JP2019152302A - Controller of automatic transmission - Google Patents

Abstract

To provide a controller of an automatic transmission capable of properly performing functional diagnosis of an input rotation sensor and an output rotation sensor.SOLUTION: A sensor diagnosis unit is configured to perform functional diagnosis of: a turbine rotation sensor for detecting a rotation speed of a transmission input shaft, in which driving force from an engine is input via a torque converter having a lock-up clutch; and an output shaft rotation sensor for detecting a rotation speed of a transmission output shaft that is connected to drive wheels and transmits the driving force to the drive wheels. The sensor diagnosis unit is also configured to, based on the engine rotation speed and the wheel rotation speed, when it is determined that engagement elements of the lock-up clutch and an automatic transmission are normal, perform the function diagnosis of the turbine rotation sensor and the output shaft rotation sensor.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a control device for an automatic transmission that diagnoses functions of an input rotation sensor that detects the rotation speed of an input member and an output rotation sensor that detects the rotation speed of an output member.

  2. Description of the Related Art Conventionally, there is known an automatic transmission control device that performs a function diagnosis of a speed change mechanism interposed between an input member and an output member (see, for example, Patent Document 1). In this automatic transmission control device, a drive source rotation sensor that detects the output rotation speed of the travel drive source, an input rotation sensor that detects the rotation speed of the input member, and an output rotation sensor that detects the rotation speed of the output member; The detected values of the three types of rotation sensors are compared, and the function of the output rotation sensor is diagnosed. Also, another diagnostic method is introduced to function-diagnose the output rotation sensor alone. Then, a function diagnosis method of the two types of output rotation sensors is combined to perform a function diagnosis of the transmission mechanism.

JP 2001-99304 A

  Incidentally, a torque converter having a lock-up clutch is disposed between the travel drive source and the input member. A fastening element for the automatic transmission is interposed between the input member and the output member. For this reason, unless the lock-up clutch and the fastening element are properly engaged, it is not possible to accurately compare and determine the detection values of the three types of rotation sensors. However, in the conventional automatic transmission control device, nothing is mentioned about the function diagnosis of the lock-up clutch and the fastening element. Therefore, there is a possibility that function diagnosis of the input rotation sensor and the output rotation sensor cannot be performed appropriately.

  The present invention has been made paying attention to the above problem, and an object thereof is to provide a control device for an automatic transmission that can appropriately perform function diagnosis of an input rotation sensor and an output rotation sensor.

In order to achieve the above object, the present invention includes an input member, an output member, an automatic transmission, an input rotation sensor, an output rotation sensor, and a transmission controller.
Here, the driving force from the travel drive source is input to the input member via a torque converter having a lock-up clutch.
The output member is connected to the driving wheel and transmits driving force to the driving wheel.
The automatic transmission is disposed between the input member and the output member, and has a plurality of gear trains and a plurality of clutches.
The input rotation sensor detects the number of rotations of the input member.
The output rotation sensor detects the number of rotations of the output member.
When there is a shift request, the transmission controller changes gears based on detection values of the input rotation sensor and the output rotation sensor, and executes a shift. In addition, a sensor diagnosis unit that performs function diagnosis of the input rotation sensor and the output rotation sensor is provided.
The sensor diagnosis unit performs functional diagnosis of the input rotation sensor and the output rotation sensor when it is determined that the lockup clutch and the clutch are normal based on the output rotation speed of the traveling drive source and the rotation speed of the drive wheel. Do.

  As described above, when the sensor diagnosis unit determines that the lockup clutch and the clutch are normal based on the output rotational speed of the traveling drive source and the rotational speed of the driving wheel, the function of the input rotational sensor and the output rotational sensor is determined. Since the diagnosis is performed, it is possible to appropriately perform the function diagnosis of the input rotation sensor and the output rotation sensor by eliminating the rotational speed deviation caused by the abnormality of the lockup clutch or the clutch of the automatic transmission.

1 is an overall system diagram illustrating an engine vehicle equipped with an automatic transmission to which a control device according to a first embodiment is applied. (A)-(c) is explanatory drawing which shows the relationship between a detected value and actual value when it determines with sensor abnormality. 1 is a skeleton diagram illustrating an example of an automatic transmission according to a first embodiment. 4 is a fastening table of fastening elements when achieving each gear stage in the automatic transmission according to the first embodiment. It is explanatory drawing which shows an example of the shift map in the automatic transmission of Example 1. FIG. 3 is a flowchart illustrating a flow of sensor diagnosis processing executed by the AT controller according to the first embodiment. It is a table | surface which shows the relationship between the rotation difference between rotation speeds, and the diagnostic result of a sensor function.

  Hereinafter, a mode for carrying out an automatic transmission control device of the present invention will be described based on a first embodiment shown in the drawings.

Example 1
The control device in the first embodiment is applied to an engine vehicle (an example of a vehicle) equipped with an automatic transmission that realizes a shift speed of 9 forward speeds and 1 reverse speed. Hereinafter, the configuration of the first embodiment will be described by being divided into “entire system configuration”, “detailed configuration of automatic transmission”, and “sensor diagnosis processing configuration”.

  As shown in FIG. 1, the engine vehicle of the first embodiment includes an engine 1 (traveling drive source), a torque converter 2, an automatic transmission 3, a final reduction mechanism 4, and left and right drive wheels 5. ing.

  The torque converter 2 has a lock-up clutch 7 that directly connects the engine output shaft 6a and the transmission input shaft 6b when the torque increasing function is not required.

  The automatic transmission 3 is arranged between a transmission input shaft 6b (input member) and a transmission output shaft 6c (output member), and a planetary gear constituting a gear train and a fastening element fastened or released by a speed change. Have A control valve unit 8 is attached to the automatic transmission 3. The control valve unit 8 includes a spool valve for shifting, an actuator such as a hydraulic circuit and a solenoid valve. Each actuator of the control valve unit 8 operates in response to a control command from the AT controller 10 (transmission controller).

  The final deceleration mechanism 4 is a mechanism that decelerates the rotation of the transmission output shaft 6c and transmits the rotation to the left and right drive wheels 5 by providing a differential function. The number of revolutions actually transmitted to the drive wheels 5 is adjusted by the final gear ratio if of the final reduction mechanism 4.

  As shown in FIG. 1, the engine vehicle includes an AT controller 10 (transmission controller), an engine controller 11, a VDC controller 12, and a CAN communication line C. Note that “AT” in the AT controller 10 is an abbreviation for “Automatic Transmission”. Further, “VDC” of the VDC controller 12 is an abbreviation for “Vehicle Dynamics Control”. “CAN” of the CAN communication line C is an abbreviation for “Controller Area Network”.

The AT controller 10 performs shift control by monitoring changes in the operating point (VSP, APO) determined by the vehicle speed (VSP) and the accelerator opening (APO) on the shift map (see FIG. 5). The shift control is controlled by the following basic pattern, for example.
1. Auto upshift by increasing the vehicle speed while maintaining the accelerator opening.
2. Foot release upshift by accelerator release operation.
3. Foot return upshift by accelerator return operation.
4). Power-on downshift due to a decrease in vehicle speed while maintaining the accelerator opening.
5. Small opening sudden step down shift when the amount of accelerator operation is small.
6). Large opening sudden depression downshift (kickdown) when the amount of accelerator operation is large.
7). Slow down downshift by slow accelerator operation and increased vehicle speed.
8). Coast downshift due to a decrease in vehicle speed when the accelerator is released.

