Patent Application
20220018302
The present application claims priority to Indian Patent Application No. 202041030365, entitled “SYSTEM AND METHOD FOR ENGINE OPERATION,” and filed on Jul. 16, 2020. The entire contents of the above-listed application are hereby incorporated by reference for all purposes.
Embodiments of the subject matter disclosed herein relate to determination of engine parameters over a range of ambient temperature conditions.
Some vehicles include power sources, such as diesel internal combustion engines. Internal combustion engine systems used in certain geographical locations may be subjected to a wide variation in ambient temperatures (e.g., across diurnal cycles). In an engine, power output and engine speed may be adjusted by an operator by selecting a throttle level. Engine operating parameters may be determined by an engine controller based on the selected throttle level. For example, selection of a higher throttle level may correspond to a larger opening of an air intake and a larger fuel delivery to the engine. Due to diurnal variations in ambient conditions, performance of the engine at any given throttle level selected may be affected. It may be desirable to have a system and method that differ from those that are currently available.
In one embodiment, a method for operating an engine may include obtaining one or more ambient environmental conditions, obtaining a desired throttle level for the engine, obtaining one or more determined engine operating parameters based at least in part on the desired throttle level and an engine operating map, and changing the one or more determined engine operating parameters obtained from the engine operating map based at least in part on the one or more ambient environmental conditions being outside of a defined threshold operating range of environmental conditions.
The following description relates to a system and method for the estimation, adjustment, and/or operation of one or more engine parameters in an engine operating over a range of ambient conditions, including some extreme conditions. Various engines and end-use applications are contemplated herein. Suitable engines may include those powered by gasoline, diesel, biodiesel, ethanol, natural gas, and any combination of two or more of the foregoing. Suitable engine systems may include vehicles such as automobiles, trucks, mining and industrial equipment, locomotives and rail vehicles, marine vessels, and aircraft, as well as in some instances stationary power generators.
Rail vehicles may be used to move railcars, and for assembling and disassembling trains in a railyard. Some vehicles may have determined throttle levels that are optimized or otherwise desirable operational points for engines therein. In rail vehicles, these determined throttle levels may be referred to as “notches.” In one example, “notch” may correspond to a distinct speed and load setpoint. Other engine applications may employ this “notch” technique where the engine is physically decoupled from the load but is coupled to a generator or alternator.
In one embodiment, a system and method may account for engine models originally calibrated for smaller variations in temperature conditions as used in an engine operating at higher power ratings during conditions of extreme variations for engines operating at relatively lower power ratings.
In one embodiment, a system is provided that includes an engine and a controller for the engine. The engine may include a plurality of cylinders organized into two cylinder banks. The controller may obtain one or more ambient environmental conditions from one or more sensors. The controller may receive, from an operator, for example, a desired throttle level for the engine. With the desired throttle level, the controller may access an engine operating map for base engine operating parameters. These base engine operating parameters that the controller obtains may be one or more determined engine operating parameters for the engine that are based at least in part on the desired throttle level. The controller may then change the one or more determined engine operating parameters obtained from the engine operating map based at least in part on the obtained ambient environmental conditions being outside of a defined threshold operating range of environmental conditions. The threshold operating range may define extremes of the environment. For example, an extreme environment may be a temperature that is outside of a threshold operating range of temperatures, e.g., greater than about 50 degrees Celsius or less than about negative 50 degrees Celsius. In one embodiment, the controller may assess a normal operating mode of the engine by receiving engine operating parameters corresponding to the normal operating mode and, in response to an extreme external temperature, may adjust the engine operating parameters in a defined and determined manner. The adjustment may differ depending on an engine RPM (e.g., an engine speed) or other factors as set out herein.
In one embodiment, the engine operating parameters may include each of an amount and a pressure of intake air of a first bank of cylinders relative to a second bank of cylinders, and the controller may modify a first operating mode of the first bank differently and independently from a second operating mode of the second bank in response to the obtained ambient environmental conditions being determined to be outside of the defined threshold operating range of environmental conditions. This may be done by, for example, independently controlling a plurality of turbochargers.
