JP2009068443A - Ignition coil for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ignition coil for an internal combustion engine capable of maintaining high output performance from a low speed zone to a high speed zone of the internal combustion engine. <P>SOLUTION: A primary coil 1 is divided to a first divided primary coil 11 of which primary resistance is 0.3 Ω and of which the number of primary windings is 60, and a second divided primary coil 12 of which primary resistance is 0.5 Ω and of which the number of primary windings is 100. Primary current is carried to only the first divided primary coil 11 when electricity carry time to the primary coil 1 is less than 2 ms, and to both of the first divided primary coil 11 and a second divided primary coil 12 when electricity carry time to the primary coil 1 is 2 ms or longer to change primary resistance and the number of primary windings of the primary coil 1 to which electricity is carried. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an ignition coil for an internal combustion engine for supplying a high voltage to an ignition plug of an internal combustion engine such as an automobile to generate a spark discharge, and more particularly, to change a rise time of a primary current, The present invention relates to an ignition coil for an internal combustion engine that can maintain high output performance from a high rotation range to a high rotation range.

  In general, an ignition coil for an internal combustion engine forms an electromagnetic circuit with a primary coil, a secondary coil, and an iron core, and controls energization / cutoff of the primary coil to greatly change the excitation direction of magnetic flux generated in the electromagnetic circuit. Cause electromagnetic induction. Then, the counter electromotive force generated by the electromagnetic induction is boosted by the turn ratio of the primary coil and the secondary coil, a high voltage is generated in the secondary coil, and supplied to the ignition plug of the internal combustion engine.

Therefore, a conventional ignition coil for an internal combustion engine includes a primary coil for forming an electromagnetic circuit in an insulating case, a secondary coil disposed outside the primary coil, the secondary coil and the primary coil. A power switch that is arranged inside the coils and controls the energization and shut-off of the primary coil and magnetically coupling these coils, and one of the three terminals is connected to one end of the primary coil And at least are housed. A permanent magnet magnetized in the direction opposite to the direction of excitation of magnetic flux generated in the electromagnetic circuit by energization of the primary coil is disposed in the iron core. Then, the insulating resin is injected into the insulating case and cured, and necessary insulation in the insulating case is maintained.
The three terminals of the power switch are a collector terminal, a signal terminal (base terminal), and a ground terminal (emitter terminal), and the collector terminal of these is connected to one end of the primary coil. Further, one end of the secondary coil is connected to the spark plug in order to supply the generated high voltage.

  An electromagnetic circuit in a conventional ignition coil for an internal combustion engine is, for example, as shown in FIG. That is, the electromagnetic circuit 10 includes a primary coil 1, a secondary coil 2, an iron core 3 that magnetically couples the secondary coil 2 and the primary coil 1, and a power switch 4 connected to one end of the primary coil 1. It consists of Specifically, the collector terminal 4 a of the power switch 4 is connected to one end of the primary coil 1 and is connected to the output side 51 of the battery 5 as an external power source via the primary coil 1. Further, the signal terminal 4 b of the power switch 4 is connected to an external signal generator 6 that controls energization and interruption of the primary coil 1, and the ground terminal 4 c of the power switch 4 is connected to the input side 52 of the battery 5. . The secondary coil 2 has one end connected to the spark plug 7 and the other end connected to the output side 51 of the battery 5 via the diode 8.

Next, the operation of the electromagnetic circuit 10 when the ignition coil for the internal combustion engine is operated will be described.
First, a control signal generated by the external signal generator 6 is transmitted to the signal terminal 4b. Subsequently, the power switch 4 performs an on / off operation in response to the control signal, and controls energization and interruption of the primary coil 1. Then, in the electromagnetic circuit 10, the excitation direction of the magnetic flux changes abruptly to cause electromagnetic induction. Due to this electromagnetic induction, a high voltage is generated in the secondary coil 2 and a high voltage is supplied from the secondary coil 2 to the ignition plug 7 of the internal combustion engine.

