Patent · US Expired

Control system for automatic transmission for vehicle

US5931762A · kind A · utility

7Cited by
6References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 20, 1998
Grant dateAug 3, 1999
Priority date
Expiry dateAug 20, 2018

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H2059/506
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

When slipping is generated during the upshifting from a first gear shift stage to a second gear shift stage on ice or the like, a control for prohibiting the upshifting from the second gear shift stage to a third gear shift stage can be carried out precisely. A control system is designed so that when a slipping state is detected on ice having a lower road surface friction coefficient by a slipping state determining device, the upshifting of an automatic transmission from a second gear shift stage to a third gear shift stage is prohibited. In this control system, the time required for the upshifting from a first gear shift stage to the second gear shift stage is measured. If such time is shorter than a first predetermined time, it is determined that a slipping has been generated during the upshifting, and the upshifting from the second gear shift stage to the third gear shift stage is prohibited for a second predetermined time. Thus, even when the determination of the slipping state by the slipping-state determining device is not in time, the further upshifting of the automatic transmission is prohibited. Therefore, it is possible to reliably avoid the carrying-out of undesirable up…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.