| 摘要 |
PURPOSE:To prevent a V-belt from slipping and wearing, by providing a tension pulley located on the loose part of the V-belt and movable by an appropriate operation in such a direction as to make the belt tight or loose and by using a spring to urge the pulley in such a direction as to tighten the belt. CONSTITUTION:A tension pulley 43 is provided on the inside of the loose part of a V-belt 42. A spring 46 is provided between a holder 4 and a lever 45 integrated with an arm 44, to cause the tension pulley 43 to always tighten the V-belt 42. When a rice planter is quickly moved down and a planting clutch is engaged, the spring 46 acts to prevent the phenomenon that the tension of the V-belt 42 based on the tension pulley 43 would be removed all at once due to the sharp loosening of a release wire 47. The belt 42 is thus kept from loosening. As the effective diameter of a split pulley 34 slowly becomes large due to the action of a spring 38, the spring 46 is elongated to prevent V-belt 42 from vibrating. As a result, the V-belt 42 does not slip on the pulley 34 and another pulley 41, so that a secure transmission of motive power is effected and the V-belt does not wear. |
