TULA TECHNOLOGY, INC. Patent applications |
Patent application number | Title | Published |
20140277999 | CAM PHASER CONTROL - Arrangements for stabilizing valve timing adjustment mechanisms such as cam phasers during operation of an engine are described. The described approaches are particularly well suited for use during skip fire control, although they may be used advantageously in other applications as well. In general, the phase of an adjustable phase camshaft is controlled relative to a crankshaft of an engine. In one aspect, at least one of (i) firing events in a skip fire firing sequence, and (ii) dynamically determined valve actuation events are used in the control of the camshaft phase during operation of the engine. In some embodiments, hydraulic pressure within a cam phaser is varied in a manner that maintains the phase of the camshaft substantially more stable through transitory variations in torque applied to the camshaft by the actuation of the valves than would occur without the variations in hydraulic pressure. | 09-18-2014 |
20140251282 | MANIFOLD PRESSURE AND AIR CHARGE MODEL - In one aspect, an engine controller for an engine including multiple working chambers is described. The engine controller includes a mass air charge determining unit that estimates a mass air charge or amount of air to be delivered to a working chamber. Firing decisions made for a firing window of one or more firing opportunities are used to help determine the mass air charge. The engine controller also includes a firing controller, which is arranged to direct firings to deliver a desired output. Fuel is delivered to a working chamber based on the estimated mass air charge. | 09-11-2014 |
20140172272 | INTERNAL COMBUSTION ENGINE CONTROL FOR IMPROVED FUEL EFFICIENCY - A variety of methods and arrangements for improving the fuel efficiency of internal combustion engines based on skip fire operation of the engine are described. | 06-19-2014 |
20140045652 | TRANSITORY TORQUE MODIFICATIONS USING SKIP FIRE CONTROL - Methods and devices are described that utilize skip fire techniques to rapidly meet requests for transitory changes in the output of an engine. Specifically, the fraction or percentage of the working cycles that are fired can be changed during a transitory event so that the engine delivers the desired transitory engine output. Once the transitory event is over, normal engine operation may be restored. The described techniques are useful in a variety of applications that require a relatively quick, but transitory, reduction in engine output to meet vehicle control requirements. One particularly useful application is during transmission shift events. Other representative applications include: loss of traction events, stability control events, wheel hop prevention events, etc. | 02-13-2014 |
20140041641 | CONTROL OF MANIFOLD VACUUM IN SKIP FIRE OPERATION - A variety of methods and arrangements are described for selectively reducing intake manifold pressure in a skip fire engine control system. In some embodiments, a throttle is adjusted to generate a manifold vacuum, which is used for various applications, including but not limited to purging a fuel vapor canister, reducing pressure within a brake vacuum booster reservoir and/or venting gas from a crankcase interior. An engine firing fraction is increased to help maintain a desired torque level. Other techniques for reducing the intake manifold pressure are also described, such as applications involving a return to idle. | 02-13-2014 |
20140041630 | SPLIT BANK AND MULTIMODE SKIP FIRE OPERATION - Various methods and arrangements for operating a skip fire engine control system are described. In one aspect of the invention, a distinct firing sequence is determined for each bank of working chambers that is used to operate the bank in a skip fire manner. Each firing sequence uses a different firing fraction. In another aspect of the invention, a determination is made as to whether a firing sequence should be dynamically generated or selected from a set of predefined firing sequences. | 02-13-2014 |
20140041626 | DRIVE TRAIN SLIP FOR VIBRATION MITIGATION DURING SKIP FIRE OPERATION - A variety of methods and devices for mitigating power train vibration during skip fire operation of an engine are described. In one aspect, the slip of a drive train component (such as a torque converter clutch) is based at least in part upon a skip fire characteristic (such as firing fraction, selected firing sequence/pattern, etc.) during skip fire operation of an engine. The modulation of the drive train component slip can also be varied as a function of one or more engine operating parameters such as engine speed and/or a parameter indicative of the output of fired cylinders (such as mass air charge). | 02-13-2014 |
