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Publication numberUS3044403 A
Publication typeGrant
Publication dateJul 17, 1962
Filing dateOct 13, 1958
Priority dateOct 13, 1958
Publication numberUS 3044403 A, US 3044403A, US-A-3044403, US3044403 A, US3044403A
InventorsGeorge T Ronk
Original AssigneeGeorge T Ronk
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Deep well pump and valve
US 3044403 A
Abstract  available in
Images(8)
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Claims  available in
Description  (OCR text may contain errors)

July 17, 1962 Filed OCT.. 13. 1958 FIG;

G. T. RONK 3,044,403

DEEP WELL PUMP AND VALVE 8 Sheets-Sheet 1 INVENTOR.

) orneys July 17, 1962 G. T. RoNK DEEP wELL PUMP AND VALVE 8 Sheets-Sheet 2 Filed Oct. 13. 1958 INVENTOR. Georg@ l' Ban/e 455, LZ orneys July 17, 1962 G. T. RONK DEEP WELL PUMP AND VALVE 8 Sheets-Sheet 3 Filed OCT.. l5. 1958 INVENToR. George 2T Bonk BY fornezls July 17, 1962 G. T. RoNK DEEP wELL PUMP AND vALvE 8 Sheets-Sheet 4 Filed Oct. 15. 1958 IN VEN TOR. 'aozzg I Bonk BY n? orny July 17, 1962 G. T. RONK DEEP WELL PUMP AND VALVE 8 Sheets-Shet 5 Filed OCT.. 13. 1958 July 17, 1962 G. T. RONK 3,044,403

DEEP WELL PUMP AND VALVE Filed Oct. 13. 195B l v 8 Sheets-Sheet 6 FIGO INVENTOR.

'eorge l' Pani( G. T. RONK DEEP WELL PUMP AND VALVE July 17z 1962 8 Sheets-Sheet 7 Filed Oct. 13. 1958 FIG., 10

INVENToR. George wzk @MBV Mm,

mwa() Y M z'0rney5 BY d? July 17, 1962 G. T. RONK DEEP WELL PUMP AND VALVE Filed oet. 15. 1958 158 EFG. jj l (QM 29,7 Y

it States This invention relates to a well pump apparatus, and more particularly, to a control mechanism for the remote control of a working valve in the plunger of a pump.

A pump widely used in oil-well operations or in the pumping of other volatile or ebullient liquids from wells comprises a cylindrical tube or working barrel which is suspended at one end from the well casing head with the other end immersed in the fluid in the well. A pumping cylinder or plunger is movably mounted in the working barrel and is given a reciprocable movement by means of a column of actuating or sucker rods suspended from the end of a powered walking beam or other similar mechanisms. These sticker rods are inside the working barrel and extend from the surface of the ground to the plunger or pumping cylinder disposed near the bottom of the working barrel. A standing or stationary valve is mounted in the lower end of the working barrel and a working or traveling valve is mounted in the plunger.

In use, on the down stroke of the walking beam, or as the plunger is moved downward in the working barrel, the working or traveling valve in the plunger opens to allow liquid in the working barrel to move through the descending plunger at the same time the standing or stationary valve is closed to prevent the movement of the plunger from forcing the liquid out of the bottom of the working barrel. On the up-stroke of the walking beam, this working or traveling valve must be closed so that the upward movement of the plunger causes a suction which opens the standing valve and which draws additional liquid inside the working barrel. In addition, this movement lifts the oil inside the plunger. As this process is repeated, more and more liquid is drawn into the working barrel until it for-ms a column discharging out of the top of the working barrel into a container. It is apparent that proper operation of the pumping device requires the working valve to be closed as the plunger is raised, and opened as the plunger is lowered.

Typically, the working or traveling Valve is simply an upward opening ball and seat, although other valve shapes may be used, such as the plumb bob. When this pumping mechanism is used for raising water or other nonvolatile liquids, the above-described valves are satisfactory since the weight of the ball plus the weight of the liquid above it will seat the ball at the proper time. However, when'rthis mechanism is used to hoist volatile or ebullient liquids such as acids or gas-impregnated oils, which are encountered in an oil-well pumping operation, there is no certainty that the force of gravity acting on the working valve will be effective to seat the valve. This is because an accumulation of gas in the well may produce an upward pressure lifting this ball valve oi its seat, and thus rendering the working valve ineffective in maintaining and producing a vacuum between the bottom of the plunger or hoisting cylinder and the standing valve at the lower end of the working barrel.

The solution of this problem Ais ditlicult because it requires some means for positively closing the working or traveling valve when the pumping cylinder is hundreds of feet below the surface of the ground. It is important to note that if the traveling valve can be closed mechanically on the upstroke, then the presence of gas pockets in sections of the rising column of liquids is not much of a problem since the rising liquid plus the gas pockets in the working barrel form a unitary column which is ele-V vated by stages to the point of discharge.

Different mechanical means have been tried to control this traveling valve so that it opens promptly on the down stroke and closes promptly on the up stroke. One partially successful means for controlling the closing of this traveling valve has been by the installation of a discharge valve in the Working barrel well above the plunger or cylinder. This discharge valve is operated by a diaphragm and is designed to be closed except when there is suicient hydraulic pressure in the rising column of fluid to lift the diaphragm. When the diaphragm is lifted, the discharge valve opens to allow fluid to pass out of the working barrel and into a container. The diaphragm can be adjusted so it operates only when the pressure in the space between the discharge valve and the traveling valve is greater than the maximum upward thrust of gas pressure likely to be encountered during the pump up stroke. In this way, it can be seen that gas disturbances affecting the working valve may be avoided.

This method has certain objectional features. For one thing, the use of the diaphragm-operated discharge valve at the upper end of the rising column of iiuid continuously compresses the rising fluid column so that in the case of volatile oils, the gas content will be affected, either by a reduction of its gas content and the consequent freeing of large amounts of gas or by causing the liquid to be more fully impregnated with gas. In either case, the continuous motion of gas into or out of the liquid produces a turbulence and consequently an emulsilication of the oil which is harmful to the quality of the volatile oils being discharged.

