Ex Parte Holder

Board of Patent Appeals and Interferences

Mar 30, 2009

10954910 (B.P.A.I. Mar. 30, 2009)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________________

Ex parte EATON CORPORATION
____________________

Appeal 2009-0414
Application 10/954,910
Technology Center 3600
____________________

Decided: March 30, 2009
____________________

Before JAMESON LEE, RICHARD TORCZON, and SALLY C.
MEDLEY, Administrative Patent Judges.

LEE, Administrative Patent Judge.

DECISION ON APPEAL

A. STATEMENT OF THE CASE
This is a decision on appeal by the real party in interest, Eaton
Corporation (Eaton), under 35 U.S.C. § 134(a) from a final rejection of
Appeal 2009-0414
Application 10/954,910

2
claims 1-23. Eaton requests reversal of the Examiner’s rejection of those
claims. We have jurisdiction under 35 U.S.C. § 6(b). We affirm.

References Relied on by the Examiner
Frayer 3,486,801 Dec. 30, 1969
Cook ‘198 4,260,198 Apr. 7, 1981

The Rejections on Appeal
The Examiner rejected claims 1, 2, 4-7, 9, 14-17, 22 under 35
U.S.C. § 102(b) as anticipated by Frayer.
The Examiner rejected claim 3 under 35 U.S.C. § 103(a) as
unpatentable over Frayer.
The Examiner rejected claims 8, 10-13, 18-21, and 23 under 35
U.S.C. § 103(a) as unpatentable over Frayer and Cook ‘198.

The Invention
The invention relates to hydraulic valves for use in anti-skid braking
systems for vehicles. (Spec. 1: ¶ 1.)
Claim 1 is reproduced below (Claims App’x A-1:1-20):
1. A hydraulic valve for an antiskid braking system that controls a
wheel brake of a vehicle, said hydraulic valve comprising:

a body having a supply port, return port, and a brake port for
connection to the wheel brake, the body further including a bore, a
first chamber, a second chamber, and a control chamber wherein a
supply passage is coupled to the supply port and the first chamber, a
return passage couples the return port to the bore and the control
chamber, a brake passage connects the brake port and the bore, and a
brake actuator passage opens into the bore to introduce pressurized
fluid for activating the wheel brake;
Appeal 2009-0414
Application 10/954,910

3

a valve spool, with a first end and a second end, is slideably
received within the bore with the second end exposed to pressure in
the second chamber, the valve spool having a first position at which
the brake actuator passage is in communication with the brake
passage, and a second position at which the return passage is in
communication with the brake passage, wherein the position of the
valve spool is determined by pressures in the first chamber and the
second chamber which produce forces that respectively act on the first
end and second ends of the valve spool;

an orifice providing a first fluid path between the supply
passage and the second chamber; and

a servo valve which selectively controls fluid flow between the
second chamber and the control chamber.

B. ISSUES
1. Has Eaton shown that the Examiner erred in finding that Frayer
discloses a valve spool that is received in a bore and has an end exposed to
pressure in a second chamber?
2. Has Eaton shown that the Examiner erred in finding that Frayer
discloses that the position of a valve spool is determined by pressures from
chambers at each end of the valve spool?
3. Has Eaton shown that the Examiner erred in determining that
the combined teachings of Frayer and Cook satisfy the requirement of a
valve with each of a supply port, a return port, a brake port, and a brake
valve port?
Appeal 2009-0414
Application 10/954,910

4
C. FINDINGS OF FACT
Frayer
1. Frayer discloses a brake pressure control valve for a vehicle
brake system. (Frayer 1:11-12.)
2. Pressure control valve 7 includes a valve housing 15 that
includes a fluid supply conduit 6, a return conduit 8, and a brake conduit 9.
(Frayer 2:42-47.)
3. Hydraulic fluid is supplied from a hydraulic fluid sump 2 to a
power brake valve 4 that is controlled by a foot pedal 5 operated by a vehicle
operator. (Frayer 2:35-39.)
4. The power brake valve 4 operates to regulate the amount of
hydraulic fluid supplied to a fluid conduit 6 of a pressure control valve 7.
(Frayer 2:39-43.)
5. Brake conduit 9 forms a brake port that that is connected to a
braking unit 10 by a brake actuator passage 31. (Frayer 3:45-46 and 3:17-
19.)
6. Valve housing 15 surrounds a second stage power valve 17.
(Frayer 2:65-69.)
7. Second stage valve 17 includes a pressure regulator piston 18
that is slidable within a cylinder 19. (Frayer 2:69-71.)
8. Second stage valve 17 also includes a cylinder 34 in which a
control piston 35 slides. (Frayer 3:30-32; Figure 2.)
9. “The cylinders 34 and 19 are joined together by a centrally
located opening 37 passing between the adjacent end walls of the cylinders.”
(Frayer 3:37-40.)
Appeal 2009-0414
Application 10/954,910

