Brushless motor with axial bearing structure

Abstract

The utility model discloses a brushless motor with an axial bearing structure. The brushless motor comprises a housing; the shell cover is connected to one end of the shell, and a first inner space is formed between the shell cover and the shell; a stator disposed in the first inner space; one part of the rotor is arranged in the first inner space and surrounded by the stator, and the other part of the rotor penetrates out of the shell; one bearing is connected to the shell, and the other bearing is connected to the shell cover and used for supporting the rotor; the elastic support is arranged in the first inner space, is connected among the shell, the stator, the rotor and one of the bearings and is used for supporting one of the bearings; the rigid support and the elastic support are arranged at intervals, the rigid support is arranged in the first inner space, one end of the rigid support is connected between the shell cover and the other bearing, and the other end of the rigid support protrudes out of the shell cover and is used for supporting the other bearing; therefore, the technical problem that the axial force bearing effect of the deep groove ball bearing is poor is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of brushless motors, in particular to a brushless motor with an axial bearing structure. Background Art

[0002] In the micro motor industry, especially BLDC motors, since the electronic commutation switch replaces the brush commutator, it is called a brushless motor;

[0003] The structure of a brushless motor generally includes: a housing; a housing cover connected to one end of the housing and forming a first inner space with the housing; a stator arranged in the first inner space; a rotor, a part of which is arranged in the first inner space and surrounded by the stator, and the other part of which passes through the housing; two bearings, one of which is connected to the housing and the other is connected to the housing cover, for supporting the rotor; two retaining springs, which are connected to the rotor at intervals and are used to limit the bearings; and a corrugated gasket, which is cushioned between the housing cover and one of the bearings;

[0004] The rotor includes: a rotating shaft, which is arranged in the first inner space and one end of which passes through the housing, and the rotating shaft is supported by a bearing; a rotor core, which is arranged in the first inner space and connected to the rotating shaft; and a magnetic steel, which is arranged in the first inner space and connected to the rotor core;

[0005] Since the electronic commutation switch replaces the brush commutator, the main source of noise in the brushless motor has changed from the brush commutator to the operating noise of the bearing. Therefore, most manufacturers have selected deep groove ball bearings as the rotor support of micro BLDC motors to replace the oil-containing bearings in conventional brush motors.

[0006] The structure of deep groove ball bearings is relatively simple, the cost is relatively low, the noise is excellent, and the installation accuracy is not very strict;

[0007] The disadvantage of deep groove ball bearings is that they can only bear axial forces that are smaller than radial loads, and the internal structure of deep groove ball bearings is a rolling fit between inner and outer ground raceways and steel balls, and the contact method is a point on each steel ball. Once there is a deviation during installation, resulting in a large stress on one side of the steel ball, or a sudden large axial force when bearing, it is easy to cause defects and damage on the raceway or steel ball, thereby generating noise;

[0008] Therefore, a brushless motor with an axial bearing structure is needed. Utility Model Content

[0009] In view of the above-mentioned deficiencies existing in the related art, an object is to provide a brushless motor with an axial bearing structure to solve the technical problem in the related art that the deep groove ball bearing has a poor effect in bearing the axial force.

[0010] The technical solution to achieve the purpose is: a brushless motor with an axial bearing structure, comprising: a housing; a housing cover connected to one end of the housing and forming a first inner space with the housing; a stator arranged in the first inner space; a rotor, a part of which is arranged in the first inner space and surrounded by the stator, and the other part of which passes through the housing; and two bearings, one of which is connected to the housing and the other is connected to the housing cover, for supporting the rotor;

[0011] The rotor comprises: a rotating shaft, which is arranged in the first inner space and has one end passing through the housing, and the rotating shaft is supported by the bearing; a rotor core, which is arranged in the first inner space and connected to the rotating shaft; and a magnetic steel, which is arranged in the first inner space and connected to the rotor core;

[0012] It also includes: an elastic support, which is arranged in the first inner space and connected between the shell, the stator, the rotor and one of the bearings, and is used to support one of the bearings; and a rigid support, which is spaced apart from the elastic support, and the rigid support is arranged in the first inner space, one end of which is connected between the shell cover and the other bearing, and the other end protrudes from the shell cover, and is used to support the other bearing.

