JP2005171915A - Electronic throttle control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic throttle control device restraining erroneous learning caused by temperature characteristics and learning a full close position at a time of learning full close position of a throttle valve directly opened and closed by a motor. <P>SOLUTION: Full close position learning is performed under a condition where a throttle valve surely abuts on the full close position by hitting control of the throttle valve (step 203, 204). The full close position detected by the throttle sensor is reflected to a learning value stored in back up memory with a predetermined normalizing rate at a time of learning (step 206). Consequently, erroneous learning of the full close position can be restrained even if deformation quantity at a time of throttle valve hitting greatly changes due to temperature characteristics of a throttle system composed of resin or the like. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an electronic throttle control device that is provided in an intake passage and adjusts the amount of air supplied to a cylinder of an internal combustion engine by adjusting the opening thereof, and particularly relates to a device that learns the fully closed position of a throttle valve. It is.

  2. Description of the Related Art Conventionally, there has been known one that learns the throttle valve fully closed position as a reference position and controls the throttle valve opening based on the learned fully closed position. In such a throttle control device, since the reference position learned as the fully closed position is used, if the wrong learning is performed, the air amount required by the engine is insufficient, or conversely, the driver feels uncomfortable. There is a risk of giving.

Therefore, as a technique for accurately learning the reference position, a technique for learning the fully closed position by setting the target opening of the throttle valve at a position sufficiently beyond the fully closed position of the throttle valve is known (patent) Reference 1). In this case, the throttle valve driven by feedback control of the motor with respect to the target opening sufficiently exceeding the fully closed position is reliably moved to the fully closed position before the target position. Then, the signal detected by the throttle sensor in the state of being reliably moved to the fully closed position is learned as the fully closed position.
JP 2000-110634 A

  As described above, when the throttle valve is brought into contact with the fully closed position and the fully closed position at that time is learned, the ambient temperature is not always constant for each learning. If the ambient temperature changes for each learning, the dimensions and the amount of distortion at the time of abutment to the fully closed position change depending on the temperature characteristics of the parts constituting the throttle system. In this situation, when the fully closed position of the throttle valve is learned, although the actual fully closed position does not change, the size and amount of distortion change due to changes in temperature characteristics. There is a possibility of mislearning.

  In particular, when the material such as a gear unit that constitutes the slot system is made of resin or the like, the amount of distortion at the time of abutment and the dimensions thereof will change greatly. Even if the throttle valve is controlled on the basis of the closed position, there is a problem that the control of the internal combustion engine cannot be executed with high accuracy.

  Accordingly, an object of the present invention is to learn the fully closed position of the throttle valve while suppressing the influence even if the size or the amount of distortion at the time of abutment changes due to the temperature characteristics of the slot system parts. An object of the present invention is to provide a control device for an electronic throttle.

  Therefore, according to the first aspect of the present invention, the throttle sensor for detecting the actual opening of the throttle valve is provided, and the actual opening of the throttle valve detected by the throttle sensor is determined by the operation state and the contact position of the throttle valve. In the electronic throttle control device that controls the throttle valve so that the target opening of the throttle valve is set based on the learned value, the storage means for storing the learned contact position in a backup memory, and the throttle valve Learning means for learning the contact position in a state of being in contact with the contact position, and the learning means stores the contact position detected by the throttle sensor in the backup memory by a predetermined smoothing process. The learning value of the contact position is updated by reflecting the learning value.

  This suppresses learning of the contact position detected by the throttle sensor at that time each time learning is updated. Therefore, even though the actual contact position has not changed, even if the amount of distortion at the time of abutment due to temperature characteristics or the dimensions of the components of the throttle system change, the contact position is erroneously learned. Thus, learning of the fully closed position can be executed.

