Matrix table

Construction of a machine table for CNC-machining centres.

Construction

A matrix table comprises a support plate from plastic or phenolic resin- impregnated plywood. Grooves are milled into this support plate at regular intervals. Closable bores are located at somewhat greater distances in the plate. These are connected with the vacuum system.

The matrix table can be combined with positioning aids such as crosshair lasers or contour lasers.

Some manufacturers (e.g. SCM) offer aluminium matrix tables, whereby T-grooves are located at various points. Using these it is also possible to secure workpieces without a vacuum.

Function

If a panel-type workpiece of an arbitrary form is to be clamped then a slightly smaller shape is placed in the grooves of the matrix table with a foam rubber belt. The ends of the rubber belt must meet such that the enclosed surface of the matrix table is sealed. At least one of the bores must be open within the sealed area. If a workpiece is now laid in place and the vacuum activated, the workpiece will be held fast.

Some manufacturers also offer suction cups for use on matrix tables. These have a foot, which precisely fits into the table matrix. When the vacuum is activated the suction cup sucks the workpiece.

Advantages

  • Full-surface and highly precise workpiece support
  • The rubber belt enables very accurate alignment, also with complicated contours
  • Full-surface suction of larger panels possible - particularly important for nesting applications

Disadvantages

  • Formatting of workpieces without damaging the table surface is only possible with additional templates or suction cups
  • Setting up the table is comparatively laborious.

Images

Blocksauger auf Rastertisch
BIESSE
Rastertisch aus Phenolharz- Schichtholz
WEEKE
Aluminium-Rastertisch
SCM
Blocksauger für Rastertisch
SCM, 2004