DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application on 17 June 2026 after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 14 May 2026 has been entered.
Response to Amendment
This office action is responsive to the amendment filed on 14 May 2026, entered pursuant to the request for continued examination filed on 17 June 2026. As directed by the amendment: claims 1, 3, 13, 20, 23 & 24 have been amended, claims 15 & 22 have been cancelled, and claims 25 & 26 have been added. Claims 9, 10, 17 & 18 were cancelled by previous amendments. Thus, claims 1-8, 11-14, 16, 19-21 & 23-26 are presently pending in this application.
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, 11-14, 16, 19, 21 & 23-26 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.
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.
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 (see detailed discussion of these references, and corresponding motivations for combining, 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, 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, 25 & 26 are each rendered obvious at least in view of Bachler (i.e., at least the springs in figs 4 & 5 being variable rate springs and coil springs; figs. 6 & 7 teachings disc springs with channels, etc.).
The limitations of instant claim 14 are further rendered obvious in view of Nakamura, which, as noted for claim 3 above, teaches a stop formed in the housing.
The limitations of instant claims 21, 23 & 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.
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, 12-14, 16 & 20, 21, 23 & 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 Theobald et al. (US 8,567,185; hereafter Theobald) and 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;
a fluid passage (13C) configured to fluidly couple the oil chamber to a hydraulic cylinder assembly (see, e.g., paras. 2 & 28; published claim 1, etc.);
wherein a stop (21) for the second piston is formed in a housing (6-10);
wherein the first gas chamber (18), second gas chamber (17), oil chamber (11-13), and fluid passage (13C) are defined within the housing (incl. 6-10);
wherein, the first and second piston are independently movable to alter the volume of the oil chamber (i.e., see figs. 1-3; each piston is independently movable, based on the relative pressure difference between the oil chamber pressure and respective pressures in the first and second gas chambers).
Nakamura does not explicitly disclose a hydraulic borehole configured to at least partially receive a hydraulic cylinder assembly, the fluid passage fluidly coupling the oil chamber to the hydraulic borehole, wherein the hydraulic borehole is defined within the housing; or 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.
Theobald teaches (fig. 2) a hydraulic assembly (12) comprising an oil chamber (i.e. the chamber of either accumulator 16a or 16b which is in communication with hydraulic borehole 26 as shown), an accumulator piston (36) separating the oil chamber from an opposing biasing chamber (i.e., the chambers having springs as shown, but Theobald suggests that other accumulator designs can be used), a hydraulic borehole (26) configured to at least partially receive a hydraulic cylinder assembly (24, 30), a fluid passage fluidly coupling the oil chamber of the accumulator to the hydraulic borehole (as shown), wherein the accumulator biasing chamber, accumulator oil chamber, hydraulic borehole, and fluid passage are each defined within a housing (as shown).
Theobald explains that this assembly is “designed as a single component” having the various subcomponents, including the accumulators “integrally formed with the actuator 12 as one member” (col. 3, lines 64-68).
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 including a hydraulic borehole within the housing, the hydraulic borehole configured to at least partially receive a hydraulic cylinder assembly, wherein the fluid passage fluidly couples the oil chamber to the hydraulic borehole, in view of the teachings of Theobald, to provide an integrated, single component hydraulic actuator system which improves efficiency by, for example, avoiding the need to interconnect the subcomponents of such a hydraulic system by separate small diameter hydraulic lines (as suggested by Theobald).
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).
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.).
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 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), an oil chamber (11, 12, 13), and a fluid passage (13C) configured to fluidly couple the oil chamber to a hydraulic cylinder assembly (see, e.g., paras. 2 & 28; published claim 1, etc.); and
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 the housing to define a hydraulic borehole, the fluid passage fluidly coupling the oil chamber to the hydraulic borehole, and further does not disclose a hydraulic cylinder assembly configured to be at least partially received within the hydraulic borehole; or 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.
Theobald teaches (fig. 2) a hydraulic assembly (12) comprising an oil chamber (i.e. the chamber of either accumulator 16a or 16b which is in communication with hydraulic borehole 26 as shown), an accumulator piston (36) separating the oil chamber from an opposing biasing chamber (i.e., the chambers having springs as shown, but Theobald suggests that other accumulator designs can be used), a hydraulic borehole (26) configured to at least partially receive a hydraulic cylinder assembly (24, 30), a fluid passage fluidly coupling the oil chamber of the accumulator to the hydraulic borehole (as shown), wherein the accumulator biasing chamber, accumulator oil chamber, hydraulic borehole, and fluid passage are each defined within a housing (as shown).
Theobald explains that this assembly is “designed as a single component” having the various subcomponents, including the accumulators “integrally formed with the actuator 12 as one member” (col. 3, lines 64-68).
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 including a hydraulic borehole within the housing, wherein the fluid passage fluidly couples the oil chamber to the hydraulic borehole, and a hydraulic cylinder assembly configured to be at least partially received within the hydraulic borehole, in view of the teachings of Theobald, to provide an integrated, single component hydraulic actuator system which improves efficiency by, for example, avoiding the need to interconnect the subcomponents of such a hydraulic system by separate small diameter hydraulic lines (as suggested by Theobald).
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).
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.).
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 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, Theobald, 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 Theobald to include a hydraulic borehole in the housing, and a hydraulic cylinder assembly at least partially received in the housing, and as modified in view of Wright to include a compressible member, etc.), comprising:
providing a housing defining a gas chamber (i.e., 17 of Nakamura), an oil chamber (11, 12, 13 of Nakamura), a hydraulic borehole (i.e., corresponding to 26 of Theobald), and a fluid passage (13C of Nakamura), the fluid passage fluidly coupling the oil chamber to the hydraulic borehole (as taught by Theobald);
at least partially positioning a hydraulic cylinder assembly (i.e., corresponding to 24, 30 of Theobald) within the hydraulic borehole of the housing (see Theobald, fig. 2);
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 the 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 the oil chamber from the gas chamber;
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).
Regarding claims 21, 23 & 24, the accumulator of Nakamura, as modified in view of Theobald and 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), 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, 11-14, 16, 19, 25 & 26 are rejected under 35 U.S.C. 103 as being unpatentable over Nakamura in view of Theobald and 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;
a fluid passage (13C) configured to fluidly couple the oil chamber to a hydraulic cylinder assembly (see, e.g., paras. 2 & 28; published claim 1, etc.);
wherein a stop (21) for the second piston is formed in a housing (6-10);
wherein the first gas chamber (18), second gas chamber (17), oil chamber (11-13), and fluid passage (13C) are defined within the housing (incl. 6-10);
wherein, the first and second piston are independently movable to alter the volume of the oil chamber (i.e., see figs. 1-3; each piston is independently movable, based on the relative pressure difference between the oil chamber pressure and respective pressures in the first and second gas chambers).
Nakamura does not explicitly disclose a hydraulic borehole configured to at least partially receive a hydraulic cylinder assembly, the fluid passage fluidly coupling the oil chamber to the hydraulic borehole, wherein the hydraulic borehole is defined within the housing; or 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.
Theobald teaches (fig. 2) a hydraulic assembly (12) comprising an oil chamber (i.e. the chamber of either accumulator 16a or 16b which is in communication with hydraulic borehole 26 as shown), an accumulator piston (36) separating the oil chamber from an opposing biasing chamber (i.e., the chambers having springs as shown, but Theobald suggests that other accumulator designs can be used), a hydraulic borehole (26) configured to at least partially receive a hydraulic cylinder assembly (24, 30), a fluid passage fluidly coupling the oil chamber of the accumulator to the hydraulic borehole (as shown), wherein the accumulator biasing chamber, accumulator oil chamber, hydraulic borehole, and fluid passage are each defined within a housing (as shown).
Theobald explains that this assembly is “designed as a single component” having the various subcomponents, including the accumulators “integrally formed with the actuator 12 as one member” (col. 3, lines 64-68).
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 including a hydraulic borehole within the housing, the hydraulic borehole configured to at least partially receive a hydraulic cylinder assembly, wherein the fluid passage fluidly couples the oil chamber to the hydraulic borehole, in view of the teachings of Theobald, to provide an integrated, single component hydraulic actuator system which improves efficiency by, for example, avoiding the need to interconnect the subcomponents of such a hydraulic system by separate small diameter hydraulic lines (as suggested by Theobald).
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…”]).
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, 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 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), an oil chamber (11, 12, 13), and a fluid passage (13C) configured to fluidly couple the oil chamber to a hydraulic cylinder assembly (see, e.g., paras. 2 & 28; published claim 1, etc.); and
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 the housing to define a hydraulic borehole, the fluid passage fluidly coupling the oil chamber to the hydraulic borehole, and further does not disclose a hydraulic cylinder assembly configured to be at least partially received within the hydraulic borehole; or 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.
Theobald teaches (fig. 2) a hydraulic assembly (12) comprising an oil chamber (i.e. the chamber of either accumulator 16a or 16b which is in communication with hydraulic borehole 26 as shown), an accumulator piston (36) separating the oil chamber from an opposing biasing chamber (i.e., the chambers having springs as shown, but Theobald suggests that other accumulator designs can be used), a hydraulic borehole (26) configured to at least partially receive a hydraulic cylinder assembly (24, 30), a fluid passage fluidly coupling the oil chamber of the accumulator to the hydraulic borehole (as shown), wherein the accumulator biasing chamber, accumulator oil chamber, hydraulic borehole, and fluid passage are each defined within a housing (as shown).
Theobald explains that this assembly is “designed as a single component” having the various subcomponents, including the accumulators “integrally formed with the actuator 12 as one member” (col. 3, lines 64-68).
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 including a hydraulic borehole within the housing, wherein the fluid passage fluidly couples the oil chamber to the hydraulic borehole, and a hydraulic cylinder assembly configured to be at least partially received within the hydraulic borehole, in view of the teachings of Theobald, to provide an integrated, single component hydraulic actuator system which improves efficiency by, for example, avoiding the need to interconnect the subcomponents of such a hydraulic system by separate small diameter hydraulic lines (as suggested by Theobald).
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…”]).
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, 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 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.
Regarding claims 25 & 26, the accumulator of Nakamura, 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 is a coil spring.
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Nakamura in view of Theobald and 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 14 May 2026 have been fully considered.
Except for the rejections on the grounds of double patenting, applicant’s amendments to the claims have overcome the grounds of rejection set forth in the previous action. However, new or otherwise amended grounds of rejection have been applied to the claims in this action, as necessitated by applicant’s amendments.
With respect to the double patenting rejections, as noted in the advisory action of 29 May 2026, applicant’s amendments to the claims largely incorporated additional limitations also recited in US 12,031,556. As set forth in this action, the double patenting rejections in this action have been amended as necessitated by applicant’s amendment.
Conclusion
The prior art made of record in the attached PTO-892 and not relied upon is considered pertinent to applicant's disclosure.
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/Richard K. Durden/Examiner, Art Unit 3753
/KENNETH RINEHART/Supervisory Patent Examiner, Art Unit 3753
Prosecution Insights