WO2000011695A1 - Electromagnetic rotating armature relay - Google Patents

Abstract

The relay has a U-shaped yoke (2) with a coil (3) and two parallel pole shanks (21) between which a rotating armature (4) can pivot between an angular rest position and an angular working position. A contact spring (7) that cooperates with at least one fixed contact (81, 91) is actuated by the armature by means of a control cam. The movement of the armature is therefore limited in the direction of the working position and that of the rest position by spring resistance as opposed to a stop. As a result, the relay makes virtually no noise when switching occurs.

Description

description

Electromagnetic rotary armature relay

The invention relates to an electromagnetic rotary armature relay

- a base made of insulating material that defines a bottom side,

- a U-shaped yoke, which stands on the base with two parallel pole legs perpendicular to the base,

- A coil for generating a magnetic flux m the pole legs, the pole legs each having yoke pole surfaces m in the form of cylinder segments on their inner sides, - with an armature which is mounted rotatably between the coil and the base between the pole legs about an axis parallel to these, the armature its outer ends each have peripheral armature pole faces in the form of cylinder segments, which face the yoke pole faces in a contact-free manner at a predetermined working worm position, the armature being biased into a rest worm position by a return spring,

- furthermore with at least one mating contact carrier anchored in the base with a fixed contact and - at least one contact spring which can be actuated by the armature and which carries at least one movable contact which interacts with the fixed contact and is connected to a connection guided through the base.

Electromagnetic relays for switching direct current loads, such as are preferably used in motor vehicles, cause disturbing switching noises in the passenger compartment. In order to reduce this switching noise caused by the impact of a hinged armature on a pole face or by falling back on a stop or by the impact of switching contacts, it is known, for example, to use a double housing with sound-reducing properties. and at least partially fill it with sound-absorbing materials. These known measures are complex and expensive, they increase the volume of a relay and have only a sound-damping or sound-damping effect, while the actual problem of sound generation is not solved.

A relay of the type mentioned at the outset, as is known in principle from US Pat. No. 3,261,943, has a rotating armature magnet system which switches by means of a rotational movement, the pole faces of the armature sliding contactlessly between the yoke pole faces and thus at least not causing armature stop noises. However, the overall structure of the relay described there is still relatively complicated and voluminous. In addition to the U-shaped yoke, the magnet system there has a vertical core which is arranged parallel to the yoke legs and which carries the coil; this results in a relatively large overall height of the relay. The movable contact spring is connected to the armature as a bridge contact spring, one of two contact limbs simultaneously effecting the armature return position, as a result of which the armature stop in the rest position does not experience any damping and thus causes a switching noise. In addition, a changeover contact, as is desirable for various applications, cannot be implemented in the construction there.

The aim of the present invention is to create a relay of the type mentioned at the beginning, in which the noiseless switching movement of the rotary armature is used, but at the same time a simpler structure, a more versatile design option with opener, closer and changeover design, and also with Falling back of the anchor m the rest position of any impact noise is avoided.

According to the invention, this aim is achieved in a first embodiment of the invention in that the coil is on a perpendicular to the pole legs serving as a core section of the yoke is arranged that between the coil and the armature a non-magnetic bearing plate for the armature is arranged parallel to the bottom side, that the contact spring is arranged below the armature and by a switching cam connected to the armature is actuated and that the armature movement m is the rest angle position also limited by spring force.

In the case of the rotary armature system used in accordance with the invention, the switching movement takes place almost silently, namely in both directions of movement of the armature. The armature is mounted on the bearing plate by means of a bearing journal, so that there is space on the underside of the armature for the contact system. The bearing pin preferably has an extension on the underside of the armature, which forms or carries the switching cam in the form of an eccentric circumferential enlargement. This means that the switching cam can be formed in one piece with the bearing journal or can be connected to the bearing journal or to the armature itself by spitting or plugging on. The rotary movement of the armature is transmitted to the prestressed contact spring by means of this switching cam. The impact speed of the

Contacts, which is a measure of the contact noise, are reduced in such a way that a significant reduction in noise of the impinging switching contacts is also achieved. By designing the switching curve, the switching time and the contact speed of the contacts can be optimized and variably determined.

