US2228095A - Adjustable counterbalance - Google Patents

Description

1941- R. E. SCHULLER ,095

ADJUSTABLE COUNTERBALANCE Filed Nov. 12, 1938 2 Sheets-Sheet 1 Y QRESCHULLER Jan. 7, 1941. R E SCHULLER v 2,228,095

' ADJUSTABLE COUNTERBALANCE Filed Nov. 12, 1958 Z SheetS-Sheet 2 j RESCHULLER. 5 mgg elik Patented Jan. 7, 1941 UNITE STATES ATENT OFFICE Lufkin Foundry & County, Tex.

Machine Company, Lufkin Application November 12, 1938, Serial No. 239,955

3 Claims.

The invention relates to an improvement in adjustable ccunterbalances of the type which are applied to well pumping units.

In the pumping of a well various problems in counterbalahci-ng are encountered due to the variation in the depth of a well, the specific gravity of the fluid being pumped, the crookedness of the hole, and the weight of the equipment which must be operated. When all of these it circumstances-are taken into consideration it is desirable to have a counterbalance weight which is readily adjustable to a very accurate degree so that there will be the least power consumption.

With the foregoing in mind, it is one of the objects of the invention to provide a universally adjustable counterbalance weight device for pumping units.

Anotherobject of the invention is to provide a counterbalance device which can/be adjusted with minute accuracy in order to exactly counterbalance the weight in the well.

Another object of the invention is 'to provide a circularhub member upon which a pair of 4) weight members are .circumferentially adjustable to any position independently of each other.

Another object of the invention is toprovide a counterbalancing device in which a pair of counterbalance weights may be adjusted to lead,

coincide or lag with respect to each other or with respect to the wrist pin openings.

Another object of the invention is to provide a counterbalance weight support member having a pair of parallel trackways thereon for the ad- ,35 justment of counterbalance weights.

It is also an object to provide a cranking unit with an adjustable counterbalance on the back .side crank so that one or more wellsmay be counterbalanced.

Another object of the invention is to provide a support member which may be affixed to a crank shaft and haveadjustable counterbalance weight members affixed thereto.

Other and further objects of the invention will be readily apparent when the following description is considered in connection with the accompanying drawings wherein:

Fig. 1 shows a side elevation of the counterbalance support and the counterbalance weights afiixed thereto.

Fig. 2 is a section taken on the line 2-2 of Fig. 1.

Fig. 3 is a diagrammatic view showing the general assembly of the device in operation.

Fig. 4 shows a view which is partly a top plan View and partly section on the line 4-4 of Fig. 6, and shows a modification of the invention where the present crank has been applied to a cranking unit as a back side crank so that a plurality of wells may be pumped by the back side crank while at least-one well is being cranked by the front crank.

Fig. 5 is an elevation on the line 5-5 of Fig. 4 looking toward the front crank.

Fig. 6 is a side elevation looking at Fig. 4 from the opposite side and illustrating the back side crank.

In Fig. 3 the walking beam 2 rocks on the center iron 3, which is supported on the Sampson post 4. The pitman rod 5 is connected to the wrist pin 6 in the wrist pin opening 1 in the crank arm portion 8 of the support or crank disc 9.

The pumping unit which is in the nature of a gear reduction box ID has a shaft H projecting laterally therefrom and the support member 9 is fixed to this shaft by the keys [2 which lit in the keyways iii. A through bolt I4 passing through the lugs l5 and l 5 clamps the keys about the shaft H. In this manner the support member 9 is firmly fixed for rotation with the shaft l l.

A plurality of wrist pin openings 1 have been provided so as to vary the length of the stroke of the pump.

Fig. 2 shows a sectional view of the support member I9 and illustrates the arrangement of the rim 2t thereof, which as will be observed is of considerable width so as to provide a pair of spaced trackways 2! and 22. These trackways are identical and are slightly indented to provide the opposite shoulders 23 and 24. These shoulders extend entirely around the periphery of the support member.

Eachof the trackways 2i and 22 are arranged to adjustably support a counterweight such as the weight 3.6. This weight is of particular construction, in that it has the body portion 3|, which has a shank 32 connected therewith. This shank is provided with a substantially semi-circular base 33 which is of a configuration to fit the trackway 22. The ears 34 at each side of the shank 32 are arranged to receive the bolts 35 and the nuts 35 thereon. In order that the weight 30 may be clamped on the trackway 22 a strap or band portion 31 is placed on the opposite half of the trackway 22. This band 31 is substantially semi-circular and has the ear-like portions 38 thereon, which have openings therethrough to receiVe the bolt 35. The head 39 of the bolt 35 bears against this ear 38 so that when the nut 36 is drawn up the strap 31 and the Weight 30 will be clamped rigidly to the support member 9. This construction is duplicated on the opposite side of the support member and by proper adjustment of the nuts 36 the weight can be adjusted to any desired position. It will be observed that the indicia 49 adjacent the periphery of the support member 9 indicates any relative angular position so that instructions may be given to the operator to set the weight at any desired angular position.

