US2582709A - Feed mechanism - Google Patents

Description

Jan. 15:, 1952 E, 1N 2,582,709

FEED MECHANISM Filed Dec. 21, 1949 6 Sheets-Sheet l FIG. I INVENTOR.

EUGENE MARTIN AHo ney Jan. 15, 1952 MAR-N 2,582,709

7 FEED MECHANISM Filed Dec. 21, 1949 6 Sheets-Sheet 2 ,WW WWW Attorney Jan. 15, 1952 E, MARTIN 2,582,709

FEED MECHANISM Filed Dec. 21, 1949 6 Sheets-Sheet 3 INVENTOR. EUGENE MARTIN BY Attorney Jan. 15, 1952 E, MARTIN 2,582,709

FEED MECHANISM Filed Dec. 21, 1949 6 Sheets-Sheet 4 E UGENE MARTIN A f forney Jan. 15, 1952 E. MARTIN 2,582,709

FEED MECHANISM Filed Dec. 21, 1949 6 Sheets-Sheet 5 INVENTOR. EUGENE MARTIN Attorney E. MARTIN FEED MECHANISM Jan. 15, 1952 6 Sheets-Sheet 6 Filed Dec. 21, 1949 INVENTOR. EUGENE MARTIN fififiwzu Attorney Patented Jan. 15, 1952 I I Eugene Martin;Wesleyville, Pa), assignor-to Bead; v I

. S andard Gor o a n a rn ra onl f i el r w ra- I This invention relatesito improvements in ap-. paratus for feeding: granular or.- finelypdivided I solid material from a hopper; or 1 other source; to 1 a receiver wherein a" pressure differential. exists:

between thehopper and-theireceiverw Onemformiof such"device; 'disclosed;in my ape plicationSerial No.148A62; filed September 1 9,

1948, embodies a pair of feedvalves, movably supported within a valve'bodyhaving an upper feed-.uinlet and a lower feed outlet; The feed valves are operatively connected"tomeans-disposedlwithin the body: for alternatelyl moving them: to and away from. respective vertically spaced valve seats extending, inwardly of the inner wall softhe valve body and defining a feeding chamber between them. Valve? con-f trolled means is. providecla for pressurizing athe feed chamber whilethe upper and; .:-lower feed valves are olosedin order 'toifacilitaitejopeningit of the lower feed valve against thefpressure: in;

ap licant :nemba 21, lsisgseriarNa 134,321 Q4 claims, ,(01. 214-'-1j7}. I

Other objects and advantages of the invention; residing inthe construction and combination of parts willbecome apparent from the following description when: read in'connection with the accompanying drawings disclosing a preferred embodiment of the invention. n

Inthedrawings; Figure l'is a vertical central sectional view through: the novel feed device with parts shown in,- -,elevation; I

Figure 2 is a sectional view taken on theline 2''2 of Figure'l;

Figure 3 is a sectional-view taken on the line' 3=--3'--of'Figure 1-; 1' i p Figure4' is an enlarged V-fragmentary sectional view taken on the line 4--4 of Figure 2' showing the feed. valves, the V actuating means therefore Figure 5: isa sectionalview taken on the line v the receiver andto facilitate discharge of the:

material from the feed chamber into, there-r; ceiver. Valve controlled means, is -;also providediifor venting the pressure-in-the, feed chamber after the lower feed valve re-closes :land" before i the upper feed valve opens, in ordertoprevent blow back of pressure intothe feedahoppen- -7 Sequential timing means 1 automatically-i controls? the proper operating sequence-ofithe feed valves; 1 the pressuriz'ing valve and theivent'val-ve. In the said application there is disclosed operatingmeans within the valve body for opening and closing the feed valves including cylinders and hydraulically operated pistons disposed therein.-

'An object of the present invention is to. provide in a feeding'apparatus offlthe type de" scribed; improved hydraulic opera-ting; means that permits employing larger cylinders without' 1 increasing the overall size of the feeder, whereby less fluid pressure is required for operation of the feed valves; I

Another object, of the invention is to providean improvedconstruction and arrangement ;of the lower feed-"valve and the cylindrical housing that supports the feed valve and encloses; the; operating means for the valve to facilitateopen' ing of the lower feed valve againstithe pressureexisting in the pressurized receiver.

