JP2019193367A - Separator incorporating spd - Google Patents

Abstract

To provide a separator incorporating SPD which has an excellent operation accuracy and high reliability.SOLUTION: The separator incorporating SPD has a series circuit including a striker incorporating current fuse 20 serving as an overcurrent separator, a conductor 30 serving as a thermal separator which is separated during overheating of a varistor 40, and the varistor 40, and detects a failure on the basis of a mechanical operation of the overcurrent separator or thermal separator. The separator incorporating SPD includes a first slider 23 that, when struck by an outward protruding striker 22, moves in a certain direction against a restoring force of a first spring 29, an alarm contact output microswitch 53 that is turned on by movement of the slider 23, a motion displaying display section 55 that moves when released from locking with the slider 23 by movement of the slider 23, and a second slider 31 that moves the first slider 23 with a restoring force of a second spring 32 when released from locking with the conductor 30 at the separation time of the conductor 30.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an SPD (Surge Protective Device) incorporating a separator comprising an overcurrent separator and a heat separator.

FIG. 7 is a block diagram showing a conventional technique of this type of separator built-in SPD.
In FIG. 7, an SPD 100 includes an overcurrent separator 111, a heat separator 121, a metal oxide varistor (: MOV, hereinafter) connected between one AC line 151 to which a single-phase AC voltage is applied and a ground point G. (Also simply referred to as a varistor) 131 and a second series consisting of an overcurrent separator 112, a heat separator 122, and a varistor 132 connected between the other AC line 152 and the ground point G. A failure detection circuit 140 is connected between the first and second series circuits.

  Here, the overcurrent separators 111 and 112 are configured by current fuses that are blown by an overcurrent such as a short-circuit current, and the thermal separators 121 and 122 are connected to their terminals due to heat generated due to deterioration of the varistors 131 and 132. The electrical connection portion (solder) is composed of a conductor or a thermal fuse that melts and separates.

A voltage between the AC lines 151 and 152 is applied to the failure detection circuit 140 via the overcurrent separators 111 and 112 and the heat separators 121 and 122.
For example, when the varistor 131 or 132 deteriorates and generates heat and the heat separator 121 or 122 is separated, or when the overcurrent flows through the varistor 131 or 132 and the overcurrent separator 111 or 112 is melted, The voltage applied to the failure detection circuit 140 changes. Since these applied voltages are different from the normal ones, the failure detection circuit 140 electrically detects a failure of the SPD 100 (deterioration of the varistor 131 or 132, etc.) and performs failure display and alarm contact output.

  In the above prior art, it is not possible to determine whether the circuit is interrupted due to the operation of the overcurrent separators 111 and 112 or the heat separators 121 and 122 and the power supply circuit to the failure detection circuit 140 is interrupted due to a power failure. For this reason, there is a possibility that the failure detection circuit 140 may perform failure display or alarm contact output of the SPD 100 during a power failure.

Patent Document 1 describes a direct lightning SPD in which a separator composed of a thermal fuse as a thermal separator and a disconnected conductor as an overcurrent separator is connected in series to a metal oxide varistor (zinc oxide varistor). ing.
FIG. 8 is a schematic circuit diagram of the direct lightning SPD. 200 is an SPD, 201 and 202 are terminals connected to an AC line and a ground point, 203 is a varistor, and 204 is a thermal fuse 204A. , A separator composed of a disconnecting conductor 204B that functions as a current fuse, and 205 is a display unit that displays the operation of the separator 204.

  FIG. 9 is a diagram for explaining the operation of this direct lightning SPD. FIG. 9A shows the operation when the thermal fuse 204A is blown, and FIG. 9B shows the operation when the disconnecting conductor 204B is separated. In these figures, 203a is a filler in which the varistor 203 is embedded, 206 is a microswitch for outputting an alarm, and 207 is a coil spring.

  In this conventional technique, the restoring force of the coil spring 207 is used to make the display unit 205 almost undisturbed when the thermal fuse 204A is blown (FIG. 9A) and when the disconnected conductor 204B is separated (FIG. 9B). By moving only the same stroke, the tip of the display unit 205 is projected to the outside to display an operation, and the micro switch 206 is turned on to output an alarm contact.

JP 2007-288114 A (paragraphs [0035], [0036], FIG. 1, FIG. 6, FIG. 7, etc.)

  As described above, in the conventional technique of FIG. 7, the failure detection circuit 140 detects a failure electrically, whereas in the conventional techniques of FIGS. 8 and 9 described in Patent Document 1, the thermal fuse 204A is used. Fault indication and alarm contact output are made possible by the OR condition between the mechanical operation due to melting and the mechanical operation due to separation of the separation conductor 204B.

