JPH0223313B2 - - Google Patents

Description

Detailed Description of the Invention <Technical Field> The present invention provides a plurality of slits extending in the circumferential direction at intervals in the lower part of a synthetic resin skirt wall of a container lid, and a plurality of slits remaining between the slits. The present invention relates to a method and apparatus for forming a weakened line consisting of several bridges.

<Prior Art> As is well known to those skilled in the art, container lids for containers such as food and beverage bottles having so-called pilfer-proof properties (tamper-proof properties) include a top wall and a tube hanging from the top wall. A weakened line is provided at the lower part of the skirt wall, and the weakened line includes a plurality of slits extending in the circumferential direction at intervals in the circumferential direction and a plurality of bridge portions remaining between the slits. The types provided are widely used in practice.

The lines of weakness in such types of container closures generally create radially extending cuts in the skirt wall at circumferentially spaced intervals, thus forming the slits. Therefore, in recent years, at least the lower part of the skirt wall, usually the entire top wall and skirt wall, is made of a suitable synthetic resin such as polypropylene or polyethylene, instead of a thin metal plate such as aluminum-based alloy or chromium-treated steel. Container lids formed from synthetic resin have been proposed and put into practical use, but at least when the lower part of the skirt wall is made of synthetic resin, there are the following problems that need to be solved regarding the formation of the weakened line. .

In other words, the plurality of bridges remaining between the plurality of slits in the weakened line can be maintained without being broken when the container lid is attached to the mouth and neck of the container to seal the container. It is important that at least a large portion of the bridging portion be sufficiently easily broken when the container lid is removed from the mouth and neck of the container to open the container. From this point of view, it is important that the residual cross-sectional area of the bridging portion be set within the required range with sufficient precision.
On the other hand, if the skirt wall is made of a thin metal plate, the slits can be formed by making the spacing between the slits as small as required, and thus the cross-sectional area of the bridge can be made within the required range. However, when the skirt wall is made of synthetic resin, it has relatively high elasticity and therefore has poor cutting characteristics compared to thin metal sheets.If the distance between the slits is made as small as required, There is a tendency for the bridge portion to break when cutting the slit. In order to avoid this tendency, it is necessary to make the spacing between the slits larger than the required value, and in order to bring the residual cross-sectional area of the bridge within the required range, the radius at the bridge must be increased. It becomes necessary to make cuts partially in the direction.

Therefore, Japanese Patent Application Laid-Open No. 56-161953 has cutting blades for through-cutting located at intervals in the circumferential direction and cutting blades for partial cutting located between the cutting blades for through-cutting, and A cutting tool (see Fig. 4 in addition to the above-mentioned Japanese Unexamined Patent Publication No. 56-161953) is used in which the leading edge of the cutting blade for through-cutting is recessed by a predetermined amount from the leading edge of the cutting blade for through-cutting. hand,
It has been proposed to form the weakened line in a synthetic resin skirt wall. When the cutting tool of the above configuration is applied to create a cut in the synthetic resin skirt wall, a slit is formed by the radial through cut created by the through cut cutting blade, and a slit is formed by the partial cut cut. A radial partial incision is made in the bridge between the slits by means of the cutting blade, thus bringing the residual cross-sectional area of the bridge to the required range.

However, the method of forming a weakened line as disclosed in Japanese Patent Application Laid-open No. 161953/1983 is still not fully satisfactory, and (a) manufacturing of the cutting tool is relatively difficult and expensive; B) It is often desirable to change or adjust the partial cut depth at the bridge portion depending on the synthetic resin material, etc.
The partial cutting depth in the bridge section is uniquely defined by the amount of retraction of the leading edge of the partial cutting blade relative to the leading edge of the through cutting blade, so unless a new cutting tool is manufactured. It is impossible to change or adjust the partial depth of cut in the bridge; (c) the residual shape or dimensions (and thus the residual cross-sectional area) of the bridge are inconsistent and unstable (the reason for this is not always clear); However, the present inventors believe that this is caused by the simultaneous operation of different types of cutting blades, namely, a cutting blade for a through cut and a cutting blade for a partial cut.

<Object of the invention> The present invention has been made in view of the above facts, and solves the problems (a), (b), and (c) above, and has a structure in which a circumferential direction is provided at the bottom of the synthetic resin skirt wall. Through-cuts are formed at intervals to form the slits, and partial cuts of the required depth are made at the bridges between the slits to bring the residual area of the bridges to the required value, thus making the required area. It is an object of the present invention to provide a new and excellent method and apparatus capable of forming a weakened line.

<Summary of the Invention> As a result of intensive research and experiments, the present inventors have surprisingly discovered a through-cutting method that creates through-cuts at intervals in the circumferential direction in the lower part of a synthetic resin skirt wall to form a slit. and a partial cutting step of creating a radial partial cut between the slits to bring the residual cross-sectional area of the bridge portion to a desired value,
If the above is performed separately and independently using an outer cutting tool for through-cutting (first stationary outer cutting tool) and an outer cutting tool for partial cutting (second stationary outer cutting tool), which are respectively manufactured separately, It has been found that the above objectives can be achieved by solving (a), (b) and (c).

