JP2015227179A - Bottle cap - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively prevent falling of a packing for sealing from the inside of a cap in a bottle cap having the packing press-fitted into a top wall of the cap.SOLUTION: A bottle cap includes: a topped cylindrical cap body 2; and a packing 10 that is disposed in the vicinity of a rear surface 4a of a top wall 4 in the cap body 2 and seals a mouth cylindrical part close to a bottle. A convex-shaped engaging projection 7 is formed on an inner peripheral surface 5 of the cap body 2. A packing holding region 8 for holding the packing 10 is disposed on the rear surface 4a of the top wall 4. A height dimension d of at least a peripheral edge part in the packing holding region 8 is made larger than a thickness dimension t of the packing 10 and does not exceed two times a thickness dimension t of the packing 10.

Description

  The present invention relates to a synthetic resin bottle cap that is attached to a mouth tube portion of a bottle, and more particularly to a bottle cap that prevents a sealing packing from falling off from the cap when the cap is opened.

  In the bottle cap that is screwed into the mouth tube that stands up from the upper end of the body of the bottle, the content liquid not only prevents leakage of the content liquid, but also blocks the inflow of oxygen and other germs and changes the flavor of the content liquid. For this purpose, it is effective to interpose a packing having excellent sealing properties between the mouth tube portion and the top wall of the bottle cap.

  In the invention described in Patent Document 1, a locking projection for locking the packing is provided on the peripheral wall near the top wall of the cap and at a position corresponding to the thickness of the packing to be mounted, and the packing is press-fitted into the cap and locked. A part of the periphery of the packing is locked by the locking protrusions over the protrusions.

Japanese Patent Laid-Open No. 9-2501

  However, in the invention described in Patent Document 1, for example, as shown in FIG. 5, the height dimension d between the top wall 104 of the cap 101 and the locking projection and the thickness dimension t of the packing are substantially the same dimension. Therefore, even when the peripheral edge 111 of the packing 110 press-fitted into the cap 101 by using the jig 120 cannot completely get over the locking projection 107, or even if it gets over as shown in FIG. In some cases, the peripheral edge 111 of the packing 110 is bent and deformed toward the locking protrusion 107 and is locked in a state where it floats from the back surface of the top wall 104 of the cap 101. When the cap is opened, the packing falls out of the cap. There was a problem that it remained in the mouthpiece.

  Conventionally, packing with PE foam PP sheet or PE foam PE sheet is often used as packing, but such packing is used for bottles whose contents need to be sterilized for a long time in a high temperature environment. In such a case, the packing may be deformed and the periphery of the packing may come off from the locking projection, and the locked state will become extremely unstable, so the packing may fall out of the cap when opening or setting. There was a problem that it was easy.

  The present invention enables the bottle cap in which the sealing packing is press-fitted into the top wall of the cap body to effectively prevent the packing from falling off from the cap in order to eliminate the above-described problems in the prior art. The challenge is to create a bottle cap.

Of the means for solving the above problems, the main configuration of the present invention is as follows.
A bottle cap comprising a cap body with a cylindrical shape and a packing that is provided in the vicinity of the back surface of the top wall in the cap body and seals the bottle-side tube portion,
A convex locking projection is formed on the inner peripheral surface of the cap body, and a packing holding region for holding the packing is provided on the back surface of the top wall.
The height dimension of at least the peripheral portion of the packing holding region is set to be larger than the thickness dimension of the packing and not more than twice the thickness dimension of the packing.

  In the main configuration of the present invention, when the packing is press-fitted into the packing holding region using a stoppering jig, it is eliminated that the peripheral edge of the packing is bent and deformed toward the locking projection. It is possible to push in sufficiently.

  According to another aspect of the present invention, in the configuration according to claim 1, the height dimension of the packing holding area is a dimension from a skirt portion that is a boundary between the locking projection and the packing holding area to a back surface of the top wall. It is said that.

  In the above-described configuration, the entire space between the locking projection and the back surface of the top wall is used as the packing holding region, so that the packing can be reliably pressed into the packing holding region.

  According to another aspect of the present invention, in the configuration according to claim 1, an annular groove-shaped thin portion is provided around the peripheral portion of the top wall, and the height dimension of the packing holding region is determined from the bottom surface of the thin portion. It is said that it is the dimension to the skirt part which is a boundary of a latching protrusion and a packing holding | maintenance area | region.

