Vehicle brake hydraulic pressure controller

Patent metadata

Field	Value
Publication number	US-9120470-B2
Application number	US-201313852090-A
Country	US
Kind code	B2
Filing date	Mar 28, 2013
Priority date	Mar 28, 2012
Publication date	Sep 1, 2015
Grant date	Sep 1, 2015

Abstract

An embodiment provides a vehicle brake hydraulic pressure controller capable of carrying out a brake hydraulic pressure control in a plurality of control modes depending on a situation of a vehicle. The vehicle brake hydraulic pressure controller includes: proportional solenoid valves provided in passages connecting a master cylinder and wheel brakes of the vehicle, and configured to be controlled at preset drive frequencies; a control mode selecting section configured to select, in the case that two or more control modes are requested simultaneously, one of the two or more requested control modes; and a frequency selecting section configured to select one of the drive frequencies correspondingly with the one of the two or more requested control modes selected by the control mode selecting section.

First claim

The invention claimed is:

1. A vehicle brake hydraulic pressure controller capable of carrying out a brake hydraulic pressure control in a plurality of control modes depending on a situation of a vehicle, comprising:
proportional solenoid valves provided in passages connecting a master cylinder and wheel brakes of the vehicle, and configured to be controlled at preset drive frequencies, the drive frequencies being set correspondingly with the control modes such that the drive frequency for the control mode in a vehicle stopping state is higher than the drive frequency for the control mode in a vehicle traveling state;
a control mode selecting section configured to select, in the case that two or more control modes are requested simultaneously, one of the two or more requested control modes based on a magnitude of a control pressure of each requested control mode; and
a frequency selecting section configured to select one of the drive frequencies correspondingly with the one of the two or more requested control modes selected by the control mode selecting section,
wherein the control mode in the vehicle traveling state includes:
a skid suppression control mode (AYC mode) in which a skidding of the vehicle is detected to be suppressed,
a traction control mode (TCS mode) in which a racing of at least one wheel is detected to be suppressed, and
a brake assist control mode (BA mode) in which a braking is assisted by increasing a brake hydraulic pressure upon detection of a sudden braking,
wherein, in the case that the AYC mode and the TCS mode are requested simultaneously, the control mode selecting section selects either mode having higher control pressure, and
wherein, in the case that the AYC mode, the TCS mode and the BA mode are requested simultaneously, the control mode selecting section:
compares a first control pressure obtained by adding the control pressures in the AYC mode and the BA mode with a second control pressure obtained by adding the control pressures in the TCS mode and the BA mode,
selects, in the case that the first control pressure is higher than the second control pressure, a first control mode in which the BA mode is carried out at the first control pressure, and
selects, in the case that the first control pressure is equal to or less than the second control pressure, a second control mode in which the BA mode is carried out at the second control pressure.

2. The vehicle brake hydraulic pressure controller of claim 1 ,
wherein the control mode in the vehicle stopping state includes a first vehicle-stop holding mode requested on an uphill road and a second vehicle-stop holding mode requested during an engine idling stop, and
wherein the drive frequency in the second vehicle-stop holding mode is set higher than that in the first vehicle-stop holding mode.

3. The vehicle brake hydraulic pressure controller of claim 2 ,
wherein, in the case that the first vehicle-stop holding mode and the second vehicle-stop holding mode are requested simultaneously, the control mode selecting section selects either mode having higher control pressure.

4. The vehicle brake hydraulic pressure controller of claim 1 ,
wherein the control section includes the control mode selecting section, a hydraulic pressure controlling section, a valve drive section, a motor drive section and a storage section.

5. The vehicle brake hydraulic pressure controller of claim 4 ,
wherein the control mode selecting section judges which one of plural control modes is requested, wherein the plural control modes comprises:
a hill-start assist mode (HSA mode) requested on an uphill road as a first vehicle-stop holding mode,
a creep aid system mode (CAS mode) requested during an engine idling stop as a second vehicle-stop holding mode,
the AYC mode in which skidding of the vehicle is detected to be suppressed,
the TCS mode in which racing of at least one wheel is detected to be suppressed, and
the BA mode in which sudden braking is detected and the braking is assisted by increasing brake hydraulic pressure.

