US2111735A - Valve-operating mechanism for internal combustion engines - Google Patents

Description

March 22, 1938. P, RILEY 2,11L735 VALVE OPERATING MECHANISM FOR INTERNAL COMBUSTION ENGNES Filed Jan. 14, 1937 2 Sheets-Shao?l l 23 O 26 2.3 24 Fig 1 24 22@ 6 y T .28 20 .n I 21* 21 :i I- www il? l I 27 Xf l 25 'E 26 2022 27 25 L I "f/. IZ-k \13 l 19 l I 1| 19 Q )1i f1@ w f y I 15 16 o" I w15 \y y Y 14 1 @j www March 22, l938. l VFa RILEY 2,1l,735 J VALVE(OYPERTING MECHANISM FOR INTERNAL COMBUSTION ENGINES Filed Jan. 14, 1957 2 SheJcSShe0t 2 Patented Mar. 22, 193e autres WCHANSM FOR IN- 'rizaNAL coivmUs'rroN ENGINES Percy Riley, Coventry, England Application January 14, 1937, Serial No. 120,639 In Greatritain January 17, 1936 6 Claims.

This invention relates to valve-operating mechanism for internal-combustion engines such as include overhead valves.

The main object is to provide an improved op- `5- erating mechanism with which very satisfactory cam control can be obtained, Whilst difficulties arising from the use of new cylinder gaskets, for example, will be largely obviated, and expansion as wo-rking temperatures are reached will be less prone to interfere with the valve clearances. Many of the advantages obtainable with an overhead camshaft can be obtained, by means of the present invention, without the expense and diculties of operation of overhead camshafts being encountered.

Valve gear for an internalfcombustion engine with an overhead valve, according to the invention, includes a rotatableV crank, eccentric, cam or other member, a cam bar slidable thereby, and D a rocker tor the valve adapted to be engaged by the profile of the cam bar so as to open the valve on movement of the cam bar in one direction.

In the acccrmianying diagrammatic drawings:-

Figure 1 is a sectional elevation, taken on the line I-l'. of Figure 2, mainly of the cylinder block of. an internal-combustion engine fitted with valve gear according to the invention;

Figure 2 is a fragmentary plan thereof;

Figure 3 is a view similar to Figure l of a modified arrangement; and

Figure 4 is adetail viewof a further modifical tion,

Like numerals indicate like parts throughout the` drawings.

In the construction of Figures 1 and 2 there is illustrated a heini-spherical combustion cham ber l2 with a pair of overhead poppetvalves i3, i3 set at approximately ninety degrees to one another and across the engine. Obviously, however, by the use of different actuating rockers the valves may be set at any desired angle. The drawingsv'show two operating shaftsrili, lli arranged on opposite sides of the engine, and conveniently one of these is disposed where the camshaft would be of an ordinary engine with sideby-side valves or with pushrodoperated overhead valves. Each operating shaft has fast on it a crank-pin or other 'eccentric i5 for each valve disposed on that side ci the engine. VThe eccentric straps l5 are in each case hinged to links il guided in the cylinder block i8 and in turn hinged, respectively, to slidable cam bars i9. Eachcam bar is formed on its non-operative face with a smooth portion 2i] in engagement with an (Cl. 12S-90') abutment 2|. Its operative face has a recessed portion 22 disposed in proximity to the roller 23 on the shorter arm of the associated rocker 2li and joined by a smooth curve to the non-recessed or raised portion 25. The rocker has the longer arm 2S linked at 2l to actuate the adjacent valve, the shorter arm being arranged to engage one end of a common spring means 28 acting on the rocker to urge .the valve tc the closed position.

At the left-hand side of Figure 1 the valve is shown in the closed position, the cam bar being near the bottom of its travel and the recessed portion 22 of the cam bar being engaged by the short arm of the rocker. At the right-hand side of Figure 1 the cam bar is in its raised position V and the non-recessed portion is in engagement with the short arm of the rocker, the latter having been caused to rotate clockwise and thus open the valve.

The abutment 2l in this case is assumed to be a hydraulic one of the kind described and claimed in the specication of my co-pending patent application Serial No. 120,638, filed January 14, 1937. It may obviously, however, take other forms-for example, as shown in Figure 3.

It will be evident too .that use may be made of only a single operating shaft I4, this having one eccentric per valve and each eccentric being associated with its own cam bar and each cam bar with its own rocker. Half the rockers act di- 3 rectly on the adjacent valves, as described in connection with Figures 1 and 2, the remaining Vones being linked to corresponding rockers through which the valves on the remote side of the engine can be actuated.

