JP2020165343A - Engine starting device - Google Patents

Abstract

To provide an engine starting device that can start an engine even when a crankshaft is locked due to an event of sticking where a piston cannot pass over the compression top dead center when the crankshaft is driven in a reverse rotation direction at engine start up.SOLUTION: When a start control unit 80 detects that a crankshaft 51 is locked in staring an engine E, the start control unit controls a starter motor M to be driven in a reverse rotation direction and a normal rotation direction repeatedly to evacuate from the locked state and starts the engine E.SELECTED DRAWING: Figure 9

Description

The present invention relates to an engine starting device capable of smoothly starting an engine when the engine is started by a starter motor (including a starter and a generator).

Vehicles, including motorcycles, are currently generally equipped with a four-stroke engine, and when the engine is started, the crankshaft is rotated (cranked) by the starter motor, and the piston compresses top dead center. The engine can be started by exceeding. At this time, as the piston approaches the compression top dead center, the force (reaction force) that the pressure in the cylinder acts in the direction of pushing down the piston gradually increases, and before the compression top dead center, the maximum transit torque ( Maximum cranking torque) is required.

Therefore, for example, in Patent Document 1, in order to reduce the load on the starter motor, when the engine is started, the starter motor reverses the crankshaft to the vicinity of the exhaust top dead center and starts normal rotation from that position. It is disclosed that so-called swingback control is performed in which the inertial force of the piston is obtained and the maximum cranking torque is overcome by the combined force of the inertial force and the torque of the starter motor (Patent Document 1 [0998]).

Japanese Patent No. 4076108

When starting the engine, it is necessary to apply rotational torque to the crankshaft so that the piston exceeds the compression top dead center as described above, but in order to improve startability, a decompression mechanism is applied to the engine. Often adopted. This decompression mechanism is a well-known technology, and is a mechanism that can release the pressure in the cylinder when the engine is started to smoothly perform cranking, and is sometimes abbreviated as decompression. ..

Then, in order to further improve the startability of the engine, it is preferable to make the closing angle of the decompression closer to the compression top dead center side, and by doing so, the torque required for cranking can be further reduced. , The engine can be started smoothly.

By the way, due to the so-called idle stop, which is when the vehicle is normally stopped by turning off the ignition switch by the occupant, or when the vehicle is stopped and the throttle opening is returned to a predetermined angle or less, the engine is automatically stopped. At the time of stop, the position where the piston stops is not constant.

Then, as shown in FIG. 10, when the closing angle of the decompression is positioned near the compression top dead center C / T (for example, −θd = −50 °), a predetermined angle on the opposite side (shown in FIG. 10). In the example, the negative pressure becomes high within 0 ° to + 3θd (+ 150 °), and if the piston happens to be located at such a position, the negative pressure in the cylinder will increase even if an attempt is made to swing back. Since it is in a high state, it cannot swing back, and even if it tries to rotate the crankshaft in the normal direction after that, the starting torque of the crankshaft will be the same when the battery voltage supplied to the starter motor is low. Since it loses to the negative pressure in the cylinder, the crankshaft does not move (hereinafter referred to as the locked state). Therefore, a technique for improving the startability of the engine when such a locked state occurs is desired. The area where the locked state occurs is called a closed area LA.

The present invention has been made in consideration of such a problem, and when the crankshaft is reversely driven at the time of starting the engine, a fitting phenomenon in which the piston cannot overcome the compression top dead center occurs and the crank is cranked. It is an object of the present invention to provide an engine starting device capable of improving engine startability even when the shaft falls into a locked state.

The engine starting device (10) of one aspect of the present invention is
A starter motor (M) that rotates the crankshaft (51) of the engine (E),
In an engine starting device (10) including a control unit (80) that controls the starter motor (M) and starts the engine (E).
When the control unit (80) detects that the crankshaft (51) is in the locked state when the engine (E) is started, the control unit (80) performs reverse rotation drive and forward rotation drive of the starter motor (M). The locked state is repeatedly released to start the engine (E).

According to the present invention, when the piston cannot overcome the compression top dead center when the engine is started and the crankshaft is locked, the starter motor is repeatedly driven in reverse and forward rotation to release the locked state. By doing so, the lock of the crankshaft is released and the startability of the engine is improved.

