JP2018121424A - Brake control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a brake control device that can determine a failure without increasing input devices to be used and can maintain control according to the purpose of vehicle operation even if a failure occurs.SOLUTION: The brake control device comprises: brake operation amount detecting means that detects operation amounts of a brake pedal 11; regenerative control means 72 that sets on a rotary electric machine 9 regenerative torque corresponding to the operation amounts detected by the brake operation amount detecting means; brake operation detecting means that detects that the brake pedal is operated by operation amounts more than prescribed operation amounts; accelerator operation detecting means that detects whether the accelerator pedal 31 is turned on or off; and abnormality determining means 71 that determines an abnormality state from information from the brake operation amount detecting means and information from the brake operation detecting means. The regenerative control means changes regenerative control when the abnormality determining means determines an abnormality.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a brake control device that controls a regenerative braking force, and more particularly to a brake control device that can detect a failure of an input device that determines a regenerative braking force and can perform optimal control even when the failure occurs.

  The brake control device that controls the regenerative braking force causes the rotating electrical machine to generate a regenerative braking force corresponding to the amount of operation of the brake pedal. The operation amount of the brake pedal is detected by an operation amount detection means (stroke sensor), and a regenerative braking force corresponding to the operation amount of the brake pedal is generated by the rotating electrical machine.

  By the way, two operation amount detection means (stroke sensor) for detecting the operation amount of the brake pedal and an operation detection means (stop lamp switch) for detecting the operation of the brake pedal are provided. A technique has been proposed in which when either one fails, the amount of operation of the brake pedal is detected and the regenerative braking force of the rotating electrical machine is controlled based on the other and the operation detection means. According to this technique, even when one of the two operation amount detection means fails, the regenerative braking force corresponding to the operation amount of the brake pedal is generated by the rotating electrical machine. Thereby, even if any one of the two operation amount detection means breaks down, the uncomfortable feeling given to the driver can be reduced (see, for example, Patent Document 1).

  However, since the technique described in Patent Document 1 described above includes two operation amount detection means, the cost is increased and the control procedure is more complicated than when only one operation amount detection means is provided.

  In view of this, a brake control device that controls the regenerative control force using a limit switch instead of a single operation amount detection means (stroke sensor) has been proposed (see, for example, Patent Document 2). ).

JP 2010-149797 A Japanese Patent Laying-Open No. 2015-29292

  However, this technique has a problem that it cannot cope with a failure of the limit switch or a failure of both the stroke sensor and the limit switch.

  In addition, in order to determine the failure of the stroke sensor or limit switch, it is necessary to use an input device other than these, and there is a problem that the structure of hardware and software becomes complicated.

  Furthermore, if these are left unattended, there will be a failure to output data indicating that the stroke sensor is operating, and if the limit switch is also on-fixed, there may be regenerative control that does not meet the purpose of vehicle operation. There is a problem.

  The present invention has been made in view of such circumstances, and it is possible to determine a failure without increasing the number of input devices to be used, and to perform control in accordance with the purpose of vehicle operation even when a failure has occurred. An object of the present invention is to provide a brake control device that can be maintained.

  An aspect of the present invention that solves the above problems includes a brake operation amount detection unit that detects an operation amount of a brake pedal, and a regenerative control that sets a regenerative torque corresponding to the operation amount detected by the brake operation amount detection unit in a rotating electrical machine. Means, a brake operation detecting means for detecting that the brake pedal is operated more than a predetermined predetermined operation amount, an accelerator operation detecting means for detecting on / off of the accelerator pedal, and information from the brake operation amount detecting means, An abnormality determination unit that determines an abnormal state from information from the brake operation detection unit, and the regeneration control unit changes the regeneration control when the abnormality determination unit determines abnormality. It is in the brake control device.

  In such an aspect, the brake operation amount detection unit includes an abnormality determination unit that determines an abnormal state from the information from the brake operation amount detection unit and the information from the brake operation detection unit without adding a special input device. Thus, an abnormal state such as a failure of the brake operation detecting means can be determined, and based on this, it can be changed to an appropriate regenerative control, and the control in accordance with the purpose of the vehicle operation can be maintained.

  Here, the abnormality determination means is configured such that the brake operation detection means is on, but the operation amount from the brake operation amount detection means is not equal to or greater than the predetermined operation amount, or the brake operation detection means is off. However, it is preferable that the abnormality is determined when the operation amount from the brake operation amount detection means is equal to or larger than the offset amount that is determined not to be operated by the brake pedal.

