JP3884649B2 - A neck ring part in a plastic resin container or a preform for blow molding the container - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention, the cap is a neck ring section preform and that is provided integrally for blow molding a synthetic resin container or the container is screwed, the bottom surface of the neck ring section, made of the synthetic resin The present invention relates to a neck ring portion as a holding surface for holding and holding a container or the preform without idling.
[0002]
[Prior art]
Since it is necessary to attach a cap to the mouth of synthetic resin containers such as beverage containers, aluminum caps and synthetic resin caps are used. However, due to PET recycling problems and safety issues, aluminum caps are used. Changes from caps to synthetic resin caps are in progress.
[0003]
However, an aluminum cap and a synthetic resin cap have slightly different capping methods. Hereinafter, a method for attaching a cap to the mouth of a synthetic resin container will be described with reference to FIGS.
[0004]
FIG. 3 is a partial sectional view showing a preform 20 used for blow molding a PET (polyethylene terephthalate) resin bottle container (hereinafter referred to as PET bottle). 4 (a) and 4 (b) are cross-sectional views of the main part showing a state in which the neck ring portion 21 provided integrally with the preform 20 is fixedly held to the neck support 30, and a cap for the preform 20. It is principal part sectional drawing which shows the neck ring part 21 after screwing.
[0005]
First, when capping an aluminum cap, an unthreaded cap is placed on the mouth 20a formed on the preform 20, and a bottom surface 21f of the neck ring 21 formed integrally with the preform 20 is provided in the capping device. While pressing directly against the neck support 30 (see Fig. 4 (a)), apply a top load of about 1764N (Newton) and crush it with a rotating roller around the aluminum cap (not shown) to cut the screw. In this case, since the rotational torque is not so much applied to the preform 20 side, no countermeasure is required to prevent the preform 20 from spinning freely.
[0006]
On the other hand, when a cap made of synthetic resin is capped, a rotation torque is applied to the preform 20 because the cap is formed by capping the mouth 20a formed in the preform 20 while rotating the cap formed in advance. End up. For this reason, as shown in FIG. 4A, the neck support 30 is provided with a claw 31 as a measure for preventing the preform 20 from spinning around at a portion in contact with the bottom surface 21f of the neck ring portion 21.
[0007]
[Problems to be solved by the invention]
However, when capping the plastic cap, if the preform 20 slips, the bottom surface of the neck ring portion 21 is scraped, and if pressed firmly so as not to slip, the outermost peripheral portion 21e of the neck ring portion 21 has Since scratches such as burrs 21b shown in FIG. 4B are generated and the appearance of the neck ring portion 21 is damaged, it is necessary to make corrections by post-processing, or to replace and adjust the claws 31 in a complicated manner. There was an inconvenience of not becoming.
[0008]
The problem to be solved by the present invention has been made in view of these facts, and when a cap is screwed to a synthetic resin container or a preform for blow molding the container, the synthetic resin container Alternatively, scratches are prevented from occurring at the outermost peripheral portion of the neck ring portion provided integrally with the preform.
[0009]
[Means for Solving the Problems]
In order to solve this problem, the neck ring portion of the synthetic resin container or preform for blow-molding the container according to the first invention is blow-molded with the synthetic resin container or the container to which the cap is screwed. neck a neck ring section preform and that is formed integrally to the bottom surface of the neck ring section, and the synthetic resin container or retaining surface for fixing and holding without idling the preform to in the ring portion, the bottom surface of the neck ring section, the retracted position inwardly with respect to the outermost peripheral portion of the neck ring section, a stepped surface formed by slightly thickened the neck ring section, the it is characterized in that the stepped surface and said holding surface.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the drawings. In the present embodiment, a case where a cap is attached to a PET bottle obtained by blow-molding a preform will be described, and the basic shape of the preform will be described with reference to FIGS. In this embodiment, the same parts as those in FIGS.
[0011]
1 (a) and 1 (b) are cross-sectional views showing a main part of a neck ring portion 11 of a PET bottle 10 according to an embodiment of the present invention, and a neck ring of a preform 20 before being blow-molded in the related art. FIG. 2 (a) and 2 (b) are cross-sectional views of the main part showing a state in which the neck ring portion 11 provided integrally with the PET bottle 10 is fixedly held on the neck support 30, and a cap for the PET bottle 10. It is principal part sectional drawing which shows the neck ring part 11 after screwing.
[0012]
In the present embodiment, the holding surface of the neck ring portion 11 is a step surface 12f of the step 12 having a diameter φo smaller than the maximum diameter φmax of the neck ring portion 11 as shown in FIG. Specifically, it has a shape having a thickness Δd that is recessed inward by Δx with respect to the outermost peripheral portion 11 e of the neck ring portion 11.
[0013]
In this case, even if the stepped surface 12f is scratched, such as a burr 12b, the stepped surface 12f does not spread beyond the outermost peripheral portion 11e of the neck ring portion 11 due to the amount of retraction Δx. That is, when a plastic cap is capped, a burr 12b is generated on the step surface 12f of the step 12 in order to apply a top load so that the PET bottle 10 does not slip, and the outermost peripheral portion 11e of the neck ring 11 has No scratches such as burrs occur.
[0014]
Therefore, according to the present embodiment, when the cap is screwed to the PET bottle 10, it is possible to prevent scratches such as burrs generated at the outermost peripheral portion 11 e of the neck ring portion 11 provided integrally with the PET bottle 10. Therefore, there is an advantage that post-processing performed on the neck ring 11 is not necessary.
[0015]
In addition, according to the present embodiment, the portion where the nail 31 provided on the neck support 30 bites is limited to the stepped surface 12f, so that the nail 31 bites deeper and further suppresses the idle rotation of the PET bottle 10. Generation of flaws on the surface 12f can be prevented.
[0016]
The above description is merely a preferred embodiment of the present invention, and various modifications can be made by those skilled in the art within the scope of the claims. For example, the shape of the synthetic resin container is not limited to a bottle as long as it is a container for screwing a cap, and the material is not limited to PET resin. Further, regarding the cap, a so-called screw cap by screwing may be a metal cap such as aluminum in addition to the synthetic resin cap.
[0017]
【The invention's effect】
Therefore, in the first invention, the neck ring part of the synthetic resin container or the preform for blow molding the container is such that the bottom surface of the neck ring part is inward with respect to the outermost peripheral part of the neck ring part. the retracted position, a stepped surface to have a thickness in the neck ring section, because I the stepped surface and the holding surface, even if scratched on the stepped surface, by the amount retraction of the stepped surface, burrs and neck Does not spread beyond the outermost periphery of the ring. In other words, in the present invention, even when a top load is applied so that the synthetic resin container or preform does not slip when capping the cap, scratches such as burrs are generated on the stepped surface , and the neck ring portion is damaged. No scratches such as burrs occur on the outer periphery.
[0018]
Therefore, according to the present invention, when the cap is screwed to the synthetic resin container or the preform for blow-molding the container, the outermost periphery of the neck ring portion provided integrally with the synthetic resin container or the preform Since scratches occurring in the portion can be prevented, post-processing performed on the neck ring portion is not necessary, and the number of times of replacing and adjusting the nails can be reduced.
[0019]
In addition, according to the present invention, the portion that holds the synthetic resin container or the preform for blow-molding the container is limited to the step surface. For example, when the step surface is held by a nail, the nail Bites deeper and further suppresses the occurrence of idle rotation of the synthetic resin container or preform, so that it is possible to prevent the occurrence of flaws on the step surface.
[Brief description of the drawings]
FIGS. 1A and 1B are cross-sectional views of main parts showing a neck ring part of a PET bottle according to an embodiment of the present invention, and main parts of a neck ring part of a conventional preform, respectively. It is.
FIGS. 2A and 2B are a cross-sectional view of a main part showing a state in which a neck ring portion integrally provided with the PET bottle of the embodiment is fixedly held on a neck support, and FIG. It is principal part sectional drawing which shows the neck ring part after screwing a cap.
FIG. 3 is a partial cross-sectional view showing a preform used for blow molding a PET bottle.
FIGS. 4A and 4B are cross-sectional views of main parts showing a state in which a conventional neck ring portion integrally provided with a PET bottle is fixedly held on a neck support, and a cap for the PET bottle. It is principal part sectional drawing which shows the conventional neck ring part after screwing.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 PET bottle 10a Mouth part 11 Neck ring part 11e The outermost peripheral part 12 of a neck ring part 12 Step 12f Step surface 30 Neck support 31 Claw

Claims (1)

Cap a neck ring section preform and that is provided integrally for blow molding a synthetic resin container or the container is screwed, the bottom surface of the neck ring section, the synthetic resin container or the flop In the neck ring part that serves as a holding surface to hold the reform without idling,
The bottom surface of the neck ring part is a stepped surface formed by giving a thickness to the neck ring part at a position retracted inward with respect to the outermost peripheral part of the neck ring part. A neck ring portion in a synthetic resin container or a preform for blow molding the container, characterized in that the container is a holding surface.

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