Patent ID: 6343797
Filing Date: 2002-02-05
Classification: B23B,Y10T

Abstract:
A chuck comprising:chuck jaws 2 guided in a chuck body 1; inner jaws 4, 38 connected to said chuck jaws 2, wherein the inner jaws 4, 38 can be engaged and disengaged with said chuck jaws 2 directly or indirectly via a rack gear 3, and are connected through a wedge-type mechanism to a central drawing head 12 which, in turn, is connected to a piston of a hydraulic cylinder 28 assembled on the rearward side of a main spindle 25 via a rod or pipe 13 guided through a central hole of said main spindle 25; wherein said inner jaws 4, 38 comprise connector means 4â€², 55 guided axially and radially, and provided with a rack gear 3 and a double locking device; said inner jaws 4, 38 are built together with counterweights 6 for compensation of the centrifugal force, wherein the inner jaws 4, 38 and said counterweights are formed as a single integrated unit; said inner jaws 4, 38 comprise two heads located on opposite sides of the chuck structure axis, the narrower one of which is in the form of a connector means 4â€² either provided directly with a rack gear 3 or embedding a connector means 55 provided with a rack gear 3 and guided axially, whereas the wider one of said heads, which forms a counterweight on the opposite side, comprises a hole 10, the axis of which defines an acute angle with respect to the chuck structure axis; respective heads of said inner jaws 4, 38 have equal dimensions between each other, wherein bridges 7, 8, 9 between the respective heads are translated axially relatively to each other; said wedge-type mechanism connected to said central drawing head 12 is arranged in such a way the central drawing head 12 comprises three cylindrical studs 11 fixed therein, tie axis of which define an acute angle with respect to the chuck structure axis; said studs 11 are connected into holes 10 bored into said counterweights 6; bushings 14 are built into holes formed in the chuck body 1 against respective chuck jaws 2, wherein the axis of said holes are parallel to the chuck structure axis; and a stud segment 15 with an axis in parallel to the chuck structure axis is guided in said bushings 14, wherein said stud segment 15 and the respective cylindrical stud 11 constitute a single integrated unit, or said stud segment 15 is built together with the cylindrical stud 11.