CN114552850A

CN114552850A - Pre-tightening structure and motor

Info

Publication number: CN114552850A
Application number: CN202210104320.6A
Authority: CN
Inventors: 廖然; 郭佳杰
Original assignee: Shenzhen Ruyuan Technology Co ltd
Current assignee: Shenzhen Ruyuan Technology Co ltd
Priority date: 2022-01-28
Filing date: 2022-01-28
Publication date: 2022-05-27

Abstract

The application provides a pretension structure and motor. The pre-tightening structure comprises at least one abutting part and an elastic part. The abutting part abuts against the outer ring of the bearing. The elastic part provides pre-tightening force for the abutting part; the abutting part uniformly disperses the pretightening force to the end face of the outer ring. In the pretension structure and the motor of this application, elasticity portion and butt portion are connected, butt portion and the outer lane butt of bearing, and when elasticity portion provided the pretightning force to butt portion, butt portion can be with the terminal surface of pretightning force homodisperse to the outer lane for wearing and tearing department between the ball of bearing and the inner circle of outer lane, ball and bearing is in the even state of atress in each position, can avoid local excessive wearing and tearing to lead to the phenomenon that noise and vibration appear in advance in the design life of bearing, make the operation that the motor can be stable for a long time.

Description

Pre-tightening structure and motor

Technical Field

The application relates to the technical field of motors, in particular to a pre-tightening structure and a motor.

Background

The small-sized super-high-speed motor is a motor with the rotating speed of tens of thousands or even more than one hundred thousands of revolutions per minute, and is widely applied to equipment such as a dust collector, an electric hair drier, a hand dryer, a sweeper and the like. In a small ultra high speed motor, in order to ensure smooth rotation, the rotating shaft needs at least two bearings for support, in which an inner ring is fixed with the rotating shaft and an outer ring is fixed to a bearing sleeve or a stator housing.

In the operation process of the small-sized super-high speed motor, due to the characteristic of high rotating speed, the small-sized super-high speed motor is extremely sensitive to small gaps, the negative influence caused by the gaps generated by bearing abrasion is amplified, particularly, the rotating number of turns of a rotating shaft of the small-sized super-high speed motor is far more than that of a common motor in the same operation time, and the sensitivity degree to vibration and noise is higher, so that the bearing structure capable of adapting to the common motor is difficult to operate stably in the small-sized super-high speed motor for a long time, and the problem that the normal service life of the small-sized super-high speed motor is disturbed is caused.

Disclosure of Invention

The embodiment of the application provides a pretensioning structure and a motor, which are at least used for solving the problems of noise and vibration in advance when a bearing runs.

The pretensioning structure according to the embodiment of the present application includes at least one abutting portion and an elastic portion. The abutting part abuts against an outer ring of the bearing. The elastic part provides pre-tightening force for the abutting part; the abutting part uniformly disperses the pretightening force to the end face of the outer ring.

The motor of this application embodiment includes casing, pivot, bearing and this application embodiment's pretension structure. The rotating shaft is rotatably mounted on the shell. The bearing comprises an inner ring arranged on the rotating shaft and an outer ring arranged on the shell. The abutting part abuts against the outer ring.

In the pretension structure and the motor of this application, elasticity portion and butt portion are connected, butt portion and the outer lane butt of bearing, and when elasticity portion provided the pretightning force to butt portion, butt portion can be with the terminal surface of pretightning force homodisperse to the outer lane for wearing and tearing department between the ball of bearing and the inner circle of outer lane, ball and bearing is in the even state of atress in each position, can avoid local excessive wearing and tearing to lead to the phenomenon that noise and vibration appear in advance in the design life of bearing, make the operation that the motor can be stable for a long time.

Additional aspects and advantages of embodiments of the present application will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of embodiments of the present application.

Drawings

The above and/or additional aspects and advantages of the present application will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a schematic structural view of a pretensioning structure according to certain embodiments of the present application;

FIG. 2 is a schematic view of the pre-tensioning arrangement of FIG. 1 engaged with a bearing;

FIG. 3 is a schematic structural view of a bearing-mounted coil spring;

FIG. 4 is a schematic structural view of a ring structure according to certain embodiments of the present application;

FIG. 5 is a schematic structural view of a ring structure according to certain embodiments of the present application;

FIG. 6 is a schematic structural view of an abutment according to certain embodiments of the present application including a cylindrical structure;

FIG. 7 is a schematic illustration of the structure of certain embodiments of the present application in which a bearing is mated to a cylindrical structure;

FIG. 8 is a schematic view of a bearing of certain embodiments of the present application in cooperation with two cylindrical structures;

FIG. 9 is a schematic structural view of an abutment according to certain embodiments of the present application including a circular configuration;

FIG. 10 is a schematic view of the inner and outer sleeves of certain embodiments of the present application in combination with a bearing;

FIG. 11 is a schematic structural view of an electric machine according to certain embodiments of the present application;

fig. 12 is a schematic diagram of the structure of a pretensioning structure according to certain embodiments of the present application.

