JP2000053153A - Resin cap - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily put a cap, and to provide excellent easy-unsealability and hermetical sealability by forming at least a part of slits extending toward a top plate part from a lower part of a skirt part over a projection part for engagement on the skirt part on both sides of a knob part for unsealing so that the slits are inclined by a specified angle. SOLUTION: A cap comprises a top plate part and a skirt part suspended from its outer circumference, and a projection part 6 for engagement (61, 62,...) to be engaged with a jaw part on the outer circumferential side of a container mouth part is formed on an inner circumferential surface of the skirt part, and an inner ring to be engaged with an inner circumferential side of the container mouth part is projected from the top plate part. At least one pair of slits 10 extending to the top plate part 2 from the lower part of the skirt part over the projection part for engagement are formed on both sides of a knob part 9 for unsealing on the outer circumferential side of the lower part of the skirt part so that the slits are inclined toward the knob part 9 from a line (a) in the radial direction passing its inner end part by a specified angle θ(approximately 20-70 deg.). In addition, a pair of second slits 11 are formed with intervals from the slits 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin cap having both a sealing property and an easy opening property, and more particularly, to a cap for an infant, an elderly person, and even a sick person. The present invention relates to a resin cap capable of effectively preventing seal destruction due to lifting of a cap even when an internal pressure rises due to temperature or the like.

[0002]

2. Description of the Related Art Resin caps can be integrally molded.
Since it has excellent moldability and flexibility, it can be fixed to the container mouth by a stoppering operation, and has been widely used in various forms.

[0003] Various resin caps having excellent sealing properties and excellent opening properties that can be easily removed from the mouth of the container without using tools have already been proposed. As an example using the combination of the inner ring and the score, Jikken 47-1310
No. 9 discloses an inner plug portion 1 provided in close contact with a bottle mouth.
And a lid having a skirt portion 2 fitted to the outer peripheral side surface of the bottle, a knob portion 4 is protruded from a part of a lower end of the skirt portion 2, and a symmetrical position on the inner side wall of the skirt portion with the position where the knob piece 4 is attached. A thick ridge 3 which is fitted on the protruding rim provided on the outer peripheral side surface of the bottle mouth, and a thick ridge which fits on the protruding rim at a position where the knob 4 is provided. 5 are formed, and the whole of these is integrally formed of medium-hard synthetic resin or the like so as to form a thin groove 7 that can be cut off in the skirt portion located on both side edges of the knob piece 4. A simple bottle lid is described.

[0004]

The above prior art provides a simple plastic cap which can be opened by hand without requiring any special tool such as a bottle opener and which also has a function of preventing fraud. However, since this cap is sealed only at the two positions of the ridges 3 and the projections 5, there is still a problem in the sealing reliability, and first, the knob is pulled forward. There is a restriction on the opening operation that breaks the score and then pulls the knob side upward, and the score (weakened line) of the skirt is broken to open, so the opening force increases,
There is a problem that it is difficult to open.

[0005] Of course, if a slit (complete cutting line) is provided in place of the score 7, the opening operation becomes easy, but in this case, the engaging force between the convex piece 5 and the convex ring edge of the bottle is lost. It is clear that the sealing performance is insufficient. As described above, the cap using the combination of the projection for engagement with the bin, the seal of the bin, and the score of the skirt still has a problem in the easy-opening property, while the projection for engagement with the bin, There is still a problem in the sealing performance of the cap using the combination of the seal part and the slit of the skirt, and in the simple type stopper cap made of resin, satisfying both the easy opening property and the sealing property is as follows. It is not easy, if not difficult.

Although such a simple resin cap is expected to be applied to, for example, a chilled-filled milk container, even an infant, an elderly person, or even a sick person can easily perform an opening operation with a finger. In addition to being required to be sealed, it is required that the hermeticity be maintained even when the inside is left outdoors or indoors and the temperature rises.

[0007] Accordingly, it is an object of the present invention to make it easy to manufacture,
It is an object of the present invention to provide a simple resin cap which is easy to stopper and has an excellent combination of easy opening and sealing. It is another object of the present invention to improve the sealing performance of a resin cap using a combination of a projection for engagement with a bin, a seal portion of the bin, and a slit of a skirt.

