JP2682545B2 - Low noise electric blower - Google Patents
Low noise electric blowerInfo
- Publication number
- JP2682545B2 JP2682545B2 JP63325273A JP32527388A JP2682545B2 JP 2682545 B2 JP2682545 B2 JP 2682545B2 JP 63325273 A JP63325273 A JP 63325273A JP 32527388 A JP32527388 A JP 32527388A JP 2682545 B2 JP2682545 B2 JP 2682545B2
- Authority
- JP
- Japan
- Prior art keywords
- layer
- electric blower
- solid solution
- sound absorbing
- blade
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Description
【発明の詳細な説明】 ［産業上の利用分野］ この発明は、低騒音電動送風機に係り、特に電動機の
フレームおよび回転翼車の各羽根に対する低騒音対策に
関するものである。Description: TECHNICAL FIELD The present invention relates to a low-noise electric blower, and more particularly to a low-noise countermeasure for a frame of an electric motor and each blade of a rotary impeller.
［従来の技術］ 第10図は従来の電気掃除機用電動送風機であり、図に
おいて（５）は電動機のステータ、（６）はロータ、
（１）はこれらを内部に支持するフレーム、（４）はブ
ラケット、（７）は上記ロータ（６）に直結された翼
車、（８）はこの翼車を覆うファンケース、（９）は上
記翼車（７）による強制空気流を電動機の冷却のために
上記フレーム内に導く案内羽根である。特に図示した上
記の電動送風機は電動機が整流子電動機であり、翼車
（７）は２ないし４万RPMという高い回転数で回転する
ため、翼車の出口での流速も100数十m/sないし200m/sに
も達し、案内羽根（９）内で流れが静圧変換されて減速
されたとしても、冷却のために導かれた空気流は電動機
内で、第10図のXI−XIの断面を示す第11図のようにフレ
ーム（１）内にあるステータ（５）、ロータ（６）に遮
られ、通風断面としては図中のA.B.Cの限られた部分し
か通過することができず、フレーム（１）内の流れも数
十m/sないし100数十m/s前後で複雑な流れとなる。この
ため圧力変動の激しい翼車（７）付近やフレーム（１）
内で発生する流体騒音は、第10図の排気口（10）からそ
のまま電動機外部に放出されるため非常に大きい騒音レ
ベルとなる。よって吸音材（15）を内張りした遮音ケー
ス（16）でフレーム（１）を覆って低騒音化を図ってい
た。[Prior Art] FIG. 10 shows a conventional electric blower for an electric vacuum cleaner. In the figure, (5) is a stator of the electric motor, (6) is a rotor,
(1) is a frame for supporting these inside, (4) is a bracket, (7) is an impeller directly connected to the rotor (6), (8) is a fan case covering this impeller, and (9) is Guide vanes that guide the forced airflow by the impeller (7) into the frame for cooling the electric motor. Particularly, in the electric blower shown above, the electric motor is a commutator motor, and the impeller (7) rotates at a high rotational speed of 20,000 to 40,000 RPM, so the flow velocity at the exit of the impeller is 100 tens m / s. Even if it reaches up to 200 m / s and the flow in the guide vane (9) is converted into static pressure and decelerated, the air flow guided for cooling is in the electric motor, As shown in FIG. 11 showing a cross section, the stator (5) and the rotor (6) in the frame (1) block the air flow and only a limited portion of ABC in the drawing can pass through. The flow in the frame (1) is also around tens of m / s to 100 tens of m / s, which is a complicated flow. For this reason, there are many pressure fluctuations near the impeller (7) and the frame (1).
Since the fluid noise generated inside is discharged to the outside of the motor as it is from the exhaust port (10) in FIG. 10, it has a very high noise level. Therefore, the frame (1) was covered with a sound insulation case (16) lined with a sound absorbing material (15) to reduce noise.
［発明が解決しようとする課題］ 従来の電動送風機は以上のように構成されているの
で、低騒音化のために吸音材や遮音ケース等の別部材の
付加が必要となり、その分構造が複雑になりまた全体が
大形になる等の問題点があった。[Problems to be Solved by the Invention] Since the conventional electric blower is configured as described above, it is necessary to add another member such as a sound-absorbing material or a sound-insulating case to reduce noise, and the structure is complicated accordingly. However, there was a problem that the whole became large.
この発明は上記の問題点を解消するためになされたも
ので、電動送風機翼車の各羽根自身に空力性能を損なう
ことなく所望の強度と良好な吸音作用を持たせることを
目的とする。The present invention has been made in order to solve the above problems, and an object thereof is to give each blade of an electric blower impeller a desired strength and a good sound absorbing action without impairing aerodynamic performance.
