JP2012002168A - Starter for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a starter for an internal combustion engine capable of restraining noise from being generated caused by an operation of a switching mechanism.SOLUTION: The starter includes the switching mechanism for switching a connection state to a non-connection state and vice versa between a pinion gear provided in an output shaft of a starter motor 20 and a ring gear provided an engine output shaft. An electronic control unit 30 conducts electric power supply from a battery 19 to the starter motor 20 and electric power supply to an electromagnetic solenoid 27a, respectively, at individual different timing based on individual different command signals. The electronic control unit 30 starts the electric power supply to the electromagnetic solenoid 27a in a stop process of an engine operation in order to bring the connection state of the pinion gear to the ring gear prior to the satisfaction of an engine start-up condition, and starts, in the other hand, the electric power supply to the starter motor 20 with on condition that the engine start-up condition is satisfied. The electromagnetic solenoid 27a is connected to the battery 19 via a variable resistor 42.

Description

  The present invention relates to a starter for an internal combustion engine that applies an auxiliary torque to an engine output shaft when the engine is started.

  Generally, an internal combustion engine starter includes a starter motor that generates a rotational force, and a switching mechanism that switches connection / disconnection of the output shaft of the starter motor and the engine output shaft. When the start of the internal combustion engine is requested by operating the operation switch or the like, first, the switching mechanism is actuated so that the motor output shaft and the engine output shaft are connected (connected state). Thereafter, driving of the starter motor is started. Through such a series of operations, when the engine is started, the starter motor is driven to apply auxiliary rotational torque to the engine output shaft. Normally, in an internal combustion engine starter, the operation of such a switching mechanism and the drive of a starter motor are executed as a series of operations based on a common command signal (for example, operation of an operation switch).

  Conventionally, it has been proposed to operate the switching mechanism and drive the starter motor at arbitrary timings based on different command signals (see Patent Document 1). In this device, the switching mechanism operates so that the engine output shaft and the motor output shaft are connected when the operation of the internal combustion engine is stopped. After that, when the start of the internal combustion engine is requested, the starter motor starts to be driven. In this apparatus, since the engine output shaft and the motor output shaft are connected in advance when the operation of the internal combustion engine is stopped, it is not necessary to operate the switching mechanism when starting the internal combustion engine. As a result, the starter motor can be driven early, and the engine start can be completed early.

JP 2002-89422 A

  An internal combustion engine starter includes a first gear connected to a motor output shaft and a second gear connected to the engine output shaft. When switching from the state where the motor output shaft and the engine output shaft are not connected (non-connected state) to the connected state, the first gear is moved and meshed with the second gear through the operation of the switching mechanism. Become. Therefore, at this time, it is inevitable that a sound (hereinafter referred to as “meshing sound”) is generated due to the meshing of the first gear and the second gear, and this meshing sound may become noise.

  Here, if the operation of the switching mechanism and the drive of the starter motor are performed as a series of operations based on a common command signal, such a meshing sound is generated by a series of engines for starting the engine such as a cranking operation. Since there is a high possibility that the sound is generated as a result of the movement, the possibility of noise is low.

  On the other hand, in the device in which the operation of the switching mechanism and the drive of the starter motor are performed at arbitrary timings based on different command signals, as in the device of Patent Document 1 described above, when the engine is stopped, the engine output shaft The motor output shaft is connected in advance. For this reason, when the engine operation is stopped or stopped, that is, when the sound generated during engine operation (hereinafter referred to as “dark noise”) is small, the switching mechanism operates and generates a meshing sound. Is prominent and likely to be noisy.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a starting device for an internal combustion engine that can suppress generation of noise due to operation of a switching mechanism.

In the following, means for achieving the above object and its operational effects will be described.
The invention according to claim 1 is a solenoid-driven switching mechanism that switches between a connected state and a disconnected state between a first gear provided on the output shaft of the starter motor and a second gear provided on the engine output shaft, And a battery that supplies power to the starter motor and the drive solenoid of the switching mechanism, and power supply to the starter motor and power supply to the drive solenoid based on different command signals, respectively. The control unit is executed at different timings, and the control unit stops the engine operation or stops the engine so that the first gear and the second gear are connected prior to establishment of the engine start condition. An internal combustion engine that starts supplying power to the drive solenoid and starts supplying power to the starter motor on condition that the engine start condition is satisfied In the starting device, and its gist in that said said drive solenoid battery is connected through a resistor.

  In the above configuration, when the internal combustion engine is stopped or stopped, that is, when the background noise is small, power is supplied to the drive solenoid and the switching mechanism is operated. At this time, the first gear and the second gear mesh with each other. As a result, a meshing sound is generated. However, according to the above configuration, since the resistor is provided between the driving solenoid and the battery, the inrush current of the driving solenoid can be suppressed to be smaller than that of the device not provided with the resistor. . Therefore, the magnetic force generated by the drive solenoid can be reduced, and the moving speed of the movable part of the switching mechanism, and hence the moving speed of the first gear can be reduced. As described above, according to the above configuration, although the first gear and the second gear are engaged with each other in a low background noise state, the engagement sound associated with the engagement can be suppressed to a low level. The generation of noise due to can be suppressed.

