In-vehicle control device

Abstract

The invention provides an in-vehicle control device. Before the operation of the electric parking brake is completed, the possibility of impact caused by torsion of the drive shaft when the electric parking brake is released due to the release of the foot brake is stored as a history. When an electric parking brake is operated according to a shift operation while the vehicle is stopped in a state in which the front-rear direction of the vehicle is inclined, a release of foot brake is detected from the start of the operation of the electric parking brake to the completion of the operation, or rotation of wheels of an axle to which the electric parking brake is attached is detected. The possibility of shock is stored as the possibility of occurrence of shock when the electric parking brake is released.

Description

Technical Field

[0001] This disclosure relates to an on-board control device, and more specifically to an on-board control device mounted on a vehicle equipped with an electric parking brake. Background Technology

[0002] As a vehicle-mounted control device, an example has been proposed whereby the braking force provided by the foot brake is maintained even after the shift gear has been switched to the parking gear, even if the driver quickly releases the foot brake (see, for example, Patent Document 1). In this device, by maintaining the braking force provided by the foot brake, wheel rotation is suppressed, and drive shaft torsion is suppressed. Therefore, when the vehicle is started again and the shift gear is switched from the parking gear to the non-parking gear, the impact caused by drive shaft torsion is suppressed.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2020-100312 Summary of the Invention

[0006] However, in the aforementioned vehicle control device, even when the driver releases the foot brake, the foot brake is still required to maintain braking force until the electric parking brake is activated by shifting the gear to the parking position.

[0007] The main objective of the vehicle-mounted control device disclosed herein is to store as history the possibility of an impact caused by the torsion of the drive shaft when the electric parking brake is released, since the foot brake is released before the electric parking brake is fully activated.

[0008] The vehicle-mounted control device disclosed herein employs the following means to achieve the aforementioned main objectives.

[0009] The vehicle-mounted control device disclosed herein is mounted on a vehicle equipped with an electric parking brake, characterized in that...

[0010] When the vehicle-mounted control device stops the vehicle while it is tilted in the longitudinal direction and activates the electric parking brake according to the gear shift operation, it stores the possibility of impact as if there is a possibility of impact when the electric parking brake is released, or if it detects the rotation of the wheel of the axle on which the electric parking brake is installed, from the start of the electric parking brake to the completion of the action.

[0011] In the vehicle control device disclosed herein, when the vehicle is parked with its front and rear tilted and the electric parking brake is activated by shifting gears, if the release of the foot brake is detected from the start of the electric parking brake operation until its completion, or if rotation of the wheel on the axle on which the electric parking brake is mounted is detected, an impact possibility is stored as a possibility that an impact may occur when the electric parking brake is released. That is, the possibility that an impact may occur due to the torsion of the drive shaft when the electric parking brake is released because the foot brake is released before the electric parking brake operation is completed is stored as history. This allows for the determination of the cause of impacts or abnormal noises when the electric parking brake is released.

[0012] In the vehicle control device disclosed herein, the possibility of an impact can be stored when the electric parking brake is released according to a gear shift operation, and the occurrence of an impact can be stored when the vehicle's acceleration in the longitudinal direction is above a predetermined value immediately after the electric parking brake is released. This allows for more reliable storage of impacts and abnormal noises occurring when the electric parking brake is released, providing material for later determination of the cause of such impacts and abnormal noises. Attached Figure Description

[0013] Figure 1 This is a schematic structural diagram showing the structure of an electric vehicle 20 equipped with an on-board control device as an embodiment of the present disclosure.

[0014] Figure 2 This is a flowchart illustrating an example of the shift lock action when the gear lever 71 is shifted from non-parking to parking.

[0015] Figure 3 This is a flowchart illustrating an example of the gear shifting and unlocking action when the gear lever 71 is shifted from the parking position to the non-parking position. Detailed Implementation

[0016] Next, the method (implementation method) for carrying out this disclosure will be described. Figure 1 This is a schematic structural diagram showing the structure of an electric vehicle 20 equipped with an on-board control device as an embodiment of this disclosure. The electric vehicle 20 of the embodiment is as follows... Figure 1 As shown, the device includes a motor 22, an inverter 24, an electric parking brake 27, a high-voltage battery 30, and an electronic control unit 60. In this embodiment, the electronic control unit 60 corresponds to a "vehicle-mounted control device".

[0017] Motor 22 is configured, for example, as a synchronous generator motor. The rotor of motor 22 (not shown) is connected to a drive shaft 26 via a differential gear 28 and drive wheels 29a and 29b. A rotational position detection sensor 22a is installed on motor 22 to detect the rotational position of the rotor.

