JP2011099357A - Control device for spark ignition internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To overcome the following problems: a restart process is easily prolonged in a control device for a spark ignition internal combustion engine 10, having a function of performing an automatic stop process and the restart process for the spark ignition internal combustion engine 10 employing a 4-stroke cycle. <P>SOLUTION: Even during the automatic stop process for the internal combustion engine 10, a crank counter as phase information with a 4-stroke as one cycle is updated based on the output of a crank angle sensor 36 as an MRE sensor. When a restart condition is satisfied, fuel injection control is immediately allowed; meanwhile, ignition control is prohibited until the crank counter is evaluated to be highly reliable by comparison with output of cam angle sensors 42a, 42b. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a control device for a spark ignition internal combustion engine having a function of performing automatic stop processing and restart processing of a spark ignition internal combustion engine employing a four-stroke cycle.

  An internal combustion engine employing a four-stroke cycle performs four strokes (strokes) of intake, compression, combustion, and exhaust during a period in which the crankshaft of the internal combustion engine rotates twice. For this reason, in performing fuel injection control and ignition control, phase information with two cycles (four strokes) of the crankshaft as one cycle is required. Therefore, when starting the internal combustion engine, phase information is specified by using the output of the cam angle sensor that detects the rotation angle of the camshaft in addition to the output of the crank angle sensor that detects the rotation angle of the crankshaft. In general, a so-called cylinder discrimination process is performed.

  On the other hand, in the case of performing so-called idle stop control that is an automatic stop process of an on-vehicle internal combustion engine when waiting for a signal at an intersection or the like, a cylinder discrimination process may be required even during the restart process of the internal combustion engine. This is partly because the electromagnetic pickup type sensor that is widely used as a crank angle sensor cannot detect the rotation angle in the low rotation speed region.

  Incidentally, among the crank angle sensors, there is also a sensor using a ferromagnetic magnetoresistive element (MRE) (hereinafter referred to as an MRE sensor). The MRE sensor has an advantage that the rotation angle can be detected even when the rotation speed is zero. Therefore, in the case of performing the idle stop control, the rotation angle of the internal combustion engine can be monitored even after the automatic stop process by using the MRE sensor. For this reason, it is considered that the phase information can be used without performing the cylinder discrimination process during the restart process.

  As conventional techniques for calculating the rotation angle of the crankshaft of an internal combustion engine, for example, there are Patent Documents 1 and 2 below.

JP-A-60-025410 Japanese Patent No. 3870401

  However, even if the rotation angle of the crankshaft can be detected during the automatic stop process as described above, there is a case where noise is superimposed on the output of the crank angle sensor when the internal combustion engine is stopped. May cause the phase information recognized by the control device to deviate from the correct information. Under such circumstances, when the internal combustion engine is restarted, fuel injection control and ignition control cannot be performed at an appropriate timing. On the other hand, when the ignition control or the like is executed after the cylinder discrimination process is completed during the restart process, the time required for the restart process may be prolonged, leading to a decrease in drivability.

  The present invention has been made to solve the above-described problems, and has an object of having a function of performing automatic stop processing and restart processing of a spark ignition type internal combustion engine employing a four-stroke cycle. Another object of the present invention is to provide a spark ignition type internal combustion engine control device capable of performing restart processing as quickly as possible.

  Hereinafter, means for solving the above-described problems and the operation and effects thereof will be described.

  According to a first aspect of the present invention, there is provided a control device for a spark ignition type internal combustion engine having a function of performing an automatic stop process and a restart process of a spark ignition type internal combustion engine employing a four-stroke cycle. Using the detection result of the detected crank angle detection means as input, phase data, which is data that is referred to in both fuel injection control and ignition control, with four strokes of the internal combustion engine as one cycle, is converted into the internal combustion engine by the automatic stop processing. Based on a comparison between the calculation means for continuously calculating including the period during which the combustion control of the engine is stopped, the detection result of the cam angle detecting means for detecting the rotation angle of the cam shaft of the internal combustion engine, and the phase data , An evaluation means for evaluating the reliability of the phase data, and the first fuel for the restart process regardless of the output of the evaluation means And injection control means for executing morphism, said by the evaluating means if the reliability of the phase data is determined to be low, characterized in that it comprises a prohibiting means for prohibiting the ignition control of the internal combustion engine.

  In the above invention, when it is determined that the reliability of the phase data is low, by prohibiting the ignition control, it is possible to suitably avoid a situation in which the internal combustion engine is burdened by ignition in an inappropriate phase. it can. Moreover, the first fuel injection for the restart process is performed regardless of whether or not the reliability of the phase data is lowered, so even when the reliability is recovered immediately before the ignition control, A situation where fuel injection is not in time can be avoided. For this reason, the restart process can be performed as quickly as possible.