The gist of the invention described in claim 2 is that the starting device for the internal combustion engine according to claim 1 further comprises setting means for variably setting the resistance value of the resistor.
According to the above configuration, the resistance value of the resistor can be appropriately set with a high degree of freedom, for example, by setting the resistance value of the resistor in accordance with a change in the state of the battery (deterioration state or remaining amount). It becomes like this.

  According to a third aspect of the present invention, in the starter for an internal combustion engine according to the second aspect, the starter further includes an estimation unit that estimates a remaining amount of the battery, and the setting unit includes The gist is to set a smaller value as the resistance value as the remaining amount estimated by the estimating means is smaller.

  When the remaining amount of the battery decreases, the power supplied from the battery to the drive solenoid may decrease. In this case, the magnetic force generated by the drive solenoid is reduced, and the moving speed of the movable part of the switching mechanism is reduced. Such a change in the operating characteristics of the switching mechanism due to the change in the remaining battery level is not preferable because it causes a destabilization of the starting function of the internal combustion engine.

  In this regard, according to the above configuration, the resistance value of the resistor is decreased to increase the supply power to the drive solenoid as the supply power to the drive solenoid decreases because the remaining amount of the battery is low. Thus, the change in the supplied power can be suppressed. Therefore, it is possible to suppress changes in the operating characteristics of the switching mechanism due to changes in the remaining battery capacity.

  The invention according to claim 4 is the internal combustion engine starter according to any one of claims 1 to 3, wherein the starter automatically stops the internal combustion engine when a stop condition is satisfied, The gist of the present invention is that the present invention is applied to an engine system that performs automatic stop start control for automatically starting the internal combustion engine when a restart condition is satisfied.

  In recent years, in order to reduce fuel consumption and emissions, for example, temporarily stop the operation of the in-vehicle internal combustion engine when the vehicle stops at an intersection or the like (for example, control for intermittently stopping the operation of the internal combustion engine ( An engine system for executing automatic stop / start control has been proposed and put into practical use. When such an engine system is adopted, there is a demand for completing the restart of the internal combustion engine at an early stage. Therefore, the power supply to the starter motor and the power supply to the solenoid described above are based on different command signals. Therefore, there is a high possibility that a configuration of executing at different timings will be adopted.

  According to the above configuration, in the starting device applied to such an engine system, it is possible to reduce the meshing sound accompanying the meshing of the first gear and the second gear, and to suppress the generation of noise due to the operation of the switching mechanism. it can.

  According to a fifth aspect of the present invention, in the starter for an internal combustion engine according to the fourth aspect, the control unit performs the driving when the stop condition is satisfied and the engine rotational speed decreases to a predetermined speed or less. The main point is to start the power supply to the solenoid.

  In the above configuration, since the switching mechanism operates in the process in which the operation of the internal combustion engine is automatically stopped, that is, in the situation where the background noise is small, the meshing noise is generated. Is expensive. According to the above configuration, it is possible to suppress the meshing sound accompanying the meshing of the first gear and the second gear when the engine operation is automatically stopped.

1 is a schematic diagram showing a schematic configuration of a vehicle to which a starter for an internal combustion engine according to an embodiment embodying the present invention is applied. 1 is a schematic diagram showing a schematic configuration of a starter according to the embodiment. The circuit diagram which shows the electric circuit of the starter. The timing chart which shows an example of transition of the electric current amount which flows through an electromagnetic solenoid. The flowchart which shows the execution procedure of resistance value setting processing. The schematic diagram which shows the specific structure of a variable resistor. The circuit diagram which shows the electric circuit of the starting device concerning other embodiment.

Hereinafter, a starter for an internal combustion engine according to an embodiment of the present invention will be described.
FIG. 1 shows a schematic configuration of a vehicle to which the starting device according to the present embodiment is applied.

  As shown in FIG. 1, the vehicle 10 includes an internal combustion engine 11 as a drive source. A crankshaft 12 of the internal combustion engine 11 is connected to a transmission 13. An output shaft (not shown) of the transmission 13 is connected to a wheel 17 via a drive shaft 14, a differential gear 15, and an axle 16. An alternator 18 is connected to the crankshaft 12. The vehicle 10 is provided with a battery 19 that supplies power to various electrical components. The battery 19 is charged by the power generated by the alternator 18.

  A starter motor 20 that generates torque is mounted on the vehicle 10. The starter motor 20 is driven when the internal combustion engine 11 is started, and the rotational force is transmitted to the crankshaft 12. Thereby, starting of the internal combustion engine 11 is assisted.

  The vehicle 10 includes various sensors for detecting the operation state and the operation state of the internal combustion engine 11. Examples of such sensors include a crank sensor 31 for detecting the rotational speed of the crankshaft 12 (engine rotational speed NE) of the internal combustion engine 11, an accelerator sensor 32 for detecting the depression amount of the accelerator pedal 21, and engine cooling. A temperature sensor 33 is provided for detecting the temperature of the water (cooling water temperature THW). Further, a brake sensor 34 for detecting whether or not the brake pedal 22 is depressed and a speed sensor 35 for detecting the traveling speed of the vehicle 10 are provided. In addition, a voltage sensor 36 for detecting the voltage of the battery 19, an operation switch 37 that is operated by an occupant when the internal combustion engine 11 is started or stopped are provided.

  Further, the vehicle 10 is provided with an electronic control unit 30 configured with, for example, a microcomputer. The electronic control unit 30 takes in the detection signals of the sensors and performs various calculations, and executes various controls such as fuel injection control and ignition timing control based on the calculation results.

