JPH0510330Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to an electromagnet used in relays and the like.
More specifically, it relates to hinged electromagnets.

[Background technology]

Conventionally, relays using this type of hinge-type electromagnet tended to have low open circuit voltages, and there was a risk of reset failure depending on the load on the electromagnet and other conditions, so a return spring was used to provide the reset force. The necessary restoring force was obtained by increasing the voltage, but as a result, the sensing voltage also increased, making it difficult to operate at high sensitivity. Furthermore, if the return spring is strengthened, the hinge portion will be worn severely during opening and closing, and as the number of openings and closings increases, the characteristics will become unstable.

[Purpose of invention]

In view of the above-mentioned circumstances, the present invention provides an electromagnet that can increase the return force without increasing the attraction force in order to obtain a relay with stable operation and no return failure.

[Disclosure of invention]

The present invention includes a yoke to which an iron core is attached together with a coil frame, and an armature having a base end engaged with one end of the yoke, a free end facing the head of the iron core, and equipped with a return spring. In the electromagnet having the above, when the armature is attracted to the iron core between one end of the yoke that engages the base end of the armature and the head of the iron core, a magnetic gap is created at the engaging portion between the yoke and the armature. The device is characterized in that a second fulcrum is provided, and the second fulcrum makes it possible to increase the return force without increasing the suction force.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

In FIG. 1a, 1 is a yoke which hinge-engages the proximal end 5b of the armature 5 to one end 1b extending parallel to the coil 3 wound around the coil frame 2, and also connects the proximal end 5b of the armature 5 to one end 1b extending parallel to the coil 3 wound around the coil frame 2. The proximal end 4a of the iron core 4, through which the coil frame 2 is inserted, is attached to the other end 1a which is bent parallel to the portion 2a, so that the overall shape is approximately L-shaped. Further, a protrusion 1c extending in the opposite direction to the one end 1a of the yoke 1 is provided in the middle of the other end 1b of the yoke 1, and the protrusion 1c extends between the protrusion 1c and the proximal end 5b of the armature 5.
In between is a return spring 6 that provides a return force to the amateur 5.
is mounted. One side of the free end 5a of the armature 5 faces the head 4b of the iron core 4.

Between one end 1b of the yoke 1 hinged to the base end 5b of the armature 5 and the head 4b of the iron core 4, when the armature 5 is attracted to the iron core 4 and moves, the one end 1b of the yoke 1 A protrusion 10 is provided to create a magnetic gap between the armature 5 and the proximal end 5b of the armature 5. The iron core 4 and the yoke 1 are composed of one approximately U-shaped yoke, and the one leg is connected to the coil frame 2.
The iron core 4 may be inserted into the iron core 4.

When the current flowing through the coil 3 is gradually increased and the attraction force curve of the magnetomotive force shown in FIG. 2 becomes larger than the spring load curve L and becomes curve A, point A
At point A2, the armature 5 is attracted to the iron core 4 and begins to move, and at point A2, the armature 5 comes into contact with the protrusion 10. As the suction continues and the movement progresses, the proximal end 5b of the armature 5 is moved to the one end 1b of the yoke 1, as shown in Figure b.
As they move further apart, a magnetic gap G is formed between them. With this magnetic gap G increasing the magnetic resistance of the magnetic circuit and reducing the magnetomotive force, the free end 5a of the armature 5 comes into contact with the head 4b of the yoke 1 at point A3. Next, as the current is gradually decreased, the attraction force curve becomes lower than the spring load curve L and reaches curve B. From point B1, the return force of the return spring 6 becomes greater than the attraction force, so the armature 5
The free end 5a of the yoke 1 begins to separate from the head 4b of the yoke 1 and quickly returns to its original position. In this case, conventionally, the armature 5 would not return unless the magnetomotive force was lowered to curve c, that is, the current was reduced, but by providing this protrusion 10, conventionally the armature 5 would be at point D and would not be able to return. curve B
Since the armature 5 is restored by simply reducing the magnetomotive force to , it is possible to restore the current by reducing the rate at which the current is reduced. In other words, the returned magnetomotive force can be increased.

Note that the protrusion 10 is not limited to being provided on the collar portion 2b of the coil frame 2, and the armature 5 is provided on the iron core 4.
If a magnetic gap can be formed between the yoke 1 and the armature 5 when the armature 5 is attracted to the
There is no problem in forming a protrusion 10 extending to the collar portion 2b between the armatures 5 facing each other.

Furthermore, if the height of the protrusion 10 for forming the magnetic gap G is within this range, if the value at point A4 of the curve A4 is higher than the load curve L, the suction operation is stable. You can set it to any height you want.

[Effect of idea]

As described above, the present invention provides a second magnetic gap between one end of the yoke engaged with the base end of the armature and the head of the iron core, which creates a magnetic gap between the yoke and the armature when the armature is attracted to the iron core. By providing a fulcrum, the armature can be returned to normal position by a small decrease in magnetomotive force without increasing the attractive force, so if the electromagnet of this invention is used in a relay, only the open voltage can be reduced without increasing the impressed voltage. It is possible to obtain a relay with stable characteristics. Further, since it is not necessary to strengthen the return spring to increase the open circuit voltage, it is advantageous that the hinge part is less worn and the relay has a long opening/closing life.

[Brief explanation of the drawing]

1A and 1B show an embodiment of the present invention, in which FIG. 1A is a side view showing the state before excitation, and FIG. 1B is a side view showing the state during excitation. FIG. 2 is a suction force-stroke curve diagram illustrating the same operation as above. FIG. 3 is a side view of main parts showing another embodiment of the present invention. 1...Yoke, 1b...One end, 2...Coil frame, 4...Iron core, 4b...Head, 5...Armature, 5a...Free end, 5b...Proximal end, 6...
Return spring, 10...second fulcrum.

Claims (1)

[Claims for Utility Model Registration] (1) A yoke to which an iron core is attached together with a coil frame, a base end portion of which is engaged with one end of the yoke, and a free end portion of which is opposed to the head of the iron core and returned. In an electromagnet having an armature mounted with a spring, the engagement between the yoke and the armature is provided between one end of the yoke that engages the base end of the armature and the head of the iron core when the armature is attracted to the iron core. An electromagnet characterized by having a second fulcrum that creates a magnetic gap at the top of the electromagnet. (2) The electromagnet according to claim 1, wherein the second fulcrum is a projection protruding from the coil frame. (3) The electromagnet according to claim 1, wherein the second fulcrum is a protrusion provided on the armature.