6. The vehicle brake hydraulic pressure controller of claim 5 ,
wherein the two or more control modes having higher control pressure is always selected such that both control requests of the two or more control modes are satisfied.

7. The vehicle brake hydraulic pressure controller of claim 5 ,
wherein in case that it is judged that the AYC mode, the TCS mode and the BA mode are requested simultaneously, the control mode selecting section calculates the first control pressure by adding respective control pressures in the AYC mode and the BA mode, and calculates the second control pressure by adding respective control pressures in the TCS mode and the BA mode and the control mode selecting section compares the calculated first control pressure with the calculated second control pressure.

8. The vehicle brake hydraulic pressure controller of claim 5 ,
wherein the valve drive section includes a control valve unit drive section which controls an inlet valve and outlet valve on a basis of pressure raising, holding or reducing instructions of the hydraulic pressure controlling section.

9. The vehicle brake hydraulic pressure controller of claim 8 ,
wherein in case that a pressure in a wheel cylinder is raised, no current is applied to the inlet valve and the outlet valve,
wherein in case that the pressure in the wheel cylinder is reduced, signals are transmitted to both the inlet valve and the outlet valve to close the inlet valve and to open the outlet valve, thereby discharging brake fluid of the wheel cylinder through the outlet valve, and
wherein in case that the pressure in the wheel cylinder is held, a signal is transmitted to the inlet valve and no current is applied to the outlet valve, thereby closing both the inlet valve and the outlet valve.

10. The vehicle brake hydraulic pressure controller of claim 5 ,
wherein the control section first judges whether at least one of the BA mode, the AYC mode and the TCS mode is requested,
wherein in case that it is judged that at least one of the BA mode, the AYC mode and the TCS mode in the vehicle traveling state is requested, the control section judges whether the BA mode is requested, and
wherein in case that it is judged that the BA mode is requested, the control section further judges whether at least one of the AYC mode and the TCS mode is requested.

11. The vehicle brake hydraulic pressure controller of claim 10 ,
wherein in case that it is judged that at least one of the AYC mode and the TCS mode is requested, the control section selects the AYC+BA mode or the TCS+BA mode, whichever has higher control pressure and selects a drive frequency corresponding to the selected control mode from a table.

12. The vehicle brake hydraulic pressure controller of claim 10 ,
wherein in case that one of the AYC mode and the TCS mode is requested in addition to the BA mode, the control pressure in the control mode not requested becomes zero.

13. The vehicle brake hydraulic pressure controller of claim 10 ,
wherein in case that it is judged that neither the AYC mode nor the TCS mode is requested, the control section selects the BA mode and selects a drive frequency corresponding to the selected BA mode from a table.

14. The vehicle brake hydraulic pressure controller of claim 10 ,
wherein in case that it is judged that the BA mode is not requested, the control section selects the AYC mode or the TCS mode, whichever has higher control pressure and selects a drive frequency corresponding to the selected control mode from a table.

15. The vehicle brake hydrau

Assignees

• Nissin Kogyo Kk

Inventors

• Harada Yutaka

Classifications

• B60T7/12 Primary

  for automatic initiation; for initiation not subject to will of driver or passenger {(limiting speed of vehicles other than rail vehicles B60K31/00)} · CPC title

• B60T8/175

  Brake regulation specially adapted to prevent excessive wheel spin during vehicle acceleration, e.g. for traction control (safety devices for propulsion unit control responsive to, or preventing, skidding of wheels B60K28/16) · CPC title

• B60T2201/06

  Hill holder; Start aid systems on inclined road · CPC title

• B60T8/1761 Primary

  responsive to wheel or brake dynamics, e.g. wheel slip, wheel acceleration or rate of change of brake fluid pressure · CPC title

• B60T2201/03

  Brake assistants · CPC title