That is, according to the present invention, a container lid has a top wall and a cylindrical skirt wall hanging from the top wall, and at least the lower part of the skirt wall is made of synthetic resin. forming a weakened line consisting of a plurality of slits extending circumferentially at intervals in the direction and a plurality of bridges remaining between the slits; using an outer cutting tool for through-cutting; a through-cutting step that creates a plurality of circumferentially spaced circumferentially spaced cuts in a lower portion of the skirt wall that extend radially through and circumferentially; and an outer cutter for through-cutting that is fabricated separately; Separately from the through-cutting step, using a partial cutting outer cutting tool, cut radially into the lower part of the skirt wall, at least in a major portion of the area to be attached to the plurality of bridges. A method is provided, comprising: a partial cutting step of partially creating a cut;

Further, according to the present invention, in a container lid having a top wall and a cylindrical skirt wall hanging from the top wall, and at least a lower portion of the skirt wall is made of synthetic resin, a peripheral portion is provided at a lower portion of the skirt wall. A device for forming a weakened line consisting of a plurality of slits extending in the circumferential direction at intervals in the direction and a plurality of bridge portions remaining between the slits; a plurality of container lid transport means mounted on the support at spaced intervals in the direction, the container lid transport means including an inner cutting tool rotatably mounted about its own central axis; , a rotational drive source for rotating the support to move the container lid conveying means through a circular travel path that sequentially passes through a feeding zone, a cutting zone, and a discharge zone; rotation means for rotating the inner cutting tool about its own central axis as it is moved along the inner cutting tool; and container lid supply means for supplying container lids to the container lid conveying means in the feeding zone. a first stationary outer cutting tool extending in an arc along the circular path of travel of the inner cutting tool at an upstream portion of the cutting zone; a second stationary outer cutting tool, fabricated separately from the first stationary outer cutting tool, extending in an arc along the container lid for ejecting the container lid from the container lid conveying means in the ejection zone; ejecting means, wherein the container lid fed to the container lid conveying means in the supply zone is fitted over the inner cutting tool, and in the cutting zone, the first stationary outer cutting tool and the first stationary outer cutting tool the skirt wall at circumferentially spaced intervals by one of the first stationary outer cutting tool and the second stationary outer cutting tool. A plurality of radially penetrating and circumferentially extending cuts are created in the lower portion, and the first
The other of the stationary outer cutting tool and the second stationary outer cutting tool partially cuts a portion of the lower portion of the skirt wall, viewed in the radial direction, at least at a majority of the portions to be connected to the plurality of bridges. An apparatus is provided, characterized in that a cut is generated in the cut.

<Preferred Specific Examples of the Invention> Hereinafter, a more detailed description will be given with reference to the accompanying drawings. FIG. 1 illustrates a container lid before a line of weakness is formed in accordance with the present invention. The container lid 2 shown in FIG. 1 is entirely molded from a suitable synthetic resin material such as polypropylene or polyethylene by a suitable molding method such as compression molding or injection molding. The container lid 2 includes a circular top wall 4 and a cylindrical skirt wall 6 that hangs down from the periphery of the top wall 4. skirt wall 6
includes an upper part 8 and a lower part 10, the upper part 8 being relatively thick, and the lower part 10 having an intermediate thickness part 12 following the upper part 8 and a relatively thin part 14. An annular protrusion 16 is formed on the inner peripheral surface of the upper end portion of the upper portion 8 of the skirt wall 6 and protrudes radially inward therefrom. Further, a female thread 18 is also formed on the inner peripheral surface of the upper part 8 of the skirt wall 6. skirt wall 6
The outer circumferential surface of the upper part 8 is formed with unevenness or knurling 20 to prevent the fingers from slipping when rotating the container lid 2 by placing the fingers thereon.
On the other hand, a plurality of locking flap pieces 22 are formed at intervals in the circumferential direction on the inner peripheral surface of the lower part 10 of the skirt wall 6, more specifically, the relatively thin portion 14 thereof (such locking flap pieces 22 are formed at intervals in the circumferential direction). When the container lid 2 is attached to the mouth and neck of the container as required, the flap piece 22
(It is locked to an annular locking flange formed on the outer peripheral surface of the mouth and neck).

Referring to FIG. 2 in conjunction with FIG. 1, the present invention provides for forming a weakened line in the lower part 10 of the skirt wall 6 in said container lid 2, indicated generally by the numeral 24, and also in the skirt wall 6 in said container lid 2. It concerns forming a vertical cut 25 in the lower part 10 of the wall 6. In the illustrated embodiment, a line of weakness 2 is provided in the mid-thickness portion 12 of the lower portion 10 of the skirt wall 6 of the container lid 2, as clearly shown in FIG.
4 is formed. The weakened line 24 is composed of a plurality of slits 26 extending in the circumferential direction at intervals in the circumferential direction and bridging portions 28 remaining between the slits 26. Bridge section 2
One of the 8 bridge parts 28A has a circumferential dimension and/or a radial dimension larger than the other bridge parts 28 (this point will be further referred to later), and has a larger circumferential dimension and/or radial dimension than the other bridge parts 28. It is also made into a high-strength bridge with increased strength. and,
The vertical cut 25 extends downward from a position aligned with or close to at least one side of the high-strength bridge portion 28A, and both sides in the illustrated case. Such vertical cut 2
5 may extend to the lower end of the skirt wall 6, but in the illustrated example it extends only to the lower end of the intermediate thickness section 12 of the lower part 10 of the skirt wall 6.

In the illustrated embodiment, a line of weakness 24 and a vertical cut 25 are formed in the container lid 2 as will be described in detail later.
After (or before) forming a sealing liner 29 on the inner surface of the top wall 4, as shown in FIG.
will be applied. Such a sealing liner 29 is produced by supplying a molten liner material, which may be an appropriate synthetic resin, to the inner surface of the top wall 4 of the container lid 2 held in an inverted state, and then applying an embossing tool into the container lid 2 into the desired shape. is inserted, thus connecting the inner surface of the top wall 4 and the annular protrusion 1.
It can be conveniently applied by stamping in the area defined by 6 and 6.

