JP4331124B2 - Internal combustion engine starter and method - Google Patents

Description

  The present invention relates to a starting method and a starting device for an internal combustion engine, and more particularly, to a starting method and a starting device for an internal combustion engine for a vehicle that performs idle stop.

  In recent years, there has been an increase in the number of vehicles that perform idle stop for the purpose of reducing the fuel consumption and exhaust of an internal combustion engine. Idle stop automatically stops the internal combustion engine when the internal combustion engine is in an idle state while the vehicle is stopped, and automatically restarts the internal combustion engine when starting, and various techniques have been proposed for this purpose. .

  If it takes a long time to restart the internal combustion engine in idling stop, the start operation of the vehicle is delayed with respect to the driver's intention to start, and drivability deteriorates. For this reason, it is important to restart the internal combustion engine quickly and smoothly when performing idle stop.

  In addition, an idle stop system that performs cranking and restarting by applying a rotational torque to the crankshaft from the outside using a starter motor requires a large amount of electric power during cranking and places a burden on the battery. It will greatly accelerate battery deterioration.

  On the other hand, when the engine is stopped, fuel injection (in-cylinder injection) is performed on the cylinder in the expansion stroke, ignition of the corresponding cylinder is performed, and the internal combustion engine itself generates rotational torque due to combustion. The internal combustion engine is restarted without using it, and the success or failure of the start is determined based on the engine speed after the start of combustion. A starter that supplements energy has been proposed (for example, Patent Document 1).

  However, this starting device is started by external energy such as a starter motor after determining a starting failure, and the engine starting at the time of combustion failure is insufficient.

  In order to solve this, by setting energy required for starting the internal combustion engine as target energy, and supplying energy controlled according to the target energy from the predetermined starting energy supply means to the internal combustion engine, There has been proposed a starting device that estimates a starting failure and supplies optimum energy at the time of starting (for example, Patent Document 2).

  This starting device uses, as starting energy supply means, first energy supplying means for obtaining rotational torque (energy) by combustion of fuel in a cylinder by in-cylinder injection, and second energy supplying means by a starter motor, The energy given to the internal combustion engine by the first energy supply means is estimated, and the shortage relative to the target energy is compensated by the second energy supply means.

  For this reason, in this starting device, in order to supply energy by the second energy supply means, it is necessary to accurately calculate in advance the energy obtained by combustion. However, it is difficult to accurately calculate the combustion energy, and in order to calculate more accurately, it is necessary to add an expensive sensor such as an in-cylinder pressure sensor. If the combustion energy cannot be accurately calculated, the energy supply amount by the second energy supply means cannot be accurately calculated. Therefore, the start failure when the energy supply amount by the second energy supply means is insufficient, the second Since excessive energy consumption occurs when the amount of energy supplied by the energy supply means is excessive, there is a case where optimum energy supply for starting the internal combustion engine and starting performance cannot be compatible.

Japanese Patent Laid-Open No. 2002-4985 JP 2004-108340 A

  The problem to be solved by the present invention is to start the internal combustion engine by using the energy by the combustion energy obtained by injecting and igniting the fuel into the cylinder in the expansion stroke of the internal combustion engine whose rotation is stopped. An object of the present invention is to minimize the amount of energy supplied by energy supply means other than the combustion energy without accurately calculating the combustion energy, and to realize a stable start without causing a start failure due to a combustion failure.

  In the internal combustion engine starter according to the present invention, fuel is injected into a cylinder in an expansion stroke in a state where the internal combustion engine is stopped to ignite, and combustion is sequentially generated from the cylinder in the expansion stroke. First energy supply means for starting the internal combustion engine using the energy of the second energy, second energy supply means for starting the internal combustion engine by applying rotational torque to the crankshaft of the internal combustion engine from the outside, and the first And a third energy supply means for starting the internal combustion engine by applying a rotational torque from the outside to the crankshaft of the internal combustion engine in a system different from the second energy supply means.

  In the internal combustion engine starter according to the present invention, fuel is injected into a cylinder in an expansion stroke in a state where the internal combustion engine is stopped to ignite, and combustion is sequentially generated from the cylinder in the expansion stroke. First energy supply means for starting the internal combustion engine using the energy of the second energy, second energy supply means for starting the internal combustion engine by applying rotational torque to the crankshaft of the internal combustion engine from the outside, and the first A third energy supply means for starting the internal combustion engine by applying rotational torque from the outside to the crankshaft of the internal combustion engine in a system different from the energy supply means, and a motion state for determining the motion state of the internal combustion engine When the internal combustion engine is started, the determination means and energy from all of the first energy supply means, the second energy supply means, and the third energy supply means are stored in the internal energy. And supplying the engine to start the internal combustion engine, and the internal combustion engine by the second energy supply means and the third energy supply means based on the determination result by the motion state determination means after the start of motion of the internal combustion engine Energy supply control means for stopping the supply of energy to.

Starting system for an internal combustion engine according to the present invention, preferably, the second energy supply unit is configured by a starter including a starter motor, and the gear selection gear mechanism, the third energy supply means, belt It is a starter generator that is always connected by transmission.

  In the internal combustion engine starter according to the present invention, preferably, the motion state determination means is configured such that the rotational speed of the internal combustion engine at the time of ignition of the first energy supply means and the crank angle of the internal combustion engine from the time of ignition. When the rotational state of the internal combustion engine is determined to be maintained from the difference in rotational speed when the predetermined rotational angle changes, the energy supply control means determines that the second state is determined to be maintained by the motion state determination means. The energy supply to the internal combustion engine by the energy supply means and the third energy supply means is stopped.

  In the internal combustion engine starter according to the present invention, preferably, the motion state determination means is the internal combustion engine when the first energy supply means ignites a cylinder in a compression stroke when the internal combustion engine is stopped. It is determined that the rotational state of the internal combustion engine continues from the difference between the rotational speed of the internal combustion engine and the rotational speed at the time when the crank angle of the internal combustion engine changes by a predetermined rotational angle from the ignition time.

  In the internal combustion engine start method according to the present invention, fuel is injected into a cylinder in an expansion stroke while the internal combustion engine is stopped, and ignition is performed, and combustion is sequentially generated from the cylinder in the expansion stroke. First energy supply means for starting the internal combustion engine using the energy of the second energy, second energy supply means for starting the internal combustion engine by applying a rotational torque to the crankshaft of the internal combustion engine from the outside, And a third energy supply means for starting the internal combustion engine by applying a rotational torque from the outside to the crankshaft of the internal combustion engine in a system different from that of the energy supply means. Energy is supplied from all of the energy supply means, the second energy supply means, and the third energy supply means to the internal combustion engine to start the internal combustion engine; After the movement of the combustion engine starts, the state of movement of the internal combustion engine is determined, and the supply of energy to the internal combustion engine by the second energy supply unit and the third energy supply unit is stopped based on the determination result. .

