Patent · US Expired

Transmission for four-wheel drive vehicle

US6254506A · kind A · utility

1Cited by
9References
25Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 24, 1999
Grant dateJul 3, 2001
Priority date
Expiry dateNov 24, 2019

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB60K17/3465
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

A motor vehicle transmission has a differential assembly (17) in which one input, sun gear (39), of an epicyclic gear train can be selectively coupled by a sleeve (59) through a viscous coupling (55) to either an input, i.e. annulus gear (31), or to another output, i.e. carrier (36). Coupling the sun gear to the annulus gear gives a low resistance mode of operation and coupling the sun gear to the carrier gives a high resistance mode of operation. A locked mode where the annulus is locked to the sun gear is also described, together with a free mode where the viscous coupling is disconnected from both the annulus gear and the carrier. The sleeve is lined to the control of a range change gearbox to select the low resistance mode when a high range is selected for on-road use and a high resistance mode is selected when a low range is selected for off-road use.

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