Motor control device

Abstract

A motor control device (40) controls the driving of a motor (10) in a motor drive system (1) having a motor (10) and a stop mechanism (20). The stop mechanism (20) includes a stop member (21) and an engaging member (26), wherein the stop member (21) rotates integrally with an output shaft (15) to which the rotation of the motor (10) is transmitted, and the engaging member (26) can move in valleys (211, 213) by the rotation of the motor (10) and position the output shaft (15) by stopping within a positioning range. The motor control device (40) includes a positioning determination unit (54) and an energization control unit (53). The positioning determination unit (54) determines whether the engaging member (26) can be stopped within a positioning range based on a control parameter other than a detection value of a motor rotation angle sensor that detects a motor rotation angle. The energization control unit (53) disconnects the energization to the motor (10) when it is determined that the engaging member (26) can be stopped within the positioning range.

Description

[0001] Cross-reference to related applications

[0002] This application is based on Japanese Patent Application No. 2019-217784 filed on December 2, 2019, and the contents thereof are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to a motor control device. Background Art

[0004] In the past, there is known a motor control device that uses a motor such as a switched reluctance motor as a driving source to drive a gear switching mechanism for switching the gear of an automatic transmission of a vehicle. For example, in Patent Document 1, a P gear side contact control and a NotP gear side contact control are performed to learn the amount of play in the rotation transmission system.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2004-023932 Summary of the invention

[0008] However, in the case of a brushed DC motor, even if there is no angle sensor inside the motor, the motor can be driven by switching the power on and off. The present disclosure aims to provide a motor control device that can appropriately locate the rotation position in a rotation transmission system without using a motor rotation angle sensor.

[0009] The motor control device disclosed in the present invention controls the driving of the motor in a gear shifting system having a motor and a stop mechanism. The stop mechanism has a stop member and a clamping member. The stop member is formed with a plurality of valleys, a mountain portion separating the valleys, and a wall portion provided at both ends of the arranged valleys, and rotates integrally with the output shaft to which the rotation of the motor is transmitted. The clamping member can move in the valley by the rotation of the motor, and stop within the required positioning range to position the output shaft.

[0010] The motor control device includes a positioning determination unit and a power-on control unit. The positioning determination unit determines whether the engaging component can be stopped within the positioning range based on control parameters other than the detection value of the motor rotation angle sensor that detects the motor rotation angle. The power-on control unit disconnects the power supply to the motor when it is determined that the engaging component can be stopped within the positioning range. Thus, the output shaft can be properly positioned without using the motor rotation angle sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The above-mentioned object and other objects, features and advantages of the present disclosure will become more apparent through the following detailed description with reference to the accompanying drawings.

[0012] Figure 1 It is a perspective view showing the shift-by-wire system according to the first embodiment.

[0013] Figure 2 It is a schematic diagram showing the configuration of a shift-by-wire system according to a first embodiment.

[0014] Figure 3 : is a circuit diagram showing a driving circuit unit according to the first embodiment.

[0015] Figure 4 It is a schematic diagram showing the stopper mechanism of the first embodiment.

[0016] Figure 5 It is a characteristic diagram showing the motor characteristics of the first embodiment.

[0017] Figure 6 This is a flowchart for explaining the motor control process according to the first embodiment.

[0018] Figure 7 This is a timing chart for explaining the motor control process according to the first embodiment.

[0019] Figure 8 This is a flowchart for explaining the motor control process according to the second embodiment.

[0020] Fig. 9 This is a timing chart for explaining the motor control process according to the second embodiment.

[0021] Fig.10 This is a flowchart for explaining the motor control process according to the third embodiment.

[0022] Fig.11 This is a timing chart for explaining the motor control process according to the third embodiment.

[0023] Fig.12 This is a timing chart for explaining the motor control process according to the fourth embodiment.

[0024] Fig.13 This is a timing chart for explaining the motor control process according to the fifth embodiment. DETAILED DESCRIPTION

[0025] (First Embodiment)

[0026] Hereinafter, the motor control device of the present disclosure will be described based on the drawings. In the following, in a plurality of embodiments, substantially the same configurations are denoted by the same reference numerals and description thereof will be omitted. Figure 1 to Figure 7 A first embodiment is shown in FIG. Figure 1 to Figure 3As shown, a shift-by-wire system 1 as a motor drive system includes a motor 10 as an actuator, a shift position switching mechanism 20 , a parking lock mechanism 30 , and a shift position control device 40 as a motor control device.