20140041625 | FIRING FRACTION MANAGEMENT IN SKIP FIRE ENGINE CONTROL - The described embodiments relate generally to skip fire control of internal combustion engines and particularly to mechanisms for determining a desired operational firing fraction. In some embodiments, a firing fraction determining unit is arranged to determine a firing fraction suitable for delivering a requested engine output. The firing fraction determining unit may utilize data structures such as lookup tables in the determination of the desired firing fraction. In one aspect the desired engine output and one or more operational power train parameters such as current engine speed, are used as indices to a lookup table used to select a desired firing fraction. In other embodiments, additional indices to the data structure may include any one of: transmission gear; manifold absolute pressure (MAP); manifold air temperature; a parameter indicative of mass air charge (MAC); cam position; cylinder torque output; maximum permissible manifold pressure; vehicle speed; and barometric pressure. | 02-13-2014 |
20140034010 | ENGINE BRAKING CONTROLLER - In one aspect of the invention, an engine is operated in a skip cylinder engine braking mode. In the skip cylinder engine braking mode, selected working cycles of selected working chambers are deactivated. Other selected working cycles of the selected working chambers are operated in a braking mode. Accordingly, individual working chambers are sometimes deactivated and sometimes operated in the braking mode while the engine is operating in the skip cylinder engine braking mode. Various methods for cylinder control are described, which improve fuel economy, catalytic converter performance, and vehicle NVH characteristics. | 02-06-2014 |
20130291816 | USING VALVE TIMING TO IMPROVE ENGINE ACOUSTICS - A method for improving the operation of an internal combustion engine implementing cylinder deactivation is described. Generally, the pattern of combustion events that are fired and skipped together with the geometry of the exhaust and/or intake system can create unpleasant acoustic issues. By slightly altering the timing of the cylinder intake and exhaust valves, these acoustic issues can be mitigated. The valve timing can be altered on a combustion event by combustion event basis. Alternatively, valve timing for different groups of cylinders can be modified together. | 11-07-2013 |
20130289853 | LOOK-UP TABLE BASED SKIP FIRE ENGINE CONTROL - A variety of skip fire engine controllers and control methods are described that utilize look-up tables, state machines, or other data structures to determine the sequence or ordering of skip-fire firings. In one aspect, a skip fire engine controller utilizes a look-up table to determine when firings are appropriate to deliver a desired engine output. In some embodiments, a firing timing controller tracks a value indicative of the portion of a firing that has been requested, but not yet directed and such information is utilized in the determination of the timing of the firings. The accumulator value is particularly useful when transitioning between different requested firing fractions. | 10-31-2013 |
20130255626 | CONTROL OF A PARTIAL CYLINDER DEACTIVATION ENGINE - A variety of methods and arrangements for managing transitions between operating states for an engine are described. In one aspect, an engine is operated in a particular operating state. A transition is made to another operating state. During that transition, the engine is operated in a skip fire manner. | 10-03-2013 |
20130118443 | SKIP FIRE ENGINE CONTROL - A variety of skip fire engine controllers and control techniques are described. In some preferred embodiments, a skip fire engine controller is provided that includes a firing fraction calculator, an engine settings controller, a firing fraction adjuster and a firing controller. The firing fraction calculator determines a reference firing fraction indicative of a firing fraction suitable for delivering a desired engine output at a reference working chamber firing output. The engine settings controller is arranged to set selected engine settings. The firing fraction adjuster determines an adjusted firing fraction that scales the reference firing fraction appropriately such that the engine will deliver the desired engine output at the current engine settings even when the actual working chamber firing outputs do not equal the reference working chamber firing output. The firing controller direct workings chamber firings in a skip fire manner that delivers the adjusted firing fraction. | 05-16-2013 |
20130096759 | HYBRID POWERTRAIN CONTROL - Methods and arrangements for controlling hybrid powertrains are described. In one aspect, an engine is alternatingly operated at different effective displacements. One displacement delivers less than a requested powertrain output and the other delivers more. A motor/generator system is used to add and subtract torque to/from the powertrain to cause the net delivery of the requested powertrain output. In some embodiments, energy added and subtracted from the powertrain is primarily drawn from and stored in a capacitor (e.g., a supercapacitor or an ultracapacitor) when alternating between effective displacements. In another aspect a hybrid powertrain arrangement includes an engine a motor/generator and an energy storage system that includes both a battery and a capacitor. The capacitor stores and delivers electrical energy to the motor/generator unit during operation of the engine in a variable displacement or skip fire mode. | 04-18-2013 |
