JP3690075B2

JP3690075B2 - Bidirectional axial blower

Info

Publication number: JP3690075B2
Application number: JP19139097A
Authority: JP
Inventors: 道弘西; 直史塚本
Original assignee: Fuji Electric Systems Co Ltd
Current assignee: Fuji Electric Co Ltd
Priority date: 1997-07-16
Filing date: 1997-07-16
Publication date: 2005-08-31
Anticipated expiration: 2017-07-16
Also published as: JPH1137093A

Description

【０００１】
【発明の属する技術分野】
この発明は、自動車道路用トンネル内の換気用として使用するジエットファンを対象とした双方向型軸流送風機に関する。
【０００２】
【従来の技術】
頭記したトンネル用のジェットファンは、トンネル内を通り抜ける自然風の風向きに合わせて送風方向を正，逆に反転して運転するものであり、その具体的な構成として、翼形の動翼からなる正転用羽根車とその駆動モータ，および翼形の動翼からなる逆転用羽根車とその駆動モータを同軸上に並べて筒状ケーシング内に収設し、前記駆動モータの一方を選択的に運転し、他方を運転停止して送風方向を正，逆に切り換えるようにした双方向型軸流送風機として、特開平４−１７５５００号公報に示されるものが既に提案されている。
【０００３】
図２は前記提案を基にした双方向型軸流送風機の従来構造図である。図において、１はトンネル内の天井側に据付けけた前後端面開放形の筒状ケーシング、２は翼形の動翼２ａからなる正転用羽根車、３はその駆動モータ、４は翼形の動翼４ａからなる逆転用羽根車、５はその駆動モータ、６は駆動モータ３，５をケーシング１内に固定する支柱を兼ねた円柱状，もしくは送風方向に平行な平板状ないし偏平状のステーベーン、７は正転用羽根車２，および逆転用羽根車４の吸込側（上流）に配したコーン状のハブである。
【０００４】
ここで、駆動モータ３，５は背中合わせに並べてケーシング１の中央部に配置し、各駆動モータ３，５に連結した羽根車２，４は駆動モータ３，５を挟んでその外側（軸方向）に配置した配列になる。
かかる構成で、図の左側から右側に向けて送風する（送風方向Ａ）場合には、駆動モータ３を運転して正転用羽根車２を矢印ａ方向に回転駆動し、他方の駆動モータ５を非拘束のまま運転を停止する。また、送風方向を切換えて右側から左側に送風する（送風方向Ｂ）場合には、前記とは逆に駆動モータ５を運転して逆転用羽根車４を矢印ｂ方向に回転駆動し、他方の駆動モータ３は非拘束のまま運転を停止している。
【０００５】
【発明が解決しようとする課題】
ところで、前記した従来の構成では送風効率，騒音などの面で次のような問題点がある。すなわち、
(1) 駆動モータ３，５のいずれかを運転して羽根車２，または４を駆動すると、その動翼の回転により羽根車から下流側へ向けて旋回しながら吐き出す送風気流は軸流方向に並ぶ駆動モータ３，および５の各ステーベーン７と衝突を繰り返しながら下流側に向けて送風される。この場合にステーベーン７は送風方向の正，逆切換えに対応させるように、前記のように円柱状，もしくは送風方向と平行な平板で構成さている。このために、羽根車２，４の動翼２ａ，４ａから吐き出される旋回気流と送風経路に沿って直列に並ぶステーベーン７との衝突の繰り返しで発生する風損が大きくなって送風効率が低下する。
【０００６】
(2) 駆動モータ３，５のいずれか一方を運転して送風している状態で、他方の停止側の駆動モータ，およびその羽根車を非拘束状態のままにしているので、下流側に並ぶ停止中の羽根車が駆動側羽根車の吐出し風力を受けて回転することになる。しかして、停止側の駆動モータ，羽根車が駆動側羽根車の風力で回転すると、その回転に伴い軸受の摩擦損、および送風気流による動翼表面での剥離損失が生じ、駆動側羽根車の送風力の一部が前記の損失分に費やされるため送風機としての効率が低下する。
【０００７】
(3) 正転用，逆転用の羽根車２，４は駆動モータ３，５を中央に挟んでケーシング１の開口端に近く位置しているために、羽根車２，４の回転によりケーシング１の開口端を通じて周囲に伝播する動翼風切り音による騒音が大となる。
この発明は上記の点に鑑みなされたものであり、その目的は前記問題点を解決し、風損，騒音レベルを低減して送風効率の向上，低騒音化が図れるように改良した双方向型軸流送風機を提供することにある。
【０００８】
【課題を解決するための手段】
上記目的を達成するために、この発明によれば、翼形の動翼からなる正転用羽根車とその駆動モータ，および翼形の動翼からなる逆転用羽根車とその駆動モータを同軸上に並べて筒状ケーシング内に収設し、前記駆動モータの一方を選択的に運転し、他方を運転停止して送風方向を正，逆に切り換えるようにした双方向型軸流送風機において、
(1) 正転用羽根車と逆転用羽根車とを向かい合わせに並べてケーシング内の中央に配置し、各羽根車の駆動モータをその両側に配置する（請求項１）。
【０００９】
(2) 送風方向に対して運転停止の羽根車が上流側，運転中の羽根車が下流側に位置するように正転用，逆転用羽根車を配置する（請求項２）。
(3) 正転用，逆転用羽根車の駆動モータのうち、一方の駆動モータを運転して送風を行っている際に、停止側の駆動モータ，およびその羽根車を回転しないように拘束する（請求項３）。
【００１０】
上記の構成によれば、駆動側の羽根車から下流側に向けて吐き出す旋回気流は、駆動側羽根車の駆動モータのステーベーンと衝突するだけで、上流側に位置する停止側駆動モータのステーベーンと衝突することがなく、したがってステーベーンとの衝突により生じる風損が従来構成と較べて半減し、これにより送風機の効率が向上する。
【００１１】
また、正転用，逆転用の羽根車を向かい合わせてケーシングの中央部に配置したことにより、羽根車とケーシングの開口端との間の距離が遠く離れるので、その分だけ羽根車から発生してケーシングの開口端から周囲に伝播する騒音が低下する。
さらに、駆動側羽根車の上流側に位置する停止側の羽根車が送風気流を受けて回らないように拘束することで、この停止側の羽根車の翼形動翼が駆動側の羽根車に対する風向ガイドベーンとして有効に働き、ケーシング内に吸い込んだ直進気流を駆動側羽根車の動翼の迎え角に沿って流れるような旋回流に変える。これにより駆動側羽根車の動翼に生じる剥離損失が低減して送風効率が向上する。
【００１２】
【発明の実施の形態】
以下、この発明の実施の形態を図１の実施例に基づいて説明する。なお、実施例の図中で図２に対応する同一部材には同じ符号が付してある。
図１の実施例では、ケーシング１の内部に組み込んだ正転用羽根車２と逆転用羽根車４を向かい合わせに並べてケーシング内の中央に配置し、各羽根車の駆動モータ３，５が羽根車２，４を挟んでその両側に配置されている。ここで、羽根車２，４は、矢印Ａ，Ｂで示す正，逆の送風方向に対して、停止側の羽根車が上流，駆動側の羽根車が下流側となるようにに正転用，逆転用羽根車２，４の各動翼の向きを定めて配列する。また、駆動モータ３，５には電源側にインバータ８を接続し、その出力周波数を変えて駆動側羽根車の回転速度制御，並びに停止中の羽根車が送風気流を受けて回らないように拘束制御（出力周波数が０）するようにしている。
【００１３】