  Here, the shift control by the AT controller 10 is performed based on detection values of the turbine rotation sensor 13 (input rotation sensor) and the output shaft rotation sensor 14 (output rotation sensor). That is, the AT controller 10 determines the start and end of the inertia phase during the shift, the completion of the shift, and the like based on the detection values of the turbine rotation sensor 13 and the output shaft rotation sensor 14, and issues a control command to the control valve unit 8. Output.

  The AT controller 10 includes, in addition to signals from the turbine rotation sensor 13 and the output shaft rotation sensor 14, an ATF oil temperature sensor 15, an accelerator opening sensor 16, an inhibitor switch 17, an intermediate shaft rotation sensor 18, an engine rotation sensor 19, and wheels. A signal from the speed sensor 20 or the like is input. The signal of the engine rotation sensor 19 is input via the engine controller 11 and the CAN communication line C. A signal from the wheel speed sensor 20 is input via the VDC controller 12 and the CAN communication line C.

  The turbine rotation sensor 13 detects the rotation speed of the turbine runner of the torque converter 2 (= the rotation speed of the transmission input shaft 6b) and sends a signal of the turbine rotation speed Nt to the AT controller 10. The output shaft rotation sensor 14 detects the rotation speed of the transmission output shaft 6 c of the automatic transmission 3 and sends a signal indicating the output shaft rotation speed No to the AT controller 10. The vehicle speed is obtained by calculation based on the output shaft rotational speed No. The ATF oil temperature sensor 15 detects the temperature of ATF (Automatic Transmission Fluid) and sends a signal of the ATF oil temperature TATF to the AT controller 10. The accelerator opening sensor 16 detects the accelerator opening by the driver's accelerator operation, and sends a signal of the accelerator opening APO to the AT controller 10. The inhibitor switch 17 detects the range position selected by the driver's selection operation to the select lever, the select button, etc., and sends a range position signal to the AT controller 10. The intermediate shaft rotation sensor 18 detects the rotation speed of the intermediate shaft (intermediate shaft = rotary member connected to the first carrier C1) and sends a signal of the intermediate shaft rotation speed Nint to the AT controller 10. The engine speed sensor 19 detects the output speed of the engine 1 and sends a signal of the engine speed Ne to the AT controller 10. The wheel speed sensor 20 detects the number of rotations of the drive wheel 5 and sends a signal of the wheel speed Ws to the AT controller 10.

  In the first embodiment, the AT controller 10 includes a sensor diagnosis unit 10 a that performs function diagnosis of the turbine rotation sensor 13 and the output shaft rotation sensor 14. Here, the function diagnosis is to determine whether or not the detection value of each sensor is shifted from the actual value (actual value). The state where the detected value is deviated from the actual value is when the deviation width between the detected value and the actual value is out of the predetermined range. For example, when the gap between the detected value and the actual value increases with time (see FIG. 2A), or when the detected value and the actual value have a certain gap (FIG. 2B). )), And the detected value is completely different from the actual value (see FIG. 2C). When the detected value is deviated from the actual value, the sensor is determined to be abnormal. When the detected value is not deviated from the actual value, the sensor is determined to be normal.

  The sensor diagnosis unit 10a then engages the lockup clutch 7 and the engagement based on the engine speed Ne (output speed of the travel drive source) and the speed of the drive wheels 5 (hereinafter referred to as “wheel speed Nw”). When it is determined that the fastening element inside is normal, functional diagnosis of the turbine rotation sensor 13 and the output shaft rotation sensor 14 is performed. The determination that the lock-up clutch 7 and the engagement element are normal is when the rotation difference between the engine speed Ne and the wheel rotation speed Nw is equal to or less than the first threshold value during the engagement of the lock-up clutch 7 and the engagement element. To be done. Here, the wheel rotation speed Nw is calculated by calculation based on the wheel speed Ws. Further, “during fastening of the lock-up clutch 7 and the fastening element” means that both the lock-up clutch 7 and the fastening element are completely fastened.

  Further, the sensor diagnosis unit 10a of the first embodiment performs function diagnosis of the turbine rotation sensor 13 and the output shaft rotation sensor 14 when it is determined that the wheel rotation speed Nw is normal. The determination that the wheel rotational speed Nw is normal is based on the detected value of the turbine rotation sensor 13 (hereinafter referred to as “turbine rotational speed Nt”) and the detected value of the output shaft rotational sensor 14 (hereinafter referred to as “rotating speed”). , “Output shaft rotational speed No”) is equal to or smaller than the fourth threshold value, and the rotational difference between the output shaft rotational speed No and the wheel rotational speed Nw is equal to or smaller than the third threshold value.

  Then, the sensor diagnosis unit 10a determines that the turbine rotation sensor 13 is abnormal when the rotation difference between the turbine rotation speed Nt and the engine rotation speed Ne exceeds the second threshold value while the lockup clutch 7 is engaged. . The sensor diagnosis unit 10a determines that the output shaft rotation sensor 14 is abnormal when the rotation difference between the output shaft rotation speed No and the wheel rotation speed Nw exceeds the third threshold value.

  The engine controller 11 performs engine torque limit control and the like by cooperative control with shift control in addition to various controls of the engine 1 alone. The AT controller 10 and the engine controller 11 are connected via a CAN communication line C capable of exchanging information in both directions. Therefore, when a torque information request is input from the AT controller 10, the engine controller 11 outputs information on the estimated engine torque Te and turbine torque Tt to the AT controller 10.

  The VDC controller 12 controls the vehicle pressure by controlling the brake pressures of the left and right drive wheels 5 and the left and right driven wheels. The AT controller 10 and the VDC controller 12 are connected via a CAN communication line C that can exchange information in both directions.

[Detailed configuration of automatic transmission]
As shown in FIG. 3, the automatic transmission 3 has a first planetary gear PG1 and a second planetary gear PG2 as planetary gears constituting a gear train in order from the transmission input shaft 6b to the transmission output shaft 6c. And a third planetary gear PG3 and a fourth planetary gear PG4.

  The first planetary gear PG1 is a single pinion type planetary gear, and includes a first sun gear S1, a first carrier C1 that supports a pinion that meshes with the first sun gear S1, and a first ring gear R1 that meshes with the pinion.

  The second planetary gear PG2 is a single pinion type planetary gear, and includes a second sun gear S2, a second carrier C2 that supports a pinion that meshes with the second sun gear S2, and a second ring gear R2 that meshes with the pinion.

  The third planetary gear PG3 is a single pinion type planetary gear, and includes a third sun gear S3, a third carrier C3 that supports a pinion that meshes with the third sun gear S3, and a third ring gear R3 that meshes with the pinion.

