Method of abrading both sides of work piece

摘要

The method of the present invention is capable of abrading a work piece (25) with fixed load. The method comprises: a first abrading process, in which pressure of a cylinder chamber (16a) of a cylinder unit (16) suspending an upper abrasive plate (14) is adjusted so as to apply first pressure to the work piece (25) via the upper abrasive plate (14) without applying full weight of the upper abrasive plate (14); and a second abrading process, in which the pressure of the cylinder chamber (16a) is readjusted so as to apply second pressure, which is higher than the first pressure, to the work piece (25) via the upper abrasive plate (14) without applying the full weight of the upper abrasive plate (14). The method may further comprise a third step in which the pressure applied to the work piece is less than the second pressure (see fig 5). The upper abrasive plate may be provided on its upper face with a reinforcing rib 37; the upper abrasive plate may be connected to a rod 18 of the cylinder unit by means of a holding disc 20 and a plurality of connecting rods 21 which may be fixed to the holding disc 20 or may be suspended from it by means of elastic members such as coil springs (35 fig 6).