DE102022115983B4 - Motor rotor core structure - Google Patents

Abstract

The main technical feature of the core structure of the motor rotor according to the invention is that several spaced-apart through-hole-like spaces are arranged one after the other on the iron core of the rotor of a rotary motor along the circumferential direction, in which the axis of rotation of the motor serves as the center of the circle, the through-hole-like spaces forming barriers for the magnetic circuit of the Form rotor and at the same time serve to pass through a plurality of straight rod-shaped combination elements made of non-magnetically conductive material, the plurality of stacked silicon steel sheets forming the iron core being fastened by the combination elements in order to increase the overall rigidity of the iron core and reduce the risk of possible deformation or damage to the silicon steel sheets , caused by centrifugal force during high-speed rotation.

Description

Technical area

The present invention relates to engine technology and in particular to a core structure of the engine rotor.

State of the art

In order to suppress the tension of the rotor of a spindle motor caused by the centrifugal force during high-speed rotation, the laid-open publication US 2014 / 0 167 551 A1 by the shape of the magnetic barrier holes located on the sides of the magnetic slots of the rotor and by the smooth arcs located on the outer side walls of the magnetic barrier holes, the maximum stress caused by the centrifugal force is reduced in the narrowest area between this part and the outer annular surface of the rotor, so that the Rotor is limited to the narrowest area, even if this causes damage caused by stress concentration during high-speed rotation of the rotor. This can prevent the rotor from breaking off and flying to the stator side.

At the same time, in the disclosure document US 2014 / 0 167 551 A1 also clearly stated that it is not recommended to use through holes through the rotor through which the bolts pass and combine with them, as the through holes become new stress concentration points, reducing the strength of the rotor. As far as the spindle motor is concerned, the rigidity is increased by increasing the diameter of the spindle, so as to obtain the technical means of good machining accuracy, which also leads to a reduction in the thickness of the rotor element provided in the radial direction on the circumferential side of the spindle, so that it is difficult in this limited radial thickness range to provide the rotor with the above-mentioned through holes in order to use the inserted bolts for the firm connection between the silicon steel sheets of the iron core.

The publication DE 10 2019 135 896 A1 discloses a permanent magnet spindle motor with several magnet groups that have a special spatial configuration.

The publication CN 2 13 585 316 U shows a synchronous permanent magnet spindle rotor made from a stamped sheet metal.

The disclosure document DE 10 2017 217 937 A1 discloses a rotating electrical machine with a secondary element that is rotatably mounted relative to a primary element and has a recess in which a permanent magnet is attached. The publication CN 2 07 382 162 U discloses another synchronous permanent magnet spindle rotor made of a stamped sheet metal.

Task of the invention

It is the main object of the present invention to provide a core structure of the motor rotor through which the structural rigidity of the rotor core can be increased so that the motor rotor can particularly meet the requirements imposed on the high-speed rotation of a spindle motor.

To solve the above-mentioned objects, the present invention provides a core structure of the motor rotor. Its main technical feature is that several spaced-apart through-hole-like spaces are arranged one after the other on the iron core of the rotor of a rotary motor along the circumferential direction, in which the axis of rotation of the motor serves as the center of the circle, the through-hole-like spaces forming barriers for the magnetic circuit of the rotor and at the same time for Passing through a plurality of straight rod-shaped combination elements made of non-magnetically conductive material, the plurality of stacked silicon steel sheets forming the iron core being secured by the combination elements in order to increase the overall rigidity of the iron core and reduce the risk of possible deformation or damage to the silicon steel sheets caused by the centrifugal force caused by high speed rotation.

Furthermore, a respective through-hole-like space comprises a through-hole-like magnetic barrier space and a through-hole continuously connected to this magnetic barrier space, the respective through-hole-like spaces being located in the circumferential direction on two sides of the corresponding magnetic slots of the rotor core, the diameter of the circumference serving as a mirror axis for the on two Through-hole-like spaces located on the sides of a respective magnetic slot act and these are mirrored in pairs and are continuously connected to the corresponding magnetic slots by the corresponding magnetic barrier spaces.