The container lid 2 shown in FIG. 2 is fitted onto the neck (not shown) of the container, and then the container lid 2 is rotated clockwise as viewed from above in FIG. It is attached to the mouth and neck by sufficiently screwing the female thread 18 onto the male thread formed on the outer peripheral surface of the mouth and neck. In this way, the locking flap piece 22 of the container lid 2 passes through the annular locking flange formed on the outer circumferential surface of the mouth and neck and is locked on the lower surface thereof, and the sealing liner 29 is brought into close contact with the top surface of the mouth and neck. I am forced to seal my mouth and neck. When the container lid 2 is rotated counterclockwise when viewed from above in FIG. 2 to open the container, the bridges 28 other than the high-strength bridges 28A in the weakened line 24 are broken, and the two Following one of the longitudinal cuts 25, a longitudinal break is produced up to the lower end of the skirt wall 6, thus releasing the locking flap piece 22 from the annular locking flange, after which the container lid 2 is removed from the neck. be done.

Thus, the container lid 2 as shown in FIG.
This is merely an example of a container lid to which the method and device according to the invention may be applied, and does not directly relate to the novel features of the method and device according to the invention, and therefore does not refer to the container lid 2 itself. Detailed explanation will be omitted.

FIG. 3 shows the weakening line 24 on the container lid 2.
1 schematically illustrates an embodiment of an apparatus constructed in accordance with the present invention for forming vertical cuts 25 and 25; The apparatus illustrated in FIG.
It has a main part shown in . To explain with reference to FIG. 4, the main part 30 has a stationary base 32 fixed at a predetermined position, and this stationary base 32 has a plurality of fastening bolts 34 (one of which is shown in FIG. 4). (only one of which is shown) fixes the lower end of a stationary support shaft 36 that extends substantially vertically. and,
A rotating support 38 having a generally cylindrical shape as a whole is arranged around the stationary support shaft 36 . A bearing member 39 is provided between the rotating support 38 and the stationary base 32.
A bearing member 41 is interposed between the rotating support 38 and the stationary support shaft 36, so that the rotation support 38 is rotatably mounted around the stationary support shaft 36. . An annular input gear 40 is fixed to the lower end of the rotation support 38 . A rotary drive source 42 such as an electric motor is drivingly connected to the input gear 40 via a suitable driving connection means (not shown). Thus, the rotary support 38 is rotated by the drive source 42 at a predetermined speed in the direction indicated by the arrow 44 in FIG. 3 (counterclockwise when viewed from above in FIG. 4).

An upper annular support plate 46 and a lower annular support plate 4 are provided on the upper part of the rotation support 38 at intervals in the vertical direction.
8 is fixed. These annular support plates 46 and 48 are provided with through openings 5 at a plurality of (nine in the illustrated case) positions at predetermined intervals in the circumferential direction.
0 and 52 are formed. In each of the plurality of positions, a shaft 54 extending through both the annular support plates 46 and 48 is supported by bearing sleeves 56 and 58 disposed within the through openings 50 and 52. , are mounted so as to be vertically movable up and down and rotatable about their respective central axes. The plurality of shaft bodies 54 are connected to the rotation support body 3.
The shaft body 54 rotates (revolutions) in conjunction with the rotation of the rotary support 38 .
Rotating means 60 for rotating the shafts 4 about their respective central axes and elevating means 62 for moving the shafts 54 up and down are provided. In the illustrated example, the rotation means 60 is comprised of a planetary gear mechanism. To explain in more detail, the shaft body 54
A planetary gear 64 is fixed to the upper part of each. On the other hand, a stationary support top plate 66 is fixed to the upper end of the stationary support shaft 36, and a plurality of suspension rods 68 (only two of which are shown in FIG. 4) are suspended from the support top plate 66. A sun gear 70, consisting of a stationary ring gear, is fixed via the rotor (shown). Each of the planetary gears 64 is locked to the sun gear 70, and thus each of the shafts 54 rotates counterclockwise (as seen from above in FIG. 4) in conjunction with the rotation of the rotary support 46. When the shafts 54 are caused to revolve (revolution), each of the shaft bodies 54 is caused to rotate clockwise when viewed from above in FIG. The elevating means 62 is composed of a cam mechanism. More specifically, a cylindrical cam block 72 is fixed to the upper end of the stationary support shaft 36 (immediately below the support top plate 66), and the outer peripheral surface of this cam block 72 has a
An annular cam groove 74 is formed. On the other hand, the shaft body 5
A bracket 75 is fixed to the upper end of each of the
A roller 76 is mounted on the bracket 75 so as to be rotatable about a central axis extending substantially horizontally. Each of the rollers 76 is connected to the cam groove 74.
It functions as a cam driven joint.
Thus, when the shaft bodies 54 are rotated in accordance with the rotation of the rotary support 46, each of the shaft bodies 54 is moved up and down according to the locus of the cam groove 74 (such up and down movements will be further referred to later). do).

A substantially cylindrical inner cutting tool 78 is fixed to the lower end of each of the shafts 54 . An annular cutting groove 80 is formed in the outer peripheral surface of the inner cutting tool 78 (the annular cutting groove receives a cutting blade of a first stationary outer cutting tool to be described later).

An annular flange portion 82 is formed at the lower portion of the rotation support body 38 . A plurality of through openings 84 are formed in this annular flange portion at a plurality of positions aligned with each of the shaft bodies 54 in the vertical direction. Referring to FIG. 5, a lower bearing member 86 and an upper bearing member 88 are disposed within each of the through openings 84. As shown in FIG. Lower bearing member 86
is fixed at a predetermined position within the through opening 84 by screwing into the through opening 84 . On the other hand, the upper bearing member 88 is mounted within the through opening 84 so as to be slidable in the vertical direction. A compression coil spring 90 is interposed between the lower bearing member 86 and the upper bearing member 88. The spring 90 resiliently biases the upper bearing member 88 upwardly. A receiving member 92 is attached to the lower bearing member 86 and the upper bearing member 88. The receiving member 92 has a disc-shaped receiving portion 94 and a cylindrical supported shaft portion 96 depending downwardly from the disc-shaped receiving portion 94. Axial branch 96
is rotatably and vertically movably mounted on the lower bearing member 86 and the upper bearing member 88. The shafted support 96 projects downward beyond the lower bearing member 86, and a nut 98 that is brought into contact with the lower surface of the lower bearing member 86 is screwed onto the protruding lower end of the shafted support 96. Receiving member 9
2 (therefore, the upper bearing member 88) is restricted from moving upward in the vertical direction. Receiving portion 94 of receiving member 92
A thrust bearing 100 is interposed between the lower surface of the upper bearing member 88 and the upper bearing member 88 . Therefore, it is understood that the receiving member 92 is mounted so as to be rotatable and to be able to escape downward together with the upper bearing member 88 against the elastic biasing action of the spring 90. It will be.

