Screw caps and containers with screw caps
The screw cap with inclined flow path projections addresses the issues of deformation and resistance in existing designs, ensuring easy attachment and efficient water drainage with improved printability.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- NIPPON CLOSURES
- Filing Date
- 2024-11-28
- Publication Date
- 2026-06-09
AI Technical Summary
Existing screw caps with tamper-evident bands face issues such as increased sliding resistance and deformation of flow channel-forming projections, leading to inefficient water drainage and reduced printability due to circumferential compression during attachment, which can crush the projections and narrow the flow path.
The screw cap design features a tamper-evident band with locking projections and inclined flow path-forming projections that align with the cap's threaded direction, preventing circumferential compression and maintaining a wide flow path for efficient water drainage, while reducing sliding resistance and enhancing printability.
The design ensures easy attachment, efficient water drainage, and improved printability by suppressing projection deformation and maintaining a stable flow path, reducing resin usage and attachment resistance.
Smart Images
Figure 2026093699000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a screw cap having a cap body and a tamper-evident band connected to the lower part of the cap body, and particularly to a screw cap having a function of draining washing water.
Background Art
[0002] Conventionally, in a screw cap having a tamper-evident band for proving an opening history, by providing protrusions on the inner surface of the tamper-evident band, a flow path is secured between the inner surface of the tamper-evident band and the container jaw portion, and a screw cap having a function of draining washing water for discharging residual washing water by a shower washing process for removing the contents adhering to the container mouth portion is known. It is disclosed that printing such as manufacturing information on the outer peripheral surface of the tamper-evident band is prevented from bleeding due to the adhesion of washing water (see, for example, Patent Document 1).
[0003] This plastic cap 1 known from Patent Document 1 etc. (the names and reference numerals of the components in this paragraph follow the notations in Patent Document 1) has a TE band 7 connected by a plurality of breakable bridges to the lower end of a skirt wall 5 descending from the periphery of a top plate 3, and a slit 9 which is a minute gap is formed between the lower end of the skirt wall 5 and the upper end of the TE band 7. On the inner surface of the TE band 7, a locking protrusion 19 having a hook shape and located below a jaw portion 53 formed on the outer surface of a container mouth portion 50, and a protrusion 30 for forming a flow path are provided above the locking protrusion 19. Since the protrusion 30 for forming a flow path is provided so as to abut on the jaw portion 53, a gap X serving as a flow path for washing water is formed around the protrusion 30 for forming a flow path between the inner surface of the TE band 7 and the outer surface of the jaw portion 53. Thereby, when droplets Y of washing water are accumulated in the upper part of the jaw portion 53, by blowing air onto the droplets Y through the slit 9, the droplets Y pass through the gap X and are discharged without adhering to the outer surface of the TE band 7 from below the jaw portion 53. The plastic cap 1 has a water drainage function for the cleaning water, thereby preventing the cleaning water from flowing out of the slit 9 and preventing the smudging of printing, etc., caused by the cleaning water adhering to the outer surface of the TE band 7. [Prior art documents] [Patent Documents]
[0004] [Patent Document 1] Japanese Patent Publication No. 2022-153878 [Overview of the Initiative] [Problems that the invention aims to solve]
[0005] The plastic cap 1 (the names and reference numerals of the components in this paragraph follow the notation in Patent Document 1, etc.), which is known in Patent Document 1, etc., has flow channel forming projections 30 formed in a rib shape or block shape that extends in the axial direction, and is configured to be positioned in each of the portions between adjacent locking projections 19. Therefore, when the plastic cap 1 is attached to the container opening 50 by screwing it on, the channel-forming projection 30 comes into contact with the jaw portion 53 and is compressed radially while receiving force in the rotational direction, which could cause the channel-forming projection 30 to be crushed in the circumferential direction. Furthermore, the circumferential compression of the channel-forming projection 30 increased the sliding resistance between the channel-forming projection 30 and the jaw portion 53, potentially making it difficult to attach the plastic cap 1 to the container opening 50. Furthermore, the flow channel forming projection 30 is crushed in the circumferential direction, reducing its radial height and narrowing the void X. As a result, the droplet Y cannot pass through the void X, and the water drainage function is not fully realized. This can lead to cleaning water adhering to the outer surface of the TE band 7, potentially reducing the printability of the TE band 7. Furthermore, if the number of channel-forming protrusions 30 is increased to secure the void X, or if the diameter of the cap 1 is designed to be larger, there is a risk that the sliding resistance will increase further.
