Vehicle control device

Patent metadata

Field	Value
Publication number	US-10173658-B2
Application number	US-201415115496-A
Country	US
Kind code	B2
Filing date	Dec 25, 2014
Priority date	Jan 31, 2014
Publication date	Jan 8, 2019
Grant date	Jan 8, 2019

Abstract

In a vehicular brake device, while a brake operating member is not operated and a wheel cylinder pressure supplying control is executed to supply the target wheel cylinder pressure to the respective wheel cylinders individually, the vehicle control device sets the target servo pressure to a first predetermined target servo pressure which is a value smaller than a maximum output pressure of the servo pressure generating device. When the execution of the wheel cylinder pressure supplying control starts, the vehicle control device sets the target servo pressure to be the target wheel cylinder maximum value when a firstly occurred rising inclination of the target wheel cylinder maximum value is equal to or more than a minimum increment of an output of the servo pressure generating device per unit time and at the same time when the target wheel cylinder pressure is smaller than the first determined target servo pressure.

First claim

The invention claimed is:

1. A vehicle control device applicable to a vehicle brake device which includes:
a master cylinder wherein a master piston is driven to move by a servo pressure in a servo chamber and by the movement of the master piston, a master pressure in a master chamber is changed;
a servo pressure generating device which generates the servo pressure in the servo chamber, the servo pressure generating device being formed by a high pressure source, a low pressure source, a pressure increasing control valve disposed between the high pressure source and the servo chamber for controlling a flow of a brake fluid from the high pressure source to the servo chamber, and a first pressure decreasing control valve disposed between the low pressure source and the servo chamber for controlling the flow of the brake fluid from the servo chamber to the low pressure source;
a servo pressure sensor which detects the servo pressure;
a plurality of wheel cylinders which apply a braking force to respective corresponding vehicle wheels in response to respective wheel cylinder pressures; and
a brake actuator disposed between the master cylinder and the plurality of wheel cylinders and structured so that a plurality of target wheel cylinder pressures which are the wheel cylinder pressures in response to a desired braking force are individually applicable to the respective wheel cylinders based on the master pressure of the master cylinder, the brake actuator including a holding control valve and a second pressure decreasing control valve both of which are provided at each corresponding wheel cylinder, wherein,
the vehicle control device
controls the pressure increasing control valve and the first pressure decreasing control valve so that the servo pressure detected by the servo pressure sensor becomes a target servo pressure;
while a brake operating member is not operated and a wheel cylinder pressure supplying control is executed to supply the target wheel cylinder pressures to the respective wheel cylinders individually, sets a target servo pressure maximum value to a first predetermined target servo pressure, the target servo pressure maximum value being a maximum value of the target servo pressure, the first predetermined target servo pressure being one of a plurality of set values, the plurality of set values being values smaller than a maximum output pressure of the servo pressure generating device;
calculates a target wheel cylinder pressure maximum value which is a maximum value among the target wheel cylinder pressures to be applied to the respective wheel cylinders; and
sets the target servo pressure, when the target wheel cylinder pressure maximum value is lower than a previous target pressure, so that the target servo pressure increases at a lower limit inclination until the target servo pressure reaches the target servo pressure maximum value, the previous target pressure being a target pressure which is calculated at a control cycle of last time, the control cycle being a cycle which is repeatedly executed to set a target pressure, the lower limit inclination being a speed inclination corresponding to a minimum output per unit time of the servo pressure generating device.

2. The vehicle control device according to claim 1 , wherein, the vehicle control device sets the target servo pressure so that the target servo pressure increases at the lower limit inclination until the target servo pressure reaches the target servo pressure maximum value, when an increase inclination of the target wheel cylinder pressure maximum value is smaller than the lower limit inclination.

3. The vehicle control device according to claim 1 , wherein, the vehicle control device renews the target servo pressure maximum value to a second predetermined target servo pressure from the first predetermined target servo pressure when the target wheel cylinder pressure maximum value is equal to or more than the first predetermined target servo pressure, the second predetermined target servo pressure being one of a plurality of values that is larger than the first predetermined target servo pressure.

4. The vehicle control device according to claim 1 , wherein,
the vehicle control device sets the target servo pressure to the target wheel cylinder pressure maximum value when an increase inclination of the target wheel cylinder pressure maximum value is equal or larger than the lower limit inclination.

5. The vehicle control device according to claim 1 , wherein,
the vehicle control device maintains the target servo pressure at the target servo pressure maximum value when the target servo pressure has reached the target servo pressure maximum value and the target wheel cylinder pressure maximum value has not exceeded the target servo pressure maximum value.

Assignees

• Advics Co Ltd
• Toyota Motor Co Ltd

Inventors

• Ninoyu Masaki
• Okano Takahiro
• Kamiya Yusuke
• Nakata Daisuke
• Komazawa Masaaki

Classifications

• B60T13/146

  Part of the system directly actuated by booster pressure · CPC title

• B60T8/489

  using separate traction control modulators · CPC title

• B60T13/745

  acting on a hydraulic system, e.g. a master cylinder · CPC title

• B60T7/042

  by electrical means, e.g. using travel or force sensors · CPC title

• B60T8/172

  Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters {(B60T8/17551 takes precedence)} · CPC title