US2074792A

US2074792A - Shaft counterbalance

Info

Publication number: US2074792A
Application number: US704580A
Authority: US
Inventors: Joe A Lyne; Mater Robert Griffin De La; John M Cooper
Original assignee: Parkersburg Rig and Reel Co
Current assignee: Parkersburg Rig and Reel Co
Priority date: 1933-12-29
Filing date: 1933-12-29
Publication date: 1937-03-23
Anticipated expiration: 1954-03-23

Description

March 23, 1937. v V J. A. LYNE ET Al. 2,074,792 I SHAFT COUNTERBALANGE Filed Dec. 29, 1933 4 Sheets-Sheet l J. A. LYNE ET AL SHAFT COUNTERBALANCE March 23, 1937.

Filed Dec. 29, 1933 4 Sheets-Sheet 2 TEQ March 23, 1937.

J. A. LYNE ET AL SHAFT COUNTERBALANCE 4 sheets-sheet 5 Filed Dec. 29, 1933 :wua/wfm 5. M MATE 1M. Goo/ .5

March 23, 1937. I J. A. LYN: ET AL 2,074,792

SHAFT GOUNTERBALANCE Filed Dec. 29, 19:53 4 Sheets-Sheet 4 J A. LY/YE: 2 GD: 1A MA TEZ JMC'OOPEQ cmwQ:

Patented Mar. 23, 1937 UNITED STATES- PATENT OFFICE ao'imsz SHAFT COUNTERBALANCE Joe A. Lyne, Houston, Tex., Robert Griffin De La Mater, Parkersburg, W. Va., and John M. Cooper, Houston, Tex., assignors to The Parkersburg Rig & Reel Company, Parkersburg, W.- Va., a corporation oi. West Virginia Application December 29, 1933, ScrialNo. 704,580

12 Claims. (Cl. 74-591) This invention relates to shaft counterbalances, and more particularly to a counterbalance for use with oil well pumping apparatus.

Several types of counterbalanoes have been 15 apparatus is being used for drilling or during the usual cleaning operations. The present types of counterbalances usually are quite difiicult to attach and detach because of the diiliculty in handling the heavy weights and because of the 20 complicated natures of the constructions.

Moreover, the present types of counterbalances sometimes require especially constructed pumping apparatus, such as special jack post units, with more than the usual clearance between the crank 25 and jack post, and some forms of counterbalances require special pitman connections for the reason that the usual clearance between the pitman and crank is insufficient. Some types of prior constructions also are disadvantageous if not dan- 30 gerous for the reason that torque and radial loads are carried by the bolts employed for connecting the counterbalances to the cranks. Other disadvantages are present in prior constructions; but such disadvantages need not be referred to in detail. 7

a An important object of the present invention is to provide a counterbalance construction wherein novel interfitting means between the crank and the weight means relieves the attaching bolts of 40 an torque and radial loads.

A further object is to provide a counterbalance particularly adapted for oil well pumping apparatus having means whereby the counterbalance readily may be mounted and demounted with rewhich may be employed with conventional oil well pumping apparatus, thus eliminating the use of special or altered equipment.

A further object is to provide novel means for connecting additional weights to the counterbalance.

A further object is to provide a novel counterbalance structure which is adapted to be secured against one face of a special crank without requiring additional clearance between the crank and the jack post or between the crank and the driving pitman.

A further object is to provide a counterbalance which may be centered wtih respect to the crank to which it is connected or arranged in lagging or leading relation with respect" thereto.

A further object is to provide the highest possible emciency in the distribution of the weight in the counterbalance.

Other objects and advantages of the invention will become apparent during the course of the Figure 4 is a similar view on line 4-4 of Fig-f 4 ure 1,

Figure 5 is a side elevation of the jack post crank, detached, v

1 Figure 6 is a similar view of the main weight unit,

Figure '7 is a similar view of one of the auxiliary weights, V

Figure Bis an enlarged detail sectional view on line 8-8 of Figure "I,

Figure 9 is a detail perspective view of a hanger rod, 7

Figure 10 is a side elevation showing the counterbalance in use with a geared speed reducer,

