What is claimed is
1. In a railroad car, a center plate for a body bolster and center sill assembly comprising:
2. The invention according to claim 1, and
3. The invention according to claim 2, and
4. The invention according to claim 2, and
5. The invention according to claim 2, and
6. The invention according to claim 2, and
7. The invention according to claim 6, and
8. In a railroad car, a center plate and body bolster and center sill assembly comprising:
9. The invention according to claim 8, and
10. The invention according to claim 8, and
11. The invention according to claim 8, and said center plate including:
12. The invention according to claim 8, and
13. The invention according to claim 8, and
The present invention relates to railroad car underframe construction and more particularly to an improved construction of a bolster body center plate assembly for a cushioned underframe railroad car.
Railroad rolling stock are required to carry very large loads today in modern oversize cars and, consequently, the body bolster center plate assembly is subject to very high stresses. These stresses are most high when the car sways laterally about its longitudinal axis or from side to side in a "rock and roll" fashion. The high stresses are developed in the lateral end portions of the center plate. Where the lateral end portions of the center plate are not flat in horizontal plane but are angulated it is difficult to get a close fit between the angulated lateral end portions of the center plate and the angulated portions of the bolster arrangement so that when the center plate is attached to the bolster, as by bolting down, a close flush fit between the bolster and the center plate is extremely difficult with resultant high stresses developing when the bolts are securely fastened for attaching the cover plate and bolster together. These stresses, of course, are very highly undesirable and affect the life of the center plate.
It is, therefore, a general object of this invention to provide for flat lateral end portions for the center plate which, in turn, are attached to flat lateral underside portions of the underframe to insure a good fitting relation without being concerned about any tolerances between the bolster and the center plate and to insure a flat flush engagement between each part with resultant low stress level developed in the bolster when subject to "rock and roll" conditions in travel.
Another object of this invention is to provide for a body bolster center plate arrangement provided with securing means in the form of a pair of rows of bolts fixedly attaching each lateral flat horizontal end portion of the center plate to the flat horizontal lateral end portion of the bolster structure on each side of the sliding sill structure of the cushioned underframe. The outer row of bolts attach on each bolster side the outer part of the flat horizontal lateral end portion of the center plate to the flat horizontal portion of the bottom cover plate of the bolster and the other associated row of bolts attach on each bolster side the respective channel section of the fixed center sill, the bottom cover plate portion of the bolster structure, and the inner part of the flat horizontal lateral end portion of the cover plate together.
It is another object of this invention to provide for a body bolster center plate assembly wherein the cover plate structure is a one-piece integral structure comprising an intermediate horizontal mounting plate portion having thereon an upper center filler portion with a pair of longitudinally extending reinforcing vertically upwardly extending elements and within the sliding center sill portion and a depending lower pair of reinforcing elements underneath the mounting plate portion and extending transversely and on each side and longitudinally spaced of the center plate, each depending element including a pair of downward depending transversely extending supporting reinforcing members, said central horizontal flat mounting plate portion carrying the upper and lower reinforcing elements and laterally spaced fore and aft pairs of elongated longitudinally extending wear pads for the sliding sill, said mounting plate portion having lateral apertured areas to define two forward and two aft flat central tab or coped out portions, each tab portion having apertures for receiving bolt means for attaching each of the flat horizontal tab portions to the flat underside portion of the bolster structure, a central depressed apertured bearing or body bowl portion, and longitudinally spaced upright cross supporting portions on either side of the center bearing portion and connecting with the longitudinally extending upright reinforcing elements to define therewith the rectangular reinforcing center filler structure for the kingpin receiving apertured bowl portion.
Another object of this invention is to provide for bolster reinforcing gusset structures for each lateral bolster portion on opposite lateral sides of the center plate structure.
Another object of the invention is to provide for adapter flat bolster surface means for receiving the flat portions of the cover plate.
Still another object is to provide cope area at the lateral sides of the cover plate to define bolster securing tab portions, the purpose of the cope being to reduce the stress at the radius of the juncture between the bowl or central bearing portion and the body plate or flat attaching portion in transverse direction to the longitudinal axis of the car.
