JP2584370B2 - Overvoltage protection element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an overvoltage protection device, and more particularly to an overvoltage protection device which is connected between power supply lines or communication lines constituting an electronic circuit of an electronic device and absorbs overvoltage such as surge applied to the lines. When an overvoltage equal to or higher than the rated voltage of the constant voltage element is continuously applied to the line, the constant voltage element is separated from the line, and at the same time, the line itself is opened to open the load side. The present invention relates to an overvoltage prevention element in which an open circuit element for preventing overvoltage from being applied to a circuit is integrated.

[0002]

2. Description of the Related Art Conventionally, a so-called security circuit, in which a constant voltage element such as a silicon surge absorber is connected between lines constituting a power supply line or a communication line or the like, is interposed in front of an electronic circuit of an electronic device, and an overvoltage such as a surge occurs. Protecting electronic devices from being done. FIG. 21 shows an example in which a constant voltage element a is connected in parallel between lines A and A 'constituting a power supply line or a communication line, and a separation stage is provided at the next stage of the constant voltage element a. Fuse b is connected in series with constant voltage element a. Also, track A
A cutoff fuse c is connected in series to the line A on the input side of the line.

When an overvoltage such as a surge is momentarily applied from the input side to the lines A and A 'provided with the security circuit d having the above configuration, the constant voltage element a operates to reduce the overvoltage. Since the voltage is absorbed, a certain range of voltage is supplied to the electronic circuit e side. Then, when the electronic device is erroneously connected to a power source exceeding its rated voltage, when the communication line is erroneously connected to the power source, or when an overvoltage test is performed assuming such a situation, the above-described situation is caused between the lines A and A '. When an overvoltage equal to or higher than the rated voltage of the constant voltage element a is continuously applied,
In order to prevent short circuit destruction and burning of the constant voltage element a, the separating fuse b is blown and the constant voltage element a is separated from the line A '. Further, after the separation of the constant voltage element a, since the continuous overvoltage may be directly applied to the load side and the electronic circuit e may be destroyed, the breaking fuse c is blown,
The track A itself is opened.

[0004]

Therefore, in order to protect the electronic circuit e from overvoltage, it is necessary to blow the disconnecting fuse c simultaneously with the blowing of the separating fuse b. However, no matter how strict the selection of the separating fuse b and the cutoff fuse c is,
In general, the fusing characteristics of a fuse vary greatly depending on the current value, the application time, and the like. Therefore, there is a possibility that a slight time difference may occur between the time when the disconnecting fuse b is blown and the time when the shutoff fuse c is blown. During this time, an overvoltage is applied to the load side, and there is a risk of damaging the electronic circuit e.

Further, since the security circuit d is constituted by using the constant voltage element a, the separating fuse b and the cutoff fuse c separately, not only the arrangement work becomes complicated, but also
Once the above-mentioned fuse for separation b and fuse for cut-off c are blown out by the application of continuous overvoltage, it is necessary to reconnect the fuse for separation b and fuse for cut-off c, and the recovery work becomes complicated. Met.

An object of the present invention is to solve the above-mentioned problems of the prior art. It is an object of the present invention to open the line itself at the same time as the constant voltage element is separated from the line, and to apply an overvoltage to the load side. It is an object of the present invention to provide an overvoltage protection element which can reliably prevent the application of an overvoltage, has a simple configuration, and can be easily replaced.

[0007]

In order to achieve the above object, an overvoltage protection element according to the present invention is an overvoltage protection element connected between power supply lines or communication lines, and is provided on an insulating substrate. And a silicon surge absorber connected in series with the heating resistor, wherein the heating resistor and the silicon surge absorber are connected to the line. While being inserted between and connected, the conductor is connected in series to the line, and when an overvoltage equal to or higher than the rated voltage of the silicon surge absorber is continuously applied to the line,
The overheating caused by the overvoltage causes the heating resistor to generate heat and break the insulating substrate, whereby the heating resistor and the conductor are simultaneously cut.

An overvoltage protection element connected between lines constituting a power supply line or a communication line, the circuit opening element comprising a heating resistor and a plurality of conductors formed on an insulating substrate. A silicon surge absorber connected in series with the heating resistor. The heating resistor and the silicon surge absorber are inserted and connected between the lines, and at least one of the conductors is connected in series with the line. Connected, and at least one of the other conductors is connected to an external circuit, and when an overvoltage equal to or higher than the rated voltage of the silicon surge absorber is continuously applied to the line, the overheating caused by the overvoltage causes the heating resistor May generate heat and crush the insulating substrate, whereby the heating resistor and the plurality of conductors are simultaneously cut.

