JPH0650964Y2 - Electromagnetic device - Google Patents

Description

[Detailed description of the device] [Industrial applications]

The present invention mainly relates to an electromagnet device used for a circuit breaker for wiring.

[Prior art]

In the case of a circuit breaker for wiring, when an overcurrent of several times the rated current flows or a short-circuit current of several tens of times the rated current or more flows, the overcurrent or short-circuit current is detected and the circuit shuts off. Need to be able to. An electromagnet device has been used as a current detection device for detecting an overcurrent or a short-circuit current. The electromagnet device includes an iron core around which a coil is wound, one end of the iron core is coupled to one end of the yoke, and the other end of the yoke is separated from the other end of the iron core. The other end is pivotally attached to a yoke that separates and contacts. Further, the armature is biased by the return spring in the direction of being separated from the iron core. Therefore, if the coil is inserted in the electric path, the armature is attracted to the iron core against the spring force of the return spring when an overcurrent or a short-circuit current passes through the coil.

[Problems to be solved by the device]

By the way, in such an electromagnet device, when the coil is excited, an attractive force also acts between the yoke and the armature. Therefore, when a short-circuit current or the like flows through the coil and the attractive force becomes very large, The frictional force between the armature and the armature cannot be neglected, which hinders the armature from swinging. That is, when the current applied to the coil is very large,
There is a problem that the oscillator becomes difficult to move and the responsiveness deteriorates. The present invention is intended to solve the above problems, and a non-magnetic material plate is provided on the contact surface between the yoke and the armature to weaken the attractive force between the yoke and the armature, It is an object of the present invention to provide an electromagnet device in which an armature can smoothly oscillate even when a very large current flows.

[Means for Solving the Problems]

In the present invention, in order to achieve the above object, a non-magnetic material plate is interposed on the contact surface between the yoke and the armature.

[Action]

According to the above configuration, the nonmagnetic plate interposed between the yoke and the armature allows the yoke and the armature to be separated from each other by a certain distance, so that the yoke and the armature are attracted. Since the force can be reduced, the frictional force between the yoke and the armature can be reduced and the armature can be swung smoothly.

