Seam Detector

Hall-Sensor for fabric dyeing machines

The Seam detector uses the HallEffect, which means the sensitivity is not affected by machine speed or the stainless wall of the machine. It can be easily installed on the outside of the machine.

The Seam detector is designed for use on most types of fabric dyeing machines. A sensor unit is mounted on the outside of the machine at a point near to where the fabric passes. A magnet is sewn into the fabric seam and this triggers the sensor when it passes. A relay is activated in a separate amplifier unit for about 2 seconds, and the volt free changeover contact on this relay may be used as required.

Typical uses include stopping the machine when the seam is found for unloading, or checking that the fabric is circulating within a particular time frame.

Sensitivity adjustment

The sensitivity of the unit can be adjusted, using a potentiometer. At maximum sensitivity the passing of the supplied magnet, when correctly orientated, will be detected at a distance of at least 250mm.

Use of dual sensors:

Only in case of very wide tubes: If the fabric can move more than 150mm from side to side it may be advisable to use two sensors per rope.

The detector should be mounted on a stainless bracket. This allows enough cooling to keep the unit well within operating temperature, even at machine temperatures higher than 125°.

Sensor and amplifier