Alternatively, there is provided an overvoltage protection element connected between power supply lines or lines constituting a communication line,
A circuit opening element formed by applying a heating resistor and a conductor on an insulating substrate, a silicon surge absorber connected in series with the heating resistor, and an element portion having a connection plug; A socket portion having an external terminal electrically connected to the insertion port, and the element portion and the socket portion are detachable by inserting the connection plug into the insertion port. The heating resistor and the silicon surge absorber are inserted and connected between the lines via the connection plug, the insertion port and the external terminal, and the conductor is connected to the connection plug, the insertion port and the external terminal. When an overvoltage exceeding the rated voltage of the silicon surge absorber is continuously applied to the line through the line, the overcurrent due to the overvoltage causes Heating resistor generates heat by 砕裂 the insulating substrate, the heat generating resistor and the conductor Te following may also be configured to be simultaneously cut.

[0010] Furthermore, an overvoltage protection element connected between lines constituting a power supply line or a communication line, wherein the circuit opening element is formed by applying a heating resistor and a plurality of conductors on an insulating substrate. A silicon surge absorber connected in series with the heating resistor, an element portion having a connection plug, a socket corresponding to the connection plug, and a socket portion having an external terminal electrically connected to the plug. The element part and the socket part are detachably connected by inserting the connection plug into the insertion port, and the heating resistor and the silicon surge absorber are connected to the connection plug, the insertion port, and the outside. At least one of the conductors is connected in series to the line via the connection plug, the insertion port and the external terminal while being inserted and connected between the lines via a terminal. When at least one of the other conductors is connected to an external circuit via the connection plug, the insertion port and the external terminal, and an overvoltage equal to or higher than the rated voltage of the silicon surge absorber is continuously applied to the line, The overheating caused by the overvoltage may cause the heating resistor to generate heat and break the insulating substrate, whereby the heating resistor and a plurality of conductors may be simultaneously cut.

It is preferable that the heating resistor is formed on one surface of the insulating substrate and the conductor is formed on the other surface of the insulating substrate.

The silicon surge absorber may be constituted by a chip type silicon surge absorber, and the chip type silicon surge absorber may be fixed on the insulating substrate.

The "rated voltage" refers to the operating voltage of the silicon surge absorber, and specifically refers to the "breakdown voltage". The expression “applied continuously” means “applied for a certain period of time”, which is an opposite concept of “applied instantaneously”. Therefore, "overvoltage" applied continuously
Naturally includes an AC voltage whose voltage value changes over time. The same applies to the following.

[0014]

When an overvoltage such as a surge is instantaneously applied to the line, the silicon surge absorber operates to absorb the surge. Further, when an overvoltage equal to or higher than the rated voltage of the silicon surge absorber is continuously applied to the line, an overcurrent due to the overvoltage flows through the silicon surge absorber and the overcurrent causes a heating resistance of the open circuit element. Body fever. Then, when the temperature becomes equal to or higher than a predetermined temperature, the insulating substrate is broken by thermal strain, and the heating resistor and the conductor are cut. As a result, the silicon surge absorber connected in series with the heating resistor is disconnected from the line,
The line to which the conductor is connected in series is opened.

A plurality of conductors are formed on the insulating substrate of the open circuit element, at least one of them is connected in series to the line, and at least one of the other conductors is connected to an external circuit. When connected, the line is opened and the external circuit is opened at the same time.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. FIG. 1 shows a first embodiment according to the present invention. A first overvoltage protection element 1 according to this embodiment is roughly divided into a first element section 2 and a first socket section 3. .

The first element section 2 has a first base 4, and a first open circuit element 6 and a silicon surge absorber 7 are provided on an upper surface 5 of the first base 4. Will be installed.
The upper surface 5 of the first base 4 is covered with a cover 8 made of a transparent plastic or the like. Further, as shown in FIG. 2, a first plug 10, a second plug 11 and a third plug 12 are protruded from the bottom surface 9 of the first base 4.

On the upper surface 13 of the first socket portion 3,
The first insertion port 1 having a size and shape corresponding to the first plug 10, the second plug 11, and the third plug 12
4, a second outlet 15 and a third outlet 16 are provided. As shown in FIG. 3, a first external terminal 18, a second external terminal 19, and a third external terminal 20 are protruded from the bottom surface 17 of the first socket portion 3, respectively.

The first plugs 10 to 10 of the first element portion 2
By inserting the third plug 12 into the first insertion port 14 to the third insertion port 16 of the first socket portion 3,
The first element section 2 is detachably connected to the first socket section 3. Further, the first plug 10 to the third plug 1
2 is via the first insertion port 14 to the third insertion port 16,
Each is electrically connected to the first to third external terminals 18 to 20.

As shown in the enlarged views of the main parts of FIGS. 4 and 5, the first circuit open element 6
The first insulating substrate 21 is provided with a first
And a first conductive film 25 (FIG. 5) formed on the back surface 24 of the first insulating substrate 21.

