JP4843597B2 - Control device for internal combustion engine - Google Patents

Description

  The present invention relates to an internal combustion engine control apparatus, and more specifically, an internal combustion engine control apparatus that controls the operation of an actuator that drives a throttle valve disposed in an intake pipe of an internal combustion engine mounted on a vehicle such as a motorcycle. About.

  In recent years, a DBW (Drive By Wire) type internal combustion engine control device is known in which a mechanical connection between a throttle valve and an accelerator is cut off and the throttle valve is driven by an actuator. Such an apparatus generally includes a throttle opening sensor that generates an output indicating the opening of the throttle valve, and is configured to drive the throttle valve based on the output. For this reason, there is a difference between the output indicating the fully closed position and the fully opened position in the throttle opening sensor and the actual fully closed position and fully opened position of the throttle valve due to variations in the position where the throttle opening sensor is attached. In this case, there arises a problem that the throttle valve cannot be set to a desired throttle opening.

  Therefore, as a technique for accurately detecting the throttle opening sensor output reference values (fully closed reference value and fully open reference value) corresponding to the actual throttle valve fully closed position and fully open position, the throttle valve is fully closed and fully opened. A technique has been proposed in which the output is forcibly driven to a position and the output of the throttle opening sensor at that time is determined as a fully closed and fully opened reference value (see, for example, Patent Document 1). However, when configured as in the technique described in Patent Document 1, for example, when each reference value is determined when the internal combustion engine is started, the time required for the determination increases by the time for driving the throttle valve, and as a result, the internal combustion engine Inconvenience that the startability of the is reduced.

As a technique for solving such inconvenience, in Patent Document 2 below, the throttle valve is forcibly driven to the fully closed position when the ignition is off, and the output of the throttle opening sensor is set to the fully closed reference candidate value (fully closed). When the internal combustion engine is started next time, specifically, a predetermined value is subtracted from the output of the throttle opening sensor when the ignition is turned on to calculate a fully closed reference estimated value, and the calculated fully closed reference When the difference between the estimated value and the fully closed reference candidate value is less than the allowable value, the fully closed reference candidate value is used as the fully closed reference value, that is, the throttle valve is driven to the fully closed position when starting the internal combustion engine. Without being configured, it is configured to determine the fully closed reference value. When the difference is equal to or larger than the allowable value, the throttle valve is driven to the fully closed position, and the fully closed reference value is relearned.
JP-A-10-169470 JP 2003-227359 A

  By the way, the output of the throttle opening sensor is easily influenced by the ambient temperature. That is, the temperature environment of the throttle opening sensor differs between when the ignition is off and when it is on. Specifically, if the temperature environment changes according to the operating conditions such as cold start or warm start, depending on the temperature characteristics of the sensor Deviation occurs in sensor output.

  Therefore, as in the technique described in Patent Document 2, when the sensor output at the time of ignition off is used as a fully closed reference candidate value, the total closed reference estimation value is calculated based on the sensor output at the time of ignition on, The closed reference estimated value cannot be calculated accurately, and as a result, the relearning of the fully closed reference value (specifically, the operation for forcibly driving the throttle valve to the fully closed position) may be frequently performed. . In addition, since the throttle valve is driven to the fully closed position every time the ignition is turned off, there is a problem that the power consumption increases.

  Accordingly, the object of the present invention is to solve the above-mentioned problems, and to accurately and quickly determine the full-close reference value of the throttle opening sensor corresponding to the full-close position of the throttle valve, and to reduce power consumption. An object of the present invention is to provide a control device for an internal combustion engine.

In order to solve the above-mentioned object, according to a first aspect of the present invention, there is provided a control device for an internal combustion engine that controls the operation of an actuator that drives a throttle valve disposed in an intake pipe of the internal combustion engine. A throttle opening sensor that generates an output indicating the output of the throttle opening sensor that corresponds to the position of the throttle valve when not driven by the actuator is determined as an initial reference value, and is determined from the determined initial reference value A fully closed reference estimated value determining means for determining a value obtained by subtracting a predetermined value of 1 as a fully closed reference estimated value; and the throttle valve when the internal combustion engine is started is used as the determined fully closed reference estimated value. A comparison means for comparing with a fully closed reference candidate value corresponding to a fully closed position of the valve; The throttle opening sensor when the throttle valve is driven to the fully closed position by the actuator when the fully closed reference candidate value is determined as the fully closed reference value and the difference is greater than a second predetermined value. A fully closed reference value determining means for determining the output of the fully closed reference value, a fully open reference value determining means for determining a fully open reference value corresponding to the fully open position of the throttle valve based on at least the determined fully closed reference value , before SL so that the opening degree of the throttle valve becomes a target value determined within the range defined by the fully open reference value is fully closed reference value which is the determination, the actuator control means for controlling the operation of the actuator, and the When the difference between the fully closed reference estimated value and the fully closed reference candidate value is larger than the second predetermined value, the first predetermined value is changed from the initial reference value to the fully closed reference value. Was configured with a first predetermined value updating means for updating the value obtained by calculation.

