Tool locking apparatus for machine hammers

Abstract

In the front head (11) of a machine hammer (10), transversely disposed wedges (18) are adapted to lock the working tool (12) so that the working tool (12) is axially movable by form-restricted cooperation with recesses (16) on the working tool (12). Each wedge (18) is locked in the front head (11) by a key (20), which extends across the wedge (18) into engagement with a transverse bore (21) therein. The key (20) has a releasable locking device including a locking element affixed in the front head (11) and formed by a polyurethane block (24). The block (24) is provided with a through bore (27) and has elastically form-recovering material properties. When, for purposes of locking the key (20), the key (20) is pressed through the bore of the block (24), the block (24) is caused to expand resiliently into an annular groove (22) on the key (20), thereby locking the key (20) in the front head (11) and providing its wedge (18) locking function. In use of two wedges (18), one single key (20) is set to lock both wedges (18) and is locked by one single block (24).

Dependencies are inferred from the claim text.