JP3188627B2 - Ignition control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ignition control device, and more particularly to an ignition control device in which a power supply voltage is boosted by a DC-DC converter and supplied to the ignition device.

[0002]

2. Description of the Related Art Various types of ignition control devices for automobile engines are used. For example, in a motorcycle, a DC-DC converter boosts a power supply voltage and supplies it to a CDI type ignition device (DCCDI). There is. Further, in this DCCI type ignition device, there is an ignition device using an electronic circuit element such as a CPU or an IC for the control.

FIG. 3 schematically shows a circuit configuration of a control device of a conventional DCCI type ignition device. AC generator 1
Is connected to the battery 3 via the regulator 2 and to one end of the primary winding 16a in the transformer 16 of the DC-DC converter 5 via the overvoltage protection circuit 4. This transformer 16 has two secondary windings, a first secondary winding 16b is connected to the ignition device 8, and a second secondary winding 16b is provided.
The next winding 16c is connected to the advance angle control CPU 9.
The other end of the primary winding 16a has a switching transistor T controlled by the DC-DC converter control circuit 7.
And selectively grounded.

[0004] If both the first secondary winding 16b and the second secondary winding 16c are flybacks, the secondary windings affect each other. In particular, the first two
On the secondary winding 16b side, the voltage Vc of the CDI capacitor Cc has a sawtooth shape due to charging, and the voltage and waveform vary relatively greatly depending on the engine speed.
The voltage Vcc on the PU9 side fluctuates. When the power supply voltage Vb is low, such as when the battery 3 fails, the lead angle control C
The power is supplied to the PU 9 and there is a concern that the power supplied to the ignition device 8 decreases. Therefore, conventionally, in order to avoid this, the first secondary winding 16b and the second secondary winding 1
6c were wound in opposite directions so as not to affect each other (one forward and the other flyback).

[0005]

However, the provision of the overvoltage protection circuit 4 complicates the circuit configuration of the ignition control device, and the voltage drop caused by the thyristor of the overvoltage protection circuit 4, especially when the power supply voltage Vb decreases, is reduced. It becomes a problem. Further, in the control device of the DCCI type ignition device, the primary winding 1 is turned on / off by the switching transistor T by the DC-DC converter control circuit 7.
By controlling the current on the 6a side, the first secondary winding 16b
Side voltage Vc can be controlled, so that the overvoltage protection circuit 4 is actually provided only to protect the circuit on the side of the second secondary winding 16c. It was desired to respond by a circuit.

Here, the overvoltage protection circuit 4 is simply omitted, a diode is inserted instead, and the second secondary winding 16
It is conceivable that the c-side diode D 2 , the resistor R 2 , the capacitor C 2 and the zener diode ZD 2 correspond. In this case, the fluctuation of the voltage Vdd on the primary winding 16a directly affects the voltage VN3 on the second secondary winding 16c. For example, when the battery 3 fails, Vb is 3 V to 35 V
(At this time, Vdd is a voltage drop of a diode of 2 to 34 V). However, in order to operate the CPU 9 even at Vb = 3 V, the CPU 9 is operated at 5 V, the number of turns N1 of the primary winding 16a and the second The ratio N1: N3 to the number of turns N3 of the secondary winding 16c may be set to 1: 3 and VccＶ5V. However, when Vdd = 34V, VN3 = 102V, so that the influence on Vcc is avoided. Because of the resistance R 1
And circuit loss of the Zener diode ZD 1 is increased, the size and heat generation of the component becomes a problem.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and has as its main object to control the advance angle without increasing the size of parts and without generating heat without providing an overvoltage protection circuit. DCCD that can supply a stable power supply voltage to the circuit
An object of the present invention is to provide an I-type ignition control device.

[0008]

According to the present invention, there is provided, in accordance with the present invention, an advance control circuit for controlling the ignition timing of an ignition device of an engine, and a generator provided in the ignition device and the advance control circuit. Or a DC-DC converter for transforming and supplying a voltage from a battery, wherein the DC-DC converter comprises a primary winding and a first coil for supplying power to the ignition device. 2 and winding and the transformer to have a second secondary winding for supplying power to the advance angle control circuit, the supply voltage to the first secondary winding of
Voltage generated in the first secondary winding to stably supply
DC- which controls the current flowing through the primary winding according to
A DC converter control circuit , wherein the two secondary windings are
Wherein the flyback connection is made to the primary winding, and a voltage smoothing circuit is interposed between the second secondary winding and the advance control circuit. Achieved by providing. In this way, the second
Is defined by the voltage on the first secondary winding side and the turn ratio between the two secondary windings.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to specific examples shown in the accompanying drawings.

