GB2068821A

GB2068821A - Improvements in or relating to a receptacle

Info

Publication number: GB2068821A
Application number: GB8101872A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1980-02-06
Filing date: 1981-01-22
Publication date: 1981-08-19
Also published as: NL8100522A; DK49281A; NO810398L; IT1135346B; FR2474943A1; SE8000959L; IT8119573A0; JPS56127433A; DE3103225A1

Abstract

In producing a receptacle a web of plastics material is moulded so that the web forms a receptacle with a liquid-tight side wall, and the formed receptacle is severed from the rest of the web by means of cooperating elements movable relatively to one another and simultaneously one or more apertures are formed in the base of the receptacle. A filter disc may be located within the receptacle. In the embodiment of Fig. 3, a sheet (9) is vacuum moulded in a mould (7) and the resultant article is severed from the sheet by a first blade (13) acting against a resilient counter (10). An aperture is simultaneously formed in the base of the article by a second blade (14) acting against a second counter. A filter disc is located over the aperture. In the embodiment of Fig. 7, each of a pair of vacuum moulds has a resilient cushion (24) in its base and the base of the freshly formed article is perforated by a member (12a, 12b) carrying pins (22) which is movable into the mould. <IMAGE>

Description

SPECIFICATION Improvements in or relating to a receptacle This invention relates to a receptacle, and more particularly to a disposable receptacle.

There is a need for cheap receptacles especially receptacles which are partially permeable to constitute inserts for providing controllable filtering or separation, and for use as filters in industrial processes, and in air cleaning facilities, such as air filters for motor vehicles, in percolation or strainer systems, and in other kinds of separating facilities.

There is also a requirement for receptacles for use as flower or plant pots.

According to this invention there is provided a method of producing a receptacle comprising the steps of moulding a web of plastics material in a moulding tool at a moulding station so that the web forms a receptacle with a liquid-tight side wall, and severing the formed receptacle from the rest of the web by means of co-operating elements movable relatively to one another, wherein, in connection with or after the moulding step the receptacle is provided with a permeable or semi-permeable base portion.

Said receptacles may be moulded from a heated web of a thermo-plastics material which is advanced intermittently to the moulding station, and preferably one or more moulding tools are brought to an operative position at the moulding station so that a receptacle may be moulded therein, and simultaneously moulding or shaping tools that were previously at the moulding station are moved to a delivery position so that receptacles moulded therein can be removed therefrom. Conveniently the moulding tool may comprise a recess in a tool, there being means for evacuating the recess so that the web of material is vacuum formed. Advantageously said receptacle is severed from the web by a cutting blade which co-operates with a resilient abutment surface in the moulding tool, and preferably said cutting blade is heated.

In one embodiment of the method a receptacle having an integral base is formed, perforations being formed in the base of the receptacle. The step of perforating the base may be carried out in the moulding tool and may be performed by means of heated spikes which cooperate with a resilient abutment surface forming part of the moulding tool.

Preferably the perforating step is carried out simultaneously with the step of severing the moulded receptacle from the rest of the web.

Alternatively the perforating step may be carried out ultrasonically against a rigid support surface.

In another embodiment of the method the base of the receptacle is stamped out entirely or partly in the moulding tool, and the stamping out may be performed simultaneously with the severing of the receptacle from the rest of the web. Preferably the base of the receptacle is stamped out by a cutting edge which co-operates with a resilient abutment surface in the moulding tool.

The base of the recess in the moulding tool in which the receptacle is formed may be provided with an aperture, and means may be provided for connecting the aperture to a source of vaccum or partial vacuum so that, after the stamping out of the base of the receptacle the cut-out base may be removed from the moulding tool by the vacuum or partial vacuum. Preferably a control valve is provided between the said aperture and the source of vacuum or partial vacuum. Whilst the perforations, or the apertures formed in the base of the receptacle render it permeable it is preferred that the perforations or apertures formed in the base of the receptacle are covered by a gas- or liquid-permeable element, such as a filter element comprising filtering paper which may be secured to the receptacle by thermo-welding or by adhereing.

Preferably the method includes the steps of providing a receptacle with a peripheral outwardly directed bulge located at a distance from the top of the receptacle to facilitate stacking. The method may include the step of providing the receptacle with rigid substantially horizontally outwardly extending protrusions, the resultant receptacle being suitable for use as a tea strainer, coffee infuser or the like. The receptacle may be provided with stiffening or strengthening members which extend along the base of the receptacle, and is preferably provided with a radially outwardly peripherally extending flange at the top part thereof.

