Rotor assembly and brushless direct current motor
By employing a three-layer ring structure and two-layer spaced damping material in the rotor assembly of a brushless DC motor, the noise problem at different speed and frequency ranges is solved, achieving a wider range of noise reduction and structural stability.
Patent Information
- Application Number
- CN202423152065.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-19
- Publication Date
- 2025-11-21
- Estimated Expiration
- 2034-12-19
AI Technical Summary
The existing vibration-damping rotor structure of brushless DC motors cannot meet the noise requirements at different speed and frequency ranges. In particular, DC motors have a wide range of operating speeds, and vibration-damping materials with single hardness cannot simultaneously optimize noise at different frequency ranges.
The rotor core adopts a three-layer ring structure, with an inner core, a middle core, and an outer core arranged alternately, and two layers of damping material filling the spaces between them. The first and second damping material layers are made of different or the same rubber materials, respectively filling the spaces between the inner core and the middle core and between the middle core and the outer core, and each protruding along the axial and radial directions of the rotor core to form an I-shaped structure.
By combining nested multi-layer damping material structures, the noise reduction frequency range is broadened, achieving noise optimization at multiple speeds and improving the damping effect and structural strength of the rotor assembly.
Smart Images
Figure CN223583912U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of brushless DC motors, and particularly relates to a rotor assembly and a brushless DC motor. BACKGROUND
[0002] A brushless DC motor usually adopts a damping rotor to optimize motor load noise. Due to structural reasons, most existing motor damping rotors are single-damping structures. Even if a double-damping structure is adopted, it is integrally arranged. The materials of all damping structures usually only have a single hardness. In actual use, different damping materials with different hardnesses have different effects on noise of the same motor at different speeds and in different frequency bands. Especially, the speed range of a DC motor is large, and a damping rotor only has one damping system and can only have one hardness, which cannot meet the noise requirements at different speed frequency bands. CONTENT OF THE UTILITY MODEL
[0003] Therefore, the application provides a rotor assembly and a brushless DC motor, which can solve the problem that a brushless DC motor in the prior art cannot meet the noise requirements at different speed frequency bands.
[0004] In order to solve the above problem, the application provides a rotor assembly, which comprises:
[0005] A rotor core is composed of at least three annular bodies: an inner layer core, a middle layer core and an outer layer core, which are sequentially and spaced apart from inside to outside.
[0006] A damping layer comprises at least a first damping material layer and a second damping material layer which are spaced apart, the first damping material layer is filled between the inner layer core and the middle layer core, and the second damping material layer is filled between the middle layer core and the outer layer core.
[0007] In some embodiments,
[0008] The first damping material layer protrudes the rotor core in the axial direction of the rotor core, and the thickness of the protruding part in the radial direction of the rotor core is greater than the gap between the inner layer core and the middle layer core. The second damping material layer protrudes the rotor core in the axial direction of the rotor core, and the thickness of the protruding part in the radial direction of the rotor core is greater than the gap between the middle layer core and the outer layer core. The protruding parts of the first damping material layer and the second damping material layer in the rotor core are spaced apart.
[0009] In some embodiments,
[0010] The inner layer core outer wall is provided with a first boss extending in the radial direction, the middle layer core inner wall is provided with a second boss extending in the radial direction, and the first boss and the second boss are staggered in the circumferential direction.
[0011] In some embodiments,
[0012] The first boss is provided with a first limiting hole extending in the axial direction, the second boss is provided with a second limiting hole extending in the axial direction, and the first damping material layer fills the first limiting hole and the second limiting hole.
[0013] In some embodiments,
[0014] The middle layer core outer wall is provided with a third boss extending in the radial direction, the outer layer core inner wall is provided with a fourth boss extending in the radial direction, and the third boss and the fourth boss are staggered in the circumferential direction.
[0015] In some embodiments,
[0016] The third boss is provided with a third limiting hole extending in the axial direction, the fourth boss is provided with a fourth limiting hole extending in the axial direction, and the second damping material layer fills the third limiting hole and the fourth limiting hole.