According to claim 2 , the fully open reference value determining means is a fully open reference value corresponding to the fully open position of the throttle valve based on the characteristics of the throttle opening sensor obtained from the initial reference value and the fully closed reference value. Configured to determine.

  The control apparatus for an internal combustion engine according to claim 1 includes a throttle opening sensor that generates an output indicating the opening of the throttle valve, and the throttle opening sensor corresponding to the position of the throttle valve when not driven by the actuator. The output is determined as an initial reference value, and a value obtained by subtracting the first predetermined value from the determined initial reference value is determined as a fully closed reference estimated value, and the determined fully closed reference estimated value is A configuration is made to compare with a fully closed reference candidate value corresponding to the fully closed position of the throttle valve when the engine is started, that is, the fully closed reference estimated value is converted into a fully closed reference candidate value (in other words, at the start of the internal combustion engine). Then, the sensor output under the temperature environment that is substantially the same as the temperature environment (operating state) for which the fully closed reference estimated value is determined is compared with the previously stored fully closed reference candidate value). , Slot At the output of the torque opening sensor it can be less affected by differences in temperature environment. In addition, when the difference between the fully closed reference estimated value and the fully closed reference candidate value is equal to or smaller than the second predetermined value, the fully closed reference candidate value is determined as the fully closed reference value, that is, the difference is the second It is judged that the reliability of the fully closed reference candidate value is relatively high if it is below the predetermined value, and the fully closed reference candidate value is determined as the fully closed reference value without driving the throttle valve to the fully closed position. Therefore, the fully closed reference value can be determined accurately and quickly, and the power consumption can be reduced as compared with the technique described in Patent Document 2 in which the throttle valve is driven to the fully closed position each time the ignition is turned off. it can.

  When the difference is greater than a second predetermined value, the throttle opening sensor output when the throttle valve is driven to the fully closed position by the actuator is determined as the fully closed reference value, When the difference is larger than the second predetermined value, the reliability of the fully closed reference candidate value is judged to be relatively low, and only when that is the case, the fully closed reference value is determined by driving the throttle valve to the fully closed position. Therefore, the fully closed reference value can be determined more accurately.

  Further, a fully open reference value corresponding to the fully opened position of the throttle valve is determined based on at least the determined fully closed reference value, and the opening degree of the throttle valve is defined by the determined fully closed reference value and fully opened reference value. Since the operation of the actuator is controlled so as to be a target value determined within the range, for example, when the actual throttle valve reaches the fully closed position and is in contact with the fully closed end, the actuator is The throttle valve is not driven further in the closing direction, so that the load current of the actuator is increased, and there is no problem such as wasteful power consumption in the battery.

Further , when the difference between the fully closed reference estimated value and the fully closed reference candidate value is larger than the second predetermined value, in other words, the throttle valve is driven to the fully closed position by the actuator, and the throttle opening sensor at that time When the output is determined as the fully closed reference value, the first predetermined value is updated to a value obtained by subtracting the fully closed reference value from the initial reference value. The predetermined value can be set to a value corresponding to the newly determined fully closed reference value, and thus the fully closed reference estimated value obtained using the first predetermined value can be accurately determined.

In the control apparatus for an internal combustion engine according to claim 2 , the fully open reference value corresponding to the fully open position of the throttle valve is determined based on the characteristics of the throttle opening sensor obtained from the initial reference value and the fully closed reference value. In other words, the throttle valve is driven to the fully open position in addition to the above-described effect, because the throttle valve is not driven to the fully open position as in the technique described in Patent Document 1. The fully open reference value can be quickly determined by the amount of time to be used.

  The best mode of a control apparatus for an internal combustion engine according to the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a schematic diagram showing an overall control apparatus for an internal combustion engine according to an embodiment of the present invention.

  In FIG. 1, reference numeral 10 denotes a saddle-ride type vehicle, specifically a motorcycle. The motorcycle 10 is equipped with an internal combustion engine (hereinafter referred to as “engine”) 12 and a handlebar 14 attached above a telescopic fork (not shown) of the front wheel. The engine 12 is a four-cycle single-cylinder water-cooled type, and is composed of a gasoline engine having a displacement of about 250 cc, for example.

  On the right side of the handlebar 14 (as viewed from the driver), an accelerator 16, more precisely an accelerator 16 comprising a throttle grip, is provided for the driver's operation, and the front wheel brake lever 20 is also provided for the driver's operation. . The front wheel brake lever 20 is mechanically connected to a front wheel brake (both not shown) via a hydraulic cylinder, and when operated (gripped) by a driver, the front wheel brake is operated to brake the front wheel. Note that a grip and a clutch lever that can be gripped by the driver are provided on the left side of the handle bar 14, but they are not directly related to the subject matter of the present application, and thus illustration and description thereof are omitted.

