US1752321A - Drifting valve - Google Patents

Description

April 1930- D, T. WILLIAMS 1,752,321

DRIFTING VALVE Filed Dec, 51, 1925 2 Sheets-Sheet 1 1 y 3 6" g G L .L'=" J WITNESS WQ DawdLIWnhams I I v ATTORNEY D. T. WILLIAMS DRIFTING VALVE April 1, 1930.

, 1925 2 Sheets-Sheet 2 Filed Dec. 31

ATTORNEY Patented Apr. 1, 1930 UNITED STATES DAVID T. WILLIAMS, OF EATER/SON, NEW JERSEY DRIFTING VALVE" Application filed December a1, 1925'; Serial No. 78,567. i

' This invention relatesto automatic means whereby, when the driving steam is cut E from alocomotive engine, fluid, as boiler steam, is" admitted to the engine, and when the drivingsteam is allowed to flow to the engine'the flow of such fluid is checked, so

that under the first of these conditions the known disadvantageous results ofthe piston continuing to reciprocate in vacuo inithe en- '10 gine cylinder will be avoided. The object is to -provide improved means of this class, or what is known as an automatic drifting valve, which shall embody 'all ofthe following advantageous features, to wit, efliciency 1 under allconditions, simplicity of construc-' tion, andreliability not only in} respect to the performance of its principal function but to the-end that its incorporation in the equipment of a locomotive shall not introduce any 2 possible element of danger I have fully illustrated my invention in the accompanying drawings,-in which Fig. 1- is aside View of alocomotive embodying the" improved drifting valve Fig. 2 is a fragmentary rear elevation of th'e'boiler', steam turret and one of the-steam pipes; and g Figs-3 and 4 are a vertical'c'entral sectional view and an, end view of the device. The locomotive has an engine of usual type,

1' being the cylinder and 2'the steam-chest;

3 is" the main" steam pipe for super heated steam leading to the steam-chest, and 4 is" a steam turret communicating with the" boiler 5 andconveniently placed" as usual in the drivers cab. i

I The drifting valve is indicated generally in- Fig. 1 by the character 6: The pipe through which control of the moving'part of this driftingvalve is eifected from the steam-chest (or'rather all that space, which I termthe working space, which is subject to the suction-action of the piston in said cylinder when the locomotive is drifting with thedriving steam cut off) is indicated at 7 it may have a shut-offcock 7 The passage to'be'controlled (i. e., forfiuid, assaturated steam, which is to beadmitted to the locomotive cylinder when thelocomotive is driftingwith the driving steanrcutofi) is affordthe source 4,- which communicates with the" ed by the pipe8, acylinder (tobe described-) of the drifting valve 6, and a-pipe 9; pipe 8 leads fromthe turret 4 to the drifting valve and maycontain a reducing valve 8 (Fig.2),

and pipe 9 leads from the drifting! valve to 5 any part of the mentioned working space, as the main' steam pipe 3, and it may if desired contain a check-valve 9 the detail of which is not shown and which it is not material to describe except to say that it closestoward the driftingvalve' It is neither necessary nor desirable,of course, that th'e steam'pass ing to the locomotive'cylinder via 8-13''9' shouldhave a pressure as great as that at boiler; hence the reducing valve 8 is pro vid'edz The casing or fixed part of the drifting valve includes a' hollow structure 10 having a base 11 and forming two cylinders 12 an'd 13 axially" a lined with and open toward each other,-the' former (or what-I term the major cylinder) being ofappreci'ably greater crosssectional areathanthe latter (0rminor) cylinder; and heads'l t and 1-5bolted' to the outer ends of cylinders 1 2- and 13, there being a" space or chamber- 12* between-the cylinders. The moving member of the deviceincl-udes' a major pisto'n-16-fitting cylin'der'lflganaxial stem 17- suitably secured to said"-pistolr,- and an element here formed in two parts 18 and- 19 with a'spa'ce or deep groove 'l e between them, they being suitably secured to the stern; and part 18 forminga valve to control the aforementioned passage." The or cylin der piston iii-effect form a'moto'r forsueh valve: VV'heir' the locomotive engine is working the pressure in its mentioned working space actsthrough a port7 with wh-ic'h-pipe' 7 communicates to hold themoving member of the drifting valve with piston 16 against a stop fiange l6 'an'd hence th'e valve'i r closing relation to the passage; when the docomotive'engineis drifting, asthe result of the suction developed in said-working space, said moving member is shifted to the left,-so that valve 18' uncovers the passage from 8 0 9 via space 19 and said passage is open and boiler steam flows tos'aid working s ace.

