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. 15, 1977
Filed:
Aug. 27, 1975
Roger D Mickelson, Cedar Rapids, IA (US);
FMC Corporation, San Jose, CA (US);
Abstract
There is disclosed a telescoping boom with first and second motors, each connected between adjacent boom sections to extend and retract one boom section with respect to the other. Each motor has a piston slidably received in a cylinder to define an extend chamber on one side of the piston and a retract chamber on the other side thereof. Each piston has a rod extending from the cylinder which has two passages therein, one communicating with the extend chamber and the other communicating with the retract chamber. A control valve has a first portion for control of the first motor and a second portion for control of the second motor. The hydraulic passage between the retract chamber of the second motor and the second valve portion includes the retract chamber of the first motor. The hydraulic passage between the extend chamber of the second motor and the second valve portion, and only that passage, passes over a reel between said members.