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:
Oct. 22, 1985
Filed:
Mar. 30, 1983
Raymond W Born, Fountain Valley, CA (US);
Other;
Abstract
The invention comprises two embodiments of a hydraulically powered rotor and screw elevator equipped with a fail-safe control system. In each embodiment a dual lead steep-pitched screw is embraced by a rotor supporting the cab. In one embodiment the rotor is driven and in the other the screw is driven. In each embodiment the driven component auto-rotates during downward cab travel and is hydraulically driven during upward cab travel by a motor-pump unit. This unit functions as a motor during upward cab travel and as a pump during downward cab travel to provide pressurized fluid to various system components including the hydraulic speed control components. Pressurized fluid is supplied in varying volumes by a plurality of pumps connected in parallel. Both the rotor and the screw are equipped with fail-safe brakes. The driven component in each embodiment includes a normally closed brake releasable by a fail-safe control system including switches, relays and valves cooperating to safeguard against non-functional components and all hazards. The screw may be a tube supported from the upper end of a coaxial tube embracing both the tubular screw and its rotor, the supporting tube being slotted to accommodate brackets between the rotor and the cab or other load.