JPS6135396B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a multi-blade fan used in room air conditioners and the like.

[Prior art]

A conventional method for manufacturing a multi-blade fan will be explained with reference to FIGS. 1 to 5.

Reference numeral 1 denotes an elongated wing piece formed in an arc shape, and protrusions 1a and 1b are formed at both ends thereof. Reference numeral 2 denotes a disc constituting both ends of the multi-blade fan, in which slightly larger holes 2a having substantially the same shape as the wing protrusions 1a and 1b are bored at equal intervals along the circumference. Reference numeral 3 denotes a disc attached to the middle of the multi-blade fan, on which locking grooves 3a, which are approximately the same shape as the blades 1 and slightly larger, are formed at equal intervals around the circumference.

Then, the disks 2 and 3 are arranged at a predetermined interval and the wing piece 1 is assembled.
After fitting the protrusion 1a into the groove 3a of the disc 3 and the hole 2a of the disc 2, bend the wing protrusion 1a as shown in FIG. The tip of the outer periphery of the wire is caulked to form a protrusion 3b as shown in FIG. 5, and this is pressed against a part of the outer surface of the wing piece 1.

〓〓〓〓〓
According to such a conventional method of manufacturing a multi-blade fan,
Since a specially shaped wing piece 1 having protrusions 1a at both ends is used, the yield and productivity are lower than when both ends are simply cut in a straight line. In addition, since two types of discs 2 and 3 are used and two operations are required: bending the wing protrusion 1a and caulking the disc 3,
Workability was extremely poor. Furthermore, it is difficult to make the blade protrusion 1a evenly adhere to the disk 2 during the bending operation, and the blade cannot be sufficiently fixed by pressing the protrusion 3b of the disk 3 alone. These causes generate noise such as rattling sounds and squeaks when the multi-blade fan is used.

[Purpose of the invention]

The present invention has been made in an attempt to eliminate such deficiencies. That is, the purpose is to improve the yield and workability of the wing pieces, improve the workability of fixing the disk and the wing pieces, ensure the fixation, and prevent the generation of noise.

[Summary of the invention]

In the present invention, an arcuate wing piece 4 with both ends 4a and 4b cut in a straight line is formed, and grooves 5a, which have approximately the same shape as the wing piece 4 and are slightly larger, are formed at equal intervals on the circumference.
A disk 5 having protrusions 5b at the outer peripheral tip of the inner contour line 5e is formed, and the wing pieces 4 are fitted into the grooves 5a of the disk 5 with the disks 5 arranged at predetermined intervals. After that, both sides of the triangular portion 5d outside the outer contour line 5f of the groove 5a of the disk 5 are pressed to crush this triangular portion 5d, and this crushed portion 5' is widened on the outer surface of the wing piece 4. The blade 4 and the disc 5 are fixed by pressing at the surface and pressing against the inner surface of the blade 4 and the inner contour line 5e of the groove 5a.

The details of the present invention will be explained below with reference to an embodiment shown in FIGS. 6 to 10. Reference numeral 4 denotes an elongated wing piece formed in the shape of an arc, with its opposite ends 4a and 4 as shown in Fig. 6.
b is cut in a straight line. Reference numeral 5 denotes a disc attached to both ends and the middle of the multi-blade fan, and as shown in FIG. 7, grooves 5a having substantially the same shape as the blades 4 and slightly larger are formed at equal intervals around the circumference. Disc 5 has groove 5
A protrusion 5b is formed at the tip of the outer periphery of the inner contour 5e of a, and a notch 5c is formed at the tip of the outer periphery of the outer contour 5f.

Then, with the disks 5 arranged at predetermined intervals as shown in FIG. 9, the blades 4 are inserted into the grooves 5a of the disks 5 as shown in FIG. 7. At this time, the wing piece 4 is
It is locked by. After that, the groove 5a of the disc 5
When both sides of the triangular portion 5d outside the outer contour line are pressed to crush this triangular portion 5d, it deforms as a crushed portion 5d', and this crushed portion 5d'
The wing piece 4 and the disk 5 are fixed by being pressed against the outer surface of the blade over a wide area.

According to this method of manufacturing a multi-blade fan, the disc 5
Since the wing pieces 4 in which both ends of the wing pieces are cut in a straight line are used, the yield and productivity are improved compared to the conventional example. Also, disk 5
Since only one type is required, and only one type of work is required for fixing the blade 4 and the disk 5, work efficiency is improved. Furthermore, both sides of the triangular portion 5d outside the outer contour line of the groove 5a of the disk 5 are pressed and crushed, and the crushed portion 5d' of the moved material is pressed against the outer surface of the wing piece 4 over a wide area. Since the inner surface of the blade 4 is pressed against the inner contour line 5e of the groove 5a where the crushed portion 5d' is not provided, the crushed portion 5' can be pressed uniformly against the outer surface of the blade 4 with a strong force, and The pressure contact force does not weaken due to spring back action, and the disc 5 and the wing piece 4 can be fixed reliably and accurately. In addition, a protrusion 5b is formed at the outer peripheral tip of the inner contour line 5e of the groove 5a of the disc 5, and when crushing the crushing portion 5d', the protrusion 5b moves toward the blade 4 side as shown by arrow B. can be pressed into the groove, and the wing piece 4 can be reliably fixed at an accurate position from the center of the disk. Therefore, when using a multi-blade fan, vibration noise and
Noises such as squeaks can be prevented. In addition, even when used for a long time, play is less likely to occur between the wing pieces 4 and the disc 5.

According to this embodiment, since the notch 5c is formed at the tip of the outer contour line 5f of the groove 5a of the disk 5, the burr at the tip due to crushing can be reduced.

〔Effect of the invention〕

According to the present invention, since the end shape of the blade can be made simple, the yield and productivity of the blade 4 can be improved. Furthermore, by crushing, the blade 4 is brought into surface contact with the disk 5, and the position of the blade 4 is stably fixed by the protrusion 5d of the disk 5, so that the disk 5 and the blade 4 are fixed. Workability is improved, and the disk 5 can be securely and precisely fixed to the blade 4, preventing noise such as rattling and squeaks when the fan is used for a long time.
It can also withstand use.

[Brief explanation of the drawing]

Figs. 1 to 5 are explanatory diagrams of each process of a conventional multi-blade fan, Figs. 6 to 9 are explanatory diagrams of each process of the multi-blade fan of the present invention, and Fig. 10 is a cross section taken along line AA in Fig. 9. It is a diagram. 4... Wing piece, 5... Disc, 5a... Groove, 5b... Protrusion,
5c...notch, 5d...triangular part. 〓〓〓〓〓

Claims (1)

[Claims] 1. An arc-shaped wing piece with both ends cut into straight lines,
It consists of a disc forming an arc-shaped groove into which one end of the wing pieces is inserted at equal intervals on the circumference, and this disc has a protrusion on the outer peripheral tip of the inner contour line of the groove and an outer contour line 5.
A notch 5c is provided at the tip of the outer periphery of the disc 5, and a triangular crushed portion is provided between the outer circumference and the outer contour line of the disk 5, and a wing piece is provided at the outer contour line of the groove opposite to the crushed portion. A multi-wing fan characterized in that the wings are in line contact.