  A throttle valve 24 is disposed in the intake pipe 22 (partially shown in FIG. 1) of the engine 12 to adjust the amount of air flowing through the intake pipe 22. A default spring or the like (not shown) is attached to the throttle valve 24. When the throttle valve 24 is not driven by an electric motor, which will be described later (for example, when the electric motor is in a non-energized state), the default opening (initial opening degree, full opening degree). The throttle valve 24 is energized so that the angle becomes approximately 3 degrees when the angle is approximately 90 degrees.

  An injector (not shown) is disposed downstream of the throttle valve 24 in the intake pipe 22, and gasoline fuel is injected into the intake air adjusted by the throttle valve 24. The injected fuel mixes with intake air to form an air-fuel mixture, and the air-fuel mixture flows into the combustion chamber 30 when the intake valve 26 opens.

  The air-fuel mixture flowing into the combustion chamber 30 is ignited and burned by spark discharge from the spark plug 32 with a high voltage supplied from an ignition coil (not shown), and the piston 34 is driven downward in FIG. Let me. When the exhaust valve 40 is opened, the exhaust gas generated by the combustion is discharged to the outside of the engine 12 through an exhaust pipe or a catalyst device (none of which is shown) that removes harmful components in the exhaust gas.

  As shown in FIG. 1, the throttle valve 24 is mechanically disconnected from the accelerator (throttle grip) 16. That is, the throttle valve 24 is connected to an electric motor (actuator) 44 through the reduction gear mechanism 42 and is driven (opened / closed) by the operation of the electric motor 44. Specifically, the electric motor 44 includes a three-phase brushless DC motor including a rotor (rotor) and a stator (stator). In this way, the throttle valve 24 is a DBW system driven by the electric motor 44.

  The electric motor 44 is provided with a hall sensor (hereinafter also referred to as “rotor position sensor”) 50 having a hall element attached in the vicinity of the rotor, and outputs a signal corresponding to the position of the rotor of the electric motor 44. To do. Further, a throttle opening sensor 52 comprising a variable resistance potentiometer is provided in the vicinity of the throttle valve 24, and an output indicating the opening of the throttle valve 24, specifically, between about 0 degrees and about 90 degrees. Output TPSAD [V] indicating the actual opening (hereinafter referred to as “actual throttle opening”). Note that the throttle opening sensor 52 is configured to have an output that is directly proportional to the output so that the output TPSAD increases as the opening of the throttle valve 24 increases.

  Similarly, an accelerator opening sensor 54 comprising a variable resistance potentiometer is provided in the vicinity of the accelerator 16, and an output APSAD [V] corresponding to the opening of the accelerator 16 (specifically, the rotation amount of the throttle grip) is provided. Arise. Note that the opening of the accelerator 16 is set so that the initial position corresponds to the throttle opening of about 0 degrees, and the maximum rotation corresponds to the throttle opening of about 90 degrees. Further, the accelerator opening sensor 54 outputs a voltage of a predetermined amount (for example, 0.7 [V]) when the accelerator 16 is in the initial position, that is, when the accelerator 16 is not operated, and the accelerator 16 rotates. The output APSAD is configured to increase as the amount increases.

  An intake pressure sensor (absolute pressure sensor) 56 is provided at an appropriate position of the intake pipe 22 to generate an output indicating the absolute pressure in the intake pipe (engine load). Further, a water temperature sensor 60 is attached to a cooling water passage (not shown) of the cylinder block of the engine 12 to generate an output corresponding to the temperature of the cooling water of the engine. A crank angle sensor 62 is attached in the vicinity of the crankshaft 36 of the engine 12 and outputs a pulse signal at every predetermined crank angle.

  The motorcycle 10 further includes an engine controller 64 that controls fuel injection of the engine 12 and the like, and a throttle valve controller 66 that controls the operation of the throttle valve 24 (more precisely, the electric motor 44). These controllers 64 and 66 are connected to a battery 72 via an ignition switch 70 and supplied with operating power.

  The engine controller 64 is electrically connected to the accelerator opening sensor 54 and the like, and detects a sensor output, and controls the operation of the injector based on the sensor output detected by the detection circuit. A microprocessor (hereinafter referred to as “MPU”) 64 a that outputs signals and the like is provided.

  More specifically, as shown in FIG. 1, the MPU 64a receives the output APSAD of the accelerator opening sensor 54 via the accelerator opening sensor output detection circuit 64b for A / D conversion, and the A / D conversion value. Is converted into a value corresponding to a value from about 0 degree to about 90 degrees in the throttle opening, that is, an accelerator opening APS (accelerator opening APS is calculated (detected)) according to appropriate characteristics.

  The output TPSAD of the throttle opening sensor 52 is input to the MPU 64a via the throttle opening sensor output detection circuit 64c and A / D conversion is performed, and the A / D conversion value is 0 of the throttle valve 24 according to appropriate characteristics. A value between about 90 degrees and about 90 degrees, that is, an actual throttle opening TPS is converted (the actual throttle opening TPS is calculated (detected)).

