RISE AND FALL CONTROL DEVICE IN AGRICULTURAL TRACTOR

摘要

PURPOSE: To provide a rise and fall control device in an agricultural tractor capable of accurately controlling height of a working machine in spite of being a simple mechanism. ;CONSTITUTION: In an agricultural tractor in which a working machine is liftably attached to the rear of a machine body, the working machine is raised and fallen by a hydraulic device and a manual operating means, a detector fitted to the working machine and a feed back mechanism are connected through a link mechanism to a control valve of the hydraulic device so as to control ground height of the working device, the link mechanism is constituted in such a way that a link base 11 is laid between an upper rise and fall control link 27 whose one end is coupled with the manual operating means and a lower position link 28 and the links are connected by a support pin 30. A lower part 28a of difference in level is formed at the other side of the position link 28. The characteristics of the objective rise and fall control device in an agricultural tractor is that a sensor arm 24 linked and connected to the detector for discovering the ground height of the working machine is hung from the low part 28a of difference in level of the position link 28 and is coupled with the rise and fall control link 27.;COPYRIGHT: (C)1995,JPO