[0017] In some embodiments,
[0018] The outer layer core outer wall is provided with a fifth boss extending in the radial direction, the fifth boss is provided with a plurality of bosses and is uniformly distributed along the outer layer core outer wall in the circumferential direction, and the adjacent fifth bosses are attached with magnetic tiles.
[0019] In some embodiments,
[0020] The adjacent magnetic tiles are filled with an injection molding material layer, the injection molding material layer protrudes from the rotor core in the axial direction, and the protruding part is spaced apart from the part protruding from the rotor core by the second damping material layer.
[0021] In some embodiments,
[0022] The first damping material layer and the second damping material layer are made of different rubber materials.
[0023] According to another aspect of the present application, a brushless DC motor is provided, comprising a rotor assembly as described above.
[0024] The rotor assembly provided by the application comprises: a rotor core composed of at least three layers of annular bodies, i.e., an inner layer core, a middle layer core and an outer layer core, wherein the inner layer core, the middle layer core and the outer layer core are sequentially and spacedly arranged from inside to outside; and a damping layer comprising at least a first damping material layer and a second damping material layer which are spacedly arranged, the first damping material layer is filled between the inner layer core and the middle layer core, and the second damping material layer is filled between the middle layer core and the outer layer core.
[0025] The application has the following beneficial effects:
[0026] By combining the nested multi-rotor core structure and arranging two layers of separated damping material layers, a larger noise reduction range of the rotor assembly can be increased, and the beneficial effect of reducing noise at multiple frequencies can be achieved. BRIEF DESCRIPTION OF DRAWINGS
[0027] In order to more clearly illustrate the embodiments of the application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced as follows. The drawings in the following description are only exemplary, and other drawings can be derived from the provided drawings without creative labor for those skilled in the art.
[0028] Figure 1 It is an outer view of the rotor assembly of the embodiment of the application.
[0029] Figure 2 It is a front view of the rotor assembly of the embodiment of the application.
[0030] Figure 3 It is a top view of the rotor assembly of the embodiment of the application.
[0031] Figure 4 It is a view in the direction of A-A in the embodiment of the application. Figure 2
[0032] It is a view in the direction of B-B in the embodiment of the application. Figure 5 Figure 4 It is a view in the direction of C-C in the embodiment of the application.
[0033] Figure 6 Figure 2 It is a view in the direction of C-C in the embodiment of the application.
[0034] Figure 7 It is a half-section structural schematic view of the rotor assembly of the embodiment of the application.
[0035] Figure 8 It is a structural schematic view of the inner layer core of the embodiment of the application.
[0036] Figure 9 It is a structural schematic view of the middle layer core of the embodiment of the application.
[0037] Figure 10 Structure diagram of outer core of the embodiment of the present application.
[0038] The reference signs are shown as:
[0039] 1, inner core; 11, first boss; 111, first limiting hole;
[0040] 2, middle core; 21, second boss; 211, second limiting hole; 22, third boss; 221, third limiting hole;
[0041] 3, outer core; 31, fourth boss; 311, fourth limiting hole; 32, fifth boss;
[0042] 4, first damping material layer; 5, injection material layer; 6, second damping material layer; 7, magnetic tile. DETAILED DESCRIPTION
[0043] The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. The description of the at least one exemplary embodiment is actually only illustrative, but not as any limitation on the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.
[0044] In the description of the present application, it should be understood that the orientation words such as “front, back, up, down, left, right”, “transverse, vertical, perpendicular, horizontal” and “top, bottom” and the like indicate the orientation or position relationship shown in the drawings, which are only for the convenience of describing the present application and simplifying the description, and do not indicate and imply that the indicated device or element must have a specific orientation or be constructed and operated in a specific orientation, therefore it cannot be understood as a limitation on the scope of protection of the present application; the orientation words “inner, outer” refer to the inner and outer of the contour of each component itself.
