JP2019064727A - Plastic cap and production method thereof - Google Patents

Abstract

To provide a plastic cap applicable to hot filling process and like, which is a one-piece type during a forming process and is transformed to two-piece type cap in use.SOLUTION: A plastic cap integrally formed with a cap body 1 through a breakable weakened part lower than a seal part with an inner diameter attachable on an inside plug of a pouring nozzle is configured by forming; a top cover 20 on which a protruded part 27 and a top plate part on which the pouring nozzle is formed are formed; an inner plug 30 on which an annular side wall attached to an inner surface of the pouring nozzle and a sealing part to seal the annular side wall are formed, wherein the inner plug is the plastic cap, an engaging part 33 engageable to an engaging part 28a of the protruded part being formed in the annular side wall of the plug and an annular protrusion 35 extending in a circumferential direction being formed on one surface of an outer surface of the annular side wall of the plug and the inner surface of the pouring nozzle as well as annular fitting parts 14a-c fittable to the annular protrusion by clamping it from vertical directions being formed on the other surface on which no annular protrusions of the outer surface of the annular side wall of the plug and the inner surface of the pouring nozzle are formed.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a plastic cap comprising a cap body having a small-diameter injection port fixedly used at a container opening and an upper lid, and more particularly, a hot, which has both openability and sealability. The present invention relates to a plastic cap that can also be used for filling and a manufacturing method that can form the plastic cap with high productivity.

Conventionally, in the case of a plastic cap consisting of a cap body and an upper lid fixedly used at the container opening, when the contents are first taken out, it is formed in the opening planned portion of the cap body top plate in order to ensure sealing. It is practiced to form an opening for content pouring by pulling up the resulting pull ring and breaking the weakened portion.
In the case of a cap applied to a container filled with a viscous content, the content is poured out by pressing the container body, so that the diameter of the outlet can be easily adjusted to adjust the pouring amount Is preferably small diameter. However, it is difficult to form a pull ring at the opening scheduled portion with a cap having a small diameter injection port. Even if the pull ring can be formed, it is difficult to hold the pull ring with a finger because the diameter of the pull ring is small, and as described above, the opening can not be easily formed at the start of use.

  A cap without a pull ring is also known. For example, in Patent Document 1 below, a cap main body provided with a pouring cylinder on the top wall and a cap main body are connected via a hinge portion, using the hinge portion as a fulcrum The inner lid is provided with an openable and closable outer lid and an inner lid that is held in the outer lid and seals the opening of the pouring cylinder, the inner lid being inward of the wall and the wall And an inner ring which is fitted into the opening of the dispensing cylinder when the upper lid is closed, and the outer lid is provided with a top wall and a skirt wall continuous with the top wall. And a cylindrical wall provided on the inner surface of the top wall on the inner side of the skirt wall and having a diameter larger than the opening of the pouring cylinder, the cylindrical wall having the inner lid facing inward. A hinge cap having holding means for holding, wherein the inner ring is at least on the hinge side of the wall The inner lid is slidably held at least in the height direction inward of the cylinder wall, and is moved along with the outer lid by the opening and closing operation of the outer lid. A feature has been proposed.

JP, 2014-162499, A

The above-mentioned hinge cap can be opened by one action to take out the contents since it is not necessary to pull up the pull ring to use for opening formation, and the inner lid is formed separately from the cap body and the outer lid. After being assembled, the inner lid can be moved separately from the upper lid because it is an assembled two-piece cap, and the sealing performance is also excellent.
However, since it is a two-piece type cap, two steps are added, that is, a step of forming the inner lid and a step of assembling the inner lid to the outer lid, and a mold for forming the inner lid is also required. Compared with the molding of a one-piece type cap, it is not yet sufficiently satisfactory in terms of productivity and economy.