[0008]

According to the present invention, there is provided a top plate and a skirt, wherein an inner surface of the skirt is provided with an engaging projection for engaging with a jaw of the container, and an inner surface of the top plate is provided with a container. In a resin cap formed with a seal portion with the mouth portion and an opening knob portion formed on the outer surface of the lower portion of the skirt portion, the skirt portions on both sides of the opening knob portion have protrusions for engagement from the lower portion of the skirt portion. At least a pair of slits extending toward the top plate portion beyond the portion, wherein the slits are 20 to 70 degrees from the radial direction, particularly preferably 30 to 60 degrees.
A resin cap characterized by being provided at an angle is provided. In the resin cap of the present invention, 1. The slit is formed so as to be inclined toward the engagement protrusion from a radial line passing through the inner end of the slit at or near one circumferential end of the engagement protrusion. The slit is preferably from 20 to 70 degrees, particularly preferably from 30 to 70 degrees from the radial line passing through the inner end of the slit toward the knob.
2. Being provided at an inclination of 60 degrees; 3. the seal portion is an inner ring sealed with the inner surface of the container mouth; 4. the engaging projections are provided in a form dispersed in a plurality through the missing portions; It is preferable that a reinforcing bead or a rib is formed at a lower portion of the skirt portion in the notch between the engaging protrusions.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The resin cap of the present invention comprises a top plate and a skirt, an inner surface of the skirt is provided with an engaging projection for engaging with a jaw of the container, and a container opening is provided on the inner surface of the top plate. A seal portion is formed with the skirt portion, and an opening knob is formed on an outer surface of a lower portion of the skirt portion. In the cap of the present invention, at least a pair of slits extending from the lower part of the skirt portion to the top plate portion beyond the engagement protrusion portion are formed in the skirt portions on both sides of the opening knob portion, and the slits are formed in a radial direction. 20 to 70 degrees, particularly preferably 30 degrees
It is characterized by being provided at an angle of up to 60 degrees.

[0010] That is, in this cap, since the skirt portions on both sides of the opening knob are provided with complete cutting lines,
The tearing force of the skirt is not required at the time of opening, and the complete cutting line extends from the lower part of the skirt beyond the engaging projection to the top plate, so that the opening knob is lifted up with a finger, and The engagement between the joint projection and the container jaw can be released with a relatively small force, which facilitates opening.

On the other hand, the loss of sealing in this type of cap is closely related to the radial expansion of the engaging projection. For example, for chilled milk, 5
Filling is generally performed at a temperature of about ℃, but if the container is left indoors or outdoors, the contents will heat up,
At the same time, the internal pressure also rises, the cap rises, and the engaging projections try to expand radially outward by contact with the container jaws, and this tendency to spread is due to the provision of slits on both sides of the opening knob. It is especially remarkable.

In the cap of the present invention, the slits are provided at an angle of 20 to 70 degrees, particularly preferably 30 to 60 degrees, from the radial direction. It overlaps with the inclined surface of both end edges of the skirt at a certain interval when viewed in the radial direction, and thereby abuts the skirt on the side of the knob portion in the radial direction. Loss of sex is prevented. In addition, since the slit is formed at least at one circumferential end of the engaging projection on the opening knob side or in the vicinity thereof and is inclined toward the engaging projection, the above effect is further improved. Moreover, this slope is
Although the skirt wall is prevented from spreading outward in the radial direction, the opening operation is extremely easy because the knob-side skirt wall moves along the inclined surface in the opening operation. When the slit is provided at an angle, the direction thereof is not particularly limited as long as the above-described overlapping occurs. For example, this inclination direction, when viewed in the radially outward direction, even if inclined to the opening knob side,
Or, conversely, it may be inclined to the opposite side to the opening knob, and when two or more slits are provided, a combination of both may be used.

It is also important that the inclination angle of the slit is in the above range with respect to maintaining the sealing property. If the angle is smaller than the above range, the contact area is too small and the effect of suppressing the spread in the radial direction is insufficient. On the other hand, if it is larger than the above range, the flexibility of the edge portion becomes too large, and the spread in the radial direction is also insufficient.

