JP4376576B2 - Shift range switching device for automatic transmission - Google Patents

Description

  The present invention relates to a shift range switching device for an automatic transmission that switches a shift range of an automatic transmission via an actuator such as a motor, and more particularly to a shift actuator for an automatic transmission that can accurately grasp the reference position of the shift range. Related to control.

  2. Description of the Related Art Conventionally, in a shift range switching device that switches the shift range of an automatic transmission by electric control in accordance with the operation of a shift lever by a driver, one having an electric motor (for example, a DC motor) as a power source for shift range switching is known. ing.

  According to such a shift range switching device, the shift lever and the shift range switching mechanism are mechanically connected like a general switching device that directly switches the shift range of the automatic transmission by the operating force of the shift lever by the driver. Since there is no need to connect, there is no restriction on the layout when these parts are mounted on a vehicle, and the degree of freedom in design can be increased. Further, there is an advantage that the assembling work to the vehicle can be easily performed.

  Japanese Patent Laying-Open No. 2002-310294 (Patent Document 1) discloses a shift range switching device for an automatic transmission that allows easy assembly of an actuator and switches the shift range accurately. This shift range switching device includes a shift range switching mechanism for switching the shift range of an automatic transmission to various travel ranges including parking, an actuator that is a power source of the shift range switching mechanism, and a switch that is input by an external operation. A control circuit that controls the shift range of the automatic transmission to a shift range corresponding to the switching command by driving the actuator according to the command, and a detection that detects the shift range position of the automatic transmission and sends a detection signal to the control circuit A shift range switching device for an automatic transmission including a circuit. The control circuit sets a reference value for the shift range position of the automatic transmission from the detection signal of the detection circuit, and controls the actuator based on the reference value.

  According to the shift range switching device for an automatic transmission disclosed in Patent Document 1, the shift range of the automatic transmission is controlled to a shift range corresponding to the switching command by driving an actuator in accordance with a switching command input by an external operation. To do. Then, a reference value for the shift range position of the automatic transmission is set from the detection signal of the detection circuit for detecting the shift range position of the automatic transmission, and the actuator is controlled based on this reference value. For this reason, regardless of the assembly position accuracy of the shift range switching mechanism and the variation of each actuator, the step of adjusting the assembly angle when the actuator is assembled to the automatic transmission becomes unnecessary, and the actuator can be assembled to the automatic transmission. It becomes easy. Therefore, the assembly and maintenance of the actuator can be facilitated, and the shift range switching mechanism can be driven to accurately switch the shift range of the automatic transmission.

  On the other hand, as such a shift range switching device, in order to grasp the absolute position of the actuator when the power is cut off and re-introduced, the rotational position of the actuator and the shift range of the automatic transmission are nonvolatile before the power is cut off. Shift range switching devices that are stored in a volatile memory have been proposed.

  Japanese Patent Application Laid-Open No. 2002-323127 (Patent Document 2) discloses a shift range switching device for an automatic transmission that grasps the absolute position of an actuator and switches the shift range, has high durability reliability, and reduces manufacturing costs. This shift range switching device includes a shift range switching mechanism for switching the shift range of an automatic transmission to various travel ranges including parking, an actuator that is a power source of the shift range switching mechanism, and a switch that is input by an external operation. A control circuit that controls the shift range of the automatic transmission to a shift range corresponding to the switching command by driving the actuator according to the command, a power source that supplies power to the control circuit, the rotational position of the actuator, and the shift of the automatic transmission A shift range switching device for an automatic transmission including a nonvolatile rewritable memory for storing a range position. When the electric power supplied from the power source is cut off and reintroduced, the control circuit reads the rotational position of the actuator and the shift range position of the automatic transmission stored in the memory and sets them as initial values.

According to the shift range switching device for an automatic transmission disclosed in Patent Document 2, the shift range of the automatic transmission is controlled to a shift range corresponding to the switching command by driving an actuator in accordance with a switching command input by an external operation. To do. The rotational position of the actuator and the shift range position of the automatic transmission are stored in a non-volatile rewritable memory, and when the power supplied from the power source to the control circuit is cut off and reintroduced, the actuator stored in the memory The rotation position and the shift range position of the automatic transmission can be read out and set as initial values.
JP 2002-310294 A JP 2002-323127 A

  However, in the shift range switching device for an automatic transmission disclosed in Patent Document 1 described above, a detection circuit that detects the shift range position of the automatic transmission even if the effect of facilitating the assembly and maintenance of the actuator is exhibited. It is necessary to calculate the count value indicating the center of each range by referring to the count value of the counter from the output signal of the (neutral start switch). By setting the count value indicating each range as a reference value and controlling the actuator based on this reference value, the assembly angle when assembling the actuator to the automatic transmission can be adjusted regardless of variations in individual actuators. A neutral start switch is indispensable because it eliminates the need to perform the process and facilitates the assembly of the actuator to the automatic transmission. For this reason, there exists a problem of a weight increase and cost increase by a neutral start switch.

  Further, in the shift range switching device for an automatic transmission disclosed in Patent Document 2 described above, it is assumed that the absolute position of the rotation of the actuator is grasped. When only the relative change amount of the position can be detected, the actuator cannot be controlled appropriately, and a load is applied to the shift switching mechanism due to the rotation operation of the actuator, and the durability of the shift switching mechanism is reduced. On the other hand, if the shift switching mechanism is designed so as to improve the durability, the scale of the shift switching mechanism is increased and the cost is increased.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a shift range switching device that eliminates the need for a neutral start switch and further reduces the load on the shift switching mechanism in switching the shift range. Is to provide.

  A shift range switching device for an automatic transmission mounted on a vehicle according to a first invention includes a shift means for rotating an actuator to switch a shift position to one of a plurality of shifts, and a shift switched by the shift means. A storage means for storing the position; a first restriction means for restricting rotation of the actuator in a predetermined direction at a first shift position of the plurality of shift positions; and for controlling rotation of the actuator. And a first position setting means for setting the position where the rotation of the actuator is stopped by the first restricting means as a first reference position in the first shift position. In order to permit the start or interruption of power supply to the shift range switching device at the first shift position In the case where the shift position stored by the power control means and the storage means is unknown, when the power supply is started or shut down again after the power supply is cut off, the first reference position is set by the first position setting means. And a reference position resetting means for resetting.

  According to the first invention, in order to turn off the ignition switch of the vehicle, which is a switch for supplying electric power to the electrical equipment of the vehicle including the shift range switching device, the first shift position (for example, the P position) is set. Since it is necessary to be switched, it is always in the first shift position when the ignition switch is turned on again. Here, the rotational force of the actuator at the time of detecting the first reference position (for example, the P wall position corresponding to the P position) from the first shift position is compared with that at the time of detecting the first reference position from the non-P position. And small. Therefore, the detection of the first reference position from the first shift position has a low load on the first restricting means (for example, a detent spring that engages with the detent plate). That is, by setting the first reference position from the first shift position, the deformation of the detent spring can be prevented or reduced. Since the deformation of the detent spring can be prevented or reduced, the durability of the shift switching mechanism is improved by correctly setting the reference position in the first shift position. As a result, the load applied to the shift range switching mechanism can be reduced. Further, the rotation of the actuator is controlled by the control means, and the shift position is switched. In the first shift position, the reference position can be set by restricting rotation of the actuator in a predetermined direction by the restricting means. This eliminates the need for a neutral start switch.

