A tool cutter head

Claim 1

A tool cutter head (9) adapted to be releasably mounted on a tool holder (1) and comprising a body portion (10); cutting insert mouting means (11) located at a first end of the body portion (10); characterized in that a substantially U-shaped bushing (23) is articulatedly mounted in a recess (14) formed in a second end of the body portion (10) and defining a receiver socket adapted to receive an engaging head (5) of a drawbar (2) longitudinally displaced within the tool holder (1); juxtaposed surfaces of said recess and said bushing (23) constituting a first pair of coacting cam surfaces; constituent limbs (24a, 24b) of said bushing (23) being capable of limited displacement towards and away from each other along paths determined by said coacting cam surfaces; limb terminal portions (29a, 29b) projecting out of said second end and defining at their extremities a socket entry slot (33) having transverse dimensions less than those of the socket and greater than those of a neck portion (4) of said drawbar (2) adjacent said engaging head (5); transverse abutment surfaces (13) formed on said second end of said body portion (10) on either side of said limb terminal portions (29a, 29b) and adapted to be juxtaposed with respect to corresponding transverse abutment surfaces (7a, 7b) formed on said tool holder (1); outer surfaces of said limb terminal portions constituting respective, longitudinally directed, abutment surfaces (30a, 30b) adapted to be juxtaposed with respect to corresponding longitudinally directed, abutment surfaces formed on said tool holder (1); inner surfaces (31a, 31b) of said terminal portions (29a, 29b) being adapted to be juxtaposed with respect to corresponding surfaces on said engaging head (5) and adapted to constitute a second pair of coacting cam surfaces; the arrangement being such that with said engaging head (5) of said drawbar (2) located in said receiver socket, a traction force exerted on said drawbar (2) results in the transverse abutting surfaces (30a, 30b) of said limb terminal portions (29a, 29b) being displaced into a clamping abutment with the corresponding transverse abutment surfaces formed on said tool holder.