かかる構成で、矢印Ａ方向に送風する場合には、駆動モータ３を運転して正転用羽根車２を駆動し、停止側の駆動モータ５はインバータ８の制御で羽根車４が回らないように拘束しておく。これにより、ケーシング１の開口面１ａ（左側）より流入してケーシング内を直進する吸込空気流は停止側羽根車４の動翼４ａを通過する過程でその翼面に沿って右回転の旋回流となり、その下流側に並ぶ正転用羽根車２に流入する。つまり、停止側の羽根車４の動翼４ａが駆動側の羽根車２に対する風向ガイドベーンとして働き、ここを通過する吸込み気流に駆動側羽根車２の動翼２ａの迎え角に適合した流入角を与える。そして正転用羽根車２から吐出した気流はケーシング１内を旋回しながら駆動モータ３のステーベーン６を通過し、ケーシング１の開口端１ａより下流側に放出する。
【００１４】
一方、送風機の送風方向を矢印Ｂ方向に切換えて運転する場合には、前記とは逆に駆動モータ５を運転して逆転用羽根車４を駆動し、駆動モータ３をインバータ制御により拘束して正転用羽根車２が送風流で回らないようにする。この場合でも、前記と同様に停止中の正転用羽根車２の動翼２ａが駆動側の逆転用羽根車４に対する風向ガイドベーンとして機能することになる。
【００１５】
なお、停止側の羽根車を拘束する手段としては、駆動モータ３，５に機械的なブレーキを付設することもできる。
また、上記の構成によれば、図示のように羽根車２，４がケーシング１の開口端１ａ，１ｂから遠く離れた中央部に配置されていので、羽根車２，４の回転に伴って発生する騒音（動翼の風切り音）はケーシングの内部で多少減衰し、ケーシング１の開口端より周囲に伝播する騒音レベルが図２に示した従来構成と較べて低下する。
【００１６】
さらに、送風方向Ａ，Ｂに対して停止中の羽根車は駆動側の羽根車の上流側に位置しているので、駆動側羽根車から吐出した旋回気流が停止側羽根車の駆動モータを支えているステーベーンと衝突することがなく、これにより図２の従来構成と較べて風損が半減する。
【００１７】
【発明の効果】
以上述べたように、この発明の構成によれば、従来構成の送風機と較べて、風損，騒音レベルを低減し、低騒音で送風効率の高い双方向型軸流送風機を提供することができる。
【図面の簡単な説明】
【図１】この発明の実施例による双方向型軸流送風機の構成図
【図２】従来における双方向型軸流送風機の構成図
【符号の説明】
１ケーシング
２正転用羽根車
２ａ動翼
３正転用羽根車の駆動モータ
４逆転用羽根車
４ａ動翼
５逆転用羽根車の駆動モータ
６ステーベーン[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a bidirectional axial fan for a jet fan used for ventilation in a tunnel for an automobile road.
[0002]
[Prior art]
The tunnel jet fan mentioned above is operated by reversing the air flow direction forward and backward in accordance with the direction of the natural wind passing through the tunnel. The forward impeller and its drive motor, and the reverse impeller consisting of an airfoil blade and its drive motor are coaxially arranged in a cylindrical casing, and one of the drive motors is selectively operated However, as a bidirectional axial flow blower in which the other is stopped and the air blowing direction is switched between forward and reverse, the one disclosed in JP-A-4-175500 has already been proposed.
[0003]
FIG. 2 is a conventional structural view of a bidirectional axial flow fan based on the above proposal. In the figure, 1 is a cylindrical casing with an open front and rear end face installed on the ceiling side in a tunnel, 2 is a forward impeller comprising an airfoil blade 2a, 3 is its drive motor, and 4 is an airfoil blade. 4a, a reverse impeller 5a, 5 a drive motor, 6 a cylindrical shape that also serves as a support for fixing the drive motors 3 and 5 in the casing 1, or a flat or flat stay vane parallel to the blowing direction, 7 Is a cone-shaped hub arranged on the suction side (upstream) of the forward impeller 2 and the reverse impeller 4.
[0004]
Here, the drive motors 3 and 5 are arranged back to back in the center of the casing 1, and the impellers 2 and 4 connected to the drive motors 3 and 5 are outside (axial direction) across the drive motors 3 and 5. It becomes an array arranged in.
In such a configuration, when the air is blown from the left side to the right side in the figure (air blowing direction A), the drive motor 3 is operated to rotate the forward rotation impeller 2 in the direction of arrow a, and the other drive motor 5 is driven. Stop operation without being restrained. Further, when the air blowing direction is switched and the air is blown from the right side to the left side (air blowing direction B), the driving motor 5 is operated in reverse to the above to rotate the impeller 4 for reverse rotation in the direction of the arrow b, and the other The drive motor 3 has stopped operating without being restrained.
[0005]
[Problems to be solved by the invention]
By the way, the above-described conventional configuration has the following problems in terms of blowing efficiency and noise. That is,
