JPH05272631A - Shift controller for automatic transmission - Google Patents

Abstract

PURPOSE:To ensure stable travel even when a failure occurring in a solenoid valve and a control system therefor, by providing a construction wherein an ordinary solenoid valve and an emergency valve make control of a shift valve for effecting speed change between a speed change stage rendering an engine brake effective and another speed change stage. CONSTITUTION:An emergency solenoid valve V5 is connected to a shift valve V4, and this emergency solenoid valve V5 is operated in accordance with the detection results of a failure detection means M1 and a shift detection means M2. Namely, when the failure detection means M1 detects a failure in another solenoid valve V3 and the shift detection means M2 detects that supply of oil pressure from the solenoid valve V3 to the shift valve V4 is stopped whereby a set speed change stage is selected, the oil pressure of an operating oil is supplied from the emergency solenoid valve V5 to the shift valve V4 by which the shift valve V4 is changed over. Accordingly, the operating condition established due to a failure of the solenoid valve V3 is solved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift control device for an automatic transmission, and more particularly to a shift control device for an automatic transmission which is constructed such that switching of a running range and shifting are performed by a solenoid valve which operates based on an electric signal. It is a thing.

[0002]

2. Description of the Related Art The selection of a running range and a gear change in an automatic transmission for a vehicle are performed by changing a friction engagement device to which hydraulic pressure is to be supplied. This can be performed by electrically controlling the solenoid valve and switching the predetermined valve. An example of this is as follows:
No. 310, already proposed. This is provided with a first and a second range switching valve operated by an on / off controlled solenoid valve to provide an R (reverse) range, N
(Neutral) and P (parking) range, D
It is configured to output hydraulic pressure for four ranges of (drive) range and E (engine brake) range, and for fail-safe, switches between the R range oil passage and the N (P) range oil passage, and also the D range. A switching valve for switching between the hydraulic pressure and the E range hydraulic pressure is provided. Also, this Japanese patent application 4-
The 54310 apparatus is provided with three shift valves to set four forward gears and one reverse gear.
Of these shift valves, the 2-3 shift valve that shifts between the 2nd speed and the 3rd speed is connected to the E range oil passage, and when the E range is selected, this 2 The hydraulic pressure is supplied to a predetermined friction engagement device that is engaged to apply the engine brake through the -3 shift valve.

[0003]

In the device proposed by the present applicant, each shift valve is also controlled by the solenoid valve, and the 2-3 shift valve is a signal supplied via a solenoid valve. The pressure is applied to one end side of the spool so as to attain the third speed and the fourth speed, and the signal pressure thereof is discharged to press the spool with a spring, for example, the first speed and the first speed. It is in a state of achieving 2nd speed. In such a configuration, 2-3
Since the operation of the shift valve is controlled by only one solenoid valve, for example, if the signal pressure remains supplied from the solenoid valve to the 2-3 shift valve,
Even if the E range is selected, the 2-3 shift valve does not switch to set the first speed or the second speed at which the engine brake works, so the engine brake cannot be applied.

In order to eliminate such inconvenience, it is possible to act on the 2-3 shift valve so that the hydraulic pressure generated when the E range is selected opposes the signal pressure.
In such a configuration, the spring force and the E range pressure oppose the signal pressure. Therefore, if the E range is selected, the 2-3 shift valve will be set to a state in which the gear stage in which the engine brake works is set. Change Therefore, even if the solenoid valve that controls the 2-3 shift valve fails, the engine brake can be activated by shifting to the gear position where the engine braking is effective. However, on the other hand, since the state in which the engine brake is applied is controlled by only one solenoid valve, if this solenoid valve fails with the E range selected, it becomes impossible to set another gear.

As described above, in the above device, when either the solenoid valve for switching the range or the solenoid valve for controlling the 2-3 shift valve fails,
There was a problem that the engine brake did not work or, on the contrary, the engine brake state could not be released.

The present invention has been made in view of the above-mentioned circumstances, and a solenoid valve for controlling a shift valve for performing a shift between a shift stage in which an engine brake is applied by an engine brake range hydraulic pressure and a shift stage other than the above is provided. It is an object of the present invention to provide a shift control device capable of achieving and releasing an engine braking state even if a failure occurs.

[0007]

The present invention achieves the above objects by being configured as shown in FIG. That is, the present invention is directed to a range switching valve V2 which is operated by a solenoid valve V1 to switch the supply state of hydraulic pressure so as to set a plurality of traveling ranges, and a gear shift which applies an engine brake by the hydraulic pressure generated when the engine brake range is selected. In a shift control device for an automatic transmission, which comprises a shift valve V4 which is switched by another solenoid valve V3 so as to carry out a shift between a shift stage and another shift stage, Fail detecting means M for detecting a fail
1 and shift detecting means M2 for detecting that the shift stage set by switching the shift valve V4 operating due to the failure of the other solenoid valve V3 to another state is selected. And the fail detecting means M1 detects the fail of the other solenoid valve V3 and the shift detecting means M2 detects that the shift stage set by switching the shift valve V4 is selected. An emergency solenoid valve V5 for supplying a hydraulic pressure for forcibly switching the shift valve V4 from a state set by the failure of the other solenoid valve V3 to another state without passing through the range switching valve V2. It is characterized by having and.