  In the shift range switching device for an automatic transmission according to the second invention, in addition to the configuration of the first invention, the second shift position of the plurality of shift positions has a direction different from a predetermined direction of the actuator. The control device further includes a second restricting means for restricting the rotation, and the control means performs a second shift on the position where the rotation of the actuator is stopped by the second restricting means in response to the resetting of the first reference position. Second position setting means for setting as a second reference position in the position, first reference position reset by the reference position resetting means, and second set by the second position setting means Further included is a movable range calculating means for calculating a movable range of the actuator based on the reference position.

  According to the second invention, after the first reference position in the first shift position is set, the second reference position in the second shift position (for example, the non-P position) is set. Then, the movable range of the actuator is calculated based on the set first reference position and second reference position. By detecting the first reference position from the first shift position, the first reference position can be set more correctly, so that the movable range can be calculated more correctly and the load on the shift means is reduced. it can.

  In the shift range switching device of the automatic transmission according to the third invention, in addition to the configuration of the first invention, the control means is based on the first reference position reset by the reference position resetting means, A means for determining a first target rotational position at the time of switching to the first shift position by the actuator is further included.

  According to the third aspect, after the first reference position at the first shift position is set, the first target rotational position at the first shift position is determined based on the first reference position. Since the first reference position can be set more correctly by detecting the first reference position from the first shift position, the first target rotational position can be determined more correctly, and the shift means The load on can be reduced.

  In the shift range switching device for an automatic transmission according to the fourth invention, in addition to the configuration of the third invention, the second shift position of the plurality of shift positions has a direction different from the predetermined direction of the actuator. The control means further includes a second restriction means for restricting the rotation, and the control means stops the rotation of the actuator by the second restriction means in response to the resetting of the first reference position by the reference position resetting means. A second position setting means for setting the position as a second reference position in the second shift position, and a second when the actuator switches to the second shift position based on the second reference position. And a means for determining a target rotational position.

  According to the fourth invention, after the first reference position in the first shift position is set, the second reference position in the second shift position is set, and based on the set second reference position By determining the second target rotational position, the second target rotational position can be determined more correctly, and the load on the shift means can be reduced.

  In the shift range switching device for an automatic transmission according to the fifth invention, in addition to any one of the first to fourth inventions, in order to obtain a count value corresponding to the amount of rotation of the actuator. The position setting means includes means for setting a reference position of the actuator by detecting a state in which the minimum value or the maximum value of the count value acquired by the counting means does not change for a predetermined time. .

  According to the fifth invention, the counting means (for example, an encoder) acquires the rotation amount of the actuator. Then, a reference position corresponding to each shift position is set in response to the minimum value or maximum value of the acquired count value not changing for a predetermined time. As a result, even if the counting means is an encoder that can acquire only relative position information, the actuator can be appropriately controlled to rotate based on the reference position. And the load accompanying rotation of an actuator can be reduced and a shift position can be suitably switched using a shift means. Further, since it is not necessary to use a potentiometer for detecting the absolute position, it is possible to reduce the cost.

  In the shift range switching device for an automatic transmission according to the sixth aspect of the invention, in addition to the configuration of the first aspect or the second aspect, the first restricting means may rotate the actuator in a predetermined direction using a detent spring. Includes means for regulating in the shrinking direction.

  According to the sixth invention, by setting the first restricting means (for example, the P wall of the detent plate) for restricting the rotation of the actuator in a predetermined direction for contracting the detent spring at the first shift position, The reference position in the first shift position can be set with reference to the P wall. That is, it is not necessary to set the reference position based on the count value of each shift position that is referenced using a detection circuit or the like that detects the position of the shift position such as a neutral switch. As a result, the reference position of the actuator at the first shift position can be set without using a neutral switch.

  In the shift range switching device for an automatic transmission according to the seventh aspect of the invention, in addition to the configuration of the second aspect or the fourth aspect, the first restricting means controls the rotation of the actuator in a predetermined direction using a detent spring. The second restricting means includes means for restricting rotation of the actuator in a direction different from a predetermined direction to a direction of pulling the detent spring.

  According to the seventh invention, in the first shift position, the first restricting means (for example, the P wall of the detent plate) for restricting the rotation of the actuator in a predetermined direction for contracting the detent spring is set. On the other hand, in the second shift position, a second restricting means (for example, a non-P wall of the detent plate) for restricting the rotation of the actuator in the direction opposite to the predetermined direction for pulling the detent spring is set. Thus, the reference position at the first shift position can be set with reference to the first restricting means, and the reference at the second shift position with reference to the second restricting means. The position can be set. That is, it is not necessary to set the reference position based on the count value of each shift position that is referenced using a detection circuit or the like that detects the position of the shift position such as a neutral switch. As a result, the reference position of the actuator can be set without using a neutral switch.

  In the shift range switching device for an automatic transmission according to the eighth aspect of the invention, in addition to any one of the first to seventh aspects, the first shift position is a parking mechanism driven by an actuator. The second shift position is a non-P position where the parking mechanism does not operate.

  According to the eighth invention, the first shift position is the P position. Therefore, the power supply is cut off at the P position. That is, when the power supply is normally cut off, the shift position when the power supply is restarted is always the P position. Therefore, when detecting the P wall position corresponding to the P position, it is always possible to detect the wall position from the P position to the P wall.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated. In the following description, “shift range” has the same meaning as “shift position”.

  FIG. 1 shows a configuration of a shift control system 10 according to the embodiment. The shift control system 10 of the present embodiment is used for switching the shift range of the vehicle. The shift control system 10 includes a P switch 20, a shift switch 26, a vehicle power switch 28, a vehicle control device (hereinafter referred to as “V-ECU”) 30, and a parking control device (hereinafter referred to as “P-ECU”). ) 40, actuator 42, encoder 46, shift control mechanism 48, display unit 50, meter 52, and drive mechanism 60. The shift control system 10 functions as a shift-by-wire system that switches the shift range by electrical control. Specifically, the shift control mechanism 48 is driven by the actuator 42 to switch the shift range.

  The vehicle power switch 28 is a switch for switching on / off of the vehicle power. The vehicle power switch 28 is not particularly limited, and is, for example, an ignition switch. An instruction received by the vehicle power switch 28 from a user such as a driver is transmitted to the V-ECU 30. For example, when the vehicle power switch 28 is turned on, power is supplied from an auxiliary battery (not shown), and the shift control system 10 is activated.

  The P switch 20 is a switch for switching the shift range between a parking range (hereinafter referred to as “P range”) and a range other than parking (hereinafter referred to as “non-P range”). Includes an indicator 22 for indicating to the driver, and an input unit 24 for receiving an instruction from the driver. The driver inputs an instruction to put the shift range into the P range through the input unit 24. The input unit 24 may be a momentary switch. The instruction from the driver received by input unit 24 is transmitted to P-ECU 40 through V-ECU 30 and V-ECU 30.

