Ex Parte Humphrey et alDownload PDFPatent Trial and Appeal BoardNov 27, 201712725051 (P.T.A.B. Nov. 27, 2017) Copy Citation United States Patent and Trademark Office UNITED STATES DEPARTMENT OF COMMERCE United States Patent and Trademark Office Address: COMMISSIONER FOR PATENTS P.O.Box 1450 Alexandria, Virginia 22313-1450 www.uspto.gov APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO. 12/725,051 03/16/2010 DANIEL HUMPHREY 82262099 8480 56436 7590 11/29/2017 Hewlett Packard Enterprise 3404 E. Harmony Road Mail Stop 79 Fort Collins, CO 80528 EXAMINER AMRANY, ADI ART UNIT PAPER NUMBER 2836 NOTIFICATION DATE DELIVERY MODE 11/29/2017 ELECTRONIC Please find below and/or attached an Office communication concerning this application or proceeding. The time period for reply, if any, is set in the attached communication. Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the following e-mail address(es): hpe.ip.mail@hpe.com chris. mania @ hpe. com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte DANIEL HUMPHREY,1 Mohamed Amin Bemat, Reynaldo P. Domingo, and Reginald A. Whyte Jr. Appeal 2016-006681 Application 12/725,051 Technology Center 2800 Before LINDA M. GAUDETTE, MARKNAGUMO, and AVELYN M. ROSS, Administrative Patent Judges. NAGUMO, Administrative Patent Judge. DECISION ON APPEAL Daniel Humphrey, Mohamed Amin Bemat, Reynaldo P. Domingo, and Reginald A. Whyte Jr. (“Humphrey”) timely appeal under 35 U.S.C. § 134(a) from the Final Rejection2 of all pending claims 16-26. We have jurisdiction. 35 U.S.C. § 6. We reverse. 1 The real party in interest is identified as Hewlett-Packard Development Company, LP. (Appeal Brief, filed 15 April 2015 (“Br.”), 2.) 2 Office action mailed 10 December 2014 (“Final Rejection”; cited as “FR”). Appeal 2016-006681 Application 12/725,051 OPINION A. Introduction3 The subject matter on appeal relates to a fan control “system” (independent claim 23) and a generally corresponding method (independent claim 16) for controlling pulse-width modulated (“PWM”) DC fans. (Spec. 1 [0009] and 2 [[0012].) According to the '051 Specification, PWM fans are “well known . . . and are generally considered to be more energy efficient when compared to linear regulating (voltage control) fan motors.” (Spec. 2 [0012].) Such fans are said to be used to cool various temperature- sensitive computer components, {id. at 1 [0002].) The speed of a PWM fan depends on the duty cycle (roughly, the “on- time”; cf. Chiu4, col. 3,11. 61-64) of the PWM control signal applied to the fan. However, as indicated by the lowest trace in Figure 2, shown on the following page, for a given DC voltage, only a certain range of motor speeds (revolutions per minute, “RPM”) can be obtained. In this case, at 6 volts, the maximum RPM obtainable is a little less than 7000 RPM. (Spec. 3 [0017].) To obtain a higher motor speed, e.g., 7200 RPM, a higher voltage, e.g., 8, 10, or 12 V, must be selected. As shown in Figure 2, however, increasing the voltage at a given RPM (i.e., a given duty cycle) only increases the power needed to run the motor. Thus, it is most 3 Application 12/725,051, Fan control system and method, filed 16 March 2010. We refer to the “'051 Specification,” which we cite as “Spec.” 4 Full cite infra at 5 n.7. 2 Appeal 2016-006681 Application 12/725,051 economical to use the lowest available voltage, which also generates the least heat, to run the motor. {Specification Figure 2 is shown below (annotations added)} {Fig. 2 shows power versus fan speed for a plurality of DC supply voltages} In the words of the Specification, “[b]y dynamically adjusting the DC voltage that is supplied to the PWM fans, the power efficiency of the associated PWM circuitry can be kept high over a variety of fan speeds.” {Id. at 3—4 [0017].) According to the Specification, “it has been determined in laboratory tests that power efficiency increases of up to 40% may be achieved by implementing a fan control system based on the teachings contained herein.” {Id. at 4 [0017].) 