20130096758 | HYBRID VEHICLE WITH CYLINDER DEACTIVATION - A variety of methods and arrangements for operating an internal combustion engine and one or more motor/generators in a hybrid vehicle are described. Generally, the engine is operated in a variable displacement or skip fire mode. Depending on the state of charge of an energy storage device and/or other factors, the engine is operated to generate more or less than a desired level of torque. The one or more motor/generators are used to add or subtract torque so that the motor/generator(s) and the engine collectively deliver the desired level of torque. In some embodiments, the engine may be run with a substantially open throttle to reduce pumping losses and improve fuel efficiency. | 04-18-2013 |
20130092128 | FIRING FRACTION MANAGEMENT IN SKIP FIRE ENGINE CONTROL - In various described embodiments skip fire control is used to deliver a desired engine output. A controller determines a skip fire firing fraction and (as appropriate) associated engine settings that are suitable for delivering a requested output. In one aspect, the skip fire controller is arranged to select a base firing fraction that has a repeating firing cycle length that will repeat at least a designated number of times per second at the current engine speed. Such an arrangement can be helpful in reducing the occurrence of undesirable vibrations. | 04-18-2013 |
20130092127 | FIRING FRACTION MANAGEMENT IN SKIP FIRE ENGINE CONTROL - In various described embodiments skip fire control is used to deliver a desired engine output. A controller determines a skip fire firing fraction and (as appropriate) associated engine settings that are suitable for delivering a requested output. In one aspect, the firing fraction is selected from a set of available firing fractions, with the set of available firing fractions varying as a function of engine speed such that more firing fractions are available at higher engine speeds than at lower engine speeds. The controller then direct firings in a skip fire manner that delivers the selected fraction of firings. | 04-18-2013 |
20130066502 | HYBRID VEHICLE WITH CYLINDER DEACTIVATION - A variety of methods and arrangements for operating an internal combustion engine and one or more motor/generators in a hybrid vehicle are described. In various embodiments, the engine is operated in a skip fire mode. Depending on the state of charge of an energy storage device and/or other factors, the engine is operated to generate more or less than a desired level of torque. The one or more motor/generators are used to add or subtract torque so that the motor/generator(s) and the engine collectively deliver the desired level of torque. In some embodiments, the engine may be run with a substantially open throttle to reduce pumping losses and improve fuel efficiency. | 03-14-2013 |
20120143471 | SKIP FIRE INTERNAL COMBUSTION ENGINE CONTROL - A variety of methods and arrangements for controlling the operation of an internal combustion engine in a skip fire variable displacement mode are described. In general, a firing control unit determines working chamber firings during operation of the engine that are suitable for delivering a desired engine output. In one aspect, the firing control unit is arranged to isolate the generation of firing sequences having frequency components in a frequency range of concern and to alter the firing sequence in a manner that reduces the occurrence of frequency components in the frequency range of concern. In another aspect, a filter is arranged to filter a feedback signal to provide a filtered feedback signal that is used in the determination of the working chamber firings. In preferred embodiments, the frequency characteristics of the filter are variable. In various embodiments, the frequency characteristics of the filter vary as a function engine speed and/or a transmission gear ratio. | 06-07-2012 |
20120109495 | SKIP FIRE INTERNAL COMBUSTION ENGINE CONTROL - A variety of methods and arrangements for controlling the operation of an internal combustion engine in a skip fire variable displacement mode are described. In one aspect, the working chamber firing that are selected to deliver the desired engine output are determined at least in part based on torque feedback. The torque feedback may be an indication of the torque output of the engine or the torque experienced at some other location in the drive train. In some embodiments, the torque feedback signal is filtered to remove high frequency components of the torque feedback signal in order to help stabilize the system. In another aspect, other operational parameters are used as feedback in the determination of the firing sequence. In yet another aspect, a filter is arranged to filter a feedback signal to provide a filtered feedback signal that is used in the determination of the working chamber firings. | 05-03-2012 |