FIG. 1 is a side view of a vehicle equipped with the engine starting device according to the embodiment. FIG. 2 is a sectional view taken along line II-II of FIG. FIG. 3 is a circuit block diagram of the control system of the ACG starter motor. FIG. 4 is a circuit block diagram showing a configuration of a main part in the ECU related to drive control of the ACG starter motor. FIG. 5 is an explanatory view of a motor stage using a motor angle sensor. FIG. 6 is a flowchart (1/2) provided for explaining the operation of the engine starting device. FIG. 7 is a flowchart (1/2) provided for explaining the operation of the engine starting device. FIG. 8 is a diagram corresponding to the crank angle and the valve lift amount provided for explaining the operation of the engine starting device. FIG. 9 is a block diagram schematically showing the processing of the flowchart. FIG. 10 is a diagram corresponding to the crank angle and the valve lift amount used for explaining the problem.

An embodiment of the engine starting device according to the present invention will be described in detail below with reference to the accompanying drawings.

[Constitution]
FIG. 1 is a side view of a vehicle 11 equipped with the engine starting device 10 according to the embodiment.

The vehicle 11 is a scooter-type motorcycle as an example, and when the vehicle 11 is stopped during traveling, the engine E is automatically stopped, and then the starter switch (starter SW) 35 is pressed by the driver's right hand. Or, when the throttle grip 18R is rotated, the ACG starter motor [starter / generator in which the starter motor as a starter and the AC generator (alternator) as a generator are integrally configured] M It has an engine automatic stop start function (idle stop function) that automatically drives and restarts the engine E. In this embodiment, the ACG starter motor M is a three-phase brushless motor.

The front portion of the vehicle body and the rear portion of the vehicle body of the vehicle 11 are connected via a floor portion 12, and the vehicle body frame is generally composed of a head pipe 13, a down tube 14, and a main pipe 15. The fuel tank (not shown) is supported by the main pipe 15, and the seat 17 is arranged above the main pipe 15.

An ECU 80 as a control unit is arranged in front of the head pipe 13.

The upper part of the head pipe 13 is connected to the steering handle (bar handle) 18, and the lower part is pivotally supported by the front fork 16 that pivotally supports the front wheel FW.

A main switch (main SW) 45 that switches between an off position and an on position is provided on the driver side of the cover portion of the head pipe 13 and the front fork 16.

The steering handle 18 is composed of a non-rotating grip 18L that is gripped by the left hand and a throttle grip 18R that is gripped and rotatable by the right hand. A starter SW35 that can be operated with the thumb while the driver holds the throttle grip 18R is provided in the vicinity of the throttle grip 18R.

A bracket 128 is welded to the lower end of the rising portion of the main pipe 15, and a hanger bracket 132 of the swing unit 20 is swingably connected and supported on the bracket 128 via a link member 134.

The swing unit 20 is equipped with a single-cylinder 50 cc 4-cycle engine E in front of the swing unit 20.

As is known, the engine E has a crankshaft that reciprocates a piston in a cylinder, and the crankshaft is rotationally driven (cranked) by an ACG starter motor M when the engine E is started. As described above, the ACG starter motor M also serves as a starter motor and an AC generator (alternator).

A belt-type continuously variable transmission 136 is configured from the engine E to the rear, and the rear wheel RW is pivotally supported by a reduction mechanism 138 provided at the rear of the continuously variable transmission 136 via a centrifugal clutch.

A cushion 141 is interposed between the upper end of the speed reduction mechanism 138 and the upper bent portion of the main pipe 15. A fuel injection device (FI) 142 connected to an intake pipe 140 extending from the engine E and an air cleaner 144 connected to the upstream side of the fuel injection device 142 are arranged at the front portion of the swing unit 20.

FIG. 2 is a sectional view taken along line II-II of FIG. The swing unit 20 has a crankcase 74 including a right case 75 on the right side in the vehicle width direction and a left case 76 on the left side in the vehicle width direction. The crankshaft 51 is rotatably supported by bearings 53 and 54 fixed to the crankcase 74. A connecting rod 73 is connected to the crankshaft 51 via a crankpin 52.

