JPH08200675A - Ignition device - Google Patents

Abstract

PURPOSE: To provide an ignition device which can be assembled at a low cost and in which a connection with a fixing plate for an earth electrode can be performed surely. CONSTITUTION: In an ignition device 20 in which a plurality of electrodes including an ignition electrode 22 and an earth electrode 23 are arranged at an insulator 21 and the earth electrode is electrically connected to a part of a combustion device, the earth electrode 23 has an extension part 23a passing and extending through the insulator 21 and this extending part is spot welded to a fixing plate 25.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ignition device suitable for being mounted on, for example, a bathtub equipped with a burner or a water heater.

[0002]

2. Description of the Related Art Conventionally, such an ignition device is constructed as shown in FIGS. 3 and 4, for example. 3 and 4
In the above, the ignition device 10 is composed of an insulator 11 and a plurality of electrodes 12, 13, 14 arranged on the insulator 11.

The insulator 11 is, for example, a molded product of insulating ceramics, has a substantially rectangular parallelepiped shape, and has a back surface (upper side in FIG. 3) so that its cross section has a gate shape.
Is provided with a concave portion 11a formed in the central portion thereof. As a result, two convex portions 11b and 11c that are adjacent to each other with the concave portion 11a interposed therebetween are defined on both sides of the concave portion 11a. On the front side of the insulator 11, that is, on the side opposite to the concave portions 11a and the convex portions 11b and 11c, a plurality of electrodes 1 to be described later are provided.
The projecting portion 15 covers the base portions of 2, 13, 14
However, it is projected integrally with the insulator 11.

In the illustrated case, the plurality of electrodes are composed of three ignition electrodes 12, ground electrodes 13, and frame rods 14 which are formed of a thin metal rod material having excellent heat resistance such as an alloy of nickel and iron. Has been done.

The ignition electrode 12 is designed to blow a spark toward a low potential side (target side) when a predetermined voltage is applied, and is inserted into a through hole formed in the insulator 11. The insulator 11 penetrates from the convex portion 11c side, 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 kept at a predetermined distance.

The ground electrode 13 is a recessed portion 11a of the insulator 11.
The insulator 11 is inserted through a through hole formed from the side, penetrates the insulator 11, and the tip side extends toward a burner described later. As shown in FIGS. 5 and 6, the rear end side of the ground electrode 13 is attached to the casing 3 serving as the ground, and the mounting bracket 1
By abutting through 6 to make electrical contact with this mounting member 16, a lower potential than the ignition electrode 12 can be maintained. As a result, sparks due to the discharge of the ignition electrode 12 can be introduced.

As shown in FIG. 3, the frame rod 14 is inserted into a through hole extending from the convex portion 11b of the insulator 11 to the front side, and extends long toward the burner on the front side of the insulator 11, and from this burner. The flame is constructed so that it covers the surface sufficiently. By constantly applying a predetermined voltage, the flame rod 14 is exposed to flame and generates a predetermined signal, so that the combustion state of the burner can be detected.

According to the ignition device 10 thus constructed, 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 pot or the like, and a casing 3 that surrounds the burner 2. As shown in FIG. 5, the casing 3 has a mounting hole 3a formed on the side wall thereof slightly above the burner 2. This mounting hole 3a is used for the insulator 1
Corresponding to the first projecting portion 15, the projecting portion 15 is closely fitted. Therefore, as shown in FIGS. 5 and 6, each electrode 12, 13, 14 can be formed by simply fitting the protrusion 15 on the back side (left side in FIG. 5) of the insulator 11 into the mounting hole 3a of the casing 3. , Near the flame opening of the burner 2 and extends substantially horizontally above the burner 2.

Next, as shown in FIG. 5, a mounting member 16 having a substantially U-shaped cross section is fitted into the recess 11a of the insulator 11. The rising position of the U-shaped portion 16a of the mounting bracket 16 substantially coincides with the height of the recess 11a of the insulator 11. Moreover, the width of the mounting bracket 16 is as shown in FIG.
It is formed so as to be at least smaller than the width of the recess 11a of the insulator 11. Therefore, by simply fitting the U-shaped portion 16a of the mounting member 16 into the recess 11a of the insulator 11 and screwing the mounting portion 16b of the mounting member 16 to the side wall of the casing 3, the ignition device 10 can be installed in the gas chamber. Can be incorporated into.

Here, as shown in FIG. 6, the ignition electrode 12
Is bent above the burner 2 toward the ground electrode 13 side adjacent to the ignition electrode 12. Therefore, when a predetermined voltage is applied to the ignition electrode 12, the spark is discharged and the sparks fly toward the ground electrode 13 on the low potential side. As a result, the burner 2 is ignited.

