Container lid made of synthetic resin

Abstract

To provide a new synthetic resin-made container lid which can prevent breakage of hinge means 8 as much as possible when impact is applied to an upper lid 6 from a side opposite to the hinge means 8.SOLUTION: A reinforcement part 62 for locally increasing an outer diameter of a cylindrical wall 60 is provided in a part on a side opposite in a diameter direction with respect to hinge means 8 on an outer peripheral surface of the cylindrical wall 60.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a synthetic resin container lid including a main body attached to the mouth-neck portion of a container and an upper lid connected to the main body via hinge means. Relates to.

Background Art

[0002] Conventionally, as a container lid capable of discharging the contents of a container containing a liquid such as a liquid seasoning little by little, a container lid provided with a slit valve as disclosed in Patent Document 1 below is well-known. Patent Document 1 below discloses a synthetic resin container lid including a main body having a circular closing wall and a cylindrical hanging wall hanging from the outer peripheral edge of the closing wall, and an upper lid having a circular top wall and a cylindrical skirt wall hanging from the outer peripheral edge of the top wall. The upper lid and the main body are connected via hinge means, and the upper lid is rotatable between a closed position covering the closing wall of the main body and an open position exposing the closing wall. A cylindrical protruding wall having a circular cross-section protruding upward is formed on the closing wall, and a cylindrical wall hanging downward is formed on the lower surface of the top lid. When the upper lid is in the closed position, the inner peripheral surface of the cylindrical wall faces and is close to or in contact with the outer peripheral surface of the protruding wall. The slit valve is attached inside the protruding wall.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the container lid as described above disclosed in Patent Document 1, due to the fact that the main body and the upper lid are connected via hinge means, there are the following problems to be solved. That is, when the container lid is attached to the mouth-neck portion of the container containing the contents and the container lid drops together with the container, and the side opposite to the hinge means on the upper lid, more specifically, the top wall of the upper lid collides with the ground, the impact caused by such a collision acts so that the upper lid is displaced laterally with respect to the main body, and the hinge means connecting the two may be broken. In a container lid in which the main body and the upper lid are connected via hinge means, usually, a flange portion protruding radially outward is formed on the outer peripheral surface of the top wall on the diametrically opposite side of the hinge means, so when the container lid drops together with the container, the flange portion collides with the ground and the upper lid often receives an impact from the flange portion. Especially when the container lid is molded from a relatively hard material such as polypropylene, the followability to deformation is poor and it is easily damaged.

[0005] The present invention has been made in view of the above facts, and its main technical problem is to provide a novel and improved synthetic resin container lid that can prevent the hinge means from being broken as much as possible when an impact is applied to the upper lid from the side opposite to the hinge means.

Means for Solving the Problems

[0006] As a result of intensive studies, the present inventors have found that the above main technical problem can be achieved by providing a reinforcing portion that locally increases the outer diameter of the cylindrical wall at a portion of the outer peripheral surface of the cylindrical wall that is diametrically opposite to the hinge means.

[0007] That is, according to the present invention, as a synthetic resin container lid that achieves the above main technical problem, it includes a main body having a circular closing wall and a cylindrical hanging wall hanging from the outer peripheral edge of the closing wall, and an upper lid having a circular top wall and a cylindrical skirt wall hanging from the outer peripheral edge of the top wall. The upper lid and the main body are connected via hinge means, and the upper lid is rotatable between a closed position covering the closing wall of the main body and an open position exposing the closing wall. The closing wall is formed with a cylindrical protruding wall having a circular cross-section that protrudes upward, and the lower surface of the top cover is formed with a cylindrical wall that hangs downward. In the synthetic resin container lid where the inner peripheral surface of the cylindrical wall faces and is close to or in contact with the outer peripheral surface of the protruding wall when the upper lid is in the closed position, A reinforcing portion that locally increases the outer diameter of the cylindrical wall is provided at a portion of the outer peripheral surface of the cylindrical wall that is diametrically opposite to the hinge means. and the reinforcing portion is continuously provided in the circumferential direction on the outer peripheral surface of the cylindrical wall, and the radial wall thickness of the cylindrical wall is the thickest at the angular position diametrically opposite to the hinge means, and gradually decreases from the angular position toward both sides in the circumferential direction. There is provided a synthetic resin container lid characterized by this.