20110251773 | INTERNAL COMBUSTION ENGINE CONTROL FOR IMPROVED FUEL EFFICIENCY - A variety of methods and arrangements for improving the fuel efficiency of internal combustion engines are described. In some aspects, methods and arrangements are described for operating an engine in a throttled skip fire mode. In other aspects, methods and arrangements are described for controlling the operational state of a variable displacement engine. | 10-13-2011 |
20110213541 | INTERNAL COMBUSTION ENGINE CONTROL FOR IMPROVED FUEL EFFICIENCY - A variety of methods and arrangements for improving the fuel efficiency of internal combustion engines are described. Generally, an engine is controlled to operate in a skip fire variable displacement mode. Predictive Adaptive control is used to dynamically determine the working cycles to be skipped to provide a desired engine output. | 09-01-2011 |
20110213540 | INTERNAL COMBUSTION ENGINE CONTROL FOR IMPROVED FUEL EFFICIENCY - A variety of methods and arrangements for improving the fuel efficiency of internal combustion engines are described. In some aspects, methods and arrangements are described for operating an engine in a throttled skip fire mode. In other aspects, methods and arrangements are described for controlling the operational state of a variable displacement engine. | 09-01-2011 |
20110208405 | INTERNAL COMBUSTION ENGINE CONTROL FOR IMPROVED FUEL EFFICIENCY - A variety of methods and arrangements for improving the fuel efficiency of internal combustion engines are described. Generally, an engine is controlled to operate in a skip fire variable displacement mode. In various embodiments, the appropriate firings are determined dynamically during operation of the engine on a firing opportunity by firing opportunity basis and/or without the use of predefined firing patterns. | 08-25-2011 |
20110030657 | SKIP FIRE ENGINE CONTROL - A variety of methods and arrangements for controlling the operation of an internal combustion engine in a skip fire variable displacement mode are described. Generally, an engine is controlled to operate in a skip fire variable displacement mode. In the variable displacement mode, selected combustion events are skipped so that other working cycles can operate at better thermodynamic efficiency. More specifically, selected “skipped” working cycles are not fired while other “active” working cycles are fired. Typically, fuel is not delivered to the working chambers during skipped working cycles. In one aspect of the invention, a firing pattern is determined that is not fixed but the active working cycles are selected to favor the firing of working chambers that have recently been fired at least in part to reduce wall wetting losses. In another aspect of the invention, when an active working cycle follows a skipped working cycle in the same working chamber, the quanta of fuel injected for delivery to the working chamber is increased relative to the quanta of fuel that would be delivered to the working chamber when the active working cycle follows another active working cycle in the same working chamber in order to compensate for wall wetting losses that occur during skipped working cycles. | 02-10-2011 |
20100050986 | INTERNAL COMBUSTION ENGINE CONTROL FOR IMPROVED FUEL EFFICIENCY - A variety of methods and arrangements for improving the fuel efficiency of internal combustion engines are described. Generally, an engine is controlled to operate in a skip fire variable displacement mode. Feedback control is used to dynamically determine the working cycles to be skipped to provide a desired engine output. In some embodiments a substantially optimized amount of air and fuel is delivered to the working chambers during active working cycles so that the fired working chambers can operate at efficiencies close to their optimal efficiency. In some embodiments, the appropriate firing pattern is determined at least in part using predictive adaptive control. By way of example, sigma delta controllers work well for this purpose. In some implementations, the feedback includes feedback indicative of at least one of actual and requested working cycle firings. In some embodiments, the appropriate firings are determined on a firing opportunity by firing opportunity basis. Additionally, in some embodiments, an indicia of the current rotational speed of the engine is used as a clock input for a controller used to selectively cause the skipped working cycles to be skipped. | 03-04-2010 |