[0011]

However, in the ignition device 10 having such a structure, the ground electrode 13 is used.
When the insulator 11 is inserted into the insulator 11, the rear end portion of the ground electrode 13 protruding from the back side of the insulator 11 becomes
It contacts the surface of the mounting plate 16 fixed to. As a result, the ground electrode 13 is electrically connected to the mounting plate 16. Therefore, the insulator 11 must be in contact with the earth electrode 13 and the insulator 11 must be fixed, and the earth electrode 13 and the casing 3 are connected by the contact. It was

In order to fix and hold the mounting plate 16 to the insulator 11, the mounting plate 1 is held while holding the insulator 11.
Since it is necessary to fix 6 to the casing 3 with the screw 17, there is a problem that skill is required in the screwing process in the main line, screwing takes time, and cost increases. Further, since the frame rod 14 is connected to the substrates by tab terminals or the like, the portion protruding through the insulator 11 is pressed to form a round bow into a plate shape. However, since the material used for this electrode has heat resistance, it is very hard and difficult to process.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an ignition device which is assembled at a low cost and in which the ground electrode is securely connected to a mounting plate. There is.

[0014]

SUMMARY OF THE INVENTION According to the invention, the object is to provide a single insulator fixed to a mounting plate to be arranged adjacent to the burner inside a casing enclosing the burner. In the ignition device, a plurality of electrodes including an ignition electrode and an earth electrode are arranged so as to extend from the insulator toward the burner, and the earth electrode is electrically connected to the mounting plate. It is achieved by an ignition device, characterized in that it has an extension projecting through the insulator, which extension is spot-welded to the mounting plate.

[0015]

According to the above 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, the tip portion of the ignition electrode is discharged, and the sparks fly toward the ground electrode on the low potential side. As a result, the combustion device such as the burner of the bath can is ignited.

Here, the rear end of the ground electrode is projected through the insulator, and this protrusion is spot-welded to the mounting plate fixed to the insulator. The mounting plate and the mounting plate are electrically connected to each other and mechanically fixed.

Therefore, the electrical connection between the ground electrode and the mounting plate is surely made.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below in detail with reference to the accompanying drawings. The examples described below are
Since it is a preferred specific example of the present invention, various technically preferable limitations are attached, but the scope of the present invention is, unless otherwise stated to limit the present invention, in the following description.
It is not limited to these modes.

1 and 2 show an embodiment of an ignition device according to the present invention. In FIG. 1, the ignition device 20
Is an insulator 21 and a plurality of electrodes 2 arranged on the insulator 21.
2, 23, 24 and the mounting plate 2 mounted on the insulator 21
And 5.

The insulator 21 is, for example, a molded product of insulating ceramics, and has a recess 21a formed in the central portion of the back surface (upper side in FIG. 1) so that its cross section has a gate shape. As a result, the recesses 2 are formed on both sides of the recess 21a.
Two protrusions 21b and 21c adjacent to each other with 1a in between are formed. Further, a plurality of electrodes 22, 23, 24 described later are provided on the front side of the insulator 21, that is, on the opposite side of the concave portions 21a and the convex portions 21b and 21c, and the root portions of these electrodes 22, 23, 24 are provided. The projecting portion 26 projects integrally with the insulator 21 so as to cover the insulator 21.

In the illustrated case, the plurality of electrodes are configured as three ignition electrodes 22, a ground electrode 23, and a frame rod 24 which are formed of a thin metal rod material having excellent heat resistance such as an alloy of nickel and iron. Has been done.

Here, the ignition electrode 22 is designed to blow a spark to the ground electrode 23 on the low potential side by applying a predetermined voltage, and is inserted into a through hole formed in the insulator 21. Then, the insulator 21 penetrates from the convex portion 21c side, extends downward in FIG. 1 toward a burner described later, and is further bent toward the ground electrode 23 side. As a result, the tip of the ignition electrode 22 and the tip of the ground electrode 23 can be kept at a predetermined distance.

The ground electrode 23 is a recess 21a of the insulator 21.
It is inserted into the through hole from the side and penetrates the insulator 21,
The tip side extends toward a burner described later. The rear end side of the ground electrode 23 largely projects from the insulator 21.

