US1239059A - Pump. - Google Patents

Description

A. SUNDH.

rum.

APPIJCATINI FILED OCT. I3. B913- Patented Sept. 4,1917.

4 SNETS-SHEET I.

A. SUNDH.

. PUMP.

APPLICATION FILED OCT. I3. I9I3.

1,239,059. Patent/0d Sept 4, 1917.

4 SHEETS-SHEET 2.

A. SUNDH.

PUMP.

APPLICATIDN FILED OCT. I3. |913.

Patented Sept. 4, 1917.

4 SHEETS-SHEET 4 view in section of a fecting the 'operation UNITED STTES PATENT OFFICE.

AUGUST SUNDH, 0F HASTINGS-UPOIUsHUDSON, NEW YORK, ASSIGNOB T0 OTIS' ELEVATOR 00mm, A CORPORATION 0F NEW JERSEY.

PUMP.

Bpeoiilcation of Letters Patent.

Patented Sept. 4, 1917.

Application tiled Dotober 18, 1918. Serial No. 794,829.

To all whom t may concern:

Be it known that I, AUGUsa SrnmirheJ citizen of the United States, residing 1n Hastings-upon-Hudson, in the county `of Westchester and State of New York, have invented'a new and useful Improvement 1 n Pumps, of which the following 1s a specification.

My inventionrelates to Huid pumps or motors, and more particularly to a reciproeating pump in which the stroke of the plstons or lungers may be varied at will.

One o ject of the invention 1sy the-prov1 sion of a multi-cylinder pump in which the thrust of the plungers on a crank shaft 1s automatically equalized;

Another object is the provislon of 1m- `proved valve mechanism which will avoid churning of the fluid handled by the pump. .Another object 'is the provision of two sets of ump plungers, the stroke -of each set f plJungers being capable of equal and simultaneous `variation.

Another object of the invention 1s the provision of a multiple plunger pump, and a center shifting' device `adapted to vary the stroke ofthe plungers from zero to a maximum in both directions, and means whereby the center shifting device will positively be held in zero position for an alpi p reclable period of time while the stro e of the plungers is being 4reversed or moved through a zero or no stroke position.

A further .object of the invention is the provision of alreciprocatingplunger pump having a center shi ting device for variable pump stroke, said center shiftin devlce comprising a pair of eccentrics whlch may bodily he shifted through zero by a single device, the act of shifting being substantially balanced against fluid pressure.

Other objects of the elementsfbeing 4p ointed out in the appended claims. Y l

In the accompanying drawings, Figure 1 is a side sectional view of a pump contaming an embodiment of my invention; Fig. 2-is a right hand front elevation Vview of the same in part section; Fig. 3 is a detail manual means .for efof the center shifting device; Figs. lLand 5 are sectional detail views of the center shifting'device taken at rightangles toreach othe Figs. 6 and is4 operated by Y tegral as shown,

invention will ap pear hereinafter the novel 'comblnations of,

7 `are diagrammatic views of the valves and plungers, illustrating the operation of the pump; Fig. 8 and exhaust chambers Figs. 9 and 10 are fragmentary Vviews, taken at right angles to each other, and showing in detail one of the shifting eccentricsJ and the method of drivingthe pump plungers thereby; Figs. 11 and 12 are fragmentary views, taken at ri ht angles to each other, and showing one o the iixed eccentrics and thecoperatin'g valve mechanism.

Like reference characters denote similar parts in all of the figures. l I

Referring to Figs. 1 and 2, it will be seen thatthe pump therein shown comprises two sets of seven cylinders each and corresponding Avalves also arranged in two sets, there being seven valves in each set, each' c linder having'its4 own valve. one set are designated by the reference numbers 8, 9, 10, 11, 12, 13 and 14; while the cylinders of the other set are represented by the numerals 15, 16, 17, 18, 19, 20 and 21. Each set of c linders is o eratively connected to a di erent adjustagle eccentric such as 22 and by side on a common crank shaft 24, and each and every cylinder is radi disposed about the axis of the said shaft. he valves foreach cylinder are also radially disposed about the cran shaft, and each set of valves a corresponding eccentric fixed on the shaft 24. The working and valve cylinders, together withA the iuid chambers 25 and 26, are preferably cast inand this casting 'is supported upon a substantial bed 27.

