JPH0238362Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a breaker equipped with an earth leakage tripping mechanism that detects earth leakage and opens the contacts.

Some breakers of this type use a display body to indicate current leakage, and the display body is normally biased upward by a spring and is normally restricted from moving upwards, so that when a current leakage is detected, the display body The current leakage information is displayed by removing the movement restriction and causing the display to protrude from the top surface of the case, for example.

By the way, in this type of breaker, the restriction on movement of the display body is released (hereinafter, this operation is Because the opening/closing mechanism that opens and closes the contacts is driven simultaneously, the opening/closing mechanism is tripped and the operation affects the opening/closing mechanism of the display. There was a problem that the release operation became uncertain.

In addition, with this type of breaker whose operating handle has only two operating positions, ON and OFF, when the operating handle is manually rotated to the OFF position, the movement of the display may be restricted due to vibrations. When it is released, the display state becomes the same as when the leakage occurred, and there was also a problem that it was not possible to distinguish between the above state and the display state of the electrical leakage.

The present invention has been devised in view of the above-mentioned points, and its purpose is to provide a breaker that can provide reliable leakage indication.

Embodiments of the present invention will be described below with reference to the drawings.
The breaker of this embodiment operates the switching mechanism to open the contacts when an abnormality in the load current occurs.
It cuts off the power supply to the load, and detects short-circuit current using a solenoid 2, overcurrent using a bimetal 1, and leakage using a zero-phase current transformer 41. solenoid 2
As shown in FIG. 1B, the plunger 22 is composed of a coil 21 through which a load current flows, and a plunger 22 which is attracted and driven by the magnetomotive force of the coil 21. Also,
The opening/closing mechanism section is the plunger 2 of the solenoid 2.
a hanging piece 31 with one end of the two facing each other with a small gap;
and a bimetal 1 whose one end is fixed to the frame 4
The tripping link 3 is formed with a horizontal piece 32 whose other end, which is a free end, is located downward when the temperature rises, and is pivotally supported on the frame 4 by a shaft 10, and the tripping link 3 projects upwardly. A latch link 11 is formed with an engagement hole 12 in which a locking protrusion 33 engages and is pivotally supported on the frame 4, and a vertically elongated hole 13 formed approximately directly below the pivot point of the latch link 11 and the frame 4.
The movable shaft 1 is engaged with a horizontally elongated hole 19 formed in the
The link 14 has one end connected to the latch link 11 at 8, the links 15 and 16 connect to the other end of the link 14 through a connecting shaft 81 attached to a window 82 formed in the frame 4, and the other end of the link 16. a link 17 which is movably connected at one end to the frame 4 and pivots integrally with the operating handle 8; and a return spring 35 which returns the trip link 3 to the state shown in FIG. 1b during normal operation. , a return spring 80 that is attached to the interlocking shaft 81 and rotates the operating handle 8 back to the off position, and an opening spring 29 that applies an opening force to each of the links. The movable contact 5 driven by this opening/closing mechanism has a movable contact 26 fixed to the lower end opposite to the fixed contact 25.
The upper end is pivotally supported by a pivot shaft 27 fixed to the frame 4, and the approximately central part is connected to the other end of the link 15 by a connecting shaft 20.
The contact pressure is obtained by applying spring pressure to a portion between the connecting shaft 20 and the pivot shaft 27 using an opening spring 29. The other end of the plunger 22 is engaged with the movable contact 5. The case of this breaker consists of a body 61 and a cover 44 that covers the body 61.
As shown in Figure a, the left and right poles are arranged on the body 61.

By the way, when the connecting shaft 81 that connects the links 14 to 16 is turned on and off using the operating handle 8, an abnormal current is detected and the latched state of the tripping link 3 and the latch link 11 is released and the contacts 25 and 26 are turned on and off. a tripping stroke in which the
A substantially triangular locus is drawn in a series of strokes in which the links 14 to 17 trip and the operation handle 8 returns to the OFF state. Therefore, a window 82 for mounting the connecting shaft 81 is formed in the shape shown in FIG. 4. A protrusion 83 is formed at a portion of the window 82 that is approximately at the center of the trajectory of the operating handle 8 in its return stroke, and the interlocking shaft is moved during the return stroke in which the operating handle 8 is returned to the OFF state by the return spring 80. 81 is engaged with the protrusion 83 to stop the counterclockwise rotation of the operating handle 8 and neutralize the operating handle 8, and the contacts 25 and 2 are manually operated.
The open state of contact points 6 and the open state of contacts 25 and 26 when an abnormality occurs can be distinguished from each other.

