JP3597587B2 - Ignition device - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to an ignition device suitable for being mounted on, for example, a bath kettle or a water heater provided with a burner.
[0002]
[Prior art]
Conventionally, such an ignition device is configured as shown in FIGS. 3 and 4, for example.
3 and 4, the ignition device 10 includes an insulator 11 and a plurality of electrodes 12, 13, and 14 disposed on the insulator 11.
[0003]
The insulator 11 is a molded product of, for example, insulating ceramics, has a substantially rectangular parallelepiped shape, and has a concave portion formed in a central portion of the back surface (upper side in FIG. 3) so that its cross section has a gate shape. 11a. As a result, on both sides of the concave portion 11a, two convex portions 11b and 11c adjacent to each other across the concave portion 11a are defined.
Further, on the front side of the insulator 11, that is, on the side opposite to the concave portions 11a, the convex portions 11b and 11c, a protruding portion 15 is integrated with the insulator 11 so as to cover the root portions of a plurality of electrodes 12, 13 and 14 described later. Overhangs.
[0004]
In the case of the drawing, the plurality of electrodes are composed of three ignition electrodes 12, a ground electrode 13, and a frame rod 14 formed of a thin metal bar having excellent heat resistance such as an alloy of nickel and iron. .
[0005]
Here, when a predetermined voltage is applied, the ignition electrode 12 emits a spark toward the low potential side (target side). The ignition electrode 12 is inserted into a through hole formed in the insulator 11, and And extends toward the burner described later, and is further bent toward the ground electrode 13 side. As a result, the tip of the ignition electrode 12 and the tip of the ground electrode 13 can be maintained at a predetermined interval.
[0006]
The ground electrode 13 is inserted through a through hole formed from the concave portion 11a side of the insulator 11 and penetrates the insulator 11, and the tip end extends toward a burner described later.
5 and 6, the rear end of the ground electrode 13 is brought into contact with the casing 3 serving as the ground via the mounting bracket 16, thereby electrically contacting the mounting bracket 16. The potential lower than the ignition electrode 12 can be maintained. As a result, a spark caused by the discharge of the ignition electrode 12 can be guided.
[0007]
As shown in FIG. 3, the frame rod 14 is inserted into a through hole extending from the protrusion 11b of the insulator 11 to the front side, and extends long toward the burner on the front side of the insulator 11, and the flame from the burner causes the flame from the burner. It is designed to cover the surface sufficiently. The frame rod 14 is always applied with a predetermined voltage, is exposed to a flame, generates a predetermined signal, and can detect the combustion state of the burner.
[0008]
According to the ignition device 10 configured as described above, the ignition device 10 is assembled to the combustion device as shown in FIGS. The combustion device includes a burner 2 housed in a gas kettle or the like, and a casing 3 surrounding the burner 2.
As shown in FIG. 5, the casing 3 is provided with a mounting hole 3a slightly above the burner 2 on the side wall thereof. The mounting hole 3 a has a shape corresponding to the protrusion 15 of the insulator 11 so that the protrusion 15 is closely fitted. Therefore, only by fitting the protruding portion 15 on the back side (the left side in FIG. 5) of the insulator 11 into the mounting hole 3a of the casing 3, as shown in FIGS. , And extends substantially horizontally above the burner 2 in close proximity to the burner opening of the burner 2.
[0009]
Next, as shown in FIG. 5, a mounting bracket 16 having a substantially U-shaped cross section is fitted into the recess 11 a of the insulator 11. The rising position of the U-shaped portion 16 a of the mounting bracket 16 substantially matches the height of the concave portion 11 a of the insulator 11. Moreover, the width of the mounting bracket 16 is formed to be at least smaller than the width of the concave portion 11a of the insulator 11, as shown in FIG. For this reason, the ignition device 10 can be mounted in the gas cooker only by fitting the U-shaped portion 16a of the mounting bracket 16 into the concave portion 11a of the insulator 11 and screwing the mounting portion 16b of the mounting bracket 16 to the side wall of the casing 3. Can be incorporated into
[0010]
Here, as shown in FIG. 6, the tip of the ignition electrode 12 is bent above the burner 2 toward the earth electrode 13 adjacent to the ignition electrode 12. Therefore, when a predetermined voltage is applied to the ignition electrode 12, the spark is discharged and the spark flies toward the ground electrode 13 on the low potential side. Thereby, the burner 2 is ignited.
[0011]
[Problems to be solved by the invention]
However, in the ignition device 10 having such a configuration, the earth electrode 13 is fixed to the insulator 11 by inserting the earth electrode 13 into the insulator 11 so that the rear end of the earth electrode 13 protruding from the back side of the insulator 11. It comes into contact with the surface of the mounting plate 16. Thus, the ground electrode 13 is electrically connected to the mounting plate 16.
