JP2005024509A - Method of diagnosing failure for torque sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a select assist system of an automatic transmission, capable of realizing expansion of layout flexibility by reducing the size of a select lever, and capable of obtaining the characteristics of the operating force for a select lever, responding to demands, while ensuring reliability by the mechanical coupling with the selecting lever and the switching system of a range position. <P>SOLUTION: An electric motor 15 assist for driving the select lever 2 is provided; an elastic portion 219 is provided adjacent to the end of a P range in the ranges of the P range to an L range of the select lever 2; the select lever 2 is pressed against the elastic portion 219 by driving the electric motor 15, when the select lever 2 is in the P range; and the abnormality of a torque sensor 21 is examined by whether estimated torque is output by a torque sensor 21 by providing the select lever 2 reaction force. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention belongs to a technical field of a failure diagnosis method for a torque sensor that detects an operation force input to an operation system, and particularly an automatic transmission that assists a driver's select lever operation force in a vehicle equipped with an automatic transmission. This is useful for select assist devices.

  Conventionally, when the zero point is corrected to diagnose whether the torque value based on the signal from the torque sensor is correct, if the value calculated for the correction exceeds the specified value, it is determined that the zero point or more is exceeded. (For example, refer to Patent Document 1).

  Conventionally, the select lever of the automatic transmission is mechanically connected to the manual valve of the automatic transmission via an operating force transmission means such as a rod or cable. The operating force of the driver input to the select lever is transmitted to the manual valve via the operating force transmission means, and the range position is switched according to the operation amount (see, for example, Patent Document 2).

On the other hand, what uses what is called shift-by-wire technique in which the select lever and the manual valve are electrically connected is known. In this prior art, an actuator that operates a manual valve is provided, and the range position is switched by driving the actuator by changing the rotation operation of the select lever into an electric signal (see, for example, Patent Document 3).
Japanese Patent No. 2803966 Japanese Patent Laid-Open No. 9-323559 JP 2003-97694 A

  Conventionally, only the zero point abnormality is determined by comparing the zero point correction value calculated based on the torque value detected from the torque sensor signal with the set threshold value, so that the intermediate level ( Torque value abnormality detection and judgment could not be made in the use area. In addition, since only the zero point abnormality is detected, there is a problem that no abnormality occurs (zero point correction is performed) if it is within the normal use region. In addition, there is a problem that it is impossible to determine whether the value at the time of torque generation for detecting only the zero point abnormality is normal.

  On the other hand, when the select lever of the conventional automatic transmission is operated, a mechanical operation reaction force such as friction of the operating force transmission means and resistance of detent is generated, so that a large operating force is required. Therefore, in order to reduce the necessary operating force of the driver, it is necessary to set the length of the select lever to a length that can obtain a sufficient lever force.

  Therefore, in the former of the conventional automatic transmission technologies, the former has a large shape due to the length of the select lever, so there are many restrictions on the installation location and the degree of freedom in layout in the vehicle interior is low. was there.

  On the other hand, in the latter, the selection lever can be designed shorter by adopting the actuator, and the degree of freedom in layout becomes higher than that in the former. However, since the select lever and the manual valve are not mechanically connected, the range cannot be switched during a failure. Therefore, there are problems in terms of reliability and safety.

  The present invention has been made paying attention to the above problems, and an object of the present invention is to provide a torque sensor failure diagnosis method capable of determining whether an output value with respect to torque applied to the torque sensor is correct. In addition, it is equipped with a torque sensor that maintains an accurate output value by this failure diagnosis method. By ensuring the reliability by mechanical connection of the select lever and the range position switching device, the select lever can be downsized. It is an object of the present invention to provide a selection assist device for an automatic transmission that can increase the degree of layout freedom and can obtain a select lever operating force characteristic according to demand.

  In order to achieve the above object, in the torque sensor failure diagnosis method according to claim 1 of the present invention, in the torque sensor for detecting the operation force input to the operation system, a diagnosis motor for driving the operation system is provided, An elastic part is provided in the vicinity of the movable range end of the movable part of the operation system, and when the movable part of the operational system is at the movable range end, the diagnostic motor is driven to move the movable part of the operational system. The elastic portion is pressed against the elastic portion to elastically deform, and a reaction force is applied to an operation system so that the abnormality of the torque sensor is diagnosed by whether or not the torque sensor outputs a predetermined torque. To do.

  According to a second aspect of the present invention, in the torque sensor failure diagnosis method according to the first aspect, a torque sensor that detects an input operation force to a select lever connected to a range position switching device of an automatic transmission, and the select Based on the detected input operation force and the operation position, the operation position detection means for detecting the operation position of the lever, the assist motor for outputting the assist force for assisting the operation force of the driver to the select lever, In an automatic transmission select assist device having an assist force control means for outputting a control command for changing an assist force, the end of the movable range is set to the P range, and the select lever is pressed from the P range to the elastic portion. The assist motor that doubles as a motor is driven to diagnose the abnormality of the torque sensor. And butterflies.

  According to a third aspect of the present invention, in the torque sensor failure diagnosis method according to the first aspect, a torque sensor that detects an input operation force to a select lever that is interlocked without being connected to a range position switching device of an automatic transmission; An operation position detecting means for detecting an operation position of the select lever; a range position detecting means for detecting a range position of the range position switching device; and a resistance generating motor for giving an appropriate operating resistance and moderation to the select lever. A control command for changing the resistance force with respect to the resistance-sensing motor based on the detected input operation force and operation position. And the range position is switched for the switching actuator based on the operation position and range position. And a control means for outputting a control command, wherein the movable range end is a P range, and a resistance generating motor that doubles as a diagnostic motor to press the select lever from the P range to the elastic portion Is used to diagnose an abnormality of the torque sensor.

  According to a fourth aspect of the present invention, in the torque sensor failure diagnosis method according to the second or third aspect, the operation position detection means detects the amount of movement of the select lever at the time of abnormality diagnosis of the torque sensor, A deformation amount of the elastic part is calculated from the movement amount, and a predetermined torque to be detected by a torque sensor is calculated from a characteristic of the elastic force with respect to the deformation amount of the elastic part.

