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 .
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1 and 2 are rejected under 35 U.S.C. 103 as being unpatentable over Kagan (US20080238386) in view of Heo (KR20150108133A) and further in view of Morris (US5073849A) with citations made to attached machine translations.
PNG
media_image1.png
300
558
media_image1.png
Greyscale
Fig. 7 of Kagan
Regarding claim 1, Kagan teaches a heating device, comprising:
a resonant circuit (10) comprising:
an inverter circuit (14) configured to provide a resonant tank current and a resonant tank voltage; and
a resonant tank comprising a heating coil (coil) , a resonant tank capacitor (22), a resonant tank equivalent inductor (26) and a resonant tank equivalent impedance (28);
a detection unit (15) electrically coupled with the resonant circuit (10), wherein after a switch (30) of the inverter circuit ([0056] 14, 16, 18, 20, 30) is switched from a conducting state to a non-conducting state (Fig. 1 [0045-0046] switches 20 and 30 are closed, then switch 30 ) such that the resonant tank voltage becomes zero when switch is opened ([0046] switches 20 and 30 are closed, then switch 30 opened directing current to capacitor 22 without being delivered to the load, where resonant tank voltage would be zero), the resonant tank (Coil, 22, 26 28) operates in a discharge waveform (Fig. 7, VL, IL discharge voltage and current from capacitor 22),
wherein the detection unit (15) detects the resonant tank current (IL) and the resonant tank voltage (VL) during the discharge waveform (Fig. 7 [0054-0085] where detections are based off of discharged voltage or current from capacitor 22) to acquire a reference current value (71), a first zero-crossing time point (72), a second zero-crossing time point (73), a time difference (tlag), a resonant period (tcross) and
wherein the reference current value (71) is a current value of the resonant tank current (IL) when the resonant tank voltage (VL) is zero (75, Fig. 7),
the time difference (tlag) is a time length between a time point when the resonant tank voltage is zero (75) and the first zero-crossing time point (72, where tlag is the same between current point 70 and voltage point 75, and between current point 72 and voltage point75),
and the resonant period (tcross) is defined according to the first zero-crossing time point (72) and the second zero-crossing time point (73);
wherein the first zero-crossing time point (72) is a first time point corresponding to a first zero value of the resonant tank current after the resonant tank voltage is zero (75), and the second zero-crossing time point (73) is a second time point corresponding to a second zero value of the resonant tank current after the resonant tank voltage is zero (75), and
a control unit (15) configured to control the inverter circuit (14) to output the resonant tank current (IL) and the resonant tank voltage (VL), so that a heating power of the heating coil is adjustable ([0055, 0165] the skilled person can control the shape of the individual current pulses and the on/off timing of the current pulses in order to deliver a desired current signal to a heating element)
wherein the detection unit (15) calculates an inductance of the resonant tank equivalent inductor (LL) according to a capacitance of the resonant tank capacitor (C), the resonant period (fL) and a first expression (2.1),
the detection unit (15) calculates an impedance value of the resonant tank equivalent impedance (Rch) according to the inductance of the resonant tank equivalent inductor (Lch), the time difference (tmax), the resonant period (tcross), the reference current value (IL), and a second expression, and the control unit controls the heating power of the heating coil (Ich) according to the inductance of the resonant tank equivalent inductor (Lch) and the impedance value of the resonant tank equivalent impedance (Rch),
wherein Leq is the inductance of the resonant tank equivalent inductor (LL), Cr is the capacitance of the resonant tank capacitor (C), and T is the resonant period (tcross) and the first expression is expressed as a following mathematic formula ([0065-0066] equations 2.0 and 2.1, in combination are the equivalent the following formula):
L
e
q
=
τ
2
π
C
r
2
wherein Req is the impedance value of the resonant tank equivalent impedance (RCH), I0 is the reference current value, Δt is the time difference, and IN is the negative peak value of the resonant tank current, and the second expression is expressed (equation 6.5) as a mathematic formula.
Kagan is silent on the resonant tank operates in a discharge waveform in a negative half cycle, a negative peak current value and a mathematic formula
PNG
media_image2.png
84
220
media_image2.png
Greyscale
Heo teaches a negative peak current value (1).
Kagan and Heo are considered to be analogous to the claimed invention because they are in the same field of detection circuitry. It would have been obvious to have modified Kagan to incorporate the teachings of Heo to determine a negative peak current value as using negative peak current values simplifies digital calculation operations and use of blocks noise in further calculations (Heo [0009]).
