JP7360264B2 - turbo fan - Google Patents

Description

The present invention relates to a turbofan.

Generally, in the process of manufacturing a machine having a fluid pump structure such as a fan, parts are joined together using various methods. For example, it has been disclosed that the cross-sectional shape of a welded portion formed on a blade in the transverse direction has a constant cross-sectional area in a direction away from the welded surface of the blade (see Patent Document 1). Further, a joint structure between the outer circumferential end of the blade and the shroud is disclosed (see Patent Document 2).

JP 2018-31329 Publication Patent No. 6415658

However, in order to obtain high performance in a turbo fan, a blade cover whose back surface is formed with a curved cross section in the direction of the rotation axis is required. Since such a blade cover has a curved shape on the side to be joined, it is not easy to join them with high strength using, for example, ultrasonic welding.

An object of the embodiments of the present invention is to provide a turbo fan in which a back blade cover including a curved surface having a curved cross section in the direction of the rotation axis is joined with high strength.

In the turbo fan according to the aspect of the present invention, the upper side of the blade is fixed, the back surface includes a curved surface whose cross section in the rotation axis direction is a curve, the upper surface of the outer peripheral end is flat, and the upper surface of the center side of the back surface is flat. A blade cover including a convex portion extending downward from the position, and a curved surface that is joined at the outer peripheral end of the blade cover and has a curved cross section in the direction of the rotation axis between the outer peripheral side and the inner peripheral side of the upper surface. a groove into which the lower side of the blade is fixed is formed in the curved surface, the back surface of the outer peripheral end is a plane parallel to the upper surface of the outer peripheral end of the blade cover; The present invention includes a blade under to which the convex portion of the cover passes and is fixed, and a motor for rotating a rotating body including the blade cover and the blade under.

According to an embodiment of the present invention, it is possible to provide a turbo fan in which a back blade cover including a curved surface having a curved cross section in the direction of the rotation axis is joined with high strength.

1 is a sectional view showing the configuration of a turbo fan according to an embodiment of the present invention. FIG. 2 is a perspective view of the structure of the blade cover according to the present embodiment, viewed from below. FIG. 2 is a perspective view of the structure of the blade under according to the present embodiment, viewed from above. FIG. 3 is a perspective cross-sectional view showing a joint portion between the blade cover and the blade under at the outer peripheral end according to the present embodiment. FIG. 3 is a perspective cross-sectional view showing a central joint between the blade cover and the blade under according to the present embodiment.

(Embodiment)
FIG. 1 is a sectional view showing the configuration of a turbo fan 20 according to an embodiment of the present invention. FIG. 2 is a perspective view of the structure of the blade cover 1 according to the present embodiment, viewed from below. FIG. 3 is a perspective view of the structure of the blade under 2 according to the present embodiment, viewed from above. Note that the same parts in the drawings are designated by the same reference numerals, and description thereof will be omitted as appropriate.

The turbo fan 20 includes a blade cover 1, a blade under 2, a sleeve 3, a magnet 4, a shaft 5, a core 6, a magnetic bearing 7, a substrate 8, a plate 9, an inner case 10, and an outer case 11.

The blade cover 1, the blade under 2, the sleeve 3, and the magnet 4 are components that constitute a rotating body. The sleeve 3, magnet 4, shaft 5, core 6, magnetic bearing 7, and substrate 8 are components that constitute an inner rotor type motor that serves as a power source for rotating a rotating body.

A shaft 5 is inserted into the cylindrical sleeve 3. The air dynamic pressure between the sleeve 3 and the shaft 5 constitutes an air dynamic pressure bearing that maintains the radial direction of the rotating body. An inner magnet 72 is provided on the outer peripheral side of the upper end of the shaft 5. An outer magnet 71 is provided on the inner peripheral side of the upper end of the sleeve 3 so as to be located near the outer side of the inner magnet 72. The outer magnet 71 and the inner magnet 72 constitute a magnetic bearing 7 that maintains the axial direction of the rotating body. The bottom side of the blade cover 1 and the top side of the blade under 2 are joined. The blade under 2 is attached to the upper end of the sleeve 3.