［課題を解決するための手段］ この発明に係る電動送風機の回転する各羽根（12）
は、それの回転時の空気に対する圧力面側を形成する、
合成樹脂の発泡成形法または樹脂や金属、セラミックス
の粒体の焼結成形法で形成した、連通する空孔をもつ多
孔質で吸音効果の高い吸音層（２）と、負圧面側を形成
する、この吸音層の表面部を溶融して非通気性とした固
溶層（３）とを一体に有する面状の２層部材で構成され
ている。[Means for Solving the Problems] Rotating blades (12) of the electric blower according to the present invention
Forms the pressure side for the air during its rotation,
Form a porous sound-absorbing layer (2) with communicating pores and a high sound-absorbing effect (2), which is formed by foam molding of synthetic resin or sintering of resin, metal, or ceramics granules. The sound absorbing layer is composed of a planar two-layer member integrally having a solid solution layer (3) which is made impermeable by melting the surface portion of the sound absorbing layer.
［作用］ この発明の場合は、固溶層で空気もれ防止とその強度
をもたせながら吸音層に良好な吸音作用をもたせてい
る。[Operation] In the case of the present invention, the solid solution layer prevents the air from leaking and has strength, while the sound absorbing layer has a good sound absorbing function.
［実施例］ 第１図はこの発明におけるフレーム（１）と翼車の各
羽根（14）の構成材料を説明するための部分拡大断面図
であり、図中の（２）は上記の吸音層、（３）はその外
側面に形成された上記の非通気性の固溶層でこれらは２
層部材に一体に構成されている。第２図は合成樹脂の発
泡成形法や焼結成形法にて上記の吸音層（２）を形成す
る場合で、（13）は成形金形であり、成形後後の内部は
連通する空孔を有する多孔質の吸音層（２）となり、そ
して上記成形金形（13）に接した外表面は溶融されて非
通気性の固溶層（３）となる。[Embodiment] FIG. 1 is a partially enlarged sectional view for explaining constituent materials of a frame (1) and each blade (14) of an impeller according to the present invention, and (2) in the figure shows the above sound absorbing layer. , (3) is the above-mentioned non-breathable solid solution layer formed on the outer surface thereof, and these are 2
It is formed integrally with the layer member. Fig. 2 shows the case where the above sound absorbing layer (2) is formed by the synthetic resin foam molding method or the sintering molding method, and (13) is a molding die, and the inside after the molding is a communicating hole. And the outer surface in contact with the molding die (13) is melted to form an impermeable solid solution layer (3).
したがってその後この固溶層の所要の一面を図示のよ
うに例えば剥離エッチング、切削等によって除去して該
部に図示のように吸音層（２）を露出させて２層部材を
構成するものである。また第３図の場合は金属、セラミ
ックス等の粒体の焼結成形法で吸音層（２）を形成する
場合で、（13）は成形金形であり成形後の全体としては
多孔質で連通する空孔があるものになる。したがってそ
の後に所要表面部のみを加熱溶融させて該部に図示のよ
うに所望肉厚の固溶層（３）を形成させて同様の２層部
材を構成するものである。Therefore, after that, a required one surface of the solid solution layer is removed by, for example, peeling etching, cutting or the like as shown in the figure, and the sound absorbing layer (2) is exposed in the portion as shown in the figure to form a two-layer member. . In the case of FIG. 3, the sound absorbing layer (2) is formed by the sintering forming method of particles of metal, ceramics, etc., and (13) is a molding die, which is porous as a whole and communicates with each other. There will be holes to do. Therefore, after that, only the required surface portion is heated and melted to form a solid solution layer (3) having a desired thickness on the portion as shown in the figure to form a similar two-layer member.
以上のようにこの発明では周知の発泡成形法（化学的
やガス注入による射出成形法等）や焼結成形法により、
連通する空孔をもつ多孔質の吸音層（２）と非通気性の
固溶層（３）との一体構成品から成る上記の２層部材で
回転する羽根（12）を構成するものである。As described above, according to the present invention, the well-known foam molding method (injection molding method such as chemical or gas injection) or the sintering molding method is used.
The rotating blade (12) is constituted by the above-mentioned two-layer member which is an integrated component of a porous sound absorbing layer (2) having communicating pores and an impermeable solid solution layer (3). .
