Power chuck with quick change top jaw

In a chuck construction having a housing rotatable about an axis, and a plurality of jaw carriers mounted on the housing for movement radially thereof, each jaw carrier being adapted to have a top jaw mounted thereon adjacent a front face of the housing, and releasable locking means associated with each jaw carrier for permitting secure mounting and quick changing of the top jaw relative to the respective jaw carrier, the improvement wherein said releasable locking means comprises:

• a bore formed in said jaw carrier in generally parallel relationship to said axis, said bore opening inwardly from a front face of the jaw carrier;
• a post fixed to and projecting rearwardly from a rear face of the top jaw for slidable insertion into said bore for permitting the rear face of the top jaw to be positioned directly adjacent the front face of the jaw carrier;
• releasable locking means cooperating between said jaw carrier and said post for permitting secure and rigid mounting but quick changing of the top jaw relative to the jaw carrier;
• and
• said locking means including opening means formed interiorly of said jaw carrier and extending in generally intersecting relationship with said bore, said opening means extending generally radially and including inner and outer portions which are disposed respectively on radially inner and radially outer sides of said bore, outer and inner clamp members slidably disposed respectively within the outer and inner portions of said opening means, threaded spindle means extending between and being threadedly connected to said inner and outer clamp members for causing movement of said inner and outer clamp members in opposite directions relative to one another in response to rotation of said spindle means, and rib-and-groove wedge means formed on and cooperating between said inner and outer clamp members and diametrically opposite sides of said post for creating a rigid but releasable clamping engagement on diametrically opposite sides of said post at locations which are disposed on radially opposite sides of said post relative to said axis for rigidly securing said post to the respective jaw carrier.