The first insulating substrate 21 is formed of a ceramic such as alumina, forsterite, steatite or the like, and has a thickness of about 0.5 to 1.5 mm.
At the center of the lower side 26 of the first insulating substrate 21, a triangular cutout 27 is formed. The first heating resistance film 23 is formed of a ruthenium-based paste or the like,
Its film thickness is about 10 to 25 μm. The first conductive film 25 is formed of a good electrical conductor such as a silver / palladium (Ag · Pd) paste and has a thickness of 10 to 2 μm.
It is about 5 μm.

A first electrode pattern 28 is formed on the left end of the first heating resistor film 23, and a second electrode pattern 29 is formed on the right end (FIG. 4). . Below the first electrode pattern 28 and the second electrode pattern 29, a first terminal connection portion 30 is provided, respectively.
And a second terminal connection portion 31 are formed, the first terminal 32 is connected to the first terminal connection portion 30, and the second terminal 33 is connected to the second terminal connection portion 31 by soldering or the like. It is fixed (FIG. 4).

A first extension 35 extends from the lower left end of the first conductive film 25, and a second extension 36 extends from the lower right end thereof. A third terminal 39 and a fourth terminal 40 are fixed to the first extension 35 and the second extension 36, respectively, by soldering or the like (FIG. 5).

The first terminal 32, the second terminal 33, the third terminal 39, and the fourth terminal 40 are respectively connected to an inlet 34 formed in the upper surface 5 of the first base 4 through a first port 34. Base 4
Is inserted and connected.

The first connection terminal 41 and the second connection terminal 42 of the silicon surge absorber 7 are connected to the first base 4 through the inlet 34 formed in the upper surface 5 of the first base 4. Is inserted and connected.

The first terminal 3 of the first open circuit element 6
The second to fourth terminals 40, the first connection terminal 41 and the second connection terminal 42 of the silicon surge absorber 7, and the first to third plugs 10 to 12 are connected to the first base 4.
Are connected as follows. That is, although not shown, the first plug 10 and the third terminal 39 of the first open circuit element 6 are first connected. Next, the second plug 11 and the fourth
Terminal 40 and the first terminal 32 are connected. Also,
The second terminal 33 of the first circuit opening element 6 and the first connection terminal 41 of the silicon surge absorber 7 are connected. Finally, the third plug 12 and the second connection terminal 42 of the silicon surge absorber 7 are connected.

The first plug 10 to the third plug 12 of the first element portion 2 having the above configuration are connected to the first to third plugs 14 to 16 of the first socket portion 3. And insert
By coupling the first element part 2 and the first socket part 3, the first overvoltage protection element 1 according to this embodiment is completed. As shown in the circuit diagram of FIG. 6, the first overvoltage protection element 1 includes a pair of lines A and A ′ forming a power supply line or a communication line connected to the electronic circuit 43 of the electronic device.
Connected between them. That is, the first external terminal 18 and the second external terminal 19 of the first socket 3 are connected to the line A, and the third external terminal 20 of the first socket 3 is connected to the line A. Connect to '. As a result, the conductive film 25 of the first circuit open element 6 is connected in series to the line A, and the heating resistor film 23 and the silicon surge absorber 7 connected in series to each other are connected to the line A,
It is connected in parallel between A '. As a result, a first security circuit 44 is formed before the electronic circuit 43.

When an overvoltage such as a surge is instantaneously applied to the lines A and A 'as described above, the silicon surge absorber 7 operates and absorbs the overvoltage. Is always supplied with a certain range of voltage.

When an overvoltage exceeding the rated voltage of the silicon surge absorber 7 is continuously applied, for example, when an electronic device having a rated voltage of 100 V is erroneously connected to a power supply of 200 V, an overcurrent caused by the overvoltage is applied. Flows continuously through the silicon surge absorber 7, and the overheating causes the first heating resistor film 23 of the first circuit open element 6 to generate high heat. Therefore, the first insulating substrate 21
Is rapidly heated, thermal distortion occurs in the first insulating substrate 21, and the first insulating substrate 21 is crushed to the left and right along an extension (b) of the apex of the notch 27 (FIG. 4).

As a result, the first heating resistance film 23 and the first conductive film 25, which are current paths, are cut off, so that the silicon surge absorber 7 is cut off from the line A and the line A is cut off at the same time. The lines A and A 'themselves are opened. Therefore, no overvoltage is applied to the electronic circuit 43.

In the first overvoltage protection element 1 according to the present embodiment, the first element section 2 and the first socket section 3 are detachably connected as described above. When performing a recovery operation after the circuit open element 6 is crushed, it is only necessary to replace only the first element section 2.

Instead of the first open circuit element 6, a second open circuit element 45 shown in FIGS. 7 and 8 may be used. This is characterized in that the third terminal 39 of the first circuit open element 6 is omitted, and the second terminal 33 has the same function. That is, the first branch portion 46 of the second terminal 33 located on the front surface 22 of the first insulating substrate 21 is connected to the second terminal connecting portion 31 (FIG. 7), and the back surface of the insulating substrate 21 is connected. The second branch portion 47 of the second terminal 33 located above the first terminal 24 is connected to the first extension portion 35 of the first conductive film 25 (FIG. 8).

