JPH0334041Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> The present invention interrupts the circuit when there is no voltage, such as when a power outage occurs, and maintains the circuit disconnected state even when the power outage is restored. This relates to a circuit protector used for the purpose of preventing trouble by blocking the application of voltage to the circuit.

<Prior Art> Conventional circuit protectors are generally designed to protect electrical equipment by allowing a load current to flow directly through a coil and by interrupting the circuit when an excessive current flows. However, in addition to such overcurrent protection, there is a demand for a circuit protector having a structure that interrupts the circuit when there is no voltage and prevents voltage from being applied to electrical equipment or the like when the circuit is restored.

For example, if a power outage occurs while electrical equipment is in operation and the power outage does not recover even after working hours, the operator may turn off the main switch of the electrical equipment because it is not operating. There is a risk that you will forget to cut it and go home. Then, when the power is restored, the power supply voltage will be applied to the electrical equipment with the main switch on without the operator present, which could lead to a very dangerous and serious situation. This will cause trouble.

Therefore, the present applicant devised a new circuit protector that cuts off the circuit when the electrical equipment is in a no-voltage state and prevents the power supply voltage from being applied to the electrical equipment unless a reset operation is performed even after the power is restored.
An application has already been filed as Utility Application No. 1983-33110. Although this circuit protector can achieve the above-mentioned intended purpose, there is still room for further improvement as described below.

<Problems to be solved by the invention> That is, the configuration of this circuit protector can be roughly divided into: a trip actuating means for biasing the trip lever of the trip mechanism in the direction of tripping;
The device is equipped with a trip suppressing means that uses the magnetic force of the coil current to bias the trip lever in a direction in which the trip lever does not operate, regardless of the trip operating means. It is composed of a compression coil spring that biases the upper end of the iron core or the operating end of the trip lever downward;
The trip suppressing means is composed of permanent magnets that repel each other, a fixed core disposed at the upper end of the excited core or the upper end of the coil, and a movable core disposed at the other end so as to be slidable up and down. . by the way,
The trip actuating means requires a biasing force necessary to operate the trip mechanism, while the trip suppressing means prevents the tripping mechanism from tripping against the considerably large biasing force of the tripping mechanism described above. It requires a larger biasing force to hold it in place. Therefore, the coil that serves as the drive source for the trip suppressing means and as the non-voltage detecting means requires a considerable amount of power, resulting in large power consumption and a large size, making it difficult to say that it has high sensitivity.

<Purpose of the invention> The present invention was devised in view of these problems, and it is an object of the present invention to provide a circuit protector that is further improved to operate with high sensitivity using a small coil with low power consumption. The purpose is to

<Means for Solving the Problems> In order to achieve the above object, the circuit protector of the present invention includes a non-voltage detection coil wound around a bobbin having a central hole, an armature which is movably disposed in the coil and whose tip is joined to the yoke by the attraction force generated by energization of the coil to close a magnetic circuit; a locking protrusion, a return spring that biases the armature with a small biasing force due to the attraction force in a direction opposite to the attraction force of the coil, and a movable contact that opens the movable contact with respect to the fixed contact to interrupt the circuit. a trip mechanism, one trip operating end facing the trip mechanism at a position where the trip mechanism can be actuated, and the other operating end rotatably supported to rotate in a direction orthogonal to the moving direction of the armature; The trip mechanism is always urged to rotate in the direction of tripping, and when the armature is connected to the yoke, the edge of the operating end comes into contact with the end surface of the locking protrusion, and the armature is rotated in the return direction. The device is characterized by comprising a trip lever which is rotated by a spring in the trip direction when separated from the yoke so that the end surface of the operation end faces the edge of the locking protrusion so as to prevent the movement of the locking protrusion. be.

<Function> With the above configuration, when the trip is reset with voltage applied to the power supply line, the magnetic force generated by the current flowing through the coil causes
The armature is attracted against the biasing force of the return spring, and the locking protrusion integrally provided on the armature moves to a position facing the operating end of the trip lever, and the operating end abuts the locking protrusion. Rotation of the trip lever in the trip direction is prevented. That is,
Since the trip lever is held in a state in which the trip mechanism is not actuated, the movable and fixed contacts contact each other to maintain the circuit closed. At this time, the locking protrusion protrudes in a direction perpendicular to the moving direction of the armature, and the trip lever comes into contact with the tip of this locking protrusion, so the moving direction of the armature and the rotating direction of the operating end of the trip lever are orthogonal. However, the biasing force of the trip lever has no effect on the movement of the armature. Therefore, the magnetic force generated by the coil may be large enough to attract the armature against the return spring.