Kagan discloses the invention essentially as claimed as discussed above and further discloses a resonant resistance of the circuit (Rch) being the value defined in by the equation 6.5 in [0089]. Kagan does not expressly disclose determining the resonant resistance of the circuit, being the equivalent of the impedance value of the resonant tank, by the equation of the applicant's claim 1. Kagan discloses that the resonant resistance of the circuit needs to be optimized such that current applied to the circuit may remain in a desirable range, not exceeding a maximum limit of switches in use of the circuit as it is switches in particular have limitations that should not be exceeded ([0080, 0095]). As seen in [0080-0095], the resonant resistant Rch, is defined by equation 6.5, based on variables such as inductances, current values, and time differences such that the resonant resistance of the circuit is disclosed to be a result effective variable in that changing the resonant resistance affects the optimal operation of the current of the circuit and the switches in the circuit. Therefore, it would have been obvious to one having ordinary skill in the art at the time of the invention to modify the device of Kagan by making the resonant resistance of the circuit be the value found by the equation of the applicant's claim 1, as a matter of routine optimization since it has been held that “where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955)(MPEP 2144.05).
Kagan and Heo are silent on teach the resonant tank operates in a discharge waveform in a negative half cycle.
Morris teaches the resonant tank operates in a discharge waveform (tank voltage) in a negative half cycle (Fig. 4A-4D).
Kagan, Heo, and Morris are considered to be analogous to the claimed invention because they are in the same field of detection circuitry. It would have been obvious to have modified Kagan and Heo to incorporate the teachings of Morris to have the resonant tank operate a discharge waveform in a negative half cycle, as to be able to the related switches in response to voltages that are proportional to the magnitudes of loads placed (Morris Col. 4 lines 10-15).
Regarding claim 2, Kagan, Heo, and Morris teach the heating device according to claim 1, and Kagan teaches wherein the detection unit (15) comprises a parameter acquisition unit ([0015] monitoring circuit), and the parameter acquisition unit is electrically coupled with the resonant tank to detect the resonant tank current and the resonant tank voltage ([0015]),
wherein when the resonant tank voltage is zero (Fig. 7 VL at 0V), the parameter acquisition unit acquires the resonant period and the negative peak current value of the resonant tank current according to the resonant tank current and the resonant tank voltage ([0109] Fig. 7 tcross determined and current IL having a negative peak shown in Fig. 7 at a zero cross of VL).
Claims 3 and 5 are rejected under 35 U.S.C. 103 as being unpatentable over Kagan (US20080238386), Heo (KR20150108133A), and Morris (US5073849A) as applied to claim 1 above, and further in view of Bassill (US20030192881).
Regarding claim 3, Kagan, Heo, and Morris teach the heating device according to claim 2, and Kagan teaches wherein the parameter acquisition unit comprises: a zero-crossing detection circuit (15) electrically coupled with the resonant tank ([0015] monitoring circuit),wherein the zero-crossing detection circuit detects the resonant tank current and the resonant tank voltage ([0015]), and the zero-crossing detection circuit acquires the resonant period according to the resonant tank current and the resonant voltage ([0065] tcross); but is silent on a negative peak value detection circuit electrically coupled with the resonant tank , wherein the negative peak value detection circuit detects the resonant tank current and the resonant voltage, and the negative peak value detection circuit acquires the negative peak current value according to the resonant tank current and the resonant tank voltage.
PNG
media_image3.png
306
608
media_image3.png
Greyscale
Fig. 10 of Bassill
Bassill teaches a negative peak value detection circuit (Fig. 10) electrically coupled with the resonant tank (337), wherein the negative peak value detection circuit detects the resonant tank current and the resonant voltage (337), and the negative peak value detection circuit acquires the negative peak current value according to the resonant tank current and the resonant tank voltage ([0098] value of Vsense 344 and thus to the RMS value of the input AC line voltage waveform 331).
Kagan, Heo, Morris, and Bassill are considered to be analogous to the claimed invention because they are in the same field of heaters and detection circuitry. It would have been obvious to have modified Kagan, Heo, and Morris to incorporate the teachings of Bassill to be able to provide a circuit that provides an effective way to perform digital control and accurately receive a negative peak value (Bassill [0098-0102]).