[0008]

In the shift control device of the present invention, the range switching valve V2 is operated by the solenoid valve V1 to switch to a plurality of traveling ranges including the engine braking range. In addition, the shift between the shift stage in which the engine brake is applied by the engine brake range hydraulic pressure and the shift stage other than that is performed by the other solenoid valve V3.
Is performed by switching the shift valve V4. An emergency solenoid valve V5 is connected to the shift valve V4, and the emergency solenoid valve V5 is connected to the fail detecting means M1 and the shift detecting means M2.
It is operated based on the detection result of. That is, the gear detection means M1 detects the failure of the other solenoid valve V3, and the shift detection means M2 releases the supply of the hydraulic pressure from the other solenoid valve V3 to the shift valve V4. When the selection is detected, the hydraulic pressure is sent from the emergency solenoid valve V5 to the shift valve V4 to switch the shift valve V4. Therefore, the state due to the failure of the other solenoid valve V3 is eliminated.

[0009]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 2 is a schematic block diagram showing an embodiment of the present invention, in which an automatic transmission A has a torque converter 2 having a lock-up clutch 1 and a set of planetary gear mechanisms as a speed change mechanism. A second speed change unit 3 and a first speed change unit 4 that sets a plurality of forward speeds and reverse speeds by two sets of planetary gear mechanisms are provided.

The second transmission section 3 is for performing two-stage switching between high and low, and the carrier 5 of the planetary gear mechanism thereof.
Is connected to the turbine runner 6 of the torque converter 2, and a clutch C0 and a one-way clutch Fo are provided between the carrier 5 and the sun gear 7 so as to be in parallel relationship with each other. H
A brake B0 is provided between it and u.

The sun gears 8 and 9 in each planetary gear mechanism of the first transmission section 4 are provided on a common sun gear shaft 10, and the left side (front side) of the first transmission section 4 in the drawing.
Ring gear 11 and second speed change portion 3 in the planetary gear mechanism of
A first clutch C1 is provided between the sun gear shaft 10 and the ring gear 12 of the second speed change portion 3, and a second clutch C2 is provided between the sun gear shaft 10 and the ring gear 12 of the second transmission portion 3. The carrier 13 of the planetary gear mechanism on the left side of the figure and the ring gear 14 of the planetary gear mechanism on the right side (rear side) in the first transmission portion 4 are integrally connected, and the output shaft is connected to these carrier 13 and ring gear 14. 15 are connected.

A first brake B1 which is a band brake is provided to stop the rotation of the sun gear shaft 10,
More specifically, it is provided on the outer peripheral side of the clutch drum of the second clutch C2, and the first one-way clutch F1 and the second brake B2 are arranged in series between the sun gear shaft 10 and the housing Hu. Further, the second one-way clutch F2 and the third brake B3 are arranged in parallel between the carrier 16 and the housing Hu in the planetary gear mechanism on the rear side.

The hydraulic control device 17, which supplies and discharges hydraulic pressure to and from the clutches C0, C1 and C2 and the brakes B0, B1, B2 and B3, mainly performs the first to fourth speed shifts. First and second solenoid valves S of
1, S2, a linear solenoid valve SLU for mainly controlling the lockup clutch 1, and third to fifth solenoid valves S3, S for switching the traveling range.
4 and S5. These solenoid valves S
Among the 1, S2, SLU, S3, S4, and S5, a shift electronic control unit (hereinafter, temporarily referred to as a shift ECU) for controlling the first and second solenoid valves S1 and S2 and the linear solenoid valve SLU. ) 18, and third to fifth solenoid valves S3 for switching the running range,
An electronic control unit (hereinafter, temporarily referred to as a range switching ECU) 19 for controlling a running range for controlling S4 and S5 is provided. Each of these EUCs 18 and 19 is mainly composed of a central processing element, a memory element, and an input / output interface, and the shift ECU 18 has a throttle opening signal, a vehicle speed signal, and a pattern select signal as in the conventional ECUs. Signals such as a signal, an engine water temperature signal, and a brake signal are input, and the shift ECU 18 calculates a shift stage to be set based on these input signals and a shift map stored in advance. Then, a signal is output to the first and second solenoid valves S1 and S2 so as to set the shift speed, and a signal is output to the linear solenoid valve SLU.

On the other hand, the range switching ECU 19 includes
Range selection switch 2 for selecting each of the parking (P) range, reverse (R) range, neutral (N) range, drive (D) range, S range, and L range
0 is connected, and the range switching ECU 19 sets the third to fifth solenoid valves S3, S4, S5 to set the travel range selected by the range selection switch 20.
Is controlled to be turned on / off, and at the same time, a range position signal is output to the speed change ECU 18 and a range indicator (not shown). Further, to the range switching ECU 19, a shift signal indicating a shift speed and a signal from a parking detection switch (not shown) are input from the shift ECU 18.

