SEAMING SHAFT ARRANGEMENT FOR A SEALER

Abstract

A seaming shaft arrangement for a sealer for attaching a can lid to a can body. The seaming shaft arrangement includes a seaming head, an ejection rod, an ejection head arranged on the ejection rod and movable with the ejection rod relative to the seaming, and a spring assembly by which the ejection head is resiliently mounted on the ejection rod. The spring assembly includes a slider arranged movably in the axial direction on the ejection rod, and a first elastic element arranged between a first abutment surface of the slider and a first supporting surface of the ejection rod, and a second elastic element arranged between a second abutment surface of the slider and a second supporting surface of the ejection head.

Claims

1. A seaming shaft arrangement for a sealer for attaching a can lid to a can body comprising: a seaming head configured to fix the can lid to the can body; and an ejection rod; and an ejection head arranged on the ejection rod and movable with the ejection rod relative to the seaming head in an axial direction of the ejection rod; a spring assembly by which the ejection head is resiliently mounted on the ejection rod, and comprising a slider arranged movably in the axial direction on the ejection rod, and a first elastic element arranged between a first abutment surface of the slider and a first supporting surface of the ejection rod, and a second elastic element arranged between a second abutment surface of the slider and a second supporting surface of the ejection head, and the slider being configured to be supported on the ejection head such that the ejection head is resiliently mounted on the ejection rod via the first elastic element.

2. The seaming shaft arrangement according to claim 1, wherein the slider is configured to be supported on the ejection head such that the ejection head is resiliently mounted on the ejection rod exclusively via the first elastic element.

3. The seaming shaft arrangement according to claim 1, wherein the slider is a sleeve which is arranged around the second elastic element.

4. The seaming shaft arrangement according to claim 1, wherein the slider is a sleeve which is arranged between the second elastic element and the ejection rod.

5. The seaming shaft arrangement according to claim 4, wherein the ejection rod comprises a preload sleeve attached to the ejection rod and comprises a projection by which a path of the slider in the axial direction is delimited via the preload sleeve.

6. The seaming shaft arrangement according to claim 1, wherein the first supporting surface is a step.

7. The A-seaming shaft arrangement according to claim 1, wherein the ejection head comprises an attachment element and an ejection element, and the ejection element via the attachment element.

8. The seaming shaft arrangement according to claim 7, wherein the attachment element comprises an attachment jacket arranged around the ejection rod, the slider, the first elastic element and the second elastic element, and the attachment jacket comprises a projection on which the slider is configured to be supported such that the ejection head is resiliently mounted on the ejection rod via the first elastic element.

9. The seaming shaft arrangement according to claim 7, wherein the attachment element is attached to the ejection rod.

10. The seaming shaft arrangement according to anyone of the claim 7, wherein the ejection element is rotatably arranged about an axis of rotation extending along the axial direction opposite the attachment element.

11. The seaming shaft arrangement according to claim 7, wherein the ejection element is firmly connected or screwed or clamped to the attachment element.

12. The seaming shaft arrangement according to claim 7, wherein the attachment element is movably arranged in the axial direction on a sliding bush arranged on the ejection rod.

13. The seaming shaft arrangement according to claim 1, wherein the first elastic element is a first spring or the second elastic element is a second spring.

14. The seaming shaft arrangement according to claim 1, wherein the first elastic element is configured to transmit a first spring force of 70-160 N to the ejection head, and the second elastic element is configured to transmit a second spring force of 5-30 N to the ejection head.

15. The seaming station comprising a seaming shaft arrangement according to claim 1, further comprising a first seaming roller and a second seaming roller to attach the can lid to the can body.

16. The seaming station according to claim 15, further comprising a lifting element, and the lifting element and the seaming head are configured to have the can body with the can lid arranged therebetween during a seaming process.

17. A sealer comprising: a carousel having the seaming shaft arrangement according to claim 1; a first infeed to feed can bodies to the carousel; a second infeed to feed can lids to the carousel; and an outlet for seamed cans from the carousel.

18. A method for attaching a can lid to a can body, comprising: providing a seaming shaft arrangement according to claim 1; feeding the can lid and the can body to the seaming shaft arrangement; positioning the can lid on the can body; positioning the can body on a lifting element; exerting a spring force on the can lid with the ejection head; seaming the can lid to the can body by at least one seaming roller and the seaming head; synchronous lowering of the ejection head and the lifting element while maintaining the spring force on the can lid; lifting of the ejection head from the can lid; and discharging the seamed can from the seaming shaft arrangement.

19. The method according to claim 18, wherein the can lid is guided by a second spring force in a region of a lid guide and is guided onto the can body, the can body and the can lid are lifted by the lifting element and, during lifting, a first spring force is exerted on the can lid by the ejection head, and during lifting, the first spring force is exerted on the can lid by supporting the slider on the ejection head such that the ejection head is resiliently mounted on the ejection rod via the first elastic element.