第４図は上記構成に成る２層部材を電気掃除機用電動
送風機に実施した具体例であり、第５図は第４図のＶ−
Ｖの断面図であり、第10図の従来例と同一または相当部
分には同一符号を付してその重複説明は省略することに
するが、図示のように上記した２層部材から成るフレー
ム（１）が使用されている点に特徴がある。FIG. 4 is a specific example in which the two-layer member having the above-described structure is applied to an electric blower for an electric vacuum cleaner, and FIG. 5 is a V- of FIG.
FIG. 11 is a cross-sectional view of V, in which the same or corresponding portions as those in the conventional example of FIG. It is characterized in that 1) is used.
具体的には外側面の固溶層（３）はフレーム（１）内
から外表面への空気のもれを完全に防止するため、電動
機内部の冷却効果を損なうことはない。またフレーム
（１）の内側面に形成された吸音層（２）は、流体騒音
に対して高い吸音作用が得られる連通する空孔をもつ多
孔質の吸音層に選定できるため、高い吸音作用が得られ
る。また副次的な効果として、電動機の回転に伴う振動
も、フレーム（１）を上記の２層部材で構成したため、
これにより振動減衰効果も同時に得られ、電動送風機全
体への振動伝達が非常に小さくなって全体としての振動
騒音の発生が抑えられる効果もある。Specifically, the solid solution layer (3) on the outer surface completely prevents the leakage of air from the inside of the frame (1) to the outer surface, so that the cooling effect inside the electric motor is not impaired. Further, since the sound absorbing layer (2) formed on the inner surface of the frame (1) can be selected as a porous sound absorbing layer having communicating pores that can obtain a high sound absorbing action against fluid noise, a high sound absorbing action can be obtained. can get. Further, as a side effect, since the frame (1) is composed of the above-mentioned two-layer member, the vibration accompanying the rotation of the electric motor is also
As a result, a vibration damping effect can be obtained at the same time, and the vibration transmission to the entire electric blower can be made extremely small, so that the generation of vibration noise as a whole can be suppressed.
その他フレームとしての部品の強度的な面では、完全
な多孔質体に比べると上記の固溶層（３）を有する分だ
け強度は高く、かつこの強度は固溶層の肉厚の増加によ
りさらに強化でき、またその調整も簡単にできる。In terms of strength of other parts as a frame, the strength is higher than that of a completely porous body by the presence of the solid solution layer (3), and this strength is further increased by increasing the thickness of the solid solution layer. It can be strengthened and easily adjusted.
次に第６図は上記２層部材をシロッコファンの翼車
（11）における各羽根（14）に実施したこの発明の一実
施例を示す斜視図であり、第７図は第６図の各羽根（1
4）の動作特性を示す拡大水平断面図である。この実施
例では、翼車（11）の回転時の空気に対する各羽根（1
4）の圧力面側に連通する空孔を得るため、該部を合成
樹脂粒にて焼結成形した連通する空孔をもつ多孔質の吸
音層（２）に形成すると共に、負圧面側はその表面部の
溶融により非通気性の固溶層（３）に形成しているもの
である。これにより翼車（11）に回転に際しては第７図
のように高い空力性能と上記同様の良好な吸音効果が得
られる低騒音の電動送風機が得られる。Next, FIG. 6 is a perspective view showing an embodiment of the present invention in which the above-mentioned two-layer member is applied to each blade (14) of a sirocco fan impeller (11), and FIG. Feather (1
FIG. 4 is an enlarged horizontal sectional view showing the operation characteristics of 4). In this embodiment, each blade (1
In order to obtain pores communicating with the pressure surface side of 4), the portion is formed into a porous sound absorbing layer (2) having pores communicating with each other, which is formed by sintering with synthetic resin particles, and the negative pressure surface side is formed. The surface portion is melted to form an air-impermeable solid solution layer (3). As a result, when rotating the impeller (11), a low-noise electric blower can be obtained which has high aerodynamic performance as shown in FIG. 7 and good sound absorbing effect similar to the above.
なお、この際の吸音層（２）を合成樹脂の発泡成形法
あるいは金属、セラミックスの粒体による焼結成形法に
よって上記のように構成してもよい。The sound absorbing layer (2) at this time may be configured as described above by a foam molding method of synthetic resin or a sintering molding method using particles of metal or ceramics.
