JPH0139764B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a lunch container made of synthetic resin and having a double hollow structure of inner and outer casings. This makes it possible to provide a lunch container that is lightweight in structure and has excellent strength.

To this end, the present invention has a downward facing edge on the outside of the rising periphery of the inner housing, and
This downward edge has an L-shaped step on the inside of the lower end,
Furthermore, an inner casing having a rib provided with an L-shaped step integral with the L-shaped step on the outer side of the lower end at an appropriate interval between the peripheral edge and the downward edge, and a rising periphery of the outer casing plate. An outer casing having a downwardly slanted protrusion, an undulating part connected to the protrusion, and an L-shaped stepped part on the outside of the part are molded separately from a synthetic resin material, and then the L-shaped part of the downwardly facing edge of the inner casing is molded separately. The L-shaped stepped part and the upper end of the rising edge of the outer casing are engaged with the L-shaped stepped part of the rib, and the interval between the rising edge and the downward edge and the interval between the inner and outer casings are maintained constant. The engaging portions of the inner and outer casings are integrally heat-sealed to form a double hollow casing structure, and then the L-shaped stepped portion of the outer casing is connected from the lower end of the downward edge of the inner casing to the inner and outer casings. A bento container is obtained by integrally molding a band-shaped part made of a synthetic resin material over the entire outer edge of the rising peripheral part thereof and thermally fused with the diagonal protrusions and the undulating part. It is.

Hereinafter, the present invention will be explained with reference to the drawings.

Fig. 1 is a plan view of an example of a bento container obtained by the present invention, Fig. 2 is a cross-sectional view taken along the line ``-'', and Figs. 3 to 6 are partially omitted to show the manufacturing process thereof. In the method of the present invention, first, the inner casing 1 and the outer casing 10 are separately molded using synthetic resin materials such as A, B, and S resins.

The inner casing 1 has an inner casing plate 2 as shown in FIG.
It has a downward facing edge 4 on the outside of the rising peripheral edge 3, and has an L-shaped step 5 on the inside of this edge 4, and there is an appropriate interval between the peripheral edge 3 and the edge 4. , has a rib 6 with an L-shaped step 7 connected to the step 5 of the edge 4 on the outer side of the lower end.

This rib 6 maintains a constant distance between the rising peripheral edge 3 and the downward edge 4 of the inner casing 1 during molding of the outer casing 10 and the band-shaped portion, which will be described later. It functions to maintain.

As shown in FIG. 4, the outer casing 10 has a downwardly slanted protrusion 13 on the outside of the rising peripheral edge 12 of the outer casing plate 11, and also has an undulating portion 14 connected to this protrusion 13, Furthermore, there is an L-shaped stepped portion 15 at the border with the flat portion of the outer housing plate.

Note that the inner casing 1 is of course not limited to the shape having a number of side food casings 8 shown in FIGS. 1 and 2; and this edge 4
The shape of the inner housing plate 2 is arbitrary as long as it has an L-shaped stepped portion 5 on the inside thereof, and further has ribs 6 integrally formed between the peripheral edge portion 3 and the edge portion 4.

As shown in FIG.
With the upper end of the rising peripheral edge 12 of the outer casing 10 engaged with the L-shaped stepped portion 5 of the inner casing 1 and the L-shaped stepped portion 7 of the rib 6, the engaging portions of both are tightened with a mold. Heat to fuse them together.

In this case, since the distance between the rising edge 3 and the edge 4 of the inner housing 1 is maintained by the ribs 6, the space between the edge 3 and the edge 4 will not be crushed during molding.

In this way, the inner and outer casings 1 and 10 are formed,
A double hollow casing structure is formed, and then, as shown in FIG. Band-shaped part 20 made of resin material
are integrally molded to obtain the lunch container illustrated in FIGS. 1 and 2.

In this case, the joints of the inner and outer casings 1 and 10 are integrally heat-sealed, and the distance between the inner and outer casings 1 and 10 is maintained by ribs 6 provided at appropriate intervals. Therefore, there is no possibility that the material will enter the hollow A between the inner and outer casings 1 and 10 during molding. The inner and outer casings 1, 10 and the band-shaped part 20 are bonded together extremely strongly due to the synergistic action of the parts.

In addition, for the lid body, a known molding method is used.
In addition, since any known structure may be used, illustration and description thereof will be omitted.

According to the present invention, the material does not enter the hollow space between the inner and outer casings during molding, so there is no wastage of material, making it possible to manufacture the lunch box at low cost, and making it lightweight and robust. It is possible to obtain a container.

In other words, the lunch container obtained by the present invention has a double hollow casing structure with an inner and outer casing, and the inner and outer casings and the strip are bonded integrally and strongly, so that it has a high strength. Not only is it excellent, but it also has the best shock absorption effect, which prevents damage to the lunch container itself.Furthermore, since no material enters the hollow space between the inner and outer casings during molding, it is lightweight. Not only is it easy to handle, but there is no wastage of materials and it can be provided at a low cost.

[Brief explanation of drawings]

Fig. 1 is a plan view of a lunch container obtained by the present invention, Fig. 2 is a sectional view taken along the line - ditto above, and Figs. 3 to 6 are partially omitted showing the manufacturing process according to the present invention. Fig. 3 shows the inner casing, Fig. 4 shows the outer casing, Fig. 5 shows the molded state of the inner and outer casings, and Fig. 6 shows the final state after forming the strip. shows. DESCRIPTION OF SYMBOLS 1... Inner housing, 2... Inner housing plate, 3... Rising peripheral edge, 4... Downward edge, 5... L-shaped step, 6... Rib, 10... Outer housing, 11... ...outer housing plate, 12...rising peripheral edge portion, 13...downward diagonal projection, 20...band-shaped portion.

Claims (1)

[Claims] 1 has a downward edge 4 on the outside of the rising peripheral edge 3 of the inner casing plate 2, has an L-shaped step 5 on the inside of the lower end of this downward edge 4, and furthermore has the above peripheral edge 3 and the downward edge 4 An inner casing 1 having a rib 6 having an L-shaped step 7 integral with the L-shaped step 5 on the outer side of the lower end, and a rising peripheral edge 12 of an outer casing plate 11 at an appropriate interval between them. A downwardly diagonal protrusion 13 on the outside, an undulating portion 14 connected to the protrusion 13, and an L-shaped stepped portion 1
5 and an outer casing 10 are molded separately from synthetic resin material, and then the L-shaped step 5 of the downward edge 4 of the inner casing 1 and the L-shaped step 7 of the rib 6 are molded separately from the outer casing. The upper end of the rising peripheral edge 12 of the body 10 is engaged with the rising peripheral edge 3 and the downward facing edge 4.
The engaging portions of the inner and outer casings 1 and 10 are integrally heat-sealed with the distance between the inner and outer casings 1 and 10 kept constant, and the two of the inner and outer casings 1 and 10 are It has a heavy hollow casing configuration, and then extends over the entire outer edge of the rising peripheral edge 12 from the lower end of the downward edge 4 of the inner casing 1 to the L-shaped stepped portion 15 of the outer casing 10, and its diagonal protrusions 13 and A method for manufacturing a lunch container, characterized in that the lunch container is obtained by integrally molding a belt-shaped part 20 made of a synthetic resin material with heat fusion bonding with the undulating part 14.