JP7524756B2 - Ignition device control system, device and program - Google Patents

Description

The present invention relates to an ignition device control system, device, and program.

Spark plugs installed in internal combustion engines of automobiles and the like are required to have improved ignition performance and reduced electrode wear.
As described in Patent Document 1, it is known that ignition performance changes depending on the mounting angle position of the outer electrode inside the combustion chamber, and experimental data and the like show that ignition performance can be improved by adjusting the mounting angle position of the spark plug so that the outer electrode is perpendicular to the direction from the intake valve side to the exhaust valve side. Patent Document 1 discloses a configuration in which the outer electrode and the plug body are formed separately and the outer electrode is disposed inside the combustion chamber. As a result, the outer electrode is always disposed in a direction that does not interfere with the flow of the mixture inside the combustion chamber, regardless of the mounting angle position around the axis of the plug body, and therefore the ignition performance of the spark plug can be improved.

JP 2000-357578 A

However, in Patent Document 1, a special ignition plug is used in which the outer electrode and the plug body are separate, and the outer electrode must be installed inside the combustion chamber separately from the spark plug. This increases the cost of installing the ignition plug and makes it difficult to maintain the outer electrode against wear, etc.
Furthermore, although the technique disclosed in Patent Document 1 can improve the ignition performance of the spark plug, it cannot suppress electrode wear of the spark plug.

The present invention was made in consideration of these circumstances, and aims to reduce electrode wear on spark plugs without increasing the cost of installing them and compromising maintainability.

The ignition control system of the present invention is an ignition control system that controls an ignition device that includes an ignition plug having a center electrode and an outer electrode arranged to face the center electrode, and an ignition coil that applies a voltage to the ignition plug, and is characterized by including a detection device that detects the orientation of the outer electrode of the ignition plug when installed in an internal combustion engine, and a control device that sets the current flow time of the ignition coil based on the orientation of the outer electrode detected by the detection device, and controls the ignition coil according to the set current flow time.

The present invention makes it possible to reduce electrode wear on spark plugs without increasing the cost of installing them and compromising ease of maintenance.

1 is a diagram showing a configuration of a control system for an ignition device according to an embodiment; FIG. 2 is a diagram illustrating a configuration example of an ignition coil. FIG. 4 is a diagram showing an example of the relationship between the orientation of the outer electrode of the ignition plug and the required voltage.

An ignition device control system according to one embodiment of the present invention is an ignition device that controls an ignition device including an ignition plug having a center electrode and an outer electrode arranged opposite the center electrode, and an ignition coil that applies voltage to the ignition plug, and includes a detection device that detects the orientation of the outer electrode of the ignition plug when installed in an internal combustion engine, and a control device that sets a current flow time for the ignition coil based on the orientation of the outer electrode detected by the detection device, and controls the ignition coil in accordance with the set current flow time.
As a result, for example, when the required voltage is reduced due to the orientation of the outer electrode, the time that the ignition coil is energized can be shortened. By shortening the time that the ignition coil is energized, the discharge time at the spark plug is shortened, which reduces the occurrence of re-discharge in the spark plug and reduces electrode wear of the spark plug. In addition, instead of a special spark plug in which the outer electrode and the plug body are separate as in Patent Document 1, a spark plug in which a center electrode and an outer electrode are provided on the plug body can be used, which avoids the increase in costs for installing the spark plug and does not impair maintainability.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a diagram showing the configuration of a control system for an ignition device according to an embodiment.
An ignition device for an internal combustion engine 300 of an automobile or the like includes an ignition plug 100 installed in the internal combustion engine 300 , and an ignition coil 200 that applies a voltage to the ignition plug 100 .

The ignition plug 100 comprises a plug body 101, a center electrode 102 provided in the center of the tip of the plug body 101, and an L-shaped outer electrode 103 provided on the side of the tip of the plug body 101 and arranged to face the center electrode 102. The ignition plug 100 is installed in each cylinder of the internal combustion engine 300, and is arranged so that the center electrode 102 and the outer electrode 103 protrude into the combustion chamber 301.

