JP2015120546A - Container lid and production method of container lid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a safe container lid where: accidents such as lid jumping and the like are prevented by releasing internal pressure when the internal pressure of the container is significantly increased; the releasing of the internal pressure at an internal pressure value below a predetermined value does not occur; discomfort is not given to the fingers of a user; and injury is not caused at the fingers of the user.SOLUTION: A first annular bead 112 and a second annular bead 113 are disposed from above at a top surface wall 120 side from the screw formation region 111 of the skirt wall 110 of a container lid 100. At least one slit 115 having a predetermined length in a circumferential direction is disposed in a groove part 114 between the first annular bead 112 and the second annular bead 113.

Description

  The present invention relates to a container lid attached to a container mouth and a method for manufacturing the same, and more particularly, a container lid that releases an internal pressure to prevent an accident such as a lid jump when the internal pressure of the container is significantly increased, and a method for manufacturing the same. About.

2. Description of the Related Art Conventionally, a container lid formed of a thin metal plate has been widely used practically as a container lid attached to the container mouth.
A typical container lid has a circular top wall and a cylindrical skirt wall that hangs from the top wall to the periphery. A synthetic resin liner is disposed on the inner surface of the top wall, and the upper surface is open. It is applied to a container formed of a thin metal plate having a cylindrical mouth portion, glass, or synthetic resin.
An external thread is formed on the outer peripheral surface of the mouth of the container. When the container lid is attached to the mouth of the container and the mouth is sealed, the container lid is fitted on the mouth and the skirt wall is A female screw corresponding to the male screw of the mouth is formed in the screw forming region (see, for example, Patent Document 1).

Containers that are sealed by applying such container lids, or containers that are once opened and then screwed back into the container lid to seal them, for example, when they are exposed to high temperatures or when the contents are fermented, spoiled, etc. In addition, when the contents are a carbonated beverage or the like and a strong vibration is applied, the internal pressure of the sealed container may increase significantly.
At that time, the container lid could not withstand the pressure, causing the lid to fly, and there was a risk of damaging surrounding people and objects, or contaminating the surroundings with the scattered contents.
In order to prevent such an accident, a so-called explosion-proof cap in which a slit is provided on the top wall side from the screw formation region of the skirt wall is known.
This slit does not play the role of the range of use under normal circumstances, but only when the internal pressure rises abnormally under the unexpected conditions as described above, it will be deformed and released with the deformation of the top wall. With this function, part of the seal point of the liner that is in close contact with the container mouth is broken to release the internal pressure, preventing accidents such as jumping on the lid. (For example, see Patent Documents 2 and 3).

For example, in a container lid known from Patent Document 2, a knurl is formed on the top wall side from a screw formation region in which a skirt wall screw is formed, and the upper edge of the recess of the knurl (the knurl portions 6 and 7) is cut into a cut surface. As shown, slits (6a, 7a) are formed.
Further, in the container lid known in Patent Document 3, a knurl (uneven shape portion) is formed on the top wall (8) side from the screw formation region (main portion 14) where the screw of the skirt wall (10) is formed, A slit is formed above the knurl.

Japanese Utility Model Publication No. 01-154146 Japanese Patent Laid-Open No. 2003-155052 Japanese Patent No. 4727162

In a container lid provided with an explosion-proof function slit for releasing a known internal pressure, a part of the cut edge of the slit exists in an outer peripheral position where there is a possibility that the container lid may be accidentally touched when the user grasps the container lid. .
For this reason, there exists a possibility that the cutting edge of a slit may give an unpleasant feeling to a user's finger, or may injure a user's finger by the cutting edge of a slit.
In order to suppress such a situation, it is conceivable that the cut edge of the slit is processed smoothly or deformed inward.

However, the container lid often has slight dents and deformations during handling such as supply when being wrapped around the container mouth, and if the dents or deformations occur near the slit cutting edge, Since the cutting edge of the slit may protrude to the outer peripheral side as the mouthpiece is tightened, the above-described problem cannot be solved by processing only the cutting edge.
Furthermore, it is necessary to form a slit in the shape and dimensions for ensuring the release of the internal pressure only when the container internal pressure exceeds a predetermined value. Due to the deformation of the slit, the internal pressure is released at an internal pressure value lower than a predetermined value, and there is a problem that the internal pressure cannot be released in an appropriate range.