3 Appeal 2016-006681 Application 12/725,051 Claim 16 is representative and reads: A process comprising: a) determining a desired second fan speed for a pulse- width modulated (PWM) fan being operated at first fan speed using a first minimum available voltage and a first duty cycle of a PWM control signal; b) determining, based on the desired second fan speed, a second minimum available voltage from a set of plural discrete available voltages, the second minimum available voltage being different from said first minimum available voltage, the second minimum available voltage being the minimum of the available voltages capable of providing the desired second fan speed for the PWM fan; c) determining, based on the desired second fan speed and the determined second minimum available voltage, a second duty cycle that, when used to drive the PWM fan using the determined second minimum available voltage, will achieve the desired second fan speed for the PWM fan; and d) changing from operating the PWM fan at the first fan speed to operating the PWM fan at the second fan speed by simultaneously adjusting a voltage control signal and the PWM control signal to change from the first minimum available voltage to the second minimum available voltage and from the first duty cycle to the second duty cycle. (Claims App., Br. 14; some indentation, paragraphing, and emphasis added.) Independent claim 23 is drawn to a “system” similar to claim 16, but claim 23 does not require expressly that the second minimum available voltage be different from the first minimum available voltage. 4 Appeal 2016-006681 Application 12/725,051 Both independent claims 16 and 23 require that the voltage control signal and the PWM control signal be adjusted simultaneously. The Examiner maintains the following grounds of rejection5’6: A. Claims 16-26 stand rejected under 35 U.S.C. § 103(a) in view of the combined teachings of Chiu7 and Dishman.8 B. Claims 16-26 stand rejected under 35 U.S.C. § 103(a) in view of the combined teachings of Chiu and Alon.9 B. Discussion The Board’s findings of fact throughout this Opinion are supported by a preponderance of the evidence of record. Humphrey urges the Examiner erred in finding that Chiu and either of the secondary references, alone or in combination, teach varying both the PWM signal and the voltage control signal simultaneously, as required by the independent claims. (Br. 8-9 (Rejection A); 11-12 (Rejection B).) The Examiner finds that “Chiu discloses that the fan speed [Sf] can be controlled both above and below Sref.” (FR4,11. 15-16.) On this basis, the 5 Examiner’s Answer mailed 9 July 2015 (“Ans.”). 6 Because this application was filed before the 16 March 2013, effective date of the America Invents Act, we refer to the pre-AIA version of the statute. 7 Chung-Lung Chiu et al, Fan speed control device and method detailed description of the invention, U.S. Patent No. 7,447,423 B2 (2008). 8 C. Charles Dishman et al., Apparatus, system, and method for improved fan control in a power supply, U.S. Patent No. 8,158,160 B2 (17 April 2012), based on an application filed 30 December 2008. 9 Moshe Alon et al., Fan speed change control, U.S. Patent Application Publication 2007/0297893 Al (2007). 5 Appeal 2016-006681 Application 12/725,051 Examiner interprets Chiu “as including a fan speed change from speed 1 (above Sref) to speed2 (below Sref).” (Id. at 11. 15-17.) The Examiner finds further that Chiu describes two modes of controlling the fan speed. The first mode, when the fan speed Sf is greater than a reference speed Sref, involves leaving the voltage fixed and varying only the PWM signal. (Id. at 11. 17- 19.) The second mode, when the fan speed Sf is less than the reference speed Sref, involves setting the PWM signal to a predetermined minimum value, and varying the voltage. (Id. at 11. 19-21.) In the Examiner’s words, “[a]s can be seen, the Chiu processor changes from high fan speed to low fan speed by adjusting both PWM and voltage.” (Id. at 11. 21-22.) The Examiner finds further that “Chiu also does not expressly disclose the PWM/voltage control signals are adjusted ‘simultaneously.’” (Id. at 5, 11. 16-17.) The Examiner also finds that Chiu does not “expressly disclose” determining a desired second fan speed, or the second PWM signal and second voltage that would produce the second fan speed. (Id. at 11. 10-16.) The Examiner finds that Dishman discloses a system that provides these findings. (FR 5,11. 18, to 6,1. 10.) More particularly, the Examiner finds that Dishman describes limitation b), determining a second voltage [for a second fan speed] different from the first voltage [for the first fan speed]. (FR 6, citing Dishman, col. 10,11. 