Patent · US Expired

Vehicular automatic transmission control system with gear shift inhibitor

US4846020A · kind A · utility

4Cited by
16References
1Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 27, 1984
Grant dateJul 11, 1989
Priority date
Expiry dateMar 27, 2004

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H2061/026
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A vehicular automatic transmission control system comprising: a hydraulic control circuit including a hydraulic pressure source, a pressure regulator valve for producing a line pressure by regulating the oil pressure supplied from the pressure source, a number of shift valves for selectively engaging and releasing friction members of the automatic transmission according to operating conditions of a vehicle such as vehicle speed and throttle opening rate, and a solenoid valve blocking switching operation of a highest shift gear toward a highest gear position of the transmission; and an electronic control circuit for controlling on- and off-ranges of the solenoid valve, including a manual mode switch for setting the control either in a highest speed non-cancel mode permitting shifts to the highest gear position or a highest speed cancel mode inhibiting shifts to the highest gear position and forcibly effecting a downshift when selected during operation in the highest gear position, and a vehicle speed sensor; characterized in that: the electronic control circuit is arranged to nullify setting of the highest gear cancel mode by the manual mode switch at a vehicle speed higher than a p…

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