In a further advantageous embodiment, the contact spring is biased in the direction of the working angular position of the armature toward a make mating contact, while the separately provided return spring acts on the armature against the pretension of the contact spring. This way, through the combination of contact spring and return spring ensures that the armature movement is limited by spring force both in the pulling direction and in the falling direction and an impact noise is avoided in both directions. In the rest, angular position of the armature, the contact spring is pressed by the switching cam under the action of the return spring against its own bias against an NC counter contact, if one is provided.

In a second embodiment of the invention, the above object is achieved in a relay of the type mentioned above in that the coil is arranged on a central section of the yoke serving as the core and perpendicular to the pole legs, that between the coil and the armature a non-magnetic bearing plate for the Anchor is arranged parallel to the bottom side and that the contact spring is attached to the underside of the armature and carries the movable contact on a sliding contact leg preloaded in the radial direction, the movable contact having at least one of the two predetermined angular positions of the armature with a fixed contact opposite in the radial direction cooperates.

In this second embodiment of the relay according to the invention, the rotational movement of the rotary armature magnet system is also used to produce an almost silent switching movement. To reduce the switching noise in this case, however, the contact spring is not fastened separately from the armature, but is directly connected to the armature, while the movable contact is connected as a sliding contact in a grinding movement with an opposing normally open and / or normally closed contact. Power can be supplied to this contact spring connected to the armature either via a further sliding contact radially opposite the movable contact or via a flexible lead in the form of a strand. The rotary armature magnet system used according to the invention in both embodiments has the advantage that the work of the magnet system, that is to say the product of force and displacement, is almost the same as that of a conventional hinged armature relay with a comparable size; This means that, with the same size, the same characteristic values can be achieved for the low-noise relay as for a conventional milk-type armature relay with loud switching noise.

The relay according to the invention achieves a particularly effective response behavior when the armature has hm angled pole pieces at its two outer ends, which form the cylindrical armature pole faces; in this case the anchor has a U-shape. The bearing plate is also preferably made of a non-ferromagnetic metal, and it can serve both for fastening and as a power supply for the contact spring. Furthermore, there is a particularly simple and effective structure of the relay if at least one of the pole legs has a connecting pin guided through the base as a current supply to the contact spring. If the contact spring is attached to the metallic bearing plate, the current can be supplied directly to the contact spring via one or both pole legs and via the bearing plate without additional parts. If higher currents are to be switched, it is expedient to connect the movable contact directly to the bearing plate or to one of the pole legs via a wire.

As mentioned, the one-piece yoke carries the coil as the core on its central section. In order to be able to arrange the bobbin on this central section, it can either be produced as an injection molded part on the curved yoke or it can be provided with an elongated slot and can thus be attached subsequently.

In order to optimize the force / displacement curve of the characteristic of the magnet system for the force / displacement characteristic of the field replacement, you can the two pole legs of the armature can be made variable in the area of the pole faces; This means that the armature pole surfaces have, for example, obliquely guided or arcuately curved boundary edges relative to the yoke pole surfaces.

The invention is explained in more detail below using exemplary embodiments with reference to the drawing. 1 and 2 show a relay designed according to the invention in a perspective view from two sides, FIG. 3 shows the relay from FIG. 1 in an exploded view,

FIG. 4 shows the relay from FIG. 1 in a longitudinal section through the armature axis,

5 shows the yoke and the armature of the relay from FIG. 1 - slightly modified - in a perspective detailed view, FIGS. 6 and 7 a sectional view VI-VI from FIG. 4 of the armature in the rest angular position and in the working angular position,

8 shows a view corresponding to FIG. 6 of a relay with a modified contact spring in the rest position (dashed line) and in the working position (solid line) of the armature and

9 shows a sectional view, comparable to FIG. 8, of a relay with a further modified contact spring shape, likewise in the rest angular position (dashed line) and in the working angular position (solid lines) of the armature.

