JP6342307B2 - Can winding method, first winding roll and can winding device - Google Patents

Description

  The present invention relates to a can winding method in which the outer periphery of a can lid is double-wrapped to an opening end of a can body to seal the inside of the can, a first winding roll used in the can winding method, The present invention relates to a can winding device.

  For example, a can used for a container such as a soft drink is formed by double winding an outer peripheral portion of a can lid on an opening of a bottomed cylindrical can body. In such double winding of the can, the flange portion provided in advance in the opening of the can body is covered with the curled portion provided in the outer peripheral portion of the can lid, and the curled portion and the flange portion are attached. It is performed by processing so that it may be wound together.

  In this way, as a can tightening device that double-tightens the can lid and the can body, a chuck member that comes into contact with the can lid, and a lifter that holds the can body and moves up and down in the axial direction thereof. And a first winding tightening roll (first seaming roll) that is slidably brought into contact with the rotating can lid and the can body sandwiched between the chuck member and the lifter from the outside in the radial direction and entangled with the flange portion and the curled portion. Roll) and a second winding roll (second seaming roll) that presses the winding portion of the flange portion and the curl portion further inward in the radial direction to form a double winding portion (second seaming roll). It has been known.

In this can winding apparatus, the first winding roll is rotatably supported, and when winding the flange portion of the can body and the curled portion of the can lid, When the forming concave portion (groove portion) of the first winding roll abuts, the first winding roll is also rotated by friction.
Thus, at the start of winding by the first winding roll, since the stationary first winding roll comes into contact with the rotating can lid, the rotation speed of the can lid and the first winding roll is not constant. However, a difference occurs in the rotation speed. Therefore, when the edge of the curled portion and the molding concave portion of the first winding roll abut at the start of winding, the tip of the curled portion is scraped and thin chips are likely to be generated.

As a countermeasure against this thin chip, Patent Document 1 proposes that the curl portion (peripheral portion) of the can lid is formed so that the wall thickness becomes thinner toward the end edge side. When the edge of the part comes into contact with the forming recess (groove) of the first winding roll, it bends easily, and the curved surface in the middle of the curled part replaces the end edge. It is described that it can be wound up without being caused by generating thin chips.
In addition, in order to avoid the edge of the curled portion coming into contact with the molding recess at the start of winding, the contact start position between the curling portion and the molding recess is not the tip side of the curled portion of the can lid, but the curling portion. Increasing use is being made of can winding devices with a medium curved surface.

Japanese Patent Laid-Open No. 9-20334

  However, in recent years, in order to reduce the weight of the can lid, it has been studied to reduce the thickness of the can lid material. For this reason, like the can lid described in Patent Document 1, there is a limit to reducing the thickness of the edge of the curled portion, and it is difficult to suppress the generation of thin chips. In addition to reducing the thickness of the can lid material, it has been studied to reduce the length in the radial direction (curl width) from the maximum outer peripheral position of the curled portion to the tip as compared with the conventional method. In the apparatus, it is difficult to prevent the generation of thin chips and to sufficiently wind up the curled portion.

  The present invention has been made in view of such circumstances, and prevents the generation of thin chips when the can lid and the can body are tightened, and maintains the curling of the curled portion to ensure good sealing performance. An object of the present invention is to provide a can winding method, a first winding roll used in the can winding method, and a can winding device.

When the curl width of the curled part is made smaller than before, the edge of the curled part is likely to come into contact with the molding recess of the first winding roll, and the tip is scraped off, so that thin chips are easily generated. For this reason, this inventor makes shallow the depth (groove depth) of the shaping | molding recessed part of a 1st winding tightening roll, and avoids that the edge of a curl part contacts a shaping | molding recessed part at the time of a winding start. In this case, the curl portion cannot be sufficiently wound up, resulting in another problem. Therefore, in order to improve the curling property of the curled portion, it has been considered to reduce the width of the molding recess (groove width) than before. However, if the width of the molding recess is made too small, the tip of the flange portion will enter too much, causing damage to the curled portion and causing local distortion. It has been found that there is a risk of cracking.
In view of such circumstances, the present inventor has taken the following solution.

  The present invention is a method of tightly winding a can lid provided with a curled portion wound inward in the radial direction by tightly contacting a flange portion provided at an opening of the can barrel, the can lid and the can barrel Is clamped in the axial direction of the can body and rotated around the axial center, and from the outside in the radial direction, the first winding roll is brought into sliding contact with the flange portion and the curl portion. A winding step for processing the portion, and a crushing for processing the double winding portion by pressing the flange portion and the curl portion processed by the winding step toward the inside in the radial direction using a second winding roll The first winding roll has, on its outer peripheral surface, an upper jaw part located on the axially upper side of the first winding roll, and a lower jaw part located on the lower side in the axial direction, Outside the entrainment part between the upper jaw part and the lower jaw part A molding recess for molding a surface is formed along the circumferential direction, and the molding recess has a shape in which a plurality of arcuate surfaces and linear portions are continuously connected in order from the upper jaw portion to the lower jaw portion, In the cross section along the axis of the first winding roll, the straight portion is a tangent line connecting the lowermost arc surface in the molding recess and the arc surface of the lower jaw, At the start of contact between the curled portion and the molding recess, a contact start position between the curled portion and the molding recess is provided on the outer peripheral surface in the middle of the curled portion, and the end of the outer peripheral surface tip of the curled portion An edge is provided on the radially outer side of the first winding roll with respect to the outer peripheral edge of the linear portion, and is provided on the radially inner side of the first winding roll with respect to the maximum outer peripheral position of the lower jaw. .

