JP2014139419A - Engine starting device, and engine starting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To quickly and silently restart an engine during inertia rotation in an engine automatic stop/start system, while suppressing impact shock in engagement of a pinion gear and a ring gear even under large rotational fluctuation of the engine.SOLUTION: A controller (10) executes determination of engagement permission and determination of engagement prohibition on the basis of an engine rotating speed, while considering switching between permission and prohibition of engagement of a starter during reduction of engine rotation, and processing cycle, and a result of the determination of the engagement prohibition has priority when the result of the determination of engagement permission is permission, and the result of the determination of the engagement prohibition is prohibition.

Description

  The present invention relates to an engine starter and an engine start method for an engine automatic stop start system that stops fuel supply to an engine when a predetermined engine stop condition is satisfied, and then restarts the engine when a restart condition is satisfied. It is about.

  2. Description of the Related Art Conventionally, an engine automatic stop / start system has been developed that stops fuel supply to an engine when a predetermined engine stop condition is satisfied for the purpose of improving the fuel consumption of an automobile and reducing the environmental load. However, it takes time until the engine rotation is completely stopped by the frictional force, and the conventional engine automatic stop / start system cannot be restarted during this period.

  Therefore, as a method for solving this problem, the rotational speed of the internal combustion engine is below the maximum rotational speed within the predetermined range and above the minimum rotational speed, and the rotational direction corresponds to the forward rotational direction of the crankshaft. In this case, there is a method in which a starter pinion is meshed with a ring gear (see, for example, Patent Document 1).

  In addition, the engine automatic stop / start control device includes a starter that can individually operate a motor that rotationally drives the pinion and an actuator that meshes the pinion with a ring gear connected to the crankshaft of the engine. When an engine restart request is generated in the engine rotation speed range where the engine rotation speed decreases, the pinion is engaged with the ring gear by the actuator, or after the engagement. In some cases, a pinion is rotated by a motor in the middle, cranking by a starter is started, and the engine is restarted (for example, see Patent Document 2).

  Further, in the engine starter, when the restart condition is established during the engine rotation descent period, when the movement of the pinion to the ring gear side by the meshing means is started, the engine rotation speed predicted by the rotation prediction means is set. Based on whether or not the transition to the meshing state of the pinion and the ring gear occurs during the reversal of the output shaft, and based on the determination result, at least the start of movement of the pinion and the rotation of the motor by the meshing means An engine starter that controls any timing is known (see, for example, Patent Document 3).

JP 2007-107527 A JP 2011-099455 A JP 2012-031819 A

However, the prior art has the following problems.
In Patent Document 1, it is possible to realize engine restart earlier than when the engine is stopped until the engine is completely stopped, and then the pinion gear and the ring gear are engaged and restarted. However, in general, the engine repeats forward rotation and reverse rotation around 0 rpm during inertial rotation, but meshing during reverse rotation of the engine has not been considered.

  Further, there is a problem that the meshing is not performed when the engine does not fall within a predetermined range of forward rotation after the engine rotates in reverse. Furthermore, no consideration was given to the calculation cycle of the engine speed.

  Also in Patent Document 2, it is possible to realize engine restart earlier than waiting for a complete stop of the engine. However, this patent document 2 does not mention anything about the meshing during reverse rotation. Further, there is a description that the pinion gear is meshed before the reverse rotation by the actuator. However, even when a restart request is not generated when the engine is stopped, the pinion gear and the ring gear are engaged each time, and therefore a meshing sound is generated regardless of the operation of the driver, which gives the driver a sense of incongruity. There was a risk of it.

  In Patent Document 3, the reverse rotation peak value ΔNE is calculated, and if the reverse rotation peak value ΔNE is equal to or less than the threshold value, it is considered that the influence of the excessive increase in power consumption of the motor is relatively small. A configuration is described in which meshing is permitted even inside. However, there is no description regarding the switching between permission and prohibition of engagement when the engine rotational fluctuation is large, and there is no description regarding the processing cycle. Therefore, when the engine rotational fluctuation is large, there is a possibility that the meshing may be permitted regardless of the engine speed at which the meshing should be prohibited.

  The present invention has been made to solve the above-described problems. Even when the rotational fluctuation of the engine is large, the engine automatic operation is suppressed while suppressing the impact at the time of meshing between the pinion gear and the ring gear. It is an object of the present invention to provide an engine starter and an engine start method that can quickly and silently perform restart during inertial rotation of an engine in a stop / start system.