When a power outage occurs and the coil is in a no-voltage state, the current stops flowing and the magnetomotive force disappears, so the armature is actuated by the biasing force of the return spring and the locking protrusion detaches from the operating end of the trip lever. do. Therefore, the trip lever, which is always energized, rotates in the tripping direction to operate the tripping mechanism, and a tripping operation is performed to separate the movable contact from the fixed contact and interrupt the circuit. After this, when the power is restored and voltage is applied to the coil again, the armature will be attracted by the magnetic force generated by the coil, but unless the trip mechanism is manually reset, the movable contact will separate from the fixed contact and the circuit will fail. The blocked state is maintained.

<Embodiments> Hereinafter, preferred embodiments of the present invention will be described in detail based on the drawings.

FIG. 1 and FIG. 2 are diagrams showing the internal structure and a partial structure in a state where the trip is returned, respectively;
FIG. 3 is a diagram showing a partial structure in a circuit cutoff state after a trip operation, and FIGS. 4 and 5 are diagrams showing an internal structure and a partial structure, respectively, in an OFF state by manual operation. In these figures, the configuration of the circuit protector of the present invention is roughly divided into a no-voltage detection mechanism A and a trip mechanism B. In the no-voltage detection mechanism A, an armature 3 having an inverted L-shaped cross section is inserted into a central hole 2a of a bobbin 2 around which a coil 1 is wound. The coil 1 is attracted to the right side in each figure by the magnetomotive force generated by energizing the coil 1, and its tip joins the yoke 4, so that the armature 3 and the yoke 4 close a magnetic circuit. A locking protrusion 5 that protrudes in a direction perpendicular to the direction in which the armature 3 swings is integrally provided on the upper part of the armature 3 . Also,
A return spring 6 made of a plate spring is inserted between the hole wall of the central hole 2a of the bobbin 2 and the armature 3, and urges the armature 3 in a direction opposite to the suction direction by the coil 1.

The trip lever 7 for operating the trip mechanism B is
A helical spring 1 is attached to a yoke 9 so as to be rotatable about a pin 8, and is wound around the pin 8.
0, it is always biased in the counterclockwise trip direction in the figure. The lower trip operating end 7a of the trip lever 7 is positioned to operate the trip mechanism B, and the upper operating end 7b is positioned to rotate in a direction perpendicular to the swinging direction of the armature 3. When the armature 3 is attracted to the yoke 4 by the magnetomotive force,
The tip end edge of the operating end 7a is arranged so as to come into contact with the tip surface of the locking protrusion 5 of the armature 3.

Next, in the trip mechanism B, an operating lever 11 for manual operation is rotatably attached to the yoke 9 by a support shaft 12, and a helical spring 13 wound around the support shaft 12 is used to rotate the lever 11 for manual operation. It is constantly biased to rotate clockwise. By operating this operating lever 11, the movable contact 14 can be brought into contact with the fixed contact 15 to return the trip mechanism B, or the movable contact 14 can be separated from the fixed contact 15 to release the trip mechanism B. .

That is, the movable contact plate 16 provided with the movable contacts 14 is rotatably supported along a predetermined direction by a resiliently supported fulcrum. On the other hand, one end of the operation lever 11 that rotates about the support shaft 12 and the first link 17
is connected to one end of the first
The other end of the link 17 and one end of the second link 19 are connected by a pivot pin 20, and the other end of the second link 19 and the middle part of the movable contact plate 16 are connected by a pivot pin 21 to form a quasi-four-bar link mechanism. furthermore, the trip lever 7 is more
A pin 22 is installed at a position close to the
The structure includes a trip rod 23 that is integrated with 2. The above-mentioned elastic support means for the movable contact plate 16 is provided by drilling a long hole (not shown) in a predetermined direction in the supporting portion of the movable contact plate 16, and inserting the fixing pin 24 provided on the yoke 9 into the long hole. The movable contact plate 16 is connected to the movable contact plate 16 by a helical spring 25 that is inserted through the
The support part is pressed in a direction approaching the operating lever 11, that is, in a counterclockwise direction in the figure.

Further, the trip rod 23 provided on the second link 19 has an arm portion 23a parallel to the second link 19, and a receiving portion 23b bent in a right angle direction from the tip thereof. Further, the second link 19 is formed with a stopper 19a whose side end adjacent to the trip rod 23 is bent in a right angle direction. The trip rod 23 is constantly pressed against the stopper 19a with a slight force by a helical spring (not shown) wound around the pin 22.

