JP7112532B2 - Automatic transmission rotation sensor diagnostic device and diagnostic method - Google Patents

Description

The present invention relates to a rotation sensor diagnostic device and diagnostic method for an automatic transmission having a plurality of shift stages.

Conventionally, immediately after the engine is started, when the brake is operating and the selection of the driving range is detected by the inhibitor switch, when the turbine speed sensor detects the speed of rotation equal to or higher than a predetermined speed, the neutral speed is set. Determine that there is a failure. Further, there is known a failure detection device for an automatic transmission that includes a control unit that determines whether or not a vehicle speed sensor has a failure only when it is determined that there is no neutral failure (see, for example, Patent Document 1).

However, unless it is determined that there is no neutral failure, it is not possible to determine whether the vehicle speed sensor has failed. In other words, when there is an abnormality in rotation, it is impossible to determine whether it is an abnormality in the transmission system solenoid or a malfunction in the rotation sensor. For this reason, since only the rotation sensor abnormal region was defined as the rotation sensor abnormal region, there is a problem that the rotation sensor has low abnormality detectability.

SUMMARY OF THE INVENTION It is an object of the present invention to improve the ability to detect malfunction of a rotation sensor by diagnosing malfunction of the rotation sensor and malfunction of a shift system solenoid.

JP-A-11-280883

A rotation sensor diagnosis device for an automatic transmission according to the present invention includes a rotation sensor diagnostic controller for diagnosing whether a rotation sensor for detecting the number of rotations of a rotating element of an automatic transmission having a plurality of shift stages is normal or abnormal. Prepare.
The rotation sensor diagnostic controller compares the rotation speed detected by the rotation sensor with the theoretical rotation speed for each shift stage of the automatic transmission to detect an abnormality. If an abnormality is detected in a different gear stage among a plurality of gear stages of the automatic transmission, it is diagnosed as an abnormality in the rotation sensor.

In the case of a malfunction of the shift system solenoid, the shift speed in which the rotational relationship is lost is limited to the shift speed where the gear ratio is abnormal due to the involvement of the malfunction shift system solenoid. On the other hand, in the case of malfunction of the rotation sensor, the rotation relationship is broken in a plurality of different gear stages of the automatic transmission. Using this relationship, if an abnormality is detected in which the rotation relationship is broken at a different speed, the rotation sensor is diagnosed as having an abnormality. Therefore, the malfunction of the rotation sensor and the malfunction of the shift system solenoid can be separately diagnosed, and the abnormality detectability of the rotation sensor can be improved.

1 is an overall system diagram showing a drive system and a control system of an engine vehicle equipped with an automatic transmission to which the rotation sensor diagnostic device of the embodiment is applied; FIG. 4 is an engagement operation table showing the engagement state of each frictional engagement element for each gear stage in the automatic transmission of the embodiment; 4 is a shift map diagram showing an example of a shift map used for shift control in the automatic transmission of the embodiment; FIG. FIG. 4 is a diagram showing a normal region where a specific relationship is established and an abnormal region where a specific relationship is not established, with the detected rotation speed of a turbine rotation sensor as the ordinate and the theoretical turbine rotation speed as the abscissa. FIG. 4 is a relational diagram showing a turbine rotation sensor capable of diagnosing at each speed stage by separating gear ratio abnormality in a first turbine rotation sensor and a second turbine rotation sensor; FIG. 10 is an abnormality judgment table showing the interrelationship between combinations of establishment/non-establishment of three abnormality judgment formulas, normality/abnormality combinations of three abnormal rotation sensors, and normality/abnormality of wheel speed signals; FIG. 4 is a flow chart showing the flow of rotation sensor rationality diagnosis processing executed by a rotation sensor diagnosis section of the automatic transmission controller of the embodiment; FIG. 4 is a comparison diagram showing area divisions before and after change of the normal area and the abnormal area of the automatic transmission; 5 is a time chart showing an example of a case where a relational expression is not established and an abnormality in a rotation sensor is determined when the gear stage is upshifted from 1st gear to 2nd gear to 3rd gear.

BEST MODE FOR CARRYING OUT THE INVENTION A best mode for realizing a rotation sensor diagnostic apparatus for an automatic transmission according to the present invention will be described below based on an embodiment shown in the drawings.

The rotation sensor diagnostic device of the embodiment is applied to an engine vehicle (an example of a vehicle) equipped with a stepped automatic transmission having seven forward speeds and one reverse speed. The configuration of the embodiment will be described below by dividing it into "overall system configuration", "automatic transmission power train configuration", "automatic transmission shift control configuration", and "rotation sensor rationality diagnosis processing configuration".

[Overall system configuration]
FIG. 1 shows the drive system and control system of an engine vehicle equipped with an automatic transmission to which the control device of the embodiment is applied.

As shown in FIG. 1, the drive system of the engine vehicle includes an engine Eng and an automatic transmission AT.

The automatic transmission AT is a stepped automatic transmission called a step AT with seven forward speeds and one reverse speed. The driving force of the engine Eng is input to the automatic transmission AT from the input shaft Input via the torque converter TC having the lockup clutch LU/C. The rotational speed is changed by four planetary gears and seven frictional engagement elements, and output from an output shaft Output to driving wheels (not shown). Further, an oil pump OP is provided coaxially with the pump impeller of the torque converter TC, and is rotationally driven by the driving force of the engine Eng to pressurize the oil.

As shown in FIG. 1, the control system of the engine vehicle includes an engine controller 10 (ECU), an automatic transmission controller 20 (ATCU), and a control valve unit 30 (CVU). The engine controller 10 and the automatic transmission controller 20 are connected via a CAN communication line 40 and share sensor information, control information, and the like by two-way communication.

The engine controller 10 mainly controls the driving state of the engine Eng. Connected to the engine controller 10 are an accelerator opening sensor 1 that detects an accelerator opening APO representing the accelerator pedal operation amount of the driver, and an engine rotation sensor 2 that detects the engine rotation speed Ne. The engine controller 10 controls the engine speed and engine torque by adjusting the fuel injection amount and throttle opening based on the engine speed Ne, accelerator opening APO and vehicle speed VSP.

