JP2014134151A - Engine-rotation-condition detection method and engine-rotation-condition detection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an engine-rotation-condition detection device highly accurately detecting a rotation condition of an engine in a vehicle equipped with an alternator.SOLUTION: An engine-rotation-condition detection device 100 for detecting a rotation of an engine in a vehicle equipped with an alternator 21 includes a phase terminal output acquisition unit 10 which acquires values of voltages at a P1 and a P2 terminals in the alternator 21, and an engine rotation condition detection unit 11 which detects a rotation condition of the engine on the basis of time sequence of the two voltages.

Description

  The present invention relates to an engine rotation state detection method and an engine rotation state detection device for detecting the rotation state of an engine in a vehicle equipped with an alternator.

  Conventionally, an engine speed control device that detects an engine speed based on a pulse signal taken out from a P terminal of an alternator is known (see Patent Document 1).

  This engine speed control device is used in place of the rotation speed sensor when a rotation speed sensor that outputs a pulse signal proportional to the rotation speed of the fuel injection camshaft linked to the crankshaft via a gear fails. Used to detect the engine speed.

JP 2005-105840 A

  However, the engine speed control device described in Patent Document 1 is used in an emergency evacuation instead of a malfunctioning speed sensor, and has a lower detection accuracy than the speed sensor, and operates normally. It is not used in place of a sensor.

  In view of the above-described points, an object of the present invention is to provide an engine rotation state detection method and an engine rotation state detection device that detect the rotation state of an engine in a vehicle equipped with an alternator with higher accuracy.

  In order to achieve the above-mentioned object, an engine rotation state detection method according to an embodiment of the present invention is an engine rotation state detection method for detecting rotation of an engine in a vehicle equipped with an alternator, and a plurality of phases in the alternator. A phase terminal output acquisition step of acquiring at least two phase terminal outputs of the terminals; and an engine rotation state detection step of detecting a rotation state of the engine based on the at least two phase terminal outputs.

  An engine rotation state detection device according to an embodiment of the present invention is an engine rotation state detection device that detects engine rotation in a vehicle equipped with an alternator, and includes at least two of a plurality of phase terminals in the alternator. A phase terminal output acquisition unit configured to acquire a phase terminal output; and an engine rotation state detection unit configured to detect a rotation state of the engine based on the at least two phase terminal outputs.

  By the means described above, the present invention can provide an engine rotation state detection method and an engine rotation state detection device that detect the rotation state of the engine in a vehicle equipped with an alternator with higher accuracy.

It is a block diagram which shows the structural example of the engine rotation state detection apparatus which concerns on the Example of this invention. It is a schematic circuit diagram of the regulator and alternator connected to the engine rotation state detection apparatus of FIG. It is a figure explaining the method of deriving the angular velocity of the output shaft of an engine based on a single phase terminal output. It is a figure explaining the method of deriving the angular velocity of the output shaft of an engine based on two phase terminal outputs. It is a figure explaining the method of deriving the rotation direction of the output shaft of an engine based on two phase terminal outputs. It is a flowchart which shows the flow of a starting control process. It is a figure which shows the time transition of the engine speed after a fuel cut is performed.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a functional block diagram illustrating a configuration example of an engine rotation state detection device 100 according to an embodiment of the present invention. FIG. 2 is a schematic circuit diagram of the regulator 20 connected to the engine rotation state detection device 100 of FIG. 1 and the alternator 21 connected to the regulator 20.

  The regulator 20 is a device that adjusts the output voltage of the alternator 21 to a desired level. In this embodiment, the regulator 20 controls the field current by turning on / off the transistor 20T1 connected to the rotor coil (field coil) 21F via the F terminal of the alternator 21 with the Zener diode 20Z and the transistor 20T2. The output voltage of the alternator 21 is adjusted.

  The alternator 21 is a power generation device driven by an engine, and the number of poles, the number of phases, and the rotation speed ratio with respect to the engine can be arbitrarily set. In this embodiment, it is a three-phase 8-pole pair (16-pole) alternator, and is connected to the output shaft of the engine via a belt with a pulley ratio of 2.5.

  In the present embodiment, the alternator 21 has a G terminal, an F terminal, a P1 terminal, a P2 terminal, and a B terminal. The G terminal is a terminal connected to the ground point, and the F terminal is a terminal connected to the field coil 21F. The P1 terminal is a terminal connected to the U-phase coil 21U of the Y-connected stator coil, and the P2 terminal is a terminal connected to the V-phase coil 21V of the Y-connected stator coil. The B terminal is an output terminal and can be connected to a battery, various electric loads, and the like. The alternator 21 may include a P3 terminal (not shown) connected to the W-phase coil 21W among the Y-connected stator coils.

