Abnormality monitoring device

Abstract

An abnormality monitoring device (401, 402) includes a drive circuit portion (41), a current detection portion (45-47), a current cutoff portion (42), a first control portion (51), and a second control portion (52). The drive circuit portion (41) switches energization to a motor winding (11). The current detection portion (45-47) detects a motor current that flows through the motor winding (22). The current cutoff portion (42) can cut off the motor current. The first control portion (51) has an energization control portion (53) that controls energization to the motor winding (11) and an energization state notification portion (54) that outputs an energization state signal corresponding to an energization instruction state. The second control portion (60, 61) is provided separately from the first control portion (51) and has an abnormality monitoring portion (65) that monitors an abnormality based on a detection value of the current detection portion (45-47) and the energization state signal and performs a fail-safe treatment corresponding to a monitoring result.

Description

[0001] Cross-reference of related applications

[0002] This application is based on Japanese Patent Application No. 2020-027044, filed on February 20, 2020, the contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to anomaly monitoring devices. Background Technology

[0004] Previously, a gear shifting device was known that controlled a motor to switch gears based on a gear shifting request from the driver. For example, in Patent Document 1, a fault safety procedure was performed when the target gear did not match the actual gear.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2019-94998 Summary of the Invention

[0008] For example, in Patent Document 1, where the drive control unit and the anomaly monitoring unit are composed of the same microcomputer, anomaly detection cannot be performed in the event of a microcomputer malfunction. The purpose of this disclosure is to provide an anomaly monitoring device capable of implementing appropriate fail-safe measures when an anomaly occurs.

[0009] The abnormality monitoring device disclosed herein is an abnormality monitoring device for monitoring energization abnormalities of a motor having motor windings, and includes a drive circuit section, a current detection section, a first control section, and a second control section. The drive circuit section switches the energization of the motor windings. The current detection section detects the current flowing through the motor windings, i.e., the motor current. The current cutoff section can cut off the motor current.

[0010] The first control unit includes an energization control unit that controls the energization of the motor windings and an energization status notification unit that outputs an energization status signal corresponding to the energization command status. The second control unit is separately located from the first control unit and includes an anomaly monitoring unit that monitors for anomalies based on the detection value from the current detection unit and the energization status signal, and performs fault-safe procedures corresponding to the monitoring results. By utilizing the second control unit, which is separately located from the first control unit, for anomaly monitoring, appropriate fault-safe procedures can be performed even if an anomaly occurs in the first control unit. Attached Figure Description

[0011] The above-mentioned and other objects, features, and advantages of the present invention will become more apparent from the accompanying drawings and from the following detailed description. The drawings are as follows:

[0012] Figure 1 This is a perspective view showing the shift-by-wire system of the first embodiment;

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

[0014] Figure 3 This is a circuit diagram showing the gear shift control device of the first embodiment;

[0015] Figure 4 This is a flowchart illustrating the anomaly monitoring process of the first embodiment;

[0016] Figure 5 This is a circuit diagram showing the gear shift control device of the second embodiment;

[0017] Figure 6 This is an explanatory diagram illustrating the on / off control of the signal switching unit in the second embodiment;

[0018] Figure 7 This is a flowchart illustrating the anomaly monitoring process of the second embodiment. Detailed Implementation

[0019] The anomaly monitoring device will now be described with reference to the accompanying drawings. In the following embodiments, substantially identical structures will be labeled with the same reference numerals and descriptions will be omitted.

[0020] <First Implementation Method>

[0021] Figures 1-4 The first embodiment is shown in the figure. For example... Figures 1-3 As shown, the drive-by-wire shifting system 1, which is a motor drive system, includes a motor 10 as an actuator, a shifting gear switching mechanism 20, a parking locking mechanism 30, and a shifting gear control device 401 as an abnormality monitoring and control device.

[0022] The motor 10 is powered by a battery 90 (not shown) that serves as a power source, and functions as a drive source for the gear shifting mechanism 20. In this embodiment, the motor 10 is a brushed DC motor with motor windings 11.

[0023] The reducer 14 is located between the motor shaft and the output shaft 15 of the motor 10, reducing the rotation speed of the motor 10 and outputting it to the output shaft 15. Thus, the rotation of the motor 10 is transmitted to the gear shifting mechanism 20. An output shaft sensor 16 is provided on the output shaft 15 to detect the angle of the output shaft 15. The output shaft sensor 16 is, for example, a potentiometer.

