Method of manufacturing outer cutter of rotary electric shaver

Abstract

A method of manufacturing an outer cutter of a rotary electric shaver that includes the outer cutter and an inner cutter which is slidingly in contact with a bottom surface of the outer cutter and rotates, in which a plurality of the circular shaving surfaces are integrally formed in the outer cutter in a concentric manner, and round hole-shaped hair introduction openings are formed in at least one of the circular shaving surfaces includes (a) a step of grinding or polishing a predetermined position where the round hole-shaped hair introduction openings are formed in the circular shaving surface to obtain a thickness size smaller than an inner diameter size of the round hole; and (b) a step of forming the round hole-shaped hair introduction openings in the position where the grinding or the polishing is performed by pressing, after the step (a).

What is claimed is: 
     
         1 . A method of manufacturing an outer cutter of a rotary electric shaver that includes the outer cutter which has a circular shaving surface as a top surface where numerous hair introduction openings are formed and an inner cutter which has a small cutter slidingly in contact with a bottom surface of the outer cutter from below of the shaving surface and rotates, in which a plurality of the circular shaving surfaces are integrally formed in the outer cutter in a concentric manner, and round hole-shaped hair introduction openings are formed in at least one of the circular shaving surfaces, the method comprising:
 (a) a step of grinding or polishing a predetermined position where the round hole-shaped hair introduction openings are formed on the circular shaving surface to obtain a thickness size smaller than an inner diameter size of the round hole; and   (b) a step of forming the round hole-shaped hair introduction openings in the position where the grinding or the polishing is performed by pressing, after the step (a).   
     
     
         2 . The method of manufacturing an outer cutter of a rotary electric shaver according to  claim 1 ,
 wherein the step (b) is performed to form the round hole-shaped hair introduction openings that include the round holes at an inner periphery side and the round holes at an outer periphery side to be alternately disposed in a zigzag manner along a peripheral direction of the circular shaving surface.   
     
     
         3 . The method of manufacturing an outer cutter of a rotary electric shaver according to  claim 2 ,
 wherein, in the step (b), the pressing is performed to a plurality of round holes that are disposed at one of the inner periphery side or the outer periphery side by a single press, and then, the pressing is performed to the round holes that are disposed at the other one of the inner periphery side or the outer periphery side by the single press.   
     
     
         4 . The method of manufacturing an outer cutter of a rotary electric shaver according to  claim 1 , further comprising:
 (c) a step of forming slit-shaped hair introduction openings in a predetermined position of the circular shaving surface by the grinding, after the step (b).   
     
     
         5 . The method of manufacturing an outer cutter of a rotary electric shaver according to  claim 2 , further comprising:
 (c) a step of forming slit-shaped hair introduction openings in a predetermined position of the circular shaving surface by the grinding, after the step (b).   
     
     
         6 . The method of manufacturing an outer cutter of a rotary electric shaver according to  claim 3 , further comprising:
 (c) a step of forming slit-shaped hair introduction openings in a predetermined position of the circular shaving surface by the grinding, after the step (b).   
     
     
         7 . The method of manufacturing an outer cutter of a rotary electric shaver according to  claim 4 , further comprising:
 a step of forming a position mark in a predetermined position of the outer cutter before the step (b),   wherein processing is performed in each of the steps (b) and (c) taking the position mark as a common processing standard position.   
     
     
         8 . The method of manufacturing an outer cutter of a rotary electric shaver according to  claim 5 , further comprising:
 a step of forming a position mark in a predetermined position of the outer cutter before the step (b),   wherein processing is performed in each of the steps (b) and (c) taking the position mark as a common processing standard position.   
     
     
         9 . The method of manufacturing an outer cutter of a rotary electric shaver according to  claim 6 , further comprising:
 a step of forming a position mark in a predetermined position of the outer cutter before the step (b),   wherein processing is performed in each of the steps (b) and (c) taking the position mark as a common processing standard position.   
     
     
         10 . The method of manufacturing an outer cutter of a rotary electric shaver according to  claim 7 ,
 wherein the position mark is a D-shaped cut portion that is formed at an outer periphery edge of the outer cutter.   
     
     
         11 . The method of manufacturing an outer cutter of a rotary electric shaver according to  claim 8 ,
 wherein the position mark is a D-shaped cut portion that is formed at an outer periphery edge of the outer cutter.   
     
     
         12 . The method of manufacturing an outer cutter of a rotary electric shaver according to  claim 9 ,
 wherein the position mark is a D-shaped cut portion that is formed at an outer periphery edge of the outer cutter.   
     
     
         13 . The method of manufacturing an outer cutter of a rotary electric shaver according to  claim 4 ,
 wherein the round hole-shaped hair introduction openings and the slit-shaped hair introduction openings are formed to alternately provide a round hole forming area that is configured to have a predetermined number of round hole-shaped hair introduction openings and a slit forming area that is configured to have a predetermined number of slit-shaped hair introduction openings along the peripheral direction on a predetermined circular shaving surface by performing the steps (b) and (c).   
     
     
         14 . The method of manufacturing an outer cutter of a rotary electric shaver according to  claim 5 ,
 wherein the round hole-shaped hair introduction openings and the slit-shaped hair introduction openings are formed to alternately provide a round hole forming area that is configured to have a predetermined number of round hole-shaped hair introduction openings and a slit forming area that is configured to have a predetermined number of slit-shaped hair introduction openings along the peripheral direction on a predetermined circular shaving surface by performing the steps (b) and (c).   
     
     
         15 . The method of manufacturing an outer cutter of a rotary electric shaver according to  claim 6 ,
 wherein the round hole-shaped hair introduction openings and the slit-shaped hair introduction openings are formed to alternately provide a round hole forming area that is configured to have a predetermined number of round hole-shaped hair introduction openings and a slit forming area that is configured to have a predetermined number of slit-shaped hair introduction openings along the peripheral direction on a predetermined circular shaving surface by performing the steps (b) and (c).   
     
     
         16 . The method of manufacturing an outer cutter of a rotary electric shaver according to  claim 1 ,
 wherein the round hole-shaped hair introduction openings are formed in the circular shaving surface other than a outermost periphery.   
     
     
         17 . The method of manufacturing an outer cutter of a rotary electric shaver according to  claim 2 ,
 wherein the round hole-shaped hair introduction openings are formed in the circular shaving surface other than a outermost periphery.   
     
     
         18 . The method of manufacturing an outer cutter of a rotary electric shaver according to  claim 3 ,
 wherein the round hole-shaped hair introduction openings are formed in the circular shaving surface other than a outermost periphery.