PNALYTICAL EDITION
MAY 15, 1937
249
Siphon-Starting Device
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4411 I I
E
T. W. CHANDLER, Rayon Department, E. I. du Pont de Nemours & Co., Inc., Buffalo, N. Y.
T
HE starting of a siphon, particularly with corrosive
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I ‘ FIGURE 1. WIRINGDETAILS
liquids in an open container, often cannot ,be achieved conveniently and safely by expedients commonly used. Siphoning from a wide-mouthed bottle, pail, or drum may present such dficulty, and to meet this condition in handling a corrosive solution the device shown in Figure 1 was made. Essentially, the apparatus consists of a siphon centered in a reservoir tube, of sufficient capacity to fill and start the siphon by pressure on the liquid in the reservoir. A rubber stopper around the bottom of the larger tube acts to seal the reservoir until the siphon has been started; then tilting the assembly allows the siphon to drain the container. A flat disk of gasket rubber placed on the bottom of the containing vessel may help to form a better seal while the siphon is being started. The drawing is self-explanatory, except that it does not indicate the relation between the tube sizes. The length of the siphon and height of the reservoir are determined by the container with which they are t o be used. If it is assumed that the length of the siphon is three times the height of the reservoir, and if the reservoir is to provide four times the volume of the siphon tube, the relationship of the inside tube diameters is: D = &@, where D is the diameter of the reservoir and d is bhe diameter of the siphon. These relationships provide for sufficient reservoir capacity t o ensure an excess of liquid over that just sufficient to start the siphon.
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FIGURE 2. PANEL MOUNTING, FRONT VIEW desirable. It does not regulate in the sense of keeping down voltage fluctuations in the main line supply. Unlike a rheostat, there is no ower lost in heat; all the current is used in producing the effect &sired and regulation is closer than with the average rheostat. On this instrument, 4 binding posts are mounted on the panel to furnish current for a hot wire loop for glass cutting. They are connected to any successive 10-turn taps of the transformer, thus giving voltages from 3 to 20, depending on the position of the 7-point rotary switch. This device has been in constant service in the laboratory for two years and has given entire satisfaction.
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Pressure bulb 0riginal)evel of liquid Reservoir tube F. Tube centering rubber stopper L. Rubber stopper as gasket N. Bottom of container R. Tube centering rubber stopper cut out to permit flow i n t i siphon
A. B. C.
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FIGURE 1. DEVICEFOR STARTING SIPHONIN-OPEN VESSELS
Literature Cited (1) American Radio Relay League, Hartford, Conn., “Radio Amateurs’ Handbook,” 2nd ed., pp. 130-6, 1927. (2) Chemical Rubber Publishing Co., Cleveland, Ohio, “Handbook of Chemistry and Physics, 21st ed., 1936. (3) Greenleaf, A. R., Camera, Vol. L. No. 3,155 (1935). (4) Technical Service Bureau, Inc., Chicago, Ill., Tech. Bull. D-111.
If the liquid level is too low to provide a volume great enough to fill the siphon tube, suction may be applied to fill the reservoir tube before the pressure is applied to start the siphon. A tee with vacuum connection and pressure bulb attached could well be provided if the need is anticipated.
B.ECIIVED Maroh 16, 1937
RECEIVED February
20, 1937.
