US1824902A - Valve - Google Patents

Description

P. Wl KNAUF Sept. 29, 1931.

VALVE Filed Jan. y10, 1930 ATTO/P/VEK Patented Sept. 29, 1931 UNITEDTSTTATES rAULYW. KNAUF, or cYnwYn. rENnsfrnvANrA, nssrGNoR To sentirmi: hun xoERrrNo t.. COMPANY, or Pinamar:prima, PENNSYLVANIA.; CORPORATION 'oFrnNNsYL- Valium.Y s.

Application' mea January 1o, 193e. semrm. 419,790.

My invention relates to valves of the type which perhaps may be characterized as vheavy duty valves. In valves of this characterv it is the usual practice to employ pilot valves in 5 association-with the main valves to facilitate the opening'of the latter from closed positlon.

In the use of -valve structures embodying main and pilot valves itis necessary'that the' latter have a certain amount 'offplay' and itl 10 frequently happens that theV main valvesl chatterwwhen close to their seats vduring y1f; vide a construction having ymeans wherebychattering or vibrating movements of the main valve relative to the pilot valve shall be prevented.

` l VIt also is an object of my invention lto pro-- '20 vide a construction wherein the pressure'ezz-l erted by the steam withinthe valve struc# ture tending to cause longitudinal movementl of the main valve withy reference to the ypilotl valve, to which the said main valve islcon' nected in one direction is counterbalanced' by an equal pressureV in the opposite ldirection whereby the pilot is held open'untilseated by final downward movementapplied* to f its stem.

Without further amplification or statement of the objects of the invention -I shall now proceed with "Y the detailed Adescription thereof wherein additional objectsiand ad-I vantages will be pointed out or'else will be come apparent. In order that the invention may -be readily understood and its practical advantages fully appreciated reference lshould be' had to the accompanying drawing wherein' I have illustrated a longitudinal sectional yview of1 a valve construction provided with the novel means of my invention.

In the drawing I have shown at `1 a valve casing comprising an inlet 2 and an' outlet`3, the inlet and outlet being oifset withrelation to each other as shown. The inlet hasconnection with an upper chamber ofthe' valve casing while the outlet has connection with a lower chamber, the two chambers -being separated by a partition wall 4 having an openpresence of the packing surrounding the tail oFEI'c-E? ing k:5 therethrough which lis adapted to be opened and'closed byv means of a valve 6. The upper side' of the partition wall'4 is'provided with ansrannular member 7 the upper-'inner edge of which constitutes 'the seat 8 for the-5"5` saidvalve. The upperchamberof the valve casing is closed by means of a cover or closing plate 10, the said cover plates kbeing secured to thejlopenupper edge .of the casing 1 by A means of fastening bolts 11. These bolts 1v1 de" also operateto fasten the tubular pedestaly 12in place upon ythe'casing, the said pedestalv being provided with aflange or foot portion 13 for that purpose. Suchk flange orfoot portion rests upon the upper side of the outer 665i edge portion of the cover plate 10.v f The bottom end o the lower'chamber of the casing is closed by alcover 14 which is secured by means of fastening bolts 15. Thelower part of the lower chamber ofthe casing is provided with a cylinder 16 which. is secured and held in place by means ofthe cover: plate 14 which contacts :with the lower end'of saidl cylinder. The 'said Acylinderis o en at both ends. The v n hollowspool or stem 1 which projects down-v 75: wardly'Z from the valve or longitudinallyofthe'valve casing is providedwithl a headj or piston F2O vat its lower end :which fits. closely within the cylinder 16. f The'sp'oolisprovided in the opening through thepis'ton at its lower c* end with'a'crosspiece21 to which-is secured a tail piece 22 whichy Iprojects outwardly through an opening 23 providedin the cover plate 14 and into a tubular extensiony 24 the inner end yof-whichV terminates with a glandfportion 25 which engages and is adapted to hold a packing 26 within a vchamber provided by a llangeportion 27 K which projects from the outer side ofthe cover plate 14. The

