JP2019082187A - Control device of automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic transmission capable of appropriately determining a pseudo D state. In the control device for an automatic transmission of the present invention, when a driver operates a shift lever to select a traveling range, an input side rotation speed of a clutch detected by a first sensor and a second sensor When the difference in rotation speed from the rotation speed on the output side detected by the above is greater than or equal to the difference in the first rotation speed, the pseudo D state determination means for determining the pseudo D state in which the manual valve switching is insufficient, and the first sensor When the difference in rotation speed from the second sensor is greater than or equal to the difference in second rotation speed larger than the difference in first rotation speed, the sensor abnormality detecting means for determining the sensor abnormality and the pseudo D state determining means include the pseudo D state. After that, when the sensor abnormality detecting means determines that the sensor is abnormal, it is decided to clear the determination result of the pseudo D state. [Selection diagram] Fig. 4

Description

  The present invention relates to an automatic transmission that switches a travel range position by shift lever operation.

  According to Patent Document 1, when it is detected that the clutch disposed between the engine and the drive wheel is equal to or greater than a predetermined rotational speed difference in a state recognized as the D range position by shift lever operation, a so-called pseudo D state There is disclosed a technology for determining In the pseudo D state, even if the range position signal is at the D range position, switching of the manual valve operated in conjunction with the shift lever is not sufficiently performed, and it is determined that the hydraulic pressure supply is insufficient. . When it is determined to be the pseudo D state, for example, pseudo D control is performed which suppresses the clutch engagement pressure and avoids the shock accompanying sudden engagement of the clutch when the hydraulic pressure supply is restored.

International Publication WO 2014/034280

  However, in the technique of Patent Document 1, the difference in the number of revolutions for determining the abnormality of the revolution sensor at the time of detecting the slip of the clutch is larger than the predetermined number of revolutions difference in determining the pseudo D state. Therefore, it is determined that the pseudo D state is present before the sensor abnormality detection, and it is difficult to discriminate between the pseudo D state and the sensor abnormal state.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an automatic transmission capable of appropriately determining a pseudo D state.

In the control device for an automatic transmission according to the present invention, a clutch disposed between a drive source and a drive wheel;
An automatic transmission disposed between the clutch and the drive wheel;
Hydraulic control means for supplying an engagement pressure to the clutch via a manual valve operated in conjunction with the operation of the shift lever;
A first sensor that detects an input side rotational speed of the clutch;
A second sensor that detects an output side rotational speed of the clutch;
When the driver operates the shift lever to select the travel range, the rotation of the input-side rotational speed of the clutch detected by the first sensor and the output-side rotational speed detected by the second sensor Pseudo D state determination means for determining a pseudo D state in which switching of the manual valve is insufficient when the number difference is equal to or greater than the first rotation speed difference;
Sensor abnormality detection means for judging as sensor abnormality when the rotational speed difference between the first sensor and the second sensor is equal to or larger than a second rotational speed difference larger than the first rotational speed difference;
Equipped with
The pseudo D state determination means clears the determination result of the pseudo D state when it is determined that the sensor abnormality is detected by the sensor abnormality detection means after the determination as the pseudo D state.

  Therefore, even after the determination as the pseudo D state, it is possible to detect the case where the pseudo D state is determined due to the sensor abnormality, and the determination result of the pseudo D state can be appropriately cleared.

FIG. 1 is a schematic view illustrating a configuration of an automatic transmission according to a first embodiment. It is a schematic diagram showing a pseudo D state. 7 is a time chart illustrating a pseudo D control process of the first embodiment. FIG. 10 is a flowchart illustrating a pseudo D state determination result clear process according to the first embodiment. 5 is a map used in the abnormal area determination process of the first embodiment. 5 is a map used in the abnormal area determination process of the first embodiment. 5 is a map used in the abnormal area determination process of the first embodiment. 5 is a map used in the abnormal area determination process of the first embodiment.

