SIDEFRAME PEDESTAL

SOCLE DE CADRE LATERAL

English Abstract

Freight truck castings on freight trucks have an interface between the freight car truck sideframe and a bearing assembly or bearing adapter. The present invention includes a sideframe with a pedestal jaw, placing a bearing assembly inside the pedestal jaw, and forming a pedestal roof in the pedestal jaw in a shape to evenly distribute a load between the pedestal roof and the bearing assembly. The present invention also provides for reducing load concentration on an interface between a pedestal roof and an axle. The present invention provides a sideframe with two pedestal roofs disposed at opposite ends of the sideframe, an axle placed under the pedestal roof, and an angled interface. The angled interface is formed between the pedestal roof and bearing adapter to reduce load concentration.

French Abstract

Les pièces coulées de voitures de fret sont pourvues d'un point de contact entre le longeron de la voiture et un ensemble porteur ou un adaptateur de palier. La présente invention concerne un longeron muni d'une plaque de garde qui renferme un ensemble porteur et forme une voûte de plaque de garde, ce qui lui confère une forme qui répartit de manière égale la charge entre la voûte de la plaque de garde et l'ensemble porteur. La présente invention permet également de réduire la concentration du poids en un point donné sur un point de contact entre la voûte de plaque de garde et un essieu. La présente invention concerne également un longeron muni de deux voûtes de plaque de garde disposées de part et d'autre du longeron, un essieu installé sous la voûte de plaque de garde, et une pièce de contact en angle. La pièce de contact en angle est située entre la voûte de la plaque de garde et l'adaptateur de palier, dans le but de réduire la concentration de la charge en un point donné.

Claims

CLAIMS
What is claimed is:

1. A method of compensating for the deflection in an axle in a freight car
truck comprising
the steps of:
providing a sideframe with a pedestal roof having a downwardly facing surface;
placing a bearing assembly having an upwardly facing surface under the
pedestal roof;
and
forming the downwardly facing surface of the pedestal roof in a shape to which
registers with the
upwardly facing surface when said axle is in a deflected configuration to
equally distribute load
axially across the bearing assembly.

2. The method of claim 1 further comprising the step of placing the bearing
assembly in a bearing adapter before placing the bearing assembly under the
pedestal roof.
3. The method of claim 1 wherein the shape in the pedestal roof is an angle to
conform to a bearing adapter, the bearing adapter in substantially even
contact with the
pedestal roof when the freight car truck is under load.

4. The method of claim 3 wherein the deflection has a deflection angle in the
range of 0 degrees to 5 degrees.

5. A method of reducing a load concentration on an interface between a
sideframe and an axle in a freight car truck comprising the steps of:
providing a sideframe with two pedestal roofs disposed at opposite ends of the
sideframe;
placing an axle inside the pedestal roof;
providing a bearing assembly and bearing adapter connected to an end of the
axle, forming an angled interface between the pedestal roof and the bearing
adapter,
wherein the bearing adapter contacts the pedestal roof and transfers a freight
car

7


load substantially evenly to the bearing assembly.

6. The method of claim 5 wherein the bearing adapter is shaped at an acute
angle to the pedestal roof.

7. The method of claim 6 wherein the angle of the bearing adapter to the
pedestal roof is between 0 and 5 degrees.

8. The method of claim 6 wherein the bearing adapter contacts the pedestal
roof substantially evenly and transfers the freight car load substantially
evenly
from the pedestal roof to the bearing assembly.

9. A freight car truck comprising:
a sideframe with a pedestal jaw;
a bearing assembly within the pedestal jaw;
a pedestal roof formed in the pedestal jaw with an angled shape to
substantially evenly distribute a freight car load between the pedestal roof
and the bearing
assembly.

10. The freight car truck of claim 9 wherein the bearing assembly has a
bearing adapter, the bearing adapter contacting the pedestal roof.

11. The freight car truck of claim 9 wherein the shape is an acute angle with
an edge to conform to an outside edge of the bearing adapter under a no load
condition.
12. The freight car truck of claim 9 wherein the shape is an axial angle in
the range of 0 to 5 degrees.

13. The freight car truck of claim 9 wherein the deflection is an angled arc
with a center of the arc being parallel to the sideframe.

8


14. The freight car truck of claim 10 wherein the angled shape in the pedestal

roof is in substantially even contact with the bearing adapter when the
freight car is
under load.

15. A freight car truck comprising:
a sideframe with two pedestal roofs disposed at opposite ends of the
sideframe;
an axle placed under the pedestal roof; and
a bearing assembly and bearing adapter connected to an end of the axle forming

an angled interface between the pedestal roof and the bearing assembly and
transfers
a freight car load substantially evenly to the bearing assembly.

16. The freight car truck of claim 15 wherein the bearing adapter is shaped at

an acute angle to the pedestal roof.

17. The freight car truck of claim 16 wherein the angle of the bearing adapter

to the pedestal roof is between 0 and 5 degrees.

18. The freight car truck of claim 15 wherein the bearing adapter contacts the

pedestal roof substantially evenly and transforms the freight car load
substantially evenly
from the pedestal roof to the bearing assembly.

19. The device of claim 15 wherein the angled interface is an arc with a
center of the arc being parallel to a sideframe.

9

Description

CA 02574323 2007-01-18

SIDEFRAME PEDESTAL
BACKGROUND OF INVENTION

10011 The present invention relates to railway freight car trucks and, more
particularly, to
a freight car truck sideframe and the interface between the freight car truck
sideframe and a
bearing assembly.

[002] Freight car truck sideframes are known that have a sideframe pedestal
design which
is flat and in a horizontal plane or having 15 inches of maximum radius along
the longitudinal
edges starting a specified distance from the center line. The 15 inches of
maximum radius option
is shown in Association of American Railroads (AAR) standard S-325-94,
"Limiting Dimensions
for AAR Alternate Standard Pedestal Type Sideframes."

[003] The flat horizontal roof of such known designs do not compensate for a
deflection
of the bolster and axle that occurs under loaded car conditions. With
increasing axle loads
commonly used in service, this deflection has increased. The combination of
increased axle load
and increased deflection has caused additional load to be concentrated on the
bearing assembly,

for example the inner race of the roller bearing elements that is part of the
bearing assembly,
located at the end of the axle. One example of a bearing assembly is a roller
bearing and the load
would concentrate on the inner race of the roller bearing elements. This
increased load
concentration reduces the life of the bearing assembly. Another embodiment of
the present
invention has a bearing assembly including a bearing adapter.

[004] One embodiment of the present invention provides an angled non
horizontal
surface in a sideframe pedestal roof. The angle in one embodiment of the
present invention is
about the longitudinal axis of the sideframe. The angle is specifically
selected to compensate for
- 1-


CA 02574323 2007-01-18

the deflection in the bolster and axle structure when a car is loaded and
disperses the load about a
length on the bearing assembly to reduce the load concentration on the bearing
assembly.

25 [005] Another embodiment of the present invention provides an angled non
horizontal
surface in a bearing adapter. The angle in the bearing adapter is about the
longitudinal axis of
the sideframe pedestal roof. The angle is specifically selected to compensate
for the deflection in
the bolster and axle structure when a car is loaded and disperses the load
about a length on the
bearing assembly to reduce the load concentration on the bearing assembly.

30 SUMMARY OF THE INVENTION

[006] It is an object of the present invention to provide a method of
compensating for the
deflection in a bolster in a freight car truck under load.

[007] It is another object of the present invention to provide a method of
evenly
distributing a load concentration on an interface between a sideframe pedestal
and an axle.

35 [008] It is another object of the present invention to provide a device for
compensating
for the deflection in an axle in a freight car truck under load.

BRIEF DESCRIPTION OF DRAWINGS

[009] FIG. 1 is a perspective view of a railway truck showing a sideframe
pedestal
according to one embodiment of the present invention;

40 [0010] FIG. 2 is a side cross sectional detailed view of a bearing
assembly, axle and
sideframe in an unloaded condition, according to an embodiment of the present
invention;

[0011] FIG. 3 is a side cross sectional view of a prior art bearing assembly,
axle and
sideframe in an unloaded condition;

~2-


CA 02574323 2007-01-18

[0012] FIG. 4 is a side cross sectional view of a prior art bearing assembly,
wheel set and
45 sideframe in a loaded condition;

[0013] FIG. 5 is a side cross sectional view of a bearing assembly, axle and
sideframe in
an unloaded condition, according to an embodiment of the present invention;

[0014) FIG. 6 is a side cross sectional view of a bearing assembly, axle and
sideframe in
a loaded condition, according to an embodiment of the present invention;

50 [0015] FIG. 7 is a side cross sectional view of a bearing assembly, axle,
and sideframe in
an unloaded condition, according to a second embodiment of the present
invention;

[0016] FIG. 8 is a side cross sectional view of a bearing assembly, axle and
sideframe in
a loaded condition, according to a second embodiment of the present invention.

DETAILED DESCRIPTION

55 [0017] Referring now to FIG. I of the drawings, a railway vehicle truck 10
is shown
having a sideframe pedestal 11. Railway truck 10 has a first sideframe 12 and
a second identical
sideframe 12 laterally spaced and disposed in a generally parallel
relationship to truck
longitudinal axis L. Each sideframe 12 has an inboard face 13 and an outboard
face 14.
Sideframes 12 are mounted in pairs on a pair of spaced wheelsets 4. One
wheelset 4 includes an

60 axle 16, mounted wheels 18 and bearing assemblies 25. An axle 16 has a
first axle end 15 and a
second axle end 17. Bearing assemblies 25 are mounted at the first axle end 15
and second axle
end 17.

