Patent · US Expired

System for controlling transmission ratio of transmission for automotive vehicles

US4480504A · kind A · utility

5Cited by
7References
18Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 12, 1981
Grant dateNov 6, 1984
Priority date
Expiry dateMay 12, 2001

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H2015/383
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

The transmission ratio of an infinitely variable transmission for automotive vehicles is controlled by a system including a hydraulic servo. The servo mechanism including an actuator which is driven by a line pressure to actuate the transmission and a spool having one end to which a signal pressure responsive to both throttle opening responsive pressure and vehicle speed responsive pressure is applied counteractingly against a spring. The spool provides a control valve function for the driving fluid pressure to the actuator. In response to signal pressure change to the spool the actuator is actuated in such direction that the transmission ratio is decreased or increased. The signal pressure is produced by a compensation valve due to a throttle opening responsive pressure and vehicle speed responsive pressure, e.g. governor pressure.

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