| 摘要 |
<p>PURPOSE:To reduce the length of bolts for use in installing cases of a plurality of oil passage shifting control valves on an oil passage-carrying pump casing in a communicated relationship, by fastening the control valves in series directly to the pump casing with bolts. CONSTITUTION:A hydraulic circuit in a portable rice-planting machine is adapted to supply a hydraulic pressure from a hydraulic pump 25 to an antiwheel-lifting control valve 22 first , and then to a wheel-lifting control valve 19 only when the control valve 22 is in a neutral state. In this hydraulic structure, a transmission case 2 is utilized as a tank, and the control valves 19, 22 are installed on a side wall of the transmission case 2. In more detail, a pump casing 26 and the control valve 22 are fastened to a side wall of the transmission case 2 with bolts 27, and the control valve 19 is then fastened to the control valve 22 with bolts 28. Owing to this structure, the length of connecting bolts can be reduced.</p> |
