JP2014191908A - Leakage detection tripping unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a leakage detection tripping unit capable of suppressing temperature rise in the vicinity of a connection terminal part of a circuit breaker.SOLUTION: A leakage detection tripping unit 4 externally attached to a circuit breaker includes a main circuit bar serving as an electric circuit. On one end side of this main circuit bar, a connection end terminal part 7a is provided which is a connection portion with respect to the connection terminal part of the circuit breaker. A heat transfer member 14 formed in an approximately L-shape is provided from the connection terminal part 7a of the main circuit bar protected by a terminal cover 10 over the side surface on the side close to a mechanical part 13 of a housing body 11. This heat transfer member 14 moves heat generated in the connection terminal part 7a.

Description

  The present invention relates to a leakage detection trip unit applied to an external trip type earth leakage breaker and attached to a circuit breaker.

  Conventionally, an earth leakage circuit breaker that interrupts an electric circuit when an earth leakage is detected has been proposed (see, for example, Patent Document 1). There are two types of earth leakage circuit breakers: one with a leakage detection function added to the inside of the circuit breaker, and one with a built-in leakage detection function in a device externally connected to the circuit breaker, which is connected to the circuit breaker. . The latter is called an external trip type earth leakage breaker, and the device externally attached to the circuit breaker is called an earth leakage detection trip unit.

  In general, a circuit breaker is provided with a power terminal portion on one end side and a load terminal portion on the other end side, and the contact portion, the trip mechanism portion, and the contact portion are turned on and off between both terminal portions. A handle mechanism. In addition, there is one having a grid portion that extinguishes an arc generated when the contact portion is tripped by the trip mechanism. On the other hand, the leakage detection trip unit is provided with a connection terminal part on one end side and a load terminal part on the other end side. Between the two terminal parts, a leakage detection circuit, a main circuit bar serving as an electric circuit, and leakage detection A tripping drive unit that acts on the tripping mechanism unit of the circuit breaker by a signal. In the external trip type earth leakage breaker, the connection terminal portion of the leakage detection trip unit is connected to the load terminal portion of the circuit breaker (hereinafter referred to as the connection terminal portion of the circuit breaker).

  A zero phase current transformer is used to detect a leakage by the leakage detection trip unit, and a main circuit bar is passed through the ZCT. For example, in the case of three-phase four-wire, four main circuit bars are passed through the ZCT. At the time of energization, the difference between the current in the forward path and the return path passing through the ZCT is detected. When there is no leakage, the difference is zero, but when a leakage occurs, a difference occurs in the current between the forward path and the return path, and the difference is amplified to block the circuit. The main circuit bar replaces the wires, and one end of the main circuit bar is fixed to the connection terminal of the circuit breaker with a terminal screw, and the other end is connected to the load terminal of the leakage detection trip unit via the terminal plate The terminal is fixed with terminal screws.

JP 2011-124217 A

  In the external trip type earth leakage breaker, the temperature rise of the connection terminal part of the circuit breaker when energized is larger than that when only the circuit breaker is energized. The temperature rise tends to increase.

  The present invention has been made paying attention to such problems, and an object thereof is to provide a leakage detection trip unit capable of suppressing a temperature rise in the vicinity of a connection terminal portion of a circuit breaker. There is.

  The earth leakage detection trip unit that solves the above problems is provided with a power terminal portion on one end side and a connection terminal portion on the other end side that is the load side, and a contact portion and a trip mechanism portion between both terminal portions. And a circuit breaker having a handle mechanism portion for turning on and off the contact portion, a connection terminal portion which is a connection portion to the connection terminal portion of the circuit breaker on one end side, and a load terminal on the other end side Each of which is provided with a leakage detection circuit, a main circuit bar serving as an electric circuit, and a tripping drive unit that acts on the tripping mechanism of the circuit breaker by a leakage detection signal. A leakage detection trip unit applied to an external trip type earth leakage breaker configured in combination with an earth leakage detection trip unit and connected to the circuit breaker, and a connection terminal portion of the earth leakage detection trip unit The heat generated in And the as its gist further comprising a heat transfer member for.

About the said earth-leakage detection trip unit, it is good also as having provided the said heat-transfer member along the electric circuit by the said main circuit bar.
With respect to the leakage detection trip unit, the heat transfer member may be made of a material having a higher thermal conductivity than the material of the casing of the leakage detection trip unit.

