Patent Description:
<CIT> discloses a method for operating an engine start-stop function for an engine of a motor vehicle. The engine start-stop function executes engine start-stop interventions in the form of an automatic shutting down and a subsequent automatic switching on of the engine, as a function of one or more vehicle states. An engine start-stop intervention determined by the engine start-stop function is selectively prevented as a function of a statement on the number of starting procedures of the engine carried out. <CIT> discloses a method that involves executing a function of motor vehicle system in a repeated manner during the operation of the vehicle. The wear of the motor vehicle influencing variables are determined. The frequency, with which the function of the motor system is carried out, is varied according to determined wear of the motor vehicle influencing variables. <CIT> discloses a vehicle control device for performing control to stop and start an engine according to a traveling state of a vehicle regardless of an operation of stopping and starting the engine by a driver <NUM>. The stopping of the engine <NUM> is limited based on a starting endurance ability of the engine <NUM>. An endurance number of years of a starter can be ensured. If a contribution degree in improving a fuel economy by the stopping of the engine at the time of parking is high, the effect of improving the fuel economy can be suppressed from reducing by prohibiting the automatic stopping of the engine during traveling. The effect of improving the fuel economy by stopping the engine can be enhanced by ensuring the endurance number of years of the starter. As a result, the reduction of fuel economy and ensuring of endurance of the starter can be satisfied. <CIT> discloses a method for controlling the automatic shut-down of an internal combustion engine of an automobile. When shut-down conditions are met for a period of time that exceeds a timer period, said internal combustion engine being provided with a starter suitable for performing a plurality of starting cycles. According to the invention, the timer period is defined according the number of starting cycles performed by the starter. <CIT> discloses a method that involves executing engine stop and start of an internal combustion engine automatically by an automatic stop/start system, and varying frequency of the automated execution of engine stop and start. A stop and go condition is determined based on operating parameters of the stop/start system for determining stop and go condition parameters. Variation of the frequency of the automated execution of engine stop and start is carried out by reduction of the frequency when the stop and go condition parameters are determined. <CIT> discloses a control device for a vehicle with an idle stop device.

One embodiment relates to an apparatus according to claim <NUM>. The apparatus includes a stop/start module in operative communication with an engine. The stop/start module is structured to determine whether a stopping event has occurred, determine whether an inhibiting condition is activated, turn off the engine for at least a portion of time in response to determining that a stopping event has occurred if the inhibiting condition is not active, and determine an actual stop ratio for the engine based on a number of times the engine is turned off in response to determining the occurrences of stopping events. The stop/start module is further structured to activate the inhibiting condition if the actual stop ratio for the engine is greater than a target stop ratio. The inhibiting condition remains activated during the driving event until the actual stop ratio of the engine becomes less than the target stop ratio. The stop/start module is further structured to inhibit automatically turning off the engine if the inhibiting condition is active. The target stop ratio is based on an operating parameter. Activation of the inhibiting condition occurs only at a beginning of a driving event that commences when the engine is manually turned on by an operator and ends when the engine is manually turned off by the operator. Turning off the engine is inhibited in response to determining that an inhibiting condition is activated. The inhibiting condition is activated based on any number of criteria such as engine temperature, battery charge, or other vehicle loads. If an inhibiting condition is activated at a beginning of a driving event, the duration of the inhibiting condition is extended past the actual inhibiting criteria based on the actual stop ratio for the engine being greater than a target stop ratio.

Another embodiment relates to a method according to claim <NUM>. The method includes determining whether a stopping event has occurred, determining an actual stop ratio for the engine based on a number of times the engine is turned off in response to determining the occurrences of stopping events, determining a target stop ratio based on an operating parameter, inhibiting the engine from temporarily turning off based on the actual stop ratio being greater than a target stop ratio. The inhibition remains activated during a driving event until the actual stop ratio of the engine becomes less than the target stop ratio. The method further comprises, if the inhibition is not active, temporarily turning off an engine for at least a portion of time in response to determining that a stopping event has occurred. The inhibition is only activated at a beginning of the driving event that commences when the engine is manually turned on by an operator and ends when the engine is manually turned off by the operator. The inhibiting condition is based on any number of criteria. If an inhibiting condition is present at a beginning of a driving event, the duration of the inhibiting condition may be extended based on the actual stop ratio for the engine being greater than a target stop ratio.

These and other features, together with the organization and manner of operation thereof, will become apparent from the following detailed description when taken in conjunction with the accompanying drawings.

Following below are more detailed descriptions of various concepts related to, and implementations of, methods, apparatuses, and systems for managing automatic stop/start frequency by enabling or disabling a stop/start feature. The various concepts introduced above and discussed in greater detail below may be implemented in any number of ways, as the concepts described are not limited to any particular manner of implementation. Examples of specific implementations and applications are provided primarily for illustrative purposes.

Referring to the Figures generally, the various embodiments disclosed herein relate to systems, apparatuses, and methods of enabling or disabling an automatic stop/start feature of an engine based on various operating conditions and operating parameters. Engine starting can be one of the most detrimental operating modes of an engine. When an engine is started, bearings within the engine have little or no lubrication and may experience excessive wear. After initially starting, the engine undergoes a warm-up period where the engine may experience high temperature transients. Furthermore, during the warm-up period, emission control devices, such as an exhaust gas aftertreatment system, may perform sub-optimally. Also during warm-up, engine lubricant (e.g., oil, etc.) may remain fairly viscous such that a high torque is required to restart the engine, which requires more electrical power. An engine may also be damaged by being shut down when the engine is too hot. For example, after prolonged periods of high-powered operation, portions of the engine may take a finite amount of time to adequately cool even when using a cooling system (e.g., a radiator, a water pump, etc.). Engine damage may also occur if an automatic stop occurs before the engine has sufficiently cooled down, for example, by the occurrence of heat soak-back. Accordingly, it will be appreciated that a stop/start feature should, in some cases, be disabled or temporarily refrained from stopping or starting the engine based on a characteristic of the engine, a current state of the engine, an operating condition of the engine, and so on. Further, engine stop and restart may be disabled for a period of time to limit the number of stop/start events an engine may experience over its operating life.

