JP2015155658A - engine control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an engine control system which can enhance the reliability of idling stop control while simplifying a circuit constitution.

SOLUTION: An engine control system comprises: a detection circuit 40 which detects opening/closing states of opening/closing parts 41 to 43 arranged at a vehicle body; and an idling stop ECU20 which includes a detection result of the detection circuit as at least either of a prescribed automatic stop condition and a prescribed restart condition, and performs an automatic stop and a restart of an engine 10 on the basis of the adaptability of the automatic stop condition and the restart condition. The detection circuit 40 has a plurality of switches 44 to 46 which are arranged at a plurality of the opening/closing parts 41 to 43, respectively, and connected to one another in series or in parallel by signal lines L2, L3, and a pull-up resistor 52 which is arranged at a side of an output end of a series circuit of a plurality of the switches 44 to 46, and pulls up an output end voltage.

COPYRIGHT: (C)2015,JPO&INPIT

Description

  The present invention relates to an engine control system applied to a vehicle that automatically stops and restarts an engine by idling stop control.

  Engine idling stop control for automatically stopping and restarting an engine based on whether or not a predetermined idling stop condition is satisfied has been put into practical use. By performing the idling stop control, the fuel efficiency of the engine can be improved. On the other hand, the state in which the engine is automatically stopped by the idling stop control is similar to the stop state of the engine in which the ignition is turned off. For this reason, there is a possibility that a problem may occur due to the opening / closing part of the vehicle such as the hood of the vehicle being opened for inspection or the like in a state where the engine is automatically stopped by the idling stop control.

  Therefore, in Patent Document 1, an ECU (ISS-ECU) that controls an idling stop is provided based on a signal from the switch by providing a switch that detects an open / closed state of an open / close unit such as a hood provided on the vehicle body. The state is determined, and it is determined whether or not the idling stop control is performed. That is, the idling stop control is allowed to be performed when each of the opening / closing parts is closed, and the idling stop control is rejected when some of the opening / closing parts are open.

JP 2012-122459 A

  By the way, a vehicle body may be provided with a plurality of opening / closing parts. At this time, in order to determine whether or not to perform idling stop control, providing a circuit configuration such as a switch or a signal line for each opening / closing unit leads to disadvantages such as complicating the circuit configuration and increasing costs. .

  It is a technical object of the present invention to provide an engine control system that can improve the idling stop control reliability while simplifying the circuit configuration.

  The present invention includes a detection circuit that detects the open / closed state of the open / close section provided in the vehicle body, and the detection result of the detection circuit as at least one of a predetermined automatic stop condition and a predetermined restart condition. And an idling stop control means for automatically stopping and restarting the engine based on the success or failure of the restart condition, and the detection circuit is provided in each of the plurality of open / close sections and is connected to each other in series or in parallel by a signal line And a voltage adjusting unit that is provided on the output end side of the series circuit or the parallel circuit of the plurality of detection units and that pulls up or pulls down the output terminal voltage.

  In the above invention, since the plurality of detection units in the detection circuit are connected to each other in series or in parallel by signal lines, the opening / closing of the plurality of opening / closing units can be detected collectively, and the configuration can be simplified regarding the detection of opening / closing of the opening / closing units. Can be planned. In this case, assuming the implementation of the idling stop control, if any one of the plurality of opening / closing parts is open, the automatic stop or restart should be stopped, and the opening / closing of each opening / closing part is detected. Even if the necessity of this is taken into consideration, suitable opening / closing detection can be performed.

The schematic block diagram of the vehicle system by which an engine control system is mounted. Schematic of the example of arrangement | positioning of an opening / closing part. The circuit diagram of the detection circuit which detects the opening / closing state of an opening / closing part. Explanatory drawing of the specific example of the relationship between the state of a detection circuit, and a voltage. The flowchart of an idling stop process. The circuit diagram of the detection circuit of the modification example.

  Hereinafter, an embodiment embodied in a vehicle that uses an engine as a travel drive source and performs idling stop control will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of an engine control system mounted on a vehicle.

  In FIG. 1, an engine control system includes an engine (internal combustion engine) 10, a chargeable / dischargeable battery 11, a starter (motor) 12, an alternator (generator) 13, and an auxiliary machine 14 that is an in-vehicle various electrical equipment (accessories), An ignition switch (hereinafter referred to as IG switch 16) that opens and closes by the driver's ignition key operation, a relay 22, an engine ECU 30, an idling stop ECU (hereinafter referred to as ISS-ECU 20), and the like are provided.