rod or piece 22 is for the purpose of rendering the opening 23'steam-tight. The -lower .end of` the tubular extension 24 is provided with an openingfrom which any liquid which may collectgtherein may escape. The presence of said opening also exposes the tail rodor piece 22 to the' atmosphere.V .i

p YThe valve 6 Vis provided with an upwardly extending hollow projecting portion 30 the vupper endetV whichissli'ghtly enlargd'and l-100 f c losedA by means of a'pilot valve 34 whichis connected with and constitutes a head upon the inner lower end of the rod 35, the saidv rod constituting a stem for *the said pilot valve.' For connecting the pilot`valve-34 and its stem1 35V with the valve G ,and its spool-17 Ihave provided a disc :36` which 'is .secured'in the` upper end of the hollow portiorr() byY fasteningdevices indicated atf37;z The central portion of the ydisc 36 is provided with anelongated hub 38 having a. central'yopening therethrough'through which the `rod or pilot valve stem35 extends. 'The lower or inner end of the `hub 38 -is located a short distancefrom the upper or'jo'uterend ofv the pilot 'valve34 so thatthe'said pilot valve is permitted-toA move throughs-av short distanceI between lits seat upon the vtop4 of the valve 6 andthe innerz or lower end of the said hub. The said rod ori pilot valve sternl35 also extends through an 0pening140`in the cover plate 10.v .The outerY end of said opening isienlargd'as indicated' and is surroundedby'a tubular-flange" portion 41.- nThe space within the-enlarged porftion of said opening surrunding-the rod 35 is filled with packing material' 42 which is adapted tobe compressed and retained in position byagland member l43 which is held in position by' fasteningandtightening screw bolts 44".v `rPhe rodvor'stem `35'is movable through the1open`ing'40fand is provided; at a point withinthe pedestal l2 with a crossw'ise extending'inemherll whicheis-adapt'e'd to engageguides-46 in` opposed vrelation i tol each i otherupon'thefinnerside ofthe hollowy pedestal'12.y The-upper'end portion'of the roeier stem o 35 is screw-threaded as shown at r47 and is in engagement' with the screw-threaded portion 48 at the upper end of an elongatednut 49 which -is adapted tobe rotated 'by means of Ta hand wheelfO. Rotation of the said nut maybe eiec'ted'by other. means which may bepower actuated.- .The lower Vendof the nutprojects through aliopeningxl provided in afplate 52 which closes*j the upper end of the" pedestal 12,'k the said plate being secured to the' pedestal by?y fasteningvv screw bolts 53 The nut 49-is provided .with-aflateral annular 'flange or projection-55 intermediatev its' endsthe lower sideA of which rests upon Ythe upperus'ide ofV a ballbearing'assembly 57 which is supported upon the upper side of the coverfplat'e'atthe bottom of a chamber provided' by the upwardly :extending tubular projection -585 -S'aid' projection is Thev valve. is provided with a cent-ral. o ening'33'rwhichis ada'pte'dto be opened and j meansof fastening screw bolts 64. The upper or youterside ofthe ballbearing ring 6l is pr'actically*flush with 'the`upper edge of the "tubular projectionA 58 i The diameters of the rod or pilot valve stem A3`and the tail rod or piece 22 are the same or practically so. Inmother words, their diameters should be y'as nearly the same as is commercially'practical. a K

When it isdesired to open the valve 6 the hand Wheel l50er other means which may be poweraetuated, -as previously stated, is rotated'to turn the'nut 49 in `a direction to cause outward Imovement first-:of the rod35 andthe pilot valve 34.4 connected *Kt-herewith. 'Opening; movement ofthel pilot valve 34 is resisted by the pressure ofthe steam-,upon the area ofthe outer side thereof which surrounds thestern;n The area of theannular space upon the upper1 or( outer side of ltherpilotv valve which surrounds the rodor stem 35 is quitersmall as compared with the imilar area Vofthe valve 6. It ffollows, therefore, that while arelatiyelysmall force only is necessaryatoi-imp'art initial opening movement to the pilot valve 34 a relatively great or large force would begrequired to impart initial movementg to `the-,valve 6. The pilot valve.- having :been once opened, however, steam flows,through-Athe,'opening` 33V and through the tubular. valve spool Hand-thence to the under side .-offthe latter'and the head thereon.4 VThesteam thus 'being present both abovevand below the-valvethe latter may nowy bev moved-Tinta.,openfposition without the necessity of. overcoming any lpressure Ol force other than that due to gravity and to frictionfhetween moving parts. i