[0045] For purposes of the description hereinafter, spatial relative terms, such as "above", "below", "upper", "lower", and the like, can be used to describe the relative position of one element or feature to another element or feature as illustrated in the figures. It will be understood that the spatial relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientations depicted in the figures. For example, if the device in the figures is turned over, elements described as "above" or "up" other elements or features would then be oriented "below" or "down" the other elements or features. Thus, the exemplary term "above" can encompass both an orientation of above and below. The device can be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
[0046] In addition, it should be noted that the use of "first", "second", and the like words of resemblance to limit parts, only for the convenience of the corresponding parts are distinguished, such as no other declaration, the above words have no special meaning, therefore can not be understood as limiting the scope of the application.
[0047] In conjunction with reference to Figures 1 to 10 As shown, according to the embodiment of the application, a rotor assembly, comprising:
[0048] The rotor core is composed of at least three layers of ring body: inner core 1, middle core 2 and outer core 3, and the inner core 1, the middle core 2 and the outer core 3 are arranged in sequence from inside to outside.
[0049] The damping layer at least includes a first damping material layer 4 and a second damping material layer 6 arranged at intervals, the first damping material layer 4 is filled between the inner core 1 and the middle core 2, and the second damping material layer 6 is filled between the middle core 2 and the outer core 3.
[0050] The application can increase the larger noise reduction range of the rotor assembly by combining the nested multi-rotor core structure with two layers of separated damping material layers, and realize the beneficial effect of reducing noise at multiple frequencies.
[0051] The rotor core adopts at least three layers of annular bodies, so that the inner core 1 and the middle core 2, and the middle core 2 and the outer core 3 are filled with damping materials to form a first damping material layer 4 and a second damping material layer 6. Due to the separation of the middle core 2, the first damping material layer 4 and the second damping material layer 6 are arranged in a spaced manner. The first damping material layer 4 and the second damping material layer 6 have damping effects, but based on different sizes and positions, the first damping material layer 4 and the second damping material layer 6 have different damping effects, and the damping frequencies are different. In this way, the damping frequency is widened, and the noise reduction effect is better.
[0052] The first damping material layer 4 and the second damping material layer 6 are arranged in a spaced manner, and the materials of the first damping material layer 4 and the second damping material layer 6 can be the same or different. Specifically, the first damping material layer 4 and the second damping material layer 6 can both be rubber materials, which can be rubber materials of different hardness or different materials.
[0053] The first damping material layer 4 is filled between the inner core 1 and the middle core 2 and forms an integral structure with the inner core 1 and the middle core 2, and the second damping material layer 6 is filled between the middle core 2 and the outer core 3 and forms an integral structure with the middle core 2 and the outer core 3. In this way, the inner core 1, the first damping material layer 4, the middle core 2, the second damping material layer 6, and the outer core 3 form an integrated rotor core. The center hole of the inner core 1 is a shaft hole, which matches the size of the shaft.
[0054] In some embodiments,
[0055] The first damping material layer 4 protrudes the rotor core in the axial direction of the rotor core, and the thickness of the protruding part in the radial direction of the rotor core is greater than the gap between the inner core 1 and the middle core 2. The second damping material layer 6 protrudes the rotor core in the axial direction of the rotor core, and the thickness of the protruding part in the radial direction of the rotor core is greater than the gap between the middle core 2 and the outer core 3. The protruding parts of the first damping material layer 4 and the second damping material layer 6 are arranged in a spaced manner.
[0056] The first damping material layer 4 protrudes the end of the rotor core, and the thickness of the protruding part in the radial direction of the rotor core is greater than the gap between the inner core 1 and the middle core 2, so that the first damping material layer 4 has an I-shaped structure in the axial cross section of the rotor core. Correspondingly, the second damping material layer 6 also protrudes the end of the rotor core, and the thickness of the protruding part in the radial direction of the rotor core is greater than the gap between the middle core 2 and the outer core 3, so that the second damping material layer 6 also has an I-shaped structure in the axial cross section of the rotor core. In this way, the ends of the rotor core are protected by damping, and the damping effect is improved.