  Therefore, the present invention solves the above-described problems, and when the internal pressure of the container is remarkably increased, the internal pressure is released to prevent an accident such as a cover jumping, and the internal pressure is set at a predetermined internal pressure value or less. It is an object of the present invention to provide a safe container lid that does not open and does not cause discomfort to the user's fingers or injure the user's fingers.

A container lid according to the present invention is a container lid having a top wall and a skirt wall that hangs down from the top wall to the periphery. One annular bead and a second annular bead are provided, and the groove between the first annular bead and the second annular bead is provided with at least one slit having a predetermined length in the circumferential direction, thereby Is a solution.
A method for manufacturing a container lid according to the present invention is a method for manufacturing a container lid having a top wall and a skirt wall that hangs down from the top surface wall to the periphery. On the face wall side, the groove forming tool is pressed from the outside to form the first annular bead, the second annular bead and the groove between them, and the slit forming tool is pressed into the groove from the outside The said subject is solved by forming the slit of predetermined length in a direction.

According to the container lid of the first aspect, the first annular bead and the second annular bead are provided from the upper side to the top surface wall side from the screw forming region where the screw of the skirt wall is formed. By providing at least one slit of a predetermined length in the circumferential direction in the groove between the two annular beads, the slit is deformed and released along with the deformation of the top wall when the internal pressure abnormally increases, As a result, a part of the seal point of the liner that is in close contact with the container mouth is broken to release the internal pressure, so that an accident such as a lid jump can be prevented.
In addition, since the cutting edge of the slit exists in the groove part, when the user grips the container lid, the fingers are applied only to the outer peripheral parts of the first annular bead and the second annular bead, and the cutting edge of the slit provided in the groove part Since the finger does not touch the finger, the user's finger can be prevented from being uncomfortable or injured.
Furthermore, since the first annular bead and the second annular bead protrude from the groove portion, dents and deformation occur in the first annular bead and the second annular bead during handling when the container lid is applied to the container mouth. Even if the groove portion is not dented or deformed, the cutting edge of the slit provided in the groove portion does not protrude to the outer peripheral side with the tightening, and the user does not touch the finger.
And, it becomes difficult for deformation of the slit to occur with tightening or due to external force or impact after winding, and the internal pressure is released more reliably at a predetermined value to prevent accidents such as jumping of the lid. be able to.

According to the configuration of the second aspect of the present invention, the second annular bead is formed with a knurled portion having a concavo-convex portion in the circumferential direction, thereby preventing slippage when the user grips it. It becomes possible.
In addition, the knurl is formed at a position away from the slit, and the cut edge of the slit can be prevented from protruding to the outer peripheral side.
According to the third aspect of the present invention, the knurl is provided at the screw forming region side of the second annular bead, so that the knurl is further formed at a position away from the slit, and the tightening is performed. Thus, it is possible to more reliably prevent the cut edge of the slit from protruding to the outer peripheral side.

According to the configuration of the present invention, since the slit can receive the force equally in the circumferential direction at the time of winding or the like, deformation of the slit at the time of winding or after winding is further generated. It is possible to prevent accidents such as jumping of the lid by reliably releasing the internal pressure.
According to the configuration of the fifth aspect of the invention, since the maximum outer diameter of the first annular bead and the second annular bead is the same diameter, the bottom of the groove is equal to both the first annular bead and the second annular bead. Thus, when the user holds the container lid, it is possible to more reliably prevent the finger from touching the cut edge of the slit.
According to the configuration of the sixth aspect of the present invention, it is necessary and sufficient for the slit to be surely opened when the internal pressure is abnormally increased, and deformation of the slit occurs during or after winding. Since the length is difficult, it is possible to prevent accidents such as jumping of the lid by reliably releasing the internal pressure when the internal pressure exceeds a predetermined internal pressure while securely sealing.

According to the container lid manufacturing method of the present invention, the internal pressure of the container can be changed without changing the inner tool only by going through a process in which only the tool pressed from the outside of the skirt wall is made different. Easily manufacture container lids that release internal pressure to prevent accidents such as jumping of the lid when it rises significantly, and that do not cause discomfort to the user's fingers or injure the user's fingers. Is possible.
In addition, the slit forming tool is not sheared jointly with the opposing tool, but can be formed by pushing the tip of an acute angle from the outside as a single unit, so that all the cutting edges of the slit are inside. It is possible to manufacture a container lid that does not unpleasantly injure the user's fingers or injure the user's fingers.
According to the structure of this Claim 8, it becomes possible to perform formation of a slit and formation of a knurl simultaneously, and it can manufacture more easily.