According to an embodiment, an engine system as shown in
The engine may operate at a relatively lower power rating, and the operation may be under extreme environmental conditions. Extreme environmental temperature may be nearer the outer boundaries of operating temperatures. On the cold side, extreme cold may approach and exceeds negative 50 degrees Celsius as a threshold temperature. On the hot side, extreme heat may approach and exceed 50 degrees Celsius as a threshold temperature. These temperatures may be further affected by extremes of humidity, pressure, and the like. In one embodiment, the contemplated system and method may reduce fuel consumption and exhaust emissions levels of some exhaust constituents during operation.
During operation, a throttle level (also refereed herein as a notch) may be selected by an operator via a notch selection handle. This may indirectly or directly control one or more of an engine speed, an engine load, a base timing, and a fuel common rail pressure (e.g., from a pre-calibrated engine map at selected ambient temperature conditions). By selecting and/or adjusting one or more engine operating parameters (e.g., from the engine map) for environmental conditions above or below threshold values, engine performance may be improved.
An engine controller 12 (referred to herein as the controller) may form part of a control system 14 for the vehicle. The control system may control various components related to the vehicle. As an example, various components of the vehicle may be coupled to the controller via a communication channel or data bus. The controller may additionally or alternatively include a memory holding non-transitory computer readable storage media (not shown) including code for enabling on-board monitoring and control of vehicle operation.
The controller may receive information from one or more of a plurality of sensors 16. Further, the controller may send control signals to a plurality of actuators 18. The controller, while overseeing control and management of the vehicle, may receive signals from the sensors to determine operating parameters and operating conditions, and may correspondingly adjust various engine actuators to control operation of the vehicle. For example, the engine controller may receive signals from various engine sensors including, but not limited to, engine speed (e.g., via an engine crankshaft position sensor), engine load (e.g., derived from fueling quantity commanded by the engine controller, fueling quantity indicated by measured fuel system parameters, averaged mean-torque data, and/or electric power output from an alternator or generator), mass airflow amount/rate (e.g., via a mass airflow meter), intake manifold air pressure, boost pressure, exhaust pressure, ambient pressure, ambient temperature, ambient humidity, exhaust temperature (e.g., the exhaust temperature entering the turbine, as determined from a temperature sensor), particulate filter temperature, particulate filter back pressure, engine coolant pressure, exhaust oxides-of-nitrogen quantity (e.g., from a NOx sensor), exhaust soot quantity (e.g., from a soot/particulate matter sensor), exhaust gas oxygen level, or the like. Correspondingly, the controller may control the rail vehicle by sending commands to various components such as traction motors, the alternator/generator, cylinder valves, fuel injectors, a throttle level throttle or notch selection handle, a compressor bypass valve (or an engine bypass valve in alternate embodiments), a wastegate, or the like. Other actively operating and controlling actuators may be coupled to various locations in the rail vehicle.
As one example, an engine map may be populated with engine operating parameters corresponding to each throttle level. The engine operating parameters may be optimized or otherwise pre-adjusted for an engine operating at a lower power rating. Also, the engine operating parameters may be used over a wide range of environmental temperature conditions. A plurality of tables and plots may be populated correlating the engine operating parameters, and the tables and plots may be saved in the memory of the controller. During engine operation, an engine operator may select a throttle level and the engine controller may use the engine map to determine corresponding engine operating conditions for the selected throttle level. Also, during engine operation at a certain engine speed, the controller may use the engine map to determine engine operating parameters corresponding to each engine power.
By selecting engine operating parameters from an engine map populated for an engine operating at a lower power rating and over a range of environmental conditions, engine operation may be controlled by adjusting those operating parameters based at least in part on (measured or calculated) environmental conditions. The technical effect of selecting engine operating conditions from the engine map corresponding to a throttle level selected by the operator, and then adjusting those operating conditions based at least in part on measured or calculated environmental conditions, is that fuel consumption may be reduced. By adjusting engine operating parameters relative to base or expected engine operating parameters in response to measured or calculated environmental conditions, such as during environmental temperature conditions that are above or below respective threshold values, emissions levels may be reduced. By populating an engine map and using the engine map during all operating conditions, engine operation may be carried out for warm and cold engines across a range of throttle levels, engine speeds, and power load scenarios.
