阅读说明：本技术 叶轮 (Impeller ) 是由 吉野慎吾 于 2019-07-09 设计创作，主要内容包括：本发明提供叶轮,其绕上下延伸的中心轴旋转,该叶轮具有：沿周向排列的多个叶片；沿径向扩展,且连接于上述多个叶片的下端的基底部；以及连结上述多个叶片的上部的支撑框架,上述叶片具有：相对于上述中心轴平行地上下延伸的叶片上部；以及位于比上述叶片上部靠下方,且相对于上述中心轴在周向上以预定的倾斜角倾斜地上下延伸的叶片下部。上述叶片上部的径向外端与上述支撑框架连接。(The present invention provides an impeller that rotates around a central axis extending vertically, the impeller including: a plurality of blades arranged in a circumferential direction; a base portion extending in a radial direction and connected to lower ends of the plurality of blades; and a support frame connecting upper portions of the plurality of blades, the blades including: a blade upper portion extending vertically in parallel with the central axis; and a blade lower portion located below the blade upper portion and extending upward and downward at a predetermined inclination angle in a circumferential direction with respect to the central axis. The radially outer end of the upper portion of the blade is connected to the support frame.)

1. An impeller which rotates around a central axis extending vertically,

comprising:

a plurality of blades arranged in a circumferential direction;

a base portion extending in a radial direction and connected to lower ends of the plurality of blades; and

a support frame connecting the upper parts of the blades,

the blade has:

a blade upper portion extending vertically in parallel with the central axis; and

a blade lower portion which is located below the blade upper portion and extends upward and downward at a predetermined inclination angle in a circumferential direction with respect to the central axis,

the radially outer end of the upper portion of the blade is connected to the support frame.

2. The impeller according to claim 1,

the angle of inclination of the blade lower portion increases as the blade extends radially outward.

3. The impeller according to claim 1 or 2,

the blade has:

a first curvature section disposed radially inward and curved in a plane perpendicular to the axial direction; and

a second curvature section which is arranged radially outward of the first curvature section and is curved in a plane perpendicular to the axial direction,

a center of a radius of curvature of the first curvature portion is disposed on a rotationally front side of the blade with respect to the first curvature portion,

the center of the radius of curvature of the second curvature portion is disposed on the rear side in the rotational direction of the blade with respect to the second curvature portion.

4. The impeller according to claim 1,

the upper surface of the base portion and the lower end of the lower portion of the blade are connected by a curved portion that curves in a plane perpendicular to the radial direction.

5. The impeller according to any one of claims 1 to 4,

the base portion has a boss portion disposed around the center axis and protruding upward,

the upper end of the hub portion is disposed below the lower end of the upper portion of the blade.

6. The impeller according to claim 5,

the radial inner ends of the blades are connected to the hub portion.

7. The impeller according to any one of claims 1 to 6,

the axial length of the upper part of the blade is more than the axial length of the support frame.

8. The impeller according to any one of claims 1 to 7,

the support frame is annular.

9. The impeller according to any one of claims 1 to 8,

the radially outer surface of the support frame extends radially inward as it faces downward.

Technical Field

The present invention relates to impellers.

Background

A conventional impeller (impeller) is disclosed in patent document 1. The impeller disclosed in patent document 1 includes a shaft, a plurality of blades arranged around the shaft and having a three-dimensional shape, and a hub portion. The hub portion is disposed around the shaft and protrudes from one end side toward the other end side in the axial direction. The impeller is formed by combining a blade portion having a shaft and a plurality of blades and a hub portion. Thus, an impeller having a plurality of blades with a three-dimensional shape can be manufactured by a simple manufacturing method without requiring a special device.

Disclosure of Invention

Problems to be solved by the invention

The blades of the conventional impeller disclosed in patent document 1 are connected to the hub portion at one end side where the hub portion is arranged in the axial direction. However, the blades of the impeller are not supported on the other end side in the axial direction, and thus have a problem of low strength. Further, the conventional impeller has a problem that it cannot rotate at a high speed and has a low air volume because of its low strength.

