JP2018040397A - Control device of automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device of an automatic transmission capable of suppressing increase of manufacturing costs while securing high reliability.SOLUTION: In a case when a shift position is kept in a P range, a hydraulic pressure of a hydraulic chamber 350a is discharged and a piston 351 is kept in a state of moving forward in a direction of an arrow E (first position). In this state, a lock claw member 372 is engaged with a groove portion 351b to keep a lock state. When the shift position is transferred to a range excluding the P(parking) range, a control unit commands supply of the hydraulic pressure to the hydraulic chamber 350a while keeping the engagement state of the lock claw member 372 with the groove portion 351a. The control unit determines failure of a locking mechanism portion including a parking lock solenoid 37 in an unlocked state, when the movement (moving backward) of the piston 351 to a direction opposite to the arrow E is detected within a prescribed time from the command of supplying the hydraulic pressure.SELECTED DRAWING: Figure 8

Description

  The present invention relates to an automatic transmission control device, and more particularly to a parking control technique in a shift-by-wire automatic transmission control device.

  The shift-by-wire automatic transmission employs a configuration in which a mechanical parking lock mechanism is provided to ensure a double system. Specifically, even when the oil pressure drops while traveling in the drive range, the state other than parking is maintained, and conversely, the oil pressure acts while stopping in the parking range. However, a lock mechanism is provided to prevent the parking state from being released.

  For the parking lock mechanism as described above, it is necessary to provide a configuration for detecting both a failure in the locked state and a failure in the unlocked (unlocked) state. A configuration for detecting such a failure of the parking lock mechanism is disclosed in Patent Document 1. In Patent Document 1, a first position sensor for detecting that the parking pole is engaged with the notch of the parking gear, and a second position for detecting the position of the lock member that locks the position of the parking pole. There is disclosed a technique for providing a failure sensor of a parking lock mechanism by providing two sensors, a position sensor.

JP 2007-303680 A

  However, the technique disclosed in Patent Document 1 has problems from the viewpoints of both manufacturing cost and reliability. That is, in the automatic transmission of a vehicle, it is continually required to reduce the manufacturing cost. However, in the technique disclosed in Patent Document 1, the manufacturing cost increases because two sensors are provided for detecting a failure of the parking lock mechanism. Resulting in.

  Moreover, in the technique disclosed in Patent Document 1, since two sensors are provided, the failure rate is increased.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a control device for an automatic transmission that can suppress an increase in manufacturing cost while ensuring high reliability. And

  An automatic transmission control device according to an aspect of the present invention is provided in a power transmission path between a drive source and wheels, and includes a power transmission shaft, a parking mechanism, an actuator, and a lock mechanism. The automatic transmission provided is a control target.

  The power transmission shaft is a shaft that transmits power to the wheels.

  When the shift position is in the parking range, the parking mechanism is in a restrained state that restricts the rotation of the power transmission shaft, and when the shift position is in a range other than the parking range, the parking mechanism rotates. It is a mechanism part which will be in the constraint release state which cancels restraint.

  The actuator has a piston movable between a first position and a second position, and the piston is connected to the parking mechanism. The actuator places the parking mechanism in the restrained state by setting the piston in the first position, and places the parking mechanism in the restrained release state by setting the piston in the second position.

  The lock mechanism is a mechanism that mechanically locks the position of the piston when the piston of the actuator is in the first position.

  The control device for an automatic transmission according to this aspect is a shift-by-wire control device, and includes a shift position determination unit, a parking lock command unit, an actuator drive command unit, and a parking lock failure determination unit.

  The shift position determination means is means for acquiring information related to the shift position and determining that the shift position has been shifted from the parking range to a range other than the parking range.

  The parking lock command means determines the position of the piston with respect to the lock mechanism when the shift position determination means determines that there has been a transition operation from the parking range to a range other than the parking range. A means for commanding to maintain the mechanically locked state at the first position.

  The actuator drive command means is configured to move the piston to the actuator in a state where the parking lock command means commands to maintain a state where the piston is mechanically locked at the first position. It is means for instructing driving from the first position to the second position.

  When the parking lock failure determination means determines that the position of the piston has deviated from the first position within a predetermined time after the actuator drive command means instructs to drive the piston, the lock mechanism section Is means for determining that a failure occurs in the unlocked state.

  In the automatic transmission control device according to this aspect, when the shift position is shifted from the parking range to a range other than the parking range (hereinafter, sometimes referred to as “N-parking range”), parking is performed. The lock command means commands the lock mechanism to drive the actuator after instructing the lock mechanism to maintain the piston position locked in the first state.

  When such control is performed, the piston of the actuator does not move when the lock mechanism is functioning normally. That is, the movement of the piston is prevented by the mechanical lock at the first position by the lock mechanism.

  On the other hand, when the lock mechanism part is malfunctioning in the unlocked (released) state, the piston of the actuator moves and moves from the first position after a predetermined time has elapsed. In this case, it is determined by the parking lock failure determination means that the lock mechanism unit has failed in the unlocked state (released state).

  As described above, in the control device for an automatic transmission according to this aspect, the lock mechanism portion is unlocked (released state) without providing a sensor for determining whether or not the lock mechanism portion is in the locked state. It is possible to detect a failure. Therefore, the number of sensors provided can be reduced as compared with the technique disclosed in Patent Document 1.

