Ex Parte Rollinger et alDownload PDFBoard of Patent Appeals and InterferencesJun 18, 200911209452 (B.P.A.I. Jun. 18, 2009) Copy Citation UNITED STATES PATENT AND TRADEMARK OFFICE ____________ BEFORE THE BOARD OF PATENT APPEALS AND INTERFERENCES ____________ Ex parte JOHN E. ROLLINGER, PAUL A. PIETRZYK, MICHAEL SWEPPY, ERIC A. LUEHRSEN, and ROBERT M. GRANT ____________ Appeal 2009-001555 Application 11/209,452 Technology Center 3700 ____________ Decided:1 June 18, 2009 ____________ Before LINDA E. HORNER, JOHN C. KERINS, and STEVEN D.A. McCARTHY, 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 2009-001555 Application 11/209,452 2 STATEMENT OF THE CASE John Rollinger et al. (Appellants) seek our review under 35 U.S.C. § 134 of the Examiner’s decision rejecting claims 1-22. We have jurisdiction under 35 U.S.C. § 6(b) (2002). SUMMARY OF DECISION We REVERSE. THE INVENTION The Appellants’ claimed invention is a method for operating an engine having a variable cam timing control system, including methods for operating the engine in the event of a fault in a sensor used in the variable cam timing control system. Spec. 1:6-9. Claims 1 and 11, reproduced below, are representative of the subject matter on appeal. 1. A method for operating an engine having a variable cam timing control system, for controlling a camshaft angle in such engine, comprising: setting the camshaft angle to a constant predetermined angle for a predetermined duration after failure in a sensor used to control the variable cam timing system; and subsequently allowing the camshaft angle to return to the camshaft angle determined by the variable cam timing system. 11. A method for operating an engine, comprising: maintaining camshaft angle substantially constant for up to a predetermined duration in response to a sensor failure. Appeal 2009-001555 Application 11/209,452 3 THE EVIDENCE The Examiner relies upon the following evidence: Urushihata US 7,107,951 B2 Sep. 19, 2006 THE REJECTION The Appellants seek our review of the Examiner’s decision to reject claims 1-22 under 35 U.S.C. § 103(a) as unpatentable over Urushihata. ISSUE The Examiner found that Urushihata “is able to detect a failure in a sensor, move to a mechanical reference position, and use accumulated values of timing variations at that mechanical reference position for calculating actual valve timing (column 19, lines 1-7).” Ans. 4-5. The Examiner further found that the reference states or suggests that “the mechanical reference position is maintained until an accumulated value of valve timing variation from the mechanical reference position can be calculated and used to set the actual valve timing,” and that it would be obvious from this disclosure that the “mechanical reference position would have to be maintained for a specific duration of time.” Ans. 5. The Examiner found that the inclusion of specific time periods was “a matter of obvious choice to one of ordinary skill in the art.” Ans. 3-4. The Examiner concluded Urushihata renders obvious the subject matter of claims 1-22. Ans. 5. The Appellants contend that Urushihata does not disclose that, in response to a sensor failure, the device either sets the camshaft angle to a constant predetermined angle for a predetermined duration, or maintains the Appeal 2009-001555 Application 11/209,452 4 camshaft angle at a constant angle for a predetermined duration. App. Br. 6- 7, 10-11. In particular, the Appellants contend that Urushihata does not disclose maintaining the camshaft at a mechanical reference position; rather, Urushihata discloses a reference position from which to commence the calculations of actual valve timing. App. Br. 9. The issue before us is: Have the Appellants shown the Examiner erred in a finding of fact underlying the conclusion of obviousness that Urushihata discloses moving the camshaft to a predetermined angle and maintaining the camshaft angle at a constant angle in response to a sensor failure? FINDINGS OF FACT We find that the following enumerated facts 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). 1. Urushihata discloses 26 embodiments of a variable valve timing control device of an internal combustion engine for varying the valve timing of intake or exhaust valves. Urushihata, col. 1, ll. 17-20; passim. The Examiner’s rejection is based on the disclosure of Urushihata’s sixth embodiment. Ans. 3-4. 2. Urushihata discloses it is a shortcoming of the prior art that calculation of the actual valve timing was done on the basis of crank and camshaft angle signals (in steps), lowering precision of control because actual valve timing changes continuously rather than in steps. Urushihata, col. 16, ll. 43-65. Urushihata discloses it is an object of the sixth Appeal 2009-001555 Application 11/209,452 5 embodiment to increase precision of control by calculating actual valve timing even during intervals when the cam angle signal is not being outputted. Urushihata, col. 16, l. 66 to col. 17, l. 4. 