The perspective view of the container lid which is one Embodiment of this invention. The half section side view of the container lid which is one embodiment of the present invention. The half cross section side view at the time of winding to the container of the container lid which is one Embodiment of this invention. Explanatory drawing of the manufacturing process of the groove part of the container lid which is 1 embodiment of this invention. Explanatory drawing of the manufacturing process of the slit of a container lid which is one Embodiment of this invention, and a knurl.

Below, the structure of the container lid 100 which is one Embodiment of this invention is demonstrated based on drawing.
As shown in FIGS. 1 to 3, the container lid 100 includes a top wall 120 and a skirt wall 110 that hangs down from the top wall 120 to the periphery, and includes a screw forming region 111 in which a screw of the skirt wall 110 is formed. A first annular bead 112 and a second annular bead 113 are provided on the top wall 120 side from above.
As shown in FIGS. 2 and 3, the maximum outer diameters of the first annular bead 112 and the second annular bead 113 are formed to have substantially the same diameter, and are formed in the groove 114 between the first annular bead 112 and the second annular bead 113. Are provided with three slits 115 extending in the circumferential direction.
On the screw forming region 111 side of the second annular bead 112, a plurality of recesses are provided at predetermined intervals, and a knurl 116 that forms an uneven portion in the circumferential direction is formed.

As shown in FIG. 3, a synthetic resin liner 101 is adhered to the back surface of the top wall 120 so as to be in close contact with the container mouth.
Further, a tamper evident portion 117 is provided below the screw forming region 111 of the skirt wall 110.
The tamper evident portion 117 may have any structure.
1 and FIG. 2 shows a state before first mounting on the container mouth, and the screw forming region 111 is a female screw corresponding to the male screw of the container mouth when being mounted on the container mouth. It is pressed and deformed from the outside so as to form.
FIG. 3 shows the container lid 100 after being wrapped around the container C. The screw forming region 111 is formed in the male screw shape of the container C, and the lowermost end of the tamper evident portion 117 is on the container C side. It is deformed by caulking.
Further, when the first annular bead 112 is pressed and deformed from the outside, the inner liner 101 is brought into close contact with the opening of the container C with a predetermined pressure, and the sealing performance of the container C is ensured.

Specifically, for example, it is of the same 38 mm diameter standard as the conventional container lid, and in the above embodiment, the bottom of the groove 114 is located at a distance of 2.6 mm from the top wall 120. A first annular bead 112 and a second annular bead 113 were provided, and three slits 115 were provided at equal intervals on the bottom of the groove 114 with a circumferential length of 11.9 mm.
Each slit 115 has a length corresponding to three concave portions and two convex portions of the knurl 116, and is formed so that the concavo-convex portions of the knurl 116 are arranged symmetrically as viewed from the center in the circumferential direction of the slit 115. ing.
When such a container lid 100 is tightened under the same conditions as a conventional container lid, and the first annular bead 112 is pressed from the outside to bring the liner 101 into close contact with each other, there is no influence of dents or the like and the container C is surely secured. The container lid 100 can release the internal pressure at the required internal pressure (set to 0.6 MPa in this embodiment), and the cutting edge of the slit 115 does not touch the user's hand. And was able to.
If the slit length is less than 25% of the diameter of the container lid, there will be a case where the lid does not open at a predetermined internal pressure and the lid will fly off. Due to the deformation of the slits, there was a case where it was opened at an internal pressure value lower than a predetermined value.

A method for manufacturing the container lid 100 according to one embodiment of the present invention configured as described above will be described with reference to FIGS. 4 and 5.
After forming a simple cylindrical skirt wall 110 from a thin metal plate, the container lid 100 is pressed by a pressing tool from the inside and outside to be molded into the final shape before winding as described above.
First, in the first step, an inner first annular bead forming tool 141, an inner second annular bead forming tool 142, an inner knurl forming tool are arranged in order from the top wall 120 side to the inside of the simple cylindrical skirt wall 110. The inner pressing tool having 143 is inserted, and the groove forming tool 131 and the second annular bead forming tool 134 are pressed from the outer side toward the inner pressing tool side while rotating the container lid 100. As shown in FIG. 3, the first annular bead 112, the annular groove 114, and the second annular bead 113 are formed from the top wall 120 side.

