JPH05240192A - Vortex pump - Google Patents

Abstract

PURPOSE:To improve aerodynamic performance by forming the shape of the reverse side of an impeller into a proper three-dimensional form to the blade back side or the rotating direction so that the inner circumferential side of the impeller can be conformed to a high speed relative flow. CONSTITUTION:An impeller 1 is formed of a hub 9 and a number of blades 5. When the cylindrical surface connecting the inside point of the blade 5 and parallel to the axis is R1, the circle connecting the outside end is R2, the circle connecting the center between the inside end and the outside end is Rc, and the circle connecting the center between R1 and Rc is Ri, the position of the front edge of the blade on the circumference of Rc is behind the inside end, when seen in the rotating direction of the blade. When the axial inlet angle of the blade rear end on the circumference of Ri is gammai, and the axial inlet angle on the circumference of Rc is gammaC, both gammai and gammac are smaller than 90 deg., and gammaj and gammac have different values. Since the blade form is determined to such a three-dimensional form, thus, the aerodynamic performance can be improved by far, compared with a conventional one.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vortex pump suitable for use in a vortex gas pump such as a vortex blower or a vortex liquid pump such as a Wesco pump.

[0002]

2. Description of the Related Art A vortex pump is characterized by its small size and high static pressure. In order to further enhance this feature, various proposals and studies have been made in the past.

For example, the Japan Society of Mechanical Engineers, Vol. 45, 39
On pages 1107 to 1106 of No. 6 (Showa 54.8), when the radius of the circle connecting the inner ends of the blades is R1 and the radius of the circle connecting the outer ends is R2, the values of R1 / R2 are changed. It is described that the characteristics of the eddy-flow blower (discharge flow rate-discharge pressure characteristic) change.

According to this, the value of 0.68 is higher than that of 0.82 in both the flow coefficient and the pressure coefficient, and is 0.
75 has been shown to be even higher.

However, in terms of the flow rate and the pressure, when the value of R2 is constant, the higher the value of R1 / R2 is, the higher the pressure is and the smaller the flow rate is.
When the value of 2 is decreased, the flow rate is increased and the pressure is decreased.

In order to reduce the size of the vortex blower, it is sufficient to reduce the value of R2, but if the value is simply reduced,
The pressure drops and the flow rate decreases.

On the other hand, it has been proposed to improve the aerodynamic performance of the vortex flow blower by devising the shape of the blade. JP-A-49-105220, JP-A-49-120209
The one disclosed in Japanese Patent Publication has a blade with an axial inlet angle and outlet angle of 9
It is designed to be smaller or larger than 0 degree to improve aerodynamic performance. Further, Japanese Utility Model Laid-Open No. 52-170309 discloses a radial inlet angle smaller than 90 degrees.

[0008]

Since the vortex flow pump has the advantage of being able to provide a fluid with a high static pressure, its application has been expanded in recent years, and accordingly, a higher static pressure or a conventional pressure may be used. There is a strong demand for further miniaturization.

However, in the conventional techniques including the above-mentioned conventional technique, a predetermined pressure is maintained to further reduce the size,
Alternatively, it has been difficult to significantly increase the pressure without increasing the size.

Further, the conventional vortex pump has a problem that it is noisy, which has been a cause to prevent its application to those used in a quiet environment such as medical equipment.

The present invention has been made in view of the above points, and an object of the present invention is to provide a vortex pump capable of significantly improving aerodynamic performance as compared with a conventional one. is there.

Another object of the present invention is to provide a vortex pump having low noise.

[0013]

In order to achieve the above object, in the present invention, firstly, at least on the inner peripheral side of the impeller, the blade back side, that is, the rotating direction, so as to be able to cope with a high-speed relative flow. On the other hand, the shape of the back side should be an appropriate three-dimensional shape.

