JPH094598A - Manufacture of impeller for centrifugal blower having aerofoil blade - Google Patents

Abstract

PURPOSE: To precisely and easily manufacture an impeller for a centrifugal blower having a hollow aerofoil blade. CONSTITUTION: A shroud 1 and blades F1 -F8 are integrated by the aluminum die casting. A recessed part 3 which is open to the lower end face is formed in the blades F1 -F8 . A preliminarily pressed main plate 11 is abutted on the lower end part of the blades F1 -F8 , and a rivet 15 is passed through the recessed part 3 to fix the shroud 1 to the main plate 11. Positioning of the blades and the three dimensional machining of an upper end part are unnecessary, and the recessed part 3 forms a hollow part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an impeller (fan runner) for a centrifugal blower in which the blade has a streamlined blade shape.

[0002]

2. Description of the Related Art A centrifugal blower is a blower having a structure in which an impeller having a plurality of fixed blades is rotated in a casing and air sucked in from the center of a rotating shaft is blown out in a radial direction. There are types such as a multi-blade blower, a turbo blower, and a wing blower depending on the form of the casing and the like, and among them, a so-called wing blower having a blade shape having a thickness and an aircraft wing shape is High efficiency and low noise.

Explaining in detail based on the conventional general airfoil blower 101 shown in FIG. 12, a fan runner 103 rotatably housed in a casing 102 is rotated by an appropriate rotary drive shaft 104, Air sucked from the suction port 105 formed in the axial direction is blown out from the discharge port 106 in the radial direction.

The fan runner 103 itself has a shroud 107 serving as a side plate on the suction port 105 side and a main plate 108.
And a plurality of blades 109 that are fixed between the shroud and the shroud so that the wind speed is almost the same at any distance from the center of rotation in order to increase the efficiency of the blower. At 107, there is usually a circumferential gradient. That is, the shroud 107 is formed in a substantially conical shape. In addition, each blade 109 has a streamlined shape having a thickness like an aircraft wing, as shown in FIG. Therefore,
The intersection (contact portion) between the shroud 107 and the blade 109 is
It has a three-dimensional curved surface.

When manufacturing such a fan runner 103, conventionally, the entire fan runner 103 is integrally manufactured by aluminum die casting or the like, or the blades 109 formed by three-dimensionally cutting an aluminum extrusion die material are shrouded one by one. It was fixed to 107 and the main plate 108 with screws or the like.

[0006]

However, in the method of integrally manufacturing the entire fan runner 103 by the above-mentioned aluminum die casting or the like, there is a problem that the inside of the blade 109 cannot be made hollow and the weight increases. In addition, the price was high because each product was manufactured. On the other hand, when the blades 109 are formed by three-dimensional cutting of an aluminum extruded die material, the inside of the blades can be hollow with an equal cross section so that the weight can be reduced, but each blade 109 is three-dimensionally cut. Therefore, it takes much time and labor, and the processing cost is high. Further, since it is the work of fixing the blades 109 to the shroud 107 and the main plate 108 one by one, it is difficult to perform positioning, and the accuracy and workability are not preferable either.

The present invention has been made in view of the above points, and it is easy to form the hollow portion of the blade and it is not necessary to position each blade. It is an object of the present invention to provide a method for manufacturing the above and solve the above problems.

[0008]

In order to achieve the above object, according to claim 1, a blade whose one end is located on the main plate and the other end is located on the side plate on the suction port side has a thick outer shape. A method for manufacturing an impeller for a centrifugal blower having a shape, in which a side plate and a blade are integrally molded by a method of injecting a molten material into a mold, and from one end side of this blade. A method for manufacturing an impeller for a centrifugal blower having an airfoil blade, characterized in that a concave portion is formed, and a preprocessed main plate and one end portion of the blade are joined and fixed.

According to a second aspect, one end portion of the main plate,
A method for manufacturing an impeller for a centrifugal blower, wherein the other end of the blade positioned on the side plate on the suction port side has a thick airfoil, which is closer to the other end of the side plate and the blade. The part is integrally molded by the method of pressure injection of the molten material into the mold,
The remaining portion of the blade is manufactured separately with a hollow structure, the other end side of the remaining portion of the blade is fitted to the portion near the other end, and the main plate preprocessed and the remaining portion of the blade A method for manufacturing an impeller for a centrifugal blower having airfoil blades, the method including joining and fixing one end side thereof.

