US3868893A

US3868893A - Apparatus for producing composite containers

Info

Publication number: US3868893A
Application number: US405103A
Authority: US
Inventors: Brian Leo Chudleigh Sutch
Original assignee: Airfix Industries Ltd
Current assignee: PATENT DEVELOPMENTS INTERNATIONAL Ltd
Priority date: 1972-10-10
Filing date: 1973-10-10
Publication date: 1975-03-04
Anticipated expiration: 1992-03-04
Also published as: IL43412A; IE38866B1; AU6122073A; CH577888A5; ATA862273A; FI55626C; ES419521A1; FI55626B; IE38866L; FR2202467A5; NO139880B; NL166429C; LU68597A1; DE2350810A1; NO139880C; DK138037C; NL166429B; AT340758B; JPS49101182A; CA995065A

Abstract

Apparatus to produce a composite container from a blank defining a base panel from each of opposite sides of which projects a side panel, the apparatus having a split cavity tool, a core tool and a guideway to position a blank between the tools when they are open, closure of the tools driving the base panel toward the cavity tool and thereby initiating folding of the side panels relative to the base panel.

Description

United States Patent 1191 [111 3,868,893

Sutch Mar. 4, 1975 APPARATUS FOR PRODUCING [56] References Cited COMPOSITE CONTAINERS UNITED STATES PATENTS I ve tor; Brian Leo Sutch, Thames l,l54,969 9/1915 Burnham 93/51 R Ditton, England 1,679,985 8/1928 2,925,758 2/l960 [73] Assignee: Airfix Industr es m n, 3,618,482 11/1971 Bowman 93/51 R England Primary E.\'aminerRoy Lake 7 Filed 1973 Assistant E.\'aminerNeil Abrams {21] Appl. No.: 405,103 Attorney, Agent, or FirmScrivener Parker Scrivener and Clarke [30] Foreign Apphcatlon Priority Data ABSTRACT Oct, 10. l972 Great Britain 46582/72 Mar. 22 1973 Great Britain 14015/73 Apparatus produce a comlmsue comma from a blank defining a base panel from each of opposite [5.)] U S Cl 93/50 93/36 MM 93/363 sides of which projects a side panel, the apparatus 93/51 R 93/59 having a split cavity tool, a core tool and a guideway {51] Int Cl B3) U44 B3lb N62 to position a blank between the tools when they are [58] Field o't'sgg'r'n; 65 R 49 g 50 51 R open, Closure of the tools driving the base panel to- 93/59 CE, 59 ES, 59 PL, 36 MM, 36.3; 53/192, 207, 209

ward the cavity tool and thereby initiating folding of the side panels relative to the base panel.

10 Claims, 14 Drawing Figures PAHENIEDMAR 4|975 SHEET 2 OF 7 F/GJ.

PATENTEDHAR 41915 3,868,893

sum 3 o 1 PATENTEDHAR 5. 8.888.888

snznsu g F/GJO.

APPARATUS FOR PRODUCING COMPOSITE CONTAINERS This invention is concerned with improvements in and relating to apparatus for producing composite containers, that is to say containers which are formed of a foil blank, the foil being for example of metal, paper, card, synthetic plastics sheet, or any other suitable material, which is formed to the desired shape and then seamed along juxtaposed edges by a material, preferably a synthetic theremoplastics material, which can be applied as for example by injection moulding.

According to this invention there is provided apparatus for producing a composite container from a blank comprising an end wall panel and side wall panels each of which projects from the end wall panel, the apparatus comprising a guide by which the blank end wall panel can be positioned between a relatively movable core tool and a split female tool which tools are movable relative to one another, relative movement toward one another being operative in relation to a blank positioned by the guide, to drive the end wall panel relative to the side wall panels relative to the guide and into the split tool and to cause relative movement of the parts of the split tool toward one another, so that the core tool and the split tool define a cavity in which the blank will be trapped in the desired shape, means being provided to seam juxtaposed edges of the so trapped blank.

The split tool preferably includes a base tool relative to which the tool halves are movable and which with the core tool and split tool halves defines the cavity.

This invention is concerned with improvements in and relating to apparatus for producing composite containers, that is to say containers which are formed of a foil blank, the foil being for example of metal, paper, card, synthetic plastics sheets, or any other suitable material, which is formed to the desired shape and then seamed along juxtaposed edges by a material, preferably a synthetic thermoplastics material, which can be applied as for example by injection moulding.