  The fourth planetary gear PG4 is a single pinion type planetary gear, and includes a fourth sun gear S4, a fourth carrier C4 that supports a pinion that meshes with the fourth sun gear S4, and a fourth ring gear R4 that meshes with the pinion.

  As shown in FIG. 3, the automatic transmission 3 includes a transmission input shaft 6b, a transmission output shaft 6c, a first connection member M1, a second connection member M2, and a transmission case TC. . In addition, the automatic transmission 3 includes a first brake B1, a second brake B2, a third brake B3, a first clutch K1, a second clutch K2, 3 clutches K3.

  The transmission input shaft 6b is a shaft to which driving force from the engine 1 is input via the torque converter 2, and is always connected to the first sun gear S1 and the fourth carrier C4. The transmission input shaft 6b is connected to the first carrier C1 via the second clutch K2 so as to be connected and disconnected.

  The transmission output shaft 6c is a shaft that outputs a driving force shifted to the drive wheels 5 via the propeller shaft and the final reduction mechanism 4, and is always connected to the third carrier C3. The transmission output shaft 6c is connected to the fourth ring gear R4 via the first clutch K1 so as to be connected and disconnected.

  The first connecting member M1 is a member that always connects the first ring gear R1 of the first planetary gear PG1 and the second carrier C2 of the second planetary gear PG2 without interposing a fastening element. The second connecting member M2 always connects the second ring gear R2 of the second planetary gear PG2, the third sun gear S3 of the third planetary gear PG3, and the fourth sun gear S4 of the fourth planetary gear PG4 without interposing a fastening element. Is a member.

  The first brake B1 is a frictional engagement element that can lock the rotation of the first carrier C1 with respect to the transmission case TC. The second brake B2 is a frictional engagement element that can lock the rotation of the third ring gear R3 with respect to the transmission case TC. The third brake B3 is a frictional engagement element that can lock the rotation of the second sun gear S2 with respect to the transmission case TC.

  The first clutch K1 is a frictional engagement element that selectively connects the fourth ring gear R4 and the transmission output shaft 6c. The second clutch K2 is a frictional engagement element that selectively couples between the transmission input shaft 6b and the first carrier C1. The third clutch K3 is a frictional engagement element that selectively couples the first carrier C1 and the second coupling member M2.

  FIG. 4 is a table of fastening elements when the automatic transmission 3 achieves the ninth forward speed in the D range and the reverse speed stage in the R range by combining three of the six fastening elements at the same time. . Hereinafter, based on FIG. 4, a description will be given of a shift configuration that establishes each shift stage. In FIG. 4, a fastening element fastened by “●” is shown, and a fastening element released by a blank is shown.

  The first speed (1st) is achieved by simultaneous engagement of the second brake B2, the third brake B3, and the third clutch K3. The second speed (2nd) is achieved by simultaneous engagement of the second brake B2, the second clutch K2, and the third clutch K3. The third speed (3rd) is achieved by simultaneous engagement of the second brake B2, the third brake B3, and the second clutch K2. The fourth speed (4th) is achieved by simultaneous engagement of the second brake B2, the third brake B3, and the first clutch K1. The fifth speed (5th) is achieved by simultaneous engagement of the third brake B3, the first clutch K1, and the second clutch K2. The first to fifth gears described above are underdrive gears with a reduction gear ratio having a gear ratio exceeding 1.

  The sixth speed (6th) is achieved by simultaneous engagement of the first clutch K1, the second clutch K2, and the third clutch K3. The sixth speed stage is a direct connection stage with a gear ratio = 1.

  The seventh speed (7th) is achieved by simultaneous engagement of the third brake B3, the first clutch K1, and the third clutch K3. The eighth speed (8th) is achieved by simultaneous engagement of the first brake B1, the first clutch K1, and the third clutch K3. The ninth speed (9th) is achieved by simultaneous engagement of the first brake B1, the third brake B3, and the first clutch K1. The 7th to 9th gears described above are overdrive gears with an increased gear ratio with a gear ratio of less than 1.

  Further, when performing an up shift to an adjacent shift stage among the shift stages from the first speed to the ninth speed, or when performing a down shift, the shift is performed as shown in FIG. That is, in the shift to the adjacent gear, the release of one fastening element and the fastening of the other fastening element are maintained while the fastening of the two fastening elements among the three fastening elements being fastened is maintained. Achieved by doing.

  The reverse speed (Rev) by selecting the R range position is achieved by simultaneously engaging the first brake B1, the second brake B2, and the third brake B3. When the N range position and the P range position are selected, all of the six fastening elements B1, B2, B3, K1, K2, and K3 are released.

  The AT controller 10 stores a shift map as shown in FIG. The shift by changing the gear position from the first gear to the ninth gear on the forward side by selecting the D range is performed according to this shift map. That is, when the operating point (VSP, APO) crosses the upshift line shown by the solid line in FIG. 5, an upshift request is issued. Further, when the operating point (VSP, APO) crosses the downshift line indicated by the broken line in FIG. 5, a downshift request is issued.

[Sensor function diagnosis configuration]
FIG. 6 is a flowchart illustrating the flow of the sensor function diagnosis process executed by the sensor diagnosis unit 10a of the AT controller 10 according to the first embodiment. Hereinafter, each step of FIG. 6 will be described.

In step S1, it is determined whether or not a fastening command is output to at least one of the fastening elements of the automatic transmission 3. If YES (there is a fastening command), the process proceeds to step S2. In the case of NO (no fastening command), the function diagnosis of the sensor such as the turbine rotation sensor 13 cannot be performed and the process proceeds to the end.
The case where the fastening command is not output is when the shift range selects the N range position or the P range position. At this time, the rotational relationship between the turbine rotational speed Nt and the output shaft rotational speed No changes depending on the fastening state of the fastening element, and accurate rotational difference determination cannot be performed.

In step S2, following the determination that there is a fastening command to the fastening element in step S1, the absolute value of the value obtained by subtracting the product of the output shaft rotational speed No and the target gear ratio from the turbine rotational speed Nt is calculated in advance. It is determined whether or not the set fourth threshold value or less. If YES (| Nt− (No × target gear ratio) | ≦ fourth threshold value), the process proceeds to step S3. If NO (| Nt− (No × target gear ratio) |> fourth threshold value), the function diagnosis of the sensor cannot be performed and the process proceeds to the end.
Here, “No × target gear ratio” is a value obtained by coaxially converting the output shaft rotational speed No with respect to the turbine rotational speed Nt. The “fourth threshold value” is set to a value of about 2 to 3% of the turbine speed Nt. That is, when | Nt− (No × target gear ratio) | ≦ fourth threshold value, the coaxial conversion values of the turbine rotational speed Nt and the output shaft rotational speed No are substantially the same values, and the turbine rotational sensor 13, the fastening element, It is estimated that all the output shaft rotation sensors 14 are normal. On the other hand, when | Nt− (No × target gear ratio) |> fourth threshold value, the coaxial conversion value between the turbine rotational speed Nt and the output shaft rotational speed No is deviated, and the turbine rotational sensor 13, the fastening element, It is estimated that at least one of the output shaft rotation sensors 14 is abnormal.