In the illustrated example, an annular member 102 located above the annular flange portion 82 is also fixed to the rotary support 38 . An annular flange portion 104 is formed at the upper end of the annular member 102, and the annular flange portion 104 has through openings 106 at each of a plurality of positions aligned with each of the receiving members 92 when viewed in the vertical direction. is formed. The inner diameter of the through opening 106 is larger than the outer diameter of the inner cutting tool 78 fixed to the lower end of the shaft 54, but somewhat smaller than the outer diameter of the container lid 2. As mentioned later, the annular flange portion 104 in which the through opening 106 is formed,
It functions as a so-called stripper for reliably separating the container lid 2 from the inner cutting tool 78. As understood from FIG. 3, approximately semicircular notches 108 are formed on the outer circumferential surface of the main portion of the annular member 102 at positions corresponding to each of the receiving members 92.
Therefore, each of the receiving members 92 is connected to the annular member 10.
It is exposed without being covered by the main part of No. 2.

The receiving member 92 cooperates with the inner cutting tool 78 fixed to the lower end of the shaft 54 to constitute container lid conveying means. Referring to FIG. 3, when the rotary support 38 is rotated in the direction shown by arrow 44, the receiving member 92 and inner cutting tool 78 are also rotated in the direction shown by arrow 44, and thus the receiving member 92 and the inner cutting tool 78 are also rotated in the direction shown by arrow 44. Member 92 and inner cutting tool 78
is a supply area 110, a cutting area 112 and a discharge area 11.
4 through a circular travel path sequentially passing through 4. In the supply area 110, the entire number is 1.
The above-mentioned receiving member 9 is
2 (this container lid 2 has the form as shown in FIG. 1, and the weakened line 24 and vertical cut 25 have not yet been formed).
is supplied. In the cutting zone 112, stationary outer cutting means, generally indicated by the number 118, act on the container lid 2 to cut the line of weakness 24 and the vertical cut 25 (second
form). Disposed in the discharge area 114 is a discharge means, generally designated by the number 120, for discharging the container lid 2 in which the weakened line 24 and the vertical cut 25 (FIG. 2) are formed from above the receiving member 92. .

Referring to FIG. 3, the container lid supply means 116 will be described. The container lid supply means 116, which may be of a known form per se, has a rotation shaft 122 which extends substantially vertically and is rotatably mounted. This rotating shaft 122 is provided with a turret plate 12 having a substantially disk shape.
4 is fixed, and the turret plate 124
A plurality of semicircular notches 125 (nine in the illustrated case) are provided at intervals in the circumferential direction on the outer peripheral edge of the
is formed. The radius of the notch 125 corresponds to the outer radius of the container lid 2. Below the turret plate 124, there is a portion 126a extending in an arc shape along the outer peripheral edge of the turret plate 124, and a portion 126a extending in a straight line from the upstream end (left end in FIG. 3) of the portion 126a to the left in FIG. Extending portion 12
A stationary support plate 126 having 6b is provided. The upper surface of the stationary support plate 126 is
The downstream end (the right end in FIG. 3) of the arcuate portion 126a of the stationary support plate 126 is substantially on the same level as the upper surface of the annular flange portion 82 at
is located close to the annular flange portion 82. The linear portion 126b of the stationary support plate 126
Straight guide walls 128 and 130 are fixed on both sides of the stationary support plate 126 .
On the outer peripheral edge of the arcuate portion 126a,
An arc-shaped guide wall 132 is fixed to the outer peripheral edge of the turret plate 124 and extends in an arc shape at a predetermined interval. As clearly shown in FIG. 3, the downstream end of the arcuate guide wall 132 projects beyond the downstream end of the stationary support plate 126 and onto the annular flange portion 82 of the main body 30 described above.

The operation of the container lid supply means 116 will be explained as follows. The rotating shaft 122 and the turret plate 124 fixed thereto are driven by an appropriate rotational drive source 42 (FIG. 4) such as an electric motor.
In synchronization with the rotation of the rotary support 38 in the main portion 30 described above (therefore, the rotation of the shaft 54, the inner cutting tool 78, and the annular flange portion 82), the arrow 13
It is rotated in the direction shown by 4. Container lid 2 in which weakened line 24 and vertical cut 25 are to be formed
(FIGS. 1 and 2), the stationary support plate 12 is
6 on the straight portion 126b of the turret plate 124 in an inverted state from the left to the right in FIG. After that, as the turret plate 124 rotates, arrow 1
It is conveyed in the direction indicated by 34 to the position indicated by reference numeral B in FIG. At this time, the arc-shaped guide wall 132
This prevents the container lid 2 from coming off radially outward. In the position indicated by the symbol B in FIG.
It is located on a disc-shaped receiving portion 94 of a receiving member 92 that is rotatably mounted on the receiving member 92 . Moreover, at this point, as will be described in detail later, the shaft body 5 in the main portion 30 is
4 and an inner cutting tool 78 fixed to its lower end.
starts to lower, and the inner cutting tool 78 closes the container lid 2.
It begins to be inserted inside. In this way, the container lid 2 that has been supplied to the position indicated by the symbol B is then moved to the main portion 3.
The rotation of the rotary support 38 at 0 (therefore the rotation of the shaft 54 and the inner cutting tool 78 as well as the annular flange 8
2) and is conveyed in the direction shown by arrow 44.

