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
The amendment filed July 23rd, 2026 has been entered. Claims 1 and 3-8 remain pending in the application. The amendments to the claims have overcome each and every claim objection and 112(b) rejection previously cited in the Non-Final rejection mailed May 06th, 2026. However, the amendment has raised other issues detailed below.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1 and 5-8 are rejected under 35 U.S.C. 103 as being unpatentable over Hiroshi (JP 2004239564), hereinafter Hiroshi in view of Matsubara (US Patent No. 8,899,053), hereinafter Matsubara, Lobb (US Patent No. 3,733,837), hereinafter Lobb, and Kuriyama et al. (US Patent No. 5,447,034), hereinafter Kuriyama.
Regarding claim 1, Hiroshi discloses a first-stage displacer of a Gifford-McMahon (GM) cryocooler (Fig. 6, first stage displacer; Pg. 1, paragraph 1, a displacer, and in particular, simplifies a manufacturing process suitable for use in a Gifford McMahon cycle refrigerator; Pg. 6, paragraph 39, a first-stage displacer similar to the first embodiment), comprising:
a first-stage displacer main body including a regenerator material and a first-stage displacer cylinder that accommodates the regenerator material (Fig. 6 of Hiroshi depicts tubular member 40 to accommodate regenerator material 14);
an upper cap attached to an upper end of the first-stage displacer main body (Fig. 6 of Hiroshi depicts flange 26 to be attached to an upper end of the tubular member 40);
an additional contact seal member mounted between the upper cap and the first-stage displacer cylinder, the additional contact seal member including a sealing ring and a back ring, the sealing ring formed of a synthetic resin material, the back ring adjacent to a radially inner side of the sealing ring and formed of synthetic rubber (Fig. 6 of Hiroshi depicts high-temperature side seal ring 60 to be mounted between flange 26 and tubular member 40; Fig. 7 of Hiroshi depicts O-ring 62 to be adjacent to a radially inner side of the PTFE cap seal 64; Pg. 3, paragraph 30, a PTFE (tetrafluoroethylene resin); Further, Hiroshi discloses the claimed invention except for the back ring formed of synthetic rubber. It would have been obvious to one having ordinary skill in the art at the time the invention was made to form the back ring of synthetic rubber since it has been held to be within the general skill of a worker in the art to select a known material on the basis of its suitability for the intended use or purpose MPEP 2144.07),
However, Hiroshi does not disclose the upper cap to be formed of a metal material.
Matsubara teaches an upper cap of a first-stage displacer to be formed of a metal material (Fig. 7, upper cup 37; Col. 8, lines 13-15, The upper cup 37, which is formed of aluminum, has a disk shape with an insertion hole 37a formed in its center).
Therefore, it would have been obvious before the effective filing date of the claimed invention to modify the upper cap of the first-stage displacer of Hiroshi of claim 1 to be formed of a metal material as taught by Matsubara. One of ordinary skill in the art would have been motivated to make this modification since it has been held to be within the general skill of a worker in the art to select a known material on the basis of its suitability for the intended use or purpose MPEP 2144.07.
Hiroshi as modified further does not disclose at least one piston seal mounted on a side surface of the metal upper cap.
Lobb teaches at least one piston seal mounted in a groove on a side surface of the upper most portion of a displacer (See annotated Fig. 1 of Lobb below, circumferential seal 38 is disposed in a groove A of the upper most portion of the displacer 2).
Hiroshi as modified fails to teach at least one piston seal mounted on a side surface of the metal upper cap, however Lobb teaches that it is a known method in the art of displacer seals to include at least one piston seal mounted in a groove on a side surface of the upper most portion of a displacer. This is strong evidence that modifying Hiroshi as modified as claimed would produce predictable results (i.e. minimizing undesired gas passage (Lobb, Col. 7, lines 15-16)). Accordingly, it would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to modify Hiroshi as modified by Lobb and arrive at the claimed invention since all claimed elements were known in the art and one having ordinary skill in the art could have combined the elements as claimed by known methods with no changes in their respective functions and the combination would have yielded the predictable result of minimizing undesired gas passage (Lobb, Col. 7, lines 15-16).