The automatic transmission controller 20 mainly performs shift control of the automatic transmission AT. The automatic transmission controller 20 is connected to a first turbine rotation sensor 3 that detects the rotation speed of the first carrier PC1 and a second turbine rotation sensor 4 that detects the rotation speed of the first ring gear R1. Further, an output rotation sensor 5 for detecting the output rotation speed, an inhibitor switch 6 for detecting the range position selected by the driver's select lever, and a wheel speed sensor 7 for detecting the wheel speed are connected. there is The automatic transmission controller 20 has normality/abnormality detection of the first turbine rotation sensor 3, the second turbine rotation sensor 4, and the output rotation sensor 5 based on the combined state of establishment/non-establishment of the three abnormality determination formulas. has a rotation sensor diagnosis unit 20a (rotation sensor diagnosis controller) for diagnosing rationality.

The control valve unit 30 includes solenoid valves and oil passages that control engagement/disengagement of each friction engagement element based on a control command from the automatic transmission controller 20 .

[Power train configuration of automatic transmission]
The powertrain configuration of the automatic transmission AT will be described below with reference to FIG.
The automatic transmission AT includes, as transmission gears, a first planetary gear set GS1 consisting of a first planetary gear G1 and a second planetary gear G2, and a third planetary gear, arranged in order from the input shaft Input side to the output shaft Output side. A second planetary gear set GS2 is arranged with G3 and a fourth planetary gear G4. As hydraulically controlled friction engagement elements, a first clutch C1, a second clutch C2, a third clutch C3, a first brake B1, a second brake B2, a third brake B3, and a fourth brake B4 are arranged. . Furthermore, a first one-way clutch F1 and a second one-way clutch F2 are arranged as one-way clutches that are mechanically engaged/idled.

The first planetary gear G1 is a single pinion type planetary gear having a first sun gear S1, a first ring gear R1, and a first carrier PC1 supporting a first pinion P1 meshing with both gears S1 and R1.

The second planetary gear G2 is a single pinion type planetary gear having a second sun gear S2, a second ring gear R2, and a second carrier PC2 supporting a second pinion P2 meshing with both gears S2 and R2.

The third planetary gear G3 is a single pinion planetary gear having a third sun gear S3, a third ring gear R3, and a third carrier PC3 supporting a third pinion P3 meshing with both gears S3 and R3.

The fourth planetary gear G4 is a single pinion type planetary gear having a fourth sun gear S4, a fourth ring gear R4, and a fourth carrier PC4 supporting a fourth pinion P4 meshing with both gears S4 and R4.

The input shaft Input is connected to the second ring gear R2, and receives rotational driving force from the engine Eng via a torque converter TC and the like. The output shaft Output is connected to the third carrier PC3, and transmits the output rotational driving force to the driving wheels via a final gear or the like.

The first ring gear R1, the second carrier PC2 and the fourth ring gear R4 are integrally connected by a first connecting member M1. The third ring gear R3 and the fourth carrier PC4 are integrally connected by a second connecting member M2. The first sun gear S1 and the second sun gear S2 are integrally connected by a third connecting member M3.

The first planetary gear set GS1 is configured to have four rotating elements by connecting the first planetary gear G1 and the second planetary gear G2 with the first connecting member M1 and the third connecting member M3. . Also, the second planetary gear set GS2 is configured to have five rotating elements by connecting the third planetary gear G3 and the fourth planetary gear G4 with the second connecting member M2.

In the first planetary gearset GS1, torque is input from the input shaft Input to the second ring gear R2, and the input torque is output to the second planetary gearset GS2 via the first connecting member M1. In the second planetary gear set GS2, torque is input directly from the input shaft Input to the second connecting member M2 and is also input to the fourth ring gear R4 via the first connecting member M1, and the input torque is transferred to the third carrier PC3. is output from to the output shaft Output.

The first clutch C1 (input clutch I/C) is a clutch that selectively connects and disconnects the input shaft Input and the second connecting member M2. The second clutch C2 (direct clutch D/C) is a clutch that selectively connects and disconnects the fourth sun gear S4 and the fourth carrier PC4. The third clutch C3 (H&LSR clutch H&LR/C) is a clutch that selectively connects and disconnects the third sun gear S3 and the fourth sun gear S4.

The second one-way clutch F2 is arranged between the third sun gear S3 and the fourth sun gear S4. As a result, when the third clutch C3 is released and the rotational speed of the fourth sun gear S4 is higher than that of the third sun gear S3, the third sun gear S3 and the fourth sun gear S4 generate independent rotational speeds. Therefore, the third planetary gear G3 and the fourth planetary gear G4 are connected via the second connecting member M2, and each planetary gear achieves an independent gear ratio.

The first brake B1 (front brake F/B) is a brake that selectively stops the rotation of the first carrier PC1 with respect to the transmission case Case. Also, the first one-way clutch F1 is arranged in parallel with the first brake B1. The second brake B2 (low brake LOW/B) is a brake that selectively stops the rotation of the third sun gear S3 with respect to the transmission case Case. The third brake B3 (2346 brake 2-3-4-6/B) selectively stops the rotation of the third connecting member M3 that connects the first sun gear S1 and the second sun gear S2 with respect to the transmission case Case. is. The fourth brake B4 (reverse brake REV/B) is a brake that selectively stops rotation of the fourth carrier PC4 with respect to the transmission case Case.

[Shift Control Configuration of Automatic Transmission]
FIG. 2 is an engagement operation table showing the engagement state of each frictional engagement element for each gear stage in the automatic transmission AT of the embodiment. In FIG. 2, the ○ mark indicates that the frictional engagement element is in the engaged state, the (○) mark indicates that the frictional engagement element is in the engaged state during coasting when the engine brake is operated, and the no mark indicates that the frictional engagement element is in the engaged state. Indicates that the friction engagement element is in the released state.

When upshifting or downshifting between adjacent gears by the automatic transmission AT, the one engaged frictional engagement element is released and the released one frictional engagement element is engaged. I do. As described below, seven forward speeds and one reverse speed can be realized by this replacement speed change.

