JPS635163A - Ignition device for internal combustion engine - Google Patents

Abstract

PURPOSE:To effectively prevent smoke, by constituting primary and secondary sides of an ignition coil device respectively of two parts and applying an ignition pulse to both the two parts of the primary side in the cold time. CONSTITUTION:A water temperature signal generating circuit 22 generates a signal of 1 in the cold time, and the fourth AND circuit 28 is synchronously driven with an ignition signal. Consequently, also OR circuits 30, 32 are driven synchronously with the ignition signal, and transistors 9a, 9b are simultaneously driven. As the result, both winding parts 3a, 3b are simultaneously driven, and the density of magnetic flux is doubled. Accordingly, double the current is generated in a secondary side coil 5, and the internal impedance is halved. Consequently, smoke can be effectively prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to an ignition device in a spark-ignition internal combustion engine.

[Conventional technology]

In a spark-ignition internal combustion engine, when the engine is cold, the spark plug electrode tends to smolder and insulation resistance decreases. In this case, the leakage current is large (as a result, the generated voltage decreases, and the discharge energy becomes small. In order to ensure steady ignition even in this state, it is necessary to use a power source that generates a large amount of energy. For example, Japanese Patent Laid-Open No. 55-7921 proposes that the magnitude of the primary current be made variable depending on the engine operating condition.

(Problems to be solved by the invention) - Increasing the primary current is not desirable from the power source's perspective. - As a means of increasing the ignition energy without increasing the secondary current, increase the number of turns in the coil. (In this case, the problem is that the internal impedance of the ignition coil increases.) If the internal impedance increases, even a slight smoldering of the spark plug electrode will cause a large voltage drop. death,
It will cause a misfire.

An object of the present invention is to provide a configuration of an ignition coil device that can reduce the internal impedance seen from the ignition plug side without increasing the primary current.

[Means for solving problems]

According to this invention, the primary side is comprised of a primary side that receives an ignition signal and a secondary side that is connected to an ignition plug electrode, and the primary side has a first winding portion and a second winding portion that are independently driven. On the other hand, the secondary side has a third winding part and a fourth winding part which are independently driven by the first winding part and the second winding part, respectively, and the third winding part The winding part and the fourth winding part are connected in parallel so that current flows in the same direction, and under normal conditions, an ignition signal is supplied to one of the first winding part and the second winding part. An ignition coil device for an internal combustion engine is provided, characterized in that an ignition signal is supplied to both of the ignition coil devices and the ignition coil device when necessary.

〔Example〕

FIG. 1 shows the overall configuration of the first embodiment. Reference numeral 1 indicates an ignition coil unit, which includes an iron core 2.

The primary winding 3 has a first part 3a and a second part 3b with opposite winding directions, while the secondary winding 5 has a first part 5a and a second part 3b with opposite winding directions. 5b.

In the primary winding, one ends of the first portions 3a, 3b are connected to the buffer 7.

The first winding portion 5a and the second winding portion 5b are connected to collector emitter circuits of drive transistors 9a and 9b, respectively. - side, in the secondary winding 'first winding portion 5a
, 5b are connected in parallel, the - end is grounded, and the other end is connected to the on-disk resistor 12 via the high tension cord 10.
is connected to the center electrode 12-1. The distribution electrode 12-2 is connected to the spark plug electrode 14 of each cylinder.

Normally, as will be described later, the ignition signal is supplied only to the transistor 9a. Therefore, when the transistor 9a is switched from ON to OFF, a magnetic flux density corresponding to the S number of the first winding portion 3a is generated due to the back electromotive force,
A voltage corresponding to this magnetic flux density is generated in the secondary winding 5. - On the other hand, when the engine is cold, the ignition signal is supplied to both transistors 9a and 9b. Therefore, transistor 9a
.

The magnetic flux generated by the back electromotive force when 9b switches from ON to OFF is the sum of the magnetic flux due to the first winding portion 3a and the magnetic flux due to the second winding portion 3a. That is, the magnetic flux density is twice that in the first case.