[0027] The motor 10 rotates by being supplied with electric power from a battery 90 as a power source mounted on a vehicle (not shown), and functions as a driving source for the shift position switching mechanism 20. The motor 10 of the present embodiment is a brushed DC motor and has a motor winding 11.

[0028] The speed reducer 14 is provided on the motor shaft 105 of the motor 10 (see Figure 4 The rotation of the motor 10 is decelerated and output to the output shaft 15. Thus, the rotation of the motor 10 is transmitted to the shift position switching mechanism 20. The output shaft 15 is provided with an output shaft sensor 16 for detecting the angle of the output shaft 15. The output shaft sensor 16 is, for example, a potentiometer.

[0029] like Figure 1 As shown, the shift range switching mechanism 20 includes a detent plate 21 , a detent spring 25 and a detent roller 26 as urging members, and transmits the rotational driving force output from the speed reducer 14 to a manual valve 28 and a parking lock mechanism 30 .

[0030] The stop plate 21 is fixed to the output shaft 15 and driven by the motor 10. A pin 24 protruding in parallel with the output shaft 15 is provided on the stop plate 21. The pin 24 is connected to the manual valve 28. The stop plate 21 is driven by the motor 10, so that the manual valve 28 reciprocates in the axial direction. That is, the shift position switching mechanism 20 converts the rotational motion of the motor 10 into a linear motion and transmits it to the manual valve 28. The manual valve 28 is provided on the valve body 29. The manual valve 28 reciprocates in the axial direction, so that the hydraulic supply path to the hydraulic clutch not shown in the figure is switched, and the engagement state of the hydraulic clutch is switched, thereby changing the shift position.

[0031] The stopper plate 21 is provided with two valleys 211 and 212 on the stopper spring 25 side (see Figure 4 In the present embodiment, the valley portion 211 corresponds to the P position, and the valley portion 212 corresponds to the NotP position which is a position other than the P position.

[0032] Figure 4 Schematically shows the relationship between the motor shaft 105, which is the rotating shaft of the motor 10, the output shaft 15, and the stop plate 21. Figure 4As shown, a mountain portion 215 is formed between a valley portion 211 corresponding to the P position and a valley portion 212 corresponding to the NotP position which is a position other than the P position on the stop plate 21. In addition, a wall portion 213 for limiting the movement of the stop roller 26 is formed on the opposite side of the mountain portion 215 of the valley portion 211, and a wall portion 214 for limiting the movement of the stop roller 26 is formed on the opposite side of the mountain portion 215 of the valley portion 212. In the figure, the valley portion 211 is appropriately described as "P valley", the valley portion 212 is described as "NotP valley", the wall portion 213 is described as "P wall", the wall portion 214 is described as "NotP wall", and the mountain portion 215 is described as "mountain".

[0033] A clearance is formed between the motor shaft 105 and the output shaft 15. Figure 4 In the embodiment, the reducer 14 and the output shaft 15 are integrated, and a "play" is formed between the motor shaft 105 and the reducer 14, but the motor shaft 105 and the reducer 14 may be integrated, and a "play" is formed between the reducer 14 and the output shaft 15. "Play" can be understood as the sum of play, looseness, etc. existing between the motor shaft 105 and the output shaft 15, and is appropriately referred to as "looseness G" hereinafter.

[0034] exist Figure 4 In FIG. 1 , the rotation direction of the motor 10 is set to the left-right direction of the paper, and the stop roller 26 is shown to move between the valleys 211 and 212 as the output shaft 15 rotates. In fact, the stop plate 21 rotates so that the stop roller 26 moves between the valleys 211 and 212, but in FIG. Figure 4 In the figure, for the sake of explanation, the stopper roller 26 is shown moving together with the output shaft 15. In order to avoid complication, reference numerals are omitted as appropriate.

[0035] return Figure 1 The stop spring 25 is a plate-shaped component that can be elastically deformed, and a stop roller 26 is provided at the front end. The stop spring 25 applies force to the stop roller 26 toward the rotation center side of the stop plate 21, that is, the side that is engaged with the valleys 211 and 212. If a rotational force greater than a specified value is applied to the stop plate 21, the stop spring 25 is elastically deformed, and the stop roller 26 moves between the valleys 211 and 212. The stop roller 26 is embedded in one of the valleys 211 and 212, so that the swing of the stop plate 21 is restricted, the axial position of the manual valve 28 and the state of the parking lock mechanism 30 are determined, and the shift position of the automatic transmission 5 is fixed. The stop roller 26 is embedded in the valley 211 when the shift position is the P position, and is embedded in the valley 212 when it is the NotP position.

