Packaging containers

Abstract

To suppress deformation of a lid flange part and enable a smooth lid closing process by a machine when applied to an automatic lid closing machine of a type that pulls downward one by one the lid located at the bottom among many stacked lids.SOLUTION: In the packaging container according to the present invention, a lid flange part comprises a lid skirt portion, a tapered extension portion extending diagonally downward and outward from the lid skirt portion, and a lid edging portion extending approximately horizontally outward from the tapered extension portion, wherein the dimension of the tapered extended portion in the inward and outward direction to the outside with respect to the lid skirt reference surface portion in a plan view is larger than the dimension of the lid edging portion in the inward and outward direction in a plan view, and the tapered extended portion 36 is provided with a large number of downward ribs 41 projecting downward at intervals in the circumferential direction over the entire circumference of the tapered extended portion 36.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a packaging container suitable for storing food, in particular one in which a lid is fitted onto the outside of the container body, and more particularly to a container suitable for automatic lid closing by an automatic lid closing machine. [Background technology]

[0002] Food ingredients such as prepared foods, chilled noodles, and boxed lunches sold in supermarkets and other stores are cooked in the back of the store and packaged in containers. Alternatively, the food is cooked in a dedicated factory, packaged in containers, and then transported to each store and displayed in front of the store. In particular, in dedicated factories, large quantities of cooked food are placed in containers, and the task of manually closing the lids on all of these containers is required. However, due to factors such as labor shortages in recent years, there is a demand for this closing process to be automated, and therefore there is a demand for packaging containers that are suitable for automatic closing machines.

[0003] In an automatic lid closing machine that removes the bottom lid one by one from a stack of many lids, for example, a stack of about 100 lids, the lid closing process mainly requires the following three steps. Step 1: The stacked lids are manually placed on the machine, and the machine's support claws support the lids. Step 2: The machine's separating claws separate the stacked lids one by one. Step 3: The isolated lid is mechanically fitted onto the container body containing the food.

[0004] The lids described in Patent Document 1 below are intended to be pulled upward by suction with a vacuum device when stacked. Therefore, although a tapered extension portion is provided outward at the lower end of the lid skirt portion of the lid flange, its dimension in the inward / outward direction is very short. Therefore, it is virtually impossible to hook a separation claw onto the tapered extension portion of the bottom lid and pull the bottom lid downward. Furthermore, the strength of the lower end of the lid skirt portion is low, which poses a problem in that the lid skirt portion and the tapered extension portion are easily deformed inward and outward when supported by a support claw.

[0005] On the other hand, in Patent Document 2 listed below, a lid skirt has a lower end provided with a lid border extending substantially horizontally outward. If this lid were used in an automatic capping machine, when the lid border of the lowest lid is supported by the support claws in step 1, the lid border may be deformed by the weight of the numerous lids stacked above. Furthermore, if the lid border is deformed in the stacked state, the lids may not be smoothly separated by the separation claws in step 2. Furthermore, when the separation claws abut against the upper surface of the lid border and apply a downward force in step 2, the lid border may be deformed downward by the separation claws. This may result in the lids not being smoothly separated. Furthermore, if the lid border is deformed, the lid may not be smoothly fitted onto the container body in step 3. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 10-120005 [Patent Document 2] Japanese Utility Model Application Publication No. 62-540 Summary of the Invention [Problem to be solved by the invention]

[0007] Therefore, the present invention aims to suppress deformation of the lid flange portion when applied to an automatic lid closing machine that pulls the bottommost lid out of a large number of stacked lids one by one, thereby enabling the lid closing process by the machine to be carried out smoothly. [Means for solving the problem]

[0008] The packaging container of the present invention is a packaging container comprising a container body having a body flange portion, and a lid having a lid flange portion that fits externally onto the body flange portion when the lid is closed, wherein the lid flange portion comprises a lid skirt portion, a tapered extension portion extending diagonally downward and outward from the lid skirt portion, and a lid edging portion extending approximately horizontally outward from the tapered extension portion, and the lid skirt portion comprises a lid skirt reference surface portion that extends approximately vertically downward, and an inward engaging protrusion that protrudes inward from the lid skirt reference surface portion and engages with the body flange portion when the lid is closed, and the outward inward / outward dimension of the tapered extension portion relative to the lid skirt reference surface portion in a planar view is greater than the inward / outward dimension of the lid edging portion in a planar view, and the tapered extension portion has a plurality of downward ribs that protrude downward and are spaced circumferentially around the entire circumference of the tapered extension portion.