  Therefore, in the automatic transmission control device according to this aspect, an increase in manufacturing cost can be suppressed while ensuring high reliability.

  In the automatic transmission control device according to another aspect of the present invention, in the above configuration, the piston has a first surface and a second surface that face each other in the direction of movement, and the actuator includes the first The hydraulic actuator further includes a hydraulic chamber facing the surface, and a return spring that applies an elastic force to the second surface.

  And the said actuator drive command means of the control apparatus which concerns on this aspect instruct | indicates to supply hydraulic pressure with respect to the said hydraulic chamber, when moving the said piston from the said 1st position to the said 2nd position.

  In the control device for an automatic transmission according to this aspect, the piston of the actuator is moved from the first position to the second position by supplying hydraulic pressure to the hydraulic chamber. Conversely, the piston can be moved from the second position to the first position by discharging the hydraulic pressure in the hydraulic chamber.

  Therefore, when this mode is adopted, even if the hydraulic pressure cannot be supplied for some reason, the piston can be moved to the first position by the elastic force of the return spring. A parking state in which the rotation of the power transmission shaft is restricted is set.

  Therefore, the automatic transmission control device according to this aspect is superior in ensuring higher safety.

  The automatic transmission to be controlled by the control device according to another aspect of the present invention further includes a position detection unit that detects that the piston is in the first position.

  And the said parking lock failure determination means of the control apparatus of the automatic transmission which concerns on this aspect determines that the said piston remove | deviated from the said 1st position based on the position detection information of the said piston from the said position detection part.

  In the control device for an automatic transmission according to this aspect, the position of the piston (whether the parking mechanism is in a restrained state or the restraint released state) and the unlocking state of the lock mechanism are detected by one position detection unit. Two faults can be detected. Therefore, it is advantageous in securing high reliability while suppressing an increase in manufacturing cost.

  The control apparatus for an automatic transmission according to another aspect of the present invention further includes vehicle state determination means in the above configuration. The vehicle state determination means acquires information on whether or not the vehicle is in a stopped state, and can perform an unlock failure diagnosis when the vehicle is in a stopped state and the shift position is in a parking range. It is a means to determine.

  In the automatic transmission control device according to this aspect, when the vehicle lock determination unit determines that the unlock failure diagnosis is possible, the parking lock command unit When the position of the piston is instructed to be mechanically locked at the first position, the actuator drive command means determines that the parking state is determined when the vehicle state determination means determines that the unlock failure diagnosis is possible. The lock command means instructs the actuator to move the piston from the first position to the second position after instructing the piston to be mechanically locked at the first position. The parking lock failure determination means determines that the vehicle state determination means determines that the unlock failure diagnosis is possible. Thus, when it is determined that the position of the piston has moved from the first position within a predetermined time after the actuator drive command means commands to drive the piston, the lock mechanism is unlocked. Determine that there is a failure.

  In the control device for an automatic transmission according to this aspect, when the vehicle state determination unit determines that the unlock failure diagnosis is possible, the lock mechanism unit even if the shift position is not shifted from the parking range to the N-parking range. It can be checked whether or not the device is malfunctioning in the unlocked state.

  Therefore, the automatic transmission control apparatus according to this aspect can execute a failure check in the unlocked state of the lock mechanism portion at a high frequency, which is advantageous in ensuring higher reliability.

  In the automatic transmission control device according to another aspect of the present invention, in the above configuration, the actuator drive command unit moves the piston to the actuator after the determination by the parking lock failure determination means. Command to drive to position.

  In the control device for the automatic transmission according to this aspect, the vehicle state determination means instructs to drive the piston to the first position after performing a failure check when it is determined that the unlock failure diagnosis is possible. Control is returned when the position is in the parking range. Therefore, in the automatic transmission control device according to this aspect, it is possible to prevent the driver who drives the vehicle from feeling uncomfortable while performing a failure check of the lock mechanism portion at a high frequency.

  The control apparatus for an automatic transmission according to another aspect of the present invention, in the above-described configuration, issues a warning when the parking lock failure determination unit determines that the lock mechanism unit has failed in the unlocked state. Warning means for instructing to do so is further provided.

  In the automatic transmission control device according to this aspect, the warning means is provided, so that the driver can recognize the failure of the lock mechanism. Therefore, the automatic transmission control device according to this aspect can prompt the driver to respond promptly in the event of a failure of the lock mechanism.

  As specific warning means, for example, various means such as warning display on an information display, warning lamp lighting, warning sound or voice warning can be adopted. Further, the failure information may be directly transmitted to the server of the manufacturer or dealer by wireless or the like.

  In the control device for an automatic transmission according to each aspect described above, an increase in manufacturing cost can be suppressed while ensuring high reliability.

