Ex Parte Taillon

Board of Patent Appeals and Interferences

Jun 23, 2003

09772275 (B.P.A.I. Jun. 23, 2003)

1 Claim 1 was amended subsequent to the final rejection.
The opinion in support of the decision being entered today was not written
for publication and is not binding precedent of the Board.
Paper No. 22
UNITED STATES PATENT AND TRADEMARK OFFICE
____________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________
Ex parte ARMAND P. TAILLON
____________
Appeal No. 2003-0387
Application No. 09/772,275
____________
ON BRIEF
____________
Before COHEN, McQUADE, and NASE, Administrative Patent Judges.
NASE, Administrative Patent Judge.
DECISION ON APPEAL
This is a decision on appeal from the examiner's final rejection of claims 1 to 6,
which are all of the claims pending in this application.1
We REVERSE.
Appeal No. 2003-0387
Application No. 09/772,275
Page 2
2 Issued January 13, 1981.
BACKGROUND
The appellant's invention relates to "three-piece" railroad car trucks, and more
particularly to the four friction wedges that interface the bolster with the side frame and
provide suspension damping and warp stiffness (specification, p. 1). A copy of the
claims under appeal is set forth in the appendix to the appellant's brief.
Claims 1 to 6 stand rejected under 35 U.S.C. § 103 as being unpatentable over
U.S. Patent No. 4,244,2982 to Hawthorne et al. (Hawthorne).
Rather than reiterate the conflicting viewpoints advanced by the examiner and
the appellant regarding the above-noted rejection, we make reference to the answer
(Paper No. 16, mailed May 9, 2002) for the examiner's complete reasoning in support of
the rejection, and to the brief (Paper No. 11, filed January 24, 2002) and reply brief
(Paper No. 17, filed July 10, 2002) for the appellant's arguments thereagainst.
OPINION
In reaching our decision in this appeal, we have given careful consideration to
the appellant's specification and claims, to the applied prior art reference, and to the
respective positions articulated by the appellant and the examiner. Upon evaluation of
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Application No. 09/772,275
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all the evidence before us, it is our conclusion that the evidence adduced by the
examiner is insufficient to establish a prima facie case of obviousness with respect to
the claims under appeal. Accordingly, we will not sustain the examiner's rejection of
claims 1 to 6 under 35 U.S.C. § 103. Our reasoning for this determination follows.
In rejecting claims under 35 U.S.C. § 103, the examiner bears the initial burden
of presenting a prima facie case of obviousness. See In re Rijckaert, 9 F.3d 1531,
1532, 28 USPQ2d 1955, 1956 (Fed. Cir. 1993). A prima facie case of obviousness is
established by presenting evidence that would have led one of ordinary skill in the art to
combine the relevant teachings of the references to arrive at the claimed invention.
See In re Fine, 837 F.2d 1071, 1074, 5 USPQ2d 1596, 1598 (Fed. Cir. 1988) and In re
Lintner, 458 F.2d 1013, 1016, 173 USPQ 560, 562 (CCPA 1972).
The claimed subject matter
Claim 1, the only independent claim on appeal, reads as follows:
A damping system for a rail car truck having a bolster, a pair of side
frames, a plurality of friction wedges damping relative movement between the
bolster and the side frames, and a side spring supporting each friction wedge,
each friction wedge having a generally triangular shape with an angle
being
defined between a vertical friction surface and a sloping friction surface, the
angle
and the force P of each side spring being defined by the equations
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Application No. 09/772,275
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where:
FwW.E. is the required warp friction force - worn - empty;
2w is the slope warp coefficient - max;
1w is the column warp coefficient - max;
a is the bearing centers;
b is the wheelbase;
ww is the wedge [width];
Vc.[,/]W.E is the maximum compression damping force per suspension - empty;
1d is the column damping coefficient;
2d is the slope damping coefficient.
