US1979348A - Valve operating mechanism - Google Patents

Description

Nov. 6, 1934. R. c. RUSSELL.

VALVE OPERATING MECHANISM Filed June 18, 1932 2 Sheets-Sheet l ai w WMA, w .h l l.- l Il OO. I. mm w my. l-

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NOV. 6, 1934. R, C. RUSSELL 1,979,348

VALVE OPERATING MECHANI SM Filed June 18, 1952 l 2 Sheets-Sheet 2 INVENTOR @08E/'f7' C. RUSSELL ATTORN EYS Patented Nev. e, 1934 unir a .x-sfT-*A-f'ras .ff-PATENT fwn-Fics f imams f VALVE UPERATING fMECHANISM 'a ,Robert C.' Russell, DallasgTex. Application .meia 193s; smal Normanni ritzsiclaims. (oliLina-zalm This invention relates to valveyoperatingmechanism or valvelifters-ior user-primarily incon- Land'rockernarmsfof theV hydraulic type.

nection with. internal combustion-engines and they like, andomore particularly to Whatfmay be `termed automatically compensatingfor self. adjusting rocker arms constituting a principalifpart osad mechanism. i

`ln general,thisinvention seeks to produce` a practical formr oi. oscillating .valve lifter 1means or rocker arm, novel and ruggedl iny its construc- Mtion, `subject to minimum wear, .quiet and positive iny its` automatidv compensation function, comprising fewy parts, and which `can be :pro- `.ducedso economically as to justify its use gent erally on all types-.oiiengines employingrocker arms asa part of thefvalve actuating mechanism. im` object of; this` inventionisto produce novel `self adjusting rocker. arms for use in connection with internal combustion engines fory actuating `the valves thereof in relation totheir seats. This rocker arm` means, according to my1invention, .automatically maintains a `11o-:clearance operating relationship or4 engagement between `all `connections and parts Y of the -valve operating ,mechanism interconnected betweenthe engine or -machine driven cam and `the `valveseat inlthe cylindeig; maintaining said rio-clearance regardless :of `operating rconditions occasioned by .variations in` temperature and length ofthe .val-ve operating parts. This promotesy engine: speed, performance andefficiency byvirtue of improved Yvalve timing \Which is `held. constant, avoids harmful impact or hammering and Wear Vbetween all parte including the valve seatsand therefore eliminates noise and vibration. Such a 4noclearanceoperating engagement .for all parts, as afforded by this invention savesfrequent manual adjustment and engine repair, and affords scitness yof valve closing` and smoothness in .operation for `the life of the engine or machine.

i The necessityV for a` solution of. the Problem involved is pronounced, .especially so` in` present clay high speed internal combustion motors which dependen precisely accurate fandiconstantly .uni-

o form .valve timing for .maximum engineefiiciency.

En aviation i engines especially, which `employyery `substantial valve `operating clearances,r the solution oi the problem isoi outstanding importance and attains increased engine `power andspeed, avoids valve trouble and promotes safety.

`A further objectisto produce av-newform of silent :and self adjustingorocker arm-tot` acme- .chanical `type Whiohffunctions- Without thenccessity ci an` oil cushion or other liquid .i supply. Hence the invention is distinguished inthis further respect ifrom valve operating mechanism How- -ever,-lubrioation; `as such, is an aid to smoothness ,t ine the`;operation.oi my compensating or self `adljusting Vmechanical mockerarms.

.An outstanding object -o my invention-is to uproduce a rocker-arm 'means which lautomatically compensates in two directions, i. e., for expansion, contraction and Wear of `all the valve `operating parts With-their bearings and connections, from @and including the valve seat itselfto and including` the cam and camshaft. To iattain this end, ail-main object isfto mount the rocker arm on an automatically adjustable or compensating bearing .means which .iscoordinated with Imeans for ipositivelyeimparting a rotative yadjusting. move- .ment to saidfbearing, .first in one direction and then the-other; whereby i the 'rocker y'ar-m auto- .matically relieves itself ofeithercrainped or loose position, 'by snuglyresettng itselfto accommodateleither av longer or shorter Yvalve stem and/ or push rodworfother lparts as they vary in length duringoperation.

y Theinvention comprehends the use of a posi- :tively driven mechanical means for transmitting an adjusting or freeing movement from any con- -venientsource-of motion to the `compensating ,bearing toactuate it inione direction tofdeilnitely ease-,ordres it andtherocker arm from crampingnorsundue tightness, together With a torque spring-for 'urging-said bearing in the other directiontoreset .it andthe rocker armto'their `normalno-clearance engagement with and in relation-to all other elements roi the operating tcombination,4 and 'finally' aflooking or clamping imeanscwhich positively grips and xes the bearing.- and its-rocker: arm` together against relative motion softheyoscillate as a unit when `actuating theuvalve from-.its seat, these stated operations beingfpreciselyti-mecl to start `and nish their full cycle while the valve-is on its seat and;` the rocker -arm-isidle. `My invention comprehends assim- `ple construction of practicallymnonmore parts 'than' conventional rocker.Y arms a rnovv in use f for executing .the A foregoing complete `compensating cycle by 4eiiectingfall three functions tc-Wit, freeing, resetting,.and locking, during the period the heel `oitheengine cam -is idly traversingfthe Voperating. means. i

."Pursuantto the foregoing, itis an object and point of novelty in this inventive concept to produce a self adjusting rocker arm mechanism comprisinga plurality, moretparticularly apair; of interconnected rocker arms,I whereof each arm adjusts the other invalternatiomto continuously take out the lost motion or play as the latter develops, whether from wear of parts or variation in temperature with the consequent accompanying variation in operating length condition of push rods or valve stems. In this connection, the example of the invention illustrated herewith shows a pair of engine valves and their coacting rocker arms. An operating connection is provided between the two arms, whereby one rocker arm, when opening and closing its valve, automatically initiates the self adjusting function of the other rocker arm so the latter may automatically compensate and set itself to a no-clearance relationship with its particular valve parts while its valve is on its seat and thus condition itself for actuating its valve in relation to its seat.

inasmuch as rocker arms are usually provided in closely arranged pairs on each cylinder head of an engine to actuate the intake and exhaust valve of that cylinder, I transmit the working motion of one rocker arm to the other rocker arm when the latter is idle by which to initiate the resetting of the latter to its no-clearance position, but the invention comprehends deriving this working motion from any other convenient source of motion. The cam shaft affords this ready source of mechanical movement and so it is found practical and more direct in most engines to take this movement, required at a given rocker arm bearing, from the adjacent oscillating rocker arm itself, but the required motion may be derived from a special cam on the cam shaft or from other driven means. I mention these considerations inasmuch as l.' illustrate my invention with what is regarded as the simpler and hence better; form of construction. In this connection, it is a further object to produce in combination a self adjusting rocker arm pair for actuating the exhaust and intake valve pair in the same cylindei. The rocker arm pair (intake and exhaust) of any given cylinder, in a multi-cylinder engine, is conveniently adapted to my invention since one of the valves is always at rest on its seat and hence its rocker arm is idle so that the active valve and rocker arm are available to adjust the idle rocker arm.

