US2627813A - Proportional pumping apparatus - Google Patents

Description

Feb 10, 1953 v. J. lLMoRE PRoPoRTIoNAL EUMPING' APPARATUS 5 Sheets-Sheet 1 Filed July 3l, 1947 Gibb @xlk nu /NVENTP VINCENT J. GILMORE @Ma/u1 fad ATTO NE YS Feb. l0, 1953 v. J. GILMORE. 2,627,813

PROPORTIONAL PUMPING APPARATUS I Filed July 31, 1947 5 Sheets-Sheet 2 s un 'n :n

3 u S vo 2 o VINCENT J. GILMORE Feb.; l0,` 1953 v. J. GILMORE PROPORTIONAL FUMPING APPARATUS 5 Sheets-Sheet 3 Filed July 51, 1947 VVE/V70? VINCENT :I GInmom:

BY 'QW' M W A770 EYS Feb. `10, 1953 y. J. GILMORE PRoPoRTIoNAL PUMPING APPARATUS Filed July 51, 1947 5 Sheets-Sheet 4 /M/E/vo/P Vmcmr J. @muon BY Sum, Nga-u A770 EYS Feb-10, 1953 v. J. GILMORE PROPORTIONAL PUMPING APPARATUS 5 Sheets-Sheet 5 Filed July 3l, 1947 mmm.

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. m ENmJ. m. MJ@ mw mv. VYQM Patented Feb. 10, 1953 UNITED STATES PATENT OFFICE PROYORTIONAL PUMPING APPARATUS Vincent J. Gilmore, Wappingers Falls, N. Y., as-

signor to The De Laval Separator Company, New York, N. Y., a corporation of New Jersey Application July 31, 1947, Serial No. 765,169

(Cl. 10S-6) 5 Claims. vl

'Ihis invention relates to pumping apparatus for delivering two liquids in predetermined relative proportions, as for the purpose of mixing the liquids for chemical reaction. More particularly, the invention relates to an improved pro- Iportional pumping apparatus of the type having a pair of reciprocating pumps for the respective liquids, which is rugged and durable in construction and is adapted to pump the liquids at high delivery rates in accurately measured proportions.

In proportional pumping apparatus as commonly used heretofore, the reciprocating pumps for the two liquids have their pistons interconnected so that they move in unison, at least over part of the respective pumping strokes. The intake and discharge valves for the pumps are operated by the pumps themselves; that is, they are actuated directly by the respective pistons or pisproportioning is particularly pronounced in apparatus of large capacity for pumping highly viscous liquids, such as vegetable and animal oils.

The object of the presentinvention, therefore, is to provide an improved proportional pumping apparatus adapted to deliver the liquids ,inproportions which are maintained accurately within extremely close limits, even at high capacities and .under severe conditions of use.

A pumpingapparatus made in accordance with the invention comprises a pair of reciprocating pumps for the respective liquids to be proportioned, valve mechanism connected by a separate .duct to each pump cylinder, and a power vsource for actuating the valve mechanism in lsynchronism with the pump pistons, whereby each liquid is iirst drawn through the valve mechanismand the connected duct to thev corre-A sponding pump cylinder during one stroke of the piston, and is then forced back through the duct and valve mechanism and through an outlet from the latter during the next stroke of the piston. Preferably, the valve mechanism is of the rotary type and includes a separate valve housing and rotor for each pump, the two rotors being connected to each other and to `the power source for the pistons; and in order to obtain continuous ow from the apparatus each housing is connected by a separate duct to an additional pump for the corresponding liquid, so that the two Valves control the flow to and from' a 4pair of parallel-operating pumps for each liquid. This construction aords a high degree of exibility to the apparatus, in that an additional valve mechanism can be connected in parallel to the existing valve mechanism when the latter is insuicient to accommodate the full pumping capacity; or the pumping capacity can be increased by simply connecting additional pumps to the respective Valve housings, without the necessity of any additional valve mechanism.

Since the kvalve mechanism is driven positively and continuously in synchronism with the pump pistons, the apparatus is adapted to maintain .an accurate proportioning of the ypumped liquids at all times. It is important, of course, that the duct connection for each pump be changed from the inlet to the outlet of the valve mechanism, or Vice versa, at the end of each piston stroke and before the next stroke is commenced. Otherwise, the apparatus may be damaged or the accuracy of the proportioning may be impaired, or both. Accordingly, the apparatus is so constructed that the pistons have a short dwell after completion of each stroke, so that the valve mechanism will have ample time to reverse the pump connections through the ducts before the pistons begin their next strokes.