[0036] The parking lock mechanism 30 includes a parking rod 31, a cone 32, a parking lock pawl 33, a shaft 34, and a parking gear 35. The parking rod 31 is formed in a substantially L-shape, and one end 311 is fixed to the stopper plate 21. The cone 32 is provided on the other end 312 of the parking rod 31. The cone 32 is formed so that the diameter decreases as it goes toward the other end 312.

[0037] The parking lock pawl 33 is in contact with the conical surface of the cone 32 and is configured to be able to swing around the shaft 34. A convex portion 331 that can mesh with the parking gear 35 is provided on the parking gear 35 side of the parking lock pawl 33. If the stop plate 21 rotates in the reverse direction and the cone 32 moves in the P direction, the parking lock pawl 33 is pushed up and the convex portion 331 meshes with the parking gear 35. On the other hand, if the stop plate 21 rotates in the forward direction and the cone 32 moves in the NotP direction, the meshing of the convex portion 331 with the parking gear 35 is released.

[0038] The parking gear 35 is provided on the axle (not shown) and is arranged to be able to mesh with the convex portion 331 of the parking lock pawl 33. When the parking gear 35 meshes with the convex portion 331, the rotation of the axle is restricted. When the shift position is the notP position, the parking gear 35 is not locked by the parking lock pawl 33, and the rotation of the axle is not hindered by the parking lock mechanism 30. In addition, when the shift position is the P position, the parking gear 35 is locked by the parking lock pawl 33, and the rotation of the axle is restricted.

[0039] like Figure 2 as well as Figure 3 As shown in FIG. 1 , the shift position control device 40 includes a drive circuit unit 41 and a control unit 50. In the figure, the control unit 50 is described as “ECU”. Figure 3 As shown, the drive circuit unit 41 has four switching elements 411 to 414, forming an H-bridge circuit. The switching elements 411 to 414 of the present embodiment are MOSFETs, but may also be IGBTs or the like. When the motor 10 is rotated forward, the switching elements 411 and 414 are turned on, and when the motor 10 is reversed, the switching elements 412 and 413 are turned on. The motor 10 of the present embodiment is a brushed motor, and therefore the detection value of the rotation angle sensor is not used, and the drive motor 10 can be controlled by turning the switching elements 411 to 414 on and off. Therefore, the rotation angle sensor inside the motor 10 can be omitted.

[0040] The current sensor 45 detects the motor current Im which is the current of the motor winding 11. Figure 3 In the figure, the current sensor 45 is arranged on the low potential side of the driving circuit part 41, but can also be arranged on the high potential side of the driving circuit part 41, between the connection point of the switching elements 411 and 412 and the motor winding 11, or between the connection point of the switching elements 413 and 414 and the motor winding 11.

[0041] like Figure 2 As shown, the control unit 50 is mainly composed of a microcomputer, etc., and has a CPU, ROM, RAM, I / O, and a bus connecting these components, all of which are not shown. Each process in the control unit 50 can be a software process implemented by the CPU executing a program pre-stored in a physical memory device such as a ROM (i.e., a readable non-temporary tangible recording medium), or a hardware process based on a dedicated electronic circuit.

[0042] The control unit 50 includes a current acquisition unit 51 , an output shaft position acquisition unit 52 , an energization control unit 53 , a positioning determination unit 54 , etc. The current acquisition unit 51 acquires the motor current Im based on the detection value of the current sensor 45 .

[0043] The output shaft position acquisition unit 52 detects the output shaft angle θs, which is the rotation position of the output shaft 15, based on the detection value of the output shaft sensor 16. In the present embodiment, the rotation of the motor 10 is transmitted to the output shaft 15 via the speed reducer 14. There is a "play" between the output shaft 15 and the motor shaft 105. Therefore, although the motor angle θm and the output shaft angle θs can be roughly converted according to the gear ratio of the speed reducer 14, due to the influence of the looseness G, the converted value of the output shaft angle θs is not necessarily consistent with the motor angle θm of the actual rotor position.

[0044] The energization control unit 53 controls the driving of the motor 10 by controlling the on / off operation of the switching elements 411 to 414 and controlling the energization of the motor winding 11. In the present embodiment, the detection value of a rotation angle sensor for detecting the rotor position such as an encoder is not used in the on / off control of the switching elements 411 to 414. The positioning determination unit 54 determines whether the stop roller 26 can be stopped within the positioning range that satisfies the shift position switching.

