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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 02/06/2026 has been entered.
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.
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 16, 17, 19-21, and 25-31 are rejected under 35 U.S.C. 103 as being unpatentable over Stempfle (DE 10234898 A1) in view of Zhang (CN 112586482 A).
Regarding claim 16, Stempfle discloses an apparatus for combatting weeds with heated air (page 4, line 7, “The device can, for example, in the roof area for welding or activation of bitumen and plastic sheets but also for Weed control can be used”), said apparatus comprises:
a ventilator for creating an ambient air flow (fan motor 4; Fig. 1);
a burner for combustion of combustible gas (burner unit 2; Fig. 1), said burner obtaining combustion air being a first part of the ambient air flow from said ventilator, and providing an exhaust gas flow (page 3, lines 25-27, “After pressing the power switch, the fan motor [ 4 ] the required combustion air or cooling air from the outside via an axial suction opening. The axial suction opening is equipped with a protective grille [ 4.1 ] protected. The sucked-in air continues into the inside of the casing tube [ 1 ] where the airflow over the flow cone [ 2.7 ] hits the burner unit”);
an outlet tube to direct a heated air flow to weeds (jacket tube 1; Fig. 1), said heated air flow comprising the exhaust gas flow from said burner and a second part of the ambient air flow from said ventilator (page 3, lines 37 and 38, “Another part of the air flow flows through the space between the air tube sleeves 3.1 and 3.2, forms an annular surface and thus surrounds the open burner flame to the outside;” page 4, lines 1-5, “Another part of the air flow is connected to the outer air tube sleeve [ 3.1 ] to cool the inside of the jacket tube [ 1 ]. This largely prevents contact with the radiant heat of the burner flame. Immediately after exiting the burner unit, the air flows directed to the outside in the area of the tapering outlet opening [ 1.1 and 1.2 ] brought together again and heated up. The device is dimensioned so that the hot air generated can only escape through the predetermined outlet opening of the jacket tube”);
wherein said outlet tube comprises a mixing unit inside said outlet tube to mix said exhaust gas flow from said burner and said second part of the ambient air flow from said ventilator (air duct sleeves 3, 3.1, 3.2; Fig. 1 shows air duct sleeves 3, 3.1, 3.2 inside jacket tube 1).
Stempfle, however, fails to specifically disclose wherein said outlet tube comprises at least a first grid inside said outlet tube, and wherein the outlet tube further comprises at least a second grid present off stream the first grid.
Zhang is in the field of vegetation destruction and teaches wherein said outlet tube comprises at least a first grid inside said outlet tube (partition 240; page 5, lines 35 and 36, “through holes are uniformly arranged on the partition 240;” Fig. 3), and wherein the outlet tube further comprises at least a second grid present off stream the first grid (Zhang; cover plate 220; Fig. 3 shows cover plate 220 offset from partition 240).
Therefore, it would have been obvious to one of ordinary skill in the art of vegetation destruction before the effective filing date of the claimed invention to modify the device of Stempfle such that the outlet tube comprises at least a first grid inside said outlet tube, as taught by the grid structure of Zhang. The first grid would partition the buffer chamber from the air mixing chamber and the second grid would protect the mixing chamber from debris, which would improve the overall operation of the device. The modification would have a reasonable expectation of success.
Regarding claim 17, Stempfle in view of Zhang discloses the device of claim 16, and furthermore, the modified reference teaches wherein a perimeter of the first grid matches an inner wall of the outlet tube along a radial section at one position along a flow axis of the outlet tube (Zhang; Fig. 3 shows a perimeter of partition 240 matches at least one inner wall of box body 210 along a flow axis of air exiting the box body 210).
Regarding claim 19, Stempfle in view of Zhang discloses the device of claim 17, however, the modified reference fails to specifically disclose wherein openings of the first and second grid are not aligned in an axial direction of the outlet tube. However, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to modify Stempfle in view of Zhang such that the openings of the first and second grid are not aligned in an axial direction of the outlet tube in order to improve mixing. Additionally, it has been held that rearranging parts of an invention involves only routine skill in the art. See MPEP § 2144.04(VI)(C); In re Japikse, 86 USPQ 70 (CCPA 1950); In re Kuhle, 526 F.2d 553, 188 USPQ 7 (CCPA 1975).
