Resilient Roll Controlling Railway Car Side Bearings

Abstract

A device for positively establishing a maximum allowable roll angle for a railway car, without detracting from the capability of the car to move, in a horizontal plane, relative to its trucks. The device utilizes a strong but yet resilient rubber-like material in limiting the roll of the car. In some instances, the material is combined with shock absorbing coil springs, in others, it serves, itself, as the roll limiter, and still in another, the material is combined with a plurality of steel cylinders.

Description

BACKGROUND OF THE INVENTION

In my copending U.S. patent application Ser. No. 9,927 filed on Feb. 9, 1970, entitled ROLL LIMITER FOR RAILWAY CARS and assigned to the present assignee, I pointed out the importance of providing roll limiters with the capability of allowing relative motion, in a horizontal plane, between the car and its associated trucks. Because of the particular configurations described in my copending patent application, however, the roll limiters are required to be made of materials having extremely high impact strengths. That is, because the embodiments described in my copending patent application rely upon metal-to-metal contact to limit the roll of railway cars, the metallic elements must be of great strength lest they will shatter under the substantial impacts and loads exerted by the railway car. This, of course, increases the ultimate cost of the limiter.

SUMMARY OF THE INVENTION

The present invention relates to a simple but strong, reliable and yet relatively inexpensive roll limiter for positively defining a maximum angle through which a railway car is allowed to roll. At the same time, the limiter of the present invention permits free relative motion, in a horizontal plane, between the car and its associated trucks, this feature avoiding stress on the limiter when the car traverses curves. More specifically, the inventive device is constructed, in a certain embodiment, both of metallic members and of rubber-like members having exceptional strength characteristics and yet being quite resilient in nature. In other embodiments, only the rubber-like material is used. The particular resilient material employed in the present invention is produced by Disogren Industries of Manchester, New Hampshire, and the material is sold under the tradename of DISOGREN.

In one embodiment of the invention, the maximum roll angle is defined by a shock absorbing coil spring wound about a block of strong but yet resilient material, the material being positioned so as to separate each coil of the spring from its neighboring coils. In this way, metal-to-metal contact is avoided. In an alternate configuration of this embodiment, the shock absorbing coil spring is itself coated with the strong, resilient rubber-like material.

In a second embodiment, a block of the same rubber-like material discussed above serves, itself, as the roll limiter. Holes are drilled in the block of material to allow for free movement between the car and its trucks, or, alternatively, the entire central region of the block is removed.

In a third embodiment of the present invention, two blocks of strong and resilient material are separated from one another through the means of a plurality of steel cylinders. This assembly is held together as a single unit, is mounted on the truck of a railway car and serves as a positive roll limiter. The cylinders are allowed to roll and thus free movement between the car and its trucks is allowed. If desired, the last embodiment may be supplemented by the addition of shock absorbing coil springs for reducing the impact experienced by the blocks of the resilient material. Further, if desired, at least a portion of one of the blocks may be provided with holes, thereby increasing the resiliency of the block and thereby reducing the impact shock caused by the car.

Accordingly, it is the main object of the present invention to provide a strong and reliable device for positively limiting the roll of a railway car while allowing relative motion, in a horizontal plane, between the car and its associated trucks.

It is another object of the present invention to positively limit the roll of railway cars in a relatively inexpensive manner by employing a shock absorbing member of an extremely strong and yet resilient rubber-like material, with or without the addition of metallic support members.

These and other objects of the invention, as well as many of the attendant advantages thereof, will become more readily apparent when reference is made to the following description taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of the first embodiment of the present invention when mounted on one truck of a railway car;

FIG. 2 is a cross-section of the roll limiter embodied in FIG. 1;

FIG. 3 is an alternate configuration of the embodiment illustrated in FIGS. 1 and 2;

FIG. 4 is a cross-section of a second embodiment of the present invention;

FIG. 5 is an alternate configuration of the limiter illustrated in FIG. 4;

FIG. 6 is a cross-section of a third embodiment of the present invention; and

FIG. 7 is an alternate configuration of the limiter illustrated in FIG. 6.