In the conventional first winding roll, the contact start position between the curl portion and the molding recess is radially inward from the maximum outer peripheral position of the lower jaw portion. In this respect, the curl width CD (the length in the radial direction from the maximum outer peripheral position of the curl portion to the tip) is reduced, while the groove width GL (the width of the molding recess) and the groove depth GD (the molding recess) are reduced. If the processing is performed using the conventional first winding roll without changing the depth), the curl portion penetrates deeply into the molding recess, and the contact start position between the curl portion and the molding recess is more than conventional. Is also arranged to enter the bottom side (inside in the radial direction) of the molding recess. For this reason, when the curling of the curled portion proceeds, the tip of the curled portion comes into contact with the lower jaw portion, so that the tip of the curled portion is scraped off and thin chips are easily generated. Further, if the groove depth GD (depth of the molding concave portion) is simply reduced to cope with it, it is difficult to sufficiently wind up the curled portion. As a result, it becomes difficult to ensure a sufficient sealing property of the can, for example, it is difficult to ensure a sufficient dimension of the cover hook or a reverse wrinkle occurs.
Therefore, in the method of the present invention, first, at the start of contact between the curled portion and the molding concave portion, the contact start position between the curled portion and the molding concave portion is set to the outer peripheral surface in the middle of the curled portion, thereby At the start of contact with the molding recess, the tip of the curled portion is prevented from contacting the molding recess. In addition, the first winding roll used in this method has a shape in which the arc surface of the molding concave portion and the arc surface of the lower jaw portion are connected by a straight portion, and is formed with the middle outer peripheral surface of the curl portion. At the start of contact with the recess, the edge at the tip of the outer peripheral surface of the curl portion is more radial than the outer periphery side edge (the connection point between the molding recess and the lower jaw) of the straight portion disposed on the lower end side of the molding recess The outer side and the innermost radial position of the lower jaw are arranged on the inner side in the radial direction. As a result, it is possible to solve the problems of lowering the winding property and reverse wrinkle caused by reducing the curl width CD of the curled part, and at the start of contact between the curled part and the molded concave part, the tip of the curled part and the molded part. Generation of thin chips due to contact with the recesses can be prevented.
In addition, in the configuration in which the straight portion of the molding recess is eliminated and the arc surface of the molding recess and the arc surface of the lower jaw are directly connected, the curling property of the curl portion is deteriorated and it is difficult to ensure the sealing performance of the can. .

In the winding step of the can winding method according to the present invention, the contact start position may be disposed radially inside the first winding roll with respect to the maximum outer peripheral position of the lower jaw.
When the contact start position between the curled part and the molding recessed part is arranged radially outside the maximum outer peripheral position of the lower jaw by disposing the curl part and the forming outer periphery of the lower jaw part radially inward of the first winding roll. Compared to the above, it becomes easy to smoothly guide the outer peripheral surface of the curled portion along the shape of the arc surface of the molding recess. Therefore, the entrainment part can be processed into a stable shape, and good sealing performance of the can can be ensured.

  The first winding roll of the present invention is formed when a can lid provided with a curled portion that is rewound radially inward is brought into close contact with a flange portion provided in an opening of a can body to be wound and molded. The can lid has a curl height of 2.0 mm or more and 2.4 mm or less, which is a distance in a direction parallel to the axis of the can lid of the curl portion, and a maximum outer periphery of the curl portion The curl width CD, which is the radial length from the position to the tip, is formed to be 0.7 mm or more and 1.0 mm or less, and is in sliding contact with the can lid and the can body from the outside in the radial direction. A first winding roll that winds the flange portion and the curl portion to process the winding portion, and an upper jaw portion that is positioned on the upper side in the axial direction of the first winding roll on the outer peripheral surface, and the axial center Between the lower jaw located on the lower side of the direction, and the upper jaw and the lower jaw A molding concave portion for molding the outer peripheral surface of the winding portion is formed along the circumferential direction, and the molding concave portion continuously connects a plurality of arcuate surfaces and linear portions in order from the upper jaw portion to the lower jaw portion. The straight portion is a tangent line connecting a circular arc surface located in the lowermost part of the molding recess and a circular arc surface of the lower jaw in a cross section along the axis of the first winding roll. From the intersection P3 of the perpendicular line Z drawn parallel to the axial center of the first winding roll from the maximum outer peripheral position of the lower jaw part and the imaginary line I extending the linear part radially outward, the perpendicular line Z and The groove width GL of the axial distance to the intersection P1 with the molding recess is 1.9 mm or more and 2.2 mm or less, and the groove depth GD of the radial distance from the perpendicular Z to the deepest position of the molding recess. 1.0mm to 1.3mm Provided, the radial distance from the outer peripheral side edge of the linear portion to the deepest position of the molding recess is A, and the radial length of the linear portion is L, the diameter with respect to the radial distance A The ratio (L / A) of the direction length L is set to 0.09 or more and 0.33 or less.

In this way, in the first winding tightening roll in which measures are taken to set the groove depth GD shallow and the groove width GL small, when the can lid with the curled width CD of the curled portion is tightened, By making the contact start position with the molding recess not the tip of the curled part, but the curved surface in the middle of the curled part, it is possible to reliably obtain a frictional resistance compared to the case of contacting at the tip of the curled part, The curled portion is smoothly wound up along the arc surface of the molding recess. Further, when the curling of the curled portion proceeds, the curled portion is wound up along the circular arc surface and the straight line portion located below the forming concave portion. When attention is paid to the lower surface in the molding recess, the ratio (L / A) between the radial distance A of the molding recess and the radial length L of the linear portion is 0.09 or more and 0.33 or less. Thus, by adjusting the arrangement and size of the linear portion with respect to the arc surface of the molding recess, excessive curling of the curled portion and insufficient curling of the curled portion can be prevented, and the curled width CD of the curled portion can be reduced. Thus, it is possible to solve the problem of the lowering of winding property and the occurrence of reverse wrinkle. Further, since the contact between the tip of the curled portion and the molding concave portion is avoided at the start of contact between the curled portion and the molding concave portion, generation of thin chips can be reliably prevented.
If the ratio (L / A) is less than 0.09, the roll-up property is lowered, and it becomes difficult to obtain sufficient sealing performance of the can. Moreover, when the ratio (L / A) exceeds 0.33, generation of thin chips cannot be prevented.

