DETAILED ACTION
This action is responsive to the following communications: Application filed on 11/12/2024.
Claims 1-20 are presented for Examination. Claims 1 and 11 are independent.
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 .
Drawings
The drawings are objected to because labels in the figures are vague in the images. Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. The figure or figure number of an amended drawing should not be labeled as “amended.” If a drawing figure is to be canceled, the appropriate figure must be removed from the replacement sheet, and where necessary, the remaining figures must be renumbered and appropriate changes made to the brief description of the several views of the drawings for consistency. Additional replacement sheets may be necessary to show the renumbering of the remaining figures. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 1-20 are rejected under 35 U.S.C. 112(a) or pre-AIA 35 U.S.C. 112, first paragraph, as failing to comply with the written description requirement.
Claims 1, and 11 recite an "active front end unit or rectifier" configured to perform a complex sequence of operations: rectify supplied AC power, regulate and maintain a pre-set DC power bus voltage, and invert generated DC power back to AC when the generated DC power supplied to the DC power bus by the inverter exceeds the pre-set DC power bus voltage.
While the specification (e.g., [0008], [0036], [0038]) generally mentions an active front end unit and its function in maintaining a DC bus voltage and inverting power, it lacks the detailed structural and functional description necessary to demonstrate that the inventor was in possession of the full scope of this claimed functionality at the time of filing. Specifically, "Active front end unit or rectifier"; these limitations combine two potentially distinct electrical components (a rectifier vs. a more advanced active front end unit capable of bi-directional power flow and active control). The specification does not adequately describe the internal architecture, control logic, or specific components that would enable a single unit or combination thereof to reliably perform all the claimed functions (rectification, voltage regulation, and inversion based on a dynamic bus condition). The term "active front end unit or rectifier" is broad and could encompass various configurations, but the detailed operation of such a unit, particularly in regulating and inverting based on a pre-set voltage, is not sufficiently described to show possession of all possible embodiments ( see MPEP 2163).
Also recite the limitations of "Regulate and maintain a pre-set DC power bus voltage": The specification mentions maintaining a pre-set DC power bus voltage (e.g., [0036], [0038]), but it fails to provide specific details on how this regulation is achieved across the various operational modes described. For example, it does not describe the control algorithms, sensing mechanisms, or power device switching strategies necessary to precisely regulate and maintain a pre-set voltage under varying load conditions, especially during the dynamic process of recovering regenerative energy. A POSITA would have to engage in undue experimentation to implement such a system with the claimed reliability and precision. (MPEP 2164.01(a))
"Invert the generated DC power into generated AC power… when the generated DC power supplied to the DC power bus by the inverter exceeds the pre-set DC power bus voltage": This conditional inversion is a critical operational aspect of the claim. The specification does not clearly delineate the thresholds, control logic, or coordination between the "inverter" that supplies DC power to the bus and the "active front end unit or rectifier" that then inverts this excess DC power. The mechanism for determining when the generated DC power supplied by the inverter "exceeds" the pre-set voltage (as opposed to the voltage on the bus exceeding it) is not explicitly described, leading to a written description gap ( See MPEP 2163).
For these reasons, the applicant has not provided a sufficiently clear and complete written description of the full scope of the claimed "active front end unit or rectifier" functionality to demonstrate possession thereof at the time of filing.
The application does not enable a person of ordinary skill in the art(POSITA) to make and use the invention as broadly claimed without undue experimentation. The "active front end unit or rectifier" and its control system, as broadly recited, would require a POSITA to perform extensive research and development to arrive at a functional system that can reliably perform all the claimed steps, particularly the precise voltage regulation and conditional inversion under varying operating conditions inherent to a drilling rig.
The disclosure lacks crucial details such as:
Specific circuit topologies for the "active front end unit or rectifier" that can perform both rectification and inversion with voltage regulation.
Control system block diagrams or algorithms detailing how the "pre-set DC power bus voltage" is maintained or how the "exceeds" condition triggers inversion.
Parameters or ranges for the "pre-set DC power bus voltage" and its interaction with system stability.
Without such details, a POSITA would be left to engage in undue experimentation to develop the necessary hardware and software to implement the claimed invention. (MPEP 2164.01(a))
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-20 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor, or for pre-AIA the applicant regards as the invention.
Claims 1, and 11 recite "when the generated DC power supplied to the DC power bus by the inverter exceeds the pre-set DC power bus voltage," renders these claims indefinite. This phrase creates ambiguity for a person skilled in the art for the following reasons:
"Generated DC power... exceeds the pre-set DC power bus voltage":
"Generated DC power" is a measure of power (watts), while "pre-set DC power bus voltage" is a measure of potential (volts). Power cannot "exceed" voltage in a directly comparable electrical sense. This is an apples-to-oranges comparison. A POSITA would be uncertain as to what condition is being claimed here. Does it mean:
When the magnitude of the power being supplied causes the voltage to exceed the preset?
When the rate of power generation is such that, if not managed, it would lead to a voltage excursion above the preset?
Is "exceeds" meant to refer to a voltage on the bus that results from the "generated DC power"? If so, the language is imprecise and confusing.
