JP4508225B2 - Start control device for internal combustion engine - Google Patents

Description

  The present invention relates to an internal combustion engine start control device, and more particularly, to an internal combustion engine start control device capable of determining whether or not a start means for starting an internal combustion engine has failed.

  In vehicles, from the viewpoints of energy saving and carbon dioxide emission reduction, it is advancing to install an idling stop function that automatically stops an internal combustion engine when the vehicle stops.

  Also, as a starting means suitable for vehicles equipped with an idling stop function, the pinion gear of the starter motor and the ring gear provided on the crankshaft are always meshed, and the rotation is transmitted to the crankshaft of the internal combustion engine. There is known a one-way clutch that allows and prevents transmission of power from a crankshaft to a starter motor (see, for example, Patent Document 1).

  Further, in a vehicle having an idling stop function, in order to improve the startability of the internal combustion engine, the cylinder that performs fuel injection and ignition at the start of the internal combustion engine is quickly determined, and the fuel is injected and ignited in the cylinder. What performs control is known (for example, refer to patent documents 2).

  The one described in Patent Document 2 is provided on the crankshaft, an NE sensor (crank angle sensor) and a G sensor (cam position sensor) for detecting the crank angle of the internal combustion engine, the top dead center (TDC) of each cylinder. , A first rotating body having first teeth formed at equal intervals (for example, 10 ° CA interval) and one first missing tooth portion, and a second rotating shaft provided on the camshaft. And a second rotating body having a second missing tooth portion constituted by a tooth and an outer peripheral surface other than the second tooth.

  The NE sensor outputs a pulse signal corresponding to the first tooth every 10 ° CA when the first rotating body rotates with the rotation of the crankshaft, and becomes a reference corresponding to the first missing tooth portion. A reference position signal is output, and the G sensor outputs a pulse signal corresponding to the second tooth every 360 ° CA, for example.

  Then, based on the pulse signals output from these NE sensor and G sensor, the crank angle and the top dead center (TDC) of each cylinder are obtained. For example, when the NE sensor outputs a pulse signal corresponding to the first missing tooth portion, the time when the pulse signal corresponding to the next first tooth is output is the first cylinder # 1 or 4 The TDC of the No. cylinder # 4 is determined, and 180 ° CA (18 pulses) after the TDC is determined as the TDC of the No. 3 cylinder # 3 or the No. 2 cylinder # 2.

  However, this alone cannot determine whether the corresponding cylinder is the first cylinder # 1 or the fourth cylinder # 4. Therefore, when the G sensor outputs a pulse signal corresponding to the teeth of the second rotating body. Is determined to correspond to the first cylinder # 1.

  Since the stop position of the crankshaft and the camshaft can be known based on each pulse signal output from the NE sensor and the G sensor before the start means is started (when idling is stopped), the crankshaft and cam Based on the stop position of the shaft, the cylinder that performs fuel injection or ignition is discriminated, and the fuel injection or ignition is performed immediately in any cylinder immediately after the crankshaft starts rotating at the start of operation of the starting means. The start of the internal combustion engine can be completed.

  On the other hand, the starting means provided with the above-described one-way clutch allows the rotation to be transmitted to the crankshaft of the internal combustion engine and prevents the power from the crankshaft from being transmitted to the starter motor. Therefore, the stop position of the crankshaft and the camshaft can be more easily known on the basis of each pulse signal output from the NE sensor and the G sensor. It has become.

  That is, immediately before the internal combustion engine is stopped, the piston in the compression process is pushed back by the pressure of the air in the cylinder whose pressure has been increased near the top dead center and cannot exceed the top dead center. Arise.

However, in the starting means provided with the one-way clutch, since the power from the crankshaft can be prevented from being transmitted to the starter motor, the starting means and the crankshaft are locked by the one-way clutch. It is possible to prevent reverse rotation.
JP 2005-9430 A Japanese Patent Laid-Open No. 11-13528

  In the starting means provided with such a conventional one-way clutch, when a situation in which the reverse rotation of the crankshaft cannot be prevented due to some abnormality occurring in the one-way clutch, the NE is stopped immediately before stopping. Since the signal output from the sensor becomes an output signal including forward rotation and reverse rotation of the crankshaft, the stop position of the crankshaft cannot be accurately detected.

  For this reason, at the start of operation of the starting means, other cylinders other than the cylinder that should originally be ignited may be subjected to a load on the internal combustion engine, and it is possible to accurately determine the failure of the starting means. desired.

  The present invention has been made to solve the above-described conventional problems, and an object of the present invention is to provide a start control device for an internal combustion engine that can accurately determine the presence or absence of a failure of the start means.

In order to achieve the above object, the internal combustion engine start control device according to the present invention includes (1) a starter motor and the power of the starter motor transmitted to the crankshaft of the internal combustion engine, and the start of the power from the crankshaft. A one-way clutch for preventing transmission to the motor, starting means for starting the internal combustion engine, crank angle detecting means for detecting a crank angle of the crankshaft, and a reference set for the crank angle Reference position detection means for detecting the position, crank angle storage means for storing the crank angle at the time when the rotation of the crankshaft is stopped, and a target rotation angle of the crank angle determined based on the crank angle stored in the crank angle storage means The target rotation angle calculating means for calculating the engine and the starting means start the internal combustion engine Is after, when the crank shaft from the time of stop of the rotation of the crankshaft rotates by the target rotation angle, when the reference position is determined as not being detected by the reference position detecting means, said starting means There is constructed from that a determining failure determining means as being faulty.

  With this configuration, the target rotation angle of the crank angle from the crank angle stored when the crankshaft is stopped to the reference position is calculated, and after the start of the internal combustion engine is started by the starting means, the crankshaft is stopped after the crankshaft is stopped. By determining whether or not the reference position has been detected when the shaft rotates by the target rotation angle, it is possible to determine whether or not the crankshaft has been driven in reverse due to some abnormality occurring in the one-way clutch or the like. Thus, it is possible to accurately determine whether or not the starting means has failed.

