JP4068837B2 - Vortex blower - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a general-purpose vortex blower used for blowing air and the like, and more particularly, to a suitable vortex blower that emphasizes low noise and high efficiency.
[0002]
[Prior art]
Whirlflow blowers have been widely used as relatively small-capacity blowers, but in recent years, there has been an increasing demand for smaller, lighter, higher discharge pressures, particularly improved efficiency and lower noise. .
[0003]
FIG. 1 is a diagram showing a general cross-sectional structure of a conventional vortex blower.
In FIG. 1, 1 is an induction motor, 2 is a blower (vortex blower), 3 is a rotation shaft of the induction motor 1, 4 is an impeller of the vortex blower, 5 is a blade of an impeller 4, and 6 is an impeller 4 , 7 is a blade casing of the impeller 4, 8 is a casing of the vortex blower, 9 is a boosting passage of the casing 8, 10 is a suction port of the vortex blower, 11 is an outlet of the vortex blower, and 12 is a cover of the vortex blower , 13 is an end cover of the vortex blower.
[0004]
As shown in FIG. 1, the blower portion 2 of the vortex blower mainly includes an impeller 4 and a casing 8, and the blade casing 7 of the impeller 4 is directly attached to the rotating shaft 3 of the induction motor 1. 4 is rotationally driven by the induction motor 1.
[0005]
The casing 8 is provided with a boosting path 9 that serves as a ventilation path. The boosting path 9 has an arc shape centered on the rotation center of the impeller 4, that is, the center line C of the rotation shaft 3 of the induction motor 1. It is formed and opened in a direction parallel to the center line C of the rotating shaft 3, and as shown in FIG. 1, the cross section is formed as a semicircular arc groove.
[0006]
As shown in FIG. 1, the impeller 4 includes a blade casing 7, an annular groove 6, and a blade 5.
The annular groove 6 formed in the blade casing 7 of the impeller 4 is formed as an annular groove having a concentric circle centered on the center line C of the rotary shaft 3 of the induction motor 1. A plurality of blades 5 are provided so as to delimit directions.
[0007]
The impeller 4 is attached to the rotary shaft 3 of the induction motor 1 so that the opening of the annular groove 6 of the blade casing 7 faces the casing 8 as shown in FIG. The casing 8 is attached to the induction motor 1 so that the open side of the boosting path 9 is directed to the impeller 4, and as a result, the casing 8 is positioned closer to the induction motor 1, while the impeller 4 is guided. That is, it is located away from the electric motor 1.
[0008]
Moreover, since the suction inlet 10 and the discharge outlet 11 are connected to the pressure | voltage rise path 9 of the casing 8, they are attached toward the induction motor 1 side.
[0009]
2 is a diagram showing a general structure of a conventional eddy current blower casing, FIG. 2 (a) is a front view of a main part of the conventional eddy current blower casing, and FIG. 2 (b) is a line c in FIG. 2 (a). FIG.
The blade 5 of the impeller 4 returns to the suction port 10 of the casing 8 again through the discharge port 11 from the suction port 10 of the casing 8 through the pressure increasing path 9 as the impeller 4 rotates.
In this process, the gas is given a pressure difference and is discharged from the discharge port 11 of the casing 8.
[0010]
At this time, in order to prevent the gas given a pressure difference from flowing into the suction port 10 of the casing 8, the casing 8 communicates with the pressure increasing path 9 as shown in FIGS. 2 (a) and 2 (b). A partition wall 14 for separating the suction port 10 and the discharge port 11 is provided.
The partition wall 14 of the casing 8 seals pressure by a labyrinth structure.
[0011]
Usually, in an eddy current blower, the area of the space | interval for 2 to 3 blades 5 of the impeller 4 is secured.
However, the volume which is constituted by the cross-sectional area of the blade 5 of the impeller 4 and the annular groove 6 of the blade casing 7 is such that the gas given a pressure difference in the vicinity of the discharge port 11 of the casing 8 passes through the partition wall 14 of the casing 8. A so-called carry-over, which flows into the suction port 10 beyond, has occurred, and this has been an impediment to improving the blowing efficiency of the vortex blower.
[0012]
Further, the gas that has been given a pressure difference carries over, and the gas that has carried over in the vicinity of the suction port 10 of the casing 8 is suddenly opened, which is one of the causes of noise generation in the vortex blower.