With the foregoing objects and others in view, reference is now made to the accompanying drawings showing one of the concrete examples of the invention in which certain changes in structure and mode of operation may be resorted to without departing from the principle of the invention.

Figure 1 shows a side View of one of the compensating rocker arms of a coordinated exhaust and intake valve pair in one cylinder. Said arm is merely one of the parts in the chain of operating connections interposed between a conventional valve in a fragmentary portion of a cylinder head and the cam shaft of an engine. All parts are shown in rest position with the valve on its seat and the rocker arm has completed its cycle of adjustment and attained its normal no-clearance working position ready to open the poppet valve at the next revolution of the cam. This view may also be considered as partially developed on the section line l-l of Figure 2, except that the sectioned rocker arm of Figure 2 is assumed to be complete when laying out this side view of Figure 1, and also the section line 1-1 is assumed to pass thru the torque spring.

Figure 2 is a fragmentary plan view of the self adjusting rocker arm means or pair, and one of the rocker arms is shown in section, as cut along the section line 2 2 of Figure 1.

Figure 3 is a plan view of a torque spring means interconnected between the two dependently operating self adjusting rocker arm bearings. This spring urges first one bearing with its arm and then the other to the desired 11o-clearance operating position.

Figure 4 is a detailed View developed on the section 4 4 of Figure 3, showing one end or coil of the torque spring wrapped around the eccentric-type compensating bearing on which the rocker arm is carried, and the arrow shows the direction of the applied torque as exerted by the spring. This view also shows diametrically opposed clearance gaps or lost motion spaces left between the operating connections of the rocker arm pair by which to transmit only a necessarily slight self adjusting action from one rocker arm to the self adjusting bearing of the other arm and by which to accommodate the self adjusting apparatus to the differential variation between an exhaust and intake valve.

Figure 5 is a rear view of the uppermost portion of the mechanism in Figures 1 and 2 and shows the upper ends of the two push rods of the valve operating pair as connected with their respective rocker arms.

Figure 6 shows a cluster view of the separate parts placed in aligned order of assembly and constituting the few elements forming the operatively connected self adjusting rocker arm pair.

Figure '7 shows a side View of the rocker arm per se removed from its self adjusting bearing and showing a slot in the hub thereof disposed on the far side away from the engine cam shaft and by which the rocker arm hub is rendered contractible and expansible to lock or clamp its bearing therein which is a feature of this invention.

Figure 8 shows a longitudinal section thru the axis of one of the compensating bearings for one of the self adjusting rocker arms of the coordinated pair and having a motion transmitting sleeve to impart an easing movement to the adjacent bearing for the other rocker arm.

In the drawings, a typical valve in the head engine is indicated diagrammatically by reference to a fragmentary portion thereof, say a cylinder` head 3 having valve seats 4 and 5 defining intake and exhaust port openings leading to the cylinder of said engine 3. A pair of poppet valves of the usual kind include valve heads 6 and 7 with stems l ,i 'l

8 and 9, respectively. Valve closing springs 10 and 11 load the valve stems 8 and 9 in the usual way for returning and maintaining the valves 6 and 7 on their seats, following the opening operation thereof thru the agency of a rocker arm in- A dividual to each valve stem 8 and 9 which is actuated by a conventional cam also individual to each rocker arm.

A pair of rocker arms 14 and 15 are mounted on a common rocker arm shaft 16 supported by M- if.;

brackets 17 or other suitable'means above the cylinder block or engine head 3. A cap screw 18 for each bracket or post 17 securely fixes the rocker arm shaft 16 in the several brackets 17 along the top of the cylinder block 3 and also anchors said brackets to the cylinder block. This arrangement mounts the rocker arm shaft 16 against rotation and adapts it for the support of the self adjusting valve operating rocker arm means.

A pair of push rods 21 and 22 are actuated by a common cam shaft having a cam, including the usual lobe 23 and cam heel or drop 24, for each push rod and related valve 8 and 9, respectively, this mechanism operating in a-conventional manl ner and individual to eachlvalve 6 and 7, asy will` i be understood; An ordinary tappet or valve lifter 20 constitutes the cam. follower whichfridesthe i cam 23, 24 to actuate the rocker `arm and open its `in the cylinder 3. in mind that one valve of the pair is usually on valve when the canilobe traverses the follower 20. Each upper endof the pair of push rods'Zl and i 22 is operatively connected in any approvedmanner with the end portion or rear arms 25 and 26 of each rocker arm ifi and l5, as for example, by

`a ball and socket joint 27 including an adjusting screw and lock nut means 28 used for adjusting these operating. connections when assemblingV the mechanism. i

The ball joint 27 effectively transfers the thrust i of the cam lobe 23 and its respective pushrod to the oscillating rocker arm. The use of the screw adjustment` 23 `for accurately setting the balland socket joint 27 is optional `and merely a convenience and need be adjusted onlyoncepas for example,` when the engine isfirst assenibled,`

ing 11o-clearance working pressure or engagement throughout the general combination of all parts, including the push rod connection 27,'the rocker arm contact at the valve stems 8 and 9, and between the cam and followerZO.