Further, Hiroshi as modified does not disclose wherein the at least one piston seal includes a piston ring and a tension ring, the piston ring formed of a synthetic resin material, the tension ring adjacent to a radially inner side of the piston ring and formed of a metal material.
Kuriyama teaches a piston seal of a displacer to include includes a piston ring and a tension ring, the piston ring formed of a synthetic resin material, the tension ring adjacent to a radially inner side of the piston ring and formed of a metal material (Fig. 14, seal assembly 61, coil spring ring 65, inner seal ring 64; Col. 19, lines 1-3, 6-10, and 24-25, The coil spring ring 65 is located inside the inner seal ring 64 and it is contacted with the bottom of the annular groove 37 at the bottom side thereof… The inner seal ring 64 is made of polychlorotrifluoroethylene having an coefficient of thermal expansion (contraction) substantially the same as that of phenol resin of which the first and second displacer sections 28 and 29 are made… As shown in FIG. 15, the coil spring ring 65 is formed by spiraling a stainless steel strip 65a; Col. 23, lines 35-40, Although the inner seal ring 64 has been made of 35 polychlorotrifluoroethylene in the third embodiment, same effects can be attained even if the inner seal ring 64 is made of polymethylmethacrylate resin, stainless steel or titanium alloy when the displacer 22 is made of phenol resin).
Hiroshi as modified fails to teach wherein the piston seal includes a piston ring and a tension ring, the piston ring formed of a synthetic resin material, the tension ring adjacent to a radially inner side of the piston ring and formed of a metal material, however Kuriyama teaches that it is a known method in the art of displacer seals to include a piston seal of a displacer to include includes a piston ring and a tension ring, the piston ring formed of a synthetic resin material, the tension ring adjacent to a radially inner side of the piston ring and formed of a metal material. This is strong evidence that modifying Hiroshi as modified as claimed would produce predictable results (i.e. achieving desired low temperatures and refrigerating efficiency within the displacer (Kuriyama, Col. 20, lines 44-47)). Accordingly, it would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to modify Hiroshi as modified by Kuriyama and arrive at the claimed invention since all claimed elements were known in the art and one having ordinary skill in the art could have combined the elements as claimed by known methods with no changes in their respective functions and the combination would have yielded the predictable result of achieving desired low temperatures and refrigerating efficiency within the displacer (Kuriyama, Col. 20, lines 44-47).
Further, the modification of the references described herein results in wherein the metal upper cap has a peripheral groove formed in the metal material on the side surface the metal upper cap, and the piston seal is disposed in the peripheral groove (See annotated Fig. 1 of Lobb below, circumferential seal 38 is disposed in a groove A of the upper most portion of the displacer 2).
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Annotated Fig. 1 of Lobb
Regarding claim 5, Hiroshi as modified discloses the first-stage displacer according to claim 1 (see the combination of references used in the rejection of claim 1 above).
However, Hiroshi as modified does not explicitly disclose wherein the first-stage displacer cylinder is formed of a synthetic resin material.
Kuriyama teaches wherein the first-stage displacer cylinder is formed of a synthetic resin material (Fig. 2, displacer 22; Col. 23, lines 35-40, Although the inner seal ring 64 has been made of 35 polychlorotrifluoroethylene in the third embodiment, same effects can be attained even if the inner seal ring 64 is made of polymethylmethacrylate resin, stainless steel or titanium alloy when the displacer 22 is made of phenol resin).
Therefore, it would have been obvious before the effective filing date of the claimed invention to modify the first-stage displacer cylinder of Hiroshi as modified to be formed of a synthetic resin material as taught by Kuriyama. One of ordinary skill in the art would have been motivated to make this modification since it has been held to be within the general skill of a worker in the art to select a known material on the basis of its suitability for the intended use or purpose MPEP 2144.07.