[0045] like Figure 4 As shown, when the shift position is switched from the P position to the NotP position, the motor 10 is rotated forward, as shown in FIG. Figure 4 As shown by the solid arrow in , the stop roller 26 is moved from the valley 211 to the valley 212 via the mountain 215. At this time, the motor 10 is controlled so that the stop roller 26 stops within the NotP gear range.

[0046] In addition, when the shift position is switched from the NotP position to the P position, the motor 10 is reversed to move the stop roller 26 from the valley 212 to the valley 211 via the hill 215. At this time, the motor 10 is controlled so that the stop roller 26 stops within the parking lock range. That is, when switching from the P position to the NotP position, the NotP position range corresponds to the "positioning range", and when switching from the NotP position to the P position, the parking lock range corresponds to the "positioning range". The following description will focus on the switching from the P position to the NotP position.

[0047] However, when a switched reluctance motor is used as a driving source of the shift-by-wire system 1, for example, the rotor is rotated by switching the energized phase based on the detection value of a motor rotation angle sensor such as an encoder. In addition, abutment control is performed to make the stop roller 26 abut against the wall portions 213 and 214, and the amount of play between the motor shaft 105 and the output shaft 15 is learned based on the encoder count value. Then, using the learned amount of play, the energized phase is switched according to the detection value of the motor rotation angle sensor, so that positioning accuracy is satisfied.

[0048] On the other hand, in a brushed DC motor, even without switching the energized phase, the rotor can be rotated by switching the energization on and off. That is, in the case of a brushed DC motor, there is no need to provide a rotation angle sensor inside. In addition, when a motor 10 without a rotation angle sensor is used as a driving source of the shift-by-wire system 1, the amount of play cannot be learned.

[0049] Therefore, in this embodiment, the rotation angle sensor inside the motor 10 is not used, but the stop roller 26 is brought into contact with the wall portions 213 and 214 for the purpose of shifting the gear, thereby determining that the stop roller 26 is within the positioning range. Figure 5 As shown, if the stop roller 26 abuts against the wall portions 213 and 214, the rotation speed N decreases, the torque T increases, and the current I increases. Therefore, in the present embodiment, when the motor current Im is equal to or greater than the abutment determination value Ith for a period of time equal to or greater than the abutment determination time Xth1, the stop roller 26 abuts against the wall portions 213 and 214, and it is determined that the motor 10 is within the positioning range, and the power supply to the motor 10 is turned off.

[0050] based on Figure 6 The motor control process is described in the flowchart of FIG. This process is executed by the control unit 50 at a predetermined cycle. Hereinafter, the "step" of step S101 is omitted and is only recorded as the symbol "S". The other steps are the same.

[0051] In S101, the control unit 50 determines whether there is a shift position switching request. If it is determined that there is no shift position switching request (S101: NO), the process proceeds to S107 and remains on standby. If it is determined that there is a shift position switching request (S101: YES), the process proceeds to S102.

[0052] In S102, the control unit 50 determines whether the input voltage V is greater than the voltage judgment value Vth. In the present embodiment, the input voltage V is set to the battery voltage. When it is determined that the input voltage V is less than the voltage judgment value Vth (S102: NO), the process moves to S107 and continues to wait. When it is determined that the input voltage V is greater than the voltage judgment value Vth (S102: YES), the process moves to S103 and the power to the motor 10 is turned on. Here, based on the detection value of the current sensor 45, the on-off operation of the switching elements 411 to 414 is controlled by current feedback control so that the motor current Im is constant. In addition, the power to the motor 10 can also be turned on at a certain duty cycle.

[0053] In S104, the positioning determination unit 54 determines whether the motor current Im is greater than or equal to the contact determination value Ith. The contact determination value Ith is set to a value sufficiently larger than the current flowing when the stop roller 26 moves between the valleys 211 and 212. When it is determined that the motor current Im is less than the contact determination value Ith (S104: NO), the process returns to S103 and continues to energize the motor 10. When it is determined that the motor current Im is greater than or equal to the contact determination value Ith (S104: YES), the process moves to S105.