Incidentally, since the winding parts 3a and 3b or 5a and 5b are arranged in series and have a common center tap, the directions of the windings are opposite in order to generate magnetic flux in the same direction in each part. However, in the case of double winding, the winding direction can be the same direction.

16 shows an example of the configuration of an ignition control circuit. Ignition control circuit 1
6 is an ignition signal generation circuit 18 and a rotation speed signal generation circuit 2
0, water temperature signal generation circuit 22, AND circuits 24, 26
．． 27.28.29, OR circuit 30, 32.33,
It is composed of bistable circuits 34 and 36.

The ignition signal generation circuit 18 is configured to generate an ignition signal at a predetermined crank angle of the engine, and is well known in itself, so a detailed explanation will be omitted, but one employing a Lycrocomputer system is well known. ing.

The rotational speed signal generating circuit 20 generates a signal of "1" when the engine rotational speed NE is larger than a predetermined value N E o, and generates a signal of "O" when it is smaller.

The water temperature signal generation circuit 22 is configured to detect the water temperature of the engine and generate a signal of "1" when the water temperature TH- is below a predetermined value T11-0, and a signal of "0" when the water temperature TH- is above a predetermined value. Ru.

The ignition signal generation circuit 18 includes a first AND circuit 24, a second AND circuit 26, a third AND circuit 27, and a fourth AND circuit.
Connected to D circuit 28. The engine rotational speed signal generation circuit 20 is connected to the inverting input of the third AND circuit 2-7 and also to the third OR circuit 33. The water temperature signal generation circuit 22 is connected to a fourth AND circuit 28, and
It is connected to the third OR circuit 33. First AND circuit 2
The output of 4 is connected to the first OR circuit 30, as well as to the reset terminal of the first bistable circuit 34 and the set terminal of the second bistable circuit. Second AND circuit 2
The output of 6 is connected to the first bistable circuit 340 set terminal and the second
The reset terminal of the bistable circuit 36 and the second OR circuit 3
Connected to 2. The output of the third AND circuit 27 is connected to the first OR circuit 30.

The output of the fourth AND circuit 27 is connected to the first OR circuit 30 and the second OR circuit 32, and the output of the first OR circuit 30 is connected to the transistor 9a.

The output of the second OR circuit 32 is connected to the fifth AND circuit 29. Further, the output of the third OR circuit 33 is AND
The output of the fifth AND circuit 29 is connected to the transistor 9b.

To explain the operation of the embodiment shown in FIG. 1 described above, the ignition signal generation circuit 18 generates an ignition pulse signal that rises for a predetermined period every predetermined timing before the compression top dead center at which ignition is to be performed (see FIG. (c)).

After the engine warms up, the water temperature signal generation circuit 22 generates a signal of 0'' (Fig. 2 (b)). Therefore, the fourth AND
The circuit 28 outputs an "O" signal (G). If the engine speed is high (Fig. 2-B), the engine speed signal generation circuit 20 generates a signal of "1" (second
Figure) (a)).

Therefore, the third AND circuit 27 generates a signal of "01," and the third OR circuit 33 turns on.
A "1" signal is input to one input of the AND circuit 29.

The first and second AND circuits 24 and 26 alternately
It becomes N. That is, when the first AND circuit 24 is turned ON by the arrival of the ignition pulse signal, the first bistable circuit 34 is reset, and the second bistable circuit 36 is reset, so that the first AND circuit 24 is turned ON. O at next ignition pulse
No, the second AND circuit 26 is turned on.

At the time of the next ignition pulse, the first AND circuit 24 is ON.
Therefore, the second AND circuit 26 is turned off.

