DE102017111348A1 - Method for producing a seal in or on a closure for a container, closure and device for producing a closure - Google Patents

Abstract

A method of manufacturing a gasket in or on a closure for a container characterized by the steps of: a) pre - metering a sealant containing a polymer, b) plastifying the premetered sealant by ultrasound, c) applying the premetered sealant to a sealing surface of the sealant Closure, wherein the step b) optionally before, after or simultaneously with step c) is performed.

Description

The present invention relates to a method of manufacturing a gasket in or on a closure for a container.

The container closures of the type relevant here are, for example, metal closures for glass containers, such as glass bottles or the like, which are provided on their inside with a seal. The seal is applied flat on an inner side of the closure, typically annular, so that it reliably seals the closure body against the edge of the container.

Are known seals that are made of a sealant containing a polymer. This polymer composition is introduced, for example, in an injection molding process in the closure. Such methods and corresponding devices are for example in US 2012/0171381 A1 and in US 2016/0318212 A1 shown. A method for producing an annular seal is further disclosed in US 2011/0100994 A1 disclosed.

US 2012/0171381 A1 and US 2016/0318212 A1 describe each method in which the annular seal of the injection molding tool is made with a central, in the tool die axially extending supply duct. Radial channels extend from this axial feed channel, from which the sealant exits and is sheared off by an outer punch. The seal can then optionally be completed by another punch.

In general, high production rates are necessary in the production of container closures. However, the use of an injection molding technique has proven problematic in this context. In this case, in the method described above, the gap between the central punch and the outer punch, which is movable thereon, repeatedly sticks to the narrow gaps between the moving parts of the spray head and to a build-up of dried sealant on the Outlet openings of the extrusion channels. This results in production interruptions, since the tools concerned have to be maintained or replaced. Temperature, pressure and flow rate of the sealant must be precisely controlled in this injection molding process, especially at the already mentioned high application rates, to keep the deviations of the predetermined amount of sealant low. This is problematic in the above-mentioned methods in that during the short time in which the outlet opening (s) is closed, a backlog and thus a standstill of the sealant forms in the channels, up to the continuously conveying extruder screw can go back. The resulting high-frequency pressure fluctuations can lead to uneven amounts of applied sealant, increase the wear of the extruder / plasticizers and / or require the use of additional devices that can compensate for these pressure fluctuations. The energy used in such injection molding processes to obtain pressure, temperature and viscosity of the sealant is also relatively high.

This in US 2011/0100994 A1 Although described method uses another technique in which the sealant is pressed into an annular channel. Here, however, other problems arise because the annular chamber for forming the seal can fill unevenly, that is, the seal is formed as a result uneven. Also, this method does not provide satisfactory results. Above all, the pre-metering / shearing of plasticized sealant and the transfer of this plasticized mass into the closure also cause unavoidable contamination of the tools, which leads to high maintenance costs and downtimes.

There is therefore a need for an improved method of manufacturing gaskets in container closures which works reliably even at high production rates and produces the gaskets in constant quality.

The object of the present invention is thus to provide such a method, as well as a corresponding device for producing a container closure, which overcomes the above problems.

The aforementioned objects are achieved according to the invention by a method having the features of claim 1, and by a device having the features of claim 18.

In the method according to the invention, the sealant is predosed and plasticized by means of ultrasound. For this plasticization, experience in the field of ultrasonic welding can be used, in which a welding head, a so-called sonotrode, which is in contact with the workpieces to be welded, is excited to ultrasonic vibrations, by which the workpiece or workpieces are fused in the weld zone.

In the method according to the invention, only a predosed part of the sealant becomes plasticized, ie, the plasticization takes place only when a designated for the formation of the seal part of the sealant is separated from a sealant mass supply. Both the dosage of the required sealant and their plasticization can then be carried out more targeted and with higher precision. The problems encountered in the injection molding process described above, such as a sticking of the tools, a backwater or the like, are thereby avoided.

It is also possible to carry out the plasticization of the pre-dosed sealant by means of ultrasound shortly before or during application to the sealing surface of the closure provided for this purpose. Compared to the injection molding method described above, the energy for obtaining pressure, temperature and viscosity of the sealant can be saved from the time of plasticizing until reaching the job site. In this case, in particular, the tool provided for application, such as, for example, an application stamp, which moves the pre-metered sealant against the sealing surface, can serve as sonotrode, that is to say for the contact transmission of the ultrasonic vibrations. The plasticization can thus take place, for example, after such an application stamp has taken over the predosed sealant and transported against the sealing surface, so even before the predosed sealant contacts the sealing surface, or at a time when the sealant has already been applied by the application tool on the sealing surface so she is in contact with this. Another possibility is to carry out the plasticization after the above-described application of the sealant to the sealing surface, ie, for example, when the application tool is already in a retraction movement. Then, the plasticization can take place in other ways, such as by transmitting the ultrasonic vibrations to the container itself, or by a separate sonotrode.

