JP3734519B2 - Fan with silence box - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a fan with a sound deadening box, which includes a sound deadening box, and which silences noise generated from a sound source such as a fan.
[0002]
[Prior art]
Conventionally, this type of fan with a sound deadening box has a structure that absorbs sound from the fan by installing a plate-like sound absorbing material inside the sound deadening box, and prevents swirling to prevent air vortex and swirling through the sound deadening box. A structure that attaches a plate and a wind direction change plate is adopted.
[0003]
[Problems to be solved by the invention]
However, in the fan with a silencer box having the above-mentioned conventional structure, the cross-sectional area or cross-sectional shape of the passage through which air passes from the suction port of the silencer box to the suction port of the fan suddenly increases between the suction port and the suction port of the fan. Because there is a change, vortex may occur in the air flow flowing through the passage, the pressure loss in the silencer box due to this vortex is large, the performance of the fan deteriorates due to the swirling flow of air, and noise is generated due to the vortex was there. In addition, there is a problem that sound emitted from the fan leaks to the outside through the passage and becomes noise.
[0004]
The present invention has been made in view of the above points, eliminates the above-mentioned problems, does not generate air vortices or swirling flows in the air passage of the muffler box, reduces the fan performance, and reduces the fan performance. An object of the present invention is to provide a fan with a sound deadening box in which noise generated from a sound source such as the above does not leak to the outside.
[0005]
[Means for Solving the Problems]
The present invention for solving the above problems, a silencer box (1), comprising a fan (2) provided in the digestion sound box (1) in, sucked from the suction port of the muffler box (1) (3a) air guided to the suction port of the digestion sound box (1) the fan through the formed passages (6) in (2) (2a), the discharge port of the fan pressurized with (2), silencer box (1) In the fan with a sound deadening box configured to discharge from (4a) , the sound absorbing material (5) connects the passage (6) from the air inlet (3a) of the sound deadening box (1 ) to the air inlet (2a) of the fan (2 ). And at least two offset portions (6a, 6c) and the offset portions (6a, 6c) from the suction port (3a ) of the silencer box (1) to the suction port (2a) of the fan (2). ) To communicate with each other at the communicating portion (6b). Communicated with the Katayose portion (6a) and Katayose portion (6c) is a predetermined amount not biased in opposite directions from the center line (l1, l2) of the center line of the silencer box (1) (L), Katayose portion (6a, 6c) and the communication part (6b) are substantially the same in cross-sectional area and cross-sectional shape so that vortices and swirling flows do not occur in the air flow passing through the passage (6) .
[0006]
Further, the present invention is characterized in that a reflection plate that reflects sound transmitted through the sound absorbing material (5) to the sound source side is provided at a predetermined position in the sound absorbing material (5) of the silencer box (1).
[0007]
Further, the present invention is characterized in that a reflecting plate is provided at a boundary portion (F, G) between the offset portion (6a, 6c) and the communicating portion (6b) in the sound absorbing material (5) of the silencer box (1) .
[0009]
[Action]
Since the present invention forms the passage from the suction port of the muffler box to the suction port of the fan as described above so that the cross-sectional area and the cross-sectional shape thereof are not substantially changed from the suction port to the suction port of the fan, There is no vortex of the air flow in the passage, the pressure loss in the silencer box can be reduced, the performance of the fan is prevented from being lowered by the swirling flow of air, and no noise is generated.
[0010]
Further, since the passage from the suction port of the muffler box to the suction port of the fan is formed by the sound absorbing material, the sound generated when air passes through the passage, the sound generated from the fan, and the like are absorbed by the sound absorbing material.
[0011]
Further, since the passage of the fan is offset from the center line of the silencer box in at least two places so that the sound of the fan is not directly transmitted to the suction port of the silencer box, the sound from the fan is the offset part and it. Since it hits the inner surface of the passage of the connecting portion and is absorbed here, it does not propagate directly to the inlet.
[0012]
In addition, since the reflection plate that reflects the sound that passes through the sound absorbing material is provided in the silencer box, the sound that passes through the sound absorbing material from the sound source and reaches the reflecting plate is reflected by the reflecting plate toward the sound source side. The effect is further improved.
[0013]
【Example】
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing the structure of a fan with a sound deadening box according to the present invention. In FIG. 1, reference numeral 1 denotes a silencer box body, and a fan 2 is provided in the silencer box 1.
[0014]
The muffler box 1 has a suction plate 3 and a discharge plate 4 at both ends. The suction plate 3 is provided with a suction port 3a, and the discharge plate 4 is provided with a discharge port 4a. Inside the sound deadening box 1, an air passage 6 is provided by a sound absorbing material 5 from the suction port 3a to the discharge port 4a. The fan 2 is provided in the vicinity of the discharge port 4 a of the passage 6.