Another harmful effect in continuously using this pressure to close the Working valve in the plunger, is that the diaphragm-operated discharge Valve characteristically operates through a very small initial or final opening, and this causes a further high pressure turbulence which produces increased emulsication. This is commonly known as cutting the oil, and it requires an additional and expensive treatment of the oil in special tanks before it can be used in pipeline transport.

In addition, .another bad effect resulting `from the use of the diaphragm-operated discharge valve is that the minimum pressure required between the dischargev valve and the working valve for its effective operation, greatly limits the amount of volatile fluid which can be drawn from the formation below. It is evident that a sudden drop in the gas pressure below the working valve might causethe discharge valve to always remain closed, so that no uid can move through the working barrel. Thus, while the .diaphragm-controlled discharge valve will partially overcome some defects connected with the operation of the working valve, there is no assurance that the conditions existing in any particular well can maintain a pressure steady enough to provide for economical production. Furthermore, the diaphragm-controlled `discharge valve must be frequently `adjusted to provide for economical operation ofthe pump, and these adjustments, up to now, had to -be done by guesswork.

In this invention, the substantially incompressible properties of these liquids are utilized to form an instant but temporary compressed hydraulic column of -this liquid in the working barrel. This hydraulic column acts like ra ram rod and bears down on the Working valve to close it, just when the hoisting cylinder or plunger begins its upstroke. Then this hydraulic column is quickly suspended, relieving the compression formed when the Working rvalve is closed. This is done 'by providing means for operating an instant wide-open valve, whereby the fluids being elevated may be discharged without excessive interruption of production or a prolonged deleterious compression of the liquid.

What is needed, therefore, and comprises the principal object of this invention is a control mechanism for positively closing a working valve in the plunger of an oilwell pump just las the plunger begins its upstroke, so that variati-ons in pressure in the oil well below the plunger will not unseat the valve and cause 1a prolonged interruption of the flow of oil. Y

A further object of this invention is to provide a control mechanism which may be readily -adjusted to positively close the working valve in -an oil-well pumping plunger for a predetermined number of pump upstrokes.

Yet 'another object of this invention is to provide a discharge valve =for the working barrel of an oil-well pump which Vcloses during the pump upstroke and causes the oil in the Working barrel to form a hydraulic column for positively closing the Working valve in the plunger.

Yet another object of this invention is to provide a control mechanism which provides a hydraulic column for intermittently closing the working valve of a pumping plunger for yany predetermined number of pump strokes and which then dissipates this hydraulic column.

Another object of this invention is to provide a discharge valve in the working barrel of an Voil-well pump having means for advancing the closing of the discharge valve on the pump downstroke, `and retarding the opening of the discharge valve on the pump upstroke to -adjust the compaction of -a hydraulic fluid column formed in the 'working barrel.

Yet a further object of this invention is to provide means for automatically synchronizing the operation of a'valve with the strokes of the pump.

A further object of this inventionis to provide a valve control mechanism with a manual interrupting device tor holding a pump-operated discharge valve closed for one or moreV strokes of the pump so that a solid hydraulic column of fluid may be formed in the Working barrel of the oil-well pump.

Yet`a further object of this invention is to provide a snap-action mechanism at the upper and lower limits of the strokes of a discharge valve linkage mechanism Ato insure a positive opening and shutting of the discharge valve.

These and other objects of this invention will become more yapparentV when read in the light of thewaccompanying drawings and speciiication, wherein- FIG. 1 is an elevational and sectional view showing the oil well, the pump, and the discharge valve in operative lassociation with each other;

FIG. 2 is a side elevational view of the working barrel with the pumping plunger or hoisting cylinder mounted inside;

FIG. 3 is a perspective view of the housing for'the disch-arge valve and showing a part of the connection between the discharge Afvalve and the well pump;

lFIG. 4 is a plan view ofthe discharge valve and timing mech-anism with the housing cover removed;

FIG. 5 is a perspective view of the discharge valve timing mechanismfinV the housing and showing in particular the timing Adisk and part of the lever system which operates the discharge valve;

FIG. 6 is another perspective view of the discharge valve-controlling mechanism which is directed toward a part off the housing showing the mechanism for makingthe disch-arge 'valve snap open and snap closed;

PKG. 7 is a sectional view taken on the line 7-7 of FIG. 4 and looking in the `direction indicated;

FIG. 8 is a sectional view taken on the line 8-8 ofl FIG. 4 and looking in theV direction indicated;

FIG. 9 is a sectional view taken on the'line't-S! of FIG. 4 and looking `in the direction indicated, showing inparticula-r, in dotted lines, the movements orf the lever mechanism for causing the disch-arge valve to snap open and tosnap shut;

FIG. l() is a sectional View taken on the line 10-10 of FIG. 7 and-looking in the direction indicated;

FIG. ll is la sectional view taken on the line 11--11 of FIG. -4 and looking in the direction indicated;

FIG. l2 is `a developed viewr of the `timing disk, showing the lever pawl for preventing the timing disk from coasting or rotating beyond a, predetermined angle during each oscillation of the well pump, in operative engagement with it;

FIG. 13 is a developed view similar to FIG. 12, showing the timing disk with the `lever pawl for preventing coasting movement out of engagement with it; and

FIG. 14 Ais a perspective view of one of the cam track blocks which, when mounted on the timing disk, controls the opening and closing of the discharge valve.

Referring now to FIG. l of the drawings, a Well 10, which in this'case happens to be an oil Well, is sunk into the ground to a depth sufiicient to reach the oil. The well is cylindrical and its periphery is formed by a cement casing 12. A cylindrical working barrel 14, substantially concentric with the casing 12, is suspended from the casing head and its lower end 16 is immersed in the oil 17. A pumping plunger or hoisting cylinder 18 is movably mounted inside the working barrel and a column or string of sucker rods 20 inside the Working barrel is connected at its upper end to the end ofthe Walking beam 22 of the well pump 21. At its lower end, the string of sucker rods is connected to the plunger at cylinder 18, see FIG. 2. The walking beam 22 rocks in a manner well known in the art, and this movement causes the sucker rods 20 and the piunger 18 to oscillate up and down inthe Working barrel 14.- A gas anchor 26 is secured to the end 16 of the working barrel by any conventional means, and operates to restrict the admission of gas therein in a manner well known in the art.

