JPS582136Y2 - Kaitenden Kinotameno Shyouonsouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a muffling device, and more particularly to a muffling device for a rotating electric machine having a cooling fan.

A conventional silencer for a rotating electrical machine has a structure as shown in FIG.

A fully enclosed external sector electric motor (hereinafter simply referred to as an electric motor) generally indicated by the reference numeral 1 in the figure has a frame 1a and a rotating shaft 1b, and one end of the rotating shaft is supported by an anti-load side bracket 1c via a bearing 1d. , the other end is supported by a load-side bracket 1h via a bearing (not shown).

A plurality of intake openings 1e are formed on the side of the anti-load side bracket 1c, and a portion of the bracket Nc adjacent to the frame 1a forms an exhaust opening 1f.

A cooling fan 1g is attached to the opposite-load side of the rotating shaft 1b, and when the motor 1 rotates, air is sucked in through the intake opening 1e and exhausted through the exhaust opening 1f to cool the motor 1. There is.

The muffler has a cylindrical muffler housing 2 with one end fixed to the anti-load side bracket 1c and the other end fixed to the load side bracket Nh.

A plurality of intake ports 4 are formed on the outer peripheral portion of the housing 2 on the opposite load side, and a plurality of exhaust ports 10 are formed on the end portion on the load side.

The inside of the silencer housing 2 is formed by an intake passage 12 formed by a cylindrical partition plate 5 fixed to the anti-load side bracket Nc and an annular partition plate 6 provided approximately in the longitudinal center of the housing 2.
and an exhaust passage 13.

The intake passage is bent by a longitudinal blocking plate 3, and the exhaust passage 13 is bent by a blocking plate 8 supported by a support plate 9 on the partition plate 5.

A sound absorbing material 11 such as glass wool or rock wool is attached to the above-mentioned casing 2, shielding plate 3, partition plate 6, shielding plate 8, etc.

In the figure, reference numeral 7 indicates a sealing material for blocking the intake passage 12 and the exhaust passage 13.

In the silencer having the above structure, when the electric motor 1 is energized, the cooling fan 1g attached to the rotating shaft 1b rotates, and air is sucked in from the intake port 4 as shown by the arrow and flows through the bent intake passage 12. Since the exhaust passage 13 is complicatedly bent from the intake opening 1e to the cooling fan 1g and from the exhaust opening 1f, the ventilation resistance is large, so the air volume is reduced and the cooling effect of the electric motor 1 is reduced. It's getting worse.

In addition, the structure is complicated, which makes it difficult to work, and the production cost of the device is high.Furthermore, because the structure is mainly composed of bent parts, the silencing effect is biased towards extremely high frequencies, making it difficult to effectively silence the sound. It has disadvantages such as not being able to obtain

SUMMARY OF THE INVENTION The object of the present invention is to eliminate the above-mentioned drawbacks and to provide a sound damping device that has a simple structure and is capable of effective cooling and sound damping.

According to the present invention, in a silencer for a rotating electrical machine having a cooling fan attached to one end thereof, the noise reduction device is provided coaxially with the rotating electrical machine and outside the rotating electrical machine to form an air passage between the rotating electrical machine and the rotating electrical machine. a muffler casing, which is provided coaxially with the rotary electric machine between the rotary electric machine and the muffler casing to divide the air passage into an intake passage and an exhaust passage; There is obtained a sound damping device for a rotating electric machine, characterized in that it has a partition plate extending over almost the entire length of the air passage, and a sound absorbing material attached to at least a part of the air passage.

Next, a preferred embodiment of the present invention will be described with reference to FIGS. 2a and 2b.

In the illustrated embodiment, a muffler housing 2 is provided, one end of which is coupled to the anti-load side bracket 1c of the electric motor 1, and the other end coupled to the load side bracket Nh.

Inlet ports 4 are formed at two axially symmetrical positions on the outer periphery of the silencer housing 2 near the end on the load side, and two air intake ports 4 are formed on the outer periphery near the end on the anti-load side in the circumferential direction. The exhaust port 10 is formed at an angle of 90 degrees.

Inside the silencer housing 2, a cylindrical partition plate 5 is provided coaxially with the electric motor 1 and extending over almost the entire length of the electric motor 1, and the air passage formed by the electric motor 1 and the housing 2 is defined as an outer passage. It is divided into an inner passage.

This outer passage is further divided into four by a radial partition plate 6a provided between the partition plate 5 and the housing 2,
Annular partition plates 6C and 6b are provided on the load side and anti-load side, respectively.
is provided.

In this way, the partition plate 6b defines an annular intake chamber 14, and the partition plate 6C defines an annular exhaust chamber 15.

