Bearing seat and motor

Abstract

The utility model discloses a bearing seat and a motor, and relates to the technical field of motors, the bearing seat comprises a bottom and a connecting portion arranged at the bottom in a protruding mode, the bearing seat is provided with a shaft hole penetrating through the two ends of the bearing seat in the axial direction, and the shaft hole penetrates through the bottom and the connecting portion. The connecting part comprises two first connecting sections and a second connecting section arranged between the two first connecting sections, each first connecting section is provided with a first hole section, each second connecting section is provided with a second hole section, the inner diameter of each first hole section is larger than that of each second hole section, and the first hole sections are used for mounting a bearing; the outer diameter of the second connecting section is larger than that of the first connecting section so as to be in interference fit with the stator, a groove is formed in the position, corresponding to the junction of the first hole section and the second hole section, of the outer wall face of the connecting part so that a direct stress transmission path of the second connecting section can be broken, stress cannot be easily transmitted to the first hole section, and deformation of the first hole section is avoided. And the outer ring of the bearing is caused to slide due to interference with the bearing arranged in the inner ring.

Description

Technical Field

[0001] This utility model relates to the field of motor technology, and in particular to a bearing housing and a motor. Background Technology

[0002] External rotor motors (ECMs) are highly favored in the market due to their superior energy efficiency, high operating efficiency, intelligent control capabilities, and ability to provide high torque and high power output. These motors typically employ a radial interference fit between the stator core and bearing housing. This ensures that the stator assembly remains stable and does not shift during operation or in extreme situations such as accidental drops. However, this design causes the internal dimensions of the bearing housing to shrink under stress, increasing the risk of the bearings being compressed and damaged during installation.

[0003] In related technologies, methods are employed to reduce the bonding force between the stator core and the bearing housing, thereby mitigating the impact of dimensional changes caused by interference fits on the bearing. However, this weakens the connection strength between stator components, and in some cases, improper adjustment of the bonding force may even lead to an increase in the bearing housing diameter, resulting in slippage of the bearing outer ring. Utility Model Content

[0004] The main purpose of this invention is to propose a bearing housing and a motor, which aims to solve the problem that the bearing housing is easily deformed due to compression when the stator core and the bearing housing are assembled by radial interference fit.

[0005] To achieve the above objectives, the bearing housing proposed in this utility model includes a bottom and a connecting portion protruding from the bottom. The bearing housing has shaft holes extending through both ends in its axial direction. The shaft holes pass through the bottom and the connecting portion. The connecting portion includes two first connecting sections and a second connecting section disposed between the two first connecting sections. The first connecting sections are provided with a first hole section, and the second connecting section is provided with a second hole section. The inner diameter of the first hole section is set to be larger than the inner diameter of the second hole section for bearing installation.

[0006] Wherein, the outer diameter of the second connecting segment is set to be larger than the outer diameter of the first connecting segment, and the outer wall surface of the connecting part is provided with at least one groove, the groove extending along the circumference of the bearing seat and corresponding to the junction of the first hole segment and the second hole segment.

[0007] In one embodiment, the groove is configured as an annular groove; or,

[0008] The groove is provided in multiple ways, and the multiple grooves are arranged at intervals in the circumferential direction of the bearing seat.

[0009] In one embodiment, the groove is provided on the second connecting segment.

[0010] In one embodiment, the groove is disposed at the junction of the second connecting segment and the first connecting segment.

[0011] In one embodiment, of the two first connecting segments, the wall thickness of the first connecting segment located away from the bottom is H1, and the wall thickness of the other first connecting segment is H2, where H1 < H2;

[0012] The groove is located on the side of the second connecting segment away from the bottom.

[0013] In one embodiment, the groove depth is A, where 0.2 ≤ A / H1 ≤ 1.5.

[0014] In one embodiment, the groove width is B, where 0.2 ≤ B / H1 ≤ 2.

[0015] In one embodiment, the groove is provided on the first connecting segment;

[0016] The distance between the groove and the inner edge of the first hole section in the bearing seat is L in the axial direction, and the wall thickness of the first connecting section corresponding to the groove is H, where L / H≤1.5.