Here, a respective magnetic barrier space is continuously connected through the corresponding first side to the corresponding adjacent magnetic slot and through the corresponding second side to the corresponding adjacent through hole, the inner diameter of the first side of a respective magnetic barrier space being larger than the inner diameter of the second side of the latter, wherein these magnetic barrier spaces with different inner diameters are located in the radial section of the circumference and whose specific shape can be a flat geometric shape, for example a triangular shape.

At the same time, the inner diameter of the second side of a respective magnetic barrier space is also smaller than the inner diameter of the corresponding through hole, so that the combination elements passed through the through holes are not displaced radially into the magnetic barrier spaces through the connecting sections between the magnetic barrier spaces and the through holes, in order to achieve the advantageous effect the limitation and positioning of the combination elements.

The inner diameter of a connecting portion between the corresponding magnetic barrier space and the corresponding magnetic slot is smaller than the inner diameter of the first side of the corresponding magnetic barrier space and is also smaller than the height of the corresponding magnetic slot in the radial circumferential direction, thereby ensuring that the magnetic slots in the magnetic slots embedded magnets are not moved through the connecting sections between the magnetic barrier spaces and the through holes into the magnetic barrier spaces, and thus the advantageous effect of limiting and positioning the magnets located in the magnetic slots is achieved.

Brief description of the drawings

• 1 shows a schematic perspective view of a preferred embodiment according to the present invention;
• 2 shows a sectional view of the preferred embodiment according to the present invention 1 ;
• 3 and 4 show enlarged views of the partial area K of 2 the preferred embodiment according to the present invention.

Detailed description of the exemplary embodiment

First of all, for the core structure of the motor rotor according to a preferred embodiment of the present invention described below, the rotor element of a spindle motor for high-speed rotation is used as an example. However, the part of the overall technology of the spindle motor which is not related to the technical features of the present invention will not be described in the following description. However, this omitted portion is part of the prior art known to one skilled in the art, and its omission does not affect the completeness of the essential technical features of the present invention.

It will be on the 1 and 2 Referenced. The core structure of the motor rotor (10) according to a preferred embodiment of the present invention primarily comprises an iron core (20), a plurality of hole-like magnetic slots (30), a plurality of paired magnetic barrier spaces (40), a plurality of through holes (50) and a plurality of combination elements (60).

The iron core (20) is an annular tubular object formed by coaxially, sequentially stacking a plurality of annular silicon steel sheets and having an inner annular surface (21) defined by the inner tube wall and an outer annular surface (22) defined by the outer tube wall has, wherein the inner annular surface (21) and the outer annular surface (22) are circular in radial section or, as in the present exemplary embodiment, by a plurality of first arches (221) and a plurality of second arches (222), which have two different radii and are arranged alternately one after the other and are connected to each other, can be formed, the center of curvature of the outer annular surface (22) being coaxial or parallel to the center of the circle of the inner annular surface (21).

The magnetic slots (30) pass through the iron core along the direction of the central axis of the inner ring surface (21) and are located between the inner ring surface (21) and the outer ring surface (22), whereby the magnets (not shown) pass through the hole spaces of the Magnetic slots (30) are recorded and positioned through the perforated walls of the magnetic slots (30) and can thus be closely embedded in the interior of the iron core (20). However, the specific shapes of the magnetic slots (30) are not described in detail in the description since they are not part of the technical features of the present invention.

The diameter of the inner ring surface (21) acts as a mirror axis for the magnetic barrier spaces (40) and these are mirrored in pairs and each adjoin two sides of the corresponding magnetic slot (30) and go along the parallel to the central axis of the inner ring surface (21). Direction through the hole-like structures of the iron core (20) and are each continuously connected via their first side (41) to the corresponding adjacent magnetic slot (30).

The through holes (50) pass through the iron core (20) along the central axis of the inner ring surface (21) and are each continuously connected in pairs to the second sides (42) of the corresponding paired magnetic barrier spaces (40) and adjoin them.

It will be on 4 Referenced. The combination elements (60) each have a straight rod-shaped rod body section (61) made of non-magnetically conductive material (such as stainless steel or aluminum) and are each passed through the corresponding through hole (50), with the two ends of a respective rod shaft coming from the end surfaces of the two Ends of the tubular shaft of the iron core (20) protrude and the two end sections (not shown) are located outside the two ends of the tubular shaft and are firmly connected to the two ends of the rod shaft of the corresponding rod body section (61). Accordingly, a force is applied to the silicon steel sheets to maintain the stacked state of the silicon steel sheets. By exploiting the physical property of non-magnetic conductivity, the hole-like spaces of the through holes (50) can continue to maintain their barrier effect on the magnetic circuit.

It will be on 3 Reference showing the spatial relationships between the magnetic slots (30), the magnetic barrier spaces (40) and the through holes (50). The magnetic barrier spaces (40) located on two sides of a respective magnetic slot (30) are each continuously connected to this magnetic slot (30) by a part of the corresponding first side (41), the inner diameter of this partial connection area (411) being smaller than the inner diameter the corresponding first page (41). At the same time, this magnetic barrier space (40) is connected through a part of the corresponding second side (42) to a part of a corresponding through hole (50) to each form a connecting channel (421), the inner diameter of the connecting channel being smaller than the inner diameter (D ) of the corresponding through hole (50). The difference in the inner diameter can prevent the magnets embedded in the magnetic slots (30) and those through the through holes ( 50) rod body sections (61) passed through are moved into the magnetic barrier spaces (40) after passing through the connecting areas (411) or the connecting channels (421).

In the present exemplary embodiment, the specific shape of a respective through hole (50) is circular in radial section and the cross-sectional shape of a corresponding rod body section (61) is a supplementary circle in the radial direction, whereby the peripheral wall of a respective rod body section (61) fits precisely on the wall of the corresponding through hole (50). can rest and thus the rod body sections (61) can be guided stably through the through holes (50). In other embodiments, the shapes of the through holes may differ from the planar geometric shapes of the present embodiment, i.e. H. they can be oval or polygonal, for example.

Furthermore, the shape of a respective magnetic barrier space (40) is triangular in radial section, with the first side of a respective triangle through the corresponding first side (41), the second side of a respective triangle through the inner perforated wall (21) located near the inner annular surface (21). 43) of the corresponding magnetic barrier space (40) and the third side of a respective triangle is defined by the outer perforated wall (44) of the corresponding magnetic barrier space (40) located near the outer annular surface (22), with a respective connecting channel (421) located within the area of the corresponding third page.

With the composition of the above components, in the core structure of the motor rotor (10), the combination elements (60) can be passed through the through holes (50) to achieve close combination and good fastening of the stacked silicon steel sheets and increase the rigidity of the iron core. At the same time, the magnetic barrier effect formed by the through holes (50) and the magnetic barrier spaces (40) is maintained because the combination elements (60) having non-magnetic properties are limited, so that the core structure of the motor rotor (10) limits both the strength of the iron core as well as the electromagnetic properties. This results in a significant improvement compared to the state of the art.

