Rotor assembly and motor with same

Abstract

The utility model provides a rotor assembly and a motor with the rotor assembly, rotor assembly magnetic steel and a rotor iron core. The rotor assembly also comprises an axial limiting part and a radial limiting part. The rotor core is provided with a mounting hole, the magnetic steel is mounted in the mounting hole, and the width of the mounting hole is greater than the thickness of the magnetic steel in the radial direction of the rotor core; the axial limiting part is arranged on the rotor iron core, and the axial limiting part protrudes out of the mounting hole in the radial direction of the mounting hole; the radial limiting part is arranged on the rotor iron core, the radial limiting part has a deformation state, one end of the magnetic steel abuts against the axial limiting part when the magnetic steel is installed in the installation hole, and the radial limiting part abuts against the side wall of the magnetic steel and is in the deformation state. According to the utility model, the axial limiting part and the radial limiting part are arranged, so that the magnetic steel is fixed in the axial direction and the radial direction, the production cost of the rotor core is reduced, and the process steps are reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of motors, and in particular relates to a rotor assembly and a motor with the rotor assembly. Background Art

[0002] The structure of the motor mainly includes the stator, rotor, shaft, housing, and front and rear end covers. The rotor is composed of silicon steel sheets and magnetic steel. At present, most motors use baffles to cooperate with the rotor to ensure the stacking coefficient of the rotor and limit the axial displacement of the magnetic steel and the silicon steel sheet. The rotor core is not a whole, but is formed by stacking several silicon steel sheets. Since the magnetic steel and the core need to move relative to each other, the traditional way of fixing the magnetic steel and the core is generally to fix them with magnetic steel glue. Before the magnetic steel is assembled into the core, it is first coated with magnetic steel glue, and then placed in the core, so that the magnetic steel and the core stick together and do not move relative to each other. This method is highly flexible and suitable for small batch orders or prototype production, but because the solidified magnetic steel glue will lead to poor surface cleanliness of the core, an additional glue cleaning process is required, and the cost of magnetic steel glue is relatively high, so it is rarely used in mass production processes.

[0003] Another traditional fixing method is injection molding. Compared with magnetic steel glue fixing through thermosetting, the injection molding process shows obvious advantages in cost and cleanliness. However, thermoplastics may have poor material fluidity, resulting in some positions being unable to be filled, resulting in poor dynamic balance and difficulty in adjustment. The cost of thermoplastic materials is lower than that of magnetic steel glue, but the amount used is higher than it. The cost of the entire machine with the rotor core fixed by injection molding is not low. It can be seen that both the magnetic steel glue fixing and injection molding fixing methods have the problem of complex process. Utility Model Content

[0004] The utility model provides a rotor assembly and a motor with the rotor assembly, which can solve the technical problem of complicated existing magnetic steel glue fixing and injection molding fixing processes.

[0005] The utility model provides a rotor assembly.

[0006] It includes: magnetic steel and a rotor core, and also includes an axial limiting portion and a radial limiting portion;

[0007] The rotor core has a mounting hole, the magnetic steel is mounted in the mounting hole, and in the radial direction of the rotor core, the width of the mounting hole is greater than the thickness of the magnetic steel;

[0008] The axial limiting portion is arranged on the rotor core, and in the radial direction of the mounting hole, the axial limiting portion protrudes from the mounting hole;

[0009] The radial limiting portion is arranged on the rotor core, and the radial limiting portion has a deformation state. When the magnetic steel is installed in the mounting hole, one end of the magnetic steel abuts against the axial limiting portion, and the radial limiting portion abuts against the side wall of the magnetic steel and is in the deformation state.

[0010] In some embodiments, the radial limiting portion is an elastic sheet, the mounting end of the radial limiting portion is connected to the radial inner wall of the rotor core, the free end of the radial limiting portion extends into the mounting hole, and the free end of the radial limiting portion abuts against the side wall of the magnetic steel.

[0011] In some embodiments, the axial limiting portion and the radial limiting portion are arranged relative to each other, the axial limiting portion is arranged on the radial outer wall of the rotor core, the mounting end of the radial limiting portion is connected to the radial inner wall of the rotor core, and the radial limiting portion is used to push the magnetic steel to move toward the radial outer wall of the rotor core.

