PROBLEM TO BE SOLVED: To solve problems wherein works for attaching or detaching raisers are troublesome and the maintenance is not easy.SOLUTION: The driving shaft 32 and output shaft 33 of the raiser 8 are divided. The raiser 8 is supported on a lower lateral frame 37 in a state capable of being longitudinally rotated on the lower lateral frame 37 as a fulcrum. The upper portion of the raiser 8 is backward inclined, whereby the output shaft 33 is connected to the driving shaft 32 in a driving force-transmittable state and in a state that the upper side attaching or detaching means 47 is attached to an upper lateral transmission cylinder 35, and the lower side engaging means 65 becomes in a state incapable of being attached or detached from the lower lateral frame 37. The upper portion of the raiser 8 is forward inclined to separate the upper side attaching or detaching means 47, whereby the output shaft 33 is separated from the driving shaft 32 in a state shutting-down the transmission, and the lower side engaging means 65 can be attached or detached.COPYRIGHT: (C)2012,JPO&INPIT【課題】引起装置の着脱作業が面倒であり、メンテナンスが容易でなかった。【解決手段】引起装置8の駆動軸32と出力軸33とを分割する。引起装置8は下部横枠37を支点に前後回動自在な状態で下部横枠37に支持し、引起装置8の上部を後方に傾動させて上側着脱手段47を上部横伝動筒35に取付けた状態で前記出力軸33および駆動軸32が駆動力を伝達可能な状態になると共に、下側係合手段65が前記下部横枠37より着脱不能な状態になる構成とし、前記引起装置8の上部を前方に傾動させることで前記上側着脱手段47を離間させて出力軸33と駆動軸32とが分離され、伝動が遮断された状態になると共に、前記下側係合手段65が着脱可能となる構成とする。【選択図】図6