JP5331752B2 - Control device for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a start-up controller and a control method for an internal combustion engine capable of preventing trouble such as damage and reduction of a holding force from being generated caused by overheat of a solenoid 7 for pushing out a pinion 8, in a system of engaging the pinion 8 of a starter with a ring gear 9 and for starting up quietly the engine in a short time. <P>SOLUTION: The problem to be solved is solved by an electric motor having a connection means for connection with the internal combustion engine, and a start-up device for the internal combustion engine having a stop means for stopping the internal combustion engine when a prescribed stop condition is satisfied, and for indicating the connection with the internal combustion engine to the connection means, and the controller for the internal combustion engine for operating the electric motor to start up the internal combustion engine, when a connection command to the connection means is continued for a prescribed time or more. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a control device for an internal combustion engine using an electric motor, and relates to start control.

  For example, in Patent Document 1, when an automatic stop of the engine rotation is detected, an ON signal is sent from the controller to the starter pinion engagement solenoid of the starter to engage the pinion with the ring gear while the engine is stopped. When the condition is established, the starter motor is energized to automatically start the engine, thereby improving durability and reducing noise.

Japanese Patent Laid-Open No. 11-030139

  However, in the above-described prior art, when the solenoid for controlling the pinion engagement of the starter is energized, the solenoid may overheat, the holding power decreases, and further, the engine restart failure due to the remaining battery level may become a problem.

  An object of the present invention is to provide a start control device and a control method for an internal combustion engine that realizes control of a solenoid that meshes with a starter pinion in advance without causing the above problem.

  An object of the present invention is to provide an internal combustion engine having an electric motor having connection means for connecting to the internal combustion engine and a stop means for stopping the internal combustion engine when a predetermined stop condition is satisfied, and instructing the connection means to connect to the internal combustion engine. When the connection instruction to the starter and the connection means continues for a predetermined time or more, the motor is operated to start the internal combustion engine.

  More preferably, the determination value of the next connection instruction time is increased in proportion to the connection release time.

  More preferably, during the connection, the determination value of the next connection instruction time is decreased.

  Further, the above-described problem is an internal combustion engine having an electric motor having connection means for connecting to the internal combustion engine and stop means for stopping the internal combustion engine when a predetermined stop condition is satisfied, and instructing the connection means to connect to the internal combustion engine. The engine starting device and the internal combustion engine have means for injecting and igniting fuel to the cylinder, and determining the motion state of the internal combustion engine and stopping the operation of the electric motor based on the determination result. .

Further, the above problem is that when the starting condition is satisfied, the electric motor is rotated, and the rotational speed of the internal combustion engine reaches a first predetermined value at which the internal combustion engine can be started without the assist force of the electric motor. This is also achieved by stopping the rotation and releasing the connection between the connection means and the internal combustion engine when a second predetermined value, which is the complete explosion speed of the internal combustion engine, is greater than the first predetermined value. Is done.

  Further, the above-described problem is an internal combustion engine having an electric motor having connection means for connecting to the internal combustion engine and stop means for stopping the internal combustion engine when a predetermined stop condition is satisfied, and instructing the connection means to connect to the internal combustion engine. This is also achieved by instructing connection to the connecting means after the engine starter and the fuel supply to the internal combustion engine are shut off and before the internal combustion engine stops.

  Further, the above-described problem is an internal combustion engine having an electric motor having connection means for connecting to the internal combustion engine and stop means for stopping the internal combustion engine when a predetermined stop condition is satisfied, and instructing the connection means to connect to the internal combustion engine. The engine starting device and the connecting means have means for switching the driving force of the connection to a plurality, and this can also be achieved by connecting the connecting means with a small driving force after the internal combustion engine is stopped.

  Further, the above-described problem is an internal combustion engine having an electric motor having connection means for connecting to the internal combustion engine and stop means for stopping the internal combustion engine when a predetermined stop condition is satisfied, and instructing the connection means to connect to the internal combustion engine. This can also be achieved by connecting the engine starting device and the connection means after the internal combustion engine is stopped, and driving the electric motor to bring the piston of the internal combustion engine to a predetermined position.

