US2982273A

US2982273A - Double rocker arm assembly

Info

Publication number: US2982273A
Application number: US850187A
Authority: US
Inventors: Paul F Bergmann
Original assignee: Johnson Products Inc
Current assignee: Johnson Products Inc
Priority date: 1959-11-02
Filing date: 1959-11-02
Publication date: 1961-05-02
Anticipated expiration: 1978-05-02

Description

May 2, 1961 P. F. BERGMANN 2,982,273

DOUBLE ROCKER ARM ASSEMBLY Filed Nov. 2. 1959 rl/l'l//ll INVENTOR PAUL E E/QGMA/V/V Fm; 3 y 2@ BY im uw 2 7 ATTORNEYS United States Patent() DOUBLE ROCKER ARM ASSEMBLY /Paul F. Bergmann, North Muskegon, Mich., assignor to .L-pianeIn-inofrigm l Fig. 4is,.aperspective-view of allrocker.-

Johnson Products Inc. Muske on Mich. a cor oravtion of Michigan g p Filed Nev. z, 1959, ser. No. 850,187

` 11 claims. (c1. 123;-90)

'This invention pertains to al rocker arm assembly and more particularly to a double rocker armassembly.

Previously rocker arms have been positioned with respect to the push rods and valve stems vof an engine by securing them to a rockerv arm shaft, or by securing them individually on a-fastener. To secure the rocker arm to a rocker arm shaft it has been necessary to provide the rocker arm with some type of aperture `so that the rocker arm can b e` positioned Von the rocker arm shaft androtate thereabout. Such apertures inthe rocker arrntend to weaken the rocker arni because it is constructedfof the minimum amount of material necessary for economy purposes, and the amountof material between the aperture andthe edge of the rocker armis notralways suflicient for proper strength. Therefore, `frequently cracks form between the aperture and the edge of the material andserious trouble results. .The same problem is present Where the rocker arm is secured in position by means of Va single fastener.

thereof and the same type of cracking and breakagel beshows la portion of the engine block 11. The engine block 11 is seen to have a surface 26 which forms a foundation for the base support 12.- The base support 12 is a rectangularly shaped member and has an aperture therein adapted to receive a bolt Afor securing the rocker arm assembly to the engine block.

The bottom of `the base support member is machined to correspond with the surface 26 of the engine block 11. The top of the base support member 12 has a U- shaped groove lmachined therein across the width thereof to provide a saddle for a rocker fulcrum nowv to be described.

The rocker f ulcrurn-13 is Vof a U-s'hap'ed design as best shown in Fig. 1. The fulcrum has an outside bearing surface 4,1, dimensioned so as to form abearing fit with l the U-shaped groove in the base support member 12, and

in the assembled position fits snugly in the saddle formed by the groove in the basesupport member 12. The

rocker fulcrum 13 is of a length so that it extends beyond both sides ofl the base support 12 to form a fulcrum for the rocker arms. This feature will be explained more fully hereinafter. The fulcrum 13 has an aperture disposed centrally therein to correspond with the aperture inthe base support 12. p

A clamping block 14 is ldesigned to tit within the U- shaped rocker fulcrum 113 andf clamp the Ushaped rocker fulcrum member1`3`to the base support 12. The bottom of the clamp block 14 is` machined toc'orrespond in This arrangement of the rocker arm necessitates an aperture through the central portion tween the edge of the rocker arm and the aperture will result. It is thereforean object of this invention to-dis- .close a rocker arm that `can be secured in the' proper position without thenecessity of formingan aperture therein. L v l It is another object of this invention to disclose a rocker arm thatk is secured in position without the use of a rocker arm shaft vor a fastener 'extending therethrough.

Still another object of this invention is to disclosed a double rocker arm `assembly in which=the v rocker arms are disposed in pairs.` 3 Y A further object of-ithsinvention is to disclosea rocker arm that is suspended and'secured in position by :means ofaspringclip. v

Another object of this invention is to disclose a rocker arm that is easily lubricated., Y l t Still anotherobject of this invention is to'fdisclose a rocker A tions.V y,

.Anotherobject of this-.invention is to disclose a rocker arm. that can bestampedorpressed from steel.