In view of the above, an object of the present invention is to provide an impeller capable of increasing the strength of blades and increasing the air volume.

Means for solving the problems

An exemplary impeller of the present invention rotates about a central axis extending up and down, and has: a plurality of blades arranged in a circumferential direction; a base portion extending in a radial direction and connected to lower ends of the plurality of blades; and a support frame connecting upper portions of the plurality of blades. The blade has: a blade upper portion extending vertically in parallel with the central axis; and a blade lower portion located below the blade upper portion and extending upward and downward at a predetermined inclination angle in a circumferential direction with respect to the central axis. The radially outer end of the upper portion of the blade is connected to the support frame.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the impeller provided by the invention, the strength of the blades can be improved, and the air volume can be increased.

Drawings

Fig. 1 is an overall perspective view of an example of an impeller according to an embodiment of the present invention.

Fig. 2 is a plan view of the impeller.

Fig. 3 is a side view of the impeller.

Fig. 4 is a longitudinal sectional view of the impeller.

Fig. 5 is a partial longitudinal sectional view showing the periphery of the support frame of the impeller.

Fig. 6 is a partial vertical cross-sectional view showing the periphery of the support frame of the impeller according to modification 1.

Fig. 7 is a partial side view of an impeller according to modification 2.

In the figure:

1-impeller, 11-impeller suction portion, 20-blade, 20 a-boundary portion, 21-blade upper portion, 22-blade lower portion, 23-first curvature portion, 23C-center of curvature radius, 24-second curvature portion, 24C-center of curvature radius, 25-connection portion, 30-base portion, 31-hub portion, 40-support frame, 40 a-radial outer surface, 202-blade, 212-blade upper portion, 222-blade lower portion, 302-base portion, 401-support frame, 401 a-radial outer surface, 502-bend portion, C-center axis, R-rotation direction, α -inclination angle.

Detailed Description

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present specification, a direction in which the center axis of the impeller extends is simply referred to as "axial direction", a direction perpendicular to the center axis with the center axis of the impeller as a center is simply referred to as "radial direction", and a direction along an arc with the center axis of the impeller as a center is simply referred to as "circumferential direction". In the present specification, for convenience of explanation, the shape and positional relationship of the respective portions will be described with the axial direction being the vertical direction and the vertical direction in fig. 1 and 3 being the vertical direction of the impeller. In the present embodiment, the "upper side" of the impeller shown in fig. 1 and 3 is the "suction side". The vertical direction is not defined to limit the orientation and positional relationship of the impeller during use. In the present specification, a cross section parallel to the axial direction is referred to as a "longitudinal cross section". The terms "perpendicular" and "parallel" used in the present specification do not mean perpendicular or parallel in a strict sense, and include substantially perpendicular and substantially parallel.

< 1. general structure of impeller

Fig. 1 is an overall perspective view of an example of an impeller 1 according to an embodiment of the present invention. Fig. 2 is a plan view of the impeller 1. Fig. 3 is a side view of the impeller 1. Fig. 4 is a longitudinal sectional view of the impeller 1.

The impeller 1 is circular with a center axis C as a center when viewed in the axial direction. The impeller 1 rotates about a central axis C extending vertically. As shown in fig. 1 and 2 as the rotation direction R, when the impeller 1 is viewed from above, the impeller 1 rotates clockwise. The impeller 1 includes a plurality of blades 20, a base portion 30, and a support frame 40.

The plurality of blades 20 are disposed above the base portion 30. The lower ends of the plurality of blades 20 are connected to the upper surface of the base portion 30. The plurality of blades 20 are arranged in the circumferential direction. The blades 20 extend in a direction separating radially outward from the center axis C, and extend axially upward and downward. The radially outer end of the vane 20 is disposed at the radially outer end of the base portion 30. The radially inner end of the vane 20 is disposed radially inward of the radially outer end of the base portion 30. The blades 20 are curved forward in the rotation direction R or rearward in the rotation direction R as they are spaced radially outward from the center axis C.

