US2170184A - Rocker arm - Google Patents

Description

Aug. 22, 1939. .1. F. CAILLOUX ET AL ROCKER ARM 2 sheets-sheet 2 Filed March 4, 1937 I} John F. Coilloux Philip M. Rea INVENTORS ATTORN EY Patented Aug. 22, 1939 UNITED STATES PATENT OFFIQE ROCKER ARM John F. Cailloux and'Philip M. Rea,

Oklahoma City, Okla.

Application March 4, 1937, Serial No. 128,952

11 Claims. (01. 74-559) The invention relates to rocker arms used as Figure 7 is a longitudinal sectional view taken means for actuating a valve rod from a reciproin a plane indicated by the line 1-4 of Figure 2. cating piston rod. Like characters of reference designate like The present design is primarily intended for parts in all of the figures.

5 use in connection with oil well slush pumps of a Referring now more particularly to Figure 1 5 type consisting of a power piston and chamber of the drawings, the reference numeral I indiand, spaced therefrom and in alinement theree cates as a whole the power end or unit of. a pumpwith, a pump piston and chamber, the twopising organization, the pumping end or unit of tons being connected by a piston rod, and the which is indicated by the reference numeral 2.

power chamber being equipped with a control The two units I and 2 are usual, and each com 10 valve for regulating flow of a power fluid to and prises a piston chamber and a piston therein, the from the chamber. The rocker arm together two chambers being in axial alinement and the with a crank act as a driving connection from two pistons being connected by a piston rod 3. the piston rod to a valve rod which is usually The power unit I is, as usual, equipped with a mounted for reciprocation upon an axis parallel power fluid control valve, not shown, adapted 15 with that of the piston rod. to be operated by the reciprocation of a valve The prime object of the invention is the prorod 4. The units I and 2 are held in their alined vision of a connecting structure between the two and spaced positions by a brace or bridge 5 rods which will be sufficiently flexible to elimiwhich is integral with and supports an upstandnate tendency to bind and at the same time will ing bracket 6 journalling a rockshaft I. The 20 positively drive the valve rod in an opposite dihidden end of the rock-shaft is keyed to a perrection and in proper timed relation with the pendicularly extending crank-arm, not shown, motion of the piston rod. and the free end of the crank-arm is pivotally Other objects of the invention are: the proconnected to the free end of the valve rod 4.

vision of a mechanical structure of the class de- Consequently, rocking motion of the rock-shaft 25 scribed which absorbs practically all of the shock I causes reciprocation of the valve rod 4 in an occasioned by reversing direction of movement of obvious manner.

the two rods, thus obtaining a smooth operation The structure described in the above paragraph devoid of jar and clatter; which permits a free is usual in the art. rotation of the two pistons, thus avoiding to a The device of the present invention is best 30 great extent the scoring of the chamber walls shown as a whole in Figure 2 of the drawings, and and wear upon the pistons; which may be readconsists substantially of a piston rod coupling ily disassembled for replacement of worn parts; structure A, a female telescoping arm element which lends itself easily to adaption upon many B, and a male telescoping arm element C therestandard makes of slush pumps now in general above. 35 use; which is sturdy and durable; and, which is The element C consists substantially of a biefficient in accomplishing all of the purposes for furcated head having parallel upstanding walls which its use is intended. l0 and II connected at their lower portions by In the drawings: an integral floor I2 the upper surface of which Figure 1 is a side elevational view of a pump is preferably arcuate. Integral with and depend- 40 unit with the preferred embodiment of the rocker ing from the floor I2 is a tubular plunger I3 havarm thereon; ing a plurality of lateral perforations I4, the