[0006] The present invention aims to solve these problems by providing a screw cap and a container with a screw cap that have a simple structure, do not narrow the flow path of cleaning water when attached to the container opening, are easy to attach to the container opening, and can improve the printability of the tamper-evident band. [Means for solving the problem]
[0007] The screw cap of the present invention is a screw cap having a cap body and a tamper-evident band connected to the lower part of the cap body, wherein the cap body has a cap top surface, a skirt wall hanging down from the outer peripheral edge of the cap top surface, and a cap-side threaded portion formed on the inner circumferential surface of the skirt wall, and the tamper-evident band has a cylindrical band body and a weakening portion connecting the upper end of the band body to the lower end of the skirt wall, wherein the inner circumferential surface of the band body is provided with a locking projection that can engage with the lower side of the container jaw, and a flow path forming projection that contacts the outer surface of the container jaw at a position above the locking projection to form a space that serves as a flow path for washing water between the container jaw and the inner circumferential surface of the skirt wall, and the flow path forming projection is formed to extend inclined in the same direction as the side on which the cap-side threaded portion is inclined with respect to the circumferential direction of the inner circumferential surface of the cap body, thereby solving the aforementioned problems. Furthermore, the screw-capped container of the present invention solves the aforementioned problems by having the above-mentioned screw cap attached. [Effects of the Invention]
[0008] According to the inventions of claims 1 and 7, the inner circumferential surface of the band body is provided with a locking projection that can engage with the lower side of the container jaw, and a channel-forming projection that abuts against the outer surface of the container jaw at a position above the locking projection, thereby forming a space that serves as a flow path for cleaning water between the container jaw and the inner circumferential surface of the skirt wall. The channel-forming projection is formed to extend in the same direction as the side on which the cap-side screw portion is inclined with respect to the circumferential direction of the inner circumferential surface of the cap body, thereby suppressing circumferential compression of the channel-forming projection due to the force it receives in the rotational direction when the screw cap is attached to the container opening by screwing it on. This suppresses crushing of the channel-forming projection, prevents narrowing of the space that serves as a flow path for cleaning water, allows for efficient discharge of the cleaning liquid, and improves the printability of the tamper-evident band. Furthermore, when the screw cap is attached to the container opening by screwing it on, the circumferential compression caused by the rotational force on the flow-forming projection is suppressed, thereby reducing the sliding resistance between the flow-forming projection and the container jaw, making it easier to attach the screw cap to the container opening. Furthermore, the cleaning water remaining at the top of the container jaw flows along the slope above the channel-forming protrusion, allowing for efficient drainage of the cleaning water.
[0009] According to the configuration described in claim 2, the channel-forming protrusions are arranged in multiple locations with spacing in the circumferential direction, and when viewed in the axial direction of the band body, the circumferential length of each channel-forming protrusion extends at an angle of 10° to 60°. This ensures that a sufficient length is secured to suppress the crushing of the channel-forming protrusions when the screw cap is attached to the container opening, and furthermore, it is possible to suppress an increase in the amount of resin required for screw cap molding.
[0010] According to the configuration described in claim 3, the locking protrusions are arranged in a plurality at intervals in the circumferential direction, and the flow path forming protrusions are formed to straddle the spacing between adjacent locking protrusions when viewed in the axial direction of the band body. As a result, the flow path of the cleaning water generated by the contact between the flow path forming protrusions and the container jaw is in close proximity to the circumferential gap portion of the locking protrusions. The cleaning water that has passed through the flow path generated by the contact is efficiently discharged through the circumferential gap portion of the locking protrusions, thereby improving the printability of the tamper-evident band.
[0011] According to the configuration described in claim 4, the channel-forming projection is formed so as to extend inclined at the same angle as the inclination angle of the screw portion on the cap side with respect to the circumferential direction of the inner surface of the band body, and each has the same circumferential length. As a result, when the screw cap is attached to the container opening by screwing, the position in which the channel-forming projection contacts the container jaw does not change, and fluctuations in the circumferential compressive force due to the force received by the channel-forming projection in the rotational direction are suppressed, thereby further reducing the sliding resistance between the channel-forming projection and the container jaw, making it easier to attach the screw cap to the container opening.
[0012] According to the configuration described in claim 5, the upper surface of the locking projection has an inclined surface that connects with the inner diameter gradually decreasing from top to bottom, and the flow path forming projection is formed to extend at an axial distance from the upper end of the inclined surface. As a result, when the screw cap is opened, the locking projection and the lower side of the container jaw can engage uniformly around the entire circumference, preventing the band body from slipping off.