[0012] In some embodiments, a radial inner wall of the rotor core is provided with an avoidance groove, the opening length of the avoidance groove in the magnetic steel installation direction is greater than the length of the radial limiting portion, and part or all of the radial limiting portion can be retracted into the avoidance groove.

[0013] In some embodiments, the rotor core comprises a first end silicon steel sheet, a middle silicon steel sheet and a second end silicon steel sheet, all of which are provided with the mounting hole, the radial outer wall of the first end silicon steel sheet is provided with the axial limiting portion, and the mounting end of the radial limiting portion is connected to the radial inner wall of the first end silicon steel sheet;

[0014] The magnetic steel is installed in the middle silicon steel sheet, and the radial inner wall of the middle silicon steel sheet is provided with the avoidance groove; one end of the magnetic steel abuts against the axial limiting portion, and the other end of the magnetic steel is connected to the second end silicon steel sheet.

[0015] In some embodiments, the rotor core includes a first end silicon steel sheet, a middle silicon steel sheet, and a second end silicon steel sheet, all of which are provided with the mounting holes, the first end silicon steel sheet has the first end, the second end silicon steel sheet has the second end, and the mounting end of the radial limiting portion is connected to the first end silicon steel sheet; the magnetic steel is installed in the middle silicon steel sheet, and the radial inner wall of the middle silicon steel sheet is provided with the avoidance groove.

[0016] In some embodiments, the middle silicon steel sheet includes at least one first silicon steel sheet, the radial outer wall of the first silicon steel sheet is provided with the axial limiting portion, and the axial limiting portion of the first silicon steel sheet has the same protruding length as the axial limiting portion of the first end silicon steel sheet;

[0017] The avoidance groove includes a first groove body, which is opened on the radial inner wall of the first silicon steel sheet, and the first groove body is arranged opposite to the axial limiting portion of the first silicon steel sheet.

[0018] In some embodiments, the middle silicon steel sheet includes at least one second silicon steel sheet, at least one first silicon steel sheet and at least one second silicon steel sheet are stacked in sequence in the installation direction of the magnetic steel, and the avoidance groove includes a second groove body, and the second groove body is opened on the radial inner wall of the second silicon steel sheet.

[0019] In some embodiments, the middle silicon steel sheet includes at least one third silicon steel sheet, at least one first silicon steel sheet, at least one second silicon steel sheet and at least one third silicon steel sheet are stacked sequentially in the installation direction of the magnetic steel, and the width from the radial inner wall to the radial outer wall of the third silicon steel sheet is smaller than the width from the second groove body to the radial outer wall of the second silicon steel sheet.

[0020] In some embodiments, the silicon steel sheet at the second end is a plate structure, or the axial limiting portion is provided on the second end.

[0021] A motor comprises a rotor assembly, wherein the rotor assembly is the above-mentioned rotor assembly.

[0022] The utility model provides a rotor assembly and a motor having the rotor assembly, which have the following beneficial effects:

[0023] (1) After the magnetic steel is installed in the rotor core, the magnetic steel is fixed in the axial direction by the axial limiting part, and the magnetic steel is fixed in the radial direction by the radial limiting part, so that the magnetic steel is fixed in both the axial and radial directions. After the magnetic steel of this embodiment is installed in place, the magnetic steel can be limited, and there is no need to use glue to bond the magnetic steel and the rotor core, nor is there a complex process of mold opening and thermoplastic fixing. Moreover, after adopting this method, there is no need to install a baffle structure in the axial direction of the rotor core, which reduces the production cost of the rotor core and reduces the process steps. After the baffle structure is eliminated, the axial length of the rotor assembly is also reduced, so that the motor space is reduced and becomes more compact.