The hydraulic control device 17 is shown in FIGS.
The hydraulic circuit shown in FIG. It should be noted that the circled numbers in FIGS. 3 to 5 indicate that lines having the same numbers are connected to each other. As shown in FIG. 3, two range switching valves 200 and 300 and a switching valve 400 for switching the traveling range are provided.

The first range switching valve 200 is provided with a spool 201 having four lands and a spring 202 provided at one end portion (lower end portion in the figure) of the spool 201. A third solenoid valve S3 is connected to the control port 203 at the opposite end. This third solenoid valve S3 is used for the hydraulic pump 10
The line pressure PL obtained by adjusting the oil pressurized at 0 with the primary regulator valve 101 is used as the control port 203.
For supplying and discharging to the control port 203 and closing the drain port in the off state.
L is generated, and the drain port is opened in the ON state to exhaust the pressure from the control port 203. The first range switching valve 200 is provided with the spool 201 because the third solenoid valve S3 is in the ON state.
Is pushed by the spring 202 and is in the position shown in the right half of FIG. When the spool 201 is in the position shown in the left half of FIG. 3 against the elastic force of the spring 202 by communicating with the drain port 207 and by turning off the third solenoid valve S3, the input port 204 is opened. The first output port 205 is communicated with the drain port 208 at the same time as being communicated with the second output port 206.

The second range switching valve 300 has a spool 301 having six lands and a spring 302 arranged at one end of the spool 301, and is formed at the end opposite to the spring 302. The fourth solenoid valve S4 is connected to the control port 303.
The fourth solenoid valve S4 is for supplying / discharging the line pressure PL to the control port 303, and like the third solenoid valve S3 described above, the drain port is closed in the OFF state to close the line pressure to the control port 303. When PL is generated and the drain port is opened in the ON state, the pressure is exhausted from the control port 303. Further this second
The range switching valve 300 is the first range switching valve 20.
0, a first input port 304 connected to the first output port 205 and a second input port 305 connected to the second output port 206 of the first range switching valve 200, and a parking port 306,
D range port 307, engine brake port 30
8 and R range port 311 has four output ports.

Then, the second range switching valve 300
Means that when the spool 301 is in the position shown in the right half of FIG. 3 due to the fourth solenoid valve S4 being in the ON state, the first input port 304 and the parking port 30
6, second input port 305 and engine brake port 3
08, D range port 307 and drain port 309, R
The range port 311 and the drain port 312 are communicated with each other. When the spool 301 is in the position shown in the left half of FIG. 3 due to the fourth solenoid valve S4 being off, the first input port 304 and the D range port 307, the parking port 306 and the drain port 310, Engine brake port 308 and drain port 309, second input port 305 and R range port 311
And communicate with each other.

The D range oil passage 112 is connected to the D port 307 among the output ports of the second range switching valve 300. The D range oil passage 112 has two input ports and one output port. Check ball valve 10
4 is connected to one of the input ports. An engine brake range oil passage 113 is connected to the engine brake port 308, and the engine brake range oil passage 113 is connected to the check ball valve 104.
Is connected to the other input port of the check ball valve 104, and the output port of the check ball valve 104 is connected to the first clutch C1. Two remaining parking ports 30
6 and the R range port 311 are connected to the corresponding input ports in the switching valve 400.

This switching valve 400 is for inverting and connecting an oil passage on the output side to two predetermined input ports, and has a spool 401 having four lands.
Is pressed in the axial direction by a spring 402 arranged at one end thereof, and a fifth solenoid valve S5 is connected to a control port 403 formed at an end opposite to the spring 402. This fifth solenoid valve S
Numeral 5 is an emergency solenoid valve which is operated at the time of failure, and in the ON state, the drain port is closed and the control port 4
If the fifth solenoid valve S5 is in the ON state, the line pressure PL is generated in 03, and the drain port is opened in the OFF state to discharge the pressure from the control port 403.
The spool 401 is in the first state in which it is lowered to the position shown in the left half of FIG. 3, and vice versa.
Is off, the spool 401 is in the second state in which it is pushed up to the position shown in the right half of FIG.

The switching valve 400 is provided with first and second input ports 405 and 406 as input ports in order from the top on the left side of FIG.
05 is connected to the cranking port 306 of the second range switching valve 300, and the second input port 406 is connected to the R range port 311 of the second switching valve 300. Further, the switching valve 400 includes, as output ports, the first parking port 409, in order from the top on the right side of FIG.
Three ports, an R port 410 and a second parking port 411, are formed. The spool 401 is shown in FIG.
In the first state in which the position is lowered to the left half, the first input port 405 communicates with the first parking port 409 and the second input port 406 communicates with the R port 410. Further, when the spool 401 is pushed up to the position shown in the right half of FIG. 3, the first input port 405 communicates with the R port 410, and the second input port 406 moves to the second position.
It communicates with the parking port 411.