Figure 11 is a fragmentary end elevation of the same, the crank and counterbalance weight being shownin section,

rod holder,

Figure 13 is a face view of the same, and, Figure 14 is a. plan view of the same. Referring to Figures 1 to 4 inclusive, the in- Figure 12 is a side elevation of a supporting vention has been illustrated as being applied to a jack post shaft l0 supported in bearings H and I2 mounted on the jack posts I3 and I4. The jack post bearing II is provided on opposite sides with ears |5 which may be an integral part of the bearing or attached to any usual bearing and having apertures |6 therethrough for a purpose to be described. Y

A crank I1 is keyed to the jack post shaft as at l3 and, extends radially therefrom a substantial distance. Centrally of its width, the crank H is provided with a relatively heavy ribbed portion l9, and the ribbed portion of the crank is provided with a series of openings 20 adapted to receive the usual pitman wrist pin which forms no part of the present invention and has not been shown in the drawings. The hub portion of the crank is provided with ears 2| and these ears and the adjacent portions of the crank lying therebelow are suitably grooved as at 22 for a purpose to be described.

The free end of the crank is enlarged-transversely of the plane of the jack post shaft. as at 23. Such portion of the crank is provided at its end portions with bolt receiving openings 24, and the outer face of the adjacent portion of the crank is recessed as at 25 to receive the bolt heads, for a purpose to be described. A central bolt hole 26 also is provided through the free end of the crank, equidistantly spaced from the bolt holes 24, and the bolt hole 26 is vertically enlarged for a purpose to be described.- The opening 26 also is surrounded by a counter-sunk recess 21. The rear face of the crankradially inwardly of the bolt holes, is provided with an outstanding transversely tapered arcuate rib 28 arranged concentric with the shaft I0 (see Figure 3). The extremity of the free end of the crank is provided with integral lugs 29, for a purpose to be described, and these lugs preferably are tapered at their sides and ends.

The main weight unit is illustrated in Figures 1 to 5 inclusive, and is indicated as a whole by the numeral 30. The weight unit is substantially arcuate from end to end and when in operative position, is concentric to the axis of the shaft Ill. The weight unit is provided with an arcuate groove 3|, preferably extending from end to end. and adapted to receive the rib.28 of the crank. As shown in Figure 3, the rib 26 and groove 3| are of corresponding cross-sectional shape. Adja- -cent the extremities of the weight member, horizontally elongated openings 32 are provided, for a purpose to be described, and these openings are inclined downwardly toward the jack post, as

.crank I1 is arcuate and seats against the inner face of the rib 33, and this rib is substantially concentric with the shaft 16. Radially inwardly of the rib 33, the weight member is provided with bolt receiving openings 34 arranged in an arcuate line corresponding to the arcuate arrangement of the

openings

25 and 26 and spaced the same distance apart as the latter openings. The openings 34, however, are preferably five in number, the two end openings 34 being seen beyond the edges of the crank H in Figure 1. The purmember and two of the recesses are adapted to receive thelugs 29 at the free end of the crank |1. It will be apparent that the lugs 29 are movable transversely into the recesses 35.

The rib 33 is provided wtih a plurality of slots I 36 and each of these slots is enlarged at its radially outer end as at 31. Within the enlarged portion 31 of each of the slots, the weight member is provided with an opening 38 extending therethrough and inclined upwardly toward the jack post as shown in dotted lines in Figure 4. At each side of the center of the length of the weight member, a pair of recesses 39 are formed in the face of the weight member radially outwardly of the rib 33. The recesses 39 are preferably tapered at their sides as indicated in Figure 6. Radially outwardly of the recesses 39, the weight member 3|! is provided with bolt openings 40 for a purpose to be described.

The weight member is adapted to support a plurality of auxiliary weights against the outer face thereof radially outwardly of the rib 33. Referring to Figures 1, 7 and 8, the numeral 4| designates one of a plurality of auxiliary weights each of which is approximately one-half the length of the weight member 30 to facilitate the lifting and applying of the auxiliary weights, and also to provide means sothat the auxiliary weights may be mounted in the center only or to one side only of the weight member instead of in complementary pairs. These auxiliary weights accordingly are secured in complementary pairs to the weight member 30. The latter member is preferably slightly flattened centrally of the length of its radially outer face as at 42, for a purpose to be described, and each weight 4| has its radially outer face flattened at its ends as at 43 to correspond to the flattened face 42 of the main weight member.