5
10. Frayer discloses that cylinder 39 carries a pressure and contains
a feedback and reference piston 40 and a spring 43. (Frayer 4:1-10.)
11. As disclosed in Frayer (Frayer 3:48-57):
A spring 43 located in the opposite end of the cylinder 39 from
the openisg [sic] 41 biases the piston 40 against the push rod 42
which, in turn, bears against the piston 18 to urge it against the
push rod 38, which in turn, bears against the piston 35 and
urges it toward the piston stop 36. Thus, it may be seen that the
pistons 18, 35 and 40 are all in axial alignment with each other
and are all biased in the same direction by the spring 43.

12. “[T]he forces acting to move the cylinder 18 come from either
the control piston 35 or the feed-back and reference piston 40 [that] is biased
by the spring 43.” (Frayer 4:2-5.)
13. “The pressure differential between each end of the cylinder 34
determines the force which the piston [35] will exert and when there is an
unbalance in pressure in the passages 32 and 33, the piston 35 will move in
one direction or the other depending upon which passage carries the highest
pressure.” (Frayer 4:16-23):
14. Also in Frayer (Frayer 4:23-28):
In order to move the piston 35 to the right, the pressure in the
passage 32 must be greater than the pressure 33 and this
pressure differential will cause a force to be exerted on rod 37
and valve piston 18. This first stage driving force will be
balanced by the pressure differential force on piston 40 and the
less significant spring force.

Cook ‘198
15. Cook ‘198 discloses a skid control valve 10 that includes each
of a supply port 28, a return port 55, a brake port 51, and a metered pressure
input port 43. (Cook ‘198 Figure 1.)
Appeal 2009-0414
Application 10/954,910

6
16. Supply port 28 receives a substantially constant pressure from a
constant pressure source. (Cook ‘198 2:60-63.)
17. As described in Cook ‘198, a two stage skid control valve
includes a constant supply port and a separate metered brake valve port.
(Cook ‘198 1:19-20.)
18. In the first stage, a constant supply pressure is provided to a
supply port to generate a control signal. (Cook ‘198 1:20-22.)
19. In the second stage, pressure supplied to a brake port is
determined in response to a pressure difference between the control pressure
and a metered supply pressure supplied to the brake valve port. (Cook ‘198
1:22-27.)
20. That configuration desirably “allows the control pressure to be
independent of the metered supply pressure variations under normal skid
control operating conditions.” (Cook ‘198 1:27-34.)
21. In describing the benefits of its two stage control valve, Cook
‘198 refers to a commonly owned prior patent, U.S. Pat. No. 4,130,322, also
to Cook (Cook ‘322). (Cook ‘198 1:10-34.)
Cook ‘322
22. Cook ‘322 discloses that vehicle skid control valves that have a
single metered pressure input suffer a disadvantage of “having a different
pressure control-signal level relationship for a given metered pressure input.
That is, the brake pressure output in the skid control mode of operation
would depend upon the control signal level as well as the input metered
pressure.” (Cook ‘322 1:42-45.)
23. The sensitivity to the input metered pressure results in a “skid
control effectiveness [that] is diminished because of the effect variation of
Appeal 2009-0414
Application 10/954,910