In pursuing fuel economy improvements in automotive vehicles, engine idle time may be reduced through systems and methods that automatically shut down and restart the engine. Such systems and methods typically shut down the engine whenever the vehicle is not moving and automatically restart the engine when a driver input indicates a desire to launch or otherwise continue driving. However, excessively shutting down and restarting an engine causes excessive wear and affects the durability and useful life of the engine as engine starting may be one of the harshest operational modes of the engine. During initial cranking of the engine, bearing and camshaft lubrication as well as piston-ring/cylinder-wall contact are minimal or non-existent. Furthermore, some engines may be designed to survive an assumed number of start events over the engine's life, which may be based on presumed drive cycles that include only a single start per driving event. Accordingly, an engine configured to automatically stop and then be restarted may have a high risk of premature failures if the stop and restart frequency is substantially high. These risks may be remedied by improving the durability of engine hardware, which in turn may increase costs. One alternative is to limit the number of stops and restarts over the life of the engine.

The number of or frequency of stop/start events may be limited based on a time limit between subsequent stop and restart events. For example, a design-limited maximum number of start events for an engine may suggest a maximum average of thirty starts per hour of operation over the life of the engine. An engine shutdown may then be inhibited if the engine shutdown would occur sooner than two minutes after a previous shutdown or a previous restart. One drawback to this approach is that the operator may observe (or think they observe) inconsistency in the behavior of the stop/start logic. For example, the operator may not be able to tell the difference between a stop in which the engine shuts down and a stop in which the engine does not shut down, which may lead the operator to assume that the stop/start feature is inconsistent or not working properly. Unless the vehicle operator is aware of the time limit, the operator may not understand the stop/start pattern or understand the stop/start logic, particularly if the operator's drive cycle significantly varies day-to-day.

Embodiments of the inventive concepts disclosed herein are directed to performing cumulative engine stop corrections (e.g., inhibiting the stop/start functionality of an engine, etc.) during periods when a stop/start feature may normally be inhibited, such as during and immediately following an engine warm-up period. By consistently inhibiting the automatic stopping and restarting of an engine during and as an extension of the engine warm-up period, the operator of the vehicles may become accustomed to the engine stop/start feature being inhibited during this time and will not expect the engine to automatically stop and restart. Also, enabling automatic engine shutdowns after the engine has warmed-up causes the engine to crank with relatively lower torque requirements (e.g., reduced friction when the engine is warm, etc.) and other advantages. For example, the stop/start inhibiting period may be extended to correct for the cumulative number of engine stops per hour of operation or distance traveled, an expected life of the engine in hours since purchase date, and/or an expected of the engine in operating hours. Various corrective timetables may be employed and the time between automatic shutdown events may be managed in an effort to keep total start events for the life of the engine on a predetermined trajectory. In some embodiments, automatic stops may be inhibited as long as the engine is operating above a desired durability trajectory (e.g., an actual stop ratio is greater than a target stop ratio, etc.), and these inhibiting events may be concentrated as extensions of the engine warm-up period. According to an example embodiment, the implementation of an automatic stop/start feature is based on criteria which indicate an inhibiting condition is not present.

In some embodiments, the inhibiting criteria is not limited to an absolute total number of engine starts over the life of the engine. For example, restarting events implemented by the stop/start logic may tax the robustness of the engine hardware beyond the number of starting events an engine is designed for. In one embodiment, the inhibiting criteria may limit the number of automated restarts incurred due to the stop/start logic (e.g., any restart as a direct result of an automated stop, not accounting for a manual start or stop, etc.). For example, manual starts and stops (e.g., an operator turning a key to start or stop the engine, etc.) may be ignored and not counted as a stop and restart event. Similarly, other starts that may not tax the robustness of the engine may be ignored. For example, some stop and restart events may be relatively brief such that the fluid pressure in the engine's lubrication system does not decay to a low pressure (i.e., minimizing the negative consequences of a subsequent restart, etc.). In another example, some engine systems may include other technologies designed to mitigate certain negative effects of engine starting such that some stop and restart events may not be included in the accounting of the number of stop and restart events that the engine experiences.

Referring now to <FIG>, a schematic diagram of a vehicle <NUM> with a controller <NUM> is shown according to an example embodiment. The vehicle <NUM> may be an on-road or an off-road vehicle including, but not limited to, line-haul trucks, mid-range trucks (e.g., pick-up truck), cars (e.g., sedans, hatchbacks, coupes, etc.), and any other type of vehicle which may include a stop/start feature that automatically shuts down an engine and then restarts the engine after a period of time. Although <FIG> depicts the vehicle <NUM> as including an internal combustion engine <NUM>, the vehicle <NUM> may be powered by any type of engine system. For example, the vehicle <NUM> may be a hybrid vehicle, a full electric vehicle, a hydrogen powered vehicle, and/or a vehicle powered by an internal combustion engine.

As shown in <FIG>, the vehicle <NUM> generally includes a powertrain system <NUM>, vehicle subsystems <NUM>, an operator input/output (I/O) device <NUM>, sensors <NUM> communicably coupled to one or more components of the vehicle <NUM>, and a controller <NUM>. These components are described more fully herein.

Components of the vehicle <NUM> may communicate with each other or foreign components using any type and any number of wired or wireless connections. For example, a wired connection may include a serial cable, a fiber optic cable, a CAT5 cable, or any other form of wired connection. Wireless connections may include the Internet, Wi-Fi, cellular, radio, Bluetooth, etc. In one embodiment, a controller area network (CAN) bus provides the exchange of signals, information, and/or data. The CAN bus includes any number of wired and wireless connections. Because the controller <NUM> is communicably coupled to the systems and components in the vehicle <NUM> of <FIG>, the controller <NUM> is structured to receive data regarding one or more of the components shown in <FIG>. For example, the data may include operation data regarding the operating conditions (e.g., engine temperature data, exhaust aftertreatment temperature data, energy temperature data, etc.) of the engine <NUM> and/or other components (e.g., an exhaust aftertreatment system, a battery system, etc.) acquired by one or more sensors, such as sensors <NUM>. As another example, the data may include an input from operator I/O device <NUM>. As described more fully herein, the controller <NUM> may determine when it is permissible to enable the stop/start feature based on the operation data and operating parameters.

As shown in <FIG>, the powertrain system <NUM> includes an engine <NUM>, a transmission <NUM>, a drive shaft <NUM>, a differential <NUM>, and a final drive <NUM>. As a brief overview, the engine <NUM> receives a chemical energy input (e.g., a fuel such as gasoline, diesel, etc.) and combusts the fuel to generate mechanical energy, in the form of a rotating crankshaft. The transmission <NUM> receives the rotating crankshaft and manipulates the speed of the crankshaft (e.g., the engine revolutions-per-minute (RPM), etc.) to affect a desired drive shaft speed. The rotating drive shaft <NUM> is received by the differential <NUM>, which provides the rotation energy of the drive shaft <NUM> to the final drive <NUM>. The final drive <NUM> then propels or moves the vehicle <NUM>.

