US1096900A - Valve mechanism for internal-combustion engines. - Google Patents

Description

. I G. FORNAOA.

VALVE MECHANISM FOR INTERNAL CQMBU STION ENGINES.

' APPLICATION FILED DEG. 17,1012, I 1,()96,9()O Patented May 19, 1914.

3 SHEETS-SHEET 1.

N G.FORNAOA.

VALVE MECHANISM FOR INTERNAL COMBUSTION ENGINES.

APPLICATION FILED DEG.17,1912.

Patented May 19, 1914.

LO9&900.

3 SHEETS-SHEET 2.

I GJORNAGA. VALVE MECHANISM FOR INTERNAL COMBUSTION ENGINES. APPLIGATION'IIILIID DEO.17,\1912.' 1 096 900 Patented May 19, 191% 3 SHEETS-S HEBT 3.

I wnmzss s INVENTOR ,5 By (/INZ L. w? 1 I HIS ATTORNEYS GUIDO FORNACA, OF. TURIN, ITALY.

. VALVE MECHANISM FOR INTERNAL-.COMBUSTIQNENGINES.

, Specification of Letters Patent.

Patented May 19, 19 14.

' Application filed December 17, 1912. Serial No. 737,173.

To all whom it may concern Be 1t known t at I, (311100 'FORNACA, a

subject of the King of Italy, residing at Turin, Italy, have invented certain new and useful Improvements in Valve Mechanism for Internal-Combustion Engines, of which the following is a full, clear, and exact specification.

This invention relates tointernal combustion engines and more particularly has reference to means for varying the extent of openin of a valve, according to the power desire to be developed by the engine.

As specificallyshown herein, the extent of opening of a valve may be varied without varying the time of opening and closing the valve in the cycle of operation of the engine, it being seen that the farther the valve, is

opened the greater the charge of gas whichcan be admitted or discharged from the engine, such as air, combustible mixture, liquid fuel, exhaust gases, etc. Thereby, it is possible to obtain a very effective regulation of air-internal combustion engine by the increasedrange of valve control afforded by this invention, and without affecting the predetermined timing of the various parts of the cycle.

The invention is applicable to either two cycle, four cycle or other'types of engines, in connection with valves of various types, and isspecifically shown herein applied to a two cycle engine of the Diesel type, though it will be understood that the invention is not restricted to engines of this type or cycle, or to puppet valves, which are illustrated herein for purposes of convenience.

In carrying out the invention I prefer to operate the valves from an oscillating shaft, and the invention is especially concerned with connections for manually varying the angle of oscillation of the shaft either during the operation of the engine or while the engine is at rest, and also permitting a governor to'automatically vary the angle of oscillation of the shaftwhile the engine is running in accordance with the speed. The greater the angle of oscillation of the sh aft the wider the valve will be opened, and vice versa, without varyingtho instant of opening or closing;

The invention will be more fully understood in connection with the description of the accompanying drawings, whereinv Figure 1 is a vertical section of a two-cycle Diesel engine taken through the valve for admitting air for scavenging the cylinder; Fig. 2 is a vertical section taken through the center of the fuel valve with parts of the latter omitted; Fig. 3 is a detail on an en larged scale illustrating the movements of the oscillating shaft for controlling a valve; Fig. 4 1s a diagram illustrating the variatrons effected by adjustment; F i'g. 5 shows a slight modification of the adjusting means, and Fig. (3 'is a detail showing means for controlling a valve automatically by a governor'.

The two cycle engine indicated in Figs. 1 and 2, representing in general the Diesel or similar high speed type, comprises a base 1 carrying the cylinder 2. 3 is the piston, t

