RU2497218C1 - Winding method of solenoid of strong magnetic field - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: winding method of a solenoid involves winding of two unequal and insulated sections with a single wire - in the form of a multilayer solenoid and a flat spiral on one of the edges, saturation of the solenoid with binding dielectric composition, polymerisation, winding of solenoid surface with dielectric bandage with polymerisation. The above operations are performed on a setup fixed in a machine spindle and having a shaft with gaskets and a wire tensioning device. Prior to solenoid winding, a wire is wound off the coil with the length that is enough for winding of a flat spiral on outer surface of a pulley, and smooth transition of the wire to the setup shaft is provided through a composite gasket with curved surfaces. Winding of multilayer solenoid, saturation with binding dielectric composition with further polymerisation is performed individually for each layer. Then, the wire is wound of the pulley and to the coil with the wire, composite gasket is removed and winding of flat spiral is performed on the machine through the adjustable tensioning device. Curved surface of the composite gasket, which provides smooth transition of the wire from the pulley t the shaft, is made in the form of an Archimedean spiral between points of tangent to the pulley surface and tangent to the shaft axis surface, on which the multilayer solenoid is wound.

EFFECT: improving winding quality by winding a flat spiral with constant adjustable tension.

2 cl, 2 dwg

Description

Technical field

The invention relates to techniques for strong magnetic fields and can be used to create both static and pulsed devices.

State of the art

A known method of winding solenoids of strong pulsed magnetic fields [1], in which insulation is applied to a high-strength wire, for example, a Cu-Ag micro composite, and then the wire is wound on a mandrel in the form of a thick multilayer solenoid, possibly with a reinforcing dielectric thread, impregnated with an epoxy compound and fasten with an external bandage from a high-strength dielectric. The axial section of such a solenoid is a rectangle with the exception of the inner layer, which extends beyond the rectangle. In this case, the wire of the inner layer extends beyond the region of a strong magnetic field, which avoids strong mechanical stresses on the internal output of the solenoid. This winding method allows the manufacture of solenoids that repeatedly generate magnetic field pulses with a peak value of up to 58 T.

The disadvantages of this method include large dimensions, due to the elongated inner layer, the complex organization of axial compression.

The closest method for winding solenoids of strong pulsed magnetic fields, selected as a prototype, is the method described in [2]. The method includes winding in a single piece of wire two unequal and isolated sections, one of which is a conventional multilayer solenoid, and the other is a flat spiral at one of its ends. To prevent electrical breakdown, a 1 mm thick PCB gasket was placed between the sections. Such a two-section winding makes it possible to transfer both conductors to the outer layer of the solenoid, where the mechanical stress is much less. Inevitable in this case, the heterogeneity of the winding is specially shifted from the central plane, where the mechanical stresses are maximum, to one of the ends.

The wire was wound around a snap, which was a textolite gasket and two Teflon bushings mounted on a steel stud, one of which was screwed onto the stud, and the other had a loose fit. This design was necessary in order to remove the bushings after impregnation of the solenoid with epoxy compound. A pin (shaft) with bushings fixed on it was installed in the spindle of a lathe, on the support of which a device was mounted for tensioning and aligning the wire.

First, a piece of wire with a length of about 1 m is pulled through a slot in a textolite gasket and wound on an auxiliary bobbin, then a flat spiral is manually wound using this bobbin, the wire is led out through a slot in the cheek of the sleeve and fixed to a plate rigidly connected to the hairpin. Such fastening is necessary to prevent the sleeve from turning during winding. 0.5 mm thick fiberglass is wound in four layers along the lateral surface of a flat spiral, thereby ensuring reliable isolation of the spiral from the current lead of the second section. After this operation, a second section is wound - a conventional multilayer solenoid. When winding, the machine support along with the devices attached to it shifted to the right or left in proportion to the winding pitch, which ensured its high quality. The current lead of the second section also passed through the slot in the cheek of the sleeve: the slots for the conductors were spaced 90 degrees around the circumference of the cheek. Then the second section conductors are mounted together with the spiral conductors on the plate. The surface of the solenoid is wrapped in one layer with 0.5 mm thick fiberglass. The solenoid obtained in this way was placed in a cylindrical glass of tin, in which the impregnation was carried out in vacuum with an epoxy compound, polymerization occurred at a temperature of 80-90 degrees C for 36 hours. At the end of this process, the excess part of the compound was ground down to a layer of fiberglass. Then, the solenoid was wrapped on the outer surface with many layers of glass fiber, also impregnated with an epoxy compound, the polymerization of which occurred under the same conditions, forming a dielectric band. To prevent axial cracking, the dielectric band is pulled together with two 20 mm thick PCB flanges and four 12 mm stainless steel bolts.