It will be on 3 Referenced. In order to obtain better mechanical properties of the core structure of the motor rotor (10), the present invention further studies the dimensions of the magnetic barrier spaces (40) and the through holes (50). The data shown in Table 1 below proves that the present invention has good performance in terms of safety factor compared to the prior art. Table 1 Parameters r X1 X2 X3 X4 X5 X6 X7 X8 X9 B(°) 160 170 170 170 170 170 170 170 170 C(°) 20 20 16 (min.) 30 20 20 20 20 20 α 6.04 6.04 6.04 6.04 1.89 (min.) 4.53 7.55 6.04 6.04 γ 13.02 13.02 13.02 13.02 13.02 13.02 13.02 11.32 (min.) 14.34 (max.) Safety factor 1.01 1.28 1.15 1.13 1.11 1.38 1.09 1.16 1.36

In the above table, B is the first included angle and is defined to be an included angle in the radial direction of the iron core (20) between the inner hole wall (43) of a respective magnetic barrier space and the inner one located near the inner annular surface (21). Slot wall surface (31) of the corresponding adjacent magnetic slot (30).

C is the second included angle and is defined to be an interior angle in the radial direction of the iron core (20) between the inner hole wall (43) and the corresponding outer hole wall (44) of a respective magnetic barrier space.

The magnetic barrier spaces (40) and the associated magnetic slots (30) meet the conditions 150° ≤ B ≤ 190° and 16° ≤ C ≤ 35°, whereby the through holes (50) have the formula (1): α = D/Ro × 100%, 1.9% ≤ α ≤ 10.1, where in the formula D is the diameter of a respective through hole (50) and Ro is the radius of a respective second arc (222).

wobei in der Formel F die Breite einer jeweiligen magnetischen Barriere ist, die bei den magnetischen Barriereräumen (40) und den mit diesen durchgängig verbundenen Durchgangslöchern (50) als der geradlinige Abstand zwischen einer jeweiligen ersten Seite (41) und dem Krümmungsmittelpunkt des entsprechenden Durchgangslochs (50) definiert ist, wobei Ro der Radius eines jeweiligen zweiten Bogens (222) ist.The magnetic barrier spaces (40) and the through holes (50) adjacent to them and continuously connected to them fulfill the following formula (II): $$\mathrm{\gamma }=\text{F/Ro}\times 100\text{\%}\text{,}11.3\text{\%}\le \mathrm{\gamma }\le 14.3\text{\%}$$

where in the formula F is the width of a respective magnetic barrier, which is the straight line in the magnetic barrier spaces (40) and the through holes (50) continuously connected to them Distance between a respective first side (41) and the center of curvature of the corresponding through hole (50) is defined, where Ro is the radius of a respective second arc (222).

As shown in Table 1, the safety factor can be effectively improved to more than 1.01 by the core structure of the motor rotor (10), which increases the rigidity of the iron core (20) during high-speed rotation, thereby reducing the risk of possible deformation or damage caused by the centrifugal force caused is minimized.

Reference symbol list

10

Motor rotor core structure

20

Iron core

21

inner ring surface

22

outer ring surface

221

first bow

222

second bow

30

Magnetic slot

40

magnetic barrier room

41

first page

411

Connection area

42

second page

421

connection channel

43

inner perforated wall

44

outer perforated wall

50

through hole

60

Combination element

61

Rod body section

b

first included angle

C

second included angle

D

Inner diameter of the through hole

F

Width of the magnetic barrier

Ro

Radius of the second arc

Claims (9)

