JP4769275B2 - Earth leakage relay - Google Patents

Description

The present invention relates to a leakage relay that cuts off a connection between a power source and a load when a ground fault current flows.

Conventionally, various earth leakage relays that disconnect a connection between a power source and a load when a ground fault current flows are provided.

As shown in FIG. 7, the leakage relay described in Patent Document 1 as an example thereof includes a connection unit 51 that connects a power source and a load, a detection unit 52 that detects a ground fault current, and a detection unit. In accordance with the detection result of 52, a blocking mechanism 53 for blocking the connection of the connecting portion 51 and a case 54 for housing the blocking mechanism 53 are provided.

The connecting portion 51 includes a pair of fixed terminal portions 55 each having a fixed contact 55 a at an end thereof, and a fixed contact 55.
a pair of movable springs 56 having a movable contact 56a at one end facing a.
The other end of the movable spring portion 56 is fixed to the detection portion 52, and can be swung around the other end portion as a fulcrum. The shut-off mechanism 53 includes an electromagnetic solenoid 57, an operation unit 58, a spring 59, and a latch unit 60. The electromagnetic solenoid 57 includes a solenoid 57a and a plunger (not shown) disposed in the solenoid 57a by being elastically biased by a spring body (not shown). The operation portion 58 is formed in a substantially rectangular tube shape having an open bottom surface, and a spring 59 is inserted through the opening. The latch portion 60 includes a support rod 60a formed in a rod shape and a main body 60b formed in a square tube shape. Furthermore, the main body 60b is formed with a slit 60c that is recessed inward. The case 54 is formed in a substantially box shape with a lower surface opened, and a cover 54a provided with a penetrating portion 61 penetrating the upper wall portion, and a body 54 with an upper surface opened and formed in a substantially box shape.
b is formed by fitting. The electromagnetic solenoid 57 and the fixed terminal portion 55 are mounted on a rectangular printed wiring board 62 having a penetrating portion 62a penetrating in the thickness direction.

The operation portion 58 protrudes upward from the upper wall portion of the cover 54a through the through portion 61 and is hooked on the latch portion 60 against the elastic bias of the spring 59 in the case 54. Match. The tip of the plunger is inserted into the slit 60c and presses the main body 60b. At this time, the support bar 60a pushes up the movable spring portion 56 from below, so that the movable contact 56a contacts the fixed contact 55a, and the power source and the load are connected.

When the ground fault current is detected by the detection unit 52 composed of a zero-phase current transformer, the solenoid 57a is energized by the output of the detection unit 52, and the plunger is attracted in a direction orthogonal to the operation direction of the operation unit 58. To be moved. Then, the engagement between the operation unit 58 and the latch unit 60 is released,
The operation portion 58 moves upward by the elastic return force of the spring 59, and the latch portion 60 is moved to the movable spring portion 56.
It moves downward due to the elastic return force. That is, the movable contact 56a is separated from the fixed contact 55a, and the connection between the power source and the load is interrupted.
JP 2002-25417 A

However, the breaking mechanism 53 for moving the movable contact 56a of the conventional earth leakage relay to and from the fixed contact 55a has a problem that its structure is complicated and assembly workability is poor.

The present invention has been made in view of the above-mentioned reasons, and an object thereof is to provide a leakage relay capable of reducing the number of parts and simplifying the structure and improving the assembly workability as compared with the prior art. is there.

In order to achieve the above object, the first aspect of the present invention provides a connection unit that connects a power source and a load, a detection unit that detects a ground fault current, and the connection unit according to a detection result of the detection unit. And a case that is formed in a box shape and accommodates the blocking mechanism, the connecting portion having a fixed terminal portion having a fixed contact at an end portion, and one end facing the fixed contact. And a movable spring portion having a movable contact at a fixed other end, and the breaking mechanism is disposed in a solenoid that is energized by detection of a ground fault current and the solenoid. An electromagnetic solenoid having a plunger, a position where the movable contact contacts the fixed contact against an elastic return force of the movable spring portion, and a position where the movable contact is separated from the fixed contact by the elastic return force Freely movable between The latch portion is disposed at a position facing the movable spring portion and is in contact with the movable spring portion, and at least when the latch portion is in the separated position, An operation portion that protrudes to the outside of the case through a penetrating portion that penetrates the case is provided, and a distal end portion of the plunger is detachably engaged with a wall surface of the latch portion facing the distal end portion of the plunger. The movable spring portion is formed to be bent in a substantially U shape, and the contact portion of the latch portion is in pressure contact with the top portion of the movable spring portion. It is characterized by.