The method of starting an internal combustion engine according to the present invention, preferably, the second energy supply unit is configured by a starter including a starter motor, and the gear selection gear mechanism, the third energy supply means, belt It is a starter generator that is always connected by transmission.

  In the internal combustion engine start method according to the present invention, preferably, the determination of the motion state of the internal combustion engine is performed by determining the rotational speed of the internal combustion engine at the time of ignition of the first energy supply means, and the internal combustion engine from the time of ignition. When it is determined that the rotation state of the internal combustion engine continues from the difference in rotation speed when the crank angle changes by a predetermined rotation angle, and when it is determined that the rotation continues, the second energy supply means and the third energy supply The energy supply to the internal combustion engine by the means is stopped.

  In the internal combustion engine start method according to the present invention, preferably, the determination of the motion state of the internal combustion engine is performed when the first energy supply means ignites a cylinder that is in a compression stroke when the internal combustion engine is stopped. It is determined that the state of motion of the internal combustion engine continues from the difference between the rotational speed of the internal combustion engine and the rotational speed at the time when the crank angle of the internal combustion engine changes by a predetermined rotational angle from the ignition time.

  According to the present invention, the crank as the auxiliary energy supply means for compensating for the shortage of energy supply to the internal combustion engine by the first energy supply means for starting the internal combustion engine using the energy of combustion of the fuel by in-cylinder injection. The second energy supplying means for starting the internal combustion engine by applying rotational torque to the shaft from the outside, and the second energy supplying means for starting the internal combustion engine by applying rotational torque to the crankshaft from the outside in a different manner. Since the two energy supply means of the third energy supply means are used, the shortage of energy supply to the internal combustion engine at the time of starting can be shared by the second energy supply means and the third energy supply means. As a result, the supply current supplied to each of the second energy supply means and the third energy supply means can be reduced, and the respective deterioration of the second energy supply means and the third energy supply means is suppressed accordingly. Is done. In addition, fail safe is achieved when either one of the second energy supply unit and the third energy supply unit fails.

  Further, according to the present invention, it is not necessary to calculate the energy supplied at the time of starting by each energy supply means, and it is possible to stop a part of the energy supply by determining the motion state generated by the energy supplied at the time of starting. Therefore, it is possible to realize a stable start without causing a start failure while minimizing the supply amount of the second or third energy without accurately calculating the supplied energy. The noise can be reduced. Furthermore, since it is not necessary to add a sensor for performing energy estimation with high accuracy or use a high-functional energy supply means, a starting system can be constructed at a low cost.

  The determination of the state of motion of the internal combustion engine is based on the difference between the rotational speed of the internal combustion engine at the time of ignition and the rotational speed at the time when the crank angle of the internal combustion engine changes by a predetermined rotational angle from the time of ignition, Simple determination without adding a special sensor by judging from passing through a predetermined rotation position of the crankshaft where the load torque around the crankshaft is maximized by the compression pressure generated in the cylinder in the compression stroke Can be done.

  An embodiment of an internal combustion engine applied to a start control device according to the present invention will be described with reference to the drawings.

  In FIG. 1, an internal combustion engine 1 is configured as a four-cycle engine mounted on, for example, an automobile, and includes a plurality of cylinders (cylinders) 2. Although only a single cylinder 2 is shown in FIG. 1, the other cylinders 2 have the same configuration. In the following description, the internal combustion engine 1 may be referred to as the engine 1.

  The number of cylinders 2 in the engine 1 is 3, 4, 6, 8, etc., which are called a three-cylinder engine, a four-cylinder engine, a six-cylinder engine, and an eight-cylinder engine, respectively.

  The engine 1 directly injects fuel (in-cylinder injection) from the fuel injection valve 4 into the combustion chamber 5 in the cylinder 2, and ignites an air-fuel mixture of the injected fuel and air in the combustion chamber 5 by the spark plug 6. It is configured as an in-cylinder injection internal combustion engine that performs (ignition). Gasoline is suitably used as the fuel injected from the fuel injection valve 4, but other fuels may be used.

  The engine 1 is provided with an intake valve 9 and an exhaust valve 10 for opening and closing between the combustion chamber 5 and the intake passage 7 and between the combustion chamber 5 and the exhaust passage 8, respectively, and opening and closing the intake valves 9 and the exhaust valves 10. Cams 11 and 12, a throttle valve 13 that adjusts the amount of intake air from the intake passage 7, a connecting rod 15 that transmits the reciprocating motion of the piston 3 to the crankshaft 14 as a rotational motion, and a crank arm 16.

  In addition, the opening / closing timing and the lift amount of the intake valve 9 and the exhaust valve 10 may be freely changed. The valve timing / lift control device 20 changes the opening / closing timing and the lift amount of the intake valve 9 and the exhaust valve 10.

  As an energy supply means for supplying energy (rotational torque) for starting the engine 1 to the engine 1, means for generating combustion in the combustion chamber 5 and supplying energy required at the start (first energy supply) Means). The first energy supply means injects fuel into the cylinder in the expansion stroke while the engine 1 is stopped, performs ignition, and sequentially generates combustion from the cylinder in the expansion stroke. Is used to start the engine 1 and is realized by control performed on each cylinder of the engine 1 from a state in which the control unit 19 is stopped. The energy supply method by the first energy supply means will be described later in detail.

  The engine 1 is provided with a starter motor 17 as second energy supply means (starter). The starter motor 17 is an electric motor that rotates the crankshaft 14 via a gear mechanism 18, and selectively engages with the gear mechanism 18 to apply rotational torque to the crankshaft 14 from the outside to start the engine 1. It is.

  The starter motor 17 can change the energy applied to the engine 1 by controlling the supplied current or voltage, or, as is generally used, the current / voltage control is not performed and the energization is turned on. -Some control only when off.

  Further, the third energy supply means (starter / generator) is connected to the engine 1 by a belt 21, for example, around the crankshaft 14 of the engine 1 like a belt-driven ISG (Integrated Starter Generator). An always-connected electric motor 22 is provided. This electric motor 22 has a power generation function and a motor function to form a starter / generator, and is replaced with a conventional alternator installation location to generate an alternator function that generates power using the power of the engine 1. In addition to this, it is possible to provide a starter function for rotationally driving the crankshaft 14 of the engine 1, which is excellent in mountability.