The shaft 24 is made in one piece and is supported toward'either end in ball bearings 29 and 30, whichin turn are supported by the end covers 27 andl 28, respectively, secured to opposite ends of the cylinder casting and forming therewith a crank case 31. 'The plungers of each cylinder together with the correspondingl valves are all o erated from the shaft 24 by means'of t e eccentrics 22,:23, 32 and, 33. The eccentrics 22 and 23, ^which are associated with the p1ungers,"alre arranged and constructed shown in Fi. 1;

lso as to be shifted in planes perpendicular to the' axis of the shaft so as to reverse the stroke of the plungers andV also effect any `desired length of stroke from zero to a The cylin ers' of is a sectional view of the inlet` 23, arranged closely side.

Q2 lo 55 'vn y 'on is eied 6 and v35, which are boltedto ether by the bolts or cap screws 36, 36. pair of reversely threaded screws 37 and 38 pass through parallel holes in the shaft and each screw is secured at either end to the eccentric 10 by means of pins 39. Threaded upon each of the screws 37 and 38 is a pinion 41 and 42, respectively, each of which 'snugly fits a recess provided thereforA in the shaft 24. The center of the shaft is hollow, and contains a rack 40 which meshes with. both of the pinions 41 .and 42. Upon the outer periphery of the eccentric 22 is shrunk or otherwise secured a hardened steel ring 43, which assists the bolts 36 in 'holding the two halves of the eccentric together, and acts as a wearin surface for the anti-friction rollers 44, t rou h which the working plungers are operate The eccentric 22 is provided at' diametrically opposite points withtwo Arejections 45 and 48, which have. a. snu

This construction permits the eccentrics 22 and 23 to slide with respect to each other each 80 .in its own plane erpendicular to the axis of theshaft 24, wiiile at the same time prevents a `relative displacement of the eccentrics 22 and 23, about the shaft and forms a drivin ,connection between the said eccen` trios. he eccentric 23 is provided with projections 49, 4 9, arran ed diametrically7 0ppm-site` each other and sdable in grooves 50, 50, formed in a member 51. The eccentric 23 is provided with a air of oppositely threaded screws such as t e screws 37, and 38,?*of the eccentric 22, one of which, the screws 56, is shownin Fig. 4, but the screws of the eccentric 23 are reversely` threaded with respect to the corres ending screws of, the "eccentric 23 carrly;V pinions 52 and `57 (seeFig. 1)`w'hichmes with' the rack 40. Thememberlis provided withan` eccensecurel keyed tot esliaf't 24byga ky 5 4; an keptin roper position against sii l. -tudin )Leitha shaft, by a flanged co ai" -Since the merhber 51 keyed tq the shaft, andr is in thro 6 49, uhit follows f t the shaft 24`and all 1 foureocexdaricsmustrotateasan'mt l .estafa-repainted one the mais 2 dahima a fa 1 das. con ve( ro o ep means-ofA sli 1n fit with other pro'ections 46v and4 former integral with the ot er cam 23.

of the eccent 'c 22, and eac of the screws izulmvariedsoliste` 40 in the following manner: Referring to Fig. 1, it will be observed that a movement of the rack 40 in a left hand direction causes the pinions 43 and 52 to rotate in a clockwise direction, while the pinions 42 and 57 will rotate in la reverse or anti-clockwise direction. Since the screws upon which these pinions are threaded are fixed against rotation by the pins 39, and since the pinions themselves cannot move within the shaft other thanl to rotate, it follows that the screws are moved bodily in the direction of their length, carrying with them the corresponding eccentrics. Furthermore, since the screw 53 of the eccentric 23 is reversely threaded with respect to the screw 38 of the eccentric 22, and since the corre onding pinions 42 and 57 are both rotas in the same direction by the rack 40, it follows that the movement or 'shifting of the eccentrics 22 and 23 is always in a reverse direction, that is to say the throw of pne eccentric is. always 4one half revolution, or 180 from the throw of the other eccentric, and the respective throws of'each eccentric isalways equal.`

