US1075741A - Draft-rigging. - Google Patents

Description

= To all t concern v lslack to 'be l y @NT-TED STATES PATFN T FFTQE.

JAMES MILTON-WAUGH, OF CHICAGO, ILLINOIS.

DRAFT-meente.

Be it known that I, JAMES MILTON VVAUGH, a k'citizen 'of the United States, and a resident of the city of Chicago, yin the countyj o f oo'k and State of Illinois, have invented certain new and useful VImprovements in DraftfRiggings; and I do' hereby declare `that the following is a full, clear, and exact description of the same, referencebeing had to the accompanying drawings, and yto the letters of reference marked thereon, which .form a part of this specification.

Many of the railways at the present time are equipped with friction draft rigging of various v types, wherein co-acting wedge blocks 'are secured within a'casing together with Springs lin Various forms andl these wedge blocks by frictional' engagement, were supposed 'to absorb bufing stress.- As a matter of"fact,'years lof experience with such equipments have demonstrated that the faces of the Wedge blocks are in .constant movement relatively each other when a train is under motion, such movment being due to the varying stress due in part to the inequalities of the road and variations in grade so that during the entire operation vthe faces of the wedge'blocks are ground together, soon prodining such wear` as to cause considerable resent, of course, very materially decreasing the efficiency of the draft gear so far as absorbing stresses is concerned and in very many instances, rendering the draft gears of `this type practically wortli` less. In consequence, roads previously equipped with such devices are abandoning the same to a greater orless extent and it has become an important problem how best to effect a change from draft riggings such as described to another type, with the least possible expense for renewals and labor.

The object of my invention is to insert with the least possible change in the existing equipment and the least possible expense for material and labor, a draft rigging of the type set forth in my prio-r patents for draw bar draft rigging for car couplings, No. 690,683, dated Jan. 7, 1902; draft rigging for railway cars, No. 690,684, dated Jan. 7, 1902; draft rigging for railway cars, No. 705,172, dated July 22, 1902; draft vrigging for railway cars Nd 731,725, dated J une 23, 1903.; draft rigglng for railway cars No. 818,066, dated 'April 17, 1906, whereby although an ideal friction rigging', `practically no wearing 'effect can Specification of Letters Patent.

'Patented Get. la, 1913.

Application filed October 10, 1908. Serial No. L157,050.

occur, and furthermore to afford such frictionally controlled resiliency as 'to insure the maximum absorption of all the-stresses whether bufing or pulling.

It is finally an object of the invention to afford an exceedingly cheap, simple and durable construction for the purpose specified adapted to be inserted in lieu of such draft gear before described without the aid of skilled labor.

The invent-ion consists in the matters hereinafter described and more fully pointed out and defined in, the appended claims.

In the drawings: Figure 1 is a fragmentary, central vertical section of a car frame embodying'm'y invention and showing the tail strap for the draft gears in section and `likewise the casing and springs therein.

Fig. 2 `i's a fragmentary horizontal section showing the center sills, the tail strap and casing and springs.- Fig. 3 is a section on line 3-#3 of F ig'. l. Fig. l isa perspective View of the abutment block. Fig. 5 is a side elevation of the spring casing embodying -my invention.

As sh'own in the drawings: A, indicates the center sills, and 0:, the end sill. Said center sills, as shown .in Fig. 3, are pressed or rolled Z bars, havingthe top flanges directed inwardly 4and the lower flanges a', directed outwardly, and connected below the draft gear by lpressed or rolled sheet steel filler affording side ledges'a2, and a depressed bottom' ledge or floor a3, affording together with the center sills a compartment for the draft gear. Rigidly bolted and riveted on the inner sideof each center sill near the outer end thereof, are the stationary abutments B, and at a distance therefrom and inwardly equal to the length of the desired drfift rigging are the inner abutment blocks B. These, as shown, comprise inward right angle shoulders against which the follower blocks babut in practically any type of draft rigging and suitably supported and x'tending beneath the end sill is,`

the draw-bar C, to which is connected the tail strap C, usually of wrought steel and which is forged or shaped to afford a U shaped strap, the ends c, of which extend one above-and the `other below the tail of the draw bar, and 4are riveted or bolted thereto, as shown in Figs. 1 and 2. The upper side of said tai-l strap C', extends `to near 110 the top of Athe sills', as show-n 1n F1g.`3, and

the lower 'side thereof extends to hear the floor c3, of the 'filler between the sills and which serves as a guide and support fort-ho draft rigging.