According to the present invention, the shut-off mechanism includes an electromagnetic solenoid and a latch portion, and the latch portion includes an abutment portion and an operation portion, and a distal end portion of the plunger is engaged and disengaged with the latch portion. Since the recess that freely engages is provided, the number of parts can be reduced and the structure can be simplified as compared with the prior art, and the assembly workability can be improved. Moreover, since the contact part of a latch part press-contacts with respect to the top part of a movable spring part, the area which contacts can be small and contact reliability can be made high.

The invention of claim 2 is characterized in that, in the invention of claim 1, a guide portion is provided in the case for restricting a moving direction of the latch portion to only the movable direction.

According to the present invention, the guide portion provided in the case can prevent the latch portion from falling off when moving inside the case, and can improve the contact reliability with respect to the movable spring portion.

In the present invention, the number of parts can be reduced and the structure can be simplified as compared with the conventional one, so that the assembling workability can be improved , and the contact portion of the latch portion is in pressure contact with the top portion of the movable spring portion. Therefore, there is an effect that the contact area is small and the contact reliability can be increased .

Hereinafter, embodiments of the present invention will be described with reference to FIGS. In the following description, the vertical and horizontal directions are defined in FIG.

As shown in FIG. 1, the leakage relay of the present embodiment includes a connection portion 1 that connects a power source and a load.
And a detecting unit 2 that detects a ground fault current, a blocking mechanism 3 that blocks connection of the connecting unit 1 according to a detection result of the detecting unit 2, and a case 4 that houses the blocking mechanism 3. And the case 4 which accommodated these is fixed on the rectangular printed wiring board 5 by screwing. The printed wiring board 5 of the present embodiment has a copper foil wiring pattern on the lower surface, and has three insertion holes 5a (see FIG. 5) penetrating through the front center portion and the left and right ends of the substantially center portion in the front-rear direction. 1, only one is shown), and a screw 29 protrudes upward through the insertion hole 5a.

As shown in FIGS. 1 and 3, the connecting portion 1 includes a pair of fixed terminal portions 6 and a pair of movable spring portions 7.
It consists of. The fixed terminal portion 6 is formed by bending a rectangular plate at a substantially central portion in the longitudinal direction, and a round fixed contact 6a protruding upward is caulked and fixed on the upper surface of the rear end portion. A pair of engaging pieces 6b that protrude upward are provided on the left and right ends of the rear part. The movable spring portion 7 bends the elongated rectangular plate closer to the front than the substantially central portion in the longitudinal direction, and the bent portion is the top portion 7.
It is formed in the shape of an abbreviated letter c. A front end portion of the movable spring portion 7 is bent forward, and a round movable contact 7a protruding downward is fixed by crimping at a position facing the fixed contact 6a on the lower surface of the front end portion. The rear end portion of the movable spring portion 7 is bent rearward, and a pair of engagement pieces 7d protruding upward are provided on the left and right end portions, respectively, and the outermost end of the rear end portion is further bent downward. Thus, a terminal piece 7b is formed. The movable spring portion 7 and the case 4 are engaged by press-fitting the engagement piece 7d into an engagement groove 34 of the case 4 described later. Further, the case 4 is attached to the printed wiring board 5.
When being mounted on the top, the terminal strip 7 b is inserted into an elongated rectangular groove (not shown) penetrating the printed wiring board 5 and then soldered to the printed wiring board 5. In other words, the movable spring portion 7 has a front end portion that can swing in the vertical direction with the rear end portion as a fulcrum. Note that the front end portion of the fixed terminal portion 6 is connected to a circuit on the power source side.

As shown in FIGS. 1 and 2, the detector 2 includes a zero-phase current transformer 9 formed in a substantially donut shape that detects a ground fault current. Two jumper wires 13 are inserted through the central portion of the zero-phase current transformer 9, and one end portion of the jumper wire 13 is connected to the movable spring portion 7 via the wiring pattern on the lower surface of the printed wiring board 5. The other end is connected to the output connector 8. If the zero-phase current transformer 9 detects a ground fault current, the solenoid 22 is energized. In addition, a surge absorber 10 for protecting the circuit from a surge voltage, a fuse 11 and a fuse holder 12, an electrolytic capacitor 14, and other circuit components 15 are provided and mounted on the printed wiring board 5 by soldering. The rear end portion of the movable spring portion 7 is connected to a circuit on the load side via the jumper wire 13 and the output connector 8.

