| 摘要 |
898,571. Work-holders. LARRAD (HYDRAJAWS) Ltd. Sept. 21, 1959 [May 19, 1959], No. 16908/59. Class 83 (3). In a work-holder, the work is gripped by plungers operated through a closed hydraulic circuit when a piston or pistons is/are actuated by screw means. A mandrel comprises a body 1, Figs. 1, 3, having plungers 3 radially movable in bores 2, pressure being applied to these bores by preferably a number of pistons 15 which are axially moved in the body by a washer 19 on screwing a nut 21 on a stud 20. The pistons 15 compress fluid in the circuit 16, 17, 10, 9, and move plungers 3 to hold work 23, axial movement of the plungers being limited by plates 6. The plungers are retracted by springs 27 when nut 21 is released. Initial location of the work is by washers 24 screwed to body 1, the washers being subsequently removed if the work is to be machined internally. In a modification, piston 15 are replaced by one piston coaxial with the body, and the washers 24 actuate dished washers for initially locating the work. In a further modification, the work 73, Fig. 5, is held in a chuck 61 by plungers 65, and is initially centred by plates 74 secured to chuck 61. Plungers 65 are controlled through an hydraulic circuit 76, 69, 70, operated by pistons 75 axially movable by a screwed ring 71. The chuck 61 may be mounted on a face plate 79 for internal machining of the work. |
