Railcar truck bearing adapter construction

A railcar truck, bearing-adapter assembly for an axle end has vertically extending arms to securely capture and maintain a roller bearing and axle end assembly at about an as-assembled reference position within the adapter assembly and sideframe pedestal jaw, where the as-assembled reference position has the railcar truck side frames about parallel and the axles about normal to the side frames, and which adapter assemblies in the opposed sideframe pedestal jaw are secured within a cross-passage at the ends of the truck side frames to capture and retain the axle ends in opposing side-frame pedestal jaws at about the reference as-assembled position to inhibit both horizontal and vertical axle displacement truck and thus minimize railcar truck warping.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a bearing adapter assembly for a railcar 
truck. A railcar truck typically has a pair of parallel sideframes 
transversely coupled by a bolster at about the sideframe longitudinal 
midpoints. A pair of axles, which are generally parallel to the bolster 
and each other, join the respective forward and rearward opposed ends of 
the sideframes. The sideframe longitudinal axes are likewise approximately 
parallel and define a generally horizontal plane at a reference or 
as-assembled condition of the truck. The axles usually include journal 
bearings and bearing adapters on the axle ends, which adapters are nested 
and secured in the pedestal jaws at the sideframe ends. 
Within this truck environment, the present invention more particularly 
provides tightly secured bearing adapters to firmly hold the axle bearing 
in position at each pedestal jaw to avoid displacement relative to the 
longitudinal direction of the sideframe, which displacement or variation 
can result in truck "warping". Past research has illustrated railcar truck 
warping induces truck hunting during railcar travel, which truck warping 
causes undue wear on rails and wheels, as well as increasing fuel usage. 
In extreme cases, warping or high-speed hunting may potentially be an 
unsafe operational condition leading to railcar derailment. Truck warping 
also has a detrimental effect on truck steering or ability of the railcar 
to negotiate a curve. 
2. Description of the Prior Art 
In a three-piece railcar truck assembly, the sideframes and bolster are 
generally aligned and square. That is, the side frames are parallel to 
each other but normal to the axles and bolster of the assembly, and, the 
axles and bolster are approximately parallel to each other. At certain 
railcar speeds, the truck may become dynamically unstable, which may 
loosely be defined as truck hunting. In "Car and Locomotive Cyclopedia" 
(1974), truck hunting is defined as "an instability at high speed of a 
wheel set (truck), causing it to weave down the track, usually with the 
(wheel) flanges striking the rail." As a consequence, review and analysis 
of truck hunting has been the subject of many past and ongoing research 
efforts within the rail industry by truck suppliers, car builders and 
railroad lines, as this is an undesirable condition for economic, 
operational and safety considerations. These past research efforts have 
noted a significant relationship between truck warping and resultant truck 
hunting. Some of these research efforts and past conclusions are discussed 
in the ASME paper, "Truck Hunting in the Three-Piece Freight Car Truck" by 
V. T. Hawthorne, which paper included historical reference to earlier 
research in this field. One of these earlier researchers noted ". . . that 
in the empty car the higher column force of the constant column damping 
provides a greater warp stiffness and, consequently, yields a higher 
critical (truck) hunting speed." The project for this cited ASME paper was 
designed to measure the following parameters: warp stiffness; lateral 
damping force; and, lateral spring rate. 
In the above-noted Hawthorne project, the warp stiffness results duplicated 
earlier test results, which confirmed the appreciable decrease in warp 
stiffness as the warp angle increased to 1.degree.(60 minutes) of angular 
displacement. Further, earlier warp stiffness data showed that a 
displacement of 1.degree. in the warp angle represented the maximum warp 
travel of a relatively new truck during truck hunting. Therefore, at warp 
angles prevalent in truck hunting, the warp stiffness fell considerably 
below the values necessary to raise the critical speed of hunting above 
the normal operating range of the freight railcar. 
An application of the test results illustrated a new railcar truck running 
at a speed above 60 miles per hour with track inputs causing warp angles 
less than 0.3.degree. would not be expected to hunt. However, if the warp 
angle suddenly increased to 1.0.degree. due to a track irregularity, it is 
expected that the critical truck hunting speed of the railcar would drop 
to about 52 miles per hour and intermittent truck hunting would occur. 
A three-piece railcar truck generally allows a considerable amount of 
relative movement between the wheel-axle assembly and the supporting side 
frame at the side-frame pedestal jaw. This movement may be due to the form 
of the connection between the journal end of the wheel and axle, as well 
as to machining or assembly tolerances permitted in the various 
components, such as manufacturing dimensional tolerances for the 
side-frame pedestal jaw, bearing adapter, and the axle. U.S. Pat. No. 
