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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 April 2nd, 2026 has been entered.
Response to Amendment
The amendment filed April 2nd, 2026 has been entered. Claims 1, 4-8, and 10-12 remain pending in the application. The amendments to the claims have overcome each and every 112(b) rejection previously set forth in the Final Office Action mailed February 3rd, 2026.
Response to Arguments
Applicant’s arguments, see Applicant Arguments/Remarks, filed April 2nd, 2026, with respect to the rejection of claims 1, 4-5, and 7 under 35 U.S.C. 102(a)(2) have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground of rejection is made under 35 U.S.C. 103 in view of U.S. Patent Publication No. US 2018/0117515 A1 to Hugues.
Claim Objections
Claim 1 is objected to because of the following informalities:
In claim 1, it appears as though a grammatical error was made when amending said claim and “wherein the side plates are formed by trapezoidal lateral, wherein” should read “wherein the side plates are formed by trapezoidal lateral surfaces, wherein”
Appropriate correction is required.
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.
Claims 1 and 4-7 are rejected under 35 U.S.C. 103 as being unpatentable over U.S. Patent Publication No. US 2018/0117515 A1 to Hugues (hereinafter referred to as Hugues).
Regarding claim 1, Hugues teaches a cassette filter (Fig. 1) comprising: a plurality of filter media packs (Fig. 1, media packs 104); and a frame for receiving the filter media packs (Fig. 1, filter frame 102), wherein in each case two filter media packs are arranged in a v-shaped manner (¶0043 “The media packs 104 are arranged side by side, leaning alternately to one side and to the other side, thereby forming a zigzag structure. More particularly, they are arranged in pairs, each pair forming a V shape”), wherein the frame includes an inflow-side head plate defining a first plane (Fig. 1, front plate 110), an outflow-side foot plate defining a second plane parallel to the first plane (Fig. 1, rear plate 114 is parallel with front plate 110), and two side plates (Fig. 1, side plates 112a and 112b), wherein the side plates are formed by trapezoidal lateral surfaces (¶0043 “Also, the side plates 112 may not have V-shaped portions at all but may for example be provided in the form of covering having a rectangular or trapezoidal shape”), wherein a plurality of strut-shaped air guiding elements are arranged in at least one cavity between limbs of the trapezoidal lateral surfaces which adjoin one another (Fig. 2, reinforcing elements 154), and wherein each row of the air guiding elements comprises a plane that is parallel to the first and second planes (see annotated figure below).
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Hugues does not teach wherein the plurality of strut-shaped air guiding elements are arranged in two rows. However, Hugues teaches that the reinforcing elements further increase the structural rigidity of the side plate (¶0043 “Reinforcing elements 154 may be provided extending between two adjacent V-shaped portions to further increase the structural rigidity of the side plate 112.”). It therefore would have been obvious to one of ordinary skill in the art that the inclusion of additional reinforcement elements would result in increased structural stability. Furthermore, mere duplication of parts has no patentable significance unless a new and unexpected result is produced. See MPEP § 2144.04 (VI)(B). With such a modification, both the first and second row of the air guiding elements would comprise a plane that is parallel to the first and second planes (see annotated figure below).
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Regarding claim 4, Hugues teaches the cassette filter as applied to claim 1 above, wherein the air guiding elements have guiding surfaces with different inclinations. As can be seen in Fig. 1 of Hugues, reinforcing elements 154 are depicted with slight curves on the bottom side and a straight surface on the lateral side, therefore reading on the limitation “wherein the air guiding elements have guiding surfaces with different inclinations” of claim 4. See annotated figure below.
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Regarding claim 5, Hugues teaches the cassette filter as applied to claim 1 above. As to the limitation “wherein the air guiding elements are formed as blades”, the Examiner has taken to the instant specification to determine how the Applicant defines a “blade” shape. According to ¶0026 of the instant specification, “the air guiding elements are formed as blades, namely with a cross-sectional profile in the form of an oval or a supporting surface.” As can be seen in Fig. 2 of Hugues, reinforcing elements 154 have a slight curvature to their profile and therefore read on “a cross-sectional profile in the form of an oval” and subsequently the limitation “wherein the air guiding elements are formed as blades.”
Regarding claim 6, Hugues teaches the cassette filter as applied to claim 1 above. Hugues further teaches wherein reinforcing elements 154 can be used as handles (¶0043 “These reinforcing elements 154 can also serve as handles when handling the side plates 112 or assembled filter frame assemblies 100.”). Although Hugues does not teach wherein the air guiding elements are adjustable in their orientation, it would have been obvious to one of ordinary skill in the art that adjustability would provide beneficial when maneuvering the assembled filter frame for use or when handling the side plates during assembly. Furthermore, adjustability, where needed, is not a patentable advance. See MPEP § 2144.04 (V)(D).
Regarding claim 7, Hugues teaches the cassette filter as applied to claim 1 above, wherein the head plate and the foot plate have in each case plate-shaped cross members assigned to the filter media packs (Fig. 3, parallel troughs 120b of front plate 110; Fig. 2, plate elements 116 of rear plate 114), and wherein flanks of the cross members of the head plate and/or the foot plate are embodied in a bulbous manner (Fig. 2, parallel troughs 120b of front plate 110 are adjacent to support structures 150a, 150b, which read on the “flanks”; Fig. 4a and 4b show the curvature of support structures 150, which protrude upwards in a rounded way and therefore read on the “bulbous manner” limitation of claim 7).
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Hugues as applied to claim 1 above, and further in view of U.S. Patent Application No. 2015/0322859 to Van Den Bossche et al. (hereinafter referred to as Van Den Bossche).
Regarding claim 8, Hugues teaches the cassette filter as applied to claim 1 above. Hugues further teaches wherein the cassette filter can be used in a gas turbine system (¶0005 “In high gas flow applications, e.g. in gas turbine systems, filter assemblies … are subjected to high external forces which can cause deformation of the filter assembly, resulting in gas leakage between the parts of the filter assembly or between the filter assembly and the filter holding structure.” ; ¶0006 “It is an object of the present invention to provide a filter frame … that has improved resistance to deformation of the filter assembly in high gas flow applications.”), but Hugues does not disclose how the filter is inserted in such a system.
However, Van Den Bossche teaches a tube sheet (Fig. 6, tube sheet 44) to receive filter elements within a gas turbine (Abstract “A tube sheet for the air intake for a gas turbine includes a non-planar frame arrangement with openings to receive filter elements.”), which reads on the limitation of a “filter wall” and wherein said filters are received in a “matrix-like manner.”
Hugues and Van Den Bossche are considered analogous to the claimed invention because they are in the same field of cassette filter assemblies. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the cassette filter as taught by Hugues could be inserted into a gas turbine system using the tube sheet as taught by Van Den Bossche, allowing for insertion of multiple filter systems at once (Fig. 6 of Van Den Bossche, openings 48). Furthermore, the use of the cassette filters as taught by Hugues in a gas turbine system as taught by Van Den Bossche would decrease potential gas leakage throughout the filter elements with the filter assembly that has improved resistance to deformation caused by high gas flow applications.
Allowable Subject Matter
Claims 10-12 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.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to RACHEL MARIE SLAUGOVSKY whose telephone number is (571)272-0188. The examiner can normally be reached Monday - Friday 8:30 am - 5:30 pm EST.
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/RACHEL MARIE SLAUGOVSKY/Examiner, Art Unit 1776
/Jennifer Dieterle/Supervisory Patent Examiner, Art Unit 1776
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