RUNNING CONTROL SYSTEM FOR VEHICLE

• US 20150191172A1
• Filed: 08/08/2012
• Published: 07/09/2015
• Est. Priority Date: 08/08/2012
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Kim, Jonggap
• Granted Patent: US 9,604,644 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 10/115 with planetary gears
• CPC Class Codes: B60W 10/18 including control of braking systems
• CPC Class Codes: B60W 10/184 with wheel brakes
• CPC Class Codes: B60W 2030/1809 Without torque flow between driveshaft and engine, e.g. with clutch disengaged or transmission in neutral
• CPC Class Codes: B60W 30/18072 Coasting
• CPC Class Codes: B60W 30/18136 Engine braking
• CPC Class Codes: F16D 48/02 Control by fluid pressure
• CPC Class Codes: Y02T 10/60 Other road transportation technologies with climate change mitigation effect

Abstract

A running control system for vehicles is provided to reduce uncomfortable feeling during coasting by adjusting a braking force. The running control system is applied to a vehicle having a braking device adapted to generate a braking force according to an operation of a driver irrespective of an engagement state of the engagement elements disposed between a prime mover and drive wheels. The running control system comprises a controller that applies a braking force of the prime mover to the drive wheels by bringing the engagement elements into engagement to enable torque transmission between the prime mover and the drive wheels, when the braking force of the braking device is eliminated by aborting an operation of the braking device during coasting while disengaging the engagement elements to interrupt torque transmission between the prime mover and the drive wheels.

Claims

1. A running control system for a vehicle having an engagement element that is disposed between a prime mover and drive wheels to selectively enable power transmission therebetween, and a braking device that is adapted to generate a braking force according to an operation of a driver irrespective of an engagement state of the engagement element, comprising:

a controller that is configured to apply a braking force of the prime mover to the drive wheels by bringing the engagement element into engagement to enable torque transmission between the prime mover and the drive wheels, if the braking device is operated and then the braking force of the braking device is eliminated by aborting an operation of the braking device during coasting of the vehicle while disengaging the engagement element to interrupt torque transmission between the prime mover and the drive wheels.

2. The running control system as claimed in claim 1,

wherein the controller is further configured to apply the braking force of the prime mover to the drive wheels by bringing the engagement element into engagement to enable torque transmission between the prime mover and the drive wheels, when deceleration demand of the driver based on a braking operation exceeds a predetermined demand.

3. The running control system as claimed in claim 1,

wherein the engagement element includes at least a first engagement element and a second engagement element;

and

further comprising a transmission that is disposed on a powertrain for transmitting power from the prime mover to the drive wheels, and that is adapted to establish a gear stage by bringing the first engagement element and the second engagement element to enable power transmission between the prime mover and the drive wheels.

4. The running control system as claimed in claim 2,

wherein the deceleration demand of the driver based on a braking operation is calculated based on a depressing force applied to a brake pedal.

5. The running control system as claimed in claim 3, further comprising:

wherein the coasting includes a running condition achieved by bringing any one of the first and the second engagement elements into disengagement; and

wherein the controller is further configured to bring into engagement any one of the first and the second engagement elements being in disengagement.

6. The running control system as claimed in claim 2,

wherein the engagement element includes at least a first engagement element and a second engagement element;

and

further comprising a transmission that is disposed on a powertrain for transmitting power from the prime mover to the drive wheels, and that is adapted to establish a gear stage by bringing the first engagement element and the second engagement element to enable power transmission between the prime mover and the drive wheels.

7. The running control system as claimed in claim 6, wherein the deceleration demand of the driver based on a braking operation is calculated based on a depressing force applied to a brake pedal.

8. The running control system as claimed in claim 7, further comprising:

wherein the coasting includes a running condition achieved by bringing any one of the first and the second engagement elements into disengagement; and

wherein the controller is further configured to bring into engagement any one of the first and the second engagement elements being in disengagement.