For this purpose, I prefer -to connect the power source to the pistons through a reciprocating crank arm, or the like, which includes an adjustable dash-pot operable to provide a lost motion when the crank arm reverses its motion at leach end of its stroke.

In its preferred form, the apparatus also includes an adjustable connection between the powersource and the valve rotors so as to permit a fine adjustment of the latter relative to the pump pistons, whereby the reversal of the valve connections for the pumps may be accurately timed in relation to the piston movements. This adjustable connection preferably comprises a chain and sprocket drive-in which one of the sprocket wheels is rotatable relative to an adjacent disc secured to the wheel shaft. One of the disc and wheel members has a radial slot, while the other has a slot inclined at an acute angle to the rst slot. A pin extends through the two slots to couple the members and is adjust- .able in the radial` slot to cause relative rotation of the members through an angular displacement corresponding approximately to the length of one of the chain links.

For a better understanding of the invention, reference may be had to the accompanying drawings, in which Fig. l is a schematic view of a preferred form' of the new apparatus;

Fig. 2 is a cross-sectional view of the valve and a pair of positive displacement pumps for one of the liquids, showing the valve inlet and outlet and the connections between the valve housing and the pumps;

Fig. 3 is an enlarged longitudinal sectional view of the dash-pot connection between the power source and the pump pistons;A

Fig. 4 is an exploded perspective view of the means for adjusting the connection between the power source and the valve mechanism;

Fig. 5 is a iront view of a modified form of the adjustable connection between the power source and the valve mechanism, and

Fig. 6 is a sectional view on the line 6-6 in Fig. 5.

For illustrative purposes, the apparatus will be described in connection with the pumping of vegetable or animal oil stock and the usual refining agent, it being understood that the oil and liquid reagent are to be pumped in predetermined relative proportions for a mixture of the two and subsequent rening of the oil. The apparatus may, of course, be used for pumping other liquids as well.

Referring to Fig. 1, the apparatus as illustrated comprises a power source, such as an electric motor i driving through a gear reduction and speed control device I I, so as to drive a sprocket wheel I2 and a crank I3. The sprocket wheel I2 is connected through an endless chain I4 to a sprocket wheel I on a shaft I6 which is rotatable in the frame (not shown) of the apparatus, the wheel I5 rotating synchronously with wheel I2 but at one-half the angular speed of the latter. At its opposite ends, the shaft I6 is connected to the rotors of valves I'I and I8 for the liquid reagent and the oil stock, respectively.

The crank I3 is connected through co-acting crank arm sections and 2I, forming a dashpot which will be described presently, to the depending arm 22 of a walking beam 23 adapted to rock on a pivotal axis 24. The beam 23 carries at its opposite ends a pair of transverse rods 25 and 25e. Pistons 26 and 21 are connected to the opposite end portions of rod 25 and form the movable parts of single-acting, positive displacement pumps 28 and 29 for the oil and the reagent, respectively. Similarly, the rod 25a is connected at its opposite end portions to pistons 268 and 2la forming the movable parts of singleacting, positive displacement pumps 28a and 29a for the oil and the reagent, respectively.

The valves I'I and I8 have inlets 3l and 32 for the reagent and the oil stock, respectively, leading from suitable tanks or other sources (not shown) for the two separate liquids. The oil valve i8 is connected by separate ducts 33 and 33a to the oil ypumps 28 and 28a, respectively; and the reagent valve I 'I is connected by separate ducts 34 and 34a to the reagent pumps 29 and 29e, respectively. As will be described in greater detail presently, the rotors of valves I'l and I8 are driven together so as to connect the pumps 29--23a and 28--28a first to the inlets 3I and 32 and then to outlets 35 and 36, respectively, whereby the oil and reagent will flow first in one direction and then in the other direction in the ducts 33--3?a and 34-34a. Preferably, the ducts 33 and 34 communicate with pressure relief valves 3l and 33 having drain pipes 39 and 40, respectively, and the ducts 33a and 34a communicate with pressure relief valves 37a and 38a having drain pipes 39a and 40a, respectively. The outlets 35 and 36 from the respective valves Il and I8 lead through air traps 4I and 42 to a common pipe 43 where the two proportional liquids are mixedand passed on to a further stage 44 in the refining process.

