DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 6/27/24 has been considered by the examiner.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claim(s) 1-3 and 18-20 are rejected under 35 U.S.C. 103 as being unpatentable over Escudero (US 2021/0376741) in view of Lai (US 2014/0177281).
With respect to claim 1, Escudero discloses a phase shift full bridge (PSFB) converter, comprising: a transformer (Fig. 1 T) having a primary side and a secondary side; a full-bridge comprising a first pair of switch devices (Fig. 1 QA,QB) connected in series at a first node (Fig. 1A) coupled to a first terminal (Fig. 1 IN) of the primary side, and a second pair of switch devices (Fig. 1 QC,QD) connected in series at a second node (Fig. 1 B) coupled to a second terminal (Fig. 1 GND1) of the primary side; a pair of diode devices (Fig. 1 D1,D2) connected in series at a third node (Fig. 1 C) coupled to the first terminal of the primary side; an inductor (Fig. 1 Lr) coupled between the first node and the third node; a rectifier (Fig. 1 QEH,QEL,QFH,QFL) coupled to the secondary side. Escudero does not detail the primary side controller.
Lai discloses a phase shift full bridge converter having a controller (Fig. 3 52), wherein in a first mode (Fig. 4 Modulation mode selector 0), the controller is configured to operate the second pair of switch devices as a leading power transfer leg and the first pair of switch devices as a lagging power transfer leg each power transfer cycle (Fig. 5), wherein in a second mode (Fig. 4 Modulation mode selector 1), the controller is configured to operate the first pair of switch devices as the leading power transfer leg and the second pair of switch devices as the lagging power transfer leg each power transfer cycle (Fig. 2), wherein the controller is configured to seamlessly transition (Fig. 4 Controlling signal seamless in normal operation) between the first and second modes without interruption of the PSFB converter. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to implement a controller, wherein in a first mode, the controller is configured to operate the second pair of switch devices as a leading power transfer leg and the first pair of switch devices as a lagging power transfer leg each power transfer cycle, wherein in a second mode, the controller is configured to operate the first pair of switch devices as the leading power transfer leg and the second pair of switch devices as the lagging power transfer leg each power transfer cycle, wherein the controller is configured to seamlessly transition between the first and second modes without interruption of the PSFB converter, in order to evenly distribute the heat between the switching legs and prevent the first switching leg from overheating.
With respect to claim 2, Escudero in view of Lai make obvious the PSFB converter of claim 1, wherein an indicator (Fig. 9A V3) that indicates when the controller is to transition from one mode to the other mode is adjustable (Fig. 9A RTD1,RTD2).
With respect to claim 3, Escudero in view of Lai make obvious the PSFB converter of claim 2, wherein the controller is configured to adjust the indicator based on efficiency data (the switch devices have lower efficiency at higher temperatures and Fig. 9A RTD1,RTD2 indicate the temperature in order to lower the temperature to increase the efficiency of the switch devices) collected during use of the PSFB converter.
With respect to claim 18, Escudero in view of Lai make obvious the PSFB converter of claim 1, wherein in the first mode, the second pair of switch devices energizes (Lai Fig. 5 first DTs of cycle) the inductor during a first part (Lai Fig. 5 Q3,Q2 ON) of each power transfer cycle (Lai Fig. 5 Ts) and the first pair of switch devices energizes (Lai Fig. 5 second DTs of cycle) the inductor during a second part (Lai Fig. 5 Q1,Q4 ON) of each power transfer cycle that follows the first part, and wherein in the second mode, the first pair of switch devices energizes (Lai Fig. 2 first DTs of cycle) the inductor during the first part (Lai Fig. 2 Q1,Q4 ON) of each power transfer cycle (Lai Fig. 2 Ts) and the second pair of switch devices energizes the inductor during the second part (Fig. 2 Q3 and Q2 ON) of each power transfer cycle.
With respect to claim 19, Escudero in view of Lai make obvious the PSFB converter of claim 1, wherein the controller is configured to operate in the first mode at heavier load conditions (since Lai Fig. 8 operates alternates under high and low conditions) and operate in the second mode at lighter load conditions (since Lai Fig. 8 operates alternates under high and low conditions).
With respect to claim 20, Escudero in view of Lai make obvious the method as set forth above. See claim 1 for additional details.
Allowable Subject Matter
Claims 4-17 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims. The following is a statement of reasons for the indication of allowable subject matter:
With respect to claim 4, the prior art does not disclose or suggest, in combination with the limitations of the base claim and any intervening claims, primarily, wherein to seamlessly transition from one mode to the other mode without interruption of the PSFB converter, the controller is configured to terminate the pair of switch devices acting as the leading power transfer leg at the end of the present power transfer cycle so that this pair of switch devices becomes the lagging power transfer leg for the next power transfer cycle, and extend the pair of switch devices acting as the lagging power transfer leg into the next power transfer cycle so that this pair of switch devices becomes the leading power transfer leg for the next power transfer cycle.
With respect to claim 5, the prior art does not disclose or suggest, in combination with the limitations of the base claim and any intervening claims, primarily, wherein to transition from the first mode to the second mode, the controller is configured to shorten a pair of PWM (pulse width modulation) pulses that control the first pair of switch devices and lengthen a pair of PWM pulses that control the second pair of switch devices at the end of the last power transfer cycle in the first mode, such that the first pair of switch devices becomes the leading power transfer leg and the second pair of switch devices becomes the lagging power transfer leg for the first power transfer cycle in the second mode.
With respect to claim 10, the prior art does not disclose or suggest, in combination with the limitations of the base claim and any intervening claims, primarily, wherein to transition from the second mode to the first mode, the controller is configured to lengthen a pair of PWM (pulse width modulation) pulses that control the first pair of switch devices and shorten a pair of PWM pulses that control the second pair of switch devices at the end of the last power transfer cycle in the second mode, such that the second pair of switch devices becomes the leading power transfer leg and the first pair of switch devices becomes the lagging power transfer leg for the first power transfer cycle in the first mode.
With respect to claim 15, the prior art does not disclose or suggest, in combination with the limitations of the base claim and any intervening claims, primarily, wherein when transitioning from one mode to the other mode, the controller is further configured to adjust for a difference in duty cycle loss between the first and second modes.
The aforementioned limitations in combination with all remaining limitations of the respective claims are believed to render the aforementioned indicated claim and any dependent claims thereof patentable over the art of record.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to HARRY RAYMOND BEHM whose telephone number is (571)272-8929. The examiner can normally be reached M-F: 8-5 EST.
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/HARRY R BEHM/Primary Examiner, Art Unit 2838