US957730A - Valve for internal-combustion engines. - Google Patents

Description

E. W. BRADY. VALVE FOR INTER NAL COMBUSTION ENGINES.

l APPLICATION FILED JULY 8, 1907. gff.

WITNESSES:

F. W. BRADY.

'VALVE FOR INTERNAL GOMBUSTION ENGINES.

APPLICATION FILED JULY 8, 1907.

Patented May i0, i910.

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WITNES:

FRANCIS W. BRADY, OF NEW YORK, N. Y.

VALV FOR INTERNAL-CMBUSTION ENGINES.

naman.

' Specification of Letters Patent.

Patented May 10, 1910.

Application filed July 8, 1907. Serial No. 382,701.

l To all whom it may concern.

Be it known that I, F annals lV. BRADY, a citizen of the United States, residing at New York, in the county and State of `New York, have invented certain new and uset'ul Improvements in Valves for internal-Combastion Engines; and I do hereby declare the toilowing tothe a full, clear, and exact description of the, invention, such as will en. able othersskilled in the art to which it appertains to malte and use the same.

In the construction of internal combustion engines, Where, l have attempted to use an exhaust valve which not operated mechan ically from the engine shaft, but isoperated automatically by the pressure of the exhaust gases themselves. l have encountered diiiiculties, particularly Where the engine is de'- signed for great power, lor to runat high speed, arising from the fact that the throw of the Valve, resulting from the pressure of the outgoing gases, is very violent and so destroys the spring or cushion against which the valve works in its outward movement. The construction forming the subject matter of this application has been designed to overcome'these diiculties, and it is generally applicable to the constrnctionyot valves operatf ing autometieally b v the pressure of the niovii'lg gases.

The construction and mode of operation of my improved valve will be understood from a consideration el the accompanying drawings and this specification.

ln the drawings, Figure l illustrates an exhaust 'valve embodying my invention applied to an internal combustion engine; Fig.

2 isa cross-section on the line Q-Z o'l Fig. l Fig. 3 is a modified form of exhaust valve, shown in cross-section; Fig. 4 is a showing, in cross ection, of an inlet valve embodying my invention; and Figs. 5 and (l illustrate further modified forms.

In Fig. l the valve construction, embodying` my invention, is shown as applied to an internal combustion engine A. This engine forms no part of my present invention and its general construction will be understood from the drawing without detailed description. ln the head of the cylinder body of the engine a valve chamber r1. separated from the combustion chamber ot' the engine by the valve which is operated, through the rocking-arm c, from the engine shaft. inthe valve chamber o the inlet pipe l terminates', and on the other side of the chamber a, is formed the outlet or exhaust valve chamber c. This chamber is separated from the chamber a by suitable partitions carrying the seated valves f and f, the stems of which are rigidly connected togetherrby the lever y pivoted on the bracket L projecting from the cylinder body. lt Will be observe that the surface ofthe v'alve j' which opens outwardly is greater than the surface of the valve j" which opensI inwardly; and that the valves are held in the position shown in Fig. l b v the spring z'.

In operation the exhaust gases pass from the engine cylinder across the Valve b into the chamber e and against the surfaces of the valves f and f. `The preponde ance of pressure upon the greater surface f the valve f throws open this valve againjt the action of the spring `and the movement of the valve is transmitted through the lever r/ to the valve f. whi'ch. in opening against the pressureI ol theexhanst gases, cushions the valve ff, relative extent of the surt'aces of th'ejtivo val yes and f ma y be regulated to suit/the l,circnmstances governing any particular design, so that the exhaust valve may be nnule to open with the desired force and speed. Y

ln the construction shown in Fig. 3, the valve surfaces f and j", instead of being connected through their stems by the lever g are mounted on a single stem mf. The de-yy signer may, in particular cases, use a spring to seat the valves, but ordinarily the Weight ot the valve structure is suliicient for that purpose.

ln Fig. l-. r is an inlet chamber adapted to communicate through the valves s s with an engine cylinder. ln this case the valve stems are intended to be connected together in the same manner as the valve stems of Fig. l, but the larger valve .s' is opened inwardly by the pressure of the gases and the smaller valve s opens outwardly against that pressure.

ln the. construction shown in Fig. 5 the collars n and n. on the stem of the valve t, instead of fitting tightly the end of the lever y, are so placed as to give a' limitedk play to the valve, thusconstituting a lost motion device. in this case the valve t opens freely under the pressure ot' the gases until the collar 71, strikes the end of the lever arm, whereupon the cushioning by the valve t becomeselteetivc. lt Will he observed that in this construction the valve surface t may be equal to, greater than, or less than the valve surface z5.

ln the construction shown in Fig. 6 the arm o of the lever g is longer than the arm c', whereby the surface of the valve u may be smaller than the surface of the valve u.

l These several structures have each its own advantage under particular circumstances, but they are all characterized by the fact that the valve opening under the pressure ot the gases is cushioned by a snr-face opening against that pressure to which surface the movement ot the opening valve is transmitted.

By means of this invention, l am able to successfully employv in an internal combus- -tion engine 'et large power and high speed a valve which is automaticallj7 actuated by the pressure of the gases, thereby retaining the many advantages and the large factor of safety inherentin such a valve structure.

l. ln an internal combustion engine7 a cointnistion chamber havini@T a port throngh which the contents o' the combustion chamber as a whole pass dni-ing the rcciprocaticn ol' the piston, a valve vopening in the direction ot lio'w of the gases and actuated b v the movement thereof and controlling` said port, and cushioning incchai'iisin for Said valve comprisingh a surface operativelj,T connected therewith and movingY against. the pressure of the gases; substantially as described.

2.111 an internal combustion enc'ine, a`

1 -c` combustion chamber havingl a port through ber as a Whole. pass during the reeiprocatien oi' the piston, a valve actuated by the movement of the gases and controlling said'port, a second valve opening against the pressure of thegases, and connection mechanism between said valves for transmitting the movement of the r'st valve to the second, vvhere`` by the movement of the rst valve is ioned; substantiallf,7 as described.

3. In an internal combustion engine, a combustion chamber having a port through which the contents of the combustion chambei as 'a Whole pass during the reciprocation of thepiston, a valve actuated by the movement ofthe gases and controlling' said port, a surface arranged to move aga/inst the pressure of the gases, and connecting mechanism between the valve and said surface, said connecting mechanism including a lost motion device; substantially as described.

et. An engine having,r a valve opening ontvfardlv from the combustion chamber and thronghwhich the contents of that chamber are exhausted, said valve being` actnatcdby the pressure of the confined gases on the exhanst stroke o the piston. in combination With means for cushioning` said valve comi rising a ple-,te nnahanically connected thereto and nnvvfn i' against the pressure of the said gases; su antiallv as described.

allii'v inf. signature,

onshl'n testimony whereof in presence of tivo Witnesses.

FRANCS 'WA BRADY f'itnesses Bnnonss A. Conner, LEW. C. Moons,

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