Pre-tightening structure of motor bearing
By using a pre-tightening structure that connects the inner and outer shaft covers to the outer ring surface of the bearing, and securing it with helical springs and long screws, the problem of accurately controlling the bearing preload in existing technologies is solved. This achieves stable preload in vibrating motors, reducing processing difficulty and cost.
Patent Information
- Application Number
- CN202422930585.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-29
- Publication Date
- 2025-12-23
- Estimated Expiration
- 2034-11-29
AI Technical Summary
In existing technologies, wave springs and disc springs, when in line contact with bearings, are difficult to provide precise preload in motors with large vibrations or large axial dimensions. Furthermore, the manufacturing process is difficult and costly, which can lead to the bearing easily slipping off the outer ring.
The preload structure is adopted, in which the inner and outer shaft covers are in surface contact with the outer ring of the bearing. It is fixed by elastic connecting components and long screws. The inner and outer shaft covers form surface contact with the outer ring of the bearing. The preload force is controlled by the stable elastic coefficient of the helical spring to avoid bearing misalignment and slippage.
It enables stable preload in motors with high vibration or high speed, preventing bearing outer ring slippage, reducing processing difficulty and cost, and is suitable for motors with high precision preload requirements.
Smart Images
Figure CN223713725U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to motor field, concretely relates to a pre -tightening structure of motor bearing. BACKGROUND
[0002] In order to improve the service performance of bearing, improve the service life of bearing, motor bearing generally needs pre -tightening force. Commonly used to add wave spring, disc spring or spiral spring in the bottom of motor bearing chamber, spring is directly contacted with bearing, thereby reaching the effect of exerting pre -tightening force.
[0003] Among them, wave spring is directly acted on bearing, and the contact surface with bearing is the radial line contact formed by several wave crests;Disc spring is directly acted on bearing, and the contact surface with bearing is the line contact of circumference;Spiral spring is directly acted on bearing, and the contact surface with bearing is the line contact of several small circumferences.
[0004] The above-mentioned three kinds of springs are in line contact with bearings, in the occasion of larger vibration, under the influence of vibration acceleration, the wave crest radial or axial deviation of spring may occur, the sliding between spring and bearing is easy, leading to bearing running out of the race.
[0005] In addition, the pre -tightening force applied to bearing by wave spring and disc spring is generally controlled by calculating the working height of motor axial dimension, which is a better choice for the motor with smaller axial dimension and lower axial pre -tightening force requirement. However, for the motor with larger axial dimension, higher axial pre -tightening force requirement or larger vibration, the axial cumulative tolerance is large, the working height of wave spring and disc spring has little adjustable space, and it is difficult to provide axial force accurately. The tightening axial dimension tolerance has limited effect, and greatly increases the processing difficulty and processing cost.
[0006] Therefore, how to solve the above-mentioned problems existing in the prior art has become the subject to be studied and solved by the utility model. CONTENT OF UTILITY MODEL
[0007] The utility model aims at providing a pre -tightening structure of motor bearing.
[0008] In order to achieve the above-mentioned purpose, the utility model adopts the technical scheme that:
[0009] A pre -tightening structure of motor bearing, the bearing is arranged in the bearing chamber of motor end cover, and the inner ring is fixed on the motor rotating shaft through locking device, the pre -tightening structure includes first axle cover and multiple elastic connecting components connecting the first axle cover and the motor end cover;
[0010] The first axle cover is movably sleeved on the motor rotating shaft, and abuts against one end surface of the bearing outer ring under the elastic force of the elastic connecting component.
[0011] The elastic connecting assembly comprises an inner shaft rod and a spring sleeved outside the inner shaft rod;
[0012] The inner shaft rod is screwed with the first shaft cover through a mounting hole on the motor end cover, the mounting hole has a stepped surface, and the end of the inner shaft rod away from the first shaft cover has a first stop surface, and the two ends of the spring abut against the stepped surface and the first stop surface respectively.
