JP4480590B2 - Internal combustion engine start control method - Google Patents

Description

  The present invention includes a power transmission mechanism with an auto tensioner in which an endless transmission belt is stretched between pulleys of a crankshaft, a rotation shaft of a motor / generator, and rotation shafts of other accessories. The present invention relates to start control of an internal combustion engine.

  A motor / generator used in this type of internal combustion engine can be driven as a starter motor to start the internal combustion engine, or can generate assist torque as an assist motor, and can also be driven as a generator during operation of the internal combustion engine. Is.

  In an internal combustion engine equipped with a power transmission mechanism with an auto tensioner, when the motor / generator is driven as a starter motor to start the internal combustion engine, the rotation between the rotation shaft of the motor / generator and the crankshaft is simultaneously performed. As a result, a strong tension acts momentarily on the transmission belt that transmits power, so the auto tensioner operates greatly on the side where the transmission belt is loosened, and then the tension on the transmission belt suddenly operates greatly on the tension side. May be violent and power transmission may not be performed smoothly.

  Therefore, when driving the motor / generator as a starter motor, it has been proposed to lock the auto tensioner so that it does not operate in the direction of loosening the transmission belt. Without proper tension, the transmission belt may slip immediately after the motor / generator is driven.

In order to eliminate such problems, there is an example (see Patent Document 1) proposed by the same applicant.
JP 2003-314322 A

  In the method disclosed in Patent Document 1, when a motor / generator is driven as a starter motor, a reverse torque is generated in the motor / generator before the motor / generator is driven. Loosen the transmission belt and operate the auto tensioner in the tensioning direction of the transmission belt, and lock the operation in the loosening direction to ensure sufficient tension on the transmission belt.

  In this way, with the transmission belt maintaining sufficient tension, a positive torque is generated in the motor / generator to start the internal combustion engine, so that the transmission / slip of the transmission belt immediately after the motor / generator is driven by the positive torque is avoided. The engine can be started.

  After the internal combustion engine is started and the drive of the motor / generator as a starter motor is stopped, the lock on the auto tensioner is released to prevent the continuous tension from being applied to the transmission belt. The decline is also avoided.

  By the way, the rotation state of the crankshaft is detected by a crank angle sensor, a TDC sensor, a cylinder sensor, and the like, and the fuel injection timing and ignition timing of each cylinder are determined based on the detection timing of these sensors.

When a reverse torque is generated in the motor / generator before driving the motor / generator as a starter motor as in the method described in Patent Document 1, the crankshaft also rotates in reverse via the transmission belt during this period. detection signals of the sensors by reverse rotation of, will actuate the devices such as the fuel injection system and ignition device effectively worked each cylinder, before the internal combustion engine is started in normal, Ya extra fuel injection When ignition is executed and the motor / generator is actually started by generating a positive torque, there is a possibility that proper starting may be hindered due to an obstacle such as excessive combustion fuel.

  The present invention has been made in view of the above points, and the object of the present invention is to prevent slippage of the transmission belt at the start of the internal combustion engine so that it can be smoothly started and is appropriate without performing extra work. The point is to provide an internal combustion engine start control method capable of starting reliably.

In order to achieve the above object, according to the first aspect of the present invention, an endless transmission belt is stretched between pulleys of a crankshaft of an internal combustion engine, a rotation shaft of a motor / generator, and a rotation shaft of other auxiliary machinery. The power transmission mechanism to which power is transmitted is provided with an auto tensioner that applies a predetermined tension to the transmission belt and can be locked only in the direction of loosening the transmission belt, and locks the operation of the auto tensioner in the contraction direction. In this state, reverse torque is generated in the motor / generator, and when the transmission belt is loosened and the auto tensioner is operated in the tension direction, the state is maintained, and then a positive torque is generated to generate internal combustion. in starting control method for an internal combustion engine to start the engine, the electrical angle detecting the electrical angular position of the rotating shaft of the motor-generator To detect the forward rotation and reverse rotation of the rotary shaft of the motor generator on the basis of the electrical angular position of location sensor detects the rotation shaft reverse rotation of the motor-generator by the occurrence of reverse torque of the motor-generator If the detection is performed based on the electrical angle position detected by the electrical angle position sensor, the detection signals of various crank sensors for detecting the rotation state of the crankshaft of the internal combustion engine for engine operation timing control are invalidated, and the motor When detecting that the rotation shaft of the motor / generator rotates positively due to generation of positive torque of the generator based on the electrical angle position detected by the electrical angle position sensor, the detection signals of the various crank sensors are validated. The internal combustion engine starts driving the equipment whose timing is controlled based on the detection signal. And an internal combustion engine start control method is dynamic control.

