US1078286A - Gas-engine. - Google Patents

Description

L. ILLMER, JR.

GAS ENGINE.

APPLiuATIoN FILED APHA 1907,

L. ILLMBR, JR.

GAS ENGINE.

APPLICATTON FILED APRA, 1907.

l yPatented Nov. 11, 1913.

5 SHEBTSSHBET 2V.

W/TNESSES WCW 294 D M@ ffm/l' Arm/aww L. ILLMER, JR.

GAS ENGINE.

APPLICATION FILED APRA, 1907 Patented Nov. 11, 1913.

5 SHEETSWSHEET 3.

W/ TNESSES L. ILLMER, JR. GAS ENGINE.'

APPLICATION IILIID APRA, 1907.

Patented NOV. 11, 1913.

5 SHBETS-SHBET 4.

W/T/VESSES on i 5; miww 1/ h ATTORNEY L. ILLMBR, JR.

GAS ENGNE,

APPLICATION FILED APR.4 1

1,078,286, 907 Patented Nov.11, 1913 5 SHEETS-SHEET 5.

/IO A TTOHNE Y UNITED sTATEs PATENT oEEIcE.

ILLMERJN., or CINCINNATI', oHIo, AssIGNon To ILLMER GAS ENGINE coltrANY, A ConronATIoN OEDELAWARE.

" @celled/tom :it may concern itknownthat I, LoUIs ILLMER, Jr., of the of Cincinnati, county OtHamilton, and State yof Ohio, have invented certain new anduseful Improvements in Gas-Engnes, of 'which'the following '1s a full, clear, 'and' exact specification, such as will enable others skilled in the'art to which it appertains toimake and use the same. ,This inventionrelates particularly to certain improvements in a valve gear for a douyble acting two cycle gas engine, the construction" and organization being such as' will .avoid the` use of cams and admit of positively o rating or forcing the valve 'tqmove in th directions without the use of `closing springs. To this end I employ a' .novel linkage, driven from an eccentric on the crank shaft or other moving parts of the engine, ily-means of which the valves may be opened rapidly and their lmotion .properly accelerated and retarded with respect to the linertia efectsproduced. In this manner I am enabled to produce a valve motion .exactly equivalent to thatof a properly designed rotating cam drive brit withkvout the attendant disadvantages.

In thev operation of valve gears `for gas engines, particularly for engines of high power, it is necessary to take due account of the inertiay and momentum effects produced i bythe valve parts, as otherwise the mechamsm will o rate with'violent knocks and prevent satisfactory operation. It is accerdingly important to open the valve with a ygradually accelerated velocity, and, as the va ve.y nears its open position to retard this velocity, thus starting the valve gradually from. its seat until the highest velocity is attained yand then bringing the valve graduallyxtc restl bythe time it reaches 'its open position. The ysame principle applies upon closing'the valve; that is, the valve should be vallowed to. start rapidly from its open .45 4position but caused to seat gently by gradual retardatiomin order to prevent the knock otherwise,k following the abrupt contact of the valveon its seat. My present invention .is particularly eective in accomplishing this result. Besides dispensing with cams, the mechanism which I 4have devised,xenables me to both positively open and close the inlet valve withjaase and Acertaint vof movement and 5.556, .without opening the va ve against the pres- Specication of Letters Patent.

GAS-ENGINE.

sure of powerful springs which are other- Patented Nov. 1 1, 1913. Application mea Apri14, 1907. sriai No. 366,289.

wise necessary to seat the type of valve to which thls invention particularly relates.-

T he inlet valves of large two cycle gas engines become quite'massive and require very rapid acceleration in order to open and close within the short time allowed for the charging operation of the power cylinder'. Hence the positive or forced closing of the inlet valves forms an important feature of this construction.

My invention involves various other features ofmore or less importance, all of which are fully set forth hereafter.

.In the accompanying drawings, which illustrate one manner in which my invention may be practically embodied: Figure l represents a vertical longitudinal section of the power cylinder of an engine, showing the location of the inlet valves. Fig. 2 is a plan view of one longitudinal half of the engine, particularly illustrating the valve actuating mechanism.y Fig. 3, is a side elevation with parts in section, on the line 3-3- of Fig. 2. Fig. lis an enlarged horizontal section of one of the power cylinders showing the parts adapted for positively actuating the inlet valve in both directions. Fig. 5 is a view of the linkage illustrating its several critical positions by dotted radial lines. Figs. 6, 7 and 8 are elevations of the locking device in its three critical positions.

