Modular fixturing apparatus

Claim 1

A fixturing apparatus for positioning and holding a workpiece during a metal working operation comprising: (a) a mounting plate for holding said workpiece in a known, repeatable position and orientation, said plate having a workpiece receiving face, a first plurality of threaded holes in said face in a pattern specific to said workpiece for defining the location and orientation of said workpiece on said plate and adapted to locate and hold workpiece support and clamp devices, wherein said first plurality of threaded holes includes holes having a counterbored, reamed, unthreaded upper portion and a lower threaded portion adjacent thereto, and wherein said plate has a second plurality of clearance, plate mounting holes; and (b) a carrier apparatus for releasably and rigidly supporting said plate in an accurate, repeatable position thereon, said carrier apparatus comprising: (1) a unitary molded filled epoxy resin system structure wherein the filler comprises crushed granite rock having a mixture comprising particle sizes in the range of from 0.08 mm to 16 mm in the major diameter and constitutes from 50% to 99% by weight of said filled epoxy resin system; (2) at least one planar surface defined by adjacent perimeter faces substantially normal to each other end adapted to receive and hold said plate; (3) a base having a base surface substantially normal to said planar surface; (4) a plurality of non-movable plate locating stop means positioned at two adjacent perimeter faces of said planar surface and extending beyond said planar surface for engaging said plate; (5) pusher means positioned at perimeter faces of said planar surface opposing said stop means and extending beyond said planar surface for engaging and applying a force on said plate to urge said plate against said stop means; and (6) a plurality of threaded holes in said planar surface corresponding to said second plurality of clearance plate mounting holes.