The ignition coil 200 is connected to the terminal 104 of the plug body 101 and applies a voltage to the spark plug 100. FIG. 2 shows an example of the configuration of the ignition coil 200. The ignition coil 200 includes a primary coil 201 to which power is supplied from the battery VB, and a secondary coil 202 connected to the spark plug 100. When the igniter 203 is turned on, a current flows through the primary coil 201, and when the igniter 203 is turned off, the current to the primary coil 201 is stopped. When the current to the primary coil 201 is stopped, a high voltage is generated in the secondary coil 202 by electromagnetic induction. This generates a spark discharge between the electrodes 102, 103 of the spark plug 100, igniting the mixture in the combustion chamber 301.

When the spark plug 100 is installed in the internal combustion engine 300, the direction of the outer electrode 103 is set to a direction perpendicular to the direction from the intake valve side to the exhaust valve side, that is, perpendicular to the flow direction of the gas (air-fuel mixture) as shown in state (a) of Fig. 3 (hereinafter referred to as the reference direction). This makes it possible to improve the ignition performance of the spark plug 100, as described in Patent Document 1.
However, due to component tolerances, the orientation of the outer electrode 103 may deviate from the reference direction within a predetermined range (approximately ±25°) as shown in states (b) and (c) of FIG.

Here, FIG. 3 shows an example of the relationship between the orientation of the outer electrode 103 and the required voltage. As shown in FIG. 3, it has been found from experiments that the required voltage of the spark plug 100 changes depending on the orientation of the outer electrode 103. The required voltage is the voltage required to generate a spark discharge between the electrodes 102 and 103 of the spark plug 100, in other words, the secondary voltage to be generated in the secondary coil 202 of the ignition coil 200. Point 31 indicates the required voltage when the orientation of the outer electrode 103 is in the reference direction. Points 32 and 33 indicate the required voltage when the orientation of the outer electrode 103 is deviated by ±25° from the reference direction. When the orientation of the outer electrode 103 deviates from the reference direction, the required voltage decreases according to the amount of deviation. This is thought to be due to the way gas hits the electrodes 102 and 103 in the combustion chamber 301.

When the required voltage of the spark plug 100 drops while the secondary voltage of the ignition coil 200 remains unchanged, residual energy is more likely to occur in the spark plug 100, and the discharge time of the spark plug 100 becomes longer. When the discharge time of the spark plug 100 becomes longer, the spark plug 100 becomes more likely to re-discharge (also called restrike), and the electrodes of the spark plug 100 become more likely to wear out. Spark plug re-discharges include re-discharges due to the blowing out of the discharge extension between the electrodes 102, 103 (discharge extension is broken and then reconnected due to gas flow) and re-discharges due to short circuits (discharge extension is broken and then reconnected).

Therefore, in this embodiment, as described below, in order to suppress electrode wear of the spark plug 100, the current flow time of the ignition coil 200 is set based on the orientation of the outer electrode 103 of the spark plug 100 when installed in the internal combustion engine 300, and the ignition coil 200 is controlled in accordance with the set current flow time.
In order to realize this control, the control system for the ignition device includes a control device 1 and a detection device 2, as shown in FIG.

The detection device 2 detects the orientation of the outer electrode 103 of the spark plug 100 when it is installed in the internal combustion engine 300. The detection device 2 is configured such that, for example, the spark plug 100 includes a transmitter 2a that transmits a signal corresponding to the orientation of the outer electrode 103, and the ignition coil 200 includes a receiver 2b that receives the signal from the transmitter 2a. Note that the detection device 2 may be any device capable of detecting the orientation of the outer electrode 103 of the spark plug 100, and its specific configuration is not limited. For example, it may be of either a contact type or a non-contact type, and may be configured as a magnetic detection device, an optical detection device, or the like.

