Dashpot apparatus including a flexible diaphragm piston

Claim 1

A dashpot assembly, comprising housing means including first and second housing sections, moveable wall means situated within and cooperating with said housing means to define at least first and second distinct and variable chamber means at either side of said moveable wall means and internally of said housing means, said moveable wall means comprising a relatively flexible diaphragm peripherally retained generally between and by said first and second housing sections and having a relatively rigid diaphragm-engaging body, said diaphragm being generally juxtaposed to said diaphragm-engaging body so as to be situated on generally the first chamber side of the diaphragm-engaging body, said diaphragm-engaging body being situated as to be on generally the said second chamber side of said diaphragm, said diaphragm comprising a generally relatively thick diaphragm body portion positioned in juxtaposed relationship to said diaphragm-engaging body, said diaphragm body portion comprising recess-like means formed generally on said second chamber side thereof, said diaphragm-engaging body comprising a flange means, said flange means being received in said recess-like means for operatively connecting said diaphragm to said diaphragm-engaging body, motion transmitting means operatively carried by said moveable wall means and being effective when actuated to move said moveable wall means in a direction toward said first chamber, said motion transmitting means being operatively connected to said diaphragm-engaging body, conduit means carried by said moveable wall means for completing communication between said first and second chambers, said conduit means including sintered gas permeable metering means having the capability of permitting a preselected volume rate of flow of air therethrough at a corresponding air pressure differential thereacross, said conduit means comprising first passage means formed in said diaphragm-engaging body and containing said gas permeable metering means and second passage means formed through said diaphragm body portion and communicating with said first passage means, said second passage means comprising a first conduit section and a second conduit section each formed through said diaphragm and spaced from each other, said diaphragm-engaging body having annular passage means formed in the face thereof juxtaposed to said diaphragm in a manner to inter-connect said first passage means with said second passage means, and third passage means formed through said diaphragm-engaging body, said third passage means being effectively closed to flow therethrough by said diaphragm when said diaphragm and said diaphragm-engaging body are being moved in said direction toward said first chamber, said diaphragm being operative to open said third passage means to flow therethrough from said second chamber to said first chamber when said diaphragm and said diaphragm-engaging body are being moved in a second direction opposite to said first direction and toward said second chamber.