  According to a second aspect of the present invention, in the first aspect of the invention, when the evaluation unit determines that the reliability of the phase data is low, a limiting unit that limits the number of fuel injections for the restart process is provided. It is further provided with the feature.

  In the above-described invention, it is possible to avoid the fuel injection being performed many times in a situation where the ignition control is prohibited.

  According to a third aspect of the present invention, in the first or second aspect of the invention, when the evaluation means determines that the reliability of the phase data is low, the phase data is calculated based on a detection result of the cam angle detection means. The correction means further includes a correction means, and the evaluation means changes the evaluation of the reliability of the phase data to an evaluation that the reliability of the phase data is high by correcting the phase data by the correction means. It is characterized by doing.

  The invention according to claim 4 is the invention according to claim 3, wherein the cam angle detecting means is capable of detecting the rotation angle of the cam shaft at an interval shorter than one rotation of the crank angle, The correcting means corrects the phase data based on phase information included in an output signal of the cam angle detecting means.

  In the above invention, even if the crank angle detection means can detect the reference position, in general, the phase data can be corrected earlier than when the detection of the reference position is used.

  The invention according to claim 5 is the invention according to claim 3, wherein the crank angle detection means has a function of detecting a reference crank angle, and the crank angle detection means detects the reference crank angle. And cylinder discrimination means for performing cylinder discrimination based on the detection result of the cam angle detection means, and the correction means corrects the phase data based on cylinder discrimination by the cylinder discrimination means. .

  The invention according to claim 6 is the invention according to any one of claims 1 to 5, characterized in that the crank angle detecting means includes an MRE sensor.

  The inventors found that the MRE sensor may output a signal when the detection target is rotating, even if the detection target is stopped, depending on the arrangement of the detection target. Yes. For this reason, the present invention provided with the MRE sensor has a particularly great utility value of the evaluation means and the like.

  According to a seventh aspect of the invention, in the sixth aspect of the invention, the cam angle detecting means includes an MRE sensor, and an edge of the detection target is provided at a central portion of the MRE sensor provided in the crank angle detecting means. In the case of being positioned, the detection target edge is set so as not to be positioned at the center of the MRE sensor provided in the cam angle detecting means.

  In the above invention, when both the detection target of the MRE sensor provided in the crank angle detection means and the detection target of the detection target MRE sensor provided in the cam angle detection means are both stationary, both of the MRE sensors are detected. It is possible to preferably avoid erroneous detection of rotation.

1 is a system configuration diagram according to a first embodiment. FIG. The flowchart which shows the procedure of the count-up process of the crank counter concerning the embodiment. The flowchart which shows the procedure of the restart process concerning the embodiment. The time chart for demonstrating the problem of a MRE sensor. The flowchart which shows the procedure of the restriction | limiting process of ignition control at the time of the restart process concerning the said embodiment. The flowchart which shows the procedure of the calculation process of the crank angle collation data concerning the embodiment. The flowchart which shows the process sequence of the reliability evaluation of the crank counter concerning the embodiment. The flowchart which shows the procedure of the cylinder discrimination | determination process concerning the embodiment. The time chart which shows the correction | amendment aspect of the crank counter concerning the embodiment. The flowchart which shows the process sequence of the reliability evaluation of the crank counter concerning 2nd Embodiment. The flowchart which shows the procedure of the correction process of the crank counter concerning the embodiment. The time chart which shows the correction | amendment aspect of the crank counter concerning the embodiment.

(First embodiment)
Hereinafter, a first embodiment of a control device for a spark ignition internal combustion engine according to the present invention will be described with reference to the drawings.

  FIG. 1 shows a system configuration according to the present embodiment.

  The illustrated internal combustion engine 10 is a spark ignition internal combustion engine, and is assumed to be an intake port injection type in particular. The internal combustion engine 10 is a so-called four-stroke cycle engine in which four strokes (strokes) of intake, compression, combustion, and exhaust are defined as one cycle, and one cycle corresponds to two rotations.

  A fuel injection valve 14 is provided in the intake passage 12 of the internal combustion engine 10. The fuel is mixed with the air sucked from the upstream of the intake passage 12 by the fuel injection from the fuel injection valve 14. Qi is generated. The intake passage 12 communicates with the combustion chamber 16 by opening the intake valve 18. A spark plug 20 protrudes from the combustion chamber 16, and the spark plug 20 has a function of igniting the air-fuel mixture sucked into the combustion chamber 16 from the intake passage 12 by the spark discharge. Combustion energy generated when the air-fuel mixture is ignited by spark discharge is converted into kinetic energy via the piston 22. On the other hand, the air-fuel mixture subjected to combustion is discharged from the exhaust passage 26 when the exhaust valve 24 is opened.