The relay shown in Figures 1 to 5 has a base 1, on which a magnet system with a U-shaped yoke 2 is attached. The yoke 2 consists of two parallel pole legs 21 and a central core section 22. On the latter, a coil 3 with a coil body 31 and a winding 32 is arranged. In addition, the magnet system has an armature 4, which is rotatably mounted by means of a bearing pin 5 in a bearing plate 6 connected below the coil with the pole legs 21.

The coil former 31, which is made of thermoplastic plastic, can be coated directly around the core section 22 be generated. However, it can also be provided with an elongated slot 33 (FIGS. 1 and 3) and thus plugged onto the core section 22 before it is provided with the winding 32. On the flanges of the coil body, projections 34 are formed, in which injected coil connection pins 35 are guided in an isolated manner to the base, where they are then led through the base 1 to the underside thereof, which serves as the bottom side 11, and to the outside.

The two pole legs 21 of the yoke are shaped at their ends to form connecting pins 23, which are led through the opening in the base 1 and serve as connections for a contact spring 7 or a movable contact 71 connected to it. After the winding 32 has been applied to the coil former 31 and the winding ends have been connected to the connection pins 35, the bearing plate 6 is fastened between the two pole legs 21 below the coil. The bearing plate consists of electrically conductive but not ferromagnetic metal. It serves for the central reception of the bearing pin 5 for the armature 4 and for the suspension of a return spring 51 for the rotating armature. In addition, the contact spring 7 is fastened to the bearing plate 6 with a fastening leg 72 (FIGS. 2 and 3). In the event that large currents are to be switched and the material or the cross section of the contact spring is not sufficient for this, an additional strand 73 is provided in the present example, which leads the current directly from the bearing plate 6 to the movable contact 71 at the free end of the contact spring 7 leads.

In the base 1, which is made of thermoplastic plastic, two injected (round or also) angular, electrically highly conductive wires (for example made of copper) serve as connecting pins and mating contact elements 8 and 9, each of which has welded or soldered fixed contacts, namely an opener contact 81 and carry a normally open contact 91. To protect the relay, a cap 10 is also placed, which with the base 1 is a closed housing forms. The housing gap is sealed by a potting 12.

The armature 4 has angled armature pole pieces 41 at its two ends downward, that is to say in the direction of the base, as a result of which it obtains an overall U-shaped shape. The contact system is accommodated in this space formed by the U-shaped armature 4 and the base 1, which results in a very compact design. As can best be seen in FIGS. 5, 6 and 7, the pole limbs 21 are curved inwards in the form of cylinder segments and thus form yoke pole surfaces 24 which are rotationally symmetrical to the armature axis and to which the armature with correspondingly curved outer pole faces 42 on the pole pieces 41 faces at a close distance.

In order to optimize the force / displacement curve of the characteristic of the magnet system for the force / displacement characteristic of the spring set, the two pole pieces 41 of the armature, which in the embodiment according to FIG. 3 run with their side edges 43 parallel to the side edges of the pole legs, can also 5 have obliquely cut, arcuately curved or modified in other ways side edges 44. These are then no longer parallel to the side edges 25 of the pole legs, so that the torque characteristic of the magnet system is changed in this way.

To actuate the contact spring, the bearing pin 5 has an integrally formed eccentric switching cam 52 in the area below the armature, which bears laterally on the contact spring 7 which extends transversely to the armature. The switching cam 52 is designed so that it presses the contact spring 7 with its movable contact 71 against the opener-fixed contact 81 in the rest position of the armature. The necessary burn-off safety is achieved by bending the contact springs 7. After the relay has been assembled, the function results as can be seen from FIGS. 6 and 7. In the rest, angular position of the armature (FIG. 6), the armature pole faces 42 are outside the area of the yoke pole faces 24. This position is achieved by the return spring 51. In this case, the switching cam 52 presses the contact spring biased into the working position to the normally open fixed contact 91 and presses it against the open fixed contact 81 against its bias.

