US1485981A

US1485981A - Truck for railroad rolling stock

Info

Publication number: US1485981A
Authority: US
Publication date: 1924-03-04
Anticipated expiration: 1941-03-04

Description

March 4 1.924.`

R. V|=. HALL TRUCK FOR RAILROAD ROLLING STOCK' Filed Nov. 29. 1922 3 Sheets-Sheetl WITNESS 5 7d/MM March 4 1924.

R. F. HALL TRUCK FOR RAILROAD ROLLING STOCK Filed NOV. 29. 1922 3 Sheets-Sheet 2 i '/f" fd. H3154 March 4 1924.' 1,485,981

. R; F. HALL TRUCK Fon RAILROAD ROLLING STOCK Filed Nov. 29A 1922 3 Sheets-Sheet 3 wrmsss fully set orth.

Patented Mar. 4, 1924.

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einen am wanneer ze, im. semi n mie.

To all whom it may concern.' f

Be it known that I, Boem citizen of the United States, vresiding at Schenectady, in the county of Se and State of New York, have invented a certain new and useful'fm rovenient in Trucks for RailroadRolling teck, of which improvement the followingis a specification.

My invention relates to trucks for railroad rolling stock of the class or type in which lateral resistance devices are provided, and is an` improvement on that set forth in Letters Patent of the United States No. 1,060,222, granted and issued to W. E. Woodard, under date of April 29, 1913.l

The object of my invention is to provide means whereby the resistance op osing the lateral movement of the truck bo r shall be caused to continuously decrease, coincidently with, and proportionately to, the increase of lateral movement of the bolster, thereby limiting the'extent of vertical elevation of the bolster for a given lateral displacement, and exerting a relatively high resistance durin the initial movement of the bolster from its normal central position. A further object of my invention is to ro vide means for exerting a resistance iv ich increases as the lateral displacement of the bolster increases.

The im rovement claimed is hereinafter In the accom an ing drawings: F' re 1 is a view, half iii elevation and half xfiuvertical central transverse section,.'of a two wheeled locomotive leading truck, embodying my invention; Figs. 2 and 3,(simi'lar sections through .the'ftruck frame and bolster showing, -respectivel the bolster moved from normal centra position thro h the distance aand through the distance Fig.

4, a diagrammatic' 1an view, showing the disposition of the w eels of a 2-8-0 type locomotive on a curved track and the extent of lateral displacement of the bolster on such a curve;

Fi

5, 6 and 7, views, shoi'lv-V ing one of the roc ers of Figs. 1, 2 and 3,. with indications of. the relation between the vertical and horizontal forces acting on the bolster and rocker and their resultant, and, Figs. 8 and 9, similar views, showing the two positions of an increasing resistance rocker, with indications of the foreesexerted in the two ositions shown.

In swingor lateral motion type trucks F. Heu., a bea henectady `oi'i'ritdii,

"when displaced from their normal mi inclined bottom rl 4 rocks plied,- t e faces of the cam rockers are curved the centree of which are coincident ,"with the axes of the segmental 'ournals of "the cams, about which the roc ru swi e pgsitions. Inthe lateral movements of the lster, the inclined bearings thereof move on the cam faces of the rockers, and the bolster is elevated, to an extent determined b that of the lateral displacement of the bo ster and the inclination of its beari For example, if the bolster beari are inclined- Vone inch vertical rise for eac rojected horizontal length, the bolster will D 4 raised one inch vertically for each 4 inches of lateral displacement, and other values of horizontal displacement will be accompanied by roportionate vertical elevations.

e extent of lateral dis lacement of the bolster varies directly wit the wheel 'base pro lortions of the locomotive, and inverse] wit the radius of curvature of the track. t vis also the practice, on some types of Incometives, to provide for additional lateral motionon t eextreme pair or pairs 0f driving wheels, in which case the extent of lat "eral displacement ,on a curve ofvdeterm radius is increased.

On locomotives having a comparatively long wheel base,

it is desiriv ble-to provide a high lateral motion ristance in the leading truck, to assist in guiding the locomotive around curves, but the combination of a high 'lateral motion resistance, on a locomotive fof this character, with a lar' extent'of lateral displacement, involves ability to an undesirably great elevation of the bolster, tending to distort the spri ging, etc. In order to reduce'the extent of this elevation, the rockers are, in accordance with my invention, designed to give a relatively higher resstane, at the homing of the lateral displaeem t, and a l ntially lesser resistance et t e full traverse 4 on. The extent of elevation of the bolster then be comes approximately the meen of the sum of from the initial to the final posit:

the elevations which' would be efected, with l@ 4 inches ofk 'lq of the VIl bolster, the resistance decreasirg iiniformly l It has also developed in practice, that locomotives equipped with a, leading truck and no trailing truck, are subject to'derailment when backing on curves, as in' the case foi those of the consolidation or 2-8-0 4,' t

, this condition being due to the fact at, in backing, the leading truck tends to Crowd a rear dr1ving wheel against the outer rail and to increase the flange pressure on thatl driving wheel. A reductionof the 4 lateral resistance of the leading truck tends of the locomotive to nose; should be less when running on-the comparatively long rad1us curves oli-which the locomotiveop- .crates in continuous runs: and should be least, or entirely absent. when the locomotive` is, on curves ofr comparatively short radius, such as those 'on Ys and turnouts. Vith the leading truck resistance substantially eliminated. on the short `radius curves last'reerred to. the {iange pressure on the extreme driving wheelsbecomes practically the same for the going` ahead and the backing movements. and the flange pressure on an extreme driving wheelV in backing is lcss than it would be if the leading truck exerted lateral resistance. The shorter the radius of the curvegwitha given length of rigid wheel base, the sharper will be the angle that the flange ofvan extreme driving wheel makes with a tangent to the curve at that point, and the greater will be the tend ency to der-ailment.l It' follows. consequently, that on the main line curves of relatively'longer radius, a greater flange pressure may be exerted without tendency to de,

`My4 invention is herein exemplified as applied in a twowheeled locomotive. leading truck of the swing or lateral motion type. in which. as in present=practice. a frame. l, is supported through fthe intermediation of springs. 11.on the-journal boxes. 2lfrof an axle, 5. on which the tmc-.k wheels. 5. are secured:l bolster support.A (Lc'xtends from one 'totlieother of theisidc members of the truck frame to which it is rigidly secured at its ends.V The weight carried by the truck is primarily applied thereto through a floating orrswing bolster. 7, which is provided withabentre' plate. 78. perforated for the passage of a centre pin. The bolster is sup ported, with the capacity ofrel'ative lateral movement, relatively to the truck frame, on the double curved upper, bearing faces of two counterpart cam rockers, 9*, upon each of which it abuts by double upwardly inclined'or V"shaped bearings, 7", formed on its lower side. The cam rockers are ada ted to swing, in one or the other direction, a ut the axes of segmental journals, 9", extend lng, parallel with the longitudinal centre line of the truck, on opposite sides of their bases, and fitting in correspondingly rccessed bearings in the bolster support, 6.

In the practice of my invention, and as constituting its primary and essential characteristic feature, I provide, in a truck of the character hereinbefore described, cam rochers, 9, in which the bearing surfaces, 9, instead of being curved on radii, the centres of which are coincident with the axial lines of the journals o'n which ,the lockers swing. as in lprior practice, are curved on radii, which are not coincident with said axial lines, that is to say, the centres of curvature are located either above or below the axes of swinging movement, thereby imparting a greater or a lesser degree of convexity to the bearing faces of the cam rockers, as the case may be. In the case of the loca tion of the centres of Vcurvature above the axes of swinging movement, the lateral resistance imparted to the bolster decreases continuously. as the lateral displacement of the bolster increases. and in 'the case of the location of the centres Aof the curvature be `low the axes of swinging movement. the lateral resistance imparted to the bolster increases continuously. as the lateral displacement of the bolster increases.