  As one of various controls, the electronic control unit 30 automatically stops the internal combustion engine 11 when the vehicle 10 stops at an intersection or the like, and automatically starts the internal combustion engine 11 at an arbitrary timing during the automatic stop. The automatic stop / start control is executed to make the vehicle startable. In the engine system of the present embodiment, the fuel consumption and emission of the internal combustion engine 11 can be reduced through execution of automatic stop / start control.

Hereinafter, the process (automatic stop start process) concerning the automatic stop start control will be described in detail.
Here, first, a process for automatically stopping the internal combustion engine 11 will be described.
In this process, first, the operation states of the vehicle 10 and the internal combustion engine 11 are read through the detection signals of the various sensors, and it is determined from the operation states whether an automatic stop condition is satisfied. Specifically, for example, it is determined that the automatic stop condition is satisfied when the following conditions (A) to (E) are all satisfied.
(B) The vehicle 10 is stopped.
(B) The internal combustion engine 11 has been warmed up (the cooling water temperature THW is higher than the water temperature lower limit).
(C) The accelerator pedal 21 is not depressed.
(D) The brake pedal 22 is depressed.
(E) After all of the above conditions (A) to (D) are satisfied, there is no history of the automatic stop of the internal combustion engine 11 being executed.

  If any one of the above conditions (A) to (E) is not satisfied, it is assumed that the automatic stop condition is not satisfied and the internal combustion engine 11 is not under the condition for executing the automatic stop. 11 automatic stop is not executed. Thereafter, when the automatic stop condition is satisfied, for example, when the vehicle 10 stops at an intersection, the operation of the internal combustion engine 11 is stopped, for example, the fuel supply to the internal combustion engine 11 is stopped. As described above, in the automatic stop start process, it is determined that the automatic stop condition is satisfied when all the conditions (A) to (E) are satisfied, and the operation of the internal combustion engine 11 is automatically stopped based on this determination. Is done.

Next, a process for restarting the internal combustion engine 11 will be described.
In this process, first, the operation states of the vehicle 10 and the internal combustion engine 11 are read through the detection signals of the various sensors, and it is determined from the operation states whether a restart condition is satisfied. Specifically, under the condition that the internal combustion engine 11 is in an automatically stopped state, the restart condition is satisfied when any one of the above conditions (A) to (D) is not satisfied. It is judged.

  Then, even when the internal combustion engine 11 is not automatically stopped or when the internal combustion engine 11 is automatically stopped, if all of the above conditions (a) to (d) are satisfied, Assuming that the start condition is not satisfied and the condition for restarting the internal combustion engine 11 is not satisfied, the internal combustion engine 11 is not restarted. Thereafter, when any one of the above conditions (A) to (D) is not satisfied in the automatic stop state of the internal combustion engine 11, a process for restarting the internal combustion engine 11 is executed assuming that the restart condition is satisfied. Specifically, the starter motor 20 is driven and cranking of the internal combustion engine 11 is executed, and well-known fuel injection control and ignition timing control are executed, and the internal combustion engine 11 is restarted.

Hereinafter, a starting device for starting the internal combustion engine 11 will be described in detail.
FIG. 2 shows a schematic configuration of the starting device according to the present embodiment.
As shown in FIG. 2, a disc-shaped flywheel 23 is attached to the crankshaft 12 of the internal combustion engine 11. The flywheel 23 is integrally provided with a ring-shaped ring gear 23 a extending along the outer peripheral surface thereof.

  On the other hand, the starter motor 20 is attached in the vicinity of the internal combustion engine 11. The output shaft 24 of the starter motor 20 is provided with a pinion gear 24a. The pinion gear 24a is provided so as to be able to reciprocate in the axial direction of the output shaft 24 (the left-right direction in the figure) and to be rotatable together with the output shaft 24.

  Further, the starter motor 20 is switched to switch between a connected state and a disconnected state between the output shaft 24 (specifically, the pinion gear 24a) of the starter motor 20 and the crankshaft 12 (specifically, the ring gear 23a) of the internal combustion engine 11. A mechanism 25 is provided. The switching mechanism 25 includes an arm 26 for reciprocating the pinion gear 24a and an actuator 27 for operating the arm 26. The actuator 27 is a solenoid drive type that switches between an operating state and a non-operating state by switching between power supply to the built-in electromagnetic solenoid 27a and power supply stop based on an output signal from the electronic control unit 30. Is adopted.

  When the switching mechanism 25 (specifically, the actuator 27) is not operated, the pinion gear 24a is in a position where it does not mesh with the ring gear 23a (position shown in FIG. 2). On the other hand, when the switching mechanism 25 is actuated (specifically, when the plunger 27b of the actuator 27 moves to the left side in FIG. 2), the arm 26 rotates about the fulcrum F. As a result, the pinion gear 24a moves to the ring gear 23a side (right side in FIG. 2) and meshes with the ring gear 23a. At this time, the crankshaft 12 of the internal combustion engine 11 is connected to the output shaft 24 of the starter motor 20. It becomes a state.