[0024] like Figure 1As shown, the gear shifting mechanism 20 has a stop plate 21, a stop spring 25 as a force-applying component, and a stop roller 26, etc., which transmit the rotational driving force output from the reducer 14 to the manual valve 28 and the parking locking mechanism 30.

[0025] A stop plate 21 is fixed to the output shaft 15 and driven by the motor 10. A pin 24 protrudes parallel to the output shaft 15 from the stop plate 21. The pin 24 is connected to a manual valve 28. By driving the stop plate 21 with the motor 10, the manual valve 28 reciprocates axially. That is, the gear shifting mechanism 20 converts the rotational motion of the motor 10 into linear motion and transmits it to the manual valve 28. The manual valve 28 is located on the valve body 29. By reciprocating axially with the manual valve 28, the hydraulic supply path to a hydraulic clutch (not shown) is switched, changing the engagement state of the hydraulic clutch, thereby changing the gear position.

[0026] Two valleys 211 and 212 are provided on the stop spring 25 side of the stop plate 21. In this embodiment, valley 211 corresponds to the P gear, and valley 212 corresponds to gears other than P gear, i.e., non-P gear.

[0027] The stop spring 25 is a plate-shaped component capable of elastic deformation, with a stop roller 26 at its front end. The stop spring 25 applies force to the stop roller 26 towards the rotation center side of the stop plate 21, i.e., the side that engages with the valleys 211 and 212. If a specified or greater rotational force is applied to the stop plate 21, the stop spring 25 elastically deforms, and the stop roller 26 moves between the valleys 211 and 212. By engaging the stop roller 26 with one of the valleys 211 and 212, the swing of the stop plate 21 is limited, the axial position of the manual valve 28 and the state of the parking lock mechanism 30 are determined, and the shift gear of the automatic transmission 5 is fixed. The stop roller 26 engages with valley 211 when the shift gear is P (Park) and with valley 212 when the shift gear is not P.

[0028] The parking locking mechanism 30 includes a parking lever 31, a cone 32, a parking locking lever 33, a shaft 34, and a parking gear 35. The parking lever 31 is generally L-shaped, with one end 311 fixed to the stop plate 21. A cone 32 is provided at the other end 312 of the parking lever 31. The cone 32 is formed such that its radial dimension decreases as it moves towards the other end 312.

[0029] The parking lock lever 33 abuts against the conical surface of the cone 32. A protrusion 331, capable of engaging with the parking gear 35, is provided on the side of the parking lock lever 33, which is configured to swing around the shaft 34. If the stop plate 21 rotates in the opposite direction, causing the cone 32 to move in the P direction, the parking lock lever 33 is pushed upwards, and the protrusion 331 engages with the parking gear 35. Conversely, if the stop plate 21 rotates in the forward direction, causing the cone 32 to move in a direction other than P, the engagement of the protrusion 331 with the parking gear 35 is disengaged.

[0030] A parking gear 35 is mounted on an axle (not shown) and is configured to engage with a protrusion 331 of the parking lock lever 33. When the parking gear 35 engages with the protrusion 331, rotation of the axle is restricted. When the gear position is not P (Park), the parking gear 35 is not locked by the parking lock lever 33, and rotation of the axle is not hindered by the parking lock mechanism 30. Furthermore, when the gear position is P (Park), the parking gear 35 is locked by the parking lock lever 33, and rotation of the axle is restricted.

[0031] like Figure 2 and Figure 3 As shown, the gear shift control device 401 includes a drive circuit section 41 and a control unit 501, etc. Figure 3 As shown, the drive circuit section 41 has four drive elements 411 to 414, which form an H-bridge circuit. In this embodiment, the drive elements 411 to 414 are MOSFETs, but they can also be IGBTs or the like.

[0032] The high-potential sides of drive elements 411 and 413 are connected by a high-potential side connection line L1. The high-potential side connection line L1 is connected at connection point P1 to the power supply line Lb, which is connected to the high-potential side of battery 90. Furthermore, the low-potential sides of drive elements 412 and 414 are connected by a low-potential side connection line L2. The low-potential side connection line L2 is connected at connection point P2 to the grounding wire Lg. Motor winding 11 is connected to connection point P3 of drive elements 411 and 412 and connection point P4 of drive elements 413 and 414.

[0033] When the motor 10 rotates forward, drive elements 411 and 414 are activated. When the motor 10 rotates in reverse, drive elements 412 and 413 are activated. In this embodiment, when shifting the gear from P to non-P, the motor 10 rotates forward, and when shifting the gear from non-P to P, the motor 10 rotates in reverse. Hereinafter, the action of shifting the gear from P to non-P will be appropriately defined as "disengaging P," and the action of shifting the gear from non-P to P will be defined as "engaging P."

