US2553860A - Means for automatically adjusting the stroke of locomotive piston valves - Google Patents

Description

May 22, 1951 J. F. MCQUILKIN MEANS FOR AUTOMATICALLY ADJUSTING THE STROKE 0F LOCOMOTIVE PISTON VALVES 5 Sheets-Sheet 1 Filed March 1, 1948 J. F. M QUILKIN MEANS FOR AUTOMATICALLY ADJUSTING THE STROKE 0F LOCOMOTIVE PISTON VALVES May 22, 1951 v 3 Sheets-Sheet 2 Filed March 1, 1948 A INVENTOR. JAMES [VI/ Qua ff/N- ATTOR/WEY.

May 22,} 1951 J. F. MCQUILKIN 2,553,360

I MEANS FOR AUTOMATICALLY ADJUSTING THE STROKE 0F LOCOMOTIVE PISTON VALVES Ema March 1, 1948 s Sheets-Sheet s 52 6;? a.? 4 2/ If Q INVENTOR.

AT TORNE Y.

iatenteel lVlay 22,

FFICE MEANS FOR AUTOMATICALLY ADJUSTING THE STROKE OF VALVES LOCOMOTIVE PISTON James 'F. MQuilkin, Laramie, Wyo.

Application March 1, 1948; Serial No. 12,371

12 Cliiiii.

This invention relates toa valve gear media;- smrf to e at n the cy inder sl d lve fl locomotives and has for its principal object the provision of a simple, positive and highly .effii t de fo ope at neth slide a ves. of ii locomotive, which will eliminate the multitude Qi QYePsJ n S a d r k at .iilt m ed iq t is urpos a which i pr v q m: plete and positive control of the valves at all Anothe bje q t wi en ui qpmy de automatic means for oontrqlling the setting of the valves in oonsequence of variat ions in back pressure in the oylinders so that the most efficient setting will be automatically obtained at i m H -Qihe -bieiee d ed ent e' mr side th s e ili r eti e 9 e e eiii u eli is i eed seesaw e aa q n i' i y- These will become more aiiiaarer it from the foltime Q i'lpti P-l i. Il h p lewine de i fi d riptih iith leveeien eeiere q .is a nte th e m iv qmwhswhhhiorms? e earth 695-, Li emfh meml .vrie fiq i se P rts all views of the firewing and throughout the description.

the armies; Fig. l is a smile elevation of s xie i iinsie eeeism s rat n its r e i6 theedj aent jaartsoi a tvpioallocohiotive W f e is pl nv i heimp d valv .12m:- a mechani ms i flll i li a tn i w R tions of a loooinotive are outlineil' diaraliiiiiatical'lyi Fig. 3 is an enlarged sigle view of an operating erase and its assoei'ated meehanisni whi'h is einpl'avea in the present inveiition; I

Fig; '4 a longitudinal se'o'tioli thrzsugih the stair fiiiiamsrfi taken on the line n+4, Fig-1 3'; 4

Fi 6' i emerged de' :11 view g' aiij of valve operating levers eniblovetl in th'invehti'oii, the; View Being" taken onth imet g. 2;

v Figi'f emer es three diagraihs'showlfi ib'alfiiirati'ri'g positions of the" levers of Fig. 8'; anEl F'. a" is" a eros's 'sctidn' taken 611 the) line '8-8,

A A v ii, the arawins, typical elin entspf a, motive are aiagismmaueany iit'lind' aria ignated by reference numerals as follows: Pow r' eynndl' It; drivlh'gefoss'heau' 'il it; drive wheels 13; drivewliehaile' boxes I sl iii e valve roii's'iifij valve I guia'es l1"; vawecress' Head's" l8} ahd lofi frariienie'iiibers [9. k

p lot wheels of outer shaft seats sad afi" iiinei 'solid' l d, i s ab iqu e l. 0.2% v. o i, me s. ?9 iwmi j i iemv eihsi es were .he s a l eve was driven in any suitable :"Aanner so as to rptate in thesarne direction and at the same speed as the o s .9 .methed eifl iii e iheekeve 291;) 1 s: rei uinfi s 1 -ed 2 a om ri e a bevlfldrlve see? 2.3 ee. s 1 t e axe. e; we i 'v gear 28, Inounted. on the shaft sleeve 20. A tele seeping shaft e is two bevel gears 26, one meshing with the gear 23 aria one with the gear The shaft 25 is sui bor't'd ii'l two yoke's 2? one irfountil on the afiil'e" I' l aha one on the sh ft' slev 2D. 7 I I A Eira'fili" druifi Z'jilis 'fiidly mounted oneaoh iitf'eiiiity oi" the some shaft 2 a. The crank drums are bvlfii'tirial ans provided with open oute'r i de was ze'e xte d diametrp "sf ea'oh fcirum 28' in parallel relation, The drums 28 are sifiiilai". Iii each a Crank block 3!] is slidably mounted onthe rods 29 so that it may move therealong, A counterweight 3! is sifiiilaily sliid'ahl'v iiioiiteelupoii the v rods 29. The train; block 3'13 and trie csumerweigm 31' are aus'il to have towards and away rom each otheriii ur'fis'oh m als ofa right and left l1" Id threaded 5561: s aft s2 'wh'iol'i isth'rea'ded through I it. is? .i i

the hack an and the oiinte rweight 3 l.

:ts the jak shaft s2. 7

A main connecting rod 35 extends frolr'n tll' 115151 1 jcfi'a'rik' pill assaua sef'on'd veonriferating rod vertically elongatdj slot "42 in" the lever 3S. 7

gearsfl' and 45 which are rotatably mounted on the dire mierehee of the dru 2s andheld i A friction band 41 surrounds" the rihg g'ar' it,

and a similar friction band 48 surrounds the ring gear 4.5. The friction band 4'! may be contracted to grip the ring gear 44 by means of a plunger terminating in a piston b in a pressure cylinder 5!. A spring 52 acts against the piston 59 to constantly urge the friction band 4! into engagement with the ring gear 44. It can be forced out of engagement by admitting fluid under pressure to the pressure cylinder 5| above the piston 50.

The friction band 48 may be forced into engagement with the ring gear G5 by means of a second plunger 53, terminating in a piston 54 within a second pressure cylinder 55. A spring 55 which acts against the piston 54 to constantly urge the band 38 out of engagement with the ring gear 45 and it may be contracted to the closed position by admitting fluid under pressure below the piston 54 to force it against the action of the spring 55.

The pressure cylinders 5i and 55 are connected by means of back pressure pipes 51 with the exhausts from the valve chambers l5. The usual locomotive has a back pressure pipe leading from the valve chambers to a back pressure guage in the cab. The pipes 57 may be connected directly to this if desired.

The outer shaft sleeve 20 terminates at each of its extremities in a quadrant lug a key 58 having a width of 90 and each crank drum 28 is provided with a similar projecting quadrant lug or key 59 also having a width of 90. The keys are positioned to be contacted by the keys 58 to cause the drums 28 to rotate with the shaft sleeve 28. Since both drums are fixedly mounted on the shaft 2i they will rotate in unison.

Operation Let us assume that the locomotive is moving forwardly. The crank drums 28 are also rotating forwardly with the drive wheels i3 and at the same speed as the latter. The crank pins 33 at the opposite sides of the locomotive are set 90 apart, similarly to the setting of the engine drivers and cross heads H.

Each forward motion of each crank pin 33 forces the upper extremity of the floating lever 38 forwardly. The lower extremity of the lever 33 acts against the pin 4! as a fulcrum, as shown at C in Fig. '7, to force the valve rod [6 forwardly.

Each rearward movement of each crank pin 33 pulls the upper extremity of the lever 38 rearwardly, pressing against the pin 4| as shown at A in Fig. 7, to move the valve rod 16 rearwardly.

The second pin 35 provides automatic lap and lead for the slide valve. It can be seen that whenever the lever 38 swings forwardly, as at C, Fig. 7, the pin 35 will be moving rearwardly. This rearward movement is communicated to the upper extremity of the lever 39, causing it to pivot about the bolt 40 so as to swing the fulcrum pin 4i forwardly to increase the forward motion of the valve. The same action takes place when the pin 35 swings rearwardly to increase the rearward movement of the valve.

The length of the stroke of the valve can be varied by moving the main crank pin 33 toward or away from the axis of the shaft 2|. This can, of course, be accomplished by rotating the jack screw 32 in one direction or the other. This adjustment must be made while the drums 28 are in motion, and is accomplished through the medium of the ring gears 44 and 45 and their friction bands 4? and 48.

