JPS6136927Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an incomplete combustion detection element comprising an element body made of zirconia or other material and electrodes on both the front and back surfaces of the element body.

As this type of element, a slit is formed in the element body at its tip side, and electrodes on both sides are arranged in parallel in at least two sets on one side and the other side of the slit, and two elements are used in one element. A device that achieves similar operation is Japanese Patent Application No. 54-157813 (Japanese Unexamined Patent Publication No. 56-1989).
79951).

However, in this case, the slit is provided up to the root side of the element body to electrically insulate each element formed on both sides of the slit, which inconveniently weakens the element itself.

The purpose of the present invention is to provide an element that eliminates such inconveniences, and the present invention aims to provide an element that eliminates such inconveniences. In a type in which at least one slit 3 is formed on the tip side and the electrodes 2, 2 on both sides are arranged in parallel in at least two sets on one side and the other side of the slit 3, two adjacent sets of electrodes 2, 2 are disposed close to each other on both side edges of the slit 3 on the distal end side of the element body 1, and adjacent electrodes 2, 2 are provided with a gap between them in the portion extending toward the tail end of the element body 1. It consists of expanding.

The element body 1 is composed of a plate-shaped sintered body made of, for example, zirconia or other oxygen ion conductive solid electrolyte, and has a slit 3 formed on the tip side as shown in FIG. 3 or 4. , electrodes 2 on both the front and back sides extending in a band shape from the tip side to the tail side of the element body 1 on one side and the other side of the slit 3;
2 are arranged in parallel, and the first lead wire 4a is connected from the tail end of the element body 1 to the back electrode 2 of one set.
and a second lead wire 4b commonly connected to the front electrode 2 of one set and the back electrode 2 of the other set,
A third lead wire 4c connected to the other set of surface electrodes 2 is led out and adjacent to the third lead wire 4c.

The two sets of electrodes 2, 2 are arranged close to each other on both side edges of the slit 3 on the tip side of the element body 1, and the gap between the two sets of electrodes 2, 2 is narrowed as much as possible.

In the case shown in the third figure, each electrode 2 is connected to the element body 1.
It extends straight from the distal end to the caudal end, but if the part extending toward the caudal end is bent outward as shown in Figure 4, the gap between the two sets of electrodes 2, 2 is widened in this part, as will be described later. There are advantages to doing so.

Next, to explain its operation, the element body 1
has an extremely high internal resistance and exhibits insulating properties until it is heated to a predetermined operating temperature, but when heated to the operating temperature, the internal resistance decreases and the electrodes 2 and
It functions as a so-called oxygen concentration battery element that generates an electromotive force according to the difference in oxygen concentration between the two, and when this is placed opposite to the front of the burner 5 on the tip side as shown in FIGS. 5 and 6, the burner Short circuits are prevented by the insulating properties of the tail ends of the slits 5 which are not heated, and both sides of the slits 3 function as one oxygen concentration battery element each having front and back electrodes 2, 2, respectively.

Therefore, when the electrodes 2 on one side of each set facing the burner 5 are exposed to the combustion exhaust gas flowing as shown by the dotted lines from the state shown by the solid line in FIG. Electrodes 2, 2 on both sides
An electromotive force is generated according to the difference in oxygen concentration between the electrodes 2 and 2, and this is taken out as an output between each set of electrodes 2, 2.

In this case, the gap between the two sets of electrodes 2, 2 is wide,
Even if combustion exhaust comes into contact with one set of electrodes 2, the combustion exhaust may not come into contact with the other set of electrodes 2 and no output is generated from the other set. , 2 are arranged close to each other, such inconvenience can be prevented as much as possible.

The tail end side of the element main body 1 may be heated by the fluctuation of the combustion flame, etc., and the internal resistance may be reduced. This ensured electrical insulation between the electrodes 2, 2.

In the drawing, reference numeral 6 indicates a comparator that operates a safety device 7 such as a safety valve interposed in a gas pipe when the output from the element changes to a set value. 6 to the first and second lead wires 4
a, 4b to input the output generated between the electrodes 2, 2 of one set, and the other set of electrodes 2, 2 via the first and third lead wires 4a, 4c.
It is possible to freely switch between inputting the total output generated during this period.

In the above embodiment, the element was prepared as an output type during incomplete combustion, which generates output due to incomplete combustion of the burner 5, but each set of electrodes 2, located on the side opposite to the burner 5 An pilot burner is provided to heat the burner 5 to a constant oxygen-deficient state, and burner 5 is heated during normal combustion.
A normal combustion output type that generates an output depending on the oxygen concentration between the side electrode 2 and the pilot burner side electrode may be provided, and in this case as well, if each set of electrodes 2, 2 is placed close to each other, It is advantageous to make the combustion flame of the pilot burner relatively small so that both electrodes 2, 2 can be brought into even contact with the flame.

Further, in the above embodiment, an oxygen concentration battery type material such as zirconia was used as the element body 1, but the present invention is not limited to this. A variable resistance element body made of titania or other materials shown may also be used.

In addition, in the illustrated example, when each set of electrodes 2, 2 is formed close to both side edges of the slit 3, the electrode 2 does not protrude into the slit 3 and short circuit between the electrodes 2, 2 occurs. Although a slight gap was provided between the side edge of the slit 3 and the electrode 2, a center electrode was previously formed on the tip side of the element body 1, and the slit 3 separated the electrode. This gap can be eliminated by doing this.

As described above, according to the present invention, two sets of adjacent electrodes 2, 2 are arranged close to both side edges of the slit 3 on the tip side of the element body 1, and the two sets of electrodes 2,
The gap between the electrodes 2 is narrowed as much as possible, so that the combustion state of the burner can be detected under the same conditions. Because the gap has been widened, compared to the previous application in which the slits are provided all the way to the root side to provide electrical insulation between the elements separated by the slits, only the slits need to be provided on the tip side. This has the advantage that a more robust incomplete combustion detection element can be obtained compared to conventional methods.

[Brief explanation of the drawing]

FIG. 1 is a front view of one embodiment of the present invention, and FIGS. 2 and 3 are a side view and a front view, respectively, of the device in use. 1...Element body, 2...Electrode, 3...Slit.

Claims (1)

[Scope of utility model registration request] At least one slit 3 is formed on the tip side of the body 1 of an incomplete combustion detection element consisting of an element body 1 made of zirconia or other material and electrodes 2, 2 on both the front and back sides of the element body 1, and the electrodes 2, 2 on both sides are connected to the element body 1. In at least two sets of slits 3 arranged in parallel on one side and the other side, two adjacent sets of electrodes 2, 2 are connected to the element body 1.
Incomplete combustion is achieved by arranging adjacent electrodes 2, 2 close to each other on both side edges of the slit 3 on the tip side, and widening the gap between adjacent electrodes 2, 2 in the portion extending toward the tail end of the element body 1. Sensing element.