Lack of clear antecedent basis for "generated DC power" in relation to the "pre-set DC power bus voltage": While the claims discuss a "DC power bus" and a "pre-set DC power bus voltage," the mechanism by which "generated DC power" directly "exceeds" this voltage is not clearly defined or conventionally understood in electrical engineering terms. This makes it impossible for a POSITA to determine the metes and bounds of the claimed condition with reasonable certainty (see MPEP2173.05(a)).
This indefinite language fails to particularly point out and distinctly claim the invention, leaving a POSITA to guess at the meaning of a critical operational parameter.
Appropriate correction is requested.
Since the independent claim 1 is rejected under 35 U.S.C. 112(b) and hence the dependent claims of 1 are also rejected under 35 U.S.C. 112(b).
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 of this title, 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 1-20 are rejected under 35 U.S.C. §103 as being unpatentable over Orban et al (US 2019 / 0115758 A1) in view of Pedersen(US2018/0034280).
Regarding independent claim 1, Orban et al teach that a system for recovering energy created during operation of a drawworks winch on a drilling rig located at a well site into electrical energy that is then supplied back to other electrical equipment located at the well site, the drawworks winch operatively coupled to a top drive unit and drill pipe and associated equipment via a cable or gear drive, wherein the top drive unit and the associated equipment is raised and lowered when the drawworks winch is operated by the electric motor (Fig.1 and [0023]-[0024]), the system comprising:
an inverter (Fig.2: 214,245) comprising a direct current (DC) input and an alternating current (AC) output, the AC output operatively coupled to the electric motors, the inverter configured to invert DC power supplied to the DC input into AC power that is outputted from the AC output to power the electric motor (Fig. 2:214,DC1, DW 216 motor);
a DC power bus operatively coupled to the DC input of the inverter(Fig.2: DC1); and
Orban et al fail to teach but Pedersen teaches that an active front end unit or rectifier comprising a DC output and an AC input, the DC output operatively coupled to the DC power bus, the active front end unit or rectifier configured to rectify a source of supplied AC electric power coupled to the AC input into DC power that is outputted onto the DC power bus (Fig. 1, 2, 3, [0015], [0020], showing AC-DC power converters for its drilling rig system, converting AC from generators to DC for the DC bus); the active front end unit or rectifier configured to regulate and maintain a pre-set DC power bus voltage on the DC power bus (Fig.3: showing power system sections designed to manage power and maintain stability, implying active management of bus voltages through switches 113-132, 140); the active front end unit further configured to invert the generated DC power into generated AC power that is outputted from the AC input when the generated DC power supplied to the DC power bus by the inverter exceeds the pre-set DC power bus voltage ( Fig. 3, 103,105).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the invention, to combine the power conversion and DC link control taught by Orban with the drilling rig power distribution system of Pedersen to achieve improved energy efficiency and management. The problem of managing regenerative energy from large motors, like those on drilling rigs, is well-known, and applying established VFD (Orban:[0054]) regenerative braking techniques to a drilling rig power system (Pedersen) to recover energy and supply it back to the grid or other loads is a logical design choice to enhance overall efficiency and reliability, thereby addressing a known need in the art for efficient energy utilization on drilling rigs.
Regarding claim 2, Orban et al fail to teach but Pedersen teaches that further comprising: a battery operatively coupled to the DC power bus (Fig. 3, [0015], [0027], explicitly disclosing energy storage (e.g., battery) connected to the DC bus that can absorb and supply energy).
Regarding claim 3, Orban et al teach that a DC-to-DC voltage regulator (Fig.2 : Chopper) operatively coupled between the battery and the DC power bus, the DC-to-DC voltage regulator configured to maintain a minimum DC voltage on the DC power bus ([0062]).
Regarding claim 4, Orban et al teach that a brake resistor operatively coupled to the DC power bus, the brake resistor configured to dissipate excess DC power when the DC power bus voltage exceeds a maximum DC voltage (Fig.2:208).
Regarding claim 5, Orban et al teach that an AC power bus, the AC input of the active front end unit or rectifier operatively coupled to the AC power bus (Fig. 2: AC).
Regarding claim 6, Orban et al teach that other electrical equipment operatively coupled to the AC power bus( Fig. 1, 2, 3).
Regarding claim 7, Orban et al teach that wherein the other electrical equipment comprises a mud pump(Fig.2:260; PUMP).
Regarding claim 8, Orban et al teach that a rectifier and a second inverter for the mud pump, the rectifier and the second inverter configured to provide power to the mud pump from the AC power bus(Fig. 2, 3, showing power converters (e.g., VFD,261) providing power to loads from the AC bus (AC); the use of rectifiers and inverters (206,261) for powering PUMPS,260 and [0032]).
Regarding claim 9, Orban et al teach that wherein the AC power bus is operatively coupled to a source of commercial AC power ([0041]).
