Patent ID: 8197374
Filing Date: 2012-06-12
Classification: F16D,F16H,Y10T

Abstract:
1. An automatic transmission, comprising: a transmission case storing a transmission mechanism therein, the transmission case comprising a body case and an end cover closing an opening at an end portion of the body case; a multi-plate brake to brake a specified rotational element of the transmission mechanism, the multi-plate brake including a plurality of frictional plates, a piston to press the plural frictional plates, a piston cylinder member comprising a cylinder in which the piston slides, and an oil-pressure chamber formed between the piston and the cylinder, the oil-pressure chamber biasing the piston toward the frictional plates with an oil pressure supplied thereto; and a valve body to supply the oil pressure to the oil-pressure chamber, the valve body being provided in the vicinity of an outer periphery of the piston cylinder member, wherein said piston cylinder member includes a connection portion which is formed integrally with the piston cylinder member and separately from said body case and said end cover of the transmission case, the connection portion projecting toward said valve body and including an oil passage to supply the oil pressure from said valve body to said oil-pressure chamber therein, the oil passage extending straightly in a radial direction of the automatic transmission over an entire length thereof from the valve body to the oil-pressure chamber.