Example 1
FIG. 1 is a schematic view illustrating the configuration of an automatic transmission according to a first embodiment. The automatic transmission shifts the rotation output from the engine 1 and transmits it to the drive wheels 6. The automatic transmission has a torque converter 2, a forward / reverse switching mechanism 3, a belt type continuously variable transmission 4, and a differential gear 5. The torque converter 2 has a lockup clutch 2a that directly connects the engine output shaft 10 connected to the engine 1 and the turbine shaft 11. The forward / reverse switching mechanism 3 has a planetary gear set, two friction coupling elements (hydraulic actuators) (a forward clutch that achieves a forward state by fastening, and a reverse brake that achieves a reverse state by fastening). Hereinafter, these two frictional engagement elements are collectively referred to as a clutch 3a.

  The input side of the clutch 3 a is connected to the turbine shaft 11, and the output side of the clutch 3 a is connected to the input shaft 12 of the belt type continuously variable transmission 4. The belt type continuously variable transmission 4 has a primary pulley 4a, a belt 4b and a secondary pulley 4c. The secondary pulley 4 c is connected to the output shaft 13. Between the differential gear 5 and the drive wheel 6, a drive shaft 35 that rotates integrally with the drive wheel 6 is provided.

  The control valve 20 has an oil pump OP driven by the engine 1 as a hydraulic pressure source, and has a plurality of control valves that regulate various control hydraulic pressures and supply the hydraulic actuators with the hydraulic pressure. The control valve 20 has a manual valve 21 that switches the supply destination of the hydraulic pressure to the hydraulic actuator including the clutch 3a. The manual valve 21 is a valve connected to the shift lever 40 via a mechanical link mechanism, and interlocks with the operation of the shift lever 40. When the shift lever 40 is in the N range position, it is in the valve position for draining the clutch engagement pressure Pcl, and in the D range position, it is in the valve position where the clutch engagement pressure Pcl can be supplied to the clutch 3a.

  In the automatic transmission, an engine rotational speed sensor 31 for detecting the rotational speed of the engine output shaft 10 (hereinafter referred to as an engine rotational speed Ne) and the rotational speed of the turbine shaft 11 (hereinafter referred to as a turbine rotational speed Nt) ), A primary rotational speed sensor 33 for detecting the rotational speed of the input shaft (primary pulley 4a) 12 (hereinafter referred to as primary rotational speed Npri), and an output shaft 13 (secondary). A secondary rotation number sensor 34 for detecting the rotation number (hereinafter referred to as secondary rotation number Nsec) of the pulley 4c) and a wheel speed for detecting the rotation number of the drive wheel 6 (hereinafter referred to as wheel speed VW) An inhibitor that detects the range position signal selected by the sensor 35 and the shift lever 40 operated by the driver Having a switch 36, an APO sensor 37 for detecting an accelerator pedal opening APO, the. An automatic transmission control unit (ATCU) 100 receives signals from various sensor groups, performs hydraulic control according to the traveling state, and supplies hydraulic pressure to the hydraulic actuator.

  FIG. 2 is a schematic view showing a pseudo D state. FIG. 2 (A) shows the positional relationship between the shift lever 40 and the inhibitor switch 36, and FIG. 2 (B) shows the positional relationship between the shift lever 40 and the manual valve 21. The inhibitor switch 36 has a region corresponding to each range position of the P range position, the N range position, and the D range position, and outputs the D range position signal from the region where the shift lever 40 outputs the N range position signal. When it shifts to, D range position signal is output. The position of the shift lever 40 indicated by the dotted line in FIG. 2A is the proper D-range position to be positioned by the detent plate or the like. On the other hand, the manual valve 21 is installed movably in the axial direction in the valve housing hole 20b. A clutch engagement pressure introduction oil passage 20a to which the clutch engagement pressure Pcl is supplied opens in the valve accommodation hole 20b, and a clutch engagement pressure supply oil passage 20c connected to the hydraulic pressure chamber of the clutch 3a opens. When the shift lever 40 is in the N range position, the manual valve 21 disconnects the clutch engagement pressure introduction oil passage 20a from the clutch engagement pressure supply oil passage 20c. When the shift lever 40 moves toward the D range position, the manual valve 21 brings the clutch engagement pressure introduction oil passage 20a into communication with the clutch engagement pressure supply oil passage 20c. The position of the manual valve 21 indicated by the dotted line in FIG. 2B is the manual valve position according to the appropriate D range position.