In order to solve such a problem, the inventors of the present invention have a one-piece type which is excellent in productivity at the time of molding, but a small diameter for pouring out which becomes a two-piece cap which is excellent in sealing property and openability at the time of use. A plastic cap capable of forming an opening was proposed (Japanese Patent Application No. 2017-129504).
The plastic cap is integrally formed with the cap body via the weakened portion which can be broken below the seal portion having an inner diameter which can be in close contact with the inner plug of the dispensing nozzle. Since it is formed and the edge on the cap body side of the broken weakened part is located inside the pouring nozzle, it does not impair the pouring property of the contents and the seal point, and it is sealing. Excellent.

However, even when the above cap is used, when the filling condition such as hot filling or hot water shower is high temperature, stress relaxation by heat occurs in the seal portion, and the sealing force is reduced, and the filling treatment is performed. The internal plug may be moved due to the rise and fall of the internal pressure of the front and rear containers and the impact of the drop, etc., and the seal of the seal may be impaired. Therefore, in caps used for such applications, higher sealing performance is required.
Therefore, the object of the present invention is to use a one-piece type which is excellent in productivity at the time of molding, and a two-piece cap which is excellent in sealing property and opening property at the time of use. It is providing the plastic cap which can form an opening.
Another object of the present invention is to provide a method of forming a plastic cap capable of forming a plastic cap capable of forming a small diameter pouring opening having excellent sealing property and opening property with high productivity.

  According to the present invention, there is provided a cap body having a top plate portion and a skirt portion and having a pouring nozzle formed on the top plate portion outer surface so as to surround the opening planned portion; The upper cover includes a top surface and an upper lid having a circumferential wall depending from the outer periphery of the top surface, and the upper lid is formed with a protrusion projecting downward from the inner surface of the top surface and having an engaging portion on the outer surface. The cap body is formed with an inner wall formed with an annular side wall having an outer diameter capable of coming into intimate contact with the inner surface of the dispensing nozzle and a closing portion closing the annular side wall. A plastic cap integrally formed on a cap body via a weakening portion which can be broken below a seal portion having an inner diameter capable of adhering to the inner plug of the outlet nozzle, the annular side wall of the inner plug being formed Engaged in engagement with the engagement portion of the projection An annular projection extending in the circumferential direction is formed on either the annular sidewall outer surface of the inner plug or the inner surface of the dispensing nozzle, and the annular sidewall outer surface or outer surface of the inner plug is formed. There is provided a plastic cap characterized in that an annular fitting portion is formed on the other surface of the inner surface of the nozzle where the annular projection is not formed, the annular projection being insertable from above and below. Ru.

In the plastic cap of the present invention,
1. The inner plug is integrally formed from the edge of the opening scheduled portion of the top plate through a frangible weakening portion.
2. In a state where the upper lid is engaged with the cap body, the breakable weakened portion is fractured, and the engaged portion of the inside plug disengaging from the cap body can go over the engaging portion of the projecting portion and engage with each other Between the outer surface of the annular side wall and the inner surface of the dispensing nozzle.
3. A second engagement portion is formed above the engagement portion at the projection of the upper lid, and the inner plug ascends with the opening of the upper lid, and the annular projection is removed from the annular fitting portion Engaging the engaged portion with the second engaging portion after
4. The annular fitting portion is an annular recess conforming to the shape of the annular protrusion;
5. The annular fitting portion is formed by a lower annular ridge and an upper annular ridge;
6. The closed portion of the inner plug is a bottom portion formed below the annular side wall, and the bottom portion is formed with a guide rod extending upward, and the guide rod can be stored in the center of the protrusion A recess is formed, and the outer diameter of the guide rod is smaller than the inner diameter of the recess of the protrusion;
7. The upper lid being hinged to the cap body;
Is preferred.

Further, according to the present invention, after the cap body and the upper lid are formed, the closed portion of the inner plug is pressed from below while the upper lid is engaged with the cap body, and the breakable weakened portion is broken. And an annular projection formed between the engaging portion of the projection and the engaged portion of the inner plug and engageable and formed between the outer surface of the inner wall of the inner plug or the inner surface of the dispensing nozzle A method of manufacturing a plastic cap is provided, characterized in that the mating portion is engaged.
In the manufacturing method of the present invention, it is preferable that the cap body and the upper lid are hingedly connected, and the upper lid is engaged with the cap body after the cap body and the upper lid are formed in an open state.