  In the internal combustion engine start control device described in (1) above, (2) when the stop condition of the internal combustion engine is satisfied, the fuel injection control and the ignition control are stopped, and the start of the internal combustion engine is started by the start means. Then, an internal combustion engine control means for executing fuel injection control and ignition control for the cylinder is provided, and the failure determination means is configured to rotate the crankshaft by the target rotation angle from when the crankshaft is stopped. When it is determined that the reference position has been detected by the reference position detection means, the internal combustion engine control means determines the cylinder to be ignited and performs fuel injection control and ignition for the cylinder to be ignited. Control is performed, and when the failure determination means rotates the crankshaft by the target rotation angle from when the rotation of the crankshaft is stopped, If it is determined that the reference position is not detected by the reference position detection means, the internal combustion engine control means stops performing fuel injection control and ignition control on the cylinder that is first determined to be ignited. It consists of what to do.

With this configuration, if the reference position is detected when the crankshaft rotates by the target rotation angle from when the crankshaft stops rotating, it is determined that the starting means is normal and the cylinder to be ignited promptly Thus, fuel injection control and ignition control can be performed on the cylinder to be ignited, and the startability of the internal combustion engine can be improved.
Also, if the reference position is not detected when the crankshaft rotates by the target rotation angle from when the crankshaft stops rotating, it is highly likely that the starter has failed and the crankshaft has rotated backward. Since the fuel injection control and the ignition control for the cylinder determined to be ignited are stopped, it is possible to prevent erroneous ignition after the internal combustion engine is started, and the load on the internal combustion engine increases. Can be prevented.

  (3) In the internal combustion engine start control device according to (2), (3) the failure determination means detects the reference position when the crankshaft rotates by the target rotation angle from when the crankshaft stops rotating. When it is determined that the reference position is not detected by the means, the internal combustion engine control means determines again the cylinder to be ignited based on the reference position detected by the reference position detection means, and performs fuel injection control and It is comprised from what performs ignition control.

  With this configuration, if the reference position is not detected when the crankshaft rotates by the target rotation angle after the crankshaft rotation is stopped after the starter starts the internal combustion engine, the starter Because it is highly possible that the crankshaft has rotated backward due to failure, the cylinder to be ignited is determined again based on the reference position set at the actually detected crank angle, and fuel injection control and ignition control are performed. Therefore, it is possible to accurately determine the cylinder to be ignited and to ignite the cylinder. For this reason, it is possible to accurately determine the cylinder to be ignited even when the starter is out of order, and to prevent erroneous ignition.

  In the internal combustion engine start control apparatus according to any one of the above (1) to (3), (4) the failure determination unit has rotated the crankshaft by the target rotation angle from the time when the crankshaft stopped rotating. Sometimes, when the number of times that the reference position is not detected by the reference position detecting means is continuously determined by a predetermined number of times, a failure of the starting means is notified.

  With this configuration, after the start of the internal combustion engine by the starting means, the reference position is not detected by the reference position detecting means even though the crankshaft has been rotated by the target rotation angle since the crankshaft stopped rotating. When the situation occurs repeatedly, it is possible to notify the driver that the starter has failed by notifying that the starter has definitely failed, and promptly take action. .

  Further, after the start of the internal combustion engine by the starting means, there is a situation in which the reference position is not detected by the reference position detecting means even though the crankshaft has been rotated by the target rotation angle from the time when the rotation of the crankshaft is stopped. If it occurs continuously less than a predetermined number of times, it is determined that the crank angle detection signal is affected by noise and the like, and the failure notification is not performed, so the starting means is continuously used. be able to.

  ADVANTAGE OF THE INVENTION According to this invention, the starting control apparatus of the internal combustion engine which can determine correctly the presence or absence of a failure of a starting means can be provided.

Embodiments of a start control device for an internal combustion engine according to the present invention will be described below with reference to the drawings.
1 to 10 show an embodiment of a start control device for an internal combustion engine according to the present invention.

First, the configuration will be described.
In FIG. 1, a cylinder block 1a of an engine 1 as an internal combustion engine includes four cylinders 2. These cylinders 2 are a first cylinder # 1, a second cylinder # 2, and a third cylinder arranged in order. # 3 and fourth cylinder # 4 are included. In FIG. 1, only the first cylinder # 1 is shown.

  A piston 3 is accommodated in each cylinder 2 so as to be able to reciprocate, and each piston 3 is connected to a crankshaft 8 via a connecting rod 7. The reciprocating motion of the piston 3 is converted into the rotational motion of the crankshaft 8 by the connecting rod 7. The rotational position of the crankshaft 8 is represented by a crank angle (° CA). The cylinder head 1b is fixed to the upper part of the cylinder block 1a. The piston 3 and the cylinder head 1 b define a combustion chamber 4 in each cylinder 2.

  The intake camshaft 13 and the exhaust camshaft 14 are rotatably supported by the cylinder head 1b, and the intake valve 11 and the exhaust valve 12 can reciprocate to the cylinder head 1b so as to correspond to each cylinder 2, respectively. The combustion chamber 4 and the intake passage 9 and the exhaust passage 10 are respectively opened and closed.

  Further, a throttle valve 15 is provided in the intake passage 9, and the throttle valve 15 has its opening degree changed according to the depression amount of an accelerator pedal (not shown).

  The intake camshaft 13 and the exhaust camshaft 14 are connected to the crankshaft 8 by a timing belt 19, and the intake camshaft 13 and the exhaust camshaft 14 rotate once while the crankshaft 8 rotates twice.

  When the intake camshaft 13 and the exhaust camshaft 14 rotate, the intake valve 11 and the exhaust valve 12 are driven by the corresponding intake camshaft 13 and exhaust camshaft 14, respectively. As the intake valve 11 and the exhaust valve 12 are driven, the intake port 16 and the exhaust port 17 are opened and closed at a predetermined timing.

  A variable valve timing mechanism (hereinafter referred to as VVT) 18 for changing the opening / closing timing of the intake valve 11 is provided between the intake camshaft 13 and the timing belt 19, and the VVT 18 is an intake valve. 11 is operated so as to change the rotation phase of the intake camshaft 13 with respect to the crankshaft 8. The VVT 18 is controlled by an ECU 100 including a computer or the like which will be described later.

  Injectors 5 made of electromagnetic valves function as fuel injection means, and are provided in the intake ports 16 so as to correspond to the respective cylinders 2. Each injector 5 injects fuel into the corresponding intake port 16.

