JP2001349542A - Ignition device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ignition device capable of reliably generating sparks throughout a long period. SOLUTION: An ignition energy concentrating part 11 is formed at the tip part of an ignition electrode 10. And, the ignition energy concentration part 11 is formed in a linear state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ignition device, and more particularly to a spark ignition device used for a combustion device.

[0002]

2. Description of the Related Art In boilers and incinerator combustion devices,
A spark ignition device is used as an ignition device for a combustion device. An example of a spark ignition device in the combustion device will be described with reference to FIGS.

[0003] First, the combustion apparatus 1 will be described. The combustion device 1 is a premix gas burner, and includes a cylindrical burner main body 2 and a nozzle member 3. The nozzle member 3 is formed with a large-diameter premixed gas ejection hole (hereinafter, referred to as a “first ejection hole”) 4 at a central portion thereof, and a small diameter so as to surround the first ejection hole 4. The plurality of premixed gas ejection holes (hereinafter, referred to as “second ejection holes”) 5 are formed.

Next, the ignition device 6 will be described. In this example, the ignition device 6 uses a part of the combustion device 1 as an electrode. That is, the ignition device 6 includes an ignition electrode 7 disposed inside the burner main body 2.
And a voltage applying means 8 connected between the ignition electrode 7 and the burner main body 2. The tip of the ignition electrode 7 is disposed substantially coaxially with the nozzle member 3 with an appropriate gap between the tip of the ignition electrode 7 and the inner peripheral edge of the first ejection hole 4. The ignition electrode 7 is provided so as to be electrically insulated from the burner main body 2. Therefore, in the ignition device 6, the nozzle member 3 functions as an electrode paired with the ignition electrode 7.

Next, the operation of igniting the combustion device 1 by the ignition device 6 will be described. First, an ignition voltage is applied between the ignition electrode 7 and the burner main body 2 by the voltage applying means 8, and a voltage is applied between the tip of the ignition electrode 7 and the inner peripheral edge of the first ejection hole 4. Generate a spark. In this state, a premixed gas is supplied to the burner main body 2, and the premixed gas is ejected from the first ejection holes 4 and the second ejection holes 5. Then, the premixed gas ejected from the first ejection holes 4 is ignited by the energy of the spark and starts burning. Further, the combustion of the premixed gas from the first ejection holes 4 ignites the premixed gas from each of the second ejection holes 5.

In the igniter 6, when the ignition voltage applied between the burner main body 2 and the ignition electrode 7 is reduced, a spark is less likely to be generated, and the combustion device 1 cannot be ignited. Sometimes. The reason for this is that the ignition electrode 7 has a round bar shape and the periphery of the tip is circular, so that the ignition energy is distributed over the entire periphery of the circle at the tip of the ignition electrode 7.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide an ignition device capable of reliably generating a spark.

[0008]

Means for Solving the Problems The present invention has been made to solve the above-mentioned problems, and the invention according to claim 1 is characterized in that an ignition energy concentration portion is formed at the tip of an ignition electrode. And

Further, the invention according to claim 2 is characterized in that the ignition energy concentration portion is formed in a linear shape.

[0010]

Next, an embodiment of the present invention will be described. The ignition device according to the present invention can be suitably implemented in a spark type ignition device. The ignition device according to the present invention can be suitably applied particularly as an ignition device for a combustion device.

In the ignition device according to the present invention, an ignition energy concentration portion is formed at the tip of the ignition electrode. The ignition energy concentration unit is a unit that concentrates ignition energy by applying an ignition voltage. Therefore, in the ignition device, by forming the ignition energy concentration portion in the ignition electrode, it is possible to reliably generate a spark in the ignition energy concentration portion.
By forming the ignition energy concentrating portion in a linear shape, the ignition energy concentrating portion is less likely to be worn, so that a spark can be stably and reliably generated for a long period of time.

The ignition energy concentrating portion can be formed by forming the ignition electrode in the following shape. First, by forming the tip portion of the ignition electrode in a flat shape, it is possible to form ignition energy concentration portions along the axial direction of the ignition electrode at two locations in the circumferential direction of the ignition electrode. Further, by forming the cross-sectional shape of the front end portion of the ignition electrode into an arcuate shape, it is possible to form ignition energy concentration portions at two locations in the circumferential direction of the ignition electrode.

