PROBLEM TO BE SOLVED: To provide a transmission applied to a service vehicle having a driving source and a right-and-left pair of a first and a second crawler type running devices, in which the difference of a driving rotation number between a right-and-left pair of a first and a second output axes can be made large so that a spin turn can be expressed and the cost is reduced and the size is made small by the reduced parts count.SOLUTION: A transmission is provided with: a differential 23 capable of differentially transmitting a rotation power input from a gear case to a first and a second output shafts 22 (1), 22(2) and a speed increasing device 24 capable of transmitting the rotation power input from the gear case to the first and the second output shafts to increase the speed. The speed increasing device has a first and a second speed increase conduction paths 50 (1), 50 (2) capable of transmitting the rotation power of an input gear 41 of the differential to which the rotation power is differentially input from the gear case to the first and the second output shafts in a synchronous state to increase the speed, and a first and a second multiplate type clutches 51 (1), 51 (2) are respectively inserted into the first and second speed increase conduction paths.COPYRIGHT: (C)2013,JPO&INPIT【課題】駆動源及び左右一対の第1及び第2クローラ式走行装置を有する作業車輌に適用されるトランスミッションにおいて、スピンターンを現出させ得るように左右一対の第1及び第2出力軸の駆動回転数差を大きくとり得る共に、部品点数の削減によるコスト低廉化及び小型化を図る。【解決手段】変速装置から入力される回転動力を第1及び第2出力軸22(1),22(2)へ差動伝達可能な差動装置23と、変速装置から入力される回転動力を第1及び第2出力軸に増速伝達可能な増速装置24とを備え、増速装置は、変速装置から作動的に回転動力を入力する差動装置の入力ギヤ41の回転動力を第1及び第2出力軸に同期状態で増速伝達可能な第1及び第2増速伝動経路50(1),50(2)を有し、第1及び第2増速伝動経路にはそれぞれ第1及び第2多板式クラッチ51(1),51(2)が介挿される。【選択図】図3