20100050985 | INTERNAL COMBUSTION ENGINE CONTROL FOR IMPROVED FUEL EFFICIENCY - A variety of methods and arrangements for improving the fuel efficiency of internal combustion engines are described. Generally, an engine is controlled to operate in a skip fire variable displacement mode. Feedback control is used to dynamically determine the working cycles to be skipped to provide a desired engine output. In some embodiments a substantially optimized amount of air and fuel is delivered to the working chambers during active working cycles so that the fired working chambers can operate at efficiencies close to their optimal efficiency. In some embodiments, the appropriate firing pattern is determined at least in part using predictive adaptive control. By way of example, sigma delta controllers work well for this purpose. In some implementations, the feedback includes feedback indicative of at least one of actual and requested working cycle firings. In some embodiments, the appropriate firings are determined on a firing opportunity by firing opportunity basis. Additionally, in some embodiments, an indicia of the current rotational speed of the engine is used as a clock input for a controller used to selectively cause the skipped working cycles to be skipped. | 03-04-2010 |
20100037857 | INTERNAL COMBUSTION ENGINE CONTROL FOR IMPROVED FUEL EFFICIENCY - A variety of methods and arrangements for improving the fuel efficiency of internal combustion engines are described. Generally, an engine is controlled to operate in a skip fire variable displacement mode. Feedback control is used to dynamically determine the working cycles to be skipped to provide a desired engine output. In some embodiments a substantially optimized amount of air and fuel is delivered to the working chambers during active working cycles so that the fired working chambers can operate at efficiencies close to their optimal efficiency. In some embodiments, the appropriate firing pattern is determined at least in part using predictive adaptive control. By way of example, sigma delta controllers work well for this purpose. In some implementations, the feedback includes feedback indicative of at least one of actual and requested working cycle firings. In some embodiments, the appropriate firings are determined on a firing opportunity by firing opportunity basis. Additionally, in some embodiments, an indicia of the current rotational speed of the engine is used as a clock input for a controller used to selectively cause the skipped working cycles to be skipped. | 02-18-2010 |
20100010724 | INTERNAL COMBUSTION ENGINE CONTROL FOR IMPROVED FUEL EFFICIENCY - A variety of methods and arrangements for improving the fuel efficiency of internal combustion engines are described. Generally, selected combustion events are skipped during operation of the internal combustion engine so that other working cycles can operate at a better thermodynamic efficiency. In one aspect of the invention, an engine is controlled to operate in a variable displacement mode. In the variable displacement mode, fuel is not delivered to the working chambers (e.g. cylinders) during selected “skipped” working cycles. During active (“non-skipped”) working cycles, a maximum (e.g., unthrottled) amount of air and an optimized amount of fuel is delivered to the relevant working chambers so that the fired working chambers can operate at efficiencies closer to their optimal efficiency. A controller is used to dynamically determine the chamber firings required to provide the engine torque based on the engine's current operational state and conditions. The chamber firings may be sequenced in real time or in near real time in a manner that helps reduce undesirable vibrations of the engine. | 01-14-2010 |
20100006065 | INTERNAL COMBUSTION ENGINE CONTROL FOR IMPROVED FUEL EFFICIENCY - A variety of methods and arrangements for improving the fuel efficiency of internal combustion engines are described. Generally, an engine is controlled to operate in a skip fire variable displacement mode. Feedback control is used to dynamically determine the working cycles to be skipped to provide a desired engine output. In some embodiments a substantially optimized amount of air and fuel is delivered to the working chambers during active working cycles so that the fired working chambers can operate at efficiencies close to their optimal efficiency. In some embodiments, the appropriate firing pattern is determined at least in part using predictive adaptive control. By way of example, sigma delta controllers work well for this purpose. In some implementations, the feedback includes feedback indicative of at least one of actual and requested working cycle firings. In some embodiments, the appropriate firings are determined on a firing opportunity by firing opportunity basis. Additionally, in some embodiments, an indicia of the current rotational speed of the engine is used as a clock input for a controller used to selectively cause the skipped working cycles to be skipped. | 01-14-2010 |