The partition plate 6b has an opening A only in the portion facing the intake passage 12 communicating with the intake port 4, and the partition plate 6c has an opening B only in the portion facing the exhaust passage 13 communicating with the exhaust port 10.

A sound absorbing material is attached to the outer periphery of the partition wall plate 5, as indicated by reference numeral 11.

In the silencer of the present invention having the above structure, when the electric motor 1 is energized, the cooling fan rotates, and the outside air is forcibly sucked in through the two intake holes 4 provided axially symmetrically, and the respective ventilation They pass through the passage 12, pass through the opening A of the partition plate 6b, and merge in the annular intake chamber 14.

The air in the intake chamber 14 is sent to the exhaust chamber 15 through an inner passage by a cooling fan while cooling the outer peripheral surface of the electric motor 1.
The air is discharged from the opening B through the exhaust passage 13 formed by the partition plate 5 and the casing 2, and from the exhaust port 10.

The aerodynamic noise or electromagnetic noise of the cooling fan is caused by the intake passage 12,
Although the sound is radiated to the atmosphere from the intake port 4 and the exhaust port 10 through the exhaust passage 13, the sound is effectively absorbed by the sound absorbing material 11 provided in the sound propagation path, and the noise of the electric motor is effectively prevented. Ru.

As described above, in the silencer according to the present invention, the main parts constituting the silencer are linear, so the ventilation resistance is small, so the cooling effect of the electric motor is excellent, and the air flow inside the silencer is also improved. There is less turbulence and the aerodynamic noise generated inside this muffler is also suppressed.

Furthermore, the structure is extremely simple, thus reducing manufacturing costs.

Furthermore, the noise reduction device according to the present invention has the effect of not being biased toward high frequencies.

Next, another embodiment of the present invention will be described with reference to FIG.

In this embodiment, the sound absorbing material 11 is attached not only to the partition wall plate 5 but also to the inner surface of the muffler housing 2, so that an even greater sound damping effect can be obtained.

In the above embodiment, the air passage is divided into four parts, but it can be divided into more parts if necessary, and the casing can be attached to the electric motor via rubber or the like.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a rotating electric machine having a noise reduction device according to the prior art, FIGS. 2a and 2b show a preferred embodiment of the present invention, and FIG. 2a is a cross-sectional view taken along line II in FIG. 2b. Figure 2b is a sectional view taken along line ■-■ in Figure 2a,
FIG. 3 is a sectional view showing another embodiment of the present invention. The same reference numerals indicate the same or equivalent parts throughout the drawings;
1 is an electric motor, 1a is a frame, 1b is a rotating shaft, 1C is a bracket, 1d is a bearing, 1e is an intake opening, 1f is an exhaust opening, 1g is a cooling fan, 1h is a bracket, 2 is a silencer housing, 3 is a shielding plate, 4 is an intake port, 5 is a partition plate, 6.6a, 6
b, 6C is a partition plate, 7 is a seal, 8 is a shielding plate, 9 is a support plate, 10 is an exhaust port, 11 is a sound absorbing material, 12 is an intake passage, 1
3 is an exhaust passage, 14 is an intake chamber, and 15 is an exhaust chamber.

Claims (1)

[Scope of utility model registration request] It has a frame body and a rotating shaft, one end of the rotating shaft is supported by the anti-load side bracket via a bearing, the other end of the rotating shaft is supported by the load side bracket via the bearing, and one end of the rotating shaft is supported by the load side bracket via the bearing. A silencer for a rotating electric machine equipped with a cooling fan, the upper end of which is connected to the anti-load side bracket,
Its lower end is connected to the load side bracket, and it is formed into a cylinder with a U-shaped cross section, and is provided with an intake port at a lower position facing each other, and an exhaust port at an upper position facing each other, substantially orthogonal to the space between the intake ports. a partition plate provided between the inner wall of the case and the frame body and equipped with a sound absorbing material; an air intake chamber formed in the upper part of the case and connected to the partition plate; a first annular partition plate; a second annular partition plate that is connected to the lower end of the partition plate and forms an exhaust chamber in the lower part of the casing; and a second partition plate formed between the partition plate and the inner wall of the casing. a third partition plate for vertically dividing the air passage into four parts so that an exhaust port and an intake port provided in the casing do not enter into the same partition; A first opening is provided in the first partition plate that is in contact with an air passageway in which an intake port is provided in the casing, and a second opening is provided in the second partition plate that is in contact with an air passageway in which an exhaust port is provided in the casing. 1. A silencer for a rotating electric machine, characterized in that air introduced from the intake port is provided with an opening so that air introduced from the intake port passes through the outer surface of the frame body and is discharged from the discharge port.