Railcar truck

Description

Background of the Invention

[0001] The present invention is directed to a railcar truck, and in particular to a railcar truck having a side frame pedestal including a cast iron wear plate adapted to engage a friction wedge and a saddle having an adjustable and removable rocker member and a removable link arm.

[0002] Railcar trucks include a pair of spaced apart generally parallel side frames connected by a transverse bolster. Bach side frame includes a pedestal at each end that is adapted to be connected by a saddle to a wheel set. A plurality of springs extend between the saddle and the side frame such that the side frame is resiliently supported on the saddle. Friction wedges are disposed between the saddle and the side frame to dampen vertical, lateral and longitudinal movement of the side frame with respect to the saddle.

[0003] An example of a rail car truck having a sides frames with pedestals at each end that is adapted to be connected by a saddle to a wheel set is discloses in US 3,394,662.

[0004] US 5,450,799 discloses an alternative truck pedestal design.

Summary of Invention

[0005] According to the invention there is provided a pedestal of a side frame for a railcar truck as described in the accompanying claims.

[0006] There is also provided a saddle and pedestal assembly as further described in claim 7.

[0007] An embodiment of the invention comprises a pedestal of a side frame for a railcar truck having a first and second friction wedge in which the pedestal includes a first pedestal jaw having a first interior face and a second pedestal jaw including a second interior face. A first wear member is attached to the first face of the pedestal jaw and includes a front friction surface adapted to engage a first friction wedge. A second wear member is attached to the second face of the second pedestal jaw and includes a front friction surface adapted to engage a second friction wedge. The first wear member and the second wear member are formed from the material having a kinetic coefficient of friction with steel of approximately 0.15 such as cast iron.

Brief Description of the Drawing Figures

[0008] 

Figure 1 is a partial cross sectional view of a rail car truck of the present invention.

Figure 2 is a front view of the wear member of the pedestal of the truck side frame.

Figure 3 is a side elevational view of the wear member taken along line 3-3 of Figure 2.

Figure 4 is a partial cross-sectional view of the saddle of the railcar truck show with a shim.

Figure 5 is a top plan view of the saddle of the railcar truck.

Figure 6 is a partial cross-sectional side view of the saddle with the shim removed.

Figure 7 is a cross-sectional view taken along line 7-7 of Figure 6.

Detailed Description of the Preferred Embodiment

[0009] The railcar truck 20 as shown in Figure 1 includes a pair of spaced apart and generally parallel side frames 22 (only one shown). The side frames 22 arc connected to one another by a transverse bolster (not shown). Each side frame 22 includes a pedestal 24 at each end. The pedestal 24 includes a first pedestal jaw 26 and a second pedestal jaw 28. A pedestal cavity 30 is formed between the first and second pedestal jews 26 and 28. The first pedestal jew 26 includes an inclined face 32 and the second pedestal jaw 28 includes an inclined face 34.

[0010] A saddle 35 is adapted to be located within the pedestal cavity 30. A plurality of resilient coil springs 36 extend between the saddle 35 and the pedestal 24 such that the pedestal 24 is resiliently supported by the springs 36. A bearing 37 and an axle 38 of a wheel set is coupled to the saddle 35 such that the axle 38 is rotatable with respect to the saddle 35. A plurality of friction wedges 39 having wear surfaces formed of composite material and steel or acicular iron, are resiliently biased by one or more springs 36 into engagement with the pedestal 24 and the saddle 35 to dampen vertical movement of the pedestal 24 with respect to the saddle 35.

[0011] A wear member 40 is removably attached to the inside surface the inclined face 32 of the first pedestal jaw 28 and a wear member 40 is also attached to the inside surface of the inclined face 34 of the second pedestal jaw 28. The wear member 40, as best shown in Figure 2, includes a generally rectangular wear plate 42 having a top edge 44, a bottom edge 46, and spaced apart and generally parallel first and second side edges 48 and 50 which extend between the top and bottom edges 44 and 46. The wear plate 42 includes a generally planar front friction surface 52 and a generally planar rear surface 54 which is generally parallel to the friction surface 52. The wear plate 42 includes one or more apertures 56 which may be conical or countersunk. The wear plate 42 is preferably formed from cast iron which has a kinetic coefficient of friction with steel or acicular iron of approximately 0.15.