That is, R1 is a cylindrical surface connecting the inner ends of the blades and parallel to the axis, R2 is a circle connecting the outer ends, Rc is a circle connecting the centers of the inner and outer ends, and the center of R1 and Rc is the center. When the connecting circle is Ri, the position on the circumference of Rc of the leading edge of the blade is behind the inner end when viewed in the rotation direction of the blade, and the circle of Ri on the trailing edge of the blade is also behind. When the axial inlet angle on the circumference is γi and the axial inlet angle on the circumference of Rc is γc, both γi and γc are smaller than 90 degrees, and γi
And γc are configured to have different values.

Secondly, in the present invention, the inter-blade cross-sectional area of the impeller is reduced from R1 to Ri so that it is 50 m.
Prevents separation of the fluid entering between the blades at a high speed of at least / sec. That is, the intersection of two blades adjacent to Rc is obtained, and a plane having a straight line passing through the intersection as a rotation axis is
Regarding the area between the blades, the area of a cross section A1 passing through the intersection of R1 and the blade back side hub surface, the area of the cross section Ai passing through the intersection of Ri and the blade back side hub surface, and A1 and Ai having the same rotation axis The area of the cross section Ar located in the middle of
It is characterized in that at least a part of the cross-sectional area is reduced with respect to the linear interpolation between the area of 1 and the area of Ai.

[0016]

A casing is made of a transparent material so that the inside of the arcuate flow path can be observed from the outside, and the flow of the fluid flowing through the arcuate flow path is observed.

That is, as shown in FIGS. 25, 26, 27, and 28, when the outer end of the blade 5 is 5a, the inner end 5b and the center thereof are 5c, the arc-shaped flow path from the suction port 6a. The air entering the inside of 8 is the air against the speed of the blades 5,
The velocity distribution along the arcuate flow path 8 has a positive value from the outer end 5a to the center 5c, but from the center 5c to the inner end 5a, as shown in FIGS. It is to show a negative value.

As shown in FIG. 29, the velocity distribution flowing across the arcuate flow path 8 shows a positive value from the outer end 5a to the center 5c and a negative value from the center 5c to the inner end 5b. Indicating a value was already known.

As a result, the arrow 7 in FIG.
As indicated by 0, it has been found that the inner edge 5b is slightly returned with respect to the rotation direction F. Conventionally, it has been considered that the air flow simply advances gradually in the rotation direction F while drawing a spiral as shown by an arrow 80.

Therefore, in the present invention, the radial inlet angle of the blades 5 and the axial direction are adjusted so that the velocity of the air along the arcuate flow path and the composite vector of the velocity components flowing in the direction of traversing the arcuate flow path 8 are matched. Since the inlet angle is set and the blade shape is set in a three-dimensional shape, the aerodynamic performance is much improved as compared with the conventional one.

Further, by providing the inter-blade cross-sectional area reducing means of the present invention, since the high-speed incident flow is contracted and does not separate when taken in between the blades from the inner peripheral side, generation of a sound source can be suppressed, The noise level is low.

[0022]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 5, 1 is an impeller, and 2 is a casing forming an arcuate flow path 8. The arcuate flow path 8 has a groove shape that opens in a direction parallel to the axis of the rotating shaft 3. The arcuate flow path 8 is formed in an arcuate shape centered on the rotation shaft 3 of the prime mover 4. One end of the arcuate flow path 8 communicates with the suction port 6a and the other end communicates with the discharge port 6b. The impeller 1 extends from the discharge port 6b to the suction port 6a.
It is partitioned by a partition wall 10 which is opposed to each other through a minute void. Suction side passage 6a 'and discharge port 6b connected to the suction port 6a
The discharge port side passage 6b 'connected to the above is provided parallel to the inside of the muffler 7 which also serves as the base member. The prime mover 4 is fixed on a silencer 7 which also serves as a base member, and the casing 2 is fixed to the prime mover 4.

