US 2593316 A
Description (OCR text may contain errors)
April 15, 1952 EL ROY J. KRAFT 2,593,316
RECIPROCATING PUMP ASSEMBLY Filed neo. 23, 194e -2 SHEETS-SHEET 1 April 15, 1952 EL ROY J. KRAFT 2,593,316
RECIPROCATING PUMP ASSEMBLY Filed nec. '23, 194e 2 SHEETS- SHEET 2 lll/1 |r///////////////,
Patented Apr. 15, 1952 UNITED` STATES PATENT OFFICE RECIPROCATING PUMP ASSEMBLY El Roy J. Kraft, Oak Park; Ill., assignor to The Dole Valve Company, Chicago, Ill., a corporation of Illinois Application December 23, 1946,Y Serial No. 717,953
' in the feed conduit to the pump when the valve is closed, and arranged to eject pressured uid from this surge into the pump as soon as the valve is opened.
Surge chamber arrangements to steady the discharge of reciprocating pumps are known, but heretofore surge chambers have always been on the discharge side of a reciprocating pump. According to this invention the surge chamber is provided on the intake side of a fast-operating reciprocating pump, not for the purpose of steadying the intake feed to the pump, but for the purpose of greatly increasing the capacity and pumping rate of the pump.
This invention provides an arrangement which momentarily absorbs the surge of liquid in the feed conduit to a reciprocating pump when the intake of the pump is closed during the pressuring cycle of the pump, and builds -up inlet pressure from-the kinetic energy of the flowing fluid for ejecting the pressured fluid into theinlet as soon as it is opened on the suction intake cycle of the pump.
Suitable surge chamber arrangements for carryingout the principles of this invention can take any one of a number of different forms. For example, a resiliently expansible hose section can be included in the intake conduit to the pump, a rigid hydraulic ram chamber can be provided on the intake conduit supplying the pump, or a spring-pressed piston slidably mounted in an expansion chamber communicating with the intake conduit for the pump can be used. The hose section will swell up due to the surge of liquid upon cessation of flow to the pump, thereby momentarily storing a slug of liquid under pressure adjacent the pump inlet for forced ejection into the pump on the next cycle of operation. The hydraulic ram chamber will be filled with air that is compressed when the surge of liquid causes some liquid to flow into the chamber, and the compressed air back of the liquid is eective to eject it into the pump on its next cycle of operation. The spring-pressed piston arrangement I in an expansion chamber functions by receiving liquid forced into the chamber during the surge upon cessation of intake ilow, and by pushing this liquid into the intake of the pump on its next cycle of operation.
A feature of the invention resides in the provision of a very fast-acting and eillcient intake check valve for the pump. This check valve closes instantaneously upon change of the pump cycle from suction intake to pressure discharge so that flow of fluid in the intake conduit is instantaneously stopped, thereby enhancing thel surge of fluid to create a greater pressure buildup from the kinetic energy thereof. Conversely, the intake valve opens immediately upon change of the pressure cycle to the suction cycle of the pump and makes possible the immediate utilization of the inlet pressure built up in the surge chamber arrangement.
Another feature of the invention resides in the provision of a surge chamber on the intake side of a pump having an interrupted intake operating through high speed cycles to develop kinetic energy in liquid'ilowing to the intake with a sufflcient momentum to tend to maintain a con-- tinued ilow while absorbing the flow or surge into the surge chamber during those portions of the interrupted flow cycle of the pump. l The high speed of the pumps of this invention'tends to build up a wave motion in the intake flow and the surge chamber absorbs the crests of the waves to utilize their force for ejecting the liquid into the pump on the next open cy-cle thereof.
. It is, then, an object of this invention to pro-` vide a device having an interrupted flow intake with a surge chamber on the intake side thereof arranged to build up inlet pressure from the kinetic energy of the flowing fluid.
