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 § 112(b)
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1 and 3–13 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
The limitation of “non-negligible” in claim 1 is indefinite because the instant disclosure does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. The instant Spec. does not define a degree or given an idea regarding what is considered “non-negligible”. Based on applicant’s arguments in the Remarks dated May. 15, 2026, where it states “a common meaning of “negligible” on skilled in the art would understand “non-negligible” to mean that the different between the backwash position and the filtration position will produce at lest some effect, such as consequentially, cleaning cake from the filter”, Applicant Rem. p. 7, it is more confusing, because it is unclear what is “at least some effect…”.
Claims 3–13 are indefinite because they depend on claim 1.
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
The claims are rejected as follows:
Claims 1 and 3–13 are rejected under 35 U.S.C. 103 as being obvious over Barrett, US 2,057,814 A (“Barrett”) in view of Wagner et al., EP 3,444,018 A1 (“Wagner”)1.
Regarding claim 1:
Barrett discloses that a filter element (Barrett’s filter tube A) comprising a support body (Barrett’s body portion 1 and the plurality of arcuate elements 4) and a filter cloth (Barrett’s fabric covering 7B, Barrett, Figs. 1–2, p. 2, ll. 36–44 and ll. 68–71),
the filter cloth 7 being laid around the support body 1, 4 (Barrett discloses its fabric covering 7 is drawn to a tight condition in contact with the outer faces of the ridges between the grooves 5 of the arcuate element 4, Barrett Fig. 2, p. 2, ll. 71–75),
the support body 1, 4 comprises a dip channel that is centrally positioned (Barrett’s central passage 2) and outer longitudinal flow channels (Barrett’s grooves 5, Barrett Fig. 2, p. 2, ll. 36–40 and ll. 43–58),
Barrett discloses that the support body 1, 4 is formed of a continuous profile (Barrett disclose its support body 1 and 4 forms a continuous profile because there are no gaps in between, Barrett Fig. 2, p. 2, ll. 43–44),
Barrett also discloses that the outer longitudinal flow channels 5 are open radially towards an outside of the filter element (as best shown in Fig. 2, Barrett Fig. 2),
the filter cloth has a backwashing position and has a filtration position, the filtration position having a non-negligible volume difference from the backwashing position (noted here that this limitation describes intended use, and Barrett’s filter cloth is capable to move in response to the flow direction, i.e., in the filtration position, fluid flows from an outer circumference of the filter cloth and causing the filter cloth to move slightly inward, and in the backwashing position, the fluid comes from inside and causing the filter cloth to move slightly outward, which represents the non-negligible volume difference between the filtration and backwashing position, the limitation of “non-negligible” is interpreted as a difference that can be detected, i.e., any non-zero difference, since the instant disclosure does not provide a degree for the term “non-negligible”, Barrett Fig. 2; ).
Barrett does not disclose that the support body 1, 4 is formed of a continuous extruded profile. Barrett does not disclose that the support body comprises a thermoplastic material, a ceramic material or a metal.
In the analogous art of filter bag supporting systems, Wagner discloses a support body (Wagner’s support basket 6, Wagner Fig. 2, p. 3) inserted inside a filter bag 5 to support the filter bag 5, Wagner Fig. 2, p. 3. Wagner discloses its support basket is made of thermoplastic, Wagner p. 2. Wagner also discloses that its support body is an endless plastic extruded profile, Wagner Fig. 2, p. 1. Wagner discloses its support body made of plastic has the advantages of simplicity, flexibility, reduced weight, corrosion resistance, and cost reduction, and can be customized in design, Wagner p. 1. Wagner also discloses that a thermoplastic material is advantageous in particular by extrusion processable, with inherent flame resistance and excellent electrical properties, and impermeable to most liquids and gases and suitable for complex geometries, Wanger p. 2. It would therefore have been obvious for one ordinary skill in the art at the time of filing to modify Barrett’s support body 1, 4 to be made of Wagner’s thermoplastic with extrusion for the benefits disclosed. Note that at the time of Wagner’s invention, polymer/plastic technique has not been advanced as much to allow simple and integral processing, and a person of ordinary skill in the art would be motivated to use Wagner’s thermoplastic material and extrusion processing when those options become available.
Regarding claim 3:
Modified Barrett discloses that the filter element according to claim 1, wherein an outer contour of the support body is circular, star-shaped, cricket bat-shaped or elliptical (Barrett’s outer contour of the support body 1, 4 is star-shaped due to the plurality of grooves 5 provided at the outer surface of arcuate element 4). Barrett Fig. 2, p. 2, ll. 45–47.
Regarding claim 4:
Modified Barrett discloses that the filter element according to claim 1, wherein a central tube forms the dip channel (Barrett’s dip channel 2 is formed by a tubular body portion as shown in Fig. 1), and wherein longitudinal bars are mounted on the central tube (Barrett’s longitudinal ridges 5’ would read on the claimed” longitudinal bars” and they are mounted to the central tube because it is part of the arcuate member 4, which is secured to the body portion 1). Barrett Figs. 1 and 4, p. 2, ll. 43–44 and ll. 11–20 (2nd column).
Regarding claim 5:
Modified Barrett discloses that the filter element according to claim 1, wherein an outer longitudinal flow channel (one of Barrett’s grooves 5) is formed by a longitudinal wall (Barrett’s ridges 5’) within a material forming the support body (Barrett’s grooves 5 are defined by Barrett’s ridges 5 and both are part of Barrett’s arcuate element 4, and therefore they are formed of the same material of the claimed support body) with rounded outer edges (Barrett’s ridges 5 are rounded to accommodate the filter fabric 7 as best shown in Barrett’s Fig. 2) and being covered by the filter cloth 7. Barrett Fig. 2, p. 2, ll. 11–20.
Regarding claim 6:
It is noted that the published specification (hereinafter “Spec.”) teaches that the total differential volume shall mean the total volume (accessible for the filtrate) in the filter cloth in backwashing position minus the volume (accessible for the filtrate) of the channels covered by the filter cloth in the filtration position. Spec. [0044]. The examiner is interpreting the term “total differential volume” accordingly, where the “total differential volume” depends on the volume different of the outer longitudinal flow channels in backwash and filtration position.
Modified Barrett does not explicitly disclose that the filter element according to claim 1, wherein a volume of the dip channel 2 is at least 1% larger than a total differential volume of all outer longitudinal flow channels. However, Barrett discloses that its central longitudinal passageway 2 is in direct communication with the longitudinal circumferential grooves 5, Barrett Fig. 3, p. 2, ll. 32–38. It is therefore understood that the flow volume in dip channel 2 flows into/out of all the longitudinal circumferential grooves 5, It would therefore have been obvious for one ordinary skill in the art at the time of filing for the volume of the dip channel 2 to be at least 1% larger than a total differential volume of all outer longitudinal flow channels because it has to has the capability to accommodate all the flow from all the longitudinal circumferential grooves 5 regardless of its filtration and backwash position.
Additionally, the instant disclosure does not teach the claimed range is critical to the operation of the claimed invention. Therefore, absent evidence of criticality, this difference fails to patentably distinguish over prior art because it produces a difference in degree rather than in kind. MPEP 2044.05 (III)(A).
Regarding claim 7:
Modified Barrett discloses that the filter element according to claim 1, wherein the filter cloth is fixed on the filter element by cloth-fixing elements (Barrett’s elements 7’), one cloth-fixing element on a bottom end of a longitudinal channel area and one cloth-fixing element on a top end of the longitudinal channel area of the filter element (Barrett’s elements 7’ comprising two elements with one located on a top end and the other located on a bottom end of the fabric covering 7’ and thus aid in securing the fabric covering in place). Barrett Fig. 1, p. 2, ll. 58–64 (2nd column).
While Barrett does not explicitly disclose that the cloth-fixing elements 7 seal the filtrate room against the feed room, Barrett’s element 7’ necessarily need to provide a seal function to prevent unfiltered fluid bypass the fabric covering 7 and enter grooves 5.
Regarding claim 8:
Modified Barrett discloses that the filter element according to claim 1, wherein the filter element further comprises a coupling part (portion of Barrett’s head 9 proximate Barrett’s inclined upper face 9a) located between the support body 1 and a fixing device (Barrett’s elements 7’) and a pin (Barrett’s pin 1a) for alignment of the filter element A (intended use, and Barrett’s pin 1a is capable of aligning the filter element A with Barrett’s head 9, which is part of the filter element because Barrett’s pin 1a passing through a portion of head 9 and into body portion 1, and therefore align those two parts) in a filter device (device as shown in Barrett’s Fig. 1). Barrett Fig. 1, p. 2, ll. 31–38 (2nd column).
Regarding claim 9:
Modified Barrett discloses that the filter element according to claim 8, wherein the filter cloth is fixed above the coupling part to cover the pin and the coupling part (as best shown in Barrett’s Fig. 3, Barrett’s fabric covering 7 covers the coupling part and pin 1a). Barrett Fig. 3, p. 2, ll. 31–38 (2nd column).
Regarding claim 10:
Modified Barrett discloses that the filter element according to claim 15, wherein the thermoplastic material is a compound material containing stability-enhancing additives including carbon fibers or glass fibers (Wagner discloses its thermoplastic material is fiber-reinforced with suitable fibers being glass fibers and/or carbon fibers, Wagner p. 2).
Regarding claim 11:
Modified Barrett discloses that a filter device comprising one or more filter elements, each of the one or more filter element being configured as the filter element of claim 1, wherein the filter device (as shown in Fig. 1) is a vessel (because Barrett’s filter device is a hollow container) in which unfiltered fluid (located outside of fabric covering 7) is separated from filtered fluid (inside fabric covering 7) by a head plate (Barrett’s head 12, which is shown as a flat disc and therefore would read on the claimed plate, and Barrett’s head 12 covers top of Barrett’s fabric covering 7 and therefore isolates external unfiltered fluid from internal filtered plate). Barrett Fig. 1, p. 2, ll. 39–43 (2nd column).