[0034] The current cut-off section 42 is located on the grounding wiring Lg. The current cut-off section 42 is for fail-safe operation; it is normally connected and disconnected by the fault detection IC60 in case of an abnormality. The current sensor 45 is located on the grounding wiring Lg and detects the current in the motor winding 11, i.e., the motor current Im. In the figure, the current cut-off section 42 is labeled "SW". The current sensor 45 can be located at any position capable of detecting the motor current Im, such as on the high-potential side of the drive circuit section 41 or between the motor winding 11 and the drive circuit section 41.

[0035] The control unit 501 is primarily composed of a microcomputer or similar device, and internally includes a CPU, ROM, RAM, I / O devices, and buses connecting these structures (not shown). The processing within the control unit 501 can be software processing, performed by the CPU executing programs pre-stored in a physical storage device such as ROM (i.e., a readable, non-temporary tangible recording medium), or hardware processing based on dedicated electronic circuitry. The control unit 502 of the embodiment described later is the same.

[0036] The control unit 501 includes a main microcomputer 51 as a first control unit and a fault-determining IC 60 as a second control unit. The main microcomputer 51 includes a current acquisition unit 52, a power-on control unit 53, and a power-on status notification unit 54 as functional modules. The current acquisition unit 52 acquires the detection value from the current sensor 45. The power-on control unit 53 controls the on / off operation of the drive elements 411-414, controls the energization of the motor winding 11, and thereby controls the drive of the motor 10.

[0037] The power-on status notification unit 54 notifies the fault determination IC 60 of the power-on status signal corresponding to the power-on command status of the main microcomputer 51. In this embodiment, the power-on status notification unit 54 notifies the fault determination IC 60 of the power-on command status by changing the duty cycle of the power-on status signal. Specifically, when a power-on command is issued to the motor 10, the duty cycle is set to value X1 (e.g., 30%); when a power-off command is issued to the motor 10, the duty cycle is set to value X2 (e.g., 60%); and when a microcomputer fault occurs, the duty cycle is set to value X3 (e.g., 0% or 100%). In addition, states where the output duty cycle is 0% or 100% due to wiring abnormalities, microcomputer faults, etc., are states where a power-on command cannot be issued, and these states are included in the concept of "power-on status signal corresponding to the power-on command status".

[0038] The fault diagnosis IC 60 is constructed from a simpler IC than the main microcomputer 51, but the same microcomputer as the main microcomputer 51 can also be used. The fault diagnosis IC 60 has a current acquisition unit 62, an abnormality monitoring unit 65, and a switch control unit 66 as functional modules. The current acquisition unit 62 acquires the detection value from the current sensor 45. The abnormality monitoring unit 65 performs abnormality monitoring based on the detection value from the current sensor 45 and the power-on status signal acquired from the main microcomputer 51. If an abnormal power-on condition is detected, the switch control unit 66 disconnects the current cut-off unit 42. By disconnecting the current cut-off unit 42, the power supply to the motor winding 11 is cut off.

[0039] based on Figure 4 The flowchart below illustrates the anomaly monitoring process of this embodiment. This process is executed at a predetermined cycle in the fault determination IC60. Hereinafter, the "step" in step S101 will be omitted and simply referred to as "S". The other steps are the same.

[0040] In S101, the fault determination IC60, based on the current detection signal obtained from the current sensor 45, determines whether the state of current flowing in the motor winding 11 has lasted for a duration determination time T or longer. The duration determination time T is a value that will not cause false judgments due to noise, etc., and is set to any time shorter than the time required to switch gears. If it is determined that the motor winding 11 is not energized or the energization time of the motor winding 11 is less than the duration determination time T (S101: No), the process moves to S103, and the current cut-off unit 42 is not operated. That is, the current cut-off unit 42 is maintained in the on state. If it is determined that the energization time of the motor winding 11 is more than the duration determination time T (S101: Yes), the process moves to S102.