[0013] The ignition energy concentrating portion may be formed at one or three or more locations on the ignition electrode. First, in the case where there is only one location, the ignition energy concentrating portion can be formed by shaping one location in the cross-sectional shape of the tip of the ignition electrode, for example, into a sector shape. Next, in the case of three or more locations, the ignition energy concentrating portion can be formed by making the cross-sectional shape of the tip of the ignition electrode into a polygonal shape such as a triangular shape or a quadrangular shape. . Here, since the number of places where the ignition energy concentration portion is formed increases as the ignition energy per one portion of the ignition energy concentration portion decreases, it is preferable that the number is 6 or less,
More preferably, the number is four or less.

Further, the ignition energy concentrating portion can form the ignition energy concentrating portion by forming a predetermined number of projections radially at the tip of the ignition electrode. Further, the ignition energy concentration portion can be provided not only at the tip of the ignition electrode but also over the entire ignition electrode. Further, the direction in which the ignition energy concentration portion is linearly formed may be the axial direction of the ignition electrode or the circumferential direction of the ignition electrode.

Next, an example of application of the ignition device to a combustion device will be described. First, when the ignition electrode is arranged inside or outside the combustion device, and a spark is generated between the combustion device and the ignition electrode, the distance between the ignition energy concentration portion and the combustion device is reduced. To be placed. Here, when the combustion device has a cylindrical shape and the ignition electrode is disposed inside the combustion device, the ignition electrode can be disposed substantially coaxially with the combustion device.

Next, in the case of a configuration in which two ignition electrodes are arranged inside or outside the combustion device and a spark is generated between the ignition electrodes to ignite the combustion device, The ignition energy concentration portions are arranged so as to face each other. Here, when the ignition energy concentrating portions are formed in a plurality of places on each of the ignition electrodes, it is preferable that one ignition energy concentrating portion in each of the ignition electrodes is arranged so as to face each other. When the ignition electrodes are arranged in this manner, even if one ignition energy concentration part is worn out and a spark is unlikely to occur, the ignition electrodes are rearranged so as to face the other ignition energy concentration parts. As a result, the spark can be reliably generated, and as a result, the life of the ignition electrode can be extended.

[0017]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional side view showing a first embodiment of an ignition device according to the present invention, and FIG.
FIG. The first embodiment shown in FIGS. 1 and 2 is a first application example in which the first embodiment is applied to the combustion device shown in FIGS. 17 and 18. In FIGS. 17 and 18 denote the same members, and a detailed description thereof will be omitted.

In FIG. 1, the ignition device 9 is of a type in which a part of the combustion device 1 is used as an electrode, as described above.
The ignition electrode 10 constituting the ignition device 9 includes:
Ignition energy concentrating portions 11, 11 are formed at two places. These ignition energy concentration portions 11 are formed by crushing the tip of the ignition electrode 10 into a flat shape by press working. That is, when the flat portion 12 is formed at the tip of the ignition electrode 10, the flat portion 1 is formed.
2 has a narrow portion 13 and a wide portion 14, and the narrow portion 13 functions as each of the ignition energy concentration portions 11. . Further, in the ignition electrode 10, since the flat portion 12 is formed over a predetermined length from the tip of the ignition electrode 10, each of the ignition energy concentration portions 11
Are formed linearly in the axial direction of the ignition electrode 10.

Further, since the flat portion 12 is formed by crushing the tip of the ignition electrode 10 by press working, the width dimension A of the wide portion 14 is equal to that of the original round bar-shaped portion. It is larger than the diameter B.
For this reason, the interval C between the inner peripheral edge of the first ejection hole 4 and the conventional ignition electrode 7 having a round bar shape at the tip is smaller.

Next, the operation of igniting the combustion device 1 by the ignition device of the first embodiment will be described. First,
Similarly to the above, the voltage application means 8 applies an ignition voltage between the ignition electrode 10 and the burner main body 2. Then, in the ignition electrode 10, since the ignition energy by the voltage applying means 8 is concentrated on each of the ignition energy concentrating portions 11, each of the ignition energy concentrating portions 11
A spark is generated between the first ejection hole 4 and the inner peripheral edge of the first ejection hole 4. Further, since the interval C between each of the ignition energy concentration portions 11 and the inner peripheral edge of the first ejection hole 4 is narrow, the spark is reliably generated even if the ignition voltage required for the spark is low. In this state, when the premixed gas is supplied to the burner main body 2, the premixed gas is ejected from the first ejection holes 4 and the second ejection holes 5, and the premixed gas is reliably ignited by the energy of the spark. Will be done.

