Ex Parte Chico et alDownload PDFBoard of Patent Appeals and InterferencesFeb 24, 200910853267 (B.P.A.I. Feb. 24, 2009) Copy Citation UNITED STATES PATENT AND TRADEMARK OFFICE ____________ BEFORE THE BOARD OF PATENT APPEALS AND INTERFERENCES ____________ Ex parte PHILIPPE CHICO and PIERRE GIROD ____________ Appeal 2008-2432 Application 10/853,267 Technology Center 3600 ____________ Decided:1 February 24, 2009 ____________ Before LINDA E. HORNER, JOHN C. KERINS, and MICHAEL W. O’NEILL, Administrative Patent Judges. HORNER, Administrative Patent Judge DECISION ON APPEAL 1 The two month time period for filing an appeal or commencing a civil action, as recited in 37 C.F.R. § 1.304, begins to run from the decided date shown on this page of the decision. The time period does not run from the Mail Date (paper delivery) or Notification Date (electronic delivery). Appeal 2008-2432 Application 10/853,267 2 STATEMENT OF THE CASE Philippe Chico and Pierre Girod (Appellants) seek our review under 35 U.S.C. § 134 of the final rejection of claims 1-12. We have jurisdiction under 35 U.S.C. § 6(b) (2002). SUMMARY OF DECISION We AFFIRM. THE INVENTION The Appellants’ claimed invention is to a method of controlling an electromechanical aircraft brake. Spec. 1:3-4. Aircraft brakes use a stack of rotating disks (rotors) and stationary disks (stators) and a presser member to press against the stack to cause braking by friction between the rotors and stators. Spec. 1:6-12. Hydraulic aircraft brakes use pistons mounted on a ring to press it against the stack of disks under drive from hydraulic fluid under pressure. Spec. 1:13-17. Electromechanical aircraft brakes use a pusher, which is displaced by an electric motor and a converter, to engage the disk stack. Spec. 2:11-18. As the disks in the brake stack wear, the resting position of the pusher is adjusted by turning the electric motor so that the pusher is maintained close to the stack of disks. Spec. 2:30-36. The Appellants state that the object of their invention is “to propose a method of controlling electromechanical brakes that take[s] advantage of the possibilities made available by such technology to obtain new and advantageous functions that are not available with hydraulic technology.” Spec. 3:10-14. In particular, the Appellants’ claimed invention uses the Appeal 2008-2432 Application 10/853,267 3 same electric motor that is used to adjust the pusher toward the stack of disks to also reverse the position of the pusher away from the stack of disks. Spec. 3:30-37. Claim 1, reproduced below [paragraphing added], is representative of the subject matter on appeal. 1. A method of controlling an electromechanical aircraft brake comprising a stack of disks and a ring carrying a plurality of electromechanical actuators each fitted with a pusher that is movable in register with the stack of disks under drive from an associated electric motor so that rotation of the motor in a first direction causes the pusher to be pressed against the stack of disks, the method comprising the step of causing at least one motor to rotate in a second direction opposite to the first direction so as to cause the corresponding pusher to reverse beyond a distance corresponding to normal operating clearance between the pusher and the stack of disks. THE REJECTION The Appellants seek review of the Examiner’s rejection of claims 1-12 under 35 U.S.C. § 103(a) as unpatentable over U.S. Patent No. 6,471,015 B1 to Ralea et al., issued October 29, 2002 (Ralea) and U.S. Patent No. 6,293,370 B1 to McCann et al., issued September 25, 2001 (McCann). Appeal 2008-2432 Application 10/853,267 4 ISSUE The Examiner found that Ralea discloses the claimed method of controlling an electromechanical aircraft brake except that it lacks a specific disclosure of reversing the actuating motors. Ans. 3. The Examiner found that McCann teaches a disc brake capable of compensating for wear of the brake linings and teaches reversing an electric motor 40 when the brake lining requires changing. Ans. 3-4. The Examiner determined it would have been obvious to use reversible actuators/motors in Ralea “to make replacement of the brake disc stack and subsequent readjustment of the brakes easier.” Ans. 4. The Appellants contend there is no reason to consider the motor of McCann or its operation for use with a pusher in a stacked disk-type brake for driving a pusher in both a braking and a retracting direction. Br. 17. The issue presented by this appeal is: Have