Regarding claim 10, Orban et al teach that wherein the electric motor comprises an asynchronous/induction motor or a synchronous/permanent magnet motor." (Fig.2 shows a VFD for an "electric motor" (261); both asynchronous/induction and synchronous/permanent magnet motors are well-known types of electric motors commonly used with VFDs and power systems as described in Orban and Pedersen, and do not present any surprising or non-obvious features).
Regarding independent claim 11, Orban et al teach that a method for recovering energy created during operation of a drawworks winch on a drilling rig located at a well site into electrical energy that is then supplied back to other electric equipment located at the well site, the drawworks winch operatively coupled to and operated by an electric motor, the drawworks winch operatively coupled to a top drive unit and drill pipe and associated equipment via a cable or a gear drive, wherein the top drive unit and associated equipment is raised and lowered when the drawworks winch is operated by the electric motor(Fig.1 and [0023]-[0024]), the method comprising the steps of:
operating a system operatively coupled to the electric motor (Fig.1,2), the system further comprising:
a inverter (Fig.2: 214,245) comprising a direct current (“DC”) input (Fig.2:DC1) and an alternating current (“AC”) output, the AC output operatively coupled to the electric motors ([0080] and Fig.2), the inverter configured to invert DC power supplied to the DC input into AC power that is outputted from the AC output to power the electric motor, the inverter further configured to rectify AC electric power generated by the electric motor into generated DC power that is outputted from the DC input when the top drive unit is being lowered thereby causing the motor to be in a negative torque operating condition,
a DC power bus operatively coupled to the DC input of the inverter(Fig.2: DC1), and
Orban et al fail to teach but Pedersen teaches that an active front end unit or rectifier comprising a DC output and an AC input, the DC output operatively coupled to the DC power bus(Fig. 1, 2, 3, [0015], [0020], showing AC-DC power converters for its drilling rig system, converting AC from generators to DC for the DC bus), the active front end unit or rectifier configured to rectify a source of supplied AC electric power coupled to the AC input into DC power that is outputted onto the DC power bus, the active front end unit or rectifier configured to regulate and maintain a pre-set DC power bus voltage on the DC power bus, the active front end unit further configured to invert the generated DC power into generated AC power that is outputted from the AC input when the generated DC power supplied to the DC power bus by the inverter exceeds the pre-set DC power bus voltage;
supplying the source of supplied AC electric power to the system to power the electric motor to operate the drawworks winch;
producing generated DC power with the electric motor when the electric motor is in a negative torque condition when the top drive unit is being lowered, wherein the generated DC power is outputted from the DC input of the inverter associated with the electric motor that is in the negative torque condition onto the DC power bus; and
powering the other electrical equipment with the generated AC power when the generated DC power comprises a DC voltage that exceeds the pre-set DC power bus voltage( Fig. 3, 103,105).
Regarding claim 12, Orban et al fail to teach but Pedersen teaches that further comprising the step
of: powering a battery operatively coupled to the DC power bus Fig. 3, [0015], [0027], explicitly disclosing energy storage (e.g., battery) connected to the DC bus that can absorb and supply energy).
Regarding claim 13, Orban et al teach that the step of: maintaining a minimum DC voltage on the DC power bus with a DC-to-DC voltage regulator (Fig.2 : Chopper) operatively coupled between the battery and the DC power bus([0062]).
Regarding claim 14, Orban et al teach that of: dissipating excess DC power when the DC power bus voltage exceeds a maximum DC voltage with a brake resistor operatively coupled to the DC power bus (Fig.2:208).
Regarding claim 15, Orban et al teach that further comprising the step
of: supplying a source of commercial AC power to the AC power bus, the AC input of the active front end unit or rectifier operatively coupled to the AC power bus (Fig. 2: AC).
Regarding claim 16, Orban et al teach that comprising the step
of: powering other electrical equipment operatively coupled to the AC power bus( Fig. 1, 2, 3).
Regarding claim 17, Orban et al teach that wherein the other electrical equipment comprises a mud pump(Fig.2:260; PUMP).
Regarding claim 18 Orban et al teach that comprising the step
of: providing power to the mud pump from the AC power bus with a rectifier and a second inverter for the mud pump(Fig. 2, 3, showing power converters (e.g., VFD,261) providing power to loads from the AC bus (AC); the use of rectifiers and inverters (206,261) for powering PUMPS,260 and [0032]).
Regarding claim 19, Orban et al teach that wherein the electric motor comprises an asynchronous/induction motor or a synchronous/permanent magnet motor ([0041]).
Regarding claim 20, Orban et al teach that comprising the step
of: providing generated AC power from the AC input of the active front end unit or rectifier to the source of supplied AC electric power when the generated DC power supplied to the DC power bus by the inverter exceeds the pre-set DC power bus voltage (Fig.2 shows a VFD for an "electric motor" (261); both asynchronous/induction and synchronous/permanent magnet motors are well-known types of electric motors commonly used with VFDs and power systems as described in Orban and Pedersen, and do not present any surprising or non-obvious features).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MUHAMMAD S ISLAM whose telephone number is (571)272-8439. The examiner can normally be reached 9:30am to 6:00pm.
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/MUHAMMAD S ISLAM/Primary Examiner, Art Unit 2837
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