JP2005291049A

JP2005291049A - Casing for centrifugal fan

Info

Publication number: JP2005291049A
Application number: JP2004105665A
Authority: JP
Inventors: Yoichi Nagata; 洋一永田
Original assignee: Japan Servo Corp
Current assignee: Nidec Advanced Motor Corp
Priority date: 2004-03-31
Filing date: 2004-03-31
Publication date: 2005-10-20

Abstract

<P>PROBLEM TO BE SOLVED: To improve performance of air capacity and static pressure by suppressing pressure reduction of discharge air at a discharge port in a casing of a centrifugal fan, particularly a casing constituted to have the short discharge port. <P>SOLUTION: The casing for the centrifugal fan is constituted such that a nose part tongue of the discharge port has a circular arc surface enlarged toward the end of the discharge port, preferably has a circular arc surface communicating with an enlarged angle within a range of 24-33° of an open angle of a line connecting the most downstream part of an inner peripheral circular arc surface of a ventilation flue to the discharge port side face of the nose part tongue to specify the nose side tongue shape of the discharge port located downstream of ventilation. The discharge port end part is thereby formed in circular arc shape enlarged toward the edge to improve the performance of both air capacity and static pressure. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

本発明は、風量・静圧両面での性能向上を実現するための、遠心ファンのケーシングに関する。 The present invention relates to a centrifugal fan casing for realizing performance improvement in both air volume and static pressure.

特開平０９−２２８９９７号公報JP 09-228997 A

上述周知先願も、遠心ファンの風速・風量両性能の改善策の一例で、該例だけでなく、改善効果を実現するためには種々の構成が提案されており、夫々相応の効果を実現している。 The above-mentioned known prior application is also an example of a measure for improving both the wind speed and air volume performance of a centrifugal fan. Not only this example but also various configurations have been proposed to realize the improvement effect, and corresponding effects are realized. doing.

しかし、上述の如き従来の構成は、いずれも何らかの部材付加を伴うもので、構造上の複雑化を余儀なくされることから、コストの面でのデメリットを抱えているのが実態であった。 However, all of the conventional configurations as described above involve some kind of member addition, and the structure is inevitably complicated, so that there is a demerit in terms of cost.

本発明に成る遠心ファンのケーシングは、吐出口のノーズ部舌が、吐出口端に向かって拡大する円弧状面を有し、好ましくは、 The casing of the centrifugal fan according to the present invention has an arcuate surface in which the nose portion tongue of the discharge port expands toward the discharge port end,

前記通風路内周円弧面の最下流部位とノーズ部舌の吐出口側面とを結ぶ線の開き角が２４°から３３°の範囲で、該拡大角に連通する円弧状面を備えるように形成されている。 An opening angle of a line connecting the most downstream portion of the inner circular arc surface of the ventilation path and the discharge port side surface of the nose tongue is formed in a range of 24 ° to 33 ° so as to have an arc-shaped surface communicating with the enlarged angle. Has been.

本発明に成る遠心ファンのケーシングは、吐出口における吐出空気の圧力減殺の抑制による風量・静圧双方の性能向上を実現している。 The casing of the centrifugal fan according to the present invention realizes improvement in both air volume and static pressure by suppressing the pressure loss of the discharge air at the discharge port.

以下図面によって本発明の実施例を説明する。 Embodiments of the present invention will be described below with reference to the drawings.

図１は本発明のノーズ部舌の形状を説明する断面略図で、ノーズ部舌が、先頭端から吐出口端縁に向かって拡大する円弧状を有していることを示している。 FIG. 1 is a schematic cross-sectional view illustrating the shape of the nose tongue of the present invention, and shows that the nose tongue has an arc shape that expands from the leading end toward the discharge port edge.

周知の通り、遠心ファンの最大静圧は、羽根車の中心からの舌部の位置で決まり、最大風量は、吐出口の面積で決まるので、舌部の位置を静圧の高い位置にしたままで吐出口の面積を大きくするため、拡大する円弧状面を形成している。 As is well known, the maximum static pressure of the centrifugal fan is determined by the position of the tongue from the center of the impeller, and the maximum airflow is determined by the area of the discharge port, so the position of the tongue is kept at a high static pressure position. In order to increase the area of the discharge port, an expanding arcuate surface is formed.