The left case 76 also serves as a transmission chamber case for the continuously variable transmission 136, and a belt drive pulley composed of a movable side pulley half body 60 and a fixed side pulley half body 61 is attached to the left end portion of the crankshaft 51. ing.

The fixed-side pulley half body 61 is fastened to the left end of the crankshaft 51 by a nut 77. Further, the movable side pulley half body 60 is spline-fitted to the crankshaft 51 so as to be slidable in the axial direction. A V-belt 62 is wound between the pulley halves 60 and 61.

On the right side of the movable pulley half body 60, the lamp plate 57 is fixed to the crankshaft 51. The slide piece 58 attached to the outer peripheral end of the lamp plate 57 is engaged with the lamp plate sliding boss 59 formed in the axial direction at the outer peripheral end of the movable pulley half body 60. Further, a tapered surface is formed on the outer peripheral portion of the lamp plate 57 so as to be inclined toward the movable side pulley half body 60 toward the outer side in the radial direction, and a plurality of tapered surfaces are formed between the tapered surface and the movable side pulley half body 60. Weight roller 63 is housed.

When the rotational speed of the crankshaft 51 increases, the weight roller 63 moves radially outward due to centrifugal force. As a result, the movable pulley half body 60 moves to the left in the drawing and approaches the fixed pulley half body 61, and as a result, the V-belt 62 sandwiched between the two pulley half bodies 60 and 61 is radially outward. It moves and its winding diameter increases. On the rear side of the swing unit 20, a driven pulley (not shown) having a variable winding diameter of the V-belt 62 corresponding to both pulley half bodies 60 and 61 is provided. The driving force of the engine E is automatically adjusted by the belt transmission mechanism and transmitted to the rear wheel RW via a centrifugal clutch and a reduction mechanism 138 (see FIG. 1) (not shown).

An ACG starter motor M is arranged inside the right case 75. The ACG starter motor M is arranged inside the outer rotor 71, which is fixed to the tapered portion of the tip of the crankshaft 51 with a mounting bolt 120, rotates integrally with the crankshaft 51, and has a magnet 78 fixed in the circumferential direction. It is composed of a stator 72 that is installed, fixed to the right case 75 with a mounting bolt 121, and wound with a phase coil. A radiator 68 and a cover member 69 having a plurality of slits formed are attached to the right side of the blower fan 65, which is fixed to the outer rotor 71 by mounting bolts 67.

A sprocket 55 around which a cam chain for driving a camshaft (not shown) is wound is fixed to the crank shaft 51 between the ACG starter motor M and the bearing 54. Further, the sprocket 55 is integrally formed with a gear 56 that transmits power to a pump (not shown) that circulates oil.

FIG. 3 is a circuit block diagram of the control system of the ACG starter motor M. In FIG. 3, the same or equivalent portions as those shown in FIGS. 1 and 2 are designated by the same reference numerals.

The ECU 80 serves as a three-phase inverter when the ACG starter motor M is rotationally driven by the electric power of the battery B, and a converter (three-phase) when the battery B is charged by the three-phase induced electromotive force generated by the ACG starter motor M. A drive circuit 81 that functions as a full-wave rectifying bridge) is included. Further, the ECU 80 adjusts the output of the drive circuit 81 functioning as a converter to a planned regulated voltage (regulator operating voltage: for example, 14.5 V) to charge the battery B, and the drive circuit 81. A drive control unit 85 that supplies an on / off signal voltage to the control terminals, and a swingback control unit (reverse / normal rotation control unit) that reverses the crankshaft 51 to a predetermined position when the engine is started and then starts normal rotation, as described later. ) 90, and an engine start status determination unit 84 and a stage determination unit 83, which will be described later, respectively. As a whole, the ECU 80 functions as a start control unit of the engine E and the like.