About the said earth-leakage detection trip unit, the said heat-transfer member is good also as contacting the inner surface of the housing | casing of the said earth-leakage detection trip unit.
About the said earth-leakage detection trip unit, the said heat-transfer member is good also as having a 1 or several protrusion part in the surface which comprises a heat-transfer path | route.

  With respect to the leakage detection trip unit, vents are provided on the surface including the load terminal portion of the casing of the leakage detection trip unit and the surface opposite to the surface, and the protrusion is provided on a line connecting both the ventilation ports. It may be arranged.

  For the leakage detection trip unit, between the vent and the zero layer current transformer which is a component of the leakage detection circuit, between the vent and the projection provided on the load terminal side of the housing It is good also as having the 2nd projection part which narrows the channel which goes to.

  ADVANTAGE OF THE INVENTION According to this invention, the temperature rise near the connection terminal part of a circuit breaker can be suppressed.

The front view which shows the external trip type earth-leakage circuit breaker to which the earth-leakage detection trip unit in 1st Embodiment was applied. The front view of an external trip type earth leakage breaker excluding the cover of the earth leakage detection trip unit. The perspective view of a leak detection trip unit. The perspective view of the earth-leakage detection trip unit except a heat-transfer member. The perspective view of the earth-leakage detection trip unit except a cover about 2nd Embodiment. The disassembled perspective view which similarly shows the heat-transfer member in a housing | casing. The perspective view of the earth-leakage detection trip unit except a cover about 3rd Embodiment. The disassembled perspective view which shows the heat-transfer member in a housing | casing with a protrusion similarly. The bottom view of a leak detection trip unit. Top view of the leakage detection trip unit. Sectional drawing of a leak detection trip unit.

(First embodiment)
Hereinafter, a first embodiment of the leakage detection trip unit will be described.
As shown in FIG. 1, the external trip type earth leakage breaker is roughly composed of a circuit breaker 3 and an earth leakage detection trip unit 4. In this earth leakage circuit breaker, the electric wire 1 is fixed by the terminal screw 2 in the power terminal part 3 a of the circuit breaker 3 and the load terminal part 4 a of the earth leakage detection trip unit 4. The plurality of circuit breakers 3 are connected by a connecting handle 5. This connection handle 5 is connected to the interlocking handle 6 of the leakage detection trip unit 4 and is interlocked by the interlocking handle 6 that operates when the leakage is detected, thereby interrupting the circuit.

  As shown in FIG. 2, the main circuit bar 7 serving as an electric circuit is routed inside the leakage detection trip unit 4, and the tip of the main circuit bar 7 is welded to the terminal plate 8. All four main circuit bars 7 pass through the ZCT 9.

  As shown in FIG. 3, the leakage detection trip unit 4 includes a main circuit bar 7, a terminal cover 10, a housing body 11, a housing cover 12, a mechanical unit 13, and a heat transfer member 14. Is done. The main circuit bar 7 has a connection terminal portion 7a on one end side fixed to a connection terminal portion 3b (see FIG. 1) of the circuit breaker 3 with a terminal screw 2, and the other end side is connected to a leakage detection trip unit via a terminal plate 8. 4 is fixed to the load terminal portion 4a with the terminal screw 2.

  As shown in FIG. 4, the heat transfer member 14 is substantially L-shaped from the connection terminal portion 7 a of the main circuit bar 7 protected by the terminal cover 10 to the side surface 11 a near the mechanical portion 13 of the housing body 11. Is formed. The heat transfer member 14 is made of a material (for example, aluminum) having a higher thermal conductivity than the material (for example, synthetic resin) of the casing formed by the terminal cover 10, the casing body 11, and the casing cover 12. The heat transfer member 14 is provided along the electric circuit by the main circuit bar 7, and the heat transfer member 14 generates heat on the surfaces 10 a, 11 a, 12 a, and 13 a (shaded portions in FIG. 4) near the circuit breaker 3. Is easy to move.

