US2618173A - Pump rod connecting device - Google Patents

Description

Nov. 18, 1952 R. THOMAS EI'AL 2,618,173

PUMP ROD CONNECTING DEVICE Filed Dec. 2. 1947 s Sheets-Sheet 1 II A f- 1 INVENTORS. EZmerR. Th am as H any L. A ew" M? 9 Ti /gs AGE/V7.

Nov. 18, 1952' v E. R. THCMAS EI'AL PUMP ROD CONNECTING DEVICE 6 Sheets-Sheet 2 INVENTORS. Elmer R Thamas' Harry L .flye BY Q Mai-1v? Filed Dec. 2, 1947 1952 E. R. THdMAs ETAL ,618,

PUMP ROD CONNECTING DEVICE Filed Dec. 2, 1947 6 Sheets-Sheet 5 INVEN TORS. Elmer R. Tb omas Harry L. flj/ers THEIR/162W) Nov. 18, 1952 E. R. THOMAS ETAL 2,618,173

PUMP ROD CONNECTING DEVICE Filed Dec. 2'. 1947 s Sheets-Sheet 4 IN V EN TORS 29 E/merR. 720mm 4 5 Harry L flyers THE R Aazwr Nov. 18, 195 E. 'R. THOMAS ETAL PUMP ROD CONNECTING DEVICE .6 Sheets-Sheet 5 Filed Dec. 2, 1947 I l O 7 I I4 TH RAGE/V7 S. m m m m Harry l. flyem' Elmer/Q. 7710mm:

NOV. 18, 1952 THQMAS E 2,618,173

PUMP ROD CONNECTING DEVICIQ/ Filed Dec. 2, 1947 6 Sheets-Shed 6 INVENTORJ. Elmer R. Thomas By Harry Lfl em Patented Nov. 18,

UNITED "STATES PATENT OFFICE 1 PUMP ROD CONNECTING DEVICE EImer'R ThomaS, Healdton, Okla., and Harry L. Ayers, Wichita Falls, Tex; said Ayers-assignmto said Thomas -Applicationillecember 2, 1947, Serial No. 789,188

: Claims.

. This invention relates .to improvements in pump rod connecting'devices, andmorepa'rticularly to devices which automatically hook-on and hook-oil rod'lines ofpumping wells.

In the pumping ofoil wellsand the like from a central source'ofipower, the, pumping usually is "done by a mechanism, such as a crank or an eccentric, that'impartsza reciprocating movement to'a red line and which crank orleccent'ric is driven by an engine or a motor through speed reducing gearing. The power source usually is so positioned thaticertain wells, are attached to one side of the crank or eccentric by means of their respective rod lines, and others to the opposite side of the crank'o'r eccentric in order substantially to balance the load so' that the engine ormotor has only to overcomefthe friction and to'lift the actual weight of the iluid being pumped.

Wells being pumpedhavedifferent capacities of production, and require pumping at various times for periods of varying duration in order to obtain the maximum production and the maximum ef- "ficiency. To preventundue wear on the equipment when 'the'w'ells' have been pumped off, it has been necessary heretofore,'to have an operator or pumper on'duty all of the time, so that when necessary,..he'could connect the wells to or disconnectthem vfrom the source of, power,

j according to a'pre-arranged schedule or in accordan'ce with the physicalproperties of the various wellsas to production, or, when a well ceases to produce fluid, to hook the well on after sufficient fiuid has filled the reservoir around and adjacent the'working barrel on pump in the bottom of the well. One .pumper frequently. must be responsible for the care of several (sometimes as many as twenty) wells, aswell as the other duties incident to the care .of oil producing property. Consequently, it has notalways been possible for proper time for the most efficient performance or to saveunnecessary wear and tear on equip- -ment, or to make'needed repairs and replacements.

The primary object of. this invention is to provide a mechanism that will ho'ok-.on-a rod line of. a well with a source of power, at a predetermined time, .and to pump the well for a predetermined period of time, which times can be determined by the number of strokes per hour at which the eccentric orcr'ank is ,timed'to' operate.

