JP2001355553A - Igniter for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an igniter securing the high ignition energy to an engine requiring high ignition energy such as an environmentally friendly engine with an ignition coil and a less power transmission heating and preventing the igniter whole body from being complicated. SOLUTION: This igniter for the internal combustion engine is provided with a boosting means boosting a power voltage fed to a primary coil of the ignition coil to a voltage exceeding 14 V and the voltage boosted to exceeding 14 V is fed to the primary coil of the igniter so that this igniter can secure the high ignition energy with the ignition coil and the less power transmission heating.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ignition device for an internal combustion engine for supplying a high voltage to an ignition coil.

[0002]

2. Description of the Related Art FIG. 3 shows a conventional ignition device for an internal combustion engine. FIG. 4 is a time series diagram showing the relationship between primary coil current waveforms of an ignition coil in an ignition device for an internal combustion engine to which the conventional technology is applied, and FIG. FIG. 3 is a time series diagram showing a relationship between an ignition device for an internal combustion engine corresponding to an environmental engine requiring energy and a primary coil current waveform of an ignition coil.

The conventional ignition device for an internal combustion engine controls the ignition of multiple cylinders with one ignition signal control circuit.
An ignition device for an internal combustion engine mounted on a cylinder engine, wherein the ignition signal control circuit controls switching elements of a plurality of ignition coils. The ignition coil is an independent ignition coil that supplies a high voltage generated in one ignition coil to one ignition plug. Further, cylinder numbers exist in a normal order from a certain position of the timing belt of the engine, and the ignition coil of the ignition device for the internal combustion engine has:
One engine is mounted on each cylinder, such as one engine for the first cylinder (hereinafter referred to as “# 1”) and one engine for the second cylinder (hereinafter expressed as “# 2”).

In FIG. 3, reference numeral 71 denotes a power supply, and its voltage is 14 V in the conventional technique. 11 is a primary coil, 21 is a secondary coil, 41 is a switching element, 51
Denotes an ignition signal control circuit, and 61, 62, 63 and 64 denote ignition plugs. One end of the primary coil 11 is connected to the positive electrode of the power supply 71, the other end is connected to the collector of the switching element 41, and the high voltage side end of the secondary coil 21 is a spark plug 61, 62, 63. , 64 at one end. Further, the ignition signal control circuit 51 generates one continuous pulse wave at the timing of controlling the switching element 41, and the pulse wave is input to the base terminal of the switching element 41.

Here, when the switching element 41 is turned on at the rising timing of a certain pulse of one continuous pulse wave generated by the ignition signal control circuit 51, as shown in FIG. The primary coil 11 of the connected ignition coil is energized, and a magnetic field is generated in the primary coil 11. The generated magnetic field is held by the iron core. While a certain pulse of the pulse wave is rising, the primary coil 11 of the ignition coil is kept energized, and the switching element 41 is turned off at the falling timing of the pulse.
When F is reached, the current flowing through the primary coil 11 of the ignition coil connected to the # 1 cylinder is cut off. At the time of interruption, the energy of the magnetic field of the iron core held is generated as a high voltage at the end of the secondary coil 21.

The next pulse generated by the ignition signal control circuit 51 turns on the switching element 41 at the rising timing of the pulse, thereby turning on the switching element 41 of the ignition coil connected to the # 3 cylinder.
From this, the primary coil 11 of the ignition coil connected to the # 3 cylinder is energized, and while the another pulse is rising, the primary coil 11 of the ignition coil of the # 3 cylinder is energized. When the switching element 41 is turned off at the falling timing of another pulse, the current flowing through the primary coil 11 of the ignition coil connected to the # 3 cylinder is cut off. Thus, a high voltage is generated in the secondary coil 21 of the # 3 cylinder ignition coil.

As described above, the conventional ignition device for an internal combustion engine controls the ignition of multiple cylinders with one ignition signal control circuit. Had surplus.

[0008]

With the recent improvement in fuel efficiency and emission regulations, the demand for environmental engines such as lean burn engines and gasoline direct injection engines is increasing year by year.
These environmental engines burn lean fuel in the cylinders to ensure stable combustion, and are therefore 2 times less than conventional general engines.
Up to three times the ignition energy is required.

The ignition energy generated in the secondary coil of the ignition coil is represented by E1 [J], the electromagnetic energy stored in the primary coil of the ignition coil, L [H], and the inductance of the primary coil. When represented by a breaking current value I [A], it is generally represented by the following equation.

(Equation 1) The above equation (1) indicates that the value of 1
From the above equation, the energy stored in the primary coil, which is the electromagnetic energy stored in the secondary coil, is proportional to the inductance L of the primary coil and the cutoff current value I of the primary coil. In order to increase the ignition energy, it is necessary to either increase the breaking current value of the primary coil or increase the inductance of the primary coil. However, in order to increase the cut-off current value of the primary coil, the charging time, which is the time for energizing the primary coil, must be increased. If the inductance of the primary coil is further increased, the rise of the primary current is delayed, and it takes time to reach a predetermined current. Therefore, in any case, in order to secure ignition energy two to three times as compared with a conventional general engine, the energization time to the primary coil becomes longer.

Further, since the prior art is an ignition device for an internal combustion engine in which a plurality of ignition coils are controlled by one ignition signal control circuit, a certain pulse is used in a certain ignition and a certain pulse is used in a certain ignition. Since one ignition is controlled by one pulse as in use, when the ignition coil is controlled over a long energizing time as described above, the time between pulses is controlled as shown in FIG. Have no margin and overlap and cannot be controlled. Therefore, the primary coil charging time could not be sufficiently extended, and sufficient ignition energy from the secondary coil could not be secured.

