| 摘要 |
<p>1,191,760. Making dry shaver shear plates. CARINTHIA ELEKTROGERATE G.m.b.H. 24 Dec., 1968 [25 March, 1968], No. 61425/68. Heading B3A. [Also in Divisions B4 and C7] A perforated shear-plate for dry shavers comprises a main body 1 made from steel foil and having a network forming bridges 2 between the holes 1 so as to provide rims 3 which are flanged and ground, the main body of the shear plate consisting substantially of a soft, hardenable steel, whereas in the region of the flanged and ground rims of the holes, the material has a sub-microscopic, over-quenched martensitic structure containing residual austenite. The shear-plate is produced by first stamping a strip of steel containing at least 5% carbon, the strip being stamped to produce several shearplates. The strip is then mounted on the periphery of a massive metal drum with the flanges facing outwardly, the drum then being rotated slowly and the strip thrust against the surface of a rapidly-rotating disc of high-speed steel which grinds the strip and also causes an abrupt development of heat in the region of the rims 3. As soon as the required temperature is reached, the strip is cooled by the mass of metal in the drum. The surfaces of the rims are simultaneously ground during the heating process. The strip of foil is finally separated into individual shear-plates.</p> |