As shown in FIG. 1, the blocking mechanism 3 includes an electromagnetic solenoid 20 and a latch portion 21. The electromagnetic solenoid 20 includes a solenoid 22 formed in a substantially cylindrical shape as a whole and a plunger 23 formed in an elongated cylindrical shape disposed inside the solenoid. The solenoid 22 includes a body 22a formed in a cylindrical shape and having a coil wound around an outer peripheral surface thereof, and a yoke 22b formed in a substantially U-shape covering the front and rear wall portions and the upper portion of the body 22a. Body 2
The central axis of 2a is provided with a plunger hole (not shown) that opens in a cylindrical shape from the front surface of the body 22a and the yoke 22b to the rear. The plunger 23 is inserted into the plunger hole together with a spring body 24 shown in FIG. 5 and a locking piece 25 formed in a disk shape having a projection 25a fitted to the spring body 24 on the front surface. . As shown in FIG. 5, the latch portion 21 is formed in a substantially cross shape as a whole, and has a rectangular tube-shaped latch portion main body 21 a extending in the vertical direction, and left and right from a substantially central portion in the vertical direction of the latch portion main body 21 a. It consists of a pair of contact part 21b extended in the direction. Further, the upper end portion of the latch portion main body 21a becomes the operation portion 21d. Further, the rear surface of the latch portion main body 21a has a concave portion 21c that is recessed forward in a substantially oval shape.
The tip of the plunger 23 is detachably engaged with the recess 21c.

As shown in FIGS. 1, 2, and 4, the case 4 includes a case main body 26 that is formed in a substantially box shape with an open bottom surface, and a case rear portion 27 that is formed in a substantially semi-circular circular plate shape. Connected in the direction.

As shown in FIG. 4B, the case main body 26 includes a recess 30 that is substantially H-shaped and recessed upward, and a storage portion 31 that is recessed upward in a rectangular shape. . In addition, at the front and rear portions of the lower surface, elongated rectangular engaging grooves 33 and 34 that are recessed upward are arranged in parallel in four directions in the left-right direction. A rectangular penetrating portion 28 penetrating upward is provided at the center of the inner bottom surface of the recess 30. On the inner wall surface of the left and right end portions of the case body 26, guide portions 32 formed in a concave shape in the vertical direction are provided.

As shown in FIG. 4C, the case main body 26 accommodates the blocking mechanism 3, the movable spring portion 7, and the rear portion of the fixed terminal portion 6 therein. The latch portion 21 is configured so that the operation portion 21d faces the penetrating portion 28 and the concave portion 21c faces the storage portion 31 side from the lower surface where the case body 26 opens.
The left and right end portions of the contact portion 21b are fitted into the guide portions 32 and inserted upward. The pair of movable spring portions 7 are fitted in recesses extending in the front-rear direction of the left and right ends of the recess 30 with the movable contact 7a facing forward. At this time, the movable spring portion 7 and the case body 26 are engaged by press-fitting the engaging pieces 7d of the movable spring portion 7 into the engaging grooves 34, respectively. At the same time, the lower surface of the abutting portion 21 b of the latch portion 21 faces and abuts the top portion 7 c of the movable spring portion 7. That is, the engagement between the movable spring portion 7 and the case main body 26 prevents the latch portion 21 from coming off from the lower surface of the case main body 26. The pair of fixed terminal portions 6 and the case main body 26 are engaged with each other by pressing the engagement pieces 6b into the engagement grooves 33 with the fixed contacts 6a facing rearward.

When the latch portion 21 is moved downward along the guide portion 32 against the elastic return force of the movable spring portion 7, the movable contact 7a contacts the fixed contact 6a. Conversely, if the latch portion 21 moves upward along the guide portion 32 due to the elastic return force, the movable contact 7a is separated from the fixed contact 6a. In other words, the latch portion 21 is movable between positions where the movable contact 7a and the fixed contact 6a come into contact with or separate from each other. The front end portion of the case body 26 is provided with a pair of lead-out portions 26a formed by cutting out into a rectangular shape, and the front portion of the fixed terminal portion 6 is connected to the outside of the case body 26 through the lead-out portions 26a. Has been derived. A pair of claw portions 31a having a lower end projecting inwardly extend downward at the front end portion of the periphery of the storage portion 31, and a claw portion 31a is also extended at the rear end portion. Then, the electromagnetic solenoid 20 elastically locks the three claw portions 31a to the front end portion and the rear end portion of the lower surface of the electromagnetic solenoid 20 while the front end portion of the plunger 23 faces the rear surface of the latch portion main body 21a. It is fixed to the storage part 31.

That is, the blocking mechanism 3, the movable spring portion 7, and the fixed terminal portion 6 can be temporarily fixed inside the case body 26 in advance by press-fitting or elastic locking.

