Clamping and drilling device for a curved plate

A clamping and drilling device for a curved plate that has a radius of curvature and a width, said device comprising:

• a machine body;
• an indexing apparatus mounted on said machine body, said indexing apparatus having an index plate mounted rotatably thereon;
• a clamping assembly including an upright post that has a lower end fixed to said index plate, a pivot seat fixed on said upright post between said index plate and a top end of said upright post, a first engaging unit and upper and lower circular hollow casings mounted coaxially to said upright post, each of said hollow casings having a covering plate spaced from the other one of said covering plates, said lower circular hollow casing being attached securely to said index plate, said upper circular hollow casing having a second engaging unit, a threaded hole which extends vertically through said second engaging unit, and a threaded shaft which is threaded into said threaded hole, said threaded shaft having a lower end journalled to said pivot seat parallel to said upright post, thereby retaining said upper hollow casing on said upright post at a desired height relative to said lower casing which is equal to said width of said curved plate, said second engaging unit engaging said first engaging unit so as to prevent said upper hollow casing from rotating relative to said upright post and so as to permit said upper hollow casing to move axially along said upright post;
• each of said upper and lower casings having an abutting plate which is fixed perpendicularly on a respective one of said covering plates and which extends radially thereon, a radial groove and an elongated movable piece provided slidably in a respective said radial groove, each of said elongated movable pieces having two clamping units, each of said upper and lower casings further having a driving means for moving said two clamping units relative to one another;
• a control member for actuating said driving means synchronously;
• means for synchronously moving said elongated movable pieces along said radial grooves of said lower and upper casings so as to define a distance between said elongated movable pieces and said upright post, said distance being equal to said radius of curvature of said curved plate;
• and
• a drilling assembly provided on said machine body, said drilling assembly including an upright holding member with a first drilling bit extending toward an axis of said upright post, a second drilling bit which is disposed right below said first drilling bit in a parallel manner and which extends toward said axis of said upright post, and means for adjusting a vertical height between said first and second drilling bits.