These and otherobjects and yadvantages, of the practice v"of thisinvention will be more apparent in the iliustration vand!` description ofthe working embodiment ofl the in. v .ventiomas'hereinafteryset ifo'rtl'i. v

In the drawings;

Fig. 1" shows aside elevational rocker'arm assembly. t

t Fig. 2 shows a top planview ofFigLl.

rFig. V3 showsa crosssectional view taken arm assembly lthat willreduce 'harmonievibradesign and dimension to the inside ofthe U-shaped rocker fulcrurn 13 as best shown in Fig. '1. The clamping block 14 is approximately the ksame width as' the basesupport member 12. The clamping block 14 has an aperture disposed centrally therein and extending thereto frometop to bottom to correspond with the aperture in the base' support 12.

The engine block 11 has a threaded aperture 27 which receives a threaded bolt 17 to secure the base support 12, U-shaped rocker fulcrum 13, and clamping block 14 to the block of the engine. The flat washer 15, and a lock washer 16 are placed between the head ofthe bolt 17 and the clamp block 14. The fiat washer 15 protects the clamp block 14, and the lock washer 16 forrns the usual,

function of locking the bolt` 1 7 imposition with respect The

rocker arms

18 and 18a are identical in structure' and appear on either side ofthe base support as best shownin Figs. 2 andA 3.

bearing surface designed and i adapted to p over the end of a valve stem 23.*

60 y f L "dle or Vbearing surface 30 which coacts with the outersurview of the vdouble .The rockerv arm assembly of this invrntionis shown as'itwould.bemountedman-engine,The push rods and" V`assembly is associated'therewith.l i

.iReferringin greater d etatilf-to the i vSince the rocker arms 18 and lSnare identical in structure, only therocker arm 17.8 'will be described in detail. Rocker arm 18 can be stamped or pressed from steel making it very economical to manufacture. Vlit is genefally of a U-shaped channel design with a push rod receiving rend 28, and a valve stem receiving end 29 extending from the sadde 30 at the central portion thereof. The end 28 has a cupped seat 251 formed thereinto receive and seat Ithe end of a push rodV 22. 'Ihe end 29 has an arcuate abut and slide "The Ulshaped portion ofthe rocker arm hasa sadface of the 'U-shaped rocker fulcrum.V The bearing surface 3 0 is dimensioned so as to form a bearing lit` with the outside surface of the-lJ-shaped rocker f ulcruniso that the bearing surface "30, when in the position as shown',

surface of the `U-shaped rocker fulcrumjand the'` shaped rocker fulcrumfacts as 'abearing therefor.

As fpreviouslydescribed, the U-shaped rocker fulcrum `extends on yeithervsid'e ofthe base support. Each extended p'ortion ofthe fulcrum acts as atbearing sur-facefffor the .-rock en arrnr 18 androcker armilarespectively.

The

rocker arms

18 and 18a are held in bearing engagement with either end of the rocker fulcrum 13 by means of a spring designated generally as 21. The spring V21 has limbs or clips 31 and 31a which are bent in an arcuate manner inwardlyrtoward the body of the spring 21. The spring 21 is positioned between the engine block 11 and the bottom of the base support 12. It has an aperture located in the center thereof which corresponds with the aperture in the base Vsu`pportr12, and receives the bolt 17 therethrough. Therefore. the spring 21 is secured in position Aby being sandwichedgbetween the engine block 11 andthe base support 12. Thespring limbs or clips 31 and 31a engage the underside of the channel shaped

rocker arms

18 and 18a, and assures that the bearing surface 30 and 30av thereof maintain constant engagement with the bearing surface 41 of the rocker fulcrum.

Although spring 21 isa preferred form of the invention, it is to be understood that other spring designs may give comparable results within the broader aspect of the invention.

The cupped seat 24 of the rocker arm 18 has an oil inlet hole 25 in the side thereof. The push rod 22 is hollow and forms a passage for oil from a hydraulic tappet (not shown). The rocker arm 18 has an oil groove 20 positioned transversely thereofin the bearing surface 30. The bearing surface 30 of the U-shaped rocker fulcrum Ymay have the bottom thereofattened as shown at 19. Both the oil groove 20 and the attened surface 19 may be used to facilitate lubrication; however, usually only one or the other is necessary. The oil, as it is forced from the hole 25, is gravity fed to lubricatc the bearing surface 30 of the rocker arm and the bearing surface 30 of the U-shaped rocker support. The rocker arm 18a has acomparable housing 24a, oil hole 25a, and transverse oil groove 20a.

