Segmental pressure pad
Sanding pads divided into segments, whereas each segment can be applied with more or less pressure. Between the segments and the sanding belt a steel strip covered with felt and graphite is inserted at the sanding pad.
The pressure can be generated by pneumatic cylinders (most manufacturers) or electromagnets (e.g. company Heesemann). A perfect sanding result can be expected, especially if a perfectly adjusted sanding pressure is applied to each point of the workpiece surface. Therefore, the electronic sanding pad permanently requires accurate data of size and location of the workpiece in the machine.
The workpiece is scanned while entering the machine. This information is transferred to the machine control and then to the segments of the sanding pad.
The scanning is carried out mechanically by sensing rollers or without contact by optical sensors. Normally 2 rollers are applied for one segment of the pressure beam. So machines with variable edge control can maintain the pressure setting for the segments above the workpiece edges.
The technical solutions of the manufacturers differ in the way of scanning, the construction of the sanding pad aggregate and also the transfer of the pressure to the workpiece.
Names for segmental pressure pads of different manufacturers
Paul Ott GmbH
The Italian manufacturer SCM offers the segmental pressure pad in three levels of automation