The engine <NUM> may be structured as any engine type, including an internal combustion engine, and a full electric motor, among other alternatives. As shown, the engine <NUM> may be structured as any internal combustion engine (e.g., compression-ignition, spark-ignition, etc.) and may be powered by any fuel type (e.g., diesel, ethanol, gasoline, etc.). Similarly, the transmission <NUM> may be structured as any type of transmission, such as a continuous variable transmission, a manual transmission, an automatic transmission, an automatic-manual transmission, a dual clutch transmission, and so on.

Accordingly, as transmissions vary from geared to continuous configurations (e.g., continuous variable transmission), the transmission may include a variety of settings (gears, for a geared transmission) that affect different output speeds based on the engine speed. Like the engine <NUM> and the transmission <NUM>, the drive shaft <NUM>, differential <NUM>, and final drive <NUM> may be structured in any configuration dependent on the application (e.g., the final drive <NUM> is structured as wheels in an automotive application and a propeller in a boat application, etc.). Further, the drive shaft <NUM> may be structured as any type of drive shaft including, but not limited to, a one-piece, two-piece, and a slip-in-tube driveshaft based on the application.

Referring still to <FIG>, the vehicle <NUM> includes the vehicle subsystems <NUM>. As shown in <FIG>, the vehicle subsystems <NUM> may include an exhaust aftertreatment system <NUM>. The exhaust aftertreatment system <NUM> may include any component used to reduce exhaust emissions, such as selective catalytic reduction (SCR) catalyst, a diesel oxidation catalyst (DOC), a diesel particulate filter (DPF), a diesel exhaust fluid (DEF) doser with a supply of diesel exhaust fluid, a plurality of sensors for monitoring the aftertreatment system (e.g., a nitrogen oxide (NOx) sensor, temperature sensors, etc.), and/or still other components. As shown in <FIG>, the vehicle subsystems <NUM> may further include a battery system <NUM>. The battery system <NUM> may include one or more batteries configured to operate various electrical based components of the vehicle <NUM> (e.g., while the engine <NUM> is running, while the engine <NUM> is off, etc.) and provide energy to start the engine <NUM> (e.g., in response to a restart command when the stop/start feature turns off the engine <NUM>, when an operator keys on the engine <NUM>, etc.).

The operator I/O device <NUM> may enable an operator of the vehicle <NUM> (or passenger) to communicate with the vehicle <NUM> and the controller <NUM>. By way of example, the operator I/O device <NUM> may include, but is not limited to, an interactive display, a touchscreen device, one or more buttons and switches, voice command receivers, and the like. In one embodiment, the operator I/O device <NUM> includes a brake and an accelerator pedal which suggests the need to either end engine torque production with a stop feature (e.g., pressing the brake pedal such that the vehicle <NUM> comes to a stop, etc.) or resume engine torque production with a start feature (e.g., pressing the accelerator pedal from a stopped state, in response to a restart command, shifting from a park mode into a drive mode, etc.).

As the components of <FIG> are shown to be embodied in the vehicle <NUM>, the controller <NUM> may be structured as an electronic control module (ECM). The ECM may include a transmission control unit and any other vehicle control unit (e.g., exhaust aftertreatment control unit, powertrain control module, engine control module, etc.). The function and structure of the controller <NUM> is described in greater detail in <FIG>.

Referring now to <FIG>, a schematic diagram of the controller <NUM> of the vehicle of <FIG> is shown according to an example embodiment, including functional and structural components. As shown in <FIG>, the controller <NUM> includes a processing circuit <NUM> including a processor <NUM> and a memory <NUM>. The processor <NUM> may be implemented as a general-purpose processor, an application specific integrated circuit (ASIC), one or more field programmable gate arrays (FPGAs), a digital signal processor (DSP), a group of processing components, or other suitable electronic processing components. The one or more memory devices <NUM> (e.g., RAM, ROM, Flash Memory, hard disk storage, etc.) may store data and/or computer code for facilitating the various processes described herein. The one or more memory devices <NUM> may be communicably connected to the processor <NUM> and provide computer code or instructions to the processor <NUM> for executing the processes described in regard to the controller <NUM> herein. Moreover, the one or more memory devices <NUM> may be or include tangible, non-transient volatile memory or non-volatile memory. The one or more memory devices <NUM> may include database components, object code components, script components, or any other type of information structure for supporting the various activities and information structures described herein.

The memory <NUM> is shown to include various modules for performing the activities described herein. More particularly, as shown in <FIG>, the memory <NUM> includes an engine module <NUM>, an aftertreatment system module <NUM>, a battery module <NUM>, and a stop/start module <NUM>. The various modules of the memory <NUM> are configured to determine whether to implement the stop/start feature based on an actual stop ratio being less than a target stop ratio at the beginning of an operating event (e.g., a driving event, etc.) and based on various operating conditions indicating that an inhibiting condition is not activated. While various modules with particular functionality are shown in <FIG>, it will be understood that the controller <NUM> and memory <NUM> may include any number of modules for performing the functions described herein. For example, the activities of multiple modules may be combined as a single module, additional modules with additional functionality may be included, etc. Further, it should be understood that the controller <NUM> may control other vehicle activity beyond the scope of the present disclosure.

Certain operations of the controller <NUM> described herein include operations to interpret and/or to determine one or more parameters. Interpreting or determining, as utilized herein, includes receiving values by any method known in the art, including at least receiving values from a datalink or network communication, receiving an electronic signal (e.g. a voltage, frequency, current, or PWM signal) indicative of the value, receiving a computer generated parameter indicative of the value, reading the value from a memory location on a non-transient computer readable storage medium, receiving the value as a run-time parameter by any means known in the art, and/or by receiving a value by which the interpreted parameter can be calculated, and/or by referencing a default value that is interpreted to be the parameter value.

