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:
Nov. 04, 2003
Filed:
Mar. 07, 2002
Daniel Brian Zakula, Sr., Mokena, IL (US);
Daniel J. Olson, Orland Park, IL (US);
Mi-Jack Products, Inc., Hazel Crest, IL (US);
Abstract
A hydraulic system for actuating opposed arms of a grappler for a gantry crane dampens swaying motion of the arms. Within a conduit which carries pressurized fluid to and/or from actuators to pivot the arms, a dampener includes a restrictor having an orifice to restrict the flow in at least one direction. Each of the dampeners can include a respective check valve to permit free flow through one direction of the conduit and to direct reverse flow through the orifice. In a specific embodiment, a load is received between opposed arms of the grappler to seat upon shoes which extend inwardly from the arms. To urge the shoes to remain in secure lifting contact under the load, flow is restricted when the swaying load moves the arm outwardly, permit free motion of the arm when the swaying motion pulls the arm inwardly.