[0018] Inverter 24 is configured as a known inverter circuit with 6 transistors and 6 diodes. Inverter 24 is connected to a high-voltage power line 32 connected to a high-voltage battery 30. Inverter 24 converts the DC power from the high-voltage battery 30 into three-phase AC power via PWM control and applies it to motor 22 to drive motor 22.

[0019] The high-voltage battery 30 is configured as, for example, a lithium-ion battery. The high-voltage battery 30 is connected to a high-voltage power line 32. Voltage sensors 31a for detecting the battery voltage Vb are installed at both terminals of the high-voltage battery 30. Current sensors 31b for detecting the battery current Ib are installed at the terminals of the high-voltage battery 30. A system main relay 34 for connecting or disconnecting the high-voltage battery 30 is installed on the high-voltage power line 32. A smoothing capacitor 36 is also installed on the high-voltage power line 32. A voltage sensor 36a for detecting the high-voltage voltage VH is installed on the high-voltage power line 32.

[0020] The electric parking brake 27 is mounted on the drive shaft 26 and is activated when the gear lever 71 is shifted from a non-parking position (a position other than P) to a parking position (P), and is released when the gear lever 71 is shifted from a parking position to a non-parking position.

[0021] The electronic control unit 60 is configured as a microcomputer centered on the CPU 62. In addition to the CPU 62, the electronic control unit 60 also has a ROM 64, RAM 66, flash memory (not shown), input ports (not shown), and output ports (not shown).

[0022] The electronic control unit 60 receives, via its input port, the rotational position θm detected by the rotational position detection sensor 22a, the battery voltage Vb detected by the voltage sensor 31a, the battery current Ib detected by the current sensor 31b, and the high-voltage system voltage VH detected by the voltage sensor 36a. The electronic control unit 60 also receives the start signal ST from the start switch 70, the gear position SP detected by the gear lever position sensor 72 mounted on the gear lever 71, the acceleration opening Acc detected by the accelerator pedal position sensor 74 mounted on the accelerator pedal 73, and the brake pedal position BP detected by the brake pedal position sensor 76 mounted on the brake pedal 75. The electronic control unit 60 also receives the vehicle speed V detected by the vehicle speed sensor 78, the acceleration α detected by the acceleration sensor 80, the road slope θr from the slope sensor 82, and the wheel speeds Wva and Wvb from the wheel speed sensors 86a and 86b.

[0023] The electronic control unit 60 outputs switching control signals to the inverter 24, drive control signals to the electric parking brake 27, drive control signals to the DC / DC converter 44, and display control signals to the display 84 via the output port.

[0024] The electronic control unit 60 calculates the rotational speed Nm of the motor 22 based on the rotational position θ of the rotor of the motor 22. The electronic control unit 60 calculates the state of charge (SOC) of the high-voltage battery 30 based on the cumulative value of the battery current Ib.

[0025] Next, the operation of the electric vehicle 20 according to the embodiment will be explained, in particular the operation when the gear lever 71 is changed from a non-parking gear (a gear other than P gear) to a parking gear (P gear) when the vehicle is parked, and the operation when the gear lever 71 is changed from a parking gear to a non-parking gear. Figure 2 This is a flowchart illustrating an example of the shift lock operation when the gear lever 71 is shifted from non-parking to parking. Figure 3 This is a flowchart illustrating an example of the gear shift unlocking operation when the gear lever 71 is shifted from the parking position to the non-parking position. The following sections will explain this in detail.

[0026] Action during gear shift lock ( Figure 2 In the process, the vehicle stops by the driver's foot brake action (step S100) (step S110), and the driver performs a shift lock operation to put the gear lever 71 into the parking gear (P gear) (step S120). During the shift lock operation, the electric parking brake 27, which is linked to the operation, is activated (opened).

[0027] After the electric parking brake 27 is activated ("Yes" in step S130), and after the foot brake is released after the electric parking brake 27 is activated (steps S140 and S150), it is determined that there is no possibility of impact or abnormal noise when shifting gears on a slope (step S160), and this action ends.

[0028] After the electric parking brake 27 is activated ("Yes" in step S130), and before the foot brake is released after the electric parking brake 27 is activated (steps S240, S250), if the wheel speeds Wva and Wvb detected by the wheel speed sensors 86a and 86b do not rotate in the drive wheels 29a and 29b ("No" in step S260), it is determined that the possibility of impact or abnormal noise during gear shifting and unlocking on a slope is moderate (step S270), and the possibility of impact or abnormal noise during gear shifting and unlocking on a slope is moderate is stored as history (step S400).

