Patent ID: 7228855
Filing Date: 2007-06-12
Classification: B23D,B28D,Y10T

Abstract:
1. A method for cutting a single crystal ingot using a band saw type cutting machine comprising a pair of pulleys ( 17 , 17 ) rotating around their respective central, vertical axes ( 17 a , 17 a ) which are separated from each other by a specified distance with an endless belt-like blade ( 18 ) being tightly wound around the rims of those pulleys ( 17 , 17 ), wherein the blade is made to run a circuit via the rotation of pulleys ( 17 , 17 ), a single crystal ingot (IOa) is arranged below a straight running portion ( 18 a ) of the blade such that the longitudinal axis of the ingot (IOa) crosses at right angles with the straight running portion ( 18 a ) of the blade, and the pair of pulleys ( 17 , 17 ) are allowed to descend vertically so that the straight running portion ( 18 a ) of the blade is brought into contact with ingot (IOa) below to cut the latter, wherein the method comprises the steps of: setting the straight running portion ( pre-cutting the ingot (IOa) with the straight running portion ( detecting a shift (A) from the lowermost position of the cut surface (IOb) of the pre-cut ingot (IOa) to the lowermost position obtained by projecting a first line vertically from the uppermost part of the cut surface (IOb); adjusting an inclined angle of the straight running portion ( continuing, after the adjustment of the inclined angle of the straight running portion (