Method, tool and assembly for tightly closing a receptacle, and tightly closed receptacle
11590554 · 2023-02-28
Assignee
Inventors
Cpc classification
B65B7/28
PERFORMING OPERATIONS; TRANSPORTING
B21D51/2661
PERFORMING OPERATIONS; TRANSPORTING
International classification
Abstract
The present invention aims at closing a receptacle (1) provided with an opening (2) as tightly as possible while keeping low the amount of material required for a closure (3) used for this purpose. To this end, a tool (10) is suggested that closes the opening (2) of the receptacle (1) by means of the closure (3). The tool (10) comprises a tool plate (12) configured such that it is adapted to be introduced into the opening (2) of the receptacle (1). The tool further comprises at least one roll (11) that is arranged on the tool plate (12). The at least one roll (11) is adapted to be deflected radially outwards from a starting position into a closing position and returns to its starting position, so that a radial force can be caused to act on a closure rim (4) of the closure (3) for a limited period of time, the closure rim (4) being arranged between the at least one roll (11) and the receptacle inner side (5).
Claims
1. A tool for closing an opening (2) of a receptacle (1) having a receptacle inner side (5) by a closure (3), the tool (10) comprising: (a) a tool plate (12) that is adapted to be introduced in an opening (2) of the receptacle (1) to be closed; (b) at least one roll (11) arranged on the tool plate (12) in a starting position (13), the at least one roll (11) being deflectable radially outwards to a closing position (14) and returnable to its starting position (13), so that a radial force can be caused to act on or can be applied to a closure rim (4) of the closure (3) for a limited period of time, the closure rim (4) being arranged between the at least one roll (11) and the receptacle inner side (5); and (c) wherein an outer surface of the at least one roll has a cylindrical shape with a constant diameter over its entire height to engage the closure rim.
2. The tool according to claim 1, wherein the tool plate (12) has arranged thereon two rolls (11), three rolls (11), four rolls (11), five rolls (11), six rolls (11), seven rolls (11), eight rolls (11) or more than eight rolls (11).
3. The tool according to claim 1, wherein the tool comprises a positioning element (15) for introducing the closure (3) into the receptacle (1).
4. The tool according to claim 1, wherein the at least one roll (11) is deflectable by a defined force.
5. An assembly comprising a tool for closing an opening (2) of a receptacle (1), having receptacle side wall inner side (5) comprising a vertically extending portion, and a shaft (21), the tool (10) comprising: (a) a rotating tool plate (12) that is adapted to be introduced in an opening (2) of the receptacle (1) to be closed; (b) at least one roll (11) having a constant diameter over a height thereof and being arranged on the rotating tool plate (12), wherein from a starting position (13), the at least one roll (11) being deflectable radially outwards to a closing position (14) and returnable to the starting position (13), to provide a radial force to a closure rim (4) of a closure (3) by the at least one roll (11) with the constant diameter of the height for a limited period of time; and (c) the closure rim (4) being arranged between the at least one roll (11) having the constant diameter and the vertically extending portion of the receptacle side wall inner side (5) and the closure rim contacting the vertically extending portion of the receptacle side wall inner side, when the radial force is applied; wherein the shaft (21) is connected to the tool (10) to transmit a torque to the tool (10).
6. The assembly according to claim 5, wherein, in addition to transmitting a torque to the tool (10), the shaft (21) is also axially displaceable or extendable.
7. The assembly according to claim 5, comprising a lifting device (22) that is arranged such that a receptacle (1) with an opening (2) to be closed can rest thereon and that, through a movement of the lifting device (22), the tool (10) can be received by the receptacle (1) with the opening (2).
8. The assembly according to claim 5, comprising a heating element (23).
9. The assembly according to claim 8, wherein the heating element (23) is arranged between a centerline of the rotating tool plate (12) and the at least one roll (11) or is arranged radially outside of the receptacle (1).