[0041] In S102, the fault determination IC60 determines whether the main microcomputer 51 is commanding power-on. In this embodiment, if the duty cycle of the power-on status signal obtained from the main microcomputer 51 is value X1, it is determined that power-on is being commanded. If it is determined that the main microcomputer 51 is commanding power-on (S102: Yes), that is, if the duty cycle of the power-on status signal is value X1, proceed to S103, and the current cut-off unit 42 is not operated. In this case, the main microcomputer 51 issues a power-on command to the motor winding 11, so that current flows in the motor winding 11, which is normal. Therefore, the current cut-off unit 42 remains on, continuously energizing the motor winding 11. If it is determined that the main microcomputer 51 is not commanding power-on (S102: No), that is, if the duty cycle of the power-on status signal is not value X1, proceed to S104.

[0042] In S104, the fault detection IC60 cuts off the current cutoff section 42, thereby cutting off the energization to the motor winding 11. Here, even if the main microcomputer 51 does not control the motor winding 11 by energizing it, current still flows in the motor winding 11, so the energization to the motor winding 11 is cut off. This prevents gear shifting due to unwanted energization.

[0043] As explained above, the gear shift control device 401 of this embodiment can monitor abnormal power supply to the motor 10, which has a motor winding 11, and includes a drive circuit unit 41, a current sensor 45, a current cutoff unit 42, a main microcomputer 51, and a fault determination IC 60. The drive circuit unit 41 switches the power supply to the motor winding 11. The current sensor 45 detects the current flowing through the motor winding 11, i.e., the motor current Im. The current cutoff unit 42 can cut off the motor current Im.

[0044] The main microcomputer 51 includes a power-on control unit 53 that controls the energization of the motor winding 11 and a power-on status notification unit 54 that outputs a power-on status signal corresponding to the power-on command status. The fault diagnosis IC 60 is separately located from the main microcomputer 51 and includes an anomaly monitoring unit 65 that monitors for anomalies based on the detection value of the current sensor 45 and the power-on status signal output from the main microcomputer 51, and performs fault safety measures corresponding to the monitoring results. By utilizing the fault diagnosis IC 60, which is separately located from the main microcomputer 51, for anomaly monitoring, appropriate fault safety measures can be performed even if an anomaly occurs in the main microcomputer 51.

[0045] When the current sensor 45 detects energization of the motor winding 11, and the energization status signal does not indicate that the motor winding 11 is energized, the fault diagnosis IC 60, based on a command from the fault diagnosis IC 60, disconnects the current cutoff section 42, thereby cutting off the energization of the motor winding 11. This allows for the rapid disconnection of unwanted energization. Furthermore, when applied to the drive-by-wire shifting system 1, it prevents accidental gear shifting.

[0046] <Second Implementation Method>

[0047] Figures 5-7 The second embodiment is shown in the figure. For example... Figure 5 As shown, the gear shift control device 402 includes a drive circuit section 41, a current cutoff section 42, a signal cutoff section 43, signal switching sections 441-444, current sensors 46 and 47, and a control unit 502. The control unit 502 includes a main microcomputer 51 and a secondary microcomputer 61. The secondary microcomputer 61 is identical to the fault diagnosis IC 60, and includes a current acquisition section 62, an abnormality monitoring section 65, and a switch control section 66. (Details omitted) Figure 5The diagram shows the current acquisition unit 62, the abnormality monitoring unit 65, and the switch control unit 66. In addition, the current cut-off unit 42 is labeled as "SWF", the signal cut-off unit 43 is labeled as "SWA", and the signal switching units 441 to 444 are labeled as "Switch 1 to 4".

[0048] The signal cutoff unit 43 and signal switching units 441-444 are controlled by the switching control unit 66 of the main microcomputer 51 and the auxiliary microcomputer 61. The signal cutoff unit 43 is normally connected and disconnected by the auxiliary microcomputer 61 in case of power failure. When the signal cutoff unit 43 is connected, commands from the main microcomputer 51 are transmitted to the drive elements 411-414 via the signal switching units 441-444. Thus, the drive elements 411-414 are controlled by the main microcomputer 51 to switch on and off. Furthermore, if the signal cutoff unit 43 is disconnected, the transmission of commands from the main microcomputer 51 to the drive elements 411-414 is interrupted.

[0049] The signal switching units 441-444 are configured such that, under normal conditions, the main microcomputer 51 controls the on / off operation, and under abnormal power conditions, the auxiliary microcomputer 61 can control the on / off operation. Based on Figure 6 The operation of signal switching units 441 to 444 will be explained below. Related to the on / off switching of signal switching units 441 to 444, instructions from the autonomous microcomputer 51 are set to SGN_M1 to SGN_M4, and instructions from the slave microcomputer 61 are set to SGN_S1 to SGN_S4. The "1" to "4" at the end correspond to signal switching units 441 to 444 respectively. Figure 6 This is recorded as "#". Furthermore, the on / off command is set to "1", and the off / open command is set to "0". The following explanation will use the on / off operation of the signal switching unit 441 as an example. Since the parts corresponding to "#" in the signal switching units 442 to 444 can be rewritten, their explanations are omitted.