That is, in the "first gear" during driving by depression of the accelerator, the first one-way clutch F1 and the second one-way clutch F2 are engaged while the second brake B2 is in the engaged state. In the "1st gear" when coasting by releasing the accelerator pedal (during engine braking), the first one-way clutch F1 and the second one-way clutch F2 are idling, so that the third clutch C3, the first brake B1 and the second brake B2 are engaged. It will be in a closed state.

In the "2nd speed stage" during driving by stepping on the accelerator, the second one-way clutch F2 is engaged while the second brake B2 and the third brake B3 are engaged. In "2nd speed" when coasting (during engine braking) by releasing the accelerator pedal, the second one-way clutch F2 idles, so that the third clutch C3, the second brake B2, and the third brake B3 are engaged.

In the "3rd gear", the second brake B2, the third brake B3, and the second clutch C2 are engaged regardless of whether the vehicle is driving or coasting.
In the "fourth gear", the third brake B3, the second clutch C2, and the third clutch C3 are engaged regardless of whether the vehicle is driving or coasting.
In the "fifth gear", the first clutch C1, the second clutch C2, and the third clutch C3 are engaged regardless of whether the vehicle is driving or coasting.
In the "sixth gear", the third brake B3, the first clutch C1, and the third clutch C3 are engaged regardless of whether the vehicle is driving or coasting.
In the "7th gear", the first brake B1, the first clutch C1 and the third clutch C3 are engaged regardless of whether the vehicle is driving or coasting.

In the "reverse gear" during driving by stepping on the accelerator, the first one-way clutch F1 and the second one-way clutch F2 are engaged while the fourth brake B4 is engaged. In the "reverse gear" when coasting by releasing the accelerator pedal (during engine braking), the first one-way clutch F1 and the second one-way clutch F2 are idling, so that the third clutch C3, the first brake B1 and the fourth brake B4 are engaged. It will be in a closed state.

FIG. 3 is a shift map diagram showing a shift map used for shift control in the automatic transmission AT of the embodiment. The shift map shown in FIG. 3 is stored and set in advance in the memory of the automatic transmission controller 20. The solid line indicates the upshift line, and the dotted line indicates the downshift line.

When the D range is selected, the operating point (VSP, APO) determined based on the vehicle speed VSP from the output rotation sensor 5 (=vehicle speed sensor) and the accelerator opening APO from the accelerator opening sensor 1 exists on the shift map. to search for a position. Then, if the operating point (VSP, APO) does not move, or if the operating point (VSP, APO) moves but remains within one gear range on the shift map of FIG. Keep the gear as it is.

On the other hand, when the operating point (VSP, APO) moves and crosses the up-shift line on the shift map in FIG. An up-shift command to the shift stage indicated by the area where the point (VSP, APO) exists is output. Also, when the operating point (VSP, APO) moves and crosses the downshift line on the shift map in FIG. A downshift command to the shift stage indicated by the area where the point (VSP, APO) exists is output.

[Configuration of Rotation Sensor Diagnosis Unit]
The rotation sensor diagnosing unit 20a selects the "first turbine rotation sensor 3", the "second turbine rotation sensor 4", and the "output rotation sensor 5" for detecting the rotation speed of the rotating elements of the automatic transmission AT for rationality diagnosis. and the rotation sensor. Here, "rationality diagnosis" means diagnosing normality/abnormality of the rotation sensors 3, 4, and 5 by a rational method using a specific relationship between the detected rotation speed and the theoretical rotation speed. .

In the rationality diagnosis of the rotation sensors 3, 4, 5 in the rotation sensor diagnosis unit 20a, the rotation speed detected by the rotation sensors 3, 4, 5 is compared with the theoretical rotation speed for each shift stage of the automatic transmission AT. to detect anomalies. Specifically, the normality/abnormality of the rotation sensors 3, 4, and 5 is detected based on the combined state of establishment/non-establishment of the first abnormality determination formula, the second abnormality determination formula, and the third abnormality determination formula. do.

For example, as shown in FIG. 4, the vertical axis represents the detected rotation speed of the turbine rotation sensor, and the horizontal axis represents the theoretical turbine rotation speed (=output rotation speed No.times.gear ratio α). At this time, two values that establish a specific relationship are compared, and if the two values are within a predetermined error range, it can be detected as normal, and if they are out of the predetermined error range, it can be detected as abnormal.

As shown in FIG. 5, for each gear stage of the automatic transmission AT, as for the first turbine rotation sensor 3, it is determined that the gear ratio is abnormal in the first, second, sixth, and seventh gears. can be divided. As for the second turbine rotation sensor 4, as shown in FIG. 5, it is possible to determine whether the gear ratio is abnormal at the 2nd, 3rd, 4th, 5th, and 6th speeds. On the other hand, the "rotation sensor" is a combination of the first turbine rotation sensor 3, the second turbine rotation sensor 4, and the output rotation sensor 5. Therefore, the rationality diagnosis of the rotation sensors 3, 4 and 5 can be performed at any one of the 1st to 7th speeds, which are all the speeds of the automatic transmission AT.

As shown in FIG. 6, the first abnormality determination formula is given by |Nt1−No×α1|>β1 using the first turbine speed Nt1, the output speed No, and the gear ratio α1. As shown in FIG. 6, the second abnormality determination formula is given by |Nt2−No×α2|>β2 using the second turbine speed Nt2, the output speed No, and the gear ratio α2. As shown in FIG. 6, the third abnormality determination formula is given by |Nt2−Novsp2×α2|>β3 using the second turbine speed Nt2, the wheel speed Novsp2, and the gear ratio α2.

Next, the rotation sensor diagnosis unit 20a diagnoses that any one of the rotation sensors 3, 4, and 5 is abnormal when an abnormality is detected in a different gear stage among the plurality of gear stages of the automatic transmission AT. . Specifically, as the number of times of abnormality detection of the rotation sensors 3, 4, and 5, the number of times equal to or greater than a threshold value (for example, 4 times) based on the minimum experience frequency value in which the abnormality detection is experienced at two or more different gear stages. Continuous experience confirms the diagnosis that the rotation sensors 3, 4, 5 are abnormal.

This is because, in the case of gear ratio abnormality, the specific relationship is not established only in limited shift speeds. However, the fact that an abnormality is detected in a different gear position means that the malfunction of the rotation sensors 3, 4, and 5 can be identified by excluding the gear ratio abnormality due to the malfunction of the shift system solenoid.

Further, the reason why the threshold value is set to the experience count value in the minimum range is that when a malfunction of the rotation sensors 3, 4, 5 occurs, the rotation sensors 3, 4, 4, 5 are detected at an earlier timing than the detection timing of the gear ratio/neutral abnormality. This is due to the desire to confirm the diagnosis that 5 is abnormal. If the gear ratio/neutral abnormality is detected first, the abnormality diagnosis of the rotation sensors 3, 4 and 5 is prohibited in order to prevent erroneous detection.

[Configuration of rotation sensor rationality diagnosis processing]
FIG. 7 shows the flow of rationality diagnosis processing for the rotation sensors 3, 4, 5 executed by the rotation sensor diagnosis section 20a of the automatic transmission controller 20 of the embodiment. Each step in FIG. 7 showing the rationality diagnosis processing configuration of the rotation sensors 3, 4, and 5 will be described below. Note that the process of FIG. 7 is repeatedly executed in a predetermined control period, for example, with the ignition ON as a start condition and the ignition OFF as an end condition. In the flowchart of FIG. 7, "A" indicates an abnormal state continuation timer, "B" indicates an anomaly detection counter, "C" indicates a normal state continuation timer, and "D" indicates a normal detection counter.

In step S1, following the start, it is determined whether or not a condition for prohibiting rotation sensor rationality diagnosis has been established. If YES (prohibition condition satisfied), the process proceeds to step S2, and if NO (prohibition condition not satisfied), the process proceeds to step S3.

Here, the prohibited conditions for the rotation sensor rationality diagnosis are:
(a) When gear ratio/neutral error is detected
(b) When interlock is detected
(c) UDS over-rotation error detection
(d) Low/B function error detection
(e) When an electrical abnormality is detected in the transmission SOL
(f) This refers to when the existing rotation sensor disconnection is detected.

In step S2, following determination of YES in S1, NO in S3, or NO in S11, the abnormal state continuation timer A and the normal state continuation timer C are reset, and the abnormality detection counter B and Keep the previous value of the normality detection counter D, and proceed to the end.

In step S3, it is determined whether or not the condition for permitting the rotation sensor rationality diagnosis has been satisfied, following the determination in step S1 that the prohibition condition is not satisfied. If YES (permission condition satisfied), the process proceeds to step S4, and if NO (permission condition not satisfied), the process proceeds to step S2.

Here, the conditions for permitting rotation sensor rationality diagnosis are:
(g) Steady shift stage (not shifting gears)
(h) Selected range position is driving range (other than N, R, P ranges)
(i) During engine operation (not during idle stop or fuel cut)
(j) Throttle opening is greater than or equal to a predetermined opening when the shift stage is 1st and 2nd. Permission condition (j) is a condition for ensuring drive engagement without idling of the one-way clutches F1 and F2 when the gear stage is 1st or 2nd gear.

In step S4, following the determination in step S3 that the permission condition is satisfied, it is determined whether or not there is an abnormal combination. If YES (abnormal combination), go to step S5, and if NO (non-abnormal combination), go to step S11.

Here, the "combination of abnormalities in the first turbine rotation sensor 3" means, as shown in FIG. is not established. The "combination of abnormalities in the second turbine rotation sensor 4" means, as shown in FIG. It refers to the combination state by As shown in FIG. 6, the "combination of abnormalities in the output rotation sensor 5" means that the first abnormality determination formula is satisfied, the second abnormality determination formula is satisfied, and the third abnormality determination formula is not satisfied. Refers to the combined state. However, the condition is that the wheel speed signal from the wheel speed sensor 7 is normal.

In step S5, following the determination in step S4 that there is a combination of abnormalities, the value of the abnormal state continuation timer A while maintaining the abnormal combination state becomes a value after a set time (for example, about 1 sec) has elapsed. determine whether or not If YES (A≧set time), go to step S7, and if NO (A<set time), go to step S6.

In step S6, following the determination in step S5 that A<set time, the abnormal state continuation timer A is counted, the normal state continuation timer C is reset, and the previous values of the abnormality detection counter B and the normal detection counter D are set. Keep and proceed to the end.

In step S7, following the determination in step S5 that A≧set time, the abnormality detection counter B is incremented by 1 for each shift stage, the normality detection counter D is all reset, and the abnormality continuation timer A and normal state continuation are performed. The previous value of timer C is kept, and the process proceeds to step S8.
That is, if the set time or longer elapses while the abnormal combination state is maintained, the rotation sensor is detected to be abnormal, and the abnormality detection counter B of the gear is incremented by one.

In step S8, following the rotation sensor abnormality detection process in S7, the abnormality detection counter B is counted by 1 or more at different gear stages (a plurality of gear stages), and the total value is a threshold value (for example, 4 times) or more. determine whether there is If YES (B (total)≧4), go to step S10, and if NO (B (total)<4), go to step S9.

Here, the "threshold value" is set to the minimum experience count value in which abnormality detection is experienced at two or more different gear stages. Specifically, there are two conflicting demands: the false detection prevention request that "anomaly is confirmed when an anomaly is experienced multiple times" and the early diagnosis requirement that "the anomaly should be experienced at multiple gear stages within the FTP cycle". , both are established, so the "threshold" is set to "4 times" in the embodiment. The "FTP cycle" is one of the driving cycles of automobiles, and refers to the driving cycle in the American FTP mode, which is used to measure exhaust gas under normal temperature and low temperature environments when driving in urban areas.

In step S9, following the judgment in S8 that B (total)<4, the previous values of the abnormal state continuation timer A, the abnormality detection counter B, the normal state continuation timer C, and the normal detection counter D are kept, and the end proceed to

In step S10, following the determination in step S8 that B (total)≧4, the abnormality diagnosis of the rotation sensors 3, 4, and 5 is confirmed, and the abnormal state continuation timer A, the abnormality detection counter B, and the normal state continuation timer A are set. Keep the previous values of timer C and normality detection counter D, and proceed to the end.

Here, even if the abnormality diagnosis of the rotation sensors 3, 4, 5 is confirmed, the abnormality processing by fail-safe or limp-home is not performed, and the failure display lamp is simply turned on and the failure code is stored. Then, the gear ratio/neutral abnormality detection of the automatic transmission AT, which is executed in conjunction with the rationality abnormality diagnosis of the rotation sensors 3, 4, and 5, is continued.

In step S11, it is determined whether or not the combination is normal following the determination in step S4 that the combination is not abnormal. If YES (normal combination), go to step S12, and if NO (other combination), go to step S2.

Here, "normal combination" means that the wheel speed signal from the wheel speed sensor 7 is normal as shown in FIG. A combined state in which the determination formula is not satisfied and the third abnormality determination formula is not satisfied. "Other combinations" means that, as shown in FIG. 6, when the wheel speed signal from the wheel speed sensor 7 is abnormal by self-diagnosis, the first abnormality judgment formula is not established, and the second abnormality judgment formula is not established and the third abnormality determination formula is established.

In step S12, following the judgment in step S11 that the combination is normal, the value of the normal state continuation timer C while maintaining the normal combination state becomes a value after a set time (for example, about 1 sec) has elapsed. determine whether or not If YES (C≧set time), go to step S14. If NO (C<set time), go to step S13.

In step S13, after determining that C<set time in S12, the normal state continuation timer C is counted, the abnormal state continuation timer A is reset, and the previous values of the abnormality detection counter B and the normal detection counter D are set. Keep and proceed to the end.

In step S14, following the determination in S12 that C≧set time, the normality detection counter D is incremented by 1, the abnormality detection counter B is all reset, and the abnormal state continuation timer A and the normal state continuation timer C Keep the value and proceed to step S15.
That is, when a set time or longer elapses while the normal combination state is maintained, it is detected that the rotation sensor is normal, and the normality detection counter D is incremented by one.

In step S15, following the rotation sensor normality detection process in S14, it is determined whether or not the normality detection counter D is equal to or greater than a threshold value (for example, 4 times). If YES (D≧4), the process proceeds to step S17, and if NO (D<4), the process proceeds to step S16.

Here, the "threshold value" is set to the minimum experience count value in which normal detection is experienced at two or more different gear stages.

In step S16, following the judgment in S15 that D<4, the previous values of the abnormal state continuation timer A, the abnormality detection counter B, the normal state continuation timer C, and the normal detection counter D are kept, and the process proceeds to END.

In step S17, following the determination in S15 that D≧4, the normal diagnosis of the rotation sensors 3, 4, and 5 is confirmed, and the abnormal state continuation timer A, the abnormality detection counter B, the normal state continuation timer C, Keep the previous value of the normality detection counter D, and proceed to the end.

Next, "problems of the background art and measures for solving the problems" will be explained. Then, the action of the embodiment will be described separately for "rotation sensor rationality diagnosis processing action" and "rotation sensor abnormality diagnosis confirming action".

[Problem of background technology and solution to the problem]
As background technology for abnormality diagnosis in automatic transmissions, as shown in the abnormality/normality diagnosis outline diagram before change in FIG. , and has a gear ratio/neutral abnormality detection region G as a part of the gear ratio deviation region F. The gear ratio/neutral abnormality detection area G includes both the malfunction of the transmission system solenoid and the malfunction of the rotation sensor, and as a result, the gear ratio abnormality and the neutral abnormality are detected. Then, when the gear ratio/neutral abnormality detection area is reached, fail-safe control is performed by fixing 1st gear, limiting 1-2 shifting, limiting 1-2-3 shifting, limiting 2-3-4 shifting, and limiting 4-5-6 shifting. or running limp home control.

However, there is a demand to perform rotation sensor abnormality diagnosis to determine whether the rotation sensor installed in the automatic transmission is malfunctioning. To satisfy this requirement,
1) It is necessary to construct a diagnosis that can be detected in the FTP cycle and that can ensure the frequency of diagnosis.
2) It is necessary to construct an appropriate fail-safe in the rotation sensor rationality diagnosis.
There is a problem to be solved.

In order to solve the above problem, the inventors of the present invention focused on separating out only the malfunction of the rotation sensor from the gear ratio/neutral malfunction detection area G. That is, as shown in the abnormality/normality diagnosis outline diagram after the change in FIG. 8, the rotation sensor rationality failure detection area H is further separated from the gear ratio/neutral abnormality detection area G before the change. Then, the problem 1) was realized by the rotation sensor rationality failure detection area H, and the problem 2) was realized by leaving the gear ratio/neutral abnormality detection area G.

As a solution to the problem, the automatic transmission AT having multiple speeds and the rotation sensors 3, 4, 5 that detect the rotation speed of the rotating elements of the automatic transmission AT are normal or abnormal. and a sensor diagnosis unit 20a. In this rotation sensor diagnostic device for the automatic transmission AT, the rotation sensor diagnostic unit 20a compares the rotation speed detected by the rotation sensors 3, 4, and 5 with the theoretical rotation speed for each shift stage of the automatic transmission AT. to detect anomalies. If an abnormality is detected in a different gear stage among a plurality of gear stages of the automatic transmission AT, a measure is adopted to diagnose that the rotation sensors 3, 4, and 5 are abnormal.

First, in the case of a malfunction of the shift system solenoid, the shift stage where the rotational relationship is lost is limited to the shift stage where the gear ratio is abnormal due to the malfunction of the shift system solenoid. On the other hand, if the rotation sensors 3, 4, 5 are malfunctioning, the rotation relationship is broken in a plurality of different gear stages of the automatic transmission AT. Using this relationship, when an abnormality is detected in which the rotational relationship is broken at different speeds, it is diagnosed that the rotation sensors 3, 4, 5 are abnormal. Therefore, the abnormality detectability of the rotation sensors 3, 4, 5 can be improved by diagnosing the malfunction of the rotation sensors 3, 4, 5 and the malfunction of the shift system solenoid separately.

[Rotation sensor rationality diagnosis processing action]
The rationality diagnosis processing action of the rotation sensors 3, 4 and 5 will be described based on the flowchart shown in FIG.

First, if the prohibition condition is not satisfied and the permission condition is satisfied, and the combination is abnormal, S1→S3→S4→S5→S6 until the value of the abnormal state continuation timer A does not reach the set time. →The flow to the end is repeated. At this time, before the value of the abnormal state continuation timer A reaches the set time, for example, when the next shift is executed and the permission condition is no longer satisfied, the process proceeds from S1 → S3 → S2 → end, and the abnormal condition continues. The value of state duration timer A is reset.

On the other hand, until the value of the abnormal state continuation timer A reaches the set time, when the combination of abnormalities continues without the prohibition condition being satisfied or the permitting condition being unsatisfied, from S5 to S7→S8→S9. → Proceed to the end. In S7, the abnormality detection counter B is incremented by 1, and in S9, the previous values of A to D are kept.

For example, assume that a different gear stage is selected after the permission condition is no longer satisfied due to the execution of the next gear shift. After changing the gear stage, if the prohibition condition is not satisfied and the permission condition is satisfied, and the combination is abnormal, S1→S3→S4 until the value of the abnormal state continuation timer A does not reach the set time. →S5→S6→End is repeated. Then, until the value of the abnormal state continuation timer A reaches the set time, when the combination of abnormalities continues without the prohibition condition being satisfied or the permitting condition being unsatisfied, from S5 to S7→S8→S9. → Proceed to the end. In S7, the abnormality detection counter B is further incremented by 1, and in the next S9, the previous values of A to D are kept.

Then, the situation in which the abnormality detection counter B is incremented by 1 is repeated, and when the total value of the abnormality detection counter B reaches four times, the process proceeds from S7 to S8→S10→End. At S10, the abnormality diagnosis of the rotation sensors 3, 4 and 5 is confirmed, and the previous values of A to D are kept. However, even if the abnormality diagnosis of the rotation sensors 3, 4, 5 is confirmed, the abnormality processing by fail-safe or limp-home is not performed, and the failure display lamp is simply turned on and the failure code is stored. Then, the gear ratio/neutral abnormality detection of the automatic transmission AT, which is executed in conjunction with the rationality abnormality diagnosis of the rotation sensors 3, 4, and 5, is continued.

On the other hand, it is assumed that a normal combination is determined while the abnormality detection counter B is counting up. In this case, if the prohibition condition is not satisfied and the permission condition is satisfied, and the combination is normal, S1 → S3 → S4 → S11 → until the value of the normal state continuation timer C does not reach the set time. The flow of S12→S13→End is repeated. Then, until the value of the normal state continuation timer C reaches the set time, neither the prohibition condition is satisfied nor the permission condition is not satisfied, and the normal combination continues, from S12 to S14→S15→S16. → Proceed to the end. In S14, the normality detection counter D is incremented by 1, the abnormality detection counter B is all reset, and in the next S16, the previous values of A to D are kept.

Then, the state in which the normality detection counter D is incremented by 1 is repeated, and when the normality detection counter D reaches 4 times, the process proceeds from S14 to S15→S17→END. In S17, the normal diagnosis of the rotation sensors 3, 4 and 5 is confirmed, and the previous values of A to D are kept.

In addition, if the prohibition condition is established due to the gear ratio/neutral abnormality detection etc. before the normal diagnosis or the abnormality diagnosis of the rotation sensors 3, 4, 5 is confirmed, the flow of S1 → S2 → end is repeated, and the rotation sensor Rationality diagnosis processing of 3, 4 and 5 is prohibited. Then, based on gear ratio/neutral abnormality detection, interlock detection, rotation sensor disconnection detection, etc., abnormal processing (fail safe, limp home) is activated.

[Abnormal Diagnosis Confirmation Action of Rotation Sensor]
Next, an example of confirming the abnormality diagnosis of the rotation sensors 3, 4, 5 will be described based on the time chart shown in FIG.

From time t1 to time t3, the vehicle is in the 1st speed state in which the diagnosis permission flag is set to permission. At this time, when the abnormal state continues and the abnormality detection time (for example, 1 sec) is reached at time t2, the abnormality detection counter B counts once.

After time t3, until time t4, during the upshift from 1st speed to 2nd speed, the diagnosis permission flag is set to a prohibited section. Then, from time t4 to time t5, the vehicle is in the 2nd speed state in which the diagnosis permission flag is set to permission. At this time, the abnormal state continues, but the abnormality detection counter B does not count unless the abnormality detection time (for example, 1 sec) is reached at time t5.

After time t5, until time t6, during the upshift from 2nd speed to 3rd speed, the diagnosis permission flag is set to a prohibited section. After time t6, the 3rd speed state in which the diagnosis permission flag is set to permission is maintained. At this time, when the abnormal state continues and the abnormality detection time (for example, 1 sec) is reached from time t6 to time t7, the abnormality detection counter B counts twice. When the abnormality detection time (for example, 1 sec) is reached from time t7 to time t8, the abnormality detection counter B counts three times. Further, when the abnormality detection time (for example, 1 sec) is reached from time t8 to time t9, the abnormality detection counter B counts four times.

In this way, the 1st speed (experienced 1 time of error detection) and the 3rd speed (experienced 3 times of error detection), which are different gear stages of the automatic transmission AT, completed a total of 4 times of error detection experience. When the time t9 comes, the abnormality diagnosis of the rotation sensors 3, 4 and 5 is confirmed.

As described above, the rotation sensor diagnostic device for the automatic transmission AT according to the embodiment has the following effects.

(1) Rotation sensor diagnosis controller (rotation sensor diagnostic unit) that diagnoses whether the rotation sensors 3, 4, 5 that detect the rotation speed of the rotating elements of the automatic transmission AT, which has a plurality of gears, are normal or abnormal. 20a) in a rotation sensor diagnostic device for an automatic transmission AT,
The rotation sensor diagnosis controller (rotation sensor diagnosis unit 20a)
Detects an abnormality by comparing the rotation speed detected by the rotation sensors 3, 4, and 5 with the theoretical rotation speed for each shift stage of the automatic transmission AT,
If an abnormality is detected in a different gear stage among a plurality of gear stages of the automatic transmission AT, it is diagnosed that the rotation sensors 3, 4 and 5 are abnormal.
Therefore, the abnormality detectability of the rotation sensors 3, 4, 5 can be improved by diagnosing the malfunction of the rotation sensors 3, 4, 5 and the malfunction of the shift system solenoid separately.

(2) As rotation sensors for the automatic transmission AT, a first turbine rotation sensor 3 that detects the first turbine rotation speed Nt1, a second turbine rotation sensor 4 that detects the second turbine rotation speed Nt2, and an output rotation speed and an output rotation sensor 5 that detects No,
The rotation sensor diagnosis controller (rotation sensor diagnosis unit 20a)
The first abnormality determination formula using the first turbine speed Nt1, the output speed No, and the gear ratio α1, and the second abnormality using the second turbine speed Nt2, the output speed No, and the gear ratio α2 Using the determination formula and the third abnormality determination formula using the second turbine rotation speed Nt2, the wheel speed Novsp2, and the gear ratio α2,
The normality/abnormality of the rotation sensors 3, 4, 5 is detected from the combined state of establishment/non-establishment of the first abnormality determination formula, the second abnormality determination formula, and the third abnormality determination formula.
Therefore, the normality/abnormality of the first turbine rotation sensor 3, the second turbine rotation sensor 4, and the output rotation sensor 5 of the automatic transmission AT are detected by the combined state of establishment/non-establishment of the three abnormality determination formulas. can do.

(3) The rotation sensor diagnosis controller (rotation sensor diagnosis unit 20a) maintains the abnormal combination state by establishment/non-establishment of the first abnormality judgment expression, the second abnormality judgment expression, and the third abnormality judgment expression. When the set time or more has passed, the rotation sensors 3, 4 and 5 are detected as abnormal.
For this reason, when the rotation sensors 3, 4 and 5 are detected to be abnormal, the case where the combined state of the establishment/non-establishment of the three abnormality determination formulas is instantaneously established is excluded, and the rotation sensors 3, 4 and 5 are abnormal. A certain thing can be detected with high accuracy.

(4) The rotation sensor diagnosis controller (rotation sensor diagnosis unit 20a) determines the number of times of abnormality detection of the rotation sensors 3, 4, and 5 based on the minimum empirical number of times that an abnormality is detected at two or more different gear stages. If the number of times equal to or greater than the threshold value is experienced continuously, the diagnosis that the rotation sensors 3, 4 and 5 are abnormal is confirmed.
Therefore, the time required from the occurrence of an abnormality in the rotation sensors 3, 4, 5 to the determination of the abnormality in the rotation sensors 3, 4, 5 can be reduced to the minimum time required to prevent erroneous detection. .

(5) The rotation sensor diagnosis controller (rotation sensor diagnosis unit 20a) determines the first abnormality determination formula, the second abnormality determination formula, and the third abnormality determination formula when the number of times of abnormality detection of the rotation sensors 3, 4, and 5 is less than the threshold value. When a set time or more elapses while the normal combination state due to the establishment/non-establishment of the time determination formula is maintained, the number of times of abnormality detection of the rotation sensors 3, 4 and 5 (abnormality detection counter B) is reset.
Therefore, even if an abnormality of the rotation sensors 3, 4, 5 is detected by a combination of establishment/non-establishment of the three abnormality determination formulas, if the abnormality is detected due to a temporary cause, the rotation sensors 3, 4 , 5 is normal.

(6) Diagnosis of rotation sensors 3, 4, and 5 is performed in conjunction with gear ratio/neutral abnormality detection of automatic transmission AT.
The rotation sensor diagnosis controller (rotation sensor diagnosis unit 20a) prohibits the abnormality diagnosis of the rotation sensors 3, 4, and 5 when the gear ratio/neutral abnormality is detected before the abnormality diagnosis of the rotation sensors 3, 4, and 5. .
For this reason, if the gear ratio/neutral abnormality is detected prior to the abnormality diagnosis of the rotation sensors 3, 4, 5, the rotation sensors 3, 4 are detected by executing provisional limp home control or searching control based on the gear ratio/neutral abnormality detection. , 5 can be prevented from being erroneously diagnosed. That is, when the gear ratio/neutral abnormality is detected first, provisional limp home control or search control is performed based on the gear ratio/neutral abnormality detection. Therefore, if the abnormality diagnosis of the rotation sensors 3, 4, 5 is executed during the provisional limp home control or the probe control, the abnormality diagnosis of the rotation sensors 3, 4, 5 will be erroneously diagnosed due to control interference.

(7) The rotation sensor diagnosis controller (rotation sensor diagnostic unit 20a) diagnoses the rotation sensors 3, 4, and 5 for abnormality when the abnormality diagnosis for the rotation sensors 3, 4, and 5 is performed prior to the gear ratio/neutral abnormality detection. Execution of the gear ratio/neutral abnormality detection is continued without performing the abnormality processing based on the gear ratio/neutral abnormality detection, and the abnormality processing is performed based on the gear ratio/neutral abnormality detection.
Therefore, when abnormality diagnosis of the rotation sensors 3, 4, and 5 is performed prior to detection of gear ratio/neutral abnormality, priority can be given to execution of abnormality processing based on gear ratio/neutral abnormality detection. . That is, the abnormality diagnosis of the rotation sensors 3, 4, 5 is positioned as a part of the gear ratio/neutral abnormality detection, and safety is ensured by performing appropriate abnormality treatment in the rotation sensor abnormality detection area.

Although the rotation sensor diagnostic device for an automatic transmission according to the present invention has been described above based on the embodiments, the specific configuration is not limited to the embodiments, and can be set forth in each claim of the scope of claims. Design changes, additions, etc. are permitted as long as they do not deviate from the gist of the invention.

