RU2683575C1 - Polarized two-stable long-way electromagnet with a double secondary magnetic chain - Google Patents

Abstract

FIELD: switching device.SUBSTANCE: invention relates to a polarized switching device and can be used in the design of relays or contactors with increased strokes for higher voltages or, for example, to create various releases for circuit breakers subjected to shock and vibration external influences. In a polarized double-stable long-stroke electromagnet with a double serial magnetic circuit, the articulated armature has two permanent magnets with pole tips, magnetized in different directions, equidistant and parallel to the axis of rotation. Axis of rotation is parallel to the winding located on the middle part of the H-shaped magnetic circuit, so that the armature is pulled only to one of the two sides of the H-shaped magnetic circuit and simultaneously has one of two possible stable positions.EFFECT: technical result is to increase the working stroke of the armature and the torque throughout the course, reducing the cross section of the magnetic circuit, increasing the stability of the ampere-turns of operation, improving the efficiency of the magnet and control circuit, increasing the resistance to external mechanical stress, reducing the size and weight of the device, facilitating the assembly process and adjusting the armature.1 cl, 6 dwg, 1 tbl

Description

The invention relates to the field of low-voltage electrical devices, in particular to polarized switching devices, and can be used in the design of relays or contactors with increased strokes for increased voltages, or, for example, to create various releases for circuit breakers subjected to shock and vibration external influences.

A huge number of structural circuits of magnetic circuits of polarized magnetic systems are known, described in various literature, [for example, 1-5, etc.], and which are analogues. Traditionally, authors in all information sources, depending on the desired result, prefer parallel (differential) or bridge circuits of magnetic circuits. However, all parallel and bridge circuits of magnetic circuits have a common drawback - the impossibility or limitation of increasing the working stroke of the armature in the given dimensions, because ampere-turns of operation always depend on the size of the working gap. Almost all the maximum values of the working clearances of the magnetic systems of various relays or contactors are within 1 ÷ 1.5 mm for bridge circuits, and 2 ÷ 2.3 mm for parallel (differential) ones. This circumstance severely limits the scope of polarized magnetic systems. So, for example, the well-known polarized relays of both domestic and foreign production have limitations on the switched voltages and power, the main or even the main reason for this is the impossibility of increasing the working gaps in the acceptable dimensions of the product. The main field of application of such relays is in networks with a voltage of 27 ÷ 36 V DC and 115 V AC at a frequency of 400 Hz. With the increased voltages (for example, more than 48 V) of direct current stated in the technical documentation, the real switched currents or the number of switching cycles of the product can be reduced to unacceptable values.

The serial magnetic circuit is described in sources [1-5 and others] only with a “passive” anchor and return spring (Fig. 1). It is believed that "... To return the anchor to its original position in a polarized electromagnet with a sequential-type magnetic system, as well as in neutral electromagnets, it is necessary to have a return spring" [1, 2, 3]. However, there are many known designs of polarized relays with a sequential type magnetic system, with an “active armature” (the magnet is in the armature) when a return spring is not required (Fig. 2). For the convenience of analysis and comparison, it is customary to divide magnetic systems of polarized electromagnets into two types - with “active” and “passive” anchors [7]. “Passive” anchors are soft magnetic steel anchors that do not contain a permanent magnet or winding, i.e. not having their own field. By “active” anchors we mean such anchors that contain a permanent magnet or control winding, i.e. having your own field. In such a system (Fig. 2a), when the operating voltage is applied to the winding, the active armature is repelled from the poles of the magnetic circuit due to counterpropagating polarizing Ф _п and control Ф _{at the} flows, and returns to its initial state (Fig. 2b) after removing the voltage from the winding, expense of the efforts created by own field. In this system, the anchor has one stable position.

In FIG. 3a and 3b, a bi-stable version of a magnetic system with an “active” armature and a magnetic focus is presented. After applying a control voltage to the winding (Fig. 3a), a magnetomotive force appears, which creates a control work flow Ф _у opposite to the polarizing Ф _п . An anchor, after comparing the control flow and the polarizing flow, begins to move (to repulse from the poles). To reduce consumption after operation and holding the armature in the actuated state (ensuring a second stable position of the armature), a magnetically conductive plate (stop) is added to the magnetic system, onto which the armature sticks after actuation. To ensure return (Fig. 3b), a reverse polarity voltage is applied to the winding to create a control flow for attraction directed in accordance with the polarizing flow. The anchor, breaking away from the stop, returns to its original state due to the efforts developed according to the polarizing magnet flux and the control flux. Such magnetic circuit schemes are used, for example, in high-current relays REP32, REP33, REP42, REP43 (for rated currents up to 100 A) developed earlier (before 2000) at the VNIIR of Cheboksary, and new (developed after 2000) REP78 - for rated currents up to 150 A. Relays previously developed by VNIIR in sealed design (for rated currents up to 100 A) REP13-220, REP13-330, REP14-28, REP14-31, where instead of a magnetically conductive stop there is a second П -shaped magnetic circuit with a winding. In this case, the circuit of the magnetic circuit is converted into differential (parallel). The armature travels of all the aforementioned relays are also within 1.5–2.3 mm.