Having described the structure of the double rocker arm assembly, the operation thereof will now be described.

Operation i v The double rocker arm assembly is secured to the engine block 1l by inserting bolt 17 through aperturesin the lock washer 16. the at washer l5, the clamping block 14, the U-shaped rocker fulcrum 13, the base support 12, and the spring member 21, and'threadingY the bolt 17 in the threaded aperture 27 of the engine block. The U-shaped rocker fulcrum assumes the position shown in Fig. 1 and is aligned over the spring clip arms 31 and 31a. Before the bolt 17 is tightenedrit is an easy matter to slip the rocker arms 18 and'18a under the respective spring arms 3l and 31aand the vbearing surfaces 30 and 30a of the rocker arms fit snugly against the bearing surfaces 41 of the U-shaped rocker fulcrum. The bolt 17 can now be tightened to its secured position. The

rocker arms

18 and 18a are now in position to receive the hollow push rods 22 and 22a in

therespective seats

24 and 24a. The ends 29 and 29a of the respective rocker arms engage the valve stems Y23 and 23a. v -A double rocker arm assembly is now in operative position. The push rods 22 and .22a are reciprocated in a vertical direction by mechanism ofthe engine (not shown). The

rocker arms

18 and 18a arethen caused to rock or oscillate about the U-shapedrocker fulcrum 13. This rocking motion is transferred to the valve stems 23 and 23a and causes them to reciprocate vertically and thereby open and close the valves.

sesame., Y Q

It is apparent that the rocker arm 18`is suspended with 1 respect to the rocker arm fulcrum, rather `than being secured thereto or being threaded on arro'cker' arm shaft. The three points of suspension are atv the push rod, spring, and valve stem; The major points of suspension are at the push rod andthe valve stern, and the spring arm is present to merely hold therocker arms in place and assure that the bearing surface 30 of the rocker arm '4 18 rides against the bearing surface 31 of the rocker support.

It can be seen that a very effective rocker arm has been disclosed which has no apertures at the vital bearing area. Therefore, thisY rocker arm is much stronger than rocker arms being presently used. The rocker arm 18 has the further advantage of being easy to manufacture. It is a simple matter to stamp or press the rocker arm 18 since there areno apertures to design for.

It should be readily apparent that the double rocker arm assembly as disclosed greatly reduces the harmonic vibrations present overman'y of the rocker arm assemblies now in use. Having only two rocker arms operating from a rocker supportrather than, for example, eight rocker arms operating on a rocker arm shaft, obviously will reduce the vibration factor.

Another advantage of this double rocker arms assembly over rocker arms presently in use is that only one fastener 17 is necessary to secure two rocker arms in position with respect to the engine. To secure many of the rocker arms now in use to an engine block, it is necessary to have a fastener such as 17 to secure each and every rocker arm.

Although, the double rocker arm assembly as shown is a preferred embodiment of the invention, it is to be understood that within the broader aspect of this invention one rocker arm rather than two could be suspended from the rocker support similar to the member 13, or the member 13 could be extended and two or more rocker arms suspended from either side of the base support 12.

While a preferred embodiment of this invention has been described, it will be understood that other modifications and improvements may be made thereto. Such of these modifications and improvements as incorporate the principles of this invention are to be considered as included in the hereinafter appended claims unless these claims by their language expressly state otherwise.

I claim:

1. A rocker arm assembly comprising; a support means, fulcrum means, means for clamping said fulcrum means to said support means, said fulcrum means having an arcuate bearing surface, rocker arm means, said rocker arm means having an arcuate bearing surface engaging said fulcrum bearing surface, and means cooperatingwith said rocker arm.means whereby said rocker arm is suspended from said fulcrum means.I

2. A rocker arm assembly comprising; a support means,

fulcrum means, means for clamping said fulcrum means to saidv support means, said fulcrum means having an arcuate bearing surface, rocker arm means, said vrocker arm means having an arcuate bearing surface engaging said fulcrum bearing surface, and means including biasing means whereby said rocker arm is suspended from said fulcrum means.

