US2169493A - Pumping device - Google Patents

Description

5, 1939 G. T. HUMPHREY 2,169,493

PUMPING DEVICE Filed Oct. 23, 1936 2 Sheets-Sheet l 1939 ca. T. HUMPHREY 2,169,493

PUMPING DEVICE Filed Oct. 23,' 1936 2' Sheets-Sheet 2 gwuc-wtou Patented Aug. 15, 1939 UNITED STATES PUMPING DEVICE George T. Humphrey, Dallas, Tex, assignor to Republic Supply Company, Houston, Tex.

Application October 23, 1936, Serial No. 107,119

3 Claims.

This invention relates to new and useful improvements in pumping devices.

One object of the invention is to provide an improved pumping device wherein relatively less power is required for performing the pumping operation and the efficiency of the device is increased.

An important object of the invention is to provide an improved pumping device including a swinging beam which is so constructed that the leverage is increased on the lifting or upstroke and decreased on the lowering or downstroke, whereby the power necessary to perform the pumping operation is reduced.

A further object of the invention is to provide an improved pumping device including aswinging beam arranged to be operated by a power unit wherein, at the beginning of the lifting or upstroke of the beam, substantially all of the power output of the power unit is utilized to impart a starting motion to the beam, whereby the natural inertia and weight of the fluid column being pumped is overcome, and the upstroke is started smoothly and without jar.

Another object of the invention is to provide an improved pumping device including a swinging beam which is so constructed that the lifting or power stroke is performed during a greater part ofthe pumping cycle than the lowering or return stroke, whereby a slow lifting stroke and a quick return stroke are obtained.

Still another object of the invention is to provide an improved pumping device including a walking beam, with means for uniformly accelerating the speed of travel of said beam from zero at the start of each stroke to a maximum at mid-stroke, and then uniformly decelerating the speed of travel from the maximum at mid-stroke to zero at the end of the stroke, this action occurring on both the'up and downstroke of the beam, whereby vibration and jarring of the device are substantially eliminated, which makes for smooth operation.

A still further object of the invention is to provide an improved pumping device including a swinging beam which is so constructed that it may be readily connected to or disconnected from a power unit, and which is directly connected to the crank arm, whereby the usual pitman and the bearings incidental thereto are eliminated.

A construction desi ned to carry out theinvention will be hereinafter described, together with other features of the invention.

The invention will be more readily understood from a reading of the following specification-and by reference to the accompanying drawings, in which an example of the invention is shown, and wherein:

Figure 1 is a side elevation of a pumping device constructed in accordance with the invention, showing the position of the device at the start of the lifting stroke,

Figure 2 is a view similar to Figure 1 showing the device at the finish of the lifting stroke,

Figure 3 is a transverse, sectional view taken on the line 3-3 of Figure 1,

Figure 4 is a side elevation of a modified form of the invention,

Figure 5 is an enlarged view of a portion of the beam shown in Figure 4, and

Figure 6 is an enlarged, transverse, vertical, sectional View taken on the line 6-6 of Figure 5..

In the drawings, the numeral l8 designates a suitable base upon which a vertical Samson post or other support H is mounted. The Samson post is braced by suitable inclined members I2, which may be welded, bolted or otherwise secured thereto to form a rigid structure.

On the upper end of the Samson post I l a suitable saddle !3 is mounted, and an elongate swinging beam I 4 is pivoted on a transverse pivot pin I5 which extends across the saddle, whereby the beam may swing freely in a vertical plane. An ordinary arcuate horsehead IE5 is secured to one end I! of the beam, which for the sake of clarity shall be hereinafter called the outer-end. Well pump rods 18 are connected to the upper end of the horsehead by means of a flexible cable It. 'It is noted that the arcuate face of the horsehead is so formed that the point of vertical lift of the' pump rods is equidistant from the pivot !5 for all positions of the beam. Manifestly, when the beam is swung on its pivot, a reciprocating vertical motion. will be imparted to the pump 'rods, whereby the pump in,the well' (not shown) is operated. Y

For imparting a swinging movement to the beam, the opposite end 28, hereinafter called the inner end of the beam, is connected to 'a power unit 2|, which unit is supported on a block Ill.