[0054] In S105, the positioning determination unit 54 determines whether the elapsed time X from when the motor current Im becomes greater than the abutment determination value Ith is greater than the abutment determination time Xth1. The abutment determination time Xth1 is set based on the time that can be determined as the abutment of the stop roller 26 against the wall portions 213, 214 in order to prevent erroneous determinations caused by noise, etc. When it is determined that the elapsed time X is less than the abutment determination time Xth1 (S105: NO), return to S103 and continue to energize the motor 10. When it is determined that the elapsed time X1 is greater than the abutment determination time Xth1 (S105: YES), move to S106. In S106, the power control unit 53 disconnects the power to the motor 10. In S107, the control unit 50 puts the motor drive mode into standby mode.

[0055] based on Figure 7 The motor control process of this embodiment is described in detail with reference to the timing chart. Figure 7 The upper part shows the Figure 4The schematic diagram of the behavior of the corresponding stop roller 26 shows a timing diagram in the lower half. In the timing diagram, the common time axis is set as the horizontal axis, and the motor current Im, the motor drive mode and the torque are shown from the top. In order to avoid complication, the reference numerals in the schematic diagram are appropriately omitted. The timing diagram of the embodiment described later is also the same.

[0056] At time x10 , when a shift range switching request is issued and the motor 10 is energized, the stopper roller 26 moves from the valley portion 211 to the valley portion 212 side by driving the motor 10 .

[0057] At time x11, if the stop roller 26 abuts against the wall 214, the motor current Im and the motor torque are greater than before the abutment. At time x12 after the motor current Im becomes equal to or greater than the abutment determination value Ith and the abutment determination time Xth1 has passed, the power supply to the motor 10 is turned off. In addition, in the present embodiment, the power supply is turned off without performing a stop control such as a fixed phase power supply control.

[0058] When the power supply to the motor 10 is turned off while the stop roller 26 is in contact with the wall 214, even if the stop roller 26 leaves the wall 214 due to the spring force of the stop spring 25 and the restoring force of the motor 10, it will not go beyond the valley 212 and return to the side of the hill 215. Therefore, without using a rotation angle sensor inside the motor 10, the stop roller 26 can be reliably stopped within the NotP range.

[0059] As described above, the shift position control device 40 of the present embodiment controls the driving of the motor 10 in the shift-by-wire system 1. The shift-by-wire system 1 includes the motor 10 and the shift position switching mechanism 20. The shift position switching mechanism 20 includes the stopper plate 21 and the stopper roller 26. The stopper plate 21 is formed with a plurality of valleys 211 and 212, a mountain portion 215 separating the valleys 211 and 212, and walls 213 and 214 provided at both ends of the valleys 211 and 212 arranged in a row, and rotates integrally with the output shaft 15 to which the rotation of the motor 10 is transmitted. The stopper roller 26 can move in the valleys 211 and 212 by the rotation of the motor 10, and stop in a positioning range corresponding to the requested shift position, thereby positioning the output shaft 15.

[0060] The shift position control device 40 includes a positioning determination unit 54 and a power supply control unit 53. The positioning determination unit 54 determines whether the stop roller 26 can be stopped within the positioning range based on control parameters other than the detection value of the motor rotation angle sensor that detects the motor rotation angle. When the power supply control unit 53 determines that the stop roller 26 can be stopped within the positioning range, it turns off the power supply to the motor 10. Thus, even if a motor rotation angle sensor such as an encoder is not used, the output shaft 15 can be positioned and the shift position can be appropriately switched.

[0061] In the present embodiment, the motor current Im supplied to the motor 10 is used as a control parameter. When the motor current Im is greater than or equal to the contact determination value Ith for the contact determination time Xth1, the positioning determination unit 54 determines that the stopper roller 26 is in contact with the wall portions 213 and 214 adjacent to the valley portions 211 and 212 corresponding to the requested shift position, and the stopper roller 26 can be stopped within the positioning range. By causing the stopper roller 26 to contact the wall portions 213 and 214, the positioning can be reliably satisfied.

[0062] (Second Embodiment)

[0063] exist Figure 8 as well as Fig. 9 A second embodiment is shown in FIG. In the following embodiment, the motor control process is different from the above-mentioned embodiment, so the description will focus on this point. Figure 8 The motor control process of this embodiment is described in the flowchart of FIG. Figure 6 The processing of S101 to S103 is the same.

[0064] In S204, the control unit 50 determines whether the stop roller 26 has reached the current reduction position. The current reduction position is between the valley 212 and the wall 214 when switching from the P position to the NotP position, and is between the valley 211 and the wall 213 when switching from the NotP position to the P position. In terms of responsiveness, the current reduction position is preferably set as close to the wall 213, 214 as possible.