7
input metered pressure has upon the brake pressure applied in response to a
particular control input signal.” (Cook ‘322 1:49-52.)
D. PRINCIPLES OF LAW
During examination, claim terms are given their broadest reasonable
interpretation consistent with the specification. In re Sneed, 710 F.2d 1544,
1548 (Fed. Cir. 1983).
“Although operational characteristics of an apparatus may be apparent
from the specification, we will not read such characteristics into the claims
when they cannot be fairly connected to the structure recited in the claims.”
In re Hiniker Co., 150 F.3d 1362, 1368 (Fed. Cir. 1998).
It is not necessary that the inventions of the references be physically
combinable, without change, to render obvious the invention under review.
In re Sneed, 710 F.2d at 1550. In particular, “[t]he test for obviousness is
not whether the features of a secondary reference may be bodily
incorporated into the structure of the primary reference; nor is it that the
claimed invention must be expressly suggested in any one or all of the
references. Rather, the test is what the combined teachings of the references
would have suggested to those of ordinary skill in the art.” In re Keller, 642
F.2d 413, 425 (CCPA 1981).
A person of ordinary skill in the art is a person of ordinary creativity,
not an automaton. KSR Int’l Co. v. Teleflex Inc., 127 S.Ct. 1727, 1742
(2007).
E. ANALYSIS
The Examiner rejected Eaton’s claims based on three grounds of
rejection. Eaton argues each ground separately.
Appeal 2009-0414
Application 10/954,910

8
The anticipation rejection
The Examiner rejected claims 1, 2, 4-7, 9, 14-17, and 22 as
anticipated by Frayer. Eaton argues the merits of the rejection of each of
claims 1, 7, 14, and 15. The remaining dependent claims 2, 4-6, 9, 16, 17,
and 22 are not separately argued. We address the rejections of claims 1, 7,
14, and 15.
Claim 1
With regard to claim 1, Eaton first disputes that Frayer satisfies the
requirement of a valve spool that is “slideably [sic] received in a bore and
that has a second end exposed to pressure in the second chamber.” (Claims
App’x A-1:9-10.)
The Examiner found that in Frayer, “valve spool” 46 is slidably
received within a bore and has a second end exposed to pressure in “second
chamber” 34. (Ans. 3:14-15.)
Eaton argues that pressure in “second chamber” 34 does not act on an
end of “valve spool” 46. Rather, according to Eaton, the pressure in “second
chamber” 34 acts on control piston 35, which cannot be considered part of
the valve spool because “it is in a separate bore 34 from the bore 19 in which
the valve spool 46 slides.” (App. Br. 7:4-8.)
Eaton’s argument is not persuasive. As identified by Eaton in its
Appeal Brief, the “valve spool” of claim 1 corresponds to the valve spool
132 and pressure compensation piston 134 identified in the specification.
(App. Br. 3:13-14; 7:9-11.) As shown in Eaton’s Figure 4, element 132 lies
in a narrow passage within valve 130 and element 134 lies in an adjacent
passage with a larger diameter. According to Eaton, those two adjacent
Appeal 2009-0414
Application 10/954,910

9
passages together form a “bore.” (App. Br. 7:9-11.) During examination,
claim terms are given their broadest reasonable interpretation consistent with
the specification. In re Sneed, 710 F.2d at 1548.
In the context of Eaton’s specification, a “bore” need not mean a
single passage of uniform diameter. Rather, it is consistent with the
specification that a “bore” can include adjacent passages of varying
diameter. Frayer discloses a brake pressure control valve for a vehicle brake
system. (Frayer 1:11-12.) In Frayer, valve 7 includes a valve housing 15
surrounding a second stage power valve 17. (Frayer 2:65-69.) Second stage
valve 17 includes a pressure regulator piston 18 that is slidable within a
cylinder 19. (Frayer 2:69-71.) Element 46 is a center shaft portion of
piston 18. (Frayer 3:65-66.) Second stage valve 17 also includes a cylinder
34 in which a control piston 35 slides. (Frayer 3:30-32; Figure 2.) Frayer
discloses that “[t]he cylinders 34 and 19 are joined together by a centrally
located opening 37 passing between the adjacent end walls of the cylinders.”
(Frayer 3:37-40.) That is, cylinders 34 and 19, and opening 37 are adjacent,
connected passages. Those passages form a bore.
We therefore reject Eaton’s argument that the Frayer’s “valve
spool” 46 and control piston 35 are in separate bores. As discussed above,
Frayer’s piston 18 (with center shaft 46) and control piston 35 slide within
the same bore.
Furthermore, as identified by the Examiner (Ans. 3:8-9), cylinder 34
forms a second chamber within the bore. The ends of control piston 35 are
exposed to pressure within that second chamber (Frayer 3:33-36.) We also
reject Eaton’s argument that Frayer does not satisfy the requirement of a
Appeal 2009-0414
Application 10/954,910