The power unit has the usual drive shaft 2| securely connected to the inner end 20 of said beam by plates or straps 24, which are riveted, welded or otherwise secured thereto in such a manner that the top of the extension 23 lies in alinement with the bottom of the beam M. A suitable rail or roller track 25 is securely mounted on. top of the offset extension of the beam, and a flanged drive roller 26 is carried by the outer end of the crank arm 22 and is adapted to ride on the rail and travel longitudinally of the beam I4 thereon in the same longitudinal plane with relation to the beam, which plane intersects the pivot I5. The roller is mounted on a pin o-r'bolt 21 which extends through an opening 22 in the cranklarm 22 and is secured thereto by a nut 28 or in any other suitable manner. It is noted that a plurality of openings 22' are provided in the crank arm, whereby the position ,of the roller on the arm with relation to the drive shaft may be varied. It is also noted thatthe crank arm: is made ,arcuate, whereby, when the beam is at the top or bottom of the stroke, the roller will engage the rail at the same point regardless of the position of the roller on the arm.

An angular bracing member 29 has its shorter leg pivoted on a pin 30 to the outer end of the extension 23 of the beam, while its longer leg overlies therail 25 and the extension 23, and is fastened to the inner end 20 of the beam by bolts 3|, or other suitable means. Thisbracing member serves to strengthen and reinforce the extension, 23 to make the same rigid. It will be seen that by" removing the bolts 3| the bracing member may be swung on the pivot pin 30, giving free access to the roller 26 and the rail 25.

It is noted that the length of the beam is made such thatthe distance between the arcuate face of the horsehead I6 and the pivot I5, which forms a lever arm A, and the distance between the pivot I5 and the point of'contact of the roller on the rail 25, which forms a lever arm B, areequal 'when the crank arm is in a position at right angles to the rail, or at the top and bottom of the pumping stroke. a This is an important feature of the'invention. t r

In operation, with arrangement described, it

will be seen thatwith the beam in position-at the start of the upstroke, as shown in, Figure '1, the crank arm is at right angles to the upper edge of the rail and the lever arms A and B are equal. However, upon'rotation of the crank, arm in a counter-clockwise direction, it is obvious that the roller 26 will travel'on the rail 25 and that the distance between said-roller and the pivot I5 is increased, thereby increasing the lever arm B.

This i'ncreaseln the leverarm B, while the lever arm A remains constant, gives the power unit additional leverage during the lifting stroke, thereby requiring less power output than if the lever arms remained equal and constant in length throughout the rotation of the crank arm. 7 This increase in the leverarm B reaches a maximum when the drive roller 26', the drive shaft 2'I and the pivot l5 are in horizontal alinenient. From this point of maximum length of the leverarm B, -further rotation of the -crank arm decreases downstroke.

arm B, from the point of equal length with the lever arm A, to a minimum when, the roller drive shaft and pivot I5 are again in horizontal alinement. From this minimum point, the lever arm B increases, as rotation of the crank arm continues, until the beam is again at the position shown in Figure 1, which is the finish of the Here, the lever arms are again equal and the lifting or upstroke is started. It

will be seen that this shortening of thelever arm in a direction parallel to the upper edge of the rail 25. During said first few degrees of rotation of the crank arm substantially all of the power output of the power unit is utilized to'impart a starting motion to the beam to overcome the weight and natural inertia of the fluid column being pumped, whereby the upstroke is started smoothly and slowly without jar,.the re-' by reducing the strain on the device.

The velocity of movement of the crank arm is gradually increased as the crank arm is further rotated, said movement of the beam being substantially a simple harmonic motion, until a maximum is reached when the crank arm roller,

the drive shaft and the pivot pin I5 are in hori,

zontal alinement. From this point the acceleration of the beam becomes negative and the velocity of movement of the beam decreases graduallyto zero at the top of the lifting stroke, Figure 2, where the crank arm is at right angles' to the beam.

From the finish of the lifting stroke, continued rotation of the crank arm starts the lowering.

stroke, during whichfthe movement of the beam is similar to that of the lifting stroke, and the beam returns to its lowered position, shown in Figure 1, which completes the-cycle.