  In the present embodiment, the regulator 20 includes the first voltage sensor 2 and the second voltage sensor 3. The first voltage sensor 2 is connected to the P1 terminal of the alternator 21 and detects the voltage at the P1 terminal. The second voltage sensor 3 is connected to the P2 terminal of the alternator 21 and detects the voltage at the P2 terminal. The regulator 20 generates an output signal based on the detection results of the first voltage sensor 2 and the second voltage sensor 3, and generates the output signal through a network such as LIN (Local Interconnect Network), CAN (Control Area Network), etc. The output signal is output to the engine rotation state detection device 100.

  The engine rotation state detection device 100 is an in-vehicle device that detects the rotation state of the engine based on outputs of a plurality of phase terminals in the alternator 21. In the present embodiment, the engine rotation state detection device 100 detects the rotation state of the output shaft of the engine based on the output of the P1 terminal and the output of the P2 terminal of the alternator 21. Specifically, the engine rotation state detection device 100 receives the output signal generated by the regulator 20 based on the outputs of the P1 terminal and the P2 terminal, and the rotation state of the output shaft of the engine based on the received output signal. Is detected. In the present embodiment, the engine rotation state detection device 100 outputs information about the detected rotation state (for example, the number of rotations per unit time, the angular velocity, the rotation direction, and the like) to the starter 4.

  The starting device 4 is a device that starts a driving source of the vehicle. In the present embodiment, the starter 4 is a starter motor for starting the engine, and engages the ring gear coupled to the output shaft of the engine by jumping the pinion gear and rotationally driving the pinion gear. Start the engine. In this embodiment, the starter 4 is also used to restart engine rotation when the engine rotation is about to stop (when the engine to be stopped is still rotating at a low speed). It is done. Hereinafter, such control for restarting the engine during inertial rotation is referred to as “change of mind control”.

  Specifically, the starter 4 determines the timing at which the pinion gear jumps into the ring gear based on the information about the rotation state received from the engine rotation state detection device 100 in the change of mind control. More specifically, the starter 4 is configured to synchronize the pinion gear rotation speed with the engine rotation speed when the engine rotation speed is equal to or lower than a predetermined rotation speed and the engine is rotating forward. Engage the gear by jumping into the ring gear.

  In this way, in this embodiment, the engine rotation state detection device 100 is based on the output of the P1 terminal and the output of the P2 terminal of the alternator 21 so that the starter 4 can restart the stopped engine. Detects the rotation state of the output shaft.

  The engine rotation state detection device 100 has a control device 1. In this embodiment, the control device 1 is a computer having a CPU, RAM, ROM, input / output interface, and the like. And the control apparatus 1 reads the program corresponding to various function elements, such as the phase terminal output acquisition part 10 and the engine rotation state detection part 11, from ROM or RAM, and makes CPU perform the process corresponding to various function elements. Specifically, the control device 1 receives an output signal from the regulator 20 and executes a calculation corresponding to the phase terminal output acquisition unit 10 and the engine rotation state detection unit 11, and based on the calculation result, the starter 4 and the like. To control.

  The phase terminal output acquisition unit 10 is a functional element that acquires the output of the phase terminal of the alternator 21. In the present embodiment, the phase terminal output acquisition unit 10 acquires the output signal generated by the first voltage sensor 2 in the regulator 20 based on the voltage of the P1 terminal of the alternator 21 as the output of the U-phase terminal of the alternator 21. Further, the phase terminal output acquisition unit 10 acquires the output signal generated by the second voltage sensor 3 in the regulator 20 based on the voltage at the P2 terminal of the alternator 21 as the output of the V-phase terminal of the alternator 21.

  The engine rotation state detection unit 11 is a functional element that detects the rotation state of the engine. In the present embodiment, the engine rotation state detection unit 11 detects the rotation state of the rotation shaft of the alternator 21 and thus the rotation state of the output shaft of the engine based on the output of the phase terminal acquired by the phase terminal output acquisition unit 10. To do. The rotation state includes the number of rotations per unit time, angular velocity, rotation direction, and the like. The rotation state of the output shaft of the engine is derived based on the rotation state of the rotation shaft of the alternator 21 and the rotation speed ratio of the alternator 21 to the engine (in this embodiment, the pulley ratio). Details of detection of the rotation state will be described later.

  Here, a process in which the engine rotation state detection device 100 detects the rotation state of the engine (hereinafter referred to as “engine rotation detection process”) will be described with reference to FIGS. 3 to 5.

