Container lid

Abstract

To provide a container lid which can prevent cracks from occurring by dispersing external forces acting on the container lid without concentrating them on specific points, even when a material such as biaxially oriented polystyrene that easily cracks is used. [Solution] The container lid L is a container lid made of a synthetic resin sheet that covers the top opening of the container body, and has a top plate portion 1 with a flat portion and side wall portions 2a to 2d that extend downward from the periphery of the top plate portion 1, and the side wall portions 2a to 2d have trapezoidal first protrusions 21a to 21f that protrude outward at a predetermined interval in the circumferential direction and extend upward from the lower end of the side wall portions 2a to 2d to a height that does not reach the upper end.

Description

[Technical Field]

[0001] The present invention relates to a container lid that covers the top opening of a container body. [Background technology]

[0002] The lids of packaging containers are required to have certain characteristics such as allowing the food or the like contained in the container to be seen, being lightweight, easy to mold, strong, and non-breakable. Heat resistance is also required as necessary.

[0003] For example, Patent Document 1 proposes a container lid that has the necessary strength without being excessively thick and has excellent visibility, and that has a polygonal, flat top surface, a hanging surface that hangs downward from the peripheral edge of the top surface, an inclined side surface that extends downward and outward, and a flange that extends outward from the inclined side surface, with the lower end of the hanging surface and the upper end of the inclined side surface connected via a horizontal surface that extends horizontally, and the width of the horizontal surface gradually narrows from both corners to the center of each of the pair of long sides.

[0004] Furthermore, as a lid body that does not lose its appearance due to deformation and has sufficient strength to withstand loads on the top plate portion, for example, Patent Document 2 proposes a lid body for a packaging container that is polygonal in shape when viewed from above, and has a top plate portion with a flat portion, a side wall portion connected to the top plate portion, and a flange portion connected to the side wall portion, in which anti-slip protrusions are provided at the corners of the polygon of the top plate portion along each side that forms the corners, and a boundary recess is provided at the boundary between the flat portion of the top plate portion and the anti-slip protrusions, which is recessed in the direction opposite to the protruding direction of the anti-slip protrusions. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2019-18869 [Patent Document 2] JP 2013-67400 A Summary of the Invention [Problem to be solved by the invention]

[0006] Biaxially oriented polystyrene (OPS) is widely used as a material for container closures because it has transparency, rigidity, dimensional stability, heat resistance, and is easy to mold. Although OPS is significantly less likely to crack than unstretched polystyrene, it still has issues with its fragility (brittleness). It is said that cracks are particularly likely to occur in thin-walled sections, corners, and in low-temperature environments.

[0007] Therefore, the object of this invention is to provide a container lid that can distribute the external forces acting on the container lid without concentrating them in a specific area, thereby suppressing the occurrence of cracks, even when using a material that is prone to cracking, such as OPS. [Means for solving the problem]

[0008] A container lid according to one embodiment of the present invention that achieves the above-mentioned object is a container lid made of a synthetic resin sheet that covers the top opening of a container body, and has a top plate portion having a flat portion, a side wall portion extending downward from the periphery of the top plate portion, and a first horizontal portion extending horizontally outward from the lower end of the side wall portion, and the side wall portion has a plurality of first protruding portions that are rectangular or semicircular and protrude outward at a predetermined interval around the circumference, extending from the lower end of the side wall portion upward to a height that does not reach the upper end.

[0009] In the container lid having the above configuration, it is preferable that the outward protrusion of the first protrusion is 1 mm or less.

[0010] In the container lid having the above configuration, it is preferable that the first protrusion has a trapezoidal shape when viewed from a direction perpendicular to the side wall portion.

[0011] In the container lid having the above configuration, the top plate portion may have a second protruding portion that protrudes upward and regulates the position of the bottom plate of the container body stacked above.

[0012] In the container lid having the above configuration, it is preferable that the top plate portion is quadrangular in plan view, and the side wall portion has a semicircular cone-shaped first recess protruding inward at each of the four corners.