  According to this, it is possible to determine an abnormal state such as a failure of the brake operation amount detection means and the brake operation detection means without using a special input device or performing complicated control, and based on this, an appropriate regeneration can be performed. It can be changed to control, and control in accordance with the purpose of vehicle operation can be maintained.

  Further, it is preferable that the change of the regenerative control when the abnormality determining means determines abnormality is that the regenerative control is prohibited on condition that the accelerator operation detecting means detects that the accelerator pedal is turned on.

  According to this, although there is an abnormal state such as a failure of the brake operation amount detection means or the brake operation detection means, the accelerator pedal is in an on state, so that the regenerative control is prohibited according to the purpose of the vehicle operation. It becomes.

  Further, the change of the regenerative control when the abnormality determining means determines the abnormality is maintenance of the regenerative control under the changed condition on the condition that the accelerator operation detecting means detects that the accelerator pedal is turned off. It is preferable.

  According to this, although there is an abnormal state such as a failure of the brake operation amount detection means or the brake operation detection means, the accelerator pedal is in an off state, so that at least minimum regeneration control is performed in accordance with the purpose of vehicle operation. Control.

  The maintenance of the regeneration control under the changed condition is preferably the maintenance of the minimum predetermined regeneration control or the maintenance of the regeneration control based on information from the brake operation amount detection means.

  According to this, although there is an abnormal state such as a failure of the brake operation amount detection means or the brake operation detection means, the accelerator pedal is in an off state, so that the minimum predetermined regenerative control is maintained or the brake operation amount detection means By maintaining the regenerative control based on the information from the vehicle, the control is performed in accordance with the purpose of the vehicle operation.

  According to the present invention, the brake operation amount is provided without adding a special input device by providing the abnormality determination unit that determines the abnormal state from the information from the brake operation amount detection unit and the information from the brake operation detection unit. An abnormal state such as a failure of the detecting means or the brake operation detecting means can be determined, and based on this, it can be changed to an appropriate regenerative control, and the control according to the purpose of the vehicle operation can be maintained.

It is a schematic diagram which shows the structure around the brake pedal of the motor vehicle based on this invention. It is a block diagram which shows the control structure of the brake control apparatus which concerns on embodiment of this invention. It is a flowchart which shows an example of the control flow of the brake control apparatus which concerns on embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic diagram showing a configuration around a brake pedal of an automobile. FIG. 2 is a block diagram showing a control configuration of the brake control device according to the embodiment of the present invention.

  A brake control device according to an embodiment of the present invention controls a braking force (regenerative braking force) when regenerating kinetic energy of an automobile into electric energy, and is provided at a driver seat of the automobile. The input is the amount of depression (operation amount).

  As shown in FIG. 1, the brake pedal 11 is provided at the foot of the driver's seat. The brake pedal 11 is attached so as to be rotatable with respect to the vehicle body. More specifically, the brake pedal 11 is rotatably attached to a master cylinder bracket 12 attached to the vehicle body. A master cylinder (hydraulic braking control means) 21 is attached to the vehicle front side (engine room) of the master cylinder bracket 12. The master cylinder 21 is for transmitting the depression force (operation force) of the brake pedal 11 to a hydraulic brake (mechanical brake) (not shown), and a piston (not shown) that reciprocates inside the master cylinder 21; It has a push rod 211 provided integrally with the piston. The distal end of the push rod 211 is connected to the rotation fulcrum side (base end side) of the brake pedal 11, and when the brake pedal 11 is depressed, the piston in the master cylinder 21 is pushed in via the push rod 211, and the master cylinder 21. Apply pressure to the brake fluid (brake fluid) inside. The applied pressure (hydraulic pressure) is transmitted to the hydraulic brake 22 (see FIG. 2), and a braking force is generated in the hydraulic brake 22.

  The brake pedal 11 can be adjusted with the height of the pedal before being depressed, the play from when the pedal starts to be depressed until pressure is applied to the brake fluid, and the gap between the floor board and the pedal when the pedal is most depressed. , Adjusted as appropriate. Therefore, when the brake pedal 11 is depressed, the brake pedal 11 is idled by the amount of play, and then pressure is applied to the brake fluid. Thereby, the applied pressure is transmitted to the hydraulic brake, and a braking force is generated in the hydraulic brake. Since the braking force of the hydraulic brake is proportional to the applied pressure, it is proportional to the depression force (depression amount) of the brake pedal 11.

  A return spring 13 is installed between the brake pedal 11 and the master cylinder bracket 12. Thus, when the depression of the brake pedal 11 is interrupted, the pedal height before the brake pedal 11 is depressed is restored.

