JPH0228215B2 - DENJISHADANKI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electromagnetic breaker with improved interrupting performance.

[Prior art and its problems]

In conventional electromagnetic breakers, for example,
As in the configuration described in Japanese Patent No. 24211, a selection plate is connected to the movable rod, and the selection plate and the movable iron core are connected in a detachable manner. This selection plate is interlocked with the arm of the catch section, and rotates when the catch mechanism is tripped by short-circuit current or the like. At this time, the engagement between the selection plate and the movable iron core is released, and the movable rod is opened by the force of the stored spring.

However, with such conventional mechanisms, there is a problem that the selection plate is located between the arm and the movable rod, which slows down the time it takes to shut off, and that the number of parts increases, making assembly difficult and increasing costs. Ta.

[Purpose of the invention]

The present invention solves these conventional problems and
The purpose is to improve the interrupting performance by increasing the interrupting speed, reduce costs by reducing the number of parts and assembly man-hours, and downsize the device.

[Structure of the invention]

The present invention provides a fixed iron core wrapped with an excitation coil;
In an electromagnetic breaker, the electromagnetic breaker includes a movable core that attracts the fixed core, and a movable rod that is connected to the movable core and has a movable contact that moves toward and away from the fixed contact that can be raised and lowered. It is installed between the movable iron core and the movable rod, which are connected to each other so as to have a required stroke play in the direction, and biases the movable rod in the direction of attracting the movable rod toward the movable iron core within the stroke. connection spring,
a contact spring provided on the movable rod and applying contact pressure to the movable contact with respect to the fixed contact;
When the movable contact rises while the movable rod remains stationary due to an electromagnetic repulsive force that is provided on the movable rod and acts when an excessive current flows through both contacts of the fixed contact and the fixed contact, a latch metal fitting having a hook portion that engages with an engagement groove provided in the movable contact; and a latch metal fitting provided at a tip end of the latch metal fitting;
When the movable rod is raised, it collides with a protrusion provided on the case side, thereby tilting the latch metal fitting against the biasing force of the latch spring, disengaging the engagement groove from the hook portion, and disengaging the movable contactor. a latch return piece that lowers the latch; a trip coil that is provided in the case and is excited by the excessive current that flows through both the contacts of the movable contact and the fixed contact; a tilting catch arm; an arm whose base end engages with the distal end engaging portion of the non-tilting catch arm and whose distal end engages with the movable rod; and an arm provided between the arm and the case; The arm is compressed when the catch arm is engaged with the catch arm, and when the engagement state is released by tilting the catch arm due to excitation of the trip coil, a restoring force is applied to the arm and the biasing force of the connection spring is increased. a biasing spring that acts in a direction to separate the movable rod from the movable iron core; a contact that is pushed by the catch arm when the catch arm is tilted and cuts off the energization to the excitation coil; The device is characterized in that it is provided with a reset handle for returning to the engagement state with the catch arm.

〔Example〕

Hereinafter, the present invention will be explained based on embodiments shown in the drawings. FIG. 1a is a sectional view showing the structure of the electromagnetic circuit breaker according to the present invention, in which 1 is a case body, 2 is a fixed core, 3 is an exciting coil, 4 is a coil frame, and 5 is a fixed core that connects the coil frame 4 to the fixed core. 2 is a coil spring that cushions and supports 2, 6 is a spring seat, 7 is a substrate that fixes fixed iron core 2, 8 is a movable iron core, 9 is a movable rod, and 10 is between the movable rod 9 and the movable iron core 8. The connecting spring 11 is a spring seat that connects the movable core 8 and the movable rod 9 while applying the repulsive force of the spring to the movable core 8. The spring seat 12 restores the movable core 8 and the movable rod 9 upward when not energized. The repulsion spring 13 is attached to the upper part of the movable rod 9.
A movable contactor, 14, which is provided so as to be able to rise and fall freely relative to the
is a fixed contact that this movable contact 13 approaches and separates, 1
5 is a contact spring that applies contact pressure to the movable contact 13; 16 is a fixed contact 14 and a movable contact 13;
When the movable contact 13 rises while the movable rod 9 remains stationary due to the electromagnetic repulsion force acting between both contacts when an excessive current flows, the movable contact 13 engages with the engagement groove 17 provided in the movable contact 13. A latch metal fitting 19 is a latch return piece formed at the tip of the latch metal fitting 16, and 19 is a latch return piece formed at the tip of the latch metal fitting 16.
When it rises, it collides with the protrusion 20 provided on the case 1 side, thereby tilting the latch fitting 16,
The movable contact 13 is lowered by disengaging the engagement groove 17 and the hook portion 18.