  The fuel injection timing and the injection amount are adjusted by the ECU 100 controlling the opening timing and closing timing of the injector 5. In the present embodiment, a sequential injection method in which fuel is sequentially injected into the four cylinders 2 is employed. Of course, it goes without saying that other injection methods may be employed.

  The spark plug 6 is attached to the cylinder head 1b so as to correspond to each cylinder 2, and each spark plug 6 is electrically connected to the ignition coil 50, respectively. The spark plug 6 ignites a mixture of fuel and air supplied from the intake port 16 to the combustion chamber 4 based on the high voltage supplied from the ignition coil 50 and burns the mixture.

  The high voltage generation timing in the ignition coil 50, that is, the ignition timing by the spark plug 6, is adjusted by the ECU 100 controlling the igniter 49.

  Further, the engine 1 is provided with a starter 20 as a starter. The starter 20 includes a starter motor 21 as a starter motor and a starter motor 21 on the crankshaft 8 of the engine 1 as shown in FIG. And a gear train 22 for transmitting the rotation of the motor.

  The gear train 22 includes a starter gear 23 that is driven by the output shaft 21 a of the starter motor 21, and a driven gear 25 that is provided on the support shaft 24 that is provided in parallel with the crankshaft 8 and the starter motor 21 so as to mesh with the starter gear 23. An intermediate gear 27 provided coaxially on a support shaft 24 via a one-way clutch 26 as a clutch, and a crank gear 28 provided so as to rotate integrally with the crankshaft 8 so as to mesh with the intermediate gear 27. I have.

  The gear ratio between the starter gear 23 and the driven gear 25 and between the intermediate gear 27 and the crank gear 28 is transmitted between the respective gears by reducing the rotation from the output shaft 21a side of the starter motor 21 toward the crankshaft 8 side. Is set to Accordingly, in the gear train 22, the rotation is gradually reduced and transmitted to the crankshaft 8. The driven gear 25 can rotate together with the support shaft 24.

  The one-way clutch 26 is configured to allow rotation transmission from the support shaft 24 to the intermediate gear 27 and prevent rotation transmission from the intermediate gear 27 to the support shaft 24. That is, the one-way clutch 26 allows rotation to be transmitted to the crankshaft 8 of the engine 1 and prevents transmission of power from the crankshaft 8 to the starter motor 21.

  FIG. 3 is a diagram showing a specific configuration of the one-way clutch 26. In FIG. 3, the one-way clutch 26 is fitted so as to be in close contact with the inner peripheral surface 27b of the intermediate gear 27, and the one-way clutch 26 is sandwiched between the inner peripheral surfaces 27a and 27c of the intermediate gear 27. 29 and 30 are fitted.

  The bearings 29 and 30 and the one-way clutch 26 are integrally fitted to the support shaft 24 in a state of being incorporated in the intermediate gear 27, and the intermediate gear 27 is fitted from the shaft end 24e side of the support shaft 24. The outer diameters of the outer peripheral surfaces 24a, 24b, and 24c of the support shaft 24 are processed so as to decrease in the order of the outer peripheral surfaces 24a, 24b, and 24c.

  A bearing 32 is press-fitted into the shaft end portion 24 e of the support shaft 24, and the bearing 32 is prevented from coming off by the intermediate gear 27 via a leaf spring 33. The support shaft 24 is rotatably supported by bearings 31 and 32 fitted to the shaft end portions 24d and 24e.

  On the other hand, as shown in FIG. 4, the one-way clutch 26 includes a pair of inner rings 41, an outer ring 42 provided so as to surround the inner ring 41, and a plurality of sprags 43 arranged in a gap between the inner ring 41 and the outer ring 42. The inner ring 41 and the outer ring 42 are arranged coaxially, and a pair of retainers 44 that maintain the posture of the sprags 43 are provided.

  The sprag 43 has a function as a transmission element for switching the transmission direction of the rotation in accordance with the rotational speed of the engine 1, and operates as shown in FIGS. 4 (a) and 4 (b). That is, when the engine 1 is started, the forward rotation R1 is input to the inner ring 41 as shown in FIG. At this time, since the sprag 43 is in contact with both the outer peripheral surface 41a of the inner ring 41 and the inner peripheral surface 42a of the outer ring 42, the forward rotation R2 can be transmitted to the outer ring 42 by the frictional force of the contact surface. it can.

  On the other hand, when the engine 1 is in operation, as shown in FIG. 4B, the rotation of the crankshaft 8 is transmitted to the outer ring 42, and the forward rotation R3 is input. At this time, the sprag 43 receives the centrifugal force and rotates and tilts in the direction of the arrow r1. Since the diagonal length L1 of one of the sprags 43 is shorter than the other length L2, the inclined sprag 43 cannot contact the outer peripheral surface 41a of the inner ring 41.

  Since the outer ring 42 idles around the inner ring 41 together with the sprags 43, transmission of the rotation R3 in the forward direction of the outer ring 42 is prevented. Just before the engine 1 is stopped, the centrifugal force received by the sprag 43 becomes small, so the sprag 43 returns to the posture shown in FIG. As a result, the intermediate gear 27 is locked by the one-way clutch 26 when the vehicle is stopped. Therefore, the starter motor 21 and the crankshaft 8 are also locked by the one-way clutch 26, and it is possible to prevent reverse rotation of the crankshaft 8.

  On the other hand, as shown in FIG. 5, while the crankshaft 8 rotates twice, each engine # 1 to # 4 executes one engine cycle including an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke. . Therefore, the rotation position of the crankshaft 8 is expressed as one cycle of the rotation angle of the crankshaft 8 for two rotations, that is, 0 ° CA to 720 ° CA.

  Further, in the engine 1 of the present embodiment, as shown in FIG. 5, every time the crankshaft 8 rotates by 180 ° CA, the piston 3 in the first cylinder # 1, the piston 3 in the third cylinder # 3, The piston 3 in the fourth cylinder # 4 and the piston 3 in the second cylinder # 2 are sequentially arranged at the top dead center in the compression stroke (simply abbreviated as TDC in FIG. 5).