10. The assembly according to claim 8, wherein the heating element (23) is configured as an induction element, as an electric heating element or as a heat radiator element.
11. The assembly according to claim 5, comprising a guide ring (25) and a lifting device (22), wherein the lifting device (22) is arranged such that a receptacle (1) with an opening (2) to be closed can rest thereon and that, through a movement of the lifting device (22), the receptacle (1) can be moved over the tool (10).
12. The assembly according to claim 11, wherein the guide ring (25) is able to receive the receptacle (1) therein such that the receptacle (1) occupies a defined position and is able to guide the receptacle over the tool (10) under preload of a spring.
13. A method of closing an opening (2) of a receptacle (1) having a receptacle side wall inner side (5) with a vertically extending portion and a receptacle interior (6), the method comprising the following steps: (a) providing a receptacle (1) having at least one opening (2) to be closed; (b) introducing a closure (3) into the opening (2) of the receptacle (1), the closure (3) having a closure rim (4) directed away from the receptacle interior (6), and an axial basic shape of the closure rim (4) corresponds to an axial basic shape of the receptacle (1); (c) introducing a rotatable tool (10) into a space, open on one side thereof and delimited by the closure (3); (d) deflecting at least one rotatable roll (11) having a constant diameter over a height thereof radially outwards, to-contact engaging the closure rim (4) of the closure (3); and (e) rotating, about a longitudinal axis, the rotatable tool (10), with the at least one rotatable roll (11) having the constant diameter of the height thereof engaging the closure rim (4), relative to the receptacle (1), or vice versa, and attaching the closure rim (4) to the vertically extending portion of the receptacle side wall inner side (5), to close the opening (2).
14. The method according to claim 13, wherein one side of the closure rim (4) has provided thereon a layer (7) that is brought into contact with the receptacle side wall inner side (5) and thermally liquefied before and/or while the rotatable tool (10) rotates relative to the receptacle (1), or vice versa.
15. The method according to claim 14, wherein thermal energy for liquefying the layer is transferred to the layer by heating at least one rotatable roll (11) and/or the receptacle (1) and/or the closure.
16. The method according to claim 13, wherein the closure (3) is introduced in the receptacle (1) via a positioning element (15) arranged on the rotatable tool (10).
17. The method according to claim 13, wherein, due to the rotation of the rotatable tool (10) or of the receptacle (1), the at least one rotatable roll (11) engaging the closure rim (4) rotates in a clockwise direction or in a counter-clockwise direction, so that the at least one rotatable roll (11) moves in a direction opposite to an upwardly formed step in a receptacle side wall.
18. The method according to claim 13, wherein, due to the rotation of the rotatable tool (10) or of the receptacle (1), the at least one rotatable roll (11) contacting the closure rim (4) rotates in a clockwise direction or in a counter-clockwise direction, so that the at least one rotatable roll (11) moves in a direction opposite to a downwardly formed step in a receptacle side wall.
19. A method of closing an opening (2) of a receptacle (1) having a receptacle inner side (5) and a receptacle interior (6) encompassed by the inner side as an inner surface, the method comprising the following steps: (a) the receptacle (1) providing at least one opening (2) to be closed; (b) introducing a closure (3) into the opening (2) of the receptacle (1), the closure (3) having a closure rim (4) directed away from the receptacle interior (6) and a closure panel (3a), whose circumferential basic shape corresponds to a circumferential basic shape of the receptacle (1) in at least an upper section thereof; (c) axially introducing a closure tool (10) into a space open on one side thereof and delimited by the closure panel (3a) on an opposite side thereof; (d) outwardly deflecting at least one rotatable roll (11), wherein the at least one rotatable roll has a cylindrical shape with a constant diameter over its entire height, engaging the closure rim (4) of the closure (3) with the cylindrical shape; and (e) applying a rotating movement of the closure tool (10) and the at least one rotatable roll (11) relative to the receptacle (1), to attach the closure rim (4) to the receptacle inner side (5), tightly closing the opening (2).
