US1758609A - Pump-operating mechanism - Google Patents

Description

Ma'y 13, 1930. G. KAMMERER PUMP OPERATING MECHANISM Filed May 24. 1927 rvlinlinnn xuununullunl Patented May 13, 1930 UNITED STATES GEORGE KAMMERER, OF

WHITTIER, CALIFORNIA PUMP-OPERATING' MECHANISM Application led May 24,

'This invention relates to pump-operating mechanism of the type suitable, for example, I for operating reciprocating deep well pumps for the pumping of oil and other liquids, such pumps involving the use of a string of sucker v rds and a polish rod at the upper end there- In the pumping of oil wells it is essential that the load on the polish lrod be counterbalanced, not only from the stand-point of increased powereiiiciency, but also from the standpoint of smooth, unlform ,operation so that the relative times consumed-'in the up and down strokes are approximately equal.

The irst counter-balancing in pumping deep well mechanism was effected by attaching a weight to that end of the walking beam to which the power is applied. This weight was either placed directly on the walking beam, so as to swing in an arc, or was connected with the walking beam by a rod and reciprocated in guides. In either of these two methods of attaching the weightthe mass was a reciprocating one and the inertia of the moving weight had to be overcome at each end of the stroke in changing the direction of motion. Such counter-balancing is far from ideal, particularly when a heavy load is to be counter-balanced at a relatively high rate of speed, because the inertia of the moving mass is not readily subject to a sudden change of direction at the ends of the stroke. With either of these ways of attaching the weight,

` if there result broken Walln'ng beams, the parting of sucker rods and,furthermore, where the equipment which attaches the weights to the walking beam is under suchy extreme strains, breakage of such equipment is quite frequent. i

To' overcome the objections resulting from connecting the weight tothe walking beam, some operators attach the weight to the band wheel. This was an improvement in one respect because of the fact that, since the weight moved continuously in a circle, it was not necessary to overcome the inertia of the move ing mass at the end of each stroke of the pump. However, when the weight is placed on the band wheel, from fifteen minutes to an hour is required to remove the weight so that 1927. seal No. 193,817.

` them when the weight is placed on the band wheel, would necessarily be extremely costly if designed to withstand such load conditions.

To avoid the objections mentioned above and arising from connecting the 'Weight to the walking beam or attaching it to the band wheel, I have conceived of placing the weight on the pitman. In s o placing the weight, it

is nearrthe point of application of the energy of the moving mass represented by the weight,

so as not to put an excessive strain on those parts that are strained when the weight is placed on the band wheel and, furthermore,

the weight has a rotary motion and thus secures `the advantage that results from placing of the weighton the band wheel.

By attaching the weight to the pitman I secure all of the advantages resulting from attaching theweight to the walking beamand all of the advantages accruing from attaching the weight to the band wheel, and I obtain none of the disadvantages of attaching `the weight to either the walking beam or the band wheel.

Furthermore, by attaching the weight to the pitman I obtain a still further advantage over attaching it to the band wheel since, on

the pitman, the weight moves in an elliptical path instead of a true circular path, as results when it is placed on the band wheel. The short axis of the elliptical path is horizontal and the long axis is vertical, thus entailing that the center of gravity of the Weight is drawn towards the center of the elliptical path in the irst half of the up and down strokes of the weight and said center of gravity moves outward from the center of the elliptical path in the second half ofthe up and down strokes of the weight. Accordingly, when the pump rods are making the first half .of their down stroke the motor that operates passes over the upper dead center and the rods reverse their direction at the bottom of the stroke, the inertia of the moving Weight has greater value than if said Weight were simply moving in a circular path. Thus, at the time of reversal of the pump rods at the lower end of the stroke, we not only have the inertia of the moving weight that we would have if it moved in the regular circle, but

there is also the inertia due to the centrifugal force upon the weight, since the weight has been moving outwardly from the center of its elliptical path. Accordingly, the weight assists the motor in reversing the sucker rods at the lower end oi their stroke and in starting the load represented by the Weight of the rods and the liquid column being pumped.

Other objects and advantages will appear yin the subjoined detailed description.

Figure 1 is a side elevation of a weighted pitman constructed in accordance with the provisions of this invention, the same being shown operablyv connected with a crank and an operating member. A fragment of a derrick is also shown.

