JP2018134664A - Can seaming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce sharp wrinkles in a seaming part thereby obtaining a reliable double-seaming part.SOLUTION: A method for sealing a can drum flange part and a can lid curl part has: an entrainment process in which an entrainment part is formed in such a manner that a can lid and a can drum are held in an axial direction of the can drum, a concave circular arc-shaped sealing rail having a first molding groove on an inner peripheral surface thereof is moved toward a radial direction inner side of the can lid, and the flange part and the curl part are relatively rolled along a circumferential direction in the first molding groove; and a crushing process in which a double-seaming part is formed in such a manner that a seaming roll having a second molding groove on an outer peripheral surface thereof is moved to the entrainment part radial direction inward, and is relatively moved in a circumferential direction of the can lid. A curvature radius of the inner peripheral surface of the sealing rail is four times or less than a curvature radius of an outer peripheral surface of the can lid.SELECTED DRAWING: Figure 1

Description

  TECHNICAL FIELD The present invention relates to a can winding method for sealing a container by double winding an outer peripheral portion of a can lid around an opening end of a can body.

  In a can filled with a soft drink or the like, an outer peripheral portion of a can lid is double-wrapped on an opening end portion of a bottomed cylindrical can body. Such a double winding part of the can, in advance, with the curl part of the can lid covered with the flange part provided at the opening end of the can body, the roll approached from the outside of the can lid, It winds so that a curl part and a flange part may be entangled, and it processes by further crushing the wound part from a radial direction. A compound (resin for sealing) is applied to the inner surface of the curled portion of the can lid, and the compound is sealed by being interposed in the gap between the flange portion of the wound can body and the can lid curled portion. .

As a method of winding such a can, generally, the first winding roll is approached from the outer side in the radial direction while sandwiching and rotating the can body and the can lid placed on the flange portion in the can axis direction. Then, it winds so that the flange part and the curl part of the can lid can be held together (primary winding tightening), and then closes the winding part further inward in the radial direction by bringing the second winding roll closer (secondary winding) By double winding, a double winding part is formed.
In addition to the method of using such a winding roll, winding methods such as Patent Document 1 and Patent Document 2 have also been proposed.

In Patent Document 1, while a can is being conveyed linearly, a predetermined amount of the can is rolled while rolling the can to the linear first, second, and third seaming portions provided on the sides of the conveyance path. It is designed to be tightened.
In Patent Document 2, while a can is conveyed by a turret, temporary winding is performed by an arc-shaped curling rail provided along the conveyance direction on the outer periphery of the turret, and then primary winding and secondary winding are performed by a normal seamer body. Are performed continuously.

JP 2016-97416 A JP 2012-101854 A

By the way, such winding tightening is a process of reducing the diameter of the flange portion of the can body and the curled portion of the can lid, so that wrinkles are likely to occur. When sharp wrinkles (wrinkles with a small radius of curvature) occur, the wrinkle tips may break through the can body during the winding process, causing the contents to leak.
In this case, it is considered that there is a possibility that sharp wrinkles can be reduced by using a linear seaming portion or an arc-shaped curling rail as described in the patent document, but an appropriate method has not yet been reached. .

  This invention is made | formed in view of such a situation, and it aims at reducing the sharp wrinkle of a winding fastening part and obtaining a healthy double winding fastening part.

  The method of winding a can according to the present invention is a method of winding a can barrel flange portion and a can lid curl portion, and sandwiching the can lid and the can barrel in the axial direction of the can barrel, A concave arc-shaped winding rail having a first forming groove on the surface is moved inward in the radial direction of the can lid so that the flange portion and the curl portion are moved in the first forming groove. A winding step in which the winding portion is formed while relatively rolling along the circumferential direction, and a winding roll having a second forming groove on the outer peripheral surface is moved radially inward to the winding portion. A crushing step of forming a double winding portion while rolling relatively in the circumferential direction of the can lid, and the radius of curvature of the inner peripheral surface of the first forming groove in the winding rail is It is not more than 4 times the radius of curvature of the outer peripheral surface.