On the other hand, the tip of the active end 7a of the trip lever 7 is located at the tip of the operating end 7a that comes into contact with the receiving portion 23b of the trip lever 23 when the trip lever 7 is rotated counterclockwise when the operation lever 11 is in the on state shown in FIGS. 1 and 2. The vicinity of the first kick-off point forms a first flat surface 7c that generates an effective kick-off moment,
When the operating lever 11 shown in FIG. 3 is in the reset position, the second
The vicinity of the kick-off point forms a second flat surface 7d that generates an effective kick-off moment, and a stepped portion 7e is formed between the first flat surface 7c and the second flat surface 7d. As a result, the second flat surface 7c is smaller than the first flat surface 7c.
The flat surface 7d has a protruding shape toward the right.

The trip lever 7 is integrally provided with a reset plate 26 for rotating the trip lever 7 clockwise by operating the operating lever 11. This reset plate 26 is formed of the same member as the trip lever 7, is positioned parallel to the trip lever 7, and rotates together with the trip lever 7 by a pin 8. This upper end face faces a connecting pin 18 between the operating lever 11 and the first link 17 that extends rearward in the figure.
A protrusion 26a is formed that enters the rotation locus of the connection pin 18, which is indicated by a broken line arrow in FIG. The pin 18 comes into contact with the protrusion 26a and slides, causing the reset plate 26, that is, the trip lever 7, to rotate clockwise. Further, the helical spring 10 that biases the trip lever 7 and the reset plate 26 has a greater spring pressure than the helical spring 13 that biases the operating lever 11.

Next, the operation of the above embodiment will be explained.
As shown in FIG. 6, the terminals of both contacts 14 and 15 are connected in series to the power supply circuit of the load L to be protected, and the lead wire of the coil 1 is connected in parallel to the power supply AC.
However, if the power supply AC is alternating current as shown in the figure, it should be replaced with direct current using a rectifier RC.

When the operating lever 11 is rotated from the OFF position shown by the two-dot chain line in FIG. 3 to the ON position shown by the one-dot chain line in FIG. When the reset position shown by the solid line in the figure is reached, the connecting pin 18
slides in contact with the protrusion 26a of the reset plate 26, and the protrusion 26a is pushed down by the connecting pin 18, so that the reset plate 26 and the trip lever 7 integrated therewith are rotated clockwise, that is, in the anti-trip direction. the operating end 7 of the trip lever 7
b moves upward. The armature 3, which had been prevented from rotating by the locking protrusion 5 in contact with the operating end 7b, was attracted by the magnetic force generated by the coil 1, swung to the right, and moved to the right together with the armature 3. When the tip of the locking protrusion 5 comes into contact with the working end 7b of the trip lever 7, rotation of the trip lever 7 in the counterclockwise direction, that is, in the trip direction, due to the bias of the helical spring 10 is prevented. On the other hand, operation lever 1
1, the trip mechanism moves the movable contact plate 16
The movable contact 14 moves downward against the biasing force of the helical spring 25, and the movable contact 14 contacts the fixed contact 15 as shown in FIG. 1, thereby closing the power supply circuit.

Here, when a power outage occurs and the coil 1 becomes a no-voltage state, the magnetomotive force generated by the current flowing through the coil 1 disappears, so the armature 3 is activated by the return spring 6 as shown in FIGS. It swings to the left as shown in Figure 5. The locking protrusion 5 integrated with the armature 3 is the operating end 7b of the trip lever 7.
In order to separate from the trip lever 7, the trip lever 7, which is biased by the helical spring 10, rotates in the trip direction. Before the trip lever 7 rotates, as shown in FIG. 1, the first flat surface 7c at the working end 7a of the trip lever 7
3, the trip lever 23 is kicked out by the rotation of the trip lever 7. That is, the trip rod 23 is rotated counterclockwise, and when the trip rod 23 rotates together with the trip rod 23, the pin 22 causes the first
The link 17 and the second link 19 are bent, and the movable contact 14 is separated from the fixed contact 15.

At this time, the operating lever 11 also tries to rotate from the on position to the off position, but the reset plate 26 integrated with the trip lever 7, which has been rotated in the trip direction, also returns to the state shown in FIG. Therefore, the connecting pin 18 touches the protrusion 26 of the reset plate 26.
a, and the trip lever 7 is again rotated in the anti-trip direction as shown in FIG. 3 via the reset plate 26. Here, since the spring pressure of the helical spring 10 for biasing the trip lever 7 is greater than that of the helical spring 13 for biasing the operating lever 7,
The operating lever 11 is stopped at the reset position shown in FIG. This makes it possible to display that the circuit is interrupted due to a power outage, and when the operator manually interrupts the circuit, the operating lever 11 will be in the OFF position, so the cause of the circuit interruption can be clearly distinguished. can.