  The P-ECU 40 controls the operation of the actuator 42 that drives the shift control mechanism 48 to switch the shift range between the P range and the non-P range, and presents the current shift range state to the indicator 22. When the driver depresses the input unit 24 when the shift range is the non-P range, the P-ECU 40 switches the shift range to the P range and presents the indicator 22 that the current shift range is the P range.

  The actuator 42 is configured by a switched reluctance motor (hereinafter referred to as “SR motor”), and drives the shift control mechanism 48 in response to an instruction from the P-ECU 40. The encoder 46 rotates integrally with the actuator 42 and detects the rotation state of the SR motor. The encoder 46 of the present embodiment is a rotary encoder that outputs A-phase, B-phase, and Z-phase signals. The P-ECU 40 obtains a signal output from the encoder 46, grasps the rotation status of the SR motor, and controls energization for driving the SR motor.

  The shift switch 26 switches the shift range to a range such as a drive range (D), reverse range (R), neutral range (N), brake range (B), or when the P range is entered. It is a switch for canceling. The instruction from the driver received by the shift switch 26 is transmitted to the V-ECU 30. The V-ECU 30 performs control for switching the shift range in the drive mechanism 60 based on an instruction from the driver, and presents the current shift range state to the meter 52. The drive mechanism 60 is composed of a continuously variable transmission mechanism, but may be composed of a stepped transmission mechanism.

  The V-ECU 30 comprehensively manages the operation of the shift control system 10. The display unit 50 displays instructions and warnings for the driver issued by the V-ECU 30 or the P-ECU 40. The meter 52 presents the state of the vehicle equipment, the state of the shift range, and the like.

  FIG. 2 shows the configuration of the shift control mechanism 48. Hereinafter, the shift range means the P range and the non-P range, and does not include the R, N, D, and B ranges in the non-P range. The shift control mechanism 48 is fixed to the shaft 102 rotated by the actuator 42, the detent plate 100 rotating with the rotation of the shaft 102, the rod 104 operating with the rotation of the detent plate 100, and the output shaft of the transmission (not shown). A parking lock pole 106 for locking the parking gear 108, a detent spring 110 and a roller 112 for limiting the rotation of the detent plate 100 and fixing the shift range. The detent plate 100 functions as a shift unit that is driven by the actuator 42 to switch the shift range. The shaft 102, the detent plate 100, the rod 104, the detent spring 110, and the rollers 112 serve as a shift switching mechanism. The encoder 46 functions as a counting unit that acquires a count value corresponding to the rotation amount of the actuator 42.

  FIG. 2 shows a state when the shift range is the non-P range. In this state, since the parking lock pole 106 does not lock the parking gear 108, the rotation of the drive shaft of the vehicle is not hindered. When the shaft 42 is rotated clockwise by the actuator 42 from this state, the rod 104 is pushed in the direction of the arrow A shown in FIG. 2 via the detent plate 100, and parking is performed by the taper portion provided at the tip of the rod 104. The lock pole 106 is pushed up in the direction of arrow B shown in FIG. As the detent plate 100 rotates, one of the two valleys provided at the top of the detent plate 100, that is, the roller 112 of the detent spring 110 in the non-P range position 120, climbs over the mountain 122 and passes through the other valley. That is, the process moves to the P range position 124. The roller 112 is provided on the detent spring 110 so as to be rotatable in its axial direction. When the detent plate 100 rotates until the roller 112 reaches the P range position 124, the parking lock pole 106 is pushed up to a position where it engages with the parking gear 108. As a result, the drive shaft of the vehicle is mechanically fixed, and the shift range is switched to the P range.

  In the shift control system 10 according to the embodiment, the P-ECU 40 is configured so that the roller 112 of the detent spring 110 is used to reduce the load related to the shift switching mechanism such as the detent plate 100, the detent spring 110, and the shaft 102 when the shift range is switched. The amount of rotation of the actuator 42 is controlled so as to reduce the impact when the vehicle falls over the mountain 122 and falls.

  FIG. 3 shows the configuration of the detent plate 100. In each valley, the surface located on the side away from the mountain 122 is called a wall. That is, the wall exists at a position where the roller 112 of the detent spring 110 hits the roller 112 and falls into the valley when the roller 112 of the detent spring 110 falls over the valley 122 without performing the following control by the P-ECU 40. The wall at the P range position 124 is referred to as “P wall”, and the wall at the non-P range position 120 is referred to as “non-P wall”. When the roller 112 moves from the P range position 124 to the non-P range position 120, the P-ECU 40 controls the actuator 42 so that the non-P wall 210 does not collide with the roller 112. Specifically, the P-ECU 40 stops the rotation of the actuator 42 at a position before the non-P wall 210 collides with the roller 112. This position is referred to as a “non-P target rotational position”. When the roller 112 moves from the non-P range position 120 to the P range position 124, the P-ECU 40 controls the actuator 42 so that the P wall 200 does not collide with the roller 112. Specifically, the P-ECU 40 stops the rotation of the actuator 42 at a position before the P wall 200 collides with the roller 112. This position is called “P target rotation position”. By controlling the actuator 42 by the P-ECU 40, the load on the shift switching mechanism such as the detent plate 100, the detent spring 110, and the shaft 102 at the time of shift range switching can be significantly reduced. It is possible to reduce the weight and cost of the shift switching mechanism by reducing the load. In the present embodiment, the shift switching mechanism can be further reduced in weight and cost by performing the control described later.

  FIG. 4 is a diagram for explaining a control method of the actuator 42. The actuator 42 rotates the detent plate 100. The rotation of the actuator 42 is restricted by the P wall 200 and the non-P wall 210. FIG. 4 conceptually shows the position of the P wall 200 and the position of the non-P wall 210 when the rotation control of the actuator 42 is performed. The range from the P wall position to the non-P wall position is referred to as a movable rotation amount of the actuator 42. The movable rotation amount includes an actual movable rotation amount obtained from the count value of the encoder 46 (hereinafter referred to as “actual movable rotation amount”) and a movable rotation amount determined by design (hereinafter referred to as “designed movable rotation amount”). Call).

  The current shift range is determined when it is within a predetermined rotation amount range from the P wall position or the non-P wall position. As a shift range determination criterion, a P lock determination position and a P release determination position are set, and a range from the P wall position to the P lock determination position and a range from a non-P wall position to the P release determination position are defined as a shift range determination range. And Specifically, when the rotation amount of the actuator 42 detected by the encoder 46 is in the range from the P wall position to the P lock determination position, it is determined that the shift range is the P range, while the rotation amount of the actuator 42 is Is within the range from the non-P wall position to the P release determination position, it is determined that the shift range is the non-P range. When the rotation amount of the actuator 42 is between the P lock determination position and the P release determination position, it is determined that the shift range is indefinite or the shift is being switched. The above determination is performed by the P-ECU 40.