[0013] Further: the elastic support includes: a first part, arranged in the first inner space, arranged between the housing, the rotor and the bearing; and a second part, arranged between the first part, the rotating shaft and the bearing, for elastically supporting the bearing.

[0014] Further: the first part includes: a first support, which is arranged in the first inner space, contacts the shell, and the middle part surrounds the rotating shaft and is spaced apart from the rotating shaft; and a first stopper, connected to the rotating shaft, arranged between the rotor core and the first support, and a first gap is provided between the first stopper and the first support.

[0015] Further: the second part is a first elastic member, and the first elastic member is arranged between the first support, the rotating shaft, the bearing and the first stopper, and is used for elastically supporting the bearing.

[0016] Further: the first elastic member is a cylindrical spring.

[0017] Further: the elastic support includes: a third part, arranged in the first inner space, arranged between the shell, the rotor and the bearing; and a fourth part, arranged between the shell, the rotating shaft and the bearing, used to elastically support the bearing.

[0018] Further: the third part includes: a second support, which is arranged in the first inner space, contacts the shell, and the middle part surrounds the rotating shaft and is spaced apart from the rotating shaft; and a second stopper, connected to the rotating shaft, arranged between the rotor core and the bearing, partially surrounded by the middle part of the second support, and a second gap is provided between the second stopper and the second support.

[0019] Further: the fourth part is a second elastic member, the second elastic member is arranged between the housing, the rotating shaft and the bearing, and is spaced apart from the second stop member, for elastically supporting the bearing.

[0020] Further: the second elastic member is a corrugated gasket.

[0021] Further: the rigid support includes: a third support, one end of which is connected between the shell cover and another of the bearings, and the other end protrudes from the shell cover, and a second inner space is provided between the third support and the rotating shaft and the bearing; and a pressure-bearing member, which is arranged in the second inner space, and the pressure-bearing member contacts the rotating shaft and the third support.

[0022] Further: the pressure-bearing member is a steel ball.

[0023] The above technical scheme has the following beneficial effects: a brushless motor with an axial bearing structure is provided with elastic support and hard support compared with the related art; the elastic support is arranged in the first inner space, connected between the housing, the stator, the rotor and one of the bearings, and is used to support one of the bearings; the hard support and the elastic support are arranged at intervals, and the hard support is arranged in the first inner space, one end of which is connected between the shell cover and the other bearing, and the other end protrudes from the shell cover, and is used to support the other bearing; the bearing is reliably supported in the axial direction, the effect of bearing axial force is improved, and the bearing is protected; thereby overcoming the technical problem that the deep groove ball bearing has a poor effect of bearing axial force, achieving the technical effect of being able to form axial support and improving the bearing axial force, and having practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a partial cross-sectional view of the general assembly;

[0025] Figure 2 for Figure 1 A partial cross-sectional view after removing the stator and rotor;

[0026] Figure 3 It is one of the partial enlarged schematic diagrams of the elastic support;

[0027] Figure 4 The second is a partial enlarged schematic diagram of the elastic support;

[0028] Figure 5 It is a partial cross-sectional view of a brushless motor in the prior art;

[0029] In the figure: 10. elastic support, 11. first support, 12. first stopper, 13. first gap, 14. first elastic member, 10-1. second support, 10-2. second stopper, 10-3. second gap, 10-4. second elastic member, 20. rigid support, 21. third support, 22. second inner space, 23. pressure-bearing member, 100. housing, 200. housing cover, 300. stator, 400. rotor, 401. rotating shaft, 402. rotor core, 403. magnetic steel, 500. bearing, 600. retaining spring, 700. corrugated gasket. DETAILED DESCRIPTION