(1) When either one of the drive motors 3 and 5 is operated to drive the impeller 2 or 4, the blast airflow discharged while turning toward the downstream side from the impeller is rotated in the axial direction by the rotation of the moving blade. The air is blown toward the downstream side while repeatedly colliding with the respective stay vanes 7 of the drive motors 3 and 5 arranged side by side. In this case, the stay vane 7 is formed in a columnar shape or a flat plate parallel to the air blowing direction as described above so as to correspond to forward / reverse switching of the air blowing direction. For this reason, the windage loss generated by repeated collision between the swirling airflow discharged from the rotor blades 2a and 4a of the impellers 2 and 4 and the stay vanes 7 arranged in series along the airflow path is increased, and the airflow efficiency is lowered. .
[0006]
(2) Since one of the drive motors 3 and 5 is operating and blowing air, the other stop side drive motor and its impeller are left in an unconstrained state, so they are arranged downstream. The impeller being stopped rotates by receiving the discharge wind force of the driving side impeller. Thus, when the drive motor and impeller on the stop side are rotated by the wind power of the drive impeller, the friction loss of the bearing and the separation loss on the moving blade surface due to the air flow occur with the rotation. Since a part of the blowing power is consumed for the loss, the efficiency as a blower is lowered.
[0007]
(3) Since the impellers 2 and 4 for normal rotation and reverse rotation are located close to the opening end of the casing 1 with the drive motors 3 and 5 in the center, the rotation of the impellers 2 and 4 causes the casing 1 Noise due to wind noise from the blade propagating to the surroundings through the open end becomes large.
The present invention has been made in view of the above points, and an object of the present invention is to solve the above problems and improve the bidirectional type so as to reduce windage loss and noise level to improve blowing efficiency and reduce noise. The object is to provide an axial blower.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, a forward rotation impeller composed of an airfoil-shaped moving blade and its drive motor, and a reverse rotation impeller composed of an airfoil-shaped moving blade and its drive motor are coaxially arranged. In a bidirectional axial flow fan that is arranged side by side in a cylindrical casing, selectively operates one of the drive motors, stops the other operation, and switches the blowing direction to normal or reverse,
(1) A forward impeller and a reverse impeller are arranged face to face in the center of the casing, and drive motors for the respective impellers are disposed on both sides thereof.
[0009]
(2) The forward and reverse impellers are arranged so that the impeller that is not operating is located upstream and the impeller that is operating is located downstream relative to the blowing direction.
(3) When driving one of the forward and reverse impeller drive motors to blow air, the stop drive motor and the impeller are restrained from rotating ( Claim 3).
[0010]
According to the above configuration, the swirling airflow discharged from the drive-side impeller toward the downstream side only collides with the stay vane of the drive motor of the drive-side impeller, and the stay vane of the stop-side drive motor positioned on the upstream side. There is no collision, and therefore the windage loss caused by the collision with the stay vanes is halved compared to the conventional configuration, thereby improving the efficiency of the blower.
