JP5531912B2 - Solenoid drive - Google Patents

Description

  The present invention relates to a solenoid driving device, and more particularly to a solenoid driving device that suppresses heat generated during driving.

  Brake control is performed by controlling a hydraulic actuator of a brake system mounted on the vehicle. The hydraulic actuator includes an electromagnetically operated electromagnetic valve that controls inflow and outflow of brake fluid flowing into the wheel cylinder. The solenoid valve is provided with a solenoid, and the solenoid is driven by receiving a drive current from a power supply unit. Energization between the solenoid and the power supply unit is controlled by turning the relay on and off.

  In the brake control device of the brake-by-wire system, when the braking force is controlled, the opening / closing control of the electromagnetic valve is always performed. As a result, there is a tendency that the amount of heat generated in the power supply unit and relay that controls the solenoid of the solenoid valve increases. In addition, when one solenoid is driven by a plurality of power supply units and relays, the amount of heat generated by the power supply unit and the entire relay increases.

  This invention is made | formed in view of such a condition, The objective is to provide the solenoid drive device which can suppress the heat | fever which generate | occur | produces at the time of a drive.

In order to solve the above problems, a solenoid drive device according to an embodiment of the present invention includes a first relay for turning on or off the energization to drive the solenoid, since the first relay to drive the solenoid from another system A second relay that turns on or off the power supply, and a control unit that controls on and off of the first relay and the second relay. The control unit alternately switches the energization of the solenoid from the first relay and the second relay while maintaining the energization of the solenoid at normal time, and switches the energization of the first relay and the second relay while switching the energization of the solenoid. Each energization is controlled to be on for a predetermined time, and the control unit monitors the energization state from the first relay to the solenoid and the energization state from the second relay to the solenoid. A second energization monitoring unit. When the first energization monitoring unit or the second energization monitoring unit detects that one of the first relay and the second relay is defective, the control unit performs control so that the solenoid is energized by the other relay. According to this aspect, heat generated during driving can be suppressed.

  According to the solenoid driving device of the present invention, heat generated during driving can be suppressed.

1 is a conceptual diagram illustrating a configuration of a solenoid driving device and a solenoid according to an embodiment. It is a figure explaining the energized state of the solenoid and relay in a comparison technique. (A) And (b) is a figure explaining the electricity supply method to the solenoid in the solenoid drive device which concerns on embodiment.

  FIG. 1 is a conceptual diagram illustrating a configuration of a solenoid driving device 100 and a solenoid 40 according to the embodiment. The solenoid drive device 100 drives the solenoid 40, and includes a first power supply unit 30 and a second power supply unit 32 (referred to as “power supply unit” if they are not distinguished from each other), and an ECU 50. The ECU 50 includes a first relay 20 and a second relay 22 that supply drive current to the solenoid 40 (referred to as “relay” if they are not distinguished from each other), and an integrated IC 10 that controls the first relay 20 and the second relay 22. .

  The integrated IC 10 sends a control signal for driving the solenoid 40 to the first relay 20 and the second relay 22. When receiving the control signal from the integrated IC 10, the first relay 20 and the second relay 22 turn on or off the energization between the power supply unit and the solenoid 40 in accordance with the control signal.

  The integrated IC 10 includes a first energization monitoring unit 12 and a second energization monitoring unit 14, and the first energization monitoring unit 12 and the second energization monitoring unit 14 detect the current values of the first relay 20 and the second relay 22. ,Monitor. A current value may be detected by using a shunt resistor for the first relay 20 and the second relay 22.

  In the embodiment, the solenoid 40 is supplied with a drive current from the power supply unit via the first relay 20 and the second relay 22. The solenoid 40 is grounded to the ground 34. The solenoid is provided, for example, in an electromagnetic valve disposed in a hydraulic actuator unit of an electronically controlled brake system (ECB) for a vehicle. The hydraulic actuator unit appropriately adjusts the hydraulic pressure of the brake fluid supplied from the power hydraulic pressure source or the master cylinder unit with an electromagnetic valve, and sends it to the disc brake unit. Thereby, the braking force with respect to each wheel by hydraulic braking is adjusted. The hydraulic actuator unit is provided with a plurality of solenoid valves, and a solenoid is provided for each of the plurality of solenoid valves.