According to a second aspect of the present invention, an endless transmission belt is stretched between pulleys of a crankshaft of an internal combustion engine, a rotation shaft of a motor / generator, and a rotation shaft of other auxiliary machinery to transmit power. The mechanism is provided with an auto tensioner that applies a predetermined tension to the transmission belt and can be locked only in a direction in which the transmission belt is loosened, and the motor / generator is locked in an operation in a contraction direction of the auto tensioner. When the auto tensioner is operated in the tension direction by taking advantage of the fact that the transmission belt is loosened when the transmission belt is loosened, the state is maintained, and then a positive torque is generated to start the internal combustion engine. in the control method, and it outputs a reverse rotation command signal to generate a reverse torque to the motor-generator, the engine operation timing Invalidates the detection signals of the various crank sensor for detecting a rotational state of the crankshaft of the internal combustion engine for controlling, and outputs a forward rotation command signal to generate a positive torque of the motor-generator, said crankshaft from the time the output After a lapse of a predetermined time when it can be presumed that the engine has started to rotate positively, the detection signals of the various crank sensors are validated to start driving the equipment whose timing is controlled based on the detection signals, and the internal combustion engine is controlled to start. This is an internal combustion engine start control method.

According to a third aspect of the present invention, an endless transmission belt is stretched between pulleys of a crankshaft of an internal combustion engine, a rotation shaft of a motor / generator, and a rotation shaft of other auxiliary machinery, and the power is transmitted. The mechanism is provided with an auto tensioner that applies a predetermined tension to the transmission belt and can be locked only in a direction in which the transmission belt is loosened, and the motor generator is locked in a state where the operation of the auto tensioner in the contraction direction is locked. When the auto tensioner is actuated in the tension direction by taking advantage of the fact that the transmission belt is loosened when the transmission belt is loosened, the state is maintained, and then the internal combustion engine is started by generating a positive torque. in the control method, if there is an output of the start command signal, the predetermined time can be estimated that the crankshaft has started to ensure normal rotation Until the predetermined time has elapsed, the detection signals of the various crank sensors for detecting the rotation state of the crankshaft of the internal combustion engine are invalidated, and the detection signals of the various crank sensors are validated after the predetermined time has elapsed. This is an internal combustion engine start control method in which the drive of a device whose timing is controlled based on the detection signal is started and the internal combustion engine is controlled to start.

According to the internal combustion engine start control method according to claim 1, when the electric angular position sensor detects that the rotation shaft of the motor / generator is reversely rotated due to generation of reverse torque of the motor / generator, the crankshaft is estimated to be reversely rotated. Then, the detection signals of the various crank sensors for detecting the rotation state of the crankshaft are invalidated, and unnecessary driving of the device whose timing is controlled based on the detection signals is stopped, and the motor When the electrical angular position sensor detects that the generator's rotating shaft is rotating forward, the forward rotation of the crankshaft can be estimated and the detection signals of the various crank sensors are validated, and the timing of the equipment whose timing is controlled on the basis of the detected signals. Since the internal combustion engine is started by starting driving, it is appropriate without performing extra work before starting It is possible to perform a reliable start-up.

  In a state where the operation of the auto tensioner in the contracting direction is locked, a reverse torque is generated in the motor / generator, and when the transmission belt is loosened, the auto tensioner is operated in the tension direction, and this state is maintained. Since the internal combustion engine is started by generating a positive torque in a state where a sufficient tension is applied to the transmission belt, slippage of the transmission belt immediately after the generation of the positive torque is prevented and a smooth start can be performed.

According to the internal combustion engine start control method according to claim 2 , when a reverse rotation instruction signal for generating reverse torque is output to the motor / generator, it is estimated that the crankshaft is reversely rotated, and various cranks for detecting the rotation state of the crankshaft are detected. When the detection signal of the sensor is invalidated and the unnecessary drive of the device whose timing is controlled based on the detection signal is stopped, and a positive rotation instruction signal for generating a positive torque of the motor / generator is output, a predetermined time has elapsed since the output. After that, it is possible to estimate the normal rotation of the crankshaft, and by enabling the detection signals of various crank sensors to start driving the equipment controlled in timing based on the detection signals, the internal combustion engine is started. An appropriate and reliable start can be performed without extra work.

  With the operation of the auto tensioner in the contraction direction locked, a reverse torque is generated in the motor / generator, and when the transmission belt is loosened, the auto tensioner is operated in the tension direction. Since the internal combustion engine is started by generating a positive torque in a state where a sufficient tension is applied to the transmission belt, slippage of the transmission belt immediately after the generation of the positive torque is prevented and a smooth start can be performed.

According to the internal combustion engine start control method according to claim 3, when there is an output of a start command signal, it is estimated that the crankshaft is reversely rotated for a fixed time, and detection signals of various crank sensors for detecting the rotation state of the crankshaft. Is disabled and extra drive of the device whose timing is controlled based on the same detection signal is stopped, and it is estimated that the crankshaft is in the forward rotation after a predetermined time, and the detection signals of various crank sensors are enabled. As a result, the driving of the device whose timing is controlled based on the detection signal is started and the internal combustion engine is started. Therefore, an appropriate and reliable start can be performed without performing extra work before starting.

  With the operation of the auto tensioner in the contraction direction locked, a reverse torque is generated in the motor / generator, and when the transmission belt is loosened, the auto tensioner is operated in the tension direction. Since the internal combustion engine is started by generating a positive torque in a state where a sufficient tension is applied to the transmission belt, slippage of the transmission belt immediately after the generation of the positive torque is prevented and a smooth start can be performed.