[0050] When both commands SGN_M1 and SGN_S1 are cut-off commands, the signal switching unit 441 is set to cut-off. When one of commands SGN_M1 and SGN_S1 is an on command and the other is a cut-off command, the signal switching unit 441 is set to on.

[0051] In this embodiment, under normal conditions, the secondary microcomputer 61 always cuts off the instruction SGN_S1. Therefore, the on / off operation of the signal switching unit 441 is controlled according to the instruction SGN_M1 from the primary microcomputer 51. On the other hand, in the event of a power failure, the secondary microcomputer 61 cuts off the signal cutting-off unit 43, thereby cutting off the transmission of the instruction SGN_M1 to the signal switching unit 441. If the signal cutting-off unit 43 is cut off, the instruction SGN_M1 output to the signal switching unit 441 becomes a cutting-off instruction. Therefore, the on / off operation of the signal switching unit 441 is controlled according to the instruction SGN_S1 from the secondary microcomputer 61.

[0052] That is, under normal conditions, command SGN_S1 becomes a cut-off command, and under abnormal power conditions, command SGN_M1 becomes a cut-off command. Therefore, the scenario where both commands SGN_M1 and SGN_S1 become on commands is not considered. Thus, when both commands SGN_M1 and SGN_S1 are on commands, it is an abnormal state, and therefore the signal switching unit 441 is cut off.

[0053] return Figure 5 A first current sensor 46 is positioned where current flows when the motor 10 rotates in the forward direction and where no current flows when the motor 10 rotates in the reverse direction, detecting the current during forward rotation. Specifically, the first current sensor 46 is located on the low-potential side connection line L2, closer to the drive element 414 than the connection point P2. A second current sensor 47 is positioned where current flows when the motor 10 rotates in the reverse direction and where no current flows when the motor 10 rotates in the forward direction, detecting the current during reverse rotation. Specifically, the second current sensor 47 is located on the low-potential side connection line L2, closer to the drive element 412 than the connection point P2. Thus, the rotation direction of the motor 10 can be detected based on the detection values ​​of the current sensors 46 and 47. In the figure, the first current sensor 46 is labeled A1, and the second current sensor 47 is labeled A2.

[0054] The power-on status notification unit 54 notifies the secondary microcomputer 61 of a power-on command signal corresponding to the power-on command status of the primary microcomputer 51. In this embodiment, the power-on command signal is generated in a manner that can determine the rotation direction of the motor 10. Specifically, when a command to engage P gear is issued to make the motor 10 rotate in the forward direction, the duty cycle is set to value Y1 (e.g., 30%); when a command to cut off power to the motor 10 is issued, the duty cycle is set to value Y2 (e.g., 60%); when a command to disengage P gear is issued to make the motor 10 rotate in the reverse direction, the duty cycle is set to value Y3 (e.g., 90%); and in the event of a microcomputer malfunction, the duty cycle is set to value Y4 (e.g., 0% or 100%).

[0055] based on Figure 7 The flowchart below illustrates the anomaly monitoring process of this embodiment. This process is executed in the sub-microcomputer 61 at predetermined cycles. In S201, the sub-microcomputer 61 determines whether the main microcomputer 51 has malfunctioned. Here, if the duty cycle of the power-on state signal is value Y4, it is determined that the main microcomputer 51 is malfunctioning. If the main microcomputer 51 is determined to be malfunctioning (S201: Yes), that is, if the duty cycle of the communication state signal is value Y4, the process moves to S202, and the current cut-off section 42 is cut off. If the main microcomputer 51 is determined not to be malfunctioning (S201: No), that is, if the duty cycle of the communication state signal is not value Y4, the process moves to S203.

[0056] In S203, the sub-microcomputer 61, based on the current detection signal obtained from the first current sensor 46, determines whether the state of positive current flowing in the motor winding 11 has lasted for a duration determination time T1 or more. The duration determination time T1 is the same as the duration determination time T in the above embodiment, and is a value that will not cause false determinations due to noise, etc., and is set to an arbitrary time shorter than the time required to switch gears. Furthermore, it may be equal to or different from the times T2 to T4 described later. If it is determined that the positive energization time of the motor winding 11 is less than the duration determination time T1 (S203: No), proceed to S209. If it is determined that the positive energization time of the motor winding 11 is more than the duration determination time T1 (S203: Yes), proceed to S204.