The control device 1 includes a memory unit 1a, an acquisition unit 1b, a current flow time setting unit 1c, and a current flow control unit 1d, and sets the current flow time of the ignition coil 200 for each cylinder based on the orientation of the outer electrode 103 detected by the detection device 2, and controls the ignition coil 200 according to the set current flow time.

The memory unit 1a stores a map that defines the correction coefficients used by the current flow time setting unit 1c to set the current flow time of the ignition coil 200. Table 1 shows an example of a map that defines the correction coefficients. The current flow time of the ignition coil 200 set assuming that the orientation of the outer electrode 103 is in the reference direction is set as the reference current flow time T. The correction coefficient is a coefficient that is multiplied by the reference current flow time T. When the orientation of the outer electrode 103 is in the reference direction, the correction coefficient is "1", and the reference current flow time T is set as it is. When the orientation of the outer electrode 103 deviates from the reference direction, the correction coefficient becomes a value smaller than "1", and the larger the deviation from the reference direction, the smaller the correction coefficient becomes, such as "0.99", "0.98", or "0.95". In other words, the larger the deviation from the reference direction, the shorter the current flow time T is set.

The acquisition unit 1b acquires information on the orientation of the outer electrode 103 detected by the detection device 2.

The current conduction time setting unit 1c sets a current conduction time of the ignition coil 200 based on the information on the orientation of the outer electrode 103 acquired by the acquisition unit 1b. In detail, the current conduction time setting unit 1c determines a correction coefficient from the map in the storage unit 1a based on the information on the orientation of the outer electrode 103 acquired by the acquisition unit 1b, and sets the current conduction time by multiplying the correction coefficient by a reference current conduction time T. As described above, the greater the deviation from the reference direction, the shorter the current conduction time that is set than the reference current conduction time T.
In the example of Table 1, the correction coefficient is "0.99" when the deviation from the reference direction (angle with respect to the reference direction) is ±5°, "0.98" when it is ±15°, and "0.95" when it is ±25°, but if the deviation from the reference direction is α, for example, the correction coefficient may be "0.99" when 0°<α≦5° and -5°≦α<0°, "0.98" when 5°<α≦15° and -15≦α<-5°, and "0.95" when 15°<α≦25° and -25≦α<-15°. Alternatively, when the deviation α from the reference direction is a value other than 0°, ±5°, ±15°, and ±25°, the correction coefficient may be determined by performing an interpolation calculation using the correction coefficients at 0°, ±5°, ±15°, and ±25°. In the example of Table 1, the correction coefficients are set when the deviation from the reference direction is ±5°, ±15°, and ±25°, but the correction coefficients may be set for smaller angles.

The current control unit 1d controls the ignition coil 200 according to the current flow time set by the current flow time setting unit 1c. In detail, the current control unit 1d turns on/off the igniter 203 of the ignition coil 200 according to the current flow time set by the current flow time setting unit 1c, thereby performing current flow for the current flow time set by the current flow time setting unit 1c.

The acquisition of information on the orientation of the outer electrode 103 by the acquisition unit 1b and the setting of the current flow time by the current flow time setting unit 1c may be performed, for example, when the engine is started, and the current flow time set by the current flow time setting unit 1c may be stored in a storage medium. Then, the current flow control unit 1d executes current flow for the current flow time stored in the storage medium.

As described above, the control device 1 sets the current-carrying time of the ignition coil 200 when the orientation of the outer electrode 103 is in the reference direction as the reference current-carrying time T, and corrects the reference current-carrying time T based on the orientation of the outer electrode 103 detected by the detection device 2 to set the current-carrying time. Specifically, when the orientation of the outer electrode 103 detected by the detection device 2 deviates from the reference direction, the current-carrying time is made shorter than the reference current-carrying time T. Then, the control device 1 controls the ignition coil 200 in accordance with the set current-carrying time.
As a result, when the orientation of the outer electrode 103 deviates from the reference direction and the required voltage of the spark plug 100 drops, the energization time of the ignition coil 200 can be made shorter than the reference energization time. By shortening the energization time of the ignition coil 200, the discharge time of the spark plug 100 is shortened, which makes it possible to suppress the occurrence of re-discharge of the spark plug 100 and to suppress electrode wear of the spark plug 100. Furthermore, since the secondary voltage of the secondary coil 202 tends to drop due to the shortening of the energization time of the ignition coil 200, it is possible to match the characteristic of the spark plug 100, which requires a lower voltage.