A core structure of the motor rotor (10), comprising: an annular iron core (20) formed by coaxially sequentially stacking a plurality of annular silicon steel sheets and having an inner annular surface (21) and an outer annular surface (22), the outer annular surface (22 ) is formed by a plurality of first arches (221) and a plurality of second arches (222), which have two different radii and are arranged alternately one after the other and connected to one another; a plurality of magnetic slots (30), which are arranged at a distance from one another, are located between the inner annular surface (21) and the outer annular surface (22) of the iron core (20) and parallel to the center of curvature of the inner annular surface (21) axially through the iron core (20) go through; a plurality of paired through holes (50) passing axially through the iron core (20) parallel to the center of curvature of the inner annular surface (21) and spaced in the radial direction from two sides of the magnetic slots (30); a plurality of paired, hole-like magnetic barrier spaces (40), which extend along the axial direction parallel to the center of curvature of the inner annular surface (21) of the iron core (20) and pass through the iron core (20), the paired magnetic barrier spaces (40) between two sides of the corresponding magnetic slot (30) and the corresponding paired through holes (50) and through the corresponding first side (41) with the corresponding magnetic slot (30) and through the corresponding second side (42) with the corresponding through hole (50) are consistently connected; a plurality of rod-shaped combination elements (60), made of non-magnetically conductive material, passed through and fixed in the corresponding through holes (50) and exerting opposite forces on the two axial ends of the iron core (20) and acting on the stacked silicon steel sheets; wherein the wall of a respective through hole (50) rests on the peripheral surface of the combination element (60) passed through its hole space; wherein the inside diameter of a respective first side (41) is larger than the inside diameter of the corresponding second side (42); wherein the inside diameter of a respective first side (41) is larger than the inside diameter of the connection area between this first side (41) and the corresponding magnetic slot (30); and wherein the inner diameter of a respective channel through which the corresponding second side (42) and the corresponding through-hole (50) are connected to each other is smaller than the inner diameter of the corresponding through-hole (50). Core structure of the motor rotor (10). Claim 1 , in which the through holes (50) fulfill the following formula (I) and the magnetic barrier spaces (40) and the adjacent through holes (50) continuously connected to them fulfill the following formula (II): $$\mathrm{\alpha }=\text{D/Ro}\times 100\text{\%}\text{,}1.9\text{\%}\le \mathrm{\alpha }\le \text{10}\text{.1\%};$$

$$\mathrm{\gamma }=\text{F/Ro}\times 100\text{\%}\text{,}11.3\text{\%}\le \mathrm{\gamma }\le 14.3\text{\%};$$

where in the formulas D is the diameter of a respective through hole (50); Ro is the radius of a respective second arc (222); F is the straight-line distance between a first side (41) and the center of curvature of the corresponding through hole (50) in the magnetic barrier spaces (40) and the through holes (50) continuously connected to them. Core structure of the motor rotor (10). Claim 1 , in which the shape of a respective magnetic barrier space (40) is triangular, wherein the first side of a respective triangle is defined by the corresponding first side (41), the second side of a respective triangle by a corresponding inner perforated wall (43) and the third side of a respective triangle is defined by a corresponding outer hole wall (44), the position at which a respective through hole (50) is continuously connected to the corresponding magnetic barrier space (40) being within the area of the corresponding third side. Core structure of the motor rotor (10). Claim 1 , in which in the radial direction of the iron core (20) the internal angle (C) between the inner perforated wall (43) of a respective magnetic barrier space (40) located near the inner annular surface of the iron core and the outer perforated wall (40) located near the outer annular surface of the iron core 44) of this magnetic barrier space (40) is between 16° and 35°. Core structure of the motor rotor (10). Claim 1 , in which in the radial direction of the iron core (20) the internal angle (B) between the inner hole wall (43) of a respective magnetic barrier space (40) located near the inner annular surface of the iron core and the inner slot wall surface located near the inner annular surface (21). of the corresponding adjacent magnetic slot (30) is between 150° and 190°. Core structure of the motor rotor (10). Claim 1 , in which a respective combination element (60) has a straight rod-shaped rod body section (61) which is passed through the corresponding through hole (50), and two end sections which are located in the axial direction outside the two ends of the iron core, the end sections are firmly connected to the rod ends of the corresponding rod body section (61). Core structure of the motor rotor (10). Claim 1 , in which the radial section of a respective through hole (50) has the shape of a flat circular geometry. Core structure of the motor rotor (10). Claim 1 , in which the radial section of a respective through hole (50) has the shape of a flat elliptical geometry. Core structure of the motor rotor (10). Claim 1 , in which the radial section of a respective through hole (50) has the shape of a flat polygonal geometry.

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