Referring to
A suitable engine may include a plurality of combustion chambers (e.g., cylinders). The cylinders of the engine receive fuel (e.g., diesel fuel) from a fuel system 103 via a fuel conduit 107. The fuel conduit may be coupled with a fuel common rail and a plurality of fuel injectors. A pressure of the fuel common rail may be adjusted based on engine operating parameters and a throttle level selected by the engine operator. The fuel common rail pressure may be monitored based on a fuel common rail pressure sensor coupled to the fuel common rail.
The engine receives intake air for combustion from an intake passage 114. The intake air includes ambient air from outside of the vehicle flowing into the intake passage through an air filter 160. The intake passage may include a throttle 162 having a throttle plate. In this example, the position of the throttle plate may be varied by the controller via a signal provided to an electric motor or actuator included with the throttle. The throttle may open to a plurality of distinct positions, each position corresponding to a throttle level. In this manner, the throttle may be operated to vary the intake air provided to the combustion chamber in the engine. As an example, the throttle control may have eight positions (as in “notches”), plus an idle position. Throttle level 1 (first throttle level) may correspond to a minimum amount of intake air and fuel being supplied to the engine while and throttle level 8 (eighth throttle level) may correspond to a highest amount of intake air and fuel being supplied to the engine, with throttle levels 2 through 7 (second through seventh throttle levels) increasing in an amount of intake air and fuel supplied to the engine in a sequential, stepwise manner between throttle levels 1 and 8. The engine operator may select the throttle level via actuation of a switch or a pedal. The intake passage may include and/or be coupled to an intake manifold of the engine. Exhaust gas resulting from combustion in the engine is supplied to an exhaust passage 116. Exhaust gas flows through the exhaust passage, to a muffler 117, and out of an exhaust stack 119 of the vehicle.
Each cylinder of engine may include one or more intake valves and one or more exhaust valves. For example, a cylinder may include at least one intake valve and at least one exhaust valve located at an upper region of the cylinder. The intake valve and the exhaust valve may be actuated via respective cam actuation systems coupled to respective rocker arm assemblies. Cam actuation systems may each include one or more cams and may utilize one or more of cam profile switching (CPS), variable cam timing (VCT), variable valve timing (VVT), and/or variable valve lift (VVL) systems that may be operated by the controller to vary valve operation. The positions of the intake valve and the exhaust valve may be determined by valve position sensors. In alternative embodiments, the intake and/or exhaust valve may be controlled by electric valve actuation. For example, a cylinder may alternatively include an intake valve controlled via electric valve actuation and an exhaust valve controlled via cam actuation including CPS and/or VCT systems.
In one example, the rail vehicle is a diesel-electric vehicle. As depicted in
The engine system may include a turbocharger 120. The turbocharger may be arranged between the intake passage and the exhaust passage. In alternate embodiments, the turbocharger may be replaced with a supercharger. The turbocharger increases the pressure of an air charge of ambient air drawn into the intake passage to provide greater charge density during combustion to increase power output and/or engine-operating efficiency. As shown in
In the illustrated embodiment, six pairs of traction motors correspond to each of six pairs of motive wheels of the vehicle. A suitable electrical system may be coupled to one or more resistive grids 126. The resistive grids may dissipate engine torque and/or kinetic traction motor energy via heat produced by the grids. In other alternative embodiments, the vehicle may include a battery bank, a fuel cell, and/or equipment that allows the vehicle to connect to an electrical grid via a third rail or catenary line. Electrical energy from the alternator/generator, the traction motors (operating in dynamic braking mode), and/or the grid connection equipment may be controlled by the system to store energy and/or propel the vehicle.
As shown in
In some embodiments, the engine system may include an aftertreatment system coupled in the exhaust passage upstream and/or downstream of the turbocharger. In one embodiment, the aftertreatment system may include a diesel oxidation catalyst (DOC) and a diesel particulate filter (DPF). In other embodiments, the aftertreatment system may additionally or alternatively include one or more emission control devices. Such emission control devices may include a selective catalytic reduction (SCR) catalyst, a three-way catalyst, a NOx trap, or various other devices or systems. While the engine system shown in
The engine may be operated based on a throttle level (or notch) selected by the engine operator and a pre-calibrated engine map which may be used as a black box transfer function by the controller. As an example, one or more engine operating parameters may be estimated at various environmental conditions from a set of calibration tables during engine operation at a power output at or below approximately (such as within ±5% variation) 1100 kW, the set of calibration tables including each of a first calibration table for estimation of an engine speed, an engine load, a base timing, and a fuel common rail pressure corresponding a selected throttle level, a second calibration table for estimation of a base timing corresponding to an estimated engine speed and an estimated engine power, and a third calibration table for estimation of a fuel common rail pressure corresponding to an estimated engine speed and an estimated engine power.