[0011]
In addition, since the impeller for normal rotation and reverse rotation are arranged facing each other in the center part of the casing, the distance between the impeller and the open end of the casing is far away, so that the impeller is generated by that much. Noise transmitted from the open end of the casing to the surroundings is reduced.
Further, by restraining the stop-side impeller located upstream of the drive-side impeller from receiving air flow and turning it, the airfoil blades of the stop-side impeller against the drive-side impeller It works effectively as a wind guide vane, and changes the straight air flow sucked into the casing into a swirl flow that flows along the angle of attack of the moving blade of the driving impeller. Thereby, the peeling loss which arises in the moving blade of a drive side impeller reduces, and ventilation efficiency improves.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described based on the embodiment of FIG. In the drawings of the embodiments, the same members corresponding to those in FIG.
1, the forward impeller 2 and the reverse impeller 4 incorporated in the casing 1 are arranged face to face in the center of the casing, and the drive motors 3 and 5 of each impeller are impellers. 2 and 4 are arranged on both sides thereof. Here, the impellers 2 and 4 are for forward rotation so that the impeller on the stop side is upstream and the impeller on the drive side is downstream with respect to the forward and reverse air blowing directions indicated by arrows A and B. The moving blades of the reverse rotation impellers 2 and 4 are arranged with their directions determined. In addition, an inverter 8 is connected to the drive motors 3 and 5 on the power source side, and the output frequency is changed to control the rotational speed of the drive-side impeller, and the stopped impeller is restrained from receiving airflow and turning. Control (output frequency is 0) is made.
[0013]
With this configuration, when the air is blown in the direction of arrow A, the drive motor 3 is operated to drive the forward rotation impeller 2, and the stop-side drive motor 5 is controlled by the inverter 8 so that the impeller 4 does not rotate. Be restrained. As a result, the suction air flow that flows in from the opening surface 1a (left side) of the casing 1 and travels straight in the casing passes through the rotor blade 4a of the stop-side impeller 4 and rotates rightward along the blade surface. And flows into the forward rotation impeller 2 arranged on the downstream side thereof. That is, the moving blade 4a of the impeller 4 on the stop side acts as a wind direction guide vane for the impeller 2 on the driving side, and the inflow angle adapted to the angle of attack of the moving blade 2a of the driving impeller 2 on the suction airflow passing therethrough give. The airflow discharged from the forward rotation impeller 2 passes through the stay vanes 6 of the drive motor 3 while turning in the casing 1 and is discharged downstream from the opening end 1 a of the casing 1.
[0014]