Piston 16 ha's a port 20 c0nnectingchamber as suction is created (on drifting) in the working space of the engine, with consequent reduction of pressure at the left of piston-16,

and since the pressure area of piston 16 ex:

ceeds that of the valve portion of element 1819, the pressure in chamber l2 is effective to and does produce a ce tain and quick movement of the said moving member to open "the communication from 8 to 9. There is preferably a vent 23 connecting the outer end of cylinder 13 with the atmosphere; it maybe suitably restricted so that the movement ofthe movable memberof the device in each'direction will be cushioned. A standardizing of -the resistance opposed to the right-hand or valve-closing movement of the moving member is obtained by providing a vent 24: which is closed by piston 16 on such movement but is opened to the atmosphere when said member moves to the left; this vent, and a port 25 in stop-flangel6e also permit draining chamber 12 of any condensation.t

Valve 18 is cup-shaped, with its open side toward part 19, and its cylindrical wall has radial ports 26 therethroughcommunicating with an exterior circumferential groove 27 whichwhen the valve is closed registers with a vent 28 leading to the atmosphere.

The action of the device is both quick and certain, not only in the movement to close the passage afforded by 813 9 but in the movement to open the same, due to the trapping of steam'from the working space of the engine in the chamber 12 and to the superior area of piston 16 over that ofthe valve portion of the element '1819 taken with the existence at this time of suction at the left side of the piston.

back through pipe 7 to cylinder space 12 would act to move said member to close off the passagebefore the pressure would build up in theworking space -of the engine sufiicient to start the same. There will be a venting at 28 of steam entering the casing from said passageif, the moving member being in closed position, there is a leaky condition of the part 18, for instance, if thisis due to longitudinal scoring of said part-so that the leakclosed position the pressure at the right of part 18 is not a resisting force because parts 1 9-1S then trap this pressure.

serve to vent this pressure at the end of the closing movement ofsaid member.

Any condensation which at times might form in pipe 8 when the valve is closed may find escape into space 19. by port 29, this port being small enough so that the escape of steam therethrough and to space 19 and thence via 19 18 -262728 to the at mosphere would be negligible. r v

Having thus fully described my invention Regardless I of the pressure of the part 19, 18 262728 what I claim and desire to secure by Letters j Patent is: V

1. A drifting valve device for locomotive engines incrudiug a cylinder having an eduction port in its cylindricalwallforming with said cylinder a part of a passage for conducting fluid to the working space of the engine while the locomotive is drifting and a valve movable lengthwise of andin the cylinder to close ofi said passage, said-device having means for venting from the cylinder fluid entering the latter when they valve is closed including a groove surrounding the valve at one side ofsaid eduction port and:

a passage extending from said groove to the end of thevalve-at'the other side of said port. 7

2. Ina drifting valve device for locomotive engines, the combination of a passaged structure for conducting steam tothe work ing space of the engine includinga cylinder, and a valve movable in the cylinder to close 0E from the latter the part of the passage leading thereto, said device having means, closed by the valve when the latter is open and extending through the valve, f ,r venting to the atmosphere when the valve is closed condensation then accumulating in said part of the passage. 7

3. In an apparatus of the class described, the combination of a casing having alined major and minor cylinders and achamber intervening between them and communicating with'the major cylinder, the minor cyl-' inder having an inlet adapted to be connected with a steam source and an outlet adapted to be connected with a locomotive steam chest, a piston in the major cylinder, a valve in the minor cylinder to control steamfiow through the latter from the inlet to the outlet, said piston and valve being movable longitudinally of the cylindersas a unit andthe major cylinder having its outer end closed and also having an inlet to admit fluid fromthe steam chest to the space between said end and the piston whereby to move the latter and hence the valve in one direction, a check-valve means to permit a part of the fluid entering said space from the steam chest to pass the piston and enter and become trapped in said chamber, and means to vent said chamber on exhaust of the fluid from said space and consequent return movement of said piston and valve. V

In testimony whereof I aflix my signature.

DAVID T. WILLIAMS.

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