[0024] (2) Since there is a mutual repulsion phenomenon between the magnets, which causes the magnets to pop out of the installation hole, the present embodiment provides an axial limiting portion and a radial limiting portion. When one magnet is installed, the magnet is limited. Even if another magnet is installed, the installed magnet will not pop out of the magnet slot. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the implementation of the utility model or the technical solution in the prior art, the following is a brief introduction to the drawings required for the implementation or the prior art description. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0026] Figure 1 It is a schematic diagram of the magnetic steel in the first position according to the embodiment of the utility model;

[0027] Figure 2 This is a schematic diagram of the radial limiting portion of the embodiment of the utility model when it is retracted;

[0028] Figure 3 It is a schematic diagram of the magnetic steel in the second position according to the embodiment of the utility model;

[0029] Figure 4 It is a schematic diagram of a rotor core of an embodiment of the utility model including a first end silicon steel sheet and a middle silicon steel sheet;

[0030] Figure 5 A schematic diagram of a silicon steel sheet at a first end portion of an embodiment of the utility model;

[0031] Figure 6 A schematic diagram of a first silicon steel sheet according to an embodiment of the present utility model;

[0032] Figure 7 A schematic diagram of a second silicon steel sheet according to an embodiment of the present utility model;

[0033] Figure 8 This is a schematic diagram of a third silicon steel sheet according to an embodiment of the present utility model.

[0034] Figures: 1-magnetic steel; 2-rotor core; 201-mounting hole; 21-first end silicon steel sheet; 22-middle silicon steel sheet; 221-first silicon steel sheet; 222-second silicon steel sheet; 223-third silicon steel sheet; 24-avoidance groove; 241-first slot body; 242-second slot body; 3-axial limiting portion; 4-radial limiting portion. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means a limitation on the utility model and its application or use. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0036] In the description of the present utility model, it needs to be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present utility model and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, and therefore cannot be understood as limiting the scope of protection of the present utility model; the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0037] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0038] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the utility model.

[0039] See also Figures 1 to 4As shown, according to an embodiment of the utility model, a rotor assembly is provided, comprising a magnetic steel 1 and a rotor core 2, and also comprising an axial limiting portion 3 and a radial limiting portion 4; the rotor core 2 has a mounting hole 201, the magnetic steel 1 is mounted in the mounting hole 201, and in the radial direction of the rotor core 2, the width of the mounting hole 201 is greater than the thickness of the magnetic steel 1; the axial limiting portion 3 is arranged on the rotor core 2, and in the radial direction of the mounting hole 201, the axial limiting portion 3 protrudes from the mounting hole 201; the radial limiting portion 4 is arranged on the rotor core 2, and the radial limiting portion 4 has a deformation state, and when the magnetic steel 1 is installed in the mounting hole 201, one end of the magnetic steel 1 abuts against the axial limiting portion 3, and the radial limiting portion 4 abuts against the side wall of the magnetic steel 1 and is in a deformation state.

[0040] Specifically, the magnetic steel 1 of this embodiment is installed in the rotor core. The magnetic steel 1 is installed in the rotor core in a sliding manner. After the magnetic steel 1 is installed in the rotor core 2, the position of the magnetic steel 1 does not change. The magnetic steel 1 of this embodiment has a first position and a second position. The first position is the initial position and the second position is the final position. The installation direction of the magnetic steel 1 is from top to bottom (with Figure 3 The upper and lower positions shown in the figure are taken as the reference). When the magnetic steel 1 is in the first position, the bottom of the magnetic steel 1 is placed on the first end of the rotor core 2, one side wall of the magnetic steel 1 contacts the axial limit part 3, and the other side wall of the magnetic steel 1 contacts the radial limit part 4. The radial limit part 4 is arranged to extend, and the radial limit part 4 will not be deformed when not subjected to force. The magnetic steel 1 slides downward, and the radial limit part 4 contacts the side wall of the magnetic steel 1. The radial limit part 4 is deformed by the extrusion force applied by the magnetic steel 1. When the side wall of the magnetic steel 1 is no longer in contact with the side wall of the axial limit part 3, the deformation degree of the radial limit part 4 will be weakened and the magnetic steel 1 will be pushed to move toward the radial outer wall of the rotor core 2. At this time, the top of the magnetic steel 1 is in contact with the axial limit part 3, and the axial direction of the magnetic steel 1 is fixed. The magnetic steel 1 is in the second position, and the magnetic steel 1 has been installed in place and does not need to be moved.

[0041] It is worth noting that the radial inner wall and the radial outer wall of the rotor core 2 in this embodiment refer to the inner and outer walls of the rotor core 2 in the radial direction at the mounting hole 201 after the mounting hole 201 is opened.