  In other words, the piston 3 in each cylinder 2 is in a state where the phase is shifted by 180 ° CA in the order of the first cylinder # 1, the third cylinder # 3, the fourth cylinder # 4, and the second cylinder # 2. Reciprocates. Therefore, by identifying the rotational position of the crankshaft 8 in the angle range of 0 ° CA to 720 ° CA, it is possible to determine the stroke position of the piston 3 in each cylinder 2, that is, to determine the cylinder.

  In FIG. 5, the hatched area mainly corresponding to the intake strokes of the cylinders # 1 to # 4 indicates the opening period of the intake valve 11, and the hatched area above it indicates the injection period. The mixture of fuel and air injected into the intake port 16 is introduced into the corresponding cylinder 2 as the intake valve 11 is opened.

  As shown in FIG. 6, the crankshaft 8 is provided with a crank rotor 45, and the crank rotor 45 rotates integrally with the crankshaft 8. A crank angle sensor 46 is provided in the vicinity of the crank rotor 45, and is attached to the cylinder block 1a of the engine 1 so as to face the outer peripheral surface of the crank rotor 45.

  On the outer peripheral surface of the crank rotor 45, 34 protrusions 45a are provided at equal intervals (10 ° CA in the present embodiment). However, only one place on the outer peripheral surface of the crank rotor 45 has an interval between two adjacent projections 45a of 30 ° CA.

  Therefore, the crank rotor 45 has a shape in which two continuous protrusions are deleted from a crank rotor having 36 protrusions at equal intervals. A portion corresponding to the portion from which these two protrusions are deleted is referred to as a missing tooth portion 45b as a reference position for determining the cylinder 2 on the crank rotor 45.

  The crank angle sensor 46 generates one NE pulse signal (crank pulse) each time each projection 45a passes the position facing the crank angle sensor 46 as the crank rotor 45 rotates.

  As the crank angle sensor 46, a semiconductor sensor, for example, a magnetic sensor such as a Hall element and a magnetoresistive element, or various optical sensors can be used. Further, an electromagnetic pickup coil can be used as the crank angle sensor 46.

  The material or shape of the crank rotor 45 is determined so that a pulse can be induced in the applied crank angle sensor 46. Therefore, on the crank rotor 45, an index other than the protrusion 45a, for example, a recess or a hole may be provided in accordance with the type of the applied crank angle sensor 46.

  Further, the NE pulse signal output from the crank angle sensor 46 is output to an ECU (Electric Control Unit) 100, and the ECU 100 performs 10 based on the NE pulse signal input from the crank angle sensor 46. The crank angle in CA increments and the rotation speed of the engine 1 are calculated.

  In addition, when an NE pulse signal having a long interval between the protrusion 45a and the adjacent protrusion 45a is input, the ECU 100 detects the missing tooth 45b and sets the missing tooth 45b as the reference position of the crankshaft 8. The cylinder 2 that performs the fuel injection control and the ignition control is determined based on the reference position.

  In the present embodiment, the crank angle sensor 46 and the ECU 100 constitute crank angle detection means for detecting the crank angle of the crankshaft 8 and reference position detection means for detecting a reference position set to the crank angle.

  As shown in FIG. 7, the intake camshaft 13 is provided with a cam rotor 47, and the cam rotor 47 rotates integrally with the intake camshaft 13. A cam position sensor 48 is provided in the vicinity of the intake camshaft 13, and the cam position sensor 48 is attached to the cylinder head 1 b of the engine 1 so as to face the outer peripheral surface of the cam rotor 47.

  Further, a first protrusion 47a, a second protrusion 47b, and a third protrusion 47c are provided on the outer peripheral surface of the cam rotor 47. The second protrusion 47b and the third protrusion 47c as auxiliary indicators are They are arranged at an angular interval of 180 °.

  In addition, the first projection 47a as a discrimination index used for cylinder discrimination is disposed at an angular interval of 90 ° with respect to the second projection 47b and the third projection 47c, and the first projection 47a. There is no protrusion at a position 180 ° away from the center.

  Each time the first protrusion 47a, the second protrusion 47b, and the third protrusion 47c pass the position facing the cam position sensor 48 as the cam rotor 47 rotates, the cam position sensor 48 generates one NE pulse signal (cam pulse). ).

  As the cam position sensor 48, as with the crank angle sensor 46, for example, a semiconductor sensor such as a magnetic sensor or an optical sensor, or an electromagnetic pickup coil can be used. The material or shape of the cam rotor 47 is also determined so that a pulse can be induced in the applied cam position sensor 48. Therefore, on the cam rotor 47, an index other than the first protrusion 47a, the second protrusion 47b, and the third protrusion 47c, for example, a recess or a hole is provided according to the type of the cam position sensor 48 to be applied. Also good.

  The ECU 100 is composed of a computer including a CPU (Central Processing Unit) 100a, a RAM (Random Access Memory) 100b, and a ROM (Read Only Memory) 100c, and the operating state of the engine 1 according to a program stored in the ROM 100c. Various processes necessary for controlling the system are executed.

  The ECU 100 also includes an input circuit (not shown) to which signals from the crank angle sensor 46 and the cam position sensor 48 are input, and an output circuit (not shown) that outputs drive signals to the injector 5 and the igniter 49. The igniter 49 has a function of controlling the ignition timing by the spark plug 6.

  When the crank rotor 45 rotates together with the crankshaft 8, the crank angle sensor 46 generates a train of crank pulses as shown in FIG. As shown in FIG. 6, one crank pulse is generated every time the crank angle sensor 46 rotates 10 ° CA corresponding to the arrangement of the protrusions 45 a on the crank rotor 45.

  However, since the missing tooth portion 45b on the crank rotor 45 passes once through the crank angle sensor 46 during one rotation of the crank rotor 45, the interval between the crank pulses of the projecting portions 45a before and after the missing tooth portion 45b is determined. A crank pulse that is clearly different from a crank angle pulse of 10 ° CA is input. Therefore, the ECU 100 can detect the passage of the missing tooth portion 45b on the crank rotor 45 based on the input of the crank pulses at intervals of 30 ° CA.

  In other words, the ECU 100 can recognize that the crankshaft 8 is at a specific rotation angle based on the input of crank pulses at 30 ° CA intervals. A period from the generation of the crank pulse having an interval of 30 ° CA to the rotation of the crankshaft 8 by a predetermined angle is set as a determination period G (determination angle range) for determining the cylinder.