The ECU 80 includes a fuel injection device (Fuel Injector) 142, a motor angle sensor 29, an ignition coil 21, a throttle opening sensor 23, a fuel sensor 24, a seat SW25 for detecting the seated state of an occupant, an idle stop control permission switch 26, and cooling. The water temperature sensor 127 and the ignition pulsar 30 are connected, and detection signals from each part are input to the ECU 80. A spark plug 22 is connected to the secondary side of the ignition coil 21. Three motor angle sensors 29 are arranged at intervals of 120 ° in the circumferential direction of the stator 72 in order to detect the position of the magnet 78 of the outer rotor 71.

Further, a starter relay 34, a starter SW35, a stop SW36, 37, a standby indicator 38, a fuel indicator 39, a vehicle speed sensor 40, and a headlight 42 are connected to the ECU 80. The headlight 42 is provided with a dimmer SW43. Electric power is supplied from the battery B to each of the above components via the main fuse 44 and the main SW45.

FIG. 4 is a circuit block diagram showing a configuration of a main part (regulator 82 and the like are omitted) in the ECU 80 related to drive control of the ACG starter motor M.

The drive circuit 81 is configured by connecting three sets (FET Q1 and Q2, FET Q3 and Q4, FET Q5 and Q6) of two power MOSFETs connected in series in parallel, and constitutes a U that constitutes a stator 72 of the ACG starter motor M from the battery B. A phase current is supplied to each phase coil of the phase coil, the V phase coil, and the W phase coil.

Diodes D1 to D6 are connected to the FETs Q1 to Q6 in parallel in the direction opposite to the flow direction of the FETs Q1 to Q6.

The control terminal of the drive circuit 81 is a gate terminal of FET Q1 to Q6, and an on / off signal voltage of FET Q1 to Q6 is applied to the gate terminal at a predetermined timing from the drive control unit 85.

A smoothing capacitor 86 is arranged between the battery B and the drive circuit 81.

In the present embodiment, the MOSFET is exemplified as the switching element constituting the drive circuit 81, but the present invention is not limited to this, and a power transistor or the like may be used.

Based on the output signals of the motor angle sensor 29 and the ignition pulser 30, the stage determination unit 83 divides the two rotations of the crankshaft 51 into 72 stages (720 degrees) of the crankshaft stages # 0 to 71, and the motor angle sensor Based on the output signal of 29, the motor stage MS is divided into 0 to 5 described below, and the current stage (crankshaft stage # 0 to 71 and the motor stage MS) is determined.

FIG. 5 is an explanatory diagram of the motor stage MS. The motor stage MS is determined by the combination of the high level "1" and the low level "0" of each axis pulse of the U, V, and W phases from the motor angle sensor 29. For example, when the combination of UVW is "011", the motor stage MS is MS = 0, and when the combination of UVW is "001", the motor stage MS is MS = 1. In this case, the stage determination unit 83 determines that the motor stage MS is in forward rotation when the motor stage MS is continuous in the forward order of 0, 1, 2, ... 5, 0 ... In the time series. If the sequence is continuous in the reverse order of 3, ..., 0, 5, ..., it is determined to be reverse.

Further, the determination of the crankshaft stages # 0 to 71 by the stage determination unit 83 is based on the output value of the intake pressure sensor (PB sensor) (not shown) that measures the pressure of the intake pipe (not shown) after the engine E is started. Until the stroke determination (determination of the front and back of two rotations of the crankshaft) is completed based on the above, one rotation of the crankshaft 51 is performed by a 360-degree motor stage divided into 36 stages of stages # 0 to 35. The ignition pulsar 30 is provided integrally with the motor angle sensor 29 of the ACG starter motor M, and detects the rotation angle of the ACG starter motor M attached to the crankshaft 51.

When the starter switch 35 is operated from the state where the engine E is stopped, the swingback control unit 90 of the ECU 80 reverses the engine E to a predetermined position once, that is, swings back and then starts normal rotation. By doing so, the approach period to the compression top dead center C / T is lengthened, and the rotation speed of the crankshaft 51 when first overcoming the compression top dead center C / T is increased by "swingback control at engine start". It is possible to execute. According to the swingback control at the time of starting the engine, it is possible to improve the startability when the engine E is started by the starter switch 35.

