JP2009127498A - Ignition controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ignition controller capable of preventing a transistor for a misfire from being turned on even if a leak current is generated, certainly transmitting an ignition timing signal to a trigger, and permitting an ignition plug to be surely ignited at ignition timing. <P>SOLUTION: The ignition controller comprises a magnet generator 2, a controller body 3, a pickup coil 4, and an ignition coil 5. The magnet generator is equipped with a charging coil 6. The controller body 3 is equipped with a misfire control circuit 11 comprising a capacitor 8, a first resistor member 12 and the transistor 13 for the misfire. One end of the first resistor member 12 is connected with a front side of the capacitor 8 in a charging path 14. Among both ends of the charging coil 6, one end is connected with the charging path 14 while the other end is connected with an internal power supply path 17 in the controller. A second resistor member 28 whose one end is grounded is connected with the internal power supply path 17. The second resistor member 28 has resistance lower than that of the first resistor member 12. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an ignition control device for performing ignition control of an internal combustion engine.

  FIG. 3 is a schematic diagram of a conventional ignition control device.

  As illustrated, the conventional ignition control device 51 includes a magnet generator 52, a control device main body 53, a pickup coil 54, and an ignition coil 55. The magnet generator 52 is provided with a charging coil 56. A protrusion 57 for detecting an ignition timing signal using a pickup coil 54 is provided on the outer periphery of the rotor of the magnet generator 52.

  The control device main body 53 includes a capacitor 58 charged with power supplied from the charging coil 56, a trigger 59 for discharging the ignition coil 55 from the capacitor 58, and a trigger 59 based on a signal from the pickup coil 54. An ignition signal forming circuit 60 for turning on the ignition signal, and a misfire control circuit 61 connected between the ignition signal forming circuit 60 and the trigger 59. The misfire control circuit 61 includes a first resistance member 62 and a misfire transistor 63.

  One end of the first resistance member 62 is connected further to the front side than the diode 65 provided on the front side of the capacitor 58 in the charging path 64 from the magnet generator 52. That is, a charging path 64 is formed from the charging coil 56 in the magnet generator 52 toward the capacitor 58, and the misfire control circuit 61, the diode 65, and the capacitor 58 are formed in the charging path 64 as viewed from the charging coil 56. Each member is connected in this order.

  Both ends of the charging coil 56 are connected to input terminals 71 and 72 of the control device main body 53, respectively, and one end supplies power to the charging path 64 and the other end supplies power to each circuit in the control device main body 53. Is connected to an internal power supply path 67 leading to a power supply circuit 66. The charging path 64 and the internal power supply path 67 are respectively connected to both ends of a short circuit 68 provided in the control device main body 53.

  An external switch misfire control circuit 69 is connected to the charging path 64. The external switch misfire control circuit 69 is connected to the switch 70 and forcibly misfires when the switch 70 is turned on. This switch 70 can be manually operated by the user.

  When ignition control is performed using the ignition control device 51, the operation is as follows.

  The magnet generator 52 is rotated to charge the capacitor 58 from the charging coil 56 via the charging path 64. This charging is performed by positive power generation of the magnet generator 52. Positive power generation refers to power generation when the sine wave output to the input terminal 71 is positive, that is, when the voltage at the input terminal 71 is positive. Therefore, the input terminal 71 becomes a positive power supply input terminal (hereinafter referred to as BR terminal). On the other hand, when the voltage at the input terminal 72 is positive, that is, when the voltage at the input terminal 71 is negative, power generation is negative side power generation. Therefore, the input terminal 72 is a negative side power input terminal (hereinafter referred to as GW terminal). It becomes). The electric power obtained by the negative power generation is supplied to the power supply circuit 66 through the internal power supply path 67 and used in each circuit in the control device main body 53.

  During negative power generation, depending on the potential of the GW terminal 72, the withstand voltage of each circuit in the power supply circuit 66 or the control device main body 53 may be exceeded, resulting in problems with these components. In order to avoid this, the short circuit 68 is turned on when the potential of the GW terminal 72 becomes high. The short circuit 68 includes a thyristor 76 and a Zener diode 77. When the voltage at the GW terminal 72 exceeds the Zener voltage of the Zener diode 77, the thyristor 76 is turned on, and the voltage at the GW terminal 72 is made lower than the Zener voltage to protect the power supply circuit 66 and the like. That is, the short circuit 68 serves as a protection circuit for these.