In the plastic cap of the present invention, the seal portion formed between the annular sidewall outer surface of the inner plug and the inner surface of the pouring nozzle is formed by the engagement of the annular projection and the annular fitting portion, whereby hot filling is performed. As in the above, even when stress relaxation occurs due to heat when filling high temperature contents, etc., a reduction in sealing power is effectively prevented, and the sealing performance is excellent.
Further, the annular fitting portion has an upper annular protrusion and a lower annular protrusion, and an annular recess corresponding to the shape of the annular protrusion is formed between them, so that the annular protrusion and the annular fitting portion are fitted. The combined force can be improved, and the load in the vertical direction on the seal part, that is, the upward load due to the water hammer during drop or the rise in the internal pressure during hot filling, or the downward load due to pressure reduction absorption of the internal pressure after hot fill Also in the case where it acts, it is effectively prevented that the engagement between the annular projection and the annular engagement portion is released.
Furthermore, when the upper lid is closed immediately after the first opening, the engaged portion of the inner plug passes over the second engaging portion of the projecting portion formed on the upper lid, so that in the second and subsequent closed and open plugs, Since there is no engagement between the annular protrusion and the annular fitting portion described above, the opening force can be reduced and the opening property is excellent.

The plastic cap of the present invention is excellent in productivity because the inside plug can be integrally formed with the cap body.
Moreover, since the small diameter pouring opening which can not form a pull ring can be formed, while being able to pour only for the part which pressed the container, it can squeeze back easily and can prevent dripping etc. effectively.
Furthermore, since the inside plug integrally formed with the cap body is integrally formed with the cap body via the weakened portion which can be broken below the seal portion with the dispensing nozzle, the broken portion is weakened The end edge of the cap body side is located inside the pouring nozzle, and has excellent sealing performance without impairing the pouring property of the contents and the sealing property.
Further, in the plastic cap of the present invention, the inner plug engaging portion of the protrusion of the upper lid and the engaged portion of the inner plug are formed to have a gap in the vertical direction, so the inner plug is movable with respect to the upper lid Have. Therefore, the opening force can be dispersed to follow the movement of the upper lid after being delayed, and the initial opening force of the upper lid is not increased. In addition, since the inside plug does not move together with the upper lid even when the upper lid is subjected to a drop impact, the sealing performance is effectively prevented from being impaired.
Furthermore, the inner plug integrally formed on the cap body via the weakened portion is engaged with the projection formed on the upper lid while the inner plug is separated from the cap main body by pressing the closed portion from below the cap main body. Since it is integrated with the upper lid, it is easy to assemble and is excellent in productivity and economy.

The hinge cap which is an example of the plastic cap of this invention WHEREIN: It is a top view in the state which the upper lid after shaping | molding opened. In the hinge cap shown in FIG. 1, it is a sectional side view in the state which closed the upper cover after shaping | molding. In the hinge cap shown in FIG. 2, it is a figure for demonstrating the process of pushing up an inner plug from the downward direction, and setting to an upper lid. It is a side sectional view of the left half which shows the state where the annular projection of the inside plug pushed up from the lower part was fitted to the annular fitting part formed in the nozzle for pouring. FIG. 5 is a side cross-sectional view of the left half for illustrating a process in which the upper lid is first closed after the upper lid is first pulled up from the state shown in FIG. 4. FIG. 5 is a side cross-sectional view of the left half for illustrating a process in which the upper lid is first closed after the upper lid is first pulled up from the state shown in FIG. 4. It is a side sectional view of the left half showing a state where the upper lid is closed again and engaged with the cap body. It is a side sectional view of the left half for explaining the state which began opening from the state of Drawing 7 in the second or subsequent times.