[0042] In this embodiment, after the magnetic steel 1 is installed in the rotor core 2, the magnetic steel 1 is affected by the axial limiting portion 3 in the axial direction, and the magnetic steel 1 is fixed in the axial direction. The magnetic steel 1 is affected by the radial limiting portion 4 in the radial direction, and the magnetic steel 1 is fixed in the radial direction, so that the magnetic steel 1 is fixed in both the axial and radial directions. After the magnetic steel 1 of this embodiment is installed in place, the magnetic steel 1 can be limited, and the fixing method is reliable. There is no need to use glue to bond and fix the magnetic steel 1 and the rotor core 2, and there is no need for a complex process of mold opening and thermoplastic fixing. Moreover, after adopting this method, there is no need to install a baffle structure in the axial direction of the rotor core 2, which reduces the production cost of the rotor core 2 and reduces the process steps. After the baffle structure is cancelled, the axial length of the rotor assembly is also reduced, so that the motor space is reduced and becomes more compact. In addition, due to the mutual repulsion between the magnets 1 and 1, which causes the magnet 1 to pop out of the mounting hole 201, an axial limiting portion 3 and a radial limiting portion 4 are provided in this embodiment. When one magnet 1 is installed, the magnet 1 is limited. Even if another magnet 1 is installed, the installed magnet 1 will not pop out of the magnet 1 groove.

[0043] See also Figure 4 As shown, the radial limiting portion 4 of the rotor assembly is an elastic sheet, the mounting end of the radial limiting portion 4 is connected to the radial inner wall of the rotor core 2, the free end of the radial limiting portion 4 extends into the mounting hole 201, and the free end of the radial limiting portion 4 abuts against the side wall of the magnetic steel 1.

[0044] Specifically, when the radial limiting portion 4 is an elastic sheet, the side of the elastic sheet in contact with the magnetic steel 1 is a free end, and the magnetic steel 1 will abut against different positions of the radial limiting portion 4 during the downward sliding process. The magnetic steel 1 is in the first position, one side wall of the magnetic steel 1 is in contact with the axial limiting portion 3, and the other side wall of the magnetic steel 1 is in contact with the free end of the radial limiting portion 4. At this time, the angle between the radial limiting portion 4 and the radial inner wall of the rotor core 2 is large, and the radial limiting portion 4 is in an extended state. The magnetic steel 1 continues to slide downward, and the angle between the radial limiting portion 4 and the radial inner wall of the rotor core 2 gradually decreases. The radial limiting portion 4 is deformed by the extrusion force applied by the magnetic steel 1 until the side wall of the magnetic steel 1 is no longer in contact with the axial limiting portion 3, and the elasticity of the radial limiting portion 4 is restored to a certain extent, thereby pushing the magnetic steel 1 to move outward, the magnetic steel 1 is in contact with the radial outer wall of the rotor core 2, the top of the magnetic steel 1 abuts against the axial limiting portion 3, and the bottom of the magnetic steel 1 is connected to the second end of the rotor core 2.

[0045] In this embodiment, the magnetic steel 1 needs to slide from the first position to the second position. Since the axial limiting portion 3 is protruding from the mounting hole 201, when the side wall of the magnetic steel 1 is no longer in contact with the axial limiting portion 3, the radial limiting portion 4 can push the magnetic steel 1. In this embodiment, the axial limiting portion 3 and the radial limiting portion 4 are provided, and the elastic force of the radial limiting member can be fully utilized to limit the position of the magnetic steel 1 in the radial direction. Moreover, when the rotor core 2 is running, the rotation generates centrifugal force. Under the action of the centrifugal force, the magnetic steel 1 can be tightly attached to the radial outer wall of the rotor core 2, ensuring that the magnetic steel 1 can still be firmly fixed and limited during the operation of the motor.

[0046] In another embodiment, the radial limiting portion 4 can not only be set as an elastic sheet, but also can be a spring or elastic rubber, or a bow-shaped sheet. When the radial limiting portion 4 is a spring, the spring can be set horizontally, and multiple springs can be set on the radial inner wall of the rotor core 2. One end of the spring is connected to the radial inner wall of the rotor core 2, and the other end of the spring is in contact with the magnet 1; the spring can be set obliquely, and only one spring is set.

[0047] See also Figures 1 to 3 As shown, a radial inner wall of the rotor core 2 is provided with an avoidance groove 24 , the opening length of the avoidance groove 24 in the installation direction of the magnetic steel 1 is greater than the length of the radial limiting portion 4 , and part or all of the radial limiting portion 4 can be retracted into the avoidance groove 24 .

