lunch box
The lunch box with a minimal part count and drainage features addresses high manufacturing costs and sticky rice issues by effectively draining moisture, ensuring fluffy rice texture and freshness.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- YAMAZAKI JITSUGYO
- Filing Date
- 2024-11-21
- Publication Date
- 2026-06-02
AI Technical Summary
Existing lunch boxes with multiple parts face high manufacturing costs and risk of rice becoming sticky due to excess moisture during thawing, especially when frozen rice is thawed.
A lunch box design with a minimum number of parts featuring a lunch box body, lid, and inner container with drainage holes and gaps to prevent moisture accumulation, allowing excess moisture to escape, thus preventing rice from becoming sticky.
The design maintains a low manufacturing cost while ensuring fluffy rice texture by effectively draining excess moisture during thawing, keeping rice non-sticky and maintaining freshness.
Smart Images
Figure 2026089998000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a lunch box, and more particularly to a lunch box provided with an inner container for containing rice.
Background Art
[0002] As a lunch box, there is one that separately houses rice and all or part of the side dishes (see, for example, Patent Documents 1 and 2).
[0003] In the lunch box of Patent Document 1, a container storage body 2 is placed on a rice container body 3 for containing rice, and a plurality of inner container bodies 1a containing side dishes are stored in the container storage body 2. With the upper surface opening of the container storage body 2 closed by an outer lid body 4, the container storage body 2 and the rice container body 3 are stacked and joined by a coupling member 5 provided on the outer lid body 4 to form the shape of a lunch box (see FIGS. 2-3 of Patent Document 1).
[0004] In the lunch box of Patent Document 1, after putting side dishes in the inner container body 1a, it is refrigerated or frozen with an inner lid body 1b attached to the opening of the inner container body 1a, and when used, it is thawed by a microwave oven. When forming the lunch box, the inner lid body 1b is removed.
[0005] In the lunch box of Patent Document 1, various side dishes can be stored in a plurality of lidded inner containers 1 composed of the inner container body 1a and the inner lid body 1b, and the side dishes stored with the inner lid body 1b removed can be stored in the container storage body 2 as they are in the inner container body 1a.
[0006] The lunch box of Patent Document 2 stores part of the side dishes in a small container 2 with a lid and stores them in the lunch box 1, and stores the remaining side dishes and rice in the lunch box 1 outside the small container 2 (see FIG. 4 of Patent Document 2). The small container 2 consists of a cup-shaped container body 3 and a lid body 4 covering the container body 3, and a plurality of small protrusions 5 provided on the lid body 4 ensure the air permeability between the inside and outside of the small container 2.
[0007] In the lunch box described in Patent Document 2, when the entire lunch box is heated in a microwave oven, the breathability of the small container 2 prevents heat from accumulating inside the small container 2. [Prior art documents] [Patent Documents]
[0008] [Patent Document 1] Registered Utility Model No. 3135618 Gazette [Patent Document 2] Registered Utility Model No. 3220085 Gazette [Overview of the project] [Problems that the invention aims to solve]
[0009] The lunchbox described in Patent Document 1 has a minimum configuration of 7 parts (see, for example, Figure 1 of Patent Document 1) with 2 inner containers with lids, and has the problem of high manufacturing costs due to the large number of parts. In contrast, the lunchbox described in Patent Document 2 has a minimum configuration of 4 parts, with a lid added to Figure 4 of Patent Document 2, and does not have high manufacturing costs due to the small number of parts.
[0010] On the other hand, in the lunch box of Patent Document 1, it is conceivable that a lid be attached to the rice container 3 in the same way as the inner container 1a, so that the rice contained inside can be refrigerated or frozen. However, when the frozen rice in the rice container 3 is thawed, there is a risk that the rice will become sticky due to the excess moisture generated during thawing.
[0011] On the other hand, the small container 2 in the lunch box described in Patent Document 2 has a lid but is breathable, and is therefore not intended for refrigeration or freezing. However, if rice is frozen in a small container that is airtight, different from the small container 2, and the frozen rice is thawed in that container, the excess moisture generated during thawing may cause the thawed rice to become sticky.
[0012] The present invention aims to provide a lunch box that prevents rice from becoming sticky after thawing, without increasing the number of parts. [Means for solving the problem]
[0013] A lunch box according to a first aspect of the present invention is a lunch box comprising a lunch box body, a lunch box lid, and a lunch box inner container. The lunch box inner container is for holding rice. The bottom plate of the lunch box inner container has a plurality of slits or small holes which are drainage holes. When the lunch box body is placed on a horizontal surface and the lunch box inner container is placed inside the lunch box body, there is a vertical gap between the upper surface of the bottom plate of the lunch box body and the lower surface of the bottom plate of the lunch box inner container.
[0014] A lunch box according to a second aspect of the present invention is a lunch box according to a first aspect, wherein the side plate of the lunch box inner container has a plurality of slits or small holes which are water drainage outlets. When the lunch box body is placed on a horizontal surface and the lunch box inner container is housed inside the lunch box body, there is a horizontal gap between the inner surface of the side plate of the lunch box body and the outer surface of the side plate of the lunch box inner container.
[0015] A lunch box according to a third aspect of the present invention is a lunch box according to a first or second aspect, wherein, when the lunch box inner container is housed within the lunch box body, a liquid-impermeable partition is provided between the storage portion of the lunch box body other than the lunch box inner container and the lunch box inner container.
[0016] A lunch box according to the fourth aspect of the present invention is a lunch box according to the first or second aspect, wherein the lunch box inner container is a colander, and the inner container of a frozen rice container is a frozen rice container comprising a frozen rice container body, a frozen rice container lid, and a frozen rice container inner container.
[0017] In this invention, "rice" refers to cooked rice, not a meal. [Effects of the Invention]
[0018] According to the lunch box of the present invention, in the configuration of the lunch box with the minimum number of parts, there are only the lunch box body, the lunch box lid, and the inner container of the lunch box for accommodating rice. In a more preferred embodiment, it only further includes a partition body. Therefore, since the number of parts does not increase, the manufacturing cost does not increase.
[0019] According to the lunch box of the present invention, on the bottom plate of the inner container of the lunch box, there are moisture discharge ports which are a plurality of slits or small holes. In a state where the lunch box body is placed on a horizontal plane and the inner container of the lunch box is accommodated in the lunch box body, there is a vertical gap between the upper surface of the bottom plate of the lunch box body and the lower surface of the bottom plate of the inner container of the lunch box. Therefore, the surplus moisture generated when thawing the frozen rice accommodated in the inner container of the lunch box enters the gap through the moisture discharge ports on the bottom plate of the inner container of the lunch box and accumulates on the bottom plate of the lunch box body. Therefore, it is possible to prevent the thawed rice accommodated in the inner container of the lunch box from becoming sticky.
Brief Description of the Drawings
[0020] [Figure 1] It is a perspective view showing the lunch box according to an embodiment of the present invention. [Figure 2] It is an exploded perspective view of the lunch box. [Figure 3] It is an exploded perspective view showing a state where the inner container of the lunch box is accommodated in the lunch box body and the lunch box lid is removed. [Figure 4] It is a front view of a longitudinal section of the lunch box. [Figure 5] It is a side view of a longitudinal section of the lunch box. [Figure 6] It is a side view of a longitudinal section showing a state where the lunch boxes are stacked. [Figure 7] It is a perspective view of the frozen rice container. [Figure 8] It is an exploded perspective view of the frozen rice container.
Embodiments for Carrying Out the Invention
[0021] Hereinafter, embodiments according to the present invention will be described based on the drawings. Illustrations of the rice and side dishes placed in the lunch box are omitted.
[0022] The vertical direction is defined when the lunch box according to an embodiment of the present invention is placed on a horizontal plane. In the lunch box, which is substantially rectangular in plan view, the front view is a view of the lunch box placed on a horizontal plane, with the longer side viewed from the side.
[0023] As shown in Figure 1-5, the lunch box 1 according to an embodiment of the present invention comprises a main body 2, a lid 3, an inner container 4, and a divider 9, with the inner container 4 being for holding rice. In this embodiment, the inner container 4 is also the inner container D, which is a strainer in the frozen rice container A (Figure 7-8) described later. The lunch box 1 consists of a main body 2, a lid 3, an inner container 4, and a divider 9, and because it has a small number of parts, the manufacturing cost is not high.
[0024] The main body 2 is a container with an opening at the top, consisting of a bottom plate 5 which is roughly rectangular in plan view, opposing side plates 7A, 7A which rise from the long edge of the bottom plate 5, and opposing side plates 7B, 7B which rise from the short edge of the bottom plate 5.
[0025] The lid 3 closes the top opening of the main body 2 and is equipped with a sealing valve 10 and a gasket 11. By pressing down the sealing valve 10, the lunch box 1 can be sealed, preventing the rice and side dishes from drying out, keeping them fresh for longer, and making it less likely for liquids to leak. When heating in a microwave oven, lift the sealing valve 10 to allow air to circulate inside and outside the lunch box 1.
[0026] As shown in Figure 2, the inner container 4 consists of a bottom plate 6 that is roughly square in plan view, and opposing side plates 8A, 8A and opposing side plates 8B, 8B that rise from the edge of the bottom plate 6, and can hold, for example, about 130-170g of rice, which is about one bowlful.
[0027] The bottom plate 6 of the inner container 4 has multiple slits S, which are water drainage openings H1. The water drainage openings H1 may also be multiple small holes. The side plates 8A and 8B of the inner container 4 have multiple slits S, which are water drainage openings H2. The water drainage openings H2 may also be multiple small holes.
[0028] As shown in Figure 3-5, the lower surface of the flange F at the upper end of the inner container 4 contacts the stepped portion 2A of the main body 2. Therefore, as shown in Figure 4-5, when the inner container 4 is housed inside the main body 2, it is suspended in mid-air, and there is a vertical gap G1 between the upper surface of the bottom plate 5 of the main body 2 and the lower surface of the bottom plate 6 of the inner container 4.
[0029] Therefore, excess moisture generated when thawing the frozen rice stored in the inner container 4 enters the gap G1 through the moisture drain H1 on the bottom plate 6 of the inner container 4 and accumulates on the bottom plate 5 of the main body 2. Thus, it is possible to prevent the thawed rice stored in the inner container 4 from becoming sticky.
[0030] In addition to the vertical gap G1 mentioned above, as shown in Figure 4, there is a horizontal gap G2 between the inner surface of the side plate 7B of the main body 2 and the outer surface of the side plate 8B of the inner container 4, and as shown in Figure 5, there is a horizontal gap G2 between the inner surface of the side plate 7A of the main body 2 and the outer surface of the side plate 8A of the inner container 4.
[0031] Therefore, when thawing the frozen rice stored in the inner container 4, steam circulates through the moisture outlet H1 in the bottom plate 6 of the inner container 4, the vertical gap G1, the horizontal gap G2, and the moisture outlet H2 in the side plates 8A and 8B of the inner container 4. As a result, the rice in the inner container 4 can be cooked until fluffy, resulting in a fluffy texture after thawing.
[0032] As shown in Figure 3-4, the partition 9 separates the inner container 4 from the storage section E within the main body 2, when the inner container 4 is housed inside the main body 2. The partition 9 is a component formed to fit the upper surface of the bottom plate 5 of the main body 2 and the inner surfaces of the side plates 7A, 7A of the main body 2, preventing liquid from passing through. Therefore, the moisture from the rice in the inner container 4 does not mix with the side dishes in storage section E, and the moisture and seasonings from the side dishes in storage section E do not mix with the rice in the inner container 4.
[0033] In this embodiment, the partition 9 is a separate component from the main body 2 that can be attached to and detached from the main body 2, as shown in Figures 2 and 4, but it may also be formed integrally with the main body 2.
[0034] The lunch box 1 of this embodiment is compatible with refrigerators, microwave ovens, and dishwashers. The sealing valve 10 and gasket 11 of the lid 3 are made of, for example, silicone rubber, while the rest of the box is made of, for example, polypropylene.