  FIG. 3 illustrates a method for deriving the angular velocity of the engine output shaft based on a single phase terminal output. 3 shows the time transition of the voltage at the P1 terminal, the horizontal axis represents the elapsed time, and the vertical axis represents the phase terminal voltage. The middle part of FIG. 3 shows the temporal transition of the output signal output from the first voltage sensor 2, the horizontal axis represents the elapsed time, and the vertical axis represents the magnitude of the output signal (voltage signal). The lower part of FIG. 3 shows the temporal transition of the rotation angle of the alternator 21 detected by the engine rotation state detection unit 11, the horizontal axis represents the elapsed time, and the vertical axis represents the rotation angle. Note that the time axis in each of the upper, middle, and lower stages in FIG. 3 is common.

  As shown in the upper part of FIG. 3, the P1 terminal of the alternator 21 having an 8-pole pair of pole cores includes one convex portion every 45 degrees of mechanical angle, that is, every time the rotation axis of the alternator 21 rotates 45 degrees. Output voltage waveform.

The first voltage sensor 2 outputs the pulse wave shown in the middle part of FIG. 3 as an output signal to the engine rotation state detection device 100 in accordance with the voltage at the P1 terminal that forms the voltage waveform shown in the upper part of FIG. Specifically, the first voltage sensor 2 outputs the output voltage HI as an output signal when the voltage at the P1 terminal is equal to or higher than the predetermined voltage _VTH , and the output voltage when the voltage at the P1 terminal is _lower than the predetermined voltage _VTH. LO is output as an output signal. In this embodiment, the first voltage sensor 2, the time u1, u3, u5, when the voltage of the terminal P1 becomes equal to or higher than the predetermined voltage _{V TH} at., And the level of the output signal and the output voltage HI, time u2, u4 , u6, the voltage of the terminal P1 is less than the predetermined voltage _{V TH} at ..., and the level of the output signal and the output voltage LO. In this way, the first voltage sensor 2 outputs one pulse for every 45 degrees of mechanical angle. That is, the first voltage sensor 2 outputs eight pulses (eight on signals and eight off signals) per alternator rotation. Further, the first voltage sensor 2 outputs 20 pulses (20 on signals and 20 off signals) per one rotation of the engine when the pulley ratio is 2.5. The engine rotation state detection device 100 may generate an output signal instead of the first voltage sensor 2. In this case, the first voltage sensor 2 outputs the voltage of the P1 terminal to the engine rotation state detection device 100 as it is.

Further, as shown in the lower part of FIG. 3, the engine rotation state detection unit 11 detects the rotation angle of the alternator 21 with, for example, time t0 as a starting point. Specifically, the engine rotational state detecting unit 11, by integrating a predetermined mechanical angle theta _P when the first pulse at time u1 is first pulse at time u2 turned on is turned off The rotation angle θ _u2 (= 0 + θ _P = θ _P ) is detected. Note that the predetermined mechanical angle theta _P, is a value determined depending on the shape of the pole core. Thereafter, the engine rotation state detection unit 11 adds the mechanical angle 45 degrees when the second pulse is turned on at time u3, and obtains the rotation angle θ _u3 (= θ _u2 + 45 ° = θ _P + 45 °). To detect. Thereafter, the engine rotation state detection unit 11 integrates the mechanical angle θ _P when the second pulse is turned off at time u4, and rotates the rotation angle θ _u4 (= θ _u3 + θ _P = 2 × θ _P + 45 °). ) Is detected. Further, the engine rotational state detecting unit 11 integrates the mechanical angle of 45 degrees when the third pulse at the time u5 is turned on by the rotation angle _{θ u5 (= θ u4 + 45} ° = 2 × θ P + 90 ° ) Is detected. Thereafter, similarly, the engine rotation state detection unit 11 integrates the mechanical angle θ _P every time the pulse is turned off, and adds 45 mechanical angles each time the pulse is turned on to detect the rotation angle of the alternator 21. To do.

  Further, the engine rotation state detection unit 11 derives the angular velocity by dividing the detected rotation angle of the alternator 21 by the elapsed time, and divides the angular velocity by a mechanical angle of 360 degrees (an angle corresponding to one rotation of the alternator 21). Can derive the number of revolutions per unit time. Furthermore, the engine rotation state detection unit 11 can derive the rotation angle, angular velocity, and rotation speed of the engine by dividing the rotation angle, angular velocity, and rotation speed of the alternator 21 by the pulley ratio.

