US1857514A - Locomotive safety valve - Google Patents

Description

y B J MORRISON LOCOMOTIVE SAFETY, VALVE Filed Dec. 17, 1929 Patented May 10, 1932 TES ' UNITED STA BARTHOLOMEW J. MORRISON, OF BALTIMORE,

PATEN MARYLAND, AssIeNoit- Torn- GOALE OF MARYLAND LOCOMOTIVE sArE'r VALVE Application filed December 17,- 1929. SerialxNo. 414,65;

In accordance with the vpresent existing practice all or nearly all locomotive safety valves are of the type known as feather valves having a cylindrical guide at the top and 5, bottom. In such valves the feather or guide at the top forms a cup'xwhich'contains the lower spring button and alarge part of the lower portion of the spring. 4 The spring is I seated at its lower end on the button which is in turn positioned by means of a socket in' the bottom of the cup which is engage by a central projection on the button upon which it is free to rock'. The water which works upwardly from the valve opening between the feather and the external guiding member of the valve casing comesin contact notonly with the bottom of the spring within the cup, but by splashing keeps the entire spring moistened. The water which it'is necessaryto use in steam plants in various parts of the country has a strong. corrosive elfect, particularly with the various boiler compounds with which it is treated, and corrosion of the springs in many localities isso rapid that they last but a few months, when it becomes necessary to lay up the locomotive for repairs to the safety valve.

A further difficulty is due to the accumulation of sediment in the cup'at the top of the valve. This-sediment tends to fill the cup and clog the lower portion of the spring ren-- dering it practically solid so that the effective length of the spring is reduced, with a corresponding reduction in the opening of a the valve, reducing its capacity and regulating effect and correspondingly increasing the time required to exhaust sufficient steam from the boiler to give the required degree of regulation. This loss of capacity has various harmful effects too numerous to mention.

The object of the invention is to overcome this difiiculty by protecting the spring from the action of the water and other corrosive agencies carried thereby and to prevent the accumulation or deposit of sediment around the spring, particularly the lower portion, as aboveoutlined, with consequent interference with and reduction of. the resiliency of the 7 spring and loss of capacity of the valve" To this endthe spring has been completely enclosed and access .o fzthewater thereto prevented the casing may be. variously formed, constructed and supported. V In the preferred form the lower springbutton has-been de-j veloped and extended to i provide such a spring casing which ton and slides up and down in a spring chamber corresponding to the spring chain berformerly.provided-in such safety valve casings. The sliding ofthe spring casingin the spring chamber provides for the normal motion of the valvejin openingandrthe corref spondingmotion of the lower button;

isintegral with the buti In the accompanying drawings-I have il-:

lustrated a locomotive 'safetyvalve embody ing theinventive featuresiinythe preferred form. In the drawings z, .e Figure *1 -IlSf 3;-VItlCavl: central section. through the valve --casing,and valve; spring casingand button; v g j 1 "Figure 2 is a horizontal-section" on the line 2-7-2 of Figure 1.) f f Referring to-"the drawings -by"'numerals,

each of which is usedto'indicate thesame -or similar. parts in the "different figures, the il-,

lustration comprises a locomotive fsafety,

valve casing '1, closely resembling the type in general use having a dome 2,jspring-cham-f ber 3, upper valve guideI4-,lower valveguide 5,valve seat 6, valve-7,; and an upper, cylindrical feather or'gcuplike guiding member, 8 and lowerguidingmem-beri), i The disclosure also includes valve spring 10,;the upper spring button 11, which serves as a top abutment for the spring, the same being positionedfromabove by-the adjust in g screw 12 and the lower bu tton 14 by which thezjspring pressure; is transmitted to the valve7., a The top guiding member or featherj8 of "the valve is shown infthe formpof an v projecting cylindricalfwall which in accord ance with the usual practice,jhas anfoutwardl ly disposed guiding surfacercooperatingjwith the upper valve. guide This gives the t'op of the valve a cuplike formation on tllQFbOttom of which thelower'springbutton llyis" 1' supported in a central positioning-socket lfi action of the water and other corrosive elements contalned therein and from the accum'ulation of sediment, th Valvev Spring 'is enclosed in a spring casing 20 which permits of considerable variety in form and arrangement. In the form of the invention shown, this consists of a vertical cylindrical wall extending upwardly from the outer peripheral top edge of the button nearly tothe top of the spring chamber 3 and sufficiently spaced therefrom to provide for-"the upward motion of the valve 7 in opening. This casing 20 has a free slidingfit in the chamber 3, there being clearance enough to prevent clogging and binding of the casing in the operation of the valve. To provide for the release of any water which may be blown upwardly between the valve guide a and the feather or valve guiding member 8, and which tends to work-upwardly between the inner wall of the valve chamber 3 and the valve casing 20, thewalls of the chamber are apertured radially at 21 and the outer wall of theguide at the top is grooved at 22 to impound the water and lead it to thereleasing apertures 21. v

v In the operation of the safety valve when the boiler pressure is sufiicientto raise the o andthrough valve by causing the pressure 'on the lower surface of the valve to compress slightly the spring 10, the steam whichis to be released for purposes of regulation passes between the seat 6 and the seating surface13 of the valve the huddling chamber 23 of the Atthis point the escaping steam usual type.

the downwardly disposed pereacts against ripheral surfaces 23 of, the valve, tending to 7 hold the valve open until regulationha's been fully accomplished.

From this point the steam moves upwardly through the steam passage 24 tothe dome 2 whence it is released tothe atmosphere throughthe perforations 25'. When the pressure exerted upon the lower surface of the valve drops through the 7 low point of regulation, the valve' is closed by the spring 10 and thefiowof steam stops.

This motion of the valve in opening and closing. against and'in response tovthe pressure of the spring 10Vresults in a corresponding'motion of the lower button 14: and the casing 20 the invention is integral therewith. The casing thus caused to slide back and forth in the spring chamber 3, throwing the groove 22 into and out of registration'with the apertures 21 whereby any water which works between the casing and the chamber walls having been accumulated in the groove 22 is released .by wayof the aperture 21'. W

The spring is thus completely'fprotected' from the actionjof the water and other cor detail a safety valve embodying the r in the claim.

rosive elements and from the accumulation of scale and other sediment about the spring whereby the lower portion of such springs has been clogged, and the length of the effective resilient portion reduced.

The protection of the spring from the water and other corrosive agencies greatly increases the life of the spring corresponding ly increasing the periods between replacements and reducing the number of such replacements and the loss of service of'the lo-' comotive on account of repairs to the safety valve.

The elimination of clogging of the portion of the spring in the cup tends to keep the operations, i. e., the valve opening and capacity of the valve constant, obviating the necessity for frequent regulation or cleaning, etc., and reducing the number of periods of loss of service of the locomotive for adjustment or repairs. a

I have-thus described specifically and in features of my invention in the preferred form in or-f der that the manner of constructing, operating and using the same andthe manner of applying the'invention may be fully understood, however, the specific terms herein are used descriptively rather than in a limiting sense, the scope of the invention being defined hat I claim as.new and desire to secure by Letters Patent is:

The combination in a locomotivesafety valve of a valve member'ha-ving a top guide formingia cup, a valve spring, a top abutment for the valve spring, ment for the spring in the form of a spring button bearing on the valve near thecent'er of the cup, said spring button having upright cylindrical walls forming a spring casing, enclosing and protecting the spring, the valve structure.comprising a correspondingly cy lindrical spring chamber in which said cas ing slides freely, said chamber having releaseiopenings near the top and the casing 166 a bottom abuthaving corresponding grooves to impound,

which, in the preferred form of me at Baltimore, Maryland,this

' iis

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