the Appellants shown the Examiner erred in determining that the claimed method of controlling an electromechanical aircraft brake would have been obvious in view of the combined teachings of Ralea and McCann? FINDINGS OF FACT We find that the following enumerated findings are supported by at least a preponderance of the evidence. Ethicon, Inc. v. Quigg, 849 F.2d 1422, 1427 (Fed. Cir. 1988) (explaining the general evidentiary standard for proceedings before the Office). Appeal 2008-2432 Application 10/853,267 5 1. The Appellants’ Specification describes that “[i]n order to ensure that the brake has a very fast reaction speed, the pushers 8 are maintained close to the stack of disks while the brake is not in action, at a distance d corresponding to normal operating clearance, which in practice is of the order of a few millimeters.” Spec. 6:23-27. 2. The Appellants’ Specification describes that when maintenance is performed on the brake, “at least one of the motors is powered so as to cause it to rotate in the second direction, thereby causing the corresponding pusher to reverse through a distance l (of the order of several tens of millimeters), that is sufficient to enable the stack of worn disks to be replaced by a thicker stack of new disks.” Spec. 7:16-23; Fig. 2. 3. Ralea discloses an electromechanical brake assembly comprising a brake disk stack, a housing 147 including a guideway 165, a ram nut 163 guided by the guideway 165 for movement of an actuator ram 135 toward and away from the brake disk stack, a lead screw 162 in threaded engagement with the ram nut 163 whereupon rotation of the lead screw 162 effects linear movement of the ram nut 163 for selective movement of the actuator ram 135 into and out of forceful engagement with the brake disk stack for applying and releasing braking force on a rotatable wheel; and an electric motor 150 drivingly connected to the lead screw gear for rotating the lead screw to effect movement of the ram nut and actuator ram Appeal 2008-2432 Application 10/853,267 6 toward and away from the brake disk stack. Ralea, col. 4, ll. 10- 22; col. 9, l. 58 – col. 10, l. 50; col. 11, ll. 14-19; Figs 12-15. Ralea further discloses a plurality of motors 150 and a corresponding plurality of actuators 127 each having a ram 135, wherein the actuators are mounted about four respective quadrants of the housing 147. Ralea, col. 9, ll. 58-64; Fig. 11. 4. As such, Ralea discloses that the motor 150 is used to both advance and retract the ram 135 toward and away from the brake disk stack. 5. Ralea discloses a brake wear measurement routine in which brake wear is determined by comparing a present brake disk stack height to a reference brake disk stack height. Ralea, col. 2, ll. 53-63. 6. Ralea discloses that the reference brake disk stack height is obtained by displacing the reciprocating ram to load a new brake disk stack by a predetermined amount and using a position sensor to measure the displacement of the reciprocating ram to the brake disk stack. Ralea, col. 3, ll. 38-47. 7. Ralea discloses that the present brake disk stack height is measured by displacing the reciprocating ram to load the brake disk stack by a predetermined amount and using a position sensor to measure a present displacement value of the ram. Ralea, col. 3, ll. 14-22. 8. Ralea also discloses a running clearance adjustment routine in which a present displacement value of the reciprocating ram is obtained and using this value to determining a running clearance Appeal 2008-2432 Application 10/853,267 7 position of the ram by subtracting the predetermined clearance value from the present displacement value to obtain a new running clearance value, and using this new value to determine the running clearance position of the ram. Ralea, col. 3, ll. 48-67. 9. In other words, Ralea advances the ram to engage the brake disk stack to obtain a present displacement value and then retracts the ram by a predetermined clearance value so that the resting position of the ram is always maintained a certain distance away from the brake disk stack as the brake disk stack wears during use. 10. Ralea does not explicitly disclose that the motor can be used to retract the actuator ram a distance greater than the running clearance distance. 11. It was known in the art of electromechanical braking that worn disks are replaced by a new disk stack. Spec. 1:29-30. 12. McCann discloses the use of an electric motor within a brake to control the brake running clearance and to enable brake “de- adjustment.” McCann, col. 1, ll. 5-8. 