In the present invention, the sealing portion with the container opening provided on the inner surface of the top plate may be any member such as a packing, a liner or a gasket which engages with the top or inner and outer surfaces of the container opening. Preferably, the seal portion is an inner ring formed integrally with the top plate portion sealed with the inner surface of the container mouth. In this sealing structure, the sealing pressure is maintained by the cap from the inner surface side of the container mouth and the outer surface side of the container, and the sealing reliability is further ensured.

Further, it is preferable that the projections for engaging with the container jaws are provided in a form of being dispersed into a plurality of parts through the cutout portions in view of the balance between the sealing property and the easy opening property. That is, in the case where the engaging projection is provided over substantially the entire circumference of the cap, the opening force tends to be excessively large because the engaging projection has to climb over the container jaw to perform the opening. By disposing them in a form of being dispersed through a plurality of members, it is possible to maintain the sealing performance while weakening the opening force. The number of the engaging projections is 18 from the center of the opening knob.
It is appropriate to provide 2 to 4 pieces in the range of 0 degrees in terms of the balance between easy opening and sealing properties, and it is appropriate to provide them symmetrically with respect to a plane passing through the center. The circumferential length of the engaging protrusion may be constant or different for each protrusion, for example, from the opening knob to the opposite side, the circumferential length of the engaging protrusion may be different. Are provided so as to sequentially increase, so that a sufficient sealing property can be obtained while reducing the initial opening force.

In this case, the slit is formed so as to be inclined from the radial line passing through the inner end of the slit to the engagement projection at the outer peripheral end of one of the engagement projections or in the vicinity thereof. However, it is still preferable in view of the balance between the opening property and the easy opening property. In this case, on the inner surface of the skirt on the side of the knob for opening sectioned by the slit, there are an engaging projection and a gap between the engaging projections at both end edges. While helping to maintain hermeticity, the missing portion has the effect of facilitating lifting of the opening knob by finger.

Further, it is effective to form a reinforcing bead or rib at the lower part of the skirt portion in the notch between the engaging projections in terms of maintaining the hermeticity. That is, the engaging projection also has a reinforcing effect of increasing the strength of the skirt wall, but the lack of the engaging projection on the skirt wall of the missing portion has low strength and rigidity. On the contrary,
By providing the reinforcing beads or ribs in the notched portion, the strength and rigidity of the skirt wall of the notched portion can be increased, and excessive deformation in the notched portion can be prevented. In addition, in the cap of the present invention, it has already been pointed out that the circumferential both end edges of one skirt portion abut against the inclined surfaces of the both end edges of the other skirt portion, so that the radial outward spread is suppressed. As described above, the reinforcing beads or ribs provided in the missing portions also increase the strength of the inclined surface and effectively act to suppress the spread of the skirt wall.

The resin cap of the present invention is obtained by molding a cap precursor having the same structure as that described above except that no slit is formed by injection molding or compression molding of the resin, and then forming the cap precursor in a separate step. It is manufactured by forming a slit by cutting. In this cap, since there is no weakening line or score, the structure of the mold to be used is simple, and the molding operation and the die removing operation can be performed very quickly. Also, although two steps are required, it is advantageous that cutting can be performed very quickly. Also, at the time of tapping, there is no need to pay any attention or adjustment to avoid damaging the line of weakness or score, and there is an advantage that the tapping operation can be performed quickly and efficiently.

The resin used for molding is preferably a resin excellent in flexibility, elasticity and cushioning property in terms of sealing property and easy opening property, and olefin resin, for example, low-, medium- or high-density resin. Polyethylene, linear low-density polyethylene, ethylene-propylene copolymer, polybutene-1,
Ethylene-butene-1 copolymer, propylene-butene-
1 copolymer, ethylene-propylene-butene-1 copolymer, ethylene-vinyl acetate copolymer, ion-crosslinked olefin copolymer (ionomer), ethylene-acrylate copolymer, isotactic polypropylene, syndiotactic Tick polypropylene or the like is suitable.

