GB2101030A

GB2101030A - Apparatus for separating filled packs of plastics material from sheeting with which they have been sealed

Info

Publication number: GB2101030A
Application number: GB08214016A
Authority: GB
Inventors: Max Norbisrath
Original assignee: Kraemer and Grebe KG
Current assignee: Kraemer and Grebe KG
Priority date: 1981-05-13
Filing date: 1982-05-13
Publication date: 1983-01-12
Also published as: NL8201935A; GB2101030B; FR2505781A1; DK214382A; DE3118946A1; IT8248404A0; SE8202894L

Abstract

Apparatus for separating, either completely or partially, packs of synthetic plastics material which have been formed by deep drawing, filled and then sealed by a length of sheeting, the apparatus comprising a plate 12 mounting therebelow a steel strip cutting tool 8 and against which the sheeting can be pressed by means of a lower tool 9 constructed as a cutting collar arranged to engage around the packs. A travel limiting arrangement may be provided for the upward movement of the tool at the end of the punching position and the containers may be supported in the punching position by supporting tables. <IMAGE>

Description

SPECIFICATION Apparatus for separating filled packs of plastics material from sheeting with which they have been sealed This invention relates to an apparatus for separating packs of synthetic plastics material which have been formed by deep drawing, filled and then sealed by a length of continuous sheeting. The separation may be complete or partial so as to leave thin webs or perforations between individual packs.

.Previously proposed apparatus for effecting such separating is preferably but not exclusively arranged at the outlet of an automatic deep drawing and packing machine. In most cases, the apparatus comprises complete sets of punching tools, comprising male and female dies. Although such punching apparatus has a high quality of cut, it involves various serious disadvantages which are an obstacle to general use in automatic deep drawing packaging machines. Thus, one disadvantage is the considerable financial outlay for the production of the tools, especially since a second set always has to be kept in reserve for maintenance reasons. Secondly, conversion for format changes is time-consuming and makes considerable demands on the operating personnel.For this reason, complete punching sets are used relatively seldom in deep drawing automatic packaging machines, which have to carry out continually changing packing tasks.

Rounded corners can be produced also by joint use of toggle cutters and longitudinal cutting means. By toggle cutters there are meant in this context transverse cutters which operate with a squeezing cut method, rectilinearly, and with interposition of perforated pipe type tools. But the quality of cut is often inadequate, since it is difficult to adjust the longitudinal cut line precisely to the middle of the angle radii.

It is an object of the invention to construct an apparatus for effecting the separating specified in such manner that a high quality of cut is ensured with packs of any peripheral contour, using tools which have a long working life and low manufacturing costs.

According to the present invention there is provided apparatus for separating packs of synthetic plastics material which have been formed by deep drawing, filled and then sealed by a length of sheeting wherein the apparatus comprises a central plate mounting therebelow a steel strip cutting tool with its cutting edges directed downwardly and a lower yoke plate mounting a cutting collar for operative engagement with the cutting tool, the cutting collar being arranged to engage around the packs, and there being means for moving the cutting collar upwardly from below, the arrangement being such that a strip of joined packs passing between said plates can be separated into individual packs by moving the cutting collar upwardly into operative engagement with the cutting tool.

In this apparatus, the cutting collar is arranged as a lower tool on the lower transverse or yoke plate, whilst the steel strip cutting tool with its cutting edges directed downwardly is held below the central plate. During the cutting or punching stroke the cutting collar, engaging about the troughs of the packs, is guided from below against the seam region of the sheeting and pressed with these against the steel strip cutting tool so as to sever the sheeting and separate the individual packs.

Preferably a travel limiting arrangement for the cutting collar is provided at the end of the cutting position, the travel limiting arrangement preferably comprising at least two travel limiting blocks which are situated on the lower yoke plate and which are guidable to abutment with at least two abutment plates arranged below the central plate. Advantage ousiy the travel limiting blocks and the cutting collar are arranged to be at the same level above the yoke plate, and the abutment plates and the steel strip cutting tool are also arranged to be at the same level below the central plate.