As described above, according to the invention, the plasticization of the predosed sealing compound can be carried out prior to its application to the sealing surface, or simultaneously with the application, or subsequently.

In the following preferred embodiments of the present invention will be described, as set forth in the subclaims, wherein the respective embodiments can be implemented separately from one another, but can also be combined with one another, as far as is technically possible and reasonable.

According to a preferred embodiment of the present invention, the sealing compound applied to the sealing surface is deformed under mechanical pressure. This can be done after completion of the application of the pre-metered sealant to the sealing surface, so for example by another tool such as a forming die, which gives the seal its final shape.

Further preferably, the sealant is still formed during application to the sealing surface under mechanical pressure. In particular, the applicator can be used for this purpose, which applies the predosed sealant to the sealing surface in the manner already described above. The applicator also has the function of a Umformstempels in this embodiment.

According to a further preferred embodiment of the invention, the deformation is carried out in the at least partially plasticized state of the sealant.

According to a further preferred embodiment of the invention, at least the sealing surface of the closure is preheated before or during the application of the predosed sealing compound. This can be achieved that the plasticity of the sealant is maintained even after application and this does not cease abruptly upon contact with the sealing surface.

This preheating of the sealing surface of the closure may, according to one embodiment of the invention, be carried out by induction heating, according to another embodiment by means of infrared heating. It is understood that different types of heaters can also be combined with each other.

More preferably, at least the sealing surface of the closure is coated with a coating to provide a bond with the sealant applied thereon. This coating can promote adhesion of the sealant to the sealing surface. Under certain circumstances it may be necessary for this purpose to thermally activate the coating, for example by heating the closure as described above. The coating can be formed as a lacquer, as a single- or multi-layer coating or lamination or the like.

Preferably, the bond between the sealant of the coating is produced by heating the coating and / or the sealant.

According to another preferred embodiment of the invention, the step of pre-metering the sealant and the step of applying the pre-metered sealant are performed simultaneously.

According to a further preferred embodiment of the present invention, the metered in the step of predosing the sealant sealant is present as granules. The predosing can be done in this case by the fact that individual granules are produced by the predosing, or in that individual granules are selectively separated from a supply of granules.

According to a further preferred embodiment of the invention, the pre-metered sealant is present as a strip, rod, wire or ring. This ring may be a welded (endless) or open ring, which in the basic form corresponds to the seal to be made and is only placed on / in the closure, plasticized and its e.g. circular cross section must be converted to the cross section of the final seal.

This predosed strip, the rod or the wire is further preferably formed into an open or closed ring, which corresponds in its basic form of the seal to be produced.

According to a further embodiment of the invention, the sealant in the predosing is punched out of a film in a ring-shaped or disc-shaped manner such that the predosed sealant is in the form of a ring or disc.

The present invention further relates to a closure for a container comprising a seal made according to the methods described above.

• - eine Dosiereinrichtung zur Vordosierung einer Dichtungsmasse, die ein Polymer enthält,
• - eine Plastifizierungseinrichtung zur Plastifizierung der vordosierten Dichtungsmasse mittels Ultraschall,
• - und eine Einrichtung zum Aufbringen der vordosierten Dichtungsmasse auf die Dichtungsfläche.

A device according to the invention for producing a closure for a container, which is provided with a seal on a sealing surface, comprises:

• a metering device for pre-metering a sealant containing a polymer,
• a plasticizer for plasticizing the pre-metered sealant by means of ultrasound,
• - And means for applying the pre-metered sealant on the sealing surface.

Preferably, this device comprises a forming device for forming the sealant on the sealing surface under mechanical pressure.

More preferably, the means for applying the pre-metered sealant to the sealing surface comprises at least one applicator, and the applicator and the shutter are movable relative to each other.

Further preferably, the forming device comprises at least one forming die, wherein the forming die are movable under shutter relative to each other.

According to a preferred embodiment of the device according to the invention, the forming punch and the application punch are identical.

Further preferably, the forming die and / or the applicator are formed as a sonotrode for transmitting ultrasound to the sealant and for plasticizing the same. In this case, for example, a forming die, which is formed separately from an applicator, may be formed as a sonotrode, or the applicator can form the sonotrode, or a stamp, which simultaneously forms the forming die and the applicator, serves as a sonotrode for plasticizing the sealant ,

According to a further preferred embodiment, the applicator is movable within a channel in which the pre-metered sealant is introduced laterally by the metering device.

Further preferably, this channel is annular, or a plurality of such channels, in each of which an applicator is movable, are arranged in a ring. This ring or this annular arrangement can advantageously correspond to the final shape of the seal to be produced.

