JPH03164638A - Silencing type ventilator - Google Patents

Abstract

PURPOSE:To absorb a sound by a blower body it self and to simultaneously cope with frost deposition of the body by providing a plurality of doughnut- shaped ribs for forming a plurality of air chambers between the outer periphery of the cylindrical body and a cover, and integrally molding the body in a porous structure having a porous layer in which its specific weight is continuously varied in thickness or plane direction of the layer. CONSTITUTION:A cylindrical blower body 9 and doughnut-shape ribs 9a formed on the outer periphery of the body are integrally molded in a porous structure having a porous layer in which its specific weight is continuously varied in thickness or plane direction of the layer. Thus, the body 9 is composed of the porous structure, air chambers 20 are further provided in the outer periphery, and the outer periphery is covered with a cover A15 made of a steel plate. A noise generated from a fan 10 is absorbed by the body, the pair passed through the body 9 is heat insulated by the chambers 20 to prevent frost deposition on the outer periphery of the cover 15. The ribs 9a are not only used to increase the strength of the body and to form the chambers 20 but also used to prevent flanking when the length of the body is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a noise-reducing ventilation device installed in the middle of a ventilation duct.

C. Prior Art] Fig. 5 and Fig. 6 are, for example,
The conventional ventilation system of this kind shown in Publication No. 2 is shown, and No. 5
The figure is a cross-sectional view of the sound-absorbing box, and Figure 6 is a perspective view. Flange, (5) is the mounting flange part, (6) is the blower body, (
7) is a ventilation duct, and (8) is a ceiling hanging bolt.

Next, the operation will be explained. When the blower operates, air from the suction side ventilation duct (7) is connected to the flange (4).
) is sucked into the sound-absorbing box body (1) attached to the sound absorbing box body (1) through the suction port (3), and is further sucked into the ventilation blower body (6) through the ventilation duct (7).

The air discharged from the ventilation blower body (6) is passed through the ventilation duct (7) which is attached to its outlet by a connecting flange (4).
) is discharged. At this time, the noise caused by the direction change or merging of airflow in the sound-absorbing box body (1) is absorbed by the sound-absorbing material (2) attached to the inner surface of the sound-absorbing box body (1).

[Problems to be Solved by the Invention] Since the conventional ventilation system was configured as described above, although the noise caused by the airflow passing through the sound-absorbing box body (1) is reduced, the noise generated in the blower body is Noise is not absorbed. Further, when cold air is supplied from outside, there are problems such as the need to attach a heat insulating material to the inner or outer surface of the blower body to prevent dew condensation on the outer surface of the blower body.

This invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a noise-reducing ventilation device that can absorb sound within the blower itself and also take measures against dew condensation on the blower main body.

[Means for Solving the Problems] A noise-reducing ventilation device according to the present invention has a structure in which a cylindrical ventilation device body having an axial flow fan and a drive motor therein has a cylindrical ventilator body having an outer periphery and a cover made of a steel plate that covers the cylindrical ventilation device body. A plurality of donut-shaped ribs constituting a plurality of air chambers are provided in the main body,
It is an integrally molded porous structure having a porous layer whose specific gravity is continuously varied in the thickness direction or surface direction of the layer.

A noise-reducing ventilation device according to another aspect of the present invention is a flange-shaped ventilation device having a groove opening outward on both end surfaces or one end surface of the main body. A main body having substantially the same shape as the above-mentioned flange-shaped portion is positioned with the packing fitted in the groove of the flange-shaped portion and the flange-shaped end faces abutting each other.

[Function] The noise-reducing ventilation device of the present invention has a plurality of air chambers formed between the blower main body formed of a porous structure and a steel plate cover provided on the outer periphery of the blower main body. This eliminates the axial fan noise generated by the axial fan and prevents dew condensation from forming on the outer surface of the steel plate cover.

Further, a noise-reducing ventilation device according to another invention of the present invention includes:
Since a main body having substantially the same shape as the blower main body is disposed on one or both of the blower bodies, the silencing effect is further improved, and in particular, by disposing this on the indoor side, noise leaking into the room is reduced.

[Example] An embodiment of the present invention will be described below with reference to the drawings.

Fig. 1 is a sectional view showing an embodiment of the present invention, and Fig. 2 is an exploded perspective view thereof. These blower bodies (
9) and the donut-shaped rib (9a) are integrally formed of a porous structure having a porous layer whose specific gravity is continuously varied in the thickness direction or surface direction of the layer. (10) is an axial fan, (11) is a drive motor that rotationally drives this axial fan (10), and (12) is this drive motor (11).
) with screws (13) and mounted inside the blower body (9) with screws (14), (15)
(16) is a cover A made of a steel plate that covers the outer periphery of the donut-shaped rib (9a), and (16) is attached by screws (17) with the flange-shaped outer periphery fitting on both end surfaces of the cover A (15). , a cover B made of steel plate with an opening approximately equal to the inner diameter of the blower body (9) in the center, (4) is removably attached to the opening of this cover B (16) with screws (18). The duct connection flange (7) is the ventilation duct connected to this connection flange (4), (
19) is a heat insulating material covering the outer periphery of the ventilation duct (7), and (20) is formed by the outer periphery of the blower body (9), the donut-shaped rib (9a), and the steel plate cover A (15). Multiple air chambers.

(23) is a screwdriver for removing the main body.

Claims (2)

[Claims] (1) Made of steel plate, having a cylindrical body, an axial flow fan installed in the body, a drive motor that rotates the fan, and flanges that cover the outer circumference of the body and connect ventilation ducts to both end faces. In a ventilation device equipped with a cover, a plurality of donut-shaped ribs forming a plurality of air chambers between the cylindrical main body and the cover are provided on the outer periphery of the cylindrical main body, and the main body is A noise-reducing ventilation device characterized by being integrally molded with a porous structure having a porous layer that changes continuously in the direction or surface direction. (2) Both end faces or one end face of the main body have a flange shape with a groove opening outward, and both end faces or one end face of the main body have approximately the same shape and do not have an axial fan or drive motor inside. 2. The noise-reducing ventilation device according to claim 1, wherein the soundproof main body is positioned with its flange-shaped end surfaces abutting each other with the packing fitted into the groove of the flange-shaped portion.