At 701, the method 700 may include estimating ambient environmental conditions including ambient temperature, pressure, humidity, etc. based on inputs from one or more sensors coupled to the engine.
At 702, the method 700 may include receiving an input of a throttle level (notch) selected by an operator of the engine. The operator may select the throttle level via a switch on a control panel of the engine or by engaging a pedal or a lever to a specific position. As an example, the engine may have numbered throttle levels (notches) and an idle throttle level. The operator may change operation from one throttle level to another during operation of the engine.
Once the input of the selected throttle level is received by the controller, at 704, the method 700 may include determining a set of engine operating parameters corresponding to the selected throttle level (e.g., optimized for engine operation at the selected throttle level and environmental conditions). Selection of a higher throttle level may correspond to a larger opening of an air intake and a larger fuel delivery to the engine. Correspondingly, selection of a lower throttle level (e.g., lower than the higher throttle level) may correspond to a smaller opening of the air intake and a smaller fuel delivery to the engine.
Determination of engine operating parameters may include, at 705, determining an engine speed corresponding to the selected throttle level. The controller may use a plot or a table of the engine map as initial input to determine the engine speed for operating the engine (e.g., at a lower power rating) over a wide variation of environmental temperatures. In one example, the engine may be operated only as a shunter engine (e.g., at lower power ratings).
Determination of engine operating parameters may include, at 706, determining an engine load corresponding to the selected throttle level. The controller may use a plot or a table of the engine map as initial input to determine the engine load for operating the engine (e.g., at a lower power rating) over a wide variation of environmental temperatures.
Determination of engine operating parameters may include, at 707, determining a base timing corresponding to the selected throttle level. In a diesel engine, the base timing may be a timing, relative to a current piston position and crankshaft angle, for injection of fuel into the combustion chamber. Base timing may be measured relative to a top dead center (TDC) position of the piston in the combustion chamber. The base timing may be measured in crankshaft angle relative to the TDC position. The controller may use a plot or a table of the engine map to determine the base timing for operating the engine (e.g., at a lower power rating) over a wide variation of environmental temperatures.
Determination of engine operating parameters may include, at 708, determining a fuel common rail pressure corresponding to the selected throttle level. In a diesel engine, the fuel common rail pressure (also referred to herein as “rail pressure”) may be a pressure of a high-pressure fuel common rail of a high-pressure common rail direct fuel injection system supplying fuel to the combustion chambers via valves/injectors coupled to the high-pressure fuel common rail. A higher fuel common rail pressure may correspond to a higher amount of fuel being delivered to the combustion chamber for a static period of an injector being open. The controller may use a plot or a table of the engine map to determine the fuel common rail pressure for operating the engine (e.g., at a lower power rating) over a wide variation of environmental temperatures.
At 710, the method 700 may include determining if one or more environmental conditions are within respective threshold ranges (e.g., lower than or equal to an upper threshold and/or greater than or equal to a lower threshold, the lower threshold less than the upper threshold). As an example, the controller may determine if the ambient temperature is above a pre-determined threshold temperature. In one example, the pre-determined threshold temperature may be 50° C. If it is determined that the environmental conditions are within respective threshold ranges, the method 700 may proceed to 712, where the method 700 may include maintaining engine operation with the engine operating parameters determined at 704. In one example, the engine operating parameters may be actively maintained. In another example, the engine operating parameters may be permitted to deviate within the scope of typical engine operation across selectable throttle levels.
If it is determined that one or more environmental conditions are outside of respective threshold ranges, the method 700 may proceed to 714, where the method 700 may include adjusting the engine operating parameters based on the one or more environmental conditions. In one example, only the engine speed, the engine load, the base timing, and/or the fuel common rail pressure may be actively adjusted based on the one or more environmental conditions and no other engine operating parameters may be adjusted based on the one or more environmental conditions. In an additional or alternative example, the engine speed, the engine load, the base timing, and/or the fuel common rail pressure may initially be determined based on only the selected throttle level and may only be subsequently adjusted based on the one or more environmental conditions or responsive to a new throttle level being selected. As an example, the engine speed determined at 704 may be reduced if the ambient temperature is measured to be greater than the threshold temperature.
