Motor drive circuit of electronic parking brake system

Abstract

This invention relates to a motor drive circuit for an electronic parking brake system, comprising: a first motor and a second motor for releasing or activating parking brakes applied to different wheels respectively; a first electronic control unit and a second electronic control unit for driving and controlling the first motor and the second motor respectively; when the first electronic control unit is driving the first motor and the second motor, the second electronic control unit does not intervene in driving the first motor and the second motor; the second electronic control unit only drives and controls the first motor and the second motor when there is an abnormality in the first electronic control unit.

Description

Technical Field

[0001] This invention relates to a motor drive circuit for an electronic parking brake system, and more specifically, to a motor drive circuit for an electronic parking brake system capable of driving an additional motor while improving safety. Background Technology

[0002] The Electronic Parking Brake (EPB), also known as an automatic parking system or automatic parking system, is designed to lock the brakes when a vehicle is stopped for a certain period of time, by sensing the vehicle's speed, engine rotation, and whether the brakes are engaged.

[0003] Electronic parking brakes use a motor driven by electronic signals to fix a roller or disk.

[0004] The mechanical configuration of this electronic parking brake is described in Patent No. 10-2122756 (Electronic Parking Brake for Vehicles, granted on June 9, 2020).

[0005] The electronic parking brake system includes a drive circuit for driving the motor, and can put the vehicle into a release or apply state by driving the motor.

[0006] Normally, when one or more of the components that make up the electronic control unit (ECU) malfunction, the normal operation of the electronic parking brake system cannot be expected.

[0007] Furthermore, the electronic parking brake system cannot be expected to function properly if multiple current supply units malfunction, thus reducing its reliability. Summary of the Invention

[0008] Technical problems to be solved

[0009] The technical problem to be solved by the present invention is to provide a motor drive circuit for an electronic parking brake system that can operate normally even if a part of it malfunctions.

[0010] More specifically, the technical problem to be solved by the present invention is to provide a motor drive circuit, providing multiple motor drive circuits, so that they can operate normally even if some of them malfunction.

[0011] Meanwhile, the aim is to provide a motor drive circuit that can drive and control other motors by using one side of the ECU of the motor drive circuit with a redundant structure.

[0012] means for solving problems

[0013] The motor drive circuit of the electronic parking brake system of the present invention for solving the problems described above includes: a first motor and a second motor, which release or activate parking brakes applied to different wheels respectively; a first ECU and a second ECU, which drive and control the first motor and the second motor respectively; the second ECU can, while the first ECU is driving the first motor and the second motor, not intervene in driving the first motor and the second motor, and only drive and control the first motor and the second motor when the first ECU is malfunctioning.

[0014] In an embodiment of the present invention, the first ECU may include: a first MCU (Microcontroller Unit) that confirms the release or activation conditions of the electronic parking brake; a first drive unit that switches control signals according to the control output of the first MCU; a first current supply unit that switches according to the switching control signal of the first drive unit to change the direction of the current and supply it to each of the first motor and the second motor; and a first selection unit that selectively supplies the current from the first current supply unit to the first motor and the second motor.

[0015] In an embodiment of the present invention, the second ECU may include: a second MCU that confirms the release or activation conditions of the electronic parking brake; a second drive unit that switches control signals according to the control output of the second MCU; a second current supply unit that switches according to the switching control signal of the second drive unit to change the direction of the current and supply it to each of the first motor and the second motor; and a second selection unit that selectively supplies the current from the second current supply unit to the first motor and the second motor.

[0016] In an embodiment of the present invention, the first ECU may include: a first MCU that confirms the release or activation conditions of the electronic parking brake; a first drive unit that switches control signals according to the control output of the first MCU; a first current supply unit that switches according to the switching control signal of the first drive unit to change the direction of the current and supply it to each of the first motor and the second motor; and a first selection unit that controls the current supplied to the first current supply unit from the battery.