inserted within the tail strap with the rear or inner end bearing against the fol.- lower block o', the casing l), of malleable iron or other suitable material which, as shown, is roughly rectangular in form with reentrant angles at the corners, as shown in Figs. 3 and 5, thus reducing the widths of each of the sides of said easing to a size approximately suitable to lit between the walls afforded by the shoulders a2 and to till the yoke vertically of the draft gear described. Said casing, as shown, has arranged therein a plurality of short, thin steel plates of high resiliency and arranged, as shown, in live groups, the inner cZ, consisting as shown, of eleven plates, the next adjacent group al, consisting of ten plates, and the next outer (Z2, the next group Z3 and the outermost group dt, also consist-ing of eleven plates. As shown, the two outermost groups are separated from each other by a spacing block d5," having concaved and inwardly tapered sides and connected at their inner` thin edges. Said spacing blocks d5, are connected centrally by means of a thin web or plate (ZG.

The groups ZL-Z2 are separated by an oval spacing bleek (Z7, against which said groups bear at their center from which point said oval spacing block tapers convexly toward the ends, which extend closely to the sic es of the casing D. Between the groups (Z Z2 is interposed spacing blocks cZS, identical in construction with the spacing block (Z5, beforel described, and also connected l.:y a web blade CZ. 'lhe groups f;Z-CZ, are separated by a full oval spacing block d10, identical in construction with the oval spacing block (Z7, and sine-.ilaria disposed and as shown, the ends of said inner groups of springs cZ, bear `against.- the inclined inner portion of the casing, which is eoncaved to afford a distance between the center of the last plate of said group and the inner end of the casing e= ual to the distance between the spacing web d or CZ, andthe adjacent spring plate.

The abutment bloclr E, is shaped transversely to lit in the end of the spring easing D, and as shown in '2 and 4l, is convex on its'inner end having the saine eonvexity as one side of one of the full ovals and bears at the center of the outer group of plates. As shown also, said abutment is provided at its inner end with an upper and a lower flange ca -e', which fit into the space in said easing above and below the spa'ings and eX- tends inwardly for some distance to insure said abutment telescoping into said casing under bui'ling 'stress or pulling stress and preventing at all times the displacement of the abutment from position. The forward end of the abutment is s uare, as shown, with the side walls thereo bearing firmly against the forward follower block b.

The operation is as follows: The casing D, with the springs inserted therein in groups in the order shown in Figs. l and 2, with the spacing blocks in place, the full ovals being arranged alternately between the concave end blocks, so ythat said groups of springs are engaged by said spacing blocks .alternately at the ends or the middle, as

shown, the abutment block bearing `against the middle of the iii-st group of springs and the inner group bearing at its ends against the inclined end walls of the casing. 'v When buiiing 'stress is applied, the tail of the draw-bar being in positive bearing against the follower block Z), the butting stress is del livered centrally upon the first group of springs tending to flex the same moreor less and inasmuch as said springs are flat and ot equal area, and in positive bearing for their entire surface one upon another, it folhrws that enen a very slight relative movement of the plates in a group must of necessity produce very great surface friction, the frietional surface in each group in that ease being obviously the sum of the areas of the number of plates less one, inasmuch as the outer surfaces of the outermost plates of each group are not in frictional engagement. Inasmuch as the outermost group contacts only at the ends as does the next adjacent group (Z3, which group bears at its middle on the oval d?, and the gro-up (Z2, again at its middle and ends, or, in other words, inasmuch as the groups are in bearing alternately at their ends and at their middle, it follows that sudden `inward stress due to buiiing 'is transmitted to the entire number of groups, the outermost groups, however, receiving the first impulse to a slight' extent and must sustain the greater stress. Owing to the construction of the alternate arrangement of' the movable full oval spacing blocks and the inwardly tapering backs, it is obvious that the distance between the .contact .faces on the spacing blocks decrease. as compression increases and furthermore that whatever the bu'tling stress, practically the entire force thereof is ab,- sorbed by the surface friction between the plates as well as by the resiliency and having driven the plates inwardly to full or less than full compression, the friction between the plates tends to prevent recoil by absorbing such stress frietionally, lthat is to say, there being some pressure maintained upon the draft gear at all times, and whatever tlie resiliency of the spring plates the frictional pressure of the plates one upon another must be overcome before appreciable recoil can take place, and such frictional pressure, although very sligl1t-ly,when considered in relation to the entire frici .the'number of groups.