Patent Document 1 below proposes an internal combustion engine ignition coil that applies an electromagnetic circuit in a conventional internal combustion engine ignition coil and can supply a high voltage to two ignition plugs with a single electromagnetic circuit. .
JP 2006-283568 A

  However, the conventional electromagnetic circuit 10 in the internal combustion engine ignition coil has a problem in that high output performance cannot be maintained from a low rotation range to a high rotation range of the internal combustion engine. That is, when the internal combustion engine reaches the high rotation range, the number of ignitions increases, and the amount of heat generated by the primary coil 1 increases. Therefore, it is necessary to shorten the energization time of the primary coil 1 by limiting the heat resistance temperature of the primary coil 1. In order to obtain high output in a short energization time, a large electric wire is used for the primary coil 1, the primary resistance value is reduced, and the primary current rise time is increased to ensure high output performance up to the high rotation range of the internal combustion engine. Yes, but this resulted in another problem that could not be addressed without increasing the size of the internal combustion engine ignition coil.

  Therefore, the present invention has been proposed in view of the above circumstances, and it is possible to cope with an increase in the number of ignitions in a high rotation range of an internal combustion engine by changing the rise time of the primary current, and in particular shortening the rise time of the primary current. An object of the present invention is to provide an ignition coil for an internal combustion engine that can maintain high output performance even in a high rotation range of the internal combustion engine.

  In order to achieve the above object, an ignition coil for an internal combustion engine according to the present invention has a primary coil and a secondary coil fitted on the outside of an iron core, and has an opposite direction to the excitation direction by energization of the primary coil in the iron core. In an internal combustion engine ignition coil in which a permanent magnet magnetized in a direction is arranged, the primary coil is divided into a plurality of parts, and the primary coil is switched in a plurality of ways according to the length of energization time to the primary coil. By changing the primary resistance value and the number of primary turns of the primary coil to be energized, the shorter the energization time to the primary coil, the faster the rise time of the primary current, and the energization time to the primary coil The longer it is, the longer the rise time of the primary current is.

  Further, in the ignition coil for an internal combustion engine, when the energization time is less than the switching energization setting time, the primary resistance value of the primary coil to be energized is set to 0.2 to 0.6Ω and the primary winding When the energization time is equal to or longer than the switching energization set time, the primary resistance value of the energized primary coil is set to 0.4 to 1.0Ω and the number of primary turns Is preferably 80 to 200 times.

  In the present invention, the primary coil is divided into a plurality of parts, and the primary coil is switched in a plurality of ways according to the energization time of the primary coil, thereby changing the primary resistance value and the number of primary turns of the energized primary coil. The shorter the energization time to the primary coil, the faster the rise time of the primary current, and the longer the energization time to the primary coil, the slower the rise time of the primary current. It is possible to cope with an increase in the number of ignitions in the high speed region of the internal combustion engine. In addition, the primary coil's number of primary turns is reduced and the rise time of the primary current is shortened, so the turn ratio of the primary coil and secondary coil is relatively increased, and a high voltage is generated in the secondary coil. And high output performance can be maintained. On the other hand, since the rise time of the primary current is delayed by increasing the primary resistance value and the number of primary turns of the primary coil, high energy can be generated in the secondary coil. In the rotation region, the high energy can be supplied to the spark plug to improve the combustion stability.

  Furthermore, when the energization time is less than the switching energization setting time, the primary resistance value of the primary coil to be energized is set to 0.2 to 0.6Ω and the number of primary turns is set to 60 to 140 times. Since the primary resistance value and the number of primary turns are reduced and the rise time of the primary current is increased, it is possible to cope with an increase in the number of ignitions in the high speed region of the internal combustion engine. Furthermore, since the number of primary turns of the primary coil has decreased, the turn ratio of the primary coil and the secondary coil can be relatively increased, and a high voltage can be generated in the secondary coil, maintaining high output performance. can do. When the energization time is longer than the switching energization setting time, the primary resistance value of the primary coil to be energized is set to 0.4 to 1.0Ω, and the primary winding number is set to 80 to 200 times. Since the rise time of the primary current is delayed by increasing the primary resistance value and the number of primary turns, high energy can be generated in the secondary coil. It is possible to increase the combustion stability by supplying energy to the spark plug.