In order to adjust the weight it is only necessary to loosen the nuts 36 somewhat and to either slide the weight and the strap 31 circumferentially around the support member or to turn the crank shaft, so that the Weight member 3| is in its lowermost position, loosen the nuts 36 and then turn the crank shaft slightly until the weight arrives at the desired position, whereupon the nuts can then be tightened.

The weight member 42 and the strap 43 are identical with the weight 3| and strap 31 except that they are positioned on the trackway 2|.

Particular attention is directed to the fact that the weights 3| and 42 are not in the same vertical plane, that while they are parallel and are both circumferentially adjustable they can be adjusted to either coincide, lead, or lag with respect to each other or with respect to the crank pin openings 1. If it is desired to obtain a large amount of counterbalance at any one particular point the two weights may be adjusted to coincide with each other, which is believed to be a feature of particular advantage which has not been heretofore possible with counterbalance devices where a plurality of weights were circumferentially adjustable upon the same trackway.

A plurality of key-ways l3 have been provided so that the support member 9 may be taken ofi' periodically and turned a portion of a revolution so as to vary the load upon the gears and to obtain a more uniform wearing of the parts.

Figs. 4 to 6 inclusive show the constructionwhich has just been described as applied to a double cranking unit where as seen in Fig. 4 the pumping unit is illustrated generally at I and. has the crank shaft H projecting from both sides of the gear box.

Fig. shows a construction quite similar to that described in connection with Fig. 3 except that a somewhat different type of counterbalance arm 50 has been afiixed to the shaft II. This particular type of arm has the adjustableweights 5i which are slidable along the sides of the crank 58 and to which crank the wrist pin 6 is connected. The walking beam is the same as: shown in Fig. 3 and has beam rods 52 passing down into the well 53.

The opposite end of the crank shaft I I has a. counter-balance Weight unit such as shown in. Figs. 1 and 2 connected therewith. A wrist pin. 55 is connected into one of the openings I and as seen in Fig. 6 has a connecting rod 60 arranged thereon. This connecting rod extends to a swing H which is mounted on a support 62 and is pivoted on the center iron 63. This swing includues a beam 65 which has the converging braces 66 meeting at an apex 61 to which the pull rods 68 and 69 from two spaced wells may be connected.

The particular construction of this swing is disclosed in the application for patent of J. L. Fincher filed August 17, 1936, Serial No. 96,148 for Combination swing and knockout for cranking units, while the standard crank 50 of Fig. 5 is disclosed in the patent to Trout, No. 1,588,784, granted June 15, 1926.

The construction of this modification is of particular advantage because at least three wells may be pumped with a single pumping unit and the universal adjustment of the weights 3| and 42 permit any desired amount of counterbalancing of the swing 6| regardless of whether one or more wells are connected therewith.

Broadly the invention contemplates an adjustable counterbalance weight device wherein the weights may be universally adjustable with respect to each other and with respect to the wrist pin connection, and adjustment for a plurality of wells may be made on the counterbalance.

What is claimed is:

1. An adjustable counterbalance device for well pumping units having a pitman rod comprising a body member, means to afilx said body to the shaft of the pumping unit, means to connect the pitman rod to said body, a pair of spaced grooves about the periphery of said body, a counterbalance weight member clamped in each groove for adjustment about the body, said weights being independent so that they may be adjusted to :any circumferential position, and means to independently clamp each weight to the body member.

2. A counterbalance device of the character described comprising a concentric support member to be afiixed to a pumping unit shaft, an an- .nular groove in its periphery, a Weight, a shank on said weight to fit in said groove, a cap member to also fit in said groove, and means to clamp said cap and shank together to enclose said support member and afiix the weight for rotation with the member.

3. A counterbalance device of the character described comprising a concentric support member to be afiixed to a pumping unit shaft, an an- :nular groove in its periphery, a Weight, a shank on said weight to fit in said groove, a cap member to also fit in said groove, and means to clamp .said cap and shank together to enclose said sup- ;port member and affix the weight for rotation with the member, and a second groove and second weight and cap also on said support member, :said Weights being independent so that the two weights may be adjusted to lead, lag or coincide.

ROBERT E. SCHULLER.

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