When the ACG starter motor M is driven in the forward rotation, the swingback control unit 90 that functions as the reverse rotation / normal rotation control unit sends a forward rotation drive command to the drive control unit 85. At this time, the drive control unit 85 supplies the on / off signal voltage at the predetermined timing (order) described below in response to the forward rotation drive command to the control terminals of the FETs Q1 to Q6 of the drive circuit 81.

With this on / off signal voltage, the coils of each phase of the UVW phase of the stator 72 are energized by 120 °, respectively, and the [Q1 / Q6 on (U → V) phase coil] → [Q1 / Q4 on (U → W) phase Coil] → [Q5 / Q4 on (V → W) phase coil] → [Q5 / Q2 on (V → U) phase coil] → [Q3 / Q2 on (W → U) phase coil] → [Q3 / Q6 on (W → V) phase coil] UVW phase order allows a current whose energization pattern changes every 60 ° to flow.

As a result, the outer rotor 71 having the magnet 78 is driven in the forward rotation by the electromagnetic force. In this case, the crankshaft 51 connected to the outer rotor 71 rotates forward at the same time.

The FETs other than the FETs that are driven on are driven off. For example, when the (U → V) phase coil is energized, the FETs Q1 and Q6 are driven on, and the remaining FETs Q2 and Q5 are driven off. The same applies to the following description.

When the ACG starter motor M is reversely driven, the swingback control unit 90 that functions as the reverse / forward rotation control unit sends a reverse rotation drive command to the drive control unit 85. At this time, the drive control unit 85 supplies the on / off signal voltage at the predetermined timing (order) described below in response to the reverse drive command to the control terminals of the FETs Q1 to Q6 of the drive circuit 81.

With this on / off signal voltage, the coils of each phase of the UVW phase of the stator 72 are energized by 120 °, respectively, and the [Q3 / Q6 on (W → V) phase coil] → [Q3 / Q2 on (W → U) phase Coil] → [Q5 ・ Q2 on (V → U) phase coil] → [Q5 ・ Q4 on (V → W) phase coil] → [Q1 ・ Q4 on (U → W) phase coil] → [Q1 ・ Q6 on (U → V) phase coil] WVU phase order (reverse order of UVW phase order) allows a current whose energization pattern changes every 60 ° to flow. As a result, the outer rotor 71 having the magnet 78 is reversely driven by the electromagnetic force. In this case, the crankshaft 51 connected to the outer rotor 71 reverses at the same time.

Further, the ECU 80 can execute idle stop control for temporarily stopping the engine E when a predetermined condition is satisfied when the vehicle is stopped such as waiting for a signal. As a predetermined condition for starting the idle stop, for example, when the idle stop control permission SW26 is ON and the seat SW25 is ON, the seating of the occupant is detected, and the vehicle speed detected by the vehicle speed sensor 40 is equal to or less than a predetermined value (for example, 5 km / h). , The engine speed detected by the ignition pulsar 30 is equal to or less than a predetermined value (for example, 2000 rpm), and the throttle opening detected by the throttle opening sensor 23 is equal to or less than a predetermined value (for example, 5 degrees) for a predetermined time. It is said that when has passed.

Then, when the throttle opening becomes equal to or higher than a predetermined value by the rotation operation of the throttle grip 18R during the idle stop, the contact of the starter relay 34 is closed by the ECU 80, or the contact of the starter relay 34 is turned on when the starter SW35 is turned on. Is closed and DC power is supplied from the battery B to the drive circuit 81.

In this state, the drive circuit 81 is driven in three phases from the swingback control unit 90 of the ECU 80 through the drive control unit 85, so that the crankshaft 51 is swingback driven through the ACG starter motor M to rotate and restart the engine E. It is configured to start.

[motion]
Next, with respect to the vehicle 11 equipped with the engine starting device 10 basically configured as described above, the flow charts of FIGS. 6 and 7 and the crank angle / valve of FIG. 8 are mainly focused on the operation of the engine starting device 10. It will be described with reference to the lift amount correspondence diagram and the block diagram of FIG. 9 which schematically shows the processing of the flowchart.

For convenience of understanding, FIGS. 6, 7, and 9 are provided with schematic views relating to the states (i) to (vi) described later showing the rotation direction of the starter motor M and the like. The states (i) to (vi) are also given in FIG.

