JPS62122964A - Sealing cover made of plastic - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a plastic sealing lid for containers, especially bottles.

(b) Prior art and its problems For many years, metal crowns have been used as sealing lids for containers, and these crowns can be made of various materials such as cork, rubber, thermosetting plastics and thermoplastics, etc. It is lined with. A number of representative crowns lined with such materials are disclosed in U.S. Pat. No. 1.486,9.
No. 37, No. 2,548.305, No. 2,654.913, No. 2,684.774, No. 2,688.776, 2,
696.318, 2,823.422, 2,834
．． No. 498, No. 2,840,858, 2.952.03
5, 3,183.144, 3,278.985 and 3,300.072.

Recently, the benefits of plastic crowns or sealing lids have been recognized. However, physical properties of glass such as melt plastic deformation temperature, elasticity during molding,
Due to impact compressive strength and freezing temperatures, problems arise in forming plastic sealing lids that are different from those encountered in forming metal sealing lids.

For example, in the case of plastic sealing lids according to the prior art, the wall thickness is limited to a limited range.

■The wall is sufficiently thin so that the threaded peripheral wall part of the Chitomi 11 lid can be removed and bent in the axial direction from the plunger X7.
Moreover, it must be thick enough to support the required thread size and shape.

The threads on the circular plastic sealing cap must have a certain degree of taper to allow the threaded jacket to be removed and deflected from the plunger.

With six plastic sealing lids, such as the Bolibu O pyrene sealing lid, the sealing lid has low impact current and Celsius
Fails drop tests at temperatures ranging from 32° to 40° Fahrenheit. On the other hand, conventional plastic sealing lids require a very wasteful amount of time to manufacture. In addition, it contains high-pressure drinking water, etc.
Plastic lids did not provide a sufficiently effective seal.

The present invention overcomes the above-mentioned problems of the prior art, and aims to provide a plastic sealing lid that is extremely easy to manufacture and can effectively seal a container. It is something.

(c) Means for solving the problem According to the present invention, there is provided a top wall, an annular peripheral wall having a thread on the inner surface and hanging from the top wall, and a connection between the top wall and the thread. a plastic cap having an annular backing retaining lip extending inwardly from the annular circumferential wall in between; and a plastic cap adjacent to the top wall and located within the plastic cap. Equipped with a sealed backing made of deck,
The sealing backing includes an annular seal engaged and retained by the Iz-shaped backing retaining lip, the annular seal having a generally inwardly directed seal for sealingly engaging the container. and the sealing backing has a front surface, and the sealing backing is the plastic.
formed by compression molding within a tube and including a central portion and said annular sealing portion, said annular backing retaining lip retaining said plastic sealing backing during said compression molding. In each plastic fixture 14 with a molded surface, a theft indicator band is removably connected to the circumferential wall portion of the plastic cap by a plurality of spaced apart frangible portions; There is provided a PlusNac'FJ sealing lid, characterized in that a plurality of protrusions spaced apart from each other are integrally protruded on the inner surface of the wall part, and the sealing backing is engaged with the protrusions. be done.

In the above-described configuration, the tamper-indicating band serves to determine whether the sealing lid has been tampered with, and the protrusion serves to securely retain the sealing backing within the plastic cap.

(d) Examples Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, a plastic sealing lid 100 closes and seals the mouth of a container 102 filled with a liquid, such as a carbonated beverage. The seal M1oO has a resilient plastic cap 104, often referred to as a crown, and a resilient, fluid-impermeable plastic sealing backing 106. plastic gap 10
4 is preferably made from a moldable thermoplastic material such as polypropylene, polyethylene, etc., although other materials can be used. Sealing backing 106 is preferably made from a moldable thermoplastic material such as polyvinyl chloride (PVC), although other backing materials can also be used, such as ethylene vinyl acetate (EVA).

