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US903530A - Automatic cylinder relief and vacuum valve. - Google Patents

Automatic cylinder relief and vacuum valve. Download PDF

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US903530A
US903530A US43308508A US1908433085A US903530A US 903530 A US903530 A US 903530A US 43308508 A US43308508 A US 43308508A US 1908433085 A US1908433085 A US 1908433085A US 903530 A US903530 A US 903530A
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valve
cylinder
piston
steam
engine
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Byrd Oliver Yearwood
Robert Cuttler Pattison
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B20/00Safety arrangements for fluid actuator systems; Applications of safety devices in fluid actuator systems; Emergency measures for fluid actuator systems
    • F15B20/004Fluid pressure supply failure

Definitions

  • the interior ofthe'biise orside und produce undue or excess pressure support 7 communicates with the inteiio'r'oil on the 4other eide, but the two ends of the the cylinder 1 through us'uitable port :12. cylinder willbe connected together or to the ,Projecting from one Side of-fthe cylinder. l external atmosphere so that; the pressure is near the end renxote from the neek iS a relieved and (he tendrjiuey to forni n. vacuum boss? l?) intern-.illy threaded for the reception' 2.3 is: destroyed.
  • nl u pipe 14- und coninnlnicuting with the rlhe invention cr'nuprises u vulve structure interior of the cylinder .l through n port 15'. ilrwhieh springs nre omitted Hinf'e they are l The enti of' the cylinder l remote from the liable to become corrmiled or get out of order.
  • neek I5 is rlosed by :i hend lt securely bolted und the vulve is so omistr'ucted that the ini- .in pince so :is to be steunt tightwit'h the cortial pressure of St cuni in the .Qteurn chest4 will renfooi'ldii'lgr endof the cylinder ltior'rned Seur. the valve und hold it in its sentl while on the inner face ofthe head 16 is u central differential, preszure between the steam chest; projertiing member 17 entering.
  • Fig-3 4 is a side elevubeer against the inner .talee of the piston 1, tion ot un engirur. cylinder and adjacent where it mores upon the outer for-e of said parte ⁇ Showing; t.wo connected vulves at the projection 17. '1y-he pir-:torY 18 ut "the end re- Lwo ends of the cylinder.
  • Fig. 4 is an end .mote from the heur] 16 is formed with' u -levatzion of the structure shown in Rig. 3. vulve sent 25 shaped to engage the sent 6 Fig. 5 4is un end elevation of n modified form when the piston is moved toward the rightl :3o of. the invention.
  • FIG. 6 is n front elevation ms viewed in Fig.' 1.
  • the chamber 19 is oil.
  • t e locomotivev cylinder will force the valve open and-the vacuum created in the steam connection will vhold the valve open even against a greater vacuum in the locomotive cylinder, owing to the difference in area of t e two end walls ofthe iston or valve 18.
  • the area of t e wall' 27 is from en per cent. to twenty per cent. greater, than the effective areav ofthe wall 28.
  • the valve is applied as closely as possible to the steam ports so as to avoid a wasteful increase in clearance which is a natural defect in the piston valve en ine.
  • valve is o )e1-ated entirely without having done any useful work.
  • the two valves are connected together by a pipe sutliciently large to carry the hot gases and air'from one end of the cylinder to the other, and the reverse when thL ⁇ two valves remain open andthe engine is drifting.
  • the pipe indicated. in the drawinfr by the reference numeral 27 and at eaci cndf enters the corresponding neck 3 of a valve casing 1.
  • the neck 3 where entered by th pipe 27 is suitably counterbored to receive a packing gland 28 and packing 29, while a flanged collar 30 is screwed upon the threaded portion 4 of the neck 3 and serves to hold the gland 28 and packing 29 in place.
  • the pipe 27 may be omitted and the ends of the neck 3 remote from 4the casing l may be freely o ened to the atmosphere. ⁇ Under these com itions the air is simplydrawn into thc engine cylinder and again fori-cd out on tluI return stroke of the piston.l thereby preventing vthe vacuum or excessive back pressure in the locomotive cylinder, but the presence of the pipe 27 by preventing the initial condensation in the cylindersiF-f the cylinder walls remain warm when the engine 1s drifting, results in a further saving of fuel.
  • valve consists of practically three parts, namely, the valve prop cr, the valve casing, the valve head, and all springs and other' partsliable to corrosion or to get out of order nre omitted, whi le 'the bythe presence or absence Ao steam presure. 4 y
  • the valve meets all the requirements of the piston valve and compound locomotive.
