JPH05223255A - Home-use foot warmer frame - Google Patents

Abstract

PURPOSE:To furnish a hollow home-use foot warmer frame which is light in weight and has large rigidity and in the corner part of which no shrinkage occurs. CONSTITUTION:A peripheral frame 2 and internal crosspieces 3 arranged in the shape of a lattice inside the peripheral frame 2 are provided. Both the peripheral frame 2 and the internal crosspieces 3 have hollow holes 5 being shaped to be continuous and formed by injecting gas into uncured resin in the process of infection molding. By injecting the gas into the uncured resin in the process of the injection molding, shrinkage is prevented from occurring in a corner part. Since monolithic molding can be applied, the wall thickness of a wall part can be made small and the weight is made light.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a home natatsu frame.

[0002]

2. Description of the Related Art Conventionally, in a plastic home natatsu frame, a lid frame body for covering the groove portion is generally bonded to a frame body having the groove portion to form a hollow structure. Then, as such a home shredder frame, for example, as shown in FIG. 6, a plastic frame main body b having an upward opening groove portion a,
A frame lid body d which is adhered to the groove a of the frame body b as a lid-like shape.
There was one with and.

[0003]

However, in the conventional home natura frame as described above, since the frame body b and the frame lid d are separately formed, there is a drawback that the number of parts is large, and a bonding work step is required. There was a drawback. Further, in order to obtain a strong adhesive force and great rigidity, ribs or the like are required on the wall portion of the frame main body b and the frame lid d, and there is a drawback that the weight increases.

Further, as shown in FIG. 7, there is a drawback that shrinkage h, h occurs in the vicinity of the corner k of the frame body b formed by injection molding.

Therefore, the present invention solves the above-mentioned drawbacks,
It is an object of the present invention to provide a home pallet frame that is lightweight and has high rigidity, with no shrinkage at the corners.

[0006]

A home natura frame according to the present invention comprises a peripheral frame and an inner shaft arranged in a lattice pattern inside the peripheral frame, and the peripheral frame and the inner frame. It has hollow holes formed by gas injection into the uncured resin during injection molding, which are in communication with both the shell and the shell.

[0007]

With the above-mentioned structure, the wall pressure of the wall portion can be reduced, and the overall structure is lightweight and has great rigidity. Since the hollow holes are formed by injecting gas into the uncured resin during injection molding, the wall of the corner portion is pressed from the inside to the outside mold by the pressure of gas during the injection forming process, and The shape is accurate. And the whole can be easily integrally molded. The shape of the mold used is also simple.

[0008]

The present invention will be described in detail below with reference to the drawings showing the embodiments.

FIG. 1 shows an embodiment of a home natura frame according to the present invention. The home natura frame 1 includes a peripheral frame 2 having a rectangular shape in plan view, and a grid pattern inside the peripheral frame 2. The inner shell 3 is arranged.

A top plate (not shown) or the like is placed on the upper side of the platform 5 and the four corners C of the peripheral frame 2 are provided with separate leg portions 4 ... It is fitted from.

However, as shown in FIG. 2, the home porcelain frame 1 is integrally formed of resin. In addition, the peripheral frame 2 and the inner sleeve 3 are each in the shape of a rectangular tube, and have hollow holes 5 communicating with both the peripheral frame 2 and the inner sleeve 3 inside.

The hollow holes 5 are formed by injecting gas into the uncured resin during injection molding.

Injection holes 7 ... Are formed in the wall portion of the peripheral frame 2 and the wall portions of the inner shells 3 ... Where the gas for forming the hollow holes 5 is injected.

Any resin may be used as the resin for forming the home moat frame 1 as long as it is a thermoplastic resin, for example, polypropylene, polycarbonate, A
It is also preferable to use BS, polystyrene, acrylic or the like.

Next, in the corner portions C ... Of the peripheral frame 2, there are formed mounting holes 6 ... A partition wall 8 is provided between the mounting hole 6 and the hollow hole 5.

Further, a wall portion 11 for forming a downward-opening-shaped recess is provided at the upper end of the inner shell 3 ... It is formed integrally with the part. Then, the heat generating unit having the protection net portion 9 in the downward opening-shaped recess formed by the wall portion 11
10 is installed.

The leg portion 4 is integrally formed of a thermoplastic resin similarly to the above-mentioned home natura frame 1, and has a hollow portion 12 formed therein by injecting gas into an uncured resin which is being injection-molded.
have. A hole 13 is opened in the upper wall portion where the gas is injected.