As a result, the second circuit open element 45
A first terminal 32 connected to the first terminal connection unit 30;
It has only three terminals, a second terminal 33 connected to the second terminal connection part 31 and the first extension part 35, and a fourth terminal 40 connected to the second extension part 36. It will be.

Second circuit open element 45 having the above configuration
Although not shown, it is installed on the first base 4 of the first element unit 2 similarly to the first circuit open element 6.
That is, the first terminal 32 of the second circuit open element 45,
The second terminal 33 and the fourth terminal 40 are respectively inserted and connected to the first base 4 from the inlet 34 formed in the upper surface 5 of the first base 4.

The first terminal 32, the second terminal 33, and the fourth terminal 40 of the second circuit open element 45, and the first connection terminal 41 and the second connection terminal 42 of the silicon surge absorber 7 are described. In addition, the first plug 10 to the third plug 12 of the first base 4 are electrically connected to the first base 4 in the same manner as in the above embodiment. However, the connection method is different from that of the above embodiment. That is, the first plug 10 and the fourth terminal 40 are connected, and the second plug 11 and the second terminal 33 are connected. Next, the first terminal 32 is connected to the first connection terminal 41 of the silicon circulative absorber 7, and the second connection terminal 42 is connected to the third plug 12.

The first element section 2 obtained as described above
As described above, the first external terminal 18 and the second external terminal 19 are connected to the line A, and the third external terminal 20 is connected to the first socket portion 3 connected to the line A ′. By doing so, the first security circuit 44 shown in FIG. 6 is formed as in the above embodiment.

According to this embodiment, as described above, the terminals of the second circuit open element 45 include the first terminal 32 and the second terminal
Since only three terminals 33 and the fourth terminal 40 are required, the configuration can be simplified and the production can be facilitated.

Next, another embodiment according to the present invention will be described with reference to FIGS. The second overvoltage protection element 51 according to the present embodiment includes a second element section 52 and a second
The socket part 53 is roughly divided.

The second element section 52 includes a second base 54
The third circuit open element 56 and the silicon surge absorber 7 are arranged on the upper surface 55 of the second base 54. The upper surface 55 of the second base 54 is covered with a second cover 57 made of a transparent plastic or the like. As shown in FIG. 10, a fourth plug 59 and a fifth plug 59 are provided on the bottom surface 58 of the second base 54.
Plug 60, sixth plug 61, seventh plug 62,
A total of six plugs, ie, an eighth plug 63 and a ninth plug 64, are protruded.

On the upper surface 65 of the second socket portion 53, there are provided a fourth insertion port 66 having a size and a shape corresponding to the fourth plug 59 to the ninth plug 64, respectively.
Outlet 67, sixth outlet 68, seventh outlet 69,
An eighth insertion port 70 and a ninth insertion port 71 are provided. As shown in FIG. 11, a fourth external terminal 73, a fifth external terminal 74, a sixth external terminal 75, a seventh external terminal 76,
A total of six external terminals, ie, an eighth external terminal 77 and a ninth external terminal 78 are protruded.

The fourth plug 59 of the second element section 52
By inserting the ninth plug 64 into the fourth insertion port 66 to the ninth insertion port 71 of the second socket section 53, the second element section 52 is connected to the second socket section 53. It is detachably connected to. Further, the fourth plug 59 to the ninth plug 64 are connected to the fourth external terminal 73 to the ninth external terminal 78 via the fourth insertion port 66 to the ninth insertion port 71, respectively. Electrically connected.

The third circuit open element 56 is, as shown in an enlarged view of a main part in FIGS.
9, a substantially rectangular second heat generating resistance film 81 (FIG. 12) formed on the front surface 80 of the second insulating substrate 79, and formed on the back surface 82 of the second insulating substrate 79. The first conductive band 83, the second conductive band 84 and the third conductive band 85
(FIG. 13).

The second insulating substrate 79 is formed of a ceramic such as alumina, forsterite, steatite or the like, and has a thickness of about 0.5 to 1.5 mm.
The second heating resistance film 81 is formed of a ruthenium-based paste or the like, and has a thickness of about 10 to 25 μm. Further, the first conductive band 83, the second conductive band 84, and the third conductive band 85 are made of silver / palladium (Ag
-It is formed of a good electrical conductor such as a Pd-based paste and has a thickness of about 10 to 25 m.

A third electrode pattern 86 and a fourth electrode pattern 87 are formed along both long sides of the second heating resistance film 81, respectively. A first L-shaped terminal 89 is fixed to the third terminal connection portion 88 of the third electrode pattern 86 by soldering or the like, and is connected to the fourth terminal connection portion 90 of the fourth electrode pattern 87. The second L-shaped terminal 91 is fixed by soldering or the like (FIG. 12).