  • the valve particularly adapted to coin pound engines since it readily adapts itselt to the varying pressure that the high and low pressure cylinders are subjected to.
  • the principles upon which the relief valve are constructed are applicable to other connections than the one shown in the drawing and it is to be understood that theinvention is not limited to the exact construction and location of the parts illustrated and described, but these parts may bc modified as the necessities of service may demand.
  • the valve is, also, applicable to the walls of the cylinder by boring a chamber in the walls of t-he cylinder connecting both live steam portsi rl ⁇ he chamber or port will perform the same function as the connectii'ig pipe Q7 between the valves and will, also, form the body oi' cage for the valve. This arrangement is shown in Figs. 5 and G, where the connecting port is indicated at. 31, and the live steam ports indicated at communieating at each end with the connecting port. 31.
  • the walls of the cylinder are counter-bored, as -shown at 33, to receive a cylinder 34,-housing the piston 18, while the ends of the connectingare formed into af valve seat 6 receiving the valve '2G on the end of the piston 1S.
  • the outer end of the cylinder 3l is carried to a point flush withthe end of the locomotive cylinder body and a head 41G is there applied with the. central projecting member 17, as in the structure shown in Fig. 1.
  • the cylinder 34 is provided with a porty 35 corre. spending to the port 15 ofthe struct-ure of. Fig. ,1, and thisiportis in coinmnx'iication through a pipe 14 with the live steam side of the steam chest.
  • a relief-valvel mechanism ⁇ for engine cylinders comprising a suitable differential valve member at each end of the cylinder and in communication with the correspond 'port or passage 31 ing end of the interior thereof, a means of eomn'iunicaziion between the. steam chestand 'all each valve on i l i l the side thereof remote from, its seat, and means of t'ifcc connnunii-ation between the valves at their seat ends.
  • An cabine tirada-r having formed in. its walls 4at cach end a receptacle having a 'valve seat, said receptacle communicating near one end with the interior o the cylinder :i the respective end of the latter, and said cylinder also being formed 'with a chan nel connectin' the two receptacles at the valve seat endl's, and a valve' in each receptacle, said, receptacles having means of coinnnniication between the ends thereof remote from the valve seats and the steam chest o the cylinder.
  • a relief valve for' engine cylinders comprising an annular 'open ended piston.
  • valve member and a. receptacle therefor having al valve seat near oneend for the valve and a head at the other end provided with a central, inward projection, entering the annular piston, and along which the piston or valve is movable, the said receptacle also having' means of communication with the interior of the cylinder and with the live steam supply.
  • :i relief valve for engine. cylinders con-iprisiug a receptacle having one end cnnstituting tln ⁇ exhaust end and adjacent thereto having a valve seat, means adjacent to the valve seat for connecting the receptacle to the interior otl thc engine cylinder, means adjacent to the end of the. receptacle remote.
  • nd adjacentthere- -to having a valve seat means adyacent to iis fin 0nd of the rvcvpturle remote from the wlw 5mn, provided with an inward projection entering Lbs piston or - ⁇ valve, the valve boing pr1, v.ided with packing engaging l'he inner Wnl 0

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Control Of Turbines (AREA)

Description

APPLIOATION FILED MAY 15,1908.
B\ 0 YEARWOOD & R G PATTISON AUTOMATIC CYLINDER RELIEF AND VACUUM VALVE.
B. 0. YEARWOOD 6L' R. G. PATTISON.
AUTOMATIC CYLINDER RELIEF AND VACUUM VALVE.
' APPLIOATION num MAY 15, 190s.
903,530. Patented N0v.1,190s.
2 SHEETS-SHEET 2.
athnmqo l UNITED STATES PAIENI OFFICE i mW-m 'fili-W AND or PoR'rsi-lonirn, 'viiu'aiuru ASSIGNORS F ONfi-FOlfn'ri-I 'ro .pionnen soi-rucrnu, or fiocco, oi-ionollpy ATOMATIC CYLINDER RELIEF AND VACUUM /Alll-VliliV specification of Leitern Patent. i
Application filed May 15, 1908. Serial No. 433,085.
iwtzented'Nov. 19118.
