JPH0754753Y2 - Silent type ventilation grill - Google Patents

Description

[Detailed Description of the Invention] [Industrial application] The present invention relates to improvement of the sound deadening effect in a sound deadening type ventilation grill comprising a sound deadening chamber and a grill attached to the sound deadening chamber to form an indoor ventilation hole. .

[Prior Art] A sound deadening type ventilation grille is connected to a blower as a ventilation function part by a ventilation duct, and constitutes a ventilation device as shown in, for example, Japanese Utility Model Publication No. 59-3310 and FIG. As shown in FIG. 7, a conventional sound deadening type ventilation grill has a connection port 32 for connecting to a blower 31 via a ventilation duct 30 on one side.
And has a box-shaped silencing chamber 33 having an open bottom surface, and a grill 34 that is attached to an opening portion on the bottom surface of the silencing chamber 33 and forms an indoor ventilation port. Inside the sound deadening chamber 33, a sound absorbing material 35 is attached to a portion corresponding to the ventilation passage.

In the above-described conventional sound deadening type ventilation grill, as shown in the figure, the sound deadening chamber 33 is attached to the greenery of the ceiling, etc., and the grill 34 is attached to the opening portion of the lower surface opened toward the room to perform the ventilation function. . The illustrated example shows a case where air is supplied from the outdoors to the room, and the flow of wind is in the direction of the arrow shown. The air flow from the blower 31 flowing into the muffling chamber 33 through the connection port 32 is changed in direction within the muffling chamber 33 by 90 ° and is blown out from the grill 34 to the room. The sound absorbing material 35 attached to the ventilation path of the muffling chamber 33 reduces noise generated when the air blower 31 operates and when air passes through the ventilation duct 30,
Sound is absorbed and reduced to maintain quietness in the room.

[Problems to be Solved by the Invention] The conventional sound deadening type ventilation grill is satisfactory because it has a sound deadening structure in which the sound absorbing material 35 is attached to the inner surface of the air deadening path of the sound deadening chamber 33 as long as the air deadening path is not narrowed. No silencing effect can be obtained. That is, the thickness and area of the sound absorbing material 35 cannot be so low as to attenuate low frequency noise due to restrictions such as securing ventilation passages and the space of the mounting portion, and can achieve sound reduction at a level of about 3 dB (A). Stays in. Further, as shown in FIG. 7, the ventilation flow flowing in from the connection port 32 causes a turbulent flow at the corners of the sound absorbing material 35 facing the connection opening 32 and the sound absorbing material 35 on the top side to generate noise. Therefore, the total effect on noise reduction is reduced.

The present invention has been made in order to solve such a conventional problem, and its purpose is to provide a silencing type ventilation grill excellent in silencing function in which the silencing chamber does not serve as a noise source and the silencing property of low frequency noise is good. It is to be.

[Means for Solving the Problems] A sound deadening type ventilation grill according to the present invention forms a space inside and has a cylindrical connection port for connecting a ventilation duct on one side,
A chamber having an opening on the other side that opens into the room and an inner wall of this chamber that guides the flow of air between the connection port and the opening, and forms a back air layer on the back side. It is equipped with an arc-shaped wind direction plate, a plurality of small holes are provided in the wind direction plate, a sound absorbing material is attached to the inner surface of the air passage formed by the wind direction plate and the inner surface of the chamber, and the connection port is a cross on the inner circumference. The sound absorbing cylinder made of glass wool and having a cover and a cover member covering the outer circumference and the side surface of the sound absorbing cylinder.

In addition, a space is formed inside, a cylindrical connection port for connecting a ventilation duct is provided on one side, and an opening portion that opens to the room is provided on the other side, and air between the connection port and the opening portion is provided. The chamber has a chamber having an inclined or arcuate surface for guiding the flow, the inner surface of the chamber is made of a sound absorbing material, and the connection port is a sound absorbing cylinder made of glass wool with a cloth attached to the inner periphery thereof, and the sound absorbing cylinder of the sound absorbing cylinder. The cover member covers the outer circumference and the side surface.

[Operation] In the sound deadening type ventilation grill of the present invention, the sound absorbing tube at the connection port attenuates long wavelength sound from the ventilation duct side, and the wind direction plate does not block the air flowing in and out between the connection port and the opening. The small holes in the wind direction plate lead low frequency noise to the back air layer and attenuate it. Then, the cloth prevents the fibers of the glass wool of the silencer from scattering.

