JP2556097Y2 - Laminated structure of paste wiring and surge absorber using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application field] The present invention relates to a laminated structure of a paste wiring and a surge absorber using the same, and particularly, connection of a resistance layer to which a voltage exceeding a rated voltage may be applied. In addition, a surge absorber that absorbs a surge that is about to enter a telephone or the like by the discharge phenomenon of a discharge gap sealed in an airtight container, especially when a continuous excessive surge is input, etc. The present invention relates to a laminated structure of paste wiring in which a surge absorbing element is separated from a circuit to ensure safety and a surge absorber using the same.

[Related Art] In recent years, various laminated structures have been proposed in which a semi-kneaded resistive material is solidified on a substrate, a paste conductive layer is laminated on the paste resistor, and wiring is performed.

[Problem to be solved by the invention] However, in the wiring configured by such a manufacturing method,
The contact resistance between the paste resistance layer and the paste conductive layer is large, and a hot spot may be formed due to an overcurrent, resulting in burning.

By the way, in a discharge type surge absorber, a resistor connected in series with a surge absorbing element is attached to a line such as a telephone line where a surge is likely to occur, but a large current due to a continuous excessive surge may flow. When current flows due to an abnormal voltage generated when a line touches a transmission line or the like, a pattern may be burned out in a resistor manufactured by a conventional method.

The present invention has been made in view of the above points, and has a reduced contact resistance between a paste resistance layer and a paste conductive layer, so that a paste wiring laminated structure that does not have a risk of forming a hot spot due to overcurrent. It is another technical object of the present invention to provide a surge absorber using the laminated structure of the paste wiring.

[Means for Solving the Problems] The present invention has the following configuration in order to solve the above technical problem.

That is, in the first configuration example, a first paste conductive layer is formed on one surface of an insulating substrate, and a paste resistance layer partially laminated on the first paste conductive layer is formed on one surface of the insulating substrate. And a second paste conductive layer is laminated on the surface of the paste resistance layer located on the first paste conductive layer, and the insulating substrate is subjected to thermal strain caused by heat generation of the paste resistance layer caused by continuous overcurrent. A laminate structure of paste wiring formed of crackable alumina, forsterite or steatite ceramic, and having the paste resistance layer disposed on the first paste conductive layer so as to be cut when the insulating substrate is broken. It is.

In the second configuration example, a surge absorbing element is disposed on an insulating substrate, a first paste conductive layer is formed on one surface of the insulating substrate, and a part of the first paste conductive layer is formed on the first paste conductive layer. A paste resistance layer to be laminated is formed on one surface of the insulating substrate, and a second paste conductive layer is further laminated on the paste resistance layer located on the first paste conductive layer. The first paste is formed of alumina, forsterite, or steatite-based ceramic that is broken by thermal distortion caused by heat generated by the paste resistance layer caused by an overcurrent, and the first paste is cut so that the paste resistance layer is cut when an insulating substrate is cracked. The surge absorbing element and the paste resistance layer are arranged on the conductive layer, and further connected in series through the paste conductive layers formed at both ends of the paste resistance layer. It is an surge absorber.

[Operation] In the first configuration, since the paste resistance layer and the first and second paste conductive layers have a so-called sandwich structure, the contact resistance between the paste resistance layer and the paste conductive layer is low, and a hot spot hardly occurs. That is, even if the paste resistance layer generates heat due to continuous overcurrent, there is no disconnection at a connection portion (a portion where a hot spot occurs) between the paste resistance layer and the paste conductive layer. On the other hand, when the paste resistance layer generates heat due to continuous overcurrent, only one side of the insulating substrate on which the paste resistance layer is formed expands by heating, and heat is applied to the insulating substrate formed of alumina, forsterite, or steatite ceramic. Distortion occurs and cracks, which also cut the paste resistance layer.

In the second configuration, a continuous overvoltage (for example, an AC voltage in a safety standard test) is applied to the paste resistance layer, and when an overcurrent due to this voltage flows and the paste resistance layer generates heat, the paste resistance layer is formed. Only one surface of the insulating substrate is heated and expanded, and the insulating substrate formed of alumina, forsterite or steatite ceramic is thermally strained and cracked, thereby cutting the paste resistance layer. It is cut off from the circuit and can automatically prevent overheating.

Embodiment An embodiment of the present invention will be described with reference to FIGS.

<First Configuration Example> As shown in FIG. 1, a first paste conductive layer 4 is formed on one surface of a ceramic insulating substrate 1 using an Ag.Pd-based paste. Then, a part of the paste resistance layer 3 based on the ruthenium-based paste resistance is laminated on the surface of the first paste conductive layer 4 and extends on the insulating substrate. Furthermore, the paste resistance layer 3
The second paste conductive layer 8 is formed by superimposing on the laminated portion of the first paste conductive layer 4 and the first paste conductive layer 4. This second paste conductive layer 8
Are integrated with the first paste conductive layer 4 to form wiring terminals. As a result, the contact resistance is halved as compared with the case where the paste resistance layer and the paste conductive layer are simply overlapped, and there is no possibility that a hot spot is generated by heating at the connection portion. Therefore, the paste resistance layer 3 does not break at the portion where the hot spot occurs. On the other hand, when the paste resistance layer 3 generates heat due to continuous overcurrent, only one surface of the insulating substrate 1 on which the paste resistance layer 3 is formed expands due to heat, so that thermal distortion occurs in the insulating substrate 1 and cracks occur.
At the same time, the paste resistance layer 3 is also cut.

<Second Configuration Example> In a second configuration example, a surge absorber applying the first configuration example will be described.