  Furthermore, the starter motor 20 is connected to the battery 19 (see FIG. 1) via the power supply switch 28. The power supply switch 28 is a solenoid-driven type that switches between a conductive state and a non-conductive state by switching power supply to the built-in electromagnetic solenoid 28a and power supply stop based on an output signal from the electronic control unit 30. The thing is adopted. When the power supply switch 28 is not operated (during an off operation), the connection between the battery 19 and the starter motor 20 is cut off, and power is not supplied to the starter motor 20. On the other hand, when the power supply switch 28 is activated to be in the on-operation state, the battery 19 and the starter motor 20 are connected and power is supplied to the starter motor 20.

FIG. 3 shows an electric circuit of the starting device according to the present embodiment.
As shown in FIG. 3, the operation switch 37 (specifically, its terminal COM) is connected to the positive electrode of the battery 19. The operation switch 37 includes a stop position that is operated when the internal combustion engine 11 is stopped, a start position that is operated when the internal combustion engine 11 is started, and an operation position that is operated after the internal combustion engine 11 is started. ing.

  When the operation switch 37 is operated to the stop position, the terminal COM of the operation switch 37 is connected to the terminal OFF. Since this terminal OFF is not connected anywhere, at this time, power is not supplied from the battery 19 to each part of the vehicle via the terminal COM. Therefore, when the operation switch 37 is operated to the stop position, the operation of the internal combustion engine 11 is stopped.

  When the operation switch 37 is operated to the start position to start the internal combustion engine 11, the terminal COM of the operation switch 37 is connected to the terminal ST. This terminal ST is connected to the electronic control unit 30 (its power supply terminal). Therefore, at this time, power supply to the electronic control unit 30 is started.

  The terminal ST is connected to an electromagnetic relay 41 (specifically, the winding 41a) for switching the operation / non-operation of the actuator 27 via the diode 40. The contact 41b of the electromagnetic relay 41 has one terminal connected to the positive electrode of the battery 19 and the other terminal connected to the negative electrode of the battery 19 via the variable resistor 42 and the actuator 27 (specifically, the electromagnetic solenoid 27a). It is connected. As the electromagnetic relay 41, a normally open type, a so-called normally open type is employed. Therefore, when the operation switch 37 is operated to the start position, the electromagnetic relay 41 is turned on, and power is supplied to the electromagnetic solenoid 27a of the actuator 27 via the variable resistor 42. As a result, the actuator 27 is operated and the pinion gear 24a and the ring gear 23a are connected.

  Further, the terminal ST is connected to the electromagnetic relay 44 (specifically, the winding 44a) via the delay circuit 43. The contact 44 b of the electromagnetic relay 44 has one terminal connected to the positive electrode of the battery 19 and the other terminal connected to the negative electrode of the battery 19 via the electromagnetic solenoid 28 a of the power supply switch 28. Note that the starter motor 20 and the battery 19 are connected via a contact 28 b of the power supply switch 28. Further, both the electromagnetic relay 44 and the power supply switch 28 are normally open. Therefore, when the operation switch 37 is operated to the start position, the electromagnetic relay 44 is turned on and the power supply switch 28 is turned on, so that power is supplied to the starter motor 20.

  Here, in the present embodiment, the terminal ST of the operation switch 37 and the electromagnetic relay 44 are connected via the delay circuit 43. The delay circuit 43 is composed of a semiconductor integrated circuit such as an IC or a semiconductor element such as a transistor. When the operation switch 37 is operated to the starting position and power is supplied from the battery 19, a little time is passed. After that, power is supplied to the electromagnetic relay 44. Therefore, in the present embodiment, the delay circuit 43 starts supplying power to the starter motor 20 after some time has elapsed after the operation switch 37 is operated to the start position. On the other hand, since such a delay circuit is not provided between the terminal ST of the operation switch 37 and the electromagnetic relay 41, power is supplied to the electromagnetic solenoid 27a in accordance with the operation of the operation switch 37 to the starting position. As a result, the operation of the actuator 27 is started.

  Therefore, in the present embodiment, when the operation switch 37 is operated to the starting position to start the internal combustion engine 11, the operation of the actuator 27 is started first, and after a while, the power supply to the starter motor 20 is started. Be started. As a result, the starter motor 20 is driven after waiting for the ring gear 23a and the pinion gear 24a to be engaged and connected by the operation of the actuator 27, so that the crankshaft 12 of the internal combustion engine 11 can be driven. The auxiliary torque is appropriately applied.

  On the other hand, when the operation of the internal combustion engine 11 is continued after the start of the internal combustion engine 11 is completed, the operation switch 37 is operated to the operation position. At this time, the terminal COM of the operation switch 37 is connected to the terminal IG. This terminal IG is connected to the electronic control unit 30 (its power supply terminal). Therefore, even after the operation switch 37 is operated to the operation position, the power supply to the electronic control unit 30 is continued. At this time, since the connection between the terminal COM and the terminal ST is interrupted, the power supply to the starter motor 20 and the actuator 27 is stopped.

  Further, the electronic control unit 30 does not interpose the operation switch 37 between the winding 41a of the electromagnetic relay 41 and the cathode of the diode 40, or between the winding 44a of the electromagnetic relay 44 and the delay circuit 43. And the variable resistor 42 are connected separately. In the apparatus according to the present embodiment, if power is supplied to the electronic control unit 30, the power supply to the starter motor 20 and the power supply to the actuator 27 (specifically, the electromagnetic solenoid 27a) are separately performed. The configuration is such that it can be executed at different timings based on the command signal.

