| 摘要 |
<p>PURPOSE:To smoothly switch the confluence and improve operability by providing a confluence valve on a confluence circuit communicated between inflow circuits of two variable pumps and operating it when the flow of the pump on the service valve connection side is made full. CONSTITUTION:A confluence valve 17 made of an electromagnetic proportion type flow control valve is arranged on a confluence circuit 16 communicated between inflow circuits 3F and 3R of two variable pumps 2F and 2R. When the confluence is judged to be necessary based on the necessary flow of a special attachment, a confluence switching electric switch 21 is turned on, the confluence flow is set on a volume 22, then a service valve operating lever 23 is varied. In this case, the confluence valve 17 is kept in the closed state until the flow of the variable pump 2F on the connection side of a service valve 15 is made full, a bleed-off valve 20R on the confluence side is closed and the confluence valve 17 is opened when the flow is made full, and the necessary flows from both pumps 2F and 2R are merged.</p> |