The base portion 30 is a lower portion of the impeller 1 and is disposed below the blades 20. The base portion 30 is connected to the lower ends of the plurality of blades 20. The base portion 30 is a disk-shaped member extending in the radial direction with respect to the center axis C. That is, the base portion 30 is expanded in the radial direction and connected to the lower ends of the plurality of blades 20. The base portion 30 supports the lower ends of the plurality of blades 20.

The support frame 40 is disposed above the impeller 1. The support frame 40 is a radially outer end of the impeller 1 and is disposed radially outward of the plurality of blades 20. The support frame 40 connects upper portions of the plurality of blades 20. Radially inward of the support frame 40 is an impeller air intake portion 11 of the impeller 1.

< 2. detailed structure of impeller

< 2-1. detailed Structure of blade >

Each of the plurality of blades 20 has a blade upper portion 21 and a blade lower portion 22. The blade upper portion 21 and the blade lower portion 22 are connected at a boundary portion 20a as a boundary line therebetween.

The vane upper portion 21 is disposed axially above the vane 20. The lower end of the blade upper portion 21 is connected to the upper end of the blade lower portion 22 at the boundary portion 20 a. The blade upper portion 21 extends vertically in parallel with the central axis C. The axial length of each blade upper portion 21 is the same in a direction separating radially outward from the center axis C.

The blade lower portion 22 is disposed axially below the blade 20. The upper end of the blade lower portion 22 is connected to the lower end of the blade upper portion 21 at the boundary portion 20 a. The lower end of the lower blade portion 22 is connected to the upper surface of the base portion 30. The blade lower portion 22 extends obliquely in the circumferential direction with respect to the center axis C. That is, the blade lower portion 22 is located below the blade upper portion 21, and extends vertically at a predetermined inclination angle α in the circumferential direction with respect to the central axis C. The pitch angle α represents the magnitude of the pitch of the blade lower portion 22 with respect to the central axis C.

The support frame 40 is disposed at the upper end of the impeller 1. The support frame 40 is disposed radially outward of the radially outer end of the blade upper portion 21. The radially outer end of the blade upper portion 21 is connected to a support frame 40. That is, the radially outer ends of the plurality of blade upper portions 21 arranged in the circumferential direction are connected in an annular shape by one support frame 40. Further, the support frame 40 may be disposed radially inward of the radially outer end of the blade upper portion 21.

According to the configuration of the above embodiment, the blade upper portion 21 is disposed on the upper side in the axial direction of the blade 20, so that the mold can be released upward in the axial direction when the mold is used. When the blade lower portion 22 is molded by a metal mold, the mold can be released outward in the radial direction. Therefore, the impeller 1 having the plurality of blades 20 in the three-dimensional shape can be easily molded.

Each of the plurality of blades 20 is configured to be bent toward the opposite side in the rotation direction R so that the blade upper portion 21 is parallel to the axial direction, with the boundary portion 20a as a boundary line. Therefore, the force applied during molding can be dispersed, and the strength of the plurality of blades 20 can be improved.

According to the structure of the above embodiment, the radially outer end of the blade upper portion 21 of each of the plurality of blades 20 is connected by the support frame 40, so that the radially outer end of the blade upper portion 21 parallel to the axial direction and the support frame 40 are fixed to each other. Therefore, the blade 20 is sandwiched and fixed between the support frame 40 and the base portion 30, and the strength can be improved. This enables the impeller 1 to rotate at high speed, and the air volume can be increased. Further, when the impeller 1 is molded by a metal mold, the blade upper portion 21 and the support frame 40 can be easily molded by being released upward in the axial direction.