Each end of the double acting power cylinder carries a puppet inlet valve 28, which valves are annularin form and encircle the pisto-n rod.

Referringparticularly to Fig. 4 which Shows the structure of the valve, it will be noted that the valve has a stem of tubular form, 29, formed integral therewith, and which is adapted to slide in recessed parts of the housing 32. This housing is also provided with a seatbushing 3l, tubular in form and inclosing the tubular valve stem. The bushin is spaced from the stern to form a passage or the working charge into the power cylinder.. For the purpose of cornmunicating motion to the valve 28 the free end of the tubular stem Q9a flanged and adapted to receive 'the two push .rods 89. These rods are of a length r-iciiuient to extend outside of the valve housing parts and are joined hy two sets of straps 92 in order to place the free end of ythe valve rocker'll into operative connection with the valve 28. The rocker 54 carries two arms, so as to straddle the piston rod and is centrally fastened to the rock shaft 55, through which shaft the motion for operating the valve is transmitted.

In the preferred arrangement of the valve mechanism, the puppet valve is positively actuated both in opening and in closing. As shown in Fig. l, the valves 28 may be closed however, by `means of the spring 50. ln that case thevalve rocker 54'niay engage with the inlet flange parts by means of rollers 53 carried by the free ends of the rocker arms and thus operate the tappets 52 which push open the valve and compress the spring 50. A f

The rock shaft 55 extends laterally across the axis of the power cylinder and is mounted in the frame parts of the engine. One of the free ends ofthis shaft extends through its bearings and at its outer end carries a locking device, hereinafter described, which permits the eccentric and a portion of the valve gear mechanism to continue its motion while the puppet valve is permitted to rest on. its seat durlng the considerable portion of the, engine c cle requiring the inlet port to remain close The mechanism for imparting to the shaft 55 its characteristic motion will now be described.

Referring to Figs. 2, 3, 5, 6, 7, and 8 the element 56 designates a reach rod which' is connected in any suitable-manner with the eccentric on the crank shaft or other moving' parts of the engine, giving the reach rod a regular reciprocating motion in synchronsm with the power piston movements. Such an eccentric is diagrammatically illustrated as 88 in Fig. 5. The reach rod 56 is articulated to the driving arm of the wrist plate 57 and said arm is also joined by a parallel rod 58 to the driving arm of a second wrist plate 57a, `identical in structure and function as the first named plate. Each wrist plate oscillates about the wrist pin 59 and they are articulated respectively to the valve devices at the ends of the power cylinder. Each of the wrist plates is provided with a toggle arm 57b which is in turn articulated to the toggle link 60. In the construction shown,V

these links areshapcd to clear the gas and air inlet ducts 33. The other ends of the toggle links 60 are respectively articulated to the link arms 61, which are mounted loosely on the rock shafts 55. Said links 'carry pins 62 projecting laterally therefrom toward the engine cylinder for the purpose of coacting with the hooks 68. These hooks are securely fastenedto and adapted to move with the shaft arms 64 which arms are irn'ilj;v secured respectively to the rock shafts 55,

which shafts, as stated, are in operative connection with the valves 28. The hooks 63 curve upward into an overhanging position with respect to the shaft arms 64. Thearms 64 are also provided with locking toes 63 which are firmly secured to these arms by bolts 63 and adjustable toward andaway from the same by the wedges 63e. The toes 63d are positioned opposite the engaging end or face of the hooks 63 so that the 'pins 62 may just enter between the hooks andthe toes to impart motion from the toggle link-4 age tothe puppet valve in either'direction. The hooks 63 and* the toes 63, which transmit motion from the toggle linkage to the shaft arm 64 are so shaped as to yield slightly when the force is applied to these arts. The valves yare furthermore operated rough the rock shaft-s 55 which also have a slight amount of torsional elasticity, thus the picking up ofthe valve parts is materially eased, especially when, on account of wear, the mechanism may not be in perfect adjust-ment. The yieldingfharacter of these members is however, in no sense commensurate with the large lamount of elasticity of the spring element required for spring closed valves and, in fact, 'performs entirely dissimilar functions. In order to counteract any whipping actionof the reciprocating valve parts that may be occasioned by the limited amount of clasticityjn the rock shaft, the flanged end of the valve, 29, entering the annular recess in the valve housing, may be made to serve' as a dash pot to cushion the valve when Seating.

The mode of action of the locking devices is shown in detail in Figs. 6, 7 and 8 which represent successive critical positions of the head end parts of the gear. The link arm 61 rocks freely on the shaft 55 and causes the pin 62 to move in and out of engagementwith the hook 63 and the toe 63, thus locking the toggle link 60 with the shaft arm 64 and thus causing the toggled eccentric movements v to be imparted to the puppet valves.' It will be observed that the pin 62 does not actually engage with the hook 63 and the toe 63a un-` til the toggle link 60 is raised to its position of alinement with the toggle arm 57" as indi- 'cated' in Fig. 7. At all positions above that of alinement, the locking of the parts 62, 63 and 63d is retained, and the shaft arm 64 is operated by the pin 62. At all positions of the toggle link 6() below the position of alinelnent shown in Fig. 7, the pin 62 is disengaged from the hook 63 and the toe 63, and the link arm 61 moves freely on the rock shaft 55 withoutimparting motion thereto.

The wrist plate 5T under the action of the eccentric driven rods 56 and 58, operates with a rocking or oscillating motion. Through the medium of the toggle link 60, the wrist plate action imparts to the link arm 6l, two oscillations or rocking movements for each complete oscillation or rocking motion of the wrist plate, resulting in the intermittent connection and disconnection of the pin -.tion, reference is, .now had to the ,l fextremapavtionao 4 known. as .posit-ione. i

v-, -.F-ig.i 5.,., showsxthe ilinkge wies redeem onesti-on,

nordsee pose of a detailed explanation of this acy diagram Fig. 5 and-Figs. 6, 7'y and 8.

f the,to

'also indi- `Cates the twoother characteristic positions of thegear by".means of radial center lines,

spends with the eccentric, inner dead center,

.0r-Other extreme position of the toggle arm Y 57". FigSfG, and 8, as noted thereon, cor L,..`respond, respectively with thepositions o, i5

and cof-,Figa 5.4

I Assuming zoV f is to say, the ygle` arm 57".

y responding the parts to he. osi-tion .e

(Figs. 5 ,and 8,) the wrist plate 5"(a is at the eccentric inner dea dcenter position, which lowermost position of the togp The link arm 6l is now like wisepmoved down to its lowermos,l position, whilethe shaft arm 64 and the rocker are in their extreme left-ward positions, the' cor puppet 'valve being closed the pin 62- and the hook 65 and toe ing disengaged. As the wrist plate 57"h reversesitsmovement the parts assume the toggleahnement position bigs. 5 and 7) Which results in the upwa movement oi' @the linkparm lland in the lifting of' the toggle link 60y suliiciently to allor?" the pin y62 `to engage with the toe 63 and the hook 63. Further movement of the toggle causes or lock the shaft arm $64 which in turn, causes the valve to open. The wrist plate 57 then continues its movement until it reaches the eccentric outer deadcenter position a, (Figs. 5 and 6).

vHere it will be seen l that the shaft arm has been locked to the toggle link 60 and moved to a position'to the right of the position l) withgthe result that the shafthas been correspondingly rocked, the valve rocker 54e moved toward the right and the inlet valve lfully opened. The wrist plate then reverses its movement and returns the linkage to the toggle alineznent position b, resulting in the return oit the ' parte 60, 61, 62, 64 and 54 to the position shown in Fig.`V 7 and thus oansing the puppet v.valve'to follow and seat itseljl by reason of the pin 62 actingagainst the toe 'tivelyv opelosing" move The link mechanism continuing its movements under the reverse motion of thewrist plate,

the pin 62is disengaged from its locking devices 63 and 63'@ out the shaft a they valve rocker 54 i l which is the position of v K Y causes the toggle link to Adrop `from the position 2') with the result that the ecoentr'ic .heelal-One @fthe elle` arm i519, to ,b-e

,oscill'atio'ns, y link arm 6l resulting first, in a movement-75 preaches transmitted directlym the valve.'

vwrist plate then continues its movement until the linkage parts return to the position o, the eccentric inner dead center position, and thus completing theoycle of operations ,of the valve gear. During such cycle the wrist 'plate'has' made two movements, or one `complete oscillation while the guide arm has'made four movements or two complete these tour lmovements of the alongside the shaft arm 64 s0 that the locking device may pick up the shaft arm; seco: l, in a movement to the riglhtcarryin the arn'i 64 along and opening t e valve; tird,

inl a movementto the left carrying the arm 80 and allowing the valve to seat; land back ' 1n a movement downward and to 'the i 7ht, disconnecting the locking device to allow a time interval before the return of the arm 61 at the beginning ofthe next 85 cycle of operations. By this means the ec centric may be kept in motion continuously while the puppet valve receives intermittent motion so as to allow the valve .tov re`l main on its seat during approximately threefourths of a revolution of the engine. As the eccentric reaches .the position corresponding to o the toggle link will be movl ing rapidly'in a direction normal ytothe eenter line of the alined toggleJ pins, thus throw' ing the locking element- s 62, 63 and 63d into rapid engagement. At the Sametime the toggle arm 57b and the toggle link 60, being in alinement, the pin 62 will have practically no velo-city component in the direction of the center line of the alined togglepins, vconsequently the motion imparted 4to the inlet valve at this instant causes the valve to open with theV desired gradually accelerated motion. When the wrist plate is moving vapproximately midway between the positions a and b, the valvev willbe traveling with its maximum velocity. Thereafter thel valve velocity is radualiyretarded, due to the fact that t e. eccentric approaches its outer dead center position, which bringsthe valve gradually to rest as it reaches ,its open position. Upon the return of the wrist plate and the other before described operations incident thereto, the 'same effects are produced in the'reverse direction and as the toggle joint again. ap-

its alinement position, the valve is gradually brought to rest and properly seated.

vIt will be observed that while the linkage moves from position or to position. I), the shaft arm 64 is positively actuated through the medium of the toe 63d and 'bythe arrangement which I have before described, the positive movement of the arm 64 is then -The inlet is therefore forced shut by the positive action o the toe dpoacting with -thepifn' 62 M 'which moves with the valvegear-linkag. L50.

In` order to exert an initial pressure on the wvalve-Yseatafter the valve has been brought to rest I provide an expansive spring 93 .(Fig. i). This sprin acts between two c relatively slidable mem ers 94 and 95 one of which is pivoted to a stud 96 project- `ing from one arm A54 while the other is pivoted to a stud 97 projecting from the valve housing. In view however,

of the positive nature of the valve driving mechanism, this spring performs no necessary function in closing the valve. The

- spring 93. may, in fact be dispensed with `since the iston compression created in the power cy inder of a two cycle eigine immediately-'upon the -inlet valve osure is p suiiicient to hold the valve on its seat until itis againreopened by the gear.

The engine shown `is intended to operate according to the two stroke cycle and the inletvalves are opened each timethat the exhaust ports are overrun by the piston; the inlet valves may be actuated and so timed by the valve gear. Itis clear however that this gear may be used for other purposes than that shown in the drawings and also that the elements ,57, 60, 61 and 64 ma be .reversed or modified without departing rom the spirit of tlie"invention.

' What I claim is 1. In an` engine valve gear the combination of a puppet valve, a toggle linkage for actuating the valve comprising a pivoted ,toggle arm and a link, means for oscillatingI the toggle linkage, the alined position -of the toggle arm and the link being intermediate the movement of the toggle arm from its mediate the two alined posit-ion to one of its dead center positions and for forcing the valve'shut by the return movement to its alined position.

3. In an engine valve gear the combination of a puppet valve, a toggle linkage for actuating the valve comprising a pivoted toggle arm and a link, means for oscillating the toggle linkage, the alined position of the toggle arm with the toggle link being interdead center positions of the toggle arm, means for forcing the valve open by the movementof the toggle arm from its alined position to one of its dead center positions and for forcing the valve shut by the return movement to its alined posit-ion, and

iii-fesait; maintaining the valve on its seat during the movement of the toggle arm to and from its opposite dead center position.