The impeller 1 is composed of a hub 9 and a large number of blades 5 as shown in FIGS. 1 to 3, and the hub 9 is fixed to a rotary shaft 3 of a prime mover 4. Of these, the hub 9 has an annular groove 11 centering on the rotary shaft 3 and opening in the axial direction so as to oppose the arcuate flow path 8, and a large number of blades 5 are provided in a direction crossing the groove 11. ..

Here, the terms and symbols of each part of the impeller 1 will be collectively described. R1 ′: radius of a circle connecting the inner ends of the blades 5. R2 ': radius of a circle connecting the outer ends of the blades 5. Rc ': radius of a circle having a radius of 1/2 of R1' + R2 '. Ro ': radius of a circle having a radius of 1/2 of Rc' + R2 '. Ri ′: Radius of a circle whose radius is half of R1 ′ + Rc ′. R1: A circle having a radius R1 ′ centered on the axis of the rotary shaft 3. R2: A circle having a radius R2 ′ centered on the axis of the rotating shaft 3. Rc: A circle having a radius Rc ′ centered on the axis of the rotating shaft 3. Ro: A circle having a radius Ro ′ centered on the axis of the rotating shaft 3. Ri: A circle having a radius Ri 'centered on the axis of the rotating shaft 3. β1: radial entrance angle, formed by a tangent to the circle R1 and a straight line connecting the circumferential position of R1 and the circumferential position of Rc at the trailing edge (tip in the axial direction) of the blade 5 Complementary to the horn. β2: Radial exit angle, which is formed by a tangent to the circle R2 and a straight line connecting the circumferential position of R2 and the circumferential position of Rc at the trailing edge (tip in the axial direction) of the blade 5. Complementary to the horn. γ1: axial entrance angle on the circumference of circle R1,
The angle formed near the trailing edge of the blade with respect to the plane connecting the trailing edges of the blades 5. γi: an axial entrance angle on the circumference of the circle Ri,
The angle formed near the trailing edge of the blade with respect to the plane connecting the trailing edges of the blades 5. γc: Axial entrance angle on the circumference of circle Rc,
The angle formed near the trailing edge of the blade with respect to the plane connecting the trailing edges of the blades 5. γo: Axial exit angle on the circumference of circle Ro,
The angle formed near the trailing edge of the blade with respect to the plane connecting the trailing edges of the blades 5. γ2: Axial exit angle on the circumference of circle R2,
The angle formed near the trailing edge of the blade with respect to the plane connecting the trailing edges of the blades 5. Is.

As shown in FIGS. 3 and 4, the impeller shown in FIG. 1 has a smaller γc than γo and γi.

The radial entrance angle β is smaller than 90 degrees.

The air entering the arcuate flow path 8 through the suction port 6a has a velocity distribution along the arcuate flow path 8 of the air with respect to the velocity of the blades 5, as described above. 29
In particular, as shown in FIG. 28, the outer end 5a to the center 5c show a positive value, and the vicinity of the center 5c to the inner end 5b show a negative value.

As shown in FIG. 29, the velocity distribution flowing across the arcuate flow path 8 is from the outer end 5a to the center 5 as shown in FIG.
A positive value is shown up to the vicinity of c, and the center 5c to the inner end 5
It has already been described that it shows a negative value up to a.

The speed triangle of the impeller here is shown in FIG. Where Wo, Wc1, Wc2,
Wi is the relative velocity of the air with respect to the blade 5 near the circumference of Ro, Rc, Rc, and Ri, Uo, Uc1, and Uc, respectively.
2, Ui are peripheral speeds of the blades 5 in the vicinity of the circumferences of Ro, Rc, Rc, and Ri, and Co, Cc1, Cc2, and Ci are:
These are absolute velocities of air near the circumferences of Ro, Rc, Rc, and Ri, respectively. Here, the reason why two velocity triangles are drawn in the vicinity of the circumference of Rc is that the air flow direction is reversed slightly outside the circumference as shown in FIG. The flow is illustrated.