[0017] This utility model also provides a motor, the motor comprising:

[0018] Bearing housing; and,

[0019] The stator is sleeved around the periphery of the connecting part and is interference-fitted with the second connecting section;

[0020] The bearing housing includes a bottom and a connecting portion protruding from the bottom. The bearing housing has shaft holes extending through both ends in its axial direction. The shaft holes pass through the bottom and the connecting portion. The connecting portion includes two first connecting sections and a second connecting section disposed between the two first connecting sections. The first connecting sections are provided with first hole sections, and the second connecting sections are provided with second hole sections. The inner diameter of the first hole section is set to be larger than the inner diameter of the second hole section for bearing installation.

[0021] Wherein, the outer diameter of the second connecting segment is set to be larger than the outer diameter of the first connecting segment, and the outer wall surface of the connecting part is provided with at least one groove, the groove extending along the circumference of the bearing seat and corresponding to the junction of the first hole segment and the second hole segment.

[0022] In one embodiment, the motor includes an electronically commutated motor.

[0023] In this invention, the second connecting section of the bearing housing has a larger outer diameter than the first connecting section. The connecting part is used to connect with the stator, and the second connecting section has an interference fit with the stator. The second hole section, due to its smaller inner diameter, may experience greater assembly pressure, leading to localized stress concentration. By providing a groove on the outer wall of the connecting part, corresponding to the junction of the first and second hole sections, the direct stress transmission path of the second connecting section can be effectively interrupted. This allows the stress to be dispersed or partially absorbed at the groove, rather than being completely transmitted to the first hole section. Even when the second hole section experiences stress due to the interference fit, the stress will not easily propagate to the first hole section, preventing deformation of the first hole section, interference with the installed bearing, or slippage of the bearing outer ring. This reduces the risk of bearing damage and slippage due to stress concentration. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0025] Figure 1 A schematic diagram of the structure of an embodiment of the bearing housing and stator assembly provided by this utility model;

[0026] Figure 2 A schematic diagram of the structure of an embodiment of the bearing housing provided by this utility model;

[0027] Figure 3 for Figure 2 Front view of the bearing housing;

[0028] Figure 4 for Figure 3 A cross-sectional view of the bearing housing and bearing assembly;

[0029] Figure 5 for Figure 3 A cross-sectional view of the bearing housing;

[0030] Figure 6 for Figure 5 A magnified view of a section at point A in the middle;

[0031] Figure 7 An enlarged schematic diagram of point A in another embodiment of the bearing housing provided by this utility model.

[0032] Explanation of icon numbers:

[0033] 100. Bearing housing; 1. Bottom; 2. Connecting part; 21. First connecting section; 22. Second connecting section; a. Shaft hole; a1. First hole section; a2. Second hole section; b. Groove;

[0034] 200, stator; 300, bearing.

[0035] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0036] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0037] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0038] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0039] This utility model proposes a bearing housing, which aims to solve the problem that the bearing housing is prone to deformation due to compression when the stator core and the bearing housing are assembled by radial interference fit.

[0040] Please see Figures 1 to 4In one embodiment of the present invention, the bearing housing 100 includes a bottom 1 and a connecting portion 2 protruding from the bottom 1. The bearing housing 100 has shaft holes a passing through both ends in its axial direction. The shaft holes a pass through the bottom 1 and the connecting portion 2. The connecting portion 2 includes two first connecting segments 21 and a second connecting segment 22 disposed between the two first connecting segments 21. The first connecting segment 21 is provided with a first hole segment a1, and the second connecting segment 22 is provided with a second hole segment a2. The inner diameter of the first hole segment a1 is set to be larger than the inner diameter of the second hole segment a2 for mounting the bearing 300. The outer diameter of the second connecting segment 22 is set to be larger than the outer diameter of the first connecting segment 21. The outer wall surface of the connecting portion 2 is provided with at least one groove b. The groove b extends along the circumference of the bearing housing 100 and is disposed at the junction of the first hole segment a1 and the second hole segment a2.

[0041] It should be noted that the bearing housing 100 includes the bottom 1 and the connecting part 2. The bottom 1 has a large bottom surface, which facilitates installation with other components inside the motor. The connecting part 2 is configured as a protruding post for the stator 200 to be installed. The stator 200 is sleeved on the connecting part 2 and is interference-fitted with the connecting part 2.

[0042] It is understood that the stator 200 is not interference-fitted with all mating surfaces of the connecting part 2. The outer diameter of the second connecting section 22 is set to be larger than the outer diameter of the first connecting section 21. When the stator 200 is sleeved on the connecting part 2, the stator 200 and the second connecting section 22 are configured to be interference-fitted. The stress generated by the connecting part 2 mainly acts on the second connecting section 22.