The magnitude of the pitch angle α in the radially outer region of the blade lower portion 22 is different from the magnitude of the pitch angle α in the radially inner region of the blade lower portion 22. Specifically, a radially outer region of the blade lower 22 is inclined more largely with respect to the central axis C than a radially inner region of the blade lower 22. That is, the inclination angle α of the radially outer region of the blade lower portion 22 is larger than the inclination angle α of the radially inner region of the blade lower portion 22. The pitch angle α of the blade lower portion 22 changes continuously and smoothly as it goes away from the center axis C in the radially outward direction. Here, the rotational speed of the blades 20 increases as the blades extend radially outward of the impeller 1, and thus the wind resistance increases. At this time, the inclination angle α of the blade lower portion 22 shown in fig. 3 increases toward the radially outer side, so that the resistance of the wind radially outward of the impeller 1 can be reduced, and the efficiency of the impeller 1 can be improved.

As shown in fig. 2, the blade 20 has a first curvature 23 and a second curvature 24. The first curvature section 23 and the second curvature section 24 are continuously arranged in a direction away from the center axis C in the radial direction.

The first curvature section 23 is disposed radially inward, and is curved in a plane perpendicular to the axial direction. That is, the first curvature section 23 is disposed radially inward of the second curvature section 24. The radially inner end of the first curvature 23 is the radially inner end of the vane 20. The radially outer end of the first curvature 23 is connected to the radially inner end of the second curvature 24 via a connecting portion 25. The curvature radius center 23C of the first curvature section 23 is disposed on the front side in the rotation direction R of the blade 20 with respect to the first curvature section 23. The radius of curvature of the first curvature 23 is smaller than that of the second curvature 24.

The second curvature section 24 is disposed radially outward of the first curvature section 23, and is curved in a plane perpendicular to the axial direction. The radially outer end of the second curvature 24 is the radially outer end of the vane 20. The radially inner end of the second curvature 24 is connected to the radially outer end of the first curvature 23 via a connecting portion 25. The center 24C of the radius of curvature of the second curvature section 24 is disposed rearward of the second curvature section 24 in the rotational direction R of the blade 20. The radius of curvature of the second curvature portion 24 is larger than that of the first curvature portion 23.

According to the configuration of the above embodiment, since the vane 20 has the first curvature 23 configured as described above, the air sucked into the impeller 1 through the first curvature 23 can be made less likely to separate from the vane 20 in the vicinity of the impeller air intake portion 11. That is, the center 23C of the radius of curvature of the first curvature section 23 is disposed on the front side in the rotational direction R of the blade 20 with respect to the first curvature section 23, and the radially inner end of the blade 20 faces the front side in the rotational direction R. Further, the blades 20 have the second curvature portion 24 configured as described above, and thus air can be easily discharged from the inside of the impeller 1 to the radially outer side. That is, the center 24C of the radius of curvature of the second curvature section 24 is disposed on the rear side in the rotational direction R of the blade 20 with respect to the second curvature section 24, and the radially outer region of the blade 20 is directed to the opposite side to the front side in the rotational direction R. Therefore, the air volume characteristic of the impeller 1 can be improved.

< 2-2. detailed structure of base part >

The base portion 30 has a boss portion 31. The boss portion 31 is disposed around the center axis C of the base portion 30. The hub portion 31 is circular when viewed in the axial direction, with the center axis C as the center. The boss portion 31 protrudes upward with respect to the disc-shaped portion of the base portion 30. That is, the boss portion 31 is disposed around the center axis C and protrudes upward.

The hub portion 31 has a hub tubular portion 31a and a hub cover portion 31 b. The hub cylindrical portion 31a extends axially upward and downward along the center axis C. In the present embodiment, the hub tubular portion 31a is tapered. That is, the hub tubular portion 31a extends radially inward as it goes upward. The hub cover portion 31b is radially expanded at the upper end of the hub tubular portion 31 a. The hub cover portion 31b is circular when viewed in the axial direction, with the center axis C as the center. The radially outer end of the hub cover portion 31b is smoothly connected to the upper end of the hub tubular portion 31a via a curved surface. The lower end of the hub tubular portion 31a is smoothly connected to the upper surface of the base portion 30 via a curved surface. For example, in the present embodiment, a motor (not shown) for rotating the impeller 1 about the central axis C is disposed inside the hub portion 31.