20. The method according to claim 19, wherein one side of the closure rim (4) has provided thereon a layer (7), the layer (7) being brought into contact with the receptacle inner side (5) and thermally at least softened before and/or during the rotating movement.
21. The method according to claim 20, wherein a thermal energy for liquefying the layer (7) is transferred to the layer by heating the at least one rotatable roll (11) and/or an upper section of the receptacle (1) and/or the closure (3).
22. The method according to claim 19, wherein the closure (3) is introduced in the receptacle (1) by a positioning element (15) arranged on the closure tool (10), the closure tool (10) and the closure (3) being-introduced in the receptacle (1) simultaneously.
23. The method according to claim 19, wherein, due to the relative movement of the closure tool (10) and of the receptacle (1), the at least one rotatable roll (11) contacting the closure rim (4) is rotatingly driven such that the at least one rotatable roll (11) moves towards an upwardly formed step (31) in a receptacle side wall.
24. The method according to claim 19, wherein, due to the relative movement of the closure tool (10) and of the receptacle (1), the at least one rotatable roll (11) engaging the closure rim (4) is rotatingly driven such that the at least one rotatable roll (11) moves towards a downwardly formed step in a receptacle side wall.
25. The method according to claim 19, wherein in feature (e) the closure rim (4) is fastened to an upper end section of the receptacle inner side (5) and the opening (2) of the receptacle (1) is tightly closed.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) The embodiments of the invention are shown on the basis of examples and not in a manner in which limitations from the figures are transferred to or read into the claims. Like reference numerals in the figures designate like elements.
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DETAILED DESCRIPTION OF THE INVENTION
(17) An example of the present invention is the tool 1 in
(18) In the present embodiment, the tool 10 comprises a plurality of rolls 11 which are circumferentially evenly arranged on the outer peripheral region of a tool plate 12. The rolls 11 are preferably cylindrical in shape, have an outer surface OS adapted to contact a closure rim 4 and have a height H11 that corresponds substantially to the height H4 of the closure rim 4 according to
(19) Each of the rolls 11 is connected to the tool plate 12 via a cantilever arm 16a and a joint 16. In addition, each of the rolls 11 is connected to a roll axle 17 along its respective longitudinal axis, the respective roll axle 17 being connected via a respective connection element 19 to a rod 18 (a plunger). A lifting device 19a makes each of the rods 18 extendable and retractable. For this kind of movement, the lifting device 19a is able to extend the rod 18 in a radial direction as well as to retract it in a negative radial direction (in the direction of the interior of the tool plate).
(20) The movement of the respective rod 18 can be transmitted via the respective connection element 19 to the respective roll axle 17, thus allowing each roll 11 to be retracted and extended independently.
(21) If the roll 11 is extended or deflected, a counterforce acting on the roll 11 can be taken up by the lifting device 19a (via the rod 18, the connection element 19 and the roll axle 17).
(22) The respective joint 16 guides and supports the movement of the respective roll (via a connection of the cantilever arm 16a with the roll axle 17 and the joint 16) during extension and retraction or during the outward deflection movement and the inward deflection movement.
(23) To the person skilled in the art it will be evident that such a tool 10 may also be configured in a different way, the aspects of the retractability and extendability of each of the rolls 11 and the possibility of taking up a force at the extended position sustain the function. In
(24) If a plurality of rolls 11 is provided, the above paragraphs should be read in the plural.
(25) Preferably, a layer 7 is provided between the closure rim 4 and the inner side 5 of the receptacle, the layer being configured as an adhesive layer or a connection layer.
(26) The layer 7 may be applied to one side of the closure 3 or to the surface of the inner side 5 of the receptacle.