A cylindrical magnet 4 having a height lower than that of the sleeve 3 is attached to the outer circumferential surface of the sleeve 3 near the center in the vertical direction. For example, a back yoke is provided between the sleeve 3 and the magnet 4, and a magnet cover is placed on the outer circumferential side of the magnet 4 to prevent the magnet 4 from being destroyed by centrifugal force. The core 6 is arranged so as to cover the outer periphery of the magnet 4. For example, core insulators having insulation properties are provided on the upper surface side and the lower surface side of the core 6. The core 6 is wound in a coil together with a core insulator.

The substrate 8 is arranged on the outer peripheral side of the sleeve 3 below the magnet 4. The substrate 8 has a disk shape with a hole provided in the center through which the sleeve 3 passes. A control circuit for driving the motor is mounted on the board 8.

The plate 9 is a plate-shaped component that covers the bottom surface of the turbo fan 20. The substrate 8 may be fixed to the plate 9, or a cushion such as a contact sheet may be provided below the sleeve 3 to prevent the rotating body from directly contacting the plate during transportation. good.

The inner case 10 has a shape that completely covers the outer periphery of a portion of the motor located below the turbo fan 20. Inner case 10 is joined to plate 9 on the bottom side. For example, the core 6 and the substrate 8 are fixed to the inner case 10.

The outer case 11 is joined to the upper surface of the flange portion of the inner case 10 that protrudes toward the outer circumference so as to completely cover the blade cover 1 and the blade under 2. A resin such as rubber (for example, a modified O-ring) may be provided between the outer case 11 and the inner case 10 to improve the airtightness of the joint. The outer case 11 is provided with an intake port IN for taking in outside air and an exhaust port EX for exhausting outside air. The intake port IN is provided at the center of the upper surface of the outer case 11 so as to take in air from above in the vertical direction (rotation axis direction). The exhaust port EX is provided at one location on the side surface of the outer case 11 so as to exhaust air in the circumferential direction (direction perpendicular to the rotational axis).

As the blade cover 1 and the blade under 2 rotate, air is taken in from the intake port IN. The air taken in passes between the blade cover 1 and the blade under 2, flows into the space formed between the outer periphery of the blade cover 1 and the blade under 2, and the outer case 11, and is exhausted from the exhaust port EX. Ru.

The blade cover 1 has a shape in which a plurality of blades 21 and 22 are integrally formed on the back surface of a cover-shaped member. Note that, as long as the blades 21 and 22 are fixed to the blade cover 1, they may be separate members instead of being formed integrally with the blade cover 1. The blade cover 1 has a circular shape with a circular hole H1 provided in the center when viewed from the top or back side. The blade cover 1 has a plate shape as a whole, except for the blades 21 and 22, and has a curved shape like a base where the slope gradually becomes steeper from the outer circumferential side to the inner circumferential center. Therefore, the cross sections of the top and back surfaces of the blade cover 1 in the rotation axis direction are curved. As a result, the space formed below the blade cover 1 has a shape that gradually increases from the outer peripheral end to the center. The top and back surfaces of the outer peripheral end of the blade cover 1 are planes parallel to the ground. For example, the blade cover 1 is made of resin.

The upper sides of the blades 21 and 22 are fixed by being integrally formed as the blade cover 1. The lower sides of the blades 21 and 22 are fixed to the blade under 2. The blades 21 and 22 have a shape extending substantially in the radial direction so as to draw a gentle spiral curve. The first blade 21 has a longer shape than the second blade 22 in the longitudinal direction. The blades 21 and 22 are arranged side by side in the circumferential direction at regular intervals so that air can pass between the two adjacent blades 21 and 22. Specifically, the second blade 22 is arranged closer to the outer periphery between two adjacent first blades 21 . An outer circumferential convex portion C1 and an inner circumferential convex portion C2 are provided on the lower sides of both ends of the first blade 21 in the longitudinal direction. An outer circumferential convex portion C1 is provided below the outer circumferential end of the second blade 22 in the longitudinal direction. The outer peripheral convex portion C1 is located at the outer peripheral end of the blade cover 1. The inner circumferential convex portion C2 is located at the center of the blade cover 1, and specifically, is located below near the outer periphery of the hole H1 located at the center.

Note that each blade 21, 22 may have any shape as long as it can ensure air flow. Moreover, any blade may be provided with the outer circumferential side convex part C1 or the inner circumferential side convex part C2, or there may be a blade that is not provided with either the outer circumferential side convex part C1 or the inner circumferential side convex part C2. .

