Patent · US Expired

On-demand four-wheel drive transmission

US5989146A · kind A · utility

26Cited by
27References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 4, 1998
Grant dateNov 23, 1999
Priority date
Expiry dateFeb 4, 2018

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB60K23/0808
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

A transmission for a four-wheel drive vehicle having a multi-speed geartrain and power transfer mechanism incorporated into a common housing assembly. The multi-speed geartrain includes a input shaft, a mainshaft, and a plurality of constant-mesh gearsets arranged for selectively coupling the mainshaft to the input shaft for driven rotation at various speed ratios. The mainshaft can be selectively coupled to the power transfer mechanism for establishing two alternative power transmission routes. In particular, a synchronized range shift mechanism is provided for establishing a high-range transmission route and a low-range transmission route from the mainshaft to a primary driveline to define a two-wheel drive mode. A portion of the drive torque delivered to the primary driveline can be transferred automatically through a transfer clutch to the secondary driveline to establish an on-demand four-wheel drive mode. As an option, a mode clutch can be provided for permitting the secondary driveline to be locked to the primary driveline for establishing a part-time four-wheel drive mode.

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