A working or traveling valve 28 comprising a ball and a seat in a cage Si?, is mounted in the plunger 18. As seen in FIG. 2, the traveling valve happens to be mounted at the lower end of plunger 18, but the position of this valve in the plunger is not critical and the traveling valve could be, andfrequently is, mounted in the upper end of the plunger. In addition, a stationary standing valve '32 is mounted in the lower end 16 of the working barrel 14.

This valve issimilar to the working valve 28 in that it comprises a ball and seat in a cage 34, see FIG. 2. Y

In operation, as the walking beam moves downwardly,

e the plunger 18 is Vforced down further into the working barrel. VIn addition, when the stationary valve 32 closes oit the bottom of the working barrel, the continued downward movement of the plunger increases the pressure in region 36. ThisV pressure increase in the oil causes the traveling valve 23 to moveto its open dotted line position, and permits the oil in region 36 to ow around the descending valve 28 into the plunger 1-8. If the plunger is already lled with oil, the oil in the plunger is forced up through the plunger and out opening 19 into the Working barrel.

On the up stroke, when the end of thewalking beam 22 rises and lifts the plunger '18 up in the Working barrel 14, the weight of the oil in the plunger bears against the traveling ball valve 28 and, if` conditions are right, causes it to` close. rlhe continued upward movement of plunger 18 creates a vacuum in region 36'which raises the stationery valve 32 off its seat and sucks oil into the Working barrel 14 from the pool around its lower end. In addition, since the traveling valve 28 is closed, the oil locked inside the plunger is moved upwards with the plunger. This operation continues until the working barrel is completely full of oil. Thereafterz each upward stroke of the.

plunger causes oil to move out of the top of the working barrel and into a container.

It is apparent that if the traveling valves does not seat during the pump upstroke, i.e., when the plunger moves up in the working barrel, then no suction will form in region 36. Instead, the oil in the plunger 18 above the region 36 or in the working barrel 14 will flow downward and move around the open traveling ball valve 28 into region 36, so that the elevating pump strokes will be ineffective.

As stated above, however, the presence of gas escaping from the oil (the oil is always saturated with it) may cause a pressure rise in region 36 which is high enough to force the traveling ball valve 2.8 off its seat so the pump 21 will not function.

Oil is substantially incompressible, and if the upper end of the working barrel outlet is closed off just as the plunger 13 begins its upstroke, then the `liquid in the working barrel will form a temporary compressed hydraulic column of oil. It has been found that this column of oil behaves like a ramrod, and acting against the traveling ball valve 28, forces it to seat. r{his suggests that a discharge valve be installed in the oil line at the top 'of the well and that a. suitable control mechanism, indicated generally by the `reference numeral 4), be provided, see FIG. l. To produce the above-described hydraulic column and to force the traveling valve 2&5 to seat, the control mechanism 46 must cause the discharge valve to close just as the plunger 18 begins its upstroke. After the traveling valve is closed, then the discharge valve must be opened promptly to permit the oil to be discharged from the well and to minimize the harmful effects of prolonged oil compression.

The conditions which cause gas in the well to unseat the traveling valve occur at random but frequent intervals, depending upon the conditions in the particular Well. Futhermore, any compression of the oil, as in the formation of the hydraulic column, may adversely affect the quality of the oil, so that it is desirable that the frequency of the formation of the hydraulic column be kept to a minimum. As stated above, the occurrence of the high gas pressure which may unseat the traveling valve occurs at random intervals, so that it is necessary only to make use of a device which operates at predetermined intervals in a sequence of operations to close the discharge valve and form a hydraulic column. For this reason, the control mechanism attached to the discharge valve must provide a convenient means for regulating 'the operation of the discharge valve, and hence the frequency of formation of the hydraulic column, in accordance with conditions at the particular well.

The discharge valve and control mechanism 40 is mounted inside of a protective housing 44;, see FIG. 3. A cover 46 is pivotally connected to the top of the housing, and a latch 48 is provided so that the housing may be locked to prevent tampering by unauthorized persons.

The power for actuating the mechanism 40 comes from the movement of the Walking beam 22, although this is not a necessary arrangement, and a separate power source can be employed. As seen in FIGS. l and 3, a leg 50` is rigidly secured by any `conventional means 52 to one of the rods 2li suspended from the walking beam 22 so that the periodic rocking movements of the walking beam cause the leg 50 to move up and down in synchronization with it. The leg is provided with an integral and perpendicular foot 54 for reasons to be described below.

As seen in FIGS. 6 and 7, an interior housing 56 for preventing the entry of dirt inside the housing, is rigidly secured to the inner surface of a slotted wall 58. This housing has vertical side walls and inwardly converging top and bottom walls. A horizontal drive shaft is rotatably mounted in bearings 62 on the opposed vertical sides of housing 56.

A sleeve or collar 6i, see FIG. 7, is centrally mounted on shaft 60. Attached to this collar are radially extending upper and lower members 66 and 68. These lever members may be said to define a common plane and they are at an acute angle with respect to each other. rthe ends of the lever members 66 and 68 may extend through the slot or opening 78 in the wall 58 and project outside of the housing 44, depending on the rotative position of the shaft 6u, see FIGS. 3 and 7.

A reinforcing plate 72, see FIG. 3, having a vertical centrally disposed slot 74, is rigidly secured to the outer surface of wall 58. The slot 74 is aligned with slot 70 and with the plane of rotation of the lever members 66 and 68. Furthermore, slot 'i4 is wide enough to permit the lever members to extend through them and into the path of the moving foot S4.

In operation to this point, it can be seen that the reciprocating vertical movements of the leg 50 and foot 54 cause the foot to engage the end of one of the levers 66 or 63, depending upon the position of shaft 623. In particular, as seen in FIG. 7, if the leg Sti is moving upward, the foot 54 engaging lever `66 drives it upward to the dotted line position and causes shaft 66 to rotate. In this position, the tip of the lever 66 has entered the slot 74 and has moved out of engagement with the rising foot 54. At the same time, the rotation of shaft 6i? causes lever 68 to move into the dotted line position where its end projects through the slot 74 in the reinforcing plate '72 and into the path of the foot 54.