Next, with reference to FIGS. 4 and 6 as well as FIG. 3, the stationary outer cutting means 118 disposed in the cutting area 112 will be described. As understood from FIG. 4, the stationary base 3 in the main part 30
2 is formed with an arcuate flange 136 extending in an arc shape extending below the cutting area 112. Then, on this arcuate flange 136,
An arcuate support 138 is fixed. As clearly shown in FIG. 6, an arcuate groove 140 that is open upwardly and inwardly is formed in the inner peripheral edge of the upper surface of the arcuate support 138. As shown in FIG. Two stationary outer cutting tools are installed in this arcuate groove 140, namely, a stationary outer cutting tool 142 for through cutting located on the upstream side and a stationary outer cutting tool 144 for partial cutting located on the downstream side.
is installed. More specifically, a height-adjusting arcuate block 146 is placed on the bottom surface of the arcuate groove 140, and the stationary outer cutting tool 142 for through-cutting and the stationary outer cutting tool for partial cutting are mounted on the block 146. A tool 144 is placed. At the upstream and downstream ends of the stationary outer cutter 142 for through-cutting, a set screw 14 is inserted through the cutter 142 and the block 146 into the support 138.
8 is screwed on, thus fixing the cutting tool 142. Similarly, at the upstream and downstream ends of the stationary outer cutting tool 144 for partial cutting, the cutting tool 144
A set screw 150 is then threaded onto the support 138 through the block 146, thus securing the cutting tool 144. The inner peripheral edges of the cutting tools 142 and 144 protrude beyond the inner peripheral edges of the block 146 and the support 138, and cutting blades are formed on the inner peripheral edges (the form of the cutting blades will be described later). The height of cutting tools 142 and 144 is appropriately set by the thickness of block 146. In other words, the cutting tool 14 can be cut by using blocks 146 of different thicknesses as needed.
2 and 144 can be changed as appropriate. The amount of protrusion of the inner circumferential edge (therefore, the cutting blade) of the cutting tool 142 is uniquely defined by bringing the inner circumferential edge, that is, the rear end edge of the cutting tool 142 into contact with the side surface of the arcuate groove 140. On the other hand, regarding the cutting tool 144, the side surface of the arcuate groove 140 and the cutting tool 14
There is an arc-shaped adjustment plate 1 between the outer peripheral edge of 4, that is, the rear edge of
52 is arranged, and the amount of protrusion of the inner peripheral edge (therefore, the cutting blade) of the cutting tool 144 is determined by the adjustment arc-shaped plate 15.
It is set by the thickness of 2. As will become clear from the description that follows, the amount of protrusion of the inner peripheral edge (and therefore the cutting blade) of the cutting tool 144 is directly related to the partial depth of cut, and therefore it is desirable to be able to adjust it as necessary. However, such adjustment of the amount of protrusion can be easily accomplished by using adjusting arcuate plates 152 having different thicknesses.

Continuing the explanation with reference to FIG. 6 as well as FIG. 3, a plurality of cutting blades 154 are formed at intervals in the longitudinal direction, that is, in the circumferential direction, on the inner peripheral edge of the stationary outer cutting tool 142 for through-cutting. ing. Cutting blade 15
4 corresponds to the circumferential length of each of the slits 26 in the weakened line 24 to be formed in the container lid 2 (see also FIG. 2). A cutting blade 154a located most downstream of the cutting tool 142 and a cutting blade 154 located adjacent thereto.
b, there is an interrupted portion having a relatively long circumferential length (this interrupted portion corresponds to the high-strength bridge portion 28A in the weakened line 24). Separately formed auxiliary cutting members 156a and 156b are fixed to the interrupted portions.
Each of the auxiliary cutting members 156a and 156b has a cutting blade 1 extending substantially vertically (therefore, substantially perpendicularly to the cutting blade 154) at the leading edge thereof.
58a and 158b are formed. Cutting blade 1
58a and 158b are positioned corresponding to the vertical cut 25 to be made in the container lid 2 (see also FIG. 2). As clearly shown in FIG. 6, the cutting blade 154 is located outside the interrupted portion where the auxiliary cutting members 156a and 156b are disposed.
At the interrupted part, both side edges 1 of each cutting blade 154
Advantageously, 55 is sloped longitudinally outwardly (ie circumferentially outwardly) towards the rear.

On the other hand, a cutting blade 160 is formed on the inner peripheral edge of the stationary outer cutting tool 144 for partial cutting. In the illustrated embodiment, the cutting blade 160 is continuous except for an interruption 162 of relatively long circumferential length located at its downstream end. The interruption 162 corresponds to the high-strength bridge 28A in the weakened line 24 to be formed in the container lid 2 (see also FIG. 2). As will become clear from the explanation that follows, the cutting blade 160 of the cutting tool 144 is capable of cutting the normal bridge portion 28 (i.e., the bridge other than the high-strength bridge portion 28A) in the weakened line 24 to be formed on the container lid 2. If desired, the cutting blade 1 of the cutting tool 144 can be
60 can also be provided in a plurality, spaced apart in the circumferential direction, corresponding to the usual bridges 28 in the line of weakness 24 to be formed in the container lid 2. Furthermore, in the illustrated example, as shown in FIG.
An arcuate stationary guide wall 163 is provided on the upstream side of 2.