  That is, the present invention divides the primary coil into a plurality of parts, and switches the primary coil in a plurality of ways according to the length of the energization time to the primary coil, thereby reducing the primary resistance value and the number of primary turns of the primary coil to be energized. The primary current rise time is shortened as the energization time to the primary coil is shortened, and the rise time of the primary current is delayed as the energization time to the primary coil is increased, so a high voltage is generated in the secondary coil. It is possible to cope with an increase in the number of ignitions in the high rotation range of the internal combustion engine, to prevent misfire of the ignition plug in the high rotation range of the internal combustion engine, and to maintain high output performance, and to achieve the primary coil The primary resistance value and the number of primary turns can also be increased.For example, high energy is generated in the secondary coil even in the low rotation range of the internal combustion engine, and this is used as a spark plug. It is possible to provide a supply to an ignition coil for an internal combustion engine which can enhance the combustion stability.

Hereinafter, the present invention will be described in detail with reference to the drawings illustrating an embodiment.
FIG. 1 is a schematic diagram of an electromagnetic circuit in an ignition coil for an internal combustion engine according to an embodiment of the present invention. 2 that are the same as or equivalent to those shown as the conventional example in FIG.

  As shown in FIG. 1, the ignition coil for an internal combustion engine according to the present invention is obtained by dividing the primary coil 1 into, for example, a first divided primary coil 11 and a second divided primary coil 12 in an electromagnetic circuit 10. Depending on the energization time to the primary coil 1, the primary coil 1 can be changed into, for example, only the first divided primary coil 11 or both the first divided primary coil 11 and the second divided primary coil 12. By switching to, the primary resistance value and the number of primary turns of the primary coil 1 to be energized are changed. A first power switch 41 is connected to one end of the first split primary coil 11, and a second power switch 42 is connected to one end of the second split primary coil 12.

Specifically, one end of the first divided primary coil 11 is connected to the other end of the second divided primary coil 12, and is connected to the collector terminal 41a of the first power switch 41. The power switch 41 is connected to the input side 52 of the battery 5 through a ground terminal (emitter terminal) 41 c. One end of the second divided primary coil 12 is connected to the collector terminal 42a of the second power switch 42, and the input side of the battery 5 through the ground terminal 42c (emitter terminal) of the second power switch 42. 52.
The signal terminal 41 b (base terminal) of the first power switch 41 and the signal terminal 42 b (base terminal) of the second power switch 42 are switched energization time of the control signal supplied from the external signal generator 6. If the power is less than the first power switch 41, an ON signal is supplied to the signal terminal 41b. When the energization time of the control signal supplied from the external signal generator 6 is longer than the switching energization setting time, the first power The switch 41 is connected to an electronic circuit 43 that supplies an ON signal to the signal terminal 41 b of the switch 41 and the signal terminal 42 b of the second power switch 42.

  The first split primary coil 11 is, for example, one having a primary resistance value of 0.3Ω and a primary winding number of 60. As the second divided primary coil 12, for example, a primary resistance value of 0.5Ω and a primary winding number of 100 are adopted. On the other hand, for the secondary coil 2, for example, a secondary resistance value of 20 kΩ and a secondary winding number of 8000 is adopted.

  Hereinafter, the operation of the electromagnetic circuit 10 when the ignition coil for the internal combustion engine according to the present invention is operated will be described in the case where the switching energization setting time of the electronic circuit 43 is set to 2 milliseconds, for example. The energization time for the primary coil 1 is controlled by the signal generator 6.

