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Publication numberUS1703880 A
Publication typeGrant
Publication dateMar 5, 1929
Filing dateDec 30, 1924
Publication numberUS 1703880 A, US 1703880A, US-A-1703880, US1703880 A, US1703880A
InventorsChester S. Gordon
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
US 1703880 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

Mar. 5, 1929. l c, s, GQRDaN 1,703,880

THERMOSCOPE Filed D80. 50, 1924 20 Y Ll) ATTORNEY Patented Mar. 5, 1929.




Application led December 30, 1924. Serial No. 758,898.

, This invention relates to thermoscopic instruments for indicating temperature ranges in melted substances, and more particularly in substances such as paraffin or the like.

. An object of the invention consists in the provision of a thermoscope having contained elements which will function at predeter- V mined ranges to indicate when the desired temperature range is reached in heating substances.

Another object consists in providing an instrument of this character of such ruggedness as to render it practically free from breakage.

Other and further objects will be apparentfrom the following description, when considered in connection with the accompanyingdrawing, in which one embodiment of the invention is illustrated.

. Referring to the drawing, in which 'like characters of referencejdesignate like parts throughout, Figure 1 is a perspective view of the improved device, Fig. 2 is a front elevation thereof, and Fig. 3 is a side view of Fig.- 2. The metal parts of this arrangement are lpreferably composed of rust-proof and noncorrosive materials, and, in the drawing, the numeral 5 represents a hollow, rectangular lcasing which may be nickel-plated. The casing 5 is provided with a dat back portion 6 having two lat side portions 7 and a bottom portion 8 which extend forwardly therefrom. The corners of the casing 5 are preferably rounded, and the front portions 9 are turned a short distance inwardly toward leach other from the side 7 so that there is a comparatively wide space provided 1n thefront of the casing to provide a sightopening between the adjacent edges of the portions 9. y

'A carrier 10 is slidably positioned within the hollow casing 5 in such manner that it may be easily inserted in or withdrawn from said casing through the open upper end thereof. The carrier is provided with a flat portion 11from the upper part of which two integral lugs 12, and from the lower part of which two corresponding lugs 13, extend forwardly. The edges 14 on each side of the portion 11, lying between they Vupper lugs 12 and lower lugs 13, are turned backwardly so that the depth presented by the forwardly extending lugsn and back= wardly extending portions provide sides for gible.

the carrier 12 of such dimensions to just permit the slidable engagement of said carrier with the channel portions formed between the front portions 9 and the interior back wall of the casing 5. In the drawing, two plates 15 are indicated as affixed respectively to the sides of the lower lugs 13. These plates extend downwardly from said lugs and are provided for the purpose of forming a bumper to limit the descent of the carrier 10 into the casing.

A pair of parallel glass tubes 16 and 17 are longitudinally mounted on the, face of stance, as illustrated by means of wires 18 Awhich encircle the tubes near their upper and lower extremities. The ends of these wires extend through openings in the carrier into the chamber 19, provided between t-he back of said carrier and the interior back wall of the casing 5. Y The ends of each pair of wires are then twisted so as to firmly retain the tubes in position. The upper parts of the tubes may be extended to form tips (as more clearly indicated in Fig. 3) which extend through holes in the carrier and serve to more rigidly position thc tubes on said carrier. The sight-opening in the face of the casing between the longitudinal edges of the portions 9 is such as to permit a full view of the mounted tubes so that the action of their contents may be readily observed. The lower parts of the tubes have the usual enlarged globular portions which contain the ingredients which respond to temperature changes, and, in order that these may be more clearly visualized, openings 25 are provided through the rear wall of the casing directly behind the globular portions. The casing may have slots provided at either side of the globular portions to permit the entrance of light to facilitate the observation of their contents. The casing affords protection to the tubesI by providing a partial enclosure therefor so that they are not subjected to outside contact and thus breakage thereof is negli- A handle, which may be composed of hard wood, is provided for the improved arrangement, and this is shown as having a surface 20 so formed as to be readily grasped by the hand. A centrall portion 21`is formed in.

the top edges of the casing; and extending vvriff-"die, is detachedtherefromso that the car-y `rier`may be readily slipped out throughthe V:opentop ott-he casing.

' "The 'chemicalcompounds Aused m the glass tubes dare-.selected so that melting points will l 20' occur at predetermined temperatures and these elements may consist of organic or inorganic/salts, or alloys. rlhese ingredients *obta-in' desired ineltingrpoints in the respec- "Q3-tive tubes. "For eXample,iii it is desired that *the contents'ofthe'tubes shall respond respectively `to temperatures oitI 375 Fahrennitrate lmayfbe nsedfrThus, to obtain in one fftube amelting` point at 375 1F., thexsalts are J.mixed in approximatelythe following pro- Y 9 portions: 85%,si-lver nitrate, and 15% thalf'lium nitrate.v To iobta-in inthe other tube a "meltinlgrv point OBQOOFx, the `salts are mixed 35 inappro'ximatelythe following proportions 'l 90% silvernitrate1 andg10%` thallium nitrate.

"Ilius,1-the LV'desired Ytemperatures of thev melted substance, for instance, paraffin, are.

yfindica-ted bythe salt 'crystals changing into 0 v a clearliquidtvhenmelted. ,On eoohng,the

-l-saltsfreturn tofthe'crystalline term and they performance maybe repeated Without any change inf? themeltingpoints.