Regarding claim 5, Kagan, Heo, Morris, and Bassill teach the heating device according to claim 3, but Kagan and Morris are silent on wherein the negative peak value detection circuit comprises: a second current transformer, wherein an input terminal of the second current transformer is electrically coupled with the resonant tank to receive the resonant tank current; a third resistor, wherein a first terminal and a second terminal of the third resistor are electrically coupled with an output terminal of the second current transformer, and the second terminal of the third resistor is electrically coupled with a ground terminal; a negative feedback amplifier, wherein a non-inverting terminal of the negative feedback amplifier is electrically coupled with a first terminal of the third resistor and the output terminal of the second current transformer, and an inverting terminal of the negative feedback amplifier is electrically coupled with an output terminal of the negative feedback amplifier; a diode, wherein a cathode of the diode is electrically coupled with the output terminal of the negative feedback amplifier; a fourth resistor electrically coupled between an anode of the diode and the ground terminal; and a second capacitor electrically coupled between the anode of the diode and the ground terminal, wherein the second capacitor and the fourth resistor are electrically coupled with each other in parallel.
Heo teaches wherein the negative peak value detection circuit (1) comprises: a third resistor (resistors), wherein a first terminal and a second terminal of the third resistor are electrically coupled with an output terminal of the second current transformer (power source), and the second terminal of the third resistor is electrically coupled with a ground terminal;
a negative feedback amplifier (101), wherein a non-inverting terminal of the negative feedback amplifier is electrically coupled with a first terminal of the third resistor (resistors) and the output terminal of the second current transformer (power source), and an inverting terminal of the negative feedback amplifier is electrically coupled with an output terminal of the negative feedback amplifier (101);
a diode (102), wherein a cathode of the diode is electrically coupled with the output terminal of the negative feedback amplifier (101).
It would have been obvious to have modified Kagan to incorporate the teachings of Heo to have a resistor, negative feedback amplifier, and diode for the purposes of determining a negative peak current value as using negative peak current values simplifies digital calculation operations and use of blocks noise in further calculations (Heo [0009]).
Bassill teaches a second current transformer (338), wherein an input terminal of the second current transformer is electrically coupled with the resonant tank to receive the resonant tank current (337, taken to be the equivalent of a resonant tank); a fourth resistor (335) electrically coupled between an anode of the diode (334) and the ground terminal; and a second capacitor (333) electrically coupled between the anode of the diode and the ground terminal, wherein the second capacitor (333) and the fourth resistor (335) are electrically coupled with each other in parallel.
It would have been obvious to have modified Kagan, Heo, and Morris to incorporate the teachings of Bassill to have a transformer, another resistor and capacitor in order to be able to provide a circuit that provides an effective way to perform digital control and accurately receive a negative peak value (Bassill [0098-0102]).
Claim 4 is rejected under 35 U.S.C. 103 as being unpatentable over Kagan (US20080238386), Heo (KR20150108133A), Morris (US5073849A), and Bassill (US20030192881) as applied to claim 3 above, and further in view of Barrit (US5648008A).
Regarding claim 4, Kagan, Heo, Morris, and Bassill teach The heating device according to claim 3, but are silent on wherein the zero-crossing detection circuit comprises: a first current transformer, wherein an input terminal of the first current is electrically coupled with the resonant tank to receive the resonant tank current; a first resistor, wherein a first terminal and a second terminal of the first resistor are electrically coupled with an output terminal of the first current transformer, and the second terminal of the first resistor is electrically coupled with a ground terminal; a comparator, wherein a positive input terminal of the comparator is electrically coupled with the first terminal of the first resistor and the output terminal of the first current transformer, and a negative input terminal of the comparator is electrically coupled with the second terminal of the first resistor and the ground terminal; a second resistor electrically coupled between a voltage source and an output terminal of the comparator; a Zener diode, wherein an anode of the Zener diode is electrically coupled with the ground terminal, and a cathode of the Zener diode is electrically coupled with the output terminal of the comparator, and a first capacitor electrically coupled between the output terminal of the comparator and the ground terminal, wherein the first capacitor and the Zener diode are electrically coupled with each other in parallel.