Regarding claim 6, Hiroshi as modified discloses a Gifford-McMahon (GM) cryocooler (Hiroshi, Pg. 1, paragraph 1, a displacer, and in particular, simplifies a manufacturing process suitable for use in a Gifford McMahon cycle refrigerator) comprising:
the first-stage displacer according to claim 1 (see the combination of references used in the rejection of claim 1 above).
Regarding claim 7, Hiroshi as modified discloses a first-stage displacer assembly of the Gifford-McMahon (GM) cryocooler (Hiroshi, Pg. 1, paragraph 1, a displacer, and in particular, simplifies a manufacturing process suitable for use in a Gifford McMahon cycle refrigerator), comprising:
the first-stage displacer according to claim 1 (see the combination of references used in the rejection of claim 1 above).
However, Hiroshi as modified does not explicitly disclose the first-stage displacer assembly of the GM cryocooler comprising:
a displacer drive shaft; and
wherein the metal upper cap is attached to the upper end of the first-stage displacer main body such that the displacer drive shaft is connected to the first-stage displacer.
Matsubara teaches the first-stage displacer assembly of the GM cryocooler (Fig. 7, displacer 3A) comprising:
a displacer drive shaft (Fig. 7, output shaft 22a, collar 31; Col. 8, lines 28-40, According to this configuration, when the drive unit performs driving to cause the output shaft 22a to rise (move upward in the Z1 direction), the collar 31 attached to the output shaft 22a by the engagement pin 30 also rises. At this point, since the collar 31 is in engagement with the upper cup 37, the upper cup 37 is also urged to rise with the rising of the collar 31. Accordingly, with the rising of the output shaft 22a, the collar 31 in engagement with the upper cup 37 urges the displacer 3A to move upward. That is, the upper cup 37 engages with the output shaft 22a via the collar 31. Accordingly the displacer 3A is caused to rise by the rising of the output shaft 22a); and
wherein the metal upper cap is attached to the upper end of the first-stage displacer main body such that the displacer drive shaft is connected to the first-stage displacer (Fig. 7, upper cup 37, insertion hole 37a; Col. 8, lines 12-17, The upper cup 37 serves as a lid (lid body) to close the upper end portion of the displacer 3A. The upper cup 37, which is formed of aluminum, has a disk shape with an insertion hole 37a formed in its center. The output shaft 22a is inserted in the insertion hole 37a. A hole forming part of the gas passage L1 and an attachment recess).
Hiroshi as modified fails to teach the first-stage displacer assembly of the GM cryocooler comprising: a displacer drive shaft; and wherein the metal upper cap is attached to the upper end of the first-stage displacer main body such that the displacer drive shaft is connected to the first-stage displacer, however Matsubara teaches that it is a known method in the art of displacers for GM cryocoolers to include the first-stage displacer assembly of the GM cryocooler comprising: a displacer drive shaft; and wherein the metal upper cap is attached to the upper end of the first-stage displacer main body such that the displacer drive shaft is connected to the first-stage displacer. This is strong evidence that modifying Hiroshi as modified as claimed would produce predictable results (i.e. transferring rotational motion of the motor into linear motion to drive the displacer provide refrigeration). Accordingly, it would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to modify Hiroshi as modified by Matsubara and arrive at the claimed invention since all claimed elements were known in the art and one having ordinary skill in the art could have combined the elements as claimed by known methods with no changes in their respective functions and the combination would have yielded the predictable result of transferring rotational motion of the motor into linear motion to drive the displacer provide refrigeration.