While various wa s could vbe devised for operatin the rack so as to vary the eccentricity o the eccenti'ics 22 and 23, I prefer the arrangement herein disclosed and illustrated in igs. 1and3. This arrangement comprises a grooved collar 58 which is slidable upon the shaft 24 and is connected to the rack 40 by a pinf59, the latter passin through a slot 60 in the shaft. Av yoke lever 61 is provided with pins.62 462, which rest within the groove of the collar 58,` and this lever is secured to a shaft 463 'pivoted to the pump casing" 27.. The-shaft 63.841,50 has aixedfto it a lever 64 which carries a pin 65 ,atits u per end ddapted to 'ride in a cam-slot 66 ormed in a cain cylinder 67. The latter is supported Y bearings 74 and 75, and is provided 44wiltllli 4worin 'teeth 68 which meshw'ith a worm 69 adapted to berotated by'a-handwheel 70, The cam s1ot66 has three distinctY partsnhrportions u designated by the reference numbers 7 1, 72 and 73. The, art 72' is circumferentialand 4of considera e le "h, while the and 73 branch out 1n the slot posite directions. The operation of the center or; shift' devicecomprisingthe hand w eel-70, islas follrwvs:f U 1 n; UP

the hand wheel; 'm' umlgianni-l buaewin "to thelength oftheV j n tial cam 0h72, the' in 65 therein is not at first moved.' ',As the and wheel ebntnues l the para .ma ae aaa-'is maval sm.

rock the levers'64 and `61 to the righ ttor 8S, thermal; may bo', 4The mvmadt leverl 61;,is the' Jins 62, 62, to the sliding collar'58, and the utter is -caused to slide along the shaft 24, carrying with it the rack 40. In this manner it is possible to move `the rack to the right or left as far as it will go, to an intermediate position, and thus va the eccentricity of oth of the eccentrics simultaneously toa-ny desired degree. Owing to the length of the cam slot 72, -it will be impossible quickly to reverse the eccentrics 22 and 23, since an appreciable time must elapse before the pin 66 leaves thel cam slot 72, whenV an attempt is made to reverse the pump. In this manner a qduick reversal of the pump is not possible an all danger of shock and jar is avoided. The Worm 69 is referably of very moderate pitch, so as to e irreversible` say, the cam cylinder 67 cannot be moved by the rack 'no matter what pressure may be brought to bear, but can only be moved when the wheel 70 is turned by hand. Hence it follows that any adjustment to the eccentrics made from the hand wheel remains absolutely fixed ust so long as the hand wheel isnot distu' ed or intentionally rotated.

As before pointed out, each of the eccentrics 22, 23, is operativel -connected to .a separate set of pump p ungers, and` this operative connection will now be described. Surrounding each eccentric, such as the eccentric 22, is a ring 76, (see Figs. 9 and `10) which is preferably made of hardened steel and contains a series of radial projections 77, each having a` dove-tail peripheral slot. A fblock78 isdovetailed in each of these radial prejections, and is adapted to have .a

limited sliding movement therein. The ring 76 has seven equallyy spaced projections 77, and each *of the blocks therein' is Vconnected by av pin 79 to a ump plunger. The ring 76 is concentric to t e eccentric 22', and a series of anti-friction rollers 80, V80, areinterposedf nected to the-seven pump plungers of the- -other set in precisely the same manner as that just described. a

The operative connection between the' ec,` centrics 32 and33 and the variousvalves is very much the same asthe connectionsfbetween the eccentrics 22 and 23, andthe pump ist.

plungers, .excepting in the former case, owing to the relatively small thrust between the valves and the valve eecentrics, lthe antifriction rollers are left out. This construc' tion is very clearly seen from Figs. 11 and 12, and comprises a ring 824 containing seyen equally spaced projections, such as'83, 83, cach of which is dovetailed and contains a correspondingly dovetailed block as 84, which is secured by a pin 85 to one end 86 of the valve. The ring 82 surrounds the That is to opposite ends by means of screw plugs-or other appropriate means. The valves are also similar to each other, and each one,

such as the valve 87 (see Figs. 1 and 2) is com# Dprised of two parts or piston valves 88 and 89, which are connected together and thereby form a two-part valve balanced against pressure and requiring aminimum amount of power to operate. The closed end of each plunger cylinder is connected by a passage or port to the center of a corresponding valve. For instance, in Figs 1, 6 and .7, the lowermost plunger cylinder 18 is connected by a port 1 to the valve 87, said port opening into the valve between the two valve pistons 88 and 89. Other ports such as the ports A and B of each valve are all connected to the fluid chambers 25 and 26, respectively. That is to say, the ports A of all of the valves are in communication through valve are in like manner interconnected through the chamber 26. The chambers 25 and 26 are connected through the pipes 91 and 92, to a source of fluid supply and discharge, respectively, or vice versa.

