| 摘要 |
A fluid pressure chuck 20 comprises two sets of jaw members 31,32 to chuck a workpiece from two orthogonal directions, each set of jaw members 31,32 being associated with one of two coaxial cylinder assemblies including a rod 43,44 and a piston 41,42 in which the rod 43 from the first cylinder assembly is slidable within the rod 44 in the second cylinder assembly. Cam means associated with each set of jaw members 31,32 converts reciprocal movement of each cylinder assembly into opening and closing of the jaw members 31,32. The cam means (best viewed in figure 3) comprises an inclined groove 35 in each jaw member 31,32, each of the grooves 35 receiving a corresponding cam member 46,47 located on both of the rods 43,44 on the two cylinder assemblies. A notch 49 is also provided in either side of the rod 44 on the second cylinder assembly, so that the cam members 46 on the rod 43 of the first cylinder assembly is movable within the notch 49. Since cylinder assemblies for both sets of jaw members 31,32 are located inside the chuck 20, one or both of these sets of jaw members 31,32 can be actuated at any one time. Preferably the pistons 41,42 in the two cylinder assemblies have different pressure receiving areas 51a/b,53a/b, so that the two sets of jaw members 31,32 have different chucking forces. This arrangement allows for the tips of each rod 43,44 to be aligned within the chuck mechanism, which therefore allows the manufacture of smaller fluid pressure chucks. |
