JPS5936840B2 - Warpage prevention device for thin casing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a deflection prevention device for a thin casing made of synthetic resin.

Electronic desktop calculators, abbreviated as calculators, are widely used.

Recently, various improvements have been made to this calculator in order to make it more compact. As a result, the casings of these calculators began to be made as thin as possible. However, since the calculator housing is thinly molded from synthetic resin, "D" is likely to occur due to internal distortion during molding.

In particular, since the base of the casing has a thin structure as shown in FIG. 1, "D" as shown in FIG. 2 is likely to occur. Conventionally, the method of correcting this "strain" was to turn the base 1 upside down and bridge it over two platforms 2, 2, as shown in Figure 3, and place a weight 3 on the center of the top surface of the base 1, placing it upside down. ZoD
I'm trying to make it happen.

However, this straightening method requires a lot of time and effort, the straightening is unstable, and it is not possible to perform proper straightening according to the amount of warp D. Another drawback was that even if it could be temporarily corrected, the "D" would reappear over time. especially,
If you place it near a sunny window or in a place with high room temperature, it will return to its original state.
Unfortunately, the above-mentioned correction methods were only temporary methods. The present invention has been made in view of the above-mentioned circumstances, and its purpose is to solve the problem that the occurrence of "slips" that appear on thin casings made of synthetic resin require special correction work. To provide a crash prevention device with a thin casing that can reliably prevent collapse in a stable state.

Hereinafter, one embodiment of the present invention will be described based on FIGS. 4 to 6.

FIG. 4 shows the assembled state of the housing 1 of the electronic desktop calculator.

This casing 1 is composed of a spacer 2 and an upper cover 3, and the entire casing 1 is formed to be thin. The base 2 is integrally molded from synthetic resin and has an upper edge rib 4 formed around its entire circumference. Furthermore, the upper edge rib 4 forms a projecting edge 5 that protrudes upward over the entire circumference.The upper cover 3 is fitted onto the projecting edge 5. . Furthermore, as shown in FIG. 5, a plurality of notches 6 are formed in the protruding edge portion 5 of the upper edge rib 4 to relieve stress due to internal strain during molding.

By providing the tabs b1 and the notches 6...1
This is intended to prevent ``friction'' caused by internal strain stress during molding. Therefore, notch 6...
The formation position of * is appropriately selected so that the stress of internal strain is not accumulated. For example, as shown in the drawings, a plurality of notches 6 are formed in the upper edge rib 4 on both sides along the longitudinal direction.
form. Further, the upper cover 3 is also integrally molded from synthetic resin.

A lower edge rib 7 is formed around the entire circumference of the upper cover 3.1 This lower edge rib 7 is connected to the projecting edge 5 of the base 2.
It is designed to be fitted into the Further, engagement pieces 8 and 9 are provided on the lower edge rib 7 and the projecting edge portion 5 that fit together, respectively.
is formed so that the upper cover 3 is automatically engaged when the upper cover 3 is pushed in. A pair of protrusions 10, 10, 11, 11 are formed on the left and right sides of the upper cover 3 on the inside of both ends in the longitudinal direction.

Further, the protrusions 10, 10, 11, 11 are connected to the housing 1.
The sleeve is shaped so as to press the upper edge rib 7 of the base 2 outward when assembled.

That is, the wall surface 12 that presses against the upper edge rib 7 is inclined as shown in FIG. By attaching the upper cover 3 to the base 2, the base 2 is pushed outward in the longitudinal direction a, thereby suppressing the length D in the longitudinal direction. In addition, the outer surface of the upper cover 3 is made of metal,
For example, a decorative plate 13 made of aluminum is adhered and fixed.

The decorative board 13 reinforces the upper cover 3 and prevents not only the upper cover 3 but also the base 2 from being bent. In the case 1 having the above configuration, first, a plurality of notches 6 are formed in the upper edge rib 4 of the base 2.
... is formed, and the internal strain generated during molding is released to each of the notches 6, so that the internal strain is not accumulated. Therefore, if notches 6 are not formed, a large "socket" is formed as shown by the solid line in Fig. 5.
It is possible to prevent this from appearing, and to achieve the state shown by the two-dot chain line in the figure. In other words, even if a small amount of "SoD] remains, it can be maintained in a flat state that can be ignored. Since the width of the base 2 is short, "SoV)] is small, and the "SoB" due to the notch is small. There is no need to try to prevent it, but
If it is relatively long, cutouts 6 may also be provided in the upper edge rib 4 along the width to prevent "slip".

