. . "closed by way of example in the following description and in the accompanying drawings in which Figure 1 is a vertical section of the pick-up device; Figure 2 is a section on the line 2--2 of Figure 1; Figure 3 is a detail perspective view of the screw guide; a Figure 4 is a plan view; a Figure 5 is a detail plan view of the collector 1 ring and track; Figure 6 is a section on the line 6--6 of Fig" . .