  In the above-described configuration, at least a part of the space corresponding to the periphery of the packing is used as the packing holding region, so that it is possible to reliably press-fit the packing into the packing holding region.

  According to another configuration of the present invention, in any of the above-described configurations, the packing is formed of a material that is more flexible than PE foamed PP sheet pasting or PE foamed PE sheet pasting.

  In the above configuration, even when a bottle cap is used for a bottle that sterilizes the contents for a long time in a high temperature environment, deformation of the packing can be suppressed.

  Another configuration of the present invention is that in the above configuration, the packing is formed of butyl rubber.

Since the present invention has the above-described configuration, the following effects can be obtained.
In the present invention, when the packing is press-fitted into the packing holding area, the packing can be sufficiently pushed into the back surface of the top wall in the packing holding area, so the bottle cap is attached to the mouth tube portion of the bottle. In this state, the packing completely adheres to the back surface of the top wall of the cap body, and it is possible to reliably prevent the packing from falling out of the cap body when the bottle cap is opened.

  Moreover, even if the bottle needs to be sterilized for a long time in a high temperature environment by forming the packing with PE foamed PP sheet or PE foamed PE sheet. There is no risk of deformation, and the holding of the packing by the locking projection becomes stable, so that the packing can be prevented from falling out of the cap body when opening or setting.

It is 1st Example of the bottle cap of this invention, and is a half section which shows the state which press-fitted the bottle cap into the bottle. FIG. 3 is a half cross-sectional view showing a state immediately before press-fitting packing into the bottle cap of FIG. 1. It is a half sectional view showing the 2nd example of the bottle cap of the present invention. FIG. 3 is a half sectional view showing a state after packing is pressed into the bottle cap of FIG. 2. It is a half sectional view showing a state just before press-fitting packing into a bottle cap as a conventional example. It is a half sectional view showing a state after press-fitting packing into a bottle cap of a conventional example.

First, a first embodiment of the present invention will be described with reference to FIGS.
The bottle cap 1A according to the first embodiment of the present invention is a lid body that seals a cylindrical mouth tube portion 21 that is erected on the upper end of a body portion of a bottle 20 made of synthetic resin or glass, for example. The bottle cap 1A has a top cylindrical cap body 2 in which a disc-shaped top wall 4 is integrally formed at the upper end of a cylindrical peripheral wall 3, and a packing 10 provided on the back surface 4a of the top wall 4. Configured.

  The cap body 2 is an injection molded product made of synthetic resin, and a female screw portion 6 is engraved on the inner peripheral surface 5 of the peripheral wall 3. When the female screw portion 6 is screwed into the male screw portion 22 formed in the mouth tube portion 21 on the bottle 20 side, the mouth tube portion 21 of the bottle 20 is sealed with the bottle cap 1A.

  On the inner peripheral surface 5 of the cap body 2 and at the position on the back surface 4a side of the top wall 4, a locking projection 7 that protrudes in a convex cross section toward the central axis O is provided. A maximum protrusion 7a is provided at the center of the locking projection 7 in the height direction, and a skirt 7b is provided at the boundary between the maximum protrusion 7a and the inner peripheral surface 5 that descends to the top wall 4 side.

  The packing 10 is a disk-shaped member having a thickness dimension t in the range of 0.5 mm to 3.0 mm, and is preferably formed of a material superior in flexibility to pasting of PE foamed PP sheet or PE foamed PE sheet. In particular, the hardness is preferably 40 to 50 degrees, and the material is preferably butyl rubber capable of suppressing deformation of the packing 10. For this reason, in this embodiment, the packing 10 is formed of butyl rubber having a hardness of 40 to 50 degrees.

  In the bottle cap 1 </ b> A, a packing holding region 8 is provided between the back surface 4 a of the top wall 4 of the cap body 2 and the skirt portion 7 b, and the packing 10 is held in the packing holding region 8. The height dimension d of the packing holding area 8 is larger than the thickness dimension t of the packing 10, and as shown in FIG. 1, the packing holding area 8 holding the packing 10 has a play portion 9 having a dimension a (= dt). Is provided. The dimension a of the play portion 9 is set to be equal to or greater than the amount of bending deformation of the peripheral edge 11 of the packing 10.

  Further, the inner diameter of the packing holding region 8 is formed to be the same as or slightly smaller than the outer diameter of the packing 10, and the inner diameter of the maximum protrusion 7 a is formed to be slightly larger than the outer diameter of the packing 10.