In the first winding roll of the present invention, the straight portion has an angle β with respect to an orthogonal line H orthogonal to the axis of the first winding roll in a cross section along the axis of the first winding roll. The angle β is provided in the range of −3 ° to 5 °.
The angle β is negative (−: minus) when tilted toward the upper side (upper jaw side) in the axial direction as it goes outward in the radial direction of the first winding roll, and lower in the axial direction ( The case of inclining toward the lower jaw side) is positive (+: plus). And, by providing the straight portion at an angle β of −3 ° or more and 5 ° or less with respect to the orthogonal line H, the outer peripheral surface of the curled portion can be smoothly guided along the straight portion, and the winding property is improved. Can do.
In addition, when the angle β is smaller than −3 °, when the first winding roll is released from the winding portion after the winding portion is processed, the winding portion and the lower jaw portion are easily caught, and the can lid is attached to the can lid. There is a risk that paint scum may be generated by scratching or scraping off the part. On the other hand, when the angle β is larger than 5 °, the windability is deteriorated, and reverse wrinkle is likely to be generated.

  The can winding device according to the present invention is a can that forms a can by tightly winding a can lid provided with a curled portion wound inward in the radial direction, tightly contacting a flange portion provided at an opening of the can body The can lid has a curl height CL, which is a distance in a direction parallel to the axis of the can lid of the curled portion, of 2.0 mm or more and 2.4 mm or less. The curl width CD, which is the length in the radial direction from the maximum outer peripheral position to the tip, is formed to be 0.7 mm or more and 1.0 mm or less, and holds the chuck member that comes into contact with the can lid and the can body Then, a lifter that moves up and down in the axial direction, and a can lid and a can body that are sandwiched in the axial direction by the chuck member and the lifter and rotate around the axial center are slidably contacted from outside in the radial direction. The flange part and the curl part The second winding for processing the double winding portion by pressing the first winding roll to be processed, the flange portion and the curl portion wound by the first winding roll further radially inward. The first winding roll is provided so as to be rotatable about its axial center, and an upper jaw portion positioned on the upper side in the axial direction of the first winding roll; A lower jaw portion positioned on the lower side in the axial direction, and a molding concave portion for molding an outer peripheral surface of the winding portion between the upper jaw portion and the lower jaw portion are formed along a circumferential direction, and the molding concave portion A plurality of arcuate surfaces and straight portions are successively connected in order from the upper jaw portion to the lower jaw portion, and the straight portion is formed in the cross section along the axis of the first winding roll. The lowest circular arc surface in the recess and the front An imaginary line that is a tangent line connecting the arc surface of the lower jaw and extends perpendicularly outward from the perpendicular Z drawn in parallel to the axis of the first winding roll from the maximum outer peripheral position of the lower jaw and the linear portion The groove width GL of the axial distance from the intersection P3 with I to the intersection P1 between the perpendicular Z and the molding recess is 1.9 mm to 2.2 mm, and the deepest of the molding recess from the perpendicular Z The groove depth GD of the radial distance to the position is set to 1.0 mm or more and 1.3 mm or less, the radial distance from the outer peripheral side edge of the linear portion to the deepest position of the molding recess is A, and the straight line When the length in the radial direction of the portion is L, the ratio (L / A) of the radial length L to the radial distance A is set to 0.09 or more and 0.33 or less.

  Further, in the can winding apparatus according to the present invention, the linear portion of the first winding roll is orthogonal to the axis of the first winding roll in a cross section along the axis of the first winding roll. An angle β is provided with respect to the orthogonal line H, and the angle β is provided in a range of −3 ° to 5 °.

  According to the present invention, at the time of winding the can lid and the can body, it is possible to prevent the generation of thin chips, and to solve the problems of lowering the winding property and reverse wrinkle caused by reducing the curl width of the curled portion. It is possible to ensure good sealing performance.

It is sectional drawing along the axial center direction of the can explaining the winding by the 1st winding roll of one Embodiment of this invention, (a) is a contact start time of a 1st winding roll and a can lid, (b ) Shows the point in time when the first winding roll is rotated once. It is sectional drawing along the axial direction explaining the winding by the 2nd winding roll after forming a winding part. It is sectional drawing along the axial center direction of the can body of a double winding part. It is principal part sectional drawing which shows the shaping | molding recessed part periphery of a 1st winding roll. It is the front view which showed roughly a set of winding unit in the winding device of the can of embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The can winding device 100 according to the present embodiment shown in FIG. 5 closely contacts the can lid 10 having the curled portion 14 rewound radially inward to the flange portion 23 provided in the opening of the can body 20. 3 is a device for forming a can by being wound and, as shown in FIG. 3, a double winding structure in which the periphery of the can lid 10 is entangled with the open end of the can body 20 Form.

  FIG. 5 shows the can lid 10 and the can body 20 before double winding. The can body 20 before being rolled is formed by punching an aluminum alloy plate material into a wide-mouthed cup shape, and then further drawing and ironing (DI processing). A straight bottomed cylindrical body portion 21 and a body A tapered reduced diameter portion 21a provided by reducing the diameter of the upper portion of the portion 21 and a flange portion 23 extending outward in the radial direction via a neck portion 22 provided at the upper end of the reduced diameter portion 21a are formed. Shape. 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 being tightened is formed by press-molding an aluminum alloy plate material, and has a circular panel portion 11 having a smaller diameter than the neck portion 22 of the can body 20 provided in the center, and the panel portion 11. A chuck wall portion 13 that extends upward through a counter sink portion 12 that forms an annular groove on the outer edge, and an outer peripheral edge curled inward while extending radially outward from the upper end of the chuck wall portion 13. The curled portion 14 is formed. In addition, the plate | board thickness of the curl part 14 shall be 0.205 mm or more and 0.225 mm or less. Although not shown, a compound is applied to the inner surface of the curled portion 14.