The plastic cap of the present invention will be described based on the attached drawings.
An example of the plastic cap of the present invention shown in FIGS. 1 and 2 is formed so as to be detachable from the cap main body 1, the upper lid 20 hinged to the cap main body 1, and the cap main body 1 It is a hinge cap which consists of the inside plug 30 integrated with the upper lid | cover 20, and these are integrally shape | molded.
The cap body 1 fitted and fixed to the container opening (not shown) comprises a top plate 2 and a skirt 3 depending from the periphery of the top plate 2, and the skirt 3 is provided with a groove 4 extending downward from above The outer cylindrical wall 4 is divided into an inner cylindrical wall 3a and an outer cylindrical wall 3b, and the outer cylindrical wall 4 is formed so as to clamp the inner cylindrical wall 3a. The lower end portion of the groove 4 penetrates a partial region corresponding to the hinge portion of the upper lid 20 described later in the circumferential direction with the slit 12 and the region in the circumferential direction other than the slit 12 is the inner cylindrical wall 3a and the outer cylinder The wall 3 b is connected via the connecting portion 13. The connection portion 13 is formed of a break connection portion which can be broken in the circumferential direction and a non-break connection portion which is relatively thicker than the break connection portion. Below the inner surface of the inner cylindrical wall 3a, there is formed an inward projecting annular convex portion 5 which is engaged with an engagement concave portion of the container port to be described later to fix the cap main body 1 to the container port. . The outer cylindrical wall 3b is formed with a breakable axial score 6 extending downward from above in the vicinity of the hinge portion, whereby the contents disappear and when discarding, the upper lid 20 is moved downward at the hinge portion It pulls it down and breaks the score 6, and then the broken connection part of the connection part 13 is broken in the circumferential direction but the non-broken connection part is not broken, so it is easy from the container opening while the upper lid 20 and the cap main body 1 are connected. It can be removed and has separate disposal.
Further, an annular projection 7 for engaging with the upper lid 20 and fixing the upper lid 20 is formed at an end portion on the outer surface side of the top plate portion 2, and a pouring direction inside of the annular projection 7 (opposite to the hinge portion) The pouring nozzle 8 is formed on the side). On the other hand, an inner ring 9 in close contact with the inner surface of the container opening is formed on the inner surface of the top plate 2.

The inner plug, generally indicated at 30, is a boundary between the pouring nozzle 8 and the inner surface of the top plate 2 so as to close an opening planned part defined by the boundary between the pouring nozzle 8 and the inner surface of the top plate 2 It is integrally formed with the cap main body 1 via a breakable score (weakening portion) 10 in a portion (end edge of the opening scheduled portion).
The inner plug 30 is formed with an annular side wall 31 extending downward from the frangible score 10 and a bottom portion 32 which is a closed portion formed to close the annular side wall 31. Further, as described above, the outer diameter of the annular side wall 31 has a size to be in close contact with the seal portion of the inner surface of the dispensing nozzle 8, and the annular side wall 31 of the inner plug is a part of the inner surface of the dispensing nozzle It has a length that closely adheres to the Further, in the specific example shown in the figure, the bottom portion 32 is sloped so that the diameter decreases toward the lower end, and the inner plug is detached from the cap main body (breaking the weakened portion 10). After the inner plug 30 is set in a sealed state on the inner surface of the nozzle 8, when the upper lid is closed again, fitting into the dispensing nozzle 8 is facilitated.
In the inside of the inside plug 30, an annular engaged portion 33 to be engaged with the inside plug engaging portion 28 formed on the upper lid described later protrudes inward above the annular side wall 31. A guide rod 34 which is formed and extends upward from the center of the bottom 32 is formed.

  In the plastic cap of the present invention, as described above, it is an important feature that the annular projection and the annular fitting portion are formed on the outer surface of the annular sidewall 31 of the inner plug or the inner surface of the dispensing nozzle. In the specific example, an outwardly projecting annular projection 35 is formed on the outer surface of the annular sidewall 31 of the inner plug, and the inward projecting upper annular ridge 14 a and the lower surface are formed on the inner surface of the dispensing nozzle 8. Although the annular fitting part 14 which consists of the annular recessed part 14c divided by the side annular protrusion 14b is formed, the nozzle for pouring out and the annular fitting part may be formed in the inside plug in an annular protrusion. Since the annular recess 14c is formed to conform to the shape of the annular projection 35 of the inner plug, the annular projection 35 fits tightly in the recess 14c, so the sealing performance is improved.