However, in the prior art shown in FIGS. 8 and 9, the disconnecting conductor 204 </ b> B that functions as a current fuse is a plate-like conductor, and therefore cannot block a large short-circuit current. Therefore, the direct lightning SPD according to the prior art needs to connect an external overcurrent separator (current fuse) in series with the direct lightning SPD. In this case, when performing failure display or alarm contact output, it is necessary to perform failure display or alarm contact output from an external separator.
Therefore, the problem to be solved by the present invention is that both an overcurrent separator and a heat separator capable of interrupting a large short-circuit current are mounted inside the SPD, and either one or both of the overcurrent separator and the heat separator are operated. It is another object of the present invention to provide an SPD with a built-in separator that performs fault indication and / or alarm contact output.

In order to solve the above-mentioned problem, the invention according to claim 1 separates the current fuse as an overcurrent separator in which a striker protrudes to the outside when the fuse body melts due to overcurrent and the terminal of the varistor when the varistor is overheated. A series circuit comprising a conductor as a heat separator and the varistor,
In the SPD with a built-in separator that detects a failure based on the mechanical operation of the overcurrent separator or the mechanical operation of the thermal separator,
A first slider that is struck by the striker protruding outward and moves in a certain direction while resisting the restoring force of the first spring;
A switch for alarm contact output that is turned on by the movement of the first slider in the fixed direction;
A second slider that is unlocked when the conductor is separated and moves in the fixed direction by a restoring force of a second spring, and moves the first slider in the fixed direction. It is characterized by that.

  According to a second aspect of the present invention, in the SPD with a built-in separator according to the first aspect, the first slider is released from being locked with the first slider and is movable. A display unit for displaying an operation is further provided.

  The invention according to claim 3 is the SPD with built-in separator according to claim 1 or claim 2, wherein one of the pair of terminals of the series circuit is connected to an AC line or a DC line, and the other The terminal is connected to a ground point or a neutral wire.

  The invention according to claim 4 is provided with a plurality of SPDs with built-in separator according to claim 3, and the one terminal of each SPD is connected to a different line among a plurality of AC lines or DC lines, respectively. And

According to the present invention, it is possible to reliably detect the mechanical operation of the overcurrent separator or the heat separator and perform failure display and alarm contact output.
In particular, compared to the prior art described in Patent Document 1, it is not necessary to connect an external overcurrent separator, and it is possible to connect to a power source having a large short-circuit current by a single SPD with a built-in separator.

It is a principle block diagram of SPD with a built-in separator according to the first embodiment of the present invention. It is a block diagram which shows the arrangement structure of each part at the time of normal of separator built-in type SPD which concerns on 1st Embodiment of this invention. It is a block diagram of the principal part in FIG. FIG. 3 is an explanatory diagram when an overcurrent separator (current fuse) operates in FIG. 2. It is explanatory drawing when the heat separator (conductor) operates in FIG. It is a fundamental lineblock diagram of SPD with a built-in separator concerning a 2nd embodiment of the present invention. It is a block diagram which shows the prior art of separator built-in type SPD. 1 is a schematic circuit configuration diagram of a direct lightning SPD described in Patent Document 1. FIG. It is operation | movement explanatory drawing of SPD for direct lightning thunder described in patent document 1. FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
First, FIG. 1 is a principle configuration diagram of a separator built-in type SPD according to the first embodiment of the present invention. In FIG. 1, the SPD 1 includes a series circuit of an overcurrent separator 2, a heat separator 3, and a varistor 4 connected between a pair of terminals 11 and 12. Here, the terminals 11 and 12 are respectively connected to an external AC line or a line of a DC line and a grounding point or a neutral line.

  The overcurrent separator 2 is a current fuse that is blown by an overcurrent such as a short-circuit current, and has a function of striking an adjacent member by projecting a striker (bar-shaped member) to the outside when the fuse is blown. The heat separator 3 is a conductor that separates by melting the electrical connection (solder) between the terminals due to heat generated by the varistor 4. The varistor 4 is a metal oxide varistor such as a zinc oxide varistor.

In this embodiment, either an overcurrent or a varistor 4 is detected by either one of a mechanical operation that occurs when the overcurrent separator 2 is blown or a mechanical operation that occurs when the heat separator 3 is separated (OR logic 5). The fault display and alarm contact output of SPD1 indicating overheating and the like are operated.
Next, a specific configuration of the SPD 1 will be described with reference to FIGS.