Each auxiliary weight is provided with a pair of integral lugs 44 projecting from one face thereof and corresponding in shape and arrangement to the recesses 39 to be received therein. The face of each auxiliary weight opposite the lugs 44 is provided with a pair of recesses 45 correspending in shape and arrangement to the recesses 39 and adapted to receive the lugs 44 of additional auxiliary weights, as will become apparent. Each weight member is further provided with a plurality of bolt receiving openings 46 corresponding in arrangement to the openings 40. The auxiliary weights 4| are relatively thin and several layers of the weights may be employed when desired. The outermost of the series of auxiliary weights, however, is preferably provided with recesses 41 surrounding certain of the openings 46, as shown in-Figure 3. Bolts 48 are employed for securing the auxiliary weights to the main weight member, and each of these bolts is provided with a head 49 arranged in a recess 50 provided in the inner face. of the weight member 33. The nuts 5| of the bolts'are arranged in the recesses 41.

As previously stated, the present apparatus is adapted for use with conventional jack post struc tures without increasing clearances between the crank and the jack post and without using any special pitman connecting means. In order to 5 in thickness beyond the rib 33. The outer face of the outermost auxiliary weight and the opposite inner face of the main weight member accordingly taper toward each other to insure proper clearance between the main weight and the jack post and between the auxiliary weights and the pitman.

A plurality of bolts 52 are utilized for securing the main weight member 35 to the crank, and these bolts project through the openings 34 of the main weight member and through the

bolt openings

25 and 26 of the crank. Each bolt 52 is provided with a head 53 adapted to be received in the

recesses

25 or 21. The bolts are threaded for reception in nuts 54 arranged in'dovetail recesses 0 55 provided in the inner face of the main weight mmber 30 and of a size substantially larger than the nuts 54. The tightening of the bolts 52 clamps the crank and main weight member together, and after the elements have been assembled, each recess 35 is filled with a molten metal such as lead, as indicated by the numeral 56. This operation makes the nuts 55 substantially permanent parts of the main crank member 36.

A supporting rod for the main weight is arranged at each side of the crank ll. Each supporting rod includes a pair of rod sections 51 connected by a turnbuckle 58, andeach lower rod section 51 is provided with a'hook portion 59 inclined to correspond with the openings 38 and receivable therein. :I'he upper rod sections 51 are arranged in the grooves 22 when the apparatus is assembled, and each of the upper rod sections is threaded for reception in a nut Bil which seats upon the upper extremities of the lugs or ears 2 i As stated, the hooks 59 are arranged in the open-,-

ings 38, and the slots. 35 are arranged at angles corresponding to'the angularity of the supporting rods to receive the lower sections thereof.

Referring to Figures 4; and 9, the numeral 5|! designates a hanger rod, two of which are employed in connection with the apparatus. Each hanger rod is provided at its upper end witha hook 62 receivable in one of the openings i6 of the jack post bearing lugs l5, while the lower ends of 0 the hanger rods are provided with hooks 63 inclined similar to and adapted to be received in the openings 32 of the main weight member.

In Figures 10 and 11 the counterbalance is,

shown in connection with a standard geared speed 5 reducer, and in such use, it will be apparent that the counterbalance weight and the lower portion of the crank lie outwardly of the foundation of the gear reducer when the parts are in the positions shown in Figures 10 and 11. Accordingly,

60 means is provided for supporting the counterbalance weight with respect to the foundation of the speed reducer when it is desired to disconnect the counterbalance from the crank.

The speed reducer, of course, forms no part of the present invention and has been only generally illustrated in FigureslO and 11. The speed reducer unit is indicated as a whole by the numeral 56, and includes the usual crank shaft 65. The

crank and counterbalance shown as being mount- 0 ed upon the shaft 55 in Figures 10 and 11 are identical with the similar units previously described and no further description is considered necessary. It will be noted that the parts of the crank, counterbalance and associated elements 5 are designated by the same reference numerals as employed in connection with the figures previously described.

The speed reducer, as is the usual practice, is mounted upon a concrete or similar foundation 66, and the counterbalance swings in a plane adjacent and parallel to the side or end 61 of the foundation. In place of the hanger rods 6|, previously described, short supporting rods 68 are employed when the invention is used in connection with a speed reducer of the character indicated. Two of the rods 68 are preferably employed, and these rods are supported in the in Figure 12 and is provided with a face plate 13 preferably welded to the socket as at I4.

