DE2204041A1 - Electromagnet, in particular for driving electrical switching devices - Google Patents

Description

Electromagnet, in particular for driving electrical switching devices

The invention relates to an electromagnet, in particular for driving electrical switchgear, with relatively movable core and armature parts, which parts have pile flecks hitting one another when a winding attached to them is excited.

For driving electromagnetic switching devices, e.g. contactors Electromagnets generally provided with E- or LJ-shaped iron cores used. To prevent an electromagnet from sticking To prevent this, a remanent air gap is required in the magnetic circuit. In most cases of E-cores, this remanent air gap is between the middle leg of the Ε-core and the armature arranged. The life of such an electromagnet depends on Retentive air gap. If the clashing pole faces on the Anchor and on the two side legs of the Ε-core by the. Frequent If the anchor is struck, the re- | disappears manent air gap between the armature and the middle leg of the Ε core and the contactor can stick.

Various names are known to ensure that a Ε core does not stick until after a high number of operations. The best known measure for increasing the number of operations until an electromagnet with a Ε core sticks is oiling the cores. P278

2098 * 9/0814

220404V

Through the delenation of the cores you can reach a non-oiled one Core about 10 to 15 times the number of operations - until it sticks. This measure is nevertheless unsatisfactory because the oils available today can, on the one hand, crawl onto the contacts where they are cause poor contact reliability and, on the other hand, resinify and dry up, which increases the number of switching operations and increases the lubricating and damping effect of the oil and thus the mechanical service life of the electromagnet is greatly reduced.

It is also known to encapsulate magnetic cores of electrical apparatus in their housing with a casting resin. The resin fills in the process also remove the gaps between the individual sheets of the electromagnet. These electromagnets are in terms of lifespan slightly better than dry, untreated core. The number of cycles of these electromagnets until they stick are about twice that of the dry and untreated kernels. With the help of this solution, the life of the treated with OeI can be increased Core cannot be reached.

For increasing the number of operations until an electromagnet sticks is known to use a dry lubricant on the pole faces, e.g. to supply molybdenum disulphide. The dry lubricant is placed between the metal sheets of the core or in one of the magnet bodies surrounding porous body stored. Tests have shown that the life of using a dry lubricant supply executed cores is far below that of the oiled cores.

The object of the invention is to find a solution to the service life an open electromagnet with an unlubricated electromagnet to achieve and to surpass.

The problem posed is achieved in that at least one of two mutually hitting pole faces with at least one with Plastic-filled recess is provided and the surface of the plastic embedded in the recess is flush with the pole face is.

209849 / OIU

220404t

Tests have shown that it is fitted flush with the pole face Due to its lubricating and steaming effect, plastic extends the service life of an electromagnet compared to an untreated core increased by a factor of 10 to 20. The plastic is distributed through the collision of the pole faces like a film on the entire pole face.

As plastic, epoxy resin, polyester., Polyurethane resin or another plastic can be used.

A further increase in the service life is possible by going to Plastic mixed with a dry lubricant. For example, flolybdenum disulphide can be used as a dry lubricant.

The invention is described in more detail below with reference to the accompanying drawing. Show it:

1 shows a Ε core in side view,

Fig. 2 shows the same Ε core in plan view, Fig. 3 shows one pole face of an E core, 4 and 5 individual sheet metal parts.

In Fig. 1 is the side view of an E-shaped sheet iron core 1 shown. The two side legs 2 are provided with short-circuit rings 4 on the pole faces 3 to prevent the electromagnet from humming to diminish. The armature, not shown in Fig. 1, is when a not shown, the middle leg is excited 5 surrounding winding on the pole faces 3 of the two side legs on. A remanence air gap is arranged between the armature and the pole face 6 of the middle leg 5 in order to prevent it from sticking to prevent the electromagnet.

The short-circuit rings 4 are in the two side legs 2 inserted grooves. The recesses 7 present between the short-circuit ring 4 * and the plane of the pole face 3 are with filled with a plastic. The surface of the recess

209849/061 A BAD ORIGINAL

22040U

gen 7 embedded plastic is flush with the pole face 3. When the poles are hit repeatedly, the plastic becomes from the recesses 7 more and more to those made of iron Part of the pole face 3, where a plastic film is created. The plastic film prevents by its lubricating and dampening effect rapid wear of the pole surfaces 3 and prolonged thereby the lifespan of the electrical system.

In FIG. 3, one pole face β of a core S is in the shape of a scliach ^ rstt distributed recesses 10 shown. The recesses IG are punched into the individual sheets 11 and 12 of the core 9, see Fig. 4 and Fig. 5. There can also be several r.it at the same place attached recesses lü provided Bische 31 or 12 r.eb; be arranged nander. The short-circuit ring 4 in Fig. 3 is like ir 1 and 2 fastened in the core 9. The exceptions £ n 7 ~ '10 are with filled with a plastic.

The pole face of the arrangement according to FIGS. 3, 4 and 5 is enlarged by the area occupied by the recesses 10 and 7. For this purpose, the plates 11 and 12 are in! Abruptness of PoIf3.sch ·. · Ü wider. This arrangement is particularly advantageous because the larger impact area dia specifically- ;; kinetic energy of impact is reduced, which contributes to an increase in the voltage, and because the induction at the pole face 8 is not increased by the design 7 and 10, so that the holding ampere-turns of the electromagnet is not increased.

BATH ORIGINAL 209849 / 06U «

Claims (6)

_ 5 -. Patent claims ι 1. MeKtroniagnet, especially for driving electric ochaitge. ate, with core and anu that are relatively movable to one another. it parts which, when a winding attached to them is excited, have pole faces hitting one another, characterized in that at least one of every two pole faces hitting one another is provided with at least one recess (7, 10) filled with plastic and the surface of the in the recess (7, 10) of the embedded plastic is flush with the poly (3, <i). 2. Electromagnet according to claim 1, characterized in that the pole face (8) around the through the recesses (7, 1ü) stressed area is increased. 3. ürlektromagnet according to claim 1 or 2, characterized in that the recesses (10) on the pole face (B) Are arranged in a checkerboard shape. 4. üilektromagnet according to claim 1 or 2, characterized in that the recesses (7) in the pole face (3 »β) are attached in the form of parallel channels. 5. Klektromagnet according to claim 1, characterized gekennaichnet, that the plastic is epoxy. 6. electromagnet according to claim 1, characterized in that that the plastic is Poly ti: Ut /. Electromagnet according to claim i, characterized in that that the plastic is polyurethane resin. 209849 / Ü6U ™ * Ο ~ " ö, iiLektroaafcßet according to an egg ıiis saying b to 7 »üa üurcii ^ ekenü denotes that the plastic contains a filler. 'J. ü / leK.trüia% iiet; acii claim, characterized in that the filler is a drying agent, for example i'iolybdenum sulphide. 2Π9849 / 061 U