In FIG. 8, the valve lift amount, which is the amount at which the exhaust valve and the intake valve are opened, is in an overlapping state near the exhaust top dead center O / T near the crank angle of 360 °, and the compression top dead center C / T (720). The exhaust valve that was closed is slightly opened by the decompression mechanism (decompression cam + exhaust valve) to reduce the force required for compression at the position immediately before (°). The decompression mechanism operates by the decompression cam only when the engine is started, and does not operate while the engine is running.

In the example of FIG. 8, the decompression closing end angle is set to the crank angle −θd ° (−θd = −50 °). In this engine E, at least one of the exhaust valve and the intake valve is open between the position where the exhaust valve rises and the tappet clearance intersects and the decompression closing end angle −θd °, and the decomp closing end angle −θd ° Both the exhaust valve and the intake valve are closed in the range of approximately + 3θd ° (+ 3θd = 150 °).

In engine E, when the crankshaft 51 (piston) stops in the range (0 ° to + 3θd ° = 0 ° to 150 °) from the crank angle 0 ° to the intersection of the exhaust valve and the tappet clearance, it will be explained with reference to FIG. As described above, since both valves are closed, the negative pressure is increased, and due to this increase in negative pressure, the piston is pressed against the cylinder head side by the atmospheric pressure, causing a fitting phenomenon. It was found that LA may occur and the crankshaft 51 may be locked.

Then, for example, when the crankshaft 51 is located in the closed region LA when the engine E is started or idle stopped [state (i) (see FIG. 8)], in step S1 of FIG. 6, the starter SW23 When is operated from OFF to ON, or when the throttle opening becomes equal to or more than a predetermined value (predetermined angle) by the rotation operation of the throttle grip 18R, in step S2, the starter relay 34 ( The contacts in Fig. 3) are changed from the normally open state to the closed state.

More specifically, when the starter switch 35 is pressed, a current is supplied from the battery B to the coil of the starter relay 34 through the starter SW35, so that the contacts of the starter relay 34 are closed. Further, when the throttle opening detected by the throttle opening sensor 23 becomes equal to or more than a predetermined angle by the rotation operation of the throttle grip 18R, the ECU 80 supplies a current from the output port to the coil of the starter relay 34 to start the starter. The contact of the relay 34 closes.

When the processing status of steps S1 and S2 is determined by the engine start status determination unit 84 and it is detected that the contact of the starter relay 34 is closed, the processing by the swingback control unit 90 in step S3. The drive circuit 81 is driven below through the drive control unit 85 by 120 ° energization control that changes the energization pattern every 60 ° in the phase order (reverse order) of the WVU described above. Due to the energization control in the phase order (reverse order) of the WVU, the current corresponding to each UVW phase coil of the ACG starter motor M flows by the electric power of the battery B, and the outer rotor 71 of the ACG starter motor M is reversely driven by the electromagnetic force. .. As a result, the crankshaft 51 integrally connected to the outer rotor 71 is urged (reverse drive) in the reverse direction [state (ii): see FIG. 8].

Next, in step S4, the crankshaft 51 cannot escape from the closed region LA from the transition state of the motor stage MS based on the output signals (U phase, V phase, W phase) of the motor angle sensor 29 in the stage determination unit 83. Detection of whether or not it is in the locked state (lock detection) is performed.

Here, at the time of starting / swingback when the lock state is not set, for example, when the crank angle is located at MS = 4 for the first motor stage MS, the motor stage MS changes from MS = 4 to MS = 3. Since it shifts in the reverse direction, it can be judged that it is not in the locked state.

On the other hand, at the time of starting in the locked state, for example, when the crank angle is located at MS = 2 in the first motor stage MS, the motor stage MS remains at MS = 2 even if a swingback is attempted. On the contrary, the motor stage MS is MS = 2 even if the normal rotation is attempted. As described above, when the motor stage MS does not change even if the swingback and normal rotation of the crankshaft 51 are attempted, the engine start status determination unit 84 can determine that the crankshaft 51 is in the locked state.