The split tool preferably includes a base tool relative to which the tool halves are movable and which with gages the base tool and will then retract into the core tool as this continues its relative advance toward the base. Preferably the blank is engaged by the forward end of the core tool and vacuum means are provided in that face.

The split tool parts preferably have a length in relation to the depth of the finished container such that the end of the container blank which is remote from the base tool is within the length of the split tools, which will clamp that end of the container blank hard against the core at a position forward, i.e., nearer the base tool, than the stripper plate or a stripper ring extending round the core tool. Thereby the side wall panel free edges remote from the base tool, as they approach one another, will have a path forward of the stripper plate and will not foul that plate.

In order that the invention may be well understood, there will now be described some embodiments thereof, given by way of example only, reference being made to the accompanying drawings in which:

FIG. 1 is a plan view of a blank;

FIG. 2 is a perspective view of a completed container;

FIG. 3 is a diagrammatic vertical section through the tools during closing;

FIG. 4 is a diagrammatic horizontal section through the tools during closing;

FIG. 5 is a vertical section of a pair of guide rails looking away from the cavity tool;

FIG. 6 is a vertical section of a pair of guide rails including means to centre a blank;

FIG. 7 is a horizontal sectional view of a form of guide rails for a multi-impression tool;

FIG. 8 is a side elevation of core support plate, stripper plate, blank guide, split tool halves and base tool of a three impression tool for making the container of FIG. 2 with the blank of FIG. 1;

FIG. 9 is an elevation of the guide rails viewed in the direction of arrow A of FIG. 8;

FIG. 10 is a section along the line X-X of FIG. 11 through the three impression tools when closed;

FIG. 11 is a front elevation of the split tool halves in the open condition;

FIG. 12 is a detail horizontal section of a core tool;

FIG. 13 is a detail of a split tool, and

FIG. 14 is a schematic plan view of a magazine.

The tool shown in FIGS. 3 to 7 is intended for a single impression machine to operate on blanks such as shown in FIG. 1 to produce a container as shown in FIG. 2. The blank is for example cardboard and, includes a base panel B and side panels S and fold lines F in the side panels delimit wing panels W. When folded up to make a container, edges E are juxtaposed with edges E and edges G with edges G. In each cycle the machine folds a blank and forms a seam H along each pair of juxtaposed edges and a lip L, by injection moulding. The seam H at the base panel may extend round that panel as shown in FIG. 2. The machine comprises a core tool 10 on a support plate 11, blank guide rails l2, 13, a split

female tool

14, 15 and a base tool 16. The core tool has one or more vacuum openings 10a opening at the leading face 10b, the face nearest the base tool, and coupled in any suitable way by passages l0c with a vacuum source.

The operation of the machine will be apparent from FIGS. 3 and 4. With the core tool 10 fully retracted to the open condition, FIG. 3(a) and FIG. 4a, away from the base tool 16 a blank x is delivered down the

guide rails

12, 13, the wings W of the side panels S of the blank engaging in grooves 12a, 13a of the guide rails and being positioned above and below the base panel B whose free edges are clear of the rails. This position of the blank is also seen in FIGS. and 6. The blank is supported in this position with the base panel B opposite the core tool by a suitable stop 12' adjustably secured to one rail. When the core tool advances the leading face abuts the base panel b and the vacuum openings hold the base panel relative to the leading face. As the core tool continues its advance, the base panel moves out of the plane of the guide rails, see the broken line position of core tool 10 in FIG. 3(a) and FIG. 4a, but the side panel wings W tend to hang back due to their engagement in the side rails. Thus hinging of the side panels relative to the base panel starts.

Further advance of the core tool will carry the base panel to the plane of the leading

end faces

14a, 15a of the split female tool halves which is the ultimate axial position of the base panel relative to the split tool, FIG, 3(b) and FIG. 4(b). At this stage, leading face 41a of a stripper ring 41 which has passed between the rails abuts the rear faces of the split tool halves. The split tool halves are still spaced in the vertical plane from the core tool and the blank side panels S and wings W which are indicated in chain dot line in FIG. 3(b) are in the spaces between the core tool and split tool halves. Further advance of the core tool now carries the base panel to the base tool face 16a and moves the

split tool halves

14, 15 up to the base tool. Being carried on converging slideways the split tool halves l4, 15 move toward one another in the vertical plane and toward the core tool and complete the folding of the side panels relative to the base panel. There is no relative axial movement of the split tool halves and core tool in this final stage which is advantageous in the case of containers having a very small taper angle say of less than 2%".