3.- A rocker arm assembly comprising, a support means adapted to be secured to an engine block, said support means having a saddle'formed therein; fulcrum means shaped to seat in said support means saddle, said fulcrum means extending beyond either side of said support means, rocker arm means including a rocker arm engaging each extension of said fulcrum means; means including biasing means whereby said rocker arm is suspended from said fulcrum means, a Yclamping block engaging said fulcrum means and a fastener adapted to' secure said support means, said fulcrum means, said clamping block' and said biasing means rigidly to said engine block asasingle unit.

4. A rocker arm comprising; a generally U-shaped member. said U-shaped member having anges extending from 'either side thereof adapted to engage a push rod and a valve stem respectively, the U-shaped portion of said member having "a bearing surface adaptedto bear against a support means for purposes of suspending it with'respect to an engine, said bearing surface being void of'apertures. Y

5. A rocker arm comprising; a rocker arm means, said rocker arm means having flanges extending from either side thereof adapted to engage a push rod and a Valve stem respectively, said rocker arm means having an arcuate bearing surface adapted to bear against a support means for purposes of suspending it with'respect to an engine, said bearing surface being void of apertures.

6. A rocker arm assembly comprising; a support means adapted to be secured to an engine block, said support means having a saddle formed therein; fulcrum means shaped to seat in said support means saddle, said fulcrum means extending beyond either side of said support means, a clamping block and fastener means adapted to secure said support means and said fulcrum means rigidly to said block; rocker arm means including a rocker arm engaging each extension of said fulcrum means; biasing means, said biasing means having limbs engaging each rocker arm and forcing them into bearing engagement with said fulcrum means extensions.

7. A rocker arm assembly comprising; a support means adapted to be secured to an engine block, said support 'means having an arcuate saddle formed therein; fulcrurn means shaped to seat in said support means saddle, said fulcrum means extending beyond either side of said support means and having arcuate bearing surfaces formed thereon, a clamping block and fastener means adapted to secure said support means and said fulcrum means rigidly to said block; rocker arm means including a rocker arm engaging each extension of said fulcrum means; each rocker arm having an arcuate bearing surface and a pair of anges extending from either end thereof, said rocker arms adapted to engage a pair of push rods and valve stems respectively; biasing means engaging said each rocker arm and forcing their bearing surfaces into bearing engagement with said fulcrum means extensions, said flanges and bearing surfaces providing a three point suspension for said rocker arms. v

8. A rocker arm assembly comprising; a support means, fulcrum means, means for clamping said fulcrum means to said support means, said fulcrum means having a bearing surface, rocker arm means, said rocker arm means having a bearing surface engaging said fulcrum bearing surface, said rocker arm means having a pair of flanges one of which has a housing adapted to engage a push rod, said housing having an aperture therein adapted to receive oil from said push rod to lubricate said bearing surfaces.

9. A rocker arm assembly as in claim 8 wherein said rocker arm bearing surface has an oil groove therein to house lubricant.

l0. A rocker arm assembly comprising: a support means adapted to be seeured to an engine block in a position extending upwardly therefrom; a fulcrum secured to the top of said support means and having an extension extending from at least one side thereof in spaced relation above said engine block; a rocker arm engaging the undersurface of said extension; and biasing means a-t said support and having a limb extending upwardly and engaging said rocker arm forcing it upwardly into bearing engagement with said fulcrum.

l1. A rocker arm assembly comprising: a support means adapted to be secured to an engine block in a position extending upwardly therefrom; a fulcrum secured to the top of said support means and having an extension extending from at least one side thereof in spaced relation above said engine block; a rocker arm engaging the undersurface of said extension; and biasing means at said support and having a limb biased upwardly and inwardly toward said support and engaging'said rocker arm to force it upwardly into bearing engagement with said fulcrum and prevent it from sliding off the end of said fulcrum.

Kytlica Dec. 11, 1923 Harper Nov. 2, 1926