10
valve spool that “has a second end exposed to pressure in the second
chamber.”
With further regard to claim 1, Eaton argues that Frayer does not
satisfy the requirement that the “position of the valve spool is determined by
pressures in the first chamber and the second chamber which produce forces
that respectively act on the first and second ends of the valve spool.”
According to Eaton (App. Br. 7:12-16):
Even if Frayer's remotely located control piston 35 is considered as
part of the valve spool 46, pressure in second chamber 34 does not act
on the end of that combined structure, but rather acts on an
intermediate surface. Furthermore, pressures in the first chamber 39
and the second chamber 34 produce motion of the valve spool only in
one direction, i.e. to the left in Figure 2, which is the same direction as
the force of spring 43.

Evidently, Eaton contends that “second chamber 34” relied upon by
the Examiner is formed only to the right side of control piston 35. However,
page 4 of the Examiner’s Answer includes an annotated copy of Frayer’s
Figure 2 clearly designating the pressurized area to the left of piston 35 as a
second chamber.
Furthermore, as disclosed in Frayer (Frayer 4:16-23):
The pressure differential between each end of the cylinder 34
determines the force which the piston [35] will exert and when there is
an unbalance in pressure in the passages 32 and 33, the piston 35 will
move in one direction or the other depending upon which passage
carries the highest pressure.

That is, in Frayer pressurized chambers exist on both the left and the right of
piston 35.
The Examiner also identified that the claimed “first chamber” is
satisfied by Frayer’s cylinder 39. (Ans. 3:8.) Frayer discloses that cylinder
Appeal 2009-0414
Application 10/954,910

11
39 carries a pressure and contains a feedback and reference piston 40 and a
spring 43. (Frayer 4:1-10.) As described in Frayer, “the forces acting to
move the cylinder 18 come from either the control piston 35 or the feed-back
and reference piston 40 [that] is biased by the spring 43.” (Frayer 4:2-5.)
Frayer also discloses that (Frayer 4:22-28):
In order to move the piston 35 to the right, the pressure in the passage
32 must be greater than the pressure 33 and this pressure differential
will cause a force to be exerted on rod 37 and valve piston 18. This
first stage driving force will be balanced by the pressure differential
force on piston 40 and the less significant spring force.

Thus, forces produced by pressures in each of cylinders 34 and 39
operate to determine the position of piston 35 and piston 18 within the valve.
We reject Eaton’s argument that “pressures in the first chamber 39 and the
second chamber 34 produce motion of the valve spool only in one
direction.” Eaton has not shown that the Examiner erred in finding that
Frayer satisfies the limitation that the position of the valve spool is
“determined by pressures in the first chamber and the second chamber which
produce forces that respectively act on the first and the second ends of the
valve spool.”
Claim 7
Claim 7 is dependent on claim 1 and adds the limitation “wherein the
brake actuator passage is connected to a brake valve port in the body.”
Eaton disputes that Frayer anticipates claim 7. Eaton contends that the
“brake valve port” limitation introduces a “fourth port” requirement while
Frayer discloses only three ports 6, 8, and 9. (App. Br. 8:1-4.)
Appeal 2009-0414
Application 10/954,910

12
Eaton’s argument is misplaced. Claim 7 does not call for a “fourth
port” or require an additional port. Rather, the claim simply requires that
“the brake actuator passage [is] connected to a brake valve port in the body.”
Eaton’s specification discloses that brake valve port 70 is a port
within a valve body 42 that is connected to brake valve 14 that controls the
flow of hydraulic fluid to the valve body from a supply line 16. (Spec. 5:
¶14; 6: ¶17; Figure 1.) That is, according to Eaton’s specification, a brake
valve port is also a supply port for hydraulic fluid.
The Examiner determined that Frayer’s fluid conduit 6 satisfies the
requirement in claim 1 of a supply port in a valve body 15. (Ans. 3:6.) In
Frayer, hydraulic fluid is supplied from a hydraulic fluid sump 2 to a power
brake valve 4 that is controlled by a foot pedal 5 operated by a vehicle
operator. (Frayer 2:35-39.) The power brake valve 4 operates to regulate
the amount of hydraulic fluid supplied to fluid conduit 6 dependent upon the
position of brake pedal 5. (Frayer 2:39-43.) Thus, fluid conduit 6 acts as a
port receiving a fluid supply from brake valve 4. It is neither unreasonable
nor inconsistent with Eaton’s specification to regard fluid conduit 6 as both a
supply port and a brake valve port.
Furthermore, Frayer’s brake conduit 9 forms a brake port that that is
connected to a braking unit 10 by a brake actuator passage 31. (Frayer 3:45-
46 and 3:17-19.) As shown in Frayer’s Figure 1, brake valve port 6 is
fluidly connected to brake actuator 31.
Accordingly, we reject Eaton’s argument that Frayer does not satisfy
the requirement in claim 7 that “the brake actuator passage is connected to a
brake valve port in the body.”
Appeal 2009-0414
Application 10/954,910