As shown in FIG. 2, the earth leakage detection unit that detects earth leakage includes a zero-phase current transformer 41 that detects the zero-phase current transformer of the load current, and an amplifier circuit that amplifies the output of this zero-phase current transformer 41. 74, and the output of the amplifier circuit 74 drives the earth leakage tripping mechanism 50 that trips the opening/closing mechanism. Earth leakage tripping mechanism section 50
is arranged between the above-mentioned left and right poles, and as shown in FIG.
The coil block 42 through which current is passed through the coil block 77 and the through hole 58 of the coil bobbin 78 around which the coil 77 is wound are biased by a spring 62 in the direction of coming out of the through hole 58 when the coil block 42 is not energized, so that it can move forward and backward. It consists of a plunger 47 that is inserted and is attracted and driven when the coil block 42 is energized, and a display 46 that projects from the top surface of the cover 44 and displays an earth leakage indication when the coil block 42 is energized. Here, plunger 47 of coil bobbin 78
A box-shaped part 60 that opens upward is formed on the flange opposite to the insertion side, and the display body 42 is housed in this box-shaped part 60 while being biased upward by a spring 64. Note that a yoke 43 is attached to this coil block 42 in order to increase magnetic efficiency. The plunger 47 has a cylindrical shape with a through hole 70, and is integrally connected to a trip bar 48 that releases the display 46 and trips the opening/closing mechanism. The tripping lever 48 is integrally connected by fitting the protruding piece 68 into the through hole 70 of the plunger 47.
The base of the protruding piece 68 is widened in the vertical direction to form a step 71, and a driving piece 69 for driving the tripping link 3 of the opening/closing mechanism is protruded laterally. The display body 46 integrally includes a display button 45 that projects from the cover 44 and indicates the current leakage state, and a reset piece 76 that resets the display body 46 by operating the operating handle 8.

By the way, when the yoke 43 is fitted to the coil block 42 and the display body 46 is housed in the box-shaped part 60, the tripping lever 48 is moved to the side wall of the box-shaped part 60 on the opposite side from the insertion side of the plunger 47. Insert from the side. For this purpose, the inside of the box-shaped part 60 is communicated with the through-hole 58, and an insertion hole 79 for inserting the tripping lever 48 is formed in the side wall of the box-shaped part 60 opposite to the insertion side of the plunger 47. 43, holes 54, 5 which communicate with the through hole 58 and the insertion hole 79, respectively.
5 is formed, and the display body 46 is further provided with a tripping lever 4.
A vertically elongated hole 63 into which the hole 8 is inserted is formed. Here, the wide part of the stepped part 71 of the tripping lever 48 is located within the vertical hole 63 when the coil block 42 is not energized, and restricts the upward movement of the display 46, while the narrow part is energized. It is formed so as to be located within the vertically elongated hole 63 and to release the restriction on upward movement of the display body 46. Further, the drive piece 69 of the tripping lever 48 is activated by the excitation of the coil block 42 to move the step portion 7 .
After the narrow portion of the opening/closing mechanism 1 is located in the vertical hole 63 of the display body 46, the latching state between the trip link 3 and the latch link 11 of the opening/closing mechanism is released and the opening/closing mechanism is tripped. . Furthermore, in order to drive the reset piece 76 of the display body 46, as shown in FIG. 1b or FIG. The left end of the reset piece 76 is used as a pressing part 85 for pressing the reset piece 76. This pressing portion 85 faces the reset piece 76 when the opening/closing mechanism is tripped, and when the operation handle 8 is rotated from the neutral position to the off operation position, it rotates from above to downward and pushes down the reset piece 76. ,
The display body 46 is housed within the box-shaped portion 60.

FIG. 1 is a diagram showing the on state of the breaker,
The trip link 3 and the latch link 11 are engaged,
The movable contact 5 is pushed to the right in the figure by the linkages 14 to 17, and the fixed contact 25 and the movable contact 26
are in contact with. Note that contact pressure is appropriately applied to the contacts 25 and 26 by a rotational moment caused by the biasing force of the opening spring 29 about the connecting shaft 20.

If the operating handle 8 is rotated counterclockwise in the figure from this state, the link 16 will be pulled up, and the joints of the links 14 to 16, which have become linked to prevent the mutual movement of the opening/closing mechanism parts, will collapse. The tripping action is performed by the biasing force of the opening spring 29, and at this time, the movable contact 5 rotates clockwise around the pivot shaft 27, and the contacts 25 and 26 are opened and separated.