3,211,112 to Baker discloses an assembly to damp the relative lateral 
movement between the wheel and axle assembly, and the associated side 
frame. More specifically, a resilient means or member is provided between 
the top of the journal end of the wheel and axle assembly, and the 
associated side frame member to produce varying frictional forces for 
damping the relative movement between the assembly and the side frame. The 
Baker-'112 patent recognized the undesirability of transmitting track 
perturbations through the axle, sideframes and bolsters, but inhibition of 
this force transmission was to be accomplished by damping the disturbances 
caused by lateral axle movements, not by suppressing their initiation. 
In U.S. Pat. No. 3,274,955 to Thomas and also in U.S. Pat. No. 3,276,395 to 
Heintzel, a roller bearing adapter is illustrated with an elastomer on the 
upper part of the cap plate, which adapter is positioned in the side frame 
pedestal jaw with the elastomer between the pedestal jaw roof and the 
adapter for relieving exposure to high stresses. A similar concept is 
shown in U.S. Pat. No. 3,381,629 to Jones, which provided an elastomeric 
material between each bearing assembly and the pedestal roof to 
accommodate axial movements of the bearing assemblies of each axle and to 
alleviate lateral impact to the side frame. 
Other assemblies and concepts have been utilized for maintaining a truck in 
a square or parallel relationship. In U.S. Pat. No. 4,103,623 to Radwill, 
friction shoes are provided to frictionally engage both the side frame 
column and bolster. This friction shoe arrangement is intended to increase 
the restraining moment, which is expected to result in an increased truck 
hunting speed. The friction shoes had contact surfaces with appropriate 
manufacturing tolerances to control initial contact areas for developing a 
maximum restraining moment. 
U.S. Pat. No. 4,192,240 to Korpics provided a wear liner on the roof of a 
sideframe pedestal jaw. The disclosure recognized the detrimental effects 
of having a loose wear liner in the pedestal jaw. Wear liners are provided 
against the roof of the pedestal jaw to reduce wear in the roof caused by 
oscillating motions of the side frame relative to the wheel-axle assembly 
and the bearing. The disclosed wear liner included upwardly projecting 
tabs to grip the roof and sideframe to inhibit longitudinal movement of 
the wear liner, and downwardly projecting legs to cooperate with 
pedestal-jaw stop lugs to inhibit lateral movement of the wear liner 
relative to the roof. The stop lugs of the pedestal jaw are positioned on 
opposite sides of the depending legs of the jaw, which lugs are engageable 
with the downwardly depending wear liner legs. 
U.S. Pat. No. 3,621,792 to Lich provides a pedestal jaw opening with 
outwardly sloped sidewalls and a bearing adapter with sloped sidewalls 
positioned in the jaw opening. An elastomeric component is positioned 
between the adapter and both of the pedestal sidewall and roof, which 
elastomer provides resistance in compression and yieldability in shear, as 
well as sufficient softness for cushioning. By positioning the elastomeric 
pad between all the interfaces of the adapter and the pedestal jaw, 
metal-to-metal contact is prevented along with wear and transmission of 
noise and vibration from the track to the truck framing. Similarly in U.S. 
Pat. Nos. 3,699,897 and 4,416,203 to Sherrick, a resilient pad is provided 
between the bearing adapter and the side frame. 
U.S. Pat. No. 4,072,112 to Wiebe has an elastomeric positioning means 
placed intermediate the bearing carrier and one of the pedestal jaws to 
bias the bearing carrier into direct communication or engagement with the 
opposite pedestal jaw, which limits relative angular movement and linear 
displacement of the wheel set to the side frame. 
U.S. Pat. Nos. 4,108,080 and 4,030,424 to Garner et al. teach a rigid 
H-frame truck assembly having resilient journal pads in the pedestal jaws. 
The truck provided by these developments demonstrated improved riding 
characteristics. Similarly U.S. Pat. Nos. 4,082,043 and 4,103,624 to 
Hammonds et al. disclosed an integral H-frame truck with resilient 
elements in the journal bearings. 
In U.S. Pat. No. 4,242,966 to Holt et al., a railcar truck has a transom 
with a pair of tubes rigidly connected between the longitudinally 
extending side frames. The transom allows vertical movement of the side 
frames but resists longitudinal displacement of the side frames with 
respect to each other. 
A suspension arrangement with at least two annular elastomeric shock 
absorbers having an optimum adjustability in the longitudinal and 
transverse directions of the vehicle is provided in U.S. Pat. No. 
4,841,875 to Corsten et al. 