[0017] In an embodiment of the present invention, the second ECU may include: a second MCU that confirms the release or activation conditions of the electronic parking brake; a second drive unit that switches control signals according to the control output of the second MCU; a second current supply unit that switches according to the switching control signal of the second drive unit to change the direction of the current and supply it to each of the first motor and the second motor; and a second selection unit that controls the current supplied to the battery by the second current supply unit.

[0018] In addition, the present invention provides a motor drive circuit, characterized in that it includes: a first motor and a second motor, which release or activate parking brakes applied to different wheels respectively; a first ECU and a second ECU, which drive and control the first motor and the second motor respectively; the second ECU, which does not intervene in driving the first motor and the second motor when the first ECU is driving the first motor and the second motor, only drives and controls the first motor and the second motor when the first ECU is malfunctioning, and drives and controls a third motor when the first ECU is driving the first motor and the second motor.

[0019] In an embodiment of the present invention, the first ECU may include: a first MCU that confirms the release or activation conditions of the electronic parking brake; a first drive unit that switches control signals according to the control output of the first MCU; a first current supply unit that switches according to the switching control signal of the first drive unit to change the direction of the current and supply it to each of the first motor and the second motor; and a first selection unit that selectively provides the current from the first current supply unit to the first motor and the second motor.

[0020] In an embodiment of the present invention, the second ECU may include: a second MCU that confirms the release or activation conditions of the electronic parking brake; a second drive unit that switches control signals according to the control output of the second MCU; a second current supply unit that switches according to the switching control signal of the second drive unit to change the direction of the current and supply it to each of the first motor and the second motor; and a second selection unit that selectively provides the current from the second current supply unit to the first motor and the second motor.

[0021] In an embodiment of the present invention, the first ECU may include: a first MCU that confirms the release or activation conditions of the electronic parking brake; a first drive unit that switches control signals according to the control output of the first MCU; a first current supply unit that switches according to the switching control signal of the first drive unit to change the direction of the current and supply it to each of the first motor and the second motor; and a first selection unit that controls the current supplied to the first current supply unit from the battery.

[0022] In an embodiment of the present invention, the second ECU may include: a second MCU that confirms the release or activation conditions of the electronic parking brake; a second drive unit that switches control signals according to the control output of the second MCU; a second current supply unit that switches according to the switching control signal of the second drive unit to change the direction of the current and supply it to each of the first motor and the second motor; and a second selection unit that controls the current supplied to the battery by the second current supply unit.

[0023] In an embodiment of the present invention, the first ECU may further include: a third current supply unit for selectively supplying current from the first current supply unit to the third motor, and a third selection unit for controlling the supply of battery power to the third current supply unit.

[0024] In an embodiment of the present invention, the second ECU may further include: a fourth current supply unit for selectively supplying current from the second current supply unit to the third motor, and a fourth selection unit for controlling the supply of battery power to the fourth current supply unit.

[0025] In an embodiment of the present invention, the first ECU may further include: a fifth current supply unit, which supplies current to the third motor when the first current supply unit is malfunctioning.

[0026] In an embodiment of the present invention, the second ECU may further include a sixth current supply unit, which supplies current to the third motor when the second current supply unit is malfunctioning.

[0027] Invention Effects

[0028] This invention configures multiple motor drive circuits. When one component malfunctions, the motor is driven by another drive circuit, thus improving the reliability of the electronic parking brake system.

[0029] In addition, the present invention uses multiple ECUs to drive the motor of the electronic parking brake system, and by using redundant ECUs to drive and control other motors, it has the effect of improving system efficiency. Attached Figure Description

[0030] Figure 1 This is a structural block diagram of the braking device using the present invention.

[0031] Figure 2 This is a structural block diagram of a motor drive circuit according to a preferred embodiment of the present invention.

[0032] Figure 3 This is a structural block diagram of a motor drive circuit according to another embodiment of the present invention. Detailed Implementation

[0033] Hereinafter, with reference to the accompanying drawings, the motor drive circuit of the electronic parking brake system of the present invention will be described in detail.

[0034] The embodiments of the present invention are provided to illustrate the invention more fully to those skilled in the art. The embodiments described below can be modified in various different forms, and the scope of the present invention is not limited to the following embodiments. Rather, these embodiments are provided to make the present invention more comprehensive and complete, and to fully convey the spirit of the present invention to those skilled in the art.

