| 摘要 |
PURPOSE:To prevent a bound object from being damaged in a device for cutting a packing strap, by moving a wedge-like lower cutter depressed to the surface of the bound object at a back clearance angle and by making the back clearance angle zero when a strap position is detected and the strap is picked up. CONSTITUTION:A sliding member 11 is moved by the rotation of a screw shaft 12; the front edge of a wedge-like cutter 13 is slided along recesses and projections on the surface of a bound object seeking for a strap 1, and when the strap 1 is detected, the front edge of the lower cutter 13 is coupled with the strap 1. During this sliding for detection, the front edge of the lower cutter 13 maintains a back clearance angle alpha (about 15 deg.) in relation to the surface of the bound object. Next, when the sliding member 11 is moved to the left under a slight resistance, a link pin sliding piece 17, together with a link pin 19, is moved elastically to the right in a guide groove 23 against a spring 18, and links 16A, 16B are rotated clockwise so that the back clearance angle alpha of the lower cutter 13 is made zero. As a result, when the strap is picked up at the next step, the surface of the bound object can be prevented from being scratched by the front edge of the lower cutter 13 at a strong pressure. |