In the case of the winding method using the winding roll, since the convex arcs of the outer peripheral surface of the roll and the outer peripheral surface of the can lid start to contact at points, the contact range during processing is narrow. On the other hand, in the entrainment process of the present invention, the concave arc-shaped winding rail contacts the outer peripheral surface of the can lid, so that the winding rail contacts the inner peripheral surface of the first forming groove and the outer peripheral surface of the can lid. The front and rear of the part are also close to the outer peripheral surface of the can lid. Then, in this state, by pushing inward in the radial direction of the can lid, the winding rail comes into contact with the can lid within a predetermined range from the center of the press molding to the front and back. While forming gradually from the front position in the moving direction, wrap-around molding is performed at the center of press molding. In other words, wrap-around molding is performed at the center of the press molding while preforming at a position in front of the center of the press molding. On the other hand, even at a position rearward from the center portion of the press molding, the winding portion is gradually separated from the first molding groove of the winding rail, so that inadvertent movement due to the reaction of the winding molding is prevented.
Therefore, the flange part of the can body and the curl part of the can lid are formed by being gradually deformed between the center part of the press molding, and a part of the entrained part after molding is also in the first molding groove. Since it is supported, sharp wrinkles are suppressed.
In this case, if the radius of curvature of the inner peripheral surface of the first forming groove in the winding rail exceeds four times the radius of curvature of the outer peripheral surface of the can lid, preliminary molding at the front position of the center portion of the press molding is not sufficient. The deformation of the can lid and the can body becomes so large that wrinkles cannot be suppressed.

  In the can winding method of the present invention, the radius of curvature of the inner peripheral surface of the first forming groove in the winding rail may be 1.5 times or more the radius of curvature of the outer peripheral surface of the can lid. When the radius of curvature of the outer peripheral surface of the can lid is about 1.5 times the radius of curvature, it is considered easier to handle the winding rail in a ring shape than in a concave arc shape. In addition, it is possible to smoothly move the can lid and the winding rail away from each other.

  ADVANTAGE OF THE INVENTION According to this invention, generation | occurrence | production of the sharp wrinkle of a winding fastening part can be suppressed, and a healthy double winding fastening part can be obtained.

It is a longitudinal cross-sectional view of the principal part which shows the winding method of the can of embodiment of this invention in order of (a) winding-in process and (b) crushing process. It is a longitudinal cross-sectional view of the double winding part wound by the method of FIG. It is a model figure which shows the example of the winding apparatus used for the winding method of this invention by a front view. It is the model figure which planarly viewed the relationship between the winding rail, can lid, and winding roll in FIG. It is a model figure of the winding process by the winding rail in simulation analysis. It is a model figure of the winding process by the normal 1st winding roll in simulation analysis. It is a graph which shows the relationship between the radius of a winding rail, and the generation | occurrence | production state of wrinkles. It is a cross-sectional model figure of the winding part in simulation analysis. It is an analysis figure which shows the mode of the wrinkle of the can lid in the simulation analysis at the time of winding with the normal 1st winding roll and the 2nd winding roll. It is a figure which shows the direction of a wrinkle set by simulation analysis, and the curvature of a wrinkle.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
3 and 4 show a winding device to which the winding method of the present embodiment is applied. In the winding device 40, the can lid 10 provided with the curled portion 14 on the outer peripheral portion is brought into close contact with the flange portion 23 provided in the opening portion of the can body 20, so that the flange portion 23 and the curled portion 14 are held together. It is the device which winds up.

  The can body 20 before being wound is formed by punching an aluminum alloy sheet into a wide-cup shape and then drawing and ironing (DI processing). After coating the outer and inner surfaces, The bottom cylindrical body part 21, the tapered diameter part 21a provided by reducing the diameter of the upper part of the body part 21, and the neck part 22 provided at the upper end of the diameter reduction part 21a are radially outward. It is the shape in which the flange part 23 which spreads is formed (refer FIG. 1). In addition, the plate | board thickness of this flange part 23 shall be 0.16 mm or more and 0.20 mm or less.

On the other hand, the can lid 10 before winding is formed by press-molding a coated aluminum alloy plate material, and the circular panel portion 11 having a smaller diameter than the neck portion 22 of the can body 20 provided at the center portion, and the panel portion. A chuck wall portion 13 is formed by extending upward through a counter sink portion 12 that forms an annular groove on the outer edge of the outer peripheral edge of the belt 11, and an outer peripheral edge curls inward while extending radially outward from the upper end of the chuck wall portion 13. The curled portion 14 is formed (see FIG. 1). In addition, the plate | board thickness of the curl part 14 shall be 0.205 mm or more and 0.225 mm or less. A compound 15 is applied to the inner surface of the curled portion 14.
In the following, the can body 20 and the can lid 10 will be described with the same reference numerals before and after winding.