  The control unit 19 is configured as a computer type including peripheral devices such as a microprocessor, a RAM, and a ROM, and performs various processes necessary for controlling the operating state of the engine 1 in accordance with a program recorded in the ROM.

  For example, an air-fuel ratio sensor (not shown) is installed in the exhaust passage 8 and the fuel injection amount of the fuel injection valve 4 is controlled so that the air-fuel ratio measured by the air-fuel ratio sensor becomes a predetermined air-fuel ratio.

  Various sensors other than the above-described sensors are provided as sensors to be referred to by the control unit 19, but the sensors related to the present invention include a crank angle sensor 24 that outputs a signal corresponding to the crank angle of the crankshaft 14, There is a cam angle sensor 25 that outputs a signal according to the cam angle of the cam 11 on the intake side.

  Next, an embodiment of the present invention by the control unit 19 will be described with reference to FIG. The control unit 19 is a device necessary for starting up, stopping, and operating the engine 1 and processing for fetching a signal from a sensor that detects a state necessary for starting, stopping, and operating the engine 1 into the control unit 19. Input / output means 90 for performing output processing for driving and controlling a certain throttle valve 13, valve timing / lift control device 20, fuel injection valve 4 and the like, and normal control means for normally starting and operating the engine 1 In addition, start control means 91 and stop control means 92 are provided.

  The start control means 91 is a control means for starting the engine 1, and the stop control means 92 is a control means for stopping the engine 1.

  In the present invention, the start control means 91 includes a motion state determination means 911 for detecting and determining the motion state of the engine 1 and the plurality of energy supply means (first energy supply means) described above for supplying energy to the engine 1. And an energy supply control means 912 for controlling the second energy supply means and the third energy supply means).

  The motion state determination unit 911 is configured to detect the rotational speed of the engine 1 at the time of ignition of the first energy supply unit, in particular, the time of ignition of the cylinder in the compression stroke when the engine is stopped, and the crank angle of the engine 1 from the ignition point. It is determined that the rotational state of the engine 1 is maintained from the difference in rotational speed at the time when the predetermined rotational angle changes.

  The motion state determination means 911 has passed a predetermined rotational position of the crankshaft where the load torque around the crankshaft is maximized by the compression pressure generated in the cylinder that was in the compression stroke when the engine 1 was stopped. From this, it may be determined that the engine rotation state is maintained.

  The energy supply control means 912 basically starts the engine 1 by supplying energy to both the first energy supply means and the second energy supply means (starter motor 17) when starting the engine 1. After the start of the engine 1, when it is determined that the motion state determination unit 911 continues to rotate based on the determination result by the motion state determination unit 911, the energy is supplied to the engine 1 by the second energy supply unit. Control to stop.

  Details of the start control means 91 will be described with reference to FIG. The energy supply control means 912 in the start control means 91 includes a supply / stop control means 9121, a combustion control means 9122 that performs the first energy supply control, and a starter control means 9123 that performs the second energy supply control. A starter generator control unit 9124 for performing supply control is provided.

  The combustion control means 9122 includes a fuel injection control unit 91221 for setting the amount of fuel to be injected by the fuel injection valve 4 and an injection timing, an ignition control unit 91222 for setting the timing for ignition by the spark plug 6, and valve timing / lift The control device 20 includes an intake / exhaust valve control unit 91223 for setting the opening / closing timing and the valve opening amount of the intake valve 9 and the exhaust valve 10, and a throttle control unit 91224 for setting the opening of the throttle valve 13. Energy is supplied to the engine 1 by realizing optimal combustion control.

  When the engine 1 is started, the supply / stop control unit 9121 controls energy supply and stop by a plurality of energy supply units. In particular, based on the determination result by the movement state determination unit 911, that is, according to the movement state of the engine 1, the energy supply of the plurality of energy supply units is appropriately performed or stopped. In this manner, by performing energy supply or stop according to the motion state of the engine 1, stable start can be realized without causing a start failure and without excessive energy supply.

Next, a control flow in the start control of the present invention will be described.
Before explaining the details of the control flow of the start control, a schematic flow of the stop control performed before the start and the subsequent start control will be described with reference to FIG.

  The stop control flow and the start control flow are executed by the stop control means 92 and the start control means 91 of the control unit 19.

  Further, the control unit 19 determines whether the engine 1 is stopped or started in a processing flow different from this processing, and the stop control flow and the start control flow are executed based on the stop request and the start request. .

  Here, the stop condition is determined, for example, when the engine 1 is in a warm-up state, a brake operation state, and an idling state where the accelerator is not stepped on.

  The starting condition is determined when there is an operation related to starting of the vehicle from the idling state, for example, a brake release, an accelerator pedal depression operation, a shift operation, or the like.

  As described above, the processing flow of the stop control and the start control shown in FIG. 4 realizes an idling stop that stops the engine 1 and restarts the engine 1 before starting the vehicle when the vehicle is stopped.

  In FIG. 4, in the engine operating state (step S0), the control unit 19 first determines whether or not there is an engine automatic stop request (step S1-1). If there is no request for automatic stop, normal control of the engine 1 is continued (step S2), and thereafter, it is repeatedly determined whether there is a request for automatic engine stop.

If there is a request for automatic stop, engine stop control (step S1-2) is performed.
When the engine stop control (step S1-2) is completed and the engine 1 is stopped, the crank angle and the cam angle are detected from the crank angle sensor 25 and the cam angle sensor 26, and the cylinder (cylinder) in the expansion stroke is detected from these detection results. A cylinder discrimination process for discriminating 2) is performed (step S1-3).

  Next, the piston stop position of the cylinder in the expansion stroke is calculated from the crank angle (step S1-4). At this time, piston stop positions in cylinders other than the cylinders in the expansion stroke are also uniquely determined.

  Next, the air amount of the cylinders in the expansion stroke and the air amount of the cylinders in the compression stroke are calculated from the piston stop positions of those cylinders (steps S1-5 and S1-6). The piston stop positions of the cylinder in the expansion stroke and the cylinder in the compression stroke are respectively calculated, and the diameter of the cylinder and the top surface shape of the piston 3 are known in advance from the design values. And the volume of the combustion chamber 5 of the cylinder in the compression stroke can be determined.

  Here, the pressure (in-cylinder pressure) in each combustion chamber 5 of the engine 1 is assumed to return to the atmospheric pressure immediately after the engine is stopped, and is expanded by performing temperature correction estimated from the water temperature information of the engine 1 and the like. The amount of air in the cylinder in the stroke and in the cylinder in the compression stroke can be calculated.

