HK1130731B - Capsule for preparing a beverage with a sealing member for water tightness attached thereto and method of producing the same - Google Patents

Description

Capsule for preparing a beverage with a watertight seal and method for manufacturing the same

Technical Field

The present invention relates generally to capsules for containing beverage ingredients, beverage production systems for use in connection with such capsules and methods for manufacturing such capsules.

Background

The background of the invention is the field of capsules containing beverage ingredients (e.g. ground coffee, milk powder) or other edible ingredients (e.g. dehydrated soup). By allowing these ingredients to interact with the liquid, a beverage or other food can be produced. The interaction may be a process such as extraction, brewing or dissolution. Such capsules are particularly suitable for containing ground coffee for producing a coffee beverage by letting pressurized hot water into the capsule and draining the coffee beverage from the capsule.

Systems and methods for obtaining an edible liquid from ｃA substance containing capsule are known, for example, from EP- ｃA-512470.

The general principle of this extraction method can be summarized as follows:

-inserting the initially closed capsule into a capsule holder means closing the capsule in a watertight manner;

-water injection means of the machine inject water into the capsule;

the water, when traversing the interior of the capsule, interacts with the ingredients contained within the capsule and then leaves said capsule through at least one opening/perforation formed in the second wall.

The ingredients in the capsule form a "bottleneck" of the flow path of the water and thus create a pressure drop between the upstream and downstream sides of the liquid flow through the capsule, which pressure drop may even increase during the interaction between the liquid and the ingredients, e.g. due to swelling of the ingredients. Accordingly, it must be ensured that the water flow actually passes only through the interior of the capsule, and that no water can flow from the water injector into the interspace between the annular enclosing member and the exterior of the capsule and to the drainage holes of the device. In other words, any water flow to the outside of the capsule must be prevented by the sealing engagement between the annular enclosing member of the holder means and the capsule and in the flow path between the water injector and the beverage drainage hole.

Such a sealing engagement may be achieved, at least to some extent, by a clamping engagement between the capsule holder means (i.e. the annular enclosing member and the capsule holder) and the flange-like rim of the intermediate body.

In case the sealing engagement does not work properly and water flows outside the capsule, a pressure sufficient to tear the tear face will not build up inside the capsule or the pressure will not tear the tear face completely, resulting in poor extraction of the substance. In this case, water will drain from the beverage production device without having interacted or fully interacted under sufficient pressure conditions with the ingredients contained in the capsule.

An improvement can be envisaged in which the inner wall of the annular member is coated with a rubber-elastic material to further improve the sealing engagement. In other words, according to the method, the sealing engagement may be ensured by a structure fixed or attached to the beverage production device. A drawback of this improvement is that, after the use of a large number of capsules, the stationary sealing means are subject to wear, so that the quality of the produced beverage is deteriorated by the passage of water through the seal which is no longer completely effective. Also, the sealing device with the sticking organic residues becomes dirty, which is very unhygienic and can affect the sealing and pressure conditions during extraction.

Any "leak" outside the capsule will reduce the pressure build-up inside the capsule. On the other hand, it is well known that sufficient extraction pressure is a key factor in the quality of espresso coffee.

European co-pending patent application No.04025320.5 entitled "Capsule with sealing means" is intended to improve the sealing engagement of such a beverage production system arranged between the liquid inlet and the beverage discharge side. The object of the invention is to transfer a sealingly engaged resilient member from a beverage production device to a capsule. The advantage of this is that any resilient sealing member is only used once (i.e. only with the associated capsule), thereby ensuring that the seal functions correctly and that no hygienic problems arise at the sealing member.

Disclosure of Invention

The present invention aims at making further improvements to the european co-pending patent application No.04025320.5, with the aim of improving the sealing conditions between the capsule and the sealing member so as to ensure watertightness during brewing. In practice, it is important to avoid any possible liquid leakage between the sealing member and the rest of the capsule, in particular due to the good bond created between the two.

In addition, it is also important to incorporate the sealing member into the capsule using a highly reliable method with a minimum reject rate and cost-effective, which can be implemented industrially on a large scale.

This object is achieved by the features of the independent claims. The dependent claims develop further the central idea of the invention.