  As shown in FIG. 2, press-fitting of the packing 10 into the cap body 2 can be performed by, for example, plugging with the packing 10 and the jig 30 inserted from the opening end side of the cap body 2. When the packing 10 is plugged with the jig 30, the peripheral edge 11 of the packing 10 gets over the maximum protrusion 7 a of the locking projection 7 toward the top wall 4, and the entire packing 10 is pushed into the packing holding region 8. At this time, like the conventional example shown in FIG. 6, the peripheral edge 11 of the packing 10 is bent and deformed toward the locking projection 7, but the height dimension d of the packing holding area 8 is equal to the thickness dimension t of the packing holding area 8. Since the size a of the play portion 9 is set to be greater than or equal to the amount of deformation of the peripheral edge 11, the peripheral edge 11 of the packing 10 over the maximum protrusion 7a can be sufficiently pushed into the packing holding region 8. Is possible. For this reason, especially the play part 9 of the packing holding | maintenance area | region 8 functions as a space which returns the bending deformation of the peripheral edge 11, and can return the peripheral edge 11 to the state without the deformation | transformation before a deformation | transformation.

  When the packing 10 is press-fitted into the packing holding region 8 with the peripheral edge 11 not bent, as shown in FIG. 1, when the bottle cap 1 </ b> A is attached to the mouth tube portion 21 of the bottle 20, the packing 10 Can be completely brought into close contact with the back surface 4 a of the top wall 4 of the cap body 2. For this reason, it is possible to reliably prevent the packing 10 from falling out of the cap body 2 when the bottle cap 1A is opened.

The state in which the packing 10 after press-fitting is in the packing holding region 8 depends on the height d of the entire packing holding region 8 including the play portion 9. Table 1 below shows the results of tests conducted on the state of the packing 10 in the packing holding region 8 after press-fitting using the height d of the packing holding region 8 as a parameter.
In addition, the test was obtained three times when the packing 10 having a thickness dimension t = 2 mm was used to perform the plugging once. In Table 1, the mark “◯” indicates that the packing 10 is completely within the packing holding region 8. Is indicated as “no insufficient insertion”, and a mark X indicates a state in which the peripheral edge 11 of the packing 10 does not completely get over the maximum protrusion 7a, or a state in which the peripheral edge of the packing is bent and deformed even if it gets over. “Insufficient insertion”.

  From Table 1, when the height dimension d of the packing holding region 8 is set to 2.00 mm which is the same as the thickness dimension t of the packing 10, “there is insufficient insertion” that the peripheral edge 11 of the packing 10 does not always get over the maximum protruding portion 7 a. It can be seen that the state of “under-insertion” tends to be eliminated by reaching the state and making the height dimension d of the packing holding region 8 larger than the thickness dimension t of the packing 10.

  It can also be seen that when the thickness dimension t of the packing 10 is 2.00 mm, the state of “insufficient insertion” does not occur by setting the height dimension d of the packing holding region 8 to 2.50 mm or more. Therefore, it can be seen that the height d of the packing holding region 8 is preferably 2.50 mm or more when the thickness t of the packing 10 is 2.00 mm. In this case, it can be said that the dimension a (= dt) of the play portion 9 is preferably 0.5 mm or more.

  Further, when the thickness dimension t of the packing 10 and the height dimension d of the packing holding area 8 are compared, the height dimension d of the packing holding area 8 is preferably larger than the thickness dimension t of the packing 10, more preferably. It can be seen that the height dimension d of the packing holding region 8 is 1.25 (= 2.50 / 2.00) times or more the thickness dimension t of the packing 10. However, if the dimension a of the play portion 9 becomes too large, the packing 10 may flutter in the packing holding region 8 or the overall height of the cap body 2 may become too large. It is considered that the height d of the region 8 is preferably 2.0 times or less the thickness dimension t of the packing 10.

Next, a second embodiment of the present invention will be described with reference to FIGS.
The same members as those in the first embodiment will be described with the same reference numerals.
The bottle cap 1B shown in the second embodiment is different from the bottle cap 1A shown in the first embodiment in that a thin portion 4b made of an annular groove is formed on the peripheral portion of the back surface 4a of the top wall 4. Other configurations are the same as those of the first embodiment. Therefore, different parts will be mainly described below.

  In the bottle cap 1B shown in the second embodiment, the packing holding region 8 is in the range from the bottom surface 4b1 of the thin portion 4b to the skirt portion 7b. The overall height d of the packing holding region 8 is the same as that in the first embodiment, but the height between the back surface 4a and the skirt 7b is smaller by the depth of the thin portion 4b.