20. A spring assembly for a seaming shaft arrangement according to claim 1 comprising: the slider, and the first elastic element arranged at the first abutment surface and the second elastic element arranged on the second abutment surface of the slider.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In the following, the disclosure and the state of the art are explained in more detail on the basis of embodiments with reference to the drawings.

[0045] FIG. 1 is a plan view of a sealer according to the disclosure;

[0046] FIG. 2 is a side view of a seaming station,

[0047] FIG. 3A is a sectional representation of a first embodiment of a seaming shaft arrangement according to the disclosure under the action of a second elastic element;

[0048] FIG. 3B is a further sectional representation of the embodiment according to FIG. 3A under the action of a first elastic element;

[0049] FIG. 4 is an exploded view of an ejection head according to the disclosure, in which a spring assembly according to the disclosure is additionally represented;

[0050] FIG. 5 is a schematic representation of a second embodiment of a seaming shaft arrangement according to the disclosure.

DETAILED DESCRIPTION

[0051] FIG. 1 shows a plan view of a sealer 1000 according to the disclosure.

[0052] The sealer 1000 for sealing a can comprises a lid feeder 11 for feeding a can lid 101 to a can body 100, a gassing rotor 15 for feeding gas to the can body 100, and a seaming station 14 for sealing the can body 100 with the can lid 101.

[0053] In the operating state, the can lid 101 is introduced along the arrow C through the lid feeder 11 into the sealer 1000. In this case, the can lids 101 are arranged on the gassing rotor 15. The can lids 101 are transported further by rotation of the gassing rotor 15. Then, the can bodies 100 are introduced into the container receptacles 17 of the gassing rotor 15 by the container feeder 12. There, the can body 100 is gassed with a gas such as carbon dioxide or nitrogen in area D and is united with the can lid 101.

[0054] The gassing is carried out along the arrow B with the gas supply 16. After gassing, the can body 100 with the cover 101 is further transported through the container discharge 13 from the gassing rotor 15 to the seaming station 14 and is sealed there.

[0055] Before the actual seaming process, can lid 101 and can body 100 are united as described above. The can bodies 100 are fed linearly via the container feeder 12. The can bodies pass from the container feeder 12 onto one of the respective lifting elements 22 of the seaming station 14, which is designed as a carousel (preferably arranged in the form of a vertical shaft). During one rotation of the carousel, the lifting elements 22 perform a cam-controlled lifting movement, whereby the can bodies 100 are guided from below against the can lids 101. After a certain stroke distance, the can body 100 and the can lid 101 touch each other.

[0056] To enable the remainder of the stroke to be performed together without interference, an ejection head according to the disclosure (not shown here), is used to clamp the can body 100 and can lid 101.

[0057] FIG. 2 shows a side view of a seaming station 14 according to the disclosure with a can body 100 to be sealed and a can lid 101.

[0058] According to FIG. 2, the seaming station 14 comprises a clamping device which comprises the lifting element 22 and a seaming head 2, whereby the seaming head 2 is attached via the seaming shaft 3. In addition, the seaming station 14 comprises at least one seaming roller 10 with a seaming roller profile 111 which is rotatably mounted via a roller shaft 3A. The can lid 101 is arranged centered above the opening of the can body 100. The can body 100 has a circumferential can flange in the region of the can opening, and the can lid 101 has a circumferential can lid flange.

[0059] During the sealing process, the seaming roller 10 is brought into contact with the can flange and the can lid flange via the seaming roller profile 111. Here, the can flange and the can lid flange are pressed together via the seaming roller 10 by a force acting substantially radially. The pressing is achieved by a continuous rolling of the seaming roller 10 in the circumferential direction along the circumference of the can opening.

[0060] For sealing, the can body 100 is rotated by the clamping device by rotating the seaming head 2 with the seaming shaft 3 about the seaming axis X (corresponds to an axial direction).

[0061] FIGS. 3A and 3B show sectional representations of a first embodiment of a seaming shaft arrangement 1 according to the disclosure.

[0062] The seaming shaft arrangement 1 comprises the seaming head 2, which is arranged on the seaming shaft 3, and an ejection rod 3, and the ejection head 4 arranged on the ejection rod 3 and movable with the ejection rod 3 relative to the seaming head 2 (and the seaming shaft 3) in an axial direction X of the ejection rod 3. The ejection rod 3 is movably arranged substantially inside the seaming head 2 (and seaming shaft 3).

[0063] The seaming shaft arrangement 1 further comprises a spring assembly 5 by which the ejection head 4 is resiliently mounted on the ejection rod 3.