[0015]
The fan 2 includes an electric motor 8 and an impeller 9. The impeller 9 is fixed to a main shaft 8 a of the electric motor 8 and is disposed in a casing 7 provided in the air passage 6. The air passage 6 from the suction port 3a to the suction port 2a of the fan 2 has its center lines l1 and l2 at the portion 6a of the suction plate 3 approaching the suction port 3a and the portion 6c of the fan 2 approaching the suction port 2a. Are arranged so as to be offset from the center line L of the muffler box on the opposite sides, and the portion 6a and the portion 6c are connected by a portion 6b.
[0016]
Here, the cross section of the suction port 3a of the suction plate 3 communicating with the air passage 6 is A, the cross section of the portion 6a of the passage 6 is B, the cross section of the portion 6b of the passage 6 is C, and the cross section of the portion 6c of the passage 6 is D, if the cross section of the suction port 2a of the fan 2 is E, the areas and shapes of the cross sections A, B, C, D, E are substantially the same, that is, the cross-sectional area and the cross-sectional shape of the passage are from the suction port 3a. The fan suction port 2a is formed so that there is no sudden change.
[0017]
Further, reflecting plates 10 and 11 such as iron plates are provided at the boundary portion F between the portions 6a and 6b of the passage 6 and the boundary portion G between the portions 6b and 6c of the passage 6. In addition, 12 and 13 in FIG. 1 show the companion flanges at the suction port side and the discharge port side, respectively.
[0018]
In the fan with the sound deadening box having the above structure, when the motor 8 is started and the fan 2 is started, the impeller 9 rotates, and the air sucked from the suction port 3a of the sound deadening box 1 is part 6a, 6b, 6c of the passage 6. Through the suction port 2a and the discharge port 2b of the fan 2, and is sent out from the discharge port 4a of the muffler box 1.
[0019]
At this time, as described above, the areas and shapes of the cross sections A, B, C, D, and E of the passage 6 are substantially the same, that is, the cross sectional area and the cross sectional shape of the passage are changed from the suction port 3a to the fan suction port 2a. Therefore, the airflow passing through the passage does not generate vortex or swirling flow, the pressure loss of the muffler box 1 can be reduced, and the performance of the fan 2 is reduced due to swirling. It can be prevented and vortex noise generated by the vortex is eliminated.
[0020]
Moreover, although noise which makes the impeller 9 of the fan 2 a sound source is radiated | emitted from the inlet 2a of the fan 2 as shown by the arrow H of FIG. 2, they are the inner wall surfaces of the part 6c of the channel | path 6 which consists of the sound-absorbing material 5. Is further absorbed, and the sound is absorbed by the inner wall surfaces of the portions 6b and 6a of the passage 6, so that the noise from the suction port 3a of the muffler box 1 is greatly reduced.
[0021]
Further, as described above, the air passage 6 from the suction port 3a to the suction port 2a of the fan 2 has its center lines l1 and l2 silenced at the portion 6a approaching the suction port 3a and the portion 6c close to the suction port 2a. Since they are arranged so as to be offset from each other so as to be opposite to the center line L of the box 1, the noise propagating from the impeller 9 of the fan 2 in the direction of the suction port 3 a is caused by the parts 6 a and 6 c of the passage 6. Since it is blocked by the inner wall surface of the portion 6b that connects the two, it does not propagate directly to the suction port 3a.
[0022]
Reflecting plates 10 and 11 that reflect sound waves that have penetrated the sound absorbing material 5 through the boundary portion F of the passage 6 of the sound deadening box 1 and the boundary portion G of the passage 6 and the boundary portion G of the portion 6b and the portion 6c , for example, an iron plate Therefore, the noise that has penetrated through the sound absorbing material 5 is reflected to the noise source side by the reflectors 10 and 11, and is absorbed by the sound absorbing material.
[0023]
The structure of the fan with the sound deadening box is an example, and the fan with the sound deadening box of the present invention is not limited to this. In short, the passage 6 from the air inlet 3a to the air inlet 2a of the fan is cut off. The area and the cross-sectional shape may be substantially the same so that there is no sudden change from the inlet to the inlet of the fan, and the passage may be formed of a sound absorbing material. In addition, the shape of the passage is also shown if the passage is offset from the center line of the silencer box to the opposite side at least at two places so that the sound from the fan 2 is not directly transmitted to the suction port 3a of the silencer box. It is not limited to the shape as shown in FIG.
[0024]
Further, the reflectors 10 and 11 provided in the sound deadening box 1 are not limited to the boundary portion F between the portion 6a and the portion 6b and the boundary portion G between the portion 6b and the portion 6c as described above. What is necessary is just to arrange | position in the position which can reflect the sound which permeate | transmits the sound-absorbing material 5 to the sound source side effectively.
[0025]
【The invention's effect】
As described above, according to the present invention, the following effects (1) to (4) interact with each other to provide a fan with a sound deadening box that can greatly reduce noise without deteriorating the performance of the fan. it can.
(1) The cross-sectional areas and cross-sectional shapes of the offset portions (6a, 6c) and the communication portion (6b) constituting the passage (6) are substantially set so that vortices and swirling flows do not occur in the air flow passing through the passage (6). Since they are the same, air flow vortices are not generated in the passage (6) , the pressure loss of the silencer box (1) can be reduced, and the performance of the fan (2) can be prevented from being degraded due to the swirling of the air flow. There is no noise generated by eddy currents.
[0026]
(2) Since the passage (6) from the suction port (3a ) of the silencer box (1) to the suction port (2a) of the fan (2 ) is formed by the sound absorbing material (5) , air passes through the passage (6) . The sound generated when passing and the sound generated from the fan are absorbed by the sound absorbing material (5) , and noise can be reduced.
[0027]
(3) The passage from the suction port (3a ) of the silencer box (1) to the suction port (2a) of the fan (2) includes at least two offset portions (6a, 6c) and the offset portions (6a, 6c). The communicating portion (6b) is a communicating portion (6b), and the offset portion (6a) and the offset portion (6c) communicated with each other at the communicating portion (6b) have their center lines (l1, l2) as the center line (L since was biased to a predetermined amount each other opposite direction from) the sound of the fan (2) is particularly impinges on the inner surface of Katayose portion (6a, 6c) communicating portion for communicating the (6b), from where it is sound-absorbing, It does not propagate directly to the suction port (3a ) of the silencer box (1), and noise from the suction port (3a) can be reduced.
[0028]
(4) Further, Katayose unit (6a, 6c) and the communicating portion boundary portion (6b) (F, G) reflector for reflecting the sound propagating transmitted through the sound absorbing material (5) in a (10, 11) Since the sound that has passed through the sound absorbing material (5) from the sound source and reaches the reflecting plate is reflected to the sound source side by the reflecting plate (10, 11), the silencing action is further improved and noise can be reduced. it can.
[Brief description of the drawings]
FIG. 1 is a diagram showing a structure of a fan with a sound deadening box according to the present invention.
FIG. 2 is a diagram for explaining a silencing effect of the fan with a silencing box of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Silence box 2 Fan 3 Suction plate 4 Discharge plate 5 Sound absorption material 6 Passage 7 Casing 8 Electric motor 9 Impeller 10 Reflection plate 11 Reflection plate 12 Companion flange 13 Complement flange

Claims (3)

A silencer box (1), comprising a fan (2) provided in the digestion sound box (1) in, digested sound box (1) of the suction opening (3a) from sucked digestion sound box (1) in the air Through the passage (6) formed on the fan (2) to the suction port (2a) of the fan (2) , pressurized by the fan (2) , and discharged from the discharge port (4a ) of the silencer box (1) In the configured fan with silence box,
Inlet of the fan from the inlet (3a) (2) a (2a) to the passage (6) while forming sound absorbing material (5) of the silencer box (1), inlet of digestion sound box (1) The passage from (3a) to the suction port (2a) of the fan (2) has at least two offset portions (6a, 6c) and a communication portion (6b) communicating the offset portions (6a, 6c). The offset portions (6a) and the offset portions (6c) communicated with each other at the portion (6b) have their center lines (l1, l2) offset in a direction opposite to each other by a predetermined amount from the center line (L) of the silencer box (1). The cross-sectional area and the cross-sectional shape of the offset portions (6a, 6c) and the communication portion (6b) are substantially the same so that vortices and swirling flows do not occur in the air flow passing through the passage (6). A fan with a silencer box. The fan with a sound deadening box according to claim 1,
With a muffler box, characterized in that a reflector that reflects the sound transmitted through the sound absorber (5) to the sound source side is provided at a predetermined position in the sound absorber (5) of the muffler box (1). fan. The fan with a sound deadening box according to claim 2,
The muffler box, wherein the reflector is provided at a boundary part (F, G) between the offset part (6a, 6c) and the communication part (6b) in the sound absorbing material (5) of the muffler box (1). With fan.

Images