Detailed Description

Embodiments of the present application will be further described below with reference to the accompanying drawings. The same or similar reference numbers in the drawings identify the same or similar elements or elements having the same or similar functionality throughout.

In addition, the embodiments of the present application described below in conjunction with the accompanying drawings are exemplary and are only for the purpose of explaining the embodiments of the present application, and are not to be construed as limiting the present application.

In this application, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through intervening media. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

Referring to fig. 1 and 2, the present application provides a pretensioning structure 10. The pretensioning structure 10 includes at least one abutting portion 11 and an elastic portion 13. The contact portion 11 contacts the outer ring 31 of the bearing 30. The elastic portion 13 provides a pre-tightening force to the abutting portion 11, and the abutting portion 11 uniformly disperses the pre-tightening force to the end face of the outer ring 31.

As shown in fig. 3, when a normal spring (coil spring) is installed in the bearing, the spring in the I portion of the end portion of the normal spring abuts against the outer race of the bearing, the spring in the part II in the end part of the common spring is not contacted with the bearing, namely, the actual load born by the bearing end surface which is abutted against the part I is larger, the pretightening force born by the bearing end surface corresponding to the part II indirectly comes from the part I, thereby causing the bearing end face abutted by the part I to be stressed greatly, the bearing end face corresponding to the part II to be stressed less, the friction between the balls in the bearing corresponding to the part I and the bearing outer ring is large, the abrasion is serious, the friction between the ball inside the bearing and the outer ring of the bearing at the part I is small, the abrasion is small, after a period of time, the degree of abrasion of the bearing outer ring is uneven, and the problems of vibration, noise and the like are caused.

In the pretensioning structure 10 of the present application, the elastic portion 13 is connected to the abutting portion 11, the abutting portion 11 abuts against the outer ring 31 of the bearing 30, and when the elastic portion 13 provides the pretensioning force to the abutting portion 11, the abutting portion 11 can uniformly disperse the pretensioning force to the end surface of the outer ring 31, so that the abrasion between the balls (not shown) of the bearing 30 and the outer ring 31 and between the balls and the inner ring 33 of the bearing 30 are in a state of uniform stress at each position, a phenomenon that noise and vibration occur in advance in the design life due to local excessive abrasion can be avoided, and the motor 100 (shown in fig. 11) can operate stably for a long time.

The pretensioning structure 10 will be described in detail below with reference to the accompanying drawings.

In one embodiment, the abutment portion 11 and the resilient portion 13 are of unitary construction, as shown in fig. 1. Thus, the pre-tightening structure 10 is simple in structure and convenient to install.

In another embodiment, the abutting portion 11 and the elastic portion 13 are of a separate structure. For example, as shown in fig. 4, the abutting portion 11 has an annular structure, the abutting portion 11 abuts against the outer race 31, the elastic portion 13 is a normal spring, and the elastic portion 13 is connected to the abutting portion 11 by welding, gluing, or the like. For example, as shown in fig. 5, the abutting portion 11 and the elastic portion 13 are fixedly connected to each other by welding, gluing, or the like to be fixed to each other, thereby forming the pretensioned structure 10 as a whole. The elastic portion 13 is connected with the abutting portion 11, when the elastic portion 13 is elastically deformed, a pre-tightening force can be provided for the abutting portion 11, and the abutting portion 11 uniformly disperses the pre-tightening force to the end face of the outer ring 31.

