PORTLESS TYPE MASTER CYLINDER DEVICE WITH INTAKE VALVE AND FLOW RESISTING MEANS BETWEEN PRESSURE CHAMBER AND RESERVOIR CHAMBER

摘要

ABSTRACT OF THEDISCLOSUREIn this portless type master cylinder device, a cylinder bore is formedin a body thereof, and a piston member is fitted in the cylinder bore and isslidably movable from an initial axial position therein and defines a pressurechamber on its one side and a reservoir chamber on its other side incooperation with the cylinder bore. An intake valve communicates betweenthe cylinder chamber and the reservoir chamber, and is opened when thepiston member is in its initial axial position while it is closed when the pistonmember moves through more than a determinate relatively small axialdistance from its initial axial position. Intermediately along the fluid flowpath between the intake valve and the reservoir chamber, there is provided ameans for presenting a relatively high flow resistance to flow of fluid in thedirection from the intake valve to the reservoir chamber. Thereby, in thedynamic operational mode, the stroke of the piston member has a muchreduced inactive initial stroke portion, as compared with other portless typemaster cylinder devices, and the operational feeling of the master cylinderdevice is greatly improved.