JPS6313500B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a sound absorbing board in which a large number of sound absorbing holes are carved on the surface of a board made of an inorganic material.

In conventional sound absorbing boards used for this type of ceiling material, etc., the entrance and the inner part of the sound absorbing hole 2 are of approximately uniform width, as shown in FIG.
It was not possible to increase the surface area of the sound absorption holes 2, and sufficient sound absorption performance could not be obtained.

The present invention has been made in view of the above-mentioned points, and its main purpose is to provide a method for manufacturing a sound-absorbing plate that improves sound-absorbing performance by increasing the surface area of sound-absorbing holes.

Embodiments of the present invention will be described below based on the drawings. In the method for manufacturing a sound absorbing board according to the present invention, the circumferential surface of a jig 3 curved in an arc shape along one direction and having a large number of hole-drilling pins 4 implanted on one surface of the convex side is made of an inorganic material having sound absorbing properties. By sequentially pressing the material onto the surface of the plate 1, a sound absorbing hole 2 is formed into a bag-like shape, leaving a part of the back side of the plate 1, and the back part is wider than the entrance.
is formed on the plate material 1. As the board material 1, an inorganic material such as a gypsum board or an asbestos cement board is used. As shown in FIG. 2, sound absorbing holes 2 are provided at regular intervals over substantially the entire surface of the plate 1. The sound absorption holes 2 are each formed in a bag shape that opens only on the front side, and are wider at the back than at the entrance. That is, as shown in FIG. 2b, the sound absorption hole 2
In one direction of the board 1, the width of the entrance and the back part are approximately equal, and in the direction orthogonal to that direction on the surface of the board 1, the back part spreads back and forth from the entrance. Sound absorption hole 2
The inner base is curved into a fan shape. Sound absorption hole 2 like this
By making the inner part wider than the entrance, the sound absorption area is expanded and the sound absorption performance is improved, although the appearance remains the same as the conventional one.
That is, since inorganic materials such as gypsum board and asbestos cement board have sound absorbing properties, high sound absorbing performance can be obtained by expanding the sound absorbing area.

By the way, in order to form the sound absorption holes 2 as described above, a jig 3 whose surface is curved along one direction of the plate material 1 is used, as shown in FIG. That is, the jig 3 has an arc shape so as to come into contact with the plate material 1 at one point, and a large number of pins 4 for drilling holes are planted on the surface of the jig 3 at equal intervals. When this jig 3 is pressed against the plate material 1 along the circumferential surface of the jig 3 as shown in FIG. 3, the pins 4 gouge the plate material 1 and form the sound absorption holes 2. At this time, with the base of pin 4 as a fulcrum, pin 4
Since the tip moves in an arc, the sound-absorbing hole 2 is formed which widens deeper than the entrance as described above. It goes without saying that the length of the pin 4 is shorter than the thickness of the plate material 1. That is, as the inorganic material used in the present invention, a material is used in which the sound absorbing hole 2 can be easily bored by using the drilling pin 4 as described above.

As described above, since the sound absorption holes are formed in a bag shape so that the inner part is wider than the entrance, a large sound absorption area can be obtained, and as shown by A in Figure 4, the sound absorption coefficient of the conventional sound absorption board is lowered. The sound absorption coefficient was improved by 2 to 2.5 times over almost the entire frequency range.

As described above, the present invention provides a method for connecting the peripheral surface of the jig, which is curved in an arc shape along one direction and has a number of hole-drilling pins implanted on one surface of the convex side, to the surface of a plate material of an inorganic material having sound absorbing properties. By sequentially pressing the sound absorbing hole into the board, a part of the back side of the board is left behind, and a sound absorbing hole is formed in the board, which is bag-shaped and whose inner part is wider than the entrance.
It is possible to drill a large number of sound-absorbing holes with high sound-absorbing efficiency in a shape where the inner part is wider than the entrance in one operation, which has the advantage of high work efficiency.

[Brief explanation of the drawing]

1A and 1B are a sectional view and a bottom view showing a conventional example, FIGS. 2A and 2B are a sectional view and a bottom view showing an example of a sound absorbing plate manufactured according to the present invention, and FIG. FIG. 4 is a schematic explanatory diagram showing one embodiment of the present invention, and FIG. 4 is an explanatory diagram of the operation of the sound absorbing plate manufactured according to the present invention. 1 is a plate material, 2 is a sound absorption hole, 3 is a jig, and 4 is a pin.

Claims (1)

[Claims] 1. By sequentially pressing the circumferential surface of a jig, which is curved in an arc along one direction and has a large number of hole-drilling pins implanted on one surface of the convex side, onto the surface of a plate made of an inorganic material that has sound absorbing properties, the plate material is A method for manufacturing a sound absorbing board, characterized in that a sound absorbing hole is formed in a board material, leaving a part of the back side of the board, and having a bag-like sound absorbing hole whose inner part is wider than the entrance.