Still another object ofthe invention istof provide an improved compactly arranged feeding device of the type described that' is simplein construction, eflicient in. operation andembodies improved and compactly arranged means for controlling the sequential operationof 'the material feed-valves, the chamber pressurizing valve and the-chamber vent valve. 7

andl'the housing supporting thefeed valves and housingthe actuating; means, the feed valves being shownin their -seated: position; v

5'.--5'of,Fig ure 2 with the, upper feed valve shown iniits' open position; p 7

Figure-56:15 a sectional view taken on; the line B2-6::of Figure 2 with the lower feed valve shown in its 'open position v a Figure 7 isa fragmentary; sectional view of one of. the-ball-check valves in the cylinder heads ofthe valve-actuatin g; means; I Figures-is a view in-elevation of the invention 7 showing the; arrangement of; :the; pressure fluid distributing valves, the'pressurizing valveand the" ventvalve on the'body of the feedrnechanism, with--parts in section to showthe' cam shaft' and' cams foractuating the valves;

Figure 9 is. an enlarged fragmentary sectional view takenon-the line 9-9 of Figure 2 ofthe" pressurizing valve; I v

Figure 10'is an enlarged fragmentarysectional view taken on the use I'0--l0 of Figure 2 'of the vent valve; and 1 Figure 11 is a diagrammatic view of the" c'a',r1i's showingtheir relative positions;

1 The invention is' hereinafter described with": reference to the feedingof f finely dividedco'al" into a pressurizedreceiver;however, it will be. evident that it maybe employed for feeding var-i:

ous kinds of granfi'l'ar'lor finely divided solid materials.

Referring tothe'drawings," particularly Figure" 1, the feeding device comprisesa preferably cylindrical jvalvebody l0 open" at the top and bottom; The upper'end of the valvefbody I0" communicates with a coal supply hopper II and the lower end thereof communicates with a" pressurized tank or" receptacle [l 2i Operating" mechanism located outside thevalve' body It) and the valve body itself, are preferably enclosed by a housing l3 attached in suitable manner to the valve body [0.

Considered from top to bottom, the wall of the valve body It) tapers to form an internal annular ledge |4,- then expands abruptly and tapers again to form a second internal annular ledge 15, and then expands again for its remaining distance, to define within the body a coal receiving chamber l6, a pressurizing cham-' ber 11, and a discharge mouth 18. An annular valve seat I9 is detachably secured in any suitable manner, as by bolts 20, to the upper annular ledge 14, and is provided with a non-metallic yieldable seat ring 21. The seat ring 2| is firmly secured to the valve seat I9 by bonding or other 1 suitable means. In similar manner, an annular valve seat 22 provided with the non-metallic seat ring 23 is detachably secured to the lower annular ledge l by bolts 24. I

Disposed in the upper end of the chamber 16 axia--y concentric with the cylindrical valve body 16 is a hub shaped open ended housing 25 which is attached to the valve body by four preferaoly equally spaced radial arms 26, 21, 23

an 2c, as best shown in Figure 2. The valve body 15, hub shaped housing and arms 26, 21, 26, and 29 are'preferably formed as an in-, tegral casting.

A valve assembly, designated as a whole by the numeral 30, is pendently supported within the valve body [0 from the hub shaped housing 25 by suitablemeans, such as the bolts 51, shown in Figure 2.

The valve assembly 30 includes a cylindrically shaped valve Support 32 axially disposed within the valve body I0' and extending downwardly from the hub shaped housing 25, with which it is in register, through the chambers 16 and |1-into the discharge mouth I3. A removable cover plate 33 forms a closure for the lower end of the cylindrically shaped valve support 32.

Telescopically mounted on the valve support 32 and supported thereon in a manner herein-v after described, is a lower valve 34 arrangedito seat upwardly against the lowervalve seat'22; Similarly mounted and supported on the valve support 32 is an upper valve 35 arranged to seat upwardly against the upper valve seat 19 Referring particularly to Figure 4, the lower valve 34 comprises a cylindrical sleeve-like upper portion 36 arranged in telescoping engagement with the valve support 32, a flared skirt portion continuing to an inwardly tapering portion 38 and terminating in a sleeve 39 arranged in bolts 41, shown in Figure 1, is a packing retain "ing ring 48 arranged to receive suitable packing 49. The packing 49 embraces the cylindrical portion 36 of the lower valve 34 providing a seal against leakage of pressure and coal dust from the chamber 11 past the cylindrical valve portion 36.

A packing" retaining 'ring 50 embracing the cylindrical portion 43 of the upper valve 35, is secured in any suitable manner as by the bolts 5|, shown in Figure 1, to the annular flange 52 which is formed with and projects outwardly of the upper end of the valve support 32. Suitable packing 53 within; the retaining ring provides a seal against leakage of coal dust past the cylindrical valve portion 43.

Upper and lower valves 35 and 34 are operated by hydraulic motors 54 and 55, respective- 1y, disposed one above the other within the valve support 32; The upper hydraulic motor 54 comprises/a cylinder56 having a' piston 51 reciprocable 1 therein and' arranged to be actuated in opposite directions by hydraulic'fluid. Similarly,

the lower hydraulic motor comprises a cylinder 58 having a piston 59 reciprocabletherein and arranged to be actuated in opposite directions by hydraulic fluid.

Theup'per motor cylinder 56 is closed at'its upper end by a cylinder head 60 and the lower motor cylinder 58 is closed at its lower end by a cylinder head 6|. Acylinder head 62 'common to the two hydraulic motors '54 and 55, forms a closure'for the adjacentlower and upper ends,

respectively, of the upper and lower motor cylinof bolts 63' that project through the'cylinder head 60, extendalong the outside of the cylinder 56 40 and are threaded at their opposite end intothe cylinder head 62'; and. bolts54 that project through the cylinder head 6|,"extend along the outside of the cylinder 58 and are threaded at their opposite end into the cylinder head 62.

telescoping engagement with the valve support 32.

Depending from the lower valve 34 and securedthereto in any practical manner, as by the bolts. 40 shown in Figure l, is a packing retaining ring 4| arranged to receive suitable packing 42. The packing 42 embraces the lower portion of g the valve support 32 providing a. seal against leakage of pressure and coal dust past the sleeve 39. V V

The upper valve 35 is generally similar to the lower valve 34. Again referring particularly to Figure 4, the upper valve 35 comprises a cylindrical sleeve-like upper portion 43 arranged in telescoping engagement with the valve support 32, a flared skirt portion44 continuing to an inwardly tapering portion 45 and terminating in a cylindricalsleeve 46 arranged telescopically to receive the cylindrical portion 36 of the lower. valve 34.

Depending fromthe upper valve 35 and secured thereto in any practical manner, as by the The common cylinder head 62. is provided with a fiange'GFarran'ged to seat on an inwardly extending annular flange'66 formed with the valve support 32; Suitable means, such as bolts 61,

ex'tend'through the flange 65 into the flange 66 to rigidly secure the motors 54 and 55 'withthe valve support 32. 1

A piston rod 68 is secured at one end to the piston head 51 of the upper motor 54 and projects therefrom upwardlythrough the stufling box 69'of the cylinder head 60, while a pistonlrod' 10 is 'secured'at one end .to the piston head 59 of the lower motor 55 and projects therefrom downwardly through the stufiinglbox 1| of the cylin- The upper valve 35 is connectedwith the free end of the piston rod 68 and the lower valve 34 is connected with the tree end of the piston rod 10,1b'y means hereinafter described,iwhereby re- -ciprocating'movement of thepiston rods 68 and 10 is transmitted to the valves 35' and 34, respectively. The cylinderheads 60, BI and 62 are preferably provided with 'ball check valves I41 to insure quick opening of the valves. An enlarged view of one of the check valves I41 is showninFigure '1.

The connecting means for the upper valve 35 includes a yoke 12 secured'as at 13 in Figure 4, to the free end of the piston rod 63. Threaded thefree ends' of the diametrically opposite asserted In order to actuatethe piston '51 of the upper motor 54, twocoriduitsor pipes .88,;89are"provided which are connected respectively with the upper and lower ends of the :motor .cylinder 56 through a passage-90 in the upper cylinder head 60 and a passage 9I in the lower cylinder :head 62, as-best shown in respective Figures?) and 6, and means is provided to -supply fluidun'derpressure through one of these pipes while allowing fluid to escapeifrom theother pipeand-vice-versa. Similarly, to actuate the piston '59 of thelower motor 55, two conduits or pipes 92, L93 are providedwhich are connected respectively with the upper and lower ends of the motor cylinder 52 through a passage :94 in the upper cylinderzhead 6'2 and a passage -95 in thelower cylinder head 61, asbest shown inirespectiveFigures 5 and 6, and meansis provided to supply fluid under pressure through one of these pipes while allowing fluid :to escape from thelotherpipeand vice versa.

