JPH0127280B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a guard for an electric fan, and particularly aims to provide a low-cost product and a low-cost manufacturing method through effective use of materials and rationalization of processes.

A conventional electric fan guard will be described below with reference to the drawings.

A first conventional example will be explained with reference to FIGS. 1, 2, and 3. 1 is a small ring, 2 is a large ring,
Reference numeral 3 designates a plurality of guard rods whose both ends are radially fixed to the small ring 1 and the large ring 2 by means such as welding, fitting, or caulking. (The figure shows a welded type) Two half guards are made by fixing multiple guard rods 3 radially to the small ring 1 and large ring 2, and the large ring 2 is joined to form the main guard, and the motor 4 is fixed around the bearing 5 of.
Note that the electric fan in FIG. 1 is omitted.
Further, 6 is a mark stand on which a mark with a registered trademark representing the manufacturer is usually attached.

However, in the conventional structure described above, the small ring 1, large ring 2, and guard rod 3 are each manufactured separately and assembled, so many steps are required for manufacturing.
In addition, there was a drawback that non-uniformity of the product was likely to occur due to assembly. A conventional example that improves this point of having a large number of parts is shown below. A second conventional example will be explained with reference to FIG. In this example, since the guard has the function of protecting the fan, the material is formed into an arm shape that encloses and protects a space slightly larger than the space of the fan, and is punched out using a press to form a space 7 through which airflow passes. Although the remaining portion is used as a guard rod 8, it is desirable that the space 7 through which the airflow passes is made as large as possible in consideration of air resistance. However, if the space 7 is made larger, the amount of scrap increases and the material yield deteriorates, and the guard rod portion 8 cannot be made too thin considering the strength of the remaining guard rod 8. From the standpoint of safety, it is better to have more guard rods 8 in the space 7 to prevent fingers from getting into it, and to make it smaller, but in this case, air resistance increases, resulting in negative effects such as a decrease in wind speed and an increase in noise. The second conventional example had this drawback.

In view of this point, the present invention aims to provide a manufacturing method that can simplify and rationalize the manufacturing process, significantly reduce material costs, and obtain products with uniform quality.

Below, one embodiment of the present invention will be described in Figures 5 to 1.
This will be explained using Figure 0.

Reference numeral 9 denotes a raw material, and pilot holes 9a and 9b are first drilled in this raw material 9 for shear cutting and splicing in a subsequent process. This drilling is performed intermittently once every two strokes of the press. Further, the pilot holes 9a and 9b are simultaneously drilled in a staggered manner at positions shifted by one pitch on the left and right with respect to the feeding direction. Next, the material is shear wire 10
Sheared by At this time, the shear line 10 is the pilot hole 11
Cut and join a and 11b, but the sheared comb teeth 1
2a is not cut off and is connected to the band edge 13a. Similarly, comb teeth 12 were sheared one pitch ago.
b is also connected to the band edge 13b. This shearing is done once per press stroke, and
Comb teeth 12a and 12b are made alternately on 3a and 13b. 14a and 14b are the band sides 1 in the next bending process.
3a and 13b after the first bending process. When the second bending process is further performed, the comb teeth 15a, 15b form a predetermined angle α° with the pair of the band sides, and the bending process is completed.

Reference numerals 16a and 16b are rubber-shaped parts that have been bent, and are approximately L-shaped facing each other, with comb teeth 17a and 17b and blanks 18a and 18
Looking at the relationship b, no scrap occurs because the material is simply separated by shearing, and the opposing comb teeth 20a, 20b and blanks 21a, 21b have the same width T. Furthermore, T is approximately equal to the material plate thickness T'. The comb-shaped parts 16a and 16b formed in the above manner are finally 19a and 19b.
It is cut along the line shown in . This cutting is also done intermittently, with 16 comb shapes every N strokes of the press.
Cut off a and 16b. In Figure 7, Com part 2
The total length l of 0 is given by the pitch T and the number of strokes N =
It is determined by N×T, and by selecting N and T, the required length l can be obtained. Furthermore, by changing the material width A, the width m of the comb component 20 can also be arbitrarily determined.