Further, 21 is a latch spring for restoring the latch fitting 16 from the state shown by the dashed line shown in FIG. 1B to the state shown by the solid line, 22 is a catch mechanism reset handle, and 23 is operated by the catch mechanism shown in FIG. 7. It is an arm.

Now, to explain the catch mechanism, as shown in FIG. 7a, in normal use, the arm 23 is engaged with the catch arm 25 which is tilted by the trip coil 24, but a short circuit current flows between the contacts. If the current causes a large current to flow through the trip coil 24, the catch arm 25 tilts and disengages the arm 23, and the restoring force of the biasing spring 26 causes the arm 2 to tilt as shown in FIG.
This is a configuration that increases 3. FIG. 7c shows a state in which the electromagnet is de-energized and the movable core is opened after the trip.

In this embodiment, FIG. 1a shows the normal state in which the handle is in the closed state and the contacts 13 and 14 are also in contact.

FIG. 2 shows a state in which an excessive short circuit current, for example, a current of 3 KA or more flows between the contacts 13 and 14, and the movable contact opens and is interrupted. In this case, currents in different directions flow between the movable contact 13 and the fixed contact 14, and the electromagnetic repulsion force overcomes the pressing force of the contact spring 15, causing the movable contact 13 to rise and the latch fitting 16 is rotated, the hook portion 18 and the engagement groove 17 engage with each other, and the movable contact 13 is locked. In this state, the catch mechanism is on and the coil is energized. For example, in an electromagnetic breaker with a rated current of 20 A (the same applies to the following examples), the operating time is about 1 to 3 ms from the time when a short circuit current occurs.

FIG. 3 shows the operation when the catch mechanism shown in FIG. 7 performs a tripping operation and the arm 23 rises. The movable rod 9 is pushed up by the arm 23, and the opening of the contact points becomes even larger. Here, the pressing force of the arm 23 is the coupling spring 10
The spring force must be greater than the spring force. In this state, the excitation of the coil 3 has just been cut off, and the iron cores 2 and 8 are still in an attracted state. A contact 27 is connected in series to the coil 3 as shown in FIG.
This contact 27 is configured to work in conjunction with the catch mechanism and to be disconnected when the catch mechanism is actuated. In the case of the above-mentioned type of electromagnetic breaker, the operating time is about 3.5 to 6 ms from the time when a short circuit current occurs.

In addition, FIG. 6 shows a state in which a short circuit current that does not lead to locking operation, for example, a current of less than 3 KA, flows.As in FIG. 3, the movable rod 9 is pushed up by the arm 23 and the contact opens, but the contact opens. Since the electromagnetic repulsive force acting on the movable contact 13 is small and there is no locked state, it is smaller than the state shown in FIG. 3.

Figure 4 shows that the catch mechanism is activated and the movable iron core 2
The iron cores 2 and 8 are separated by the repulsion spring 12, and the movable rod 9 is opened to the stopper portion of the container box 1. At this time, the latch return piece 19 of the latch fitting 16 and the protrusion 20 of the container box 1 abut against each other, and the latch fitting 16 is rotated to disengage the hook 18 and the engagement groove 17, thereby releasing the lock. The operating time is about 9 to 12 ms in the above-mentioned rated current 20A type electromagnetic breaker after the short circuit current occurs.

Figure 5 shows a state in which the reset handle is activated and the electromagnet is not energized during reuse.
The catch mechanism returns to engagement and the arm 23 moves toward the coil frame 4, so that the movable rod 9 becomes ready to be loaded.

In addition, in the embodiment described above, the connection spring 10
was provided between the movable rod 9 and the movable iron core 8, but the 9th
As shown in the figure, a similar operation can be achieved even if a connecting spring 10' is provided between the case 1 and the movable rod 9, and the movable rod 9 is pushed up by the arm 23 of the catch mechanism.