Referring again to FIG. 3, the ejection means 120 provided in connection with the ejection area 114 will be described. The evacuation means 120 in the illustrated embodiment consists of a pair of stationary guide walls 164 and 166 and a stationary guide plate 168. The guide wall 164 is
It extends circularly on the outside along the circular path of travel of the inner cutting tool 78 in the discharge zone 114 and then upwardly in FIG. Guide wall 16
6 is the inner cutting tool 78 in the discharge area 114.
It extends inwardly in an arc along a circular path of travel, and then upwardly in FIG. The upstream end of the guide wall 166, ie, the arcuately extending portion, is located below the annular member 102 fixed to the rotary support 38, as can be seen from FIG. This upstream end of the guide wall 166 allows the container lid 2, which has been biased relative to the inner cutting tool 78, to be moved toward the inner cutting tool 7, as will be described later.
It functions as a concentric means to make it approximately concentric with respect to 8. The stationary guide plate 168 extends upward in FIG. 3 from an upstream end (lower end in FIG. 3) of the main portion 30 adjacent to the annular flange portion 82. The upper surface of the stationary guide plate 168 is substantially at the same level as the upper surface of the annular flange portion 82 .

Next, the supply area 11 in the apparatus as described above
0, the actions in the cutting zone 112 and the discharge zone 114 will be explained.

Referring to FIG. 7 as well as FIGS. 3 and 4, as described above, the weakened line 24 and the vertical cut 25 are
The container lid 2 to be formed is placed in the supply area 110 in an inverted state.
The receiving member 9 is rotatably mounted on the annular flange portion 82 of the main portion 30, more specifically, on the annular flange portion 82 at the position indicated by the symbol B in .
It is supplied onto the second disc-shaped receiving part 94. Above position B
In this case, as shown in FIG. 7, the shaft 54 of the main portion 30 and the inner cutting tool 78 fixed to its lower end are in the highest position and located above the container lid 2. As the rotating support 38 rotates in the direction indicated by the arrow 44, the container lid 2 and the shaft 54 on the receiving member 92 move from the above position B to the position indicated by the symbol C in FIG. During this period, the shaft 54 is gradually lowered, as can be seen from FIG. 7, and the inner cutting tool 78 fixed to the lower end of the shaft 54 is inserted into the container lid 2. When the shaft body 54 is lowered to the lowest end at the position C, the lower end of the inner cutting tool 78 comes into contact with the inner surface of the top wall 4 of the container lid 2 and presses the container lid 2 against the receiving member 92. In this way, the inner cutting tool 78, the container lid 2, and the receiving member 92 are elastically brought into close contact with each other by the elastic action of the spring 90 that elastically biases the receiving member 92 upward. Thus, as described above, when the shaft body 54 and the inner cutting tool 78 fixed to its lower end are moved in the direction shown by the arrow 44 in conjunction with the rotation of the rotary support body 38,
It is caused to rotate in the direction shown by arrow 170 in FIG. Therefore, the container lid 2 and the receiving member 92 are also rotated in the direction shown by the arrow 170 in FIG. On the other hand, when the container lid 2 is moved from the above position B to the above position C, the arc-shaped stationary guide wall 163 disposed outside the movement path of the container lid 2 acts on the container lid 2, and the inside The container lid 2 is biased inward with respect to the cutting tool 78. To explain in more detail, the third
As can be clearly seen from the figure, the outer diameter of the inner cutting tool 78 is somewhat smaller than the inner diameter of the container lid 2, so that before the said guide wall 163 acts on the container lid 2, the inner cutting tool 78 There is some gap around the entire circumference between the outer peripheral surface of the container lid 2 and the inner peripheral surface of the skirt wall 6 of the container lid 2. However, when the guide wall 163 acts on the container lid 2 to bias it radially inward, the container lid 2 becomes eccentric with respect to the inner cutting tool 78, and the container lid 2 The inner peripheral surface of the skirt wall 6 is brought into contact with the outer peripheral surface of the inner cutting tool 78.

When the container lid 2 is moved from the above-mentioned position C to the position indicated by the symbol D in FIG.
is pressed against the inner peripheral edge of the stationary outer cutting tool 142 for through-cutting and the stationary outer cutting tool 144 for partial cutting,
rolling along the inner peripheral edges of the cutting tools 142 and 144;
That is, while rotating in the direction shown by arrow 170, arrow 4
It is caused to move in the direction shown by 4. Then, while the container lid 2 is rolled along the cutting tool 142, a through cut is formed in the container lid 2.

Referring to FIG. 8 together with FIGS. 3 and 6, when the container lid 2 rolls along the cutting tool 142, the cutting blade 154 formed on the inner peripheral edge of the cutting tool 142 A through cut is made in the skirt wall 6 of the container lid 2 which projects through the skirt wall 6 of the container lid 2 and projects into an annular cutting groove 80 formed in the inner cutting tool 78, thus corresponding to the arrangement of the cutting blades 154. is formed. Since a plurality of cutting blades 154 are formed on the inner peripheral edge of the cutting tool 142 at intervals in the circumferential direction, as shown in FIG. A plurality of circumferentially extending through cuts 172 are formed at intervals. Referring to FIG. 2 in conjunction with FIG. 9, the through cut 172 defines the slit 26 at the line of weakness 24 to be formed. Cutting tool 1
42, the non-cut portion 174A formed corresponding to the interrupted portion having a relatively long circumferential length between the cutting blade 154a and the cutting blade 154b is a high-strength bridge portion in the weakened line 24 to be formed. 28
Define A. Other non-cut portions 174 generated corresponding to the portions between other cutting blades 154 correspond to normal bridge portions 28 in the weakened line 24 to be formed. According to the experiments of the present inventors,
As already mentioned with reference to FIG.
When the both side edges 155 of the container lid 2 are inclined rearwardly outward in the longitudinal direction (that is, outward in the circumferential direction), the container lid 2
The through cut 172 formed in the slit 26, and therefore the circumferential edge of the slit 26, can be formed into a preferred configuration extending substantially along the radial direction of the container lid 2, as shown by the two-dot chain line in FIG. Cutting blade 15
4, the circumferential width of the non-cut portion 174 remaining between the through-cuts 172 and the circumferential edge of the through-cut 172 formed in the container lid 2, and thus the circumferential edge of the slit 26, are However, it tends to gradually become smaller toward the inside in the radial direction. The angle of inclination of both side edges 155 of the cutting blade 154 can be appropriately set according to the outer diameter and wall thickness of the skirt wall 6 of the container lid 2. The container lid 2 is the cutting tool 14
2, cutting blades 158a and 158b formed at the tips of the auxiliary cutting members 156a and 156b (FIG. 6)
Accordingly, a through vertical notch extending substantially vertically is also formed at both ends of the non-notched portion 174A, and the through vertical notch defines a vertical notch 25 (FIG. 2) in the skirt wall 6 of the container lid 2. .

