Electric parking brake control device

Abstract

Disclosed is an electric parking brake control device capable of accurately determining the operation of an electric actuator. The electric parking brake control device is capable of performing a force application process and a release process. The force application process is a process of controlling the electric actuator to move a friction member in a pressing direction with respect to a rotating body that rotates integrally with a wheel. The release process is a process of controlling the electric actuator to move the friction member in a direction away from the rotating body. The electric parking brake control device does not perform a change in the operation of the electric actuator based on a new operation request for operating the electric actuator (time t12) even if the new operation request is received during a period from the start to the completion of the force application process or the release process (times t1 to t5).

Description

Technical Field

[0001] This disclosure relates to an electric parking brake control device that controls an electric actuator to move a friction component relative to a rotating body that rotates integrally with the wheel in a pressing direction and a disengaging direction. Background Technology

[0002] Conventionally, as a control device for an electric parking brake, there are known devices capable of performing force application and release operations. Force application refers to controlling the electric actuator to move the pad, which is a friction component, relative to the rotor, which is a rotating body, in a pressing direction. Release operation refers to controlling the electric actuator to move the pad in a direction separating from the rotor (see Japanese Patent No. 6466473). Specifically, in this technology, if the electric parking brake control device receives a request for release operation before the pad and rotor come into contact during the execution of force application, it will not perform release operation until the pad and rotor come into contact, and will perform release operation after the pad and rotor come into contact.

[0003] In addition, during the release process, if the electric parking brake control device receives a request for force application before the pad separates from the rotor, it will not perform force application until the pad and rotor separate, and will perform force application after the pad and rotor separate. Summary of the Invention

[0004] In the prior art, even after the liner and rotor have come into contact or separated, the process may be stopped midway and different processes may be performed before the force application or release process is completed. Therefore, it may be impossible to accurately determine the action of the electric actuator.

[0005] The aim is to provide an electric parking brake control device that can accurately determine the action of the electric actuator.

[0006] In view of the above background, an electric parking brake control device is disclosed, which is capable of performing force application and release processing. The force application refers to controlling an electric actuator to move a friction member in a pressing direction relative to a rotating body that rotates integrally with the wheel. The release processing refers to controlling the electric actuator to move the friction member in a direction that separates it from the rotating body.

[0007] Even if a new operating request for the electric actuator is received during the period from the start of the force application process or the release process to the completion of the process, the electric parking brake control device will not perform any action change of the electric actuator based on the operating request.

[0008] According to this structure, since the electric actuator's action change based on the new work request is not performed even if a new work request is received during the period from the start of the force application process or the release process to the completion of the process, the action determination of the electric actuator can be accurately performed.

[0009] Alternatively, the electric parking brake control device may, during the period from the start of the force application process or the release process to the completion of the process, if a new work request is received for performing a process different from the currently performed process, then after the current process is completed, the process based on the new work request is executed.

[0010] According to this structure, since a work requirement is made during the execution of the force application or release process to perform a process different from the currently being executed process, the process based on the new work requirement is executed after the currently being executed process is completed, thus enabling a rapid response to the user's request.

[0011] Alternatively, the electric parking brake control device may be configured such that, during the period from the start of the force application process or the release process to the completion of the process, if a new work request is received to perform the same process as the currently being performed, the process based on the new work request is not performed after the current process is completed.

[0012] According to this structure, since during the execution of force application or release processing, if a work requirement is made to perform the same process as the currently being executed process, a process based on a new work requirement is not executed after the currently being executed process is completed, thus preventing the repeated execution of the same process.

[0013] Alternatively, the electric parking brake control device may be configured to control the electric actuator based on the last received work request among the multiple new work requests received during the period from the start of the force application process or the release process to the completion of the process.

[0014] According to this structure, since the electric actuator is controlled based on the last received work request among multiple new work requests received during the execution of force application or release processing, it is possible to control the electric actuator in accordance with the user's intention. Attached Figure Description

[0015] Figure 1 This is a configuration diagram of a vehicle equipped with an electric parking brake control device according to one embodiment.

[0016] Figure 2The diagrams show drum brakes and parking brake mechanisms. (a) shows the state where no braking is applied, and (b) shows the state where braking is applied using the parking brake mechanism.