  Once the amount of air in the combustion chamber 5 of the cylinder in the expansion stroke and the compression stroke is calculated, the corresponding fuel injection amount is then calculated (step S1-7, step S1-8). This fuel injection amount can be set, for example, so that the air-fuel ratio of the air amount and the fuel amount becomes a predetermined value. The air-fuel ratio at this time is preferably determined to a value that optimizes combustion.

  Also, the amount of fuel to the cylinder in the intake stroke is calculated simultaneously. Step S1-9). Since the cylinder in the intake stroke operates from the intake stroke after the start, the amount of fuel at the normal start may be set assuming that the air is sufficiently sucked into the cylinder.

  As described above, it is possible to calculate in advance the amount of fuel necessary to start the engine 1. The calculation of the fuel necessary for starting is preferably performed by the start control means 91 of the control unit 91.

  Further, immediately after the engine 1 is stopped, the fuel amount may be obtained by the above process, or after the start request is issued, the fuel amount supplied to each cylinder at the start is calculated by the same process. Good.

  Next, in the engine halt state (step S1-10), it waits for a restart request (step S1-11). Here, it is determined whether or not there is a request for starting the engine 1 (step S1-11). If there is a start request, start control of the engine 1 is started (step S3). On the other hand, when there is no start request, the engine 1 remains in a paused state and waits for the start request.

  Next, a processing flow of start control when there is an engine automatic start request will be described with reference to FIG.

  In the state where the engine 1 is stopped (step S1-10), it is determined whether or not there is an engine automatic start request (step S1-11). A first energy supply control for supplying energy to the engine 1 (step S3-1), a second energy supply control for supplying energy to the engine 1 by the second energy supply means (step S3-2), 3rd energy supply control (step S3-2) which supplies energy to the engine 1 by 3 energy supply means is performed.

  The first energy supply control (step S3-1) and the second energy supply control (step S3-2) are performed as independent processing flows, respectively. Regarding the timing of starting the energy supply to the engine 1, At the same time, cooperative control such as starting and starting in order may be performed.

  For example, in the first energy supply control (step S3-1), fuel is injected into each cylinder of the engine 1, combustion is generated in the cylinder by ignition, energy is supplied to the engine 1, and second energy supply control is performed. In (step S3-2), energy is supplied to the engine 1 from the outside by applying rotational torque to the crankshaft 14 of the engine 1 by the starter motor 17, and in the third energy supply control (step S3-3), When energy is supplied to the engine 1 from the outside by applying rotational torque to the crankshaft 14 of the engine 1 by the electric motor 22, first energy supply control (step S3-1) is started first, and then The second energy supply control (step S3-2) and the third energy supply control (step S3-2) after a predetermined time has elapsed (with a certain time delay). -Up S3-2) in order to start. Alternatively, all of the first energy supply control (step S3-1), the second energy supply control (step S3-2), and the third energy supply control (step S3-3) may be started simultaneously.

  As described above, when there is a start request, supply of energy to the engine 1 is started by a plurality of energy supply means. When the first energy supply control (step S3-1), the second energy supply control (step S3-2), and the third energy supply control (step S3-3) are performed, the engine 1 moves. Start.

  In order to quantitatively evaluate the motion state, the engine state is calculated (step S3-4). As a method of calculating the state of the engine 1 quantitatively, for example, there are a method of evaluating from the energy of the engine 1 from the rotational speed and inertia of the engine 1 and a method of evaluating from the amount of change in the rotational speed of the engine 1 and rotational acceleration. Thus, the sustainability of the rotation of the engine 1 can be evaluated by evaluating the motion state of the engine 1.

  Once the engine state is calculated (step S3-4), it is next determined from the calculated state of the engine 1 whether energy can be supplied by the second energy supply means, that is, the starter motor 17 (step S3-5). . Here, it is determined whether or not the motion of the engine 1 continues even if there is no energy supply by the second energy supply means and the third energy supply means.

  If it is determined that the second and third energy supply is necessary, the energy supply by the second and third energy supply means is continued, and thereafter, whether or not the energy supply can be repeatedly performed is determined. When it is determined that the second and third energy supplies are unnecessary, the second energy supply means stops the second energy supply (step S3-6), and the third energy supply means stops the third energy supply. (Step S3-7) is performed.

  Depending on the start request, the case where energy is supplied to the engine 1 by three energy supply means and the case where energy is supplied to the engine 1 by two energy supply means can be used properly. FIG. 6 shows an example in which energy is supplied to the engine 1 at the start using two energy supply means. The start request may differ depending on the situation, such as when an early start is required or when it is necessary to avoid instantaneous energy consumption. The energy supplied at the time of starting can be selected corresponding to the different demands in such a starting request.

  Next, details of the processing flow of the first energy supply control (step S3-1) according to the embodiment of the present invention will be described with reference to FIG. In FIG. 6, reference numerals # 1 to # 4 indicate cylinder numbers of the engine 1.

  In the first energy supply control (step S3-1), when there is an automatic start request for the engine 1, the first energy supply control is started (step S3-1-1). If the amount of fuel supplied to the cylinder of the engine 1 is not calculated before the engine 1 is requested to start, at this point, as already described, the cylinder in the expansion stroke and the combustion chamber 5 of the cylinder in the compression stroke Is calculated, and the fuel injection amount corresponding to this is calculated.

  Also, the amount of fuel to the cylinder in the intake stroke is calculated at the same time. As described above, since the cylinder in the intake stroke operates from the intake stroke after the start, the amount of fuel at the normal start may be set assuming that the air is sufficiently sucked into the cylinder.

  Next, when the first energy supply control is started, fuel is injected into the cylinder (# 1) in the expansion stroke in the initial state (stop state) (step S3-1-2). Next, fuel is injected into the cylinder (# 2) in the intake stroke in the same initial state (stop state) (step S3-1-3). Further, fuel is injected into the cylinder (# 3) in the compression stroke in the same initial state (stop state) (step S3-1-4).

  In the initial state, fuel injection into the cylinder in the expansion stroke (step S3-1-2), fuel injection into the cylinder (# 2) in the intake stroke (step S3-1-3), and the compression stroke The fuel injection (step S3-1-4) into the cylinder (# 3) in the cylinder may be performed simultaneously.

  Next, after performing fuel injection to the cylinder (# 1) in the expansion stroke, it waits for a predetermined time, waits for the fuel to evaporate, and determines whether or not the time for evaporating the fuel has passed (step S3-1). -5). The vaporization time requires about 100 msec.