Therefore, the insulator 11 must be fixed while being in contact with the ground electrode 13, and further, since the ground electrode 13 and the casing 3 are connected by the contact, there is a problem that electrical connection failure is likely to occur. Was.
[0012]
Further, in order to fix and hold the mounting plate 16 to the insulator 11, it is necessary to fix the mounting plate 16 to the casing 3 with the screw 17 while holding the insulator 11, so that the main line is screwed. There is a problem that skill is required in the process, time is required for screwing, and the cost is increased.
Further, since the frame rod 14 is connected to the substrates with tab terminals or the like, a portion protruding through the insulator 11 is pressurized and processed into a plate shape from a round bow. However, since the material used for this electrode has heat resistance, it was very hard and difficult to process.
[0013]
SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to provide an ignition device that can be assembled at a low cost and that a ground electrode is securely connected to a mounting plate.
[0014]
[Means for Solving the Problems]
According to the present invention, the object is to provide, according to the present invention, a single insulator fixed to a mounting plate to be disposed adjacent to a burner inside a casing surrounding the burner so as to extend from the insulator toward the burner. An ignition device in which a plurality of electrodes including an ignition electrode and a ground electrode are provided, and the ground electrode is electrically connected to the mounting plate, wherein the ground electrode protrudes through the insulator. And wherein the extension is spot-welded to the mounting plate.
[0015]
[Action]
According to the invention, since the ground electrode is electrically connected to the mounting plate by spot welding, the ground electrode is grounded via the mounting plate. Therefore, when a predetermined voltage is applied to the ignition electrode, discharge occurs from the tip of the ignition electrode, and the spark flies toward the low potential side earth electrode. Thereby, a combustion device such as a burner of the bath kettle is ignited.
[0016]
Here, the rear end of the ground electrode projects through the insulator, and this projection is spot-welded to the mounting plate fixed to the insulator. Are electrically connected to each other and are mechanically fixed.
[0017]
Therefore, the electrical connection between the ground electrode and the mounting plate is reliably performed.
[0018]
【Example】
Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.
In addition, since the Examples described below are preferred specific examples of the present invention, various technically preferable limitations are added, but the scope of the present invention particularly limits the present invention in the following description. The embodiments are not limited to these embodiments unless otherwise described.
[0019]
1 and 2 show an embodiment of the ignition device according to the present invention.
In FIG. 1, the ignition device 20 includes an insulator 21, a plurality of electrodes 22, 23, 24 disposed on the insulator 21, and a mounting plate 25 mounted on the insulator 21.
[0020]
The insulator 21 is a molded product of, for example, insulating ceramics, and has a concave portion 21a formed in a central portion on the back surface (upper side in FIG. 1) so that the cross section thereof has a gate shape. As a result, two convex portions 21b and 21c adjacent to each other with the concave portion 21a interposed therebetween are formed on both sides of the concave portion 21a.
A plurality of electrodes 22, 23, and 24, which will be described later, are provided on the front side of the insulator 21, that is, on the side opposite to the concave portions 21a and the convex portions 21b and 21c. Is projected integrally with the insulator 21 so as to cover the insulator 21.
[0021]
In the case of the drawing, the plurality of electrodes are configured as three ignition electrodes 22, a ground electrode 23, and a frame rod 24 formed of a thin metal bar having excellent heat resistance such as an alloy of nickel and iron. .
[0022]
Here, when a predetermined voltage is applied, the ignition electrode 22 emits a spark to the earth electrode 23 on the low potential side, and is inserted into a through hole formed in the insulator 21 to be insulated. 1 extends downward from FIG. 1 toward a burner, which will be described later, and is bent further toward the ground electrode 23. As a result, the tip of the ignition electrode 22 and the tip of the ground electrode 23 can be maintained at a predetermined distance.
[0023]
The ground electrode 23 is inserted into the through-hole from the concave portion 21a side of the insulator 21 and penetrates the insulator 21. The tip side extends toward a burner described later. The rear end of the ground electrode 23 protrudes greatly from the insulator 21.
[0024]
The frame rod 24 is inserted into a through hole extending from the side of the concave portion 21a of the insulator 21 to the front side, and extends long toward the burner on the front side of the insulator 21. The flame from the burner is sufficiently applied to the surface. It is configured. The frame rod 24 is always applied with a predetermined voltage, is exposed to a flame, generates a predetermined signal, and can detect the combustion state of the burner.