In the apparatus according to the present embodiment, the operation of the switching mechanism 25 and the drive of the starter motor 20 are executed as follows when the automatic stop / start control is executed.
That is, first, when the automatic stop condition is satisfied and the automatic stop of the internal combustion engine 11 is executed, the electromagnetic relay 41 is sent from the electronic control unit 30 at the timing when the engine speed NE is reduced to a predetermined speed (for example, 300 rpm). When the command signal is output and the electromagnetic relay 41 is turned on, the actuator 27 is activated.

  After that, when the pinion gear 24a and the ring gear 23a are engaged and connected, the output of the command signal from the electronic control unit 30 to the electromagnetic relay 41 is stopped and the electromagnetic relay 41 is turned off. At this time, although the operation of the actuator 27 is stopped, the pinion gear 24a and the ring gear 23a are held in mesh with each other by the frictional resistance acting at the contact portion between the pinion gear 24a and the ring gear 23a. It should be noted that the pinion gear 24a and the ring gear 23a are in a connected state because the operation duration time of the actuator 27 has reached a predetermined time, the moving position of the pinion gear 24a is detected and the moving position is in a connected state. It can be determined by the position indicating Further, the operation of the actuator 27 is not limited to stopping the operation of the actuator 27 when the pinion gear 24a and the ring gear 23a are connected, but the operation of the actuator 27 is continued until the restart or completion of the internal combustion engine 11. May be.

  After that, when the restart condition is satisfied, a command signal is output from the electronic control unit 30 to the electromagnetic relay 44 and the electromagnetic relay 44 is turned on, so that the power supply switch 28 is turned on and the starter motor 20 is turned on. Is started.

  As described above, in the apparatus according to the present embodiment, when the internal combustion engine 11 is automatically stopped, the operation of the internal combustion engine 11 is performed so that the ring gear 23a and the pinion gear 24a are connected prior to the establishment of the restart condition. In the stop process, power supply to the electromagnetic solenoid 27a is started and the switching mechanism 25 is activated. Thereafter, power supply to the starter motor 20 is started on the condition that the restart condition is satisfied.

  Here, if the time required to complete the restart of the internal combustion engine 11 becomes longer, the timing at which the vehicle 10 can start is delayed, which may cause a decrease in the starting performance. Further, in some cases, the occupant may feel slack in the start of the vehicle 10 and the drivability may be lowered. For these reasons, it can be said that it is desirable to complete the restart of the internal combustion engine 11 at an early stage.

  In this regard, in the apparatus according to the present embodiment, the switching mechanism 25 is operated prior to the establishment of the restart condition. Therefore, it is not necessary to operate the switching mechanism 25 when the internal combustion engine 11 is restarted. Therefore, when the internal combustion engine 11 is restarted, the drive of the starter motor 20 can be started early, and the restart can be completed early. Thereby, the fall of the start performance of the vehicle 10 and the fall of drivability come to be suppressed.

  By the way, in the starter according to the present embodiment, prior to restart of the internal combustion engine 11, the output shaft 24 (specifically, the pinion gear 24a) of the starter motor 20 and the crankshaft 12 (specifically, the internal combustion engine 11). When the ring gear 23a) is connected, the pinion gear 24a and the ring gear 23a mesh with each other. Therefore, at this time, it is inevitable that a sound (hereinafter referred to as “meshing sound”) is generated due to the meshing between the pinion gear 24a and the ring gear 23a. There is.

  In particular, in the starter according to the present embodiment, the switching mechanism 25 is used when the internal combustion engine 11 is stopped or stopped, that is, when the sound generated by the engine operation (hereinafter referred to as “background noise”) is small. Since the engagement sound is generated by the operation, it can be said that the engagement sound is conspicuous and is likely to be a noise.

  In view of this point, in this embodiment, the electromagnetic solenoid 27a of the actuator 27 and the battery 19 are connected via the variable resistor 42. Hereinafter, the operation of the variable resistor 42 will be described.

  FIG. 4 shows an example of the transition of the amount of current flowing through the electromagnetic solenoid 27a. In FIG. 4, the solid line indicates the amount of current in the device according to the present embodiment, and the alternate long and short dash line indicates the amount of current in the device of the comparative example in which the variable resistor is not provided.

  As shown in FIG. 4, when a voltage is applied to the electromagnetic solenoid 27a at time t1, a large current (so-called inrush current) flows through the electromagnetic solenoid 27a. Immediately thereafter, the amount of current flowing through the electromagnetic solenoid 27a decreases rapidly, and becomes stable at a constant amount of current after time t2.

  As can be seen from FIG. 4, in the device of the present embodiment (solid line), the current flowing through the electromagnetic solenoid 27a can be kept small compared to the device of the comparative example (dashed line) in which the variable resistor 42 is not provided. It becomes like this. In particular, since the inrush current of the electromagnetic solenoid 27a can be greatly suppressed, the magnetic force generated by the electromagnetic solenoid 27a can be reduced, and the movable part of the switching mechanism 25 (specifically, the plunger 27b of the actuator 27) can be reduced. In addition, the moving speed of the arm 26) and thus the moving speed of the pinion gear 24a can be reduced. Thereby, the meshing sound accompanying meshing with the pinion gear 24a and the ring gear 23a can be suppressed small. Therefore, according to the present embodiment, although the pinion gear 24a and the ring gear 23a mesh with each other in a low background noise state, the meshing sound associated with the meshing can be suppressed, and the switching mechanism 25 operates. The generation of noise due to can be suppressed.