On the other hand, when the fan is operated by switching the blowing direction to the arrow B direction, the drive motor 5 is driven to drive the reverse rotation impeller 4 in the opposite manner, and the drive motor 3 is restrained by inverter control. The forward impeller 2 is prevented from rotating by the air flow. Even in this case, the moving blade 2a of the forward rotating impeller 2 that is stopped functions as a wind direction guide vane for the reverse rotating impeller 4 on the driving side as described above.
[0015]
As a means for restraining the impeller on the stop side, a mechanical brake can be attached to the drive motors 3 and 5.
Moreover, according to said structure, since the impellers 2 and 4 are arrange | positioned in the center part far from the opening ends 1a and 1b of the casing 1 as shown in figure, it generate | occur | produces with rotation of the impellers 2 and 4 The noise (winding noise of the moving blades) is somewhat attenuated inside the casing, and the noise level propagating from the opening end of the casing 1 to the surroundings is lower than the conventional configuration shown in FIG.
[0016]
Further, since the impeller that is stopped with respect to the air blowing directions A and B is located upstream of the drive-side impeller, the swirling airflow discharged from the drive-side impeller supports the drive motor of the stop-side impeller. The windage does not collide with the stay vanes, and the windage loss is halved compared to the conventional configuration of FIG.
[0017]
【The invention's effect】
As described above, according to the configuration of the present invention, it is possible to provide a bidirectional axial flow fan that reduces windage loss and noise level, has low noise, and has high blowing efficiency, as compared to a blower having a conventional structure. .
[Brief description of the drawings]
FIG. 1 is a block diagram of a bidirectional axial fan according to an embodiment of the present invention. FIG. 2 is a block diagram of a conventional bidirectional axial fan.
DESCRIPTION OF SYMBOLS 1 Casing 2 Forward rotation impeller 2a Rotor blade 3 Forward rotation impeller drive motor 4 Reverse rotation impeller 4a Rotor blade 5 Reverse rotation impeller drive motor 6 Stay vane

Claims

An impeller for forward rotation composed of an airfoil-shaped moving blade and its drive motor, and an impeller for reverse rotation composed of an airfoil-shaped moving blade and its drive motor are coaxially arranged in a cylindrical casing having both ends opened, and the drive In a bidirectional axial fan that selectively operates one of the motors and stops the other to switch the direction of air flow to normal or reverse, and makes the air flow forward and reverse. A bidirectional axial blower characterized in that the impellers are arranged side by side in the center and the drive motors of each impeller are arranged on both sides thereof.

2. A bidirectional axial blower according to claim 1, wherein the forward and reverse rotations are performed so that the impellers for which operation is stopped are arranged upstream and the impellers being operated are arranged on the downstream side in each of the forward and reverse air blowing directions. A bidirectional axial blower characterized in that an impeller is arranged.

The bidirectional axial blower according to claim 2, wherein one of the drive motors for the forward rotation and the reverse rotation impeller is operated to blow air, and the stop side drive motor, and A bidirectional axial blower characterized in that the impeller is restrained from rotating so as to blow air.