  An engine starter according to the present invention includes a starter for starting an engine, an engine rotation speed calculation unit that calculates an engine rotation speed for each predetermined processing cycle, and at least a predetermined processing cycle by an engine rotation speed calculation unit. It is determined at every predetermined processing cycle whether or not the engine rotation speed thus obtained is equal to or less than the engagement permission rotation speed. If it is equal to or less than the engagement permission rotation speed, the operation of the starter is permitted with the determination result being permitted. Predetermining whether or not the engine speed calculated at least every predetermined processing cycle by the permission determining unit and the engine speed calculating unit is equal to or lower than the meshing prohibition rotational speed defined as a value smaller than the meshing permitted rotational speed If the rotation speed is below the meshing prohibition rotation speed, the determination result is prohibited and the starter operates. A prohibition determination unit that prohibits, and a starter control unit that determines whether or not to operate the starter for each predetermined processing cycle based on the determination results of the permission determination unit and the prohibition determination unit. When the determination result by the permission determination unit is permitted and the determination result by the prohibition determination unit is prohibited in the current processing cycle for each predetermined processing cycle, the determination result by the prohibition determination unit is given priority, and the starter The operation is prohibited.

  An engine start method according to the present invention is an engine start method executed by a controller in an engine starter having a starter for starting an engine, and calculates an engine rotation speed every predetermined processing cycle. It is determined at every predetermined processing cycle whether the engine speed calculated at every predetermined processing cycle in the speed calculating step and at least the engine rotational speed calculating step is below the meshing allowable rotational speed, and the meshing allowable rotational speed. In the case of the following, the determination result is permitted, the permission determination step for permitting the starter operation, and at least the engine rotation speed calculated for each predetermined processing cycle in the engine rotation speed calculation step is greater than the engagement permission rotation speed. Is less than the meshing prohibition speed specified as a small value. It is determined at every predetermined processing cycle whether the rotation speed is below the meshing prohibition rotation speed, the determination result is prohibited, and the prohibition determination step for prohibiting the starter operation, the permission determination step, and the prohibition determination step And a starter control step for determining whether or not to operate the starter for each predetermined processing cycle based on the determination result. In the starter control step, in the current processing cycle for each predetermined processing cycle, the permission determination step In the case where the determination result is permitted and the determination result in the prohibition determination step is prohibited, the determination result in the prohibition determination step is prioritized and the starter operation is prohibited.

  According to the present invention, based on the engine speed, the meshing permission determination and the meshing prohibition determination are performed in consideration of the switching between the permission and prohibition of the starter meshing and the prohibition and the processing cycle while the engine speed is decreasing, and the determination based on the meshing permission determination. When the result is permitted and the determination result by the meshing prohibition determination is prohibited, the determination result of the meshing prohibition determination has priority. As a result, even when the engine rotational fluctuation is large, restarting during inertial rotation of the engine in the engine automatic stop and start system can be promptly performed while suppressing the impact when the pinion gear and the ring gear mesh. In addition, an engine starter and an engine start method that can be performed silently can be obtained.

It is a block diagram which shows schematic structure of the engine starting apparatus in Embodiment 1 of this invention. It is sectional drawing which shows schematic structure of the starter of the engine starting apparatus in Embodiment 1 of this invention. It is a graph which shows the engine rotation behavior during the inertial rotation by Embodiment 1 of this invention. It is a flowchart which shows a series of processes in Embodiment 1 of this invention. It is a flowchart which shows a series of processes regarding the engine restart control when the restart conditions are satisfied in Embodiment 1 of the present invention. It is a flowchart which shows a series of processes regarding the meshing permission determination in Embodiment 1 of this invention. It is a flowchart which shows a series of processes regarding the meshing prohibition determination in Embodiment 1 of this invention. It is a flowchart which shows a series of processes regarding the starter control in Embodiment 1 of this invention. It is a graph which shows the relationship between the engine rotational behavior in the inertial rotation by Embodiment 1 of this invention, and the engine rotational speed in a process period.

  Hereinafter, an engine starter and an engine start method according to the present invention will be described with reference to the drawings according to a preferred embodiment, taking as an example the case of application to a four-cylinder engine. In the description of the drawings, the same reference numerals are assigned to the same elements, and duplicate descriptions are omitted.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a schematic configuration of an engine starter 1 according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view showing a schematic configuration of the starter of engine starter 1 according to Embodiment 1 of the present invention.