As a prototype, we take the most stable batch magnetic relay system REP33-200 TU 3425-040-0216823-95 (Fig. 3a, 3b and 5a), also described in [6]. The design of the REP33 magnetic system is simple, has a relatively small size and weight, and has a fairly high sensitivity. The magnetic system of these relays has a sequential magnetic circuit consisting of a magnetic circuit with a winding, a rotary armature with a permanent magnet and pole pieces. The anchor of these relays contains a modern highly coercive magnet made of neodymium-iron-boron material. The polarizing flux Φ _{n of the} permanent magnet closes through the pole pieces of the armature and the magnetic circuit, creating holding forces and forming a sequential magnetic circuit with the control flux Φ _y .

The main disadvantages of the magnetic system of the known solutions are:

1. The need to use a magnetic guide to hold the armature in the actuated position (to provide a second stable position of the armature).

2. The inability to increase the working stroke of the anchor, because With the removal of the anchor from the poles of the magnetic circuit, the polarizing flux Ф _p passing through the magnetic circuit weakens and the anchor loses its ability to self-return, and the presence of a holding magnet-conducting plate further reduces the polarizing flux Ф _p through the magnetic circuit and sharply increases the ampere-control turns.

3. A large (doubled, with respect to the cross-section necessary for conducting the polarizing flux _{f p} ) cross-section of the magnetic circuit, because when the anchor is attracted to the cores (when returning), it is necessary to ensure the passage through the magnetic circuit of two according to the directed flows, Ф _п and Ф _у - control and polarizing.

4. Dependence of ampere-turns of operation on the size of the working gap (armature travel). This disadvantage is inherent in all known polarized bistable magnetic systems.

5. Long paths for the passage of magnetic fluxes (long cores, transient resistances in connections with the yoke) increase the magnetic resistance of the circuit, and, accordingly, reduce the holding force of the armature in a closed system, require large ampere turns to create a control flow.

6. Insufficient resistance to external mechanical stress, because the anchor is not balanced with respect to the axis of rotation. The side of the armature, free from poles and magnet, is to some extent balanced by the moving part of the contact system.

7. The high complexity of manufacturing, assembling and adjusting the fit of the anchor.

The aim of the invention is to increase the working stroke of the armature and torque throughout the stroke, increasing the efficiency of using a permanent magnet, expanding the scope of polarized magnetic systems, as well as eliminating the known disadvantages mentioned above inherent in most previously developed permanent magnet switching products.

The technical result of the proposed technical solution is to increase the working stroke of the armature and torque throughout the stroke, reducing the cross-section of the magnetic circuit, increasing the stability of ampere-turns of operation, increasing the efficiency of the magnet and the control circuit, increasing resistance to external mechanical influences, reducing the dimensions and weight of the device, facilitating the process of assembling and adjusting the anchor.

The specified technical result is achieved by the fact that in a polarized two-stable long-stroke electromagnet with a double sequential magnetic circuit containing a rotary armature with a permanent magnet and pole pieces, a magnetic circuit with a winding forming a closed sequential magnetic circuit, an additional permanent magnet with pole pieces is inserted into the rotary armature the magnets are magnetized in different directions, are equidistant and parallel to the axis of rotation of the pair Along with the winding located on the middle part of the H-shaped magnetic circuit, the armature is drawn only to one of the sides of the H-shaped magnetic circuit, with the possibility of creating one of two stable positions, in each of which the flux of one of the magnets is closed to one of the H sides -shaped magnetic circuit, forming a closed sequential magnetic circuit with it, the pole tips of the armature contain their own axis of rotation and are made with the ability to self-install on the poles of the magnetic circuit in the final positions, standing These magnets with pole tips are located on the armature frame equidistantly and parallel to its ends and are fixed together by a springy non-magnetic bracket, the armature and the magnetic circuit are connected by plates with longitudinal grooves in the attachment points with the possibility of adjusting the value of the armature stroke.