In addition, although the outer circumferential convex portion C1 and the inner circumferential convex portion C2 are described here as being provided on the blades 21 and 22, they may not be provided on the blades 21 and 22 if they are in the same position on the blade cover 1. It's okay. The outer circumferential convex portion C1 may be provided anywhere as long as it is an outer circumferential end located on the back side of a portion whose upper surface is flat. Further, the inner circumferential convex portion C2 may be provided anywhere as long as it is located inside (center side) of half the length from the outer circumference of the hole H1 of the blade cover 1 to the end of the blade cover 1. .

The blade under 2 has a circular shape with a circular hole H2 provided in the center when viewed from the top or back side. The upper surface of the blade under 2 has a generally curved shape like a skirt whose slope gradually becomes steeper from the outer circumferential side to the inner circumferential center. Therefore, the cross section of the upper surface of the blade under 2 in the direction of the rotation axis is a curve. The top and back surfaces of the outer peripheral end of the blade under 2 are planes parallel to the ground. For example, the blade under 2 is made of resin.

Note that the upper surface of the outer peripheral end of the blade cover 1 and the back surface of the outer peripheral end of the blade under 2 are both preferably parallel to the ground, but they do not need to be parallel to the ground as long as they are parallel to each other. . Furthermore, it is desirable that both the back surface of the outer peripheral end of the blade cover 1 and the upper surface of the outer peripheral end of the blade under 2 be parallel to the ground, but they may have any shape.

A plurality of grooves 23 and 24 are provided on the upper surface of the blade under 2. The first groove 23 is provided corresponding to the first blade 21 . The second groove 24 is provided corresponding to the second blade 22. The grooves 23 and 24 have shapes into which the lower portions of the blades 21 and 22 fit when the blade cover 1 and the blade under 2 are joined. By providing the grooves 23 and 24, the lower sides of the blades 21 and 22 are fixed to the blade under 2.

A hole D2 is provided at the inner circumferential end of the first groove 23, through which the inner circumferential convex portion C2 penetrates to the back side of the blade under 2. A concave portion D1 having a shape into which each of the outer convex portions C1 fits is provided at an end extending toward the outer circumferential side along each groove 23, 24. Note that the recess D1 may be provided anywhere as long as it corresponds to the outer circumferential convex portion C1 and is located on the upper surface of the portion whose back surface is flat. Further, the hole D2 may be provided anywhere as long as it corresponds to the inner peripheral convex portion C2.

FIG. 4 is a perspective cross-sectional view showing a joint portion between the blade cover 1 and the blade under 2 at the outer circumferential end according to the present embodiment.

The upper surface of the outer peripheral end of the blade cover 1 and the back surface of the outer peripheral end of the blade under 2 have a planar shape that is parallel to each other. This makes it easy to apply pressure from above and below to fix the outer circumference side ends in a state where the blade cover 1 and the blade under 2 are stacked vertically. In this state, by ultrasonically welding the outer circumference side ends, the outer circumference side convex portion C1 provided on each blade 21, 22 of the blade cover 1 and each concave portion D1 provided on the blade under 2 are welded. . For example, the tip of the outer circumferential convex portion C1 may have a pointed triangular cross section so that it can be easily welded by ultrasonic welding. When ultrasonic welding is performed, traces of the outer circumferential convex portion C1 or concave portion D1 may remain, but the overall finish of the joined portion will be clean. Note that the outer circumferential end of the blade cover 1 and the outer circumferential end of the blade under 2 may be joined in any manner other than ultrasonic welding.

FIG. 5 is a perspective cross-sectional view showing a central joint between the blade cover 1 and the blade under 2 according to this embodiment.

When the blade cover 1 and the blade under 2 are stacked vertically, the inner circumferential convex portion C2 provided on each first blade 21 of the blade cover 1 passes through the hole D2 of the blade under 2. In this state, the inner circumferential convex portion C2 is fixed so that it does not come out of the hole D2. For example, with the inner circumferential convex portion C2 protruding from the hole D2, the gap between the hole D2 and the inner circumferential convex portion C2 is fixed by filling the gap between the hole D2 and the inner circumferential convex portion C2 with an adhesive or the like from the back side of the blade under 2. This fixing is preferably performed after the outer circumferential end of the blade cover 1 and the outer circumferential end of the blade under 2 are joined, but it may be done first.