[0013] Furthermore, the container lid of the above configuration may further have a first horizontal portion extending horizontally outward from the lower end of the side wall portion, and a skirt portion extending downward from the outer peripheral edge of the first horizontal portion, and the skirt portion may have a plurality of second recesses protruding inward at a predetermined distance below the upper end, spaced at predetermined intervals in the circumferential direction, so that when the top opening of the container body is covered, a flange portion formed on the outer peripheral edge of the top opening of the container body is fitted between the second recesses and the first horizontal portion.

[0014] In the container lid having the above-described structure, the synthetic resin sheet is preferably a sheet made of polystyrene resin. [Effects of the Invention]

[0015] The container lid of the present invention can prevent cracks even when made of a fragile material such as OPS by dispersing external forces applied to the container lid without concentrating them in a specific area. In addition, the freedom of material selection is increased, and a container lid with sufficient durability can be provided while achieving weight reduction and cost reduction. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a plan view showing one embodiment of a container lid according to the present invention; [Figure 2] FIG. 2 is a right side view of the container lid of FIG. [Figure 3] FIG. 2 is a rear side view of the container lid of FIG. 1. [Figure 4] FIG. 2 is a partially enlarged cross-sectional view showing the container lid attached to the container body. DETAILED DESCRIPTION OF THE INVENTION

[0017] The following describes embodiments of the present invention, but the present invention is not limited to the following embodiments. In this specification, numerical ranges indicated using "to" indicate ranges that include the numerical values ​​before and after "to" as the minimum and maximum values, respectively. Unless otherwise specified, the materials exemplified below may be used alone or in combination of two or more types.

[0018] Fig. 1 is a plan view showing one embodiment of a container lid according to the present invention, Fig. 2 is a right side view of the container lid of Fig. 1, and Fig. 3 is a rear side view of the container lid of Fig. 1. The container lid L shown in these figures is made of a synthetic resin sheet and has, in a planar view, a flat top plate portion 1 that is rectangular in shape extending in the front-to-rear direction and has four rounded corners, side wall portions 2a, 2b, 2c, and 2d (hereinafter sometimes collectively referred to as "side wall portion 2") that slope slightly outwardly downward from the periphery of the top plate portion 1, a first horizontal portion 3 that extends horizontally outward from the lower end of the side wall portion 2, a skirt portion 4 that extends approximately vertically downward from the outer periphery of the first horizontal portion 3, and a second horizontal portion 5 that extends slightly outwardly from the lower end of the skirt portion 4.

[0019] (Top plate 1) The top plate 1 has second protrusions 11a and 11c formed along the opposing long sides and second protrusions 11b and 11d formed along the opposing short sides. These second protrusions 11a to 11d serve to regulate the position of the bottom plate of the container body B (shown in FIG. 4) stacked above. In other words, the area surrounded by these second protrusions 11a to 11d is set to be slightly larger than the shape of the bottom plate of the container body B (shown in FIG. 4).

[0020] The cross-sectional shape perpendicular to the direction in which the second protrusions 11a-11d extend is a rectangle with rounded upper corners. There is no limitation on the height of the second protrusions 11a-11d as long as it is possible to regulate the position of the bottom plate of the container body B stacked above, but it is usually preferable that it be in the range of 1 mm to 5 mm. Note that in this embodiment, the second protrusions 11a-11d are continuous ridges, but are not limited thereto and may be discontinuous ridges or may be hemispherical.

[0021] (Side wall part 2) The side wall portion 2 has long side wall portions 2a, 2c that face each other in the left-right direction and short side wall portions 2b, 2d that face each other in the front-rear direction. As shown in FIG. 2, each of the long side wall portions 2a (2c) has two first protrusions 21a, 21b (21d, 21e) spaced a predetermined distance apart in the front-rear direction. As shown in FIG. 3, each of the short side wall portions 2b, 2d has a first protrusion 21c (21f) in the center in the left-right direction. When a force is applied to the container lid L in the vertical direction, the first protrusions 21a-21f disperse the external force, preventing the force from concentrating on a specific location on the container lid L and preventing the container lid L from cracking.

[0022] The first protrusions 21a-21f have a trapezoidal shape when viewed perpendicularly to the side wall 2. The lower edges of the first protrusions 21a-21f coincide with the lower end of the side wall 2, and the upper edges of the first protrusions 21a-21f do not reach the upper end of the side wall 2. The vertical height of the first protrusions 21a-21f is not limited as long as it effectively disperses external forces, but is typically preferably in the range of 50% to 90% of the vertical height of the side wall 2. The outward protrusion amount of the first protrusions 21a-21f is also not limited as long as it effectively disperses external forces, but is preferably in the range of 1 mm or less, taking into account the appearance of the container lid L, etc. The number and positions of the first protrusions 21a-21f are not particularly limited and may be determined appropriately taking into account the planar shape and material of the top plate 1, etc.

[0023] The side wall 2 has first recesses 22a, 22b, 22c, and 22d, each of which has a semicircular cone shape and protrudes inward, at each of its four corners. The first recesses 22a to 22d function to suppress deformation of the container lid L when force is applied in the front-to-back and left-to-right directions. The shape of the first recesses 22a to 22d is not limited to a semicircular cone shape and may be a semicylindrical shape, for example. When the top plate 1 has a polygonal shape, it is preferable to provide a first recess at each of the corners. There is no limitation on the maximum inward protrusion of the first recesses 22a to 22d as long as it suppresses deformation of the container lid L, but it is generally preferable that it be in the range of 1 mm to 5 mm.

[0024] The side wall 2 has eight stack protrusions 23a-23h that protrude outward at predetermined intervals in the circumferential direction. The stack protrusions 23a-23h function to prevent the container lids L from fitting together when stacked vertically. For this reason, it is preferable to prepare multiple types of container lids L that differ in the positions and number of the stack protrusions 23a-23h.

[0025] The amount of outward protrusion of the stack protrusions 23a to 23h is preferably set to be longer than the amount of outward protrusion of the first protrusions 21a to 21f, and is usually preferably in the range of more than 1 mm to 5 mm or less. Also, the vertical height of the stack protrusions 23a to 23h is preferably set to be shorter than the vertical height of the first protrusions 21a to 21f.

[0026] (First horizontal section 3 and skirt section 4) The first horizontal portion 3 extends horizontally outward from the lower end of the side wall portion 2. The skirt portion 4 extends downward from the outer peripheral edge of the first horizontal portion 3. The skirt portion 4 has a plurality of second recesses 41 in the shape of a quadrangular pyramid that protrude inward at a position a predetermined distance below the upper end. As shown in FIG. 4 , the first horizontal portion 3 and the skirt portion 4 mainly function to detachably fix the flange portion 8 of the container body B when the container lid L is attached to the container body B.

[0027] 4, the outward extension length of the first horizontal portion 3 is approximately the same as the outward extension length of the cylindrical flange portion 8 of the container body B. The vertical length of the skirt portion 4 is longer than the vertical thickness of the flange portion 8 of the container body B, and the vertical length from the first horizontal portion 3 to the second recess 41 is the same as or slightly longer than the vertical thickness of the flange portion 8. The inward protrusion amount of the second recess 41 is shorter than the outward extension length of the flange portion 8, and is usually preferably 3 mm or less.

[0028] When the container lid L is attached to the container body B, an external force is applied to the container lid L in a direction toward the top opening 7 of the container body B. Then, the cylindrical flange portion 8 formed on the outer peripheral edge of the top opening 7 of the container body B comes into contact with the lower part of the second recess 41 of the container lid L, elastically deforming the skirt portion 4 so that it is pushed outward. After that, when the flange portion 8 clears the second recess 41, the skirt portion 4 returns to its original state due to its elasticity, and the flange portion 8 fits between the second recess 41 and the first horizontal portion 3, so that the container lid L is stably fixed to the container body B (see FIG. 4).

[0029] When the container lid L is to be removed from the container body B, an external force is applied to the container lid L in a direction away from the top opening 7 of the container body B, in the reverse of the above operation. Then, the flange portion 8 of the container body B comes into contact with the upper part of the second recessed portion 41 of the container lid L, elastically deforming the skirt portion 4 so that it is pushed outward. Thereafter, the flange portion 8 passes over the second recessed portion 41 and comes off the container lid L, and the skirt portion 4 returns to its original state due to its elasticity.

[0030] (2nd horizontal part 5) The second horizontal portion 5 extends slightly horizontally outward from the lower end of the skirt portion 4. The second horizontal portion 5 serves to improve the strength of the skirt portion 4. The second horizontal portion 5 is a part that is likely to be touched by the user's fingers, and it is preferable that the peripheral edge of the second horizontal portion 5 be knurled to prevent finger cuts.

[0031] (Manufacturing method) The container lid L according to the present invention is integrally formed by vacuum forming or vacuum-pressure forming a synthetic resin sheet. Materials that can be used for the synthetic resin sheet include polystyrene, polyethylene terephthalate, polypropylene, and polyethylene. Oriented versions of these resins, or those containing a foaming agent, can also be used. From the viewpoint of making the contents inside the container body B visible through the outer shell, a material with transparency is preferred, and rigidity, dimensional stability, heat resistance, and formability are even more preferred. OPS (biaxially oriented polystyrene), which has these properties, is a more preferred material for the synthetic resin sheet. The thickness of the synthetic resin sheet can be determined appropriately based on the shape and size of the container lid L, the material of the synthetic resin sheet, and the like, but is typically preferably in the range of 0.2 mm to 0.8 mm.

[0032] (Other variations) Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments. Addition, omission, substitution, and other modifications of the configuration are possible within the scope of the spirit of the present invention. The present invention is not limited by the above description, but is limited only by the scope of the attached utility model registration claims. For example, in the above embodiment, the top panel 1 is rectangular, but it may be a polygon such as a triangle or a pentagon, or a circle. Furthermore, the shape of the first protrusion formed on the side wall 2 is not limited to a trapezoid, and may be a polygon such as a triangle or a pentagon, or a semicircle.

[0033] Furthermore, although the container lid L in the above embodiment is an externally fitted type with respect to the container body B, it may also be an internally fitted type. Furthermore, the flange portion 8 of the container body B may be cylindrical or may be flat. [Industrial Applicability]

[0034] With the container lid of the present invention, even if a fragile material such as OPS is used, the external force applied to the container lid is dispersed without being concentrated in a specific area, thereby preventing cracks from occurring. [Explanation of symbols]

[0035] 1 Top plate 2,2a,2b,2c,2d Side wall part 3 1st horizontal section 4 Skirt section 5 2nd horizontal section 7 Top opening 8 Flange L container lid B. Container body 11a~11d 2nd protrusion 21a~21f 1st protrusion 22a to 22d First recess 41 Second recess

Claims

1. A container lid made of a synthetic resin sheet that covers the top opening of the container body, a top plate portion having a flat portion and a side wall portion extending downward from a peripheral edge of the top plate portion; A container lid characterized in that the side wall portion has a plurality of first protrusions, which are rectangular or semicircular and protrude outward at a predetermined interval in the circumferential direction, and which extend from the lower end of the side wall portion upward to a height that does not reach the upper end.

2. 2. The container lid according to claim 1, wherein the first protrusion has an outward protrusion amount of 1 mm or less.

3. The container lid according to claim 1 , wherein the first protrusion has a trapezoidal shape when viewed from a direction perpendicular to the side wall.

4. 2. The container lid according to claim 1, wherein the top plate portion has a second protruding portion that protrudes upward and regulates the position of the bottom plate of the container body stacked above.

5. 2. The container lid according to claim 1, wherein the top plate portion is rectangular in plan view, and the side wall portion has a semi-conical first recess projecting inward at each of four corners.

6. a first horizontal portion extending horizontally outward from a lower end of the side wall portion; a skirt portion extending downward from an outer peripheral edge of the first horizontal portion; the skirt portion has a plurality of second recesses protruding inward at predetermined intervals in the circumferential direction at positions below the upper end by a predetermined length, 2. The container lid according to claim 1, wherein when the top opening of the container body is covered, a flange portion formed on the outer peripheral edge of the top opening of the container body is fitted between the second recess and the first horizontal portion.

7. 2. The container lid according to claim 1, wherein the synthetic resin sheet is made of polystyrene resin.

Images