Vehicle control device

• US 9,347,500 B2
• Filed: 10/13/2010
• Issued: 05/24/2016
• Est. Priority Date: 10/14/2009
• Status: Active Grant

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Okuda, Tadashi
• Primary Examiner(s): Hansen, Colby M
• Assistant Examiner(s): FLUHART, STACEY A
• Application Number:
  US13/501,302
• Publication Number:
  US 20120199437A1
• Time in Patent Office: 2,050 Days
• Field of Search: 192/85.57, 192/85.63
• US Class Current: 1/1
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60K 6/547 the transmission being a stepped gearing
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/40 Controlling the engagement or disengagement of prime movers, e.g. for transition between prime movers power-up or power-down of the driveline B60W30/192
• CPC Class Codes: B60W 2510/0208 Clutch engagement state, e.g. engaged or disengaged
• CPC Class Codes: F16D 25/087 the clutch being actuated by the fluid-actuated member via a diaphragm spring or an equivalent array of levers F16D25/085, F16D25/086 take precedence
• CPC Class Codes: F16D 2500/1026 Hydraulic
• CPC Class Codes: F16D 2500/10412 Transmission line of a vehicle
• CPC Class Codes: F16D 2500/1066 Hybrid
• CPC Class Codes: F16D 2500/3024 Pressure
• CPC Class Codes: F16D 2500/3026 Stroke
• CPC Class Codes: F16D 2500/3166 Detection of an elapsed period of time
• CPC Class Codes: F16D 2500/525 Improve response of control system
• CPC Class Codes: F16D 2500/70406 Pressure
• CPC Class Codes: F16D 2500/7041 Position
• CPC Class Codes: F16D 48/04 providing power assistance
• CPC Class Codes: F16D 48/062 of a clutch system with a plurality of fluid actuated clutches
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles

Abstract

A first clutch CL1 is disposed between engine Eng and left and right rear wheels RL, RR, and control of disengaging first clutch CL1 is performed by setting line pressure PL as an original pressure and executing F/B control of a piston stroke position. In this FR hybrid vehicle, when disengaging first clutch CL1, line pressure increase control to increase line pressure PL to a value higher than a reference line pressure in advance is started at least before a piston pressure reaches the reference line pressure, and line pressure PL is returned to the reference line pressure when the piston pressure is reduced during this disengagement operation.

Claims

1. A control apparatus of a vehicle including a driving source and an automatic transmission that is driven and controlled by a hydraulic pressure produced from a line pressure as an original pressure, the control apparatus comprising:

a hydraulic clutch disposed between the driving source and the automatic transmission;

a clutch hydraulic actuator including a piston;

a clutch hydraulic control valve configured to produce a piston pressure from the line pressure as the original pressure, the piston pressure being applied to the piston, wherein the piston pressure is limited substantially to the line pressure;

a clutch control section configured to operate the piston of the clutch hydraulic actuator to make a stroke to disengage the hydraulic clutch by controlling the piston pressure as a clutch disengagement hydraulic pressure such that an actual piston stroke position is conformed with a target position;

an AT control section configured to determine a reference line pressure on the basis of a necessary hydraulic pressure to ensure an operation of the automatic transmission; and

a clutch disengagement control section, which controls disengagement of the hydraulic clutch, configured to;

upon receiving a clutch disengagement command and disengaging the hydraulic clutch, start line pressure increase control to increase the line pressure to a value higher than the reference line pressure at least before the piston pressure reaches the reference line pressure, and thereby allow the piston pressure to exceed the reference line pressure; and

reduce the line pressure when the piston pressure is reduced during an operation of disengagement of the hydraulic clutch.

2. The control apparatus of a vehicle as claimed in claim 1, wherein the clutch disengagement control section is configured to set a timing of increasing the line pressure within a predetermined time width that straddles a timing of starting to increase the piston pressure.

3. The control apparatus of a vehicle as claimed in claim 2, wherein the clutch disengagement control section is configured to set the timing of increasing the line pressure in conformity with the timing of starting to increase the piston pressure.

4. The control apparatus as claimed in claim 1, wherein the AT control section is configured to determine the reference line pressure independently of operation of the hydraulic clutch.