[0035] When washing lunch box 1 in a dishwasher, disassemble the lunch box 1 and place the main body 2, lid 3, inner container 4, and divider 9 into the dishwasher basket. This allows the parts of lunch box 1 to be washed separately in the dishwasher, keeping them clean. Therefore, maintenance of frequently used lunch box 1 becomes very easy.
[0036] As shown in Figure 4-5, the lunch box 1 has a protrusion 2B on the bottom surface of the main body 2, and as shown in Figures 1 and 4-5, there is a recess 3A on the top surface of the lid 3. When stacked as shown in Figure 6, the protrusion 2B of the upper lunch box 1 fits into the recess 3A of the lower lunch box. Therefore, when stacked as shown in Figure 6, the upper and lower lunch boxes 1,1 are unlikely to shift horizontally, so they can be neatly stored, for example, in a refrigerator.
[0037] The frozen rice container A shown in Figure 7-8 consists of a main body B, a lid C, and an inner container D which is a strainer. For example, freshly cooked rice is placed in the inner container D inside the main body B, and the lid D is fitted onto the main body B to seal it and freeze it. When eating the rice, the entire frozen rice container A is placed in a microwave oven and the frozen rice is defrosted in the microwave.
[0038] In the lunch box 1 of this embodiment, for example, the inner container 4 shown in Figure 2 is the same as the inner container D of the frozen rice container A shown in Figure 8. Therefore, after thawing the rice frozen in the frozen rice container A, the fluffy rice, along with the inner container D which is a sieve, can be placed inside the main body 2 of the lunch box 1 as shown in Figure 3.
[0039] Then, when side dishes are placed in the storage compartment E other than container 4 inside the main body 2 in Figure 3, a bento box with side dishes and fluffy rice is completed. Even if the bento box 1 cools down over time, it can be heated in a microwave oven with the sealing valve 10 shown in Figures 1 and 4 raised. During heating, excess moisture released from the rice passes through the moisture outlet H1 in the bottom plate 6 of the inner container D (inner container 4), which is a sieve, into the gap G1 and accumulates on the bottom plate 5 of the main body 2.
[0040] The embodiments described above are all illustrative and not limiting. Various improvements and modifications can be made without departing from the scope of the present invention. [Explanation of symbols]
[0041] 1 lunch box 2 Main unit 2A stepped section 2B protrusion 3 Lid 3A Recess 4 Inner container 5,6 Bottom plate 7A,7B,8A,8B side plate 9 partitions 10 Sealed valve 11 Gasket A Frozen rice container B Main Unit C Lid body D. Colander (inner container) E. Storage compartments other than the inner container F flange section G1 Vertical gap G2 Horizontal gap H1,H2 Moisture drain port S-slit
Claims
1. A lunch box comprising a lunch box body, a lunch box lid, and a lunch box inner container, The inner container of the lunch box is for holding rice, The bottom plate of the inner container of the lunch box has multiple slits or small holes which are drainage openings for moisture. With the lunch box body placed on a horizontal surface and the lunch box inner container placed inside the lunch box body, there is a vertical gap between the upper surface of the bottom plate of the lunch box body and the lower surface of the bottom plate of the lunch box inner container. lunch box.
2. The side panel of the inner container of the lunch box has multiple slits or small holes which are drainage openings. With the lunch box body placed on a horizontal surface and the lunch box inner container placed inside the lunch box body, there is a horizontal gap between the inner surface of the side plate of the lunch box body and the outer surface of the side plate of the lunch box inner container. The lunch box according to claim 1.
3. With the lunch box inner container housed within the lunch box body, a liquid-impermeable partition is provided between the storage area within the lunch box body other than the lunch box inner container and the lunch box inner container. The lunch box according to claim 1 or 2.
4. The inner container of the lunch box is, It's a sieve, A frozen rice container comprising a frozen rice container body, a frozen rice container lid, and a frozen rice container inner container, wherein the frozen rice container inner container is The lunch box according to claim 1 or 2.