1 is a schematic diagram showing a partial configuration of a vehicle 1 according to a first embodiment of the present invention. 2 is a schematic perspective view showing a configuration of a parking mechanism portion and its periphery in the automatic transmission 3. FIG. It is a model front view which shows the parking lock cancellation | release state in a parking mechanism part. It is a model front view which shows the parking lock state in a parking mechanism part. 2 is a schematic block diagram illustrating a configuration related to a control system in a vehicle 1. FIG. 3 is a functional block diagram showing the configuration of a control unit 12 by function. FIG. 4 is a flowchart relating to a failure determination of a parking lock mechanism executed by a control unit 12; It is a schematic diagram which shows the state in which the parking actuator 35 is locked by the parking position. It is a schematic diagram which shows the state by which the parking actuator 35 was unlocked by the parking position. It is a schematic diagram which shows the state by which the parking actuator 35 is unlocked in positions other than a parking position. It is a schematic diagram which shows the state in which the parking actuator 35 is locked in positions other than a parking position. It is a functional block diagram which shows the structure of the control unit 19 with which the vehicle which concerns on 2nd Embodiment of this invention is equipped according to a function. 4 is a flowchart relating to a failure determination of a parking lock mechanism executed by a control unit 19;

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The form described below is one embodiment of the present invention, and the present invention is not limited to the following form except for the essential configuration.

[First Embodiment]
1. Configuration of Vehicle 1 The configuration of the vehicle 1 according to the present embodiment will be described with reference to FIG. FIG. 1 is a schematic diagram showing a partial configuration of the vehicle 1.

  As shown in FIG. 1, the vehicle 1 includes an engine 2, an automatic transmission 3, a differential gear 4, a drive shaft 5, and wheels 6.

  The engine 2 is provided as a drive source in the vehicle 1 and is an internal combustion engine that obtains power by burning fuel inside. Although the type of the engine 2 is not particularly limited, a four-cycle multi-cylinder gasoline engine is adopted as an example. The crankshaft of the engine 2 is connected to the automatic transmission 3.

  The automatic transmission 3 is a continuously variable transmission that transmits to the drive shaft 5 while decelerating the rotation of the crankshaft of the engine 2 or a planetary gear type automatic transmission. The vehicle 1 according to this embodiment is a so-called front engine / front drive type (FF type) vehicle, and the automatic transmission 3 has a configuration integrated with a differential gear 4 as a differential device. Power from the engine 2 is decelerated by the automatic transmission 3 and transmitted from the output shaft (not shown in FIG. 1) to the drive shaft 5 via the differential gear 4.

  The vehicle 1 includes an accelerator pedal 7, a brake pedal 8, a shift unit 9, a parking brake 10, an information display (warning output unit) 11, and a control unit 12.

  Although not shown in detail, the shift unit 9 is provided with a parking (P) range, a reverse (R) range, a neutral (N) range, a drive (D) range, and a manual (M) range. It has been. In this specification, the ranges other than the parking (P) range, such as the reverse (R) range, neutral (N) range, drive (D) range, manual (M) range, etc. N-parking range).

  The information display (warning output unit) 11 is a device for transmitting various types of information to the driver, and also displays a warning based on a command from the control unit 12.

  The control unit 12 executes control of the engine 2 and control of the automatic transmission 3 and displays various information including warnings on the information display 11. In the vehicle 1 according to this embodiment, the automatic transmission 3 is controlled by a shift-by-wire method.

2. Parking Mechanism Unit and its Surrounding Configuration in Automatic Transmission 3 The automatic transmission 3 is provided with a parking mechanism unit that is controlled by the control unit 12. This will be described with reference to FIGS.

  As shown in FIG. 2, the parking mechanism portion of the automatic transmission 3 includes a parking gear 31 and a parking pole 32.

The parking gear 31 has an annular shape, and the output shaft 30 is fitted into a hole inside thereof. The parking gear 31 is rotatable around the axis Ax ₃₀ as an integral part of the output shaft 30.

  A plurality of notches 31 a are formed in the outer peripheral portion of the parking gear 31 in the circumferential direction.

The parking pole 32 has a shaft (not shown) inserted through an insertion hole 32a formed in the base 32b. Then, the parking pawl 32 around the hole axis _{Ax 32} of the insertion hole 32a, the tip portion 32c is freely undulating.

  The parking pole 32 is provided with a protrusion 32d that protrudes toward the parking gear 31 at an intermediate portion between the base 32b and the tip 32c in the X direction. The protrusion 32 d is formed in a size that engages with the notch 31 a of the parking gear 31.

  For a parking mechanism having a parking gear 31 and a parking pole 32, a parking cam 33, a parking rod 34, a parking actuator 35, a parking position sensor 36, a parking lock solenoid (in FIGS. 2 to 4). , Not shown).

  The parking cam 33 has a cam surface that is in contact with the tip 32c of the parking pole 32. When the parking cam 33 moves in the Y direction, the tip end portion 32c of the parking pole 32 is configured to rise and fall.

  The parking rod 34 is a rod-shaped member that connects the parking cam 33 and the parking actuator 35. The parking rod 34 moves in the Y direction as indicated by an arrow A as the parking actuator 35 is driven.

  The parking actuator 35 pushes and pulls (forwards / retreats) the parking rod 34 by supplying and discharging hydraulic pressure to and from the hydraulic chamber.

  The parking position sensor 36 is a sensor for detecting the position of the piston of the parking actuator 35. Specifically, the piston of the parking actuator 35 can output different electrical signals as detection information at the first position and the second position, and sends the detection information to the control unit 12.

