JPS6226239B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a speaker box net plate mounting device, in which a recessed portion for engagement can be formed by sink marks generated during resin cooling.

Conventionally, when attaching a net plate to a speaker box, a cylindrical mounting part 2 is attached to the front plate 1 of the speaker box with screws 3, as shown in FIG. Exit 5
screw in the pin 5 having the b and flange 5c, press fit the pin 5 into the center hole 2a of the mounting part 2, and insert the concave portion 5d below the bulge 5b into the center hole 2a of the mounting part 2.
He is trying to engage with a protrusion 2b provided inside.

However, when constructing such a pin 5, two molding molds 6a, 6 are used as shown in FIG.
It is necessary to butt the pins 5 together, pour resin into the recesses 7 between them, and separate the molds in the directions of the arrows.
d, it was extremely difficult to integrally mold the net plate 4 and the pin 5 with resin.

The present invention provides a method for manufacturing a speaker box net plate mounting device that solves these problems.

Embodiments of the present invention will be described below with reference to FIG.

In FIG. 3, 8 is a composite part of a net plate and a pin integrally molded with resin, 8a is a net plate part formed in a frame shape that covers the entire front surface of the speaker box, and 8b is a net plate part 8a. 8c is a recess formed at the top of the pin part 8b, and 8d is a recess 8.
A recess 8e formed in the net board opposite to c is a thick part that is relatively thicker than the tip and rear ends of the pin part 8b by providing the recesses 8c and 8d. be.

To resin mold such a composite part 8, molds 9a and 9b as shown in FIG. 4 may be used.
At this time, it is sufficient to simply provide the mold 9a with a cylindrical recess 9c corresponding to the pin portion 8b. That is, there is no need to provide any unevenness on the inner circumferential surface of the recess 9c.

In this state, resin is poured into the recess between the molds 9a and 9b, each of the molds 9a and 9b is separated in the direction of the arrow, and the composite part 8 is released and cooled. Because the meat is thick, the pin part 8a
The contraction is delayed compared to both ends of the pin part 8, and as a result, the pin part 8
After both ends of a solidify, the surface of the thick portion 8e contracts inward when it is semi-solid. Therefore, a recess 8f, commonly called a sink mark, is formed around the thick portion 8e.

Therefore, if this pin part 8a is press-fitted into the center hole 2a of the mounting part 2 shown in FIG.
The concave portion 8f of the portion is engaged with the protrusion 2b, and the net board can be detachably attached as in the conventional case.

As described above, the present invention provides a resin net plate integrally formed with a cylindrical attachment part provided on a speaker box, a protrusion provided in a center hole of this attachment part, and a pin fitted into the center hole. a first recess is formed in the top of the pin, and the first recess is formed in the top of the pin;
By forming a second recess in the net board opposite to the recess, a thick part is formed between the first recess and the second recess, and then the resin is cooled around the outer periphery of the thick part. Since the recess for engagement is formed by the sink mark that occurs, there is no need to provide a protrusion on the molding die to form the recess for engagement, and the mold shape can be made extremely simple. I can do it. Therefore, the net board and the pins can be integrally molded from resin, and as a result, the manufacturing of the net board can be significantly facilitated. Furthermore, by fitting the engagement recess with the protrusion provided in the center hole of the attachment component, the net board and the speaker box can be reliably attached.

[Brief explanation of the drawing]

Fig. 1 is an exploded sectional view of the conventional example, Fig. 2 is a sectional view showing the main parts of the manufacturing mold, Fig. 3 is a sectional view of the main parts of an embodiment of the present invention, and Fig. 4 is the manufacturing mold. It is a sectional view showing a mold. 8...Composite part, 8a...Net board part, 8b...
...Pin portion, 8c, 8d...Concave portion, 8e...Thick wall portion, 8f...Concave portion due to sink marks.

Claims (1)

[Claims] 1. A protrusion is provided on the inner periphery of a center hole of a cylindrical attachment part provided on a speaker box, a pin that fits into the center hole is formed on a resin net plate, and a first recess is formed at the top of the pin. At the same time, a second recess is formed in the net board opposite to the first recess, thereby forming a thick part between the first recess and the second recess. A method for manufacturing a speaker box net plate mounting device in which a concave portion for engagement due to sink marks generated during resin cooling is formed on the outer periphery.