Therefore, the ignition electrode 9 of the first embodiment
According to the above, by forming each of the ignition energy concentrating portions 11, the spark is generated only at each of the ignition energy concentrating portions 11 in the ignition electrode 9, so that the spark is reliably generated, and the combustion device 1 can be reliably performed. Further, since each of the ignition energy concentration portions 11 is formed in a linear shape, the ignition energy concentration portions 11 are less likely to be worn by sparks.
Spark can be reliably generated over a long period of time.

Further, according to the ignition electrode 9 of the first embodiment, since the distance C between each of the ignition energy concentration portions 11 and the inner peripheral edge of the first ejection hole 4 is narrow, the voltage application means Even if the ignition voltage applied between the ignition electrode 10 and the burner main body 2 is reduced due to fluctuations in the power supply voltage to the burner 8, a spark is reliably generated, and ignition to the combustion device 1 is ensured. Can be done.

Next, a second embodiment and a third embodiment of the ignition device according to the present invention will be described with reference to FIGS. Here, in FIGS. 3 to 6 showing the second embodiment and the third embodiment, only the tip of the ignition electrode 10 is shown.

First, in the second embodiment shown in FIG. 3, the projections 15 are provided at the tip of the ignition electrode 10 to form the ignition energy concentration portions 11. In the second embodiment, the projections 15 are provided on the peripheral surface of the distal end portion of the ignition electrode 10 on both sides in the diameter direction of the ignition electrode 10. In addition, each of the projections 15
Is composed of a member separate from the ignition electrode 10 and is connected to the ignition electrode 10 by welding or brazing.
It is also preferable to form the respective ignition energy concentrating portions 11 integrally with each other according to the implementation.

When the ignition electrode 10 of the second embodiment is applied to the same combustion apparatus 1 as that of the first embodiment, each of the projections 15 causes the inner peripheral edge of the first ejection hole 4 to be connected to each of the ignition energy concentration portions. Since the distance C from the ignition device 11 is narrow, even if the ignition voltage by the voltage application means 8 is reduced, a spark can be reliably generated, and the combustion device 1 can be reliably ignited.

Here, in the second embodiment, each of the ignition energy concentrating portions 11 is formed by providing each of the projections 15 at the tip of the ignition electrode 10, as shown in FIG. In addition, two points at the front end of the peripheral surface of the ignition electrode 10 are plastically worked into a protruding shape, so that two ignition energy concentration parts 11 can be formed, and as shown in FIG. 4 at the end of the peripheral surface of 10
By forming the portions plastically in a protruding shape, four ignition energy concentration portions 11 can be formed.

Next, in the third embodiment shown in FIG. 6, the tip of the ignition electrode 10 is pressed or pulled out so that the cross section of the tip of the ignition electrode 10 has a substantially equilateral triangular shape. By performing plastic working such as working, the ignition energy concentrating portions 11, 11, 1 in the axial direction of the ignition electrode 10 are respectively provided at three radial positions of the ignition electrode 10.
1 are formed.

In the ignition electrode 10 of the third embodiment, similarly to the first embodiment, the respective ignition energy concentration portions 11 are formed by subjecting the tip of the ignition electrode 10 to plastic working. Therefore, the distance from the central axis of the ignition electrode 10 to each of the ignition energy concentrating portions 11 is longer than the diameter B of the original round bar-shaped portion. Therefore, by applying to the combustion device 1 similar to that of the first embodiment, the interval C between the inner peripheral edge of the first ejection hole 4 and each of the ignition energy concentration portions 11 can be narrowed. Therefore, even if the ignition voltage is reduced, the spark can be reliably generated, and the combustion device 1 can be reliably ignited.

Further, the ignition energy concentrating unit 11
Instead of providing the protrusion 15 at the tip of the ignition electrode 10 or forming the tip of the ignition electrode 10 by plastic working, the tip of the ignition electrode 10 is subjected to machining such as cutting or grinding. Can be formed by About these 4th Example-6th Example, FIG.
A description will be given based on FIG. Here, in FIGS. 7 to 11 showing the fourth to sixth embodiments, only the tip of the ignition electrode 10 is shown.

