DE3417891C1 - Electromagnetic switchgear - Google Patents

Description

The invention relates to an electromagnetic switching device, consisting of a magnetic drive with a permanent magnet assembly and a yoke surrounding a bobbin, the core hole of which is continuous contains a lifting armature which actuates a contact slide via deflection lever, which is parallel to the longitudinal axis of the bobbin is arranged displaceably and carries spring-loaded contact bridges, each of which is opposite at least two fixed contacts are assigned, the coil body having two spaced apart, each having a coil winding receiving chambers and the permanent magnet arrangement is symmetrical to the longitudinal axis of the bobbin between the two chambers, at right angles to The longitudinal axis of the bobbin is polarized and approximately the diameter of the core hole of the bobbin has a corresponding passage opening for the armature, which has a non-magnetic guide part and

an additional object of the invention, the parallelogram formed by lever, lifting armature and contact slide to make assemblable with the least possible assembly effort and with the least possible Bearing play to be maintained, if possible with a play-free parallelogram function.

This is achieved in detail with the measures specified in the subclaims.

The switching device is based on the drawings

F i g. 2 shows a section through the switching device according to line AA in FIG. 1;

F i g. 3 shows a section along the line BB in FIG. 1;

Fig. 4 the parallelogram with bearing pin, bearing of lifting armature and contact slide;

F i g. 5 shows a section through the lever and the contact slide according to the line CC in Fig. 1, the bearing point of the contact slide in the deflection

its two end faces with those in the area of the respective end-face openings of the core hole of the coil former lying pole faces of the yoke cooperate.

Such a switching device is in-house state of the art, as it is essentially in the DE-OS 32 30 564 is described.

Core pieces that are attached to the front sides of the
Coil-facing sides of the yokes of the magnet device are formed, there form the bearing point of the armature provided with io of the invention on a partially schematically combined guide rod. The embodiment illustrated in the box explained in more detail, clock slide, arranged above the magnetic device

net, is in a housing carrying the fixed contacts F i g. 1 is a plan view of the switching device, in which

slidably mounted. The movement of the magnet is cut open and with Welkers the reversing lever and the magnetic drive are carried out in the lever via two mutually symmetrical reversing levers, each of which is cut through in the middle; stanchions of the bobbin arranged pivot point
is rotatably mounted and with its one end
one end of the armature guide rod, with its other end in operative connection with the contact slide 20
stands. At the point of contact the reversing lever occurs
Both the guide rod and the contact slide have a friction path, the extent of which is determined by the circular movement of the reversing lever around its pivot point. The friction losses of the switching device 25 lever takes place in a groove with a central web; are thus determined by the anchor / core losses. 6 as in FIG. 5, but with the following lower part, then from the losses of the contact slide / housing: the contact slide is mounted in the reversing lever in a rectangular recess, from the losses reversing lever / guide rod, the contact slide from the losses reversing lever / contact slide and consists of two halves which are arranged to be slidable in the longitudinal axis from the losses of the reversing lever in its 30;

Depository. These losses are of several importance. 7 shows a section along line DD in FIG. 2;

tion: Once the magnetic drive has to be increased by the amount of F i g. 8 shows a section along the line EE in FIG. 2.

Losses are stronger and thus increase in volume. According to FIGS. 1, 2 and 3 is in the upper half

be guided. But the magnetic drive is arranged much more meaningfully in this representation, in the friction losses in a two-position operation of the lower half of the contact apparatus. Two U-shaped pole switchgear. There the danger increases that the yoke halves la and \ b are not bent and enclose a desired central position with the amount of friction losses. Coil body 2, which has between the middle coil flange, in order to make this type of switching device at 2a, 2b cube-shaped recesses, in two-position operation, must which two permanent magnets 3a, 3Zj are inserted. Both the shock resistance in the rest position of the 40-sided permanent magnets 3a, 3b extend the Spu switchgear or the value for lenwicklungen 4 and 5 (in Fig. 1 the coil windings are shown; in F i g. 2 and 3 each one of the connections 60 lying in a row one behind the other and routed through the housing 16). In the bore 6 extending through the bobbin 2, a lifting armature 7, consisting of a guide part 8 and armature plates 9, is introduced, the direction of movement of which runs parallel to the central axis of the bobbin 2. The lifting armature 7 is designed in three parts; Above and below one and the pole faces of the 50 magnetically neutral guide part 8 facing the lifting armature, permanent magnets and the resulting negative-conducting armature plates 9 are joined, the end faces of which have the effect of high armature bearing loads. the thigh surfaces facing the coil windings

This object is achieved according to the invention in that the yoke halves la, \ b form the working air gaps of the magnet system mounted in the housing of the switching device. The guide part 8 protrudes over the deflection lever on the front side of the 55 armature plates 9 facing the magnetic drive and ends in recess ends over the guide part carrying the lifting armature and gen 10a, 11a of the deflection lever 10 and 11, which are spatially defined, at the other ends of the Deflection bearing journals 12, 13 are rotatably mounted. Carry the contact slide on the other lever and also clear it, fix the end opposite the recesses 10a, 11a, and the deflecting lever together with that of the deflecting lever 10, 11 are further recesses lifting armature and the contact carrier in the manner of a fixed 60 106, Wb , in which formations 14a, 146 of the coupled parallelogram act. of the contact slide 14 intervene. The in contact

By means of these measures, a force shifter 14 is obtained on contact bridges 15 (FIGS. 1 and 3) bearing system, in which frictional losses as in 3) form together with those press-fitted in the housing 16 State of the art between the guided fixed contacts 17 (in FIG. 1 the contact is a soling part of the anchor and the core pieces as well as between 65; in Fig. 3 only the one from the case Contact slide and housing are created, 16 protruding connection pins prevent the contact systems. in the the will. Example shown in FIG. 1 are eight contact bridges

In pursuit of the inventive solution, 15 was created with two associated fixed contacts 17 each.

the minimum permissible switch-on pulse duration with a bistable function must be considerably higher. The consequence of this is a reduction in sensitivity and an increase in operating energy.

The invention is based on the object of creating a switching device of the type specified in the introduction, in which the friction losses are kept small and this also with eccentricities between the lifting armature

shows, of which four contact systems (e.g. the one shown on the far left), one contact system with normally open function, others four contact systems (e.g. the one shown on the far right) represent a contact system with a normally closed function.

The magnetic drive is used to switch from the contact position shown to the other switch position to excite so that in a known manner the magnetic flux direction of the coil windings 4 and 5 of the direction counteracts the permanent magnetic flux in the air gap 18, i.e. weakens until the coil magnetic flux predominates the flux of the coil windings 4, 5 and the permanent magnets 3 a, 36 is added in the air gap 19 and thus the armature 7 changes from the switching position shown to the other switching position, so the air gap 18 to the maximum and the air gap 19 to the minimum, the contact slide 14 over the two Deflection lever 10,11 moved into the other switching position will. To return the lifting armature 7 and thus also the contact slide 14 to the rest position shown the current flow in the coil windings is to be reversed in the bistable magnetic drive design, and the described switching process is repeated in reverse order. With monostable magnetic drive design the return to the rest position has to bring about a return spring (not shown), which after switching off the current flow in the coil windings 4, 5, the holding force of the permanent magnet has overcome.

The coupling points of the guide part 8 and the contact slide 14 with the reversing levers 10, 11 lead a circular movement around the pivot points while switching from one switch position to the other or pivot pins 12, 13, whereby the distances between the center line 8 * of the lifting armature 7 and the Center line 14λγ of the contact slide 14 with all Switching states of the electromagnetic switching device run parallel to one another, but differ in their distance change. To the movement of the lifting armature 7 in the bore 6 of the bobbin 2 free from To keep frictional losses, the distance 20 between the anchor plates 9 and the coil body 2 and the distance 21 of the guide part 8 to the end faces of the legs of the yoke halves 1 a, 16 optionally enlarged accordingly.

In most cases, however, the parallel shift is so small that it can be used when dimensioning the air gaps can be neglected. For example, this parallel shift is ± 0.03 mm for a Contact slide travel of 2 mm and a transmission ratio of the coupling point of the contact slide 14 to bearing pin 12, 13 and from here to the coupling point of the guide rod 8 of 12 mm 6 mm. Equally, it helps to eliminate frictional losses between the contact slide 14 and the housing 16 the dimensioning of the distances between the housing ribs 16a and the contact slide 14 to proceed.

In Fig. 2 shows the mounting of the reversing lever 10 on bearing journals 12. The journal 12 is either Injected together with the housing 16 from molded material, which is located in a blind hole 22 of the housing cap 23 is supported, or in the housing 16 as well as in the housing cap 23 a blind hole is formed, in which a bearing pin is inserted.

F i g. 3 shows the permanent magnets 3 a and 36, which are inserted into cubically shaped recesses in the bobbin 2. The stop of the permanent magnets on edge 2a of the bobbin 2 ensures that the distance 20 between the anchor plates 9 and the permanent magnets 3a, 3b is guaranteed. The yoke halves la and 16, which are supported in corresponding recesses 24 of the flanges of the coil body 2, hold the permanent magnets 3a, 3b inserted in the coil body 2 in their position. The pre-assembled “magnetic drive” package is inserted between the ribs 25, 26 of the housing 16 and, after the housing cap 23 has been pushed on, is held in the correct position, usually without additional aids. The intermediate insulating layer 27 is used for enlargement

ίο the creepage and air distances between the magnetic drive and the contact device. To seal the interior of the electromagnetic switching device, the sealing joint 28 between the housing 16 and the housing cap 23 and the connection openings 29 are filled with electrically insulating potting compound. The connections 17a of the fixed contacts and the connections 60 of the coils 4, 5 are passed through the housing 16 and held by the potting compound.
The lifting armature 7 according to FIG. 1 can now be designed with a rotationally symmetrical outer contour or square or rectangular as shown in section in FIG. The rotationally symmetrical outer contour has the advantage that the bearing point in the reversing levers is unproblematic. This advantage can best be used with a normal, ie non-polarized, magnetic drive. In the case of polarized drives, however, the surface of the permanent magnets 3a, 3b facing the lifting armature 7 would then have to have a circular arc contour, which causes additional costs. For polarized magnetic drives, it is therefore more economical to use the method shown in FIG. 3 to be preferred. If the prerequisites for the use of a rotationally symmetrical lifting armature are given, the parallelogram formed by the lifting armature, deflection lever and contact slide can preferably be designed with ideal coupling points according to FIG. 4. The coil winding 30 is enclosed by two yoke halves 31a and 316, in the central bore of which a lifting armature 32 is arranged, in which a guide rod 33 is inserted, which carries fork heads 34 at both ends. Two deflection levers 35 are rotatably mounted at 36 and connected to the armature 32 and the contact slide 38 via hinge pins 37.
As shown in FIG. 2 shows that the lifting armature 7 can be displaced in the direction of the longitudinal axis of the recess 10a, 11a or 106, 116 (this is to the left and to the right in FIG. 2) through the edge webs 39 of the deflection levers 10, 11 and the contact slide 14 the edge webs 40 prevented, the guide part 8 dipping in its full width into the recess 10a, 11a and thus the maximum possible protection against rotation of the lifting armature 7 about its center line Sx (see FIG. 1) is achieved. For the contact slide 14, this optimum security against rotation about its center line i4x (see FIG. 1) is achieved in that the recess 106, 116 (see FIG. 5) in the reversing levers 10, 11 has through grooves 41, 42 (see FIG. 5) is replaced, which are interrupted to limit the lateral displacement by central webs 43, 44 which engage in recesses 45, 46 of the deflection lever 10, 11.

From Fig. 5 shows the two-part design of the contact slide 14. The two-part version is necessary for inserting the contact bridges 15 in corresponding recesses in the contact slide 14. In each recess there are two contact bridges 15, which with contact compression spring 51 against the Surfaces 49 and 50 of the recess are pressed,

at least in the middle position of the electromagnetic switching device. The lateral sliding out of the Contact bridges are provided by lugs 15a (see FIG. 3) which engage in pockets 14c of the contact slide 14, prevented. In one end position of the switching device that contact bridge 15, which is on the fixed contacts 17 comes to rest, moves against the force of the contact compression spring 51 and the necessary contact force transferred to the contact points.

The mounting of the lifting armature 7 and the contact slide 14 in the reversing levers 10, 11 is shown in FIG and 8 shown enlarged in section, namely in the middle position of the reversing levers 10, 11, d. H. able to at which the air gaps 18 and 19 (see FIG. 1) are the same size. The representation of Fig.8 applies to both Deflection lever 10, 11 with depressions 106, 116 as well with grooves 41,42.

The material thickness 59 of the guide part 8 can be made relatively thin, as a result of which the mounting of the guide parts 8 in the recesses 10a, 11a of the deflection levers 10, 11 comes very close to ideal blade mounting. As is well known, the cutting edge mounting is ideal when the cutting edge engages razor-sharp in a recess, as the friction losses are then almost zero. The deburring of the guide part 8 carried out by conventional means, such as drums or galvanic pickling, results in a cutting edge shape 8a which engages in a recess with a recess radius 10 * or 1 \ x, which has to be slightly larger than the radius of the cutting edge 8a , whereby an almost frictionless rolling of 8a to 10 * or 11 χ is guaranteed.

The conicity 58 of the recess 10a, 11a in the deflection levers 10, 11 is so large that in an end position of the electromagnetic switching device there is still a small residual opening angle between the surfaces 8b of the guide part 8 and the surfaces 10, 11 running parallel to the bearing axis of the deflection levers 10, 11. iOab, ttaa, U ab runs.

The storage conditions according to FIG. 8 result in similar conditions as in FIG. 7, even if, for technical reasons of manufacturability, the thickness of the projection 14a, 14b of the contact slide 14 is made thicker. The support line of the circular surface 46 on circular surface 47 of the recess tob, lib or grooves 41, 42 in turn results in rolling and thus an almost wear-free mounting, provided that the angle 48 in the end position of the switching device between the surfaces of the projection 14a, 14b and the surfaces 106a, TOBB, iiba.Ubb the recess tob, 11 b or groove 41,42 is positive.

The effectiveness of the frictionless guidance and storage of the armature 7 in the magnet system and the contact slide 14 in the housing of the electromagnetic switching device can be influenced by a The coupling formed by the deflection lever 10, 11, armature 7 and contact slide 14 is as free from play as possible Parallelogram. In Fig. 6 shows a possibility for play-free storage. The contact slide is designed in two parts, the right half 52 is provided with a guide pin 53 which is in a blind hole 54 of the left half 55 slides. Between the two contact slide halves 52 and 55 is one Compression spring 56 arranged, which ensures that the cutting edge bearing points between reversing lever 10, 11, Lifting armature 7 and contact slide halves 52,55 are kept free of play. All you have to do is ensure that the Compression spring 56 produces higher forces in all operating positions than the sum of all contact pressure forces.

Dividing the contact slide in two has the advantage of freedom from play, but it is an additional one Expenditure, which, at least for small switchgear sizes, is controlled by lever with »controlled Stiffness «is avoidable. The section 57 of the reversing lever 10, 11 (see Fig. 1) is here like this designed and through the appropriate choice of material (a thermoplastic, which from an upper temperature limit has a pronounced cold flow kink, e.g. B. a polycarbonate) it is ensured that the parallelogram exists from parts 7,10,11,14, under tension is inserted into the switching device, d. H. an excess is due to the suspension of the sections 57 of the reversing lever balanced. Subsequent tempering balances the tension in sections 57 of the deflection lever 10.11 caused by cold flow.

For this purpose 3 sheets of drawings

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Claims (9)

Patent claims: 1. Electromagnetic switching device, consisting of a magnetic drive with a permanent magnet arrangement and a yoke surrounding a bobbin, the through core hole of which has a lifting armature contains, which actuates a contact slide via lever, which is parallel to the longitudinal axis of the The bobbin is slidably arranged and carries spring-loaded contact bridges, which are opposite each other at least two fixed contacts are assigned, the coil body two at a distance having adjacent chambers each receiving a coil winding and the permanent magnet arrangement is symmetrical to the longitudinal axis of the bobbin between the two chambers, polarized at right angles to the longitudinal axis of the bobbin and a through opening corresponding approximately to the diameter of the core hole of the coil former for the armature, which has a non-magnetic guide part and both of its end faces with those located in the area of the respective end openings of the core hole of the coil former Cooperate pole faces of the yoke, characterized in that the in the housing (16) and the housing cap (23) of the switching device mounted deflection lever (10, 11) on the dem The ends facing the magnetic drive carry the lifting armature (7) via the guide part (8) and spatially set, wear the contact slide (14) at the other ends of the reversing lever and also spatially set and the reversing lever (10, 11) together with the lifting armature (7) and the contact carrier (14) in the manner of a tightly coupled parallelogram works. 2. Electromagnetic switching device according to claim 1, characterized in that the guide part (8) of the lifting armature (7) and / or the ends of the contact slide (14) with their front ends in recesses (10a, IQb, 11a, holder deflection lever (10 , 11) are inserted and the front ends are enclosed by the recesses (10a, 10b, 11a, Wb) of the reversing levers (10,11) while maintaining the necessary bearing play. 3. Electromagnetic switching device according to claim 1 or 2, characterized in that at a rotationally symmetrical design of the guide part and the lifting armature, the recesses in the reversing levers are rotationally symmetrical, conical blind holes. 4. Electromagnetic switching device according to claim 1 or 2, characterized in that when the lifting armature (7) and / or contact slide (14) is not rotationally symmetrical, these are inserted into rectangular recesses (10a, 106, 11a, Wb) of the deflection lever (10,11) and that the surfaces (10aa, 10aZ), 106a, 10bb, 11a, Wab, 116a, Wbb) of the recess (10a, 106, 11a, Wb) running parallel to the bearing axis of the reversing levers (10, 11) are conically shaped. 5. Electromagnetic switching device according to claim 1 or 4, characterized in that the Lifting armature (7) and / or the contact slide (14) inserted into grooves (41, 42) in the reversing lever (10, 11) are and for the spatial fixation of lifting armature (7) and / or contact slide (14) in the direction of Longitudinal axis of these grooves (41, 42), the grooves (41, 42) are interrupted by webs (43, 44) which in Recesses (45, 46) of the front ends of the guide part (8) of the lifting armature (7) and / or of the Engage the contact slide (14). 6. Electromagnetic switching device according to claim 1, characterized in that the guide rod (33) of the lifting armature (32) and / or the ends of the contact slide (38) via joints the reversing levers (35) are connected, which are designed such that the front ends of the Guide rod (33) and / or the contact slide (38) with cylindrical bores transversely to the longitudinal axis are provided and which have fork heads (34) on the reversing levers (35) or directly via cylindrical hinge pins (37) on the reversing levers (35) are hinged. 7. Electromagnetic switching device according to one of claims 1 to 6, characterized in that the reversing levers (10, 11) are made of thermoplastics and are shaped so that they have a controlled cold flow behavior. 8. Electromagnetic switching device according to claim 7, characterized in that the through Deflection lever (10, 11), lifting armature (7) and contact slide formed parallelogram under pretension into the housing parts, housing (16) and housing cap containing the bearing points of the reversing lever (23) are used and that the property by tempering the fully assembled switching device the cold flow of the reversing lever (10, 11) is used for a play-free parallelogram function will. 9. Electromagnetic switching device according to one of claims 1 to 6, characterized in that the contact slide consists of two halves (52, 55) and that the two contact slide halves (52, 55) via a blind hole (54) in the contact slide half (55) and a guide pin (53) in the contact slide half (52) in the direction of the longitudinal axis of the contact slide halves (52, 55) are and that a play-free parallelogram function of the lever (10,11), lifting armature (7) and contact slide halves (52,55) formed by a parallelogram in the direction of the Longitudinal axis of the contact slide halves (52,55) acting compression spring (56) is achieved.