An upper lid 20 generally shown at 20 is integrally formed with the cap body 1 via a hinge 11 at a position opposite to the pouring direction of the upper end of the outer cylindrical wall 4 of the cap body 1.
The upper lid 20 is composed of a top surface 21 and a circumferential wall 22 depending from the outer peripheral edge of the top surface 21. The lower surface of the circumferential wall 22 engages with the above-mentioned annular protrusion 7 of the cap body 1 An annular ridge 23 is formed to engage the upper lid 20 with the cap body 1 in the state. Further, at a position opposite to the hinge 11 at the lower end of the outer surface of the circumferential wall 22, a knob 24 for lifting the upper cover 20 is formed.
Further, on the top surface 21, a circumferential projection 25 is formed at a position corresponding to the dispensing nozzle 8 of the cap main body, and a downward extending downwardly extending same diameter as the tip outer diameter of the tip of the dispensing nozzle 8 is substantially the same. . By positioning the tip end of the spout of the dispensing nozzle 8 in the circumferential projection 25, the upper lid 20 is effectively prevented from being displaced from the cap main body 1 when the cap receives an impact from the outside, etc. it can. Further, except for the portion where the circumferential projection 25 is formed, the arc-shaped projection 26 is formed downward from the inner surface of the top surface 21. The arcuate projection 26 can prevent the upper lid from being crushed by an impact from above the upper lid 20 in the closed state.

On the inner side of the circumferential projection 25 of the upper lid, a downwardly projecting protrusion 27 is formed for engaging and fixing the inner plug 30 detached from the cap body 1. On the outer peripheral surface of the projecting portion 27, the first inner plug engaging portion 28a protruding outward at the tip thereof and the second inner plug engaging portion above the first inner plug engaging portion 28a 28b is formed. These inner plug engaging portions 28 are formed to be vertically engageable with the engaged portions 33 of the inner plug 30 described above, and as described later, until the upper lid 20 is first opened, The engagement portion 33 of the plug is disposed at a position where it can be engaged with the first inner plug engaging portion 28a, and when the upper lid is first opened and then closed again, the inner plug is engaged. The portion 33 can be engaged with the second inner plug engaging portion 28b by moving over the second inner plug engaging portion 28b, and the annular projection 35 of the inner plug engages with the annular fitting portion 14 of the dispensing nozzle In the case of the second and subsequent closing and opening operations, the inside plug 30 can be easily pulled out from the pouring nozzle 8 and the openability is improved.
Further, until the upper lid 20 is first opened, the first inner plug engaging portion 28a and the engaged portion 33 are formed to have a gap of L1 in the axial direction as shown in FIG. As will be described later, since the guide rod 34 has a small diameter and a short length with respect to the size of the recess 29, even if the upper lid 20 is slightly pulled up to be opened and the protrusion 27 is slightly inclined, The position of 30 does not change, only the protrusion 27 ascends simultaneously with the upper lid 20 and the inside plug 30 does not move from the dispensing nozzle 8 and the upper lid 20 is further pulled up from there and the sealed state of the inside plug 30 Will be released. Therefore, in the initial stage of opening the upper lid 20 (specifically, when the engagement between the annular projection 7 of the cap body 1 and the annular ridge 23 of the upper lid 20 is to be removed), the inside plug 30 still moves Since it does not increase the initial opening power of the upper lid 20 because it is fitted to the dispensing nozzle 8, the opening property is not impaired. In addition, the sealing property of the cap is not released in the initial state of opening.

