Patent · US Expired

Variable speed transmission

US5137129A · kind A · utility

1Cited by
4References
2Claims
0Family size

Inventor

Key dates

Filing dateJun 3, 1991
Grant dateAug 11, 1992
Priority date
Expiry dateJun 3, 2011

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16D31/08
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

Utilizing the characteristic that a hydraulic pump, such as a gear pump, having the fluid flow from its outlet restricted will tend from the increasing internal pressure to rotate with the input shaft, a variable speed transmission is designed which includes such a hydraulic pump having a rotating input shaft coincident with the input shaft of the transmission, a fluid flow regulating unit between the fluid outlet and fluid inlet of the pump, and an output shaft connected to the external housing of the pump. The fluid flow regulation unit, which includes a first fluid containing chamber connected to the pump outlet and a second fluid containing chamber connected to the pump inlet, adjustably varies fluid flow between the two chambers. A cylindrical sleeve member, having a plurality of perforations interconnecting the two fluid containing chamber, and a blocking piston slidably installed within the cylindrical sleeve permit variation between no and full fluid flow. The blocking piston, extending concentrically within an output stem of the enclosing transmission housing, is tranversely penetrated by a pin so that the pin ends extend through a pair of opposing longitudinal slots forme…

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