Regarding claim 12:
Modified Barrett discloses that the filter device of claim 11, wherein the one or more of the filter elements are mounted on one or more common filtrate headers (Barrett’s flanged conductor 15) as collector tubes (Barrett’s flanged conductor 15 would read on the collector tubes because they are tube shaped and are configured to collect filtered fluid). Barrett Fig. 1, p. 2, ll. 50–57 (2nd column).
Regarding claim 13:
Modified Barrett discloses that the filter element of claim 1, wherein the filter element is used in a system configuration where one or more of the filter elements are mounted on tube headers (Barrett’s flanged conductor 15) and are submerged in a feed contained in an open basin (Barrett discloses its tube filter is suspended in the liquid or semiliquid contained within the receptacle or suitable tank, the receptable or suitable tank would read on the claimed “open basin) and wherein a differential pressure needed to drive filtration is created by a vacuum inside the tube headers (Barrett discloses its flanged conductor 15 is connected to means for creating vacuum within the passage 2 and grooves 5 and means for forcing air through said passageway 2 and grooves 5). Barrett Fig. 1, p. 1, ll. 11–16 and p. 2, ll. 50–57.
Response to Arguments
Claim Rejections - 35 USC § 112(b)
The applicant traverses the current 35 USC § 112(b) rejection. The applicant argues that the MPEP section the examiner cited is in error, because it directly to “substantially” rather than “non-negligible”, Applicant Rem. dated May. 15, 2026 (“Applicant Rem.”) p. 2. In addition to that, the applicant argues that the term “non-negligible” in the instant application means that the different between the backwash position and filtration position will produce “at least some effect, such as, consequentially, cleaning fake from the filter”, Id. Additionally, the applicant argues that the instant Spec. provides what “non-negligible” means, because it describes the dip channels volume must be greater than 1% the total differential volume, which is the filter cloth in the backwashing position minus the volume of the channels covered by the filter cloth in the filtration position, Id. at p. 8. The applicant argues that since the Spec. discloses that the dip channel volume has to be large enough to compensate for the volume created between a fully inflated filter cloth and its support structure during backwash to compensate the volume enlargement of the mentioned room caused by the backwash. The applicant further cites to the Spec., where it is stated that the limitation "the filtration position having a non- negligible volume difference from the backwashing position" is tied, in the specification, to a specific measurable parameter, where preferred embodiments are configured so that the filter element is larger than the difference between the filtration position and the backwash position by at least 1%, Id. at ps. 8–9.
In response, the examiner maintains the rejection regarding the term “non-negligible” being indefinite because the instant disclosure does not provide how big the difference has to be to be considered “non-negligible”. In fact, the instant Spec. does not use the term “non-negligible”. The MPEP section is the closet the examiner could find to give the applicant an idea. Similar to the case law cited by the applicant, which is not about a filter, rather, the case law is about illumination patterns. Yet, the applicant relies on such case law to illustrate his point. Furthermore, regarding applicant’s effort to look up the term in dictionary, it is pointed out here that the term “non-negligible” in the context of science, mathematics or engineering, has been refers to a quantity that is non-zero2. Under such interpretation, it is pointed out that the rejection is made to give the applicant a chance to better define the volume difference to overcome the prior art, because a “non-zero” volume difference between the filtration and backwash position is easily met based on completely opposite flow volume directions.
Additionally, regarding applicant’s arguments about that the instant Spec. provides support for the term “non-negligible” because it is stated that its volume of dip channel has to be large enough to compensate for the difference between the filtration position and the backwash position, the examiner respectfully disagrees. The instant Spec. relies on the difference between the filtration and backwash positions to define the volume of the dip channel, not the other way around. And since it is not clear what is the claimed “non-negligible” volume difference, it further renders the volume of the dip channel unclear. The instant Spec. does not disclose a volume of its dip channel, so it is also not possible to work backwards to deduce what would be the volume difference between the filtration and backwash position.
Applicant’s argument is therefore not convincing.
Claim Rejections - 35 USC § 103
The applicant argues about claim 15, Applicant Rem. p. 9. It is pointed out that claim 15 is cancelled, and therefore beyond the scope of discussion.
Nevertheless, the examiner would like to specifically address applicant’s concern regarding the term “non-negligible”, Applicant Rem. ps. 10–11. The term “non-negligible” is interpreted as “non-zero” lacking of clear definition in the Spec. It is also pointed out here that the published Spec. seems to relates its more efficient backwashing to lower resistance against the liquid flow or respectively gas flow during filtration operation and backwashing, Spec. [0037]. The instant Spec. does not have clear statement ties a “non-negligible” volume difference between filtration operation and backwashing to backwashing efficiency, which applicant’s arguments heavily focuses on. And since the proposed rejection read on all the claimed limitation, an allowance cannot be entered.
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to QIANPING HE whose telephone number is (571)272-8385. The examiner can normally be reached on 7:30-5:00 M-F.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Jennifer Dieterle can be reached on (571) 270-7872. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/Qianping He/Examiner, Art Unit 1776
1 A copy of Wagner’s original document and machine translation are provided with the office action. The examiner relies on the original document for the text and machine translation for the figure.
2is non-negiligible a subjective term - Search
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