Patent · US Active

Work vehicle having hydraulic stepless speed changing apparatus

US8007403B2 · kind B2 · utility

5Cited by
1References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 4, 2008
Grant dateAug 30, 2011
Priority date
Expiry dateFeb 27, 2030

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H59/54
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A work vehicle includes a hydraulic stepless speed changing apparatus and a gear type speed changing apparatus operable to receive output from the hydraulic stepless speed changing apparatus to convert it into a plurality of stages of speed. A return oil passage connected to a high-pressure side circuit of the hydraulic stepless speed changing apparatus is connected to a hydraulic tank. The return oil passage incorporates an unload valve and a throttle valve, between which an operably coupling mechanism is provided. This operably coupling mechanism switches over the unload valve to an unload condition in response to an operational displacement of a brake operating member for operating a brake to its braking side.

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