In building the, foundation 66, the sockets 69 are supported in position while the cement is being poured, and the face plate I3 is arranged flush with the adjacent face 6! of the foundation, as will be apparent. The edges of the face plate I3 may be provided with 90 notches as. indicated by the numeral T5 to assist in accurately locating the center lines of the sockets. The supporting rods 58 are slidable in the socketsand project therefrom as indicated in .Figures 11 and 12. Obviously the supporting rods may be inserted in the sockets after the completion of thefounda- 1 pumping operation is well known and need not be described in detail. It will be apparent that the present construction provides the maximum Weight at the maximum distance from the axis of rotation of the shaft l5. and thus a counterbalance constructed in accordance with the present invention is highly efficient.

When it is desired to release the counterbal ance from the crank ill for any purpose, as when it is desired to clean the well or to change from a pumping to a drilling operation, the releasing of the counterbalance is accomplished with a. minimum of labor and with a minimum expenditure of time. -.To release the counterbalance, the hanger rods 5! are placed in position withthe hooks 52 in the openings l6 of the ears l5, whereupon the lower hooks 53 are inserted in the slots 5 32. At this time, the counterbalance will be in the position indicated in Figure 4, and accordingly the hanger rods will assume an angular tion, as will become apparent, the lower hooks 63'will be arranged in the outer ends of the slots 32.

With the parts arranged as described, the bolts 52 are removed, whereupon the turnbuckles 53 position between the ears I5 and slots 32. .Since the counterweight will be in itsuppermost poslare loosened to tend to lower the counterbalance.

whereupon the weight of the counterbalance will be supported by the hanger rods. The continued loosening of the turnbuckles 58 permits the counterbalance to move further downwardly and 5 rearwardly, until its limit of movement is reached, this limit in the present instance being the point at which the counterbalance engages the jack post to limit further inward movement. All of the weight of the counterbalance at this time will be 10 supported by the hanger rods 63, and the tumbuckles are further loosened to permit their withdrawal.

when all of the weight is released from the supporting rods 51, the upper ends of the sup- 15 porting rods may be released from the ears 2|, whereupon the hooks 59 at the lower ends of the supporting rods may be drawn outwardly. The counterbalance under such conditions will be completely released from the crank I1 and 20 will be supported by the hanger rods Si, and accordingly the shaft l and crank II are free to rotate.

sired purpose, and the counterweight remains in 25 its lowermost position supported by the hanger rod ii. In the present instance, the counterweight is shown as being in engagement with the jack post, and it will be apparent that in installations where there is slight clearance between the counterweight will come to rest upon the foundation before moving inwardly into engagement with the jack post. Moreover, the invention is not limited to use with the apparatus associated with 35 the jack post, but is capable of general installation wherever a counterbalance is required.

When it is desired to re-mount the counterweight, the crank ll is moved to its lowermost or vertical position, whereupon the supporting rods are placed in position by inserting the lower hooks 59 thereof into the openings 38 and then placing the upper ends of these rods into the grooves 22 of the ears 2|. The turnbuckles are then tightened to elevate the counterweight 45 until it is at approximately the correct height with respect to the crank. In this connection, attention is invited to the fact that the counterweight partakes of very little vertical movement and accordingly only a few turns of the tum- 50 buckle are necessary to raise the weight approximately to the proper position. When such position is reached, the center bolt- 52 is in inserted through the center bolt opening 26 of the crank and is threaded into the corresponding 55 nut 54 carried by the counterbalance weight. If necessary, the central bolt 52 may be slightly longer than the remaining similar bolts, and

when the center bolt is tightened by rotating its head 53, the counterbalance will be drawnto- 60 Ward the crank arm and the rib 28 will move into the slot 53. This operation may cause the counterbalance to partake of slight vertical movement with respect to the crank, and the central bolt opening 26 is slightly elongated to 65 compensate for any such vertical movement.

It will be apparent that the initial operation of connecting the counterbalance to the crank takes place with the lugs 28 of-the crank in registration with the corresponding recesses 35 of 7 the counterbalance, and accordingly the lugs 29 move laterally into the recesses 35 when the central bolt 52 is tightened. After the central bolt has been drawn up tight, the" engagement of the rib 28 in the groove 3! and-the engagement of 15 the lugs 29 in the recesses 36 will accurately po- Thus the apparatus may be completely. disconnected from the counterweight for anydecounterweight and the jack postfoundation, the

sition the counterbalance with respect to the crank, whereupon the outer pair of bolts 52 may been illustrated in connection with an oil well apparatus including a jack post assembly, and such an apparatus is conveniently operated by meansof a pitman connected to a crank and secured in one oi the crank openings 20. Since this arrangement is conventional it has not been illustrated in the drawings.

