RU2411600C2 - Two-position electromagnet - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: two-position electromagnet consists of two fixed symmetrical parts of magnetic conductor 1 and 2, in which the following components are installed: one coil in each, 3 and 4, conductor 5 and 6, segments 7 and 8, and movable part of magnetic conductor, comprising cylindrical anchor 9 with circular ledge in medium part and non-magnetic stem 10. Conductors 5 and 6 are arranged in the form of polyhedron with hole coaxial to axis of stem 10. Permanent magnets 11 and 12 are arranged between faces of conductors 5 and 6 and segments 7 and 8. Non-magnet stem 10 is rigidly connected to anchor 9 and is installed with the possibility of free movement along its axis.

EFFECT: development of two-position electromagnet, providing for stable high force of anchor gravitation to fixed parts of magnetic conductor.

1 dwg

Description

The invention relates to two-position electromagnets, relates to bistable electromagnetic drives and can be used for drives of switching devices, in particular, in high voltage vacuum circuit breakers with a magnetic latch.

Known electromagnetic drive for a vacuum circuit breaker, consisting of a fixed part of the magnetic circuit, a moving part, two coils and permanent magnets (Vacuum Circuit Breakers Series BP0 and BP1. Operation manual NKAI. 674152.006 RE, Rivne, 2003). The moving part of the magnetic circuit - the anchor - is a parallelepiped made of soft magnetic material. Coils are located in space parallel to each other and have rectangular openings. An anchor is inside the hole of the coil. The fixed part of the magnetic circuit is a package of rectangular ferromagnetic plates. The plates have rectangular holes and two rectangular protrusions that are directed into the hole and are located opposite one another in the middle of the hole. Inside the opening of the plate package, there are coils and an anchor that moves freely in the opening of the coils. Permanent magnets are located on the surface of the protrusions. The thickness of the magnet is chosen so that it almost completely fills the gap between the end face of the protrusion of the fixed part of the magnetic circuit and the side surface of the armature. The moving part also includes a non-magnetic rod, which is rigidly fastened to the anchor. The rod transmits the movement of the armature to the movable contacts of the vacuum interrupter chambers of the switch. This drive is a two-position because it has two stable positions, which are provided by a magnetic latch.

The disadvantage of this design is the relatively small holding force of the movable part of the drive, which is created in one gap between the end of the armature and the fixed part of the magnetic circuit and is limited by the magnetic induction of saturation of the material of the magnetic circuit.

Known two-position electromagnet, consisting of a fixed part of the magnetic circuit, containing a coaxially located core, two coils, permanent magnets, and a moving part, including a non-magnetic rod and at least one armature (RF patent No. 2276421, H01F / 08, publ. 10.05. 2006). The core is cylindrical. The device also contains an annular body, the plane of the ends of which are parallel to each other and perpendicular to the axis of the fixed part, the inner diameter of the annular body exceeds the outer diameter of the annular protrusion on the core. Non-magnetic parts are located in the gap between the annular protrusion of the core and the housing, and these parts in azimuth only partially fill the gap, coils are located between the core and the housing on both sides of the annular protrusion on the core, permanent magnets are located outside the part of the gap occupied by the non-magnetic parts between the annular protrusion of the core and case. A non-magnetic rod is located in the core hole. The axial size of the rod part with a diameter that is equal to the diameter of the hole in the core exceeds the axial size of the fixed part of the magnetic circuit by the amount of travel of the movable part, and two disk-shaped anchors coaxial with the rod fixed to the ends of the rod part with a diameter equal to the diameter of the hole in the core.

The disadvantage of this design is that the force of attraction of the armature to the fixed parts strongly depends on the magnetic gaps between the magnet and the core, as well as between the magnet and the body, while minor magnetic gaps lead to a significant decrease in the force of attraction of the armature to the fixed parts of the magnetic circuit.

The objective of the invention is the creation of a two-position electromagnet, providing a stably high force of attraction of the armature to the fixed parts of the magnetic circuit.