The case rear part 27 is formed in a substantially semi-circular circular plate shape as a whole, and a recessed part 27 a that is recessed downward in a semi-oval shape is provided inside the outer peripheral edge of the case rear part 27. Hollow 2
A central plate 27b having a rectangular plate shape protruding upward is disposed at the center of the inner bottom surface of 7a.
A circular hole 27c and an oval long hole 27d are provided in the vicinity of the left and right roots of 7b. In addition, an outlet 27e that penetrates downward in a substantially rectangular shape in front of the inner bottom surface of the recess 27a.
Is provided. The case rear portion 27 has a front right end portion provided with a rectangular tube portion 27f that protrudes outward in a substantially rectangular tube shape, and a circular hole 27g that penetrates the rectangular tube portion 27f in the vertical direction. The rear left end portion of the case rear portion 27 is provided with a cylindrical portion 27h that protrudes outward in a substantially cylindrical shape, and a circular hole 27i that penetrates the cylindrical portion 27h in the vertical direction.

Then, the zero-phase current transformer 9 formed in a substantially donut shape is inserted into the recess 27a from above and placed on the inner bottom surface of the recess 27a. At this time, the center plate 27b is fitted in the central portion where the zero-phase current transformer 9 is opened. An electric wire (not shown) led out from the lower front side of the zero-phase current transformer 9 is connected to the electromagnetic solenoid 20 located forward through a lead-out part 27e.

As means for fixing the case 4 to the printed wiring board 5, as shown in FIG.
6 is provided with a pair of projecting portions 26b projecting in a semi-cylindrical shape outward, and further, a screw hole 26c is formed at the center of the lower surface of the projecting portion 26b. ing. A screw hole 26c is also provided at the center in the left-right direction in front of the lower surface of the case body 26. The insertion holes 5a are inserted into the three screw holes 26c from the lower surface of the printed wiring board 5.
The case 4 is fixed to the printed wiring board 5 by stopping the screw 29 via At this time, the terminal piece 7b of the movable spring portion 7 is soldered to the printed wiring board 5 through a groove (not shown) penetrating the printed wiring board 5 as described above. Two jumper wires 1
3 passes through the center of the donut portion of the zero-phase current transformer 9 and passes through the hole 27c from above the case rear portion 27.
And 27g, the long holes 27d and the holes 27i, are drawn out to the upper surface of the printed wiring board 5, and are soldered to the lower surface of the printed wiring board 5 through through holes (not shown).

The operation of the leakage relay of this embodiment will be described. When the detector 2 does not detect the ground fault current, the plunger 23 is elastically biased forward by the spring body 24 as shown in FIG. 5A, and the tip of the plunger 23 is engaged with the recess 21c. Therefore, the upward movement of the latch portion 21 by the elastic restoring force of the movable spring portion 7 is restricted. Due to the engagement of the plunger 23, the lower surface of the abutting portion 21 b of the latch portion 21 resists the elastic return force of the movable spring portion 7, as shown in FIG. It is pressed down. The movable spring portion 7 is pushed down by elastic deformation with the rear end portion as a fulcrum, and the movable contact 7a is in contact with the fixed contact 6a. That is, the connection unit 1 is in a closed state, and the power source and the load are connected.

If the detection unit 2 detects a ground fault current, the solenoid 22 is first energized to generate the electromagnetic solenoid 2.
0 is excited. And the attraction | suction force which acts to the back with respect to the plunger 23 in a plunger hole (not shown) is generate | occur | produced. With this suction force, the plunger 23 moves rearward while contracting the spring body 24 against the elastic bias of the spring body 24 as shown in FIG. Along with this, the engagement between the distal end portion of the plunger 23 and the concave portion 21 c is released, and the latch portion 21.
The upward movement restriction is released. Then, as shown in FIG.
It is pushed up by the elastic return force of the movable spring portion 7 and moves upward along the guide portion 32, so that the movable contact 7a is separated from the fixed contact 6a. That is, the connection unit 1 is opened, and the connection between the power source and the load is interrupted. At this time, at least the operation portion 21 d protrudes above the case main body 26 through the penetration portion 28. However, when the movable contact 7a is in contact with the fixed contact 6a, it does not necessarily have to protrude.