  The engine starter 1 according to the first embodiment shown in FIG. 1 includes a controller 10, a ring gear 11, a relay 12, a starter motor 13, a pinion gear 14, and a one-way clutch 15 (not shown in FIG. 1, but shown in FIG. And a power source 16 (battery) and a pinion gear moving unit 20. The pinion gear moving unit 20 is specifically configured to include the plunger 21, the solenoid 22, and the lever 23, but is not limited thereto.

  FIG. 2, which is a cross-sectional view showing a schematic configuration of the starter, includes a starter motor 13, a pinion gear 14, a one-way clutch 15, and a pinion gear moving unit 20 (plunger 21, solenoid 22 and lever) as specific starter configurations. 23) and the ring gear 11 are also shown. The starter includes a starter motor 13 for starting the engine, a pinion gear 14 that transmits the rotation of the starter motor 13 to the ring gear 11, and a pinion gear moving unit 20 that moves the pinion gear 14 to mesh with the ring gear 11. It suffices to be configured to include at least.

  The controller 10 controls energization to the solenoid 22 via the relay 12 provided between the power source 16 and the solenoid 22. Then, the controller 10 attracts the plunger 21 by energizing the solenoid 22 and moves the pinion gear 14 via the lever 23 to mesh the pinion gear 14 with the ring gear 11. Further, the contact is closed by the movement of the plunger 21 and the starter motor 13 is energized, whereby the pinion gear 14 rotates. The ring gear 11 meshes with the pinion gear 14 and transmits driving force to the engine.

  After the engine start is completed, the controller 10 stops energizing the solenoid 22. Then, according to the operation of a plunger spring (not shown) connected to the plunger 21, the plunger 21 moves in a direction to release the engagement between the pinion gear 14 and the ring gear 11. Thereby, the meshing between the pinion gear 14 and the ring gear 11 is released via the lever 23, and the energization to the starter motor 13 is stopped.

  The one-way clutch 15 is connected to the output shaft of the starter motor 13, and rotates idly when the rotational speed of the ring gear 11 is higher than the rotational speed of the starter motor 13. When the rotational speed of the ring gear 11 becomes higher than that of the ring gear 11, it is locked and the rotational torque is transmitted.

  A crank angle sensor (not shown) detects a pulse corresponding to the rotation angle (crank angle) of the engine. In the first embodiment, as a specific example, a pulse is generated every 30 degrees of crank angle.

  The period of the pulses detected by the crank angle sensor corresponds to the time required for the engine to rotate by a predetermined angle. Therefore, the controller 10 can calculate the engine rotation speed based on the cycle of the rotation pulse of the crankshaft output from the crank angle sensor. In the first embodiment, as a specific example, the controller 10 calculates the engine rotation speed every predetermined processing cycle (for example, every 10 ms), and performs control using the calculated engine rotation speed at the time of control execution. Do.

  In order to avoid confusion, the rotational speeds of the ring gear 11 and the pinion gear 14 and the like in the present invention are all converted to the rotational speed of the crankshaft and unified.

  In the first embodiment, the controller 10 may be configured by an engine ECU that performs engine control, or may be configured as an ECU that executes an engine automatic stop / start system separately from the engine ECU. In addition to the above, it may be configured as an ECU dedicated to the control of the starter.

  Next, the engine inertia rotation behavior when the engine automatic stop condition is satisfied in the engine starter 1 of the first embodiment will be described with reference to FIG. FIG. 3 is a graph showing engine rotation behavior during inertial rotation according to Embodiment 1 of the present invention. Specifically, it shows the behavior of the engine rotation speed with the passage of time when the fuel supply to the engine is stopped and the inertia rotation is performed because the engine automatic stop condition is satisfied.

  Here, when the engine automatic stop condition (for example, the vehicle speed is 15 km / h or less and the driver is stepping on the brake) is satisfied while the vehicle is traveling, the fuel supply to the engine is stopped and the inertia is rotated. .

  As a result of the inertia rotation, as shown in FIG. 3, the torque fluctuation occurs due to the compression / expansion cycle of the engine piston, and the engine rotation speed decreases while causing pulsation. Further, once the engine rotation speed becomes 0 rpm, the torque is attenuated while repeating reverse rotation and forward rotation due to torque fluctuation and friction.

  Here, according to the present invention, when the engine is restarted because the restart condition is satisfied during the inertia rotation of the engine after the engine automatic stop condition is satisfied, the meshing permission determination and the When the engine speed is within the meshing allowable rotational speed range by performing the meshing prohibition determination while considering the switching between the permission and prohibition of the starter meshing and the processing cycle while the engine speed is decreasing, the starter operation is performed. The technical feature is that when the engine speed is permitted and the engine speed is not within the meshing allowable speed range, the operation of the starter is prohibited.

