| 摘要 |
<p>A rinsing tank in a developing machine for X-ray films or the like is equipped with a circulating system which draws liquid from the bottom zone of the tank and returns the withdrawn liquid to the upper zone of the tank. The contents of the tank can be evacuated without resorting to any values by using a siphon whose intake end is connected with the suction side of a jet pump in the pipeline for circulation of liquid, the uppermost section of which is located at a level below the normal level of the upper surface of the body of liquid in the tank, and the discharge end of which is connected with a liquid removing pipe. When the pump which causes the liquid to circulate by flowing through the pipeline is arrested, the jet pump is deactivated and allows the liquid in the siphon to rise and to flow into the uppermost section. The liquid thereupon continues to leave the tank in the form of a continuous stream which flows along a second path defined by a portion of the pipeline, the jet pump and the siphon. If the operator wishes to interrupt the evacuation of liquid from the tank, an aerating valve is caused to admit air into the uppermost section of the siphon and to thus break the continuous stream of outflowing liquid. In normal operation, the upper surface of the column of liquid in that section of the siphon which connects the suction side of the jet pump with the uppermost section is located below the uppermost section. The jet pump is installed at a level below the bottom zone of the tank, and the pump which circulates the liquid is located at a level above such bottom zone but below the normal level of the upper surface of the body of liquid in the tank.</p> |