  Here, when the piston of the parking actuator 35 is at the most retracted position (second position) in the Y direction, the engagement between the notch 31a of the parking gear 31 and the protrusion 32d of the parking pole 32 is released. Thus, the output shaft 30 is in a state where its rotation is not restrained (restraint released state).

  Specifically, when the piston of the parking actuator 35 is at the most retracted position (second position) in the Y direction, the parking pole 32 is separated from the parking gear 31 as indicated by an arrow B in FIG. It becomes a state. As a result, the engagement between the notch 31a of the parking gear 31 and the protrusion 32d of the parking pole 32 is released. As a result, the rotation of the output shaft 30 is not restrained (restraint released state).

  On the other hand, when the piston of the parking actuator 35 is at the most advanced position (first position) in the Y direction, as shown in FIG. Pressed to the side. As a result, the notch 31a of the parking gear 31 and the protrusion 32d of the parking pole 32 are engaged. Thus, when the notch 31a of the parking gear 31 and the protrusion 32d of the parking pole 32 are engaged, the rotation of the output shaft 30 is constrained (constrained state).

  The parking position sensor 36 is turned ON when the piston of the parking actuator 35 is at the position (first position) that is most advanced in the Y direction, and sends the detection information to the control unit 12.

3. Configuration Related to Control System in Vehicle 1 The configuration related to the control system in vehicle 1 will be described with reference to FIG. FIG. 5 is a schematic block diagram illustrating a configuration related to a control system in the vehicle 1.

  In the vehicle 1, various information is sequentially input to the control unit 12 from a plurality of sensors. Specifically, as shown in FIG. 5, the vehicle 1 includes a vehicle speed sensor 13, an accelerator pedal sensor 14, a brake pedal sensor 15, a parking brake operation sensor 16, and a gradient angle sensor (G sensor) 17. A shift position sensor 18 and a parking position sensor 36 are provided, and detection information is sequentially input from the sensors 13 to 18 and 36 to the control unit 12.

  The vehicle speed sensor 13 is a sensor that detects the speed of the vehicle 1.

  The accelerator pedal sensor 14 is a sensor for detecting the amount of depression (accelerator opening) of the accelerator pedal 7 (see FIG. 1) by the driver.

  The brake pedal sensor 15 is a sensor for detecting the pressure (brake pressure) of the brake fluid when the brake pedal 8 (see FIG. 1) is depressed by the driver.

  The parking brake operation sensor 16 is a sensor for detecting the state of the parking brake 10 when the parking brake 10 (see FIG. 1) is operated by the driver.

  The gradient angle sensor (G sensor) 17 is a sensor for detecting whether or not the vehicle 1 is tilted in the front-rear direction.

  The shift position sensor 18 includes a parking (P) range, a reverse (R) range, a neutral (N) range, a drive (D) range, and a manual (M) in the shift unit 9 (see FIG. 1). This is a sensor for detecting which range is selected.

  The parking position sensor 36 is as described above.

  The control unit 12 executes various calculations based on the input information from the sensors 13 to 18 and 36, and sequentially outputs control commands to the engine 2, the automatic transmission 3, and the warning output unit 11. To do. Of these, the control command for the engine 2 is actually made to the throttle valve, variable valve mechanism, spark plug, and fuel injection valve connected to the engine 2.

  The automatic transmission 3 includes the parking actuator 35 and the parking lock solenoid 37 described above, and the control unit 12 executes these controls.

  The control unit 12 outputs various warning information to the information display (warning output unit) 11 to display the warning.

4). Functional Configuration of Control Unit 12 The functional configuration of the control unit 12 will be described with reference to FIG. FIG. 6 is a functional block diagram showing the configuration of the control unit 12 by function.

  As shown in FIG. 6, the control unit 12 includes a shift position determination unit 120, a parking position determination unit 121, a parking actuator drive command unit 122, a parking lock solenoid drive command unit 123, A failure determination unit 124 and a warning output command unit 125 are included.

The shift position determination unit 120 sequentially acquires shift position information Inf ₁₈ from the shift position sensor 18 (see FIG. 5), and includes a parking (P) range, a reverse (R) range, and a neutral (N) range. The drive (D) range and the manual (M) range are selected.

The parking position determination unit 121 sequentially acquires parking position information Inf ₃₆ from the parking position sensor 36 (see FIG. 2), and the position of the piston in the parking actuator 35 (see FIG. 2) is determined as the parking position (first position). Position) or parking release position (second position).

  The parking actuator drive command unit 122 issues a drive command to the parking actuator 35. The parking lock solenoid drive command unit 123 issues a drive command to a parking lock solenoid 37, which will be described later with a specific configuration.

  Based on the determination result at the shift position determination unit 120 and the determination result at the parking position determination unit 121, the parking lock failure determination unit 124 detects that the parking lock mechanism unit including the parking lock solenoid 37 has failed in the unlocked state. It is determined whether or not.

  The warning output command unit 125 is configured to display an information display (warning output) when the parking lock failure determination unit 124 determines that the parking lock mechanism unit including the parking lock solenoid 37 has failed in the unlocked state (released state). Part) 11 is caused to display information on the failure.