[0048] Specifically, during the downward sliding of the magnet 1, the magnet 1 squeezes the radial limiting portion 4, and the radial limiting portion 4 is gradually retracted, that is, the angle between the radial limiting portion 4 and the radial inner wall of the rotor core 2 will gradually decrease, and the portion of the radial limiting portion 4 retracted into the avoidance groove 24 will also gradually increase.

[0049] In this embodiment, the radial limiting portion 4 has a certain thickness, and the avoidance groove 24 is provided to provide a certain space for the retraction of the radial limiting portion 4. The conventional mounting hole 201 of the rotor core 2 has enough space to push the magnet 1 to the predetermined position, thereby preventing the radial limiting portion 4 from interfering with the sliding of the magnet 1. After the installation of the magnet 1 is completed, the radial limiting portion 4 is reset under the action of the elastic force, pushing the magnet 1 toward the radial outer wall of the rotor core 2, and being limited and fixed by the axial limiting portion 3.

[0050] See also Figure 5 As shown, the axial limiting portion 3 and the radial limiting portion 4 are arranged opposite to each other, the axial limiting portion 3 is arranged on the radial outer wall of the rotor core 2, the mounting end of the radial limiting portion 4 is connected to the radial inner wall of the rotor core 2, and the radial limiting portion 4 is used to push the magnetic steel 1 to move toward the radial outer wall of the rotor core 2.

[0051] In this embodiment, the axial limiting portion 3 is to limit the magnetic steel 1 in the axial direction, and the radial limiting portion 4 is to limit the magnetic steel 1 in the radial direction. The axial limiting portion 3 and the radial limiting portion 4 are arranged relative to each other, and can better abut the magnetic steel 1 in two directions during the sliding process of the magnetic steel 1, and the force on both sides of the magnetic steel 1 is more uniform. In this embodiment, it is preferred that the axial limiting portion 3 is arranged on the radial outer wall of the rotor core 2, and the mounting end of the radial limiting portion 4 is connected to the radial inner wall of the rotor core 2. During the rotation of the rotor assembly, the magnetic steel 1 will be subjected to centrifugal force, and the magnetic steel 1 will tend to move away from the axis. The axial limiting portion 3 and the radial limiting portion 4 are respectively located on the radial outer and inner sides of the rotor core 2. Under the action of centrifugal force, the magnetic steel 1 will not squeeze the radial limiting portion 4, but the radial limiting portion 4 can abut against the side wall of the magnetic steel 1. In other embodiments, the axial limiting portion 3 and the radial limiting portion 4 may not be arranged relative to each other, as long as they can abut against the side wall of the magnetic steel 1.

[0052] See also Figure 4 and Figure 5 As shown, the rotor core 2 includes a first end silicon steel sheet 21, a middle silicon steel sheet 22 and a second end silicon steel sheet, all of which are provided with mounting holes 201. The first end silicon steel sheet 21, the middle silicon steel sheet 22 and the second end silicon steel sheet are stacked in sequence from top to bottom, and the radial outer wall of the first end silicon steel sheet 21 is provided with an axial limiting portion 3, and the mounting end of the radial limiting portion 4 is connected to the radial inner wall of the first end silicon steel sheet 21; the magnetic steel 1 is installed in the middle silicon steel sheet 22, and the radial inner wall of the middle silicon steel sheet 22 is provided with an avoidance groove 24; one end of the magnetic steel 1 is abutted against the axial limiting portion 3, and the other end of the magnetic steel 1 is connected to the second end silicon steel sheet.

[0053] Specifically, the rotor core 2 is formed by laminating silicon steel sheets, the first end silicon steel sheet 21 has a first end, the axial stopper is connected to the radial outer wall of the first end silicon steel sheet 21, the axial stopper 3 protrudes from the mounting hole 201 of the first end silicon steel sheet 21, the mounting end of the radial stopper 4 is connected to the radial inner wall of the first end silicon steel sheet 21, and the free end of the radial stopper 4 sequentially extends into the mounting holes 201 of the first end silicon steel sheet 21 and the middle silicon steel sheet 22. When the magnetic steel 1 is in the first position, the bottom of the magnetic steel 1 contacts the side wall of the axial stopper 3 on the first end silicon steel sheet 21, the magnetic steel 1 gradually slides downward, and the magnetic steel 1 squeezes the radial stopper 4. When the magnetic steel 1 is installed in the middle silicon steel sheet 22, the top of the magnetic steel 1 abuts against the axial stopper 3 of the first end silicon steel sheet 21, the bottom of the magnetic steel 1 is connected to the second end silicon steel sheet, and the side wall of the magnetic steel 1 contacts the radial outer wall of the middle silicon steel sheet 22.