In this embodiment, the magnitudes of γo and γc1 are
The angle between Uo and Wo and the angle between Uc1 and Wc1 are also shown. Therefore, in this embodiment, the radial entry angle of the blade 5 is adjusted so that the relative velocity of the air, that is, the velocity of the air along the arc-shaped channel 8 and the combined vector of the velocity components flowing in the direction traversing the arc-shaped channel 8 are matched. Further, since the axial inlet angle is set and the blade shape is set in the three-dimensional shape, the aerodynamic performance is much improved as compared with the conventional one.

FIG. 7 shows a dimensionless performance comparison with the conventional example when the value of β1 is 90 degrees and the value of γ is 22 to 50 degrees.

The quantities of the conventional example are β1, β2, γc and γ
All o are 90 degrees. Further, γc when the performance of the example of the present invention is obtained is set to a value that is 13 degrees smaller than γi. The value of β2 is 90 degrees, and the value of R1 / R2 is 0.5
It was fixed at 8. FIG. 8 shows that the radial inlet angle β1 is 20 degrees and 90 degrees.
The relationship between the flow coefficient and the pressure coefficient when the degree is selected is shown. From this figure, it can be seen that when the radial inlet angle β1 is 20 degrees, both the flow coefficient and the pressure coefficient are larger than when they are 90 degrees. 9-12 are different embodiments of the present invention. In this embodiment, the axial inlet angle γi has a value smaller than 90 degrees, and this state continues up to the root contacting the hub. The sectional area of each part corresponds to the inclination angle α in FIG. It changes like. According to this embodiment, as shown in FIG. 6, the relative velocity wi incident from the inner circumference side
For example, when Ri is 65 mm, it is as large as 50 m / sec or more, but Ai is smaller than A1 or Ac and the width on the hub side is smaller than the tip of the axial splash, so that a contracted flow does not occur and separation does not occur. Therefore, blockage does not occur, so the inflow is smooth, and there are the effects of improving aerodynamic performance and reducing noise. 13 to 16 are corresponding conventional examples, and as shown in FIG. 15, since the cross-sectional area continuously increases from A1 to A2, separation occurs and flow smoothness is impeded.

17 to 19 show another embodiment,
The performance is improved and the pressure coefficient is 16 or more to prevent separation due to contraction.

20 to 21 show still another embodiment of the present invention. In this embodiment, it is not covered by the hub 9. The blades 5 are provided on both sides of the hub, respectively. Also in this case, the inner end of the blade 5 is considered to be 5b, and the outer end is 5a.
Therefore, it is also possible to consider the intermediate value as 5c and to think in the same manner as that shown in FIGS. Even in this case β1
Is smaller than 90 degrees, and β2 is larger than 90 degrees. In this embodiment, γi is a value smaller than 90 degrees.

FIG. 22 shows still another embodiment. In this embodiment, by improving the vicinity of the tip of the blade on the ventral side and narrowing the hub side, it is possible to improve the performance by reducing the flow and reduce the noise level.

23 and 24 show still another embodiment,
Although the outer peripheral side of the blade 5 of the embodiment shown in FIG. 22 is not covered by the hub 9, similar improvement in performance and reduction in noise level can be obtained.

[0037]

As described above, according to the present invention, the combined vector of the velocity of the air flowing in the arc-shaped channel along the arc-shaped channel and the velocity component flowing in the direction crossing the arc-shaped channel is matched. As described above, since the radial inlet angle of the blade and the axial inlet angle are determined and the blade shape is determined in the three-dimensional shape, the aerodynamic performance is improved. Further, even though the incident relative flow is large, the flow path between the blades is reduced and blockage due to separation does not occur, so that the inflow is smooth and the aerodynamic performance is improved and the noise is reduced. Further, since the flow is not separated, wasteful energy is removed, so that noise can be suppressed from the sound source, so that the structure of the silencer can be simplified, and the calorific value can be reduced, so that cooling can be facilitated.

[Brief description of drawings]

FIG. 1 is a perspective view of an impeller, showing an embodiment of the present invention.

