Rotor core structure of permanent magnet motor

Abstract

A permanent magnet motor rotor iron core structure comprises an iron core, the iron core is formed by stacking at least two first silicon steel sheets and at least two second silicon steel sheets in the axial direction, the bottom face of a groove of each first silicon steel sheet is connected with an elastic piece, and the outer end of each elastic piece extends towards the outer side of the corresponding groove; the height direction of the elastic piece is parallel to the depth direction of the groove, the width direction of the elastic piece is parallel to the length direction of the magnetic steel groove, the height of the elastic piece is larger than the depth of the groove, the difference between the height of the elastic piece and the depth of the groove is 0.1-0.3 mm, and the width of the elastic piece is more than two times of the thickness of the first silicon steel sheet. And the plurality of elastic sheets in the slot are uniformly distributed in the depth direction of the slot. According to the utility model, the grooves and the elastic sheets are arranged in the magnetic steel grooves, and the sizes and the distribution of the elastic sheets and the grooves are designed, so that when the magnetic steel is assembled in the slot, the magnetic steel can be firmly fixed in the slot by the elastic sheets, and the use of a traditional filler can be eliminated.

Description

Technical Field

[0001] The utility model relates to the field of machinery, in particular to a permanent magnet motor, and in particular to a permanent magnet motor rotor core structure. Background Art

[0002] Permanent magnet synchronous motors are divided into two types: surface-mounted and embedded, depending on the different ways in which the rotor magnets are installed and fixed. High-speed rotors used in new energy vehicles are mostly embedded rotors. In the prior art, the main way to fix the magnets in embedded rotors is to use fillers such as resins and adhesives to bond the magnets in the slots. The problems with this method are complex processes, low production efficiency, and high production costs. After aging and heating, the fillers are prone to lose their fixing effect, and there is a risk of the magnets loosening, and even reversely affecting the core laminations, making the motor unable to operate normally. In addition, the shrapnel-type structure in the prior art has a large plastic deformation after the shrapnel is assembled, which leads to insufficient holding force between the magnet iron core laminations, especially after durability, the magnets undergo a large displacement in the core. Summary of the invention

[0003] The utility model aims to provide a permanent magnet motor rotor core structure, which is intended to solve the technical problems in the prior art of weak fixation and easy loosening of magnetic steel and insufficient holding force between stacked magnetic steel cores.

[0004] The utility model discloses a permanent magnet motor rotor core structure, comprising an iron core, wherein the iron core is composed of at least two first silicon steel sheets and at least two second silicon steel sheets stacked in an axial direction, a plurality of magnetic steel slots are evenly distributed in any one of the first silicon steel sheets and the second silicon steel sheets along the circumferential direction, the magnetic steel slots of a plurality of first silicon steel sheets and the second silicon steel sheets are stacked to form a slot, a groove is arranged on the side of any one of the magnetic steel slots on the side close to the core axis, a spring is connected to the bottom surface of the groove of any one of the first silicon steel sheets, and the outer end of the spring extends to the outside of the groove; the depth direction of the groove and the length direction of the magnetic steel slot are both perpendicular to the core axis direction, the height direction of the spring is parallel to the depth direction of the groove, the width direction of the spring is parallel to the length direction of the magnetic steel slot, the height of the spring is greater than the depth of the groove, the difference between the height of the spring and the depth of the groove is 0.1-0.3mm, and the width of the spring is more than twice the thickness of the first silicon steel sheet.

[0005] Furthermore, the groove is arranged on the side of the magnetic steel slot close to the core axis.

[0006] Furthermore, the distance between the spring piece and the end face of the core is greater than or equal to 4 mm, the depth direction of the slot is parallel to the axial direction of the core, and the multiple spring pieces in the slot are evenly distributed in the depth direction of the slot.

[0007] Furthermore, a magnet is disposed in any slot, and any magnet is in contact with at least two spring sheets.

[0008] Furthermore, the width of the spring piece is greater than or equal to 0.6 mm.

[0009] Furthermore, both sides of the inner end of the spring piece are provided with rounded corners, and the radius of the rounded corners is greater than 0.3 mm.

