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:
Aug. 18, 1981
Filed:
Dec. 03, 1979
James G Morrow, Sr, Manitowoc, WI (US);
The Manitowoc Company, Inc., Manitowoc, WI (US);
Abstract
Separate torque converters are selectively clutched to the hoist and drag drums of a dragline machine with a selectively engageable clutch providing a power interlock of the output of both torque converters to either one of the drums as desired. The application and control of torque from the two torque converters to the hoist drum is in parallel and to the drag drum is in series progressive, i.e., the drag converter being engaged first and going from zero to maximum while the hoist converter goes from zero to about fifty percent of capacity as the drag converter reaches maximum. The reserve torque in the hoist converter may be selectively applied to the hoist drum to step the drag bucket up if the drag drum approaches a stall condition. The hoist converter may also be selectively engaged to apply a predetermined hold back force during bucket lowering. Another clutch may be engaged to interlock the two drums together for joint operation by the hoist converter. Thus, dragline holdback during hoisting may be achieved by the drag drum brakes, the drag drum converter or the drum interlock thereby providing the operator with considerable flexibility in controlling the path of the drag bucket during hoisting.