20—28.) The Examiner also finds that Dishman discloses limitation c), “determining, based on the desired second fan speed, a second duty cycle that will achieve the desired second fan speed.” (Id. at 11. 4-5, citing Dishman, col. 10,11. 13-19.) The Examiner finds that “Dishman does not expressly disclose manipulating both values 6 Appeal 2016-006681 Application 12/725,051 together” (id. at 11. 10-11), but reasons that “this teaching is found in Chiu (and is not required to be found in Dishman)” (id. at 1. 11). We find in the passages of Chiu cited by the Examiner10 no substantial evidence indicating that Chiu discloses or suggests the simultaneous adjustment of both the voltage control signal and the PWM control signal. Rather, Chiu describes a sequential adjustment, first of the PWM control signal to a minimum value (Chiu col. 4,11. 6-18), and then, if necessary (“to further decrease the rotation speed of the fan”; Chiu, col. 4,11. 18-19), decreasing the voltage. Even in the procedure in which an operator of Chiu’s system changes the speed from below Sref to above Sref (or vice- versa), it is not clear that substantial evidence, let alone a preponderance of the evidence, supports the Examiner’s conclusion that the simultaneous 10 The Examiner mentions Chiu Figure 5 (FR 3,1. 23), but does not cite Chiu column 5, lines 25^48, especially lines 46 48), discussing an embodiment in which the switch (PWM) signal S1 and the voltage regulator signal S2 can be in parallel. Whether such an embodiment could form the basis of a reasonable rejection of the presently claimed subject matter would require extensive fact finding and analysis that we decline to undertake in the first instance, as our primary role is review, not examination de novo. In this regard, in the event of further examination, we recommend further consideration of whether claim 23 requires, implicitly, that the second minimum available voltage be different from the first minimum available voltage. In this regard, we note that the term “change” (and its variants) in part d) would have its ordinary meaning, absent evidence in the Specification that a broader meaning including “zero change” as well as “non-zero change” is intended. (Cf. Alon 3 [0031]: “The term change as used herein should be construed to include zero and/or non-zero change, as appropriate.”). We emphasize that we neither make nor imply any findings in this regard. 7 Appeal 2016-006681 Application 12/725,051 adjustment of the voltage control signal and the PWM control signal would have been obvious within the meaning of § 103. Moreover, the parameters in lookup table 320 described by Dishman at column 9, lines 35-53, in particular, the power dissipation values associated with “fan speed parameters that determine the fan speed such as a pulse-width, voltage, or resistance” (Dishman, col. 8,11. 39—41) are parameters of a PWM fan {id. at col. 9,1. 66, to col. 10,1. 19), a voltage regulated-fan {id. at col. 10,11. 20-28), and a rheostat fan {id. at 11. 29-34), respectively. Thus, the Examiner’s findings regarding Dishman do not relate to a single PWM fan, but to a PWM fan, and, in an alternative embodiment described by Dishman, to a voltage-regulated fan. A similar problem exists with Alon. Thus, the Examiner’s finding b) (determination of a second voltage appropriate for the desired second fan speed, the second voltage being different from the first voltage) based on Alon paragraph [0041] (FR 9,11. 6-9) and the Examiner’s finding c) (determining a second duty cycle for the second fan speed) based on Alon, paragraph [0040] (FR 9,11. 9-10), are based on disclosure relating to two different types of fan, namely a PWM fan (paragraph [0040]) and a voltage- (or current-) regulated fan (paragraph [0041]). In conclusion, the Examiner’s findings regarding Dishman and Alon are not supported by substantial evidence, and a proper basis for the combination of their teachings with those of Chiu has not been established. Critical and harmful errors of fact-finding regarding each of the applied references undermine the appealed rejection. We therefore reverse. 8 Appeal 2016-006681 Application 12/725,051 C. Order It is ORDERED that the rejection of claims 16-26 is reversed. REVERSED 9 Copy with citationCopy as parenthetical citation