Figure 2 is a perspective view of the device office of which will be more fully described herewith portions of its connecting members being inbelow. The floor I2 is perforated as indicated removed; at I5 to form a continuation of the bore in the 45 Figure 3 is a perspective view of the annular plunger l3. bearing housing; Depending from the nether surface of the floor Figure 4 is a fragmentary sectional view taken I2 and surrounding the plunger I3 in spaced resubstantially in a plane indicated by the lines lation to the exterior surface thereof is a guard 4--4 of Figure 2; sleeve I6. The ofiice of the sleeve I6 Will be more 50 Figure 5 is a fragmentary detail of a portion fully described hereinbelow. of one of the yoke legs; The head is provided with fluid inlet bores I? Figure 6 is a partial longitudinal sectional which communicate from the exterior of the sides view taken in a plane indicated by the line 66 If] and II to the bore of the plunger I3. of Figure 2; and, Pivotally mounted between the walls I0 and II 6:3

- tubular shell 30 open at both ends.

of the head upon a pivot pin or bolt I8, is a block I9 which is bored to receive the shaft 1 to which it is keyed.

The piston rod coupling structure A consists substantially of an all-thread nipple 20 having an exterior annular shoulder 2| against which is seated an annular shock absorbing ring 22 of a suitable resilient material. A heavy sleeve 23 surrounds the exterior surface of the nipple 2D and the nipple is permitted free rotation therein. A second and similar shock absorbing ring 22 is seated against the end of the sleeve 23, and it will be noted that portions 24 of the sleeve surround and confine the rings 22. Intermediate its ends the sleeve 23 is equipped with two oppositely disposed perpendicularly outstanding trunnions 25 having their ends exteriorly threaded.

It is common practice in the art to construct the piston rod 3 in two sections, the adjacent ends of the sections being threaded to receive a coupling. In the present instance the two piston rod sections are threadedly engaged within the nipple 28 instead of within a usual coupling. A lock-nut 26 is provided around the piston rod to lock the rod and the nipple 26 against, independent rotation, while a jam-nut 2? acts in a similar manner at the other end of the nipple. However, the jam-nut 21 has the additional function of compressing a follower 28 against the ring 22 for anchoring the two rings 22 and the sleeve 23 against longitudinal movement with relation to the nipple 26. The follower 28 has an inwardly projecting flange 29 which is impinged between the jam-nut 21 and the end of the nipple 20 to prevent over compression of the two rings 22. It may be seen that the shock of any force exerted upon the sleeve 23 in a direction longitudinal thereof must be borne by the two rings 22. It will also be noted that while the sleeve 23 "1 is positively held against longitud nal movement with relation to the nipple 2B, and consequently with relation to the piston rod 3, the nipple is at all times free to rotate within the sleeve.

The arm element B con-ists substantially of a The shell is equipped with a closed bottomed removable liner 3! held in place within the shell by a pin 32. The liner 3| is of a diameter sufficient to make a comparatively loose working fit about the plunger [3 which it receives, and the exterior diameter of the shell 38 is sufficiently small to barely pass within the sleeve 16 of the arm element C.

The lower end of the shell 30 is bifurcated to form a yoke 33 consisting of two oppositely disposed legs 34 identical in form and having a sufficient spread to envelope the sleeve 23 transversely. The free or lower ends of the legs 34 are each in turn. bifurcated to form tines 35, and between the tines on each leg is a bore 36 (Figure 4) adapted to receive a bearing housing ring 3?, Usual roller bearings 38 are confined within the ring 3? upon an annular race 39 which closely fits around the trunnion 25.

As a means for holding the ring 3'! against rotation within the bore 36, the exterior surface of the ring is provided with a cavity or perforation 40 adapted to seat a lock-ball 4|. The comparative size of the cavity 40 and the lock ball ii are illustrated in dotted lines in Figure 3. A superficial bore or groove 42 (Figure is machined into one of the tines 35 to permit passage of the ball as the bearing is pressed into operative position around the trunnion. A suitable lubricating connection (Figure 4) is provided for the injection of a lubricant to the bearing members. A washer A3 and castellated nut 44 act to hold the bearing in place and also to hold the yoke in place upon each trunnion. A clamping bolt 45 extending through the tines 35 acts to draw them into firm engagement with the bearing ring 37.

