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:
Apr. 05, 1994
Filed:
May. 03, 1991
Robert M Stone, Alta Loma, CA (US);
Other;
Abstract
A self-adjusting load elevator has a base, a horizontal load platform, a vertically expandable scissors linkage coupled between the load platform and the base, and an air actuator chamber. The air actuator chamber is formed of a compressible bellows and a fixed volume reservoir. The bellows is compressible between specified maximum and minimum bellows heights which correspondingly determine substantially different maximum and minimum bellows volumes and coupled between the scissors linkage and the load platform. The air reservoir is coupled to the bellows and has a fixed volume that is substantial compared to the difference between the maximum and minimum bellows volumes. A normally closed air inlet/outlet valve is coupled to the air actuator.