As the walking beam moves downwardly, carrying the leg 50 and foot 54 along with it, the engagement of foot 54 with the top edge of the end of lever 63 forces lever 68 to pivot back into the slot 74 where it is out of engagement with foot S4, after which the foot 54 continues its downward movement to the bottom of the pump stroke. At the same time, the rotative movement of shaft 66 in the opposite direction` to that described above, causes lever 66 to move back into operative position. It is apparent that the movement of the pump strokes through leg 5i) causes shaft 66 to rotatively oscillate on its axis through a predetermined angle in synchronization with the pump 21.

As seen in FIGS. 7 and 8, levers 66 and 68 are mounted to pivot at 77 and 77 on the lever stem portions 67 and 69 which are rigidly secured to the collar 61 on shaft 60. The pivotal connections are such as to permit each lever to freely pivot only toward each other, as shown in dotted lines in FIG. 7, so that a force exerted on the levers in this direction causes the levers to pivot without rotating the shaft 60, while forces exerted on the levers in the opposite directions cause the shaft to rotate. Coil springs 80 and 82 are mounted on pivots i7 and 77 to cause levers 66 and 68 to automatically return to their straightline position if they should be bent. This arrangement constitutes an automatic aligning device for the actuating levers 66 and 68.

Without this structure, it can be seen that if the apparatus were connected to the pump 2'1 so the top edge of lever 66 was engaged by foot 54 as the leg was moving downward, instead of upward, `the resulting clockwise rotation of shaft 60 would drive lever 68 into a destructive engagement with the lower wall of the protective housing 56. A similar thing could happen on the upward movement of the leg 5t). Because of this self-aligning mechanism, in a similar situation, the descending foot 5d would first cause the lever 68 to move into abutting engagement with the lower converging surface of the housing. Thereafter, any further force exerted on either of the levers would cause lever 66 to pivot in the counter-clockwise direction, as indicated in the dotted lines in FIG. 7, without producing any rotation in shaft 6l). This pivoting movement permits the outer portion of lever 66 to move into slot 74 so the foot can move by it on its continued downward motion. After the foot 54 passes by lever 66 and starts its upstroke, the coil spring 86 would have caused lever 66 to pivot back to its initial operative position where it is again in the travel path of foot 54 so that as the foot 54 moves upwardly it would engage lever 66 7 Vand would pivot it into the slot 74 and rotate the shaft 60. Thereafter, it can be seen that the movement of levers 66 and 68 would be in proper synchronization and alignment with the motion of leg 50 and foot 54. Another important feature resulting from this automatic aligning mechanism is that the actuating levers 66 and 68 can be removed and replaced without any necessity forV stopping the pump 21.

An additional collar 76, see FIGS. 5, 6 and 7, is rigidly secured to shaft 60. Integral with this collar is a driving or actuating lever arm 78. Since the shaft 68 is oscillating on its axis, it is evident that the driving arm 78 will also oscillate in an arcuate path between the solid line and dotted line positions shown in FIG. 7.

A vertical support 81,V which may comprise a cylindrical sleeve, is rigidly mounted on the bottom of the housing 44 by any conventional means, such as welding. A shaft 83 is rotatably mounted inside the sleeve, see FIGS. 5

and 7. The top of the shaft 82 is slotted at 84 and the Y width of the slot is substantially equal to the width of a lever 86 which is positioned in the slot 84 for pivotal movement, see FIGS. 6 and 7. As seen, a pivot bolt 88 extends through slot 84 and `through the central portion of lever 86 to pivotally retain it on the shaft 82.

. The lever 86 is elongated and has oppositely extending arms 90 and 92, see FIGS. 4 and 7. Arm '90 is long enough to be in the path of the end of the oscillating actuating lever arm '78, depending on the rotative position of the shaft 83 in the sleeve or support 81.

. As seen in FIG. 6, an arm 94 is rigidly secured to shaft 83 and extends outward in a radial direction. The outer end of this arm is pivotallyV connected to the end of a horizontally disposed, reciprocably mounted push rod 96. This push rod isV mounted vfor limited movement in a horizontal direction, and it is apparent that its connection to lever 94 would cause shaft 83 to rotate. This rotation of shaft A83 can move arm 90 of lever 86 to the dotted line position shown in FIG. 4, which is out of the path of the oscillating actuating arm 78, as described more fully below.

The arm 92 of lever 86 is in engagement with arm 98 of lever 100, see FIG. 5. Lever 100 is adapted to be rigidly connected to a shaft 102 so that any rotation of the lever 100 causes the shaft 102 to rotate. This shaft operates a discharge valve 104 which controls the passage of oil inline 42, see FIG. 7. The llinkage inside the inner Ihousing 101 connecting shaft 102 with the valve 104 may be entirely conventional, the only requirement being that in one rotative position of the shaft 102, the valve 104 is open, andin another rotative position the'valve is closed. Furthermore, the valve should be a kind which opens and closes very rapidly to prevent turbulence vvhich'would produce harmful emulsications. In this particular embodiment, when arm` 98 of lever 100 is down, as shown in FIG. l0, the valve 104 will be closed, and when arm 98 is up, as shown in the dotted lines in FIG. 7, the valve will be open.

The lever 100 includes an arm 106 which is opposite to arm 98. A coil spring 108, see FIG. l0, is connected 'between arm 106 and the ibase of the housing. This coil spring acts to bias lever 100 and exerts a rotative force on it in a direction which causes discharge valve 104 to move to an open position.