Another object of this inventionis to provide a mechanism that can be set to hook-off a well automatically for a predetermined period of time,

and the automatic hook-on,T pump,and hook-' ofi cycle can be repeated. indefinitely, orcan be reset to operate on a different cycle for any or all -.of the timenfactor's. H be H vI Still another object or this inventionisto provide a mechanism that is so carefully balanced with the associated parts and'the hook-oilv and hook-on mechanism that the pounding action heretofore encountered in pumping wells, when they become pumped off, will cause the rod line to bedisconne'cted'by the hook ofi mechanism even though the pumping cycle has not been completed. V

.Yet another object of. this inventionis to provide a mechanism that will, make possible the replacing orrepairingofjsections of rod lines without auxiliary ipu'lling implements andwithout serious danger tov workmen.

In the present invention,,the human factor very largely'has beenelim'inated; by the provision of an automatic hook-onand"hook+ofi mechanism. This promotes efiici'ency, and i'curtails injury to the workmen.

Due to the particular balance of the parts associated with the hook-on and hook-off mechanismand to the peculiar characteristics of pumping wells giving-a pounding action when 1 nect the rod line to resume the pumping operation.

Occasionally, rod lines break and require repair or replacement. By removing the broken pull rod from the rod line,"it can be replaced by a new one which has necessitated heretofore the use of come alongs or jacks to loosen or take the slack out of the rod line, so that it may be disconnected or reconnected with the power source before thepumpin'goperationmay be re- 1 sumed.

With the present invention provision is'made "to disconnector'reconnect the'loose rod line, and,

by the propel-manipulation of they various parts, the rod line may be disconnected for repair or may be reconnected or tightened sufficiently so that it may be operated bythe crank-0r eccentric mechanism.

.An embodiment of this invention is illustrated in the accompanying drawings, in which:

Fig. l is a side elevation of the mechanism with the center portion broken away; v

Fig. 2 is a top plan view of the mechanism, as shown in Fig. 1;

.Fig. 3 is a side elevation of. a fhook-ofi or hook-on. pin mechanism in position to receive the rod line for fhook-oni orffor sustaining the weight of the red line;

Fig. 4 is a similar view thereof after the weight of the rod line has engaged the pin to actuate the mechanism;

Fig. 5 is a perspective view of the rod line hook-on or hook-off in removed from the mechanism;

Fig. 6 is a top plan View of the hook-on or hook-off mechanism but with the pin in raised position;

Fig. 7 is a side elevation of the mechanism with the pin in raised position substantially as shown in Fig. 6;

Fig. 8 is a vertical longitudinal section taken on the line 8-8 of Fig. 6;

Fig. 9 is a perspective View, with parts broken away and shortened and other parts removed, of the rod line hook-on and hook-off stirrups;

Fig. 10 is a perspective View of the timing mechanism of the device and associated parts;

Fig. 11 is a cross section taken on the line I I-I I of Fig. 2, showing the clutch arrangement of the timing device;

Fig. 12 is a perspective view of a portion of the frame showing the guide rollers thereon;

Fig. 13 is a top plan view ofthe latch operating mechanism with parts broken away and in section and with the dashed outline showing the mechanism in tripped position; and

Fig. 14 is a side elevation thereof.

With more detailed reference to the drawings, the numerals II designate suitable supports, such as posts which may beembedded in the ground or in concrete and upon which a frame is supported. The frame 2 includes members which may be of any suitable material, such as structural steel, angle iron, or the like, and are secured to the posts II' by bolts 3. A cross member 4 ties the frame members 2 together and is secured thereto, while additional connections may be provided if desired.

Brackets 5 are secured to the frame members 2 and have rollers 6, journaled thereon (Figs. 2 and 12) for supporting and guiding the rods of the mechanism aswill be described more fully hereinafter. Additional guide rollers are shown at I, for the rods and stirrups.

A stirrup 8 at the power end, comprises parallel rods or legs 8', having spaced webs I 0 and II secured therebetween to form openings or eyes therethrough, and a loop end I2 which, with the webs I0 and II and loop end I2, are adapted for engagement with the hook-on and hook-off pin of the mechanism. The legs 8 are parallel with connecting rods I3, and the rods 8' project through and are slidable in a clamp I4 which clamp connects together the inner ends of the rods I3. This clamp I4 is formed by members secured by bolting in binding engagement with the rods I3 but which will permit free sliding movement of the stirrup 8 with respect to the clamp I4.