  When the driver operates from the N range position to the D range position as in the position of the shift lever 40 shown by the solid line in FIG. 2A, the movement of the shift lever 40 is stopped before reaching the appropriate D range position. There is a case. At this time, although the range position signal of the inhibitor switch 36 outputs the D range position signal, as in the position of the manual valve 21 shown by the solid line in FIG. The pressure supply oil passage 20c is not moved to the position where the communication with the pressure supply oil passage 20c is completely established. Thus, the clutch engagement pressure Pcl may not be sufficiently supplied. Then, in the ATCU 100, although control according to the D range position is started, the hydraulic pressure actually supplied to the clutch 3a becomes low, and slip due to the lack of the engagement capacity of the clutch 3a occurs. As described above, in a state where the inhibitor switch 36 outputs the D range position signal, a state in which the position of the manual valve 21 is not moved to an appropriate position is referred to as a pseudo D state.

  As described above, in the situation where it is determined to be in the pseudo D state, the engine rotation speed Ne tends to blow up because the clutch engagement pressure Pcl is insufficient. Further, temporarily, ATCU 100 recognizes an appropriate D range position without recognizing it as a pseudo D state, performs precharging as an engagement command of clutch 3a, gradually raises clutch engagement pressure Pcl, and then completely completes It is assumed that the command leading to the fastening is output. In this state, when the manual valve 21 moves to the appropriate position, the high clutch engagement pressure Pcl is supplied at once to the clutch 3a from the clutch engagement pressure supply oil passage 20c. Then, the engine rotational speed Ne, which tends to blow up, is pushed down at a stretch, and the inertia torque at that time is output to the drive wheel 6 side, which may cause a fastening shock. Therefore, after the determination as the pseudo D state, pseudo D control processing for avoiding a fastening shock is executed.

FIG. 3 is a time chart showing the pseudo D control process of the first embodiment. This time chart shows a state where the position of the shift lever 40 is at the P range position and the vehicle is started from the vehicle stop state.
At time t1, the driver moves the shift lever 40 to the D range position, and the vehicle starts moving. Then, at time t2, the lockup clutch 2a is engaged (ON) in order to improve fuel consumption.
At time t3, when the rotation speed difference ΔNce between the turbine rotation speed Nt which is the slip amount of the clutch 3a and the primary rotation speed Np becomes larger than the predetermined rotation speed ΔN1 for determining the pseudo D state, the pseudo D state is determined. , Release the lockup clutch 2a (OFF). Thereby, the inertia torque fluctuation on the engine side is suppressed when the clutch 3a is reengaged. Further, the secondary hydraulic pressure Psec supplied to the secondary pulley 4c is set to be high, and the belt 4b is prevented from slipping due to the shock accompanying the re-engagement. Further, the clutch engagement pressure Pcl is set to a capacity that is low enough for engagement.
When slip amount .DELTA.Nce of clutch 3a falls below predetermined rotation speed .DELTA.N1 at time t4, it is determined that the pseudo D state has been eliminated, and the secondary hydraulic pressure Psec is returned from the high setting to the normal setting and the clutch engagement pressure Pcl is lowered. Return from the setting of to the normal setting. Then, the lockup clutch 2a is engaged. Thereby, the fastening shock at the time of manual valve 21 moving to a proper position from a false D state is avoided.