The valves Il and I8 are identical in construction, and therefore a description of the valve I8 will suffice. As shown in Fig. 2, the valve I8 comprises a frusto-conical housing 46 which is closed at its ends. The oil inlet 32 leads into the bottom of the housing, while the oil outlet 36 leads from the top of the housing in diametrically opposed relation to the inlet. Ports 4'I and 41e open into diametrically opposed sides of the valve housing, so that these ports and the inlet 32 and outlet 36 are spaced 90 apart around the conical periphery of the housing. Within the housing 46 is a frusto-conical valve member or rotor 48 having two diametrically opposed longitudinal vanos 49 and 50. The vanes 49 and 50, which are slightly wider than each of the four ports in the housing, iit closely against the peripheral wall and the end walls of the housing and divide the interior thereof into two diametrically opposed, arcuate chambers 5I and 52. The valve rotor 48 is adapted to be rotated aboutl its axis so that the chambers 5I and 52 move continucusly around the interior of the Valve housing. v

The ports 4l and 47a are connected through the ducts 33 and 33a to the cylinders 54 and 54Iu of pumps 28 and 2821, respectively. Each cylinder is provided at its open end with a cap which retains a packing gland 56 around the piston of the pump.

As previously mentioned, the'crank arm sections 23 and 2I form a dash-pot between the crank i3 and the walking beam 23 for actuating the pistons. More particularly, the section 2l) has a longitudinal bore or chamber 58 which is open at one end, the bore having an annular recess or enlargement 59 intermediate its ends (Fig. 3). The adjacent section 2I has a plunger or slidable part 21a extending into bore 58, and a sleeve 66 secured to plunger 2Ia, as by means of a transverse pin 2lb. The sleeve 60 ts closely in bore 5B and has an annular external recess 6I which, with the recess 59, forms an annular oil chamber having a supply opening normally closed by a threaded plug 59E. At each end of its recess 6I, the sleeve 60 has longitudinal oil grooves 62 leading to the adjacent end of the sleeve. Near the outer end of sleeve 66 is a guide bushing 63 threaded in bore 58 and having a central opening in which plunger 2|a is slidable. The bushing 63 also has a recess for sealing rings B4 which are clamped in position around the plunger by a metal ring 65 held at one end by a cap 66 threaded on the bushing. At the outer end 6l of section 26 is a washer 68 Awhich is engaged by a shoulder on the bushing when the latter is screwed into bore 58, whereby a clearance space 69 is provided between the inner end of the bushing and the opposing shoulder formed by the outer end of sleeve 65 when the plunger is in its innermost position in the bore.

With the parts positioned as shown in Fig. 3, the section 2] is moving to the left and engages closed -end lof the" bore. Avprovided Ain the 4plunger rmovement depends, of f course,` upon the extent of the fcIearancespace '-AGSand-.upon the rate of l'flow throughgrooves-62 which,`in turn, depends upon the size-and number Lthe inner" endfof plunger 21eandfsleeve 60' so that the .latter partsmove toV the -left'with" section '20. When. section 20 reaches the tend A.of its wstroke and reverses-its movement, the-:load (represented byf the 'pumpwpistons Lonplunger. 21|

"will Vpreventzthe latterfrom `mov-ing withfsection20 until the inner'.endlofbushing engages `the opposingiendof 'sleevefGIL "However,A such engagement .cannotfoccurf-.until the oil is `forced out of clearance Aspaceii'i and a corresponding Vv`volume offo'ilfhasfbeen; forced into* fthe clearance "space -which, due to'movementrof 'the bore rela- 'tive f to the-plunger and sleeve, fforms at "the The timefdelay-*thus of the grooves. It will be understood that a similartime delay is provided at thenextreversal of the movement of section 20, since the plunger 4will not'be engaged by theclosed end ofthe bore'vuntil the oil is forced out ofthe intervening clearance space` and a corresponding volume of `oil is simultaneously returned to- 'thefclearance space 69 .f which forms during-the movementof 'the bore relative to the plunger and sleeve. By substituting a washer 68 of diierent'thickness; 4the-"length Vof theclearancespace 69 and therefore the time delay maybe variedv as' desired.