Alternative means for the insertion and securing of a wear liner against a 
pedestal jaw roof are taught in U.S. Pat. Nos. 4,034,681 and 4,078,501 to 
Neumann et al. and 4,192,240 to Korpics, which patents have a common 
assignee. These disclosed apparatus were to provide improved means for 
securing a wear liner in the jaw to minimize its movement and to improve 
the assembly means. The wear liners are provided with downwardly depending 
legs and stop lugs positioned to inhibit movement of the wear liner, such 
as in the lateral direction relative to the roof. 
U.S. Pat. No. 4,428,303 to Tack illustrates a clip-on pedestal wear plate 
especially adapted for worn pedestal surfaces. A pair of wear plates, or a 
single member with a central portion of the plate removed, may be used in 
the disclosed structure. 
All of the above-noted apparatus disclose a journal bearing assembly or an 
assembly for a rail truck axle end, which assembly is operable in the 
pedestal jaw. The disclosures recognized the desirability of keeping the 
truck side frames aligned with each other to avoid truck hunting. The 
several disclosures provided a plurality of alternative resilient means or 
structures in the pedestal jaw and around the axle journal bearings, but 
none of the cited structures addressed the problem of maintaining the 
bearing adapter, and consequently the axle and side frames, in their 
aligned positions. Several of the above-noted references specifically 
utilized elastomeric or resilient components in the pedestal jaw or in 
association with the journal bearing to accommodate the disturbances and 
flexing motions experienced by the axles and side frames. 
More specifically, it is necessary to provide a bearing and bearing adapter 
assembly with a moment arm sufficient to resist the torque from the wheels 
and axles. This torque acts to induce yawing or rotation of the axle 
inside the side frame pedestal jaw in a horizontal plane, which plane 
includes the longitudinal axis of the axle. The underlying operational 
objective of any axle retaining apparatus is to provide an assembly to 
maintain the axle or axle end in its prescribed relationship to the side 
frame, which relative position is usually normal to the side frame. The 
amount of axle rotation considered detrimental to the operation of the 
railcar truck has been noted as less than one degree (1.degree.) of 
angular displacement from its reference or as-assembled position. To 
assist in the assembly of the axle end and bearing, which act as a unit, 
and to stably retain the unit in the pedestal jaw at its as-assembled 
position, it is necessary to inhibit horizontal motion of this axle 
end-bearing assembly in the pedestal jaw along the sideframe longitudinal 
axis. The bearing adapter and pedestal jaw arrangement should maintain the 
adapter in its reference position while avoiding yawing of the axle and 
bearing in the pedestal jaw. 
SUMMARY OF THE INVENTION 
Each side frame for a railcar truck usually has a pedestal at both of its 
longitudinal ends with openings or pedestal jaws at each end to receive 
the journal bearing ends of the axle shafts. The railcar longitudinal axis 
extends between the opposite ends of the railcar and, the sideframe and 
truck longitudinal axes are generally parallel to this railcar axis. These 
journal or wheel bearings are mounted on each axle end and generally 
secured in bearing adapters in the pedestal jaws. A railcar truck assembly 
usually has two axles, which extend between a pair of side frames, and are 
intended to remain aligned and parallel during railcar travel. The 
above-noted bearing adapters are generally secured in the pedestal jaw by 
various means, such as interlocking adapter and jaw surfaces. Wear plates 
are frequently positioned between the adapter and the pedestal jaw roof to 
minimize wear from the repeated flexing of the adapter in the pedestal jaw 
during railcar travel. 
The present invention provides a bearing adapter in the pedestal jaw, which 
adapter has vertically extending sides and generally contacts the axle 
journal bearing, or its bearing race, tangentially at its horizontal 
diameter. Contact and retention of the journal bearing at its horizontal 
diameter by the vertically extended bearing adapter legs provides the 
following: a more secure grasp of the journal bearing by the adapter; a 
more secure nesting of the adapter in the pedestal jaw; and, a greater 
resistance to twisting of the adapter, and thus the axle, in the pedestal 
jaw. These improvements reduce warping and truck hunting, as well as 
reducing potential wear at the adapter to bearing interface. 
It is recognized that truck hunting is not eliminated per se, but 
reductions are expected in the railcar truck angling. The amount of 
distortion of the truck geometry from its reference, as-assembled 
alignment and position, that is distortion where the axles are no longer 
perpendicular to the axes of the sideframes, is expected to decrease from 
the present distortion experienced by railcar trucks. Further, the railcar 
critical speed, that is the speed where truck hunting becomes a negative 
operating factor, may be expected to increase beyond the normal operating 
speed of the railcar. In addition, alternative embodiments provide means 
for avoiding axle and bearing movement transverse to the sideframe 
longitudinal axis, which thereby avoids metal-to-metal wear. 