  When a preset vaporization time has elapsed, the mixture of fuel and air is ignited by the spark plug 6 of the cylinder (# 1) in the expansion stroke in the initial state (step S3-1-6). When the air-fuel mixture in the cylinder (# 1) in the expansion stroke burns, energy is generated by combustion in this cylinder, the piston 3 is pushed down, and the crankshaft 14 starts rotating. On the other hand, when the crankshaft 14 rotates, the piston 3 of the cylinder (# 3) in the compression stroke in the initial state is pushed up and reaches the top dead center (TDC).

  At this time, since the air-fuel mixture in the cylinder (# 3) in the compression stroke is compressed, a rotational load is generated to prevent the compression. However, since the kinetic energy for directly rotating the crankshaft 14 is also applied by the second energy supply means, that is, the starter motor 17, the crankshaft 14 continues to rotate.

  Next, it is determined whether or not the piston 3 of the cylinder (# 3) in the compression stroke in the initial state has reached the top dead center (TDC) (step S3-1-7), and the cylinder (# in the compression stroke) The compressed air-fuel mixture of 3) is ignited (step S3-1-8). The ignition timing may be ignited at a predetermined angle before TDC, in addition to determining whether the piston 3 of the cylinder (# 3) has reached top dead center (TDC).

  When the cylinder (# 3) in the compression stroke is ignited in the initial state, combustion occurs in this cylinder, and further energy is supplied to the engine 1, and the crankshaft 14 of the engine 1 rotates.

  Next, it is determined whether or not the cylinder (# 4) that was in the exhaust stroke in the initial state has transitioned to the intake stroke (step S3-1-9). Fuel is injected into the cylinder (# 4) that was present (step S3-1-10). Although the fuel is injected in the intake stroke here, the fuel may be injected in the subsequent compression stroke.

  When the crankshaft 14 further rotates, the cylinder (# 2) that was in the intake stroke in the initial state transitions from the intake stroke to the compression stroke, and it is determined whether or not the piston 3 has reached TDC in the compression stroke (step). S3-1-11). If it is determined that the TDC has been reached, the air-fuel mixture in the cylinder (# 2) is ignited (step S3-1-12).

  As described above, the fuel is supplied to the engine 1 by sequentially injecting and igniting each cylinder. When the crankshaft 14 rotates, the engine 1 shifts to normal control, and the optimal timing, optimal amount of fuel injection, and ignition at optimal timing are performed while performing cylinder discrimination (step S3-1-13). .

  Next, a specific example of engine state calculation (step S3-4) and energy supply availability determination (step S3-5) according to an embodiment of the present invention will be described with reference to FIG.

  The engine state calculation (step S3-4) is performed after starting control is started. First, it is determined whether to calculate the first engine state (step S3-4-1). This determines whether to calculate the state of the engine 1. If it is determined that the calculation is to be executed, the number of revolutions when the engine 1 is ignited is calculated (step S3-4-2). On the other hand, if it is determined not to calculate, the determination is continued again.

  Once the number of revolutions at the time of ignition of the engine 1 is calculated, it is next determined whether or not to calculate the second engine state (step S3-4-3). This determines whether or not the rotation angle of the crankshaft 14 has become a predetermined angle in order to calculate the engine state when the crankshaft 14 has moved a predetermined rotation angle after ignition control. Here, the determination is based on the rotation angle of the crankshaft 14, but it may be determined based on whether or not a predetermined time has elapsed after ignition.

  Here, if it is determined that the rotational angle of the crankshaft 14 has changed by a predetermined rotational angle, the rotational speed of the engine 1 at that time is calculated (step S3-4-4).

  Next, the amount of change (difference) in the rotational speed before and after ignition is calculated from the rotational speed of the engine 1 in the first engine state and the rotational speed of the engine 1 after a predetermined rotational angle rotation (step S3-4-5).

  The amount of change in the rotational speed before and after ignition is the result of calculating the operating state of the engine 1. When the amount of change in the rotation speed is large, it means that the engine 1 receives sufficient energy and the rotation continues.

  On the other hand, when the amount of change in the rotational speed is small, there is a high possibility that sufficient energy is not supplied to the engine 1 and the rotation of the engine 1 does not continue.

  Therefore, when the amount of change in the rotational speed of the engine 1 is calculated, it is determined whether or not energy can be supplied using this amount of rotational speed change (step S3-5).

  First, a determination value for the amount of change in the rotational speed used for determining whether supply is possible is set (step S3-5-1). This can also be changed according to the rotational load acting on the engine 1.

  Next, the calculated change amount of the engine 1 and the determination value of the change amount of the engine speed are compared (step S3-5-2), and if larger than the set determination value, the energy supply is stopped. If it is small, the energy supply is continued.

  Next, another specific example of the engine state calculation (step S3-4) and the energy supply availability determination (step S3-5) according to the embodiment of the present invention will be described with reference to FIG.

  After the start request, ignition is performed on the air-fuel mixture in the cylinder 2 that was in the expansion stroke at the time of stoppage. However, in this case, sufficient combustion energy may not be obtained because the air-fuel mixture is not compressed.

  Therefore, it is preferable to separately handle the motion state of the engine 1 before and after the first ignition timing and the motion state of the engine 1 before and after the subsequent ignition timing.

  Therefore, in this specific example, the state of the engine 1 other than the ignition to the cylinder 2 that was in the expansion stroke at the time of stop is calculated. That is, it is determined that the ignition is to other than the cylinder 2 in the expansion stroke in the initial stage of the engine 1 (S3-4-11), and the rotation speed of the engine 1 at the time of ignition is calculated. Further, regarding the calculation of the engine speed after ignition, the engine speed is calculated when the piston position of the ignited cylinder 2 is ATDC 90 °. That is, it is determined whether or not the piston position in the expansion stroke of the ignited cylinder 2 is ATDC 90 ° (S3-4-31), and the rotational speed at that time is calculated (S3-4-4).

  Next, an example of the effect of the present invention relating to the start control will be described with reference to FIGS. 10, 11, 12, and 13. FIG. 10, 11, 12, and 13 show energy by the second or third energy supply means with respect to the rotational movement angle of the crankshaft 14 of the engine 1 when the engine 1 is started by a plurality of energy supply means. The presence / absence of supply (upper stage), the rotational speed of the engine 1 (middle stage), and the in-cylinder pressure (lower stage), which is the pressure in the cylinder of the engine 1, are shown. Note that the start is set at a crank angle of 90 ° of the crankshaft 14.

  First, FIG. 10 shows an example of the case where the energy supply by the first energy supply means is performed as required (no combustion failure). In this case, energy supply and stop by the second and third energy supply means are performed by supplying energy from the start start position (position at the crankshaft rotation angle of 90 °) as shown in FIG. The energy supply was stopped from the vicinity of the crankshaft rotation angle of 180 °, which is the ignition timing of the air-fuel mixture in the cylinder that was in the compression stroke in the initial state.