As shown in <FIG>, the engine module <NUM> is in operative communication with the engine <NUM>. The engine module <NUM> is structured to interpret engine operation data indicative of an operating characteristic of the engine <NUM>. In one embodiment, as shown in <FIG>, the engine module <NUM> is structured to receive and interpret engine temperature data <NUM> indicative of an operating temperature of the engine <NUM> acquired by one or one or more sensors (e.g., sensors <NUM>). Therefore, the engine module <NUM> may be communicably coupled to a temperature sensor of the engine <NUM>. The engine temperature data <NUM> may be used to determine whether the engine temperature (e.g., temperature of the engine block, temperature of engine oil, etc.) has stabilized at a warm-up temperature (e.g., a standard operating temperature, above a minimum engine temperature threshold, etc.) following an engine warm up period (e.g., after a cold start of the engine <NUM>, to reduce engine friction during stop/start events, etc.).

In another embodiment, the engine module <NUM> is structured to determine whether the engine temperature has stabilized above a minimum engine temperature threshold based on a total engine run time since starting the engine <NUM>. For example, the controller <NUM> via the engine module <NUM> may determine the engine temperature (e.g., via algorithms, estimations, look-up tables, etc.) based on the run time of the engine <NUM> and other internal/external characteristics (e.g., ambient temperature, engine speed, power output, etc.).

In one embodiment, the engine module <NUM> is structured to determine engine friction characteristics based on engine oil temperature to determine whether engine friction is less than an engine friction threshold, thereby facilitating a substantially easy engine restart after implementing the stop/start feature (e.g., requiring a low torque input required to start the engine <NUM>, etc.). As such, the implementation of the stop/start feature may be based on the engine oil temperature. In one embodiment, the sensors <NUM> include an engine oil temperature sensor. In one embodiment, the engine oil temperature sensor may be configured to acquire data regarding the temperature of the engine oil. The viscosity of the engine oil, and thus the engine friction, is dependent on the temperature of the engine oil. Accordingly, the engine oil temperature may be used to provide an indication of the engine friction amount. In one embodiment, for example, a temperature of the engine oil that is substantially warm or hot correlates to the engine oil currently having a low viscosity, thereby indicating an engine friction low enough to implement the stop/start feature. The engine module <NUM> may be structured implement the stop/start feature based on any number of temperature measurement methods. For example, the engine module may be structured to implement the stop/start feature based on an engine coolant temperature, engine block temperature, engine head temperature, and/or engine manifold temperature. The start/stop feature may be implemented based on any direct or indirect temperature measurement device, including temperate measurement devices that can correlate with reduced engine start-up friction and normal combustion efficiency and emissions control.

In other embodiments, an engine oil temperature sensor may not be included. In one embodiment, the rotational friction of the engine <NUM> is determined by the amount of fueling required to idle the engine <NUM> at a constant speed (e.g., with an engine fuel gauge, etc.), which may indicate engine oil viscosity. The engine friction is then able to be determined based on the engine oil viscosity (e.g., via algorithms, estimations, look-up tables, etc.). In another embodiment, the engine <NUM> includes a positive displacement oil pump and an engine oil pressure sensor. The engine oil pressure sensor may be configured to acquire data regarding the pressure of the engine oil. With the positive displacement oil pump, the engine oil pressure becomes a function of pump speed (i.e., engine speed, etc.) and engine oil viscosity, providing an indication of engine friction. For example, warm or hot engine oil (i.e., oil with a low viscosity, etc.) may have a characteristically low engine oil pressure for a given engine speed. The engine friction may be determined by the controller <NUM> via the engine module <NUM> based on the engine oil pressure (e.g., via algorithms, estimations, look-up tables, etc.).

In some embodiments, the engine module <NUM> is further structured to receive and interpret the engine temperature data <NUM> to determine whether the engine temperature has stabilized at a temperature that is not excessively hot (e.g., the engine temperature is less than a maximum engine temperature threshold, etc.). For example, implementing the stop/start feature may cause engine damage through heat soak-back if the engine temperature is substantially high. In one embodiment, the engine temperature is compared to a maximum engine temperature threshold to determine whether the engine temperature exceeds the maximum engine temperature threshold. In some embodiments, for the stop/start feature to be implemented, the engine temperature lies within an engine operating temperature range (e.g., between the minimum engine temperature threshold and the maximum engine temperature threshold, etc.). As such, the implementation of the stop/start feature may be based on the engine temperature or the temperature of specific engine components (e.g., compression chamber, starter system, pistons, piston engine valves, etc.). In some embodiments, the implementation of the stop/start feature is based on the engine temperature of the engine <NUM> exceeding the minimum engine temperature threshold. In some embodiments, the implementation of the stop/start feature is based on the maximum engine temperature threshold exceeding the engine temperature. In some embodiments, the implementation of the stop/start feature is based on the engine temperature of the engine <NUM> exceeding the minimum engine temperature threshold, and based on the maximum engine temperature threshold exceeding the engine temperature.

In some embodiments, the engine module <NUM> is structured to determine whether the engine temperature has stabilized below the maximum engine temperature threshold (e.g., via algorithms, estimations, look-up tables, etc.) based on a total engine run time of the engine <NUM> since dropping below a threshold power level. For example, the engine <NUM> may be run at a high power output above the threshold power level for a duration of time such that the engine temperature exceeds the maximum engine temperature threshold. This may prohibit the stop/start feature from being implemented in order to prevent damage to the engine <NUM> (e.g., from heat-soak, etc.). As such, based on the total run time of the engine <NUM> below the threshold power level, the engine temperature may stabilize below the maximum engine temperature threshold, facilitating the implementation of the stop/start feature (e.g., if other inhibiting conditions are not present or activated, etc.).

As shown in <FIG>, the aftertreatment system module <NUM> may be in operative communication with the exhaust aftertreatment system <NUM> that may be coupled to the engine <NUM> (i.e., the exhaust aftertreatment system <NUM> receives exhaust gas from the engine <NUM>, etc.). The aftertreatment system module <NUM> is structured to interpret exhaust aftertreatment operation data indicative of an operating characteristic of the exhaust aftertreatment system <NUM>. In one embodiment, as shown in <FIG>, the aftertreatment system module <NUM> is structured to receive and interpret aftertreatment temperature data <NUM> indicative of a temperature of the exhaust aftertreatment system <NUM> and/or exhaust gas acquired by one or one or more sensors such as sensors <NUM>. In one embodiment, the sensors <NUM> include an exhaust aftertreatment temperature sensor configured to acquire the aftertreatment temperature data <NUM> regarding the temperature of the exhaust aftertreatment system <NUM> (e.g., DPF inlet, SCR, etc.) and/or the exhaust gas.