  As described above, when the pseudo D control process is performed, it is determined whether the slip amount ΔNce is larger than ΔN1. On the other hand, various sensor groups such as the engine speed sensor 31 and the turbine speed sensor 32 mutually calculate the difference between the detection values of the respective speed sensors, and execute the sensor abnormality determination process. For example, the differences (Ne-Npri), (Ne-Nt), and (Nt-Npri) between the engine speed sensor 31, the turbine speed sensor 32, and the primary speed sensor 33 are monitored, and the difference is predetermined. If it is larger than the rotational speed ΔN2, a sensor that is outputting an abnormal rotational speed signal is specified from the combination of the increased difference, and it is determined that the sensor is abnormal.

  At this time, in order to determine the abnormality of the above three sensors, if the lockup clutch 2a is not engaged, it is not possible to satisfy the condition that the respective rotational speeds coincide at normal time, and the sensor abnormality determination processing It can not be implemented. Also, in general, since .DELTA.N2 is set to a rotational speed larger than .DELTA.N1, when (Nt-Npri) reaches .DELTA.N1, it is judged as a pseudo D state and the lockup clutch 2a is released, so that the sensor abnormality There is a problem that it can not proceed to the determination process. Therefore, in the first embodiment, after the determination as the pseudo D state, while performing the pseudo D control process, the possibility of the sensor abnormality being detected is detected based on the states of the various sensors, and the sensor abnormality can occur When there is a sex, the determination result of the pseudo D state is cleared, and it is possible to shift to the sensor abnormality determination process.

FIG. 4 is a flowchart showing the pseudo D state determination result clear process of the first embodiment.
In step S1, it is determined whether or not the rotational speed difference .DELTA.Nce between the turbine rotational speed Nt, which is the slip amount of the clutch 3a, and the primary rotational speed Npri is larger than a predetermined rotational speed .DELTA.N1 for determining a pseudo D state. When it is determined that the state is a pseudo D state, the process proceeds to step S2, and in other cases, the process proceeds to the sensor abnormality determination process of step S6.
In step S2, the above-described pseudo D control process is performed.
In step S3, an abnormal area determination process is performed. In the abnormal area determination process, values of various rotation speed sensors in execution of the pseudo D control process are read in a map in which an abnormal area of the sensor is set in advance. The details of the abnormal area determination process will be described later.
In step S4, it is determined whether or not the values of various sensors are within the abnormal area, and when it is determined that the values are within the abnormal area, the process proceeds to step S5, and in other cases, the process returns to step S1 and the pseudo D control process is continued. Do.
In step S5, the determination result that it is a pseudo D state is cleared.
In step S6, sensor abnormality determination processing is performed.

Next, the abnormal area determination process will be described. 5 to 8 are maps used in the abnormal area determination process of the first embodiment.
FIG. 5 is a map determined based on the relationship between the engine speed sensor 31 and the turbine speed sensor 32 in the drive state in which the accelerator pedal is depressed. Since the lockup clutch 2a is released while the pseudo D control process is being performed, the engine rotation speed Ne and the turbine rotation speed Nt in the drive state are in a state where an offset for the relative rotation speed in the torque converter 2 is generated. . Therefore, through the operating point determined by the relationship between the engine speed Ne and the turbine speed Nt at the time of starting the pseudo D control processing, a reference line is established in which the engine speed Ne and the turbine speed Nt are proportional to each other. Do. Next, the low rotation threshold Smin is set on the low rotation speed side of the reference line, the high rotation threshold Smax is set on the high rotation speed side of the reference line, and a region surrounded by Smax and Smin is a normal region, otherwise Is defined as an abnormal area.