したがってこの発明のものでは負圧面側の固溶層
（３）は、それぞれの羽根を通り抜ける空気の流れを完
全に防止するため、吸音層の空孔率の影響を受けること
なく良好な空力性能を維持することが可能となり、また
圧力変動の激しい各羽根（14）の圧力面側に位置する吸
音層（２）は、高い吸音作用が得られる連通する空孔を
もつ多孔質の吸音層に選定できるため、所望の高い吸音
作用が得られる。その他各羽根（14）の強度は生成され
る固溶層（３）の肉厚の所望の調整により簡単に制御で
きる。Therefore, in the case of the present invention, the solid solution layer (3) on the suction surface side completely prevents the flow of air passing through each blade, so that good aerodynamic performance is obtained without being affected by the porosity of the sound absorbing layer. The sound absorbing layer (2) that can be maintained and is located on the pressure surface side of each blade (14) where the pressure fluctuates drastically is selected as a porous sound absorbing layer having communicating pores that provides a high sound absorbing effect. Therefore, a desired high sound absorbing effect can be obtained. The strength of each blade (14) can be easily controlled by adjusting the thickness of the solid solution layer (3) to be produced.
さらに第８図、第９図はこの発明の他の実施例とし
て、軸流送風機（12）の各羽根（14）に上記構成の２層
部材を応用した例を示す斜視図と羽根の断面図であり、
上記実施例と同様、第９図に示す圧力面側に、連通する
空孔をもつ多孔質の吸音層（２）を、負圧面側に非通気
性の固溶層（３）を形成させている点に特徴があり、そ
の他は第６図の場合と同様である。Further, FIGS. 8 and 9 are perspective views and cross-sectional views of blades, showing another example of the present invention, in which the two-layer member having the above-described structure is applied to each blade (14) of an axial blower (12). And
Similar to the above embodiment, a porous sound absorbing layer (2) having communicating pores is formed on the pressure surface side shown in FIG. 9, and an air-impermeable solid solution layer (3) is formed on the suction surface side. The other points are the same as in the case of FIG.
なお羽根に多孔質材を使用するものとしては実開昭63
−32196号公報に示されたものがあるが、この場合は送
風機の空力性能を維持させるために吸音性能を犠牲にし
たり、逆に高い吸音効果を得るために空孔率を大きくし
て空力性能を低下させるもので、この発明のものと構
成、作用効果を全く異にするものである。In addition, as for using a porous material for the blade, Shokai Sho 63
-32196 is disclosed, but in this case, the aerodynamic performance is sacrificed to maintain the aerodynamic performance of the blower, or conversely, the porosity is increased to obtain a high sound absorbing effect. The present invention is completely different from that of the present invention in structure, function and effect.
［発明の効果］ この発明の低騒音電動送風機における回転する羽根
は、以上のように構成された２層部材で構成されている
ので、羽根自体に高い吸音作用をもたせることができ、
別個の吸音材や遮音ケースの付設の必要がなく、また吸
音性能を犠牲にすることなく、強度が大きく高い空力性
能の回転する羽根を有する低騒音電動送風機が簡単にし
てかつ安価に提供できるという効果がある。[Advantages of the Invention] Since the rotating blade in the low-noise electric blower of the present invention is composed of the two-layer member configured as described above, the blade itself can have a high sound absorbing effect,
It is said that a low-noise electric blower having rotating blades with high strength and high aerodynamic performance can be provided easily and at low cost without the need to attach a separate sound absorbing material or sound insulating case and without sacrificing sound absorbing performance. effective.
第１図はこの発明の低騒音電動送風機における回転する
羽根に使用される２層部材の部分断面図、第２図および
第３図は上記２層部材の構成手段を模式的に示すプロセ
ス図、第４図および第５図は２層部材を電気掃除機用電
動送風機に実施した具体例を示す垂直断面図およびその
第４図のＶ−Ｖ断面図、第６図および第７図はこの発明
の一実施例を示すシロッコファンの斜視図および空力特
性図、第８図および第９図はこの発明の他の実施例を示
す斜視図および空力特性図、第10および第11図は従来の
電気掃除機用電動送風機を示す垂直断面図および第10図
のXI−XI断面図である。 なお図中（１）はフレーム、（２）は吸音層、（３）は
固溶層、（11）は翼車、（14）は羽根である。 その他図中同一符号は同一または相当部分を示すものと
する。FIG. 1 is a partial cross-sectional view of a two-layer member used for a rotating blade in a low-noise electric blower of the present invention, and FIGS. 2 and 3 are process diagrams schematically showing the constituent means of the above-mentioned two-layer member. FIGS. 4 and 5 are vertical sectional views showing a specific example in which a two-layer member is applied to an electric blower for an electric vacuum cleaner, and VV sectional views of FIG. 4, FIG. 6 and FIG. FIG. 8 is a perspective view of a sirocco fan showing an embodiment of the present invention, and FIGS. 8 and 9 are perspective views showing the other embodiments of the present invention. FIG. 10 and FIG. FIG. 11 is a vertical sectional view showing the electric blower for the vacuum cleaner and a sectional view taken along line XI-XI of FIG. 10. In the figure, (1) is a frame, (2) is a sound absorbing layer, (3) is a solid solution layer, (11) is an impeller, and (14) is a blade. The same reference numerals in the drawings denote the same or corresponding parts.