  When a predetermined drive current is supplied from the first relay 20 and the second relay 22 provided in the vehicle, the solenoid valve opens or closes, and distributes or blocks the brake fluid. For example, in a normally open type solenoid valve, when a predetermined drive current is supplied to the solenoid coil, the valve element coupled to the solenoid moves toward the valve seat together with the solenoid, and the valve element contacts the valve seat. The hole provided in the valve seat is closed and the flow of brake fluid is blocked. The ECU 50 generates heat as the solenoid 40 is driven.

  The solenoid receives a drive current from the first relay 20 and the second relay 22. This is provided from the viewpoint of fail-safe so that the drive current can be supplied from the other relay even if the drive current cannot be supplied from one relay to the renoid. For this reason, the amount of heat generated in the entire relay is increased as compared with the case of controlling with one relay. Therefore, the solenoid driving device 100 performs control for suppressing the heat generation of the ECU 50.

  FIG. 2 is a diagram for explaining energization states of solenoids and relays in the comparative technique. In FIG. 2, the horizontal axis indicates time, and the vertical axis indicates energization on and off. The energization state of the solenoid 40 is 100%. The 100% energization state refers to a state where a sufficient energization amount is ensured with respect to the energization amount commanded by the integrated IC 10, and refers to a state where a desired energization amount of the integrated IC 10 is supplied.

  In the comparative technique, when the solenoid 40 is in a 100% energized state, the drive current is supplied from both the first relay 20 and the second relay 22 in an equivalent 100% energized state.

  When driving the solenoid 40, if for some reason it becomes impossible to supply the driving current from the first relay 20, the driving current is supplied as it is from the second relay 22 without stopping the solenoid 40. Can be driven. According to this aspect, when the solenoid is driven, the heat generation amount is doubled as compared with the case where one solenoid is driven by one current supply path. Therefore, in the solenoid drive device 100 of the embodiment, the integrated IC 10 performs control so as to suppress the energization amounts of the two current supply paths.

  FIG. 3 is a diagram illustrating a method for energizing the solenoid 40 in the solenoid driving apparatus 100 according to the embodiment. FIG. 3A shows an energization method in a normal case, and FIG. 3B shows an energization method in the case where the second relay 22 cannot be energized. In FIG. 3, the horizontal axis represents time, and the vertical axis represents energization on and off. On / off of energization of the first relay 20 and the second relay 22 is controlled by the integrated IC 10.

  In the normal time shown in FIG. 3A, the solenoid 40 starts to be driven from time T1, and the desired energization state of the integrated IC 10 is maintained. At time T1, the energization of the first relay 20 is switched from OFF to ON, and supply of drive current from the first relay 20 to the solenoid 40 is started. On the other hand, the energization of the second relay 22 remains off at time T1. At time T2, in addition to the first relay 20, the energization of the second relay 22 is also turned on, and the drive current is supplied from the first relay 20 and the second relay 22 to the solenoid 40.

  At time T3, the energization of the first relay 20 is turned off, and the drive current is supplied from the second relay 22 to the solenoid 40. At time T4, the energization of the first relay 20 is turned on again, and the drive current is supplied from the first relay 20 and the second relay 22 to the solenoid 40.

  At time T5, the energization of the second relay 22 is turned off, and the drive current is supplied to the solenoid 40 only from the first relay 20. Thus, while the energization of the solenoid 40 is turned on, the energization amount of the first relay 20 and the second relay 22 is reduced by repeatedly turning on / off the energization of the first relay 20 and the second relay 22. And the amount of heat generated in the integrated IC 10 can be suppressed. In addition, relay switching is performed between time 2 and time T3, and at a predetermined time between time T4 and time T5. In relay switching, both the first relay 20 and the second relay 22 are turned on for a predetermined time. It is in a state. Thus, it is possible to avoid a rise when energization is turned on or a response delay of the relay, and to reliably maintain a desired energization state of the solenoid 40 without temporarily stopping the solenoid 40.