Referring to fig. 12, in some embodiments, the pre-tightening structure 10 includes a specially optimized spring, which is further optimized for a common spring, and an end portion of the spring constitutes the abutting portion 11, which is different from a common helical spring in that an end surface of the abutting portion 11 facing the outer ring 31 is a ring-shaped surface with a constant width, while a conventional common spring is formed by spirally winding a cylindrical wire, and an abutting surface of the conventional common spring is a cylindrical outer side surface, after installation, due to problems such as assembly accuracy, the outer ring 31 itself is a plane, and mutual abutting between the plane and the cylindrical surface actually forms line contact, which may cause uneven distribution of the pre-tightening force according to a difference in contact position. After the annular surface with the unchanged width is used as the abutting surface, even if assembly errors exist to cause that all parts of the outer ring 31 abut on different positions of the annular surface, surface contact is still formed, the problem of non-uniform pretightening force is avoided, and the pretightening force is uniformly dispersed to the end surface of the outer ring 31. More specifically, the pretensioning structure 10 in this embodiment, in the axial direction, has a middle portion constituting the elastic portion 13, which can be set to have a large deformation space/stroke for achieving pretensioning by compression, and both ends each constituting the abutment portion 11, which is set to have a small deformation space/stroke for uniformly transmitting the pretensioning force to the abutment surface. More specifically, the pre-tightening structure 10 may be formed by spirally winding a wire rod with a rectangular cross section, each axial surface of the wire rod forms the annular surface with the constant width, and in order to increase the area of the abutting surface and reduce the pressure, the wire rod itself may be flat, that is, in the rectangular cross section of the wire rod, the side length parallel to the axis of the pre-tightening structure 10 is shorter, and the other side length is longer. It is to be understood that the coil springs and the ordinary springs in the foregoing and the following may also be referred to as the springs in the present embodiment, i.e., the springs in the present embodiment may also be part of other embodiments, and together with other related structures, form the pre-tightening structure 10, unless otherwise specified.

Referring to fig. 1, the pretensioning structure 10 includes an annular structure 12, the annular structure 12 includes a sub-ring 121, the sub-ring 121 has a plurality of protrusions 1211 and recesses 1213 alternately arranged, and the protrusions 1211 forms an abutting portion 11 and abuts against the outer ring 31.

The ring structure 12 has one or more layers, each layer forming a sub-ring 121. The arcs of the projections 1211 and the recesses 1213 in the sub-ring 121 on the same layer are the same, so that the loads applied to the plurality of projections 1211 and the recesses 1213 on the same layer are the same, and the loads applied to the outer ring 31 by the projections 1211 when the outermost projections 1211 abuts against the outer ring 31 of the bearing 30 are the same.

The sub-ring 121 is annular, and the sub-ring 121 may be formed by molding a metal sheet. The end face of the sub-ring 121 has uniform undulations in the circumferential direction. In one embodiment, when the bearing 30 is mounted on the left side of the ring structure 12, the portion of the sub-ring 121 that faces the left in fig. 2 forms a protrusion 1211, and the portion of the sub-ring 121 that faces the right in fig. 2 forms a recess 1213, as shown in fig. 2. In another embodiment, when the bearing 30 is mounted on the right side of the ring structure 12, the portion of the sub-ring 121 that faces the left in fig. 2 forms the recess 1213, and the portion of the sub-ring 121 that faces the right in fig. 2 forms the projection 1211. The ring structure 12 will be described in detail with reference to the example that the end surface of the sub-ring 121 is protruded toward the left to form the protrusion 1211 and protruded toward the right to form the depression 1213.

Referring to fig. 1 and 2, in some embodiments, the sub-ring 121 is an elastic structure, the annular structure 12 includes a plurality of sub-rings 121 stacked and abutted in sequence, and the outermost protrusion 1211 forms the abutting portion 11 and abuts against the outer ring 31 of the bearing 30 mounted on the left side.

In particular, the number of bearings 30 may comprise two, the annular structure 12 being mounted between two bearings 30. The ring structure 12 includes opposing first and second ends 123 and 125. The protruding portion 1211 located on the outermost side of the first end 123 and the recessed portion 1213 located on the outermost side of the second end 125 form the abutting portion 11. The projection 1211 located outermost at the first end 123 abuts the outer ring 31 of one of the bearings 30 (the left bearing 20 in fig. 2), and the recess 1213 located outermost at the second end 125 abuts the outer ring 31 of the other bearing 30 (the right bearing 20 in fig. 2).

The sub-rings 121 located between the first end 123 and the second end 125 form an elastic structure, the sub-rings 121 are integrally formed, the elastic structure forms the elastic portion 13, the elastic portion 13 can provide uniform pretightening force for the abutting portions 11 of the first end 123 and the second end 125, so that the outer rings 31 of the two bearings 30 at the two ends all receive uniform pretightening force, and the phenomenon that the bearings 30 generate noise and vibration in advance in the design life due to local excessive abrasion of the bearings 30 is avoided.