In operation to this point, when lever 86 is positioned so arm 90 is in the path of the oscillating actuating lever 78, as the actuating lever 7 8 moves upward from the dotted line position to the solid line position as shown in FIG. 7, it Will engage the lower edge of arm 90 and force lever 86 to pivot from its dotted line position tothe solid line position. 'Ihis movement will depress arm 92 and since arm 92 is in engagement with the upper edge of arm 98 of lever 100, arm'98 will also be forced down Y from arm 90, the tension in Vcoil spring 108 would cause lever to immediately rotate in a clockwise direction and immediately open discharge valve 104. This is not desirable, as described below, and means are necessary to hold the discharge valve closed for a predetermined minimum period, usually less than the period of a pump stroke, once the discharge valve is closed.'

lt is apparent that if arm 90 were not rotated or moved out of contact or engagement with the actuating arm 78, the boss 79' on the end of the actuating lever arm 78, see FIGS. 6 and 7, -Would engage the arm 90 on every pump stroke. This would cause the discharge valve 104 to close on every down stroke of the walking beam or pump rods and, as described below, open for a portion of every up stroke. ln the interval between this regular opening and closing, While the leg 50 and foot 54 is traveling above the mechanism 40 out of contact with the levers 66 and 68 in the box 44, the discharge valve 104 would be open so the oil would continuously flow out of the Well. This would continue until the flow was cut olf'when the leg 50 and foot S4 moved toward the bottorn of the next stroke. Since the bottom of the pump stroke and the low point of foot v54 may be a considerable distance fbelow the position of lever 68, the interruption of the flow of oil would be maintained until the movement of the plunger 18 and the rise of the walking beam had moved back this distance, and this interruption for this period of time causes the hydraulic column between the outlet of the well and the plunger inside to eifectively close or seat valve 28 lby means of the ram rod action described above. As stated above, however, the formation of the hydraulic column at such frequent intervals and the consequent frequent compression of the oil might be unnecessary for the conditions in the Well and it could be harmful to the oil. For this reason, a timing device for controlling the frequency of the formation `of the hydraulic column is necessary.

As seen in FIG. 10 of the drawings, push rod 96 is movably mounted in a bearing member 110, and a 'coil spring 112 positioned between a side of bearing member and an otset cam-riding portion 114 of the push rod exerts a ibiasing force on the push rod which tends to move it in a direction away from support 80. This movement rotates lever 86 so its arm 90 is in the path of the actuating lever 78, see FIG. 4. With this arrangement, it is apparent that the control of the position of the push nod 96 can 'be used to control the position of the lever 86 with respect to the oscillating actuating lever 78, and hence it can be used to control the operation of the discharge valve 104.

To provide the necessary control for the push rod 96, a timing disk 116, which functions like a ratchet wheel, is mounted for rotation on a shaft 117 secured to a Wall 118 of theV housing 44, see FIGS. 4 and 8. A collar 120 is rigidly mounted on the end of shaft 60 remote from collar 76. This collar is provided with an integrally attached lever arm 122. Since shaft 60 is oseillating, the lever ann 122 will also oscillate between the solidand dotted line positions shown in FIG. 8.

A spider 124 having angularly spaced radially projecting arms 126 and 128 is rotatably mounted on shaft 117. Arm 126 is pivotally connected to 4the free end of arm 122 by any conventional means, as seen in FIG. 8. A pawl 130 is pivotally mounted on the end of arm 128 and this pawl is biased into engagement with one of the twelve teeth on the ratchet Wheel timing disk 116 by means of a pawl spring 131. The teeth of the timing disk are shaped so that each oscillation of shaft 60 and the consequent oscillation of spider 124, rotates the timing disk 116 in a counter-clockwise direction, as seen in FIG. 8, and through an angular distance equal to the arc length subtended by one tooth on the periphery of the timing disk. Since the timing disk has twelve teeth in this particular embodiment (timing disks with a different number of teeth are contemplated), it is apparent that twelve oscillations of shaft 60, or twelve strokes of the Well pump, are required to rotate the timing disk through one complete revolution.

To prevent the timing disk 116 from rotating backward with spider 124, a spring-operated bolt lock 134, see FIG. 5, will coast over the inclined portion of teeth 132 on the forward motion of the timing `disk (clockwise, as seen in FIG. but any movement of the disk in a reverse direction `will cause the 1bolt lock 134 to abut against one of the radial walls 133 of teeth 132, as seen in FIGS. 5 and 8.

The timing disk 116 has opposed parallel surfaces 136 and 138. Surface 136 is machined to provide twelve uniformly and angular-ly spaced triangular spacing members 140, see FIGS. 5 and l1. The adjacent sides of these triangular spacing members are parallel to each other. Centrally disposed in the space between the sides of the adjacent spacing members 140 are threaded bolt openings.

A plurality of cam track blocks 144 `are provided. Each block has opposed parallel surfaces 150 and 151, see lFIG. ll. The sides 153 of the block, see FIG. 14, are generally parallel to each other and the spacing between them is substantially equal to the spacing between the adjacent sides of the spacers 140 to permit the blocks to be snugly mounted between them, see FIG. 5. The thickness of these blocks is substantially equal to the thickness of the spacers, although this is not critical.

Each block is provided with a cam surface or an inclined ramp 148 at one end of the block which extends in a direction substantially parallel to the end of the block. One end of the rarnp is at the side of the block at surface 151 and the other end is at surface 150, centrally between the sides.

The blocks are further provided with a bolt-receiving opening 145 for receiving a locking bolt 146. The locking bol-t is adapted to extend through the opening 145 and into threaded engagement with threaded openings in the timing disk, so that the block can be mounted on the timing disk. As seen, the bolt-receiving opening 145 is nearer one end of the block than the other. This is important because it permits block 145 to be mounted in three operative positions on the timing disk, i.e., with ramp 148 inward toward the axis of the timing disk, and with surface 151 or 150 bearing against surface 136 of the timing disk 116, see block 144 in FIG. 1l, and the block immediately to the right of it. Alternatively, the :block could be mounted with ramp 148 away from the axis of the disk, see the block lto the left of block 144 in FIG. ll. When the ramp is away from the axis of the timing disk, the block Willbe positioned out of the way of the push rod 96, as described below.

The cam track blocks 144 are shaped so that if they are mounted with cam surface 148 facing inwardly and with surface 151 engaging the timing disk surface 136, see block I144 in FIG. 1l, 'then lche cam surface or ramp 148 will be positioned so that as the timing disk is moved around its axis the cam-riding portion 114 of push rod 96 Will ride up on surface 148 to surface 150. This Will displace push rod 96 to the left as seen in FIG. 6, and cause it to rotate lever '86 to the dotted line position shown in FIG. 4, so that the gdischarge valve 104 will be held open for that pump stroke by the action of spring 108.