See (nu) and (ru) in Figure 2. Since the OR circuits 30 and 32 are alternately set to 11, the transistors 9a and 9b are alternately turned on (Fig. 2 (force) and (y)), and the winding portions 3a and 3b of the ignition coil are alternately excited. , the magnetic flux density becomes a normal value. By performing alternate driving during high rotation, sufficient charging time for the primary coil can be obtained, and sufficient energy can be generated.

On the other hand, when the engine speed is low (Figure 2-○), the third OR circuit 33 outputs a "0" signal, so the fifth AND
The circuit 29 is always turned off and the transistor 9b is not driven (Y). - On the other hand, since a signal synchronized with the ignition pulse is output from the third AND circuit 27 (vi), the OR circuit 30 is turned on in synchronization with the ignition signal (v), and the transistor 9a is driven. That is, during low rotation after warming up, only one transistor 9a is driven in synchronization with the ignition signal.゛During the cold period (Fig. 2-A), the water temperature signal generation circuit 20 is
", and the fourth AND circuit 28 is driven in accordance with the ignition signal (G). Therefore, the OR circuit 30.
32 is also driven in synchronization with the ignition signal, and the transistor 9a
, 9b are simultaneously driven (force), (yo). Therefore,
Both winding portions 3a, 3b are driven simultaneously, and the magnetic flux density is doubled.

In the second embodiment shown in FIG. 3, the ignition coils are set to 1-1 in a 6-cylinder internal combustion engine. l-2,1-3゜1-4.1-5
．． 1-6 is installed for each cylinder. Transistor 9-1.9 on the primary side of the ignition coil
-2.9-3.9-4.9-5.9-6 are connected, and the ignition pulse signal of that cylinder is supplied to the base. The secondary side is the spark plug electrode 14-1.14-2.14-3 of that cylinder.
Connected to ゜14-4.14-5.14-6. The secondary side of the ignition coil is a combination of cylinders with a 360° phase difference (
Set the firing order to #1. #5. #3. #6゜#2. #4, #l and #6. High tension code 20 for each #5 and #2゜#3 and #4).

Diodes 22-1.2 are connected in parallel with each other by 202-, , 2k, and cause the current direction to be reversed.
2-2.22-3.22-4.22-5°22-6 will be installed.

During warm-up, only the transistor of that cylinder (for example, transistor 9-1 if the cylinder to be ignited is #1) is driven.
Normal ignition current occurs.

When cold, not only the transistor of that cylinder but also the 360
The transistors of the cylinders having different a phases (for example, if the cylinder to be ignited is #l, the transistor 9-6 of #6) is driven. Therefore, since the secondary coils are connected in parallel, the current is doubled and the internal impedance is halved.

This invention can also be applied to an ignition system in which one ignition coil is installed for each of two cylinders with a 360-phase difference, by an arrangement similar to that shown in FIG. 3.

〔effect〕

According to this invention, the primary side and the secondary side of the ignition coil device each consist of two parts, and by applying an ignition pulse to both the primary sides when cold, the current is doubled on the secondary side. occurs and the internal impedance is halved,
Smoldering can be effectively prevented.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of the first embodiment. FIG. 2 is a timing diagram illustrating the operation of the second embodiment. FIG. 3 is a configuration diagram of the second embodiment. 1...Ignition coil 2...Iron core 3...-Secondary coil 5...Secondary coil 9a, 9b...Transistor 12...Distributor '14...
Spark plug electrode 16...ignition control circuit

Claims (1)

[Claims] It consists of a primary side that receives the ignition signal and a secondary side that is connected to the spark plug electrode, the primary side having a first winding part and a second winding part that are independently driven, while the secondary side is the first
The third winding part and the fourth winding part are independently driven by the winding part and the second winding part, respectively, the third winding part and the fourth winding part are connected in parallel so that current flows in the same direction, and normally the first winding part and the second winding part are connected in parallel so that current flows in the same direction.
An ignition device for an internal combustion engine, characterized in that an ignition signal is supplied to one side of the winding portion of the engine, and an ignition signal is supplied to both sides when necessary.