[0054] In this embodiment, an axial limit portion 3 and a radial limit portion 4 are to be set on the rotor core 2. Combined with the method of stacking silicon steel sheets in the rotor core 2, at least three types of silicon steel sheets can be set according to the setting positions of the axial limit portion 3, the radial limit portion 4 and the avoidance groove 24, which can meet the setting position requirements of the axial limit portion 3, the radial limit portion 4 and the avoidance groove 24 in this embodiment and can be flexibly adjusted.

[0055] See also Figure 6 As shown, the middle silicon steel sheet 22 includes at least one first silicon steel sheet 221, and the radial outer wall of the first silicon steel sheet 221 is provided with an axial limit portion 3, and the axial limit portion 3 of the first silicon steel sheet 221 is the same as the protruding length of the axial limit portion 3 of the first end silicon steel sheet 21; the avoidance groove 24 includes a first groove body 241, and the first groove body 241 is opened on the radial inner wall of the first silicon steel sheet 221, and the first groove body 241 is arranged opposite to the axial limit portion 3 of the first silicon steel sheet 221.

[0056] In this embodiment, the first silicon steel sheet 221 is provided with an axial limit portion 3. When the top end of the magnetic steel 1 slides to this position, the side wall of the magnetic steel 1 is still in contact with the axial limit portion 3. When the magnetic steel 1 is in the second position, the magnetic steel 1 no longer moves, and the top end of the magnetic steel 1 abuts against the axial limit portion 3 of the first silicon steel sheet 221. The first slot 241 provides space for the retracted radial limit portion 4. Providing the axial limit portion 3 on the first silicon steel sheet 221 can increase the force of the axial limit portion 3 on the magnetic steel 1 in the axial direction, and avoid the problem that the axial limit portion 3 is only provided on the first end silicon steel sheet 21, and the axial limit portion 3 has low rigidity and cannot limit the magnetic steel 1.

[0057] In this embodiment, the first silicon steel sheet 221 is preferably provided with an axial limit portion 3. In other embodiments, the first silicon steel sheet 221 may not be provided with the axial limit portion 3, and only be provided with the first groove body 241. If the rotor assembly is to be used in a large motor, the thickness of the first end silicon steel sheet 21 can be increased, and the corresponding thickness of the axial limit portion 3 is also increased, thereby ensuring that when the first silicon steel sheet 221 is not provided with the axial limit portion 3, the axial limit portion 3 on the first end silicon steel sheet 21 can still limit the axial position of the magnetic steel 1.

[0058] See also Figure 7 As shown, the middle silicon steel sheet 22 includes at least one second silicon steel sheet 222, at least one first silicon steel sheet 221 and at least one second silicon steel sheet 222 are stacked in sequence in the installation direction of the magnetic steel 1, and the avoidance groove 24 includes a second groove body 242, and the second groove body 242 is opened on the radial inner wall of the second silicon steel sheet 222.

[0059] In this embodiment, after the side wall of the magnetic steel 1 is not in contact with the axial limiting portion 3, in order for the axial limiting portion 3 to be able to axially limit the magnetic steel 1, the bottom end of the magnetic steel 1 needs to abut against the bottom end of the axial limiting portion 3. Therefore, the second silicon steel sheet 222 is only provided with the avoidance groove 24, but not the axial limiting portion 3, so that the radial limiting portion 4 extends out under the action of the elastic force, and the radial limiting portion 4 pushes the magnetic steel 1 to move toward the radial outer wall of the middle silicon steel sheet 22. Not providing the axial limiting portion 3 on the second silicon steel sheet 222 can provide a certain space for the magnetic steel 1, so that the magnetic steel 1 abuts against the axial limiting portion 3, and the second groove body 242 provides a certain space for the retraction of the radial limiting portion 4.

[0060] See also Figure 8 As shown, the middle silicon steel sheet 22 includes at least one third silicon steel sheet 223, at least one first silicon steel sheet 221, at least one second silicon steel sheet 222 and at least one third silicon steel sheet 223 are stacked in sequence in the installation direction of the magnetic steel 1, and the width from the radial inner wall to the radial outer wall of the third silicon steel sheet 223 is smaller than the width from the second groove body 242 of the second silicon steel sheet 222 to the radial outer wall.

[0061] In this embodiment, when the magnetic steel 1 slides to the third silicon steel sheet 223, the top end of the magnetic steel 1 has abutted against the axial limiting portion 3, and the radial limiting portion 4 has also pushed the magnetic steel 1 to contact the radial outer wall of the middle silicon steel sheet 22, and there is no need to set a groove body. Therefore, only a conventional mounting hole 201 is set on the third silicon steel sheet 223, and the axial limiting portion 3 and the groove body are not set.

[0062] The silicon steel sheet at the second end is a plate structure, or an axial limiting portion 3 is provided on the second end.

[0063] Specifically, when the magnetic steel 1 slides to the second position, the bottom end of the magnetic steel 1 is connected to the second end silicon steel sheet, and the end limit portion can axially limit the magnetic steel 1. Both ends of the magnetic steel 1 are limited, and the magnetic steel 1 does not move. When the second end silicon steel sheet is a plate structure, the second end silicon steel sheet does not have a mounting hole 201, and the axial limit portion 3 and the radial limit portion 4 are not provided, and the bottom end of the magnetic steel 1 abuts against the second end silicon steel sheet; when the second end silicon steel sheet is also provided with an axial limit portion 3, the first end silicon steel sheet 21 and the axial limit portion 3 on the second end silicon steel sheet jointly limit the axial position of the magnetic steel 1, and the bottom end of the magnetic steel 1 abuts against the axial limit portion 3. In this embodiment, since the magnetic steel 1 is to be loaded from the first end silicon steel sheet 21, and the second end silicon steel sheet needs to ensure that the bottom end of the magnetic steel 1 can be limited, the structure of the second end silicon steel sheet can be flexibly selected according to the installation requirements.

[0064] A motor comprises a rotor assembly, wherein the rotor assembly is the above-mentioned rotor assembly.

[0065] After the rotor assembly is applied in the motor, the magnetic steel 1 is installed in the rotor core 2, and the magnetic steel 1 is fixed in the axial direction by the axial limiting portion 3, and the magnetic steel 1 is fixed in the axial direction by the radial limiting portion 4 in the radial direction, so that the magnetic steel 1 is fixed in the radial direction. After the magnetic steel 1 of this embodiment is installed in place, the magnetic steel 1 can be limited, and the fixing method is reliable. It is not necessary to use glue to bond the magnetic steel 1 and the rotor core 2, and it is not necessary to use a complex process of mold opening and thermoplastic fixing. Moreover, after adopting this method, it is no longer necessary to install a baffle structure in the axial direction of the rotor core 2, which reduces the production cost of the rotor core 2 and reduces the process steps. After the baffle structure is cancelled, the axial length of the rotor assembly is also reduced, so that the motor space is reduced and becomes more compact. In addition, due to the mutual repulsion between the magnets 1 and 1, which causes the magnet 1 to pop out of the mounting hole 201, an axial limiting portion 3 and a radial limiting portion 4 are provided in this embodiment. When one magnet 1 is installed, the magnet 1 is limited. Even if another magnet 1 is installed, the installed magnet 1 will not pop out of the magnet 1 groove.

[0066] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0067] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention. The above are only preferred implementations of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present invention, and these improvements and variations should also be regarded as the protection scope of the present invention.