  For example, in the present embodiment, a can lid 10 having a nominal diameter of 204 is used, and this can lid 10 has a curl height CL (parallel to the axis X of the can lid 10) of the curled portion 14 shown in FIG. The distance in the directional direction) is 2.0 mm or more and 2.4 mm or less, and the radial length CD (in other words, the curl width CD) from the maximum outer peripheral position of the curled portion 14 to the tip is 0.7 mm or more and 1.0 mm or less. The plate thickness is 0.205 mm or more and 0.225 mm or less. In particular, the can lid used to make the double winding portion small for the purpose of reducing the weight of the can lid is provided with a curl width CD as short as 0.7 mm or more and 0.85 mm or less, resulting in poor roll-up performance. Therefore, the first winding roll 50 of the present invention, which will be described later, is effective for improving this winding property.

  A can winding device 100 for winding the can lid 10 and the can body 20 is not shown in the figure, but the winding unit 30 shown in FIG. A plurality of sets are provided at intervals, and the can lid 10 and the can body 20 are received while being moved in the circumferential direction by turning the turret, and the flange portion of the can body 20 is sandwiched therebetween. 23 and the curled portion 14 of the can lid 10 are wound.

  The winding unit 30 includes a chuck member 41 that abuts 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 first winding roll 50 and a second winding roll 60 that are slidably brought into contact with the can lid 10 and the can body 20 that are rotated between the lifter 45 and the outer side in the radial direction to perform the fastening process. Prepare.

  The lifter 45 includes a lifter plate 46 on which the can body 1 is placed, and a holder portion 47 that holds a spring or the like that biases the lifter plate 46 upward, and rotates together with the turret of the winding machine body. Thus, while moving along a ring-shaped cam (not shown) fixed to the winding machine body, it moves up and down as shown by arrow A in FIG. 5, and around its own axis X as shown by arrow B1. It is a structure which can be rotationally driven.

The chuck member 41 is disposed on the same axis X as the lifter 45, and is formed in a sleeve shape as a whole. Further, on the outer peripheral surface of the lower part of the chuck member 41, a pressing force applied inward in the radial direction applied from the first winding roll 50 and the second winding roll 60 during winding is applied to the chuck wall portion 13 of the can lid 10. The wall surface 43 that is supported on the inner side of the chuck member 10 is formed so as to incline in a direction in which the diameter gradually increases as it goes upward with respect to the axis X of the chuck member 41. An annular projecting portion 42 that fits the counter sink portion 12 is formed. The upper portion of the chuck member 41 is rotatably supported by the turret of the winding machine body, and the pinion gear engages with the rack of the winding machine body as the turret turns, and is indicated by an arrow B2. In this way, it is driven to rotate.
The chuck member 41 and the lifter 45 are rotationally driven around the axis X in synchronization.

  The first winding roll 50 and the second winding roll 60 have molding recesses 53 and 63 formed on the outer circumferential surface along the circumferential direction, and have a radius as shown by arrows E and F in FIG. On the flange portion 23 of the can body 20 which is spaced apart and approached in the direction and is rotatably supported around its own axis Y1, Y2 and sandwiched between the lifter 45 and the chuck member 41 and rotated. The curl portion 14 of the can lid 10 is sequentially wound from the outside in the radial direction to be tightened while being molded.

The first winding roll 50 is brought into sliding contact with the can lid 10 and the can body 20 sandwiched between the chuck member 41 and the lifter 45 from the outside in the radial direction thereof, so that the curl portion 14 of the can lid 10 and The winding part 15 (refer FIG. 2) which wound the flange part 23 of the can body 20 to radial direction outward is processed.
The first winding roll 50 has a substantially disk shape and is supported so as to be rotatable around its own axis Y1, and has an upper jaw portion 51 located on the upper side in the direction of the axis Y1 and an axis Y1 on the outer peripheral surface. A lower jaw portion 52 located on the lower side in the direction and a molding recess 53 for molding the outer peripheral surface of the winding portion 15 between the upper jaw portion 51 and the lower jaw portion 52 are formed along the circumferential direction. Here, the axis Y1 of the first winding roll 50 is gradually increased upward in the axis X direction with respect to the axis X of the can lid 10 and the can body 20 sandwiched between the chuck member 41 and the lifter 45. As shown by an arrow E in FIG. 5, the chuck member 41 is spaced apart and approached in the radial direction as shown by an arrow E in FIG. 5 so as to be separated from the axis X. . Therefore, the first winding roll 50 comes into sliding contact with the curled portion 14 of the can lid 10 with the axis Y1 inclined with respect to the axis X of the can lid 10 and the can body 20. ing.

  FIGS. 1 and 4 are cross-sectional views of the main part of the cross section along the axis Y1 of the first winding roll 50 and the axis X of the can lid 10 and the can body 20. In the first winding tightening roll 50 of the present embodiment, as shown in FIGS. 1 and 4, the upper jaw portion 51 is provided to recede inward in the radial direction of the first winding tightening roll 50. Further, as shown in FIG. 4, the molding concave portion 53 has a shape in which three arcuate surfaces 54 to 56 and a straight portion 57 are continuously connected in order from the upper jaw portion 51 to the lower jaw portion 52, and has an axis Y1. , The first arc surface (arc surface with radius R1) adjacent to the upper jaw 51 is the first arc surface 54, the next arc surface (arc surface with radius R2) is the second arc surface 55, and the molding recess. A circular arc surface (an arc surface having a radius R3) located at the lowermost position in 53 is a third arc surface 56, and a straight line portion connecting the third arc surface 56 and the lower jaw portion 52 is a linear portion 57. As shown in FIG. 4, the straight portion 57 has a third arc surface 56 located at the lowest position in the molding recess 53 and an arc of the lower jaw portion 52 in the cross section along the axis Y1 of the first winding roll 50. The tangent line connects the surface 52a.