  The kinetic energy extracted via the piston 22 is output as rotational energy of the crankshaft 30 to drive wheels (not shown) via the transmission 32. The crankshaft 30 is configured to be given initial rotation by a starter 31 in addition to being given rotational energy using the kinetic energy. The transmission 32 is operated via a shift lever 34 as a gear ratio command means from the user.

  The intake valve 18 and the exhaust valve 24 are opened and closed by the rotation of camshafts 38 and 40 that are mechanically connected to the crankshaft 30 and to which the torque of the crankshaft 30 is applied.

  A crank angle sensor 36 for detecting the rotation angle is provided in the vicinity of the crankshaft 30, and a cam angle sensor 42 a for detecting the rotation angle is provided in the vicinity of the camshafts 38 and 40. 42b is provided. Here, the crank angle sensor 36 and the cam angle sensors 42a and 42b are all MRE sensors. The crank angle sensor 36 outputs a signal corresponding to the presence or absence of protrusions formed at equal intervals on the rotor that rotates integrally with the crankshaft 30. On the other hand, the cam angle sensors 42a and 42b output signals according to the presence or absence of protrusions formed at equal intervals on the rotor that rotates integrally with the cam shafts 38 and 40, respectively. The crank angle sensor 36 has a function of discriminating between forward rotation and reverse rotation, and the output voltage width differs between forward rotation and reverse rotation.

  Here, the protrusions formed on the rotor that rotates integrally with the crankshaft 30 are provided at intervals of “6 ° CA”, and have a toothless portion in which the interval of the protrusions at one place is increased. is doing. This determines the reference position (reference crank angle) of the rotation angle of the crankshaft 30, and the output signal of the crank angle sensor 36 outputs the reference signal at this missing tooth portion.

  On the other hand, the protrusion formed on the rotor that rotates integrally with the cam shaft 38 and the protrusion formed on the rotor that rotates integrally with the cam shaft 40 correspond to different crank angles. It is. As a result, the cam angle having phase information at intervals shorter than one rotation of the crank angle can be detected by the outputs of the pair of cam angle sensors 42a and 42b. This is shown in detail in the right part of the figure. Here, the column of the crank angle sensor 36 indicates the number of units (1 unit = 5) of the rotor protrusions from the reference position. The columns of the cam angle sensors 42a and 42b show these outputs. That is, for example, when the output of the cam angle sensor 42a is logic “H” and the output of the cam angle sensor 42b becomes a rising edge, the crank angle corresponds to the protrusion of “1 unit = fifth” from the reference position. To do. Further, for example, the crank angle when the output of the cam angle sensor 42a becomes a rising edge and the output of the cam angle sensor 42b becomes logic “L” corresponds to the protrusion of “21 units = 105th” from the reference position. To do. Thus, the output of the cam angle sensors 42a and 42b is the accurate phase information (rotation angle within 720 ° CA) with one cycle of 4 strokes (720 ° CA) at the timing when either one of the edges is detected. Information).

  The electronic control device (ECU 50) is a control device that controls the internal combustion engine 10 and controls the control amount (torque, rotational speed, exhaust characteristics, etc.). This control is performed by taking in output signals from the brake sensor 52 for detecting the brake operation by the user and the accelerator sensor 54 for detecting the accelerator operation, in addition to the crank angle sensor 36 and the cam angle sensors 42a and 42b. In order to control the control amount, the ECU 50 performs a process of calculating a crank counter CN as data (phase data) having the phase information based on the output signal of the crank angle sensor 36.

  FIG. 2 shows the procedure of the count-up process of the crank counter CN. This process is repeatedly executed by the ECU 50 at a predetermined cycle, for example.

  In this series of processing, first, in step S10, the output of the crank angle sensor 36 is acquired. Specifically, the ECU 50 is provided with a low-pass filter circuit for removing the high-frequency component of the output of the crank angle sensor 36, and obtains the output of the crank angle sensor 36 processed by the low-pass filter circuit. Here, the low-pass filter circuit is for removing high-frequency noise. Here, processing for removing high-frequency noise corresponding to an unexpectedly high rotational speed as the rotational speed of the internal combustion engine 10 is performed. In a succeeding step S12, it is determined whether or not an output edge of the crank angle sensor 36 after the low-pass filter process is detected. If an edge is detected, it is determined in step S14 whether or not the rotation is forward from the output voltage. If it is forward rotation, the crank counter CN is added (step S16), and if it is reverse rotation, the crank counter CN is subtracted (step S18).

