JPS5834156B2 - Manufacturing method for inner blades for electric razors - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing an inner cutter for an electric shaver.

Conventional manufacturing methods of this type include (1) forming each inner blade as a single piece, (2) forming an inner blade body by combining a large number of blades and a frame, and (3) forming two inner blade bodies. The process is to combine them into a cylindrical shape and use a grindstone to grind the cutting edge of the blade into a cylindrical shape.

However, due to demands for miniaturization and improved performance of electric shavers, the inner blade 1°1
Some have notches 2, 2/ formed in /.

In other words, the ones in FIGS. 1 to 3 have grooves 4 on the outer cutter 3.
, and correspondingly each blade of the inner blade body 5 is formed.
A notch 2 is formed in . . . to form a three-dimensional slit 6, and with this structure, when shaving a long beard, the long beard is guided to the concave line 4 without being knocked down, thereby facilitating shaving.

In FIG. 3, 7 is a razor body, 8 is a driver, 9 is a bushing, 10 is a joint pin, 11 is a support spring, 12 is a switch, and 13 is a dustproof cap.

In addition, the ones shown in Figures 4 and 5 have cutouts 2/ on both sides of the inner blade 1/ to shorten the length in the width direction, making the overall razor body thinner and more compact. be.

However, when these inner cutting bodies 5, 5' are cylindrically ground, the edge 2a of the notch 2 is ground by the grindstone 14 as shown in FIG. There is a drawback that the degree of adhesion between the inner cutter and the outer cutter in the portion 2aK is poor and a gap is generated, which impairs the cutting quality.

Further, when centerless grinding the inner cutter body 5 with the grindstone 14, as shown in FIG. 7, a pressing force F1. F
2 is acting, the notch 2 has a shape similar to the three-dimensional slit 6.
There is a drawback that when the grindstone 14 makes contact at a portion without the notch 2 and when it makes contact at a portion without the notch 2, the inner cutter body 5 or the grindstone 14 fluctuates in the radial direction and vibrates, making it impossible to perform highly accurate grinding.

Therefore, an object of the present invention is to provide a method of manufacturing an inner cutter for an electric shaver that can eliminate all of these drawbacks.

A first embodiment of this invention will be explained with reference to FIGS. 8 to 11.

That is, this inner cutter manufacturing method is applied to a type in which notches for introducing long whiskers are formed, and the manufacturing process is performed according to FIG. 9.

That is, process A is a blade manufacturing process, in which a steel plate is punched out by press working to form a blade 15 as shown in FIG. A portion 19 is integrally provided.

The guide portion 19 forms a continuous arcuate edge having the same radius of curvature as the blade 150.

Step B is an inner blade forming step in which the inner blade 20 is assembled by simultaneously molding a large number of blades and a resin molded product.

■Process C is made by combining the flat parts of the two inner cutters 20 and 20' to form a cylinder, and as shown in Fig. 10, the adjustment wheel 21 and the support stand 2.
This is a grinding process in which cylindrical grinding is performed between the grindstone 2 and the grindstone 23.

The process involves a guide part removal process in which the guide part 19 of the valley blade is broken off and removed after grinding.

Note that since the remaining connecting portion 17 is not provided on an arc, it does not interfere with shaving and does not need to be removed, but it is desirable to remove it completely after grinding or the like.

With this configuration, the presence of the guide part prevents the edge 2a of the conventional notch 2 from being ground irregularly, resulting in good adhesion and sharpness. It is possible to prevent vibrations of the grindstone 23 or the inner cutter body 21 due to fluctuations, and achieve highly accurate grinding, thus all of the conventional drawbacks have been solved.

Furthermore, since the guide portion 19 is made of metal, the grinding wheel 2
3 has less clogging compared to the guide part 19 of the molded product.
Since the grinding resistance is the same as that of the blade part, the grinding becomes highly accurate.

The second embodiment of the present invention is applied to a type in which notches are formed on both sides of the inner cutter blade, and as shown in FIG. The blade 25 and the guide part 24 form one semicircular arc edge (indicated by the reference numeral), and the guide part 24 is removed after grinding, and the other steps are the same as in the first embodiment.

In the case of this embodiment, since the guide portions 24 are provided at at least two force points, there is an advantage that the effort required to remove the guide portions 24 is reduced, and the same effect as in the first embodiment is obtained.

As described above, in the method for manufacturing an inner cutter for an electric shaver of the present invention, a guide part that continuously forms a semicircular arc is provided in the notch of the flade, and the guide part is removed after grinding, so that the notch edge is irregular. Since no vibration is generated in the grindstone or the inner blade during grinding, the cutting quality is improved and the grinding accuracy is improved.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the outer cutter in its unfolded state, Fig. 2 is a perspective view of the inner cutter, Fig. 3 is a partially cutaway side view of the electric shaver, and Fig. 4 is a perspective view of another outer cutter in its unfolded state. Figure 5 is a perspective view of another inner cutter body, Figures 6 and 1 are side views of the grinding state, and Figure 8 is a perspective view of another inner cutter body.
The figure is a plan view of the blade of the first embodiment of this invention.
The figure is a process diagram, Figure 10 is a side view of the grinding state, Figure 11 is a partially enlarged side view, Figure 12 is a plan view of the blade of the second embodiment, and Figure 13 is a side view of the blade in the grinding state. It is a diagram. 15...Blade, 16...Notch, 1
9... Guide part, Aol,... Blade manufacturing process, B... Inner blade forming process, C... Grinding process, D... Guide part removal process.

Claims (1)

[Claims] 1. An inner blade body is formed by combining a Bunt production process in which an easily removed guide portion is provided in the notch of the inner blade to form a continuous semicircular arc shape, and a frame is combined with a large number of these blades. an electric cutting process that includes an inner blade forming process, a grinding process of combining two of these inner blade bodies and cylindrical grinding of the cutting edge of the inner blade, and a guide part conventional process of removing the forward guide part after this grinding process. A method of manufacturing an inner blade for a razor. 2. The method of manufacturing an inner cutter for an electric shaver according to claim 1, wherein the guide portion is made of metal. 3. The method of manufacturing an inner cutter for an electric shaver according to claim 1 or 2, wherein the guide portion is formed at at least two locations.