Further, the straight line portion 57 is provided at an angle β with respect to the orthogonal line H orthogonal to the axis Y1, and the angle β is provided at -3 ° or more and 5 ° or less. Note that the angle β increases upward (in the upper jaw 51 side) in the direction of the axis Y1 as it goes outward in the radial direction of the first winding roll, that is, away from the deepest position (bottom surface) of the molding recess 53. The case of inclining toward is negative (-: minus). On the other hand, the case where it is inclined downward (in the lower jaw 52 side) in the direction of the axis Y1 is positive (+: plus).
In the example shown in FIG. 4, the angle β of the straight portion 57 is positive, and the upper edge portion (upper jaw portion 51 side) and the lower edge portion (lower jaw portion 52 side) of the molding recess 53 are The first winding roll 50 is configured so as to be separated from each other toward the outer side in the radial direction.

Further, the surface of the molding recess 53 configured in this manner is subjected to a surface treatment such as shot peening so that the rotational force of the can lid 10 and the can body 20 can be reliably transmitted to the first winding roll 50. The surface roughness is set to a maximum height of Rmax 1.0 or more, preferably Rmax 1.0 or more and 3.0 or less. Thus, by performing the surface treatment by shot peening treatment or the like, the frictional force of the surface of the molding recess 53 at the time of contact with the can lid 10 increases, and the first winding roll is faster than the case where the surface treatment is not performed. The rotation speed of 50 can be synchronized with the rotation speed of the can lid 10.
4 is the center of curvature of the first arcuate surface 54, symbol C2 is the center of curvature of the second arcuate surface 55, and symbol C3 is the center of curvature of the third arcuate surface 56.

  Further, the groove width GL of the forming recess 53 is an imaginary line I (shown by a broken line in FIG. 4) extending from the maximum outer peripheral position of the lower jaw 52 to the perpendicular Z drawn in parallel with the axis Y1. ) To obtain an axial distance (a distance in a direction parallel to the axial center Y1) from P3, which is the intersection of the imaginary line I and the perpendicular Z, to P1, which is the intersection of the perpendicular Z and the molding recess 53. . Further, the groove depth GD is a radial distance from the perpendicular Z to the deepest position of the molding recess 53 (a distance in a direction orthogonal to the perpendicular Z).

Specifically, as described above, the curl height CL of the curled portion 14 is set to 2.0 mm or more and 2.4 mm or less, and the curl width CD is set to 0.7 mm or more and 1.0 mm or less (particularly 0.7 mm or more and 0.85 mm). For example, the first winding roll 50 for winding the can lid 10 having a nominal diameter of 204 is provided such that the groove width GL of the molding recess 53 is 1.9 mm to 2.2 mm, and the groove depth The length GD is set to 1.0 mm or more and 1.3 mm or less.
In addition, the radial distance from the outer peripheral edge of the linear portion 57 of the molding recess 53 (the connection point P2 between the molding recess 53 and the lower jaw 52) to the deepest position of the molding recess 53 is A, and the radial direction of the linear portion 57 When the length is L, the ratio of the length L to the distance A (L / A) is set to 0.09 or more and 0.33 or less.

The second winding roll 60 presses the curl part 14 of the can lid 10 and the flange part 23 of the can body 20 processed so as to be wound inward in the radial direction by the first winding roll 50 inward in the radial direction. Then, crushing is performed to form the outer peripheral surface of the final double winding portion 16 shown in FIG.
As shown in FIG. 5, the second winding roll 60 has a substantially disc shape, and a molding recess for forming the double winding part 16 between the upper jaw part 61 and the lower jaw part 62 on the outer peripheral surface. 63 is provided in a groove shape along the circumferential direction, and is configured to be rotatable around its own axis Y2 parallel to the axis X of the can lid 10 and the can body 20.

  Then, a can winding method using the can winding device 100 configured as described above will be described. In addition, although the can lid 10 and the can body 20 are partially deformed by the tightening process, in the following description, the can lid 10 and the can body 20 are before, during and after the tightening. The same reference numerals are given.

  First, as shown in FIG. 5, the flange portion 23 of the can body 20 placed on the lifter 45 is covered with the curled portion 14 of the can lid 10 as shown in FIG. 1A, and the chuck member 41 is attached to the can lid from above. 10, the can lid 10 and the can body 20 are sandwiched between the chuck member 41 and the lifter 45 in the direction of the axis X and rotated about the axis X. Then, from the outside in the radial direction, the first winding roll 50 is brought into sliding contact with the curl portion 14 of the can lid 10 and the flange portion 23 of the can body 20 to process the winding portion 15 (winding) Process).

  Specifically, the first winding roll 50 is formed by turning the first winding roll 50 from the outside in the radial direction of the can lid 10 and the can body 20 as shown in FIG. The curled portion 14 of the can lid 10 and the flange portion 23 of the can body 20 are inserted into the recess 53. At the start of contact between the curled portion 14 and the molding recess 53 in this entrainment step, the contact start position S between the curl portion 14 and the molding recess 53 is radially inward from the perpendicular Z as shown in FIG. Then, the curved surface of the outer peripheral surface in the middle of the curled portion 14 first comes into sliding contact with the molding recess 53. For this reason, the curved surface of the curled portion 14 is smoothly pushed down from the contact start position S and guided along the molding recess 53. Therefore, when the first winding roll 50 shown in FIG. 1B rotates once, the curled portion 14 can be wound inwardly. Further, the curled portion 14 of the can lid 10 and the flange portion 23 of the can body 20 are integrally curled inward along the molding recess 53, and the curled portion 14 is entrapped while being folded from the outside of the flange portion 23 into a bowl shape. In this way, finally, as shown in FIG. 2, the entangled portion 15 is formed.

