JP4209754B2 - Ignition device for internal combustion engine - Google Patents

Description

  The present invention relates to an ignition device used for an internal combustion engine such as an automobile engine, and more particularly to an internal combustion engine ignition device provided with a protection means that automatically shuts off energization when an abnormality occurs.

  Conventionally, as described in, for example, Patent Document 1, an electronic control device that outputs an ignition signal, and an ignition unit that includes a switching element that controls energization / cutoff of a primary current based on the ignition signal from the electronic control device, An ignition coil for generating a high voltage on the secondary side by energization / shut-off control of the primary current by the switching element, current limiting means for limiting the primary current flowing in the ignition coil provided in the ignition means, abnormal energization or abnormal heat generation An ignition device for an internal combustion engine has already been proposed that includes a protection means for limiting the primary current flowing through the ignition coil by detecting the above.

JP-A-8-335522

  According to the conventional technology, the energization is restricted (the energization is stopped or the primary current is reduced) by the protection means against abnormal energization or abnormal heat generation, and the ignition means including switching prevention can be protected. I don't know if the energization was restricted. Therefore, for example, in the case of an ignition device for an automobile, the vehicle may be returned and collected from the market due to a warning in the vehicle due to misfire or the like. However, the ignition means recovered due to the control abnormality is treated as an unknown cause despite the fact that the protection means is activated and the energization is limited and the abnormality is not an abnormality as a part, and the essence of the abnormality remains unimproved. A case occurs.

  An object of the present invention is to provide an ignition device for an internal combustion engine that can detect that a protection means is operated due to an external factor such as a control abnormality or a failure of an ignition coil.

  In order to achieve the above object, the present invention provides an ignition device for an internal combustion engine having a protective means for detecting abnormal energization or abnormal heat generation and limiting a primary current flowing through an ignition coil, and outputs an output based on the operation of the protective means. The memory means for storing the signal to be transmitted is provided.

  As described above, by providing the storage means for storing the signal output based on the operation of the protection means, when energization is restricted, the energization restriction is performed by reading the signal stored in the storage means. Therefore, it is possible to determine whether the operation is due to the operation of the protection means by abnormality control without abnormality or the operation of the protection means due to an external factor other than the ignition means, and the essence of the abnormality can be confirmed.

  As described above, according to the present invention, it is possible to obtain an internal combustion engine ignition device that can detect that the protection means has been activated due to abnormal control or other external factors.

  A first embodiment of an internal combustion engine ignition device according to the present invention will be described below with reference to FIG.

  The internal combustion engine ignition device according to the present embodiment includes an electronic control device 1 that outputs an ignition signal a, and ignition means 2 that controls energization / cutoff of the primary current b based on the ignition signal a from the electronic control device 1. The ignition means 2 includes an ignition coil 3 that generates intermittent high voltage on the secondary side by energization / cutoff control of the primary current b by the ignition means 2, and the high voltage of the ignition coil 3 is supplied to the ignition plug 4. Repeat the discharge.

  The output of the electronic control unit 1 is composed of a PNP transistor 5, an NPN transistor 6, and a resistor 7, and the PNP transistor 5 and the NPN transistor 6 are turned on and off at an appropriate ignition timing calculated by the arithmetic unit 8. The ignition signal a is output to the ignition means 2.

  The ignition means 2 includes a switching element 9 such as a power transistor or an insulated gate bipolar transistor, a current detection resistor 10, a current limiting circuit 11 for limiting a primary current flowing through the ignition coil 3, an input resistor 12, and an abnormality. A self-shutoff circuit 13 which is a protection means for detecting an abnormal energization by control and limiting a primary current flowing through the ignition coil 3 (stopping energization or reducing a primary current), and a switching element during operation of the self-shutoff circuit 13 MOSFET 4 for extracting the gate voltage of 9, and the switching element 9 starts energization when the ignition signal a output from the electronic control device 1 is low → high, and the switching element 9 energizes when it is high → low. By shutting off, a voltage is generated at the collector of the switching element 9. Due to this voltage, a high voltage corresponding to the turn ratio is induced on the secondary side of the ignition coil 3 and discharged by the spark plug 4.

  The ignition coil 3 has a primary coil 3A and a secondary coil 3B to which a battery voltage Vb is applied, and a pre-prevention high-voltage diode 15 between the secondary coil 3B and the ignition plug 4.

  Although the above configuration is almost the same as that of the conventional ignition device, in the present embodiment, a collector voltage detector 16 is further connected to the collector side of the switching element 9, and an ignition signal a from the electronic control device 1 is connected. A comparison unit 17 that compares the output signal c from the collector voltage detection unit 16, a reset circuit unit 20 that extracts the charge charged in the capacitor 18 based on the ignition signal a through the NPN transistor 19, and a comparison unit 17 And an output unit 22 that continues output for a predetermined time by a capacitor 18 and a resistor 21 based on the output signal d from

  Further, in order to form the reference voltage and output voltage of each part from the battery voltage Vb, resistors 23 and 24 and Zener diodes 25 and 26 are connected between the battery (not shown) and the collector voltage detector 16 and between the battery and the output part 22. Connected between.

