US1623176A - Valve for internal-combustion engines - Google Patents

Description

0. C. FUNDERBURK VALVE FOR INTERNAL COMBUSTION ENGINES April 5, 1927.

Filed March 10- 1921 2 Sheets-Sheet l I d w 4 M /v ll/114 711!! V INVEN1'UYI EyMc/wZ4 WATT I 1,623,176 P" 1927 o. c. FUNDERBURK VALVE FOR INTERNAL COMBUSTION ENGINES Filed March 10. 1921 2 Sheets-Shea! 2 Q Z v p V74 6 m 2 A .91? 4 I a 76' L k INVEN+IJVI Patented Apr. 5, 1927.;

UNITED STATES 1,623,176 PATENT OFFICE.

one o. runnnnncnmor BOSTON, mssacnusn'rrs.

VALVE FOB mmanar-comnusflc'm ENGINES.

Application filed March 10, 1921. Serial No. 451,082.

My invention relates to valves for internal combustion engmes and to the operatmg mechanism therefor.

. has to do with poppet valves which are operthe conditions under which the engine oper-.

ates. This clearance has rendered the engine noisy because the valve tappet, especiall when the engine is running at high spec strikes the lower end of the valve stem a violent blow which can be distinctly heard. The noise can be reduced by reducing the clearance, but heretofore, so .far as I am aware, it has not been possible to do away with the clearance'altogether, and even the small amount of clearance which is provided where the valves are carefully adjusted, re-

sults in noises which can be'distinctly heard. In fact, it is commonly said that every engine has one noisy valve by which is meant that one valve always makes more noise than the others, and that its sound catches the ear so that if this valve is readjusted to produce less noise, the ear will then hear the valve which is producing the next greatest amount of noise.

Accordingly, my resent invention has for ,its object to pro uce a valve operating mechanism which will altogether eliminate the clearance in question and consequently any noise produced b the valve tappet striking the valve. T iis is accomplished by interposing in the train of mechanism be= tween the-talve and the valve member a column of ,liquid under pressure, the liquid being preferably oil, which being substantially incompressible but variable in quantity, always holds the valve tappetin contact, with the underside of the valve. The result is that the noise in question is altogether eliminated and a remarkable improvement in the quiet running of the engine is produced. a v

The invention will be fully understood from the following description when taken in connection with the accompanying drawing's, and the novel features thereof will be pointed out and clearly defined inthe claims at the close of this specification.

More particularly it t Inthe drawings Fig. 1 is a vertical sectron of a valve operating mechanism embodymg my invention.

f Fig. 2. is a section on line22 of Figure 1.

Fig. 3 is a view similar to Figure 1 and shows a valve operating mechanism embodymg my invention in modified form.

Fig. 4 is a section on line 44 of Figure 3. Referring now to the drawings, at 11 is shown a poppet valve having a valve stem 12 moving in a removable guide 13 positioned in the engine block. On the valve stem 12 is a collar 15 against which rests the valve spring16, this bein the usual valve spring which operates the valve.

a cam on the usual cam shaft. This cam At 17 is shown acts on a cam roll 18 mounted on the lower I endof asliding member or piston 19 which,

together with another sliding member or,

piston 20, may be said to form a two-part tappet, the parts being separated by a body or column of liquid which in this case is oil, all as will be'hereina'fter described. It will be understood of course that I do not limitmyself to the use of the roll tappet since any of the well-known types of tappets may be employed.