Hereinafter, an embodiment according to the present invention will be described with reference to FIGS.
FIG. 1 is a schematic right side view of an internal combustion engine 1 to which the internal combustion engine start control method according to the present embodiment is applied.
The internal combustion engine 1 is an overhead camshaft type water-cooled in-line four-cylinder four-stroke cycle internal combustion engine, and the internal combustion engine 1 is mounted on a vehicle in a state where the axial direction of the crankshaft 3 is oriented in the vehicle width direction of the vehicle. A driving system for auxiliary machinery is arranged on the right side of the internal combustion engine 1.

  A crankshaft 3 is rotatably supported by a crankcase of an engine body 2 of the internal combustion engine 1, and a camshaft 4 is pivotally supported by a cylinder head. A drive sprocket 5 and a camshaft 4 fitted to the crankshaft 3 are supported. The timing chain 7 is suspended between the driven sprocket 6 fitted to the camshaft 4, and the camshaft 4 makes 1/2 rotation with respect to one rotation of the crankshaft 3.

  Since it is a four-stroke cycle internal combustion engine, the crankshaft 3 rotates twice and the camshaft 2 rotates once in one cycle in which the piston has four strokes (intake stroke, compression stroke, combustion stroke, exhaust stroke).

  Auxiliary equipment such as a power steering hydraulic pump 11, a motor / generator 12, a water pump 13, and an air conditioning compressor 14 are fixedly supported in order from the top by an auxiliary equipment bracket 10 attached to the front side of the engine body 2.

  Rotating shafts 11a, 12a, 13a, 14a of the auxiliary machines 11, 12, 13, 14 are parallel to the crankshaft 3 and are respectively provided with hydraulic pump pulleys 11b, motor / generator pulleys 12b, A water pump pulley 13b and a compressor pulley 14b are fitted on the same surface.

  As shown in FIG. 1, between the crank pulley 3a fitted to the end protruding to the right side of the crankshaft 3 and the hydraulic pump pulley 11b, motor / generator pulley 12b, water pump pulley 13b, compressor pulley 14b, An endless transmission belt 15 is stretched over.

A tensioner pulley 16 is disposed between the crank pulley 3a and the hydraulic pump pulley 11b to apply tension to the transmission belt 15.
The tensioner pulley 16 is pivotally supported by a pin 16a at the tip of one arm portion 18a of a bell crank 18 whose bent portion is pivotally supported by a support shaft 17.

The tip of the other arm portion 18b of the bell crank 18 has a pin 22b attached to a bracket 22a of one inner case 22 of a hydraulic auto tensioner 20 composed of an outer case 21 and an inner case 22 which are slidably fitted to each other and extend and contract. It is connected through.
The bracket 21a of the other outer case 21 of the hydraulic auto tensioner 20 is pivotally attached to the accessory bracket 10 by a support shaft 21b.

  The rotation of the transmission belt 15 relative to the rotation of the crankshaft 3 (crank pulley 3a) in the internal combustion engine 1 (clockwise rotation in FIG. 1) and the normal rotation as the motor of the motor / generator 12 (clockwise in FIG. 1). When the tensioner pulley 16 acts on the tension side of the transmission belt 15 with respect to the rotation of the belt, and the hydraulic auto tensioner 20 extends with the inner case 22 protruding from the outer case 21, the bell crank 18 Thus, the tensioner pulley 16 can press the transmission belt 15 to increase the tension, and when the hydraulic auto tensioner 20 contracts in reverse, the transmission belt 15 can be loosened and the tension can be decreased.

  As shown in FIG. 2, the basic structure of the hydraulic auto tensioner 20 is such that a bottomed cylindrical outer case 21 and an inner case 22 which are opposed to each other are slidably fitted to each other, and an oil storage chamber is formed inside. 23, and the outer case 21 and the inner case 22 are urged in a direction away from each other by a spring 25 interposed therebetween.

Inside the oil storage chamber 23, a hydraulic chamber 24 is formed by a combination of a piston 26 and a cylinder 27 provided integrally with each of the outer case 21 and the inner case 22, and the hydraulic chamber 24 filled with oil and the oil are stored. A leak passage 30 communicates with the oil storage chamber 23 along the bottom surface.
A control valve (check valve) 31 is interposed in the leak passage 30, and an electromagnetic solenoid 32 that drives the control valve 31 is provided in the inner case 22.

  The leak passage 30 includes a large-diameter portion 30a on the hydraulic chamber 24 side and a small-diameter portion 30b on the oil storage chamber 23 side, and the boundary surface between the large-diameter portion 30a and the small-diameter portion 30b forming the valve chamber forms a valve seat 30c and is spherical. The control valve 31 moves along the large-diameter portion 30a, contacts and separates from the valve seat 30c, and opens and closes the leak passage 30.

The control valve 31 is urged toward the valve seat 30c by a spring 35.
On the other hand, the sliding rod 33 coaxially coupled to the drive shaft 32a of the electromagnetic solenoid 32 is urged by the spring 34 so that the tip protrudes from the control valve 31 and away from the valve seat 30c. When the spring force is stronger than that of the spring 35 and the electromagnetic solenoid 32 is demagnetized, the spring force of the spring 34 wins, and the sliding rod 33 pierces the control valve 31 to open the leak passage 30.
When the electromagnetic solenoid 32 is excited (actuated), the sliding rod 33 that has struck the control valve 31 is retracted, and the control valve 31 abuts against the valve seat 30c by the spring 35 to close the leak passage 30.