Further, the protrusion 27 is formed with a recess 29 extending from the tip of the protrusion 27 toward the base (the top surface 21 side), and the guide rod 34 of the plug 30 described above is inserted into the recess 29. As a result, it is possible to prevent inclination of the detached inner plug 30 and to prevent the inner plug 30 from falling after detachment due to the projection 27 falling inside when the upper lid is opened. Further, as shown in FIG. 4, the tip 34 a of the guide rod 34 is positioned axially above the first inner plug engaging portion 28 a of the projecting portion 27 in a state in which the inner plug is integrated with the upper lid. And is located slightly above the axial direction of the engaged portion 33 of the inner plug 30. Thus, when the plug 30 is set on the upper lid 20, the first engagement portion 28a of the projection 27 is engaged with the plug 30 after the tip 34a of the guide rod 34 is inserted below the recess 29. In order to get over the part 33, it is possible to stably set the disengaging inner plug 30 without tilting.
The recess 29 has an inner diameter larger than the outer diameter of the guide rod 34, and is formed deeper than the length of the guide rod 34. As a result, the inside plug 30 has a movable area with respect to the upper lid 20, and the sealing performance can also be improved without increasing the initial opening force of the upper lid as described above.

  In the plastic cap of the present invention, as shown in FIG. 1, the cap body 1 and the inside plug 30 are integrally formed in a state where the upper lid 20 is opened, and then, as shown in FIG. 1 and the annular projection 7 of the cap main body 1 and the annular ridge 23 of the upper lid 20 are engaged and fixed, as shown in FIG. 3, from the lower side of the cap main body 1 using the pressing jig 40. The bottom 32 of the plug 30 is pushed up. As a result, as shown in FIG. 4, the plug 30 is pushed into the dispensing nozzle 8 at the same time as the score 10 is broken, and the guide rod 34 of the plug 30 is inserted into the recess 29 of the projection 27. At the same time, the engaged portion 33 passes over the first inner plug engaging portion 28a of the projecting portion 27 of the upper lid 20 to be able to engage with each other, thereby sealing the discharge nozzle 8 of the cap main body 1 by sealing. It is possible to fix the inside plug 30 to the upper lid 20 while keeping the state.

5-7 is a figure for demonstrating the process in which an upper lid is closed (it moves to the direction of the arrow X in the figure) immediately after the initial opening which pulled up the upper lid initially from the state shown in FIG.
As shown in FIG. 5, the upper lid 20 that has been opened first is in a position where the engaged portion 33 of the inner plug 30 can be engaged with the first engaging portion 28 a of the projection 27 of the upper lid 20. The outer diameter of the guide bar 34 of the inner plug 30 is smaller than the inner diameter of the recess 29 of the projecting portion 27, and the inner plug 30 abuts on the tip of the dispensing nozzle 8 in a state of being inclined with respect to the projecting portion 27. As a result, the plug 30 can be easily fitted into the pouring nozzle 8.
When the upper lid 20 is further moved in the direction of the arrow X, as shown in FIG. 6, the inside plug 30 pushed by the tip of the dispensing nozzle 8 moves in the upper lid direction (arrow Y). Is passed over the second engagement portion 28b of the projection and is fixed at a position where it can be engaged with the second engagement portion 28b.

Further, when the upper lid 20 is moved in the direction of the arrow X and fixed to the cap body 1 to be in a closed state, as shown in FIG. 7, the second inner plug engaging portion 28 b of the projection 27 and the inner plug 30 are covered The engaging portions 33 engage with each other in the axial direction. At this time, since the inner plug engaging portion 28b and the engaged portion 33 are formed to have a gap by the axial distance L2, the initial opening of the upper lid 20 is performed also in the second and subsequent closing and opening operations. It is excellent in openability without increasing the power.
As is clear from FIG. 7, in the closed state after being opened once, the annular projections 35 of the inner plug 30 are located above the upper annular ridges 14 a of the dispensing nozzle 8 and these are There is no engagement. Therefore, as shown in FIG. 8, in the second and subsequent closing and opening operations, since the annular projection 35 of the inner plug does not need to go over the upper annular ridge 14b of the dispensing nozzle 8, the force required for closing and opening is It has been reduced.