  According to a fifth aspect of the present invention, in the torque sensor failure diagnosis method according to the first to fourth aspects, the abnormality diagnosis of the torque sensor is performed without any input to the operation system. To do.

  According to a sixth aspect of the present invention, in the torque sensor failure diagnosis method according to the second to fifth aspects, the operation speed is detected from the operation position of the operation position detecting means, and the select lever is stopped from the operation speed. If it is determined that the torque sensor is abnormal, an abnormality diagnosis of the torque sensor is performed.

  According to a seventh aspect of the present invention, in the torque sensor failure diagnosis method according to the second to fifth aspects, if it is determined from the output value of the torque sensor that the select lever is stopped, the abnormality determination of the torque sensor is performed. It is characterized by having done.

  According to the first aspect of the present invention, the diagnostic motor is driven to press the movable part of the operation system against the elastic part. Then, the elastic part is elastically deformed and torque is applied to the movable part of the operation system as a reaction force thereof, so that the torque is measured by the torque sensor. Therefore, it can be determined from this torque value whether there is any abnormality in the torque sensor.

According to the second aspect of the present invention, in the select assist device for an automatic transmission having a torque sensor capable of maintaining an accurate output using the above-described diagnosis method, the mechanical connection between the select lever and the range position switching device is maintained. On the other hand, by assisting the driver's lever operating force with the assist actuator, it is possible to achieve both ensuring reliability and increasing layout flexibility by reducing the size of the select lever.
Further, it is possible to reliably diagnose abnormality of the torque sensor without providing another device around the select lever.

  In the invention according to claim 3, in the selection device for an automatic transmission having a torque sensor capable of maintaining an accurate output using the above-described diagnostic method, the selection lever and the range position switching device are only electrically connected. Therefore, it is possible to reduce the size of the select lever and further increase the flexibility of layout.

  According to the fourth aspect of the present invention, the amount of deformation of the elastic portion is calculated from the amount of movement of the select lever when the diagnostic motor is driven in the abnormality diagnosis of the torque sensor. Since the elastic portion is elastically deformed, its characteristics are clear in advance, and if the amount of elastic deformation is known, an elastic force as a reaction force to the select lever can be obtained. Further, if the reaction force to the select lever is obtained, the torque is calculated from the shape of the select lever. By comparing the torque value thus calculated with the torque value detected by the torque sensor, an abnormality of the torque sensor can be detected. Thus, the ability to detect an abnormality in the torque sensor without providing a separate detection device also reduces costs.

  In the fifth aspect of the invention, the abnormality diagnosis can be prevented from affecting the normal operation by judging the abnormality without any input to the operation system, and the abnormality diagnosis is affected by the operation. It can be done without.

  In the invention according to claim 6, when the operation speed is zero or close to zero, it may be determined that the operation is not performed. Therefore, the abnormality diagnosis is performed in this state, and the abnormality diagnosis is performed in a normal operation. The abnormality diagnosis can be performed without being affected by the operation.

  In the invention according to claim 7, when the output value from the torque sensor is a very small value, it can be determined that the operating force is not applied, and when the operating force is not applied, the operation is not performed. Therefore, the abnormality diagnosis can be performed in this state so that the abnormality diagnosis does not affect the normal operation, and the abnormality diagnosis is not affected by the operation.

  Embodiments for realizing a torque sensor failure diagnosis method of the present invention and a selection assist device for an automatic transmission equipped with the torque sensor using the diagnosis method will be described below based on examples.

First, the configuration will be described.
FIG. 1 is a side view showing the configuration of the automatic transmission apparatus according to the first embodiment, and FIG. 2 is a perspective view of the main part showing the detailed structure of the assist actuator.

  The automatic transmission apparatus according to the first embodiment has a select mechanism unit 1, a control cable 8, an assist actuator 9, a control cable 18, an automatic transmission 19, and a control unit (control means) 22 as main components. Yes.

  The selection mechanism unit 1 has a selection lever 2 that is operated by a driver, and is provided, for example, in a center cluster 3 beside the driver's seat. At the upper end of the select lever 2, a select knob 4 is attached for the driver to hold during the select operation. The select lever 2 is rotated about the fulcrum shaft 5 and is set to 100 mm, which is 250 mm shorter than a conventional general select lever.

  A push-pull control cable 8 is connected to the lower end of the select lever 2 via a select lever joint 7. The control cable 8 is rotatably connected to the input lever 10 of the assist actuator 9 via the input lever joint 11. That is, the rotational movement of the select lever 2 is converted into a linear movement, and the operating force generated by the operation of the select lever 2 is transmitted to the input lever 10.

  The input lever 10 is connected to an output lever 13 via an output shaft 12 that is rotatably provided. The output shaft 12 is provided with a worm gear 14, which meshes with a motor output shaft 16 of an electric motor (an assist motor, which is a diagnostic motor) 15 having a speed reduction mechanism.

  A push-pull control cable 18 is connected to the output lever 13 via an output lever joint 17. The control cable 18 is connected to the control arm 20 of the automatic transmission 19. That is, the rotational movement of the output lever 13 is converted into a linear movement by the control cable 18, and the combined force of the driver's operating force and the driving force of the electric motor 15 is transmitted to the control arm 20 of the automatic transmission 19.

  The output shaft 12 is provided with a torque sensor (input operation force detection means) 21 that detects distortion (twist) generated between the input lever 10 and the worm gear 14. The operation force signal detected by the torque sensor 21 is amplified by an amplification amplifier (not shown) and transmitted to the control unit 22 via the wire harness 23. Based on the detection signal of the torque sensor 21, the operation force in the select lever operation can be estimated.

  A contact 24 for position detection is attached and fixed to the worm gear 14. The contactor 24 rotates integrally with the worm gear 14 and makes electrical contact with a carbon resistor printed on a substrate (not shown), thereby outputting a voltage signal corresponding to the stroke angle of the select lever 2 to the control unit 22. . The contactor 24 and the carbon resistance constitute a potentiometer (operation position detecting means) 25.

  The potentiometer 25 detects the stroke angle of the select lever 2 at any time with the angle when the select lever 2 is stopped at the P range position as the base point angle.