[0010] Compared with the prior art, the utility model has a positive and obvious effect. The utility model sets grooves and springs in the magnetic steel slot, and designs the size and distribution of the springs and grooves, so that when the magnetic steel is assembled into the slot, the springs can firmly fix the magnetic steel in the slot, making it difficult for the magnetic steel to shift, reducing the risk of the magnetic steel loosening, and improving the life of the motor stator without damaging the magnetic steel. In this way, the use of traditional fillers can be eliminated, simplifying the production process, reducing material costs, and thus reducing the manufacturing cost of the entire motor. The raised springs apply a certain positive pressure to the magnetic steel, so that when the motor is working at high speed, the magnetic steel fixing structure is still stable and reliable, with high safety, meeting the use requirements of the new energy vehicle industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 The utility model is a three-dimensional schematic diagram of a permanent magnet motor rotor core structure.

[0012] Figure 2 for Figure 1 A partial enlarged schematic diagram of .

[0013] Figure 3 It is a front view schematic diagram of a permanent magnet motor rotor core structure of the utility model.

[0014] Figure 4 It is a front view schematic diagram of a first silicon steel sheet in a permanent magnet motor rotor core structure of the utility model.

[0015] Figure 5 It is a partial schematic diagram of a first silicon steel sheet in a permanent magnet motor rotor core structure of the utility model. DETAILED DESCRIPTION

[0016] The present invention is further described below in conjunction with an embodiment, but the present invention is not limited to the embodiment. Any similar structure and similar changes of the present invention should be included in the protection scope of the present invention. The use of directions such as up, down, front, back, left, and right in the present invention is only for the convenience of clear description and is not a limitation on the technical solution of the present invention.

[0017] like Figure 1-Figure 5As shown, a permanent magnet motor rotor core structure of the utility model comprises an iron core 1, wherein the iron core 1 is composed of at least two first silicon steel sheets 2 and at least two second silicon steel sheets 3 stacked in an axial direction, wherein any one of the first silicon steel sheets 2 and the second silicon steel sheets 3 is respectively provided with a plurality of magnetic steel slots 4 evenly distributed in a circumferential direction, wherein the magnetic steel slots 4 of a plurality of first silicon steel sheets 2 and second silicon steel sheets 3 are stacked to form a slot 5, wherein at least one groove 6 is provided on the side surface of any one of the magnetic steel slots 4, and the bottom surface of the groove 6 of any one of the first silicon steel sheets 2 is connected to the bottom surface of the groove 6 of any one of the first silicon steel sheets 2. A spring sheet 7 is connected, and the outer end of the spring sheet 7 extends to the outside of the groove 6; the depth direction of the groove 6 and the length direction of the magnetic steel groove 4 are both perpendicular to the axial direction of the iron core 1, the height direction of the spring sheet 7 is parallel to the depth direction of the groove 6, and the width direction of the spring sheet 7 is parallel to the length direction of the magnetic steel groove 4. The height of the spring sheet 7 is greater than the depth of the groove 6, and the difference between the height of the spring sheet 7 and the depth of the groove 6 (the height dimension of the spring sheet 7 protruding from the groove 6) is 0.1-0.3mm, and the width of the spring sheet 7 is more than twice the thickness of the first silicon steel sheet 2.

[0018] Furthermore, the groove 6 is arranged on the side of the magnetic steel slot 4 close to the core axis.

[0019] Specifically, the magnetic steel slot 4 has two longer side surfaces, which are respectively located in a plane, and the side surface on the plane that is shorter than the axis of the core 1 is defined as the side surface of the magnetic steel slot 4 close to the axis of the core 1 .

[0020] Furthermore, the distance between the spring piece 7 and the end face of the core 1 is greater than or equal to 4 mm, the depth direction of the slot 5 is parallel to the axial direction of the core 1 , and the multiple spring pieces 7 in the slot 5 are evenly distributed in the depth direction of the slot 5 .

[0021] Furthermore, a magnet is disposed in any slot 5 , and any magnet is in contact with at least two spring sheets 7 .

[0022] Furthermore, the width of the spring piece 7 is greater than or equal to 0.6 mm.

[0023] Furthermore, both sides of the inner end of the spring piece 7 are provided with rounded corners 8, and the radius of the rounded corners 8 is greater than 0.3 mm.

[0024] Specifically, the silicon steel sheets, magnetic steel slots 4, slots 5, springs 7, etc. in this embodiment all adopt well-known solutions in the prior art, which are well understood by those skilled in the art and will not be described in detail here.