  The hydraulic auto tensioner 20 has the above-described structure. Normally, the electromagnetic solenoid 32 is demagnetized, and the control valve 31 does not function as a check valve and opens the leak passage 30, and the transmission belt. When the tension of 15 is reduced and the tension is lowered, the inner case 22 is extended by the spring 25 with respect to the outer case 21 and extended, and through the leak passage 30 opened by the expansion of the hydraulic chamber 24, the oil reservoir chamber 23 and the hydraulic chamber By flowing oil into 24, the outer case 21 and the inner case 22 are extended with a small damping force, and the transmission belt 15 can be pressed to recover an appropriate tension.

  On the contrary, when the tension of the transmission belt 15 increases, the oil leaks from the hydraulic chamber 24 to the oil storage chamber 23 through the leak passage 30, and the outer case 21 and the inner case 22 are slowly contracted with a large damping force. It is possible to prevent excessive tension from being applied to the transmission belt 15.

When the electromagnetic solenoid 32 is energized to retract the sliding rod 33 so that the control valve 31 functions as a check valve, the outer case 21 and the inner case 22 can be extended, but the control valve is in the contraction direction. 31 can close the leak passage 30 to prevent contraction and lock only the contraction direction.
In the power transmission system of the auxiliary machinery in which the hydraulic auto tensioner 20 applies tension to the transmission belt 15 as described above, the electromagnetic solenoid 32 of the hydraulic auto tensioner 20 is controlled by an engine controller that performs engine operation control. 40 are going at the same time.

An overall schematic configuration diagram of the engine operation control system will be described with reference to FIG.
The engine controller 40 controls the timing of the fuel injection device 41 and the ignition device 42 of each cylinder, outputs signals such as a start command to the other motor controller 45, and drives the electromagnetic solenoid 32 of the hydraulic auto tensioner 20. Is controlling.

  The engine controller 40 receives detection signals such as a brake switch and an accelerator opening, and also receives detection signals from three types of crank sensors that detect the rotation state of the crankshaft 3.

  That is, the cylinder sensor 51, the TDC sensor 52, and the crank angle sensor 53 are all pickup coils arranged around the camshaft 4, and the rotation state of the crankshaft 3 is detected by the rotation state of the camshaft 4. is doing.

Referring to FIG. 4 (1), the cylinder sensor 51 detects a protrusion 51t protruding on a predetermined circumference of the camshaft 4 at a predetermined position, and uses it as a reference timing for one cycle in which the camshaft 4 makes one rotation. The projection of the first cylinder is detected and the pulse signal is transmitted in a crank rotation state in which the piston of the first cylinder shows a compression top dead center.
The cylinder sensor 51 transmits one pulse per cycle.

The TDC sensor 52 detects four protrusions 52t arranged at equal intervals (90-degree angle) on a predetermined circumference of the camshaft 4 at predetermined positions, and determines the compression top dead center of the pistons of the four cylinders as the first and second. Detection is performed in the order of the third, fourth and second cylinders, and a pulse signal is transmitted.
That is, the TDC sensor 52 transmits 4 pulses per cycle.

The crank angle sensor 53 detects 24 protrusions 53t arranged at equal intervals (15 degree angle) on a predetermined circumference of the camshaft 4 at a predetermined position, and outputs a pulse signal at a 30 degree angle as the crankshaft 3 rotates. send.
That is, the crank angle sensor 53 transmits 24 pulses in one cycle, that is, 6 pulses in 1/4 cycle.

When the piston of the first cylinder is at the compression top dead center, the cylinder sensor 51, the TDC sensor 52, and the crank angle sensor 53 simultaneously detect the protrusions 51t, 52t, and 53t and transmit pulses.
A timing chart of pulse signals of the cylinder sensor 51, the TDC sensor 52, and the crank angle sensor 53 is shown in FIG.

  However, none of the cylinder sensor 51, the TDC sensor 52, and the crank angle sensor 53 can detect the rotation direction of the crankshaft 3, and the rotation direction of the crankshaft 3 can be detected by combining the detection pulses of the sensors. Cannot be determined.

On the other hand, the rotating shaft 12a of the motor / generator 12 is provided with a resolver 55 which is an electrical angular position sensor.
The motor / generator 12 has 16 magnetic poles, and as shown in FIG. 5, an electrical angle of 360 degrees corresponds to a mechanical angle of 45 degrees. With reference to FIG. The detection value of the electrical angle position of the resolver 55 is increased stepwise from 0 degree to 360 degrees, and the detected waveform has a sawtooth shape.

  In addition, referring to FIG. 5 (2), the detection value of the resolver 55 at the time of reverse rotation repeatedly decreases stepwise from an electrical angle of 360 degrees to 0 degrees, and the detected waveform is at the time of forward rotation and the direction of teeth. The sawtooth shape is reversed.

The detection signal of the resolver 55 is output to the motor controller 45.
When the motor controller 45 receives the detection signal of the resolver 55, the motor controller 45 analyzes the waveform of the detected electrical angle position value to determine whether the motor / generator 12 is rotating forward or backward as a motor, and rotating the motor forward The signal and the motor reverse rotation signal are output to the engine controller 40.