.fis` will be understood by those conversant with the art, I have for convenience illustrated the valve pair 6 and 7, as an intake and exhaust, Hence the reader will bear its seat and thus its rocker arm is at rest and in a receptive state to automatically reset itself to the operating length condition `of all parts at the instant of adjustment when the other valve is off its seat and, thereforawhen `the rocker arm of the open valve is in motion and at work. The invention contemplates usinglthe motion of the` working or vactive rocker arm to `initiate the resetting or self adjusting action of the idle rocker arm which is not working. This `function.rapidly switches from one rocker arm `to the other, :back and forth, in constantly recurring function, while the engine is running, and the action is characterized by a minimum of relative movement betweenthe parts which avoids Wear and leads to long life. The two valves, intake and exhaust, with the related rocker arms 'of the saine cylinder 3, do vnot necessarily have to themselves be interconnected but that arrangement `is most convenient. Any two adjacent valves, where one is closed when the other is open, may be selected for this interconnected mode of operation. Y

The foregoing explanation outlines in a gen eral, way a typical form of internal combustion motor of a type employing a rocker arno,` as a part ofthe Valve operating connections or mechanism, for each valve and hence a rocker arm paiil of each cylinder. Based upon theforegoing example of'conventional engine valve means, a des :iption Will now be given of the features of construction and mode of` operation constitut- Ving this invention and by which all the advantages of self adjustment andlsustainedno-clearl shaft means 23.

ance operating relations are, effectively carried out.

The Vrst rocker arm 14 is `provided with a `hub 30 and similarly `the second rocker arm 15 is provided with its hub 31.

The two rocker arms may be the same in :form and the inside `bore thereof is `designed as a bearing surface within which `an eccentric undergoes perceptible rotative adjustment in both directions, up and down,

as indicated by the two arrows U and D in Figure 1, when the valve is on its seat and the rocker arm. isidle. The hub 30 is slotted longitudi- The rocker` arm` slots 32 and 33 ing to afford a degree of flexibility by which each hub bearing 30 `and 31 may contract and expand to a perceptible degree, thereby slightly Varying its insidediameter. The hub slots 32 and 33 are cut thru or otherwise formed longitudinally thru the hub portion above the rocker arm shaft 16, and hence the axis of the rocker arms is disposed generally between said slots and the engine cam Therefore, the upward thrust of the cam 23 and related push rod 21 against the arm 25l tends to close the slot 32 which contracts the inside `diameter of the hub bearing since the spring loaded valve sterne 3 and 9 initially resists pivotal action of the rocker arm as a whole, and the result is a denite closing and pinching or gripping tendency at each hub slot 32 and 33.

Each rocker arm hub `3() and 31 is mounted on the rock` shaft 16 thru the agency of an eccentric self adjusting bearing means having a novel mode of operation and which moves in both directions to compensate for contraction and expansion of theentire valve operating combination. There is provided an eccentric 35 for and within the rocker arm hub 3U and a similar eccentric 36 in the other rocker arrn hub 31. The inside axial bore 34 of each eccentric 35 and 36 constitutes its working bearing on which said eccentrics and the rocker arms carried thereby oscillate clockwise on the journal or shaft 16, as in Figure 1, to open their respective valves G and 7 in the usual way, and oscillate anticloeliwise `to aiord a valve closing motion by expansion of the springs 10 and 11. face 29 of each eccentric 35 and 36 also constitutes a bearing surface which undergoes a limited rotative adjusting movement in both directions, as at U and D in Figure 1, within each rocker arm hub 30 and 31 each time the valve is on its seat.

The outside diameter 29 of each eccentric 35 yand 36 is slightly less than the inside diameter in its rocker arm hub and is rotatably free to jjj.' `turn therein when said hub is at rest and re `laxed normally at its greatest diameter. However, the fineness and accuracy of the rotating bearing fit of each eccentric 35 and 36 within The outer their respective hubs 3() and 31 is such that the j',

eccentric is pinched, locked or clamped within the hub and moves rigidly as a unit therewith upon the slightest contraction of said hub as afforded by the slot pinching means 32 or 33 when `thecarn lobe 23 and push rod` 21 or 22 thrust eleupwardly against one end of the rocker arm 14 or 15.

The first eccentric 35 is made with an eXtension bearing sleeve or reach hub 37, and the second eccentric 36 is similarly made with a like extension sleeve 3S. The two sleeve means 37 and 33 reach or bridge the space between the two dependently self adjusting rocker arms 14 and 15 and coact with each other by imparting an oscillating movement back and forth, one to the other. The eccentrics with their integral sleeve extension means 37 and 38 have a common axis for their internal bores 34 and for bearing fit rotatable upon the stationary rocker arm shaft 16, particularly in constructions where the rocker arms 14 and 15 are somewhat distant from each other.

rThe sleeve or bearing extension 37 is notched or stepped back from its end by cutting away a portion 'thereof circumferentially between the eccentric bearing body 35 and said outer end. The cutaway portion in effect leaves a notched end having oppositely disposed companion shoulder edges or jaws 39 and 40 which may be parallel t the shaft 15 and turn or rock circumferentially thereon. 1n the saine way the self adjusting bearing 36 has the outer end of its sleeve 38 designed to form a pair of opposit-ely spaced shoulder means 41 and 42. The two notched sleeves 37 and 38 are loosely engaged or clutched together on the shaft 16 by which a portion of the rotative movement of each sleeve is communicated back and forth to each other in constantly recurring function.

The integral shoulder pair 39 and 40 measure slightly less than a semi-circle, ordinarily a few thousandths of an inch, than one hundred eighty degrees; and the same is true of the spaced integral shoulders 41 and 42. Hence the jaw 39, 41 and companion jaw 40, 42 may only close one at a time or coact in alternation, one after the other. As the sleeve jaw 39, 41 close-s, the 0pposite jaw 4D, 42 opens and vice versa. One sleeve, say 37, therefore, has a pronounced motion rela-- tively to the other, 38, before engaging and actuating the latter, and reversely as to sleeve 38 the sanne is true in relation to the former.

