SK285089B6 - Armature for magnetic trigger mechanism - Google Patents

Abstract

An armature (10) for magnetic trigger mechanism (1), mainly for safety switches, is plain bearing in guiding case (6). The armature (10) is manufactured from magnetic material, preferably from magnetically soft material by shaping a metal strip into a sleeve. The trigger plunger (14) is placed inside the armature (10), on which a return spring (16) is overthrust. The front end (17) of the return spring (16) is in touch with stopper of the trigger mechanism, which keeps the trigger plunger (14) in standby state. The armature (10) has in its end (11) a stopper in shape of a tongue (12), which is in touch with the end (13) of the trigger plunger (14).

Description

Technical field

BACKGROUND OF THE INVENTION The present invention relates to an anchor for actuating the trigger lifter of a magnetic trip mechanism for protective switches, which is formed by a sleeve formed from a sheet metal strip and has a stop for carrying the trigger lifter.

BACKGROUND OF THE INVENTION

Nowadays, anchors in magnetic trip mechanisms for protective switches are mainly produced by chip removal. This is not only a time-consuming and cost-intensive method of production, coupled with substantial material losses, but the anchors thus produced for the magnetic tripping mechanism have a relatively large weight which adversely affects the reaction time of the magnetic tripping mechanism fitted with such anchor.

An anchor of this kind is known from DE 25 31 215 A. In this known anchor formed by rolling the sheet metal strip, its edges do not abut one another. In addition, the stop for carrying the trigger lift to the anchor is formed by a recess into which the anchor lift engages. A disadvantage of this known anchor is that the ends of the anchor sheet surfaces extending in the direction of its movement form an anchor gap and are spaced apart from each other so that the eddy currents are reduced. Such an air gap anchor is not suitable for the magnetic cut-off mechanism, as shown by experiments.

SUMMARY OF THE INVENTION

SUMMARY OF THE INVENTION It is an object of the present invention to provide an easy-to-manufacture and function-enhanced anchor for a magnetic trip mechanism for protective switches.

According to the invention, this object is achieved by the edges of the metal strip directed parallel to the anchor axis, at least in given areas, abutting one another and that the reference to the tripping hoist is formed by at least one tongue formed integrally with the anchor directed perpendicular to the anchor axis .

Advantageous embodiments of the armature for the magnetic trip mechanism according to the invention are the subject of the subclaims.

The anchor for the magnetic breaking mechanism according to the invention can be produced not only by shaping, for example, by rolling the sheet metal at the cut or by punching from the plate, but also allows the fact that the anchor has a slight weight compared to the anchors used hitherto. This advantage is made possible by the aforementioned flush-free machining. Moreover, it has surprisingly been shown that the anchor according to the invention is also so advantageous that no magnetic properties of the anchor adversely affect the air gap, since the edges of the sheet metal strip, wound to form the anchor, abut against each other at least in regions.

The anchor tongue according to the invention, which serves as a gripper for the tripping hoist, allows a simple hoist construction which does not require any shaping, as is the case with the hoist according to the known embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS

Further advantages, features and details of the invention are set forth below with reference to the accompanying drawing.

In FIG. 1 shows a magnetic tripping device in a front view.

In FIG. 2 is a partial cross-sectional view of a magnetic tripping device without a guide sleeve, anchor and a trip jack.

In FIG. 3, a structural unit consisting of a guide sleeve, an anchor according to the invention, a trip jack and a return spring is shown partly in section and on an enlarged scale.

In FIG. Figures 4, 5 and 6 show a partial section of the anchor according to the invention.

In FIG. 7 shows another embodiment of the anchor according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

In FIG. 1 shows the magnetic trip mechanism 1 of a known construction used in line protective switches. It consists of a yoke 2 of a magnetic material, to which the carrier 4 of the fixed contact 3 of the protective switch, which is made of an electrically conductive material, is connected. Furthermore, the magnetic trip mechanism 1 has an excitation winding 5, which is electrically connected to the protected line by means of terminals (not shown). Inside the coil 5, the guide sleeve 6 is usually made of plastic, which is slid onto the sleeve-shaped stop 7 connected to the yoke 2 of the magnetic trip mechanism 1. For example, this sleeve-shaped stop 7 is connected to the yoke 2 and the carrier 4 of an electrically conductive material, whereby at the same time a connection is made between the electrically conductive carrier 4, which carries a firm contact 3 and with the yoke 2.

In the guide sleeve 6 there is a sliding, displaceably arranged anchor 10 of magnetic material which, at its end 11, facing away from the sleeve-shaped stop 7, has an inwardly projecting stop which is formed by a tongue 12 in the embodiment. the end 13 of the tripping jack 14 engages the tapered front part 15 of the tripping jack 14 with a return spring 16 which, with its front end 17, engages the end 18 of the bushing 7 which is inside the magnetic trip mechanism 1 and holds the trip jack 14 its standby position shown in FIG. Third

In the case of equipment, when the magnetic field created by the winding of the coil 5 is sufficiently large, the anchor 10 is tightened in FIG. 1, and carries by means of its tongue 12 a lifting jack 14, so that it, with its front end 19, actuates a trip mechanism (not shown) which, for example, is lifted in a known manner from the fixed contact 3 so that the protective switch interrupts the circuit.

