JP3938252B2 - Multi-blade blower - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a multiblade fan used in a ventilation fan. The height of the front auxiliary tongue between the front panel and the impeller, the height of the main tongue of the impeller, and the height of the back auxiliary tongue between the back panel and the impeller are all from the center line of the impeller. Of height.
[0002]
[Prior art]
Conventional multiblade fans generally have the configuration shown in FIGS. 8 and 9.
[0003]
The configuration will be described below with reference to the drawings.
As shown in the figure, the multiblade blower main body 101 includes a scroll casing 102 having a spiral ventilation path 102A sandwiched between a front panel 102B provided with a suction port 105 having a bell mouth shape 113 and a back panel 102C having no suction port. In this configuration, an impeller 104 composed of a plurality of blades 104A locked to the end of the shaft 103A of the electric motor 103, a suction port 105, and a discharge port 106 are provided.
[0004]
In the above configuration, the impeller 104 rotates by rotating the rotating shaft of the electric motor 103, the air 107 is sucked from the suction port 105, flows into the scroll casing 102, and is pressurized by the rotation of the impeller 104, and the discharge port 106 is discharged.
[0005]
In this multiblade blower, the peripheral speed distribution on the side plate 109 side and main plate 110 side of the impeller 104 on the outer periphery 108 of the impeller 104 is not uniform, and when the blower static pressure increases, the side plate 109 side of the impeller 104 around the tongue 111. In addition, a back flow 112 was generated in the gap between the main plate 110 side and the back panel 102C, and a large back flow 112 in the vicinity of the tongue 111 was generated.
[0006]
[Problems to be solved by the invention]
In such a conventional multiblade fan, there is a problem that a large backflow occurs around the tongue between the front panel and the back panel and the impeller when the static pressure of the blower increases, and improvement in the efficiency of the impeller by energy saving is required. ing.
[0007]
The present invention solves such a conventional problem, and can improve the characteristics of the impeller by suppressing a decrease in blower efficiency due to a backflow between the front panel and the impeller generated when the blower is under pressure. When the clearance between the back panel and the impeller is large, the characteristics of the impeller can be improved by suppressing the back flow that flows to the back side of the impeller with low pressure. Also, the tongue height between the front panel and the impeller, the impeller It is an object of the present invention to provide a multiblade blower capable of optimizing the height of the tongue and the height of the tongue between the back panel and the impeller and further improving the characteristics at high static pressure.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, the multiblade fan of the present invention has an impeller having a plurality of blades attached so as to be sandwiched between a main plate and a side plate, and a spiral airflow around the impeller starting from a tongue. A scroll casing is formed so as to sandwich the spiral ventilation path by a front panel having a bell mouth-shaped suction port on the side plate side of the impeller and a back panel having no suction port. The front auxiliary tongue tongue radius of curvature R1 between the front panel and the impeller is smaller than the main tongue radius of curvature R2 of the impeller portion in the tongue shape, and the front panel and the front auxiliary tongue height between the impeller higher than the main tongue height of the impeller portion, the main tongue of the impeller portion back auxiliary tongue radius of curvature R3 of between the back panel and the impeller Smaller than the rate the radius R2, the main tongue curvature radius of the impeller portion is reduced to the shroud side from the main plate side, from the main tongue height of the impeller portion auxiliary tongue height between the back panel and the impeller It is something to raise.
[0011]
ADVANTAGE OF THE INVENTION According to this invention, when the clearance between a back panel and an impeller is large, the multiblade fan which can improve the characteristic of an impeller by suppressing the backflow which flows into the impeller back side with a low pressure is obtained.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
The present invention forms an impeller having a plurality of blades attached so as to be sandwiched between a main plate and a side plate, and forms a spiral air passage around the impeller starting from a tongue, and the side plate side of the impeller A scroll casing is formed so as to sandwich the spiral air passage by a front panel having a bell mouth-shaped suction port and a back panel having no suction port, and includes a shaft for applying a rotational force to the main plate, The front auxiliary tongue tongue radius of curvature R1 between the front panel and the impeller is smaller than the main tongue radius of curvature R2 of the impeller portion in the shape of the part, and the front auxiliary tongue height between the front panel and the impeller is was higher than the main tongue height of the impeller portion, to reduce the back auxiliary tongue radius of curvature R3 of between the back panel and the impeller from the main tongue radius of curvature R2 of the impeller portion, the impeller Of the main tongue radius of curvature smaller the shroud side from the main plate side, which has higher than the main tongue height of the impeller portion back auxiliary tongue height between the back panel and the impeller, the high static pressure time In the scroll casing, the reverse flow caused by the pressure difference between the back side of the impeller and the back panel is made difficult to flow by increasing the tongue height between the back panel and the impeller, reducing the back flow and suppressing the decrease in blower efficiency. Have.
[0017]
Embodiments of the present invention will be described below with reference to the drawings.
[0018]
【Example】
( Reference Example 1)
The same parts as those in the conventional example are denoted by the same reference numerals, and detailed description thereof is omitted.
[0019]
