Control process and control arrangement for a continuously variable speed transmission

US5540632A · kind A · utility

Assignee

• Dr. Ing. h.c. F. Porsche AG · DE

Inventors

• Patric Lardy · Weil der Stadt, DE
• Willi Seidel · Lambach, DE
• Heinz Stehle · Marloffstein, DE
• Joseph Petersmann · Wimsheim, DE

Key dates

• Filing date: Apr 7, 1995
• Grant date: Jul 30, 1996
• Expiry date: Apr 7, 2015

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F16H2061/0015
• WIPO field: Mechanical elements
• WIPO sector: Mechanical engineering

Abstract

This invention provides a method and apparatus for controlling a continuously variable speed transmission connected with an internal-combustion engine according to one or several characteristic control curves. A transmission ratio of the transmission is automatically set according to the position of a power control element. In order to be able to operate the internal-combustion at its consumption-optimal point, a "constant driving method" which requires only a low reserve of tractive force is detected, and transmission ratio is adjusted in response thereto, so that the internal-combustion engine is operated in its point of the lowest specific fuel consumption for the existing operating point of the vehicle.