After the apparatus has been placed in operation for a short time it is preferably shut down and checked for tightness, the bolts 52 and turnbuckles 58 preferably being tightened as a matter of precaution, after which continuous operation may take place. It will be apparent that no'shearing forces will be transmitted to the bolts 52 inasmuch as these bolts are necessary only for securing the counterweight to the crank. The weight and centrifugal forces are taken up by the supporting rods 51 and the engagement of the rib 28 and slot 3|, while torsional strains are taken up by the arrangement of the lugs'2l in the recesses 35.

While the crank has been shown as being connected to the counterbalance centrally with respect thereto. it will be apparent that lag or lead may be provided through the counterbalance and crank, when desired. The distance between the recesses is such as to permit the lugs 29 to be arranged in selected recesses instead of being arranged as shown in Figure 1. For example, the lugs 28 may be arranged in the first and third recesses 35 from the left, as viewed in Figures 1 and 6, whereby the counterbalance will lag with respect to the crank when the latter is rotated in a clockwise direction. Similarly the lugs 29 may be arranged in the third and fifth recesses 35 to cause the counterbalance to lead with respect to the crank. Obviously the supporting rod will occupy diirerent positions wherein the counterbalance leads or lags with respect to the crank H. The additional slots It and openings 38 are provided for this purpose, and it will be apparent that the hooks 58 may occupy the first and fourth openings 38 or the third and sixth.openings, depending upon whether the counterbalance is leading or lagging.

The rib it performs several functions in the apparatus. It will be apparent that the'recesses 35, slots 30. and openings 38 extend through the rib 33, and thus this rib functions to provide torque tak'e-up means and'also forms the slots which position the 'lower ends of the supporting rods 51. Moreover, it will be apparent that the main counterbalance Ill isa relatively heavy casting, and the rib 33 serves to prevent, the warping of this member during the castinrho'peration.

The radially outer face of the rib '33 also assists in properly locating the additional weights ll when such weights-are employed. In this connection, attention is invited to the fact that the 'additional weights readily may be attached or '65 counterweight.

detached according to the desired mass of the counterbalance. These weights are made in various thicknesses so that fine adjustment can be obtained and all but the outermost weight are 5 provided with inner ribs 44 and outer slots 45 to properly position the weights and take up the weight and torque thereof. 'The outermost weight is provided only with the inwardly extending ribf 44 since no other weights are secured thereagainst, and the outer Weight is also recessed as at 41 to receive the bolt head 5|.

The weights are preferably made incomplementary sections to facilitate application and removal. When it is desired to add a weight to the main counterbalance body 30. rods are inserted through the end openings 46 of one of the weights 4!, and these rods are then inserted in corresponding openings 40 in the main counterbalance. The free ends of the rods may be lifted and the weight sections moved into engagement with the main body 30, whereupon the bolts 48 may be applied. The corresponding weight section at the opposite end of the counterweight may be similarly applied. The engagement of the lugs and grooves of the additional weights and the engagement of the lug 44 of the innermost weight in the recesses 39 of the main weight member serve to accurately position the various weight members with respect to each other,and these 0 lugs and grooves take up the weight, torque and centrifugal force, as will be'apparent, thus relieving the bolts 52 of any shearing stresses.-

The operation of the form of the invention shown in Figures 10 and 11 is substantially identical with the operation previously described and need not be referred to in detail. The bolts 52 are removed as in the previous case to disconnect the counterbalance 30 from the crank whereby the counterbalance will be wholly supported-by 40 the hanger rods 51. The counterbalance thereupon swings inwardly toward the face Bl of the foundation 6t, and accordingly the counterbalance engages. against the rods 68. These rods have their projecting ends normally arranged slightly below the planes of the slots 32, but it will be apparent that the counterbalance moves downwardly to some extent when it swings inwardly after the removal of the bolts 52. turnbuckles 58 are then loosened whereupon the counterbalance is gradually lowered until the projecting ends of the rods 68 clear the edges of the slots 32. The-counterbalance then moves inwardly against the wall or face, 61 and the counterbalance is supported upon theprojecting ends of the rod-s 68. As soon as all weight is relieved from the hanger rods 51, these rods may be removed, whereupon the crank H is freely rotat able..