  Further, the output of the intake pressure sensor 56 is input to the MPU 64a via the intake pressure sensor output detection circuit 64d, and the output of the water temperature sensor 60 is input via the water temperature sensor output detection circuit 64e, respectively, for A / D conversion. Then, it is converted (calculated) into intake pressure PBA and water temperature (engine temperature) TW. Further, the output of the crank angle sensor 62 is input to the MPU 64a via the crank angle sensor output detection circuit 64f, and the output is counted to calculate the engine speed NE.

  When the ignition switch 70 is turned on by the driver, the battery 72 described above is connected to the battery voltage detection circuit 64h via a power supply circuit 64g that supplies operating power to the MPU 64a. The output of the battery voltage detection circuit 64h is also input to the MPU 64a. The MPU 64a determines whether or not the battery 72 can drive the electric motor 44 based on the output of the battery voltage detection circuit 64h or the like (for example, whether or not the voltage of the battery 72 is equal to or higher than a predetermined voltage). When it is determined that 44 can be driven, a permission signal is output.

  On the other hand, the throttle valve controller 66 includes an MPU 66 a that outputs a signal for controlling the operation of the electric motor 44 based on the output of the rotor position sensor 50 and the like. As shown in the figure, the MPU 66a is connected to the MPU 64a of the engine controller 64 so as to be able to communicate with each other via CAN (Controller Area Network) communication. Specifically, the output APSAD and throttle opening of the accelerator opening sensor 54 are connected. Signals corresponding to the output TPSAD of the sensor 52, the calculated accelerator opening APS, the actual throttle opening TPS, and the like are connected so that communication is possible.

  The MPU 66a receives the output of the rotor position sensor 50 (specifically, U, V, W phase Hall sensor output) via the rotor position sensor output detection circuit 66b. The MPU 66a is a signal for controlling the operation of the electric motor 44 based on the output of the rotor position sensor output detection circuit 66b and the accelerator opening APS transmitted from the MPU 64a (specifically, U, V, W phase outputs). Is output to the motor drive circuit 66c. More specifically, the MPU 66a determines (calculates) the target throttle opening (target value) of the throttle valve 24 based on the operating state such as the accelerator opening APS so that the actual throttle opening TPS becomes the target throttle opening. In addition, a signal for controlling the operation of the electric motor 44 is output.

  When the ignition switch 70 is turned on, the throttle valve controller 66 supplies a power circuit 66d that supplies operating power from the battery 72 to the MPU 66a and the electric motor 44, and a battery that is connected to the power circuit 66d and detects the voltage of the battery 72. A voltage detection circuit 66e is provided. The output of the battery voltage detection circuit 66e is input to the MPU 66a, and the MPU 66a determines whether or not the battery 72 can drive the electric motor 44 based on the output or the like (for example, whether the voltage of the battery 72 is equal to or higher than a predetermined voltage). If it is determined that the electric motor 44 can be driven, a permission signal is output.

  Both the permission signal output from the MPU 66a and the permission signal output from the MPU 64a are sent to the AND circuit 66f. The AND circuit 66f outputs a Hi level signal when two permission signals are input, in other words, when it is determined that the battery 72 can drive the electric motor 44 in each of the MPUs 64a and 66a. The relay 66g is closed, and the motor drive voltage from the power supply circuit 66d is supplied to the motor drive circuit 66c.

  When the motor drive voltage from the power supply circuit 66d is supplied (when the permission relay 66g is closed), the motor drive circuit 66c is based on the output from the MPU 66a (coil (U, V, W phase) of the electric motor 44). Output to.

  FIG. 2 is a first half of a flow chart showing the operation of the engine control apparatus according to this embodiment, and FIG. 3 is a second half thereof. The illustrated program is executed only once by the throttle valve controller 66 or the like when the engine 12 is started (specifically, when the ignition switch 70 is turned on by the driver).

  In the following, first, in S10, it is determined whether or not the throttle opening sensor 52 is out of order. In S10, the determination is made based on the output of the throttle opening sensor output detection circuit 64c and the like. When the result in S10 is affirmative, the subsequent processing is skipped. When the result is negative, the process proceeds to S12, and it is determined whether or not the accelerator opening sensor 54 is in failure. The determination in S12 is made based on the output of the accelerator opening sensor output detection circuit 64b and the like. When the determination is affirmative, the subsequent processing is skipped, and when the determination is negative, the processing proceeds to S14.

  In S14, the output APSAD of the accelerator opening sensor 54 is acquired (detected), and the process proceeds to S16 to determine whether or not the acquired output APSAD is a predetermined amount. Since the predetermined amount is a voltage that is output when the accelerator 16 is not operated by the driver and is in the initial position as described above, the processing of S16 is performed when the accelerator 16 is in the accelerator fully closed position (initial position). This corresponds to the determination of whether or not there is.

  When the result in S16 is affirmative, the program proceeds to S18, and the output TPSAD of the throttle opening sensor 52 is acquired (detected). More precisely, the throttle opening corresponding to the position of the throttle valve 24 when the accelerator 16 is in the accelerator fully closed position when it is not driven by the electric motor 44 in S18 (when the electric motor 44 is in a non-energized state). The output of the sensor 52, in other words, the output TPSAD of the throttle opening sensor 52 when the throttle valve 24 is at the initial opening (default opening) is acquired.

