Patent · US Expired

Hydrostatic transmission center section

US5218886A · kind A · utility

29Cited by
11References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 24, 1991
Grant dateJun 15, 1993
Priority date
Expiry dateMay 24, 2011

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T74/2186
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

An integrated hydrostatic transaxle having a common housing for a hydrostatic transmission and a pair of oppositely-extending differentially-connected axles to have the common housing provide a common sump therefor and with a specifically-shaped center section interconnecting the pair of hydraulic displacement units constituting the hydrostatic transmission. The center section is a unitary member separate from the common housing, with the exterior thereof exposed to the common sump. The center section has passages and arcuate ports which are interconnected by certain of said passages and which are located whereby the center section may be cast to minimize any machining required to finish the center section. Such casting can result in a porous center section with possible leakage from a passage having high pressure fluid. However, such leakage is not a problem since the leakage would not be through the wall of the common housing but to the common sump within the common housing which is at atmospheric pressure because of the center section being separate from the common housing.

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