JPS61144458A - Failure diagnosis device for automatic transmission gear - Google Patents

Abstract

PURPOSE:To enable an auxiliary speed-change control to be performed even if one of the electromagnetic means gets out of order by equipping not less than three electromagnetic speed-change means for controlling the supply of oil pressure and combing 'ON' 'OFF' operations of these electromagnetic means. CONSTITUTION:When a solenoid driving system consisting of three electromag netic means is judged to be in a fault condition, firstly, the input of the present car speed VSP' is operated in the steps S71, 72, and secondly, a judgement is made whether a car speed VSP1 corresponding to the present throttle opening read out from an up-shift map is smaller than said speed VSP'. As a result, if VSP'>VSP1, the other two solenold driving systems in normal condition are used for the purpose so that an auxiliary up-shit can be performed.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention controls the supply of hydraulic pressure to a fluid actuator of a gear type transmission mechanism by a combination of ON and OFF of a plurality of electromagnetic means for speed change, thereby generating power. In an automatic transmission that switches transmission, that is, changes gears, when some of the electromagnetic means for shifting fails, the remaining normally operating electromagnetic means for shifting is used to perform emergency (auxiliary) gear shifting control. The present invention relates to a fault diagnosis device for an automatic transmission.

(Prior Art) Generally, automatic transmissions are constructed by combining a torque converter and a multi-stage gear type transmission mechanism having a gear mechanism such as a planetary gear mechanism. For speed change control in such automatic transmissions, a hydraulic mechanism is usually adopted, and the hydraulic circuit is switched by an electromagnetic switching valve, thereby controlling the brake as a fluid actuator attached to the multi-stage gear type transmission mechanism. The engine power transmission system is switched by operating friction elements such as clutches as appropriate.
The required gear stage is obtained. In order to switch the hydraulic circuit using an electromagnetic switching valve, an electronic control device detects that the vehicle's running state has exceeded a predetermined shift line, and an electromagnetic control device is activated by a shift up signal or a shift down signal from this device. It is customary to selectively operate a type switching valve, thereby switching the hydraulic circuit and changing speed.

By the way, in such an electromagnetic means for speed change, if a failure occurs in the electromagnetic means for speed change, desired speed change control cannot be performed. For this reason, JP-A-57-116957
As shown in the publication, normally two speed change electromagnetic means are used to perform multi-stage speed change control by the combination of ON and OFF, but if one of the speed change electromagnetic means fails, the remaining Using only one normal gear shifting electromagnetic means, the gear closest to the gear before the failure (closer gear ratio)
A system has been proposed in which the gear is fixed to a gear position to at least avoid a situation in which the vehicle becomes unable to drive.

However, the method described in the above publication has the following problems.

That is, since there is only one emergency gear in the event of a failure of the electromagnetic means for shifting, this will cause considerable problems in driving.

Furthermore, in the above-mentioned publication, only a failure of the speed changing electromagnetic means itself is considered as a failure of the speed changing electromagnetic means, and the speed changing electromagnetic means is ON (short circuit) or OF.
It is assumed that it is possible to determine whether or not there is a failure in the state of F (broken wire), but it is assumed that a failure (broken wire or short circuit) of the power supply transistor that controls the power supply to the electromagnetic means for speed change.
Considering this possibility, it is practically impossible to determine whether the failure occurs when the electromagnetic means for speed change is in the ON state or the failure is in the OFF state. For this reason, it has become impossible to select the manner in which the remaining normal transmission electromagnetic means should be operated, and it has also become impossible to select a desired emergency gear. That is, whether or not the electromagnetic means for speed change is out of order can be determined by the presence of a "high" or "high" signal between the base of the power supply transistor and the output terminal of the collector or emitter.
This is generally done by looking at the 'low' relationship. And always "high" between this base and the output end,
The power supply transistor and the electromagnetic means for speed change are normal when a potential difference of "low" is generated, and the difference between the base and the output terminal is "high" and "high" or "4-" and "low". When there is no difference, it means that the power supply transistor or the electromagnetic means for speed change has failed.