FIG. 6 shows a start control timing chart when the motor / generator 12 does not reversely rotate as a motor when the internal combustion engine 1 is started.
When the engine controller 40 outputs a start command signal to the motor controller 45, the motor controller 45 drives the motor / generator 12 to rotate forward as a motor.

  With the forward rotation of the motor / generator 12, the resolver 55 detects the electrical angle position of the rotation of the rotating shaft 12a, the motor controller 45 determines the direction of rotation, turns the motor forward rotation signal on, and turns the motor reverse rotation signal off. Output to the engine controller 40.

  When the forward rotation of the motor / generator 12 is transmitted through the transmission belt 15 and the crankshaft 3 rotates forward, the cylinder sensor 51, the TDC sensor 52, and the crank angle sensor 53 output detection pulse signals, respectively.

  The engine controller 40 inputs these detection pulse signals, drives and controls the fuel injection device 41 and the ignition device 42 based on the detection pulse signals, and detects the crank angle sensor 53 from the compression top dead center of the first cylinder. In the second pulse of the pulse signal, an operation command signal is output to the fuel injection device 41 of the fourth cylinder to execute fuel injection for the fourth cylinder, and the ignition device for the third cylinder at the next compression top dead center of the third cylinder. The operation command signal is output to 42, ignition of the third cylinder is executed, and fuel injection is executed for the second cylinder from the compression top dead center at the second pulse by the detection pulse signal of the crank angle sensor 53.

Subsequently, ignition of the fourth cylinder and fuel injection of the first cylinder are executed based on the compression top dead center of the fourth cylinder, and ignition of the second cylinder and second injection are performed based on the compression top dead center of the next second cylinder. Three cylinder fuel injection is performed.
The conventional start control method is to start the internal combustion engine 1 by repeatedly performing the above-described one cycle operation.

  In the start control by the engine controller 40 and the motor controller 45 according to the present embodiment, when a start command is output from the engine controller 40 to the motor controller 45, the motor controller 45 reversely rotates the motor generator 12 for a predetermined time, The actual internal combustion engine 1 is started by rotating.

  The rotation state of the motor / generator 12 is determined by the motor controller 45 decoding the electrical angle position signal detected by the resolver 55 and output as a motor forward rotation signal and a motor reverse rotation signal. The rotation state of the motor / generator 12 can be known, and the timing of the fuel injection device 41 and the ignition device 42 is controlled based on this rotation state.

  Hereinafter, the starting control by the engine controller 40 will be described based on the flowchart shown in FIG. 7 and the timing chart shown in FIG.

  First, when the engine controller 40 outputs a start command (step 1), the motor controller 45 causes the motor / generator 12 to drive in reverse rotation for a predetermined time, so that the process proceeds to step 2 where the electromagnetic solenoid of the hydraulic auto tensioner 20 is driven. Energize 32.

  As described above, by energizing the electromagnetic solenoid 32, the sliding rod 33 is retracted and the control valve 31 functions as a check valve. Therefore, the outer case 21 and the inner case 22 can be expanded but contracted. In the direction, the control valve 31 closes the leak passage 30 to prevent contraction and locks only the contraction direction.

  Referring to FIG. 3, when motor / generator 12 generates reverse torque and reversely rotates (in the direction of the broken line arrow in FIG. 3), the portion of transmission belt 15 to which tensioner pulley 16 of transmission belt 15 applies tension is referred to. Because it loosens, the outer case 21 and inner case 22 of the hydraulic auto tensioner 20 try to expand and secure sufficient tension, and since it is locked in the contraction direction, it will not contract once expanded, Tension is maintained.

  In this way, with the hydraulic auto tensioner 20 maintained in a sufficient tension by locking in the contraction direction, the motor / generator 12 generates a positive torque and enters the forward rotation to start the internal combustion engine 1. The slip of the transmission belt 15 immediately after the generator 12 is driven by the positive torque is avoided, and the internal combustion engine 1 can be started smoothly.

  After exciting the electromagnetic solenoid 32 in step 2, the motor forward rotation signal and the motor reverse rotation signal indicating the rotation state of the motor / generator 12 are read in step 3, and whether the motor / generator 12 is reversely rotated in step 4 or not. Is determined.

  When a start command is issued, the motor / generator 12 is rotated reversely for a predetermined time. Therefore, as shown in FIG. 8, the motor reverse rotation signal is turned on. During this time, the motor normal rotation signal is turned off. When the start command is received from, it is determined that the rotating shaft 12a of the motor / generator 12 is rotating in the reverse direction (step 4), and the process proceeds to step 6.

  In step 6, since the motor / generator 12 is reversely rotated, it is estimated that the crankshaft 3 is also reversely rotated, and each of the cylinder sensor 51, the TDC sensor 52, and the crank angle sensor 53 while the motor reverse rotation signal is in the ON state. The detection pulse signal of the sensor is invalidated (indicated by a one-dot chain line in FIG. 8).

  Therefore, there is no output of the operation command signal to the fuel injection device 41 and the ignition device 42 based on the detection pulse signal (indicated by a broken line in FIG. 8), and fuel injection and ignition are not executed while the motor reverse rotation signal is on. .