  Next, a method for deriving the angular velocity of the engine output shaft based on the two phase terminal outputs will be described with reference to FIG. The upper part of FIG. 4 is a diagram corresponding to the upper part of FIG. 3, and the time transition of the voltage at the P1 terminal is indicated by a solid line and the time transition of the voltage at the P2 terminal is indicated by a broken line. The middle part of FIG. 4 is a diagram corresponding to the middle part of FIG. 3. The temporal transition of the output signal output from the first voltage sensor 2 is indicated by a solid line, and the temporal transition of the output signal output from the second voltage sensor 3 is shown. Is indicated by a broken line. The lower part of FIG. 4 is a diagram corresponding to the lower part of FIG. 3, and shows the temporal transition of the rotation angle of the alternator 21 detected by the engine rotation state detection unit 11 based on the two phase terminal outputs with a solid line. For comparison, the lower part of FIG. 4 corresponds to the temporal transition of the rotation angle of the alternator 21 detected by the engine rotational state detection unit 11 based on a single phase terminal output (corresponding to the temporal transition of the lower part of FIG. 3). ) Is indicated by a one-dot chain line.

  As indicated by the solid line in the upper part of FIG. 4, the P1 terminal of the alternator 21 having an 8-pole pair of pole cores outputs a voltage waveform including one convex portion for every 45 degrees of mechanical angle. Similarly, as indicated by the broken line in the upper part of FIG. 4, the P2 terminal includes one convex portion for every 45 degrees of mechanical angle with a delay of 120 degrees in electrical angle, that is, 15 degrees in mechanical angle with respect to the voltage waveform of the P1 terminal. Output voltage waveform.

  The first voltage sensor 2 outputs the pulse wave indicated by the solid line in the middle of FIG. 4 as an output signal to the engine rotation state detection device 100 in response to the voltage at the P1 terminal forming the voltage waveform indicated by the solid line in the upper part of FIG. To do. Similarly, the second voltage sensor 3 outputs a pulse wave indicated by the broken line in the middle of FIG. 4 to the engine rotation state detection device 100 as an output signal in accordance with the voltage at the P2 terminal forming the voltage waveform indicated by the broken line in the upper part of FIG. Output.

In this embodiment, the first voltage sensor 2, the time u1, u3, u5, when the voltage of the terminal P1 becomes equal to or higher than the predetermined voltage _{V TH} at., And the level of the output signal and the output voltage HI, time u2, u4 , u6, the voltage of the terminal P1 is less than the predetermined voltage _{V TH} at ..., and the level of the output signal and the output voltage LO. The second voltage sensor 3, the time v1, v3, v5, the voltage of the terminal P2 becomes equal to or higher than the predetermined voltage _{V TH} at., And the level of the output signal and the output voltage HI, time v2, v4, v6, When the voltage at the P2 terminal becomes less than the predetermined voltage _VTH , the level of the output signal is set to the output voltage LO.

  Thus, the 1st voltage sensor 2 and the 2nd voltage sensor 3 output one pulse for every 45 degrees of mechanical angles. The engine rotation state detection device 100 may generate an output signal instead of the first voltage sensor 2 and the second voltage sensor 3. In this case, the first voltage sensor 2 and the second voltage sensor 3 output the voltage at the P1 terminal and the voltage at the P2 terminal to the engine rotation state detection device 100 as they are.

Further, as shown in the lower part of FIG. 4, the engine rotation state detection unit 11 detects the rotation angle of the alternator 21 with time t0 as a starting point, for example. Specifically, the engine rotation state detection unit 11 turns on a pulse relating to the first P1 terminal (hereinafter referred to as “P1 pulse”) at time u1 and turns on a pulse relating to the first P2 terminal at time v1 ( Hereinafter, when “P2 pulse” is turned on, the mechanical angle of 15 degrees is integrated to detect the rotation angle θ _v2 (= 0 + 15 °). Thereafter, the engine rotation state detection unit 11 accumulates a predetermined mechanical angle θ _P1 when the first P1 pulse is turned off at time u2, and rotates the rotation angle θ _u2 (= 15 ° + θ _P1 = θ _P ). Is detected. The predetermined mechanical angle θ _P1 is, for example, a value obtained by subtracting an electrical angle of 120 degrees, that is, a mechanical angle of 15 degrees from a predetermined mechanical angle θ _P determined according to the shape of the pole core. Thereafter, the engine rotation state detection unit 11 adds the mechanical angle of 15 degrees when the first P2 pulse is turned off at time v2, and detects the rotation angle θ _v2 (= θ _P + 15 °). Thereafter, the engine rotation state detection unit 11 integrates the mechanical angle of 30 degrees (= 45 ° -15 °) when the second P1 pulse is turned on at time u3, and the rotation angle θ _u3 (= θ _P + 15 ° + 30 ° = θ _P + 45 °) is detected. Thereafter, the engine rotation state detection unit 11 adds the mechanical angle of 15 degrees when the second P2 pulse is turned on at time v3, and rotates the rotation angle θ _v3 (= θ _P + 45 ° + 15 ° = θ _P + 60 °). ) Is detected. Thereafter, similarly, the engine rotation state detection unit 11 accumulates a mechanical angle of 30 degrees every time the P1 pulse is turned on, accumulates a mechanical angle of 15 degrees every time the P2 pulse is turned on, and turns off the P1 pulse. Each time, the mechanical angle θ _P1 is integrated, and every time the P2 pulse is turned off, the mechanical angle 15 degrees is integrated to detect the rotation angle of the alternator 21.