[0013] Preferably, the first shaft cover abuts against one end surface of the bearing outer ring through a first boss protruding on the inner end surface, and a gap is reserved between the inner end surface of the first shaft cover outside the first boss and the motor end cover.
[0014] Further preferably, the outer peripheral surface of the first boss is in abutment with the inner wall of the bearing chamber.
[0015] Further preferably, the end of the inner shaft rod close to the first shaft cover has a second stop surface, and the second stop surface abuts against the inner end surface of the first shaft cover.
[0016] Preferably, the pre-tightening structure further comprises a second shaft cover, the second shaft cover is movably sleeved on the motor rotating shaft, and the first shaft cover and the second shaft cover are fixed by a plurality of long screws penetrating through the motor end cover, and the second shaft cover abuts against the other end surface of the bearing outer ring.
[0017] Further preferably, the second shaft cover abuts against the other end surface of the bearing outer ring through a second boss protruding on the end surface, and a gap is reserved between the inner end surface of the second shaft cover outside the second boss and the motor end cover.
[0018] Further preferably, the outer peripheral surface of the second boss is in abutment with the inner wall of the bearing chamber.
[0019] Further preferably, the first shaft cover is arranged on the inner side of the motor end cover, and the second shaft cover is arranged on the outer side of the motor end cover.
[0020] Further preferably, the long screws and the elastic connecting assemblies are arranged alternately and are distributed in a ring array with the shaft center of the motor end cover as the center.
[0021] Further preferably, the long screws and the elastic connecting assemblies are arranged alternately and are distributed in a ring array with the shaft center of the motor end cover as the center.
[0022] The working principle and advantages of the utility model are as follows:
[0023] The utility model discloses a elastic connecting assembly is used to fix the shaft cover in the bearing outer ring, and the shaft cover and the bearing outer ring are surface contact, can increase the friction of bearing outer ring, and the relative stable axial torque is transmitted, thereby obtaining the resistance torque of stable rotating direction, guaranteeing the pre-tightening force of bearing, avoiding the phenomenon that bearing appears to run the outer ring, and being applicable to the occasion of motor application environment vibration is bigger or high -speed operation.
[0024] The utility model discloses a spring is set to the inner shaft rod outside of connecting end cover and shaft cover, and the spring is supported by inner shaft rod radially, thereby can realize axial stable telescoping, avoid deviation, and further guarantee that the shaft cover and bearing outer ring are stable surface contact, avoid bearing to slip and run the outer ring.
[0025] The utility model discloses that elastic connecting assembly sets up 4 or more, can reduce the influence of single elastic connecting assembly state fluctuation to bearing end face pre-tightening force.
[0026] The working stroke of the spring used in the utility model is much larger than that of the wave spring, and the elastic coefficient changes little within the working stroke range of the spring, so that the pre-tightening force of the spring is more easily and accurately controlled by controlling the spacing of the two stop surfaces on the inner shaft rod, and the utility model is applicable to high-speed and super-high-speed motor combinations with high requirements for pre-tightening force.
[0027] The whole pre-tightening structure of the utility model reduces the axial dimension requirement of the end cover and the machine base, can reduce the axial tolerance grade of the motor, and reduces the processing difficulty and processing cost.
