JP2007045232A - Inspection method and inspection device of electric parking brake - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inspection method or the like capable of accurately evaluating performance of electric parking brake. <P>SOLUTION: The electric power brake is provided on the wheel of a vehicle and driven by an actuator. The inspection of the electric parking brake comprises a brake indication step S03 indicating the generation of a predetermined target braking force for the control part controlling the electric parking brake, a braking force detection step S04 detecting the actual braking force generated by the electric parking brake, and a braking force comparison step S12 comparing the target braking force to the actual braking force. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an apparatus and method for inspecting an electric parking brake provided in a vehicle such as an automobile and driven by an electric actuator.

The electric parking brake drives a parking brake that performs braking when the vehicle is parked or stopped using an electric actuator such as a motor.
Since such an electric parking brake can be operated by an electric switch by a driver, the labor is reduced with respect to an operation by a general manual lever or a foot pedal, and automatically operates according to the state of the vehicle. By doing so, it is possible to prevent the vehicle from starting to move unintended by the driver due to AT creep, slope inclination, etc., which contributes to the improvement of safety.
An electric parking brake is known that changes the braking force generated according to, for example, a manual operation of a driver (see, for example, Patent Document 1).
JP 2004-66874 A

The electric parking brake is different from a manual parking brake that can obtain a braking force according to the operation input by the driver, etc., and controls the actuator when the generated braking force is smaller than the braking force assumed at the time of design. Even if the control unit that performs the control to prevent the vehicle from moving normally may not be able to actually prevent the vehicle from moving, for example, the performance is accurately evaluated at the time of manufacturing or maintenance of the vehicle. It is requested.
An object of the present invention is to provide an inspection method and an inspection apparatus that can accurately evaluate the performance of an electric parking brake.

The present invention solves the above-described problems by the following means.
According to a first aspect of the present invention, there is provided a method for inspecting an electric parking brake provided on a wheel of a vehicle and driven by an actuator, wherein a brake that instructs generation of a predetermined target braking force to a control unit that controls the electric parking brake is provided. Electric parking comprising: an instruction step; a braking force detection step for detecting an actual braking force generated by the electric parking brake; and a braking force comparison step for comparing the target braking force with the actual braking force. This is a brake inspection method.
According to a second aspect of the present invention, in the method for inspecting an electric parking brake according to the first aspect, a braking time for comparing a time until the driving of the electric parking brake is completed after execution of the braking instruction step with a target braking time. An electric parking brake inspection method comprising an evaluation step.
According to a third aspect of the present invention, in the electric parking brake inspection method according to the first or second aspect, when the electric parking brake is in a braking state, the electric parking brake is released to the control unit. An electric parking brake inspection comprising: an instructing release instruction step; and a release time evaluation step of comparing a time until the electric parking brake is released after execution of the release instruction step with a target release time Is the method.

According to a fourth aspect of the present invention, there is provided an inspection device for an electric parking brake that is provided on a vehicle wheel and is driven by an actuator. The inspection device is connected to a control unit that controls the electric parking brake. A control signal output unit that outputs a power generation instruction, a braking force detection unit that detects a braking force generated by the electric parking brake, and an information processing unit that compares the target braking force and the output of the braking force detection unit And an electric parking brake inspection device.
According to a fifth aspect of the present invention, in the electric parking brake inspection device according to the fourth aspect, the information processing unit is configured to output the target braking force after the control signal output unit outputs an instruction to generate the target braking force. The electric parking brake inspection apparatus includes a function of comparing a braking time until the driving is completed with a target braking time.
According to a sixth aspect of the present invention, in the electric parking brake inspection device according to the fourth or fifth aspect, the control signal output unit outputs a release instruction for releasing the electric parking brake to the control unit. The information processing unit has a function of comparing a release time until the electric parking brake is released after the control signal output unit outputs the release instruction with a target release time. This is an inspection device for an electric parking brake.