  FIG. 2 is a configuration diagram showing an arrangement structure of each part when the SPD 1 is normal. In FIG. 2, 20 is a current fuse with a built-in striker, 21 is a fuse body, and 22 is a striker that can protrude to the outside when the current fuse 20 is blown. The current fuse 20 is held on the frame 10 by a fuse holder (not shown).

A metal oxide varistor 40 is accommodated inside the frame 10, and one terminal 41 of the conductor 30 is substantially L-shaped when viewed from the front, and one end of a conductor 30 made of a metal plate having spring properties is soldered. It is attached. The other terminal (not shown) of the varistor 40 is connected to a ground point or a neutral wire.
The other end of the conductor 30 is connected to one electrode 21a of the current fuse 20, and the other electrode 21b of the current fuse 20 is connected to an AC line or a DC line.

Between the current fuse 20 and the terminal 41 of the varistor 40, a substantially L-shaped first slider 23 and a second slider 31 are juxtaposed when viewed from the front.
The first slider 23 has a first receiving portion 26 and a second receiving portion 25 that are projected from a plastic base piece 24, and an operation convex portion 27. A locking projection 24a that locks into the locking recess 55a of the display unit 55 for failure display is provided. In addition, the force which moves to the right direction of FIG. 2 by the spring (not shown) is always acting on the display part 55. FIG.

  The slider 23 can be moved downward as shown in FIG. 2 by striking the first receiving portion 26 with the striker 22 of the current fuse 20, and the operation convex portion 27 is a rotation lever described later when moving downward. 50 is provided. A part of the base piece 24 is formed in a U-shaped cross section, and a first spring 29 described later is accommodated in the internal space.

The second slider 31 is formed in an approximately I shape when viewed from the front, and a part of the second slider 31 is formed in a U-shaped cross section, and a second spring 32 described later is accommodated in the internal space. The slider 31 is urged so as to move downward by the restoring force of the spring 32, but the locking groove 31a formed in the upper end portion is normally engaged with the locking claw 30a inside the conductor 30. This stops the movement downward.
When the locking claw 30a is disengaged from the locking groove 31a, the slider 31 is moved downward by the restoring force of the spring 32, and the lower end thereof presses the second receiving portion 25 of the first slider 23 to slide the slider. 23 has a function of moving downward.

  A rotation lever 50 is arranged below the operation convex portion 27 of the first slider 23, and the rotation lever 50 rotates when the tip of the receiving arm 51 is pressed by the operation convex portion 27. Yes. The rotation lever 50 includes a switch operation piece 52 at the right end, and the switch operation piece 52 presses the actuator 54 of the micro switch 53 to generate an alarm contact output at the time of rotation.

Next, a mechanism for driving the first slider 23 and the second slider 31 will be further described with reference to FIG.
The first spring 29 described above is disposed in the internal space of the base piece 24 of the first slider 23. An upper end portion of the spring 29 is in contact with a stopper 24 b formed integrally with the back side of the base piece 24, and a lower end portion of the spring 29 is in contact with a stopper 10 a formed integrally with the frame 10.
The second spring 32 described above is disposed in the internal space of the second slider 31. The upper end of the spring 32 is in contact with a stopper 10 b formed integrally with the frame 10, and the lower end of the spring 32 is in contact with a stopper 31 b at the bottom of the slider 31.
Appropriate guide members are provided integrally with the frame 10 on both sides of the sliders 23 and 31 so as to make the movement in the vertical direction smooth, but these guide members are not included in the drawing. Is omitted.

As described above, since the lower end of the spring 29 is restrained by the stopper 10a and the upper end of the spring 29 is in contact with the stopper 24b of the slider 23, a restoring force in the direction of moving the slider 23 upward is accumulated. Is done.
On the other hand, in the state of FIG. 3 in which the locking claw 30a of the conductor 30 is locked in the locking groove 31a of the slider 31, the upper end is restrained by the stopper 10b and the lower end is in contact with the stopper 31b of the slider 31. In the spring 32, the restoring force in the direction of moving the second slider 31 downward is accumulated.

Next, the operation of the first embodiment will be described with reference to FIGS.
FIG. 4 is an operation explanatory diagram in a state where the current fuse 20 is blown by an overcurrent and the striker 22 protrudes downward.
In this case, as described above, when the striker 22 strikes the receiving portion 26, the first slider 23 moves downward while contracting the spring 29. Thereby, since the latching convex part 24a remove | deviates from the latching recessed part 55a, the display part 55 moves to the right side with a spring force. Therefore, if an operation display mark is attached to an appropriate position of the display unit 55, for example, the upper surface of FIG. 4, it is possible to confirm that the SPD 1 has been operated (a failure has occurred) by looking at the operation display mark from the outside. It is.