According to a further embodiment of the present invention, the metering device comprises at least one metering channel, in which the pre-metered sealant is conveyed and which open from the outside substantially radially or tangentially into the annular channel or the annularly arranged channels, in which or which of the applicator or the applicator is or is mobile. In the case of an annular channel, the tangential introduction provides the advantage of a substantially barrier-free transition at the mouth of the metering channel into the annular channel in which the applicator die is guided. Ideally, then the entire annular channel can be filled by the pre-metered sealant is pushed along the ring until the ring is completely or at least approximately closed.

Further preferably, the metering device comprises at least one Dosierstempel which is movable to convey the pre-metered sealant.

This Dosierstempel is preferably designed as a sonotrode for contact transfer of ultrasound to the sealant for plasticizing the same.

According to a further preferred embodiment of the invention, the metering device for singulating granules is provided from a supply of a sealant present in the form of granules.

According to a further embodiment, the metering device is provided for separating a section from a strand of a strand-shaped sealant.

According to a further preferred embodiment, the metering device is provided to insert a portion of the sealant in an annular channel in which an annular applicator is movable, such that the portion assumes an at least approximately closed ring shape.

Further preferably, the device according to the invention comprises a heating device for heating the closure, which is designed as induction heating or as infrared heating.

According to a further preferred embodiment, the device according to the invention comprises a cooling device for cooling the forming die and / or the application stamp.

• 1a) bis 1f) sind perspektivische Ansichten eines Teils eines Innenbereichs eines Verschlusses für einen Behälter, zusammen mit vordosierter Dichtungsmasse sowie einer fertig ausgebildeten Dichtung;
• 2a) bis 2c) zeigt einen Teilschnitt durch eine Ausführungsform der erfindungsgemäßen Vorrichtung zur Herstellung einer Dichtung in oder auf einem Verschluss für einen Behälter;
• 3a bis 3d) ist ein Teilschnitt durch eine weitere Ausführungsform einer erfindungsgemäßen Vorrichtung, in Perspektiven ähnlich 2, zur Darstellung eines erfindungsgemäßen Verfahrensablaufs zum Betrieb der Vorrichtung;
• 4 und 5 sind schematische Darstellungen von Anordnungen von Kanälen zur Führung eines Aufbringstempels innerhalb einer erfindungsgemäßen Vorrichtung;
• 6a) bis 6d) zeigen schematisch einen Verfahrensablauf gemäß einer Ausführungsform der Erfindung zum Betrieb einer erfindungsgemäßen Vorrichtung zur Herstellung einer Dichtung in einem Behälter;
• 7a) bis 7e) zeigen eine weitere Ausführungsform des erfindungsgemäßen Verfahrens in verschiedenen Verfahrensschritten;
• 8a) und 8b) sind horizontale Schnitte durch eine weitere Ausführungsform einer erfindungsgemäßen Vorrichtung in verschiedenen Betriebszuständen;
• 9a und 9b) sind horizontale Teilschnitte durch eine weitere Ausführungsform der erfindungsgemäßen Vorrichtung in verschiedenen Betriebszuständen; und
• 10a) bis 10c) sind weitere Teilansichten der in 8 gezeigten Ausführungsform der erfindungsgemäßen Vorrichtung in verschiedenen Betriebszuständen.

In the following, preferred embodiments of the present invention will be explained in more detail with reference to the drawing.

• 1a 1f) are perspective views of a portion of an interior portion of a closure for a container, along with pre-dosed sealant and a completed seal;
• 2a 2c) shows a partial section through an embodiment of the device according to the invention for producing a seal in or on a closure for a container;
• 3a to 3d ) is a partial section through a further embodiment of a device according to the invention, similar in perspectives 2 , for illustrating a method sequence according to the invention for operating the device;
• 4 and 5 Fig. 3 are schematic representations of arrangements of channels for guiding an applicator within a device according to the invention;
• 6a ) to 6d) show schematically a method sequence according to an embodiment of the invention for operating a device according to the invention for producing a seal in a container;
• 7a ) to 7e) show a further embodiment of the process according to the invention in various process steps;
• 8a ) and 8b) are horizontal sections through a further embodiment of a device according to the invention in different operating states;
• 9a and 9b ) are horizontal partial sections through a further embodiment of the device according to the invention in different operating conditions; and
• 10a ) to 10c) are further partial views of in 8th shown embodiment of the device according to the invention in different operating conditions.

1 shows a closure 10 for a container, not shown. The closure 10 has a floor 12 on, which is circular in shape and from the edge of a cylindrical wall 14 extends upwards. When the container is closed, the bottom closes 12 of the lock 10 the opening of the container. So the shutter 10 closes tightly, it is provided on its inside with a seal which rests on the edge of the opening of the container and is pressed against it, so that the wall 14 of the lock 10 includes the edge. The wall 14 may also be provided in a known manner with internal engagement elements to form a screw cap or the like on the container. Such elements are omitted here, they are not the subject of the present invention.