4. In an engine valve gear the combination of a pup t valve surrounding the piston rod, a roc shaft in o erative connection with the valve, a toggle inkage for actuating the rock shaft comprising-a pivoted toggle arm and a link, means for oscillating the toggle linkage y toggle arm and the link being intermediate the two dead center positions of the tog le arm, means for forcing the valve open y the movement of the toggle arm from its alined position to one of its dead center positions and for forcing the valve shut by the return movement to its alined position and means maintaining the valve on its seat during the movement of the toggle arm to and from its opposite` dead center position.

5. In an engine valve gear the combination of a puppet valve, a rock shaft, a valve rocker fixed to the rock shaft and in operative connection with the valve, a shaft arm fixed to the rock shaft, a toggle linkage comprising a. pivoted toggle arm and a link, a

Vlink arm loosely mounted on the rock shaft and articulated tothe free end of the toggle link, means for oscillating the toggle arm,

the alined position of thei the alined position of the arm and link being intermediate the two dead center positions of the toggle arm, means locking the shaft arm to the link arm whereby to force open the valve by the movement of the toggle arm from its alined position to one o f its dead center positions and to -'force the valve shut by the return to its alined position, and p.

means for disengaging the locking device during the movement of the toggle arm to and from its opposite dead center positions.

6. In an engine valve gear the combina-V tion of a puppet valve, a rock shaft ,in operative connection with said valve, a toggle means actuating the rock shaft to force the action of the valve in both directions and means for automatically locking the toggle means when it assumesits alined position and maintaining said locked position during the travel of the toggle from the alined position to and from one of its dead center positions and breaking said locked position during the travel of the toggle. from alined position to` and from the opposite dead center position. l

7 In an engine valve gear the combination ofa puppet valve, a rock shaft in operative connection with the valve, a shaft arm fixed to the rock shaft, a toggle linkage forv .actuating the shaft arm, comprising a pivoted toggle arm and a. link, a link arm loose on the rock shaft andarticulated to the free end of the link, and means locking the free end of the toggle link directly to the shaft arm at predetermined periods of the gear cycle. A

. 8. In an engine valve gear the combinationof a puppet valve havinga tubular stem surrounding the piston rod, a flange formed integral with the stem, a set of push rods engaging with the ange, a rock shaft, a valve rocker fixed to the rock shaft, a set of straps connecting the push rods to the valve rocker, a tog le linkage means for oscillating the rock saft whereb the valve is intermittently forced in both its opening and closing movements.

9. In an engine valve gear the combination of a puppet valve, a toggle linkage for actuating the valve comprising a pivoted toggle arm and a link, a link arm articulated to the free end of the link, means for oscillating the toggle link arm whereby the link arm is made to assume its extreme posiv tion in one direction upon alinement of the toggle arm and the hnk, said toggle arm belng movable to each side of the alined position whereby one complete oscillation of the toggle arm imparts two such oscillations to the link arm, means for forcing the valve open and shut during the firs't oscillation of the link arm and means maintaining the valve on its seat during the second oscillation of the link arm.'

10. In an engine valve gear, the combination of a puppet valve, a rock shaft, a valve rocker fixed to the rock shaft and in operative connection with the valve, a. shaft arm also fastened to the rock shaft but spaced from the valve rocker, a, toggle linkage for actuating the shaft arm comprisin a pivoted toggle arm and a link, means or oscillating the toggle arm, the shaft arm being made to assume its extreme osition in one direction upon alinement or ead center position of the toggle and the link, and said link being movable to 'each side of said alined pos1tion, whereby one complete oscillation of the toggle arm Aimparts two such oscillations to the shaft arm, means forcing the valve open durin oscillation of the sha t arm and forcing the valve shut during the second half of said oscillation, and means maintaining the valve on its seat during the remaining period o'f the gear cycle.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

LOUIS ILLMER, JR. Witnesses:

ISAAC B. OWENs, E. I. MCLAUGHLIN.

the erst ha1f.0f the"

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