JPS6231957B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a reciprocating electric shaver blade, and its purpose is to provide a reciprocating electric shaver blade that improves the adhesion between the outer cutter and the inner cutter and provides a sharper cut. Our goal is to provide the following.

The outer cutter plate 3 of the reciprocating electric shaver is flexible, and when the outer cutter plate 3 is bent into a substantially U-shaped cross section, the outer cutter plate 3 bends in the bending direction X, as shown in FIG. The linearity in the perpendicular direction Y is not maintained, and the central portion is recessed by the amount of recess (δ), resulting in a so-called saddle shape.
As a result, the inner cutter, which is made up of a large number of blades that reciprocate in sliding contact with the inner surface of the outer cutter plate 3, is uniformly moved in the direction Y (hereinafter referred to as the inner cutter reciprocating direction) orthogonal to the bending direction X of the outer cutter plate 3. Since they do not touch each other, the cutting quality of the whiskers at the Y end in the reciprocating direction of the inner blade is poor.

Mechanically analyzing such a saddle-shaped curve, if the curvature of the saddle-shaped curve is Vx, the bending moment applied to the end is Mx, the bending rigidity of the plate is D, and the Poisson's ratio of the plate is γ, then 1/Vx = Mx /D(1- ^γ2 ) Therefore, in order to reduce the amount of depression (δ), it is sufficient to increase Vx.

The present invention has been made in view of the above study results, and will be described below with reference to the drawings showing embodiments of the present invention. In Figures 1 to 3, the outer blade 1
It is composed of an outer cutter plate 3 in which a large number of whisker introduction holes 2 are bored in a flexible metal thin plate, and an outer cutter base 4 that holds the end of the outer cutter plate 3. A pair of locking square holes 5 are formed at each end of the outer cutter plate 3, and an engaging protrusion 6 into which the locking square hole 5 is inserted is formed on the inner surface of the outer cutter base 4. It is installed protrudingly.
The whisker introduction hole 2 is formed by the outer cutter crosspiece 7.
The inner cutter 8 is composed of a plurality of inner cutter blades 9 that reciprocate in sliding contact with the inner surface of the outer cutter plate 3, and an inner cutter base 10 on which the inner cutter blades 9 are arranged side by side. (not shown) to a reciprocating drive rod 11. In FIG. 4, a region A with large deflection in a direction crossing the reciprocating direction Y of the inner cutter 8
The outer cutter plate 3 is provided with small deflection regions B alternately, and the small deflection regions B are arranged symmetrically with respect to a direction X that intersects each other and is orthogonal to the reciprocating direction Y of the inner cutter 8.

As a method to reduce the deflection, as shown in FIG. 5, the size of the hair introduction hole 2 is made smaller, and as shown in FIG. However, it is desirable to adopt two methods to continuously change the stiffness without impairing the introduction of whiskers. Figure 7 shows the reciprocating direction Y of the inner cutter 8 at the apex when the outer cutter plate 3 is bent.
This is a graph showing the amount of dent (δ) in , compared to the conventional one shown by the solid line, where areas B with small deflection are alternately arranged in the direction The amount of dent (δ) in the region B with small deflection shown by the diagonal line is small, and as shown by the dashed line, the amount of dent (δ) at the maximum difference position is about 1/3 of that of the conventional one. Furthermore, if the distance between the region A with large deflection and the region B with small deflection is set densely at both ends of the outer cutter plate 3 in the inner cutter reciprocating direction Y of the outer cutter plate 3, and sparsely at the center, the amount of dent ( δ) changes continuously as shown by the broken line in FIG. 7, and the state of close contact with the inner cutter 8 becomes stable.

As described above, the reciprocating electric shaver blade of the present invention has a flexible outer cutter plate having a plurality of hair introduction holes and a substantially U-shaped cross section, and an inner cutter plate that slides on the inner surface of the outer cutter plate and reciprocates. In the reciprocating electric shaver blade, the outer cutter plate is provided with areas of large deflection and areas of small deflection alternately in a direction crossing the reciprocating direction of the inner cutter, and the outer cutter plate has small deflection areas. This feature is characterized in that the regions intersect with each other and are arranged symmetrically with respect to a direction perpendicular to the reciprocating direction of the inner cutter, so it has the following effects.

(1) The bending of the inner cutter of the outer cutter plate near the center in the reciprocating direction is reduced, correcting the saddle-shaped curvature, which improves the adhesion between the outer cutter and the inner cutter, and improves hair cutting performance. There is.

(2) Hair that is not introduced into the beard introduction hole in an area with small deflection will be introduced into the beard introduction hole in an area with large deflection due to the movement of the reciprocating electric razor during shaving, impairing the introduction of the beard. This has the effect of making it possible to create an outer blade plate that does not have a similar shape.

(3) The rigidity in the direction perpendicular to the reciprocating direction of the inner cutter may be too large compared to an outer cutter plate in which regions of small deflection and regions of large deflection are arranged alternately in the reciprocating direction of the inner cutter. Since it can be bent to fit closely against the inner blade, it has the effect of providing a good cutting edge.

(4) Compared to an outer cutter plate in which the area of small deflection and the area of large deflection are inclined in one direction, even if the outer cutter plate is bent, the outer cutter plate is perpendicular to the bending direction and the outer cutter plate is tilted in opposite directions. This has the effect that both ends of the board are not bent into a twisted state, and the cutting ability is good without impairing the close contact with the inner cutter.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the curved state of the outer cutter plate that is the subject of the present invention, FIG. 2 is an exploded perspective view of a reciprocating blade that is an embodiment of the present invention, FIG.
The figure is a plan view of the outer cutter plate, FIGS. 5 and 6 are enlarged views of the outer cutter plate showing a method of providing a region with small deflection, and FIG. 7 is a graph showing the amount of deflection. 2... Beard introduction hole, 3... Outer cutter plate, 8... Inner cutter, 9...
Inner cutter grade, Y...Direction of reciprocating inner cutter movement, A...area with large deflection, B...area with small deflection.

Claims (1)

[Claims] 1. A reciprocating electric shaver blade comprising a flexible outer cutter plate having a plurality of hair introduction holes and having a substantially U-shaped cross section, and an inner cutter that slides in contact with the inner surface of the outer cutter plate and moves back and forth, Regions of large deflection and regions of small deflection are alternately provided on the outer cutter plate in a direction crossing the reciprocating direction of the inner cutter, and regions of small deflection are arranged so as to intersect with each other and perpendicular to the reciprocating direction of the inner cutter. A reciprocating electric razor blade characterized in that the blades are arranged symmetrically with respect to the direction in which the razor blades are shaved.