  Here, as shown in FIG. 3, the meshing allowable rotation speed range is defined by the meshing allowable range upper limit rotational speed and the meshing allowable range lower limit rotational speed respectively indicated by broken lines. FIG. 3 also shows a meshing allowable rotation speed NE1 and a meshing prohibition rotational speed NE2 (described later) indicated by a one-dot chain line.

  Next, a specific operation of the engine starting device 1 according to the first embodiment will be described in detail with reference to FIG. FIG. 4 is a flowchart showing a series of processes related to engine restart in the first embodiment of the present invention. Regarding the technical features of the present invention, as a specific example of the operation of the starter, an operation of meshing the pinion gear 14 and the ring gear 11 is illustrated. Further, the controller 10 executes the series of processes in the flowchart in FIG. 4 for each processing cycle described above.

  First, in step S100, the controller 10 determines whether or not an engine automatic stop condition is satisfied. In step S100, when it is determined that the engine automatic stop condition is not satisfied, the controller 10 ends the series of processes and proceeds to the next processing cycle.

  On the other hand, if it is determined in step S100 that the engine automatic stop condition is satisfied, the controller 10 proceeds to step S101 and starts engine stop control. Specifically, the controller 10 stops the fuel supply to the engine and reduces the rotational speed of the engine by inertial rotation.

  Next, in step S102, the controller 10 determines whether or not the engine is completely stopped. For example, the determination is made based on whether or not a crank angle pulse is detected during a predetermined time (for example, 300 ms). Therefore, if the crank angle pulse is not detected within a predetermined time, the controller 10 determines that the engine is completely stopped, ends the series of processing, and proceeds to the next processing cycle.

  On the other hand, if the controller 10 determines in step S102 that the engine is not completely stopped, the controller 10 proceeds to step S103 and determines whether or not a restart condition (for example, the driver releases the brake) is satisfied. Determine.

  In Step S103, when it is determined that the restart condition is satisfied, the controller 10 proceeds to Step S104 and performs engine restart control. On the other hand, if it is determined in step S103 that the restart condition is not satisfied, the controller 10 ends the series of processes and proceeds to the next processing cycle.

  Although not shown, the controller 10 once determines that the restart condition is satisfied and starts the engine restart control. In step S100 in the subsequent processing cycle, the engine automatic stop condition is determined. Suppose that is not established. Even in such a case, the controller 10 continues the engine restart control by a flag or the like and restarts the engine.

  Next, the engine restart control in step S104 will be described in detail with reference to FIG. FIG. 5 is a flowchart showing a series of processes relating to engine restart control according to Embodiment 1 of the present invention.

  First, in step S200, the controller 10 starts the engine stop behavior prediction, updates the engine rotation speed at the current processing timing (processing cycle) from the engine rotation speed at the previous processing timing, and proceeds to step S201. move on. This step S200 is executed by an engine speed calculation unit included in the controller 10.

  Further, as described above, the engine rotation speed is calculated based on the pulse period for each predetermined angular interval detected by the crank angle sensor. As a specific example, when the cycle between BTDC 60 ° and BTDC 30 ° is 40 ms, the engine speed NE at the processing timing after the pulse corresponding to BTDC 30 ° is input is given by the following equation (1). Is calculated. In this specific example, the engine speed NE is calculated as 125 rpm.

  Further, since the engine speed NE is updated every processing cycle (for example, 10 ms) of the controller 10, the engine speed NE is updated at the first processing timing after the pulse corresponding to BTDC 30 ° is input. The Rukoto.

  Note that the engine speed NE may be updated by performing an interrupt process when a pulse from the crank angle sensor is received without waiting for the processing timing of the processing cycle. Further, the engine rotation speed NE may be updated by generating a virtual pulse for each processing cycle and reducing the engine rotation speed NE based on the cycle of the virtual pulse.

  Next, in step S201, the controller 10 performs a meshing permission determination based on the engine speed NE updated in step S200. This step S201 is executed by the permission determination unit included in the controller 10.

  In this step S201, when the solenoid 10 is energized, the controller 10 reaches the ring gear 11 with a delay time Td (when the pinion gear 14 and the ring gear 11 are engaged). By determining whether or not the engine rotation speed is equal to or lower than the engagement allowable range upper limit rotation speed, the engagement permission determination is performed.

