The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 07, 1994
Filed:
Aug. 07, 1992
Bernard J Wallis, Dearborn, MI (US);
Other;
Abstract
A self contained gas spring comprising a cylindrical housing having a closed end, an open end and a cylindrical bore. A cylindrical sleeve extends into the bore of the housing. The sleeve has at least a portion thereof forming an internal cylindrical surface. A piston rod extends through an opening in the sleeve and has a piston contacting the cylindrical surface. A portion of the sleeve defines a first space between the sleeve and the bore of the housing. The first space communicates with a second space between the piston end of the piston rod and the closed end of the housing. A charging valve is provided in the closed end of said housing for charging the space at the piston end of said piston rod and the space between the sleeve and the housing with gas under pressure. A third axial space is provided between the cylindrical surface on the sleeve and the piston rod above the piston and is isolated from the first space and second space. When the gas escapes past seals into the third space a pressure limiting one-way valve comprising an annular groove, circumferentially spaced passages and an annular elastic seal which normally seals the groove relieves pressure in the third space when it exceeds the pressure in the first space, the annular seal is tensioned such that at least a portion thereof is flexed out of engagement with the diverging surfaces to vent the third space into the first space.