.the exhaust port controlled by the piston 3,

which latter drives the engine shaft through the connecting rod 5. It will be understood that suitable cooling means, 6, of any approved construction or arrangement will be provided. The air valve chamber 7 is shown provided with a valve head 8 connected to the stem 9, the exterior end of which carries the roller 10. The valve head 8 is seated by the spring 11 having one end bearing on the stationary abutment 12, and its other end in engagement with the movable guide 13 secured proximate the exterior end of the stem 9. The valve chamber, and the valve are exteriorly detachable through the cylinder head. The oscillating or reciprocatory member 14 is provided with cam surfaces arranged for opening the valve 8 in a down ward direction, and for permitting the valve 8 to be closed in its upward position under action of thespring 11. For securing these objects the member 14 is provided with the downwardly protruding cam portion 15 located to the right of the center thereof, with npivzirdly extending caln surfaces leading from both sides thereof, and said member 14 is mounted on the idle link 16 at one end thereof, the rcmainingend of the member 14 being pivoted to the arm 17 fixed to the oscillating shaft 18, constituting a parallel f motion. The shaft 18 is oscillated "by the timing shaft 20, suitably geared to or otherpitman. 21 connected at one end by a crank 1t) to the timing shaft 20, the other end be ing pivoted to the link 22, the remaining end of the link 22 being pivoted to the lever 23,-adjusted by means of the adjustment nut 24: and link'31. The slide member '25 attached .to the link or pitman 21 is adapted to reciprocate within f the rocking fork or arminember 26, the latter being rigidly secured to the oscillating shaft 18, Thus, for anygiven adjustment of the adjusting means 24, the fork 26 will be oscillated upon the rotation of the timing shaft 20, thereby oscillating the shaft 18,. arm-17 and cam member 14, controlling the valve 8.

The fuel is likewise similarly controlled by the oscillating shaft 18 to which the cam 27 is fixed, thelatter cooperating with the bell crank lever 28 for tripping the stem 29 of the needle. valve 30. Fig. 2 indicates the fuel valve 30 in open position, whereas the downwardly, the link 22 will be moved up wardly relatively to the timing shaft,.thereby moving the pivot 32 of oscillation of the pitman 21 upwardly; hence, for a complete rotation of the timing shaft 20, the are of oscillation of the fork 26 will be decreased; The instantsof opening of the fuel and scavenging valves will be, practically unchanged; likewise, the instants of closing of said valves. Again, upon moving the arm 31 of the adjustable lever 23' upwardly, the pivot 32 of oscillation of the oscillating le- .ver 21 will be moved downwardly thereby increasing thearc of oscillation of the fork.

member 26, the angle of oscillation of the shaft 18, and hence the extent of-opening of the fuel and scavenging valves.

The'schematic diagram shown in Fig. 4 indicates the arcs of movement and durations of the parts as arranged in Fig. 3. The line 0 b may represent the time of opening of the air valve and also the time of closing 'of said valve. 1 The liner; Zfimay represent the time of opening of the fuelvalve and the valves.

likewise the time of closing of said valve. The lines 0 0 and 0 c representthe extreme positions of the fork, as for maximum oscillation and thereby maximum opening of Thus the duration of opening of the air valve is twice'the angle 7) 0 0; likewise, the duration of opening of the fuel valve is twice the angle b 0 c. The dotted lines 0 d and 0 d represent positions for lesser openings, in which'cascs the angle of duration of opening of the air valve is represented by twice the angle 7) 0 d, and the period of admission of, fuel is represented Upon 1 by twice the angle 12 o d. It will thus seen that opening of a valve can be varied without changing its timing.

extent of opening of a valve without changing its time of opening and closing in the cycle, is especially advantageous. when applied to the Diesel type of engine herein shown. In this engine, as will be seen from Fig. 4-, air is admitted at the line I), on movement tothe right toward d or c and cut off on the return movement at b. extent of. opening is therefore governed. by twice the distance from Z) to the end of the oscillation. The fuel is likewise admitted at Z) during oscillatory movement-to the left, and cut off at 5 during the oscillation to the right, irrespective of, the amplitude of the oscillation from b, whether to d or 0, or any other point.

The provision of means for varying the I The I Regulation of. the valve openings, to control the quantity of air and fuel, and which can be done simultaneously doesfnot affect the combustion at different speeds, and powers. By this invention, the

control and efliciency of the engine is very much improved. v

In Fig. 5 is represented a modificatlon of the connections between the oscillating le--- ver 21 and the oscillating shaft 18, this figure showing the arm 33 fixed to the oscillating shaft 18, and a link 34 pivoted to the arm 33 and to the lever 21, the remaining The operation of the two-cycle engine represented in Figs. 1 and 2 will be clear from the above description. lln'the' operaparts being substantially as shown in Fig. 3. l

tion of this type of engine the piston will open the exhaust near the end of the down orworking stroke, the scavengmg air being admitted prior to the closing of the exhaust upon the returning or upward movement of the piston, the air which is retained-in the cylinder after the exhaust is closed being compressed by the piston, the fuel being admitted into the cylinder when the piston is descending and fired at a desired instant, and the exhaust again opened by the piston at a point near its lowest position, these two cycles being repeated as described; It will be seen that the air valve in the engine de'- scribed is opened at a different stage thanthe fuel valve.