3. In the sixth embodiment, actual valve timing is calculated at a predetermined interval (computation period, P) matching the signal output interval of the cam angle sensor and crank angle sensor. Urushihata, col. 17, ll. 50-61; col. 19, ll. 19-24. When the cam angle sensor 19 is operating properly, each time cam angle sensor 19 outputs a signal, Engine Control Unit (ECU) 30 calculates actual valve timing (VTC) based on the cam angle signal from the cam angle sensor 19 and the crank angle signal from the crank angle sensor 20. Urushihata, col. 8, ll. 9-10; col. 19, ll. 19-24. Then valve timing variation (ΔVT) is calculated based on the difference between the speed of motor 26 and the speed of the intake-side camshaft over the known computation period. Urushihata, col. 19, ll. 24-27. Final actual valve timing (VT) is then calculated using the actual valve timing (VTC) and the valve timing variation (ΔVT). Urushihata, col. 19, ll. 27-30; Figs. 15, 17 (showing actual valve timing calculation program). The ECU 30 feedback-controls the variable valve timing device 18, which varies the rotation phase of the intake-side camshaft 16 with respect to the crankshaft 12. Urushihata, col. 7, ll. 5-10; col. 19, ll. 14-18; Figs. 1, 2. 4. In the sixth embodiment, when the cam angle sensor fails, ECU 30 calculates final actual valve timing by two alternate methods. Urushihata, col. 22, ll. 27-40. 5. In the first method, final actual valve timing (VT) is calculated by adding the actual valve timing (VTC) prior to cam angle sensor failure to the valve timing variation ΔVTH (the accumulated value of dVTH) Appeal 2009-001555 Application 11/209,452 6 subsequent to the cam angle sensor failure. Urushihata, col. 22, ll. 27-31; Fig. 16. 6. In the second method, which is used for both failure of the cam angle sensor 19 and for engine stoppage, final actual valve timing (VT) can be calculated by an accumulated value of valve timing variation from a reference position (either a mechanical reference position, such as a most retarded angle position, or a reference position detected by other means). Urushihata, col. 22, ll. 35-40; col. 19, ll. 2-7; Fig. 17. 7. In both calculation methods (Facts 5, 6), valve timing variation (dVTH) is calculated and accumulated based on the speed difference between the motor 26 and the intake-side camshaft 16 over the known computation period. Urushihata, col. 20, l. 44 to col. 21, l. 30; Figs. 16, 17. 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, 406 (2007). The question of obviousness is resolved on the basis of underlying factual determinations including (1) the scope and 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 407 (“While the sequence of these questions might be reordered in any particular case, the [Graham] factors continue to define the inquiry that controls.”) Appeal 2009-001555 Application 11/209,452 7 ANALYSIS Rejection of claims 1-22 under 35 U.S.C. § 103(a) as unpatentable over Urushihata Claims 1-10 Claim 1 contains the limitation of “setting the camshaft angle to a constant predetermined angle for a predetermined duration after failure in a sensor used to control the variable cam timing system.” The Examiner’s rejection finds that column 19, lines 1 through 7 of Urushihata (the sixth embodiment) discloses that when the cam angle sensor fails, “the actual valve timing can be calculated by going to a mechanical reference position (for example, a most retarded position).” Ans. 4. We find that Urushihata does not operate in this manner. Urushihata discloses a variable valve timing control device for internal combustion engines (Fact 1). It is an object of the sixth embodiment of the device to increase precision by calculating actual valve timing even during intervals when the cam angle signal is not being outputted, as compared to the prior art which performs updates in steps based on the interval of the crank and camshaft angle signals (Fact 2). While the cam angle sensor is operational, the Engine Control Unit calculates final actual valve timing using actual valve timing (based on the cam angle signal and the crank angle signal) and the valve timing variation (the difference between the motor speed and the camshaft speed) (Fact 3). When the cam sensor fails, the device responds by calculating final actual valve timing by two alternate methods (Fact 4). The first method calculates final actual valve timing by adding an accumulated value of valve timing variation subsequent to the cam sensor