In step S3, the reverse drive was first driven, but in step S4, the engine start status determination unit 84 detects (reverse lock state detection) [state (ii), step S4: YES]. Then, in the next step S5, the drive circuit 81 is changed through the drive control unit 85 through the drive control unit 85 under the processing by the swingback control unit 90, and the energization pattern is changed every 60 ° in the above-mentioned UVW phase order (normal order) of 120 °. It is driven by energization control. Due to the energization control in the phase order (normal order) of the UVW, the current corresponding to each UVW phase coil of the ACG starter motor M flows by the electric power of the battery B, and the outer rotor 71 of the ACG starter motor M is driven in the forward direction by the electromagnetic force. Will be done. As a result, the crankshaft 51 integrally connected to the outer rotor 71 is urged (forward rotation drive) in the forward rotation direction [state (iii): see FIG. 8].

Similarly, in the same manner, in step S6, when the lock is detected and the locked state is detected [state (iii), step S6: YES], in step S7, further through the ACG starter motor M. The crankshaft 51 is driven in reverse.

In step S8, the lock is detected again and the locked state is detected [state (iv), step S8: YES], and in step S9, the crankshaft 51 rotates forward again through the ACG starter motor M. It is driven, and lock detection is performed again in step S10.

When the locked state is detected in step S10 (step S10: YES), the locked state is detected in the second reverse drive, so that the crankshaft 51 is reversed / positive through the ACG starter motor M. The repetitive processing of the rolling drive is stopped, and the stop processing [state (vii)] is performed in step S11.

After this stop processing, the contact of the starter relay 34 is changed from the closed state to the normally open state by releasing the drive of the starter relay 34 in step S24 (coupler c in FIG. 6 → coupler c in FIG. 7). It is returned and the process ends without the start of engine E being achieved. At this time, for example, it is displayed on the meter panel that the engine E has not started.

In the flowchart of FIG. 6, the number of times of repeated control of reverse rotation → forward rotation drive (also referred to as pendulum control for convenience of understanding) until the stop processing in step S11 is performed is twice (the number of reverse rotations is two times). ), But the number of repetitions (pendulum control) may be increased.

On the other hand, when the locked state is not detected in steps S4 and S8 during the reverse drive (steps S4 and S8: NO), the step of FIG. 7 (coupler a in FIG. 6 → coupler a in FIG. 7). After performing the swingback process [state (vi)] in S21 to position the crankshaft 51 in the low load range of the cranking torque, the crankshaft 51 is driven in the forward rotation by the ACG starter motor M in step S22. In this case, the crankshaft 51 passes through the exhaust top dead center O / T, overcomes the compression top dead center C / T by the combined force of the inertial force of the piston and the torque of the starter motor M, and enters the combustion range. The engine E will start at. After starting the engine E, by ending the driving of the starter relay 34 in step S24, the contacts of the starter relay 34 return from the closed state to the normally open state, and the pendulum control process at the time of starting the engine E ends.

If the lock state is not detected by the stage determination unit 83 and the engine start status determination unit 84 in steps S6 and S10 during which the forward rotation drive is continuing, the swingback control unit 90 changes the drive control unit 85. By continuing the forward rotation drive of the ACG starter motor M through the engine, the crankshaft 51 passes through the next exhaust top dead center O / T, and the next compression is performed by the inertial force of the piston and the torque of the starter motor M. Since the top dead center C / T is overcome and the combustion range is entered, the engine E is started in step S23 (coupler b in FIG. 6 → coupler b in FIG. 7). After starting the engine E, the current supply to the coil of the starter relay 34 is terminated in step S24. As a result, the contacts of the starter relay 34 are returned from the closed state to the normally open state, and the pendulum control process at the time of starting the engine E is completed.

After the engine E is started, a three-phase induced electromotive force is generated in the UVW phase coil by the outer rotor 71 of the ACG starter motor M connected to the crank shaft 51 rotated by the engine E, and the three-phase induced electromotive force is generated. The electric power is set to a predetermined DC voltage at the smoothing capacitor end of the drive circuit 81, for example, 14.5V by the three-phase full-wave rectifying bridge composed of the diodes D1 to D6, the regulator 82, and the smoothing capacitor 86, and the battery. B is charged.