The upper member 20 is provided with a Stem 21 which is always in contact "with the lower end of the valve stem 12. The valve tap et members 19 and 20 are both cylindrica in form, and in fact form hollow pistons which travel in a tubular cylinder 22 in the engine casing; The proximate faces of the pistons are hollowed out, as shoyvn at a and b and separated fromeaeh other by the clearance 0. At (l is shown a port through the side wall of the cylinder 22 to permit the entrance of-oil to the space between the two pistons 19 and 20. The port (1 communicateswith an oil passage 6' and pipes 23 and 24. The passage 6 is closed y a valve 25 actuated by a spring 26, the return of oil from the cylinder 22 to the pipe 24 being thus prevented. The stern of this valve 25 is conveniently guided in a screW- threaded'cap 27 inserted in the side of the cylinder 22. The pi e 24 communicates with the pressure fee oiling system (not shown) of the engine so that oil under pressure flows throughthe pipe 23, passage e, past the valve 25, and through the port d into the space 0 between the proximate faces of the pistons 19 and 20. Being valve stem 12 and the cam follower 18 and cam 17 are always maintained in contact with each other. Oil which leaks by the istons 19and 20 and escapes, is replaced y oil flowing past. the valve 25. When the engine is running, the motion produced by the cam 17 is communicated to the valve 12 through the interposition of the column of oil contained in the space between the proximate faces of the pist0ns'19 and 20. Since liquids are substantially incompressible, the several parts have the effect of a unitary rigid valve stem without any clearance, and all noise from these-parts is completely eliminated. Any expansion due to eat is cared for by the leakage, and contraction is overcome by the pressure in the oil ing system of the engine whiclrheeps the space between the proximate faces of the plstons constantly full of oil.

In Figures 3 and 4, I have shown a slight- 1y modified form of my invention. In these figures, the valve is designated 30, the valve spring 31 and the piston members and 33. The space between the piston members is designated g. A spring 8 is inserted be-.'

tween the piston members to hold them apart. The oil is,s upplied to the space 9 from the passage h in the hollow cam shaft 34 in the following way :At 35is shown one of the bearings for the cam shaft. This bearing is cut away on the interior to form a groove 9' which extends about the interior of the bearing for about 150 degrees. At la is shown a port leading from the interior of the cam shaft, the end of the port being located in position to register with the passsage y' during a considerable part of the revolution of the cam shaft. A pipe 36 leads from the passage j to the space 9 between the proximate faces of the pistons communicating with said space by a series of small ports 1.

From the foregoing itwill be seen that the passage from the oiling system through the hollow bore h of the cam shaft, port is,

, passage in the bearing ring and pipe 36 is open to the space bet-ween the pistons during 150 degrees of the revolution of the cam shaft and is closed during the remainder of the revolution, being closed at the time when the poppet valve 30 is opened by the cam.

It will therefore also be seen that the construction described operates as a positively actuated valve to retain the oil in the 011 column while the cam is opening the valve. Any expansion of the valve stem is'cared for by displacement of oil which is forced back through the passage 36 when the groove registers with the port in the cam shaft through which the oil is fed.

It will be seen in connection with both embodiments of my invention that the device will operate even if there is no oil in the chamber between the pistons, because in that case the pistons will be in contact with each other and will act as a unitary valve tappet, the only dill'erence being that the valve lift will be somewhat diminished. This is an important feature of my invention because the engine will start satisfactorily before there is oil pressure enough in the lubricating system to fill the chambers, and will continue to operate satisfactorily even after the pressure in the lubricating system drops below the pressure necessary to fill the chambers in the valve operating mechanism.

What I claim is 1. The combination with a. poppet valve, of operating mechanism therefor "which includes a column of oil, and mean connecting with the oiling system of the engine for replenishing said column of oil, said replenishing means comprising a cam shaftprovided' with a lon itndinal opening through which oil is supplied under pressure, a radial assage leading from said lon itudinal opemng, and means for placing said radial passage in communication with said column of oil'during a part of each revolution of said shaft.

2; In combination with a poppet valve, a valve spring therefor and a cam shaft having a cam thereon, a valve tappet in two parts, a column of oil separating said two parts and means for replenishing the column of oil which includes a longitudinal opening in said cam shaft through which oil is supplied under pressure, a radial passage leading from said longitudinal opening, an

annular bearing on said shaft having a groove oflimited extent on its interior surface, said radial passage being in communication with said g'roove durin a part of each revolution of said shaft and c osed when said valve is opened by said cam, and means for ion placing said groove in communication with said column of oil. A V 3 In testimony whereof I affix my signature.

OTIS C. FUNDERBURK.

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