Regarding claim 8, Hiroshi as modified discloses the first-stage displacer assembly according to claim 7 (see the combination of references used in the rejection of claim 7 above),
wherein the displacer drive shaft includes a collar portion at a tip of the displacer drive shaft (Matsubara, Fig. 7, output shaft 22a, collar 31; Col. 8, lines 28-40, According to this configuration, when the drive unit performs driving to cause the output shaft 22a to rise (move upward in the Z1 direction), the collar 31 attached to the output shaft 22a by the engagement pin 30 also rises. At this point, since the collar 31 is in engagement with the upper cup 37, the upper cup 37 is also urged to rise with the rising of the collar 31. Accordingly, with the rising of the output shaft 22a, the collar 31 in engagement with the upper cup 37 urges the displacer 3A to move upward. That is, the upper cup 37 engages with the output shaft 22a via the collar 31. Accordingly the displacer 3A is caused to rise by the rising of the output shaft 22a), and
the collar portion is sandwiched between the first-stage displacer main body and the metal upper cap in a state where the displacer drive shaft is inserted into an insertion hole of the metal upper cap (Matsubara, Col. 8, lines 19-27, The fixing bolt 34 is inserted in the attachment recess and mates with a screw hole 35 formed in the upper end portion of the displacer 3A, so that the upper cup 37 is fixed to the displacer 3A. In this state of fixation, the collar 31 is positioned below the upper cup 37. Further, the diameter of the insertion hole 37a formed in the upper cup 37 is smaller than the diameter of the collar 31. Accordingly, with the upper cup 37 being fixed to the displacer 3A, the collar 31 is in engagement (contact) with the upper cup 37). Further, the limitations of claim 8 are the result of the modification of references used in the rejection of claim 7 above.
Claims 3-4 are rejected under 35 U.S.C. 103 as being unpatentable over Hiroshi as modified by Matsubara, Lobb, and Kuriyama as applied to claim 1 above, and further in view of Kusaba (JP S61186062), hereinafter Kusaba.
Regarding claim 3, Hiroshi as modified discloses the first-stage displacer according to claim 1 (see the combination of references used in the rejection of claim 1 above).
However, Hiroshi as modified does not disclose comprising:
wherein the at least one piston seal comprises a plurality of the piston seals mounted on the side surface of the metal upper cap.
Kusaba teaches comprising:
wherein the at least one piston seal comprises a plurality of the piston seals mounted on the side surface of a displacer (See annotated Fig. 4 of Kusaba below piston rings 33 are depicted to be disposed ion grooves A’; Pg. 1, piston rings 33 of which synthetic resin C formation was done, such as tetrafluoroethylene resin, are arranged at the lower part of piston 32, and it is-less lubricous and is used. However, piston ring 33 gives the tension by gas pressure, and since it is what therefore carries out a seal whenever it makes it weld by pressure to the sliding surfaces of cylinder 31).
Hiroshi as modified fails to teach wherein the at least one piston seal comprises a plurality of the piston seals mounted on the side surface of the metal upper cap, however Kusaba teaches that it is a known method in the art of displacer seals to include wherein the at least one piston seal comprises a plurality of the piston seals mounted on the side surface of a displacer. This is strong evidence that modifying Hiroshi as modified as claimed would produce predictable results (i.e. redundancy to improve overall system reliability). Accordingly, it would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to modify Hiroshi as modified by Kusaba and arrive at the claimed invention since all claimed elements were known in the art and one having ordinary skill in the art could have combined the elements as claimed by known methods with no changes in their respective functions and the combination would have yielded the predictable result of redundancy to improve overall system reliability.
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Annotated Fig. 4 of Kusaba
Regarding claim 4, Hiroshi as modified discloses the first-stage displacer according to claim 3 (see the combination of references used in the rejection of claim 3 above),
wherein the metal upper cap has a plurality of peripheral grooves formed in the metal material on the side surface of the metal upper cap, and each of the plurality of the piston seals is disposed in a corresponding peripheral groove among the plurality of the peripheral grooves (See annotated Fig. 4 of Kusaba below piston rings 33 are depicted to be disposed ion grooves A’; Pg. 1, piston rings 33 of which synthetic resin C formation was done, such as tetrafluoroethylene resin, are arranged at the lower part of piston 32, and it is-less lubricous and is used. However, piston ring 33 gives the tension by gas pressure, and since it is what therefore carries out a seal whenever it makes it weld by pressure to the sliding surfaces of cylinder 31). Further, the limitations of claim 4 are the result of the modification of references used in the rejection of claim 3 above.