If an abnormality such as a short circuit occurs in the on state, the following operation occurs. Now, if the load current flowing from the fixed contact 25 to the movable contact 26, the movable contact 5, the braided copper wire, the bimetal 1, and the coil 21 becomes an overcurrent, the bimetal 1 will flow as shown in Fig. 7c. The spring 35 is displaced and returns the trip link.
When a short circuit current flows, the plunger 22 presses the hanging piece 31 of the tripping link 3 and rotates the tripping link 3, as shown in No. 7b. and the latch link 11, break the joints of the links 14 to 16 that have become linked to prevent mutual movement of the opening/closing mechanism, and trip the opening/closing mechanism by the biasing force of the contact pressure spring 29. At this time, the movable contactor 5 rotates around the pivot shaft 27, and the contacts 25, 26
is released. Here, when a short circuit current flows, the plunger 22 of the solenoid 2 that engages with the movable contact 5 forcibly rotates the movable contact 5 to instantly open the contacts 25 and 26. It is set as.

In addition, when resetting the opening/closing mechanism that has been tripped in this way, as shown in Figure 7a,
The operating handle 8 is once turned off, the trip link 3 and the latch link 11 are re-engaged, and then the operating handle 8 is turned on.

The operation at the time of earth leakage detection will be explained below. first,
When no current leakage occurs, the coil block 42 is in a non-excited state, so the plunger 47 is moved into the through hole 5 of the coil bobbin 78 by the return spring 62.
The wide part of the stepped part 71 of the tripping lever 48 that protrudes in the direction of exiting from the display button 4 and operates integrally with the plunger 47 fits into the vertical hole 6 of the display body 46, and the display button 4
5 from protruding from the upper surface of the cover 44.

If a leakage occurs now, the zero-phase current transformer 41
The zero-phase current transformation component of the load current is detected, and the detected output is amplified by the amplifier circuit 74, and current flows through the coil 77 as an output. Then, the coil block 42 is excited and the plunger 47 is attracted, and at this time, the wide part of the stepped part 71 first comes out of the vertically long hole 63 of the display body 46, and the wide part of the stepped part 71 is located inside the vertically long hole 63, The state that restricts the upward movement of the display body 46 is released (the display body 46 is released), and the return spring 6
4, the display body 46 is pushed up and the display button 45
protrudes from the upper surface of the cover 44. That is, the electric leakage is displayed by the state in which the display button 45 protrudes from the cover 44. Then, the tripping lever 48
By pressing the tripping link 3, the latching state between the tripping link 3 and the latch link 11 is released, and the opening/closing mechanism is tripped in the same way as when detecting an abnormal current such as an overcurrent described above, and the contact is 2
5 and 26 are opened. In addition, the tripping lever 48
When the right trip link 3 is rotated, the left trip link 3 and the latch link 11 are also unlatched by the connecting rod 75.

The display 46 can be reset by moving the operating handle 8 from the neutral position to the off operating position with the display button 45 protruding from the top surface of the cover 44 and the opening/closing mechanism tripped to make the operating handle 8 neutral as described above. Perform rotation operation. At this time, the pressing part 85 of the operating handle 8 rotates downward from above,
At this time, it comes into contact with the reset piece 76 and the reset piece 7
By pushing down 6, the display body 46 is housed in the box-shaped part 60. At this time, coil block 4
2 is in a de-energized state, the plunger 47 is urged by the return spring 62 in the direction in which it protrudes, and when the display body 46 is accommodated in the box-shaped part 60 to a predetermined position, the step of the tripping lever 48 is The wide part of the portion 71 is inserted into the vertically elongated hole 63, and therefore the upward movement of the display body 46 is restricted, that is, the display body 46
is reset.