In the case of injection-molding the home moat frame of the present invention, as shown in FIG. 3, an upper mold 14 and a lower metal mold in which a cavity 16 having the same outer shape as that of the home moat frame 1 is formed. Use mold 15. At least one of the upper and lower molds 14, 15 is provided with one or a plurality of gas injection passages 17.

The molten thermoplastic resin P is injected and injected into the cavity 16 from a resin injection portion (not shown), and the flow of the thermoplastic resin P is controlled from the gas injection passage 17 into the flow. Gas pressurized at pressure is continuously injected.

It is also desirable that the molten thermoplastic resin P is injected and injected from the resin injection portion to fill the thermoplastic resin P, and then gas is injected from the gas injection passage 17.

Thus, as shown in FIG. 3, the molten thermoplastic resin P having the gas chamber 21 filled with the gas is filled in the cavity 16. The gas chamber 21 filled with this gas is formed in a continuous manner in the cavity 16 that is continuous in the vertical and horizontal directions.

Next, the thermoplastic resin P is solidified while maintaining the pressure of the gas in the air chamber 21. Therefore, the volume decrease due to the volume contraction due to the solidification of the thermoplastic resin P is compensated by the pressure of the held gas, and the thermoplastic resin P is solidified while being held in the shape of the cavity 16.

That is, the layer of the thermoplastic resin P is solidified while being pressed against the inner surface of the cavity 16 by the pressure of the gas inside thereof. Therefore, so-called "shrinkage" does not occur in the vicinity of the corners 18, which are relatively thick.

After solidification of the thermoplastic resin P, the air chamber
The pressure of the gas in 21 is made the same as that of the outside air, and the home tatami frame is taken out of the mold.

As shown in FIGS. 1 and 2, the home natura frame according to the present invention is surrounded by a flat surface without any shrinkage in the corners C ... and other corners. Become. Further, injection holes 7 ... Are opened at the location where the gas injection passage 17 is provided.

1 and 2, the injection holes 7 ... Are formed at a plurality of locations, but it is also preferable to form the injection holes 7 at only one location. That is, in that case, the gas injection passage 17 is provided at only one place.

The gas injected from the gas injection passage 17 is an inert gas, preferably nitrogen gas.

Further, in the illustrated example, the gas injection passage 17 is provided in the upper mold 14 in a penetrating manner, but it is also preferable to provide this in the lower mold 15 in a penetrating manner. Further, although the gas injection passage 17 is arranged at a position different from the resin injection portion for injecting and injecting the thermoplastic resin P, it is desirable to arrange the gas injection passage 17 in the resin injection portion.

Next, FIG. 4 and FIG. 5 show another embodiment of the home natura frame of the present invention. In this embodiment, the leg portion 4 as a separate body is swingably attached around the axis L of the corner portion C of the peripheral frame 2, and the leg portion 4 is swung and folded to store. It is said to be easy.

This leg portion 4 is also integrally formed of a thermoplastic resin, has a hollow portion 19 formed inside by injection of gas into the uncured resin being injection-molded, and has a wall portion at the upper end. A hole 20 formed by an injection passage into which a gas is injected is opened in.

[0031]

The present invention has the following significant effects with the above-mentioned configuration.

It is possible to integrally form a hollow home tattoo frame. As a result, the overall weight can be reduced and the rigidity can be increased.

Further, the step of adhering after molding is unnecessary, the adhering rib can be omitted, and the wall thickness can be reduced. Then, the number of parts is reduced.

Further, no shrinkage occurs at the corners of the wall and a smooth surface is formed.

Despite having the hollow holes 5,
No core is required for injection molding. Therefore, the mold becomes simple.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a home natura frame of the present invention.

FIG. 2 is a partially cutaway perspective view.

FIG. 3 is a cross-sectional view illustrating injection molding.

FIG. 4 is a perspective view showing a main part of another embodiment.

FIG. 5 is a partially cutaway perspective view showing a leg portion of another embodiment.

FIG. 6 is a diagram showing a conventional example.

FIG. 7 is a cross-sectional view showing a main part of a conventional example.

[Explanation of symbols]

 2 Surrounding frame 3 Inner shell 5 Hollow hole

Claims (1)

[Claims] 1. A peripheral frame (2) and an inner shaft (3) arranged in a grid pattern inside the peripheral frame (2), and connected to both the peripheral frame (2) and the inner shaft (3). Of the above, which has a hollow hole 5 formed by gas injection into an uncured resin during injection molding.