Tool holder for a rotary hammer

摘要

A tool holder ( 1 ) for a rotary hammer which has a tube like tool holder main body ( 10 ) having a side wall formed with through holes ( 11 ) for receiving corresponding locking bodies ( 12 ) and formed with additional through holes ( 40 ). The tool holder includes hardened metal driving ribs ( 46 ) each located on an insert ( 42 ) and the inserts are fitted within the additional through holes ( 40 ) so that the ribs extends axially and radially inwardly of the radially inward facing surface of the holder body. The locking bodies ( 12 ) are arranged to releaseably engage a corresponding axial closed groove of a tool or bit inserted within the tool holder and the ribs ( 46 ) are arranged to releaseably engaging a corresponding axial rearwardly open driving grooves of a tool or bit inserted within the tool holder. To simplify the process for forming the tool holder body ( 10 ) each additional through hole ( 40 ) is formed by at least two overlapping axially offset circular cross-sectioned through holes ( 40 a , 40 b) and the corresponding insert has a base ( 44 ) shaped to fit the through hole ( 40 ).