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 Amendment
This office action is responsive to the amendment filed on 23 December 2025. As directed by the amendment: claims 1, 12, 13 & 20 have been amended, claims 9, 10, 17 & 18 have been cancelled, and claims 21-24 have been added. Thus, claims 1-8, 11-16 & 19-24 are presently pending in this application.
It is noted that claim 12 is provided with a status indicator of “Original” but is clearly amended. This amendment is also referenced in applicant’s accompanying remarks. As such, the status identifier of claim 12 is understood to be an error, and the claim will be treated as “Currently Amended”. There is also a typographical error in the status indicator for claim 9.
Applicant is reminded that proper status indicators are required by 37 CFR 1.121(c). Amendments with incorrect or missing status indicators may be denied entry due to non-compliance. See MPEP § 714(II)(C) and MPEP § 714(II)(F).
Drawings
The drawings are objected to under 37 CFR 1.83(a). The drawings must show every feature of the invention specified in the claims. Therefore, the “at least one fluid channel…defined in one or more of the compressible member, the stop, and the second piston… configured to ensure oil is not isolated in a radially outer side of the compressible member” must be shown or the features canceled from the claims.
No new matter should be entered.
Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. The figure or figure number of an amended drawing should not be labeled as “amended.” If a drawing figure is to be canceled, the appropriate figure must be removed from the replacement sheet, and where necessary, the remaining figures must be renumbered and appropriate changes made to the brief description of the several views of the drawings for consistency. Additional replacement sheets may be necessary to show the renumbering of the remaining figures. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance.
Specification
The disclosure is objected to because of the following informalities:
The last sentence of paragraph 81 is cut off and appears to be missing at least some intended portion.
Appropriate correction is required.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 8, 11, 16 & 19 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Claims 1 & 13 have been amended to require “at least one fluid channel…defined in one or more of the compressible member, the stop, and the piston, the at least one fluid channel configured to ensure oil is not isolated in a radially outer side of the compressible member”.
As noted in applicant’s accompanying remarks, support for such an amendment is found in paragraph 83 of the specification. When read in appropriate context, paragraph 83 is reasonably understood as elaborating upon the compressible member 780 when formed of a substantially solid / compressible material in a contoured form 900, having a tapered leading edge 904, as shown in various forms in figs. 9A-9J.
Notably, paragraphs 81-83, do not mention the compressible member to be a “spring”.
In the next paragraph, paragraph 84, the possibility of the compressible member being a spring is introduced (i.e., the spring 1000 shown in figs. 10A-B), but this is prefaced with “In an alternative embodiment”. Paragraph 88 later elaborates that the compressible member can be any type of compressible member, including a variable rate spring, coil spring, washer or disc spring, etc., but no mention is made again of the fluid channels as recited for the substantially solid / compressible material.
As a result, while specification provides support for embodiments having at least one fluid channel defined in one or more of the compressible member, the stop, and the piston, when the compressible member is provided as a substantially solid / compressible material having a contoured form (i.e., as shown in figs. 9A-9J), the specification as originally filed would not be seen as reasonably conveying to one skilled in the art that the inventor had possession of embodiments having at least one fluid channel defined in one or more of the compressible member, the stop, and the piston, when the compressible member is provided as a spring, including a variable rate spring or a disc spring.
As a result, claims 8, 11, 16 & 19 contain subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor, at the time the application was filed, had possession of the claimed invention.
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.
Claim 24 is 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.
Claim 24 recites “wherein the compressible member…comprises a tapered leading edge configured to dampen movement of the second piston towards the stop…as the second piston becomes closer to the stop”, however, “the second piston” lacks proper antecedent basis in the claim . Claim 24 depends from claim 13 which recites only “a piston”, the compressible member coupled to “the piston”. Claim 1 recites both first and second pistons but, as noted, claim 24 does not depend from claim 1.
Double Patenting
The nonstatutory double patenting rejection is based on a judicially created doctrine grounded in public policy (a policy reflected in the statute) so as to prevent the unjustified or improper timewise extension of the “right to exclude” granted by a patent and to prevent possible harassment by multiple assignees. A nonstatutory double patenting rejection is appropriate where the conflicting claims are not identical, but at least one examined application claim is not patentably distinct from the reference claim(s) because the examined application claim is either anticipated by, or would have been obvious over, the reference claim(s). See, e.g., In re Berg, 140 F.3d 1428, 46 USPQ2d 1226 (Fed. Cir. 1998); In re Goodman, 11 F.3d 1046, 29 USPQ2d 2010 (Fed. Cir. 1993); In re Longi, 759 F.2d 887, 225 USPQ 645 (Fed. Cir. 1985); In re Van Ornum, 686 F.2d 937, 214 USPQ 761 (CCPA 1982); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Thorington, 418 F.2d 528, 163 USPQ 644 (CCPA 1969).
A timely filed terminal disclaimer in compliance with 37 CFR 1.321(c) or 1.321(d) may be used to overcome an actual or provisional rejection based on nonstatutory double patenting provided the reference application or patent either is shown to be commonly owned with the examined application, or claims an invention made as a result of activities undertaken within the scope of a joint research agreement. See MPEP § 717.02 for applications subject to examination under the first inventor to file provisions of the AIA as explained in MPEP § 2159. See MPEP § 2146 et seq. for applications not subject to examination under the first inventor to file provisions of the AIA . A terminal disclaimer must be signed in compliance with 37 CFR 1.321(b).
The filing of a terminal disclaimer by itself is not a complete reply to a nonstatutory double patenting (NSDP) rejection. A complete reply requires that the terminal disclaimer be accompanied by a reply requesting reconsideration of the prior Office action. Even where the NSDP rejection is provisional the reply must be complete. See MPEP § 804, subsection I.B.1. For a reply to a non-final Office action, see 37 CFR 1.111(a). For a reply to final Office action, see 37 CFR 1.113(c). A request for reconsideration while not provided for in 37 CFR 1.113(c) may be filed after final for consideration. See MPEP §§ 706.07(e) and 714.13.
The USPTO Internet website contains terminal disclaimer forms which may be used. Please visit www.uspto.gov/patent/patents-forms. The actual filing date of the application in which the form is filed determines what form (e.g., PTO/SB/25, PTO/SB/26, PTO/AIA /25, or PTO/AIA /26) should be used. A web-based eTerminal Disclaimer may be filled out completely online using web-screens. An eTerminal Disclaimer that meets all requirements is auto-processed and approved immediately upon submission. For more information about eTerminal Disclaimers, refer to www.uspto.gov/patents/apply/applying-online/eterminal-disclaimer.
Claims 1-8, 11-16, 19 & 21-24 are rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1 & 2 of U.S. Patent No. 12,031,556 (hereafter ‘556) in view of Nakamura et al. (JP 2006-220252 A; cited in applicant’s IDS received 08/11/2023; hereafter Nakamura), Wright (US 3,913,460), Perrott (US 4,926,897), and/or Bachler et al. (US 4,642,995; hereafter Bachler), as respectively set forth below.
Regarding instant claim 1, claim 1 of ‘556 recites (i.e., substantially verbatim) all of the limitations of claim 1 except the limitations of a compressible member positioned between the second piston and a stop; wherein the compressible member is configured to dampen motion of the second piston towards the stop, and wherein at least one fluid channel is defined in one or more of the compressible member, the stop, and the second piston, the at least one fluid channel configured to ensure oil is not isolated in a radially outer side of the compressible member.
Similarly, regarding instant claim 13, claim 1 of ‘556 anticipates or otherwise discloses all of the limitations of claim 13 except the limitations of a compressible member coupled to the piston and configured to contact a stop; wherein, as the piston approaches the stop, the compressible member dampens the movement of the piston, and wherein at least one fluid channel is defined in one or more of the compressible member, the stop, and the second piston, the at least one fluid channel configured to ensure oil is not isolated in a radially outer side of the compressible member.
However, such limitations not recited by claim 1 of ‘556 are rendered obvious at least in view of Wright (which teaches a compressible bumper member having a plurality of fluid channels at a tapered edge) and/or Bachler (which teaches compressible member between a piston and a stop in the form of various springs, including a coil and a disc spring with fluid channels), in each case, for damping motion / movement of the piston towards the stop and providing at least one fluid channel configured to ensure oil is not isolated in a radially outer side (see detailed discussion of these references in the grounds of rejection under 35 U.S.C. 103 in this action).
The limitations of instant claims 2, 4 & 12 are further rendered obvious in view of the teachings of Wright (i.e., wherein the piston has a ring shaped channel defined in the second piston, the compressible member at least partially positioned within the channel, and positioned around an orifice of the chamber when the comprisable member contacts the stop), while the limitation of instant claim 5 is rendered obvious in view of the combined teachings of Wright and Perrott (which teaches the use of a friction fit to secure a compressible member in a channel of a piston facing a stop).
Regarding instant claim 3, claim 1 of ‘556 further recites that the second gas chamber is defined in a housing and, if not already obvious from Wright and/or Bachler, the limitation wherein the stop is formed from the housing is otherwise obvious in view of Nakamura, which teaches a dual-piston accumulator having first and second pistons with a stop formed from the housing in a region between the pistons.
Regarding instant claim 6, claim 2 of ‘556 recites the limitations therein substantially verbatim.
Regarding instant claim 7, the limitation therein is further rendered obvious in view of Nakamura, which teaches that one of the gas chambers is a “high pressure” chamber while the other is a “low pressure” chamber, so as to provide a dual-stage functionality.
The limitations of instant claims 8, 11, 16 & 19 are each rendered obvious at least in view of Bachler (i.e., at least the conical coil springs in figs 4 & 5 being variable rate springs; figs. 6 & 7 teachings disc springs with channels, etc.).
The limitations of instant claims 14-15 are further rendered obvious in view of Nakamura, which, as noted for claim 3 above, teaches a stop formed in the housing and further teaches that an oil chamber of such an accumulator may be fluidly coupled to a hydraulic cylinder assembly (e.g., for damping the pressure fluctuations of the system under load, etc.).
The limitations of instant claims 21-24 are further rendered obvious in view of Wright, which teaches a compressible member formed from a substantially solid compressible material, comprising a tapered leading edge configured to dampen movement of the second piston towards the stop with greater force as the piston becomes closer to the stop, wherein the at least one fluid channel is defined through the tapered leading edge.
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.
Claims 1-4, 6-8, 12-16 & 20-24 are rejected under 35 U.S.C. 103 as being unpatentable over Nakamura et al. (JP 2006-220252 A; hereafter Nakamura) in view of Wright (US 3,913,460).
Examination Note: references to the specification of Nakamura refer to the corresponding English translation filed by applicant on 08/11/2023.
Regarding claim 1, Nakamura discloses (i.e., figs. 1-3) an accumulator (1), comprising:
an oil chamber (11, 12, 13);
a first piston (5) separating a first gas chamber (18) from the oil chamber; and
a second piston (3) separating a second gas chamber (17) from the oil chamber;
wherein a stop (21) for the second piston is formed in a housing (6-10).
Nakamura does not explicitly disclose a compressible member positioned between the second piston and the stop, wherein the compressible member is configured to dampen motion of the second piston towards the stop.
Nakamura also discloses (in alternative embodiments shown in figs. 3b, 4a&b, 5a&b, etc.) at least one fluid channel (24 and/or 27) defined in one or more of the stop (i.e. 24 formed within the stop) and the second piston (i.e., 27 formed in the piston) configured to provide at least some communication between the oil chamber and a radially outer side of a feature of the second piston. However, Nakamura does not explicitly disclose such a fluid channel configured to ensure oil is not isolated in a radially outer side of a compressible member.
Wright teaches (figs. 1-5 & 10-12) a device comprising a housing (12, 14, 16) having a piston (18) separating a first fluid chamber (communicating with port 24) from a second fluid chamber (communicating with port 22), and a compressible member (28; “combination seal and impact damping means in the form of bumper rings”,”…formed or molded of resilient rubber-like material…”) positioned between the piston (18) and a stop (42; “inner face of a cylinder head”); wherein the compressible member (28) is configured to dampen motion of the piston towards the stop (see fig. 2; col. 2, line 65 – col. 3, line 2; col. 3, lines 24-35).
Wright further teaches that at least one fluid channel (52, 56) may be defined in one or more of the compressible member and the stop, the at least one fluid channel configured to ensure oil is not isolated in a radially outer side of the compressible member.
In particular, a first arrangement shown in figs. 1 & 2 includes at least one fluid channel 52 (“bleed hole”) to “relieve fluid that may be trapped during cushioning” (col. 3, lines 37-43).
In a modified form of the compressible member (28) shown in figs. 5 & 12, Wright teaches that the compressible member may comprise a tapered leading edge (at 40), and a plurality of fluid channels (56)(“relief ports”) may be defined in the tapered leading edge to “prevent excess pressure build-up… during impact, and will serve also as vacuum break during piston breakaway, precluding the possibility of displacement of the ring from the piston groove” (col. 3, line 60 – col. 4, line 2; see also col. 1, lines 45-50).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to modify the accumulator of Nakamura to further comprise a compressible member (i.e., a compressible, impact damping bumper ring formed from resilient rubber-like material) positioned between the second piston and the stop (i.e., at least partially disposed in an annular groove/recess of the second piston on a side facing the stop), wherein the compressible member is configured to dampen motion of the second piston towards the stop (i.e., by contacting the stop before the piston and compressing), in view of the teachings of Wright, so as to soften the effect of the impact of the piston against the stop (as is already generally known for reciprocating piston devices, as suggested by the prior art section of Wright) and/or to provide such a piston cushioning/damping mechanism which does not necessarily rely upon the working fluid to provide the dampening effect (i.e., as would a conventional flow-restriction type cushioning arrangement), ensuring that the piston does not harshly impact the stop even in the event that the working fluid is not present or otherwise insufficient (e.g., during initial charging, or in the event of leakage / air entrainment, etc.).
It would have been further obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to modify the accumulator of Nakamura to include at least one fluid channel defined in one or more of the compressible member, the stop, and the second piston (e.g., a fluid channel / bleed hole in the stop and/or a plurality of relief ports defined in a tapered leading edge of the compressible member), the at least one fluid channel configured to ensure oil is not isolated in a radially outer side of the compressible member, in view of the teachings of Wright, to relieve fluid that may be trapped during damping, preventing excess pressure build-up between the stop and the outer side of the compressible member during impact and serving as a vacuum break on a reverse stroke of the piston, as suggested by Wright.
Regarding claim 2, the accumulator of Nakamura, as modified above, reads on the additional limitation wherein the second piston has a channel defined therein (i.e., corresponding to the piston grooves 34 / annular mounting grooves 39 of Wright) and the compressible member (i.e., corresponding to 28 of Wright) is at least partially positioned within the channel (i.e., as shown by Wright, at least a portion of a flange 32 of the compressible member is positioned within the channel / groove).
Regarding claim 3, the accumulator of Nakamura, as modified above, reads on the additional limitation wherein the second gas chamber (17) is defined in a housing (incl. 6, 7, 8, 9, 10) and the stop (21) is formed from the housing (i.e., stop 21 formed from at least component 6 of the housing, as shown).
Regarding claim 4, the accumulator of Nakamura, as modified above, reads on the additional limitation wherein the channel (i.e., corresponding to the annular groove 34 / 39 of Wright) is defined in a ring about an axis that extends through the second piston (i.e., as shown from figs. 1 & 2 of Wright, the annular groove / channel 34 / 39 is reasonably depicted as a ring defined about an axis that extends through the piston 18; whereby when the accumulator of Nakamura is modified in view of Wright as set forth above, the channel in the second piston would reasonably be configured in a corresponding manner).
Regarding claims 6 & 7, the accumulator of Nakamura, as modified above, reads on the additional limitations wherein the first gas chamber (18) is configured to provide a first pre-charge pressure (i.e., a “low pressure”; e.g., 2.5 MPa) and the second gas chamber (17) is configured to provide a second pre-charge pressure (i.e., a “high pressure”; e.g., 5 MPa), the second pre-charge pressure being different than the first pre-charge pressure (as in claim 6), wherein the accumulator is configured to have the second pre-charge pressure (e.g., 5MPa, as the “high pressure accumulator”) be greater than the first pre-charge pressure (e.g., 2.5 MPa, as the “low pressure accumulator”; see paras. 5, 11, 32-35, etc.)(as in claim 7).
Regarding claim 8, with respect to the limitation wherein the compressible member comprises a spring having a variable spring rate, it is noted that one common and accepted definition of “spring” is “an elastic mechanical part or device in any shape (e.g., flat, curved, coiled), made of flexible material that exerts force and attempts to spring back when bent, compressed, or stretched”.
In view of the above, the annular compressible member of Wright, formed from a resilient rubber-like material and having a tapered leading edge (i.e., as utilized in the accumulator of Nakamura, above) is reasonably seen as comprising a spring.
Additionally, unlike (for example) a conventional coil spring, an annular compressible member of the type taught by Wright, having a tapered leading edge, would reasonably be expected to have a variable spring rate (that is, the force required to compress the member would increase non-linearly).
Regarding claim 12, the accumulator of Nakamura, as modified above, would read on the additional limitation wherein the compressible member (i.e., 28 of Wright) is positioned around an orifice of the oil chamber (i.e., 13A and/or 20 of Nakamura; corresponding to the central orifice in end wall 14 of Wright, communicating with port 22) when the compressible member contacts the stop (i.e., 21 of Nakamura; corresponding to 42 of Wright, see fig. 2 of Wright).
Regarding claim 13, Nakamura discloses (i.e., figs. 1-3) an accumulator (1), comprising:
a housing (6-10) defining a gas chamber (e.g., 17) and an oil chamber (11, 12, 13);
a piston (e.g., 3) positioned between the gas chamber and the oil chamber and configured to selectively slide within the housing (see figs. 1-3);
wherein a stop (21) for the piston is formed in the housing.
Nakamura does not explicitly disclose a compressible member coupled to the piston and configured to contact the stop; wherein, as the piston approaches the stop, the compressible member dampens the movement of the piston.
Nakamura also discloses (in alternative embodiments shown in figs. 3b, 4a&b, 5a&b, etc.) at least one fluid channel (24 and/or 27) defined in one or more of the stop (i.e. 24 formed within the stop) and the piston (i.e., 27 formed in the piston) configured to provide at least some communication between the oil chamber and a radially outer side of a feature of the piston. However, Nakamura does not explicitly disclose such a fluid channel configured to ensure oil is not isolated in a radially outer side of a compressible member.
Wright teaches (figs. 1-5 & 10-12) a device comprising a housing (12, 14, 16) having a piston (18) separating a first fluid chamber (communicating with port 24) from a second fluid chamber (communicating with port 22), and a compressible member (28; “combination seal and impact damping means in the form of bumper rings”,”…formed or molded of resilient rubber-like material…”) coupled to the piston (18) and configured to contact a stop (42; “inner face of a cylinder head”); wherein, as the piston approaches the stop, the compressible member (28) dampens the movement of the piston (see fig. 2; col. 2, line 65 – col. 3, line 2; col. 3, lines 24-35).
Wright further teaches that at least one fluid channel (52, 56) may be defined in one or more of the compressible member and the stop, the at least one fluid channel configured to ensure oil is not isolated in a radially outer side of the compressible member.
In particular, a first arrangement shown in figs. 1 & 2 includes at least one fluid channel 52 (“bleed hole”) to “relieve fluid that may be trapped during cushioning” (col. 3, lines 37-43).
In a modified form of the compressible member (28) shown in figs. 5 & 12, Wright teaches that the compressible member may comprise a tapered leading edge (at 40), and a plurality of fluid channels (56)(“relief ports”) may be defined in the tapered leading edge to “prevent excess pressure build-up… during impact, and will serve also as vacuum break during piston breakaway, precluding the possibility of displacement of the ring from the piston groove” (col. 3, line 60 – col. 4, line 2; see also col. 1, lines 45-50).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to modify the accumulator of Nakamura to further comprise a compressible member (i.e., a compressible, impact damping bumper ring formed from resilient rubber-like material) coupled to the piston (e.g., via an annular groove/recess of the piston on a side facing the stop) and configured to contact the stop, wherein, as the piston approaches the stop, the compressible member dampens the movement of the piston (i.e., by contacting the stop before the piston and compressing), in view of the teachings of Wright, so as to soften the effect of the impact of the piston against the stop (as is already generally known for reciprocating piston devices, as suggested by the prior art section of Wright) and/or to provide such a piston cushioning/damping mechanism which does not necessarily rely upon the working fluid to provide the dampening effect (i.e., as would a conventional flow-restriction type cushioning arrangement), ensuring that the piston does not harshly impact the stop even in the event that the working fluid is not present or otherwise insufficient (e.g., during initial charging, or in the event of leakage / air entrainment, etc.).
It would have been further obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to modify the accumulator of Nakamura to include at least one fluid channel defined in one or more of the compressible member, the stop, and the piston (e.g., a fluid channel / bleed hole in the stop and/or a plurality of relief ports defined in a tapered leading edge of the compressible member), the at least one fluid channel configured to ensure oil is not isolated in a radially outer side of the compressible member, in view of the teachings of Wright, to relieve fluid that may be trapped during damping, preventing excess pressure build-up between the stop and the outer side of the compressible member during impact and serving as a vacuum break on a reverse stroke of the piston, as suggested by Wright.
Regarding claim 14, the accumulator of Nakamura reads on the additional limitation wherein the stop (21) is formed in the housing (i.e., stop 21 formed from at least component 6 in housing, as shown).
Regarding claim 15, Nakamura discloses or otherwise reasonably suggests the additional limitation wherein the oil chamber (11, 12, 13) is fluidly coupled to a hydraulic cylinder assembly (see, e.g., paras. 2 & 28; published claim 1, etc.).
In particular, Nakamura explains (e.g., in para. 28) that the accumulator is connected to a hydraulic circuit (not shown) via component 6. In paragraph 2, Nakamura explains that, in such hydraulic circuits (systems), “actuators such as hydraulic motors and hydraulic cylinders” are supplied by hydraulic oil from a pump and, when a large load is applied to the actuators or when the actuators are locked, hydraulic pressure in the system can increase. By providing an accumulator in the system, the accumulator can absorb the additional pressure, relieve the load on the actuators, and can otherwise provide pressure regulation for such a hydraulic system.
Thus, Nakamura reasonably discloses that the oil chamber may be fluidly coupled to a hydraulic cylinder assembly (i.e., as may be present in the hydraulic circuit).
Regarding claim 16, with respect to the limitation wherein the compressible member comprises a spring having a variable spring rate, it is noted that one common and accepted definition of “spring” is “an elastic mechanical part or device in any shape (e.g., flat, curved, coiled), made of flexible material that exerts force and attempts to spring back when bent, compressed, or stretched”.
In view of the above, the annular compressible member of Wright, formed from a resilient rubber-like material and having a tapered leading edge (i.e., as utilized in the accumulator of Nakamura, above) is reasonably seen as comprising a spring.
Additionally, unlike (for example) a conventional coil spring, an annular compressible member of the type taught by Wright, having a tapered leading edge, would reasonably be expected to have a variable spring rate (that is, the force required to compress the member would increase non-linearly).
Regarding claim 20, the combination of Nakamura and Wright, as set forth in the grounds of rejection for claims 1 and/or 13 above, renders obvious a method of assembling an accumulator (i.e., the accumulator of Nakamura, as modified in view of Wright to include a compressible member and at least one fluid channel, etc.), comprising:
coupling a compressible member (i.e., corresponding to 28 of Wright) to a piston (e.g., piston 3 of Nakamura, corresponding to piston 18 of Wright; as by placing the compressible member in a piston groove provided for that purpose; see Wright, col. 2, lines 37-60); and
positioning the piston in a housing (6-10 of Nakamura; corresponding to 12, 14, 16 of Wright) to selectively slide along an accumulator axis such that the compressible member is positioned between the piston and a stop (21 of Nakamura; corresponding to 42 of Wright; see fig. 2 of Wright), the piston fluidly separating an oil chamber (11, 12, 13 of Nakamura) from a gas chamber (17 of Nakamura);
wherein the compressible member is configured to selectively dampen the motion of the piston towards the stop (i.e., by contacting the stop before the piston and compressing);
wherein at least one fluid channel is defined in one or more of the compressible member, the stop, and the piston (e.g., a fluid channel / bleed hole in the stop and/or a plurality of relief ports defined in a tapered leading edge of the compressible member; each as taught by Wright), the at least one fluid channel configured to ensure oil is not isolated in a radially outer side of the compressible member (i.e., to relieve fluid that may be trapped during damping, preventing excess pressure build-up between the stop and the outer side of the compressible member during impact and serving as a vacuum break on a reverse stroke of the piston, as suggested by Wright).
Regarding claims 21-24, the accumulator of Nakamura, as modified in view of Wright in the grounds of the rejection for claims 1 & 13 above, reads on or otherwise renders obvious the additional limitations wherein the compressible member (i.e., corresponding to 28 of Wright) comprises a tapered leading edge (see tapered edge at 40 in figs. 1, 5, 12, etc. of Wright) configured to dampen the movement of the second piston towards the stop with greater force as the second piston becomes closer to the stop (see Wright, col. 3, lines 2-9: “In a preferred construction, the bumper has an interior annular wall 44…, which is inclined relative to an external annular wall 46, resulting in a reduction of material at the crest of the bumper. This produces a progressively increasing resistance to impact in the body of the bumper, from the crest thereof to the bumper base”)(claims 21 & 24), wherein the at least one fluid channel (56 of Wright) is defined through the tapered leading edge (see figs. 5 & 12 of Wright)(claims 22 & 24), and wherein the compressible member is formed of a substantially solid compressible material (Wright, col. 2, lines 57-60: “Ring 28 is formed or molded of resilient rubber-like material, and it may therefore be stretched and distorted as required…”; see also col. 2, line 64 – col. 3, line 9)(claims 23 & 24).
Claims 1-8, 11-16 & 19 are rejected under 35 U.S.C. 103 as being unpatentable over Nakamura in view of Bachler et al. (US 4,642,995; hereafter Bachler).
Regarding claim 1, Nakamura discloses (i.e., figs. 1-3) an accumulator (1), comprising:
an oil chamber (11, 12, 13);
a first piston (5) separating a first gas chamber (18) from the oil chamber; and
a second piston (3) separating a second gas chamber (17) from the oil chamber;
wherein a stop (21) for the second piston is formed in a housing (6-10).
Nakamura does not explicitly disclose a compressible member positioned between the second piston and the stop, wherein the compressible member is configured to dampen motion of the second piston towards the stop.
Nakamura also discloses (in alternative embodiments shown in figs. 3b, 4a&b, 5a&b, etc.) at least one fluid channel (24 and/or 27) defined in one or more of the stop (i.e. 24 formed within the stop) and the second piston (i.e., 27 formed in the piston) configured to provide at least some communication between the oil chamber and a radially outer side of a feature of the second piston. However, Nakamura does not explicitly disclose such a fluid channel configured to ensure oil is not isolated in a radially outer side of a compressible member.
Bachler teaches (various embodiments in figs. 1-14) an arrangement comprising a piston (2, 2a, 2b, etc.; “displacer”) configured to reciprocate within a cylindrical bore (43) of a housing (31)(see fig. 14), wherein the housing forms a stop / end wall (45) at one end, with a working chamber (46) positioned between the piston (2) and the stop / end wall (45).
Bachler further teaches positioning a compressible member between the piston and the stop, wherein the compressible member is configured to dampen motion of the piston towards the stop (i.e., the compressible member is “compressed as the displacer approaches the substantially closed end of the hollow space to damp the vibration and noise which otherwise could be produced by contact between the substantially-closed end of the hollow space and the displacer” [col. 2, lines 25-35]).
Bachler teaches various embodiments of such compressible members in figs. 1-14 (e.g., conical coil springs 8, 9 [“conical, coil springs”] in figs. 4 & 5; disc spring 12 having radial channels [“sheet metal radial spring 12…like a disc spring, but having radial slots…”]).
With respect to the limitation wherein at least one fluid channel is defined in one or more of the compressible member, the stop, and the piston, the at least one fluid channel configured to ensure oil is not isolated in a radially outer side of the compressible member, it is noted that at least the conical coil springs 8, 9 (in figs. 4 & 5) and the disc spring 12 (in figs. 6 & 7), are reasonably seen as including at least one fluid channel which would prevent oil from being isolated in a radially outer side of the compressible member (i.e., for the conical springs 8, 9, the spaces between adjacent coils would reasonably provide a fluid channel for the oil to pass through; for the disc spring 12, the “radial slots” between tongues 13 would clearly serve as fluid channels defined in the compressible member which would ensure oil is not isolated in a radially outer side of the compressible member).
Finally, Bachler explains that the use of such compressible member arrangements can serve to minimize “dead space” between the piston and the stop (i.e., relative to conventional coil springs; e.g., col. 1, lines 51-64 & col. 2, lines 5-10) while enabling a simpler design than those which may utilize “trapped fluid” for cushioning (e.g., col. 1, line 65 – col. 2, line 10, etc.).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to modify the accumulator of Nakamura to further comprise a compressible member (e.g., a disc spring with radial slots, a conical coil spring, etc.) positioned between the second piston and the stop; wherein the compressible member is configured to dampen motion of the second piston towards the stop, wherein at least one fluid channel is defined in one or more of the compressible member, the stop, and the second piston, the at least one fluid channel configured to ensure oil is not isolated in a radially outer side of the compressible member (i.e., the fluid channel defined by the gaps between the coils of the conical coil springs, or the plurality of radial slots in the disc spring), in view of the teachings of Bachler, to reduce vibration and noise which may otherwise occur when the piston contacts the stop, while minimizing dead space, and with a simpler design than may be required for a trapped fluid-type arrangement (i.e., as suggested by Bachler).
Regarding claims 2, 4 & 5, with respect to the limitations wherein the second piston has a channel defined therein and the compressible member is at least partially positioned within the channel (claim 2), wherein the channel is defined in a ring about an axis that extends through the second piston (claim 4), and wherein the channel is sized to correspond with the compressible member to retain at least a portion of the compressible member therein through a friction fit (claim 5), it is noted that, in at least the embodiments taught by Bachler in figs. 5 & 6, the piston comprises a reduced-diameter projecting section (e.g., 6a’ in fig. 5). As can be seen, this results in an annular (i.e. ring-shaped) channel defined in the end of the piston about an axis that extends through the piston, wherein the channel is sized to correspond to the compressible member to retain at least a portion of the compressible member therein.
Further, when describing a disc spring arrangement (4) of fig. 2 (similar to the disc spring 12 shown in figs. 6-7), Bachler teaches that the disc spring is attached to a reduced-diameter projecting section 6a “by force fit” (col. 3, lines 26-29)(i.e., by a friction fit, as best understood).
If not already seen as such, when modifying the accumulator of Nakamura to comprise a compressible member in view of Bachler, it would have been further obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to modify the accumulator such that the second piston has a channel defined therein and the compressible member is at least partially positioned within the channel (as in claim 2), wherein the channel is defined in a ring about an axis that extends through the second piston (as in claim 4), and wherein the channel is sized to correspond with the compressible member to retain at least a portion of the compressible member therein through a friction fit (as in claim 5), in view of the teachings of Bachler, to provide a simple method of coupling the compressible member to the piston without any additional fastening components (i.e., via such a friction fit) while minimizing dead space between the piston face and the stop (i.e., via partially recessing the compressible member into the channel, etc.).
Regarding claim 3, the accumulator of Nakamura, as modified above, reads on the additional limitation wherein the second gas chamber (17) is defined in a housing (incl. 6, 7, 8, 9, 10) and the stop (21) is formed from the housing (i.e., stop 21 formed from at least component 6 of the housing, as shown).
Regarding claims 6 & 7, the accumulator of Nakamura, as modified above, reads on the additional limitations wherein the first gas chamber (18) is configured to provide a first pre-charge pressure (i.e., a “low pressure”; e.g., 2.5 MPa) and the second gas chamber (17) is configured to provide a second pre-charge pressure (i.e., a “high pressure”; e.g., 5 MPa), the second pre-charge pressure being different than the first pre-charge pressure (as in claim 6), wherein the accumulator is configured to have the second pre-charge pressure (e.g., 5MPa, as the “high pressure accumulator”) be greater than the first pre-charge pressure (e.g., 2.5 MPa, as the “low pressure accumulator”; see paras. 5, 11, 32-35, etc.)(as in claim 7).
Regarding claim 8, the accumulator of Nakamura, at least when modified in view of Bachler to include a compressible member in the form of a conical coil spring (i.e., as in figs. 4 & 5), reads on the additional limitation wherein the compressible member comprises a spring having a variable spring rate.
In particular, such coiled conical springs, at least when comprising a consistent wire diameter as reasonably shown in figs. 4 & 5, exhibit variable spring rates, as the larger coil diameter portions exhibit relatively lower spring rates, and the smaller coil diameter portions exhibit relatively higher spring rates.
Regarding claim 11, the accumulator of Nakamura, when modified in view of Bachler to include a compressible member in the form of a disc spring having radial channels (e.g., disc spring 12 in figs. 6-7), reads on the additional limitation wherein the compressible member comprises a disc spring.
Regarding claim 12, in the accumulator of Nakamura, the piston is reasonably shown to be axially aligned with the center of a corresponding orifice (20 and/or 13A) of the oil chamber at the stop (21). Since the compressible members of Bachler are taught to be contacted with an end wall (rather than inserted into an orifice, for example), the accumulator of Nakamura, at least when modified in view of Bachler to comprise a compressible member of annular form concentric with the piston axis (i.e., as in figs. 4-6), would reasonably be configured such that the compressible member is positioned around the orifice of the oil chamber when the compressible member contacts a stop.
Regarding claim 13, Nakamura discloses (i.e., figs. 1-3) an accumulator (1), comprising:
a housing (6-10) defining a gas chamber (e.g., 17) and an oil chamber (11, 12, 13);
a piston (e.g., 3) positioned between the gas chamber and the oil chamber and configured to selectively slide within the housing (see figs. 1-3);
wherein a stop (21) for the piston is formed in the housing.
Nakamura does not explicitly disclose a compressible member coupled to the piston and configured to contact the stop; wherein, as the piston approaches the stop, the compressible member dampens the movement of the piston.
Nakamura also discloses (in alternative embodiments shown in figs. 3b, 4a&b, 5a&b, etc.) at least one fluid channel (24 and/or 27) defined in one or more of the stop (i.e. 24 formed within the stop) and the piston (i.e., 27 formed in the piston) configured to provide at least some communication between the oil chamber and a radially outer side of a feature of the piston. However, Nakamura does not explicitly disclose such a fluid channel configured to ensure oil is not isolated in a radially outer side of a compressible member.
Bachler teaches (various embodiments in figs. 1-14) an arrangement comprising a piston (2, 2a, 2b, etc.; “displacer”) configured to reciprocate within a cylindrical bore (43) of a housing (31)(see fig. 14), wherein the housing forms a stop / end wall (45) at one end, with a working chamber (46) positioned between the piston (2) and the stop / end wall (45).
Bachler further teaches a compressible member coupled to the piston and configured to contact the stop, wherein, as the piston approaches the stop, the compressible member dampens the movement of the piston (i.e., the compressible member is “compressed as the displacer approaches the substantially closed end of the hollow space to damp the vibration and noise which otherwise could be produced by contact between the substantially-closed end of the hollow space and the displacer” [col. 2, lines 25-35]).
Bachler teaches various embodiments of such compressible members in figs. 1-14 (e.g., conical coil springs 8, 9 [“conical, coil springs”] in figs. 4 & 5; disc spring 12 having radial channels [“sheet metal radial spring 12…like a disc spring, but having radial slots…”]).
With respect to the limitation wherein at least one fluid channel is defined in one or more of the compressible member, the stop, and the piston, the at least one fluid channel configured to ensure oil is not isolated in a radially outer side of the compressible member, it is noted that at least the conical coil springs 8, 9 (in figs. 4 & 5) and the disc spring 12 (in figs. 6 & 7), are reasonably seen as including at least one fluid channel which would prevent oil from being isolated in a radially outer side of the compressible member (i.e., for the conical springs 8, 9, the spaces between adjacent coils would reasonably provide a fluid channel for the oil to pass through; for the disc spring 12, the “radial slots” between tongues 13 would clearly serve as fluid channels defined in the compressible member which would ensure oil is not isolated in a radially outer side of the compressible member).
Finally, Bachler explains that the use of such compressible member arrangements can serve to minimize “dead space” between the piston and the stop (i.e., relative to conventional coil springs; e.g., col. 1, lines 51-64 & col. 2, lines 5-10) while enabling a simpler design than those which may utilize “trapped fluid” for cushioning (e.g., col. 1, line 65 – col. 2, line 10, etc.).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to modify the accumulator of Nakamura to further comprise a compressible member (e.g., a disc spring with radial slots, a conical coil spring, etc.) coupled to the piston and configured to contact the stop; wherein, when the piston approaches the stop, the compressible member dampens the movement of the piston, wherein at least one fluid channel is defined in one or more of the compressible member, the stop, and the piston, the at least one fluid channel configured to ensure oil is not isolated in a radially outer side of the compressible member (i.e., the fluid channel defined by the gaps between the coils of the conical coil springs, or the plurality of radial slots in the disc spring), in view of the teachings of Bachler, to reduce vibration and noise which may otherwise occur when the piston contacts the stop, while minimizing dead space, and with a simpler design than may be required for a trapped fluid-type arrangement (i.e., as suggested by Bachler).
Regarding claim 14, the accumulator of Nakamura reads on the additional limitation wherein the stop (21) is formed in the housing (i.e., stop 21 formed from at least component 6 in housing, as shown).
Regarding claim 15, Nakamura discloses or otherwise reasonably suggests the additional limitation wherein the oil chamber (11, 12, 13) is fluidly coupled to a hydraulic cylinder assembly (see, e.g., paras. 2 & 28; published claim 1, etc.).