In the present invention, the slits provided on both sides of the opening knob are generally 30 to 70 degrees, particularly 4 °, with respect to a line passing through the center of the opening knob and the center of the top plate.
Providing at an angle of 0 to 60 degrees may be advantageous in terms of the opening property and the sealing property. The slits may be provided in pairs, or two or more slits may be provided to facilitate opening. The second pair of slits is preferably provided at an angle larger than that of the first pair of slits, generally 80 to 120 degrees, particularly 90 to 110 degrees.

The opening knob is preferably provided so that the opening angle from the center of the top plate is generally 20 to 100 degrees, particularly 40 to 80 degrees, from the viewpoint of opening and sealing. .

Further, the engaging projection is provided so that the opening angle from the center of the top plate portion is generally 10 to 180 degrees, particularly 15 to 60 degrees, from the viewpoint of the opening property and the sealing property. . On the other hand, it is good in view of the opening property and the sealing property that the notched portion is provided so that the opening angle from the center of the top plate portion is generally 5 to 80 degrees, particularly 15 to 60 degrees.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the accompanying drawings. Partial cross-sectional side view (FIG. 1), bottom view (FIG. 2), enlarged view of a slit portion (FIG. 3), and cross-sectional view showing a state where the cap is attached to a container mouth showing an embodiment of the cap of the present invention. In FIG. 4, the cap of the present invention generally includes a cap 1 having a top plate 2 and a skirt 3 hanging from the outer periphery thereof.

On the inner peripheral surface of the skirt portion 3, an engaging projection 6 for engaging with the jaw portion 5 on the outer peripheral side of the container mouth 4 is formed. An inner ring 7 that engages with the inner peripheral side is formed, and sealing is performed on the inner peripheral side of the container opening 4. In this specific example, the sealing ridges 21, 2
2 is provided so as to be sealed with the container mouth portion 4, so that the sealing is further ensured.

An opening knob 9 is provided on the outer peripheral side of the lower part 8 of the skirt, and on both sides thereof, at least one pair of at least one pair extending from the lower part 8 of the skirt beyond the engaging projection 6 toward the top plate 2. Slits 10 and 10 are formed. The slits 10, 10 have a constant angle (θ) from the radial line a passing through the inner end of the slit toward the knob, ie, 20 degrees.
It is provided at an inclination of from 70 to 70 degrees, particularly preferably from 30 to 60 degrees.

In the cap of this specific example, a second pair of slits 11, 11 are also formed on the outside at a fixed interval from the slits 10, 10, and the inclination of the slits 11, 11 Same as 10 and 10.

Please refer to the enlarged view of the slit 10 (11) (FIG. 3). The skirt edge 31 on the opening knob side and the other skirt edge 32 are provided via an inclined surface 33 so as to overlap by a distance d when viewed in the radial direction. It is clear that the spread in the radial direction X is suppressed.

In the cap of this specific example, the engaging projections 6 are provided in a form of being dispersed into a plurality through the cutouts 12. That is, in this example, three engaging projections 6 are provided in the range of 180 degrees from the center of the opening knob, namely, 61, 62, and 63, and are provided around the periphery of the engaging projections 61, 62, and 63. The length is provided such that the circumferential length of the engaging projection gradually increases from the opening knob 9 toward the opposite side.

The first slits 10, 10 are formed at the outer peripheral ends of the engaging projections 61, 61 closest to the opening knob 9, or in the vicinity thereof. The engaging projections 61 are provided on the jaw 5 of the container mouth.
, And the hermetic seal is maintained. Further, at the time of opening, by pushing up the knob 9, the engagement between the engaging projections 61, 61 and the jaw 5 of the container opening is released, and the opening operation proceeds.

In the cap of this specific example, an inner peripheral side reinforcing bead or rib 13 and an outer peripheral side reinforcing bead or rib 14 are formed in the notch 12 between the engaging projections at the lower part of the skirt. The skirt wall of the missing portion 12 is reinforced. In the skirt portion on the side of the knob 9 for opening, no reinforcing beads or ribs 13 and 14 are provided, and the knob 9 for opening functions instead. On the outer periphery of the skirt portion 3, a long reinforcing rib 1 extending in the vertical direction is provided.
5 and short reinforcing ribs 16 are provided alternately to facilitate the gripping of the cap simultaneously with the reinforcement.