Also, the ignition signal control circuit of the ignition coil is assigned to each ignition coil so that the primary coil charging time in each ignition cycle may overlap, and high energy such as an environmental engine is required. Means for securing the necessary ignition energy even in the ignition coil for the internal combustion engine may be considered.

However, by individually allocating the ignition signal control circuits of the ignition device, the space for installing the ignition signal control circuit is increased, the wiring length is increased, and power is allocated to the ignition signal control circuit. This complicates the entire ignition device.

In view of the above, the present invention provides an ignition device for an internal combustion engine which requires a high energy and is used for an environmental engine such as a lean burn engine and a gasoline direct injection engine. With the goal.

[0014]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, an ignition device for an internal combustion engine according to the present invention boosts a power supply voltage supplied to a primary coil of an ignition coil to a voltage exceeding 14V, preferably 42V. A boost driver as boost means is provided to supply a voltage exceeding 14 V, preferably a voltage boosted to 42 V, to the primary coil of the ignition coil.

[0015]

According to the present invention, by increasing the power supply voltage supplied to the primary coil of the ignition coil to a voltage exceeding 14 V, preferably 42 V, the rise time of the primary current waveform is shortened, and the conventional power supply voltage of 14 V is used. As compared with the case where the ignition coil is driven, the charging of the primary coil can be performed in a shorter time to secure the ignition energy generated in the same secondary coil. Therefore, when used in an ignition coil device corresponding to an environmental engine requiring high energy, even if the pulse interval is short, a sufficient primary coil can be charged and an ignition spark having sufficient ignition energy can be obtained. The conventional problem can be solved.

Since the charging time of the primary coil, which is the time for energizing the primary coil 11, is short, the switching element 4
1 is short, so that the switching element 4
1 generates less heat.

[0017]

1 is a drawing of an ignition device for an internal combustion engine to which the technology of the present invention is applied. FIG. 2 is a drawing of a primary coil current waveform of an ignition coil connected to # 1 cylinder and # 3 cylinder of the embodiment to which the technology of the present invention is applied.

FIG. 1 shows an embodiment. In the ignition coil of the present invention, in FIG.
The voltage exceeds 4V. The primary coil 11 and the secondary coil 21 are arranged coaxially with the iron core. One end of the primary coil 11 is connected to the positive electrode of the power supply 71, the other end is connected to the collector of the switching element 41, and the high-voltage side end of the secondary coil 21 is a spark plug 61, 62, 63. , 64 at one end.

The ignition signal control circuit 51 generates one continuous pulse wave at a timing for controlling the switching element 41 and inputs the pulse wave to the base terminal of the switching element 41. Further, the power supply 71 and the primary coil 11
Between them, a boost driver 31 is provided, and a voltage boosted to a voltage exceeding 14 V is supplied to the primary coil 11. The step-up driver 31 is a step-up (Boost) DC-DC converter, which stores electromagnetic energy in the inductance Lb81 when the switching transistor 85 is ON, and
A circuit that superimposes electromagnetic energy on an input power supply at the time of F and extracts the output to an output, and can extract an output voltage higher than an input voltage. It goes without saying that the components of the ignition coil to which the technique of the present invention is applied are designed to withstand a voltage exceeding 14V.

Thus, by applying the technique of the present invention as in the embodiment, the problem can be easily solved with a simple configuration as compared with the conventional ignition device.

[0021]

By applying the technology of the present invention to an ignition device, a necessary high ignition energy can be secured even for an engine requiring a high ignition energy such as an environmental engine. In addition, since the heat generated by the ignition coil and the power truss can be reduced, the ignition device can be provided in which the entire ignition device is not complicated by a simple method of simply providing the booster driver.

[Brief description of the drawings]

FIG. 1 is a drawing of an ignition device for an internal combustion engine to which the technology of the present invention is applied.

FIG. 2 is a drawing of a primary coil current waveform of an ignition coil connected to # 1 cylinder and # 3 cylinder of an embodiment to which the technology of the present invention is applied.

FIG. 3 is a diagram of an ignition device for an internal combustion engine showing a conventional technique.

FIG. 4 shows an ignition device for an internal combustion engine to which the prior art is applied, which is one of ignition coils connected to cylinders # 1 and # 3.
It is a time series diagram of the relationship of a next coil current waveform.

FIG. 5 is an ignition device to which the prior art is applied, which is an ignition device for an internal combustion engine corresponding to an environmental engine requiring high energy, and a primary coil current of an ignition coil connected to cylinders # 1 and # 3. It is a time series diagram of the relationship of a waveform.

[Explanation of symbols]

 In the drawings, the same reference numerals indicate the same or corresponding parts. DESCRIPTION OF SYMBOLS 11 Primary coil 21 Secondary coil 31 Step-up driver 41 Switching element 51 Ignition signal control circuit 61, 62, 63, 64 Ignition plug 71 Power supply 81 Inductance Lb 82 Diode 83 Capacitor 84 Transmission circuit 85 Switching transistor

Claims (2)

[Claims] An ignition coil including a primary coil coaxially arranged with an iron core, a secondary coil coaxially arranged with respect to a magnetic path of the iron core, and an ignition for controlling energization of the primary coil. An ignition device for an internal combustion engine having a signal control circuit, wherein the ignition signal control circuit controls a plurality of ignition coils with one ignition signal control circuit in particular. An ignition device for an internal combustion engine, comprising: 2. The power supply voltage used for the ignition coil is 1
An ignition method characterized in that the voltage is raised to a voltage exceeding 4 V and a primary coil charging time, which is a time for energizing the primary coil of the ignition coil, is advanced.