When the power is restored and the coil 1 is energized when the operating lever 11 is in the reset position and the circuit is interrupted, the operating end 7b of the trip lever 7 is positioned upward and there is no obstruction to the movement of the stop protrusion 5. Therefore, the armature 3 swings to the right, but the link mechanism does not operate at all and maintains the circuit-broken state. Then, after the power supply voltage is applied to the coil 1 again in this way, when the operator turns the operating lever 7 to the OFF position, the first link 17 and the second link 19 return to their original engagement relationship. and become one. This mechanism is well known and is not directly related to the gist of the present invention, so its explanation will be omitted.

In addition, when the power outage has not been restored, the operation lever 1
1 is returned to the off position and then turned to the on position, the armature 3 is tilted to the left and the locking protrusion 5 is separated from the operating end 7b of the trip lever 7, so the connecting pin 18 is reset. When passing the protrusion 26a of the plate 26, the trip lever 7 rotates in the trip direction due to the biasing force of the helical spring 10 and kicks out the trip rod 23, and the trip mechanism B immediately trips and the movable contact 14 turns off. Return to position.

In this way, this circuit protector can cut off the circuit if the power supply goes into a no-voltage state and maintain this state even after recovery, so there is no danger of the power being accidentally turned on to electrical equipment, etc. This can be prevented from occurring.

In addition, the circuit protector of the present invention can be used with conventional overcurrent type circuit breakers, as shown in Figure 7.
It can also be installed in parallel with the SB in a two-pole configuration that protects against overcurrent and shuts off when there is no voltage.

<Effects of the invention> As detailed above, according to the circuit protector of the invention, it is possible to cut off the circuit when the power supply becomes non-voltage, and to maintain the circuit cut-off state even after the power is restored unless manual operation is performed. Therefore, it is possible to reliably prevent electrical equipment from being inadvertently turned on and creating a dangerous situation, for example, when a power outage is restored.

Moreover, the armature that operates the trip suppressing means, which uses the attractive force of the coil as a non-voltage detection means to bias the trip mechanism B in the direction of not tripping, is arranged perpendicularly to the rotating direction of the operating end of the trip lever. A lock that is actuated in a direction perpendicular to the rotational direction of the operating end from the armature, and that protrudes from the armature in the rotational direction of the operating end and comes into contact with the trip lever to prevent rotation in the tripping direction. Because of the structure with the protruding piece, the attraction force of the coil can be extremely small compared to the case where the attraction force of the coil is applied in the rotational direction of the trip lever and this rotational force is directly blocked. By using smaller items, the overall shape can be made smaller, and
It consumes less power and has great economic effects. Also,
The small attraction force of the coil allows it to respond with high sensitivity and improve reliability.

[Brief explanation of the drawing]

1 to 5 each show an embodiment of the circuit protector of the present invention. Figure 3 is a partial structural diagram of the reset state, Figures 4 and 5.
The figures are an internal structure diagram and a partial structure diagram in the OFF state by manual operation, Figure 6 is a circuit diagram using the circuit protector of the present invention, and Figure 7 is a circuit diagram of the circuit protector of the present invention without voltage. FIG. 3 is a circuit diagram of a circuit protector with a release function. 1... Coil, 2... Bobbin, 2a... Center hole, 3... Armature, 4... Yoke, 5...
Locking protrusion, 6... Return spring, 7... Trip lever, 7a... Trip action end, 7b... Operating end,
14...Movable contact, 15...Fixed contact, B...Trip mechanism.

Claims (1)

[Scope of utility model registration request] A no-voltage detection coil is wound around a bobbin with a central hole, and the coil is movably disposed within the central hole, and the tip is joined to the yoke by the attraction force generated by energizing the coil, forming a magnetic circuit. an armature for closing the armature; a locking protrusion integrally protruding from the armature in a direction perpendicular to the direction of movement of the armature; a return spring that is biased by a force; a trip mechanism that opens a movable contact with respect to a fixed contact to interrupt a circuit; one trip action end is opposed to a position where the trip mechanism can be operated, and the other operation end is is rotatably supported to rotate in a direction perpendicular to the direction of movement of the armature, and is constantly biased to rotate in a direction that causes the trip mechanism to perform a trip operation, and when the armature is connected to the yoke, the operation is performed. The end edge portion of the end is brought into contact with the end face of the locking protrusion, and when the armature is separated from the yoke by the return spring, the armature is rotated in the trip direction so that the end face of the operating end is brought into contact with the end face of the locking protrusion. 1. A circuit protector comprising a trip lever opposing the edge of the circuit protector to prevent movement.