In addition, in the case 1, inside the upper cover 3,
Since the upper edge rib 7 of the base 2 is provided with projections 10, 10, 11, 11 that press against it and expand outward, the cover 3
If you attach it to the base 2, the longitudinal direction of the base 2
” can be suppressed.

Therefore, the action of these protrusions 10, 10, 11, 11 is as follows:
Coupled with the action of the notch 6 above, the base 2 is securely
Noso D can be prevented. In addition, the above case 1
In this case, a decorative plate 13 which also serves as reinforcement is attached and fixed to the outer surface of the upper cover 3, so that the upper cover 3 is strengthened and the upper cover 3 itself is prevented from "deforming". do.

Furthermore, by making the upper cover 3 strong, 1
This ensures the operation of the corrective projections 10, 10, 11, 11, and indirectly suppresses the "slip" of the base 2. As explained above, according to the present invention, the notch formed in the upper edge rib of the base can greatly reduce the "b" of the base itself, where the "b" is most likely to occur. It is something.

Furthermore, since a correction protrusion is provided on the inside of the upper cover to suppress the "bending" of the base, it is possible to more reliably prevent the "bending" of the base. In addition, since the reinforcing decorative board is fixed on the outer surface of the upper cover,
In addition to preventing the upper cover from collapsing, indirectly,
It is possible to prevent the base from collapsing.In this way, it is possible to prevent the casing from collapsing, and there is no backlash due to heat.
Since the normal shape can be maintained, built-in components etc. can be reliably protected and the lifespan can be extended.

In addition, the above-mentioned "b" prevention means can be completed by assembling the casing, so it does not require any special correction work, and has various excellent effects.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the base of a conventional housing, FIG. 2 is a sectional view of the base, FIG. 3 is an explanatory diagram of a conventional method for straightening D, and FIG. 4 is an illustration of the present invention. FIG. 5 is a side sectional view of a casing showing one embodiment; FIG. 5 is a side view showing the base of the casing in the same embodiment; FIG. 6 is a part of the casing according to the embodiment. FIG. 2 is an enlarged cross-sectional view. 1... Housing, 2... Base, 3... Upper cover,
4... Upper edge rib, 5... Projection edge, 6... Notch,
7... Lower edge rib, 10, 11... Protrusion, 13...
Decorative board.

Claims (1)

[Claims] 1. A casing consisting of a thin synthetic resin base integrally molded with an upper edge rib and an upper cover attached to the base; A warpage prevention device for a thin casing, characterized in that it is equipped with a notch for removing internal distortion. 2. A casing consisting of a thin synthetic resin base integrally molded with an upper edge rib and an upper cover attached to this base, and an internal strain eliminating method formed on the upper edge rib of the base. a notch and formed on the inside of said top cover;
A warpage prevention device for a thin casing, characterized in that the device comprises a protrusion that pushes the upper edge rib of the base outward to correct warpage of the base when the casing is assembled. 3. A casing consisting of a thin synthetic resin base integrally molded with an upper edge rib, and an upper cover attached to this base, and a housing for removing internal strain formed on the upper edge rib of the base. A warpage prevention device for a thin casing, characterized in that it comprises a notch and a decorative plate that is adhered and fixed to the outer surface of the upper cover to reinforce the upper cover and prevent the occurrence of warpage. 4 A casing consisting of a thin base made of synthetic resin integrally molded with an upper edge rib, an upper cover attached to this base, and an inner strain relief plate formed on the upper edge rib of the base. a notch, a protrusion formed on the inside of the upper cover that pushes the upper edge rib of the base outward to correct the force of the base when the casing is assembled, and a protrusion fixed to the outer surface of the upper cover. What is claimed is: 1. A warpage prevention device for a thin casing, characterized in that it is equipped with a decorative plate that reinforces the upper cover and prevents the occurrence of warpage.