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. 28, 1981
Filed:
Nov. 06, 1978
Theodore B Hogg, Aurora, IL (US);
Lawrance F Berg, Lockport, IL (US);
Caterpillar Tractor Co., Peoria, IL (US);
Abstract
A crane comprises a lower frame having an upper frame rotatably mounted thereon. A pair of rear roadwheels are rotatably mounted on either end of an axle housing pivotally mounted on the lower frame and suspended thereunder by a pair of laterally spaced suspension cylinders. A boom, pivotally mounted on the upper frame, is adapted to be lowered and positioned forwardly of the crane when it is driven to a remote job site. During such forward positioning of the boom, either when loaded or unloaded, a cam secured to the upper frame trips an air valve for opening a pair of slave valves to communicate hydraulic fluid between the head ends of the suspension cylinders to permit the axle to oscillate. When the crane is placed in operation and the upper frame is rotated on the lower frame, the cam will release the air valve which closes the slave valves to block communication of hydraulic fluid between the suspension cylinders whereby the axle is placed in a lock-out condition of operation. The rod ends of the suspension cylinders are preferably disposed in unattached relationship adjacent to the axle housing, but could be secured thereto.