DETAILED DESCRIPTION OF THE DRAWINGS

With reference to FIGS. 1 and 2, the first embodiment of the present invention will be described. A railway car 2 is shown mounted, in a conventional way, on a set of two trucks 3 (only one being shown). The roll limiter of the present invention is shown generally at 10, is adjustably mounted on one truck 4, and comprises, basically, a shock absorbing coil spring 12 surrounding a block of strong, resilient rubber-like material 14. The spring 12 and the material 14 are associated in such a manner that the material separates each coil of the spring 12 from its neighbor coils. An adjustable mounting plate 16 serves to mount the roll limiter on the truck 4 of the railway car 2, and an impact pad 18 defines the area which is to be contacted by the rolling car.

Due to resilience of the coil spring 12 and the block of material 14, the impact pad 18 is allowed to move, in a horizontal plane, relative to the mounting plate 16. In this manner, relative motion may take place between the car and its associated trucks even when the car, certain of its trucks, and the roll limiter are in direct contact. And, because the coils of the spring 12 are isolated from one another by means of the rubber-like material 14, the possibility of damage to the spring by metal-to-metal contact is avoided.

In FIG. 3, an alternate of the first embodiment of the present invention is shown. A shock absorbing coil spring 20 is coated with a layer of the strong but resilient rubber-like material described above. The material coating is shown at 22. A mounting plate 24 serves to couple the roll limiter to the associated truck of the car to be stabilized, and an impact pad 26 serves as a contact surface between the roll limiter and the rolling car.

In FIG. 4, the second embodiment of the present invention is illustrated. The roll limiter is shown generally at 30. In this embodiment, a block of the strong resilient rubber-like material 32 serves as the basic element in the roll limiter. A mounting plate 34 is provided to affix the limiter 30 to the appropriate truck of the railway car. The block of material 32 is provided with a plurality of holes 36 which may be molded into the material or, alternatively, may be drilled out of the material.

With the last described configuration, the above-noted disadvantages associated with metal-to-metal contact surfaces in reducing roll are avoided. The block of resilient material 32 serves the function of roll limiting. The holes 36 in the material 32 assist in this function in two ways. First, the holes 36 increase the resiliency of the material 32. In this manner, the material 32 reacts less to impact shocks, and the associated car is better cushioned from the point of view of cargo or passengers. And second, the provision of holes 36 makes it possible for the upper surface of the block of material 32 to move, in a horizontal plane, relative to the mounting plate 34. Therefore, the holes make it possible for the car to move freely with respect to its associated trucks, even when there is direct contact between the car, the limiter and the truck.

Under certain circumstances, the roll limiter may be designed using less material than the roll limiter shown in FIG. 4. When it is possible to so design the limiter, it may take the configuration illustrated in FIG. 5.

The limiter of FIG. 5 comprises a block of material 40 mounted on the truck of a railway car by means of a mounting plate 42. A portion of the block 40 is cut from the center, thus defining a hole 44. This limiter functions as does the limiter shown in FIG. 4 but is adapted for use when smaller impacts are expected.

Now, with reference to FIG. 6, the third embodiment of the present invention will be described. The roll limiter is shown generally at 50 and comprises, basically, a first block of strong, resilient rubber-like material 52, a second block of the same material 54, and a plurality of cylinders 56, as of steel, positioned between the first and second blocks 52 and 54. A pair of biasing springs 58 are provided to ensure unity between the blocks of resilient material and the steel cylinders. A mounting plate 60 serves to fasten the roll limiter 50 to a given truck of a railway car.

In operation, the limiter of FIG. 6 functions as follows. When the car contacts the upper block 54, during a straight-track roll cycle, the roll of the car is abruptly halted. When the car contacts the block 54 during a curve, the roll is again halted, but another motion is involved. The car attempts to move, in a horizontal plane, with respect to its trucks. With the present invention, the upper block 54 is allowed to roll along the cylinders 56, in a horizontal plane, and thus the car is allowed free horizontal movement with respect to its associated trucks.

To ensure that the steel cylinders 56 always return to a predetermined rest position with respect to the blocks 52 and 54, one of the blocks is provided with a number of cylindrical depressions 62 equal in number to the number of cylinders. In FIG. 6, the depressions 62 are provided in the lower block 52. Also, to allow free rolling motion between the cylinders 56 and the depressions 62, a non-stick plate 64 may be provided in the depressions 62. In this manner, free rotation of the cylinders 56 is permitted.

