SU1534643A1 - Method of manufacturing electrical machine stator - Google Patents

Abstract

This invention relates to electrical engineering, in particular to electrical engineering technology. The purpose of the invention is to increase productivity. For this, the sheets of the stator magnetic circuit are stamped with an annular curvature having the shape of an isosceles trapezoid in cross section. The choice of the gap between the housing and the stator core assembled from the sheets and the tension is carried out by axially crimping the core after it is installed in the housing. The length of the side walls A and the height H of the said isosceles trapezium are determined by the formulas A = 1/4 (δ _g + δ _n + δ ₀ ), H = 1/4 (√ _g (δ _g + δ _n + δ ₀ ) ² - δ _z , where δ ₃ - the size of the gap between the core and the body

δ _n - required tension value when assembling a core with a housing

δ ₀ is a part of the perimeter of the flexure cross section, passing into the deformation of the core hole when the body is assembled with the core. 4 il.

Description

nick and body; OH - the required value of tension ha

at assembly of the core with the case;

 - a part of the perimeter of the cross-section of the bend, passing into the deformation of the hole in the core when the body is assembled with the core.

Then manufacture and assembly of the stator core with the housing is carried out. By axially crimping the core.

Stamp for the manufacture of a sheet of stator core with annular bending

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the ability of the liver to move the head 18 relative to the carriage 17 with the clamp 19. The press also includes a carriage guide 21, a carriage actuator hydraulic cylinder 22, a pressing head actuator hydraulic cylinder 23 and a hydraulic system (not shown). The expansion mandrel 14 includes a housing 24, sectors 25, a wedge 26, spring rings 27, a wedge drive cylinder (not shown). The sectors 25 are made of a material having a hardness greater than that of the stator core material and the housing 15, in order to limit the radial deformation of the core hole.

The method is carried out as follows.

The dimensions of the annular flexure and the diameter of the fox and the stator core are preliminarily determined after stamping. The size of the gap Ј. between the core and the housing, the Enough is sufficient for conveniently placing the housing on the stator core when installed on the press (Fig. 4) and not smaller than the tolerance for the internal diameter of the housing in order to prevent friction on the outer surface of the core. For example, the size of the gap is set to about 4 mm. The magnitude of the tension is set according to the working drawings of the electric machine, for example, for AIM 225M-2p $ 65 0.265 mm electric motors. Since axial compression of the core on the surface of the annular flexure, part of the length of the lateral side of the flexure trapezium is used to provide the required tension Ha and in conjugation of the core with the body in the magnitude of the side and trapezium include this amount of deformation from

&.

versity of the core -t u ()

The value 00 is determined by calculation based on the material properties of the stator core and the housing and their geometrical dimensions.

After punching, the outer diameter D1 (Fig. I) of the core sheet is set to a smaller stator diameter of the same standard size, produced without bending, by 85 and the inner diameter of the sheet — larger than the corresponding internal diameter by 00. Therefore, the value from side projection a on base

1 Ј t Oh, after which

S,

trapezoid is equal to c4 ° 9

at previously determined values of and e, 8h and and o determine the value of h.

An annular flexure is made on an annular portion of a sheet of core of width e, limited by the diameters of the bottom of the groove for the winding and the bottom of the stamping for the bracket (or welding). Therefore, the value f of the larger trapezium base (Fig. 2) is set smaller than e.

Then, stamping of the stator core sheets is carried out with the manufacture of an annular curvature, for example, on an A-6032 press. Here, a combined action stamp is used, the schematic diagram of which is shown in FIG. 3. When the plate 3 punch moves down, the upper pullers 8 and 9 press the stamped strip 12 against the working surface of the punch die.

g I, after which the moving die-cut matrix 4, the penetrative punch 5 and the punches for cutting the grooves simultaneously simultaneously cut the outer diameter of the core sheet,

5 billet rotor and grooves under the winding. Thereafter, at the end of the stroke of the plate 3, the annular punch 10, being inserted into the core sheet being manufactured, presses it at the contact point into the annular groove on the working surface of the die 1, whereby the required annular bend on the core sheet and the outer diameter sheet is reduced by $ 3. The required flexing force is preset by selecting the stiffness of the elastic ring (or spring) 11.