The sprocket wheel I5 is adjustable angularly on its shaftV I6. Asshown in Fig. 4,'-a disc10 is -splined to shaft I6 and has; a projecting Vhub v1I which fits intoV the central opening inwheel I5,

the -wheel'ibeing rotatabley onv theV hub. The disc" also has `a radial-slot1l2,; and the sprocket wheel has a slot 13 extendingat an acute angle to slot 12, the slot 1-3-.preferablyv extending at an angle of about 45 to a radius intersecting the latter. The vlengt-hof slot 13' is such that its effective length, referred to a tangenti to the radius taken at eitherfend oflthefslot. willequalthe length of one .link of chain I 4. A bolt 14 extendsthrough the slots 12 and 13, and .by .adjustingthe radial vposition vof the bolt in slot 12, theiangular position of the wheel I5 on its shaftmaybe varied. The

`sprocket. wheel is clamped in its adjusted position on disc 10. by a nut 15 threaded on theprojecting .zend of the bolt. If desired, theldisc maybepro- -vided witharcuate slots 1B for. receiving addfitionf1; al .clamping bolts 11 which areth-readed. inopenings' 16a in the sprocketwheel.

-A lmodified form of the adjustablesprocket `wheelis shown in Figs.5..and A(i. .As there shown.

disc 1I)EL splined to shaft I6. A screw 18 extends radially in slot 12a in the disc and has a block The pump pistons 2S, 21 and 26a, 21a are recipro cated by crank I3, the crank arm sections 20, 2I and walking beam 23, while the rotors of valves I1 and I8 are driven together continuously by.v shaft I6 from sprocket wheels I2 and I5 and theirv interconecting chain, in synchronism with the piston movements. However, the sprocket wheel `damage to the apparatus.

I5y and the crank I'Bare drivenat d-iierent'speeds.

. as :pointed out previously, f so that vthe crank? and 4,therefore ,the pump :pistons will 'undergo two complete .cycles vduring each complete revolution of shaft'I and the valve-rotors. vThus, assuming that rotor 48v of the oil valve rotates clockwise asy shown in Fig. 2, theoil-piston/ZG will ibe moving downwardly and the other oil piston 26a will .be moving upwardly when rotor 48 is in theposition illustrated Consequently, oil is forced out of cylinder 54 'through duct 33, arcuate chamber` 5I and outlet 36, while oil :flows in through inlet 32 and through arcuate chamber -52 and duct 33B to the other :oil cylinder 54a. Each piston reaches the end of lits stroke ator slightly before the instantzwhenthe vanes -49 and 50 vreach theports. 41 and"41,

respectively. From this instant, a short time intervalV elapses before theA vanes` 49 andL Ell-'can passfover the-respective ports to their Opposite sides; but during this interval the time -delay afforded bythe dash-pot connection 20, 2-Ijprevents the pistons'from commencing theirfnext strokes. When the pistons commence their' next strokes, the vanes lwill have moved rfar enough to connect duct 33 through chamber 52to inlet 32,and'to connect duct 33EL through chamber 5I to-ou'tlet 35. Accordingly, the upward'stroke of'piston 2B will permit oilto ow into its cylinder from inlet, 32, and the downward stroke of piston 2lia will force-oil from its'cylinder'through*outlet'36.

The pistons 25 and '26a will reach `the ends of their respective upward anddownward strokes at or slightly before the instant when vanes'49 and 50 completely reach the ports' leading to-out let 36, and inlet 32, respectively. Because'of" the time delay provided by dash- pot connection 20 and 21, the pistons will not commence their next strokes until after vanes 49 and 5i) have passed rover the. respective outlet and inlet ports by-mov .ing clockwise beyond the latter. Thereupon, the downward strokeof piston 26 forces oil through duct 33 and chamber 52 to the outlet, and the upward stroke of piston 26a allows oilA toflow in from inlet 32, chamber 5 I and duct 33a,- whereby anew cycle for each piston isl commenced.