Barritt teaches wherein the zero-crossing detection circuit (76, Fig.10A) comprises: a first current transformer (22), wherein an input terminal of the first current is electrically coupled with the resonant tank to receive the resonant tank current (18)
a first resistor (R3), wherein a first terminal and a second terminal of the first resistor are electrically coupled with an output terminal of the first current transformer (22), and the second terminal of the first resistor (R3) is electrically coupled with a ground terminal (GND);
a comparator (D4), wherein a positive input terminal of the comparator is electrically coupled with the first terminal of the first resistor (R3) and the output terminal of the first current transformer, and a negative input terminal of the comparator is electrically coupled with the second terminal of the first resistor and the ground terminal (R3);
a second resistor (R4) electrically coupled between a voltage source (VCC) and an output terminal of the comparator (D4);
a Zener diode (ZD2), wherein an anode of the Zener diode is electrically coupled with the ground terminal, and a cathode of the Zener diode is electrically coupled with the output terminal of the comparator (D4), and
a first capacitor (C7) electrically coupled between the output terminal of the comparator and the ground terminal, wherein the first capacitor (C7) and the Zener diode (ZD2) are electrically coupled with each other in parallel.
Kagan, Heo, Morris, Bassill, and Barritt are considered to be analogous to the claimed invention because they are in the same field of heaters and detection circuitry. It would have been obvious to have modified Kagan, Heo, Morris, and Bassill to incorporate the teachings of Barritt to have a zero crossing circuit such that an associated zero crossing pulse may be generated while coupled to the device such that n inverter may activated in response to a zero crossing signal (Barritt Col. 5 lines 1-15).
Claims 8 and 9 are rejected under 35 U.S.C. 103 as being unpatentable over Kagan (US20080238386), Heo (KR20150108133A), and Morris (US5073849A) as applied to claim 1 above, and further in view of Barritt (US5648008A).
Regarding claim 8, Kagan, Heo, and Morris teach the heating device according to claim 1, but are silent on wherein the heating device is an induction cooking stove.
PNG
media_image4.png
502
752
media_image4.png
Greyscale
Fig. 5 of Barritt
Barritt teaches wherein the heating device is an induction cooking stove (Col. 1 lines 10-20 induction cooking device).
It would have been obvious to have modified Kagan, Heo, and Morris to incorporate the teachings of Barritt to have the heating device be an induction cooking stove such that cooking operations may be optimized through the control by analog and digital circuits based on a location of the cookware (Barritt Col. 1 lines 5-10).
Regarding claim 9, Kagan, Heo, and Morris teach the heating device according to claim 1, but are silent on wherein the inverter circuit comprises an upper switch and a lower switch, which are connected with each other, wherein the upper switch and the lower switch are alternately turned on and turned off, and a first terminal and a second terminal of the resonant tank are electrically coupled with two conducting terminals of the lower switch, respectively.
Barritt teaches wherein the inverter circuit comprises an upper switch (44) and a lower switch (106), which are connected with each other (Fig.5), wherein the upper switch and the lower switch are alternately turned on and turned off (Col. 17 lines 25-40), and a first terminal and a second terminal of the resonant tank (18) are electrically coupled with two conducting terminals of the lower switch (106), respectively.
It would have been obvious to have modified Kagan, Heo, and Morris to incorporate the teachings of Barritt to have the inverter have a first and second switch that are alternately turned on an off such that unwanted portions of voltage are removed during operation, preventing related components to receive voltage signals when undesirable (Barritt Col. 17 lines 25-40).
Claims 6 and 7 are rejected under 35 U.S.C. 103 as being unpatentable over Kagan (US20080238386), Heo (KR20150108133A), Morris (US5073849A), Bassill (US20030192881), and Barrit (US5648008A) as applied to claim 4 above, and further in view of Shindoi (EP2437573B1) with citations made to attached machine translations.
Regarding claim 6, Kagan, Heo, Morris, Bassill, and Barrit teaches the heating device according to claim 4, and Kagan teaches wherein the detection unit (15) further comprises a microprocessor ([0115] one or more of a processor, microcontroller, analog discrete components, PC-based software, embedded signal processors, and/or other methods of electronic feedback and control processing), and a calculation unit (15)calculates the inductance of the resonant tank equivalent inductor (LL) according to the capacitance of the resonant tank capacitor (C), the resonant period provided by the zero-crossing detection circuit (tcross) and the first expression (equations 2.0 and 2.1), and the calculation (50) unit acquires the reference current value, the time difference (tmax) and the negative peak current value of the resonant tank current according to the resonant tank current (IL) and the resonant tank voltage (VL), the calculation unit (50) calculates the impedance value of the resonant tank (Rch) equivalent impedance according to the inductance of the resonant tank equivalent inductor (Lch), the time difference (tmax), the resonant period (tcross), the reference current value (IL), the negative peak value of the resonant tank current and the second expression (equation 6.5),
Kagan is silent on first calculation unit and a second calculation unit, wherein the first expression is previously stored in the first calculation unit, and the first calculation unit provides a first calculation result to the control unit, a second calculation unit, wherein the second expression is previously stored in the second calculation unit, wherein the second calculation unit acquires the first calculation result from the first calculation unit, and the second calculation unit provides a second calculation result to the control unit.
