RU2118825C1 - Moving-coil instrument element - Google Patents

Abstract

FIELD: instrumentation engineering. SUBSTANCE: moving- coil element has moving coil built up of three rectangular formers placed in same plane and carrying working winding 1. Coil is suspended from yoke 3 and placed in working gap 4 of magnetic system 5 with moving magnet 6. Stuck to sides of working winding 1 wound on central former 7 are two side formers 9. Their sides abutting against central former 7 are placed in working gap 4 of magnetic system 5. Two other sides of formers 9 are placed in additional gaps 10 of magnetic circuit 11. EFFECT: provision for damping not only torsional vibrations of moving element but also transverse ones. 4 dwg

Description

 The invention relates to instrumentation and can be used in resistant to mechanical stress electrical measuring devices.

 Known magnetoelectric measuring mechanisms equipped for damping transverse vibrations with liquid dampers [1].

 A serious drawback of such mechanisms is the wide scatter of the values of the degree of sedation due to the impossibility of installing stretch marks exactly in the center of the reservoir of the damper, the high complexity of the assembly and the low reliability of the measuring mechanism due to leakage or shaking of the liquid from the reservoir under mechanical stress.

 Also known are magnetoelectric measuring mechanisms comprising a frame with a winding placed in the working gap of the magnetic system with an intra-frame magnet having a through hole. The frame contains a working winding for generating torque and a short-circuited winding for damping torsional vibrations. To damp lateral vibrations, the working and short-circuited windings are wound on a figure-eight frame with elements located in the same plane, the frame elements corresponding to the upper and lower sides of the figure eight are placed in the working gap of the magnetic system, and the frame elements corresponding to the cross-shaped part of the figure eight are joined with the help of counter cuts made in them, they are electrically isolated from each other and placed in a through axial hole made in an intra-frame magnet [2].

 The disadvantage of this design is the complexity of manufacturing a frame in the form of a figure eight, as well as the complexity of its assembly with a magnetic system, due to the presence of a through axial hole in the inner frame core and the presence of an internal cross-shaped part of the frame.

 The complexity of the assembly lies in the fact that they take a piece of a flat ribbon of conductive material and insert it into the through axial hole of the intramrame core, thereby giving the ribbon a figure eight shape. Solder or weld the ends of the frame and only then fix the frame with a movable frame.

 The closest in technical essence are magnetoelectric measuring mechanisms containing dampers made of conductive material of a rectangular shape [3].

 The disadvantage of such magnetoelectric measuring mechanisms is the absence of damping of transverse vibrations, since the dampers specified in [3] do not create damping forces to damp transverse vibrations, but only absorb torsional vibrations. This is because the currents induced during transverse vibrations of the frame in its sides, located in the working gap of the magnetic system, are directed towards each other. The vibration resistance of magnetoelectric measuring mechanisms is determined mainly by resistance to transverse vibrations, since the problem of damping torsional vibrations is solved quite simply.

 The aim of the invention is the damping of transverse vibrations of the movable part of the electrical meter.

 This goal is achieved by the fact that in the magnetic circuit, concentric to the working gap towards the periphery of the magnetic circuit, two additional gaps are made, connected to the working gaps through grooves, and the movable system is made in the form of three rectangular frames located in the same plane and electrically isolated from each other, and the sides of the middle frame oriented along the axis of rotation and the sides of two side frames adjacent to them are located in the working gap of the magnetic system, and the other two sides are more cages, oriented along the axis of rotation, are placed in additional gaps of the magnetic circuit.

 The invention is illustrated in the drawings.

 In FIG. 1 shows a magnetoelectric measuring mechanism from above; in FIG. 2 is a sectional view of a magnetoelectric measuring mechanism in the plane of the axis of rotation; in FIG. 3 is a diagram of the occurrence of currents and forces in rectangular frames during torsional vibrations of a mobile system; in FIG. 4 is a diagram of the occurrence of currents and forces in rectangular frames during transverse vibrations of a moving system.

 The magnetoelectric measuring mechanism comprises a suspension frame in the form of three rectangular frames located in the same plane and electrically isolated from each other with a working winding 1, suspended on braces 2 in the holder 3 of the electrical measuring device and placed in the working gap 4 of the magnetic system 5 with an intra-frame magnet 6. Working the winding 1 is placed on the middle frame 7. To the sides of the working winding 1 placed on the middle frame 7, two side frames 9, p are glued using adhesives 8 (eg epoxy resin) By the way, the sides of two side frames adjacent to the middle frame 7 are located in the working gap 4 of the magnetic system, and the other two sides of the side frames oriented along the axis of rotation are placed in additional clearances 10 of the magnetic circuit 11. Additional clearances 10 are connected to the working gap 4 through grooves 12 and concentric with the working gap 4 towards the periphery of the magnetic circuit 11.

 Damping of transverse vibrations of the moving system is as follows.

возникают демпфирующие токи I $\genfrac{}{}{0ex}{}{\text{′}}{\text{д}}$ и I $\genfrac{}{}{0ex}{}{\text{″}}{\text{д}}$ , которые создают демпфирующие силы F $\genfrac{}{}{0ex}{}{\text{′}}{\text{д}}$ и F $\genfrac{}{}{0ex}{}{\text{″}}{\text{д}}$ , а в сторонах боковых каркасов возникают демпфирующие токи I_д, которые в свою очередь создают демпфирующие силы F_д.When the movable system (frame) moves in the direction indicated by arrow 13 (Fig. 4) in the direction of the frame 7 located in the working gap 4 of the magnetic system with induction

damping currents arise I $\genfrac{}{}{0ex}{}{\text{′}}{\text{d}}$ and I $\genfrac{}{}{0ex}{}{\text{″}}{\text{d}}$ that create damping forces F $\genfrac{}{}{0ex}{}{\text{′}}{\text{d}}$ and F $\genfrac{}{}{0ex}{}{\text{″}}{\text{d}}$ , and damping currents I _d arise in the sides of the side frames, which in turn create damping forces F _d .