[0012] The wear member 40 also includes a backing member 60 which may be attached to the rear surface 54 of the wear plate 42 by an adhesive or the like. The backing member 60 extends generally coextensively with the rear surface 54. The backing member 60 is preferably formed from a sheet of polytetrafluoroethylene (PTFE) that is approximately one millimeter thick. The backing member 60 includes an exterior surface 62 and one or more apertures 64 which are respectively aligned with the apertures 56 in the wear plate 42. The backing member 60 is adapted to be placed adjacent the inclined face 32 or 34 of the pedestal 24 to accommodate any surface irregularities in the cast surface of the inclined faces 32 and 34 thereby providing a good mating fit between the rear surface 54 of the wear plates 42 and the inclined faces 32 and 34. The backing member 60 reduces or dampens any noise that may otherwise be produced between the fit of the wear plate 42 with the pedestal 24.

[0013] Forming the wear plate 42 from cast iron which has a kinetic coefficient of friction with the steel or acicular iron of the friction wedge 39 of approximately 0.15, as opposed to forming the wear plate 42 from steel which has a kinetic coefficient of friction with the steel or acicular iron of the friction wedge 39 of approximately 0.30, promotes generation of a lower axle centering force. Axle centering forces act horizontally toward the center of the axle at curves in the railroad track and are generated by surface forces between the friction wedge 39 and the wear member 40. When the axle centering force can be decreased, the forces generated at the wheel/rail interface that are needed to move the axle are also lower and self-steering of the wheel is promoted. Lower self-steering forces are particularly required at laden. High resistance to self-steering can be caused by use of steel wear plates. In addition, wear plate 42 from cast iron has a better damping capacity than a steel wear plate, making the suspension less prone to generating noise.

[0014] The saddle 3 5 of the railcar truck 20 as best shown in Figure 4 extends between a first end 70 and a second end 72. The saddle 35 includes a center post 74 having a generally horizontal roof 76, a first side wall 78 that extends downwardly from the roof 76 to a bottom end 80, and a second side wall 82 that extends downwardly from the roof 76 to a bottom end 84. The second side wall 82 is spaced apart from the first side wall 78 and a cavity 86 is formed therebetween. A horizontal first shelf 88 extends outwardly from the bottom end 80 of the first side wall 78 to the first end 70 of the saddle 35. A horizontal second shelf 90 extends outwardly from the bottom end 84 to the second end 72 of the saddle 35. Each shelf 88 and 90 is adapted to engage and support the bottom end of a spring 36 as shown in Figure 1. The roof 76 includes a roof cavity 92 that is in communication with the cavity 86.

[0015] As best shown in Figures 4, 6 and 7, the bottom end 80 of the first side wall 78 includes a pocket 94 and the bottom end 84 of the second side wall 82 includes a pocket 95. Each pocket 94 and 95 includes a vertical and generally planar rear wall 96, a horizontal and generally planar top wall 98, a vertical generally planar first side wall 100, and a vertical and generally planar second side wall 102. The first side wall 100 is spaced apart from and is generally parallel to the second side wall 102. The pockets 94 and 95 are in communication with the cavity 86. Each pocket 94 and 95 is open at its bottom end that opposes ita top wall 98. The first pocket 94 forms a pair of opposing wing members 104 at the bottom end 80 of the first side wall 78 on each side of the pocket 94. The second pocket 95 forms a pair of opposing wing members 106 on each side of the pocket 95 at the bottom end 84 of the second side wall 82. A threaded bore 108 extends vertically upwardly through the top wall 98 of the pocket 94 into the first side wall 78. A threaded bore 110 extends vertically upwardly through the top wall 98 of the pocket 95 into the second side wall 82.

[0016] The saddle 35 includes a selectively removable link member 120. The link member 120 extends generally linearly between a first end 122 and a second end 124. The first end 122 includes an aperture 126 and the second end 124 includes an aperture 127. The first end 122, as best shown in Figure 6, includes a generally vertical and planar end wall 128 which is adapted to engage the rear wall 96 of the first pocket 94 of the first side wall 78. The first end 122 of the link member 120 also includes a generally horizontal and planar top wall 130 that is adapted to engage the top wall 98 of the first pocket 94 of the first side wall 78. The second end 124 of the link member 120, as best shown in Figure 4, includes a vertical and generally planar end wall 132 that is adapted to engage the rear wall 96 of the second pocket 95 of the second side wall 82. The second end 124 of the link member 120 also includes a horizontal and generally planar top wall 134 which is adapted to engage the top wall 98 of the second pocket 95. As best shown in Figure 7, the center portion of the link member 120 is generally I-shaped.