  Further, the above-described problem is an internal combustion engine having an electric motor having connection means for connecting to the internal combustion engine and stop means for stopping the internal combustion engine when a predetermined stop condition is satisfied, and instructing the connection means to connect to the internal combustion engine. In the engine starting device, this is also achieved by prohibiting the driving of the electric motor for a predetermined time after driving the connecting means.

  According to the present invention, it is possible to avoid the problem caused by energizing the starter pinion meshing solenoid of the starter in advance during idle stop, and to start the internal combustion engine that meshes the pinion with the ring gear while the engine is stopped. In addition, there is an effect that a control method can be provided.

The block diagram which shows an example of the control apparatus (ECU) of an internal combustion engine. The time chart which shows operation of a pinion and a motor at the time of idle stop and starting. The table | surface which shows the operation pattern of the pinion and the motor at the time of idle stop and start. Scheduled processing that starts every 10 milliseconds. The detailed flow of idle stop control (step 101). The detailed flow of an engine stop process (step 113). The detailed flow of an engine operation process (step 114).

  Next, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a block diagram showing an example of an internal combustion engine start control device (ECU) that is mounted on a vehicle and controls an engine (internal combustion engine) and a starter. In FIG. 1, an ECU 1 includes an input circuit 2, a microcomputer 3 for calculating engine and starter control targets based on such information, and a drive circuit 4 including FETs.

  The input signal is a sensor signal including an engine start switch 5, a brake switch 6, an accelerator and a rotation sensor. The output signal includes a starter system and an engine system.

  The starter pushes out the pinion 8 by the solenoid 7 and is engaged with the ring gear 9 of the engine to be coupled to the engine in advance. In order to reduce the collision noise between the pinion 8 and the ring gear 9 and the temperature rise of the solenoid 7, a relay 11 for weakly coupling with a resistor is provided in addition to the relay 10 for coupling strongly. Further, the motor 12 for turning the engine is provided with a relay 14 for slowly turning it with a resistor in addition to the relay 13 for starting the engine in order to make the piston stop position optimal for restarting.

  The engine includes a throttle for changing the air amount, an injector for changing the fuel injection amount, a plug for changing the combustion timing, and the like.

  The ECU 1 is connected to other control devices such as the transmission control device 15 by CAN communication and receives vehicle speed information and the like.

FIG. 2 is a time chart showing the operation of the pinion 8 and the motor 12 at the time of idling stop and engine start, and FIG. 3 is a table showing an operation pattern, and the operation will be described using them.

  When the start switch 5 is turned on, the relay 10 of the pinion 8 is turned on to engage the pinion 8 (connection, d), and after 70 milliseconds, the relay 13 of the motor 12 is turned on and the engine is turned (assist, e). When the rotational speed N2 at which the engine can start without reaching the assisting force of the motor 12 is reached, the relay 13 of the motor 12 is turned off (waiting for complete explosion, f). The relay 10 is turned off (assist end, g).

  When the brake pedal is depressed and the vehicle speed becomes 0 and 1 second has elapsed, the fuel supply to the engine is cut to stop idling (engine stop, a). When the engine speed drops to N1, the relay 11 of the pinion 8 is turned off. Turns on and bites the pinion 8 with a small impact (pre-connection, b). Thereafter, when the brake pedal is released, in preparation for running, the relay 10 of the pinion 8 and the relay 13 of the motor 12 are turned on and the engine is restarted by the same procedure as when the start switch 5 is turned on.

  When the engine is stopped and the piston stop position is not optimal for restarting, the relay 10 of the pinion 8 and the relay 14 of the motor 12 are turned on for a time corresponding to the deviation amount and the engine is turned ( Alignment, c) Correct the piston position.

  As a condition for restarting the engine, in addition to releasing the brake pedal, the timer for measuring the remaining energized time provided for heat generation protection of the solenoid 7 may become zero. This timer is decreased at regular intervals while the solenoid 7 is energized, and is increased at regular intervals while the energization is stopped.

  The operation of FIG. 2 is realized by incorporating the program of the flowcharts of FIGS. 4 to 7 into the microcomputer 3.