  The winding device 40 includes a chuck member 41 that abuts against the can lid 10 and presses the can lid 10 that covers the can body 20 from above, a lifter 45 that holds the can body 20 and moves up and down, and the chuck member 41. A canning rail 50 and a tightening roll 60 are provided to perform a tightening process in two stages by approaching the can lid 10 and the can body 20 that are rotated between the lifter 45 and the can body 20 from the outside in the radial direction. .

  The chuck member 41 is formed in a sleeve shape as a whole, and a pressing force applied radially inwardly applied from the winding rail 50 and the winding roll 60 at the time of winding is applied to the chuck of the can lid 10 on the lower outer peripheral surface. A wall portion 43 that is supported inside the wall portion 13 is formed, and an annular projecting portion 42 that is fitted to the counter sink portion 12 of the can lid 10 is formed below the wall portion 43.

The winding rail 50 is formed in a ring shape as a whole, and a first forming groove 51 is formed along the circumferential direction on the inner peripheral portion thereof. In the longitudinal section, the first forming groove 51 is continuous from the upper convex curved surface 52 that is continuous from the upper part of the inner periphery disposed in the upper part in the axial direction, and from the lower part of the inner periphery that is disposed in the lower part of the axial direction. The lower convex curved surface 53 and the concave curved surface 54 between them are formed. The concave curved surface 54 is formed by continuously connecting a plurality of arc surfaces and a part of flat surfaces in the longitudinal section. Moreover, the inner peripheral lower part is arrange | positioned radially outward rather than the inner peripheral upper part.
The first forming groove 51 of the winding rail 50 can have the same profile as the forming groove of the first winding roll that is used in the conventional winding with a normal roll.
The radius of curvature of the ring of the winding rail 50, specifically, the radius of curvature R1 of the deepest part (see FIG. 1A) of the concave curved surface 54 of the first forming groove 51 is the outer peripheral surface of the can lid 10. Is set to be four times or less of the radius of curvature R2.

The winding roll 60 is formed in a cylindrical shape, and a second forming groove 61 is formed along the circumferential direction on the outer peripheral portion thereof. In the longitudinal section, the second forming groove 61 is continuous from the upper convex curved surface 62 that is continuous from the upper part of the inner periphery disposed above the axial direction, and from the lower part of the inner periphery that is disposed downward in the axial direction. The lower convex curved surface 63 and the concave curved surface 64 between them are formed. The concave curved surface 64 is shallower than the concave curved surface 54 of the winding rail 50, and its inner bottom surface is formed with a radius of curvature close to flat. Moreover, the inner peripheral lower part is arrange | positioned radially outward rather than the inner peripheral upper part.
The second forming groove 61 of the winding roll 60 can also have the same profile as the forming groove of the second winding roll used in the conventional winding with a normal roll.
As shown in FIG. 4, the winding roll 60 is arranged on the radially inner side of the winding rail 50, and the center portion (A in FIG. 4) of press molding to the can lid 10 by the winding rail 50. 4), the central portion (position indicated by B in FIG. 4) of the winding roll 60 is located at a position spaced apart in the circumferential direction of the can lid 10, that is, on the opposite side to 180 ° in the illustrated example. Are arranged as follows.

  Then, the curled portion 14 of the can lid 10 is placed on the flange portion 23 of the can body 20, the chuck member 41 is fitted to the can lid 10 from above, and the can is between the chuck member 41 and the lifter 45. The body 20 and the can lid 10 are sandwiched and rotated about the axis X. And the winding process by the winding rail 50 and the crushing process by the winding roll 60 are sequentially performed with respect to the flange portion 23 of the rotating can body 20 and the curled portion 14 of the can lid 10.

In the winding process, as shown in FIG. 1A, the winding rail 50 is approached from the outside in the radial direction, and the curled portion 14 of the can lid 10 and the flange portion 23 of the can body 20 are connected to the first forming groove 51. Of the can lid 10 and the can body 20 so as to roll the can lid 10 and the can body 20 along the surface of the concave curved surface 54. The winding rail 50 is moved in the circumferential direction while synchronizing with the rotation. As a result, the curled portion 14 of the can lid 10 is curled integrally from the outside of the flange portion 23 of the can body 20 while being folded back like a bowl, and a winding portion 71 is formed which is wound so as to tie them together.
In this case, the winding portion 71 is formed by rolling the can body 20 and the can lid 10 several times (for example, 7 rotations) along the winding rail 50.