In the embodiment, the rotation sensor 3 is detected based on whether or not the abnormality detection counter B is counted by 1 or more at different gear stages (a plurality of gear stages) and the total value is equal to or greater than a threshold value (for example, 4 times). , 4 is abnormal (abnormal diagnosis). However, the determination of the abnormality may be made based on the number of gear stages in which it is impossible to distinguish between the rotation sensor abnormality and the gear ratio abnormality. For example, as in this embodiment, when there are three shift stages in which rotation sensor abnormality and gear ratio abnormality cannot be distinguished in the rotation sensor 3, the abnormality detection counter B is set to 1 at the four shift stages. If the number of rotations is counted as above, the diagnosis that the rotation sensor 3 is abnormal (abnormality diagnosis) may be confirmed. This is because there are three shift stages where it is impossible to distinguish between rotation sensor malfunction and gear ratio malfunction, but when there is an abnormality in four shift stages, it is possible to reliably determine that there is a rotation sensor malfunction. It is from.

In the embodiment, an example is shown in which the rotation sensor diagnostic device of the present invention is applied to an engine vehicle equipped with a stepped automatic transmission having seven forward speeds and one reverse speed. However, with regard to automatic transmissions, if the automatic transmission is equipped with a plurality of rotation sensors capable of acquiring an abnormality determination formula based on a specific relationship that enables rationality diagnosis, the number of gears, etc. is limited to the embodiment. do not have. In addition, as for applicable vehicles, the present invention can be applied to electric vehicles such as hybrid vehicles and electric vehicles in addition to engine vehicles.

Claims (9)

A rotation sensor diagnostic device for an automatic transmission comprising a rotation sensor diagnosis controller for diagnosing whether a rotation sensor for detecting the rotation speed of a rotation element of an automatic transmission having a plurality of shift stages is normal or abnormal,
The rotation sensor diagnostic controller comprises:
detecting an abnormality by comparing the number of rotations detected by a rotation sensor with the theoretical number of rotations for each shift stage of the automatic transmission;
Diagnosing an abnormality of the rotation sensor when an abnormality is detected in a different gear stage among the plurality of gear stages of the automatic transmission.
Rotation sensor diagnostic equipment for automatic transmissions. In the automatic transmission rotation sensor diagnostic device according to claim 1,
As rotation sensors of the automatic transmission, a first turbine rotation sensor for detecting a first turbine rotation speed, a second turbine rotation sensor for detecting a second turbine rotation speed, and an output rotation sensor for detecting an output rotation speed. and
The rotation sensor diagnostic controller comprises:
A first abnormality judgment expression using the first turbine rotation speed, the output rotation speed, and a gear ratio, and a second abnormality judgment expression using the second turbine rotation speed, the output rotation speed, and a gear ratio and a third abnormality judgment expression using the second turbine speed, wheel speed, and gear ratio,
Normality/abnormality of the rotation sensor is detected according to a combined state of establishment/non-establishment of the first abnormality judgment expression, the second abnormality judgment expression, and the third abnormality judgment expression.
Rotation sensor diagnostic equipment for automatic transmissions. In the automatic transmission rotation sensor diagnostic device according to claim 2,
When the rotation sensor diagnostic controller continues to maintain an abnormal combination state based on the establishment/non-establishment of the first abnormality determination formula, the second abnormality determination formula, and the third abnormality determination formula, a set time or more elapses. the rotation sensor detects an abnormality;
Rotation sensor diagnostic equipment for automatic transmissions. In the automatic transmission rotation sensor diagnostic device according to claim 3,
The rotation sensor diagnosis controller determines that the number of times the rotation sensor has detected an abnormality is equal to or greater than a threshold based on the minimum experience number of times that an abnormality has been detected at two or more different gear stages. Confirm the diagnosis that the sensor is abnormal,
Rotation sensor diagnostic equipment for automatic transmissions. In the automatic transmission rotation sensor diagnostic device according to claim 4,
The rotation sensor diagnosis controller determines whether the first abnormality determination formula, the second abnormality determination formula, and the third abnormality determination formula are established or not established when the number of times the rotation sensor has detected an abnormality is less than the threshold value. resetting the number of abnormal detections of the rotation sensor when a set time or more has elapsed while the normal combination state is maintained;
Rotation sensor diagnostic equipment for automatic transmissions. In the automatic transmission rotation sensor diagnostic device according to any one of claims 1 to 5,
The abnormality diagnosis of the rotation sensor is performed in combination with the gear ratio/neutral abnormality detection of the automatic transmission,
The rotation sensor diagnosis controller prohibits the abnormality diagnosis of the rotation sensor when the gear ratio/neutral abnormality is detected prior to the abnormality diagnosis of the rotation sensor.
Rotation sensor diagnostic equipment for automatic transmissions. In the automatic transmission rotation sensor diagnostic device according to claim 6,
The rotation sensor diagnosis controller does not perform abnormality processing based on the abnormality diagnosis of the rotation sensor when the abnormality diagnosis of the rotation sensor is performed prior to the gear ratio/neutral abnormality detection, and the gear ratio/neutral abnormality detection is performed. continue to execute, and perform anomaly processing based on the gear ratio/neutral anomaly detection;
Rotation sensor diagnostic equipment for automatic transmissions. In a method for diagnosing a rotation sensor for an automatic transmission for diagnosing whether a rotation sensor for detecting the rotation speed of a rotating element of an automatic transmission having a plurality of shift stages is normal or abnormal,
detecting an abnormality by comparing the number of rotations detected by a rotation sensor with the theoretical number of rotations for each shift stage of the automatic transmission;
Diagnosing an abnormality of the rotation sensor when an abnormality is detected in a different gear stage among the plurality of gear stages of the automatic transmission.
Rotation sensor diagnostic method for automatic transmission. In the automatic transmission rotation sensor diagnostic method according to claim 8,
As rotation sensors of the automatic transmission, a first turbine rotation sensor for detecting a first turbine rotation speed, a second turbine rotation sensor for detecting a second turbine rotation speed, and an output rotation sensor for detecting an output rotation speed. and
A first abnormality judgment expression using the first turbine rotation speed, the output rotation speed, and a gear ratio, and a second abnormality judgment expression using the second turbine rotation speed, the output rotation speed, and a gear ratio and a third abnormality judgment expression using the second turbine speed, wheel speed, and gear ratio,
Normality/abnormality of the rotation sensor is detected according to a combined state of establishment/non-establishment of the first abnormality judgment expression, the second abnormality judgment expression, and the third abnormality judgment expression.
Rotation sensor diagnostic method for automatic transmission.

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