WIRE-SAW FOR CUTTING WAFER FROM BAR OR BLOCK-LIKE WORKPIECE

PURPOSE: To very accurately cut a wafer even when a workpiece format changes by additionally and respectively arranging a single undriven auxiliary guide roller on both sides of the wire part in contact with a workpiece between deflective rollers to demarcate a sawing area. CONSTITUTION: At least a single undriven auxiliary guide roller 5 is also arranged on both sides of the wire part 3 to contact with a workpiece between deflective rollers 4 to demarcate a sawing area to impart an additional deflection angle on a wire 3 by copying after it. This deflection angle is an angle existing between the virtual extension part of the wire part to move on the auxiliary guide roller 5 and the deflective part of the wire passing through the auxiliary guide roller. In most cases, a reliable guide of the wire is no more guaranteed at a deflection angle less than 1 deg., so that the fact that force generated at a deflection angle larger than about 30 deg. generally demands no more justifiable cost of a device, is known.