When the ground fault current is not detected, the energization of the detection unit 2 to the solenoid 22 is stopped, and the electromagnetic solenoid 20 is de-excited. Due to this non-excitation, the attractive force acting in the backward direction with respect to the plunger 23 disappears, and the plunger 23 is displaced in the forward direction by receiving an elastic force from the spring body 24. When power is supplied to the load again, the operation portion 21 protruding from the through portion 28 is used.
d is manually pushed downward, and the latch portion 21 is moved downward along the guide portion 32. The concave portion 21c located above the central axis of the plunger 23 is displaced downward, and the plunger 23
The front end of the spring is engaged with the recess 21 c by the elastic bias of the spring body 24. And the movable spring part 7
The upward movement of the latch portion 21 due to the elastic restoring force is restricted. The lower surface of the contact portion 21b presses the top portion 7c downward against the elastic restoring force of the movable spring portion 7, and the movable contact 7a is fixed to the fixed contact 6a.
To touch. In addition, since the guide part 32 is provided in the case 4 of the present embodiment, the latch part 21 is prevented from falling off when moving in the vertical direction in the case 4, and the movable spring part 7.
The contact reliability with respect to the top portion 7c is increased. Moreover, since the lower surface of the contact part 21b of this embodiment press-contacts with the top part 7c which is a substantially square-shaped bending part, the contact area is small and contact reliability is made high.

The earth leakage relay breaking mechanism 3 according to the present embodiment described above includes an electromagnetic solenoid 20 and a latch portion 21, and the latch portion 21 includes a contact portion 21 b that presses the movable spring portion 7, and an operation portion 21 d. And a recess 21c in which the tip of the plunger 23 is detachably engaged. On the other hand, the leakage relay breaking mechanism 53 described in the prior art includes an electromagnetic solenoid 57 and an operation unit 58.
And a spring 59 and a latch portion 60. That is, in the leakage relay of the conventional example, the three parts of the operation unit 58, the latch unit 60, and the spring 59 are engaged and disengaged. Instead of this, the earth leakage relay of this embodiment has only one component of the latch portion 21. Therefore, the leakage relay of the present embodiment has fewer parts than the conventional leakage relay and has a simple configuration, so that the assembly workability can be improved.

Further, the blocking mechanism 3, the movable spring portion 7, and the fixed terminal portion 6 of the present embodiment can be easily temporarily fixed inside the case 4 by press-fitting or elastic locking as described above. Therefore, since the case 4 can be integrally attached to the printed wiring board 5 after storing the above-described components, the assembly workability can be improved also in this respect.

It is a disassembled perspective view of embodiment of this invention. It is a perspective view in the same as the above. It is a perspective view of the connection part in the same as the above. The top view of a case in the same as the above is shown, (a) is a top view, (b) is a bottom view, and (c) is a bottom view when a blocking mechanism, a movable spring portion, and a fixed terminal portion are attached. The principal part in the same as above is shown, (a) is a perspective view when a ground fault current is not detected, and (b) is a perspective view when a ground fault current is detected. The side view in the same as above is shown, (a) is a right side view when the connecting portion is in contact, and (b) is a right side view when the connecting portion is separated. It is a disassembled perspective view of an example of the conventional earth-leakage relay.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Connection part 2 Detection part 3 Blocking mechanism 4 Case 6 Fixed terminal part 6a Fixed contact 7 Movable spring part 7a Movable contact 20 Electromagnetic solenoid 21 Latch part 21b Abutting part 21c Recessed part 21d Operation part 23 Plunger 28 Through part

Claims (2)

A connection part that connects between the power source and the load, a detection part that detects a ground fault current, a blocking mechanism that cuts off the connection of the connection part according to the detection result of the detection part, is formed in a box shape, A case for housing the blocking mechanism, and the connecting portion includes a fixed terminal portion having a fixed contact at an end portion, a movable contact at one end portion facing the fixed contact, and a fixed other end portion. The interrupting mechanism includes a solenoid energized by detecting a ground fault current, an electromagnetic solenoid having a plunger disposed in the solenoid, and an elasticity of the movable spring portion. The latch is configured to move between a position where the movable contact contacts the fixed contact against a return force and a position where the movable contact moves away from the fixed contact by the elastic return force. Part When the abutting portion disposed at a position facing the spring portion and abutting the movable spring portion, and at least the latch portion is at the separated position, the outside of the case is passed through a through portion that penetrates the case. A concave portion is provided on the wall surface of the latch portion facing the distal end portion of the plunger, the recessed portion with which the distal end portion of the plunger is detachably engaged , and the movable spring portion is The earth leakage relay , wherein the contact portion of the latch portion is in pressure contact with the top portion of the movable spring portion . The earth leakage relay according to claim 1, wherein a guide portion is provided in the case for limiting a moving direction of the latch portion to only the movable direction .

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