[0057] In S204, the slave microcomputer 61 determines whether the master microcomputer 51 is instructing the release of the P position. If it determines that the master microcomputer 51 is instructing the release of the P position (S204: Yes), that is, when the duty cycle of the communication status signal is value Y3, the desired power is applied, and therefore the process moves to S215 to maintain the switch control state. Specifically, the current cutoff section 42 and the signal cutoff section 43 are turned on, and the master microcomputer 51 continues to control the drive elements 411 to 414. If it determines that the master microcomputer 51 is not instructing the release of the P position (S204: No), that is, when the duty cycle of the communication status signal is not value Y3, the process moves to S205. In S205, the slave microcomputer 61 determines that an undesirable power supply different from the instruction of the master microcomputer 51 has occurred, and the signal cutoff section 43 is turned off.

[0058] In S206, the sub-microcomputer 61, based on the current detection signal obtained from the first current sensor 46, determines whether the state of positive current flowing in the motor winding 11 has lasted for a duration determination time T2 or more. If it is determined that the positive energization time of the motor winding 11 is less than the duration determination time T2 (S206: No), proceed to S208. If it is determined that the positive energization time of the motor winding 11 is more than the duration determination time T2 (S206: Yes), proceed to S207.

[0059] In S207, even though the signal cut-off section 43 has been cut off, current continues to flow in the motor winding 11. Therefore, the sub-microcomputer 61 determines that a wiring fault has occurred and cuts off the power supply to the motor winding 11 by cutting off the current cut-off section 42.

[0060] Step S208 is a procedure where, even if the instruction from the main microcomputer 51 is not a P-gear disengagement instruction, the energization in the P-gear disengagement direction (i.e., the forward rotation direction) has lasted for a determination time T1 or more, and the energization to the motor winding 11 has been cut off by the signal cut-off unit 43 according to the instruction from the auxiliary microcomputer 61. In S208, to avoid unwanted gear shifting, energization control is performed by moving the stop roller 26 in the P-gear engagement direction according to the instruction from the auxiliary microcomputer 61. Specifically, by activating the signal switching units 442 and 443, the drive elements 412 and 413 are activated, allowing a current flowing in the reverse rotation direction through the motor winding 11. After the reverse current has flowed through the motor winding 11 for a return time T5, the auxiliary microcomputer 61 disconnects the signal switching units 442 and 443, thereby cutting off the drive elements 412 and 413 and ending the energization. The return time T5 is set accordingly to the time required to engage P gear.

[0061] In S209, where the forward energization time of motor winding 11 is determined to be less than the duration determination time T1 (S203: No), the sub-microcomputer 61 determines, based on the current detection signal obtained from the second current sensor 47, whether the state of reverse current flowing in motor winding 11 has lasted for more than the duration determination time T3. If the reverse energization time of motor winding 11 is determined to be less than the duration determination time T3 (S209: No), motor winding 11 is in a non-energized state, and therefore the process moves to S215 to maintain the switch control state. That is, the current cutoff section 42 and the signal cutoff section 43 are turned on, and the control in the main microcomputer 51 continues. If the reverse energization time of motor winding 11 is determined to be more than the duration determination time T3 (S209: Yes), the process moves to S210.

[0062] In S210, the slave microcomputer 61 determines whether the master microcomputer 51 is instructing the main microcomputer 51 to engage the P position. If it determines that the master microcomputer 51 is instructing the main microcomputer 51 to engage the P position (S210: Yes), that is, when the duty cycle of the communication status signal is value Y1, the desired power is applied, and therefore the process moves to S215 to maintain the switch control state. Specifically, the current cutoff section 42 and the signal cutoff section 43 are turned on, and the master microcomputer 51 continues to control the drive elements 411 to 414. If it determines that the master microcomputer 51 is not instructing the main microcomputer 51 to engage the P position (S210: No), that is, when the duty cycle of the communication status signal is not value Y1, the process moves to S211. In S211, the slave microcomputer 61 determines that an undesirable power supply different from the instruction of the master microcomputer 51 has been generated, and the signal cutoff section 43 is turned off.