13
Claim 14
Claim 14 is independent and is reproduced below (Claims App’x A-4:
10- A-5:8):
14. A hydraulic valve for an antiskid braking system that controls a
wheel brake of a vehicle in response to user operation of an actuation
device, said hydraulic valve comprising:

a body having a supply port, return port, and a brake port for
connection to the wheel brake, the body further including a bore, a
first chamber and a control chamber wherein a supply passage couples
the supply port to the bore and to the first chamber, a return passage
couples the return port to the bore and the control chamber, and a
brake passage couples the brake port to the bore;

a valve spool has a first end and a second end and is slideably
received within the bore, the valve spool having a first position at
which the brake actuator passage is coupled to the brake passage, and
a second position at which the return passage is coupled to the brake
passage;

an orifice providing a first fluid path between the supply port
and a second chamber located in the bore at the second end of the
valve spool;

a piston engaging the first end of the valve spool in response to
pressure in the first chamber;

a nozzle having an inlet connected to the second chamber and
having an outlet that opens into the control chamber; and

a servo valve having a flapper which selectively engages and
disengages the outlet to control flow of fluid through the nozzle.

Eaton first disputes that Frayer satisfies the requirement of “a second
chamber located in the bore at the second end of the valve spool.” Eaton
Appeal 2009-0414
Application 10/954,910

14
contends that the portion of cylinder 34 that the Examiner relies upon as a
second chamber is in a separate bore from “valve spool” 46.
For reasons similar to those above, we reject Eaton’s argument.
Cylinders 34 and 19 collectively form a bore. Pressure regulator piston 18
and control piston 35 form a valve spool that lies within the bore. The
“second chamber” within cylinder 34 to the left of control piston 35 as
shown in Figure 1 satisfies the requirement of a “second chamber located in
the bore at the second end of the valve spool.”
Eaton also disputes that Frayer satisfies the requirement of “a piston
engaging the first end of the valve spool in response to pressure in the first
chamber.” According to Eaton, “[t]he corresponding piston 40 in Frayer
neither engages the valve spool nor does so in response to pressure in the
first chamber 39.” (App. Br. 8:10-11.)
Eaton’s arguments are not well supported. We first reject Eaton’s
argument that piston 40 does not “engage” the valve spool formed by pistons
18 and 35. Eaton’s claim does not require that the piston directly engage or
contact the valve spool. Frayer’s piston 40 contacts a push rod 42 that, in
turn, contacts “valve spool” 18 and 35. (Frayer 3:51-53; Figure 2.) Piston
40 “engages” the valve spool through contact with push rod 42.
We turn now to Eaton’s argument that Frayer’s piston 40 does not
engage the valve spool “in response to pressure in the first chamber” 39.
Eaton argues that (App. Br. 8:16-21):
Furthermore, a spring 43 applies a force which keeps the piston 40 in
engagement with the push rod 42 and in turn the push rod 42 in
engagement with the valve spool 46 regardless of pressure in the first
chamber. Although the first chamber pressure acts on the piston 40,
such pressure does not produce a response from the piston which
causes that engagement. Whereas in [the] present invention, piston 50
Appeal 2009-0414
Application 10/954,910

15
in Figure 4 is not acted upon by the spring 56, which directly engages
the valve spool 132. As a consequence, the valve spool and the piston
50 are able to move away from each other, in which case an increase
of pressure in the first chamber 52 brings them back into engagement.

