Belt driving mechanism for blower of cooling tower

A belt transmission mechanism for a cooling tower blower that uses a flat belt as a transmission belt for a blower, and has an appropriately-positioned tension-adjusting part that keeps the belt aligned, thereby preventing the belt from falling off and making the belt maintenance free, while improving the efficiency of the driving of an impeller. Specifically, the flat belt is used as a transmission belt 13, which stretches between a drive-side pulley 11 and a driven-side pulley 12. A tension-adjusting part 14, which holds the belt 13 by means of a tension pulley 14d that is in contact with the belt 13 so that the belt 13 does not flex, is designed to have the function of keeping the belt 13 aligned while traveling. Furthermore, since the rotation center position of the tension pulley 14d is located near the driven-side pulley 12, the belt 13 can be appropriately controlled by the tension pulley 14d of the tension-adjusting part 14, and by suppressing misalignment of the belt 13, even if the travel direction