PROBLEM TO BE SOLVED: To reduce the production cost of a combine by making the transmission device of a feed chain as an inexpensive one, and also keeping the feed chain in stable speed so as to perform threshing work smoothly.SOLUTION: This feed chain (1) is constituted so as to be driven by the transmission from a stepwise transmission device (2) equipped with transmission ranges having 2 steps of high speed and low speed or more. Based on standard vehicle speed set previously, the stepwise transmission device (2) is constituted to be transmission-controlled so that the stepwise transmission device (2) is switched to a high speed transmission range in a transmission process to the high speed traveling side of a stepless transmission device (3) changing vehicle speed as stepless, and also the stepwise transmission device (2) is switched to a low speed transmission range in the transmission process to the low speed traveling side of the stepless transmission device (3).COPYRIGHT: (C)2008,JPO&INPIT【課題】フィードチェンの変速装置を安価なものとしてコンバインの製造コストを低減すると共に、フィードチェンを安定した速度に保持して脱穀作業を円滑に行なえるものとする。【解決手段】フィードチェン(1)を高速と低速との二段階あるいはそれ以上の変速域を備えた有段式変速装置(2)からの伝動によって駆動すべく構成する。そして、車速を無段階に変速することのできる無段式変速装置(3)の高速走行側への変速過程で有段式変速装置(2)を高速変速域に切り換え、無段式変速装置(3)の低速走行側への変速過程で有段式変速装置(2)を低速変速域に切り換えるように、それぞれ予め設定した基準車速に基づいて有段式変速装置(2)を変速制御するように構成する。【選択図】 図20