The radial arms 26, 21, :28, 29 formed with the Valve body I are provided respectively with passages 9'6, 9'I, 98, SILthroughtwhich the respective conduits-'or pipes 93,02, 88, 89 extend, as'shown in'Figure 2, to the fluidmeversing meanslocated outside the valve body I'll. This means may be any suitable Well 'known type of 'valve mechanism such-as a :Vickerscam operated 4-way valve, type C-47-2-EA. One such valve-is shown at I110, which is connected with the-pipes 88 and :89 for controlling the flow of fluid to the cylinder 56 of upper motor 54, and another such'valve isshown at IOI, which isconnected'withthespipes 92 and 93 for controlling the flow of 'fluid' to .the .:cylinder 58-of lower'motor '55, "as best shown-in Figure 8. The valves I00 and 'IIJI areisuitably securedxside by-side on the outsideofthevalve body ID. A feed'lineJ-AS and a return line I46 connect the distributing valves I00 and IOI with :a'suita'ble source of" fluid under "pressure.

The cams I02'and I03 for operating the valves I00 "and I0 I; respectively, aremounted on a shaft I-M disposed"horizontally above theivalves I00 and I01I. A housing I05 for the cams I021andl03-is rigidly secured tothevalve .bodyzl'ficand isprovided'at'its ends with bearings, I0.6,and I0I:in

which the oppositeends of theshaft I04. are journa'led. The shaft I04 "is :operated from'a motor ['03 through any suitable speedxreducing means.

The cams I02 and I03 are constructed ,andarranged, as will be hereinafter described "in greater detail, to effect acertain sequence of events during each revolution lofthezshaft I04. Starting, for example, with the .cam .followers I09 and IIO'o'f valves I00 and IOI,.'respectively, in engagement with the high parts of cams I02 and I03, both of the material feed valves 34 and 35 are closed, asishown in Figures 1 and 4. Then, when the cam follower I09 .of valve:I0,0 engages the low part of cam 'I02-while the cam follower II-0 of'valve IOI is-.still inzengagement with'the highilpart oftgam rI 03, upperzfeed waiver-3 5: opens while slower reed :valve 34 :remains closed. as shown in :Figure ;5, whereupon @the :finely divided coal or other material :can :drop by gravity yfromchamber litintorchamber I1. Following this the cam follower I 0910f" valve .el-nmre-engages ;the :high part of cam 1.02 while the .cam follower H0 of valve :ILOI still in engagement with :the high. part :of .cam I03, whereupon upper feed *valvei35 is again-closed;andilower vdeed valve 34, of course. remains closed. Finally, the team follower 110 of Lvalve 1IOI engages the low part of cam I03 while the cam follower llflflnof valve I00,is,still in =engagementwith the high part of cam I02, whereupon :lower i-feed :valve '34 lopens, as shown insEigure :6, and -theifinely divided coal ,or other material :can .'.drop :by :gravity from charnber ;I 1 into discharge imouth 11.8. T'hecycleis then re peated for: each revolution ofthe. shaft I04.

In order to :facilitate discharge of coal :Irom the :chamber :I'I through the discharge mouth 11-8 and into the pressurized meceptacle I2 when the lower 'feed valve 34 opens,=valv,e controlled means is provided ,for introducing air under pressure into the chamber 1;! above the charge of coal disposed therein. Valve controlled means iszalso provided for venting or exhausting the pressure trapped -.in chamber I! after the :coal :has been discharged therefrom andthelowerifeed valve 34 has .closed, and :before the upper yfeed wvalve 35 has ireopened.

'The operation :of lthe valve 'lcontrolled pressurizing and venting means, just referred to, 51$ synchronized .with the opera-tion of :feed' valves 34and'35, sorthat allzfourio'f these elementsrfunc tion in a regular :sequence for ;each revolution of :the'shaft PI 04, :as hereinafter described.

