| 摘要 |
PURPOSE: To provide a method to prevent development of yarn breakages during acceleration without impairing operability by lowering draw ratio during low speed operation and acceleration, and after reaching a specified speed, raising the draw ratio between arbitrary sections by a specified time rate. CONSTITUTION: When a yarn 1 is to be drawn between a roll 4A and a roll 4B by driving control of driving electric motors 3A, 3B set up in plural sections A, B, respectively, the daughter machine section A is operated at a low draw ratio via a draw ratio setter 141 for low speed during low speed operation or acceleration, thus avoiding yarn breakages due to excessive tension development. When a relevant detective circuit 15 detects that the parent machine section B reaches a specified low speed value, the draw ratio is switched from the output from the setter 141 for low speed to that from a second draw ratio setter 142 for high speed by the operation of a switching circuit 16 via an AND circuit 17 and a switching command circuit 18, and a drawing operation is carried out at a specified production rate. |