  The control unit 22 sets a target assist force based on the detected stroke angle of the select lever 2 and the operation force of the driver, and performs PWM control on the output duty ratio of the electric motor 15.

As shown in FIG. 11, an elastic portion 219 is provided in the vicinity of the P range which is the range position at one end of the select mechanism portion 1. The elastic portion 219 includes a coil spring 219a whose one end is fixed to the fixed end portion 218, and a receiving portion 219b which is attached to the coil spring 219a and serves as a portion to which the select lever 2 abuts.
The coil spring 219a is attached to a recess provided in the fixed end 218 so as to protrude from the fixed end 218. When the receiving portion 219b comes into contact with the fixed end 218, the coil spring 219a is not further compressed and is seated. Prevent bending.

FIG. 3 shows a control block diagram of the control unit 22.
The change in the stroke of the select lever 2 that has been subjected to the range switching operation in the select mechanism unit 1 is input to the potentiometer 25 of the assist actuator 9 via the control cable 8. The potentiometer 25 detects a stroke angle corresponding to the operation amount of the select lever 2 and outputs it to the control unit 22 as a stroke angle signal.

  Further, the operating force of the select lever 2 is input to the torque sensor 21 of the assist actuator 9 via the control cable 8. The torque sensor 21 detects the operation force of the select lever 2 and outputs it to the control unit 22 as an operation force signal.

  The output value of the torque sensor 21 is first input to the drift correction block 50 of the control unit 22. In this drift correction block 50, the operation speed of the select lever 2 from the differentiator 51 and the range stop position information from the position / operation start / direction discrimination block 33 are obtained, and the select lever 2 is stopped at the range stop position. In some cases, the zero correction of the torque sensor 21 is performed, and the corrected operation force signal is output to the adder 35, the position / operation start / direction determination block 33, and the torque value diagnosis block 52.

The position / operation start / direction discriminating block 33 determines the current stroke angle of the select lever 2 based on the stroke angle signal. Further, the operation start, the operation direction, the operation speed, and the operation acceleration of the select lever 2 are determined from the stroke angle signal, the differential value of the stroke angle signal, and the operation force signal, and the determination results are obtained from the FF compensation table 43 and the target table block 34. Output to the motor drive control block 45.
The differentiator 51 differentiates the stroke angle signal from the potentiometer 25 to calculate the operation speed, and outputs the operation speed to the position / operation start / direction determination block 33, the drift correction block 50, and the torque value diagnosis block 52.

  In the torque value diagnosis block 52, when the select lever 2 is located at the P range position and is not operated, an inspection drive signal is output and a current is supplied to the electric motor 15, and the select lever 2 is moved in the direction opposite to the R range direction. The torque sensor is diagnosed with the torque value that has been pressed, and if it is abnormal, an abnormality signal is output to the failure diagnosis block 53 (only when IGN is ON).

In the failure diagnosis block 53, it is determined whether or not the torque value at the time of test driving input from the torque value diagnosis block 52 is within a predetermined value range, and if abnormal, an abnormal stop signal is transmitted to the motor drive control. In addition to outputting to block 45, a failure alarm signal is output.
The calculation of the predetermined value range of the torque value is performed as follows. From the stroke angle signal obtained from the potentiometer 25, the amount of movement of the select lever 2 at the time of diagnosis is calculated, the amount of deformation of the elastic portion 219 is calculated from the amount of movement, and the reaction force is calculated from the relationship between the amount of deformation of the coil spring 219b and the spring load. And a torque value is calculated from the shape of the select lever 2 to determine a predetermined range of the torque value.

  In the target table block 34, the target operation reaction force corresponding to the stroke angle of the select lever 2 is calculated from the stroke angle signal and the operation direction of the select lever 2 obtained by the position / operation start / direction determination block 33. It is output to the adder 35.

  Here, since the target operation reaction force varies depending on the stroke angle of the select lever 2, the target operation reaction force for each stroke angle is stored in a table in the target table block 34.

  The adder 35 calculates a deviation between the operation force signal and the target operation reaction force, and outputs the calculation result to the FB control unit 36.

  The FB control unit 36 includes a multiplier 37, an adder 38, a multiplier 39, and an integrator 40. The multiplier 37 outputs a value obtained by multiplying the deviation between the operation force signal and the target operation reaction force by a proportional gain to the adder 38 (proportional output). The multiplier 39 outputs a value obtained by multiplying the deviation between the operation force signal and the target operation reaction force by an integral gain to the integrator 40. The integrator 40 integrates the output of the multiplier 39 and outputs it to the adder 38 (integration output). The adder 38 outputs a feedback assist force that is the sum of the proportional output and the integral output to the adder 41.

  The FF controller 42 includes an FF compensation table block 43 and a multiplier 44. The FF compensation table block 43 outputs preset values corresponding to the stroke angle signal, the operation speed, and the operation acceleration to the multiplier 44. The multiplier 44 outputs a value obtained by multiplying the FF assist force by the FF gain, that is, a feed forward assist force to the adder 41.

  The adder 41 outputs the output sum (feedback assist force + feedforward assist force) of the FB control unit 36 and the FF control unit 42, that is, the target assist force, to the motor drive control block 45.

  A motor drive control block (corresponding to an assist force control unit) 45 drives the electric motor 15 based on the target assist force.

Next, the detent structure of the automatic transmission 19 will be described.
FIG. 4 is a perspective view showing a detent structure of the automatic transmission 19.
The control arm 20 is provided with a rotation shaft 26, and a detent plate 27 is supported on the rotation shaft 26. At the upper end of the detent plate 27, a valley portion 27b corresponding to five ranges (P, R, N, D, and L) is formed between the cam peaks 27a. Then, the detent pin 29 formed at the tip of the spring plate 28 is engaged with the valley portion 27b and the selected range position is maintained, thereby preventing an unintended range select due to vehicle vibration or the like. Yes.

  That is, the rotating shaft 26 is rotated by the operating force of the select lever 2, and the detent plate 27 is moved relative to the detent pin 29 in accordance with the rotation. At this time, the detent pin 29 gets over the cam crest 27 a and engages with the valley portion 27 b corresponding to the adjacent range, and the engaged state is held by the elastic force of the spring plate 28. This elastic force becomes a main load force when the select lever 2 is operated.

