JPS6018243A - Production of hollow vane - Google Patents

Abstract

PURPOSE:To eliminate the operation for providing reinforcing ribs to a vane after formation of a vane shell by forming the reinforcing ribs on a developed plate of the vane surface formed by pressing then bending the developed plate to a prescribed shape with the ribbing side positioned on the inside and welding the bent free ends to each other. CONSTITUTION:A metallic plate 8 is pressed by a press device D provided with an upper die d1 and a lower die d2 to form a developed plate 9 of the vane surface developed with the vane surface shape of a hollow vane 3 and to form a step part 9a corresponding to the front edge of a vane shape 4 and projecting parts 9b, 9c corresponding to reinforcing ribs 5. The plate is then pressed to sandwich the parts 9b, 9c by another press device and said parts are fixed by welding to form the ribs 5 in the state of projecting on the plate 9. The plate 9 with the ribs 5 positioned on the inside is thereafter bent to the shape of the vane shell 4 at the step part 9a and the bent free ends are joined by welding. The operation for providing the reinforcing ribs to the hollow vane is thus completed before the formation of the vane shell and the workability is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a method of manufacturing a hollow blade used for a rotor blade of a centrifugal blower.

<Prior Art> Conventionally, in order to reduce the weight of a centrifugal blower, the rotor blades were used as shown in Fig. 1, for example.
A hollow wing (c) is used, which consists of a hollow wing membrane (a) forming a wing surface of a predetermined shape, and a reinforcing member (1) inserted and fixed into the hollow wing membrane (a). Special public show b 2-4
7567 @Refer to publications, etc.) However, conventionally, when manufacturing this hollow R (C) from metal, the hollow blade membrane < a
> is formed into a predetermined hollow shape, the hollow blade membrane (a)
The conventional method was to insert a reinforcing member (b) into the reinforcing member and fix it by welding. Therefore, especially when the thickness of the hollow blade (C) is large (approximately 10 mm 1'a), welding of the reinforcing member (b) becomes difficult, resulting in a problem of poor workability.

In addition, the above-mentioned publication states that by covering the outer periphery of the hollow wing membrane (a) lI3 and the reinforcing member (b) with a synthetic resin, the characteristics of the synthetic resin (the tackiness of the uncured synthetic resin) are utilized. A method is disclosed in which the reinforcing member (b) is consolidated into the hollow blade membrane (a) without the need for welding. However, in hollow blades (c) whose hollow m-shells (a) etc. are made of synthetic resin, the surface of the hollow m-shells (a) is inevitably rougher than those made of metal, resulting in greater air resistance. There are problems such as this, and there are also drawbacks in terms of strength, making C1 impractical.

(Objective of the present invention) The object of the present invention is the previous)! In the manufacture of hollow blades such as IS, work efficiency is improved by attaching reinforcing members to the hollow membrane before forming the hollow membrane into a predetermined hollow shape, instead of after forming the hollow membrane into a predetermined hollow shape. It is.

(Structure of the Invention) To achieve the above-mentioned object, the structure of the present invention is to prepare a wing surface expansion plate formed in a shape in which the wing surface of a hollow wing is expanded by press working, and to After forming the reinforcing ribs on the side, bend the -C wing surface expansion plate in two so as to form a wing surface of a predetermined shape, with the reinforcing rib forming side facing inside, and fold the bent free ends of the wing surface expansion plates together. They are joined together by welding to form a hollow blade. As a result, reinforcing ribs can be provided in the hollow wing shell in advance without requiring welding and fixing of the reinforcing ribs to the hollow film after the bending and forming of the wing surface plate, that is, after the formation of the hollow wing shell. This is how it was done.

(Effects of the Invention) Therefore, according to the present invention, reinforcing ribs can be provided in advance in the hollow wing shell without requiring welding and fixing of the reinforcing ribs to the hollow membrane after the formation of the hollow wing shell. Therefore, the reinforcing ribs can effectively reinforce the hollow Schiff acid to increase the strength of the hollow blade, and at the same time, it is possible to improve the workability by making the work easier.

<Example> Hereinafter, an example as a specific example of the technical means of the present invention will be described with reference to the drawings.

Figures 2 and 3 show the rotor (A) of a centrifugal blower, and this rotor (A) is connected to the drive shaft of the drive motor (
A circular plate (2) is attached to the plate (2) via a mounting member (1), and a large number of rotor blades are installed on the side surface of the plate (2) at equal pitches in the circumferential direction. It is equipped with hollow blades (3), <3), .

Each of the hollow blades (3) is made of a hollow film (made of metal such as aluminum alloy) that forms the blade surface, as shown in detail in FIG.
4) Reinforcing ribs (4) for reinforcing the hollow membrane (4)
5) and (5).