[0030] In order to make the content easier to understand, the following is a further detailed description based on specific embodiments and in conjunction with the accompanying drawings;

[0031] A brushless motor with an axial bearing structure solves the technical problem that the deep groove ball bearing in the related art has a poor effect in bearing the axial force. It can be manufactured and used, and can form an axial support and improve the positive effect of bearing the axial force. The overall idea is as follows:

[0032] One implementation method:

[0033] like Figure 1 , Figure 2 , Figure 3 , Figure 4 As shown; a brushless motor with an axial bearing structure, comprising: a housing 100; a housing cover 200, connected to one end of the housing 100, forming a first inner space with the housing 100; a stator 300, arranged in the first inner space; a rotor 400, a part of which is arranged in the first inner space and surrounded by the stator 300, and the other part of which passes through the housing 100; and two bearings 500, one of which is connected to the housing 100, and the other of which is connected to the housing cover 200, for supporting the rotor 400;

[0034] The rotor 400 includes: a rotating shaft 401, which is arranged in the first inner space and one end of which passes through the housing 100, and the rotating shaft 401 is supported by the bearing 500; a rotor core 402, which is arranged in the first inner space and connected to the rotating shaft 401; and a magnetic steel 403, which is arranged in the first inner space and connected to the rotor core 402;

[0035] The invention also includes: an elastic support 10, which is arranged in the first inner space, connected between the housing 100, the stator 300, the rotor 400 and one of the bearings 500, and used to support one of the bearings 500; and a rigid support 20, which is arranged at a distance from the elastic support 10, and the rigid support 20 is arranged in the first inner space, one end of which is connected between the housing cover 200 and the other bearing 500, and the other end of which protrudes from the housing cover 200, and used to support the other bearing 500;

[0036] Specifically, during implementation, an elastic support 10 and a rigid support 20 are provided; the elastic support 10 is provided in the first inner space, connected between the housing 100, the stator 300, the rotor 400 and one of the bearings 500, and used to support one of the bearings 500; the rigid support 20 is spaced apart from the elastic support 10, and the rigid support 20 is provided in the first inner space, one end of which is connected between the housing cover 200 and another bearing 500, and the other end protrudes from the housing cover 200, and used to support another bearing 500; so that the bearing 500 is reliably supported in the axial direction, the effect of bearing the axial force is improved, and the bearing 500 is protected;

[0037] Another embodiment:

[0038] like Figure 1 , Figure 2 , Figure 3 As shown; in implementation, the elastic support 10 includes: a first part, which is arranged in the first inner space, and is arranged between the housing 100, the rotor 400 and the bearing 500; and a second part, which is arranged between the first part, the rotating shaft 401 and the bearing 500, and is used to elastically support the bearing 500;

[0039] The first part includes: a first support 11, which is arranged in the first inner space, contacts the housing 100, and surrounds the rotating shaft 401 in the middle part, and is spaced apart from the rotating shaft 401; and a first stopper 12, which is connected to the rotating shaft 401 and is arranged between the rotor core 402 and the first support 11, and a first gap 13 is formed between the first stopper 12 and the first support 11;

[0040] The second part is a first elastic member 14, which is disposed between the first support 11, the rotating shaft 401, the bearing 500 and the first stopper 12, and is used to elastically support the bearing 500;

[0041] The first support 11 is a circular ring structure after being projected from the shell 100 to the shell cover 200, which is conducive to limiting the first elastic member 14, so that the first elastic member 14 always stretches and contracts along the axial direction, and the elastic support and buffering effect of the first elastic member 14 is relatively good;

[0042] The first stopper 12 is a circular ring structure after being projected from the housing 100 to the housing cover 200, and is sleeved on the rotating shaft 401 and fixedly connected to the rotating shaft 401; the first stopper 12, the first support 11 and the rotating shaft 401 together limit the first elastic member 14, so that the first elastic member 14 always expands and contracts along the axial direction, and the elastic support and buffering effects of the first elastic member 14 are relatively good;

