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 .
Response to Final Office Action
Applicant's request for reconsideration of the finality of the rejection of the last Office action is persuasive and, therefore, the finality of that action is withdrawn.
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.
Claim(s) 34-36, 39, 41, 43-49, 51 and 53-58 is/are rejected under 35 U.S.C. 103 as being unpatentable over Palm et al (US 3,885,125) in view of McGraw (US 5,960,157) and Lutz, II (US 2015/0345826).
With respect to claims 34 and 54, Palm shows a burner vessel claimed including a vessel housing containing a combustible fuel burner (23) arranged to burn combustible fuel for heating fluid in one or more fluid circuits, a first cold fluid inlet (14), a first hot fluid outlet (15), a first fluid duct (defined by an inner shell 12 and an outer shell 13) extending between the first cold fluid inlet and the first hot fluid outlet, and a flue (27) arranged to convey waste combustion gas from the vessel wherein the combustible fuel burner is arranged to heat fluid in the first fluid duct (also, see Figure 1). Palm in another embodiment discloses that one or more electric heating elements (44) can be arranged in the fluid duct for directly heating the fluid as illustrated in Figure 7, but Palm does not show that one or more electric heating is used in combination with the combustible fuel burner for heating the fluid wherein one or more electric heating elements are able to provide heat in isolation to supply the demand without burning combustible fuel and that the heating elements are powered by a DC power supply via a controller as further recited in claim 54.
McGraw discloses it is known to provide a hybrid electric-combustible fuel fluid heater including a combustible fuel burner (38) and an electric heating element (62) for heating fluid in a water tank (22) wherein the electric heating element directly heats the fluid as the heating element is immersed in the water tank (22; also, see Figure 1), and McGraw further teaches that only the electric heating element can be selected without selecting the combustible fuel burner to meet the desired fluid/water temperature (column 3, lines 38-46). McGraw further shows a controller (26) to control an amount of heating applied by the combustible fuel burner and by the electric heating element via a processor (28; also see column 7, lines 37-43).
Lutz discloses it is known to power a resistive heating element (140) of a water heater (100) with an AC power outlet or by a battery source (para 0025).
In view of McGraw and Lutz, it would have been obvious to one of ordinary skill in the art to adapt Palm with one or more electric heating elements (44) that can be used for heating fluid in the fluid duct along with the combustible fuel burner which allows the user to select either the combustible gas burner or the electric heating elements in isolation with each other to predictably generate heat for heating fluid in the fluid duct, with the electric heating element to be in direct contact with the fluid as taught by McGraw along with the combustion heating, which allows operating either the electric heating element or the combustible fuel burner for cost saving purposes that depends on cost of operations wherein the electric heating element can be powered by a battery at taught by Lutz, which is known to be a DC power source, as alternative power source when a grid power/AC power becomes unavailable.
With respect to claims 35, 43 and 44, Palm discloses a plurality of fins (26) as a heat exchanger body that transfers heat from burnt fuel to the fluid and that surrounds a combustion zone (also, see Figure 3).
With respect to claim 36, Palm discloses the duct comprising at least one duct wall (inner or outer shell) through which heat is transferred from the burnt fuel to one or more fluid circuits (e.g., external heating system; column 3, lines 45-47).
With respect to claim 39, Palm shows a plurality of distinct electric heating elements in the duct as illustrated in Figures 5-7.
With respect to claim 41, Palm shows the electric heating element (44) that is located in the duct, and optionally spaced from the burnt fuel heat exchanger.
With respect to claims 45 and 46, Palm shows a housing with a cover or a multi-layer cover having at least one skin layer (outer layer) with one insulant layer (19) as illustrated in Figure 1 and 3.
With respect to claims 47-49 and 58, Palm shows the fluid duct (defined by an inner and outer shell/wall 12/13/18) that is provided as a channel defined or located entirely within the heat exchanger or a sealed pipe through a space or channel that is entirely within the heat exchanger that is between the wall and the cover as illustrated in Figures 1 and 3 forming a U shape (as shown by the walls 13/18), and Palm shows the electric heating element located within the fluid duct or the channel (Figure 7).
With respect to claim 51, Palm discloses the vessel housing containing at least one baffle (shown by a fin 26 that can restrain a flow of the heated gas/air) that would divert the heated air/gas which would increase thermal communication between the heated air and the duct wall.
With respect to claims 53, 55 and 56, McGraw discloses for the electric heating element that can be powered by AC power supply shown 120 VAC (36) wherein the controller (26) is arranged to control the supply of power to the electric heating element from the AC power supply; and Lutz discloses for the electric heating element that can be powered by a DC power supply such as a battery source.
With respect to claim 57, McGraw further discloses the controller to control the amount of heating supplied to the fluid based on a fluid temperature measured by a fluid temperature sensor (24) wherein Lutz discloses a DC power such as a battery that is known to power an electric heating element, and it would have been obvious to adapt Palm with the controller to further control an amount of heating supplied by increasing or decreasing the fuel or power delivered respectively to the fuel burner or the electric heating element, which can be powered by a DC power source, to predictably meet the desired fluid temperature demanded or desired by the user.
Claim(s) 50 is/are rejected under 35 U.S.C. 103 as being unpatentable over Palm in view of McGraw and Lutz as applied to claims 34-36, 39, 41, 43-49, 51 and 53-58 above, and further in view of Obst et al (US 2012/0315024).
Palm in view of McGraw and Lutz shows the burner vessel claimed except for the electric heating element in a spiraled wire element.
Obst shows it is known to provide an electric heating element for heating fluid wherein the electric heating element is in metal sheath formed of a spiral shaped wire element.
In view of Obst, it would have been obvious to one of ordinary skill in the art to adapt Palm, as modified by McGraw and Lutz, with the heating element in a metal sheathed element that is formed of a spiraled element as an alternative heating element structure that can also effectively heat the fluid as known in the art.
Claim(s) 52 is/are rejected under 35 U.S.C. 103 as being unpatentable over Palm in view of McGraw and Lutz as applied to claims 34-36, 39, 41, 43-49, 51 and 53-58 above, and further in view of Deivasigamani et al (US 2011/0041781).
Palm in view of McGraw and Lutz shows the burner vessel claimed except for the burnt vessel arranged to heat water in a first and second independent water circuits including a radiant heating and portable water heating.
Deivasigamani shows it is known to provide a fluid heated vessel that provides heated fluid to one or more fluid circuits including a radiant heating and a potable water heating as a first water circuit and as a second water circuit, respectively. Also, see para 0143.
In view of Deivasigamani, it would have been obvious to one of ordinary skill in the art to adapt Palm, as modified by McGraw and Lutz, with one or more water circuit including providing heating water to a radiator circuit or providing portable water heating, or any other water circuits where heated water would be predictably used to deliver heat as demanded or desired by the user.
Response to Arguments
Applicant’s arguments filed on 4/17/2026 with respect to McGraw have been fully considered and are persuasive. The finality of the last office action has been withdrawn as noted above.
Applicant’s arguments with respect to claim(s) have been considered but are deemed moot in view of the Lutz reference as stated in the ground of rejection.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to SANG Y PAIK whose telephone number is (571)272-4783. The examiner can normally be reached 9:00-5:30; M-F.
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/SANG Y PAIK/Primary Examiner, Art Unit 3761
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