A further object is to provide means for supporting the kingpin of a railroad truck in the center plate construction.
These and other objects will become apparent from reference to the following description, attached drawings and appended claims, to wit:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the novel and inventive body bolster center plate arrangement;
FIG. 2 is a top perspective view of the center plate structure;
FIG. 3 is a bottom perspective view of the center plate structure;
FIG. 4 is a plan view of a modified form bolster construction of my body bolster center plate arrangement;
FIG. 5 is an end elevational view of the bolster construction of the bolster body center plate arrangement shown in FIG. 4;
FIG. 6 is a schematic view illustrating coupling together of a wing-type cover plate to a body bolster to illustrate tolerance problems between the body bolster and the cover plate;
FIG. 7A is a schematic view illustrating the use of a single bolt connection between the fixed center sill and the center plate;
FIG. 7B is a schematic view illustrating the use of the two-bolt arrangement between the center sill, the center plate and the bottom cover plate of the bolster; and
FIG. 8 is a view of a modified center filler portion and bowl construction of the center plate.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to the drawings for a more complete understanding of the present invention, there is shown in FIG. 1 a portion of a cushioned underframe 1 to which the structure of the present invention may be applied. As usual, the cushioned underframe 1 comprises a plurality of structural steel elements that are welded or riveted together to produce a complete underframe. The cushioned underframe 1 of the railroad car includes a center sill 2 and a body bolster 3 extending therefrom at each end of the car. Fixed adjacent to the body bolster for mounting the conventional truck bolster thereon is a center plate structure 4 embodying the principles of the present invention in conjunction with the bolster structure 3. Slidably disposed within the center sill 2 for lengthwise movement thereof is a sliding sill 5 limiting this lengthwise movement of the cushion unit (not shown) which is arranged in the conventional manner for interaction between the center sill 2 and the sliding sill 5 to reduce the force of impact applied at the couplers (not shown).
The center sill 2 comprises a pair of laterally spaced longitudinally extending channel sections 6 and 7 that extend lengthwise of the car on opposite sides of the sliding sill 5. Each channel section 6 or 7 comprises upper and lower outwardly laterally directed flanges 9 and 10 connected by a vertical web 11.
The sliding sill, disposed between each channel section 6 and 7, is an upright hat-shaped section having lower horizontal laterally outwardly directed flanges 12 and 13, upright vertical web portions 14 and 15, and top connecting web section 16.
The bolster structure 3 comprises an upper or top flat horizontal transversely extending plate 16a which is fixedly attached to the channel sections 6 and 7 of the center sill and is located over the top plate 16 of the sliding sill 5. The bolster 3 also comprises a transverse two separate pieced bottom plate structure 17 including transverse lateral sections 17a, 17b underneath and in alignment with the top plate 16. Each bottom plate section 17a or 17b is laterally spaced apart from the other plate section 17b or 17a and includes a horizontal plate portion 18 spanning between each channel section 6 and 7 of the center sill 2, and an upwardly sloped lateral plate portion 19 at each outer end of a flat plate portion 18 and an outwardly directed lateral end portion 20 connected to the outer end of each slope or divergent portion 19, the portions 20 extending to the side sills (not shown) of the car in the usual manner. The upper and lower plate portions 16a and 17 are connected by transversely extending upright outer vertical web sections 21 and 22 at each lateral side which extend inwardly to the outwardly facing surface of a respective channel section 6 or 7, that is, to a respective web 11. An I-beam stringer section 22a extends on each side of the transverse bolster 3 and at each lateral end of the bolster 16 to comprise four such stringer structures 22a which terminate at a respective web section 21 or 22 and are attached thereto and to the top plate 16a. Laterally spaced diagonal inwardly upwardly directed reinforcing gussets 23 extend up from the juncture of the lower end plate portion 20 with the slope lower plate portion 19 on each side of the bolster structure and connect with the underside of the respective of each of the four stringer structures 22a. An additional upright or vertical gusset 24 extends between the juncture of the lower slope plate portion 19 and each middle horizontal plate 18 on each lateral side of the bolster 3 and extends up to the top bolster plate 16a and is welded therewith as indicated by welding W.