  In the present embodiment, the determination period G is a period from the first crank pulse having an interval of 30 ° CA to the generation of the 13th crank pulse, that is, from the detection of the missing tooth portion 45b to the crankshaft 8. Is set to an angle range until it rotates by 120 ° CA.

  On the other hand, when the cam rotor 47 rotates together with the intake camshaft 13, the cam position sensor 48 corresponds to the first protrusion 47a, the second protrusion 47b, and the third protrusion 47c on the cam rotor 47 as shown in FIG. The first cam pulse CP1, the second cam pulse CP2, and the third cam pulse CP3 are generated and output to the ECU 100.

  As shown in FIG. 5, the positional relationship between the crank angle sensor 46 and the cam position sensor 48 and the crank rotor 45 and the cam rotor 47 is set so that the first cam pulse CP1 corresponding to the first protrusion 47a is generated during the determination period G. Has been.

  In addition, while the intake camshaft 13 makes one rotation, the crankshaft 8 rotates twice and the determination period G appears twice. The first cam pulse CP1 as the discrimination cam signal is generated in synchronization with one of the two discrimination periods G that appear while the intake camshaft 13 makes one rotation. Based on whether or not the first cam pulse CP1 is generated during the determination period G, the cylinder position can be determined by specifying the rotational position of the crankshaft 8 during two rotations.

  In the present embodiment, as shown in FIG. 5, when the first cam pulse CP1 is generated during the determination period G, the crank pulse corresponding to the end time of the determination period G is set as the first, and the tenth crank pulse from there. The piston 3 of the first cylinder # 1 is arranged at the top dead center in the compression stroke at the timing when the pulse occurs, that is, after the crankshaft 8 has rotated by 90 ° CA after the determination period G ends.

  On the other hand, when the first cam pulse CP1 is not generated during the determination period G, the fourth crank # is generated at the timing at which the crank pulse corresponding to the end timing of the determination period G is first and the tenth crank pulse is generated therefrom. Four pistons 3 are arranged at the top dead center in the compression stroke.

  When the piston 3 of the first cylinder # 1 is disposed at the top dead center in the compression stroke, the crank counter value CCR used as a value indicating the crank angle is set to “0”. This crank counter value CCR is incremented by “1” every time the crankshaft 8 rotates 30 ° CA, and when it reaches “23”, it again returns to “0”.

  Therefore, based on the crank counter value CCR, the rotational position of the crankshaft 8 during two rotations can be specified, and the stroke position of the piston 3 in each cylinder 2 can be determined, that is, the cylinder can be determined. As a result of the cylinder discrimination, ignition control is performed at the timing when the piston 3 is located at the top dead center.

  In addition, the second cam pulse CP2 corresponding to the second protrusion 47b is generated during the period from the end of the determination period G accompanying the generation of the first cam pulse CP1 until the next detection of the missing tooth portion 45b. Specifically, the second cam pulse CP2 is generated after the intake camshaft 13 rotates 90 ° (corresponding to 180 ° CA) after the first cam pulse CP1 is generated. The third cam pulse CP3 corresponding to the third protrusion 47c is generated during the period from the end of the determination period G not accompanied by the generation of the first cam pulse CP1 until the next detection of the missing tooth portion 45b.

  Specifically, the third cam pulse CP3 is generated after the intake camshaft 13 has rotated 180 ° (corresponding to 360 ° CA) after the generation of the second cam pulse CP2.

  Further, the first cam pulse CP1, the second cam pulse CP2, and the third cam pulse CP3 are all generated by removing the injection prohibition period in all the cylinders # 1 to # 4, so that the first cam pulse CP1, the second cam pulse CP2, It is possible to execute fuel injection for all the cylinders # 1 to # 4 at any timing of generation of the third cam pulse CP3.

  On the other hand, the ECU 100 is supplied with output signals from a throttle sensor 51 that detects the opening of the throttle valve 15 and a shift position sensor 52 that detects the shift position of the shift lever operated by the driver. The ECU 100 receives a signal indicating that the accelerator opening is “0” from the throttle sensor 51 and indicates that the shift position is “neutral position” or “parking position” from the shift position sensor 52. Is input, it is determined that the idling stop condition is satisfied, and the fuel injection control and the ignition control are stopped.

  Note that, as an aspect in which the idling stop condition is satisfied, the vehicle speed may be “0” based on the output signal from the crank angle sensor 46 and the time may be continued for a certain period of time.

  Further, the ECU 100 stores the crank angle of the crankshaft 8 in increments of 10 ° CA when the rotation of the crankshaft 8 is stopped. For example, if the crank angle detected by the crank angle sensor 46 is 50 ° CA, “1” is stored as the crank counter value. In the present embodiment, the ECU 100 constitutes a crank angle storage means.

  Further, in the present embodiment, when the accelerator pedal is operated during idling stop, and a signal indicating that the accelerator opening is not “0” is input from the throttle sensor 51, the idling stop condition is not satisfied. The starter 20 is actuated by determining that it has become.

  Further, the ECU 100 calculates the missing tooth detection target position as a target rotation angle of a predetermined crank angle from the crank angle stored in the RAM 100b.

  Then, after the start of the engine 1 is started by the starter 20, the ECU 100 counts up when the NE pulse signal detected by the crank angle sensor 46 is counted up by a crank angle corresponding to the missing tooth detection target position, that is, When the crankshaft 8 is rotated by the target rotation angle from the time when the rotation of the crankshaft 8 is stopped, it is determined whether or not the missing gear portion 45b is detected by the crank angle sensor 46, thereby determining whether or not the starter 20 has failed. It comes to judge.

  Then, after the start of the engine 1 is started by the starter 20, the ECU 100 determines a cylinder to be ignited based on a determination result of whether or not the starter 20 has failed, and performs fuel injection control on the cylinder to be ignited. And execute ignition control.

  The ECU 100 according to the present embodiment detects the missing tooth portion 45b when the count-up value of the NE pulse signal detected by the crank angle sensor 46 becomes a pulse value corresponding to the missing tooth detection target position. Therefore, it is determined that there is a high possibility that reverse rotation of the crankshaft 8 has occurred due to the failure of the starter 20.