` Another object of the invention is to provide a reciprocating pump assembly with a surge cham.
ber on the intake side thereof. t
A further object of the invention is to provide a device having an interrupted fluid intakeV cycle with -a check valve operating in response to cycle conditions and means in advance of the valve for building up inlet pressure, `when the valve .is4 closed, from the kinetic energy of fluid ilowing. to the valve and for ejecting the pressured fluid said passageway.
ber slidable on the body member and having an end face with an axial opening therein for receiving fluid from the passageways when the end face is spaced from the body member and for sealing the passageway when the end face iS against the body member.
A still further object of the invention is to provide a check valve for pumps and the like composed of a disk with a thickened central -portion having a plurality of passageways therethrough arranged in spaced relation from the axis thereof, together with a metal cap'member slidable on the thickened portion of the disk and carrying a sealing liner for coacting with the end face of the thickened portion to close Other and further objects of the invention will be apparent to those skilled in the art from the following detailed description of the annexed sheets of drawings which, by way of preferred examples only, illustrate several embodimentsof the invention.
AO n the drawings:
Figure l is an end elevational view of a pump assembly according to this invention.
Figure 2 is a vertical cross-sectional view, with parts in side elevation, taken along the line II-II of Figure 1, and showing the intake cycle of the pump assembly.
Figure 3 is a fragmentary view similar to Figure 2, but illustrating the discharge cycle of the pump- Figure 4 is a View similar to Figure 3 but illustrating a hydraulic ram surge chamber arrangement in place of the resiliently expansible hose section.
Figure 5 is a View similar to Figure 3 but illustrating an expansion chamber having a springpressed plunger in place of the expansible hose of Figure 3 and the hydraulic' ram of Figure 4.
Figure 6 is an enlarged axial cross-sectional View of the check valve in the pumps of Figures 1 to 5.
Figure 7 is a plan View of the body of the check valve.
Figure 8 is a plan View of the cap member of the valve.
Figure 9 is a plan view of the sealing liner for the cap ofthe valve.
As shown on the drawings:
In Figures 1 and 2, the reference numeral I3 designates generally a pump assembly according to this invention. Anl electric motor II is provided for driving the pump and, for this purpose, has ashaft I2 projecting therefrom and carrying an eccentric I3. A bearing I4 surrounds the Y eccentric and a strap member I5 surrounds the bearing. The strap member has a slot I5a in the top end thereof providing furcated arms which receive aligned bearing sleeves I6. A cross pin I1 is mounted in the sleeves I6.
A frame or bracket I8 is secured on the end of the motor I I and has a boss portion I9 carrying a bearing overlying the strap I5. A pump piston 2lV is slidably mounted in the bearing 26 and Vhas an eye end 2I a in the slot 15a of the strap and receiving the cross pin I1 therein. The cross pin is locked in the eye end of the piston by means of a pin 22.
The bracket I8 has a cylindrical pump housing 23 on .the upper end thereof above the boss I9.
This Vhousing 23 has a well 24 extending upwardly from the bottom thereof and receiving packing rings 25 therein. The piston 2| slides through the rings 25 into the pump bore 26. The piston fits freely in the bore 26 and operates to displace fluid therefrom. A packing plate 21 extends into the well 24 and is urged against the bottom packing ring 25 by means of bolts 28 extended through a ange 21a of the plate 21 and threaded into ther bosses 23a on the pump housing 23. These screws 28 are tightened to force the member 21 into the well thereby compressing the packing material 25 and maintaining a leakproof seal around the piston 2|. I l
The body23 has a side nipple 29 providing an intake port for the pump bore or chamber 26.
The nipple 29 has a stepped bore therethrough including an Vinternally threaded outer end portion 36, a first .shoulder 3I, a first restricted bore portion 32., a second shoulder 33. a second restrcted bore portion 34. and a blind bore portion 35 of smaller diameter than the portion 34. Passageways 36 join the `bottom of the blind bore 35 with the interior of the pumping chamber 26. The pumping chamber thereby has a side intake.
An intake check valve 31; has the body portion 38 thereof bottomed on the shoulder 3l, and has the cap portion 39 thereof confined for movement Within the bore portion 32 because the shoulder 33 limits the movement of the cap 36 off of the body. A coil spring 40 is bottomed on the blind bore portion 35 and acts on the cap 39. A hollow fitting member 4I is threaded into the portion 36 of the bore and is internally threaded for receiving a hose nipple 42 in threaded relation therein. This nipple 42 has a bulbous portion 42a near the kend thereof. A rubber hose 43 is stretched over the fitting 42 around the bulbous portion 42a thereof and a hose clamp 44 secures the hose on the fitting. Y
The top of the housing 23 has a well 45 therein and a second check valve assembly 46, identical with the assembly 31, has the body portion thereof seated in the lbottom of the well. A hollow fitting member 41 is threaded into the well 45 against the body of the check valve 46 and Vhas a stepped bore therein providing a chamber for the cap member of the valve as well as an abutment for the spring of this cap member. discharge conduit 48 is threaded into the tting 41. l
The eccentric I3 rapidly reciprocates the piston 2| in the pump chamber 26 from the suction intake position shown in Figure 2 to the pressure discharge position shown in Figure 3. On the intake, or downstroke, shown in Figure 2liquid from the hose 43 is sucked into the pumping chamber 26 through the inlet passages 36. On this suction stroke, the cap member 39 of the intake check lvalve 31 is drawn against the shoulder 33 thereby allowing fluid fiow through the check valve.A
As best shown in Figures 6 to 9, the check valve 31 has the body member 38 thereof in the form of a circular disk. A thick cylindrical central portion 38a of reduced diameter is formed integrally onthe disk and projects from one face thereof. vThis thick portion 38a has aflat end face 38h. The lcap member 39 of the valve 31 has a circular end wall 39a with a cylindrical skirt 39h projecting therefrom and slidable on the cylindricalv thick portion 38a of the disk. The cap 3.9 has a liner disk 43 composed of rubber, fiber. plastic, or the like in the cylindrical skirt 39h thereof andibottomed on the end wall 39a.
The body member 38 has a plurality of longitudinal passages 3.80 extending through the thick portion .38a thereof in radially,spacedrelation from the axis of the body. As shown in Figure 7, sixpassage's 38C are provided' and they are equally spaced around the axial center of the body. f i
The cap member 39 has an aperture 39c in its end face 39a thereof at the axial center of the cap. An aligned aperture 49a is provided in the sealing disk liner 49.
vWhen the liner 49 is bottomed on the end face 38h of the body member, the passageways 38e are'effectively sealed. However, when the cap member 33 is moved to carry the liner 49 thereof away from the end face 381), a iiow path is opened up between the passage 38e and the apertures 49a `and 39C.A thereby accommodating fluid flow through the check assembly. The skirt 39h, in riding on the cylindrical portion 38a of the body 38, prevents cooking of the cap and insures full seating of the liner on the end face 38h whenever the valve is closed. The valve is very rapid in operation, has relatively high capacity for its size, and can be made very light in weight to eliminate heretofore-encountered inertia in check valve assemblies. As soon as the liner of the valve is cracked oii of the end face of the body. fluid will rapidly iiow through the valve, andfconversely, as soon as this liner is pressed against the end face, all ow through the valve is-stopped.` Y
The pumping chamber 26 is filled with liquid on the intake stroke. shown in Figure 2, and the eccentric then reversely reciprocates the piston i 2 ly to pressure the liquid in the pumping chamber and eject it from the pump. As shown in Figure 3, as soon as the piston starts on its upstroke, the check valve 31 is closed and the check valve 46 is opened. Liquid in the pumping chamber 26 is thereby forced through the check valve 46 and into the discharge conduit 48.
The piston 2| is reciprocated very rapidly, so that the pump goes through its suction and discharge cycles at very high speed. During the intake or suction cycle of the pump liquid in the hose 43 flows rather rapidly because of the high speed of operation of the pump, and the flowing liquid builds up considerable kinetic energy. As soon as the intake valve 31 closes. however, the liquid, due to its kinetic energy and momentum, will produce a surge which, unless dissipated, would produce a water hammer effect in the intake pipe 56. According to this invention, however, the water hammer effect is entirely eliminated and the hose section 43 between the pipes 50 and intake fitting 42 is suiiiciently yieldable so that it will expand to the position shown in Figure 3 thereby providing an enlarged chamber accommodating the surge of liquid. Of course expansion of the hose occurs by its ability to resiliently stretch, and, in its stretched psition, the hose material such as rubber, is tensioned or loaded and will assume its untensioned or unloaded condition as soon as permitted. Thus, when the intake valve 31 is again opened on the next suction stroke yof the pump, the liquid filling the stretchedV hose will be immediately expelled under the pressure developed by the tensioned or loaded condition of the hose and will be effectively forced into the pump chamber. As a result, therefore, charging of the pump on its suction stroke is speeded up and made easier because the liquid is actually injected into the pump instead of being drawn against the usual frictional drag occurring in an intake conduit.
The hose section 43 should be positioned immediately adjacent the intake of the Dump and, of course. should be resiliently expansible to Jde- 6 velop a tensioned pressure-producing condition. The hose section should be sufficiently short so that the surge chamber effect is obtained without dissipating the kinetic energy of the iiuid.
In effect, the cycle reversals of the pump of this invention occur so rapidly that fluid flow in the conduit 50 is never completely stopped,
and a wave motion is built up the crests of 'which` are absorbed in the expansion of the hose to forcibly expel the liquid as soon as the intake valve is open.
The pump l0, instead of being equipped with the rubber hose intake arrangement of Figures 1 to 3 can, according to a modied embodiment of this invention, have an intake pipe 5l with a hydraulic ram 52 thereon defining a surge cham-'- ber 53 which is normally filled .with air. On the suction stroke of the pump, liquid iiows rapidly through the pipe #5i to build up an appreciable kinetic force. Upon reversal of the cycle of Vthe pump to the discharge stroke, the valve 31 closes, and the kinetic energyAor momentum of the fluid in the pipe 5i causes some fluid to flow into the chamber 53 of the hydraulic ram thereby com pressing the air therein. This compressedair,
acting directly on theiiuid in the chamber 53,
thereupon effective to eject the iiuid out of the chamber and into the pumping chamber 36 on4 the next suction stroke of the pump. The cycle reversals of the pump are so rapid that the hydraulic ram will absorb the surges of uidoccurring during the pressure strokes of the pump Without stopping flow of the liquid in the pipe 5I and, at the same time, the kinetic energy in the surges is salved for ejecting the iiuid during the next suction cycle of the pump.
In the embodiment of the invention shown in Figure 5, the pump I8 is equipped with a rigid, non-expansible inlet pipe 60 having a flanged nipple l6| thereon closely adjacent the pump inlet. This nipple 6I defines a cylindrical bore 62 in communication with the interior of the pipe 60. A housing 63 is secured on the flanged nipple 6I by means of bolts 64 and has a large bore 65 therein aligned with the` bore 62 and of substantially the same diameter together .with a small bore 66 extending upwardly from the upper end of the bore 65. A vent 61 joins the upper end of the bore 66 with the surrounding atmosphere. A piston head 68 is slidably mounted in the bores 62 and 65 and has an integral rod or stem portion 69 slidable in the bore |66. A coil spring 10 is held under compression between the bottom of the bore and the piston head 68 to urge the piston head toward the interior of the pipe 60. A shoulder 1| in the bore 62 limits the in- -ward travel of the piston.