[0035] The terminology used in this specification is for illustrating specific embodiments and is not intended to limit the invention. As used herein, the singular form may include the plural form unless the context clearly indicates otherwise. Furthermore, when used herein, "comprising" and / or "including" designates the presence of the mentioned shapes, numbers, steps, actions, components, elements, and / or combinations thereof, and does not exclude the presence or addition of more than one other shape, number, step, action, component, element, and / or combination thereof. As used herein, the term "and / or" includes any one or more of the listed items and all combinations thereof.

[0036] Although the terms "first," "second," etc., are used in this specification to describe various components, regions, and / or parts, it is clear that these components, components, regions, layers, and / or parts are not limited to these terms. These terms do not imply a specific order, hierarchy, or superiority, but are only used to distinguish one component, region, or part from another. Therefore, without departing from the teachings of this invention, the following "first component, region, or part" may refer to a "second component, region, or part."

[0037] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings, which schematically illustrate embodiments of the invention. In the drawings, for example, variations in shape may be expected based on manufacturing techniques and / or tolerances. Therefore, embodiments of the present invention should not be construed as limited to specific shapes within the areas shown in this specification, but should include shape variations such as those caused by manufacturing processes.

[0038] Figure 1 This is a diagram illustrating the schematic structure of an electronic parking brake system according to an embodiment of the present invention.

[0039] Reference Figure 1The electronic parking brake system mainly includes: a brake pedal; wheels 101, 103, 105, and 107; brake calipers 102, 104, 106, and 108 that apply braking force to each wheel 101, 103, 105, and 107; wheel speed sensors (WSS) 101, 103, 105, and 107 that detect the rotational speed of each wheel 101, 103, 105, and 107; a parking positioning system (PTS) 129; motors 111 and 112 for controlling the drive of the parking brake, which is configured to be electronically operated by external force on the rear wheels 105 and 107 of the vehicle; and a braking device 200.

[0040] First wheels 101 and 103 are formed at the front of the vehicle. First brake calipers 102 and 104 are formed on first wheels 101 and 103, respectively. When an external force is applied to the brake pedal, first brake calipers 102 and 104 apply braking force to each wheel 101 and 103. Third wheels 105 and 107 are formed at the rear of the vehicle. Fourth brake calipers 108 of third brake calipers 106 are formed on third wheels 105 and 107, respectively. When an external force is applied to the brake pedal, fourth brake calipers 108 of third brake calipers 106 apply braking force to each wheel 105 and 107. Simultaneously, first motors 111 and 112 are formed. When an external force is applied to the Electronic Parking Brake (EPB) switch, first motors 111 and 112 control the drive of wheels 105 and 107 by actuating the electronically operated parking brake. The third motor 113 is a pedal-hiding motor, which operates when the pedal is hidden in autonomous driving mode.

[0041] Additionally, WSS 121, 123, 125, and 127 confirm the wheel rotation speed and provide it to the braking device 200, while PTS 129 is a pedal sensor that senses the external force generated on the brake pedal from outside the vehicle and provides it to the braking device 200. Based on the signal provided from PTS 129, the braking device 200 actuates brake calipers 102, 104, 106, and 108, thereby applying braking force to each wheel 101, 103, 105, and 107.

[0042] Figure 2 This is a structural block diagram of a motor drive circuit according to a preferred embodiment of the present invention.

[0043] Reference Figure 2 This invention can be referred to Figure 1The structure of the ECU block inside the braking device 200 includes: a first motor 111 and a second motor 112, which respectively release or activate the parking brakes of the left rear wheel and the right rear wheel; and a first ECU 10 and a second ECU 20, which respectively drive and control the first motor 111 and the second motor 112. When the first ECU 10 drives the first motor 111 and the second motor 112, the second ECU 20 does not intervene in driving the first motor 111 and the second motor 112. The second ECU 20 only drives and controls the first motor 111 and the second motor 112 when the first ECU 10 is malfunctioning.

