JP2005009570A - Select assist device for automatic transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a select assist device for an automatic transmission which can enhance a degree of freedom of the layout by downsizing a select lever and can obtain select lever operating force characteristics according to requirements, while securing reliability by mechanical coupling of a select lever and a range position switching device. <P>SOLUTION: The device is provided with a failure judging block 50 for executing self-diagnose of occurrence of failure from output differential values of a torque sensor 21 and a potentiometer 25. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention belongs to a technical field of a selection assist device for an automatic transmission that assists a driver's select lever operating force in a vehicle equipped with the automatic transmission.
[0002]
[Prior art]
Conventionally, a select lever of an automatic transmission is mechanically connected to a manual valve of the automatic transmission via an operating force transmission means such as a rod or a 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 1).
[0003]
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 2).
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 9-323559
[Patent Document 2]
Japanese Patent Laid-Open No. 2003-97694 [0006]
[Problems to be solved by the invention]
When the select lever is operated, a mechanical operating reaction force such as friction of the operating force transmission means, resistance of detent, etc. is generated, and thus 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.
[0007]
Therefore, the former of the above prior arts has a problem that the shape becomes large due to the length of the select lever, so that there are many restrictions on the installation place and the degree of freedom in layout in the vehicle interior is low.
[0008]
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.
[0009]
The present invention has been made paying attention to the above problems, and its object is to secure the reliability by mechanical connection of the select lever and the range position switching device, and to reduce the degree of freedom of layout by downsizing the select lever. It is an object of the present invention to provide a selection assist device for an automatic transmission that can achieve a widening range of the automatic transmission and obtain a select lever operating force characteristic according to demand.
[0010]
[Means for Solving the Problems]
In order to achieve the above-described object, in the automatic transmission select assist device according to claim 1 of the present invention, the input operation force for detecting the input operation force to the select lever connected to the range position switching device of the automatic transmission. Based on a detection means, an operation position detection means for detecting the operation position of the select lever, an assist actuator for outputting an assist force for assisting the operation force of the driver to the select lever, and the detected input operation force and operation position An assist force control means for outputting a control command for changing the assist force to the assist actuator, and a selection assist device for an automatic transmission, wherein the differential value of the output of the input operation force detection means and the operation position Failure determination means for self-diagnosing whether or not there is a failure from the differential value of the output of the detection means is provided.
[0011]
According to a second aspect of the present invention, in the select assist device for an automatic transmission according to the first aspect, in the failure determining means, a time lag between the output of the input operating force detecting means and the output of the operating position detecting means is detected. A timer for outputting time information is provided for consideration.
[0012]
According to a third aspect of the present invention, in the select assist device for an automatic transmission according to the second aspect, when the failure determination means determines that there is a failure, an assist control stop signal is output to the assist force control means. To do.
[0013]
【The invention's effect】
According to the first aspect of the present invention, while maintaining the mechanical connection between the select lever and the range position switching device, the lever operating force of the driver is assisted by the assist actuator, thereby ensuring reliability and reducing the size of the select lever. The expansion of the layout freedom by can be achieved together.
In addition, since there is provided a failure judgment means for self-diagnosis from the differential value of the output of the input operating force detection means and the differential value of the output of the operation position detection means, whether there is a change in the output value, It is possible to determine whether or not the output change has disappeared or become too small, and to perform self-diagnosis, and to promptly take measures and prevent further problems from occurring.
[0014]
According to the second aspect of the present invention, a comparison can be made in consideration of the time lag between the outputs of the input operation force detection means and the operation position detection means, and a more accurate determination can be made.
[0015]
According to the third aspect of the present invention, when the failure determination means determines that a failure has occurred, an assist control stop signal is output to the assist force control means to stop the assist control. In this way, it is possible to call attention to malfunctions, and to promote measures on the safe side.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment for realizing a select assist device for an automatic transmission according to the present invention will be described based on examples.
[0017]
(Example)
First, the configuration will be described.
FIG. 1 is a side view showing a configuration of an automatic transmission apparatus according to an embodiment, and FIG. 2 is a perspective view of a main part showing a detailed structure of an assist actuator.
[0018]
The automatic transmission apparatus according to the embodiment mainly includes 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 (assist force control means) 22. Yes.
[0019]
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.
[0020]
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.
[0021]
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 that meshes with a motor output shaft 16 of an electric motor 15 having a speed reduction mechanism.
[0022]
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.
[0023]
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.
[0024]
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.
[0025]
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.
[0026]
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.
[0027]
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.
[0028]
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.
[0029]
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.
[0030]
In the differentiator 51, the stroke angle signal from the potentiometer 25 is differentiated, the operation force signal from the torque sensor 21 is differentiated, and each differential value is output to the failure determination block 50.
[0031]
The timer 52 measures the elapsed time in response to a request from the failure determination block 50 and outputs it to the failure determination block 50.
[0032]
In the failure determination block 50, it is determined whether or not there is a failure from the differential value of the stroke angle signal from the differentiator 51 and the differential value of the operation force signal. Is output.
[0033]
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.
[0034]
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.