Referring to FIG. 10 along with FIGS. 3 and 6, when the container lid 2 rolls along the cutting tool 144, the cutting blade 160 formed on the inner peripheral edge of the cutting tool 144 Acts on the skirt wall 6 of the container lid 2. As clearly shown in FIG. 10, the amount of protrusion of the cutting blade 160 is relatively small, and the front edge of the cutting blade 160 is located in the middle of the wall thickness of the skirt wall 6 of the container lid 2. Therefore, the cutting blade 160
acts only on the non-cut portions 174 (therefore, the bridge portions 28) remaining between the through cuts 172 (therefore, the slits 26) formed by the cutting blades 154. Thus, as shown in FIG. 11, a partial cut 176 is formed in the non-cut portion 174,
The residual cross-sectional area of the non-cut portion 174 is reduced to a required value, and the required bridging portion 28 is generated. on the other hand,
Interruption 162 present in cutting blade 160 (FIG. 6)
are arranged corresponding to the position of the non-cut portion 174A (therefore, the high-strength bridge portion 28A) shown in FIG. 11, and therefore, in the illustrated example,
No partial cut is formed in the high-strength bridge portion 28A.

Thus, in the illustrated embodiment, the stationary outer cutter 142 for through-cutting first acts on the skirt wall 6 of the container lid 2 to form the through-cut 172, and then the stationary outer cutter 144 for partial cutting is applied. acts on the skirt wall 6 of the container lid 2 to form a partial cut 176
If desired, a stationary outer cutting tool 142 for through-cutting and a stationary outer cutting tool 144 for partial cutting may be used to form
are arranged in reverse order, first the stationary outer cutting tool 144 for partial cutting acts on the skirt wall 6 of the container lid 2 to form the partial cut 176, and then the stationary outer cutting tool 142 for through-cutting acts on the skirt wall 6 of the container lid 2. It is also possible to form the through cut 172 by acting on the two skirt walls 6.

As can be understood from FIG. 7, while the container lid 2, in which the required weakening line 24 and vertical cut 25 have been formed as described above, is moved from the above-mentioned position D to the position indicated by reference numeral F in FIG. Like, shaft body 54
and an inner cutting tool 78 fixed to its lower end.
is gradually raised from its lowest position.
When the container lid 2 is moved to the point indicated by the symbol E in FIG. 3, the inner cutting tool 78, which has been gradually raised, is completely separated from the container lid 2. Thus, when the container lid 2 is moved to the above position E, the upstream end of the guide wall 166 of the ejecting means 114 acts on the container lid 2, causing the container lid 2 to move outward against the inner cutting tool 78. bias towards In this way, the container lid 2, which has been eccentric with respect to the inner cutting tool 78, is made approximately concentric with the inner cutting tool 78. The upward removal of the inner cutting tool 78 from the container lid 2 is therefore accomplished with sufficient ease. Additionally, in the illustrated embodiment, as previously mentioned with reference to FIG. A through opening 106 is formed which is somewhat smaller than the outer diameter of the container lid 2. The inner cutting tool 78 is therefore able to rise through the through opening 106, but the container lid 2 is prevented from rising;
In this way, the container lid 2 is reliably prevented from rising along with the inner cutting tool 78. The container lid 2 in position E is moved upwardly in FIG. 3 by suitable means, such as an air stream, and is thus ejected from the main portion 30 along the ejection means 114. The container lid 2 discharged along the discharge means 114 can be delivered to an appropriate site for the next process.

Although preferred embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to these specific examples, and various modifications and changes can be made without departing from the scope of the present invention. Of course there is.

[Brief explanation of drawings]

FIG. 1 is a side view, partially in section, of an example of a container lid before weakening lines and vertical cuts are formed according to the present invention. FIG. 2 is a side view, partially in cross section, of the container lid shown in FIG. 1 with weakened lines and vertical cuts formed therein. FIG. 3 is a simplified cross-sectional view (No. 4
cross-sectional view along the line - in the figure). Figure 4 shows the third
A sectional view taken along the line - in the figure. FIG. 5 is a cross-sectional view showing the receiving member and its related structure in the device of FIG. 3. FIG. 6 is a partial perspective view showing the stationary outer cutting tool and related components in the apparatus of FIG. 3; 7th
The figure is a simplified diagram showing the raising and lowering of the inner cutting tool in the apparatus of FIG. 3. FIG. 8 is a sectional view showing the operation of the stationary outer cutter for through-cutting in the apparatus of FIG. 3; 9th
4 is a cross-sectional view showing a through cut made in a container lid by a stationary outer cutter for through cutting in the apparatus of FIG. 3; FIG. 10 is a sectional view showing the operation of the stationary outer cutting tool for partial cutting in the apparatus of FIG. 3; FIG.
FIG. 11 is a cross-sectional view showing a partial cut made in a container lid by a stationary outer cutting tool for partial cutting in the apparatus of FIG. 3; 2... Container lid, 4... Top wall of container lid, 6...
Skirt wall of the container lid, 24... Weakening line of the container lid, 25... Vertical cut in the container lid, 26... Slit in the weakening line, 28... Bridge portion in the weakening line, 30... Main part of the device, 38 ... Rotating support body, 54 ... Shaft body, 78 ... Inner cutting tool, 92
. . . receiving member, 110 . Stationary external cutting tool,
144... Stationary outer cutting tool for partial cutting.