[0013] According to the configuration described in claim 6, the channel-forming projection has a protruding height of 0.05 mm or more and 1.0 mm or less, and an axial width of 0.30 mm or more and 2.0 mm or less, which makes it easier to attach to the mouth of the container, suppresses the generation of resin fragments due to abrasion of the channel-forming projection caused by contact with the container jaw when the screw cap is attached, and allows for efficient discharge of cleaning water. [Brief explanation of the drawing]
[0014] [Figure 1] Partial cross-sectional view of a screw cap according to an embodiment of the present invention. [Figure 2] Enlarged view of the region surrounded by the circle indicated by the dashed line in FIG. 1. [Figure 3] Partial side cross-sectional view passing through the protrusion for forming a flow path when the screw cap according to an embodiment of the present invention is attached to the mouth portion of the container. [Figure 4] Partial side cross-sectional view passing through the space formed by the protrusion for forming a flow path when the screw cap according to an embodiment of the present invention is attached to the mouth portion of the container. [Figure 5] Perspective view of the tamper-evident band of the screw cap according to an embodiment of the present invention. [Figure 6] Top view of the tamper-evident band of the screw cap according to an embodiment of the present invention. [Figure 7] Schematic view of the cross-sectional view taken along the line A-A in FIG. 3.
Mode for Carrying Out the Invention
[0015] Hereinafter, the screw cap 100 according to an embodiment of the present invention will be described based on the drawings. In FIG. 7, among the protrusions 124 for forming a flow path that are not in contact with the outer surface of the container jaw portion Bc, the portion located axially above the contact portion between the container jaw portion Bc and the protrusion 124 for forming a flow path is shown by a solid line, and the portion located axially below the contact portion between the container jaw portion Bc and the protrusion 124 for forming a flow path is shown by a dotted line.
[0016] As shown in FIGS. 1 to 4, the screw cap 100 according to an embodiment of the present invention has a tamper-evident band 120 and is attached to the mouth portion Bm of the container B, and includes a cap body 110 and a tamper-evident band 120 connected to the lower portion of the cap body 110 via a weakened portion 122.
[0017] As shown in Figures 3 and 4, the container B to which the screw cap 100 is attached has a cylindrical opening Bm and a main body (not shown) connected to the lower part of the opening Bm. The mouth portion Bm has a container-side threaded portion Bs formed on the outer circumferential surface of the mouth portion Bm, and a container jaw portion Bc that protrudes radially outward from below the container-side threaded portion Bs of the mouth portion Bm.
[0018] The cap body 110 has a cap top surface 111 and a skirt wall 114 that hangs down from the outer edge of the cap top surface 111. An annular inner ring 112 and an outer ring 113 extending downward are formed on the lower surface of the cap top surface 111, and a small ring 117 with a flattened lower surface is formed between the inner ring 112 and the outer ring 113. The inner circumferential surface of the skirt wall 114 has a cap-side threaded portion 115 that can engage with the container-side threaded portion Bs, and the outer circumferential surface of the skirt wall 114 has a knurl 116 extending in the vertical direction formed around its entire circumference.
[0019] The tamper-evident band 120 has a cylindrical band body 121 and a plurality of weakening portions 122 provided at circumferential intervals, which connect the upper end of the band body 121 to the lower end of the skirt wall 114. The inner circumferential surface of the band body 121 is formed with a locking projection 123 that can engage with the lower side of the container jaw Bc of the container B, and a channel-forming projection 124 that abuts against the outer surface of the container jaw Bc at a position above the locking projection 123, thereby forming a space S that serves as a flow path for washing water between the container jaw Bc and the inner circumferential surface of the skirt wall 114. Multiple locking projections 123 are arranged at equal intervals along the circumferential direction of the inner surface of the band body 121. Furthermore, an inclined surface 125 is formed on the upper surface of each locking projection 123, with the inner diameter gradually decreasing from top to bottom as they connect.
[0020] Multiple channel-forming protrusions 124 are arranged at equal intervals along the circumferential direction of the inner surface of the band body 121, and are formed to extend inclined to the same side as the side on which the cap-side threaded portion 115 inclined with respect to the circumferential direction of the inner surface of the cap body 110. In this embodiment, the flow path forming projection 124 is formed so as to extend inclined at the same angle as the inclination angle of the cap-side threaded portion 115 with respect to the circumferential direction of the inner surface of the band body 121. Furthermore, when viewed in the axial direction of the band body 121, the projections 124 for forming flow paths are formed to span the distance between adjacent locking protrusions 123, and it is preferable that the circumferential length Pa of each flow path forming projection 124 extends at an angle of 10° to 60°, which is approximately the same as the control width of the tightening angle of the screw cap 100 relative to the opening Bm. In this embodiment, as shown in Figure 6, each channel-forming projection 124 is formed so that its circumferential length Pa extends at 53°, that is, the angle between both ends of the channel-forming projection 124 and the center O of the band body 121 is 53°, and each has the same circumferential length Pa. Furthermore, the channel-forming projection 124 and the upper end of the inclined surface 125 are formed to extend with a gap G in the axial direction.