In the progressive closing movement of the core tool, the core tool and then the ring 41 pass between the guide rails. To allow the completion of the closing movement, the guide rails are displaceable by a stripper plate 41b which is much wider than the spacing between the rails. For a very shallow draft container, e.g. of a draft less than the depth of the stripper ring, the guide rails might be stationary.

To provide clearance of the blanks from the bottoms of the guide rail channels adequate to ensure a rapid free fall ofthe blanks down the guide rails, and the centering of the blanks for the core tool, the arrangement of FIG. 5 may be adopted. The wings of one side panel S at the free edge are narrower than the wings on the other side panel at the free edge by virtue of flats 3b (FIG. I). The narrower free edge is lowermost when the blank is fed down the guide rails. A pair of cam faces 12b, 13b, 12c and 130 are provided in each rail channel. Now when the blank drops, the lowermost wings clear the rail bottoms at the region of the upper cam faces 12b, 13b and have free travel down the rails below those faces. However on reaching cam faces 12c, 13c the wings adjacent the lowermost free edge bind on those faces and the energy of the blank causes it to bow slightly and therefore the blank is accurately centred. Likewise the upper free edge which clears the rail bottoms above cam faces 12b, 13b engages those faces and centres between them. This gives accurate positioning of the blank and therefore accurate positioning on the core tool and accurate positioning of the blank in the closed tool relative to the injection channels which define the seam channels for the completed container. The depth laterally of the cam faces has been exaggerated for illustration.

In an alternative blank centering arrangement, one or both guide rails could be hinged at their lower regions. The rails would be rotated to provide converging rail bottoms for free fall to any suitable stop pins and then the rails would be relatively pivoted to bring the bottoms to a spacing slightly less than the free edge widths with consequent slight bowing but accurate positioning relative to the core tool. Instead of pivoting, lateral displacement of one or both rails by solenoids could be adopted. In FIG. 6 rather than movement of the rails being adopted, the rails support

solenoids

12d, 13d which, upon actuation, will project inwardly of the rail bottoms to engage the edges of the blank adjacent the free edges to provide accurate positioning.

Referring again to FIG. 5, it will be seen that the wall of the guide rail channels remote from the cavity tool has been cut away at 122, 13e. When the base panel is advanced by the core tool, the side panels hinge relative to the base panel. If the edges of the side panel adjacent the free edges of the blank lie in continuous channels in the rails they cannot respond naturally to this hinging position but are bowed outwardly relative to the plane of the panel. To avoid this distortion and allow the side pannels to maintain their natural generally linear configuration at the side edges, the wall of each rail channel remote from the cavity tool is cut away. Thereby the corners of the side panels adjacent the free edges are able to spring out toward the core support plate 11 (FIG. 1) which is the natural movement of those corners during the hinging movement of the panels relative to the base panel.

In an alternative arrangement for centering the blank relative to the core tool, the leading face of the core may be provided with one or more projections and the blank base panel with one or more apertures; the projections being withdrawable at the closed condition of the tool and the apertures being closed by injected material during seaming.

With the tools in the closed condition, a suitable synthetic plastics material is injected, preferably through the base tool and its channel defined by the base tool and/or the split tool halves, which channels are located in the regions where the edges of the blank are juxtaposed in folding the blank and are thereupon free edges of the same panels to form the lip.

Where a cavity tool is used having a single impression or impressions one above another, it would be possible to displace the guide rails laterally outwardly to allow the tools to close; However, for a muIti-impression tool such as a horizontal row of three impressions, the centre rails cannot conveniently be displaced laterally and axial movement is preferred. In the case of such sideby-side impressions it may be desirable to keep the impressions as close as possible. To this end, the or each guide rail between adjacent impressions is preferably common to both impressions and is shaped so that the panels will overlap. Rails for a two impression tool are shown in FIG. 6, the central rail having a channel A serving the blank a of one impression and channel B the blank of the adjacent impression.

Referring now to FIGS. 8 to 13 the tool shown is a three impression tool. The tool includes a core support plate 111 which carries three core tools 110a, 110b, 110e, four

blank guide rails

112, 112, 113, 113, a split female tool having two

halves

114, 115, which define three

cavities

114a,114b, 1140, and three

base tools

116a, 116b, 1160.