[0043] A first gap 13 is provided so that the first stopper 12 will not get stuck with the first support 11 when the rotor 400 moves axially, and the structural reliability is good;

[0044] The first elastic member 14 is a cylindrical spring, which is sleeved on the rotating shaft 401 and limited between the first support 11, the rotating shaft 401, the bearing 500 and the first stopper 12; one end of the first elastic member 14 contacts and abuts against the inner ring of the bearing 500, and the other end contacts and abuts against the first stopper 12; the elastic force of the first elastic member 14 can not only adjust the assembly gap between the components on the brushless motor, but also play a role of elastic support and buffer when bearing axial force, thereby protecting the bearing 500;

[0045] Another embodiment:

[0046] like Figure 4 As shown; when implemented, the elastic support 10 includes: a third part, which is arranged in the first inner space, and is arranged between the housing 100, the rotor 400 and the bearing 500; and a fourth part, which is arranged between the housing 100, the rotating shaft 401 and the bearing 500, and is used to elastically support the bearing 500;

[0047] The third part includes: a second support 10-1, which is arranged in the first inner space, contacts the housing 100, surrounds the rotating shaft 401 at its middle portion, and is spaced apart from the rotating shaft 401; and a second stopper 10-2, which is connected to the rotating shaft 401, is arranged between the rotor core 402 and the bearing 500, is partially surrounded by the middle portion of the second support 10-1, and has a second gap 10-3 between the second stopper 10-2 and the second support 10-1;

[0048] The fourth part is a second elastic member 10 - 4 , which is disposed between the housing 100 , the rotating shaft 401 and the bearing 500 , and is spaced apart from the second stopper 10 - 2 , and is used to elastically support the bearing 500 ;

[0049] The second support 10-1 is a circular ring structure after being projected from the housing 100 to the housing cover 200, forming a barrier to prevent the second stopper 10-2 from excessively shifting when the rotor 400 moves axially, pushing the bearing 500 and damaging the bearing 500;

[0050] The second stopper 10-2 has a T-shaped structure, the middle part of which is sleeved on the rotating shaft 401 and fixedly connected to the rotating shaft 401. One end of the second stopper 10-2 contacts and abuts against the inner ring of the bearing 500 to limit the bearing 500.

[0051] A second gap 10-3 is provided so that the second stopper 10-2 will not get stuck with the second support 10-1 when the rotor 400 moves axially, and the structural reliability is good;

[0052] The second elastic member 10-4 is a corrugated gasket. The elastic force of the corrugated gasket can not only adjust the assembly gap between the components of the brushless motor, but also play a role of elastic support and buffer when bearing axial force, thereby protecting the bearing 500.

[0053] Another embodiment:

[0054] like Figure 1 , Figure 2 As shown; when implemented, the rigid support 20 includes: a third support 21, one end of which is connected between the shell cover 200 and another bearing 500, and the other end protrudes from the shell cover 200, and a second inner space 22 is provided between the third support 21 and the rotating shaft 401 and the bearing 500; and a pressure member 23, which is arranged in the second inner space 22, and the pressure member 23 contacts the rotating shaft 401 and the third support 21;

[0055] The pressure bearing member 23 is a steel ball, which is in point contact with the third support 21 or the rotating shaft 401, not only forming support, but also having relatively small friction resistance with the rotating shaft 401 or the third support 21, and will not get stuck, and has good structural reliability;

[0056] Another embodiment:

[0057] like Figure 1 , Figure 2 , Figure 3 , Figure 4As shown; during implementation, an elastic support 10 and a rigid support 20 are provided; when the axial force is from left to right or from right to left, the rigid blocking of the rigid support 20 and the elastic support buffering of the elastic support 10 make the axial movement distance of the bearing 500 relatively small (the axial movement distance is smaller than the corresponding clearance of the selected model of the bearing 500 itself, and the clearance is common knowledge), thereby protecting the bearing 500, and the self-structure of the elastic support 10 and the rigid support 20 fully utilizes the space of the brushless motor without increasing the volume of the brushless motor;

