Patent ID: 9381696
Filing Date: 2016-07-05
CPC Classification: B29C,B29D,B29L

Claim Text:
1. Stretching unit comprising a sliding chain transport system, having the following features: two peripheral guide paths, provided at a distance from one another with respect to a vertical longitudinal plane, are provided, a transport chain is peripherally arranged on each of these guide paths, each of the two transport chains comprises a plurality of chain links articulated to one another, clip chain units are provided, which are subdivided into a clip part and a chain part which comprises chain links, the clip part comprises at least one clip mounting for fixing an edge of the material web to be stretched, via which the material web can be gripped and conveyed from an entrance zone via a stretching zone to an exit zone whilst releasing the material web, the guide path comprises a guide rail in each case, the clip chain units comprise at least one stretching force running face, oriented on the stretching side, and a chain force running face facing counter thereto, which are oriented parallel and facing one another, via which the clip chain unit is displaceably guided along the guide rail comprising a chain force running face and a stretching force running face oriented parallel and counter thereto, the chain force running face, in the region of the chain force running face height thereof, and the stretching force running face, by way of the stretching force running face height thereof, interacting with and being guided by the guide rail, a support rail is further provided, which absorbs the gravitational force of the clip chain unit and comprises a support rail running face, the clip mounting, provided on the clip part, for fixing the edge of the material web to be stretched is arranged in such a way that the stretching forces introduced to the clip body via the material web to be stretched act in a stretching plane which is oriented perpendicularly to the gravitational force of the clip chain unit, on different portions of the guide path, centrifugal forces, lateral guidance forces and transverse forces also further act on the clip chain unit, the centrifugal forces acting on the centre of gravity of the chain clip unit act in a centrifugal force plane which is parallel to or coincident with the stretching plane, the transverse forces or the lateral guidance forces act in a transverse force or lateral guidance plane parallel to the stretching force plane, the clip chain unit is formed in such a way that the centrifugal force plane and the lateral guidance or transverse force plane and the stretching force plane are positioned above the lower edge of the guide rail or above the lower end of the chain force running face and/or the stretching force running face, the centrifugal force plane and the lateral guidance or transverse force plane and the stretching force plane intersect the guide rail and the chain force running face in the region of the chain force running face height thereof and the stretching force running face in the region of the stretching force running face height thereof, and one or more sliding elements comprising a bracing face arrangement for bracing the clip chain unit with respect to the running face of the support rail are provided on the underside of the clip chain unit, the plane of gravity which extends through the centre of gravity of the clip chain unit intersecting the bracing face arrangement, with respect to the maximum extension width thereof, transversely to the feed direction and intersecting the support rail running face.