JPH0359985B2 - - Google Patents

Description

[Detailed description of the invention] 〔Technical field〕 The present invention relates to an outer blade for an electric razor.

[Prior art]

Conventionally, in order to improve the sharpness of electric razors and extend the life of the sharpness, it has been known to form a hard coating on the cutting edge of the outer blade. Typical examples of this hard coating include hard wet plating such as hard chromium and hard nickel phosphorus. However, since these films also have a Bitkers hardness of 1000 (Kg/mm) or less, the lifespan of the outer cutter is currently 1 to 2 years after normal use.

As a countermeasure to this problem, forming a titanium nitride film using the ion plating method has been considered, but there have been problems with poor adhesion between the metal substrate and the film, resulting in peeling, and the possibility of forming an ultra-hard film directly on the metal material. The problem is that when a strong bending stress is applied to an ultra-hard coating, cracks tend to form in the ultra-hard coating, and the cracks can reach the metal substrate.Also, there is the problem that the coating becomes brittle due to the processing heat during ion plating. There was a problem.

[Purpose] The present invention is intended to solve this problem, and its purpose is to form a hard coating that has a coating structure that has good adhesion to metal materials and is resistant to cracks due to bending, and also to form a hard coating that is difficult to crack due to bending. The aim is to prevent embrittlement due to processing, improve sharpness with a hard coating, and significantly extend the life of the outer blade.

〔overview〕

The outer cutter for an electric razor of the present invention has a metal substrate with a large number of through holes, a metal titanium layer and a titanium nitride layer on the surface of the metal substrate, and a metal titanium layer and a titanium nitride layer formed on the surface of the metal substrate. The ion plating method is used so that the thickness ratio between the layers is 5:5 to 9:1.
This outer blade for an electric razor is characterized by being formed with a thickness of ~2.0μ.

〔Example〕

Hereinafter, the present invention will be described in detail based on examples.

FIG. 1 is a cross-sectional layout diagram of a conventional outer cutter and inner cutter for an electric razor, and FIG. 2 is an enlarged cross-sectional view of the skeleton of the outer cutter according to the present invention.

In FIG. 1, reference numeral 1 is a cross-sectional view of the skeleton of the outer cutter, and reference numeral 2 is a cross-sectional view of the inner cutter, which cuts hair introduced through the through hole by moving the cutter at high speed in the direction of the arrow. In FIG. 2, 3 is a titanium layer subjected to ion plating, and 4 is a titanium nitride layer.

In Fig. 2, the material of the metal substrate 1 is 13Cr.
Stainless steel, Ni, Ni-Co materials, etc. are used.
When titanium nitride 4 is directly formed on this,
It is very easy to peel off, and when bending stress is applied, cracks in the titanium nitride layer reach the metal substrate 1, causing cracks in the substrate itself. Therefore, the above-mentioned problem is solved by inserting a titanium layer 3 as an intermediate layer. The total thickness of the titanium layer and titanium nitride layer must be 0.2μ or more to ensure the minimum wear resistance of the outer cutter, and 2μ or less to prevent peeling and cracking. is necessary. The optimum value here is 1μ. Further, the ratio of the thickness of the titanium layer to the titanium nitride layer in the range of 5:5 to 9:1 has excellent practical characteristics, and in particular, 8:2 is optimal. If the titanium layer is thinner than 5:5, peeling and cracking will easily occur, and if the titanium layer is thicker than 9:1, dents and the like will easily form on the surface due to external forces.

Although various known methods can be used for the above-mentioned ion plating method, the temperature of the metal substrate increases to 300° C. or higher no matter which method is used. When a normal Ni substrate made by electroforming is used as the metal substrate, the Ni contains a brightening agent.
Since 0.08% or more of S is added, there is a problem that the material becomes brittle. In order to solve this problem, it is necessary to limit the amount of S added and compensate for the decrease in hardness due to the decrease in S by adding Co. In order to have the minimum strength,
With a composition of 20wt% Co, 0.01wt% S, and the balance Ni.
Ensure Hv=400 or higher with Co and S, and reduce the amount of S to prevent deterioration of heat resistance.