  Here, due to the characteristics of the battery 19, when the remaining amount decreases, the electric power supplied from the battery 19 to the electromagnetic solenoid 27 a may decrease. In this case, since the magnetic force generated by the electromagnetic solenoid 27a becomes small, the moving speed of the movable part of the switching mechanism 25 becomes unnecessarily low. Such a change in the operating characteristics of the switching mechanism 25 due to the change in the remaining amount of the battery 19 is not preferable because it causes instability of the starting function of the internal combustion engine 11.

  In view of this point, in the present embodiment, a resistance value can be changed based on a command signal from the electronic control unit 30 instead of simply providing a resistor between the electromagnetic solenoid 27a of the actuator 27 and the battery 19. A variable resistor 42 is provided. Thereby, the resistance value of the resistor (specifically, the variable resistor 42) provided between the battery 19 and the electromagnetic solenoid 27a is set in accordance with the change in the remaining amount of the battery 19, so that The resistance value can be appropriately set with a high degree of freedom.

The details of the process of setting the resistance value of the variable resistor 42 (resistance value setting process) will be described below with reference to FIG.
FIG. 5 is a flowchart showing an execution procedure of the resistance value setting process, and a series of processes shown in this flowchart is executed by the electronic control unit 30 as an interrupt process at predetermined intervals.

  As shown in FIG. 5, in this process, first, the remaining amount of the battery 19 is read (step S101). The remaining amount of the battery 19 is sequentially estimated and stored by the electronic control unit 30 based on the voltage of the battery 19 at that time.

  Thereafter, a control target value (target resistance value TR) for the resistance value of the variable resistor 42 is calculated based on the remaining amount of the battery 19 (step S102). In the device of the present embodiment, the relationship between the remaining amount of the battery 19 and the resistance value of the variable resistor 42, specifically, the engagement between the pinion gear 24a and the ring gear 23a, while suppressing the generated sound (engagement sound) is reduced. A relationship that can be quickly completed is obtained in advance based on the results of experiments and simulations and stored in the electronic control unit 30. Here, the target resistance value TR is calculated based on the relationship stored in the electronic control unit 30. Specifically, a smaller value is calculated as the target resistance value TR as the remaining amount of the battery 19 is smaller.

Then, after the resistance value of the variable resistor 42 is set so as to satisfy the target resistance value TR (step S103), this process is temporarily ended.
Hereinafter, the setting mode of the resistance value of the variable resistor 42 will be specifically described.

FIG. 6 shows a specific configuration of the variable resistor 42.
As shown in FIG. 6, the variable resistor 42 includes a plurality of resistors R (R1, R2, R3... Rn) and a plurality of switches S (S1, S2, S3... Sn). ing. Specifically, a plurality of resistors in which one resistor (for example, R1) and one switch (for example, S1) are connected in series are provided, and these are connected in parallel. As each switch S, a normally closed type, a so-called normally closed type, is employed. These switches S can be operated individually by the electronic control unit 30. Each switch S may be a normally open type.

  In the apparatus of the present embodiment, it is possible to change the resistance value of the variable resistor 42 in multiple stages by operating each switch S separately to switch the connection mode of each resistor R. Specifically, when only one resistor R is connected, the resistance value of the resistor R itself becomes the resistance value of the variable resistor 42, and when a plurality of resistors R are connected, the resistors R Is the resistance value of the variable resistor 42.

  Then, when setting the resistance value of the variable resistor 42 in the process of step S103 of the resistance value setting process (see FIG. 5), each switch S is individually operated based on the target resistance value TR, and the variable resistor 42 is set. The resistance value is set. Specifically, the resistance value of the variable resistor 42 is set so as to become smaller as the remaining amount of the battery 19 is smaller. For this reason, when the power supplied to the electromagnetic solenoid 27a decreases due to the decrease in the remaining battery 19, the resistance value of the variable resistor 42 is decreased and the supplied power is increased. It becomes possible to suppress a change in the power supplied to the electromagnetic solenoid 27a due to the change, and hence a change in the operating characteristics of the switching mechanism 25. Thereby, instability of the starting function of the internal combustion engine 11 is suppressed.

As described above, according to the present embodiment, the effects described below can be obtained.
(1) The electromagnetic solenoid 27a of the actuator 27 and the battery 19 are connected via the variable resistor 42. For this reason, although the power is supplied to the electromagnetic solenoid 27a and the pinion gear 24a meshes with the ring gear 23a in a situation where background noise is small, such as when the internal combustion engine 11 is stopped or when the engine 11 is stopped, the meshing sound associated with the meshing. Can be kept small, and the generation of noise due to the operation of the switching mechanism 25 can be suppressed.

  (2) The variable resistor 42 is provided between the electromagnetic solenoid 27a and the battery 19, and the resistance value of the variable resistor 42 is variably set. Therefore, the resistance value of the resistor is set such that the resistance value of the resistor (variable resistor 42) provided between the electromagnetic solenoid 27a and the battery 19 is set in accordance with the change in the remaining amount of the battery 19. It becomes possible to set appropriately with a high degree of freedom.

  (3) The smaller the remaining amount of the battery 19, the smaller the resistance value of the variable resistor 42 is set. Therefore, a change in power supplied to the electromagnetic solenoid 27a due to a change in the remaining amount of the battery 19 and, in turn, a change in operating characteristics of the switching mechanism 25 can be suppressed.