  For example, when the engine speed sensor 31 and the turbine speed sensor 32 are both normal as shown in the lower part of the map in FIG. 5, the turbine speed Nt also increases with the increase of the engine speed Ne. In order to do this, the operating point should move diagonally upward within the normal range. On the other hand, when an abnormality occurs in which the sensor output value gradually decreases in the turbine rotational speed sensor 32, the operating point moves in a direction different from the direction considered to move at normal time, and falls below Smin and is within the abnormal area. Move to In this case, it is determined that the rotational speed difference ΔNce at the time of determination in step S1 may have been generated due to a sensor abnormality, and the pseudo D control process is interrupted to shift to a sensor abnormality determination process. Thus, moving in a direction different from the direction in which the operating point moves in the drive state means that the sign of the time change gradient of the engine rotational speed Ne detected by the engine rotational speed sensor 31 after determination as the pseudo D state This means that the sign of the turbine rotational speed Nt detected by the turbine rotational speed sensor 32 is different from that of the time change gradient of the turbine rotational speed Nt. Since the determination result of the pseudo D state is cleared based on the sign of such a time change gradient, the determination accuracy is enhanced. Further, in the drive state, the determination accuracy can be improved by determining whether or not the operating area is an abnormal area based on whether or not the operating point falls below Smin.

FIG. 6 is a map determined based on the relationship between the engine speed sensor 31 and the turbine speed sensor 32 in the coast state where the accelerator pedal is released. Since the lockup clutch 2a is released while the pseudo D control process is being performed, the engine rotation speed Ne and the turbine rotation speed Nt in the coast state are in a state where an offset for the relative rotation speed in the torque converter 2 is generated. . The reference line, the low rotation threshold value Smin and the high rotation threshold value Smax are set in the same manner as in the case described in FIG.
For example, as shown in the lower part of the map of FIG. 6, when both the engine speed sensor 31 and the turbine speed sensor 32 are normal, the engine speed Ne also decreases with the decrease of the turbine speed Nt. Should move toward the origin within the normal range. On the other hand, when an abnormality occurs in which the sensor output value gradually rises in the turbine rotational speed sensor 32, the operating point moves in a direction different from the direction considered to move at the normal time, exceeding Smax and within the abnormal area. Move to the state of “d” means the sign of the temporal change gradient of the engine rotational speed Ne detected by the engine rotational speed sensor 31 after determining that it is a pseudo D state, and the time of the turbine rotational speed Nt detected by the turbine rotational speed sensor 32 It means that the sign of change gradient is different. Since the determination result of the pseudo D state is cleared based on the sign of such a time change gradient, the determination accuracy is enhanced. In this case, it is determined that the rotational speed difference ΔNce at the time of determination in step S1 may have been generated due to a sensor abnormality, and the pseudo D control process is interrupted to shift to a sensor abnormality determination process. That is, when an abnormality in which the sensor output value gradually decreases occurs in the turbine rotational speed sensor 32, the determination is made based on the operating point in the drive state, and the sensor output value is gradually output to the turbine rotational speed sensor 32. When an ascending abnormality occurs, by making a determination based on the operating point in the coasting state, a state in which the operating direction of the operating point is clearly different can be detected, and the determination accuracy can be enhanced. Further, in the coast state, the determination accuracy can be improved by determining whether or not the operation area is an abnormal area based on whether or not the operating point exceeds Smax.

  FIG. 7 is determined based on the relationship between the primary rotation speed sensor 33 and the value obtained by converting the secondary rotation speed sensor 34 based on the transmission ratio of the belt-type continuously variable transmission 4 in the drive state where the accelerator pedal is depressed. Map. Even during the pseudo D control process, the primary rotation speed Npri has a one-to-one relationship with the transmission ratio reference primary rotation speed Npri (R), which is a value obtained by dividing the secondary rotation speed Nsec by the transmission ratio. Therefore, the primary rotation speed Npri and the transmission ratio reference primary rotation speed Npri (through the operation point determined by the relationship between the primary rotation speed Npri and the transmission ratio reference primary rotation speed Npri (R) at the time of starting the pseudo D control process Set a reference line that is proportional to R). Next, the low rotation threshold Smin is set on the low rotation speed side of the reference line, the high rotation threshold Smax is set on the high rotation speed side of the reference line, and a region surrounded by Smax and Smin is a normal region, otherwise Is defined as an abnormal area.