FIG. 2 is a plan view showing a part of the impeller shown in FIG. 1 in an enlarged manner.

FIG. 3 is a cross-sectional view showing FIG. 2 taken along line AA, line BB, and line CC.

FIG. 4 is a characteristic diagram showing changes in an axial inlet angle and an outlet angle of each part of the impeller shown in FIG.

FIG. 5 is a perspective view of a vortex flow blower showing an embodiment of the present invention.

6 is a diagram showing a velocity vector by the impeller shown in FIG.

FIG. 7 is a characteristic diagram showing experimental data of the example shown in FIG. 1 in comparison with conventional data.

FIG. 8 is a characteristic diagram showing the experimental data of the embodiment shown in FIG. 1 by changing the radial inflow angle β1.

FIG. 9 is a partially enlarged plan view showing another embodiment of the present invention.

10 is a cross-sectional view of FIG.

11 is a diagram showing an area change of a cross section corresponding to the inclination angle α in FIG.

12 is each sectional view of FIG.

FIG. 13 is a partially enlarged view showing a conventional example corresponding to the embodiment of FIG.

14 is a cross-sectional view of FIG.

FIG. 15 is a diagram showing an area change of a cross section corresponding to the inclination angle α in FIG.

FIG. 16 is a diagram showing each cross section of FIG. 13;

FIG. 17 is a perspective view of an impeller showing still another embodiment of the present invention.

FIG. 18 is a front view of the impeller shown in FIG.

19 is a sectional view of the impeller shown in FIG. 18, corresponding to FIG. 3;

FIG. 20 is a perspective view of an impeller showing still another embodiment of the blade of the present invention.

21 is a view corresponding to FIG. 3 of the impeller shown in FIG. 20.

FIG. 22 is a view corresponding to FIG. 3 of still another embodiment of the present invention.

FIG. 23 is a diagram showing still another embodiment of the present invention.

FIG. 24 is a sectional view corresponding to FIG. 3 in FIG. 23.

FIG. 25 is a diagram showing a state of air flowing in a direction crossing an arcuate flow path.

FIG. 26 is a diagram showing a state of air flowing along an arcuate flow path.

FIG. 27 is a diagram for explaining the flow of air in the arc-shaped channel.

FIG. 28 is a diagram showing a velocity distribution of air flowing along an arcuate flow path.

FIG. 29 is a diagram showing a velocity distribution of air flowing in a direction crossing an arcuate flow path.

[Explanation of symbols]

1 ... Impeller, 2 ... Casing, 3 ... Rotation axis, 5 ... Blade,
5a ... Blade outer end, 8 ... Arc-shaped flow path, 9 ... Hub.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshiharu Yoshitomi 1-1-1, Higashi Narashino, Narashino City, Chiba Prefecture Inside the Narashino Factory, Hitachi Ltd. (72) Inventor Kazuo Kobayashi 7-1, 1-1 Higashi Narashino, Narashino City, Chiba Prefecture Hitachi, Ltd. Narashino Factory (72) Inventor Shizuka Ishikawa 7-1-1 Higashi Narashino, Narashino City, Chiba Prefecture Hitachi Ltd. Narashino Factory (72) Inventor Yoshiaki Noda 7-1-1 Higashi Narashino, Narashino City, Chiba Prefecture Narashino Factory, Hitachi, Ltd.