  A pedal stroke sensor 3 is provided on the vehicle front side of the brake pedal 11. The pedal stroke sensor 3 is for detecting the depression amount (operation amount) of the brake pedal 11, and can detect the depression amount from the height before the brake pedal 11 is depressed to the height at which the brake pedal 11 is depressed most. is there. The pedal stroke sensor 3 converts the depression amount of the brake pedal 11 into an electric signal and outputs it. Note that an independent detection mechanism different from the master cylinder 21 is used so that the performance of the hydraulic brake is not affected even if the pedal stroke sensor 3 breaks down.

  A limit switch 4 is provided on the vehicle rear side of the brake pedal 11. The limit switch 4 is attached to the master cylinder bracket 12 via the switch bracket 14. The limit switch 4 is configured to be interlocked with the on / off of the stop lamp.

  The limit switch 4 is for lighting a stop lamp 5 (see FIG. 2) of an automobile provided at the rear of the vehicle. When the brake pedal 11 is depressed (operated exceeding a predetermined predetermined operation amount). In the case) and when the depression of the brake pedal 11 is interrupted (when the operation is interrupted).

  On the other hand, an accelerator position sensor (APS) 32 is provided on the back side of the accelerator pedal 31 to detect the amount of depression when the accelerator pedal 31 is turned on / off and turned on. In the brake control device of this embodiment, as described later, the on / off information of the accelerator position sensor 32 is used to perform abnormality determination and regenerative force control in the case of an abnormality.

  As shown in FIG. 2 which is a block diagram showing a control configuration of the brake control device, the above-described limit switch 4 is connected to the electrical system ECU 6. In the embodiment of the present invention, the electrical system ECU 6 turns on the stop lamp 5 of the automobile and outputs an on signal and an off signal of the limit switch 4 to the general ECU 7. Thereby, the electrical system ECU 6 turns on the stop lamp 5 when the limit switch 4 is turned on, and turns off the stop lamp 5 when the limit switch 4 is turned off.

  The pedal stroke sensor 3, the electrical system ECU 6 and the accelerator position sensor 32 described above are connected to the general ECU 7. In the embodiment of the present invention, the total ECU 7 controls a generator (rotating electrical machine) 9 via a generator control unit (rotating electrical machine control unit) 8 based on inputs from the pedal stroke sensor 3 and the electrical system ECU 6. It is.

  As shown in FIG. 2, the integrated ECU 7 includes an abnormality determination unit 71 and a regeneration control unit 72. The abnormality determination means 71 performs abnormality determination of the pedal stroke sensor 3 as an operation amount detection means and the limit switch 4 as a brake operation detection means very simply by the following procedure, and details will be described later. The regenerative control means 72 sets regenerative torque corresponding to the operation amount in the generator 9 based on the operation amount of the brake pedal 11. Specifically, when it is determined that the pedal stroke sensor 3 is normal, a regenerative torque corresponding to the depression amount is supplied to the generator (rotating electric machine) 9 based on the depression amount of the brake pedal 11 input from the pedal stroke sensor 3. Set. On the other hand, when the abnormality determination unit 71 determines that one of the pedal stroke sensor 3 and the limit switch 4 is abnormal, the regeneration control unit 72 is appropriately controlled based on the on / off information from the accelerator position sensor 32. The details are described later. Thereby, the drive wheel 10 is braked.

  Next, an example of a control flow of the above-described brake control device of the present embodiment will be described with reference to FIG. FIG. 3 is a flowchart illustrating an example of a control flow of the brake control device according to the embodiment.

  As shown in FIG. 3, the abnormality determination unit 71 first acquires information from a limit switch that is a brake operation detection unit, and determines whether the brake pedal 11 is in an on state or an off state (step S1). When the limit switch 4 is in the OFF state (step S1; No), information is acquired from the pedal stroke sensor 3 that is a brake operation amount detection means, and it is determined whether or not the operation amount X of the brake pedal 11 is greater than or equal to α. (Step S2). Here, α is a value for which it is determined that the brake pedal 11 is not depressed when a predetermined offset amount is set and the operation amount is smaller than α. Therefore, when the limit switch 4 is off and the operation amount X is less than α (step S2; No), the abnormal state is not fixed, and therefore, control according to the output value of the pedal stroke sensor 3 is performed and regenerative control is performed. The means 72 sets the regenerative torque corresponding to the operation amount in the generator 9 based on the operation amount of the brake pedal 11 (step S3).

  On the other hand, when the limit switch 4 is off and the operation amount X is greater than or equal to α (step S2; Yes), the abnormality determination unit 71 determines an abnormal state (step S4).