On the other hand, a third L-shaped terminal 92 and a fourth L-shaped terminal 93 are provided at both ends of the first conductive band 83, and a fifth L-shaped terminal 93 is provided at both ends of the second conductive band 84. A terminal 94 and a sixth L-shaped terminal 95, and a seventh L-shaped terminal 96 and an eighth L-shaped terminal 97 at both ends of the third conductive band 85.
Are fixed by solder or the like (FIG. 1)
3).

The first L-shaped terminal 89 to the eighth L-shaped terminal 97 are respectively inserted into the second base 54 from the inlet 34 formed in the upper surface 55 of the second base 54. Connected. Then, the first L-shaped terminal 8 of the third circuit opening element 56 inserted and connected from the introduction port 34 to the second base 54.
9th to 8th L-shaped terminals 97, the first connection terminal 41 and the second connection terminal 42 of the silicon surge absorber 7,
The fourth plug 59 to the ninth plug 64 of the second base 54 are electrically connected to each other at the second base 54.

That is, although not shown, first, the fourth plug 59 and the third L-shaped terminal 92 are connected, and the fifth plug 60, the fourth L-shaped terminal 93 and the first L-shaped terminal 93 are connected.
L-shaped terminal 89 is connected. Further, the second L-shaped terminal 91 and the first connection terminal 41 of the silicon surge absorber 7 are connected. Next, the sixth plug 61 and the fifth L-shaped terminal 94 are connected, and the seventh plug 62 and the sixth L-shaped terminal 95 and the second connection terminal 42 of the silicon surge absorber 7 are connected. Are connected. Further, the eighth plug 63 and the seventh L-shaped terminal 96 are connected, and the ninth plug 64 and the eighth L-shaped terminal 9 are connected.
7 is connected.

The fourth element 52 of the second element section 52 having the above configuration
The plug 59 to the ninth plug 64 are inserted into the fourth insertion port 66 to the ninth insertion port 71 of the second socket portion 53, and the second element portion 52 and the second socket The second overvoltage protection element 51 according to the present embodiment is completed by coupling the second overvoltage protection element 51 to the section 53.

As shown in the circuit diagram of FIG. 14, the second overvoltage protection element 51 is first connected between the lines A and A 'leading to the electronic circuit 43 of the electronic device. That is, the second
The fourth external terminal 73 and the fifth external terminal 74 of the socket section 53 are connected to the line A, and the sixth external terminal 75 and the seventh external terminal 76 are connected to the line A ′. As described above, the first conductive band 83 and the second conductive band 8
4 are connected in series to the line A and the line A ', respectively, and the second heating resistance film 81 and the silicon surge absorber 7 connected in series to each other are connected in parallel between the lines A and A'. As a result, a second security circuit 98 is formed before the electronic circuit 43.

The eighth external terminal 77 and the ninth external terminal 78 of the second socket 53 are connected to an external circuit 99 separate from the second security circuit 98. As a result,
A third conductive band 85 is connected to the external circuit 99 in series.
The external circuit 99 is, for example, an abnormality monitoring circuit to which the monitor 100 is connected.

When an overvoltage exceeding the rated voltage of the silicon surge absorber 7 is continuously applied to the lines A and A ', an overcurrent due to the overvoltage flows through the silicon surge absorber 7, and The second heat generating resistive film 81 generates heat by an electric current and breaks the second insulating substrate 79. As a result, the second heating resistance film 81
Is cut off, and the silicon surge absorber 7 connected in series with this is separated from the line A, so that short-circuit and burnout can be prevented. At the same time, the first conductive band 83 and the second conductive band 84 are also cut, so that the lines A and A 'are cut off, and the lines A and A' themselves are opened. Further, since the third conductive band 85 is also cut,
The external circuit 99 is also opened at the same time.

As described above, according to the present embodiment, the lines A and A 'can be cut off at two places simultaneously with the separation of the silicon surge absorber 7, so that the electronic circuit 43 can be more reliably protected from overvoltage. In addition, since the external circuit 99 can be opened in conjunction with the opening of the lines A and A ′, the abnormal situation can be displayed on the monitor 100 in real time.

In this embodiment, an example in which three conductive bands are formed as described above has been described. However, the present invention is not limited to this. By forming more conductive bands, a plurality of conductive bands can be formed. May be configured to open the external circuit.
Further, it is not always necessary to cut off the lines A and A 'at two places, and it is sufficient to cut off at least one place. Therefore, the remaining conductive band may be allocated to open an external circuit.

In this embodiment, the external circuit 99 is configured as an abnormality monitoring circuit to which the monitor 100 is connected as described above. However, the present invention is not limited to this, and the opening of the second security circuit 98 is not limited to this. May be configured to control other devices in conjunction with.