The separate shoulders 40 and 42 coact to transmit motion from the eccentric bearing 35 to 36 when rocker arm 14 tilts clockwise (Figures 1 and 4) to actuate its valve 6; and similarly the other set of shoulders 39 and 41 coact by which the eccentric reversely acts on S to oscillate the latter when the other rocker arm 15 tilts to open its valve 7. Both actions kick up, as at U in Figure l, on the compensating bearings and 36 to bodily lift the rocker arms 14 and 15 to ease and free there of and from working pressure or mechanical. cramps, so to speak., by taking out the lio-clearance engagement at the ends of the valve stems 8 and 9 to insure that each valve 6 and 7 positively seats.

lf2/hen the two eccentrico 3.5 and 36 are assembled on the shaft 16, there is left the predetermined clearance or lost motion space between the adjacent coasting shoulders forming each operating jaw 39, 41 and 40, 42, as heretofore mentioned. This clearance permits of a limited oscillation of either eccentric 35 or 36 in relation to the other before one eccentric actually coacts with and kicks up or trips the other to initiate the automatic upward adjustment of the latter. In this way, the active or working eccentric and its rocker arm has its valve well open before communicating its bodily lifting adjustment action, as

at the reference U, to the other eccentric and its arm, and thus is avoided undue or over adjustment or lifting of the idle rocker arm. A limited and indeed only a perceptible lifting or easing up and freeing movement of each eccentric is required, to eliminate the mechanical pressure or cramps, so to speak, at 27 and at all other points of engagement beginning at the cam and extending to the valve seat, and by which to insure perfect and positive closing of the valves S and 'l by their springs 10 and l1.

In assembling the mechanism, the eccentric 35 is operatively confined within its cooperating rocker arm hub 30 and likewise for the eccentric 36 and its hub 31. The two rocker arms 14 and 15 are now spaced apart and set to engage the tail or outer end of their respective valve stems 8 and 9. The two reach sleeves 3'? and 38 are now disposed in overlapping operative engagement, and the shoulders 39 and 40 of the eccentric 35 are clutched and interconnected in working relation with the shoulders 41 and 42 of the other eccentric 36, as heretofore explained. It is now apparent that the few thousandths of an inch narrow clearance or lost motion space between the adjacent shoulders 39 and 41 and the diametrically opposite shoulders and 42 permit a limited amount of relative motion between the two rocker arms 14 and 15, the same as heretofore explained for the self adjusting bearings 35 and 35. The two-way adjusting eccentric bearings 35 and 35, and hence the rocker arms 14 and 15, are now operatively connected so that the latter portion of the travel of one arm 14 lifts the other perceptibly and vice versa. In view of the slight lost motion or rocking play relatively between the two rocker arms 14 and 15, it follows that each arm attains a rocking start, initially, before kicking up or lifting the other. To emphasize this feature, note again that this space of a few thousandths of an inch is preferably left so that only a portion of the valve lifting oscillation of one rocker arm, say 14, is imparted to the con pensating bearing 36 of the other rocker arm 15 when the latter is idle.

The coacting adjacent shoulders 39 and 4l constitute in effect one operating jaw while the other adjacent shoulders 40 and 42 provide an oppositelydisposed operating jaw. By varying the jaw space between these coacting adjacent V shoulders, it follows that the jaw 39, 41 or 4G, 42 open and close sooner or later, as the case may be, in relation to the pivotal action of the two rocker arms 14 and 15. It is found in some engines that the full throw normally required return to a readjusted and more precisely coind pensated lio-clearance relation to the then changed operating length condition of all the parts in the combination. Consequently, the jaws 39, 41 and 40, 42 are made with the lost motion space so that the shoulder 40 does not pick up and trip its companion shoulder 42 until the rocker arm 14 has spent part of its valve opening movement. Thus is minimized undue movement of the compensating parts in the rocker arm pair.

It is important to note that each compensating element 35 and 36 is mounted on the rocker arm shaft 16 with the major axis of the eccentric disposed horizontally or substantially perpendicular to the axis of the push rods and valve Cil position lshould the push rod or valve stem haveY elongated.' Likewise `the reverse is true when ir the` eccentric 35 is reversely urged rotatively downward (as atD) or counter clockwise, by means to be explainedbe'cause the rocker arm 14. is then set snugly downwardly against the top end of the valve stern 8 and the ball joint 27" lfand thus tightenedup to a no-clearance relation. Both rotative adjustments, 'at U and DFigure l, start and` nishwhile the valveis on its seat= and repeat this freeing and resetting action `each 'time said valve seats# 201 A torque `spring has its center 44 anchored in any suitable manner to a stationary support such as an adjustable screw 45 `,which is adapted to screw up or down in the engine or cylinder head 3 to varythe tension exerted by said* spring. A

25fl=fpost Riina-y` beused if desired to support a clip or hook 47'=to retain the spring in place while allowing its free ends or `coils 48and 50 to independently exert a downward torque `in the direction "of the arrow D on both eccentric bearing means S5'and-36 for the automatic tightening up compensating cycle of self adjustment for each rocker arm 14 and `15. The spring 44 has one end 48 coiled about the sleeve .'37 and said end is insertedin a springsocket or hole 49made within 3i? n the fend of the thickbody portion of the eccentric 35. rIihe othery end 50 of the spring is coiled about the extension jaw 38' and is inserted' in a hole'5l similarly made in the other eccentric `36.

The two coils 48 and'50 f of the torquespring fill" disposed axially of the bearings 35 and 36 are suitably tensicned to continuously exerta downwardly unwinding or' rotative vadjusting force by turning both eccentric bearings in an anti-clockwise direction, as viewed in Figure 1. Also the properly spaced' position: The adjustingffunction n of both spring enlds`4-3and 50 is to independently" urgedou'fnwardly on thetwo eccentricsA 35"'and 36,rst one "then -the otherin `the `'direction f of th`e"arrow`D,thus urging bodil'ydowriwardly onl both 'rocker"'arms"14 and l5 to maintairiboth` ends thereof" in no-'clearance relation with their respective valvestem and push rod.- Thisfcon-` stantly recurring V`downwardly I adjusting action, as at D, of the springV takes-place ofcourse immediately afterxthe lcompletion ofi theup -turn of4 the eccentric, aswindicated ati/U.P

inv the operation of thevalvemechanism of an internal combustion engine,- it is well understood 'i how variationintemperaturel and also wearand impact of `parts is accompanied by variation in lengthfof parts. For example, the push rods, the valve stems andthe cylinders of anengine expand perceptibly when `the engine warms up to running condition.` Likewise"theseparts contract or shorten. because of a drop in temperature or dueto `the i'act that wear occurs at the valve or other engaging surfaces-L The compensating rocker arm means of this inventionA accommodates" all variations iin; operating length lrelation with other parts.

wear or shortening of partsfand-by giving, yielding, or letting out `so to spealnwhen' the push rod,

i valve stem and otherparts expand or grow longer.