[0044] Furthermore, when the first ECU 10 is driving the first motor 111 and the second motor 112, the idle second ECU 20 can drive the third motor 113. Conversely, when the second ECU 20 is driving the first motor 111 and the second motor 112, the idle first ECU 10 can drive the third motor 113. (See reference...) Figure 1 The third motor 113 may be a pedal hidden motor.

[0045] The first ECU 10 includes: a first MCU 11 for confirming the release or activation conditions of the electronic parking brake; a first drive unit 12 for switching control signals according to the control output of the first MCU 11; a first current supply unit 13 and a second current supply unit 14 for switching according to the switching control signal of the first drive unit 12 to change the direction of the current and supply it to each of the first motor 111 and the second motor 112; a first selection unit 15 for selectively blocking the supply of current from the first current supply unit 13 and the second current supply unit 14 to the first motor 20 and the second motor 112; and a third selection unit 16 for selectively supplying current from the first current supply unit 13 or the second current supply unit 14 to the third motor 113.

[0046] The second ECU 20 is a redundant circuit that is basically the same as the first ECU 10, and includes a second MCU 21, a second drive unit 22, a third current supply unit 23, a fourth current supply unit 24, a second selection unit 25, and a fourth selection unit 26.

[0047] The first selection unit 15 and the second selection unit 25 each include a switching element that switches according to the control signal of the upper controller.

[0048] The first selection unit 15 opens or closes the current supply line connecting the first current supply unit 13 and the first motor 111, as well as the current supply line connecting the second current supply unit 14 and the second motor 112.

[0049] Similarly, the second selection unit 25 also turns on or off the current supply line connecting the third current supply unit 23 and the first motor 111, as well as the current supply line connecting the fourth current supply unit 24 and the second motor 112.

[0050] In addition, although Figure 2 The diagram shows that the third selection unit 16 turns the current supply line on or off so as to selectively control the current supplied to the third motor 113 by the first current supply unit 13, but selectively supplies the current to the third motor 113 by the second current supply unit 14.

[0051] Similarly, the fourth selection unit 26 can selectively control the current supplied to the third current supply unit 23 or the fourth current supply unit 24 to the third motor 113.

[0052] With this configuration, the ECU that drives and controls the first motor 111 and the second motor 112 can be selected by using the first selection unit 15 and the second selection unit 25.

[0053] If there is an abnormality in the first MCU 11, the first drive unit 12, the first current supply unit 13, or the second current supply unit 14 constituting the first ECU 10, the upper-level controller (not shown) disconnects all the switching elements of the first selection unit 15 and connects all the switching elements of the second selection unit 25, thereby connecting the third current supply unit 23 and the first motor 111, and simultaneously connecting the fourth current supply unit 24 and the second motor 112. Therefore, the first motor 111 and the second motor 112 can be driven and controlled by the second ECU 20.

[0054] With this configuration, when one of the first ECU 10 and the second ECU 20 malfunctions, the other ECU, which is functioning correctly, can be used to drive and control the first motor 111 and the second motor 112, thus improving reliability.

[0055] In addition, when both the first ECU 10 and the second ECU 20 are operating normally, there are idle ECUs in addition to the ECUs that drive the first motor 111 and the second motor 112. At this time, the third motor 113 can be driven and controlled by the idle ECUs, thereby improving the efficiency of the circuit.

[0056] Figure 3 This is a structural block diagram of the motor drive circuit of an electronic parking brake system according to another embodiment of the present invention.

[0057] exist Figure 3 The image shows other structures of the first selection section 15 and the second selection section 25.

[0058] In the above example, the first selection unit 15 and the second selection unit 25 are respectively described as turning off or on the current supply line that supplies current to the first motor 111 and the second motor 112. When the current supply line is in the off state, the first selection unit 15 and the second selection unit 25 have a switching circuit structure for supplying or blocking the battery power supplied to the first current supply unit 13 and the second current supply unit 14, the third current supply unit 23 and the fourth current supply unit 24 respectively.