[0035]
The adder 35 calculates the deviation between the operation force signal and the target operation reaction force, and outputs the calculation result to the FB control unit 36.
[0036]
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.
[0037]
The FF control unit 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.
[0038]
The adder 41 outputs the output sum (feedback assist force + feed forward 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.
[0039]
A motor drive control block (corresponding to an assist force control unit) 45 drives the electric motor 15 based on the target assist force.
[0040]
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.
[0041]
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.
[0042]
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.
[0043]
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.
[0044]
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.
[0045]
In step S2, the stroke angle is read from the stroke angle signal of the potentiometer 25, and the process proceeds to step S3.
[0046]
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.
[0047]
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.
[0048]
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.
[0049]
In step S6, target table reading processing is performed, and the process proceeds to step S7.
[0050]
In step S7, the FF assist force is set from the read FF compensation table, and the process proceeds to step S8.
[0051]
In step S8, the FB assist force is set from the read target table, and the process proceeds to step S9.
[0052]
In step S9, the 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.
[0053]
In step S10, the output duty ratio of the electric motor 15 is controlled so as to achieve the target assist force.
[0054]
In step S11, a failure is determined. When it is determined that a failure has occurred, a process for stopping the control is performed and the present control is terminated.
[0055]
[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.
[0056]
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 perform range switching 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.
[0057]
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, and 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.
[0058]
[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 presetting a target operation reaction force Ft [N] that provides a good operation characteristic with a sense of moderation for the driver according to the stroke angle of the select lever 2.
[0059]
[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 according to the stroke angle of the select lever 2.
[0060]
[FF control + FB control]
In the embodiment, the assist force is a deviation between the feed forward assist force Fff [N] set so as to be an operation force that is about ½ of 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] set on the basis of this, it is possible to achieve both responsiveness and disturbance suppression performance at a high level in the assist control of a select lever with a steep and large torque deviation, which is excellent. Operation characteristics can be realized.
[0061]
[About sensor failure]
Here, sensor failure will be described.
When the torque sensor 21 or the potentiometer 25 breaks down in the assist control in the select assist device of the present embodiment, erroneous recognition of the operation position of the select lever 2 or erroneous recognition of the operational reaction force occurs, and the assist force is insufficient in the assist control. As a result, the operation becomes heavy, or the assist force is excessively supplied to cause a malfunction.
Therefore, in this embodiment, a failure determination block 50 is provided.
[0062]
[Flow of failure judgment and processing]
FIG. 9 is a flowchart showing a flow of failure determination / processing executed by the control unit 22.
[0063]
In step S101, the differential value is calculated by differentiating the input value from the potentiometer 25.
[0064]
In step S102, the differential value is calculated by differentiating the input value from the torque sensor 21.
[0065]
In step S103, it is determined whether the differential value of the potentiometer 25 or the differential value of the torque sensor 21 is greater than zero. If either is greater than zero, the process proceeds to step S104, and if both are zero, the process is performed. finish.
[0066]
In step S104, the timer is started and the elapsed time is measured.
[0067]
In step S105, it is determined whether the elapsed time in the timer 52 has passed a predetermined time. If the predetermined time has passed, the process proceeds to step S106. If the predetermined time has not passed, the process proceeds to step S105. .
[0068]
In step S106, it is determined whether the differential value of the potentiometer 25 is zero. If it is zero, the process proceeds to step S107, and if not, the process proceeds to step S109.
[0069]
In step S108, it is determined that the potentiometer 25 has failed, and an assist control stop signal is output to the motor drive control block 45.
[0070]
In step S109, it is determined whether the differential value of the torque sensor 21 is zero. If it is zero, the process proceeds to step S110, and if it is not zero, the process is terminated.
[0071]
In step S110, it is determined that the torque sensor 21 has failed, and an assist control stop signal is output to the motor drive control block 45.
[0072]
[Failure judgment and processing]
(1) In the case of normal operation If the operation of the select lever 2 is normally performed, the operation position detected by the potentiometer 25 and the operation reaction force detected by the torque sensor 21 should change. Therefore, if the timer is started with the detection of either the potentiometer 25 or the torque sensor 21 as a trigger and the response deviation is waited until the lapse of the fixed time counted in step S105, the differential value of the potentiometer 25 and the differential of the torque sensor 21 The value should be greater than zero. For this reason, the process proceeds from step S106 to step S109, and the normal assist control is maintained by completing the process.
[0073]
(2) Normal operation stop When the operation is normal and the operation is not performed, both the output value of the potentiometer 25 and the output value of the torque sensor 21 are not changed, so that the differential values are both zero. Become. This is determined to be normal and not operated in step S103, and the operation is terminated.
[0074]
(3) In the case of a potentiometer failure If a failure occurs in the potentiometer 25 and the stroke angle signal is not output, an operation is performed and the output value of the torque sensor 21 changes, and the differential value becomes greater than zero. As a trigger, the timer is started in the process of step S104. However, the differential value of the potentiometer 25 becomes zero when the output value does not change even after a certain time has elapsed. This is determined as a failure of the potentiometer 25 in the processing from step S106 to step S107, and the assist control stop signal is output to the motor drive control block 45 in the processing in step S108 to stop the assist control. In this state, since the assist force is not applied, the operation becomes heavy, but a safe state in which malfunction is prevented is obtained.