Shindoi teaches and the microprocessor (40, 50) comprises: a first calculation unit (40), wherein the first expression ([0025] 1) is previously stored in the first calculation unit (40), a second calculation unit (50), wherein the second expression ([0027-0028]) is previously stored in the second calculation unit (50), wherein the second calculation unit (50) acquires the first calculation result from the first calculation unit ([0026-0028]), and the second calculation unit (50) provides a second calculation result to the control unit (50, [0027] where the second calculation unit is also the controller).
It would have been obvious to have modified Kagan, Heo, Morris, Bassill, and Barrit to incorporate the teachings of Shindoi to have a microprocessor with a first and second calculation unit so that calculation regarding different aspects of the detected waveforms may be kept separate form each other (Shindoi [0028]).
Regarding claim 7, Kagan, Heo, Morris, Bassill, Barrit, and Shindoi teaches the heating device according to claim 6, and Kagan teaches wherein the microprocessor is a digital signal processor or a microcontroller unit ([0115] one or more of a processor, microcontroller, analog discrete components, PC-based software, embedded signal processors, and/or other methods of electronic feedback and control processing).
Response to Arguments
Applicant’s arguments, see Pg. 10 of the Remarks, filed 1/29/2026 with respect to the rejection of claim 1 in view of Kagan in view of Heo, regarding the amended limitation “the resonant tank operates in a discharge waveform in a negative half cycle,” have been fully considered and are persuasive. However, Applicant's amendment necessitated a new ground(s) of rejection presented in this Office action, wherein the new ground(s) of rejection is made in view of Kagan in view of Heo and further in view of newly cited reference Morris (US5073849A).
Applicant's arguments filed 1/29/2026, towards Kagan in Heo in view of amended limitation regarding the remaining amended limitations, have been fully considered but they are not persuasive. Regarding applicant's arguments that "Kagan fails to disclose or suggest that the measurement process begins after a specific inverter switch turn-off event that forces the resonant tank voltage to zero and then deliberately treats the subsequent waveform as a negative- half-cycle discharge waveform representing the natural response of the resonant tank," applicant's amended claims do not directly define the operation above. Kagan teaches a "turn off" event, of switch 30 in [0046] of the claims, where after both switches 20 and 30 are closed, switch 30 is opened, being the "turn off" event, where the voltage in the resonant tank would be understood to be zero, as all of the current is drawn to the charging capacitor 22, also described in [0046]. Kagan's calculations and measurements occur "after a switch of the inverter circuit is switched from a conducting state to a non-conducting state…," although not during the time when the " switch of the inverter circuit is switched from a conducting state to a non-conducting state." Kagan does not teach the limitation of " the resonant tank operates in a discharge waveform in a negative half cycle," however Morris is used to teach the limitation. And, in regards to the argument towards "the natural response of the resonant tank," applicant's claims do not recite the function of the detection unit, and given that the detection unit is able to determine the desired parameters on a discharge waveform, it would be reasonable to a POSTIA to be able to apply the teachings of Kagan in view of Heo and Morris to determine the characteristics of a waveform that indicated "the natural response of the resonant tank.
Regarding applicant's arguments that Heo "does not disclose using such a peak together with zero-crossing timing and a defined reference current at a voltage-zero time point to derive resonant tank equivalent inductance and equivalent impedance," Heo in combination with Kagan and Morris would teach the limitations, where Heo teaches the using the negative peak current values is valuable to simplify calculations, [0009] of Heo, so would be understood to, with Kagan and Morris to have been obvious to use to derive resonant tank equivalent inductance and equivalent impedance
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ABIGAIL RHUE whose telephone number is (571)272-4615. The examiner can normally be reached Monday - Friday, 10-6.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Helena Kosanovic can be reached at (571) 272-9059. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/ABIGAIL H RHUE/Examiner, Art Unit 3761 3/24/2026
/VY T NGUYEN/Examiner, Art Unit 3761