Referring ffirst ito :the .valve controlled .pressurizing means, with regard particularly :to Figure '9, thevalve body I0 is vprovided in the wall thereof adjacent the ledge "I4 with "an annular passage -1I-I..I :that stops short of making .a ;com-' plete circle 'by'the walls :8 and .9, see Figure 3, fora purposeilater-explained. 'n'pluralitytof circumferentiallyspa'ce'd :jet openings II2rprovide communication betweenrthe'rpassage III :and the upper .end of chamber 'II wherebyai-r under pressure .is admitted in high pressure jets to chamber I! above :the coal (therein =for facilitating discharge of coal. Pressure is admitted to the passage I1 I :through the -,port I I 3 from the supply pipe I:I.4 which :leads froma :suitable source :ofzsupply Knotshown) ,-A valve I I5,- interposedibetween :the supplypipe I14 and; port I I 3,, controls =the=delivery1of air un der :pressure to the passage I- I I, and is disposed immediately above the housing I for the'cam operating shaft I04, asbest shown Figures -8 an'dzv9. The avalve 3 I1 5 comprises fa-casing II-6,

secured: in any suitable-manner to thevalve body I-0,=and hasaninlet; port I'II communicating-with supply pipe I I4 and anoutlet port-H8 communicating with the port I I3.

internally, the valve I15 is ,provided with-a seat H9 for receiving the valve member I20, and

Wall thereof adjacent? the 1edgeTI4 with achain ber I26, disposed-between the walls 8 and 9 that define the ends of. the annular passage III, as best shown in Figure 3. A port .I2'I provides communication between chamber I26 and the upper end of chamber II and a port I28 opens from chamber I26 exteriorly of the valve body. I0. The walls'8 and 9 closing off the chamber'l26 from the annular passage III, prevent the high pressure air from escaping into chamber I1 through the large port I21 and insure a jet action of the-air through -the jet openings II2.

-A vent-valve 'I29,controlling the exhaust of air pressure from the" chamber I1 is. disposed immediately above the housing I for the cam operating-shaft I94, as best shown in Figures Band 10. The valve 1'I29 comprises a casing I30, se-" cured in any suitable manner to the valve body I0, and has a discharge port I3I communicating with a'vent pipe'l32 and an intake port I33 communicating with the port I28. I I

Internally, the valve I29 is provided with a seat I34 for. receiving the valve member I35,

and a spring I30 normally'ret'ains the valve mem-. ber I in its seated or closed position. The valve stem'I3'I of valve member I35 extends through the lower sleeve portion I38, which forms a guide for the valve stem I31. The lower end of the valve stem I31 projects into the housing I05 and carries a cam follower I39 responsive to a cam I mounted on the cam operating shaft I04. I i g The timing 'andorder of operation of the coal feed valves 34, 35, the'pressurizing valve H5 and the exhaust valve I29 is determined by the shape and" position of the cams I02, I03, I25 and I40. around the. cam shaft I04. Figurell' is a diagrammatic representation of the cams I02, I03, I25 and I40, with their respective cam shoulders 'I4I, I42, I43 and I44 shown in their proper relationv for controlling the operation of the. valves'34, 35, H5 .and I29. With the cams I02, I03,'I25 and l40'as shown inFigure '11, both feed valves 34 and 35 are closed as in Figurev 1, the pressurizingvalve H5 is closed as in Figure 9, and the vent valve I29 is closed as in Figure 10; I With the camshaft I04 rotating in the .direc"-' tion indicated by the arrows a sequential opera tion of the feed valves, pressurizing valve and vent valve-occurs during each'revolution of the shaft. First the cam shoulder I44 of cam I40 engages cam follower I39 and effects opening of the vent valve I29," then camshoulder I4I of cam I02 dis-engages cam follower I09 and effects operation of distributing valvel00 to a position providing for passage'of pressure fluid through.

pipe 88i'to'the upper end of the cylinder'53" of hydraulic motor 54, whereby upper feed valve 35 is o'pe'ned. Both 'feed valve 35 and vent valve I29' re'main' 'open for "an interval, during which coal drops 3 by ravityinto jchainber- I1 and the air displaced-thereby is consequently, permitted to freely exhaust throughvent valve I29. Upon continued rotation'of cam-shaft I04, cam "shoulder I44 of cam I40 disengages cam follower I39 whereupon the spring I36 closes the vent valve I29. Following this, cam shoulder I4I ofcam I02 engagescam follower I09 and efiects operation of distributing valve I00 to'a position 'whereby pressure fluid is admitted through pipe 89 beneath the piston5l of hydraulic motor 54 and pressure fluid above the piston 51 isvented' jthrough pipe 88, whereupon upper'fedvaive'is closes.