13. In other words, McCann discloses using the same electric motor to advance the brake-applying piston so as to adjust the running clearance as the brake linings wear during use and to retract the brake-applying piston when the brake linings need to be replaced: In a brake having an electric motor adapted to perform the adjustment operation, de-adjustment can also be enabled automatically through use of the same motor. De-adjustment is required when it Appeal 2008-2432 Application 10/853,267 8 has been determined that the brake linings require replacement. In a conventional brake, the adjuster mechanism has to be manually unwound so as to retract the brake-applying piston away from the brake rotor. This enables the old linings to be removed and replaced with new linings. In the implementation having an electric motor, a simple electrical signal from a brake-associated switch, either mounted on the brake or electrically connected thereto, can be used to instigate retraction of the brake applying member.” McCann, col. 2, l. 64 – col. 3, l. 1. 9. See also McCann, col. 6, ll. 34-58. 14. The complex computer-controlled braking system disclosed in Ralea demonstrates that the person of ordinary skill in the art of electromechanical braking systems has a high level of skill, both in terms of education and training and in terms of the consequences associated with brake failure. PRINCIPLES OF LAW “Section 103 forbids issuance of a patent when ‘the differences between the subject matter sought to be patented and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art to which said subject matter pertains.’” KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, ___, 127 S. Ct. 1727, 1734 (2007). The question of obviousness is resolved on the basis of underlying factual determinations including (1) the scope and Appeal 2008-2432 Application 10/853,267 9 content of the prior art, (2) any differences between the claimed subject matter and the prior art, (3) the level of skill in the art, and (4) where in evidence, so-called secondary considerations. Graham v. John Deere Co., 383 U.S. 1, 17-18 (1966). See also KSR, 550 U.S. at ___, 127 S. Ct. at 1734 (“While the sequence of these questions might be reordered in any particular case, the [Graham] factors continue to define the inquiry that controls.”) ANALYSIS Claims 1 and 10-12 The Appellants argue claims 1 and 10-12 as a first group. Br. 13-24. We select claim 1 as representative, and claims 10-12 stand or fall with claim 1. 37 C.F.R. § 41.37(c)(1)(vii) (2008). The Appellants admit that Ralea discloses an electronic braking system for an aircraft (Br. 15) having a servo motor 50 that drives a ram 35 against a stack of disks 80 (Br. 16), and that movement of the ram (or pusher) 35 is advanced and returned by operation of the motor 50, 150 (Br. 17). Ralea further discloses an electromechanical aircraft brake comprising a stack of disks and a ring (housing 147) carrying a plurality of electromechanical actuators 127 each fitted with a pusher (ram 135) that is movable in register with the stack of disks under drive from an associated electric motor 150 so that rotation of the motor in a first direction causes the pusher to be pressed against the stack of disks, and causing at least one motor to rotate in a second direction opposite to the first direction so as to cause the corresponding pusher to reverse. (Facts 3 & 4). Appeal 2008-2432 Application 10/853,267 10 As such, Ralea discloses all of the elements of the electromechanical aircraft brake and method recited in claim 1, except that it does not explicitly disclose that the motor causes the corresponding pusher to reverse “beyond a distance corresponding to normal operating clearance between the pusher and the stack of disks” (Fact 10). Ralea does, however, disclose that the stack of disks will wear down during use (Facts 5-7), and it was known in the art that worn disks are replaced by a new disk stack (Fact 11). McCann discloses using the same electric motor in a brake to advance a brake-applying piston so as to adjust the running clearance as the brake linings wear during use and to retract the brake-applying piston when the brake linings need to be replaced (Facts 12 & 13). It would have been obvious to use the motor of Ralea to reverse the corresponding pusher beyond a normal operating clearing distance when the brake disk stack needs to be replaced, based on the suggestion