Next, after the first winding roll 50 is spaced radially outward from the winding portion 15 and the processing (winding step) by the first winding roll 50 is completed, as shown by the arrow in FIG. The winding roll 60 is made to approach the winding part 15 from the radially outer side, and the winding part 15 is further pressed toward the inner side in the radial direction so that the double winding part 16 is pressed as shown in FIG. Is processed (crushing step).
At this time, the annular projecting portion 42 of the chuck member 41 is fitted to the counter sink portion 12 of the can lid 10, and the wall surface 43 of the outer peripheral surface of the chuck member 41 can connect the chuck wall portion 13 of the can lid 10 to the can. The can lid 10 and the can body 20 are sandwiched between the wall surface 43 and the second winding roll 60 by supporting from the radially inner side of the lid 10. As a result, a double tightening portion 16 in which a compound (not shown) is interposed between the can lid 10 and the can body 20 in a compressed state is formed, and the can lid 10 is attached to the flange portion 23 of the can body 20. The

In the can winding apparatus 100, the first winding roll 50, and the can winding method of the present embodiment configured as described above, the curl width CD (the length in the radial direction from the maximum outer peripheral position of the curled portion 14 to the tip end). The depth (groove depth GD) of the forming recess 53 of the first winding roll 50 in the can lid 10 having a thickness of 0.7 mm or more and 1.0 mm or less (particularly 0.7 mm or more and 0.85 mm or less). Even if it is shallow, the contact start position S of the curled portion 14 with the molding concave portion 53 is arranged not on the tip of the curled portion 14 but on the middle outer peripheral surface of the curled portion 14. Thereby, compared with the case where the shaping | molding recessed part 53 contacts with the front-end | tip of the curled part 14, the curled part 14 can obtain a frictional resistance reliably, and the curled part 14 has an arcuate surface (here) Then, it can wind up smoothly along the 1st circular arc surface 54 or the 2nd circular arc surface 55). Then, as the curling of the curled portion 14 proceeds, the curled portion 14 is wound up along the arc surface (herein, the third arc surface 56) and the linear portion 57 positioned below the forming recess 53. When attention is paid to the lower surface in the molding recess 53, the ratio (L / A) between the radial distance A of the molding recess 53 and the radial length L of the linear portion 57 is 0.09 or more and 0.0. 33 or less, and by adjusting the arrangement and size of the linear portion 57 with respect to the arc surface (third arc surface 56) of the molding recess 53 in this way, the curl portion 14 is excessively entrained or entrained. The shortage can be prevented, and the problem of lowering the winding property and the occurrence of reverse wrinkle due to the curled width CD of the curled portion 14 being reduced can be solved. Furthermore, since contact between the tip of the curled portion 14 and the molding concave portion 53 is avoided at the start of contact between the curled portion 14 and the molding concave portion 53, generation of thin chips can be reliably prevented.
If the ratio (L / A) is less than 0.09, the roll-up property is lowered, and it becomes difficult to obtain sufficient sealing performance of the can. Moreover, when the ratio (L / A) exceeds 0.33, generation of thin chips cannot be prevented.

  In the present embodiment, in the entrainment step, the contact start position S between the curled portion 14 and the molding concave portion 53 is arranged on the radially inner side from the maximum outer peripheral position (perpendicular line Z) of the lower jaw part 52. Compared to the case where the outer peripheral surface of the curled portion 14 is arranged on the outer side in the radial direction from Z, it is easy to smoothly guide the outer peripheral surface of the curled portion 14 along the shape of each arc surface of the molding recess 53. Therefore, the entraining part 15 can be processed into a stable shape, and good sealing performance of the can can be ensured.

Furthermore, the linear part 57 of the shaping | molding recessed part 53 is provided with the angle (beta) of -3 degrees or more and 5 degrees or less with respect to the orthogonal line H as mentioned above. In this way, by setting the angle β to -3 ° or more and 5 ° or less and providing the straight portion 57, the outer peripheral surface of the curled portion 14 can be smoothly guided along the straight portion 57 and the winding property is improved. be able to.
When the angle β is smaller than −3 °, when the first winding roll 50 is released from the winding portion 15 after the winding portion 15 is processed, the winding portion 15 and the lower jaw portion 52 are separated from each other. It becomes easy to get caught, and there is a possibility that the can lid 10 may be scratched or paint residue may be generated by scraping the portion. On the other hand, when the angle β is larger than 5 °, the windability is deteriorated, and reverse wrinkle is likely to be generated.

Next, the results of a comparative experiment conducted to confirm the effect of the present invention will be described. In the following description, for convenience, the same reference numerals used in the above embodiment are used.
The can lid 10 has a nominal diameter of 204, is formed of an aluminum alloy plate, has a curl height CL of the curled portion 14 of 2.0 mm to 2.4 mm, and a curl width CD of 0.7 mm to 1. What was formed in 0 mm or less and board thickness 0.205mm or more and 0.225mm or less was used. The can body 20 was formed of an aluminum alloy plate and having a flange portion 23 having a width FW of 2.0 mm to 2.5 mm and a thickness of 0.16 mm to 0.20 mm. .

  And the can body 20 was filled with the internal solution (water) of gas volume 2.7, the can lid 10 was wound up, and the drink can was produced. At that time, as shown in Table 1, the sample (1) in which the ratio (L / A) to the groove width GL, the groove depth GD, and the length L with respect to the radial distance A was changed by changing each dimension. The first canning roll 50 of (7) was formed, and 20 cans of beverage cans were produced each of which was fastened by the first winding rolls 50 having different shapes. Further, the can lid 10 is wound and tightened so that the contact start position S between the curled portion 14 of the can lid 10 and the forming recess 53 of the first winding roll 50 becomes the middle outer peripheral surface of the curled portion 14. It was. Note that the first winding roll 50 and the can lid 10 were configured such that the axis Y1 of the first winding roll 50 was tilted with respect to the axis X of the can lid 10 and initially contacted. The winding speed was a speed corresponding to 2000 cans / minute.