The counterbalance may be remounted with respect to the crank inthe manner previously described. The hanger rods til are replaced in position with the hooked lower ends Ell thereof arranged in the openings 38, whereupon the turnbuckles 58 may be tightened to elevate the The counterweight is moved outwardly toward the crank and elevated to the proper position for the replacement of the bolts 58, and after these bolts have been replaced, the counterbalance is again ready for operation.

" 70 From the foregoing it will be apparent that the present apparatus involves numerous advantages over prior constructions. The interlocking relationship of all of the parts provides take-up means for weight, torque and centrifugal force 75 and assures the accurate positioning of the parts The ' with respect'to each other. While the bolts 48 and 52 are adequate to support the weights of the respective parts, it is not necessary for them to perform such function in view of the interlocking relationship of the parts. The supporting rods 51 assistthe rib 28 and groove 3| in supporting the weight and centrifugal force of the counterbalance.

It also will be apparent that mounting and demounting are readily accomplished in a short space'of time with a minimum expenditure of labor. The apparatus requires no special installation. For example, when it is used with standard jack post installations it provides the maximum weight that can be swung and at the same time clear the conventional jack post foundation, and it maintains th usual crank clearance for the pitman, thus requiring no special pitman connection. i

It is to beunderstood that the forms of our invention herewith shown and described are to be taken as preferred examples of the same and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

We claim:

1. The combination of a crank, a weight adapted to be arranged against one side of said crank adjacent its free end, said weight being elongated in a plane at right angles to the axis of rotation of said crank, means for securing said weight and said crank to each other, a supporting rod for said weight anchored at one end with "respect to said crank adjacent the axis of rotation thereof and having means at its other end engaging said weight, a pair of hanger rods adapted to be arranged outwardly of the opposite edges of said crank and having means at their radially outer ends adapted to engage and support said weight, and stationary means for supporting the radiallyv inner ends of said hanger rods, the latter ends of said hanger rods having with said stationary means connections fixing said hanger rods against downward movement.

2. The combination of a crank, a weight adapted to be arranged against one side of said crank adjacent its free end, fastening means pass ng through said crank and said weight, a support ng rod for said weight anchored at one end with respect to said crank adjacent the axis thereof and having a hook at its otherend, said weight having an' opening to receive said hook, said supporting rod including a turnbuckle intermediate its ends, the radially inner end of said supporting rod, with respect to said weight, being laterally offset from its radially outer end, and means for suspending said weight when said fastening means is removed and said turnbuckle is loosened.

3. The combination of a crank, a weight adapted to be arranged against one side of said crank adjacent its free end, fastening means passing laterally through said crank and said weight,

a supporting rod for-said weight anchored at one end with respect to said crank adjacent theaxis thereof and having a hook at its other end, said weight having an opening to receive said hook,

and on opposite sides of the axis of rotation 10 thereof, said rods having hooks engageable with said weights and provided with tumbuckles, the radially inner ends of said rods with respect to said weight, being laterally offset from their radially outer ends, said weight being provided with openings, and hanger elements supported against. downward movement and projecting toward said weight for engagement in said openings when said fastening means and said supporting rods are removed.

5. The combination of a crank, a weight adapted to be arranged against one side of said cra'nk adjacent its free end, fastening means passing through said crank and said weight, a pair of supporting rods, means for supporting one end of said rods with respect to said crank adjacent and on opposite sides. of the axis of rotation thereof, said rods having hooks engageable with said weight and provided with turnbuckles, the radially inner ends of said rods with respect to said weight, being laterally offset from their radially outer ends, a pair of hanger rods having hooks at opposite ends thereof, said weight having slots receiving the hooks at one end of said hanger rods, and stationary ears adjacent the axis of rotation of said crank and provided with openings to receive the hooks at the free ends of said hanger rods.

6. The combination of a crank having an arcuate rib on one face thereof concentric to the axis 40 of rotation of said crank, an arcuate weight adapted to be arranged against one face of said crank andhaving an arcuate groove receiving and fitting said rib, said weight having an integral arcuate relatively heavy rib concentric with said axis and having its radially inner face of a radius substantially equal to the radius of the free extremity of said crank, said integral rib being provided in its radially inner face with laterally extending recesses, said crank being proa vided at its free end with radially extending lugs received in said recesses, bolts passing through said crank and said weight, supporting rods arranged outwardly of the edges of said crank and each provided with a turnbuckle, and means for supporting the radially inner ends of said rods with respect to said crank, the radially outer ends of said rods being provided with hooks engageable with said weight.