BRIEF DESCRIPTION OF THE DRAWINGS

DETAILED DESCRIPTION OF THE INVENTION 
In FIGS. 13 and 14, railcar truck or truck assembly 10 is illustrated with 
first side frame 12 and second side frame 14, which side frames 12 and 14 
are in a generally parallel relationship to truck longitudinal axis 16. A 
freight railcar (not shown) is usually provided with a railcar truck 10 at 
both ends of the railcar. First side frame 12 and second side frame 14 
with respective longitudinal axes 13 and 15 are connected by bolster 18 at 
about their respective midpoints 20 and 22. Bolster 18 with longitudinal 
axis 19 is generally parallel to first axle 28 and second axle 30. Each of 
first and second axles 28, 30 have a first end 34, a second end 36 and a 
longitudinal axis 37, as noted in FIG. 12. Further, bolster 18 is 
generally transverse to first and second side frames 12, 14, and truck 
longitudinal axis 16. Each of first and second side frames 12, 14 has a 
first pedestal jaw 24 and a second pedestal jaw 26 at their respective 
longitudinal first and second side frame ends 23, 25. The respective side 
frame first and second pedestal jaws 24, 26 of parallel first and second 
side frames 12, 14 are generally aligned and have an axle end 34 or 36 of 
one of axles 28 and 30 nested therein. 
Wheels 32 are mounted at each axle end 34 and 36 of each axle 28 and 30 on 
inboard side 42 of each of side frames 12 and 14 in FIG. 13. As noted in 
an exploded view in FIG. 12, each wheel 32 is secured on its respective 
axle end 34, 36 by a journal bearing 38 and an end cap 40. 
FIG. 12 illustrates in an exploded view side frame 12 and axle 28 along 
with ancillary assembly components. More specifically in first bearing 
arrangement 45, journal or roller bearing 38 and conventional locked 
bearing adapter 44 are shown at second pedestal jaw 26 of side frame 12. 
Alternative bearing arrangement 46 at pedestal jaw 24 is noted with 
journal lubricating pad 48 and solid journal bearing 50, which bearing 
arrangement 46 is known in the art. Locked bearing adapter 44 has a 
centrally positioned notch 52 on both longitudinal sides for mating with 
lugs 54 in pedestal jaw opening 56, which coupling of notch 52 and lug 54 
secures adapter 44 in opening 56. A plan view of this lug 54 and notch 52 
configuration is noted in FIG. 15. 
After assembly of truck 10, journal bearing 38 on axle end 34 is nestable 
against arcuate under surface 58 of bearing adapter 44. Journal bearing 38 
includes an outer bearing race or cup 168 (cf. FIG. 4A) to secure the 
individual bearings within the bearing assembly, and reference to journal 
bearing 38 is to the bearing assembly. Bearing adapter 47 or 44 and 
bearing 38 in FIGS. 2 and 12, respectively, are illustrative of an extant 
bearing structure. In FIG. 2, the downwardly extending side arms 62 and 64 
of adapter 47 only capture a portion of the circumferential surface of 
journal bearing 38. In the configuration of bearing 38 and adapter 47 of 
FIG. 2, movement of truck 10 along railtracks causes perturbations in 
truck 10 initially producing vertical displacement of adapter 47 relative 
to journal 38, which allows longitudinal deflections of axles 28 and 30 
along side frame axes 13 or 15. These perturbations and deflections can 
produce resultant displacement of adapter 47, as noted by vector arrow 66 
in FIG. 2, which vector has a vertical displacement component `x` and a 
longitudinal displacement component `y`. As noted above, the resultant 
displacement of axles 28 and 30, and adapters 47 or 44 is related to the 
truck hunting and warping phenomena. 
Although each of side frames 12 and 14 have a first pedestal jaw 24 and a 
second pedestal jaw 26, only one of pedestal jaws 24, 26 and the 
associated wheel bearing 38 and bearing adapters 44 or 47 will be 
described. It will be understood that the description of the wheel bearing 
and bearing adapter at one pedestal end is applicable to each pedestal jaw 
in a truck assembly 10. 