[0057] The first damping material layer 4 and the second damping material layer 6 are arranged in intervals and do not interfere with each other, thereby playing different damping effects, increasing the frequency of noise reduction, and improving the noise reduction effect.
[0058] In some embodiments,
[0059] The inner layer core 1 is provided with a first boss 11 extending in the radial direction on the outer wall, the middle layer core 2 is provided with a second boss 21 extending in the radial direction on the inner wall, and the first boss 11 and the second boss 21 are arranged in a staggered manner in the circumferential direction.
[0060] The first boss 11 extending in the radial direction is arranged on the outer wall of the inner layer core 1, and the second boss 21 extending in the radial direction is arranged on the inner wall of the middle layer core 2, and the first boss 11 and the second boss 21 are arranged in a staggered manner in the circumferential direction, so that the circumferential sides of each first boss 11 are both the second boss 21, and the circumferential sides of each second boss 21 are both the first boss 11, thereby enhancing the structural strength of the entire rotor core, especially the circumferential structural strength during rotation.
[0061] In some embodiments,
[0062] The first boss 11 is provided with a first limiting hole 111 extending in the axial direction, the second boss 21 is provided with a second limiting hole 211 extending in the axial direction, and the first damping material layer 4 fills the first limiting hole 111 and the second limiting hole 211.
[0063] The first limiting hole 111 is arranged on the first boss 11, and the second limiting hole 211 is arranged on the second boss 21, and the first damping material layer 4 fills the first limiting hole 111 and the second limiting hole 211, and the first damping material layer 4 also fills between the inner layer core 1 and the middle layer core 2, so that the structural stability between the inner layer core 1, the first damping material layer 4 and the middle layer core 2 is stronger, and the arrangement of the first limiting hole 111 and the second limiting hole 211 and the filling of the first damping material layer 4 make the structural strength between the three more stable in the radial direction.
[0064] In some embodiments,
[0065] The middle layer core 2 is provided with a third boss 22 extending in the radial direction on the outer wall, and the outer layer core 3 is provided with a fourth boss 31 extending in the radial direction on the inner wall, and the third boss 22 and the fourth boss 31 are arranged in a staggered manner in the circumferential direction.
[0066] The third protrusion 22 radially extends on the outer wall of the middle layer core 2, and the fourth protrusion 31 radially extends on the inner wall of the outer layer core 3, the third protrusion 22 and the fourth protrusion 31 are circumferentially staggered, so that the circumferential two sides of each third protrusion 22 are the fourth protrusions 31, and the circumferential two sides of each fourth protrusion 31 are the third protrusions 22, which can enhance the structural strength of the entire rotor core, especially the circumferential structural strength when rotating.
[0067] In some embodiments,
[0068] The third protrusion 22 is provided with an axially penetrating third limiting hole 221, the fourth protrusion 31 is provided with an axially penetrating fourth limiting hole 311, and the second damping material layer 6 fills the third limiting hole 221 and the fourth limiting hole 311.
[0069] The third limiting hole 221 is arranged on the third protrusion 22, and the fourth limiting hole 311 is arranged on the fourth protrusion 31, and the second damping material layer 6 is filled in the third limiting hole 221 and the fourth limiting hole 311, and the second damping material layer 6 is also filled between the middle layer core 2 and the outer layer core 3, so that the structural stability between the middle layer core 2, the second damping material layer and the outer layer core 3 is stronger, and the third limiting hole 221 and the fourth limiting hole 311 are arranged and filled with the second damping material layer 6, so that the structural strength between them in the radial direction is more stable.
[0070] In some embodiments,
[0071] The outer wall of the outer layer core 3 is provided with a radially extending fifth protrusion 32, the fifth protrusion 32 is provided with a plurality of fifth protrusions 32, and is uniformly distributed along the outer wall of the outer layer core 3 in the circumferential direction, and the magnetic tiles 7 are attached between adjacent fifth protrusions 32.
