Spoilboard gasket tile system for increased work-hold vacuum pressure
View Patent ↗In one embodiment, a spoilboard gasket tile system for increased work-hold vacuum pressure is provided. In particular, a universal work-hold gasketing solution is defined for vacuum table machining processes that can be used in a variety of sizes and applications, where the surface of a porous spoilboard (e.g., MDF/LDF or a porous plastic) is covered by a non-porous gasketing sheet (e.g., an adhesive foam layer) that is configured with a plurality of spaced apertures (holes) sized and located to create a corresponding plurality of focused vacuum passageways to suction clamp any workpiece placed thereon. In one particular embodiment, the spoilboard with gasketing are prepared as an interchangeable tile unit, allowing for dynamic configuration and reconfiguration of an array of spoilboard gasket tiles to cover a vacuum table, as well as for replacement of specific tiles as needed based on localized wear of the tiles.
1 . A vacuum-pressure-improving, spoilboard tile for CNC machine vacuum tables, the spoilboard tile comprising:
a porous spoilboard substrate that is planar and that has a spoilboard thickness, the porous spoilboard substrate having a top spoilboard surface and a bottom spoilboard surface;
a first non-porous gasket layer that is substantially planar and that has a first thickness that is less than the spoilboard thickness, the first non-porous gasket layer having a first top surface and a first bottom surface;
a first adhesive layer positioned between the first bottom surface of the first non-porous gasket layer and the top spoilboard surface of the porous spoilboard substrate, the first adhesive layer adhering the first non-porous gasket layer to the porous spoilboard substrate on the top spoilboard surface;
a second non-porous gasket layer that is substantially planar and that has a second thickness that is less than the spoilboard thickness, the second non-porous gasket layer having a second top surface and a second bottom surface; and
a second adhesive layer positioned between the second top surface of the second non-porous gasket layer and the bottom spoilboard surface of the porous spoilboard substrate, the second adhesive layer adhering the second non-porous gasket layer to the porous spoilboard substrate on the bottom spoilboard surface;
wherein the first non-porous gasket layer comprises a plurality of apertures arranged in a distributed pattern, and where in the second first non-porous gasket layer comprises a plurality of apertures arranged in the distributed pattern, further wherein the porous spoilboard substrate comprises a plurality of through-holes extending from the top spoilboard surface to the bottom spoilboard surface, the plurality of through-holes of the porous spoilboard substrate being arranged in the distributed pattern and substantially aligned with the plurality of apertures of the first non-porous gasket layer and the plurality of apertures of the second non-porous gasket layer, such that the corresponding apertures of the first non-porous gasket layer, corresponding though-holes of porous spoilboard substrate, and corresponding apertures of the second non-porous gasket layer are positioned in same locations across the spoilboard tile, define a common diameter and are axially aligned to provide continuous airflow paths through the spoilboard tile;
wherein the spoilboard tile is individually replaceable when assembled among an array of replaceable spoil board tiles on the CNC machine vacuum table.
2 . The spoilboard tile of claim 1 , wherein the distributed pattern for the plurality of apertures is an offset grid pattern configured to balance vacuum distribution across the first top surface of the first non-porous gasket layer or the second top surface of the second non-porous gasket layer.
3 . The spoilboard tile of claim 1 , wherein the first non-porous gasket layer and the second non-porous gasket layer comprise a medium-density closed-cell polyvinyl chloride foam material.
4 . The spoilboard tile of claim 1 , wherein the porous spoilboard substrate comprises a medium-density fiberboard material.
5 . The spoilboard tile of claim 1 , wherein the first non-porous gasket layer and the second non-porous gasket layer further comprise seam-gasketing material positioned along one or more peripheral edges of the porous spoilboard substrate and configured to impede vacuum leakage at joints between adjacent spoilboard tiles when assembled in the array.
6 . The spoilboard tile of claim 1 , wherein the porous spoilboard substrate comprises interlocking edges along at least two sides configured to engage with complementary interlocking edges of adjacent spoilboard substrates of the array of replaceable spoilboard tiles, and wherein the seam-gasketing material is positioned at interfaces between the interlocking edges.
7 . The spoilboard tile of claim 6 , wherein the interlocking edges comprise tongue-and-groove joints configured to prevent air leakage between adjacent gasket layers.
8 . The spoilboard tile of claim 1 , wherein the top spoilboard surface and first non-porous gasket layer are interchangeable with the bottom spoilboard surface and second non-porous gasket layer such that the spoilboard tile is reversible to extend usable service life.
9 . The spoilboard tile of claim 1 , wherein the spoilboard tile is a square.
10 . The spoilboard tile of claim 1 , wherein the second non-porous gasket layer further comprises a plurality of hold apertures configured to locally increase vacuum holding force at selected locations of the spoilboard tile.