  Furthermore, the output unit 22 is connected to a storage means 27 for storing the output signal e to be output. The storage means 27 is provided with an information transfer terminal 28 and connected to a personal computer 29 for storage means. The information stored in 27 is read out. In order to display that the output signal e is input to the storage means 27, for example, a display 30 such as a display lamp that is turned on when the output signal e is input may be provided.

  The storage means 27 is installed independently of the electronic control device 1 and the ignition means 2, but may be unitized with the electronic control device 1 as indicated by a two-dot chain line.

  Since it comprised as mentioned above, when the ignition signal a is continuously input into the ignition means 2 by the abnormal control of the electronic control apparatus 1, for example, since the ignition means 2 flows the primary current b continuously, switching element 9 causes abnormal heat generation. For this purpose, the self-shutoff circuit 13 operates to stop energization of the ignition coil 3. However, when an abnormal control occurs, it is not determined whether the energization stop to the ignition coil 3 is due to the operation of the self-shutoff circuit 13, in other words, the part is recovered without knowing the cause. .

  According to this embodiment, the operation of the self-shutoff circuit 13 is confirmed by the personal computer 29 or the display 30 after the event occurs by storing the output signal e from the output unit 22 in the storage means 27. Therefore, the cause of the abnormality can be identified, and the essence of the abnormality can be confirmed.

  When the self shut-off circuit 13 is a thermal shut-off circuit, the energization can be cut off by detecting abnormal heat generation of the switching element 9. However, when the self-shutoff circuit 13 is a timer-type shutoff circuit, the self-shutoff circuit 13 functions and can stop energization when the ignition signal a exceeding the set energization time is input. If the ignition signal a within the energization time and not less than the specified value is continuously input to the switching element 9, the energization cannot be stopped, and the switching element 9 may be abnormally heated.

  Accordingly, in the abnormal energization control, regardless of the thermal type or the timer type, when the self-shutoff circuit 13 operates, the self-shutoff circuit 13 is reset simultaneously with the ignition signal a being off.

  By doing so, the switching element 9 can be prevented from being destroyed. However, abnormal energization causes failure of the ignition coil 3 or misalignment of the ignition timing, leading to insufficient combustion or misfire of the internal combustion engine, and abnormal overheating of the harmful exhaust removal catalyst. Etc. may occur.

  In such a case, for example, when the output from the output unit 22 or the output from the self-shutoff circuit 13 is confirmed by the arithmetic unit 8 to be equal to or higher than a specified value, an alarm is given or fuel injection is performed. By performing control such as issuing a fuel injection stop command to the apparatus, abnormal overheating of the catalyst can be avoided and secondary failure can be prevented in advance.

  Next, the normal operation during which the ignition signal a within the specified energization time is input from the electronic control unit 1 to the ignition means 2 and the self-shutoff circuit 13 does not operate will be described with reference to FIG.

  When the ignition signal a is input to the gate portion of the switching element 9 and the switching element 9 is turned on, the collector voltage v of the switching element 9 is pulled to a voltage required for each current value of the switching element 9. Based on this collector voltage, the collector voltage detector 16 that monitors the energization time of the ignition means 2 detects the operation of the switching element 9 and outputs an output signal c to the comparator 17. The comparison unit 17 compares the energization time of the ignition signal a and the output time of the output signal c of the collector voltage v. If “the energization time of the ignition signal a = the output time of the output signal c”, the comparison unit 17 The output signal d is not output from the output unit 22 and, of course, the output signal e from the output unit 22 is not generated.

  Next, the case where the self-shutoff circuit 13 is operated by the abnormality control will be described.

  When the energization time of the ignition signal a from the electronic control device 1 is the ignition signal al (FIG. 2) exceeding the specified time, the self-shutoff circuit 13 operates to force the switching element 9 when the specified time is exceeded. Turn off.

  At this time, the relationship between the output time of the collector voltage detection output c and the energization time of the ignition signal al is “the energization time of the ignition signal al> the output time of the collector voltage detection output c”. The signal d is output and input to the output unit 22. When the output unit 22 receives the shut-off signal d, the output unit 22 generates an output signal e and inputs the output signal e to the storage unit 27. Receiving the output signal e, the storage means 27 turns on the display 30 and stores it.

  The user or maintenance personnel confirms that the display 30 is turned on, and if the display 30 is not present, the personal computer 29 is connected to the storage means 27 after the energization is stopped. It is possible to determine that the current is abnormally energized, and to confirm the nature of the abnormality.

  In addition, an ignition signal exceeding a specified value may be continuously input to the ignition means 2 due to abnormal control of the electronic control device 1 or other external factors.

  In such a case, the next ignition signal an (FIG. 2) is input to the ignition means 2, and at the same time, the charge charged in the capacitor 18 by the reset circuit unit 20 is extracted based on the ignition signal an, and the output unit 22 The reset signal f for turning off the continuous output signal e from is output. Thereby, even when the self-shutoff circuit 13 operates continuously, the output signal e can be output to the storage means 27 each time.

  Next, a second embodiment of the internal combustion engine ignition device according to the present invention will be described with reference to FIG.

  3 is different from FIG. 1 in that the ignition signal a from the electronic control unit 1 is input to the ignition means 2 via the resistors 31 and 32, and further from the comparison unit 17 instead of the output unit 22 in FIG. The output signal d is output to the storage means 25 via the latch circuit 33 and the resistor 34. In addition, the collector voltage detection unit 16, the comparison unit 17, the reset circuit unit 20, the latch circuit 33, and the circuit configuration of the ignition unit 2 are integrated into a monolithic silicon substrate so that the one-chip type ignition unit 2 is compact. And can be built in the ignition coil 3.

  FIG. 4 shows a third embodiment of an internal combustion engine ignition device according to the present invention.

  This embodiment is the same as the second embodiment shown in FIG. 3 except that the circuit power supply operates on the basis of the ignition signal a from the electronic control unit 1 and that the one-chip type ignition means 2 is the same. It is. However, the collector voltage detection unit 16, the comparison unit 17, the reset circuit unit 20, and the latch circuit 33 shown in FIG. 3 are directly input to the storage unit 27 from the self-shutoff circuit 13 as a signal that the self-shutoff circuit 13 has operated. Accordingly, the number of terminals can be reduced, and further miniaturization becomes possible. Reference numerals 36 and 37 in FIG. 4 are resistors.

  As described above, according to each embodiment, since the operation of the self-shutoff circuit 13 that protects the switching element 9 can be monitored by the storage unit 27, the energization stop of the electronic control device 1 is stopped. It can be confirmed whether the control is abnormal or due to other external factors, and as a result, the essence of the abnormality can be confirmed and improved.

  Further, by making the ignition means 2 into one chip, it is possible to reduce the size and to incorporate the ignition coil 3, so that the occupied volume as the internal combustion engine is not increased.

The block diagram which shows 1st Embodiment of the ignition device for internal combustion engines by this invention. The timing chart figure which shows the operation | movement of the ignition device for internal combustion engines of FIG. The block diagram which shows 2nd Embodiment of the ignition device for internal combustion engines by this invention. The block diagram which shows 3rd Embodiment of the ignition device for internal combustion engines by this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Electronic control device, 2 ... Ignition means, 3 ... Ignition coil, 4 ... Spark plug, 9 ... Switching element, 11 ... Current limiting circuit, 13 ... Self shut-off circuit, 16 ... Collector voltage detection part, 17 ... Comparison part , 20... Reset circuit unit, 22... Output unit, 27.

Claims (4)

An electronic control device that outputs an ignition signal, ignition means including a switching element that controls energization / interruption of the primary current based on the ignition signal from the electronic control device, and primary current energization / interruption control by the switching element An ignition coil that generates a high voltage on the secondary side, a current limiting unit that is provided in the ignition unit and limits a primary current that flows through the ignition coil, and a primary current that flows through the ignition coil by detecting abnormal energization or abnormal heat generation in an internal combustion engine ignition apparatus that includes a protection means for limiting to, Rutotomoni provided storage means for storing a signal based on the operation of the protection means, the information exchange terminal to read the information stored to the personal computer in the storage means ignition device for an internal combustion engine, characterized by comprising. A power transistor or an insulated gate bipolar transistor that controls energization / cutoff of the primary current according to an ignition signal output from the electronic control device, and the power transistor or insulated gate bipolar transistor performs energization / cutoff control of the primary current. An ignition coil that generates a high voltage on the secondary side, a current limiting circuit that limits a primary current that flows through the ignition coil, and a self-shutoff circuit that detects abnormal energization or abnormal heat generation and limits the primary current that flows through the ignition coil In the internal combustion engine ignition device comprising: a storage means for storing a signal based on the operation of the self-shutoff circuit; and an information transfer terminal for reading information stored in the personal computer is provided in the storage means. An ignition device for an internal combustion engine. 3. The internal combustion engine according to claim 2, wherein the signal based on the operation of the self-shutoff circuit is obtained by comparing an ignition signal from the electronic control device with a collector voltage of the power transistor or the insulated gate bipolar transistor. Engine ignition device. The signal based on the operation of the self-shutoff circuit is configured to compare the width of the ignition signal and the on period of the collector voltage, and output a signal when the on period of the collector voltage is smaller than the width of the ignition signal. The ignition device for an internal combustion engine according to claim 3 .

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