| 摘要 |
<p>Pieces of linen moving along a conveyor are folded in a rolling sequence, edge to edge, accurately, with the help of a clamping arrangement. The differences of the distances covered by the piece of linen, for different speeds of motion during the clamping operation, and if necessary, during the releasing operation, are compensated by the regulating of the distance of an edge detector in front of the clamping arrangement. The detector is positioned at a distance corresp. to the maximal forward speed. The distance covered by the piece of linen during the clasping operation and if necessary during the release of the piece of the linen also, is determined by measurement. The releasing operation is only effected when the back edge of the piece of linen has moved away from the detector over a distance which is equal to the difference between the distance envisaged for the maximal forward speed, and the distance determined by measurement. Only the distance covered during the clamping operation is measured and multiplied, before the difference is determined, by a fractor >=1. Usd to ensure that the piece of linen is released correctly without it being necessary to alter the position of the edge detector relatively to the clamping device, so that the front and rear edges are laid accurately one upon the other.</p> |