The elastic portion 13 includes a coil spring (a normal spring as shown in fig. 3) abutting one side of the sub-ring 121, and the other side of the sub-ring 121 abuts the outer race 31.

Referring to fig. 4, in some embodiments, the number of the sub-rings 121 is one, that is, the ring structure 12 is composed of a layer of sub-rings 121. The projection 1211 on the sub-ring 121 abuts against the outer ring 31 of the bearing 30.

Referring to fig. 2, specifically, when the number of the bearings 30 is two, the number of the ring structures 12 is also two, and two ends of the coil spring respectively abut against the two ring structures 12. The outer ring 31 of one of the bearings 30 abuts against the projection 1211, and the outer ring 31 of the other bearing 30 abuts against the recess 1213. Alternatively, the outer rings 31 of both the bearings 30 abut against the projection 1211. When the helical spring provides pretightening force to the sub-rings 121 on the two sides, the pretightening force is uniformly dispersed to the outer rings 31 of the bearings 30 on the two sides by the sub-rings 121 on the two sides, so that the abrasion parts between the balls of the bearings 30 on the two sides and the outer rings 31 of the bearings and between the balls and the inner rings 33 of the bearings 30 are in a state of uniform stress at all positions, and the phenomenon that the bearings 30 generate noise and vibration in advance in the design life due to local excessive abrasion can be avoided.

Referring to fig. 5, in some embodiments, the ring structure 12 includes a plurality of ring structures 12, each ring structure 12 is composed of a sub-ring 121, the ring structures 12 are stacked, the protruding portion 1211 of each ring structure 12 is connected to the recessed portion 1213 of the adjacent ring structure 12, the ring structures 12 form the elastic portion 13, and the outermost protruding portion 1211 forms the abutting portion 11.

Specifically, the prefastening structure 10 includes opposing first and

second sides

14 and 15. The protrusion 1211 located on the first side 14 and/or the recess 1213 located on the second side 15 form the abutment 11. For example, when the number of the bearings 30 is one, the projection 1211 located on the first side 14 forms the abutment portion 11 and abuts against the outer ring 31 of the bearing 30. Alternatively, the recessed portion 1213 on the second side 15 forms the abutment portion 11 and abuts against the outer ring 31 of the bearing 30. Also for example, when the number of the bearings 30 is two, the convex portion 1211 located on the first side 14 and the concave portion 1213 located on the second side 15 collectively form the abutment portion 11, and the abutment portions 11 on both sides abut against the outer rings 31 of the two bearings 30, respectively.

In one embodiment, the number of the ring structures 12 is three, as shown in fig. 5, the recessed portion 1213 of the ring structure 12 on the first side 14 abuts against the protruding portion 1211 of the middle ring structure 12, the recessed portion 1213 of the middle ring structure 12 abuts against the protruding portion 1211 of the ring structure 12 on the second side 15, and the abutting portions of the recessed portion 1213 and the protruding portion 1211 can be fixed by welding, gluing or the like, so that the three ring structures 12 are formed with the elastic portions 13, and the misalignment of the ring structures 12 when rotating is prevented from becoming an overlapped loading state.

Referring to fig. 6 and 7, in some embodiments, the abutting portion 11 includes a cylindrical structure 111, the cylindrical structure 111 includes a bottom 1111 and a sidewall 1113 extending from the bottom 1111 in an axial direction, the sidewall 1113 of the cylindrical structure 111 has an annular end surface 11131, and the annular end surface 11131 forms the abutting portion 11 and abuts against the outer ring 31. The elastic portion 13 abuts to the bottom 1111 of the cylindrical structure 111.

Specifically, the side wall 1113 of the cylindrical structure 111 extends in the axial direction from one side of the bottom 1111, and the other side of the bottom 1111 abuts against the elastic portion 13. The annular end surface 11131 is a flat end surface, the annular end surface 11131 is integrally attached to and abutted against the outer ring 31, the pretightening force provided by the elastic part 13 sequentially passes through the bottom 1111 and the side wall 1113 of the cylindrical structure 111, and the pretightening force is uniformly dispersed to the outer ring 31 by the annular end surface 11131.