  Specifically, the controller 10 performs the engagement permission determination in step S201 according to the flowchart of FIG. FIG. 6 is a flowchart showing a series of processes relating to the meshing permission determination in the first embodiment of the present invention.

  First, in step S300, the controller 10 determines whether or not the engagement permission flag F1 is established (“F1 = 1” is established). Thereby, it is determined whether or not the engagement permission condition is satisfied.

  In step S300, if the controller 10 determines that the engagement permission flag F1 is satisfied ("F1 = 1" is satisfied), the engagement permission condition has already been satisfied. The meshing permission determination is terminated. In the flowchart of FIG. 6, the initial value is “F1 = 0” until the meshing permission condition is satisfied for the first time.

  On the other hand, if the controller 10 determines in step S300 that the meshing permission flag F1 is not established ("F1 = 1" is not established, and "F1 = 0" is established), step S301 is performed. It is determined whether or not the engine speed NE is equal to or less than the meshing permission speed NE1.

  Here, the meshing between the pinion gear 14 and the ring gear 11 will be described. When the difference between the rotation speed of the pinion gear 14 and the rotation speed of the ring gear 11 is large, an impact or noise is generated at the time of meshing. Therefore, it is necessary to mesh the pinion gear 14 and the ring gear 11 within the meshing allowable rotational speed range defined by the meshing allowable range upper limit rotational speed and the meshing allowable range lower limit rotational speed.

  Further, the meshing between the pinion gear 14 and the ring gear 11 due to energization of the solenoid 22 causes a delay time Td from the start of energization of the solenoid 22 to the completion of the arrival of the pinion gear 14 to the ring gear 11. Therefore, it is necessary to consider this delay time Td when meshing the gears. Therefore, the meshing permission rotation speed NE1 is set in consideration of the above. Specifically, the meshing allowable rotation speed NE1 is a value at a time point Td back from the time when the engine rotation speed becomes the meshing allowable range upper limit rotation speed.

  With this setting, energization of the solenoid 22 is started at a rotational speed equal to or lower than the meshing allowable rotational speed NE1, and as a result, after the delay time Td elapses, the engine rotational speed becomes the allowable upper limit rotational speed. It will be engaged in the following.

  In step S301, if the controller 10 determines that the engine speed NE is equal to or lower than the meshing permission rotational speed NE1, the controller 10 proceeds to step S302, and changes the meshing permission flag F1 from “F1 = 0” to “F1 = 1”. ", The series of processes in the flowchart of FIG. Thereby, the meshing permission determination process in step S201 ends.

  On the other hand, if the controller 10 determines in step S301 that the engine speed NE is higher than the meshing permission rotational speed NE1, the controller 10 does not change the meshing permission flag F1 (in the state of “F1 = 0”). A series of processes in the flowchart of FIG. Thereby, the meshing permission determination in step S201 ends.

  Next, returning to the description of FIG. 5, the controller 10 proceeds to step S <b> 202 after the meshing permission determination in step S <b> 201 is completed, and performs the meshing prohibition determination based on the engine speed NE updated in step S <b> 200. . This step S202 is executed by a prohibition determination unit included in the controller 10.

  In step S202, the controller 10 is energized to the solenoid 22, and when the pinion gear 14 reaches the ring gear 11 with a delay time Td (when the pinion gear 14 and the ring gear 11 are engaged). By determining whether or not the engine rotation speed is equal to or lower than the meshing allowable range lower limit rotation speed, the meshing prohibition determination is performed.

  Specifically, the controller 10 performs the engagement prohibition determination in step S202 according to the flowchart of FIG. FIG. 7 is a flowchart showing a series of processes relating to the meshing prohibition determination in the first embodiment of the present invention.

  First, in step S400, the controller 10 determines whether or not the meshing prohibition flag F2 is established (“F2 = 1” is established). Thereby, it is determined whether or not the meshing prohibition condition is satisfied.

  In step S400, if the controller 10 determines that the meshing prohibition flag F2 is not established ("F2 = 1" is not established and "F2 = 0" is established), step S401 is performed. To determine whether the engine speed NE is equal to or less than the meshing prohibition speed NE2. In the flowchart of FIG. 7, the initial value is “F2 = 0” until the meshing prohibition condition is satisfied for the first time.

  Here, the meshing prohibition rotational speed NE2 is set in consideration of the meshing allowable range lower limit rotational speed and the delay time Td. Specifically, the meshing prohibition rotational speed NE2 is a value at a time point Td back from the time when the engine rotational speed becomes the meshing allowable range lower limit rotational speed. With this setting, energization of the solenoid 22 is started at a rotational speed that is higher than the meshing prohibition rotational speed NE2, and as a result, the engine rotational speed is within the allowable range lower limit rotation after the delay time Td has elapsed. The meshing occurs at a rotational speed higher than the speed.