[0064] The spring assembly 5 comprises a slider 6 arranged movably in the axial direction X on the ejection rod 3, and a first elastic element 51 arranged between a first abutment surface 61 of the slider 6 and a first supporting surface 31 of the ejection rod 3. In addition, the spring assembly 5 comprises a second elastic element 52 arranged between a second abutment surface 62 of the slider 6 and a second supporting surface 42 of the ejection head 4.

[0065] According to the disclosure, the slider 6 can be supported on the ejection head 4 in such a way (in an operating state) that the ejection head 4 is resiliently mounted on the ejection rod 3 exclusively via the first elastic element 51.

[0066] In the embodiment shown, the first elastic element 51 is a first spiral spring 51 and the second elastic element 52 is a second spiral spring 52.

[0067] The ejection head 4 comprises an attachment element 43 and an ejection element 41, which form an integral part. The ejection head 4 is movably arranged on the ejection rod 3 via the attachment element 43 (attachment not shown here).

[0068] The attachment element 43 has a jacket 45 which is arranged around the ejection rod 3, the slider 6, the first spiral spring 51 and the second spiral spring 52. The jacket 45 has a projection 44 directed towards the ejection rod 3, on which the slider 6 can be supported (on a slider supporting surface). This means that this projection 44 comprises the slider supporting surface. In this way, it is made possible that the ejection head 4 is resiliently mounted on the ejection rod 3 via the first spiral spring 51, since a force transmission between the first spiral spring 51 and the ejection element 41 takes place via the slider 6.

[0069] In this way, a staggered force transmission is possible, since when the can 100, 101 is approached, first a second spring force of 10-20 N (to hold the can lid 101 in a lid guide) is exerted by the second spiral spring 52, and then to fix the can lid 101 centered on the can body 100, a first spring force of 80-150 N can be exerted by the first spiral spring 51. Thus, the can lid 101 is held centered on the can body 100 by a defined, uniform force when it is raised to the seaming head 2, so that any buckling can be avoided when it is moved into the seaming head 2.

[0070] FIG. 3A shows the can lid 101 as it is held in a lid guide not shown. The lid 101 is applied with the second spring force of the second spring 52 by the ejection element 41. In this way, the lid 101 can be centered on the can body 100.

[0071] As soon as the can body 101 is introduced into the can lid 100, the ejection head 4 changes the direction of the stroke and moves upward uniformly with the lifting element (under the can 100, 101, not shown), whereby the can lid 101 is fixed centered on the can body 100 by the first force of the first elastic spring 51. For this purpose, the lid 101 is exclusively applied with the first spring force of the first spring 51 by the ejection element 41 and can thus enter the seaming head 2 centered with the can body 100. To ensure that only the first spring force acts, the slider 6 is supported on the projection 44 of the ejection head 4.

[0072] FIG. 3B shows the can lid 101 as it is arranged centered on the can body 100 and in engagement with the seaming head 2. From this moment on, the can 100, 101 is clamped between the lifting element (not shown) and the seaming head 2. Subsequently, the actual seaming process is carried out.

[0073] FIG. 4 shows an exploded view of the individual elements of the ejection head 4 according to the disclosure according to FIGS. 3A and B, in which the spring assembly according to the disclosure is represented in addition to the ejection head 4. However, the ejection head 4 is not shown in its entirety, as parts at the lower end, such as the ejection element, are not shown.

[0074] The first abutment surface 61 of the slider 6 and the second abutment surface 62 of the slider 6 are located on opposite sides of a circumferential ring of the slider 6.

[0075] An O-ring seals a joint between the ejection element 41 and the attachment element 43. A sliding bush (or sliding bearing) 92 is attached with a screw 8.

[0076] Thus, the attachment element 43 is not screwed tightly to the ejection rod 3 but is arranged movably thereon (via the sliding bush 92 which is delimited at the top as well as at the bottom, respectively at two sides with reference to the axial direction X, respectively). The movement of the attachment element 43 on the ejection rod 3 is delimited by the preload sleeve 7 and the screw 8. Thus, the attachment element 43 slides on the sliding bush 92.

[0077] On a sliding surface of the sliding bush 92, the attachment element can travel the entire spring travel (of the first and second elastic elements). This sliding surface is delimited by the screw 8 on a first side and by the preload sleeve 7 on the other side.

[0078] The first supporting surface is located on the disk 310, which is supported on a step 311 of the ejection rod as shown in FIG. 3.

[0079] FIG. 5 shows a schematic representation of a second embodiment of a seaming shaft arrangement 1 according to the disclosure. Basically, the structure is analogous to the seaming shaft arrangement according to FIGS. 3A and B, but the slider 6 is a sleeve 6 which is arranged around the second spiral spring 52 and can transmit the first spring force directly to the ejection head 4 arranged movably on the ejection rod 3. The force transmission from the first spring 51 can take place when the sleeve 6 completely encloses the second spring 52 and is supported on the ejection element 41.