For this purpose, the method of the invention is used for providing a sealing member on the body of a capsule containing beverage ingredients, said capsule being designed to be inserted into a beverage production device, wherein a liquid under pressure enters the capsule to interact with the ingredients in the capsule and to drain a beverage from the capsule,

characterised in that the method comprises providing a body and injecting at least one sealing material by injection moulding onto at least a portion of an outer surface of the body to mould a sealing member sealingly attached to the body.

More particularly, forming the seal by injecting a sealing material (or sealant) has many advantages. First, the adhesion of the seal is greatly improved compared to attaching a prefabricated seal. Thus, it is possible to prevent liquid leakage between the sealing member and the capsule body and to better guarantee and maintain the extraction conditions (better reproducibility of the brewing conditions) between the capsule and the capsule. Since the sealing member is attached more firmly as part of the capsule, the risk of separation or detachment of the sealing member is less suitable for use in a beverage brewing machine for receiving capsules having a sealing member and thereby reducing the risk of malfunction.

Furthermore, this increases the chances of producing capsule bodies with simpler or more varied shapes. The method is faster, more cost effective than attaching a seal by mechanical, welding and/or adhesive means, and can be implemented in an efficient manner, at high throughput and on a large industrial scale.

Preferably, the sealing material is made of a material different from the material of the body. More preferably, the sealing material is softer than the material of the body.

In a preferred embodiment, the body is formed with a flange-like rim and the injecting step comprises injecting the sealing member over the flange-like rim. In the flange-like rim area, the capsule is gripped by an enclosing member of the beverage production device (e.g. a bell member and a capsule holder sealingly enclosing the capsule). The injected seal is of a material softer than the material at the flange-like rim of the body and the seal can be compressed to compensate for irregularities, gaps or voids etc. to maintain water tightness under brewing pressure in the capsule shell.

The flange-like rim may further comprise an anchoring/fixing portion and a supporting portion. The anchor is arranged such that during injection, material of the sealing member may flow in the anchor in order to improve the connection between the sealing member and the body.

The anchoring portion may be constituted by a partially curled portion. The curl may include an opening, such as an annular opening, in which the plastic flows during injection. The crimp may be formed during the deep drawing operation of the body before injecting the sealing member or in a separate flange-like rim forming operation after deep drawing the cavity of the capsule body. The operation of injecting the seal is preferably high pressure plastic injection. The capsule body is clamped internally (i.e. on the cavity side) and externally (i.e. on the outside of the side walls of the body) by an injection mould, and said mould defines an injection shell for delimiting the volume to be filled for the sealing material. The sealing material may be injected at a pressure in excess of 500 bar, preferably between 500 and 2000 bar, more preferably between 800 and 1500 bar. The injection time is very short and usually does not exceed one second. After injection the sealing material is allowed to cool to solidify over the course of a few seconds, typically between 3 and 8 seconds.

The material of the seal should be selected from thermoplastic elastomers that are resilient, heat and pressure resistant and injectable. Preferably, the thermoplastic material is typically a thermoplastic elastomer ("TPE"). More preferably, the TPE is a polypropylene-based elastomer.

As mentioned above, in an initial manufacturing step, the capsule body can be preformed by deep drawing a metal or metal-plastic sheet. The capsule body can be deep drawn in one step or in successive steps to form a final main open cavity that can be filled with food ingredients. The flange-like rim, the anchoring means, in particular the curled end of the rim or other important functional shape may be formed during the deep drawing operation.

In addition, it is possible to locally deform at least one portion of the body side wall in order to further form anchoring means for the seal, in particular in an annular portion of the seal extending along the body side wall. The local deformation may be formed in the side wall of the body so as to cause the body wall to produce, for example, one or more arcuate projections that rise into the material of the seal. The local deformation may occur during injection or cooling of the seal. In another subsequent step, the body is filled with food ingredients, such as roast and ground coffee.

The capsule body may comprise aluminium. The body may be a single layer of aluminium or a multilayer of plastic and aluminium, for example polypropylene and aluminium.

The invention also relates to the production of a capsule containing beverage ingredients designed for insertion in a beverage production device, i.e. between capsule enclosing members, wherein a liquid under pressure enters the capsule to interact with the ingredients in the capsule and to drain a beverage from the capsule. The capsule comprises a body with a sealing member attached thereto. The sealing member is used to provide water tightness between the capsule and at least one pressing surface of the production device, i.e. one of the enclosing members of the device. The method includes providing a body, filling the body with a food ingredient and hermetically closing the body. The method also includes injecting at least one sealing material onto at least a portion of the outer surface of the body by injection molding to form a seal sealingly attached to the body.