  Next, in S20, the output TPSAD acquired in S18 is determined as an initial reference value (TPS default value) TPS_default. Therefore, the “initial reference value” means a reference value corresponding to the initial opening (initial position) of the throttle valve 24 in the output of the throttle opening sensor 52. Thus, the output TPSAD of the throttle opening sensor 52 corresponding to the position of the throttle valve 24 when not driven by the electric motor 44 is determined as the initial reference value TPS_default.

  On the other hand, when the result in S16 is negative, that is, when the output APSAD is larger than the predetermined amount and it is determined that the accelerator 16 is not in the accelerator fully closed position, the process proceeds to S22, and a predetermined initial reference value (specifically, stored in advance in the MPU 66a) The initial reference value or default (initial value) determined in the previous program loop is determined as the initial reference value TPS_default.

  Next, in S24, the voltage difference between the initial reference value TPS_default and the fully closed reference value (described later) stored in the MPU 66a is set as a first predetermined value (TPS offset value) TPS_offset_REF. The first predetermined value TPS_offset_REF is stored in advance in the MPU 66a, and a unique value (voltage value) of the throttle body including the throttle valve 24 is set as an initial value. Thereafter, as will be described later, A voltage value that is updated every time the closing reference value is newly determined, that is, an updatable learning value is set.

Next, in S26, a fully closed reference value estimated from the initial reference value TPS_default (hereinafter referred to as “fully closed reference estimated value”) is obtained. Specifically, a value obtained by subtracting the first predetermined value TPS_offset_REF from the initial reference value TPS_default is determined as a fully closed reference estimated value (TPS lower limit estimated value) TPS_hat_fully_close.

  Proceeding to S28, a fully closed reference candidate value (TPS lower limit learned value) TPS_fully_close_REF, which is a candidate for a fully closed reference value, is set. More specifically, the output of the throttle opening sensor 52 corresponding to the fully closed position of the throttle valve 24 when the engine 12 is started is stored in the MPU 66a. The output is read and the fully closed reference candidate value TPS_fully_close_REF Set as.

What is characteristic here is that the sensor output when the engine 12 is started is set to the fully closed reference candidate value TPS_fully_close_REF. That is, since this program is to be executed when the engine 12 is started, the above-mentioned initial reference value TPS_default or fully closed reference estimate TPS_hat_fully_close the throttle opening sensor 5 second output under the temperature environment at the time of starting the engine Based on. Therefore, by setting the fully closed reference candidate value TPS_fully_close_REF as described above, the fully closed reference candidate value TPS_fully_close_REF and the fully closed reference estimated value TPS_hat_fully_close become values obtained from sensor outputs under substantially the same temperature environment. did.

  Note that the fully closed reference candidate value TPS_fully_close_REF is also stored in advance in the MPU 66a and the unique value (voltage value) of the throttle body is set as an initial value, as with the first predetermined value TPS_offset_REF. As described above, a voltage value that is updated every time the fully closed reference value is newly determined, that is, an updateable learning value is set.

  Next, in S30, the determined full-closed reference estimated value TPS_hat_fully_close is compared with the full-closed reference candidate value TPS_fully_close_REF. Specifically, as shown in the figure, whether or not the absolute value of the difference between the fully closed reference candidate value TPS_fully_close_REF and the fully closed reference estimated value TPS_hat_fully_close is equal to or smaller than a second predetermined value (for example, 0.2 [V]) In other words, it is determined whether or not the fully closed reference candidate value TPS_fully_close_REF and the fully closed reference estimated value TPS_hat_fully_close are relatively close values.

  If the determination in S30 is affirmative, it can be determined that the reliability of the fully closed reference candidate value TPS_fully_close_REF is relatively high, and the process proceeds to S32, where the fully closed reference candidate value TPS_fully_close_REF A reference value corresponding to the fully closed position of the throttle valve 24. TPS lower limit value) TPS_fully_close is determined.

On the other hand, if the absolute value of the difference between the fully closed reference candidate value TPS_fully_close_REF and the fully closed reference estimated value TPS_hat_fully_close is larger than the second predetermined value, the reliability of the fully closed reference candidate value TPS_fully_close_REF is relatively low. it can be determined that, the process proceeds to S34 subsequent processing (forced) actually throttle valve 24 is driven to the closed position determines the output of the throttle opening sensor 5 2 at that time fully closed reference value TPS_fully_close .

  Specifically, in S34, it is determined whether or not the voltage of the battery 72 is equal to or higher than a predetermined voltage. The determination in S34 is made based on the presence / absence of a permission signal output from the MPU 64a or MPU 66a. If the determination is affirmative, the process proceeds to S36.

  In S36, the motor drive voltage of the battery 72 is supplied to the electric motor 44, that is, the electric motor 44 is energized, and the process proceeds to S38 to forcibly drive the throttle valve 24 in the closing direction. The operation of the electric motor 44 is controlled so as to drive the motor. Next, in S40, the output TPSAD generated from the throttle opening sensor 52 is acquired.

  In S42, it is determined whether or not the throttle valve 24 has reached the fully closed position. In other words, it is determined whether or not the throttle valve 24 has been driven to the fully closed position by the electric motor 44. This determination is made based on whether or not the minimum output value TPSADmin of the throttle opening sensor 52 has been updated. Specifically, in a program (not shown), the last obtained (latest) output TPSAD of the throttle opening sensor 52 is compared with the minimum output TPSADmin of the throttle opening sensor 52 obtained so far. When the output TPSAD is less than the minimum value TPSADmin, the latest output TPSAD is updated as a new minimum value TPSADmin. The initial value of the minimum value TPSADmin is an appropriate value that is obtained in advance through experiments.

  Thus, when the minimum value TPSADmin is updated, it can be determined that the throttle valve 24 is driven in the closing direction and has not reached the fully closed position. On the other hand, when the minimum value TPSADmin is not updated, the throttle valve 24 is closed. Therefore, it can be determined that the throttle valve 24 has reached the fully closed position and has come into contact with the fully closed end. In this manner, whether the throttle valve 24 has been driven to the fully closed position is determined based on the output TPSAD of the throttle opening sensor 52 without using a current sensor that detects the current of the electric motor 44. To do.

  If NO in S42, that is, if the throttle valve 24 has not yet been driven to the fully closed position, the process returns to S38, S40 to further drive the throttle valve 24 in the closing direction, and the output TPSAD of the throttle opening sensor 52 is set. Get it again. On the other hand, when the result in S42 is affirmative, the process proceeds to S44, and the last obtained (latest) output TPSAD of the throttle opening sensor 52 is set to the fully closed reference value TPS_fully_close. Thus, when the absolute value of the difference between the fully closed reference candidate value TPS_fully_close_REF and the fully closed reference estimated value TPS_hat_fully_close is larger than the second predetermined value, the throttle valve 24 is driven to the fully closed position by the electric motor 44. The output TPSAD of the throttle opening sensor 52 is determined as the fully closed reference value TPS_fully_close.

  When the fully closed reference value TPS_fully_close is newly determined in S44, the fully closed reference candidate value TPS_fully_close_REF and the first predetermined value TPS_offset_REF are updated as described above. Specifically, in S46, the fully closed reference candidate value TPS_fully_close_REF is updated to the newly determined fully closed reference value TPS_fully_close, and then, in S48, the first predetermined value TPS_offset_REF is newly determined from the initial reference value TPS_default. The fully closed reference value TPS_fully_close is updated to a value obtained by subtraction to prepare for the next program execution. Thus, when the absolute value of the difference between the fully closed reference estimated value TPS_hat_fully_close and the fully closed reference candidate value TPS_fully_close_REF is larger than the second predetermined value, the first predetermined value TPS_offset_REF is updated.

  When the result in S34 is negative, since the voltage of the battery 72 is less than the predetermined voltage and the throttle valve 24 cannot be driven in the closing direction, the process proceeds to S32 and the fully closed reference candidate stored in the MPU 66a. The value TPS_fully_close_REF is determined as the fully closed reference value TPS_fully_close.

  Next, the process proceeds to S50, where the initial opening (specifically, 3 degrees) of the throttle valve 24 is set (determined) as the throttle initial opening TH_default, and the process proceeds to S52, where the throttle valve 24 is fully opened (specifically, substantially omitted). 90 degrees) is set as the throttle fully open position TH_wot. The initial opening and the full opening of the throttle valve 24 described above are set values (unique values) unique to the throttle body and are stored in the MPU 66a.

  Next, the process proceeds to S54, and a fully open reference value corresponding to the fully open position (TH_wot) of the throttle valve 24 (corresponding to the fully open position of the throttle valve 24 at the output of the throttle opening sensor 52) based on at least the determined fully closed reference value TPS_fully_close. The TPS upper limit value) TPS_wot is determined, more precisely, based on the characteristics of the throttle opening sensor 52 obtained from the initial reference value TPS_default and the fully closed reference value TPS_fully_close. The corresponding fully open reference value TPS_wot is determined.

  Hereinafter, determination of the fully open reference value TPS_wot will be specifically described. Since the output of the throttle opening sensor 52 is directly proportional to the position of the throttle valve 24, that is, the throttle opening, as shown in FIG. 4, the initial reference value TPS_default which is the sensor output when the throttle valve 24 is at the throttle initial opening TH_default. If the fully closed reference value TPS_fully_close which is the sensor output when the throttle valve 24 is in the fully closed position (when the throttle opening is 0 degree in FIG. 4) is determined, the throttle opening as shown by the one-dot chain line in FIG. The output characteristic (sensor model) of the degree sensor 52 can be obtained.

Therefore, if the throttle fully open opening TH_wot set in S52 is applied to the output characteristics of the throttle opening sensor 52, a fully open reference value TPS_wot corresponding to the fully open position of the throttle valve 24 (throttle fully open opening TH_wot) is determined ( Estimation). More specifically, the fully open reference value TPS_wot is obtained by the following formula 1.
TPS_wot [V] = ((TPS_default−TPS_fully_close) / TH_default) × TH_wot + TPS_fully_close
... Formula 1

  That is, the difference obtained by subtracting the fully closed reference value TPS_fully_close from the initial reference value TPS_default is divided by the throttle initial opening TH_default (that is, the change in the sensor output is divided by the change in the throttle opening), and the throttle The fully open reference value TPS_wot is obtained by adding the fully closed reference value TPS_fully_close to the value obtained by multiplying the fully opened opening TH_wot. In Equation 1, “throttle initial opening TH_default” is used as the amount of change in the throttle opening because the fully closed opening of the throttle valve 24 is 0 degrees, otherwise Needless to say, the amount of change in the throttle opening is the difference obtained by subtracting the fully closed opening of the throttle valve 24 from the initial throttle opening TH_default.

  When the fully closed reference value and the fully opened reference value in the throttle opening sensor 52 are determined as described above, the target throttle opening of the throttle valve 24 is then determined based on the operating state such as the accelerator opening APS in a program (not shown). (Target value) is determined within a range defined by the fully closed reference value and the fully open reference value. Then, the operation of the electric motor 44 is controlled so that the opening degree of the throttle valve 24 becomes the target throttle opening degree. In this way, the operation of the electric motor 44 is controlled so that the target throttle opening is determined within the range defined by the fully closed reference value TPS_fully_close and the fully opened reference value TPS_wot where the opening of the throttle valve 24 is determined. Is done.

As described above, in the embodiment of the present invention, the control device for the internal combustion engine that controls the operation of the actuator (electric motor) 44 that drives the throttle valve 24 disposed in the intake pipe 22 of the internal combustion engine (engine) 12. , The throttle opening sensor 52 for generating an output indicating the throttle valve opening, and the initial output of the throttle opening sensor corresponding to the throttle valve position (throttle initial opening TH_default) when not driven by the actuator. A reference value TPS_default is determined (S20), and a value obtained by subtracting the first predetermined value TPS_offset_REF from the determined initial reference value is determined as a fully closed reference estimated value TPS_hat_fully_close. Throttle valve controller 66. S26), the internal combustion engine starts the determined full-closed reference estimated value Comparison means (throttle valve controller 66, S30) for comparing with the fully closed reference candidate value TPS_fully_close_REF corresponding to the fully closed position of the throttle valve at the time, the difference between the fully closed reference estimated value and the fully closed reference candidate value is If the difference is less than a predetermined value of 2, the fully closed reference candidate value is determined as a fully closed reference value TPS_fully_close (S32). If the difference is greater than a second predetermined value, the throttle valve is moved to the fully closed position by the actuator. A full-closed reference value determining means (throttle valve controller 66, S44) for determining the output of the throttle opening sensor as a fully-closed reference value when driven to a minimum, based on at least the determined full-closed reference value. Fully open reference value determining means (slot) for determining a fully open reference value TPS_wot corresponding to the fully open position of the throttle valve (throttle fully open opening TH_wot) Rubarubu controller 66.S54) before SL so that the target value determined within the range where the opening degree of the throttle valve is defined by the full-open reference value is fully closed reference value which is the determination (target throttle opening), Actuator control means (throttle valve controller 66) for controlling the operation of the actuator, if the difference between the fully closed reference estimated value TPS_hat_fully_close and the fully closed reference candidate value TPS_fully_close_REF is greater than the second predetermined value, the first predetermined value First predetermined value updating means (throttle valve controller 66) for updating TPS_offset_REF to a value obtained by subtracting the fully closed reference value TPS_fully_close from the initial reference value TPS_default. S48) .

  In this way, the fully closed reference estimated value TPS_hat_fully_close is set to a fully closed reference candidate value (in other words, a temperature environment (operating state) in which the fully closed reference estimated value is determined) when the engine 12 is started. Therefore, it is possible to make the output of the throttle opening sensor 52 less susceptible to the influence of the difference in the temperature environment, because it is compared with the fully closed reference candidate value TPS_fully_close_REF stored in advance. When the difference between the fully closed reference estimated value and the fully closed reference candidate value is less than or equal to the second predetermined value, the fully closed reference candidate value is determined as the fully closed reference value TPS_fully_close, ie, the difference is the second If it is less than the predetermined value, it is determined that the reliability of the fully closed reference candidate value is relatively high, and the fully closed reference candidate value is determined as the fully closed reference value without driving the throttle valve 24 to the fully closed position. Therefore, the fully closed reference value can be determined accurately and quickly, and the power consumption is reduced as compared with the technique described in Patent Document 2 in which the throttle valve is driven to the fully closed position each time the ignition is turned off. be able to.

  Further, when the difference is larger than the second predetermined value, it is determined that the reliability of the fully closed reference candidate value is relatively low, and only when that is the case, the throttle valve 24 is driven to the fully closed position to determine the fully closed reference value. Since the configuration is such that the fully closed reference value can be determined more accurately.

