PROBLEM TO BE SOLVED: To provide an agricultural machine transmission that is high in cooling efficiency.SOLUTION: An agricultural machine includes a three point link hitch mechanism 2, a transmission gear box 3 receiving power from a PTO shaft of a tractor, and a rotary working part 4 attached with plowing blades 12 around the shaft periphery of a rotating shaft 11 extending horizontally. The transmission gear box 3 has a drive shaft 17 and a driven shaft 18. Gearshifts 191 and 192 are provided at the rear end side of the drive shaft 17 and the driven shaft 18 in an insertable and replaceable manner. Power is transmitted from the drive shaft to the driven shaft to perform tillage or mowing work. The agricultural machine includes an oil stirring member 26 attached to the drive shaft 17 or the driven shaft 18, an oil stirring cooling support case 5 forming a space for receiving oil along with the transmission gear box 3, and heat radiation fins 6 provided on an outer surface of the support case 5.COPYRIGHT: (C)2015,JPO&INPIT【課題】冷却効率の高い農作業機の変速装置を提供すること。【解決手段】3点リンクヒッチ機構2と、トラクタのPTO軸から動力を受ける変速ギヤボックス3と、水平方向に延びる回転軸11の軸周に耕耘刃12を装着されるロータリ作業部4と、を備え、変速ギヤボックス3は、駆動軸17と従動軸18とを有し、駆動軸17及び従動軸18の後端側にチェンジギヤ191及び192を挿入差替え可能に設け、駆動軸17から従動軸18に動力を伝達し、耕耘作業又は草刈り作業を行う農作業機において、駆動軸17又は従動軸18に取付けられるオイル撹拌用部材26と、変速ギヤボックス3と共にオイルを収容する空間を形成するオイル撹拌冷却用の支持ケース5と、支持ケース5の外面に設けられる放熱用のフィン6と、を備える。【選択図】図1