The aftertreatment temperature data <NUM> may be compared to an exhaust aftertreatment temperature threshold to determine whether the exhaust aftertreatment temperature is sufficient (e.g., above the exhaust aftertreatment temperature threshold, etc.) to support required chemical reactions (e.g., to reduce emissions, etc.). In one embodiment, for example, many engine operating points are set to be in compliance with one or more vehicular laws (e.g., emissions, etc.). However, during a warm-up period, the engine <NUM> may experience its highest temperature transients, and certain emissions control devices, such as the exhaust aftertreatment system <NUM>, may therefore perform sub-optimally (e.g., do not always comply with the emission regulations, etc.). By stopping the engine <NUM> during the warm-up period, the vehicle <NUM> may operate in a state of non-compliance with the one or more vehicular laws for a longer period of time during subsequent start-ups. As such, in some embodiments, the implementation of the stop/start feature may be based on the exhaust aftertreatment temperature exceeding the exhaust aftertreatment temperature threshold. For example, a low exhaust temperature may indicate that the exhaust aftertreatment system <NUM> is not operating at a desired temperature, and may thereby prevent the implementation of the stop/start feature (e.g., activating an inhibiting condition, etc.).

As shown in <FIG>, the battery module <NUM> may be in operative communication with the battery system <NUM> be coupled to the engine <NUM> (i.e., the battery system <NUM> powers various electronic components of the engine <NUM>, etc.). The battery module <NUM> is structured to interpret battery operation data indicative of an operating characteristic of the battery system <NUM>. In one embodiment, as shown in <FIG>, the battery module <NUM> is structured to receive and interpret energy data <NUM> indicative of a charge level of the battery system <NUM> (e.g., acquired by one or one or more sensors <NUM>, etc.). The energy data <NUM> may be compared to a charge threshold to determine whether the battery system has sufficient stored energy (e.g., above the charge threshold, etc.) to support a restart of the engine <NUM> after a stop command (e.g., automatically turning off the engine <NUM> in response to a stopping event, etc.). As such, in some embodiments, the implementation of the stop/start feature may be based on the charge level of the battery system <NUM> exceeding the charge threshold. For example, a low energy storage may indicate that the battery system <NUM> may not support an engine restart, which may then prevent the implementation of the stop/start feature (e.g., activating an inhibiting condition, etc.).

As shown in <FIG>, the stop/start module <NUM> may be operatively coupled to the engine <NUM>, the engine module <NUM>, the aftertreatment system module <NUM>, and/or the battery module <NUM>, among other modules and components. The stop/start module <NUM> is structured to interpret vehicle operation data indicative of operating characteristics of the vehicle <NUM>, the engine <NUM>, the exhaust aftertreatment system <NUM>, the battery system <NUM>, and the like. The stop/start module <NUM> is further structured to enable the stop/start feature of the engine <NUM> (e.g., permit shutting off the engine <NUM> is response to a stopping event, etc.) or disable the stop/start feature of the engine <NUM> (e.g., inhibit shutting off the engine <NUM> is response to a stopping event, etc.) based on the operation data (e.g., the charge level of the battery system <NUM>, the temperature of the exhaust aftertreatment system <NUM>, the operating temperature of the engine <NUM>, an actual stop ratio, a distance traveled and speed between subsequent stopping events, etc.) and various operating parameters (e.g., the charge threshold, the operating temperature range of the engine <NUM>, the exhaust aftertreatment system temperature threshold, a target/predetermined stop ratio, a distance threshold, a speed threshold, etc.). When the stop/start feature is enabled, the stop/start module <NUM> is structured to turn off the engine <NUM> for at least a portion of time in response to the vehicle <NUM> experiencing a stopping event (e.g., the vehicle <NUM> coming to a stop at a red light, a stop sign, etc.). Conversely, the stop/start module <NUM> is structured to inhibit the engine <NUM> from turning off in response to the vehicle <NUM> experiencing a stopping event when an inhibiting condition is present/activated based on the operation data indicating an operating parameter is not met.

As shown in <FIG>, the stop/start module <NUM> includes a ratio module <NUM> and an inhibiting module <NUM>. The ratio module <NUM> is structured to receive and interpret stopping data <NUM> indicative of a number of stops events the vehicle experiences (e.g., in response to an operator actuating a brake pedal, etc.). The stopping data <NUM> may also indicate a number of times the engine <NUM> has been turned off in response to the stopping events. The stopping data <NUM> may also indicate a total distance traveled by the vehicle <NUM> and the engine <NUM>, and/or a number of hours of operation of the engine <NUM>. The ratio module <NUM> is further structured to determine an actual stop ratio (e.g., a cumulative number of engine stops per hour of operation or distance traveled, etc.) for the engine <NUM>. The actual stop ratio may be based on at least one of a number of times the engine <NUM> is turned off in response to the occurrence of stopping events, and any of a number of measures related to the useful life or wear and tear on the engine such as the distance traveled (e.g., miles, kilometers, etc.) by the vehicle <NUM> and/or engine <NUM>, a number of hours since the purchase date of the engine <NUM>, and a number of hours of operation of the engine <NUM>. The actual stop ratio indicates a number of times the engine <NUM> is turned off in response to a stopping event for a total distance traveled or a total number of hours of operation of the engine <NUM> over the engine's lifetime. For example, the vehicle <NUM> may have been driven for <NUM>,<NUM> miles and over the <NUM>,<NUM> miles the stop/start module <NUM> turned off the engine <NUM> in response to a stopping event <NUM>,<NUM> times. Therefore, in this example, the actual stop ratio for the engine <NUM> is <NUM>:<NUM> (i.e., the engine <NUM> is turned off approximately every <NUM> miles).

The ratio module <NUM> is structured to compare the actual stop ratio to a target stop ratio. In one embodiment, the target stop ratio is predefined within the controller <NUM>. In an alternative embodiment, an operator may provide the target stop ratio via the operator I/O device <NUM>. In one embodiment, the target stop ratio is based on at least one of an expected life of the engine <NUM> (e.g., <NUM> years, <NUM> years, <NUM> years, etc.), an expected life of the engine <NUM> in distance traveled (e.g., <NUM>,<NUM> miles; <NUM>,<NUM> kilometers; etc.), and an expected life of the engine <NUM> in hours (e.g., <NUM>,<NUM> hours; <NUM>,<NUM> hours; etc.). In some embodiments, the target stop ratio is based on at least one of a term of a warranty (e.g., <NUM> years, <NUM> years, <NUM> years, etc.), a distance traveled covered by the warranty (e.g., <NUM>,<NUM> miles; <NUM>,<NUM> miles; <NUM>,<NUM> kilometers; etc.), a number of hours of calendar time covered by the warranty, and a number of hours of engine run time covered by the warranty (e.g., <NUM>,<NUM> hours; <NUM>,<NUM> hours; <NUM>,<NUM> hours; etc.). The target stop ratio may also be based on a number of starts the engine <NUM> is designed for. For example, an engine may be designed to withstand <NUM>,<NUM> total starts. If the engine <NUM> is warrantied for <NUM>,<NUM> miles, the target stop ratio for the engine in this example is <NUM>:<NUM> (i.e., the engine <NUM> may be turned off an average of one time per mile).