When the magnetic circuit is excited, the armature 4 with its two pole pieces 41 experiences a torque which is greater than the opposite torque of the return spring 51; it rotates in the direction of the two pole legs 21. The cam curve of the switching cam 52 releases the prestressed contact spring 7, so that the movable contact 71 is closed with the normally open fixed contact 91. The further the armature 4 with its two pole faces 42 covers the yoke pole faces 24 of the pole legs 21, the smaller the torque of the armature 4; this means that the armature remains in its end position without a stop and therefore noiseless, in which the counter-torque of the return spring 51 and the torque of the magnet system are the same (FIG. 7).

When the excitation circuit is switched off, the armature 4 is turned back to its rest position according to FIG. 6 by the torque of the return spring 51 m, the switching cam 52 connected to the armature pressing the contact spring 7 with the movable contact 71 against the opener fixed contact 81. Here, too, there is no noise-causing jerk stop of the rotary anchor, since the rest position is determined by the counter-moment of the contact spring preload and the additional bending for fire safety.

In this relay, the impact speed of the contacts, that is to say the movable contact 71, on the fixed contacts 81 and 91, which is a measure of the contact noise, is determined by the switching curve of the switching cam reduced, so that the noise is already significantly reduced compared to conventional relays. By designing this switching curve, the switching time and the contact speed of the contacts can be optimized and variably determined depending on the requirements.

Another possibility of reducing the contact noise is shown in FIGS. 8 and 9, in which the contacts are each designed as sliding contacts.

FIG. 8, which shows a view of the armature corresponding to FIGS. 6 and 7, shows an embodiment in which the contact spring 7 is firmly connected to the armature 4. At its free end it has a vertically bent sliding contact leg 74, which is biased outward in the radial direction and carries a movable sliding contact 75. The opener fixed contact 81 and the normally open contact 91 are in this case next to each other on a circular path offset and arranged obliquely so that they the movable sliding contact in each case at the rest-winding position of the armature 4 (shown in dashed lines) or in the working-winding position (drawn with a solid line) face each other radially. The spring-loaded contact opens due to the inclined fixed contacts and generates the required contact pressure and burn-off safety. In the balance of forces (both in the working position and in the rest position) the anchor stops without a stop. In this case too, the contact spring 7 is electrically connected to the bearing plate 6 or to one of the pole legs 21 via a strand 73. Since the relay is otherwise constructed exactly as in the previous example, the function also results from the above description.

A further modification is shown in FIG. 9. As in the embodiment according to FIG. 8, the contact spring 7 has a movable sliding contact 75 which interacts with the fixed contacts 81 and 91 in the same way as before. Instead of the contact spring being connected via a strand 73 this according to FIG. 9 via a further sliding contact 76, which resiliently abuts a feed contact track 77 and remains in contact with the armature in both end positions thereof. It has two contact sections inclined relative to one another, on which the sliding contact 76 at the end of each

Switching movement runs up. The same braking effect is achieved as with the inclined counter-contacts 81 and 91 (as in FIG. 8) and together with these. The anchor end position is given by the balance of the increasing contact forces in the rest and working position. This lead contact track 77 can be anchored in the base 1 or connected to the bearing plate 6. Furthermore, it also applies to FIG. 9 that the function of the relay is the same as in the previous examples.