The operation of valveA I1 is the same-as that Apreviously described in connection Vwith valve I8. 'Piston 21 forces reagent-through duct 34,-valve I'1and outlet'35at the same time thatA piston 26 'forces oil throughV outlet 35 and while pistons 21 and 21aL allow oil and reagent to `enter Vfrom inlets 32 and 3| through ducts 335l and 34a, respectively. The valves I1 and I8 lreversethelr respective' connections at `the-same instant, a-nd the pistons 21 and 21a move in unison with the pistons 26 and 26a, respectively. Accordingly, the reagent and the oil will flow substantially continuously through the respective outlets 35 and 36 for subsequent mixture in pipe 43. The relative proportions of the outflowing oil and reagent will depend, of course, upon the effective areas of the pistons 26, 2ta in relation to the eifective areas of pistons 21, 21a.

The relief valves 31, 31EL and 38, 38a will open in response to excessive pressures which may be created accidentally in the respective ducts, so that the liquid will escape through the relief valve and its drain pipe and thereby prevent The-air traps 4I and 42 are adapted to remove air from the liquids and reduce the pressure pulsations incident to the pumping action.

By means of the adjustable mounting for sprocket wheel l 5, the position of the valve rotors 'may be readily and accurately adjusted relative tothe pump pistons, to cause the valve connections to be reversed in the proper timed relation to the piston movements. In practice, the chain i4 is arranged on sprocket Wheel I5 in a position as near as possible to that corresponding to the correct timing, and the final adjustment for less than the length of a chain link is made by adjusting the relative positions of disc I9 and wheel I5, as previously described.

It will be apparent from the foregoing that I have provided a proportional pumping apparatus in which the valve mechanism for reversing the pump connections is driven continuously and positively in synchronism with the pistons, so that the apparatus can be operated at high capacity to maintain Within extremely close limits the proportioning of even highly viscous and sticky liquids. Also, with the new apparatus the pumping capacity can be easily increased by simply connecting additional pumps to the valve ducts 33, 34 or 33, 34a, it being unnecessary to provide additional valve mechanism; and if the pumping capacity is too great to be handled by the existing valve mechanism, additional valve mechanism can readily be connected in parallel thereto. The added pumps can be driven from the rods 25, 25a on the walking beam, or from extensions of these rods. The additional valve mechanism can be driven from shaft IE.

The apparatus is preferably arranged so that the liquids to be proportioned iovv into the respective pumps by gravity, whereby the feed through inlets 3l and 32 is not dependent upon suction created by the pumps.

I claim:

1. A proportional pumping apparatus for delivering two liquids in predetermined relative proportions, which comprises a pair of cylinders for one of the liquids, a second pair of cylinders for the other liquid, a piston reciprocable in each cylinder, a rod connected to one piston of each of said pairs of cylinders, a second rod connected to the other pistons, a rocker arm pivoted intermediate its ends and connected at its end portions, respectively, to the rods, a valve housing for each of said pairs of cylinders and having a separate inlet and outlet, ducts connecting each valve housing with the respective cylinders, a valve rotor coacting with each housing and movable to connect one of thecorresponding cylinders to the housing inlet and the other to the housing outlet through the respective ducts and then to reverse said last connections, a driving connection extending between the valve rotors,

and mechanism for operating said rocker arm and driving connection in synchronism.

2. A proportional pumping apparatus for delivering two liquids in predeterminedv relative proportions, which comprises a ported pump cylinder for each of the respective liquids, a piston reciprocable in each cylinder, valve housing means for each pump cylinder having an inlet and an outlet for one of the respective liquidsa duct leading from the port of each pumpcylinder to the corresponding housingA means, valve rotor mechanism coacting with each of the housing means and mounted for continuous movement to connect each duct alternately to the corresponding inlet and outlet, actuating means, and separate driving connections leading from the actuating means to each of the pump pistons and the valve rotor mechanism for actuating the same in timed relation; i

3. Apparatus as defined in claim 2, comprisin also a lost-motion device forming part of said separate driving connection to the pump pistons.

4. Apparatus as denedin clairn2, comprising also areleasable device forming part of said separate driving connection to the valve rotor mechanism, said last device being releasable to permit adjustment of the valve mechanism relative to the actuating means.

5. Apparatus as deiined in claim 2, comprising also a releasable device forming part of said separate driving connection to the valve rotor mechanism, said last device being releasable to permit adjustment of the valve mechanism relative to the actuating means, and a lost-motion device forming part of said separate driving connection to the pump pistons.

' VINCENT J. GILMORE.

REFERENCES CITED,

The following references are ofrecord in the le of this patent:

UNITED STATES PATENTS Ferris et al Jan. 11, 1949

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