[0043] It should also be noted that the outer diameter of the second connecting segment 22 is set to be larger than the outer diameter of the first connecting segment 21. The second connecting segment 22 may be set to have a circular cross-section, and the outer peripheral wall of the second connecting segment 22 is integrally interference-fitted with the inner peripheral wall of the stator 200. Of course, the second connecting segment 22 may also be partially interference-fitted with the inner peripheral wall of the stator 200. The specific design can be based on the actual situation, and this specification does not limit this embodiment.

[0044] The groove b extends circumferentially along the bearing housing 100 and is located at the junction of the first hole segment a1 and the second hole segment a2. The groove b interrupts the direct stress transmission path, allowing the stress to be dispersed or absorbed in time at the groove b, thereby reducing the dimensional impact of the stator 200 and the bearing housing 100 on the first hole segment a1 after interference fit.

[0045] It is understood that the groove b is provided at the junction of the first hole segment a1 and the second hole segment a2. The groove b can be located on the first hole segment a1 adjacent to the second hole segment a2, or on the second hole segment a2 adjacent to the first hole segment a1, or at the junction of the first hole segment a1 and the second hole segment a2. Regardless of the specific location of the groove b in this region, the stress acting on the first hole segment a1 can be significantly reduced, preventing deformation.

[0046] The groove b is provided at least one, that is, the groove b can be one, two, or even more. When the groove b is provided as one, the groove b can be provided near the first hole segment a1 with a greater risk of deformation, that is, near the first hole segment a1 with a smaller wall thickness.

[0047] When the groove b is set to two, it can be set near the second hole segment a2 of the corresponding two first hole segments a1, which can play a role in preventing the deformation of the two first hole segments a1 at the same time.

[0048] In the technical solution of this utility model, by setting the outer diameter of the second connecting section 22 of the bearing housing 100 to be larger than that of the first connecting section 21, the connecting part 2 is used to sleeve with the stator 200. The second connecting section 22 and the stator 200 are interference-fitted to keep the bonding force between the iron core and the bearing housing 100 basically unchanged. The second hole section a2 may be subjected to large assembly pressure due to its small inner diameter, resulting in local stress concentration. By setting the groove b on the outer wall surface of the connecting part 2, and setting it at the junction of the first hole section a1 and the second hole section a2, the direct stress transmission path of the second connecting section 22 can be effectively interrupted, so that the stress is dispersed or partially absorbed at the groove b, instead of being completely transmitted to the first hole section a1. Even when the second hole section a2 is stressed due to the interference fit, the stress will not easily propagate to the first hole section a1, avoiding deformation of the first hole section a1 and interference with the bearing 300 installed inside, or causing the outer ring of the bearing 300 to slide, reducing the risk of bearing 300 damage and slippage due to stress concentration.

[0049] Specifically, in some embodiments, multiple grooves b are provided, and the multiple grooves b are arranged at intervals in the circumferential direction of the bearing seat 100.

[0050] By setting multiple spaced grooves b, the stress transmission path can be interrupted more effectively, reducing the possibility of local stress concentration, while also increasing the elastic deformation capacity of the outer wall of the bearing seat 100.

[0051] In other embodiments, the groove b is configured as an annular groove.

[0052] The groove b is set as an annular shape. Since the annular groove is continuous in shape, it can uniformly disperse and absorb stress within a 360-degree range, thereby effectively preventing damage caused by local stress concentration.

[0053] In contrast, if the groove b is not continuous, stress may concentrate on the uncovered portion, increasing the risk of damage to that area.

[0054] Furthermore, the annular groove is designed as a continuous shape, so that the stress is evenly distributed and there will be no local deformation caused by uneven stress, thus maintaining the overall mechanical stability of the bearing housing 100.

[0055] Furthermore, in this embodiment, the second connecting segment 22 is provided with the groove b.

[0056] It should be noted that, since the connecting part 2 is sleeved with the stator 200, when the outer diameters of the first connecting segment 21 and the second connecting segment 22 of the connecting part 2 are the same, since the inner diameter of the first hole segment a1 is set to be greater than the inner diameter of the second hole segment a2, the wall thickness of the first hole segment a1 is less than the wall thickness of the second hole segment a2. Therefore, relatively speaking, the deformation resistance of the second connecting segment 22 is greater than that of the first connecting segment 21.