At 802, the method 800 may include receiving (e.g., at the controller) input from an engine sensor indicating the engine speed. As an example, the engine speed may be estimated based on input from an engine crankshaft position sensor.
At 804, the method 800 may include determining (e.g., via the controller) a desired engine power output. As an example, the desired engine power output may be determined based on a throttle level selected by the engine operator. A table (such as the table 500 in
At 806, the method 800 may include determining the base timing (e.g., for fuel injection to a combustion chamber) corresponding to the engine speed and the desired engine power output. The controller may use a table such as (pre-calibrated) table 600 in
In one example, a base timing corresponding to an engine speed and an engine power may be selected from the pre-calibrated table 600, and in response to obtained ambient environmental conditions being outside of a determined range of environmental conditions, engine operation may be increased to a first timing relative to the base timing proportionally with an increase in engine power for each engine speed listed on the table 600 that is below a first determined engine speed threshold, and engine operation may be decreased to a second timing relative to the base timing proportionally with a decrease in engine power for each engine speed listed on the table 600 that is below a determined second threshold engine speed. In one example, the base timing may initially be determined based on only the engine speed and the desired engine power output and subsequently increased to the first timing or decreased to the second timing based on only the obtained ambient environmental conditions being outside of the determined range of environmental conditions.
In some examples, for a constant engine speed (e.g., up to a threshold engine speed, such as 1200 RPM or within ±5% variation thereof), the base timing may increase with an increase in the engine power up to a threshold engine power. As an example, at 225 RPM engine speed and 500 RPM engine speed (e.g., line 302), the base timing may increase approximately 80% from 0 to 100 kW threshold engine power and may be maintained constant therefrom to 1100 kW engine power; at 700 RPM engine speed (e.g., line 304), the base timing may increase approximately 62.5% from 0 to 385 kW threshold engine power and may be maintained constant therefrom to 1100 kW engine power; at 840 RPM engine speed (e.g., line 306), the base timing may increase approximately 50% from 0 to 385 kW threshold engine power and may be maintained constant therefrom to 1100 kW engine power; at 1000 RPM engine speed (e.g., line 308), the base timing may increase approximately 23% from 0 to 385 kW threshold engine power and may be maintained constant therefrom to 1100 kW engine power; and at 1200 RPM engine speed (e.g., line 310), the base timing may increase approximately 13% from 0 to 225 kW threshold engine power and may be maintained constant therefrom to 1100 kW engine power. In some examples above the threshold engine speed, such as at 1350 RPM engine speed (e.g., line 312), the base timing may initially increase and then decrease causing no significant (such as no more than 2%) change in base timing from a lowest engine power of 0 kW to a highest engine power of 1100 kW. At engine speeds above 1350 RPM, the base timing may decrease with an increase from a lowest engine power of 0 kW to a highest engine power of 1100 kW. As an example, at 1500 RPM engine speed (e.g., line 314), the base timing may decrease approximately 19% from 0 to 1100 kW engine power; at 1650 RPM engine speed (e.g., line 316), the base timing may decrease approximately 3.5% from 0 to 1100 kW engine power; and at 1800 RPM engine speed and 1980 RPM engine speed (e.g., lines 318 and 320, respectively), the base timing may decrease approximately 6.5% from 0 to 1100 kW engine power.
At 902, the method 900 may include receiving (e.g., at the controller) input from an engine sensor indicating the engine speed. As an example, the engine speed may be estimated based on input from an engine crankshaft position sensor.
At 904, the method 900 may include determining (e.g., via the controller) a desired engine power output. As an example, the desired engine power output may be determined based on a throttle level selected by the engine operator. A table (such as the table 500 in
At 906, the method 900 may include determining the fuel common rail pressure for fuel injection to a combustion chamber corresponding to the engine speed and the desired engine power output. The controller may use a table such as (pre-calibrated) table 650 in
In one example, a base fuel pressure in a common rail system (e.g., a base fuel common rail pressure) or a base fuel pressure supplied to a cylinder in the engine that corresponds to an engine speed and an engine power may be selected from the pre-calibrated table 650, and in response to obtained ambient environmental conditions being outside of a determined range of environmental conditions, engine operation may be increased to a first fuel pressure relative to the base fuel pressure proportionally with an increase in engine power for each engine speed listed on the table 650 that is below a first determined engine speed threshold, and engine operation may be decreased to a second fuel pressure relative to the base fuel pressure proportionally with a decrease in engine power for each engine speed listed on the table 650 that is below a determined second threshold engine speed. In one example, the base fuel pressure may initially be determined based on only the engine speed and the desired engine power output and subsequently increased to the first timing or decreased to the second timing based on only the obtained ambient environmental conditions being outside of the determined range of environmental conditions.