  Note that one end of the parking pole 30 is rotatably connected to the detent plate 27. When the select lever 2 is moved to the P range, the parking pole 30 prevents rotation of the parking gear 32 via the cam-like plate 31 and locks driving wheels (not shown). Thereby, when the vehicle is parked on the slope road in the P range, a vehicle load is applied so as to lock the driving wheel according to the slope, and acts as a force for biting the parking pole 30.

  In the first embodiment, a magnetostrictive torque sensor is used as the torque sensor 21 (input operating force detection means) as shown in FIG. In this magnetostrictive torque sensor, when a torque is applied to the shaft 211, the shaft 211 is twisted, and tensile stress and compressive stress are selectively applied to the two portions grooved in the opposite direction to the shaft 211, respectively. The magnetic permeability of this part increases / decreases due to the magnetostrictive effect. The magnetic permeability change due to the inverse magnetostriction effect is generated by the exciting coil 212 with respect to the shaft 211, the magnetic field of the shaft 211 whose magnetic permeability is changed is detected by the two detection coils 213, and the detected voltage waveform is generated by the rectifier 214. Rectified and DC converted by a smoother 215. Thereafter, differential amplification is performed by the adder 216 and the amplifier 217 to obtain a voltage output proportional to the torque.

Next, the operation will be described.
[Select lever assist control processing]
FIG. 5 is a flowchart showing a flow of assist control processing of the select lever 2 executed by the control unit 22.

  In step S1, the operation force is read from the operation force signal of the torque sensor 21, and the process proceeds to step S2.

  In step S2, the stroke angle is read from the stroke angle signal of the potentiometer 25, and the process proceeds to step S3.

  In step S3, the operation direction of the select lever 2 is calculated from the stroke angle of the select lever 2 and the increase / decrease difference between the stroke angles read in the previous control cycle, and the process proceeds to step S4.

  In step S4, the operation speed of the select lever 2 is calculated from the stroke angle of the select lever 2 and the change rate of the stroke angle read in the previous control cycle, and the operation acceleration of the select lever 2 is calculated from the differential value of the operation speed. Then, the process proceeds to step S5.

  In step S5, an FF compensation table reading process is performed, and the process proceeds to step S6. The optimum FF compensation table is selected from a plurality of preset tables according to the stroke angle, the operation speed, and the operation acceleration.

  In step S6, target table reading processing is performed, and the process proceeds to step S7.

  In step S7, the FF assist force is set from the read FF compensation table, and the process proceeds to step S8.

  In step S8, the FB assist force is set from the read target table, and the process proceeds to step S9.

  In step S9, a target assist force is set from the sum of the set FF assist force and FB assist force, and the process proceeds to step S10.

  In step S10, the output duty ratio of the electric motor 15 is controlled so as to achieve the target assist force.

  In step S11, a diagnosis process for the torque sensor is performed, and this control is terminated.

[Operation reaction force characteristics of automatic transmission]
FIG. 6 is a characteristic diagram showing an operation reaction force generated in the select lever 2 in the P → R range direction, more precisely, the select knob 4 held by the driver. This operation reaction force characteristic is an axis detected as an operation reaction force on the output shaft 12 of the assist actuator 9 when the driver operates the select lever 2 in the P → R range direction without driving the electric motor 15. The torque is converted as an operation reaction force Fm [N] generated in the select knob 4 and compared with the stroke angle acquired by the potentiometer 25.

  This operation reaction force is a combination of the load force generated by the detent of the automatic transmission 19 described above and the frictional force of the control cables 8 and 18 and the inertia of the electric motor 15. That is, in order to switch the range in the absence of the assist force by the electric motor 15, a manual operation force greater than the operation reaction force Fm is required.

  As shown in FIG. 6, the operation reaction force Fm generated when the select lever 2 is operated in the P → R range direction is initially opposite to the operation direction of the select lever 2 (D → N range) between the ranges. Direction), changes direction after the peak, occurs in the same direction as the operation direction (P → R range direction), and converges to zero near the range switching position (stop position). This characteristic is caused by the load force generated when the detent pin 29 gets over the cam crest 27 a of the detent plate 27. That is, until the detent pin 29 gets over the cam mountain 27a, a resistance force is generated by the urging force of the spring plate 28. After the detent pin 29 gets over the cam mountain 27a, the detent pin 29 moves to the next cam mountain 27a. This is because a pulling force (inertial force) is generated by falling into the groove.

[Target operation reaction force characteristics]
FIG. 7 is a characteristic diagram showing the target operation reaction force of the select lever 2 in the P → R range direction. This target operation reaction force characteristic is obtained by setting in advance a target operation reaction force Ft [N] that provides a favorable operation characteristic with a sense of moderation for the driver according to the stroke angle of the select lever 2.

[FF control assist force map]
FIG. 8 is an assist force map in the P → R range direction in the FF control. In this assist force map, an operation force that is approximately ½ of the detent operation reaction force in FIG. 6 is assisted by the FF control in accordance with the stroke angle of the select lever 2.

[FF control + FB control]
In the embodiment, the assist force is set to a deviation between the feed forward assist force Fff [N] set so as to be about half the detent operation reaction force and the actual operation force and the target operation reaction force Ft. By using two components of the feedback assist force FFb [N] that is set based on this, it is possible to achieve both a high level of response and disturbance suppression in assist control of a select lever with a steep and large torque deviation. Operation characteristics can be realized.

[Necessity for diagnosis of torque sensor output value]
Here, the necessity for diagnosis of the torque sensor output value will be described. When an abnormality occurs in the output value of the torque sensor 21, if the output of the torque sensor 21 exceeds the specified value with respect to the operation force to the select lever 2, an assist force is generated more than necessary when the select lever 2 is operated. Then, the phenomenon that the select lever 2 moves without permission occurs. Further, when the output of the torque sensor 21 becomes smaller than a specified value with respect to the operation force of the select lever 2, a necessary assist force is not generated when the select lever 2 is operated, and a phenomenon that the select lever 2 becomes heavy occurs. .
In particular, when the output of the torque sensor 21 is larger than a specified value with respect to the operating force of the select lever 2, an assist force is generated more than necessary. Hunting phenomenon that vibrates back and forth easily occurs during the operation of the select lever 2 or at a mechanically fixed position, increasing the degree of danger and discomfort.
On the other hand, in the torque sensor failure diagnosis method of the first embodiment and the automatic transmission select assist device equipped with the torque sensor using this diagnosis method, a torque value diagnosis block 52 and a failure diagnosis block 53 are provided. Yes.