The plastic cap of the present invention is not limited to the specific example shown in the above-mentioned figures, and various modifications are possible.
That is, in the plastic cap shown in the figure, the cap body and the upper lid are connected by a hinge, and the cap body and the upper lid and the inside plug are integrally formed, but the upper lid is formed separately from the cap body , And may be fixed to the cap body by screw engagement or the like. Even in this case, since the inside plug can be formed integrally with the cap body, it is easy to form as compared with the conventional cap, and it is excellent in productivity and economy.
Also, since the cap body shown in the figure is a cap of the type fitted and fixed to the container opening, a double structure having an outer cylindrical wall with a score formed on the outside of the skirt for separate disposal. Although it was a thing of course, it may be a cap main part by which a screw part was formed in a skirt part fixed by container opening and screw engagement.
Furthermore, since the plastic cap of the present invention can exhibit excellent formability and sealing performance even in a cap having a small diameter pouring opening which can not form a pull ring, the size of the pouring opening is particularly large. It is preferable to be in the range of 3 to 18 mm.

The axial length of the inner plug can be changed as appropriate depending on the shape of the bottom of the inner plug etc. Preferably, it has a length of 40 to 100% of the axial length of the dispensing nozzle It is desirable from the viewpoint of both the ease of fitting the stopper into the dispensing nozzle and the sealing property.
In addition, the length of the axial gap L1 between the engaged part of the inner plug and the first inner plug engaging part of the projecting part can not be generally specified depending on the diameter of the cap and the size of the pouring opening. Preferably, the length is 20 to 80% of the axial length of the inner plug.
Furthermore, the shape of the bottom of the inner plug is not limited to the specific example shown in the figure, but various modifications are possible, but from the viewpoint of the ease of fitting the inner plug to the dispensing nozzle, the shape of the bottom It is preferable that the shape is a truncated cone shape, a hemispherical shape or the like in which a slope is formed at the boundary between the annular side wall and the bottom.

  Further, as shown in the figure, in the case where the inside plug is formed integrally with the cap body, the breakable weakened portion which is the connection part between the inside plug and the cap body has an annular shape of the inside plug on the inner surface of the dispensing nozzle. The outer surface of the side wall may be formed below the seal portion having an inner diameter which can be closely attached. That is, in the specific example shown in the figure, the lower end of the dispensing nozzle coincides with the top plate portion, and the inner plug is integrally formed at the end edge of the planned opening portion of the cap body via the breakable weakened portion. However, the present invention is not limited to this aspect. For example, in the case where the lower end of the dispensing nozzle is located below the top plate, the inner plug may be integrally formed via the weakening portion that can be broken at the lower end of the dispensing nozzle Or when the inner surface of the dispensing nozzle is partially reduced in diameter and the diameter-reduced portion is the seal portion, the inner surface of the dispensing nozzle below this seal portion The inner plug may be integrally formed via the frangible weakening portion.

In the hinge cap, the plastic cap of the present invention can be integrally molded by injection molding or the like with the upper lid opened. Next, the upper lid is folded and fixed to the cap body, and then the plug portion is pushed upward from below with a pressing jig or the like, thereby tearing the breakable weakened portion formed at the boundary between the cap body and the plug upper end, It becomes possible to fix the inside plug to the upper lid.
The cap of the present invention can be molded by a conventionally known method such as injection molding or compression molding using a resin that has been used for molding a conventional plastic cap such as an olefin resin such as polyethylene and polypropylene.
Also, when the inside plug is formed separately from the cap body, it is not limited to this, for example, by forming the cap body with polypropylene excellent in heat resistance, and forming the inside plug with polyethylene, heat resistance, sealing performance and opening It is possible to form a plastic cap with excellent character.

  The present invention is preferably molded as a plastic cap having a small diameter pouring opening which is difficult to form a pull ring, and can be suitably used as a cap for hot filled contents and Since the adjustment of the amount of pouring is easy and liquid dripping by squeeze back can be prevented, it can be used conveniently as a cap for squeeze bottles.