  In the example shown in FIG. 8, the fuel injection of the fourth cylinder is performed by invalidating the detection pulse signals of the cylinder sensor 51, the TDC sensor 52, and the crank angle sensor 53 while the motor reverse rotation signal is on. The operation command signal to the device 41 is not output.

  If the detection pulse signal while the motor reverse rotation signal is on is not invalidated and this operation command signal is output and fuel injection of the fourth cylinder is executed, the motor generator 12 generates a positive torque. When the motor reverse rotation signal is on, the operation command signal is output to the fuel injection device 41 of the fourth cylinder from the compression top dead center of the first cylinder with the detection pulse signal of the crank angle sensor 53 in the second pulse. Then, fuel injection is performed again on the fuel injection device 41 of the fourth cylinder, and there is a risk that the fourth cylinder will be excessively fueled, resulting in deterioration of combustion and exhaust gas.

  In this start control method, when the crankshaft 3 is estimated to be reversely rotated, it is possible to prevent the above-mentioned problems by preventing excessive fuel injection and ignition, and when the crankshaft 3 rotates forward. In addition, the internal combustion engine 1 can be started appropriately.

  Next, at step 7, the abnormality detection work of the detection pulse signals of the cylinder sensor 51, the TDC sensor 52, and the crank angle sensor 53 is not permitted, and the accuracy of abnormality detection is guaranteed.

  If it is determined in step 4 that the motor / generator 12 is not rotating in reverse, the process proceeds to step 5 to determine whether the motor / generator 12 is rotating forward, that is, whether the motor rotating signal is on. If it is not already turned on, the process proceeds to step 6 where the detection pulse signal of each sensor is invalidated and fuel injection and ignition are not executed. However, if the motor forward rotation signal is turned on, it is estimated that the crankshaft 3 is rotating forward. Then, the process proceeds to step 8 where the detection pulse signals of the cylinder sensor 51, the TDC sensor 52, and the crank angle sensor 53 are validated, and the operation command signals are output to the fuel injection device 41 and the ignition device 42 based on the detection pulse signals. (Indicated by a solid line in FIG. 8), fuel injection and ignition are executed.

As described above, since unnecessary fuel injection and ignition when it is estimated that the crankshaft 3 is rotating in the reverse direction are prevented, the internal combustion engine 1 can be started appropriately.
Then, in the next step 9, the execution of the abnormality detection operation of the detection pulse signals of the cylinder sensor 51, the TDC sensor 52, and the crank angle sensor 53 is permitted, and the abnormality detection is executed.

  After the internal combustion engine 1 is started, the electromagnetic solenoid 32 of the hydraulic auto tensioner 20 is demagnetized to prevent a large tension from being continuously applied to the transmission belt 15 and avoid a decrease in durability. ing.

  In the above embodiment, when there is a start command signal, reverse torque is generated in the motor / generator 12, the transmission belt 15 is loosened, and the hydraulic auto tensioner 20 is extended to lock the operation in the contraction direction. However, in an internal combustion engine that automatically stops (idle stop) when the vehicle stops and automatically restarts when the vehicle starts, the motor / generator 12 generates reverse torque when the idle stop condition is satisfied or after the condition is satisfied. Then, loosen the transmission belt 15 and extend the hydraulic auto tensioner 20 to lock the operation in the contraction direction, keep the tension of the transmission belt 15 sufficiently high, and when a start command is issued, start the motor from this state A positive torque may be generated in the generator 12 to start the internal combustion engine 1.

Next, start control according to another embodiment will be described based on a flowchart shown in FIG. 9 and a timing chart shown in FIG.
In the case of this start control, the electrical angle position sensor such as a resolver does not detect the electrical angle of the rotation of the motor / generator 12, but controls based on the rotation instruction signal of the motor controller 45 (except for the resolver 55, the control system). Is the same as that of the above embodiment, and the same reference numerals are used).

  This rotation instruction signal is a plus (+1) signal when instructing the motor / generator 12 to perform forward rotation, is a minus (-1) signal when instructing reverse rotation, and is not present when not instructing rotation. 0) signal.

Referring to FIG. 9, steps 11 and 12 are the same as steps 1 and 2, and when engine controller 40 outputs a start command (step 11), electromagnetic solenoid 32 of hydraulic auto tensioner 20 is excited ( Step 12) Lock only the contraction direction.
Then, in the next step 13, it is determined whether or not there is a reverse rotation instruction signal.

  When there is a start command, the motor controller 45 instructs the motor / generator 12 to drive in reverse rotation, so the reverse rotation instruction (-1) signal is immediately after the start command output, and the motor / generator 12 generates reverse torque. Then, the reverse rotation, the transmission belt 15 is loosened, the hydraulic auto tensioner 20 is extended to try to secure sufficient tension, and since it is locked in the contraction direction, it does not contract once expanded, Tension will be maintained.

  If it is determined in step 13 that there has been a reverse rotation instruction (-1) signal, the routine proceeds to step 16 where it is estimated that the motor / generator 12 is reversely rotated and the crankshaft 3 is also reversely rotated. , TDC sensor 52, and crank angle sensor 53, the detection pulse signals of each sensor are invalidated (indicated by a one-dot chain line in FIG. 10), and therefore, operation command signals to fuel injection device 41 and ignition device 42 based on the detection pulse signals There is no output (indicated by a broken line in FIG. 10), and fuel injection and ignition are not executed while the motor reverse rotation signal is on.

