| 摘要 |
An automatic strapping apparatus is disclosed which forms a small primary loop from strap; expands the primary loop to a larger predetermined diameter loop which can be placed about a package to be strapped; and tensions, friction fuses, and severs the strap. The small primary strap loop is formed by feeding a free end of a length of strap into a circular cup through a slot in the cup sidewall so that the free end is guided by the inner periphery of the cup to form a loop with the strap free end overlapping a portion of the loop. The cup is moveable from an upper position around the formed primary loop to a position out of contact with, and below, the loop. A cylindrical gripper is provided inside the loop and a smooth-surfaced anvil is provided on the exterior of the loop for engaging the overlapped portion of the loop therebetween so that the strap free end is restrained by the gripper while the overlapped portion of the loop can be continued to be fed to expand the loop to a larger predetermined diameter. The strap free end remains restrained by the gripper as the strap is tensioned to tighten the loop about the package. The gripper is then rotatably oscillated at a high frequency to cause the strap free end to slide against the overlapped portion of the loop thereby generating heat and fusing the strap free end to the overlapped portion of the strap loop. A cutter is provided to sever the tightened and fused loop from the standing length of strap.
|