To increase the strength of the plastic cap 104, the cap 104 includes a helical molecular arrangement, ie, HEL! There is a screwed plastic part forming a lυ-oriented molecule 108. This helical arrangement provides the cap with greater hoop strength and crack resistance than gaps formed without the helical arrangement. The turn-molded plastic material provides good impact strength and the cap is 0 to 4° Celsius (32° to 4° Fahrenheit
It can pass the drop test in the cold n1 temperature range (0°).

Preferably, cap 104 has a unitary structure and is made from polypropylene homopolymer. All parts of the plastic cap 104 are integrally connected to each other. The cap 104 has “1 wall portion 110 and this top wall portion 1
There is an annular peripheral wall portion 112 that hangs down from 10. The top wall portion 110 has a generally flat outer surface 110a and an inner surface 110b. Top wall portion 110 and peripheral wall portion 112
A circular edge 110C formed where the two intersect is rounded.

As shown in FIG. 6, the peripheral wall 112 has internal threads 114 and an inwardly extending annular backing retention lip 116 that provides an annular seal 106a of the backing 106. A surface is formed which holds the backing 106 during the backing molding process. As will be described later, the annular sealing portion 106a suitably seals all irregularly shaped portions such as bulges and irregularities at the mouth of the container. The lip 116 is inclined and the top wall 11
It converges radially inward from 0.

The outer surface of the peripheral wall 112 includes circumferentially spaced vertical ribs 120 to facilitate finger 1146 removal of the cap 104. The rib 120 extends to a lower end 124 remote from the top wall 110.

The lower end 124 has an inwardly slanted annular shoulder 126 forming a circumferential wall of this end.

After the lid 100 has been inserted and screwed into the container 102, the lower end of the peripheral wall 112 is provided with a heat-shrinkable removable Theft indicator band 128 is connected by a plurality of frangible parts 130. This stealing display band 1
28 is formed into a truncated conical band that is offset radially inward from the peripheral wall portion 112 and has an inner diameter smaller than the inner diameter of the peripheral wall portion 112 at the tip. This thief indication band 128 is stretched and expanded to
The cap 104 can be inserted onto the container 102 after being shaped into a cylinder with an inner diameter approximately equal to the inner diameter of the container 102 .

The cylindrical band 128 is elastic and returns to its original truncated conical shape when reheated.

After the sealing lid 100 is inserted and screwed into the container 102,
Theft indicator band 128 is heated, causing the band 128 to contract around and engage the neck of the container. When the sealing lid 100 is screwed back and the mouth of the container 102 is opened, the theft indication band 12
8 is torn at the round part 130. In the preferred embodiment, some of the plurality of fragile areas 130 are more competitive than others, so seal! When 1100 is removed from the container, the tamper-evident indicator band 128 breaks into one or more pieces but remains connected to the sealing lid 100 by the thickened portion. In some cases, the frangible portions 130 may all have the same thickness and be scored only horizontally so that the tamper-evident band 128 remains on the container 102 when the seal 1100 is removed.

Cap 104 has a plurality of protrusions 132 that interengage with sealing backing 106 to provide a secure mechanical relative connection between sealing backing 106 and cap 104 . A protrusion 132 extends vertically from the inner surface 110b of the top wall 110 to a position (as viewed in FIG. 1) above the annular backing retention lip 116 of the cap 104. As shown in FIGS. 2 through 5, the protrusions 132 are arranged spaced apart from each other in a grid or matrix pattern to form a plurality of spaces 134 for receiving the plastic forming the sealing backing 106 therebetween. do. This space 134 and the protrusion 1
32 is surrounded by a peripheral wall portion 112.

Each of the projections 132 (FIGS. 3-5) is formed from a generally upright column 136. The column 136 is provided with a head 138 remote from the top wall 110 of the cap 104. In the illustrated example, the column 136 has a generally square cross section.