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Annotated Fig. 4 of Kusaba
Response to Arguments
Applicant's arguments filed July 23rd, 2026 have been fully considered but they are not persuasive.
Applicant argues on Pg. 6-9 (as numbered by Applicant) of the Remarks, “First, applicant submits that there is no motivation to combine the references and instead the combination relies on impermissible hindsight. Claim 1 relates to "a first-stage displacer of a Gifford-McMahon (GM) cryocooler" and recites, inter alia, "at least one piston seal mounted on a side surface of the metal upper cap." In such a GM cryocooler, the inherent purpose of the piston seal is to seal the clearance between the displacer and the cylinder to minimize the passage of gas bypassing the regenerator material. Indeed, the present specification explicitly states that the piston seal blocks "a direct gas flow between the upper space 36 and the expansion space 34 through the clearance (that is, a gas flow that bypasses the regenerator material 26a)." See paragraph [0038] of the originally filed specification. The Examiner's cited references also recognize this well-known purpose in a GM cryocooler. For example, Matsubara, which relates to a mechanically driven GM cryocooler, explicitly teaches that a sealing member is provided on the exterior circumferential surface of the displacer "in order to prevent occurrence of a blow-through of a refrigerant gas" between the cylinder and the displacer (Matsubara, col. 4, lines 56-59). Hiroshi similarly discloses a seal ring (30) provided between the cylinder (36) and the displacer (10) containing the regenerator (12) (Hiroshi, paragraph [0004]). On page 6 of the Office Action, the Examiner acknowledges that Hiroshi as modified does not disclose "at least one piston seal mounted on a side surface of the metal upper cap," but asserts that Lobb discloses this feature. Specifically, the Examiner relies on Lobb for teaching "circumferential seal 38 is disposed in a groove A of the upper most portion of the displacer." However, Lobb 's displacer is reciprocated by a differential gas pressure (i.e., a pneumatic drive). Specifically, Lobb explicitly states that "a displacer 2 is located inside a stainless steel cylinder 4 to define therein an expansion chamber 6 and a driving chamber 8" (col. 6, lines 37-40), and "the displacer 2 reciprocates under the action thereacross of a differential pressure created between the gas in the expansion chamber 6 and the gas in the driving chamber 8" (col. 7, lines 48-51 ). In this pneumatic drive context, Lobb teaches that the circumferential seal 3 8 is located on one side of the recess 26 to "minimize passage of gas from the driving chamber 8 to the annular recess 26" (col. 7, lines 14-16). Thus, the purpose of the circumferential seal 38 is merely to control gas pressure for the pneumatic drive mechanism and minimizing gas passage between the driving gas chamber 8 and the annular recess 26. In Lobb, the seal that corresponds to the purpose of the claimed "piston seal," (i.e., preventing regenerator bypass) is indeed "circumferential seal 40" (Lobb, col. 7, lines 17-22). Specifically, Lobb explicitly states that "a circumferential seal 40 which minimizes the passage of gas to or from the expansion chamber 6 by-passing the regenerator 34 by flowing along the annular clearance formed between the outside wall of the displacer 2 and the inside wall of the cylinder 4." Importantly, the circumferential seal 40 is NOT located at the uppermost portion of the displacer, but rather on the lower side of the recess 26, as shown in the Examiner's annotated FIG. 1. Therefore, even if a person of ordinary skill in the art sought to prevent gas from bypassing the regenerator, they would have looked to Lobb 's seal 40 and placed the seal 40 on the displacer body, not at the uppermost portion of the displacer 2 (which the Examiner alleges corresponds to the metal upper cap), whose location is uniquely dictated by its adjacency to the pneumatic drive chamber 8. There is no motivation to arbitrarily select the seal 38, which serves a completely different purpose for a different drive mechanism, and apply its placement to the top of the mechanically driven displacer of Hiroshi/Matsubara, which lacks such a pneumatic drive chamber. Furthermore, the Examiner's combination lacks structural reasoning. While Matsubara discloses a metal upper cap (upper cup 37, col. 8, lines 12-14), Matsubara intentionally provides its sealing member (sealing member 50, col. 4, lines 45-59) on the outer peripheral surface of the displacer body (first-stage displacer 3A) below the upper cup 37, leaving the upper cup 37 without any seal groove, as shown in Fig. 7. On the other hand, Lobb teaches forming a groove in a displacer that is preferably made entirely of a synthetic resin. Specifically, Lobb explicitly states that "the displacer and the cylinder may be moulded from a plastics material" and "a preferable material for forming the displacer is a fiber-based phenolic resin" (Col. 4, lines 59-62). Neither Matsubara nor Lobb teaches or suggests forming a seal groove specifically in a metal component. To extract the groove concept from Lobb's resin displacer and deliberately machine it into Matsubara 's metal cap-especially when Matsubara explicitly chooses to place its seal elsewhere-requires prior knowledge of the claimed invention. Thus, applicant submits that the Examiner's combination is impermissible hindsight reconstruction.”