As described above, the present invention includes a zero-phase current transformer that detects leakage from the zero-phase transformer of a load current, a coil block through which a current according to the output of the zero-phase current transformer flows through the coil, and A plunger is inserted into the through hole of the coil bobbin wound with the coil bobbin so that it can move forward and backward while being biased by a spring in the direction of exiting from the through hole when the coil block is not energized, and is attracted and driven when the coil block is energized. An opening/closing mechanism section that opens and closes the contact at the time of tripping, and also stops the rotation of the operating handle at approximately the intermediate position between the on and off operating positions when the contact is manually opened and closed during tripping, and the coil block. and a display body that projects from the top surface of the case when energized to display an earth leakage indication, and the display body is housed in a box-shaped part formed on one of the flanges of the coil bobbin and having an open top surface with the display body biased upwardly by a spring. , a through hole is formed in the display body through which the plunger is inserted, and when the coil block is not energized, the wide part in the vertical direction is located in the through hole to restrict the upward movement of the display body, and when the coil block is energized, The plunger is formed with a stepped part whose narrow part is located in the through hole to release the restriction on upward movement of the display, so that when an electric leakage is detected and the plunger is suction driven, the display will not move. The narrow part of the stepped part of the plunger is located within the through hole, releasing the restriction on upward movement of the display body, and causing the spring-biased display body to move upward and protrude from the top surface of the case. Electrical leakage can be indicated by the protrusion of the body. In addition, after the narrow part of the stepped part of the plunger is located in the through hole of the display body by energizing the coil block, the tripping link and the latch link of the opening/closing mechanism are released from the latched state and the opening/closing mechanism is tripped. Since the piece is formed into a plunger, releasing the display and tripping the opening/closing mechanism can be performed independently, and the action of tripping the opening/closing mechanism influences the release of the display, causing the display to There is no uncertainty in the release operation. Furthermore, when the opening/closing mechanism is tripped, the rotation of the operating handle is stopped at approximately the midpoint between the on and off operating positions when the opening/closing poles of the contacts are manually operated. The display body faces the pressing part formed on the pivoted base of the handle, and comes into contact with the pressing part that rotates from the top to the bottom when the operating handle is rotated from the neutral position to the off operating position. Since the display body has a reset piece that can be pushed down and placed in the box-shaped part, the earth leakage display is always reset when the operating handle is turned off, and the earth leakage display will not be displayed while the operating handle is turned off. Therefore, if the upward movement of the display is lifted due to vibration, for example, it is not possible to judge whether the display is stationary or not based on whether the operating handle is in the neutral state. , it has the advantage of being able to provide reliable earth leakage indication.

[Brief explanation of the drawing]

Figures 1a and b are a plan view and a sectional view of an embodiment of the present invention, Figure 2 is a sectional view of the same, Figure 3 is an exploded perspective view of the trip mechanism of the above, and Figure 4 is a diagram of the trip mechanism of the same. FIG. 5 is an enlarged exploded perspective view of the earth leakage tripping block, FIG. 6 is an enlarged perspective view of the earth leakage tripping block, and FIGS. 7a to 7c are explanatory diagrams of the operation. 3 is a trip link, 11 is a latch link, 8 is an operating handle, 25 is a fixed contact, 26 is a movable contact, 41 is a zero-phase current transformer, 42 is a coil block,
44 is a cover, 45 is a display button, 46 is a display body, 4
7 is a plunger, 48 is a tripping lever, 58 is a through hole, 60 is a box-shaped portion, 62 and 64 are return springs, 6
9 is a drive piece, 71 is a stepped portion, 76 is a reset piece, 7
7 is a coil, 78 is a coil bobbin, and 85 is a pressing portion.

Claims (1)

[Scope of utility model registration request] A zero-phase current transformer that detects earth leakage from the zero-phase current of the load current, a coil block through which a current according to the output of the zero-phase current transformer is passed through the coil, and a through hole in the coil bobbin around which the above-mentioned coil is wound. When the coil block is not energized, the plunger is inserted into the through-hole so that it can move forward and backward while being biased by a spring, and is driven by attraction when the coil block is energized.The plunger is trip-driven to open the contact and , an opening/closing mechanism that stops rotation of the operating handle approximately halfway between the ON and OFF operating positions when the contact is manually switched during tripping, and an earth leakage indicator that protrudes from the top of the case when the coil block is energized. The display body is housed in a box-shaped part formed on one of the flanges of the coil bobbin and has an open top surface, with the display body biased upward by a spring, and a plunger is inserted through the display body. When the coil block is not energized, the wide part in the vertical direction is located within the through hole to restrict upward movement of the display, and when energized, the narrow part is located within the through hole. A step part is formed on the plunger to release the restriction on the upward movement of the display body, and after the narrow part of the step part of the plunger is located in the through hole of the display body by excitation of the coil block, the opening/closing mechanism is opened. A drive piece is formed on the plunger to release the latched state between the trip link and the latch link and trip the opening/closing mechanism, and is opposed to a pressing part formed on the pivoted base of the operating handle when the opening/closing mechanism is tripped. A reset piece is formed on the display body to push down the display body and fit it into the box-shaped portion by coming into contact with a pressing portion that rotates from the top to the bottom when the operation handle is rotated from the neutral position to the off operation position. A breaker characterized by: