US786432A - Valve-gear. - Google Patents

Description

' BEST AVAsLABLE Y PAIElWED4 APR. 4, 1905. W. AR. DOW.

VALVE GEAR, AYPLIOATION ILED HOV. 8F 1904.

I nvenkov ttomegs l -rectionr'if theshift occasioned UNITED YSTATES .essi iv/infinie en@ Patented April 4, 1905.

PATENT OFFICE.

VALVE-GAR.

SPECIFICATION forming part of Letters Patent N o. 786,432, dated April 4, 1905. Appiicaeon and November s, 1904. serai No. 231,934.

To allwhmn :It vnfrzq/ coiifcern:

.Be it known thatl, WILLIAM. ROBERT Dow, a citizen of the United States, residing at `Boulder Creek, in the'county of Santa ruz and State of California, have invented a new `and useful Valve-Gear, of-which the follow- 'lngris aspecgiiication. his invention relates to valve-Gears particularly adapted for actuating the slide-valve xo Iof a locomotive-cylinder, and is designed to insure the proper lead of the' .valve in .ull gearasw'ell as 1n mid-gear. A "Thepresent invention has been especiallyT designed to improve the Walsehaert link-motion, wherein the shifting of the fulcrum of the combination-lever in the direction of the movement of the slide-valve to vary the lead o f the valve produces' too great a lead in full gear,'and 'therefore itis an important object .z o of the fpresent. inventi enlto offset the surplus 'Ulead o ,the'jvalve occasioned by shifting the .fulcrum 0f,.the combination-lever by the radius-rod, so as to obtainthe desired increase :n lead in full gear and also obtain the properz 5 lead ,in nud-gear. To Gem lish vthis object, it is lproposed to shift thecrum of the combination-leveratright an les to the diy the radiusL rod in such manner as to decrease the throw 3oA of the combination-lever to a predetermined extent'and .tocounteract or .offset the usual increase in lead occasioned by the shifting of the fulcrum of the combination-lever in the -direction .of the movement of theslide-valve.

With these and other objects in view the present invention .consists in the combination and arrangement of parts, as will be hereinafter more fully described, shown in the accompanying drawings, and particu- 4o larly pointed out in the appended claims, it being understood that changes in the form, .pro ortion, size, and minordetails ma f be ma e within the scope of the claims wit out departing from 'the spirit or sacriicing any of .45 the advantages of the invention.

In thel accompanying drawings, Figure 1 is a side elevation of the Walschaert link-niotion having the improvements of the prese-nt invention included therein. Fig. 2 is an enlarged detail cross-sectional view on the ime 'parts o 2 2 of Fig. 1. ,'Fiv. 3 is a cross-sectional view on the linel 3 3 o? Fig. 2. Fig. 4 is a detail perspective view of the shiftable cam for shifting the osition ofthe fulerum of the combinationever. Fig. 5 is a detail pers ec- 5f tiveview of the bracket member whici is shifted by the cam. Fig. 6 is a da rammatic view illustrating the )rinciple involved in the present invention.. igs. 7',` 8, and 9 are detail views illustrating different positions of the s'hiftable cam for shifting-the fulcrum of the combination-lever.

Like characters of reference designate corresponding parts in each and every ligure of the`drawings. 65

To illustrate the application and operationA of the resent improvement, theessential the Walschaert link-motion .have

een' shown in the accompanying drawings, wherein 1 designates a piston-rod having a .7o cross-head 2 working between the upper and v lower guide or frame bars 3 and 4. ln-rear of the cross-head is the usual crank-arm 5, Which is driven from the cross-head by the usual connecting-rod 5. The usual slide- 75 valve is shown at 6 and is provided with an ordinary valve rod or stem 7, having its rear end provided with a slide-block 8, working in the channeled upper portion 9 of the bracket 10, su ported upon the top of the upper 8o yframear 3 in substantially "the usual manner. Thecombination-lever11 has'its upper end pi'votally connected to the slide 8 by a; pin 12, projected laterally from .the-slide, while the lower end of this lever is operativelyconnected to the cross-head 2b" a pendent arm 13, rigid with the cross-head and a link 14, pivot-ally vconnected at its opposite ends to the lower ends ofv the arm 13 andthe combination-lever,respectively. ln rear of co the combination-lever is the usual upstand-A ing link 15, having an intermediate fixed pivot 16, carried by a bearingor bracket 17, which is in turn supported upon a standard 18, rising from the combined frame and guide 95 bars 3 and 4. Thisl link carries the -usual saddle-block 19, to which is connected the radius-rod 2), the forward end of the latter being connedted to the combination-lever in accordance with the present invention, as roo cato'ry movementto the slidev'al-ve 6r In' 2o, ,which neon-neared to thefuiemm 27; @di also ifothe-llink l'zby means iofthe saddle- Abloc 1- link will impartanendwisemovementtotheVV fss ' the upper end .ther'eot and extending into thel i that ofthe ordinary Walschaertlinliemotion creusirg'; the lead ingfull earproduces a i longer. e

crnni- 27'bysl1ifting the-latter .vertically or at f rightanglesV to; the movement-:Lof said ful-1 crum.; .'llo obtain this featureythe :fulcrurn combinationelever,1-1' iS provided with a lonv.

gitndinal slot ,28 tf, receive the fulcrum'epin ',-andgpex'init ofk theglatterbeing slid therein.

works in the', s lot of' 1the combination-lever,

will. be hereinafter described. lforrockin-g the link 15 there is lthe usual eccentric rod 21. The saddle-block 19 lisishifted uponithelinl 15 in the usual mannerjby the tumbling-shaft 22, which carries a crankfarm 237 there being a link 24 (shownin dotted linesin Fig. 1) extending between the crankarm-23 andthe saddle-block, and the tumbling-shaft'is con trolled in tlieusual manner.; by means-` o. the 'j crank-arm 25, risingfroni' theshafd' and the connecting-rod 26, ivotall'y connected to cab of the engine and connected to' the reversing-leverin the usual manner'. I

As tl1i1`s'ffar'l describedf'the 'con struction is;

and operates as follows 'lhe- -corribination-le`-` ver '1-1 isfswung u on-Litsffulcrum 27 throufrhv its connection'wit .theTc'ross-head of the pis'- ton-rod, so as fto impart'fthedesired recipr`o.

addition to'its swinging-movement the' com bination-leverV also has' -a'r bodily. movement occasioned by 'the -shiftingfoffthel ulcruln 27 in the direction of the movementof the valve by the y endwisef'mvement of. the radiusrod 5 ositioni 'midway b etween.- the end ofthe here will be no .end-WSYGf'movex/'ient adi'Is-'rod `2O. "Hence theffulcr'u'm vv271` will"jreriiainl .stationary in midgearg'. Upon shifting the-'saddle-block .to-eitherjside of. tlie center ofthe link lffor -increased'lspeed said radius-rod 20,'-land therefore 'thefulcrum 2 7 will-.be-recipr'ocated intlfie direction ofthe" :moven'xentl ofthe ,.-val've' 6 fsimultaneousl nwith Ithe., 'swinging movement of the 'comb1"f nationflever.' 1 1 wherefore tlie :bodily movel' nientfimpaxted to" .the leven is also imparted to .theslide-valve-G gin- 'additionto the movement occasioned byrthe' swingingof the lever,-

inent'-, fortthevalve, which incr( thereof.' To .have the'properi gear, the, Walschaert- 'arrangement `f`for i117` I,adfthan is'l essentie vfor' the `best 1resultsfnn'd r` tn ,overcoinethis objection I pro-.f 'pose'` to reduccion 4neutralize .the .increased eadoccasion'ed Aby tlie. n1ovement of the -ful- 27 .isj'orined inf the. nature of ya" pin' and the Airantifrictionqi'oller 'or sleeve 29 is carried by that portion of the` fulcrulnLpin 27 .which pedane slot or opening 31 to 'receive the'fcrward end ofthe radius-rod20, which is pierced by the fulcrum27, so 'as to be pivotally connected therewith. The upperendof'the link 3U is tially Leshape bracket 32, the substantially horizontal arm 33 ,of which loosely pierces the link-to. pivotally connect the latter there- 1to,while the 11 pright arm or. member 340i the bracket works vertically, .in .auideway 35, formed inthe upper portion o the stationary 'brackety 10 and in rear lof the valve-slide 8. In rear of the lmovable bracket Vthe stationary bracket is provided with' a substan- A vtially horizontal open-ended gnidewa'y'for the reception of a, shiftable cam-block 37,