а токи I $\genfrac{}{}{0ex}{}{\text{′}}{\text{д}}$ и I $\genfrac{}{}{0ex}{}{\text{″}}{\text{д}}$ направлены навстречу друг другу, то демпфирующие силы F $\genfrac{}{}{0ex}{}{\text{′}}{\text{д}}$ и F $\genfrac{}{}{0ex}{}{\text{″}}{\text{д}}$ компенсируют друг друга, т. е. суммарная демпфирующая сила будет равна нулю. Следовательно, демпфирование поперечных колебаний подвижной системы будет осуществляться лишь двумя боковыми каркасами 9, так как демпфирующие силы F_д возникают только в сторонах, находящихся в рабочем зазоре магнитной системы. Две другие стороны боковых каркасов 9, ориентированные вдоль оси вращения, помещены в дополнительные зазоры 10 магнитопровода 11 и демпфирующие силы в них не возникают.Since the sides of the middle frame 4, oriented along the axis of rotation, are located in the working gap of the magnetic system with induction

and currents I $\genfrac{}{}{0ex}{}{\text{′}}{\text{d}}$ and I $\genfrac{}{}{0ex}{}{\text{″}}{\text{d}}$ directed towards each other, then the damping forces F $\genfrac{}{}{0ex}{}{\text{′}}{\text{d}}$ and F $\genfrac{}{}{0ex}{}{\text{″}}{\text{d}}$ cancel each other, i.e., the total damping force will be zero. Therefore, the damping of the transverse vibrations of the moving system will be carried out only by two side frames 9, since the damping forces F _d arise only in the sides located in the working gap of the magnetic system. Two other sides of the side frames 9, oriented along the axis of rotation, are placed in additional gaps 10 of the magnetic circuit 11 and damping forces do not arise in them.

 Torsional vibration damping of the mobile system is shown in FIG. 3 and proceeds as follows.

, возникают демпфирующие токи I_д, I $\genfrac{}{}{0ex}{}{\text{′}}{\text{д}}$ и I $\genfrac{}{}{0ex}{}{\text{″}}{\text{д}}$ , которые создают демпфирующие силы F_д, F $\genfrac{}{}{0ex}{}{\text{′}}{\text{д}}$ и F $\genfrac{}{}{0ex}{}{\text{″}}{\text{д}}$ . Суммарная емпфирующая сила будет равна сумме трех сил F_д+F $\genfrac{}{}{0ex}{}{\text{′}}{\text{д}}$ +F $\genfrac{}{}{0ex}{}{\text{″}}{\text{д}}$ , то есть демпфирование крутильных колебаний осуществляется всеми тремя каркасами.When the frame of the device moves in the direction indicated by arrow 12, on the sides of the frame 4 and 9 located in the working gap 4 of the magnetic system with induction

damping currents arise I _d , I $\genfrac{}{}{0ex}{}{\text{′}}{\text{d}}$ and I $\genfrac{}{}{0ex}{}{\text{″}}{\text{d}}$ which create damping forces F _d , F $\genfrac{}{}{0ex}{}{\text{′}}{\text{d}}$ and F $\genfrac{}{}{0ex}{}{\text{″}}{\text{d}}$ . The total damping force will be equal to the sum of the three forces F _d + F $\genfrac{}{}{0ex}{}{\text{′}}{\text{d}}$ + F $\genfrac{}{}{0ex}{}{\text{″}}{\text{d}}$ , that is, damping of torsional vibrations is carried out by all three frames.

 If the settling time of the moving part is longer than the settling time of the specified TU, then the middle frame 4 must be made of non-conductive material or make the frame frameless. Then the role of the damper of lateral and torsional vibrations will be performed by the damper of lateral vibrations made of two side frames 9.

Thus, in the inventive device due to the occurrence of damping forces F _d acting on the side frames 9, damping of transverse vibrations of the movable system of the magnetoelectric measuring mechanism is achieved.

 The implementation of the inventive magnetoelectric measuring mechanism does not cause difficulties. Based on it, magnetoelectric measuring instruments of increased vibration resistance can be built.

 Sources of information.

 1. A.S. USSR N 104186 - publ. in B.I. N 9, 1956.

 2. A.S. USSR N 805774 - publ., 1980 - (prototype).

 3. Fremke A.V. "Electrical Measurements", L., Energy, 1973, p. 66 - 67.

Claims (1)

 A magnetoelectric measuring mechanism comprising a magnetic system with a magnetic circuit and an intra-frame magnet, a movable frame in the form of a rectangular frame with a working winding, the working sides of which are placed in the working gap of the magnetic system, characterized in that in the magnetic circuit concentrically to the working gap towards the periphery of the magnetic circuit, two additional the gap connected to the working gaps through the grooves, to the sides of the winding located in the working gap, glued two side rectangular frame for damping transverse vibrations so that the three frames are located in the same plane and are electrically isolated from each other, with the sides of the middle frame oriented along the axis of rotation and the adjacent sides of the two side frames located in the working gap of the magnetic system, and the other two sides of the side frames oriented along the axis of rotation are placed in additional clearances of the magnetic circuit.

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