In a subsequent step after the food ingredient filling step, a membrane is welded along a portion of the outer surface of the flange-like rim in order to close the capsule. The sealing film may also be aluminum or a laminate of plastic and aluminum.

The invention also relates to a specific injection pattern for injecting sealing material on the surface of the capsule body produced according to the method of the invention.

The layout comprises:

a first injection mould part comprising at least a first and a second injection side for receiving a plurality of capsule bodies,

-at least a second injection-moulding part for closing said first injection-moulding part and engaging with said plurality of capsule bodies;

-at least a first body changing device for changing the capsule body in one of the first or second injection side of the first injection mould part while injection moulding of the sealing material is performed on the capsule body of at least the other injection side of the first injection mould part,

wherein the first injection molded part and at least the second injection molded part are movable relative to each other such that the second injection molded part selectively closes the first and second sides of the first injection molded part.

Thus, according to this particular layout, the injection moulding of the capsule bodies can be achieved in a high-throughput and automated manner.

More particularly, the first and second side portions of the first injection-moulding part comprise a set of cavities for receiving the capsule bodies, while the second injection-moulding part comprises a set of mandrels for engaging the capsule bodies when the injection-moulding parts are closed.

The other dependent claims develop further this particular layout for implementing the method of the invention.

Drawings

Other advantages, features and objects of the present invention will become apparent to those skilled in the art from the following detailed description of embodiments of the invention, when read in conjunction with the accompanying drawings.

Fig. 1 shows a first embodiment of the capsule system of the invention, wherein the capsule is placed on a capsule holder, but has not yet reached its closed position in the beverage production device,

figure 2 shows an enlarged view of figure 1,

fig. 3 shows a first embodiment, wherein the capsule reaches its closed position between the capsule enclosing member (i.e. the bell member and the capsule holder),

figures 4 and 5 schematically show the injection operation of the sealing member on the capsule body,

fig. 6 to 10 show details of the male injection mould, which holds the capsule body and provides the deformation 'in situ' during the injection operation,

figure 6 shows that the capsule body does not have a male die placed on it,

figure 7 shows the male mold on which the capsule body is placed after injection of the sealing member,

fig. 8 shows the male mold on which the capsule body is placed, but with the sealing member removed in order to show the local deformations formed on the body by the mold,

figure 9 shows a cross-section of the male die without the capsule body,

figure 10 shows a cross-sectional view of a detail of the male mold on which the capsule body is placed and the sealing member is injected,

figures 11 to 13 show injection device layouts at the manufacturing site with high throughput of parts for injecting capsules,

figure 14 is a flow chart illustrating the steps of an embodiment of a method according to the present invention,

fig. 15 is a flow chart showing the steps of a variant of the method according to the invention.

Detailed Description

It should be noted that the invention will be explained hereinafter with reference to a specific design of the capsule, i.e. a design in which the capsule comprises a cup-shaped base body and a closing foil member. However, it will be appreciated that other designs of the capsule are possible, for example a capsule having the form of a lenticular lens, wherein two substantially matching and opposing walls (e.g. foils) are sealed at, for example, an annular edge. A capsule according to the invention typically comprises at least two opposing wall members (surfaces) which are interconnected at their respective edges to form a sealed flange-like rim area, thereby enclosing a sealed interior.

This embodiment shows a capsule holder 13 with relief elements 12 for tearing and piercing the foil member 5 of the cup-shaped base body 4 closing the capsule 1. The tearing of the foil member 5 is performed immediately when the pressure inside the capsule exceeds a threshold value. It should be noted that the relief elements may have any protruding shape capable of causing a controlled tearing of the foil member. By way of example only, pyramidal, needle, ridged, columnar, elongated rib-like shapes may be mentioned. The relief element may also be a single piece.

Fig. 1 shows a state in which such a capsule has been placed on a capsule holder 13, wherein the foil member 5 rests on the relief elements 12 of the capsule holder 13 and said cup-shaped base body 4 of the capsule 1 has been partly surrounded by the circumferential wall 25 of the enclosing member 9 of the beverage production device. The shown enclosing member has the shape of a bell. Other shapes are possible, wherein the design of the inner contour (recess) of the enclosing member is typically adapted to substantially match the contour of the capsule 1.

Thus, the capsule holder 13 (also an enclosing member) and the enclosing member 9 can selectively enclose the capsule enclosing space 22 when being transferred from the open position to the capsule enclosing position.