[0059] The first current supply unit 13, the second current supply unit 14, the third current supply unit 23, and the fourth current supply unit 24 are H-bridge structures comprising two transistors connected in parallel between the battery and ground, respectively. The current direction of the battery power supply BAT is changed according to the on and off state of each transistor and supplied to the first motor 111 and the second motor 112.

[0060] The first selection unit 15 controls the supply of battery power BAT to the first current supply unit 13 and the second current supply unit 14, and the second selection unit 25 controls the supply of battery power BAT to the third current supply unit 23 and the fourth current supply unit 24.

[0061] Therefore, when the first motor 111 and the second motor 112 are driven by the first ECU 10, the first selection unit 15 supplies battery power BAT to the first current supply unit 13 and the second current supply unit 14, and the second selection unit 25 blocks the supply of battery power BAT to the third current supply unit 23 and the fourth current supply unit 24, so that the second ECU 20 will not affect the driving of the first motor 111 and the second motor 112.

[0062] When the first ECU 10 malfunctions, the first selection unit 15 blocks the supply of battery power BAT to the first current supply unit 13 and the second current supply unit 14, and the second selection unit 25 supplies battery power BAT to the third current supply unit 23 and the fourth current supply unit 24, so that the first motor 111 and the second motor 112 can be driven by the second ECU 20.

[0063] In order to drive the third motor 113 independently, the first ECU 10 and the second ECU 20 also include a fifth current supply unit 17 and a sixth current supply unit 27, respectively.

[0064] At this time, the third selection unit 16 can supply or block the battery power supply BAT as the power source for the fifth current supply unit 17, and the fourth selection unit 26 controls the supply of battery power supply BAT to the sixth current supply unit 27.

[0065] exist Figure 3In the example, when the first motor 111 and the second motor 112 are driven by the first ECU 10, the second ECU 20 can drive the third motor 113. Conversely, when the first motor 111 and the second motor 112 are driven by the second ECU 20, the first ECU 10 can drive and control the third motor 113.

[0066] Figure 3 The feature is that the first ECU 10 and the second ECU 20 respectively include a fifth current supply unit 17 and a sixth current supply unit 27 as current supply units for driving the third motor 113. Even if there is an abnormality in the first current supply unit 13 or the second current supply unit 14, the fifth current supply unit 17 can be used to drive the third motor 113.

[0067] As described above, when the first current supply unit 13 malfunctions, the first ECU 10 is not used to control the first motor 111 and the second motor 112, but the first motor 111 and the second motor 112 can be driven by the second ECU 20, which is a redundant structure.

[0068] At this time, Figure 2 In the example shown, the configuration of the third motor 113 is difficult, but in a structure that includes the fifth current supply unit 17 and the third selection unit 16 that supplies battery power to the fifth current supply unit 17, the third motor 113 can be driven by the first ECU 10 which has an abnormality.

[0069] This invention is not limited to the above embodiments. Those skilled in the art should understand that various modifications and variations can be made without departing from the technical spirit of this invention.

[0070] 10: First ECU

[0071] 11: First MCU

[0072] 12: First Drive Unit

[0073] 13: First Current Supply Section

[0074] 14: Second Current Supply Section

[0075] 15: First Choice Department

[0076] 16: Third Choice Section

[0077] 20: Second ECU

[0078] 21: Second MCU

[0079] 22: Second drive unit

[0080] 23: Third Current Supply Section

[0081] 24: Fourth Current Supply Unit

[0082] 25: Second Choice Section

[0083] 26: Fourth Choice Section

[0084] 111: First Motor

[0085] 112: Second motor

[0086] 113: The third motor.

Claims

1. A motor drive circuit, characterized in that, include: The first and second motors release or activate the electronic parking brakes applied to different wheels, respectively. The first electronic control unit and the second electronic control unit respectively drive and control the first motor and the second motor; The second electronic control unit, When the first electronic control unit is driving the first motor and the second motor, it does not intervene in driving the first motor and the second motor; it only drives and controls the first motor and the second motor when there is an abnormality in the first electronic control unit. The first electronic control unit includes: The first microcontroller unit confirms the release or activation conditions of the electronic parking brake. The first drive unit switches control signals according to the control output of the first microcontroller unit. The first current supply unit switches according to the switching control signal of the first drive unit to change the direction of the current and supply it to each of the first motor and the second motor. The first selection unit selectively supplies current from the first current supply unit to the first motor and the second motor.

