| 摘要 |
PURPOSE:To provide a device which can drop pressurized molten solder accurately at a constant rate by forming the middle chamber of three chambers which are segmented to upper, middle and lower, to the volume of the desired amt. for one solder dropping and operating a valve stem communicating through the respective chambers vertically and plural valves alternately. CONSTITUTION:Part of the molten solder in an upper chamber 14 is put into a middle chamber 24 by opening an upper valve 13. After this, the valve 13 is closed and a lower valve 23 is opened to drop a required amt. of the molten solder in the chamber 24 through a lower chamber 34 from a nozzle 12. At this time, a non-oxidative gas such as N2 or Ar is injected under a high pressure of 2-4kg/cm<2> through the high pressure gas conduit 43a of the valve stem 23 on the inner side to clean the molten solder stagnating or stuck in the chamber 34 and the nozzle 12. With this device, it is possible to control the rate of dropping of the molten solder at a constant rate with the volume in the middle chamber withot strict regulation of the opening and closing times for the valves. |