  If the abnormality determination means 71 determines an abnormal state, it acquires information from the accelerator position sensor 32 and determines whether or not the state of the accelerator pedal 31 is on (step S5). And when the accelerator pedal 31 is OFF (step S5; No), since it is suitable for the driving | running purpose to implement regenerative control, regenerative control is implemented with a predetermined regenerative amount (step S6). On the other hand, when the accelerator pedal 31 is on (step S5; Yes), prohibiting the regenerative control is suitable for the driving purpose, so the value of the operation amount X of the brake pedal 11 is returned to 0 and the regenerative control is performed. Is prohibited (step S7).

  Here, the regeneration control with the predetermined regeneration amount in step S6 may be a predetermined value set in advance, for example, the regeneration control with the minimum regeneration amount, or the output value of the pedal stroke sensor 3 It is good also as the control according to. However, when the control according to the output value of the pedal stroke sensor 3 is performed, there is a possibility that the pedal stroke sensor 3 breaks down and outputs an abnormal value, so a threshold is set and the output exceeds the threshold. It is more preferable to change the control to a predetermined value.

  When the limit switch 4 is ON in step S1 (step S1; Yes), information is acquired from the pedal stroke sensor 3 as the brake operation amount detection means, and whether or not the operation amount X of the brake pedal 11 is equal to or larger than β. Is determined (step S8). Here, β is an operation amount of the brake pedal 11 when the limit switch 4 is surely turned on, and is predetermined. When the operation amount X is β or more, it is determined that the limit switch 4 is turned on if the limit switch 4 is normal. Therefore, when the limit switch 4 is on and the manipulated variable X is less than β (step S8; No), the abnormality determining means 71 determines that it is in an abnormal state (step S4). Thereafter, the processes in steps S5 to S7 are the same as those described above.

  On the other hand, when the limit switch 4 is ON and the operation amount X is equal to or larger than β (step S8; Yes), the abnormality determination unit 71 cannot determine the abnormal state. Information is acquired from 32 and it is judged whether the state of the accelerator pedal 31 is ON (step S9). If the accelerator pedal 31 is on (step S9; Yes), prohibiting regenerative control is suitable for the purpose of operation, so the routine proceeds to step S7, where the value of the operation amount X of the brake pedal 11 is set. Return to 0 and prohibit regenerative control. On the other hand, when the accelerator pedal 31 is off (step S9; No), since the abnormal state is not fixed, control according to the output value of the pedal stroke sensor 3 is performed, and the regeneration control means 72 Based on the operation amount, the regenerative torque corresponding to the operation amount is set in the generator 9 (step S10).

  The present invention can detect an abnormal state of the operation amount detection means for detecting the operation amount of the brake pedal and the pedal operation detection means with a simple configuration without providing a special input device, and according to the driving purpose even in the abnormal state. Since the regenerative braking force can be controlled, it is suitable for a brake control device that controls the regenerative braking force of a hybrid vehicle or an electric vehicle.

3 Pedal stroke sensor 4 Limit switch 5 Stop lamp 6 Electrical system ECU
7 General ECU
11 Brake pedal 31 Accelerator pedal 32 Accelerator position sensor 71 Abnormality determination means 72 Regenerative control means

Claims (5)

Brake operation amount detection means for detecting the operation amount of the brake pedal;
Regenerative control means for setting a regenerative torque corresponding to the operation amount detected by the brake operation amount detection means to the rotating electrical machine;
Brake operation detecting means for detecting that the brake pedal has been operated by a predetermined amount or more;
An accelerator operation detecting means for detecting on / off of the accelerator pedal;
An abnormality determination means for determining an abnormal state from information from the brake operation amount detection means and information from the brake operation detection means;
With
The regenerative control means changes the regenerative control when the abnormality determination means determines an abnormality.   In the abnormality determination unit, the brake operation detection unit is on, but the operation amount from the brake operation amount detection unit is not equal to or greater than the predetermined operation amount, or the brake operation detection unit is off, 2. The brake control device according to claim 1, wherein an abnormality is determined when an operation amount from the brake operation amount detection means is equal to or greater than an offset amount at which it is determined that the brake pedal is not operated.   The regenerative control change when the abnormality determining means determines abnormality is that the regenerative control is prohibited on condition that the accelerator operation detecting means detects that the accelerator pedal is turned on. The brake control device according to 1 or 2.   The regenerative control change when the abnormality determining means determines abnormality is to maintain the regenerative control under the changed condition, provided that the accelerator operation detecting means detects that the accelerator pedal is turned off. The brake control device according to claim 1 or 2.   The maintenance of the regenerative control under the changed condition is a maintenance of a minimum predetermined regenerative control or a regenerative control based on information from the brake operation amount detection means. Brake control device.

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