  Further, the engine rotation state detection unit 11 derives the angular velocity by dividing the detected rotation angle of the alternator 21 by the elapsed time, and divides the angular velocity by a mechanical angle of 360 degrees (an angle corresponding to one rotation of the alternator 21). Can derive the number of revolutions per unit time. Furthermore, the engine rotation state detection unit 11 can derive the rotation angle, angular velocity, and rotation speed of the engine by dividing the rotation angle, angular velocity, and rotation speed of the alternator 21 by the pulley ratio.

Further, the rotation angle of the alternator 21 detected based on the two phase terminal outputs indicated by the solid line in the lower part of FIG. 4 is based on the rotation angle of the alternator 21 detected based on the single phase terminal output indicated by the broken line in the lower part of FIG. Are also detected with high resolution. Specifically, the rotation angle detected at time t1 is the same rotation angle θ _u2 when based on two phase terminal outputs and when based on a single phase terminal output. On the other hand, the rotation angle detected at time t2 becomes the rotation angle θ _v3 when based on the two phase terminal outputs, and becomes the rotation angle θ _u3 when based on the single phase terminal output. When based on two phase terminal outputs, the value of the rotation angle is updated at times v1, u2, v2, u3, v3,..., Whereas when based on a single phase terminal output, time v1 , V2, v3,..., Because the value of the rotation angle is not updated.

  Next, a method of deriving the rotation direction of the engine output shaft based on the two phase terminal outputs will be described with reference to FIG. The upper part of FIG. 5 is a diagram corresponding to the upper part of FIG. 4, and shows the temporal transition of the voltage at the P1 terminal with a solid line and the temporal transition of the voltage at the P2 terminal with a broken line. The middle part of FIG. 5 is a diagram corresponding to the middle part of FIG. 4. The temporal transition of the output signal output from the first voltage sensor 2 is indicated by a solid line, and the temporal transition of the output signal output from the second voltage sensor 3 is shown. Is indicated by a broken line. The lower part of FIG. 5 is a diagram corresponding to the lower part of FIG. 4, and shows the temporal transition of the rotation angle of the alternator 21 detected by the engine rotation state detection unit 11 based on the two phase terminal outputs with a solid line.

  The time transition of the phase terminal voltage in the upper part of FIG. 5 is different from the time transition of the phase terminal voltage shown in the upper part of FIG. 4 in that the rotation direction of the alternator 21 is reversed between the time v2 and the time v3r.

  When the alternator 21 is rotating forward, the engine rotation state detection unit 11 outputs output signals in the order of P1 pulse on, P2 pulse on, P1 pulse off, P2 pulse off, P1 pulse on,... To detect. On the other hand, when the alternator 21 rotates in reverse, the engine rotation state detection unit 11 detects output signals in the order of P2 pulse on, P1 pulse on, P2 pulse off, P1 pulse off, P2 pulse on,.

  Therefore, as shown in the middle part of FIG. 5, for example, the engine rotation state detection unit 11 detects the P2 pulse on at time v3r after detecting the P2 pulse off at time v2 and before the P1 pulse is turned on. It is detected that the rotation direction of is reversed.

  As described above, the engine rotation state detection unit 11 detects whether the rotation direction of the alternator 21 is normal rotation or reverse rotation based on the turn-on / off order of the P1 pulse and the P2 pulse.

  When the engine rotation state detection unit 11 detects that the rotation direction of the alternator 21 has been reversed, the engine rotation state detection unit 11 resets the integration of the rotation angle and inverts the sign of the rotation angle to be integrated. Note that a positive sign indicates forward rotation, and a negative sign indicates reverse rotation.

