JPS5932828Y2 - Spark generation circuit with battery consumption display function - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a battery-powered spark generation circuit that can be used for gas ignition, and in particular, when the battery used drops below a set reference voltage, the intensity of light emitted by the light emitting element is reduced to provide a user with a spark generator. Relating to a spark generating circuit that provides a warning.

Conventionally, as this type of spark generating circuit, a circuit as shown in FIG. 1 has been proposed.

In the figure, 1 is an oscillation circuit, 2 is a spark generating section, and 3 is a battery consumption display section.

The oscillation circuit 1 includes an oscillation transistor 4, an oscillation coil 5a directly connected to the collector of the transistor 4, and a resistor 6 inserted between the base of the transistor 4 and an intermediate tap remote from the collector side of the oscillation coil 5a. It consists of a feedback path, a DC battery 7 inserted between the intermediate tap near the collector side of the oscillation coil 5a, and the emitter of the transistor 4, and the current induced in the feedback path is positively fed back to the transistor 4 to generate blocking oscillation. It was designed to cause this to happen.

The spark generator 2 includes a secondary coil 5b that is electromagnetically coupled with the oscillation coil 5a and constitutes the oscillation transformer 5, a rectifying diode 8 connected in series to the coil 5b, a charging/discharging capacitor 9, and the low voltage side of the high voltage transformer 10. coil 10a,
A four-layer diode connected in parallel to a series circuit of a capacitor 9 and a coil 10a, and a pair of discharge electrodes 12a connected to a high voltage side coil 10b of a high voltage transformer 10.
, 12b.

In this spark generating section 2, alternating current induced in the secondary coil 5b by the oscillation of the oscillation circuit 1 is rectified by the diode 8 and then charged to the capacitor 9, and this charging voltage exceeds the breakover voltage of the 4-layer diode 11. , the diode 11 is turned on, the charge is discharged through the diode 11, and at this time, the current flowing through the coil 10a causes the coil 10
A high voltage is generated between the discharge electrodes 12a and 12b to generate sparks between the discharge electrodes 12a and 12b.

The battery consumption display section 3 includes a light emitting element (light emitting diode) 14 connected through a rectifier diode 13 between the side of the coil 5a opposite to the transistor 4 and the emitter of the transistor 4.

Since the amount of light emitted by the light-emitting element 14 is proportional to the applied voltage, the light-emitting element 14 whose voltage of the battery 7 is lower than a predetermined value becomes dim and issues a warning to the user.

However, the light emitting element 14 and the rectifying diode 13
Although the characteristics of the battery change with temperature and the amount of light emitted with respect to the battery voltage varies with temperature, the circuit described above does not take such temperature characteristics into account at all, and the circuit shown by the dotted line in Figure 3 does not take into account such temperature characteristics. It has poor temperature characteristics.

For example, when the ambient temperature rises, the forward voltage of the light emitting element 14 and diode 13 decreases, the light emission voltage decreases, and the amount of light emission for the same voltage increases, so that the battery voltage becomes higher than the voltage required for spark discharge. Even if it is lowered, the light emitting element 14 continues to emit bright light.

As a result, such circuits often lead to errors in the user's judgment regarding the degree of battery consumption. Therefore, the present invention improves the temperature characteristics by inserting a transistor in parallel with the light emitting element. An object of the present invention is to provide a spark generating circuit equipped with a battery consumption display section having good temperature characteristics.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 2 shows a spark generation circuit according to the present invention, in which oscillation circuit 1
Since the spark generating section 2 is the same as the conventional example shown in FIG. 1, the same reference numerals are given and the explanation thereof will be omitted.

In addition, the same reference numerals are given to other parts that are the same.

In the battery consumption display section 3', a temperature compensation transistor 15 is inserted in parallel with a light emitting element, such as a light emitting diode 14.

This transistor 15 is preferably made of the same material as the light emitting element 14, that is, in the case of a silicon light emitting diode, a silicon transistor is used, and the collector of the transistor 15 is connected to the light emitting diode 14 through a current limiting resistor 16. On the anode side, the emitter is directly connected to the cathode side, and the collector and base are shorted.

As the diode 13, a diode with a long reverse recovery time Trr, for example, 1.0 μs or more is used.

A current limiting resistor 17 is inserted in series with the diode 13.

Further, a diode 18 is inserted in parallel with the light emitting diode 14 so as to have a polarity opposite to that of the light emitting diode 14.

Next, the operation of the battery consumption display section 3' of this embodiment will be mainly described.

When the battery 7 is turned on by a switch (not shown), the voltage of the battery 7 is boosted by the coil 5a, rectified by the diode 13, and applied to both ends of the light emitting element 14 and the transistor 15, causing the light emitting element 14 to have its forward resistance. A current flows proportionally, and light is emitted depending on the magnitude of the current, and unless the battery voltage is extremely low, the transistor 15 is turned on and current flows through it.

The user determines the magnitude of the battery voltage according to the brightness of the light emitting element 14.

When the ambient temperature rises, the light emitting voltage of the light emitting element 14 decreases and the current flowing through it increases, and the forward voltage of the diode 13 also decreases, causing the current to further increase and the amount of light emitted to increase. However, as the temperature of the transistor 15 rises, its current amplification factor h
fe increases, the current flowing through the transistor 15 increases,
As a result, the current flowing through the light emitting element 14 is suppressed to an amount close to that before the temperature rises, and is not significantly affected by temperature changes.

According to this example, temperature characteristics as shown by the solid line in FIG. 3 were obtained.

This characteristic indicates the rate of change in voltage with respect to temperature change, based on the voltage required to obtain the amount of light emission at an ambient temperature of 20°C.

This embodiment improves the overall temperature characteristics by making good use of the temperature characteristics of the light emitting voltage of the light emitting element, the forward voltage of the diode, and the amplification factor of the transistor.

Furthermore, the oscillation circuit 2 performs blocking oscillation, and its oscillation frequency is usually high, on the order of 20 KHz, and the diode 1
3 is inserted to block the negative component of the oscillation output, but according to this embodiment, the diode 13 has a reverse recovery time T
Since a filter with a large rr and poor high frequency characteristics is used, a certain amount of negative components also pass through.

By passing the negative component to some extent and applying it to the light emitting element 14 in this way, the degree of light emission of the light emitting element 14 with respect to the battery voltage changes more linearly.

On the other hand, a diode 18 is inserted in order to prevent a large reverse voltage from being applied to the light emitting element 14 and destroying it due to the application of a negative component.

As explained above, the present invention successfully offsets the temperature characteristics of the light emitting element with the temperature characteristics of the transistor.
The overall temperature characteristics of the battery consumption display section of the spark generation circuit have been improved, making it possible to accurately grasp the degree of battery consumption, preventing unnecessary gas from blowing out due to misfired sparks at the time of ignition, and reducing the internal resistance of the battery. This has a very large practical effect in that it can prevent damage caused by the increase in the amount of water.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing a conventional spark generating circuit, FIG. 2 is a circuit diagram showing an embodiment of the spark generating circuit according to the present invention, and FIG. 3 is a diagram showing temperature characteristics of the conventional example and this embodiment.

Claims (1)

[Scope of utility model registration request] an oscillation circuit including at least an oscillation coil, an oscillation transistor, and a DC battery, and a spark generation section that generates sparks based on a voltage induced in a secondary coil electromagnetically coupled to the oscillation coil, the oscillation coil A spark that is coupled to an oscillation transistor, has a light emitting element connected to both ends of the coupled oscillation coil and the oscillation transistor, and has a transistor inserted in parallel with the light emitting element, and has a battery consumption display function. generation circuit.