[0009] According to this configuration, a tapered extension extending diagonally downward is provided at the lower end of the lid skirt, and a lid border extending approximately horizontally is provided outside the tapered extension. Therefore, the tapered extension and the lid border enhance the strength of the lower end of the lid skirt. Furthermore, although the lid border is provided, its width, i.e., its inner-outer dimension, is smaller than the width of the tapered extension. In step 1, when a large number of stacked lids are supported by the support claws of the automatic lid closing machine, the lid border abuts against the support claws. As described above, because the lid border is narrower than the tapered extension, the lid border is less likely to deform when supported by the support claws. Furthermore, when the lid border attempts to deform upward, the tapered extension located inside acts as a brace to prevent the lid border from deforming. Therefore, even when a large number of lids are stacked, deformation of the lid flange of the bottommost lid can be effectively suppressed.

[0010] Furthermore, in step 2, the lid flange is less likely to deform when the separation claw pulls the bottom lid downward. That is, because the lid trim is narrow and the tapered extension is wide, the separation claw abuts against the upper surface of the tapered extension, not the lid trim. The tapered extension is subjected to a downward force from the separation claw, which tends to deform the tapered extension inward. However, because the lid trim is located outside the tapered extension, the lid trim suppresses the inward deformation of the tapered extension. Furthermore, because the tapered extension has a downward rib, deformation of the tapered extension is suppressed even when the separation claw presses the tapered extension downward. Furthermore, because the downward rib formed on the tapered extension protrudes downward, the separation claw does not abut against the downward rib, and the downward rib itself is not crushed. Therefore, the downward rib effectively suppresses deformation of the tapered extension, and the tapered extension firmly absorbs the downward force from the separation claws. This allows the bottom lid to be smoothly pulled downward in step 2. Furthermore, because deformation of the lid flange is suppressed, the lid can be smoothly externally fitted onto the container body in step 3.

[0011] In particular, it is preferable that the downward rib has a bent portion where the upper surface is bent in a valley fold. With this configuration, the bent portion increases the strength of the downward rib itself, and as a result, the strength of the tapered extension portion can be increased.

[0012] Furthermore, it is preferable that the downward rib includes a rib bottom portion and a pair of left and right rib side portions aligned in the up-down direction, and that the bent portion is provided on the rib bottom portion and connects the left and right rib side portions. With this configuration, the left and right rib side portions form vertical walls that withstand vertical forces. Furthermore, because the left and right rib side portions are connected by the bent portion, deformation of the left and right rib side portions themselves is also prevented. Therefore, the tapered extension portion is even less likely to deform when supported by the support claws, and is even even less likely to deform when the bottom lid is separated by the separation claws.

[0013] Furthermore, the tapered extension preferably has an upwardly curved surface that curves upward along the inward / outward direction. With this configuration, the tapered extension has a steeper inclination angle at the lower portion of the tapered extension, which is closer to the lid trim. Therefore, when the support claws support the lid trim, the tapered extension's bracing function is improved, effectively suppressing deformation of the lid trim. Meanwhile, the tapered extension has a gentler inclination angle at the upper portion of the tapered extension, which is closer to the lid skirt. Therefore, when the separation claws contact the upper portion of the tapered extension, the tapered extension is less likely to escape inward, and the downward force from the separation claws is effectively applied to the tapered extension. [Effects of the Invention]

[0014] As described above, by providing a wide tapered extension portion and a narrow lid edging portion, and by forming a large number of downward ribs spaced circumferentially on the tapered extension portion, deformation of the lid flange portion in steps 1 and 2 can be suppressed, the bottom lid can be smoothly pulled downward, and the lid can be securely fitted onto the container body in step 3. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a perspective view showing a packaging container in an open state according to an embodiment of the present invention; [Figure 2] FIG. [Figure 3] FIG. [Figure 4] FIG. [Figure 5] Enlarged view of part P in Figure 4. [Figure 6] FIG. [Figure 7] FIG. [Figure 8] 6A and 6B are cross-sectional views showing the lid of the container, where (a) is a cross-sectional view taken along line AA in FIG. 5, and (b) is a cross-sectional view taken along line BB in FIG. 5. [Figure 9]6A and 6B are cross-sectional views showing the lid of the container, where (a) is a cross-sectional view taken along line CC in FIG. 5, and (b) is a cross-sectional view taken along line DD in FIG. 5. [Figure 10] FIG. 2 is an enlarged cross-sectional view of the main part corresponding to line AA showing the container in a closed state. [Figure 11] FIG. 2 is an enlarged cross-sectional view of the main part corresponding to line DD showing the closed state of the container. [Figure 12] FIG. 4 is an enlarged cross-sectional view of a main part showing the state in which the lids of the container are stacked one on top of the other. [Figure 13] FIG. 10 is an enlarged cross-sectional view of the main part showing the state in which the lids are stacked one on top of the other. [Figure 14] FIG. [Figure 15] FIG. 10 is an enlarged cross-sectional view of the main part corresponding to line CC, showing the state during the lid closing operation of the container. DETAILED DESCRIPTION OF THE INVENTION

[0016] A packaging container according to one embodiment of the present invention will be described below with reference to Figures 1 to 15. The container is capable of accommodating various contents, and is particularly suitable for various foods. The container is also suitable for an automatic lid closing machine, more specifically, for an automatic lid closing machine that pulls the bottommost lid downward one by one from a stack of lids.