This invention also relates to a receptacle whenever manufacture by a method as described above.

In order that the invention may be more readily understood, and so that further features thereof may be appreciated, the invention will now be described by way of example with reference to the accompanying drawings in which: Figure 1 is a perspective view of a receptacle with a permeable base made in accordance with the invention, with part thereof cut away; Figure 2 is a plan view of the receptacle shown in Fig. 1; Figure 3 is a vertical sectional view showing a moulding or shaping tool, and showing a stamping tool cooperating therewith, the tools being used for the production of a receptacle as shown in Figs. 1 and 2; Figure 4 is a vertical section through part of the moulding tool shown in Fig. 3; Figure 5 is a vertical sectional view through the moulding tool of Figs. 3 and 4 showing a further tool for introducing a prefabricated porous base element into the receptacle;; Figure 6 is a vertical sectional view corresponding to Fig. 5 showing how the further tool can cooperate with a stamp or punch to prepare the prefabricated porous base element; Figure 7 is a vertical sectional view through a further tool for manufacturing receptacles in accordance with the invention illustrating how the receptacles are provided with a perforated base; Figure 9 is a perspective view of an inverted receptacle made on the tool illustrated in Fig. 7; Figure 9 is a perspective view of a further receptacle made in accordance with the invention; Figure 10 is a perspective view of yet a further receptacle made in accordance with the invention, the receptacle comprising a tea strainer, and Figure 11 is a perspective of yet a further receptacle made in accordance with the invention for use as a flower or plant pot.

With reference to the accompanying drawings initially a receptacle which has a permeable base and which has been manufactured in accordance with the invention will be described with reference to Figs. 1 and 2. The receptacle 1 is circular in plan and has a side wall 1 a which tapers conically from a top radially outwardly directed collar or flange 2 towards a bottom radially inwardly extending collar or flange 3. The wall 1 a is made of a thermoplastics material and is homogenous and is not permeable. Thus the wall is gasand liquid-tight. The inwardly directed collar or flange 3 defines a circular aperture 4 in the middle of the base of the receptacle 1.A circular disc of gas or liquid permeable material, such as a disc of porous paper or the like, the disc having a greater diameter than the diameter of the aperture 4, is secured to the flange 3 by means of adhesive or by heat sealing around its peripheral edge 6 to the flange 3, so that the aperture 4 is closed. The disc 5 serves, in this receptacle, as a filter element.

Whilst, in the receptacle illustrated in Figs.

1 and 2, the aperture 4 formed in the base of the receptacle is covered by a gas or liquid permeable material it is to be understood that a receptacle made in accordance with the invention can simply have an exposed aperture which can extend over the whole of the base surface, or just over a part of the base surface, or alternatively the base surface of the receptacle may be provided with a plurality of small apertures or perforations. Thus the side wall and the base of the receptacle can be made as a unitary construction, for example the thermoplastics material, the base of the receptacle being provided with a large number of fine perforations by appropriate means during or after the shaping or moulding step.

Having now described products manufactured by processes in accordance with the present invention, one particular process will now be described with reference to Figs. 3 to 5 of the accompanying drawings.

Fig. 3 illustrates a vacuum forming tool 7.