in McCann to use the motor for replacement of braking system components. Ralea already teaches using the motor to advance and retract the pusher (Facts 3 & 4), and it was known in the art to replace the brake disk stack once the current stack is worn (Fact 11). Ralea also teaches to advance the pusher during wear of the brake disk stack in order to maintain a predetermined running clearance between the pusher and the disk stack (Facts 8 & 9). Thus, at the point in time when the disk stack is ready to be replaced, the pusher would be advanced forwardly from its starting position well beyond a distance corresponding to a normal operating clearance amount (Compare Facts 1 & 2). In order to replace the worn brake disk stack with a new thicker brake Appeal 2008-2432 Application 10/853,267 11 disk stack, the pusher must be retracted from its fully advanced position to its starting position accommodate the new, thicker brake disk stack. It would have been obvious for one having ordinary skill in the art, in view of the suggestion of McCann to use the same motor to advance the pusher for running clearance and retract the pusher for replacement of a braking system component, to use the motor of Ralea to retract the pusher all the way back to a starting position to extract the worn disk stack and to insert and accommodate the new, thicker brake disk stack. By doing so, the motor would retract the pusher through a distance which is beyond a distance corresponding to normal operating clearance between the pusher and the stack of disks. The Appellants argue that “[t]here is no basis for one skilled in the art to look to the caliper-type brake in McCann et al for teachings relevant to aircraft braking mechanisms.” Br. 15. Both McCann and Ralea disclose braking systems that use an electric motor to maintain a predetermined running clearance between a brake-applying member and a brake disk (Facts 9 & 13). As such, the teachings of McCann would have been of interest and are directly relevant to the braking system and controller routines disclosed in Ralea. Further, the level of skill in the art of electromechanical brake systems is high (Fact 14), and one having ordinary skill in the art would have been capable of applying the teachings of a caliper-type braking system, such as described in McCann, to a stacked-disk type braking system, such as is disclosed in Ralea and in the Appellants’ Specification. KSR, 550 U.S. at ___, 127 S. Ct. at 1740 (“[I]f a technique has been used to improve Appeal 2008-2432 Application 10/853,267 12 one device, and a person of ordinary skill in the art would recognize that it would improve similar devices in the same way, using the technique is obvious unless its actual application is beyond his or her skill.”). The Appellants argue that the prior art does not realize the advantages of the method of claim 1. Br. 21-22. First, we disagree with the Appellants’ contention. For example, although McCann is directed to only a single brake disk, it does disclose a method for reversing the brake-applying member to permit easy replacement of the worn disk and brake linings (Fact 13). Further, Ralea discloses routines for measuring brake disk stack wear and for maintaining a normal running clearance (Facts 5-9). Second, obviousness is not determined only by looking to the problem(s) the Appellants were trying to solve. KSR, 550 U.S. at ___, 127 S. Ct. at 1742 (“Under the correct analysis, any need or problem known in the field of endeavor at the time of invention and addressed by the patent can provide a reason for combining the elements in the manner claimed.”). The Appellants further argue that the different structures of Ralea and McCann are “incompatible due to their different operational structures.” Br. 22-24. For the reasons discussed supra, one having ordinary skill in the art would have been capable of applying the teachings of a caliper-type braking system, such as described in McCann, to a stacked-disk type braking system, such as is disclosed in Ralea. Further, the Examiner’s proposed combination of teachings from the art does not require the tappet member of McCann to be bodily incorporated into the braking system of Ralea. “The test for obviousness is not whether the features of a secondary reference may be Appeal 2008-2432 Application 10/853,267 13 bodily incorporated into the structure of the primary reference.... Rather, the test is what the combined teachings of those references would have suggested