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:
May. 03, 1994
Filed:
Jul. 28, 1992
Stanton D Saucier, Tarzana, CA (US);
Ricon Corporation, Pacoima, CA (US);
Abstract
A hydraulic drive passenger lift with distinct lifting 'up and down' (loading, unloading) and 'fold-unfold' (storage) motion patterns, includes a flow control structure that accommodates various hydraulic flows, somewhat unrestricted for 'up-and-down' movement, and different for 'fold' and 'unfold' movements. The flow control structure includes multiple paths between a source and an actuator, with control for selecting the appropriate path to yield predetermined flow rates. A solenoid driven spool valve and a biased movable orifice member select the desired path. Accordingly, while the flow is substantially unrestricted during 'up-and-down' movement, it is somewhat restricted for reduced speed during the 'unfold' movement and is more restricted during the power-driven 'fold' movement.