[0028] The utility model discloses two inner and outer shaft covers are set up, and the inner and outer shaft covers are directly pulled tightly through long screw, and the both ends of bearing outer ring are axially positioned, under the action of long screw tension, the friction of the contact surface of shaft cover and bearing outer ring can completely avoid circumferential sliding, and the circumferential position between shaft cover and end cover is positioned by long screw, thereby completely avoiding the running circle failure of bearing outer ring. DRAWINGS
[0029] ATTACH Figure 1 It is the overall sectional view of the utility model embodiment 1;
[0030] ATTACH Figure 2 It is the partial sectional view of the utility model embodiment 1;
[0031] ATTACH Figure 3 It is the overall sectional view of the utility model embodiment 2;
[0032] ATTACH Figure 4 It is the structure enlarged view of part A of the utility model Figure 3
[0033] In the above drawings:
[0034] 100 bearing;
[0035] 200 motor end cover
[0036] 201 bearing chamber
[0037] 202 mounting hole
[0038] 2021 step surface
[0039] 300 locking device
[0040] 1 first shaft cover
[0041] 11 first boss
[0042] 2 elastic connecting assembly
[0043] 21 inner shaft rod
[0044] 211 first stop surface
[0045] 212 second stop surface
[0046] 22 spring
[0047] 3 second shaft cover
[0048] 31 second boss
[0049] 4 long screw DETAILED DESCRIPTION
[0050] The utility model will be further described below in combination with the drawings and examples:
[0051] Examples: the following will be described in detail by the drawings and the present case is clearly explained, any person skilled in the art after understanding the embodiment of the present case, when the technology taught by the present case, is changed and modified, it does not deviate from the spirit and scope of the present case.
[0052] The language in this paper is only for describing specific embodiments, and is not intended to limit the present case. The singular form such as "one", "this", "this", "this" and "the", as used herein, also includes the plural form.
[0053] As for "first", "second" and the like used herein, it is not particularly intended to indicate the order or sequence, nor to limit the present case, which is only for distinguishing components or operations described by the same technical language.
[0054] As for "connection" or "positioning" used herein, it can mean that two or more components or devices are in direct physical contact with each other, or in indirect physical contact with each other, or can mean that two or more components or devices operate or act on each other.
[0055] As for "include", "include", "have" and the like used herein, they are all open terms, that is, they mean include but are not limited to.
[0056] As used herein, the terms have their ordinary meaning in the field of use, unless otherwise indicated specifically. Certain terms used to describe the application are discussed below or elsewhere in the specification to provide additional guidance to the skilled worker in the art regarding descriptions of the application.
[0057] As used herein, the terms "front", "back", "up", "down", "left", "right" and the like refer to directions in the drawings to which they refer, but are not intended to mean that the application is limited to any particular orientation of the application or the specific directions in which the application is implemented. Embodiment
[0058] Referring to the drawings Figures 1-2 A pre-tightening structure of a motor bearing, the bearing 100 is arranged in the bearing chamber 201 of the motor end cover 200, and the inner ring is fixed on the motor rotating shaft by the locking device 300.
[0059] In this embodiment, the locking device 300 can be composed of a check ring + round nut, or other axial locking devices such as a pressing sleeve. One end of the inner ring of the bearing 100 is in contact with the stop step on the motor rotating shaft, and the other end is in contact with the check ring. The round nut is located outside the check ring and is threadedly connected with the rotating shaft. As the round nut is gradually tightened, the check ring and the stop step can clamp and fix the inner ring of the bearing 100.
[0060] In this embodiment, the pre-tightening structure includes a first shaft cover 1 and three elastic connection assemblies 2 connecting the first shaft cover 1 and the motor end cover 200. The three elastic connection assemblies 2 are arranged in a ring array around the shaft center of the motor end cover 200. In other embodiments, four or more elastic connection assemblies 2 can be provided. When four elastic connection assemblies 2 are provided, if one of the elastic connection assemblies 2 fluctuates, the remaining three or more elastic connection assemblies 2 can provide more stable support, and the end face pre-tightening force of the bearing 100 can still be ensured.
[0061] The first shaft cover 1 is movably sleeved on the motor rotating shaft and abuts against one end face of the outer ring of the bearing 100 under the elastic force of the elastic connection assembly 2. Specifically, the first shaft cover 1 abuts against one end face of the outer ring of the bearing 100 through the first boss 11 protruding on the inner end face. The first boss 11 is in close surface contact with the end face of the outer ring of the bearing 100, which can increase the friction of the outer ring of the bearing 100, so that the outer ring of the bearing 100 will not slip and cause the phenomenon of running out of the circle.