Further, the control is prevented from becoming unstable due to the failure of the potentiometer 25.
[0075]
(4) In the case of failure of the torque sensor When a failure occurs in the torque sensor 21 and the operation force signal is not output, the operation is performed, the output value of the potentiometer 25 changes, and the differential value becomes greater than zero. With this as a trigger, the timer is started in the process of step S104. However, the differential value of the torque sensor 21 becomes zero when there is no change in the output value. This is determined as a failure of the torque sensor 21 in the processing from step S106 to step S109, and the assist control stop signal is output to the motor drive control block 45 in the processing in step S110 to stop the assist control. In this state, since the assist force is not applied, the operation becomes heavy, but a safe state in which malfunction is prevented is obtained.
[0076]
Next, the effect will be described.
In the automatic transmission select assist device of the present embodiment, the following effects can be obtained.
[0077]
(1) 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 the 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.
[0078]
In addition, since a failure determination block 50 is provided for self-diagnosis whether there is a failure from the differential value of the output of the torque sensor 21 and the differential value of the output of the potentiometer 25, whether there is a change in the output value or not, the change in one output The self-diagnosis can be performed by determining whether or not it is lost or too small, and the countermeasures can be taken promptly to prevent further problems.
[0079]
(2) Since the failure determination block 50 is provided with the timer 52 for outputting time information so as to consider the time lag between the output of the torque sensor 21 and the output of the potentiometer 25, the time lag between the output of the torque sensor 21 and the potentiometer 25 is taken into account. And can make more accurate judgments.
[0080]
(3) If the failure determination block 50 determines that there is a failure, an assist control stop signal is output to the motor drive control block 45, so that even if there is a failure, the operation of the select lever 2 will not be uncomfortable, and a malfunction will be warned. Can be encouraged to deal with the safety side.
[0081]
(Other embodiments)
As described above, the embodiments of the present invention have been described based on the examples. However, the specific configuration of the present invention is not limited to the examples, and there are design changes and the like without departing from the scope of the invention. However, it is included in the present invention.
For example, in the 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, but the input operation force is determined from 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.
In the 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 operation force transmitting means for transmitting the operation force of the select lever 2 to the control arm 20 is arbitrary. There may be a configuration using a rod or a linkage.
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.
[0082]
The distribution ratio of 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 embodiment, it is assumed that the differential value zero is not zero in a strict sense and is equal to or less than a value at which it can be determined that the potentiometer 25 and the torque sensor 21 are not outputting normally.
In the embodiment, the assist control is stopped when it is determined that there is a failure. However, a warning notifying the driver of the failure may be further performed so that the failure is recognized and an operation to the safe side is further urged.
The differential value calculation of the potentiometer 25 and the differential value calculation of the torque sensor 21 according to the embodiment may be performed by using a trigger when one of the output values changes.
[Brief description of the drawings]
FIG. 1 is a side view showing a configuration of an automatic transmission according to an embodiment.
FIG. 2 is a main part perspective view showing a detailed structure of an assist actuator.
FIG. 3 is a control block diagram of a control unit.
FIG. 4 is a perspective view showing a detent structure of the automatic transmission.
FIG. 5 is a flowchart showing a flow of select lever assist control processing executed by the control unit;
FIG. 6 is a characteristic diagram showing an operation reaction force generated in the select lever in the P → R range direction.
FIG. 7 is a characteristic diagram showing a target operation reaction force of the select lever in the P → R range direction.
FIG. 8 is an FF assist force map in a P → R range direction.
FIG. 9 is a flowchart showing a flow of failure determination processing executed by the control unit.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Select mechanism part 2 Select lever 3 Center cluster 4 Select knob 5 Support 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 Contactor 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 the multiplier 40 integrator 41 adder 42 FF controller 43 FF compensation table block 44 the multiplier 45 a motor driving control block 50 malfunction decision block 51 differentiator 52 timer 221 main controller

Claims (3)

An input operation force detecting means for detecting an input operation force to the select lever connected to the range position switching device of the automatic transmission;
An operation position detecting means for detecting an operation position of the select lever;
An assist actuator that outputs an assist force to assist the operating force of the driver to the select lever;
An assist force control means for outputting a control command for changing the assist force to the assist actuator based on the detected input operation force and operation position;
A selection assist device for an automatic transmission having
A selection assist device for an automatic transmission, comprising: a failure judging means for self-diagnosis of whether or not there is a malfunction from a differential value of an output of the input operating force detection means and a differential value of an output of the operating position detection means. In the automatic transmission select assist device according to claim 1,
A selection assist device for an automatic transmission comprising a timer for outputting time information so as to take into account a time lag between the output of the input operation force detection means and the output of the operation position detection means in the failure determination means . In the automatic transmission select assist device according to claim 2,
A selection assist device for an automatic transmission, wherein the failure determination means outputs an assist control stop signal to the assist force control means when it is determined that there is a failure.

Images