  Further, a fully open reference value TPS_wot corresponding to the fully opened position of the throttle valve 24 is determined based on at least the determined fully closed reference value, and the opening degree of the throttle valve 24 is determined by the fully closed reference value and the fully opened reference value. Since the operation of the electric motor 44 is controlled so as to reach the target throttle opening determined within the specified range, for example, the actual throttle valve 24 reaches the fully closed position and hits the fully closed end. When in the contact state, the electric motor 44 does not further drive the throttle valve 24 in the closing direction, so that the load current of the electric motor 44 increases and the battery 72 consumes unnecessary power. Nor.

  Further, when the difference between the fully closed reference estimated value TPS_hat_fully_close and the fully closed reference candidate value TPS_fully_close_REF is larger than the second predetermined value, the first predetermined value TPS_offset_REF is changed from the initial reference value TPS_default to the fully closed reference value TPS_fully_close. A first predetermined value updating means (throttle valve controller 66, S48) for updating to a value obtained by subtraction is provided. As a result, the first predetermined value can be set to a value corresponding to the newly determined full-closed reference value, and therefore the full-closed reference estimated value obtained using the first predetermined value is accurately determined. Can do.

  The fully open reference value determining means sets the throttle valve 24 to a fully open position (throttle fully open opening TH_wot) based on the characteristics of the throttle opening sensor 52 obtained by the initial reference value TPS_default and the fully closed reference value TPS_fully_close. The corresponding fully open reference value TPS_wot is determined. As described above, since the throttle valve is configured to determine the fully open reference value without being driven to the fully open position as in the technique described in Patent Document 1, the time required for driving the throttle valve 24 to the fully open position is as follows. The fully open reference value can be determined quickly.

  In the above description, the motorcycle 10 is described as an example of the saddle-ride type vehicle on which the engine 12 is mounted. However, the present invention is not limited to this, and a driver such as a scooter or an ATV (All Terrain Vehicle) It may be a saddle-ride type vehicle that rides over a saddle), and may be another vehicle.

  Further, the engine 12 is configured to be a single cylinder engine, but is not limited thereto, and may be a multi-cylinder engine such as a two-cylinder engine.

  Further, the engine 12 exhaust amount, the throttle initial opening TH_default, the second predetermined value, and the like are specifically shown, but these numerical values are illustrative and not limited.

  In addition, the fully open reference value TPS_wot is determined based on the characteristics of the throttle opening sensor 52 obtained from the initial reference value TPS_default and the fully closed reference value TPS_fully_close, but is not limited thereto. A value obtained by adding the predetermined values may be determined as the fully open reference value TPS_wot.

1 is a schematic diagram showing an overall control apparatus for an internal combustion engine according to an embodiment of the present invention. FIG. 3 is a first half portion of a flow chart showing the operation of the control device for the internal combustion engine shown in FIG. 1. FIG. It is the latter half part of the flow chart shown in FIG. 2 is a graph showing a characteristic of an output of a throttle opening sensor with respect to a throttle opening of the internal combustion engine shown in FIG.

Explanation of symbols

  12 engine (internal combustion engine), 22 intake pipe, 24 throttle valve, 44 electric motor (actuator), 52 throttle opening sensor, 66 throttle valve controller

Claims (2)

In a control device for an internal combustion engine that controls the operation of an actuator that drives a throttle valve disposed in an intake pipe of the internal combustion engine,
a. A throttle opening sensor for generating an output indicating the opening of the throttle valve;
b. Obtained by determining the output of the throttle opening sensor corresponding to the position of the throttle valve when not driven by the actuator as an initial reference value and subtracting a first predetermined value from the determined initial reference value A closed reference estimation value determining means for determining a value as a closed reference estimation value;
c. Comparing means for comparing the determined full-closed reference estimated value with a full-closed reference candidate value corresponding to a full-closed position of the throttle valve when the internal combustion engine is started;
d. When the difference between the fully closed reference estimated value and the fully closed reference candidate value is less than or equal to a second predetermined value, the fully closed reference candidate value is determined as a fully closed reference value, while the difference is greater than a second predetermined value. A fully closed reference value determining means for determining the output of the throttle opening sensor when the throttle valve is driven to the fully closed position by the actuator as a fully closed reference value;
e. A fully open reference value determining means for determining a fully open reference value corresponding to a fully open position of the throttle valve based on at least the determined fully closed reference value ;
f. Actuator control means for controlling the operation of the actuator so that the opening of the throttle valve becomes a target value determined within a range defined by the determined fully closed reference value and fully opened reference value;
and
g. If the difference between the full-closed reference estimated value and the full-closed reference candidate value is larger than the second predetermined value, the first predetermined value is obtained by subtracting the full-closed reference value from the initial reference value. First predetermined value updating means for updating;
A control device for an internal combustion engine, comprising: The fully open reference value determining means determines a fully open reference value corresponding to the fully open position of the throttle valve based on the characteristics of the throttle opening sensor obtained from the initial reference value and the fully closed reference value. the control system of claim 1 Symbol placement of an internal combustion engine.

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