It should be noted that the foil member 5 shown is not completely flat due to the overpressure defined within the capsule, which is generated by introducing, for example, a protective gas and a delayed degassing of the food ingredients after sealing, such as carbon dioxide from coffee, during the manufacture of the filled capsule.

The enclosing (bell) member 9 further comprises an annular pressing surface 18 and a water inlet 20 for supplying a liquid, such as pressurized hot water, to a water injection system 14 which is releasably mounted, e.g. screwed, on the bell member 9.

The water injection system may comprise one or more perforation elements (blades, pins, etc.) 24 designed to create one or more openings in the top wall 17 of the capsule 1 when the capsule holder 13 and the bell member 9 are brought close to each other, e.g. by a manually operated or automated mechanism. The channel 19 traverses the injection system and opens into the enclosing space 22 of the enclosing member 9 so that water can be supplied to the interior of the capsule 1 once the perforating elements 24 have penetrated into the interior of the capsule 1.

The capsule 1 comprises said top wall 17, a side wall 7 and a flange-like rim 6, wherein the foil member 5 is sealed to said flange-like rim 6 for sealingly closing the cup-like base body 4 of the capsule 1. Also other designs of the capsule are possible as long as the capsule can be sealed and contain the ingredients.

According to the invention, the outer surface of the capsule 1 has a special watertight seal 8 (made of sealing material), hereinafter referred to as "seal". The seal 8 may be compressed and more preferably is resilient.

The material of the seal may be an injectable thermoplastic elastomer.

As shown more clearly in fig. 2, the capsule of the invention comprises a flange-like rim 6 having a support 60 for the sealing member and a partially curled end 61 constituting an anchoring portion of the sealing member. The support 60 merges with the side wall 7 of the body 4 at an angle (i.e. slightly more than 90 degrees when the body has the form of a truncated cone). The flange-like rim and the bottom surface 70 of the side wall receive the annular seal 8. In order to attach the sealing member to the flange-like rim in a reliable manner, the sealing member extends towards the partial curl 61 via a connecting portion 80 injected into the partial curl 61 of the rim. The curled end forms a "hook" for sealing material, thereby increasing the connectivity and water tightness between the seal and the rim. Outside the partial curl 61, the seal 8 extends along the bearing portion 60 of the flange-like rim by means of a sealing portion 81, which sealing portion 81 can extend by means of a ring-like portion 82 resting against the bottom surface 70 of the side wall 7 of the body. The sealing portion 81 and the ring portion 82 may form surfaces of different slopes or may merge in a single continuous concave or flat sloping surface. The sealing member 8 is selected to have a wedge-shaped profile so as to provide a sufficient mass of sealing material to compensate for irregularities, tolerances, voids or other gaps between the capsule and the enclosing or bell member, for example due to wear of mechanical surfaces. Since a watertight seal can also be obtained dynamically, i.e. by the effect of the pressurized water acting on the seal, the shape, size and overall mass of the seal should be sufficiently large to deform so as to "flow" elastically and fill the remaining opening correctly when the pressure builds up during brewing.

Fig. 3 shows the state in which the enclosing member 9 and the capsule holder 13 are in pressure-tight engagement at the rim, and the pyramid-shaped relief elements 12 of the capsule holder 13 create openings in the foil member 5 of the capsule 1 as water enters the interior of the capsule and builds up pressure therein. When the capsule is inserted, the blade element 24 of the water injector 14 has produced the perforations 16 in the top wall 17 of the capsule 1. When a sufficient fluid pressure is established inside the capsule, the beverage produced from the ingredients contained in the capsule can be expelled from the gaps or perforations created by tearing of the foil member 5 by the relief elements 12.

In a first step of the method (not shown), a body 4 of the capsule is produced. The body can be manufactured as a preform with a flange-like rim 6 which is kept open for injection of the material of the sealing member in a subsequent injection step. The body 4 may be preformed by deep drawing a sheet metal material or a composite layer assembly comprising metal, such as aluminium and plastic (e.g. polypropylene), and finally gluing and/or painting. Depending on the complexity of the body shape and the depth of the cavity, the sheet material may be deep drawn in more than a single step. Also, the cavity of the body and the flange-like rim may be formed in the same operation or in separate operations.