The teachings of Hawthorne
Hawthorne's invention relates to improvements in three-piece freight car truck
assemblies. In the Description of the Prior Art section, Hawthorne teaches that
In a three-piece truck assembly, the side frames and bolster normally are
square, i.e., the wheelsets and bolster (parallel to one another) are disposed
normal to the side frames. Occasionally, however, at certain car speeds, the
truck may become dynamically unstable, a phenomenon known as truck hunting,
manifested by the truck going out of square or warping. The prior art teaches
several ways of preventing truck hunting, e.g., the use of resilient side bearings,
increasing warp stiffness, steering the wheelsets, the use of conconical wheel
profiles, reducing lateral resistance, etc., and the literature has reported certain
levels of warp stiffness achieved by three-piece truck assemblies. But numerous
tests run to confirm the reported data show that warp stiffness of the levels
reported by the literature cannot be achieved with known designs of three-piece
freight car truck assemblies, and it appears that the reason for the lack of warp
stiffness is instability of the wedges within the pockets.
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Application No. 09/772,275
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Hawthorne then teaches in the SUMMARY OF THE INVENTION section that
The principal object of the present invention is to provide a wedge system
which is capable of achieving a warp stiffness high enough to elevate the critical
speed of truck hunting (the speed at which hunting will first occur) to a level
suitable for freight car operation.
Figures 1 and 2 show a typical freight car truck assembly having a pair of
laterally spaced side frames 10 carried by a pair of wheelsets 12 and spanned by a
bolster 14. Each side frame is provided with an opening 16 defined by a compression
member 18, a tension member 20, and a pair of side frame columns 22. The opposite
end portions of the bolster 14 extend respectively through the openings 16 and are
carried respectively by spring groups 24 acting against side frame spring seats. A
friction wedge 26 is carried by a spring 28 acting against the side frame spring seat to
urge the wedge upwardly between the bolster and the side frame column. As the
bolster moves vertically, the friction wedges slide against the side frame columns to
generate damping forces. Since the spring force loading a friction wedge is a function
of the spring group travel or vertical motion of the bolster, the spring force is greater
when the car is loaded than when the car is empty. Thus, the damping force varies with
the car weight.
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Application No. 09/772,275
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The usual form of the friction wedges is illustrated diagrammatically in Figure 3.
The wedge 52 has a column or friction surface 56 which frictionally engages the
opposed surface 50 of the side frame column 44. In addition, it has a surface 48
sloping at an angle
(in the order of 35 degrees relative to the column surface 56),
which surface 48 frictionally engages the opposed sloping surface 54 of a pocket 42
formed in the bolster 40. The pocket 42 accommodates the wedge 52, which is urged
upwardly between the side frame column and the bolster by the wedge spring 60, as
shown. The primary motion during truck hunting is shown in Figure 4. The side frames
10 remain parallel with each other while forming the warp angle  with the bolster 14.
Now referring particularly to Figures 3 and 5, open pockets 42 are formed at
each end of the bolster 40 respectively opposite the columns 44 of the associated side
frame. The opening into each pocket faces the adjacent side frame column. The
pocket is provided with parallel opposed sides 46, and the opposite sides 58 of the
wedge 52 are parallel thereto. In the square condition of the assembly the column
surfaces of the wedges are in full face engagement with the faces of the side frame
columns, and the sloping surfaces respectively of the bolster pockets and the wedges
are in full face engagement. When the assembly warps, the bolster assumes a position
such as that shown in Figure 6. This results in a binding between the corners of the
wedges 52 and the faces 50 of the side frame columns. The resulting forces Fc,
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Application No. 09/772,275
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spaced at distance g, produce a restoring moment of gFc. This moment increases as
the angle  increases, providing the wedges 52 remain secure in the bolster pockets
42. But certain movements of the wedges 52 within the bolster pockets 42 prevent the
warp moment gFc from becoming high enough to preclude truck hunting. These
movements may be designated: (1) Horizontal Rotation of the Wedges (Figure 7);
(2) Vertical Rotation of the Wedges (Figure 8); and (3) Unloading of the Wedges
(Figure 9).
