Patent · US Expired

Hydrostatic transmission with automatic displacement shifter

US4040254A · kind A · utility

8Cited by
3References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 25, 1976
Grant dateAug 9, 1977
Priority date
Expiry dateMar 25, 1996

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H61/46
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A hydrostatic transmission system is provided which is particularly well adapted for use in driving vehicles employing skid-steer drives. In the system disclosed two independent hydrostatic transmissions, each employing a variable displacement motor are utilized; and a pressure responsive valve is employed to sense the magnitude of the load on each of the motors and to permit shifting the motors from minimum displacement toward maximum upon the sensing of a load in excess of a predetermined valve. The variable displacement motors of the system are configured to create forces during operation tending to urge the motors to maximum displacement, and the pressure responsive valve operates to bias the motors to minimum displacement when they are loaded at a magnitude less than the predetermined valve.

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