Back to results
US 4,227,679 AGranted
Hoist with two or more hoisting units
AssigneeMannesmann Demag A.G. Wolfgang-Reuter-Platz
InventorsFred Wiggershaus, Felix Schafer
Life of this patent
Estimating the term…
Abstract
A multi-unit hoist apparatus is provided having an overload arrangement in the form of reversible pressure medium cylinders connected to the fixed end of each hoist unit in the apparatus. Appropriate controls are incorporated into the pressure medium supply to each unit, whereby if the load becomes unbalanced the unit subjected to an overload is relieved when the overload reaches a specific preset level.
Claims7
A multi-unit hoist apparatus comprising
- (a) a hoist body;
- (b) a plurality of hoist units disposed on said body;
- (c) a cable extending from each hoist unit to a point on said body;
- (d) a load support suspended from each cable of each unit;
- the improvement characterized by
- (e) a reversible pressure medium unit disposed in each cable adjacent said hoist body;
- (f) the end of each said cable opposite its respective hoist unit connected to the piston rod of its respective pressure medium unit;
- (g) a supply of pressure medium;
- (h) flow communication means between said supply and each said reversible pressure medium unit;
- and
- (i) an overload check valve in said flow communication means for each said pressure medium unit;
- (j) each said overload check valve preset to allow pressure medium flow between each individual unit to said source, if overloaded.
9 more elements
Dependencies are inferred from the claim text.