ltwill be clear that the adjustment arm 23 may be regulated by an: tomatic means, as is'indicated in Fig. 6, such as a centrifugal governor 35 connected to the arm 23 by link 86, lever 37 and arm 31, whereby at low speed the opening of the respective valves will be increased, and the same decreased at high speed. It will also be clear that my valve regulating arrangement is applicable to the control .of but a single valve, and also to the simultaneou's control of a plurality of valves in one or more cylinders.

position of the however, that the parallel motion valve ac-' tuating vmechanism is peculiarly susceptible to regulation by my improved means, inasmuch as the cam can be made to strike the roller in opening and leave the roller in closing at the same time in the cycle, while' 'the stroke of the cam while in contact with the roller and thereby the opening of the valve will be varied without affecting any of the other operations. Such a system of valve operation in connection with the fourggmcle engine would be of particular advantage in controlling the power of the engine simply by the opening of the valves. It be ing seen that the power could be varied by varying the valve opening within wide limits.

Various modifications and changes in the anechanical arrangements herein shown may "also be made without departing from the scope of the invention.

Havin thus described my invention, I

to secure by Letters Patent, is

1. In agcomb'ustion engine, the combination Wlthpfi, valve, of means for operating said valve in predetermined relation to the cycle of the engine, and means for varying the extent of valve opening without affecting the times of opening and closing.

2. In a combustion engine, the combination with a puppet valve, of means for operating said valve in'predetermined relation to the cycle of the engine, and means for varying the extent of valve opening without affecting the times of opening and to closing.

3. In a combustion engine, the combination with an inlet valve, of means for operating said valve in predetermined relation to the cycle of the engine, and means for varyso. ing the extent of valve opening without affecting the times of opening and closing.

4. In a combustion engine, the combinationwith an inlet puppet valve, of means for operating said valve in redetermined relation to the cycle of the engine, and means for varying the extent of valve opening without affecting the times of ope'ning'and closing.

' 5. In combustion engine, the combination with a valve, of a cam for operating said valve in predeteg'mined relation to the cycle of the engine, and means for varying the throw of the cam to vary thevalv open;

ing without aflecting the times of opening and closing. I

declare t at what I claim as new and desire 6. In a combustion engine, the combination with a valve, of oscillatory cam means for opening and closing said valve at predetermined times, and means for varying the stroke of said oscillatory means to vary 0 the extent of opening of said valveindependent of said times.

7. In an engine, the combination with a valve, of an oscillatory'cam member for opening and closing said valve at ,predetermined instants, and means for oscillating said cam member in synchronism with the rotation of the engine shaft, said last named means being adjustable to vary the stroke of oscillation from a fixed point of said cam member, without altering the times of opening and closing. a

8. In an engine, the combination with a valve, of oscillatory means for opening and closing said valve at predetermined instants, and means for oscillating said means in, synchronism with the shaft of the engine, said lastsnamed means being adjustable to vary the extent of oscillation of said oscillatory means without altering the times of 9Q opening and closing. i

9. In an engine, the combination. with a valve, of oscillatory means for opening and closing said valve at predetermined instants, and means for oscillating said means in synchronism with the shaft of the engine, said means comprising an adjustable part for varying the extent of oscillation of said means without altering the times of opening and closing. a

10. In an engine, the combination with a valve, of an oscillatory device for opening and closing said valve at predetermined instants, means for oscillating said device, said means comprising a shaft driven by the engine, a pitman and' an adjustable connection between said pitman and said oscilla" tory device for varying the stroke of oscillation of said device from a fixed point with out altering the times of opening and closing. no

11. In an engine, the combination with a valve, of an oscillatory device foropening and closing said valve, at predetermined inv stants, means for oscillating said device, said means comprising a shaft driven by the engine, a pitman, and a connection between said pitman and said oscillatory device, and. means for ad ustmg said pitman and said connection to vary the oscillation of said device to vary the extent of opening of 129 said valve without altering the times of opening and closing.

12. In an engine,the combination with a valve, of actuating means comprising an oscillatory shaft, means oscillated by said 1 5 shaft for moving said valve, and a pitman for oscillating said shaft,'t he connection between the p tman and shaft'beingaintermediate its ends.

133111 an engine, the, combination with a no shaft for moving said valve,

valve, of actuating means comprising an oscillatory shaft, means oscillated by said a pitman-for oscillating said shaft, the connection between the pitman and shaft being intermediate its ends, and means for adjusting said pitman and connection to vary the oscillation of said device.