[0018] Each sideframe 12 has a pedestal jaw 50 at each end and a bolster
opening 23 at
the sideframe midsection. A bolster 20 extends between each of the sideframe
bolster openings
- 3 ..,


CA 02574323 2009-06-10

70 23 and is supported by springs 22. Bolster 20 may be connected to a railcar
underside at a
centrally-located center plate 2 1.

[0019] Referring to FIG. 2, according to one embodiment of the present
invention, bearing
assembly 125 is held on axle end 117 by backing ring 125A and by axle end cap
125B. Bearing
assembly 125 has a roller type bearing 125c with outer race 126 and inner race
124. The 70 inner

75 race 124 is pressed onto axle end 117 and rotates with the axle end 117.
Bearing adapter 170
contacts outer race 126. Pedestal roof 111 contacts bearing adapter 170, in
some applications
there may not be a bearing adapter 170 and the pedestal roof may be in direct
contact with the
outer race 126.

[0020] Referring to Fig. 3 and 4, a prior art design is shown. In Fig. 3, is
pedestal jaw 50, 75
80 bearing assembly 25 bearing adapter 70, and pedestal roof 11 are shown
under a no load
condition. Pedestal roof 11 is generally horizontal, and under the no load
condition the load is
evenly distributed. It should be noted that loading in bearing assembly 25 in
an unloaded
condition is quite insignificant, with only the weight of the unloaded freight
car, typically from
40,000 to 60,000 pounds, distributed over four locations on two freight car
trucks. Under load,

85 80 200,000 to 250,000 additional pounds of loading is added, one half to
each truck. As shown in
Fig. 4, pedestal jaw 150, bearing assembly 25, bearing adapter 70, and
pedestal roof 11 are
shown under load. A deflection angle a of from 0-5 degrees is produced from
the loaded
condition, with the load concentrated the inner portion of bearing outer race
26 causing
unnecessary stress on bearing assembly 25. 85

90 100211 Referring to FIG. 5, according to one embodiment of the present
invention, pedestal roof
111, bearing assembly 125, and adapter 170, are shown with axle 117 and wheels
118 and
sideframe 112 and bolster 20 under no load. Pedestal roof 111 has a deflection

4


CA 02574323 2009-06-10

compensator angle b cut into pedestal roof 111. The deflection compensator
angle b of from 0 to
degrees, is shaped to evenly distribute the load over a bearing adapter 170,
bearing assembly
95 90 125, under loaded conditions.

[0022] Under the unloaded condition of Figure 5, the load from an empty
freight car is
concentrated at the outer portions of bearing adapter 170 and outer bearing
race 126. However,
as explained above, the bearing loading under such an unloaded condition is
quite insignificant.
Axle 117 is, for all purposes, straight. 95

100 [0023] Referring now to Fig. 6, according to the embodiment of Fig. 5 of
the present invention,
pedestal jaw 150, bearing assembly 125 and adapter 170 are shown under a
loaded condition.
Axle 117 is bowed due to the loading received at the ends through bearings
125, bearing adapter
170 and sideframes 112. Bolster 20 is also bowed, resulting in an outward
rotation of side frame
112. However, as pedestal roof 111 has a deflection compensator angle b 100
cut into pedestal

105 roof 111, the load is evenly distributed from pedestal roof 111 to bearing
adapter 170 to bearing
assembly 125.

[0024] Referring to Fig. 7, another embodiment of the present invention is
shown. Pedestal jaw
250, bearing assembly 225, and bearing adapter 270 are shown, along with
sideframe 212, axle 2
17 and wheels 218. Bearing adapter 270 has a deflection 105 compensator angle
c cut into it. The

110 deflection compensator angle is between 0 and 5 degrees. Such angle is
shaped to evenly
distribute load over bearing adapter 270, and bearing assembly 225 under
loaded conditions.
[0025]Under the unloaded conditions of Fig. 7, the load from an empty freight
car is
concentrated at the outer portion of bearing adapter 270 and thusly outer
bearing race 226.

5


CA 02574323 2009-06-10

However, as explained above, the bearing loading under such an unloaded
condition is quite
115 insignificant. Axle 117 is for all purposes, straight.

[0026] Referring now to Fig. 8, the embodiment of Fig. 7 is shown under a
loaded condition.
Pedestal jaw 250, bearing assembly 225 and adapter 270 are present. Axle 217
is bowed due to
the loading received at its ends through bearings 225, bearing adapter 270,
and 115 sideframe 12.
Side frame 220 is also rotated outward due to bowing of bolster 20 under load.
However, as

120 bearing adapter 270 has a deflector compensator angle c cut into it,
pedestal roof 211 has its load
evenly distributed from pedestal roof 211, through bearing adapter 270 to
bearing assembly 225.
HAMLA W\ 237206\1

6

Representative Drawing