In each of the above manufacturing methods, when fixing the main plate and one end of the blade, or the part of the main plate near the one end of the blade, as described in claim 3, the blade is provided between the main plate and the side plate. It may be fixed by a member penetrating the hollow part of the device, such as a screw, a rivet, or a through bolt.

As an example of the method for injecting the molten material into the mold in each of the above manufacturing methods, when the material is a metal,
A so-called die casting method can be used, and when a synthetic resin such as plastic is used as a material, an injection molding method can be used. In any case, each of these methods enables precise molding.

[0012]

According to the first aspect of the present invention, the side plate and the blade are integrally formed by the method of injecting the molten material into the mold. However, it is of course easy to form the recess from the one end side inside the blade. is there. Then, for example, when the main plate that has been pressed in advance and one end of the blade are joined and fixed, the recess becomes a hollow part as it is. Therefore, it is easy to form the hollow portion of the blade. Further, since the blade is formed integrally with the side plate, it is not necessary to position the blade.

In the manufacturing method according to the second aspect, not all the blades are integrally formed with the side plate as described above, but a part thereof, that is, a portion near the other end of the blade is integrally formed with the side plate. It is supposed to do. Then, since the remaining portion of the separately manufactured hollow blade is fitted to the portion near the other end, it is not necessary to position the blade. The rest of the hollow structure of the vanes can easily be manufactured, for example by extrusion. Finally, since the pre-processed main plate and the portion near the one end of the blade are joined and fixed, it is easy to form the hollow portion of the blade.

As described in claim 3, a member penetrating the hollow portion of the blade between the main plate and the side plate, such as a screw, a rivet, or a through bolt, is used to remove the blade from one end of the blade and the main plate or one end of the blade. By fixing the portion and the main plate, the fixing work is easy and the blades are firmly fixed to the main plate.

[0015]

EXAMPLE An example of the present invention will be described below with reference to the drawings. First, the shroud 1 shown in FIG. 1 is manufactured by aluminum die casting. FIG. 1 shows a plan view of the shroud 1, the outer shape of which is substantially frustoconical, and a circular suction port 2 is formed in the central portion.

Inside the shroud 1, eight blades F1 to F8 are integrally formed. Each of the blades F1 to F8 has the same shape and size, and the upper end portion thereof is integrated with the inner side surface of the shroud 1. The lower end of each blade F1 to F8 is shown in FIG.
As shown in, it is molded flat. Further, inside each of the blades F1 to F8, a recess 3 that opens to the lower end side is formed at the same time, and the ceiling wall of each recess 3 is formed by the inner side surface of the shroud 1.

Through holes 4, 5 are formed in the shroud 1 at positions corresponding to the recesses 3 of the blades F1 to F8, respectively, which penetrate into the recesses 3. The shroud 1 including the through holes 4 and 5 is integrally manufactured by aluminum die casting together with the blades F1 to F8.

Further, the main plate 11 shown in FIG. 3 is manufactured separately. FIG. 3 shows a plane of the main plate 11, and FIG.
As shown in FIG. 3, the central portion 11a is formed in a truncated cone shape so as to be convex upward, and the through hole 1 is formed at the center thereof.
A drive shaft fixing boss 12 having 2a is provided. The shroud 1 is provided on the flat portion of the main plate 11.
Through holes 13 and 14 corresponding to the through holes 4 and 5 formed in the above are respectively concentrically formed.

That is, as shown in FIG. 3, when the shroud 1 and the main plate 11 are combined facing each other and the lower end portions of the respective blades F1 to F8 are brought into contact with the upper surface of the main plate 11 (each blade F1 at that time). (The position of the lower end of F8 is indicated by a chain double-dashed line in FIG. 3), the through hole 13 is provided so as to face the through holes 4, 5 of the shroud 1,
14 so as to be located in the concave portion 3 of each of the blades F1 to F8,
The through holes 13 and 14 are formed. The drive shaft fixing boss 12 and the main plate 11 are integrally formed by press working.

Next, as shown in FIG. 5, the shroud 1 and the main plate 11 having the above-described structure are combined so as to face each other, and the lower ends of the blades F1 to F8 are brought into contact with the upper surface of the main plate 11. Then, the concave portion 3 of each of the blades F1 to F8 will have the chiodo main plate 11
The upper surface of the blade 3 is covered with a lid, and the recesses 3 form the hollow portions of the blades F1 to F8 as they are.