to those of ordinary skill in the art.” In re Keller, 642 F.2d 413, 425 (CCPA 1981). See also In re Sneed, 710 F.2d 1544, 1550 (Fed. Cir. 1983) (“[I]t is not necessary that the inventions of the references be physically combinable to render obvious the invention under review.”); and In re Nievelt, 482 F.2d 965, 968 (CCPA 1973) (“Combining the teachings of references does not involve an ability to combine their specific structures.”). Rather, “if a technique has been used to improve one device, and a person of ordinary skill in the art would recognize that it would improve similar devices in the same way, using the technique is obvious unless its actual application is beyond his or her skill.” KSR, 550 U.S. at ___, 127 S.Ct. at 1740. As such, the Appellants have failed to show that the Examiner erred in determining that the method of claim 1 would have been obvious to one having ordinary skill in the art at the time of the invention based on the combined teachings of Ralea and McCann. Claims 2-4 The Appellants argue claims 2-4 as a second group. Br. 24-25. We select claim 2 as representative, and claims 3 and 4 stand or fall with claim 2. 37 C.F.R. § 41.37(c)(1)(vii). Claim 2 depends from claim 1 and further recites that “the pusher is reversed sufficiently to enable a stack of new disks to be put into place, replacing a stack of worn disks.” Appeal 2008-2432 Application 10/853,267 14 The Appellants argue that neither Ralea nor McCann teach or suggest retracting a pusher in a stacked disk-type brake to permit replacement of worn disks. Br. 24-25. This argument fails to demonstrate error in the Examiner’s conclusion of obviousness based on the combined teachings of Ralea and McCann, because Ralea discloses retraction of a pusher in a stacked disk-type brake, and McCann is relied on for its suggestion to use an electric motor to retract a brake-applying member in order to replace worn brake components. One cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Merck & Co., 800 F.2d 1091 (Fed. Cir. 1986); In re Keller, 642 F.2d 413 (CCPA 1981). Claims 5-9 The Appellants argue claims 5-9 as a third group. Br. 25. We select claim 5 as representative, and claims 6-9 stand or fall with claim 5. 37 C.F.R. § 41.37(c)(1)(vii). Claim 5 recites the method of claim 1 “wherein the pusher is reversed to a reference position that is independent of the thickness of the stack of disks.” Again, the Appellants argue the references individually, contending that neither reference teaches or suggests reversal of the pusher to a position that is independent of the thickness of the stack of disks. Br. 25. This argument, however, fails to show error in the Examiner’s conclusion of obviousness based on the combined teachings of the prior art. Further, Ralea teaches moving a ram to a reference point, albeit a reference point Appeal 2008-2432 Application 10/853,267 15 based on a reference brake disk stack height that relates to the thickness of a new brake disk stack (Fact 6). This disclosure of a reference point for displacement of the ram would have suggested to one having ordinary skill in the art that the controller of Ralea could be programmed to advance or retract the ram to any desired reference point based on the particular operation being performed on the braking system. In the case of the braking method disclosed in Ralea, as modified by the teaching of McCann, it would have been obvious to retract the ram to a predetermined reference position during replacement of a worn brake disk stack so as to ensure that the ram is completely retracted for ease of removal of the worn brake disk stack and insertion of a new brake disk stack. As such, the Appellants have failed to demonstrate error in the Examiner’s conclusion of obviousness of the subject matter of claim 5 based on Ralea and McCann. CONCLUSIONS The Appellants have failed to show that the Examiner erred in determining that the method of claims 1-12 would have been obvious to one having ordinary skill in the art at the time of the invention based on the combined teachings of Ralea and McCann DECISION The decision of the Examiner to reject claims 1-12 is AFFIRMED. Appeal 2008-2432 Application 10/853,267 16 No time period for taking any subsequent action in connection with this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R. § 1.136(a)(1)(iv) (2007). AFFIRMED vsh SUGHRUE MION, PLLC 2100 PENNSYLVANIA AVENUE, N.W. SUITE 800 WASHINGTON DC 20037 Copy with citationCopy as parenthetical citation