5. The failure determination method of the parking lock mechanism part by the control unit 12 The failure determination method of the parking lock mechanism part performed by the control unit 12 will be described with reference to FIGS. FIG. 7 is a flowchart relating to the failure determination of the parking lock mechanism portion executed by the control unit 12, and FIGS. 8 to 11 show the state of the parking actuator 35 and the state of the parking lock mechanism portion in each situation. It is a schematic diagram.

  First, an example described below with reference to FIG. 7 is a failure determination method when the shift position is shifted from the parking range to the N-parking range. The state of the parking actuator 35 and the parking lock solenoid 37 when the shift position is in the parking range will be described with reference to FIG.

  As shown in FIG. 8, when the parking range is selected, the piston 351 of the parking actuator 35 is in the advanced (protruded) position (first position) as indicated by the arrow E. When the piston 351 is in the first position as described above, the protrusion 32d of the parking pole 32 is engaged with the notch 31a of the parking gear 31 as described with reference to FIG. (Restrained state).

  In addition, as shown in FIG. 8, when the parking range is selected, the plunger 371 of the parking lock solenoid 37 is retracted to the position indicated by the arrow D in order to secure the double system, thereby locking the parking range. The tip portion of the claw member 372 is engaged with a groove portion 351 b provided in the piston 351.

  As shown in FIG. 7, the control unit 12 first acquires various sensor information sequentially (step S1). The information to be acquired is as described with reference to FIG. When the operation for shifting from the parking range to the N-parking range is performed (step S2: Yes), the control unit 12 maintains the locked state of the parking lock mechanism with respect to the parking lock solenoid 37. Command (step S3). That is, as shown in FIG. 8, the state where the distal end portion of the lock claw member 372 is engaged with the groove portion 351b of the piston 351 is maintained.

  Returning to FIG. 7, the parking actuator 35 is instructed to supply hydraulic pressure in a state where the parking lock mechanism is locked (step S4). Specifically, as shown in FIG. 8, hydraulic pressure is supplied to the hydraulic chamber 350 a in the cylinder tube 350 via the port 350 b and the hydraulic pipe 38.

  Then, after instructing the supply of hydraulic pressure, the time is started using a timer or the like provided in the control unit 12 (step S5). This is because it takes a predetermined time for the hydraulic pressure in the hydraulic chamber 350a to rise to a predetermined value or more after the supply of the hydraulic pressure is commanded (step S4).

  Next, the control unit 12 determines whether or not the position of the piston 351 of the parking actuator 35 has retreated to the N-parking position (second position) based on the information from the parking position sensor 36, in other words, the piston 351. It is determined whether or not the position has deviated from the parking position (first position) shown in FIG. 8 (step S6). This determination (step S6) is continued until a predetermined time elapses from the start of timing in step S5 (step S8: No).

  Here, when the parking lock mechanism is functioning normally, the piston 351 moves because the tip of the lock claw member 372 is engaged with the groove 351b of the piston 351 as shown in FIG. Never do.

  However, when the parking lock mechanism is stopped in an unlocked state (released state) for some reason, that is, when the distal end portion of the lock claw member 372 and the groove portion 351b of the piston 351 are disengaged (for example, 9), the surface of the piston 351 on the hydraulic chamber 350a side (first surface) receives pressure from the hydraulic pressure and moves to the N-parking position (second position) (step S6). : Yes).

  As described above, when it is determined that the piston 351 has moved to the N-parking position (second position) (step S6: Yes), the control unit 12 indicates that the parking lock mechanism is unlocked (release failure). Is determined "(step S7), and the time measurement is terminated (step S9). Then, the control unit 12 causes the information display (warning output unit) 11 to output a failure warning (step S10). Note that the failure warning of the information display (warning output unit) 11 is maintained regardless of whether the ignition switch is on or off, and is canceled after inspection and repairs are performed at the maintenance shop. It is possible.

  On the other hand, when the predetermined time has elapsed with the determination of step S6 being “No” (step S8: Yes), the control unit 12 determines that “the parking lock mechanism is functioning normally” ( Step S11), the time measurement is finished (Step S12).

  Next, the control unit 12 instructs the parking lock solenoid 37 to switch the parking lock mechanism to the released state (step S13). The parking lock solenoid 37 that has received the command advances the plunger 371 as shown by the arrow F as shown in FIG. As a result, the lock claw member 372 also moves to the side indicated by the arrow F, and the engagement between the tip portion and the groove portion 351b of the piston 351 is released.

  Then, the control unit 12 issues a command in step 13 and then starts counting with a timer (step S14).

  Returning to FIG. 7, the control unit 12 determines whether or not the position of the piston 351 of the parking actuator 35 has moved to the N-parking position (second position) based on information from the parking position sensor 36 ( Step S15). This determination (step S15) is also continued until a predetermined time has elapsed from the start of time measurement in step S14 (step S17: No).