Regarding claim 20, Stempfle in view of Zhang discloses the device of claim 16.
Stempfle discloses wherein the burner comprises a burner block (Fig. 1 show burner 2 comprises a burner block).
Regarding claim 21, Stempfle in view of Zhang discloses the device of claim 20.
Stempfle discloses wherein a gas valve is provided immediately upstream a combustible gas inlet of the burner block (page 3, lines 28 and 29, “When the gas valve [for example a solenoid valve] is opened, gas, for example propane gas or the like, is simultaneously supplied to the burner unit with a predetermined gas pressure via the preferably gas connection threaded sleeve [ 2.6 ]”).
Regarding claim 25, Stempfle in view of Zhang discloses a method to combat weeds with heated air, the method comprises: providing an apparatus according to claim 16 and carrying said apparatus in one of a right or left hand (Stempfle; page 5, lines 29 and 30, “the hot air device is designed such that it as a handheld device can be used”); providing combustible gas to said apparatus (Stempfle; page 3, lines 25-27); activating the burner of said apparatus such that an outlet air flow at an outlet opening of the apparatus is provided (Stempfle; page 3, lines 37 and 38); directing to and moving said outlet air flow along a surface on which the weeds are to be combatted (page 3, lines 37 and 38).
Regarding claim 26, Stempfle in view of Zhang discloses the method of claim 25.
Stempfle discloses wherein the temperature of the outlet air flow at the outlet opening of the apparatus is in the range of 130 to 300°C (page 3, lines 39 and 40, “The air is preferably heated so that it exits the outlet opening of the casing tube [ 1 ] can leave at a temperature up to about 1000 ° C”).
Regarding claim 27, Stempfle in view of Zhang discloses the method of claim 25, however, the modified reference fails to explicitly disclose wherein the outlet opening of the apparatus is moved along the surface at a speed of 5 to 50 cm/sec, however, in view of the structure disclosed by Stempfle on page 3, lines 37 and 38, the method of operating the device would have been inherent, since it is the normal and logical manner in which the device could be used. Furthermore, it would have been obvious to one having ordinary skill in the art at the earliest effective filing date of the invention to move the device along the surface at a speed of 5 to 50 cm/sec, in order to effectively treat weeds. Since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. In re Aller, 105 USPQ 233.
Regarding claim 28, Stempfle in view of Zhang discloses the method of claim 25.
Stempfle discloses wherein the combustible gas is propane (page 3, lines 28 and 29).
Regarding claim 29, Stempfle in view of Zhang discloses the method of claim 25.
Stempfle discloses wherein the combustible gas is provided from a hand-carried gas bottle (page 3, lines 29 and 30, “A corresponding gas hose is connected gas-tight with an adjustable pressure reducer as well as with a propane gas bottle and with a gas connection fitting on the device control box”).
Regarding claim 30, Stempfle in view of Zhang discloses the method of claim 29, however, the modified reference fails to explicitly disclose wherein said apparatus is carried in said one of the right or left hand, the hand-carried gas bottle is carried in another one of the right or left hand, however, in view of the structure disclosed by Stempfle on page 3, lines 29 and 30, the method of operating the device would have been inherent, since it is the normal and logical manner in which the device could be used. Furthermore, it would have been obvious to one having ordinary skill in the art at the earliest effective filing date of the invention to adjust the method such that where said apparatus is carried in said one of the right or left hand, the hand-carried gas bottle is carried in in another one of the right or left hand in order to optimize ergonomics of the method. Additionally, it has been held that the provision of adjustability, where needed, involves only routine skill in the art. In re Stevens, 101 USPQ 284 (CCPA 1954).
Regarding claim 31, Stempfle in view of Zhang discloses the device of claim 16, and furthermore, the modified reference teaches wherein a perimeter of the first grid matches an inner wall of the outlet tube (Zhang; Fig. 3 shows a perimeter of partition 240 matches at least one inner wall of box body 210 along a flow axis of air exiting the box body 210).
Claims 22-24 are rejected under 35 U.S.C. 103 as being unpatentable over Stempfle (DE 10234898 A1) and Zhang (CN 112586482 A) as applied to claim 20, and further in view of Forrester (US 11660358 B1).