[0008] It is preferable that a flange portion protruding radially outward is formed on the outer peripheral surface of the top wall that is diametrically opposite to the hinge means. The material is preferably polypropylene. Preferably, the protruding wall has a frustum of a cone shape. It is convenient that a slit valve is mounted inside the protruding wall. 。

Effect of the Invention

[0009] According to the synthetic resin container lid configured according to the present invention, a reinforcing portion that locally increases the outer diameter of the cylindrical wall is provided at a portion of the outer peripheral surface of the cylindrical wall that is diametrically opposite to the hinge means. Since the rigidity of the cylindrical wall at the portion where the reinforcing portion is provided is enhanced, even when an impact is applied to the upper lid from the side opposite to the hinge means, the cylindrical wall does not deform and its inner peripheral surface comes into contact with the outer peripheral surface of the protruding wall, and the lateral movement of the upper lid with respect to the main body is restricted, and the breakage of the hinge means is prevented as much as possible.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Best Mode for Carrying Out the Invention

[0011] Hereinafter, with reference to the accompanying drawings showing preferred embodiments of a synthetic resin container lid configured according to the present invention, it will be described in more detail.

[0012] Referring to FIGS. 1 and 2, the container lid indicated as a whole by reference numeral 2 includes a main body 4 and an upper lid 6, and both are connected via hinge means 8. In the illustrated embodiment, the hinge means 8 is composed of a one-side hinge portion 8a and the other-side hinge portion 8b arranged at intervals in the circumferential direction. The container lid 2 is integrally molded by injection molding an appropriate synthetic resin such as polypropylene in the state shown in FIGS. 1 and 2 (such a state is a state where the upper lid 6 is in an open position described later with respect to the main body 4).

[0013] Continuing the description with reference to FIGS. 1 and 2, the main body 4 has a circular closing wall 10 and a cylindrical hanging wall 12 hanging down from the outer peripheral edge of the closing wall 10. In the central portion of the closing wall 10, a cylindrical protruding wall 14 having a circular cross-section protruding upward is formed, and a circular discharge port 16 is provided on the upper surface of the protruding wall 14. In the illustrated embodiment, the protruding wall 14 has a frustum of a cone shape, and its upper end surface 18 has a flat annular shape. A cylindrical hanging piece 20 hanging downward toward the radially inner side is connected to the inner peripheral edge of the upper end surface 18. On the inner peripheral surface of the upper end portion of the protruding wall 14, a holding ridge 22 protruding toward the radially inner side is continuously formed in the circumferential direction. In the illustrated embodiment, a slit valve 24 is mounted inside the protruding wall 14. The slit valve 24 is composed of a valve body 26 formed from a relatively soft synthetic resin and closing the discharge port 16 below it, and an annular valve holding portion 28 made of synthetic resin for supporting the valve body 26. The valve holding portion 28 is held by the holding ridge 22 inside the protruding wall 14, and the valve body 26 is clamped by the valve holding portion 28 and the protruding wall 14. The valve body 26 is circular in plan view and a cross-shaped slit 30 is formed in its central portion (see FIG. 1). When the internal pressure of the container with the container lid 2 attached rises, the valve body 26 bulges upward in a dome shape, opening the slit 30 and enabling the discharge of the contents. Since such a configuration of the slit valve is well-known, detailed description of the slit valve will be omitted in this specification. If desired, instead of the slit valve, a check valve as disclosed in, for example, Japanese Patent Application Laid-Open No. 2019-182531, which was filed and published earlier than this application by the applicant of this application, may be mounted inside the protruding wall 14. Note that mounting a valve inside the protruding wall 14 is not necessarily essential depending on the intended use and the like.