  Further, as shown in (A-3), the combustion pressure in the expansion stroke is generated in the vicinity of the crankshaft rotation angle of 100 °, and the combustion pressure in the cylinder that was initially in the compression stroke is in the vicinity of the crankshaft rotation angle of 180 °. It has occurred and combustion by the first energy supply means can be realized.

  Thus, the first energy supply means supplies energy intermittently. When the energy supply by the first energy supply means and the second and third energy supply means is sufficiently performed in this way, the ignition timing (crankshaft rotation angle) of the cylinder mixture in the compression stroke in the initial state It can be seen that the rotational speed difference between the rotational speed at 180 [deg.] And the rotational speed at the time when the crankshaft 14 rotates 90 [deg.] (Crankshaft rotational angle 270 [deg.]) Extends to about 100 rpm (A-2). In this case, the rotation of the engine 1 continues (A-2), and the engine 1 can be completely started.

  Next, FIG. 11 is an example of the case where the energy supply by the first energy supply means is not performed as required (there is a combustion failure). In this case, the energy supply and stop by the second and third energy supply means are the same as (A-1) in FIG. 10, and as shown in (B-1) in FIG. Energy was supplied from a position at a rotation angle of 90 °, and the energy supply was stopped from the vicinity of a crankshaft rotation angle of 180 °, which is the ignition timing for the air-fuel mixture in the cylinder that was initially in the compression stroke.

  In addition, as shown in (B-3), combustion pressure in the expansion stroke is generated in the vicinity of the crankshaft rotation angle of 100 °. However, in the cylinder that was in the compression stroke in the initial state, only the pressure due to compression is cranked. It occurs in the vicinity of the shaft rotation angle of 180 °, and no combustion pressure is generated. This means that a failure has occurred in the combustion by the first energy supply means.

  Thus, if the energy supply by the first energy supply means and the second and third energy supply means is insufficient, the ignition timing (crankshaft rotation) of the cylinder mixture in the compression stroke in the initial state The rotation speed difference between the rotation speed at the angle 180 ° and the rotation speed at the time when the crankshaft 14 rotates 90 ° (crankshaft rotation angle 270 °) thereafter only occurs up to about 40 rpm (B-2).

  In this example, since it is not determined from the rotation state of the engine 1 that the energy supply is insufficient, the energy supply is insufficient, and the rotation of the engine 1 cannot be maintained (B-2). Cannot be started automatically.

  Next, the effects of the present invention are shown in FIGS. FIG. 12 shows an example of a result obtained by applying the present invention when energy supply by the first energy supply means is not performed as required (with combustion failure).

  As shown in (C-3), the combustion pressure in the expansion stroke is generated in the vicinity of the crankshaft rotation angle of 100 °, but only the pressure due to compression in the cylinder that was in the compression stroke in the initial state is the crankshaft rotation angle. It occurs in the vicinity of 180 °, and sufficient combustion pressure is not generated. This means that a failure has occurred in the combustion by the first energy supply means.

  According to the present invention, the rotational speed at the time of ignition of the air-fuel mixture in the cylinder that was in the compression stroke in the initial state (crankshaft rotation angle 180 °), and then the time when the crankshaft 14 rotated 90 ° (crankshaft rotation). When the rotation speed difference is less than a predetermined value, the second and third energy supply by the second and third energy supply means is continued. However, when the value is equal to or greater than the predetermined value, the second and third energy supply is stopped.

  Here, in order for the rotation of the engine 1 to continue, it can be seen from the results shown in FIG. 10 that the rotation speed difference needs to be about 100 rpm. Therefore, when the rotational speed difference in this determination is considered to be 100 rpm, in the case of FIG. 12, it is understood that this condition is satisfied as shown in (C-2).

  Accordingly, the energy supply and stop by the second and third energy supply means are performed by supplying energy from the start start position (position at the crankshaft rotation angle of 90 °) as shown in FIG. At the position (crankshaft rotation angle 270 °) rotated 90 ° from the ignition timing (crankshaft rotation angle 180 °) of the air-fuel mixture in the cylinder that was in the compression stroke in the state, the above-described rotation speed difference is determined. The second and third energy supply is stopped.

  In FIG. 12, even when a combustion failure occurs in the first energy supply means, the state is determined from the amount of change in the rotational speed of the engine 1, so that the rotation of the engine 1 can be continued, It can be started well. In particular, even in the case of poor combustion, the engine 1 can be started without excessive energy supply by the second and third energy supply means.

  Next, FIG. 13 shows another example of the result obtained by applying the present invention when the energy supply by the first energy supply means is not performed as required (with combustion failure).

  As shown in (D-3), the combustion pressure in the expansion stroke is generated in the vicinity of the crankshaft rotation angle of 100 °, but only the pressure due to compression in the cylinder that was in the compression stroke in the initial state is the crankshaft rotation angle. It occurs in the vicinity of 180 °, and sufficient combustion pressure is not generated. This means that a failure has occurred in the combustion by the first energy supply means.

  According to the present invention, the number of revolutions at the time of ignition of the air-fuel mixture of the cylinder that was in the compression stroke in the initial state (ignition 1: crankshaft rotation angle 180 °), and then the time when the crankshaft 14 rotated 90 ° ( A rotation speed difference with a rotation speed at a crankshaft rotation angle of 270 ° is calculated, and when the rotation speed difference is equal to or less than a predetermined value, the second and third energy supply means by the second and third energy supply means If the supply is continued and is above a predetermined value, the second and third energy supplies are stopped.

  Here, in order for the rotation of the engine 1 to continue, it can be seen from the results shown in FIG. 10 that the rotation speed difference needs to be about 100 rpm.

  Therefore, if the rotational speed difference in this determination is considered to be 100 rpm, in the case of FIG. 13, as shown in (D-2), the rotational speed change amount is 1 = 50 rpm, and it is understood that this condition is not satisfied. . Accordingly, the energy supply by the second and third energy supply means is continued.

  Then, the rotation speed difference between the rotation speed at the next ignition time (ignition 2: crankshaft rotation angle 360 °) and the rotation speed at the time when the crankshaft 14 rotates 90 ° (crankshaft rotation angle 450 °) is calculated. It is calculated and it is determined again whether or not it is a predetermined rotational speed difference (100 rpm) or more. In this case, as shown in FIG. 13 (D-2), the rotational speed variation 2 is 100 rpm, which satisfies the second and third energy supply stop conditions.