The first undesirable moment is rotation of the wedge 52 in the bolster pocket 42
about a horizontal axis, see Figure 7. The wedge 52 rotates in the direction shown
and slips downwardly slightly in the bolster pocket 42. This permits the corner of the
wedge designated "x" to move deeper into the bolster pocket, as a consequence of
which the force Fc is reduced, which in turn reduces the warp moment, gFc, and lowers
the critical speed of truck hunting. The second undesirable movement is rotation of the
wedge 52 in the bolster pocket 42 about a vertical axis, see Figure 8. The wedge 52
rotates in the direction shown. This motion frees the static friction between the bolster
sloping surface 54 and the wedge 52, as a consequence of which the force Fc is
reduced, which also reduces the warp moment gFc. Finally, as shown in Figure 9,
under certain conditions the wedge 26 may move downwardly, in the direction of the
arrow, in the bolster pocket 38. Due to sloping surface 34 of the wedge 26, the wedge
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Application No. 09/772,275
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26 may draw back from the side frame column 22, resulting in a rapid decrease in the
force Fc, which again reduces the warp moment, gFc.
Hawthorne states (column 4, line 51+) that a parametric study was made to
assess the effect of the variables in the equations (a), (b), (c) and (d) set forth in column
4, lines 22-33) and has led to the following conclusions:
(1) With regard to the coefficient of sliding friction : Referring to FIG. 15,
although raising the value from 0.50 to 0.63 increases the ratio f for upward
motion, the point where the slip region is entered does not change appreciably.
By lowering the value to 0.10 the slip region is almost avoided. However, this is a
marginal level for practical application, i.e., it does not provide a comfortable
margin below the slip region. In the case of downward motion, lowering the value
causes higher values of negative ratio f. If these reach the region between -0.8
and -1.0, the wedge may slip downward relative to the bolster.
(2) With regard to wedge angle
: Referring to FIG. 17, decreasing the
wedge angle lowers the ratio f for upward motion, but it does not have an
appreciable effect upon entry into the slip region. The ratio f for downward
movement of the bolster is well behaved.
(3) With regard to loaded car wedge spring force Fs : Referring to FIG. 18,
for upward motion of the bolster increasing the wedge spring force lowers the
maximum ratio f and changes entry into the slip region considerably. For
downward motion, the system is well behaved.
As a result of the parametric study it was concluded that merely varying a
single parameter probably would not result in a practical system to secure the
wedges against undesirable unloading during vertical motion, and that to achieve
one purpose of this invention it probably would be necessary to vary one or more
of the parameters studied. The study suggested reducing the wedge angle

from 35 to 30 degrees, reducing the column coefficient of friction from 0.50 to the
range of 0.25 to 0.30, and increasing the empty and loaded wedge spring force
substantially.
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Application No. 09/772,275
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To reduce horizontal and vertical rotation of the wedge 52 within the pocket 42 of
the bolster 40 Hawthorne teaches (column 5, line 19+) to either (1) make a tight fit of
the wedge within the booster pocket as shown in Figure 19; (2) make the bottom of the
bolster pocket slope from each sidewall 46 of the bolster pocket toward the center of
the pocket and toward the opening into the pocket as shown in Figure 20; (3) make the
sloping surfaces of the bolster pocket and the wedge compound slopes as indicated in
connection with Figure 20; (4) partition the pocket 42a by a vertically extending wall 66
into two separate sections 68 for respectively accommodating the sections of the
wedges 52a and 52b as shown in Figure 22; (5) make the bolster pocket with sloping
sections 64a that are flat across the width thereof and which merge along the length
thereof to form a curvilinear crown 72 disposed midway between the opposed sidewalls
of the bolster pocket as shown in Figures 23-24; and (6) form the wedge
accommodating pockets 74 in the columns 78 of the side frame members while housing
the wedge springs 80 in the pockets 74 as shown in Figures 25-26.
In summary, Hawthorne teaches (column 6, lines 31-37) that his invention entails
one or more of the following: (1) reduced wedge angle
; (2) reduced coefficient of
friction ; (3) increased snubber spring force Fs; and (4) wedge and bolster pocket
arranged to preclude horizontal and vertical wedge rotation.
Appeal No. 2003-0387
Application No. 09/772,275
Page 10
3 The specification provides (e.g., page 1, first paragraph) that the present invention teaches the
desired relationship between friction wedge angle, friction coefficient, wedge spring force and wedge
width (as defined by the two equations set forth in claim 1) that provides a friction wedge that will
simultaneously produce a very high to infinite warp friction moment with a moderate to low damping force.