In step S3, following the determination of | Nt− (No × target gear ratio) | ≦ the fourth threshold value in step S2, the multiplication value of the wheel rotational speed Nw and the final gear ratio if is determined from the output shaft rotational speed No. It is determined whether or not the absolute value of the subtracted value is equal to or less than a preset third threshold value. If YES (| No- (Nw × if) | ≦ third threshold), the process proceeds to step S4. If NO (| No− (Nw × if) |> third threshold), the process proceeds to step S6.
Here, “Nw × if” is a value obtained by coaxially converting the wheel rotational speed Nw with respect to the output shaft rotational speed No. The “third threshold value” is set to a value of about 2 to 3% of the output shaft rotation speed No. That is, when | No− (Nw × if) | ≦ the third threshold value, the coaxial conversion values of the output shaft rotational speed No and the wheel rotational speed Nw are substantially the same value, and the output shaft rotational sensor 14 and the wheel speed sensor 20 Are estimated to be normal. On the other hand, when | No− (Nw × if) |> third threshold value, the output shaft rotational speed No and the wheel rotational speed Nw are separated from the coaxial conversion value, and the output shaft rotational sensor 14 or the wheel speed sensor 20 It is estimated that at least one is abnormal.

In step S4, following the determination that | No− (Nw × if) | ≦ the third threshold value in step S3, it is determined whether or not a predetermined time has elapsed. If YES (elapse of a predetermined time), the process proceeds to step S5. If NO (predetermined time has not elapsed), the process returns to step S1.
Here, the “predetermined time” is a time necessary for eliminating the determination error in step S3, and can be arbitrarily set, for example, 0.5 seconds.

In step S5, following the determination that the predetermined time has elapsed in step S4, it is determined that the wheel speed sensor 20 is normal, and the process proceeds to step S7.
The determination that “the wheel speed sensor 20 is normal” is “estimation that the turbine rotation sensor 13, the fastening element, and the output shaft rotation sensor 14 are all normal” in step S2, and “output” in step S3. This is based on “estimation that both the shaft rotation sensor 14 and the wheel speed sensor 20 are normal”.

In step S6, following the determination of | No− (Nw × if) |> third threshold value in step S3, it is determined that the wheel speed sensor 20 is abnormal and the function diagnosis of the sensor cannot be performed. Proceed to
The determination that “the wheel speed sensor 20 is abnormal” is made by “estimating that the turbine rotation sensor 13, the fastening element, and the output shaft rotation sensor 14 are all normal” in step S2, and “output” in step S3. This is based on “estimation that at least one of the shaft rotation sensor 14 and the wheel speed sensor 20 is abnormal”. That is, since it is estimated that the output shaft rotation sensor 14 is normal in step S2, when the output shaft rotation sensor 14 or the wheel speed sensor 20 is estimated to be abnormal in step S3, the wheel speed sensor 20 is abnormal. It can be judged that it has occurred.

In step S <b> 7, following the determination that the wheel speed sensor 20 is normal in step S <b> 5, it is determined whether or not an engagement command is output to the lockup clutch 7. If YES (there is a fastening command), the process proceeds to step S8. In the case of NO (no fastening command), the function diagnosis of the sensor cannot be performed and the process proceeds to the end.
In addition, the case where a fastening command is output is when the torque increase function by the torque converter 2 is not required. When the lockup clutch 7 is disengaged, the rotational relationship between the engine speed Ne and the wheel speed Nw changes depending on the degree of fluid slip of the torque converter 2, and an accurate rotational difference determination cannot be performed.

In step S8, following the determination that there is an engagement command for the lockup clutch 7 in step S7, whether or not an engagement command is output to at least one of the engagement elements of the automatic transmission 3 is determined. Judging. If YES (there is a fastening command), the process proceeds to step S9. In the case of NO (no fastening command), the function diagnosis of the sensor cannot be performed and the process proceeds to the end.
The case where the fastening command is not output is when the shift range selects the N range position or the P range position as in step S1. At this time, the rotational relationship between the engine rotational speed Ne and the wheel rotational speed Nw changes depending on the fastening state of the fastening element, and an accurate rotational difference determination cannot be performed.

In step S9, following the determination that there is a fastening command to the fastening element in step S8, the absolute value of the value obtained by subtracting the wheel rotational speed Nw from the value obtained by dividing the engine rotational speed Ne by the target gear ratio is set in advance. It is determined whether or not it is equal to or less than the first threshold value. If YES (| (Ne ÷ target gear ratio) −Nw | ≦ first threshold value), the process proceeds to step S10. If NO (| (Ne ÷ target gear ratio) −Nw |> first threshold value), the function diagnosis of the sensor cannot be performed and the process proceeds to the end.
Here, “Ne ÷ target gear ratio” is a value obtained by coaxially converting the engine speed Ne with respect to the wheel speed Nw. The “first threshold value” is set to a value of about 2 to 3% of the wheel rotation speed Nw. That is, when | (Ne ÷ target gear ratio) −Nw | ≦ first threshold, the coaxial conversion values of the engine speed Ne and the wheel speed Nw are substantially the same, and the engine speed sensor 19 and the lock-up clutch 7 The fastening element and the output shaft rotation sensor 14 are all assumed to be normal. On the other hand, when | (Ne ÷ target gear ratio) −Nw |> first threshold value, the engine rotational speed Ne and the wheel rotational speed Nw are separated from the coaxial conversion value, and the engine rotational sensor 19, the lockup clutch 7, It is estimated that at least one of the fastening element and the output shaft rotation sensor 14 is abnormal.

In step S10, following the determination of | (Ne / target gear ratio) −Nw | ≦ first threshold value in step S9, an absolute value of a value obtained by subtracting the engine speed Ne from the turbine speed Nt is set in advance. It is determined whether or not the second threshold value is exceeded. If YES (| Nt−Ne |> second threshold), the process proceeds to step S11. If NO (| Nt−Ne | ≦ second threshold), the process proceeds to step S13.
Here, the “second threshold value” is set to a value of about 2 to 3% of the turbine speed Nt. That is, when | Nt−Ne |> the second threshold value, the turbine rotational speed Nt and the engine rotational speed Ne are in a state of being separated, and at least one of the turbine rotational sensor 13, the lockup clutch 7, and the engine rotational sensor 19 is present. Presumed to be abnormal. On the other hand, when | Nt−Ne | ≦ the second threshold value, the turbine rotational speed Nt and the engine rotational speed Ne are substantially the same value, and the turbine rotational sensor 13, the lockup clutch 7, and the engine rotational sensor 19 are all normal. It is estimated to be.

In step S11, following the determination that | Nt−Ne |> second threshold value in step S10, it is determined whether or not a predetermined time has elapsed. If YES (elapsed time), the process proceeds to step S12. If NO (predetermined time has not elapsed), the process returns to step S7.
Here, the “predetermined time” is a time necessary for eliminating the determination error in step S10 and can be arbitrarily set.

In step S12, following the determination that the predetermined time has elapsed in step S11, it is determined that the turbine rotation sensor 13 is abnormal, and the process proceeds to the end.
The determination that “the turbine rotation sensor 13 is abnormal” is made in step S9 “estimation that the engine rotation sensor 19, the lockup clutch 7, the engagement element, and the output shaft rotation sensor 14 are all normal” This is based on “estimation that at least one of the turbine rotation sensor 13, the lockup clutch 7, and the engine rotation sensor 19 is abnormal” in S10. That is, in step S9, it is estimated that the engine rotation sensor 19 and the lockup clutch 7 are normal. For this reason, when at least one of the turbine rotation sensor 13, the lockup clutch 7, and the engine rotation sensor 19 is estimated to be abnormal in step S10, it can be determined that an abnormality has occurred in the turbine rotation sensor 13.

In step S13, following the determination of | Nt−Ne | ≦ second threshold value in step S10, the absolute value of the value obtained by subtracting the product of the wheel rotational speed Nw and the final gear ratio if from the output shaft rotational speed No. Whether or not exceeds a preset third threshold. If YES (| No− (Nw × if) |> third threshold), the process proceeds to step S14. If NO (| No− (Nw × if) | ≦ third threshold), the process proceeds to step S16.
Here, “Nw × if” is a value obtained by coaxially converting the wheel rotational speed Nw with respect to the output shaft rotational speed No. The “third threshold value” is set to a value of about 2 to 3% of the output shaft rotation speed No. That is, when | No− (Nw × if) |> the third threshold value, the coaxial conversion values of the output shaft rotational speed No and the wheel rotational speed Nw are deviated, and the output shaft rotational sensor 14 or the wheel speed sensor 20 It is estimated that at least one of is abnormal. On the other hand, when | No− (Nw × if) | ≦ the third threshold value, the output shaft rotation speed No and the wheel rotation speed Nw are substantially equal to each other in the coaxial conversion value, and the output shaft rotation sensor 14 and the wheel speed sensor 20 are Both are estimated to be normal.

In step S14, following the determination of | No− (Nw × if) |> third threshold value in step S13, it is determined whether or not a predetermined time has elapsed. If YES (elapse of a predetermined time), the process proceeds to step S15. If NO (predetermined time has not elapsed), the process returns to step S7.
Here, the “predetermined time” is a time necessary for eliminating the determination error in step S13, and can be arbitrarily set.

In step S15, following the determination that the predetermined time has elapsed in step S14, it is determined that the output shaft rotation sensor 14 is abnormal, and the process proceeds to the end.
The determination that “the output shaft rotation sensor 14 is abnormal” is “estimation that the engine rotation sensor 19, the lockup clutch 7, the engagement element, and the output shaft rotation sensor 14 are all normal” in step S9. This is based on “estimation that at least one of the output shaft rotation sensor 14 and the wheel speed sensor 20 is abnormal” in step S13. That is, since it is estimated that the wheel speed sensor 20 is normal in step S9, when at least one of the output shaft rotation sensor 14 or the wheel speed sensor 20 is estimated to be abnormal in step S13, the output shaft rotation sensor 14 is abnormal. Can be determined.

In step S16, following the determination of | No− (Nw × if) | ≦ third threshold in step S13, it is determined that both the turbine rotation sensor 13 and the output shaft rotation sensor 14 are normal, and the process proceeds to the end. .
Here, the determination that “the turbine rotation sensor 13 and the output shaft rotation sensor 14 are normal” is “the engine rotation sensor 19, the lockup clutch 7, the engagement element, and the output shaft rotation sensor 14 are all normal in step S9. "Estimation that the turbine rotation sensor 13, lockup clutch 7, and engine rotation sensor 19 are all normal" in step S10, and "Output shaft rotation sensor 14 and wheel speed sensor" in step S13. 20 is based on the assumption that all 20 are normal.

  Next, “problem of self-function diagnosis of turbine rotation sensor and output shaft rotation sensor” will be described, and subsequently “sensor function diagnosis processing operation” of the first embodiment will be described.

[Problems of self-function diagnosis of turbine rotation sensor and output shaft rotation sensor]
In the automatic transmission 3 according to the first embodiment, the turbine rotational speed Nt and the output shaft rotational speed No are monitored during the shift control, and the fastening and release of the fastening elements are controlled based on these rotational relationships. Therefore, it is necessary to guarantee the functions of the turbine rotation sensor 13 that detects the turbine rotation speed Nt and the output shaft rotation sensor 14 that detects the output shaft rotation speed No. And when an abnormality occurs in these sensors, it is assumed that proper control of the fastening elements cannot be secured, and measures such as limiting the execution of shifting are taken. Can be prevented.

  On the other hand, when performing a function diagnosis of the turbine rotation sensor 13 and the output shaft rotation sensor 14, a function diagnosis is performed based on a rotation difference obtained by comparing detection values of a plurality of sensors. FIG. 7 shows the relationship between the rotation difference between the various rotation speeds and the diagnosis result of the sensor function. In FIG. 7, “◯” indicates normality determination. “×” indicates a possibility of abnormality.

That is, the turbine rotational speed Nt and the engine rotational speed Ne are theoretically substantially the same value. Therefore, if these rotation differences are equal to or smaller than the second threshold value, it is determined that both the engine rotation sensor 19 that detects the engine rotation speed Ne and the turbine rotation sensor 13 that detects the turbine rotation speed Nt are normal. Further, at this time, it is considered that the lock-up clutch 7 of the torque converter 2 disposed between the engine 1 and the automatic transmission 3 is properly engaged. Therefore, it is determined that the lockup clutch 7 is also normal.
On the other hand, if the rotational difference between the turbine rotational speed Nt and the engine rotational speed Ne exceeds the second threshold value, the cause is any of the engine rotational sensor 19, the turbine rotational sensor 13, and the lockup clutch 7. Cannot be determined. Therefore, the possibility of abnormality is determined for all of the engine rotation sensor 19, the turbine rotation sensor 13, and the lockup clutch 7.

Further, the coaxial conversion values of the turbine rotation speed Nt and the output shaft rotation speed No are theoretically substantially the same value. Therefore, if these rotation differences are equal to or less than the fourth threshold, it is determined that both the turbine rotation sensor 13 and the output shaft rotation sensor 14 that detects the output shaft rotation speed No are normal. Further, at this time, it is considered that the fastening element of the automatic transmission 3 disposed between the transmission input shaft 6b and the transmission output shaft 6c is appropriately fastened. Therefore, the fastening element is also determined to be normal.
On the other hand, when the rotation difference of the coaxial conversion value between the turbine rotation speed Nt and the output shaft rotation speed No exceeds the fourth threshold value, the cause is the turbine rotation sensor 13, the output shaft rotation sensor 14, and the fastening element. It is not possible to determine which of these is. Therefore, the possibility of abnormality is determined for all of the turbine rotation sensor 13, the output shaft rotation sensor 14, and the fastening element.

Further, the coaxial conversion values of the output shaft rotational speed No and the wheel rotational speed Nw are theoretically substantially the same value. Therefore, if these rotation differences are equal to or smaller than the third threshold value, it is determined that both the output shaft rotation sensor 14 and the wheel speed sensor 20 that detects the wheel speed Ws for calculating the wheel rotation speed Nw are normal.
On the other hand, when the rotational difference of the coaxial conversion value between the output shaft rotational speed No and the wheel rotational speed Nw exceeds the third threshold value, the cause is either the output shaft rotational sensor 14 or the wheel speed sensor 20. Cannot be determined. Therefore, the possibility of abnormality is determined for both the output shaft rotation sensor 14 and the wheel speed sensor 20.

  On the other hand, when it is assumed that the wheel speed sensor 20 is normal, the function diagnosis of the output shaft rotation sensor 14 can be performed based on the rotation difference of the coaxial conversion value between the output shaft rotation speed No and the wheel rotation speed Nw. Become. Further, by using the result of the function diagnosis of the output shaft rotation sensor 14 based on the rotation difference of the coaxial conversion value between the output shaft rotation speed No and the wheel rotation speed Nw, the turbine rotation speed Nt and the output shaft rotation speed No. The function diagnosis of the turbine rotation sensor 13 can be performed based on the rotation difference of the coaxial conversion value. Further, the function diagnosis of the turbine rotation sensor 13 can be performed based on the rotation difference between the turbine rotation speed Nt and the engine rotation speed Ne by assuming that the engine rotation sensor 19 is normal.

  However, for example, even when it is assumed that the wheel speed sensor 20 is normal, the automatic transmission 3 is required for the coaxial conversion values of the turbine rotation speed Nt and the output shaft rotation speed No to be substantially the same. The fastening element it has to be fastened properly. That is, if the fastening element is not properly fastened, it may be determined that the sensor function is normal even if the sensor function is normal. Further, even if it is assumed that the engine rotation sensor 19 is normal, in order for the engine rotation speed Ne and the turbine rotation speed Nt to be substantially the same value, the torque disposed between the engine 1 and the automatic transmission 3 The lock-up clutch 7 of the converter 2 needs to be properly engaged. If the lock-up clutch 7 is not properly engaged, the rotational difference between the engine speed Ne and the turbine speed Nt varies depending on the engagement state of the lock-up clutch 7, and the sensor function is normal. May be determined to be abnormal.

  Therefore, when performing functional diagnosis of the turbine rotation sensor 13 and the output shaft rotation sensor 14, the lockup clutch 7 and the engagement element of the automatic transmission 3 must be normally engaged. That is, the function diagnosis of the turbine rotation sensor 13 and the output shaft rotation sensor 14 cannot be performed properly unless the function of the lock-up clutch 7 and the engagement element is guaranteed.

[Sensor function diagnosis processing action]
Hereinafter, the function diagnosis processing operation of the sensor performed by the sensor diagnosis unit 10a will be described based on the flowchart of FIG.

  In the control device of the first embodiment, when performing functional diagnosis of the turbine rotation sensor 13 and the output shaft rotation sensor 14, the processes of Step S1, Step S2, and Step S3 shown in the flowchart of FIG. 6 are sequentially performed. That is, the sensor diagnosis unit 10a determines whether there is a fastening command to the fastening element, the magnitude of the rotational difference between the turbine rotational speed Nt and the output shaft rotational speed No, and the magnitude of the rotational difference between the output shaft rotational speed No and the wheel rotational speed Nw. Judging in order.

  During the fastening of the fastening element, the rotational difference of the coaxial conversion value between the turbine rotational speed Nt and the output shaft rotational speed No is equal to or less than the fourth threshold value, and the coaxial conversion between the output shaft rotational speed No and the wheel rotational speed Nw. When the rotation difference between the values is equal to or smaller than the third threshold value, the processing from step S4 to step S5 is performed in order. That is, the sensor diagnosis unit 10a determines that the wheel speed sensor 20 is normal after a predetermined time has elapsed. When it is determined that the wheel speed sensor 30 is normal, the value of the wheel speed Ws detected by the wheel speed sensor 20 is considered to be accurate. Therefore, it can be determined that the wheel rotational speed Nw calculated by calculation based on the accurate wheel speed Ws is normal.

  On the other hand, when the fastening command to the fastening element is not output, or when the rotational difference of the coaxial conversion value between the turbine rotational speed Nt and the output shaft rotational speed No exceeds the fourth threshold value, the wheel speed Assuming that the function diagnosis of the sensor 20 cannot be performed, the sensor function diagnosis process is terminated.

  Further, during the fastening of the fastening element, even if the rotational difference of the coaxial conversion value between the turbine rotational speed Nt and the output shaft rotational speed No is equal to or smaller than the fourth threshold value, the coaxial between the output shaft rotational speed No and the wheel rotational speed Nw. When the rotation difference of the converted value exceeds the third threshold value, the process of step S6 is performed. That is, the sensor diagnosis unit 10a determines that the wheel speed sensor 20 is abnormal. And when abnormality has arisen in the wheel speed sensor 20, it is thought that the value of the wheel speed Ws detected by this wheel speed sensor 20 is not accurate. Therefore, it can be determined that the wheel rotational speed Nw calculated by calculation based on the inaccurate wheel speed Ws is abnormal. For this reason, it is determined that the function diagnosis of the turbine rotation sensor 13 and the output shaft rotation sensor 14 cannot be performed, and the sensor function diagnosis process is terminated.

  As described above, in the control device of the first embodiment, when the function diagnosis of the wheel speed sensor 20 cannot be performed or when it is determined that the wheel speed sensor 20 is abnormal, the sensor function diagnosis process is terminated. Thereby, the function diagnosis of the turbine rotation sensor 13 and the output shaft rotation sensor 14 can be performed after determining that the wheel speed sensor 20 is normal. Therefore, it is possible to guarantee the function of the wheel speed sensor 20 (= accuracy guarantee of the rotational speed of the drive wheel 5 (wheel rotational speed Nw)) and improve the accuracy of the function diagnosis of the turbine rotational sensor 13 and the output shaft rotational sensor 14. Can be planned.

  If it is determined that the wheel speed sensor 20 is normal (= the wheel rotation speed Nw is normal), the processing from step S7 to step S8 and step S9 shown in the flowchart of FIG. 6 is performed in order. That is, the sensor diagnosis unit 10a sequentially determines the presence / absence of an engagement command for the lockup clutch 7, the presence / absence of an engagement command for the engagement element, and the magnitude of the rotation difference between the engine rotation speed Ne and the wheel rotation speed Nw.

  When the rotation difference of the coaxial conversion value between the engine speed Ne and the wheel speed Nw is equal to or smaller than the first threshold value during the engagement of the lockup clutch 7 and the engagement element, the sensor diagnosis unit 10a performs the process in step S9. It judges "YES" and advances a process to step S10. On the other hand, when the engagement command is not output to either the lockup clutch 7 or the engagement element, or when the rotation difference of the coaxial conversion value between the engine rotation speed Ne and the wheel rotation speed Nw exceeds the first threshold value, Since the function diagnosis of the turbine rotation sensor 13 and the output shaft rotation sensor 14 cannot be performed, the function diagnosis process of the sensor is terminated.

  Here, the rotational difference of the coaxial conversion value between the engine rotational speed Ne and the wheel rotational speed Nw is theoretically substantially the same value. On the other hand, the drive force transmission path from the engine 1 to the drive wheels 5 includes a lockup clutch 7 and a fastening element of the automatic transmission 3 in the middle. From this, when the lock-up clutch 7 and the engagement element are engaged, the rotation difference between the coaxial conversion values of the engine rotation speed Ne and the wheel rotation speed Nw becomes substantially the same value (below the first threshold value). It can be determined that the engine rotation sensor 19, the wheel speed sensor 20, the lockup clutch 7, and all of the fastening elements are normal (see FIG. 7).

  That is, the sensor diagnosis unit 10a performs the processes from step S7 to step S8 and step S9 shown in the flowchart of FIG. 6 in order, so that the lock-up clutch 7 and the engagement element are based on the engine speed Ne and the wheel speed Nw. Functional diagnosis can be performed. When it is determined that the lockup clutch 7 and the engagement element are normal, that is, when “YES” is determined in Step S9, the sensor diagnosis unit 10a proceeds to Step S10 to rotate the turbine. Functional diagnosis of the sensor 13 and the output shaft rotation sensor 14 is performed.

  Thus, in the control device of the first embodiment, the function diagnosis of the turbine rotation sensor 13 and the output shaft rotation sensor 14 can be performed after the functions of the lock-up clutch 7 and the fastening element are guaranteed. As a result, due to a malfunction of the lock-up clutch 7 or the engagement element (for example, a state in which differential rotation has occurred despite instructing engagement in a state where there is no differential rotation on the input side and output side), Although the detected values of the turbine rotation sensor 13 and the output shaft rotation sensor 14 are not deviated from the actual values (actual values), it is possible to eliminate erroneous determination as being deviated. 13 and the output shaft rotation sensor 14 can be appropriately diagnosed.

  Further, in the first embodiment, it is determined that both the lockup clutch 7 and the engagement element are normal, and the coaxial conversion between the engine rotation speed Ne and the wheel rotation speed Nw is performed while the lockup clutch 7 and the engagement element are engaged. This is performed when the rotation difference of the value is equal to or less than the first threshold value. Therefore, the function diagnosis of the lock-up clutch 7 and the engagement element can be performed based on the two parameters (the engine speed Ne and the wheel speed Nw), and the number of parameters used during the function diagnosis can be minimized. Thereby, the error which arises at the time of the function diagnosis of the lockup clutch 7 and the engagement element can be suppressed, and the diagnosis can be performed with high accuracy.

  Then, in the control device of the first embodiment, when it is determined that the lockup clutch 7 and the engagement element are normal, the process of step S10 shown in the flowchart of FIG. 6 is performed. That is, the sensor diagnosis unit 10a determines the magnitude of the rotational difference between the turbine speed Nt and the engine speed Ne.

  When the rotational difference between the turbine rotational speed Nt and the engine rotational speed Ne exceeds the second threshold value, the processing from step S11 to step S12 is performed in order. That is, the sensor diagnosis unit 10a determines that the turbine rotation sensor 13 is abnormal after a predetermined time has elapsed.

  On the other hand, when the rotational difference between the turbine rotational speed Nt and the engine rotational speed Ne is equal to or smaller than the second threshold value, the process of step S13 is performed. That is, the sensor diagnosis unit 10a determines the magnitude of the rotation difference between the output shaft rotation speed No and the wheel rotation speed Nw.

  And when the coaxial conversion value of output-shaft rotational speed No and wheel rotational speed Nw exceeds the 3rd threshold value, the process of step S14 to step S15 is performed in order. That is, the sensor diagnosis unit 10a determines that the output shaft rotation sensor 14 is abnormal after a predetermined time has elapsed.

  On the other hand, when the coaxial conversion value between the output shaft rotational speed No and the wheel rotational speed Nw is equal to or smaller than the third threshold value, the process of step S16 is performed. That is, the sensor diagnosis unit 10a determines that both the turbine rotation sensor 13 and the output shaft rotation sensor 14 are normal.

  Thus, in the control device of the first embodiment, when the rotational difference between the turbine rotational speed Nt and the engine rotational speed Ne exceeds the second threshold value while the lockup clutch 7 is engaged, the turbine rotational sensor 13 is abnormal. Judge that there is. Therefore, the function diagnosis of the turbine rotation sensor 13 can be performed based on the two parameters (the turbine rotation speed Nt and the engine rotation speed Ne), and the number of parameters used during the function diagnosis can be minimized. Thereby, the error which arises at the time of the function diagnosis of the turbine rotation sensor 13 can be suppressed, and the diagnosis can be performed with high accuracy.

  Further, in the control device of the first embodiment, when the coaxial conversion value between the output shaft rotation speed No and the wheel rotation speed Nw exceeds the third threshold value, it is determined that the output shaft rotation sensor 14 is abnormal. Therefore, the function diagnosis of the output shaft rotation sensor 14 can be performed based on the two parameters (the output shaft rotation speed No and the wheel rotation speed Nw), and the number of parameters used during the function diagnosis can be minimized. Thereby, the error which arises at the time of the function diagnosis of the output shaft rotation sensor 14 can be suppressed, and the diagnosis can be performed with high accuracy.

  As described above, in the control device for the automatic transmission 3 according to the first embodiment, the following effects can be obtained.

(1) An input member (transmission input shaft 6b) to which driving force from a travel drive source (engine 1) is input via a torque converter 2 having a lock-up clutch 7.
An output member (transmission output shaft 6c) connected to the drive wheels 5 and transmitting the drive force to the drive wheels 5,
An automatic transmission 3 disposed between an input member (transmission input shaft 6b) and an output member (transmission output shaft 6c), and having a plurality of gear trains (planetary gears) and a plurality of fastening elements;
An input rotation sensor (turbine rotation sensor 13) for detecting the rotation speed of the input member (transmission input shaft 6b);
An output rotation sensor (output shaft rotation sensor 14) for detecting the rotation speed of the output member (transmission output shaft 6c);
When there is a shift request, a transmission controller (AT controller 10) that executes a shift by changing the fastening element based on the detection values of the input rotation sensor (turbine rotation sensor 13) and the output rotation sensor (output shaft rotation sensor 14) With
The transmission controller (AT controller 10) includes a sensor diagnosis unit 10a that performs function diagnosis of an input rotation sensor (turbine rotation sensor 13) and an output rotation sensor (output shaft rotation sensor 14).
Based on the output rotational speed (engine rotational speed Ne) of the traveling drive source (engine 1) and the rotational speed of the driving wheel 5 (wheel rotational speed Nw), the sensor diagnosis unit 10a has the lockup clutch 7 and the engagement element normal. When it is determined that there is a function, the function diagnosis of the input rotation sensor (turbine rotation sensor 13) and the output rotation sensor (output shaft rotation sensor 14) is performed.
Thereby, the function diagnosis of the input rotation sensor (turbine rotation sensor 13) and the output rotation sensor (output shaft rotation sensor 14) can be performed appropriately.

(2) While the lockup clutch 7 and the engagement element are engaged, the sensor diagnosis unit 10a outputs the output rotational speed (engine rotational speed Ne) of the traveling drive source (engine 1) and the rotational speed of the drive wheels 5 (wheel rotational speed Nw). When the rotation difference of the coaxial conversion value is equal to or less than the first threshold value, the lockup clutch 7 and the engagement element are determined to be normal.
Thereby, the number of parameters used at the time of function diagnosis of the lock-up clutch 7 and the engaging element can be minimized and the diagnosis can be performed with high accuracy.

(3) While the lockup clutch 7 is engaged, the sensor diagnostic unit 10a detects the detected value (turbine rotation speed Nt) of the input rotation sensor (turbine rotation sensor 13) and the output rotation speed (engine) of the travel drive source (engine 1). When the rotation difference from the rotation speed Ne) exceeds the second threshold, the input rotation sensor (turbine rotation sensor 13) is determined to be abnormal.
Thereby, the number of parameters used at the time of function diagnosis of the input rotation sensor (turbine rotation sensor 13) can be minimized and diagnosed with high accuracy.

(4) The sensor diagnosing unit 10a determines the rotation difference between the coaxial conversion values between the detected value (output shaft rotation speed No) of the output rotation sensor (output shaft rotation sensor 14) and the rotation speed of the drive wheels 5 (wheel rotation speed Nw). When the value exceeds the third threshold, the output rotation sensor (output shaft rotation sensor 14) is determined to be abnormal.
Thereby, the number of parameters used at the time of function diagnosis of the output rotation sensor (output shaft rotation sensor 14) can be minimized and diagnosed with high accuracy.

(5) The sensor diagnosis unit 10a detects the detected value (turbine rotation speed Nt) of the input rotation sensor (turbine rotation sensor 13) and the detected value (output shaft) of the output rotation sensor (output shaft rotation sensor 14) during fastening of the fastening element. The rotation difference of the coaxial conversion value with the rotation speed No) is equal to or less than the fourth threshold value, and the detected value (output shaft rotation speed No) of the output rotation sensor (output shaft rotation sensor 14) and the rotation speed of the drive wheel 5 (wheels) When the rotational difference of the coaxial conversion value with respect to the rotational speed Nw) is equal to or smaller than the third threshold value, it is determined that the rotational speed of the drive wheel 5 (wheel rotational speed Nw) is normal,
When it is determined that the rotation speed (wheel rotation speed Nw) of the drive wheel 5 is normal, the function diagnosis of the input rotation sensor (turbine rotation sensor 13) and the output rotation sensor is performed.
As a result, the function of the wheel speed sensor 20 can be guaranteed (= the accuracy of the rotational speed of the drive wheel 5 (wheel rotational speed Nw)), and the function diagnosis of the turbine rotation sensor 13 and the output shaft rotation sensor 14 can be improved. Can be achieved.

  The control device for the automatic transmission according to the present invention has been described based on the first embodiment. However, the specific configuration is not limited to the first embodiment, and design changes and additions are permitted without departing from the gist of the invention according to each claim of the claims.

  In the first embodiment, the function diagnosis of the wheel speed sensor 20 is performed, and the function diagnosis of the turbine rotation sensor 13 and the output shaft rotation sensor 14 is performed after it is determined that the wheel speed sensor 20 is normal. However, the function diagnosis of the wheel speed sensor 20 may not be performed. That is, assuming that the wheel speed sensor 20 is normal, it may be determined whether or not the lockup clutch 7 and the engagement element are normal.

  In the first embodiment, an example in which a signal from the wheel speed sensor 20 is input via the VDC controller 12 and the CAN communication line C is shown, but the present invention is not limited thereto. The signal from the wheel speed sensor 20 may be input to the AT controller 10 through, for example, an ABS (Antilock Break System) controller, a TCS (Traction Control System) controller, or the like, or input directly to the AT controller 10. May be.

  In the first embodiment, an example of the automatic transmission 3 with 9 forward speeds and 1 reverse speed is shown as the automatic transmission. However, as an automatic transmission, it may be an example of an automatic transmission having a stepped gear stage other than 9 forward speeds and 1 reverse speed, and as an example of a continuously variable transmission having a forward clutch and a reverse brake as fastening elements. Also good.

  In the first embodiment, an example of a control device for an automatic transmission mounted on an engine vehicle has been described. It is.

1 Engine (traveling drive source)
2 Torque converter 3 Automatic transmission 4 Final deceleration mechanism 5 Drive wheel 6a Engine output shaft 6b Transmission input shaft (input member)
6c Transmission output shaft (output member)
7 Lock-up clutch 10 AT controller (transmission controller)
10a Sensor diagnosis unit 13 Turbine rotation sensor (input rotation sensor)
14 Output shaft rotation sensor (Output rotation sensor)
19 Engine rotation sensor 20 Wheel speed rotation sensor

Claims (5)

An input member to which a driving force from a travel drive source is input via a torque converter having a lock-up clutch;
An output member connected to the drive wheel for transmitting the drive force to the drive wheel;
An automatic transmission disposed between the input member and the output member and having a plurality of gear trains and a plurality of fastening elements;
An input rotation sensor for detecting the rotation speed of the input member;
An output rotation sensor for detecting the rotation speed of the output member;
When there is a shift request, a transmission controller that executes a shift by switching the fastening element based on detection values of the input rotation sensor and the output rotation sensor,
The transmission controller has a sensor diagnosis unit that performs function diagnosis of the input rotation sensor and the output rotation sensor,
When the sensor diagnosis unit determines that the lock-up clutch and the fastening element are normal based on the output rotation speed of the travel drive source and the rotation speed of the drive wheel, the input rotation sensor and the output A control device for an automatic transmission characterized by performing a function diagnosis of a rotation sensor. The control device for an automatic transmission according to claim 1,
When the rotation difference between the output rotational speed of the travel drive source and the rotational speed of the drive wheel is equal to or less than a first threshold during the engagement of the lockup clutch and the fastening element, the sensor diagnosis unit A control device for an automatic transmission, wherein the fastening element is determined to be normal. In the control device for an automatic transmission according to claim 1 or 2,
When the rotation difference between the detected value of the input rotation sensor and the output rotation speed of the travel drive source exceeds a second threshold value while the lockup clutch is engaged, the sensor diagnosis unit detects that the input rotation sensor is abnormal. A control device for an automatic transmission, characterized in that The control apparatus for an automatic transmission according to any one of claims 1 to 3,
The sensor diagnosis unit determines that the output rotation sensor is abnormal when a rotation difference between a detection value of the output rotation sensor and a rotation speed of the driving wheel exceeds a third threshold value. Transmission control device. In the automatic transmission control device according to any one of claims 1 to 4,
The sensor diagnosis unit is configured such that a rotation difference between a detection value of the input rotation sensor and a detection value of the output rotation sensor is equal to or less than a fourth threshold value during fastening of the fastening element, and the detection value of the output rotation sensor and the detection value When the rotational difference from the rotational speed of the driving wheel is equal to or less than the third threshold, it is determined that the rotational speed of the driving wheel is normal,
When it is determined that the rotational speed of the drive wheel is normal, functional diagnosis of the input rotation sensor and the output rotation sensor is performed.