Downshift control apparatus for automatic power transmission
Kick-down circuit for automatic change-speed transmissions
Automatic transmission with electrical override
Shift device for hydraulic control system for automatic transmission Patent #: 4467675
ApplicationNo. 06/740561 filed on 06/03/1985
ExaminersPrimary: Braun, Leslie A.
Assistant: Novais, David
Attorney, Agent or Firm
International ClassesF16H 59/18 (20060101)
F16H 59/20 (20060101)
F16H 63/00 (20060101)
F16H 63/44 (20060101)
Foreign Application Priority Data1984-06-05 JP
AbstractA vehicle automatic transmission including a torque converter, a multiple stage transmission gear mechanism connected with the torque converter and a hydraulic control circuit for automatically selecting one of gear stages of the transmission gear mechanism. The hydraulic control circuit includes a kick-down control device which functions to shift down the gear mechanism when the engine control foot pedal is substantially fully depressed. Depending on the vehicle running condition, the kick-down control device may shift down the gear mechanism by two gear stages. The hydraulic circuit includes control hydraulic circuit which functions to shift down the gear mechanism at first by one gear stage and then by a further one stage. For the purpose, relay valves are provided in kick-down control lines to lower stage shift valves.