[0072] The radially extending fifth protrusion 32 is arranged on the outer wall of the outer layer core 3, a plurality of fifth protrusions 32 are arranged in the circumferential direction, and one magnetic tile 7 is attached between every two fifth protrusions 32, so as to form a rotor core with a magnetic tile 7 structure; the arrangement of the fifth protrusion 32 can enhance the convenience of installation of the magnetic tile 7 and the structural stability during use.
[0073] In some embodiments,
[0074] The injection molding material layer 5 is filled between adjacent magnetic tiles 7, the injection molding material layer 5 protrudes from the rotor core in the axial direction, and the protruding part is spaced apart from the part protruding from the rotor core of the second damping material layer 6.
[0075] Between the adjacent magnetic tiles 7, specifically in the groove body surrounded by the adjacent magnetic tiles 7 and the fifth boss 32, the injection plastic is filled to form the injection plastic layer 5, which is equivalent to injection molding of the rotor assembly to form a complete damping rotor; wherein the injection plastic layer 5 also protrudes from the axial end face of the rotor core, so that the axial end face of the magnetic tile 7 is sealed.
[0076] The part of the injection plastic layer 5 protruding from the axial end face of the rotor core is arranged in a spaced manner with the protruding part of the second damping material layer 6, and the injection plastic layer 5 and the second damping material layer 6 do not interfere with each other in the damping process, thereby improving the frequency range of noise reduction; wherein the protruding height of the protruding part of the injection plastic layer 5 is greater than the protruding height of the first damping material layer 4 and the second damping material layer 6, so that the injection plastic layer 5 protects the first damping material layer 4 and the second damping material layer 6, thereby improving the safety and service life in use.
[0077] In summary, the rotor core of the present application adopts at least three radially segmented annular cores, forms two sets of damping material layers that are not connected to each other between the adjacent cores, and is combined and nested into one body by injecting rubber materials with the same or different materials or hardness. The outermost surface of the outermost core 3 matches the magnetic tile 7, and through injection molding, a complete damping rotor is formed, thereby achieving a wider frequency band noise reduction effect.
[0078] As shown in the specific structure Figure 5 The rotor core has an inner layer, a middle layer, and an outer layer. The inner core 1d has a shaft hole in the center hole and is matched with the shaft. A plurality of first bosses 11 are arranged on the outer wall surface of the inner core 1d. Each first boss 11 is provided with a first limiting hole 111 for distributing the glue. The inner wall surface of the middle core 2 is provided with a plurality of second bosses 21. Each second boss 21 is provided with a second limiting hole 211 for distributing the glue. The number of the first bosses on the inner core 1d is equal to the number of the second bosses 21 on the middle core 2, and they are arranged in a staggered manner. The first damping material layer 4 fills the gap between the outer circle of the inner core 1d and the inner circle of the middle core 2, and fills the first limiting hole 111 and the second limiting hole 211. The first damping material layer 4 protrudes from the two axial end faces of the inner core 1d and the middle core 2, and the overall cross-sectional shape forms an I-shaped structure. This part is collectively referred to as the first damping system.
[0079] The outer wall surface of the middle core 2 is provided with a plurality of third bosses 22, and each third boss 22 is provided with a third limiting hole 221 for distributing the glue. The inner wall surface of the outer core 3 is provided with a plurality of fourth bosses 31, and each fourth boss 31 is provided with a fourth limiting hole 311 for distributing the glue. The number of the third bosses 22 on the inner core 1d is equal to the number of the fourth bosses 31 on the outer core 3, and they are arranged in a staggered manner. The second damping material layer 6 fills the gap between the outer circle of the middle core 2 and the inner circle of the outer core 3, and fills the third limiting hole 221 and the fourth limiting hole 311. The second damping material layer 6 protrudes from the two axial end faces of the outer core 3 and the middle core 2, and the overall cross-sectional shape forms an I-shaped structure. This part is collectively referred to as the second damping system.
[0080] The first damping material layer 4 and the second damping material layer 6 also have gaps between the protruding portions and are not in direct contact, and belong to two independent damping systems.
