PURPOSE: To prevent the uneven flow of ended cocoons and to improve the efficiency of automatic reeling operation, by changing the circulation flow rate of water for moving ended cocoons in the reeling tank to flow them evenly and smoothly.

CONSTITUTION: The adjusting plate 10 to adjust the opening of a suitable number of holes 9 on the press plate 8 from its full width to the complete closing is attached to the bottom plate 7 via the long holes 21 and screws 22. The holes 9 at a position where the water flow is great are partly opened to suppress the water flow compared with the wholly closed position. Thus, the circulation flow is uniformed over the total length of the tank 1. The reeling cocoons will not be broken in the ended parts, and the efficiency of automatic reeling operation is improved without excessive concentration or uneven distribution.