The R port 410 is connected to the R range oil passage 1.
10 is connected, and the parking range oil passage 111 is connected to the first and second parking ports 409 and 411. That is, the switching valve 400 connects the R-range oil passage 110 and the parking-range oil passage 111 to the R-range port 311 and the parking port 306 of the second range switching valve 300 as they are or by inverting them. It has become.

The R range oil passage 110 is connected to the third brake B3 via a check ball valve 103 having two input ports and one output port, and the R range oil passage 110 is , And is connected to one input port in another check ball valve 105 having two input ports and one output port shown in FIG.

Further, a 1-2 shift valve 500, a 2-3 shift valve 600, a 3-4 shift valve 700, and a cutoff valve 800 are provided. These valves are for executing the shift between the first speed to the fourth speed in the forward speed, and are basically configured in the same manner as the conventionally known ones.

That is, in the 1-2 shift valve 500, a spring 502 is arranged at one end of a spool 501 having four lands, and a hold port 503 is formed at the end where the spring 502 is arranged. Control port 50 at the end opposite to 503
4 is formed on the control port 504.
Solenoid valve S2 is connected. The second solenoid valve S2 is for supplying / discharging the line pressure PL from the line pressure oil passage 102, and in the ON state, the drain port is opened and discharged, and in the OFF state, the drain port is closed. -2 Control port 5 of shift valve 500
The line pressure PL is generated at 04.

The spool 501 of the 1-2 shift valve 500 is positioned as shown in the left half of FIG. 4 by the second solenoid valve S2 being turned on or the line pressure PL acting on the hold port 503. As a result, the first input port 505 communicates with the first brake port 506, and the second input port 50 connected to the output port of the check ball valve 104.
7 communicates with the second brake port 508, the third input port 509 is closed, and the third brake port 5
10 communicates with the drain port. Also hold port 5
03, and the second solenoid valve S2 is turned off, whereby the spool 501 of the 1-2 shift valve 500 is positioned as shown in the right half of FIG. 4, and as a result, the first input port 505 and Second input port 507
Is closed and the third input port 509 communicates with the third brake port 510. And the first brake port 5
06 is cut-off valve 800 and modulator valve 1
07 via the second brake port 508
Is connected to the second brake B2, and the third brake port 510 is connected to the third brake B3 via the check ball valve 103.

The 2-3 shift valve 600 is switched by the first solenoid valve S1. A spring 602 is arranged at one end of a spool 601 having six lands, and a hold port is provided here. 611 is formed, and this hold port 611 is formed.
The fifth solenoid valve S5 is connected to, and the line pressure PL acts on the hold port 611 when the fifth solenoid valve S5 is on. A control port 603 is formed at the end opposite to the spring 602, and the first solenoid valve S1 is connected to this control port 603. The first solenoid valve S1 is provided in the D range oil passage 112 described above.
Alternatively, it is for supplying / discharging the hydraulic pressure sent from the engine brake range oil passage 113 via the check ball valve 104 to / from the control port 603, and by closing the drain port in the OFF state, the control port 603 is controlled. The line pressure PL is generated, and the drain port is opened to discharge the pressure from the control port 603 in the ON state.

2-3 The line pressure PL acts on the control port 603 of the shift valve 600 and the hold port 6
Then, the spool 601 is pushed down to the position shown in the left half of FIG. 5, whereby the first input port 604 connecting the line pressure oil passage 102 and the clutch port 605 communicate with each other. Further, the second input port 606 connected to the engine brake range oil passage 113 communicates with the hold output port 607, and the third input port 608 connected to the engine brake range oil passage 113 is closed. .. Also control port 6
When the spool 601 is pushed up to the position shown in the right half of FIG. 5 by being discharged from 03 or by the line pressure PL acting on the hold port 611, the first input port 604 communicates with the hold output port 607, and The second input port 606 communicates with the first brake port 609, and the third input port 608 communicates with the second brake port 610. Of these ports, the first brake port 609 is connected to the first input port 505 of the 1-2 shift valve 500, and the clutch port 605 is passed through the check ball valve 105 having two input ports and one output port. Second clutch C2 and 1-2
It is connected to the hold port 503 of the shift valve 500, and the second brake port 610 is further connected via the modulator valve 106 to the third of the 1-2 shift valve 500.
It is connected to the input port 509. The other input port of the check ball valve 105 is connected to the R range oil passage 110.

The 3-4 shift valve 700 has a spool 701 having four lands and a spring 702 arranged at one end side thereof, and the 2-3 shift valve described above is provided at the end portion where the spring 702 is arranged. Hold port 70 connected to hold output port 607 in 600
3 is formed, and the control port 70 to which the second solenoid valve S2 is connected is provided at the end opposite to this.
4 are formed. When the pressure is discharged from the hold port 703 and the line pressure PL is generated in the control port 704, the spool 701 is pushed down to the position shown in the left half of FIG. 4, and the input port 705 connected to the line pressure oil passage 102 becomes , The brake B0 is connected to the connected brake port 706, and when the pressure is discharged from the control port 704, the spool 701 is pushed up to the position shown in the right half of FIG. 4, and the input port 705 connects the clutch C0. It communicates with the clutch port 707.

The cut-off valve 800 pushes the spool 801 down to the position shown in the right half of FIG. 4 as the throttle pressure increases in accordance with the throttle opening, thereby reducing the flow passage area from the input port 802 to the output port 803. A shift valve whose input port 802 is through the modulator valve 107 to the 1-2 shift valve 50.
No. 0 first brake port 506. Further, the output port 803 is connected to the first brake B1.

The parking lock mechanism comprises two valves, a control valve 900 and a switching valve 910, and a hydraulic servo 920. Its control valve 900
Is a valve that outputs the hydraulic pressure supplied when the parking range is selected from either of the two output ports, including a spool 901 having four lands, and a spring 902 arranged on one end side of the spool 901. And a control port 903 formed on the side opposite to the spring 902 is connected to the second solenoid valve S2. The control valve 900 has one input port 904, two output ports 905 and 906, and two drain ports 907 and 908, and the input port 904 is connected to the parking range oil passage 111. .. When the pressure is discharged from the control port 903 and the spool 901 is pushed up to the position shown in the right half of FIG. 5, the input port 904 communicates with one output port (tentatively, the first output port) 905, And the other output port (provisionally the second output port) 906
Communicates with the drain port 908. Also control port 90
When the spool 901 is pushed down to the position shown in the left half of FIG. 5 due to the high hydraulic pressure applied to 3,
The input port 904 communicates with the second output port 906, and the first output port 905 communicates with the drain port 907.

Further, the switching valve 910 is a valve for switching the input hydraulic pressure between the locking port and the non-locking port and outputting it, and has a spool 91 having four lands.
1 and a spring 912 that presses the spring 912 toward one end side, and a control port 913 that applies hydraulic pressure in a direction of compressing the spring 912 is formed at the end opposite to the end where the spring 912 is provided. The control port 913 is connected to the linear solenoid valve SLU that controls the lockup clutch 1. Further, the switching valve 910 includes two input ports 914 and 915, two non-locking ports 916 and 917, and one lock port 918, and one of the input ports (tentatively, the first input port). ) 914 is connected to the first output port 905, and the other input port (provisionally a second input port) 915 is connected to the second output port 90.
Connected to 6.

When the pressure is exhausted from the control port 913 by the linear solenoid valve SLU, the spool 912 is released.
Is pushed up to the position shown in the left half of FIG. 5, the first input port 914 communicates with the lock port 918, and the second input port 915 is one of the non-locking ports (for example, the second non-locking port). Communication) to 917. Further, when the hydraulic pressure of the control port 912 is increased by the linear solenoid valve SLU, the spool 911 is pushed down to the position shown in the right half of FIG. 5, and the first input port 914 causes the other unlocking port (provisionally, the first unlocking port). Port 916 and the second input port 915 communicates with the lock port 918.

The hydraulic servo 920 is configured as a so-called double-acting cylinder, and a forward port 922 for applying hydraulic pressure to move the piston 921 forward (to the right in FIG. 5) is provided at the lock port 918. A return port 92 that is connected and applies hydraulic pressure to retract the piston 921 (moves to the left in FIG. 5).
3 is connected to the two non-locking ports 916 and 917 communicating with each other. Also the piston 921
Conical cam 925 on rod 924 integrated with
Is fitted so as to move back and forth within a certain range, and this cam 9
25 is forward by the spring 926 (rightward in FIG. 5)
Is pressed against. A recess is formed at the base end of the rod 924, and a ball 927 fitted therein is pressed by a spring 928 toward the axial center of the rod 924. That is, the detent mechanism is formed here. When the piston 921 moves forward, the cam 925 rotates the parking lock pole 929 to prevent the output shaft 15 from rotating. More specifically, the parking lock pole 929 engages with the ring gear 14 on the rear side in FIG. 2 to prevent its rotation, thereby fixing the output shaft 15.

A hydraulic switch PS1 is connected to the output side of the check ball valve 104 connecting the oil passage 112 for the D range and the oil passage 113 for the engine brake range, and the oil pressure of the third brake B3 is detected. A hydraulic switch PS2 is provided. Further, the R range oil passage 110 and the D range oil passage 112 are connected to a hydraulic switch PS3 via a check ball valve 114.
The hydraulic switches Ps1 to Ps3 are electrically connected to the range switching ECU 19.

In the automatic transmission equipped with the above-described shift control device, the first to fifth solenoid valves S1 to S5 are provided.
By controlling ON / OFF of the linear solenoid valve SLU as shown in the operation table of FIG. 6, each friction engagement device is engaged or released as shown in the operation table of FIG. It In FIG. 6, for the solenoid valve, ○ indicates ON, × indicates OFF, and other marks indicate ON or OFF. For the friction engagement device, ○ indicates engagement, X indicates release, The other marks indicate that they may be engaged or released, respectively.

