RU2284624C1 - Permanent-magnet machine rotor - Google Patents

Abstract

FIELD: electrical engineering; rotors for motors, generators, various power installations such as power stations, welding units, mechanized tools, etc.

SUBSTANCE: proposed rotor designed for use in permanent-magnet machine incorporating flat permanent magnets and magnetic core stacks has nonmagnetic metal casing accommodating core stacks and poles made of magnetically soft metal sheet, as well as flat magnets disposed in nonmagnetic material parallelepiped-shaped holed open on one end so that at least magnets are fixed in these holes by means of easily curing material or by surface of part having temperature expansion compensating means joined to rotor; novelty is that stress concentrators of compensation means are uniformly offset on rotor ring circumference relative to fastening slots and semi-cylindrical depressions on circular surface, as well as relative to one another.

EFFECT: precluded shrinkage cracks in nonmagnetic material of rotor body at crystallization and deformation of its ring upon mechanical treatment.

4 cl, 6 dwg

Description

The invention relates to electrical engineering, mainly to the production of electric machines with flat permanent magnets, and in particular to the design of the rotor of these machines.

According to the EAPO patent No. 003746, Н 02 К 1/27, 29/08 for 2002, an electric machine with axial flow and a non-separable rotor containing flat permanent magnets located in its body made of fiber-reinforced plastic or fabric plastic, for example, duroplast, is known including fiberglass reinforcing bandage made of epoxy or imide resin.

The implementation of this rotor with permanent magnets geometrically closed in a plastic reinforced casing determines the restoration of the machine after the magnetic properties of the magnets are reduced only by replacing the integral rotor unit. In the application of the Russian Federation No. 2001126048, Н 02 К 21/23, 7/18 for 2003, a generator assembly with a drive ICE is described, the flywheel of which contains a stator and a rotor with permanent magnets, and in the application No. 2001126050, Н 02 К 1/27, 21 / 22 for 2003, the generator assembly has a rotor with axial pockets open on at least one side to accommodate type-setting magnetic elements.

The rotor of the electric machine according to the application No. 2001131390, Н 02 К 1/28, 21/12 and the electric machine according to the application No. 2001131389, Н 02 К 21/14, 1/28 contain a magnetic circuit with permanent magnets and pole pieces placed on it with a gap between them, in which are placed the holding elements in contact with the outer ribs of the pole pieces and magnets and fixing them in the rotor.

All known solutions have structural elements with different coefficients of linear expansion, which requires the introduction of special compensation tools in the design, complicating and increasing the cost of the product due to the increase in material consumption and labor intensity. For example, described in the application No. 2001123215, Н 02 К 5/02, 5/18 for 2003, the electric motor is equipped with compensation rings located on opposite ends and made of a material having the same linear expansion with the material of the motor housing.

The closest in technical essence to the claimed solution is a magnetoelectric machine described in the EAPO patent No. 001864 N 02 K 21/12, 1/27, 15/03, 15/14 for 2001. The rotor of this machine contains an annular magnetic package and pole pieces of soft magnetic material with flat permanent magnets and non-magnetic jumpers between them. The case of non-magnetic material is made with rectangular openings (pockets) open from at least one end of the rotor for placement of permanent magnets in them, which, after installation, are fixed in them with easily hardening material or are geometrically closed by the surface of parts interfaced with the end of the rotor, for example, a flywheel. Radial grooves evenly spaced around the circumference are made on the flange end face of the housing.

The presence of a package of magnetically soft iron in the rotor assembly in a case made of non-ferrous metal (zinc, aluminum or their alloy) in combination with the high temperature of pouring the melt into the mold due to the difference in linear expansion leads to uneven shrinkage and formation during melt crystallization or machining cracks in non-magnetic material. And after the rotor is removed from the mandrel after machining, the part ring deforms - its ovality appears, which is the reason for the rejection of parts ready for assembly.

This phenomenon is due to different stiffness of the rotor housing, weakened in three radial sections, evenly spaced around the circumference. Five concentrators are concentrated in each of them: short radial grooves of variable depth on the flange end with recesses on the circumferential surface of the shoulder, having a length from the outer side of the permanent magnet hole to the inner diameter of the ring, mounting grooves on the housing flange, half-cylindrical recesses on the outer circumferential surface of the ring rotors and long grooves on the opposite flange lateral end face of constant depth and width. This weakening of these sections by the listed hubs causes an arbitrary change in the diameters of the rotor ring, turning its circle into an ellipse due to a decrease in the stiffness of the rotor in these sections.

Thus, to prevent shrinkage cracks, the rotor must have a system of compensation elements in the structure, however, their placement in the mentioned planes leads to deformation of the rotor ring in a free state.

The invention solves the problem of eliminating the rejection of products after pouring, cooling and removing the rotors from the mold due to the appearance of shrinkage cracks and deformation of it. The essence of the invention lies in the fact that a magnetoelectric machine with a rotor containing flat permanent magnets in rectangular holes oriented parallel to the axis of the rotor, open from at least one end of the rotor with ring packages of magnetic circuit and pole tips of soft magnetic material placed in its body of non-magnetic material with fixing the magnets in the holes with easily hardening substance or closing the open side of the holes with the surface of the part mating with the rotor, the flywheel, for example p, its rotor is configured with a system compensating elements at the ends of the body, including - radial, evenly spaced circumferentially butt grooves circumferentially offset from a corresponding end of the fastening system of the grooves on the rotor flange and semi-cylindrical recesses on the circumferential surface of its ring.

The system of compensation elements consists of short radial grooves of variable depth at the flange end face and long radial grooves of the entire depth of the rotor ring of the constant depth at the end opposite the flange face, and these groove systems are located with an offset from the plane of the mounting grooves of the flange and half-cylindrical recesses on the outer the circumferential surface of the rotor ring, respectively, at 60 ° and 30 ° around the circumference of the corresponding end face.

The radial grooves at the ends of the rotor ring can be made with a variable depth in width, for example, 2 mm on the outer surface of the end face and 1 mm at the bottom of the groove.

The radial grooves made on the flange end from the inner circumferential surface of the rotor ring to the semicylindrical recess on the outer circumferential surface have a depth and width of 2-3 mm, respectively, half-cylindrical recesses have a diameter of 8-10 mm, and the length and width of the mounting grooves of the flange, respectively (5-6 ) × (6-8) mm, three radial grooves of variable depth on the opposite flange end are made with a width and length respectively (2-3) × (7-9) mm, the length and depth of the grooves on the outer circumferential surface of the shoulder is (7- 10) × (1.5-2) mm, and slots with an inclined and the walls on this shoulder have a width at the end of it of 7-9 mm.

The implementation of the system of the listed compensation elements eliminates the shrinkage cracking of the material of the rotor housing during casting and deformation of the ring after removal of the machined rotor from the mandrel, that is, the solution of the problem.

Figure 1 shows the end face of the rotor casing with long radial grooves of constant depth, figure 2 - flange end with open rectangular holes and short radial grooves of variable depth. Figures 3, 4 and 5 show a section through radial planes A-A, BB and B-B, respectively, passing through mounting grooves and half-cylindrical recesses, long radial grooves at the end of open holes and short radial grooves at the flange end. Figure 6 is a cross section of a known rotor ring with a similar plane GG passing through one plane for the said compensation elements in the known rotor housing, mounting grooves and half-cylindrical recesses of the ring.

The rotor housing 1 shown in FIG. 1 has a flange 2 with mounting grooves 3 on it, half-cylindrical recesses 4 on the circumferential surface of the housing and with radial grooves 5 on the flange end. At the opposite end of the housing, short radial grooves 6 are made with rectangular holes 7, recesses and grooves with inclined walls on the annular flange (Fig. 2). The recesses and grooves are not shown, as they are evenly spaced around the rim circumference and do not cause rotor ring deformations.

The claimed rotor operates in the generator in a manner known and described in the literature, magnets and rotor are installed in the product according to the technology known in electrical engineering. When pouring a melt of non-magnetic material into a mold and crystallizing it, the system of displaced elements aligns the ring stiffness around the circumference and stress in the material due to the difference in linear expansion, which eliminates shrinkage cracks and deformation of the housing ring after removal of the machined rotor from the mandrel.

The listed elements of the compensation system are performed simultaneously with the crystallization of a pressure-molded into the mold with the packages of the magnetic circuit and pole pieces installed in it, cut in the dies of the press production, which is possible in industrial production. The mechanical processing of rotors after crystallization, the assembly of rotors with permanent magnets installed in the holes in the product also confirm the industrial application of the proposed solution.

They also confirm the industrial application of the claimed solution, the materials necessary for the manufacture of the rotor are soft magnetic iron (Art. 2013), non-magnetic alloy and permanent magnets made of NLZh alloy.

Claims (4)

1. The rotor of a magnetoelectric machine, comprising a body of non-magnetic metal with packages of magnetic circuit and poles of sheet soft magnetic metal in it and flat magnets in parallelepiped openings in non-magnetic metal, open from one end, at least with the fixing of magnets in these holes easily hardening substance or the plane of the product part joined with the rotor with means of compensating thermal expansions, characterized in that the stress concentrators of the compensation means are uniformly offset around the circumference of the rotor ring relative to the mounting grooves, half-cylindrical recesses on the circumferential surface and each other. 2. The rotor according to claim 1, characterized in that the system of long radial grooves on the flange end of the magnetic circuit from the fixing magnetic circuit and pole of the brackets before pouring non-magnetic metal into the mold of the brackets is shifted around the circumference from the mounting grooves of the flange and half-cylindrical recesses by an angle of 60 °, a system of short grooves of variable depth at the opposite end of the rotor - at an angle of 30 °. 3. The rotor according to claim 1, characterized in that the radial grooves on the ends of the rotor have a depth-variable width, for example 2 mm on the surface of each end and 1 mm at the bottom of each groove. 4. The rotor according to claim 1, characterized in that the radial grooves on the flange end face with a width of 2-3 mm are made over the entire width of the rotor ring, the mounting grooves on the flange have a width and length respectively (5-6) × (6-8) mm and the semi-cylindrical grooves aligned with it on the circumferential surface of the ring are made with a diameter of 8-9 mm, the radial grooves of variable depth at the opposite flange end face are (2-3) × (7-9) mm, respectively, the recesses on the annular flange are 7-10 mm long have a depth of 1.5-2 mm, and grooves of variable width on it have a width on the end surface and on the bottom of the groove, respectively Actually (7-9) × 1.5 mm.

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