[0063] In S212, the sub-microcomputer 61, based on the current detection signal obtained from the second current sensor 47, determines whether the state of reverse current flowing in the motor winding 11 has lasted for the duration determination time T4. If it is determined that the reverse energization time of the motor winding 11 is less than the duration determination time T4 (S212: No), proceed to S214. If the reverse energization time of the motor winding 11 is greater than or equal to the duration determination time T4 (S212: Yes), proceed to S213.

[0064] In S213, even though the signal cut-off section 43 has been cut off, current continues to flow in the motor winding 11. Therefore, the sub-microcomputer 61 determines that a wiring fault has occurred and cuts off the power supply to the motor winding 11 by cutting off the current cut-off section 42.

[0065] Step S214 is a procedure where, even if the instruction from the main microcomputer 51 is not a P-gear engagement instruction, the energization in the P-gear engagement direction (i.e., the reverse rotation direction) has lasted for a determination time T3 or more, and the energization to the motor winding 11 has been cut off by the signal cut-off unit 43 according to the instruction from the auxiliary microcomputer 61. In S214, to avoid unwanted gear shifting, energization control is performed by moving the stop roller 26 in the P-gear release direction according to the instruction from the auxiliary microcomputer 61. Specifically, by activating the signal switching units 441 and 444, the drive elements 411 and 414 are activated, allowing current to flow in the motor winding 11 in the forward rotation direction. After the forward current has flowed in the motor winding 11 for a return time T6, the auxiliary microcomputer 61 disconnects the signal switching units 441 and 444, thereby cutting off the drive elements 411 and 414 and ending the energization. The return time T6 is set accordingly to the time required to disengage from Park (P). The return times T5 and T6 can be equal or different.

[0066] Alternatively, the process in S206 can be omitted, and the P gear can be engaged and powered on without performing a power-on status determination after the signal cut-off unit 43 is disconnected. Similarly, the process in S212 can be omitted, and the P gear can be disengaged and powered on without performing a power-on status determination after the signal cut-off unit 43 is disconnected.

[0067] In this embodiment, the configuration includes a signal cutoff unit 43 and signal switching units 441-444. When the main microcomputer 51 malfunctions and the signal cutoff unit 43 is cut off, the auxiliary microcomputer 61 can control the on / off operation of the drive elements 411 and 414. Furthermore, if unwanted energization is detected, a reverse current flows under the instruction of the auxiliary microcomputer 61, thereby driving the stop roller 26 in the return direction. This prevents accidental gear shifting and maintains the original gear position.

[0068] The gear shift control device 402 includes a signal cutoff unit 43, which can cut off the on / off commands from the main microcomputer 51 to all drive elements 411 to 414 of the drive circuit unit 41 via the auxiliary microcomputer 61. Current sensors 46 and 47 can detect the direction of motor current Im.

[0069] When the sub-microcomputer 61 detects an abnormality in the rotation direction of the motor 10, which is inconsistent with the rotation direction of the motor 10 corresponding to the energizing direction of the motor current Im detected by the current sensors 46 and 47, the sub-microcomputer 61 cuts off the signal cut-off section 43 according to the instruction from the sub-microcomputer 61, thereby cutting off the motor current Im.

[0070] Furthermore, if the sub-microcomputer 61 is unable to cut off the motor current Im by cutting off the signal cutting-off unit 43, it cuts off the motor current Im by cutting off the current cutting-off unit 42. This prevents the motor 10 from rotating in an unwanted direction. When applied to the drive-by-wire shifting system 1, it prevents erroneous gear shifting.

[0071] The gear shift control device 402 includes signal switching units 441 to 444, which are provided for each drive element 411 to 414. These units can switch whether the drive elements 411 to 414 are switched on or off under the command of the main microcomputer 51 or under the command of the auxiliary microcomputer 61. When the auxiliary microcomputer 61 detects an abnormality in the rotation direction, it controls the signal switching units 441 to 444 to change the rotation direction of the motor 10 to the opposite direction to the direction in which the abnormality was detected, while the signal cutting-off unit 43 is cut off. Therefore, for example, when applied to the drive-by-wire shift system 1, the gear position before the motor 10 is energized can be maintained, preventing unwanted gear shifts.

[0072] In the implementation, the gear shift control devices 401 and 402 correspond to the "abnormal monitoring device", the current sensors 45 to 47 correspond to the "current detection unit", the main microcomputer 51 corresponds to the "first control unit", and the fault determination IC 60 or the auxiliary microcomputer 61 corresponds to the "second control unit".