Next, in the crushing step, as shown in FIG. 1B, the winding roll 60 is radially outwardly moved on the can body 20 and the winding portion 71 of the can lid 10 which are held and rotated by the lifter 45 and the chuck member 41. , The outer peripheral portion of the winding portion 71 is guided to the second forming groove 61 of the winding roll 60 and is pressed radially inward by the concave curved surface 64 to form the wall portion 43 of the chuck member 41. Crush further in the radial direction (thickness direction).
Also in this process, the can body 20 and the can lid 10 are tightened while being rotated, for example, three times while being pressed by the winding roll 60.
The double winding part 72 shown in FIG. 2 is formed by the above winding process and crushing process.

  In this winding method, the winding process performed by the first winding roll in the general winding method using the roll is performed by the winding rail 50, and formed along the inner peripheral surface of the winding rail 50. The first forming groove 51 is processed on the inner surface. Since the first molding groove 51 is formed in a concave arc shape along the inner circumferential surface of the winding rail 50 with respect to the convex arc surface of the outer circumferential surface of the can lid 10, the inner circumference of the first molding groove 51 is The front and back of the contact start portion between the surface and the outer peripheral surface of the can lid 10 are also close to the outer peripheral surface of the can lid 10. Then, in this state, the can lid 10 is pressed inward in the radial direction and molded, whereby the center portion of the press molding (extension of the line connecting the axis C1 of the can lid 10 and the center C2 of the winding rail 50) is performed. The contact portion between the can lid 10 and the winding rail 50 on the line; in the case of FIG. 4, the curled portion 14 of the can lid 10 and the flange portion 23 of the can body 20 from the position a predetermined distance forward from the point A) The first molding groove 51 is guided into the first molding groove 51, and is gradually formed by the first molding groove 51, and is then wound and formed at the center A of the press molding. Further, even at a position behind the center portion of the press molding, the winding portion 71 is not gradually lost from the support by the winding rail 50 and is gradually separated from the first molding groove 51.

  In the case of winding with a conventional general roll, when the first winding roll approaches the can lid and presses from outside in the radial direction, the deformation of the can lid and the can body is concentrated in a part of the circumferential direction. Since there is no support in the front-rear direction, the front-rear position in the circumferential direction of the molding part hardly follows the molding, and as a result, wrinkles are likely to occur.

In the winding method of the present embodiment, the winding rail 50 is in contact with or close to the can lid 10 within a predetermined range before and after the central portion A of the press molding, and therefore, the deformation is prevented from concentrating locally. In addition, the can lid 10 can be supported before and after that, and in particular, since the wrapping is performed while preforming at a position in front of the central portion A of the molding, the generation of sharp wrinkles can be effectively reduced.
In this case, by setting the radius of curvature R1 of the inner peripheral surface of the first forming groove 51 in the winding rail 50 to be four times or less the radius of curvature R2 of the outer peripheral surface of the can lid 10, in front of the center portion A of the press molding. It is possible to sufficiently secure the length of the preforming and the length of the support at the rear, and to reliably reduce the occurrence of sharp wrinkles. The smaller the radius of curvature of the inner peripheral surface of the first forming groove 51 in the winding rail 50, the larger the length of the pre-forming and the length of the support behind the press-molding portion. Since the can lid 10 is disposed on the top, it is necessary to make the radius of curvature more than 1 times the radius of curvature R2 of the can lid 10. The curvature radius R1 of the inner peripheral surface of the first forming groove 51 in the winding rail 50 is preferably 1.5 times or more and 4 times or less the curvature radius R2 of the outer peripheral surface of the can lid 10. If it is 1.5 times or more, the separation between the can lid 10 and the winding rail 50 can be performed smoothly.

  In the next crushing step, as in the conventional case, the winding portion 71 is pressed from the outside in the radial direction by the second forming groove 61 of the winding roll 60 so that the winding portion 71 is crushed and the double winding portion 72 is pressed. Form. In this crushing process, since the entraining portion 71 has already been formed, the amount of deformation is small, and therefore sharp wrinkles are less likely to occur.

In addition, this invention is not limited to the said embodiment, A various change can be added in the range which does not deviate from the meaning of this invention.
For example, although the winding rail 50 is formed in a ring shape in the embodiment, it may be formed in a concave arc shape that is not connected as a ring.
In FIG. 4, the winding roll 60 is arranged on the inner side in the radial direction of the winding rail 50. However, the winding roll 60 is arranged side by side without being placed inside the winding rail 50. It is good also as a structure which performs a process and a crushing process continuously. As shown in FIG. 4, when the winding roll 60 is arranged inside the winding rail 50 in the radial direction, the curvature radius R1 of the inner peripheral surface of the first forming groove 51 is twice the curvature radius R2 of the can lid 10. It is good to have more.
Further, while the can lid 10 and the can body 20 are sandwiched and rotated in the can axis direction, the winding rail 50 and the winding roll 60 are brought close to each other in the radial direction, but the winding rail 50 is fixed in the winding process. And you may make it roll the can lid 10 and the can body 20 along the 1st shaping | molding groove | channel 51 of the inner peripheral part.

