| 摘要 |
PURPOSE:To make manufacture and assembly ever so easy, by constituting a pump casing part, forming a gear chamber of a hydraulic pump, and a control valve casing part housing each control valve solidly as one body, and setting up a gear shaft axis and an axis of a valve hole for control valve use in parallel with each other. CONSTITUTION:A boarding and alighting arm to be installed in before and behind parts of a farm tractor is controlled up and down by each hydraulic cylinder at the before and behind parts to be controlled by a hydraulic control unit 25. In this case, this hydraulic control unit 25 is constituted of a hydraulic pump 33 and a control valve gear 34 being set up as adjoined to each other in both directions of the tractor, and both 33 and 34 are installed so as to use a casing 35 in common. That is to say, the hydraulic pump 33 is constituted of a pair of pump gears 39 and 40 being housed in a gear chamber 38 in a pump casing part 35 and engaged with each other. In addition, the control valve gear 34 is constituted of a selector valve 55 selecting actuations of each hydraulic cylinder, a manual valve 56, a relief valve or the like, and housed in the control valve casing part 35a.
|
