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:
Mar. 16, 1976
Filed:
Dec. 20, 1974
Robert A Fritsch, Cedar Rapids, IA (US);
Harnischfeger Corporation, W. Milwaukee, WI (US);
Abstract
A mobile crane has a multisection telescopic boom comprising a fly section and an adjacent boom section into which it telescopes. Releasable locking means are provided on the boom fly section and the adjacent boom section to prevent the extended boom sections from accidentally telescoping under the weight of a load in the event of a hydraulic system failure. The locking means take the form of a jam plate located near the base end of the extended boom fly section and engageable in interfering relationship with a selectively movable spring biased locking member of a locking assembly mounted near the forward end of the adjacent intermediate boom section.