After that, as shown in FIG. 6, a fixing member penetrating between the through holes 4 and 5 formed in the shroud 1 and the through holes 13 and 14 of the main plate 11 corresponding to these through holes 4 and 5, respectively. , For example, using the rivet material 15 as shown in FIG.
The shroud 1 and the main plate 11 are fixed. That is, the rivet material 15 is put into the hollow portions of the blades F1 to F8 from the shroud 1 side, and the projecting end portion thereof is firmly caulked on the bottom surface of the main plate 11 side. As a result, the shroud 1 and the main plate 11 are firmly fixed to each other, and the rivet material 15 described above has the blades F
Since the shroud 1, the main plate 11, and the blades F1 to F8 are contained in the hollow portion 1 to F8, the integrity is extremely strong. Of course, instead of the rivet material 15 described above,
Through bolts or screws may be used.

As is clear from the above manufacturing process,
Compared with the conventional method of manufacturing the entire fan runner by aluminum die casting, the fan runner manufactured according to the present invention has a hollow portion formed inside each of the blades F1 to F8, and the weight is reduced as compared with the conventional method. There is.

Further, compared with the conventional method of mounting the blades manufactured by extrusion molding one by one, the positioning of the blades is not required, and the three-dimensional processing of the joint between the upper end of the blade and the inner surface of the shroud is also unnecessary. is there. Therefore, the work is extremely easy and the quality is improved.

Further, in the above embodiment, the fixing through holes 4 and 5 formed in the shroud 1 are the shroud 1 and each blade F1.
Since they are formed during the integral molding of F8 to F8, the accuracy of the position of forming the through holes is higher and the man-hours are reduced as compared with, for example, a method of punching a curved surface after pressing.

Since the lower ends of the blades F1 to F8 may be molded flat, for example, the vertical lengths of the blades F1 to F8 can be arbitrarily set, and fan runners having various blade heights can be set. Can be manufactured.

In the above embodiment, the shroud 1 and the blade F1
The entire process of ~ F8 was integrally molded, and then the main plate 11 was joined and fixed. However, instead of this, only a part of the blade was integrally molded with the shroud, and then the blade was formed on the part. The main plate may be finally joined and fixed after the rest of the above is attached.

FIGS. 7-11 show the process of such an alternative embodiment, wherein the shroud 21 shown in FIG. 7 has on its inner surface the upper ends UF1 to UF8 of the blades (however, for convenience of the drawings, the blades are not shown). The upper end portions UF4, UF5 and UF6 are omitted) and are integrally manufactured by aluminum die casting.

In the upper end portions UF1 to UF8 of the blades, there are formed recesses 22 that open downward, and the outer circumference of each recess 22 is slightly smaller than the upper end portion of the blade. A small protrusion 23 is formed. In addition, 24 is a suction port, and 25 is a through hole opened in each recess, and another through hole is formed on the outer periphery of this through hole 25 as in the above embodiment.

On the other hand, the remaining portion DF1 of the blade shown in FIGS.
~ DF8 (However, for convenience of drawing, the remaining blades DF4, DF
5 and DF6 are omitted) are manufactured by, for example, aluminum extrusion molding. Remaining part of each of these blades DF1 ~
The DF8 has the same shape and the same size, its upper and lower end faces are flat, and has a hollow portion 26 open to the upper and lower end faces therein. Therefore, the remaining portions DF1 to DF8 of these blades have a shape that can be easily extruded, and can be mass-produced at the same cost at a low cost by appropriately cutting the blades at a right angle at regular intervals.

Then, as shown in FIGS. 8 and 9, the projections 23 of the upper end portions UF1 to UF8 of the respective blades are replaced by the remaining portions DF of the respective blades.
1 to DF8 are fitted into the hollow portion, both are fitted to each other, and the upper ends UF1 to UF8 of each blade and the remaining portions DF1 to DF8 of each blade
Eight blades are formed by integrating and.

After that, as in the case of the above-described embodiment, as shown in FIG. 10, the upper surface of the main plate 11 is brought into contact with the lower end surfaces of the remaining portions DF1 to DF8 of the blades, and the shroud 21 and the main plate 1 are made.
1 and face each other and combine. Then, the concave portions 22 of the upper end portions UF1 to UF8 of the respective blades and the remaining portions DF1 to D of the respective blades.
With the hollow portion 26 of F8, the hollow portion of the blade is formed.