  DESCRIPTION OF SYMBOLS 1 Cap main body, 2 top plate part, 3 skirt part, 3a inner side wall, 3b outer side cylinder wall, 4 groove, 5 annular convex part, 6 breakable score, 7 annular projection, 8 pouring nozzle, 9 inner ring, 10 Breakable score (weakening part), 11 hinge, 12 slit, 13 connection part, 14 annular fitting part, 20 upper lid, 21 top surface, 22 circumferential wall, 23 annular ridge, 24 pinching, 25 circumferential projection, 26 arc-shaped projections, 27 projections, 28 inner plug engaging portions, 29 recessed portions, 30 inner plugs, 31 annular side walls, 32 bottom portions, 33 engaged portions, 34 guide rods, 35 annular projections.

Claims (10)

A cap body which comprises a top plate portion and a skirt portion, and a pouring nozzle is formed on the top plate portion outer surface so as to surround an opening planned portion, a cap body fitted and fixed to a container port, a top surface and the top surface It consists of an upper lid which consists of a circumferential wall which hangs down from the outer periphery, and the upper lid is projected downward from the top inner surface, and a projection which has an engaging portion on the outer surface is formed. An annular side wall having an outer diameter capable of coming into close contact with the inner surface of the dispensing nozzle, and a plug having a closed portion for closing the annular side wall are formed, the inner plug being a central plug of the dispensing nozzle A plastic cap integrally formed on the cap body via a weakening portion which can be broken below a seal portion having an inner diameter which can be in close contact with the cap portion,
The annular sidewall of the inner plug is formed with an engaged portion engageable with the engaging portion of the projecting portion,
An annular projection extending in a circumferential direction is formed on either the annular sidewall outer surface of the inner plug or the inner surface of the dispensing nozzle, and the annular sidewall outer surface of the inner plug or the annular surface of the inner surface of the dispensing nozzle A plastic cap characterized in that an annular fitting portion is formed on the other surface on which the projection is not formed, in which the annular projection can be fitted in the vertical direction.   The plastic cap according to claim 1, wherein the inside plug is integrally formed from an edge of the opening scheduled portion of the top plate portion via a breakable weakened portion.   In a state where the upper lid is engaged with the cap body, the breakable weakened portion is fractured, and the engaged portion of the inside plug disengaging from the cap body can go over the engaging portion of the projecting portion and engage with each other The plastic cap according to claim 1 or 2, wherein the annular side wall outer surface is in close contact with the inner surface of the dispensing nozzle.   A second engagement portion is formed above the engagement portion at the projection of the upper lid, and the inner plug ascends with the opening of the upper lid, and the annular projection is removed from the annular fitting portion The plastic cap according to claim 3, wherein the engaged portion engages with the second engaging portion after being engaged.   The plastic cap according to any one of claims 1 to 4, wherein the annular fitting portion is an annular recess conforming to the shape of the annular protrusion.   The plastic cap according to any one of claims 1 to 4, wherein the annular fitting portion is formed by a lower annular ridge and an upper annular ridge.   The closed portion of the inner plug is a bottom portion formed below the annular side wall, and the bottom portion is formed with a guide rod extending upward, and the guide rod can be stored in the center of the protrusion The plastic cap according to any one of claims 1 to 6, wherein a recess is formed, and an outer diameter of the guide rod is smaller than an inner diameter of the recess of the protrusion.   The plastic cap according to any one of claims 1 to 7, wherein the upper lid is hinged to the cap body.   After molding the cap body and the upper lid, the closed portion of the inner plug is pressed from below while the upper lid is engaged with the cap body, and the breakable weakened portion is broken and the projecting portion The engagement portion and the engagement portion of the inner plug are engageable, and the annular fitting portion is engaged with an annular projection formed between the outer surface of the outer wall of the inner plug or the inner surface of the dispensing nozzle. The manufacturing method of the plastic cap in any one of the Claims 1-8 characterized by these.   The method for manufacturing a plastic cap according to claim 9, wherein the cap body and the upper lid are hingedly connected, and the upper lid is engaged with the cap body after molding with the cap body and the upper lid opened.