(27) Preferably, the layer 7 is a sealing wax or a hot glue, particularly preferred the layer 7 comprises a material containing polyethylene and/or polypropylene. Such materials can be softened or even liquefied by heating; after having solidified or set, these materials connect the elements with which they entered into contact during softening or liquefying, i.e. the receptacle wall (inner side 5 of the receptacle and/or outer side 8 of the receptacle) and the closure rim 4.
(28) Before or during the rotation of the tool 10 relative to the receptacle 1, the softening or liquefying is thermally caused, so that at the point where the roll 11 enters into contact with the closure rim 4, a softened or liquefied layer of material will be present. By circulating the roll 11 along the circumferential closure rim 4 with a respective flowable material, an accumulation of material or a material wave 33 will form between the closure rim 4 and the inner side 5 of the receptacle, the material wave being, due to the movement of the roll 11, pushed forward ahead of the roll in the direction of movement of the latter. Such a material wave 33 is not a distinct wave, but an area of increased thickness of the layer 7 in a flowable state (thermally softened or liquefied) in comparison with the original thickness on one side of the closure rim 4 or on the inner side 5 of the receptacle.
(29) An illustrating view of this is schematically shown in Fig, 2c, and a geometrically more precise view is shown in
(30) According to a particularly preferred embodiment, the material wave 33 formed will fill the vertical seam 31 of a three-part can such that the closure rim 4 will be sealingly connected to the inner side 5 of the receptacle also in this sensible area. Thus, also these points will be acted upon by the roll 11, as has been mentioned hereinbefore.
(31) Preferably, the roll 11 moves in the direction of the vertical seam 31, in the case of which a step in this area represents a step formed upwards when seen in the direction of the roll 11 (the roll moves e.g. in a circumferential direction, the step of seam 31 rises in front of the roll in a negative r-direction). The opposite direction, in which an area formed as a downward step when seen in the direction of the roll 11, is sealed or adhesively bonded, is possible as well.
(32) This effect is also desired when glass receptacles are sealed, such glass receptacles having typically a longitudinal seam that results from the production process.
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(34) The positioning element 15 has provided therein guide tracks 15a, which are open at the edge side and which extend in an arcuate shape (on a respective circular path about the respective joint 16 at the distance of the respective arm 16a). The rolls 11 can be guided in the guide tracks, when a respective lower pin 17a of the respective roll axil engages the respective track 15a.
(35) In
(36) A further embodiment of a closure assembly is shown in
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(38) Since the centering ring 25 is arranged within the closure assembly 20 such that it is preferably centered with the tool 10, centering of the receptacle 1 and of the tool 10 will be guaranteed in this way.
(39) In order to allow a receptacle 1 to be closed, the receptacle 1 should—in cases where the tool 10 rotates—be secured against rotation. In other words, a torque, which will inevitably be transmitted to the receptacle 1 when the tool 10 rotates with the roll 11 being in its deflected condition, must be taken up, since otherwise the receptacle 1 will rotate about its longitudinal axis during the closing process, and this, in turn, will have undesirable disadvantageous effects during closing. Therefore, the receptacle 1 is fixed, through a small force, between the chamfer 28 of the centering ring 25 and an element on which the receptacle 1 rests. At any rate, the force suffices to produce between the chamfer 28 of the centering ring 25 and the rim 32 of the receptacle and between the receptacle bottom and the element on which the receptacle is located, respectively, a frictional force that is able to counteract the torque during the dosing process, without a rotation of the receptacle 1 taking place.
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(42) Within the scope of the present invention, a connection of a closure 3 may just as well be attached to the outer side 8 of the receptacle. An embodiment of this type is shown in
(43) In order to produce such a result, it will suffice to reconfigure a tool 10 only insignificantly in such a way that a roll 11 will be able to apply a force radially from the outer to the inner side. Preferably, a receptacle 1 according to this embodiment is sealed by introducing a holding element 24 into the space of a receptacle 1 such that, while applying pressure to, and possibly heating, the closure rim 4 from outside the can, the closure 3 located inside will be stabilized.