The seal 16 is according to 1f ) in finished trained state of the closure 10 in an annular groove 18 ( 1a ) to 1f)) and is itself ring-shaped. It consists of a polymer, in the following case of a thermoplastic polymer (TPE), which is plasticizable under heat and is substantially unplasticized at room temperature. The term "plasticized" is intended to mean a state in which the sealant is used to form the seal 16 is relatively malleable while the seal 16 is dimensionally stable at room temperature. This does not preclude a certain elasticity of the finished seal, but rather such elasticity may be required for the sealing properties. In particular, the seal 16 be compressible to seal the container by means of the closure 10 to achieve the desired sealing properties.

To form the seal 16 the sealant is predosed according to the invention. This can be done in various forms in the 1b ) to 1e). According to 1b ) places the pre-dosed sealant in the form of granules 20 in front. These granules 20 be along the annular groove 18 for receiving the seal 16 distributed and plasticized by means of ultrasound, as will be explained in more detail below. By this plasticization by means of ultrasound, as well as by an optionally carried out deformation under mechanical pressure, the granules flow 20 to form a ring and form the final shape of the seal 16 , as in 1f ). The most uniform possible distribution of the granules 20 along the annular groove 18 is beneficial to a uniform design of the seal 16 to reach.

The inside of the groove 18 thus forms a sealing surface 22 to which in the form of granules 20 pre-dosed sealant is first applied and then plasticized. The plasticization can also take place during the application of the premetered sealant according to a further embodiment of the method according to the invention, or the predosed sealant is applied to the sealing surface before application 22 in the groove 18 plasticized. This will be explained in more detail.

1c ) shows another embodiment in which the pre-metered sealant as a ring 24 is present. This ring 24 can be completely closed, or, as in 1c ) demonstrated in one place 26 to be open. In the present case it is a ring 24 with a circular cross-section, ie a so-called O-ring.

According to the embodiment in FIG 1d ), the pre-metered sealant is in the form of a number of individual ring segments 27 before, which together form a ring and accordingly along the groove 18 on the sealing surface 22 be distributed. These ring segments are shown here as arcuate strips or wires, but may also be formed as a straight strip or rods and so on the sealing surface 22 be distributed, that results after plasticizing and forming a closed seal.

1e ) shows a closed ring 28 which forms the pre-metered sealant. This ring 28 However, it has a different cross-section than the ring 24 in 1c ), namely a rectangular flat cross-section.

For plasticizing according to the 1b ) to 1e) predosed sealant serves a stamp 30 from the top, ie from the inside of the closure forth on the pre-dosed and on the sealing surface 22 applied sealant is pressed. The Stamp 30 is designed as a sonotrode for transmitting ultrasonic vibrations to the sealant.

The Stamp 30 may be an application stamp that serves to apply the pre-metered sealant to the sealing surface 22 apply as well as also a forming die that transforms the already applied sealant, or by a stamp that simultaneously performs the functions of applying and reshaping. In this case, application stamps and forming dies are identical parts.

2 shows various partial sections through a device for producing a closure 10 , as in 1 pictured on his sealing surface 22 with a seal 16 according to 1f ) is provided.

2a ) to 2c) show a part of a vertical section through a device 50 for the production of the closure 10 according to an embodiment of the present invention, with a tool 52 against which the shutter 10 ( 2c ) is movable in a vertical direction from below (arrow A) that the ground 12 against the bottom 56 a lower tool punch 54 of the tool 52 is moved. Inside the tool stamp 54 runs a vertical channel 58 that to the bottom 56 is open and over the area of the floor 12 opens, in which the groove 18 with the sealing surface 22 runs. Within this channel 58 is a stamp 60 movable upwards and downwards, from a top dead center in 2a ) is shown at a bottom dead center in 2c ), at which the lower end of the punch 60 from the bottom 56 of the tool stamp 54 protrudes.

Laterally empties into the canal 58 a dosing channel 62 , Within the dosing channel 62 is a Dosierstempel 64 horizontally movable. From the top opens into the dosing 62 a filling channel 66 , This contains a sealant in the form of a series of granules 20 (in the following simply as grains 20 designated). The filling channel 66 has a diameter that is not or not significantly larger than the diameter of the grains, so the grains 20 stacked one above the other in the filling channel and by their own weight down into the dosing 62 can slip. Whose Diameter corresponds approximately to the diameter of the filling channel 66 , ie the height of the dosing channel 62 and the grain size are adapted to each other so that a grain in the height direction of the dosing 62 fills, an overlying grain but not in the dosing 62 can guess. It can therefore only the lowest grain of the filling channel in each case 66 present stack in the dosing 62 fall.

This situation is in 2a ). The Dosierstempel 64 is completely withdrawn here, leaving the lower mouth of the filling channel 66 to the dosing channel 62 is free. The lowest grain 68 the sealant can then in the dosing 62 fall and by a movement of the dosing 64 in the direction of the canal 58 captured and in the channel 58 be inserted ( 2 B ).