[0013]
[Problems to be solved by the invention]
In the conventional technique, a gas having a pressure difference in the vicinity of the discharge port 11 of the casing 8 carries over the partition wall 14 of the casing 8 and easily flows into the suction port 10 of the casing 8. Improves ventilation efficiency and reduces noise.
[0014]
The present invention can solve the above-mentioned problem by reducing the amount that the gas given a pressure difference near the discharge port 11 of the casing 8 carries over the partition wall 14 of the casing 8 to the suction port 10. is there.
[0015]
The object of the present invention is to cope with the above-mentioned problems, and the carry-over suppression body provided on the blade of the impeller and the partition wall of the casing reduces the volume of the space between the blades of the impeller, and the rotation of the impeller. The carryover suppressor reduces the carryover amount of the gas that is given a pressure difference near the discharge port of the casing and flows into the suction port beyond the partition wall of the casing, improving the blowing efficiency of the vortex blower, The carry-over amount of gas given the pressure difference flowing from the discharge port of the casing to the suction port is less than that of the conventional vortex blower, reducing the noise of the vortex blower, reducing the noise and improving the efficiency of the vortex blower. It is to provide a vortex blower that can be achieved.
[0016]
[Means for Solving the Problems]
The vortex blower of the present invention includes an impeller in which a plurality of blades are provided in an annular groove having a substantially semicircular cross section formed in a blade casing, and an arc-shaped ventilation path facing the annular groove of the blade casing of the impeller In a vortex blower having a blower portion comprising a combination with a casing provided with a partition that separates a suction port and a discharge port communicating with the ventilation path in the casing, at a position that does not act on gas pressure, a recess provided in the blade, and wherein the correspondence with the recess in the casing of the bulkhead comprises a projection and which is provided, to reduce the volume of the space between the front Kivu blade covered with the partition wall It has the composition to do.
[0017]
The eddy current blower of the present invention is characterized in that the shape of the concave portion and the protrusion is a semicircular arc shape or a square shape corresponding to each shape.
[0018]
The vortex blower of the present invention is characterized in that the concave portion and the protrusion are provided in the vicinity of the center on the open side of the blade.
[0019]
According to the present invention, in the blower portion 2 of the vortex blower, the shape of the blade 5 of the impeller 4 is provided with a notch recess, and the partition wall 14 of the casing 8 is also provided with a protrusion at a corresponding location, whereby the casing By reducing the amount of gas that is given a pressure difference in the vicinity of the eight discharge ports 11 over the partition wall 14 of the casing 8 and flows into the suction port 10, the noise and the efficiency of the vortex blower are reduced. Can be achieved.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
The vortex blower of the present invention is opposed to the impeller 4 provided with a plurality of blades 5 in the annular groove 6 formed in the blade casing 7 and having a substantially semicircular cross section, and the annular groove 6 of the blade casing 7 of the impeller 4. A blower portion 2 comprising a combination with a casing 8 provided with a booster passage 9 serving as an arcuate ventilation passage is provided, and the casing 8 has a partition wall that separates the suction port 10 and the discharge port 11 communicating with the booster passage 9. 14 is formed, and the carry-over suppressing body 15 that reduces the volume of the space between the blades 5 of the impeller 4 is provided on the blade 5 of the impeller 4 and the partition wall 14 of the casing 8.
[0021]
In the vortex blower of the present invention, a carry-over suppressing body 15 is provided in a semicircular notch recess 5a provided on the blade 5 of the impeller 4, and a semicircular arc notch of the blade 5 of the impeller 4 on the partition wall 14 of the casing 8. It consists of the semicircular arc-shaped protrusion 14a provided corresponding to the recessed part 5a.
[0022]
The vortex blower of the present invention is provided at a position where the carry-over suppressing body 15 does not act on the gas pressurization of the blade 5 of the impeller 4 and the partition wall 14 of the casing 8.
[0023]
FIG. 3 is an explanatory view showing a part of the vortex blower in the embodiment of the present invention, FIG. 3 (a) is an enlarged sectional view of a main part of the vortex blower in the embodiment of the present invention, and FIG. 3 (b) is the present invention. It is a principal part expanded sectional view of the eddy current blower in other embodiment.
As shown in FIG. 3A, the plurality of blades 5 attached to the impeller 4 are provided with a semicircular notch recess 5a, and the partition wall 14 of the casing 8 is provided with the blade 5 of the impeller 4. A semi-arc-shaped protrusion 14a is provided at a location corresponding to the semi-arc-shaped notch recess 5a.