Supporting tables for the packs are preferably arranged to support the packs from below when they are in the punching position, the cutting collar being formed with free spaces to accommodate the packs during a punching or separating operation. The tables have holders which extend through the lower yoke plate, and the holders can be secured on a crossmember supported in stationary manner by a frame. Preferably a hydraulic piston and cylinder unit is provided as the means for moving the cutting collar, the hydraulic cylinder being secured to an upper yoke plate whilst the piston rod is supported on the central plate.

The lower yoke plate is adapted to be guided in a parallel manner upwardly towards the central plate by means of guide rods which are connected with both yoke plates and which are mounted in the central plate. The guide rods are preferably held to be displaceable axially in the central plate by means of sliding sleeves.

In this way it has been possible to achieve the provision of an apparatus for detaching synthetic plastic material packs from webs of sheeting with a reliably high standard of operating reliability and long working life. The loop-shaped or collar-like lower tool is not subjected to any substantial wear, and can be produced inexpensively in a simple manner.

Steel strip cutting tools are used as the upper tool, these being punching cutters in wooden or plastics mounts, with relatively low production costs and a long working life.

Owing to the travel limiting arrangement which may be provided, the cutting edge of the cutting tool does not contact the cutting collar, so that this does not in the long run affect the sharpness of the cutting tool. The steep strip cutting tools are adaptable readily to the outer contours of any forms of packs.

The present apparatus is also suitable for the provision of perforations, which has not been possible with complete sets of punching apparatus.

In order to enable the invention to be more readily understood reference will now be made to the accompanying drawings, which illustrate diagrammatically and by way of example an embodiment thereof, and in which: Figure 1 is a side view partly in section of apparatus for separating packs of deep drawn plastics material which have been filled and then sealed by a length of continuous sheeting, the apparatus being shown in an opened position, Figure 2 is a cross-section through the apparatus shown in Fig. 1, in a punching position, and Figure 3 is a plan view of the apparatus shown in Figs. 1 and 2, partly in section.

Referring now to the drawings, there is shown apparatus for separating filled packs 2 from a length of sheeting with which they have been sealed. The apparatus is preferably situated at the outlet of an automatic deep drawing packing machine in which the packs have been formed by deep drawing, have been filled and then sealed by the sheeting, that is to say that the apparatus is situated downstream of the sealing station for the upper sheeting in the direction of travel of the packs through the machine. The apparatus is mounted on a lower frame 20 standing on anti-vibration feet 21 and includes a column guide frame comprising a central plate 12, a lower yoke plate 13, an upper yoke plate 1 4 and guide columns 1 5 which are slidably mounted in sleeves 1 6 arranged in the central plate 12.

The lower frame 20 is situated at the two sides of a frame 1 9 of the packing machine.

The transport chains 1 for conveying the filled and sealed packs from the automatic packaging machine travel between the central plate 1 2 and the lower yoke plate 13, so that the sheeting with the filled packs 2 is conveyed at the machine rhythm, over a preferred length at a time, into punching positions 3 for the packs.

In a punching operation to separate the packs from the continuous sheeting with which they are sealed, the lower yoke plate 1 3 is guided upwardly by means of the guide columns 1 5 and the upper yoke plate 14 which is acted upon by a hydraulic cylinder 1 7 and a piston rod 1 8. A cutting collar or hollow punch 9 constituting a lower tool accommodates the packs 3 in its central free spaces there being four such spaces as can be seen from Fig. 3, and then presses the sheeting in these regions where it has been welded to the packs 2 against a steel strip cutting tool 8, so that the packs are separated from the sheet, or detached.In this operation, the bases of the packs lie on supporting tables 22 which are arranged below the punching position 3 in the central free spaces of the cutting collar 9. The supporting tables 22 are supported by vertical holders 23 each of which extends through a respective bore in the lower yoke plate 1 3. The lower ends of the holders 23 are secured on a cross member 24 which is connected with the frame 1 9 of the packaging machine.