The connecting rods I3 extend outwardly from the clamp I4, and their outer ends are secured in binding relation by a clamp I5, including members bolted together and which clamp the ends of the rods I3 fixed with respect thereto. A power line stirrup I6 includes parallel rods I'I secured together by a clamp I8 which clamps the ends of the rods H in binding engagement, and which clamp I8 also extends in guiding engagement with rods I3, slidably receiving the latter. The parallel rods U have a series of cross webs I3, and 2| secured therebetween for engagement 4 with a "hook-off pin of the mechanism, as will be more fully described thereinafter.

The parallel legs I! of the stirrup I6 extend outward through the clamp I5 and are freely slidable therein. The rods I I are joined by a closed loop at the outer end of the stirrup I6. The clamp I5 has the midportion thereof cutaway at 22 to receive the rods I I, and these have fixed therebetween a cross bar 23, slidable through the recess 22, as shown in Fig. 9. A pin 25 is inserted through a hole in the clamp I5 and through the hole 24 in the bar 23, when centered with the clamp hole, so as to lock the stirrup I6 and the clamp I5 together for unitary movement of the stirrup and connecting rods I3, during the pumping operation. The stirrup I6 is connected with an end 26 of the rod line.

However, when the rod line becomes disconnected, as by the rods breaking, or when, for any other reason, it is necessary to let out the slack in the rod line 26, the pin 25 is removed so as to permit the stirrup I6 to slide outward. Then, after the rod line has been repaired or it is desired to tighten the rod line, the pick-up mechanism is operated as will be more fully described hereinafter.

Spaced apart and mounted near each end of the frame 2 are hook-off and hook-on devices, generally designated as 21 and 23, respectively, each of which forms a latch connection with one of the stirrups 8 or I6. These devices are identical in structure and like reference characters will designate like parts on the two devices, except the numerals designating the various parts of ,the hook-on device 28, will be primed The hook-off device 21 (Figs. 3 to 8) comprises a base 29 which is secured to the cross member 4 by bolts 30. This structure has sufficient strength so that it will not yield as a result of the weight of the rods 26 being applied thereto when the rods are hooked-off. The base 29 has a pair of upstanding ribs 3I thereon, between which a central bifurcated lever 32 is mounted. The lever 32 is pivoted at 33 to the upstanding ribs 3I, and has a hook-off pin 34 pivotally connected thereto by a bolt 35. A bifurcated end 36 is integral with hook-off pin 34 and extends upward at an obtuse angle thereto. The end 36 is connected with links 31 by a pin 38 passin through slots 35 in the links 31.

The opposite ends of links 3! are pivotally connected together by a pin 40. The pin 40 also pivotally connects together levers AI and links 42, and extends through a $1013.43 in a link 44 to limit the travel of the pin 40. The levers 4| are secured rigidly. as by. set screws, to a shaft 45 that extends laterally of the device and to which an operating arm 46 is also secured. The shaft 45 is journaled in the upstanding ribs 3I to permit the levers 4| to swing about the axis of the shaft 45.

The links 42 have the upper ends thereof pivotally connected by a pin 41 to counterweight lever 48. The lever 48 is mounted between the bifurcated portions of up-turned ends of the lever 32. A pin 49 connects together the upper end of the lever 32 and the end of the lever 48. The lever 48 has a weight 59 adjustably mounted thereon for adjustment along the length thereof and secured thereto by av set screw 5|, which weight gives the proper counterbalance to the pin 34.