In the embodiment last described, the impact stress is take up by one member and relative motion between the car and the truck is ensured by another. That is, the impact of the railway car on the limiter 50 is taken up by the resilient blocks of material 52 and 54. The relative motion between the car and its associated trucks is, on the other hand, made possible by the interaction between the lower plate 52, cylinders 56 and the upper plate 54. When the car attempts to move horizontally with respect to its truck, the upper block 54 rolls along the top of the cylinders 56, the cylinders rotating without moving relative to the lower block 52, because of the non-stick plate 64. And, to bring the assembly back to its rest position when free from the influence of the car, the springs 58 are provided.

If it is discovered that a given railway car exerts an unusually high level of force on the roll limiter 50 (FIG. 6), means may be provided for cushioning the initial impact of the car and thus cushioning the forces exerted on the resilient members of the coupler. Such an embodiment will be described with reference to FIG. 7.

In FIG. 7, an alternate configuration of the limiter illustrated in FIG. 6 is shown generally at 70. The limiter 70 comprises a lower block of resilient material 72, an upper block of material 74, a plurality of steel cylinders 76 and a set of biasing springs 78. The assembly is mounted on a truck of a railway car by means of a mounting plate 80. Then, serving as initial shock absorbers, are a pair of coil springs 82 attached between the mounting plate 80 and an upper impact plate 84.

The operation of the roll limiter 70 of FIG. 7 is as follows. When the railway car contacts the impact plate 84, the shock absorbing coil springs 82 cushion the initial impact of the car. Then, through the means of the impact plate 84 and the resilient blocks 72 and 74, with their associated set of cylinders 76, the shock of the car is further cushioned. At the same time, a maximum allowable roll angle is defined. Horizontal movement between the car and its associated trucks takes place in a manner similar to that described with reference to FIG. 6.

If it is found that the limiter of FIG. 7, as described above, fails to adequately cushion the impact of the railway car, one of the blocks of resilient material may be provided with a plurality of holes 86. In FIG. 7, the holes 86 are shown in the block 74. These holes add to the resiliency of the upper block of resilient material and, in this manner, reduce the danger of damage to the resilient blocks and, at the same time, cushion the impact of the car from the standpoint of the cargo or from the standpoint of the passenger.

Above, there have been described several embodiments of the present invention, these embodiments being described only for the purpose of illustration. However, numerous equivalents may be embodied without departing from the spirit and scope of the present invention. It is the intent, therefore, that the present invention not be limited by the above but be limited only as defined in the appended claims.

Claims

I claim:

1. For use with a railway car provided with conventional trucks having track-engaging wheels for supporting the railway car and for guiding the same along a set of tracks, a roll limiting device for allowing the railway car to freely roll about a roll axis up to a predetermined roll angle and to then abruptly limit the roll to that angle, while allowing relative motion, in a horizontal plane, between the railway car and its trucks when the car traverses curves, the roll limiting device comprising: shock absorbing coil spring means; mounting means for attaching said spring means to a truck of a railway car; impact pad means associated with said spring means and serving to transmit forces from the rolling car to the spring means, said impact pad means being spaced from said railway car when the car is in repose so as to allow the car to freely roll up to said predetermined roll angle; and cushion means intermediate the individual coils of said spring means for isolating each coil from its neighboring coils, the roll limiting device being constructed in such a manner so as to approximate a substantially solid post-like structure when impacted by the rolling railway car while having the capability of allowing relative motion between the car and its trucks even when the car is in positive contact with the roll limiting device.

2. The device recited in claim 1, wherein said cushion means takes the form of a solid block of rubber-like material positioned within the body of said spring means and having thread-like extensions at the periphery thereof for mating with the coils of said spring means so as to isolate each coil from its neighboring coils.

3. The device defined in claim 1, wherein said cushion means takes the form of a rubber-like material coating each coil of said spring means so as to isolate each coil from its neighboring coils.