Claims

1. A rotor assembly, comprising: The magnetic steel (1) and the rotor core (2) are characterized by further comprising an axial limiting portion (3) and a radial limiting portion (4); The rotor core (2) has a mounting hole (201), the magnetic steel (1) is mounted in the mounting hole (201), and in the radial direction of the rotor core (2), the width of the mounting hole (201) is greater than the thickness of the magnetic steel (1); The axial limiting portion (3) is arranged on the rotor core (2), and in the radial direction of the mounting hole (201), the axial limiting portion (3) protrudes from the mounting hole (201); The radial limiting portion (4) is arranged on the rotor core (2), and the radial limiting portion (4) has a deformed state. When the magnetic steel (1) is installed in the mounting hole (201), one end of the magnetic steel (1) abuts against the axial limiting portion (3), and the radial limiting portion (4) abuts against the side wall of the magnetic steel (1) and is in the deformed state.

2. The rotor assembly according to claim 1, characterized in that The radial limiting portion (4) is an elastic sheet, the mounting end of the radial limiting portion (4) is connected to the rotor core (2), the free end of the radial limiting portion (4) extends into the mounting hole (201), and the free end of the radial limiting portion (4) abuts against the side wall of the magnetic steel (1).

3. The rotor assembly according to claim 2, characterized in that: The axial limiting portion (3) and the radial limiting portion (4) are arranged opposite to each other. The axial limiting portion (3) is arranged on the radial outer wall of the rotor core (2). The mounting end of the radial limiting portion (4) is connected to the radial inner wall of the rotor core (2). The radial limiting portion (4) is used to push the magnetic steel (1) to move toward the radial outer wall of the rotor core (2).

4. The rotor assembly according to claim 3, characterized in that: The radial inner wall of the rotor core (2) is provided with an avoidance groove (24), the opening length of the avoidance groove (24) in the installation direction of the magnetic steel (1) is greater than the length of the radial limiting portion (4), and part or all of the radial limiting portion (4) can be retracted into the avoidance groove (24).

5. The rotor assembly according to claim 4, characterized in that: The rotor core (2) comprises a second end silicon steel sheet and a first end silicon steel sheet (21) and a middle silicon steel sheet (22) both of which are provided with the mounting hole (201); the radial outer wall of the first end silicon steel sheet (21) is provided with the axial limiting portion (3); and the mounting end of the radial limiting portion (4) is connected to the radial inner wall of the first end silicon steel sheet (21); The magnetic steel (1) is installed in the middle silicon steel sheet (22), and the radial inner wall of the middle silicon steel sheet (22) is provided with the avoidance groove (24); one end of the magnetic steel (1) is in contact with the axial limiting portion (3), and the other end of the magnetic steel (1) is connected to the second end silicon steel sheet.

6. The rotor assembly according to claim 5, characterized in that The middle silicon steel sheet (22) comprises at least one first silicon steel sheet (221), the radial outer wall of the first silicon steel sheet (221) is provided with the axial limiting portion (3), and the protruding length of the axial limiting portion (3) of the first silicon steel sheet (221) is the same as that of the axial limiting portion (3) of the first end silicon steel sheet (21); The avoidance groove (24) comprises a first groove body (241), the first groove body (241) is opened on the radial inner wall of the first silicon steel sheet (221), and the first groove body (241) is arranged opposite to the axial limiting portion (3) of the first silicon steel sheet (221).

7. The rotor assembly according to claim 6, characterized in that The middle silicon steel sheet (22) comprises at least one second silicon steel sheet (222), at least one of the first silicon steel sheets (221) and at least one of the second silicon steel sheets (222) are sequentially stacked in the installation direction of the magnetic steel (1), and the avoidance groove (24) comprises a second groove body (242), and the second groove body (242) is opened on the radial inner wall of the second silicon steel sheet (222).

8. The rotor assembly according to claim 7, characterized in that The middle silicon steel sheet (22) comprises at least one third silicon steel sheet (223), wherein at least one first silicon steel sheet (221), at least one second silicon steel sheet (222) and at least one third silicon steel sheet (223) are stacked in sequence in the installation direction of the magnetic steel (1), and the width from the radial inner wall to the radial outer wall of the third silicon steel sheet (223) is smaller than the width from the second slot body (242) to the radial outer wall of the second silicon steel sheet (222).

9. The rotor assembly according to claim 5, characterized in that: The second end silicon steel sheet is a plate structure, or the second end silicon steel sheet is provided with the mounting hole (201), and the radial outer wall of the second end silicon steel sheet is provided with the axial limiting portion (3).

10. An electric machine, comprising a rotor assembly, characterized in that: The rotor assembly is the rotor assembly according to any one of claims 1 to 9.

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