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. 14, 1981
Filed:
Jul. 18, 1979
Harlan D Olson, Sandy, OR (US);
Cascade Corporation, Portland, OR (US);
Abstract
An extensible-contractible four-stage telescopic mast for a lift truck having a single fluid-actuated ram of low-collapsed height for high visibility which accomplishes both free lift and mast extension. The associated chain reeving of the mast provides a lesser ratio of load carriage speed to ram extension speed during free lift than during mast extension. To obtain substantially uniform speed of the load carriage throughout its lifting range, the ram assembly has a variable speed of extension substantially inversely proportional to such ratio such that ram speed is higher during free lift than during mast extension. An arrangement of the four mast sections, associated chain reeving and hydraulic conduits is provided which is especially conducive to high visibility and maximum load capacity.