Ascertainment of the differences between the prior art and claim 1
After the scope and content of the prior art are determined, the differences
between the prior art and the claims at issue are to be ascertained. Graham v. John
Deere Co., 383 U.S. 1, 17-18, 148 USPQ 459, 467 (1966).
Based on our analysis and review of Hawthorne and claim 1, it is our opinion that
the only difference is the relationship between the wedge angle
and the wedge spring
force P as defined by the two equations set forth in claim 1.3 While Hawthorne does
teach a wedge angle
of 30° falling within the appellants preferred range of 28° to
about 32°, Hawthorne does not teach that the wedge spring force P would be that
defined by the two equations set forth in claim 1 when the wedge angle
was 30° and
the other variables in the two equations were determined from the rail car truck.
Similarly, while Hawthorne does disclose a wedge spring force P of 3160 lbs. falling
within the appellants preferred range of about 1350 lbs. to about 7300 lbs., Hawthorne
does not teach that the wedge angle
would be that defined by the two equations set
forth in claim 1 when the wedge spring force was 3160 lbs. and the other variables in
the two equations were determined from the rail car truck.
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Application No. 09/772,275
Page 11
In the rejection before us in this appeal, the examiner incorrectly ascertained
(answer, p. 3) that Hawthorne disclosed "all the structural limitations of the instant
claims." The examiner then stated that Hawthorne lacked "the specific simultaneous
equations recited in the claims." Hawthorne does not disclose all the structural
limitations of claim 1 since Hawthorne does not disclose any combination of wedge
angle
and wedge spring force P satisfying the two equations set forth in claim 1. That
is, claim 1 requires a specific wedge angle
with a corresponding specific wedge
spring force P which together satisfy the two equations set forth in claim 1.
Determination of obviousness
In the rejection before us in this appeal, the examiner concluded (answer, p. 4)
that it would have been obvious to a person of ordinary skill in the art at the time the
invention was made to modify Hawthorne "to optimize the wedge angle and spring force
to improve the damping characteristic as part of routine experimentation and
optimization."
In our view, the examiner is correct that it would have been obvious at the time
the invention was made to a person of ordinary skill in the art to optimize the wedge
angle and spring force in Hawthorne's freight car truck assembly. However, there is no
teachings or suggestion that optimizing the wedge angle and spring force as taught by
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Application No. 09/772,275
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Hawthorne would result in freight car truck assembly coming within the scope of claim
1. In that regard, while Hawthorne may have suggested a freight car truck assembly
having a wedge angle
of 30° and a wedge spring force P of 3160 lbs., the examiner
has not produced any rationale as to why that freight car truck assembly falls within the
scope of claim 1. The mere fact that a wedge angle
of 30° is within the range set
forth in claim 2 and a wedge spring force P of 3160 lbs. is within the range set forth in
claim 3 does not mean that when the wedge angle
is 30° and the other variables in
the two equations are determined from the rail car truck that the two equations
determine that the spring force must be 3160 lbs. Additionally, the relationship between
the wedge angle
and the wedge spring force P as defined by the two equations set
forth in claim 1 produces a new and unexpected result as explained in the briefs before
us in this appeal which is different in kind and not merely in degree from the results
suggested and taught by Hawthorne.
For the reasons set forth above, the decision of the examiner to reject claim 1,
and claims 2 to 6 dependent thereon, under 35 U.S.C. § 103 is reversed.
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Application No. 09/772,275
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CONCLUSION
To summarize, the decision of the examiner to reject claims 1 to 6 under
35 U.S.C. § 103 is reversed.
REVERSED
IRWIN CHARLES COHEN )
Administrative Patent Judge )
)
)
)
) BOARD OF PATENT
JOHN P. McQUADE ) APPEALS
Administrative Patent Judge ) AND
) INTERFERENCES
)
)
)
JEFFREY V. NASE )
Administrative Patent Judge )
Appeal No. 2003-0387
Application No. 09/772,275
Page 14
COOK, ALEX, MC FARRON, MANZO,
CUMMINGS & MEHLER, LTD.
SUITE 2850
200 WEST ADAMS STREET
CHICAGO, IL 60606
JVN/jg