In the specific examples shown in FIGS. 1 to 4,
Although the two sets of slits 10 and 11 are provided at an angle θ to the opening knob side with respect to the radial line a,
In the specific example shown in FIG. 6, two sets of slits 10,
Of the 11, the slit 10 close to the opening knob is provided at an angle θ to the opposite side of the opening knob with respect to the radial line a.

[0032]

EXPERIMENTAL EXAMPLE 1 A cap having the form shown in FIGS. 1 to 5 was formed from low-density polyethylene by injection molding. The main dimensions of the formed cap are as follows. Minimum inner diameter d1 of skirt 3 ... 39.6 mm Lower inner diameter d2 of skirt 3 ... 40.0 mm Minimum inner diameter d3 of engagement projection 6 38.0 mm Minimum inner diameter d4 of reinforcing bead 13 ... 39.4 mm Maximum outer diameter d5 of reinforcing bead 14 ... 42.6 mm Lower end inner diameter d6 of inner ring 7 ... 26.4mm Upper end inner diameter d7 of inner ring 7 ... 26.0mm Maximum outer diameter d8 of inner ring 7 ... 28. 5 mm Upper outer diameter d9 of the inner ring 7 27.7 mm Lower outer diameter d10 of the skirt 3 41.8 mm Upper outer diameter d11 of the skirt 3・ ・ ・ ・ ・ ・ 41.4mm Cap height h1 ・ ・ ・ ・ ・ ・··· 10.5 mm Height h2 from the opening end of the reinforcing rib 15 ····· 7.0 mm Height h3 from the opening end of the reinforcing rib 16 ··· 3.5 mm Distance h4 between the center of the joint projection and the lower surface of the top plate 5.5 mm Distance h5 between the center of the inner ring 7 and the lower surface of the top plate 2.0 mm Distance h6 between lower end of inner ring 7 and lower surface of top plate 4.0 mm Thickness of top plate t1 1.6 mm In the bottom view (FIG. 2), a line connecting the innermost end of the slit to the outermost end and a line connecting the innermost end of the slit to the center of the cap are shown. The angle formed is 30 degrees (inclination angle). In the bottom view (FIG. 2), the circumferential angle between the center of the opening knob and the inner ends of the slits 10, 10 and the slits 11, 11 is 50 degrees for the slits 10, 10, and the slits 11, 11 are 100 degrees. The main dimensions of the milk bottle to which the above cap is attached are as follows. Inner diameter d12 of opening: 28.0 mm Outer diameter of opening d13: 40.0 mm The total capacity of the milk bottle is 213. 5 ml. 200 ml of milk cooled to 5 ° C. was poured into the milk bottle, and after the cap was capped, the milk bottle was placed in a temperature space maintained at 5 ° C., in a temperature space maintained at room temperature, and at 35 ° C. Were placed sideways in the temperature space held at, and allowed to stand for 24 hours to confirm the presence or absence of milk leakage and to conduct an experiment on the opening force at 5 ° C. The results were as shown in Table 1 below.

[Embodiment 2] In the bottom view (FIG. 2), the angle between the line connecting the innermost end and the outermost end of the slit and the line connecting the innermost end of the slit and the center of the cap is 60 degrees. Except for (inclination angle), the same cap as that of Example 1 was formed, and an experiment similar to that of Example 1 was performed. The results were as shown in Table 1 below.

Comparative Example 1 For comparison, a slit 10
An experiment similar to that of Example 1 was performed by forming the same cap as that of Example 1 except that a thin portion was used instead of 10 and the slits 11 and 11. The results were as shown in Table 1 below.

Comparative Example 2 For comparison, the same cap as that of Example 1 was formed except that the line connecting the innermost end and the outermost end of the slit was directed toward the center of the cap. Then, the same experiment as in Example 1 was performed. The results were as shown in Table 1 below.