[0014] On the outer peripheral edge of the upper surface of the closing wall 10, a cylindrical locking wall 32 that protrudes upward toward the outer side in the radial direction is formed. On the outer peripheral surface of the upper end of the locking wall 32, a circumferentially continuous locking ridge 34 is formed. In the radial middle part of the lower surface of the closing wall 10, a cylindrical sealing wall 36 that hangs downward is formed. On the outer peripheral edge of the lower surface of the closing wall 10, a cylindrical mounting wall 38 that hangs downward is provided. On the inner peripheral surface of the mounting wall 38, a female thread 40 is formed. On the outer peripheral surface of the mounting wall 38, two columnar extension pieces 42 that extend linearly downward from the lower surface of the closing wall 10 and beyond the lower end of the mounting wall 38 are also provided. The two extension pieces 42 are provided one on each side in the diameter direction. One end of the hinge means 8 is connected to the upper end of the outer peripheral surface of the hanging wall 12. In a small circumferential area between the one-side hinge part 8a and the other-side hinge part 8b at the upper end of the outer peripheral surface of the hanging wall 12, a substantially rectangular notch 44 is provided. In a part of the upper end of the outer peripheral surface of the hanging wall 12 opposite to the hinge means 8, an arc-shaped recess 46 with a locally reduced outer diameter is provided.

[0015] The upper lid 6 has a circular top wall 48 and a cylindrical skirt wall 50 that hangs down from the outer peripheral edge of the top wall 48, and is rotatable between a closed position (the state shown in FIGS. 3 and 4) that covers the closing wall 10 of the main body 4 and an open position (the state shown in FIGS. 1 and 2) that exposes the closing wall 10. The up-and-down direction of the upper lid 6 in this specification is based on when the upper lid 6 is in the closed position. The other end of the hinge means 8 is connected to the lower end of the outer peripheral surface of the skirt wall 50. In a small circumferential area between the one-side hinge part 8a and the other-side hinge part 8b of the upper lid 6, an L-shaped notch 52 is provided from the outer peripheral edge of the top wall 48 across the entire skirt wall 50 (see FIG. 2). The radially outer end face of the top wall 48 that defines the radially inner end of the notch 52 and the upper end face of the hanging wall 12 that defines the lower end of the notch 44 are connected by an L-shaped connecting piece 54. As can be understood by comparing FIGS. 2 and 4, the connecting piece 54 is aligned with the notch 44 and the notch 52 when the upper lid 6 is in the closed position.

[0016] On the side of the hinge means 8 on the lower surface of the top surface wall 48, a rib 56 protruding downward is formed. As shown in FIG. 4, the radially outer surface of the rib 56 faces and is close to or in contact with the inner peripheral surface of the protruding wall 14 on the side where the hinge means 8 is present when the upper lid 6 is in the closed position. In the illustrated embodiment, a cylindrical pin 58 protruding downward is formed at the center of the lower surface of the top surface wall 48. The pin 58 enters the inside of the protruding wall 14 when the upper lid 6 is pivoted from the open position to the closed position. At this time, although detailed description is omitted, the pin 58 presses the upper surface of the valve body 26 bulged upward downward during the discharge of the contents, promoting the return of the valve body 26 bulged upward to its original state, that is, the state shown in FIG. 4. And when the upper lid 6 is in the closed position, the pin 58 is positioned close to the upper surface of the valve body 26. Although detailed description is omitted, the pin 58 promotes the return of the valve body 26 bulged upward to its original state, that is, the state shown in FIG. 4 during the discharge of the contents. The rib 56 protrudes downward from the lower surface of the top surface wall 48 and is connected to the outer peripheral surface of the pin 58. As shown in FIG. 1, the rib 56 is connected to the outer peripheral surface of the pin 58 on the side where the hinge means 8 is present, is located on the diameter passing through the circumferential center of the hinge means 8, and is also provided one by one at intervals on both circumferential sides of such a position. Therefore, in the illustrated embodiment, three ribs 56 are provided at intervals in the circumferential direction. If desired, the rib 56 arranged on the diameter passing through the circumferential center of the hinge means 8 may be omitted, or the other two ribs 56 arranged on both circumferential sides of such a rib 56 may be omitted while leaving such a rib 56. The rib 56 is plate-shaped as shown in FIGS. 2 and 4, and the radial length of the base end portion 56a is longer than the radial length of the tip end portion 56b. The base end portion 56a is linearly inclined downward from the lower surface of the top surface wall 48 toward the radially inner side, and the tip end portion 56b extends substantially horizontally after hanging vertically downward from the lower end of the base end portion 56a and is connected to the outer peripheral surface of the pin 58. As shown in FIG. 4, in the illustrated embodiment, when the upper lid 6 is in the closed position, the radially outer surface of the tip end portion 56b of the rib 56 is close to or in contact with the inner peripheral surface of the protruding wall 14, and the lower surface of the base end portion 56a of the rib 56 is close to or in contact with the upper surface of the protruding wall 14.