  That is, if an abnormality occurs in the one-way clutch 26 or the like of the starter 20 for some reason, the crankshaft 8 rotates in the reverse direction just before the crankshaft 8 stops when idling stops. It may end up.

  This phenomenon is caused by the reverse rotation of the crankshaft 8 because the piston 3 in the compression process is pushed back by the pressure of air in the cylinder 2 whose pressure is increased near the top dead center and cannot exceed the top dead center. Because of.

  In this case, the crank angle stored when the crankshaft 8 is stopped is different from the actual crank angle. When the cylinder is discriminated based on this crank angle and the fuel injection control and the ignition control are executed, a false ignition occurs. There is a fear.

  Therefore, the ECU 100 according to the present embodiment does not detect the missing tooth portion 45b when the count-up value of the NE pulse signal detected by the crank angle sensor 46 becomes a pulse value corresponding to the missing tooth detection target position. It is determined that there is a high possibility that the starter 20 has failed and reverse rotation of the crankshaft 8 has occurred, and fuel is injected into the cylinder that should be ignited originally, that is, the cylinder that has been determined to be ignited first. Control to stop performing control and ignition control is performed.

  Further, when the ECU 100 determines that the starter 20 has failed, when the crank angle sensor 46 actually detects the missing tooth portion 45b, the ECU 100 resets the missing tooth portion 45b to the reference position and ignites again. The fuel injection control and the ignition control are executed by determining the cylinder to be performed.

  Further, the ECU 100 determines a predetermined number of times that the missing tooth portion 45b is not detected when the count-up value of the NE pulse signal detected by the crank angle sensor 46 becomes a pulse value corresponding to the missing tooth detection target position. Only when it continues, the failure of the starter 20 is notified.

  The ECU 100 notifies the failure of the starter 20 by lighting or blinking the eco-run indicator 53. This notification mode may be a notification mode that appeals to hearing using voice, buzzer, or the like. In this embodiment, ECU 100 constitutes a target rotation angle calculation means and a failure determination means.

  Next, a failure detection method for the starter 20 will be described based on the flowcharts of FIGS. The flowcharts shown in FIGS. 8 and 9 are abnormality detection programs for the starter 20 that are stored in the ROM 100c of the ECU 100 and executed by the CPU 100a.

  First, the CPU 100a of the ECU 100 determines whether or not an idling stop condition is satisfied (step S1). In step S1, when the accelerator opening is “0” and the shift position is “neutral position” or “parking position” based on the output signals from the throttle sensor 51 and the shift position sensor 52, the idling stop condition is set. The engine 1 is stopped by determining that is satisfied and stopping the fuel injection control and the ignition control.

  Next, the CPU 100a determines whether or not the engine 1 is stopped (step S2). If it is determined that the engine is stopped, the CPU 100a stores the stop crank position (step S3). Here, when the rotation of the crankshaft 8 is stopped, the crank angle of the crankshaft 8 is stored in increments of 10 ° CA. As shown in FIG. 5, when the crank angle from the protrusion 45a detected by the crank angle sensor 46 to the protrusion 45a is 50 ° CA, “1” is stored as the crank counter value.

  Next, it is determined whether or not the starter 20 has been turned on, that is, whether or not the starter motor 21 has been operated (step S4). That is, at least when the accelerator pedal is operated and a signal is input from the throttle sensor 51 where the accelerator opening is not “0”, the idling stop condition is not satisfied, and the starter 20 is turned “on”.

  If the CPU 100a determines that the starter 20 is "ON", the CPU 100a calculates the missing tooth detection target position using the map of FIG. 10 (step S5). A map for calculating the missing tooth detection target position is stored in the ROM 100c of the ECU 100.

  FIG. 10 is a diagram showing the relationship between the stop position of the crankshaft 8 and the missing tooth detection target position from the stop position until the missing tooth portion 45b is detected, that is, the target rotation angle of the crank angle. In FIG. 10, when the stop position of the crankshaft 8 is in the range of 0 ° to 60 °, the missing tooth detection target position is set to a position of 210 °. For example, if the crank stop position is 10 ° CA, it is predicted that the missing tooth portion 45b is detected when the crank rotor 45 rotates by 210 ° CA from that position.

  When the stop position of the crankshaft 8 is in the range of 70 ° to 420 °, the missing tooth detection target position is set to a position of 570 °. For example, if the crank stop position is 50 ° CA, it is predicted that the missing tooth portion 45b is already detected when the crank rotor 45 rotates by 210 ° CA from the crank stop position.

  As is apparent from FIG. 5, when the crank stop position is, for example, 100 ° CA or 110 ° CA, when the crank rotor 45 rotates by 570 ° CA from the crank stop position, the missing tooth portion 45b is detected twice.

  The pulse signal for detecting the first missing tooth portion 45b is 20 ° CA in the case of 100 ° CA, and 10 ° CA in the case of 110 ° CA. Therefore, the ECU 100 ignores the 30 ° CA pulse signal input from the crank angle sensor 46 for the first time.

  The width of the stop position of the crankshaft 8 with respect to the missing tooth detection target position in this way is that the missing tooth detection target position from the stop position of the crankshaft 8 when the reverse rotation of the crankshaft 8 does not occur. This is to make it possible to reliably detect the missing tooth portion 45b.

  Next, the NE pulse signal is interrupted based on the output signal from the crank angle sensor 46 (step S6), and the NE pulse signal is counted up from the stop crank position stored in the RAM 100b (step S7).

  Next, the cylinder to be ignited is determined based on the stop position of the crankshaft 8 stored in the RAM 100b, and fuel injection is performed (step S8). In FIG. 5, when the crank counter value stored in the RAM 100b is “1”, fuel is injected into the fourth cylinder # 4.

  Further, as apparent from FIG. 5, when the crankshaft 8 is at the stop position corresponding to the crank counter value “1” including 50 ° CA, the fuel injection order of the cylinders after the fourth cylinder # 4 is The second cylinder # 2, the first cylinder # 1, and the third cylinder # 3 are arranged in this order.

