JPH09287594A - Fan blade formed into point symmetrical blade profile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To rotate normally and reversely by the same blade profile by point- symmetrically positioning the coordinates of the belly side and the back side of a fan blade against the center of gravity of the blade. SOLUTION: This blade profile of a fan blade 1 is formed so that the coordinates of the belly side 1a and the back side 1b of the blade are positioned point-symmetrically against the center of gravity 2 of the blade and a little narrow part is formed in the vicinity of the center of gravity 2, or it is formed into a point symmetrical shape of hardly changing the blade thickness. By making the coordinates of the belly side of the back side of the fan blade into a point symmetric shape positioning them point-symmetrically against the center of gravity of the blade, the flowing-in condition of air current against the blade becomes equal at normal rotation and at reverse rotation, and hence the same wind quantity and thrust can be provided at normal rotation and at reverse rotation. In addition, the cascade of blades can be made into one line, hence the cost can be reduced and noise can be reduced because the factor disturbing flow on the lower stream of moving blades is reduced.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【発明の属する技術分野】本発明はトンネル換気用ファ
ンのような正転時と逆転時に同等の風量と推力を必要と
するファンに適用される点対称翼型から成るファン翼に
関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fan blade of a point-symmetrical blade type, which is applied to a fan such as a tunnel ventilation fan which requires an equal amount of air and thrust at the time of forward rotation and reverse rotation.

【０００２】[0002]

【従来の技術】従来の正転、逆転で同等の風量と推力を
必要とするファンは図５に示すように翼の腹側と背側の
座標が、翼の重心に対し線対称の翼型１２から成り、こ
れを図６に示すように正転用と逆転用に２列使い、互い
に反対方向を向けて、それぞれ図７に示すようにケーシ
ング３にストラット４を介して取り付けられるモータ５
の前後のボス６、６に取付けられ、この２つのボス６、
６は同じ方向に回転し、一方向に気流を発生する。2. Description of the Related Art A conventional fan that requires the same air volume and thrust in forward and reverse rotation has a blade shape in which the ventral and dorsal coordinates of the blade are line-symmetric with respect to the center of gravity of the blade, as shown in FIG. The motor 5 is composed of 12 motors, which are used in two rows for forward rotation and reverse rotation as shown in FIG. 6, and are oriented in mutually opposite directions, and are respectively attached to the casing 3 through the struts 4 as shown in FIG.
Attached to the front and rear bosses 6, 6, these two bosses 6,
6 rotates in the same direction and generates an air flow in one direction.

【０００３】[0003]

【発明が解決しようとする課題】しかし図７に示すよう
にモータの前後のボスに正転、逆転両用の翼型を２列に
渉って設けるものでは正転時には、２列目の逆転用翼列
が若干の風量、推力を発揮するものの、流れに対し適正
に配置されていないため翼列下流の流れを乱し、騒音が
大きくなる。また翼列が２列があることは１列に比べて
コストが大きくなる等の問題点を有している。However, as shown in FIG. 7, in the case where the bosses for the forward and backward rotation of the motor are provided in two rows for both normal rotation and reverse rotation, in the case of forward rotation, the reverse rotation for the second row is performed. Although the blade row exerts a small amount of airflow and thrust, it is disturbed in the flow downstream of the blade row because it is not properly arranged with respect to the flow, and noise increases. Further, the fact that there are two rows of blades has a problem that the cost becomes higher than that of one row.

【０００４】本発明はかかる問題点に対処するため開発
されたものであって正転と逆転とを同じ翼型で可能とす
ることを目的とする。The present invention was developed to address such a problem, and an object of the present invention is to enable normal rotation and reverse rotation with the same airfoil shape.

【０００５】[0005]

【課題を解決するための手段】上記の目的を達成するた
めの本発明の構成は翼の腹側と背側の座標が、翼の重心
に対し点対称な位置にあることを特徴とする。The structure of the present invention for achieving the above object is characterized in that the coordinates of the ventral side and the dorsal side of the blade are at positions symmetrical with respect to the center of gravity of the blade.

【０００６】[0006]

【発明の実施の形態】図１は本発明のファン翼の一実施
例を示す断面図で、該ファン翼１はその翼型を翼の腹側
１ａと背側１ｂの座標が、翼の重心２に対し点対称な位
置にある点対称翼型とし、図１（ａ）では重心２付近で
少しくびれをもつ点対称翼型を示し、図１（ｂ）では翼
厚がほとんど変化しない点対称翼型を示す。1 is a cross-sectional view showing an embodiment of a fan blade of the present invention. The fan blade 1 has a blade shape whose coordinates on the ventral side 1a and the back side 1b of the blade are the center of gravity of the blade. 2 is a point-symmetric airfoil in a point-symmetrical position with respect to 2, and FIG. 1 (a) shows a point-symmetric airfoil with a slight constriction near the center of gravity 2. In FIG. 1 (b), the blade thickness is almost unchanged. The wing shape is shown.