14. In an engine,.the combination with a 'valve, of oscillatory means for actuating said valve comprising a shaft, a pitinan ro-' tatable at one end in synchro-nism with the engine shaft for oscillating" said shaft, a pivotal support for the other end of said pitman, and an actuating-connection between'said pitinan and said valve actuating shaft.

binatio-n a fuel inlet valve, a scavenging blast admission valve, single means for opening and closing said valves respectively atredetermined instants in the cycle of 'operation of the engine, and means for varying the extent of valve opening without altering the instants of opening and closing.

16. In an engine, the combination with a valve, of a crank and a pitman, the crank beingv driven in synchronism with the engine shaft, a cam driven by said pitman adapted to actuate said valve, and means for effecting "relative adjustment between said pitnian and said cam for variably controlling said valve.

17. In an engine,,the combination of a valve having a forcausing said elementto reciprocate, said other end of said arm.

means comprising an oscillatory device adapted to engage said reciprocatory element, a shaft carrying said oscillatory device, an'arm having one end eccentrically .mounted on the timingshaft of the engine,

and means for pivotally supporting the 18. In an engine, the combination of a valve having a i'eciprora tory element, means for causing said element to reciprocate, said means comprising an oscillatory ment, a shaft carrying said pivotally supporting member, and an actuating connection. be-

adapted to engage said i-eciprocatory eleoscillatory device, an arm' having one end eccentrically mounted on the timing shaft of the engine, and adjustable nieansfor pivotally supporting the other end of said arm.

19. In an engine, the-combination. of avalve and a cam for actuating said valve, member rotated at one end in synchronism with the shaft of the engine, means for the other end of said tween said member and said cam.

20. In an engine, the

pitman, means for rotating one end of said pitinau in synchronisin with the'shaft of the engine, a link pivotally supporting the other 15. A two cycle engine comprising in come reciprocatory clement, means tion'with a valve, of-

device.-

combination of a. valve and a. cam for actuating said valve, a

' oscillatory controlling means end of said pitman, means for adjustingthe' position of said link relatively to; the i'o-.. .tated end of said pitman,

22. In a combustion engine, 'the'combination with a valve, of a cam, an oscillatory shaft for actuating said cam, a pitman-for actuating said oscillatory shaft and connected to said oscillatory shaft, a rotatable connection between one end of said pitman and the engine shaft, and an adjustable fulcrum support for the pitinan.

23. In a combustion engine,

tuating said cam, a pitman for actuating said shaft and connected to said shaft,-a ropitmanand said a the combina-- tion with a valve, of a cam, a shaft for ac tatable connection between one end of said I pitman and the engine shaft, and apivotal support for the other end of the p'itniian.

24. In a combustion engine, tion with a valve, of a cam, parallel links supporting said cam, a rock shaft for actuating said cam,and a pitman driven in syn;

chroqii'sni' with the engine shaft for actuating said rock shaft;

In'a combustion engine, the combination with a puppet valve, of a cam, parallel links snpporting said cam, 'a rock shaft for actuating said cam, and a pitman driven in svnchronism with the engine shaftfor acti'iating said rock shaft.

26. In a combustionengine, the combinaa' cam, parallel links supporting said cam, a rock shaft for actuating said-cam, a pitman drivenin synchronism with the engine shaft for actuating said rock shaft and an adjustable support for said pitinan whereby to vary the movement of said cam to control theopening of the valve.

27. A combustion engine comprising in" combination a fuel inlet valve, a scavenging blast admission valve, oscillatory means for opening said fuel valve at one portion of the valve at another portion and IIIGR-DSffOl varying the amplitude of oscillation of said oscillatory means to vary "the ex'tent of. opening of said valves with out altering their respective timesof opening andclo'sing'. j

28. Thejcombinat en. with a1 cylinder: and

piston, of means for admitting air and fuel,

therefor, and

the combina- 1%- .oscillation andfor opening the scavenging. of the oscillation,

means for varying the amplitude of oscillation of a valve, a rock-shaft for operating tion of said means.

29. A COIllbllStlOI] engine comprising in combination with a fuel valve and a blast scavenging valve, of an oscillatory e0ntrol ling element for admitting fuel at one end of the oscillation and a scavenging blast at the other -end of the oscillation and mean: for varying the extent of oscillation of said 0 element.

30. In aeombustion engine, the combinasaid valve, an arm carried by said rockshaft, a pitlnan slidably engaged by said arm, and means driven in synchronisln with the engine for actuating said itman.

In testimony whereof I a x my signature, in presence of two Witnesses.

. GUIDO FORNACA. Witnesses: GA'rI Annos,

JOCELYN GOUBEYRAN.

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