The link 44 is pivoted on a bolt 52, which bolt 52 is carried by theupstanding ribs 3I. With the device, as shown in Fig. 7, the pin 34 is in iraise'd position, and it 'is 'now so positioned with respect to the pivot centers 38, 40, 4'1," 49, that fthew'ei'ght 50 overbala'nces the pinand keeps this pin in raised position. However, byshifting the arm "46 to the opposite side,as*shown in-Fig. 3,

[the pin34 isdropped intoan inclined position forwardbut since the pivot point-'40 has shifted to the opposite side of the dead 'c'enter position between the pivot points 45 and "41, as shown in Fig. 3, the pin 34 is so shifted with respect 1 to the fulcrum points that the pin-34 overbalances the weight '50 and the device will remain'in this iposition until positively moved bythe stirrup into the pos'ition shown in the lowerportion'of Fig.

11', and also in Fig. 4.

The positive swinging movement of the pin '34 bythe stirrup acts through the links 31 to shaft the toggle4I-42' to its opposite position,

with the fulcrum points back in substantially the same relative positions as shown in Fig. "7, except that the pin 34 is being held in binding engagement against transverse supp'orting'member by the weight of the rods 26, which are attached to the pump jack of the well.

The hook-on device 28 is operated in like manner. As the pin 34 of the device 21 engages the position as shown in the upper portion of .Fig. 1, thereby disconnecting the rod'line to the well.

It will be evident that duringpumping of the well, the power motion is transmitted from the .power line 1, through the stirrup8, the latch pin .34, and clamp I4 to the connecting rods l3 to reciprocate said connecting rods, as shown at the top in-Fig. 2, The opposite ends'of the con- 'i-necting rods 13 transmit motion through the clamp l5, pin 25, bar 23, and stirrup I6, to the pump rod line 26. The heads on the outer ends "of the connecting rods l3 limit the outward -movement of the clamps l-4 vand IS with respect thereto.

During this pumping action, the hook-01f pin 34 is disengaged from the stirrup I6, as shown in Fig. 7.

hook-off pin 34, as shown in Fig. '1, this will lock the stirrup l6 in a holding position, while However, upon engagement of the the stirrup 8 will reciprocate with respect thereto, its hook-on pin 34, then being released, as

shown in Fig. 1.

Mounted at the forward end of the frame 2 I is a power take-off mechanism comprising a lever ,6], which is attached to a shaft 62.

Theshaft 62 is connected with an over-runn n clutch, generally designated at 63, connected thereto, and the over-running clutch .63 has a gear 64 connected therewith to be driven thereby. The shaft 62 is journaled in a bearin 65 'so that the lever 6! will protrude downward between arms 66 and The arrn-BG is adjustably'attached to the inner end of the stirrup 8 for adjustment lengthwise thereof and the armG'I is adjustably-secured to the arm 66. The lever-Eli is, positioned :between the outturned portions: of the arms '66 an'dufi! (see Fig. 10) ,so thatupon reciprocation of "the rod 1 and the stirrup18, a rocking motion is imparted *to the lever 6 I which in" turn rotates the shaft 62' throughan ar'cuate move'ment. In sol-doing,

gar-signs the rollers 53a alternately disengage and engage j cam faces 63b (Fig. 11) ,soas'to rotate the gear 64 in one direction stepby-step.

This gear 64 in turn rotates a 'large gear 68 I which is securedto-a shaft ,69' in-mesh therewith.

' pins 14 and 15" protrude inward and outward,

'pivot bolt 83. v the upper portion of the cover 11 by a pivot bolt 5 at one end, and a pivot bolt 86 at the other end of the link 84 with the outer end of the slidrespectively from the chain 12, as shown in Fig. 2. The pins 14 are adapted to engage'the arm 46,

while the pins 15 are adapted to engage an arm "76 (Figs. 13 and 14) whichispivotally-attached to a cover 11 by a pin Tl. The'arm'lfi has a weight 18" on an outwardlyextending angular portion 79 thereof. The arm 16 has a link 80 attachedthereto, which link 88 is also attached to a link-'8 I. The link 8] is attached to a slidable member '32 intermediate the ends thereof, by a A link 84 is pivotally secured to able member 82.