The Dosierstempel 64 serves in the present embodiment thus as a metering device for separating a used to form the seal part of the sealant from a supply of granules 20 , As a result, a predosing of the sealant takes place. In an alternative embodiment, in the filling channel 66 Also sealant in rod or wire form, so as a stock strand, introduced and the Dosierstempel the grain 68 be separated as pre-metered sealant.

The Dosierstempel 64 however, in the present embodiment also serves to plasticize the pre-metered sealant, as in FIG 2 B ) is shown. For this purpose, the Dosierstempel 64 trained as sonotrode. As a result, ultrasonic vibrations on the isolated and in the channel 58 transported grain 68 transfer. This will cause the grain 68 the sealant melted, at least to such an extent, that it becomes the final shape of the seal 16 deform. This can, as will be explained in more detail below, done by additional mechanical deformation. Conceivable, however, are embodiments of the invention in which the sealant is melted so far that they automatically within the groove 18 in the final form of the seal 16 flows.

In the present embodiment, in the situation in FIG 2 B ) plasticized grain 68 from the applicator 60 during which downward movement is detected after or during the dosing 64 retreats ( 2c ), and the grain 68 gets down into the groove 18 on the sealing surface 22 pressed. In this way, the pre-metered sealant on the sealing surface 22 of the lock 10 applied. The Stamp 60 thus serves as an applicator and thus as a means for applying the predosed sealant on the sealing surface 22 , or is part of the same.

According to the present embodiment, the application punch serves 60 at the same time as forming stamp. It exerts mechanical pressure on the sealant so that several along the groove 18 distributed grains 68 (as in 1b ) to the annular seal 16 connect. As will be shown in more detail below, namely several channels 58 annular within the tool punch 54 according to the shape of the groove 18 and the final seal 16 arranged, together with corresponding arrangements of Dosierkanälen 62 , Dosing stamps 64 and filling channels 66 , as in 2a to c). However, it is also conceivable according to a further embodiment, the arrangement of an annular or cylindrical channel 58 in which the application stamp 60 or forming punch is movable.

The forming by the applicator 60 or forming die can be supported by the fact that this is also designed as a sonotrode and thus the in the groove 18 introduced sealant is additionally plasticized. That is, the seal 16 is under the action of heat and mechanical pressure through the applicator 60 or formed forming stamp. The plasticization of the pre-dosed sealant by means of ultrasound and the application of the pre-dosed sealant to the sealing surface can thus take place simultaneously, or the plasticization can take place before application, in the form of complete or partial plasticization of the pre-dosed sealant. However, it is conceivable according to another embodiment, the pre-metered sealant first on the sealing surface 22 inside the groove 18 apply and then plasticize, such as by a subsequently applied forming die, which is also designed as a sonotrode.

It is also possible the closure 10 by an additional heating device of the device 50 To heat up, such as by induction heating or infrared heating, so that a plastification of the sealing surface 22 applied sealing compound is promoted. On the other hand, an applicator can 60 and / or forming die to be cooled.

3a ) to 3d) show a partial section through an embodiment of the device according to the invention 150 that of the device 50 out 2 regarding the course of the channel 58 in which the application stamp 60 or forming die is guided vertically, the dosing 62 with the horizontally movable Dosierstempel 64 , and the filling channel 66 that with granules 20 of the Sealant is filled, is similar. The transport of a single grain 68 through the Dosierstempel 64 within the dosing channel 62 in the channel 58 ( 3a and b)) is essentially the same 2 , However, in the present embodiment, the metering die is 64 not designed as sonotrode, but the grain 68 is in the non-plasticized state in the channel 58 from the applicator 60 recorded, transported down ( 3c ) and on the sealing surface 22 applied ( 3d ). The applicator stamp 60 is also formed in this case as a forming die and at the same time designed as a sonotrode. This will affect the sealing surface 22 applied sealant plasticized and reshaped under mechanical pressure. In this case, it is possible to plasticize and reform the pre-metered sealant even after it has been applied to the sealing surface 22 so already after the sealant makes contact with the sealing surface 22 has, or meanwhile.

The 4 and 5 show two different arrangements according to different embodiments of the in the 2 and 3 illustrated devices 50 and 150 , According to 4 are separate channels 58 annular within the tool punch 54 arranged so that they are in the operation of the devices 50 and 150 in the 2 and 3 is shown, just above the groove 18 and thus those from these channels 58 downwards leaking sealant directly into the groove 18 is introduced, as already shown above. The from the channels 58 down grains 68 The pre-metered sealant are then initially in an arrangement according to 1b ), ie, they are isolated from each other along the annular groove 18 and become the annular seal by subsequent forming and / or plasticizing 16 according to 1f ) transformed.

According to 4 run the dosing channels 62 radially to the center of the tool punch 54 and the ring along which the channels 58 are distributed. The diameter of each channel 58 in the horizontal plane is circular and corresponds approximately to the diameter of a grain 68 or is slightly larger. In the upper area of 4 is an arrangement of applicator punches 60 represented in their form the in 4 channels shown below 58 correspond, ie each of these applicator 60 has about the shape of a cylindrical pin, which is inside a channel 58 is led down.