However, this argument is not persuasive as both seals 38 and 40 of Lobb have the purpose of preventing gas from moving past the seal, therefore, a PHOSITA would look to Lobb when trying to minimize undesired gas passage in the upper region of the displacer (minimizing undesired gas passage (Lobb, Col. 7, lines 15-16)). Further, Lobb’s material preferences for the displacer are purely preferential and not a requirement. This is further evident by Inaguchi et al. (US Patent No. 5,398,511) which teaches the use of a metal displacer material with a groove for a piston seal to reduce changes in material dimensions due to water absorption or temperature changes to mitigate heat loss (Inaguchi, Fig. 24, movable member body 45, groove 45a; Col. 12, lines 11-25, Since the stainless steel which forms the movable member body 45 does not have a water absorbing action, there is no dimensional change caused by the absorption of water during manufacture. Even if the temperature changes, for example the temperature drops, during operation, since the thermal expansion coefficient of the movable member body 45 and that of the cylinder 20 are the same, there is no change in the distance between the bottom of the groove 45a and the inner peripheral surface of the cylinder 20, thus affording a high dimensional accuracy. Even in the case where the piston ring 24 is less elastic, the second and third closed chambers 7, 23 are isolated from each other without leakage of gas and hence the refrigerating performance is further improved). Moreover, the test for obviousness is not whether the features of a secondary reference may be bodily incorporated into the structure of the primary reference; nor is it that the claimed invention must be expressly suggested in any one or all of the references. Rather, the test is what the combined teachings of the references would have suggested to those of ordinary skill in the art. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981). Additionally, in response to applicant's argument that the examiner's conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971). See the rejection of claim 1 above.
Applicant argues on Pg. 9-11 (as numbered by Applicant) of the Remarks, “Second, applicant submits that the claimed invention addresses an unrecognized problem, results in unexpected results, and therefore a person of skill in the art would not have modified the references as suggested. Furthermore, the Examiner's combination fails to account for the specific problem solved by the claimed invention and the unexpected results achieved by the amended claims. Amended Claim I requires, inter alia, that "the metal upper cap has a peripheral groove formed in the metal material on the side surface of the metal upper cap, and the at least one piston seal is disposed in the peripheral groove." Conventionally, as acknowledged in the present specification, a groove for a piston seal was typically formed in a synthetic resin material, such as a cloth-filled phenol resin (paragraphs [0009], [0043] of the originally filed specification). However, the present inventors discovered a specific problem inherent to this conventional structure: the dimensions of the peripheral groove (such as its width or depth) formed in the synthetic resin change over time due to environmental factors such as water absorption or temperature changes during storage (paragraphs [0010], [0043], and [0044]). If the groove dimensions change and exceed the allowable range, gas leaks occur; conversely, if the groove narrows, the sealing member strongly adheres to the resin surface, weakening the pushing force against the cylinder and also leading to gas leakage (paragraph [0010] and [0044]). None of the cited references (Hiroshi, Matsubara, Lobb, and Kuriyama) recognize or even mention this specific problem associated with the dimensional instability of seal grooves formed in resin materials due to water absorption or temperature changes. In fact, Kuriyama-which the Examiner relies upon for the piston seal-explicitly teaches forming the displacer sections out of phenol resin and holding the seal assembly in a groove on the outer circumference of the resin displacer section (Kuriyama, Col. 25, lines 20-22 and 40-42). In other words, Kuriyama employs the very conventional resin groove structure that causes the problem solved by the present invention, yet completely fails to recognize the problem of