In particular, Nakamura explains (e.g., in para. 28) that the accumulator is connected to a hydraulic circuit (not shown) via component 6. In paragraph 2, Nakamura explains that, in such hydraulic circuits (systems), “actuators such as hydraulic motors and hydraulic cylinders” are supplied by hydraulic oil from a pump and, when a large load is applied to the actuators or when the actuators are locked, hydraulic pressure in the system can increase. By providing an accumulator in the system, the accumulator can absorb the additional pressure, relieve the load on the actuators, and can otherwise provide pressure regulation for such a hydraulic system.
Thus, Nakamura reasonably discloses that the oil chamber may be fluidly coupled to a hydraulic cylinder assembly (i.e., as may be present in the hydraulic circuit).
Regarding claim 16, the accumulator of Nakamura, at least when modified in view of Bachler to include a compressible member in the form of a conical coil spring (i.e., as in figs. 4 & 5), reads on the additional limitation wherein the compressible member comprises a spring having a variable spring rate. In particular, such coiled conical springs, at least when comprising a consistent wire diameter as reasonably shown in figs. 4 & 5, exhibit variable spring rates, as the larger coil diameter portions exhibit relatively lower spring rates, and the smaller coil diameter portions exhibit relatively higher spring rates.
Regarding claim 19, the accumulator of Nakamura, when modified in view of Bachler to include a compressible member in the form of a disc spring having radial channels (e.g., disc spring 12 in figs. 6-7), reads on the additional limitation wherein the compressible member comprises a disc spring.
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Nakamura in view of Wright as applied to claim 2 above, and further in view of Klaus (US 3,329,068) and Perrott (US 4,926,897).
Regarding claim 5, the accumulator of Nakamura, as modified above, reads on the additional limitations wherein the channel (i.e. 34 / 39 of Wright) is sized to correspond with the compressible member to retain at least a portion of the compressible member therein (i.e. flange 32 of the compressible member being retained therein via a projecting annular flange 36 of the piston).
Nakamura and Wright do not explicitly disclose the additional limitation wherein the channel is sized to correspond with the compressible member to retain at least a portion of the compressible member therein through a friction fit.
Klaus teaches (figs. 1 & 2) a piston (24) comprising a compressible member (106; “annular bumper pad 106”) positioned between the piston (24) and a stop (the surface of end wall 32), the compressible member positioned within an “annular groove or recess 108” in the end face of the piston, wherein the compressible member (106) is configured to damped motion of the piston towards the stop.
Perrott similarly teaches (figs. 1-3) a piston (32) configured to reciprocate between two end stops (19, 31) having respective compressible members (48, 50) positioned between the piston and each end stop to dampen motion of the piston towards the stops, wherein each end of the piston is provided with a channel (47, 49) sized to correspond with the respective compressible member (48, 50) to retain at least a portion of the compressible member therein through a friction fit (col. 3, lines 36-39: “[t]hese receive in a friction fit longitudinally perforated compressible pads or sleeves 48, 50 respectively which serve as bumpers at the extreme limit of piston stroke in each direction”).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to modify the accumulator of Nakamura, as otherwise modified above, such that the channel is sized to correspond with the compressible member to retain at least a portion of the compressible member therein through a friction fit, in view of the teachings of Klaus and Perrott (i.e., by replacing the original attachment arrangement of Wright, requiring a reduced diameter portion projecting from the piston end, terminating in a projecting annular flange to create a radially-outward facing retaining groove; with a simplified arrangement wherein the annular compressible member is positioned within a simple axially-facing annular channel recessed in the end face of the piston and retained therein by friction fit), which may enable simplification of the piston design / manufacture and may otherwise enable a reduction in the axial length of the piston to produce a more compact assembly (i.e., by eliminating the projecting reduced-diameter and flange portions previously required to form the channel and instead recessing a connecting portion of the compressible member a channel formed directly in the end face of the piston, etc.).
Examination Note: to promote compact prosecution, see also US 4,461,322 to Mills, figures 7 & 8 (showing an annular seal fitted into a simple ring-shaped groove) vs figures 5 & 6 (showing an annular seal retained by a fastener). Mills explains that the embodiment of figs. 5-6 is more secure but the embodiment of figs. 7-8 is cheaper and easier to manufacture (col. 4, lines 23-32).
Response to Arguments
Applicant's arguments filed 23 December 2025 have been fully considered.
Regarding the 35 U.S.C. § 102 rejections in view of Mills and the 35 U.S.C. § 103 rejections in view of Nakamura and Klaus, applicant’s amendments to the claims have overcome these rejections. However, new grounds of rejection have been applied to the amended claims in this action, as necessitated by applicant’s amendments.
Regarding applicant’s arguments directed to the 35 U.S.C. § 103 rejections in view of Nakamura and Bachler, it is noted that several of the embodiments taught by Bachler appear to include compressible members in the form of springs having features which may reasonably be seen as fluid channels configured to ensure fluid is not isolated in a radially outer side of the compressible member. The grounds of rejection in this action have been amended accordingly, as necessitated by applicant’s amendment. It is also noted that applicant’s specification does not appear to provide sufficient support for embodiments wherein the compressible member is a spring (as in figs. 10a-b) as opposed to a solid compressible member (as in figs. 9a-9j), though such a combination is now claimed (see related 35 U.S.C. 112(a) rejections in this action).
Conclusion
The prior art made of record in the attached PTO-892 and not relied upon is considered pertinent to applicant's disclosure.
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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.
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/Richard K. Durden/Examiner, Art Unit 3753
/KENNETH RINEHART/Supervisory Patent Examiner, Art Unit 3753