By bending the band side portion 21 of the comb component 20 thus obtained into a circular shape and simultaneously expanding the comb teeth 22 radially, the shaped portion 23 shown in FIG. 8 is obtained.
Both ends of the band side 21 are joined to form a small ring 24,
Further bend the guard rod 25 obtained from the comb teeth 9,
When processed, a half-guard shaped portion 26 shown in FIG. 9 is obtained. In FIG. 10, if the large ring 27 is joined to the half guard 26 by welding or the like and the mark stand 28 is attached, it becomes a guard for the electric fan.

As described above, according to this embodiment, the strip side 21 of the comb part 20 is obtained by performing co-cutting of the left and right parts of the comb part 20 simultaneously by using the intermittent movement of the punch by scraping press processing by shearing from a metal roll material. is bent into a circular shape to form a small ring 24, and the comb teeth 22 are expanded radially to form a guard rod 25.
Since it is manufactured by bending the plurality of guard rods 25 into a substantially L shape and fixing their tips to the large ring 27, the small ring 1 and the guard rod 3 are manufactured separately. The manufacturing process is simplified and streamlined compared to the conventional method shown in FIG. In addition, the uniformity of the product is higher than that of the conventional method, and above all, it is possible to achieve the effect of significantly reducing material costs due to improved material yield.

Note that in this embodiment, the pilot hole may have any other shape as long as it can be cut and spliced. Also, the obi sides 19a, 19b and the comb teeth 17a, 17
The angle α° with b is arbitrary.

As described above, the present invention can significantly reduce the material cost by performing the scrap press co-cutting process, and by producing the guard rod and small ring as one unit, the process and man-hours can be significantly reduced. It can be done, and its practical effects are great.

[Brief explanation of drawings]

Fig. 1 is a side view of an electric fan, Fig. 2 is a perspective view of a conventional electric fan guard, Fig. 3 is an exploded sectional view of a conventional electric fan guard, and Fig. 4 is a perspective view of a conventional press-formed guard. Fig. 5 is a perspective view of a material illustrating the processing process of the material by press working in one embodiment of the present invention, and Fig. 6 is a comb-shaped material showing the shape of the material after bending and the dimensional relationship of each part. FIG. 7 is a perspective view of the comb-shaped part, FIG. 8 is a perspective view of the developed part of the comb part, and FIG. 9 is a perspective view of the half-guard-shaped part after guard rod molding.
FIG. 0 is an exploded sectional view of a fan guard according to an embodiment of the present invention. 10...Shear wire, 11a, 11b...Prepared hole,
12a, 12b...comb teeth, 13a, 13b...band side, 16a, 16b...comb shaped part, 17a, 1
7b...Comb tooth, 19a, 19b...Shear line, 2
0... Comb parts, 21... Obi side, 22... Comb teeth,
24...Small ring, 25...Guard rod, 27...
large ring.

Claims (1)

[Claims] 1 A long material having a predetermined distance from both end faces on the left and right sides in the longitudinal direction, and staggered with a constant pitch in the longitudinal direction, and having a width in the longitudinal direction equal to the pitch, or a first step of providing a large pilot hole; a second step of cutting the material along a line connecting the pilot hole on one side and the pilot hole on the other side with a pitch equal to the pitch; a third step of cutting the material at a pitch equal to and along a line connecting the pilot hole on the other side and the next pilot hole extending in the longitudinal direction on the one side; and the second step. Repeating the third step sequentially to form a pair of band sides connecting one side of the comb teeth,
a step of dividing the material into two; a fourth step of forming the band side into a circular shape and forming comb teeth radially; and forming the comb teeth into a predetermined shape to form a guard rod;
and a fifth step of connecting the other ends of the guard rods with a large ring.