[0021] As for the specific dimensions of the flow channel forming projection 124, as shown in Figure 2, it is preferable that the radial projection height Ph is 0.05 mm or more and 1.0 mm or less in order to ensure radial height in space S while suppressing deformation of the band body 121 and mounting resistance when attaching the screw cap 100 to the opening Bm. Furthermore, in order to prevent the flow channel forming projection 124 from being crushed when the screw cap 100 is attached to the opening Bm, and to suppress deformation of the band body 121 and attachment resistance, it is preferable that the axial width Pw is 0.30 mm or more and 2.0 mm or less.
[0022] Next, the attachment of the screw cap 100 according to one embodiment of the present invention to the mouth Bm of container B will be explained based on Figures 3 and 7. First, the screw cap 100 is moved above the opening Bm of container B. Then, while pressing the screw cap 100 against the opening Bm, it is rotated in the closing direction. This causes the screw portion 115 on the cap side and the screw portion Bs on the container side to engage, and the screw cap 100 rotates and descends. Next, as each channel-forming projection 124 comes into contact with the outer surface of the container jaw Bc, a space S that serves as a channel for washing water is formed in the vicinity of the circumferential direction of the contact point between each channel-forming projection 124 and the outer surface of the container jaw Bc, as shown in Figure 7. Space S consists of space S1, which is formed to the left of the contact point between the channel-forming projection 124 and the outer surface of the container jaw Bc in Figure 7, and space S2, which is formed to the right of that point. At this time, each channel-forming projection 124 is formed to extend at the same angle of inclination as the inclination angle of the cap-side screw portion 115 with respect to the circumferential direction of the inner surface of the band body 121. As a result, when it rotates and descends, the area in contact with the container jaw portion Bc of the channel-forming projection 124 does not change, and fluctuations in the circumferential compressive force due to the force received by the channel-forming projection 124 in the rotational direction are suppressed. This reduces sliding resistance and makes it easier to attach to the mouth portion Bm. Subsequently, the opening Bm is positioned between the outer surface of the inner ring 112 and the inner surface of the outer ring 113, and its descent stops when the upper end of the opening Bm comes into contact with the lower end of the small ring 117, ensuring a seal of the opening Bm and completing the installation. In this case, if the crimping angle of the screw cap 100 relative to the container B is within a predetermined tolerance range, the circumferential end of the flow channel forming projection 124 can be prevented from being located at the contact point with the container jaw Bc, thereby preventing it from being subjected to excessive localized stress and suppressing the collapse of the flow channel forming projection 124.
[0023] Next, the function of draining residual wash water from the screw cap 100 according to one embodiment of the present invention will be explained based on Figures 4 and 7. First, when the screw cap 100 is attached to the mouth Bm of container B, if cleaning water W remains on the upper part of the container jaw Bc, spaces S1 and S2 are formed in the vicinity of the contact points between each flow path forming projection 124 and the outer surface of the container jaw Bc in the circumferential direction. Therefore, the cleaning water W flows through spaces S1 and / or S2, down from the container jaw Bc, and is discharged to the outside. At this time, the washing water W remaining on the upper part of the channel-forming projection 124 flows towards the space S2 because the channel-forming projection 124 is formed at an incline, making it possible to discharge the washing water W from the space S2 more efficiently. Furthermore, the flow path forming projection 124 is formed to span the gap between adjacent locking projections 123 when viewed in the axial direction of the band body 121, thereby enabling efficient discharge of the washing water W that has passed through space S1 and / or space S2 from the circumferential gap portion of the locking projection 123. Furthermore, by blowing air through the gaps between the weakened portions 122, which are spaced apart in the circumferential direction, it is possible to push out and discharge the cleaning water W from the space S with air.