In addition, the mounting base end and tip end of each hollow wing (3) are fitted into the fitting holes (6) and (6') provided in the plays 1 to (2) and the ring (7), respectively. Welded all around the outer surface (×
) is fixed.

Next, a method of manufacturing the hollow blade (3) as a first embodiment of the present invention will be explained with reference to FIG.

That is, when manufacturing the hollow blade (3), first, as shown in FIG. The plate (8) is pressed to form a wing plate (9).The wing plate (9) has a shape in which the trailing edge of the hollow space membrane (4) is separated and expanded, 110 of the hollow membrane (4) in the center of the path
The edge has a corresponding step (9a), and the step (9a)
A protrusion (with an inverted U-shaped cross section) is placed at a predetermined position on both sides of the
9b) and (9G).

Subsequently, each protrusion (9b), (
9c) in a press equipment different from the above-mentioned press equipment (I)
(not shown), and by welding and fixing the both side walls, the reinforcing ribs (5), (5) are projected on the four-sided expansion plate 9). (see FIG. 5(b)).

After that, the reinforcing ribs (5), (5) are formed on the inner side, and the four-sided expansion plate (9) is bent to form the hollow film (4) with the stepped portion (9a) as the center. Bend it in two, and open the bent free end (hollow film-forming (4) of the wing surface spreading plate (9)
) are joined to each other by welding (see Figure 5 (
See C).

As a result of the above, the reinforcing ribs (5), (
5) is formed.

The reinforcing ribs (5), (5) are meshed in the length direction of the hollow blade (3) within the hollow membrane (4), and the tips are formed with a predetermined gap on the inner surface of the hollow IM shell (4). The reinforcing ribs (5), (5) prevent the hollow inner shell (4) from deforming even when the hollow blade (3) thermally expands. I have to.

Therefore, according to the manufacturing method of the hollow wing (3), before the wing surface spreading plate (9) is bent to form the hollow inner shell (4), reinforcing ribs are added to the inner surface spreading plate (9). (5), (5
) can be formed in advance, and after molding the hollow inner shell (4), it is possible to form the hollow wing 3) having the reinforcing ribs (5), (5) inside the hollow wing M(4). Since it is not necessary to insert a reinforcing member into the hollow inner shell (4) and fix it by welding after molding the hollow inner shell (4) as in the conventional case, the hollow wing
Even when the thickness of the blade (3) is thin, the manufacturing operation of the hollow blade (3) can be easily performed.

Moreover, the reinforcing ribs (5), (5) are formed before forming the hollow N-shell (4), while the respective protrusions (9b
), (9c) is pressed on both sides with a scissor /υ,
Since it is simply fixed by welding, workability can be further improved.

Moreover, since the hollow inner shell (4) is effectively reinforced by the reinforcing ribs (5), (5) inside the hollow wing (3), the strength is increased. It is possible to improve sexual performance, etc.

6 and 7 are the second and third embodiments of the present invention, respectively.
This shows a method for manufacturing a hollow blade (3) as an example,
These manufacturing methods involve forming a hollow inner shell (4) by press working.
After welding reinforcing ribs (5'), (5') having a cross-sectional shape on the same plane plate (9') formed in the expanded shape of the wing plate (9'), ′) is bent and reinforcing ribs (5′) and (5′) are placed inside the hollow inner shell (4′).
A hollow R (3') is formed and covered.

Here, the reinforcing rift (5') inside the hollow inner shell (4')
, (5') are set so that they face each other inwardly in the second embodiment (see FIG. 6 (C-)), and in the third embodiment, they are set so that they face each other outwardly, that is, back to back. (See Figure 7(C)). Furthermore, it goes without saying that the same effects as in the first embodiment can also be achieved using these manufacturing methods.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a hollow blade as a conventional example, Figs. 2 to 7 show embodiments of the present invention, and Fig. 2 is a plan view showing a rotor of a centrifugal Igi machine. Figure 3 is a cross-sectional view of the same, Figure m4 is a cross-sectional view of the inside of the hollow, and Figures 5 to 7 show the WA manufacturing method of hollow blades as the first to third embodiments, respectively.J-Manufacturing process diagram It is. (3)...Hollow wing, (5), (5')...Reinforcement rib, (9), <9')...Wing surface extension plate. Start Figure 1 O Figure 2 Beat 4 Figure 3

Claims (1)

[Claims] (1) Pressing] A wing surface expansion plate (9) formed in a shape in which the wing surface of the hollow wing (3) is expanded is prepared, and reinforcing ribs (5) are attached to the wing surface expansion plate (9). . . . . After forming the reinforcing rib (5), . . . the wing surface extension space 4f; t (9) is folded into two with the forming side inward so as to form a wing surface of a predetermined shape. , the wing surface plate (9)
A method for manufacturing a hollow wing, characterized by joining the bent free ends of the two to each other by welding to form a hollow wing (3).