Further, when the slider 23 moves downward, the rotation lever 50 rotates and the micro switch 53 is turned on, so that an alarm contact output can be generated outside.
In the state of FIG. 4, a force to move upward is exerted on the slider 23 by the restoring force of the spring 29.

Next, FIG. 5 is an operation explanatory diagram in a state where the solder that electrically connected the terminal 41 and one end of the conductor 30 is melted due to overheating of the varistor 40 and the conductor 30 is separated from the terminal 41. .
In this case, the conductor 30 is separated from the terminal 41 so as to move in the front direction of the figure due to its springiness. As a result, the locking claw 30a of the conductor 30 is disengaged from the locking groove 31a of the second slider 31, so that the slider 31 moves downward by the restoring force of the spring 32 described above, and the lower end of the slider 31 is the receiving portion. 25, and thus the entire first slider 23 is pressed downward.
The subsequent operation is the same as that in FIG. 4, and the failure display by the display unit 55 and the alarm contact output by the micro switch 53 can be performed.

Next, FIG. 6 is a principle configuration diagram of a separator built-in type SPD according to the second embodiment of the present invention.
As described in the first embodiment, the present invention is used by connecting between one line of an AC line or a DC line and a ground point G or a neutral line, and the AC line or the DC line is composed of two lines, three lines, Even in the case of four wires, the same principle as in the first embodiment can be applied.

  The second embodiment of FIG. 6 is for the case where the separator built-in type SPD 1A is used by being connected between a two-wire AC line or DC line 151, 152 and a ground point G. In FIG. 6, 2A and 2B are overcurrent separators composed of current fuses built in strikers, 3A and 3B are thermal separators such as metal conductors having a spring property, 4A and 4B are metal oxide varistors, and 5A and 5B are OR logics. , 6 are failure display circuits, and 11A, 11B, and 12 are terminals.

In the second embodiment, the unit including the overcurrent separator 2A, the heat separator 3A, and the varistor 4A and the unit including the overcurrent separator 2B, the heat separator 3B, and the varistor 4B are described above. By adopting the configuration of 2, OR logic 5A and 5B of the mechanical operation of the overcurrent separator and the mechanical operation of the heat separator can be realized.
Although the failure display circuit 6 is not essential, for example, by using an LED or the like, it is possible to display the failure by a method such as turning on the LED in normal times and turning it off at the time of failure.

1,1A: SPD with built-in separator
2, 2A, 2B: Overcurrent separators 3, 3A, 3B: Thermal separators 4, 4A, 4B, 40: Varistors 5, 5A, 5B: OR logic 6: Fault display circuit 10: Frames 10a, 10b: Stopper 11 11A, 11B, 12: Terminal 20: Current fuse built in striker 21: Fuse body 22: Striker 23: First slider 24: Base piece 24a: Locking projection 24b: Stopper 25: Second receiving portion 26: First receiving portion 27: operation convex portion 29: first spring 30: conductor 30a: locking claw 31: second slider 31a: locking groove 31b: stopper 32: second spring 40: metal oxide varistor 41 : Terminal 50: Rotating lever 51: Receiving arm 52: Switch operating piece 53: Micro switch 54: Actuator 55: Display portion 55a: Locking recess 151, 152: AC Road or a direct current line G: ground point

Claims (4)

A series fuse consisting of a current fuse as an overcurrent separator in which a striker projects to the outside when the fuse body melts due to overcurrent, a conductor as a heat separator that separates from the terminal of the varistor when the varistor overheats, and the varistor. With a circuit,
In the SPD with a built-in separator that detects a failure based on the mechanical operation of the overcurrent separator or the mechanical operation of the thermal separator,
A first slider that is struck by the striker protruding outward and moves in a certain direction while resisting the restoring force of the first spring;
A switch for alarm contact output that is turned on by the movement of the first slider in the fixed direction;
A second slider that is unlocked when the conductor is separated and moves in the fixed direction by a restoring force of a second spring, and moves the first slider in the fixed direction;
A separator built-in type SPD characterized by comprising: In the SPD with a built-in separator according to claim 1,
A separator-incorporated SPD further comprising a display unit for operation display that is movable when the first slider is unlocked from the first slider by moving in the predetermined direction. . In the SPD with a built-in separator according to claim 1 or claim 2,
One of the pair of terminals of the series circuit is connected to an AC line or a DC line, and the other terminal is connected to a ground point or a neutral line.   A separator built-in type SPD comprising a plurality of built-in separator type SPDs according to claim 3, wherein the one terminal of each SPD is connected to a different line among a plurality of AC lines or DC lines.

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