US3358614A - Snubbed railroad car truck - Google Patents

Description

Dec. 19, 1967 BARBER 3,358,614

SNUBBED RAILROAD CAR TRUCK Filed Nov. 16, 1964 United States Patent Ofiice 3,358,614 Patented Dec. 19, 1967 3,358,614 SNUBBED RAILROAD CAR TRUCK Franldin D. Barber, Chicago, Ill., assignor to Standard Car Truck Company, Chicago, 111., a corporation of Illinois Filed Nov. 16, 1964, Ser. No. 411,391 1 Claim. (Cl. 105-197) ABSTRACT OF THE DISCLOSURE This invention differs from the usual friction wedge railroad car stabilizing apparatus in that the inclined surface between the bolster and the wedge are at 45 degrees to the horizontal instead of the usual 60 or more degrees and wherein, as a result, the horizontal component urging the wedge against the usual horizontal wear plate is reduced to a point such that the Wedge biasing springs may carry a substantial proportion, approximately 20% of the load applied by the bolster to the car frame as distinguished from the negligible load carrying character of the usual biasing spring.

This invention relates to improvements in stabilized railway car trucks of the type wherein vertical oscillation of the truck bolster is damped by means of friction shoes biased into friction relation between the truck and the bolster by wedge actuating springs.

Railway car trucks habitually include two windowed side frames with a truck bolster extending across the truck and vertically movable at each end in the side frame Windows, the bolster being supported by load carrying springs between the side frames and the bolster ends.

Pockets are defined in the side frames or the bolster preferably the latter, to receive wedge or friction shoes. Each shoe has a vertical friction surface preferably engaging a friction surface in the side frame and an inclined wedging friction surface preferably engaging an inclined friction surface on the bolster. Usually there are two such wedge and pocket assemblies at each end of the bolster.

Conventional practice has been to have the inclined mating surfaces of the wedge and pocket in the order of thrity-five degrees with respect to the vertical. This acute angle has been thought to be important because it results in a high degree of pressure between the mating frictional vertical surfaces of wedge and frame with the use of actuating springs of substantially less strength than the load supporting springs. As a matter of fact, standard practice provides that the portion of the load of the car supported by the wedge springs is negligible and the load supporting springs between the side frame and the bolster are designed to carry the entire weight of the car. The reason for this is that it has been thought that wedge springs strong enough to support a substantial part or" the load would tend to lock the wedges and interfere with spring action.

This invention proposes a different arrangement. The inclined mating wedge surfaces of the friction shoe and the pocket are at an angle of generally forty-five degrees to the vertical. Thus the component of lateral pressure between the friction shoe and the vertical friction surface is Very much less than it would be if the inclined surfaces were at thirty-five degrees. As a result, in order to obtain adequate friction resistance, a much heavier stronger wedge actuating spring must be used and this wedge actuating spring can then effectively support a substantial proportion of the weight of the car.

It is proposed therefore that instead of an acute thirtyfive degree angle wedge, a forty-five degree obtuse angle wedge will be used and instead of supporting a negligible part of the load of the car, the wedge actuating springs will in a substantial proportion support fifteen to twenty percent of the total load. This requires a spring perhaps less powerful than the load supporting spring but which does not furnish suflicient pressure to cause locking of the wedge between the bolster and the side frame.

This makes it possible to use a wedge, the base of which is relatively long in a direction perpendicular to the axis of the frame bolster. Thus, without any change in the windows in the side frame, there is room for a plurality of combined wedge and car supporting springs while leaving also room for the single function car supporting springs. As a result it is possible to have the wedge springs support a relatively greater proportion of the car load and provide both damping effect and load carrying effect.

Because the angle of contact between the Wedge and the bloster is forty-five degrees instead of thirty-five, this increased spring pressure on the wedge can be permitted without the danger of locking the wedge between the bolster and the truck frame. Of course, by slight rearrangement of the main load carrying springs, a single stronger or heavier wedge spring might accomplish the same result. The point is that by the combination of the forty-five degree wedge angle plus a more powerful spring support for the wedge, the wedge springs may support a much larger proportion of the car weight without the danger of locking the damping wedge.

Other objects will appear from time to time throughout the specification and claim.

The invention is illustrated more or less diagrammatically in the accompanying drawings, wherein- FIGURE 1 is a fragmentary side view of a part of a railway car truck in part section provided with stabilizing mechanism according to the present invention;

FIGURE 2 is a section along the line 22 of FIGURE 1;

FIGURE 3 is a section along the line 33 of FIGURE 1.

Like parts are indicated by like characters throughout the specification and drawings.

Because the truck frames on opposite sides of the car truck and the relation between them and the bolster ends are identical, drawings and description in the interest of simplicity are limited to the arrangement of one side of the truck.

The truck structure shown herein includes, in its general organization, a bolster 10 supported on load springs 11 seated on a lower tension member 12 of a truck side frame 13. The opposite side walls of the bolster are provided with pockets 14, 15, the rear walls 16, 17 of which incline upwardly and outwardly toward the side walls of the bolster at an angle of approximately forty-five degrees so as to impart to each of said pockets a Wedgeshaped configuration. Friction wedges 18- are housed in said pockets 14-, 15' in positions to bear against opposing columns 19, 20 of the side frame 13. Wedge actuating springs 21 associated with the wedges maintain the said wedges in their operative positions between the bolster 10 and the columns 19, 29 of the side frame.

The wedge actuating springs 21 associated with each Wedge 18 compressed as they are between the wedge and the bottom face of the bolster are so positioned that the vertical center lines of the wedge springs are in a vertical plane which includes the longitudinal center lines of the wedge springs are in a vertical plane which includes the longitudinal center line of the truck frame and are equidistant from a vertical line in said plane which passes through the center of the inclined wedge surface.

The load springs 11 are located as indicated in FIGURE 3 on both sides of the truck frame with space between them for the wedge actuating springs 21. The load springs 11 are centered by lugs 22 on the truck frame and bolster.

The wedge springs 21 are centered by lugs 23 on wedge and truck frame to maintain all said springs with their' center lines in vertical position between the truck frame and bolster or between the truck frame and wedge.

The truck columns 19, 20 are positioned in spaced relation to each other and connect the lower tension member 12 with a top compression member 24 in a manner to define a window opening 25 for receiving a box end portion 26 of the bolster 10. The compression member 24 and the tension member 12 converge toward their extremities and are united with each other to provide a pedestal construction adapted to be supported on a conventional housing 27 enclosing a journal and bearing of an axle (not shown) but associated with the wheel 28.

The box portion 26 of the bolster projects through the window opening 25 and is provided with inboard and outboard guide lugs 30, 31 which embrace the inboard and outboard side faces respectively of the vertically extending columns 19, 20 of the frame so as to interlock the bolster with the side frame. Wear plates 32, 33 of hardened steel are interposed between the wedges 18 and the vertical columns 19 and 20 of the side frame, the wear plates being suitably secured by welding or by other conventional means to the inner faces of said vertical columns.

In order to facilitate the assembly of the bolster end 26 in a side frame 13 of a truck, the lower portion 34 of the bolster window 25 is made of sufficient width to permit the outboard lugs 31 on the bolster to pass therethrough. Preferably, the upper ends of the lugs 31 stop short of the top face of the bolster so that the enlarged portion 34 of the bolster window 25 may be made of minimum height. After the outboard lugs 31 clear the outer faces of the columns 19, 20 the bolster may be elevated to a position within the window 25 to permit the load springs 11 and the wedge actuating springs 21 to be inserted in their operative positions beneath the bolster and the wedges respectively.

The arrangement whereby two Wedge supporting springs are used located on the center line of the truck frame makes it possible to bring the load bearing springs more closely toward the center line of the frame but if a single spring is used, it will be placed with its center line in the center line passing through the forty-five degree inclined surface of the wedge. Such a spring would need to be of larger diameter and could be accommodated by more widely spacing the load carrying springs along the bolster.

If for example the four load carrying springs have a total capacity of fifty-four thousands pounds, the wedge actuating springs on each side will have a capacity of perhaps six'thousand' pounds or if but a single wedge carrying spring, that single spring would have that capacity. The result of this is that the wedge actuating springs will carry in the order of fifteen to twenty percent of the total load so that a smoother movement occurs and all the springs assist in carrying the load without danger of locking the wedge.

If for example a downward load M is applied to all the bolster springs, the load supporting and the wedge supporting springs all together take the load. On the upward travel, however, because of their dual function, the action of the friction springs will not be quite as fast as the reaction of the bolster springs but they will still continue to cooperate with the load carrying springs in the operation of the device but lock up of the Wedge is prevented and the shoes will quickly be oriented into a position in which the wedge shoe actuating springs will assist in carrying the upward load.

I claim:

A stabilized car truck including a side frame having a bolster window therein, a bolster having a box end portion projecting into said window and formed with wedge receiving pockets opening through each side face of the bolster and formed with a rear wall provided with an upwardly and outwardly inclined face, load springs interposed between the bolster and a subjacent portion of the side frame to resiliently support the bolster with capacity for vertical movements relative to the side frame, means for damping vertical movements of the bolster comprising a wedge element positioned in each pocket for cooperating wedging engagement with the inclined face thereof, vertically disposed friction plates mounted on the side frame, each wedge having a vertically disposed friction surface in opposition to a plate on the side frame, wherein the maximum Width of each wedge is substantially equal to the distance between the center of the bolster and the opposed vertical wear plate on the side frame and there are a plurality of wedge springs interposed between the side frame and the under face of each wedge, the springs being positioned along the longitudinal axis of the side frame.

References Cited UNITED STATES PATENTS 2,053,990 9/1936 Goodwin l05-l97 2,237,953 4/1941 Webb l05197 2,257,109 9/1941 Davidson l05197 2,413,458 12/1946 Light l97 2,485,973 10/1949 Lehrman 105-197 2,702,512 2/1955 Maatman 105-l97 ARTHUR L. LA POINT, Primary Examiner.

H. BELTRAN, Examiner.

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