[0017] On the lower surface of the top surface wall 48, a cylindrical wall 60 that hangs downward is also formed. The cylindrical wall 60 is formed concentrically with the pin 58 on the radially outer side of the rib 56, and the lower end of the cylindrical wall 60 is located below the lower end of the rib 56 and above the lower end of the pin 58 when viewed in the vertical direction. As shown in FIG. 4, when the upper lid 6 is in the closed position, the lower end portion of the inner peripheral surface of the cylindrical wall 60 abuts against the upper portion of the outer peripheral surface of the protruding wall 14 over the entire circumferential direction, preventing the contents described later from leaking from the inside of the protruding wall 14. And it is important that a reinforcing portion 62 that locally increases the outer diameter of the cylindrical wall 60 is provided at a portion of the outer peripheral surface of the cylindrical wall 60 diametrically opposite to the hinge means 8. As can be understood by referring to FIG. 1 together with FIG. 2, the reinforcing portion 62 is provided continuously in the circumferential direction on the outer peripheral surface of the cylindrical wall 60, and the radial wall thickness of the cylindrical wall 60 is the thickest at the angular position diametrically opposite to the hinge means 8, and gradually decreases from such an angular position toward both sides in the circumferential direction. 。

[0018] On the outer peripheral surface of the top surface wall 48 diametrically opposite to the hinge means 8, a flange portion 64 that protrudes outward in the radial direction is formed. The flange portion 64 is provided continuously in the circumferential direction on the outer peripheral surface of the top surface wall 48, and the amount of protrusion from the outer peripheral surface of the top surface wall 48 is the largest at the angular position diametrically opposite to the hinge means 8, and gradually decreases from such an angular position toward both sides in the circumferential direction. On the lower end portion of the inner peripheral surface of the skirt wall 50, two circumferentially extending locking ridges 66a and 66b are provided at intervals in the circumferential direction. The locking ridge 66a is longer in the circumferential length than the locking ridge 66b, and the locking ridge 66a is provided on the flange portion 64 side, and the locking ridge 66b is provided on the hinge means 8 side, respectively. The locking ridges 66a and 66b are elastically locked to the locking ridge 34 of the main body 4 when the upper lid 6 is in the closed position. At a required portion of the outer peripheral surface of the skirt wall 50, a bulging portion 68 is also provided whose outer diameter gradually increases toward the flange portion 64 provided on the outer peripheral surface of the top surface wall 48 and is smoothly connected to the lower surface of the flange portion 64.

[0019] Figure 4 also shows, in dashed double-dotted lines, the neck portion of the container to which such a container lid 2 configured according to the present invention is applied, together with the container lid 2. The neck portion 70 of the container, which can be formed from an appropriate synthetic resin, has a cylindrical shape with an open upper surface, and male threads 72 are formed at the upper end portion of its outer peripheral surface. In the illustrated embodiment, a slit valve 24 is attached to the container lid 2. Since it is necessary to deform the outer shape of the container to increase the internal pressure of the container in order to discharge the contents, the container is molded from a relatively soft synthetic resin. However, when no valve is attached to the container lid 2, the container may be made of a hard synthetic resin or glass.

[0020] When the container lid 2 is attached to the neck portion 70 to seal the neck portion 70 after the contents are accommodated in the container, the container lid 2 is fitted onto the neck portion 70 and rotated clockwise when viewed from above. In this way, due to the screwing engagement between the female threads 40 of the container lid 2 and the male threads 72 of the neck portion 70, the container lid 2 gradually descends with respect to the neck portion 70, and the seal wall 36 enters the inside of the neck portion 70 and its outer peripheral surface is brought into close contact with the inner peripheral surface of the neck portion 70, thereby sealing the neck portion 70. The above screwing engagement is stopped when the extension piece 42 abuts against a stopper (not shown) provided on the neck portion 70. Thus, the container lid 2 is attached to the neck portion 70.

[0021] According to the synthetic resin container lid configured according to the present invention, a reinforcing portion 62 that locally increases the outer diameter of the cylindrical wall 60 is provided at a portion diametrically opposite to the hinge means 8 on the outer peripheral surface of the cylindrical wall 60. Since the rigidity of the cylindrical wall 60 at the portion where the reinforcing portion 62 is provided is enhanced, even when an impact is applied to the upper lid 6 from the side opposite to the hinge means 8, the cylindrical wall 60 does not deform and its inner peripheral surface comes into contact with the outer peripheral surface of the protruding wall 14, and the lateral movement of the upper lid 6 with respect to the main body 4 is restricted, and the breakage of the hinge means 8 is prevented as much as possible.

[0022] <Example> A polypropylene container lid with a nominal diameter of 30 mm in the form shown in FIGS. 1 to 4 was injection molded. A slit valve as shown in FIG. 2 etc. is also attached inside the protruding wall 14 of such a container lid. In the cylindrical wall 60, the radial wall thickness at the angular position diametrically opposite to the hinge means 8 is maximum at 1.4 mm, and the radial wall thickness at the angular position diametrically opposite to the above angular position, that is, on the side where the hinge means 8 is provided, is minimum at 0.75 mm.

[0023] Ten polyethylene terephthalate containers each having a neck portion as shown by the two-dot chain line in FIG. 4 were filled with water, and then the above container lid was attached to the neck portion to seal the neck portion. Ten containers filled with water and with the container lid attached were subjected to a drop impact test in a 5°C environment. In such a drop impact test, the container was set in a slightly inclined state from the upright state and dropped from a required height, and first the bottom of the container collided with an iron plate floor surface, and then the side opposite to the hinge means on the upper lid of the container lid collided with the above floor surface. Thereafter, the presence or absence of damage to the hinge means was inspected. The results were as shown in Table 1 below.

[0024] <Comparative Example> A drop impact test was carried out in the same manner as in the example except that the radial wall thickness of the cylindrical wall 60 was 0.75 mm throughout the circumferential direction. The results were as shown in Table 1 below.

[0025]

Table 1

[0026] As can be understood by referring to Table 1 above, by increasing the radial wall thickness at the angular position diametrically opposite to the hinge means 8 in the cylindrical wall 60, it is confirmed that the drop impact resistance characteristics against the hinge means 8 are improved when an impact is applied to the upper lid 6 from the side opposite to the hinge means 8.

Explanation of Reference Numerals

[0027] 2: Container lid 4: Body 6: Upper lid 8: Hinge means 10: Closing wall 12: Hanging wall 14: Protruding wall 48: Top wall 50: Skirt wall 60: Cylindrical wall 62: Reinforcing part

Claims

1. A container lid made of synthetic resin, comprising a main body having a circular closing wall and a cylindrical hanging wall hanging down from the outer peripheral edge of the closing wall, and an upper lid having a circular top wall and a cylindrical skirt wall hanging down from the outer peripheral edge of the top wall. The upper lid and the main body are connected via hinge means, and the upper lid is rotatable between a closed position covering the closing wall of the main body and an open position exposing the closing wall. A cylindrical protruding wall with a circular cross-section protruding upward is formed on the closing wall, and a cylindrical wall hanging downward is formed on the lower surface of the top lid. When the upper lid is in the closed position, in the synthetic resin container lid where the inner peripheral surface of the cylindrical wall faces and is close to or in contact with the outer peripheral surface of the protruding wall. A reinforcing portion that locally increases the outer diameter of the cylindrical wall is provided at a portion of the outer peripheral surface of the cylindrical wall diametrically opposite to the hinge means. The reinforcing portion is continuously provided in the circumferential direction on the outer peripheral surface of the cylindrical wall. The radial wall thickness of the cylindrical wall is thickest at the angular position diametrically opposite to the hinge means, and gradually decreases toward both sides in the circumferential direction from the angular position. The synthetic resin container lid is characterized by this.

2. The synthetic resin container lid according to claim 1, wherein a flange portion protruding radially outward is formed on the outer peripheral surface of the top wall diametrically opposite to the hinge means.

3. The synthetic resin container lid according to claim 1 or 2, wherein the material is polypropylene.

4. The synthetic resin container lid according to any one of claims 1 to 3, wherein the protruding wall has a frustum of a cone shape.

5. The synthetic resin container lid according to any one of claims 1 to 4, wherein a slit valve is mounted inside the protruding wall.

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