failure to the last outputted Appeal 2009-001555 Application 11/209,452 8 actual valve timing (Fact 5). The second method calculates final actual valve timing by an accumulated value of valve timing variation from a reference position (Fact 6). Each of these methods includes valve timing variation in the calculation, which is based on the speed difference between the intake-side cam shaft and the motor over the computation period subsequent to the sensor failure (Fact 7). From this operation, we conclude that in response to a sensor failure, Urushihata does not use a “constant predetermined angle,” but rather sets the camshaft angle to a calculated angle based in part on valve timing variation which is a calculation performed subsequent to cam angle sensor failure. This operation also makes clear that the Examiner based the conclusion of obviousness upon an erroneous underlying finding of fact that Urushihata discloses that after cam angle sensor failure, the camshaft angle moves to a reference position. Rather, Urushihata discloses the reference position is used as a location to measure from, not a position to move to (Fact 6). The Appellants have shown the Examiner erred in concluding the subject matter of claim 1 was obvious in view of Urushihata because the Examiner erred in the underlying finding that Urushihata discloses setting the camshaft angle to a constant predetermined angle after failure in a sensor. We also reverse the Examiner’s decision to reject claims 2-10 by virtue of their dependence on claim 1. Claim 11 The Appellants argue that Urushihata does not disclose the limitation of claim 11 of “maintaining camshaft angle substantially constant for up to a predetermined duration in response to a sensor failure” because Urushihata uses “closed loop control whereas with the present invention, a Appeal 2009-001555 Application 11/209,452 9 predetermined angle is commanded as open loop actuator command without feedback.” App. Br. 10-11. We agree with the Appellants’ argument based on the operation of Urushihata’s device explained in the analysis of claim 1, supra. Urushihata’s device calculates final actual valve timing when the cam angle sensor is inoperative based in part on the feedback of valve timing variation subsequent to cam angle sensor failure (a closed loop) (Facts 4-6), while the claimed device has the predetermined response of maintaining the camshaft angle substantially constant (open loop). Further, as we found in the analysis of claim 1, supra, Urushihata does not disclose that after cam angle sensor failure the camshaft angle moves to and thereafter maintains the camshaft angle at a constant reference position, as found by the Examiner. Ans. 5. The Appellants have shown the Examiner erred in the decision to reject claim 11. We also reverse the decision to reject claims 12-19 by virtue of their dependence on claim 11. Claims 20 and 21 Similarly to claim 11, claims 20 and 21 contain the limitations that in response to detection of a sensor failure, either the device drives the camshaft to a constant position (claim 20), or the device maintains the camshaft at a constant angle (claim 21). In the analysis of claim 1, supra, we determined that after failure of the cam angle sensor, Urushihata sets the camshaft angle based on one of two calculations (Fact 4). Urushihata does not drive the camshaft to a constant position, nor maintain the camshaft at a constant angle. The Appellants have shown the Examiner erred in the decision to reject claims 20 and 21. Appeal 2009-001555 Application 11/209,452 10 Claim 22 Claim 22 contains the limitation of having “code for setting the camshaft angle to a constant predetermined angle for a predetermined duration after failure in a sensor used to control the variable cam timing system.” We determined in the analysis of claim 1, supra, that the subject matter of claim 1 was not obvious in view of Urushihata because the Examiner erred in finding that Urushihata discloses setting the camshaft angle to a constant predetermined angle after failure in a sensor. Because Urushihata does not disclose a device that takes this action, Urusihata also does not disclose code for taking such action. The Appellants have shown the Examiner erred in the decision to reject claim 22. CONCLUSION The Appellant has shown the Examiner erred in a finding of fact underlying the conclusion of obviousness because Urushihata does not, in response to a sensor failure, set the camshaft angle to a constant predetermined angle or maintain the camshaft angle at a constant angle. DECISION We reverse the Examiner's rejection of claims 1-22. REVERSED Vsh RICHARD M. SHARKANSKY PO BOX 557 MASHPEE MA 02649 Copy with citationCopy as parenthetical citation