Claims (9)

[Claims] 1. An arc-shaped flow path, a suction port and a discharge port communicating with the arc-shaped flow channel, and a space between the discharge port and the suction port through a minute gap with respect to a passage path of a blade. A partition wall, a hub fixed to the rotation shaft, and a large number of blades that rotate integrally with the hub along the arcuate flow path, the circle connecting the inner ends of the blades. R1,
When the circle connecting the outer ends is R2 and the circle connecting the center of the inner end and the outer end is Rc, Rc of the trailing edge of the blade is
On the circumference of the blade is behind the inner end in the rotation direction of the blade, and at the center Ri of the inner edge of the trailing edge of the blade and the circumference of Rc. When the axial inlet angle is γi and the axial inlet angle on the circumference of Rc is γc, both γi and γc are smaller than 90 degrees, and γi and γc have different values. A vortex pump characterized by being installed. 2. The vortex pump according to claim 1, wherein γc has a smaller value than γi. 3. The vortex flow according to claim 2, wherein the axial inlet angle of the blade gradually decreases as it approaches the circumference of the circle Rc from the circumference of the circle Ri. pump. 4. An arcuate flow path, a suction port and a discharge port communicating with the arcuate flow channel, and a minute gap between the discharge port and the suction port with respect to the passage path of the blade. An inner end of the blade, which has a partition wall through which the hub is fixed, a hub fixed to the rotating shaft, and a large number of the blades that rotate integrally with the hub along the arcuate flow path. Let R1 be a circle connecting the two, R2 be a circle connecting the outer ends, Rc be a circle connecting the centers of the inner end and the outer end, and Ri be a circle connecting the centers of the circumference of R1 and the circumference of Rc. At this time, the intersection between Rc and the back side tip of two adjacent blades is obtained, and in the plane having the straight line passing through the intersection as the axis of rotation, the area between the blades passes through the intersection between R1 and the blade back side hub surface. Area of cross-section A1 and area of cross-section Ai that passes through the intersection of Ri and the blade back side hub surface And an area of a cross section Ar having the same rotation axis and located in the middle of A1 and Ai is at least partly smaller than a linear interpolation between the area of A1 and the area of Ai. Eddy current pump. 5. The area of at least part of the cross section Ar is A
The swirl pump according to claim 4, wherein the swirl pump is smaller than 1. 6. A back side shape of a blade forming the cross section Ar is a cross section of a concentric cylindrical surface of R1 and Ri, and an axial angle is 90 degrees or less over the entire area from the blade tip to the root. A vortex pump according to item 4. 7. The vortex pump according to claim 4, wherein the axial angle is 90 degrees or less at least near the tip of the blade on the ventral side of the blade. 8. An arcuate flow path, a suction port and a discharge port respectively communicating with the arc-shaped flow channel, and a minute gap between the discharge port and the suction port with respect to the passage path of the blades. A partition having a partition wall, a hub fixed to a rotating shaft, and a large number of blades that rotate integrally with the hub along the arcuate flow path and connect the inner ends of the blades. Circle to R
1, R1 is a circle connecting the outer ends, Rc is a circle connecting the centers of the inner and outer ends, and Ri is a circle connecting the centers of the circumference of R1 and the circumference of Rc. The value of R2 is less than 0.68, the pressure coefficient is 14 or more, the radial inlet angle β1 of the trailing edge of the blade is less than 90 degrees, and the axis of the blade Ri at the trailing edge on the circumference of the circle is small. A vortex pump, wherein the directional inlet angle γ1 and the axial inlet angle on the circumference of the Rc are smaller than 90 degrees, and γi and γc are different from each other. 9. An arc-shaped flow path, a suction port and a discharge port which communicate with each other in the arc-shaped flow channel, and a minute gap between the discharge port and the suction port with respect to the passage path of the blade. A partition wall, a hub fixed to the rotating shaft, and a large number of blades that rotate integrally with the hub along the arcuate flow path. The circle connecting the ends is R1, the circle connecting the outer ends is R2, the circle connecting the centers of the inner and outer ends is Rc, and the circle connecting the centers of R1 and Rc is R.
When i, the value of R1 / R2 is smaller than 0.68, the pressure coefficient is 14 or more, and the position of the trailing edge of the blade on the circumference of Rc is larger than that of the inner end. The blade is delayed when viewed in the direction of rotation of the blade, and is delayed as it advances from the leading edge of the blade to the hub side, and the degree of the delay is increased from the inner end of the blade toward the outer end. Pumps characterized by being different.