The advantage of this method of winding is that both outputs of the solenoid are on the outside of the solenoid. Since maximum magnetic fields are created inside the solenoid, the inner layers experience the greatest mechanical deformation. The outer layers experience much weaker deformations; therefore, the location of the leads on the outer surface of the solenoid avoids their breakage.

The disadvantages of the prototype include a strong bend of the wire on the auxiliary bobbin. The winding of solenoids of strong magnetic fields is carried out by high-strength micro-composite wires of the type Cu-Nb, Cu-Ag, Cu-Ni ₃ Ti, which have stringent requirements for a minimum bending radius. The dimensions of the bobbin are determined by the minimum bending radius. Since the bobbin, when winding a flat spiral, moves around the axis of the solenoid, the winding device should have a large free space around the axis, i.e. large machine needed. In addition, when manually winding a flat spiral, it is impossible to provide the necessary constant tightness of the wire for its uniform, tight winding.

In this regard, the technical problem arises of reducing the dimensions of the solenoid winding machine while maintaining a large bending radius of the wire and improving the quality of the winding.

Disclosure of invention

The technical result of the proposed solution is to improve the quality of winding the solenoid by winding a flat spiral with a constant controlled tension.

The technical result of the proposed method for winding a solenoid of a strong magnetic field according to paragraph 1 is achieved by the fact that it includes winding a single wire of two unequal and isolated sections - in the form of a multilayer solenoid and a flat spiral at one of the ends, impregnation of the solenoid with a binder dielectric composition, polymerization, winding of the surface of the solenoid dielectric bandage with polymerization, which is carried out on a snap fastened in the machine spindle in the form of a shaft with gaskets and a device for tensioning the wire. In this case, before winding the solenoid, a wire with a length necessary for winding a flat spiral is unwound from the coil.

New in the method of winding a strong magnetic solenoid according to paragraph 1, is that a wire for winding a flat spiral is unwound from the coil onto the outer surface of the drum coaxial with the tool shaft, through a composite gasket with curved surfaces, ensuring a smooth transition of the wire to the tool shaft. The winding of a multilayer solenoid and impregnation with a binder dielectric composition followed by polymerization is carried out separately for each layer, then the wire is rewound from a drum to a coil with a wire, the composite gasket is removed and a flat spiral is wound on the machine through an adjustable tensioner. New in the method of winding a strong magnetic solenoid according to paragraph 2, is that the curved surface of the composite gasket, providing a smooth transition of the wire from the drum to the shaft, is made in the form of an Archimedean spiral between the points tangent to the surface of the drum and tangent to the surface of the shaft axis that is wound multi-layer solenoid.

Unwinding a wire for a flat spiral from a coil with a wire to the outer surface of the drum, coaxial with the tool shaft, and ensuring its smooth transition through a composite gasket with curved surfaces to the shaft, allows reducing the dimensions of the machine and maintaining a large bending radius of the wire.

Winding a multilayer solenoid and impregnating with a binder dielectric composition followed by polymerization, carried out separately for each layer, can improve the isolation of the inter-turn zone and increase the service life of the solenoid.

Rewinding the wire from the drum to the reel, removing the composite gasket and winding the flat spiral, carried out on the machine through an adjustable tensioner, allows for a more dense winding of the flat spiral and increase the service life of the solenoid.

Brief Description of the Drawings

The invention is illustrated by figures 1 and 2.

Figure 1 shows the equipment for winding a solenoid, where: 1 - machine spindle, 2 - bolt, 3 - textolite gasket, 3a - composite gasket with curved surfaces, 4 - shaft, 5 - fluoroplastic gasket, 6 - removable disk, 7 - a nut, 8 - the tailstock of the machine, 9 - a support of the machine, 10 - a coil with a wire, 11 - a device for tensioning and aligning the wire, 12 - an eject disk, 13 - a drum.

Figure 2 presents a view along aa of the construction of a composite gasket with curved surfaces 3a, where: 1 - liner, 2 - liner, 3 - drum, 4 - shaft.

