JPS63150466A - Noncontact ignition device - Google Patents

Abstract

PURPOSE:To achieve positive burning when mixture becomes lean at acceleration by activating a DC.DC converter adapted to generate intermediate/high voltage for holding discharge current flowing across electrodes at an ingnition plug, only when acceleration is detected. CONSTITUTION:During normal running, a predetermined signal from an ignition circuit 19 is entered in a switching element 6 to switch an ignition coil 4 so as to generate secondary voltage at an ignition plug 2. During acceleration, a one-shot multicircuit composed of resistors 7 to 9, a capacitor 10 and a comparator 11 is activated only for a predetermined period of time so as to obtain a Hi output from the comparator 11. A signal outputted from a control circuit 18 through a starting circuit 17 is entered in a switching element 5 to activate a step up transformer 3 only for a predetermined period of time. Thus increased voltage is added to the secondary voltage at the ignition coil 4 to perform high-energy ignition.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a non-contact ignition device, and particularly to a non-contact ignition device for an internal combustion engine equipped with a DC/DC converter.

[Conventional technology]

As described in Japanese Patent Application Laid-open No. 59-150977, conventional devices perform high-energy ignition only during idle and low-speed rotation, with the aim of stabilizing the idle rotation speed and improving fuel efficiency. However, no consideration was given to increasing the energy at the time of acceleration.

[Problem that the invention seeks to solve]

The above conventional technology does not take into consideration the fact that the air-fuel mixture in the cylinder becomes lean during acceleration, and there is a problem in that combustion becomes unstable during the time it takes for the air-fuel mixture to become rich, resulting in poor acceleration and no increase in output. Ta.

The purpose of the present invention is to improve acceleration response and increase output by ejecting high-energy sparks to ensure combustion when the air-fuel mixture in the cylinder becomes lean due to turning on the accelerator during acceleration.

[Means for solving problems]

The purpose of the above is to detect the acceleration signal input from the control unit, and to output the data for a certain period of time from the detected timing.
This is achieved by operating a C-DC converter to cause repeated discharges and high-energy ignition.

[Effect]

When the accelerator is turned on, the control unit outputs an acceleration signal. A circuit is provided that outputs a HI signal only for a certain period of time after detecting an acceleration signal. The acceleration response can be improved and the output can be increased by operating the DC-DC converter only for a certain period of time during which this HI signal is being output to perform a single discharge.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. 1 is a battery, 2 is a spark plug, 3 is a step-up transformer, 4 is an ignition coil, and 5 and 6 are switching elements. 7, 8, 9, 12, 13° 14.15 is a resistor, 1o is a capacitor, and 11 is a comparator, forming a one-shot multi-circuit for determining the operating time of the DC-DC converter. 16 is a DC-DC converter, 1
7 is an oscillation circuit, 18 is a control circuit, and 19 is an ignition circuit. Terminal A is a terminal for inputting an acceleration signal from the control unit.

During normal operation, a signal as shown in FIG. 2(a) is input from the ignition circuit 19 to the switching element 6.

The ignition coil 4 is switched, the ignition plug 2 is ignited, and a secondary voltage as shown in Fig. 2g is generated.

Also, via the control circuit 18 and the oscillation circuit 17, as shown in FIG.
During normal operation, the output Vc of the comparator 11 becomes Lo. sVc is Lo, so the Vb signal is pulled in. , switching element 5 does not operate,
During acceleration operation, when the accelerator is turned on, the acceleration signal shown in FIG. 2(c) is input from the control unit to the A terminal.

When this acceleration signal is input, the one-shot multi-circuit operates for a certain period of time t, and outputs a HI times signal to Vc.

Since Vc becomes HI, the Vb signal is transferred to switching element 5.
, and the step-up transformer 3 is operated for a certain period of time t. This boosted voltage is superimposed on the secondary voltage generated by one ignition coil 4 to perform high-energy ignition as shown at h in FIG. 2.

According to this embodiment, when the fuel is lean immediately after the accelerator is turned on during acceleration, high-energy sparks are emitted for a certain period of time.
This has the effect of improving combustion efficiency and acceleration.

〔Effect of the invention〕

According to the present invention, when the air-fuel mixture in the cylinder during acceleration is lean, high-energy ignition can be performed to improve combustion efficiency, resulting in improved acceleration response and high output.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of one embodiment of the present invention, and FIG.
FIG. 3 is a diagram showing waveforms of various parts of the circuit shown in the figure. DESCRIPTION OF SYMBOLS 1... Battery, 2... Spark plug, 3... Step-up transformer, 4... Ignition coil, 5, 6... Switching element, 7.8, 9, 12, 13, 14, 15.・・・
Resistor, 10... Capacitor, 11... Comparator, 16... Boost circuit, 17... Oscillation circuit, 18...
・Control circuit.

Claims (1)

[Claims] 1. An ignition device that generates a high voltage pulse necessary to break the insulation between the spark plug electrodes, and a discharge current that flows between the spark plug electrodes after the ignition device breaks the insulation between the spark plug electrodes. Furthermore, in an ignition system equipped with a DC/DC converter that generates medium and high voltage to maintain the voltage, the acceleration state is detected and the DC/DC converter is operated for a certain period of time.
A non-contact ignition device characterized by high-energy ignition.