[0024]
The principle of the vortex blower is that when the impeller 4 rotates, a plurality of blades 5 of the impeller 4 gives kinetic energy to the gas by a radial force and a rotational force due to centrifugal force.
As a result, the accelerated gas swirls along the arcuate pressure increase path 9 of the casing 8, increases the pressure by the recovery of the static pressure, and flows into the impeller 4 again.
The gas flow at this time performs a combined swivel motion of the arc of the casing 8 and the impeller 4 and the circumferential direction.
[0025]
The blowing efficiency of the vortex blower is as low as 35-40% compared to 60-90% of the blowing efficiency of other blowers, for example, turbo blowers.
One of the factors is that gas having a pressure difference flows from the discharge port 11 to the suction port 10 through the partition wall 14 of the casing 8, that is, gas carryover.
This carry-over amount is the amount of gas that does not work to the outside in response to the supply of kinetic energy due to the rotational movement of the impeller 4 due to the turning motion, and reducing this carry-over amount is the blowing efficiency of the vortex blower Greatly contributes to improvement.
[0026]
From the principle of pressure increase by swirling motion of the vortex blower, the gas is not necessarily pressurized using the entire area of the blade 5 of the impeller 4 at the stage of giving a pressure difference to the gas. When 5 is a two-dimensional shape, the vicinity of the center on the open side of the flat blade 5 hardly affects the gas pressurization.
Therefore, a semicircular notch recess 5a is provided at an appropriate position not acting on the gas pressure of the blade 5, and a semicircular projection corresponding to the semicircular notch recess 5a of the blade 5 is provided in the partition wall 14 of the casing 8. There is almost no decrease in the blowing efficiency of the vortex blower due to the provision of 14a.
[0027]
On the other hand, in the process in which the impeller 4 rotates and moves from the discharge port 11 of the casing 8 to the suction port 10 through the partition wall 14, a gas having a pressure difference in the vicinity of the discharge port 11 of the casing 8 is supplied to the casing 8. The amount of gas carried over to the suction port 10 beyond the partition wall 14 is determined by the area constituted by the blade 5 and the volume formed by the annular groove 6 of the blade casing 7.
[0028]
Therefore, as described above, the blade 5 of the impeller 4 is provided with the semicircular arc-shaped notch recess 5a, and the partition 14 of the casing 8 is provided with the semicircular arc-shaped protrusion 14a. And the volume formed by the annular groove 6 of the blade casing 7 is reduced, so that it is composed of a semicircular notch recess 5 a provided in the blade 5 and a semicircular protrusion 14 a provided in the partition 14 of the casing 8. The carryover suppressing body 15 suppresses the carryover of the gas, and the amount of the gas that is given a pressure difference near the discharge port 11 of the casing 8 carries over to the suction port 10 beyond the partition wall 14 of the casing 8. It is possible to reduce the decrease in the blowing efficiency of the vortex blower.
[0029]
Further, as a cause of noise generation from the impeller 4 of the vortex blower, it can be mentioned that the pressure of the gas at the suction port 10 and the discharge port 11 of the casing 8 is changed.
This is because the pressure difference between the gas provided with the pressure difference carried by the carry-over and the gas in the vicinity of the suction port 10 of the casing 8 causes a sudden gas movement, which is converted into sound energy. This generates noise.
[0030]
Therefore, the smaller the pressure difference, the lower the noise, and the smaller the amount of gas having the pressure difference, the smaller the energy.
Therefore, the noise of the vortex blower can be reduced by reducing the amount by which the gas having a pressure difference near the discharge port 11 of the casing 8 carries over the partition wall 14 of the casing 8 to the suction port 10. Is possible.
[0031]
In addition to the semicircular arc notch recess 5a shown in FIG. 3 (a), the shape of the notch recess provided in the blade 5 of the impeller 4 is a square notch recess 5b as shown in FIG. 3 (b). Alternatively, an arbitrary curve, straight line, or polygonal shape may be used.
[0032]
On the other hand, the shape of the protrusion provided on the partition wall 14 of the casing 8 corresponding to the notch recess of the blade 5 of the impeller 4 is shown in FIG. 3B in addition to the semicircular arc-shaped protrusion 14a shown in FIG. In this manner, the rectangular protrusion 14b may be used, or an arbitrary curve, straight line, or polygonal shape may be used.