  FIG. 4 shows a scheduled process that starts every 10 milliseconds. In step 100, the sensor signal including the start switch 5, the brake switch 6 and the accelerator is captured. In step 101, the idle stop control detailed in FIG. 5 is performed.

  Based on the information acquired in step 100, the throttle opening is adjusted in step 102 to optimally control the amount of air, in step 103, the fuel injection amount in the injector injection time, in step 104, the plug ignition timing, and the like.

  In step 105, information transmission / reception such as reception of vehicle speed information from the transmission control device 15 is performed by CAN communication.

  FIG. 5 is a detailed flow of idle stop control (step 101). In step 110, it is determined whether the protection timer of the solenoid 7 has become 0. If false, it is determined in step 111 whether the brake switch 6 is on. If true, the vehicle speed is 0 (stopped) in step 112. ) Determine if 1 second has passed. If true, the mode selection process related to the engine stop described in FIG. 6 is performed in step 113, and if false, the mode selection process related to the engine operation described in FIG. 7 is performed in step 114. In step 115, the starter pinion 8 and the motor 12 are controlled via those relays in accordance with the mode determined in step 113 or step 114.

  FIG. 6 is a detailed flow of the engine stop process (step 113). In step 120, it is determined whether the engine speed is lower than a predetermined value N1. If true, it is determined whether the engine is not stopped or the piston stop position is the optimum position for restart. If false, the process proceeds to step 122 and the alignment (c) in FIG. 3 is performed. If true, the process proceeds to step 123 and the pre-connection (b) in FIG. 3 is selected. If step 120 is false, the process proceeds to step 124 and the engine stop (a) in FIG. 3 is selected.

  FIG. 7 is a detailed flow of the engine operation process (step 114). In step 130, it is determined whether 0.1 second has elapsed after the solenoid 7 of the pinion 8 has been energized. If false, it is determined whether the engine speed is lower than a predetermined value N3 higher than the predetermined value N2. In the case of false, it is determined that the engine has been reliably started, and the process proceeds to step 133, and the assist end (g) in FIG. 3 is selected. In the case of true, the process proceeds to step 134 and waiting for the complete explosion in FIG. If true in step 131, the process proceeds to step 135 and assist (e) in FIG. 3 is selected. If false in step 130, the process proceeds to step 136 and connection (d) in FIG. 3 is selected.

  In step 110, it is determined whether the remaining time of the protection timer of the solenoid 7 has become 0. In step 114, the engine can be operated to protect the solenoid 7 from overheating.

  Although the idle stop time is shortened and the fuel efficiency effect is impaired, it is possible to prevent the exhaust performance from deteriorating due to the decrease in the catalyst temperature due to the idle stop.

  The present invention can be applied to a start control device for an internal combustion engine in which a pinion meshes with a ring gear while the engine is stopped.

1 ECU
2 Input circuit 3 Microcomputer 4 Drive circuit 5 Engine start switch 6 Brake switch 7 Solenoid 8 Pinion 9 Ring gear 10, 11, 13, 14 Relay 12 Motor 15 Transmission control device

Claims (4)

A start control device for connecting the connecting means provided in the electric motor to the internal combustion engine after the fuel supply to the internal combustion engine is interrupted and before the start condition is satisfied, and starting the internal combustion engine by rotating the electric motor after the start condition is satisfied In
After the start condition is satisfied, the motor is rotated to stop the rotation of the electric motor when the rotational speed of the internal combustion engine reaches a first predetermined value at which the internal combustion engine can be started even without the assist force of the motor. A start control device for releasing the connection between the connecting means and the internal combustion engine when a second predetermined value , which is the complete explosion speed of the internal combustion engine, is greater than the first predetermined value. .   The connecting means has means for switching the driving force of the connection to a plurality, and makes the driving force when connecting the connecting means and the internal combustion engine smaller than the driving force when rotating the internal combustion engine with the electric motor. The start control device according to claim 1. 3. The start control device according to claim 1, wherein , after the connection means is connected to the internal combustion engine, the electric motor is driven to bring the piston of the internal combustion engine to a predetermined position. 4. The start control device according to claim 1, wherein after the connecting means is connected to the internal combustion engine, driving of the electric motor is prohibited for a predetermined time.

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