JPH0461297A - Reinforcing structure of plastic molded shaft - Google Patents

Abstract

PURPOSE:To raise the strength of a molded shaft and to improve the mounting effective area of a printed board by inserting a supply material having substantially the same inner diameter as the profile of the shaft into the shaft, and securing the material to the shaft. CONSTITUTION:The inner diameter of a reinforcing material 3 to be engaged with a molding shaft 2 is formed substantially in the same shape as the profile of the shaft 2, the material 3 is inserted into the shaft 2, a printed board 4 is placed on the shaft 2, and the board 4 is clamped at the shaft 2 with screws 5. For example, the thickness of the shaft 2 is so formed as not to cause a contraction to 4.8mm in diameter. Since the screw 5 is formed to 2.5mm in outer diameter, a hollow hole 2-1 is formed to 2.3mm of inner diameter. After the material 3 is inserted into the shaft 2, the screws 5 are inserted to holes 4-l formed at the board 4 to be mounted at the shaft 2 to increase the thickness of the shaft 2 and to lightly press the inner diameter of the material 3, and the material 3 is reversely press-fitted in the shaft 2 to secure the material 3.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a structure for reinforcing a molding shaft of a molded article made of a plastic material.

[Conventional technology]

In recent years, as products have become lighter, thinner, shorter and smaller, products made of metal materials have been replaced by plastic molded products, and there has been remarkable progress in replacing them.

For example, if the molded product is a case of a communication terminal device such as a telephone, accessories such as a printed circuit board and a speaker are attached to a molded product made of a general IJ plastic material.

Conventionally, the method of fixing this equipment to the case is as follows:
As shown in FIG. 7, a molding shaft 2 to be fixed to the case is provided, and a hollow hole 2 is provided in the molding shaft 2 to form the molding shaft 2, for example, as shown in FIG. The usual method is to fix the printed circuit board 4 to the molding shaft 2 with screws 5. Note that the same applies when fixing other equipment.

If the molded product is a case for a communication terminal device such as a telephone, the surface of the molded product is naturally required to have an aesthetic appearance.

However, if a molding shaft for fixing the molded product is provided on the back side of the case, as shown in FIG. , There are 6 damage to the appearance of the case, and -1.
As a countermeasure for this problem, by considering the thickness of the forming shaft 2 and making the forming shaft 2 thinner, it is possible to prevent pi)y(3). (screw the item),′
If you try to fix it to the molding shaft with 2. :yo-], the tightening torque of the screw will be too high.2. Molded shaft: 5 cracks, 1-bi etc. are produced. As a result, the tightening force of the screw 5 becomes weaker, and in some cases, the screw 5 may fall off.

Further, as shown in FIG. 9, the printed circuit boards 4 and the printed circuit boards 7 may be fixed in an overlapping manner. In such a case, in order to fix the printed circuit board 7 to the case 1, the molding shaft naturally becomes longer, and the strength of the molding shaft must be increased by 1°.In addition to the problem of pickets 6 on the surface of the case, , the diameter of the hole 4-2 for passing the molded shaft 2-2 on the printed circuit board 4 must be adjusted accordingly, and the diameter of the hole 4-2 for passing the molded shaft 2-2 must be adjusted accordingly. The effective mounting area of electronic components (not shown) such as capacitor resistors is reduced, and miniaturization of the cavity 1 is hindered. 1
[Problems to be Solved by the Invention] ■-As shown in Figures 6 and 7, in the prior art, the molded shaft 2 for fixing the equipment has a hollow hole perpendicular to the shaft. 2-1 is provided.

This hollow hole 2-1c: The screw 5 is inserted and tightened. 3. Therefore, the forming shaft 2 must be strong enough to withstand the tightening torque of the screw 5.

A solution to this problem is to make the C1 forming shaft 2 thicker, but the surface of the case with two forming shafts installed has sink marks 6 as large as 1'16 as shown in Figure 8. The appearance becomes unfavorable.

On the other hand, if the thickness of the molding shaft 2 is made thin enough to prevent sink marks 6 from occurring, the molding shaft 2 will crack due to the tightening force of the screw 5.
Cracks occur and the purpose of fixing the equipment cannot be achieved.

Furthermore, when using printed circuit boards in multiple stages, do not make holes in the lower printed circuit board to pass through the molded shaft provided to fix the upper printed circuit board.
Therefore, if the molded shaft winding is made thicker, the diameter of the printed circuit board t4 of the F stage will become larger, and the effective mounting area of the G stage will become smaller.

