JPS6116464B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to an outer cutter for an electric razor.

Generally, outer blades for electric razors are made by electrodeposition, and as shown in FIG. 5A, for example, as shown in FIG. An arbitrary metal electrodeposition layer 13 is formed on the exposed substrate 12 between the resin layers 11 in the metal substrate 12, and this layer 13 is formed on the exposed substrate 12 between the resin layers 11.
When the thickness reaches the thickness of 1 or more, a peeling treatment is performed, and a normal nickel electrodeposited layer 14 constituting the outer cutter is provided thereon, and the electrodeposited layer 13 is then peeled off.
By peeling it off, it becomes a net blade having a large number of hair introduction holes 15 and a band-shaped protrusion 16 around the holes as shown in FIG. 3B.

The electric razor cuts the hair introduced through the hole 15 of the net blade by sliding an inner blade made of stainless steel, which is harder than the net blade, on the tip surface 17 of the protrusion 16. At this time, there is a close relationship between the surface condition of the tip face 17 and the sliding resistance of the inner cutter, and if the surface is rough and has large irregularities, the sliding resistance tends to be large, and this is due to the driving torque of the inner cutter. This results in not only an increase in heat but also an increase in sliding heat.

By the way, the inventors discovered that conventional outer cutters made by the above-mentioned method often suffer from fractures such as cracks and cracks during use, and that the cross-sectional structure of the broken outer cutters was separately heat-treated at 230°C. It is very similar to the cross-sectional structure of the outer cutter, which means that the breakage of the outer cutter during use as described above is mainly caused by the heat of sliding, and there is a risk that this will occur when this heat becomes higher than 230℃. It has been found that there is a large

Therefore, it is desirable that the tip surface 17, that is, the surface on which the inner cutter slides, be made as smooth as possible to reduce the sliding resistance.
However, the tip surface 17 immediately after electrodeposition molding is as shown in FIG. 5A.
As can be seen from the figure, the surface condition of the resin layer 11 appears as it is, and since the surface of this layer is generally rough, it is extremely difficult to make it a desired smooth surface. Conventionally, therefore, chemical or mechanical smoothing treatment has been performed after electrodeposition molding, but such treatment is not only troublesome, but also does not necessarily provide sufficient effects.

This invention was discovered as a result of intensive studies in light of the above circumstances, and will be described below with reference to the drawings.

1 and 2 are main part sectional views showing an example of an outer cutter for an electric razor according to the present invention. Reference numeral 1 denotes an outer cutter base body made of, for example, nickel electrodeposition and having a band-shaped protrusion 2; A metal layer 5 having a melting point of 230° C. or lower is provided on a surface 4 on which the inner cutter 3 slides.

After the base body 1 is formed by the method shown in FIGS. 5A and 5B, the metal layer 5 is formed on the sliding surface 4 by vacuum deposition such as ion plating or ion sputtering. A specific example of a metal with a melting point (mp) of 230°C or lower is wood alloy (mp72
), Newton alloy (mp 94℃), rose alloy (mp 100℃), solder (mp 180~220℃), indium (mp 156.4℃), etc.

According to this configuration, the inner cutter 3 slides along the surface of the metal layer 5, and if the surface of this layer is rough, it exhibits sliding resistance close to that of a conventional outer cutter without the metal layer 5 at the beginning of use. As the material softens due to the heat of sliding, the above resistance rapidly decreases. What is important is that such softening of the metal layer 5 occurs in a low temperature range of 230° C. or lower, and the rapid decrease in sliding resistance at this time prevents the sliding heat from rising above the above temperature.

On the other hand, the softening of the metal layer 5 promotes abrasion or scraping by the inner cutter 3, and the outer cutter base 1, more specifically, is worn down to the position of the protrusion 6 on the sliding surface 4 within a relatively short period of time. . FIG. 3 shows this state. When the softened metal layer 5 is press-fitted into the recess 7 by the sliding inner cutter 3, the sliding surface 4 becomes almost smooth and there is no sliding resistance. remains constant thereafter.

FIG. 4 shows an example of such a change in sliding resistance over time, and the curve - is for the electric razor of the present invention in which a 2μ thick solder is provided as a metal layer 5 on a 120μ thick outer blade base 1. For the outer cutter, the curve −
This is the case of a conventional outer cutter that is not provided with such a metal layer 5. The sliding resistance was calculated by examining the change in current consumption after the stainless steel inner blade was rotated and slid against the outer blade at a pressure of 40 g and a rotational speed of 5000 rpm.

As is clear from the figure, the initial sliding resistance of the outer cutter of the present invention rapidly decreases, and it can be seen that a very low resistance value is obtained compared to the conventional outer cutter. The thickness of the metal layer 5 necessary to achieve such an effect varies depending on the surface condition of the sliding surface 4 of the outer blade base 1, but is usually 0.1μ or more, and this layer thickness is If it is too thick, the sliding resistance may increase and it may also have a negative effect on hair cutting, so it is generally 0.1~
A layer thickness of about 3 μm is desirable.

As described above, this invention is a method in which a metal layer with a low melting point of 230°C or less is provided on the surface of the outer blade base on which the inner cutter slides, and as another technical means different from this invention. There are products that have a synthetic resin layer with good lubricity such as polypropylene resin or acetal resin on the above surface, but compared to this, there is no material change or peeling phenomenon such as oxidation reaction of the resin layer due to the heat of sliding. In addition, the metal layer can be formed as an extremely thin layer, which reduces sliding resistance without reducing cutting quality, which reduces the sliding heat that causes toughness destruction such as cracks and cracks, and also reduces the inner cutting edge. This has the effect of reducing driving torque.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a main part of the outer cutter for an electric razor of the present invention, Fig. 2 is an enlarged view of the portion shown in Fig. 1, and Fig. 3 is a wear of the metal layer during use of the outer cutter for an electric shaver of the present invention. FIG. 4 is a characteristic diagram showing an example of the change in sliding resistance over time. FIGS. FIG. 1...Outer blade base, 3...Inner blade, 4...Sliding surface,
5...Metal layer. Curve: In the case of the outer blade for an electric razor of the present invention, Curve: In the case of the conventional outer blade for an electric razor.

Claims (1)

[Claims] 1. Surface 4 on which inner cutter 3 slides on outer cutter base 1
An outer blade for an electric razor, characterized in that a metal layer 5 having a melting point of 230°C or lower is provided. 2. The outer blade for an electric razor according to claim 1, wherein the metal layer 5 has a thickness of 0.1 to 3 μm.