2. The motor drive circuit according to claim 1, characterized in that, The second electronic control unit includes: The second microcontroller unit confirms the release or activation conditions of the electronic parking brake. The second drive unit switches control signals according to the control output of the second microcontroller unit. The second current supply unit switches according to the switching control signal of the second drive unit to change the direction of the current and supply it to each of the first motor and the second motor. The second selection unit selectively supplies current from the second current supply unit to the first motor and the second motor.

3. The motor drive circuit according to claim 1, characterized in that, The first selection unit controls the current supplied to the battery by the first current supply unit.

4. The motor drive circuit according to claim 3, characterized in that, The second electronic control unit includes: The second microcontroller unit confirms the release or activation conditions of the electronic parking brake. The second drive unit switches control signals according to the control output of the second microcontroller unit. The second current supply unit switches according to the switching control signal of the second drive unit to change the direction of the current and supply it to each of the first motor and the second motor. The second selection unit controls the current supplied to the battery by the second current supply unit.

5. A motor drive circuit, characterized in that, include: The first and second motors release or activate the electronic parking brakes applied to different wheels, respectively. The first electronic control unit and the second electronic control unit respectively drive and control the first motor and the second motor; The second electronic control unit, When the first electronic control unit is driving the first motor and the second motor, it does not intervene in driving the first motor and the second motor. It only drives and controls the first motor and the second motor when the first electronic control unit malfunctions. Furthermore, when the first electronic control unit is driving the first motor and the second motor, it drives and controls the third motor. The first electronic control unit includes: The first microcontroller unit confirms the release or activation conditions of the electronic parking brake. The first drive unit switches control signals according to the control output of the first microcontroller unit. The first current supply unit switches according to the switching control signal of the first drive unit to change the direction of the current and supply it to each of the first motor and the second motor. The first selection unit selectively supplies current from the first current supply unit to the first motor and the second motor.

6. The motor drive circuit according to claim 5, characterized in that, The second electronic control unit includes: The second microcontroller unit confirms the release or activation conditions of the electronic parking brake. The second drive unit switches control signals according to the control output of the second microcontroller unit. The second current supply unit switches according to the switching control signal of the second drive unit to change the direction of the current and supply it to each of the first motor and the second motor. The second selection unit selectively supplies current from the second current supply unit to the first motor and the second motor.

7. The motor drive circuit according to claim 5, characterized in that, The first selection unit controls the current supplied to the battery by the first current supply unit.

8. The motor drive circuit according to claim 7, characterized in that, The second electronic control unit includes: The second microcontroller unit confirms the release or activation conditions of the electronic parking brake. The second drive unit switches control signals according to the control output of the second microcontroller unit. The second current supply unit switches according to the switching control signal of the second drive unit to change the direction of the current and supply it to each of the first motor and the second motor. The second selection unit controls the current supplied to the battery by the second current supply unit.

9. The motor drive circuit according to claim 6 or 8, characterized in that, The first electronic control unit further includes: The third current supply unit is used to selectively supply the current from the first current supply unit to the third motor, and The third selection unit controls the supply of battery power to the third current supply unit.

10. The motor drive circuit according to claim 9, characterized in that, The second electronic control unit further includes: The fourth current supply unit is used to selectively supply the current from the second current supply unit to the third motor, and The fourth selection unit controls the supply of battery power to the fourth current supply unit.

11. The motor drive circuit according to claim 10, characterized in that, The first electronic control unit further includes: The fifth current supply unit supplies current to the third motor when the first current supply unit malfunctions.

12. The motor drive circuit according to claim 11, characterized in that, The second electronic control unit further includes: The sixth current supply unit supplies current to the third motor when the second current supply unit malfunctions.

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