[0033]
Furthermore, the position where the notch recess and the protrusion are provided in the blade 5 of the impeller 4 and the partition wall 14 of the casing 8 is not only near the center on the open side of the blade 5 as shown in FIGS. When the blade 5 of the impeller 4 has a three-dimensional shape, it is necessary to provide the blade 5 at a position that does not affect the pressure corresponding to the gas corresponding to the curved surface of the blade 5.
[0034]
FIG. 4 shows an example of a comparison between the vortex blower of the present invention and a conventional vortex blower.
FIG. 4 is an air flow-efficiency characteristic diagram conceptually showing the efficiency when the air flow of the vortex blower in the embodiment of the present invention is changed.
In FIG. 4, a dotted line shows a conceptual curve of the efficiency of the eddy current blower having the conventional structure, and a solid line shows a conceptual curve of the efficiency of the eddy current blower having the structure to which the present invention is applied.
In FIG. 4, ΔY represents an improvement in efficiency according to the present invention.
The blowing efficiency of the vortex blower having the structure to which the present invention is applied is improved by ΔY as compared with the blowing efficiency of the vortex blower having the conventional structure, as shown in FIG.
[0035]
【The invention's effect】
According to the vortex blower of the present invention, since the carry-over suppressing body provided on the blade of the impeller and the partition wall of the casing reduces the volume of the space between the blades of the impeller, the discharge port of the casing is accompanied with the rotation of the impeller. The carry-over suppressor can reduce the carry-over amount of the gas that flows into the suction port over the partition wall of the casing due to the pressure difference in the vicinity, improving the blowing efficiency of the vortex blower The carry-over amount of the gas with the pressure difference flowing from the discharge port to the suction port is less than that of the conventional vortex blower, so the noise of the vortex blower can be reduced, the noise of the vortex blower is reduced, and the efficiency is high Can be achieved.
[0036]
According to the vortex blower of the present invention, the carry-over suppressing body includes the notch recess provided in the blade of the impeller and the projection provided in the partition of the casing corresponding to the notch recess of the blade of the impeller. A low-noise and high-efficiency vortex blower can be provided simply by separately providing notched recesses and protrusions on the blade and casing partition walls.
[0037]
According to the vortex blower of the present invention, the carryover suppressing body is provided at a position where the carryover suppressing body of the vortex blower does not act on the gas pressure of the blade of the impeller and the partition wall of the casing. There is not much.
[Brief description of the drawings]
FIG. 1 is an explanatory view showing a general cross-sectional structure of a conventional vortex blower.
FIG. 2 is an explanatory view showing a general structure of a casing of a conventional vortex blower.
FIG. 3 is an explanatory view showing a part of the vortex blower in the embodiment of the present invention.
FIG. 4 is an air flow-efficiency characteristic diagram conceptually showing the efficiency when the air flow of the vortex blower in the embodiment of the present invention is changed.
[Explanation of symbols]
1 Induction motor 2 Blower (vortex blower)
3 Rotating shaft 4 Impeller 5 Blade 5a Semi-circular cutout recess 5b Square cutout recess 6 Annular groove 7 Blade casing 8 Casing 9 Booster passage 10 Suction port 11 Discharge port 12 Cover 13 End cover 14 Bulkhead 14a Semicircular arc-shaped projection 14b Square shape Protrusion 15 Carryover suppressor C Center line

Claims (3)

A set of an impeller in which a plurality of blades are provided in an annular groove having a substantially semicircular cross-sectional shape formed in a blade casing, and a casing in which an arc-shaped ventilation path facing the annular groove of the blade casing of the impeller is provided. In a vortex blower comprising a blower portion comprising a combination, and forming a partition separating the suction port and the discharge port communicating with the ventilation path in the casing,
In a position where it does not act on the pressure of the gas, provided with a recess provided on the blade, and a protrusion provided on the partition wall of the casing corresponding to the recess,
Vortex blower, characterized in that to reduce the volume of the space between the front Kivu blade covered with the partition wall. The shape of the said recessed part and the said protrusion is a semicircular arc shape or square shape according to each shape, The eddy current blower of Claim 1 characterized by the above-mentioned. 3. The vortex blower according to claim 1 , wherein the recess and the protrusion are provided in the vicinity of the center of the open side of the blade .

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