The inhibiting module <NUM> is structured to determine whether an inhibiting condition needs to be activated to disable the stop/start feature of the engine <NUM>. A first inhibiting condition is based on the actual stop ratio being greater than the target stop ratio at a beginning of a driving event. According to an example embodiment, a driving event comprises a period defined by when the engine <NUM> is manually turned on by an operator to when the engine <NUM> is manually turned off by the operator. Manually turning on or turning off the engine <NUM> may include turning a key in an ignition, actuating a turn on/turn off button within the vehicle <NUM>, pressing a start/stop button on a key remote, and/or any other way the engine <NUM> may be turned on or off by an operator (i.e., not automatically by the controller <NUM> in response to a stopping event, etc.).

The first inhibiting condition is activated in response to the actual stop ratio for the engine <NUM> being greater than the target stop ratio at the beginning of the driving event. The first inhibiting condition remains activated until the actual stop ratio of the engine <NUM> becomes less than the target stop ratio. For example, the actual stop ratio may be <NUM>:<NUM> and the target stop ratio may be <NUM>:<NUM> at the beginning of the driving event. Therefore, the stop/start feature is disabled by the stop/start module <NUM> during the driving event until the actual stop ratio reduces to become less than <NUM>:<NUM>. If the actual stop ratio does not decease below the target stop ratio during the driving event, the stop/start module <NUM> disables the stop/start feature in each subsequent driving event until the actual stop ratio becomes less than the target stop ratio. However, the inhibiting module <NUM> is structured to not activate the first inhibiting condition in response the actual stop ratio increasing to be greater than the target stop ratio during a driving event if at the beginning of or if at any time during the driving event the actual stop ratio was less than the target stop ratio. Therefore, the stop/start module <NUM> is structured to keep the stop/start feature enabled during the driving event to maintain a consistent stop/start logic that does not cause the operator to believe the vehicle <NUM> may be operating improperly (e.g., by keeping the stop/start feature activated during a driving event where the stop/start feature may have already been implemented in response to a stopping event, the first inhibiting condition may be activated in a subsequent driving event if the actual stop ratio is greater than the target stop ratio at the end of a prior driving event, etc.).

A second inhibiting condition is based on the charge level of the battery system <NUM> being less than the charge threshold. For example, the battery system <NUM> may be depleted to an energy level below the charge threshold such that the battery system <NUM> cannot facilitate the restarting of the engine <NUM>. Therefore, the stop/start module <NUM> may disable the stop/start feature until the battery system <NUM> charges to a level above the charge threshold. Thus, the second inhibiting event may be activated when the charge level of the battery system <NUM> is below the charge threshold.

A third inhibiting condition is based on the operating temperature of the engine <NUM> being outside of the operating temperature range (e.g., below the minimum engine temperature threshold, above the maximum engine temperature threshold, etc.). By way of example, when the engine temperature is below the minimum engine temperature threshold (e.g., during a warm-up period, etc.), engine friction increases which thereby increases the torque and electrical energy required to restart the engine <NUM> after the stop/start feature is implemented. Thus, the third inhibiting condition may be activated when the temperature of the engine <NUM> is below the minimum engine temperature threshold. By way of another example, when the engine temperature is above the maximum engine temperature threshold, shutting the engine <NUM> off during a stopping event may cause damage to various component of the engine <NUM> through heat soak. Thus, the third inhibiting condition may be activated when the temperature of the engine <NUM> is above the maximum engine temperature threshold.

A fourth inhibiting condition is based on the operating temperature of the exhaust aftertreatment system <NUM> being less than the exhaust aftertreatment system temperature threshold. For example, during a warm up period of the engine <NUM>, the components of the exhaust aftertreatment system <NUM> may be at an operating temperature such that the exhaust aftertreatment system <NUM> may not comply with emission regulations. Therefore, allowing the engine <NUM> to turn off would further delay the exhaust aftertreatment system <NUM> from reaching an appropriate operating temperature. Thus, the fourth inhibiting condition may be activated when the temperature of the exhaust aftertreatment system is below the exhaust aftertreatment temperature threshold.

In some embodiments, the stop/start module <NUM> is structured to receive and interpret speed data <NUM> indicative of a maximum speed of the vehicle <NUM> between stopping events. A fifth inhibiting condition is based on the maximum speed of the vehicle <NUM> between stopping events being less than a speed threshold. The inhibiting module <NUM> may monitor the speed between stopping events to determine whether the vehicle <NUM> is in a traffic jam like condition or whether the operator is driving as such a condition exists (e.g., stop-and-go, etc.) such that the stop/start module <NUM> does not turn off the engine <NUM> when the vehicle <NUM> travels at a substantially slow speed (e.g., <NUM> miles per hour, <NUM> kilometers per hour, etc.). Thus, the fifth inhibiting event may be activated when the vehicle <NUM> operates when a maximum speed between stopping events is less than the speed threshold.

In additional embodiments, the stop/start module <NUM> is structured to receive and interpret distance data <NUM> indicative of a distance traveled between stopping events. A sixth inhibiting condition is based on the distance the vehicle <NUM> travels between stopping events being less than a distance threshold. The inhibiting module <NUM> may monitor the distance between stopping events to determine whether the vehicle <NUM> may be in a traffic jam like condition or whether the operator is driving as such a condition exists (e.g., stop and go, etc.) such that the stop/start module <NUM> does not turn off the engine <NUM> when the vehicle <NUM> travels a substantially small distance (e.g., <NUM> feet, <NUM> feet, etc.) before stopping. Thus, the sixth inhibiting event may be activated when the distance between two consecutive stopping events is less than the distance threshold.

