Prosecution Insights
Last updated: April 19, 2026
Application No. 18/774,104

LOW-COST CONTROL FOR CARBON DIOXIDE CONDENSING UNIT

Non-Final OA §102§103
Filed
Jul 16, 2024
Examiner
BRADFORD, JONATHAN
Art Unit
3763
Tech Center
3700 — Mechanical Engineering & Manufacturing
Assignee
Heatcraft Refrigeration Products LLC
OA Round
1 (Non-Final)
76%
Grant Probability
Favorable
1-2
OA Rounds
2y 9m
To Grant
97%
With Interview

Examiner Intelligence

Grants 76% — above average
76%
Career Allow Rate
880 granted / 1159 resolved
+5.9% vs TC avg
Strong +21% interview lift
Without
With
+21.3%
Interview Lift
resolved cases with interview
Typical timeline
2y 9m
Avg Prosecution
26 currently pending
Career history
1185
Total Applications
across all art units

Statute-Specific Performance

§101
1.2%
-38.8% vs TC avg
§103
48.5%
+8.5% vs TC avg
§102
19.3%
-20.7% vs TC avg
§112
25.3%
-14.7% vs TC avg
Black line = Tech Center average estimate • Based on career data from 1159 resolved cases

Office Action

§102 §103
DETAILED ACTION Notice of Pre-AIA or AIA Status The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA . Claim Rejections - 35 USC § 102 The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action: A person shall be entitled to a patent unless – (a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention. Claims 1, 3, 5, and 126-16 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Hudson (US 2020/0284477). As to claim 1, Hudson discloses a system with a condenser unit comprising: a compressor 102 configured to receive refrigerant from a condenser unit input port and provide a compressed refrigerant; a gas cooler 104 configured to receive the compressed refrigerant and provide a first cooled refrigerant at a gas cooler discharge port; an expansion valve 138 configured to receive the first cooled refrigerant and provide a second cooled refrigerant to a condenser unit discharge port; and a first controllable valve 142 configured to receive the first cooled refrigerant and provide a first metered refrigerant combined with the second cooled refrigerant to the condenser unit discharge port (Fig. 1), the first controllable valve configured to selectively open when the refrigerant is subcritical (paragraph 67) and thus when a first temperature at the gas cooler discharge port is below a first temperature threshold. As to claim 3, Hudson discloses the first controllable valve 142 as a shut off valve (paragraphs 67 and 70). As to claim 5, Hudson discloses the first temperature threshold as corresponding to a critical temperature of carbon dioxide (paragraph 67). As to claims 12-16, if a prior art device, in its normal and usual operation, would nec-essarily perform the method claimed then the method claimed will be considered to be anticipated by the prior art device. When the prior art device is the same as a device described in the specification for carrying out the claimed method it can be assumed the device will inherently perform the claimed process. Thus the method as claimed would necessarily result from the normal operation of the apparatus. Claim Rejections - 35 USC § 103 The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action: A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made. Claim 2 is rejected under 35 U.S.C. 103 as being unpatentable over Hudson as applied in the rejection(s) above, and further in view of Buck (US 5,495,720). As to claim 2, Hudson is silent regarding use of any specific type of expansion valve. However, Buck teaches the same configuration of an expansion device 9 and parallel controllable valve 91 (Fig. 1) and states that the simplest use case for the expansion device 9 is a fixed differential expansion valve in the form of a capillary (col. 5, lines 25-35). Therefore it would have been obvious to a person having ordinary skill in the art, before the effective filing date, to modify Hudson such that the expansion valve 138 is a fixed differential expansion valve as claimed and taught by Buck in order to simplify installation and operation of the system. Claim 4 is rejected under 35 U.S.C. 103 as being unpatentable over Hudson as applied in the rejection(s) above, and further in view of Saho (US 2021/0108840). As to claim 4, Hudson does not explicitly teach a first temperature sensor physically attached to the first controllable valve 142. However, Saho teaches that it is known to utilize a temperature sensor 111 physically attached to effect control of a valve (Fig. 1; paragraph 51). Therefore it would have been obvious to a person having ordinary skill in the art, before the effective filing date, to modify Hudson to have a sensor arranged as claimed and taught by Saho because it would provide a straightforward means of controlling the valve 142 to perform the desired system operations. Claims 6-11 and 17-20 are rejected under 35 U.S.C. 103 as being unpatentable over Hudson as applied in the rejection(s) above, and further in view of Ohta (US 7,467,525). As to claim 6, Hudson teaches an evaporator unit having a second controllable valve 106 configured to provide a second metered refrigerant to an evaporator 108 (Fig. 1), but does not explicitly teach that the second controllable valve 106 is configured to selectively open when a second temperature at the evaporator discharge port is below a second temperature threshold. However, Ohta teaches that it is known to control the opening of a second controllable valve 12 in a supercritical system based on temperature measured at an outlet of evaporator 9 (Fig. 1). As such it would have been obvious to a person having ordinary skill in the art, before the effective filing date, to modify Hudson to be configured such that the second controllable valve 106 is selectively opened when a second temperature at the evaporator discharge port is below a second temperature threshold as claimed in order to control the superheat degree of the system. As to claim 7, the valve 106 can control flow through the refrigerant line and thus is considered to be a shutoff valve. As to claim 8, Ohta teaches a temperature sensor physically attached to the second valve 12 (Fig. 1). As to claim 9, the modified apparatus includes utilizing a controller to actuate the valves based on sensor inputs in the manner as claimed (Hudson, paragraph 73; Ohta, Fig. 4). As to claims 10-11, the modified apparatus does not explicitly teach using pulse width modulation (PWM) for the controllable valves. However, Official Notice is taken that PWM is a common and typical feature of refrigerant valve control that would have been obvious to use in conjunction with the valves of the modified apparatus for the purpose of providing precise flow control. As to claims 17-20, if a prior art device, in its normal and usual operation, would nec-essarily perform the method claimed then the method claimed will be considered to be anticipated by the prior art device. When the prior art device is the same as a device described in the specification for carrying out the claimed method it can be assumed the device will inherently perform the claimed process. Thus the method as claimed would necessarily result from the normal operation of the apparatus. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to JONATHAN BRADFORD whose telephone number is (571)270-5199. The examiner can normally be reached Monday-Friday 8:00 - 4:00 ET. 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, Jerry-Daryl Fletcher can be reached at (571)270-5054. 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. /JONATHAN BRADFORD/ Primary Examiner, Art Unit 3763
Read full office action

Prosecution Timeline

Jul 16, 2024
Application Filed
Jan 15, 2026
Non-Final Rejection — §102, §103 (current)

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Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

1-2
Expected OA Rounds
76%
Grant Probability
97%
With Interview (+21.3%)
2y 9m
Median Time to Grant
Low
PTA Risk
Based on 1159 resolved cases by this examiner. Grant probability derived from career allow rate.

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