  First, a control signal is supplied from the signal generator 6 to the electronic circuit 43. When the energization time in this control signal is less than 2 milliseconds, the electronic circuit 43 is turned on / off to the signal terminal 41b of the first power switch 41. Since the signal is output and the OFF signal is output to the signal terminal 42b of the second power switch 42, only the first power switch 41 performs the ON / OFF operation so that the primary current is the first divided primary coil. Only 11 is energized and cut off. Then, since the primary resistance value of the first divided primary coil 11 is 0.3Ω and the number of primary turns is 60, the rise time of the primary current in the electromagnetic circuit 10 is accelerated. Moreover, since the secondary resistance value of the secondary coil 2 is 20 kilo ohms and the secondary winding number is 8000 times, the winding ratio with the primary coil 1 (first divided primary coil 11) is relatively increased, A large high voltage is generated in the secondary coil 2. Therefore, the ignition coil for an internal combustion engine according to the present invention accurately responds to the increase in the number of ignitions of the spark plug 7 in the high rotation range of the internal combustion engine and supplies a large high voltage to the spark plug 7 to Maintains high output performance even at high rotational speeds.

  In addition, when a control signal is supplied from the signal generator 6 to the electronic circuit 43 and the energization time in this control signal is 2 milliseconds or more, the electronic circuit 43 is first switched until the energization time becomes 2 milliseconds. An ON signal is output to the signal terminal 41 b of the power switch 41 and an OFF signal is output to the signal terminal 42 b of the second power switch 42. Further, when the energization time exceeds 2 milliseconds, the electronic circuit 43 outputs an off signal to the signal terminal 41 b of the first power switch 41 and outputs an on signal to the signal terminal 42 b of the second power switch 42. After a predetermined energization time, the electronic circuit 43 outputs an off signal to the signal terminal 42b of the second power switch 42. That is, when both the first power switch 41 and the second power switch 42 are turned on and off, the primary current is supplied to both the first divided primary coil 11 and the second divided primary coil 12. Energized and shut off. Then, since the sum of the primary resistance values of the first split primary coil 11 and the second split primary coil 12 is 0.8Ω and the total number of primary turns is 160 times, a large number of primary turns and a large primary resistance value are obtained. Thus, the primary current is passed through the primary coil 1 and is cut off, and high energy is generated in the secondary coil 2. Therefore, the ignition coil for an internal combustion engine according to the present invention supplies the high energy to the spark plug 7 and enhances the combustion stability, for example, in the low rotation range of the internal combustion engine.

  Therefore, the ignition coil for an internal combustion engine according to the present invention divides the primary coil 1 into two parts, the first divided primary coil 11 and the second divided primary coil 12, and according to the energization time to the primary coil 1, By switching the primary coil 1 to be energized to only the first divided primary coil 11 or to both the first divided primary coil 11 and the second divided primary coil 12, the energized primary coil 1 Since the primary resistance value and the number of times of primary winding are changed, when the energization time to the primary coil 1 is less than the switching energization setting time, the primary current is energized and cut off only to the first divided primary coil 11. The primary resistance value and the number of primary turns are reduced by this, and the rise time of the primary current is increased. Therefore, it is possible to cope with the increase in the number of ignitions of the spark plug 7 in the high rotation range of the internal combustion engine. It is possible to prevent the misfire of the fire plug 7. Furthermore, since the turns ratio of the secondary coil 2 and the primary coil 1 (first divided primary coil 11) is relatively increased, a large high voltage is generated in the secondary coil 2 and a large high voltage is generated in the spark plug 7. A voltage can be supplied, and high output performance can be maintained even in a high rotation range of the internal combustion engine.

  Further, when the energization time to the primary coil 1 is equal to or longer than the switching energization setting time, the primary current is energized and interrupted to both the first divided primary coil 11 and the second divided primary coil 12, thereby Since the primary current can be turned on and off with a large primary winding number and a large primary resistance value by using the primary resistance value and the primary winding number, high energy is generated in the secondary coil 2 to generate the spark plug 7. For example, combustion stability can be improved in a low rotation range of the internal combustion engine.

