Patent · US Expired

Drive system for machines and vehicles, with a hydraulic and mechanical transmission arranged thereafter

US4939954A · kind A · utility

19Cited by
13References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 15, 1989
Grant dateJul 10, 1990
Priority date
Expiry dateFeb 15, 2009

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T74/19163
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A drive system for machines and vehicles with a hydraulic and mechanical transmission arranged thereafter having a driving motor and a control member which can continuously vary the speed of the motor. A hydraulic converter also controlled by a control member dependent upon the speed of the driving motor and the running pressure of the motor is also provided, in which a transmission arranged after the converter and a shifting mechanism is connected to an electronic control circuit so that an operating element for shifting gears of the transmission may achieve a comfortable shifting behavior for the transmission. Shifting from a high gear to a low gear will occur only under the following conditions: (a) before shifting, the output speed of the hydraulic converter is below a certain predetermined value, and (b) before shifting, the transmission ratio of the converter reaches a specific minimum value caused by the working pressure of the motor.

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