USRE1473E - Improved low-water detector for steam-boilers - Google Patents

Description

v UNITED STATES PATENT OFFICE.

CHARLES H. BRO\VN, F FITCHBURG, MASSACHUSETTS.

IMPROVED LOW-WATER DETECTOR FOR STEAM-BOILERS.

Specification formingpnrt ot' Letters Patent No. 29,455, dated August-7, 1860; Reissue No. ld 73, dnled i f May 19, 1863.

To all whom it may concern.-

Be it known that I, CHARLES H. BROWN, of Fitchburg, in the county f Worcester and State of Massachusetts, have invented a new and useful Low-Water-Alarm Apparatus for Steam-Boilers; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawing, forming part of Y this specification, said drawing representing a cent-ral and vert-ical section ot' the apparatus.

My invention is a combination consisting not only of an expansion-tube, its valve-seat and valve, and a whistleor its equivalent, but of a mechanism or apparatus so arranged and combined therewith as to produce during expansioukof such tube a counter movement of the valve in a direction opposite to that in which the valve-seat may be moved; the purpose of my invention being that when the tva4 ter in the boiler may fall below a certain level the expansion of the mechanism by the action of the heat of the steam therein shall cause not only the valve to move from its seat, but at the same time the seat to move away from -the valve, thereby, as it were, producing a double action ofthe whistle-valve or its equivalent, and insuring a prompt and certain opening of the valve in order to enable steam to rush through the whistle and sound an alarm; and my invention further consists in the within-described peculiar combination of mechanical devices by which the counter-movement of the valve is effected; and also the peculiar arrangement of thetwo expansion-pipes, their valve, .valvc-seat, and whistle-lever, and the vrod of such lever, and also their arrangement pipe, C, and become like an inverted Siphon.

The said elbow pipe or bend C, which is intended to be placed at some distance above o r away from the boiler, has attached to it a single stand-pipe, D, which opens into it and said lever.

serves to connect it with the boiler. The said pipe Dat its lower end opens into the boiler at a level below that at which it may be deolwhlch is secured to a lixed erosspiece, G,'.

(arranged within and across the bend (3,) by

means of two nuts,l b and c, fitted to a screwthread cut on the rod. @ne of the said nuts is above and the other is below the said crosspiece, the rod being caused to pass through the said cross-piece. The upper part of the said rod is peri'orated to receive the lever H, which operates the valve of the whistle, one end of thesaid lever beingattaehed by apin or hinge-joint, d, to the air-chamber E, or to the upper` part el the pipe B. The other end of such lever extends across the head c ofv the stem e of the whistlevalve j. This valve is of the puppet kind,and closes with an upward movement. it has a spiral spring, g, applied to its stem e, and arranged between the head e' thereof and the top of the whistle, such spring being for the purpose et keeping the valve 'closed when there may' be no pressure oi" steam in the boiler. W hen the pressure in the boiler may be slightly above .that of the atmosphere, it will be suicient to close the valve irrespectiveof the spring.

The slot h, made in the rod F for the lever H, should be deep enough to allow a slight amount of play upward and downward to the Some distance below the said lever there is secured between the pipes A B a fixed guid, to keep the rod F upright.

The operation of the apparatus will be as follows: So long` as the level of the water in the boiler may be above thel lower end of the pipe D and there is any considerable pressure of steam in the boiler, the pipes A and B will be kept tilled with water, which,.bei`ng out of reach of the circulation of the water within the boiler,will not become heated near as hot as the steam within the boiler. While such may he the case, the pipes A and B will not expand sufficiently to open the 'valve f,- but when the water in the boiler may fall-below the mouth of the pipeD the water within` the pipes A B C D, by its gravitation, will fall thereinv and ont of them, and its place will vbe supplied by steam from the steam-space of thc boiler. This steam, being hotter thau'the water, will heat the pipes A B to such a degree as to produce almost instantaneously such an expansionofthem lengthwise that the valve l' will be opened so as to permit the escape of steam to and through the whistle. In this way an alarm will be sounded, the result be# ing effected not only by the upward movement ol the valve-seat a away from the valve, but by the simultaneous downward movement of the valve away from the seat thereof. Such` Therod F, which will never be perceptibly expanded, serves as a support for the fulcrum 'of the lever. As soon as the water may have arisen above the level of the mouth or lowerV end of' the pipe D,` it, by the pressure of the steam, will be again forced up the pipes A and B, in'to which it will enter as fastas the steam therein may be condensed. `The pipes by this water will have their temperature lowered, in consequenceof which they will contract lengthwise, and eect the closing of the valve bythe downward movement of the seat due to the contraction of the pipe A, and by theupward'movement of the valve under the inuence of the pressure of the 'spring g,

Y which will bev permitted by that action which will result tothe leverl by 4the contraction of t-he pipe B.

The lair-chamber E isfor the reception-of the air which shall get into the pipe'B, and which without the air-vessel or a very great-lyextended length of pipe-wouldprevent the steam llng the whole, or-as much of the said pipe as'might be desirable to produce the requisite'degrec of expansion of the pipe. The

' outlet provided bythe' whistle obviates the necessity of an air-chamberon the pipe A', as by. depressing and opening the valve of Vsuch pipe the air will escape therefrom or be driven ,f out by the steam. The play allowed to the lever Hin the slot h will permit the expasion due to the heat of the vwater in the,pipei to take place and not open thevaP,ve,\ f i ',Ihe nuts lb c serv-e. to adj ust the rod so that the valve may open the instant a certain de gree of expansion of the pipes may have been t attained.

From the above it will be seen that I have combined with the expansion-tube A,its'valve seat, and valve, and whistle certain devices' or mechanism, which, by its mode of operation, will produce during expansion of the tube A and the movement of the valveseat consequent thereto, a counter' movement of the valve. that is, a movement of it in an opposite direction. These devices for effecting the said counter movement of the valve are the lever H, the rod F, and the expansion-tube B, connected with the pipe C.

It may be observed that the air-vessel E, in

its application tothe single expansionpipe B, can only discharge its air through the pipe A,- lacewhen the pipes Such discharge taking are filled with the steam and the valve is open. Thus it will be seen that the pipe A not only performs its function of expanding and opening the valve, but another-via, that of aiding the pipe B in the dischargeof its air. The

peculiar combination and arrangement of the air-vessel with the two pipes and the remaiuder of the apparatus is therefore productive.

of important results.

What therefore I claim, and desire to secure by Letters Patent, isj 1. A combination consisting not only of au expansion-tube, its valve-seat and valve, and a whistle or its equivalent, but Va mechanism or apparatus so arranged and combined therewith as to produce, during the expansion ot'. such tube and while the valve-seat is being moved in one direction ,n by such expansion, a'

counter or opposite movement of the valve, substantially as specified.

2. The combinationof the expansion-pipe B, the lever H, and the rod F, in their application to or combination with the tube A, the valveseat, valve, and whistle thereof, as arranged and applied together, substantially asspeeitied. l

3. The arrangementof the pipes Av B, the valve f, the valve-seata, the whistle W, the

lever H, and the rod F, and also their ar-v i rangement and combination with an air-vessel, E, as described. v

CHARLES H. BaowN.

Witnesm; v' Y.

' .A Jas. M. ,'WooDBiJaY, A,

.GEORGE S. JoNEs.

Images