The inhibiting module <NUM> is structured to activate one or more of the aforementioned inhibiting conditions. It should be understood that the inhibiting module <NUM> may be structured to activate an inhibiting condition based on other factors than described above. The inhibiting conditions may be activated at the beginning of a driving event (i.e., during an engine warm up period, an aftertreatment system warm up period, etc.) and deactivated once the engine <NUM> reaches typical operating conditions (e.g., engine operating temperature, exhaust aftertreatment system operating temperature, etc.). For example, when the actual stop ratio is greater than the target ratio at the beginning of the driving event, the first inhibiting condition may be activated along with the third and fourth inhibiting conditions (e.g., if the engine <NUM> starts from a cold start at the beginning of a driving event, etc.). When the engine <NUM> and the exhaust aftertreatment system <NUM> reach operating temperatures, the third and fourth inhibiting conditions may be deactivated. The first inhibiting condition remains active until the actual stop ratio decreases to less than the target stop ratio. Therefore, if the actual stop ratio remains above the target stop ratio following the warm up period of the engine <NUM> and the exhaust aftertreatment system <NUM>, the stop/start feature remains disabled until the first inhibiting condition can be deactivated in response to the actual stop ratio decreasing below the target stop ratio, thereby increasing the "warm-up period" of the engine <NUM>. Extending the warm-up period of the engine to inhibit automatically stopping and restarting the engine may provide an operator of the vehicle with an impression that the stop/start logic is consistent and is working properly.

Referring now to <FIG>, a method <NUM> of managing automatic stop/start frequency of an engine is shown according to an example embodiment. In one example embodiment, method <NUM> may be implemented with the controller <NUM> and the various modules of <FIG>. As such, method <NUM> may be described with regard to <FIG>.

At process <NUM>, a driving event is initiated in response to an engine (e.g., the engine <NUM>, etc.) being manually turned on (e.g., with a key, push start, etc.) by an operator. At process <NUM>, the controller <NUM> determines an actual stop ratio for the engine at the start of the driving event. At process <NUM>, the controller <NUM> determines whether the actual stop ratio is greater than a target stop ratio. If the actual stop ratio is less than the target stop ratio, the controller <NUM> enables a stop/start feature (process <NUM>). Conversely, if the actual stop ratio is greater than the target stop ratio, the controller <NUM> disables the stop/start feature (process <NUM>).

If the stop/start feature is enabled at the beginning of the driving event (process <NUM>), the actual stop ratio does not affect the application of the stop/start feature until subsequent driving events (e.g., if the actual stop ratio becomes greater than the target stop ratio during the first driving event, the stop/start feature is not disabled until a second driving event, etc.). Therefore, the actual stop ratio may increase above the target stop ratio during a driving event without affecting the stop/start feature for the current driving event. At process <NUM>, the engine experiences a stopping event (e.g., a vehicle comes to a red light, a stop sign, the operator presses a brake pedal till the vehicle comes to a rest, etc.). At process <NUM>, the controller <NUM> determines whether an inhibiting condition is present (e.g., the charge level of the battery system <NUM> being less than the charge threshold, the operating temperature of the engine <NUM> being outside of the operating temperature range, the operating temperature of the exhaust aftertreatment system <NUM> being less than the exhaust aftertreatment system temperature threshold, the maximum speed of the vehicle <NUM> between stopping events being less than a speed threshold, the distance the vehicle <NUM> travels between stopping events being less than a distance threshold, etc.). If an inhibiting condition is present, the controller <NUM> keeps the engine running and returns to process <NUM> where the controller <NUM> waits for the engine to experience another stopping event. The controller <NUM> then repeats process <NUM> to determine if the same or another inhibiting condition is present during the subsequent stopping event.

If an inhibiting condition is not present, the controller <NUM> turns off the engine for at least a portion of time (process <NUM>). At process <NUM>, the controller <NUM> determines whether the engine is manually turned off by an operator during the stopping event. If the engine is not manually turned off and the controller <NUM> receives a restart command (e.g., from an operator pressing an accelerator pedal, putting the vehicle in drive, etc.), the controller <NUM> restarts the engine responsive to the restart command (process <NUM>). The controller <NUM> then repeats processes <NUM>-<NUM> until the engine is manually turned off during a stopping event, at which time the controller <NUM> ends the driving event (process <NUM>).

If the stop/start feature is disabled at the beginning of the driving event (process <NUM>), the actual stop ratio affects the application of the stop/start feature during the current driving event (and potentially subsequent driving events). At process <NUM>, the engine experiences a stopping event. At process <NUM>, the controller <NUM> determines the actual stop ratio for the engine in response to the stopping event. At process <NUM>, the controller <NUM> determines whether the actual stop ratio is greater than the target stop ratio. If the actual stop ratio is less than the target stop ratio, the controller <NUM> enables the stop/start feature (process <NUM>) and continues onto process <NUM>. Conversely, if the actual stop ratio is still greater than the target stop ratio, the controller <NUM> keeps the stop/start feature disabled and the controller <NUM> returns to process <NUM> where the controller <NUM> waits for the engine to experience another stopping event and then repeats processes <NUM>-<NUM>.

Referring now to <FIG> and <FIG>, method <NUM> and method <NUM> for managing automatic stop/start frequency of an engine are shown according to additional example embodiments. In some example embodiment, method <NUM> and method <NUM> may be implemented with the controller <NUM> and the various modules of <FIG>. In some example embodiments, certain steps of method <NUM> and method <NUM> may be implemented similar to method <NUM>. As such, method <NUM> and method <NUM> are described with regard to <FIG> and method <NUM>.

Referring specifically now to <FIG>, method <NUM> includes each process of <FIG> in addition to process <NUM>. In method <NUM>, if the controller <NUM> determines that the actual stop ratio is not greater than a target stop ratio at process <NUM>, the controller <NUM> enables a stop/start feature at process <NUM>. At process <NUM>, if the controller <NUM> determines that the actual stop ratio is greater than a target stop ratio at process <NUM>, the controller <NUM> determines whether other inhibiting conditions are present at step <NUM>. If other inhibiting conditions are determined to not be present at step <NUM>, the controller <NUM> enables a stop/start feature at process <NUM>. Conversely, if other inhibiting conditions are determined to be present at step <NUM>, the controller <NUM> disables the stop/start feature at process <NUM>. For example, in one embodiment, if the controller <NUM> determines that the actual stop ratio is greater than a target stop ratio and that the engine is in an engine warm up period (i.e., another inhibiting condition is present), the controller <NUM> disables the stop/start feature.