Evidently, according to Eaton, the limitation of a piston that engages
the valve spool “in response to pressure in the first chamber” means that the
piston is not contacted by a spring such that piston and valve spool can
separate as with the valve spool 132 and piston 50 illustrated in Figure 4 of
the specification. However, “[a]lthough operational characteristics of an
apparatus may be apparent from the specification, we will not read such
characteristics into the claims when they cannot be fairly connected to the
structure recited in the claims.” In re Hiniker Co., 150 F.3d at 1368.
Here, that the valve spool 132 and piston 50 in one embodiment of the
Appellant’s specification are configured in a manner that allows for
separation is of no moment. Claim 14 does not prohibit a spring that
contacts the piston nor require that the piston and valve spool need separate.
All that the claim requires is engagement of the piston with the valve spool
“in response to pressure in the first chamber.”
As we have already noted, Frayer discloses that (Frayer 4:22-28):
In order to move the piston 35 to the right, the pressure in the passage
32 must be greater than the pressure 33 and this pressure differential
will cause a force to be exerted on rod 37 and valve piston 18. This
first stage driving force will be balanced by the pressure differential
force on piston 40 and the less significant spring force.

Frayer also discloses that piston 40 is biased against push rod 42,
which then “bears against the piston 18.” (Frayer 3:51-53.) Thus, as a
balancing force to pressures applied to piston 35 that move the piston to the
right, a “pressure differential force” and a spring force act on piston 40. A
Appeal 2009-0414
Application 10/954,910

16
person of ordinary skill in the art would have recognized from that teaching
that both a “pressure differential force” and a spring force applied to piston
40 in cylinder 39 act to bias that piston against piston 18 via push rod 42.
In light of those teachings of Frayer, the Examiner determined that the
limitation of a piston that engages the valve spool “in response to pressure in
the first chamber” is satisfied. We reject Eaton’s argument that Frayer does
not satisfy that limitation.
Moreover, even if only the force of spring 43 acts on piston 40 to
ultimately bias it against piston 18, the limitation of claim 14 is still
satisfied. “Pressure” means “the application of force to something else in
direct contact with it.” Merriam Webster’s Collegiate Dictionary 923 (10th
ed. 1996). Spring 43 resides in cylinder 39 and applies a biasing force to
piston 40. That is, the pressure supplied by spring 43 is in “first chamber”
39 and acts to bias piston 40 and pushrod 42 against a first end of “valve
spool” 18 and 35.
For the foregoing reasons, Eaton has not shown that the Examiner
erred in determining that Frayer satisfies the requirements of claim 14.
Claim 15
Claim 15 is dependent on claim 14 and adds the limitation of “a
spring biasing the first end of the valve spool with respect to the body.”
(Claims App’x A-5:9-10.) The Examiner found that limitation satisfied by
the operation of Frayer’s spring 43. (Ans. 6:8-10.)
Eaton disputes that Frayer satisfies claim 15, arguing that spring 43
only biases piston 40. Evidently, Eaton contends that Frayer’s spring 43
does not bias the valve spool formed by pressure regulator piston 18 and
control piston 35 because the spring does not directly contact piston 18.
Appeal 2009-0414
Application 10/954,910

17
Eaton’s argument is not persuasive. Claim 15 does not require that
the spring contact or directly engage the valve spool. Rather, the spring
must merely bias the first end of the valve spool. Frayer discloses (Frayer
3:48-57):
A spring 43 located in the opposite end of the cylinder 39 from the
openisg [sic] 41 biases the piston 40 against the push rod 42 which, in
turn, bears against the piston 18 to urge it against the push rod 38,
which in turn, bears against the piston 35 and urges it toward the
piston stop 36. Thus, it may be seen that the pistons 18, 35 and 40 are
all in axial alignment with each other and are all biased in the same
direction by the spring 43.

Thus, spring 43 biases pistons 18 and 35. We reject Eaton’s argument
that Frayer does not satisfy claim 15.
For all the foregoing reasons, we sustain the rejection of claims 1, 2,
4-7, 9, 14-17, and 22 under 35 U.S.C. § 102(b) as anticipated by Frayer.
The obviousness rejection of claim 3
Claim 3 is dependent on claim 1 and adds the limitation “a spring
biasing the first end of the valve spool with respect to the body.” (Claims
App’x A-2:4-5.) The Examiner rejected claim 3 under 35 U.S.C. § 103(a) as
unpatentable over Frayer.
As with claim 15, Eaton argues that the limitation requires a spring
that directly contacts the valve spool. For the same reasons given above
with respect to claim 15, we reject Eaton’s argument that Frayer does not
satisfy the requirements of claim 3.
We sustain the rejection of claim 3 under 35 U.S.C. § 103(a) as
unpatentable over Frayer.
Appeal 2009-0414
Application 10/954,910

