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Publication numberUS352647 A
Publication typeGrant
Publication dateNov 16, 1886
Publication numberUS 352647 A, US 352647A, US-A-352647, US352647 A, US352647A
InventorsJohn J. Ghegan
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Automatic electric liquid-level indicator
US 352647 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

(No Model.)



No. 352,647. Patented Nov. 16,1886.





, srscrrrcA'r-r'on forniingpartoi' Letters Patent 'No. 352,647 dated November 1c. 1886.

Application tiled May 29, 1886.

IO My invention relates to indicatorsor alarms for low water in tanks-such as reservoirs,

' boilers, and similar containing-vessels,

The object is to provide a device operating entirely by means located without the vessel containing the water, and yet being of. such a nature asto beindependent of jars vibrations, or shocks communicated to the vessel.

It consists in the application of a piece of selenium to liquid-level indicators or alarms,

so that when the water becomes low rays of light will fall upon the selenium, which by electrical means causes a signal to be given. In order to illustrate the practical manner of. carrying out the invention, and to enable others to construct and use the same, a drawing is hereunto annexed and described, in which similar characters of reference represent corresponding elements.

The liquid-level indicator consists of the 0 combination of a source of,.lightsuch, for

instance, as a lamp'A, a shield or screen, B, in whose opening is a condensing-1ens, C, a containing-tube, l), of glass, which may be considered as having liquid or pipe connect-ions E with a boiler or tank, F, a .float, G, made of opaque material-such as sheet metalor of a'cork or piece of wood, said floatbeing within the tube, and a piece; ofselenium, H-,

upon the opposite side of the tube .fromthe- 0 lamp, and in thesame horizontal line with the flame -ofthe lamp, the'selenium beingin an electric circuit of, constant and preadjusted qresistance, andincluding an electric bell, I.

A funnel or ray-collector, L, is provided op-" 5 posite the." lens 0. .-In the normal condition the water J in the tube is of such a depth that the float cuts off the rays K of light from falling upon the selenium, sothat thecircuit remains practically ofuniform resistance; but

W-hen the water sipks the float also sinks and Serial No. 203,614. (No model.)

the rays fall upon the selenium, diminishing the resistance so much that the current in the circuit becomes strong enough to ring the bell or to operate any similar translating device.

I The invention is not limited to the precise con-' structior hereinbefore described and shown,

as stated in'S'pragues Electricity, its Sources and Applications, page '10, the resistance of a piece of selenium varied through four hundred megoh ms in being taken 'from a dark room into a gaslightedroom. '1

Having now stated the object of the said invention, having described its praoticalrealizationbyreference to the accompanying drawing, andhaving particularly ascertained the Y manner in which the same operates to accom- 1 plish the said object,what I consider to be novel and original, and therefore claim as 'myinven 'tion, is

1. The'combinatiouof a source of light, a

translucent vessel containing a liquid, and a piece of selenium forming part of an electric circuit, including a translating device, suba described.

2. In-an automatic liquid-indicator, the combination' of a source of light, a condensinglen's, a liquid translucent containing' vessel, an

stantially for the purpose and in the manner opaquefloatin said vessel,,a piece of selenium,

and an electric circuit including a translating devicefsuch as anelectric signal, said source of light, lens, float, and selenium lying nor mally in an approximately straightline.

3. Inan automatic liquid-level indicator, the combination of a source of light, a liquid translucent containing-vessel, an opaque float therein, and a piece of selenium forming'part device, such as an electric signal,'-'s'aid'float being normally between said source of light and said selenium;

4. In a liquid-levelindicator,the combina- Eco of an electric circuit containlng a translating I tidn of a lamp, 0. double convex lens attached Witness my signature and seal this 24th thereto, a liquid-containing vessel, a. funnelof May,'1886.

shaped month fixed upon the side of said vessel, an opaque float. in said vessel, 9. piece of JOHN J. GHEGAN. [L. s.] 5 selenium, and an elebtsiqcircnit containing an f j elctric bell, said lamp,'lens, funnel, float, and Witnesses: selenium being normally inan approximately" EDWARD P. THOMPSON, straightline, asand for the purpose described. M. H. Torrme.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2490627 *Jun 30, 1945Dec 6, 1949Rca CorpPhotoelectric liquid level indicator
US2621808 *Aug 22, 1946Dec 16, 1952Frazier SimplexApparatus responsive to variations in liquid level
US2805652 *May 1, 1953Sep 10, 1957Stout Minor WWater level responsive controls for combustion apparatus
US2891241 *Dec 31, 1954Jun 16, 1959Gisholt Machine CoUnbalance tolerance limit inspection machine
US4014010 *Aug 1, 1975Mar 22, 1977Walter Joseph JinottiFluid-dispensing apparatus having level control and alarm means
US4445238 *Sep 29, 1982May 1, 1984Maxhimer Monroe RSwimming pool water level control apparatus
US4984462 *May 30, 1989Jan 15, 1991Meditor CorporationDetachable liquid level monitoring apparatus and method
US5743135 *Feb 10, 1995Apr 28, 1998Vlsi Technology, Inc.Optical-fiber liquid-level monitor
Cooperative ClassificationG01F23/2921