JP4373522B2 - Plastic cap - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a synthetic resin cap that is attached to a mouth portion of a bottle or the like. More specifically, the present invention relates to a synthetic resin cap that can release high-pressure air generated in an upper lid.
[0002]
[Prior art]
A conventional synthetic resin cap has a pour cylinder portion, an inner lid having an engagement recess on its outer peripheral side, and an engagement protrusion that is fitted to the inner lid and is formed on the inner wall lower portion of the side wall portion. And an upper lid. When the synthetic resin cap is attached to the container mouth, the container is first filled with contents. In particular, in the case of liquid food seasonings having a relatively low salinity such as soups and sauces, the contents are filled in the container while being heated to 70 ° to 90 ° for sterilization.
After filling the contents, a cap with the upper lid fitted to the inner lid is attached to the mouth of the container by plugging or the like. After the cap is attached to the mouth, the container is washed with hot water of about 60 to 70 degrees as necessary.
[0003]
After the filling process and during the cleaning process, the inner space of the upper lid is sealed by the upper lid and the inner lid, so that the air in the upper lid expands by heating and the upper lid is pushed up, and the upper lid and the inner lid are engaged. May come off and the top lid may float or the top lid may open. For this reason, warm water and dust enter the upper lid and are unsanitary, and the upper lid must be pressed and closed again, which is troublesome.
[0004]
In order to solve this problem, the following synthetic resin cap is used (see Japanese Utility Model Publication No. 8-2124).
An inner lid to be attached to the container mouth, having an extraction tube on the top surface of the top plate portion of the inner lid, and an extraction lid removing portion on the inner lid top plate portion inside the extraction tube And a double synthetic resin cap having a structure in which the upper cover is fitted to the inner lid, and has an annular projecting portion in close contact with the inner surface of the pouring tube on the lower surface of the top plate portion of the upper lid. The thickness of the central portion of the top plate portion relative to the annular projection portion position is set to about one half of the thickness of the upper top plate portion which is the peripheral portion of the top lid top plate portion rather than the annular projection portion position. Double synthetic resin cap for liquid.
[0005]
[Problems to be solved by the invention]
The synthetic resin cap is intended to absorb the pressure increase by thinning the top lid top plate portion and deforming this portion, but has the following problems.
(1) Since there is a limit to the amount of deformation of the top lid top plate, the effect of preventing pressure rise is insufficient. Therefore, the upper lid opens without fully absorbing the pressure increase.
[0006]
(2) Since the top lid top plate is thin and easily deformed, the score formed on the top wall of the inner lid is liable to be damaged when the cap is worn. In addition, since the top plate portion is deformed when the upper lid is opened and closed, the feeling becomes worse.
[0007]
In view of the above circumstances, an object of the present invention is to prevent the upper lid from opening due to an increase in pressure in the upper lid.
[0008]
[Means for Solving the Problems]
The present invention, the pouring cylinder to the upper surface of the upper wall is provided, along with providing the infusion exit tube switching Dankabe inwardly, the inner cover having an annular engaging portion on the outer peripheral side of the infusion out cylinder, intermediate A synthetic resin cap provided with an upper lid fitted with a lid and provided with an annular engagement portion that engages with the annular engagement portion on the inner surface of the side wall; the annular engagement portion and the annular engagement portion Has an annular seal surface that is in close contact with each other and has a curved cross-sectional shape, and at least one of the annular engagement portion and the annular locking portion is an annular contact surface that is continuous with the other annular seal surface, or abuts an annular sealing surface, an annular abutment surface continuous with said annular sealing surface, said annular abutment surface, characterized in that it comprises an air relief means contiguous to said annular sealing surface.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
When the pressure in the upper lid rises, for example, at the time of plugging, the upper lid receives an upward force and is displaced in the opening direction. Therefore, the annular engagement portion of the upper lid is formed by the annular sealing surface of the annular locking portion of the inner lid and It rises along the annular contact surface. In the middle of the rise, both seal surfaces are separated, and the annular seal surface of the annular engagement portion comes into contact with the annular contact surface of the annular locking portion. At this time, the air in the upper lid is released into the atmosphere via the air escape means on the annular contact surface.
[0010]
This air escape means is provided on the annular contact surface of the annular engagement portion and the annular engagement portion having the annular seal surface and the annular contact surface, or on both annular contact surfaces. An air relief groove continuous with the surface. Further, instead of the air escape groove, a vertical protrusion or a recess surrounded by two adjacent vertical protrusions can be used as the air release means.
[0011]
The annular engaging portion, for example, the engaging protrusion is formed on the upper lid, and the annular engaging portion, for example, the engaging concave shape is formed on the inner lid, but in the opposite manner, that is, the engaging concave portion is formed on the upper lid. In addition, an engagement protrusion may be provided on the inner lid.
[0012]
When the air in the upper lid is discharged into the atmosphere through the air escape groove, the annular engagement portion and the annular locking portion are still in the engaged state, and when the pressure in the upper lid decreases, the upper lid Falls by being pressed by atmospheric pressure. Therefore, the annular locking portion and the annular engagement portion return to the original engagement state.
[0013]
【Example】
A first embodiment of the present invention will be described with reference to FIGS.
The synthetic resin cap 1 includes an inner lid 2 attached to the container mouth portion, and an upper lid 20 fitted to the inner lid 2.
[0014]
The inner lid 2 is provided with an upper wall 4 that closes the upper end of the cylindrical portion 3. A pouring cylinder 5 is erected on the upper surface of the upper wall 4, and a cutting wall 7 surrounded by a score 6 is provided on the inside thereof. A pull ring 8 is provided at the tip of the cutting wall 7.
[0015]
A concentric annular locking portion, for example, an engagement recess 9 is provided on the outside of the dispensing tube 5. The engagement recess 9 is provided with an annular seal surface 9a and an annular contact surface 9b. The contact surface 9b is continuous with the lower end of the seal surface 9a.
[0016]
An annular protrusion 11 is provided on the inner surface of the cylindrical portion 3, and this protrusion 11 engages with an outer peripheral recess of a container mouth portion (not shown). The container mouth portion is sandwiched between the cylindrical portion 3 and the inner cylindrical portion 10.
[0017]
The upper lid 20 includes a top plate portion 21 and a side wall portion 22. Although the annular projections 21a and 21b are provided on the back surface of the top plate portion 21, the annular projections 21a and 21b abut against the distal end portion 5a of the dispensing cylinder 5 and perform a sealing action when the lid is closed.
[0018]
An annular engagement portion, for example, an engagement protrusion 25 is provided on the inner surface of the lower end portion of the side wall portion 22. The engagement surface of the engagement protrusion 25 has an arcuate cross section, and includes an annular seal surface 25a and an annular contact surface 25b. The seal surface 25a is in close contact with the annular seal surface 9a of the engaging recess 9 when the lid is closed.
The annular contact surface 25b is continuous with the lower end of the annular seal surface 25a and contacts the annular contact surface 9b of the engagement recess 9.
[0019]
The annular contact surface 25b is provided with air escape means. An air escape groove (air vent) is used as the air escape means 26. The length, direction, depth, number, shape, and the like of the air escape groove 26 are appropriately selected as necessary.
For example, as the groove 26, a plurality of grooves continuous to the lower end of the annular seal surface 25a are employed.
[0020]
Next, the operation of this embodiment will be described.
In the closed state, as shown in FIG. 2, the tip of the dispensing tube 5 and the annular protrusions 21 a and 21 b are in close contact to form an inner sealed chamber 28, and the engagement protrusion 25 of the side wall 22 The outer sealing chamber 29 is formed by closely contacting the annular sealing surface 25a and the annular sealing surface 9a of the engaging recess 9.
[0021]
When the temperature of the air A in the inner sealed chamber 28 rises, the pressure in the sealed chamber 28 increases, so that the top plate portion 21 of the upper lid 20 is pressed and deformed as shown in FIG. , 21b is separated from the dispensing cylinder 5, and a gap is generated between the two, 21a, 21b. Therefore, the air A flows into the outer sealed chamber 29 through the gap.
At this time, since both the annular sealing surfaces 9a and 25a maintain the sealed state, the pressure in the outer sealing chamber 29 gradually increases.
[0022]
Further, when the pressure in the inner sealed chamber 28 increases, the top plate portion 21 is further displaced upward as shown in FIG. 4, and the side wall portion 22 is also displaced upward. At this time, the engagement protrusion 25 of the side wall portion 22 rises while sliding on the annular seal surface 9 a and the annular contact surface 9 b of the engagement recess 9 of the inner lid 2.
[0023]
When the lower end of the annular seal surface 25a of the engagement protrusion 25 is separated from the annular seal surface 9a of the engagement recess 9, the annular contact surface 25b of the engagement protrusion contacts the annular seal surface 9a of the engagement recess. The engagement state of the both 9 and 25 is maintained in contact with each other, and the outer sealing chamber 29 communicates with the atmosphere through the air escape groove 26.
[0024]
Then, the air in the sealed chambers 28 and 29 is released from the air escape groove 26 into the atmosphere, so that the pressures in both the chambers 28 and 29 rapidly decrease. Therefore, the force which presses the upper lid 20 upward is weakened, and the rise of the side wall portion 22 is stopped, so that the upper lid 20 does not open.
[0025]
Thereafter, when the pressure in the chambers 28 and 29 is reduced to the atmospheric pressure or less with the temperature drop of the solution in the filling, the top plate portion 21 is pressed downward by the atmosphere, and as shown in FIG. Return to state.
[0026]
A second embodiment of the present invention will be described with reference to FIG. The difference between this embodiment and the first embodiment is that the annular contact surface 39b is made continuous with the upper end of the annular seal surface 39a of the engagement recess 39 of the inner lid 2, and the engagement protrusion 35 of the side wall portion 22 is An annular contact surface 35b is formed continuously at the upper end of the annular seal surface 35a, and an air escape groove 46 is formed in the annular contact surface 39b of the engagement recess 39 of the inner lid.
[0027]
In this embodiment, when the side wall portion 22 rises due to the displacement of the upper lid 20, the engagement protrusion 35 rises while sliding on the annular seal surface 39 a and the annular contact surface 39 b of the engagement recess 39.
When the lower end of the annular seal surface 35a is separated from the annular seal surface 39a, the annular sealing surface 39b contacts the annular contact surface 39b to maintain the engagement state therebetween, and the outer sealed chamber 29 is allowed to escape from the air. It communicates with the atmosphere via the groove 46.
[0028]
The embodiment of the present invention is not limited to the above. For example, instead of providing an engaging recess in the inner lid and providing an engaging protrusion on the side wall of the upper lid, the reverse, that is, engaging the inner lid. A protrusion may be provided, and an engaging recess may be provided in the side wall portion of the upper lid. The upper lid is preferably a so-called hinge lid that is connected to the middle lid via a hinge.
[0029]
【The invention's effect】
In the present invention, since the air escape means is provided on the annular contact surface as described above, when the pressure in the upper lid rises and the upper lid is deformed and the annular engagement portion is displaced, the air in the upper lid is air escape means. Is released into the atmosphere via Therefore, since the pressure in the upper lid is lowered, the lid is not opened, and when the pressure in the upper lid becomes lower than the atmospheric pressure as the temperature of the solution in the container falls, the upper lid returns to the original sealed state. .
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a first embodiment of the present invention.
FIG. 2 is an enlarged view of a main part of FIG.
3 is a cross-sectional view showing another state of FIG. 2 and showing a state in which the pressure in the upper lid has increased. FIG.
4 is a cross-sectional view showing still another state of FIG. 2 and showing a state in which the pressure in the upper lid is further increased. FIG.
FIG. 5 is an enlarged cross-sectional view showing an engagement state between an engagement protrusion and an engagement recess.
FIG. 6 is a cross-sectional view showing a second embodiment of the present invention and corresponds to FIG.
[Explanation of symbols]
2 Middle lid 9 Engaging recess 9a Annular seal surface 9b Annular abutment surface 20 Upper lid 25 Engagement projection 25a Annular seal surface 25b Annular abutment surface 26 Air escape groove 35 Engagement projection 35a Annular seal surface 35b Annular abutment surface 39 Joint recess 39a Annular seal surface 39b Annular contact surface 46 Air escape groove

Claims (6)

The pouring cylinder is provided on the upper surface of the upper wall, fitting provided with a infusion exit tube switching Dankabe inwardly, the inner cover having an annular engaging portion on the outer peripheral side of the infusion out cylinder, the intermediate lid And an upper lid provided with an annular engagement portion that engages with the annular locking portion on the inner surface of the side wall portion;
The annular engagement portion and the annular engagement portion have an annular seal surface that is in close contact with each other and has a curved cross-sectional shape, and at least one of the annular engagement portion and the annular engagement portion is the other annular seal. An annular contact surface that is continuous with the surface, or an annular contact surface that is continuous with the annular seal surface that contacts the annular seal surface, and the air release means that the annular contact surface is continuous with the annular seal surface A synthetic resin cap characterized by comprising: 2. The synthetic resin cap according to claim 1, wherein the air escape means is an air escape groove formed in one of the annular engagement portion and the annular locking portion. The synthetic resin cap according to claim 1, wherein the air escape means is an air escape groove formed in the annular engagement portion and the annular locking portion. 4. The synthetic resin cap according to claim 1, 2, or 3, wherein the air escape means is a plurality of air escape grooves formed in the vertical direction. The annular locking portion is an engagement recess formed in the inner lid,
The synthetic resin cap according to claim 1, 2, 3, or 4, wherein the annular engaging portion is an engaging protrusion formed on an inner surface of the side wall portion of the upper lid. The synthetic resin cap according to claim 1, 2, 3, 4, or 5, wherein the upper lid and the inner lid are connected via a hinge.

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