DE1902610B1 - Electromagnetic relay - Google Patents

Description

The invention relates to an electromagnetic Relay.

Electromagnetic relays have the disadvantage that, due to the temperature dependence of the coil resistance, require a higher excitation voltage, the larger the permissible ambient temperature range is in which they are supposed to function, and that they also have all the more excitatory power need, the greater the contact force and the number of contacts to be actuated. the Avoidance of this disadvantage and the creation of a relay, its ambient temperature and the The number of contacts to be actuated or their set contact force have no significant influence have on the excitation power, according to the invention by the combination of the following features achieves that:

a) at least one such permanent magnet is provided, in which the influence of the temperature coefficient on the force of the armature is greater than on the permanent magnetic field,

b) a significant proportion of the permanent magnetic attraction force acting on the armature the contact spring (s) is saved,

c) the permanent magnetic attraction force stored by the contact spring tongues the contact force certainly.

The interaction of the aforementioned features, some of which are known, leads in the present case Fall to a mutual support in the direction that the set contact force in a relatively large ambient temperature range and also with different excitation power remains constant.

Further details of the invention are shown in FIGS. 1 to 11 can be found.

F i g. 1 shows the schematic structure of a permanent magnet system with magnetic flux profiles Φι , Φ [ in the middle position of the armature 1;

F i g. 2 shows the schematic structure of the system according to FIG. 1, but with a one-sided rest position of the armature and the resulting flows Φ ₂ , Φ ₂ '. Since the flux curve Φ _{1 is} negligibly small compared to the flux curve Φ ₂ , it follows that permanent magnet systems with two corresponding air gaps have a significantly better efficiency than systems with only one air gap. A high efficiency of the permanent magnet system is gaining in importance when it generates beneficial forces or power reserves, e.g. B. to compensate for the effects of heat, are stored;

F i g. 3 is a section CC of a symmetrically constructed polarized relay of FIG. 4;

Fig. 4 is a section AA ' of Fig. 3;

Fig. 5 is a section BB ' of Fig. 4;

F i g. 6 to 10 show the interplay of forces in the cold k> and warm magnet system with various compensation springs in the armature's range of motion;

Fig. 11 shows a special center bracket of the Anchor.

The magnet system shown is symmetrical with regard to its X and Z center lines, so that not all mirror-inverted parts or forces are shown and labeled.

In the figures:

3.3 '

4.4 '

5.5 '

8, 8 ', 8 "

9.9 '

10

11.11 '

12.12 '

13.13 '

14.14 '

15.15 '

16

17th

18th

19th

20, 20 ', 20 "

21, 21 ', 21 "

22.22 '

23.23 '

24.24 '

25, 25 '

26th

d /1

h / 3, Λ ■

H ■■

h =

M ₁ , M ₂ , M ₃ , M ₄ , M ₅ =

M ₁ ', M ₂ ', M ₃ ', Mi, M' _s =

O =

P31 Ρίι -

P, =

Armature armature bearing bearing plates pole pieces permanent magnets bobbin coil

Adjusting flaps Adjusting flaps Bridge Adjusting springs Adjusting springs Shoulders, actuators, pimple adjustment block, stop Coil connection, base plate, contact connections, contacts, contact springs, contact spring tongues Center contacts coil connection pins connection point half contact path clearance between stop and adjusting spring 12, 12 ', partition thickness, spring characteristic of the contact spring tongues 23, 23 'spring characteristics of the adjusting springs 11,11' spring characteristics of the Adjusting springs 12,12 'transverse direction in which the Armature 1 moved pivotably and in which the pimples 15, 15 'are adjustable. Length of the contact spring 22, 22 'from the connection to the contact 21, 21' Length of the contact spring 22, 22 'from the connection to Connection curves that represent the force-displacement curve of the armature 1 in the cold state Curves showing the force-displacement curve of the anchor 1 in the warm State represent middle position