Another embodiment according to the present invention will be described with reference to FIGS. The third overvoltage protection element 101 according to the present embodiment includes a third insulating substrate 102, a third heating resistance film 104 (FIG. 15) formed on the front surface 103 of the third insulating substrate 102, and , The third insulating substrate 102
And a second conductive film 106 (FIG. 16) formed on the back surface 105 of the second conductive film.

The third insulating substrate 102 is made of alumina,
It is formed of a ceramic such as forsterite or steatite, and has a thickness of about 0.5 to 1.5 mm. At the center of the lower side 107 of the third insulating substrate 102, a triangular cutout 108 is formed. The third heating resistance film 104 is formed of a ruthenium-based paste or the like, and has a thickness of about 10 to 25 μm.
The second conductive film 106 is made of silver / palladium (Ag · P
d) It is formed of a good electrical conductor such as a paste and has a thickness of about 10 to 25 μm.

A fifth electrode pattern 109 is formed on the left end of the third heating resistor film 104, and a sixth electrode pattern 110 is formed on the right end (FIG. 15). . A fifth terminal connection portion 111 is formed below the fifth electrode pattern 109, and a fifth terminal 112 is fixed to the fifth terminal connection portion 111 by soldering or the like (FIG. 15). . Further, an upper end of a chip-type silicon surge absorber 114 is connected to a connection portion 113 below the sixth electrode pattern 110,
A conductive pattern 115 is connected to the lower end of the chip type silicon surge absorber 114. The chip-type silicon surge absorber 114 is connected to the third insulating substrate 10.
2 is fixed to the front surface 103. The above conductive pattern 1
A sixth terminal 116 is fixed to 15 by soldering or the like (FIG. 15).

A third extension 117 extends from the lower left end of the second conductive film 106, and a fourth extension 118 extends from the lower right end thereof. A seventh terminal 121 and an eighth terminal 122 are fixed to the third extension 117 and the fourth extension 118 by soldering or the like, respectively (FIG. 16).

Third overvoltage protection element 1 having the above configuration
17, the third security circuit 1 as shown in FIG.
23 can be configured. That is, by connecting the seventh terminal 121 and the eighth terminal 122 to the line A, the second conductive film 106 is connected to the line A in series. In addition, by connecting the sixth terminal 116 to the line A and connecting the fifth terminal 112 to the line A ′, the chip-type silicon surge absorber 114 and the third heat-generating element are connected in series. Resistive film 1
04 is connected in parallel between the lines A and A '.

When an overvoltage such as a surge occurs in the line A,
When the voltage is applied to A ′ instantaneously, the chip-type silicon surge absorber 114 operates to absorb this overvoltage, and thus a voltage in a certain range is always supplied to the electronic circuit 43 side.

When an overvoltage equal to or higher than the rated voltage of the chip-type silicon surge absorber 114 is continuously applied, an overcurrent caused by the overvoltage continuously flows through the chip-type silicon surge absorber 114, The third heating resistor film 104 generates high heat by the current, and rapidly heats the front surface 103 of the third insulating substrate 102. On the other hand, since the second conductive film 106 is formed of a good electrical conductor, it hardly generates heat even when an overcurrent flows continuously,
The temperature of 5 does not change. Therefore, the third insulating substrate 10
2 causes thermal distortion, and the extension line of the top of the notch 108 (c)
The third insulating substrate 102 is crushed to the left and right along the line (FIG. 16).

As a result, the third heat generating resistive film 104 and the second conductive film 106, which are current paths, are cut off.
At the same time that the chip type silicon surge absorber 114 is disconnected from the line A ′, the line A is also disconnected and the lines A,
A 'itself is released. Therefore, no overvoltage is applied to the electronic circuit 43.

As described above, by fixing the chip type silicon surge absorber 114 on the third insulating substrate 102, the structure can be simplified and the element can be downsized.

Instead of the third overvoltage protection element 101, the fourth overvoltage protection element 12 shown in FIGS.
4 may be used. This is characterized in that the seventh terminal 121 of the third overvoltage protection element 101 is omitted, and the function of the sixth terminal 116 is also used.
That is, the first branch portion 125 of the sixth terminal 116 located on the front surface 103 of the third insulating substrate 102 is connected to the conductive pattern 115 (FIG. 18), and
05 and the second extension 126 located above the third extension 1
17 (FIG. 19).

As a result, the fourth overvoltage protection element 124
Is the fifth terminal 1 connected to the fifth terminal connection unit 111
12, a sixth terminal 116 connected to the conductive pattern 115 and the third extension 117, and an eighth terminal 122 connected to the fourth extension 118, for a total of only three terminals. Becomes

The fourth overvoltage protection element 1 having the above configuration
24, the fourth security circuit 1 as shown in FIG.
27 can be configured. That is, by connecting the sixth terminal 116 and the eighth terminal 122 to the line A, the second conductive film 106 is connected to the line A in series. Further, by connecting the fifth terminal 112 to the line A ′, the chip-type silicon thermistor absorber 114 and the third heating resistor film 104 connected in series to each other are connected.
Are connected in parallel between the lines A and A ′.