The P range and the N range are set by supplying hydraulic pressure to a predetermined location through the above-mentioned parking range oil passage 111, and similarly, the R range is set through the R range oil passage 110 through the D range. The range is set by supplying hydraulic pressure to predetermined locations via the D range oil passage 112 and the engine brake range via the engine brake range oil passage 113, respectively. The hydraulic pressure supply / discharge states for setting these ranges are the third to fifth states.
This is achieved by controlling the range switching valves 200, 300 and the switching valve 400 by the solenoid valves S3, ...
The on / off states of the solenoid valves S3 to S5 are different depending on whether or not there is a failure.

That is, FIGS. 7 (A) to 7 (F) show that the third to fifth solenoid valves S3, S5 are turned on.
FIG. 7A is an operation table in the case of a normal state without a failure or a failure in which the fifth solenoid valve S5 remains in the off state. Note that this is the same as that shown in FIG. In this case, the fifth solenoid valve S5 is off regardless of which range is set, whereas the third solenoid valve S3 and the fourth solenoid valve S4 are both turned on when setting the R range. It Therefore, in the first range switching valve 200, the spool 201 is pushed up as shown in the right half of FIG.
The hydraulic pressure is supplied from 05 to the first input port 304 of the second range switching valve 300. Also in this second range switching valve 300, since the spool 301 is exhausted from the control port 303 and pushed up to the position shown in the right half of FIG. 3, the parking port 306 communicates with the first input port 304. From here, the switching valve 40
The hydraulic pressure is output to the first input port 405 of 0. Further, in the switching valve 400, since the spool 401 is pushed up to the position shown in the right half of FIG. 3, the first input port 405 communicates with the R port 410, and thus the R range oil passage 110 connected thereto. Hydraulic pressure is sent to each check ball valve 103, 105 via.

When the N (or P) range is selected, both the third solenoid valve S3 and the fourth solenoid valve S4 are turned off. Therefore, in the first range switching valve 200, the hydraulic pressure is output from the second output port 206, which is the second range switching valve 300.
To the second input port 305 of the. Further, in the second range switching valve 300, the spool 301 is lowered to the position shown in the left half of FIG.
It communicates with the range port 311 and the switching valve 40 is connected from here.
The hydraulic pressure is sent to the second input port 406 of 0. Since the spool 401 of this switching valve 400 is in the position shown in the right half of FIG. 3 as in the case described above, the second input port 40
6 communicates with the second parking port 411, so that the hydraulic pressure is output to the parking range oil passage 111.

Further, when the D range is selected, the third solenoid valve S3 is turned on and the fourth solenoid valve S4 is turned on.
Is turned off. Therefore, the first range switching valve 20
Since 0 is the same as the case of the above R range,
From the first output port 205 to the second range switching valve 3
The hydraulic pressure is supplied to the first input port 304 of No. 00, but in the second range switching valve 300, the control port 303
Since the line pressure PL is being supplied to the spool 301, the spool 301 is pushed down to the position shown in the left half of FIG. 3, and therefore the first input port 304 communicates with the D range port 307, from which the D range oil passage is formed. The hydraulic pressure is sent from the check ball valve 104 to the first clutch C1 via 112.

On the other hand, when the engine brake range is selected, the third solenoid valve S3 is turned off and the fourth solenoid valve S4 is turned on. Therefore the first
In the range switching valve 200, the spool 201 is pushed down to the position shown in the left half of FIG. 3 so that the second output port 206 moves the second range switching valve 300 to the second position.
Hydraulic pressure is sent to the input port 305. In the second range switching valve 300, the spool 301 is pushed up to the position shown in the right half of FIG. 3 as in the case of the R range described above, so the second input port 305 communicates with the engine brake port 308, and from here. Oil pressure is sent to the engine brake range oil passage 113, and from there, oil pressure is sent to the first clutch C1 via the check ball valve 104, while oil pressure is sent to the 2-3 shift valve 600.

FIG. 7B shows the third solenoid valve S3.
6 is an operation table in the case where a failure occurs in which is kept off. In this case, in the first range switching valve 200,
Since the spool 201 remains pushed down to the position shown in the left half of FIG. 3, the hydraulic pressure is constantly output from the second output port 206. Therefore, when the R range is selected, the fourth solenoid valve S4 is turned off and the fifth solenoid valve S5 is turned on. As a result, hydraulic pressure is output from the R range port 311 of the second range switching valve 300, and this R range port 311 is output.
Second input port 4 of the switching valve 400 to which is connected
No. 06 is in communication with the R port 410 because the spool 401 is lowered to the position shown in the left half of FIG.
Oil pressure is output to the range oil passage 110.

When the N range is selected, both the fourth solenoid valve S4 and the fifth solenoid valve S5 are turned off. This is similar to the normal N range described above.

When the D range is selected, the fourth solenoid valve S4 is turned on and the fifth solenoid valve S5 is turned off. This is the same as the engine brake range in the normal state described above, so that four forward gears can be set, and the engine brake is effective in the first speed and the second speed.