[0017] As shown in Fig. 1, the container comprises a container body 1 with an opening at the top, and a lid 2 that is placed on top of the container body 1 to close the opening at the top of the container body 1. An inner tray may be provided between the container body 1 and the lid 2.

[0018] The container body 1 and the lid 2 are both made of synthetic resin sheets and are formed by so-called sheet molding. Examples of sheet molding include vacuum forming, pressure forming, vacuum pressure forming, double-sided vacuum forming, and hot plate forming. In any case, they are formed by thermoforming a synthetic resin sheet. The synthetic resin sheet is made of, for example, a styrene-based resin such as polyethylene terephthalate or polystyrene, or an olefin-based resin such as polypropylene or polyethylene. A foamed sheet made by foaming these sheet materials may be used for the container body 1. A non-foamed sheet is preferably used for the lid 2, and a transparent sheet is particularly preferred. Stretched sheets are preferred because they can improve heat resistance and strength while maintaining transparency.

[0019] The shape of the container in plan view may be various, and may be a polygonal shape such as a rectangular shape in plan view, a circular shape, an elliptical shape, etc. The container body 1 and the lid 2 have corresponding shapes in plan view. In this embodiment, they are circular in plan view.

[0020] <Container body 1> As shown in Figures 1 to 3, the container body 1 comprises a circular bottom surface portion 10, a body side surface portion 11 that rises upward while widening outward from the peripheral edge of the bottom surface portion 10, and a body flange portion 12 that extends outward from the upper end of the body side surface portion 11. A convex portion or ridge may be provided on the upper surface of the bottom surface portion 10. Legs may be provided on the peripheral edge of the lower surface of the bottom surface portion 10 that protrude downward. The body side surface portion 11 may be provided with anti-blocking body convex portions 13 to prevent blocking when container bodies 1 are stacked one on top of another.

[0021] The main body flange portion 12 is provided around the entire upper end of the main body side portion 11. Figures 10 and 11 show enlarged views of the main body flange portion 12 and its vicinity of the container body 1. The main body flange portion 12 has a main body flange upper surface portion 14 extending from the main body side portion 11, a main body skirt portion 15 extending from the main body flange upper surface portion 14, and a main body edging portion 16 extending from the main body skirt portion 15. The main body flange upper surface portion 14 may have various shapes, including a beaded shape curved upward, but in this embodiment, it has a flat surface. That is, the main body flange upper surface portion 14 extends approximately horizontally outward from the upper end of the main body side portion 11. The height of the main body flange upper surface portion 14 is constant around the entire circumference, but may vary circumferentially.

[0022] The main body skirt portion 15 extends downward from the outer edge of the main body flange upper surface portion 14. The main body skirt portion 15 includes a main body flange shoulder portion 17 extending from the main body flange upper surface portion 14, a main body engaging protrusion 18 extending from the main body flange shoulder portion 17, a main body skirt reference surface portion 19 extending from the main body engaging protrusion 18, and a skirt lower portion 20 extending from the main body skirt reference surface portion 19. The main body flange shoulder portion 17 extends downward while sloping outward from the outer edge of the main body flange upper surface portion 14. In other words, the main body flange shoulder portion 17 extends downward while expanding in diameter. The main body flange shoulder portion 17 functions as a guide when the lid 2 is externally fitted onto the container body 1, as described below.

[0023] The main body engaging projection 18 is continuous with the underside of the main body flange shoulder 17. The main body engaging projection 18 protrudes outward. The upper surface of the main body engaging projection 18 is located on an extension of the main body flange shoulder 17 and is formed flush with the main body flange shoulder 17. The main body engaging projection 18 is preferably a long circumferential protrusion. The main body engaging projection 18 may be formed along the entire circumference, or may be partially discontinuous at one or several locations along the circumference. The main body skirt reference surface 19 is continuous with the underside of the main body engaging projection 18. The main body skirt reference surface 19 extends downward approximately perpendicularly from the lower end of the main body engaging projection 18. The main body skirt reference surface 19 is located one step inward from the main body engaging projection 18. In other words, the main body engaging projection 18 protrudes outward from the main body skirt reference surface 19.

[0024] The skirt lower portion 20 is continuous with the lower side of the main skirt reference surface portion 19. The skirt lower portion 20 extends downward from the lower end of the main skirt reference surface portion 19 while widening in diameter. The skirt lower portion 20 is connected to the main edging portion 16. In this embodiment, the skirt lower portion 20 has a two-stage configuration. That is, the skirt lower portion 20 has an upper tapered portion 20a and a lower tapered portion 20b. The lower tapered portion 20b is bent downward relative to the upper tapered portion 20a. The inclination angle of the upper tapered portion 20a relative to the horizontal plane is relatively small, while the inclination angle of the lower tapered portion 20b relative to the horizontal plane is relatively large. That is, the upper tapered portion 20a has a gentle slope, and the lower tapered portion 20b has a steep slope. However, the skirt lower portion 20 may have a single-stage tapered configuration.

[0025] The main body edging portion 16 is the portion that forms the outer edge of the container body 1. The main body edging portion 16 extends outward substantially horizontally from the lower end of the main body skirt portion 15. More specifically, the main body edging portion 16 extends outward from the lower end of the skirt lower portion 20. Note that the main body edging portion 16 may be provided with a main body grip portion (not shown).

[0026] <Lid 2> The lid 2 is shown together with the container body 1 in Figures 1 to 3. Details of the lid 2 are shown in Figures 4 to 9. The lid 2 is formed in a shape in plan view that corresponds to the container body 1, and in this embodiment, is circular in plan view. The lid 2 includes a top surface portion 30 that is circular in plan view, a lid side surface portion 31 that extends downward from the peripheral edge of the top surface portion 30, and a lid flange portion 32 that extends outward from the lower end of the lid side surface portion 31.

[0027] The top surface portion 30 has a top surface main portion 30a and a top surface annular portion 30b provided on the outside of the top surface main portion 30a. The top surface main portion is a main portion of the top surface portion 30 and occupies most of the top surface portion 30. The top surface main portion 30a does not have any irregularities such as ribs, and therefore the top surface main portion 30a is a flat, smooth surface without any irregularities. The top surface annular portion 30b is formed one step higher than the top surface main portion 30a; in other words, the top surface main portion 30a is formed one step lower than the top surface annular portion 30b. The top surface annular portion 30b is annular and surrounds the outside of the top surface main portion 30a. The top surface annular portion 30b forms the peripheral portion of the top surface portion 30.

[0028] The lid side surface portion 31 extends downward while widening from the peripheral edge of the top surface portion 30b. Specifically, the lid side surface portion 31 extends downward from the outer edge of the top surface annular portion 30b. It is preferable that the lid side surface portion 31 is formed with a lid protrusion 33 for preventing blocking, which prevents the lids 2 from fitting tightly together and becoming unable to separate when the lids 2 are stacked one on top of the other (blocking phenomenon).

[0029] The lid flange portion 32 corresponds to the main body flange portion 12. The lid flange portion 32 extends outward from the lower end of the lid side surface portion 31 and is formed around the entire periphery. The lid flange portion 32 includes a lid flange upper surface portion 34 extending from the lid side surface portion 31, a lid skirt portion 35 extending from the lid flange upper surface portion 34, a tapered extension portion 36 extending from the lid skirt portion 35, and a lid edging portion 37 extending from the tapered extension portion 36. The lid flange upper surface portion 34 extends approximately horizontally outward from the lower end of the lid side surface portion 31. The lid flange upper surface portion 34 corresponds to the main body flange upper surface portion 14.

[0030] The lid skirt portion 35 extends downward from the outer edge of the lid flange upper surface portion 34 and connects to the tapered extension portion 36. The lid skirt portion 35 includes a lid flange shoulder portion 38 extending from the lid flange upper surface portion 34, a lid skirt reference surface portion 39 extending from the lid flange shoulder portion 38, and an inward engagement protrusion 40 protruding inward relative to the lid skirt reference surface portion 39. The lid flange shoulder portion 38 extends downward from the outer edge of the lid flange upper surface portion 34 while sloping outward. That is, the lid flange shoulder portion 38 extends downward while widening in diameter. The lid flange shoulder portion 38 corresponds to the main flange shoulder portion 17. The inclination angle of the lid flange shoulder portion 38 preferably corresponds to the inclination angle of the main flange shoulder portion 17. The lid flange shoulder portion 38 is formed with an inward-protruding abutment protrusion portion 38a. The abutment protrusion portion 38a may be a circumferentially extending protrusion. The tip of the contact protrusion 38a is preferably sharp.