  In step S401, if the controller 10 determines that the engine speed NE is equal to or lower than the meshing prohibition rotational speed NE2, the controller 10 proceeds to step S402 and changes the meshing prohibition flag F2 from “F2 = 0” to “F2 = 1”. "

  Next, the controller 10 proceeds to step S403, and sets a timer for measuring a predetermined time. Specifically, the controller 10 sets the count Tc of the prohibit timer to Tn, and ends the series of processes in the flowchart of FIG. Thereby, the meshing prohibition determination in step S202 ends. Step S403 is executed by a timer setting unit included in the controller 10, and a starter control unit to be described later instructs the timer setting unit to set a timer. The starter control unit itself may also serve as the function of the timer setting unit.

  Here, after the engine rotational speed NE becomes equal to or lower than the meshing prohibition rotational speed NE2, Tn is again the rotational speed at which the pinion gear 14 reaches the ring gear 11 at a rotational speed higher than the meshing allowable range lower limit rotational speed. It is set in consideration of the time. That is, the controller 10 determines the elapse of the predetermined time based on the timer by setting the timer.

  On the other hand, in step S401, if the controller 10 determines that the engine speed NE is higher than the meshing prohibition rotational speed NE2, the controller 10 does not change the meshing prohibition flag F2 (in the state of “F2 = 0”). A series of processes in the flowchart of FIG. Thereby, the meshing prohibition determination in step S202 ends.

  In step S400, if the controller 10 determines that the meshing prohibition flag F2 is satisfied ("F2 = 1" is satisfied), the meshing prohibition condition has already been satisfied. Proceed to step S404.

  In step S404, the controller 10 decrements the count of the prohibit timer Tc by 1 (that is, Tc = Tc-1), and ends the series of processes in the flowchart of FIG. Thereby, the meshing prohibition determination in step S202 ends. As described above, when the meshing prohibition flag F2 is established, the controller 10 executes step S404 in each processing cycle, whereby the count of the prohibition timer Tc is decremented by one. As a result, if the prohibit timer Tc becomes Tc ≦ 0, the controller 10 determines that a predetermined time has elapsed and cancels the mesh prohibition.

  Next, returning to the description of FIG. 5, the controller 10 proceeds to step S <b> 203 after the meshing prohibition determination in step S <b> 202 is completed, and starts control based on the meshing permission determination in step S <b> 201 and the meshing prohibition determination in step S <b> 202. I do. This step S203 is executed by a starter control unit included in the controller 10.

  Specifically, the controller 10 performs the starter control in step S203 according to the flowchart of FIG. FIG. 8 is a flowchart showing a series of processes related to the starter control in the first embodiment of the present invention.

  First, in step S500, the controller 10 determines whether or not the meshing prohibition flag F2 is established (“F2 = 1” is established).

  In step S500, when it is determined that the meshing prohibition flag F2 is established ("F2 = 1" is established), the controller 10 proceeds to step S501 and determines the count of the inhibition timer Tc.

  On the other hand, if the controller 10 determines in step S500 that the meshing prohibition flag F2 is not established ("F2 = 1" is not established, and "F2 = 0" is established), step S502 is performed. Proceed to

  In step S501, the controller 10 determines whether or not the prohibit timer Tc satisfies Tc ≦ 0 (that is, whether or not the mesh prohibition is cancelled). In step S501, if the controller 10 determines that the prohibit timer Tc satisfies Tc ≦ 0 (that is, the prohibition of meshing is released), the controller 10 proceeds to step S502.

  On the other hand, if it is determined in step S501 that the prohibit timer Tc satisfies Tc> 0 (that is, the prohibition of meshing has not been released), the controller 10 ends the series of processes in the flowchart of FIG. To do. As a result, the starter control in step S203 is completed, so the controller 10 ends the series of processes in the flowchart of FIG. 4 and proceeds to the next processing cycle.

  Further, in step S502, the controller 10 determines whether or not the meshing permission flag F1 is established (“F1 = 1” is established). If the controller 10 determines in step S502 that the engagement permission flag F1 is established ("F1 = 1" is established), the process proceeds to step S503.