In other words, the eccentricbearing means35 and 361.1 cooperate with their respective `rocker arms 14 and l-by moving said arms up-and down perceptibly to maintain aneasy, yet positive noclearance operating relation between the engaging surfaces of the rocker arm andvalve stem, as

conditions by automatically taking up for all well as the ball-and socket joint 27, likewise with the cani and valve tappet, and such other parts as are employed in the valve operating mechanisml or connections in generali To describeithe complete opera-tion of the invention in cneconnected cycle, it is now assumed that the engine is running andthe cam'lobe 23 is idling along the tappet 20;A Hence the iirst rocker arin'14 .is standing still and its bearing 35 is assumed to have completed its` two stage adjust-A ment `comprising the freeing and resetting operationss At this stage the `other valve 7 is at rest i on'its seat 5 and hence its rocker arm 15 is `like- `wise at rest and the eccentric bearing 36 of the latter has just been unclamped in its `hub 31 due to the return of said rocker arm 15 to'rest position with the heel 24I of the cam'idling-over the tappet'20, and the rocker arm 15 may be cramped or otherwise slightly oil its desired `no-clearance i New as thecarn lobe 23 approaches the iirst push rod 21 to thrust upwardly on the first rocker arm 14, the initial lifting impulse is of course resisted by the valve closing spring 10, `the result of which is to tension the f rocker arm end 25 upwardly which draws and tensions the lower portion of thev rocker arm hub 30, `thereby contractingsaid hubs() and gripping or clamping therein the adjustedbearing since f the slot 32 promotes thishub contraction. Thus the previously adjusted eccentric bearing 35 is now locked within Athe huby 30, is rigid in and turns 'as a with/the rocker arm` 14, and the latter `therefore oscillates clockwise about the axis A of the shaft 16,'not on or relatively to its self `adjusted member 35 while opening its valve 6. In `tact, the rocker arm 14 and its eccentric 35 are now definitely locked together and act as a unit to tilt both clockwise and counter clockwise throughout the entire period the camv lobe 23 is traversing and-reciprocatingIthetappet 20` and 1 In other words, as long as .push rod means 21. thewalve is oir its seat, the hub,` 30 grips and locks'the eccentric 35 therein because both ends oi the rockerarm lare tensioned upwardly and the hub `slot 32 isunder this combined closing torce. The rocker arm hubs automatically lock their respective bearingstherein to oscillate` said bearings `with said hubs against the yielding-fresistanceof the torquespring means 44 tending to hold said bearings in downwardly limited position.

The foregoing clockwise tilting action of the i rocker' arm 14 to open itsvalve 6 also acts posi- -tively (thru the jaw 49,- 42) to kick the `freeler looseV eccentric bearing 36 of the other rocker arm 15 upwardlyv in the direction` of the'iarrow U in Figure 1 and against the torque of the spring end 50 always exerted downwardly on said bearing 36, as indicated by the 'other arrow D. Hence the torque spring endy 50 is wound up or slightly tensioned additionally to` its inherent torque by each working stroke valve opening action of the other rocker arm 14 when the latter is actuated by its cam lobe'.

Now it is seen that the idle rocker armv 15 has been perceptiblyand forcibly lifted or eased away from its push rod 22 and valve stem 9 at each working operation of the other arm 14. As soon as the first working arm 14 and its locked bearing 35 have completed their rocking movement and tilt back to idle position, it follows that the shoulder 40 of the working eccentric 35 draws away from the shoulder 42 of the lifted eccentric 35, whereupon the torque spring end 50 is perfectly free to return the lifted idle eccentric 36 and its rocker arm 15 back downwardly to reset both of its ends snugly up against the push rod 22 and valve stem 9, which action occurs while the valve 7 is on its seat 5 and the cam heel is traversingr its tappet. The torque spring coil 50 now definitely completes this resetting function before the cam lobe 23 begins to lift the push rod 22. Any variation in length of the push rod 22 or valve stem 9, which would prevent the valve '7 from seating or which would leave clearance in any moving part between cam and valve seat, is instantly compensated for between the time the eccentric 36 is urged up as at U by the positive mechanical action of the jaw means and returned downwardly to reset it as at D by the resilient action of the torque spring.

There now exists no possible looseness between the idle rocker arm l5 and its push rod 22 or valve stem 9 because the force of the torque spring 44, 50 is sufficient to enforce a rin seating contact in the ball joint 27 and also between the rocker arm and top end of the valve stem. Of course the torque spring is not sufliciently strong to unduly bear the cam follower against the cam heel 23 or force down on the valve springs l0 or ll. The force of each torque spring coil 48 or 50 is just sufficient to instantly set their respective rocker arms snugly down with no-clearance engagement against the respective push rods and valve stems. Also each coiled section of the torque spring 44 easily yields and tends to coil or wind up a little more under the superior mechanically rotated force of the other rocker arm, but the spring is initially installed with applied unwinding torque so as to possess sufficient strength to maintain the rocker arm bodily downwardly at all times except when positively lifted by the sleeve jaw of the opposite rocker arm.

It is now understood that the second rocker arm 15, which was first eased and secondly reset while idle and while its cam heel was traversing the tappet, is now ready to be acted upon by the engine driven lobe of the cam. As said cam lobe begins to ride the tappet and push rod 22, the hub 31 of the rocker arm 15 first grips the automatically compensated and reset eccentric bearing 36 and freezes or pinches it so to speak in said hub 31, as hereinbefore explained for the first hub and its self adjusted bearing 35. The rocker arm l5 is now instantly conditioned to roel: about its axis 16 because of the pinch slot 33, and there is no possibility of said rocker arm 15 turning relatively on the face l29 of the eccentric bearing 36. Hence the rocker arm 15 now functions in the usual way to open its valve under the throw or thrust of the cam lobe, but characterized of course by the fact that there is no operating clearance between any parts. Quiet operation, therefore, follows and all impact is eliminated due to a complete absence of all operating clearance heretofore ordinarily left in the rocker arms of engines to insure the seating of the valves.