  For example, as shown in the lower part of the map of FIG. 7, when both the primary rotation speed sensor 33 and the secondary rotation speed sensor 34 are normal, the gear ratio reference primary rotation speed is increased with the increase of the primary rotation speed Npri. Since Npri also rises, the operating point should move obliquely upward within the range of the normal region. On the other hand, when an abnormality occurs in which the sensor output value gradually decreases in the primary rotation speed sensor 33, the operating point moves in a direction different from the direction considered to move at normal time, and falls below Smin and is within the abnormal area. Move to the state of “d” means the sign of the time change gradient of the primary rotation speed Npri detected by the primary rotation speed sensor 33 after determining that it is a pseudo D state, and the time of the secondary rotation speed Nsec detected by the secondary rotation speed sensor 34 It means that the sign of change gradient is different. Since the determination result of the pseudo D state is cleared based on the sign of such a time change gradient, the determination accuracy is enhanced. In this case, it is determined that the rotational speed difference ΔNce at the time of determination in step S1 may have been generated due to a sensor abnormality, and the pseudo D control process is interrupted to shift to a sensor abnormality determination process. Further, in the drive state, the determination accuracy can be improved by determining whether or not the operating area is an abnormal area based on whether or not the operating point falls below Smin.

FIG. 8 is determined based on the relationship between the primary rotation speed sensor 33 and the value obtained by converting the secondary rotation speed sensor 34 based on the transmission ratio of the belt-type continuously variable transmission 4 in the coast state where the accelerator pedal is released. Map. Even during the pseudo D control process, the primary rotation speed Npri has a one-to-one relationship with the transmission ratio reference primary rotation speed Npri (R), which is a value obtained by dividing the secondary rotation speed Nsec by the transmission ratio. The reference line, the low rotation threshold value Smin and the high rotation threshold value Smax are set in the same manner as in the case described in FIG.
For example, as shown in the lower part of the map of FIG. 8, when both the primary rotation speed sensor 33 and the secondary rotation speed sensor 34 are normal, the transmission ratio reference primary rotation speed Npri also decreases with the decrease of the primary rotation speed Npri. Therefore, the operating point should move toward the origin within the range of the normal region. On the other hand, when an abnormality occurs in which the sensor output value gradually increases in the primary rotation speed sensor 33, the operating point moves in a direction different from the direction considered to move at the normal time, exceeding Smax and within the abnormal area. Move to In this case, it is determined that the rotational speed difference ΔNce at the time of determination in step S1 may have been generated due to a sensor abnormality, and the pseudo D control process is interrupted to shift to a sensor abnormality determination process. Further, in the coast state, the determination accuracy can be improved by determining whether or not the operation area is an abnormal area based on whether or not the operating point exceeds Smax.

As described above, in the first embodiment, the following effects can be obtained.
(1) A clutch 3a disposed between the engine 1 (drive source) and the drive wheel 6;
A belt type continuously variable transmission 4 (automatic transmission) disposed between the clutch 3 a and the drive wheel 6;
A control valve 20 (hydraulic control means) that supplies a clutch engagement pressure Pcl to the clutch 3a via a manual valve 21 that operates in conjunction with the operation of the shift lever 40;
A turbine rotational speed sensor 32 (first sensor) that detects a turbine rotational speed Nt that is an input side rotational speed of the clutch 3a;
A primary rotation speed sensor 33 (second sensor) that detects a primary rotation speed Npri that is an output side rotation speed of the clutch 3a;
When the driver operates the shift lever to select the travel range, the rotational speed of the turbine rotational speed Nt detected by the turbine rotational speed sensor 32 and the primary rotational speed Npri detected by the primary rotational speed sensor 33 Pseudo D state determination result clear processing (pseudo D state determination means) that determines the pseudo D state in which switching of the manual valve 21 is insufficient when the difference ΔNce is equal to or greater than ΔN1 (first rotation speed difference);
Sensor abnormality determination processing (sensor abnormality detection means) that determines that the sensor is abnormal when the rotational speed difference between the turbine rotational speed sensor 32 and the primary rotational speed sensor 33 is ΔN2 (second rotational speed difference) or more larger than ΔN1;
Equipped with
In the pseudo D state determination result clear process, when it is determined that the sensor is abnormal after the pseudo D state is determined, the determination result of the pseudo D state is cleared.
Therefore, even after the determination as the pseudo D state, it is possible to detect the case where the pseudo D state is determined due to the sensor abnormality, and the determination result of the pseudo D state can be appropriately cleared.

