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US 4,852,661 AGranted
Portable concrete hammer
OwnerDavid A. Ellingtoninventor
Life of this patent
Estimating the term…
Abstract
A portable concrete hammer including a wheeled carriage, a mast movable between a vertical operating position and a horizontal transport position, and an automatic ratchet drive that advances the concrete hammer over a concrete surface during the portion of the operating cycle when the weight is being raised.
Claims14
A self propelled portable concrete hammer, comprising:
- a frame supported by ground wheels;
- a mast attached to said frame:
- A weight adapted to slideably engage said mast;
- means for selectively lifting said weight to a predetermined elevation and allowing said weight to drop by gravity to impact a concrete surface;
- and
- a drive attached to and interconnecting said selective lifting means and one of said ground wheels, said drive being operable to advance said concrete hammer over the concrete surface while said weight is being raised ;
- wherein, the drive will automatically engage one of said ground wheels as the weight is being raised and will automatically disengage from said one of said ground wheels as the weight falls;
- and, wherein the incremental distance traveled by the concrete hammer is operatively associated with the raising of the weight relative to the mast.
5 more elements
Dependencies are inferred from the claim text.