The tool defines a recess in its upper surface, and is provided with ducts 8 which communicate with the recess and which serve to extract air from the recess. In utilising the tool a web 9 of thermoplastics material is heated and is advanced intermittently to the illustrated moulding station, where, as will be described hereinafter it is heat moulded and stamped by cooperating elements which mov'e relative to one another. In a preferred machine for performing the process in accordance with the invention two moulding tools 7 are utilised, one tool being brought to the operative position at the moulding station to be used in the manufacture of a receptacle whilst the second moulding tool is simultaneously moved to a delivery position where a receptacle manufactured within the tool is removed from the tool.However, again referring to Fig. 3, as the heated web of thermoplastics material 9 is brought to the moulding station and air is withdrawn from the recess defined in the tool 7 through the ducts 8, the heated material is drawn into the recess and thus adopts the configuration corresponding to the configuration defined by the recess, which is, of course, the configuration of the receptacle. As can be seen from Fig. 3, two grooves are formed in the tool 7, one groove being located in the upper surface of the tool surrounding the periphery of the recess, and the other being formed in the portion of the tool defining the recess. These grooves contain infills of resilient material 10, 11. A stamping tool 12 is provided adapted to stamp and cut the thermoplastics material web 9 when it has been moulded. The stamping and cutting tool 12 includes two circular cutting blades 13, 14.The cutting blade 13 is aligned with the resilient infill 10 and the cutting blade 14 is aligned with the resilient infill 11. As the stamping and cutting tool 12 is moved downwardly the cutting blade 13 cuts through the thermoplastic material web 9 where the web 9 is in contact with the resilient infill 10, and thus serves to separate the receptacle from the remainder of the web 9. The second cutting blade 14 cuts through the moulded portion of the web in the region that contacts the resilient infill 11, thus cutting a circular disc from the base of the receptacle, consequently defining the aperture 4 that is in the base of the receptacle. Since the two cutting blades 13, 14 cut through portions of the web that are supported by the resilient infills 10, 11 the stamping and cutting step can take place simultaneously at two staggered levels. This is almost impossible conventional stamping methods in which a severing stamping step is carried out against a hard or rigid abutment surface. The above described method of using resilient abutment surfaces allows a relatively high tolerance between the positioning of the two abutment surfaces. It has been found that differences up to several tenths of a millimetre do not detract from a satisfactory stamping-out step. Preferably, however, the cutting edges 13, 14 are heated since this facilitates the operation of the device.

As can be seen from Fig. 3 the bottom of the recess formed in the tool 7 is provided with an open aperture 15. As can be seen in Fig. 4 this aperture 15 is connected to a conduit 16 in which there is mounted an appropriate valve 17. The conduit 16 is connected to a source of vacuum or partial vacuum, such as a fan. During the above-described vacuum moulding step the valve 17 is kept closed. Since a certain amount of air is present in the conduit 16 between the closed valve 7 and the recess in the mould the portion of the web 9 is drawn down to the base of the recess in the mould 7 is not sucked down through the aperture 15, but remains in a substantially planar configuration.It is to be noted that this base part does not remain completely flat but usually forms a slightly downwardly directed bulge 18 since this part of the web 9 does not have any surface to support it during the moulding step. However this is of little significance since, as will now be described, this part of the web is removed and does not form part of the finally manufactured receptacle.

Upon completion of the stamping step the valve 17 is opened. The vacuum or partial vacuum thus communicates with the aperture 15 and because of the difference between the pressure of the interior of the recess and the mould 7 and the pressure within the conduit 16 the punched-out disc 18 is drawn through the conduit 16, past the valve 17 to an appropriate collecting facility.

The above described moulding process thus provides a receptacle formed integrally of a thermoplastics material having a side wall an upper outwardly directed flange and a lower inwardly directed flange. It will be appreciated that by utilising the above described process receptacles can be produced with considerable accuracy with the upper and lower flange properly centred and with the bottom central disc punched out accurately. However the receptacles can be produced rapidly and cheaply.

A disc 5, for example a disc to act as a filter element as described with reference to Figs. 1 and 2, can readily be connected to the receptacle manufactured as described above. As shown in Fig. 5 a tool 19 may be utilised which has a circular portion supporting a disc 5, the portion of the tool 19 supporting the disc being heated. The tool can be moved so that the periphery of the disc 5 is brought into contact with the inwardly directly flange formed at the base of the receptacle, and, by virtue of the fact that the tool is heated, the disc 5 will be thermo-welded to the receptacle.

As is shown in Fig. 6, if desired the tool 19 can initially be provided with a sheet 20 of paper or the like to form the disc 5 which is over-sized. The tool 19, together with the sheet 20 can then pass through a stamp 21 which is located above the tool 7, the stamp 21 and the tool 19 cooperating to provide a disc 5 of the desired size. The tool 19 can also be used as an element for sorting and stacking the receptacles after their manufacture, if desired.

Turning now to Fig. 7 of the accompanying drawings a further tool for use in a process in accordance with the present invention is illustrated. The illustrated tool 7 has two recesses into which elements of a heated thermoplastics material web 9 can be drawn by a vacuum. A cutting and stamping tool 12 is provided having heated cutting edges 13, 1 3a corresponding to those described above, which cut through regions of the web which are supported by resilient abutment surfaces.

However, in the illustrated arrangement the tool 12 is provided with two perforating elements 1 2a 1 2 b, each perforating element comprising a disc shaped member provided with a plurality of downwardly directed heated spikes 22, which are adapted to be inserted into the material defining the base of the receptacle, whilst the receptacle is still in the mould. The base of the recess defined in the mould 7 is formed from a resilient material 24. It will be appreciated that in utilising the tool illustrated in Fig. 7 perforations are formed in the base of the manufactured receptacles simultaneously with the severing of the receptacles from the rest of the web 9. Fig. 8 illustrates a receptacle manufactured by the tool illustrated in Fig. 7 and shows the perforations 20 formed in the base of the receptacle.

It is to be appreciated that the perforations 20 formed in the base of the receptacle can be formed by perforating against a rigid support surface and can thus be formed ultrasonically. The perforating step can also be performed at a station which is separate from the moulding station. Alternatively the perforating tool can be located at the delivery station where the manufactured receptacles are removed from the mould, and can thus be combined with a stacking facility instead of being combined with the stamping function as illustrated in Fig. 7.

Fig. 9 illustrates a further embodiment of a receptacle manufactured in accordance with the invention, the receptacle being of generally rectangular configuration and having reinforcing or strengthening ribs 21 extending across its base surface. Conveniently the base parts 23 can be wholly or partly stamped out during the manufacture of the receptacle, or these parts may be perforated. In any event the regions of the base between the reinforcing elements 21 can be covered by a gas or liquid pervious material.

Fig. 10 illustrates a further embodiment of a receptacle manufactured in accordance with the invention, the illustrated receptacle being intended for use as a tea strainer. It is to be noted that two substantially rectangular horizontal protrusions 25, 26 are formed integrally with the side wall of the receptacle 1, and are rigid enough to spend the receptacle over a vessel such as a tea cup whilst it is used as a tea strainer.

It is to be appreciated that the receptacle shown in Fig. 10 can also be used as an infuser. Thus, for example, the receptacle can be filled with an appropriate quantity of material for extraction, such as coffee, and subsequently a liquid-permeable cover, in the form of an appropriate sheet, can be mounted in position over the open upper mouth of the receptacle. Subsequently coffee can be prepared by pouring boiling water through the liquid permeable cover sheet, and thus through the coffee contained within the receptacle, the infused water leaving the receptacle through the permeable base. Of course, materials other than coffee can be extracted or infused in this way.

Fig. 11 illustrates yet a further receptacle made by a process in accordance with the invention, the illustrated receptacle 27 comprising a pot for containing seedlings or plants. Four holes 28 are provided in the base of the receptacle. When the receptacle is in use, that is to say when plants or seedlings are growing in the receptacle, the receptacle will be held in an appropriate holder.

It will be appreciated that the invention has been described above with reference to simple embodiments of moulding tool. It is to be appreciated that the moulding tools may be provided with conventional cooling means.

Also, whilst the invention has been described with reference to tools having one or two recesses, tools can be devised having a large number of recesses. Thus it is envisaged that a moulding machine can be devised in which, for example, sixty four receptacles can be produced in a four-second long moulding cycle. This corresponds to an overall production rate of 960 receptacles per minute. It will readily be appreciated that this level of output makes the cheap mass production of receptacles possible.

The receptacles may be made with a bulge in the side wall to facilitate stacking of the receptacle.

It is to be understood that the invention is not limited to the specific embodiments illustrated and can vary in many ways without parting from the scope of the following

Claims

claims. It is to be emphasised that a receptacle can be of any appropriate cross section, not only circular or rectangular, and also the base surface of a receptacle does need to be planar. Receptacles in accordance with the invention can be manufactured so cheaply that they can be considered to be disposable receptacles. CLAIMS

1. A method of producing a receptacle comprising the steps of moulding a web of plastics material in a moulding tool at a moulding station so that the web forms a receptacle with a liquid-tight side wall, and severing the formed receptacle from the rest of the web by means of co-operating elements movable relatively to one another, wherein, in connection with or after the moulding step the receptacle is provided with a permeable or semi-permeable base portion.

2. A method according to claim 1, wherein said receptacle is moulded from a heated web of a thermo plastics material which is advanced intermittently to the moulding station.

