Patent Application
20200318569
The present disclosure relates generally to systems and strategies for trimming electronically controlled components in a machine system, and more particularly to automatically updating electronic trim files in a machine system each time a machine control system is activated, using electronic trim files resident on the electronically controlled components.
Internal combustion engines are a well-known type of machine system widely used for more than a century. In a typical design, a fuel is combusted with air in a cylinder to produce a rapid rise in pressure and temperature that drives a piston to rotate a crankshaft. The power output of the engine can be used in virtually innumerable ways, such as providing rotational power for vehicle propulsion, rotating parts in an electrical generator to generate electrical power, pressurizing or transferring liquids or gases, and many others. As the design and sophistication of internal combustion engines has continued to advance, engineers demand ever-improving performance and reliability from internal combustion engine components.
In recent decades certain emissions regulations for engines have become increasingly stringent. Engineers have looked to fuel systems, among other engine systems, for precise electronic control to enable or support engine operation in a way that allows production of certain emissions to be limited. For example, in a direct injected compression ignition engine it has been discovered that relatively precise fuel injection timing, duration, amount, and so-called rate shape can assist in achieving not only a desired emissions profile of the engine but also relatively high fuel efficiency in many instances. The precise control required to implement these and many other strategies can require relatively fast-moving internal components, rapid energizing and deenergizing of electrical actuators, and tight mechanical tolerances. Certain ostensibly identical machine system components, notably but not exclusively electronically controlled fuel injectors, can function slightly differently in service even when subjected to and controlled according to nominally identical conditions. For example, different operational and performance results can be observed in fuel injectors responsive to the same control signal waveform
Fuel injectors and other machine system components can be electronically trimmed to obtain desired operation and performance. In one strategy, fuel injectors are tested under relatively tightly controlled conditions at the factory, and electronic trim files produced that can be used to enable an electronic control unit to obtain the desired outcomes when the fuel injectors are placed in service. A known problem with such an approach is that human error in obtaining or loading trim files can lead to one or more fuel injectors being associated with an incorrect trim file. One automated electronic trim strategy for a fuel injector is known from U.S. Pat. No. 6,588,398 to Rodier.
In one aspect, a method of operating a machine system includes activating an on-board electronic control system of a machine, and triggering, based on the activating of the on-board electronic control system, interrogation of a plurality of electronically controlled components installed in the machine by a computer of the on-board electronic control system. The method further includes reading, during the interrogation, a plurality of electronic trim files each resident on a different one of the plurality of electronically controlled components. The method further includes populating a data structure on a machine readable storage medium in the on-board electronic control system with the plurality of electronic trim files, and outputting control signals each based on the corresponding one of the plurality of electronic trim files to each of the plurality of electronically controlled components. The method still further includes running the machine system after the populating of the data structure based on operation of the plurality of electronically controlled components responsive to the outputted control signals.
In another aspect, a machine system includes at least one computer having a processor and a machine readable controller storage medium storing a data structure. The machine system further includes a plurality of electronically controlled components structured for installation in a machine and each including a machine readable component storage medium storing a unique component identifier and a unique electronic trim file. The machine system further includes a communication link connecting the at least one computer and the plurality of electronically controlled components. The at least one computer is structured to detect activation of the on-board electronic control system in the machine, and trigger, based on detecting the activation of the on-board electronic control system, interrogation of the plurality of electronically controlled components. The at least one computer is further structured to read, during the interrogation, each of the unique component identifiers and unique electronic trim files from the machine readable component storage mediums of the plurality of electronically controlled components, and to populate the data structure with the unique component identifier and the unique electronic trim file of each of the plurality of electronically controlled components. The at least one computer is still further structured to output control signals each based on the corresponding unique electronic trim file to each of the plurality of electronically controlled components, and to run the machine system based on operation of the plurality of electronically controlled components responsive to the outputted control signals.
In still another aspect, a method of reducing servicing errors in a machine system includes deactivating an electronic control system of a machine, and activating the electronic control system. The method further includes triggering, based on the activating of the electronic control system, interrogation of a plurality of electronically controlled components installed in the machine by a computer of the electronic control system, and machine reading, during the interrogation, a plurality of electronic trim files each resident on a different one of the plurality of electronically controlled components. The method further includes populating a data structure on a machine readable storage medium in the electronic control system with the plurality of electronic trim files, and overwriting, by way of the populating of the data structure, a plurality of previously stored electronic trim files mis-matched to the plurality of electronically controlled components. The method still further includes outputting control signals based on the corresponding electronic trim file to each of the plurality of electronically controlled components, and operating the plurality of electronically controlled components responsive to the outputted control signals.