The travel of the cutting collar 9 towards the cutting tool 8 is dimensionally limited by the impingement of travel limiting blocks 10, secured on the lower yoke plate 13, against abutment plates 11 held by the central plate 1 2 in such a manner that the sheet material is severed completely but that the cutting edge of the tool 8 is not detrimentally affected by the cutting collar 8. The cutting tool 8 and the abutment plates 11 depend exactly the same depth below the central plate 1 2 and the cutting collar 9 and the travel limiting blocks 10 extend for exactly the same hoight above the yoke plate 1 3.

The sheeting network 5 remaining between the individual packs from the punching operation is released after the punching station from the sheeting transport chain 1 and drawn off and reeled by means of a sheeting network winding device 6. A conveyor belt (7) at the outlet from the apparatus serves to convey the separated packs 4 from the machine.

By providing apertures in the cutting edge of the cutting tool 8 it is possible to leave connecting webs between the individual punched-out packs 4, which can simplify the delivery of the packs.

The hydraulic drive for the punching operation is in the form of a hydraulic system comprising a motor 29 and a hydraulic pump 28 which is situated in a hydraulic fluid container 30. The hydraulic system also includes a pressure-limiting valve 31, a manometer 32, a magnetically operated control valve 27, flexible conduits 26 and hydraulic conduits 25 to the hydraulic cylinder 1 7.

Electrical control is in accordance with the sequence of operating functions of the automatic deep-drawing packaging machine.

Claims

1. Apparatus for separating packs of synthetic plastics material which have been formed by deep drawing, filled and then sealed by a length of sheeting, wherein the apparatus comprises a central plate mounting therebelow a steel strip cutting tool with its cutting edges directed downwardly and a lower yoke plate mounting a cutting collar for operative engagement with the cutting tool, the cutting collar being arranged to engage around the packs, and there being means for moving the cutting collar upwardly from below the arrangement being such that a strip of joined packs passing between said plates can be separated into individual packs by moving the cutting collar upwardly into operative engagement with the cutting tool.

2. Apparatus as claimed in Claim 1, wherein a travel limiting arrangement is provided for the cutting collar at the end of the cutting position.

3. Apparatus as claimed in Claim 2, wherein the travel limiting arrangement comprises at least two travel limiting blocks which are situated on the lower yoke plate and which are adapted to be guided to abut with at least two abutment plates situated below the central plate.

4. Apparatus as claimed in Claim 3, wherein the travel limiting blocks and the cutting collar are arranged to be at the same level above the yoke plate.

5. Apparatus as claimed in Claim 3 or 4, wherein the abutment plates and the steel strip cutting tool are arranged to be at the same level below the central plate.

6. Apparatus as claimed in any one of the preceding claims, wherein the cutting collar is formed with free spaces to accommodate the packs during a separating or punching operation and wherein supporting tables are arranged in such free spaces of the cutting collar to support the packs, the tables having holders which extend through the lower yoke plate.

7. Apparatus as claimed in Claim 6, wherein the holders are secured on a crossmember supported in stationary manner by a frame.

8. Apparatus as claimed in any one of the preceding claims, wherein the means for moving the cutting collar is a hydraulic piston and cylinder unit.

9. Apparatus as claimed in Claim 8, wherein the hydraulic cylinder is secured on an upper yoke plate whereas the piston rod bears on the central plate and wherein the lower yoke plate is adapted to be guided in a parallel manner upwardly towards the central plate by means of guide rods which are mounted in the central plate and are connected with both yoke plates.

10. Apparatus as claimed in Claim 9, wherein the guide rods are held so as to be axially displaceable in the central plate by means of sliding sleeves.

11. Apparatus as claimed in any one of the preceding claims, wherein the cutting tool and cutting collar are each interchangeably mounted.

1 2. Apparatus for separating packs of synthetic plastics material which have been formed by deep drawing, filled and then sealed by a length of sheeting substantially as hereinbefore described with reference to the accompanying drawings.