As said second rocker arm l5 tilts on the rock. shaft 16 it follows that its bearing 36 anchored therein by the pinch slot 33 now acts reversely back thru its shoulder 42 to 'pick up the idle shoulder 40, whereupon this means 40, 42 in jaw closing fashion kicks up the first bearing 35 and its rocker arm 14. Thus I have traced the oscillating action of the twin parts constituting this self adjusting rocker arm pair and the reader will understand that the mode of operation continues in constantly recurring fashion, back and forth, more rapidly than the eye can follow, with the completion of the three stages or cycles of adjustment, ease or freeing, resetting to snug 11o-clearance, and finally relooking of the bearing in the rocker arm so as to positively avoid adjustment during the valve opening and closing period.

It is important to note that the locking or clamping of the adjusted bearing is effected while the torque spring is holding down on said bearing. Therefore each rocker arm starts its movement with its bearing snugly set to negative all looseness thruout all parts of the mechanism. As the rocker arm continues its oscillating movement and for the duration thereof, the hub pinching slot is responsive to the pressure generated at the cam and at the valve spring. The hub, therefore, positively clamps its bearing so there is absolutely no possibility of the bearing slipping or changing its position in the least way during the rocker arm working period.

The pinch slot at 32 or 33 illustrates an example of bearing clamp means by which said cornpensating element 35 or 36 is restrained from slipping motion or displacement during the period the rocker arm is under working stress to actuate its valve. This construction affords a frictional gripping and non-slipping engagement throughout the entire circumference of both the hub and bearing and thus positively insures against loss of the no-clearance adjustment which is automatically and so effectively set up throughout all parts of the mechanism just prior to the operating cycle when said rocker arm goes under working stress. 1t will be appreciated that this pinch hub construction 30, 32 is simple and inexpensive to manufacture, possesses the mechanical leverage advantages over the bearing, as explained, and is preferred in many instances over other forms considered. To grip only a portion of the circumferential s irface of the eccentric bearing 35 or 36 does not afford the full measure of frictional holding effort to restrain the bearing against displacement, as accomplished in the concrete ein-- bodirnent of the invention as here presented. Also it is noted that the hub 30 or 31 is, inherently, its own releasing means, to instantly relax and free its bearing 35 or 36 from its rigidly locked state when the ends of the rocker arm are not under thrust. It is contemplated, however, that other forms of locking and releasable restraining means for the control of the bearing within the hub may be used without departing from the spirit and principle of the invention.

Reference is again made to the function of the self adjusting control, or the loosening cycle thereof, exercised by the motion transmitting jaw means 39, 41 and 40, 42. Should the valve stem 8, for example, be regarded as the exhaust valve, it follows that its expansion may be more rapid and ultimately .come two or three thousandths of an inch longer than its companion valve, the intake 7, 9. That being true, this explains that the shoulder 40 does not reach to interfere with the normal adjusting action of the adjacent shoulder 42. The considerable space initially provided at each jaw 39, 41 and 40, 42 adequately accommodates all possible differen- `engine warms up,`

, haust valve. .Zl and 42, or reversely,

`operating refinements oi my Zero or where the cylinders are in transmitting the desired easing vor freeing-up represented at 35, 37er 36, 38.

tial ranges in rate of valve stern` variation (con-1 traction or elongation) which may' occur. The` intake valve stem elongation mayflag asthe i. e., the intake valve `stein f ordinarily does notget as hot as theexhaustf valve stem and lconsequently itmay oe slower in growth and never reach the extreme change as'characterizes the moreY severely-@treated exe The jaw space between shoulders between 39 and 41, takes care of this variable factor as-regards Yth'eslight` difference in rate of contraction and expansion of the parts. One motion transmitting -jefwinay` Yultimately attain a `closer working relation 'thanil" "the other as the engine warms up. These provisions, therefore, effectivelyl accommodate the slight variation in operating characteristics,as between an exhaust and intake valve,where they are taken as a pair and made to conform tothe rio-clearance rocker arm means.

It will be apparent that the intermittentlyoperated valve pair and its rocker arm` groupmay or `may not he in the saine engine cylinder, butline, there is ordinarilyi provided a common axis 16 or rock shaft for all rocker arms and the construction and adaptation i of my invention is simplified inasmuch as l am,` able to employ the same axis 16 as an aid in motion from one rocher arm to the compensation* means ot the other, and vice versa. `There are less common engine constructions not having one and the same journal or retainingfaxisfas *at 16, for the rocker arm pair, as 'for example,

in cases where the valves are disposed at anI angle to each other in the cylinder, and falso where the oscillating axis of each rocker arm hub is angularly related to each other. In such cases, the necessary easing motion for slightly tilting and freeing the respective bearings, is suitably transmitted directly froml the" cam shaft or other rven means, or may be transmitted from one rocher arm to the other over the angu-v l'lar path therebetween.

I have produced improvements in the rocher arm per se which includes the hub 30 or 3l, enlarged `over conventional'practice if 1ieed-\he',-- together with the pinch ` slot 32 or 33 and made of hard metal or otherwise possesses elastic l or resilient characteristics by which said hubfreturns to its normal maximum diameter whenre-"r lieved of stress; and alsod have produced "the new bearing and jawed sleeve means `per se Soalso my in vention resides in the combination of said new rocker arm and the bearing element operative therein. Further, my invention comprehends the interrelated valve `and rocker armpair, Ain come bination. Likewise l have produced, asia new article of manufacture for this particular purpose, the novel one-piecespring means having the tivo torque coils i8 and 50 which independ-` ently react from a common stationary center to reverse or return the compensating bearingsito down or rid-clearance position, and tl'iis-con struction, in many instances,y possesses certain advantages over two separate torque springs;

As a whole, the operating parts of my inven` tion are small and coinpactly arrangedin the" space available on standard engineaemploying' rocker arms for vention .iills a need felt for an economical `valve control which is silent, self adjusting, and eliminates wear and deterioration of the mechanism.`

spring connected with actuating the valves. 'rhein-*- longitudinal slot therein to What `is claimed is:

1.1In combination, a valve having a seat and a spring lto seat the valve, a cam shaft and oscillating member to actuate the valve in relationfto its seat, compensating bearing means onrwhioh'-theosoillating member is operatively mounted; mechanically' driven means cooperating witlrthe compensating bearing means to positively shift same in one direction after the Ivalve has reached its seat to free the entire com bination-'of cramping action whereby said valve is positivelyseated by its spring, resilient means operableindependently of the mechanically driven means to urge the compensating bearing means in the other direction while the v ive is still on its seat to snugly set up the cam s `t and oscillating member into `a 11o-clearance operating engagement, and locking means to positively fix `the compensating bearing means and oscillating member rigidly together to operate as a unit while the valve is still on'its seat.

