DE1704095A1 - Drum for molding depressions in thermoplastic films - Google Patents

Description

47-04095

HÖFLIGER + KARG Waiblingen near Stuttgart Heerstrasse, P.O. Box 118

PB-Mr. 138 Waiblingen, January 20, 1967

Dr. Wolf A.

Drum for molding recesses in thermoplastic films

The invention relates to a revolving drum provided with recesses for forming recesses for items to be filled in thermoplastic films, in which the recesses via channels periodically under the influence of a Vacuum and the special holding means for the-> Foil tape are assigned.

In a prior drum of this kind, the holding means are formed as a circumferential endless wire ropes, which are guided around the provided for this purpose old circumferential drum and the edges of the foil strip press sealingly against the drum "Such support means are expensive and take up a lot of space, especially for the Wire ropes a number of pulleys as well as tensioning devices are required. (DAS 1 118 444).

The invention is based on the object of creating holding means for the film strip which can be implemented with the least possible outlay and also do not take up any additional space. This object is achieved according to the invention in that the holding means are provided as in the drum .

109817/1631 BATH ORIGINAL

P B no. 138 - 2 -

See recesses are formed which are periodically and automatically connected to a vacuum source via connecting channels; will. It has been found to be advantageous to connect these recesses via bores to the vacuum connection to connect the recesses for the filling items, which are already required connection channels. So that's that Vacuum at the same time and for the same time both in the recesses for the items to be filled as well effective in the recesses for holding and tight application of the film or the film edges on the drum.

The invention and its mode of operation are described below with reference to the drawing, which illustrates an exemplary embodiment, explained in more detail.

Show it:

Fig. 1 is a front view of a drum, the upper half of which is shown in section (section A - B through Fig. 2);

Fig. 2 is a view of the drum shown partially in section in view A.

As can be seen from FIGS. 1 and 2, the drum 1, made of brass, aluminum or some other suitable material, contains recesses 2, which are provided evenly distributed on the drum circumference and of which two groups 3, 4, one behind the other, viewed in the axial direction of the drum three recesses are arranged each, each forming ^{a “line 11”.} For the sake of simplicity, only some of the recesses have been drawn. Each line formed from recesses is assigned a channel 5, which is connected to the individual recesses 2 via openings 6 The channels 5 periodically reach the area of the slot 7 in the feather during the rotation of the drum.

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BATH ^1A ^ * "'"' - ^:

PB no. 138 - 3 -

standing Hing 8 on which the face of the drum slides and which is connected to vacuum via line 9, likewise periodically they pass the valve slot 10, which is also present in the Sing 8 and which is blown through the line 11 is fed «On both sides of the cutouts 2 recesses 12, which are arranged evenly distributed on the drum circumference and which are provided via bores 13 also open into channels 5. To improve cooling, the drum has cooling fins 14 on the inner circumference. Wit 15 a heating device is designated.

The drum described works in connection with a foil wrapped around it as follows:

The film 16 running onto the drum and being carried along by it first passes through the heating zone 17 in which the film is heated to such an extent that it is in the plastic state necessary for vacuum curing. After entering the area of the slot 7, a vacuum builds up in the channels 5 as well as in the bores 12 and thus also in the recesses 2, under the effect of which corresponding foil areas are drawn into the recess 2 . Similarly, the film zones located above the recesses 12 are slightly pulled in this screwing in Λ, which on the one hand, a fixed stop or a defined position is reached and the film remains, so that no warping occurs etc. and, secondly, a tight contact the film on the drum surface is guaranteed. After the deformation process, the film leaves οie Trowel. Blown air then passes through the valve slot 10 into the channels 5 and into the recesses 2.

Expectations:

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BATH ORIGINAL

Claims (5)

PB-Mr. 138 - 4 - Claims Circumferential drum provided with recesses for forming recesses for items to be filled in thermoplastic films, in which the recesses via channels periodically under the influence of a Vacuum reach and the holding means for the film strip are assigned, characterized in that the Holding means are designed as recesses (12) provided in the drum (1), which are also periodically and automatically made via connecting channels (13 »5) a vacuum source can be connected. 2.) Drum according to claim 1, characterized in that one end face of the drum (1) on a stationary, ring provided with connections (9 »11) for vacuum and blown air and valve slots (7, 10) (8) .- directs. 3.) Drum according to claims 1 and 2, characterized in that that the recesses (2) for the product and the recesses (12) for holding and sealing Applying the film (16) to the drum (1) is assigned the same vacuum connection (7 »9). 4.) Drum according to claims 1-3, characterized in that the recesses (12) are provided in the two edge regions of the drum and at regular intervals along the entire circumference of the drum. 109817/1631 PB-Mr. 138 - 5 - 5.) Drum according to claims 1-4 »characterized in that the recesses (12), the bores (13) and the channels (5) periodically and automatically via the line (11) and the valve slot (10) Blown air can be connected. 109817/1631 Blank page