18
The obviousness rejection of claims 8, 10-13, 18-21, and 23
The Examiner rejected claims 8, 10-13, 18-21, and 23 under 35
U.S.C. § 103(a) as unpatentable over Frayer and Cook ‘198.
Eaton argues claims 8, 10-13, 18-21, and 23 collectively. Eaton
contends that each of those claims require four separate ports, namely a
supply port, a return port, a brake valve port, and a brake port. Claim 10 is
representative and is reproduced below (Claims App’x A-3:4-21):
10. A hydraulic valve for an antiskid braking system that controls a
wheel brake of a vehicle in response to user operation of an actuation
device, said hydraulic valve comprising:

a body having a supply port, return port, a brake valve port that
receives pressure from the actuation device, and a brake port for
connection to the wheel brake, the body further including a bore, a
first chamber and a control chamber wherein a supply passage extends
between the supply port and the first chamber, a return passage
couples the return port to the bore and to the control chamber, a brake
actuator passage connects the brake valve port to the bore, and a brake
passage couples the brake port to the bore;

a valve spool has a first end and a second end and is slideably
received within the bore, the valve spool having a first position at
which the brake actuator passage is coupled to the brake passage, and
a second position at which the return passage is coupled to the brake
passage;

a piston exposed to pressure in the first chamber and in
response to that pressure engages the first end of the valve spool;

an orifice providing a first fluid path between the supply port
and a second chamber located in the bore at the second end of the
valve spool;

a nozzle having an inlet connected to the second chamber and
having an outlet that opens into the control chamber; and
Appeal 2009-0414
Application 10/954,910

19

a servo valve having a flapper which selectively engages and
disengages the outlet to control flow of fluid through the nozzle.

The Examiner found that Frayer discloses all the limitations of claim
10 with the exception of each of a brake valve port and a supply port.
According to the Examiner, Frayer shows a single port that operates as a
supply port and a brake valve port. (Final Rej.1 3:16-17) To remedy the
deficiency, the Examiner pointed to Cook ‘198 and determined that (Final
Rej. 3:17-21):
Cook[‘198] teaches the use of separate brake valve 45 and supply
ports 32. It would have been obvious to one of ordinary skill in the art
at the time the invention was made to have a brake valve port and
supply port as taught by Cook[‘198] in the device of Frayer in order to
have a comparison pressure to limit the pressure appl[ied] by the
brake valve (see abstract of Cook[‘198]).

Eaton disputes that there is adequate motivation to combine the
teachings of Frayer and Cook ‘198. Eaton contends that (App. Br. 10:
The dramatically different manner in which the components in
Frayer and Cook[‘198] are connected fail to guide one of ordinary
skill in the art as to why, how or where to add a separate supply port
to the Frayer valve assembly. Other than both patents relating to brake
control valves that have a spool valve and a flapper-type servo valve,
the internal connection of those components in each patent differs so
dramatically that it is not obvious to combine their teachings in the
manner stated in the Office Action.

Eaton’s argument is not persuasive. It is not necessary that the
inventions of the references be physically combinable, without change, to
render obvious the invention under review. In re Sneed, 710 F.2d at 1550.

1 Final Rejection mailed August 24, 2006.
Appeal 2009-0414
Application 10/954,910

20
In particular, “[t]he test for obviousness is not whether the features of a
secondary reference may be bodily incorporated into the structure of the
primary reference; nor is it that the claimed invention must be expressly
suggested in any one or all of the references. Rather, the test is what the
combined teachings of the references would have suggested to those of
ordinary skill in the art.” In re Keller, 642 F.2d at 425.
Here, whether a person of ordinary skill in the art would have taken
the ports as they appear in Cook ‘198 and physically combined them with
the valve body of Frayer is not the relevant inquiry in resolving the
obviousness question. Instead, the question of obviousness centers on what
the combined teachings would have suggested to a person of ordinary skill
in the art.
Cook ‘198 discloses a skid control valve 10 that includes each of a
supply port 28, a return port 55, a brake port 51, and a metered pressure
input port 43 that corresponds to the claim brake valve port. Supply port 28
receives a substantially constant pressure from a constant pressure source.
(Cook ‘198 2:60-63.) As described in Cook ‘198, a two stage skid control
valve includes a constant supply port and a separate metered brake valve
port. (Cook ‘198 1:19-20.) In the first stage, a constant supply pressure is
provided to a supply port to generate a control signal. (Cook ‘198 1:20-22.)
In the second stage, pressure supplied to a brake port is determined in
response to a pressure difference between the control pressure and a metered
supply pressure supplied to a separate brake valve port. (Cook ‘198 1:22-
27.) That configuration desirably “allows the control pressure to be
independent of the metered supply pressure variations under normal skid
control operating conditions.” (Cook ‘198 1:27-34.)
Appeal 2009-0414
Application 10/954,910

