Brake system proportioning valve

Claim 2

A vehicular braking system, comprising: a. means defining a fluid operated braking assembly having a graduated supply of pressure and having at least first and second braking portions, each portion having differential mechanical capability and each portion being subject to differential linear deceleration effects, and b. means controlling fluid communication to each of said first and second portions so as to proportion fluid pressure therebetween below a predetermined supply pressure in a manner compensating for said mechanical differential between said portions and to proportion fluid pressure at a fixed ratio between said portions when above said predetermined supply pressure by communicating an intensified fluid pressure to one of said portions to compensate for linear deceleration effects, said control means having pressure intensification means including a body of trapped fluid acted upon to communicate an intensified pressure to said one portion, said control means having a return channel for relieving pressure in said one portion upon a decrease in said supply pressure, said channel having a restriction therein to provide a delay in the return of fluid from said one portion whereby the control means is cushioned against abrupt action.

Claim 3

In a vehicle hydraulic brake system having a master cylinder and plurality of brake cylinders, a pressure regulating device adapted to be interposed between the master cylinder and at least one brake cylinder, said device including a housing having an inlet, an outlet, and a bore providing communication between said inlet and outlet, a pressure proportioning piston positioned in said bore and movable toward said outlet to generate a pressure at said outlet which is different from the inlet pressure acting on said piston, said piston having a protuberance, seal means surrounding said piston for providing a seal with said bore and adapted to be engaged by said protuberance as said piston moves toward said outlet, a flat wave spring effective to operate between another portion of said piston and said seal means to urge said seal means into engagement with the protuberance of said piston, said proportioning piston having a lesser effective area exposed to fluid at said outlet than an effective area exposed to fluid received from said inlet when said seal means is in engagement with said piston whereby said piston will generate a higher pressure at said outlet than the pressure of the fluid received from said inlet, and means restricting the return flow of fluid to said inlet from said proportioning piston upon relief of the inlet pressure.

Claim 4

In a vehicle hydraulic brake system having a master cylinder and plurality of brake cylinders, a pressure regulating device adapted to be interposed between the master cylinder and at least one brake cylinder, said device including a housing having an inlet, an outlet, and a bore providing communication between said inlet and outlet, a pressure proportioning piston positioned in said bore and movable toward said outlet to generate a pressure at said outlet which is different from the inlet pressure acting on said piston, said piston having a protuberance, seal means surrounding said piston for providing a seal with said bore and adapted to be engaged by said protuberance as said piston moves toward said outlet, a flat wave spring effective to operate between another portion of said piston and said seal means to urge said seal means into engagement with the protuberance of said piston, said proportioning piston having a lesser effective area exposed to fluid at said outlet than an effective area exposed to fluid received from said inlet when said seal means is in engagement with said piston whereby said piston will generate a higher pressure at said outlet than the pressure of the fluid received from said inlet, and means restricting the return flow of fluid to said inlet from said proportioning piston upon relief of the inlet pressure.