Oblon, Spivak, McClelland, Maier & Neustadt
Hydraulic control apparatus for belt-and-pulley type continuously variable transmission, incorporating means for optimizing belt tensioning pressure
 A hydraulic control apparatus for a vehicle continuously variable transmission including a pressure regulating valve having a valve spool which operates depending upon a determined current speed ratio of the transmission and a currently detected required output of the vehicle engine, to generate a controlled belt tensioning pressure for controlling the tension of a transmission belt at a required minimum level. The apparatus further includes a device responsive to an electric signal, for generating a pilot pressure to be applied to the valve, and an electronic control device for calculating a basic output pressure of the valve, based on the current speed ratio and the currently required output, according to a stored predetermined relationship among these two parameters and the basic output pressure, to determine the electric signal so that the belt tensioning pressure coincides with the optimum value. 
Toyota Jidosha Kabushiki Kaisha
F F
F16H F16H
inventional inventional
Takashi Nobuyuki Yuji Katsumi
Hayashi Kato Hattori Kouno