  As shown by a broken line in FIG. 3, the packing 10 is press-fitted into the packing holding region 8 using a jig as in the case of the first embodiment. When the packing 10 is plugged with the jig 30, the peripheral edge 11 of the packing 10 gets over the locking projection 7, and the entire packing 10 is pushed into the packing holding region 8. At this time, the periphery 10 of the packing 10 is bent and deformed toward the locking projection 7 by the maximum protrusion 7a. However, since the thin portion 4b is formed on the periphery of the back surface 4a, the height d of the packing holding region 8 is determined. Is larger than the thickness dimension t of the packing 10, and the packing 10 over the maximum protrusion 7 a can be sufficiently pushed into the packing holding region 8. For this reason, the particularly thin portion 4b of the packing holding region 8 functions as a space for restoring the bending deformation of the peripheral edge 11, and as shown by the broken line in FIG. 4, the peripheral edge 11 is not bent before the deformation, or FIG. As shown by a solid line, the peripheral edge 11 can be bent and deformed to the side of the top wall 4 which is opposite to the conventional direction.

  Therefore, when the mouth tube portion 21 of the bottle 20 is sealed with the bottle cap 1A as described above, the packing 10 can be completely brought into close contact with the back surface 4a of the top wall 4 of the cap body 2, and the bottle cap 1A is opened. It is possible to prevent the packing 10 from falling out of the cap body 2 when plugged.

  Even if it is a bottle that requires sterilization of the contents for a long time in a high-temperature environment by forming the packing 10 with PE foamed PP sheet or PE foamed PE sheet, it is superior in flexibility to butyl rubber. There is no risk of deformation. Therefore, it is possible to stabilize the holding of the packing 10 by the locking projection 7, and it is possible to prevent the packing 10 from falling out of the cap body 2 when opening or setting.

As mentioned above, although the structure of this invention and its effect were demonstrated along the Example, embodiment of this invention is not limited to the said Example.
For example, as a preferred embodiment, the above description has been given by showing butyl rubber having a hardness of 40 to 50 degrees, which is superior in flexibility to PE foamed PP sheet pasting or PE foamed PE sheet pasting, but the material and hardness of the packing are not limited to this. Absent.

  INDUSTRIAL APPLICABILITY According to the present invention, application development in the field of bottle caps in which a packing is press-fitted into a cap body and the sealing performance between the bottle-side mouth tube portion is enhanced can be achieved in a wider area.

DESCRIPTION OF SYMBOLS 1: Bottle cap 2; Cap main body 3; Peripheral wall 4; Top wall 4a; Top wall surface 4b; Thin part 4b1; Thin part bottom face 5: Inner peripheral surface 6; Female screw part 7; Locking protrusion 7a; Skirt portion 8; packing holding region 10; packing 11; peripheral edge 20 of the packing; bottle 21; mouth tube portion 22; male screw portion 30;

Claims (5)

A cap body (2) having a cylindrical shape with a top and a back tube (4a) in the vicinity of the top wall (4) in the cap body (2) to seal the mouth tube (21) on the bottle (20) side. A bottle cap comprising a packing (10),
A packing holding region in which a convex locking projection (7) is formed on the inner peripheral surface (5) of the cap body (2) and the packing (10) is held on the back surface (4a) of the top wall (4). (8) is provided,
The height dimension (d) of at least the peripheral portion of the packing holding region (8) is made larger than the thickness dimension (t) of the packing (10) and not more than twice the thickness dimension (t) of the packing (10). Bottle cap characterized by that.   The height dimension (d) of the packing holding region (8) is changed from the skirt (7b) which is the boundary between the locking projection (7) and the packing holding region (8) to the back surface (4a) of the top wall (4). The bottle cap according to claim 1, which has a size up to).   An annular groove-shaped thin portion (4b) is provided around the peripheral edge of the top wall (4), and the height dimension (d) of the packing holding region (8) is set from the bottom surface (4b1) of the thin portion (4b). The bottle cap according to claim 1, wherein the bottle cap has a dimension up to a skirt (7b) which is a boundary between the locking projection (7) and the packing holding region (8).   The bottle cap as described in any one of Claims 1 thru | or 3 which formed packing (10) with the material which has a softness | flexibility rather than PE foaming PP sheet sticking or PE foaming PE sheet sticking. The bottle cap according to claim 4, wherein the packing (10) is made of butyl rubber.

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