21
In describing the benefits of its two stage control valve, Cook ‘198
refers to a commonly owned prior patent, U.S. Pat. No. 4,130,322, also to
Cook (Cook ‘322). (Cook ‘198 1:10-34.) Extrinsic evidence may be
considered to explain the meaning of a prior art teaching. In re Baxter
Travenol Labs., 952 F.2d 388, 390 (Fed. Cir. 1991). We look to Cook ‘322
for an explanation as to why it is desirable that a control pressure be
independent of a metered supply pressure.
Cook ‘322 discloses that vehicle skid control valves that have a single
metered pressure input suffer a disadvantage. The disadvantage is that of
“having a different pressure control-signal level relationship for a given
metered pressure input. That is, the brake pressure output in the skid control
mode of operation would depend upon the control signal level as well as the
input metered pressure.” (Cook ‘322 1:42-45.) The sensitivity to the input
metered pressure results in a “skid control effectiveness [that] is diminished
because of the effect variation of input metered pressure has upon the brake
pressure applied in response to a particular control input signal.” (Cook
‘322 1:49-52.)
Thus, at the time of Eaton’s invention, a person of ordinary skill
would have recognized that skid control valves having only a single metered
supply port, i.e. a brake valve port, are disadvantageous. Frayer discloses
such a skid control valve with a single supply port 6 that receives a
pressurized fluid that is metered by brake valve 4 which is controlled by
brake pedal 5. (Frayer 2:35-43.) In light of the combined teachings of
Frayer and Cook ‘198, one with ordinary skill in the art would have
modified Frayer to incorporate a constant supply port that is separate from a
metered brake valve port in order to have constant and metered pressurized
Appeal 2009-0414
Application 10/954,910

22
fluid flows that are independent of one another. The level of ordinary skill
in the skid control valve art is such that one with ordinary skill would have
addressed routine valve design concerns necessary to accomplish separate
supply ports for the delivery of the separate pressure flows to the valve. One
of ordinary skill in the art is a person of ordinary creativity, and not an
automaton. KSR Int’l Co., 127 S.Ct. at 1742.
For the foregoing reasons, we reject Eaton’s argument that a person of
ordinary skill in the art would not have had adequate motivation to combine
the teachings of Frayer and Cook ‘198. We sustain the rejection of claims 8,
10-13, 18-21, and 23 under 35 U.S.C. § 103(a) as unpatentable over Frayer
and Cook ‘198.
F. CONCLUSION
1. Eaton has not shown that the Examiner erred in finding that
Frayer discloses a valve spool that is received in a bore and has an end
exposed to pressure in a second chamber.
2. Eaton has not shown that the Examiner erred in finding that
Frayer discloses that the position of a valve spool is determined by pressures
from chambers at each end of the valve spool.
3. Eaton has not shown that the Examiner erred in determining
that the combined teachings of Frayer and Cook satisfy the requirement of a
valve with each of a supply port, a return port, a brake port, and a brake
valve port.
G. ORDER
The Examiner rejection of claims 1, 2, 4-7, 9, 14-17, 22 under 35
U.S.C. § 102(b) as anticipated by Frayer is affirmed.
Appeal 2009-0414
Application 10/954,910

23
The Examiner rejected claim 3 under 35 U.S.C. § 103(a) as
unpatentable over Frayer is affirmed.
The Examiner rejected claims 8, 10-13, 18-21, and 23 under 35
U.S.C. § 103(a) as unpatentable over Frayer and Cook ‘198 is affirmed.

AFFIRMED

ack

cc:

Marvin Union
Eaton Corporation
Eaton Center
1111 Superior Ave.
Cleveland OH 44114-2584