  Next, when the crankshaft 8 is rotated by the target rotation angle from the stop position of the crankshaft 8, it is determined whether or not the missing tooth portion 45b is in a position to be detected (step S9). In step S9, it is determined whether or not the NE pulse signal from when the rotation of the crankshaft 8 has stopped reaches a count-up value corresponding to the missing tooth detection target position. In FIG. 10, if the NE pulse signal at the stop position of the crankshaft 8 is 50 ° CA, it is determined whether or not the missing tooth detection target position is 210 °.

  When determining that the count-up value of the NE pulse signal has not reached the missing tooth detection target position, the CPU 100a returns the process to step S5. If the CPU 100a determines that the crank angle is at a position where the missing tooth portion 45b should be detected, whether the 30 ° CA signal has been detected, that is, whether missing tooth detection has already been performed. Is discriminated (step S10).

  In step S10, it is determined that the missing tooth portion 45b is detected when the count-up value of the NE pulse signal detected by the crank angle sensor 46 from the stop position of the crankshaft 8 reaches the missing tooth detection target position. Start control is executed (step S11), and the current process is terminated.

  For example, when the stop position of the crankshaft 8 is 50 ° CA and the determination result in step S10 is “YES”, the NE pulse signal is counted up by 210 ° CA from this stop position. It is determined that the tooth portion 45b has already been detected, it is determined that the starter 20 is normal, and the fourth cylinder # 4 is ignited in step S11. The order of ignition of the cylinders after the fourth cylinder # 4 is the order of fuel injection, which is the order of the second cylinder # 2, the first cylinder # 1, and the third cylinder # 3.

  On the other hand, if the CPU 100a determines in step S10 that missing tooth detection has not been performed, the count-up value of the NE pulse signal detected by the crank angle sensor 46 from the stop position of the crankshaft 8 is detected as missing tooth detection. Although the missing tooth portion 45b is not detected even though the target position has been reached, it is determined that there is a possibility of failure of the starter 20, and it is determined that ignition should be performed first as shown in FIG. The fuel injection and ignition are reset for the cylinders that have been performed (step S21).

  Here, since the starter 20 has the one-way clutch 26 as a reverse rotation prevention mechanism for the crankshaft 8, the rotation transmission from the support shaft 24 to the intermediate gear 27 is allowed and the rotation transmission from the intermediate gear 27 to the support shaft 24 is prevented. It is supposed to be.

  However, when the missing tooth portion 45b is not detected even though the count-up value of the NE pulse signal detected by the crank angle sensor 46 from the stop position of the crankshaft 8 has reached the missing tooth detection target position. Since there is a possibility that the crankshaft 8 is reversely rotated due to some abnormality in the one-way clutch 26 and the like, there is a possibility that an accurate crank angle cannot be detected. Therefore, in step S21, the fuel injection and ignition are reset, and a process for preventing erroneous ignition in which cylinders other than the cylinder to be ignited are executed is executed.

  Next, the NE pulse signal is interrupted based on the output signal from the crank angle sensor 46 (step S22), and it is determined whether or not a 30 ° CA signal is detected, that is, whether or not missing teeth are detected. (Step S23).

  If the CPU 100a determines that missing tooth detection has been performed in step S23, the CPU 100a corrects the crank position based on the missing tooth portion 45b detected by the crank angle sensor 46 (step S24). The cylinder to be ignited is determined based on the crank position, and fuel injection control and ignition control are executed (step S25).

  Next, after counting up the abnormality detection counter provided in the RAM 100b (step S26), the CPU 100a determines whether the count-up value of the abnormality detection counter is a predetermined value, for example, “5” or more. Is discriminated (step S27).

  If the CPU 100a determines that the count-up value of the abnormality detection counter is less than “5”, the CPU 100a ends the current process and determines that the count-up value of the abnormality detection counter is “5” or more. In this case, the number of times that the missing tooth portion 45b is not detected even though the count-up value of the NE pulse signal detected by the crank angle sensor 46 has reached a pulse value corresponding to the missing tooth detection target position continues. Therefore, it is determined that a failure of the starter 20 has occurred, and the failure of the starter 20 is notified by lighting or blinking the eco-run indicator 53 (step S28). Next, the value of the abnormality detection counter is reset (step S29), and the current process is terminated.

  As described above, in the present embodiment, the target rotation angle of the crank angle from the crank angle stored when the crankshaft 8 is stopped to the reference position is calculated, and after the start of the engine 1 is started by the starter 20, Whether or not the crankshaft 8 is reversely driven by the one-way clutch 26 or the like by determining whether or not the missing tooth portion 45b is detected when the crankshaft 8 is rotated by the target rotation angle since the rotation of the shaft 8 is stopped. It is possible to determine whether there is a failure in the starting device 20 or not.

  Further, in the present embodiment, after the start of the engine 1 by the starter 20, the missing tooth portion 45b is detected when the crankshaft 8 rotates by the target rotation angle from the time when the rotation of the crankshaft 8 stops. In this case, it is determined that the starter 20 is normal and the cylinder to be ignited is determined and the fuel injection control and the ignition control are performed. Therefore, the startability of the engine 1 can be improved.

  In the present embodiment, after the start of the engine 1 is started by the starter 20 and the start of the engine 1 is started by the starter 20, the CPU 100a starts the crankshaft 8 from the time when the crankshaft 8 stops rotating. When the missing tooth portion 45b is not detected when the engine is rotated by the target rotation angle, it is highly possible that the crankshaft 8 has been reversely rotated due to a failure of the starter 20, so the cylinder determined to be the first cylinder Since the fuel injection control and the ignition control are stopped with respect to the engine 1, it is possible to prevent erroneous ignition after the start of the operation of the starter 20, and the load on the engine 1 increases. Can be prevented.

  Further, in the present embodiment, after the start of the engine 1 by the starter 20 is started, the CPU 100a performs the crank angle sensor 46 when the crankshaft 8 rotates by the target rotation angle from the stop of the rotation of the crankshaft 8. When the missing tooth portion 45b is not detected by the above, it is highly possible that the starter 20 has failed and the crankshaft 8 is reversely rotated. Therefore, ignition is performed based on the missing tooth portion 45b detected by the crank angle sensor 46. Since the fuel injection control and the ignition control are executed again by determining the cylinder to be ignited, it is possible to accurately determine the cylinder to be ignited even when the starter 20 is out of order, and to ensure that misignition occurs. Can be prevented.