In the process of forming the protrusion 132, the head 13 of the column 136
8 (FIGS. 3 to 5) is formed by compression and heating into a mushroom shape with a lateral extension 140 of the column 136. The overhang 140 allows the protrusion 13
A mechanical interconnection occurs between 2 and the sealing backing 106. The retention strength of the projections 132 and the strength of the mechanical bond between the sealing backing 106 and the projections 132 are proportional to the diameter of the projections 140 of the projections 132, the number of projections 132, and the spacing between the projections 132. Certain number of protrusions 132
In this case, increasing the diameter of the serrations 140 increases the peel strength of the sealing backing. Therefore, by changing the size of the overhang, the peel strength can be reduced to 0.
You can change the weight from 9Kg to 2.7Kg as required. Maximum peel strength between the protrusion 132 and the sealing backing 106 is obtained when the protrusion overhangs 140 contact each other.

The plastic sealing backing 106 has an annular sealing portion 1
A disk-shaped central portion 106b (FIG. 1) is provided which is connected to 06a and surrounded by this sealing portion 106a. The central portion 106b engages the inner surface 110b of the top wall portion 110 and lies below the head 138 of the projection 132 (in FIG. 1) and overlies the projection 132 by 1”. Inner surface 110b of wall portion 110 and lip portion 116
is constrained by the space between. The outer surface of the sealing portion 106a has a rounded lower edge portion 142 (FIG. 6), which is shaped to fit tightly into a rounded corner connecting the top wall portion 110 to the peripheral wall portion 112. are doing. In addition, the sealing part 1
06a is a frusto-conical portion 14 that slopes and converges radially inwardly from the Ifi wall 110 to engage the lip 116.
It has 4.

The inner surface of the sealing portion 106a includes a vertical sealing surface 146;
There is a frusto-conical sealing surface 148 extending radially outwardly from this sealing surface 146 at an angle. Sealing surface 148
The outer surface of the mouth of the container is elastically sealed 14, and irregularities such as bulges and irregularities in the mouth are covered to completely seal 14 fluid-tightly. If a thermoplastic sealing backing 106, such as an EVA backing, is used, the sealing backing 106 is heated and thermally bonded to the protrusion 132 (FIG. 5) during the compression molding backing process. be done.

This provides thermal bonding in addition to the mechanical interconnection provided by projections 132 (FIG. 5). In other 44I31s, such as PVC, the sealing backing 106 is not thermally bonded to the sleeve when compression molded and heated, but is mechanically held firmly by the mushroom head 138.

Advantageously, the retention strength of the protrusion 132 with the mushroom-shaped head 138 provides a tight mechanical interconnection between the key A7 knob 1o4 and the sealing backing, so that the cap The sealing backing can be molded without heating the cap, or at least the part of the cap without protrusions, to its melt plastic deformation temperature, thereby minimizing the distortion of the cap A7 when forming the sealing backing. It becomes possible to suppress it.

Other shaped heads or flared protrusions may also be used to provide mechanical interconnection with the sealing backing.

The plastic sealing lid 150 shown in FIG.
It is the same as the riloo shown in FIG. 1, except that 2 is meltable, cylindrical, and has no overhang. Protrusion 15
2 (FIG. 7) each have a generally flat end 154 with a circular edge 156, which end 154 forms at least a portion of the meltable heat concentration zone and which is connected to the sealing backing. 1' during the molding process! When the U backing 106 is compression molded and heated within the cap 104, it is thermally fused and bonded to the sealing backing 106 (FIG. 6). Sealing backing 106 by thermal bonding between backing 106 and protrusion 152
A thermal interconnection occurs between the cap 104 and the cap 104 .

Preferably, the other portions of the cap 104 are kept in a cold RJI condition so that the protrusion can be heated to its melt plastic deformation temperature so that it can be fusion bonded to the sealing backing. The shape and placement of the meltable protrusions 152 is such that distortion of the cap due to heat during molding of the sealing backing is minimized.