The upper end of the boss portion 31 is disposed below the upper end of the blade 20. Specifically, the upper end of the boss portion 31 is disposed below the lower end of the blade upper portion 21. Since the base portion 30 has the boss portion 31, air can be smoothly guided from the impeller air intake portion 11 to the inside of the impeller 1. By disposing the upper end of the boss portion 31 below the lower end of the blade upper portion 21, the flow path of air near the impeller air intake portion 11 can be expanded. Therefore, the amount of air introduced into the impeller 1 can be increased.

The radially outer end of the hub portion 31 is disposed radially outward of the radially inner end of the blade 20. The radially inner ends of the blades 20 are arranged above the hub portion 31. The radially inner ends of the blades 20 are connected to the hub portion 31. According to this structure, the length of the blade 20 extending in the radial direction can be made as long as possible. Therefore, the air volume of the impeller 1 can be increased

< 2-3. detailed Structure of supporting frame >

Fig. 5 is a partial longitudinal sectional view showing the periphery of the support frame 40 of the impeller 1. In fig. 5, the right side is radially inward of the impeller 1, and the left side is radially outward of the impeller 1.

The radially outer end of the blade upper portion 21 is connected to the radially inner surface of the support frame 40. In the present embodiment, the upper surface of the blade upper portion 21 and the upper surface of the support frame 40 have the same height. The axial length L1 of the blade upper portion 21 is equal to or greater than the axial length L2 of the support frame 40. With this configuration, the blade upper portion 21 and the support frame 40 can be axially removed from the mold during molding. In addition, stability of the support frame 40 with respect to fixation can be improved.

As shown in fig. 2, the support frame 40 is an annular member centered on the central axis C when viewed in the axial direction. That is, the support frame 40 has a ring shape. With this configuration, generation of vortices that inhibit flow straightening can be suppressed near the support frame 40.

As shown in fig. 5, the radially outer surface 40a of the support frame 40 extends radially inward as it faces downward. Specifically, a lower portion of the radially outer surface 40a of the support frame 40 extends obliquely radially inward as it goes downward. Since the radially outer surface 40a of the support frame 40 extends radially inward as it goes downward, the air flow path under the support frame 40 is once narrowed in the axial direction radially outward, and then expanded in the axial direction. This can improve the rectification effect.

< 3. modification of impeller

< 3-1. modified example of impeller 1 >

Fig. 6 is a partial vertical cross-sectional view showing the periphery of the support frame 40 of the impeller 1 of modification 1. The impeller 1 of modification 1 has a support frame 401. The radially outer surface 401a of the support frame 401 extends radially inward as it faces downward. In detail, a lower portion of the radially outer surface 401a of the support frame 401 extends while being curved radially inward as it goes downward. The lower portion of the support frame 401 is downwardly convex. In comparison with the structure shown in fig. 5, the support frame 401 of modification 1 shown in fig. 6 is curved downward, so that the air flow path is once narrowed in the axial direction toward the radial outside, and then smoothly widened in the axial direction. This can improve the rectification effect.

< 3-2. modification example 2 of impeller

Fig. 7 is a partial side view of an impeller 1 according to modification 2. Impeller 1 of modification 2 includes a plurality of blades 202 and a base portion 302. The blade 202 has a lower blade portion 222.

The lower end of the lower portion 222 of the vane is attached to the upper surface of the base portion 302. The upper surface of the base portion 302 and the lower end of the blade lower portion 222 are connected by a bent portion 502 that is bent in a plane perpendicular to the radial direction. In the present embodiment, the bent portions 502 are disposed on the front side in the rotation direction R and the rear side in the rotation direction R of the lower end of the blade lower portion 222. With this configuration, the connection region between the base portion 302 and the blade lower portion 222 can be made smooth. This can improve the rectification effect.

< 4. other >)

While the embodiments of the present invention have been described above, the scope of the present invention is not limited to the embodiments, and various modifications can be made without departing from the scope of the present invention. The above embodiments and modifications thereof can be combined as appropriate.

Availability in production

The present invention can be used for an impeller, for example.