[Flow of torque sensor failure diagnosis]
FIG. 9 is a flowchart showing a flow of a torque sensor failure diagnosis process executed by the control unit 22.

  In step S101, this process is started when IGN is ON.

  In step S102, it is determined whether or not the operation position of the select lever 2 is in the P range. If it is in the P range, the process proceeds to step S103, and if not in the P range, the process proceeds to step S108 to perform normal processing. Like that.

  In step S103, it is determined from the operation speed from the differentiator 51 whether or not an operation is currently being performed. If there is no operation, the process proceeds to step S104, and if there is an operation, the process proceeds to step S108. Shift to normal processing.

  In step S <b> 104, a predetermined current value determined in advance is caused to flow through the electric motor 15 to be inspected and the select lever 2 is pressed against the elastic portion 219.

  In step S <b> 105, the reaction force that presses the select lever 2 against the elastic portion 219 is detected by the torque sensor 21.

  In step S106, driving of the electric motor 15 for inspection driving is stopped.

  In step S107, it is determined whether or not the output value of the torque sensor 21 by inspection driving is normal. If normal, the process proceeds to step S108, and if abnormal, the process proceeds to step S109.

  In step S108, normal assist processing is performed as normal.

  In step S109, an assist control stop signal is output to the motor drive control block 45 as abnormal, and the assist control is stopped.

[Torque sensor diagnosis]
<1> Normal processing After the IGN is turned ON, if the operation position of the select lever 2 is other than the P range or is being operated, the processing returns to the normal assist processing without performing diagnosis of the torque sensor by the processing of steps S102 and S103. To.
When the operation position of the select lever 2 is in the P range and no operation is performed, the electric motor 15 causes the select lever 2 to be provided in the opposite direction from the P range to the R range, that is, in a fixed end member. The portion 219 is pressed with a predetermined drive current value and drive torque that are within the elastic range of the coil spring 219a. Then, the coil spring 219a of the elastic part 219 is elastically deformed (see FIG. 11). Accordingly, the select lever 2 moves, and the amount of movement is detected by the potentiometer 25. Therefore, the repulsive elastic force is calculated by the spring constant from the compression amount of the coil spring obtained from the movement amount of the select lever 2, and the torque as the reaction force received by the select lever 2 at that time is calculated from the shape of the select lever 2. Can be sought. The torque sensor 21 detects the driving torque or the torque obtained by subtracting the loss obtained in advance through experiments or the like (steps S104 to S106).

  As a result of the determination process in step S107, if the torque value is normal, the torque sensor 21 is assumed to be normal and a normal assist process is performed.

<2> Abnormal processing When there is an abnormality in the torque sensor 21, the output of the torque value for the elastic force generated by the driven electric motor 15 is too large or too small. In step S109, a control stop signal is output to the motor drive control block 45, and the assist control is stopped.
In this state, although the operation of the select lever 2 becomes heavy, it is set in a state where it can be manually operated, and processing on the safe side is performed so as not to cause further malfunction.

Next, the effect will be described.
The torque sensor failure diagnosis method of the present embodiment and the automatic transmission select assist device provided with the torque sensor using this diagnosis method can provide the following effects.

  (1) In the torque sensor 21 that detects the operation force input to the operation system, an electric motor 15 that assists the select lever 2 is provided, and is close to the end of the P range from the P range to the L range of the select lever 2. The fixed end 218 is provided with an elastic portion 219. When the select lever 2 is in the P range, the electric motor 15 is driven, the select lever 2 is pressed against the elastic portion 219, and a reaction force is applied to the select lever 2. Since the abnormality of the torque sensor 21 is diagnosed by whether or not the torque sensor 21 outputs a predetermined torque, the abnormality of the shaft 211 of the torque sensor 21 such as a change in magnetic characteristics due to an impact or an overload, Parts of the torque detection electronic component due to coil abnormalities such as partial shorts of the excitation coil 212 and the detection coil 213, incorrect installation, aging, overload, etc. It can be determined without abnormality and the like may be added to another device whether there torque sensor 21.

(2) The select lever 2 has a projection amount of about 150 mm less than the conventional select lever, and the select lever 2 and the control arm 20 are connected via control cables 8 and 18. The degree of freedom of the interior layout of the vehicle is greater than that of the product, and the select lever 2 can be set at an arbitrary position in the vehicle interior such as an instrument panel.
Further, since the select lever 2 and the control arm 20 are mechanically connected by the control cables 8 and 18, even when the assist actuator 9 or the control unit 22 fails, the driver can manually switch the range position. Safety can be secured.
Further, since the electric motor 15 is driven so as to press the select lever 2 against the fixed end 218 from the P range and the abnormality of the torque sensor 21 is diagnosed, the torque sensor is not provided around the select lever 2. 21 abnormalities can be reliably diagnosed.

  (4) The amount of movement of the select lever 2 at the time of abnormality diagnosis of the torque sensor 21 is detected by the potentiometer 25, the amount of deformation of the elastic portion 219 is calculated from the amount of movement, and the characteristic of the elastic force with respect to the amount of deformation of the elastic portion 219 Since the torque to be detected by the torque sensor 21 is calculated from the above, it is possible to confirm whether there is no abnormality in the torque sensor easily and in a short time by the elastic characteristics of the spring without providing a separate device. Further, since the diagnosis can be performed without burden on the operation of the select lever 2, the diagnosis can be performed many times and the torque sensor can be managed more reliably.

  (5) Since the abnormality diagnosis of the torque sensor 21 is performed without any input to the select lever 2, the abnormality diagnosis can be prevented from affecting normal operation, and the abnormality diagnosis is affected by the operation. It can be done without.