[0065] In the present embodiment, when the elapsed time from the start of energization, i.e., the motor drive time Xd, is greater than the current reduction position arrival determination time Xth2, it is determined that the stop roller 26 has reached the current reduction position. In addition, for example, it is also possible to determine whether the current reduction position has been reached based on the detection value of the output shaft sensor 16. In addition, it is also possible to determine based on the energization amount A which is the time integral value of the motor current Im. If the motor current Im is considered constant, the energization amount A can be calculated as the product of the motor current Im and the motor drive time Xd (refer to formula (1)).

[0066] A=Im×Xd···(1)

[0067] If it is determined that the stopper roller 26 has not reached the current reduction position (S204: NO), the process returns to S203 to continue energizing the motor 10. If it is determined that the stopper roller 26 has reached the current reduction position (S204: YES), the process proceeds to S205.

[0068] In S205, the control unit 50 reduces the motor current Im. The motor current Im after reduction is set to an arbitrary value smaller than that before reduction, to a degree that the stop roller 26 can be driven to the wall portions 213 and 214. The processing of S206 to S209 is the same as the processing of S104 to S107. If the determination in S206 or S207 is negative, the power is continued in the state of reducing the motor current Im.

[0069] based on Fig. 9 The motor control process of this embodiment is described in detail with reference to the timing chart. Figure 7 The processing at time x10 in is the same as that at time x21. If the stop roller 26 reaches the current reduction position at time x22, the motor current Im is reduced. Figure 7 The processing after time x21 is the same.

[0070] In this embodiment, the motor current Im is reduced before the stop roller 26 reaches the wall 214, so that the motor current Im and the torque can be reduced within the contact determination time Xth1 as shown by the arrows Yi and Yt. Alternatively, the current reduction position may be the position where the stop roller 26 contacts the wall 214, and the motor current Im may be reduced after the stop roller 26 contacts the wall 214.

[0071] In the present embodiment, when it is determined that the stop roller 26 can stop within the positioning range by abutting against the wall portions 213 and 214 adjacent to the valley portions 211 and 212 corresponding to the requested shift position, the power supply control unit 53 makes the motor current Im supplied to the motor 10 smaller than before reaching the current reduction position when it is determined that the stop roller 26 has reached the front side of the abutment against the wall portions 213 and 214, that is, the current reduction position. Thus, the power supply amount during the abutment determination time Xth1 can be suppressed. In addition, the impact when the stop roller 26 abuts against the wall portions 213 and 214 can be suppressed. In addition, the same effect as the above-mentioned embodiment is achieved.

[0072] (Third Embodiment)

[0073] based on Fig.10 as well as Fig.11 A third embodiment will be described. Fig.10 The motor control process of this embodiment is described in the flowchart of FIG. Figure 6 The processing of S101 to S103 is the same.

[0074] In S304, it is determined whether the stop roller 26 has reached the energized disconnected position based on the detection value of the output shaft sensor 16. The energized disconnected position is arbitrarily set according to the position at which the stop roller 26 can stop within the positioning range corresponding to the requested shift position. Fig.11 If it is determined that the power-off position has not been reached (S304: NO), the process returns to S303 to continue the power supply to the motor 10. If it is determined that the power-off position has been reached (S304: YES), the process moves to S305. The processing of S305 and S306 is the same as Figure 6 The processing of S106 and S107 is the same.

[0075] based on Fig.11 The motor control process of this embodiment is described in detail with reference to the timing chart. Fig.11 In FIG. 1 , the output shaft angle θs is shown instead of the motor current Im in the above embodiment. Here, the output shaft angle when the stop roller 26 is located at the top of the mountain portion 215 is θs1, the output shaft angle when it is located at the bottom of the valley portion 212 is θs2, and the output shaft angle when it abuts against the wall portion 214 is θs3.

[0076] The processing of time x30 and Figure 7 The processing at time x10 in is the same. At time x31, if the output shaft angle θs exceeds the angle θs1, it is considered that the stop roller 26 has passed over the hill 215, and the power supply to the motor 10 is disconnected. If the stop roller 26 passes over the hill 215, the stop roller 26 falls to the valley 212 due to the force of the stop spring 25, and can be positioned within the NotP gear range.