According to the embodiment in FIG 5 is a circumferentially closed annular channel 158 provided in which the grains 68 the granules of the sealant are transported radially from the outside. The horizontal cross section of the annular channel 158 corresponds to the ring shape of the finished seal 16 , Within this annular channel 158 may also be a ring-shaped applicator 160 move up and down. Is the applicator 160 At the same time provided as a forming die, in connection with the 2 and 3 described, the pressure surface of the applicator 160 or Umformstempels for exerting a uniform pressure over the entire surface of the seal 16 serve and thus contribute to the uniform formation of the seal. As already described, the applicator can 160 or forming die to be designed as a sonotrode.

6 shows a further embodiment of a device 250 according to the present invention, to form a seal 16 on a sealing surface 22 a lock 10 , A partial section through the lock 10 is in 6a ). According to 6b ) lead the lock 10 and a tool stamp 154 a relative movement to each other in the vertical direction, such that the tool punch 154 and the closure 10 be moved towards each other. The sealant to form the seal 16 in the present case has already been predosed by a metering device, not shown, and on the sealing surface 22 the groove 18 in the ground 12 of the container 10 been applied. This can be carried out in a preceding method step, for example by a in 6 not shown in detail tool from the tool punch 154 is disconnected.

Within the in 6b ) illustrated tool stamp 154 is a forming stamp 162 within an annular channel 164 vertical relative to the tool punch 154 movable. This annular channel 164 can be a shape according to the channel 158 in 5 have, and accordingly, the forming die 162 a mold according to the applicator or forming die 160 in 5 exhibit.

According to 6c ) becomes the soil 12 of the container 10 against the bottom 166 of the tool stamp 154 pressed while the forming punch 162 in a slightly raised position within the annular channel 164 located such that the lower mouth end 168 of the annular channel 164 remains free. Only in the situation in 6c ), in which the ground 12 the bottom 166 of the tool stamp 154 is contacted, the forming die 162 pressed down and forms the in the groove 18 embedded sealant to the final seal 16 , as in 6d ).

Also in the present embodiment, the forming die 162 be designed as a sonotrode, so that the mechanical pressure through the forming die 162 with the simultaneous action of ultrasound to plasticize the sealant is exercised.

The sealant may in the embodiment in 6a ) to d) are also present in other forms than in granular form. In particular, predosing the sealant according to 1c ), d) and e), ie in the form of a ring which is closed or opened, or in the form of ring segments.

7 shows a further embodiment of the method according to the invention for producing a seal in a closure 110 for a container. In the present embodiment, the shutter is 110 a crown cap for closing a bottle, not shown. The closure 110 is therefore with a floor 112 and a beaded edge 114 trained the ground 112 circulates annularly.

The top of the floor 112 forms in this case the sealing surface 122 , This sealing surface 122 is coated to create a bond with the sealant applied thereto. This coating can be thermally activated, ie in particular plasticized, so that it forms a bond with the applied sealant. For this purpose, the shutter 110 heated. According to 7a ) preheating takes place by means of induction heating, or alternatively, according to a further embodiment, by means of an infrared heater.

According to 7b ) is in the middle of the sealing surface 122 a grain 68 applied a granulate of the sealant. For this purpose, a device is used 850 with a tool 254 in which a vertical channel 258 runs, which is open at its lower end. Within this channel 258 is an application stamp 260 movable upwards and downwards. Side opens a horizontal dosing 262 in the vertical channel 258 , and within this dosing channel 262 is a Dosierstempel 264 movable. From the top opens a vertical filling channel 266 in the dosing channel 262 , Inside the filling channel 266 is a number of grains of a granule 20 arranged the sealant.

In the same way as in the 2 and 3 , serves the Dosierstempel 264 to do so, from a withdrawn position, as in 7b ), a lowest grain 68 of the granules 20 to capture and into the vertical channel 258 insert. This grain 68 can then from the applicator 260 Detected from above and down through the opening of the vertical channel 258 from the tool 254 and also the coated sealing surface 122 to be brought. As a result, then there is a single grain 68 the sealant on the coated sealing surface 122 on.

The arrangement of the vertical channel 258 with the applicator stamp 260 , of the dosing channel 262 with the Dosierstempel 264 and the filling channel 266 is thus similar to the 2 and 3 , except that the vertical channel 258 from which the grain 68 is applied downward, centrally over the closure 110 is arranged. Also in the present embodiment, the Dosierstempel 264 and / or the applicator 260 as a sonotrode for plasticizing the grain 68 be educated. It is conceivable, for example, that the grain 68 of the granules 20 the sealant first by the Dosierstempel 264 is preplasticized and by the applicator 260 is completely plasticized. Plastification and application of the pre-dosed sealant can thus also be carried out simultaneously or in succession. The plasticization can also take place before application. It is also conceivable that the applied grain 68 in the 7b ), in which it is already on the coated sealing surface 122 by heating the closure 110 is plasticized.