  On the other hand, if the controller 10 determines in step S502 that the meshing permission flag F1 is not established ("F1 = 1" is not established, and "F1 = 0" is established), FIG. The series of processes in the flowchart of FIG. As a result, the starter control in step S203 is completed, so the controller 10 ends the series of processes in the flowchart of FIG. 4 and proceeds to the next processing cycle.

  Here, step S500 and step S501 are executed before step S502, so that the engagement prohibition flag F1 is not established (step S502), but the engagement prohibition flag F2 is not established (step S500) or the engagement inhibition is released. The determination (step S501) is prioritized.

  FIG. 9 is a graph showing the relationship between the engine rotation behavior during inertial rotation and the engine rotation speed in the processing cycle according to Embodiment 1 of the present invention. For example, as shown in FIG. 9, in the previous processing cycle, the meshing permission flag F1 is not established (F1 = 0) and the meshing prohibition flag F2 is not established (F2 = 0) based on the updated engine speed NE. Suppose that it was.

  In this case, in the current processing cycle subsequent to the previous processing cycle, the meshing permission flag F1 is established (F1 = 1) and the meshing prohibition flag F2 is established (F2) based on the updated engine speed NE. = 1), the determination result based on the engagement prohibition determination has priority, and the engagement between the pinion gear 14 and the ring gear 11 is prohibited (not performed). In other words, since the meshing permission determination and the meshing prohibition determination are performed at predetermined processing cycles set shorter than the engine rotation fluctuation cycle, the engine rotation fluctuation is large, and even if such a case occurs, the pinion The meshing between the gear 14 and the ring gear 11 is not permitted. Therefore, as a result, it is possible to avoid meshing below the meshing allowable range lower limit rotational speed.

  Further, in step S503, the controller 10 energizes the solenoid 22, meshes the pinion gear 14 and the ring gear 11 by the movement of the plunger 21, and proceeds to step S504.

  In step S504, the controller 10 closes the contact point by the movement of the plunger 21, thereby energizing the starter motor 13, rotates the pinion gear 14, and proceeds to step S505.

  In step S505, the controller 10 restarts fuel injection into the engine, restarts the engine by cranking, and ends a series of processes in the flowchart of FIG. Further, when the engine is restarted, the controller 10 returns the meshing permission flag F1 and the meshing prohibition flag F2 to the initial values of zero (“F1 = 0”, F2 = 0 ”). As a result, the starter control in step S203 is completed, so the controller 10 ends the series of processes in the flowchart of FIG. 4 and proceeds to the next processing cycle.

  As described above, when the permission based on the meshing permission determination (the meshing permission flag F1 is established) and the prohibition based on the meshing prohibition determination (the meshing prohibition flag F2 is established) are simultaneously established in this processing cycle, the meshing prohibition determination is performed. The judgment result has priority. In this case, the controller 10 prohibits the operation of the pinion gear moving unit 20 so that the meshing is not performed. Further, even when the prohibition by the meshing prohibition determination is not released based on the prohibition timer Tc, the controller 10 similarly prohibits the operation of the pinion gear moving unit 20 so that the meshing is not performed.

  As a result, even when the engine rotational fluctuation is large, the engine automatically stops while avoiding meshing below the meshing allowable range lower limit rotational speed and suppressing the impact when the pinion gear 14 and the ring gear 11 mesh. The restart during the inertial rotation of the engine in the starting system can be performed promptly and silently, so that the driver does not feel uncomfortable. Furthermore, it is possible to achieve a reduction in noise when the pinion gear 14 and the ring gear 11 mesh with each other and an increase in the service life of the parts.

  As described above, according to the first embodiment, the determination result by the meshing permission determination is permitted in the current processing cycle during the engine rotation speed decrease period in which the engine rotation speed decreases due to the inertia rotation due to the stop of fuel supply. When the determination result based on the meshing prohibition determination is prohibited, the determination result based on the meshing prohibition determination is given priority and the starter operation is prohibited. As a result, even when the rotational fluctuation of the engine is large, it is possible to avoid meshing below the meshing allowable range lower limit rotational speed, and to suppress the impact at the time of meshing between the pinion gear and the ring gear.

  In the first embodiment, as an example of the starter operation, the pinion gear 14 and the ring gear 11 are engaged with each other using a starter configured to continuously move the pinion gear and drive the motor. Although the operation has been illustrated and described, the present invention is not limited to this. That is, the present invention may be applied to a starter configured to be able to operate independently. In this case, for example, instead of prohibiting the movement of the pinion gear, the operation of the motor may be prohibited.