For instance, if in Fig. 4 the band 41 is brought into contact with the ring gear 44, it will tend to resist rotation of the latter, causing the gears 43 to travel along the teeth of the gear 44 and impart rotation to the jack shaft 32 causing it to thread itself into both the crank block 30 and the counterweight 31, so as to move them toward the axis of the shaft 2|.

If the band 47 is released and the band 48 tightened, the gears 43 will travel in the other direction along the teeth of the retarded ring gear 45, rotating the shaft 32 in the other direction to separate the crank block 39 and the counter-weight 3|. Thus, any desired degree of eccentricity for the crank pin 33 can be obtained by manipulation of the frictional engagement of the band 41 and 4B.

This manipulation is automatically accomplished from the pressure in the black pressure pipe 51. Should the black pressure in the cylinders increase, it will flow into the pressure cylinders 55, clamping the friction bands t3, and will flow into the pressure cylinders 5i, releasing the friction bands 41, causing the jack shaft to shorten the crank stroke and shorten the valve stroke. Should the back pressure fall below a minimum determined by the springs 52, the lat ter springs will apply the band 4? and the spring 55 will release the band 43 to bring the back pressure to the desired minimum.

It will be noted that the stroke of the second crank pin 35 increases as the stroke of the main crank pin 33 decreases. Therefore, the lap and lead of the valve will be controlled in inverse ratio to the stroke thereof, which, of course, is the desirable condition.

In order to reverse the locomotive, it is necessary that the crank pins 33 and 35 be rotated This may be accomplished in any desired manner. One method of accomplishing it is to provide gear teeth 68 on the drums 28 with which toothed rack bars 6| may be brought into engagement. The rack barsGi extend to any desired operating mechanism in the cab of the locomotive, by means of which they may be lowered into engagement with the teeth 5B and forced forwardly sumciently to rotate the drums 28 and their connecting shaft 2i forwardly 180. The racks are then lifted from engagement with the teeth 60.

The drums are free to rotate forwardly, since the keys 58 thereon simply move away from the keys 59 on the shaft sleeve 20 to the broken line position in Fig. 5. This places the keys 58 on the opposite side of the keys 59 so that as the latter move in the reverse direction, they,will again contact the keys 58 and rotate the drums in the reverse direction.

While a specific form of the improvement has been described and illustrated herein, it is desired to be understood that the same may be varied, within the scope of the appended claims, without departing from the spirit of the invention.

Having thus described the invention, what is claimed and desired secured by Letters Patent 1. A valve gear for operating the slide valve rods of a locomotive having a drive wheel axle comprising: a shaft extending transversally of said locomotive; means for driving said shaft from said axle; a first eccentric crank pin at each extremity of said shaft; means for varying the distance between the axis of said crank pins and the axis of said shaft;' a crank arm fixed to and extending from each of said crank pins diametrically across the axis of said shaft; a second crank pin mounted on the extremity of each of said crank arms; a first connectingrod extending from each of the first eccentric crank pins; asecond connecting rod extending from each of the second crank pins; a floating lever pivoted intermediate itsextremities on each of said valve rods, said first connect-ing rods connecting with the upper extremities of said floatin levers; a swinging lever pivoted adjacent to each of said floating levers; said second connect ing rods being connected to'the' upper extremities of said swin ing levers; and means hingedly connecting the lower extremities of said floating levers to said swinging levers; v

2. A valve gear for operating the slide valve rods of a locomotive having a drive wheelaxle comprising: a shaft extending transversally of said locomotive; means for driving said shaft from said axle; a crank drum at each extremity of said shaft; a first crank pin supported from each drum; a crank arm' fixed to and extending from each of said crank" pins diametrically across the axis of said shaft; av second crank pin mounted on the extremity of each of said crank arms; a first connecting rod extending from each f the first crank pins; a second connecting r'od extending from each of the second crank pins; a floating lever pivoted intermediate its extremities on each of said valve rods, said first connectin rods connecting with the upper extremities of said floating levers; a swinging lever pivoted adjacent to each of said floating levers, said second connecting rods being connected to the upper extremities of said swinging levers; means hingedly connecting the lower ex"- tremities of said floating levers to said swing ing levers; and means for simultaneously moving both crank pins diametrically of each drum to vary the stroke of said pins. 7

3. A valve gear for operating the slide valve rods of a locomotive having a drive wheel axle comprising: a rotatable shaft journalled on said locomotive and" extending parallel to. said axle; a crank drum secured on each extremity of said shaft; a crank block slidably mounted in, each crank drum so as to move diametrically thereof a crank pin projecting from each crank block; means connecting each crank pin with one of the valve rods'of said locomotive; and means for rotating said shaft from said axle.

4. A valve gear for" operating the slide valve rod of a locomotive having a drive wheel axle comprising: a rotatable shaft journalled' on said locomotive and" extending parallel to said, axle; a crank drum secured on the extremity of said shaft; a crank block slidably mounted in said crank drum so' as to move diametrically thereof; a crank pin projecting from said crank block; a jack screw extending across said drum and being threaded; through saide crank block; means for rotating said jack screw to vary the eccentric position" of said block; means connectir'igsaid crank pin with the valve rod of'thelocomotive; and means; for? rotating. said shaftfrom said axle.

5. A valve gear for operating the slide valve rods of a locomotive having; a drive wheel axle comprising: arotatable shaft journallecl on said locomotive and extending; parallel to said-a axle};

a crank drum secured on each extremity; of said shaft; a crank block slidably mounted in each a jack screw extendin across each drum and being threaded through the crank block therein; a driven gear on the extremity of each of said jack screws; two ring gears surrounding each crank drum in mesh with the opposite sidesof the driven gear therein; means for retarding rotation of either of the two ring gears on a drum so as to impart rotation to said driven gear to cause the jack screw of that drum to vary the position of the crank pin therein; means extending from each crank pin to a connection with a valve rod of the locomotive; and means for driving said shaft from said axle.

6-. A valve gear for operating the slide valve rodsof a locomotive having a drive wheel axle comprising: arotatable shaft journalled on said locomotive and extending parallel to said axle; a crank drum secured on each extremity of said shaft; a crank block slidably mounted in each crank drum so as to move diametrically thereof; a crank pin projecting from each crank block; a jack screw extending across each drum and being threaded through the crank block therein;- a driven gear on the extremity of each of said jack screws; two ring gears surrounding each crank drum in mesh with the opposite sides of the driven gear therein; an independent friction device for each ring gear positioned to contact the latter; a pressure responsive device mounted to bring one of said friction devices: into contact with one of said ring gears; a second pressure responsive device arranged to force the second friction device out of contact with the second ring gear; spring means for moving said friction devices opposite to the movement of said pressure responsive devices; a conduit connecting said pressure responsive devices with the exhaust of said locomotive; means connecting. each crank pin with a valve rod of said locomotive; and means for rotating said shaft from said axle.

7.- Means-for reciprocating the valve. cross head of a locomotive comprising: a floating lever passing through said cross head and extending above and below the latter; a swinging lever pivoted alongside said floating lever and extending above and below the pivot thereof; hinge means connecting the lower extremity of said swinging lever to the lower extremity of said heating lever; an actuating shaft; a first eccentric crank pin carried by said shaft to one side of its axis; a second eccentric crank pin carried by said shaft to theopposite side of its axis; a first connecting rod extending rearwardly from the upper extremity of said floating lever to. said first crank pin; a second. connecting rod extending rearwardly from the upper extremity of each swin' ing lever to said second crank pin so that said connecting rodswill be moved in opposite directions due. to the opposite eccentricity of said crank pins; and means for rotating Said actuating shaft in consequence of themovementof said locomotive;

8; Means for reciprocating the valve cross heads of a locomotive comprising: a floating lever passing through each cross head and extending above and below the latter; a swinging lever' pivoted alongside each floating lever and extending above and below its pivot; hinge means connecting the lower extremity of said swinging lever to the lower extremity of said floating lever; a-first connecting rod extending rearwardly from the upper extremity of each floating lever; a second connecting rod extending rearwardly from the upper extremity of each swinging lever; a valve shaft extending across said locomotive i'earwardly of said connecting rods; a crank drum on each extremity of said shaft; a crank block positioned to move diametrically of each crank drum; a first crank pin extending outwardly from each of said crank blocks upon which the rear extremities of the first connecting rods are mounted; a crank arm fixed to and extending diametrically from each of said crank pins to a position on the opposite side of the axis of said shaft; a second crank pin mounted on the extremity of each crank arm upon which the rear extremities of said second connecting rods are mounted; and means for rotating said shaft in consequence of the movement of said locomotive.

9. Means for reciprocating the valve cross heads of a locomotive comprising: a floating lever passing through each cross head and extending above and below the latter; a swinging lever pivoted alongside each floating lever and extending above and below its pivot; hinge means connecting the lower extremity of said swinging lever to the lower extremity of said floating lever; a first connecting rod extending rearwardly from the upper extremity of each floating lever; a second connecting rod extending rearwardly from the upper extremity of each swinging lever; a valve shaft extending across said locomotive rearwardly of said connecting rods; a crank drum on each extremity of said'shaft; a crank block positioned to move diametrically of each crank drum; a first crank pin extending outwardly from each of said crank blocks upon which the rear extremities of the first connecting rods are mounted; a crank arm fixed to and extending diametrically from each of said crank pins to a position on the opposite side of the axis of said shaft; a second crank pin mounted on the extremity of each crank arm upon which the rear extremities of said second connecting rods are mounted; means for rotating said shaft in consequence of the movement of said locomotive; a diametrically extending jack screw rotatably mounted in each crank drum and being threaded through the crank blocks therein; and means for rotating said jack screws while said crank drums are rotating for varying the radial positions of said crank pins.

10. Means for reciprocating the valve cross heads of a, locomotive comprising: a floating lever passing through each cross head and extending above and below the latter; a swinging lever pivoted alongside each floating lever and extending above and below its pivot; hinge means connecting the lower extremity of said swinging lever vto the lower extremity of said floating lever; a

first connecting rod extending rearwardly from :the upper extremity of each floating lever; a :second connecting rod extending rearwardly from the upper extremit of each swinging lever; a valve shaft extending across said locomotive rearwardly of said connecting rods; a crank drum on each extremity of said shaft; a crank block positioned to move diametrically of each crank drum; a first crank pin extending outwardlyfrom each of said crank blocks upon which the rear extremities of the first connecting rods are mounted; a crank arm fixed to and extending diametrically from each of said crank pins to a position on the opposite side of the axis of said shaft; a second crank pin mounted on the extremity of each crank arm upon which the rear extremities of said second connecting rods are mounted; means for rotating said shaft in consequence of the movement of said locomotive; a diametrically extending jack screw rotatably mounted in each crank drum and being threaded through the crank blocks therein; means for rotating said jack screws while said crank drums are rotating for varying the radial positions of said crank pins; said latter means for rotating being operable by and in consequence of variations of the pressure of the exhaust steam of said locomotive.

11. Means for reciprocating the valve cross heads of a locomotive comprising: a floating lever passing through each cross head and extending above and below the latter; a swinging lever pivoted intermediate its extremities alongside each floating lever; hinge means connecting the lower extremity of said swinging lever to the lower extremity of said floating lever; a first connecting rod extending rearwardly from the upper extremity of each floating lever; a second connecting rod extending rearwardly from the upper extremity of each swinging lever; a valve shaft extending across and terminating at each side of said locomotive rearwardly of said connecting rods; a pair of fixedly-spaced, eccentrically-positioned crank pins carried at each extremity of said shaft, the pins of each pair being positioned on opposite sides of the axis of said shaft, the first and second connecting rods at each side of said locomotive being respectively connected to the two pins of the pair of pins at that side; and means for rotating said shaft in consequence of the movement of said locomotive.

12. Means for reciprocating the valve cross heads of a locomotive comprising: a floating lever passing through each cross head and extending above and below the latter; a swinging lever pivoted intermediate its extremities alongside each floating lever; hinge means connecting the lower extremity of said swinging lever to the lower extremity of said floating lever; a first connecting rod extending rearwardly from the upper extremity of each floating lever; a second connecting rod extending rearwardly from the upper extremity of each swinging lever; a valve shaft extending across and terminating at each side of said locomotive rearwardly of said connecting rods; a pair of fixedly-spaced, eccentrically-positioned crank pins carried at each extremity of said shaft, the pins of each pair being positioned on opposite sides of the axis of said shaft, the first and second connecting rods at each side of said locomotive being respectively connected to the two pins of the pair of pins at that side; means for rotating said shaft in consequence of the movement of said locomotive; and means for moving the pairs of pins diametrically of the axis of said shaft by, and in consequence of variations of, the pressure of the exhaust steam of said locomotive.

JAMES F. MCQUILKIN.

REFERENCES CITED The following references are of record in the

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