notant tional area of the plates is amply sutlicient to account for the absence of recoil. The stresses exerted in pulling are absorbed in much the same manner. The draft of the taiL strap on the-follower block lf, forces the spring casing with its content-s forwardly upon the abutment E, which, of course, is held from movement von the follower block b, which is in full bearing upon the stationary abutinents B. ln consequence, all the springs in each group are flexed slightly, the amount being ofcourse, `dependent in part upon the stress and upon the number and thickness of the plates and In practice, it has been found that no appreciable attrition or surface Wearing of the plates occur for the reason that the frictional surface being enormously great owing to the large number' of plates and the larger surface of each exposed it follows that even with the enormous stress due to bufing, the actual frictional pressure ap plied on each plate per square inch is relatively small although the frictional effect produced is suflicient to confine the travel in the draft gear to very small limits. The ordinary stresses produced in such a draft gear when the train is in motion produces exceedingly slight movement -in the plates 'relatively each other and in consequence, the

grind and wearing effect heretofore present in friction draft gears is absent inasmuch as in lieu of the very small friction surface provided in standard friction draft gears, the actual frictional surface utilized is enormously great and. this friction surface may be increased by increasing the number of plates or the number of groups of plates or both.

Although l have heretofore used spring plates approximately one fourth inch in thickness, I have found in practice that excellent results are attained by the use of such spring plates approximately one eighth of an inch in thickness, thus enabling the greater number of plates to be used in a given space and proportionately increasing the frictional absorbative power of the gear.

Of course, l am aware that the casing may assume other forms than that illustrated and described, and if desired, other features in the invention may be varied. l therefore do not purpose limiting this application for patnl otherwise than necessitated by the prior art, as numerous details of construction and application may be varied without departing from the principles of this invention.

'l' claim as my invention:

l. ln a4 draft ing the combination with the draw bar 'yt e and follower bloc Is inserted therethrough to hear respectively against the front and rear stops, of a spring casing slidably supported in said yolre and bearing at one end against one of the follower blocks, an abutmentblocl; bearing against the other follower block and extend ing into the casing, a plurality of groups of flat, thin spring plates arranged within the spring casing, each group movably supported in the casing and the groups separated alternately at the middle and ends and guide flanges integral with the abutment block andvextending into tl-e casing on opposite sides of they spring groups.

2. In a. draft rigging the combination. with a draw bar yoke of a chamber, having a central longitudinal channel in the lower wall to receive the yoke therein, a much smaller spring casing constructed to provide a guide portion to fit in the channel and shoulders to rest on the lower wall, spring friction'plates arranged in groups in the casing, concave and convex bearing blocks separating the groups of spriiig plates alternately at their ends and their middles and an abutment blocl; fitted in one end of the small spring casing and guide flanges thereon extending into said casing on each side of the spring groups;

8. In a device of the cl i described a ing having rentrant angles at the corners thereof providing internal and external guides, spring plates adapted to lit in the casing and an abutment block adapted to tit in the end of the casing.

Ll. ln a device of the class described a cas ing having an integral end wall curved on its inner side, spring plates therein, concave and vconvex spacing members dividing the springs into groups, a bearing block curved on one end adapted to lit in the casing and. guide members integral therewith extending into the casing on each side of the spring groups.

In testimony whereof l have hereunto subscribed my name in the presence of two subscribing witnesses.

JAMES MlLTOll lVAUGll.

lVi tnesses K. E. HANAH,

J. lV. ANGELL.

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