Adjusting forces of the armature 1 with respect to the pole pieces 4, 4 'in the cold state Adjusting forces of the armature 1 with respect to the pole pieces 4,4 'in the warm state End force with which the contact spring tongues 23, 23 'against the pimples 15, 15' and thus against the tightening direction of the armature 1 act. Neglecting friction and the low level of friction

Because of the connecting parts 26, P ₂ = contact force P ₄ = end force with which the adjusting springs 11, 11 'counter to the tightening direction of the armature 1
works

P ₅ , P ₈ = restoring forces with which
the armature 1 lifts off the pole pieces 4, 4 'in the cold state after excitation

Pi, P ₈ '= restoring forces with which

the armature 1 lifts off the pole pieces 4, 4 'in the warm state after excitation

P ₆ , P ₉ = force with which the armature 1, in the cold state in the central position, is fixed by the bias of the adjusting springs 12, 12 '

Pt, Ρ, = forces with which the armature 1, in the warm state in the central position, by the bias of the adjusting springs 12, 12 ',
is fixed

f * 7> Λο = final power with which the adjusting springs 12, 12 'act against the tightening direction of the armature 1

S = half anchor travel
V = longitudinal direction in which the

Pimple 15.15 'are adjustable X, Z = center lines
Φ ,, Φ {, Φ _ζ , Φ { = TeiJ continuous flows

The armature 1 is mounted within the coil 7 in the diamagnetic bearing plates 3, 3 'and pivotably about the armature bearing 2 between the ferromagnetic pole pieces 4, 4'. This measure increases the efficiency because there is no electromagnetic leakage flux in the center of the coil and the electromagnetic flux generated is 100% effective. The bearing plates 3, 3 'are held in the shoulders 13, 13' and spot-welded to the pole pieces 4, 4 '. At the ends of the armature 1, the actuating pieces 14, 14 'and on them the adjusting springs 11, 1Γ, which rest on the flanks of the armature and at the same time serve as magnetic separating plates, are riveted or spot-welded. The permanent magnets 5, 5 'are located between the pole shoes 4, 4'. In order to obtain a compensation over as large a temperature range as possible, which corresponds as precisely as possible to the temperature coefficient of the coil, the permanent magnet 5 or 5 'can for example be composed of several magnets with different thermal coefficients, in parallel or in series. On the actuating pieces 14, 14 ', pimples 15, 15' are formed by means of insulating heat shrink tubing. The flanges of the bobbin 6 carry coil connections 18 which make contact with the coil connection pins 25, 25 'as soon as the magnet system is connected to the base plate 19 in a manner known per se. The base plate 19 is equipped with the contact connections 20, IV, 20 "and the coil connection pins 25, 25 '. The contacts 21, 21', 21" are brazed or spot-welded to the contact connections 20, 20 ', 20 ". 22 'are folded and also hard-soldered or spot-welded to a terminal pin in a known manner. The center contacts 24, 1A' are spot-welded at the junction 26 with the contact spring 22 and run in a fork-like manner along the likewise fork-shaped contact spring tongues 23, 23 ', so that at Actuation of the contact path 2a (FIG. 6) is greater approximately in accordance with the ratio γ from the path of the connection point 26. Between the contact spring tongues 23, 23 'there is a pimple 15 or 15' which, when the armature moves, the contact spring in ίο // - direction actuated.

The curve M ₁ (FIG. 6) shows the force-displacement curve of the armature 1 according to FIG. 1 and 2 with cold and curve M [ with warm permanent magnets 5, 5 'and corresponding thermal coefficients. As a result, the actuating force P ₁ 'is smaller than P ₁ . The point O in FIG. 6 corresponds to the anchor position in the central position according to FIGS. 1, 3 and 5, and thus s = half the anchor path. During the movement of the armature 1 from its center position O in a // direction, the pimple 15 takes the contact spring tongue 23 or 73 with it with almost no resistance until the center contact 24 or 24 'touches the contact 21 or 21'. The diagram according to FIG. 6 shows the contact distance 2a and also that the overcoming of this contact distance takes place with insignificant expenditure of force. In the further course of the armature movement, the force-displacement curve M ₁ , M {increases progressively up to the actuating force Pi, P ₁ 'according to the form!

at. μ F d

Where:

Φ = the permanent magnetic flux acting in the air gap
s = the anchor travel measured by the message
/ ι = permeability
F = pole face
d - partition thickness or remaining air gap

In order to bring the armature 1 with its actuating force P ₁ into the opposite position, the Errcgerfiuß Φ _Ε must be greater than * $ ■ . However, if the operator

force P _1, the contact force P ₂ with the spring characteristic /, stored, then the excitation flux can be smaller by the proportion that is used to generate the contact force, without weakening the permanent magnetic flux. For P ₂ smaller than P _{1, the} following applies:
The higher the contact force or the number of contacts to be actuated, the lower the excitation power.

In this context, the above-mentioned measures to increase the permanent magnetic gain and electromagnetic efficiencies because both when excited Factors as a product correspond with each other and because of the resulting tightening force

Py =

Φ _Ε -φ)

d- µ-F

Naturally, the more useful it is, the more it is available.

As the ambient temperature rises and the excitation voltage remains constant, the exciter nut Φ _Ε weakens, as is well known, by 0.39% P ^ro degrees Celsius , corresponding to the change in resistance of the coil. To the-

Correspondingly, the permanent magnetic flux Φ would also have to weaken by a factor of 039% per degree Celsius temperature increase if the response voltage is to be almost constant. However, this is not desirable because permanent magnets with a temperature coefficient of more than 0.25% P ^ro degrees Celsius can only be used within a small temperature range and too high a loss of permanent magnetic flux interferes with the functionality of the magnet system. However, if, as in the present case, _{a substantial portion of the actuating force P 1 is} stored by the contact spring tongues 23, 23 'with the spring characteristic / 1 for the contact force P ₂ , then the actuating force is reduced according to the curve M _{2 in} FIG. 7 to P ₃ = P, - P ₂ or, when the temperature rises, the curve M ₂ to P ₃ = P ₁ '- Ρ ,, whereby the percentage of the reduced force is significantly higher than the permanent magnetic flux, which is reduced by the increased temperature. _{In addition, the contact force P 2} , and thus also the actuating force P ₃ or P ₃ ', can be largely changed within the area P ₁ ' smaller than P ₂ by adjusting the pimple 15 in the ^ direction, so that either a magnet with relative A small temperature coefficient can be used or at higher temperatures even less species-related excitation can be achieved than at lower temperatures.

Bending the adjusting tab 8 or 8 'against the _{adjusting springs 11, II' produces a force P 4} with the spring characteristic / 2 · Damil reduces the force-displacement curve Af ₃ = M ₁ - f ₂ on the relevant half of the movement of the armature 1 Correspondingly, at an increased temperature M ₃ = Ai ₂ ' ~ fz- On this one actuation _{half, the force-displacement curve M 3} or M ₃ moves into the negative force direction range, so that the armature moves with the force P _} = P ₃ - P ₄ or Pj = P ₃ - P ₄ lifts off the relevant pole piece. The balance of forces remains in the rest position of the anchor, corresponding to the rest position of the anchor on both sides according to FIG. 7. unchanged. This is of particular importance because, as is well known, pole relays with a one-sided rest position of the armature can replace unpolted relays in almost all applications and therefore the advantages of this invention are also accessible to applications that were previously reserved for unpolarized relays.

In the application example according to FIG. II, adjusting springs 12, 12 'are riveted or spot-welded to the adjusting tabs 9, 9' of the bridge 10 and provided with the pretension P _n due to the support on the adjustment bracket 16. The size of the preload can be adjusted by bending the adjusting tabs 9, 9 '. This creates a stable joint of the anchor. The distance h in FIG. 9 corresponds to the required play between an adjusting spring 12 or 12 'and the stop 17. which is permanently connected to the armature or is part of it. In a further embodiment of the invention, it is possible to shift the stable central position of the armature created in this way by adjusting the setting block 16 in one direction or the other.

Fig. 9 shows the force diagram for an average rest position. It is: Ai ₄ = M ₂ - / ₃ or M ₄ = M ₂ - / ₃ .

Since no noteworthy permanent magnetic forces act in the area of the central position of the armature, the armature is fixed with the force P 1 or P 1, for example. The restoring force on both sides is: P _K = P ₃ - P- in the cold and P _x '= P ₃ - P- in the warm state.

F i g. 10 shows the force diagram with three stable rest positions of the armature, the adjusting springs 12, 12 'having a flatter spring characteristic / ₄ than / ₃ for the middle rest position and holding the armature 1 in the center position via the stop 17 with the force P _9. The force- displacement curve M ₅ = M ₁ - / ₄ or M ₅ '= M ₂ - / ₄ changes the direction of force in the course of the armature movement so that the armature with the actuating force P ₁ , = P ₃ - Ρίο in the cold and with Pi ₁ = P ₃ - P ₁₀ in the warm state on the pole pieces 4 or 4 '. In this case, too, a lower actuating force P ' _{n has} to be overcome by the excitation power _{in the warm state than in the cold state P 11} . All these functions could not be satisfactorily fulfilled without storing a substantial part of the attraction force for the contact force P _2. In particular, the stable central position of the anchor, according to the diagram in FIG. 9, and the three stable rest positions of the armature, according to the diagram of FIG. 10, without storing a substantial part of the permanent magnetic attraction force for the contact force P ₂ therefore not be realized because with the known use of only one compensation spring only a certain force over a certain way can be stored, so that the disadvantageous complex relationships of an electromagnetic relay mentioned at the beginning cannot be eliminated.

The invention not only eliminates such disadvantages, but also creates a relay with stable one-sided, two-sided, middle and even three stable rest positions of the anchor with and without compensation of temperature influences.

Claims (11)

Patent claims: 1. Electromagnetic relay characterized by the combination of the following Features that a) at least one such permanent magnet is provided, in which the influence of the temperature coefficient on the force of the armature is greater than on the permanent magnet field. b) a substantial part of the permanent magnetic attraction force acting on the armature is saved by the contact field (s), c) the one stored by the contact spring (s) ^) permanent magnetic attraction force determines the contact force. 2. Electromagnetic relay according to claim 1, characterized in that the permanent magnet is formed from at least two permanent magnets, one of which has a temperature coefficient of less than 0.05 and another has one of more than 0.2. 3. Electromagnetic relay according to claim 1 and 2, characterized in that the armature has only one rest position by means of an adjusting spring (11). 4. Electromagnetic relay according to claim 1 to 3, characterized in that a provided for contact actuation pimple (15) between the two spring tongues (23,23 ') of a fork-shaped contact spring and adjustable in the longitudinal (V) or and transverse direction (H) is. 5. Electromagnetic relay according to claim 1 to 4, characterized in that the fork-shaped central contacts connected to the contact spring (24, 24 ') run along the contact spring tongues (23, 23') and their contact path is greater than the path at the junction (26). 6. Electromagnetic relay according to claim 1, 2, 4 and 5, characterized in that adjusting tabs (9, 9 ') are provided on which there are adjusting springs (12,12') which protrude over a stop (17), with Pre-tension on an adjusting block (16) and thus keep the anchor in a stable central position. 7. Electromagnetic relay according to claim 6 «characterized in that the setting block (16) is adjustable by bending. 8. Electromagnetic relay according to claim 6 and 7, characterized in that only between an adjusting spring (12 or 12 ') and the Stop (17) a contact takes place. . 9. Electromagnetic relay according to claim 1, 2 and 4 to 8, characterized in that the Anchor has a middle and two unilateral rest positions. 10. Electromagnetic relay according to claim 1 to 9, characterized in that the magnet system is firmly connected to the bearing plates (3, 3 '). 11. Electromagnetic relay according to claim i to 10, characterized in that the armature is mounted centrally within the coil and with its two ends between two permanent magnetic pole faces. 1 sheet of drawings '(P ¹