[0077] That is, at time x31, although the stop roller 26 has not reached the NotP range, if the power is turned off, the stop roller 26 is in a position that can be moved to the NotP range. That is, the timing of turning off the power does not necessarily require the stop roller 26 to be within the positioning range. In other words, if the stop roller 26 exceeds the mountain 215, it can also be determined that "the engaging member can be stopped within the positioning range."

[0078] Alternatively, at time x32, when the output shaft angle θs becomes angle θs2, the stop roller 26 is regarded as being located at the valley 212, and the power supply to the motor 10 is turned off. Alternatively, at time x33, when the output shaft angle θs becomes angle θs3, the stop roller 26 is regarded as being in contact with the wall 214, and the power supply to the motor 10 is turned off. At this time, as in the second embodiment, the motor current Im may be reduced before the stop roller 26 is in contact with the wall 214.

[0079] exist Fig.11In the figure, regarding the motor drive mode and torque, the position of the stop roller 26 is shown by a solid line when it is powered on and off at the mountain portion 215, by a dotted line when it is powered on and off at the valley portion 212, and by a dashed line when it is powered on and off at the wall portion 214. In addition, the output shaft angle that powers off the motor 10 can be set to any value that can stop the stop roller 26 within the NotP range, for example, when the stop roller 26 reaches the NotP position or reaches the current reduction position of the second embodiment. The same applies to the embodiments described later.

[0080] In this embodiment, the positioning determination unit 54 determines whether the stop roller 26 can be stopped within the positioning range based on the output shaft angle θs, which is the rotation angle of the output shaft 15. Thus, it is possible to appropriately determine whether the stop roller 26 can be stopped within the positioning range. In addition, the same effects as those of the above embodiment are achieved.

[0081] (Fourth Embodiment)

[0082] based on Fig.12 The fourth embodiment will be described. The determination of reaching the energization OFF position in S304 of the motor control process of this embodiment is different from that of the third embodiment in that the determination is made based on the motor drive time Xd instead of the detection value of the output shaft sensor 16. Fig.12 The motor control process of this embodiment is described in detail with reference to the timing chart. Fig.12 In, replace Fig.11 Here, the time required for the stop roller 26 to reach the mountain portion 215 is set as time Xd1, the time required to reach the bottom of the valley portion 212 is set as time Xd2, and the time required to reach the wall portion 214 is set as time Xd3.

[0083] The processing of time x40 and Figure 7 The processing of moment x10 in is the same. At moment x41, if the motor drive time Xd exceeds the time Xd1, it is regarded that the stop roller 26 exceeds the hill 215, and the power to the motor 10 is disconnected. Alternatively, at moment x42, when the motor drive time Xd is time Xd2, it is regarded that the stop roller 26 is located in the valley 212, and the power to the motor 10 is disconnected. Alternatively, at moment x43, when the motor drive time Xd becomes time Xd3, it is regarded that the stop roller 26 abuts against the wall 214, and the power to the motor 10 is disconnected. In addition, the times Xd1, Xd2, and Xd3 can also be variable according to the input voltage V and the temperature. Such a configuration also has the same effect as the above-mentioned embodiment.

[0084] (Fifth Embodiment)

[0085] based on Fig.13The fifth embodiment will be described. The determination of reaching the energized disconnected position in S304 of the motor control process of this embodiment is different from that of the third embodiment in that the determination is made based on the energized amount A (see equation (1)) instead of the detection value of the output shaft sensor 16. Fig.13 In, replace Fig.11 The output shaft angle θs shows the motor current Im. In this embodiment, it is assumed that the power to the motor 10 is disconnected when the stop roller 26 reaches the bottom of the valley 212 for explanation. In addition, the timing of disconnecting the power to the motor 10 is the same as that in the above-mentioned embodiment, and can also be any timing that can stop the stop roller 26 within the NotP gear range.

[0086] The processing of time x50 and Figure 7 At time x52, if the energization amount A reaches the energization amount determination value Ath, the stopper roller 26 is regarded as being located at the bottom of the valley 212, and the energization to the motor 10 is turned off. The energization amount determination value Ath may also be variable according to the input voltage V and the temperature.

[0087] In addition, as shown by the single-dot chain line, when a relatively larger current than the current shown by the solid line flows, the stop roller 26 reaches the bottom of the valley portion 212 in a relatively short time. Fig.13 In the process, when the energization amount A reaches the energization amount determination value Ath at time x51, the energization to the motor 10 is turned off at time x51, and the process shifts to the standby mode.