j Heretofore Y there has been difficulty owing to the j-chattering of the main valve between its-seat 2and-the pilot vlave. By providing the tai-l piece-2,2 whi'ch5as well as the'rod 35, is exposed to the atmosphere vsuch chatteringuis prevented. 1' lThepressure exerted by thefsteamor other 'fluid pressure after itentjers the 'Spool'l7 through the opening 33 is exerted equally lagainst-theV rod 35 andthe tailrod orpiece 22.v EIt follows, therefore, that :when they-pilot valve and lmain valve are moving from an open position of the main valve (the pilot` valve being likewise open) the'said pilot and main valves move together withthepilot--valve remaining open' until the main valvej'oontacts, with -its' seat at 8 whereupon. the lpilotvalve continues-its move- Ament V.until it isseated1 upon fthe main valve.

This-iinalclosing movement ofthe pilot valve of the luid within the vilve casing against such movement is such that less effort is required to be applied to the wheel 50` (or otherA operating means) than is required to unseat the pilot valve when moving the same from closed to open position.

Although performing no function insofar as the present invention is concerned itmay be noted that I have provided a screen structure which surrounds the portion of the valve structure which is located in the inlet portion of the valve casing. i

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

l. A valve structure of the character described comprising a valve casing, a movable valve member located in said casing for closing an opening therethrough, said valve member having a hollow guiding stem yand also having an opening therethrough in communication with the opening-through the said guiding stem, a valve for closing said opening, said valve having a stem which is exposed to the atmosphere, and a tail rod having connection with the said hollow stem and being exposed to the atmosphere, the diameters of the said tail rod and the stem for the second named valve being approximately equal. Y

2. A valve structure ofthe character described comprising a valve casing having an opening therethrough, a'movable valve for opening and closing said-opening, said valve having a hollow stem projecting therefrom,

the opening through said stemvbeing in communication with the opening through the said guiding stem a pilot valve for closing the opening through said movable valve, said pilot valve having a stem exposed to the atmosphere, means for limiting the movement of said pilot valve, and a tail rod connected to the hollow stem of the lirstfnamed valve and exposed to the atmosphere, the said tail rod and the said pilot' valve stem being of substantially-the same area in cross section.

phere and the cross sectional areas of the said tail rod and the said pilot valve stem being approximately equal.

` 4. A valve structure of the character described comprising'a valve casing having an opening therethrough, a movable valve member for opening and closing said opening, said valve member being provided with a downwardly extending hollow guiding stem, an upwardly extending guiding portion and a relatively small opening therethrough in communication with the opening through the said stem, a pilot valve for opening and closing said opening, said pilot valve having a stem extending upwardly in a direction opposite that of the said hollow guiding stem of the first named valve, means mounted upon the upwardly extending portion of the said rst named valve for guiding the pilot valve stem and for -limiting the movements of the said pilot valve, the'said pilot valve stem projecting from the said casing and being exposed to the atmosphere, and a tail rod connected to and extending from the lower end of the said hollow guiding stem of the first namedvalve and projecting from the said casing and being exposed to the atmosphere, the cross sectional areas of the said pilot-valve stem ,and the said tail rod being approximately equal.

my invention I havey hereunto signed my name this 9th day of January, A. D., 1930. l

PAUL W. KNAUF.

3. A valve structure of the character de-k y scribed comprising a valve casing having an opening therethrough, a movable valve member for opening and closing the said opening, said movable valve member having a hollow stem projecting therefrom and also having j a relatively small opening located centrally thereof in communication ywith the opening through the said steam, a pilot valve forclosing said relatively small opening, said pilot valve having a stem which projects therefrom and which is exposed to lthe atmosphere,

means `for guiding the movements of said stem, and a tail rod having connection with the said hollow stem of the irst named valve, the said tail rod being exposed to the atmos- 95 1n testimony that I claim the foregoing as v

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