Regarding claim 22, Stempfle in view of Zhang discloses the device of claim 20, including wherein the burner comprises a burner block having a hollow body having an elongated shape in an elongate direction (Stempfle; Fig. 1 shows burner 2 with a hollow, elongated body), the burner comprises a burner housing being a tubular housing with two open ends (Stempfle; Fig. 1 shows burner 2 is housed in a tube with two open ends), said burner block being provided in the burner housing, between the burner block and the burner housing, at least two inlet slots (Stempfle; air intake holes 2.2; Fig. 1), one along each side in elongated direction of the hollow body of the burner block are provided to allow air from the first part of the ambient air flow to flow along the burner block outer surface (Stempfle; air duct sleeves 3, 3.1, 3.2; Fig. 1; page 3, lines 37 and 38), however, Stempfle fails to specifically disclose said burner block being provided from polymeric material, or from aluminium or from an aluminium alloy.
Forrester is in the field of handheld gas combustion devices and teaches a burner block being provided from polymeric material, or from aluminium or from an aluminium alloy (Col. 4, lines 52-55, “Boiler 12 is fabricated from a material capable of conducting heat produced by burner 12 and with sufficient integrity to withstand the high temperatures created thereby. Exemplary materials include titanium, aluminum, steel and other similar metal alloys”).
Therefore, it would have been obvious to one of ordinary skill in the art of handheld gas combustion devices before the effective filing date of the claimed invention to modify the device of Stempfle in view of Zhang such that the burner block being provided from polymeric material, or from aluminium or from an aluminium alloy, as taught by the aluminum material of Forrester. The aluminum material would provide the burner with sufficient integrity to withstand the high temperatures, which would improve overall operation of the device. The modification would have a reasonable expectation of success.
Regarding claim 23, Stempfle in view of Zhang and Forrester discloses the device of claim 22, and furthermore, the modified reference teaches wherein the burner housing is provided from polymeric material, or aluminium or an aluminium alloy (Forrester; Col. 4, lines 52-55).
Regarding claim 24, Stempfle in view of Zhang and Forrester discloses the device of claim 22.
Stempfle discloses wherein the burner comprises a burner chamber, the burner block and the burner housing defining a part of the wall of the burner chamber (Fig. 1 shows burner 2 has an interior chamber with surrounding walls), the inlet slots are provided with air permeable plates to limit the inlet slot at the burner chamber (air intake holes 2.2; Fig. 1).
Response to Arguments
Applicant's arguments filed 02/06/2026 have been fully considered but they are not persuasive.
Regarding the argument on pages 8 and 9 that “Zhang teaches: ‘The cover plate 220 is arranged in a grid shape to prevent large stones, tree stumps and other debris from contacting the burner 230, and prevent the edge of the air flow channel on the burner 230 from being broken or blocked.’ As such, Zhang clearly teaches that the cover plate 220 is positioned in front of an opening of the air flow channel, not inside an outlet tube as required for the at least one grid of amended claim 16. For finding a teaching of at least a second grid present off stream the first grid, the rejection references clapboard 240 of Zhang. However, element 240 of Zhang is described and shown as a partition upstream of the burner, on a side of the burner away from the cover plate 220, for forming a buffer chamber 241 where gas may be compressed before passing to the air mixing chamber 211 and eventually the burner 230,” the Examiner submits that cover plate 220 is no longer relied upon to teach the first grid, but instead, partition 240 is relied upon to teach these features as partition 240 is “a first grid inside said outlet tube” as claimed. Furthermore, it is noted that cover plate 220 is now relied upon to teach the second grid, as it is “a second grid present off stream the first grid” as claimed, since the grids are off center from one another along their common flow axis. Therefore, the mixing unit as claimed is disclosed by Stempfle in view of Zhang.
Conclusion
The prior art made of record and not relied upon is considered pertinent to Applicant's disclosure.
Newson, US 20050143259 A1, discusses a thermal weed, fungal, insecticidal and sterilization method.
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/S.T.C./Examiner, Art Unit 3642
/JOSHUA D HUSON/Supervisory Patent Examiner, Art Unit 3642