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 .
Information Disclosure Statement
The information disclosure statements (IDS) submitted on 02/11/26 are in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statements are being considered by the examiner.
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.
Claim(s) 1 and 6, 11-13, 15-17 and 19 is/are rejected under 35 U.S.C. 103 as being unpatentable over Barr et al., U.S. Patent 2015/0247511 (hereinafter “Barr”) in view of Wang et al., Chinese Patent Publication CN104454677 (hereinafter “Wang”).
In Reference to Claim 1:
Barr discloses a hydraulic tank (Figure 2,3-5) comprising at least one side wall comprising an inlet for receiving hydraulic fluid (See, Schematic in Figure 2 which shows an inlet received from the case drain lines 218 of the motor and 212 of the pump; See also Figure 5 which shows it on the angular side wall) from a hydraulic actuation circuit (Figure 2 featuring actuators 106 and cooling motor 216), an outlet for providing hydraulic fluid to the hydraulic actuation circuit (via 207), and a drain line inlet (See, Figure 3 which shows multiple inlets (return line 306), Figure 2 also shows an additional inlet passed through filter 116) ; a filter disc (500 and 502) comprising a filter media in the form of a mesh to filter out material and wherein the filter media is spaced apart from the port
Barr fails to disclose a port plate comprising at least one drain port , the port plate being attached to the at least one side wall over the drain line inlet, the filter disc being disposed between the port plate and the drain line inlet; and a gasket positioned around the filter disc and disposed between the port plate and the at least one side wall; this is because the filtration of Barr is not conducted external to the housing but internal such that the filtration occurs at the end of the line and therefore there is no port plate or gasket required
However, in the same field of endeavor, Wang disclose a hydraulic tank wherein the filter is mounted externally for filtering in hydraulic fluid and therefore contains a port plate (although not shown inherent for the oil line to connect to the external filter for the conduit to be attached, a gasket ( also not shown but inherent to seal between the external filtration and the housing otherwise it would leak) and a filter disc (inherent as it’s a filter).
It would have been obvious to a person having ordinary skill in the art at the time of effective filing to modify Barr to include the teachings of Wang, specifically to modify the pre-existing filtration present in Barr, such that the filtration is placed externally and therefore contains a port plate to attach the returning hydraulic fluid and guide it into the external filter and a sealing gasket between the external filter to prevent leakage because such a modification would allow for easier maintenance on the filter should it need to be cleaner or replaced when it becomes debris laden by allowing for external access and also requiring one filter replacement of Wang versus the several mesh filters of Barr.
In Reference to Claim 6:
Barr further discloses wherein the port plate and the at least one side wall are separated by a distance D and wherein the filter media is spaced apart from the port plate by a first spacing S1 in a range 0D < S1 ≤ 1D. Examiner notes that this limitation without additional detail is not really limiting beyond suggesting that the port plate, side wall and filter media are all separate components which is taught by the prior art. Given that they are all separate components each of them is separated a distance apart. Applicant has not defined the distance D and therefore the range of OD to 1D is not limiting to a specific distance.
In Reference to Claim 11:
Barr further discloses the use of a mesh screen (500 and 502) to filter the drain case for the motor and the pump.
In Reference to Claim 12:
Examiner notes it would have been obvious to a person having ordinary skill in the art at the time of effective filing to have the mesh screen used for filtration of particles have a size range from 20 mesh to 250 mesh as a matter of design choice to filter out the typical particles associated with lubrication from the case drain and use of the hydraulic system. Examiner has reviewed the specification and Applicant has failed to establish any criticality to a mesh size.
In Reference to Claim 13
Barr as modified further discloses wherein the drain line inlet comprises a plurality of substantially parallel slits, a semicircular aperture, or a circular aperture. See, Wang Figure which illustrates a circle aperture.
In Reference to claim 15 and 16:
Barr as modified further discloses at least one actuator said actuator being a hydraulic motor (motor 216); a pump (110) configured to draw the hydraulic fluid from the outlet of the hydraulic tank (222) and pressurize the hydraulic fluid for actuation of the at least one actuator (106 or 216), the actuation causing return of hydraulic fluid to the inlet of the hydraulic tank (See, Figure 2); wherein a first portion of the hydraulic fluid flowing through the pump lubricates the pump, the first portion of the hydraulic fluid being returned to the hydraulic tank through a first drain line (via case drain 212 for allowing the leaked fluid that lubricates the pump to return to the tank) in fluid communication with the at least one drain port (return via 214); and wherein a second portion of hydraulic fluid flowing through the motor (216) lubricates the motor (via leakage and drainage through case drain (See, Figure 2) and the second portion of the hydraulic fluid is returned (via 220) to the hydraulic tank (222) through a second drain line in fluid communication with the at least on drain port.
In Reference to Claim 17:
Barr discloses a method for filtering hydraulic fluid on a drain line comprising: drawing the hydraulic fluid from a hydraulic tank (222) through a pump (110) ; using a first potion of the hydraulic fluid to lubricate the pump (via leaked fluid not shown but the purpose of the case drain is for draining lubricated fluid out) ; pressurizing the fluid using the pump (110), a second portion of the hydraulic fluid for use by at least one actuator (motor 216 or actuator 106) returning the first portion of the hydraulic fluid from the pump to the hydraulic tank through the drain line (212); filtering the first portion of the hydraulic fluid as the first portion of the hydraulic fluid flows into a drain line inlet of the hydraulic tank by passing the first portion of the hydraulic fluid through a filter media disposed over the drain line inlet;
Barr fails to disclose a port plate comprising at least one drain port , the port plate being attached to the at least one side wall over the drain line inlet, the filter disc being disposed between the port plate and the drain line inlet; and a gasket positioned around the filter disc and disposed between the port plate and the at least one side wall; this is because the filtration of Barr is not conducted external to the housing but internal such that the filtration occurs at the end of the line and therefore there is no port plate or gasket required
However, in the same field of endeavor, Wang disclose a hydraulic tank wherein the filter is mounted externally for filtering in hydraulic fluid and therefore contains a port plate (although not shown inherent for the oil line to connect to the external filter for the conduit to be attached, a gasket ( also not shown but inherent to seal between the external filtration and the housing otherwise it would leak) and a filter disc (inherent as it’s a filter).
It would have been obvious to a person having ordinary skill in the art at the time of effective filing to modify Barr to include the teachings of Wang, specifically to modify the pre-existing filtration present in Barr, such that the filtration is placed externally and therefore contains a port plate to attach the returning hydraulic fluid and guide it into the external filter and a sealing gasket between the external filter to prevent leakage because such a modification would allow for easier maintenance on the filter should it need to be cleaner or replaced when it becomes debris laden by allowing for external access and also requiring one filter replacement of Wang versus the several mesh filters of Barr.
In Reference to claim 19:
Barr as modified further discloses at least one actuator said actuator being a hydraulic motor (motor 216); wherein the second portion of the hydraulic fluid comprises a third portion of the hydraulic fluid, and wherein the method further comprises: using the third portion of the hydraulic fluid to lubricate the motor (216: via leaked fluid within the case drain that is drained to the tank); returning the third portion of the hydraulic fluid from the motor to the hydraulic tank through a second drain line; filtering the third portion of the hydraulic fluid as the third portion of hydraulic fluid flows into the drain line inlet of the hydraulic tank by passing the third portion of hydraulic fluid through the filter (206) media disposed over the drain line inlet; wherein the second drain line terminates at the port plate attached to the hydraulic tank (222). See, Figure 2 of Barr.
Claim(s) 2-4 and 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Barr et al., U.S. Patent 2015/0247511 (hereinafter “Barr”) in view of Wang et al., Chinese Patent Publication CN104454677 (hereinafter “Wang”) in further view of Ishikawa, Japanese Patent JP2750131 (hereinafter “Ishikawa”)
In Reference to Claim 2:
Barr as modified discloses all the limitations recited in claim 1 and 19, respectively, and further discloses wherein the filter media comprises a first flow area (inherent despite not being shown in Barr/Wang, as a filter must have a flow area) and the drain port comprises a second flow area (also inherent as the fluid must come from a conduit to get to the filter as illustrated in Barr and therefore has a flow area), but fails to explicitly disclose the first flow area is greater than the second flow area.
However, in the same field of endeavor, filtration for hydraulic oil circuits to remove debris, Ishikawa discloses a filter wherein the first flow area (filter medium) is greater than the second flow area (inlet to the filter -6).
Examiner notes it would have been obvious to a person having ordinary skill in the art at the time of effective filing to further modify Barr with the teachings of Ishikawa, namely to include a filter wherein the filter medium contains a larger flow area than that of the inlet flow area of the fluid because the filter introduces resistance of fluid movement during filtration and thereby requires a larger surface area to make up for the slower flow rate created during filtration otherwise there would be a significant loss in efficiency to the system and potential cavitation, especially when the filter becomes debris laden.
In Reference to Claim 3-4 and 20:
Barr as modified further discloses wherein the at least one drain port comprises a plurality of drain ports with several drain lines. See, Barr Figure 2 which illustrates a plurality of drain ports coming into the reservoir at a central location each drain port having a filter. However as discussed above upon modification with Wang a single external filter would be utilized containing a plurality of drain ports connected to the filter thereby meeting claim 33.
Examiner notes it would be obvious to a person having ordinary skill in the art at the time of effective filing to product wherein the plurality of drain ports comprises a combined flow area and wherein the first flow area is greater than the combined flow area because the filter introduces resistance of fluid movement during filtration and thereby requires a larger surface area to make up for the slower flow rate created during filtration otherwise there would be a significant loss in efficiency and cavitation in the system during filtration if the filter did not contain a larger surface area than that of the inlet pipes, this would be especially true when the filter becomes debris laden.
Claims 5 is rejected under 35 U.S.C. 103 as being unpatentable over Barr et al., U.S. Patent 2015/0247511 (hereinafter “Barr”) in view of Wang et al., Chinese Patent Publication CN104454677 (hereinafter “Wang”) in further view of Oler, U.S. Patent Publication 2021/0291093 (hereinafter “Oler”).
In Reference to claim 5:
Barr as modified discloses all the limitations of claim 1, but fails to disclose a positioning ring disposed within the gasket that spaces the filter media apart from the port plate.
However, in the same field of endeavor, fluid filtration utilizing disc filters, Oler discloses a disk filter with position rings (28) on both sides of the filter media and wherein said position ring is disposed within the gasket space. See, Figure 1 and 2.
It would have been obvious to a person having ordinary skill in the art at the time of effective filing to further modify the filter of Barr with the teachings of Oler, spefically modifying the filter such that it contains support positioning rings placed within the gasket housing as taught by Oler in Figure 2 because such a modification as discussed by Oler provides the distinct advantage of reduced filter failure in high pressure situations by having additional support thereby reducing deformation that typically occurs around the outside edge leading to early failure. See, Paragraph [0014] of Oler.
Claim(s) 7-10 and 18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Barr et al., U.S. Patent 2015/0247511 (hereinafter “Barr”) in view of Wang et al., Chinese Patent Publication CN104454677 (hereinafter “Wang”) in further view of McEwen, WIPO Publicaton WO9611735 (hereinafter “McEwen”).
In Reference to Claim 7-10 and 18:
Barr as modified discloses all the limitation of claim 1, but fails to disclose a supporting disc disposed between the filter media and the drain line inlet wherein the supporting disc spaces the filter media from the at least one side wall by a second spacing S2 in a range 0D < S2 < 1D. and wherein the supporting disc comprises an outer ring and a plurality of inwardly extending fingers configured to support the filter media and comprises an inner ring concentric with the outer ring, the fingers extending from the outer ring to the inner ring.
However, in the same field of endeavor, disc filters, McEwen discloses a disc filter wherein the supporting disc (110) spaced the filter media (114) and the drain line inlet wherein the supporting disc (110) spaces the filter media (114) from the at least one side wall by a second spacing S2 in a range 0D < S2 < 1D (Examiner notes that this limitation without additional detail is not really limiting beyond suggesting that the supporting disc, and filter media are all separate components which is taught by the prior art. Given that they are all separate components each of them is separated a distance apart. Applicant has not defined the distance D and therefore the range of OD to 1D is not limiting to any specific distance or spacing) and wherein the supporting disc (110) comprises an outer ring and a plurality of inwardly extending fingers configured to support the filter media and comprises an inner ring concentric with the outer ring, the fingers extending from the outer ring to the inner ring. See, Figure 11.
It would have been obvious to a person having ordinary skill in the art at the time of effective filing to further modify Barr, to include a disc filter as taught by McEwen in Figure 11 because such a modification would provide for a filter that has greater support than the filter disclosed by Wang providing for a more durable filter and one that can withstand a higher pressure due to the supporting disc.
Allowable Subject Matter
Claim 14 is 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.
Claim 14 recites the limitation of comprising a bleed hole disposed above the drain line inlet, each of the at least one bleed hole being covered by the port plate which is not taught by the prior art.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to DANIEL S. COLLINS whose telephone number is (313)446-6535. The examiner can normally be reached M-TH 8:00-5:30.
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/DANIEL S COLLINS/Examiner, Art Unit 3745
/NATHANIEL E WIEHE/Supervisory Patent Examiner, Art Unit 3745
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