According to 7c ) becomes the grain 68 the sealant by a forming die 270 pressed from the top into the shutter 110 is moved in. By this pressing, the sealant of the grain is distributed 68 over the entire sealing surface 122 , as in 7d ). The entire floor 112 of the lock 110 is then covered by the sealant, as in 7e ) is shown. The forming stamp 270 may be provided on its underside with a profiling, such as an annular profiling to form the seal accordingly.

The forming stamp 270 can itself be designed as a sonotrode again. It is also possible to use the forming punch 270 to cool.

8a ) and b) show a horizontal partial section through a further embodiment of a device 350 for forming a seal, in the present case an annular seal, in or on a closure, not shown, for a container 10 , The sealing material is here strand-like and is by a metering device, which is part of the device 350 is predosed to individual strands cut off from a supply strand.

The device 350 includes a tool 354 with an annular channel 358 in which a in 8a ) and b) not shown applicator 360 is movable perpendicular to the plane of the drawing. In this annular channel 358 opens laterally a dosing 362 through which a strand of the sealant in the direction of the annular channel 358 is pushed. This strand may in particular be a polymer wire.

To advance the strand 324 serves a feed device 364 , the two in the present case 324 oppositely arranged and counter-rotating conveyor rollers 366 includes. These conveyor rollers 366 lie on the opposite outer sides of the strand 324 and promote this to a cutting tool 368 that is for severing a section of the strand 324 serves.

According to 8a ) becomes the strand 324 initially from the dosing channel 362 so far in the annular channel 358 inserted that the section formed herein 370 of the strand 324 is almost decided. In this situation, the cutting tool becomes 368 operates and separates the leading section of the strand 324 from.

As in 8b ), then the feed device 364 continue to operate until the rear severed end 372 of the leading section of the strand 324 completely in the annular channel 58 occurred. At the same time, the leading end of the strand becomes 324 along the circumference of the annular channel 358 pushed further, ie its leading end 374 pushes further in the direction of the mouth of the dosing 362 , The resulting annular section 370 is then almost completely closed and is present as a predosed ring of the sealant. This ring can then be detected by the applicator and applied to the sealing surface.

9a ) and b) show a further embodiment of the device according to the invention 450 , also with an annular channel 458 , for receiving an annular portion 470 a polymer wire as a pre-dosed sealant, which is of one strand 424 is cut off. The dosing channel 462 also runs here on the annular channel 458 to the side, but is arranged approximately tangentially to this. The feed device 464 corresponds to those in the 8a ) and b) with the reference number 364 is designated.

The cutting tool 468 is in this case a cutting punch, which is transverse to the strand 424 and approximately radially to the center of the annular channel 458 is mobile. 9a ) shows the cutting punch 468 in a position in which the strand 424 free in the annular channel 458 is retractable until the leading end 474 of the strand 424 back to the cutting tool 468 and thus the mouth of the dosing 462 approaches. In this situation, the cutting punch is operated as in 9b ), and the cutting punch 468 shears the strand 424 radially inward and pushes the severed rear end 472 in the canal 458 enclosed annular portion 470 of the polymer wire in the channel 458 into it. This creates an almost completely closed ring of pre-dosed sealant.

The 10a ) to c) show a further section through the embodiment of the device 350 out 8a ) and b). The cutting plane runs vertically through the tool 354 , The closure 10 in which the seal 16 is formed is also shown. Inside the tool 354 is a horizontal support plate 376 in, in a position below the mouth of the metering 362 in the annular channel 358 , This support sheet 376 serves to support the annular portion 370 the sealant, if this in the annular channel 358 is inserted. 8b ) shows the process of detecting the inside of the annular channel 358 pre-dosed sealant by a molding die 160 which also serves as a forming die in the present embodiment. The annular pre-dosed sealant is down from the applicator or forming die 160 on the sealing surface 22 brought after the support sheet 376 removed, ie laterally from the tool 454 has been pulled out ( 10c )).

It is noted that in embodiments, different from the device 350 and 450 according to the 8th . 9 and 10 can be dispensed with a separate cutting tool and instead the separation of the annular portion 370 respectively. 470 from the strand 324 . 424 by the application stamp or forming punch 160 can be made. This application stamp or forming punch 160 then disconnects during its movement within the channel 358 . 458 the strand 324 . 424 off (in 10b ) and moves the severed portion down onto the closure 10 ,

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 2012/0171381 A1 [0003, 0004]
• US 2016/0318212 A1 [0003, 0004]
• US 2011/0100994 A1 [0003, 0006]

Claims (32)