Referring to
Machine system 10 also includes a fuel system 18 having a fuel supply or tank 20, a fuel pump 24, and a filter 22 positioned fluidly between fuel supply 20 and fuel pump 24. Fuel system 18 further includes a fuel conduit 26 for conveying a fuel, such as a liquid diesel distillate fuel, to engine housing 14. Fuel system 18 may convey fuel for injection into cylinders 16 by way of a plurality of fuel injectors 28 each positioned to extend into one of cylinders 16. In the illustrated embodiment fuel system 18 supplies fuel for pressurization within fuel injectors 28 as further discussed herein. Fuel injectors 28 may be mechanically actuated, such as by way of a camshaft 32 coupled with a cam gear 34 in a generally conventional manner. In other instances, fuel injectors 28 could be hydraulically actuated, with fuel system 18 supplying pressurized fuel for actuating internal components within fuel injectors 28. The actuating fluid could be a fluid different from fuel in other instances, such as engine oil. Fuel injectors 28 are but one type of electronically controlled component to which the present disclosure is applicable, as will be further apparent from the following description. A plurality of the electronically controlled components, in the illustrated case fuel injectors 28, may be structured for interchangeable service in machine system 10. The term “fuel injector” is used interchangeably herein with “electronically controlled component” except where otherwise indicated. Those skilled in the art will appreciate that fuel injectors can be swapped among different, but interchangeable service locations in engine 12. Each of fuel injectors 28 may be controlled, however, by way of electronic trimming in a unique manner relative to the other fuel injectors 28, each with a unique and dedicated electronic trim file established under controlled, consistent, and repeatable conditions such as at the factory. In other instances, electronic trim files could be established in-chassis.
Machine system 10 further includes an on-board electronic control system 36. Control system 36 includes at least one computer for monitoring and controlling any of a variety of different electronically controlled components of machine system 10, including fuel injectors 28. The at least one computer can include an electronic control unit or engine control unit 38 in control signal communication with fuel injectors 28 by way of a control link 42, such as a conventional wiring harness. Control system 36 may also include a communication link 44, such as a single-wire communication link or other wired communication link having a plurality of nodes 48 corresponding to the plurality of different interchangeable service locations. In the illustrated embodiment the plurality of different interchangeable service locations are cylinder locations each occupied by one of fuel injectors 28.
Control system 36 can further include a communication control unit 50 structured by way of software, firmware, or hardware, to manage and relay certain electronic communications between fuel injectors 28 and electronic control unit 38. In a practical implementation strategy, communication control unit 50 can include a dedicated computer processor preconfigured to gather data from each of fuel injectors 28 by way of interrogating fuel injectors 28 as further discussed herein. Control system 36 also includes an activation switch or button 40 that is actuated to activate and/or deactivate control system 36. In an implementation, switch 40 can include a start-stop button or an ignition switch in machine system 10. Each of fuel injectors 28 further includes a machine readable component storage medium 30 resident thereon. Storage mediums 30 can be or include a computer memory storage chip storing a unique component identifier for each fuel injector 28, such as a component number or a serial number. Storage mediums 30 may further store one or more unique electronic trim files for the corresponding fuel injector 28. In other embodiments, electronically controlled components other than fuel injectors could analogously be equipped with a resident machine readable component storage medium storing a unique component identifier and one or more unique electronic trim files consistent with the functional purposes of the electronically controlled component. In still further instances, the unique electronic trim file stored on each component storage medium 30 can include one of a plurality of electronic trim files, including a first electronic trim file for operating the corresponding one of fuel injectors 28 at a first set of operating conditions of machine system 10, a second electronic trim file for operating the corresponding fuel injector 28 at a second set of operating conditions of machine system 10, and potentially additional trim files. For example, a first electronic trim file could be provided for operating the corresponding fuel injector 28 at a low altitude, such as sea level or up to some altitude threshold, and a second electronic trim file for operating machine system 10 at another altitude, above the predetermined altitude threshold. A great many different sets of conditions could be experienced by machine system 10, and a great many different electronic trim files could be resident on each fuel injector 28 for electronic trimming in a desired manner depending upon present machine system operating conditions.
Referring now to
As discussed above a variety of different electronically controlled components are contemplated within the context of the present disclosure. Electronic trimming of electronically controlled components such as fuel injectors, pumps, valves, sprayers, electrical or hydraulic actuators, and many others enables a class of nominally identical components, or an individual component, to behave in a desired and generally consistent manner. In systems where electronic trimming is not used, or is inferior or faulted, a plurality of electronically controlled components might all receive the same control signal such as an electronic control signal waveform, but each respond differently based on a “personality” unique to each individual electronically controlled component. In the case of fuel injectors, an electronic control unit such as electronic control unit 38 can look up control signals such as signal amplitudes, signal timings, signal durations, or other signal characteristics, from a multidimensional map that is populated on the basis of either or both of empirical data or theoretical determinations as to how a given electronically controlled component can be expected to respond. Given the different personalities of the different electronic components, an electronic trim file may be used for each electronically controlled component to enable the control signal to be modified, adjusted, forgone, supplemented, tweaked, et. cetera, to produce the desired outcomes. Electronic trim files used in association with fuel injectors, for instance, could include an offset value, a multiplier, or some other numerical value that allows a map-derived or otherwise determined control signal to be customized for the fuel injector for which it is intended. Different but generally analogous electronic trimming techniques can be used with pumps, certain actuators, valves, sensors, and other electronically controlled components.