The manner in which this failure is determined is, for example, if the power supply transistor is normal and the electromagnetic means for speed change is disconnected, and it appears as a signal form of "high" and "high" (in this case, the electromagnetic means for speed change is OF Even if it is "high", the electromagnetic means for speed change is turned on.

(Object of the invention) The present invention has been made in consideration of the above circumstances, and
If one of the plurality of speed change electromagnetic means fails,
It is an object of the present invention to provide a failure diagnosis device for an automatic transmission that is capable of performing auxiliary gear shift control using a plurality of gear stages as an emergency, regardless of whether the electromagnetic means for gear shifting is in an ON or OFF state. do.

(Structure of the Invention) Basically, the present invention provides at least three or more transmission electromagnetic means for controlling the hydraulic pressure supply to the hydraulic actuator of a gear type transmission mechanism, and turns ON and OFF by the transmission electromagnetic means. This combination allows for greater flexibility in the hydraulic pressure supply mode to the actuator. In other words, even if one of the transmission electromagnetic means drive systems including the transmission electromagnetic means breaks down, at least two remaining normally operating electromagnetic means can be used to turn on and off the transmission electromagnetic means.
Depending on the combination of F, auxiliary shift control is performed at a plurality of gears, although the number of gears is fewer than in normal conditions.

Specifically, as shown in FIG. 1, at least three devices control the supply of pressure fluid to a gear-type transmission mechanism interposed in the engine drive system and a fluid-type actuator that performs a speed change operation of the gear-type transmission mechanism. A shift up signal or a shift down signal is output to each of the transmission electromagnetic means, based on the transmission electromagnetic means and predetermined main transmission characteristics, thereby controlling the transmission of at least three or more gears. The main speed change control means and the speed change electromagnetic means also receive a failure detection means for detecting a failure and an output from the failure detection means, so that when the speed change electromagnetic means drive system fails, control by the main speed change control means is performed. In response to the output from the prohibition means and the failure detection means, and when the electromagnetic means for speed change fails, the remaining two
auxiliary shift control means that uses three or more normally operating shift electromagnetic means to perform shift control at a plurality of gears less than the gears under the main shift control;

This is a configuration equipped with the following.

(Example) Examples of the present invention will be described below based on the attached drawings.

In FIG. 2, which shows a cross section of a mechanical part and a hydraulic control circuit of an electronically controlled automatic transmission, the automatic transmission AT includes a torque converter 10, a multi-gear transmission mechanism 20, and a torque converter 10 and a multi-gear transmission mechanism 20. and an overdrive planetary gear transmission mechanism 50 disposed between the two.

The torque converter IO includes a pump 11 coupled to an engine output shaft 1, a turbine 12 disposed opposite the pump 11, and a stator 13 disposed between the pump 11 and the turbine 12. A converter output shaft 14 is coupled to the converter output shaft 14 . A lock-up clutch 15 is provided between the converter output shaft 14 and the pump 11.
It is arranged as shown. This lock-up clutch 15 is
The hydraulic pressure circulating through the torque converter output shaft constantly urges the engine output shaft 1 and the torque converter output shaft 14 in the direction of lock-up (direct connection), and the release hydraulic pressure supplied from the outside It is kept open.

The multi-stage gear transmission mechanism 20 has a front planetary gear mechanism 21 and a rear planetary gear mechanism 22, and a sun gear 23 of the front planetary gear mechanism 21 and a sun gear 24 of the rear planetary gear mechanism 22 are connected via a connecting shaft 25. There is. Multi-stage gear transmission mechanism 2
0 input shaft 26 is connected to the connecting shaft 2 via the front clutch 27.
5 and an internal gear 29 of the front planetary gear mechanism 21 via a rear clutch 28. Connection shaft 25 or sun gear 23.24
A front brake 30 is provided between the front brake and the transmission case. Planetary carrier 3 of the front planetary gear mechanism 21
1 and the internal gear 33 of the rear planetary gear mechanism 22 are connected to an output shaft 34, and a rear brake 36 and a one-way clutch 37 are interposed between the planetary carrier 35 of the rear planetary gear mechanism 22 and the transmission case. There is.

In the overdrive planetary gear transmission mechanism 50,
A planetary carrier 52 that rotatably supports a planetary gear 51 is connected to the output shaft 14 of the torque converter 10, and the sun gear 53 is connected to an internal gear 55 via a direct coupling clutch 54 = sun gear 53 and speed change An overdrive brake 56 is provided between the machine case and the internal gear 55, and the internal gear 55 is connected to the input shaft 26 of the multi-gear transmission mechanism 20.

The multi-gear transmission mechanism 20 is of a conventionally known type and has three forward speeds and one reverse speed, and can obtain the desired speed by appropriately operating the clutches 27, 28 and brakes 30, 36. The overdrive planetary gear transmission mechanism 50 connects the shafts 14 and 26 in a direct connection state when the direct coupling clutch 54 is engaged and the brake 56 is released; When released, the shaft 14.26 is coupled in overdrive.

The automatic transmission AT described above includes a hydraulic control circuit GK as shown in FIG. This hydraulic control circuit CK
has an oil pump 100 driven by an engine output shaft l, and hydraulic oil discharged from the oil pump 100 into a pressure line 101 has its pressure adjusted by a pressure regulating valve 102 and is guided to a select valve 103. The select valve 103 has shift positions of 1, 2, D, N, R, and P, and when the select valve 103 is in the 1.2 and D positions, the pressure line 101 is connected to the port of the select valve 103. a
, b, and c. Boat a is connected to an actuator 104 for operating the rear clutch 28, and a valve 103
When the rear clutch 28 is in the above-mentioned position, the rear clutch 28 is held engaged.

Boat a is also connected near the left end of the 1-2 shift valve 110, pushing its spool to the right in the figure. Boat a further receives 1 via the first line Ll.
- Connected to the right end of the 2-2 shift valve 110, to the right end of the 2-3 shift valve 120 via the second line L2, and to the right end of the 3-4 shift valve 130 via the third line L3. has been done.

The first, second and third lines Ll, L2 and L
3 to fJIJl, second and third drain lines DL1.3, respectively. DL2 and DL3 are branched, and these drain lines DLI, DL2, and DL3 have a first line that opens and closes the drain lines DLI, DL2, and DL3. Second and third solenoid valves SLI, SL2, and SL3 are connected. The above solenoid valve SL1. SL2, S
When L3 is demagnetized with line 101 and boat a communicating, each drain line DLL, DL2, DL3
, thereby increasing the pressure in the first, second, and third lines.

Boat b is also connected to second lock valve 105 via line 140, and this pressure acts to push the spool of second lock valve 105 downward in the figure. When the spool of the second lock valve 105 is in the downward position, the lines 140 and 141 communicate with each other, and hydraulic pressure is introduced into the engagement side pressure chamber of the actuator 108 of the front brake 30 to hold the front brake 30 in the operating direction. . Boat C is connected to second lock valve 105, and this pressure acts to push the spool of second lock valve 105 upward. Furthermore, boat c is connected to a 2-3 shift valve 120 via a pressure line 106. this line 1
06 is the solenoid valve SL2 of the second drain line DL2
is demagnetized to increase the pressure in the second line L2, which communicates with the line 107 when the spool of the 2-3 shift valve 120 is moved to the left. The line 107 is connected to the release side pressure chamber of the actuator 108 of the front brake 30, and when hydraulic pressure is introduced into the pressure chamber, the actuator 108 moves the brake 30 in the release direction against the pressure of the engagement side pressure chamber. Activate. The pressure in line 107 is also directed to actuator 109 of forward clutch 27, causing this clutch 27 to engage.

The select valve 103 is connected to the pressure line 101 in one position.
has a boat d leading to the line 11.
2 to reach the l-2 shift valve 110, and then line 1
13 to the actuator 114 of the rear brake 36. The 1-2 shift valve 110 and the 2-3 shift valve 120 operate solenoid valves SLI and SLI in response to predetermined signals.
When L2 is demagnetized, the spool is moved to switch the line, thereby operating a predetermined brake or clutch to perform the 1-2 and 2-3 speed change operations, respectively. Further, the hydraulic control circuit CK includes a cutback valve 115 that stabilizes the hydraulic pressure from the pressure regulating valve 102, a vacuum throttle valve 116 that changes the line pressure from the pressure regulating valve 102 according to the magnitude of the intake negative pressure, and this throttle valve 11.
A throttle back-up valve 117 is provided to assist 6.

Further, the hydraulic control circuit CK of this example is provided with a 3-4 shift valve 130 and an actuator 132 to control the clutch 54 and brake 56 of the overdrive planetary gear transmission mechanism 50. The engagement side pressure chamber of the actuator 132 is connected to the pressure line 101, and the pressure of the line 101 pushes the brake 56 in the engagement direction. This 3-4 shift valve is also
- Similar to the 2 and 2-3 shift valves 110 and 120, when the solenoid valve SL3 is demagnetized, the spool 131 of the 3-4 shift valve 130 moves downward, the pressure line lot and the line 122 are cut off, and the line 122 is drained.

As a result, the hydraulic pressure acting on the release side pressure chamber of the actuator 132 of the brake 56 disappears, and the brake 56 is actuated in the engaging direction, and the actuator 134 of the clutch 54 acts to release the clutch 54.

Further, the hydraulic control circuit GK of this example is provided with a lock-up control valve 133.
33 is the port a of the select valve 103 via the line L4.
is communicated with. From this line L4, drain line DL1. A drain line DL4, which is provided with a solenoid valve SL4 similar to DL2 and DL3, branches off. The lock-up control valve 133 is configured such that when the solenoid valve SL4 is energized, the drain line DL4 is closed, and the pressure in the line L4 is increased, the spool cuts off the lines 123 and 124, and the line 124 is drained and the lock-up control valve 133 is activated. The clutch 15 is moved in the operating direction.

In the above configuration, the operational relationship between each gear stage, lockup, and each solenoid, and the operational relationship between each gear stage, clutch, and brake are shown in Tables 1 to 3 below.

Table 1, Table 2, and FIG. 3 show a system according to the present invention which controls the hydraulic control circuit CK associated with the above-mentioned automatic transmission AT to perform main and auxiliary shift control and lock-up control. An example of a control device for the automatic transmission AT is shown together with an engine EN incorporating the automatic transmission AT.

In FIG. 3, the control unit 200 includes first to third solenoids 5L as electromagnetic means for speed change, as in the conventional case.
In addition to each drive function (circuit) that drives I-5L3 and the fourth solenoid SL4, automatic speed change I! In addition to having a lock-up control function that performs lock-up control for the AT and a main shift control function that performs speed change control when the drive system of each solenoid SLI to SL3 is normal, each solenoid drive system including each solenoid SL1 to SL3 If one of the solenoid drive systems fails, the main shift control function will be stopped and the remaining two solenoid drive systems will stop.
It has an auxiliary shift control function that performs shift control using two normal solenoid drive systems. Such a control unit 200 includes a throttle opening signal from a throttle sensor LS that detects the throttle opening T)I, a turbine rotation, that is, an output shaft rotation speed TSP of the torque converter 10.
The turbine rotation speed signal from the turbine sensor TS that detects the output shaft rotation speed of the gear type transmission mechanism 20, that is, the vehicle speed v
A vehicle speed signal from a vehicle speed sensor AS that detects SP is input.

The control unit 200 that performs the above-mentioned control can be configured, for example, by a microcomputer, and the operating program of the microcomputer configuring the control unit 200 is, for example, as shown in FIGS. 5 to 12.
The process is executed according to the flowchart shown in the figure. This flowchart will be sequentially explained below.

Overall Control FIG. 5 shows an overall flowchart of the shift control, and as can be seen from this figure, the shift control is first performed from the initialization setting in step SO. This initialization setting initializes the ports of each control valve that switches the hydraulic control circuit of the automatic transmission and necessary counters to set the gear transmission mechanism 20 to the first speed and the lock-up clutch 15 to disengage. After this, various working areas of the control unit 200 are initialized and the process is completed. Next, in step S1, it is determined whether or not a failure has occurred in the electromagnetic manual drive system for speed change, that is, each of the solenoids SLI to SL3 and their drive circuits. When any one of the solenoid drive systems is determined to be in failure,
After releasing the lockup in step 515, step S
At step 16, auxiliary shift control is performed. If it is determined in step S1 that there is no failure, the routine moves to step S2, where normal control, that is, main shift control and lock-up control, is performed. If it is determined in step S1 that there is no failure, the process moves to step S2, where normal control, that is, main shift control and lock-up control, is performed. The failure determination and auxiliary shift control in step SL described above will be described in detail later, but the steps from step S2 onwards, which are control during normal operation, will be explained first.

Control during normal operation, that is, main shift control and lock-up control, is performed based on predetermined main shift characteristics and lock-up characteristics as shown in FIG. The process starts by reading the position of the select valve 103, that is, the shift range.

Then, in step S3, it is determined whether the read shift range is the "°l range". When the shift range is in the "l range", the lockup is released in step S4, and then the shift is down to the first speed in Stella 7'S5, and it is calculated whether or not the engine will overrun. When it is determined in step S6 that an overrun occurs, the shift valve is controlled to shift the gear transmission mechanism 20 to the second speed in step S7. When it is determined that there is no overrun, the gear is shifted to the first gear in step S8 to prevent shift shock.

If the shift range is not in the range '2' in Stella 7'S3, it is determined in step S9 whether the shift range is in the '2 range'. When the shift range is in the "2 range", lock-up is released in step SIO, and then the gear is shifted to second speed in step Sll. On the other hand, if it is determined in step S9 that the shift range is not "2 range pa", this indicates that the shift range is in the D range after all. The shift down control in step S14 and the lock up control in step S14 are performed in sequence.

As described above, steps S7, S8, S11, S1
When step S4 is completed, the process returns to step S2 and the above-described routine is repeated.

Shift-up control Subsequently, the shift-up control (normal control, fifth shift-up control) is performed.
Step S12) in the figure will be explained in detail with reference to FIG.

First, the gear position, that is, the position of the gear transmission mechanism 20 is read out. Next, based on the read gear position, it is determined in step S21 whether or not the vehicle is currently in the fourth gear. If it is not the fourth speed, the current throttle opening TH' is read in step S22, and data T SPI of the shift up map corresponding to the throttle opening is read in step S23. An example of this shift map is shown in FIG. Next, in step 324, the current turbine rotation speed TSP' is read, and this current turbine rotation speed TSP' is compared with the data TSPl of the shift-up map read above, and in step S25, the current turbine rotation speed TSP' is The set turbine rotation speed' indicated by the shift line Mfu1 in relation to the
It is determined whether the value is larger than rspt.

The current turbine rotation speed TSP' is the throttle opening TH
When the turbine speed is larger than the set turbine speed TSP1 in relation to the above, in step S26, the flag 1 for upshifting by one stage is read out, and it is set whether the read flag 1 is O or I, that is, it is in the reset state. determine whether the situation is Flag l is changed from 0 to 1 when a 1st gear upshift is executed. When flag l, which stores the 1st gear upshift state, is in the reset state, after flag 1 is set to 1 in step S27. , a shift-up is performed in step S87, and the one-stage shift-up control is completed.

In step S26, if the determination as to whether the flag l in the first stage shift door control system is 1 is 1, the control is completed as is.

Furthermore, even if the determination at the initial stage as to whether the vehicle is in the fourth gear is the fourth gear, the control is completed as is. Further, when it is determined in step S25 that the current turbine rotation speed TSP' is not larger than the set turbine rotation speed 'rspt indicated by the shift line Mfu1 in relation to the throttle opening TH, in step S29, "rspt" is set to "rspt", for example. Multiplying by 0.8, the new shift line M shown in broken line in Fig. 7 is obtained.
Set a new set turbine rotation speed TSF3 on fuz. Next, in step S30, the current turbine rotation speed T
It is determined whether or not SP' is larger than the set turbine rotation speed TSF3 indicated by the speed change number Mfu2, and if TSF3 is larger than TSP', flag 1 is reset in step S31 and the next Prepare for the cycle, reverse T
If TSF3 is not larger than SP', then shift down control is performed.

Shift down control The shift down control (step 513 in FIG. 5)
This is executed according to the downshift control subroutine shown in the figure. This downshift control is performed by first reading out the gear position, as in the case of upshift control. Next, based on the read gear position, it is determined in step S41 whether or not the vehicle is currently in the first gear. If it is not the first speed, the throttle opening degree TH is read in step S42, and then step 543
FIG. 9 shows an example of the shift down map in which data TSPl of the shift down map corresponding to the read throttle opening TH is read out. Then step 344
The current turbine rotation speed TSP' is read out, and this turbine rotation speed TSP' is compared with the set turbine rotation speed T SPI which is the data of the shift down map read out above, and the current turbine rotation speed TSP' is determined as the throttle opening TH The downshift shift line Mf cit
It is determined in step S45 whether or not the turbine rotation speed is smaller than the set turbine rotation speed TSPI shown in .

When the current turbine rotation speed TSP' is smaller than the set turbine rotation speed T spl , flag 2 for one-stage downshift is read out in step S46. Flag 2 is changed from O to 1 when the gear is downshifted by one gear.

Next, it is determined whether this flag 2 is 0 or 1, that is, whether it is in the reset state or in the set 9m. When flag 2 is in the reset state, flag 2 is set to 1 in step S47.
and downshifts by one step in step 348.
Completes 1st stage downshift control.

If it is determined in step S46 that the flag 2 is set, it is impossible to downshift, so the control is completed.

Further, in step 345, when it is determined that the current turbine rotation speed TSP' is not smaller than the set turbine rotation speed TSPI indicated by the first-stage downshift shift line Mfd1, a shift down map according to the current throttle opening is determined. is read out, and in step S49, the set turbine rotation speed T sp indicated by the shift line Mf di of this map is read out.
Multiply l by 110.8, for example, and create a new shift line Mf ct
2, a new set turbine rotation speed T sp2 is set. Next, in step 350, the current turbine rotation speed TS
When P' is smaller than the set turbine rotation speed TSF3 indicated by the shift line Mfd2, the control is completed, and when it is not smaller, flag 2 is reset to O in step S51, and the control is completed. After this, the system shifts to lock-up control.

In addition, in the shift-up speed change control and shift-down speed change control explained above, when a speed change is not performed,
The reason for creating hysteresis by multiplying the map's shift line by 0.8 or 110.8 to create a new shift line is to create hysteresis when the engine speed and turbine speed are at the critical speed for shifting, and gear shifts are performed frequently. This is to prevent chattering from occurring due to

Lockup Control Next, lockup control will be explained with reference to FIG. 10 (step 514 in FIG. 5).

First, in the lock-up control, after reading the current throttle opening TH' in step S61, in step 562, a lock-up OFF map, that is, a shift line Moff ( From the map showing the set turbine rotation speed TSP corresponding to the throttle opening (see Figure 11)
Read 1. Next, in step S63, the current turbine rotational speed TSP' is read, and in step S64, the read current turbine rotational speed TSP' is compared with the lock-up OFF map to determine the current turbine rotational speed TSP'.
It is determined whether SP' is larger than the setting - bin rotational speed TSPl indicated by the shift line MOFF. The current turbine rotation speed TSP' is the set turbine rotation speed TSP
If it is smaller than 1, lockup is released in step S65 and the process ends.