[0025]
The mounting plate 25 is formed of, for example, a metal plate such as a steel plate or a stainless steel, and has an engaging portion 25a in contact with the surface of the insulator 21 in the concave portion 21a of the insulator 21 and protrudes to both sides from the engaging portion 25a. It has extensions 25b, 25b.
The extension portions 25b, 25b are provided with screw holes 25e, 25e, respectively, for fixing the casings (not shown) to be grounded by screws. Further, the mounting plate 25 has a rising portion 25d extending from the engaging portion 25a perpendicular to the surface of the insulator 21 along the rear end of the ground electrode 23.
[0026]
Here, the rear end 23a of the ground electrode 23 is joined to the rising portion 25d of the mounting plate 25 by spot welding. Thus, the mounting plate 25 is electrically connected to the ground electrode 23 and is mechanically fixed and held.
[0027]
Further, the frame rod 24 has the terminals 27 joined by spot welding.
The terminal 27 has the shape of a tab terminal, and wiring between the substrates is easily performed by attaching wiring to the receptacle terminal corresponding to the terminal shape.
[0028]
The ignition device 20 according to the present embodiment is configured as described above, and is substantially fixed to the insulator 21 by spot welding the mounting plate 25 to the ground electrode 23. For this reason, when assembling to the combustion device, the casing surrounding the periphery of the burner is slightly above the burner of the combustion device by the screw holes 25e, 25e of the extension portions 25b, 25b of the mounting plate 25. Then, the mounting plate 25 is screwed.
As described above, the ignition device 20 is mounted at a predetermined position with respect to the combustion device. As a result, each of the electrodes 22, 23, and 24 approaches the burner of the burner and extends substantially horizontally above the burner of the burner. Thus, the ignition device 20 is incorporated in a combustion device such as a gas kettle.
[0029]
Further, when a predetermined voltage is applied to the ignition electrode 22, a discharge is caused from the tip of the ignition electrode 22, and the spark flies toward the ground electrode 23 on the low potential side. Thus, the burner of the combustion device is ignited.
[0030]
Here, since the rear end 23a of the ground electrode 23 is connected to the rising portion 25d of the mounting plate 25 by spot welding, the ground electrode 23 is connected to the casing of the combustion device via the mounting plate 25. To be grounded. In addition, since the spot welding is performed on the sub-line, the manufacturing cost is reduced.
[0031]
In this case, since the rear end portion 23a of the ground electrode 23 is spot-welded to the rising portion 25d of the mounting plate 25, contact failure of the ground electrode 23 to the mounting plate 25 does not occur, so Is connected to ground.
Also, at the time of assembling the ignition device 20, since the screw can be screwed while holding only the mounting plate 25 with respect to the casing without holding the insulator 21, the assembling work is easily performed.
[0032]
In the above description, it is apparent that the shape of the insulator 21 constituting the ignition device 20 is not limited to the illustrated shape, but may be another shape such as a disk shape. It is also apparent that the electrodes 22, 23, and 24 are not limited to the shapes shown in the drawing, but may have other shapes according to the state of attachment to the casing.
[0033]
Further, the ignition device 20 of the present embodiment is used not only for igniting a gun-type burner often used for petroleum equipment and the like, but also for a water heater, a bath pot, a heater and the like using gas, oil and the like. It can also be used for combustion devices that require ignition.
[0034]
【The invention's effect】
As described above, according to the present invention, it is possible to provide an extremely excellent ignition device that can be assembled at low cost and that the connection of the ground electrode to the mounting plate is reliably performed.
[Brief description of the drawings]
FIG. 1 is a schematic front view showing an embodiment of an ignition device according to the present invention.
FIG. 2 is a side view of the ignition device of FIG. 1;
FIG. 3 is a schematic front view showing an embodiment of the ignition device according to the present invention.
FIG. 4 is a side view of the ignition device of FIG. 1;
FIG. 5 is a side view showing an assembled state of the ignition device of FIG. 1;
FIG. 6 is a plan view showing an assembled state of the ignition device of FIG. 1;
FIG. 7 is a front view showing an assembled state of the ignition device of FIG. 1;
[Explanation of symbols]
Reference Signs List 20 ignition device 21 insulator 22 ignition electrode 23 earth electrode 23a rear end 24 frame rod 24a rear end 25 mounting plate 25a engaging portion 25b extension 25d rising portion 26 projecting portion 27 terminal

Claims (1)

In an igniter in which a plurality of electrodes including an ignition electrode and a ground electrode are disposed on the insulator, and the ground electrode is electrically connected to a part of the combustion device,
An ignition device wherein an earth electrode has an extension projecting through the insulator, and the extension is spot-welded to a mounting plate.

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