  In the invention according to claim 2, a throttle sensor for detecting the actual opening of the throttle valve is provided, and the actual opening of the throttle valve detected by the throttle sensor is based on the learning value of the operating state and the contact position of the throttle valve. In an electronic throttle control device that controls the throttle valve so that the target opening of the throttle valve is set based on the storage valve, the storage means for storing the learned contact position in a backup memory; Learning means for learning the contact position in a state of striking a position, and the learning means uses a learning value stored in the storage means and a throttle sensor for a learning value stored in the storage means. When a deviation from the detected contact position is reflected, a predetermined guard process is performed on the deviation and learning is updated. Do.

  Thereby, when reflecting the deviation between the learning value of the backup memory and the fully closed position detected by the throttle sensor this time with respect to the learning value of the fully closed position stored in the backup memory, A predetermined guard process is executed.

  Therefore, for example, even when the fully closed position becomes a large erroneous value due to temperature characteristics, erroneous learning is suppressed by the predetermined guard process, and the actual contact position changes as in the invention according to claim 1. Despite this, even if the amount of distortion at the time of abutment due to temperature characteristics and the size of the throttle system parts change, the inconvenience that the contact position is mistakenly learned is suppressed, and the fully closed position is Learning can be performed.

  According to a third aspect of the present invention, a throttle sensor for detecting the actual opening of the throttle valve is provided, and the actual opening of the throttle valve detected by the throttle sensor is determined by the learning value of the operating state and the contact position of the throttle valve. In an electronic throttle control device that controls the throttle valve so that the target opening of the throttle valve is set based on the storage valve, the storage means for storing the learned contact position in a backup memory; Learning means for learning the contact position in a state of striking the position, and when the contact position detected by the throttle sensor is larger than the learning value stored in the storage means, the learning means A learning update is performed by adding the first predetermined value to the learning value stored in the storage means. Subtracting a second predetermined value from the stored learned values to the means for learning updates.

  Thereby, the fully closed position detected by the sensor is learned depending on whether the fully closed position detected by the sensor is larger or smaller than the learned value of the fully closed position stored in the backup memory. The learning value is updated by adding the first predetermined value to the value or subtracting the second predetermined value.

  Therefore, for example, even when the fully closed position becomes a large erroneous value due to temperature characteristics, erroneous learning due to a large change in the learning value is suppressed. Therefore, as in the first and second aspects of the invention, although the actual contact position has not changed, the amount of distortion at the time of abutment due to temperature characteristics and the dimensions of the components of the throttle system change. However, it is possible to execute the learning of the fully closed position while suppressing the inconvenience that the contact position is erroneously learned.

  According to a fourth aspect of the present invention, the electronic throttle control device includes a connecting means for connecting a throttle valve of the electronic throttle control device and a driving means for driving the throttle valve, and the material of the connecting means varies in size or distortion depending on temperature. And good.

  According to the invention which concerns on Claim 5, the said connection means consists of resin materials. In the case of a resin material, the amount of distortion at the time of abutment and the dimensions of the resin material change greatly depending on the temperature characteristics. This can easily lead to erroneous learning, resulting in inconvenience that the throttle control cannot be executed accurately. End up. Therefore, it may be applied to a throttle system made of such a resin material.

(First embodiment)
FIG. 1 shows an overall system to which an electronic throttle control device of the present invention is applied. In the intake passage, a filter 3 for removing foreign matters mixed in the intake air from the upstream side, an air flow meter 4 for detecting the intake air amount supplied to the engine 1 on the downstream side, and the intake air amount A throttle valve 5 is provided for adjusting.

  Further, an intake manifold 6 for supplying intake air to each cylinder 9 of the engine 1 is provided downstream of the intake passage. The intake manifold 6 is provided with an injector 7 for supplying fuel to each cylinder 9. An intake valve 8 that opens and closes at a predetermined timing is provided at the inlet of each cylinder 9 of the engine 1, and an exhaust valve 13 that opens and closes at a predetermined timing is provided at the outlet.

  In the combustion in the engine 1, the air-fuel mixture of the intake air adjusted by the throttle valve 5 and the fuel injected by the injector 7 is confined in the cylinder 9 of the engine 1 when the intake valve 8 is opened and compressed. Near the top dead center, a mixture of fuel and intake air injected by an injector 7 provided in the intake manifold 6 by the spark plug 10 is supplied to the cylinder 9 when the intake valve 8 is opened, and the spark of the spark plug 10 is sparked. It is subjected to combustion by ignition. The combustion gas is discharged to the exhaust manifold 14 when the exhaust valve 13 is opened.

  When the piston 11 is pushed down by such a series of combustion operations, the crankshaft 12 is rotated. This rotational power is the power generated by the engine 1.

  In order to control the combustion of the engine 1 as described above, the ECU 20 precisely controls the combustion operation described above based on various sensor signals. The ECU 20 includes an A / D conversion circuit 27 for A / D converting various sensor signals, a ROM 22 as a read-only memory, and a RAM 23 as a backup memory. The CPU 21 as a central processing unit is based on these information. Thus, a predetermined command is output to the injector drive circuit 24 and the motor drive circuit 25 to control the motor 19 that drives the injector 7 and the throttle valve 5.

  As signals from various sensors, an air flow meter 4 for detecting the intake air amount GN, a crank sensor 15 for detecting the engine rotational speed NE provided on the crankshaft 12, and a throttle provided on the rotary shaft 5a of the throttle valve. A position sensor 16 (main sensor, sub sensor), an accelerator position sensor 18 (main sensor, sub sensor) provided on the accelerator pedal 17 and the like are input.

  Next, the throttle valve control system will be described in detail with reference to FIG. The ECU 20 determines a target throttle opening based on the accelerator position Ap detected by the accelerator position sensor 18. Then, the motor 19 is feedback-controlled based on the detected value (actual throttle opening TH) of the throttle opening sensor 16 so that the actual throttle opening TH becomes the target opening.

  The drive shaft of the motor 19 is connected to the reduction gear unit 30. The rotation of the drive shaft of the motor 19 is transmitted to the throttle valve 5 through the reduction gear unit 30, and the throttle valve 5 is opened and closed.

  A stopper 34 is provided for the final stage gear 30 a of the reduction gear unit 30. When the motor 19 rotates the throttle valve 5 to the closing side, the gear 30a at the final stage comes into contact with the stopper 34 and the rotation of the throttle valve 5 stops.

  In the present embodiment, the position at which the final stage gear 30 a contacts the stopper 34 is the fully closed position of the throttle valve 5.

  In this configuration, the control voltage to the throttle valve 5 is determined in the present embodiment. A control program for setting the control voltage to the throttle valve 5 will be described with reference to FIG. In this program, the final target opening of the throttle valve 5 is calculated based on the ISC required opening and the required opening other than the ISC in the idle operation state. The final target opening is corrected using the learned fully closed reference position.

  First, in step 101, the ISC required opening is calculated. The required opening of the ISC is a solid variation or aging when the target opening of the engine cannot be obtained even if the base opening of the throttle valve 5 required to reach the target engine speed and the base opening are set. It consists of a learning value for correcting the deviation of the intake air amount caused by the change.

  Next, in step 102, various required opening degrees are calculated. Examples of the various required opening degrees include an opening degree for outputting engine torque corresponding to the depression amount of the accelerator pedal 17, and an opening degree necessary for running the vehicle speed at a constant speed. Further, the opening required for increasing the intake air according to the ignition timing delay at the time of early catalyst warm-up, or the opening required according to a load such as an air conditioner or power steering may be used.

  In step 103, a final target opening is calculated based on the ISC required opening and various required opening. The final target opening calculated in this way is converted from the opening of the throttle valve 5 to the final target voltage to the throttle valve 5 using a map in step 104.

  In step 105, the control value of the throttle valve 5 is calculated by adding the learning value of the fully closed position to the final target voltage.

  As described above, the throttle valve 5 is controlled by reflecting the learned value of the fully closed reference position.

  When the fully closed position learned for the control of the throttle valve 5 is used, the learning accuracy of the fully closed position is important. By the way, in recent years, the material of the gear constituting the slot system may be made of resin or the like, and the resin or the like is easily affected by temperature.

  For example, when the temperature changes, the size of the gear unit 30 for controlling the throttle and the distortion amount when the throttle valve 5 is brought into contact with the fully closed position also change greatly. It is easy to invite, and even if such an incorrect learning value is used, there arises a disadvantage that the throttle control cannot be executed accurately.

  Therefore, the present invention learns the reference position of the throttle valve while suppressing the influence even when the size or the amount of distortion at the time of abutment changes due to the temperature characteristics of the slot system parts. This characteristic part of the present invention will be described with reference to the flowchart of FIG.

  In the flowchart of FIG. 4, the throttle valve 5 is brought into the fully closed position, and the output value of the throttle sensor 16 at that time is used for learning update. In this learning update, the current fully closed position is not reflected as a learned value, but the current fully closed position is reflected in the past learned value. In this way, it is possible to suppress erroneous learning using the erroneously closed position as the reference position even if the size and the amount of distortion change depending on the temperature characteristics.

  First, in step 201, it is determined whether the ignition switch IG is turned on. This is the timing at which the ignition switch IG is turned on immediately before starting the engine. Therefore, since the throttle valve 5 can be fully closed at this timing, the learning timing is determined when the ignition switch IG is turned on.

  If the ignition switch IG is not turned on, this routine is terminated as it is. On the other hand, if it is determined in step 201 that the ignition switch IG has been turned ON, the process proceeds to step 202, where it is determined whether the learning end flag is ON. The learning end flag is a flag for determining whether learning update of the fully closed position of the throttle valve 5 has been completed after the ignition switch IG is turned on. If this learning end flag is ON, this routine is ended as it is.

  On the other hand, if the learning end flag is not ON, the routine proceeds to step 203, where the fully closed butting control of the throttle valve 5 is performed. In the fully closed butting control, the throttle valve 5 is surely butted to the fully closed position by setting the target opening of the throttle valve 5 to a position sufficiently smaller than the fully closed position. At this time, the control duty increases in order to compensate for the deviation between the target position and the fully closed position by the feedback control of the throttle valve 5 described above.

  In step 204, in order to detect this state, it is determined whether or not a state in which the control duty is larger than a preset threshold value has passed a predetermined time. If such a state does not reach the predetermined time, this routine is terminated as it is. On the other hand, if the above state continues for a predetermined time, the process proceeds to step 205.

  In step 205, it is determined whether the learning experience flag is ON. The learning experience flag is a flag that is set when learning is executed once, and is a flag that is not cleared once learning is completed until the battery is removed. This flag is used to determine whether learning has been executed even once.

  If the learning experience flag is not ON, it is the first learning, and therefore the process proceeds to step 208, where the output value of the throttle sensor 16 is used as the learning value as the fully closed position learning value. Then, once learning is completed, the process proceeds to step 209, the learning experience flag is turned ON, and further, the learning end flag is turned ON in step 207, and this routine is ended.

  On the other hand, if the learning experience flag is ON and learning has already been performed in the past, the process proceeds to step 206, where the fully closed position learning value is updated. In the update of the fully closed position learning value, 1/4 smoothing is used. That is, the fully closed position detected by the throttle sensor 16 at the current learning timing is reflected on the previous fully closed position learning value stored in the backup memory RAM 23. Then, the process proceeds to step 207, the learning end flag is set to ON, the learning value calculated in the backup memory RAM 24 is stored, and this routine is ended.

  As described above, in the present embodiment, when learning is updated, the output value of the throttle sensor 16 is not set as the learning value, but the current output value of the throttle sensor 16 is set with respect to the previous learning value. It was set as the structure reflected in a predetermined ratio. By updating at a predetermined rate in this way, even if the size or the amount of distortion at the time of abutment changes due to the temperature characteristics of the slot system parts, the influence is suppressed and the throttle valve 5 is fully closed. Can learn.

  In the present embodiment, the learning execution condition is exemplified when the ignition switch is turned on. However, the learning execution condition is not limited to this, and when the ignition switch is turned off, or even during operation, fuel cut, etc. If there is a timing for learning the reference position, such a state may be used as a learning execution condition.

  In learning update, 1/4 smoothing is used, but not limited to this, 1/16 smoothing or 1/32 smoothing may be used, which is determined by the material of parts used in the electronic throttle system. Just do it.

  Further, the throttle valve fully closed position has been described as an example, but the present invention is not limited to this, and may be applied to learning of the fully open position.

  In the present embodiment, the learning means corresponds to the flowchart of FIG. 4, and the storage means corresponds to means for storing the learning value calculated by the learning means in the backup memory 23.

(Second Embodiment)
Next, a second embodiment will be described using the flowchart of FIG. This embodiment is different from the first embodiment in the learning update method. In the first embodiment, the learning update is performed by the annealing process. However, in the present embodiment, the same effect as in the first embodiment is obtained by applying a guard during the learning update.

  In the flowchart of FIG. 5, the same steps as those in the first embodiment are denoted by the same reference numerals as those in FIG. 4 and the description thereof is omitted, and only the portions different from FIG. 4 will be described in detail.

  In the flowchart of FIG. 5, when the learning execution condition is satisfied, the butting control of the throttle valve 5 is executed, and the learning update is performed, the fully closed position learning value is calculated in step S306. The fully closed position learning value is obtained by adding the deviation between the output value of the throttle sensor 16 and the previous fully closed position learned value to the fully closed position learned value stored in the previous backup memory RAM 23. When this deviation is added, an upper and lower limit guard for the deviation is set, and when the deviation occurs, a guard value is added.

  In this way, as in the first embodiment, even if the size or the amount of distortion at the time of abutment changes due to the temperature characteristics of the slot-type parts, the influence is suppressed and the throttle valve 5 is accurately controlled. The fully closed position can be learned.

  In the present application, the upper and lower limit guards have been described as being constant, but this value may be variably set in accordance with the environmental temperature of the throttle system components.

  Further, the throttle valve fully closed position has been described as an example, but the present invention is not limited to this, and may be applied to learning of the fully open position.

  In the present embodiment, the learning means corresponds to the flowchart of FIG.

(Third embodiment)
Next, a third embodiment will be described using the flowchart of FIG. This embodiment is different in learning update method from the first and second embodiments. In the first embodiment, the learning update is performed by the annealing process. However, in this embodiment, it is possible to prevent the learning value from being largely changed by adding or subtracting a predetermined value during the learning update. Since this is possible, the same effect as in the first embodiment is obtained.

  In the flowchart of FIG. 6, the same steps as those in the first embodiment are denoted by the same reference numerals as those in FIG. 4 and the description thereof will be omitted, and only portions different from those in FIG. 4 will be described in detail.

  In the flowchart of FIG. 5, the learning execution condition is satisfied, the butting control of the throttle valve 5 is executed, and learning is updated. First, at step 406, it is determined whether the fully closed position learning value stored in the backup memory RAM 23 and the fully closed position detected by the throttle sensor 16 are the same value. If they are the same, the learned value needs to be updated. In step 207, the learning end flag is turned on and the routine is terminated. On the other hand, if this condition is not satisfied, the routine proceeds to step 407.

  In step 407, it is determined whether the learning value stored in the backup memory RAM 23 is larger than the fully closed position detected by the throttle sensor 16. If larger, in step 408, the predetermined value 1 is added to the learning value stored in the backup memory RAM 23, and the process proceeds to step 207.

  On the other hand, if the learning value stored in the backup memory RAM 23 is smaller than the fully closed position detected by the throttle sensor 16, the predetermined value 2 is calculated from the learning value stored in the backup memory RAM 23 in step 409. Subtract and go to step 207 to end this routine.

  In this way, as in the first and second embodiments, even if the size or the amount of distortion at the time of abutment changes due to the temperature characteristics of the slot system parts, the influence is suppressed and the throttle valve 5 is suppressed. The fully closed position can be learned.