FIG. 1 is a conceptual illustration of a bearing adapter or weight-bearing 
apparatus 47 to be nested in a pedestal jaw 26 for securing journal 
bearing 38 and its mated axle end 34 or 36. Bearing adapter 47 has a first 
vertically downward extending arm 70 and a second vertically downward 
extending arm 72, which arms 70 and 72 cooperate with arcuate under 
surface 58 to provide a u-shaped slot 74 for journal bearing 38. Slot 74 
is preferably sized to securely mate with bearing 38. Inner walls 76 and 
78 of slot arms 70 and 72, respectively, are tangential to bearing outer 
surface 80 at opposite outer points 82 and 84 of bearing horizontal 
diameter 86. Arms 70 and 72 extend vertically downward beyond tangential 
contact with outer points 82 and 84 to securely capture bearing 38 within 
adapter 47. In this illustration, bearing adapter 47 functions as the 
locking plate, the adapter and the load bearing apparatus. Thus, adapter 
47 captures and secures bearing 38 and axle 28 to securely maintain them 
in pedestal jaw 24 or 26. In this configuration, adapter inner walls 76, 
78 will maintain contact with bearing surface 80 at diameter 86 during 
vertical movement of adapter arms 70 and 72, and thus adapter 47 continues 
to inhibit longitudinal displacement component "y" noted in FIG. 2, which 
movement would be parallel to sideframe 12 or 14. 
Utilization of locking plate 88 with bearing or bearing assembly 38 and 
adapter 44 is shown in FIGS. 4, 4A, 5, 5A, 7, 7A, 7B, 7C and 7D. The 
several figures illustrate alternative embodiments or structures, and 
FIGS. 7C and 7D depict the relationship between these embodiments. In the 
embodiment of FIGS. 4 and 7A, which FIG. 7A is an end view of pedestal jaw 
26 and axle 28, locking plate 88 is noted in dashed outline. In the 
embodiment of FIGS. 7, 7A and 7B, locking plate edge 90 is in proximity to 
bearing outer surface 80 at diametral contact points 82 and 84, which are 
about the outer points of a horizontal diameter 86 of the bearing end 
face. Bearing adapter 44 in FIGS. 7, 7A and 7B broadly has a similar 
structure to adapter 44 of FIG. 12, which adapter arrangement includes 
notch 52 and lugs 54 in opening 56. 
Locking plate 88 on outboard sideframe surface 43 in FIG. 7A has first 
sidearm 150 and second sidearm 152 with arcuate locking plate edge 90 
joining sidearms 150, 152, which sidearms 150, 152 provide the side 
support for bearing assembly 38 at outer horizontal diameter points 82 and 
84. In this embodiment, arcuate edge 90 is in contact with outer surface 
80 of bearing 38 and shares the load or force bearing function with 
bearing adapter 44. Wear plate or auxiliary component 91 is illustrated as 
an independent component, but it may also be incorporated with adapter 44 
and locking plates 88 and 89 in a single cast or machined part. Locking 
plate 89 is similar to locking plate 88 but mounted on inboard surface 42, 
and it may be altered to conform to the available structure and contour of 
the sideframe. In FIG. 7, locking plate 88 includes an arcuate cutout 
providing a separation distance `z` between the bearing outer surface 80 
at the upper portion of bearing assembly 38 and the arcuate locking plate 
edge 90 at its vertical upper edge. As in FIG. 7A, locking-plate side arms 
150 and 152 maintain tangential contact with bearing outer surface 80 at 
horizontal diameter endpoints 82 and 84, however, relief section or 
separation distance `z` provides adequate displacement for side frame 12 
to rock or tilt about side frame longitudinal axis 13 or 15, that is a 
rotational movement between side frame, outboard wall surface 43 and 
inboard wall surface 42. Allowance for the side frame rocking motion 
avoids any potential binding between edge 90 of locking plates 88 or 89, 
which is noted on inner surface 42 of FIG. 4A, and bearing outer surface 
80 as rail truck 10 traverses rail tracks. In this embodiment, relief 
section `z` avoids vertical loading of locking plates 88 or 89 and all 
vertical loads or forces are borne by adapter 44. 
An alternative embodiment is shown in an elevational view in FIGS. 7B and 8 
with a locked bearing adapter alternate structure 49, which may also 
generally be compared to adapter 44 of FIG. 12. The wear plate or 
auxiliary component is incorporated with adapter 44 and locking plates 88 
and 89 in a single cast or machined part. In FIG. 7B, adapter 49 includes 
outboard locking plate 88 and inboard locking plate 89 as a one-piece 
integrated component. Adapter 49 has downwardly extending arms cooperating 
to define notches 52 (cf., FIGS. 12 and 15) for mating with lugs 54 in 
opening 56, which arms are similar to arms 60, 62 and 64 noted in FIG. 12, 
as well as the fourth and similar arm 63 not visible in FIG. 12. However, 
the structure of adapter 49 includes inner walls 76, 78 of respective 
downwardly extending arms 70 and 72 tangentially contacting outer bearing 
surface 80 at horizontal bearing diameter 86. The upper portion of adapter 
44 or adapter structure 49 is firmly positioned and maintained against 
pedestal opening roof 98. Locking plate 100 in FIG. 8, which is similar to 
locking plate 88 and is separately designated to distinguish its 
structure, is integral with adapter 49 and secured to pedestal jaw 26 by 
means known in the art. A second locking plate, similar to locking plate 
89 above in FIG. 4A, is positioned inboard of side frame 12. 
In the embodiment of FIGS. 4 and 7A, mated adapter 47 and bearing 38 are 
secured in pedestal jaw 26 by locking plate 88, which can also be 
considered to illustrate the concept of carrying the vertical load by 
locking plate 88 without an auxiliary adapter 44. Plate 88 is secured to 
side frame 12 at pedestal jaw end 26 by means known in the art such as 
welding, brazing, rivets or bolts. 
The exemplary structure of FIGS. 4 and 7A is shown in cross-sectional 
detail in FIG. 4A with inboard locking plate 89 secured to inboard surface 
42 and outboard locking plate 88 secured to outboard surface 43 of side 
frame 12 or 14. In this illustration, roller bearing assembly 38 has 
roller bearings 39 and bearing outer surface 80. Locking plates 88 and 89 
firmly secure bearing assembly 38 in pedestal jaw opening 56 between 
inboard locking plate 89 and outboard locking plate 88 and against 
pedestal jaw roof 98. 
Bearing assembly 38 of FIG. 4A includes inboard seal wear ring 160 and 
outboard seal wear ring 162; cone and roller assembly 164; cone spacer 
166; bearing cup 168; seal 170; end cap 172; locking plate 174; lubricant 
fitting 176; cap screw 178; vent fitting 180; and, backing ring 182. This 
structure is merely illustrative of a roller bearing journal assembly 38, 
but clearly demonstrates the multiplicity of elements associated with 
adapter 44 or 47 at pedestal jaws 24, 26. Further, alternate securing 
means for locking plates 88 and 89 include weldment 184 and screw 186, 
which screw 186 is matable into aperture 188 of side frame 12 through port 
189 of plate 89. 
In the embodiment illustrated in FIG. 5, locking plate inner edge 90 
extends over bearing 38 at outboard surface 43 to securely anchor bearing 
38. A second locking plate (not shown), which is similar to locking plate 
89 in FIG. 4A, may be secured to inner or inboard surface 42 of side frame 
12 to securely hold bearing 38 in opening 74. In an alternative embodiment 
shown in FIGS. 5, 5A and 6, locking plate 88 includes a flange 92 and 
shoulder 94 arrangement inboard of locking plate inner edge 90 to secure 
bearing 38 and axle 28 in pedestal jaw opening 74. In this embodiment, 
axle end 34 or 36 extends beyond bearing assembly 38 an incremental 
distance. Flange 92 overlaps the outer edge of bearing lip 95 and bearing 
38 at the intersecting edge between bearing outer face 96 and bearing 
outer circumferential surface 80 to securely maintain bearing 38 in 
pedestal jaw opening 74. 
In FIG. 7C, the embodiments of FIGS. 4, 7 and 7A are overlayed in a 
cross-sectional arrangement of a sideframe, axle and journal bearing, and 
provide an illustration of the general relationship between these several 
embodiments. In this illustration, locking plates 88, as shown in FIG. 4, 
are provided on both inboard surface 42 and outboard surface 43 of 
sideframe 12. Auxiliary bearing adapter 44 is interposed between outer 
surface 80 of journal bearing 38 and the outer surface of pedestal jaw 
roof 98. Locking plates 88 extend below axle center line or axis 37 on 
journal bearing 38. In the solid line configuration, locking plates 88 
would contact bearing outer surface 80 to provide at least a sharing of 
the load on bearing adapter 44. However, dashed lines 99, which are noted 
in FIG. 7, illustrate the arcuate relief section in locking plates 88 of 
such FIG. 7. In this embodiment of FIG. 7, all the load is borne by the 
bearing adapter 44. 
FIG. 7D shows the embodiment of FIG. 5 on the cross-sectional view of 
sideframe 12, axle 28 and journal bearing 38. Although this illustration 
could have been provided in conjunction with the embodiments of FIG. 7C, 
it is separately shown for clarity. In FIG. 7D, locking plates 88 include 
flange 92 with shoulder 94 and demonstrates bearing adapter 44 extending 
beyond inboard and outboard sideframe surfaces 42, 43 and nesting against 
locking plates 88 and particularly flanges 90. Inside locking plate 88 
could also incorporate flange 92 on such locking plate 88, which would 
further restrict horizontal motion between a side frame and axle. 