[0088] In this embodiment, the positioning determination unit 54 determines whether the stop roller 26 can be stopped within the positioning range based on the amount of current flow as the integral value of the motor current Im. Thus, it is possible to appropriately determine whether the stop roller 26 can be stopped within the positioning range. In addition, the same effects as those of the above embodiment are achieved.

[0089] In the implementation mode, the shift-by-wire system 1 corresponds to the "motor drive system", the shift position switching mechanism 20 corresponds to the "stop mechanism", the stop plate 21 corresponds to the "stop component", the stop roller 26 corresponds to the "engagement component", and the shift position control device 40 corresponds to the "motor control device".

[0090] (Other embodiments)

[0091] In the above embodiment, the motor is a brushed motor. In other embodiments, the motor may be a motor other than a brushed motor, such as a switched reluctance motor or a brushless motor. In addition, in the above embodiment, the motor is not provided with a motor rotation angle sensor. In other embodiments, the motor may also be provided with a motor rotation angle sensor. In this case, for example, when an abnormality occurs in the motor rotation angle sensor, the positioning control of the above embodiment may also be performed.

[0092] In the above embodiment, two valleys are provided on the stop plate. In other embodiments, the number of valleys is not limited to two, and may be three or more. In addition, the gear shift position switching mechanism, the parking lock mechanism, etc. may also be different from the above embodiment. In addition, in the above embodiment, the motor control device is applied to the gear shift position switching system. In other embodiments, the motor control device may also be applied to a vehicle-mounted system other than the gear shift position switching system, or a motor drive system other than the vehicle-mounted system.

[0093] In the above embodiment, a speed reducer is provided between the motor shaft and the output shaft. The details of the speed reducer are not mentioned in the above embodiment, and it may be any structure such as a speed reducer using a cycloid gear, a planetary gear, a spur gear that transmits torque from a speed reduction mechanism substantially coaxial with the motor shaft to the drive shaft, or a speed reducer using a combination of these. In addition, in other embodiments, the speed reducer between the motor shaft and the output shaft may be omitted, and a mechanism other than a speed reducer may be provided.

[0094] The control unit and method thereof described in the present disclosure may also be implemented by a special-purpose computer provided by a processor and a memory programmed in a manner to execute one or more functions embodied by a computer program. Alternatively, the control unit and method thereof described in the present disclosure may also be implemented by a special-purpose computer provided by a processor composed of one or more special-purpose hardware logic circuits. Alternatively, the control unit and method thereof described in the present disclosure may also be implemented by one or more special-purpose computers composed of a combination of a processor and a memory programmed in a manner to execute one or more functions and a processor composed of one or more hardware logic circuits. In addition, the computer program may also be stored in a computer-readable non-transitional tangible recording medium as an instruction executed by a computer. As described above, the present disclosure is not limited in any way by the above-mentioned embodiments and can be implemented in various ways without departing from its main purpose.

[0095] The present disclosure is described in accordance with the embodiments. However, the present disclosure is not limited to the embodiments and structures. The present disclosure also includes various modifications and modifications within the equivalent range. In addition, various combinations and methods, and further other combinations and methods including only one element, more than one element, or less than one element among them, also fall within the scope and thought of the present disclosure.

Claims

1. A motor control device for controlling the driving of a motor in a motor driving system, wherein the motor driving system comprises: the motor; as well as The stop mechanism comprises a stop member and a locking member, wherein the stop member is formed with a plurality of valleys, a mountain portion separating the valleys, and a wall portion provided at both ends of the arranged valleys, and rotates integrally with an output shaft to which the rotation of the motor is transmitted, and the locking member can move in the valleys by the rotation of the motor, and positions the output shaft by stopping within a positioning range, The motor control device is characterized by comprising: a positioning determination unit that determines whether the engaging member can be stopped within the positioning range based on a control parameter other than a detection value of a motor rotation angle sensor that detects a motor rotation angle; as well as The power supply control unit turns off the power supply to the motor when it is determined that the engagement member can be stopped within the positioning range. The control parameter is the motor current supplied to the motor, When it is determined that the engaging member can be stopped within the positioning range due to the engaging member abutting against the wall portion, When the current control unit determines that the engagement member has reached a current reduction position on the front side of the engagement member abutting against the wall, the motor current is reduced to a value lower than the current before the motor current reaches the current reduction position. The positioning determination unit determines that the engaging member is in contact with the wall and the engaging member can stop within the positioning range when the motor current increases after the motor current decreases and the motor current continues to be equal to or greater than the contact determination value for a contact determination time.

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