  Here, in the above embodiment, the primary resistance value of the first divided primary coil is set to 0.3Ω, the number of primary turns is set to 60 times, and the primary resistance value of the second divided primary coil is set to 0.5Ω, Although the example which divided the primary coil into two with the primary winding number set to 100 was shown, the primary resistance value of the first divided primary coil is 0.2 to 0.6Ω, and the primary winding number is 60 to 140 times. If the total primary resistance value of the entire primary coil is in the range of 0.4Ω to 1.0Ω and the total number of primary turns is in the range of 80 to 200 times, an appropriate primary coil can be adopted. it can. Also for the secondary coil, the secondary resistance value is 20 kilo Ω and the secondary winding number is 8000 times, but the secondary resistance value is 5 to 25 kilo Ω, and the secondary winding number is 6000 to 20000 times. If it is within the range, an appropriate secondary coil can be adopted. Even in such an embodiment, it is possible to prevent the ignition plug from misfiring by shortening the rise time of the primary current to cope with the increase in the number of ignitions and maintaining a high voltage in the high rotation range of the internal combustion engine. In addition, for example, it is possible to provide an ignition coil for an internal combustion engine that can improve combustion stability by supplying high energy to the ignition plug even in a low rotation range of the internal combustion engine.

  As mentioned above, although embodiment of this invention was explained in full detail, unless this invention deviates from the matter described in the claim, various design changes are performed without being limited to the said embodiment. It is possible.

  In the above embodiment, the primary coil is divided into the first divided primary coil and the second divided primary coil, and the example in which the primary coil to which the primary current is energized and cut off is switched in two ways has been described. As long as the primary coil can be divided into a plurality of and the primary coil that is energized and cut off by the primary current can be switched in a plurality of ways, a primary coil that is divided in two or more appropriate ranges can be employed. For example, an embodiment in which the primary coil is divided into three, two switching energization setting times are set, and the primary coil that is energized and interrupted by the primary current is switched in three ways is also preferable. In such an embodiment, depending on the performance required by the internal combustion engine, etc., the primary resistance value and the primary winding number of the primary coil that is energized and interrupted by the primary current can be switched in three ways after detailed examination. Therefore, in addition to the effects of the present invention described above, it is also possible to provide an internal combustion engine ignition coil that can finely meet the demands of the internal combustion engine to be applied.

  Moreover, although the example which set the switching energization setting time of the electronic circuit to 2 milliseconds was demonstrated, this switching energization setting time should just be set between 1 millisecond-3 milliseconds. This is because the energization time of the primary coil in the high rotation range differs from 1 millisecond to 3 milliseconds depending on the vehicle type.

It is the schematic of the electromagnetic circuit in the ignition coil for internal combustion engines which concerns on one Embodiment of this invention. It is the schematic of the electromagnetic circuit in the conventional ignition coil for internal combustion engines.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Primary coil 11 1st division | segmentation primary coil 12 2nd division | segmentation primary coil 2 Secondary coil 3 Iron core 4 Power switch 4a Collector terminal 4b Signal terminal 4c Ground terminal 41 1st power switch 41a Collector terminal 41b Signal terminal 41c Ground terminal 42 Second power switch 42a Collector terminal 42b Signal terminal 42c Ground terminal 43 Electronic circuit 5 Battery 51 Battery output side 52 Battery input side 6 Signal generator 7 Spark plug 8 Diode 10 Electromagnetic circuit

Claims (2)

In an internal combustion engine ignition coil in which a primary coil and a secondary coil are fitted to the outside of an iron core, and a permanent magnet magnetized in a direction opposite to an excitation direction by energization of the primary coil is disposed in the iron core.
The primary coil is divided into a plurality of parts, and the primary coil is switched in a plurality of ways according to the duration of energization to the primary coil, thereby changing the primary resistance value and the number of primary turns of the energized primary coil. The shorter the energization time to the primary coil, the faster the rise time of the primary current, the longer the energization time to the primary coil, the slower the rise time of the primary current,
An ignition coil for an internal combustion engine. The ignition coil for an internal combustion engine according to claim 1,
When the energization time is less than the switching energization set time, the primary resistance value of the primary coil to be energized is set to 0.2 to 0.6Ω, and the primary winding number is set to 60 to 140 times.
When the energization time is equal to or longer than the switching energization set time, the primary resistance value of the primary coil to be energized is set to 0.4 to 1.0Ω, and the primary winding number is set to 80 to 200 times.
An ignition coil for an internal combustion engine.

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