[0031] The lid skirt reference surface portion 39 is continuous with the underside of the lid flange shoulder portion 38. The lid skirt reference surface portion 39 extends downward substantially vertically from the lower end of the lid flange shoulder portion 38. The lid skirt reference surface portion 39 corresponds to the main body skirt reference surface portion 19. The inward engagement protrusions 40 correspond to the main body engagement protrusions 18. The inward engagement protrusions 40 are provided at the lower end of the lid skirt portion 35. The inward engagement protrusions 40 are preferably circumferentially extending protrusions. Although the inward engagement protrusions 40 may be provided around the entire circumference, in this embodiment, multiple inward engagement protrusions 40 having a predetermined circumferential length are provided at intervals in the circumferential direction. The inward engagement protrusions 40 are arranged at predetermined intervals in the circumferential direction. Therefore, the lower end of the lid skirt portion 35 is divided into a protrusion region 35a where the inward engagement protrusions 40 are provided and a protrusion-free region 35b where the inward engagement protrusions 40 are not provided. Fig. 8 shows the cross-sectional shape of the non-protrusion region 35b, and Fig. 9 shows the cross-sectional shape of the protrusion region 35a. The protrusion region 35a and the non-protrusion region 35b are provided alternately in the circumferential direction around the entire circumference. Note that the circumferential length of the protrusion region 35a (the circumferential length of the inward engaging projections 40) and the circumferential length of the non-protrusion region 35b may be the same or different, but in this embodiment, the circumferential length of the protrusion region 35a is longer than the circumferential length of the non-protrusion region 35b.

[0032] The tapered extension portion 36 extends from the lower end of the lid skirt portion 35. The tapered extension portion 36 extends from the lower end of the lid skirt portion 35 at an angle downward toward the outside. The tapered extension portion 36 may have a shape that is not curved along the inward / outward direction, but in this embodiment, it has an upwardly curved surface that curves upward along the inward / outward direction. As shown in FIG. 8(a), the tapered extension portion 36 extends outward so as to bend from the lower end of the lid skirt reference surface portion 39 in the non-protrusion region 35b. Furthermore, as shown in FIG. 9(a), the tapered extension portion 36 extends outward so as to bend from the lower end of the inward engagement protrusion 40 in the protrusion region 35a. The position of the outer edge of the tapered extension portion 36 in the inward / outward direction is constant around the entire circumference. On the other hand, the inward and outward position of the inner edge of the tapered extension portion 36 is not constant around the entire circumference, and since the tapered extension portion 36 extends from the inward engaging protrusion 40 in the protrusion region 35a, the non-protrusion region 35b is located more outward than the protrusion region 35a.

[0033] 8(a) and 9(a), the outward dimension of the tapered extension 36 relative to the lid skirt reference surface 39 in a plan view is indicated by the symbol W1. The outward dimension W1 of the tapered extension 36 relative to the lid skirt reference surface 39 in a plan view is the dimension in the inward / outward direction from the lid skirt reference surface 39 to the outer edge of the tapered extension 36 in a plan view, and is the dimension of the portion of the tapered extension 36 that protrudes outward from the lid skirt reference surface 39. In the protrusion-free region 35b as shown in FIG. 8(a), the outward dimension W1 of the tapered extension 36 relative to the lid skirt reference surface 39 in a plan view is the total dimension of the tapered extension 36 in the inward / outward direction. 9(a), the outward inward / outward dimension W1 of the tapered extension 36 relative to the lid skirt reference surface 39 in a plan view is not the total inward / outward dimension of the tapered extension 36, but rather the inward / outward dimension of only the portion of the total inward / outward dimension of the tapered extension 36 that is positioned outward from the lid skirt reference surface 39. The tapered extension 36 in the protrusion region 35a extends further inward than the tapered extension 36 in the non-protrusion region 35b.

[0034] As shown by the two-dot chain lines in Figures 8(a) and 9(a) and by the solid lines in Figures 8(b) and 9(b), downward ribs 41 are formed on the tapered extension portion 36. The downward ribs 41 protrude downward. However, the downward ribs 41 do not protrude below the height of the lid trim portion 37, and are positioned above the lid trim portion 37. The downward ribs 41 are formed at regular intervals in the circumferential direction, and a large number of them are formed around the entire circumference of the tapered extension portion 36. Therefore, the downward ribs 41 are formed in the non-protrusion region 35b as shown in Figure 8, and also in the protrusion region 35a as shown in Figure 9.

[0035] The downward rib 41 may have any shape. In this embodiment, the downward rib 41 has a pair of left and right rib side portions 42 and a rib bottom portion 43. The rib side portions 42 extend in the up-down direction and also in the inward-outward direction. The rib side portions 42 are planar and extend in the up-down direction and the inward-outward direction. The rib side portions 42 function as vertical walls. The rib bottom portion 43 connects the lower ends of the left and right rib side portions 42 to each other laterally, i.e., in the circumferential direction. The rib bottom portion 43 has a bent portion 44. The bent portion 44 extends in the circumferential direction and connects the left and right rib side portions 42 to each other. The bent portion 44 is bent so that its upper surface forms a valley fold. Therefore, the rib bottom portion 43 protrudes downward at the bent portion 44. By providing the bent portion 44 in the rib bottom portion 43 in this manner, the rib bottom portion 43 is divided into two regions, an inner region and an outer region, by the bent portion 44. That is, the rib bottom surface portion 43 is divided into an inner bottom surface portion 45 located inside the bent portion 44, and an outer bottom surface portion 46 located outside the bent portion 44. The cross-sectional shapes of the inner bottom surface portion 45 and the outer bottom surface portion 46 are each arbitrary, but in this embodiment, the inner bottom surface portion 45 is flat, and the outer bottom surface portion 46 is a curved surface that curves upward. The inner-outer dimension W3 of the inner bottom surface portion 45 in a plan view is larger than the inner-outer dimension W4 of the outer bottom surface portion 46 in a plan view. In other words, there is a relationship W3 > W4. Note that the outer bottom surface portion 46 may also be flat.

[0036] As shown in Figure 9, in the protrusion-containing region 35a, the rib bottom surface portion 43 is connected to the inward engaging protrusion 40 and also to the inner edge of the tapered extension portion 36. On the other hand, in the protrusion-free region 35b as shown in Figure 8, the downward rib 41 has a rib back surface portion 47. The rib back surface portion 47 is flush with the lid skirt reference surface portion 39 and is an extension portion that extends downward from the lid skirt reference surface portion 39 in a substantially vertical direction.

[0037] The lid trim 37 forms the outer edge of the lid 2 and extends substantially horizontally outward from the lower end and outer edge of the tapered extension 36. The inner-outer dimension W2 of the lid trim 37 in a plan view is smaller than the inner-outer dimension W1 of the tapered extension 36 relative to the lid skirt reference surface 39 in a plan view. In other words, the relationship W1 > W2 is satisfied. A lid grip 48 may be provided at a predetermined location along the entire circumference of the lid trim 37. The lid grip 48 may be provided in one location or multiple locations.

[0038] At least the outer periphery of the main body edging 16 and the lid edging 37 may be provided with a number of very fine irregularities to reinforce the surface and prevent fingers from being cut when they come into contact with the surface. These irregularities are wavy when viewed enlarged from the front, with numerous peaks and valleys extending in the width direction along each side and extending radially in the plan view along the corners. The irregularities may be formed by knurling, such as flat knurling or twill knurling, and preferably by twill knurling to prevent slippage.

[0039] <Lid closed> Figures 3, 10, and 11 show the closed state of the container. The lid 2 is fitted onto the container body 1. The lid flange upper surface 34 faces the upper side of the body flange upper surface 14. The lid flange upper surface 34 preferably faces the body flange upper surface 14 with a gap therebetween, but may also be in contact. The lid skirt 35 is located outside the body skirt 15. The lid flange shoulder 38 faces the body flange shoulder 17, and the abutting protrusion 38a abuts against the body flange shoulder 17. The abutting protrusion 38a abuts against the body flange shoulder 17, determining the height of the lid 2 relative to the container body 1. Furthermore, the abutting protrusion 38a makes line contact with the body flange shoulder 17 along the circumferential direction.

[0040] The inward engagement protrusion 40 of the lid 2 engages with the main body engagement protrusion 18. The inward engagement protrusion 40 is located below the main body engagement protrusion 18. The lid skirt reference surface portion 39 faces the outside of the main body skirt reference surface portion 19. The main body engagement protrusion 18 abuts against the inner surface of the lid skirt reference surface portion 39, but may face it across a gap. The inward engagement protrusion 40 abuts against the outer surface of the main body skirt reference surface portion 19, but may face it across a gap. The tapered extension portion 36 and the downward rib 41 face each other at a distance on the outside of the skirt lower portion 20. The lid edge portion 37 is located above and away from the main body edge portion 16. The lid edge portion 37 is located outward of the main body edge portion 16.