  Next, in step 17, the execution of the abnormality detection operation of the detection pulse signals of the cylinder sensor 51, the TDC sensor 52, and the crank angle sensor 53 is not permitted, and the accuracy of abnormality detection is guaranteed.

When it is determined in step 13 that the reverse rotation instruction (−1) signal has been lost, the process proceeds to step 14 to determine whether or not there is a normal rotation instruction (+1) signal.
While there is no forward rotation instruction (+1) signal, the routine jumps to step 16 and fuel injection or ignition is not executed.

  If there is a forward rotation instruction (+1) signal, the process proceeds to step 15 to determine the elapse of a predetermined time. Even if there is a forward rotation instruction (+1) signal, the process jumps to step 16 until the predetermined time elapses, and fuel injection or When the ignition is not yet executed and it is estimated that the crankshaft 3 is surely rotating forward after a predetermined time has passed, the routine proceeds to step 18, and each of the cylinder sensor 51, the TDC sensor 52, and the crank angle sensor 53 is detected. , The operation command signal is output to the fuel injection device 41 and the ignition device 42 based on the detection pulse signal (shown by the solid line in FIG. 10), fuel injection and ignition are executed, and the next step 19, the execution of the abnormality detection operation of the detection pulse signals of the cylinder sensor 51, the TDC sensor 52, and the crank angle sensor 53 is also permitted.

  As described above, unnecessary fuel injection and ignition when it is estimated that the crankshaft 3 is rotating in the reverse direction are prevented, and there is a forward rotation instruction (+1) signal. Since the fuel injection and ignition are started from the time when it is estimated that the engine is normally rotating, the internal combustion engine 1 can be appropriately started.

Next, start control of still another embodiment will be described based on the flowchart shown in FIG. 11 and the timing chart shown in FIG. 12 (the configuration of the control system is the same as that of the above embodiment, and the same reference numerals are used). .
In the case of the actual start control, if there is a start command of the engine controller 40, it is assumed that the motor controller 45 instructs the motor / generator 12 to perform the reverse rotation drive after a predetermined time has elapsed after instructing the motor / generator 12 to perform the reverse rotation drive. The timing is controlled based on the start command.

Referring to FIG. 11, when a start command is output (step 21), electromagnetic solenoid 32 of hydraulic auto tensioner 20 is excited (step 22), and only the contraction direction is locked.
Then, in the next step 23, it is determined whether a predetermined predicted time has elapsed.

  During this predetermined prediction time, the motor controller 45 instructs the motor / generator 12 to drive in reverse rotation, and the reverse rotation of the crankshaft 3 is estimated, and then the motor / generator 12 is instructed to drive in forward rotation. This is the estimated time that is estimated to start positive rotation reliably.

  Until it is determined at step 23 that the predetermined predicted time has elapsed, the routine proceeds to step 24, where it is estimated that the motor / generator 12 is reversely rotated and the crankshaft 3 is also reversely rotated, and the cylinder sensor 51, TDC sensor. 52, the detection pulse signal of each sensor of the crank angle sensor 53 is invalidated (indicated by a one-dot chain line in FIG. 12), and therefore, no operation command signal is output to the fuel injection device 41 and the ignition device 42 based on the detection pulse signal. (Indicated by a broken line in FIG. 12) While the motor reverse rotation signal is on, fuel injection and ignition are not executed, and detection of abnormality in detection pulse signals of the cylinder sensor 51, TDC sensor 52, and crank angle sensor 53 is detected. The execution of the work is not permitted (step 17), and the accuracy of abnormality detection is guaranteed.

  If it is determined in step 23 that the predetermined predicted time has elapsed, the process proceeds to step 26, in which the detection pulse signals of the cylinder sensor 51, TDC sensor 52, and crank angle sensor 53 are validated, and fuel injection based on the detection pulse signal is performed. Operation command signals are also output to the device 41 and the ignition device 42 (shown by solid lines in FIG. 12), fuel injection and ignition are executed, and in the next step 19, the cylinder sensor 51, the TDC sensor 52, and the crank angle sensor 53 Execution of the abnormality detection operation of the detection pulse signal of each sensor is also permitted.

  As described above, unnecessary fuel injection and ignition when it is estimated that the crankshaft 3 is rotating in the reverse direction are prevented, and the crankshaft 3 is normally rotated forward after a predetermined predicted time. Since the fuel injection and ignition are started from when it is reliably estimated, the internal combustion engine 1 can be appropriately started.