  The engine 10 injects fuel and adds a mixture of fuel and air in a combustion chamber to burn the mixture. A starter 12 is connected to a crankshaft (not shown) of the engine 10. At the same time, an alternator 13 is connected through connecting means such as a belt.

  The battery 11 which is a secondary battery is a lead storage battery of 12 to 14 V, for example, and supplies power to the engine ECU 30 and the ISS-ECU 20 in addition to the starter 12 and the auxiliary machine 14.

  The starter 12 is driven when the IG switch 16 is turned on and when the engine 10 automatically stopped by the idling stop control is restarted. The starter 12 is connected to the battery 11 via a relay 22.

  The alternator 13 generates power with the rotation of the engine 10 and supplies the generated power to the battery 11 and the auxiliary machine 14. The auxiliary machine 14 is driven by receiving power supply from the alternator 13 and the battery 11.

  The IG switch 16 is for switching the power supply state of the vehicle, and can be switched to an off position, an ignition (IG) position, and a start position by rotating an ignition key (not shown).

  When the IG switch 16 is in the off position, power supply from the battery 11 to each device is stopped. When the IG switch 16 is in the IG position, power is supplied to the engine ECU 30 and various on-vehicle devices. When the IG switch 16 is in the start position, the relay 22 is energized, power is supplied from the battery 11 to the starter 12, and cranking of the engine 10 by the starter 12 starts.

  When the IG switch 16 is at the IG position or the start position, a signal indicating that the starter 12 is being driven is transmitted from the IG switch 16 to the engine ECU 30 and the ISS-ECU 20.

  The engine ECU 30 is mainly configured by a microcomputer including a central processing unit (CPU), a storage device (ROM and RAM), a non-volatile flash memory, and the like, and receives signals from various sensors that detect the driving state of the vehicle. It takes in and controls the operating state of the engine 10. For example, in addition to the vehicle speed sensor 19 that detects the vehicle speed, the shift position sensor 18 that detects the position of the shift lever, the brake sensor 21 that detects the depression of the brake, a water temperature sensor for detecting the cooling water temperature of the engine 10, a crank angle Captures signals from sensors, accelerator sensors, etc. And the control program etc. which were memorize | stored in ROM etc. are performed and the driving | running state of the engine 10 is controlled. For example, fuel injection amount control, ignition timing control, and the like are controlled.

  The engine ECU 30 is connected to the ISS-ECU 20 via the signal line L1, and is configured to transmit information to each other by bidirectional communication with the ISS-ECU 20. Thereby, detection signals from various sensors acquired by the engine ECU 30 are also input to the ISS-ECU 20 via the signal line L1.

  The ISS-ECU 20 is mainly configured by a microcomputer including a central processing unit (CPU), a storage device (ROM and RAM), a nonvolatile flash memory, and the like. The ISS-ECU 20 stops the combustion of the engine 10 and automatically stops the engine 10 when a predetermined automatic stop condition is satisfied based on the detection signal of the driving state of the vehicle acquired by the engine ECU 30. In addition, after the automatic stop of the engine 10, when a predetermined automatic restart condition is satisfied, the drive of the starter 12 and the combustion of the engine 10 are resumed.

  Further, the ISS-ECU 20 takes in information on the open / closed states of a plurality of open / close portions provided at the respective housing locations in the vehicle body of the various actuators driven by the engine operation, and automatically stops or restarts the engine 10 by idling stop control. It is determined whether or not to implement. That is, when all of the plurality of opening / closing parts are closed, it is determined that automatic stop by idling stop control is performed, and when any of the plurality of opening / closing parts is open, automatic stop by idling stop control is performed. It is determined not to implement. Further, when any of the plurality of opening / closing parts is in an open state while the engine 10 is automatically stopped, it is determined that the restart of the engine 10 is not permitted (implemented).

  FIG. 2 shows a schematic diagram of an arrangement example of a plurality of opening / closing sections provided on the vehicle body. FIG. 3 shows a circuit diagram of a detection circuit for detecting the open / closed state of a plurality of open / close sections. In the example of FIG. 2, an opening / closing door is provided as the opening / closing part 41 in the housing part S <b> 1 in which the cooling fan 23 of the radiator is housed. In addition, a seat as an opening / closing part 42 is provided in a housing part S2 (engine room) of the engine 10 provided under the seat in the vehicle interior. Furthermore, an opening / closing door is provided as the opening / closing portion 43 in the housing portion S3 (battery housing portion) of the battery 11 provided in the luggage compartment of the vehicle body. Each of the open / close sections 41 to 43 is provided with switches 44 to 46 as detection sections for detecting the open / close state.

  In FIG. 3, the detection circuit 40 includes switches 44 to 46 provided in the open / close units 41 to 43, signal lines L <b> 2 and L <b> 3 connecting the switches 44 to 46, a voltage dividing resistor 51, and a pull-up resistor 52. And an output terminal 48 for outputting a signal of the detection circuit 40 to the ISS-ECU 20.

  Specifically, the switch 44 and the switch 45 are connected via the signal line L2, and the switch 45 and the switch 46 are connected via the signal line L3. Thereby, each switch 44-46 is connected in series. The other end of the switch 44 is connected to the ground (for example, vehicle body ground) via the voltage dividing resistor 51. The other end of the switch 46 is connected to the output terminal 48, and the output terminal 48 is connected to the ISS-ECU 20. A node 46 a between the switch 46 and the output terminal 48 is connected to the constant voltage Vcc via the pull-up resistor 52. The constant voltage Vcc is obtained by stepping down the voltage of the battery 11 to a predetermined voltage (for example, 5 V) by a DC / DC converter.

  The switches 44 to 46 are turned on (conductive) when the open / close sections 41 to 43 are closed, and are turned off (non-conductive) when the open / close portions 41 to 43 are open. Therefore, the detection circuit 40 becomes conductive when all the switches 44 to 46 are on, and becomes nonconductive when any of the switches 44 to 46 is off.

  The output terminal 48 outputs a different voltage V depending on the state of the detection circuit 40. That is, when the detection circuit 40 is in a conductive state, the first voltage V1 = Vcc × R1 / (R1 + R2) determined by the constant voltage Vcc, the resistor R1 of the voltage dividing resistor 51, and the resistor R2 of the pull-up resistor 52 is output. . When the detection circuit 40 is non-conductive, the second voltage V2 (= Vcc) determined by the constant voltage Vcc and the resistor R2 is output. Note that the first voltage V1 is not equal to the second voltage V2.

  Thereby, the ISS-ECU 20 can determine whether or not to permit the automatic stop and restart of the engine 10 according to the state of the detection circuit 40 acquired based on the voltage V of the output terminal 48. That is, when the detection circuit 40 is in a conductive state and the output terminal 48 is at the first voltage V1, it is determined that automatic stop and restart by idling stop control are permitted. When the detection circuit 40 is non-conductive and the voltage V at the output terminal 48 is the second voltage V2, it is determined that automatic stop and restart by idling stop control are not permitted.

  By the way, in the detection circuit 40, it is assumed that abnormalities occur such as the signal lines L2 and L3 being disconnected or the circuit being short-circuited. In this case, the voltage level of the detection circuit 40 (the voltage V of the output terminal 48) becomes unstable, and it may not be possible to appropriately determine whether or not the automatic stop is required by the idling stop control.

  Therefore, in the present embodiment, by providing the detection circuit 40 with the pull-up resistor 52, the voltage V of the output terminal 48 when an abnormality such as a disconnection or a short circuit occurs in the detection circuit 40 is defined. That is, when the detection circuit 40 is disconnected, the voltage V at the output terminal 48 is pulled up by the pull-up resistor 52 to the second voltage V2, and a short circuit (ground fault) occurs in the detection circuit 40. The voltage V of the output terminal 48 is the ground voltage (third voltage V3). That is, when an abnormality occurs in the detection circuit 40, the voltage V output from the output terminal 48 is determined according to the abnormality state.

  In this case, the ISS-ECU 20 determines whether to perform idling stop control according to the voltage V of the output terminal 48. That is, when the voltage V is the first voltage V1, it is determined that the idling stop control is permitted, and when the voltage V of the output terminal 48 is the second voltage V2 or the third voltage V3, the idling stop control is not permitted. judge. As a result, idling stop control is permitted only when all of the open / close portions 41 to 43 are closed and the detection circuit 40 is normal, and as a result, the reliability of the idling stop control can be improved. .

  FIG. 4 is an explanatory diagram showing the relationship between each state of the detection circuit 40 and the voltage V of the output terminal 48. In FIG. 4, the resistance R1 of the voltage dividing resistor 51 in the detection circuit 40 is 1 kΩ, the resistance R2 of the pull-up resistor 52 is 4 kΩ, the constant voltage Vcc is 5 V, the first voltage V1 is 1 V at the output terminal 48, the second voltage is 2 In the example, the voltage V2 = 5V and the third voltage V3 = 0V. In FIG. 4, “1” indicates that the switches 44 to 46 are in a conductive state, and “0” indicates that the switches 44 to 46 are in a nonconductive state.

  When the detection circuit 40 is normal, the first voltage V1 = 1V is output from the output terminal 48 if all the open / close parts 41 to 43 are closed (if all the switches 44 to 46 are conductive). The Further, if any of the opening / closing parts 41 to 43 is in an open state, the second voltage V2 is output from the output terminal 48. On the other hand, when a disconnection or a power fault has occurred in the detection circuit 40, the second voltage V2 = 5V is output from the output terminal 48 regardless of the open / close state of the open / close sections 41 to 43. On the other hand, when a ground fault abnormality occurs in the detection circuit 40, the third voltage V3 = 0 is output from the output terminal 48 regardless of the open / closed state of the open / close sections 41 to 43.

  That is, the first voltage V <b> 1 is output from the output terminal 48 only when the detection circuit 40 is normal and all the opening / closing parts 41 to 43 are closed. In this case, when the voltage V of the output terminal 48 is the first voltage V1 (1V), the ISS-ECU 20 permits any one of the opening / closing parts 41 to 43 by permitting automatic stop and restart by idling stop control. Implementation of idling stop control when the open state or the detection circuit 40 is abnormal is avoided.

  Next, idling stop processing in the engine control system having the above configuration will be described. FIG. 5 is a flowchart of the idling stop process.

  In FIG. 5, it is determined in step S11 whether or not the engine 10 is in an operating state. For example, when the rotation speed of the crankshaft by the crank angle sensor is equal to or higher than a predetermined value, it is determined that the engine 10 is in an operating state.

  If an affirmative determination is made, the process proceeds to step S12, and whether the brake operation by the brake sensor 21 is detected and the vehicle speed is less than a predetermined value (less than 10 km / h) are satisfied as automatic stop conditions. Determine.

  When an affirmative determination is made, the process proceeds to step S13, and whether or not the detection voltage (voltage V of the output terminal 48) by the detection circuit 40 is the first voltage V1 indicating that all the open / close parts 41 to 43 are closed. Determine whether. If both steps S12 and S13 are positively determined, the engine 10 is automatically stopped on the assumption that the automatic stop condition is satisfied.

  On the other hand, if a negative determination is made in step S13, that is, if the voltage V of the output terminal 48 is the second voltage V2 or the third voltage V3, the present process is terminated without performing the automatic stop of the engine 10.

  On the other hand, if a negative determination is made in step S11, the process proceeds to step S15 to determine whether or not the engine 10 is automatically stopped. If an affirmative determination is made, the process proceeds to step S16 to determine whether or not a restart condition is satisfied. For example, it is determined based on a signal from the brake sensor 21 whether or not the brake is released. When an affirmative determination is made, the process proceeds to step S17 to determine whether or not the voltage V of the detection circuit 40 is the first voltage V1. If both steps S16 and S17 are positively determined, it is determined that the automatic restart condition is satisfied, and the process proceeds to step S18, where the engine 10 is automatically restarted. On the other hand, when a negative determination is made in step S17, that is, when the voltage V of the output terminal 48 is the second voltage V2 or the third voltage V3, the present process is terminated without restarting the engine 10. In addition, this process is complete | finished also when negative determination is carried out by step S12, S13, S15-S17.

  According to the above, the following excellent effects are exhibited.

  (1) In the detection circuit 40, since the plurality of switches 44 to 46 are connected in series by the signal lines L2 and L3, the opening and closing of the plurality of opening and closing parts 41 to 43 can be detected collectively, and the opening and closing parts 41 to 43 can be detected. The configuration can be simplified with respect to detection of opening and closing. In this case, assuming the implementation of the idling stop control, if any one of the plurality of opening / closing parts 41 to 43 is in an open state, the automatic stop or restart should be stopped. Even considering the necessity of detecting the opening / closing of 43, suitable opening / closing detection can be performed.

  (2) It is possible to prevent the engine 10 from being automatically stopped or restarted when a disconnection or a power fault occurs in the detection circuit 40, and the idling stop control can be appropriately performed.

  (3) Since the output voltage is made different for each of when the plurality of opening / closing parts 41 to 43 are fully closed, at least one is opened, and when there is a ground fault, the idling stop control can be appropriately performed. It is also possible to detect a ground fault.

  The present invention is not limited to the description of the above embodiment, and may be implemented as follows.