  (6) Since the operation speed is detected from the operation position of the potentiometer 25 and it is determined from the operation speed that the select lever 2 is stopped, the abnormality of the torque sensor 21 is diagnosed, so the operation speed is zero or close to zero. In this case, since it may be determined that the operation is not performed, the abnormality diagnosis is performed in this state so that the abnormality diagnosis does not affect the normal operation and the abnormality diagnosis is affected by the operation. It can be done without.

The second embodiment is an example of a torque sensor failure diagnosis method in a selection device for an automatic transmission that does not mechanically connect the select lever and the automatic transmission.
First, the configuration will be described.
FIG. 13 is a side view showing the configuration of the automatic transmission of the second embodiment, and FIG. 14 is a control block diagram of the control unit 22.

  In the second embodiment, the select lever 2 and the control arm of the automatic transmission 19 are not mechanically connected and the range is switched.

The automatic transmission apparatus according to the second embodiment includes a select lever side that detects an operation on the select lever 2, a switching actuator side that switches a range between the automatic transmission 19 and the automatic transmission 19, and a control unit 22 (control means). Main structure.
In addition to the detent structure of the automatic transmission 19, a detent plate 81 that is attached to the rotating shaft of the select lever 2 and rotates and displaces is provided on the select lever side, as shown in FIG. The detent plate 81 is provided with a cam peak 81a and a valley part 81b, and the detent pin 83 is engaged with the cam peak 81a and the valley part 81b so as to be pressed by the urging force of the spring plate 82. The valley portion 81b of the detent plate 81 corresponds to the P range, R range, N range, D range, and L range, and has a structure that can be operated with a force smaller than the detent force of the automatic transmission 19.
Further, the select lever 2 includes a potentiometer 61 for detecting the operation position of the select lever 2 and an electric motor 62 (corresponding to a resistance generation motor) that generates a resistance feeling of the operation of the select lever 2 in addition to the detent force by the detent plate 81. ), A torque sensor 60 for detecting the input operation force of the select lever 2 is provided.

  The outputs of the torque sensor 60 and potentiometer 61 on the select lever side are sent to the control unit 22, and the wire harness 23 is connected so that the electric motor 62 is controlled and driven by the control unit 22.

Next, an electric motor 63 in which a control arm 20 for switching the range position of the automatic transmission 19 is mechanically connected by a control cable 18 is provided on the automatic transmission side. Specifically, the end of the output lever 13 provided on the rotating shaft 64 rotated by the motor output shaft 631 of the electric motor 63 is attached to the control cable 18 by the output lever joint, so that the control arm 20 is operated by the electric motor 63. Switch the range. A potentiometer 65 for detecting a range switching position is provided on the rotating shaft 64 portion of the electric motor 63.
The output of the potentiometer 65 on the automatic transmission side is input to the control unit 22, and the electric harness 63 is connected by the wire harness 23 so as to be controlled by the control unit 22.

FIG. 14 shows a control block diagram of the control unit 22 of the second embodiment.
On the select lever side, the operating force input to the select lever 2 is detected by the torque sensor 60 and input to the control unit 22. Further, the operation position of the select lever 2 at that time is detected by the potentiometer 61 as an angle change of the select lever 2 and is output to the control unit 22 as a stroke angle signal.
The operation position on the automatic transmission side is output to the control unit 22 as an angle signal by detecting the rotational position of the rotary shaft 64 connected to the control arm 20 via the control cable 18 with the potentiometer 65.

  The output value of the torque sensor 60 is first input to the drift correction block 70 of the control unit 22. In the drift correction block 70, the operation speed of the select lever 2 from the differentiator 74 and the range stop position information from the position / operation start / direction determination block 71 are obtained, and the select lever 2 is stopped at the range stop position. At this time, the zero point correction of the torque sensor 60 is performed, and the corrected operation force signal is output to the adder 73, the position / operation start / direction determination block 71, and the torque value diagnosis block 75.

  In the position / operation start / direction determination block 71, the current stroke angle of the select lever 2 is determined based on the stroke angle signal from the potentiometer 61. Further, the operation start, the operation direction, the operation speed, and the operation acceleration of the select lever 2 are determined from the stroke angle signal, the differential value of the stroke angle signal, and the operation force signal, and the determination results are used as the target reaction force table 72 and the drift correction block 70. To the main controller 221 and the torque value diagnosis block 75.

  The differentiator 74 differentiates the stroke angle signal from the potentiometer 61 to calculate the operation speed, and outputs the operation speed to the drift correction block 71, the position / operation start / direction determination block 71, and the torque value diagnosis block 75.

  In the torque value diagnosis block 75, when the select lever 2 is located at the P range position and is not operated, an inspection drive signal is output and current is supplied to the electric motor 62, and the select lever 2 is moved in the direction opposite to the R range direction. The torque sensor is pressed against the elastic portion 219, and the torque sensor is diagnosed with the generated torque value. If there is an abnormality, an abnormality signal is output to the failure diagnosis block 76 (however, only when IGN is ON).

  In the failure diagnosis block 76, it is determined whether or not the torque value at the time of test driving input from the torque value diagnosis block 75 is within a predetermined range. If abnormal, an abnormal stop signal is sent to the motor drive control block 77. And a failure warning signal is output.

  In the target reaction force table 72, a target for generating a sense of resistance corresponding to the stroke angle of the select lever 2 from the stroke angle signal and the operation direction of the select lever 2 obtained by the position / operation start / direction determination block 71. The reaction force is calculated and output to the adder 73.

  The adder 73 calculates the deviation between the operation force signal and the target reaction force, and outputs the calculation result to the main controller 221.

  The main controller 221 calculates a drive current value corresponding to the deviation between the operation force signal and the target reaction force, and outputs it to the motor drive control block 77.

  The motor drive control block 77 drives the current motor 63 to generate a sense of resistance based on the drive current value from the main controller 221.

The adder 78 calculates the deviation between the outputs of the potentiometer 61 and the potentiometer 65 and outputs the calculation result to the position FB controller 79.
Here, when calculating the deviation between the potentiometer 61 and the potentiometer 65, it is desirable to calculate the deviation in a state where the two potentiometers 61 and 65 correspond by multiplying by a coefficient.

  The position FB controller 79 calculates a drive current value corresponding to the operation speed from the position / operation start / direction discriminating block 71 and the deviation between the output angles of the two potentiometers 61 and 65, and outputs it to the motor drive control block 80. .