' lieten-'ringito the drawing', und niore partirulnrly to lli l, there is shown u cylinder l cons-limiting the hotly ot the vulve, und :it one rml this-*cylinder is 'formed in-to a neck tlnrmled on the exterior :for a. distance us indented :it to f u. purpose which lwill pres# rntly uppcur. (,)n the interior@ `thecylin- \.\hereitfjoine Vlie necl'r 3, tl'tere is .To all 'whom it Amay concern.' g
e it, known that. we, Brno t). ,Ynnuirooo i :nul Romain.' (f. .li'rri-sox. citi' s olt thug United Sintes, residing nti. llo] ...nouiln in.: the county of Norfolk. und Stute o.' v'i|.{i:.1ie, have invented u new und useful. Aul'zunut-ii: (/yl'indvr :Relief und Vneuuin Via-tre. ot
which the followiilg .is u Speelticution. der l This invention lun` reference to inip'rore- ,'l'orxntul un :uinulur tlnnge orledge. oil-onev 'lo ments in uutonmtic relief und vmuuinl furent which there formed 'u vulve seat 6 vulves, and is designed more particule-id v for to which reference will presently be inside. use in connection with the cylinders of loco-` 0u one side of the cylinder 1 is formed a mot-ive engines, although upplicnble to other liaise or .supportv 'a' internully threaded as inneen. l j flicntetl at; ri to receive n threaded nipple lby l5 The purpose of the present. invention tio i menne of' `which the vulve is connected" to relieve any excess pressure .in the engine cyli the casing 9 between the power cylinder l() inder due to witter or mcuurn therein. so of the engine und-the piston vulve cylinder tluit when an engine drifting the recipro ll in the particular strueture illustrated in cutting piston will not muse u vneuum on one Figs?. P, und, 1. The interior ofthe'biise orside und produce undue or excess pressure support 7 communicates with the inteiio'r'oil on the 4other eide, but the two ends of the the cylinder 1 through us'uitable port :12. cylinder willbe connected together or to the ,Projecting from one Side of-fthe cylinder. l external atmosphere so that; the pressure is near the end renxote from the neek iS a relieved and (he tendrjiuey to forni n. vacuum boss? l?) intern-.illy threaded for the reception' 2.3 is: destroyed. 1 nl u pipe 14- und coninnlnicuting with the rlhe invention cr'nuprises u vulve structure interior of the cylinder .l through n port 15'. ilrwhieh springs nre omitted Hinf'e they are l The enti of' the cylinder l remote from the liable to become corrmiled or get out of order. neek I5 is rlosed by :i hend lt securely bolted und the vulve is so omistr'ucted that the ini- .in pince so :is to be steunt tightwit'h the cortial pressure of St cuni in the .Qteurn chest4 will renfooi'ldii'lgr endof the cylinder ltior'rned Seur. the valve und hold it in its sentl while on the inner face ofthe head 16 is u central differential, preszure between the steam chest; projertiing member 17 entering. ythe interior side und eylinrfler side ot' the vulve results in of the cylinder 1 for a distoiiceend located the vulve remaining wide open when the enconcentric tl'ierewith. The projecting meinlurine is drifting'. lier 17 receives au annular piston 18 entering The invention will be best. understood the annular ehuxnher 19 formed between the from u considei-'etion of the following de'l outer walls ofthe extension 17 and the inner tailed (inscription taken in iconnection with wall of the eyljnder 1. On the outer face the uccompnnying drawings forming a-pnrt of the cylinder 18am n nuinber of ribs 20 A10 of this sj'meilicntion, in which (lrnwings in which are formed annular grooves 21 for Figure 1 'is a longitudinal sect-ion of u the reeeptionpofpecking rings 22 andinthe vulve constructed in acorn-(linneo with the outer fnee o't' the projection 17 .are annular present. invent ion. Fig. 2 is fr section on the grooves 23 receiving pecking rings 24 which line .'\--B of Fig. 1. Fig-3 4is a side elevubeer against the inner .talee of the piston 1, tion ot un engirur. cylinder and adjacent where it mores upon the outer for-e of said parte` Showing; t.wo connected vulves at the projection 17. '1y-he pir-:torY 18 ut "the end re- Lwo ends of the cylinder. Fig. 4 is an end .mote from the heur] 16 is formed with' u -levatzion of the structure shown in Rig. 3. vulve sent 25 shaped to engage the sent 6 Fig. 5 4is un end elevation of n modified form when the piston is moved toward the rightl :3o of. the invention. Fig. 6 is n front elevation ms viewed in Fig.' 1. The chamber 19 is oil. the :onstruction shown in lliff. 6' with in Afree con'nnunica-tion with the pi e 14 through the port 15w'hile 'the interlr of parts in Section.