Claims (1)

[Scope of Claims] 1. A container lid having a top wall and a cylindrical skirt wall hanging down from the top wall, and at least a lower part of the skirt wall is made of synthetic resin, the lower part of the skirt wall having a circumferential direction. A method of forming a weakened line consisting of a plurality of circumferentially extending slits spaced apart from each other and a plurality of bridges remaining between the slits; a through-cutting step that creates a plurality of radially extending and circumferentially extending cuts in a lower portion of the skirt wall spaced apart from each other; and a separately fabricated portion of the through-cutting outer cutter. Separately from the through-cutting step, using an outer cutting tool, cut a section radially at the bottom of the skirt wall, at least at a major portion of the section to be attached to the plurality of bridges. a partial cutting step of generating a notch in a consistent manner; 2. The method of claim 1, wherein said through-cutting step is performed and then said partial cutting step is performed. 3. The method of claim 1, wherein said partial cutting step is performed and then said through cutting step is performed. 4. The outer cutting tool for through-cutting used in the through-cutting step has a plurality of cutting blades arranged at intervals in the longitudinal direction, and at least the front portion of both side edges of each of the cutting blades. 4. A method according to any one of claims 1 to 3, wherein the is longitudinally inclined outwardly towards the rear. 5. At least one of the plurality of bridge portions is a strong bridge portion having at least one of a circumferential width and a radial thickness larger than other bridge portions, and in the through-cutting step, Claims 1 to 4 further include forming a vertical cut extending downward from a position aligned with or close to at least one side of the strong bridge portion.
The method described in any of the paragraphs. 6. A container lid having a top wall and a cylindrical skirt wall hanging from the top wall, and at least the lower part of the skirt wall is made of synthetic resin. A device for forming a weakened line consisting of a plurality of slits extending in the direction and a plurality of bridges remaining between the slits, the device comprising a rotatably mounted support and a plurality of container lid transport means mounted on a support, the container lid transport means including an inner cutting tool rotatably mounted about its own central axis; a rotary drive source for moving the container lid conveying means through a circular movement path that sequentially passes through a supply area, a cutting area, and a discharge area; a rotation means for rotating the inner cutting tool about its own central axis; container lid supply means for supplying container lids to the container lid conveying means in the supply zone; and an upstream portion of the cutting zone. a first stationary outer cutting tool extending in an arc along the circular path of travel of the inner cutting tool at the cutting zone; a first stationary outer cutting tool extending in an arc along the circular path of travel of the inner cutting tool downstream of the cutting zone; a second stationary outer cutting tool fabricated separately from the first stationary outer cutting tool; and container lid ejection means for ejecting the container lid from the container lid conveying means in the ejection zone. , the container lid supplied to the container lid conveying means in the supply zone is fitted onto the inner cutting tool, and in the cutting zone, the container lid is fitted onto the first stationary outer cutting tool and the second stationary outer cutting tool are rolled into abutment such that one of the first stationary outer cutting tool and the second stationary outer cutting tool radially penetrates the lower portion of the skirt wall at circumferentially spaced intervals. and a plurality of cuts extending in the circumferential direction are generated, and the first
The other of the stationary outer cutting tool and the second stationary outer cutting tool partially cuts a portion of the lower portion of the skirt wall, viewed in the radial direction, at least at a majority of the portions to be connected to the plurality of bridges. A device characterized in that a notch is generated in the. 7. The first stationary outer cutting tool and the second stationary outer cutting tool extend along the outer periphery of the travel path of the container lid conveying means and have cutting blades on the inner periphery. The device described. 8. One of the first stationary outer cutting tool and the second stationary outer cutting tool has a plurality of longitudinally spaced cutting blades, each of the cutting blades having a 8. A device according to claim 6 or 7, wherein at least the front portions of the side edges are sloped longitudinally outwardly towards the rear. 9 at least one of the spacings between the plurality of cutting blades in one of the first stationary outer cutting tool and the second stationary outer cutting tool is a wide spacing that is larger than the other spacings; One of the first stationary outer cutting tool and the second stationary outer cutting tool is also provided with a longitudinal cutting blade extending substantially perpendicular to the longitudinal direction in alignment with or adjacent to at least one side of the wide spacing. 9. The apparatus of claim 8, wherein the longitudinal cutting blade produces a longitudinal cut in a lower portion of the skirt wall. 10 The container lid conveying means includes a receiving member rotatably mounted below facing each of the inner cutting tools, each of the inner cutting tools is mounted so as to be able to rise and fall, and the inner cutting tool Each of the tools is provided with lifting means for raising and lowering the inner cutting tool as required as the container lid conveying means is moved along the circular path of travel, and the tool is provided with lifting means for raising and lowering the inner cutting tool as required when the container lid conveying means is moved along the circular path of travel. In this case, the container lid is placed upside down on the receiving member by the container lid supplying means, and then the inner cutting tool is lowered and inserted into the container lid, so that the container lid is attached to the inner cutting tool. At the same time, the top wall of the container lid is pressed against the upper surface of the receiving member by the lower surface of the inner cutting tool, and in the cutting area, the inner cutting tool is in a lowered state. 10. A device according to any one of claims 6 to 9, wherein the inner cutting tool is raised and removed from the container lid until it reaches the discharge area. 11 The outer diameter of the inner cutting tool is smaller than the inner diameter of the container lid, the container lid is eccentric with respect to the inner cutting tool in the cutting zone, and the container lid is placed eccentrically with respect to the inner cutting tool in the cutting zone, and 11. The apparatus according to claim 10, further comprising concentric means for making the container lid substantially concentric with the inner cutting tool upstream of the inner cutting tool. 12 The concentric means defines a guide surface extending in an arc along the circular path of travel of the container lid conveying means on opposite sides of the first stationary outer cutting tool and the second stationary outer cutting tool. 12. The device of claim 11, comprising a guide member having a guide member.