The present invention increases the strength of two molded shafts, and also increases the strength of one hublin.
One object of the present invention is to provide a reinforcing structure for a plastic molded shaft that increases the effective mounting area of a board.

[Means to solve the problem]

1] The object of the present invention is a reinforcement structure for a plastic molded shaft, which is provided with a molded shaft for fixing equipment with screws to a case molded from a plastic monthly charge, and the outer shape of the molded shaft is approximately the same as that of the molded shaft. This is accomplished by inserting a reinforcing material having the same inner diameter into the forming shaft, and fixing the reinforcing material to the forming shaft.

[Effect]

Insert a reinforcing material into the molded shaft provided in the case 2, and attach it by hand or glue.The thickness of the molded shaft increases from the number L2, for example, 4 The molded shaft cracks and cracks due to the tightening force of the screw. Even if a crack occurs, the reinforcing material covers the outer shape of the molded shaft 2 and remains press-fitted, so the tightening force of the screw will not loosen.

Further, when printed circuit boards are stacked in multiple stages, the molding shaft for fixing one stage of printed circuit boards can be made thinner, so that the effective mounting area of the lower stage of printed circuit boards can be increased.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Figure 1 is a perspective view of an embodiment of the present invention; Figure 2 is a cross-sectional view of the configuration shown in Figure 1 after assembly; Figures 3 and 4 are cross-sections showing other embodiments of the present invention. 5 are perspective views showing other embodiments of the reinforcing material of the present invention.

The caseco is molded from a plastic material, and a molded shaft 2 is provided on the back side of the case 1 for fixing four volumes of printed circuit boards. Although not shown, the printed circuit board 4 is equipped with necessary voltage components such as IC, transistors, capacitors, and resistors.
Each part is configured as a circuit using batters. Further, the printed substrate 1 has a structure in which it is fixed to the molding shaft 2 through a fixing hole 4-1, which fits with the molding @2 provided on the base 1.

Case 1. Hollow holes 2-1 are provided in advance in the molding@2 provided in the molding section 2 so that the screws 5 can be fastened thereto, and these can be easily constructed by using a molding die. Since case 1 is made of plastic material, screw 5 is a self-tapping screw. ') Hair shaping phase 2iJ
By inserting the screw into the provided hollow hole 2-1 and tightening the screw, the screw itself cuts a thread into the hollow hole.

On the other hand, molding@2. The inner diameter of the reinforcing moon 3 that fits into the molded shaft 2
The reinforcing material 3 is inserted into the forming shaft 2 as shown in FIG.
．． A printed circuit board 4 is placed on molding shaft 2 (1-) and fixed to molding shaft No. 2 with screws 5.

Note that in the present invention, the thickness of the molded shaft 2 is set to be φ4.8 mm without sink marks (-3), and the hollow hole 7.-,...,.1 is screwed. The outer diameter of 5 is φ2.6mm
, Hishiboo, ``'' and inside Wφ2. Take +3mm, '7
1. be. 1 Conventionally, the molding shaft 2 was configured to have a diameter of approximately 6 mmF, resulting in C5 [Yl and Fig. So 1゛The surface of game 1(,,]・etc.(-5 occurs,
The appearance of Case 1 was damaged” 1.7.

After inserting this reinforcing material 3 into the forming shaft No. 2,
1. 2.Thread the hole 4-1 t', -screw ") 1. Also, by attaching it to the molding shaft 2 15, the outer diameter of the molding shaft 2 becomes thicker, and the inner diameter of the reinforcing ring 3 becomes in a state where the hair is lightly pressed, and vice versa. The reinforcing material 3 is in the iE state with respect to the forming shaft 2, and the reinforcing material 3 is fixed.The reinforcing material 3 has an inner diameter of 4.85 mm and an outer diameter of 2. 3. 7mm. This press-fitting condition can be carried out by considering the reinforcement + 43, but if the inner diameter of the reinforcing material 3 is 1" larger than the forming shaft 2, the adhesive It may be fixed using

Furthermore, there is also a method of inserting the reinforcing member 3 into the molding shaft 2 and then applying heat to a part of the molding @2 or reinforcing 1:3 to melt part of the ζ plastic phase material and fixing 1 and fixing @:3.