The plastic seal 13 shown in FIG. 8 is shown in FIGS. 6 and 7 except that the meltable projections 162 are pyramid-shaped and the bases 164 of the projections 162 in each row 166 are interconnected. It is the same as the lid 150. Each protrusion 16
The apex 168 of 2 provides a possible heat concentration area 170 for melting, which is used for sealing and during the molding process when the sealing backing is compression molded and heated in the kettle. It becomes thermally fused to the plastic that forms the pad. The meltable pyramidal protrusion 162 can be heated to its melt plastic deformation temperature so that it can fuse to the sealing backing 106, while the other parts of the cap can be kept cool so that the sealing backing 106 can be molded. At times, distortion of the cap 104 is minimized. The shape and placement and high thermal conductivity of the pyramidal projections 162 allows the caps with the pyramidal projections 162 to remain cooler than the caps with the cylindrical projections 152 during molding of the sealing backing. I believe that it is.

A pyramid-shaped projection having a radius at the apex of approximately 0.005 n (0,002 in.) is made of 0.032 c IR (0.01 in.) formed of 50 mesh stainless steel screen.
It was found to have the same adhesion (thermal bond strength) to the sealing backing as a cylindrical protrusion with a diameter of 3 inches.

The prior art sealing lid without protrusions has an adhesive force (holding strength) of only 115 between the pyramid-shaped protrusion and the cylindrical protrusion.
I could only get a moderate amount of adhesive strength.

As will be apparent to those skilled in the art, meltable protrusions having a square shape can be used in accordance with the principles of the present invention.

Although the embodiments of the present invention have been illustrated and described above, various changes and modifications may be made without departing from the scope of the present invention! It is possible to do so without going crazy.

As described above, according to the present invention, the plastic sealing backing can be securely and firmly held within the plastic cap, and a thief-indicating band can also be provided.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing a plastic sealing lid according to an embodiment of the present invention screwed into the mouth of a container, and FIG. 2 is an enlarged partially cutaway bottom view showing the inner surface of the cap. 3 is a cross-sectional view of the top wall of the key 7 knob, and a perspective view showing some of the protrusions on a very enlarged scale; FIG. 4 is a sectional view of some of the protrusions of the gear A 7 knob; 6 is a cross-sectional view similar to FIG. 4, but showing a sealing backing attached to the protrusion; FIG. 6 is a plastic material having a meltable cylindrical protrusion according to another embodiment of the present invention; 7 is a greatly enlarged perspective view of some of the meltable cylindrical protrusions of the lid of FIG. 6; FIG. 8 is a further embodiment of the invention; FIG. FIG. 3 is a greatly enlarged perspective view of an example fusible pyramidal protrusion; 100.150...Plastic sealed lid, 1°4.
...Plastic cap, 106...Plastic sealing backing, 106a...Annular sealing part, 10
6b...Central part, 110...Top wall part, 110b...
-Inner surface, 112... Peripheral wall part, 114... Screw thread, 1
16... Backing holding lip-shaped part, 128... Stealing indication band, 130... Fragile part, 146.148...
Sealing surface, 132.152.162...Protrusion.

Claims (1)

[Claims] A top wall (110), an annular peripheral wall (112) having a thread (114) on its inner surface and hanging from the top wall, and a space between the top wall and the thread a plastic cap (104) having an annular backing retention lip (116) extending inwardly from the annular circumferential wall at and located within the plastic cap adjacent to the top wall; a plastic sealing backing (106), the sealing backing having an annular sealing portion (106a) engaged and retained by said annular backing retention lip (116). the annular seal has a generally inwardly facing sealing surface (146, 148) for sealingly engaging the container, and the sealing backing (106) is attached to the plastic cap (106).
04), and includes a central portion (106b) and the annular sealing portion (106a), and the annular backing retaining lip (116) is formed by compression molding within the compression molding. A plastic sealing lid (100, 1
In 50), a theft indicator band (128) is removably coupled to the peripheral wall (112) of the plastic cap (104) by a plurality of spaced apart frangible portions (130); Moreover, the inner surface (
110b) includes a plurality of spaced apart protrusions (132,
152, 162) are integrally protruded, and the sealing backing (106) is connected to the protrusions (132, 152, 162).
a plastic sealing lid, characterized in that the lid is engaged with a plastic sealing lid;