Each base tool is carried in a phase plate 117 which will receive a hot runner nozzle, which will feed individual injection nozzles such as shown at 117a in FIG. 10. Base plate 1117 defines a cavity 118 which is generally a flat based Vsection channel running right across the face of plate 117. Slidable along

divergent walls

119, 120 of the cavity 118 are the

halves

114, 115, of the split female tool which are wedge shape in vertical section. Movement of the female tool halves inwardly of the cavity 118 from the open position, shown in broken lines for tool half 114 in FIG. 10, will bring

opposed faces

114a, 115a into abutting relationship and abut the end faces 114b, 115b against the base of the cavity. Bearing pads 1186 are secured to the diverging faces of the cavity 118. Each female tool half has a pair of channels 121 (FIG. 13) in each of which engages a guide pin 122 set in the base plate 117 and is biased away from the base plate by a pair of springs 123 each received in a recess in the female tool half and the base plate respectively. A pair of biased stop pins 126 for each female tool half are set in the base plate to provide bias urging the female tool halves outwardly of cavity 118, thereby to break any wedging of the tool halves which may occur as they are driven into the cavity. Dowels 118)) in the base plate 117 are received in pas sages 118C in the split tool halves to assist in guiding those halves.

The female tool halves, in the open position, lie between and spaced from the base tools and the four blank guide rails. The four rails have their opposed faces recessed to form the guide channels, are interconnected by support bars 126 which carry guide rods 127 received in blocks 128 on the base plate. The rails are biased away from the base plate by springs 129, sup ported by rods 129a received in recesses 12% of the base plate.

Referring to FIG. 9, the guide rails have adjustable blank stops 112', cuts out 113e and guide blocks 113]" which latter assist in folding the wings relative to the side panels.

Above the guide rails is a magazine M in which are three parallel packs of blanks P (one pack is shown) gravity biased down rails P, whichi engage each blank in the recesses on either side of the base panel, by a truck P" to bring the leading blank P against stops N at a gate 0. A vacuum plate T for each pack is movable by a ram R to pull the leading blank from each rack through its gate and release it to fall down a ram G blank guide channels V.

Each core tool includes at least one vacuum passage 135 (FIG. 12) opening at the forward face of the core tool and coupled to a manifold 135a in support plate 111 from the open condition, in which the leading face of the core tool is to that side of the plane of the associated guide channels remote from the base tool, toward the closed condition.

The vacuum passage serves, as each core tool is advanced, to engage the end wall panel of a blank when resting on a stop 112 in the associated pair of guide channels and to accurately hold that blank by vacuum as the advance of the core tool continues. With the blank accurately positioned in front of the core tool, the core tool carries it forward toward the base tool.

The core tool support plate 111 carries a stripper plate extending across the guide rails and plate 140 carries three stripper rings 141 each of which surrounds a core tool. Each ring 141 is dimensioned to pass between the associated pair of guide rails. As the tool closure progresses the stripper ring 141 engages the rear faces of the split tool halves and the stripper plate engages the guide rails so that the split tool halves close on to the cores under the action of the rings and the guide rails give under action of the stripper plate, their rods 127 riding in blocks 128. The tools when in the closed position define a cavity which is the shape of the walls, base, seams and lip of the final container. The moulding cavity is completely within the limits defined by the base tool and a plane intersecting the core tool forward of the stripper ring which latter plays no part in defining the moulding cavity. Thereby the wing free end edges, and in particular the corners W (FIG. 1) are clear of the stripper ring as they describe their arcs in the swinging of the side wall panels towards one another. The positioning of each moulding cavity forward of the rear end of the core tool results also in the edge 143 of the mouth of each cavity can be radiused to prevent any marking or scratching of a side panel as it slides over that edge during insertion. Also it enables the stripper ring to make an easy fit around the root of the core tool since no sealing function is carried out where the ring meets the core. Furthermore the forward face of the ring can be lubricated for the sliding motion of that face on the rear faces of the split tool halves, those faces being out of the path of the blank now that the blank is well forward of the stripper ring. Finally the outer surface of the container lip may be radiused, there being no abutting sealing edges defining the outer surface of the lip channel. The blank is trapped in the cavity in its final shape and proper position. By completing the advance of the blank relative to the split tool halves before they advance, no sliding of the blank side wall panels occurs over the surfaces of the split tool halves other than when those halves are well clear of the tool. Thereby the blank is not subjected to severe tension and shear forces due to frictron.

With the tools closed the thermoplastic material is injected from each nozzle 117a into a channel 137 extending across the base tool and across what will be the underface of the end wall panel. The material runs along the channel to a base peripheral channel 138, runs thereabout, along rib channels 139 (FIG. 12) and around a U-section lip channel 142 to complete the container. When the injected material is sufficiently hard the core tool withdraws followed by the rearwardly biased halves 1 14, 115. The parting of those halves releases the U-section lip.