  The motor drive control block 80 drives the electric motor 63 based on the drive current value from the position FB controller 79.

Next, the operation will be described.
[Select control]
In the second embodiment, a resistance force due to the driving of the electric motor 62 is added to the detent force due to the engagement between the detent plate 81 and the detent pin 83 provided in the select lever 2 portion, and the select lever 2 can be sensed with moderate moderation. To be manipulated. The generation of the resistance force is performed under the control of the main controller 221 with reference to the target reaction force table 72.
The operation position of the select lever 2 is detected by a potentiometer 61, and the electric motor 63 is driven so as to perform feedback control so as to eliminate the deviation between the output values of the two potentiometers 61 and 65 so as not to be delayed. 19 control arms 20 are driven. Therefore, although not mechanically connected, the driver is made to realize that the range is switched by operating the select lever 2.
In the second embodiment, the detent structure of the automatic transmission 19 is the same as that of the first embodiment, but all the operations of the control arm 20 of the automatic transmission 19 are performed by driving the electric motor 63.

[Improvement of design freedom by electrical connection]
In the second embodiment, since the select lever side and the automatic transmission side are only electrically connected, the space saving of the select lever 2 and the degree of freedom in arrangement are increased.

[Necessity for diagnosis of torque sensor output value]
In the second embodiment, an appropriate operational resistance feeling is generated by applying torque to the select lever 2 by driving the electric motor 62. When an abnormality occurs in the output value of the torque sensor 60, if the driving force of the electric motor 62 becomes too small (the resistance feeling becomes too small), the select lever 2 can be operated lightly, and the driver It occurs that the select lever 2 is moved too much.
Further, if the driving force of the electric motor 62 becomes too large (resistance feeling becomes too great), the select lever 2 may become heavy.
In contrast, in the torque sensor failure diagnosis method of the second embodiment and the automatic transmission select assist device equipped with the torque sensor using this failure diagnosis method, a torque value diagnosis block 75 and a failure diagnosis block 76 are provided. ing.

[Flow of torque sensor failure diagnosis]
FIG. 14 is a flowchart showing a flow of a torque sensor failure diagnosis process executed by the control unit 22.
Steps S201, S202, and S204 to S209 are the same as those in the first embodiment, and a description thereof will be omitted.
In the second embodiment, in step S203, whether or not there is an operation is determined from the output value from the torque sensor.

[Torque sensor diagnosis]
The normal process is the same as that of the first embodiment, and thus the description thereof is omitted.
In the case of abnormality, in the second embodiment, the operation can be performed with a lighter force than usual by stopping the control. For this reason, the failure diagnosis block 76 outputs a failure alarm.
Therefore, the control of the electric motor 62 can be stopped to prevent further malfunction, and the vehicle can run in that state.
Since other operations are the same as those in the first embodiment, description thereof will be omitted.

Next, the effect will be described.
In the second embodiment, the following effects can be obtained in addition to the effects (1), (4) and (5) of the first embodiment.

  (3) A torque sensor 60 for detecting an input operation force to the select lever 2 to be interlocked with the control arm 20 of the automatic transmission 19, a potentiometer 61 for detecting the operation position of the select lever 2, and a range position of the control arm 20 A potentiometer 65 attached to the rotary shaft 64 for detection, a select lever side provided with an electric motor 62 which gives the select lever 2 an appropriate operating resistance and moderation, an electric motor 63 for switching the range position of the control arm 20, Based on the detected input operation force and operation position, a control command for changing the resistance force is output to the electric motor 62, and the range position is switched for the electric motor 63 based on the operation position and the range position. And a control means for outputting a control command for the automatic transmission to have a movable range end. Since the electric motor 62 is driven so as to press the select lever 2 against the fixed end 218 from the P range and the abnormality of the torque sensor 60 is diagnosed, changes in magnetic characteristics due to impact, overload, etc. Abnormality of the shaft 211 of the torque sensor 21, abnormalities of the coil such as a partial short of the excitation coil 212 and the detection coil 213 of the torque sensor 21, abnormalities of electronic components for torque detection due to erroneous attachment, secular change, overload, etc. Therefore, it is possible to determine whether or not the torque sensor 21 has any abnormality without adding another device, and the select lever 2 and the control arm 20 of the automatic transmission 19 are only electrically connected. The lever 2 can be reduced in size, and the degree of freedom in layout can be further increased.

  (7) When it is determined from the output value of the torque sensor 60 that the select lever 2 is stopped, an abnormality determination of the torque sensor 60 is performed. Therefore, an abnormality diagnosis is performed in this state, and the abnormality diagnosis returns to a normal operation. In addition to being able to prevent the influence, the abnormality diagnosis can be performed without being affected by the operation.

(Other embodiments)
The embodiment of the present invention has been described based on the first example. However, the specific configuration of the present invention is not limited to the first example, and the design does not depart from the gist of the invention. Any changes and the like are included in the present invention.
For example, in the first embodiment, the torque sensor 21 is used as the input operation force detection means for detecting the input operation force of the select lever 2. However, the input is based on the supply current value to the electric motor 15, the rotation speed of the electric motor 15, and the like. It is good also as a structure which estimates operation force.
In the first embodiment, the configuration in which the select lever 2 and the control arm 20 of the automatic transmission 19 are connected by the control cables 8 and 18 is shown. However, the operating force transmission means for transmitting the operating force of the select lever 2 to the control arm 20 is as follows. It is optional, and a configuration using a rod or linkage may be used.
The shape and size of the select lever 2 are arbitrary, and may be a switch shape that can be operated with a fingertip. In addition, the target operation reaction force characteristic is also changed to a characteristic that provides good operation characteristics according to the shape of the select lever 2.

The distribution ratio between the FF assist force Fff and the FB assist force Ffb with respect to the target assist force can be freely set according to the target operation characteristics.
In the first and second embodiments, the control is stopped when an abnormality is detected in the torque sensor, but a measure such as maintaining the range position at that time and fixing it to a predetermined range position or a predetermined gear ratio is performed. However, it is desirable that a safer measure is taken into account, such as retreat travel.
In the first embodiment, the FF control + FB control is used as the control of the main controller, but another control may be performed as shown in FIG.