  Simultaneously with the charging of the capacitor 58 described above, the pickup coil 54 detects the protrusion 57 formed on the rotor of the magnet generator 52 and outputs the rotation of the rotor of the magnet generator 52 to the control device main body 53 as a waveform. The waveform from the pickup coil 54 indicates that when the crankshaft (not shown) of the internal combustion engine is rotating at a low speed, the trigger 59 is turned on at each ignition timing by the output from the ignition signal forming circuit 60, the capacitor 58 is discharged, and the ignition is performed. The voltage on the primary side of the coil 55 is changed and transmitted to the secondary side. Thus, ignition is performed by an ignition plug (not shown) of the internal combustion engine.

  When the magnet generator 52 is reversed, if it is ignited, a problem arises that it causes a ketchin. In order to prevent this, in the case of reverse rotation, the misfire transistor 63 is turned on by the BR terminal voltage, the signal from the ignition signal forming circuit 60 flows to the misfire control circuit 61, and the trigger 59 is not turned on. For this reason, when the magnet generator 52 is reversed, it is possible not to ignite (misfire) and to prevent ketting.

  When the crankshaft (not shown) of the internal combustion engine rotates at a high speed, the trigger 59 is turned on at each ignition timing by the advance angle signal forming circuit 75 earlier than the output from the ignition signal forming circuit 60.

  As described above, the ignition control device 51 charges the capacitor 58 by the positive power generation of the magnet generator 52, supplies power to the control device main body 53 by the negative power generation, determines the ignition timing by the pickup coil 54, and determines the ignition timing. The capacitor 58 is discharged and ignited for each signal.

  FIG. 4 is a time chart when ignition control is performed using a conventional ignition control device. In the following description, the reference numerals in FIG.

  As shown in the figure, positive power generation indicates the region a in the figure, and negative power generation indicates the region b in the figure. The time zone in which the voltages at both terminals 71 and 72 are not so high is a high state where no power is generated (region c in the figure). The pulsar from the projection 57 is input from the negative power generation to this replacement area. The ignition timing is when the pulsar input is present (when there is a protruding signal on the lower side of the figure).

  In the switching time zone, neither the BR terminal 71 nor the GW terminal 72 is in an unstable state because the potential is not determined. At this time, current tends to flow from the capacitor 58 toward the BR terminal. At this time, leakage current flows from the diode 65, but does not flow toward the BR terminal 71 where the potential is not fixed, and passes through the first resistance member 62. The misfire transistor 63 is turned on. Although the leakage current is as small as about 79 μA, for example, the resistance value of the first resistance member 62 is as large as several hundred kΩ (for example, 200 kΩ), so that the misfire transistor 63 is turned on even with a slight leakage current. can do. Therefore, the ignition timing signal is sent to the misfire transistor 63 of the misfire control circuit 61 and is not sent to the trigger 59, and the trigger 59 is not turned on regardless of the ignition timing. For this reason, since the misfire transistor 63 is turned on at the timing to be ignited (area d in the figure) and the ignition signal is masked (in the figure, the ignition signal is indicated by a one-dot chain line), ignition is impossible.

  On the other hand, Patent Literature 1 describes an ignition control circuit. This ignition control device reliably turns off a thyristor for controlling charging and discharging of an ignition capacitor. However, in Patent Document 1, there is no concept of positive-side power generation or negative-side power generation, and no consideration is given to leakage current.

Japanese Patent Laid-Open No. 10-47217

  The present invention takes the above-described prior art into consideration, and prevents the misfire transistor from being turned on even when a leakage current occurs. Therefore, the ignition timing signal is reliably sent to the trigger, and the ignition timing is reliably set. An object of the present invention is to provide an ignition control device that can be ignited with a spark plug.

  In order to achieve the above object, according to the first aspect of the present invention, a magnet generator, a control device main body, a pickup coil, and an ignition coil are provided. The magnet generator includes a charging coil, and the magnet generator A protrusion for detecting an ignition timing signal by the pickup coil is provided on the outer periphery of the rotor of the machine, and in the control device main body, a capacitor charged with electric power supplied from the charging coil, and the capacitor A trigger for discharging from the ignition coil to the ignition coil, an ignition signal forming circuit for turning on the trigger by an ignition timing signal from the pickup coil, and a misfire connected between the ignition signal forming circuit and the trigger Control circuit, and the misfire control circuit includes a first resistance member and a misfire transistor. One end of the first resistance member is connected to a further front side of a diode provided on the front side of the capacitor in a charging path from the magnet generator to the capacitor, and the charging coil includes: Both ends are connected to the control device main body, and one end portion is connected to the charging path, and the other end portion is connected to a power supply circuit for supplying power to each circuit in the control device main body. The charging path and the internal power supply path are connected to both ends of a short circuit provided in the control device body, respectively, and a second resistance member having one end grounded is connected to the internal power supply path, A resistance value of the second resistance member is lower than a resistance value of the first resistance member.

  According to a second aspect of the present invention, the resistance value of the second resistance member is 1 to 9 kΩ, and the resistance value of the first resistance member is 100 to 900 kΩ.

  According to the first aspect of the present invention, since the second resistance member whose one end is grounded is connected to the internal power supply path, a path through which a leakage current from the capacitor flows is formed. That is, by connecting the second resistance member, the potential of the GW terminal, which is a connection portion between the charging coil and the control device body in the internal power supply path, is determined, and the connection between the charging coil and the control device body in the charging path is established. The potential of the BR terminal as a part is also determined. As a result, a discharge path that is grounded from the capacitor through the diode, the BR terminal, the charging coil, the GW terminal, and the second resistance member is formed. Furthermore, since the resistance value of the second resistance member is lower than the resistance value of the first resistance member, the leakage current passes through this discharge path. By this discharge path, the leakage current is divided into a path that flows through the first resistance member to the misfire transistor and the discharge path. For this reason, the current flowing through the misfire transistor can be lowered below the threshold value for turning on the misfire transistor. Therefore, misfire control is not performed due to leakage current, and reliable ignition control can be performed.

  According to the invention of claim 2, since the resistance value of the second resistance member is 1 to 9 kΩ and the resistance value of the first resistance member is 100 to 900 kΩ, the leakage current easily flows to the second resistance member, and the GW terminal The voltage becomes smaller. Accordingly, it is possible to more reliably suppress misfire control due to leakage current and perform accurate ignition control.

  The present invention relates to an ignition control device in which a second resistance member having one end grounded is connected to an internal power supply path, a leakage current discharge path is formed to cause a shunt, and an ignition timing signal can be reliably sent to a trigger. It is.

  FIG. 1 is a schematic diagram of an ignition control device according to the present invention.

  As shown, the basic configuration of the ignition control device 1 is the same as that shown in FIG. That is, the ignition control device 1 includes a magnet generator 2, a control device body 3, a pickup coil 4, and an ignition coil 5. The magnet generator 2 is provided with a charging coil 6. On the outer periphery of the rotor of the magnet generator 2, a protrusion 7 for detecting an ignition timing signal using the pickup coil 4 is provided.

  The control device body 3 includes a capacitor 8 charged with power supplied from the charging coil 6, a trigger 9 for discharging the ignition coil 5 from the capacitor 8, and a trigger 9 based on a signal from the pickup coil 4. Is provided with an ignition signal forming circuit 10 for turning on and a misfire control circuit 11 connected between the ignition signal forming circuit 10 and the trigger 9. The misfire control circuit 11 includes a first resistance member 12 and a misfire transistor 13. The capacitor 8 is charged during the positive power generation described above.

  One end of the first resistance member 12 is connected further to the front side than the diode 15 provided on the front side of the capacitor 8 in the charging path 14 from the magnet generator 2. That is, a charging path 14 is formed from the charging coil 6 in the magnet generator 2 toward the capacitor 8, and the misfire control circuit 11, the diode 15, and the capacitor 8 are connected to the charging path 14 as viewed from the charging coil 6. Each member is arranged in the order of. The other end of the first resistance member 12 is connected to the base side of the misfire transistor 13.

  Both ends of the charging coil 6 are respectively connected to the input terminals 21 and 22 of the control device main body 3, and one end supplies power to the charging path 14 and the other end supplies power to each circuit in the control device main body 3. Is connected to an internal power supply path 17 that leads to a power supply circuit 16. The power supply circuit 16 is provided with a capacitor (not shown), and the capacitor is charged during the negative power generation described above. The charging path 14 and the internal power supply path 17 are respectively connected to both ends of a short circuit 18 provided in the control device body 3. The short circuit 18 includes a thyristor 26 and a Zener diode 27.

  An external switch misfire control circuit 19 is connected to the charging path 14. The external switch misfire control circuit 19 is connected to the switch 20 and forcibly misfires when the switch 20 is turned on. The switch 20 can be manually operated by the user.

  The pickup coil 4 detects a protrusion 7 formed on the outer periphery of the rotor of the magnet generator 2, and the waveform from the pickup coil 4 is an ignition signal forming circuit 10 when the crankshaft (not shown) of the internal combustion engine is rotating at a low speed. When the crankshaft is rotating at high speed, the trigger 9 is turned on at each ignition timing by the output from the advance angle signal forming circuit 25, the capacitor 8 is discharged, and the voltage on the primary side of the ignition coil 5 is Change it and tell it to the secondary side. Thereby, it is ignited by a spark plug (not shown) of the internal combustion engine.

  The ignition control using the ignition control device 1 as described above is the same as the conventional ignition control described above, but one end is grounded to the internal power supply path 17 of the ignition control device 1 according to the present invention. The second resistance member 28 is connected. By forming the second resistance member 28 in the internal power supply path 17, a discharge path for leakage current can be formed, and the potentials of the BR terminal 21 and the GW terminal 22 are determined. The first resistance member 12 is about several hundred kΩ (100 to 900 kΩ), whereas the second resistance member 28 is about several kΩ (1 to 9 kΩ).

  That is, since the second resistance member 28 whose one end is grounded is connected to the internal power supply path 17, a path through which leakage current from the capacitor 8 flows is formed. By connecting the second resistance member 28, the potential of the GW terminal 22, which is a connection portion between the charging coil 6 and the control device main body 3 in the internal power supply path 17, is determined. The potential of the BR terminal 21 that is a connection portion between the coil 6 and the control device main body 3 is also determined. As a result, there is no floating state where the potential is not fixed between the BR terminal 21 and the GW terminal 22, and the diode 15, the BR terminal 21, the charging coil 6, the GW terminal 22, and the second resistance member 28 from the capacitor 8. A discharge path that is grounded is formed. Furthermore, since the resistance value of the second resistance member 28 is lower than the resistance value of the first resistance member 11, the leakage current surely passes through this discharge path. By this discharge path, the leakage current is divided into a path through the first resistance member 12 to the misfire transistor 13 and the discharge path. Therefore, the current flowing through the misfire transistor 13 can be lowered below the threshold value for turning on the misfire transistor 13. Therefore, misfire control is not performed due to leakage current, and reliable ignition control can be performed.

  In addition, since the resistance value of the second resistance member 28 is 1 to 9 kΩ and the resistance value of the first resistance member 12 is 100 to 900 kΩ, leakage current easily flows to the second resistance member, and the voltage at the GW terminal is reduced. . Accordingly, it is possible to more reliably suppress misfire control due to leakage current and perform accurate ignition control. Note that the applicant of the present application, when the leakage current is 79 μA, the resistance value of the first resistance member 11 is 200 kΩ, the resistance value of the second resistance member 28 is 9 kΩ (the resistance value of the second resistance member 28 is the first resistance In the case of about 1/22 of the resistance value of the member 11, it is confirmed that a shunt occurs and the misfire transistor 13 is not turned on.

  FIG. 2 is a time chart when ignition control is performed using the ignition control device according to the present invention. In the following description, the reference numerals in FIG.

  As shown in the figure, positive power generation is performed in a region where the voltage at the BR terminal 21 is high (the upper side in the diagram is high) (region a in the diagram), and negative power generation is a region where the voltage at the GW terminal 22 is high (region a). The voltage is high on the upper side of the figure) (region b in the figure). The region where the voltages at both terminals 21 and 22 protrude and are not high is a state where both are not generating power and are switched (region c in the figure). The pulser from the protrusion 7 is input to this replacement area. The ignition timing is when the pulsar input is present (when there is a protruding signal on the lower side of the figure).

  Therefore, it is necessary to reliably ignite the above-mentioned replacement region (region c) in the ignition timing. Conventionally, a leakage current from the capacitor 8 flows to the misfire control circuit 11, turns on the misfire transistor 13, and the ignition signal is not sent to the trigger 9, and the trigger 9 is not turned on regardless of the ignition timing. It was happening. However, since the second resistance member 28 is provided, the leakage current also flows in the direction of the second resistance member 28, so that the leakage current is distributed in both directions of the misfire control circuit 11 and the second resistance member 28. Therefore, since the value of the current flowing through the misfire control circuit 11 can be lowered below the threshold value of the current at which the misfire transistor 13 is turned on, the misfire transistor 13 is not turned on during the replacement time period. For this reason, the ignition signal input in this time zone is reliably sent to the trigger 9, and the capacitor 8 can be discharged. Thereby, reliable ignition becomes possible.

1 is a schematic view of an ignition control device according to the present invention. It is a time chart figure when ignition control is performed using the ignition control apparatus which concerns on this invention. It is the schematic of the conventional ignition control apparatus. It is a time chart figure when ignition control is performed using the conventional ignition control apparatus.

Explanation of symbols

1: ignition control device, 2: power generation magnet, 3: control device main body, 4: pickup coil, 5: ignition coil, 6: charging coil, 7: protrusion, 8: capacitor, 9: trigger, 10: ignition signal Forming circuit, 11: misfire control circuit, 12: first resistance member, 13: transistor for misfire, 14: charging path, 15: diode, 16: power supply circuit, 17: internal power supply circuit, 18: short circuit, 19 : Misfire control circuit for external switch, 20: Switch, 21: BR terminal, 22: GW terminal, 25: Lead angle signal forming circuit, 26: Thyristor, 27: Zener diode, 28: Second resistance member, 51: Ignition control Device, 52: Magnet for power generation, 53: Control device body, 54: Pickup coil, 55: Ignition coil, 56: Coil for charging, 57: Projection 58: capacitor, 59: trigger, 60: ignition signal forming circuit, 61: misfire control circuit, 62: first resistance member, 63: transistor for misfire, 64: charging path, 65: diode, 66: power supply circuit, 67: Internal power supply circuit, 68: Short circuit, 69: External switch misfire control circuit, 70: Switch, 71: BR terminal, 72: GW terminal, 75: Lead angle signal forming circuit, 76: Thyristor, 77: Zener diode

Claims (2)

It consists of a magnet generator, a control device body, a pickup coil, and an ignition coil.
The magnet generator has a charging coil,
The outer periphery of the rotor of the magnet generator is provided with a protrusion for detecting an ignition timing signal with the pickup coil,
In the control device main body, a capacitor charged with electric power supplied from the charging coil, a trigger for discharging the ignition coil from the capacitor, and an ignition timing signal from the pickup coil An ignition signal forming circuit for turning on the trigger, and a misfire control circuit connected between the ignition signal forming circuit and the trigger,
The misfire control circuit includes a first resistance member and a misfire transistor,
One end of the first resistance member is connected to the front side of the diode provided on the front side of the capacitor in the charging path from the magnet generator to the capacitor,
Both ends of the charging coil are connected to the control device main body, one end leads to the charging path, and the other end leads to a power supply circuit for supplying power to each circuit in the control device main body. Connected to the internal power supply path,
The charging path and the internal power supply path are respectively connected to both ends of a short circuit provided in the control device body,
A second resistance member having one end grounded is connected to the internal power supply path,
The ignition control device characterized in that a resistance value of the second resistance member is lower than a resistance value of the first resistance member.   2. The ignition control device according to claim 1, wherein a resistance value of the second resistance member is 1 to 9 kΩ, and a resistance value of the first resistance member is 100 to 900 kΩ.

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