[0058] Brushless motor structure in the prior art:

[0059] See Figure 5 The brushless motor comprises: a housing 100; a housing cover 200 connected to one end of the housing 100 and forming a first inner space with the housing 100; a stator 300 disposed in the first inner space; a rotor 400, a part of which is disposed in the first inner space and surrounded by the stator 300, and the other part of which passes through the housing 100; two bearings 500, one of which is connected to the housing 100 and the other of which is connected to the housing cover 200, for supporting the rotor 400; two retaining springs 600, which are connected to the rotor 400 at intervals and are used to limit the bearings 500; and a corrugated gasket 700, which is padded between the housing cover 200 and one of the bearings 500;

[0060] The housing 100, the housing cover 200, the stator 300, the rotor 400, the bearing 500 (deep groove ball bearing), the retaining ring 600 and the wave washer 700 are common structures in the prior art, which are not the inventive points of the present utility model, but are only for better description of the present utility model and for facilitating understanding of the technical solution of the present utility model;

[0061] In the prior art, a retaining spring 600 is used to limit the axial displacement of the rotor 400, and a corrugated gasket 700 is used as an elastic element to eliminate the axial clearance formed by the errors in the manufacturing and assembly of the parts of the entire brushless motor. Such a structure can only withstand a relatively small axial force. Once the axial force becomes larger (the axial force makes the axial movement distance greater than the corresponding clearance of the bearing 500 under the selected model), it is easy to cause damage to the inner and outer ring raceways or bearing balls of the bearing 500, and the bearing 500 will generate noise and its service life will also be reduced. Especially in micro motors (BLDC motors), due to their small size and limited internal space of the whole machine, the specifications and dimensions of the selected bearing 500 are also relatively small (the diameter of the bearing ball is small, the corresponding clearance under the selected model is relatively small, and the axial load-bearing capacity of the bearing ball is also relatively small, which is common knowledge), and it is easy to generate noise due to improper axial force.

[0062] The working principle is as follows: the elastic support 10 is arranged in the first inner space, connected between the housing 100, the stator 300, the rotor 400 and one of the bearings 500, and is used to support one of the bearings 500; the rigid support 20 is arranged at intervals from the elastic support 10, and is arranged in the first inner space, with one end connected between the housing cover 200 and another bearing 500, and the other end protruding from the housing cover 200, and is used to support another bearing 500; so that the bearing 500 is reliably supported in the axial direction, the effect of bearing the axial force is improved, and the bearing 500 is protected;

[0063] In the description, it should be understood that the terms "upper", "lower", "left", "right", "front", "back" and the like indicating directions or positional relationships are based on the positional relationships described in the drawings and are only for the convenience of description or simplified description, rather than indicating specific directions that must be possessed; the operation process described in the embodiments is not an absolute usage procedure and corresponding adjustments may be made in actual use;

[0064] Unless otherwise defined, the technical or scientific terms used herein shall have the usual meanings understood by persons with ordinary skills in the relevant field; the words "first", "second" and similar words used in the specification and claims do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one" or "a" do not necessarily indicate a quantity limitation, but indicate the existence of at least one, which needs to be determined according to the content of the embodiment;

[0065] The above is only a preferred specific implementation method, but the protection scope is not limited to it. Any technician familiar with this technical field can make equivalent substitutions or changes based on the technical solutions and inventive concepts within the disclosed technical scope, which should be covered by the protection scope.

