DE6921547U - ELECTROMAGNETIC TRIGGER - Google Patents

Description

The innovation relates to an electromagnetic release, in particular a fault current release with a permanent magnet and a triggering mechanism that influences the flux of the permanent magnet. Such triggers have the advantage of high sensitivity, i.e. that of the flux of the permanent magnet The armature that is held is caused to drop out even with the slightest excitation power on the release coil. The sensitivity combined with a high holding force of the armature, a small air gap between pole and armature, i.e. achieved by grinding the contact surfaces. In parallel with the high sensitivity, however, there is a disadvantageous one Susceptibility to failure due to external influences, / ie dust and water. They suffice for minor impurities the ground pole faces in order to influence the magnetic contact resistance to the armature so much that the required Holding force of the armature by the permanent magnet is no longer guaranteed. Around a defined air gap to obtain it is known to cover the pole face with a thin plastic film (DAS 1 271 831). but Even if this film is very thin, the total air gap is still relatively large, since the film is covered with an adhesive is applied. The shutter release therefore does not achieve its optimal sensitivity.

The task of the innovation is to design the pole faces in such a way that the air gap at the poles is a minimum, remains constant so that the disruptive pollution effect can not occur and the processing of the pole faces on a minimum · is reduced.

Pa: 4 <HS8. 2000 / EA)

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According to the innovation, therefore, to keep the Magnetic resistance between the pole and the armature of the pole and / or the armature surface coming to rest on the pole Applied with a thin, water- and dust-repellent covering made of plastic.

Polytetrafluoroethylene is expediently used for the covering, which is advantageously applied to the surface to be treated Surfaces is sprayed on, whereby a coating of the smallest thickness can be achieved. To get on the topping To push away sedentary dirt, this can be applied in narrow strips, so that the dirt particles slide sideways and evade. For the same purpose, the covering can also be perforated or form a grid.

Exemplary embodiments of the innovation are shown in FIGS.

! The release consists of a permanent magnet, the ones that are in contact with it Pole legs 2, the pole 3 of which holds the armature 4 loaded by the spring 5 after it has been pressed. A transverse bar 6 connecting the pole legs 2 optionally forms a shunt to the permanent magnet 1 the pole legs 2 arranged trigger coils 7 are used Actuation of the trigger. By exciting the trigger coils 7, the flowing through the poles 3 in the armature 4 is and the magnetic flux exerting the permanent magnet 1, which applies the holding force, compensates or displaces and the armature 4 brought to fall. The holding force is of the size of the The permanent magnetic flux is determined by the poles 3 and is a function of the magnetic resistance. Since the latter is essentially through the air gap

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is formed at the poles 3 is a big change the holding force is given by dirt on the pole 3. In order to avoid this, there are 8 on the pole faces a covering 9 made of dirt and water-repellent plastic, such as polytetrafluoroethylene, is applied. This Coating 9 is expediently sprayed thinly onto the pole face 8 in order to maintain the advantageous, small air gap. So that self-cleaning of the pole face occurs, the coating 9, as in FIG. 4, is in the form of a strip or applied in any form of vice. Of course, a perforation can also be used for the same purpose, like in Pig. 5, serve.

When the armature 4 hits the pole 3, dirt on the contacting pole surfaces 8 can get into the existing gaps: ©: flow or be printed. In order to there is a guarantee that the air gap at pole 3 will remain largely constant, which will also reduce the response values of the shutter release is retained with repeated actuation. The covering 9 can itself both on a how to be arranged on both contacting pole faces. Through him you can, if necessary, on the grinding the pole faces are dispensed with.

Claims (3)

- 4 - 583/69 Protection claims 1. Electromagnetic release, in particular residual current release with a permanent magnet and a release winding that influences the flux of the permanent magnet, characterized in that the pole and / or the pole (3) to keep the magnetic resistance constant between pole (3) and armature (4) coming to rest anchor surface is covered with a thin water- and dust-repellent covering (9) made of plastic. / 2. Electromagnetic release according to claim 1, characterized in that the covering (9) polytetrafluoroethylene is sprayed onto the pole faces./ 3. Electromagnetic release according to claim 1 and 2, characterized in that the covering (9) in the form of strips (Fig.4) is applied to the pole faces. 4. Electromagnetic release according to claim 1 and 2, characterized in that the covering (9) has a perforation (Fig. 5) or detent, / PaI 4 F I (868.5000 / EA)