According to the present invention, the actual braking force (actual braking force) is detected by instructing the target braking force to the control unit of the electric parking brake, and the actual braking force is compared with the target braking force. Parking brake performance can be evaluated quantitatively. As a result, it is possible to perform accurate evaluation by eliminating variations due to workers or the like.
In addition, the time required for the electric parking brake to generate the maximum braking force and the time required to release the braking force are detected and compared with the target braking time and the target releasing time, respectively. Can be evaluated.

  An object of the present invention is to provide an inspection method or the like that can accurately evaluate the performance of an electric parking brake. The electric parking brake is driven by instructing a predetermined target braking force, and the braking force detected by a brake tester is set as a target. Solved by comparing with braking force.

Embodiments of an inspection method and an inspection apparatus for an electric parking brake to which the present invention is applied will be described below. This inspection method and inspection apparatus are used, for example, in a pre-shipment inspection after assembling a new vehicle, and the inspection device is provided in a part of a new vehicle inspection line.
FIG. 1 is a schematic diagram illustrating a configuration of a vehicle including an electric parking brake to be inspected and an electric parking brake inspection device. FIG. 2 is a block diagram showing a circuit configuration of the electric parking brake and the electric parking brake inspection device.

The vehicle 1 includes a parking brake 10, an actuator unit 20, a battery 30, an electric parking brake controller 40, and a vehicle side unit 50 as an electric parking brake device.
The parking brake 10 is a braking device that prevents the vehicle from moving when the vehicle is parked or the like, for example, by braking the wheels of the vehicle. The parking brake 10 is provided on each of the wheel hub portions of the left and right rear wheels of the vehicle. The parking brake 10 includes a brake drum (not shown) disposed on the inner diameter side of a rotor of a disc brake used as a foot brake (main brake) and a brake shoe (not shown) that pressurizes and contacts the inner diameter side of the brake drum during braking. I have.

The actuator unit 20 drives the shoe of the parking brake 10 and makes a transition between a braking state in which the parking brake 10 generates a braking force and a released state in which the braking force is not substantially generated. The actuator unit 20 includes a parking brake cable 21 and is fixed to, for example, a floor panel portion of the vehicle.
For example, the actuator unit 20 reduces the rotational force of a direct current (DC) motor by a reduction gear train, rotates a lead screw, and pulls or relaxes the parking brake cable 21 by an equalizer screwed to the lead screw. is there.

The parking brake cables 21 are provided corresponding to the left and right parking brakes 10, respectively, and have flexibility so as to be deformed according to a stroke of a rear suspension (not shown). The parking brake cable 21 brings the parking brake 10 into a braking state by being pulled, and releases the parking brake 10 by being relaxed.
Here, the actuator unit 20 has a function of adjusting the braking force of the parking brake 10 in the braking state by adjusting the tension applied to the parking brake cable 21. The tension is adjusted by changing the stroke with which the actuator unit 20 pulls the parking brake cable 21. For this reason, the actuator unit 20 includes a stroke sensor (not shown) that detects this stroke.

The battery 30 is a secondary battery that is used as a main power source for a vehicle electrical system, and generates, for example, a DC 12V terminal voltage. The battery 30 includes a plus terminal 31 and a minus terminal 32.
The plus terminal 31 is connected to the electric parking brake controller 40 and the vehicle side unit 50 via wiring (harness).
The minus terminal 32 is grounded with respect to the vehicle body.

The electric parking brake controller 40 includes an ECU 41, a relay 42, and an operation switch 43, and is a control unit that controls the electric parking brake device.
The ECU 41 determines whether or not the parking brake 10 needs to be braked according to inputs from the operation switch 43 and the vehicle-side unit 50, and controls the relay 42 according to the determination result.

  The relay 42 supplies driving power to the actuator unit 20 in accordance with a control signal output from the ECU 41. The relay 42 shifts the parking brake 10 from the braking state to the released state, and changes from the released state to the braking state. In order to perform this transition, the function of reversing the polarity of the driving power is provided, and the actuator unit 20 is in a neutral state in which conduction with the actuator unit 20 is interrupted except when the actuator unit 20 is driven.

  The operation switch 43 is an operation unit through which a user inputs a manual selection operation of the braking state and the release state of the parking brake 10, and includes, for example, a push button switch mounted on an instrument panel (not shown) of the vehicle. The operation switch 43 transmits the input to the ECU 41, and the ECU 41 controls the relay 42 according to this to supply driving power to the actuator unit 20 and drive the parking brake 10.

  The vehicle side unit 50 includes, for example, an engine control unit (ECU) that controls an engine of the vehicle, a transmission control unit (TCU) that controls a transmission (transmission), a VDC control unit that performs VDC control including ABS control, It has a vehicle integration unit that controls all other electrical components.

  The vehicle-side unit 50 sequentially provides the electric parking brake controller 40 with information such as the engine speed, the accelerator opening, the transmission shift position, the foot brake operation status, and the wheel rotation speed, for example. If the electric parking brake controller 40 determines that the vehicle has shifted from the running state to the stopped state based on these inputs, the electric parking brake controller 40 shifts the parking brake 10 from the released state to the braking state. On the other hand, when the electric parking brake controller 40 determines that the vehicle shifts from the stopped state to the traveling state, the electric parking brake controller 40 shifts the parking brake 10 from the braking state to the released state.

The electric parking brake inspection device 100 includes an information processing unit 110, a communication unit 120, and a brake tester 130.
The information processing unit 110 comprehensively controls each unit of the electric parking brake inspection device 100 and processes information input from the communication unit 120 and the brake tester 130, respectively.

  The communication unit 120 is connected to the electric parking brake controller 40 on the vehicle 1 side and relays communication between the information processing unit 110 and the electric parking brake controller 40. A control signal output unit that outputs a forced drive instruction and a release instruction.

The brake tester 130 includes a roller on which a wheel (rear wheel in this embodiment) to be braked by the parking brake 10 of the vehicle 1 is mounted, and the wheel is rotated by driving the roller to rotate. This is a braking force detector that detects the braking force of the parking brake 10 based on the absorbed power.
In addition, the brake tester 130 is controlled by the information processing unit 110 to start and stop its rotational driving and detection of the braking force, and has a function of transmitting a detection output of the braking force to the information processing unit 110. .

FIG. 3 is a flowchart showing an electric parking brake inspection method using the electric parking brake inspection device of the present embodiment. Hereinafter, the steps will be described step by step.
(Step S01: Automatic inspection mode on)
The vehicle 1 is set on the brake tester 130 with the parking brake 10 released, and after the communication unit 120 is connected to the electric parking brake controller 40, the information processing unit 110 sets the automatic inspection mode on. As a result, processing described below is started.
(Step S02: Counter value N reset)
The information processing unit 110 resets an integer N, which is a counter value indicating the number of braking / release times in the electric parking brake inspection, as N = 0.

(Step S03: Forced drive instruction input (target braking force A))
The information processing unit 110 inputs a forced drive instruction to the electric parking brake controller 40 via the communication unit 120. This forcible drive instruction is a control signal including a command for driving the actuator unit 20 to shift the parking brake 10 from the released state to the braking state, and the target braking force that the parking brake 10 should generate at a minimum in the design of the vehicle. Information on A is included.
The electric parking brake controller 40 receives this forcible driving instruction and starts supplying power to the actuator unit 20 to drive the parking brake 10, thereby starting to increase the braking force.

(Step S04: Monitoring of braking force history)
The brake tester 130 sequentially detects and transmits the braking force (actual braking force) actually generated by the parking brake 10 to the information processing unit 110 while rotating the wheels. The information processing unit 110 monitors the history of the braking force that is sequentially input. Here, the rotational drive of the brake tester 130 and the detection of the braking force are automatically performed based on a control signal from the information processing unit 110.
(Step S05: Determination of maximizing braking force)
The information processing unit 110 determines whether or not the increase in the braking force has been reached and has reached the maximum value. If it is determined that the braking force has reached the maximum value, the driving of the parking brake 10 has been ended. Proceed to step S06. On the other hand, if the increase in braking force continues, the process returns to step S04 and the subsequent processing is repeated.