[Invention that can be grasped from the embodiment]
Here, the inventions that can be grasped from the above embodiments will be described below. For convenience of understanding, the components are marked with the reference numerals used in the embodiments in parentheses, but the components are not limited to those with the reference numerals.

The engine starting device (10) according to the present invention is
A starter motor (M) that rotates the crankshaft (51) of the engine (E),
In an engine starting device (10) including a control unit (80) that controls the starter motor (M) and starts the engine (E).
When the control unit (80) detects that the crankshaft (51) is in the locked state when the engine (E) is started, the control unit (80) performs reverse rotation drive and forward rotation drive of the starter motor (M). The locked state is repeatedly released to start the engine (E).

According to the present invention, when the piston cannot overcome the compression top dead center at the start of the engine (E) and the crankshaft (51) is locked, the starter motor (M) is driven in reverse and positive. By repeating the rolling drive to release the locked state, the crankshaft (51) is unlocked and the startability of the engine (E) is improved.

In this case, the control unit (80) reversely drives the starter motor (M) only when the crankshaft (51) is locked.

By controlling in this way, it is not necessary to unnecessarily repeat the reverse rotation drive and the forward rotation drive of the starter motor (M), so that the time required for starting the engine (E) can be shortened.

Here, the starter motor (M) is an ACG starter motor (M).

Since the present invention can be integrated by sharing the starter motor and the generator, the cost as a product can be reduced, and in the case of a motorcycle, it can be applied to a scooter type vehicle. it can.

Further, the ACG starter motor (M) is a three-phase brushless motor, includes an angle sensor (29) for detecting the rotational position of the ACG starter motor (M), and is based on the detection value of the angle sensor (29). It is determined whether or not the locked state is released.

As a result, the locked state can be easily detected using the existing angle sensor (29).

In this case, the motor stage (MS) is formed based on the detection value of the angle sensor (29), and in the locked state based on the presence or absence of movement of the motor stage (MS) when the engine (E) is started. Determine if it exists.

The locked state can be easily detected by using the existing angle sensor (29).

A decompression was provided, and the decompression was provided near the compression top dead center (−θd: decompression).

Thereby, the startability in the normal time can be improved.

The present invention is not limited to the above-described embodiment, and based on the contents described in this specification, for example, a vehicle in which an ACG starter motor (M) is divided into a starter (starter motor) and a generator (AC generator). It goes without saying that various configurations can be adopted, such as being applied to.

10 ... Engine starter 11 ... Vehicle 29 ... Motor angle sensor 34 ... Starter relay 51 ... Crankshaft 80 ... ECU
83 ... Stage determination unit 84 ... Engine start status determination unit 85 ... Drive control unit 90 ... Swingback control unit B ... Battery E ... Engine LA ... Sealed area M ... ACG starter motor

Claims (6)

A starter motor (M) that rotates the crankshaft (51) of the engine (E),
In an engine starting device (10) including a control unit (80) that controls the starter motor (M) and starts the engine (E).
When the control unit (80) detects that the crankshaft (51) is in the locked state when the engine (E) is started, the control unit (80) performs reverse rotation drive and forward rotation drive of the starter motor (M). An engine starting device (10) that repeatedly releases the locked state and starts the engine (E). In the engine starting device (10) according to claim 1.
The control unit (80) is an engine starting device (10) that reversely drives the starter motor (M) only when the crankshaft (51) is locked. In the engine starting device (10) according to claim 1 or 2.
The starter motor (M) is an engine starting device (10) which is an ACG starter motor (M). In the engine starting device (10) according to claim 3.
The ACG starter motor (M) is a three-phase brushless motor, includes an angle sensor (29) for detecting the rotational position of the ACG starter motor (M), and is said to be based on a value detected by the angle sensor (29). An engine starting device (10) that determines whether or not the locked state has been released. In the engine starting device (10) according to claim 4.
Whether or not the motor stage (MS) is formed based on the detected value of the angle sensor (29) and is in the locked state based on the presence or absence of movement of the motor stage (MS) when the engine (E) is started. Engine starting device (10) for determining whether or not. In the engine starting device (10) according to any one of claims 1 to 3.
An engine starting device (10) provided with a decompression, the decompression provided near the compression top dead center.

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