Next, as shown in FIG. 11, between the through hole 25 formed in the shroud 21 and the corresponding through holes 13 and 14 of the main plate 11, for example, the bolt 27 and the nut 2 are provided.
Tighten and fix with 8 to shroud 21 and the rest of each blade D
The F1 to DF8 and the main plate 11 may be integrally fixed.

In this embodiment, a part of the blade, that is, the upper end portions UF1 to UF8 of the blade and the shroud 21 are integrally molded,
Then, set the remaining parts DF1 to DF8 of each blade to the upper end UF of each blade.
1 to UF8 are fitted, and then the main plate 11 is fixed. Again, like the above-mentioned embodiment, the fan runner can be manufactured more easily and more accurately than before, and the hollow portion is formed inside the blade. It is possible to manufacture a lightweight fan runner in which the above is formed. Also, the remaining parts of each blade DF1 to DF8
It is also possible to manufacture fan runners having various blade heights by changing the vertical length of the fan runner.

[0034]

According to the invention described in claims 1 to 3, it is easy to manufacture an impeller having a blade having a hollow portion,
A lightweight impeller can be provided. Moreover, it is not necessary to position the vanes during manufacture. Claim 1
In this case, since the process of integrally forming all of the blades with the side plate and then fixing the main plate is adopted, the manufacturing work can be facilitated and the cost can be kept low. Claim 2
However, since a part of the blade and the side plate are integrally molded, the manufacturing is easy and the cost is correspondingly low. Claim 3
According to the invention, the fixing work is easy, and the blade is firmly fixed to the main plate.

[Brief description of drawings]

FIG. 1 is a plan view of a shroud used in an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a plan view of a main plate used in an example of the present invention.

FIG. 4 is a sectional view taken along line BB of FIG. 1;

5 is a longitudinal sectional view showing a state in which the shroud shown in FIG. 1 and the main plate shown in FIG. 3 are combined.

6 is a vertical cross-sectional view showing a state in which the shroud of FIG. 1 and the main plate of FIG. 3 are fixed to each other by using a rivet material.

FIG. 7 is a vertical cross-sectional view of a shroud according to another embodiment.

8 is a vertical cross-sectional view showing how the remaining portion of the blade is fitted into the shroud of FIG.

FIG. 9 is a perspective view showing how the upper end of the blade and the rest of the blade are fitted together.

10 is a vertical cross-sectional view showing a state in which the shroud shown in FIG. 7 and the main plate shown in FIG. 3 are combined.

11 is a vertical cross-sectional view showing a state in which the shroud of FIG. 7 and the main plate of FIG. 3 are fixed using bolts and nuts.

FIG. 12 is a vertical cross-sectional view of a shroud manufactured by a conventional method.

FIG. 13 is a plan view of a shroud manufactured by a conventional method.

[Explanation of symbols]

 1 Shroud 2 Suction Port 3 Recesses 4, 5 Through Hole 11 Main Plate 13, 14 Through Hole 15 Rivet Material F1 ~ F8 Blade

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomoyoshi Noda 4-4-13-903 Nagayama, Tama City, Tokyo

Claims (3)

[Claims] 1. A method for manufacturing an impeller for a centrifugal blower, wherein one end of a blade is located at a main plate and the other end is located at a side plate on the suction port side, and the outer shape of the blade has a thick blade shape. Then, the side plate and the blade are integrally molded by a method of injecting the molten material into the mold to form a recess from one end side of the blade,
A method for manufacturing an impeller for a centrifugal blower having airfoil-shaped blades, characterized in that a preprocessed main plate and one end portion of the blades are joined and fixed. 2. A method for manufacturing an impeller for a centrifugal blower, wherein one end of the blade is located on the main plate and the other end is located on the suction side plate, and the outer shape of the blade has a thick airfoil. Then, the side plate and the portion near the other end of the blade are integrally molded by a method of injecting the molten material into the mold to form the remaining portion of the blade into a hollow structure and separately manufactured. The airfoil blade is characterized in that the other end side of the blade is fitted to a portion near the other end, and a preprocessed main plate and one end side of the remaining portion of the blade are joined and fixed. A method for manufacturing an impeller for a centrifugal blower having the same. 3. The centrifugal blower having airfoil blades according to claim 1, wherein the fixing is performed by a member penetrating the hollow portion of the blade between the main plate and the side plate. Impeller manufacturing method.