  (4) When the operation of the internal combustion engine 11 is automatically stopped or at the time of automatic stop, that is, when the background noise is low, the switching mechanism 25 operates to generate a meshing sound. In an apparatus that is likely to become, the meshing noise can be kept small.

The embodiment described above may be modified as follows.
The estimation method of the remaining amount of the battery 19 is not limited to adopting the estimation method based on the voltage of the battery 19, and any estimation method can be employed. For example, a current sensor for detecting the charge current amount and the discharge current amount of the battery 19 is newly provided and a method of estimating based on a detection signal of the current sensor is adopted, or estimation is performed based on the operating state of the internal combustion engine 11 at that time. Or adopt a method to do.

  The resistance value setting process (FIG. 5) is not limited to being executed as an interrupt process every predetermined period, and can be executed at an arbitrary timing. For example, it can be executed only once under the condition that the automatic stop condition is satisfied, or can be executed only once when the internal combustion engine 11 is normally started.

  -Instead of or variably setting the resistance value of the variable resistor 42 according to the remaining amount of the battery 19, the resistance value of the variable resistor 42 is variably set according to the degree of deterioration of the battery 19. May be. Even when the deterioration of the battery 19 progresses, the power supplied from the battery 19 to the electromagnetic solenoid 27a decreases and the moving speed of the movable part of the switching mechanism 25 becomes the same as when the remaining amount of the battery 19 decreases. May be low. Such a change in the operating characteristics of the switching mechanism 25 due to the deterioration of the battery 19 is also undesirable because it causes instability of the starting function of the internal combustion engine 11. In this regard, according to the above-described configuration, by reducing the resistance value of the variable resistor 42 and increasing the supply power as the supply power to the electromagnetic solenoid 27a decreases because the degree of deterioration of the battery 19 is large, A change in the power supplied to the electromagnetic solenoid 27a due to the deterioration of the battery 19 can be suppressed. Therefore, it is possible to suppress a change in the operating characteristics of the switching mechanism 25 due to the deterioration of the battery 19. Note that the degree of deterioration of the battery 19 can be estimated based on the voltage of the battery 19, the total usage time of the battery 19, the travel distance of the vehicle 10, and the like.

  The resistance value of the variable resistor 42 is set according to the operating state of the switching mechanism 25 instead of, or in addition to, variably setting the resistance value of the variable resistor 42 according to the remaining amount of the battery 19. May be. In this configuration, the resistance value of the variable resistor 42 may be set to a large value over a predetermined period from the start of the operation of the switching mechanism 25, and may be set to a relatively small value after the predetermined period has elapsed. As a result, immediately after the switching mechanism 25 starts to operate, that is, when a meshing sound is generated with the meshing of the pinion gear 24a and the ring gear 23a, the moving speed of the movable part of the switching mechanism 25 is slowed to keep the meshing noise small. be able to. Moreover, when a predetermined period has elapsed since the start of the operation of the switching mechanism 25, that is, when the possibility that the engagement between the pinion gear 24a and the ring gear 23a has progressed to some extent and the meshing noise becomes large, possible portions of the switching mechanism 25 Can be quickly moved to complete the meshing. Thus, according to the above configuration, the meshing between the pinion gear 24a and the ring gear 23a can be completed quickly while suppressing the generated sound (meshing sound).

  In such a configuration, one of the resistors R (R1, R2, R3... Rn) of the variable resistor 42 (FIG. 6) may be omitted. In this case, in a predetermined period after the operation of the switching mechanism 25 is started, electric power is supplied from the battery 19 to the electromagnetic solenoid 27a via the resistor R, so that the movable part of the switching mechanism 25 is moved. The moving speed can be slowed down. In addition, after a predetermined period has elapsed, the electric power is supplied from the battery 19 to the electromagnetic solenoid 27a without sandwiching the resistor R, so that the possible portion of the switching mechanism 25 can be moved quickly. be able to.

  The switch S1 of the variable resistor 42 (FIG. 6) may be omitted, and a circuit structure in which power supply to the electromagnetic solenoid 27a is always performed via the resistor R1. In the same configuration, when the resistance value of the variable resistor 42 is variably set, each switch S (S2, S3... Sn) may be operated separately based on the target resistance value TR.

  The battery 19 and the electromagnetic solenoid 27a are connected via the variable resistor 42 only during the automatic start of the internal combustion engine 11 during normal start (when the operation switch 37 is operated to the start position) and during automatic start. A circuit configuration to be connected may be adopted. In the apparatus according to the above-described embodiment, the operation of the switching mechanism 25 and the drive of the starter motor 20 at the normal start of the internal combustion engine 11 are performed as a series of operations based on a common operation (operation to the start position of the operation switch 37). Executed. Therefore, it is highly likely that the meshing sound is recognized as a sound generated with a series of operations for starting the engine, such as a cranking operation, and the possibility of noise is low. According to the above configuration, at the time of normal starting of the internal combustion engine 11 where such a meshing sound is unlikely to be noise, the switching mechanism 25 can be operated quickly to improve the starting performance. In addition, at the time of automatic start of the internal combustion engine 11 where the meshing noise is likely to be noise, the operating speed of the switching mechanism 25 can be suppressed to a low level and the meshing sound can be suppressed to a low level.