  -In the above, compared with the configuration in which a detection circuit is provided for each switch, the switches 44 to 46 are connected in series, and the voltage at one end of the series circuit is detected, so that the open / close states of the plurality of open / close sections 41 to 43 are changed. The configuration of the detection circuit 40 for detection is simplified. In addition to this, a plurality of switches are connected in parallel via a comparator, and a pull-up resistor 52 is connected between the output terminal of the comparator and the constant voltage Vcc, so that a plurality of open / close sections 41 to 43 are connected to the vehicle. The configuration of the detection circuit 40 in the case where is provided can be simplified.

  A sensor may be provided in each of the open / close sections 41 to 43 instead of the switches 44 to 46 described above. In this case, simplification of the configuration in the case where a plurality of opening / closing sections are provided in the vehicle can be realized by connecting the sensors in series or connecting them in parallel with a comparator.

  The detection circuit 40 may be a pull-down circuit. For example, the node 46a in FIG. 3 is connected to the ground side, and the voltage dividing resistor 51 is connected to the constant voltage side. In this case, the voltage V of the output terminal 48 when the disconnection or the like occurs in the detection circuit 40 becomes the third voltage V3.

  -Among automatic stop conditions and restart conditions, it may be included in the condition that all open / close parts 41 to 43 are closed only in the automatic stop condition, and all open / close parts 41 to 43 are closed only in the restart condition. May be included in the conditions.

  The detection circuit 40 has a voltage (state) different from the normal time when there is no abnormality when any of the plurality of opening / closing parts is in an open state or when there is an abnormality in the detection circuit 40. The ISS-ECU 20 only needs to determine that idling stop control is not permitted when a voltage (state) different from the normal voltage V (state) is detected.

  For example, as shown in the circuit diagram of the detection circuit 40 of the modified example of FIG. 6, in the configuration of the detection circuit 40 of FIG. 3, the first comparator 61 and the second comparator 62 are provided between the node 46a and the output terminal 48. A parallel connection is provided. For example, the first comparator becomes a high level when the voltage V is less than 4.5V, and becomes a low level when the voltage V is 4.5V or more. The second comparator 62 is at a high level when the voltage V is 0.5 V or higher, and is at a low level when the voltage V is less than 0.5 V. Similar to the above, the second voltage V2 = 5V and the third voltage V3 = 0V at the time of abnormality are set. That is, both the first comparator 61 and the second comparator 62 are at a high level when normal, and either the first comparator 61 and the second comparator 62 are at a low level when abnormal. In this case, the ISS-ECU 20 determines that the idling stop control is permitted when both the first comparator 61 and the second comparator 62 input through the output terminal 48 are at a high level, and the first comparator 61 When either of the second comparators 62 is at the low level, it can be determined that the idling stop control is not permitted.

  DESCRIPTION OF SYMBOLS 10 ... Engine, 11 ... Battery, 40 ... Detection circuit, 41 ... Opening / closing part, 42 ... Opening / closing part, 43 ... Opening / closing part, 44 ... Switch, 45 ... Switch, 46 ... Switch, 52 ... Pull-up resistor, ECU ... Idling stop .

Claims (5)

A detection circuit (40) for detecting an open / closed state of the open / close sections (41-43) provided in the vehicle body;
The detection result of the detection circuit is included as at least one of a predetermined automatic stop condition and a predetermined restart condition, and the engine (10) is automatically stopped and restarted based on the success or failure of the automatic stop condition and the restart condition. An idling stop control means (20) to be implemented;
With
The detection circuit includes:
A plurality of detection units (44 to 46) provided in each of the plurality of opening and closing units and connected to each other in series or in parallel by signal lines;
Voltage adjusting means (52) provided on the output end side of the series circuit or parallel circuit of the plurality of detection units, and pulling up or pulling down the output end voltage;
An engine control system comprising:   The voltage adjusting means of the detection circuit includes at least one of an output terminal voltage when at least one of the plurality of opening / closing parts is in an open state, a disconnection of the signal line constituting the series circuit or the parallel circuit, and a power supply fault. The engine control system according to claim 1, wherein the same output voltage is used when an error occurs.   The voltage adjusting means of the detection circuit outputs a first voltage V1 when the plurality of opening / closing parts are all closed, and a second voltage V2 (≠ when at least one of the plurality of opening / closing parts is open. 3. The third voltage V <b> 3 (≠ V <b> 1, V <b> 2) is output when a ground fault occurs in the signal line constituting the series circuit or the parallel circuit. Engine control system.   The engine control system according to any one of claims 1 to 3, wherein the voltage adjusting means includes a resistor (52).   The engine control according to any one of claims 1 to 4, wherein the opening / closing section is provided at least in an engine housing section (S1) in which the engine is housed and a battery housing section (S2) in which a battery is housed. system.

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