In one embodiment, the cylindrical structure 111 comprises one, the elastic portion 13 being constituted by one or more annular structures 12. In the case where the elastic portion 13 is composed of one ring structure 12, the ring structure 12 includes a plurality of sub-rings 121 which are stacked and abutted, as shown in fig. 1. In the case where the elastic portion 13 is composed of a plurality of ring structures 12, each ring structure 12 is composed of one sub-ring 121, as shown in fig. 5.

When the number of the bearings 30 includes two, the outer ring 31 of one of the bearings 30 abuts against the annular end surface 11131, the outer ring 31 of the other bearing 30 may abut against the projection 1211 (at this time, the projection 1211 forms the abutting portion 11) of the annular structure 12, and the recess 1213 of the annular structure 12 abuts against the bottom 1111; alternatively, the outer ring 31 of one of the bearings 30 may abut the annular end surface 11131, the outer ring 31 of the other bearing 30 may abut the recessed portion 1213 of the annular structure 12 (at this time, the recessed portion 1213 forms the abutting portion 11), and the protruding portion 1211 of the annular structure 12 may abut the bottom portion 1111. In this way, the preload provided by the elastic portion 13 can be uniformly dispersed to the outer rings 31 of the two bearings 30 through the annular end surface 11131 and the protruding portion 1211.

In some embodiments, the elastic portion 13 may include a coil spring. When the number of the bearings 30 is one, the annular end surface 11131 entirely abuts against the outer race 31 of the bearing 30, one end of the elastic portion 13 abuts against the bottom 1111 of the cylindrical structure 111, and the other end is fixed to another structure. When the number of the bearings 30 is two, the abutting portion 11 includes the cylindrical structure 111 and the annular structure 12 (as shown in fig. 4), and at this time, the annular structure 12 is one, the annular end surface 11131 is entirely abutted and abutted against the outer ring 31 of one of the bearings 30, the projection 1211 or the recess 1213 of the annular structure 12 is abutted against the outer ring 31 of the other bearing 30, one end of the elastic portion 13 is abutted against the bottom 1111 of the cylindrical structure 111, and the other end of the elastic portion 13 is abutted against the annular structure 12. In this way, the elastic portion 13 can provide a pre-tightening force to the outer rings 31 of the bearings 30 on both sides, and the pre-tightening force is uniformly distributed to the outer rings 31 of the bearings 30 on both sides through the annular end surface 11131 and the protruding portion 1121 (or the recessed portion 1213), so that the bearings 30 on both sides do not generate noise and vibration in advance in the design life.

Referring to fig. 8, in another embodiment, the cylindrical structures 111 include at least two cylindrical structures 111, the two cylindrical structures 111 are symmetrically disposed, and the elastic portion 13 is located between the two cylindrical structures 111. At this time, the number of the bearings 30 may include one or two, and when the number of the bearings 30 is one, one of the cylindrical structures 111 abuts to the outer race 31 of the bearing 30, the other cylindrical structure 111 abuts to the other structure, and both ends of the elastic portion 13 abut to the bottoms 1111 of the two cylindrical structures 111, respectively. When the number of the bearings 30 is two, one of the cylindrical structures 111 abuts to the outer ring 31 of one of the bearings 30, and the other cylindrical structure 111 abuts to the outer ring 31 of the other bearing 30. The cylindrical structure 111 will be described below with the number of bearings 30 being two. Wherein the elastic portion 13 may comprise an elastic structure formed by a coil spring and a ring structure 12 (as shown in fig. 1 and 5).

The number of cylindrical structures 111 may include two, three, or more than three. For example, when the number of the cylindrical structures 111 is two, the annular end surfaces 11131 of the two cylindrical structures 111 abut the outer races 31 of the two bearings 30, respectively, and the elastic portion 13 is located between the bottoms 1111 of the two cylindrical structures 111. Also for example, when the number of the cylindrical structures 111 is three, the two cylindrical structures 111 on both sides abut the outer rings 31 of the two bearings 30, respectively, and the elastic portion 13 is located between the cylindrical structure 111 on one side and the cylindrical structure 111 in the middle. Wherein the annular end surface 11131 of the middle cylindrical structure 111 abuts against the bottom 1111 of the one-side cylindrical structure 111, the two ends of the elastic part 13 abut against the bottom 1111 of the middle cylindrical structure 111 and the bottom 1111 of the one-side cylindrical structure 111, respectively, and the middle cylindrical structure 111 and the two bearings 30 are not in contact with each other. In this way, the elastic portion 13 pushes the cylindrical structures 111 on both sides to move in opposite directions to apply a preload to the outer rings 31 of the bearings 30 on both sides.