(2) The torque converter 2 with the lockup clutch 2a disposed between the engine 1 and the clutch 3a
Lock-up clutch control means for releasing the lock-up clutch 2a when it is determined to be a pseudo D state, and for engaging the lock-up clutch 2a when the determination result of the pseudo D state is cleared;
An engine speed sensor 31 (third sensor) that detects an engine speed Ne;
Sensor abnormality determination processing (sensor abnormality detection means for detecting a sensor abnormality based on detection values of the turbine rotational speed sensor 32, the primary rotational speed sensor 33, and the engine rotational speed sensor 31 when the lockup clutch 2a is engaged )When,
Equipped.
Therefore, after it is determined to be the pseudo D state, it is possible to shift to the sensor abnormality determination process, and the sensor abnormality can be detected.

(3) The sensor abnormality determination process determines that the sensor is abnormal when (Nt-Npri), (Nt-Ne) and (Ne-Npri) are equal to or larger than ΔN2 (second rotation speed difference) larger than ΔN1.
Therefore, while performing the pseudo D control process at an early stage, it is possible to detect a stable sensor abnormal state.

(4) The abnormal area determination process (pseudo D state determination means) determines the pseudo D state and then uses the sign of the time change gradient of the engine rotational speed Ne detected by the engine rotational speed sensor 31 and the turbine rotational speed sensor 32 When the sign of the detected turbine rotational speed Nt is different from the sign with the time change gradient, the determination result of the pseudo D state is cleared.
Therefore, it is possible to accurately determine whether the sensor abnormality is the reason for determining the pseudo D state.

(5) A secondary rotation speed sensor 34 (fourth sensor) for detecting the secondary rotation speed sensor Nsec (output side rotation speed) of the belt-type continuously variable transmission 4 is provided,
The abnormal area determination process estimates the primary rotation speed Npri (R) based on the gear ratio of the belt-type continuously variable transmission 4 and the secondary rotation speed Nsec detected by the secondary rotation speed sensor 34 after determining that it is a pseudo D state. If the sign of the time change gradient of primary rotation speed Npri detected by primary rotation speed sensor 33 is different from the sign of the time change gradient of estimated transmission ratio reference primary rotation speed Npri (R), the pseudo D state Clear the judgment result of.
Therefore, it is possible to accurately determine whether the sensor abnormality is the reason for determining the pseudo D state.

[Other embodiments]
As mentioned above, although the form for implementing this invention was demonstrated based on the Example, the specific structure of this invention is not limited to the structure shown in the Example, It is a range which does not deviate from the summary of invention. Even if there is a design change etc., it is included in the present invention. In the first embodiment, an engine is shown as the drive source, but the invention is not limited to the engine, and may be a hybrid vehicle using an electric motor in combination or an electric vehicle having only an electric motor. Moreover, although the belt type continuously variable transmission 4 was shown as a transmission, it may be another stepped automatic transmission.

  In the first embodiment, an example is shown in which the sensor abnormality is detected separately for the drive state and the coast state in the abnormal area determination processing, but for example, if the engine torque reduction is being performed even in the drive state The operating point may be determined using the maps of FIG. 6 and FIG. 8 in order to move in the same manner as the coasting state. Also, instead of the secondary rotation speed sensor 34, based on the detection value of the wheel speed sensor 35, in consideration of the gear ratio of the differential gear 5 and the transmission ratio of the belt type continuously variable transmission 4, transmission ratio reference primary rotation speed Npri (R) May be calculated.

Reference Signs List 1 engine 2 torque converter 2a lockup clutch 3 forward / reverse switching mechanism 3a clutch 4 belt type continuously variable transmission 4a primary pulley 4b belt 4c secondary pulley 5 differential gear 6 drive wheel 10 engine output shaft 11 turbine shaft 12 input shaft 13 output shaft Reference Signs List 20 control valve 21 manual valve 31 engine speed sensor 32 turbine speed sensor 33 primary speed sensor 34 secondary speed sensor 35 drive shaft 35 wheel speed sensor 36 inhibitor switch 37 APO sensor 40 shift lever

Claims (5)

A clutch disposed between the drive source and the drive wheel,
An automatic transmission disposed between the clutch and the drive wheel;
Hydraulic control means for supplying an engagement pressure to the clutch via a manual valve operated in conjunction with the operation of the shift lever;
A first sensor that detects an input side rotational speed of the clutch;
A second sensor that detects an output side rotational speed of the clutch;
When the driver operates the shift lever to select the travel range, the rotation of the input-side rotational speed of the clutch detected by the first sensor and the output-side rotational speed detected by the second sensor Pseudo D state determination means for determining a pseudo D state in which switching of the manual valve is insufficient when the number difference is equal to or greater than the first rotation speed difference;
Sensor abnormality detection means for judging as sensor abnormality when the rotational speed difference between the first sensor and the second sensor is equal to or larger than a second rotational speed difference larger than the first rotational speed difference;
Equipped with
The control of the automatic transmission characterized in that the pseudo D state determination means clears the determination result of the pseudo D state when the sensor abnormality detection means determines that the sensor abnormality is detected after the pseudo D state determination. apparatus. In the control device for an automatic transmission according to claim 1,
A torque converter with lockup clutch disposed between the drive source and the clutch;
Lock-up clutch control means for releasing the lock-up clutch when it is determined to be in the pseudo D state, and for engaging the lock-up clutch when the determination result in the pseudo D state is cleared;
A third sensor that detects a drive source rotational speed of the drive source;
Sensor abnormality detection means for detecting a sensor abnormality based on detection values of the first, second and third sensors when the lockup clutch is engaged;
A control device for an automatic transmission, comprising: In the control device for an automatic transmission according to claim 2,
The sensor abnormality detection means includes a difference in rotational speed between the first sensor and the second sensor, a difference in rotational speed between the first sensor and the third sensor, and a rotational speed between the second sensor and the third sensor. A control device for an automatic transmission characterized in that the sensor abnormality is judged when the difference is equal to or more than a second rotation speed difference larger than the first rotation speed difference. In the control device for an automatic transmission according to any one of claims 2 to 3,
The pseudo D-state determining means determines that it is the pseudo D-state, the sign of the temporal change gradient of the drive source rotational speed detected by the third sensor, and the time of the input side rotational speed detected by the first sensor The control device for an automatic transmission, wherein the determination result of the pseudo D state is cleared when the sign of the change gradient is different from the sign of the change slope. The control device for an automatic transmission according to any one of claims 1 to 5,
It has a fourth sensor for detecting the output side rotational speed of the automatic transmission,
The pseudo D state determination means estimates the output side rotational speed of the clutch based on the transmission gear ratio of the automatic transmission and the rotational speed detected by the fourth sensor after determining the pseudo D state, and If the sign of the temporal change gradient of the output side rotational speed detected by the two sensors is different from the sign of the temporal change gradient of the estimated output side rotational speed, clear the determination result of the pseudo D state Control device of automatic transmission characterized by the above.

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