US 4,227,746 A · Braking pressure control unit for a dual circuit brake system

Abstract

The braking pressure control unit for a dual circuit brake system comprises a housing with two closure members arranged therein coaxially and in tandem. In their rest position, the closure members are held spaced apart from associated valve seats by a control force. The control force acts directly on a first of the two closure members which in turn bears against a second of the two closure members provided both are in the open positions. At least one closure member consists of a shaft element having one end in an operative relationship with the adjacent end of the other closure member and a closure element in a slidably sealed relationship with the outer surface of the shaft element, the closure element being displaced between limits of the shaft element. A weak closure spring biases the closure element toward its associated valve seat.

Claims17

Dependent claims

A braking pressure control unit for a dual-circuit brake system comprising:

a housing accommodating therein two coaxial valve chambers disposed in tandem with respect to each other;
a valve seat disposed in each of said valve chambers;
and
a closure member disposed in each of said valve chambers in an opening and closing relationship with an associated one of said valve seats, each of said closure members, in the rest position, being held in a spaced relationship with its associated one of said seats by a control force;
at least one of said closure members includes.
a first shaft element having one end in an operative relationship with an adjacent end of the other of said closure members,
a first closure element in a slidably sealed relationship with the outer surface of said first shaft element, said first closure element being displaceable between limits on said first shaft element, and
a first closure spring biasing said first closure element toward an associated one of said valve seats.

5 more elements

A braking pressure control unit for a dual-circuit braking system comprising:

a housing accommodating therein two coaxial valve chambers disposed in tandem with respect to each other;
a valve seat disposed in each of said valve chambers;
and
a closure member disposed in each of said valve chambers in an opening and closing relationship with an associated one of said valve seats, each of said closure members, in the rest position, being held in a spaced relationship with its associated one of said valve seats by a control force;
p1 a first of said closure members being a stepped piston having
a first portion of larger cross-section extending out of an associated one of said two valve chambers in a sealed relationship thereto toward said control force, and
a second portion of smaller cross-section extending out of said associated one of said two valve chambers in a sealed relationship thereto towards a second of said closure members.

4 more elements

Dependencies are inferred from the claim text.

Braking pressure control unit for a dual circuit brake system

Life of this patent

Braking pressure control unit for a dual circuit brake system

Life of this patent

Abstract

Claims17