\ Referring to yFlgs. 6, 7 and 8, the arrangement of the valves and plunger cylinders is clearly shown in dia ammatic form. The full lines of Figs. 7 an 6, represent one' set of seven plungers and the corresponding valves, respectively, while the broken lines represent the other set of plungers, and their corresponding valves. In these figures the mode -of operation of the pump may very clearly be seen. Take for example the cylinder 8 shown at the top in Fig'. 47. The plunger in this cylinder is shown at the tcp of its stroke, while the corresponding valve shown at the top of Fi 6 occupies an intermediate osition, wit the ports A and B closed and a communication between the pluncylinder 8 and thechambers 25 and 26,- t rough the port 1 cut o'. The same conditions exist with respect to the plunger cylinder 18 0f the other set, and its correspond. ing valve 87. Both of these ,plungers are in s. position of no stroke, or, in other words, on their dead centers Su pose for example, that the shaft24 is rotat 1n a clockwise direction. The-piston or lplunger ef cylinder 18 is moved upwardly y the eccentric 23, while the valve 8,7 1s carried dbwnwardly by the eccentric 33,' and the downwardmovement of the valve causes'thevalve piston 87 to uncover the port A and thereby place the c linder 18 in communication with the c amber 25, through the c linder port 1' and valve port A. The cham er 25 is therefore a suction chamber, and fluid will be sucked therefrom into the cylinder 18 as the plunger of said cylinder rises. While the cylinder 18 is acting under suction, other cylinders of the same set such as the cylinder 2l, is undergoing compression. For instance, as the eccentric 23 rotates in a clockwise direction the plunger of cylinder 21 is moved outwardly and forces the Huid in the cylinder throu h the port 5 to the valve 93, and through t e valve port B into the compression chamber 26, the valve piston 94 having uncovered the valve port B.

The operation of all of the plungers and their respective valves is precisely similar to that just described, with respect to the cylinders 18 and 21.1' At no time will more than two plungers ever be passing through a dead center at the same time,and the cylinders under suction and compression are so grouped about the shaft that their reaction thereon is distributed uniformly about a circle, which practically eliminates all bending strain on the shaft and reduces the friction lat the shaft bearings to a minimum. If the rack` 40 of Figs. 1, 4 and 5, be moved so that eccentrics 22 and 23 are concentric with the shaft 24, and the Ilatter be revolved, the pump .plungers obviously will remain stationary, and no Huid will be pumped. If the rack 40 be further moved in the same direction, the throw of the eccentrics 22'and 23 will be reversed, and the puinp as a whole will work in a reverse direction. That is to say, the chamber 25 which was formerly a suction chamber, now becomes a pressure chamber, while thechamber26 becomes a.

suction chamber, and the direction of Huid flow is reversed.` The pump plungers, which in turn depends upon the amount of eccentricity given the eccentrics 22 and4 23. Since the ,amount of eccentricit of these eccentrics' may be varied to any esired amount and the throwr of the ec-4 eentrics be reversed if desired, it follows that the operator has complete control of the pump through the medium of the hand wheel of Figs. 1 and 3. It never becomes necessary toreverse the direction of rotation of the shaft 24, nor to vary its speed, but it is obvious that the pump could be controlled in that manner ifvso desired.

It will be observed from Figs. 6 'and 7, that the throw or setting of the valve eccentrics is spaced 96 or a quarter revolution from that of the plunger eccentrics, and with this setting the valves will always be in .position prorly to control the fluid diuantity of fluid' pumped depends upon t e stroke of the not opposed by fluid pressure. The reason why this is so, may be seen byV an inspection all open to the discharge chamber B, so also are the correspondin cylinders 9, 10 and 11, of Fig. 7 whereas t 1e cylinders 12, 13 and 14, are in communication with the suction chamber A. If the line of eccentricity of the eccentrics 22 and 23 which coincides with the line `of shifting the eccentrics were at right angles to that shown in Fig. 7,V it will be seen that in order to shift the eccentric,22, the iuid in the cylinders 9, 10 and 11 would have to be forced through the valves and into the discharge chamber B, and if the pump were working against a pressure, this pressure lwould tend to resist the shifting of the eccentric. In order to permit the stroke to be varied by shifting the eccentrics 22 and 23, I have displaced the line of shifting 90 from the line of eccentricity of the valve ec-` centrics 32 and 33, or alon the line b b, of Fig. 7, and by so doing, am enabled to shift the eocentrics and consequently the pistons or plungers connected therewith in a Y direction between the forces set up b Huid ,pressure acting on the istons, and 1n this manner the act of shifting is effect-ed with very httle effort and the force required is substantially that required to overcome the mechanical frictionof the pistons and other parts.

It is true that were the shaft 24 at rest, it would -be possible to have one of the Vpistons in such position that the correspondlng cylinder is cut oif from the chambers A. and B, by its valve. Under this condition therewould be a flu-id lock in that particular cylinder and the shifting eccentrics could not be moved. But it is proposed not to -attemptgto shift the ec entries at such time, but only whenthe sha 24 is rotatin and, in vsuch case the'eccentrics may casi y be shifted throughout their entire range of movement to either side of center or position- 4of zerostroke. 1

The pressure of the pump plungers of each set' on their respective eccentrics may be resolved into two forces acting at different points on the shaft in opposite direcins tions, and hence these .two forces constitute i a colple tending to rotate the shaftend Since, however, the' eccentrics are located very closely\together, the tendency of this couple to bend or distort Athe shaft. v

iii set forthwhat I desire to have 'protected' 460 is found in elevator practice where the maximum torque is required in starting the load. In the case of elevators, a constant speed non-reversing alternating current motor could advantageously be connected to drive the pump shaft, and the pump could be connected to a fluid motor such as shown in Patent N o. 980,449, issued to me on January 3, 1911, for hydraulic engine. The entire control of the elevator would be means of the hand wheel or other isuitable operating mechanism associated, `with the cam 67, such as an electric or hydraulic motor.

The pump may handle any desired Huid such as oil or water, but in general I prefer to use a good grade of oil which is not appreciably affected by changes in temperature. When oil is used, the entire ump mechanism will be amply lubricated Without resorting to oil or grease cups.

By the arran ment of ports and valves herein disclose the pump will operate without churning the fluid, which feature is most desirable, and particularly so when oil is used. The uid is directed between the valves and plunger cylinders through ports or passages which are as short and straight as possib e so as not to agitate the Huid any more than possible and to reduce thefriction losses in said ports and passages.

While I have disclosed a ap embodiment of m invention in which I use two sets of p ungers having seven in a set, it is to be understood that I may use any number of setsand 'of plungers in a set. However, I prefer to use but two sets, and to use an odd number of plungers in a set, since by such use there are never more than two plungers passing throu h the dead center at the same time, and t e torque is more uniform than where an even number of plungers are employed in a single set.

The pump as shown and described is very compact and occupies but small space, while at the same time it has great capacity. The pump is balanced mechanically and also against fluid pressure, and may therefore be operated at comparatively high speeds without vibration.

The p may be used as such, or .it may be as a variable speed reversible lpid motor, noA changes in the apparatus being necessary to convert it into a motor or engine.

Without myself to the precise arrangement andconstruction of parts hereby Letters atent of the United States is 1.- A variable stroke pump, a plurality of cylinders arranged in two sets, ports for the fluid to and from the cylinders, a shaft, pistons in the cylinders, a justable means operatively connecting the pistons 66 of each set of cylinders with said shaft,

valves for the cylinders, l

and means for varylng said adeil'ected by pump 'containing' Aciable time durilg driving means for the valves, justable means in both directions from a center so as to vary the Adirection of ilow and amountof fluid pumped by the pistons, and for obtaining an equal and opposite stress on the shaft during the operation of the pump.

2. In a pump of the variable stroke type, two Vindependent roups of cylinders, pistons in the cylinfers, a drive shaft, independent means for connecting the pistons of each group with the said shaft, means for `varying said connecting means in opposite directions relatively to each other so as to obtain`a variable stroke of all of the pistons, said varying means being arrangedl always to effect equal and opposite stresses on saiddrive shaft for all positions of the said stroke varying means.

3. A pump comprising a plurality cylinders each having a piston therein, a shaft, a center shifting device on the shaft connected with said pistonsand operable to vary the length of piston stroke from zero to a maximum inboth directions, and means to prevent a too sudden reversal of. said center shifting mechanism.

4. A pum comprising a plurality of cylinders eac shaft, a center shifting device on the shaft connected with said .istons and operable to vary the length ci) piston stroke from zero to a maximum inboth directions, and means for maintaining said center shifting device in zero or no stroke position for an ap reciable period of time to prevent a too su den reversal in the fiow dof the Huid pumped.

5. In a pump, the combination of a plurality of cylinders arranged .in two groups, pistons `in vthe cylinders, a drive shaft mechanisni connecting said pistons with the drive shaft and consisting of a'centershifting device having two independent and conjunctively operated parts, one for the pistons of each oup of cylinders, means for controlling sa1d center shifting device and arranged to maintain the same in a position of no stroke'of the pistons for an apprethe operation of reversing the ystroke o the piston'by the center shifting device. i

6. In a variable stroke pump, the combination of a shaft, i; plurality of cylinders radially disposed about said shaft, a piston in each cyhnder, ai center shifting device connecting said pistons and the/drive shaft, a. manually operated device for operating the said center shifting device to vary and 7. A pump comprising a drive shaft, a plurality of cylinders radially disposed about said shaft, pistons for the cylinders, a device connecting said pistons and shaft arranged to eilect a variable length of stroke of the pistons and to reverse the stroke of the pistons, and means for preventing a too sudden movement of said device when-operated to eil'ect a reversal of stroke of the pistons.

.8. A pump comprising a drive shaft, a

Lplurality of cylinders radially disposed about said shaft, pistons for the cylinders, an eccentric on said shaft connected to reciprocate said pistons, means for varying the eccentricity of said eccentric and thereby vary the length of stroke of the pistons connected to the pistons of each group and reverse the Stroke of the latter, and

'means for preventing a too sudden movementv of said eccentric varying means.

9. A pump 'having aplurality of cylinders radially disposed about a sha'ft ,and

arranged in two groups, a piston for each cylinder, a separate eccentric lon the shaft connected to the pistons of each group of pistons, screws for varying the eccentricity of each eccentric and thereby vary 'the length of stroke of the pistons, pinions for 1l. A pump having a plurality of cylinders radially disposed about a shaft and arranged in two groups,` a piston for each cylinder, a separate eccentric on the shaft connected to the pistons of each group of pistons, screws for varying the eccentricity of each eccentric, and thereby vary the length of stroke of the pistons, pinions for operating the screws, a rack for rotating said pinions, andV a manual controlled device for operating said rack.

12. A pump having a plurality of cylinders radially disposed about a shaft and arranged in two groups, a piston for each cylinder, a separate eccentric on the shaft connected to the `pistons of each group of pistons, screws for varying the eccentricity of. each eccentric and thereby vary the length of stroke of the pistons, pinionsfor operating theV screws, a rack for rotating said pinions, and a hand operated worm of low pitch for operating said rack.

13. A pump having a plurality of cylinders radially disposed about a hollow shaft, and arranged in` two groups,' a piston for each. cylinder, a separate eccentric on the shaft connected to reciprocate the pistons of each group of cylinders, screws for varying the eccentricity of said eccentrics and thereby vary the length of stroke of the pistons, pinionsfor operating Asaid screws, and

a rack in saidghollow shaft adapted to ro- 'Y tate said pinions'.

In testimony whereof, I have signed my name to this specification in the presence 0F75 twosubscribing witnesses. l

. AUGUST SUNDH. Witnesses:

Jamas G. Barnum.,

: Wannen C. STxaNe.

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