  FIG. 7 shows an example of such an electric circuit. Note that FIG. 7 omits a circuit for supplying power to the starter motor 20 (see FIG. 3), and shows only a circuit for supplying power to the electromagnetic solenoid 27a of the actuator 27. In the electric circuit shown in FIG. 7, the contact 41b of the electromagnetic relay 41 that is operated by operating the operation switch 37 to the starting position (terminal ST) is directly connected to the electromagnetic solenoid 27a without interposing the variable resistor 42 therebetween. Yes. Further, an electromagnetic relay 50 that is operated by an output from the electronic control unit 30 is newly provided. The electromagnetic relay 50 has one contact 50b connected to the positive electrode of the battery 19 and the other connected to a portion between the contact 41b of the electromagnetic relay 41 and the electromagnetic solenoid 27a via the variable resistor 42. Yes. In this electric circuit, when the operation switch 37 is operated to the start position, the electromagnetic relay 41 is turned on, and the battery 19 and the electromagnetic solenoid 27a are connected without interposing the variable resistor 42 therebetween. On the other hand, when the internal combustion engine 11 is restarted, the electromagnetic relay 50 is turned on by the power supply to the winding 50a of the electromagnetic relay 50 by the electronic control unit 30, and the battery 19 and the electromagnetic solenoid 27a are connected to the variable resistor. 42 is connected.

  In place of the variable resistor 42, a resistor having a constant resistance value may be provided. Also with such a configuration, it is possible to suppress the meshing noise by suppressing the inrush current of the electromagnetic solenoid 27a, and it is possible to suppress the generation of noise due to the operation of the switching mechanism 25.

  The operation condition of the switching mechanism 25 can be arbitrarily changed as long as it is a timing after the automatic stop condition is satisfied and the operation of the switching mechanism 25 is started at a timing prior to the establishment of the restart condition. .

  The starter according to the above embodiment can be applied to a starter in which the automatic stop start control is not executed after the configuration is appropriately changed. For the purpose of completing the normal start of the internal combustion engine 11 at an early stage, the following configuration may be employed. That is, when the internal combustion engine is stopped or stopped so that the pinion gear and the ring gear are connected prior to the operation of the operation switch to the start position for supplying power to the electromagnetic solenoid of the actuator for operating the switching mechanism. On the other hand, the power supply to the starter motor is started on the condition that the operation switch is operated to the start position. According to the above configuration, in such a starting device, the meshing sound between the pinion gear and the ring gear can be suppressed to be small, and the generation of noise due to the operation of the switching mechanism can be suppressed.

  DESCRIPTION OF SYMBOLS 10 ... Vehicle, 11 ... Internal combustion engine, 12 ... Crankshaft (engine output shaft), 13 ... Transmission, 14 ... Drive shaft, 15 ... Differential gear, 16 ... Axle, 17 ... Wheel, 18 ... Alternator, 19 ... Battery, 20 ... starter motor, 21 ... accelerator pedal, 22 ... brake pedal, 23 ... flywheel, 23a ... ring gear (second gear), 24 ... output shaft, 24a ... pinion gear (first gear), 25 ... switching mechanism, 26 ... arm, 27 ... actuator, 27a ... electromagnetic solenoid (drive solenoid), 27b ... plunger, 28 ... power supply switch, 28a ... electromagnetic solenoid, 28b ... contact, 30 ... electronic control unit (control unit, setting means and estimation) Means), 31 ... crank sensor, 32 ... accelerator sensor, 33 ... temperature sensor, 34 ... 35, speed sensor, 36 ... voltage sensor, 37 ... operation switch, 40 ... diode, 41, 44, 50 ... electromagnetic relay, 41a, 44a, 50a ... winding, 41b, 44b, 50b ... contact, 42 ... variable Resistor, 43 ... delay circuit.

Claims (5)

A solenoid-driven switching mechanism that switches between a connected state and a disconnected state between a first gear provided on the output shaft of the starter motor and a second gear provided on the engine output shaft, and the starter motor and the switching mechanism For supplying power to the drive solenoid, and a control unit for executing power supply to the starter motor and power supply to the drive solenoid at different timings based on different command signals The control unit supplies power to the drive solenoid in the process of stopping or at the time of stopping the engine so that the first gear and the second gear are connected prior to establishment of the engine start condition. And starting the power supply to the starter motor on condition that the engine start condition is satisfied,
A starting device for an internal combustion engine, wherein the driving solenoid and the battery are connected via a resistor. The starter for an internal combustion engine according to claim 1, further comprising setting means for variably setting a resistance value of the resistor. The internal combustion engine starter according to claim 2,
The starting device further includes an estimating means for estimating the remaining amount of the battery,
The starting device for an internal combustion engine, wherein the setting means sets a smaller value as the resistance value when the remaining amount estimated by the estimating means is smaller. The starter for an internal combustion engine according to any one of claims 1 to 3,
The starter is applied to an engine system that automatically stops the internal combustion engine when a stop condition is satisfied, and executes automatic stop start control that automatically starts the internal combustion engine when the restart condition is satisfied. An internal combustion engine starting device. The starting device for an internal combustion engine according to claim 4,
The internal combustion engine starter characterized in that the controller starts power supply to the drive solenoid when the stop condition is satisfied and the engine rotational speed is reduced to a predetermined speed or less. .

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