[0017] Figure 3 This is a cross-sectional view showing the electric actuator of the parking brake mechanism.

[0018] Figure 4 This is a flowchart illustrating the processing of the control unit.

[0019] Figure 5 This is a flowchart illustrating the process of applying force.

[0020] Figure 6 This is a flowchart representing the process of handling a release request.

[0021] Figure 7 This is a timing diagram illustrating an example of the control unit's actions when a new work request received during force application is a requirement for force application.

[0022] Figure 8 This is a timing diagram illustrating an example of the control unit's actions when a new work request received during the force application process becomes a release process request.

[0023] Figure 9 This is a timing diagram illustrating an example of the control unit's actions when a new work request received during the release process is a requirement for the release process.

[0024] Figure 10 This is a timing diagram illustrating an example of the control unit's actions when a new work request received during the release process is a force application request. Detailed Implementation

[0025] One embodiment of the electric parking brake control device will be described in detail with appropriate reference to the accompanying drawings.

[0026] like Figure 1 As shown, the vehicle CR is equipped with a drum brake D, a parking brake mechanism 200, and a vehicle brake hydraulic control device 100.

[0027] Drum brakes D are respectively installed on the four wheels W. The parking brake mechanism 200 is a mechanism that mechanically actuates the drum brakes D, and is provided for the drum brakes D installed on the two rear wheels W.

[0028] The vehicle brake hydraulic control device 100 is used to appropriately control the braking force applied to each wheel W of the vehicle CR. The vehicle brake hydraulic control device 100 mainly includes a hydraulic unit 10 equipped with oil circuits (hydraulic circuits) and various components, and a control unit 20 for appropriately controlling the various components within the hydraulic unit 10. The hydraulic unit 10 is connected via oil circuits to the master cylinder MC, which generates brake hydraulic pressure when the brake pedal BP is depressed, and also via oil circuits to the wheel cylinders D4 of each drum brake D. The hydraulic unit 10 includes valves, pumps, etc., for controlling the brake hydraulic pressure applied to the wheel cylinders D4.

[0029] The control unit 20 is an example of an electric parking brake control device. In addition to controlling the driving and stopping of the electric actuator 240 that actuates the parking brake mechanism 200, the control unit 20 also controls the valves and pumps within the hydraulic unit 10. A wheel speed sensor 91 and a parking switch 92 are connected to the control unit 20. The wheel speed sensor 91 detects the wheel speed of wheel W. The parking switch 92 is used to switch the state of the parking brake mechanism 200 between a force-applied state and a release state. Here, the force-applied state refers to the state in which the parking brake mechanism 200 generates braking force. The release state refers to the state in which the parking brake mechanism 200 releases the braking force.

[0030] The parking switch 92 can be switched between a force application position and a release position. When the parking switch 92 is in the force application position, it outputs a force application signal to the control unit 20 to enable the parking brake mechanism 200 to be in a force application state, and when it is in the release position, it outputs a release signal to the control unit 20 to enable the parking brake mechanism 200 to be in a release state.

[0031] The control unit 20 includes, for example, a CPU, RAM, ROM, and input / output circuits. It performs various calculations and processing based on inputs from the wheel speed sensor 91, parking switch 92, etc., and programs and data stored in the ROM to perform control.

[0032] like Figure 2 As shown in (a) and (b), the drum brake D includes a drum D1 as an example of a rotating body, a brake pad D2 as an example of a friction component, a return spring D3, and a wheel cylinder D4. The drum D1 is a component having a cylindrical portion that rotates integrally with the wheel W.

[0033] Brake pad D2 is an arc-shaped component extending along the inner circumferential surface of drum D1, which applies braking force to wheel W by pressing against the inner circumferential surface of drum D1. Two brake pads D2 are provided along the inner circumferential surface of drum D1. Each of the two brake pads D2 has one end rotatably supported by a support member D5, thereby allowing them to rotate in directions toward each other and in directions apart.

[0034] The return spring D3 applies force to the other ends of the two brake pads D2 in a direction that brings them closer together. The wheel cylinder D4 uses the brake hydraulic pressure supplied from the hydraulic unit 10 to apply force to the inner circumferential surface of the two brake pads D2 against the drum D1.