Figs. 5, 6 and 7, the cam rockers. 9*, of which are similar to those of Figs. 1, 2 and 3, show the bearing surfaces, 9, of the rockers as curved on radii, the centres, m. of which are located above the axes of swinging movement, and` in Figs. 8 and 9, the bearingr surfaces of the rockers are shown as curved on radii, the centres, y, of which are located below the axes of swinging movement. lnthe operation of rockers of the form shown in Figs. 5,' 6 and 7, there is developed an increasing'tendency ofthe bolster to slip on the surface of the rocker, the magnitude of which l tendency is approximately measured by the tangent of the angle, z, which a line normal to the inclined surface Vof the bolster, makes with a line joining the axis of rotation of the rocker with the ts'mgentA contact point of the bolster on the rocker. For example, in a disposition giving 25 per cent initial resistance and zero resistance at full travel` if the inclination of the bolster bearings was made one in four (25 per cent) the angle, z, would be zero, in the initial central position, andthe tangent of that angle in the final position would be equal to the bolster ,bear-V ing inclination. -i. e., 25 per cent', or.h in other words, the tendency of the bolster to slide on the rocker in the final position would be measured by 25 per cent of the vertical load.

In order to reduce this slipping tendency at the end of the bolster movement by diB- resistance. For example, as shown in the drawings, the inclination of the bolster bearings is one in six (16?, per cent) By suitably locating the centres of the bearing surfaces of the rockers, the positions of the tan ent contact ints of the bolsterl on the roc ers are so shifted, relatively to the axes of swinging movement, as to aord an initial resistance of,25 per cent. Under this condition, there will be a slight tendency for the bolster to slip on the rockers, in its initial osiltion, but ,this tendency, at the end o the traverse of the bolster, is reduced to approximately l'per cent, instead of 25 per cent, of the vertical load.

It will, however, be obvious that any suiti able and preferred inclination of the bolster bearin may be adopted, without departure from t e spirit andoperative principle of my invention.

I claim as my invention and desire torsecure by Letters Patent:

1. In a railroad truck, the combination of a framega bolster adapted to traverse laterally relativel thereto; and a swinging rocker, journall in bearin on the frame extending transversely to t e bolster, said rocker having cam surfaces abutting against the bolster, which cam surfaces are curved on radii, ,the centres of which are exterior to the axial lines of the rocker journals.

2. In a railroad truck, the combination of a frame; a bolster adapted to traverse laterally` relatively thereto; vand a swinging rocker, journalled in bearin on the frame extending transverselyv to t e bolster,l said rocker having cam surfaces abutting against the bolster, which cam surfaces are curved on radii intersecting lines parallel with the faces adapted to a axial lines of the rocker journals and on centres located exterior to said axial lines.

3.' In a railroad truck, the combination of a frame; a bolster' adapted to traverse laterally relatively" thereto, and having ity of double inclined or V-shape bearings,

.the tangent of the angle of the inclined surface of said bearings with a horizontal line being less than the ratio of the maximum re-` sistance to lateral displacement of the bolster', to the vertical load imposed on the rockers; and a swinging rocker, Journalled in bearings on the frame extending transversely to the bolster, said rocker having oppositel curved cam surfaces abuttin against the arin of the bolster, and ing curved on ra ii struck from centres inside the axial lines of the rocker journals on the side of the rocker opposite toy that on ,which they are' located. 4. A rocker for lateral motion railroad trucks, having oppositely curved cam sur-` ut against bearings on a bolster, and journals, transverse to its cam surface, on its lowerends, said cam surfaces being curved on radii the centres of which are exterior to the axial lines of the rocker journals.

5. A rocker for lateral motion railroad trucks, having op ositely curved cam surfaces adapted to aliut against bearings on a a pluralbolster, and journals, transverse to its cam l I VROBERT F. HALL.

Witnesses:

C. KENNETH Geremia, BER'rHA C. FABosKAY.