Insinooritoimisto Pesmel Oy

Jorma Surakka

Jari Maki-Rahkola

Juhani Kononen

Mauri J Kononen

A device assembly for wrapping a heat sealing plastic film around an article at a packing station comprises a cylindrical member having a length greater than the width of the plastic film and movable towards and away from the packing station. The cylindrical member comprises a curved external surface, a heater mounted on the curved external surface for heating the plastic film for heat bonding the plastic film to the surface of the article, a cutting device mounted in the cylindrical member for cutting the plastic film, and a retaining device provided on the external surface of the cylindrical member for retaining the trailing edge of the plastic film on the external surface.

Device assembly

The invention relates to a device assembly for wrapping a heat sealing plastic film (3) coiled from a store roll (2) in a packing machine around goods (5) at a packing station (4), the device assembly comprising means movable towards the packing station to carry out the following periodical actions on the plastic film (3) coiled from the store roll (2)

The problem involved in wrapping a stretched plastic film around a load by rotating the load and the plastic film feed roll is often that the film will not adapt well enough to the shape of the load, will not form an elastically tensioned package, and will not necessarily be by its stretch ratio and thickness sufficiently uniform and suitable for the product in question. In the present invention, a method has been developed for wrapping a stretched plastic film around the circumference of a load by rotating the load and the plastic film feed roll each about its axis in order to unwind the stretchable plastic film from the feed roll and to wrap the stretched plastic film around the circumference of the load and by braking the plastic film in order to stretch it between the braking point and the wrapping point. The advantages of the invention are based on the fact the braking power which induces the stretching of the plastic film is regulated on the basis of the circumferential speed of the load. In this manner it is possible to achieve completely simultaneous stretching and wrapping, wherein the contact point between the load and the plastic film constitutes the downstream end of the film-stretching distance.

Method and apparatus for wrapping a plastic film around a load

The invention relates to a transfer car for heavy loads, a car which has a chassis frame (1) moving on wheels (2) and having a raisable flatbed (3) on top of it, in which an axle (4'), mounted with bearings to the chassis frame and locked to one of the two wheel pairs, is coupled by power transmission means (5') to a transfer motor (6'), for transferring the car, and which additionally has a lever mechanism (7), connected to the flatbed (3), turning on transverse axles primarily in the forward and back ends and coupled to a raising motor (6') by a power transmission (5'), for raising and lowering the flatbed (3). In prior-art transfer cars it has not been possible to exploit the car-transfer mechanism in any way in the load-raising mechanism. Thus the transfer cars for loads such as paper rolls have so far been of a complicated structure and expensive. In the present invention, synergy has been produced between the raising and trasfer mechanisms by fitting the lever mechanism (7) to turn on the axis (4', 4') of the two wheel pairs (2), being freely rotatably mounted with bearings (8) at least on that axle (4') which is locked (9) to its wheel pair (2).

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Hyvinkaa, Finland

Jorma Surakka