  When the position of the piston 351 of the parking actuator 35 moves to the N-parking position (second position) (step S15: Yes), the control unit 12 locks the parking lock mechanism with respect to the parking lock solenoid 37. Is commanded (step S16). That is, as shown in FIG. 9, when the engagement between the distal end portion of the lock claw member 372 and the groove portion 351b of the piston 351 is released and the hydraulic pressure is supplied to the hydraulic chamber 350a, the hydraulic chamber 350a side of the piston 351 As shown in FIG. 10, the pressing force on the surface (first surface) exceeds the elastic force of the return spring 352 on the other surface (second surface) of the piston 351, so that the piston 351 is indicated by an arrow G. Move to.

  When the piston 351 has finished moving as shown in FIG. 10, the control unit 12 issues a command to the parking lock solenoid 37. The parking lock solenoid 37 that has received the command causes the plunger 371 to move as shown in FIG. Retract as shown by arrow H. Thereby, the lock claw member 372 also moves to the side indicated by the arrow H, and the tip portion and the groove 351a of the piston 351 are engaged.

  When the predetermined time has elapsed with the determination in step S15 being “No” (step S17: Yes), the control unit 12 indicates that “a failure has occurred in a location other than the parking lock mechanism”. Determination is made (step S19), and the time measurement is terminated (step S20). That is, when the predetermined time has elapsed with the determination of step S15 being “No” (step S17: Yes), as shown in FIG. 9, the tip of the locking claw member 372 and the groove 351b of the piston 351 are Although the engagement is released and the parking actuator 35 is commanded to supply hydraulic pressure to the hydraulic chamber 350a, it means that the piston 351 does not change to the moved state as shown in FIG. .

  As a case where the control unit 12 makes the above determination in step S19, for example, a failure of the hydraulic pipe 38 and the hydraulic pump connected thereto, or a failure of the parking actuator 35 can be considered.

  Returning to FIG. 7, when the control unit 12 makes a determination as in step S <b> 19, the control unit 12 instructs the parking lock solenoid 37 to switch the parking lock mechanism to the locked state (step S <b> 21). Thereby, as shown in FIG. 8, the front end portion of the lock claw member 372 returns to the state of being engaged with the groove portion 351 b of the piston 351.

  Returning to FIG. 7, the control unit 12 instructs the information display (warning output unit) 11 after the instruction in step S <b> 21 that “a failure has occurred at a location other than the parking lock mechanism unit”. Is output (step S10).

  In the same way as above, for this failure warning as well, the warning is maintained regardless of whether the ignition switch is ON or OFF, and after the inspection / repair is performed at the maintenance shop. It can be released.

6). Effect In this embodiment, the parking position attached to the parking actuator 35 without providing a sensor for detecting whether the parking lock solenoid 37 and its associated part are locked or unlocked. Using the sensor 36, it is possible to detect a failure in the unlocked state of the parking lock solenoid 37 and its associated part. Therefore, the number of sensors provided can be reduced as compared with the technique disclosed in Patent Document 1.

  Therefore, in the present embodiment, by adopting the control unit 12 that performs the above-described failure determination, it is possible to suppress an increase in manufacturing cost while ensuring high reliability.

  Further, in the present embodiment, by supplying hydraulic pressure to the hydraulic chamber 350a of the parking actuator 35, the piston 351 moves to the position shown in FIG. 10 and the restriction of the output shaft 30 in the automatic transmission 3 is released. N-parking position (second position). Conversely, if the hydraulic pressure cannot be supplied for some reason, the piston 351 is held at the parking position (first position) by the elastic force of the return spring 352. Therefore, in the configuration of the present embodiment, even if the hydraulic pressure cannot be supplied for some reason, the piston 351 is moved to the parking position (first position shown in FIG. 9), and the output shaft 30 of the automatic transmission 3 is moved. It is possible to maintain a state in which the rotation of the motor is restricted.

  Therefore, this embodiment is advantageous in ensuring higher safety.

[Second Embodiment]
A second embodiment of the present invention will be described with reference to FIGS.
1. Configuration of Control Unit 19 First, the configuration of the control unit 19 that is different from the vehicle 1 according to the first embodiment in the configuration of the vehicle according to the present embodiment will be described with reference to FIG. FIG. 12 is a functional block diagram showing the configuration of the control unit 19 by function. In FIG. 12, the same functional parts as those of the control unit 12 of the first embodiment are denoted by the same reference numerals, and repeated description thereof is omitted.

  As shown in FIG. 12, the vehicle control unit 19 according to the present embodiment includes a vehicle state determination unit 196 in addition to the functional units included in the control unit 12 of the vehicle 1 according to the first embodiment.

The vehicle state determination unit 196 includes information on the vehicle speed from the vehicle speed sensor 13, information on the accelerator opening from the accelerator pedal sensor 14, information on the brake pressure from the brake pedal sensor 15, and the parking brake 10 from the parking brake operation sensor 16. Various information Inf _etc such as information on the state and information on the inclination of the vehicle from the gradient angle sensor (G sensor) 17 is sequentially input.

  The vehicle state determination unit 196 in the control unit 19 determines whether it is possible to diagnose that the parking mechanism unit in the automatic transmission 3 is malfunctioning in the unlocked state even when the shift position is in the N-parking range. It is a functional part to do.

  As shown in FIG. 12, the control unit 19 has the same configuration as that of the control unit 12 of the vehicle 1 according to the first embodiment except that the control unit 19 further includes a vehicle state determination unit 196. The same effect as the embodiment can be obtained.

2. The failure determination method of the parking lock mechanism part by the control unit 19 The failure determination method of the parking lock mechanism part executed by the control unit 19 when the shift position is in the parking range will be described with reference to FIG.

  First, an example described below with reference to FIG. 13 is a failure determination method in a state where the shift position is maintained in the parking range state.

  As shown in FIG. 13, the control unit 19 sequentially acquires the various information as described above (step S31). Next, the control unit 19 determines whether or not it is possible to determine whether or not the parking lock mechanism unit is malfunctioning in the unlocked state (step S32).

  Specifically, the vehicle is stopped, the accelerator 7 is not stepped on, the brake pedal 8 is stepped on or the parking brake 10 is pulled, and the slope angle is less than a predetermined angle. If satisfied, the control unit 19 determines that the parking lock mechanism is in a state where it can be determined whether or not it is malfunctioning in the unlocked state (step S32: Yes).

  Note that the conditions that the control unit 19 takes into consideration in the determination in step S32 need not necessarily be all of the above conditions. In short, any conditions may be used as long as safety is ensured when determining whether or not the parking lock mechanism is malfunctioning in the unlocked state.

  Subsequently, as shown in FIG. 13, when the control unit 19 determines that the parking lock mechanism is in a state where it can be determined whether or not it is malfunctioning in the unlocked state (step S32: Yes). The parking lock solenoid 37 is instructed to maintain the locked state of the parking lock mechanism (step S33). That is, as described above, as shown in FIG. 8, the state where the tip end portion of the lock claw member 372 is engaged with the groove portion 351b of the piston 351 is maintained.

  Then, the control unit 19 causes the parking actuator 35 to supply hydraulic pressure to the hydraulic chamber 350a (step S34), and starts counting with a timer (step S35). At this time, as shown in FIG. 8, when the parking lock mechanism is functioning normally, the tip of the lock claw member 372 is engaged with the groove 351b of the piston 351, so that the piston 351 moves. There is nothing to do (step S36: No). In addition, the determination in the said step S36 is continued until predetermined time passes (step S38: No). The reason is the same as above.

  When the control unit 19 determines in step S36 that the piston 351 has moved to the N-parking position (second position) (step S36: Yes), “the parking lock mechanism is unlocked (release failure). Is determined "(step S37), and the time measurement by the timer is terminated (step S39).

  Then, as in the first embodiment, the control unit 19 displays a warning on the information display (warning output unit) 11 that “the parking lock mechanism unit has an unlock failure (release failure)”. Is commanded (step S40).

  Finally, the control unit 19 discharges the hydraulic pressure from the hydraulic chamber 350a of the parking actuator 35 (step S41), and ends the failure determination of the parking lock mechanism.

  In this embodiment as well, once the failure warning is displayed, the warning is maintained regardless of whether the ignition switch is turned ON / OFF. After the inspection / repair is performed at the maintenance shop, It can be released.

  On the other hand, the control unit 19 determines that “the parking lock mechanism portion is functioning normally” when the predetermined time has elapsed with the determination in step S36 being “No” (step S38: Yes) ( Step S42), the time measurement is finished (Step S43). Then, the control unit 19 discharges the hydraulic pressure from the hydraulic chamber 350a of the parking actuator 35 (step S41), and ends the failure determination of the parking lock mechanism.

3. Effect As described above, in the present embodiment, even when the shift position remains in the parking range, it is possible to execute the unlock failure determination of the parking lock mechanism if the conditions such as the vehicle stop are satisfied. Yes. For this reason, in this embodiment, in addition to the effect which the said 1st Embodiment has, the failure check in the unlocking state of a lock mechanism part can be performed with high frequency, and it is superior in ensuring higher reliability. It is.

  Note that the unlock failure determination of the parking lock mechanism in the present embodiment may be performed at all timings that satisfy the above conditions, or may be performed after a certain period. In the case of performing a certain period of time, the control unit 19 is provided with a so-called calendar timer, and a determination can be made for each period scheduled in advance.

[Modification]
In the first embodiment and the second embodiment, the FF vehicle (front engine / front drive vehicle) equipped with the gasoline engine (engine 2) is adopted as an example of the vehicle. However, the present invention is not limited to this. It is not something to receive. As the engine, for example, a diesel engine or the like can be employed. Further, the present invention can be applied to a hybrid electric vehicle including an engine and an assist motor as a power source.

  In addition, vehicle types include FR vehicles (front engine / front drive vehicles), RR vehicles (rear engines / rear drive vehicles), MR vehicles (midship engines / rear drive vehicles), 4WD vehicles (four-wheel drive vehicles), etc. In addition, the present invention can be applied.

  In the first embodiment and the second embodiment, the structure of the automatic transmission 3 is not particularly described in detail. For example, a torque converter type automatic transmission can be employed, Semi-automatic transmissions and double clutch transmissions can also be used.

  In the first embodiment and the second embodiment, the parking gear 31 and the parking pole 32 are engaged and released via the parking cam 33. However, the present invention is not limited to this. Not receive. For example, the end of the piston 351 of the parking actuator 35 and the tip 32c of the parking pole 32 may be connected, and the parking pole 32 may be raised and lowered directly by the forward and backward movement of the piston 351.

  In the second embodiment, the control unit 19 performs the failure determination even when the shift position remains in the parking range based on the acquired information as shown in FIG. In addition to this, various conditions can be added. For example, in a configuration equipped with a function that can detect the distance between the vehicle and the front vehicle using a camera, a radar, or the like, it is possible to add a condition that the distance between the vehicle and the vehicle is a predetermined distance or more. Thereby, higher safety can be secured.

  Further, the ON / OFF state of the air conditioner switch and the outside air temperature may be taken into consideration as the availability condition for the release failure diagnosis in the second embodiment. Even if the parking range remains unchanged, the engine speed may increase when the air conditioner is switched on when the outside air temperature is high. In such a case, in consideration of safety, it is possible to satisfy the conditions for enabling the open failure diagnosis (step S32 in FIG. 13: No).

  In the first embodiment and the second embodiment, the parking actuator 35 is a hydraulic actuator that drives the piston 351 by supplying / discharging the hydraulic pressure. However, the present invention is limited to this. It is not a thing. For example, an electric actuator or a pneumatic actuator can be employed. Further, the actuator is not limited to the direct acting type, and a rotary type actuator can also be adopted.

1 Vehicle 3 Automatic Transmission 9 Shift Unit 11 Information Display (Warning Output Unit)
12, 19 Control unit (control device)
31 Parking Gear 32 Parking Pole 33 Parking Cam 35 Parking Actuator 36 Parking Position Sensor 37 Parking Lock Solenoid 124 Parking Lock Failure Determination Unit

Claims (6)

In the automatic transmission control device,
The automatic transmission is provided in a power transmission path between a drive source and wheels,
A power transmission shaft for transmitting power to the wheels;
When the shift position is in the parking range, the rotation state of the power transmission shaft is constrained. When the shift position is in a range other than the parking range, the rotation of the power transmission shaft is released. A parking mechanism that is in a state;
A piston that is movable between a first position and a second position; the piston is connected to the parking mechanism; and the parking mechanism is configured by setting the piston to the first position. An actuator that is in the restrained state and places the parking mechanism in the restrained release state by setting the piston in the second position;
A locking mechanism that mechanically locks the position of the piston when the piston of the actuator is in the first position;
With
The control device is a shift-by-wire control device,
Shift position determination means for acquiring information related to the shift position, and determining that the shift position has been shifted from the parking range to a range other than the parking range;
When the shift position determination means determines that there has been an operation of shifting from the parking range to a range other than the parking range, the position of the piston is mechanically moved at the first position with respect to the lock mechanism unit. Parking lock command means for commanding to maintain the locked state;
The parking lock command means commands the actuator to maintain the piston locked from the first position to the second position in a state in which the piston is mechanically locked at the first position. Actuator drive command means for commanding to drive to,
If it is determined that the position of the piston has deviated from the first position within a predetermined time after the actuator drive command means instructs to drive the piston, the lock mechanism unit has failed in the unlocked state. Parking lock failure determination means for determining that there is,
Comprising
Control device for automatic transmission. A control device for an automatic transmission according to claim 1,
The piston has a first surface and a second surface facing away from each other in the direction of movement;
The actuator is a hydraulic actuator further comprising a hydraulic chamber facing the first surface, and a return spring for applying an elastic force to the second surface,
The actuator drive command means commands the hydraulic chamber to supply hydraulic pressure when moving the piston from the first position to the second position;
Control device for automatic transmission. A control device for an automatic transmission according to claim 1 or 2,
The automatic transmission further includes a position detection unit that detects that the piston is in the first position,
The parking lock failure determination means determines that the piston is out of the first position based on the position detection information of the piston from the position detection unit.
Control device for automatic transmission. A control device for an automatic transmission according to any one of claims 1 to 3,
Vehicle state determination means for acquiring information on whether or not the vehicle is in a stopped state, and determining that an unlock failure diagnosis is possible when the vehicle is in a stopped state and the shift position is in a parking range. Further,
The parking lock command means mechanically locks the position of the piston at the first position with respect to the lock mechanism when the vehicle state determination means determines that the unlock failure diagnosis is possible. Command to state,
The actuator drive command means is a state in which the parking lock command means mechanically locks the position of the piston at the first position when the vehicle state determination means determines that the unlock failure diagnosis is possible. Instructing the actuator to move the piston from the first position to the second position;
The parking lock failure determination means is a case where the vehicle state determination means determines that the unlock failure diagnosis is possible, and within a predetermined time after the actuator drive command means instructs to drive the piston. , When it is determined that the position of the piston has deviated from the first position, it is determined that the lock mechanism portion is malfunctioning in the unlocked state.
Control device for automatic transmission. A control device for an automatic transmission according to claim 4,
The actuator drive command unit commands the actuator to drive the piston to the first position after the determination by the parking lock failure determination means.
Control device for automatic transmission. A control device for an automatic transmission according to any one of claims 1 to 5,
The parking lock failure determination means further comprises warning means for instructing to issue a warning when it is determined that the lock mechanism section has failed in the unlocked state.
Control device for automatic transmission.

Images