  The P target rotation position is set between the P wall position and the P lock determination position. The P target rotation position is a position where the P wall 200 does not collide with the roller 112 of the detent spring 110 when switching from the non-P range to the P range, and is determined with a predetermined margin from the P wall position. The margin is set with a margin in consideration of looseness due to changes over time. As a result, the change with time can be absorbed if the number of times of use is a certain number of times, and collision with the P wall 200 and 112 at the time of shift range switching can be avoided.

  Similarly, the non-P target rotation position is set between the non-P wall position and the P release determination position. The non-P target rotation position is a position where the non-P wall 210 does not collide with the roller 112 of the detent spring 110 when switching from the P range to the non-P range, and is determined with a predetermined margin from the non-P wall position. The margin is set with a margin in consideration of the backlash due to changes over time, etc., so that changes over time can be absorbed if the number of times of use is a certain number of times, and collision with the non-P wall 210 and 112 at the time of shift range switching is avoided. can do. Note that the margin from the non-P wall position and the margin from the P wall position do not have to be the same, and may differ depending on the shape of the detent plate 100 and the like.

  As described above, the control method of the actuator 42 has been shown on the assumption that the P wall position and the non-P wall position are detected. The P wall position or the non-P wall position is a reference position for determining the shift range determination range and the target rotation position at the P range position 124 or the non-P range position 120. Hereinafter, a method of controlling the position of the actuator 42 using the encoder 46 that detects relative position information, specifically, a method of detecting the wall position serving as the reference position will be described.

  The P-ECU 40 or the V-ECU 30 stores the shift range when the vehicle power switch 28 was previously turned off. When the vehicle power switch 28 is turned on, the P-ECU 40 sets the stored shift range to the current shift range. Wall position detection control detects the wall position in the current shift range. If the previous shift range is not stored, the V-ECU 30 determines the current shift range based on the vehicle speed. Specifically, for example, when the vehicle speed is at a low speed of 3 km / h or less, the V-ECU 30 determines the current shift range as the P range, and when the vehicle speed is at a medium to high speed higher than 3 km / h, The shift range is defined as a non-P range. Note that the case where the vehicle speed is medium to high without storing the previous shift range is equivalent to a situation where the power supply is momentarily interrupted while the vehicle is running and the current shift range data is lost. To do. In most cases, when the vehicle power switch 28 is turned on, it is determined that the vehicle speed is low, and the current shift range is determined as the P range.

  FIG. 5A is a diagram for explaining a control method for detecting the P wall position. The P-ECU 40 functions as a rotation control unit that rotates the actuator 42 and a position setting unit that sets the P wall position of the actuator 42, that is, a reference position. In the P wall position detection control, first, the actuator 42 rotates the detent plate 100 in the clockwise direction, that is, in the direction in which the P wall 200 faces the roller 112 of the detent spring 110, thereby bringing the roller 112 and the P wall 200 into contact with each other. The P wall 200 functions as a restricting means for restricting the clockwise rotation of the actuator 42 at the P range position. The P wall 200 may constitute a restricting means in cooperation with the detent spring 110 and the roller 112. In FIG. 5A, an arrow F1 indicates a rotational force by the actuator 42, an arrow F2 indicates a spring force by the detent spring 110, and an arrow F3 indicates a pushing back force by the rod 104. A detent plate 100 ′ indicated by a dotted line indicates a position where the P wall 200 and 112 are in contact with each other. Therefore, detecting the position of the detent plate 100 ′ corresponds to detecting the position of the P wall 200.

  The detent plate 100 is rotated against the spring force of the detent spring 110 in the clockwise direction by the rotational force F1 of the actuator 42 from the position indicated by the dotted line even after contact with the P wall 200 and 112. As a result, the detent spring 110 is deflected, the spring force F2 is increased, and the pushing back force F3 by the rod 104 is also increased. The rotation of the detent plate 100 stops when the rotational force F1 is balanced with the spring force F2 and the pushing back force F3.

  The rotation stop of the detent plate 100 is determined based on the state of the count value acquired by the encoder 46. The P-ECU 40 determines whether the rotation of the detent plate 100 and the actuator 42 is stopped when the minimum value or the maximum value of the count value of the encoder 46 does not change for a predetermined time. Whether to monitor the minimum value or the maximum value of the count value may be set according to the encoder 46. In any case, the fact that the minimum value or the maximum value does not change for a predetermined time indicates that the detent plate 100 moves. Indicates a missing state.

  The P-ECU 40 detects the position of the detent plate 100 when rotation is stopped as a provisional P wall position (hereinafter referred to as “provisional P wall position”), and calculates the deflection amount or the deflection angle of the detent spring 110. . The calculation of the deflection amount or the deflection angle is performed using a map that is held in advance in the P-ECU 40 and shows the relationship between the deflection amount or the deflection angle corresponding to the voltage applied to the actuator 42. The P-ECU 40 calculates a deflection amount or a deflection angle corresponding to a voltage applied to the actuator 42 when the temporary P wall position is detected from the map. Instead of the applied voltage of the actuator 42, a map using a battery voltage may be used. The battery voltage is monitored by the P-ECU 40 and can be easily detected. In this case, the map is created in consideration of the voltage drop due to the wire harness from the battery to the actuator 42. Using this map, the P-ECU 40 performs map correction on the temporary P wall position from the calculated deflection amount or deflection angle, and determines the map corrected position as the P wall position. By determining the P wall position, the P lock determination position and the P target rotation position can be set. Instead of the map indicating the relationship between the deflection amount or the deflection angle with respect to the applied voltage, a map indicating the relationship between the deflection amount or the deflection angle corresponding to the output torque of the actuator 42 may be used. Instead, a sensor that detects the amount of deflection or the angle of deflection may be provided to detect it.

  FIG. 5B is a diagram for explaining a control method for detecting a non-P wall position. The P-ECU 40 functions as a rotation control unit that rotates the actuator 42 and a position setting unit that sets a non-P wall position of the actuator 42, that is, a reference position. In the non-P wall position detection control, first, the actuator 42 rotates the detent plate 100 in the counterclockwise direction, that is, in the direction in which the non-P wall 210 faces the roller of the detent spring 110, thereby bringing the roller 112 into contact with the non-P wall 210. . The non-P wall 210 functions as a restricting means for restricting the counterclockwise rotation of the actuator 42 at the non-P range position. The non-P wall 210 may constitute a restricting means in cooperation with the detent spring 110 and the roller 112. In FIG. 5B, the arrow F <b> 1 indicates the rotational force by the actuator 42, the arrow F <b> 2 indicates the spring force by the detent spring 110, and the arrow F <b> 3 indicates the tensile force by the rod 104. A detent plate 100 ″ indicated by a dotted line indicates a position where the non-P wall 210 and 112 are in contact with each other. Therefore, detecting the position of the detent plate 100 ″ corresponds to detecting the position of the non-P wall 210.

  The detent plate 100 is rotated counterclockwise against the tensile force of the detent spring 110 by the rotational force F1 of the actuator 42 from the position indicated by the dotted line even after contact with the non-P wall 210 and 112. As a result, the detent spring 110 is extended, the spring force F2 is increased, and the tensile force F3 is also increased by the rod 104. When the rotational force F1 is balanced with the spring force F2 and the tensile force F3, the rotation of the detent plate 100 stops.