First, in the fourth embodiment shown in FIG. 7, the flattened portion 12 is formed at the tip of the ignition electrode 10 by removing both side surfaces of the ignition electrode 10, and the ignition energy concentration portions 11 are formed. Is formed.

Next, in the fifth embodiment shown in FIG. 8, the tip of the ignition electrode 10 has a predetermined length so that the cross section of the tip of the ignition electrode 10 has an arcuate shape. In other words, two ignition energy concentration portions 11 are formed on both sides of the ignition electrode 10 in the radial direction along the axis of the ignition electrode 10. In the fifth embodiment, the tip of the ignition electrode 10 is substantially uniformly removed along the axial direction of the ignition electrode 10. However, as in the modification shown in FIG. A part of the tip of the ignition electrode 10 can be obliquely deleted, and an ignition energy concentrating portion 11 inclined with respect to the axial direction of the ignition electrode 10 can be formed at the tip of the ignition electrode 10. Further, as in another modified example shown in FIG. 10, both sides of the tip of the ignition electrode 10 may be obliquely deleted to form the ignition energy concentration portion 11.

Next, in the sixth embodiment shown in FIG. 11, two points at the distal end of the peripheral surface of the ignition electrode 10 are deleted so that the cross section of the ignition electrode 10 has a substantially sector shape.
At one location in the radial direction of the ignition electrode 10, the ignition electrode 1
An ignition energy concentrating portion 11 in the axial direction of 0 is formed.

In the ignition electrodes 10 of the fourth to sixth embodiments, the same combustion apparatus 1 as in the first embodiment is used.
By applying the method described above, a spark can be reliably generated between the ignition energy concentration portion 11 and the inner peripheral edge of the first ejection hole 4. Here, in each of these embodiments, since the ignition energy concentration portion 11 is formed by partially removing the tip of the ignition electrode 10, the area of the cross section at the tip of the ignition electrode 10 is set. Is smaller than the cross-sectional area of the original round bar-shaped portion. Therefore, by increasing the size of the entire ignition electrode 10, the distance C between the inner peripheral edge of the first ejection hole 4 and each of the ignition energy concentration portions 11 can be reduced, and a spark can be generated more reliably.

Next, an application example in which the ignition device according to the present invention is applied to a combustion device of a type different from that of the combustion device 1 shown in FIG. 1 will be described with reference to FIGS. First, a second application example shown in FIG. 12 has a configuration in which the ignition electrode 10 of the first embodiment is arranged outside the combustion device 1 and a spark is generated between the ignition electrode 10 and the combustion device 1. is there. Combustion device 1 in this second application example
Is a premixed gas burner in which the tip of a cylindrical burner main body 2 is closed, and a plurality of premixed gas ejection holes 16 are formed on the outer periphery of the tip of the burner main body 2. The ignition electrode 10 is provided so as to face one of the premixed gas ejection holes 16. Therefore, the ignition electrode 10
In order to generate a spark with the inner peripheral edge of the premixed gas ejection hole 16, the premixed gas from the premixed gas ejection hole 16 is ignited. Then, the premixed gas from one premixed gas ejection hole 16 is ignited, and when combustion is started, the premixed air from the remaining premixed gas ejection hole 16 is also ignited.

Next, the combustion apparatus 1 in the third application example shown in FIG. 13 is a surface combustion burner, and includes a flame holding body 18 having a large number of small-diameter premixed gas injection holes 17, 17,. ing. The flame stabilizing body 18 is usually made of ceramic, and is configured to generate a spark between the metal holding frame 19 for holding the flame stabilizing body 18 and the ignition electrode 10. The ignition electrode 10 applied to the combustion device 1 is arranged such that at least one ignition energy concentration portion 11 faces the holding frame 19. In the third application example, the ignition electrode 10 of the first embodiment is used, and in this case, the ignition electrode 1 is used.
0 is arranged in a direction perpendicular to the inner peripheral edge of the flame holding body 18, and one of the ignition energy concentrating parts 11 is close to the inner peripheral edge of the holding frame 19. So that Here, when the flame stabilizer 18 is made of a conductive material, a spark is generated between the flame stabilizer 18 and the ignition electrode 10 instead of the holding frame 19. It can be configured as follows.