In other words, the surge absorber consists of a surge absorbing element and a resistor connected in series with it, but if a continuous alternating current is input as in a safety standard test, the surge absorbing element or the resistor will burn out. May be. In such a case, it is desirable that the surge absorbing element be automatically disconnected from the circuit.However, if the resistor is burned out and the circuit is disconnected, the reproducibility will be lacking and individual characteristics will vary. Become.

A description will be given below of a surge absorber in which a danger such as overheating of the surge absorbing element does not occur, and which can obtain safe characteristics.

First, the surge absorbing element 2 is disposed on the surface of a ceramic substrate 1 made of alumina. On the other hand, a paste resistance layer 3 of a ruthenium-based paste is formed on the back surface of the ceramic substrate 1. The paste resistance layer 3 is formed in a meandering manner as shown in FIG. 3, and both ends of the paste resistance layer 3 are made of Ag / Pd-based paste as described in the first configuration example.
Paste conductive layers 4 and 8 are laminated in the sandwich structure described above. A second paste conductive layer 8 is laminated on the first paste conductive layer 4 with the paste resistance layer 3 interposed therebetween, and the second paste conductive layer 8 on one end side is soldered to one end of the surge absorbing element 2. Connected to The second paste conductive layer 8 on the other end is connected to the lead wire 6 by solder 5. The other end of the surge absorbing element 2 is a lead wire 7.

Thus, the surge absorbing element 2 and the paste resistance layer 3 are connected in series as shown in the equivalent circuit diagram of FIG.
A glass layer 9 made of borosilicate glass for preventing creeping discharge is formed on the paste resistance layer.

In the above embodiment, the surge absorbing element 2 and the paste resistance layer 3 are provided on different surfaces of the ceramic substrate 1, respectively, but they may be provided on the same surface.

In the above-described configuration, when a continuous excessive surge is applied between the lead wires 6 and 7 or an AC voltage is continuously applied by a withstand voltage test, discharge occurs in the surge absorbing element 2 and the paste resistance layer 3 is removed. Start fever. Then, the ceramic substrate 1 is heated and expanded only on the surface on which the paste resistance layer 3 is formed. On the other hand, since the surface on which the surge absorbing element 2 is provided does not generate much heat, the surface of the ceramic substrate is cracked due to thermal distortion. At the same time, the paste resistance layer 3 is also cut, and the surge absorbing element 2 is cut off from the circuit. At this time, the contact resistance with the paste conductive layers 4 and 8 is sufficiently low, and there is no fear that heat is generated and the wire is disconnected.

As described above, when continuous AC or DC is applied, the circuit is automatically cut, and abnormal overheating can be prevented.

As the ceramic substrate, a substrate having a large coefficient of thermal expansion and being easily cracked is suitable. In addition to the above-described substrates, forsterite or steatite-based substrates can be used. The resistance value of the paste resistance layer 3 is 1Ω to 300Ω.
The range of the degree is suitable, and can be appropriately set depending on the use conditions. Further, the glass layer 9 may be formed of a lead-free glass such as bismuth glass, and it is not always necessary to provide this layer.

According to the first configuration of the present invention, the paste resistance layer and the first
And the second paste conductive layer has a so-called sandwich structure, so that the contact resistance is low and hot spots are generated and separated, and even if the paste resistance layer generates heat due to continuous overcurrent, the paste resistance layer and the paste conductive layer There is no disconnection at the connection part (where a hot spot occurs).

Further, according to the second configuration, a continuous overvoltage (for example, an AC voltage in a safety standard test) is applied to the paste resistance layer, and when an overcurrent due to this voltage flows and the paste resistance layer generates heat, the paste resistance layer is formed. Only one side of the insulating substrate heats and expands, causing thermal strain on the insulating substrate formed of alumina, forsterite or steatite ceramics, which breaks the paste resistive layer. The element is disconnected from the circuit and can automatically prevent heating.

[Brief description of the drawings]

1 to 4 show an embodiment of the present invention. FIG. 1 is a sectional view of a main part, FIG. 2 is a perspective view of a second configuration example, FIG. 3 is a bottom view of a ceramic substrate, and FIG. The figure is an equivalent circuit diagram. DESCRIPTION OF SYMBOLS 1 ... Ceramic substrate as an insulating substrate, 2 ... Surge absorption element, 3 ... Paste resistance layer, 4 ... 1st paste conductive layer, 8 ... 2nd paste conductive layer.

Claims (3)

(57) [Scope of request for utility model registration] A first paste conductive layer is formed on one surface of an insulating substrate, and a paste resistance layer partially laminated on the first paste conductive layer is formed on one surface of the insulating substrate. An alumina which is obtained by laminating a second paste conductive layer on the surface of the paste resistive layer located on the first paste conductive layer, and wherein the insulating substrate is divided by thermal strain caused by heat generation of the paste resistive layer caused by continuous overcurrent; A laminated structure of a paste wiring, wherein the laminated structure is made of forsterite or steatite ceramic, and the paste resistance layer is arranged on the first paste conductive layer so as to be cut when the insulating substrate is broken. 2. A paste in which a surge absorbing element is disposed on an insulating substrate, a first paste conductive layer is formed on one surface of the insulating substrate, and a part of the first paste conductive layer is laminated on the first paste conductive layer. A resistive layer is formed on one surface of the insulating substrate, and a second paste conductive layer is laminated on the paste resistive layer located on the first paste conductive layer. The paste resistance layer is formed of alumina, forsterite, or steatite-based ceramic that is broken by thermal distortion caused by heat generated by the paste resistance layer, and the paste resistance layer is cut on the first paste conductive layer so as to be cut when the insulating substrate is cracked. And that the surge absorbing element and the paste resistance layer are connected in series via paste conductive layers formed at both ends of the paste resistance layer. Surge absorber to the butterflies. 3. The surge absorber according to claim 2, wherein a glass layer is formed on said paste resistance layer.