[0017] The first end 122 of the link member 120 is inserted into the first pocket 94 of the first side wall 78 of the saddle 35 such that the end wall 128 engages the rear wall 96 of the first pocket 94, and such that the vertical aperture 126 is aligned with the aperture 108 in the top wall 98 of the pocket 94. A fastener 136 such as a bolt is inserted through the first end 122 of the link member 120 into the saddle bore 108 of the top wall 98. The second end 124 of the link member 120 is inserted into the second pocket 95 of the second side wall 82 of the saddle 35 such that the end wall 132 engages the rear wall 96 of the second pocket 95. The vertical aperture 127 at the second end 124 of the link member 120 is aligned with the bore 110 in the top wall 98 of the second pocket 95 and a fastener 138 is placed therethrough

[0018] The length of the link member 120 between the end walls 128 and 132 is such that the link member 120 will closely fit between and mate with the rear walls 96 of the first pocket 94 and second pocket 95 due to use of an interference fit. The link member 120 is placed in compression during operation by the loads that are applied from the springs 36 to the shelves 88 and 90 of the saddle 35. The fasteners 136 and 138 do not act to transfer any shear load or shear force between the link member 120 and the first and second side walls 78 and 82 of the saddle 35. The loads from the first and second side walls 78 and 82 are transferred to the link member 120 by engagement with the end walls 128 and 132 of the link member 120. The fasteners 136 and 138 are tightened in order to apply a compression frustrum between the end of the link member 120 and the top walls 98 of the pockets 94 and 95 of the saddle 35. Hence the link member 120 is held in contact with the saddle pockets at all times on walls 96 and 98 of pockets 94 and 95 of saddle 35.

[0019] The link member 120 facilitates easy maintenance of the railcar truck 20. In order to remove the saddle 3 5 from the wheel set, the fasteners 13 6 and 13 8 are removed, and then the link member 120 is removed from the saddle 35. This is done by use of an expansion tool acting between the side walls 78 and 82, such that the pocket rear walls 96 are moved apart in order to negate the interference fit of the ends of the link member 120 over walls 128 and 132. Once the link member 120 is removed, the saddle 35, springs 36, and side frame 22 may then be lifted upwardly away from the wheel set to enable the performance of maintenance. The saddle 35, springs 36, and side frame 22 are held together during lifting by retaining studs 142.

[0020] As shown in Figure 1, the saddle 35 is supported on the bearing 37 and axle 38 of the wheel set by a rocker member 150. The rocker member 150 includes a top wall 152 which is generally planar and which is adapted to be inserted into the roof cavity 92 of the roof 76 of the saddle 35. The rocker member 150 also includes a bottom wall 154 which is adapted to engage the bearing 37. The rocker member 150 includes a plurality of threaded bores which extend into the rocker member 150 through the top wall 152. A backing member 158 is placed between the rocker member 150 and the roof 76 of the saddle 35 within the roof cavity 92 to accommodate any cast or forged surface irregularities in the surface of the roof 76. The backing member 158 is preferably a sheet of PTFE approximately one millimeter thick. The backing member 158 also reduces or dampens noise which may otherwise be created between the rocker member 150 and the saddle 35. The rocker member 150 is removably attached to the roof 76 of the saddle 35 by a plurality of threaded fasteners 160 which extend through apertures in the roof 76 and which threadably engage the bores 156 in the rocker member 150.

[0021] The mechanical attachment of the rocker member 150 to the roof 76 of the saddle 35 by the fasteners 160 enables the rocker member 150 to be easily and quickly replaced if the rocker member becomes worn or damaged. In addition, as shown in Figure 4, the mechanical attachment of the rocker member 150 to the roof 76 also enables, when desired, a shim 162 to be placed between the top wall 152 of the rocker member 150 and the backing member 158 that is located within the roof cavity 92 of the roof 76. The shim 162 includes a plurality of apertures through which the fasteners 160 may extend from the roof 76 into the bores 156 of the rocker member 150. The shim 162 includes a top wall 164 that is adapted to engage the backing member 158 and a bottom wall 166 that is adapted to engage the top wall 152 of the rocker member 150. The shim 162 may have a thickness of up to approximately eighteen to twenty millimeters between the top wall 164 and the bottom wall 166. The ability to place a shim 162 of a desired thickness between the rocker member 150 and the backing member 158 in the roof 76 enables the saddle 35 and its adjoining parts to be height adjusted to accommodate excessive wheel wear and spring vertical movement that otherwise would cause the car body buffer centers go out of gauge tolerance.

[0022] Various features ofthe invention have been particularly shown and described in connection with the illustrated embodiments of the invention, however, it must be understood that these particular arrangements merely illustrate, and that the invention is to be given its fullest interpretation within the terms of the appended claims.