III)

An interval later cam shoulder I43 of cam;

I25 engages cam follower I24 and effects opening of pressurizing valve II5 whereby fluid under pressure as high or preferably higher than the pressure in the tank or receptacle I2 is admitted to chamber I'I through the jet openings II2. Thereafter, cam shoulder I42 of cam I03 disengages cam follower H0 and effects operation of distributing valve IN to a position providing for passage of pressurefluid through pipe 92 to the upper end of the cylinder 58 of hydraulic motor 55, whereby lower feed valve 34 is opened. Both feed valve 34 and pressurizing valve II5 remain open for an interval, during which coal drops from chamber II into receptacle I2. Since the pressure on the head of coal in chamber I! is at least equal to the pressure in receptacle I2. the coal freely empties from the chamber I1, and the jets of pressure fluid issuing from the jet openings II2 further facilitate discharge of .coal from the chamber I'I.

Upon further rotation of cam shaft I04, cam shoulder I43 of cam I25 disengages cam follower, I24 whereupon spring I2I closes the pressurizing valve II5. Following this, cam shoulder I42 of cam I03 engages cam follower H0 and efiects operation of distributing valve IM to a position whereby pressure fluid is admitted through pipe 93 beneath piston 59 of hydraulic motor 55 and pressure fluid above the piston 59 is vented through pipe 92, whereupon lower feed valve 34 closes.

The above cycle of operations is repeated for each revolution of the cam shaft I04. The cams I02, I03, I25 and I40 may bemodifled to alterthe timing of the valves, however, at all times. the lower feed valve '34 should be fully closed before the upper feed valve 35 opens; the upper feed valve 35 should be fully closed before the lower feed valve opens; the pressurizing valve I I5 should be fully closed before upper feed valve 35 opens; and vent valve I29 should be fully closed while lower feed valve 34 is open.-

I claim:

l 1. In a material feeding device, a body providing a pressure chamber between two valve seats, a valve support extending lengthwise through said chamber forming between the periphery of said support and said valve seats an annular inlet to the said chamber and an annular outlet from the said chamber, an annular inlet. valve extending. about said support movable lengthwise therealong and cooperating with one of said seats to control said annular inlet, an annular outlet valve extending about said sup-. port movable lengthwise, therealong and cooperating with the other of said valve seats to control said annular outlet, valve operating means within said valve supportfor actuating said valves, said valve support being open at its lower end provid ing access to said operating means without disassembling said valves, and a removable cover for said opening: y

' 2. In a material feeding device, a body provid-i ing a pressure'chamber between two valve seats, an inlet valve movable lengthwise to the chamber and cooperating with one of said valve seats to control'the inlet to said chamber, an outlet valve movable lengthwise to the chamber and cooperating with the other of said valve seats to control the outlet from said chamber, a valve support lengthwise to the chamber, valve operating means within'said' valve support including pressure fluid cylinders disposed one above the other arida'common cylinder head" for theadja-i cent ends of said cylinders, and means rigidly securing said cylinder head with said valve support for supporting said valve operating means within said valve support.

3. In a material feeding device, a body providing a pressure chamber between two valve seats. an inlet feed valve cooperating with one of said valve seats to control the inlet to said chamber, an outlet feed valve cooperating with the other of said valve seats to control the outlet from said chamber, a valve support in said chamber movably supporting said inlet and outlet feed valves, pressure fluid operated motors in said valve support for actuating said inlet feed valve and outlet feed valves, a pair of pressure fluid distributing valves outside said body for controlling the operation of said motors, means including a valve connecting said chamber with a source of pressure, means including a valve for venting said chamber, a rotatable shaft outside said body, and a plurality of cams on said shaft arranged 10 to successively contact the stems of said distributing valves, pressurizing valve and vent valve forxs'equential operation thereof.

4. A construction according to claim 3, in which the cams are arranged about said cam shaft to efiect for each revolution thereof sequential operation as follows, opening of said vent valve, opening of said inlet reed valve, closing of said vent valve, closing of said inlet feed valve, opening or said pressurizing valve, opening of said outlet feed valve, closing of said pressurizing valve and closing of said outlet feed valve.

EUGENE MARTIN.

REFERENCES CITED UNITED STATES PATENTS Name Date Gieseler Feb. 22, 1921 Number

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