上述ノーズ部舌の拡大は、通風路外周側のケーシング内面に対する、通風路内周円弧面の最下流部位とノーズ部舌の吐出口側面とを結ぶ線の開き角が２４°から３３°の範囲で、該拡大角に連通する円弧状面を形成すると効果的であることが確認されている。 The expansion of the nose portion tongue is such that the opening angle of the line connecting the most downstream portion of the inner circular arc surface of the ventilation passage and the discharge port side surface of the nose portion tongue with respect to the casing inner surface on the outer circumferential side of the ventilation passage is in the range of 24 ° to 33 ° Thus, it has been confirmed that it is effective to form an arcuate surface communicating with the enlarged angle.

また、従来技術でも吐出口を拡大する手段は採用されている。図２では、通風路外周側のケーシング内面に対する、通風路内周円弧面の最下流部位とノーズ部舌の吐出口側面とを結ぶ線の開き角：θが、一定の角度で拡大しているもので、図４に実用領域での２７°と３３°の例を、従来技術イと同ロとして示す通り、汎用構造である図３の例に対し静圧アップを実現しているが、本願発明に成る円弧状拡大面を有する構成は更なる風量特性の改善を実現している。 In the prior art, means for enlarging the discharge port is also employed. In FIG. 2, the opening angle θ of the line connecting the most downstream portion of the inner circular arc surface of the ventilation passage and the discharge port side surface of the tongue of the nose portion with respect to the inner surface of the casing on the outer circumferential side of the ventilation passage is enlarged at a constant angle. However, as shown in FIG. 4 in which the 27 ° and 33 ° examples in the practical area are the same as the prior art A, the static pressure is increased compared to the example of FIG. The configuration having the arc-shaped enlarged surface according to the invention realizes further improvement of the air flow characteristic.

本発明に成る遠心ファンのケーシングは、吐出口における吐出空気の圧力減殺での風量・静圧双方の性能改善を両立させることを目的に、広く利用できる。 The casing of the centrifugal fan according to the present invention can be widely used for the purpose of achieving both improvement in performance of both air volume and static pressure by reducing the pressure of discharged air at the discharge port.

本発明に成る例を説明する為の正面透視略図である。1 is a schematic front perspective view for explaining an example according to the present invention. 従来技術での改良された例を説明する為の正面透視略図である。1 is a schematic front perspective view for explaining an improved example in the prior art. 従来技術で周知の例を説明する為の正面透視略図である。It is a front perspective schematic diagram for demonstrating an example known by a prior art. 発明技術と周知従来技術での例による性能を対比する性能比較図である。FIG. 6 is a performance comparison diagram comparing the performance of the inventive technique and the known prior art example.

Explanation of symbols

１ケーシング
１−１吸込口
１−２吐出口
１−３ノーズ部舌
１−３１舌の拡大円弧状面
１−３２舌の拡大平面
１−３３舌の並行面
２多翼羽根車
２−１多翼羽根車の外周面（通風路内周円弧面）
θ 通風路外周側のケーシング内面に対する、通風路内周円弧面の最下流部位とノーズ部舌の吐出口側面とを結ぶ線の開き角
Ｒ舌の拡大円弧状面の円弧径 DESCRIPTION OF SYMBOLS 1 Casing 1-1 Suction port 1-2 Discharge port 1-3 Nose part tongue 1-31 Expanded arc-shaped surface of tongue 1-32 Expanded plane of tongue 1-33 Parallel surface of tongue 2 Multi-blade impeller 2-1 Many Outer peripheral surface of impeller (circumferential inner circular arc surface)
θ The opening angle of the line connecting the most downstream portion of the inner circular arc surface of the ventilation passage and the discharge port side surface of the nose tongue with respect to the inner surface of the casing on the outer circumferential side of the ventilation passage R The arc diameter of the enlarged circular arc surface of the tongue

Claims

The size of the ventilation path formed by the inner peripheral surface of the casing and the outer peripheral edge of the impeller gradually increases from the upstream side to the downstream side, and is smaller on the nose side of the most downstream discharge port. A centrifugal fan casing in communication with a gap portion, wherein the nose portion tongue of the discharge port has an arcuate surface expanding toward the discharge port end.

An opening angle of a line connecting the most downstream portion of the inner circular arc surface of the ventilation path and the discharge port side surface of the nose tongue is provided with an arc-shaped surface communicating in a range of 24 ° to 33 °. Item 5. A centrifugal fan casing according to Item 1.