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 今井 智久 埼玉県大里郡花園町大字小前田1728番地 １ 三菱電機ホーム機器株式会社内 (56)参考文献 特開 昭63−32196（ＪＰ，Ａ) 実開 昭62−45395（ＪＰ，Ｕ) ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Tomohisa Imai 1728 Omaeda, Hanazono-cho, Ozato-gun, Saitama 1 Mitsubishi Electric Home Equipment Co., Ltd. (56) Reference JP-A-63-32196 (JP, A) Sho 62-45395 (JP, U)
Claims (3)
脂の焼結成形法または発泡成形法で形成した、連通する
空孔をもつ多孔質の吸音層に、負圧面側を、この吸音層
の表面部を溶融して非通気性とした固溶層に一体に構成
された面状の２層部材で、回転する送風機の各羽根を構
成したことを特徴とする低騒音電動送風機。1. A pressure-absorbent surface against air during rotation is a porous sound-absorbing layer having communicating pores formed by a synthetic resin sintering molding method or a foam-molding method. A low-noise electric blower characterized in that each blade of a rotating blower is constituted by a planar two-layer member integrally formed with a solid solution layer in which a surface portion of the layer is melted to be air-impermeable.
たはセラミックスの粒体の焼結成形法で形成した、連通
する空孔をもつ多孔質の吸音層に、負圧面側を、この吸
音層の表面部を溶融して非通気性とした固溶層に一体に
構成された面状の２層部材で、回転する送風機の各羽根
を構成したことを特徴とする低騒音電動送風機。2. A pressure-absorbing surface side against air during rotation is formed on a porous sound-absorbing layer having communicating pores, which is formed by a sinter-molding method of metal or ceramic particles, and a suction-side surface is provided with this sound-absorbing surface. A low-noise electric blower characterized in that each blade of a rotating blower is constituted by a planar two-layer member integrally formed with a solid solution layer in which a surface portion of the layer is melted to be air-impermeable.
肉厚の制御で行うようにした特許請求の範囲第１項また
は第２項に記載の低騒音電動送風機。3. The low noise electric blower according to claim 1 or 2, wherein the blade strength is set by controlling the thickness of the solid solution layer to be generated.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63325273A JP2682545B2 (en) | 1988-12-23 | 1988-12-23 | Low noise electric blower |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63325273A JP2682545B2 (en) | 1988-12-23 | 1988-12-23 | Low noise electric blower |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02173398A JPH02173398A (en) | 1990-07-04 |
| JP2682545B2 true JP2682545B2 (en) | 1997-11-26 |
Family
ID=18174970
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63325273A Expired - Fee Related JP2682545B2 (en) | 1988-12-23 | 1988-12-23 | Low noise electric blower |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2682545B2 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2679428B2 (en) * | 1991-03-18 | 1997-11-19 | 三菱電機株式会社 | Silencer ventilation |
| JPH0979199A (en) * | 1995-09-13 | 1997-03-25 | Hitachi Ltd | Motor-driven air blower |
| CN101213373B (en) | 2005-07-04 | 2012-05-09 | 贝洱两合公司 | Impeller |
| JP2010053414A (en) * | 2008-08-29 | 2010-03-11 | Mitsubishi Electric Corp | Porous material, sound absorbing and insulating structure, electric equipment, vacuum cleaner and method for producing porous material |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS4938564U (en) * | 1972-07-05 | 1974-04-05 | ||
| JPS56146096A (en) * | 1980-04-15 | 1981-11-13 | Mitsubishi Electric Corp | Blower |
| JPS5945134A (en) * | 1982-09-09 | 1984-03-13 | Honda Motor Co Ltd | Manufacture of resin molding |
| JPS62237099A (en) * | 1986-04-08 | 1987-10-17 | Matsushita Electric Ind Co Ltd | Electric blower |
| JPS62248553A (en) * | 1986-04-19 | 1987-10-29 | Kubota Ltd | Production of two layer hollow cylindrical body |
| JPS6332196A (en) * | 1986-07-25 | 1988-02-10 | N D C Kk | Low noise fan |
-
1988
- 1988-12-23 JP JP63325273A patent/JP2682545B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH02173398A (en) | 1990-07-04 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |