US2527637A - Ballast removing machine - Google Patents

Description

1950 R. s. KNIFFEN ET AL 2,527,637

BALLAST REMOVING MACHINE- Filed Aug. 23, 1946 e Sheets-Sheet 1 R0) 5. KN/FFEN JUL/AN I? FARNAM W/LBER E WOOLERY 1 ahmwgg Oct. 31, 1950 R. s. KNIFFEN ETAL 2,527,637

BALLAST REMOVING MACHINE Filed Aug. 23, 1946 6 Sheets-Sheet 2 JUL/AN .F? FAR/VAM W/LEER F. WOOLERY OdAfuMm Oct. -31, 1950 R. s. KNIFFEN ETAL BALLAST REMOVING momma Filed Aug. 2:5, 1946 6 Sheets-Sheet 4 R0) 5. KN/FFEN JUL/AN R FARNAM W/LBER Ff WOOLERV Oct. 31, 1950 Filed .Aug.

@wg ca,

F I i f R. S. KNIFFEN ETAL BALLAST REMOVING MACHINE 6 Sheets-Sheet 5 I l!!! H l m! FIE E FILE 1!:

R0) 5. KN/FFEN JUL/AN F! FARNAM W/LBER- F. WOOLERY Oct. 31, 1950 R. S. KNIFFEN ET AL BALLAST REMOVING MACHINE Filed Aug. 25, 1946 6 Sheets-Sheet 6 FIE: 1:1.

aj a

FIE :LE

ROY S KN/FFEN JUL/AN R FARNAM W/LBER F: WOOLERY Patented Oct. 31, 1 950 BALLAST REMOVING MACHINE- Roy S. Knilfen, Duluth, Julian P. Farnam, Minneapolis, and Wilber F. Woolery, St. Paul, Minn., assignors to Woolery Machine Company, Minneapolis, Minn., a corporation of Minnesota Application August 23, 1946, Serial No. 692,636

20 Claims. 1

This invention relates to improvements in ballast removing equipment for railroad maintenance work.

In this field, the removal of the ballast from the roadbed, whether for cleaning and replacement, or in laying new ties, has long been a troublesome, time and labor consuming problem. The ballast has a tendency to become very firmly packed and hardened over a period of time, and this fact, complicated by the difficulty of getting under therails and cleaning out the ballast cleanly clear across the roadbed, between the ties, leads to the many difficulties encountered in the operation. The use of strictly manual labor for the work, althoughlong the established custom, is costly and thus far to our knowledge no completely successful machine has been devised to accomplish the work. Such machines have been either too cumbersome, heavy and expensive, or have been unsafe and difficult to remove from the track when necessary, and in some cases at least have not operated to completely remove the ballast, leaving some for removal by hand labor.

It is the, primary object of our invention to provide a machine for this purpose which will be comparatively light and compact, inexpensive and durable, and safe and convenient in operation. A further' object is to provide a machine whichwill completely and cleanly remove the ballast both between and outside of the rails and which may be operated with a minimum of manual labor.

Other'important objects and advantages of our invention will be made apparent in the course of the following specification, reference being had therein to the accompanying drawings, wherein:

Fig. 1 is a side view of the machine showing it in operating position on the track.

Fig. 2 is a front end view, on a slightly reduced scale, showing the rails and roadbed in transverse vertical section.

Fig.-3 is a plan view of the machine, on the scale of Fig. 2, and with the power plant omitted.

Fig.4 is an enlarged, fragmentary front end view, similar to Fig. 2, but showing the machine justv starting its operation.

Fig. 5 is an enlarged fragmentary elevation of the scraping or ballast ditching or scarifying ele-' ment,'which is hereinafter called the chain;

Fig. 6 is a plan view of'the chain 'as seen in Fig. 5. r

- Fig. 7 is a cross sectional view along the line in Fig. 5.

Fig. 8 is an enlarged, fragmentary elevational' View.

Fig. 9 is an end view.

Fig. 10 is a longitudinal the line l0-l0 in Fig. 6.

Fig. 11 is a longitudinal vertical sectional View of the forward part of the machine, showing certain parts in different positions from the showing of Fig, 1.

Fig. '12 is an enlarged fragmentary sectional detail View.

Referring now more particularly and by refsectional view along erence characters to' the drawing, A designates generally a small railway car to and upon which the ballast remover unit per se, designated generally at B, is mounted. The car A comprises a rectangularframe l5 having frontand 'rear axles Iii-l1 at the ends of which are disposed the usual flanged wheels l8 adapted to run on the rails C of the track. The rails are supported on ties D laid in the ballast E of the roadbed in usual manner.

Mounted at the rear of the car A is a power plant F in the form of a conventional internal combustion engine and the power shaft of this engine emerges forwardly froma clutch and transmission housing G, as indicated at H. An operators seat I9 is provided near the rear of the car and is supported upon a stand 20. If desired the car may, of course, be powered for travel along the track by the engine F although it is not here so shown. Instead the rear axle IT is shown as fitted with a notched wheel with which cooperates a pawl 5| on a hand lever 52 pivotally mounted on the axle and extending upwardly and forwardly alongside the seat l9. By engaging the pawl with the wheel50, and moving the lever the operator may obviously work the car along the track as may be desired.

The ballast remover unit B comprises a main transverse frame structure which, in use, is positioned across and forwardly of the front end of the car A. This frame structure comprises parallel channels or beams 2| and 22 which are rigidly braced and connected and supported one forwardly of the other by U-shaped brackets 23 and any other suitable bracing. The length of these beams 2| and 22 is such that they extend at each end outwardly well beyond the rails C (Fig. 2) and in alignment with the rails the beams are cut out as shown at 24 so that this frame may be lowered below thetops of the rails.

, Short tie beams 25 welded to the upper edges of the beams 2| and 22 span the cut-outs 24 to hold to and extended rearwardly from the rearmost tie beams and are adapted to fit over upright support and guide pins 21 which are rigidly secured to brackets 28 hung from the forward ends of the car A. This mounting obviously permits the frame, and all elements supported thereon, to be raised and lowered with respect to the car and track.

For thus adjusting the frame there is provided a lift mechanism comp-rising levers 29 positioned one to each side of the car A and fulcrumed intermediate their ends, on the car frame sides 30, at 3|. The levers 29 extend forwardly from the car and at their front ends are hooked at 32 to releasably, upwardly engage. rings 33 which are attached to the front tie beams 25 by lugs 34 secured thereto. The pivots 3! support the levers 29 for up and down movements at their forward ends and such movements will obviously correspondingly adjust the frame. At their rear ends the levers 23 beanupwardly on the irregular surface of adjusting cams 35, the upper surfaces 36 of the levers being flattened to properly bear onthe cams, These cams are secured at the ends of a shaft 31 supported crosswise on the car in;bearings .38 secured to the sides 30 thereof. At spaced points, inwardly of the cams, notched disks 39; are also secured tothe shaft and adjacent each disk there is a hand lever pivotally mounted by a tubular hub; 4| upon the shaft. The hand levers 40 are so spaced apart and located as to be conveniently grasped by the-right andleft hands of our ope rator seated on seat l9, and the operator may thus obviously oscillate the levers in a fore and aft direction. On each hand lever is a swinging pawl 42 pivoted at 43 and having oppositely projecting teeth 44. k The pawls 42 may rest o the disks 38 and by swinging the pawls either forward or, rearward of their pivots 4 3 tl 1e teeth 44 may beselectively engaged with the notches in the disks. Thus by properly positioning the pawls and Working the hand levers 4D ;.back;and forth the cams 35.: may be turnedineither direction, and thec'urvature of their cam edges is such that movement in. one direction will push rear ends. ofv the levers 29 downwardly to raise the frame, while opposite. movements-willallow this frame to descend. As a convenience in shifting the pawls 42 about, light cords or chains 4-5; are attached to their free ends and fastened near upper ends of the hand levers 40,;

The shaft 3'! serves also as a convenient support for a pair of foot pedals 46 each .of. which is pivoted at 4'lon the shaft: and held inspaced' relation by a sleet/e48. These foot pedals .may be connected in any appropriate. manner by rods 49 tocontrol the clutch andthrottle (not shown) of the engine F.

The actual digging and scraping. element for removing theballast takesthe form of an openended lengthof heavy chain designated generally at 53 the individual links of which carry shovels or scarifying blades 54. The chain is operated by, and in use meshes in succession with, a series of heavy hold down sprockets or gears 55 arranged between the frame beams 2l and 22 and supported in transversely spaced relation upon shafts 56 journalcd in bearings 51 secured be-.

neath said beams. The axes of the gears 55 are longitudinally and horizontally extended'and the gears so rotated that they all turn. in one. direction so that, as the chain is fed beneath the gears it will be forced transversely from one side of the roadbed to the other beneath the rails C 4 as will be presently described in more detail. The gears 55 are, of course, provided both between and outside of the rails C as clearly shown, and are so located that as the beams 2| and 22 are lowered the gears may be moved down below the level of the ties D and into the ballast. Each tooth of. the gears, except those at the ends of the assembly, has a radially extending and outwardly opening socket 58 (Fig. 12) in which is secured a cutting bit or tool 59 which projects beyond the tooth for a purpose later to appear. Set screws 60 secure the bits 59 in place allowing their replacement when worn by contact with the ballast.

The hold down gears 55 are rotated by an operating sprocket chain 6| which runs around the lower sides of operating sprocket wheels 62 secured on the shafts '56. Between each sprocket wheel 62, the chain 6| runs over idler sprocket wheels 63 journaled in bearings 64 atop the beams 2| and 22 and at the ends of the transverse frameassembly the chain further runs over idlersprocket wheels 65' journaled in bearings; 66 secured to brackets 61 mounted on and connectingthe. ends of the beams. Thus the upper span of chain. 61. is brought. well above the frame and at its. center the chain runs over a drive sprocket car 68 secured to a forwardly extending shaft 59. Obviously the drive arrangement is such'that the. rotation of the shaft 69 and drive sprocket gear. 68 will run. the chain 6| around all of. the operating and. idler sprocket Wheels, running the hold down gears 55alliin the same direction and at the same speed.

The shaft 69' is. driven from the engine F by means which will now. be described. A propeller shaft 79 is connected to the power shaft H of the engine by a coupling. H and extends forwardly above the car through a bearing 12 supported by a bracket l3 (Fig. 3). from a cross member 14 secured upon the car. At its forward end the shaft 10 carries. a. sprocketgear I5 over which runs .a chain .16 also engaging a larger-sprocket wheelt'll laterally offset from the gear 15. The wheel 'l! is secured upon the rear end of a shaft '58 which: is supported at spaced points by bearin'gs 'lll' one of-which is secured upon the cross member 14. The. other. bearing 19 is secured upon a similar cross-member 80 at the forward end of the car. A small sprocket gear 8| is secured-upon the shaft 18 between the bearings l9 and cooperating with thls gear is a chain 82 which runs also over a large sprocket wheel 83. The wheel 83 is secured upon a rear portion of theishaft 89, which is supported, coaxially with respect to shaft 70, in bearings 85 secured to the cross members 14 and 80 It will thus be seen thatshaft 69 will be driven by engine F with a considerable speed reduction afforded by the two chains 'l-6'ancl8 2;

The scraping and scarifying element will now be described As stated above this element comprises an open-ended length ofheavy chain 53 having a plurality of long links each comprising side bars 86 which overlap at adjacent ends and are pivotally connected by transverse pins 81. On one end of the chain there is provided an entering point or needle having side bars 88 secured to the adjacent ends of the link bars 86 by spaced cross pins 89. The needle bars 88 are connected by a transverse web 90 which angles downwardly and rearwardly and the bars are also turned downward slightly and pointed as designated at 9|. For convenience in description this end of the chain, having the needle just described is termed the forward end. The scarifying scrapers or a'ssacer shovels- 54 are secu'redto attachment-plates -92 so spacedand-located-that they-may fit alongside the link bars '86, to which they are then attached by cross--pins 93; The pins 81, 89 and 93 areall evenlyspaced apart alongthe length of the chain, to fit-or mesh with'the teeth on the hold down gears55 as will be apparent.

' The chain 53 can flex or bend in-onl'y one direction and for this purpose the rear ends of the link" bars 8B= have downwardly angling tails or-stop fingers!!! which extend beneath and upwardly engage the forward ends of the adjacent attachment plates 92, when the chain is straight, as olearly shown in Fig.5. Thusupward breaking oriaokknifingof the chain links about the pivot pins-81 4s prevented, but opposite movement is unimpeded. 7

Thescrapers or shovels 54' angle-downwardly and forwardly fromthe chain and at lower edges are beveled'or sharpened as designated at 95. The'bl'ades are welded-to the attachment plates 92- and as clearly shown the blades increase in width and length or depth progressively from the front-end of the-chain to the rear.

Oscillating mechanismis provided for actuating the scraping element with a back and forthmovement as it travels-beneath the hold down gear 55,- and this mechanism comprises a pair of small sprocket wheels 96 and 91 which downwardly engage and mesh with the operating chain 6 l at opposite sides ofthedrive sprocket gear 68. These sprocket wheels 96 and 9!- are journaled at forward ends of stub shafts 98 carried at the opposite ends of a walking beam or lever 99 which is pivotally supported upon theshaf-t 69, behind sprocket gear 68 A heavy leafspring I is secured by bolts llll atopthe lever 99 and projects therefrom laterally-out over a roller I02 carried at the end of 'a crank I03 whichis secured to the forward end of the shaft 18. The crank I93 is thus rotated by the drive mechanism and as it moves upward under'the spring I00 it will rock the spring and lever- 99 clockwise as viewed from the front, moving the sprocket wheel 91 in a downward direction and tightening the upper span of chain fil between the sprocket gear 68- and the right hand end or side of the machine. At the same time sprocket wheel 96 will be moved-- upwardly slacking the'chain 6| slightly'atthe oppositeside ofthe gear 68. This action will'thus cause a sharp jerking impulse tobe imparted to' the chains! in a direction such that the digging chain 53 will accelerate and move forward sharply a short distance, while it travels on beneath the.

gears 55. As the crank I03 moves downward the, sprocket wheels 96 and 91 move respectively downward and upward, as seen in Fig; 4, giving the chains a" slight halting movement between the forward impulses. to accentuate the jerking action. I l

' When not in v use the chain 53 may rest, upsidedown, in a transversely extending trough I05 supported at its ends uponthe brackets 6.1}as.des'ig-- nate'd at I06. The trough has its ends downwardly curvedand flared as shown at I01 and located over the end sprocket gears 55. In the fastenings I06 are embodied openings I08 through which bars (not shown) may be thrust to act as handles in carrying the ballast remover unit when it is removed from the car. as willpresently appear.

Depending from the. beams 2| and 22 are rail stops, IN, (Figs; v2"an'd 4). adapted tov engagehthe sides of the rails C to resist the thrust against the frame as the chain 53 moves through last as will be clearly understood.

In operation, the machine-is moved along the track as required to bring it to the desired point of operations, and during such movement the frameis elevated (Fig. 11) by operation of the levers' lll so that the hold down gears 55 willclear the roadbed and ties. The digging chain 53 is also carried at this point in the trough I05. Whenthe desired point along the track is reached, the

ballast moving unit is lowered by the levers 40" until the gears 55 reach the ballast line. The en-' gine F is, of course,-now in-operation and the rotation of the gears 55 will cause" them to dig-into the ballast, as seen-in-Fig4, breaking up the surface of' the ballast in'advance of operation'of the chain 53, if the downward movement of the The bits feed down off the trough l55-and ainan at this side of the machine will have no difficulty in starting the chainand keeping itin place until its tail end comes off the trough, as will be-apparent."

As the chain travelsits needle end will pass in succession beneath the rails, until this; end reaches the opposite side of the track, whereupon another operator stationed thereat may lift the chain, buckle it over and feed it back onto the trough H35 until the chain is again at rest full length on the-trough, ready fora repeat operation. As will be readily seen the forcefulpassage of the chain beneath the rails will cause the blades 54 to scrape the ballast ahead and'deposit it at the side of the roadbed, leaving a trench clear across the roadbed. Repeated operations may be made to clear out any desired part of the ballast andthemachine may be readily moved ahead or back, and the chain raised or lowered as maybe required; The jerking action ofv the chain as ittravels greatly facilitates its work in breaking' up the firmly packed ballast, and thepene tration of the chain into the ballast is helped'by the gradually increasing size of the scraper blades. The upward'inflexibilityof the chain prevents it from buckling due to the upward reaction of the ballast, and this stiffness of the chain, in combination with the shape of its needle end makes it possible' to pass-the chainbenea-th the rails, from one gear 55 to another atopposite' 1 sides thereof as will be clearly evident.

The open-ended chain, as contrasted to previous devices of our knowledge which use an the frame until the lugs 26 clear the pins 21 The machine is thus readily separated intotwounitsto facilitate removal from the track, storage; or the like. 1

It will'be noted that the :ballast will be re the bal sible, too, to remove the ballast to a level, well below the lower edges of the ties. This is a marked convenience in lowering the track, since by cleaning out the ballast between ties, moving the ties over to drop into the cleaned spaces, and then reballasting, the grade may be lowered with comparatively little labor and time involved.