The purpose of this linkage arrangement is to movethe outstanding finger 81 of the slidable member 82 into and out of operating position relative to' the cover 11, so that it will disappear the upper edge of the cover 1! when the lever 16 is moved by the pin '15, which pin will move the lever 76 from the position as indicated in full outline in Figs. 13 and 14, to the position shown in dotted lines therein. In so doing, the projecting finger will movetransversely outward and longitudinally along the inner edge of the cover 11, and engages an arm 46, mounted on the shaft 45'. 'In so doing, the finger 81 will move the'arm 46 from the position indicated in Fig. 1 to a position substantially like that shown in Fig. 3.

Then, upon outward movement of the stirrup 8, the pin 34', which is positioned outward and at an angle, as in Fig. 3, will be engaged by a web IOto bring thepin 34 into binding engagement with the clamp 14. Since-the clamp I4 is in binding engagement with the rods I 3; the "rods l3, clamp l4, and stirrup'8 will move'in unison. However, as soon'asthe finger'8'i has moved the arm 46' to move the'mechanism into the position shown in Fig.- 3, the pin'l5 will passover the end of lever 'li-asindicated by the dash outline of thechainTZ in Fig. 14, and the weight 18 will cause the lever 16 to'returnto the'position as indicated in full outline in Fig. 14.

When; it is returned to thisposition the finger 81 is retracted and will permit freedom of movement of the arm 46 along the side of the cover 11, so it may return to the position as shown in Fig. 4, when theweblO of the stirrup 8 engages the pin 34-, which engagement shifts the pin'34 from the position shown in Fig. 3 to that shown in Fig. 4, and likewise, shifts the pivot points to the position shown in Fig. 4. However, the

' the frictional engagement of the web l0 and the clamp l4, and, onthe inward movement of the stirrup 8 and rods l3, the bar 2| will be moved inward. This will loosen the frictional hold on the pin 34 of the device 21, and since the hook-off mechanism 28 is in the position substantially as shown in Fig. 4, the weight 50 overbalances the pin 34 and lifts it into the position shown in Fig. 7, upon hooking-off at the rod line 26, to stop the pumping of the well.

The timing of the device is accomplished by inserting a hook-off pin 14 and a hook-on pin 15 in the chain 12 at predetermined intervals and positions, and with the chain 12 geared to travel a given lineal distance in a given length of time. The pumping operation of the well can be so timed according to the number of pumping actions per minute, that the well may be made to pump any desired length of time, as for instance, from fifteen to twenty-four hours, and hookedoff for any length of time, as from fifteen to twenty-four hours, considering the chain 12 to have made a complete cycle in twenty-four hours.

As a result of the operation of pull rod lines on oil producing properties, these pull rod lines occasionally break or become separated, which allows the plunger rods of the well to drop. Since the weight of the pump plunger rods may be several thousand pounds, it is necessary, in order to repair or replace pull rods, to disconnect the pull rods from the power unit to relieve the pull rods of the weight of the plunger rods. When the repairs havebeen made, it is necessary to tighten the lines leading to the pump jack and to reconnect these to the source of power.

With the present invention, the slackness in the rod line may be taken up or let out without the use of jacks or other type of winch mechanism.

When the rod line 26 breaks or becomes disconnected, the rod line will have to be slackened by disconnecting the pins 34 and 34, at which time the rod line may be repaired or a new rod used to replace the broken rod. Upon disconnecting the pins 34 and 34' from the stirrups l6 and 8, respectively, the stirrup l6 and rods 13 are moved outwardly by the weight of the attached plunger rods. It is now necessary to pick up or retighten the rod line 26 in the following manner:

After the repair has been made, and the stirrup I6 is extended outward to the furthest limit, by the pin 34 of the device 21 being raised to the position substantially as shown in Fig. 7, and with the rods l3 disconnected from the device 28 by raising the pin 34' to the position as shown in Fig. '7; sufiicient slack will be permitted in the rod line to make possible the repair or replacement and reconnection of the rod line 26. After the repair has been made, the pins 34 and 34' of the devices 21 and 28 are dropped into the cooked positions as shown in Fig. 3. With these pins so positioned, and with the rod line 1 and stirrup 8 moving inward relative to the rods l3, the pin 34 will engage loop I2 so as to draw the rods l3 and stirrup I6 inward. Th pin 34 will ride over the web l9, and on outward movement of the rods 26 the pin 34 will engage the web l9 and suspend the weight of the rods 26 against the cross member 4 which will arrest the outward movement of the rods [3. With the movement of these rods arrested, and with the stirrup 8 slidable within the clamp [4, upon the outward stroke of the rod 1, the pin 34 will ride over the web I, at which time the rod 1 will reverse its direction and move inward. In so doing the web ll will bring the pin 34' into to move inward.

