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:
Dec. 14, 1993
Filed:
May. 04, 1992
Applicant:
Inventor:
Carl E Redman, Lake Oswego, OR (US);
Assignee:
Post Industries Incorporated, Portland, OR (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
E05F / ;
U.S. Cl.
CPC ...
49360 ;
Abstract
A door is supported for shifting between first and second positions, respectively opening and closing a doorway. A fluid actuator, such as a pneumatic cylinder, is used to shift the door between such positions. The fluid actuator reduces the velocity of the door as the door approaches at least one of the open and closed positions. In the case of a pneumatic cylinder, both sides of the cylinder may be subjected to relatively high air pressure when the door is stationary. To reduce the velocity of the door as it approaches the open or closed position, the rate of bleeding of air from one side of the cylinder is reduced.