(44) To this end, the holding element 24 has a basic shape that corresponds to the basic shape of a receptacle 1 to be closed. The radial dimension of the basic shape of the holding element 24 is here slightly (less than 5%) smaller than the radial dimension of the basic shape of the receptacle 1, so as to allow the holding element 24 to be easily introduced in the space above the closure 3. The holding element 24 may here also fulfil the function of a positioning element 15, so that a closure 3 is introduced in a receptacle 1 by means of the positioning element 15 and the positioning element 15 remains, while the closure rim 4 is being pressed against the outer side 8 of the receptacle, at the position which it assumed for positioning the closure 3.
(45) Quite generally, the suggested tools 10 or the closure assembly 20 with the tool 10 are adapted to be used, where appropriate, for closing various receptacles 1 according to the method described, in addition to differences between the respective materials, the receptacles 1 may also substantially differ from one another with respect to their shape; it is, for example, also possible to close not only cylindrical receptacles 1 but also oval or polygonal receptacles 1. The same applies to integrally formed and multipart receptacles 1 (such as three-part cans). During the closing process, a receptacle 1 to be closed has preferably already been filled with a product to be filled.
(46) Depending on the material of the receptacle 1, different arrangements of a heating element 23 are preferably used. For example, according to a preferred embodiment, the heating element 23 is employed in the form of a heat radiator, e.g. as a laser or infrared radiator, acting from outside (outside of a receptacle 1), a course of action that is expedient especially in the case of metal receptacles. In the case of plastic receptacles 1 or receptacles 1 consisting of a composite material, the heating element 23 should preferably be arranged inside the tool 10 (between the area of the tool center and the roll 11).
(47) When an inductive element is used, the roll 11 may be heated, which will then transfer the heat to the layer 7 to be softened. Also the closure 3, which preferably comprises a certain percentage of aluminum, may be heated by an inductive element used as a heating element 23. An electric element used as a heating element 23 may provide heat outside of the receptacle 1 in the case of receptacles 1 consisting of metal, this also applies to receptacles 1 made of glass. When the receptacle 1 in question consists of thermally sensitive materials, it is, as a matter of principle, preferred to provide heat from the inner area. If receptacles 1 are sealed on the outer side 8 of the receptacle, the preferred position of a heating element 23 reverses, so that positions preferred inside will be preferred outside and vice versa.
(48) According to a further embodiment, a change in the direction of rotation of the roll 11 may be advantageous, so that, while the closure rim 4 is pressed against the inner side 5 or the outer side 8 of a receptacle 1, a clockwise movement of the roll 11 will take place, and when a closure rim 4 is pressed against a receptacle wall of a subsequent receptacle 1 an anticlockwise movement of the roll 11 will take place, or vice versa. Likewise, a direction of roll movement may be changed while a closure rim 4 is being pressed against a receptacle wall (inner side 5 and/or outer side 8) of a receptacle 1, so that a rotation of a tool 10 with the roll 11 will take place first in a clockwise direction and, on the same closure 3, subsequently in an anticlockwise direction, or vice versa.
(49) Apart from fastening a closure 3 to a receptacle wall 5, 6 by means of a hot glue or a sealing wax, the closure rim 4 is thermally connected to a receptacle wall 5, 6 according to preferred embodiments of the invention. This may, for example, be done by soldering or welding.
(50) According to a further embodiment, a closure assembly 20 may comprise a counterholder. The counterholder is attached to a side of a receptacle wall on which the roll 11 is not present. If a receptacle 1 is closed by connecting a closure rim 4 to an inner side 5 of the receptacle, the counterholder abuts on the associated outer side 8 of the receptacle. If a closure rim 4 is connected to an outer side 8 of the receptacle, the counterholder abuts on the associated inner side 5 of the receptacle. The counterholder is able to counteract a force, which acts via a roll 11 on a wall of a receptacle 1, whereby a possible deformation of the basic shape of the receptacle 1 can be prevented.