. being located at one end of the cylinder and the other valve at the other end, and the pipe -14 of these two valves Ahave a common connection 26 with the live steam side of the piston valve or steam chest 11. It is to be 4observed that the end wall 27 of the piston 18 is within the chamber 19 and end wall 28 communicates with Suppose no'w that steam is admitted to the the opposite I steamV chestfor the purpose of driving the main engine. The live steampressure 1s exerted against the end vwal1`27V of the piston 18, since the chamber 19 is at`al1 times in communication with the live steam side of the steam chest 11, The piston 18 is immediately forced toward the right as shown in Fig. 1, until' the valve 25 is firmly seated against the valve scat 6 and the port; 12 is thereby closed. Any live steam pressure within the cylinder 10 is unable to move the piston 18 awa from' the seat 6, since the effective area of e wall 28 is less than the effective area .ofthe wall 27 and consequently the .valve piston 1 8 remalns in the closed position sov as the locomotive engine is operating un er normal conditions. If, now, steam be cnt o from the Steam chest and from the cylinder 10 and the engine be allowed to drift, t e locomotivev cylinder will force the valve open and-the vacuum created in the steam connection will vhold the valve open even against a greater vacuum in the locomotive cylinder, owing to the difference in area of t e two end walls ofthe iston or valve 18. In practice, the area of t e wall' 27 is from en per cent. to twenty per cent. greater, than the effective areav ofthe wall 28.
The=va1ve forming the sub'ect matter of the present invention is simple in construction and for its operation relies entirely on the presence or'absence of steam pressure in the steam chest and 'will operate equally well under high and low steam pressures. The valve is applied as closely as possible to the steam ports so as to avoid a wasteful increase in clearance which is a natural defect in the piston valve en ine. From a stand oint of economy in fue two valves are use in each cylinder, since i only one valve were used in each cylmder and were connected by the'nec' essary pipe to the two'steam ports, a lar e volume of steam at boiler pressure wou d fillthis pipe at each and every stroke of the piston' when the engine is working under steam and' then the volume of steam that fills the pipe is exhausted to the atmosphere the port 12.,
valve is o )e1-ated entirely without having done any useful work. Fur thermore, tlfe valves opcn and close only when the locomotive throttle is opened or closed. and their life is thus greatly lncreased and the cost Aof repairs is correspondingly reduced.
In order to prevent any foreivn matter from being drawn into the cylinder or the cylinder lubricant from being blown out to `the atmosphere, and also to keep the cylinder walls warm so as to reduce the initial condensation in the cylinder when the vlocomotive throttle is reopened, after the engine has been drifting, the two valves are connected together by a pipe sutliciently large to carry the hot gases and air'from one end of the cylinder to the other, and the reverse when thL` two valves remain open andthe engine is drifting. The pipe indicated. in the drawinfr by the reference numeral 27 and at eaci cndf enters the corresponding neck 3 of a valve casing 1. The neck 3 where entered by th pipe 27 is suitably counterbored to receive a packing gland 28 and packing 29, while a flanged collar 30 is screwed upon the threaded portion 4 of the neck 3 and serves to hold the gland 28 and packing 29 in place. l
So far as the operation of the valve is concerned in relieving the vacuum and pressure alternately created by the reciprocation of the engine piston, the pipe 27. may be omitted and the ends of the neck 3 remote from 4the casing l may be freely o ened to the atmosphere. `Under these com itions the air is simplydrawn into thc engine cylinder and again fori-cd out on tluI return stroke of the piston.l thereby preventing vthe vacuum or excessive back pressure in the locomotive cylinder, but the presence of the pipe 27 by preventing the initial condensation in the cylindersiF-f the cylinder walls remain warm when the engine 1s drifting, results in a further saving of fuel.
It is to be observed that the valve consists of practically three parts, namely, the valve prop cr, the valve casing, the valve head, and all springs and other' partsliable to corrosion or to get out of order nre omitted, whi le 'the bythe presence or absence Ao steam presure. 4 y
lVhen the envine is drifting, and the valves at the two ends of the cylinder have been forced open by the compression inthe Alocol motive cylinder andare held o en by the vacuum created in the steamfcylmder, then there is an unobstructed passage from one end of the cylinder through the ports and i connecting pipe to the other end of the c linder so that tie gases may freely tlow ack and fort-h as the piston reciprocates in the engine cylinder. The two relief valves,
therefore, lremain open, until the 'locomotive lthrottleis again open at which time the pm in the Walls-of sure through the port 15 acting on the 2T ot" the valve piston 1S closes the 'alvc. Sisal-ld there occur at any time an excess of pressure in the engine cylinder then thc valve will automatically-*open and relieve such 'excess pressure. 'y
The valve meets all the requirements of the piston valve and compound locomotive. The valve particularly adapted to coin pound engines since it readily adapts itselt to the varying pressure that the high and low pressure cylinders are subjected to.