Each time a machine system is serviced, some components might have their service locations switched with one another, intentionally or incidentally. Electronically controlled components that appear to need replacement or upgrading can be swapped out for substitute electronically controlled components. A typical example is when an internal combustion engine system is tom down for a top-end overhaul, or less extensively serviced for other purposes, and some or all of its fuel injectors pulled out, cleaned, inspected, and replaced as needed. Some of the fuel injectors might be put back into different service locations. Other fuel injectors might be discarded or idled, and replaced with substitute fuel injectors. In earlier systems a control system commonly stored electronic trim files on the engine control unit or an associated control unit itself, with electronic trim files stored in the system in a way that associated the electronic trim files with specific service locations in the machine system. In other words, an engine control system might store electronic trim files for numerous fuel injectors at addresses in computer memory that correspond to individual cylinder locations. When fuel injectors are rearranged with other fuel injectors within the same set, or substituted with substitute fuel injectors, a mis-match can occur between electronic trim files and the service locations of the fuel injectors. For example, if cylinder 1 had fuel injector 1 prior to service, but cylinder 1 then has fuel injector 2 after service, the fuel injector 2 at the cylinder 1 location could be expected to operate sub-optimally because it would receive control signals based on a mis-matched electronic trim file. Certain techniques have sought to obtain electronic trim files by querying a remote database or the like, and downloading all of the trim files for a set of fuel injectors. Such strategies suffer, however, from the possibility of not only human error but further changes to service locations or fuel injector identity being made after the download, or connectivity problems with a remote database, for instance. As will be further apparent from the following description, the present disclosure addresses these and other concerns.
Referring to
Referring also now to
Referring also now to
Interrogating fuel injectors 28 could include commanding communication control unit 50, with electronic control unit 38, to commence serially interrogating fuel injectors 28 to machine read the electronic trim files each resident on fuel injectors 28. Responsive to one or more interrogation initiation commands from electronic control unit 38, communication control unit 50 could interrogate the fuel injector 28 at cylinder 1, then interrogate the fuel injector at cylinder 2, then at cylinder 3, and so on. Interrogating fuel injectors 28 could further include machine reading the unique component identifier stored on the machine readable storage medium 30 of each one of fuel injectors 28. From block 240 flowchart 200 can advance to a block 250 to transmit component identifiers and trim files over communication link 44 to a computer such as electronic control unit 38 in control system 36. Transmitting could include transmitting the data for each fuel injector one at a time, for instance, to communication control unit 50 which then communicates the data to electronic control unit 38. Instead of a wired communication link, it should be appreciated that a radio frequency (RF) communication link or some other wireless communication could instead be used. Communication link 40 could be integrated into the same wiring harness as control link 42.
From block 250, flowchart 200 can advance to a block 260 to populate trim table 82 on memory 78, or potentially on a different machine readable storage medium in control system 36. Populating trim table 82 can also include repopulating trim table 82 at each of a plurality of addresses 84 with the unique component identifier and electronic trim file for a different one of fuel injectors 28. It will be recalled that trim table 82 may be repopulated each time machine system 10 is turned on and control system 36 activated. Accordingly, previously stored trim files and component identifiers may be overwritten by way of the populating of trim table 82 that occurs at block 260. It will also be recalled that previously stored component identifiers and electronic trim files may be mis-matched in trim table 82 to fuel injectors 28. In other words, because some change such as varying a pattern of service locations of fuel injectors 28 or a composition of fuel injectors 28, between an earlier time of deactivating electronic control system 36 and a later time of activating electronic control system 36 may have occurred, mis-matching of electronic trim files and component identifiers is corrected. Servicing errors, including human or machine errors, in machine system 10 are expected to be reduced by way of the repopulating of trim table 82 in the described manner. From block 260 flowchart 200 can advance to block 270 to determine control signals for fuel injectors 28, and then to a block 280 to output the control signals each based on the corresponding one of the plurality of electronic trim files to each of fuel injectors 28. Flowchart 200 may then proceed to a block 300 to run machine system 10 after the populating of trim table 82 based on operation of fuel injectors 28 to inject fuel for combustion into cylinders 16 responsive to the outputted control signals.
The present description is for illustrative purposes only, and should not be construed to narrow the breadth of the present disclosure in any way. Thus, those skilled in the art will appreciate that various modifications might be made to the presently disclosed embodiments without departing from the full and fair scope and spirit of the present disclosure. Other aspects, features and advantages will be apparent upon an examination of the attached drawings and appended claims. As used herein, the articles “a” and “an” are intended to include one or more items, and may be used interchangeably with “one or more.” Where only one item is intended, the term “one” or similar language is used. Also, as used herein, the terms “has,” “have,” “having,” or the like are intended to be open-ended terms. Further, the phrase “based on” is intended to mean “based, at least in part, on” unless explicitly stated otherwise.