When the engine braking range is selected, the fourth solenoid valve S4 is turned on, but the fifth solenoid valve S5 may be turned on or off. That is, when the fifth solenoid valve S5 is turned on, the hydraulic pressure is supplied to the hold port 611 of the 2-3 shift bar luer 600, and the spool 601 of FIG.
Will be pushed up to the position shown in the right half of
It becomes impossible to set the third speed and the fourth speed,
Normally, the first speed and the second speed are used in the engine brake range, so there is no problem even if the fifth solenoid valve S5 is on.

FIG. 7C shows the third solenoid valve S3.
When the R range is selected in the operation table in the case where a failure occurs in which is kept on, the fourth solenoid valve S4 is turned on and the fifth solenoid valve S5 is turned off. This is the same as the R range in the normal state.

When the N range is selected, the fourth range is selected.
Then, both the fifth solenoid valves S4 and S5 are turned on. That is, when both the third solenoid valve S3 and the fourth solenoid valve S4 are turned on, hydraulic pressure is output from the parking port 306 of the second range switching valve 300, which is the first input port 405 of the switching valve 400.
Sent to. In the switching valve 400, the fifth solenoid valve S5 is on and the spool 401 is in the position shown in FIG.
By being pushed down to the position shown in the right half of
The hydraulic pressure is output to the parking range oil passage 111, which communicates with the first parking port 410.

When the D range and the engine brake range are selected, the fourth solenoid valve S4 and the fifth solenoid valve S5 are turned off in both cases. This is the same as when the D range is selected in the normal state, and four forward gears can be set. In this case, since hydraulic pressure cannot be output to the engine brake range oil passage 113, engine braking does not work in the first speed and the second speed.

FIG. 7D shows the fourth solenoid valve S4.
Is an operation table in the case where a failure occurs in which is kept in the off state. In this case, the hydraulic pressure always acts on the control port 303 of the second range switching valve 300, and the spool 3
01 remains pushed down to the position shown in the left half of FIG. Therefore, if the R range is selected, the third
The solenoid valve S3 is turned off, and the fifth solenoid valve S
Turn on 5. This is similar to the case of the R range shown in FIG.

When the N range is selected, the third range is selected.
Solenoid valve S3 and fifth solenoid valve S5
Both off. This is the same as the N range at the time of failure shown in FIG.

Further, regardless of whether the D range is selected or the engine braking range is selected, the third solenoid valve S3 is turned on and the fifth solenoid valve is turned on as in the case of the failure shown in FIG. 7C. Turn off solenoid valve S5. Therefore, also in this case, the engine braking does not work in the first speed and the second speed in the engine braking range.

FIG. 7E shows the fourth solenoid valve S4.
Is an operation table in the case where a failure occurs in which the ON state remains in the ON state. In this case, the hydraulic pressure remains discharged from the control port 303 of the second range switching valve 300, and the spool 301 of FIG. It remains pushed up to the position shown in the right half. Therefore, when the R range is selected, the third solenoid valve S3 is turned on and the fifth solenoid valve S5 is turned off. This is the same as the R range in the normal state.

When the N range is selected, the third range is selected.
Solenoid valve S3 and fifth solenoid valve S5
Together turn on. This is the same as the N range at the time of failure shown in FIG.

Whether the D range is selected or the engine braking range is selected, the third solenoid valve S3 and the fifth solenoid valve S5 are turned off. This is the same as the D range at the time of failure shown in FIG.

FIG. 7F shows the fifth solenoid valve S5.
FIG. 3 is an operation table in the case where a failure occurs in which the ON state remains in the ON state. In this case, the hydraulic pressure always acts on the control port 403 of the switching valve 400, and the spool 401 of FIG.
It remains pushed down to the position shown in the left half of. Also
The hydraulic pressure remains supplied to the hold port 611 of the 2-3 shift valve 600.
Spool 601 turns on the first solenoid valve S1.
It remains pushed up to the position shown in the right half of FIG. 5 regardless of the off state. That is, the state of setting the first speed or the second speed is maintained. Therefore, in this case, if the R range is selected, the third solenoid valve S3 and the fourth solenoid valve S3
Turn off both solenoid valves S4. This is the same as in the case of the failure shown in FIG. When the N range is selected, the N at the time of failure shown in FIG.
As with the range, both the third solenoid valve S3 and the fourth solenoid valve S4 are turned on. Further, when the D range is selected, the third solenoid valve S3 is turned on and the fourth solenoid valve S4 is turned off.
Therefore, hydraulic pressure is output from the D range port 307 of the second range switching valve 300 to the D range oil passage 112.
In this case, since the hydraulic pressure is supplied from the fifth solenoid valve S5 to the hold port 611 of the 2-3 shift valve 600, only the first speed and the second speed can be set in the forward stage.

When the engine brake range is selected, if the third solenoid valve S3 is turned off and the fourth solenoid valve S4 is turned on, (A) of FIG.
In the same manner as in the normal time shown in, the hydraulic pressure is output from the engine brake port 308 of the second range switching valve 300 to the engine brake range oil passage 113. Therefore, in this case, the engine braking can be applied in the first speed and the second speed.