Specifically, as shown in the lower part of FIG. 5, for example, when the engine rotation state detection unit 11 detects that the rotation direction of the alternator 21 is reversed at time v3r, the rotation angle integration unit 11 resets the rotation angle integration. Thereafter, when the P1 pulse is turned on at time u3r, the engine rotation state detection unit 11 integrates the mechanical angle −15 degrees to detect the rotation angle θ _u3r (= 0-15 °). Thereafter, the engine rotation state detection unit 11 accumulates a predetermined mechanical angle −θ _P1 when the P2 pulse is turned off at time v4r, and the rotation angle θ _v4r (= −15 ° −θ _P1 = −θ _P ). Is detected. Thereafter, the engine rotation state detection unit 11 adds the mechanical angle −15 degrees when the P1 pulse is turned off at time u4r, and detects the rotation angle θ _u4r (= −θ _P −15 °). Thereafter, the engine rotation state detection unit 11 accumulates the mechanical angle −30 degrees (= −45 ° + 15 °) when the P2 pulse is turned on at time v5r, and rotates the rotation angle θ _v5r (= −θ _P −15). (° -30 ° = −θ _P −45 °) is detected. Thereafter, the engine rotation state detection unit 11 adds the mechanical angle −15 degrees when the P1 pulse is turned on at time u5r, and adds the rotation angle θ _u5r (= −θ _P −45 ° −15 ° = −θ _P −60 °) is detected. Thereafter, similarly, the engine rotation state detection unit 11 accumulates a mechanical angle of −30 degrees every time the P2 pulse is turned on, accumulates a mechanical angle of −15 degrees every time the P1 pulse is turned on, and the P2 pulse is A predetermined mechanical angle −θ _P1 is integrated every time the switch is turned off, and a mechanical angle −15 degrees is integrated every time the P1 pulse is turned off to detect the rotation angle of the alternator 21.

  Further, the engine rotation state detection unit 11 derives the angular velocity by dividing the detected rotation angle of the alternator 21 by the elapsed time, and divides the angular velocity by a mechanical angle of 360 degrees (an angle corresponding to one rotation of the alternator 21). Can derive the number of revolutions per unit time. Furthermore, the engine rotation state detection unit 11 can derive the rotation angle, angular velocity, and rotation speed of the engine by dividing the rotation angle, angular velocity, and rotation speed of the alternator 21 by the pulley ratio.

  In this way, the engine rotation state detection device 100 detects the rotation state of the rotation shaft of the alternator 21, and thus the rotation state of the output shaft of the engine.

  Next, referring to FIG. 6, the control device 1 of the engine rotation state detection device 100 controls the starter 4 based on the detected rotation state of the engine (hereinafter referred to as “starting control processing”). Will be described. FIG. 6 is a flowchart showing the flow of the start control process. For example, the control device 1 performs the fuel cut by the idling stop function, that is, the engine is automatically stopped at a predetermined cycle until the engine is stopped. This start control process is repeatedly executed.

  Initially, the phase terminal output acquisition part 10 of the control apparatus 1 acquires the output of the several phase terminal in the alternator 21 (step S1). Specifically, the phase terminal output acquisition unit 10 acquires output signals of the first voltage sensor 2 and the second voltage sensor 3 in the regulator 20. The output signal is a voltage signal composed of two voltage levels of the output voltage HI or the output voltage LO, which represents the temporal transition of the voltage at the P1 terminal and the P2 terminal of the alternator 21 (see the middle stage in FIG. 4). .

  Thereafter, the engine rotation state detection unit 11 of the control device 1 detects the rotation state of the engine (step S2). Specifically, the engine rotation state detection unit 11 integrates the rotation angle of the rotation shaft of the alternator 21 every time the voltage signal acquired by the phase terminal output acquisition unit 10 changes (see the lower part of FIG. 4). Then, the engine rotation state detection unit 11 calculates the engine rotation speed per unit time based on the rotation angle of the rotation shaft of the alternator 21 and the pulley ratio accumulated over a predetermined time. Further, the engine rotation state detection unit 11 detects whether the rotation direction of the alternator 21 is normal rotation or reverse rotation based on the order of appearance of the P1 pulse and the P2 pulse. The engine rotation state detection unit 11 detects whether the rotation direction of the output shaft of the engine that rotates together with the rotation shaft of the alternator 21 is normal rotation or reverse rotation (see FIG. 5).

  Thereafter, the engine rotation state detection unit 11 transmits the detected rotation state of the engine to the starter 4 (step S3). This is because the starter 4 can synchronize the rotation speed of the pinion gear with the engine speed before the pinion gear of the starter 4 and the ring gear of the engine are engaged.

  After that, the control device 1 determines whether or not a restart command for restarting the engine is received from another ECU (Electric Control Unit) that executes the idling stop function (step). S4). The restart command is output to the control device 1 when the driver's intention to start is confirmed, such as when the accelerator pedal is depressed.

