Patent · US Expired

Control method for protecting a viscous converter clutch in a motor vehicle drivetrain

US4828082A · kind A · utility

6Cited by
4References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 19, 1988
Grant dateMay 9, 1989
Priority date
Expiry dateFeb 19, 2008

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H61/143
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

Potentially damaging operation of a viscous converter clutch (VCC) is detected in relation to the slippage thereacross. The slippage is compared with a reference slip value indicative of excessive VCC slippage to develop a net overslip indicator. The value of the net overslip indicator changes in the direction of a first limit value so long as the detected slip is at least as great as the reference slip, and in the direction of a second limit value so long as the detected slip is less than the reference slip. When the net overslip indicator reaches the first limit value, the friction clutch is disengaged to release the VCC. According to a first embodiment, the transmission fluid temperature at the time of such deactivation is measured and stored, and the VCC is reactivated when transmission fluid temperature falls below the stored temperature, assuming other criteria for activation are also met. According to a second embodiment, the VCC is reactivated a predetermined time after its deactivation and measurement of the transmission fluid temperature is not required.

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