In Table 1, the evaluation result about each drink can which was wound up with each 1st winding roll 50 is shown.
Each beverage can was observed and (a) thin chips and (b) the presence or absence of reverse wrinkles were evaluated, and (c) the cover hook dimensions were measured. In addition, a drop test was performed on each beverage can, and (d) a drop leak was evaluated.
In addition, about the sample (1), the 1st winding roll 50 which eliminated the linear part 57 of the shaping | molding recessed part 53, and connected the 3rd circular arc surface 56 and the circular arc surface 52a of the lower jaw part 52 directly was comprised. For this reason, in the sample (1), the dimension relating to the straight portion 57 in Table 1 is described as “-”.

  The thin chip is a thread-like aluminum piece generated at the time of winding, and the evaluation of this thin chip is made so that the first winding roll 50 is fixed so as not to rotate around its axis Y1. A severe test was performed by winding the can lid 10 in a state where thin chips are likely to be generated. In this case, the first winding roll 50 does not rotate not only at the start of winding tightening but also after the start of winding tightening. It is always a condition that tends to generate thin chips. And in this severe test, while the number of cans in which thin chips were generated is described in Table 1, the condition in which even one of 20 cans had thin chips generated was rejected as “x”, and no thin chips were generated. (Can number 0) was set to pass “◯”.

  In addition, the reverse wrinkle is one that breaks through the can body 20 to create a hole, or a protrusion wrinkle that has a high possibility. For the evaluation of the reverse wrinkle, the movement amount (pushing amount) in the radial direction of the first winding roll 50 is set to be large so that the radial thickness of the winding portion 15 becomes smaller than usual. A severe test was carried out by tightening the can lid 10 in a state where it easily occurs. In this severe test, the number of cans where reverse wrinkles occurred is listed in Table 1. The condition where reverse wrinkles occurred even in 1 can of 20 cans was judged as “failed”, and conditions where no reverse wrinkles occurred (cans) The number 0) was regarded as a pass “◯”.

  The cover hook is a bent length (length CH shown in FIG. 3) of the curled end of the can lid 10 in the double winding portion 16. Regarding the evaluation of the cover hook, the axial force that is sandwiched between the lifter 45 and the chuck member 41 in the can axis direction is set higher than usual, and the can lid 10 is tightened in a state where the dimensions of the cover hook tend to be long. The severe test was carried out. It was evaluated whether the size of the cover hook was in the range of 1.50 mm to 2.00 mm. The evaluation of the cover hook is described in Table 2 as the number of beverage cans whose cover hook dimension is less than 1.50 mm or exceeding 2.00 mm and out of the above range. The condition in which the outside of the range was out of the range was judged as “failed” “x”, and the condition in which the cover hook dimensions of all 20 cans were in the range was judged as “passed”.

  And, as described above, the evaluation of the fall leak is that the beverage can, which is wound with the internal pressure applied with the gas volume 2.7, is turned upside down from a height of 80 cm in an inverted posture with the can lid 10 facing down. A rigorous test was carried out by dropping it on the top and checking the presence or absence of leakage of the contents. The number of cans with leakage of contents is listed in Table 1, and the condition where leakage occurred even with 1 of 20 cans was rejected as “x”, and the condition where leakage did not occur (number of cans 0) was accepted. “○”.

  As described above, the evaluations of (a) thin chips, (b) reverse wrinkles, (c) cover hook dimensions, and (d) fall leakage are based on conditions more severe than standards that can be used without problems as products. The test was conducted.

As is apparent from the results in Table 1, the samples (2) to (7), that is, the groove width GL is provided in the range of 1.9 mm to 2.2 mm, and the groove depth GD is set to 1.0 mm to 1.3 mm. Winding is tightened by a first winding roll 50 that is provided and has a ratio (L / A) of the radial length L of the linear portion 57 to the radial distance A of the molding recess 53 of 0.09 to 0.33. No thin chips were generated for the beverage cans that had been subjected to. In addition, it was confirmed that the cover hook dimensions could be formed within the specified range without generating reverse wrinkles, leakage in the drop test did not occur, and good sealing performance of the can could be secured.
In addition, in the sample (1) that was wound with the first winding roll 50 that does not have the straight portion 57, there was a sample in which the curling property of the curled portion 14 was deteriorated and the sealing performance of the can could not be ensured. . Further, in the sample (7) in which the ratio (L / A), which is the ratio of the radial length L of the linear portion 57 to the radial distance A of the molding recess 53, is set to exceed 0.33, thin chips are generated. There was something to do.

  In addition, this invention is not limited to the thing of the structure of the said embodiment, In a detailed structure, it is possible to add a various change in the range which does not deviate from the meaning of this invention.

DESCRIPTION OF SYMBOLS 10 Can lid 11 Panel part 12 Counter sink part 13 Chuck wall part 14 Curl part 15 Winding part 16 Double winding part 20 Can body 21 Body part 21a Diameter reduction part 22 Neck part 23 Flange part 30 Tightening unit 41 Chuck member 42 Annular Projection 43 Wall surface 45 Lifter 46 Lifter plate 47 Holder 50 First winding fastening 51 Upper jaw 52 Lower jaw 53 Molding recess 54 First arc surface 55 Second arc surface 56 Third arc surface 57 Linear portion 60 Second volume Fastening roll 61 Upper jaw 62 Lower jaw 63 Molding recess 100 Can winding device

Claims (6)

