US1110921A - Valve mechanism for gas-engines. - Google Patents

Description

vh Tl nu 'SOR- GA" EGNES.

APPLICATION FILED SSP VALVE MEG HANSM atented Sept. 15, 1914.

2 SHEETS-SHEET l.

f1 TTURNEY WE A. GILL.

VALVE MECHANISM FOR GAS ENGINES.

APPLICATION FILED SEPT.21,1012, f

jig@ A TTOH/VEY rar-nur 'il'i A. GILL, GF PORTLAND, GREGON, ASSEGNO?, OF ONE-HALF T0 FRED A. COUR,

OF PORTLAND, OREGON. n I

VALVE MECHNISM FOR GAS-ENGINES.

.Specification of Letters Patent.

rented Sent. ifi, 2l

.application filed September 21, 1912. Serial No. 721,698.

Be it known that i. lYiLLiin fr. Giu., a citizen or" the United States. and a resident of Portland.A count) ot' iulnoniali, and Stare or" Oregon, have-invented a nevv and useful improvement in `Valve Mechanism ot Gas-Engines. ot' which the oilmving is a specification.

This invention relates to the valve mechanism of internal combustion engines of the four-cycle type.

he purposes of my invention are as follows: to eliminate anir spring control action of the valve, and to use a slide valve mechanism positively driven, of simple construction, adapted to allow for expansion .vithout sacriiicing gas-tight fit; also to provide for a constant gas-tigl'it lit of the valves, by automatically regrinding them to the surface ofthe cham-ber on which they are seated, and by providing means ei'ecting an automatic take-up as the valves are Worn in service; also to provide iforconsiant, automat-ic7 eective lubrication, and to render the valve action practically noiseless, and to provide valve operating means including a fixed s. aft and bell crank and link connections adapted to be positioned on the dead-center when the explosion' occurs. I attain these and other incidental features by means of the mechanism illustrated in the accompanying drawings, in which Y Figure l is a vertical longitudinal section of a tourrycle vertical gas engine embodying my invention; Fig'. 2 is a sectional Jfront elevation of the valve mechanism or' a gas engine slimving the relative position assumed by the various parts at the beginning of the first phase, that. is, when the piston reaches the upper end ofits exhaust stroke, the ex haust valve just Closing and the inlet valvev i i to i-onn'ncnre opening; Figs. S3, 4 and views similar to Fig. 2` ;`1o\ving the meel :mism in'iliiierentphasesy ot' its o tioned during the first phase, that is, at a point during the intake or rhargingstroke, the intake port heini;A openerL and the piston going down; the pison in 'this case being' positioned about midway in its cylinder on its downward stroke; i? 4 shows the approximate position of when the piston is at the beginning of its explosion stroke; Fig. 5 shows the parte 55. positioned in their last-fphase.- that is.; ai the approximate n. as follows. viz: Fig. 3 shows he parts the valve mechanism' end of a cycie'of motion of the valve niemliers and the operating mechanism thereof; the exhaust port for scavenging 'the burned frases from the c vlinder sliovrn opened, such opening being effected during' the inter val that the piston is rising, and the piston (not shown) .is positioned approximately midvfa;7 in its cylinder on its npwairlstroke; Fig. (3 is a detailed perspective View of the parts constituting the 'valves anc. the stems of my device, the parts beinge shown as separated. but relatively connected by broken lines; Fig. T is a seca-ion on line Ahcef Fig. l; and Fig. 8 is a bottom View of one of 'the sliding valves showing the arrangement of the slot in which the valve stein bears.

I ain-aware' that positiveljv7 driven piston vaives have heretofore been used. but in all such cases no provision was made for talring up the wear. which invarialfl.Y occurs both on the inner Walls of the casing and the outer surface of the valves, Without the use of snap rings. Furthermore, since alleviance forexpansion must be made in valves ot the type referred to, it is veryv diiiicult to secure a gas-tight fit. Another objection to said valves was that efficient lubricating means have not been provided. These object-ions have been overcome in my improved valve mechanism. described as :t'olloi'vs: The gas engine, a., is of tie usual construction, embodying a cyiinderchamber a2, in which reciprocates a, piston b, driving a crank c, integral with JEhe driven'or engine shaft c. B'l'y valve mechanism is actuated by a pair ot' tivo to one meshing gears [Z and which rotate a valve crank shaft f. The latter has a pair of crank-arms g and iz, the crank arm y being positioned a Aquarter or" a revolution ahead of the crank arm z. Above and to one side of the valve operating crank shaft, f.`is located a fixed shaft i, on which is fulcrumed a pair or" bell cranlt levers or rocker arms, y' and 7c, connected to the crank-arms y and /z` of the valve shaft by the links m and a respectively. To the rocker arms j and "l are further attached the links o and p, unich are connected to the valve stems q and r respectively for actuating lthe valves. Said rocker arms are so arranged :hat the Wrist pins, j', je', will be moved a' quarter` of a circle during each revolution of the crankshaft j'. The extreme uppermost and lower most positionsV of the Wrist pin j areshovvn if; Fig.l 1. The wrist pin 1c has the same relative movements -as the pin j. The pivotal connections between the ends of the links, m, 0, n, p, and thc rocker'arms are vSoilocated with respect to the fulcrum of the latter as to impart to said link ends equal angular displacement but unequal angular velocity, to thereby give to the valve member or members a non-uniformly varying motion so timed as to cause the movement of the valves to be retarded during the interval the valves are positioned to entirely close or entirely. open the inlet or exhaust ports of the valve chamber, and accelerated during the interval the valve -members are so positioned as to partially uncover said ports; that is to say, as when the ends of the I valvesy hav'eftraveled approximately to the point of starting Ato uncoveror to cover the ports. The object of the described valve motion Ais to cause a quick opening and closing of the valveports, and particularly to avoid the so-called wire drawingl effect in the opening and closing of the valves. It will be noticed that the fixed Shaft c is alined with the common center of mechanism of the valve. The object of this pari ticular location of said ixed shaft `is this:

' heads valves, a, t, reciprocate within a va ve chamfeo When the explosion occurs, the connecting parts between said fixed shaft and the valves will be approximately onA a dead center,

thereby causing the shock of such explosion to be mostly taken up by the ixed shaft z', instead of having it transferred to the v l crank-shaft f, y,which wort-1d necessitate a much heavier constuetion f the latter. On the valve-stems, q and 1', are mounted the reciprocating or sliding valves, 8, t, in

such manner that the" valvesmay have a` slight lateral play, as apparent from Fig. 6.'

To this end the valve-stems gv and v' are made with reduced portions, g2, r2, nehr the top, so as to be free to -move laterall from the q', o', which maybe inse led in the slotsl's, t', at the base of the vals. The

ber, the latter being provided ith two openings y and' e, each extending nearly half way around the chamber, of which g/ constitutes the exhaustport and a the intake port.' '-'zIhe valves, s, t, are approximately semicylindrical, their flat faces being adapted to slide against each other. -The valves s, t, may be said to be members of a valve-unit. A plate u, inserted in the groove o of the valve 8,. is forced continually outward by the springs fw, so as to cause`the outer or cylindrical faces ofthe twoivalves to bear .constantly against the'walls of the valve chamber, w, thereby automatically taking up any wear, as well as maintaining a gastight joint between the inner facesof the two valves. The bottom of the valve chamber ai is closed by acylindrical head l and constitutes an oil reservoir, and the valves dip in theA oil in their down position. The oil is drawn into the chamber a: from the reservoir 6, in the base of the crank case a',

through a `tube 2v Said tube is provided with a heclrfvalve at 3. which permits 'a flow an upward direction only. The oil i is draw-n up into the chamber by the up-v ward movement of the valves, and overows through 'the stand pipe 4, as Obvious; during the downward movement' of the valves the oil in the bottom of the Valve chamber is forced up, thus insuring an etlicient lubrication of the valve mechanism.

-The plate, a, in fact performs lthe same functions' as a piston ring; but when the explosion occurs, the gas which will have penetrated between ythe flat faces of the valves will drive them still more forcibly against the walls of the chamber therebyv hold said valves against their seats.'

2. In a valve mechanism, a valve chamber, two approximately semicylindrical valves lreciprocating in such chamber, the inner faces of such valves adapted to slide against each other, means for operating the valves, andv means for preventing the passage of gas between the inner faces of the valves,

said last mentioned `means adapted to hold said valves against their seats. I

3. In a valve mechanism, a valve chamber, two approximately semicyl'indrical valves reciprocating in-such chamber side by side; means for operating the valves; a plate movably seated in the inner face of one of said valves and adapted to bear on the opposedface of the other valve; and means for causing said plate to bear constantly against the opposed face of the other valve.-

4. In a valve mechanism, a valve chamber, two approximately semicylindrical valves reciprocating in said chamber side by side; means for operating the valves; means for preventing -the passage of gas between the inner faces of the valves; said means adapted lto hold said valves against their seats; Avalve stems; and means for, connecting @the stems withl the valves adapted to permit the latter. lateral movement.

,ll. il". 5. In a valve mechanism, a valve chamber,

two approximately ,semicylindrical valvfps Areciprocating in said chamber side by side; means for operatingthesvalves; a plate mo ably seated in the xface of one of saidivalvgs and adapted to bear on the opposed aci Mtl' l faces of the valves, said means adapted toy 95 nemesi the vaives adapted to permit; the latter aeral movement.

T. En e. vaive mechanism, a valve chamber, two approximately semicylindrical Vaives reciprocating in said chamber side by side; means for operating the valves; a plete movably seated in the inner face of one of seid valves and adapted to bear on the opposed face of the other Valve; means for causing said plate te bear constantly against the op operates as a su ing oi, and the auomatieely effec 9, En e faire name-er, suon passage sie -eethe vali-fes, said meer valves i

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