The center plate structure 4 is fastened to the underside of each flat horizontal plate portion 18 of the lower cover plate 17 by two rows of two bolt means each on each side of each upright transverse web 21 or 22 and on each side of channel section 6 or 7, as shown for instance in FIG. 4 of a modified form of the bolster structure. However, in the modified form of the bolster structure or in the form shown in FIG. 1, the bolt arrangement of the bolt means 25 is the same. Each bolt means or securing means 25 comprises an upper bolt element 25a and a lower nut 25b.
The construction of the center plate structure 4 shown is of an integral or unit cast or forged structure although it is appreciated that the various parts may be welded together into an integral form also. The cover plate structure comprises, as best seen in FIGS. 6 and 7, a flat horizontal intermediate portion or mounting plate portion 26 having a downwardly extending center plate bowl portion 27 for resting on the trucks (not shown) of the railroad car and including a central kingpin receiving aperture 28. The central bearing plate portion or bowl portion 27 is surrounded on the top of the plate portion 26 below which it is depressed, by a center filler portion 27a including a pair of longitudinally spaced transverse reinforcing ribs 29 and 30 and by a pair of longitudinally extending upright reinforcing elements 31 and 32 on mounting plate portion 26 which have their outer longitudinal fore and aft top surfaces tapered downwardly outwardly of the filler portion but their intermediate surfaces generally horizontal and connecting with the transverse rib portion 29 and 30 to define the filler portion. Atop each laterally outwardly directed part of the mounting plate portion 26 is a pair of longitudinally spaced upright elongated wear pad parts 33 and 34 that are laterally outward of the center filler portion 27a for sliding of the sliding sill 5 relative to the fixed center plate structure 4. The flat mounting plate portion 26 in plan view appears as a plurality of symmetrically placed tab portions 26a defined by a recessed or scalloped portion or cope 26b on each lateral side of the center mounting plate portion to provide an open space 26c on each lateral side of the cover plate structure. Depending from the underside of the mounting plate portion 26 is a pair of elongated transversely extending reinforcing structures 40 on either side of the depending bowl portion 27. Each underside reinforcing structure 40 comprises a pair of transversely extending ribs 30a which extend approximately the full length of the width of the central mounting plate 26 into the tab sections 26a thereof and, therefore, pass under the upper reinforcing members 31 extending upwardly from the top surface of the plate portion 26. The members 30a have a flat horizontal center edge and a sloping edge at each end thereof similar to the construction of the reinforcing members 31 and 32. Each of the tab portions 26a are provided with four bolt-receiving apertures 42 each for receiving a respective bolt means 25. In the assembled condition, the upper reinforcing elements 31 and 32 extend longitudinally of the car in between the sliding center sill 5 as shown in FIG. 1.
It will be noted that in FIG. 1 each of the laterally outward row of bolts fasten a respective end of mounting plate portion 26 to the top flat surface of each flat section 18 of each bolster web portion 17a or 17b and each inner row of bolts attach the lower horizontal flange 10 of each center sill channel section 6 or 7, the flange 18 of each respective bolster web section 17a or 17b and a respective pair of longitudinally aligned tabs 26a together. Whereas in the modification shown in FIGS. 4 and 5 wedges or sloped upper and lower spacer blocks 35 and 36 are placed on the sloped portion 37 of the bolster construction 3' since the portion 37 slopes upwardly as distinguished from the horizontal section 18 in FIG. 1 which does not. Thus, in the modification shown in FIGS. 4 and 5, the flat portion or mounting plate portion 26 can be mounted to the conventional construction of a bolster web 3'. With that exception and with the exception of a different bolster reinforcing gusset arrangement where there is provided just one upright reinforcing gusset means 38 at each bolster section, the construction of the embodiment shown in FIG. 1 is the same as the construction of the embodiment shown in FIGS. 4 and 5.