4which is providedwith a substantially 'V- 'Epiv'otally hun .from an inver-ted snbstanshaped slot 38,. in'which is received apm or pro'ection-SQ, carried bythe upright arm 54 of t e movable bracket and provided with an' anti fricthm-sleeve 40. A rod 41 is pivotally connected to the rear end of the slidable cam 37 and has itsrea1 'end pivotally'connectedto the 'crank` 250i the -tumbling-shatt 22, as at .242, whereby the cam v37 is 'simultaneousl p l l*shifted with'the shifting of the 'saddlehbl'oc -xlf the .saddle-block 19beshifted" V19 upon' the'link 15.- YVhen in mid-gear, as shown in Fig. 7, vthe pin or projection 39 of vthe movablebracket 32 is at the bottom of .quently the lowermost position of thefulerum 27l at the lowerje'nd of the slot 28 of the com- .binationelever 11. 1 .Upon moving the revers# 'ing-lever ahead the shiftablecam 37 will be moved in the direction of the arrow on 7g :o5

vthe-slot'38 'in tlievcan-block 37',"Which is the lowermost position 'ofthe in 39,` and consewhereb'yfthe pin `39 will be moved vertically bythe ,rear portionof the lower wall ofthe v slot 538 until -itreaches its highest position at the 'rear en d of the'slot.

crum27 will also be moved upwar that this upward shiftingvof the fulcrum 27y does not interfere 4 with its reci rocatory movement .under the influence of t 'e radius- .rod 20,'o1 the reason lthat the link 3() is ipivi 'ot-ally hung from the movable bracket'BZ;v

and therefore permits ofthe necessary recip,n

rocation of 'the fulc'riiIn-Z''. llVhen thelever -is reversed, .thesh'iftalble cam 37 is of course moved in the oppositedirectiomas indicated' 4 bv the-arrow in'Fig4 9; thereby drawing the pinB-Qto the bottom 'of' the slot 38 and then 2,5 l:

As thel "in'39 ieV moved lupwardly the bracket 32 an the link 301willibe moved therewith, whereb the `ful' (ily in the l slot 28, which decreases the'thro'w ofthe com-" binationleve'r. lt will here be explained IIO elevatingl the pin inthe forward portion of the slot as the llever passes rearwardly beyond mid-'geartlie fulcrum -27 of course folowing the movement of the pin 39.

j In explanation of the result attained lby 13a I shifting the fulcrum of the combination-lever at substantially right angles to the direction of its reciprocating movement reference will be had to Fig. 6 of the drawings, wherein it will be assumed that theradius-rod 20 is at the center of the link l5, in which position there will be no reciprocation ofthe f ulcrum 27, and thereforethe movement of the valve will be determined by the extreme ositions a and a of the upper end ofthe com inationlever 11, as indicated by the full-line position thereof. When the radius-rod'ZO is shiftedl to either side of the center. of the linkf15, an endwise movement will be imparted to the radius-rod and the fulcrum 27 will be in turn reciprocated-4say, Vfor instance," fromv the point 27b to the point 27'-the movement of the valve then correspondin@r to the distance between the positions b and b of theupper end ofV 'the combination-lever.` The movement 'ofthe valventhrough the distance b b produces :ltoo4 great* a lead of ythe `-valve but this-is offset by thejshiftingyo the .cam 37,.

which elevates the fulcrum 27 from the lowermost-end Fof the -V-shaped slot in the cam,

vand-While theslidablermovement of the fulcrumv is thesame as before', as indicated at 27c and 27',*the fulcru'mQ- pin having be'eni shifted-upwardly thIOU gh the slot in the combinationleverV the vthrow of the lever has been -proportionately reduced,Y as indicated by the points' c and c', thereby reducing4 the movement of the valveand vproducing the most'eliective lead thereof.

From the fore oing description it Will be understood that t e a plication of the present invention to the Wa schaert `gear does not change the .principle and operation of the: latter 1n any manner whatsoever, as the swinglng link 30 permits of the usual reciprocation of the fulcrum of thecombination-lever; butthe fulcrum of the combination-lever is shifted longitudinally upon the lever to increase and decrease the throw thereof. in such a manner as to neutralize the excess movement of the valve occasioned by the reciprocation of the fulcrum.4 Moreover, the cam 37 is normally stationary and may be connected directly to the tumblinG-shaft for, simultaneous shifting with the shitting of the Saddle-block to shift* the radius-rod. f

Havin fully described the.invention,what is claimetgl isv 1.,In a valve-gear, the combinationl of a slide-valve and its rod, a iston-rod, a lever connected at opposite en s to the'valve-rod and the piston-rod and having an intermediate movable fulcrum,a radius-'rodeonnected to the fulcrum for moving the same, and means to reduce the increased movementof the valve occasioned b v the movement of the fulcrum in changing from mid-gear toward full gear.

2. In a valve-gear,/the combination of a slide-valve and its rod, a piston-roda lever shift the fu BEST AVAlLABLE 00F" 3 connected at opposite ends tot-he valve-rod and the piston-rod and having an intermediate movableufulc'rum, a radiuswrod connected to the fulcrum for moving the same, and

.means to shift the Jr'ulcrum longitudinally of the lever.

- 3. I na valve-gear, the combination of slide-valve and its rod, 'a piston-rod, a lever c'onnected at opposite ends to the valve-rod and the piston-rod, an intermediate fulcru 1n for the lever, means to reciprocate the fulcrum and means to shift the fulcrum in the 5l AC valve-gear having a lever, means to,

bodily reciprocate the lever in the direct-ion of its swin ing movements, and means to icrum of the lever longitudinally vof the latter.

y6.| A 'valve-gear having a lever provided? 'slide-valve and its rod, a. iston-rod, a lever connected at opposite en s to the. valve-rod and the piston-rod and provided with an intermediate longitudinal slot, a fulcrum located in the slot, means to shift the fulcrum longitudinally ofthe slot, and means to reciprocate the fulcrum transversely of its shiftable movement.

8.' In a valve-gcar, the combination of a slide-valve and its rod` a. iston-rod, a lever Aconnected at oppositeen s to the valve-rod and the piston-rod, an intermediate fulcrum for the lever, a cam to shift the fulcrum in. the longitudinal direction of the lever, and meansto reci 'rocate the fulcrum transversely of its shiftab e movement. I

9. In'a valve-gear, the combination of a slide-valve and its rod, a pistonrod, a com-Y bination-lever connected at opposite. ends to 'the valve-rod and the piston-rod, an intermediate ulcrum for the Vcombination-lever, means for reciprocating the tule-rum in the direction of movement of the valve, and means -for shifting the fulcrum longitudinally of the combination-lever.

10. In a valve-gear, the.combination oi :1. slide-valve and its rod, a piston-rod` a coinbination-lever connected at opposite endsl to the valve-rod and the piston-rod, an inicimediate fulerum for the combination-lever. a link fulcruined intermedizm olt its ends. nn

eccentric rod connected to the link, a radius-- rod extending between tlux link und 1lu l'ul- Crum. of the combilmtiolnlewr, and means to shift tlu` l'ulruin longitudinnliv ol' llucoinbinziti(mlevor.

l1. ln :1 valve-gear, ille combination oi :1 slide-valve und its rod, u piston-rod, n com vos IIC

IBS

ISO

Y, billalgionle'ver eenneetedelseppeste ends te braekel; lievi means to f'shl ftA4 A(alle moyzgllfnlel bracket and -el'ideqalyefd ips red, e pistn-rod; 421.00111-- bmeiglon-lever'enneeiied et 'oppositefende to thevelverod andthe' pistoni-red, afulerum thereon, 4e swingig link suppertingthe fulav'lngjen'neljned nslet, 4file- 1.11livable breeket avmgla, poj ctiehnenterjggthe slotl to -m'ove y connected to @he pre eetegl .pofrton of thefulsa s1ideve1velndisljodj@ 'piston-roma, eemblnetlon-levelf connected-VatiOppem-te ends lio endpgojeeted 'at l BEST AVAMBLE cee-f the bracketend 'e'onneeed te the fulemm of thelevezto' support the same 15o-move the breeketge euml) shalt, means rod.

.a slide-valve end its rod find e peton'jfod, olfy yaJ statlona'ry"bracket halvmg epalrjef guider' ways 'extending in' `tl1e 'direeten. of nieveeatedbetween endet'Substehtelly xiighlzerlf g'les "1101 the .first mentioned v@fulfileyyfays; ef bl'aeketmovable longitudinally. in :the letter] movable braeketfe eenl binatiofleyep eon-

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