On the other hand, if the current turbine rotation speed TSP' is larger than the set turbine rotation speed T SPI, step 366
Then, from the lock-up ON map, that is, the map showing the shift line Man (see Figure 11) used for control to turn the lock-up into the ON (operating) state, another set turbine rotation corresponding to the throttle opening TH is determined. Number T SF
3 is read out, and then in step 367 it is determined whether the current turbine rotation speed TSP' is larger than the set turbine rotation speed TSF3. Then, T from TSP'
If SF3 is larger, lockup is activated in step 568 and the process ends, while TSP' is larger than T S
If F3 is not larger, the process ends.

Next, we will discuss the basic structure of the solenoid drive system as an electromagnetic means for speed change and the point of diagnosing its failure.
To explain with reference to FIG. 4, the first solenoid SLI is connected in series with the power supply transistor TR, and the control unit 200 is connected to the base of the power supply transistor TR.
When a low signal is output from the A terminal of the
(excitation). The B terminal of the control unit 200 is connected to the collector serving as the output A of the feed transistor TR to which the first renoid SLI is connected. Note that R in FIG. 14 is a resistor.

Therefore, when both the first solenoid SLI and the power supply transistor TR are normal and not disconnected or short-circuited, when a low signal is output from the A terminal, the power supply transistor TR becomes energized and the first solenoid SLI
turns on, and a high signal is output to the B terminal.

Conversely, when a low signal is output from the A terminal, the transistor T
R is cut off and the first solenoid SLI is turned off.
(demagnetization) and a low signal is output to the B terminal. In this manner, when both the power supply transistor TR and the first solenoid SLI are normal, one of the A terminal and the B terminal becomes high, and the other becomes low.

On the other hand, if one or both of the first solenoid SLI and the power supply transistor TR is faulty (broken or short-circuited), the A terminal and the B terminal will have a high-to-high or low-to-low relationship. Of course, the second solenoid SLI and the third solenoid SLl also have the same configuration as in FIG. 14.

In this way, for the drive system of each solenoid SLI, A
By looking at the high/low relationship between the terminal and the B terminal, it is possible to know whether or not the drive system of the solenoid SLI has failed (failure determination in step Sl).In addition, in the above-mentioned failure determination, It is impossible to know whether the solenoid is malfunctioning while it is ON or whether it is malfunctioning while it is OFF, but as will be described later, the present invention eliminates this particular problem. ing.

As described above, when it is determined in step 31 that the solenoid drive system is malfunctioning, auxiliary shift control is performed in step S16, which will be explained with reference to FIG. This auxiliary shift control is different from the main shift characteristic, and performs a two-speed shift based on a shift characteristic predetermined based on the throttle opening degree and vehicle speed.

First, in steps S71 and 72, the current throttle opening TH' and the current vehicle speed vsp' are sequentially read, and then in step S73, from the shift-up map (shift-up line) shown in FIG. It is determined whether the vehicle speed vsp corresponding to the current throttle opening TH' is smaller than the vehicle speed vsp' on the upshift line h,
If SP'> V SP+, step S75
As will be described later in , upshifting is performed using two normal solenoid drive systems.

If it is determined in step S74 that VSP'>VSPI does not hold, then in step S76, the vehicle speed VSP2 corresponding to the current throttle opening TH' is read from the shift down map (shift down line) shown in FIG. Next, in step 377, it is determined whether the current vehicle speed ■Sp is smaller than the vehicle speed ■SP2 on the shift down line, and if V SP ′<V SP+, the shift speed
At 78, a downshift is performed using two normal solenoid drive systems, as described below. Further, in step 377, if V SP '<V SP+ is not satisfied, the process ends (no shift).

Here, to explain in detail the shift in step S75.78 mentioned above, the relationship between the operating mode of the three solenoids SLI to SL3 as electromagnetic means for shifting and the gear position (or gear ratio) that can be achieved depending on this operating mode. are shown in Table 4 below. In addition, in this Table 4, operation mode ■.

- The phrases, f, and ■ are modes for each solenoid 5LI-3L3 to perform normal main shift control. In addition, the operating modes of the remaining two normal solenoids (corresponding to Table 1) are shown in Table 5 regarding the relationship between upshifts, downshifts, and gear positions (or gear ratios).

