Vehicle transmission system with coast controls

US6939268B2 · kind B2 · utility

Assignee

• ZF Meritor, LLC · US

Inventors

• James DeVore · Laurinburg, US
• Charles E. Allen, Jr. · Rochester Hills, US
• Winfried Sturmer · Euerbach, DE
• Karl-Fritz Heinzelmann · Meckenbeuren, DE
• Ludger Ronge · Eriskirch, DE
• Loren Christopher Dreier · Southern Pines, US
• Robert Sayman · Eriskirch, DE
• Ronald Muetzel · Southern Pines, US
• Muneer AbuSamra · Southern Pines, US

Key dates

• Filing date: Nov 4, 2003
• Grant date: Sep 6, 2005
• Expiry date: Nov 4, 2023

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F16H2306/54
• WIPO field: Transport
• WIPO sector: Mechanical engineering

Abstract

A vehicle transmission system includes a transmission component that has an engaged condition where torque can be transferred from a vehicle engine to a drive component, and a non-engaged condition where torque is prohibited from being transferred to the drive component. A controller generates control signals to control whether the transmission component is in the engaged or non-engaged condition. The controller also identifies when a vehicle start maneuver is a coast start based on vehicle conditions existing just prior to or during the vehicle start maneuver. When a coast start is identified, the controller generates a control signal to either disengage the transmission component or to maintain the transmission component in the non-engaged condition until engine speed generally matches transmission component speed. The controller can directly control engagement by automatically actuating a movable transmission member or can indirectly control engagement by controlling engine speed. Once engine speed and transmission component speed are generally within a common speed range during coasting, the transmission component is engaged.