【０００７】図２は前記ファン翼１の取付状態を示す概
略図で、ファン翼１はケーシング３にストラット４を介
して取付けられるモータ５びボス６に取付けられ、その
取付けは図３に示すようにボス６に適宜の間隔を設けて
一列に取付けられており、モータ５の回転方向に従って
正逆回転する。そして正転時の気流方向は図４（ａ）に
示すようにモータ５の正転回転方向７に対し直交する正
転気流８と、図４（ｂ）に示すようにモータ５の逆転回
転方向９に対し直交する逆転気流１０となり、その翼型
に対する速度三角形は図４に示すように正転時と逆転時
において翼の取付角θは変化せず、回転数も同じである
ため気流の翼に対する角度β₁ は変化しない。このため
風量、推力は正転時と逆転時で同等となる。図中１１は
モータ下流の流れを整流するテールコーンを示す。FIG. 2 is a schematic view showing a mounting state of the fan blade 1. The fan blade 1 is mounted on a motor 5 and a boss 6 which are mounted on a casing 3 through struts 4, and the mounting is as shown in FIG. The bosses 6 are attached to the bosses 6 in a line at appropriate intervals and rotate in the forward and reverse directions according to the rotation direction of the motor 5. As shown in FIG. 4 (a), the air flow direction during normal rotation is a normal rotation air flow 8 orthogonal to the normal rotation direction 7 of the motor 5 and the reverse rotation direction of the motor 5 as shown in FIG. 4 (b). As shown in FIG. 4, the airflow blade 10 has a reverse airflow 10 that is orthogonal to 9 and its velocity triangle does not change during normal rotation and reverse rotation, and the rotation speed is the same. The angle β ₁ with respect to does not change. Therefore, the air volume and thrust are the same in forward rotation and reverse rotation. Reference numeral 11 in the figure denotes a tail cone that rectifies the flow downstream of the motor.

【０００８】[0008]

【発明の効果】このように本発明によるときはファン翼
を、翼の腹側と背側の座標が、翼の重心に対し、点対称
な位置にある点対称翼型としたものであるから正転時と
逆転時で翼に対する気流の流入条件が同じであるため、
正転逆転時で同等の風量と推力を得ることができ、又翼
列を１列とすることが可能となるためコストの低減にな
ると共に動翼下流で流れを乱すものが少なくなるため低
騒音となる等の効果を有する。As described above, according to the present invention, the fan blade is a point-symmetrical blade type in which the ventral and dorsal coordinates of the blade are point-symmetrical with respect to the center of gravity of the blade. Since the airflow inflow condition to the blade is the same during forward rotation and reverse rotation,
It is possible to obtain the same air volume and thrust at the time of normal rotation and reverse rotation, and it is possible to reduce the cost because the blade row can be one row, and the noise that disturbs the flow is reduced downstream of the blade. And so on.

【図面の簡単な説明】[Brief description of drawings]

【図１】本発明の翼型の一実施例を示す断面図である。FIG. 1 is a cross-sectional view showing an embodiment of an airfoil of the present invention.

【図２】本発明の翼型の取付け状況を示す概略図であ
る。FIG. 2 is a schematic view showing a mounting state of the airfoil of the present invention.

【図３】図２の翼列の斜視図である。3 is a perspective view of the blade row of FIG. 2. FIG.

【図４】翼型に対する正転、逆転時の速度三角形図であ
る。FIG. 4 is a velocity triangle diagram for forward and reverse rotations with respect to an airfoil.

【図５】従来の翼型を示す断面図である。FIG. 5 is a cross-sectional view showing a conventional airfoil.

【図６】従来の翼型の翼列図である。FIG. 6 is a blade array diagram of a conventional airfoil.

【図７】従来の翼型の取付け状況を示す概略図である。FIG. 7 is a schematic view showing a mounting state of a conventional airfoil.

【符号の説明】[Explanation of symbols]

１ ファン翼 １ａ 腹側 １ｂ 背側 ２ 重心 1 fan blade 1a ventral side 1b dorsal side 2 center of gravity

Claims (1)

【特許請求の範囲】[Claims] 【請求項１】 翼の腹側と背側の座標が、翼の重心に対
し点対称な位置にあることを特徴とする点対称翼型から
成るファン翼。1. A fan blade having a point-symmetrical blade shape, wherein the ventral and dorsal coordinates of the blade are located symmetrically with respect to the center of gravity of the blade.