3. A method according to claim 1 or claim 2, wherein one or more moulding tools are brought to an operative position at the moulding station so that a receptacle may be moulded therein, and simultaneously moulding or shaping tools that were previously at the moulding station are moved to a delivery position so that receptacles moulded therein can be removed therefrom.

4. A method according to any one of the preceding claims wherein the moulding tool comprises a recess in a tool, there being means for evacuating the recess so that the web of material is vacuum formed.

5. A method according to any one of claims 1 to 4 wherein said receptacle is severed from the web by a cutting blade which co-operates with a resilient abutment surface in the moulding tool.

6. A method according to claim 5 wherein said cutting blade is heated.

7. A method according to any one of the preceding claims wherein a receptacle having an integral base is formed, perforations being formed in the base of the receptacle.

8. A method according to claim 7 wherein the step of perforating the base is carried out in the moulding tool.

9. A method according to 8 wherein the step of perforating the base is performed by means of heated spikes which cooperate with a resilient abutment surface forming part of the moulding tool.

10. A method according to claim 9 wherein the perforating step is carried out simultaneously with the step of severing the moulded receptacle from the rest of the web.

11. A method according to claim 7 or 8 wherein the perforating step is carried out ultrasonically against a rigid support surface.

12. A method according to any one of claims 1 to 6 wherein the base of the receptacle is stamped out entirely or partly in the moulding tool.

13. A method according to claim 12 wherein the base of the receptacle is stamped out simultaneously with the severing of the receptacle from the rest of the web.

14. A method according to claim 13 wherein the base of the receptacle is shaped out by a cutting edge which cooperates with a resilient abutment surface in the moulding tool.

15. A method according to claim 14 wherein the cutting edge which stamps out said base is heated.

16. A method according to any one of claims 12 to 15 wherein the base of the recess in the moulding tool in which the receptacle is formed is provided with an aperture, and means are provided for connecting the aperture, and means are provided for connecting the aperture to a source of vacuum or partial vacuum so that, after the stamping out of the base of the receptacle the cut-out base is removed from the moulding tool by the partial vacuum.

17. A method according to claim 16 wherein a control valve is provided between the said aperture and the source of vaccum or partial vacuum.

18. A method according to any one of claims 1 to 17 wherein the perforations or apertures formed in the base of the receptacle are covered by a gas-or liquid-permeable element.

19. A method according to claim 18 wherein the perforations or apertures formed in the base are covered by a filter element.

20. A method according to claim 19 wherein the filter element comprises filter paper.

21. A method according to any one of claims 18 to 20 wherein the gas- or liquidpermeable element is secured to the receptacle by thermo-welding.

22. A method according to any one of claims 18 to 20 wherein the gas- or liquidpermeable element is secured to the receptacle by adhering.

23. A method according to any one of the preceding claims including the step of providing a receptacle with a peripheral outwardly directed bulge located at a distance from the top of the receptacle to facilitate stacking.

24. A method according to any one of the preceding claims comprising the additional step of providing the receptacle with rigid substantially horizontally outwardly extending protrusions.

25. A method according to any one of the preceding claims including the step of providing a receptacle with stiffening or strengthening members which extend along the base of the receptacle.

26. A method according to any one of the preceding claims wherein the receptacle is provided with a radially outwardly peripherally extending flange at the top part thereof.

27. A method of manufacturing a receptacle substantially as herein described with Figs.

1 to 5 of the accompanying drawings.

28. A method of manufacturing a receptacle substantially as herein described with reference to Figs. 1 to 5 of the accompanying drawings as modified by Fig. 6.

29. A method of manufacturing a receptacle substantially as herein described with reference to Figs. 7 and 8 of the accompanying drawings.

30. A receptacle whenever manufactured by a method according to any one of the preceding claims.

31. A receptacle substantially as herein described with reference to and as shown in Figs. 1 and 2 of the accompanying drawings.

32. A receptacle substantially as herein described with reference to and as shown in Fig. 9 of the accompanying drawings.

33. A receptacle substantially as herein described with reference to and as shown in Figs. 10 of the accompanying drawings.

34. A receptacle substantially as herein described with reference to and as shown in Fig. 11 of the accompanying drawings.

35. Any novel feature or combination of features disclosed herein.