Patent ID: 6173738
Filing Date: 2001-01-16
Classification: B60G,F16K,Y10T

Abstract:
A pressure maintenance valve for pneumatic apparatus including air spring systems, comprising: a valve housing having inlet and outlet passages, a valve member disposed in said housing and including a membrane supported in said housing and having at one side thereof an annular valve structure disposed opposite an annular valve seat so as to divide the space adjacent said membrane into inner and outer concentric chambers separated by said valve seat when said membrane is forced into engagement with said valve seat, a valve spring engaging said membrane for biasing said membrane into engagement with said valve seat, one of said concentric chambers being in communication with said inlet passage and the other with said outlet passage, said spring being selected to have a spring force sufficient for closing said valve when the pressure in said inlet and outlet passages falls below a predetermined value so as to close said valve for maintaining a desired minimum pressure in said outlet and in a pneumatic apparatus connected thereto, and said membrane having normally the shape which it assumes when said valve is held open by the pressure in said inlet and outlet passages to provide communication between said inlet and outlet passage, said membrane having a central opening and one of said inlet and outlet passages extending through said central opening providing for communication with said inner concentric chamber.