Patent · US Expired

Controller and control method for continuously variable transmission

US5871416A · kind A · utility

12Cited by
5References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 7, 1997
Grant dateFeb 16, 1999
Priority date
Expiry dateMar 7, 2017

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H2061/6616
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

In a continuously variable transmission (CVT) for a vehicle wherein a belt of V-shaped cross-section is looped around a drive pulley and a driven pulley respectively having grooves of identical shape to this belt, and the width of the groove of each pulley is varied according to a supplied oil pressure, an oil pressure when an accelerator pedal is released is maintained at or above a predetermined value. The oil pressure is controlled according to a torque input to the drive pulley, and the input torque varies according a depression amount of the accelerator pedal. As a result, the speed change ratio easily varies due to insufficient oil pressure when the accelerator pedal is released. This invention stops decline of oil pressure when the accelerator is released, and thereby prevents variation of the speed change ratio due to release of the accelerator pedal. This is especially useful when the speed change ratio of the transmission has been fixed by the driver in a manual speed change mode.

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