In addition, in another muffler type ventilation grill of the present invention, the sound absorbing tube at the connection port attenuates long wavelength sound from the ventilation duct side, and the wind direction plate does not block the air flowing in and out between the connection port and the opening. The turbulence will be less likely to occur, and the cloth will prevent the fibers of the glass wool of the silencer from scattering.

[Embodiment] FIG. 1 is a front view showing an embodiment of a ventilation device including a sound deadening type ventilation grill according to the present invention, and FIG. 2 is an exploded perspective view showing the structure of the sound deadening type ventilation grill, and FIG. FIG. 4 is an exploded perspective view and a cross-sectional view showing the structure of the connection port of the noise reduction type ventilation grill. In FIG. 1, a muffler type ventilation grill 3 is connected via a ventilation duct 2 to the blow side of a blower 1 attached to the air above the ceiling. The suction side of the blower 1 is connected to an outdoor intake (not shown) via a ventilation duct 2. When the blower 1 is operated, air is sucked in from the outside,
Air is supplied from the noise reduction type ventilation grill 3 to the room by the flow of air as shown by the arrow in the figure (however, the flow of air may be opposite to that in the example in which the air in the room is sucked in and discharged to the outside). The muffler type ventilation grill 3 as a terminal device in the above ventilation device has a connection port 4 connected to the ventilation duct 2 on one side, and a muffler chamber 6 having a grill mounting opening 5 on the lower surface side, and the muffler chamber 6 Grille mounting opening 5
And a grill 7 which is attached to the grill and forms a ventilation hole in the room. The muffling chamber 6 is formed in a box shape with an open lower part of a square shape, and inside the muffle chamber 6, a ventilation flow that flows between the inner opening of the connection port 4 and the grill mounting opening 5 is inserted.
The wind direction plate 8 that guides to the side is obliquely provided substantially parallel to the diagonal line. The wind direction plate 8 is for smoothly changing the wind direction to the grill mounting opening 5 side, and may have an arc shape. A plurality of small holes 9 are formed in the wind direction plate 8 and communicates with a rear air layer 10 having a triangular prism shape formed by the outer wall of the muffling chamber behind the wind direction plate 8. The wind direction plate 8 is provided so as to fill the width of the muffling chamber 6, and an air passage defined by the wind direction plate 8 and the inner surface on the side of the connection port 4 and both inner surfaces is formed in the muffling chamber 6. A sound absorbing material 11 divided into four parts is lined on the inner surface of the ventilation passage as shown in FIG. As shown in FIGS. 3 and 4, the connection port 4 of the muffling chamber 6 has a sound absorbing tube 13 made of glass wool and having an inner surface on the ventilation passage side through which a ventilation flow is pasted with a cloth 12, and this sound absorbing tube.
A cover member 15 that covers the outer periphery of 13 and has an alignment margin 14 in the axial direction, a connection flange 16 for connecting one end side of this cover member 15 to the outside of the muffling chamber 6, and a cover member 15
Pipe 17 for connecting the other end of the to the ventilation duct 2
It consists of and. The opening for connecting the connection port 4 in the outer shell of the muffling chamber 6 is subjected to burring processing as a burring shape portion 18, and the sound absorbing cylinder 13 is fitted into the sound absorbing cylinder 13 by burring. The end surface of the is covered. A pipe flange 19 is attached to the connection pipe 17, and the pipe flange 19
Also, a burring portion 20 is formed so as to cover the end surface of the sound absorbing cylinder 13 on the ventilation duct connection side. In addition, reference numerals in the figure
21 is a fixing metal fitting for mounting and attaching the mounting spring 22 on the grill 7 side,
23 is a screw. Further, the inclination angle of the wind direction plate 8 is optimally 45 ° with respect to the center line of the connection port 4, and the range of 30 ° to 60 ° is the allowable inclination range.