Claims

claims 1. Electromagnetic rotary armature relay with - a base (1) made of insulating material, which defines a bottom side (11), - A U-shaped yoke (2) which is perpendicular to the bottom side (11) on the base (1) with two parallel pole legs (21), a coil (3) for generating a magnetic flux in the pole legs (21), the pole legs (21) each having yoke pole faces (24) in the form of cylinder segments on their inner sides, - With an armature (4) mounted between the coil (3) and the base (1) centrally between the pole legs (21) about a parallel to this axis rotatable armature, which has peripheral armature pole faces (42) at its outer ends. in the form of cylinder segments which face the yoke pole faces (24) without contact at a predetermined working angular position, the armature being prestressed into a rest angular position by spring force, - further with at least one mating contact carrier (8,9) anchored in the base (1) with a fixed contact (81,91) and - with at least one contact spring (7) which can be actuated by the armature (4) and which has at least one with the respective fixed contact (81,91) cooperating movable contact (71) and is connected to a connecting pin (23) guided through the base (1), characterized in that the coil (3) on a perpendicular to the pole legs (21) as a core ( 22) serving central section of the yoke (2) is arranged in that a non-magnetic bearing plate (6) for the armature (4) is arranged parallel to the bottom side (11) between the coil (3) and the armature (4), that the contact spring (7) is arranged below the armature (4) and is actuated by a switching cam (52) connected to the armature (4), and that the armature movement into the rest angular position is limited by spring force. 2. Relay according to claim 1, characterized in that the armature (4) by means of a bearing pin (5) in the bearing plate (6) is mounted on the underside of the armature (4) to form the switching cam (52) in his Extent eccentrically enlarged. 3. Relay according to claim 1 or 2, characterized in that the contact spring (7) in the direction of the working angular position of the armature (4) is biased to a normally open contact (91) and that the return spring (51) against the bias of the contact spring (7) acts on the anchor (4). 4. Relay according to claim 3, d a d u r c h g e k e n n z e i c h n e t that the contact spring (7) in the rest angular position of the armature (4) by the switching cam (52) is pressed against its bias against an NC contact (81). 5. Electromagnetic rotary armature relay with - a base (1) made of insulating material, which defines a base side, - a U-shaped yoke (2), which is perpendicular to the base side on the base (1) with two parallel pole legs (21), - A coil (3) for generating a magnetic flux in the pole legs (21), the pole legs (21) on the inside of each Have yoke pole faces (24) in the form of cylinder segments, - With an between the coil (3) and the base (1) centrally between the pole legs (21) about a parallel to this parallel axis rotatably mounted armature (4), the peripheral armature pole faces (42) m shape at its outer ends has cylinder segments which face the yoke pole faces (24) without a stop at a predetermined working angular position, the armature being prestressed by a spring force m into an idle angular position, - Furthermore with at least one mating contact carrier (8,9) anchored in the base (1) with a fixed contact (81,91) and - With at least one contact spring (7) which can be actuated by the armature (4) and carries at least one movable contact (71) which interacts with the respective fixed contact (81, 91) and is connected to a connecting pin (23) guided through the base (1) , characterized in that the contact spring (7) is fastened to the underside of the armature (4) and carries the movable contact (75) on a sliding contact leg (74) which is biased outward in the radial direction, the movable contact (75) being at least one the predetermined angular positions of the armature (4) cooperates with a fixed contact (81, 91) opposing the radial direction. 6. Relay according to claim 5, characterized in that the contact spring (7) has a movable sliding contact (75) radially opposite another sliding contact (76) which in both switching positions of the armature (4) with a lead contact track (77) Is touch. 7. Relay according to claim 5, characterized in that the contact spring (4) is connected via a flexible feed line (73) to an associated connection element (6, 23). 8. Relay according to one of claims 1 to 7, so that the armature (4) at both outer ends towards the base (1) has angled pole pieces (41) which form the cylindrical armature pole faces (42). 9. Relay according to one of claims 1 to 8, d a d u r c h g e k e n n z e i c h n e t that the bearing plate (6) consists of non-ferromagnetic metal and serves to fasten the and as a power supply for the contact spring (7). 10. Relay according to one of claims 1 to 9, d a d u r c h g e k e n n z e i c h n e t that at least one of the pole legs (21) has a through the base (1) lead pin (23) as a power supply to the contact spring (7). 11. Relay according to claim 9 or 10, so that the movable contact (71) is connected via a wire (73) to the bearing plate (6) or to one of the pole legs (21). 12. Relay according to one of claims 1 to 11, so that the coil former (31) is arranged as an injection molded part on the central section (22) of the yoke (2). 13. Relay according to one of claims 1 to 11, characterized in that the coil former (31) has a radial slot (33) corresponding to the thickness of the core section (22) of the yoke over its entire axial length. 14. Relay according to one of claims 1 to 13, that the armature (4) is biased into its rest angular position by means of a screw return spring (51). 15. Relay according to one of claims 1 to 14, so that at least one of the yoke pole faces (42) and the respectively associated armature pole face (24) have boundary edges (44; 25) which are not parallel to one another at least on one side.