US520875A

US520875A - Pyrometer

Info

Publication number: US520875A
Authority: US
Publication date: 1894-06-05
Anticipated expiration: 1911-06-05

Description

E. BROWN.

(No Model.)

PYROMETER.

Patented June 5, 1894.

lNVENTOR WITNESSES:

in the head of the pyrometer.

the top plate of the frame which carries the UNITED STATES PATENT OFFICE.

EDWARD BROWN, or PHILADELPHIA, PENNSYLVANIA.

PYRO METER.

SPEGIFICATION- forming part of Letters Patent N0. 520,875, dated. June 5, 1894. Application filed September 6, 1 893.", Serial No. 4 4,923- (No model l' Patented in England March 29,1893, No. 8,655.

T0 at? whom it may concern.-

Be it known that I, EDWARD BROWN, a citi -f zen ot: the UnitedjStates, residing at Phila delph1a,inthe county of Philadelphia and State of Pennsylvania, have inventedarnew and. useful Py rometer, of which the following 15 a speeificatiom dated March 29, 1893. 4

perature o'f which -.i s,to.be indicated. I

The ob eot of my invention is, to; censtruct this stem so that it maybe put throughwalle' whichuvary in thickness, or it may be Qim-., mersedin a heated fluid, such as melted tin- H which may varyin depth a foot or more; and

may remain in the said varying medium con--- stantly as a ,fixe'd or stationary pyrometer without changing the accuracy of the indication. 'ThiS desirable feature has heretofore been approximated by me, by makingthe'irrside sliding rod,'which connects the indicatng portion of the stem with the mechanism 1n the head, of the same metal as the-inr closing tube. The result of which is that the pointer indicates higher with a deeper immersion of the stem. The invention herein described consists in the discovery, that as the ratio of expansion of the inside sliding rod is increased above that of the tube inclosing it, the pyrometer becomes more accurate until the excess reaches usually about twenty-five .pe'r cent.,-.a'nd in some pyrometer stems thirty per cent. After this point is ascertained a greater ratio of expansion only deteriorates it again, gradually, as the ratio is increased. Also in the construction of the multiplying gearing within the head of the pyrometer, by which I increase the movement of the pointer and preservea Very free and regular motion to the pointer. I In the accompanying drawings Figure 1 is a vertical section throughthe pyrometerstern. Fig. 2 is an elevation showing the mechanism Fig. 3 shows multiplying lever.

Similar letters referto similar parts. In Fig. 1' is shown the stem. This stem has an exterior --tube D of iron or othermetai, closed at the bottom, upon which rests a bar of plumbago-ware E orsome other material which expands'less per degree of heat than the tube D. Upon this bar E restsa compos- 'ite rod Hconsist-ing oiiiron pieces h and in- Y ltermediate pieces of brassorcopper h screwed Olaim-ghas been included in a patentinjf Great Britain, granted to me, No;' 6,655,, and} tom driven-hard 'uponthe iron pieces. The ro'd'H is steadied centrally within the tube by cililtate therepair of the stem, when the end "is burne'd'ofiibygreat heatgl makethe end of vthick cast iron andscrew it by an inside screw into. the end of thetubeD. By this improvement the part'of the stem subjected to the i I h I buttons g driven or'screwed upon it. f To fa I My nvention'relates to'the construction of. fixed or stationarypy-rometers which have a long stempro ectinginto a medium, the-ternat K to the tube D. A plug K is screwed destructive action of heat is easily renewed without the loss of the remaining portion.

his a sliding collar upon the stem.

, Ais a cast iron, box forming the pyrometer head; Thishead is screwed to the stem by' the co'upling M.

.0 is the pointer, 13 the dial. In the case or head A is seen the multiply-- This consists of a frame, N,secured by screws n to the case. f

m is a differential adjusting screw. One

end of it passes through the case, the other i through the frame N. The screws it pass through elongated slots in the frame N, and by turning the screw n a small vertical movement is-given' to the frame N. Within the 'frame N is mounted the toothed quadrant P on a pivot, 19. The spring-S is hooked to an arm of the quadrant P at one end, and to the case A at the other end. A small pinion n, which carries the pointer 0, gears into the quadrant. At one end of the quadrant P is hinged the adjusting-armW by means of the screw-pin 19 The other end carries a pin, 17 .by which it is jointed to the'connecting-link 7". The arm W is also slot-ted near to the pin 10*, and a set-screw, p, passes through the said slot into the quadrant P and serves to fasten the arm W rigidly to the quadrantwhenthepin p is at the exact radius required for each particular pyrometer. The arm V. isso adjusted that the pyrometer indicates correctly when all the parts of the stem are evenly heated, as consequent upon its permanent immersion in the medium to be indicated. The other end ing mechanism which-actuates thepointer O.

tom of the tube K.

A pyrometer stem is subject to a variety of uses. Suppose it to be used in meltedtin up to the point K and it is tested and adjusted accurate for that immersion, it will, as ordinarily constructed, with the rod H and tube D of the same material, indicate somewhat higher when immersed up to the collar L. By making the inside rod II of a metal which expands about twenty-five per cent. more per degree of heat than the tube D,the said proportion varying slightly more or less 1 with the diameterof therod and tube, I overcome this error. Thisproportion may be adj usted more accurately by changingthelcngth of the expanding pieces k until the pointer gives an accurate indication, whatever may be the depth of immersion of the stem.

I claim- 1. In apyrometer the combination of mech anism in the head, which is adjusted to indicate' accurately when the stem of the pyrometer is permanently fixed in the heated medium, with an outside expansion tube, an inside bar E, and a sliding rod IL, which rod II as herein described.

isproportioned in its expansion per degree of heat in excess of that of the tube inclosing it, up to the vicinity of twenty-five per cent. greater; to maintain accuracy of indication under varying depths of immersion as herein described.

2. In a pyrometer stem, the combination of the expansion tube I) and the rod I'I made of pieces h, and more expanding pieces h by which the total expansion of the rod H is adjusted as and for the purpose herein described.

3. In a pyrometer stem, the combination of the outside tube D, the separable thick expansion tube K, screw threaded to the tube D, the interior bar E, the composite sliding rod 4:. In a pyrometer or gage head, mechanism in combination as followsz-the frame N, pin- .ion n, quadrant P, adjusting arm W, link 0" lever B, connecting link r", substantially as described for multiplying the motion of the link 7' upon the pointer C. l

5. In a pyrometeror gage head the following combination of parts: the frame N the top plate a bent over as shown to form a support for pivot for the lever B, pinion or, quadrant P, adjusting arm VS, link r, connecting link T for communicating the motion of the stem to the pointer.

EDW. BROWN.

\Vitnesses:

JOHN F. GRANT, LEWIS M. KENSIL.