Ex Parte HolderDownload PDFBoard of Patent Appeals and InterferencesMar 30, 200910954910 (B.P.A.I. Mar. 30, 2009) Copy Citation 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 Copy with citationCopy as parenthetical citation