  In the present embodiment, the predetermined value 1 and the predetermined value 2 may be the same value or may be different. In particular, when the learning value of the fully closed position is updated to the side where the throttle valve 5 is opened, the amount of intake air increases, and the torque generated by the engine 1 increases. For this reason, the predetermined value 1 is preferably set smaller than the predetermined value 2.

  Further, the throttle valve fully closed position has been described as an example, but the present invention is not limited to this, and may be applied to learning of the fully open position.

  In this embodiment, the learning means corresponds to the flowchart of FIG.

1 is a schematic diagram of an entire system to which the present invention is applied. It is a figure which shows the electronic throttle system of this invention. It is a flowchart which shows control of the electronic throttle system of this invention. It is a flowchart which shows the fully closed position learning of 1st Embodiment. It is a flowchart which shows the fully closed position learning of 2nd Embodiment. It is a flowchart which shows the fully closed position learning of 3rd Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... Intake passage, 3 ... Filter, 4 ... Air flow meter, 5 ... Throttle valve, 5a ... Rotary shaft of throttle valve, 6 ... Intake manifold, 7 ... injector, 8 ... intake valve, 9 ... combustion chamber, 10 ... spark plug, 11 ... piston, 12 ... crankshaft, 13 ... exhaust valve, 14 ... Exhaust manifold, 15 ... crank sensor, 16 ... throttle sensor, 17 ... accelerator pedal, 18 ... accelerator sensor, 19 ... motor, 20 ... ECU, 21 ... CPU, 22 ... ROM, 23 ... RAM, 24 ... injector drive circuit, 25 ... motor drive circuit, 27 ... A / D conversion circuit, 30 ... gear unit, 30a ... The final stage of the gear, 31 ... throttle lever, 33 ... spring, 34 ... stopper.

Claims (5)

A throttle sensor for detecting an actual opening of the throttle valve, wherein the actual opening of the throttle valve detected by the throttle sensor is set based on an operating state and a learning value of a contact position of the throttle valve; In an electronic throttle control device that controls the throttle valve so as to achieve a target opening of
Storage means for storing the learned contact position in a backup memory;
Learning means for learning the contact position in a state in which the throttle valve is in contact with the contact position;
The learning means updates the learning value of the contact position by reflecting the contact position detected by the throttle sensor in a learning value stored in the backup memory by a predetermined smoothing process. Electronic throttle control device. A throttle sensor for detecting an actual opening of the throttle valve, wherein the actual opening of the throttle valve detected by the throttle sensor is set based on an operating state and a learning value of a contact position of the throttle valve; In an electronic throttle control device that controls the throttle valve so as to achieve a target opening of
Storage means for storing the learned contact position in a backup memory;
Learning means for learning the contact position in a state in which the throttle valve is in contact with the contact position;
The learning means reflects the deviation between the learning value stored in the storage means and the contact position detected by the throttle sensor with respect to the learning value stored in the storage means. An electronic throttle control device, wherein a predetermined guard process is performed and learning is updated. A throttle valve having a throttle sensor for detecting an actual opening of the throttle valve, wherein the actual opening of the throttle valve detected by the throttle sensor is set based on an operating state and a learning value of a contact position of the throttle valve In an electronic throttle control device that controls the throttle valve so as to achieve a target opening of
Storage means for storing the learned contact position in a backup memory;
Learning means for learning the contact position in a state in which the throttle valve hits the contact position;
The learning means adds a first predetermined value to the learning value stored in the storage means when the contact position detected by the throttle sensor is larger than the learning value stored in the storage means. An electronic throttle control device that performs learning update and, if smaller, performs learning update by subtracting a second predetermined value from a learning value stored in the storage means. A connecting means for connecting a throttle valve of the electronic throttle control device and a driving means for driving the throttle valve;
The electronic throttle control device according to any one of claims 1 to 3, wherein a material of the connecting means varies in size or distortion depending on temperature. 5. The electronic throttle control device according to claim 4, wherein the connecting means is made of a resin material.

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