JPH0212594B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing an outer cutter used for a rotary electric shaver, etc., and in particular, a thin metal plate is pressure-welded to a mold having a large number of repeated convex portions and concave portions, and the shape of the concave portions is determined. This invention relates to a method for producing an outer cutter, which involves forming a large number of rib-equivalent portions and hole-equivalent portions on a thin metal plate by deforming the thin metal plate along the same direction, and then polishing and removing the bottom portions of the hole-equivalent portions to form hair insertion holes having an annular peripheral wall. It is something.

FIGS. 1 and 2 are diagrams for explaining this type of conventional manufacturing method.

As shown in FIG. 1, a large number of convex portions 2 forming portions corresponding to ribs and recesses 3 forming portions corresponding to holes are provided in a predetermined arrangement on the surface of a mold 1. A thin metal plate 4 made of a stainless steel plate having a thickness of about 35 to 45 μm is placed on the mold 1, and the thin metal plate 4 is pressed into the mold 1 by a freely deformable pressing member 5 made of urethane rubber or the like. Pressed.
Through this pressure welding, the parts of the thin metal plate 4 facing each of the recesses 3 of the mold 1 are pressed and deformed along the shape of the recesses 3, and as shown in FIG. The portion 7 is formed repeatedly.

Then, by polishing and removing the bottom portion 8 of each hole-corresponding portion 7 as shown by the dashed line A, a hair insertion hole 10 having an annular peripheral wall 9 is formed.

However, in this conventional method, when the thin metal plate 4 is partially deformed along the shape of the recess 3 by the pressing force of the pressing member 5, the portion of the thin metal plate 4 facing the recess 3 is stretched. It deforms, but since the opposing parts are continuous, it deforms while a mutual pulling force acts on it internally. Therefore, cracks occur during the process of forming the hole-equivalent portions 7 and remain on the peripheral wall 9, resulting in product defects.

An object of the present invention is to eliminate such drawbacks of the prior art and provide a method for manufacturing a high quality outer cutter.

In order to achieve this object, the present invention provides a protrusion that penetrates the bottom of the hole-equivalent portion of the thin metal plate on the inside of each recess of the mold, and when the thin metal plate is pressed against the mold, the bottom of the hole-equivalent portion is pressed against the protrusion. It is characterized by breaking through at a certain point.

Next, one embodiment of the present invention will be described with reference to FIGS. 3 to 6.

As shown in FIGS. 3 and 4, the surface of the mold 1 has convex portions 2 for forming rib-equivalent portions 6.
A large number of recesses 3 for forming hole-equivalent portions 7 are provided in a predetermined arrangement. A pin-shaped projection 11 having approximately the same height as the projection 2 is formed in the center of each recess 3 .

As shown in FIG. 4, a deformable thin metal plate 4 made of a stainless steel plate is placed on top of the mold 1, and a freely deformable pressing member 5 made of urethane rubber, solder, etc. is pressed against the mold 1. Through this pressure welding, the portion of the thin metal plate 4 facing each recess 3 of the mold 1 is pressed and deformed along the shape of the recess 3, but at this time, the hole-corresponding portion 7
The center of the bottom part is pierced by the projection 11, and a through hole 12 is formed in the bottom part 8 as shown in FIG. If the through hole 12 is formed in the bottom part 8 of the hole-equivalent part 4 in the middle of forming it, that is, if a part of the bottom part 8 is pierced, the thin metal plate 4 can be moved into the mold 1.
Since it can be easily brought into close contact with the inner surface of the recess, and almost no undue stress is applied, there is no occurrence of cracks as in the conventional case. FIG. 5 shows a state in which the forming of the metal thin plate 4 has been completed.

After forming a large number of rib-equivalent portions 6 and hole-equivalent portions 7 on the thin metal plate 4, it is taken out from the mold 1 and the sixth
As shown in the figure, if the bottom part 8 of each hole-corresponding part 7 is polished and removed as shown by the dashed line A, an annular peripheral wall 9 will be formed.
A beard insertion hole 10 having a diameter is formed. If the through holes 12 are formed in the bottom 8 during polishing, the polishing liquid will flow better and the polishing resistance will be reduced, which will improve the polishing ability and reduce the occurrence of burrs.

The present invention has the above-described configuration, and cracks do not occur when forming the hole-equivalent portion by press-forming the thin metal plate to become the outer cutter, thereby reducing the defective rate. High quality outer blades can be manufactured. Further, it has the advantage that the polishing ability is improved and the generation of burrs is reduced when removing the portion corresponding to the hole by polishing.

[Brief explanation of drawings]

1 and 2 are cross-sectional views for explaining a conventional outer cutter manufacturing method, and FIGS. 3 to 6 are for explaining an outer cutter manufacturing method according to an embodiment of the present invention. FIG. 3 is a perspective view of the mold used in the example, FIG. 4 is a sectional view showing the state before press forming of the thin metal plate, FIG. 5 is a sectional view showing the state after forming the metal thin plate, and FIG. FIG. 6 is a sectional view showing the polishing process of the formed thin metal plate. 1... Mold, 2... Convex part, 3... Concave part, 4...
Thin metal plate, 5... Pressing member, 6... Part equivalent to rib, 7... Part equivalent to hole, 8... Bottom, 9... Peripheral wall, 10... Mustache insertion hole, 11... Protrusion, 12...
...Through hole, A...Polishing position.

Claims (1)

[Claims] 1 A deformable thin metal plate is pressed against a mold in which a large number of convex portions forming rib-equivalent portions and recessed portions forming hole-equivalent portions are repeatedly provided, and ribs are formed on the thin metal plate by deforming it along the shape of the recesses. In the method for manufacturing an outer blade of an electric shaver, in which a large number of corresponding portions and hole-equivalent portions are formed, and then the bottom of the hole-equivalent portions is polished away to form a hair insertion hole having an annular peripheral wall, the inner side of each recess of the mold is A method for manufacturing an outer blade for an electric shaver, characterized in that a protrusion is provided to break through the bottom of a hole-equivalent portion of a thin metal plate, and the protrusion pierces the bottom of the hole-equivalent portion when the thin metal plate is pressed into a mold.