  The integrated IC 10 monitors the energization state from the first relay 20 and the second relay 22 to the solenoid 40 by the first energization monitoring unit 12 and the second energization monitoring unit 14. The integrated IC 10 compares the control information instructed to the first relay 20 and the energization state of the first relay 20 acquired by the first energization monitoring unit 12 to determine whether there is a problem in the energization state of the first relay 20. To detect. For example, even if a control signal indicating energization on is sent to the first relay 20, the integrated IC 10 detects that there is a problem such as disconnection if the current detected by the first energization monitoring unit 12 remains zero. Similarly, the integrated IC 10 compares the control information instructed to the second relay 22 with the energization state of the second relay 22 acquired by the second energization monitoring unit 14 and disconnects the energization state of the second relay 22. Detect whether there are any problems. Thereby, the malfunction of the energization state of the 1st relay 20 and the 2nd relay 22 can be detected, and it can be monitored whether it can energize to the solenoid 40 from each electric current supply path | route. When the integrated IC 10 detects a failure in the energization state of the first relay 20 or the second relay 22, the integrated IC 10 changes the energization method to the solenoid 40.

  As shown in FIG. 3B, the energized state of the solenoid 40 is 100% from the time S. When the second relay 22 becomes unable to be energized due to a malfunction, only the first relay 20 supplies the drive current to the solenoid 40. Thereby, the energized state of the solenoid 40 can be maintained at 100%.

  Specifically, when the integrated IC 10 detects that the second energization monitoring unit 14 detects a problem in the energization state of the second relay 22, the integrated IC 10 stops switching the relay and thereafter energizes the solenoid 40. 20 only. In other words, the integrated IC 10 monitors the energization state of the first relay 20 and the second relay 22 by the first energization monitoring unit 12 and the second energization monitoring unit 14 and detects a failure of either one of the relays, only the other relay. As a result, the solenoid 40 is energized. Thereby, it is possible to maintain energization to the solenoid 40 even if a problem occurs in one current supply path.

  Although the embodiment has been described in which the solenoid is provided in the electromagnetic valve disposed in the ECB, the solenoid driving device 100 can naturally be used for other solenoids.

  The present invention is not limited to the above-described embodiments, and various modifications such as design changes can be added based on the knowledge of those skilled in the art. The configuration shown in each figure is for explaining an example, and any configuration that can achieve the same function can be changed as appropriate, and the same effect can be obtained.

  DESCRIPTION OF SYMBOLS 10 Integrated IC, 12 1st electricity supply monitoring part, 14 2nd electricity supply monitoring part, 20 1st relay, 22 2nd relay, 30 1st power supply part, 32 2nd power supply part, 34 Ground, 40 Solenoid, 50 ECU, 100 Solenoid drive.

Claims (1)

A first relay that turns on or off energization for driving the solenoid;
A second relay that turns on or off energization for driving the solenoid from a system different from the first relay;
A controller that controls on and off of the first relay and the second relay,
The control unit alternately switches the energization of the solenoid from the first relay and the second relay while maintaining the energization of the solenoid at a normal time, and switches the energization of the solenoid while switching the energization to the solenoid. Controlling the energization of each of the first relay and the second relay to be on for a predetermined time;
The control unit includes a first energization monitoring unit that monitors an energization state from the first relay to the solenoid, and a second energization monitoring unit that monitors an energization state from the second relay to the solenoid. ,
When the control unit detects that one of the first relay and the second relay is defective by the first energization monitoring unit or the second energization monitoring unit, the other relay energizes the solenoid. The solenoid drive device characterized by controlling so that.

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