binding engagement with the outer face of the clamp [4, which will move the clamp I4 and the rods l3 inward a sufficient distance to cause the pin 34 of the device 21 to ride over the web 20,

at which time the rod 1 again will reverse its travel and permit the rods [3 and stirrup Hi to move outward, causing the web 20 to engage with the pin 34 and move the pin into binding engagement with the inner face of the transverse clamp 4.

Upon reversal or outward movement of the rods I3, these will be engaged and held by the pin 34 against outward movement, and the rod 1 and stirrup 8 moves outward and slidably through the clamp l4, which will permit the pin 34 to ride over the web [0, shown in Fig. 2. Upon the movement of the pin 34 over this web It]. the rod i will reverse its movement and start In so doing, the web ID will engage the pin 34' and move it into binding engagement with the clamp M. Then upon continued inward movement of the rod 1 and stirrup 8, the clamp H3 and rods 13 will be drawn inward until the pin 34 of the device 21 will ride over the web 2!, substantially as shown in Fig. 2. At that time, the rod 1 will reverse its movement and start to move inward. At this point the well has been picked up and the rods put into operation substantially as has been described hereinbefore. The pumping will continue until such time as the pin 14 engages the arm 4%, causing the pin 34 to be lifted first to the position shown in Fig, 3, and then to the position shown in Fig. '7 for hooking-01f the rod line as above described.

Each time the stirru [6 moves outward causing one of the webs I9, 2:: or 2| to engage the pin 34 in the position as shown in Fig. 3, and move it into the position shown in Fig. 4, and the arm 46 is moved from the position as shown in Fig. 3, to that shown in Fig. 4, the linkages and center of the toggle 4i and 42 are shifted so that the pin 34 would be lifted upon the slackening of the web 19, 28 or 2| from frictional contact with pin 34. Therefore, the arm 46 has to be returned from the position as shown in Fig. 4 to the position as shown in Fig. 3, each time after the weight is released from against the pin 34, so that the pin 34 will ride over the bars properly during the successive steps used in picking up the rod line 26. Likewise, the arm 48 has to be returned from the position substantially as shown in Fig. 4, to that shown in Fig. 3, each time after the weight is released from the pin 34 from the loop IE or Webs l9 and H, so as to shift the linkages to permit the pin 34 to ride over one of the bars and to shift the toggle center of the linkage device 28, substantially as described for the mechanism 27. By the reversal of the above steps, the rod line 25 may be let out or slackened for repair, etc.

The entire unit may be provided, if desired, with a cover thereover, to protect the operating parts from the weather.

The invention has been described primarily as to the automatic operation thereof; however, it is to be understood that by the manual operation of the arms 48 and 46', the rod line 26 may be hooked off or hooked on by the respective operations. The picking up of the rod line may be done by manually operating the arms 46 and 46 as described above or the weight 50 may be moved inward toward the fulcrum point until the operation is accomplished, after which time the weight may be reset to the correct point so that the lever 48 or 48' may raise the pin 34 or pin 34' automatically upon releasing of the weight and friction contact with members 4 and M respectively.

While the invention has been illustrated in one embodiment, it is recognized that variations and changes may be made therein, without departing from the invention, except as specified in the claims.

We claim:

1. In a pump rod connecting device, the combination of power and pump rod sections, a connecting section, and a toggle action slide bolt latch device for connecting one of the power and pump rod sections with the connecting section, after a predetermined number of strokes of the power section.

2. In a pump rod connecting device, the combination of power and pump rod sections, a. connecting section, and toggle action slide bolt latch means for connecting one of the power and pump rod sections with the connecting section, after.

a predetermined number of strokes of the power section.