[Embodiment 1] As shown in FIG. 1, a head 1a is formed in a flat disk shape, and a cylindrical shaft portion 1b having a smaller diameter than the head 1a is a head 1a.
The coil 2 is wound around the shaft portion 1b below the head portion 1a. The iron core 1 consists of an oil dash pot, and the shaft 1b has a head inside.
1a, a movable iron core that is vertically movable and has a variable distance between the fixed iron core and the lower end of the fixed iron core, and urges the movable iron core downward to separate it from the fixed iron core. It has a well-known structure in which a spring is provided and oil for braking the movement of the movable iron core is enclosed. A yoke 3 is coupled to the shaft portion 1b of the iron core 1 below the portion around which the coil 2 is wound. The yoke 3 is formed in a substantially L shape in which the vertical piece 3b rises upward from one end of the horizontal piece 3a connected to the iron core 1. Is provided so as to be spaced apart from each other and project upward, and a pivot support piece 5 is provided so as to project upward between both contact pieces 4. The contact piece 4 and the pivot support piece 5 are substantially parallel to the iron core 1, but the pivot support piece 5 is larger than the contact piece 4 in the iron core 1.
It is provided near the door. An armature 6 is attached to the upper end of the yoke 3.
Is pivotally attached. That is, the pivotally supporting piece 5 is loosely fitted to one end of the armature 6, and the sliding contact piece 6a bent downward is formed at one end of the armature 6, and the sliding contact piece 6a The curved portion contacts the contact piece 4. Therefore, the armature 6 swings up and down about the pivotal support piece 5 while sliding the sliding contact piece 6a on the contact piece 4. That is, a part of the armature 6 faces the head portion 1a of the iron core 1, and swings between a position in contact with the iron core 1 and a position away from the iron core 1. At the sliding contact portion between the contact piece 4 of the yoke 3 and the armature 6, a nonmagnetic plate 11 is fixed to the armature 6. By providing such a non-magnetic plate 11, when the coil 2 is energized, the armature 6 and the yoke 3 are
The attraction force acting between the yoke 3 and
The frictional force between the armature 6 and the armature 6 is reduced, and the armature 6 swings smoothly. A spring stop piece 6b is cut and raised at the tip of the armature 6, and a return spring 7 made of a coil spring is installed between the pivot support piece 5 and the spring stop piece 6b.
The armature 6 is biased in a direction in which it is pulled away from the iron core 1.
The return spring 7 is covered with a flexible tube 8. Therefore, it is possible to prevent the armature 6 from being caught when the return spring 7 expands and contracts. The terminal plate 9 is connected to one end of the coil 2 described above, and the connecting wire 10 made of a braided wire is connected to the other end. According to the above configuration, when the coil 2 is energized with a current that attracts the movable iron core in the iron core 1, the distance between the movable iron core and the fixed iron core becomes small, and the iron core 1, the yoke 3, and the contact point. The magnetic resistance of the magnetic circuit composed of the pole piece 6 is reduced, the attraction force acting on the armature 6 from the iron core 1 is increased, and the armature 6 is attracted to the iron core 1. The armature 6 is not attracted as long as the current applied to the coil 2 does not move the movable iron core. An example in which the above-mentioned electromagnet device A is used in a three-pole type circuit breaker for wiring is shown in FIGS. 2 and 3. The body 20 is formed in a box shape by combining a base 21 and a cover 22 made of synthetic resin. An electric path is formed between terminals 23a and 23b provided at both ends of the body 20 in the longitudinal direction, and the electromagnet device A and the contact portion 25 are inserted in series in each electric path. That is, one electromagnet device A is provided for each pole, and a total of three electromagnet devices A are provided. The one terminal 23a is a screw terminal in which the terminal screw 24 is screwed into the terminal plate 9 described above, and is connected to the power source side. Further, the other terminal 23b is also a screw terminal provided with a terminal screw 24 and is connected to the load side. The tip end of the armature 6 of the electromagnet device A faces the trip piece 31 of the trip mechanism portion 30. The trip mechanism section 30 holds a large number of links and springs by a frame 32, and is connected to a movable contact 26 that constitutes a contact section 25. The movable contact 26 is connected to the coil 2 via the connection wire 10 and is provided with the movable contact 26a, and the fixed contact 27a facing the movable contact 26a is the terminal plate 27 constituting the load side terminal 23b. It is provided in. Further, the interlocking rod 28 is arranged so as to straddle the movable contacts 26 of the respective poles, and when any one movable contact 26a of the movable contacts 26 of the three poles is separated from the fixed contact 27a, The interlocking rod 28 rotates so that the movable contact 26 of the other pole also separates the movable contact 26a from the fixed contact 27a. The trip mechanism portion 30 brings the movable contact 26a into contact with the fixed contact 27a by closing the handle 33 protruding from the body 20 to the upper side in FIG. 2 to close the contact portion 25, and at this time, the contact portion 25 It is configured to be held in a state in which the spring force in the direction of opening the electrode is accumulated. In this state, tilt the handle 33 downward in Fig. 2 or pull it out.
By pushing 31 to the left side in FIG. 2, the contact is released, the spring force is released, and the contact portion 25 is rapidly opened. Therefore, when the armature 6 is attracted by the iron core 1 and the tripping piece 31 is pushed to the left side in FIG. 2 with the handle 33 tilted upward as shown in FIG. 2, the contact portion 25 opens. Therefore, when the contact portion 25 of any one of the three poles is opened, the contact portion 25 of the other pole is also opened. That is, when the overcurrent continues to be applied to the coil 2, the movable iron core in the iron core 1 approaches the fixed iron core while being braked by oil, and when the distance between the fixed iron core and the movable iron core becomes small to some extent, the contact occurs. The pole 6 is attracted to the iron core 1. When a short-circuit current is applied to the coil 2, the magnetic flux passing through the head 1a of the iron core 1 increases regardless of the movement of the movable iron core, so that the armature 6 is attracted. When the overcurrent flows for a short time, the distance between the movable iron core and the fixed iron core is not sufficiently reduced, so that the armature 6 is not attracted to the iron core 1. In this way, the electromagnet device A does not respond to a short-time overcurrent, but opens the contact portion 25 in response to a long-time overcurrent and short-circuit current.

Second Embodiment In this embodiment, as shown in FIG. 4, instead of fixing the non-magnetic material plate 11 to the armature 6, the non-magnetic material plate 11 is fixed to the contact piece 4 of the yoke 3. The other configuration is the first embodiment.
Is the same as. With this configuration, the same effect as that of the first embodiment can be obtained.

[Effect of device]

As described above, the present invention has a non-magnetic material plate interposed on the contact surface between the yoke and the armature. Due to the presence of the non-magnetic material plate, the yoke and the armature are separated by a certain distance. Since they can be separated from each other and the attraction force between the yoke and the armature can be reduced, the frictional force between the yoke and the armature can be reduced and the armature can be swung smoothly. Have advantages.

[Brief description of drawings]

FIG. 1 is a perspective view showing a first embodiment of the present invention, FIG. 2 is a sectional view showing an example of a wiring breaker using the same as above, and FIG. 3 is an example of a wiring breaker using the same as above. Partially cutaway front view,
FIG. 4 is a perspective view showing a second embodiment of the present invention. 1 ... iron core, 2 ... coil, 3 ... yoke, 6 ... armature, 7 ... return spring, 11 ... non-magnetic plate.

Claims (1)

[Scope of utility model registration request] 1. An iron core around which a coil is wound, a yoke whose one end is magnetically coupled to one end of the iron core and the other end of which is desired near the other end surface of the iron core, and The yoke and the armature are provided with an armature facing the other end surface and pivotally attached to the other end portion of the yoke, and a return spring for biasing the armature from the other end surface of the iron core in a direction in which the armature pulls out. An electromagnet device having a non-magnetic plate interposed on its surface.