The principles upon which the relief valve are constructed are applicable to other connections than the one shown in the drawing and it is to be understood that theinvention is not limited to the exact construction and location of the parts illustrated and described, but these parts may bc modified as the necessities of service may demand. The valve is, also, applicable to the walls of the cylinder by boring a chamber in the walls of t-he cylinder connecting both live steam portsi rl`he chamber or port will perform the same function as the connectii'ig pipe Q7 between the valves and will, also, form the body oi' cage for the valve. This arrangement is shown in Figs. 5 and G, where the connecting port is indicated at. 31, and the live steam ports indicated at communieating at each end with the connecting port. 31. At the ends of the connecting port. or passage 31 the walls of the cylinder are counter-bored, as -shown at 33, to receive a cylinder 34,-housing the piston 18, while the ends of the connectingare formed into af valve seat 6 receiving the valve '2G on the end of the piston 1S. The outer end of the cylinder 3l is carried to a point flush withthe end of the locomotive cylinder body and a head 41G is there applied with the. central projecting member 17, as in the structure shown in Fig. 1. The cylinder 34: is provided with a porty 35 corre. spending to the port 15 ofthe struct-ure of. Fig. ,1, and thisiportis in coinmnx'iication through a pipe 14 with the live steam side of the steam chest.
Itv will be seen that the structure of 5 and 6 is the saine as that of Figs. l. to et, except that the valves are entirely housed the locomotive cylinder and the only exposed parts are the pipes 14 and 26. The operation is the same as that already described with reference to the struc ture of Figs. 1-to 4.
What is claimed is z- 1. A relief-valvel mechanism` for engine cylinders comprising a suitable differential valve member at each end of the cylinder and in communication with the correspond 'port or passage 31 ing end of the interior thereof, a means of eomn'iunicaziion between the. steam chestand 'all each valve on i l i l the side thereof remote from, its seat, and means of t'ifcc connnunii-ation between the valves at their seat ends.
An cabine tirada-r having formed in. its walls 4at cach end a receptacle having a 'valve seat, said receptacle communicating near one end with the interior o the cylinder :i the respective end of the latter, and said cylinder also being formed 'with a chan nel connectin' the two receptacles at the valve seat endl's, and a valve' in each receptacle, said, receptacles having means of coinnnniication between the ends thereof remote from the valve seats and the steam chest o the cylinder.
3. A relief valve for' engine cylinders comprising an annular 'open ended piston.n
'or valve member, and a. receptacle therefor having al valve seat near oneend for the valve and a head at the other end provided with a central, inward projection, entering the annular piston, and along which the piston or valve is movable, the said receptacle also having' means of communication with the interior of the cylinder and with the live steam supply.
4. A 'rcliet' valve for engine cylinders coinliirising a differential valve at each end ofthe cylinder7 and connected with the interior thereof, a means of communication between each valve and the steam chest, and a connection between the sides of the two valves remote -from that connected to the steam chest, for placing` thc two ends ot' the engine cylinder in communication when the va ves are open. i
5. :i relief valve for engine. cylinders con-iprisiug a receptacle having one end cnnstituting tln` exhaust end and adjacent thereto having a valve seat, means adjacent to the valve seat for connecting the receptacle to the interior otl thc engine cylinder, means adjacent to the end of the. receptacle remote. from the valve seat t'or connecting;l the said receptacle with the steam chest of the cylinder, an a inular open ended piston or valve housed in the receptacle and movable longitinlinaliy therein and a closure for the end of thel receptacle remote from the valve seat., provided with :in inward projection enteringr the piston or valve.
(5. A, relief valve for engine 'cylinders compris-nig a receptacle having one end con,
stituting,r the exhaust. end, a
nd adjacentthere- -to having a valve seat, means adyacent to iis fin 0nd of the rvcvpturle remote from the wlw 5mn, provided with an inward projection entering Lbs piston or -`valve, the valve boing pr1, v.ided with packing engaging l'he inner Wnl 0| h receptacle and the projection llwng provided with packing engaging the xnner wnl of the valve.
In testimony that we claim the foregoing as' our own, we have here'to axed our signatures in the presence of two witnessses.
BYRI) OLIVER YEARWOOD. RBERT` UTTLER PATTISON.
Witnesses:
KATU-1 ICLLERS, F E. GERKE.
US43308508A 1908-05-15 1908-05-15 Automatic cylinder relief and vacuum valve. Expired - Lifetime US903530A (en)

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