In Table 5, the gears without parentheses indicate when the faulty solenoid is OFF, and the gears with parentheses indicate when the faulty solenoid is ON.

From this Table 5, it is easily understood that even in the auxiliary shift control, it is possible to take two gears, a high gear and a low gear.

In other words, if the solenoid SLI remains OFF or F and is malfunctioning, the shift between 2nd and 3rd speeds, between 3rd and 4th speeds, and between lX4 and 4th speeds will be disabled. Shifts are made in response to the failed solenoid drive system. Also.

If the solenoid remains ON and is malfunctioning, shift between 1st and 3rd gear, shift between 1st gear and 2x4, shift between 1st and 3rd gear, Shifts are made in response to the failed solenoid drive system.

Although the embodiments have been described above, the present invention is not limited thereto, and includes, for example, the following cases.

■ There may be four or more electromagnetic means for speed change, and the larger the number of electromagnetic means for speed change, the more one electromagnetic means for speed change (
In the event that the drive system (drive system) fails, the degree of freedom in shifting gears can be increased using the remaining normal gear shifting electromagnetic means.
Further, it is also possible to set the number of gears during the auxiliary shift control to three or more gears.

(The main shift control characteristic may be determined based on the relationship between the throttle opening (engine load) and the vehicle speed, for example.

(4) The auxiliary shift control characteristics may be determined, for example, based on the relationship between the throttle opening (engine load) and the turbine rotation speed.

(4) Lockup may also be performed during auxiliary shift control (step S15 is eliminated).

(Effects of the Invention) As is clear from the above description, the present invention performs auxiliary shift control using a plurality of gears when one gearshift electromagnetic means fails, so when traveling in only one gear. It is less likely to cause problems in running compared to the above.

In addition, the above-mentioned auxiliary shift control can be performed regardless of whether the electromagnetic means for shifting itself fails while it is turned on or the electromagnetic means for shifting itself fails. This is extremely practical since there is no need to distinguish and detect faults in the parts that feed power to the faults in a particularly strict manner. Of course, if it is possible to detect a failure by turning ON or OFF the electromagnetic means for shifting, it becomes possible to set the auxiliary shifting control more preferably.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram of the present invention. FIG. 2 is a diagram showing a cross section of the mechanical part of the automatic transmission and its hydraulic circuit. FIG. 3 is an overall system diagram showing one embodiment of the present invention. FIG. 4 is a diagram showing an example of a speed change diagram. FIG. 5, FIG. 6, FIG. 8, FIG. 10, and FIG. 12 are flowcharts showing examples of control contents of the present invention. FIG. 7 is a diagram showing an example of a shift-up map. FIG. 9 is a diagram showing an example of a shift down map. FIG. 11 is a diagram showing an example of a lockup map. FIG. 13 is a diagram showing an example of an auxiliary shift diagram. FIG. 14 is a diagram showing a simplified example of a drive circuit for the electromagnetic means for speed change. l: Engine output shaft 20: Multi-stage gear transmission mechanism 200: Control unit EN: Engine SLI to SL3: Solenoid valve (electromagnetic means for speed change) Figure 7 Figure 8 Figure 1Q Figure

Claims (1)

[Claims] (1) a gear-type transmission mechanism interposed in an engine drive system; at least three or more gear-shifting electromagnetic means for controlling the supply of pressure fluid to a fluid-type actuator that performs a gear-shift operation of the gear-type transmission mechanism; a main shift control means that outputs a shift-up signal or a shift-down signal to each of the shift electromagnetic means to perform shift control of at least three or more gears based on a determined main shift characteristic; failure detection means for detecting a failure of the means; prohibition means for receiving an output from the failure detection means and prohibiting control by the main shift control means when the gear change electromagnetic means fails; and from the failure detection means. When the electromagnetic means for shifting fails, the remaining two or more normally operating electromagnetic means for shifting are used to control the shift at a plurality of gears less than the gears under the main shift control. A fault diagnosis control device for an automatic transmission, comprising: auxiliary shift control means for performing the following;