Claims

1. A pedestal (24) of a side frame (22) for a railcar truck (20) having a first friction wedge (39) and a second friction wedge (39), said pedestal (24) including:

a first pedestal jaw (26) including a first interior face (32);

a second pedestal jaw (28) including a second interior face (34);

a first wear member (40) having a front friction surface (52) and being adapted to be engaged between the first face (32) of said first pedestal jaw (26) and the first friction wedge (39);

a second wear member (40) having a front friction surface (52) and being adapted to be engaged between the second face (34) of said second pedestal jaw (28) and the second friction wedge (40);

characterized in that said first wear member (40) and said second wear member (40) are formed from a material having a kinetic coefficient of friction with steel or acicular iron of approximately 0.15.

2. The pedestal (24) of claim 1 wherein said material having a kinetic coefficient of friction with steel or acicular iron of approximately 0.15 comprises cast iron.

3. The pedestal (24) of claim 1 or 2 including a backing member (60) located between said first wear member (40) and said first face (32) of said first pedestal jaw (26).

4. The pedestal (24) of claim 3 wherein said backing member (60) comprises a sheet of polytetrafluoroethylene.

5. The pedestal (24) of any preceding claim in which the first wear member (40) is attached to said first face (32) of said first pedestal jaw (26) with the front friction surface (52) of the first wear member (40) is adapted to engage the first friction wedge (39), and in which the second wear member (40) is attached to said second face (34) of said second pedestal jaw (28) with the front friction surface (52) of the second wear member (40) adapted to engage the second friction wedge (39).

6. The pedestal (24) of any preceding claim in which the first (32) and second (34) interior faces are inclined faces.

7. A saddle (35) and pedestal (24) assembly for a rail car truck (20) adapted to receive a bearing (37) and wheel axle (38), the assembly comprising:-

a pedestal (24) of any one of claims 1 to 5, in which the first (26) and second (28) pedestal jaws define a pedestal cavity (30);

a saddle (35) which is adapted to be located within the pedestal cavity (3 0), the saddle (3 5) being adapted to be coupled to the bearing (37) and wheel axle (38);

a first friction wedge (3 9) resiliently biased into engagement between the first pedestal jaw (26) and the saddle (35); and

a second friction wedge (39) resiliently biased into engagement between the second pedestal jaw (28) and the saddle (35).

Ansprüche

1. Achshalter (24) eines Seitenträgers für ein Triebwagen-Drehgestell (20) mit einem ersten Reibkeil (39) und einem zweiten Reibkeil (39), wobei der Achshalter (24) enthält:

eine erste Achshalterbacke (26), die eine erste Innenfläche (32) enthält;

eine zweite Achshalterbacke (28), die eine zweite Innenfläche (34) enthält;

ein erstes Verschleißelement (40), das eine vordere Reibfläche (52) hat und so eingerichtet ist, dass es zwischen der ersten Fläche (32) der ersten Achshalterbacke (26) und dem ersten Reibkeil (39) in Eingriff kommt;

ein zweites verschleißelement (40), das eine vordere Reibfläche (52) hat und so eingerichtet ist, dass es zwischen der zweiten Fläche (34) der zweiten Achshalterbacke (28) und dem zweiten Reibkeil (40) In Eingriff kommt;

dadurch gekennzeichnet, dass das erste Verschleißelement (40) und das zweite Verschleißelement (40) aus einem Material bestehen, das einen kinetischen Reibungskoeffizienten von ungefähr 0,15 mit Stahl oder Eisen mit Nadelgefüge hat.

2. Achshalter (24) nach Anspruch 1, wobei das Material, das einen kinetischen Reibungskoeffizienten von ungefähr 0,15 mit Stahl oder Eisen mit Nadelgefüge hat, Gusseisen umfasst.

3. Achshalter (24) nach Anspruch 1 oder 2, das ein Trägerelement (60) enthält, das sich zwischen dem ersten Verschleißelement (40) und der ersten Fläche (32) der ersten Achshalterbacke (26) befindet.

4. Achshalter (24) nach Anspruch 3, wobei das Trägerelement (60) eine Lage aus Polytetrafluoräthylen umfasst.

5. Achshalter (24) nach einem der vorangehenden Ansprüche, wobei das erste Verschleißelement (40) an der ersten Fläche (32) der ersten Achshalterbacke (26) angebracht ist, die vordere Reibfläche (52) des ersten Verschleißelementes (40) so eingerichtet ist, dass sie mit dem ersten Reibkeil (39) in Eingriff kommt, das zweite Verschleißelement (40) an der zweiten Fläche (34) der zweiten Achshalterbacke (28) angebracht ist und die vordere Reibfläche (52) des zweiten Verschlelßelementes (40) so eingerichtet ist, dass sie mit dem zweiten Reibkeil (39) in Eingriff kommt.