  When the processes in steps S16 and S18 are completed, in step S20, the crank counter CN is normalized so that “720 ° CA” is maximized so that the periodic signal has “720 ° CA” as one cycle. Process. This can be done by initializing the crank counter CN in units of “720 ° CA”. Accordingly, the crank counter CN has “720 ° CA” as one cycle, and the phase information is appropriately expressed. Therefore, fuel injection control and ignition control can be performed by using the crank counter CN. Note that the crank counter CN outputs the reference signal once when the internal combustion engine 10 is started, in cooperation with the outputs of the cam angle sensors 42a and 42b, when the reference signal is output at this time during the four strokes. It is reset when processing (cylinder discrimination processing) for specifying which of the two timings is performed. As a result, the crank counter CN becomes phase data representing the phase information. If the reference signal is detected by the crank angle sensor 36 after the cylinder discrimination process, the value of the crank counter CN is appropriately corrected based on the reference signal. At this time, the cam angle sensor 42a is corrected. , 42b are not used.

  The ECU 50 further has a function of performing so-called idle stop control that automatically stops the internal combustion engine 10 when a predetermined stop condition is satisfied and restarts the internal combustion engine 10 when a predetermined restart condition is satisfied. Here, whether or not a predetermined stop condition or a predetermined restart condition is satisfied is determined based on the operation state of the shift lever 34, the brake sensor 52, the accelerator sensor 54, or the like. FIG. 3 shows a procedure of processing relating to restart from automatic stop. This process is repeatedly executed at a predetermined cycle, for example.

  In this series of processes, first, in step S30, it is determined whether or not the internal combustion engine 10 is automatically stopped. If it is determined that the automatic stop has occurred, it is determined in step S32 whether or not a restart condition is satisfied. Here, as the restart condition, for example, an operation to the brake release side by the user can be considered. If it is determined that there is a restart request, it is determined in step S34 whether the engine speed NE is equal to or lower than a predetermined speed α. This process is for determining whether or not to apply initial rotation to the crankshaft 30 by the starter 31. If an affirmative determination is made in step S34, initial rotation is applied to the crankshaft 30 by the starter 31 in step S36. When the process of step S36 is completed or when a negative determination is made at step S34, the fuel injection control based on the crank counter CN is started at step S38.

  Here, the crank counter CN can be updated even if the internal combustion engine 10 is automatically stopped. This is because the crank angle sensor 36 is an MRE sensor and the rotation angle can be detected even when the crankshaft 30 is stopped. For this reason, even during the restart process of the internal combustion engine 10, it is considered that fuel injection control and ignition control can be performed by extracting phase information from the crank counter CN without waiting for completion of the cylinder discrimination process. . However, the phase information of the crank counter CN may be reduced in reliability due to extremely low speed rotation such as the crankshaft 30 being stopped. The reason is that even when the crankshaft 30 is stopped, if the edge of the protrusion formed on the rotor is located at the center of the surface of the crank angle sensor 36 that faces the rotor, the crank angle sensor 36 is the MRE sensor. Depending on the nature of this, there is a possibility of outputting a signal similar to that at the time of rotation.

  FIG. 4 shows measurement data of the output of the crank angle sensor 36 when the edge of the protrusion formed on the rotor is located at the center of the surface of the crank angle sensor 36 that faces the rotor. As shown in the drawing, the crank angle sensor 36 continues to update the crank counter CN in order to output a signal similar to that at the time of rotation.

  In order to avoid the adverse effects caused by such a phenomenon as much as possible, in this embodiment, as shown in FIG. 1, the edge of the protrusion formed on the rotor is positioned at the center of the surface of the crank angle sensor 36 facing the rotor. The protrusions of these three rotors do not occur at the same time as the situation where the edge of the protrusion formed on the rotor is located at the center of the surface of the cam angle sensors 42a, 42b facing the rotor. The layout of the part is set. However, even in this case, the phenomenon itself shown in FIG. 4 cannot be avoided. If the phase information extracted from the crank counter CN is incorrect information, there is a concern that the internal combustion engine 10 may be deteriorated by performing fuel injection control or ignition control based on this information.

  In order to avoid such a situation, it is conceivable to allow the fuel injection control and the ignition control after waiting for the cylinder discrimination process to be completed upon restart. However, in this case, the time required for the restart varies greatly depending on the stop crank angle immediately before the restart, and as a result, the response time from the driver's operation of releasing the brake to the actual movement of the vehicle varies greatly. .

  Therefore, in the present embodiment, fuel injection control and ignition control are performed in the manner shown in FIG. 5 during the restart process. This process is repeatedly executed by the ECU 50 at a predetermined cycle, for example.