On the suction stroke of the pump I0, liquid, of course, flows through the pipe 60, and the spring 16 plus the intake suction holds the piston 68 against its shoulder 1I. Immediately upon termination of the suction intake stroke of the pump, the intake check valve 31, of course, closes. and the kinetic energy in the rapidly flowing liquid in the inlet pipe 60 causes the liquid to surge against the piston 68 thereby forcing it upwardly in the bore 62 and compressing the spring 1D. Some liquid is thereupon momentarily stored in the bore 62 and is acted on by the spring-pressed piston which, of course, tends to force the liquid back into the pipe 60. Therefore, on the next suction intake stroke of the pump il), the liquid is pushed by the piston 68 into the pipe 60 and thence, of course, into the pump inlet. The bore 62 and, if necessary, the bore 65 therefore define anfexpansionchamber' absorbing the'fsurge of liq# uid-. caused lb'y :cycle freversals of fthe.'` pump 1f and i1.
utilizngfthe .-'energyiofY th'e 1 surgev =to` gloadza spring i for expelling" the :liquid `on: the next .intake stroke of. .the pumpi The three `embodiments of theinventionillus'.-
trated'ghereir show vthe 'useE of dierentk typespoff:
surge :chambers .fon the` intake side of a recipro catinggpumpfor absorbing a surge of liquidnupon reversal of thel pump cycle from :intake` tozcomz pression, and for ejecting the absorbed liquid underl pressure Iduring :the next intake stroke 'of surge'chambers .a'bsorbingthe crests ofy the waves cee'ding. suction stroke ofthe pump.
.-20.2 to:z-utilizefthey kineticv energy` therein on r,the sucl details of Iconstructionmay'be varied through as widerange-without 'departing from the principles of;this#inventionA and it is,:. therefore,v not'the v. purpose tolimitpthe patent granted hereon otherf wise thanmecesstat'ed bythe scope of theapjpendediclaimp.
Aareciprocatingfpumpcomprising1.a pump body havingf an. open-,ended pumpingjchamber havV ingaicylindricallwall', ailuid inlet leadingthrough said/wall `into saidA chamber, a'V lightweight .valve ,Y
disk Y assemblyL including; a .disk freciprocable in aapistonmovablewithin said chamber-and extendihgsfrom' one-open endv thereof. .said other openflend Lof 1 the .chamber providingps, fluid outleal-alcheckfvalvem `said otheropen end, an out-.1- let ittin'gfanchoringsaid checkzvalvein said' out- V35.52 said inlet to check back-flow fromthefchamber,
lett', an .eccentric pperatiuely;connecteckwithfsaid; piston;tor:reciprocably.fmovesesadl pistonnwithnw. y
said pumping chamber, an inlet fitting anchoring;` said valve diskassemblyin said inlet',iianda..nipp lje carriedzbyfsaid iinlettting; 'ar-short elastic Ltubes.l
onY said nipple ;.forming af r contmuatio'n thereof.;r
tractble :immediate1y;-adjacent..the fnipple-:toia'b sorbsurgesiin said: inlet when the disk.;va1ve'c1oses;; andxtoff. force f'. .vuid f. into .,said; pumping.; chamber". f
The -foil'wing :references fare EOf-ecOrdi'Jinfithel:
Number Name Date- 57,412 /Veydei ,.Aug.- 21,.,1866v 2104,7-.471' Maxim-- ,.June:f11; 187:82 852,150.. WhitneyKA Apr. 30511907:v 912,502'1 Squires f .Feb. 16,; 1909..l 1,075,322 Bargamin .f Oct...14;...1913 s 1,129,072 Conn 1; LEeb.23,-119151,- 1,204,898 Nichols Nov..14;..19.16 1,266,650: Brandenberger x MaygZ l, v1918 1,713,073 Carter; li/lay,145;.1929.1A 1,865,000e f Goldberg@ June. .248, ,1932 1,944,340, Zubatygehal; ,.Jan;-.23',1934:t 1,979,479 Labaw ..Nov.f 631934.15 2,008,133f. Farmer. ,July=16, `1935'w 2,261,948'.. Beach -.Nov.1 11, ,194115. 2,325,672 Groff ...Aug3, 19431.
FOREIGN PATENTS Number` Country` Date 18,106 Norway .....l)"ec.` 14,;190'1.`v