3. In a pump rod connecting device, the combination of power and pump rod sections, a connecting section, and toggle action slide bolt latch means for attaching the connecting section with one of the power and pump rod sections and constructed for connection during operation of the power section, after a predetermined number of strokes of the power section.

4. In a pump rod connecting device, the combination of power and pump rod sections, a connecting section, means for anchoring the pump rod section during reciprocating movement of the power section relative thereto, and weight actuated toggle action slide bolt latch means for attaching the connecting section with the power section during operation of the power section, after a predetermined munber of strokes of the power section.

5. In a pump rod connecting device, the combination of power and pump rod sections, a connecting section, means for anchoring the pump rod section during reciprocating movement of the power section relative thereto, and latch means for attaching the connecting section with the power section during operation of the power section, said power section having cross members connected therewith, a trip means comprising a pair of pivoted levers connected together and interconnected with a pivoted latch bolt so as-to engage said cross members step-by-step and to be locked therewith automatically during operation of the power section.

6. In a pump rod connecting device, the combination of power and pump rod stirrups, each having spaced rods with longitudinally spaced connecting webs therebetween, a connecting section including spaced rods slidably mounted relative to the power stirrup, means for connecting said rods with the pump rod stirrup, a latch device for each of the stirrups including trip means and a pin connected therewith, said pin being in position to ride over and successively engage stepby-step the webs, and means for locking the pin in engagement with one of the webs.

7. In a pump rod connecting device, the combination of power and pump rod stirrups, each having spaced rods with longitudinally spaced connecting webs therebetween, a connecting section including spaced rods slidably mounted relative to the power stirrup, means for connecting said rods with the pump rod stirrup. a latch device for each of the stirrups including trip means and a pin connected therewith, said pin being in position to ride over and successively engage step-by-step the webs, and means for locking the pin in engagement with one of the webs, the latch device for the pump rod stirrup having the pin arranged to lock said stirrup in holding position while the latch device for the power stirrup is released and the connecting means is disconnected.

8. In a pump rod connecting device, the combination of an endless chain timing device having timing lugs thereon for the connection of power and pump rod sections, each having a, rod, longitudinally spaced cross members thereon, a connecting section including a rod slidably mounted relative to the power member, a latch device for each of the power and pump rod members and including trip means and a, pin connected therewith for actuation by said endless chain timing device, and means for locking the pin in engagement with one of the cross members.

9. In a pump rod connecting device, the combination of an endless chain timing device having timing lugs thereon for the connection of power and pump rod sections, each having a rod, longitudinally spaced cross members thereon, a connecting section including a rod slidably mounted relative to the power member, a latch device for each of the power and pump rod members and including trip means, and a pin connected therewith for actuation by said endless chain timing device, and means for locking the pin in engagement with one of the cross members, and the latch device for the pump rod member having the pin arrangement to lock said member in holding position while the latch device for the power member is released and the connecting means is disconnected.

10. In a pump rod connecting device, the combination of pump and power rod sections, a connecting section, a base mounting said sections, a pair of shafts journaled on said base, the axis of the respective shafts being in alignment, a chain sprocket mounted on each of said shafts, a chain extending around said sprockets in driving relation, clutch and lever means for rotating said sprockets connecting one of said rod sections for rotation of said sprockets upon reciprocation of said rod section, and slide bolt latch means for connecting one of said pump and power rod sections with the connecting section after a predetermined number of strokes of said power section.

ELMER R. THOMAS. HARRY L. AYERS.

REFERENCES CITED The following references are of record in the file of this patent UNITED STATES PATENTS Number Name Date 1,964,909 Garity July 3, 1934 2,123,052 Kearsley July 5, 1938 2,134,615 Lamb Oct. 25, 1938 2,136,452 McKinney Nov. 15, 1938 2,175,651 Thomas Oct. 10, 1939 2,210,172 Landrum Aug. 6, 1940 2,225,252 Auld Dec. 17, 1940 2,256,117 Keeley Sept. 16, 1941 2,283,110 Wagner May 12, 1942 2,320,051 Robinson May 25, 1943 2,334,943 Miller Nov. 23, 1943 2,382,052 Gray Aug. 14, 1945

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