The fourth overvoltage protection element 12 according to this embodiment
4 also applies to the third
The same function as that of the overvoltage protection element 101 of FIG. That is, when an overvoltage such as a surge is instantaneously applied to the lines A and A ', the chip-type silicon surge absorber 114 operates to absorb the overvoltage.

When an overvoltage equal to or higher than the rated voltage of the chip-type silicon surge absorber 114 is continuously applied, the third heat-generating resistive film 104 sharply covers the front surface 103 of the third insulating substrate 102. Because of heating, the third insulating substrate 102 is crushed right and left. As a result, the third heating resistance film 104 and the second conductive film 1 which are current paths are formed.
06 is disconnected, the chip-type silicon surge absorber 114 is disconnected from the line A ′, and
Is also disconnected, and the lines A and A 'themselves are opened. Therefore, no overvoltage is applied to the electronic circuit 43 side.

The fourth overvoltage protection element 12 according to this embodiment
According to No. 4, since only five terminals, the fifth terminal 112, the sixth terminal 116, and the eighth terminal 122, are required, the configuration can be simplified and manufacturing can be facilitated.

[0070]

According to the overvoltage protection device of the present invention, when an overvoltage equal to or higher than the rated voltage of the silicon surge absorber is continuously applied to the line to which the silicon surge absorber is connected, the overcurrent caused by the overvoltage is reduced. As a result, the heating resistor of the circuit open element rapidly heats the insulating substrate to break it, and cuts the heating resistor connected in series to the silicon surge absorber and the conductor connected in series to the line. With this configuration, the line is opened at the same time that the silicon circulator is separated from the line.
Therefore, it is possible to reliably prevent an overvoltage from being applied to the load after the silicon surge absorber is disconnected from the line.

Further, since the circuit open element and the silicon surge absorber are realized as an integrated element, the manufacturing process can be simplified.

An element part in which a circuit open element, a silicon thermistor absorber and a connection plug are integrated, and a socket part having an insertion port and an external terminal are attached and detached by inserting the connection plug into the insertion port. By being configured so as to be freely coupled, recovery work after the crushing of the insulating substrate can be facilitated.

A plurality of conductors are formed on an insulating substrate constituting an open circuit element, at least one of the conductors is connected in series to the line, and at least one of the other conductors is connected to an external circuit. , The external circuit can be opened in conjunction with the opening of the line.

The above-mentioned silicon surge absorber is constituted by a chip type silicon surge absorber, and the chip type silicon surge absorber is fixed on an insulating substrate constituting a circuit open element, thereby simplifying the structure and downsizing the element. I can do it.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing a first overvoltage protection device according to one embodiment of the present invention.

FIG. 2 is a schematic perspective view showing a first element section according to the embodiment.

FIG. 3 is a schematic perspective view showing a first socket portion according to the embodiment.

FIG. 4 is a schematic front perspective view showing a first circuit open element according to the embodiment.

FIG. 5 is a schematic rear perspective view showing a first open circuit element according to the embodiment.

FIG. 6 is a circuit diagram according to the embodiment.

FIG. 7 is a schematic front perspective view showing a second circuit open element according to another embodiment of the present invention.

FIG. 8 is a schematic rear perspective view showing a second circuit open element according to the embodiment.

FIG. 9 is a schematic perspective view showing a second overvoltage protection device according to another embodiment of the present invention.

FIG. 10 is a schematic perspective view showing a second element section according to the embodiment.

FIG. 11 is a schematic perspective view showing a second socket portion according to the embodiment.

FIG. 12 is a schematic front perspective view showing a third circuit open element according to the embodiment.

FIG. 13 is a schematic rear perspective view showing a third circuit open element according to the embodiment.

FIG. 14 is a circuit diagram according to the embodiment.

FIG. 15 is a schematic front perspective view showing a third overvoltage protection device according to another embodiment of the present invention.

FIG. 16 is a schematic rear perspective view showing a third overvoltage protection element according to the embodiment.

FIG. 17 is a circuit diagram according to the embodiment.

FIG. 18 is a schematic front perspective view showing a fourth overvoltage protection element according to another embodiment of the present invention.

FIG. 19 is a schematic rear perspective view showing a fourth overvoltage protection element according to the above embodiment.

FIG. 20 is a circuit diagram according to the embodiment.

FIG. 21 is a circuit diagram according to a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st overvoltage protection element 2 1st element part 3 1st socket part 6 1st circuit opening element 7 Silicon surge absorber 10 1st plug 11 2nd plug 12 3rd plug 14 1st difference Entrance 15 Second outlet 16 Third outlet 18 First external terminal 19 Second external terminal 20 Third external terminal 21 First insulating substrate 23 First heating resistor film 25 First 45 Second circuit open element 51 Second overvoltage prevention element 52 Second element part 53 Second socket part 56 Third circuit open element 59 Fourth plug 60 Fifth plug 61 Sixth Plug 62 Seventh plug 63 Eighth plug 64 Ninth plug 66 Fourth outlet 67 Fifth outlet 68 Sixth outlet 69 Seventh outlet 70 Eighth outlet Port 71 Ninth insertion port 73 Fourth external terminal 7 4 Fifth External Terminal 75 Sixth External Terminal 76 Seventh External Terminal 77 Eighth External Terminal 78 Ninth External Terminal 79 Second Insulating Substrate 81 Second Heating Resistive Film 83 First Conductive Band 84 Second conductive band 85 Third conductive band 99 External circuit 101 Third overvoltage protection element 102 Third insulating substrate 104 Third heat generating resistive film 106 Second conductive film 114 Chip type silicon surge absorber 124 Fourth Overvoltage protection element

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical display location H04B 3/00 H04B 3/00 (56) References JP-A-2-65620 (JP, A) Opened 63-257416 (JP, A) Opened 55-120063 (JP, U) Opened 63-29343 (JP, U) Opened 49-19231 (JP, U) Opened 62-193647 (JP, U) JP, U)

Claims (6)

(57) [Claims] 1. An overvoltage protection element connected between power supply lines or communication lines, said circuit opening element comprising a heating resistor and a conductor formed on an insulating substrate. Silicon circuit connected in series with heating resistor
It and a di-absorber, the heat generating resistor and Siri
The surge absorber is inserted and connected between the lines, and the conductor is connected in series to the line, and when an overvoltage equal to or higher than the rated voltage of the silicon surge absorber is continuously applied to the line, the overvoltage An overvoltage protection element configured so that the heating resistor generates heat due to an overcurrent caused by the above and breaks the insulating substrate, thereby simultaneously cutting the heating resistor and the conductor. 2. An overvoltage protection element connected between lines constituting a power supply line or a communication line, the circuit opening element comprising a heating resistor and a plurality of conductors formed on an insulating substrate. , Silicon connected in series with the heating resistor
The heat generating resistor and the silicon surge absorber are inserted and connected between the lines, at least one of the conductors is connected in series to the line, and at least one of the other conductors is connected to the line. One is connected to an external circuit, and when an overvoltage equal to or higher than the rated voltage of the silicon surge absorber is continuously applied to the line,
An overvoltage protection element configured such that the overheating caused by the overvoltage causes the heating resistor to generate heat and break the insulating substrate, thereby simultaneously cutting the heating resistor and a plurality of conductors. 3. An overvoltage protection element connected between lines constituting a power supply line or a communication line, wherein the circuit opening element is formed by forming a heating resistor and a conductor on an insulating substrate. Silicon surge connected in series with resistor
An element having an absorber and a connection plug, an insertion port corresponding to the connection plug, and a socket having an external terminal electrically connected to the insertion, the element and the socket being Is connected detachably by inserting the connection plug into the insertion port, and the heating resistor and the silicon surge absorber are inserted and connected between the lines via the connection plug, the insertion port and external terminals. In addition, the conductor is connected in series to the line via the connection plug, the insertion port and the external terminal, and when an overvoltage equal to or higher than the rated voltage of the silicon surge absorber is continuously applied to the line, An overcurrent generated by the overheating caused by the overvoltage, the heating resistor being heated to break the insulating substrate, whereby the heating resistor and the conductor are simultaneously cut off; Stop element. 4. An overvoltage protection element connected between lines constituting a power supply line or a communication line, the circuit opening element comprising a heating resistor and a plurality of conductors formed on an insulating substrate. Silicon connected in series with the heating resistor
An element portion having a surge absorber and a connection plug;
An insertion port corresponding to the connection plug, and a socket portion having an external terminal electrically connected to the insertion port, the element portion and the socket portion, the connection plug to the insertion port It is detachably connected by inserting,
The heating resistor and the silicon surge absorber are inserted and connected between the lines via the connection plug, the insertion port and the external terminal, and at least one of the conductors connects the connection plug, the insertion port and the external terminal. And at least one of the other conductors is connected to an external circuit through the connection plug, the insertion port and the external terminal, and an overvoltage equal to or higher than the rated voltage of the silicon surge absorber is applied to the line. When applied continuously, the overheating caused by the overvoltage causes the heating resistor to generate heat and crush the insulating substrate, whereby the heating resistor and a plurality of conductors are simultaneously cut. Overvoltage protection element. 5. The heating resistor is formed on one surface of the insulating substrate, and the conductor is formed on the other surface of the insulating substrate. 5. The overvoltage protection element according to any one of 1 to 4. 6. The silicon surge absorber according to claim 1, wherein the silicon surge absorber is formed of a chip type silicon surge absorber , and the chip type silicon surge absorber is fixed on the insulating substrate. Overvoltage protection element.