Patent · US Expired

Hydraulic control system for continuously variable transmission

US4718308A · kind A · utility

33Cited by
12References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 29, 1985
Grant dateJan 12, 1988
Priority date
Expiry dateMar 29, 2005

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H61/66259
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

A control arrangement for a continuously variable transmission includes an electronic control system and a hydraulic control system. In the hydraulic control system three separate electromechanical control assemblies are used to regulate the pressure in the secondary sheave chamber (to hold the belt tension), the fluid flow to and from the primary sheave chamber (to regulate the CVT ratio), and to control the pressure in the apply line for the clutch chamber. The pump assembly of the hydraulic control system has a first output connection for providing fluid at line (high) pressure in the main line, and a second, low pressure output connection for providing fluid at a low pressure to satisfy the clutch cooling requirements. The high pressure and low pressure systems are essentially independent of each other.

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