  The rotation stop of the detent plate 100 is determined based on the count value acquired by the encoder 46. Specifically, when the maximum value or the minimum value of the count value of the encoder 46 does not change for a predetermined time, it is determined that the rotation of the detent plate 100 and the actuator 42 is stopped.

  The P-ECU 40 detects the position of the detent plate 100 when rotation is stopped as a temporary non-P wall position (hereinafter referred to as “provisional non-P wall position”), and calculates the extension amount of the detent spring 110. . The calculation of the extension amount is performed using a map that is held in advance in the P-ECU 40 and shows the relationship of the extension amount corresponding to the voltage applied to the actuator 42. The P-ECU 40 calculates the extension amount corresponding to the voltage applied to the actuator 42 when the temporary non-P wall position is detected from the map. The P-ECU 40 uses this map to map-correct the temporary non-P wall position from the calculated extension amount, and determines the map-corrected position as the non-P wall position. By determining the non-P wall position, the P release determination position and the non-P target rotation position can be set. Instead of a map showing the relationship of the extension amount to the applied voltage, a map showing the relationship of the extension amount corresponding to the output torque of the actuator 42 may be used, or instead of calculating using the map, the extension amount is calculated. You may make it detect by providing the sensor to detect.

  As described above, in the wall position detection control, the wall position in the current shift range is detected. When the actual movable rotation amount between the P wall position and the non-P wall position has already been detected, the wall position in the other shift range can also be calculated using this actual movable rotation amount. The actual movable rotation amount is obtained by performing wall position detection control in one shift range to detect the wall position, and then performing wall position detection control in the other shift range to detect the other wall position. The range between the positions can be measured. The P-ECU 40 stores the measured actual movable rotation amount. Once the actual movable rotation amount is acquired, when the P-ECU 40 detects the wall position in one shift range, the position rotated by the actual movable rotation amount from the wall position is set as the wall position in the other shift range. It is possible to set the shift range range and the target rotation position in the two shift ranges.

  From the above, the wall positions of both the P range and the non-P range may be detected when the P-ECU 40 does not store the actual movable rotation amount. For example, the positions of both walls are detected when the vehicle is shipped from the factory or when data in the P-ECU 40 is lost. Further, even when the actual movable rotation amount is stored, the detection control of the both wall positions may be performed every predetermined number of switching times or the number of trips. For example, when the shift range is switched tens of thousands of times, the amount of play due to wear increases, and an error also occurs in the actual movable rotation amount. Therefore, the wall position detection corresponding to the change with time can be performed by measuring the actual movable rotation amount again. Further, it may be performed each time the vehicle power switch 28 is turned on, or when the abnormality of the actuator 42 occurs in the previous trip, for example, both wall position detection control is performed to actually move the rotation. The amount may be calculated.

  One trip may be defined as from when the vehicle power switch is turned on to off, or may be defined as from when the vehicle power supply of the vehicle is actually turned on to when it is turned off.

  FIG. 6 shows an example of wall position detection control performed using data stored in the previous trip. When the shift range at the end of the previous trip is in the P range, the P wall position detection control is performed first. If the actual movable rotation amount has been detected, the non-P wall position detection control is not performed. On the other hand, when the actual movable rotation amount is unknown, non-P wall position detection control is performed. The detection control of the non-P wall position is performed when a request for switching to the non-P range is made by a driver operation. At this time, the P-ECU 40 performs the non-P wall position detection control by switching the shift range to the non-P range and bringing the non-P wall 210 and the roller 112 of the detent spring 110 into contact with each other. After detecting both wall positions, the P-ECU 40 measures and stores the actual movable rotation amount.

  When the shift range at the end of the previous trip is in the non-P range, the non-P wall position detection control is first performed. If the actual movable rotation amount has been detected, the P wall position detection control is not performed. On the other hand, when the actual movable rotation amount is unknown, P wall position detection control is performed. The P wall position detection control is performed when a request for switching to the P range is made by a driver operation. The P-ECU 40 performs the P wall position detection control by switching the shift range to the P range and bringing the P wall 200 and the roller 112 of the detent spring 110 into contact with each other. After detecting both wall positions, the P-ECU 40 measures and stores the actual movable rotation amount.

  If the shift range at the end of the previous trip is unknown, the V-ECU 30 determines the current shift range based on the vehicle speed and sends a wall position detection command to the P-ECU 40. If it becomes clear from the command that the current shift range is set to the P range, the P-ECU 40 first performs detection control of the P wall position, and then receives a shift switching request from the user to determine the non-P wall position. Perform detection control. On the other hand, when it is determined by the command that the current shift range is set to the non-P range, the P-ECU 40 first performs control to detect the non-P wall position, and then receives a shift switching request from the user to receive the P wall. Position detection control is performed.

  FIG. 7 shows an example of a method for calculating the target rotational position of the actuator 42. In FIG. 7, the case where the count value by the encoder 46 counts up in the direction from the P wall position toward the non-P wall position is taken as an example. When the P wall position, the non-P wall position, and the actual movable rotation amount have been detected, the P target rotation position is set as (P wall position + margin), and the non-P target rotation position is set as (non-P wall position−margin). ) And set.

  When the P wall position has been detected and the non-P wall position is unknown, if the actual movable rotation amount has been detected, the P target rotation position is set as (P wall position + margin), and non-P The target rotation position is set as (P wall position + actual movable rotation amount−margin). When the actual movable rotation amount is unknown, the P target rotation position is set as (P wall position + margin), and the non-P target rotation position is set as (P wall position + designed movable rotation amount). To do. The design movable rotation amount is set to a value that takes into account the margin.

  If the P wall position is unknown and the non-P wall position has been detected, if the actual movable rotation amount has been detected, the P target rotation position is expressed as (non-P wall position−actual movable rotation amount + margin). And the non-P target rotation position is set as (non-P wall position−margin). Further, when the actual movable rotation amount is unknown, the P target rotation position is set as (non-P wall position−designed movable rotation amount), and the non-P target rotation position is set as (non-P wall position−margin). And set.

  In another example, the count value by the encoder 46 may be counted up in the direction from the non-P wall position to the P wall position. In this case, when the non-P wall position, the P wall position, and the actual movable rotation amount have been detected, the non-P target rotation position is set to (non-P wall position + margin), and the P target rotation position is set to (P wall Position-margin).

  When the non-P wall position has been detected and the P wall position is unknown, if the actual movable rotation amount has been detected, the non-P target rotation position is set as (non-P wall position + margin) The P target rotation position is set as (non-P wall position + actual movable rotation amount−margin). When the actual movable rotation amount is unknown, the non-P target rotation position is set as (non-P wall position + margin), and the P target rotation position is set as (non-P wall position + design movable rotation amount). And set.