In addition, in the embodiment described above, the connection spring 10
An example is shown in which a coil spring is used, but this is constructed with a plate spring 10'' as shown in Fig. 10,
This also allows the spring seat 11 to be omitted.

〔Effect of the invention〕

As described above, the present invention provides the following effects.

(a) When the short-circuit current reaches the set value or more, even if the movable core is still in the attracted state, the catch arm is pushed up, leaving the movable core behind and only the movable rod is raised to rapidly open the movable contact. ,
In addition, a large blocking distance can be achieved.

(b) It can be cut off relatively quickly even in a small current range, so
It has little effect on the tripping section, has a small capacity rating, and can have a large breaking capacity.

(c) It has a relatively simple structure, and can be made low-cost and compact.

[Brief explanation of drawings]

FIG. 1a is a cross-sectional view showing the normal energized state of the electromagnetic breaker according to the present invention, FIG. 1b is a side view of the main part thereof, FIG. The figure is a cross-sectional view showing the secondary cut-off state.
Fig. 4 is a cross-sectional view showing the trip state, Fig. 5 is a cross-sectional view showing the reset state, and Fig. 6 is a cross-sectional view showing the cut-off state when a short-circuit current lower than the lock operating current flows and only the tripping device is activated. , FIG. 7 is an explanatory view showing the operation of the catch mechanism, FIG. 8 is a partially cutaway side view of this embodiment, and FIGS. 9 and 10 are schematic views showing other examples of the present invention. be. 1: Case body, 2: Fixed core, 3: Excitation coil, 4: Coil frame, 5: Coil spring, 6:
Spring seat, 7: Board, 8: Movable iron core, 9: Movable rod, 10: Connection spring, 10': Connection spring, 10'': Leaf spring, 11: Spring seat,
12: Repulsion spring, 13: Movable contact, 1
4: Fixed contact, 15: Contact spring, 16:
Latch fitting, 17: Engagement groove, 18: Hook part, 1
9: Latch return piece, 20: Projection, 21: Latch spring, 22: Reset handle, 23: Arm, 24: Trip coil, 25: Catch arm, 26: Biasing spring, 27: Contact.

Claims (1)

[Claims] 1. A fixed iron core 2 around which an excitation coil 3 is wound, a movable iron core 8 that is attracted to the fixed iron core 2, and the movable iron core 8.
In the electromagnetic breaker, the electromagnetic breaker is equipped with a movable rod 9 connected to the fixed contact 14 and having a movable contact 13 attached to the fixed contact 14 so as to be movable up and down. A connection spring 10 is installed between the movable iron core 8 and the movable rod 9, which are connected to each other in a state such that
and, provided on the movable rod 9, the fixed contact 14
a contact spring 15 that applies contact pressure to the movable contact 13 against the movable rod 9;
When the movable contact 13 rises while the movable rod 9 remains stationary due to the electromagnetic repulsion force that acts when an excessive current flows through both contacts of the fixed contact 14, the a latch fitting 16 having a hook portion 18 that engages with the engagement groove 17;
The latch fitting 16 is tilted against the biasing force of the latch spring 21 by colliding with a protrusion 20 provided at the tip of the latch fitting 16 and provided on the case 1 side when the movable rod 9 rises. a latch return piece 19 that releases the engagement between the engagement groove 17 and the hook portion 18 and lowers the movable contact 13;
and a trip coil 24 that is excited by an excessive current flowing through both contacts of the fixed contactor 14;
a catch arm 25 that tilts due to excitation of the catch arm 25; an arm 23 whose base end engages with the distal end engaging portion of the catch arm 25 in a non-tilted state, and whose distal end engages with the movable rod 9; It is provided between the arm 23 and the case 1, and is compressed when the arm 23 and the catch arm 25 are engaged, and when the engaged state is released by tilting the catch arm 25 due to excitation of the trip coil 24. a biasing spring 26 that applies a restoring force to the arm 23 and acts in a direction to separate the movable rod 9 from the movable iron core 8 against the biasing force of the connection spring 10; 25; and a reset handle 22 for returning the arm 23 to the engagement state with the catch arm 25. .