It Will be` umlerstoodthat sullicient `sub- 145? stance iscontained.With-inthe tubes to make fit readilyvisible' in both unmelted and melt-- edlconditions.- lThe substances inthe tubes in their normalyco'ol statepresent an opaque appearance,` which changes into a clear liq- 505' uid: st atewhensubjected/to the proper tem- -perature i The contents of tube 16 4will Vv'changeltrom an opaquestateto a clear liquid 2state when .subjected to a temperature ot' f1390O/F. andthe coiitentsot tube 17 will 55* `change'fromlan opaque state to awclear liquid state when subjectedr to if-temperature of 3750 F. 'The provision ofI the improved structure with the tubes mounted therein, as

.above 4fdeseribed,' ii''urnishes a. very i convenf 60,- ient :form et thermoscope :for determining ther-temperature. of .heated compounds, Vsuch 4as -paraitinl or'theilifke. The easingtorms a covering Which protects the tubes from f brealmgfe andf the .sight opening permits? the M2-state of the substances in the tubes to be` ing. The portiony 22 extends Within `theV readily observed. Although other containers tor the chemical compounds may be used, it has been found convenient to employ `tubes of the characterl indicated-toi.' this purpose. These tubes `ail'ord goed visibility, may be mounted in the casing in a conven- .ientn'ianncig and may be readily removed Athe minimum 4tempeinturc is indicated by the normally lopaque substance in tube Y1.7 becoming clear, and when thetemperature reaches 23900 F., the maximum temperature is indicated by the substance in the lube lG becoming clear. rllherefore, the temperature olfthe compound or-parallhi--may he readily determined by removing the thermoscope from the compound orparallin if fnecessary, `and notingthe condition of the substance Ain tubes `16 and 17 throughlhe sight opening 4in `the casing. lVhen the `heated compound or paraffin reachesthe desired temperaturerange, as--p^reviously indica'ted, it is iii-proper condition-to be applied to :insulated electric conductors.

\ From vthe foregoing, it is thought that the construction, operation and many Aadvantages ot' ythe herein-described and delineated invention Will be apparent to those yskilled inthe art without riturther descripit-ion, and itWill-be understood that various changes inthe size, shape,proportion and minor-details lof construction, as yWell as changes in the -proportionalparts ot #the ingredients may be resorted tor-Without departing l'rom thespirit or sacrilicing' any -ot the `advantagcsoflthe invention, as delined` in the appended claims.

1. fithermoscope'comprising a. casing, a carrier mounted-therein, aahandle forming a cap for said casing and exteiulingithercin to prevent longitudinal movement ofsaid /carrier, a pair oftubcs mounted-on said carrier having contained chemical compound elcments of like ingredients, but ol' different proportions, respectively, theelcmens being apportioned in said tubes to respond to predetermined temperature ranges to respectivelyl indicatesthe maximum and .minimum heat conditions-in melted substances.

y2. A ,thermosoopecomprising a casing, a carrier mounted therein, parallel tubes mounted onsaidearrier, each tube having silver nitrate and .thalliuinnitrate of difflerent proportions contained therein to respond respectively to predetermined ranges vin temperature ot `melted subi-dances, thc ingredients in one ot said tubes heine*y 'fusible at a temperature of approximately 375 degrees Fahrenheit to indicate the minimum heat condition in the melted substance, and the ingredients in the other tube being usible at a temperature of 390 degrees Fahrenheit to indicate the vmaximum heat conditions in melted substances.

3. A thermoscope comprising a casing, a carrier mounted therein, parallel tubes mounted on said carrier, each tube having ingredients thereinto respond respectively to predetermined ranges in temperature of melted substances, the ingredients in one tube comprising silver nitrate of approximately 85% and thallium nitrate of approximately 15%, and the ingredients in the second tube comprising silver nitrate of a` roximately 90% and thalliuin nitrate of agroximately 10%, the ingredients in said first tube being fusible at a temperature of approximately 37 5 degrees Fahrenheit to indicate a minimum heat condition in the melted substance, and the ingredients in the second tube being fusible at a temperature of approximately 390 degrees Fahrenheit to indicate a maximum heat condition in the melted substance.

4. A thermoscope comprising an elongated casing of substantially rectangular shape having flanges extending longitudinally of its front side to provide a sight-opening between the edges of said flanges, Isaid casing having a substantially closed bottom portion and an open top portion, a carrier mounted in the casing, said carrier comprising a flat portion having extensions forwardly andv rearwardly thereof to respectively engage the flange portions and rear portions of said casing to permit a slidable engagement of the carrier into position in the casing, parallel tubes mounted on the carrier in a position to be visualized through the sightopening, and a handle alixed to the upper portion of the casing and extending therein to prevent the longitudinal movement of said carrier.

In testimony whereof, I have signed my name to this specication this 26th day of December, A1924.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
USRE34515 *Dec 24, 1991Jan 18, 1994Pymah CorporationSteam sterilization indicator
U.S. Classification374/104
International ClassificationG01K11/06
Cooperative ClassificationG01K11/06
European ClassificationG01K11/06