2. Valve' operatingmechanism for engines and i the `like comprising a rocker arm having a hear ing lhuhl adapted-to oscillate about a retaining axis, a compensating bearing mounted for free movement within Vthe huh and on the rem leasable clamping i'neanscooperating with the rocker arm hun and the bearing to positively lool: said bearing `when said rocher is in motion so they move together as a unit and also releasable when the rocker arm is at rest to aitord freedom; of= movement of the bearing within the roclrerV arm` at" that time, mechanically driven means connected with the bearing to turn it in one direction when' the clamping means is released, and resilient means to reverse the bearing and -turn it in the other direction while the rocker arm is still at rest.

3. Valve operatingmechanisin for engines and compensating bearingrotatably confined the hub, releasable clamping means cooperating with the rocker armhub and the bearing therein andy ed with tl'iebearing to turn the latter one rection` when the clamping means aforesaid is releasedgand a toroue spring having one end connectedtothebearing and the other end held stationaryftoreversethe bearing and turn it in the other-direction while the rocker arm is still at 1.

4. Valve operating mechanism comprising a rocker arm adapted to oscillate on a roclr shaft and to actuate a valve in relation to its a -lnibcf greater diameter than shaft and proM i 4vided withmeans to ailord contraction and expansionfot said hub when. the latter is in mo-` tion; an` eccentric conned in the huo bored to forma bearing on the `roclf; eccentric having its maior axis disposed perpendicular to the valve, an actuating device to adjust the `eccentric* upwardly away from the valve when the rocker-alanis not in motion, and a toroue the eccentric to adjust it is not in downwardly also 4when the rocker mot-ion.` i i 5. A Aroclrer arrncfor actuating spring loaded valves and having a hearing hub provided with a afford huh controction, an eccentric in the bearinghub free to rotate 1 the like comprising a rocker arm having a hub, I

together as a unit and re therein but subject to a clamping action to lock it for oscillation with the rocher arm when the latter contracts, means to adjust the eccentric in the hub and thereby reset the rocker arm to a 11o-clearance engagement with the valve.

6. A rocker arm for actuating s ring loaded valves comprising a. bearing hub formed in said rocker arm, said hub being cut thru to its bearing to render the latter variable in diameter, an eccentric rotatably free within the bearing hub when the latter .is at its greater diameter and gripped therein against rotation when the hub diameter reduces, and means to adjustably turn the eccentric first in one direction and then the other to adjust the rocker arm. to a no-clearance relation. with the mechanis 7. A rocker arm for actuating a spring loaded valve, comprising a bearing hub provided with a longitudinal slot therein formed above its axis of oscillation and on the side of said axis opposite that of the valve, an eccentric in the bearing hub free to rotate therein but subject to a clamping action to lock it for oscillation with the rocker arm when the latter actua-tes the spring loaded valve causing said hub to contract, and means to adjustably turn the eccentric in the bearing hub and thereby set the rocker arm to a 11o-clearance operating relation with the valve.

8. A rocker arm for actuating a spring loaded valve and adapted to be actuated from a cam shaft, comprising a bea-ring hub provided with a longitudinal slot therein formed above its axis of oscillation and on the side of said axis opposite that oi' the valve and the cam shaft, an eccentric in the bearing hub free to rotate therein but subject to a clamping action to grip it for oscillation with the rocker arm when the latter responds to the cam shaft to actuate the spring loaded valve thereby causing said hub to contract, and means driven from the cam shaft to adjustably turn the eccentric upwardly away from the valve and cam shaft to loosen up the rocker arm in relation to said valve and cam shaft, and a torque spring coiled about the axis of the eccentric and attached to said eccentric for adjustably turning it downwardly to reset the rocker arm to a no-clearance working relation with the valve and cani shaft.

9. A rocker arm for actuating a spring loaded valve, comprising a bearing hub made of elastic metal and provided with a longitudinal slit therein formed above its axis or oscillation and on the side of said axis opposite that of the valve, an eccentric in the slit bearing hub and free to rotate therein but subject to a clamping action to lock it for oscillation with the rocker arm when the latter actuates the spring loaded valve causing said hub to elastically contract, and means to adjustably turn the eccentric in the bearing hub and thereby compensate the rocker arm to a noclearance relation with the valve.

10. A rocker arm for actuating a spring loaded valve in relation to its seat, comprising a bearing hub formed in said rocker arm, said hub being formed of elastic or resilient material and out thru to its bearing to render the latter variable in diameter, an eccentric rotatably free within the elastically variable bearing hub when the latter is at its greater diameter and adapted to be gripped therein against rotation when the hub contracts and reduces its diameter, and independently operable means to adjustably turn the eccentric in both directions in the hub when the latter is expanded to adjust the rocker arm to a no-clearance relation with the valve.

ll. A rocker arm and valve operating mechanism, comprising a rocker means adapted to oscillate on a rock shaft and to actuate a valve in relation to its seat, a hub of greater diameter than the rock shaft and having arms integral therewith, said hub being cut thru to form a pinch slot between the arms above the valve, an eccentric conned in the slotted hub and bored to form a bearing on the rock shaft, said eccentric having its major axis disposed perpendicular to the valve, an actuating device to adjust the eccentric upwardly away from the valve when the rocker is not in motion, and a torque spring connectfed with the eccentric to adjust it downwardly when the rocker arm is not in motion.

l2. Valve operating mechanism comprising in combination, a pair of rocker arms adapted to oscillate about the same axis on a common shaft, an eccentric bearing on which each rocker arm is mounted, means to lock each eccentric bearing to its rocker arm only when the latter is in motion, sleeve means oscillated on the aforesaid axis and shaft by the rocker arm and engaging one eccentric bearing to turn it in one direction relatively within its rocker arm when the other bearing is locked in and oscillating with its rocker arm, and torque spring means to actuate the bearing in the other direction.