'7. The combination of a crank having an arcuate rib on one face thereof concentric to the axis of rotation of said crank, an arcuate weight adapted to be arranged against one face of said crank and having an arcuate groove receiving and fitting said rib, said weight having an integral 65 arcuate relatively heavy rib concentric with said axis and having its radially inner face of a radius substantially equal to the radius of the free extremity of said crank, said integral rib being provided in its radially inner face "with laterally 70 extending recesses, said crank being'provided at its free end with radially extending lugs received in said recesses, bolts passing through said crank and said weight, supporting rods arranged outwardly of the edges of said crank and each provided with a turnbuckle, means for supp rting the radially inner ends' of said rods with respect to said crank, the radially outer ends of said rods being provided with hooks engageable with said weight, said weight being provided with openings, and hanger. elements projecting toward said weight and receivable in said openings to support said weight when said bolts and said supporting rods are removed.

8. The combination of a crank having an arcuate rib on one face thereof concentric to the axis of rotation of said crank, an arcuate weight adapted to be arranged against one face of said crank and having an arcuate groove receiving and fitting said rib, said weight having an integral arcuate relatively heavy rib concentric with said axis and having its radially inner face of a radius substantially equal to the radius of the free extremity of said crank, said integral rib being provided in its radially inner face with laterally extending recesses, said crank being provided at its free end with radially extending lugs received in said recesses, bolts passing through said crank and said weight, supporting rods arranged outwardly of the edges of said crank and each provided with a turnbuckle, means for supporting the radially inner ends of said rods with respect to said crank, the radially outer ends of said rods being provided with hooks engageable with said weight, hanger rods for said weight provided at opposite ends with hooks, said weight being provided with slots to receive the hooks at one end of said hanger rods, and stationary apertured ears adjacent the axis of rotation of said crank to receive the hooks at the other ends of said hanger rods.

9. The combination of a crank, a weight adapted to be arranged against one face of said crank, said crank and said weight having interfltting parts preventing relative movement of said weight in any direction in a plane parallel to said crank, bolts securing said weight to said crank, said weight being provided with an arcuate reinforcing rib projecting from one face thereof and provided with slots extending thereacross, said weight being provided with transverse openings adjacent the radially outer ends of said slots, supporting rods arranged adjacent to the edges of said crank and having their radially outer portions receivable in certain of said slots, the radially outer ends of said rods being engageable in said transverse openings, and means for supporting the radially inner ends of said rods against radial movement, each of said rods including a turnbuckle.

10. Apparatus constructed in accordance with claim 9 provided with a pair of hanger rods having hooks at the ends thereof, said weight being slotted to receive the hooks at the radially outer ends of said hanger rods, and stationary ears having openings to receive the radially inner ends of said hanger rods.

11. The combination of a crank, a weight adapted to be arranged against one side of said crank adjacent its free end, fastening means passing through said crank and said weight, a

supporting rod for said weight anchored at oneend with respect to said crank adjacent the axis thereof and having means adjacent its other end .detachably engageable with said weight upon relative movementof such end of the rod laterally with respect to a face of said weight, said supporting rod including an adjusting device for adjusting the distance between the ends of said rod, a stationary support, and means having with said support a connection fixing such means 2,074,792 against downward movement and having engagement with said weight for suspending the latter when said fastening means removed and said adjusting device is operated to increase the distance between the ends of said rod.

12. The combination of a crank, a weight adapted to be arranged against one side, of said crank adjacent its free end, fastening means passing through said crank and said weight, a

' 10 supporting rod for said weight anchored at one end with respect to said crank adjacent the axis thereof and having means adjacent its other end detachably engageable with said weight 'upon relative movement of such end of the rod laterally 15 with respect toa face of said weight, said supporting rod including an adjusting device for adjusting the distance between the ends of said rod, a stationary support, and a pair of hanger rods adapted to be arranged outwardly of the opposite edges of said crank and having their radially outer ends engageable with'said weight to suspend the latter when said fastening means is removed and said adjusting device is operated to increase the distance between the ends of said rod, each of said hanger rods having with said support a connection fixing such hanger rod against downward movement.

' JOE a. LYNE.

ROBERT GRIFFIN DE LA MATER. JOHN M. COOPER.