[0081] The outer wall surface of the outer core 3 is provided with fifth protrusions 32, and the number of the fifth protrusions 32 is consistent with the number of the magnetic tiles 7. One magnetic tile 7 is attached to the outer wall surface between every two adjacent fifth protrusions 32, so as to limit the magnetic tile 7. At the gap between the magnetic tile 7 and the fifth protrusion 32, the magnetic tile 7 and the outer ring of the outer core 3 are fixed by filling plastic material and wrapping the two end surfaces of the magnetic tile 7 and the outer corner of the magnetic tile 7.
[0082] The part of the plastic material axially protruding from the magnetic tile 7 has a gap with the second damping material layer 6. The end surface size of the first damping material layer 4 and the second damping material layer 6 is not higher than the end surface of the plastic material.
[0083] The materials and hardness of the first damping material layer 4 and the second damping material layer 6 can be the same or different, so as to process noise problems in different frequency bands.
[0084] According to another aspect of the present application, a brushless direct current motor is provided, which comprises the rotor assembly as described above.
[0085] It is easy for those skilled in the art to understand that the above-mentioned embodiments can be freely combined and superimposed without conflict.
[0086] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application. The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1. A rotor assembly characterized by, The rotor core is composed of at least three layers of rings, i.e., an inner core (1), a middle core (2), and an outer core (3), which are arranged in sequence from inside to outside. The damping layer is composed of at least a first damping material layer (4) and a second damping material layer (6), which are arranged in sequence and filled between the inner core (1) and the middle core (2) and between the middle core (2) and the outer core (3), respectively.
2. The rotor assembly according to claim 1, wherein: the first damping material layer (4) protrudes axially from the rotor core and has a thickness greater than the gap between the inner core (1) and the middle core (2) in the radial direction of the rotor core; the second damping material layer (6) protrudes axially from the rotor core and has a thickness greater than the gap between the middle core (2) and the outer core (3) in the radial direction of the rotor core; and the protruding portions of the first and second damping material layers (4, 6) are arranged in sequence.
3. The rotor assembly according to claim 1 or 2, wherein: the inner core (1) is provided with radially extending first bosses (11) on the outer wall thereof, the middle core (2) is provided with radially extending second bosses (21) on the inner wall thereof, and the first bosses (11) and the second bosses (21) are arranged in an alternating manner in the circumferential direction.
4. The rotor assembly according to claim 3, wherein: the first bosses (11) are provided with axially extending first limiting holes (111), the second bosses (21) are provided with axially extending second limiting holes (211), and the first damping material layer (4) is filled in the first limiting holes (111) and the second limiting holes (211).
5. The rotor assembly according to claim 1, wherein: the middle core (2) is provided with radially extending third bosses (22) on the outer wall thereof, the outer core (3) is provided with radially extending fourth bosses (31) on the inner wall thereof, and the third bosses (22) and the fourth bosses (31) are arranged in an alternating manner in the circumferential direction.
6. The rotor assembly according to claim 5, wherein: the third bosses (22) are provided with axially extending third limiting holes (221), the fourth bosses (31) are provided with axially extending fourth limiting holes (311), and the second damping material layer (6) is filled in the third limiting holes (221) and the fourth limiting holes (311).
7. The rotor assembly according to claim 1, wherein: the outer core (3) is provided with radially extending fifth bosses (32) on the outer wall thereof, the fifth bosses (32) are arranged in a plurality and distributed uniformly in the circumferential direction of the outer wall of the outer core (3), and the magnetic tiles (7) are arranged between adjacent fifth bosses (32).
8. The rotor assembly according to claim 7, wherein: The injection plastic layer (5) is filled between the adjacent magnetic tiles (7), protrudes the rotor core axially, and is spaced from the part of the second damping material layer (6) protruding the rotor core.
9. The rotor assembly of claim 1, wherein: The first damping material layer (4) and the second damping material layer (6) are made of different rubber materials.
10. A brushless DC motor, characterized by A rotor assembly as claimed in any one of claims 1 to 9.