Figures 4 and 5 illustrate the operation of injecting the sealing member 8 on the preformed body 7. Thus, the body may be placed between injection mold assemblies 30. The mould assembly generally comprises two mould parts, a female part 31 and a male part 32, which are tightly assembled around the capsule body and leave an injection chamber 35 for injecting sealing material therein to form the sealing member. The female mould part 31 surrounds the outer side wall 7 and the top wall 17 of the body and typically also defines a volume 35 for injection of the seal over the flange-like rim 6 and further extends to a parting line 34 located substantially at the end of the partial curl 61 of the rim, for example, thereby enabling easy removal of the body from the mould after injection. Male mold part 32 is inserted into the cavity of the body and mates with the outer shape of the flange-like rim (e.g., the lower surface of the rim) up to parting line 34.

Advantageously, the die assembly 30 extends along the entire side 7 of the body and exerts a large mechanical pressure on the side wall 7. This has a dual advantage.

First of all, the injection generates a short time high pressure, so that a pressure-resistant injection sealing arrangement is necessarily obtained, in particular at the junction line 34 between the outer side wall of the body and the highest point of the sealing member.

Secondly, the pressure may also smooth the outer surface 73 of the side wall of the body. Since the body is generally frusto-shaped, previous deep drawing operations tend to produce wrinkles in the surface of the side wall. The mechanical pressure of the male and female dies directly against the entire opposite surface of the side wall 7 therefore smoothes the folds and eliminates or at least significantly reduces such visual defects.

The injection is performed through at least one small injection gate 36. The opening of the door at the entrance to the injection chamber may be about 0.5-1 mm. The injection is carried out at high pressure, i.e. 700 to 1500 bar on average, in the course of less than 1.01 seconds, usually 0.01 seconds. The plastic is injected at a temperature above the glass transition temperature. The preferred thermoplastic elastomer is TPE. The resulting seal 8 is allowed to cool for at least a few seconds, typically 5-10 seconds, and then the mold assembly is reopened and the body is withdrawn. Cooling may be assisted with a coolant circulating in the cooling circuit of the mold assembly to reduce the hardening period of the seal.

Figures 6 to 10 show in detail the male injection mould device 40 according to one possible embodiment. The male die means 40 may be mounted in a sealed manner on a frame 41. It comprises a spindle 42 with an end substantially matching the internal cavity of the body of the capsule, as shown in figure 8. The mandrel is internally provided with a movable eccentric punching assembly 43, as shown in figures 9 and 10. The eccentric assembly comprises two punch members 44, 45 slidably mounted along the radially oriented slots 37, 38 of the mandrel (fig. 9). The punch members 44, 45 are actuated to extend/retract through the slots by a longitudinal pusher 46 which moves back and forth along the longitudinal axis of the mandrel. The central pusher has ramp portions 47, 48 which allow the punch members 44, 45 to slide in opposite radial directions along the grooves.

As shown in fig. 10, when the central pusher is pushed upwards, the punch members 44, 45 move radially against the side wall 7 of the body 4 and thus deform the side wall of the capsule body outwards along the arc-shaped recesses 71, 72 (fig. 8) projecting inside the sealing member 8 (fig. 10). The recess may be formed at any time after insertion of the capsule body on the mandrel and before the injected material hardens. Preferably, the depression is formed after injection, for example, 0.5 to 1 second after stopping injection.

The recesses 71, 72 improve the anchoring of the seal at a bottom region on the side wall, which is critical and where the seal tends to detach from the body. Thus, by preventing the risk of leakage at the gap between the sealing member and the body, a better water tight seal is also provided to some extent.

It should be noted that the depressions may be formed in a variety of ways as will occur to those of skill in the art, and that the present invention is directed to one possible way of industry for exemplary purposes only. The depressions may also have different forms, such as pins, ridges, etc.

Fig. 11-14 show one possible layout of an injection station operating an injection cycle at high throughput. The general principles of which are explained in detail below.

Fig. 11 shows an overall injection layout that can handle two sets of injection assemblies running simultaneously on opposite sides. The principle is based on a cubic injection female mold part 60 comprising four injection mold sides 61, 62, 63, 64 and being rotatable 90 degrees along a central axis 65 to move the sides in a 90 degree progressive path. Each female side comprises a set of injection mould cavities 600 for the respective insertion of the capsule bodies therein. The cavities are generally distributed on the side of the mould according to a predetermined pattern, preferably along a certain number of rows and columns, for example in a square pattern, 7 rows by 7 columns thus resulting in a total of 49 individual injection points. The pattern and the number of rows and columns in the pattern may vary depending on the desired yield.