  In this series of processing, it is first determined in step S100 whether or not there is a restart request using the starter 31. This process determines whether or not it is during the process of step S36 of FIG. If an affirmative determination is made in step S100, in step S200, data having phase information (crank angle collation data CD) is calculated from the output signals of the cam angle sensors 42a and 42b. This process is the process shown in FIG.

  That is, based on the relationship shown in the upper right table of FIG. 1, the output of the cam angle sensor 42a is logic “H” at the timing when the output of the cam angle sensor 42b becomes a rising edge (step S202: Yes). In this case, the crank angle verification data CD is set to “1” (step S206), and when the output of the cam angle sensor 42a is logic “L”, the crank angle verification data CD is set to “9” (step S206). S208). At the timing when the output of the cam angle sensor 42b becomes a falling edge (step S210: Yes), if the output of the cam angle sensor 42a is logic "H", the crank angle verification data CD is set to "17". (Step S214). At the timing when the output of the cam angle sensor 42a becomes a rising edge (step S216: Yes), if the output of the cam angle sensor 42b is logic “H”, the crank angle verification data CD is set to “13”. (Step S220) If the output of the cam angle sensor 42b is logic “L”, the crank angle collation data CD is set to “21” (Step S222). Further, at the timing when the output of the cam angle sensor 42a becomes a falling edge (step S224: Yes), when the output of the cam angle sensor 42b is logic “H”, the crank angle verification data CD is set to “5”. (Step S228).

  When the process in FIG. 6 is completed, the process proceeds to step S300 in FIG. In step S300, the reliability of the crank counter CN is evaluated. This process is the process shown in FIG.

  In this series of processing, first, in step S300, it is determined whether or not it is the timing when the edges of the cam angle sensors 42a and 42b occur. This process is for identifying the timing at which the phase information indicated by the crank angle collation data CD indicates an accurate crank angle regardless of the accuracy of the protrusion interval of the rotor that rotates integrally with the camshafts 38, 40. is there. If an affirmative determination is made in step S300, it is determined in step S302 whether the degree of deviation between the crank counter CN and the crank angle verification data CD is less than or equal to a predetermined value (the absolute value of the difference between the two is less than or equal to a predetermined value β). This process is for evaluating the reliability of the crank counter CN. Here, the predetermined value β for evaluating the reliability may not be zero. However, it is desirable to set it below the minimum unit of the crank counter CN.

  If an affirmative determination is made in step S302, it is determined in step S304 that the reliability of the crank counter CN is high. On the other hand, if a negative determination is made in step S302, it is determined in step S306 that the reliability of the crank counter CN is low.

  When the process shown in FIG. 7 ends, the process proceeds to step S400 in FIG. In step S400, it is determined whether or not it is determined that the reliability of the crank counter CN is high. If it is determined that the reliability is high, both fuel injection control and ignition control are permitted in step S500. On the other hand, if a negative determination is made in step S400, ignition control is prohibited in step S600. This process is a measure for avoiding a situation that causes deterioration of the internal combustion engine 10 such as reverse rotation of the internal combustion engine 10 due to ignition at an inappropriate ignition timing. In subsequent step S700, it is determined whether or not the number of injections accompanying the restart request is equal to or less than a predetermined number Nth. Here, the predetermined number of times Nth is set to “1” or more. If a positive determination is made in step S700, injection control is permitted in step S800. On the other hand, in step S900, the injection control is prohibited.

  Thus, when ignition control is prohibited, ignition control is started after the reliability of the crank counter CN is increased. That is, the ignition control is started after the crank counter CN is reset by the cylinder discrimination process. FIG. 8 shows a processing procedure of cylinder discrimination processing. This process is executed by the ECU 50 when the internal combustion engine 10 is started.

  In this series of processes, it is determined in step S40 whether or not the cylinder discrimination process has not been completed at the time of the current engine start. If it is determined that the cylinder discrimination processing has not yet been completed, the output of the crank angle sensor 36 is acquired in step S42. When a reference signal is output from the crank angle sensor 36 (step S44), cylinder discrimination processing is performed in consideration of the outputs of the cam angle sensors 42a and 42b. Thereby, the crank counter CN is updated so as to express the phase information specified based on the outputs of the cam angle sensors 42a and 42b and the reference signal. When the process of step S46 is completed, in step S48, the reliability of the crank counter CN is updated to an evaluation that the reliability is high.

  FIG. 9 shows a case where the crank counter CN does not have the correct phase information, particularly when the restart condition is satisfied, among the restart processes according to the present embodiment. Specifically, FIG. 9A shows the transition of the output of the crank angle sensor 36, FIG. 9B shows the transition of the crank counter CN, and FIG. 9C shows the reliability of the crank counter CN. An evaluation result is shown and the possibility of ignition control is shown in Drawing 9 (d).