Next, the operation of the leakage detection trip unit 4 will be described.
The heat generated at the connection terminal portion 7 a of the main circuit bar 7 with the energization is diffused by the heat transfer member 14. At this time, heat easily moves from the connection terminal portion 7a of the main circuit bar 7 toward the side surface 11a on the side close to the mechanical portion 13 of the housing body 11 having a lower temperature. Further, the heat transfer member 14 also absorbs and diffuses the heat of the electric circuit other than the connection terminal portion 7a. Moreover, since the heat transfer member 14 is derived from aluminum and has high thermal conductivity, heat easily moves. Therefore, even when the temperature rise value of the connection terminal portion 7a becomes high, the temperature rise value can be reduced by heat transfer.

As described above, according to the first embodiment, the following effects can be obtained.
(1) Since the heat generated in the connection terminal portion 7a of the leakage detection trip unit 4 is diffused by the heat transfer member 14, a temperature increase in the vicinity of the connection terminal portion 3b of the circuit breaker 3 can be suppressed.

(2) The heat transfer member 14 also absorbs and diffuses heat from the electric circuit other than the connection terminal portion 7a, so that the temperature rise near the connection terminal portion 3b is further reduced.
(3) Since the heat transfer member 14 has higher thermal conductivity than the housing material, more effective thermal diffusion can be obtained.

  (4) With the temperature rise in the vicinity of the connection terminal portion 3b of the circuit breaker 3 being suppressed, there is no need to separately attach a cover that covers the connection terminal portion 3b. That is, it is not necessary to lower the surface temperature with the lid.

(Second Embodiment)
Next, a second embodiment of the leakage detection trip unit will be described.
As shown in FIG. 5, the leakage detection trip unit 4 in the present embodiment includes an in-casing heat transfer member 15. In addition, since it is the same as that of the said 1st Embodiment except the point provided with the heat transfer member 15 in a housing | casing, the same code | symbol is attached | subjected to a common component and the description is abbreviate | omitted. .

  As shown in FIG. 6, the in-housing heat transfer member 15 is formed in a substantially U shape and is in contact with the inner side surface of the housing body 11. Similarly to the heat transfer member 14, the in-case heat transfer member 15 is made of a material (for example, aluminum) having a higher thermal conductivity than the material of the case. Note that the same material as the material of the heat transfer member 14 or a different material may be used. The in-casing heat transfer member 15 can easily transfer the heat transferred from the connection terminal portion 7 a by the heat transfer member 14 to the inside of the casing body 11.

Next, the operation of the leakage detection trip unit 4 will be described.
The heat transferred from the connection terminal portion 7 a by the heat transfer member 14 is transferred to the in-housing heat transfer member 15 through the wall of the housing body 11 interposed between the in-housing heat transfer member 15. The heat transmitted to the in-casing heat transfer member 15 is diffused inside the casing having a lower temperature. Moreover, since the heat transfer member 15 in a housing | casing originates in aluminum and has high heat conductivity, heat | fever moves easily. Therefore, even when the temperature rise value of the connection terminal portion 7a becomes high, the temperature rise value can be reduced by heat transfer.

As described above, according to the second embodiment, in addition to the same effects as the effects (1) to (4) according to the first embodiment, the following effects can be achieved.
(5) Since the in-casing heat transfer member 15 is in contact with the inner surface of the casing, heat is likely to diffuse inside the casing at a lower temperature.

(Third embodiment)
Next, a third embodiment of the leakage detection trip unit will be described.
As shown in FIG. 7, the leakage detection trip unit 4 in the present embodiment includes an in-housing housing heat transfer member 16. In addition, since it is the same as that of the said 1st Embodiment except the point provided with the heat transfer member 16 with a protrusion, the same code | symbol is attached | subjected to the common component and the description is given. Omitted.

  As shown in FIG. 8, the in-housing case heat transfer member 16 has a plurality of protrusions on the surface constituting the heat transfer path, and is in contact with the inner side surface of the case body 11. Similarly to the heat transfer member 14 and the heat transfer member 15 in the case, the heat transfer member 16 in the case with protrusions is also made of a material (for example, aluminum) having a higher thermal conductivity than the material of the case. In addition, the same material as the material of the heat transfer member 14 or the heat transfer member 15 in a housing | casing may be sufficient, and a different material may be sufficient. The in-case heat transfer member 16 with protrusions easily transfers the heat transferred from the connection terminal portion 7 a by the heat transfer member 14 to the inside of the case body 11. Moreover, since the heat transfer member 16 with a protrusion in a housing | casing has a projection part, it is easy to radiate heat.