In the control device described above, the 2-3 shift valve 600 can be controlled by the fifth solenoid valve S5. Therefore, even if the first solenoid valve S1 fails to maintain the OFF state, the first speed through the fourth speed. It is possible to perform forward traveling at high speed. FIG. 8 is an operation table for that purpose. That is, in this case, the first solenoid valve S1 remains off, and the hydraulic pressure always acts on the control port 603 of the 2-3 shift valve 600. Therefore, in the first speed and the second speed in the D range, the third solenoid valve S3 is turned on, the fourth solenoid valve S4 is turned off, and the fifth solenoid valve S5 is turned on. Accordingly, in the first range switching valve 200, hydraulic pressure is output from the first output port 205 by discharging pressure from the control port 203, and in the second range switching valve 300, hydraulic pressure acts on the control port 303. , First input port 304 to which hydraulic pressure is supplied
Communicates with the D range port 307, from which hydraulic pressure is output to the D range oil passage 112. On the other hand, when the fifth solenoid valve S5 is turned on, the hydraulic pressure is supplied to the hold port 611 of the 2-3 shift valve 600 and the spool 601 is pushed up to the position shown in the right half of FIG. When the Neute valve S2 is turned on and off as shown in FIG.
The speed is set.

If the fifth solenoid valve S5 is turned off from this state, the pressure is discharged from the hold port 611 of the 2-3 shift valve 600, so that the spool 601
Is pushed down to the position shown in the left half of FIG. 5, resulting in
As the second solenoid valve S2 is turned on and off as shown in FIG. 6, the third speed or the fourth speed is set.

On the other hand, in the first speed or the second speed with the engine brake range selected, the third solenoid valve S3 is turned off, and the fourth and fifth solenoid valves S4, S5 are both turned on. Set each. Since this is similar to the engine brake range shown in FIG. 7F, hydraulic pressure is supplied to the engine brake range oil passage 113. When the hydraulic pressure is supplied from the fifth solenoid valve S5 to the hold port 611 of the 2-3 shift valve 600, the spool 601 is pushed up to the position shown in the right half of FIG. 5 to drive the first speed or the second speed. It is ready to be set. If the fifth solenoid valve S5 is switched off from this state, the spool 601 of the 2-3 shift valve 600 is pushed down by the hydraulic pressure acting on the control port 603 to the position shown in the left half of FIG. It is in a state where the fourth speed can be set.

The present invention is not limited to the above embodiment, but may be applied to an automatic transmission having a gear train other than the gear train shown in FIG. The hydraulic circuit is also shown in FIGS.
It is not limited to the configuration shown in.

[0061]

As is apparent from the above description, according to the gear shift control device of the present invention, gear shifting is performed between the gear stage in which the engine brake is effective in the engine brake range and the gear stages other than the gear stage. Since the shift valve is configured to be controlled by the solenoid valve originally provided for the shift valve and the other emergency solenoid valves, even if the solenoid valve or its control system fails, the engine brake It is possible to effectively perform forward traveling and release the engine brake during forward traveling, and it is possible to secure stable traveling during a failure.

[Brief description of drawings]

FIG. 1 is a block diagram showing a basic configuration of the present invention.

FIG. 2 is a block diagram schematically showing an embodiment of the present invention.

FIG. 3 is a partial hydraulic circuit diagram showing a part of a hydraulic circuit in one embodiment of the present invention.

FIG. 4 is a partial hydraulic circuit diagram showing another portion of the hydraulic circuit in the embodiment of the present invention.

FIG. 5 is a partial hydraulic circuit diagram showing still another portion of the hydraulic circuit in the embodiment of the present invention.

FIG. 6 is an operation table of each solenoid valve and each friction engagement device for setting each shift speed.

FIG. 7 is an on / off operation table of the third to fifth solenoid valves at the normal time and the fail time.

FIG. 8 is an on / off operation table of the third to fifth solenoid valves when the first solenoid valve fails to the off side.

[Explanation of symbols]

 V1 solenoid valve V2 range switching valve V3 other solenoid valve V4 shift valve M1 fail detection means M2 shift detection means V5 emergency solenoid valve

Claims (1)

[Claims] 1. A range switching valve which is operated by a solenoid valve to switch a hydraulic pressure supply state so as to set a plurality of traveling ranges, and a shift stage which applies an engine brake by a hydraulic pressure generated when an engine brake range is selected. A shift control device for an automatic transmission, comprising: a shift valve that is switched by another solenoid valve so as to perform a shift to and from another shift stage; a fail detecting a failure of the other solenoid valve. And a shift detecting means for detecting that the shift stage set by switching the shift valve operating due to the failure of the other solenoid valve to another state is selected. The fail detection means detects a failure of the other solenoid valve and When the detecting means detects that the shift stage set by switching the shift valve is selected, the shift valve is changed from the state set by the fail of the other solenoid valve to another state. A shift control device for an automatic transmission, comprising: an emergency solenoid valve that supplies a hydraulic pressure for forcibly switching without passing through the range switching valve.