  If the non-P wall position is unknown and the P wall position has already been detected, if the actual movable rotation amount has been detected, the non-P target rotation position is expressed as (P wall position−actual movable rotation amount + margin). And the P target rotation position is set as (P wall position−margin). When the actual movable rotation amount is unknown, the non-P target rotation position is set as (P wall position−designed movable rotation amount), and the P target rotation position is set as (P wall position−margin). To do.

  As described above, the shift control system 10 rotates the actuator 42 to bring the wall of the detent plate 100 into contact with the roller 112 of the detent spring 110. And the wall position of the detent plate 100 corresponding to the reference position of the shift range is detected by detecting the contact position. By setting this wall position as the reference position, the rotation of the actuator 42 can be appropriately controlled even when using the encoder 46 that can detect only relative position information. That is, the shift range can be appropriately switched without using a neutral start switch or the like. Here, when the shift range is switched by this method, (1) the rotation of the actuator 42 is controlled to the position where the shift range is switched. (2) In order to improve durability, in the shift range switching operation, the rotation of the actuator 42 is stopped before hitting the wall of the detent plate 100. In order to satisfy these (1) and (2), it is necessary to learn the actual movable rotation amount of the actuator 42 when switching the shift range.

  However, in the detection of the P wall position, the detent spring 110 is contracted. On the other hand, in the detection of the non-P wall position, the detent spring 110 is pulled. Therefore, when detecting the wall position, a difference occurs in the deformation of the spring between the case where the wall position in the same range as the shift range at the start of detection is detected and the case where the wall position in a different range is detected. Therefore, it is conceivable that the actual movable rotation amount varies depending on the shift range where detection is started.

  FIG. 8 is a diagram illustrating an example of a time chart of a change in the count number of the encoder 46 when the wall position is detected by wall contact from the non-P range to the P wall. In the time chart of FIG. 8, the horizontal axis represents time. On the other hand, the vertical axis indicates the count number of the encoder 46. In this case, the maximum count value of the encoder 46 indicates the non-P wall position where the roller 112 contacts the non-P wall 210 of the detent plate 100. On the other hand, the minimum value of the count number of the encoder 46 indicates the P wall position where the roller 112 contacts the P wall 200 of the detent plate 100. At this time, referring to FIG. 8, when the wall is applied from the non-P range to the P wall, the detent spring 110 bends in response to the roller 112 contacting the P wall 200 of the detent plate 100. As a result, it can be seen that the detent spring 110 is contracted. This is due to the large rotational force when the wall is applied from the non-P range to the P wall. That is, it is conceivable that the rotational force from the non-P range to the P wall includes an impact force when the detent plate 100 climbs over the mountain 122 and falls into the valley in addition to the output torque of the actuator 42. Therefore, there is a possibility of erroneous learning of the P wall position. Due to mislearning of the P wall position, the calculated target rotation position and actual movable rotation amount are deviated, so that there is a possibility of hitting the wall of the detent plate 100 during normal switching. That is, it can be said that the load on the detent spring 110 increases. Therefore, the detection of the P wall position is more preferably the wall contact from the P range to the P wall than the wall contact from the non-P range to the P wall.

  Therefore, for example, when the current shift range is in an unknown state, the P wall position is detected by the wall contact learning from the non-P range to the P wall. there is a possibility. As a result, the actual movable rotation amount may be erroneously learned. Therefore, in the embodiment of the present invention, when the current shift range is unknown, the actual movable rotation amount is redetected on the second trip.

  That is, it is assumed that the power source of the P-ECU 40 or the power source of the vehicle cannot be shut off unless it is switched to the P range. For example, when power supply to the shift control system 10 is started by turning on the vehicle power switch 28, that is, when the power is turned on in the first trip, it is stored in an internal memory of the P-ECU 40 (not shown). Assume that the current shift range is unknown. At this time, when the user switches to the P range and the power is turned off and then the power is turned on again (second trip), the user always switches to the P range. Therefore, it is possible to re-detect the P wall position by learning to hit the wall from the P range to the P wall. As a result, the actual movable rotation amount can be detected again.

  The “state in which the current shift range is unknown” includes, for example, a state in which the shift range stored in the internal memory of the P-ECU 40 is erased by battery clear or the like.

  Hereinafter, referring to the flowchart of FIG. 9, when the shift range is unknown when the power is turned on in the first trip, the actual movable rotation amount is detected in response to the power being turned on in the second trip. Will be described.

  In step (hereinafter, step is abbreviated as S) 100, the vehicle is turned on in response to a user operation on vehicle power switch 28. That is, power supply to the shift control system 10 is started.

  In S102, P-ECU 40 determines the current shift range based on the shift range stored in the internal memory in the previous trip. At this time, the P-ECU 40 waits until a switching request is received from the V-ECU 30 because the current shift range is unknown due to, for example, battery clear. Then, the V-ECU 30 determines the current shift range from the vehicle speed. That is, for example, the V-ECU 30 determines that the current shift range is the P range when the vehicle speed is 3 km / h or less. Then, the V-ECU 30 sends a P range switching request signal to the P-ECU 40. Here, the internal memory of the P-ECU 40 includes a rewritable nonvolatile memory. The nonvolatile memory is, for example, an SRAM (Static Random Access Memory).

  For example, when the vehicle speed is 3 km / h or higher, the V-ECU 30 determines that the current shift range is the non-P range. For example, this may be the case when the power is turned off for some reason during traveling and the power is turned on again. At this time, the V-ECU 30 sends a non-P range switching request signal to the P-ECU 40.

  In S104, P-ECU 40 determines whether or not there is a switching request signal from V-ECU 30. If there is a shift range switching request signal (YES in S104), the process proceeds to S106. If not (NO in S104), the process returns to S102.

  In S106, when there is a shift range switching request signal from V-ECU 30, P-ECU 40 performs phase alignment between the rotor and the energized phase in encoder 46 as an initial drive operation.

  In S108, P-ECU 40 detects the wall position by wall pad learning in the shift range requested to be switched from V-ECU 30. That is, for example, when the V-ECU 30 determines that the current shift range is the P range based on the vehicle speed, the V-ECU 30 sends a P range switching request signal to the P-ECU 40. send. Then, the P-ECU 40 performs wall contact learning from the P range to the P wall with the current shift range as the P range. Alternatively, when the V-ECU 30 determines that the current shift range is the non-P range, the P-ECU 40 similarly performs the wall contact learning from the non-P range to the non-P wall.

  When the wall position is detected in S110, the P-ECU 40 drives the actuator 42 to a position separated from the wall position by a margin, and then turns off the energization to the actuator 42. That is, the P-ECU 40 calculates the target rotational position based on the detected wall position. Then, the P-ECU 40 rotates the detent plate 100 by driving the actuator 42 to adjust the rollers 112 to the calculated target rotation position.

  In S112, P-ECU 40 stands by until there is a shift range switching signal from the user.

  In S114, P-ECU 40 determines whether or not there is a switching request from the user. If there is a switching request from the user (YES in S114), the process proceeds to S115. If not (NO in S114), the process proceeds to S124.