  When it is determined that a restart command has been received (YES in step S4), the control device 1 determines whether the detected engine speed is within a predetermined speed range and whether the engine rotation direction is normal rotation. (Step S5). The “predetermined rotational speed range” is a rotational speed range in which the engine cannot be autonomously started, and is, for example, 500 [rpm] or less. Further, the “predetermined rotational speed range” may be 200 [rpm] or less, or 150 [rpm] or less. “Autonomous engine start” means, for example, that the engine is restarted only by injecting fuel without using the starter 4 or by injecting fuel and igniting the spark plug.

  When it is determined that the engine rotational speed is within the predetermined rotational speed range and the rotational direction of the engine is normal rotation (YES in step S5), the control device 1 outputs a jump command to the starting device 4. (Step S6). Upon receiving the jump command, the starting device 4 jumps into the ring gear the pinion gear whose rotational speed is already synchronized with the engine and restarts the engine. When the rotation speed of the pinion gear is not yet synchronized with the rotation speed of the engine, the starter 4 may delay the jump into the ring gear until the rotation is synchronized.

  On the other hand, when it is determined that the restart command has not been received (NO in step S4), or when it is determined that the engine speed is out of the predetermined speed range, or when the engine rotation direction is reverse rotation. If it is determined that there is (NO in step S5), the control device 1 ends the current start control process without outputting the jump command to the start device 4.

  In this way, the engine rotation state detection device 100 can detect the rotational speed of the engine during inertial rotation with high accuracy and can quickly detect the rotational direction of the engine. Therefore, the engine rotation state detection device 100 can restart the engine by jumping the pinion gear of the starter 4 into the ring gear before the engine stops without damaging the starter 4 and the ring gear. it can. Since the conventional starter prohibits restart until the engine is completely stopped, the engine does not restart even when the driver depresses the accelerator pedal, and it is operated during change-of-mind control. The person had a feeling of shakyness. However, since the engine rotation state detection device 100 can restart the engine early as described above, it can reduce or eliminate the feeling of the driver's feeling at the time of change-of-mind control.

  Next, the timing at which the engine rotation state detection device 100 outputs a jump command to the starter 4 will be described with reference to FIG. FIG. 7 is a diagram showing a temporal transition of the engine speed after the fuel cut is executed, in which the horizontal axis represents the elapsed time and the vertical axis represents the engine speed.

  As shown in FIG. 7, the engine continues to rotate for a while after the fuel supply is stopped, and is in an autonomously startable state if the engine speed is higher than a certain level. That is, if the supply of fuel is resumed, the operation can be resumed without relying on the starter 4. Therefore, in this embodiment, the engine rotation state detection device 100 determines that the engine is in an autonomously startable state if the engine rotation number is equal to or higher than a predetermined rotation number R1 (for example, 500 [rpm]). Even when the operation is restarted, the starter 4 is not used. On the other hand, when the engine speed falls below the predetermined speed R1, the engine enters an autonomous start impossible state, and the operation cannot be resumed unless the starter 4 is used. Therefore, the engine rotation state detection device 100 outputs a jump command to the starter 4 and restarts the engine when the engine is in an autonomous start disabled state and the engine rotation state satisfies a predetermined condition. Let

  The hatched hatching arranged on the horizontal axis in FIG. 7 represents a case where the engine is in an autonomous start impossible state and the engine rotation state does not satisfy a predetermined condition, that is, a restart is prohibited. On the other hand, dot hatching represents a case where the engine is in an autonomous start-disabled state and the engine rotation state satisfies a predetermined condition, that is, a restart is permitted.

  Specifically, during the period from time t11 to t12, the engine speed is equal to or higher than a predetermined speed R2 (for example, 200 [rpm]), and therefore restart by the starter 4 is prohibited. This is because the rotational speed of the engine is too high and the difference between the rotational speed of the pinion gear and the rotational speed of the ring gear is too large to cause the pinion gear of the starting device 4 to jump into the ring gear of the engine. Further, when the pinion gear is jumped into the ring gear, an excessive external torque is applied to the motor of the starter 4, which may damage the pinion gear, the internal parts of the starter 4, the ring gear, and the like. .

  Further, at the time t13 to t14 and the time t15 to t16, the engine piston swings without being able to get over the compression stroke, and the engine rotation direction is reverse. Restart by 4 is prohibited. In this case as well, when the pinion gear is jumped into the ring gear, an excessive external torque is applied to the motor of the starter 4, and the pinion gear, the internal parts of the starter 4, the ring gear, etc. may be damaged. Because there is.