An alternative illustration of a bearing adapter structure utilizing 
extended arms for securely grasping and retaining bearing 38 is shown in 
FIG. 9. In this figure, pedestal jaw opening 56 includes downwardly 
vertical sidewalls 101 and 103 connected to roof 98 by sloping segments 
102 and 104, respectively. Bearing adapter 51 in this embodiment may be 
cast, formed or machined to provide tight conformation of its mating or 
contacting surfaces 106, 108, 110, 112 and 114 to vertical sidewall 101, 
sloping segment 102, roof 98, sloping segment 104 and vertical sidewall 
103, respectively. This tightly fitted arrangement provides intimate 
contact between bearing 38, adapter 51, pedestal jaw 26 and side frame 12, 
which fitted arrangement readily accommodates transfer of forces from the 
interaction of wheels 32 and the rail track. Bearing adapter 51 could also 
be retained in position by stops, keys or other means known in the art. 
In FIG. 10, one-piece locking bearing adapter 51 has spring pads 120 
mounted on sloped segments 102 and 104, which pads 120 are a material with 
a high spring rate, such as rubber or an elastomeric material. Pads 120 
extend into pedestal-jaw opening 56 to assure a tight fit between adapter 
51 and pedestal jaw 26. Adapter vertical extending arms 70 and 72 are 
noted as tangential to contact points 82 and 84 at horizontal axis 86. The 
elastomeric material, such as high molecular weight polyurethane, is 
either fully compressed at assembly to inhibit any unwanted deflection 
during operation, or it may be incompressible after assembly. 
In FIG. 11, one-piece bearing adapter 51 with extending arms 70 and 72 
includes threaded stud 122 normally extending upward from upper portion or 
contacting surface 110 into aperture 124 in roof 98, which aperture and 
roof have countersunk port 126 to receive nut 128 for mating with threaded 
stud 122. Therefore, bearing adapter 51 with vertical extending arms 70 
and 72 tangentially contacting bearing 38 at contact surfaces 82 and 84, 
respectively, is securely fastened to side frame 12 and is operable to 
rigidly secure bearing assembly 38 and axle 28 in pedestal jaw 26 to 
minimize railcar truck warping and hunting. 
FIG. 3 illustrates an alternative conceptual embodiment to the above-noted 
structures, which embodiment includes a low-friction lining 130 between 
journal bearing assembly 38 and any of bearing adapters 47 and 51. This 
figure is shown with the structural illustration of FIG. 1 for 
demonstrative purposes and not as a limitation. In this figure, adapter 47 
includes low-friction liner 130, which usually has a uniform thickness, 
interposed between journal bearing outer surface 80 and adapter walls 76, 
58 and 78. Therefore, tangent contact points 82, 84 at horizontal diameter 
86 appear at inner wall surface 132 of liner 130. Thus, liner 130 reduces 
wear from motion between bearing assembly 38 and adapter 47 or 51(cf., 
FIG. 11), which motion is perpendicular to the longitudinal axis 13 of 
side frame 12; allows and enhances the amount of bearing-to-adapter motion 
parallel to the bearing assembly centerline and perpendicular to side 
frame longitudinal axis 13 or 15; and, improves ease of assembly as the 
resilient surface will permit assembly of hardware mismatch from 
manufacturing tolerance buildup. However, as noted above, liner 130 must 
be fully compressed at assembly to insure a tight fit between adapter 47 
and bearing assembly 38. 
In operation, truck 10 is susceptible to perturbations and disturbances 
induced by the track structure, such as rail joints, crossovers and 
"frogs", as well as any random hazards, which perturbations can induce 
vertical, horizontal and lateral fluctuations and movements in axles 28 
and 30, bearing assemblies 38 or associated bearing adapters 44, 47, 49 or 
51, and cause parallelogramming in side frames 12 and 14. In FIG. 14, the 
potential relative horizontal angular displacement between sideframes 12 
and 14 at pedestal jaws 24 is noted by the exaggerated angle `w`. However, 
to reduce truck hunting, the angular displacement `w` must be less than 
1.degree., and preferably less than 0.1.degree.. 
The several embodiments of the invention taught and described above provide 
means for securely maintaining each bearing and axle end in their 
as-assembled reference position, which is generally normal to sideframes 
12 and 14. The several illustrated apparatus include means for providing 
the following: an integrated adapter; a locking plate or plates in 
cooperation with a bearing adapter; an adapter with a locking plate to 
share the vertical load; and, an adapter with a locking plate allowing the 
adapter to carry all of the vertical load. These vertical loads or forces 
are transmitted to the sideframe, axle and railcar from the wheels and 
axle, but the bearing adapter, such as adapters 44, 47 and 51, is firmly 
anchored in position within the pedestal jaw to inhibit movement of the 
axle and bearing, and consequently to inhibit truck hunting. 