[0035] The parking brake mechanism 200 includes a support rod 210, a parking lever 220, a cable 230, and Figure 3 The electric actuator 240 is shown. The strut 210 engages with the other end of each of the two brake pads D2.

[0036] One end of the parking lever 220 is rotatably supported by a pin 221 on a brake pad D2. A cable 230 is connected to the other end of the parking lever 220. The portion of the parking lever 220 between one end and the other end, and closer to one end, engages with a support rod 210.

[0037] If cable 230 is pulled to the right as shown in the diagram, parking lever 220 rotates around pin 221, thereby pressing brake pad D2 against the inner circumferential surface of drum D1 via support rod 210. Furthermore, if cable 230 is pulled, parking lever 220 rotates around its engagement point with support rod 210, thereby pressing brake pad D2 against the inner circumferential surface of drum D1 via pin 221.

[0038] Thus, through the pulling action of the wire 230, each brake pad D2 is pressed against the inner circumferential surface of the drum D1. Furthermore, if the wire 230 is released to the left in the diagram, each brake pad D2 separates from the inner circumferential surface of the drum D1 by the force of the return spring D3.

[0039] like Figure 3 As shown, the electric actuator 240 is a device for traction of the line 230. The electric actuator 240 includes a motor 241, multiple gears 242, a nut 243, a lead screw shaft 244, a housing 245, a cage 246, and multiple disc springs 247.

[0040] Nut 243 is connected to motor 241 via multiple gears 242. Nut 243 has an internal thread 243A that engages with the external thread 244A of lead screw shaft 244. Lead screw shaft 244 is supported on housing 245 in a manner that allows axial movement, and a wire 230 is fixed to its front end. At the end of lead screw shaft 244 opposite to the front end, a radially protruding flange 244B is formed.

[0041] The retainer 246 is a circular plate component with a central hole, which engages with the flange 244B of the lead screw 244 from the front end side of the lead screw 244. A plurality of disc springs 247 are arranged axially between the flange 244B and the nut 243 of the lead screw 244.

[0042] In the electric actuator 240, if the motor 241 is rotated forward, the lead screw 244 moves towards the housing 245, thereby pulling the cable 230 and putting the parking brake mechanism 200 into a force-applied state where the parking brake is engaged. Conversely, if the motor 241 is rotated in reverse, the lead screw 244 moves towards protruding from the housing 245, thereby releasing the cable 230 and putting the parking brake mechanism 200 into a released state where the parking brake is disengaged. Furthermore, in the released state, multiple disc springs 247 are held in a deformed state between the retainer 246 and the nut 243.

[0043] In the following description, the position of the lead screw shaft 244 when the parking brake mechanism 200 is in the applied state is also referred to as the "applied state," and the position of the lead screw shaft 244 when the parking brake mechanism 200 is in the released state is also referred to as the "release state." Specifically, the release state is... Figure 3 The position shown indicates the location where force is applied. Figure 3 The lead screw shaft 244 shown has been moved to the right of the position shown in the figure.

[0044] The control unit 20 controls the forward rotation, reverse rotation, and stop of the motor 241 based on the signal from the parking switch 92. The control unit 20 has the function of performing force application processing and release processing. In the following description, the output of the force application signal from the parking switch 92 is also referred to as the "force application processing requirement", and the output of the release signal from the parking switch 92 is also referred to as the "release processing requirement". These processing requirements are collectively referred to as "operating requirements".

[0045] The force application process is the process of driving the electric actuator 240 to put the parking brake mechanism 200 into a force-applied state. In other words, the force application process is the process of controlling the electric actuator 240 to move the brake pad D2 relative to the drum D1 in the pressing direction. Specifically, if the control unit 20 receives a request for force application, it causes the motor 241 to rotate forward, thereby moving the lead screw shaft 244 to the force-applied position, thus putting the parking brake mechanism 200 into a force-applied state.

[0046] In detail, such as Figure 7 As shown, if the control unit 20 receives a request for force application (A), it begins force application by supplying current to the motor 241 to make it rotate forward (time t1). When the motor 241 is energized, an inrush current is generated, but the inrush current converges after a predetermined time (time t2). If the inrush current converges, the motor 241 begins to rotate.

[0047] Therefore, the lead screw shaft 244 begins to move from the released position to the applied position. As the lead screw shaft 244 moves from the released position to the applied position, the load applied to the lead screw shaft 244 by the disc spring 247 gradually decreases, and thus the current gradually decreases. If the lead screw shaft 244 separates from the cage 246, no longer a load is applied to the lead screw shaft 244 (at time t3), after which the current becomes constant.

[0048] Subsequently, if brake pad D2 contacts drum D1 (time t4), the load applied to lead screw shaft 244 gradually increases, and the current supplied to motor 241 rises. Subsequently, if the current becomes higher than the force application threshold IA (time t5), the control unit 20 stops energizing, completing the force application process.

[0049] The release process is the process of driving the electric actuator 240 to put the parking brake mechanism 200 into the released state. In other words, the release process is the process of controlling the electric actuator 240 to move the brake pad D2 in the direction of separation from the drum D1. Specifically, if the control unit 20 receives a request for a release process, it reverses the motor 241 to move the lead screw 244 to the release position, thereby releasing the parking brake mechanism 200.

[0050] In detail, such as Figure 9 As shown, if the control unit 20 receives a release processing request (R), it initiates the release processing by supplying current to the motor 241 to reverse the motor 241 (time t51). When the motor 241 is energized, an inrush current is generated, but the inrush current converges after a predetermined time (time t52). If the inrush current converges, the motor 241 begins to rotate.

[0051] Therefore, the lead screw shaft 244 moves from the applied force position to the released position, and the brake pad D2 moves in the direction of separation from the drum D1. As the lead screw shaft 244 moves from the applied force position to the released position, the load applied to the lead screw shaft 244 by the brake pad D2 gradually decreases, and the current gradually decreases. If the brake pad D2 separates from the drum D1, no more load is applied to the lead screw shaft 244 (at time t53), after which the current becomes constant.

[0052] Subsequently, if the lead screw shaft 244 contacts the cage 246 (at time t54), the load applied to the lead screw shaft 244 by the disc spring 247 gradually increases, and the current supplied to the motor 241 rises. Subsequently, if the current becomes above the release threshold IR (at time t55), the control unit 20 stops energizing, completing the release process.

[0053] The control unit 20 is configured such that, during the period from the start of the force application or release process to the completion of the process, even if a new work request for operating the electric actuator 240 is received, no change to the operation of the electric actuator 240 based on that work request is executed. Furthermore, the control unit 20 is configured such that, during the period from the start of the force application or release process to the completion of the process, if a new work request is received for performing a process different from the currently being performed, the process based on the new work request is executed after the current process is completed (see reference). Figure 8 and Figure 10 ).

[0054] Furthermore, the control unit 20 is configured such that, during the period from the start of the force application process or the release process to the completion of the process, if a new work request is received for performing the same process as the currently being performed, the process based on the new work request will not be performed after the current process is completed (see reference). Figure 7 and Figure 9 Furthermore, the control unit 20 is configured to control the electric actuator 240 based on the last received work request among the multiple new work requests received during the period from the start of the force application process or the release process to the completion of the process.

[0055] Next, refer to Figures 4-6 The processing of the control unit 20 is explained in detail. The control unit 20 continuously executes... Figure 4 The processing shown.

[0056] exist Figure 4 In the process, the control unit 20 first determines whether there is a working requirement for operating the electric actuator 240 (S1). If it is determined in step S1 that there is no working requirement (No), the control unit 20 ends the process.

[0057] If a work requirement is determined to exist in step S1 (Yes), the control unit 20 determines whether the work requirement is a force application requirement (S2). If it is determined to be a force application requirement in step S2 (Yes), the control unit 20 executes the force application requirement processing (S3). Here, the force application requirement processing refers to the process performed when a force application requirement is received. Figure 5 The processing shown will be described in detail later.

[0058] If, in step S2, it is determined that the request is not for force application (No), the control unit 20 executes the release request processing (S4). Here, the release request processing refers to the process performed when a release request is received. Figure 6 The process shown will be described in detail later. After step S3 or step S4, the control unit 20 ends this process.

[0059] like Figure 5 As shown, in the force application request processing, after executing the force application processing shown in steps S11 to S15, the control unit 20 executes the processing shown in steps S16 to S18, which controls the electric actuator 240 based on the new work request received in the force application processing. Specifically, in the force application request processing, the control unit 20 first starts energizing for the force application processing (S11). In detail, in step S11, the control unit 20 supplies current to the motor 241 to make the motor 241 rotate forward.

[0060] After step S11, the control unit 20 determines whether there is a new work requirement (S12). If it is determined in step S12 that there is a new work requirement (yes), the control unit 20 stores the new work requirement (S13).

[0061] After step S13, or if it is determined in step S12 that there are no new work requirements (No), the control unit 20 determines that a first time T1 has elapsed since the start of the force application process (refer to...). Figure 7 The control unit 20 determines in step S14 whether the current after the force application process is greater than or equal to the force application threshold IA. Specifically, the control unit 20 determines whether the conditions of a first time T1 having elapsed since the start of the force application process and the current being greater than or equal to the force application threshold IA are simultaneously met. Here, the first time T1 is the time from the start of the force application process until the current becomes sufficiently smaller than the force application threshold IA after the initial impact current converges. This time is appropriately set through experiments, simulations, etc.

[0062] If in step S14 it is determined that the current after the first time T1 is not above the force application threshold IA (No), the control unit 20 returns to the processing in step S12. If in step S14 it is determined that the current after the first time T1 is above the force application threshold IA (Yes), the control unit 20 cuts off the power supply and completes the force application process (S15).

[0063] After step S15, the control unit 20 determines whether there is a new work requirement in the force application process completed this time (S16). If it is determined in step S16 that there is a new work requirement (yes), the control unit 20 determines whether the new work requirement is a requirement for the release process (S17). Specifically, if the control unit 20 receives one new work requirement in the force application process, it determines whether the work requirement is a requirement for the release process (S17).

[0064] If, in step S17, the new work requirement is determined to be a release procedure (Yes), the control unit 20 executes the release requirement processing (S18) and terminates the current process. Conversely, if, in step S16 or S17, the requirement is not met, the control unit 20 terminates the current process directly. Therefore, if, in step S17, the new work requirement is a force application procedure, the control unit 20 does not execute the force application procedure and terminates the current process.

[0065] In addition, if the control unit 20 receives multiple work requests during the force application process, it determines whether the last work request received among the multiple new work requests is a release process request (S17).

[0066] Furthermore, any method can be used to determine the last received work request from multiple new work requests. For example, in step S13, multiple new work requests and the times at which they were received can be stored correspondingly, and the last received work request can be determined based on the times. Alternatively, in step S13, the last received work request can be determined by overwriting previously stored new work requests with new ones. Furthermore, the stored new work requests can be reset, for example, at the start of the force application process or the start of the release process.

[0067] like Figure 6 As shown, in the release request processing, after executing the release processing shown in steps S31 to S35, the control unit 20 executes the processing shown in steps S36 to S38, which controls the electric actuator 240 based on the new working request received during the release processing. Specifically, in the release request processing, the control unit 20 first starts energizing for the release processing (S31). In detail, in step S31, the control unit 20 supplies current to the motor 241 to reverse the motor 241.

[0068] After step S31, the control unit 20 determines whether there is a new work requirement (S32). If it is determined in step S32 that there is a new work requirement (yes), the control unit 20 stores the new work requirement (S33).

[0069] After step S33, or if it is determined in step S32 that there are no new work requirements (No), the control unit 20 determines that a second time T2 has elapsed since the start of the release process (refer to...). Figure 9The control unit 20 determines in step S34 whether the current after the release process is above the release threshold IR. Specifically, the control unit 20 determines whether the conditions of a second time T2 elapsed since the start of the release process and the current being above the release threshold IR are simultaneously met. Here, the second time T2 is the time from the start of the release process until the current becomes sufficiently smaller than the release threshold IR after the initial surge current converges. This time is appropriately set through experiments, simulations, etc.

[0070] If, in step S34, it is determined that the current after the second time T2 is not above the release threshold IR (No), the control unit 20 returns to the processing in step S32. If, in step S34, it is determined that the current after the second time T2 is above the release threshold IR (Yes), the control unit 20 cuts off the power supply and completes the release process (S35).

[0071] After step S35, the control unit 20 determines whether there is a new work requirement in the completed release process (S36). If it is determined in step S36 that a new work requirement exists (yes), the control unit 20 determines whether the new work requirement is a force application requirement (S37). Specifically, if the control unit 20 receives one new work requirement in the release process, it determines whether the work requirement is a force application requirement (S37).

[0072] If, in step S37, the new work requirement is determined to be a force application requirement (Yes), the control unit 20 executes the force application requirement processing (S38) and ends the current process. Conversely, if, in step S36 or S37, the requirement is not met, the control unit 20 directly ends the current process. Therefore, if, in step S37, the new work requirement is a release requirement, the control unit 20 does not execute the release process and ends the current process.

[0073] In addition, if the control unit 20 receives multiple work requests during the release process, it determines whether the last work request received among the multiple new work requests is a request for force application (S37).

[0074] Furthermore, the method for determining the last received work requirement from multiple new work requirements, and the method for resetting the new work requirements, can be performed using the same method as when handling force requirements.

[0075] Next, refer to Figures 7-10 A detailed explanation of one example of the operation of the control unit 20 is provided.

[0076] like Figure 7As shown, if the control unit 20 receives a force application request (A), it begins force application processing (time t1). During force application processing (t1 to t5), as shown by the solid line in the figure, multiple new work requests are received. If the last received work request is a force application request (A) (time t11), the control unit 20 does not execute force application processing based on the new force application request (A) after the force application processing ends (time t5). Furthermore, during force application processing (t1 to t5), as shown by the double-dotted line in the figure, if only one force application request (A) is received as a new work request (time t12), the control unit 20 also does not execute force application processing based on the new force application request (A) after the force application processing ends (time t5).

[0077] like Figure 8 As shown, during the force application process (t1 to t5), as indicated by the solid line in the figure, multiple new work requests are received. If the last received work request is a release request (R) (time t21), the control unit 20 executes the release process (time t23) after the force application process ends (time t5). Furthermore, during the force application process (t1 to t5), as indicated by the double-dotted line in the figure, if only one release request (R) is received as a new work request (time t22), the control unit 20 also executes the release process (time t23) after the force application process ends (time t5).

[0078] like Figure 9 As shown, if the control unit 20 receives a release processing request (R), it begins the release processing (time t51). During the release processing (t51 to t55), as shown by the solid line in the figure, multiple new work requests are received. If the last work request received is a release processing request (R) (time t61), the control unit 20 does not execute the release processing based on the new release processing request (R) after the release processing ends (time t5). Furthermore, during the release processing (t51 to t55), as shown by the double-dotted line in the figure, if only one release processing request (R) is received as a new work request (time t62), the control unit 20 also does not execute the release processing based on the new release processing request (R) after the release processing ends (time t55).

[0079] like Figure 10As shown, during the release process (t51~t55), as indicated by the solid line in the figure, multiple new work requests are received. If the last received work request is a force application request (A) (time t71), the control unit 20 executes the force application process (time t73) after the release process ends (time t55). Furthermore, during the release process (t51~t55), as indicated by the double-dotted line in the figure, if only one force application request (A) is received as a new work request (time t72), the control unit 20 also executes the force application process (time t73) after the release process ends (time t55).

[0080] Based on the above, the following effects can be achieved in this embodiment.

[0081] During the period from the start of force application or release processing to the completion of processing, even if a new work request is received, the operation of the electric actuator 240 based on the work request is not changed, so the operation determination of the electric actuator 240 can be accurately performed.

[0082] During the execution of force application or release processing, if a work requirement is made to execute a process different from the currently executing process, the process based on the new work requirement is executed after the currently executing process is completed, thus enabling a rapid response to user requests.

[0083] According to this structure, during the execution of force application or release processing, if a work requirement is made to perform the same process as the currently being executed process, a process based on the new work requirement will not be executed after the currently being executed process is completed, thus preventing the repeated execution of the same process.

[0084] Since the electric actuator 240 is controlled based on the last received work request among multiple new work requests received during the execution of the force application or release process, the electric actuator 240 can be controlled in accordance with the user's intention.

[0085] Furthermore, the embodiments described herein can be modified in various ways as illustrated below.

[0086] In the described embodiment, the control unit 20 of the vehicle brake hydraulic control device 100 is exemplified as the electric parking brake control device, but a control device different from the vehicle brake hydraulic control device, such as the vehicle's ECU (Electronic Control Unit), may also be used as the electric parking brake control device.

[0087] In the described embodiment, a parking brake mechanism 200 provided on a drum brake D is exemplified, but it could also be a parking brake mechanism provided on a disc brake, for example. In this case, the rotor that rotates integrally with the wheel is equivalent to a rotating body, and the pad pressed against the rotor is equivalent to a friction member.

[0088] The elements described in the embodiments and variations can also be combined in any way.

Claims

1. An electric parking brake control device capable of performing force application and release operations, wherein the force application operation refers to controlling an electric actuator to move a friction member in a pressing direction relative to a rotating body that rotates integrally with the wheel, and the release operation refers to controlling the electric actuator to move the friction member in a direction of separation from the rotating body, characterized in that... During the period from the start of the force application process or the release process to the completion of the process, even if a new work request for operating the electric actuator is received, no change in the operation of the electric actuator based on the work request will be executed. If the work requirement is a requirement of the force application process, then the force application process begins based on the work requirement. If no new work request is received during the period from the start to the completion of the force application process, and the current after the specified time elapsed since the energization of the electric actuator and the convergence of the inrush current is above the force application threshold, the energization of the electric actuator will be cut off, thus completing the force application process. If a new work requirement is received during the period from the start of the force application process to its completion, the force application process continues until the current after the impact current converges is above the force application threshold, at which point the power supply to the electric actuator is cut off, and the force application process is completed.

2. The electric parking brake control device as described in claim 1, characterized in that, If a new work request for a release process is received during the period from the start of the force application process to its completion, a release process based on the new work request is executed after the force application process is completed.

3. The electric parking brake control device as described in claim 1, characterized in that, If a new work request for a force application is received during the period from the start of the force application process to its completion, the force application process based on the new work request will not be executed after the force application process is completed.

4. The electric parking brake control device as described in claim 2, characterized in that, If a new work request for a force application is received during the period from the start of the force application process to its completion, the force application process based on the new work request will not be executed after the force application process is completed.

5. The electric parking brake control device as described in any one of claims 2 to 4, characterized in that, During the period from the start of the force application process to its completion, if multiple new work requests are received, the electric actuator is controlled based on the last received work request among the multiple new work requests after the force application process is completed.

6. An electric parking brake control device capable of performing force application and release operations, wherein the force application operation refers to controlling an electric actuator to move a friction member in a pressing direction relative to a rotating body that rotates integrally with the wheel, and the release operation refers to controlling the electric actuator to move the friction member in a direction of separation from the rotating body, the electric parking brake control device being characterized in that… During the period from the start of the force application process or the release process to the completion of the process, even if a new work request for operating the electric actuator is received, no change in the operation of the electric actuator based on the work request will be executed. If the work requirement is a requirement of the release process, then the release process begins based on the work requirement. If no new work request is received during the period from the start of the release process to its completion, and the current after the specified time elapsed since energizing the electric actuator and the inrush current converges is above the release threshold, the energizing of the electric actuator will be cut off, thus completing the release process. If a new work request is received during the period from the start of the release process to its completion, the release process continues until the current after the impact current converges is above the release threshold, at which point the power to the electric actuator is cut off, and the release process is completed.

7. The electric parking brake control device as described in claim 6, characterized in that, If a new work request for force application is received during the period from the start of the release process to its completion, the force application process based on the new work request is executed after the release process is completed.

8. The electric parking brake control device as described in claim 6, characterized in that, If a new work request for a release process is received during the period from the start of the release process to its completion, the release process based on the new work request will not be executed after the release process is completed.

9. The electric parking brake control device as described in claim 7, characterized in that, If a new work request for a release process is received during the period from the start of the release process to its completion, the release process based on the new work request will not be executed after the release process is completed.

10. The electric parking brake control device as described in any one of claims 7 to 9, characterized in that, During the period from the start of the release process to its completion, if multiple new work requests are received, the electric actuator is controlled based on the last received work request among the multiple new work requests after the release process is completed.

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