According to this embodiment, between the back surface of the blade cover 1 that includes a curved surface whose cross section in the rotation axis direction is a curve, and the upper surface of the blade under 2 that includes a curved surface whose cross section in the rotation axis direction is a curve, the blade In the turbo fan 20 in which a space including 21 and 22 through which air flows is formed, the blade cover 1 and the blade under 2 can be easily joined with high strength.

By forming the top and bottom surfaces of the space containing the blades 21 and 22 with curved surfaces as described above, the degree of freedom in the size and shape of the space can be increased. Thereby, a design that easily reflects the fluid flow, the specifications of the turbo fan 20, etc. can be made.

On the other hand, since the back surface of the blade cover 1 and the upper surface of the blade under 2 are formed with such curved surfaces, the blade cover 1 and the blade under 2 are joined with these curved surfaces facing each other. Generally, when joining (for example, welding) curved surfaces to each other, it is difficult to maintain the curved surfaces together before joining, making it difficult to perform the joining. On the other hand, in this embodiment, reliable joining can be easily performed in the following manner.

By making the upper surface of the outer circumferential end of the blade cover 1 and the back surface of the outer circumferential end of the blade under 2 parallel to each other, the outer circumferential end of the blade cover 1 and the back surface of the blade under 2 can be easily connected to each other before joining. It becomes easier to fix the outer peripheral side ends of the two in a state where they are overlapped. For example, by applying pressure to sandwich the overlapped blade cover 1 and blade under 2 from above and below, since the surfaces to which pressure is applied are flat, they can be easily fixed in this state. Thereby, these outer peripheral side ends can be stably joined by, for example, ultrasonic welding.

Further, by providing the inner circumferential convex portion C2 protruding from the back side of the blade under 2 on the center side of the blade cover 1, the blade cover 1 and the blade under 2 can be reliably joined at the center side.

Furthermore, by joining the blade cover 1 and the blade under 2 at the outer peripheral end and the center, the overall joint strength between the blade cover 1 and the blade under 2 can be increased.

Note that the present invention is not limited to the embodiments described above, and constituent elements may be deleted, added, or changed. Furthermore, a new embodiment may be created by combining or exchanging components of a plurality of embodiments. Even if such embodiments are directly different from the embodiments described above, those having the same meaning as the present invention are treated as embodiments of the present invention, and the explanation thereof will be omitted.

DESCRIPTION OF SYMBOLS 1...Blade cover, 2...Blade under, 3...Sleeve, 4...Magnet, 5...Shaft, 6...Core, 7...Magnetic bearing, 8...Substrate, 9...Plate, 10...Inner case, 11...Outer case, 20 ...turbo fan, 71...out magnet, 72...inner magnet.

Claims (5)

A blade whose upper side is fixed, whose back surface includes a curved surface with a curved cross section in the rotational axis direction, whose outer peripheral end has a flat upper surface, and which includes a convex portion extending downward from a central position on the back surface. cover and
The blade cover is joined at the outer circumferential end , and includes a curved surface having a curved cross section in the direction of the rotation axis between the outer circumferential side and the inner circumferential side of the upper surface, and is fixed so that the lower side of the blade fits therein. A blade under, in which a groove is formed in the curved surface, a back surface of the outer peripheral end is a plane parallel to the upper surface of the outer peripheral end of the blade cover, and the convex part of the blade cover penetrates and is fixed. and,
A turbo fan comprising: a motor for rotating a rotating body including the blade cover and the blade under. The turbo fan according to claim 1, wherein the blade cover is integrally formed with the blade. The turbo fan according to claim 2, wherein the convex portion is provided on the blade. A blade whose upper side is fixed, whose back surface includes a curved surface with a curved cross section in the rotational axis direction, whose outer peripheral end has a flat upper surface, and which includes a convex portion extending downward from a central position on the back surface. The cover includes a curved surface whose cross section in the direction of the rotation axis is a curve between the outer circumferential side and the inner circumferential side of the upper surface, a groove into which the lower side of the blade is fixed is formed in the curved surface, and the outer circumferential side A turbo fan comprising: a blade under whose end back surface is a plane parallel to the upper surface of the outer peripheral end of the blade cover; and a motor for rotating a rotating body including the blade cover and the blade under. A manufacturing method,
joining the outer peripheral end of the blade cover and the outer peripheral end of the blade under;
A method for manufacturing a turbo fan, comprising: penetrating and fixing the convex portion of the blade cover to the blade under. 5. The method of manufacturing a turbofan according to claim 4 , wherein the joining is performed by ultrasonic welding.

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