In the muffling chamber 6 having the above configuration, the muffling chamber 6
There is no turbulence in the air flow inside and there is no noise generated by the turbulence in the air flow. Therefore, the silencing chamber 6 itself does not serve as a noise source, and the silencing action of the sound absorbing material 11 and the sound absorbing cylinder 13 directly serves as the noise preventing function of the silencing chamber 6. The sound absorbing material 11 in the sound deadening chamber 6 is difficult to obtain a sufficient thickness and area due to a request from securing an air passage and a restriction from a space of a mounting portion, a size of the grill 7, etc.
In addition, since the sound absorbing cylinder 13 has a sound deadening function, a sufficient sound deadening effect can be achieved without increasing the overall size. In particular, the sound deadening cylinder 13 can attenuate the noise of the blower 1 from the side of the ventilation duct 2 having a long wavelength. It works to attenuate low frequency noise. Therefore, the noise from the blower 1 side can be reduced extremely well. Furthermore, since the inner surface including both ends of the sound absorbing cylinder 13 is structurally covered, the fiber of the glass wool as the base material of the sound absorbing cylinder 13 does not scatter and is hygienic. Note that, as shown in FIG. 5, the wind direction plate 8 and the outer shell of the muffling chamber 6 may be integrated. However, in this case, the rear air layer 10 is not formed. Further, the axial displacement of the sound absorbing cylinder 13 at the time of assembly can be prevented by inserting the screw 23 to the connection flange 16 into the sound absorbing cylinder 13.

[Advantages of the Invention] As described above, according to the sound deadening type ventilation grill of the present invention, the change of the wind direction smoothly progresses in the sound deadening chamber, the noise due to the turbulent flow is not generated, and the back air behind the wind direction plate is not generated. Low-frequency noise can be attenuated by the layer, and the sound absorption function of the sound absorbing cylinder also serves as the sound absorption function of the connection port for connecting with the ventilation duct of the sound deadening chamber.
Moreover, it is possible to prevent the fibers of the glass wool constituting the sound absorbing tube from scattering.

Further, according to another invention, the change of the wind direction in the chamber smoothly progresses, the noise due to turbulence can be reduced, and the noise from the ventilation duct side is also reduced by the sound absorbing cylinder, thereby constructing the sound absorbing cylinder. It is possible to prevent the fibers of the glass wool from scattering.

[Brief description of drawings]

FIG. 1 is a front view of a ventilation device including a sound deadening type ventilation grill according to the present invention, FIG. 2 is an exploded perspective view of a sound deadening chamber, and FIG.
FIG. 4 is an exploded perspective view of the connection port, FIG. 4 is a cross-sectional view of the connection port, FIG. 5 is a cross-sectional view showing another embodiment of the sound deadening chamber, and FIG. 6 is a ventilation including a sound deadening type ventilation grill as a conventional example. FIG. 7 is a front view of the apparatus, and FIG. 7 is a sectional view of a conventional silencing chamber. In the figure, 1 is a blower, 2 is a ventilation duct, 3 is a muffler type ventilation grille, 4 is a connection port, 5 is a grill mounting opening, 6 is a muffling chamber, 7 is a grill, 8 is a wind direction plate, 9 is a hole, 10 Is a rear air layer, 11 is a sound absorbing material, 12 is a cloth, 13 is a sound absorbing cylinder, 15 is a cover member, 16 is a connecting flange, 17 is a connecting pipe, and 18,2
0 is a burring portion. In the figure, the same reference numerals
Indicates the same or corresponding part.

Claims (2)

[Scope of utility model registration request] 1. A chamber which forms a space inside, has a cylindrical connection port for connecting a ventilation duct on one side, and has an opening portion for opening to the room on the other side, and an inner wall of the chamber. , A slanted or arc-shaped wind direction plate that guides the flow of air between the connection port and the opening and forms a rear air layer on the back side, and the air direction plate is provided with a plurality of small holes. , A sound absorbing material is attached to the inner surface of the air passage formed by the air flow direction plate and the inner surface of the chamber, and the connection port is a sound absorbing cylinder made of glass wool with a cloth stuck on the inner circumference, and the outer circumference of the sound absorbing cylinder. And a silencer type ventilation grill comprising a cover member for covering the side surface. 2. A space is formed inside, a cylindrical connection port for connecting a ventilation duct is provided on one side, and an opening portion that opens to the room is provided on the other side, and the connection port and the opening portion are provided. A sound absorbing cylinder made of glass wool having a chamber having an inclined or arcuate surface for guiding the flow of air between the chambers, the inner surface of the chamber being made of a sound absorbing material, and the connection port having a cloth on the inner periphery thereof. And a silencer type ventilation grill comprising a cover member that covers the outer circumference and side surfaces of the sound absorbing cylinder.