Thus, what is provided here is a center plate arrangement for a cushioned underframe car where the center plate construction 4 is a single integral forging or cast but may be in sections held together by welding. The center plate construction is provided with upper flat horizontal terminal surfaces on opposite sides thereof and received in complemental opposed relation with the flat underside surfaces of the car bolster, such center plate and bolster arrangement 3 being at each end of the car for being supported by respective truck arrangements. The center plate is secured to the car body bolster by the double rows of bolts 25 on each side of the center sill structure, one of the rows of bolts being secured to the bottom center sill flange and the second row of such bolts being secured to the bolster outwardly of the center sill flange.
FIG. 6 is illustrative of the "wing" type of center plate construction where the lateral ends E of the center plate C are bent up and diagonally outward and such a construction creates dimensional tolerance problems when fitted against the underside of a similarly formed bottom bolster plate arrangement B, as shown, and wherein bolt means b go into the diagonal flat section of the bolster and center plate as well as the horizontal flat portions of the bolster and center plate. Torquing of the bolts b in such a construction causes stress problems in these areas of the center plate and bolster. Further, the inventive construction of having flat portions 26a at the terminal lateral ends of the center plate 4 eliminates such stress problems and the novel arrangement of a double row of bolts 25 on each lateral side of the center plate connecting it with the bolster 3 provides sufficient length of surface contact between the bolster and the end portions or tabs 26a of the center plate, eliminating any gap between the lateral ends of the center plate and the bolster. Also less deflection of the bolster under "rock and roll" of the car body relative to the trucks occurs when the double set of bolts are used. Both the problem of gapping and of deflection are illustrated in FIGS. 7A and 7B. In FIG. 7A because of the use of a single bolt, a gap G is produced between the bolster web portion 17a or 17b and the end of the center plate 4. Such a gap condition does not exist in FIG. 7B because sufficient length of both the bolster and lateral end of the center plate are held together by the double set or row of bolts, that is, there is enough length of contact between flats of center plate and bolster to resist a bending moment at the joint or bolted area. FIGS. 7A and 7B are illustrative of a "rock and roll" condition where the car is tending to rock counterclockwise as viewed in these pictures. It is further noted that the deflection D1 of the bolster is a greater distance in FIG. 7A where only one bolt is used than the deflection D2 as shown in FIG. 7B where the two-bolt construction for connecting each lateral side of the bolster center plate arrangement is illustrated. The greater the gapping, the greater is the stress or higher is the tensile force on the bolt and the poorer is moment of resistance of the bolt so the bolt will fracture more readily. The greater the deflection of bolster the higher the stress on the bolster and on the center plate and, therefore, the greater is the chance of fracturing or damage to the bolster and center plate parts. Where there is no gap there is a low tensile force on the bolts and a good moment of resistance at the bolts.
The center plate arrangement is provided with the deeply cut-in areas of the base plate mounting plate portion to provide the copes 26b at the two lateral sides for stress distribution. The copes 26b define the tabs 26a into which extend the underside transverse reinforcing members so that loads and stress distribution occurs longitudinally along the upper reinforcing elements and transversely along the lower reinforcing elements into the tab areas, there being less stresses set up between the juncture of the bowl with the mounting plate portion because of the cutout or cope portions 26b. That is, the copes 26b reduce the stresses at the radius of juncture between the bowl and the body mounting plate portion by preventing stress travel in a transverse direction. The copes 26b force the loads on the center plate structure to go a preferred path so as to reduce the stresses at the radius of the bowl with the mounting plate portion and the preferable path will be such that the forces will be transmitted along the longitudinal upright reinforcing members on top of the mounting plate and along the lower or depending reinforcing members underneath the mounting plate portion.
FIG. 8 shows a modified form of a bowl which is filled with material and is provided with a truck kingpin receiving aperture 50 vertically the extent of the filled in area 51 to lend sufficient support for the truck kingpin. The center filler portion of either the construction shown in FIG. 1 or in FIG. 8 is otherwise a box or rectangular structure which adds additional strength to the center plate construction, the longitudinally extending portions thereof having extensions forming the upper reinforcing elements of the cover plate.
The foregoing description and drawings are given merely to explain and illustrate the invention, and the invention is not to be limited thereto since those skilled in the art who have the disclosure before them will be able to make modifications and variations therein without departing from the scope of the invention.