[0057] Understandably, the first hole segment a1 has a smaller wall thickness, making it relatively more fragile and susceptible to damage. If the groove b is provided on the first connecting segment 21, it may further weaken its structural strength and increase the risk of breakage. Conversely, providing the groove b on the second connecting segment 22 can both disperse stress and not significantly affect the overall structural stability of this part.

[0058] Setting the groove b on the second connecting section 22 to interrupt the stress transmission path will not seriously affect the assembly quality and precision of the entire component, thus ensuring the stability and reliability of the bearing 300 during installation, while reducing the potential negative impact on other components.

[0059] Further, please refer to Figures 4 to 6 In this embodiment, the groove b is disposed at the junction of the second connecting segment 22 and the first connecting segment 21.

[0060] It is understandable that the junction of the second connecting segment 22 and the first connecting segment 21 is a region of abrupt change in cross-section and a location of stress concentration. Setting the groove b at this location, by removing material to form a flexible region, allows the stress flow lines to be redistributed, which can reduce the stress peak value in the abrupt change region, interrupt the stress transmission path, reduce local stress concentration, and avoid structural damage caused by excessive stress.

[0061] During the interference fit of the second connecting section 22, the groove b can also absorb the additional assembly stress caused by tolerance fluctuations. When the difference in the coefficients of thermal expansion between the stator 200 and the bearing housing 100 causes micro-displacement, the groove b provides deformation compensation space to prevent the first connecting section 21 from undergoing plastic deformation.

[0062] Specifically, please refer to Figure 5 and Figure 6 In this embodiment, of the two first connecting segments 21, the wall thickness of the first connecting segment 21 located away from the bottom 1 is H1, and the wall thickness of the other first connecting segment 21 is H2, where H1 < H2; the groove b is located on the side of the second connecting segment 22 away from the bottom 1.

[0063] It is understandable that H1 < H2, meaning the first connecting segment 21, located further away from the bottom 1, is weaker and more susceptible to deformation. Placing the groove b on this side helps to distribute stress. While ensuring the strength of the bearing housing 100, providing the groove b avoids stress concentration in the area most prone to deformation.

[0064] Specifically, in this embodiment, the groove depth of the groove b is A, and 0.2≤A / H1≤1.5.

[0065] It is understandable that when the groove b is too shallow (groove depth / wall thickness < 0.2), it cannot effectively form a geometric discontinuity feature, resulting in the stress flow lines not being fully redistributed. At this time, the "elastic isolation zone" function of the groove b fails, and the assembly or working stress will still be transmitted to the thinner wall area through the rigid connection, increasing the risk of fatigue cracking in the first connection segment 21.

[0066] If the groove b is too deep (groove depth / wall thickness > 1.5), the remaining wall thickness will be insufficient (e.g., when the original wall thickness is 3mm, only 1.5mm remains when the groove depth is 4.5mm), which will significantly reduce the structural load-bearing capacity.

[0067] Therefore, when the ratio of the groove depth of the groove b to the wall thickness of the first connecting section 21 is set to ≥0.2, the groove b can effectively form an elastic deformation zone, releasing assembly stress through material removal; when the ratio is ≤1.5, the excessive depth of the groove b can be avoided, which would lead to excessive weakening of the effective load-bearing section of the first connecting section 21.

[0068] Specifically, in this embodiment, the groove width of the groove b is B, and 0.2≤B / H1≤2.

[0069] The groove width of the groove b is too narrow (B / H1<0.2), which will create a sharp geometric abrupt change on the surface of the connecting part 2, resulting in an increase in the stress concentration factor at the bottom of the groove and increasing the risk of crack initiation. In terms of processing and manufacturing, it is difficult for the cutting tool to enter the narrow groove for precision machining, which easily produces burrs or dimensional deviations.

[0070] An excessively wide groove b (B / H1 > 2) will form a "weakening zone," leading to a decrease in stiffness in adjacent areas, structural stiffness deterioration, and inducing resonance under alternating loads. Furthermore, an excessively wide groove increases material removal, making it prone to shrinkage defects in the casting process, increasing scrap rate, and reducing material utilization.

[0071] Setting the B / H1 ratio between 0.2 and 2 ensures that the groove b can effectively release interference fit stress without excessively weakening the structural load-bearing capacity.

[0072] In some embodiments, please refer to Figure 7 The first connecting segment 21 is provided with the groove b; the distance between the groove b and the inner edge of the first hole segment a1 in the bearing seat 100 in the axial direction is L, and the wall thickness of the first connecting segment 21 corresponding to the groove b is H, where L / H≤1.5.

[0073] It is understandable that although the wall thickness of the first connecting segment 21 is small, the L / H ratio is constrained to be less than or equal to 1.5 to ensure that the axial distance between the groove b and the edge of the bearing 300 hole is always within 1.5 times the wall thickness. This avoids excessive local stress concentration in the middle of the first connecting segment 21 due to the groove b being too far from the hole edge, and also ensures that the first connecting segment 21 as a whole will not be affected by excessive stress and deform.

[0074] This utility model also proposes an electric motor, which includes a stator 200 and a bearing housing 100. The stator 200 is sleeved on the periphery of the connecting part 2 and is interference-fitted with the second connecting section 22. The specific structure of the bearing housing 100 is as described in the above embodiments. Since this electric motor adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.

[0075] Specifically, in one embodiment, the motor includes an electronically commutated motor, namely an ECM external rotor motor. It should be noted that an external rotor motor refers to a structure in which the rotor is on the outside and the stator 200 is inside. ECM is used in applications that require high efficiency and compact structure, such as fans or pumps.

[0076] The stator 200 is fitted around the connecting portion 2 and has an interference fit with the second connecting section 22. A rigid connection between the stator 200 and the bearing housing 100 is achieved through radial clamping force, resisting the centrifugal force and electromagnetic force generated by the high-speed rotation of the rotor, and preventing circumferential or axial displacement of the stator 200 during operation. Furthermore, the interference fit reduces the gap between the stator 200 and the bearing housing 100, avoiding fretting wear and resonance caused by loose fit. Therefore, the interference fit can improve the structural rigidity and operational stability of the ECM external rotor motor. By providing the groove b, stress release is actively guided, which is suitable for addressing assembly stress concentration problems in external rotor motors caused by interference fit or thermal expansion.

[0077] The above description is merely an exemplary embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. A bearing housing, characterized in that, The bearing housing includes a bottom and a connecting portion protruding from the bottom. The bearing housing has shaft holes extending through both ends in its axial direction. The shaft holes pass through the bottom and the connecting portion. The connecting portion includes two first connecting sections and a second connecting section disposed between the two first connecting sections. The first connecting sections are provided with first hole sections, and the second connecting sections are provided with second hole sections. The inner diameter of the first hole section is set to be larger than the inner diameter of the second hole section for bearing installation. Wherein, the outer diameter of the second connecting segment is set to be larger than the outer diameter of the first connecting segment, and the outer wall surface of the connecting part is provided with at least one groove, the groove extending along the circumference of the bearing seat and corresponding to the junction of the first hole segment and the second hole segment.

2. The bearing housing as described in claim 1, characterized in that, The groove is configured as an annular groove; or... The groove is provided in multiple ways, and the multiple grooves are arranged at intervals in the circumferential direction of the bearing seat.

3. The bearing housing as described in claim 1, characterized in that, The groove is provided on the second connecting segment.

4. The bearing housing as described in claim 3, characterized in that, The groove is located at the junction of the second connecting segment and the first connecting segment.

5. The bearing housing as described in claim 3, characterized in that, Of the two first connecting segments, the wall thickness of the first connecting segment located away from the bottom is H1, and the wall thickness of the other first connecting segment is H2, where H1 < H2. The groove is located on the side of the second connecting segment away from the bottom.

6. The bearing housing as described in claim 5, characterized in that, The groove depth is A, where 0.2 ≤ A / H1 ≤ 1.

5.

7. The bearing housing as described in claim 5, characterized in that, The groove width is B, and 0.2≤B / H1≤2.

8. The bearing housing as described in claim 1, characterized in that, The groove is provided on the first connecting segment; The distance between the groove and the inner edge of the first hole section in the bearing seat is L in the axial direction, and the wall thickness of the first connecting section corresponding to the groove is H, where L / H≤1.

5.

9. An electric motor, characterized in that, include: The bearing housing as claimed in any one of claims 1 to 8; and, The stator is sleeved around the periphery of the connecting part and is interference-fitted with the second connecting section.

10. The motor as described in claim 9, characterized in that, The motor includes an electronically commutated motor.

Images