[0041] <2 lids stacked together> 12 and 13 show a stacking state in which the lids 2 are stacked one on top of the other. Note that, for the sake of explanation, FIG. 13 shows only two lids 2 stacked on top of each other. The top surface 30 of the upper lid 2 does not abut the top surface 30 of the lower lid 2, but is positioned facing the upper side with a predetermined gap. The downward rib 41 of the upper lid 2 abuts the lid flange shoulder 38 of the lower lid 2. More specifically, the rib bottom surface 43 of the downward rib 41 provided in the protruding region 35a abuts the lid flange shoulder 38. In particular, the inner bottom surface 45 of the rib bottom surface 43 abuts the lid flange shoulder 38. The rib bottom surface 43 abuts the outer portion of the lid flange shoulder 38. Specifically, the rib bottom surface 43 abuts the portion of the lid flange shoulder 38 that is outer than the abutment protrusion 38a. In this way, the downward ribs 41 of the upper lid 2 abut against the lower lid 2, resulting in a stable stacked state. In particular, the downward ribs 41 in the protruding region 35a abut against the lower lid 2. Therefore, the inward engaging protrusions 40 also have an added strength-enhancing effect, resulting in a highly stable stacked state. Furthermore, the rib bottom portions 43 of the downward ribs 41 in the protruding region 35a are connected to and continuous with the inward engaging protrusions 40. Therefore, the composite structure of the downward ribs 41 and the inward engaging protrusions 40 ensures high strength at the abutting portions, ensuring a stable stacked state. Furthermore, the rib bottom portions 43 of the upper lid 2 abut against the lid flange shoulder portions 38 of the lower lid 2, making it difficult for the lids 2 to block against each other. Therefore, the bottom lid 2 can be easily separated downward in the separating process using the separating claws, which will be described later.

[0042] <Automatic lid closing process> The stacked assembly of lids 2 is transferred to an automatic lid closing machine. The automatic lid closing machine is equipped with support claws 100 that support the stacked lids 2 from below and separation claws 110 that separate and drop the bottom lid 2. The support claws 100 reciprocate horizontally, moving inward and outward along the lids 2. The stacked lids 2 are supported by the support claws 100. For example, two support claws 100 are arranged 180 degrees apart on both sides of the lid 2. As shown in Figure 14, the support claws 100 are positioned below the lid edge 37 of the bottom lid 2 and abut against the underside of the lid edge 37 to support the lid 2. The lid edge 37 is supported by the support claws 100, but the lid edge 37 has a smaller dimension in the inward and outward directions than the tapered extension 36. The tapered extension 36 supports the lid edge 37 supported by the support claws 100 from the inside. That is, the tapered extension 36 supports the lid trim 37 by tensioning it from diagonally above. Therefore, the lid trim 37 supported by the support claws 100 is less likely to deform. Moreover, because the tapered extension 36 has an upwardly curved surface that curves upward along the inward / outward direction, the inclination angle near the outer edge of the tapered extension 36 is large. Therefore, the tensioning function of the tapered extension 36 is further enhanced.

[0043] Furthermore, since the downward rib 41 is formed on the tapered extension portion 36, the strength of the tapered extension portion 36 itself is increased. As a result, deformation of the tapered extension portion 36 itself is suppressed, the support state by the support claws 100 is further stabilized, and deformation of the lid edging portion 37 is further suppressed. In particular, since the rib side surface portion 42 of the downward rib 41 is aligned along the vertical direction, the rib side surface portion 42 functions as a vertical wall that supports the tapered extension portion 36 in the vertical direction and can firmly absorb the upward force acting from the support claws 100. In addition, since the bent portion 44 is provided on the rib bottom surface portion 43, the strength of the downward rib 41 itself is increased. Furthermore, since the bent portion 44 connects the left and right rib side surface portions 42 to each other, the strength of the downward rib 41 is further increased, and the strength of the tapered extension portion 36 is also further increased.

[0044] The support claws 100 move outward from the state shown in Figure 14 and away from the lid edge portion 37, allowing the bottom lid 2 to fall. Meanwhile, separation claws 110 are arranged on the upper side of the tapered extension portion 36 to pull the bottom lid 2 downward. The separation claws 110 move back and forth in the up and down direction as well as inward and outward. As the support claws 100 move outward, the separation claws 110 move downward. Thereafter, the separation claws 110 move outward to retract, and when the next lid 2 is supported by the support claws 100, they move inward and position themselves above the next lid 2.