  On the other hand, at the time t12 to t13, the time t14 to t15, and the time after time t16, the engine speed is less than the predetermined speed R2, and the engine rotation direction is normal. Alternatively, since the engine speed is almost zero, restart by the starter 4 is permitted. Even when the pinion gear jumps into the ring gear, an excessive external torque is not applied to the motor of the starter 4, and there is no possibility of damaging the pinion gear, the internal parts of the starter 4, the ring gear, or the like. Because.

  As described above, the engine rotation state detection device 100 detects the engine rotation state with high accuracy based on the temporal transition of the two phase terminal voltages of the alternator 21, so that the engine rotation state is detected at an earlier stage. The engine can be restarted by the starter 4. As a result, it is possible to reduce or eliminate the feeling that the driver feels during the change of mind control.

  The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the present invention. Can be added.

  For example, in the above-described embodiment, the engine rotation state detection device 100 detects the rotation state of the alternator 21 based on the voltage at the P1 terminal and the voltage at the P2 terminal. However, the present invention is not limited to this. The engine rotation state detection device 100 may detect the rotation state of the alternator 21 based on, for example, the voltage at the P1 terminal, the voltage at the P2 terminal, and the voltage at the P3 terminal, and the voltage at the P1 terminal and the voltage at the P3 terminal , The rotational state of the alternator 21 may be detected, or the rotational state of the alternator 21 may be detected based on the voltage at the P2 terminal and the voltage at the P3 terminal.

  In the above-described embodiment, the alternator 21 functions as a generator, but may function as a starter (electric motor). In this case, the starting device 4 may be omitted.

  In the above-described embodiment, the engine rotation state detection apparatus 100 detects the rotation state of the engine until the engine is stopped after the fuel cut by the idling stop function is executed. However, the present invention is not limited to this. The engine rotation state detection device 100 may detect the rotation state of the engine during engine operation. In this case, the rotation speed sensor that detects the rotation speed of the output shaft of the engine may be omitted.

  In the above-described embodiment, the control device 1 that generates the output signal instead of the first voltage sensor 2, the second voltage sensor 3, or the second voltage sensor 3 converts the phase terminal voltage into two stages of the output voltage HI and the output voltage LO. Although expressed by a value, it may be expressed by a value of three or more levels. For example, if the phase transition of the phase terminal voltage is expressed not as a pulse wave but as a sine wave, a triangular wave, etc., and 180 degrees of the sine wave are divided into an increase step voltage and a decrease step voltage, the phase terminal voltage is increased step voltage and decrease step voltage. , And a three-stage value of the output voltage LO. Thereby, the engine rotation state detection apparatus 100 can increase the detection accuracy of the rotation state of the alternator 21, and can increase the detection accuracy of the rotation state of the engine.

  DESCRIPTION OF SYMBOLS 1 ... Control apparatus 2 ... 1st voltage sensor 3 ... 2nd voltage sensor 4 ... Starting device 10 ... Phase terminal output acquisition part 11 ... Engine rotation state detection part 20 ... Regulator 20T1, 20T2 ... Transistor 20Z ... Zener diode 21 ... Alternator 21U ... U phase coil 21V ... V phase coil 21W ... W phase coil 21F ... Rotor coil 100 ... Engine rotation state detection device

Claims (5)

An engine rotation state detection method for detecting engine rotation in a vehicle equipped with an alternator,
A phase terminal output acquisition step of acquiring at least two phase terminal outputs of the plurality of phase terminals in the alternator;
An engine rotation state detection step for detecting a rotation state of the engine based on the at least two phase terminal outputs;
An engine rotation state detection method comprising: In the engine rotation state detection step, the rotation direction of the engine is detected based on a detection order of predetermined states in the at least two phase terminal outputs.
The engine rotation state detection method according to claim 1. In the engine rotation state detection step, every time a predetermined state is detected in the at least two phase terminal outputs, a predetermined rotation angle is integrated to detect the rotation state of the engine.
The engine rotation state detection method according to claim 1 or 2. The phase terminal output is the voltage at the phase terminal,
The predetermined state includes a state where the voltage is equal to or higher than the predetermined voltage and a state where the voltage is lower than the predetermined voltage.
The engine rotation state detection method according to any one of claims 1 to 3. An engine rotation state detection device for detecting engine rotation in a vehicle equipped with an alternator,
A phase terminal output acquisition unit for acquiring at least two phase terminal outputs of the plurality of phase terminals in the alternator;
An engine rotation state detector for detecting a rotation state of the engine based on the at least two phase terminal outputs;
An engine rotation state detection device having:

Images