| 摘要 |
<p>Conditional exchanging of working fluid between plural fluid circuits (13A, 13B) having separate supply pumps (18A, 18B) is provided for without continuously bleeding fluid from the pump control pressure lines (21A, 21B). Each circuit (13A, 13B) has a pump control (19A, 19B) responsive to a control pressure, a plurality of fluid motors (14A, 15A, 16A, 14B, 15B, 16B), and a group of resolver valves (38A, 38B) which compare motor pressures and intercommunicate the pump control (19A, 19B) with the most highly pressurized motor (14A, 15A, 16A, 14B, 15B, 16B). At times when fluid from one circuit (13A, 13B) is being delivered to a motor (16A, 16B) of another circuit (13A, 13B), the pressure comparing function of the resolver group (38A, 38B) of the one circuit (13A, 13B) is extended to include the motor (16A, 16B) of the circuit (13A, 13B). Among other uses, the system (11) may be used on excavator vehicles having plural fluid motors performing a variety of different functions. Absence of a bleed in the pump control lines (21 A, 21B) conserves power and enables precise response of the pumps to demand changes. </p> |