The support plate 111 carries dowels 144 (FIG. 10) which engage recesses 145 in the base plate for aligning the tools. The stripper plate rides on rods 146 on the support plate coupled to the support plate by tension springs (not shown). In the opening movement the stripper plate is withdrawn by the support plate and is arrested by stops, not shown, forward of the rear limit of travel of the support plate by a distance sufficient for the stripper rings to drive the containers off the core tools.

While in the foregoing reference has been made to side wall panels and an end wall panel, it is to be understood that the three panels may be any three adjacent panels in an article.

Also whilst an arrangement has been shown in which vacuum is applied at the leading face of a core tool, it may be desirable in certain cases to provide at the leading face a retractable vacuum head which is in advance of the leading face. Thereby a blank end panel can be positioned on a base tool before the split halves close. Such a retractable head V is shown in broken lines in FIG. 12.

What I claim is:

1. Apparatus for producing a composite container from a blank comprising an end wall panel and side wall panels each of which projects from the end wall panel, the apparatus comprising a cavity tool having a cavity therein including side walls, a core tool movable relative to the cavity tool between an open and a closed condition, the cavity tool comprising cavity tool parts themselves slidably movable along said side walls between an open condition and a closed condition in the latter of which and with the core tool and the cavity tool in the closed condition a cavity is defined which corresponds to the shape of the container to be produced, a blank guide for receiving a blank and positioning the blank in the open condition of the core tool and the cavity tool between those tools and spaced therefrom and with the end wall panel in the path of relative movement of the core tool, relative movement of the core tool and the cavity tool in the closing direction, with a blank positioned by the guide therebetween, being operative to drive the end wall panel of the blank relative to the side wall panels and to the guide toward the cavity tool and to cause the core tool to move the cavity tool parts towards their closed condition, means being provided to inject material into vacant parts of the cavity defined by the core tool and the cavity tool in the closed condition to seam edges of the blank juxtaposed by relative movement of the core tool and cavity tool during relative closing movement.

2. Apparatus according to claim 1, in which the core tool completes relative movement of a blank along the line of relative movement of the core tool and the cavity tool before the cavity tool parts begin their relative movement toward one another to their closed condi tion.

3. Apparatus according to claim 2, in which the cavity tool includes a base having surfaces which diverge toward the core tool, the cavity tool parts being slidable along the diverging surfaces.

4. Apparatus according to claim 1, in which the guide comprises a pair of rails displaceable in the direction of relative movement of the core tool and the cavity tool. 5. Apparatus according to claim 4, in which the core tool includes stripper means movable relative to the core tool in the direction of relative movement of the core tool and the cavity tool which stripper means engage the cavity tool parts as the core tool and cavity tool move toward the closed condition to drive the cavity tool parts toward the closed condition of those parts.

6. Apparatus according to claim 5, in which the stripper means include a stripper plate carrying a stripper ring, the plate engaging the rails during the relative closing movement of the core tool and the cavity tool.

7. Apparatus according to claim 6 in which the stripper plate is movable relative to and is biased toward a support plate of the core tool, stop means being provided in the path of the stripper plate in the direction of relative opening of the core tool and cavity tool to arrest the stripper plate before the core tool reaches its opening limit position whereby the stripper plate is advanced relative to the core tool to strip a container therefrom.

8. Apparatus according to claim 7 in which the stripper means are located at or rearward of the extreme locus of the blank free edges as the blank folds on to the core.

9. Apparatus according to claim 1 in which the guide comprises a pair of rails which have opposed surfaces which are stepped to provide first larger spacing therebetween in the direction of blank gravity feed to position a blank end wall panel opposite the core tool, a second reduced spacing in that part of the rail lengths occupied by the blank when so positioned, and a third further reduced spacing.

10. Apparatus according to claim 1 in which the guide comprises a pair of rails recessed on the opposed surfaces, the wall of each recess remote from the cavity tool parts being interrupted to allow a portion of blank to pass out of the recess as the end wall panel is advanced relative to the guide by the core tool.

Claims

2. Apparatus according to claim 1, in which the core tool completes relative movement of a blank along the line of relative movement of the core tool and the cavity tool before the cavity tool parts begin their relative movement toward one another to their closed condition.

4. Apparatus according to claim 1, in which the guide comprises a pair of rails displaceable in the direction of relative movement of the core tool and the cavity tool.

5. Apparatus according to claim 4, in which the core tool includes stripper means movable relative to the core tool in the direction of relative movement of the core tool and the cavity tool which stripper means engage the cavity tool parts as the core tool and cavity tool move toward the closed condition to drive the cavity tool parts toward the closed condition of those parts.