In addition, the spark plug 100 is not a special spark plug in which the outer electrode and plug body are separate as in Patent Document 1, but rather an ignition plug in which the center electrode and outer electrode are provided on the plug body, which avoids the increased cost of installing the spark plug and does not impair maintainability.

The control device 1 is configured by a computer device equipped with, for example, a CPU, ROM, RAM, etc., and the functions of the acquisition unit 1b, the current flow time setting unit 1c, and the current flow control unit 1d are realized by the CPU executing a predetermined program stored in, for example, the ROM. For example, the control device 1 may be realized as part of the functions of a control unit mounted on the vehicle.

Although the embodiments of the present invention have been described above in detail with reference to the drawings, each embodiment merely shows a specific example of the implementation of the present invention. The technical scope of the present invention is not limited to each embodiment. Various modifications of the present invention are possible without departing from the spirit of the present invention, and these modifications are also included in the technical scope of the present invention.
The present invention can also be realized by supplying software (programs) to a system or device via a network or various storage media, and having the computer of the system or device read and execute the programs.

1: Control device, 1a: Memory unit, 1b: Acquisition unit, 1c: Current flow time setting unit, 1d: Current flow control unit, 2: Detection device, 100: Spark plug, 101: Plug body, 102: Center electrode, 103: Outer electrode, 200: Ignition coil, 300: Internal combustion engine

Claims (6)

A control system for an ignition device that controls an ignition device including an ignition plug having a center electrode and an outer electrode arranged to face the center electrode, and an ignition coil that applies a voltage to the ignition plug,
a detection device that detects the orientation of the outer electrode of the spark plug when the spark plug is installed in an internal combustion engine;
a control device that sets a current flow time of the ignition coil based on the orientation of the outer electrode detected by the detection device, and controls the ignition coil in accordance with the set current flow time. The control device is characterized in that the control device sets the ignition coil current conduction time, which is set assuming that the orientation of the outer electrode is in a reference direction, as a reference current conduction time, and corrects the reference current conduction time based on the orientation of the outer electrode detected by the detection device to set the current conduction time. The ignition device control system according to claim 2, characterized in that the control device shortens the current flow time to be shorter than the reference current flow time when the orientation of the outer electrode detected by the detection device deviates from the reference direction. The ignition control system according to claim 2 or 3, characterized in that the reference direction is a direction perpendicular to the direction in which the outer electrode faces from the intake valve side to the exhaust valve side. A control device for controlling an ignition device including an ignition plug having a center electrode and an outer electrode arranged to face the center electrode, and an ignition coil that applies a voltage to the ignition plug,
an acquisition means for acquiring information on the orientation of the outer electrode of the spark plug when the spark plug is installed in an internal combustion engine;
a current supply time setting means for setting a current supply time of the ignition coil based on the information on the orientation of the outer electrode acquired by the acquisition means;
and a current control means for controlling the ignition coil in accordance with the current supply time set by the current supply time setting means. A program for controlling an ignition device including an ignition plug having a center electrode and an outer electrode arranged to face the center electrode, and an ignition coil that applies a voltage to the ignition plug,
an acquisition means for acquiring information on the orientation of the outer electrode of the spark plug when the spark plug is installed in an internal combustion engine;
a current supply time setting means for setting a current supply time of the ignition coil based on the information on the orientation of the outer electrode acquired by the acquisition means;
a program for causing a computer to function as a current control means for controlling the ignition coil in accordance with the current time set by the current time setting means;

Images