  As shown in FIG. 9, the surface 11b of the housing body 11 in the vicinity of the load terminal portion 4a is formed with a vent hole 17 having a hole formed by combining a circle and a rectangle. On the other hand, on the surface 12 b on the load terminal portion 4 a side of the housing cover 12, a vent hole 18 having a hole having the same shape as the vent hole 17 is formed. Note that when the leakage detection trip unit 4 is installed, the surface 11b on which the vent hole 17 is formed and the surface 12b on which the vent hole 18 is formed are directed to the ground side.

  As shown in FIG. 10, in the case body 11, a vent hole 19 having a hole having the same shape as the vent hole 17 and the vent hole 18 is formed on the surface 11 c opposite to the surface 11 b on which the vent hole 17 is formed. Is formed. The protrusion-in-case heat transfer member 16 is disposed on a line connecting the vent 17 and the vent 19. Through these vent holes 17 to 19, the heat transfer member 16 with projections is ventilated, and heat is released to the outside of the leakage detection trip unit 4.

  As shown in FIG. 11, in the housing cover 12, a second projection 20 is formed between the vent 18 and the ZCT 9 to narrow the flow path from the vent 18 to the in-housing housing heat transfer member 16. Has been.

Next, the operation of the leakage detection trip unit 4 will be described.
The heat transferred from the connection terminal portion 7 a by the heat transfer member 14 is transferred to the in-projection case heat transfer member 16 through the wall of the case body 11 interposed between the heat transfer member 16 in the case with protrusions. . The heat transferred to the in-housing case heat transfer member 16 is diffused inside the case having a lower temperature. Moreover, since the heat transfer member 15 in a housing | casing originates in aluminum and has high heat conductivity, heat | fever moves easily. At this time, the heat transfer member 16 in the housing with protrusions has a large surface area due to the protrusions, and therefore easily dissipates heat. The heat released from the projection-internal housing heat transfer member 16 is released to the outside of the leakage detection trip unit 4 together with the airflow passing through the vent holes 17 to 19. In addition, since the flow path area is narrowed by the second protrusion 20, an air flow having a higher flow velocity hits the heat transfer member 16 in the housing with protrusions, and thus heat release to the outside is enhanced. Therefore, even when the temperature rise value of the connection terminal portion 7a becomes high, the temperature rise value can be reduced by heat transfer.

As described above, according to the third embodiment, in addition to the same effects as the effects (1) to (4) according to the first embodiment, the following effects can be achieved.
(6) Since the heat transfer member 16 in the housing with protrusions is in contact with the inner surface of the housing, heat is likely to diffuse inside the housing at a lower temperature.

(7) Since there are a plurality of projections on the heat transfer member 16 in the housing with protrusions, the heat radiation effect to the inside of the housing is high and heat is easily diffused.
(8) Since the protrusions of the heat transfer member 16 in the housing with protrusions are cooled by the airflow passing through the vents 17 and 19, the heat is released together with the airflow to the outside of the leakage detection trip unit 4. The increase value can be reduced. Moreover, a larger surface area can be ensured because the protrusions of the heat transfer member 16 in the case with protrusions are inside the case.

  (9) Since the flow path area is narrowed by the second protrusion 20, an air flow having a higher flow velocity comes into contact with the protrusion of the heat transfer member 16 in the housing with protrusion, and thus the heat dissipation of the protrusion is improved. Thus, a more effective temperature rise value can be expected.

Each of the above embodiments can be modified and embodied as follows.
-In common with each embodiment, the material of the heat-transfer member 14 is not limited to aluminum. It is desirable to use a material having a higher thermal conductivity than the housing material.

-About 2nd Embodiment, the material of the heat-transfer member 15 in a housing | casing is not limited to aluminum. It is desirable to use a material having a higher thermal conductivity than the housing material.
-About 3rd Embodiment, the material of the heat transfer member 16 in a housing | casing with a protrusion is not limited to aluminum. It is desirable to use a material having a higher thermal conductivity than the housing material.

  In common with each embodiment, the shape of the heat transfer member 14 can obtain high efficiency in absorbing and diffusing the heat of the electric circuit according to the routing of the main circuit bar 7 serving as the electric circuit. Is desirable.