After the sheets are manufactured, the stator core is annealed and oxidized according to the existing technology. Then the sheets are mixed into a bag, pressed together and fastened with staples or by welding. When pressing the package, a pressing head is used, on the working surface of which there is an annular protrusion identical in shape and size to an annular bending on the core sheet. Accordingly, on the working surface of the press table on which the core is installed, there is an annular groove, identical in shape and size to an annular flexure of the core sheet.

After fabrication, the core 16 is mounted on the mandrel 14 of the press for assembling the housing with the stator core (FIG. 4). On the base of the 13 press set and center on

0, the lock wedge 26 of the mandrel is moved to its highest position by a hydraulic cylinder (not shown), and the mandrel sectors 25 move in the radial direction, the stator core is centered. Wedge 26 is fixed in this position, for example, using a hydraulic lock (not shown). After that from the hydraulic system serves

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fluid into the piston cavity of the hydraulic cylinder 22, the rod of which lowers the carriage 17. The carriage and the clamp 19 which is rigidly connected with it presses the core 16 to the base 13. Then, without removing the force from the hydraulic cylinder 22, the working fluid is fed into the piston cavity of the hydraulic cylinder 23, into as a result, the pressing head 18 produces axial compression of the core 16 along the surface of the annular bend. In this case, the flexure height h decreases, and the outer diameter of the core increases, i.e. there is a radial distribution of the core in outer diameter. Autumnal compression of the core is carried out until complete bending along the entire length of the core. This achieves obtaining the required tension in conjugation of the housing 15 with the core 16, as well as obtaining the fill factor in the zone where the bend was previously located equal to the fill factor in the remaining regions of the core volume. The force on the rod of the hydraulic cylinder 23 is set sufficient to eliminate buckling, and the force on the rod of the hydraulic cylinder 22 is sufficient to prevent rotation of the surface of the end face of the core, not in contact with the working surface of the pressing head 18, and to prevent folding in these areas. After assembling the housing with the core, the mandrel wedge 26 is brought to its lowest position, while under the action of the spring rings 27, the sectors 25 move in the radial direction, freeing the hole of the core. The working fluid is supplied to the vacuum chambers of the hydraulic cylinders 22 and 23. The carriage 17 and the pressing head 18 are raised to the extreme upper position, the stator is removed from the base 13 of the press.

Then, according to the existing technology, the stator core hole is machined (for example, by boring or piercing) to eliminate the combing and elliptical character of the hole, after which the winding is placed into the core grooves and impregnated (for example, by the drip impregnation method). The stator nick is finished.

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Claims (1)

Thus, the invention makes it possible to exclude from the technological process an operation of heating the body, the duration of which is very long, and the time required for cooling the body, and at the same time significantly reducing the piece time of the body assembly operation with the stator core by reducing the movement of the pressing head ( which in the proposed method is equal to the value of h). Therefore, since the duration of the remaining operations of the stator manufacturing process (sheet punching, core assembly, etc.) in the proposed method does not increase compared with the existing technology, it allows to significantly increase labor productivity. Invention Formula A method of manufacturing an electric machine stator, according to which the stator core sheets are stamped, the core is assembled and installed into the housing with a gap, moving the mating surfaces of the core and the housing to choose a gap between them in tension, characterized in that labor, the sheets are stamped with an annular bend, having the shape of an isosceles trapezoid in cross section, and the selection of the gap in the tension g is carried out by axially crimping the core after installing it into the body, that the length of the side walls and a height h of an isosceles trapezoid is defined from expressions 14 a-, + & -4 45 h- jUtfj + u. + U -fi five Where 0 8, SH- Ј „5 the size of the gap between the core and the housing; the required tension value when assembling the core with the case; a portion of the perimeter of the flexure cross section, passing into the deformation of the core hole when the body is assembled with the core. 7 / cmesi eleven % zri 73 /////////// A V 22 z