6. Achshalter (24) nach einem der vorangehenden Ansprüche, wobei die erste (32) und der zweite (34) Innenfläche geneigte Flächen sind.

7. Baugruppe aus Sattel (35) und Achshalter (24) für ein Triebwagen-Drehgestell (20), die so eingerichtet ist, dass sie ein Lager (37) und eine Radachse (38) auf nimmt, wobei die Baugruppe umfasst:

einen Achshalter (24) nach einem der Ansprüche 1 bis 5, wobei die erste (26) und die zweite (28) Achshalterbacke einen Achshalter-Hohlraum (30) bilden,

einen Sattel (35), der so eingerichtet ist, dass er in dem Achshalter-Hohlraum (30) angeordnet ist, wobei der Sattel (35) so eingerichtet ist, dass er mit dem Lager (37) und der Radachse (38) gekoppelt wird;

einen ersten Reibkeil (39), der elastisch in Eingriff zwischen der ersten Achshalterbacke (26) und dem Sattel (35) gespannt wird; und

einen zweiten Reibkeil (39), der elastisch in Eingriff zwischen der zweiten Achshalterbacke (28) und dem Sattel (35) gespannt wird.

Revendications

1. Socle (24) de cadre latéral (22) destiné à un bogie pour un véhicule ferroviaire (20) ayant une première cale de frottement (39) et une seconde cale de frottement (39), ledit socle (24) comprenant :

une première mâchoire de socle (26) comprenant une première face intérieure (32) ;

une seconde mâchoire de socle (28) comprenant une seconde face intérieure (34) ;

un premier élément d'usure (40) disposant d'une surface de frottement avant (52) et étant adapté pour venir en prise entre la première face (32) de ladite première mâchoire de socle (26) et la première cale de frottement (39) ;

un second élément d'usure (40) disposant d'une surface de frottement avant (52) et étant adapté pour venir en prise entre la seconde face (34) de ladite seconde mâchoire de socle (28) et la seconde cale de frottement (40) ;

caractérisé en ce que ledit premier élément d'usure (40) et ledit second élément d'usure (40) sont formés d'un matériau ayant un coefficient de frottement dynamique avec de l'acier ou du fer aciculaire d'environ 0,15.

2. Socle (24) selon la revendication 1, dans lequel ledit matériau ayant un coefficient de frottement dynamique avec de l'acier ou du fer aciculaire d'environ 0,15 comprend de la fonte.

3. Socle (24) selon la revendication 1 ou 2, comprenant un élément d'appui (60) situé entre ledit premier élément de frottement (40) et ladite première face (32) de ladite première mâchoire de socle (26).

4. Socle (24) selon la revendication 3, dans lequel ledit élément d'appui (60) comprend une plaque de polytétrafluoroéthylène.

5. Socle (24) selon l'une quelconque des revendications précédentes, dans lequel le premier élément d'usure (40) est fixé à ladite première face (32) de ladite première mâchoire de socle (26), la surface de frottement avant (52) dudit premier élément d'usure (40) étant adapté pour venir en prise avec ladite première cale de frottement (39), et dans lequel le second élément de frottement (40) est fixé à ladite seconde face (34) de ladite seconde mâchoire de socle (28), la surface de frottement avant (52) du second élément d'usure (40) étant adaptée pour venir en prise avec la seconde cale de frottement (39).

6. Socle (24) selon l'une quelconque des revendications précédentes, dans lequel la première (32) et la seconde (34) faces intérieures sont des faces inclinées.

7. Ensemble de console (35) et de socle (24) destiné à un bogie pour un véhicule ferroviaire (20) adapté pour recevoir un palier (37) et un axe de roue (38), cet ensemble comprenant :

un socle (24) selon l'une quelconque des revendications 1 à 5, dans lequel la première (26) et la seconde (28) mâchoires de socle définissent une cavité de socle (30) ;

une console (35) adaptée pour être placée dans la cavité de socle (30), la console (35) étant adaptée pour être couplée au palier (37) et à l'axe de roue (38) ;

une première cale de frottement (39) poussée élastiquement pour venir en prise entre la première mâchoire de socle (26) et la semelle (35) ; et

une seconde cale de frottement (39) poussée élastiquement pour venir en prise entre la seconde mâchoire de socle (28) et la console (35).

Drawing