Method for producing a seal (16) in or on a closure (10, 110) for a container, characterized by the following steps: a) pre-metering of a sealant containing a polymer, b) plastification of the pre-dosed sealant by means of ultrasound, c) Applying the premetered sealant to a sealing surface (22) of the closure (10, 110), wherein step b) is optionally performed before, after or simultaneously with step c). Method according to Claim 1 , characterized in that the sealing compound applied to the sealing surface in step c) is deformed under mechanical pressure. Method according to Claim 1 , characterized in that the sealant is formed under mechanical pressure during the application performed in step c) on the sealing surface (22). Method according to Claim 2 or 3 , characterized in that the deformation is carried out in the at least partially plasticized state of the sealant. Method according to one of Claims 2 to 4 , characterized in that a tool used for forming is cooled during the forming. Method according to one of the preceding claims, characterized in that at least the sealing surface (22) of the closure is preheated before or during the application of the predosed sealing compound carried out in step c). Method according to Claim 6 , characterized in that the preheating is carried out by means of an induction heater. Method according to Claim 6 , characterized in that the preheating is carried out by means of an infrared heater. Method according to one of the preceding claims, characterized in that at least the sealing surface (22) of the closure is coated with a coating to create a bond with the sealant applied thereto. Method according to Claim 9 , characterized in that the bond is produced by heating the coating and / or the sealant. Method according to one of the preceding claims, characterized in that steps a) and c) are carried out simultaneously. Method according to one of the preceding Claims 1 to 11 , characterized in that the pre-metered in step a) sealant is present as granules (20). Method according to one of the preceding Claims 1 to 11 , characterized in that the pre-metered in step a) sealant is present as a strip, rod, wire or ring. Method according to Claim 13 characterized in that the pre-metered strip, rod or wire is formed into an open or closed ring (24, 28). Method according to one of the preceding Claims 1 to 11 , characterized in that in step a) the sealant is punched annular or disc-shaped from a foil, such that the predosed sealant is present as a ring or disc. A closure for a container comprising a seal made by a method according to any one of Claims 1 to 15 , Apparatus (50, 150, 250, 350, 450, 850) for manufacturing a closure (10, 110) for a container, which closure (10, 110) is provided on a sealing surface (22) with a seal (16) : a metering device for pre-metering a sealant containing a polymer, a plasticizer for plasticizing the pre-metered sealant by means of ultrasound, - And means for applying the pre-metered sealant on the sealing surface (22). Device according to Claim 17 , Further characterized by a forming device for forming the sealant on the sealing surface (22) under mechanical pressure. Device according to one of the Claims 17 or 18 characterized in that the means for applying the pre-metered sealant to the sealing surface comprises at least one applicator punch (30, 60, 160, 260) and the applicator punch (30, 60, 160) and the closure (10, 110) are movable relative to each other , Device according to one of the Claims 17 to 19 , characterized in that the Forming device comprises at least one forming die (30, 162, 270) and the forming die (162, 270) and the closure (10, 110) are movable relative to each other. Device according to Claim 20 combined with Claim 19 , characterized in that the forming die (30, 162, 270) and the applicator punch (30, 60, 160, 260) are identical. Device according to one of the Claims 19 to 21 , characterized in that the forming die (30, 162, 270) and / or the applicator punch (30, 60, 160, 260) is or are formed as a sonotrode for contact transfer of ultrasound to the sealant for plasticizing the same. Device according to one of the Claims 19 to 22 , characterized in that the applicator (30, 60, 160, 260) within a channel (58, 158) is movable, in which the pre-metered sealant is introduced laterally by the metering device. Device according to Claim 23 , characterized in that the channel (58, 158) is annular or a plurality of such channels, in each of which an applicator is movable, are arranged in a ring. Device according to Claim 24 , characterized in that the metering device comprises at least one metering channel (62, 262, 362) in which the pre-metered sealant is conveyed and which from the outside substantially radially or tangentially in the annular channel (58, 158, 358, 458) or annularly arranged channels open, in which or which of the or applicator (30, 60, 160, 260) is movable or are. Device according to one of the Claims 17 to 25 , characterized in that the metering device comprises at least one Dosierstempel (64, 264) which is movable to convey the predosed sealant. Device according to Claim 26 , characterized in that the Dosierstempel is designed as a sonotrode for contact transfer of ultrasound to the sealant for plasticizing the same. Device according to one of the Claims 17 to 27 , characterized in that the metering device for singulating granules (20, 68) is provided from a supply of a sealing compound present as granules. Device according to one of the Claims 17 to 27 , characterized in that the metering device is provided for separating a portion of a strand (324, 424) of a strand-shaped sealant. Device according to Claim 29 , characterized in that the metering device is provided to insert a portion of the sealant into an annular channel (358, 458) in which an annular applicator is movable, such that the portion assumes an at least approximately closed ring shape. Device according to one of the Claims 17 to 30 characterized by a heating device for heating the closure (10, 110), which is designed as induction heating or as infrared heating. Device according to one of the Claims 17 to 31 characterized by cooling means for cooling the forming die (30, 162, 270) and / or the applicator die (30, 60, 160, 260).

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