JPH0423767Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a hollow double-walled container made of blow-molded thermoplastic plastic for storing various articles such as typewriters, musical instruments, and tools.

Prior art The hollow double-walled container mentioned above was manufactured by the Special Publication Publication No. 49-18748.
The one shown in the publication is widely known.

The above-mentioned known hollow double-walled container is constructed as shown in FIGS. 4 and 5, and the main body a and the lid body b are connected by an integrally molded thin hinge c,
A latch e is provided on the side edge of the lid b via a thin hinge d, and a locking protrusion f for locking the latch e is provided on the main body a side.

Problems to be Solved by the Invention The above-mentioned conventional hollow double-walled container is composed of the mating surfaces of the container, which are pinch-off parts during blow molding, and in particular, the parison is compressed and joined during blow molding, as shown in Figure 4. Thin strip-like lines g due to folded meat were generated at the protruding portion of the hinge d connecting the latch e, which sometimes spoiled the appearance of the container.

The reason why the above-mentioned streak-like line g is generated is that during the molding of the container shown in FIG. It is thought that this is because the accumulated resin of the parison j located in the part moves to the other cavity side because there is a compression cavity for molding the latch e on one side, and this rubs against the inner surface of the cavity k. The above-mentioned phenomenon occurs more significantly in a narrow container between two hollow double walls, especially when the width of the hinge d in the bending direction is wide.

Means and Effects for Solving the Problems The present invention was developed in consideration of the above-mentioned problems, and even if the resin that was accumulated when the hinge part was molded moves toward the cavity side, it will not move along the inner surface of the cavity. The object of the present invention is to provide a hollow double-walled container which is prevented from moving and which prevents streak-like lines from being formed on the surface of the container at the hinge protrusion. On one mating surface of the lid, on the outside of the mating surface on the protruding side of the hinge, a protrusion with a width A that fits into the recessed part of the other mating surface is provided, and the width A of this protrusion and the hinge The dimensional relationship between the width B in the bending direction and the average wall thickness t of the container is 0.5B<A>2.2t. The resin that has moved toward the cavity side of the container is held within the cavity of the protrusion, and is prevented from moving along the surface of the cavity of the container.

Embodiment An embodiment of the present invention will be described based on FIGS. 1 to 3.

In this embodiment, the protruding portion of the latch will be explained.

In the figure, 1 is the main body, and 2 is the lid. The main body 1 and the lid 2 are connected together by a compressed and thinned hinge 3, and a concave cavity and a convex cavity extend from the parison, respectively. It has a hollow double wall structure with the inner and outer walls integrated during blow molding.

4 is a latch integrally provided via a hinge 5 located at the outer edge of the lid body 2 and near the mating surface;
Reference numeral 6 denotes a locking protrusion that releasably locks the latch 4, and is provided in a protruding manner on the main body 1.

The main body 1 and the lid 2 are adapted to be brought together when in the closed state by mating surfaces provided around the respective openings.

The mating surface of the lid 2 on which the latch 4 is protruded is provided with a protrusion 7 on the outside and a recessed step 8 on the inside. On the other hand, the mating surface on the main body 1 side is provided with a concave step 9 on the outside that fits into the above-mentioned protrusion 7, and a protrusion 10 on the inside into which the concave step 8 on the lid body 2 side fits. There is. The protrusion 7a and the recessed step 9a corresponding to the hinge 5 have a step-like wide surface.

Among the protrusions 7 on the mating surfaces of the lid 2, the width of at least the protrusion 7a corresponding to the hinge 5 is A, the width in the bending direction of the hinge 5 is B, and the average thickness of the lid 2 is t. When these dimensional relationships are 0.5B
<A>2.2t, preferably 1.2B<A>2.5t.

The lid body 2 having the above-mentioned dimensional relationship is formed by blow molding using left and right molds 11 and 12, as shown in FIG. At this time, hinge 5 of latch 4
is compressed by both molds 11 and 12, and the accumulated resin moves to the cavity side of the lid body 2, but there is a protrusion 7a on the outside of the mating surface of the lid body 2, and this protrusion Width A of 7a is 0.5 of width B of hinge 5
Since the thickness is more than 2.2 times the average thickness of the lid body 2, the resin that has moved toward the cavity side of the lid body 2 remains in the cavity of the protrusion 7a, and does not move along the inner surface of the

In order to further improve the above effect, the width C from the mating surface of the container to the base of the hinge 5 should be
The width A may be 0.25 times or more.

In the above embodiment, the protruding part of the hinge 5 connecting the lid body 2 and the latch 3, which is particularly noticeable in appearance, was shown, but in the present invention, a member compressed during molding, such as a foldable The present invention can be applied to a hollow double-walled container having a handle member and a small lid member that closes a plug insertion opening formed near a mating surface of the container.

Effects of the invention According to the invention, when the hinge molded part is pinched off when the mold is closed during blow molding and the hinge molded part is compressed, the resin that has accumulated in this part moves toward the cavity side of the container such as the lid. The protrusions 7a on the mating surfaces remain within the cavity, and are prevented from moving along the inner surface of the cavity on the container side. Therefore, the movement of the resin prevents the streaks that have occurred on the surface of conventional containers. It is possible to prevent the generation of lines and obtain a hollow double-walled container with a clean appearance.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing the main parts of the present invention, Fig. 2 is a sectional view showing the blow molding state, Fig. 3 is a plan view showing the main body and lid in an open state, and Fig. 4 and the following are conventional examples. 4 is a perspective view, FIG. 5 is a sectional view, and FIG. 6 is a sectional view showing a state of blow molding. 1 is a main body, 2 is a lid, 4 is a latch, 5 is a hinge, 6 is a locking projection, 7 and 7a are protrusions, and 9 and 9a are recessed steps.

Claims (1)

[Scope of utility model registration request] The inner and outer walls of the main body and/or the lid are integrally molded with a concave cavity and a convex cavity from the parison, and at the outer edge of one of the main body or the lid,
In a hollow double-walled container in which a member compressed during molding, such as a latch, is integrally connected via a hinge located near the mating surface, the hinge protrudes on one of the mating surfaces of the main body or the lid. A protrusion with a width A that fits into the recessed part of the other mating surface is provided on the outside of the side mating surface, and the width A of this protrusion, the width B in the bending direction of the hinge, and the average wall thickness of the container are provided. A hollow double-walled container characterized in that the dimensional relationship with the thickness t is 0.5B<A>2.2t.