Referring specifically now to <FIG>, method <NUM> includes each process of <FIG> in addition to process <NUM> and process <NUM>. In method <NUM>, the controller <NUM> determines whether the actual stop ratio is greater than the target stop ratio at process <NUM>. If the actual stop ratio is less than the target stop ratio, the controller <NUM> enables the stop/start feature at process <NUM> and continues onto process <NUM>. Conversely, if the actual stop ratio is greater than the target stop ratio at process <NUM>, the controller <NUM> implements an increment stop ratio timer at process <NUM> and returns to process <NUM> where the controller <NUM> waits for the engine to experience another stopping event. After experiencing another stopping event, the controller <NUM> again determines the actual stop ratio for the engine in response to the stopping event at process <NUM>. Next, at process <NUM>, the controller <NUM> determines whether the stop ratio timer has timed out. If the stop ratio timer has not timed out, the controller <NUM> again determines whether the actual stop ratio is greater than the target stop ratio at process <NUM>. Conversely, if the stop ratio timer has timed out, the controller <NUM> continues onto process <NUM>. For example, the stop ratio timer may delay the controller <NUM> from carrying out the rest of method <NUM> for the duration of a time period or may limit the inhibiting of the stop/start feature to a maximum time period. In some embodiments, the duration of the time period may be based on at least one of a magnitude of the difference between the actual stop ratio and the target stop ratio, an engine operation parameter, at least one term of a warranty, a time between stopping events, and any number of other criteria.

The schematic flow chart diagrams and method schematic diagrams described above are generally set forth as logical flow chart diagrams. As such, the depicted order and labeled steps are indicative of representative embodiments. Other steps, orderings and methods may be conceived that are equivalent in function, logic, or effect to one or more steps, or portions thereof, of the methods illustrated in the schematic diagrams.

Additionally, the format and symbols employed are provided to explain the logical steps of the schematic diagrams and are understood not to limit the scope of the methods illustrated by the diagrams. Although various arrow types and line types may be employed in the schematic diagrams, they are understood not to limit the scope of the corresponding methods. Indeed, some arrows or other connectors may be used to indicate only the logical flow of a method. For instance, an arrow may indicate a waiting or monitoring period of unspecified duration between enumerated steps of a depicted method. Additionally, the order in which a particular method occurs may or may not strictly adhere to the order of the corresponding steps shown. It will also be noted that each block of the block diagrams and/or flowchart diagrams, and combinations of blocks in the block diagrams and/or flowchart diagrams, can be implemented by special purpose hardware-based systems that perform the specified functions or acts, or combinations of special purpose hardware and program code.

Many of the functional units described in this specification have been labeled as modules, in order to more particularly emphasize their implementation independence. For example, a module may be implemented as a hardware circuit comprising custom VLSI circuits or gate arrays, off-the-shelf semiconductors such as logic chips, transistors, or other discrete components.

Modules may also be implemented in machine-readable medium for execution by various types of processors. An identified module of executable code may, for instance, comprise one or more physical or logical blocks of computer instructions, which may, for instance, be organized as an object, procedure, or function. Nevertheless, the executables of an identified module need not be physically located together, but may comprise disparate instructions stored in different locations which, when joined logically together, comprise the module and achieve the stated purpose for the module.

Indeed, a module of computer readable program code may be a single instruction, or many instructions, and may even be distributed over several different code segments, among different programs, and across several memory devices. The operational data may be collected as a single data set, or may be distributed over different locations including over different storage devices, and may exist, at least partially, merely as electronic signals on a system or network. Where a module or portions of a module are implemented in machine-readable medium (or computer-readable medium), the computer readable program code may be stored and/or propagated on in one or more computer readable medium(s).

The computer readable medium may be a tangible computer readable storage medium storing the computer readable program code. The computer readable storage medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, holographic, micromechanical, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing.

More specific examples of the computer readable medium may include but are not limited to a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), a portable compact disc read-only memory (CD-ROM), a digital versatile disc (DVD), an optical storage device, a magnetic storage device, a holographic storage medium, a micromechanical storage device, or any suitable combination of the foregoing. In the context of this document, a computer readable storage medium may be any tangible medium that can contain, and/or store computer readable program code for use by and/or in connection with an instruction execution system, apparatus, or device.

The computer readable medium may also be a computer readable signal medium. Such a propagated signal may take any of a variety of forms, including, but not limited to, electrical, electro-magnetic, magnetic, optical, or any suitable combination thereof. A computer readable signal medium may be any computer readable medium that is not a computer readable storage medium and that can communicate, propagate, or transport computer readable program code for use by or in connection with an instruction execution system, apparatus, or device. Computer readable program code embodied on a computer readable signal medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, Radio Frequency (RF), or the like, or any suitable combination of the foregoing.

In one embodiment, the computer readable medium may comprise a combination of one or more computer readable storage mediums and one or more computer readable signal mediums. For example, computer readable program code may be both propagated as an electro-magnetic signal through a fiber optic cable for execution by a processor and stored on RAM storage device for execution by the processor.

Computer readable program code for carrying out operations for aspects of the present invention may be written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The computer readable program code may execute entirely on the user's computer, partly on the user's computer, as a stand-alone computer-readable package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server.

The program code may also be stored in a computer readable medium that can direct a computer, other programmable data processing apparatus, or other devices to function in a particular manner, such that the instructions stored in the computer readable medium produce an article of manufacture including instructions which implement the function/act specified in the schematic flowchart diagrams and/or schematic block diagrams block or blocks.

Claim 1:
An apparatus for managing automatic stop/start frequency of an engine, comprising:
a stop/start module in operative communication with an engine, the stop/start module comprising:
means for determining whether a stopping event has occurred;
means for determining whether an inhibiting condition is activated;
means for turning off the engine for at least a portion of time in response to determining that a stopping event has occurred if the inhibiting condition is not activated;
a ratio module configured to determine an actual stop ratio for the engine based on a number of times the engine is turned off in response to determining the occurrences of stopping events;
means for determining a target stop ratio based on an operating parameter; and
an inhibiting module configured to activate the inhibiting condition based on the actual stop ratio for the engine being greater than the target stop ratio, thereby inhibiting automatically turning off the engine, wherein the inhibiting condition remains activated during a driving event until the actual stop ratio of the engine becomes less than the target stop ratio, wherein a driving event commences when the engine is manually turned on by an operator and ends when the engine is manually turned off by the operator;
the apparatus being characterised in that the activation of the inhibiting condition occurs only at a beginning of the driving event.