[0073] <Other Implementation Methods>

[0074] In the above embodiment, the power-on status notification unit notifies the second control unit of the power-on command status by changing the duty cycle in accordance with the power-on command status. In other embodiments, the power-on command status can also be notified by methods other than changing the duty cycle, such as setting multiple signal lines and outputting on / off signals corresponding to the power-on command status.

[0075] In the above embodiment, the motor is a brushed motor, and the drive circuit is an H-bridge circuit. In other embodiments, the motor can be a motor other than a brushed motor, such as a switched reluctance motor or a DC brushless motor. Furthermore, the drive circuit only needs to be configured to correspond with the circuit structure of the motor.

[0076] In the above embodiment, the stop plate has two recesses. In other embodiments, the number of recesses is not limited to two; for example, a recess may be provided for each gear position. Furthermore, the gear shifting mechanism, parking locking mechanism, etc., may also differ from the above embodiment.

[0077] In the above embodiments, a speed reducer is provided between the motor shaft and the output shaft. Details of the speed reducer are not mentioned in the above embodiments; for example, it can be any structure such as a cycloidal gear, planetary gear, a spur gear that transmits torque from a reduction mechanism substantially coaxial with the motor shaft to the drive shaft, or a combination of these types of speed reducers. Furthermore, in other embodiments, the speed reducer between the motor shaft and the output shaft may be omitted, and a mechanism other than the speed reducer may be provided.

[0078] The control unit and method described in this disclosure can also be implemented using a dedicated computer configured with a processor and memory programmed to perform one or more functions embodied in a computer program. Alternatively, the control unit and method described in this disclosure can also be implemented using a dedicated computer configured with a processor using one or more dedicated hardware logic circuits. Alternatively, the control unit and method described in this disclosure can also be implemented using one or more dedicated computers configured with a combination of a processor and memory programmed to perform one or more functions and a processor containing one or more hardware logic circuits. Furthermore, the computer program can also be stored as instructions executable by a computer on a computer-readable non-transitional tangible recording medium. Therefore, this disclosure is not limited to any of the above embodiments and can be implemented in various ways without departing from its spirit.

[0079] This disclosure has been described in accordance with embodiments. However, this disclosure is not limited to these embodiments and constructions. This disclosure also includes various modifications and equivalent variations. In addition, various combinations and methods, as well as other combinations and methods that include only one element, or include more or fewer elements, also fall within the scope and spirit of this disclosure.

Claims

1. An anomaly monitoring device for monitoring abnormal energizing of a motor having motor windings, characterized in that, have: The drive circuit section switches the energization of the motor windings. The current detection unit detects the current flowing through the motor windings, i.e., the motor current. A current cutoff section, which is capable of cutting off the motor current; The first control unit includes an energizing control unit for controlling the energizing of the motor windings and an energizing status notification unit for outputting an energizing status signal corresponding to the energizing command status. as well as The second control unit is separately disposed from the first control unit and has an anomaly monitoring unit that monitors anomalies based on the detection value of the current detection unit and the power-on status signal, and performs fault safety handling corresponding to the monitoring results. The anomaly monitoring device includes a signal cutoff unit, which can cut off the on / off commands from the first control unit to all drive elements constituting the drive circuit unit via the second control unit. The current detection unit is capable of detecting the direction of the motor current. When the second control unit detects an abnormality in the rotation direction of the motor that is inconsistent with the rotation direction of the motor that is inconsistent with the rotation direction of the motor that is inconsistent with the rotation direction of the motor that is inconsistent with the energizing state signal, the second control unit cuts off the signal cutoff unit according to the instruction from the second control unit, thereby cutting off the motor current.

2. The anomaly monitoring device according to claim 1, characterized in that, When the current detection unit detects that the motor winding is energized, and the energization status signal does not indicate that the motor winding is energized, the second control unit, according to the instruction from the second control unit, cuts off the current cut-off unit, thereby cutting off the motor current.

3. The anomaly monitoring device according to claim 1, characterized in that, The anomaly monitoring device includes a signal switching unit, which is provided for each of the driving elements and is capable of switching whether the driving element is turned on or off under the command of the first control unit or under the command of the second control unit. When the second control unit detects the abnormality of the rotation direction inconsistency, it controls the signal switching unit to change the rotation direction of the motor to the opposite direction when the abnormality of the rotation direction inconsistency is detected, while the signal cutting-off unit is in a state of cutting off.

4. The anomaly monitoring device according to claim 1 or 3, characterized in that, If the second control unit is unable to cut off the motor current by cutting off the signal cutting-off unit, it cuts off the motor current by cutting off the current cutting-off unit.

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