AIf it is desired to maintain the discharge valve 104 in its open position yfor a number of pump strokes, eg., five, for example, then five cam track blocks would be mounted on lthe timing disk 116 with their cam track 148 in -an inner position, see FIG. 1l. Of these cam track blocks, only cam track block `144 is positioned with its surface 150 remote Afrom the surface 136 of the timing disk. All Ithe other cam track blocks 144 seen to the right of cam track block 144 are positioned with their surface 150 engaging or facing surface 136 of the timing disk, and with their surface 151 remote from it. This arrangement is important because if all ve blocks Were mounted the same Way as block 144', the cam-riding portion 114 of push rod 96 riding on the ramp 148, would jump in and out between the outer surface of the block `and the surface of the disk as it moved from the end of one block to the ramp 148 of the next block 144.

By positioning the four blocks to the right of block 144 so surface 151 is remote from the timing disk, the cam track blocks form a single unitary and continuous cam track. This arrangement permits the cam-riding portion 114 to ride smoothly up ramp 148 on block 144' to surface 150, as the timing disk rotates. Then, as the disk continues to rotate, this cam-riding portion moves to -the nex-t blocks on ltheir surfaces 151.

It is noted that a portion of the sides of the block converge slightly at 152, see FIGS. 111 and `14. This eliminates Lany disturbing discontinuities in the cam track formed by the intersection of the sides of the block, and it permits the cam-riding portion 114 to easily and smoothly pass from one block to another.

The remaining blocks 144 on disk 116 are positioned so the ramp 148 faces outwardly. In this position, no part of these blocks can engage the cam-riding portion 114, so when the disk rotates so that the first of these blocks 144, see FIG. ll, approaches the cam-riding portion 114 riding on surface 151 of the cam track, the cam-riding portion will leave the cam track and will engage surface 136 of the timing disk, because of the bias exerted by spring 112. This movement of the push rod 96 rotates lever 86 so that its arm 90 will be periodically engaged by lever arm 78. In this way, the discharge valve 164 will close for each successive stroke of the pump, while these blocks 144" pass by the camriding portion.

It is apparent that the timing disk and cam track block-s provide a. means for regulating the operation of the discharge valve so it closes and opens at every pump stroke, or closes or opens for any predetermined number of consecutive pump strokes, limited by the number of teeth of the periphery of the timing disk.

The linkage between the walking beam 22 and the leg 56, and the linkage between the connected levers in the control mechanism 4t), is rather long, and considerable play may exist between them, particularly after a period of use. This play could affect the precision of the rotation of timing disk 116 and consequently the operation of valve 164 could be adversely affected. To avoid this possibility, a snap-action mechanism has been provided to assure that the levers 66 and 68 and shaft 60 will snap up and down between the solid and do-t-ted line positions sho-wn in FIG. 7. In addition, this mechanism assures a completely uniform ratchet cycle for the timing disk 116 and the associated levers connected to shaft 60 will lhave a snap ending to their strokes.

As seen in FIGS. 6 and 9, this snap-action mechanism comprises -a collar 154 rigidly secured to shaft 60 adjacent collar 76. A lever arm 156 is rigidly secured to this shaft. Since shaft 6@ is oscillating, it is apparent that lever arm 156 will also oscillate between the solid and dotted line positions shown in FIG. 9. The rotative movements of lever arm -'156 will be in a plane parallel tothe inner surface of wall 158 of the housing 44.

A coil spring 16@ is connected between the free end 157 of lever arm 156 and the free end 161 of another lever 162. Lever 162 is pivotally mounted on wall 15S at pivot 164, and is held close to the inner surface of Wall 153 by means of a U-shaped member 166, see FIG. 6. The legs of this member act as abutments to limit the pivotal f eedom of lever 162. These limits are shown in the soid and dotted line positions of lever 162 in FIG. 9.

It is evident, as seen in FIG. 9, that the coil spring at the opposite ends of the cycle of the levers 156 and 162 is substantially horizontal and the separation of the free ends 157 and 161 of the levers when the shaft 66 is at the extreme ends of its angular displacement is less than the separation of the -free ends when the oscillating shaft 60 is moving through intermediate portions of the cycle.

In operation, las shaft 60 rotates in a counter-clockwise direction (as seen in FIG. 9),-the resulting movement of lever arm 156 increases the space between the free ends 157 and 161 of the" levers 156 and 162. This stretches the coil spring 160 and puts it under tension. Then, as the free end 157 of lever arm 156 continues to move downwardly, the force exerted on the free end 161 of lever 162 by the tension in spring 160l causes lever 162 to rotate on pivot 164 (in a clockwise direction) and causes its free end to move downward. While this is happening, the tension in the spring 160 keeps increasing because the spacing between the free ends of lever 156 and 162 continues to increase. Finally, the separation Vof the free ends 157 and 161 of the levers reach their point of maximum separation. Thereafter, as the free endsV of the levers continue their downward movement,

`the spacing Vbetween them begins to decrease and the tension in the spring provides an Vadditional force which accelerates the rotative movement of levers 156 and 162 and provides a positive snap to the end of their movement. This snap action is repeated as the direction of rotation of levers 156 and 162 reverses and they approach their upper limit. In this way, cycles of the mechanism 40 will be substantially uniform despite any play which may exist between the attached parts. Y

The free end 157 of lever 156 has another function, as described below. The creation of the above described hydraulic column requires the discharge valve 104 to be closed lfor a predetermined period Vin order for it to be effective in closing the traveling valve 28. Since arm 106 of lever 100 is connected to coil spring 108, the lever 100, and consequently discharge valve 104, is spring urged into an' open position. VWith this arrangement, after the actuating lever 7S, driven by the descending foot 54, closes the discharge valve through the linkage mechanism connecting them, the action of spring 108 would immediately begin to openV the valve, and since the valve 104 is designed to open rapidly, this action would destroy or prevent the formation of the hydraulic column before it can become effective in closing the traveling valve 28. To prevent this from happening, a mechanism must be provided to hold the discharge valve 104 closed for a predetermined period after itV is once closed.

This mechanism, as seen in FIGS. 9 and l0, comprises a horizontal tube 167 secured oy any conventional means to the inner surface of wall 158 of housing 44. 'Ihe tube is rectangular in cross section'and a rod 168, also rectangular in cross section, is movably mounted therein. A coil spring 170 is mounted inside the tube 167 and biases the rod 168 toward the mouth of the tube. The bottom of the tube is slotted and a depending projection 172 integrally secured to rod 168 extends through the slot. 'I'he outer end 174 of rod 168 is planar and is inclined upwardly toward wall 158 to provide a cam surface.