  Further, in the first embodiment, in the flowchart of FIG. 7, when the meshing prohibition flag F2 is established, the prohibition timer Tc is introduced in order to consider the cancellation of the meshing prohibition after a predetermined time has elapsed. Although illustrated, it is not limited to this. That is, if the release of the mesh prohibition is not considered, the prohibit timer Tc may not be introduced. In this case, steps S403 and S404 in the flowchart in FIG. 7 and step S501 in the flowchart in FIG. 8 are omitted.

  DESCRIPTION OF SYMBOLS 1 Engine starter, 10 Controller, 11 Ring gear, 12 Relay, 13 Starter motor, 14 Pinion gear, 15 One-way clutch, 16 Power supply (battery), 20 Pinion gear moving part, 21 Plunger, 22 Solenoid, 23 Lever

Claims (5)

A starter to start the engine,
An engine rotation speed calculation unit for calculating the engine rotation speed for each predetermined processing cycle;
It is determined at each predetermined processing cycle whether or not the engine rotational speed calculated at least by the engine rotational speed calculation unit at each predetermined processing cycle is equal to or less than the meshing permitted rotational speed, and the meshing permitted rotational speed. If it is the following, with the determination result as permission, a permission determination unit that permits the operation of the starter;
Whether or not the engine rotation speed calculated at least by the engine rotation speed calculation unit for each predetermined processing cycle is equal to or lower than a meshing prohibition rotation speed defined as a value smaller than the meshing permission rotation speed. A prohibition determination unit that prohibits the operation of the starter by prohibiting the determination result when the rotation speed is equal to or lower than the meshing prohibition rotation speed;
A starter control unit that determines whether or not to operate the starter for each predetermined processing cycle based on determination results by the permission determination unit and the prohibition determination unit;
With
The starter control unit
If the determination result by the permission determination unit is permitted and the determination result by the prohibition determination unit is prohibited in the current processing cycle for each predetermined processing cycle, the determination result by the prohibition determination unit is given priority. And an engine starter that prohibits the operation of the starter. The engine starter according to claim 1,
The starter is
A pinion gear for meshing with the engine ring gear;
A starter motor for rotating the pinion gear;
By moving the pinion gear to the position of the ring gear, a pinion gear moving unit that meshes the pinion gear and the ring gear;
Have
The starter control unit
An engine starter that controls the pinion gear moving unit not to move the pinion gear to the position of the ring gear when the starter operation is prohibited by giving priority to the determination result by the prohibition determining unit. The engine starter according to claim 1,
The starter is
A pinion gear for meshing with the engine ring gear;
A starter motor for rotating the pinion gear;
By moving the pinion gear to the position of the ring gear, a pinion gear moving unit that meshes the pinion gear and the ring gear;
Have
The starter control unit
An engine starter that controls the starter motor not to rotate the pinion gear when the starter operation is prohibited by giving priority to the determination result by the prohibition determination unit. The engine starting device according to any one of claims 1 to 3,
It further includes a timer for measuring the elapsed time of the processing cycle,
The starter control unit
Measurement of elapsed time by the timer is started in the processing cycle when the determination result by the prohibition determination unit is switched to prohibition, and the measurement time by the timer elapses a predetermined time or more in the processing cycle after starting measurement by the timer An engine starter that cancels the prohibition that is the determination result by the prohibition determination unit when it is determined that the prohibition determination unit has determined. An engine start method executed by a controller in an engine starter having a starter for starting an engine,
An engine speed calculating step for calculating an engine speed for each predetermined processing cycle;
It is determined at each predetermined processing cycle whether or not the engine rotational speed calculated at least every predetermined processing cycle in the engine rotational speed calculating step is equal to or less than the meshing allowable rotational speed, and the meshing allowable rotational speed. If it is the following, with the determination result as permission, a permission determination step for permitting the operation of the starter;
Whether or not the engine rotation speed calculated at the predetermined processing period at least in the engine rotation speed calculation step is equal to or less than a meshing prohibition rotation speed defined as a value smaller than the meshing permission rotation speed. A determination step that prohibits the operation of the starter by prohibiting the determination result when the rotation speed is equal to or lower than the meshing prohibition rotation speed;
A starter control step for determining whether or not to operate the starter for each predetermined processing cycle based on the determination results of the permission determination step and the prohibition determination step;
With
In the starter control step,
If the determination result in the permission determination step is permitted and the determination result in the prohibition determination step is prohibited in the current processing cycle for each predetermined processing cycle, the determination result in the prohibition determination step is given priority. And an engine starting method for prohibiting the operation of the starter.

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