Patent ID: 6955027

Claim:
Crinkling device for a wrapping machine, designed to adjust the width of a foil web to be wrapped around an object between a full first web width (W 1 ) and a substantially narrow reduced second web width (W 2 ), said crinkling device comprising a frame connected to a foil dispenser comprised in the wrapping machine, said foil dispenser carrying a foil web roll of foil web having a longitudinal upper edge and a longitudinal lower edge, a first wheel rotatably mounted on the frame, a second wheel rotatably mounted on the frame at a distance from the first wheel, an endless drive element, which is passed over the first wheel and the second wheel, forming a first drive element portion and a second drive element portion, said portions extending adjacently and parallel to each other between the wheels in the widthwise direction of the foil web, a power means for moving the drive element optionally in a first running direction with the first drive element portion moving upwards and the second drive element portion moving downwards, and in an opposite second running direction with the first drive element portion moving downwards and the second drive element portion moving upwards. a first carriage, which is fastened to the first drive element portion and guided in the frame so as to be movable in the widthwise direction of the foil web, a first criniding element, which is mounted on the first carriage for crinkling the upper edge of the foil web, a second crinkling element, which is movable by the action of the drive element in the widtbwise direction of the foil web for crinkling the lower edge of the foil web, characterized in that the crinkling device comprises a slide rod, to which the second crinkling element is fastened and which is guided in the frame so as to be movable in a substantially vertical direction between a lower position, in which the second crinkling element is out of contact with the lower edge of the foil web, and an upper position, in which the second crinkling element deflects the lower edge of the foil web upwards so as to crinkle it, said slide rod being arranged to return towards the lower position when not exposed to a force acting in the upward direction; first coupling means for forming a releasable coupling between the slide rod and the first drive element portion when the drive element is running in the first direction to move the second crinkling element to the upper position; and second coupling means for forming a releasable coupling between the slide rod and the second drive element portion when the drive element is running in the second direction to move the second crinkling element to the upper position; so that, by driving the drive element in the first running direction, the foil web can only be crinkled from its lower edge, and by driving the drive element in the second running direction, the foil web can be crinkled optionally either from the upper edge without crinkling the lower edge or from the upper edge and the lower edge simultaneously.