A can lid provided with a curled portion rewound inward in the radial direction is a method of tightly winding and tightening a can by closely contacting a flange portion provided in an opening of a can body,
The can lid and the can body are sandwiched in the axial direction of the can body and rotated around the axial center, and from the outside in the radial direction, a first winding roll is brought into sliding contact with the flange portion and the An entrainment process of entraining the curled portion and processing the entrainment portion;
A crushing step of pressing the flange portion and the curl portion processed by the winding step toward the radially inward using a second winding roll to process a double winding portion,
The first winding roll has, on its outer peripheral surface, an upper jaw portion positioned on the upper side in the axial direction of the first winding roll, a lower jaw portion positioned on the lower side in the axial direction, the upper jaw portion, and the lower jaw. And a molding concave portion for molding the outer peripheral surface of the entrainment portion with the portion is formed along the circumferential direction,
The molding recess has a shape in which a plurality of arcuate surfaces and linear portions are continuously connected in order from the upper jaw portion to the lower jaw portion,
The straight line portion is a tangent line connecting a circular arc surface located in the lowest part in the molding recess and a circular arc surface of the lower jaw part in a cross section along the axis of the first winding roll,
At the start of contact between the curled portion and the molding recess in the entrainment step,
A contact start position between the curled portion and the molding recess is provided on the outer peripheral surface in the middle of the curled portion,
The edge of the outer peripheral surface tip of the curl part is provided on the radially outer side of the first winding roll with respect to the outer peripheral side edge of the linear part, and the first winding more than the maximum outer peripheral position of the lower jaw part. A method of winding a can provided on the inner side in the radial direction of the fastening roll. In the entrainment step,
The can winding method according to claim 1, wherein the contact start position is disposed radially inward of the first winding roll with respect to a maximum outer peripheral position of the lower jaw. A can lid provided with a curled portion wound inward in the radial direction is used when a can is formed by tightly attaching to a flange portion provided at the opening of the can body and tightening,
The can lid has a curl height of 2.0 mm or more and 2.4 mm or less, which is a distance in a direction parallel to the axis of the can lid, and a radial direction from the maximum outer peripheral position of the curl portion to the tip. The curl width CD as a length is formed to be 0.7 mm or more and 1.0 mm or less,
A first winding roll that slidably comes into contact with the can lid and the can body from the outside in the radial direction and winds the flange portion and the curl portion to process the winding portion,
On the outer peripheral surface, an upper jaw portion located on the upper side in the axial direction of the first winding roll, a lower jaw portion located on the lower side in the axial direction, and the winding portion between the upper jaw portion and the lower jaw portion. A molding recess for molding the outer peripheral surface is formed along the circumferential direction,
The molding recess has a shape in which a plurality of arcuate surfaces and linear portions are continuously connected in order from the upper jaw portion to the lower jaw portion,
The straight line portion is a tangent line connecting a circular arc surface located in the lowest part in the molding recess and a circular arc surface of the lower jaw part in a cross section along the axis of the first winding roll,
From the intersection P3 of the perpendicular Z drawn parallel to the axis of the first winding roll from the maximum outer peripheral position of the lower jaw and the imaginary line I extending the straight portion radially outward, the perpendicular Z and the The groove width GL of the axial distance to the intersection P1 with the molding recess is provided in the range of 1.9 mm to 2.2 mm,
The groove depth GD of the radial distance from the perpendicular Z to the deepest position of the molding recess is 1.0 mm or more and 1.3 mm or less,
The radial length with respect to the radial distance A, where A is the radial distance from the outer peripheral side edge of the linear portion to the deepest position of the molding recess, and L is the radial length of the linear portion. A first winding roll provided with an L ratio (L / A) of 0.09 to 0.33.   The straight portion is provided at an angle β with respect to an orthogonal line orthogonal to the axis of the first winding roll in a cross section along the axis of the first winding roll, and the angle β is The 1st winding roll of Claim 3 provided in -3 degrees or more and 5 degrees or less. A can tightening device for forming a can by tightening a can lid provided with a curled portion wound inwardly in a radial direction in close contact with a flange portion provided in an opening of the can body,
The can lid has a curl height of 2.0 mm or more and 2.4 mm or less, which is a distance in a direction parallel to the axis of the can lid, and a radial direction from the maximum outer peripheral position of the curl portion to the tip. The curl width CD as a length is formed to be 0.7 mm or more and 1.0 mm or less,
A chuck member in contact with the can lid;
A lifter that holds the can body and moves up and down in the axial direction;
The flange portion and the curl portion are wound around the can lid and the can body, which are sandwiched in the axial direction by the chuck member and the lifter and rotate about the axial center, in sliding contact from the outside in the radial direction. A first winding roll for processing the entrainment part;
A second winding roll that presses the flange portion and the curl portion wound by the first winding roll further radially inward to process a double winding portion;
The first winding roll is provided rotatably around its axis,
On the outer peripheral surface, the upper jaw part located on the upper side in the axial direction of the first winding roll, the lower jaw part located on the lower side in the axial direction, and the entrainment part between the upper jaw part and the lower jaw part And a molding concave portion for molding the outer peripheral surface of is formed along the circumferential direction,
The molding recess has a shape in which a plurality of arcuate surfaces and linear portions are continuously connected in order from the upper jaw portion to the lower jaw portion,
The straight line portion is a tangent line connecting a circular arc surface located in the lowest part in the molding recess and a circular arc surface of the lower jaw part in a cross section along the axis of the first winding roll,
From the intersection P3 of the perpendicular Z drawn parallel to the axis of the first winding roll from the maximum outer peripheral position of the lower jaw and the imaginary line I extending the straight portion radially outward, the perpendicular Z and the The groove width GL of the axial distance to the intersection P1 with the molding recess is provided in the range of 1.9 mm to 2.2 mm,
The groove depth GD of the radial distance from the perpendicular Z to the deepest position of the molding recess is 1.0 mm or more and 1.3 mm or less,
The radial length with respect to the radial distance A, where A is the radial distance from the outer peripheral side edge of the linear portion to the deepest position of the molding recess, and L is the radial length of the linear portion. A can winding device provided with a ratio of L (L / A) of 0.09 to 0.33.   The linear portion of the first winding roll forms an angle β with respect to an orthogonal line H perpendicular to the axis of the first winding roll in a cross section along the axis of the first winding roll. The winding fastening apparatus according to claim 5, wherein the angle β is provided in a range of −3 ° to 5 °.

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