  In S115, when there is a range switching request from the user, the P-ECU 40 causes the actuator 42 to rotate a predetermined amount of rotation in the requested range direction. Here, the predetermined rotation amount is the rotation amount that does not hit the wall corresponding to the requested range. That is, the predetermined rotation amount may be the rotation amount to the target rotation position corresponding to the requested range calculated based on the design movable rotation amount.

  In S116, P-ECU 40 determines whether or not the actual movable rotation amount is stored in the internal memory. If there is a storage of the actual movable rotation amount in the internal memory (YES in S116), the process proceeds to S124. If not (NO in S116), the process proceeds to S118.

  In S118, P-ECU 40 detects the wall position by wall pad learning in the shift range for which a switching request is received from V-ECU 30. That is, for example, when there is a non-P range switching request from the user, the P-ECU 40 rotates the actuator to switch the shift range from the P range to the non-P range. Then, the P-ECU 40 detects a non-P wall position.

  In S120, P-ECU 40 calculates the actual movable rotation amount based on the wall position detected in S108 and the wall position detected in S118. Then, the P-ECU 40 stores the calculated actual movable rotation amount in the internal memory.

  When the wall position is detected in S122, the P-ECU 40 drives the actuator 42 to a position separated from the wall position by a margin, and then turns off the energization to the actuator 42. That is, the P-ECU 40 calculates the target rotational position based on the detected wall position. Then, the P-ECU 40 rotates the detent plate 100 by driving the actuator 42 to adjust the rollers 112 to the calculated target rotation position.

  In S124, a request to shut off the power is received in response to the user's operation on the vehicle power switch 28.

  In S126, P-ECU 40 determines whether or not the current shift range is the P range. If the current shift range is P range (YES in S126), the process proceeds to S128. If not (NO in S126), the process returns to S112.

  In S128, when P-ECU 40 determines that the current shift range is the P range, V-ECU 30 permits the power supply to be shut off. Then, the V-ECU 30 turns off the vehicle. The storage of the shift range in the internal memory of the P-ECU 40 is not particularly limited, but may be stored every time a switching request signal is received from the V-ECU 30 or the user, and the power is turned off. It may be stored when it is done.

  In S130, the vehicle is turned on for the second time in response to a user operation on vehicle power switch 28.

  In S132, since the shift range is stored in the previous trip in the second trip, the initial standby for performing the standby operation is performed until a switching request is received from V-ECU 30. At this time, since the power supply cannot be shut off unless it is switched to the P range at the end of the previous trip, the shift range stored in the internal memory of the P-ECU 40 is the P range in the second trip.

  In S134, the encoder 46 performs phase alignment between the rotor and the energized phase as an initial drive operation.

  In S136, P-ECU 40 detects the wall position by wall pad learning based on the shift range stored in the previous trip. That is, in the P range, the P-ECU 40 detects the P wall position from the P range.

  When the P wall position is detected in S138, the P-ECU 40 calculates a P target rotation position separated from the P wall position by a margin. Then, the P-ECU 40 drives the actuator 42 to align the roller 112 with the calculated P target rotation position. Thereafter, the P-ECU 40 turns off the energization of the actuator 42.

  In S140, P-ECU 40 determines whether or not there is a shift range switching request from the user. If there is a shift range switching request from the user (YES in S140), the process proceeds to S142. If not (NO in S140), it waits until there is a shift range switching request from the user.

  In S142, when there is a range switching request from the user, the P-ECU 40 causes the actuator 42 to rotate by a predetermined rotation amount in the non-P range direction. Here, the predetermined rotation amount is a rotation amount that does not hit the non-P wall. That is, the predetermined rotation amount may be a rotation amount to a non-P target rotation position calculated based on the actual movable rotation amount calculated in the first trip, or a non-P target calculated based on the design movable rotation amount. The rotation amount up to the rotation position may be used.

  In S144, P-ECU 40 performs wall pad learning from the non-P range to the non-P wall. That is, the P-ECU 40 detects a non-P wall position.

  At S146, the actual movable rotation amount is calculated and stored based on the detected P wall position and non-P wall position.

  When the non-P wall position is detected in S148, the P-ECU 40 calculates a non-P target rotational position separated from the non-P wall position by a margin. Then, the P-ECU 40 drives the actuator 42 to align the roller 112 with the calculated non-P target rotational position. Thereafter, the P-ECU 40 turns off the energization of the actuator 42.

  An operation in shift control system 10 according to the present embodiment based on the above-described structure and flowchart will be described in detail with reference to the time chart of FIG.

  FIG. 10A is a diagram showing a switch request signal sent to the P-ECU 40. The switching request signal is sent to the P-ECU 40 based on an instruction from the user or an instruction from the V-ECU 30. At this time, if a switching request signal is not sent, the switching request signal is in an unknown state. FIG. 10B is a diagram showing changes in the control mode. The control mode includes at least a mode when the power is turned on and a control mode for detecting the non-P wall position. FIG. 10C is a diagram showing a change in the number of counts acquired by the encoder 46. Further, FIG. 10D is a diagram showing the current shift range.

  Referring to FIG. 10B, when the user turns on the power using vehicle power switch 28 (S100), P-ECU 40 is switched from V-ECU 30 because the shift range stored in the internal memory is unknown. The initial standby operation is performed until a request is received (S102). Then, the V-ECU 30 determines that the current shift range is the P range because it is in a stopped state. At this time, referring to FIG. 10A, P-ECU 40 receives a P range switching request from V-ECU 30 (YES in S104). Then, the encoder 46 performs phase alignment between the rotor and the energized phase (S106). Referring to FIG. 10C, P-ECU 40 performs wall pad learning from the P range to the P wall (S108). When the P wall position is detected, the P-ECU 40 rotates the actuator 42 until the roller 112 reaches the P target rotation position rotated by a predetermined margin from the P wall position in the non-P range direction (S110). At this time, the P-ECU 40 stands by until a switching request is received from the user (S112), and referring to FIG. 10A again, if there is a switching request from the user to the non-P range (YES in S114). ), The range switching operation is performed (S115), and if the actual movable rotation amount is not stored (NO in S116), the non-P range wall pad learning control mode is set again with reference to FIG. 10B. (S118). When the non-P range wall position is detected, the P-ECU 40 calculates the actual movable rotation amount based on the P range wall position and the non-P range wall position. Then, the P-ECU 40 stores the calculated actual movable rotation amount in the internal memory (S120). Referring to FIG. 10C again, P-ECU 40 rotates actuator 42 until roller 112 reaches a non-P target rotation position that is rotated by a predetermined margin in the direction of P range from the non-P wall position. (S122). When receiving a power-off request from the user (S124), if the current shift range is a non-P range (NO in S126), the P-ECU 40 again waits for a shift range switching request from the user. (S112). Referring to FIG. 10A again, in response to a request for switching to the P range by the user (YES in S114), since the actual movable rotation amount is stored (YES in S116), the power supply from the user is shut off. When the current shift range is the P range (YES in S126), the V-ECU 30 shuts off the power (S128).