The implementation of the invention

Equipment for winding a solenoid (Fig. 1), having a drum 13, a removable composite gasket with curved surfaces 3a, mounted on the end surface of the drum, fluoroplastic gaskets 5, removable 6 and ejector 12 disks are placed on the shaft 4, fastened with a nut 7 and installed in spindle of 1 machine. The end of the wire from the coil 10 is passed through a device for tensioning and aligning the wire 11 and fixed with a bolt 2 on the drum 13. A device for tensioning and aligning the wire 11, having an adjustable value of the tension of the wire, is mounted on the support 9 of the machine. On the shaft 4 snap is applied insulation from a PTFE film. The insulation of the shaft 4 with a fluoroplastic film and fluoroplastic gaskets 5 are used to enable the subsequent separation of the manufactured solenoid from the tooling. To form the space of the annular zone and ensure a smooth transition of the wire from the drum to the shaft 4, a removable composite gasket 3a in the form of inserts 1 and 2 is attached to the inner end of the drum 13 (Fig. 2). The curved surfaces of the removable composite gasket 3a, providing a smooth transition of the wire to the tool shaft, are made in the form of an Archimedean spiral between the points tangent to the surface of the drum 13 and tangent to the surface of the shaft axis 4, on which a multilayer solenoid is wound.

The method of winding solenoids of a strong magnetic field is implemented as follows.

When winding, the first 6 turns (about 1.5 m) are wound on the outer surface of the drum 13, and then the wire along the curved surface of the removable composite gasket 3a (Fig. 1) is moved to the shaft 4 and passed through the slot in the gasket 3.

Next, layer-by-layer winding of the solenoid is carried out with each layer impregnated with an epoxy composition, followed by drying for 24 hours. Layer-by-layer deposition of epoxy on the wire was used to improve the isolation of the inter-turn zone and give greater strength to the solenoid. After drying the last layer, the wire of the required length is cut off and fixed on the solenoid. Then remove the liners 1 and 2 (Fig. 2) of the composite gasket with curved surfaces 3a, forming an annular zone and providing a smooth transition of the wire to the shaft 4 snap. For winding the annular zone of the solenoid, the end of the wire is unfastened from the drum 13, fixed on the coil 10 and the wire is rewound onto it manually. The winding of the spiral of the annular zone is also carried out on the machine through an adjustable tensioning device. An epoxy compound is applied to the surface of the wire when winding the spiral, followed by its polymerization.

After drying, cut the wire of the required length and fix it on the solenoid. The drum is disconnected from the equipment for winding the solenoid, the ends of the wire are led out through the grooves in the gasket 5, the ejector disk 12, the flange of the shaft 4, are turned into coils and fixed on the machine chuck.

The company has implemented the claimed method of winding a solenoid of a strong magnetic field. The tests showed that, thanks to the winding of a part of the wire onto the tooling drum, the smooth transition of the wire from the drum to the tooling shaft and the winding of the main section of the solenoid and the ring spiral through an adjustable tensioner, the quality of the solenoid winding is improved and the service life of the solenoid is increased.

The positive results include the fact that the device for winding the solenoid is compact and did not require the use of a large-sized machine while maintaining a large bending radius of the wire, as well as providing a denser winding of the wire when winding a flat solenoid spiral.

The claimed invention can be used for the manufacture of solenoids for the purpose of their application in static and pulsed devices in the technique of strong magnetic fields.

Information sources

1. T. Asano, Y. Sakai, G. Kido, K. Inoe, H. Maeda. Development of wire wound pulsed magnet, Physica B, Vol. 211, p. 46, 1995.

2. Lagutin A.S., Ozhogin V.I. Strong pulsed magnetic fields in a physical experiment. M .: Energoatomizdat, 1988, p. 49, Fig. 2.29.

Claims (2)

1. The method of winding a solenoid of a strong magnetic field, including winding together a single wire of two unequal and isolated sections in the form of a multilayer solenoid and a flat spiral at one of the ends, impregnating the solenoid with a binder dielectric composition, polymerizing, wrapping the surface of the solenoid with a dielectric bandage with polymerization, which is carried out on a fixed in the machine’s spindle, a tool having a shaft with gaskets placed on it and a device for tensioning the wire, while before winding the solenoid, they are unwound from to a wire with a length necessary for winding a flat spiral, characterized in that the wire for winding a flat spiral is unwound from the coil onto the outer surface of the drum and through a composite gasket with curved surfaces provide a smooth transition of the wire to the tool shaft, and winding a multilayer solenoid, impregnating with a dielectric binder composition with subsequent polymerization is carried out separately for each layer, then from the drum the wire is rewound to a coil with a wire, the composite gasket is removed and They wind the flat spiral on the machine through an adjustable tensioner. 2. The method of winding a solenoid of a strong magnetic field according to claim 1, characterized in that the curved surface of the composite gasket, providing a smooth transition of the wire from the drum to the shaft, is performed in the form of an Archimedean spiral between points tangent to the surface of the drum and tangent to the surface of the shaft axis, on which is wound with a multilayer solenoid.

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