dimensional changes. Because the prior art fails to recognize the problem to be solved, a person of ordinary skill in the art would have no motivation to modify the prior art structures to arrive at the claimed solution. By forming the upper cap out of metal and providing the peripheral groove directly in the "metal material," the present invention achieves unexpected and highly advantageous results. As explicitly described in paragraph [0046] of the present specification, it is easier to process the peripheral groove with high accuracy in a metal upper cap compared to a synthetic resin body. More importantly, even after long-term use or exposure to various storage environments, the metal upper cap is highly unlikely to experience changes in its groove dimensions (i.e., unaffected by water absorption). Consequently, the sealing performance of the first-stage displacer can be stably maintained for a long period of time. This dimensional stability and the resulting long-term reliability of the sealing performance are unexpected results that far exceed the Examiner's generic assertion of "minimizing undesired gas passage." Since the cited references neither recognize the specific problem solved by the present invention nor suggest the claimed structural solution that yields these unexpected benefits, the Examiner's 103 rejection is improper and should be withdrawn.”
In response to applicant's argument that “Second, applicant submits that the claimed invention addresses an unrecognized problem, results in unexpected results, and therefore a person of skill in the art would not have modified the references as suggested”, the fact that the inventor has recognized another advantage which would flow naturally from following the suggestion of the prior art cannot be the basis for patentability when the differences would otherwise be obvious. See Ex parte Obiaya, 227 USPQ 58, 60 (Bd. Pat. App. & Inter. 1985). Further, Lobb’s material preferences for the displacer are purely preferential and not a requirement. This is further evident by Inaguchi et al. (US Patent No. 5,398,511) which teaches the use of a metal displacer material with a groove for a piston seal to reduce changes in material dimensions due to water absorption or temperature changes to mitigate heat loss (Inaguchi, Fig. 24, movable member body 45, groove 45a; Col. 12, lines 11-25, Since the stainless steel which forms the movable member body 45 does not have a water absorbing action, there is no dimensional change caused by the absorption of water during manufacture. Even if the temperature changes, for example the temperature drops, during operation, since the thermal expansion coefficient of the movable member body 45 and that of the cylinder 20 are the same, there is no change in the distance between the bottom of the groove 45a and the inner peripheral surface of the cylinder 20, thus affording a high dimensional accuracy. Even in the case where the piston ring 24 is less elastic, the second and third closed chambers 7, 23 are isolated from each other without leakage of gas and hence the refrigerating performance is further improved). The Examiner maintains that the combination of Hiroshi as modified results in “at least one piston seal mounted on a side surface of the metal upper cap...wherein the metal upper cap has a peripheral groove formed in the metal material on the side surface of the metal upper cap, and the at least one piston seal is disposed in the peripheral groove”, see the rejection of claim 1 above.
The rejection of independent claim 1 is maintained. The rejections of dependent claims 3-8 are also maintained for at least the reasons described herein.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Inaguchi et al. (US Patent No. 5,398,511) teaches the use of a metal displacer material with a groove for a piston seal to reduce changes in material dimensions due to water absorption or temperature changes to mitigate heat loss.
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to DEVON T MOORE whose telephone number is 571-272-6555. The examiner can normally be reached M-F, 7:30-5.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Frantz Jules can be reached at 571-272-6681. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/DEVON MOORE/Examiner, Art Unit 3763 September 15th, 2026
/FRANTZ F JULES/Supervisory Patent Examiner, Art Unit 3763
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