FIG. 1 is a main part control circuit diagram of an ignition device for a motorcycle engine to which the present invention is applied. The AC generator 1 is connected to the battery 3 via the regulator 2 and to one end of a primary winding 6a in the transformer 6 of the DC-DC converter 5. This transformer 6
Has two secondary windings, a first secondary winding 6b is connected to the ignition device 8, and a second secondary winding 6c is a lead angle control CP.
Connected to U9. The other end of the primary winding 6a is D
The switching transistor T controlled by the C-DC converter control circuit 7 selectively connects to ground.

Here, the first winding 6a is
The secondary winding 6b and the second secondary winding 6c are both flybacks.
Connected. Specifically, the first secondary winding 6b and
The second secondary winding 6c is in the same direction as the second
Wound in the opposite direction to the next winding 6a, and flyback together
The direction of connection of the diodes to each winding so that the voltage is used,
The connection direction and the like of each element are set. In addition, the second 2
A rectifying diode D2 and a voltage smoothing circuit 10 including a resistor R2 and a capacitor C2 are interposed between the next winding 6c and the advance control CPU 9. Although this circuit is provided with an overvoltage protection zener diode ZD2, this can be omitted.

The operation of this circuit will be described below. First, when the normal battery 3 is functioning normally,
The voltage Vdd on the primary winding 6a side is, for example, about 12V, and the voltage Vc on the first secondary winding 6b side is about 230V at the maximum. Here, the turns ratio of the first secondary winding 6b and the second secondary winding 6c N2: N3 of 1: if set to 0.025, be Vca ≒ Vcc ≒ 5V after rectifying the VN3
It is Ru can.

Meanwhile, when the battery 3 ceases to function as a result of a malfunction, as shown in FIG. 2, the voltage Vdd of the primary winding 6a side is varied in the range of, for example, about 2V~34V, DC-DC converter By the control circuit 7, the first 2
The current flows to the primary winding 6a according to the voltage generated in the secondary winding 6b.
Since the current Vc is controlled, the voltage Vc on the first secondary winding 6b side does not change at about 230 V at the maximum. Turn ratio between the first secondary winding 6b and the second secondary winding 6c N2: N3 is 1:
Since VN3 is 0.025, Vca after rectifying VNＮVcc
Is about 5 V as in a normal battery. Also,
Although VN3 varies according to Vc, Vcc hardly varies due to the smoothing circuit 10.

[0014]

As described above, according to the present invention, DCDCI
A first secondary winding for supplying power to at ignition device to the DC-DC converter of the transformer of the ignition control apparatus of a system, and a second secondary winding for supplying power to advance control circuit 1 together
The flyback connection to the next winding and the interposition of a voltage smoothing circuit between the second secondary winding and the advancing control circuit allow components to be provided without providing an additional overvoltage protection circuit. It is possible to supply a stable power supply voltage to the advance control circuit without increasing the size and generating heat.

[Brief description of the drawings]

FIG. 1 is a main part circuit diagram of an ignition control device for a motorcycle engine to which the present invention is applied.

FIG. 2 is a time chart showing a voltage waveform in a main part of the control circuit of FIG. 1;

FIG. 3 is a main part circuit diagram of a conventional ignition control device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 AC generator 2 Regulator 3 Battery 4 Overvoltage protection circuit 5 DC-DC converter 6 Transformer 6a Primary winding 6b First secondary winding 6c Second secondary winding 7 DC-DC converter control circuit 8 Ignition device 9 Advance angle control CPU 10 Voltage smoothing circuit 16 Transformer 16a Primary winding 16b First secondary winding 16c Second secondary winding

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F02P 3/08 301 F02P 5/15 H02M 3/28 H02M 9/00

Claims (1)

(57) [Claims] An ignition control circuit for controlling an ignition timing of an ignition device of an engine, and a DC-DC converter for transforming and supplying a voltage from a generator or a battery to the ignition device and the advance control circuit. An ignition control device having a DC converter, wherein the DC-DC converter includes a primary winding and the ignition device.
To have a second secondary winding for supplying power to the first secondary winding and the advance angle control circuit for supplying power to
A transformer and a supply voltage to the first secondary winding should be supplied stably.
The primary winding according to a voltage generated in the first secondary winding.
DC-DC converter control circuit that controls the current flowing to the
And a road, the two secondary windings are both relative to the primary winding flyback
Is click connection, an ignition control device, characterized in that the smoothing circuit voltage is interposed between the second secondary winding and the advance angle control circuit.