The essence of the proposed technical solution is that:

1. Structurally symmetric anchor with two permanent magnets has two stable positions due to the location of the axis of rotation parallel to the middle part of the H-shaped magnetic circuit, and the possibility of rotation and closure only on one of its sides, limiting its further movement in order to eliminate the magnetic conductive stop.

2. The anchor contains two permanent magnets with pole tips, the polarizing fluxes of which interact with the control flux throughout the course, and when the interaction of the control flux with one of the polarizing fluxes is weakened, the interaction with the other increases. Thus, to create the moment of rotation at the anchor, simultaneously and consistently attracting and repulsive forces are used to increase the course of the armature and increase its moment of rotation.

3. In the magnetic system, in order to reduce the cross section of the magnetic circuit, when triggered, only the oncoming control flux Ф _{у is used} . The necessary cross section of the magnetic circuit for conducting the control flux Ф _у is equal to the cross section necessary for conducting the polarizing flux Ф _p , because the total value of the counter flows in the serial circuit of the magnetic circuit at any moment of time cannot exceed the value of the polarizing flux Ф _п (just like the liquid does not flow through one pipe in different directions).

4. In the proposed technical solution, there are no working gaps at the initial moment, before starting, because the anchor is short-circuited on one of the sides of the H-shaped magnetic circuit, and appears already in the process of operation, after the anchor is torn off from the stops (poles) of the magnetic circuit. Moreover, the beginning of the movement of the armature occurs at the moment of comparing Ф _п and Ф _{at the} polarizing and control flows. Eliminating the dependence of the ampere-turns of starting on the size of the working clearances allows to increase (adjust) the working stroke of the armature without changing the parameters of the control circuit.

5. The winding is located on the middle part of the H-shaped magnetic circuit, which significantly reduced the length of the magnetic paths in the system and reduced the mass of the pole pieces of the armature, increased the efficiency of the permanent magnets and the control flux, and reduced the dimensions of the magnet and the volume of the winding.

6. The anchor is made completely symmetrical relative to the axis of rotation and structurally balanced in order to increase resistance to external mechanical stress.

7. The pole pieces of the armature have rotation axes, providing a spontaneous fit to the ends of the magnetic circuit, excluding the operation of adjusting the fit of the pole pieces of the armature to the ends of the magnetic circuit. In the design of the anchor, welding, high-temperature soldering and fitting of magnets are also completely excluded. In order to simplify the technology of assembly and adjustment of the armature, the pole pieces with a magnet are fixed with a spring clip made of non-magnetic material.

The invention is illustrated by images, where:

in FIG. 1 is a diagram of a known magnetic system with a sequential magnetic circuit and a “passive” armature: a) the direction Ф _у to operate; b) the direction of F _y to return;

in FIG. 2 is a diagram of a known magnetic system with a sequential magnetic circuit and an “active” armature: a) the direction Ф _у to operate; b) Ф _у = 0, the anchor returns due to Ф _п ;

in FIG. 3 is a diagram of a known magnetic system with a sequential magnetic circuit and an “active” armature and a magnetic focus: a) the direction Ф _у to operate; b) the direction of F _y to return the anchor;

FIG. 4 is a diagram of a polarized bi-stable long-stroke magnetic system with a double sequential magnetic circuit;

FIG. 5 -

a) the well-known REP33-200 relay (prototype), the dimensions of the magnet (5X12) X7 mm, the arm travel 2.1 mm;

b) - a prototype of the inventive magnetic system, the dimensions of the magnet (4X7) X8 mm, the working stroke of the anchor 6 mm;

c) - a prototype of the magnetic system, the dimensions of the magnet (4X7) X4 mm, the arm travel 6 mm;

FIG. 6 is a design of a magnetic system of a polarized bi-stable long-stroke electromagnet with a double sequential magnetic circuit.

In FIG. 6 the following notation is accepted:

1 - permanent magnet (2 pcs.);

2 - pole lugs (4 pcs.);

3 - axis of rotation of the anchor;

4 - winding of an electromagnet;

5 - core (middle part of the H-shaped magnetic circuit);

6 - side walls (sides) of the H-shaped magnetic circuit;

7 - axis of rotation of the pole pieces (4 pcs.);

8 - plates of the axis of rotation of the armature and adjustment of the stroke value (2 pcs.);

9 - a longitudinal groove in the plate of the axis of rotation of the armature and adjust the stroke;

10 - screws for fastening the plate of the axis of rotation of the armature and stroke adjustment (2 pcs);

11 - bracket (frame) of the anchor;

12 - bracket fixing magnets with pole pieces (2 pcs.).