  As shown in the drawing, when noise is mixed in the output of the crank angle sensor 36 after the internal combustion engine 10 is stopped by the automatic stop process, the value of the crank counter CN changes and deviates from a value representing correct phase information. Thereafter, when the restart condition is satisfied, the value of the crank counter CN is different from the value of the crank angle collation data CD, so that it is determined that the reliability of the crank counter CN is low, and ignition control is prohibited. Thereafter, the cylinder counter process is performed to reset the crank counter CN, so that the reliability of the crank counter CN is improved and the ignition control is permitted. It should be noted that the period from the time when the restart condition is satisfied to the time when the crank counter CN and the crank angle collation data CD are compared is preferably handled as a low reliability of the crank counter CN.

  According to such a series of processes, the restart process can be completed as quickly as possible. That is, if the reliability of the crank counter CN is high, both the fuel injection control and the ignition control are permitted, so that the restart is performed most rapidly. On the other hand, even if the reliability of the crank counter CN is low, the restart can be performed as quickly as possible by permitting the injection control up to a predetermined number of times. That is, when the fuel injection control is also prohibited, when the reliability of the crank counter CN is increased by the processing shown in FIG. 8, the intake stroke in the cylinder that reaches the ignition timing earliest after that time. If it has passed, there is a possibility that the supply of the air-fuel mixture to the combustion chamber 16 will not be in time even if ignition control in that cylinder can be performed. In contrast, in the present embodiment, by permitting the fuel injection control a predetermined number of times, the combustion control can be started as early as possible with respect to the timing at which the reliability of the crank counter CN is increased.

  The predetermined number Nth is set based on the number of injection timings that occur within a period that is allowed as a period required for recovery of reliability when the value of the crank counter CN is not accurate when the restart condition is satisfied. The

  According to the embodiment described in detail above, the following effects can be obtained.

  (1) When starting the restart process of the internal combustion engine 10, based on the comparison between the crank counter CN and the crank angle verification data CD, if it is determined that the reliability of the crank counter CN is low, ignition control is prohibited and the fuel Regarding the injection control, fuel injection of a predetermined number of times Nth was permitted regardless of the reliability evaluation. As a result, it is possible to suitably avoid a situation in which the internal combustion engine 10 is burdened by ignition in an inappropriate phase. Moreover, by permitting the fuel injection for the restart process Nth a predetermined number of times, it is possible to avoid a situation where the fuel injection is not in time even when the reliability is recovered immediately before the ignition control. For this reason, the restart process can be performed as quickly as possible.

  (2) When it is determined that the reliability of the crank counter CN is low, the crank counter CN is updated using the cylinder determination process, and the evaluation of the reliability is updated to the high evaluation. Thereby, ignition control can be performed thereafter.

  (3) An MRE sensor was used as the crank angle sensor 36. As a result, depending on the arrangement with the protrusions of the rotor to be detected, even if the rotor is stopped, a signal when the rotor is rotating may be output. The utility value of the processing to be evaluated is particularly great.

  (4) When the edge of the protrusion of the rotor that is the detection target is located at the center of the crank angle sensor 36, the edge of the protrusion of the rotor that is the detection target is located at the center of the cam angle sensors 42a and 42b. It was set not to be located. Thereby, when both the crank angle sensor 36 and the cam angle sensors 42a and 42b are stationary, it is possible to preferably avoid that both sensors erroneously detect the rotation of the detection target.

(Second Embodiment)
Hereinafter, the second embodiment will be described with reference to the drawings with a focus on differences from the first embodiment.

  In this embodiment, when it is evaluated that the reliability of the crank counter CN is low, the crank counter CN is corrected to the value of the crank angle collation data CD.

  FIG. 10 shows a processing procedure for evaluating the reliability of the crank counter CN according to the present embodiment. In FIG. 10, the same steps as those shown in FIG. 7 are given the same step numbers for the sake of convenience.

  As shown in the figure, in this series of processing, if it is determined in step S306 that the reliability of the crank counter CN is low, a flag (correction request flag) indicating that a request for correcting the crank counter CN has occurred in step S308. Fc) is turned on.

  FIG. 11 shows the procedure of the correction process of the crank counter CN according to the present embodiment. This process is repeatedly executed by the ECU 50 at a predetermined cycle, for example.

  In this series of processing, first, in step S50, it is determined whether or not the correction request flag Fc is on. If it is determined to be on, it is determined in step S52 whether or not it is the timing at which one of the cam angle sensors 42a and 42b occurs. This process determines whether or not it is the update timing of the crank angle collation data CD (the timing at which the crank angle becomes an accurate value). If an affirmative determination is made in step 52, the crank counter CN is corrected to coincide with the crank angle collation data in step S54, the evaluation is updated to the effect that the reliability of the crank counter CN is high, and the correction request flag Fc is turned off. And

  FIG. 12 shows a case where the crank counter CN does not have correct phase information, particularly when the restart condition is satisfied, among the restart processes according to the present embodiment. FIGS. 12A to 12D correspond to the previous FIGS. 9A to 9D.

  As shown in the drawing, when noise is mixed in the output of the crank angle sensor 36 after the internal combustion engine 10 is stopped by the automatic stop process, the value of the crank counter CN changes and deviates from a value representing correct phase information. Thereafter, when the restart condition is satisfied, the value of the crank counter CN is different from the value of the crank angle collation data CD, so that it is determined that the reliability of the crank counter CN is low, and ignition control is prohibited. Then, at the change timing of the crank angle collation data CD immediately after that, the crank counter CN is corrected and its reliability is increased, whereby the ignition control is permitted.

  Since the cylinder discrimination process is also performed in this embodiment, the crank counter CN may be updated by the cylinder discrimination process prior to the processes of steps S52 and S54. Thus, in the present embodiment, there are two cases where the crank counter CN is updated (corrected) in consideration of the outputs of the cam angle sensors 42a and 42b. However, when the crank counter CN is updated, the output of the cam angle sensors 42a and 42b is taken into account only at the time of starting, and only once or twice at the time of starting one.

  According to the present embodiment described above, the following effects can be obtained in addition to the effects (1), (3), and (4) of the first embodiment.

  (5) When the reliability of the crank counter CN is low, the crank counter CN is corrected by the crank angle verification data CD that updates the phase information at intervals shorter than one rotation of the crank angle. As a result, in general, it is possible to correct the phase data earlier than in the case of using the detection of the reference position.

(Other embodiments)
Each of the above embodiments may be modified as follows.

<About cam angle detection means>
The cam angle detection means is not limited to one provided with a pair of sensors having different output signals with respect to the cam shaft rotation angle. For example, three or more sensors may be provided. Further, for example, a single rotor provided on a single cam shaft and a single sensor provided near the rotor may be provided. Even in such a case, for example, by setting the height of the protrusion to two stages, a means capable of detecting the rotation angle of the camshaft at an interval shorter than one rotation of the crankshaft can be configured. .

  However, the cam angle detection means is not limited to a means that can detect the rotation angle of the camshaft at intervals shorter than one rotation of the crankshaft. For example, even if the rotation angle of the camshaft can be detected at intervals of one rotation of the crankshaft, it is possible to use the output of the cam angle detection means in evaluating the reliability of the crank counter (phase data). It is valid.

  The cam angle detection means is not limited to one provided with an MRE sensor.

<Crank angle detection means>
The crank angle detection means is not limited to one capable of detecting the rotation angle every “6 ° CA”. Further, the forward rotation and the reverse rotation are not limited to means for detecting based on the absolute value of the output voltage of the sensor, but may be means for detecting the output frequency of the sensor, for example.

  In addition, the sensor is not limited to the one provided with the MRE sensor, but may be any sensor that can detect the rotation angle even when the rotation speed of the detection target is zero.

  Furthermore, the reference position is not limited to that which can be detected.

<About phase data (crank counter)>
The phase data is not limited to one having an angular interval larger than the minimum rotational angle interval detectable by the crank angle detecting means as one unit. For example, it may be a counter value having a minimum detectable rotation angle interval as one unit. Further, for example, an angular interval smaller than the minimum detectable rotation angle interval may be one unit. This phase data can be calculated by interpolation processing based on the crank angle detected from the output of the crank angle sensor and the rotational speed of the crankshaft.

<Phase data correction means>
The means for correcting the phase data is not limited to the one corrected at the edge timing of the output of the cam angle sensor immediately after the timing when the reliability of the crank counter CN is determined to be low, or during the cylinder discrimination process. For example, it may be the timing when the output of the cam angle sensor becomes the second edge from the timing when it is determined that the reliability of the crank counter CN is low.

<Measuring means for reliability of phase data>
In each of the above embodiments, the evaluation was made that the reliability of the phase data was high at the timing of correcting the phase data, but the present invention is not limited to this. For example, in the second embodiment, after the phase data correction process, it may be updated to an evaluation that the reliability is high at the first timing when the output edge of the cam angle sensor is detected.

  In the second embodiment, the value of the crank counter CN coincides with the crank angle verification data CD at the edge timing of the output of the cam angle sensor immediately after the timing when the reliability of the crank counter CN is determined to be low. In this case, the evaluation that the reliability of the crank counter CN is high may be revised.