(Step S06: Maximum braking force F recording)
The information processing unit 110 records the current braking force (maximum braking force) as the braking force F.
(Step S07: braking time t1 recording)
The information processing unit 110 records the time from when the forced driving instruction is input to the electric parking brake controller 40 in step S03 until the braking force becomes maximum in step S05 as the braking time t1.

(Step S08: Release instruction output)
The information processing unit 110 inputs a release instruction to the electric parking brake controller 40 via the communication unit 120. This release drive instruction is a control signal including a command to drive the actuator unit 20 in the direction opposite to that in the forced drive described above to shift the parking brake 10 from the braking state to the release state.
In response to this release instruction, the electric parking brake controller 40 starts supplying electric power to the actuator unit 20 to drive the parking brake 10, whereby the braking force starts to decrease.

(Step S09: Braking force history monitor)
The information processing unit 110 monitors the braking force history in the same manner as in step S04.
(Step S10: Electric parking brake release determination)
The information processing unit 110 determines whether or not the parking brake 10 is completely released and its driving is stopped, and substantially no braking force is generated, and if it is determined that the release is completed, the brake tester The detection of the braking force by 130 is terminated, and the process proceeds to step S11. On the other hand, when it is determined that the braking force is still generated and the release is not completed, the process returns to step S09 and the subsequent processing is repeated.
(Step S11: Release time t2 recording)
The information processing unit 110 records the time from when the release instruction is input to the electric parking brake controller 40 in step S08 until the release is completed in step S10 as the release time t2.

(Step S12: Evaluation of braking force)
The information processing unit 110 compares the target braking force A with the actual braking force F recorded in step S06, and if the expression 1 is satisfied, the process proceeds to step S13, and if not, the process proceeds to step S16.
A × 1.3>F> A (Formula 1)
(Step S13: Braking time evaluation)
The information processing unit 110 compares the preset target braking time T1 with the actual braking time t1 recorded in step S07. If t1 <T1, the process proceeds to step S14, and if t1 ≧ T1 Advances to step S16.
(Step S14: Release time evaluation)
The information processing unit 110 compares the preset target release time T2 with the actual release time t2 recorded in step S11. If t2 <T2, the process proceeds to step S15, and if t2 ≧ T2 Advances to step S16.

(Step S15: Inspection OK determination)
The information processing unit 110 determines that the inspection result is normal (OK), outputs that fact to a display device or the like (not shown), and proceeds to step S19.

(Step S16: N increment)
The information processing unit 110 adds 1 to the previous counter value N to obtain N + 1, and proceeds to step S17.
(Step S17: Inspection number upper limit judgment)
The information processing unit 110 determines whether or not the counter value N has reached P, which is a preset upper limit number of braking / release. If N = P, the process proceeds to step S18, where N <P. In this case, the process returns to step S03 and the subsequent processing is repeated.
(Step S18: Inspection NG determination)
The information processing unit 110 determines that the inspection result is abnormal (NG), outputs that fact to a display device or the like (not shown), and interrupts the processing.

(Step S19: Stroke sensor zero point correction)
The information processing unit 110 outputs a stroke sensor zero point correction instruction to the electric parking brake controller 40 via the communication unit 120. Receiving this, the electric parking brake controller 40 performs zero point correction of the stroke unit of the actuator unit 20. This zero point correction is performed in order to finely adjust the traction stroke in accordance with the manufacturing tolerance of the parking brake cable 21 and the length variation caused by the elongation.