A polarized electromagnet contains a rotary armature, two permanent magnets 1 with pole tips 2 magnetized in different directions, an H-shaped magnetic circuit with a winding 4 located on the middle part 5 of the magnetic circuit.

An H-shaped magnetic circuit is formed by side walls 6 with through holes for installing the core 5 with a winding 4. The side walls are parallel to each other, the core is perpendicular to them, together with the armature they form one of two closed sequential magnetic circuits.

Plate 8 is fixed on the magnetic circuit with screws 10, which serve to fasten the axis of rotation 3 of the armature and connect the armature and the H-shaped magnetic circuit, and, thanks to the longitudinal grooves 9, it is possible to adjust the value of the armature stroke. Setting the required armature travel and fixing the position of the plates 8 is done with two screws 10.

Permanent magnets 1 are made of rectangular cross section from a highly coercive neodymium-iron-boron material and magnetized in different directions. The magnets 1 and the pole pieces 2 are fixed to each other by a spring clip 12 made of non-magnetic material. Permanent magnets 1 are located together with the pole pieces 2 on the bracket / frame / frame of the armature 11, equally spaced and parallel to the ends of the bracket / frame / frame 11 and the axis of rotation of the armature 3, which in turn are parallel to the winding 4 located on the middle part of the H-shaped magnetic circuit 5, and are connected using the rotation axes 7. The rotation axes of the pole pieces 7 are necessary for self-installation of the pole pieces 2 on the poles of the side walls of the magnetic circuit 6 in the final positions when the armature is in one of two stable positions, forming one Well, from two possible closed sequential magnetic circuits.

A polarized two-stable long-path electromagnet with a dual serial magnetic circuit operates as follows.

Real samples of the claimed invention (Fig. 5b and 5c) were made in the embodiment with a rotary anchor. For convenience of description of the principle of operation, the magnetic system will be considered in the embodiment with a linear anchor shown in FIG. 4. The upper and lower parts of the anchor are rigidly connected, and the anchor can move longitudinally either up or down relative to the ends of the H-shaped magnetic circuit.

When the control flux Ф _у created by ampere-turns of the winding W located on the core (in the middle part of the H-shaped magnetic circuit) appears in the magnetic circuit:

- in the lower part of the magnetic system at the points of contact of the pole pieces of the armature to the ends of the magnetic circuit, the fluxes Ф _п1 and Ф _{у are} compensated, and the forces holding the armature first weaken, and when gaps δ ₁ and δ ₂ (the moment of separation of the armature) appear, counter-directed flows Ф _п1 and f _y form forces repelling the anchor.

- at the same time, in the upper part of the magnetic system, part of the polarizing flux Ф _{п2 is} displaced by the counter-directed control flux Ф _у from zone 2 to zone 1, the other part of the polarizing flux Ф _{п2 is} connected in gaps δ ₃ and δ ₄ into a serial circuit with the control flux Ф _y , creating an attractive force. In zone 1, the flows are in the opposite direction; therefore, the control flow Ф _у does not pass here. As the armature moves and approaches the ends of the magnetic circuit, the entire polarizing flux Ф _п2 from zone 1 passes to the magnetic circuit through the gaps δ ₃ and δ ₄ and at the end of the course is completely connected (closed) in a serial magnetic circuit with the control flux Ф _у . The anchor moves to another stable position. The magnetic system has complete symmetry about the axis of the winding. Therefore, the armature returns to its original position as described, when applying reverse polarity voltage to the winding, or a second winding for return can be provided in the design.

A double sequential magnetic circuit allows you to transmit to the anchor for the formation of the moment of rotation (or longitudinal displacement) at the same time two coordinated forces - pulling on one side and pushing away on the other. This fact allows you to increase the moment of rotation (or the force of movement) of the armature throughout the course, because with a decrease in the repulsive force on the one hand, the attractive force on the other increases. The flow Ф _у actively interacts with the flows Ф _п1 and Ф _п2 throughout the entire course. The anchor is “active” throughout the entire course, which allows to significantly increase the stroke in comparison with the prototype without changing the ampere-turns of operation.

With approximately the same separation forces generated by the magnet in the closed state of the armature, one can compare some parameters of the electromagnets of the prototype and the proposed technical solution, presented in table 1.

Thus, the removal of the magnetically conductive stop is due to the design features of the electromagnet, since the anchor is symmetrical with two permanent magnets, fixed to the magnetic circuit using the axis of rotation parallel to the middle part of the H-shaped magnetic circuit, while having two stable positions restricting its movement.