  Then, referring to FIG. 10B again, when the power is turned on for the second time in response to a power-on request from the user (S130), P-ECU 40 stores the previous shift range in the internal memory. Since it is stored, the initial standby operation is passed (S132). Then, the encoder 46 performs phase alignment between the rotor and the energized phase (S134). At this time, referring to FIG. 10C again, since the current shift range is the P range, the P-ECU 40 detects the P wall position by P wall pad learning (S136). When the P wall position is detected, the P-ECU 40 rotates the actuator 42 until the roller 112 reaches the P target rotation position (S138). Then, referring to FIG. 10A again, when the user requests switching to the non-P range (YES in S140), P-ECU 40 performs the range switching operation (S142), and again in FIG. Referring to B), the non-P wall position is detected in the non-P range (S144). Then, when the non-P wall position is detected, the P-ECU 40 calculates the actual movable rotation amount of the actuator 42 based on the P wall position and the non-P wall position, and stores it in the internal memory (S146). ), The actuator 42 is rotated until the roller 112 reaches the non-P target rotation position (S148).

  Thereafter, in response to a P range switching request from the user, the P-ECU 40 performs a range switching operation. In the P range, when the user requests to shut off the power, the V-ECU 30 Shut off.

  Then, when the power is turned on for the third time by the user, the current shift range and the actual movable rotation amount are stored in the memory inside the P-ECU 40. Therefore, referring to FIG. If there is a switching request from the user after learning the wall position, the range switching operation is performed but the non-P wall position is not detected.

  When the power is turned on for the second time after the battery is cleared (second trip), if the shift range is other than P, for example, when the actuator 42 is abnormal, or the actuator is running even if it is normal When the power is shut off for some reason and the power is restored again, the P-ECU 40 performs detection control of both wall positions and calculates the target rotational position and the actual movable rotational amount in the next trip.

  As described above, the shift control system 10 according to the embodiment of the present invention eliminates the need for a neutral switch and has the following effects. That is, in the shift control system 10, since the power is not turned off unless it is switched to the P range, it is always in the P range when the power is turned on again. At that time, since the rotational force of the actuator 42 is smaller than the detection of the P wall position from the non-P range by detecting the P wall position in the P range, the deformation of the detent spring 110 is prevented or reduced. Since the deformation of the detent spring 110 is prevented or reduced, the reference position in the P range is correctly detected, and the actual movable rotation amount based on the P wall position, the P target rotation position, and the non-P target rotation position are also correctly learned. . Further, when the shift range is correctly switched, the durability of the shift switching mechanism 48 is also improved.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a figure which shows the structure of the shift control system 10 which concerns on this Embodiment. 3 is a diagram showing a configuration of a shift control mechanism 48. FIG. FIG. 3 is a diagram showing a configuration of a detent plate 100. 4 is a diagram for explaining a control method of the actuator 42. FIG. It is a figure for demonstrating the control method which detects a P wall position, and a figure for demonstrating the control method which detects a non-P wall position. It is a figure which shows the example of wall position detection control. It is a figure which shows the example of the calculation method of the target rotational position of the actuator. It is a figure which shows the example of the time chart of the change of the count number of the encoder 46 at the time of wall position detection by the wall contact from a non-P range to a P wall. 3 is a flowchart showing a control structure of a program executed by P-ECU 40. It is a figure which shows the example of the time chart of operation | movement of the shift control system 10 which concerns on embodiment of this invention.

Explanation of symbols

  10 shift control system, 20 P switch, 22 indicator, 24 input unit, 26 shift switch, 28 vehicle power switch, 30 V-ECU, 40 P-ECU, 42 actuator, 46 encoder, 48 shift control mechanism, 50 display unit, 52 meter, 60 drive mechanism, 100 detent plate, 102 shaft, 104 rod, 106 parking lock pole, 108 parking gear, 110 detent spring, 112 rollers, 120 non-P range position, 122 mountain, 124 P range position, 200 P wall 210 non-P walls.

Claims (8)

A shift range switching device for an automatic transmission mounted on a vehicle,
Shift means for rotating the actuator to switch the shift position to one of a plurality;
Storage means for storing the shift position switched by the shift means;
First restriction means for restricting rotation of the actuator in a predetermined direction at a first shift position of the plurality of shift positions;
Control means for controlling the rotation of the actuator,
The control means includes
First position setting means for setting a position at which rotation of the actuator is stopped by the first restricting means as a first reference position in the first shift position;
In the first shift position, power supply control means for permitting interruption of power supply to the shift range switching device;
When the shift position stored by the storage means is unknown, when the power supply is restarted after the power supply is cut off, the first reference position is reset by the first position setting means. A shift range switching device for an automatic transmission, comprising reference position resetting means for setting. The shift range switching device further includes second restriction means for restricting rotation of the actuator in a direction different from the predetermined direction at a second shift position of the plurality of shift positions,
The control means includes
After the first reference position is reset by said reference position re-setting means, the position of stopping the rotation of the actuator by the second regulating means as a second reference position in the second shift position Second position setting means for setting;
In order to calculate the movable range of the actuator based on the first reference position reset by the reference position resetting means and the second reference position set by the second position setting means The shift range switching device for an automatic transmission according to claim 1, further comprising: a movable range calculating means.   The control means is for determining a first target rotational position at the time of switching to the first shift position by the actuator based on the first reference position reset by the reference position resetting means. The shift range switching device for an automatic transmission according to claim 1, further comprising means. The shift range switching device further includes second restriction means for restricting rotation of the actuator in a direction different from the predetermined direction at a second shift position of the plurality of shift positions,
The control means includes
After I Ri said first reference position to the reference position re-setting means is reset, the position stopped by the second regulating means rotation of said actuator, second in the second shift position Second position setting means for setting as a reference position;
4. The shift of an automatic transmission according to claim 3, further comprising means for determining a second target rotational position at the time of switching to the second shift position by the actuator based on the second reference position. Range switching device. The shift range switching device further includes counting means for obtaining a count value according to the rotation amount of the actuator,
The position setting means includes means for setting the reference position of the actuator by detecting a state in which the minimum value or the maximum value of the count values acquired by the counting means does not change for a predetermined time. Item 5. The shift range switching device for an automatic transmission according to any one of Items 1 to 4. The shift range switching device further includes a detent spring that restricts rotation of the actuator in the predetermined direction and a direction different from the predetermined direction by a spring force generated by bending or extending of the rod-shaped member,
Said first regulating means includes means for restricting rotation of the predetermined direction of the actuator in a direction to shorten the detent spring, the shift range switching device of an automatic transmission according to claim 1 or 3. The shift range switching device further includes a detent spring that restricts rotation of the actuator in the predetermined direction and a direction different from the predetermined direction by a spring force generated by bending or extending of the rod-shaped member,
Said first regulating means includes means for restricting rotation of the predetermined direction of the actuator in a direction to shrink said detent spring,
5. The shift range of the automatic transmission according to claim 2, wherein the second restricting means includes means for restricting rotation of the actuator in a direction different from the predetermined direction in a direction in which the detent spring is pulled. Switching device. The first shift position is a P position where a parking mechanism is operated by driving the actuator,
The shift range switching device for an automatic transmission according to any one of claims 1 to 7, wherein the second shift position is a non-P position where the parking mechanism does not operate.

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