The cubic injection cavity block 60 is associated with two male molds 66, 67 facing opposite sides 61, 63 of the cubic cavity block part. The male dies 66, 67 are reciprocally movable relative to the cubic mold 60 so as to be able to open and close the cavity sides of the cubic injection mold. The male moulds 66, 67 also comprise convex mandrels 42, the number and distribution of which matches the number and distribution of the injection sides.

Facing the other two opposite sides 62, 63 of the cubic mould, in a direction orthogonal to the "injection direction I" (i.e. the direction in which the mould assembly closes simultaneously on the cubic mould), there are mounted storage and transport means 68, 69 for automatically loading/unloading the bodies in the cavities 600 of said sides. These storage and transport means may comprise loading areas 680, 681 arranged to comprise "bare" capsule bodies (bodies without injected sealing members) in a square pattern and body storage areas 682, 683 for receiving "sealed" capsule bodies (i.e. bodies with injected sealing members thereon). In the middle, multidirectional robots 684, 685 are arranged, which are configured to, respectively: a) unloading simultaneously (at once) the sealing bodies of the given pattern from the full injection side, b) transporting the sealing bodies of the given pattern to the body storage area 682, 683, c) retrieving simultaneously the bare capsule bodies of the given pattern from the loading area 680, 681, and, d) transporting and placing these bare capsule bodies in cavities that have been moved to the injection side facing the storage and transport means.

The multi-directional robots 684, 685 may include respective suction devices, such as vacuum-assisted suction devices, to transport and release (all) of the body simultaneously.

Fig. 12 shows the injection cycle for two sets of patterns J1, J2 simultaneous injections. While these sides 61, 63 inject, other loading/unloading operations may be performed simultaneously. In step a, the robot removes the sealed body from the filled sides 62, 63. Then in step B the robot transports and unloads the sealed body in the unloading zone 682, 683. In step C, the robot takes the new waiting pattern of bare capsule bodies (e.g. 49 bodies arranged in a 7 × 7 square pattern) from the body loading areas 680, 681. Then in step D shown in fig. 13, the robot transports and loads the obtained bare capsule bodies in the empty injection sides 62, 64 of the cubic mold part 60. Steps a-D may be performed while the other two sets of bodies in the two adjacent sides 61, 63 are being injected with the sealing member. Thus, a higher throughput can be obtained, since almost every about 10 seconds too large, two sets of 49 (and therefore 98 in total) bodies can be injected with the sealing member.

The injection layout of figures 11 to 13 can be simplified so as to form only one loading/unloading station with only one male injection mould.

As shown in fig. 14, the method comprises one or more steps 100 of deep drawing the capsule body, 110 of injection molding of the sealing member (or "ring"). In the next step 120 the body is filled with food ingredients and finally in step 130 the membrane 5 is welded, for example by thermal or ultrasonic welding, on the outer surface of the support portion 60 of the flange-like rim. Additional steps may be envisaged at any suitable time during the production process, such as positioning and bonding the filter inside the body and/or the membrane 5 before and after deep drawing of the body.

The invention includes other possible variations. For example, the seal may be made of two or more materials of different hardness. For example, an inner layer of a first material may be injected over the body first. An outer layer of a second material, softer than the material of the inner layer, may then be overmolded onto the inner layer. The inner layer may improve the adhesion of the second material. The outer layer material may be softer in order to reduce the closing force required to close the enclosing member of the beverage production device acting on the capsule.

In another possible variant, shown in figure 15, the capsule body can be made of plastic material. The body is also preferably injection molded. The body and the sealing member can be co-injection molded (step 140). The young's modulus of the body plastic may be higher than that of the seal, but the two materials should be compatible so as to adhere to each other. An example of a suitable material for the body and the sealing member is TPE. The body may also be an injection-moulded laminate comprising one or more gas-barrier layers, such as EVOH (ethylene vinyl alcohol copolymer), sandwiched between inner and outer layers of TPE.