Referring to fig. 9, in some embodiments, the abutting portion 11 may include a circular structure 113, the circular structure 113 includes a plurality of protrusions 1131, the plurality of protrusions 1131 are uniformly distributed on a periphery of an end surface 1133 of the circular structure 113, and the plurality of protrusions 1131 form the abutting portion 11 and abut against the outer ring 31 (shown in fig. 8).

Specifically, a through hole 1135 is formed in the middle of the circular structure 113, so that the rotating shaft 50 can pass through the through hole and is rotatably connected with the bearing 30. The protrusions 1131 are distributed on one side of the circular structure 113, and the other side of the circular structure 113 abuts against the elastic portion 13. When the elastic portion 13 provides a pre-tightening force to the circular structure 113, the pre-tightening force is uniformly dispersed to the outer ring 31 through the plurality of protrusions 1131 uniformly distributed on the periphery of the circular structure 113, so that the pre-tightening force applied to each abutting part of the outer ring 31 is the same.

Referring to fig. 8, in some embodiments, the elastic portion 13 includes a plurality of belleville springs (not shown) which are abutted in sequence, and the end surfaces of the outermost belleville springs constitute the abutting portion 11. The load on the end face of the belleville spring is the same everywhere, and when the end face of the belleville spring is abutted to the outer ring 31, the pretightening force provided by the belleville spring can be uniformly dispersed to the outer ring 31. A plurality of belleville springs may achieve a greater amount of deflection and provide a lower load to accommodate a smaller size bearing 30.

Referring to fig. 10, in some embodiments, the abutting portion 11 includes an inner sleeve 115, the number of the bearings 30 is two, and two ends of the inner sleeve 115 abut against the two bearings 30 respectively; the pretensioning structure 10 may further include an outer sleeve 17, the outer sleeve 17 receives the inner sleeve 115 and the bearing 30, two ends of the outer sleeve 17 are each formed with a protrusion 171 protruding inward, one protrusion 171 abuts against the corresponding outer ring 31, and the elastic portion 13 is installed between the other protrusion 171 and the corresponding outer ring 31. The projections 171 at both ends restrict the axial displacement of the outer ring 31.

Specifically, one end of the elastic portion 13 abuts against the outer ring 31 of the right bearing 30, and the other end of the elastic portion 13 abuts against one of the protrusions 171 of the outer sleeve 17, so that when the elastic portion 13 provides a biasing force, the elastic portion 13 provides a leftward force to the outer ring 31 of the right bearing 30, the inner sleeve 115 abuts against the outer rings 31 of the two bearings 30, and the outer ring 31 of the right bearing 30 does not slide in the opposite direction with respect to the balls of the bearings 30. The elastic portion 13 applies a rightward force to the right-side projection 171, the left-side projection 171 applies a rightward force to the outer ring 31 of the left-side bearing 30, and the outer ring 31 of the left-side bearing 30 does not slide in the opposite direction with respect to the balls of the bearing 30. Therefore, the abrasion parts between the balls of the bearing 30 and the outer ring 31 and between the balls and the inner ring 33 of the bearing 30 are in a state of uniform stress at each position, and the phenomenon that the bearing 30 generates noise and vibration in advance in the design life due to local excessive abrasion can be avoided. Meanwhile, the stroke of the elastic part 13 needing to be compressed is effectively reduced, so that the elastic part 13 provides a required pre-tightening force in a smaller stroke, and the elastic part is suitable for elastic structures with larger strength coefficients, for example, the elastic part 13 is an elastic structure formed by the annular structure 12 shown in fig. 1 and 5 and a belleville spring.

Referring to fig. 10 and 11, in some embodiments, the abutting portion 11 includes an inner sleeve 115, the number of the bearings 30 is two, and two ends of the inner sleeve 115 abut against the two bearings 30 respectively; the pretensioning structure 10 can also comprise a housing 70. The inner sleeve 115 and the bearing 30 are placed in the housing 70, and the side wall of the housing 70 is formed with a projection 171 protruding inward, wherein one projection 171 abuts against the corresponding outer ring 31, and the elastic portion 13 is installed between the other projection 171 and the corresponding outer ring 31.

In particular, the outer sleeve 17 in the above embodiment may be a part of the housing 70, so that the assembly connection between the components of the pretensioning structure 10 can be reduced, resulting in a simple structure of the pretensioning structure 10.