The decrease in the cross section of the magnetic circuit is determined by the fact that when triggered, only the oncoming control flow is used.

The decrease in weight and size parameters is significantly influenced by the fact that an increase in the working walking armature is carried out without changing the parameters of the control circuit, that is, without increasing the ampere-turns of operation (pulling), and therefore, the volume of the winding. The control winding itself is located on the middle part of the H-shaped magnetic circuit, it is common for two magnetic sequential circuits, the control flow of which passes through two consecutive magnetic circuits depending on the position of the armature, which significantly affects the overall dimensions, since the control winding is excluded for one from consecutive chains.

Resistance to external mechanical influences is due to the fact that the anchor is made completely symmetrical about the axis of rotation and structurally balanced.

The spontaneous adherence of the pole pieces of the armature to the ends of the magnetic circuit, the fixation of the pole pieces with a magnet with a spring clip made of non-magnetic material greatly facilitate the process of adjustment and assembly of the invention as a whole, since the operations of adjusting the fit, welding, high-temperature soldering and fitting of magnets are excluded.

An increase in the course of the anchor is achieved through the use of simultaneously and consistently attracting and repulsive forces. The adjustment of the stroke value itself is carried out using a plate with a longitudinal groove and screws for fastening the plate to the magnetic core of the electromagnet.

The use of this magnetic system is equally effective in designing both high-current contactors or relays, and miniature devices with a large armature stroke, which allows to significantly increase the switching power at high voltages in the small dimensions of the product. The presence of large values of the armature stroke allows applying the principle of self-locking control circuits in the apparatus design, when the control circuit breaks with its own contact in the final stage of the armature movement. The windings in such structures are always de-energized in static modes, and therefore are not heated, which allows the use of forced control modes, which means that they can be placed in much smaller volumes, which additionally leads to a decrease in the dimensions and mass of the entire electromagnet structure.

Information sources:

1. Gordon A.V. Polarized Electromagnets [Text] / А.V. Gordon, A.G. Slivinskaya - M .: Energy, 1964. - S. 13.

2. Royzen V.Z. Small-sized polarized relays and remote switches [Text] / V.Z. Royzen - L .: Energoatomizdat. Leningra. Department, 1969 .-- S. 5-6.

3. Slivinskaya A.G. Electromagnets and permanent magnets [Text] / A.G. Slivinskaya - M.: Energy, 1972. - S. 178.

4. Royzen V.Z. Small-sized electromagnetic relays [Text] / V.Z. Royzen - L .: Energoatomizdat. Leningra. Otdel, 1986.- S. 15.

5. Fundamentals of the theory of electrical apparatus [Text] / [B.K. Bul] Ed. G.V. Butkevich - M.: Higher School, 1970. - S. 298-303.

6. Ivanov I.P. Questions of the general theory and practice of designing polarized electromagnets [Text] / I.P. Ivanov, E.V. Sagaradze, G.P. Lead // University News, Ser. Electromechanics, - Volume 60. - 2017. - No. 2. - S. 44-49.

7. Trofimov E.Yu. On the issue of developing an independent release [Text] / E.Yu. Trofimov, A.G. Pechnikov // Transactions of the Academy of Electrotechnical Sciences of the Chuvash Republic - 2008. - No. 1. - S. 82-88, - ISBN 5-94794-001-9.

Claims (2)

1. A polarized bi-stable long-path electromagnet with a double sequential magnetic circuit, comprising a rotary armature with a permanent magnet and pole pieces, a magnetic circuit with a winding forming a closed sequential magnetic circuit, characterized in that an additional permanent magnet with pole pieces is inserted into the rotary armature magnetized in different directions, located equidistant and parallel to the axis of rotation, located parallel to the winding, located on the middle part of the H-shaped magnetic circuit, the armature is drawn only to one of the sides of the H-shaped magnetic circuit with the possibility of creating one of two stable positions, in each of which the flux of one of the magnets is closed to one of the sides of the H-shaped magnetic circuit, forming with a closed sequential magnetic circuit, the pole tips of the armature contain their own axis of rotation and are made with the possibility of self-installation on the poles of the magnetic circuit in the final positions, permanent magnets with pole tips ikami arranged on the frame anchors equidistantly and parallel to its ends and secured between a spring nonmagnetic brace anchor and magnetically connected plates with longitudinal grooves in the attachment points with the possibility of adjusting the magnitude of the armature stroke. 2. A polarized bi-stable long-stroke electromagnet with a double sequential magnetic circuit according to claim 1, characterized in that the anchor is made linear.

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