The frame rod 24 is formed in the recess 2 of the insulator 21.
The insulator 21 is inserted into the through hole from the side of 1a to the front side.
Is extended to the burner on the front side of the burner, and the flame from this burner is configured to sufficiently cover the surface thereof. By constantly applying a predetermined voltage, the flame rod 24 is exposed to flame and generates a predetermined signal, so that the combustion state of the burner can be detected.

The mounting plate 25 is formed of a metal plate such as a steel plate or stainless steel, and is a recess 21 a of the insulator 21.
The engaging portion 25a that abuts the surface of the insulator 21 inside, and the extending portions 25b and 25b that project from the engaging portion 25a to both sides.
have. The extension portions 25b, 25b are provided with screw holes 25e, 25e for fixing with screws to a casing (not shown) serving as a ground, respectively. Further, the mounting plate 25 is provided with the engaging portion 25a to the insulator 21.
A rising portion 25d extending along the rear end of the ground electrode 23 is provided perpendicular to the surface of the ground electrode 23.

Here, the rear end portion 23 of the earth electrode 23
The a is joined to the rising portion 25d of the mounting plate 25 by spot welding. As a result, the mounting plate 25
While being electrically connected to the ground electrode 23,
It will be mechanically fixed and held.

Further, the frame rod 24 has a terminal 27.
Are joined by spot welding. The terminal 27 has a tab terminal shape, and wiring can be easily performed between the boards by attaching wiring to the receptacle terminal corresponding to the terminal shape.

The ignition device 20 according to the present embodiment is constructed as described above, and the mounting plate 25 is spot-welded to the ground electrode 23 so that it is substantially fixed to the insulator 21. Therefore, when assembling to the combustion device, 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,
The mounting plate 25 is screwed to the casing surrounding the burner. In this way, the ignition device 20 is attached to the combustion device at a predetermined position.
As a result, each of the electrodes 22, 23, 24 extends substantially horizontally in the vicinity of the flame openings of the burners and above the flame openings of the burners. Thus, the ignition device 20 is incorporated in a combustion device such as a gas kettle.

When a predetermined voltage is applied to the ignition electrode 22, the tip of the ignition electrode 22 is discharged, and the sparks fly toward the ground electrode 23 on the low potential side. This allows
The burner burner of the combustion device is ignited.

Here, the ground electrode 23 has a rear end portion 2
Since 3a is connected to the rising portion 25d of the mounting plate 25 by spot welding, the ground electrode 23 is
It is grounded to the casing of the combustion device via the mounting plate 25. Moreover, since spot welding is performed in the sub line, the manufacturing cost is reduced.

In this case, the rear end portion 23a of the earth electrode 23
However, since it is spot-welded to the rising portion 25d of the mounting plate 25, the ground electrode 23 is surely grounded without any contact failure with the mounting plate 25. Further, even when the ignition device 20 is assembled, the mounting work can be easily performed because the mounting plate 25 can be screwed to the casing without holding the insulator 21.

In the above description, the ignition device 20
It is obvious that the insulator 21 constituting the above is not limited to the illustrated shape and may have another shape such as a disc shape. It is also apparent that each of the electrodes 22, 23, 24 is not limited to the shape shown in the figure, and may have another shape depending on how it is attached to the casing.

Further, the ignition device 20 of the present embodiment is not only used for igniting a gun type burner which is often used in petroleum equipment, but also a water heater, bath heater, heater using gas, petroleum or the like. It can also be used in a combustion device that requires ignition, such as.

[0034]

As described above, according to the present invention, it is possible to provide an extremely excellent ignition device which can be assembled at a low cost and in which the ground electrode can be reliably connected to the mounting plate. it can.

[Brief description of drawings]

FIG. 1 is a schematic front view showing an embodiment of an ignition device according to the present invention.

2 is a side view of the ignition device of FIG. 1. FIG.

FIG. 3 is a schematic front view showing an embodiment of the ignition device according to the present invention.

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.

FIG. 6 is a plan view showing an assembled state of the ignition device of FIG.

FIG. 7 is a front view showing an assembled state of the ignition device of FIG.

[Explanation of symbols]

 20 Ignition device 21 Insulator 22 Ignition electrode 23 Earth electrode 23a Rear end 24 Frame rod 24a Rear end 25 Mounting plate 25a Engagement part 25b Extension 25d Rise 26 Protrusion 27 Terminal

Claims (1)

[Claims] 1. An igniter in which a plurality of electrodes including an ignition electrode and an earth electrode are arranged on an insulator, and the earth electrode is electrically connected to a part of a combustion device, wherein the earth electrode is the insulator. An ignition device, comprising: an extension portion penetrating through and projecting, the extension portion being spot-welded to a mounting plate.