  Therefore, the energy supply and stop by the second and third energy supply means is performed by supplying energy from the start start position (position of the crankshaft rotation angle 90 °) as shown in FIG. At the position (crankshaft rotation angle 450 °) rotated 90 ° from the ignition point of the cylinder that was in the intake stroke in the state (ignition 2: crankshaft rotation angle 360 °), the above-described rotation speed difference is determined. The second and third energy supply is stopped.

  In FIG. 13, when combustion failure occurs in the first energy supply means, the state is determined from the amount of change in the rotation speed of the engine 1, so that the rotation of the engine 1 can be continued, and the engine 1 is It can be started well.

  In particular, even in the case of poor combustion, the engine 1 can be started without excessive energy supply by the second and third energy supply means.

  In FIGS. 12 and 13, both are cases where a combustion failure has occurred in the first energy supply means, but according to the present invention, according to each state from the rotational speed change amount and the rotational speed difference of the engine 1. Thus, it is possible to appropriately stop the supply by the second and third energy supply means and realize the optimum energy supply / stop control necessary for starting.

  Further, it is not necessary to accurately estimate the energy supplied by the second and third energy supply means, and no additional sensor is required for estimation, so that it is possible to realize start control at low cost. is there.

  As described above, according to the present embodiment, the state of motion of the engine 1 can be determined from the rotational speed without accurately estimating the supply energy by combustion, the supply energy by the starter, and the supply energy by the starter generator. Since the energy to be supplied is stopped accordingly, the energy necessary for starting is appropriately supplied to the engine 1, and the engine 1 can be started smoothly without waste.

  Further, even if the supply energy by combustion, the supply energy by the starter, and the supply energy by the starter / generator cannot be accurately controlled, the motion state of the engine 1 is determined from the rotational speed, and the supplied energy is stopped accordingly. The energy required for starting is appropriately supplied to the engine 1 and the engine 1 can be started smoothly without waste, so there is no need to use a high-performance starter or starter generator that performs torque control. An engine starting system can be constructed at a low cost.

  As described above, since the energy consumed at the time of starting can be minimized, it is suitable for the case where the engine 1 is repeatedly stopped and started frequently, such as when idling stop is executed. Further, the present invention is not limited to the restart at the time of idling stop, and can also be applied at the start corresponding to the ON operation of the ignition key, for example.

  In addition, the present invention can be applied to all cases where the internal combustion engine is started, such as when the engine is restarted in a hybrid vehicle using both the internal combustion engine and the electric motor.

  In addition, a second starter or the like is used as an auxiliary energy supply unit that compensates for the shortage of energy supply to the internal combustion engine by the first energy supply unit that starts the internal combustion engine using the energy of combustion of fuel by in-cylinder injection. Energy supply means and a third energy supply means such as a starter / generator and the like. Therefore, the shortage of energy supply to the internal combustion engine at the time of starting is supplied to the second energy supply means and the third energy supply means. The energy supply means can share the supply current supplied to each of the second energy supply means and the third energy supply means. Accordingly, the individual deterioration of the second energy supply unit and the third energy supply unit is suppressed. In addition, fail safe is achieved when either one of the second energy supply unit and the third energy supply unit fails.

  In the second energy supply means (starter), since it is necessary to mesh with the pinion of the starter with the ring gear attached to the crankshaft, energy supply is started in a state where the crankshaft is not completely stopped. However, when a belt-driven ISG is used as the third energy supply means (starter / generator), this is because the motor and the crankshaft are always connected by the transmission belt, so that the crankshaft is completely The energy supply can be started even when the vehicle is not stopped.

  Therefore, the second energy supply means and the third energy supply means can be used properly according to the state of the engine at the start of energy supply (whether or not the rotation of the crankshaft is completely stopped). .

  Although the method in the start control unit 91 has been described above, the stop control method performed by the stop control unit 92 that is important for starting is also described.

  FIG. 14 shows a flow of an embodiment of stop control performed by the stop control means 92 using the starter generator 22 that performs the third energy supply control.

  When the stop control is started (S4-1), torque control by the starter / generator is started (S4-2). Here, it is determined whether the rotation speed of the crankshaft is a predetermined rotation speed or a predetermined angle (S4-3). When the condition is satisfied, the starter / generator outputs a predetermined torque command (torque 1) (S4-4).

  Next, it is determined again whether the rotation speed of the crankshaft is a predetermined rotation speed or a predetermined angle (S4-5). When the condition is satisfied, the starter / generator outputs a predetermined torque command (torque 2) (4-6).

  Furthermore, it is determined again whether the rotation speed of the crankshaft is a predetermined rotation speed or a predetermined angle (S4-7). If the condition is satisfied, the starter / generator outputs a predetermined torque command (torque 3) (4-8).

  Finally, it is determined again whether the rotation speed of the crankshaft is a predetermined rotation speed or a predetermined angle (S4-9). When the condition is satisfied, the starter / generator control is completed (S4-10). .

  In the above description, the torque command of the starter / generator is set in three stages, but it may be a constant torque or a two-stage torque command.

  FIG. 15 shows an example of a time chart of a torque command in the stop control using the starter / generator 22 shown in FIG.

  Stop control is started at time t1. Next, the torque command is determined from the rotation speed, the rotation angle, etc., and the torque command becomes the first torque at time t1. Next, the torque command is changed to the second torque at time t2 based on the same determination.

  Similarly, the determination is made at time t3 and the torque is changed to the third torque. Finally, the starter / generator control is completed at time t4. In the example of FIG. 15, the first and second torques are constant, and the third torque is set to decrease with time. This torque setting is preferably changed according to the load torque around the engine shaft.

  FIG. 16 shows an example of the crank angle variation result when the four-cylinder engine 1 is stopped when the stop control shown in FIG. 15 is not applied and FIG. 17 is applied. The horizontal axis is the crank angle, and the vertical axis is the frequency.

  In the four-cylinder engine, the stop positions suitable for starting are crank angles around 90 ° and around 270 ° shown in FIGS. As shown in FIG. 16, although stop frequency peaks exist around 90 ° and around 270 °, it can be seen that the stop positions vary as a whole. On the other hand, as shown in FIG. 17, by introducing the stop control of FIG. 15, the stop frequency can be concentrated around 90 ° and 270 °, and stable stop control can be realized. .

  As described above, according to the present invention, it is not necessary to calculate the energy supplied at the time of starting by each energy supply means, and by determining the motion state generated by the energy supplied at the time of starting, Since some of the stops are performed, the second and third supply energy can be minimized without calculating the supplied energy accurately, and a stable start can be realized without causing a start failure. In addition, the noise at the start can be reduced. Furthermore, since it is not necessary to add a sensor for estimating the supply energy with high accuracy and to use high-performance energy means, the starting system can be constructed at low cost.