It is understood that suitable modifications may be made in the structure as disclosed, provided such modifications come within the spirit and scope of the appended claims. Having now therefore fully illustrated and described our invention, what we claim to be new and desire to protect by Letters Patent is:

1. In a machine of the character described; for

forming a transverse channel in the ballast beneath railroad rails, a frame supported over the rails, an open-ended chain having scrapers, and mechanism for supporting and pushing said chain endfirst through the ballast to move a part thereof out from beneath the rails.

, 2. In a machine of the character described for moving ballast out laterally from beneath the rails of a railroad track, a frame supported above the rails, an open-end chain having ballast scraping blades, and mechanism for engaging and pushing the chain crosswise beneath the rails from one side of the track to the other.

3. A ballast remover for moving ballast out to one side of a railroad roadbed from beneath the rails, comprising a parted chain having scrapers, and means for downwardly engaging the chain and forcing it endfirst through the ballast from one side of the roadbed to the other whereby the scrapers will push out the ballast to the side.

4. A ballast remover for moving ballast out to one side of a railroadroadbed from beneath the rails, comprising in combination, an open-ended chain having a series of scrapers, and a series of sprocket gears operatively arranged to engage the chain and push it endfirst through the ballast and beneath the rails and for holding the chain down against the upward reaction of the ballast upon the scrapers.

5. A ballast remover for moving ballast out to one side of a railroadroadbed from beneaththe rails. comprising in combination, an open-ended chain having a series of scrapers, and a series of' sprocket gears operatively arranged to engage the chain and push it endfirst through the ballast and beneath the rails and for-holding the chain down against the upward reaction of the ballast upon the scrapers, the said chain being inflexible in one direction to hold the links thereof from jackknifing upwardly between the sprocket gears.

6. A ballast remover for moving ballast out to one side of a railroad roadbed from beneath the rails, comprising in combination, an'openended chain having a series of scrapers, and a series of sprocket gears operatively arranged to engage the chain and push it endfirst through thecballast and beneath the rails and for hold-' ing the chain down against the upward reaction of the ballast upon the scrapers, the said chain being inflexible in one direction to hold the links thereof from jackknifing upwardly between the sprocket gears, the said chain having a pointed entering memberat the end which moves first through the ballast.

7. A ballast remover for moving ballast out 1' to one side of a railroad roadbed from beneath the rails, comprising in combination, an openended chain having a series of scrapers, and a series of sprocket gears operatively arranged to engage the chain and push it endfirst through 8 the ballast and beneath the rails and for holding the chain down against the upward reaction of the ballast upon the scrapers, the said chain being inflexible in one direction to hold the links thereof from jackknifing upwardly between the sprocket gears, the said chain having a needle member at its end for penetrating through the ballast and said needle member having an angular guide surface operative to prevent its moving angularly down through the ballast and causing the chain to lose contact with the sprocket gears.

8. A ballast remover for digging and moving ballast out to one side of a railway roadbed fromv beneath the rails, comprising a ballast moving element having a series of links, a series of sprocket gears for engaging the links and pushing said element endwise across the roadbed beneath the rails, said sprocket gears being spaced apart transversely across the width of the roadbed and located both between and outside of the rails, the links being connected for flexing movement in one direction only whereby to pass between the gears without upwardly buckling, and ballast digging members on the links.

9. A ballast remover for digging and moving ballast out to one side of a railway roadbed from beneath the rails, a chain having a series of links, a. series of sprocket gears supported across the roadbed and operative to successively engage the chain and force it endwise through the ballast and below the rails, scraper elements on the links, and cooperating means between the links to hold them from upwardly buckling as they pass between the sprocket gears.

10. A ballast remover for digging and moving ballast out to one side of a railway roadbed from beneath the rails, a digging chain having a series of scrapin elements, a series of sprocket gears supported across the width of'the'roadbed and operative to engage the chain and force it endwise through the ballast from one side of the roadbed to the other, and means for intermittently accelerating the sprocket gears and the travel of the chain to assist the chain and the scrapers in breaking loose and moving the ballast.

11. A ballast remover for digging and moving ballast out to one side of a railway roadbed from beneath the rails, a digging chain having a series of scraping elements, a series of sprocket gears supported across the width of the roadbed and operative to engage the chain and force it endwise through the ballast from one side of the roadbed to the other, and mechanism operating on the sprocket gears for imparting forward jerking impulses to the chain as it travels beneath the sprocket gears to assist in breaking out and moving the ballast.

12. A ballast remover for digging and moving ballast out to one side of a railway roadbed from beneath the rails, a digging chain having a series of scraping elements, a series of sprocket gears supported across the width of the roadbed and operative to engage the chain and force it endwise through the ballast from one side of the roadbed to the other, and the sprocket gears having digging means for engaging and breaking up the surface of the ballast before the chain is moved through by the gears.

13. A ballast remover for digging and moving ballast out to one side of a railway roadbed from beneath the rails, a digging chain having a series of scraping elements, a series of sprocket gears supported across the width of the roadbed and operative to engage the chain and force it endwise through the ballast from one side of the roadbed to the other, and the sprocket gears having replaceable radially projecting bits for breaking up the ballast surface in advance of the travel of the chain therethro-ugh.

14. A ballast remover for moving ballast out to one side of a railroad roadbed from beneath the rails, comprising an open-ended chain having a plurality of scraper blades, a series of sprocket gears supported across the roadbed and adapted to downwardly engage the chain and force it endfirst through the ballast and beneath the rails, and the said scraper blades increasing in size along the length of the chain and in a manner such that the smaller blades will first engage the ballast followed by blades of increasing size in succession.

15. A ballast remover for moving ballast out to one side of a railroad roadbed from beneath the rails, comprising an open-ended chain having a plurality of scraping elements spaced along its length, a frame supported transversely above the roadbed, a series of hold down gears spaced across the frame and operative to downwardly engage the chain and feed it endwise across the roadbed and beneath the rails, a sprocket chain operative to rotate said gears, and oscillating mechanism for periodically pulling said sprocket chain sharply in one direction to impart forward accelerating impulses to the scraping elements as they travel through the ballast.

16. A ballast remover for moving ballast out to one side of a railroad roadbed from beneath the rails, comprising an open-ended chain having a plurality of scraper blades, a series of sprocket gears supported across the roadbed and adapted to downwardly engage the chain and force it endfirst through the ballast and beneath the rails,

and means operative to engage the rails and resist the backward thrust upon the chain and gears as the scraper blades push through the ballast.

17. In a machine for removing ballast out to the side of a railroad roadbed from beneath the rails, a frame supported crosswise above the roadbed, a series of hold down sprocket gears car ried by the frame and spaced apart across the roadbed, an open-ended chain having a series of digging elements, a trough supported above the frame and having its ends positioned over the end gears of the series, and the chain being adapted to be supported between ballast removing operations in an upside down position in the 16 trough and to be fed endwise therefrom dow'riwardly beneath the gears for movement by the gears across the roadbed and then lifted and fed back onto the opposite end of the trough and returned to an inoperative position on the trough as the operation is completed.

18. In a ballast removing device, an elongated heavy open-ended chain having a series of pivotally connected links, scraping elements projecting in one direction from the links, and cooperating means on the links for restraining them against flexing movements in a direction opposite that in which said scraping elements project.

19. In a ballast removing device, an elongated heav open-ended chain having a series of pivotally connected links, scraping elements projecting in one direction from the links, cooperating means on the links for restraining them against flexing movements in a direction opposite that in which said scraping elements projest, and a needle member on one end of the chain having a pointed end and an angular guide surface for engaging and guiding the chain through the ballast.

20. In a machine for removing ballast out to the side of a railroad roadbed from beneath the rails, a frame supported crosswise above the roadbed, a series of hold down sprocket gears carried by the frame and spaced apart across the roadbed, an open-ended chain having a series of digging elements, means for operating the sprocket gears to thrust the chain end first through the ballast, and a trough supported above the frame for supporting the chain when not in use and as it is fed down at one end into engagement with the sprocket gears.

. ROY S. KNIFFEN.

JULIAN P. FARNAM.

WILBER F. WOOLERY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,588,801 Overmier June 15, 1926 1,687,313 Robb Oct. 9, 1928 1,691,933 Overmier Nov. 20, 1928 1,817,524 Protzeller Aug. 4, 1931 2,144,313 Klauer Jan. 17, 1939 2,144,316 Klauer Jan, 17, 1939 2,254,742 Humphrey Sept. 2, 1941

Images