[0045] As shown in FIG. 14 , the separation claw 110 contacts the upper surface of the tapered extension 36 and pushes the tapered extension 36 downward. The separation claw 110 contacts the tapered extension 36 near its inner edge. Because the tapered extension 36 is inclined diagonally downward toward the outside, the tapered extension 36 attempts to move inward, but the lid edging 37 prevents the tapered extension 36 from deforming inward. Therefore, the downward force of the separation claw 110 is reliably applied to the tapered extension 36, causing the bottom lid 2 to be pulled downward. Furthermore, because the tapered extension 36 has the downward rib 41, even if the downward force of the separation claw 110 acts on the tapered extension 36, the tapered extension 36 is prevented from deforming, and the downward force of the separation claw 110 can be reliably received. Furthermore, when the tapered extension 36 has an upwardly curved surface, the angle of inclination relative to the horizontal plane near the inner edge of the tapered extension 36 becomes small. Therefore, the downward force of the separation claws 110 can be efficiently applied to the tapered extension 36. Although not shown, the separation claws 110 can also support the second-lowest lid 2. In this case, the support claws 100 supporting the lid edge 37 of the bottom lid 2 move outward, and at the same time, the separation claws 110 move inward to support the second-lowest lid 2. In other words, the two upper and lower claws move inward and outward alternately, allowing the lid 2 to fall and be separated by its own weight.

[0046] The bottom lid 2, pulled downward by the separating claws 110, falls onto, for example, a belt conveyor located below. The belt conveyor then transports the lid 2 downstream. At a downstream suction point, the vacuum of the automatic lid closing machine suctions the top surface 30, particularly the main top surface portion 30a, of the lid 2 on the belt conveyor, lifting the lid 2 and fitting it onto the container body 1 that has been transported separately.

[0047] FIG. 15 shows the lid 2 being fitted onto the container body 1. The inward engagement projections 40 of the lid 2 come into contact with the body flange shoulder 17. Because the body flange shoulder 17 has an inclined surface, the inward engagement projections 40 slide down the inclined surface and move outward while contacting the body flange shoulder 17. That is, the lid skirt 35 expands outward along the body flange shoulder 17, allowing the inward engagement projections 40 to easily climb over the body engaging projections 18 and move below them. In this way, the body flange shoulder 17 functions as a guide when the inward engagement projections 40 climb over the body engaging projections 18 to fit the lid 2 onto the container body 1. This allows the lid 2 to be smoothly fitted onto the container body 1 using an automatic lid-closing machine.

[0048] In this embodiment, the container body 1 is provided with the body engaging protrusions 18, and in the closed state, the inward engaging protrusions 40 of the lid 2 engage with the body engaging protrusions 18. However, the container body 1 does not necessarily have to be provided with the body skirt portion 14 and the body engaging protrusions 18. For example, in the closed state, the inward engaging protrusions 40 may engage with the body edging portion 16. [Explanation of symbols]

[0049] 1 Container body 2 lid 10 Bottom part 11 Side of the main body 12 Body flange 13 Main body protrusion 14 Main body flange upper surface 15 Main body skirt 16 Body edge 17 Body flange shoulder 18 Main body engagement protrusion 19 Body skirt reference surface 20 Lower Skirt 20a Upper tapered section 20b Lower tapered section 30 Top section 30a Main part of the top surface 30b Top annular part 31 Lid side part 32 Lid flange 33 Lid protrusion 34 Top surface of lid flange 35 Lid skirt 35a ridge area 35b Non-protrusion area 36 Tapered extension 37 Lid edge 38 Lid flange shoulder 38a Contact protrusion 39 Lid skirt reference surface 40 Inward engagement protrusion 41 Downward Rib 42 Rib side 43 Rib bottom 44 Bend 45 Inner bottom part 46 Outer bottom part 47 Rib back 48 Lid knob 100 support claws 110 Isolated Claw

Claims

1. A packaging container comprising a container body having a body flange portion and a lid having a lid flange portion that fits externally onto the body flange portion when the lid is closed, the lid flange portion includes a lid skirt portion, a tapered extension portion extending diagonally downward and outward from the lid skirt portion, and a lid edging portion extending substantially horizontally and outward from the tapered extension portion; The lid skirt portion includes a lid skirt reference surface portion extending substantially vertically downward, and an inward engaging protrusion protruding inward from the lid skirt reference surface portion and engaging with the main body flange portion when the lid is closed, The dimension of the tapered extension portion in the inward / outward direction relative to the lid skirt reference surface portion in a plan view is greater than the dimension of the lid edging portion in the inward / outward direction in a plan view; The tapered extension portion is provided with a number of downward ribs that protrude downward and are spaced apart in the circumferential direction around the entire circumference of the tapered extension portion, A packaging container, wherein the downward rib has a bent portion in which the upper surface is bent in a valley fold.

2. The downward rib includes a rib bottom portion and a pair of left and right rib side portions extending in the up-down direction, 2. The packaging container according to claim 1, wherein the bent portion is provided on the bottom surface of the rib and connects the left and right side surface portions of the rib to each other.

3. 3. The packaging container according to claim 1, wherein the tapered extension is an upwardly curved surface that curves upward along the inward-outward direction.

Images