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:
Sep. 17, 1991
Filed:
Sep. 22, 1989
Kurt M Lloyd, Pewaukee, WI (US);
Harnischfeger Engineers, Inc., Brookfield, WI (US);
Abstract
A mast structure for a storage and retrieval machine is disclosed which includes first and second vertical members having lengths affixed to each other. The second vertical member includes a plate extending along the length of the second vertical member and spaced from the first vertical member in the direction of the path of travel of a base of the storage and retrieval machine. The first and second vertical members respectively have cross-section areas perpendicular to their lengths which are substantially equal to each other. The first and second vertical members together have a physical center and a centroidal axis both extending along the length of the members which may be adjacent to each other and preferably coincide with each other so that the two members together have a maximum section modulus in the direction of the path of movement of the base. The first vertical member has a tubular cross-section shape for guiding a carriage of the storage and retrieval machine along the length of the mast structure which is of a rectangular shape. The second vertical member is tapered so that the cross-section area of the second vertical member decreases in an upward direction to decrease the section modulus of the mast structure at its upper end where impact loading is less.