Patent ID: 6725760
Filing Date: 2004-04-27
Classification: B60T

Abstract:
A brake booster comprising:a housing with an interior separated into at least a first chamber and a second chamber by a wall connected to a peripheral surface on a cylindrical body of a hub, said cylindrical body having axial bore that extends from a first end to a second end for retaining a control valve that sequentially connects said first chamber with said second chamber to provide for the equalization of fluid pressure between said first and second chambers during a first mode of operation and interrupting communication between said first and second chambers while connecting said second chamber to a surrounding environment to allow air to enter into said second chamber and create a pressure differential across said wall in response to an operational signal to defining a second mode of operation, said pressure differential acting on said wall to develop an output force that is communicated to said hub and after overcoming a return spring moves an output push rod to provide a master cylinder with an operational input to effect a brake application, said cylindrical body being characterized by: a radial flange that extends from said first end; a ledge located adjacent said radial flange; an annular shoulder that extends from said peripheral surface; and a groove located between the ledge and shoulder, said groove having a depth adjacent said shoulder that is approximately equal to the height of the shoulder above said peripheral surface, said groove having a side wall that transitions from said shoulder to said ledge; and said wall being characterized by: a metal disc with an axial flange that extends from a first end and a diaphragm, said diaphragm having a lip with an annular slot therein for receiving said axial flange of said metal disc, said lip being located and retained on said ledge by a portion of said axial flange being deformed into said groove such that an axial seal is defined between said lip and said flange to prevent communication from said first chamber to said second chamber along the peripheral surface of said cylindrical body.