  Further, in this embodiment, after the start of the engine 1 by the starter 20, the crank angle sensor 46 lacks teeth when the crankshaft 8 rotates by the target rotation angle from the time when the rotation of the crankshaft 8 stops. When the number of times the part 45b is not detected continues five times, the eco-run indicator 53 is notified that a failure of the starter 20 has occurred.

  That is, after the start of the engine 1 is started by the starter 20, the crank angle sensor 46 causes the missing tooth portion 45b even though the crankshaft 8 has been rotated by the target rotation angle since the crankshaft 8 stopped rotating. When the situation in which the engine is not detected repeatedly occurs, it is determined that the starter 20 has definitely failed, and the eco-run indicator 53 notifies the driver that the starter 20 has failed. And prompt prompt action.

  Further, after the start of the engine 1 by the starter 20, the crank angle sensor 46 causes the missing tooth portion 45 b even though the crankshaft 8 has been rotated by the target rotation angle since the crankshaft 8 stopped rotating. If the situation in which the engine is not detected is continuously generated less than 5 times, it is determined that the crank angle detection signal is affected by noise or the like, and the failure notification is not performed, so the starter 20 is continued. Can be used.

  The one-way clutch of the present embodiment uses a sprag, but it may be a roller type having a roller as a biting member and a spring for biasing the roller. Further, an outer ring cam type in which a flat or curved cam surface is provided on the outer ring, or an inner ring type in which a cam surface is provided on the inner ring may be used.

  In addition, the embodiment disclosed this time is illustrative in all respects and is not limited to this embodiment. The scope of the present invention is shown not by the above description of the embodiments but by the scope of the claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of the claims.

  As described above, the start control device for an internal combustion engine according to the present invention has an effect that it can accurately determine whether or not there is a failure in the starter, and determines whether or not there is a failure in the starter that starts the internal combustion engine. This is useful as a start control device for an internal combustion engine.

1 is a diagram showing an embodiment of a start control device for an internal combustion engine according to the present invention, and is a cross-sectional view of a main part of the internal combustion engine. 1 is a diagram showing an embodiment of a start control device for an internal combustion engine according to the present invention, and is a partial sectional view showing a main part of a start device provided in the engine. It is a figure which shows one Embodiment of the starting control apparatus of the internal combustion engine which concerns on this invention, and is an enlarged view of the part shown by III of FIG. It is a figure which shows one Embodiment of the starting control apparatus of the internal combustion engine which concerns on this invention, and is a figure which shows the operating state of a one-way clutch. It is a figure which shows one Embodiment of the starting control apparatus of the internal combustion engine which concerns on this invention, and is a timing chart which shows operation | movement of an internal combustion engine. 1 is a diagram showing an embodiment of a start control device for an internal combustion engine according to the present invention, and is a diagram showing a crank rotor. FIG. It is a figure which shows one Embodiment of the starting control apparatus of the internal combustion engine which concerns on this invention, and is a figure which shows a cam rotor. It is a figure which shows one Embodiment of the starting control apparatus of the internal combustion engine which concerns on this invention, and is an abnormality detection program of a starting apparatus. FIG. 9 is an abnormality detection program for the starting device subsequent to FIG. 8. FIG. It is a figure which shows one Embodiment of the starting control apparatus of the internal combustion engine which concerns on this invention, and is a figure which shows the relationship between a missing tooth detection target position and the stop position of a crankshaft.

Explanation of symbols

1 engine (internal combustion engine)
2 cylinders 8 crankshaft 20 starter (starting means)
21 Starter motor (starting motor)
26 One-way clutch (clutch)
46 Crank angle sensor (crank angle detection means, reference position detection means, target reference position calculation means, failure determination means)
100 ECU (crank angle detection means, reference position detection means, internal combustion engine control means, target rotation angle calculation means, failure determination means)
100b RAM (crank angle storage means)

Claims (4)

A starter motor, and a one-way clutch that transmits the power of the starter motor to the crankshaft of the internal combustion engine and prevents the power from the crankshaft from being transmitted to the starter motor. Starting means for starting; and
Crank angle detecting means for detecting a crank angle of the crankshaft;
Reference position detection means for detecting a reference position set to the crank angle;
Crank angle storage means for storing a crank angle when rotation of the crankshaft is stopped;
Target rotation angle calculation means for calculating a target rotation angle of a crank angle determined based on the crank angle stored in the crank angle storage means;
After the start of the internal combustion engine by the starter, the reference position is not detected by the reference position detector when the crankshaft rotates by the target rotation angle from when the crankshaft stops rotating. A start control device for an internal combustion engine , comprising: failure determination means for determining that the start means has failed when it is determined that the start means has failed. When the stop condition of the internal combustion engine is satisfied, the fuel injection control and the ignition control are stopped, and when the start of the internal combustion engine is started by the starter, the internal combustion engine executes the fuel injection control and the ignition control for the cylinder. With control means,
When the failure determination means determines that the reference position is detected by the reference position detection means when the crankshaft is rotated by the target rotation angle from the time when the rotation of the crankshaft is stopped, The internal combustion engine control means determines the cylinder to be ignited and executes fuel injection control and ignition control on the cylinder to be ignited;
When the failure determination means determines that the reference position is not detected by the reference position detection means when the crankshaft rotates by the target rotation angle from the time when the rotation of the crankshaft is stopped, the internal combustion engine 2. The start control device for an internal combustion engine according to claim 1, wherein the engine control means stops performing the fuel injection control and the ignition control for the cylinder that is first determined to be ignited.   When the failure determination means determines that the reference position is not detected by the reference position detection means when the crankshaft rotates by the target rotation angle from the time when the rotation of the crankshaft is stopped, the internal combustion engine 3. The internal combustion engine according to claim 2, wherein the engine control means determines again a cylinder to be ignited based on the reference position detected by the reference position detection means, and executes fuel injection control and ignition control. Start control device.   When the crankshaft is rotated by the target rotation angle from the time when the crankshaft stops rotating, the failure determination means continuously counts a predetermined number of times that the reference position is not detected by the reference position detection means. The start control device for an internal combustion engine according to any one of claims 1 to 3, wherein when the determination is made, a failure of the start means is notified.

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