On the other hand, 40wt% Co, 0.001wt% S and the balance
Regarding the Ni component, the basic strength is secured mainly by Co alone, and Hv=450 or higher. 0.001wt%
S is the lower limit amount that naturally eutectoids. this
20~40wt% Co, 0.01~0.001wt% S and balance
To manufacture the outer cutter made of Ni, nickel sulfamate, cobalt sulfamate, boric acid,
A sulfamic acid bath containing nickel chloride as the main component is most suitable. By forming two layers of the above film on a metal substrate with this composition, there is no embrittlement caused by heat.
In this case, since it is formed by ion plating, the adhesion of the film to the substrate is extremely high.
It is possible to provide an outer cutter with extremely high surface hardness, good cutting ability, and high durability.

〔effect〕

As described above, according to the present invention, on a normal metal substrate or a metal substrate with a limited composition,
By forming titanium and titanium nitride in a certain thickness and proportion, it is possible to create an outer cutter that is hard to peel off, hard to crack from the surface, and has good sharpness and long life without becoming brittle due to heating. Ta.

In particular, for the outer blade for electric razors, in order to improve the contact with the skin, the entire outer blade is required to be highly flexible and capable of deformation, rather than being a rigid body.
In addition, in order to cut hairs short (deep shaving properties), it is desirable that the outer blade be thin, but as in the present invention, a metal titanium layer and a titanium nitride layer are sequentially formed on the surface of the metal base material of the outer blade. , 0.2 to 2.0μ in total
Since it is formed to a thickness of 1,000 yen, the above-mentioned flexibility and deep shaving properties are not impaired in any way, and the surface hardness is significantly increased, sharpness is improved, and the tool life is extended. In this case, since the thickness ratio of the metal titanium layer and the titanium nitride layer is 5:5 to 9:1, even if the outer blade deforms against the skin as described above, the metal base material The titanium layer acts as a binder and the titanium nitride layer does not peel off, and since the titanium nitride layer is moderately thick, it will not dent even if the outer blade hits your skin or hits other hard objects. Therefore, it is possible to provide an electric razor outer blade that is completely excellent in practical use without causing any damage.

In particular, although the thickness ratio of the metal titanium layer and the titanium nitride layer is 5:5 to 9:1, as in the case where the metal titanium layer is thinner than 5:5, the outer cutter may When the outer cutter is deformed as mentioned above, the titanium nitride layer will not peel off from the metal substrate and cracks will not occur, and when the metal titanium layer is thicker than 9:1 and the hard nitride layer is thin. Similarly, when a hard object hits the outer cutter surface, no dents are formed on the outer cutter surface, and the outer cutter has excellent functions and effects unique to the outer cutter of an electric razor.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional layout diagram of an outer cutter and an inner cutter for a conventional electric razor. FIG. 2 is an enlarged cross-sectional view of the skeleton of the outer cutter according to the present invention. DESCRIPTION OF SYMBOLS 1... A cross-sectional view of the skeleton of the outer blade body, 2... A cross-sectional view of the inner blade body, 3... Titanium layer, 4... Titanium nitride layer.

Claims (1)

[Claims] 1. A large number of through holes are formed in a metal substrate, and a metal titanium layer and a titanium nitride layer are sequentially formed on the surface of the metal substrate. In total, the ion plating method is used so that the thickness ratio is 5:5 to 9:1.
An outer blade for an electric razor characterized by being formed with a thickness of 0.2 to 2.0μ. 2. In the outer blade for an electric razor according to claim 1, the metal substrate with a large number of through holes is made of 20 to 40 wt% of Co, 0.01 to 0.01 by electroforming.
An outer blade for an electric razor characterized by using a substrate of a Ni-based alloy consisting of 0.001wt% S and the balance Ni.