The effects of the vertical loading from the railcar and the vertical or 
horizontal displacement of axle ends 34, 36 in pedestal jaws 24, 26 is to 
induce a torsional load in the pedestal jaw. The locking plate-bearing 
adapter assembly firmly secured in the pedestal jaws provides a resisting 
torque to the rotational moment, which moment is depicted in FIG. 15 at 
arrow 190. The resisting torque prevents yawing or horizontal rotation of 
the axle end, and consequently securely maintains the axle and sideframes 
in their relative as-assembled positions, inside the pedestal jaw opening, 
which is about 90.degree., or normal, to each other. The proscribed 
rotation of axle ends 34, 36 in a pedestal jaw is illustrated in FIG. 15 
by arrow 190. All of the above-noted several disturbances to the alignment 
of the various components at a static position can induce undesirable 
movement in the components relative to each other. 
As noted above, reduction in the movement of axles 28 and 30 longitudinally 
with respect to side frame axes 13 or 15, as well as reducing the 
rotational moment at the axle end, can aid in reducing the threshold speed 
for truck warping and hunting. The above-described locking plates 88 and 
89, and bearing adapters 44, 47 and 51 with extended arms 70 and 72 
capture journal bearing 38 against inner arcuate surface 58 at least 
circumferentially across horizontal diameter 86 of bearing 38. Further, 
utilization of locking plates 88, 89 with adapter 44, 47 or 51 provides 
similar means of retention of an axle and bearing in a pedestal jaw. This 
approximate semicircular capture of the generally cylindrical journal 
bearing assembly 38 allows bearing adapter 44, 47 or 51 to securely grasp 
and retain bearing assembly 38 and its associated axle 28 and 30 in 
pedestal jaw 24 or 26. Similar capture and retention of the bearing and 
axle ends in all of the pedestal jaws of the parallel sideframes generally 
secures the axles and sideframes in the as-assembled reference positions. 
Secure retention of journal bearing assembly 38, and axles 28 and 30 
minimizes longitudinal deflection of axles 28 and 30 to less than 
0.25.degree., that is relative movement of one axle end in a sideframe 
pedestal jaw with respect to the other axle end or sideframe, which has 
been found to significantly enhance the ability of the railcar truck to 
resist truck hunting. Secure retention of journal bearing 38 appears to 
increase the initiation speed for truck hunting beyond the normal 
operating speeds of most railcars. 
The present invention provides a bearing adapter assembly that may be 
conveniently nested in a pedestal jaw 26 of a railcar truck sideframe 12, 
14. However, it may also be secured to or cooperate with inner and outer 
surfaces 42 and 43 of sideframes 12 and 14 through a locking plate 88 or 
89 to secure the adapter against rotational motion in the pedestal jaw, 
which in turn dramatically inhibits rotation of the bearing and axle end 
of the railcar truck axle nested against the bearing adapter. Although the 
invention can provide securement of the adapter by extending the vertical 
arms of the pedestal jaw, the preferred embodiment provides securing the 
adapter by mechanically coupling the adapter to the sideframe sidewall or 
to the internal wall of the pedestal jaw opening. Anchoring the adapter in 
the pedestal jaw opening constrains the movement of the adapter and 
consequently reduces movement of the axle end and journal bearing secured 
therein. Further, securing the adapter and the locking plate to the 
pedestal jaw and the sideframe acts to maintain the reference position 
relationship between the adapter and sideframe sidewalls, that is 
generally normal. Maintenance of the physical relationship between the 
bearing assembly and the pedestal jaw acts to maintain the parallel 
relationship between the sideframes of a railcar truck and the generally 
normal relationship between the axles and the sideframes to thereby avoid 
truck hunting. 
As indicated above, the extending arms of the bearing adapter and locking 
plate assemblies 47 and 51 are noted as weight-bearing apparatus whether 
the assembly is a bearing adapter, a locking plate or the mated bearing 
adapter-locking plate. The components are operable as the noted assembly 
to receive the weight of the railcar and to retain the bearing in position 
in the pedestal jaw. 
While only particular embodiments of the invention have been described and 
claimed herein, it is apparent that various modifications and alterations 
of the invention may be made. It is the intention in the appended claims 
to cover all such modifications and alterations as may fall within the 
true spirit and scope of the invention.