As shown in FIGS. 1 to 4, an impeller 104 having a plurality of blades 104 </ b> A attached so as to be sandwiched between a main plate 110 and a side plate 109, and a spiral shape starting from a tongue 111 around the impeller 104. Scroll so that the spiral air passage 102A is sandwiched between the front panel 102B in which the air passage 102A is formed, the front panel 102B having the bell mouth shape 113 suction port 105 provided on the side plate 109 side of the impeller 104, and the back panel 102C having no air suction port. A casing 102 is formed, and includes a shaft 103A for applying a rotational force to the main plate 110. In the tongue portion 111, the tongue radius of curvature R1 between the front panel 102B and the impeller 104 is smaller than the tongue radius of curvature R2 of the impeller 104 portion. The height of the front auxiliary tongue 1 between the front panel 102B and the impeller 104 is set to the main tongue 2 of the impeller 104. And has a configuration to be higher than that of.
[0020]
With the above configuration, in order to make the back flow 112 generated due to the pressure difference between the outer periphery of the impeller 104 and the pressure difference between the front panel 102B and the impeller 104 within the scroll casing 102 difficult to flow by increasing the height of the front auxiliary tongue 1, The characteristics of the impeller 104 can be improved by suppressing a decrease in blower efficiency due to the backflow 112 between the front panel 102B and the impeller 104 that is generated when the blower is under pressure.
[0021]
In the reference example was used multiblade blower which equal to the side plate 109 side tongues 111 radius of curvature from the main plate 110 side of the impeller 104, has a small tongue 111 radius of curvature from the main plate 110 side to the side plate 109 side A multiblade fan may be used, and there is almost no difference in its effect.
[0022]
(Example 1 )
This will be described with reference to FIG. 5 (Reference Example 2) and FIG. 6 (Example 1) .
[0023]
In addition, the same number is attached | subjected to the same location as a prior art example and a 1st reference example, and detailed description is abbreviate | omitted.
[0024]
As shown in the figure, the tongue 111 radius of curvature R3 between the back panel 102C and the impeller 104 is made smaller than the tongue 111 radius of curvature R2 of the impeller 104, and the back auxiliary tongue between the back panel 102C and the impeller 104 is obtained. 3 height is made higher than the main tongue part 2 height of the impeller 104 part.
[0025]
With the above configuration, the back flow 112 that flows between the back panel 102 </ b> C and the impeller 104 to the back side of the impeller 104 with low pressure is less likely to flow by increasing the height of the back auxiliary tongue 3. The characteristics of the impeller 104 can be improved by suppressing a decrease in blower efficiency due to 102C and the backflow 112.
[0026]
In Reference Example 2, a multiblade fan having the same tongue 111 radius of curvature from the main plate 110 side to the side plate 109 side of the impeller 104 was used, but in Example 1, the tongue 111 curvature radius was changed from the main plate 110 side to the side plate. Use a multi-blade fan reduced to the 109 side.
[0027]
( Reference Example 3)
This will be described with reference to FIG.
[0028]
In addition, the same number is attached | subjected to the same location as a prior art example and a 1st reference example, and detailed description is abbreviate | omitted.
[0029]
As shown in the figure, the tongue 111 radius of curvature between the front panel 102B and the impeller 104 R1, tongue 111 of curvature radius R2 of the impeller 104 parts, the back panel 102C and the tongue 111 radius of curvature between the impeller 104 R3, the outer diameter of the impeller 104 is D, the height of the front auxiliary tongue 1 between the front panel 102B and the impeller 104 is A1, the height of the main tongue 2 of the impeller 104 is A2, the back panel 102C and the impeller When the height of the back auxiliary tongue 3 between the vehicles 104 is A3, relationships of 0.475D <A1 <0.49D, 0.4D <A2 <0.475D, and 0.475D <A3 <0.49D are established. It has a configuration.
[0030]
With the above configuration, the height of the front auxiliary tongue 1 between the front panel 102B and the impeller 104, the height of the main tongue 2 of the impeller 104, and the height of the back auxiliary tongue 3 between the back panel 102C and the impeller 104 are as follows. It is possible to optimize and further improve the characteristics at high static pressure.
[0031]
【The invention's effect】
As apparent from the above examples, according to the present invention, to improve the characteristics of the impeller by suppressing the lowering of the blower efficiency due backflow between the front panel and the impeller blower occurs when the pressure, the back panel and the blade The multiblade fan which improves the characteristic of an impeller by suppressing the backflow which flows into the impeller back side with a low pressure between cars can be provided.
[Brief description of the drawings]
[Fig. 1] Side view of Reference Example 1 [Fig. 2] Front view of the same [Fig. 3] Characteristics of the same air volume-static pressure and air volume-efficiency [Fig. 4] Side view of other reference examples [Fig. 5] Reference Side view of Example 2 [Fig. 6] Side view of Example 1 of the present invention [Fig. 7] Front view of Reference Example 3 [Fig. 8] Perspective view of a conventional multi-blade fan [Fig. Explanation of]
DESCRIPTION OF SYMBOLS 1 Front auxiliary tongue part 2 Main tongue part 3 Back auxiliary tongue part 101 Multi-blade fan main body 102 Scroll casing 102A Ventilation path 102B Front panel 102C Back panel 103 Electric motor 103A Shaft 104 Impeller 104A Blade 105 Suction port 106 Discharge port 107 Air 108 Outer periphery 109 Side plate 110 Main plate 111 Tongue 112 Back flow 113 Bell mouth shape

Claims (1)

An impeller having a plurality of blades attached so as to be sandwiched between a main plate and a side plate, and a spiral air passage is formed around the impeller starting from a tongue, and a bell mouth shape is formed on the side plate side of the impeller A scroll casing is formed so as to sandwich the spiral ventilation path by a front panel having a suction port and a back panel having no suction port, and includes a shaft for applying a rotational force to the main plate, The front auxiliary tongue tongue radius of curvature R1 between the front panel and the impeller is made smaller than the main tongue radius of curvature R2 of the impeller portion, and the front auxiliary tongue height between the front panel and the impeller is set as the impeller. higher than the main tongue height parts, the back auxiliary tongue radius of curvature R3 of between the back panel and the impeller smaller than the main tongue radius of curvature R2 of the impeller portion, the main of the impeller portion The section radius of curvature smaller the shroud side from the main plate side, multiblade blower back auxiliary tongue height between the back panel and the impeller was higher than the main tongue height of the impeller portion.

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