| 摘要 |
PURPOSE:To enable a smooth control of speed reduction and shock-reduced stopping action to be attained, by connecting a drain port of a driving motor, which drives an object to be indexed, to a line in the preceding position of a speed reducing variable orifice. CONSTITUTION:A delivery side pressure is applied acting on a drain port 60 of a driving motor 1 which drives an indexed object 4. When the indexed object 4 reduces its speed, that is, when a variable throttle 47 or 48 of a flow direction control valve 14 is changed to a small opening side, the delivery side pressure rises by inertia of the indexed object 4 by a variable orifice 49 comprising lines 44, 40, 46, 32, connecting the driving motor 1 to a tank, and a bypass throttle 45. Accordingly, decreasing pressure difference between a pressure of fluid, circulating in the driving motor 1, and the drain port 60 and reducing the proportion of the drain amount of working fluid supplied to the driving motor 1, the control characteristic improves in the time of supplying a fine amount of flow in a speed reduction process. In this way, performing a smooth control of speed reduction, shockless stopping action can be attained. |