Figure 2 is an enlarged view, partly in section, from the line indicated by 2-2, Figure 1.

Figure 3 is a view, partly in section, on the line indicated by 8 3, Figure 2.-

Referring to the drawings, the weighted vpitman is indicated in general by the character 6, and it is interposed between an operating member 7 and a crank 8. The operating member 7, in this instance, is in the form of a walking beam pivotally mounted at 9 upon a samson post` 10. To theoperating member 7 is connected a polish rod 31. In Figure 1 a fragment of a derrickis indicated 1n general by the character 11 and the samson post is tied to the derrick by a brace 12 in the customary manner. The crank 8 is liXed to a shaft'13 operated by a band wheel 14 in the manner customary in the art relating to the pumping of oil wells. In fact, the entire construction, depicted in Figure 1,j is typical of the constructions used in the art or arts relating to oil production, excepting for the novel features hereinafter described.

The weighted pitman 6 comprises a pitman bar 16 connected by a strap 17 to the outer end of the operating member 7, said strap passinor over the top of the operating mem-- ber. f course, the-pitman bar 16 can be connected with the operating member 7 by any other suitable means than the strap 17.

The crank 8 carries a crank pin 18 which may be adjusted to diterent positions along the crank and, for this purpose, the crank is provided with a number ot holes 19 in which the crank pin may be selec-tively positioned in a manner well understood in this art. The pitman bar 16 turns on the crank pin 18 in the usual manner.

Secured to the pitman bar 16 is a weight support which in this instance, is in the form of a basket or iframe comprising a number of arms 20 secured by bolts 21, or equivalent fastening means, to the pitman'bar 16. In this instance, the arms 20 constitute straps 'eX- tending around three sides of the pitman bar and the arms project beyond one edge of the pitman -bar asuliicient distance to receive between them a number of counter-balancing weights indicated at 22.

In this vparticular instance, the arms 20 are connected together by upright members 23 positioned inside of the arms. The uprights 23 may be secured by rivets 24 or otherwise to the arms 20. In this instance, there extends from the lower end of the outermost upright 23 a diagonally extending brace 25 y which is connected with the lower end of the pit-man bar 16. The members 23, in this instance, are channel-shaped and arranged in pairs, each otl the weights being adapted to be received between the flanges 26 of the members 23 of each pair. In this instance, the members 23 of each pair,'are separated farther at their upper ends than at their lower ends so as to form a downwardly and inwardly tapered receptacle for the weight 22. lhe weights 22 may be of the same or different sizes, as desired and, 1n the present instance, they are shown of the same size and are, therefore, interchangeably mounted in the basket that supports them. The weights are Wedge-shaped to tit the receptacles and the advantage of this is that the Weights are thereby tightly held and can not rattle or move about orbe thrown out of the basket.

It is to be understood that one or more of the weights may be employed at one time for counterbalancing the load on the operating member, according to the amount of said load. It will be seen that besides the possibility. ot adjusting the counter-balancing weight by utilizing one or more of the weights 22, a

rfurther adjustment is possible, when one or two weights are entirely removed from the lbasket, by changing the remaining weight or weights to a diiierent receptacle or receptacles as the case may be. The receptacles for the weights are arranged in line so that they are ldifferent distances from the crank pin 18 and the weight carrying basket may be considered as one arm of a weighted lever ot which the crank 8 constitutes the other arm. Itwill now be readily seen that the farther lll) llt

vthe Weight or Weights be positioned from the crank pin 18 the greater will be the leverage at any given angle between the pitman and its stroke that corresponds to the upstroke of the ump, not shown, connected with the inner nd of the operating member 7. Accordly occupied by the removedl Weight.

A ble counter-balancing the load of the pump ingly, assuming that the Weight farthest from the crank pin 8 has been entirely removed, the remaining counter-balancing Weight may be further adjusted by placing either of the remaining Weights 22 in the receptacle former- Thus, With any one of the Weights removed three different counter-balancing loads may be imposed on the pitman bar 16 and', if there are three Weights as illustrated, it Will be possible to secure seven different counter-balancing Weight effects by simply omitting one of the Weights and. changing the position of the remaining Weight or Weights.