Whereas the valves in the construction of Figures 1 and 2 are spring-returned, in the construction of Figure 3 they arepostively moved in both directions. Here, each of the rockers 2da, has two short arms 29, 3G carrying rollers which coact with the operative face of the cam bar ida. This includes a recessed portion 22a between two prominent portions 25a, 25ojoining the recessed portion with smooth curves. When the cam bar is in a lowered position, as shown on the left-hand side of Figure 3, the upper arm 29 of the associated rocker is engaged with the upper fiat 25a and the lower arm 30 with the recessed portion 22a, the rocker having been turned in a clockwise direction to the fullest extent to effect closure of the valve. The proled end of the cam bar may be sufciently springy to ensure that the valve is closed on toits seat at an appropriate pressure in these conditions. When the cam bar is fully raised, as shown at the right-hand side of Figure 3, the associated rocker has been rotated in a clockwise direction to the fullest eX- tent to effect opening of the adjacent valve, the upper arm 29 engaging the recessed portion 22a and the lower arm 30 the lower flat 25h.

In this construction the abutments Zla carrying rollers are adapted to be positioned as necessary by means of the bolts 3l.

It will be evident that, as in the construction above described in connection with Figures l and 2, use may be made, if desired, of only a single operating shaft lf3, al1 the rockers being on that side of the engine on which the operating shaft is arranged and half of them being linked to rockers associated with the valves on the remote side of the engine.

The detail View of Figure 4 shows an alternative arrangement whereby a slidable cam bar lh can positively actuate an associated valve I3 in both directions. The cam bar in this case has a recess 22e on one face, to engage one short arm 32 of a rocker 24h, and a lower recess 22d on the other face to co-act with another short arm 33 of the rocker 24h. 34 represents a xed but adjustable abutment, and 35 a spring-pressed abutment. In the lower position of the cam bar, as shown, the rocker has rotated in an anticlookwise direction to the fullest extent possible to close the valve. As the cam bar rises the rocker is rotated clockwise, as will be easily understood, to eiect opening of the valve. During closing, however, the sideways thrust of the cam bar is taken by the spring-pressed abutment 35, which thus ensures closing the valve on to its seat at an appropriate pressure.

By means of the invention I provide overhead valves for an internal-combustion engine without the size of the engine being materially increased, whilst very satisfactory valve operation can be obtained. Furthermore, in the case of a V-type engine the one operating shaft can be used for actuating the valves of both the cylinder banks, which results in further economy.

What I claim as my invention and desire to secure by Letters Patent of the United States is:-

1. In an internal-combustion engine, an overhead valve, a three-armed rocker having one arm connected to actuate said valve, a rotatable eccentric member, a reciprocable cam bar, and means interconnecting said cam bar' and rotatable member whereby said cam bar will be reciprocated on the rotation of said rotatable member, said cam bar having a profile portion, different parts of which are continuously engaged, respectively, by the other arms of said rocker, such as to effect opening of the valve on movement of the cam bar in one direction and closing thereof on movement of the cam bar in the other direction.

2. In an internal-combustion engine, a valve, a three-armed rocker having one arm connected to actuate said valve, a movable cam bar having two high points spaced apart to alternately engage the two remaining arms of said rocker, said cam bar having between said high points an intermediate low point to receive the two remaining arms of the rocker when the same are not engaged by said high points, and an abutment engaging said cam bar on the face thereof opposite to said high and low points for maintaining the cam bar up against said rocker arms.

3. In an internal combustion engine, a valve, and mechanism for operating said valve, said mechanism comprising, a reciprocating cam bar having a resilient floating upper end portion provided with high and low points on one face thereof, valve actuating means engaged by said high and low points, and an abutment positioned to engage the face of said resilient portion of the cam bar opposite to said high and low points whereby to maintain the floating resilient upper portion of said cam bar with the high and low points against said actuating means.

4. In an internal combustion engine, a valve, and mechanism for operating said valve, said mechanism comprising, a movable cam bar having high and low points, valve actuating means engaged alternately by said high and low points, an abutment engaged by the face of said cam bar opposite to said high and low points, said abutment including a support, a block slidably mounted in said support toward and from said cam bar, and means for adjusting said block toward and from the cam bar.

5. In an internal combustion engine, a valve, and mechanism for operating said valve, said mechanism comprising, a movable cam bar having high and low points, valve actuating means acted on by said high and low points, a support, a movable block in said support having a movement toward and from said caml bar, means for adjusting said block in said support toward and from said cam bar, and anti-friction means carried by said block and engaging said cam bar on the face thereof opposite to said high and low points.

6. In an internal combustion engine, a valve, and mechanism for operating said valve, said mechanism comprising, a movable cam bar, valve actuating means moved by the cam portion of said bar, abutments disposed on opposite sides of said cam bar, means for adjusting one of said abutments toward and from the cam bar, and means for yieldably urging the other abutment toward the cam bar.

PERCY RILEY.

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