[0029] After the electric parking brake 27 is activated ("Yes" in step S130), when the foot brake is released before the electric parking brake 27 is activated (steps S240, S250), and when the drive wheels 29a and 29b are rotating according to the wheel speeds Wva and Wvb ("Yes" in step S260), it is determined that there is a high probability of impact or abnormal noise when shifting gears on a slope (step S350), and the probability of impact or abnormal noise when shifting gears on a slope is stored as history (step S400).

[0030] Before the electric parking brake 27 is activated ("No" in step S130), when the foot brake is released (step S340), it is determined that there is a high probability of impact or abnormal noise when shifting gears on a slope (step S350), and the probability of impact or abnormal noise when shifting gears on a slope is stored as history (step S400).

[0031] When the possibility of a shock or abnormal noise occurring during gear shifting on a slope is stored as moderate or high in history, when the system issues a warning when the start switch 70 is turned on to start the system ("Yes" in step S410), or when the system is started after the system is turned off (steps S420 and S430), the indication that there is a possibility of a shock or abnormal noise occurring during gear shifting on a slope is displayed on the display 84 (step S440), and this action ends.

[0032] Thus, if, after the gear shift lock operation is performed but before the electric parking brake 27 is fully activated, the foot brake is released, or rotation is detected in the drive wheels 29a and 29b, it is determined that the likelihood of impact or abnormal noise occurring during gear shift unlocking on a slope is moderate or high, and this is stored as history. This stored history can serve as material for later determining the cause of impact or abnormal noise when the electric parking brake 27 is released.

[0033] Actions during gear shifting and unlocking ( Figure 3 In step S500, when the driver performs a gear shifting operation by moving the gear lever 71 from the parking gear (P gear) to a non-parking gear (a gear other than P gear), the system stores a history indicating that the probability of impact or abnormal noise during gear shifting on a slope is moderate or high ("Yes" in step S510). When the acceleration α detected by the acceleration sensor 80 is above the threshold when the electric parking brake 27 is released ("Yes" in step S520), it is determined that impact or abnormal noise occurred during gear shifting on a slope (step S530), and the history of impact or abnormal noise during gear shifting on a slope is stored (step S540), thus ending this operation. Furthermore, if there is no history stored regarding the possibility of impact or abnormal noise occurring during gear shifting and unlocking on a slope ("No" in step S510), and if the acceleration α detected by the acceleration sensor 80 when the electric parking brake 27 is released is less than a threshold ("No" in step S520), it is determined that no impact or abnormal noise occurs during gear shifting and unlocking on a slope, and this operation ends. Thus, if a history is stored during the gear shifting and unlocking operation where the possibility of impact or abnormal noise occurring during gear shifting and unlocking on a slope is moderate or high, and the acceleration α detected by the acceleration sensor 80 when the electric parking brake 27 is released is above a threshold, then the history of impact or abnormal noise occurring during gear shifting and unlocking on a slope is stored. This stored history can serve as material for later determining the cause of impact or abnormal noise when the electric parking brake 27 is released.

[0034] The above describes the implementation of this disclosure, but this disclosure is not limited to such implementation at all, and can of course be implemented in various ways without departing from the spirit of this disclosure.

[0035] [Industry Applicability]

[0036] This disclosure can be used in industries such as the manufacturing of vehicle-mounted control devices for automobiles.

[0037] (Symbol Explanation)

[0038] 20: Electric vehicle; 22: Motor; 24: Inverter; 26: Drive shaft; 27: Electric parking brake; 28: Differential gear; 29a, 29b: Drive wheels; 30: High-voltage battery; 31a: Voltage sensor; 31b: Current sensor; 32: High-voltage power line; 34: System main relay; 36: Capacitor; 36a: Voltage sensor; 60: Electronic control unit; 62: CPU; 64: ROM; 66: RAM; 70: Starter switch; 71: Gear shift lever; 72: Gear position sensor; 73: Accelerator pedal; 74: Accelerator pedal position sensor; 75: Brake pedal; 76: Brake pedal position sensor; 78: Vehicle speed sensor; 80: Acceleration sensor; 82: Slope sensor; 84: Display; 86a, 86b: Wheel speed sensors.

Claims

1. A vehicle-mounted control device, mounted on a vehicle equipped with an electric parking brake, characterized in that, When the vehicle-mounted control device stops the vehicle while it is tilted in the longitudinal direction and activates the electric parking brake according to the gear shift operation, it stores the possibility of impact as if there is a possibility of impact when the electric parking brake is released, or if it detects the rotation of the wheel of the axle on which the electric parking brake is installed, from the start of the electric parking brake to the completion of the action.

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