The simulation result performed for the effect confirmation by the winding method of this embodiment is demonstrated.
A can lid and a can body having a nominal diameter of 204 (outer diameter of the curl portion of the can lid of 62.15 mm) were used as objects to be wound. The plate thickness of the flange portion of the can body was 0.180 mm, and the plate thickness of the curl portion of the can lid was 0.215 mm.
As winding rails, a plurality of radiuses of curvature of the inner peripheral surface were prepared from 1.5 times to 5 times the curled portion of the can lid, and each was subjected to a winding process. For comparison, a product in which the entrainment process was performed with a normal first winding roll and a linear winding rail were also produced.
FIG. 5 is a model diagram of a winding process using a winding rail, and FIG. 6 is a model diagram of a winding process using a normal first winding roll. However, in FIG. 5, for the sake of convenience, a part of the rail is cut and removed so that the can can be seen.
The simulation was performed using commercially available general-purpose CAE software Abaqus / Explicit. In the analysis, the can body and can lid were modeled using shell elements in order to accurately reproduce bending and wrinkles. At that time, since the contact position with the winding rail or winding roll becomes inaccurate only with the shell element, the membrane element is arranged at the plate thickness position of the can body and the can lid, and the membrane element is combined with the shell element, Each of the can body and the can lid was set to behave as a single plate (see FIG. 8; however, FIGS. 8 to 10 show a normal first winding roll).
FIG. 9 shows the state of wrinkles that occur when analysis is performed with a normal first winding roll. Curvature was used to quantitatively evaluate the wrinkles thus obtained (see FIG. 10). Wrinkles (inward wrinkles) that occur radially inward (p> 0), wrinkles (outward wrinkles) that occur outward in the radial direction (p <0), and wrinkle curvature can All nodes at the top of the lid were investigated.

The analysis result of the simulation is shown in FIG. FIG. 7 shows the first forming of the winding rail when it is wound using a normal first winding roll and when it is wound using the winding rail, and the winding rail is linear. The radius of curvature of the groove is 8.0 times, 4.0 times, 2.0 times, and 1.5 times the radius of curvature of the outer peripheral surface of the can lid. The change in the wrinkle curvature is plotted on the horizontal axis, and the frequency (number of all nodes) is plotted on the vertical axis. A portion where the change in curvature is large indicates that wrinkles have occurred, and a change in curvature of “0” indicates that there are no wrinkles. If the change in curvature is in the range of “−0.05” to “+0.05”, it may be considered that wrinkles have not occurred.
As shown in FIG. 7, wrinkles were not observed when the radius of curvature of the winding rail was 1.5 to 4 times that of the can lid.

DESCRIPTION OF SYMBOLS 10 Can lid 20 Can body 11 Panel part 12 Counter sink part 13 Chuck wall part 14 Curl part 15 Compound 21 Body part 21a Diameter reduction part 22 Neck part 23 Flange part 40 Tightening device 41 Chuck member 42 Annular protrusion part 43 Wall part 45 Lifter 50 Winding rail 51 First forming groove 52, 62 Upper convex curved surface 53, 63 Lower convex curved surface 54, 64 Concave curved surface 60 Winding roll 61 Second forming groove 71 Winding part 72 Double winding part

Claims (2)

  A method of winding a can barrel flange portion and a can lid curl portion, wherein the can lid and the can barrel are sandwiched in the axial direction of the can barrel, and a concave circle having a first forming groove on an inner peripheral surface An arc-shaped winding rail is moved inward in the radial direction of the can lid, and the flange portion and the curl portion are relatively rotated along the circumferential direction of the winding rail in the first forming groove. A winding step for forming the winding portion while moving the winding roll, and a winding roll having a second forming groove on the outer peripheral surface is moved radially inward to the winding portion to relatively rotate in the circumferential direction of the can lid. A crushing step of forming a double winding portion while moving, and the radius of curvature of the inner peripheral surface of the first forming groove in the winding rail is not more than four times the radius of curvature of the outer peripheral surface of the can lid A method of winding a can characterized by being.   The can winding method according to claim 1, wherein the radius of curvature of the inner peripheral surface of the first forming groove in the winding rail is 1.5 times or more of the radius of curvature of the outer peripheral surface of the can lid. .