[0025] The working principle of this embodiment:

[0026] When assembling the magnets, multiple magnets are inserted into the slots 5 respectively. The magnets press the springs 7. The springs 7 elastically deform to apply positive pressure to the magnets, fixing the magnets in the slots 5. The grooves 6 can ensure that there is space for the springs 7 to deform to avoid excessive interference.

[0027] The selection of the size of the positive pressure applied by the spring clip 7 needs to be converted according to the volume weight of the magnetic steel. If the magnetic steel weighs 10g, the size of the positive pressure applied by the spring clip 7 to the magnetic steel should be greater than 49N. The various dimensions of the spring clip 7 are obtained by considering the creep and yield forms of the steel plate, the processability of the stamping, and the changes in rotor performance brought about by the related structures of the spring clip 7. The height dimension of the spring clip 7 protruding from the groove 6 needs to be adjusted within the size range of 0.1-0.3mm according to the mass of the magnetic steel. The distance between the surface of the spring clip 7 and the end face of the core 1 is not less than 4mm. Each magnetic steel contacts at least two spring clips 7, and multiple spring clips 7 are evenly distributed in the depth direction of the slot 5. For example, when the number of spring clips 7 is two, they are respectively at 1 / 3 and 2 / 3 of the height of the magnetic steel (depth of the slot 5).

[0028] The utility model sets a groove 6 and a spring piece 7 in the magnetic steel slot 4, and designs the size and distribution of the spring piece 7 and the groove 6, so that when the magnetic steel is assembled into the slot 5, the spring piece 7 can firmly fix the magnetic steel in the slot 5, making it difficult for the magnetic steel to shift, reducing the risk of the magnetic steel loosening, and improving the life of the motor stator without damaging the magnetic steel. In this way, the use of traditional fillers can be eliminated, simplifying the production process, reducing material costs, and thus reducing the manufacturing cost of the entire motor. The raised spring piece applies a certain positive pressure to the magnetic steel, so that when the motor is working at high speed, the magnetic steel fixing structure provided by the utility model is still stable and reliable, with high safety, meeting the use requirements of the new energy vehicle industry.

Claims

1. A permanent magnet motor rotor core structure, characterized in that: The invention comprises an iron core, wherein the iron core is composed of at least two first silicon steel sheets and at least two second silicon steel sheets stacked in an axial direction, a plurality of magnetic steel slots are evenly distributed in any one of the first silicon steel sheets and the second silicon steel sheets along the circumferential direction, and the magnetic steel slots of the plurality of first silicon steel sheets and the second silicon steel sheets are stacked to form a slot, and at least one groove is arranged on the side surface of one side of any one of the magnetic steel slots, and a spring is connected to the bottom surface of the groove of any one of the first silicon steel sheets, and the outer end of the spring extends to the outside of the groove; the depth direction of the groove and the length direction of the magnetic steel groove are perpendicular to the axial direction of the iron core, the height direction of the spring is parallel to the depth direction of the groove, the width direction of the spring is parallel to the length direction of the magnetic steel groove, the height of the spring is greater than the depth of the groove, the difference between the height of the spring and the depth of the groove is 0.1-0.3mm, and the width of the spring is more than twice the thickness of the first silicon steel sheet.

2. A permanent magnet motor rotor core structure according to claim 1, characterized in that: The groove is arranged on one side close to the axis of the iron core.

3. The permanent magnet motor rotor core structure according to claim 1, characterized in that: The distance between the spring piece and the end face of the core is greater than or equal to 4 mm, the depth direction of the slot is parallel to the axial direction of the core, and the multiple spring pieces in the slot are evenly distributed in the depth direction of the slot.

4. The permanent magnet motor rotor core structure according to claim 1, characterized in that: A magnetic steel is arranged in any one of the slots (5), and any one of the magnetic steels is in contact with at least two spring sheets (7).

5. The permanent magnet motor rotor core structure according to claim 1, characterized in that: The width of the spring piece is greater than or equal to 0.6 mm.

6. The permanent magnet motor rotor core structure according to claim 1, characterized in that: Both sides of the inner end of the spring piece are provided with rounded corners, and the radius of the rounded corners is greater than 0.3mm.

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