In operation, it will be understood that the distance between the axis of the piston rod 3, represented by a line 55 (Figure 6) and the axis of rotation of the rock-shaft 1, represented by a line 50 (Figure 6), is at all times constant. The device in its operation must move through positions represented by lines 52, which causes a longitudinal slippage between the plunger l3 and the shell 39. A liquid, for instance oil, is introduced into the bore of the plunger through one of the passages H, and during operation the liquid has a dampening effect sufiicient to give a stabilized pressure within the male and female arm elements. The transverse bores M in the plunger together with the loose Working fit between the plunger and the liner 3i permits flow of the liquid from the interior of the plunger to the interior of the shell. The opening H5 in the floor l2 of the head precludes the occurrence of a liquid lock between the shell and the plunger. The sleeve l6 acts as a. protecting agent to prevent the entrance of foreign substances into the cham-- ber complementally formed by the plunger and the shell.

It has been found in operation that there is usually some little end play in the rock-shaft I, particularly when a battery of two complete pumping units are connected by two rocker arms to a single rock-shaft. This is the reason for pivotally mounting the block H) in the head of the element C. The permitted pivotal movement of the block i9 upon the bolt i8 is illustrated in Figure 7 by lines 53.

We claim:

1. The combination with a piston rod, and. with a rocker arm for transferring motion from the rod to another mechanical element, said rocker arm consisting of two slidably connected members, of connecting means between the free end of one of the members and the rod whereby the rod is permitted rotation yet is held against longitudinal movement with relation to the arm, and means for rockably connecting the free end of the other member to said mechanical element.

2. Organization as described in claim 1, in which the rocker arm includes two telescoping elements.

3. Organization as described in claim. 1, in which the rocker arm includes two telescoping elements complementally forming a chamber for retaining a fluid, and a fluid in the chamber for dampening relative movement of the members.

4. The combination with a piston rod, and with a rocker arm for transferring motion from the rod to another mechanical element, said rocker arm consisting of two telescoping members, of a connecting means between the free end of one of the members and the rod whereby the rod is permitted rotation yet is held against longitudinal movement with relation to the arm, and means for rockably connecting the free end of the other member to said mechanical element.

5. A rocker arm for transmitting motion from a piston rod to another mechanical element, said arm including: two telescoping members one member rockably connected to the rod, and the other having operative connection with the mechanical element, said members complementally forming a chamber for retaining a dampening fluid.

6. A rocker arm for transmitting motion from a piston rod to another mechanical element, said arm including: two telescoping members one member rockably connected to the rod, and the other having operative connection with the me-- chanical element, said members complementally forming a chamber for retaining a dampening fluid, and a fluid in the chamber for dampening relative movement of the members.

'7. The combination with a piston rod, and with a rocker arm for transferring motion from the rod to another mechanical element, of connecting means between the arm and the rod whereby the rod is permitted rotation yet is held against longitudinal movement with relation to the arm, and shock absorbing means carried by the connecting means for dampening the shock of any force delivered in a direction longitudinal of the rod.

8. The combination with a piston rod, and with a rocker arm for transferring motion from the rod to another mechanical element, of a unitary connecting means between the arm and the rod and. separable from both, and a shock absorbing means carried by the connecting means for dampening the shock of any force delivered in a direction longitudinal of the rod.

9. The combination with a piston rod, of a rocker arm for transmitting motion from the rod to another mechanical element, said arm including two telescoping members complementally forming a chamber for retaining a dampening fluid, connecting means between the arm and one of the members, and a shock absorbing means for dampening shock between the member and the rod of any force delivered in a direction longitudinal of the rod.

10. The combination with a piston rod, of a rocker arm for transmitting motion from the rod to another mechanical element, said arm including two telescoping members complementally forming a chamber for retaining a dampening fluid, and a fluid in the chamber for dampening relative movement of the members.

11. The combination with a piston rod formed by two axially aligned elements with their adjacent ends adapted to be connected together for simultaneous movement, and with a rocker arm adapted to be connected to the two elements for transferring motion from the elements to a mechanical arrangement, of a unitary means for connecting the adjacent ends of said elements together and for removably attaching them to the rocker arm, and a shock absorbing means carried by the connecting means for dampening the shock of any force exerted in a direction longitudinal of the rod.

JOHN F. CAILLOUX. PHILIP M. REA.

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