This is achieved by the fact that in a two-position electromagnet, consisting of a fixed part of the magnetic circuit, containing a coaxially arranged core, two coils, permanent magnets, and a moving part, including a non-magnetic rod and at least one armature, the fixed part of the magnetic circuit is made of two symmetrical parts , in which one coil is located, the core is made in the form of a polyhedron, with a hole coaxial with the axis of the rod, segments are placed along the faces of the core, and permanent magnets are located between s core and segments, and the movable part of the magnetic circuit comprises a cylindrical anchor having an annular protrusion in the middle part, and a nonmagnetic rod is rigidly connected to the armature and mounted for free movement along its axis.

Figure 1 presents a two-position electromagnet, figure 2 is a top view thereof.

A two-position electromagnet is made of two symmetrical fixed parts of the magnetic circuit 1 and 2, in which one coil 3 and 4, a core 5 and 6, segments 7 and 8 are located, and a moving part of the magnetic circuit containing a cylindrical armature 9, with an annular protrusion in the middle part, and non-magnetic rod 10 (Fig. 1). The cores 5 and 6 are made in the form of a polyhedron with a hole coaxial with the axis of the rod 10 (Fig. 2). Permanent magnets 11 and 12 are located between the faces of the core 5 and 6 and segments 7 and 8 (figure 2). Segments 7 and 8 are placed along the faces of the core 5 and 6. Segments 7 and 8, cores 5 and 6 are made of soft magnetic material. The movable part of the magnetic circuit is located between two stationary symmetrical parts of the magnetic circuit 1 and 2. Non-magnetic rod 10 is rigidly connected to the armature 9 and is installed with the possibility of free movement along its axis.

The device operates as follows.

In the “off” position, the anchor 9 is pressed against the fixed part of the magnetic circuit 2, which contains the core 6, segments 8, permanent magnets 12 and coil 4. With deenergized coils 3 and 4, due to the magnetic flux created by the permanent magnets 12, the anchor 9 is reliably held in this position. The holding force created by this magnetic flux is greater than the attractive force created by the magnetic flux through the armature 9 and the opposite fixed part of the magnetic circuit 1 because there is a non-magnetic gap between the armature 9 and the fixed part of the magnetic circuit 1. If a current of a corresponding magnitude and direction is passed through a coil 3 located on the nonmagnetic gap side, and a current of the same magnitude but opposite direction is passed through a coil 4, then the magnetic flux generated by the current of the coil 4 will reduce the magnetic flux created by the permanent magnets 12 and the magnetic flux created by the current in the coil 3 will increase the magnetic flux created by the permanent magnets 11, and the armature 9 will begin to move. In this case, the non-magnetic gap between the armature 9 and the magnetic circuit 1 will begin to decrease, and the non-magnetic gap between the armature 9 and the magnetic circuit 2 will increase. Having reached the fixed part of the magnetic circuit 1, the armature 9 will stop and remain in this position after turning off the current in the coils 3 and 4, due to the magnetic flux created by the permanent magnets 11. The operation "on" is completed. When passing a current of the same magnitude and opposite direction through coils 3 and 4, the movable part of the two-position electromagnet will return to its original position.

A stably high force of attraction of the armature to the fixed parts of the magnetic circuit is achieved due to the fact that the force pressing the armature to the fixed part of the magnetic circuit is created in two gaps - between the annular protrusion of the armature and the magnetic circuit and between the armature and the core. Reducing the magnetic gaps between the permanent magnets and segments on the one hand and between the permanent magnets and the core on the other hand reduces magnetic losses, which, accordingly, leads to an increase in the force of attraction of the armature to the fixed parts of the magnetic circuit.

Claims (1)

A two-position electromagnet consisting of a fixed part of the magnetic circuit, containing a coaxially located core, two coils, permanent magnets, and a moving part, including a non-magnetic rod and at least one armature, characterized in that the fixed part of the magnetic circuit is made of two symmetrical parts, which are located along one coil, the core is made in the form of a polyhedron with a hole coaxial with the axis of the rod, segments are placed along the faces of the core, and permanent magnets are located between the faces with rdechnika and segments, and the movable part of the magnetic circuit comprises a cylindrical anchor having an annular protrusion in the middle part, and a nonmagnetic rod is rigidly connected to the armature and mounted for free movement along its axis.

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