As described above, according to this embodiment, the following effects can be obtained.
(1) A forced driving instruction including information on the target braking force A is input to the electric parking brake controller 40, and the braking force F actually generated by the parking brake 10 in accordance with the forced driving instruction is converted into the target braking force A. Therefore, it is possible to quantitatively evaluate the excess or deficiency of the braking force of the electric parking brake. As a result, accurate evaluation can be performed while eliminating the influence of variations among workers.
(2) The responsiveness to the control of the electric parking brake can be evaluated by measuring the braking time t1 and the release time t2 of the parking brake 10 and comparing them with the target braking time T1 and the target release time T2.
(3) Since the information processing unit 110 automatically inputs various instructions to the electric parking brake controller 40, operates the brake tester 130, and determines each evaluation item, the man-hour required for the electric parking brake inspection is reduced. Can do.

(Modification)
The present invention is not limited to the embodiments described above, and various modifications and changes are possible, and these are also within the technical scope of the present invention.
(1) The present invention can be applied not only to inspection before shipment of a new vehicle but also to inspection after maintenance / repair, for example. In this case, for example, a portable monitor terminal used for general maintenance / inspection or the like may be used as the information processing unit and the control signal output unit of the inspection apparatus, and the brake tester may be connected to the portable monitor terminal.
(2) Items in the inspection are not limited to those in the above-described embodiments, and can be added as appropriate. For example, when the electric parking brake has a normal braking mode and an additional pulling mode in which the braking force is larger than the normal braking mode, a different target braking force is set for each mode, and the braking force or the like is set for each mode. You may make it evaluate.
(3) In the embodiment, the completion of the braking operation is detected based on the braking force reaching the maximum value, and the completion of the releasing operation is detected based on the fact that the braking force substantially disappears. Instead of this, information related to the control of the actuator may be acquired from the control unit on the electric parking brake side and detected.

It is the schematic which shows the structure of the vehicle provided with the electric parking brake test | inspection apparatus to which this invention is applied, and the electric parking brake of test object. It is a block diagram which shows the circuit structure of the electric parking brake test | inspection apparatus and electric parking brake of FIG. It is a flowchart which shows operation | movement (electric parking brake test | inspection method) of the electric parking brake test | inspection apparatus of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle 10 Parking brake 20 Actuator unit 30 Battery 40 Controller 50 Vehicle side unit 100 Electric parking brake test | inspection apparatus 110 Information processing part 120 Communication part 130 Brake tester

Claims (6)

In an inspection method of an electric parking brake provided on a vehicle wheel and driven by an actuator,
A braking instruction step for instructing the controller for controlling the electric parking brake to generate a predetermined target braking force;
A braking force detection step of detecting an actual braking force generated by the electric parking brake;
An inspection method for an electric parking brake, comprising: a braking force comparison step for comparing the target braking force with the actual braking force. In the inspection method of the electric parking brake according to claim 1,
An inspection method for an electric parking brake, comprising: a braking time evaluation step for comparing a time until the driving of the electric parking brake is completed after execution of the braking instruction step with a target braking time. In the inspection method of the electric parking brake according to claim 1 or claim 2,
A release instruction step for instructing the controller to release the electric parking brake when the electric parking brake is in a braking state;
An inspection method for an electric parking brake, comprising: a release time evaluation step for comparing a time until the electric parking brake is released after execution of the release instruction step with a target release time. In an inspection device for an electric parking brake provided on a wheel of a vehicle and driven by an actuator,
A control signal output unit that is connected to a control unit that controls the electric parking brake and outputs an instruction to generate a predetermined target braking force to the control unit;
A braking force detector for detecting a braking force generated by the electric parking brake;
An inspection device for an electric parking brake, comprising: an information processing unit that compares the target braking force with an output of the braking force detection unit. The electric parking brake inspection device according to claim 4,
The information processing unit has a function of comparing a braking time until the driving of the electric parking brake is completed after the control signal output unit outputs the target braking force generation instruction with a target braking time. An inspection device for an electric parking brake. In the inspection device of the electric parking brake according to claim 4 or claim 5,
The control signal output unit has a function of outputting a release instruction to release the electric parking brake to the control unit,
The information processing unit has a function of comparing a release time until the electric parking brake is released after the control signal output unit outputs the release instruction with a target release time. Brake inspection device.

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