1 is a schematic right side view of an internal combustion engine to which an internal combustion engine start control method according to an embodiment of the present invention is applied. It is a figure which shows the basic structure of a hydraulic auto tensioner. It is a schematic block diagram of the whole internal combustion engine operation control system. It is a figure which shows the detection method and detection signal of a cylinder sensor, TDC sensor 2, and a crank angle sensor. It is a figure which shows the electrical angle position detection signal and the relationship between an electrical angle and a mechanical angle. It is a figure which shows the starting control timing chart in case a motor generator does not reversely rotate as a motor at the time of engine starting. It is a flowchart which shows the procedure of the starting control by an engine controller. It is a figure which shows the timing chart of the starting control. It is a flowchart which shows the procedure of the starting control by the engine controller which concerns on another embodiment. It is a figure which shows the timing chart of the starting control. Furthermore, it is a flowchart which shows the procedure of the starting control by the engine controller which concerns on another embodiment. It is a figure which shows the timing chart of the starting control.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Internal combustion engine, 2 ... Engine main body, 3 ... Crankshaft, 4 ... Camshaft, 5 ... Drive sprocket, 6 ... Driven sprocket, 7 ... Timing chain, 10 ... Auxiliary bracket, 11 ... Hydraulic pump for power steering, 12 ... motor generator, 13 ... water pump, 14 ... air conditioning compressor, 15 ... transmission belt, 16 ... tensioner pulley, 17 ... spindle, 18 ... bell crank,
20 ... Hydraulic auto tensioner, 21 ... Outer case, 22 ... Inner case, 23 ... Oil storage chamber, 24 ... Hydraulic chamber, 25 ... Spring, 26 ... Piston, 27 ... Cylinder, 30 ... Leak passage, 31 ... Control valve, 32 ... Electromagnetic solenoid, 33 ... Sliding rod, 34 ... Spring, 35 ... Spring,
40 ... engine controller, 41 ... fuel injection device, 42 ... ignition device, 45 ... motor controller, 51 ... cylinder sensor, 52 ... TDC sensor, 53 ... crank angle sensor, 55 ... resolver.

Claims (3)

A power transmission mechanism in which an endless transmission belt is stretched between pulleys of a crankshaft of an internal combustion engine, a rotation shaft of a motor / generator, and a rotation shaft of other auxiliary machinery is transmitted to a power transmission mechanism. And an auto tensioner that can be locked only in the direction of loosening the transmission belt.
While the operation of the auto tensioner in the contracting direction is locked, reverse torque is generated in the motor / generator, and when the transmission belt is loosened, the auto tensioner is operated in the tension direction, and the state is maintained. Then, in the internal combustion engine start control method for starting the internal combustion engine by generating a positive torque thereafter,
Detecting the normal rotation and the reverse rotation of the rotation shaft of the motor / generator based on the electrical angle position detected by the electrical angle position sensor that detects the electrical angle position of the rotation shaft of the motor / generator;
When it is detected based on the electrical angle position detected by the electrical angle position sensor that the rotation shaft of the motor / generator is reversely rotated due to the generation of reverse torque of the motor / generator, the crank of the internal combustion engine is controlled for engine operation timing control. Disable the detection signals of various crank sensors that detect the rotation state of the shaft,
When detecting the positive rotation of the motor / generator rotating shaft due to the generation of the positive torque of the motor / generator based on the electric angle position detected by the electric angle position sensor, the detection signals of the various crank sensors are validated. Then, the internal combustion engine is started and controlled by starting driving of the device whose timing is controlled based on the detection signal. A power transmission mechanism in which an endless transmission belt is stretched between pulleys of a crankshaft of an internal combustion engine, a rotation shaft of a motor / generator, and a rotation shaft of other auxiliary machinery is transmitted to a power transmission mechanism. And an auto tensioner that can be locked only in the direction of loosening the transmission belt.
While the operation of the auto tensioner in the contracting direction is locked, reverse torque is generated in the motor / generator, and when the transmission belt is loosened, the auto tensioner is operated in the tension direction, and the state is maintained. Then, in the internal combustion engine start control method for starting the internal combustion engine by generating a positive torque thereafter,
When a reverse rotation instruction signal for generating reverse torque is output to the motor / generator, the detection signals of various crank sensors for detecting the rotation state of the crankshaft of the internal combustion engine for engine operation timing control are invalidated,
When a positive rotation instruction signal for generating a positive torque of the motor / generator is output, the detection signals of the various crank sensors are validated after a lapse of a predetermined time from which it can be estimated that the crankshaft has started to positively rotate reliably. Then, the internal combustion engine is started and controlled by starting driving of the device whose timing is controlled based on the detection signal. A power transmission mechanism in which an endless transmission belt is stretched between pulleys of a crankshaft of an internal combustion engine, a rotation shaft of a motor / generator, and a rotation shaft of other auxiliary machinery is transmitted to a power transmission mechanism. And an auto tensioner that can be locked only in the direction of loosening the transmission belt.
While the operation of the auto tensioner in the contracting direction is locked, reverse torque is generated in the motor / generator, and when the transmission belt is loosened, the auto tensioner is operated in the tension direction, and the state is maintained. Then, in the internal combustion engine start control method for starting the internal combustion engine by generating a positive torque thereafter,
When a start command signal is output, various crank sensors for detecting the rotational state of the crankshaft of the internal combustion engine for engine operation timing control until a predetermined time elapses when it can be estimated that the crankshaft has started to rotate positively . Disable the detection signal,
The internal combustion engine is started by controlling the start of the device whose timing is controlled based on the detection signal by making the detection signals of the various crank sensors valid after the predetermined time has elapsed. Control method.

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