Next, in the second step, the inner pressing tool having the inner first annular bead forming tool 141, the inner second annular bead forming tool 142, and the inner knurl forming tool 143 is formed while being inserted. Simultaneously press the slit forming tool 132 from the outside of the groove 114, the knurl forming tool 133 from the outside of the lower half of the formed second annular bead 113, and the presser tool 135 from the outside below the second annular bead 113. Thus, as shown in FIG. 5, the slit 115 and the knurl 116 are formed.
The slit forming tool 132, the inner knurl forming tool 143, and the knurl forming tool 133 are each appropriately rotated with respect to the rotation of the container lid 100 according to the number and length of the slits 115 required and the interval between the irregularities of the knurls 116. Thus, it is configured to intermittently press-mold.
The tip of the slit forming tool 132 is formed into a sharp double-edged cutter shape with an angle of 15 ° on both sides from the center line, and can be formed by pushing in without slitting together with the opposing tool. Has been.

Below the second annular bead 113 (right direction in FIGS. 4 and 5), the screw forming region 111 is sandwiched from the inside and outside, and functions as a guide for rotating the container lid 100 for molding, and further below. In a further right direction from the illustrated range, the tamper evident portion 117 is formed by an appropriate tool in parallel with the aforementioned steps.
Further, the groove forming tool 133 and the slit forming tool 132, the second annular bead forming tool 134 and the knurl forming tool 133 are respectively integrated to form the first annular bead 112, the groove 114, the slit 115, the second annular bead 113 and the knurl 116. May be simultaneously molded in one step.

DESCRIPTION OF SYMBOLS 100 ... Container lid 101 ... Liner 110 ... Skirt wall 111 ... Screw formation area 112 ... 1st annular bead 113 ... 2nd annular bead 114 ... Groove 115 ... Slit 116 ・ ・ ・ Nar 117 ・ ・ ・ Tamper evident portion 120 ・ ・ ・ Top wall 131 ・ ・ ・ Groove forming tool 132 ・ ・ ・ Slit forming tool 133 ・ ・ ・ Nar forming tool (outward)
134 ・ ・ ・ Second annular bead forming tool (outside)
135 ・ ・ ・ Presser tool (outside)
141 ... inner first annular bead forming tool 142 ... inner second annular bead forming tool 143 ... inner knurling tool C ... container

Claims (8)

A container lid having a top wall and a skirt wall hanging from the top wall to the periphery,
A first annular bead and a second annular bead are provided from the upper side to the top surface wall side from the screw forming region where the screw of the skirt wall is formed,
A container lid, wherein a groove between the first annular bead and the second annular bead is provided with at least one slit having a predetermined length in a circumferential direction.   2. The container lid according to claim 1, wherein the second annular bead is formed with a knurl provided with an uneven portion in a circumferential direction.   The container lid according to claim 2, wherein the knurl is provided on a screw forming region side of the second annular bead.   3. The container lid according to claim 1, wherein the slit is formed so that the knals are arranged symmetrically when viewed from the center in the circumferential direction of the slit.   The container lid according to any one of claims 1 to 4, wherein a maximum outer diameter of the first annular bead and the second annular bead is the same.   The container lid according to any one of claims 1 to 5, wherein a length of the slit in a circumferential direction is 25 to 50% of a diameter of the container lid. A method for producing a container lid having a top wall and a skirt wall hanging from the top wall to the periphery,
Pressing the groove forming tool from the outside to the top wall side from the screw forming region where the screw of the skirt wall is formed, to form the first annular bead, the second annular bead and the groove between them,
A method for manufacturing a container lid, comprising: forming a slit having a predetermined length in the circumferential direction by pressing a slit forming tool from the outside in the groove.   The knurling tool is formed by pressing the knurling tool from the outside to the second annular bead at the same time as pressing the slitting tool to form a knurled portion having a concavo-convex portion in a circumferential direction. A method for producing a container lid.

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