In some examples, for a constant engine speed (e.g., up to a threshold engine speed, such as 500 RPM or within ±5% variation thereof), the rail pressure may be maintained constant from a lowest engine power of 0 kW to a highest engine power of 1100 kW. As an example, at 225 RPM engine speed and 500 RPM engine speed (e.g., line 402), the rail pressure may remain substantially constant from 0 kW to 1100 kW engine power. In some examples above the threshold engine speed, the rail pressure may increase with an increase in engine power. For instance, the rail pressure may increase with an increase in the engine power up to a threshold engine power. As an example, at 700 RPM engine speed (e.g., line 404), the rail pressure may increase approximately 43% from 0 to 385 kW threshold engine power and may be maintained constant therefrom to 1100 kW engine power; at 840 RPM engine speed (e.g., line 406), the rail pressure may increase approximately 37.5% from 0 to 225 kW threshold engine power and may be maintained constant therefrom to 1100 kW engine power; at 1000 RPM engine speed (e.g., line 408), the rail pressure may increase approximately 33% from 0 to 385 kW threshold engine power and may be maintained constant therefrom to 1100 kW engine power; at 1200 RPM engine speed (e.g., line 410), the rail pressure may increase approximately 30% from 0 to 550 kW threshold engine power and may be maintained constant therefrom to 1100 kW engine power; at 1350 RPM engine speed (e.g., line 412), the rail pressure may increase approximately 40% from 0 to 725 kW threshold engine power and may be maintained constant therefrom to 1100 kW engine power; and at 1500 RPM engine speed (e.g., line 414), the rail pressure may increase approximately 40% from 0 to 550 kW threshold engine power and may be maintained constant therefrom to 1100 kW engine power. As another example, at 1650 RPM engine speed (e.g., line 416), the rail pressure may increase approximately 50% from 0 to 1100 kW engine power; and at 1800 RPM engine speed and 1980 RPM engine speed (e.g., line 418), the rail pressure may increase approximately 52.5% from 0 to 1100 kW engine power. Additionally or alternatively, the increase in rail pressure at higher engine speeds may be incremental in steps.
A method may be provided for estimating engine operating parameters and, responsive to one or more ambient environmental conditions being outside of respective threshold ranges, adjusting the estimated engine operating parameters based on the one or more ambient environmental conditions. The engine operating parameters may be estimated from a first pre-calibrated table of an engine model for the engine operating at or below a lower engine power output (such as 1100 kW or less) over a wide ambient temperature variation (such as ±50° C.). Suitable engine operating parameters may include one or more of the engine speed, the engine load, the base timing, and the fuel common rail pressure corresponding to a (selected) throttle level. A base timing corresponding to an estimated engine speed and an estimated engine load may be estimated based on a second pre-calibrated table of the engine model and a fuel common rail pressure corresponding to the estimated engine speed and the estimated engine load may be estimated based on a third pre-calibrated table of the engine model.
As used herein, an element or step recited in the singular and preceded with the word “a” or “an” should be understood as not excluding plural of said elements or steps, unless such exclusion is explicitly stated. Furthermore, references to “one embodiment” or “one example” of the invention do not exclude the existence of additional embodiments that also incorporate the recited features. Moreover, unless explicitly stated to the contrary, embodiments “comprising,” “including,” or “having” an element or a plurality of elements having a particular property may include additional elements not having that property. The terms “including” and “in which” are used as the plain-language equivalents of the respective terms “comprising” and “wherein.” Moreover, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements or a particular positional order on their objects.
This written description uses examples to disclose the invention, including the best mode, and also to enable a person of ordinary skill in the relevant art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those of ordinary skill in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202041030365 | Jul 2020 | IN | national |