It should be noted that the elastic portion 13 installed between the projection 171 and the corresponding outer ring 31 may include an elastic structure formed by a coil spring and the ring structure 12 (as shown in fig. 1 and 5). The abutting portion 11 formed by the inner sleeve 115 can be used for abutting the split bearing 30, and the application range is wide.

It should be noted that the above embodiments can be combined without contradiction, for example, the coil spring, the inner sleeve 115 and the annular structure 12; also for example, the annular structure 12, the inner sleeve 115 and the outer sleeve 17; also for example, the ring structure 12 and the cylindrical structure 111; as another example, the loop structure 12 and the belleville springs.

Referring to fig. 11, the present application further provides a motor 100. The motor 100 includes the preloading structure 10, the bearing 30, the rotating shaft 50 and the housing 70 according to any embodiment of the present application. The shaft 50 is rotatably mounted to the housing 70. The bearing 30 includes an inner race 33 mounted to the rotating shaft 50 and an outer race 31 mounted to the housing 70. The abutting portion 11 of the pre-tightening structure 10 abuts against the outer ring 31, the elastic portion 13 of the pre-tightening structure 10 provides pre-tightening force for the abutting portion 11, and the abutting portion 11 uniformly disperses the pre-tightening force to the end face of the outer ring 31, so that the abrasion between the balls of the bearing 30 and the outer ring 31 and between the balls and the inner ring 33 of the bearing 30 are in a state of uniform stress at each position, and the phenomenon that noise and vibration occur in advance in the design life due to local excessive abrasion can be avoided.

The motor 100 may comprise a small ultra-high speed motor suitable for use in a vacuum cleaner, hair dryer, hand dryer, sweeper, etc.

The number of the bearings 30 is two, and the pre-tightening structure 10 is positioned between the two bearings 30; as shown in fig. 2, 7, 8; or on the outside of either bearing 30 away from the other bearing 30, as shown in fig. 10.

The housing 70 is provided with a mounting hole 71, and the rotating shaft 50 is matched with the mounting hole 71 to be mounted on the housing 70, so that the rotating shaft 30 can rotate in the mounting hole 71.

Referring to fig. 10, in some embodiments, the sidewall 711 of the mounting hole 71 forms an outer sleeve 17, the outer sleeve 17 receives the bearing 30, two ends of the outer sleeve 17 protrude inward (toward the rotating shaft 50) to form a protrusion 171, one of the protrusions 171 abuts against the corresponding outer ring 31, and the elastic portion 13 is mounted between the other protrusion 171 and the corresponding outer ring 31.

The motor 100 may also include a magnet 60 and a blade 90. The magnets 60 are installed at one end of the rotating shaft 50, wherein one bearing 30 is positioned between the other bearing 30 and the magnets 60; or the magnet 60 is installed at the middle of the rotating shaft 50, and the magnet 60 is located between the two bearings 30. The vane 90 is mounted to one end of the rotary shaft 50.

In one embodiment, the blade 90 is mounted to the left end of the shaft 50 and the magnet 60 is mounted to the end of the shaft 50 adjacent to the blade 90, with one bearing 30 located between the other bearing 30 and the magnet 60. Alternatively, the blade 90 is mounted on the left end of the rotating shaft 50, and the magnet 60 is mounted on the end of the rotating shaft 50 away from the blade 90, wherein one of the bearings 30 is located between the other bearing 30 and the magnet 60.

In another embodiment, the magnet 60 is installed at the middle of the rotating shaft 50, and one bearing 30 is provided at each end of the rotating shaft 50.

The portion of the housing 70 corresponding to the magnet 60 is provided with a winding 80, the winding 80 cooperates with the magnet 60, and the magnetic field generated by the magnet 60 interacts with the magnetic field generated by the winding 80 to generate a force, so as to drive the rotating shaft 50 to rotate, and thus the inner ring 33 of the bearing 30 to rotate.

In the pretensioning structure 10 and the motor 100 of the present application, the elastic portion 13 is connected to the abutting portion 11, the abutting portion 11 abuts against the outer ring 31 of the bearing 30, and when the elastic portion 13 provides the pretensioning force to the abutting portion 11, the abutting portion 11 can uniformly disperse the pretensioning force to the end surface of the outer ring 31, so that the abrasion between the balls (not shown) of the bearing 30 and the outer ring 31 and between the balls and the inner ring 33 of the bearing 30 are in a state of uniform stress at each position, and the phenomenon that noise and vibration occur in advance in the design life due to local excessive abrasion can be avoided, so that the small-sized ultra-high-speed motor can operate stably for a long time.