Claims

1. A brushless motor with an axial bearing structure, comprising: A shell (100); a shell cover (200) connected to one end of the shell (100) and forming a first inner space between the shell cover and the shell (100); A stator (300) is arranged in the first inner space; a rotor (400), a part of which is disposed in the first inner space and surrounded by the stator (300), and the other part of which passes through the housing (100); and two bearings (500), one of which is connected to the housing (100) and the other of which is connected to the housing cover (200), for supporting the rotor (400); The rotor (400) comprises: a rotating shaft (401), which is arranged in the first inner space and has one end extending through the housing (100), and the rotating shaft (401) is supported by the bearing (500); a rotor core (402), which is arranged in the first inner space and connected to the rotating shaft (401); and a magnetic steel (403), which is arranged in the first inner space and connected to the rotor core (402); The invention is characterized in that it further comprises: an elastic support (10) arranged in the first inner space, connected between the housing (100), the stator (300), the rotor (400) and one of the bearings (500), and used to support one of the bearings (500); and a rigid support (20) arranged at a distance from the elastic support (10), wherein the rigid support (20) is arranged in the first inner space, one end of the rigid support (20) is connected between the housing cover (200) and another of the bearings (500), and the other end protrudes from the housing cover (200), and used to support another of the bearings (500).

2. The brushless motor with an axial bearing structure according to claim 1, characterized in that: The elastic support (10) comprises: a first part, arranged in the first inner space, arranged between the housing (100), the rotor (400) and the bearing (500); and a second part, arranged between the first part, the rotating shaft (401) and the bearing (500), and used for elastically supporting the bearing (500).

3. The brushless motor with an axial bearing structure according to claim 2, characterized in that: The first part comprises: a first support (11), which is arranged in the first inner space, contacts the housing (100), and surrounds the rotating shaft (401) at its middle portion, and is spaced apart from the rotating shaft (401); and a first stopper (12), which is connected to the rotating shaft (401) and is arranged between the rotor core (402) and the first support (11), and a first gap (13) is provided between the first stopper (12) and the first support (11).

4. The brushless motor with an axial bearing structure according to claim 3, characterized in that: The second part is a first elastic member (14), and the first elastic member (14) is arranged between the first support (11), the rotating shaft (401), the bearing (500) and the first stopper (12), and is used for elastically supporting the bearing (500).

5. The brushless motor with an axial bearing structure according to claim 4, characterized in that: The first elastic member (14) is a cylindrical spring.

6. The brushless motor with an axial bearing structure according to claim 1, characterized in that: The elastic support (10) comprises: a third part, arranged in the first inner space, arranged between the housing (100), the rotor (400) and the bearing (500); and a fourth part, arranged between the housing (100), the rotating shaft (401) and the bearing (500), and used for elastically supporting the bearing (500).

7. The brushless motor with an axial bearing structure according to claim 6, characterized in that: The third part comprises: a second support (10-1), which is arranged in the first inner space, contacts the housing (100), surrounds the rotating shaft (401) at its middle portion, and is spaced apart from the rotating shaft (401); and a second stopper (10-2), which is connected to the rotating shaft (401), is arranged between the rotor core (402) and the bearing (500), is partially surrounded by the middle portion of the second support (10-1), and has a second gap (10-3) between the second stopper (10-2) and the second support (10-1).

8. The brushless motor with an axial bearing structure according to claim 7, characterized in that: The fourth part is a second elastic member (10-4), which is arranged between the housing (100), the rotating shaft (401) and the bearing (500), and is spaced apart from the second stop member (10-2), and is used to elastically support the bearing (500).

9. The brushless motor with an axial bearing structure according to claim 8, characterized in that: The second elastic member (10-4) is a corrugated gasket.

10. A brushless motor with an axial bearing structure according to claim 5 or 9, characterized in that: The rigid support (20) comprises: a third support (21), one end of which is connected between the shell cover (200) and another of the bearings (500), and the other end of which protrudes from the shell cover (200), and a second inner space (22) is defined between the third support (21), the rotating shaft (401) and the bearing (500); and a pressure-bearing member (23) disposed in the second inner space (22), and the pressure-bearing member (23) contacts the rotating shaft (401) and the third support (21).

11. The brushless motor with an axial bearing structure according to claim 10, characterized in that: The pressure-bearing member (23) is a steel ball.

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