Vehicle control device

• US 9,694,794 B2
• Filed: 07/31/2014
• Issued: 07/04/2017
• Est. Priority Date: 07/31/2013
• Status: Active Grant

• Current Assignee: Advics Company Limited (Aisin Corp.)
• Original Assignee: Advics Company Limited (Aisin Corp.)
• Inventors: Ishida, Yasuhito
• Primary Examiner(s): Black, Thomas G
• Assistant Examiner(s): LEWANDROSKI, SARA J
• Application Number:
  US14/909,330
• Publication Number:
  US 20160185327A1
• Time in Patent Office: 1,069 Days
• CPC Class Codes: B60T 7/12 for automatic initiation; for initiation not subject to will of driver or passenger limiting speed of vehicles other than rail vehicles B60K31/00
• CPC Class Codes: B60T 8/175 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 Class Codes: B60T 8/3205 acceleration B60T8/34, B60T8/52, B60T8/54, B60T8/56, B60T8/58, B60T8/72, B60T8/86, B60T8/88 take precedence
• CPC Class Codes: B60W 10/04 including control of propulsion units
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/18 including control of braking systems
• CPC Class Codes: B60W 10/184 with wheel brakes
• CPC Class Codes: B60W 10/188 hydraulic brakes
• CPC Class Codes: B60W 2300/185 Off-road vehicles
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 2540/106 Rate of change
• CPC Class Codes: B60W 2540/215 Selection or confirmation of options
• CPC Class Codes: B60W 2552/15 Road slope, i.e. the inclination of a road segment in the longitudinal direction
• CPC Class Codes: B60W 2710/18 Braking system
• CPC Class Codes: B60W 2720/10 Longitudinal speed
• CPC Class Codes: B60W 30/18063 Creeping
• CPC Class Codes: B60W 30/18172 Preventing, or responsive to skidding of wheels
• CPC Class Codes: B60W 30/182 Selecting between different operative modes, e.g. comfort and performance modes
• CPC Class Codes: B60W 30/188 Controlling power parameters of the driveline, e.g. determining the required power

Abstract

To enable control of vehicle speed according to the intentions of a driver by a simpler operation. When a vehicle body speed rapidly decreases and becomes lower than a brake target threshold speed, the brake target threshold speed is decreased in conformity with the vehicle body speed. This prevents the increase of the vehicle body speed toward the brake target threshold speed such that a vehicle accelerates regardless of a brake being in operation because the brake target threshold speed is set at a higher value than the vehicle body speed. Accordingly, the vehicle body speed decelerates by a simpler operation while being able to prevent the vehicle from accelerating against the intentions of a driver and being able to control the speed of the vehicle according to the intentions of the driver.

Claims

1. A vehicle control device applied to a vehicle including a service brake configured to generate wheel cylinder pressure in accordance with brake operation to generate braking force at each wheel, and automatically increase the wheel cylinder pressure to automatically control the braking force of the wheel, the device comprising:

an electronic control unit configured to set target speed of vehicle body speed of the vehicle and execute off-road support control of driving force control to cause the vehicle body speed to approach the target speed;

wherein

the electronic control unit is configured to set brake target threshold speed as the target speed and generate the braking force when the vehicle body speed exceeds the target speed to cause the vehicle body speed to approach the target speed, and

the electronic control unit decreases the brake target threshold speed in conformity with the vehicle body speed when the off-road support control is executed and the vehicle body speed is decreased to become lower than the brake target threshold speed by braking force generated by the brake operation, and

the electronic control unit sets the brake target threshold speed in accordance with an accelerator open degree and limiting acceleration of the vehicle to an upper limit value when the vehicle body speed increases in accordance with the accelerator operation, and the vehicle body speed is increased so as not to exceed the brake target threshold speed.

2. The vehicle control device according to claim 1, wherein the electronic control unit is configured to set the brake target threshold speed with an increasing grade having a preliminarily set speed upper limit value as an upper limit guard.

3. The vehicle control device according to claim 2, wherein, when accelerator restoring operation is performed and an accelerator restoring amount per unit time period is larger than a threshold, the electronic control unit is configured to set the brake target threshold speed with larger deceleration of the vehicle body speed in comparison to a case where the accelerator restoring amount is smaller than the threshold.

4. The vehicle control device according to claim 1, wherein, when the accelerator off state by the accelerator restoring operation, for a predetermined period after the accelerator off state, the electronic control unit is configured to set the brake target threshold speed with larger deceleration of the vehicle body speed than deceleration after elapse of the predetermined period.

5. The vehicle control device according to claim 1, wherein, when the brake operation is performed, the electronic control unit is configured to set the brake target threshold speed with larger deceleration of the vehicle body speed in comparison to a case where the brake operation is not performed.

6. The vehicle control device according to claim 1, wherein, when accelerator restoring operation is performed and an accelerator restoring amount per unit time period is larger than a threshold, the electronic control unit is configured to set the brake target threshold speed with larger deceleration of the vehicle body speed in comparison to a case where the accelerator restoring amount is smaller than the threshold.