DE1092104B - Lifting anchor of a contactor guided in several points - Google Patents

Description

Three-phase air contactor for small and medium currents up to about 200 Amp. Current ratings are becoming more recent At that time it was made almost exclusively with contact pieces made of precious metal, predominantly silver. Sagittarius with silver contacts require a straight parallel movement during the switch-on process the moving contact pieces. As a rule, this is achieved in that the movable contact arrangement with the movable part of the magnet, the Magnet armature, is firmly connected, the armature being assigned a parallel movement.

Three-phase air contactors for rated currents above 200 Amp., On the other hand, are still almost exclusively with Equipped with copper contacts. To actuate the contact arrangement, the so-called Folding armature magnet has become a permanent fixture. This magnet has a fixed axis around which the magnet armature is pivoted. Such an axis inevitably results in an exact guidance even for the right large magnet armature large air gunner. The precise guidance of the armature is of great influence on the mechanical life of the magnet. The pole faces are protected the better, ever larger is the area with which the magnet halves touch when they hit. Thanks to its precise guidance When it hits the hinged armature, it inevitably carries the entire pole face; the specific load is therefore a minimum.

In addition to the undoubted advantages of the Cu contacts, especially for air contactors with high rated currents, Cu contacts have the disadvantage that the contact life measured in switching operations is unsatisfactory is. Contact pieces made of Ag compounds result in a level that is almost an order of magnitude higher Contact life.

There is therefore a desire also for larger air guns, and in particular those for very frequent switching and for a mechanical service life of 10 million switching cycles and more, To be able to use silver contact pieces, but for which, as mentioned above, a parallel movement of the Contact arrangement is required. The invention is therefore based on the object of a contactor for to create large switching capacity and silver contact pieces.

The exact guidance of the magnet armature then necessary is with large magnets with parallel moving Anchors pose a difficult problem, however. The main difficulty is that when you hit it of the armature the pole faces do not necessarily come into contact with their entire surface, as is the case with hinged armature magnets. Depending on the goodness of the leadership takes place with the known Anchoring with parallel movement the first contact. Lifting anchor guided in several points of a contactor

Applicant:

Siemens-Schuckertwerke

Corporation,

Berlin and Erlangen,

Erlangen, Werner-von-Siemens-Str. 50

Dipl.-Ing. Gustav Wilhelm Pristsak, Berlin-Spandau, has been named as the inventor

only on one of the four outer edges or even only on one of the four outer corners, less often on the whole Pole face instead. This means that the two poles are very sharp when you touch them for the first time Form an angle, the tip of which is at the contact edge. Job of a good mechanical Leadership is to bring this angle as close as possible to the value 0, this is the case when the pole faces hit parallel.

It is already known to guide lifting anchors in several points, two of these guides in close to the pole face and the third as far away from it as possible. These tours are relatively loose in the known lifting armature magnets and do not meet the requirements, that of larger air shooters due to the relatively high impact loads they need to be asked. Even with small tilts in the armature, these guides are used when Impact of the armature on the magnetic core quickly knocked out, so that the life of such magnets is only slight.

On the other hand, if you make the game in the guides very small in order to ensure that the To force pole faces, it is to be expected that the pole faces are also in the switched-on state only touch along one edge. If it is also following the first touch to close the Pole faces come, so a full closing does not take place, and the magnet hums; the system is statically overdetermined. The static overdetermination arises from the fact that the leadership on the anchor prevents full resting.

009 630/319

In the case of a lifting armature of a contactor that is guided in several points, according to the invention with the best possible sliding properties of the guide surfaces, the guide tolerance is as low as possible held and released shortly before the anchor hit the leadership causing overdetermination.

In the drawing, an embodiment of a magnet according to the invention is partially cut in two Views shown.

The upper part of the magnet is firmly mounted in the housing 1, underneath the armature body, which is composed of the laminated core 3 'and a support body 3 ″ Pin 5 guided on the lower part of the support body 3 ". These three guides lie in a common plane of symmetry of the armature lying parallel to the metal sheets of the sheet metal body in the direction of movement of the armature. According to the invention, a bushing 6 is used for guiding the pin 5, which has a hard, smooth surface with the lowest possible guiding tolerances, the dimensions and arrangement of the bushing being such that, as indicated by dashed lines in FIG an overdetermination of the leadership when the armature impinges significant leadership 5, 6 shortly before it meets on the upper magnet part 2 is solved.

Claims (1)

Claim: ίο One lifting anchor guided in several points Contactor for large switching capacity with silver contact pieces, characterized in that with as possible good sliding properties of the guide surfaces the guide tolerance as low as possible hold and that shortly before the anchor hits the one causing overdetermination Guide (5, 6) is released. Considered publications:
German patents No. 748 549, 943 421,
812; U.S. Patent No. 2,459,078. 1 sheet of drawings