-About 3rd Embodiment, the number of the projection parts of the heat-transfer member 16 with a protrusion in a housing | casing is not restricted to plural, One may be sufficient. In addition, the heat dissipation effect increases as the number of protrusions increases.
-Regarding the third embodiment, the shape, size, number, position, etc. of the vents 17 to 19 are arbitrarily determined in consideration of the cooling ability by the airflow passing through them and the ease of processing during manufacturing. It can be set.

-About 3rd Embodiment, the shape of the 2nd projection part 20, a position, an angle, a number, etc. can be arbitrarily set according to the flow velocity, flow volume, etc. which are calculated | required by airflow.
The thickness of the heat transfer member 14, the heat transfer member 15 in the housing, and the heat transfer member 16 in the housing with protrusions can be arbitrarily set according to the required heat transfer capability.

  In common with each embodiment, the material of the terminal cover 10, the housing body 11, and the housing cover 12 is a material in which the heat generated in the connection terminal portion 7a can easily move through the heat transfer member 14, etc. A material that promotes heat transfer by the heat transfer member 14 or the like is desirable. It is desirable that heat transfer by the heat transfer member 14 and the like is promoted not only by the material but also by the wall thickness, the contact area with the heat transfer member 14 and the like.

  DESCRIPTION OF SYMBOLS 1 ... Electric wire, 2 ... Terminal screw, 3 ... Circuit breaker, 3a ... Power supply terminal part, 3b ... Connection terminal part, 4 ... Leakage detection trip unit, 4a ... Load terminal part, 5 ... Connection handle (handle mechanism part) , 6 ... Interlock handle (trip driving unit), 7 ... Main circuit bar, 7a ... Connection terminal, 8 ... Terminal plate, 9 ... ZCT (leakage detection circuit), 10 ... Terminal cover (housing), 10a ... surface 11 ... Case body (housing), 11a ... Side, 11b ... Side, 11c ... Side, 12 ... Case cover (housing), 12a ... Side, 12b ... Side, 13 ... Mechanical part, 13a ... Side, 14 ... Heat transfer member (heat transfer member), 15 ... Heat transfer member in housing (heat transfer member), 16 ... Heat transfer member in housing with projection (heat transfer member), 17 ... Vent, 18 ... Vent, 19 ... vent hole, 20 ... second protrusion.

Claims (7)

A power supply terminal part is provided on one end side, and a connection terminal part is provided on the other end side that is the load side, and a contact part, a trip mechanism part, and a handle for turning on and off the contact part between both terminal parts. A circuit breaker provided with a mechanism part, a connection terminal part which is a connection part to the connection terminal part of the circuit breaker on one end side, and a load terminal part on the other end side, respectively, between both terminal parts, An earth leakage detection circuit, a main circuit bar serving as an electric circuit, and an earth leakage detection trip unit including a trip driving unit that acts on the trip mechanism of the circuit breaker by the earth leakage detection signal are combined. In the earth leakage detection trip unit applied to the external trip type earth leakage breaker and attached to the circuit breaker,
An earth leakage detection trip unit comprising a heat transfer member that moves heat generated at a connection terminal portion of the earth leakage detection trip unit. The electric leakage detection trip unit according to claim 1, wherein the heat transfer member is provided along an electric path by the main circuit bar. The leakage detection trip unit according to claim 1 or 2, wherein the heat transfer member is made of a material having a higher thermal conductivity than a material of a housing of the leakage detection trip unit. The leakage detection trip unit according to any one of claims 1 to 3, wherein the heat transfer member is in contact with an inner surface of a casing of the leakage detection trip unit. The leakage detection trip unit according to any one of claims 1 to 4, wherein the heat transfer member has one or a plurality of protrusions on a surface constituting a heat transfer path. 6. The surface of the casing of the leakage detection trip unit including the load terminal portion and a surface facing the surface, respectively, are provided with vents, and the protrusion is disposed on a line connecting both vents. Earth leakage detection trip unit. A second channel that narrows a flow path from the vent to the protrusion between a vent provided on the load terminal side of the housing and a zero-layer current transformer that is a component of the leakage detection circuit; The leakage detection trip unit according to claim 6.