It will be seen, by reference to the drawings,

that the arc of travel of the crank arm during the lifting stroke is greater than degrees and thereby is greater than the arc of travel during the lowering stroke. slow, smooth, powerful upstroke is obtained,and

' the additional leverage needed on the upstroke is gained'by the increase in the lever arm B, whereby strain on the device is substantially reduced. The smaller are through which the crank arm travels on the downstroke and the relative shortening of the lever arm B permits arapid downstroke, whereby less power output of the power unit is required. It is'also noted that, due to the sub- With this arrangement a stantially simple harmonic reciprocating motion,

of the beam during the pumping cycle, jar and the relative strain caused thereby is substantially eliminated.

For any given rateof rotation of the crank arm,

itwill be seen that, with the arrangement here-; inbefore described, an equal volume of fluid can be lifted with less poweroutput and less strain on the device than could be lifted with a'similar beam in which the lever arms remain constant,

ure 4, wherein a swinging beam 30, being the same in all other details as the device hereinbefore described, has a portion of its inner end cut out to form an elongate opening 3|. A bracing member 32 is secured by rivets, or other suitable means, to the underside of the beam 30 and connects the lower edges of the cutaway opening 3|. The opening is adapted to receive a rail 33 similar to the rail 25 previously described, which rail is securely mounted on the upper side of the bracing member 32 within the opening. The roller 26 of the crank arm travels on this rail in the same manner as in the previous form, and rotation of the crank arm swings the beam in a vertical plane.

The same advantages are evident in this form of the beam as in that previously described and in addition, it will be seen that this form of the invention may be readily applied to the usual walking beam to obtain the advantages of this invention.

What I claim and desire to secure by Letters Patent is:

1. A pumping device including, a support, a walking beam pivotally mounted on said support and provided at one end with a head having an arcuate working portion formed on a radius from the pivotal axis of the beam and having a flexible operating connection with a pump rod whereby the rod reciprocates vertically in a straight line when the beam is rocked said beam having an elongate longitudinal opening in its opposite end portion, a longitudinal track member mounted on the beam in the lower part of said opening, power means including a crank arm rotatable about an axis located in the same horizontal plane as the pivotal axis of the beam and at a distance therefrom substantially equal to the radius of the arcuate head portion at the opposite end of the beam, and a roller mounted adjustably on said crank arm whereby to be positioned at diiferent distances from the axis of the arm, the adjustment of the roller on said crank arm being arcuate on a radius through the axis of the arm from the pivotatl axis of the beam and said roller engaging said track member and traveling thereon with its axis coinciding constantly with a fixed line of the beam extending longitudinally through the pivotal axis of the beam.

2. In a pumping device of the character described, a walking beam having a head at one end with an arcuate pump rod operating portion formed on a radius from the pivotal axis of the beam, said beam having a longitudinal track member on its opposite end portion, power means including a crank arm rotatable about an axis in substantially the same horizontal plane as the pivotal axis of the beam and at a distance therefrom substantially the same as the radius of said arcuate head portion of the beam, said crank arm having a series of apertures arranged arcuately on a radius through the axis of the arm from the pivotal axis of the beam, and a roller having a shaft mountable selectively in one of said apertures to adjustably attach the roller on said crank arm whereby to vary the length of stroke of the walking beam, said roller in every adjustment thereof engaging the longitudinal track member at a point on a line at right angles to the track member and intersecting the axis of the crank arm when the walking beam is at the limit of its stroke, the roller traveling on said track way with its axis coinciding constantly with a fixed line of the beam extending longitudinally through the pivotal axis of the beam when the crank arm is rotated.

3. The herein described walking beam structure for pumping devices, said beam having provision at one end for reciprocating a pump rod, a supporting element fixed to the opposite end portion of the beam and extending downwardly beyond the under side thereof, a flanged extension member fixedly secured at its inner end to the downwardly extended portion of said supporting element and an angular bracing member having one arm thereof hingedly attached to the outer end portion of said flanged extension member, the other arm of said bracing memebr extending longitudinally inward above said flanged extension member and detachably bolted to the outer upper end portion of the beam body proper, and a longitudinal track member mounted on the upper side of said flanged extension member with a longitudinal elongate opening between the track member and said angular bracing member thereabove.

GEORGE T. I-IUMPHREY.

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