4. For use with a railway car provided with conventional trucks having track-engaging wheels for supporting the railway car and for guiding the same along a set of tracks, a roll limiting device for allowing the railway car to freely roll about a roll axis up to a predetermined roll angle and to then abruptly limit the roll to that angle, while allowing relative motion, in a horizontal plane, between the railway car and its trucks when the car traverses curves, the roll limiting device comprising: cushion means in the form of a block of strong, resilient rubber-like material, said cushion means being spaced from said railway car when the car is in repose so as to allow the car to freely roll up to said predetermined roll angle; mounting means for affixing said cushion means to a truck of a railway car; and at least one bore extending through the body of said cushion means, said at least one bore serving both to increase the resiliency of said block of material and to allow the surface of said material remote from said mounting means to move parallel to the surface of said material adjacent said mounting means, such parallel movement allowing the railway car to move, in a horizontal plane, relative to its trucks, even when the car is in positive contact with the roll limiting device.

5. The device described in claim 4, wherein a single relatively large bore is provided in the central region of said block of cushion material.

6. The device recited in claim 4, wherein a plurality of bores are scattered entirely throughout the body of said block of cushion material.

7. The device recited in claim 6, wherein said plurality of bores are of approximately the same diameter.

8. The device recited in claim 6, wherein said bores extend from one wall of said block to an opposite wall thereof and are oriented so as to extend parallel to the plane of the tracks and transverse to the direction of travel of the railway car.

9. For use with a railway car provided with conventional trucks having track-engaging wheels for supporting the railway car and for guiding the same along a set of tracks, a roll limiting device for allowing the railway car to freely roll about a roll axis up to a predetermined roll angle and to then abruptly limit the roll to that angle, while allowing relative motion, in a horizontal plane, between the railway car and its trucks when the car traverses curves, the roll limiting device comprising: a first block of resilient cushion material; a second block of resilient cushion material; mounting means for securing said first block of cushion material to the truck of a railway car; means for biasing said first and said second blocks of cushion material toward one another and into a predetermined rest position, with said rest position being such that said second block of cushion material is spaced from said railway car when the car is in repose so as to allow the car to freely roll up to said predetermined roll angle; and spacer means positioned between said first and said second blocks of resilient cushion material, said spacer means contacting only a portion of each of the adjacent surfaces of said blocks and serving both for spacing said blocks from one another and for allowing relative motion between said first and said second blocks of resilient cushion material.

10. The device recited in claim 9, wherein the adjacent surfaces of said first and said second blocks of resilient cushion material are planar.

11. The device described in claim 10, wherein said spacer means takes the form of a plurality of cylinders, the axis of each lying parallel to the planes of said first and said second blocks of resilient cushion material.

12. The device recited in claim 11, wherein the axis of each of said cylinders lies parallel to the plane of said tracks and transverse to the direction of travel of the railway car.

13. The device recited in claim 12, wherein said first block of resilient cushion material is provided with a plurality of depressions equal in number to the number of spacing cylinders, the shape and position of said depressions being such that each cylinder comfortably rests in a corresponding depression.

14. The device recited in claim 13, and further comprising: guide plate means intermediate each of said spacing cylinders and its associated depression for allowing free rotation of said cylinders and for preventing translation between said cylinders and said first block of resilient cushion material.

15. The device recited in claim 14, wherein said biasing means takes the form of a plurality of springs urging said first and said second blocks of resilient cushion material toward one another.

16. The device recited in claim 9, and further comprising: impact plate means associated with said second block of resilient cushion material on the side thereof remote from said spacer means; and shock absorber means for absorbing portions of the shocks developed by impact from the railway car, thus reducing the shocks experienced by said first and second blocks of cushion material.

17. The device recited in claim 16, wherein said shock absorbing means is in the form of at least two coil springs.

18. The device described in claim 17, wherein said second block of resilient cushion material is, at least in part, provided with a plurality of bores through the body thereof.

19. The device recited in claim 16, wherein the adjacent surfaces of said first and second blocks of resilient cushion material are planar; wherein said spacer means is in the form of a plurality of cylinders whose axes lie parallel to the plane of said tracks and transverse to the direction of travel of the railway car.

20. The device recited in claim 19, wherein said first block of resilient cushion material is provided with a plurality of depressions equal in number to the number of spacing cylinders, the shape and position of said depressions being such that each cylinder comfortably resides in one of said depressions.

21. The device recited in claim 20, and further comprising: guide plate means intermediate each cylinder and its associated depression, said guide plates allowing free rotation of said cylinders about their axes while preventing translation of said cylinders with respect to said first resilient cushion plate.