Claims (22)

1. A method of providing a sealing member on a body (4) of a capsule (1) containing beverage ingredients, the capsule being designed for insertion in a beverage production device, wherein a liquid under pressure enters the capsule for interacting with the ingredients in the capsule and draining a beverage from the capsule, the sealing member being geometrically arranged for sealing engagement with at least one cooperating pressing surface of the beverage production device,

characterized in that the method comprises providing a body (4) and injecting at least one sealing material by injection molding over at least a portion of the outer surface of the body (4) so as to mold a sealing member (8) sealingly attached to the body, said body (4) having a flange-like rim (6) and said injecting step comprising injecting said sealing member (8) over said flange-like rim (6).

2. Method according to claim 1, characterized in that the injected material for the sealing member (8) is different from the material forming the body.

3. Method according to claim 2, characterized in that the injected material for the sealing member (8) is softer than the material forming the body (4).

4. Method according to claim 2, wherein the flange-like rim (6) comprises an anchoring portion (61) and a support portion (60); wherein the injecting step comprises injecting the sealing member (8) in both the anchoring portion (61) and the support portion (60).

5. Method according to claim 4, characterized in that the anchoring portion is formed by a partially curled portion comprising an opening in which the injection material for the sealing member (8) flows during injection.

6. The method according to any of the preceding claims, wherein the injection is performed at a pressure of 500 to 2000 bar and during less than 1 second or 1 second.

7. Method according to claim 1, characterized in that after the injection is completed, the body (4) and its injected seal (8) are allowed to cool for a few seconds in the injection mould (31, 32).

8. The method of claim 1, wherein the injected material for the seal is a thermoplastic elastomer.

9. Method according to claim 1, characterized in that the capsule body (4) is preformed by deep drawing a metal or metal-plastic sheet.

10. Method according to claim 9, wherein the capsule body (4) comprises aluminium.

11. Method according to claim 9, characterized in that at least one local deformation (71, 72) of the body side wall (7) is brought about in order to form anchoring means for the seal (8).

12. Method according to claim 11, characterized in that the at least one local deformation (71, 72) occurs during injection or cooling of the injection molded seal (8).

13. The method of claim 11, wherein the at least one localized deformation is achieved by a deep drawing operation.

14. Method according to claim 1, characterized in that the body (4) is injection-molded.

15. Method according to claim 14, wherein the body (4) and the sealing member (8) are co-injection moulded.

16. A method as claimed in claim 1, characterized in that it comprises welding a membrane (5) to hermetically close said body (4).

17. Injection pattern for carrying out the method of providing a sealing member on a body (4) of a capsule (1) containing a beverage ingredient according to claim 1, comprising:

-a first injection-moulding part (60) comprising at least a first injection side (61, 63) and a second injection side (62, 64) for receiving a plurality of capsule bodies,

-at least a second injection-moulding part (66, 67) for closing said first injection-moulding part (60) and engaging with said plurality of capsule bodies;

-at least a first replacement device (68, 69) for replacing the body in one (62, 64) of the first or second injection sides of the first injection-moulded part (60) while injection-moulding of sealing material is performed on the body of at least the other injection side (61, 63) of the first injection-moulded part (60),

wherein the first injection mould part (60) and at least the second injection mould part (66, 67) are movable relative to each other in order to enable the second injection mould part (66, 67) to selectively close the first injection side (61, 63) and the second injection side (62, 64) of the first injection mould part.

18. Layout according to claim 17, characterized in that the first and second injection side of the first injection-molded part (60) comprise a set of cavities (600) for receiving capsule bodies, while the at least second injection-molded part (66, 67) comprises a set of mandrels (42) for engaging with capsule bodies when the injection-molded parts (60, 66, 67) are closed.

19. Layout according to claim 18,

the first injection-molded part (60) is a cubic mold (60) comprising four injection sides (61, 62, 63, 64) and configured for rotation in 90-degree steps,

the layout comprises:

two second injection-molded parts (66, 67) configured to selectively engage two of the four injection sides (61, 63) of the cubic mold (60) when the cubic mold is rotated to an injection position of two of the four injection sides (61-64), and

two replacement devices (68, 69) configured to replace the bodies of the other two injection sides (62, 64) not located in the injection molding position with respect to the second injection mold part (66, 67).

20. Layout according to claim 18 or 19, characterized in that the replacement means comprise automatic means (684, 685) for simultaneously replacing the bodies of the injection sides.

21. Layout according to claim 19, characterized in that the sets of cavities (600) and mandrels (42) are distributed according to a substantially square pattern.

22. Layout according to claim 21, characterized in that the substantially square pattern comprises at least 7 rows and 7 columns of cavities (600) and mandrels (42).