The armature 10 used in the magnetic cut-off mechanism 1 according to the invention or in a magnetic cut-off mechanism of similar construction consists as shown in FIG. 4, 5 and 6, of an embossed sheet portion substantially in the form of a rectangle which is rolled in the form of a ring or sleeve. In this case, the embossed (sometimes also referred to as " spun ") part is wound into the ring or sleeve such that the edges 20, directed parallel to the axis of the armature 10, abut against each other and there is little or no contact air gap. In order to ensure that the edges 20 of the sheet metal formed into the anchor 10 parallel to the axis of the anchor 10 are closely aligned with each other, these sheet metal edges can be folded in advance in the sheet metal anchor production, so that at least the regions close closely to each other and there is no air gap that adversely affects the magnetic properties of the anchor.

In order for the trigger lifter 14 to be carried inside the armature 10 to be carried together when the armature 10 is moved, at least one radially inwardly angled tongue 12 is provided which is formed from one piece of metal with the metal part forming the armature 10.

On both sides of the rectangular bent tongue location 25, cutouts 26 are formed so that the tongue location 25 can be bent so that the tongue 12 extending perpendicular to the axis of the armature 10 does not extend beyond the adjacent end surface 27 of the armature 10.

When the anchor 10 shown in FIG. 5, the edges 20 abut each other with their entire surface. This can be achieved, for example, simply by placing these edges 20 at the manufacturing stage by embossing the sheet metal part at an angle to the plane of the sheet metal part not yet unwound. In this position, the air gap in the region of the contact point 21 is practically zero.

When the anchor 10 of FIG. 7, the edges 20 face each other at a small acute angle and abut against each other only in the region of their inner edges 28. However, the air gap in the region of the contact point 20 is so small that the desired magnetic properties of the armature 10 do not adversely affect it.

In particular, magnetically soft materials such as are known for direct current relays have proven to be advantageous.

The magnetically soft materials used have a saturation of 1.4 to 2 T at a field size of 4000A / m. A particularly preferred material for the anchor 10 of the invention is a material according to DIN 17 405 of October 1979 with Rfe80 (material number 1.1014) having a saturation of 1.6 T at a field size of 4000A / m.

In principle, any magnetic material is suitable as the material for the anchor.

In conclusion, the following exemplary embodiment of the invention can be described:

The armature 10 for the magnetic cut-off device 1 for protective line switches consists of a sheet metal strip shaped into a sleeve with a circular cross-section, the edges of which extend parallel to the axis of the armature 10 at least in areas close to each other. The stopper of the pick-up hoist 14, formed in one piece with the metal strip as the tongue 12, directed perpendicularly to the axis of the armature 10. In order to keep the air gap in the region of the contact point 21 of the housing as small as possible flat on each other.

Claims (12)

PATENT CLAIMS An anchor for a magnetic cut-off mechanism for a protective switch, consisting of a sheet metal strip formed into a housing and having a stop for carrying a tripping hoist, characterized in that the sheet metal strip edges (20) parallel to the axis of the anchor (10) closely abut each other in at least a few areas and that the reference to the tripping jack (14) is formed by at least one tongue (12) integral with the armature (10) perpendicular to the armature axis (10). Anchor according to claim 1, characterized in that the sheet metal strip is wound into a sleeve with a circular cross-section. Anchor according to claim 1 or 2, characterized in that the tongue (12) forms a right angle with the wall of the anchor (10) and is bent inwards. Anchor according to one of claims 1 to 3, characterized in that the location (25) of the tongue (12) lying in the wall of the anchor (10) has cut-outs (26) formed on both sides. Anchor according to any one of claims 1 to 4, characterized in that the tongue (12) is arranged inside an adjacent end surface (27) of the housing forming the anchor (10). Anchor according to claim 5, characterized in that the outer surface of the tongue (12) is flush with the adjacent end surface (22) of the anchor (10). Anchor according to any one of claims 1 to 5, characterized in that the edges of the sheet metal strip from which the anchor (10) is formed are in contact with each other in the region of the contact point (21) of the anchor (10). Anchor according to claim 7, characterized in that the narrow surfaces of the sheet metal strip are aligned obliquely to the plane of the sheet metal strip in the region of the edges (20) with the sheet metal strip still planar. Anchor according to any one of claims 1 to 6, characterized in that the edges (20) of the metal strip formed into the anchor (10) abut one another in the region of the anchorage point (21) with their inner edges (28). Anchor according to claim 8, characterized in that the narrow surfaces of the sheet metal strip are normally aligned with the plane of the sheet metal strip in the region of the edges (20) with the sheet metal strip still planar. Anchor according to any one of claims 1 to 10, characterized in that the anchor (10) consists of a magnetically soft material with a magnetic saturation of 1.64 to 2.0 T, preferably 1.6 T at a field size of 4000A / m. Anchor according to any one of claims 1 to 11, characterized in that the anchor (10) consists of the material Rfe80 according to DIN 17 405.