[0024] Next, the opening operation of the screw cap 100 according to one embodiment of the present invention, starting from the opening Bm, will be explained based on Figures 2 and 3. First, with the screw cap 100 attached to the opening Bm of container B, when the screw cap 100 is rotated in the opening direction, the engagement between the screw portion 115 on the cap side and the screw portion Bs on the container side is released, and the screw cap 100 begins to rise in the direction of detaching from the opening Bm. The cap body 110 rises as the screw cap 100 rotates, but the tamper evident band 120's upward movement is restricted because the upper part of the locking projection 123 interferes with the lower part of the container jaw Bc. At this time, as shown in Figure 2, the flow path forming projection 124 is formed to extend at an axial distance G from the upper end of the inclined surface 125. As a result, the tamper evident band 120 gradually rises from a state where the container jaw Bc and the upper end of the inclined surface 125 are in uniform contact around the entire circumference, and the lower side of the container jaw Bc and the locking projection 123 can engage uniformly around the entire circumference. This suppresses a sudden increase in the opening torque when opening the bottle and prevents the band body 121 from slipping off. The restriction on the upward movement of the tamper-evident band 120 causes a force to be applied in a direction that causes the weakened portion 122 connecting the cap body 110 and the tamper-evident band 120 to break. Once all of the weakened portions 112 have broken, the tamper-evident band 120 remains on the opening Bm, and only the cap body 110 detaches from the opening Bm, completing the opening process.
[0025] Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various design modifications can be made without departing from the present invention as described in the claims. In the above-described embodiment, an inclined surface 125 is formed on the upper surface of each locking projection 123, with the inner diameter gradually decreasing from top to bottom as they connect. However, the inclined surface 125 is not limited to the above shape, and may include, for example, an arc-shaped surface or a surface with a protruding part. At the very least, it should be a shape that can suppress a sudden increase in the opening torque when opening the cap. [Explanation of symbols]
[0026] 100 ··· Screw cap 110 ··· Cap body 111... Top of cap 112 ··· Inner Ring 113 ··· Outer Ring 114 ··· Skirt wall 115 ··· Cap side threaded section 116 ··· Naal 117 ··· Small Ring 120 ··· Tamper-evident band 121... Band body 122... Weakened part 123... Locking protrusion 124 ··· Protrusion for forming flow channels 125... Slope B...container Bm...mouth Bs ··· Container side threaded section Bc...Container jaw S...space S1... Space S2... space Ph... Radial projection height of the channel-forming protrusion Pw ··· Axial width of the projection for forming the flow path Pa... Circumferential length of the projection for forming the flow path W ··· Cleaning water G... interval O... Center of the band
Claims
1. A screw cap having a cap body and a tamper-evident band connected to the lower part of the cap body, The cap body has a top surface, a skirt wall hanging down from the outer peripheral edge of the top surface, and a cap-side threaded portion formed on the inner peripheral surface of the skirt wall. The tamper-evident band comprises a cylindrical band body and a weakening portion that connects the upper end of the band body to the lower end of the skirt wall. The inner circumferential surface of the band body is provided with a locking projection that can engage with the lower side of the container jaw, and a channel-forming projection that abuts against the outer surface of the container jaw at a position above the locking projection, thereby forming a space that serves as a flow path for cleaning water between the container jaw and the inner circumferential surface of the skirt wall. The screw cap is characterized in that the channel-forming projection is formed such that it extends inclined in the same direction as the cap-side threaded portion inclined with respect to the circumferential direction of the inner surface of the band body.
2. The screw cap according to claim 1, characterized in that the channel-forming protrusions are arranged in a plurality at intervals in the circumferential direction, and when viewed in the axial direction of the band body, the circumferential length of each channel-forming protrusion extends at an angle of 10° to 60°.
3. Multiple locking protrusions are arranged at intervals in the circumferential direction. The screw cap according to claim 1, characterized in that the channel-forming projection is formed to span the distance between adjacent locking protrusions when viewed in the axial direction of the band body.
4. The screw cap according to claim 2, characterized in that the channel-forming projection is formed to extend inclined in the circumferential direction of the inner surface of the band body at the same inclination angle as the inclination angle of the cap-side screw portion with respect to the circumferential direction of the inner surface of the cap body, and each projection has the same circumferential length.
5. An inclined surface is formed on the upper surface of the locking projection, with the inner diameter gradually decreasing from top to bottom as it connects. The screw cap according to claim 1, characterized in that the channel forming projection is formed to extend at an axial distance from the upper end of the inclined surface.
6. The screw cap according to claim 1, characterized in that the channel-forming projection has a protruding height of 0.05 mm or more and 1.0 mm or less, and an axial width of 0.30 mm or more and 2.0 mm or less.
7. A screw-capped container having a cylindrical opening and a main body connected to the lower part of the opening, wherein a screw cap according to any one of claims 1 to 6 is attached to the opening, The mouth portion has a container-side threaded portion formed on the outer circumferential surface of the mouth portion, and a container jaw portion that protrudes radially outward from below the container-side threaded portion of the mouth portion. A container with a screw cap, characterized in that the container-side threaded portion can be screw-engaged with the cap-side threaded portion.