Patent · US Expired

Transmission with a first-stage hydrostatic mode and two hydromechanical stages

US4168637A · kind A · utility

13Cited by
7References
31Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 15, 1977
Grant dateSep 25, 1979
Priority date
Expiry dateApr 15, 1997

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H2037/107
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A power transmission having two planetary assemblies, each having at least one carrier with planet gears, at least one sun gear, and at least one ring gear. A speed-varying module is connected in driving relation to the input shaft and in driving relationship to the sun gear or gears of the first planetary assembly. The speed-varying means may comprise a pair of hydraulic units hydraulically interconnected so that one serves as a pump while the other serves as a motor and vice versa, one of the units having a variable stroke and being connected in driving relation to the input shaft, the other unit, which may have a fixed stroke, being connected in driving relation to the sun gear. The input shaft is also connectable by a first clutch to a carrier of the first planetary assembly and by a second clutch to a sun gear of the second planetary assembly. A brake grounds the first carrier in the first range and in reverse and causes drive to be delivered to the output through a ring gear of the first planetary assembly in a hydrostatic mode. The carrier of the second planetary assembly being connected in driving relationship to that ring gear, and in all ranges these two elements transmit…

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