In the description herein, reference to the description of the terms "certain embodiments," "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the feature. In the description of the present application, "a plurality" means at least two, e.g., two, three, unless specifically limited otherwise.

Although embodiments of the present application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present application, and that variations, modifications, substitutions and alterations of the above embodiments may be made by those of ordinary skill in the art within the scope of the present application, which is defined by the claims and their equivalents.

Claims

1. A pretensioning structure, comprising:

at least one abutting portion abutting against an outer ring of the bearing; and

an elastic portion that provides a preload to the abutting portion;

the abutting part uniformly disperses the pretightening force to the end face of the outer ring.

2. The pretensioning structure according to claim 1, wherein the abutting portion and the elastic portion are of an integral structure; or

The abutting part and the elastic part are of a split structure.

3. The pretensioning structure of claim 1, comprising an annular structure comprising a sub-ring having a plurality of alternately arranged projections and recesses, the projections constituting the abutment and abutting the outer ring.

4. The pretensioning structure of claim 3, wherein the resilient portion comprises a coil spring abutting one side of the sub-ring and the other side of the sub-ring abutting the outer race.

5. The pretensioning structure according to claim 3, wherein the sub-ring is an elastic structure, the annular structure comprises a plurality of sub-rings which are stacked and abutted in sequence, and the outermost protruding portion forms the abutting portion and abuts against the outer ring.

6. The pretensioning structure according to claim 3, wherein the ring-shaped structure comprises a plurality of ring-shaped structures, each ring-shaped structure is composed of one sub-ring, the plurality of ring-shaped structures are stacked, the protruding portion of each ring-shaped structure is connected with the recessed portion of the adjacent ring-shaped structure, the plurality of ring-shaped structures form the elastic portion, and the protruding portion on the outermost side forms the abutting portion and abuts against the outer ring.

7. The pretensioning structure of claim 1, wherein the abutment portion comprises a cylindrical structure including a bottom portion and a side wall extending from the bottom portion in an axial direction, the side wall having an annular end surface that constitutes the abutment portion and abuts against the outer ring.

8. The pretensioning structure of claim 7, wherein the resilient portion abuts the bottom of the cylindrical structure, the resilient portion comprising a coil spring.

9. The pretensioning structure according to claim 1, wherein the abutting portion comprises a circular structure, the circular structure comprises a plurality of protrusions, the protrusions are uniformly distributed on the periphery of the end face of the circular structure, and the protrusions form the abutting portion and abut against the outer ring.

10. The pretensioning structure according to claim 1, wherein the elastic portion includes a plurality of disc springs that abut one another in sequence, and end surfaces of the outermost disc springs constitute the abutting portion.

11. The pretensioning structure according to claim 1, wherein the abutting portion comprises an inner sleeve, the number of the bearings is two, and two ends of the inner sleeve abut against the two bearings respectively;

the pre-tightening structure further comprises an outer sleeve, the outer sleeve accommodates the inner sleeve and the bearing, two ends of the outer sleeve are both inwards protruded to form protruding blocks, one protruding block is abutted to the corresponding outer ring, and the elastic part is arranged between the other protruding block and the corresponding outer ring.

12. The pretensioning structure according to claim 1, wherein the abutting portion comprises an inner sleeve, the number of the bearings is two, and two ends of the inner sleeve abut against the two bearings respectively;

the pretension structure further comprises a shell, the inner sleeve and the bearing are arranged in the shell, the side wall of the shell is inwards protruded to form a protruding block, one protruding block is abutted to the corresponding outer ring, and the elastic part is arranged between the other protruding block and the corresponding outer ring.

13. An electric machine, comprising:

a housing;

the rotating shaft is rotatably arranged on the shell;

the bearing comprises an inner ring arranged on the rotating shaft and an outer ring arranged on the shell; and

the pretensioning structure of any one of claims 1 to 12, wherein said abutment abuts said outer ring.

14. The electric motor of claim 13, wherein the housing is provided with a mounting hole, and the shaft is engaged with the mounting hole to be mounted to the housing.

15. The electric machine of claim 13, wherein the number of bearings is two, and the pre-tensioning arrangement is located between the two bearings or on the outside of either bearing away from the other bearing.