It is a side view which shows the structure of the automatic transmission of 1st Example. It is a principal part perspective view which shows the detailed structure of an assist actuator. It is a control block diagram of a control unit. It is a perspective view which shows the structure of the detent of an automatic transmission. It is a flowchart which shows the flow of the assist control process of the select lever performed with a control unit. It is a characteristic view which shows the operation reaction force which generate | occur | produces in a select lever in a P-> R range direction. It is a characteristic view which shows the target operation reaction force of the select lever in the P → R range direction. It is a target assist force map in the P → R range direction. It is a flowchart which shows the flow of the process of a fault diagnosis of the torque sensor performed with a control unit. It is explanatory drawing of a torque sensor. It is explanatory drawing of an elastic part. It is a control block diagram of the control unit of the other example of 1st Example. It is a side view which shows the structure of the automatic transmission of 2nd Example. It is a control block diagram of the control unit of 2nd Example. It is explanatory drawing which shows the detent structure by the side of the select lever of the selection apparatus of the automatic transmission of 2nd Example. It is a flowchart which shows the flow of the process of a fault diagnosis of the torque sensor performed with the control unit of 2nd Example.

Explanation of symbols

1 select mechanism 2 select lever 3 center cluster 4 select knob 5 fulcrum shaft 7 select lever joint 8 control cable 9 assist actuator 10 input lever 11 input lever joint 12 output shaft 13 output lever 14 worm gear 15 electric motor 16 motor output shaft 17 output Lever joint 18 Control cable 19 Automatic transmission 20 Control arm 21 Torque sensor 22 Control unit 23 Wire harness 24 Contact 25 Potentiometer 26 Rotating shaft 27 Detent plate 27a Cam mountain 27b Valley 28 Spring plate 29 Detent pin 30 Parking pole 31 Cam shape Plate 32 Parking gear 33 Direction discrimination block 34 Target table block 35 Adder 36 FB Control unit 37 Multiplier 38 Adder 39 Multiplier 40 Integrator 41 Adder 42 FF control unit 43 FF compensation table block 44 Multiplier 45 Motor drive control block 50 Drift correction block 51 Differentiator 52 Torque value diagnosis block 53 Fault diagnosis block 211 (torque sensor) shaft 212 (torque sensor) excitation coil 213 (torque sensor) detection coil 214 rectifier 215 smoother 216 adder 217 amplifier 218 fixed end 219 elastic part 219a coil spring 219b receiving part 221 main controller 60 torque sensor 61 potentiometer 62 electric motor 63 electric motor 631 motor output shaft 64 rotary shaft 65 potentiometer 70 drift correction block 71 position / operation start / direction discrimination block 72 target reaction force table block Click 73 adder 74 differentiator 75 torque diagnostic block 76 failure diagnosis block 77 the motor driving control block 78 adder 79 position FB controller 80 the motor driving control block 81 the detent plate 81a cam lobes 81b valley 82 spring plate 83 detent pin

Claims (7)

In the torque sensor that detects the operating force input to the operating system,
A diagnostic motor for driving the operation system is provided;
Providing an elastic part close to the movable range end of the movable part of the operating system,
When the movable part of the operating system is at the end of the movable range,
Driving the diagnostic motor;
Pressing the movable part of the operating system against the elastic part to elastically deform the elastic part;
A torque sensor failure diagnosis method characterized by diagnosing an abnormality of the torque sensor based on whether or not the torque sensor outputs a predetermined torque by applying a reaction force to an operation system. In the torque sensor failure diagnosis method according to claim 1,
A torque sensor for detecting an input operation force to a select lever connected to the automatic transmission range position switching device;
An operation position detecting means for detecting an operation position of the select lever;
An assist motor that outputs an assist force to assist the driver's operating force to the select lever;
An assist force control means for outputting a control command for changing the assist force to the assist motor based on the detected input operation force and operation position;
In an automatic transmission select assist device having
A torque sensor characterized in that an abnormality of the torque sensor is diagnosed by driving an assist motor that also serves as a diagnostic motor so as to press the select lever from the P range to the elastic portion from the P range. Fault diagnosis method. In the torque sensor failure diagnosis method according to claim 1,
A torque sensor that detects an input operation force to a select lever that is interlocked without being connected to a range position switching device of an automatic transmission;
An operation position detecting means for detecting an operation position of the select lever;
Range position detection means for detecting the range position of the range position switching device;
Operation feeling generating means including a resistance generation motor that gives the select lever a suitable operation resistance and moderation,
A switching actuator for switching the range position of the range position switching device;
Based on the detected input operation force and operation position, a control command for changing the resistance force is output to the resistance-sensing motor, and the range position is switched for the switching actuator based on the operation position and the range position. Control means for outputting a control command to be
In the automatic transmission select device having
The end of the movable range is a P range, and a resistance generation motor that also serves as a diagnosis motor is driven so as to press a select lever from the P range to an elastic portion, thereby diagnosing an abnormality of the torque sensor. Torque sensor failure diagnosis method. In the torque sensor failure diagnosis method according to claim 2 or claim 3,
The operation position detecting means detects the amount of movement of the select lever at the time of abnormality diagnosis of the torque sensor,
Calculate the amount of deformation of the elastic part from the amount of movement,
A torque sensor failure diagnosis method characterized in that a torque to be detected by a torque sensor is calculated from a characteristic of elastic force with respect to a deformation amount of an elastic part. In the torque sensor failure diagnosis method according to claim 1,
An abnormality diagnosis method for a torque sensor, wherein abnormality diagnosis of the torque sensor is performed in a state where there is no input to an operation system. In the torque sensor failure diagnosis method according to claim 2,
Torque sensor failure diagnosis characterized in that an operation speed is detected from an operation position of the operation position detection means, and an abnormality diagnosis of the torque sensor is performed when it is determined from the operation speed that the select lever is stopped. Method. In the torque sensor failure diagnosis method according to claim 2,
6. A torque sensor failure diagnosis method according to claim 1, wherein when the selection lever is determined to be stopped from the output value of the torque sensor, an abnormality determination of the torque sensor is performed.

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