  Further, the evaluation of the reliability of the phase data is not limited to that performed only when a restart request using the starter 31 is requested. However, it is desirable to perform the evaluation when it is determined that the internal combustion engine has stopped, such as only when it is determined that the internal combustion engine has stopped. Here, as a restart process that does not use the starter 31 even when the internal combustion engine is stopped, for example, a case where an initial rotation is applied to the internal combustion engine by releasing the brake of the vehicle on a downhill can be considered. Particularly in such a case, the edge of the protrusion formed on the rotor is located at the center of the surface of the crank angle sensor 36 that faces the rotor, and the center of the surface of the cam angle sensors 42a and 42b that faces the rotor. If the edge of the protrusion formed on the rotor is located in the part, there is a concern that the starting process is performed assuming that the crankshaft 30 is rotating despite being actually stopped. In this case, the reliability of the crank counter CN may not be properly evaluated. Therefore, it is particularly effective to arrange the three rotors in the manner illustrated in the above embodiments. .

<Others>
The geometric arrangement setting of the detection target of the crank angle sensor 36 and the detection target of the cam angle sensors 42a and 42b is not limited to that exemplified in the first embodiment. Even if it does not set it as such a setting, the effect of said (1)-(3) of the said 1st Embodiment can be acquired.

  The internal combustion engine is not limited to the intake port type, but may be, for example, a cylinder injection type. However, in this case, it is desirable to set the predetermined number Nth used in the process of step S700 in FIG. 5 to a value smaller than that in the above embodiment.

  The control device having the function of performing the automatic stop process and the restart process is not limited to the one having only the internal combustion engine as the in-vehicle main machine. For example, even in the case of a so-called hybrid vehicle that uses an electric motor as an in-vehicle main engine, the application of the present invention is effective if the rotation angle can be zero prior to the restart process of the internal combustion engine.

  DESCRIPTION OF SYMBOLS 10 ... Internal combustion engine, 36 ... Crank angle sensor, 42a, 42b ... Cam angle sensor, 50 ... ECU.

Claims (7)

In a control device for a spark ignition type internal combustion engine having a function of performing an automatic stop process and a restart process of a spark ignition type internal combustion engine employing a four-stroke cycle,
The detection result of the crank angle detection means for detecting the crank angle of the internal combustion engine is input, and phase data which is data that is referred to in both fuel injection control and ignition control with four strokes of the internal combustion engine as one cycle, A calculation means for continuously calculating including a period during which combustion control of the internal combustion engine is stopped by the automatic stop process;
Evaluation means for evaluating the reliability of the phase data based on the comparison between the detection result of the cam angle detection means for detecting the rotation angle of the cam shaft of the internal combustion engine and the phase data;
Injection control means for executing the first fuel injection for the restart process regardless of the output of the evaluation means;
A control device for a spark ignition type internal combustion engine, comprising: prohibiting means for prohibiting ignition control of the internal combustion engine when the evaluation means determines that the reliability of the phase data is low.   2. The spark ignition type internal combustion engine according to claim 1, further comprising a limiting unit configured to limit a number of times of fuel injection for the restart process when the evaluation unit determines that the reliability of the phase data is low. Engine control device. When the evaluation means determines that the reliability of the phase data is low, the evaluation means further comprises correction means for correcting the phase data based on the detection result of the cam angle detection means,
The evaluation means changes the evaluation of the reliability of the phase data to an evaluation that the reliability of the phase data is high by correcting the phase data by the correction means. 3. A control device for a spark ignition internal combustion engine according to 1 or 2. The cam angle detection means is capable of detecting the rotation angle of the cam shaft at an interval shorter than one rotation of the crank angle,
4. The control apparatus for a spark ignition type internal combustion engine according to claim 3, wherein the correction means corrects the phase data based on phase information included in an output signal of the cam angle detection means. The crank angle detecting means has a function of detecting a reference crank angle,
Further comprising cylinder discrimination means for performing cylinder discrimination based on detection of the reference crank angle by the crank angle detection means and detection result of the cam angle detection means;
4. The control apparatus for a spark ignition type internal combustion engine according to claim 3, wherein the correction means corrects the phase data based on cylinder discrimination by the cylinder discrimination means.   The control device for a spark ignition type internal combustion engine according to any one of claims 1 to 5, wherein the crank angle detection means includes an MRE sensor. The cam angle detection means includes an MRE sensor,
When the edge of the detection target is located at the center of the MRE sensor included in the crank angle detection unit, the detection target edge is not positioned at the center of the MRE sensor included in the cam angle detection unit. 7. The control device for a spark ignition type internal combustion engine according to claim 6, wherein the control device is set.

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