13. Valve operating mechanism comprising in combination, a pair of rocker arms adapted to oscillate about a common axis, an eccentric bearing on the same axis and on which each rocker arm is mounted, means effected by movement of the rocker arm to lock the eccentric bearing therein, sleeve means interconnected between each eccentric bearing and oscillated on said common axis by the rocker arm to turn one eccentric bearing in one direction within its rocker arm when the other eccentric bearing is locked in and oscillating with its rocker arm, and torque spring means attached to each bearing to actuate same in the other direction.

i4. Valve operating mechanism comprising in combination, a pair of rocker arms adapted to oscillate on a common rock shaft, an eccentric bearing on which each rocker arm is mounted, means to lock each bearing in its rocker arm when the latter is in motion, sleeve means oscillated on the same rock shaft by the rocker arm and serving to turn one eccentric bearing in one direction within its rocker arm when the other eccentric bearing is locked in and oscillating with its rocker arm, torque spring means wound axially around the sleeve means between the two rocker arms and secured to each eccentric bearing to adjust said bearing in the other direction, and means anchoring the center of said spring in stationary position.

l5. Valve operating mechanism comprising in combination, a pair of rocker arms mounted in spaced relation, an eccentric bearing movably free in each rocker a sleeve extension integral with a bearing and reaching toward the other bearing, an operating connection between the sleeve extension and said other which the movement of one rocker arm actuates the other bearing in one direction, releasable locking means to grip one bearing in its hub when the other bearing is free in its hub, and spring means attached to each bearing to actuate it in the other direction after the locking means has released.

16. Valve operating mechanism comprising in combination, a pair of rocker arms mounted in spaced relation, an eccentric bearing movably j bearing by free in each rocker arm; a sleeve carried by each bearing, reaching toward the other, and having coacting shoulder means by which one sleeve engages the other; clamping means to grip one bearing in its rocker arm when the other bearing is free in the other rocker arm, and a torque spring means for each bearing coiled around each sleeve and connected to said bearing.

17. Valve operating mechanism as deiined in claim l5 but provided with lost motion means at the operation connection between the sleeve extension and said other bearing by which one rocker arm moves `part Way before actuating the bearing in the other rocker arm.

18. Valve operating mechanism as covered in claim `16, characterized by a lost motion space being provided between the coacting shoulder means, whereby a part only of the motion of one rocker arm is transmitted to the eccentric bearing of the other rocker arm.

19. A rocker arm pair, in combination, for operating valves, and mounted in spaced relation, an eccentric bearing and releasable locking means to alternately fix and release same within each rocker arm, a motion transmitting device interconnected between the two spaced eccentric bearings so that they both turn together in one direction, and spring means tensioned against said eccentric bearings to urge them in the other direction.

20. A rocker arm pair, in combination, for operating valves, and mounted in spaced relation, an eccentric bearing and releasable locking means to alternately x and release same within each rocker arm, a motion transmitting device interconnected between the two spaced eccentric bearings so that they both turn together in one direction, means affording lost motion in the device whereby one bearing initially starts and turns part way before picking up the other bearing, and spring means tensioned against said eccentric bearings to urge them in the other direction.

21. Valve operating means, comprising two rocker arms, in combination, to actuate valves in respect to their seats, a compensating bearing for each rocker arm, each bearing provided with a hole in its end directed toward the other bearing, two coil springs interposed axially between the` bearings and resiliently expanding against the bearings to hold them and the rocker arms in spaced relation, the two springs being integrally joined at their adjacent ends and anchorage means thereat to hold this joined spring in stationary position, said two springs being coiled in the same direction axially in respect to the bearings and having their outer free ends inserted in the holeaforesaid of each bearing and being initially tensioned to exert Van adjustable turning force on each bearing in one and the same direction, positively driven means operatively connected with the bearings to turn them in the other and same direction, and locking means to restrain the bearings from movement in respect to the rocker arms during the actuating period of the latter but releasable when the rocker arms are at rest whereby the springs and positively driven means may operate the bearings aforesaid,

22. An assembly for valve operating mechanism, comprising a rocker arm having a bearing receiving hub between its arms, said hub being split lengthwise between its arms to render the hub contractible, an eccentric bearing rotatably confined within the hub and the major axis of said eccentric being disposed substantially parallel to the arms, and a coil torque spring attached to the eccentric bearing.

23. An assembly for valve operating mechanism, comprising a rocker arm having a. bearing receiving hub between its arms, said hub being split lengthwise between its arms to render the hub contractible, an eccentric bearing rotatably coni-ined within the hub and the major axis of said eccentric being disposed substantially parallel to the arms, said eccentric bearing being bored to form an internal bearing adapted to receive a rock shaft, a sleeve extension carried by the veccentric bearing and projecting axially from the bore, and a coil torque spring attached to the eccentric bearing.

24. An assembly for valve operating mechanism, comprising a rocker arm having a hub intermediate its ends, said hub being split between its arms at the upper portion of said hub, an eccentric mounted in the hub with the major axis of said eccentric disposed substantially perpendicular to the plane of the split and parallel to the arms, said eccentric being bored to form a bearing adapted to receive a shaft, a sleeve projecting from the eccentric axially of its bore and having engaging means to operatively connect with mechanically driven means, and a torque spring coil wrapped about the sleeve and connected with the eccentric.

25. An assembly for valve operating mechanism, comprising a pair of spaced eccentrics each of which includes a sleeve projecting toward the other and abutting substantially centrally fof the eccentrics, each of said abutting sleeve ends made with a clutch means approximately the counterpart of the other and engaged with lost motion by which each eccentric transmits motion to the other in reversely recurring operations, a two-part torque spring having one end coiled around one sleeve and attached to one eccentric and its other end similarly coiled around the other sleeve and attached to the other eccentric, and a rocker arm having a split hub mounted on each eccentric.

26. As an article of manufacture for use in connection with valve operating mechanism, a rocker arm having a bearing receiving hub intermediate its ends, an eccentric snugly iitting in the bearing receiving hub, and said hub being split thru ROBERT C. RUSSELL.

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