoid valve in the automatic transmission of the embodiment.

FIG. 5 is a diagram showing solenoid patterns of 1-2, 2-3, and 3-4 solenoid valves related to the automatic transmission of the embodiment.

FIG. 6 is a flowchart showing a procedure for determining an erroneous shift of the shift lever in the reverse range according to the first embodiment.

FIG. 7 is a flowchart showing a procedure for determining an erroneous shift of a shift lever in a reverse range according to a second embodiment.

FIG. 8 is a flowchart showing a procedure for determining an erroneous shift of a shift lever in a reverse range according to a third embodiment.

[Explanation of symbols]

10 Automatic transmission 26 Lockup clutch 30 Speed gear mechanism 41 Forward clutch 42 Coast Clutch 43 3-4 clutch 44 Reverse clutch 45 2-4 brake 46 Low reverse brake 200 Torque converter in 201 Torque converter out 202 Cooler

Claims (3)

[Claims] 1. A speed change gear mechanism, a plurality of friction engagement elements for switching a power transmission path of the speed change gear mechanism, a hydraulic control means for controlling supply and discharge of working hydraulic pressure to a hydraulic actuator of the friction engagement elements, and a predetermined A shift control means for switching the engagement state of a specific friction engagement element among the plurality of friction engagement elements during gear shifting, a vehicle speed determination means for determining vehicle speed, and when the vehicle speed determined by the vehicle speed determination means is equal to or higher than a predetermined value. , a control device for an automatic transmission, comprising: reverse prevention means for controlling the shift control means to prevent the achievement of a reverse gear; range determination means for determining a range of a manual valve in the hydraulic control means; , control means for controlling the reverse prevention means to execute reverse prevention when the vehicle speed determined by the vehicle speed determination means is equal to or higher than a predetermined value at the moment when the range determination means determines the reverse range. Transmission control device. 2. The control means controls the reverse prevention by the reverse prevention means until the range determination means determines that the vehicle is in the forward range and the vehicle speed determination means determines the high vehicle speed after the vehicle speed determination means determines the low vehicle speed. 2. The automatic transmission control device according to claim 1, wherein execution is prohibited. 3. The control means prohibits the reverse prevention means from performing reverse prevention after the range determination means determines the reverse range until the range determination means determines the forward range. The automatic transmission control device according to item 1.