Next, an application example in which a spark is generated between two ignition electrodes 10 and 10 to ignite a combustion device will be described with reference to FIG. Here, in FIG. 14, only the ignition electrode is shown and the illustration of the combustion device is omitted, but the fourth application example shown in FIG. 14 is an application example in the case of using the ignition device of a liquid fuel burner. .

Now, in the fourth application example, the two ignition electrodes 10 of the first embodiment are arranged in parallel, and one ignition energy concentration part 11 in each of the ignition electrodes 10 is close to each other. Has been placed. In the fourth application example, each of the ignition electrodes 10 is arranged at a position crossing the fuel ejected from the combustion device so as to generate a spark. Therefore, the fuel from the combustion device is supplied in a state where a spark is generated between the ignition electrodes 10, and is ignited by the energy of the spark.

Here, the arrangement of the ignition electrodes 10 in the fourth application example can be used similarly when the ignition electrodes 10 of the first to sixth embodiments are used. Here, in the case where a plurality of ignition energy concentration portions 11 are provided in each of the ignition electrodes 10, that is, in the case of the ignition electrodes 10 in the first embodiment to the fifth embodiment, one of the ignition electrodes 10 is used. Two ignition energy concentrators 1
When 1 is worn out, the direction of each of the ignition electrodes 10 is changed, and the other ignition energy concentration portions 11 face each other, so that a spark can be reliably generated using the new ignition energy concentration portion 11, and therefore, Each ignition electrode 10
Can be used for a long period of time.

In the above description, the ignition energy concentrating portion 11 is formed so as to be linear in the axial direction of the ignition electrode 10, but if it is formed in the radial direction of the ignition electrode 10, for example, As shown in FIG. 15, each of the ignition energy concentration portions 11 is formed in the radial direction by bending the flat portion 12 of the ignition electrode 10 of the first embodiment. The ignition electrode 10 of the seventh embodiment shown in FIG. 15 is used, for example, in the combustion device 1 shown in FIG. In this case, the arrangement of the ignition electrode 10 with respect to the combustion device 1 is arranged such that the axial direction of the burner main body 2 and the axial direction of the ignition electrode 10 are parallel to each other, as in a fifth application example shown in FIG. And the ignition energy concentrating unit 1
1 is arranged so as to face one premixed gas ejection hole 16.

[0040]

According to the present invention, a spark can be reliably generated, and a spark can be reliably generated for a long period of time by forming the ignition energy concentration portion in a linear shape. .

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view showing a first embodiment of an ignition device according to the present invention.

FIG. 2 is an explanatory front enlarged view of FIG. 1;

FIG. 3 is a perspective explanatory view showing a second embodiment of the ignition device according to the present invention.

FIG. 4 is a perspective explanatory view showing a modification of the second embodiment.

FIG. 5 is an explanatory perspective view showing another modified example of the second embodiment.

FIG. 6 is an explanatory perspective view showing a third embodiment of the ignition device according to the present invention.

FIG. 7 is an explanatory perspective view showing a fourth embodiment of the ignition device according to the present invention.

FIG. 8 is a perspective explanatory view showing a fifth embodiment of the ignition device according to the present invention.

FIG. 9 is an explanatory perspective view showing a modification of the fifth embodiment.

FIG. 10 is an explanatory perspective view showing another modification of the fifth embodiment.

FIG. 11 is an explanatory perspective view showing a sixth embodiment of the ignition device according to the present invention.

FIG. 12 is an explanatory side view showing a second application example of the ignition device according to the present invention.

FIG. 13 is an explanatory perspective view showing a third application example of the ignition device according to the present invention.

FIG. 14 is an explanatory plan view showing a fourth application example of the ignition device according to the present invention.

FIG. 15 is a perspective explanatory view showing a seventh embodiment of the ignition device according to the present invention.

FIG. 16 is an explanatory side view showing a fifth application example of the ignition device according to the present invention.

FIG. 17 is an explanatory longitudinal side view showing an example of a conventional ignition device.

FIG. 18 is an explanatory front view of FIG. 17;

[Explanation of symbols]

 10 ignition electrode 11 ignition energy concentration part

Claims (2)

[Claims] An ignition device comprising an ignition electrode and an ignition energy concentration portion formed at a front end of the ignition electrode. 2. The ignition device according to claim 1, wherein the ignition energy concentration section is formed in a linear shape.