[0036]

[Table 1] Form of slit for engagement Temperature (testing time: 24H) Opening force kg · f Projection 5 ° C Room temperature 35 ° C Example 16 Inclination angle 30 degrees ○ ○ ○ 1.7 Example 2 6 Inclination angle 60 Degree ○ ○ ○ 1.7 Comparative Example 16 Thin part ○ ○ ○ 2.8 Comparative Example 26 Inclination angle 0 ° ○ △ × 1.8 ○: No exudation or leakage was observed at all △: Milk bottle ×: Wetting (exudation) was observed at the upper end surface of the opening. ×: Leaking to the outside of the cap was clearly observed. The value of the opening force was an average value of 10 caps.

[0037]

According to the present invention, the top plate portion and the skirt portion are provided, the skirt portion inner surface is provided with an engaging projection for engaging with the jaw portion of the container, and the top plate portion inner surface is provided with the container opening. In a resin cap in which a seal portion is formed and an opening knob portion is formed on an outer surface of a lower portion of the skirt portion, the top plate is formed on the skirt portions on both sides of the opening knob portion from the lower portion of the skirt portion to beyond the engaging projection. Since at least a pair of slits extending toward the portion are formed, a tearing force is not required at the time of opening, and the opening knob is easily lifted with a small force. In addition, the slit is 20 to 70 degrees from the radial direction,
Particularly preferably, by being provided at an angle of 30 to 60 degrees, the circumferential end edges of the opening knob side skirt portion are spaced apart from the inclined surfaces of the other end edges of the other skirt portions by a constant distance in the radial direction. , So that the radial expansion is suppressed, and as a result, the loss of sealing due to the above-mentioned temperature rise and pressure rise is prevented. Although the inclined surface prevents the skirt wall from spreading outward in the radial direction, the opening operation is extremely easy because the knob-side skirt wall moves along the inclined surface in the opening operation. Furthermore, this cap has the advantage that it is easy to manufacture and the tapping operation is easy.

[Brief description of the drawings]

FIG. 1 is a partially sectional side view showing one embodiment of a cap of the present invention.

FIG. 2 is a bottom view of the cap of FIG. 1;

FIG. 3 is an enlarged view of a slit portion of the cap of FIG.

FIG. 4 is a cross-sectional view showing a state where the cap of FIG. 1 is attached to a container mouth.

FIG. 5 is an explanatory diagram for explaining various dimensions of the cap according to the embodiment.

FIG. 6 is a bottom view of a cap according to another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cap 2 Top plate part 3 Skirt part 4 Container mouth part 5 Jaw part 6 Engagement protrusion part 7 Inner ring 8 Lower part of skirt part 9 Opening knob 10 Slit 11 Slit 12 Missing part 13 Reinforcement bead or rib 14 Reinforcement bead or Rib 15 Reinforcement rib 16 Reinforcement rib 21 Sealing ridge 22 Sealing ridge 31 Skirt edge 32 Skirt edge 33 Slope 61 Engagement projection 62 Engagement projection 63 Engagement projection

Claims (6)

[Claims] A skirt portion provided on an inner surface of the skirt portion with an engaging projection for engaging with a jaw portion of the container, and a seal portion with a container mouth portion formed on an inner surface of the top plate portion; In a resin cap in which an opening knob is formed on the outer surface of the lower portion of the skirt, the skirts on both sides of the opening knob extend from the lower portion of the skirt to the top plate beyond the engagement protrusion. At least one pair of slits are formed, and the slits are provided at an angle of 20 to 70 degrees from the radial direction. 2. The slit is formed so as to be inclined from a radial line passing through the inner end of the slit to the engagement protrusion side at or near one circumferential end of the engagement protrusion. The resin cap according to claim 1, wherein: 3. The resin cap according to claim 2, wherein the slit is provided at an angle of 20 to 70 degrees from a radial line passing through the inner end of the slit toward the knob. 4. The resin cap according to claim 1, wherein the seal portion is an inner ring sealed with the inner surface of the container mouth. 5. The resin cap according to claim 1, wherein the engaging projections are provided in a plurality of forms via a cutout. 6. The resin cap according to claim 5, wherein a reinforcing bead or a rib is formed at a lower portion of the skirt portion in the notch between the engaging projections.