1 is a schematic configuration diagram showing an internal combustion engine applied with a starter according to an embodiment of the present invention. The schematic diagram of the control unit which is the starting device of the internal-combustion engine concerning one embodiment of the present invention. The block diagram which shows the detail of the principal part of the starting device of the internal combustion engine which concerns on one Embodiment of this invention. The flowchart which shows the outline | summary of the stop / start control method of the internal combustion engine which concerns on one Embodiment of this invention. The flowchart which shows the outline | summary of the starting method of the internal combustion engine which concerns on one Embodiment of this invention. The flowchart which shows the outline | summary of another example of the starting method of the internal combustion engine which concerns on one Embodiment of this invention. The flowchart which shows the detail of the processing flow of 1st energy supply control which is one Embodiment of this invention. The flowchart of the process which calculates the state of the internal combustion engine which concerns on one Embodiment of this invention, and the state of an internal combustion engine. The flowchart of another process which calculates the state of the internal combustion engine which concerns on one Embodiment of this invention, and the state which determines the state of an internal combustion engine. The chart which shows the change of the 2nd and 3rd energy supply / stop at the time of internal combustion engine starting, an engine speed, and a cylinder pressure. The chart which shows another of the change of the 2nd and 3rd energy supply / stop at the time of internal combustion engine starting, an engine speed, and a cylinder pressure. The chart which shows the change of the 2nd and 3rd energy supply / stop, engine speed, and in-cylinder pressure in the internal combustion engine start at the time of implementing this invention. FIG. 5 is another chart showing second and third energy supply / stop, engine speed, and in-cylinder pressure changes when the internal combustion engine is started when the present invention is implemented. The flowchart which performs engine stop control using a starter generator. A time chart of a torque command when engine stop control is performed using a starter generator. The graph which shows the example of the dispersion | variation result of the crank angle at the time of the stop of a 4-cylinder engine regarding the case where stop control is performed without using a starter generator. The graph figure which shows the example of the dispersion | variation result of the crank angle at the time of the stop of a 4-cylinder engine regarding the case where stop control is performed using a starter generator.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Internal combustion engine, engine 2 Cylinder 3 Piston 4 Fuel injection valve 6 Spark plug 9 Intake valve 10 Exhaust valve 13 Throttle valve 14 Crankshaft 17 Starter motor (2nd energy supply means)
DESCRIPTION OF SYMBOLS 19 Control unit 22 Electric motor 91 Start control means 911 Movement state determination means 912 Energy supply control means 92 Stop control means

Claims (6)

In a state where the internal combustion engine is stopped, fuel is injected into the cylinders in the expansion stroke and ignited, combustion is sequentially generated from the cylinders in the expansion stroke, and the combustion engine is utilized by utilizing the energy of the combustion. First energy supply means for starting;
Second energy supply means for starting the internal combustion engine by applying rotational torque to the crankshaft of the internal combustion engine from the outside;
Third energy supply means for starting the internal combustion engine by applying a rotational torque from the outside to the crankshaft of the internal combustion engine in a system different from the second energy supply means;
A motion state determination means for determining a motion state of the internal combustion engine;
When starting the internal combustion engine, energy is supplied from all of the first energy supply means, the second energy supply means, and the third energy supply means to the internal combustion engine to start the internal combustion engine. Energy supply control means for stopping the supply of energy to the internal combustion engine by the second energy supply means and the third energy supply means based on the determination result by the movement state determination means after the start of the movement of Have
The motion state determination means is based on the difference between the rotational speed of the internal combustion engine at the time of ignition of the first energy supply means and the rotational speed at the time when the crank angle of the internal combustion engine changes by a predetermined rotational angle from the ignition time. It is determined that the rotational state of the internal combustion engine is maintained,
The energy supply control means stops the energy supply to the internal combustion engine by the second energy supply means and the third energy supply means when it is determined by the motion state determination means that the rotation continues. A starting device for an internal combustion engine. The motion state determination means is configured to detect the rotational speed of the internal combustion engine when the first energy supply means ignites a cylinder that is in a compression stroke while the internal combustion engine is stopped, and the internal combustion engine from the ignition time. 2. The starting device for an internal combustion engine according to claim 1 , wherein it is determined that the rotational state of the internal combustion engine is maintained from a difference in rotational speed at a time when the crank angle changes by a predetermined rotational angle. Said second energy supplying means, characterized in that the starter motor is constituted by the starter and a gear mechanism or gear selection, said third energy supply unit is a starter generator for always-by belt transmission The starter for an internal combustion engine according to claim 1 or 2. In a state where the internal combustion engine is stopped, fuel is injected into the cylinders in the expansion stroke and ignited, combustion is sequentially generated from the cylinders in the expansion stroke, and the combustion engine is utilized by utilizing the energy of the combustion. The first energy supply means for starting, the second energy supply means for starting the internal combustion engine by applying rotational torque to the crankshaft of the internal combustion engine from the outside, and the second energy supply means are different from each other. A third energy supply means for starting the internal combustion engine by applying a rotational torque to the crankshaft of the internal combustion engine from the outside,
When starting the internal combustion engine, energy is supplied from all of the first energy supply means, the second energy supply means, and the third energy supply means to the internal combustion engine to start the internal combustion engine. After the start of the movement, the movement state of the internal combustion engine is determined, and the supply of energy to the internal combustion engine by the second energy supply unit and the third energy supply unit is stopped based on the determination result ,
The determination of the state of motion of the internal combustion engine is based on the rotational speed of the internal combustion engine at the time of ignition of the first energy supply means and the rotational speed at the time when the crank angle of the internal combustion engine has changed by a predetermined rotational angle from the ignition time. It is determined from the difference that the rotation state of the internal combustion engine is continued, and when it is determined that the rotation continues, the supply of energy to the internal combustion engine by the second energy supply unit and the third energy supply unit is stopped. A method of starting an internal combustion engine characterized by the above. The determination of the motion state of the internal combustion engine is performed by determining the rotational speed of the internal combustion engine at the time when the first energy supply means ignites a cylinder that is in the compression stroke when the internal combustion engine is stopped, and the time from the ignition time. 5. The method for starting an internal combustion engine according to claim 4 , wherein it is determined that the motion state of the internal combustion engine is continued from a difference in rotational speed at a time when the crank angle of the internal combustion engine changes by a predetermined rotational angle. Said second energy supplying means, characterized in that the starter motor is constituted by the starter and a gear mechanism or gear selection, said third energy supply unit is a starter generator for always-by belt transmission A method for starting an internal combustion engine according to claim 4 or 5 .

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