Figure 3 1j is a diagram in which case 1 is stacked with Grishi 1 and board 1 in 77 stages;
The control plate "'l" is fixed to the molding shafts 2 and 8.
1] and 7-1 are provided. In addition, the printed circuit board 41
．． 1- is provided with a hole 4-2 through which the molding shaft 8 passes, and the length of the molding shaft 8 passing through the hole 4-2 is longer than the length of the molding shaft 2. As the length of the forming shaft becomes longer, sink marks are more likely to occur on the surface 1, so it is necessary to make the thickness of the oval shaft 8 as thin as possible. In addition, the hole 4-2 provided in the f+1 point board 4 through which the eight windings of the molded shaft are passed also increases the effective mounting area of the printed circuit board. It is necessary to keep it small from
From this point of view as well, it is better that the outer diameter of the molding@8 is smaller. The length L1 of the reinforcing material 3 inserted into this molding shaft 8 is the printed circuit board.
The length between 1 and the printed board 7 may be 2, or the length I between the case 1 and the printed circuit board 7 may be 2, but in order to increase the effective mounting area of the printed circuit board 4, , it is better to make it slightly longer than the length of the screw 5.

Further, as shown in FIG. 4, the reinforcing material 31- is pudding!・
By providing a support D3-3 for the board, it is also possible to improve the work of the group.

Next, the structural color of another embodiment with reinforcement +4 will be explained using FIG. Reinforcement material; slit-shaped groove 3'' in the axial direction of 3'
By providing the reinforcing member 3', the entire reinforcing member 3' plays a spring-like role. By doing so, when the reinforcing material 3' is inserted into the molded shaft 2,
The slit-shaped groove 3-2 opens, and it becomes 1::J.
The reinforcing material 3' is always in the state 1 in which the outer shape of the form 2 is tightened, and the reinforcing material 3'' is in a configuration that does not require methods such as adhesives or heat caulking to fix it.

The embodiments of the present invention have been described above using a reinforcing material molded from a plus rack material.

However, it is clear that a pipe made of metal material 9, such as aluminum comb, copper, iron, stainless steel, etc., may also be used. Further, an elastic body such as rubber may be used as the reinforcing material, but in this case, molding of the inner diameter of the rubber@2. It needs to be slightly smaller than the outer diameter of. Furthermore, by using vinyl chloride shade (σ) f-1-buta, the molded shaft can be reinforced without increasing the thickness of the reinforcing material. .

〔Effect of the invention〕

According to Fubenban, the molding shaft can be reinforced by inserting and fixing a reinforcing material into the molding shaft, and as a result, it is possible to make the molding shaft thinner, so the molding shaft can be molded. In cases ostensibly, this can be prevented from occurring.

In addition, by making the molding axis thinner, the effective mounting area of the printed circuit board can be greatly increased, and the case can be made smaller and more economical.

Furthermore, even if a crank etc. gets into the molded shaft, the molded shaft is tightened or glued with the reinforcing material, so the cracks in the molded shaft will not open, preventing screws from loosening or falling off. This makes it possible to improve quality.

[Brief explanation of the drawing]

Figure 1 is a perspective view of an embodiment of the present invention, Figure 2 is a sectional view after the string q of the configuration shown in Figure 1. Figures 3 and 4 show other embodiments of the present invention. 5 is a perspective view showing another example Δ of the reinforcing material of the present invention, FIG. 6 is a cross-sectional view of a molded shaft with a crack in Kumamoto, and FIG. Fig. 8 is a cross-sectional view showing a conventional structure with a crack, and Fig. 51 is a cross-sectional view showing a conventional structure with printed circuit boards stacked on top of each other. be. DESCRIPTION OF SYMBOLS 1... Case, 2, 8... Molded shaft, 3... Reinforcement material, 4.7... Printed circuit board, 5... Screw, 6...
・）Sorry. , -m- Patent Applicant Hitachi Telecom Technology Co., Ltd. Figure 1 Figure 3 Figure 61! I District 7

Claims (3)

[Claims] 1. A reinforcing structure for a plastic molded shaft that is provided with a molded shaft for fixing equipment with screws to a case molded from a plastic material, the molded shaft being provided with a reinforcing material having an inner diameter that is approximately the same as the outer diameter of the molded shaft. A reinforcing structure for a plastic molded shaft, characterized in that the reinforcing material is inserted into the molded shaft and fixed to the molded shaft. 2. 2. The reinforcing structure for a plastic molded shaft according to claim 1, wherein the reinforcing material is made of an elastic body. 3. 2. The reinforcing structure for a plastic molded shaft according to claim 1, wherein a slit-like groove is provided in a part of the reinforcing material.