In operationV to this point, as the end of the actuating lever 78 is rotated upwardly, Vthe linkage mechanism actuated by it causes lever arm 98 of lever 100 to descend, see FlG. 7. In descending the end of leverarrn 98 rst engages cam surface 174 and, overcoming the resistance of spring 170, forces rod 168 inside ofthe tube 167, see FIG. 10. Once lever arm 98,moves below the edge 175 of this cam surface on rod 168, the rod'168 is moved 'outwardly from tube 167 under the action of spring 170. Then, when actuating lever arm 78 is no longer driven by the foot 54, Ylever 100, urged by spring 108, will attempt to rotate in a clockwise direction (as seen in FIG. l). When this happens, lever arm 98 will Y engage the edgeV 17S of cam surface 174, and this engagement will prevent any clockwise rotation by lever 100 so that the discharge valve 104fwill remain closed.

In order to release lever A104) after the discharge valve rotatably mounted in bearings-178, see FIG. 9. An arm 180 is rigidly secured to one end of the shaft and this arm is adapted to be engaged by the free end 157 of lever arm 156 as it rotates downwardly, driven by shaft 60, see FIG. 4. Y

As seen in FIGS. 9 and l0, an additional lever arm 182 is rigidly formed on shaft 176, and this arm is positioned for engagement with the depending projection 172. With this arrangement, as lever arm 156 swings downwardly, it engages arm 180, causing shaft 176 to rotate. This rotation causes lever arm 182 to press against depending projection 1'72 and forces rod 163 back inside tube 167 against the action of spring 170. This permits spring 108 to pivot lever so lever arm 98 moves past the rod 168 and opens the discharge valve104.

It is noted that lever arms 78 and 156 are substantially parallel to each other, see FIG. 6. Furthermore, the discharge valve is closed, depending on the position of the cam track blocks 144 on timing disk 116, only when the tip 79 of actuating lever 78 is at its highest point of its oscillation. The result is that once the discharge valve is closed, it will remain closed until shaft 60 rotates through an angle which causes lever arm 156 to engage lever arm 180 as described. The period of time the discharge valve remains closed, and consequently the duration of the hydraulic column, principally depends on the period of oscillation of shaft 60. It is apparent that by varying this, or the arc length between tip 157 of lever arm 156 and lever arm 130, the duration of the hydraulic column may be controlled.

It occasionally happens that the hydraulic column formed by the closing of the discharge valve 104is spongy due to the presence of emulsied material so that the working valve 28 may not be closed by the hydraulic column. In that case it may be desirable for the pumper, when servicing the well, -to leave the discharge valve closed through the cycles of one or more strokes of the oil-well pump to compress the emulsied spongy material so it can force the working or traveling valve 28 to close.

To do this, a portion 177 of shaft 176 extends through a wall of housing 114, see FIG. 9. This portion may be covered by a hollow protective plug 179, see FIG. 6, so that by removing the plug the portion 177 may be manually controlled to rotate shaft 176 and hold lever 100 locked and the discharge valve 104 closed.

In addition, means are provided for advancing the closing of the discharge valve on the pump down stroke and for retarding the opening of lthe discharge valve on the pump up stroke in order to provide for a greater or less compaction of the hydraulic column to meet the particular circumstances at the well. As seen in FIGS. 4 and 5, this means comprises a ratchet clutch 184 which is positioned between lever l100 and the discharge valve control shaft 102. The ratchet clutch may be conventional 1u design, and it is apparent that by loosening nut 186, the clutch sections may be separated and the rotative angle between lever 100 and shaft 102 may be changed to advance or retard the closing of the discharge valve 104, as described above.

To prevent the timing disk 116 from rotation backward with spider 124 during each Voscillation of shaft 60, the spring-operated bolt lock -134 has been provided. The snap-action mechanism described above raises the possibility that the action of pawl may cause the timing disk to rotatively coast through an angular Vdistance 116 which is more than one tooth for each oscillation of the spider. This would upset the operation of the control mechanism for'the discharge valve, so means must be provided for positively stopping the timing disk after it advances a rotative distance equivalent to the angle subtended by one tooth, during each oscillation of spider 124.

As seen in FIG. 8, surface V138 of the timing disk has Vbeen machined to provide axially projecting wedge anchor members 190.V In addition, Va lever pawl 192, see FIGS.

13 12 and 13, is pivotally mounted in bearings 194 which are rigidly secured to the adjacent side of the housing 44. Lever pawl 192 is provided with an abutment surface '196 for engaging the edge '191 of the anchor members 190. In addition, the pawl 192 is provided with substantially parallel cam-ming surfaces 198 and 20G. As seen in FIG. 8, arm 128 of spider 124 has a knife edge 202 integrally secured on one side thereof. This knife edge 202 is positioned so on the back rotation of spider 124 (clockwise as seen in FIG. 8 and to the left as seen in FIG. l2), it will engage lever pawl 192 on its cam surface 198 and cause it to pivot so abutment surface 196 moves out of engagement with the edge 191 of the anchor members 190, see FIG. 13, freeingthe timing disk for further forward rotation (clockwise, as seen in FIG. ll).

In addition to the knife edge, a camming arm 204 is integrally secured to arm 12S of spider 124, see FG. 8. This camming arm is disposed on the side of arm 128 which is opposite to the knife edge 202, see FIG. 8, and it is positioned so that when the spider 124 reverses its direction of rotation and starts to rotate the timing disk (in the clockwise direction as seen in FlG. ll), then camming arm 204 moving to the right as seen in FIG. 13, engages cam surface 200 on the lever pawl 192. This engagement pivots lever pawl 192 toward surface 138 of the timing disk, and causes abutment surface 196 to move in the path of the edge 191 of the anchor members 190, moving with the timing disk, so that as soon as the timing disk rotates through the required angle, equivalent to the separation of the teeth on its periphery, the edge 196 of pawl 192 will abut against the edge 191 of the anchor member y19t), stopping any further rotation of the timing disk which may be due to the snap-action mechanism.

The invention may be embodied in other forms without departing from the spirit or essential characteristics thereof as set forth in the claims, and the present embodiment is therefore to be considered as illustrative and not restrictive, and it is intended to include all changes which corne within the scope and range of the claims.

I claim:

l. A device for pumping volatile liquids comprising in combination a tube, one end of said tube inserted in a pool of liquid, a plunger having a fluid passage extending therethrough Irnovably mounted in -said tube adjacent said pool of liquid, a power operated means, an operative connection between said power operated means and said plunger to cause the plunger to oscil-late in said tube, a valve mounted in said plunger for opening and closing the fluid passage therein, said valve connected to said plunger so it opens when the plunger moves in one direction in the tube and closes when the plunger moves in the opposite direction whereby the liquid in said pool is gradually pumped through said plunger and through said tube, and a quick acting discharge valve connected to said tube at a point remote from said plunger and said pool of liquid, control means connected to said discharge valve and operatively connected to said means for causing said plunger to oscillate and constructed and arranged to operate in timed relation to said means for causing said plunger to oscillate for closing -the discharge valve and interrupting the out-ward flow of liquid for any predetermined number of strokes of the plunger whereby a hydraulic column is formed in said tube which bears against the said valve in said plunger and positively forces it closed when the plunger moves in said opposite direc- Lion through the tube, said control means being constructed and arranged to then open said discharge valve after said predetermined number of strokes to dissipate said hydraulic column and permit the liquid in said tube to resume its outward flow.

2. A device for pumping Volatile liquids Ifrom a well comprising in combination a tube, the bottom of said tube inserted in a pool of the liquid, a plunger having a duid passage extending therethrough movably mounted in the lbottom of said tube, an oscillating driving mechanism, sucker rods connected between said oscillating driving mechanism and said plunger to cause the plunger to move up and down in said tube, an upward opening valve mounted in said plunger for opening and closing the uid passage therein, said valve connected to said plunger so it opens when the plunger moves downward in the tube `and closes when the plunger moves upward whereby the liquid in said pool is gradually pumped through said plunger and out the upper end of said tube, and a quick acting discharge valve connected to the top of the tube, means operatively connected to `and responsive to the oscillating driving mechanism for closing said discharge valve in timed relation to the upward strokes of the plunger and :interrupting the outward flow of liquid for any predetermined number of strokes of the plunger whereby the column of liquid in said tube forms a hydraulic column which bears against the said valve in said plunger and positively forces it closed when the plunger moves upwardly in the tube, said means being constructed and arranged to then open said discharge valve after a predetermined time to dissipate said hydraulic column `and permit the liquid in said tube to resume its outward ow.

3. The lapparat-us set forth in claim 2 wherein said means includes a shaft rotatively mounted in a support on said shaft adapted to operate said discharge valve, lever members secured to said shaft in angularly spaced relation to each other around the axis of said shaft, driving means connected to said sucker rods and movable therewith, the ends o-f said lever members movable into the path of said driving means so that as the driving means moves upward with said sucker rods it engages one of said lever members and rotates said shaft until the end of said one lever member moves out of engagement with said driving means, said lever members being positioned so the said rotation of said shaft causes the end of another lever member to move into the path of said driving means so that when the driving means reverses its direction it will engage the end of said other lever member to produce a reverse rotation of said shaft until the end of said other lever member moves out of the path of said driving means and the end of said one lever member moves back into the path of said driving means whereby the shaft and the discharge valve operate in timed relation to the strokes of the plunger, said lever members having an automatic aligning mechanism so that if the driving means engages the end of a wrong lever member as it moves in one direction the automatic aligning means will act so that on the reverse movement of said driving means t-he end of the same lever member will be in the path of the driving means and the lever members will then be in their proper position with respect to the movement of the driving means.

4. A reciprocating oil Well pump having an operating mechanism, a spring loaded normally open discharge valve connected to the outlet of an oil well processed by said oil well pump and a control mechanism for said spring loaded, normally open discharge valve, comprising a support,v a shaft rotatively mounted in said support, means connected to said shaftfor engagement with the pump operating mechanism of said oil Well pump to cause said shaft to rotatively oscillate on its aXis in synchronization with the strokes of the oil-well pump, a linkage system adapted to be removably connected between said shaft and said discharge valve for closing said discharge valve once during each oscillation of the shaft, means adapted to intermittently operate in timed relation to the operating mechanism of said oil-well pump for disconnecting said linkage system from said discharge valve for a predetermined number of pump strokes whereby said spring-loaded discharge valve will remain open for said number of pump strokes and for intermittently connecting said linkage system to said discharge valve whereby said discharge valve may be closed for a predetermined number of pump strokes, and means for holding said discharge valve closed for a minimum predetermined p0rtion of a pump stroke once it is closed.

5. The apparatus set forth in claim 4 wherein said means Afor holding said discharge valve closed for a minimum predetermined portion of a pump stroke includes a manually operated linkage override mechanism Whereby the discharge valve may beheld closed independently of the operation of the intermittently operating means and said linkage system.

6. The apparatus set forth in claim 5 including means A for adjusting said discharge valve relative to said linkage system to advance the closing of said discharge valve on'one stroke of the pump `and retard the closing on the opposite stroke of the pump.

References Cited in the tile of this patent UNITED STATES PATENTS Briggs Aug. 9, 1892 Nagel Jan. 31, 1928 Boone Aug. 29, 1939 Todd Dec. 26, 1939 Topanelian May 28, 1940 Miller et al Nov, 23, 1943 Elwert Mar. 6, 1945 Y Burrus et al Oct. 19, 1948 Dietrich Dee. 12, 1950. VHorstmann July 12, 1955

Patent Citations
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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4767290 *Apr 12, 1985Aug 30, 1988Jones Ellis OFluid pump
US6460622Apr 6, 2001Oct 8, 2002Global Energy Research, LlcApparatus and system control for the removal of fluids and gas from a well
US6615925Oct 4, 2002Sep 9, 2003Global Energy Research LlcPump control method and apparatus
Classifications
U.S. Classification417/441, 417/554, 74/593, 74/519, 74/97.1, 74/568.00R, 166/68
International ClassificationF04B47/00
Cooperative ClassificationF04B47/00
European ClassificationF04B47/00