In order to expeditiously eect removal, replacement and shifting of the Weights into different receptacles when it is desired to make a change in the counter-balancing effect, I provide a hoisting tackle suspended .'from the operating member 7 in position to be readily engaged With any one of the Weights 22. The hoisting tackle comprises a cable 26 rove over a pulley27l which is ro-` tatably connected with the operating member 7 lOn one end of the cable 26 is a hook 28 adapted to be selectively engaged With eyes 29 which are fixed in the upper ends of the Weights 22. The hook 28 and eyes 29` constitute one form of cooperating means on the cable and Weights for detachably connecting said cable With said Weights. The other end of thecable 26 engages .a hand operated Windlass 30 which is mounted, in thisl instance, on thesamsonpost 10. Although it is not new-to employ a tackle for handling objects, it will be noted that the arrangement of the tackle described above facilitates handling the Weights because it is mounted in the manner described.

The construction and operation of the invention Will be clearly understood from the foregoing description and brieflyk stated, the operation is as follows: The requisite number of Weights 22'Will be positioned y1n the appropriate receptacles lfor as near as possiparts and liquid column bein raised, as' described above more in detai. On the upstroke of the linner end: of they operatmg member 7, the Weights will descend and aid the motor that operatesthe shaft 13, in raising the load represented by the pump parts and liquid in the Well. The Weight of the pump parts and liquid will then aid in raising the Weights as the pump operates on its downstroke.

It is to be noted that, when the Weight is I thus centrifugal force aids the motor in raising the Weight during the latter half of the upper stroke of said Weight. The energy in themoving mass is thus increased so vas to become effective at the time of reversal of stroke so as to overcome the inertia of the stationary rods and of the liquid column being pumped. This produces a smoother operation of the pump and, accordingly, there is less strain on the various parts asherein-l before explained in detail.

I claim: l. In a pump-operating mechanism, a

,Weighted pitman comprising. a pitman bar,

a frame projectin laterally from the pitman bar, and Weig ts removably set Within said frame.

2. In a pump-operating mechanism, a Weighted pitman comprising a pitman bar, a frame projecting laterally from the pitman bar and provided with a number of receptacles, and Weights removably positioned in the receptacles.

3. In a pump-operating mechanism, a Weighted pitman comprising a pitman` bar, a frame projecting laterally from the pitman bar and provided With a number of 4downwardly and inwardly tapered receptacles, and Wedge-shaped Weights removably fitting in said receptacles 4. In a pump-operating mechanism, a Weighted pitman comprising a pitman bar, a frame projectinglaterally fromthe pitman bar and provided W-ith a number of receptacles, and Weights interchangeably fit- 4ting in the receptacles.

5.. The combination with Aan operating member and a crankprovided With a crank pin, of ay pitman bar engaging the crank pin and connectedk with the operating member, a number of receptacles connected with the p'it- 1 75 the pump rods at the lower end of the pump man bar and positioned different distances from the crankpin, and Weights removably fitting in the receptacles.

6. The combination with an operating member and a crank provided With a crank pin, of a pitman bar engaging the crank pin and connected with the operating member, a number of receptacles connected With the pitman bar and positioned different distances from the crank pin, and weights interchangeably fitting in the receptacles.

7. A pump-operating mechanism comprising a pivoted operating member adapted for connection at one end with the polish rod of a pump, av pitman connected with the other end'of the operatingnmember, a rotatably mounted shaft provided with a crank connected with the pitman, and a counter-balancing Weight mounted on the pitman in a position to increase the effective level` arm of the Weight when the polish rod is Working on the pump discharge stroke.

8. In a pitman for connection With the Walking beam and band Wheel of a pumping rig, a body member having a Walking beam stirrup at one end and a band Wheel crank journal at the other end, a Weight-supporting element attached to the body member, and Weights' removably attached to said element. l L

9. In a pitman for connection with the Walking beam and band Wheel of a pumping rig, a body member having a Walking `beam stirrup and a band Wheel crank journal, a Weight-supporting element on the body member adjacent the journal, and Weights removably attached to said element.

Signed at Los Angeles, California this 16 day of May, 1927.

GEORGE KAMMERER.

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