[0062] The first boss 11 is in close surface contact with the outer ring end face of the bearing 100, which can transmit relatively stable axial torque, so as to obtain stable resistance torque in the rotation direction, thereby avoiding the phenomenon of bearing 100 running out of the outer ring, and being suitable for occasions with large vibration in the motor application environment.
[0063] The inner end face of the first shaft cover 1 outside the first boss 11 and the motor end cover 200 are reserved with a gap, which can ensure that the bearing 100 and related parts have sufficient adjustment space in the case of thermal expansion and cold contraction.
[0064] The outer peripheral surface of the first boss 11 is in close contact with the inner wall of the bearing chamber 201, which can keep the first shaft cover 1 stable in axial movement, and further make the first shaft cover 1 apply stable axial force to the outer ring of the bearing 100.
[0065] The elastic connection assembly 2 includes an inner shaft rod 21 and a spring 22 sleeved outside the inner shaft rod 21.
[0066] The inner shaft rod 21 penetrates the mounting hole 202 on the motor end cover 200 and is threadedly connected with the first shaft cover 1, the mounting hole 202 has a stepped face 2021, the end of the inner shaft rod 21 away from the first shaft cover 1 has a first stop face 211, and the two ends of the spring 22 are respectively abutted against the stepped face 2021 and the first stop face 211.
[0067] The end of the inner shaft rod 21 close to the first shaft cover 1 has a second stop face 212, which is abutted against the inner end face of the first shaft cover 1.
[0068] The spring 22 is a spiral spring. Since the working stroke of the spiral spring is much larger than that of the wave spring, and the elastic coefficient changes little within the working stroke range of the spiral spring, the pre-tightening force of the spring 22 can be more accurately controlled by controlling the distance between the two stop faces (i.e. replacing the inner shaft rod 21 with a longer distance between the two stop faces), which is suitable for high-speed and super-speed motor occasions with high requirements for pre-tightening force. In addition, the length and elastic coefficient of the spring 22 can also be replaced, but the accuracy is not easy to control.
[0069] In the embodiment, the first shaft cover 1 is arranged on the inner side of the motor end cover 200, which facilitates the installation and replacement of the elastic connection assembly 2 on the outer side of the end cover. In other embodiments, the first shaft cover 1 can also be arranged on the outer side of the motor end cover 200, but the pre-tightening structure needs to be installed with the end cover before the end cover is installed (not shown in the figure). Embodiment
[0070] Referring to the drawings Figures 3-4The embodiment is basically the same as that of the embodiment 1, except that the pre-tightening structure further comprises a second shaft cover 3 movably sleeved on the motor rotating shaft and fixed with the first shaft cover 1 by three long screws 4 penetrating through the motor end cover 200, and the second shaft cover 3 abuts against the other end surface of the outer ring of the bearing 100.
[0071] The long screws 4 and the elastic connecting assemblies 2 are alternately arranged and distributed in a ring array with the shaft center of the motor end cover 200 as the center. In other embodiments, four or more long screws 4 and elastic connecting assemblies 2 can be arranged.
[0072] The second shaft cover 3 abuts against the other end surface of the outer ring of the bearing 100 through a second boss 31 protruding on the end surface, and the second boss 31 is in close surface contact with the end surface of the outer ring of the bearing 100. The inner and outer shaft covers are directly pulled tight with the bearing 100 through the long screws 4, and the friction force of the contact surface between the boss and the outer ring of the bearing 100 can be completely avoided from circumferential sliding under the pulling force of the long screws 4, and the circumferential positioning between the shaft cover and the motor end cover 200 is realized by the long screws 4, so that the outer ring run-out failure of the bearing 100 is completely avoided.
[0073] The inner end surface of the second shaft cover 3 outside the second boss 31 and the motor end cover 200 are reserved with a gap, and the two shaft covers are not axially positioned with the motor end cover 200, so as to ensure that the bearing 100 and related parts have sufficient adjustment space under the conditions of thermal expansion and cold contraction.
[0074] The outer peripheral surface of the second boss 31 is in close contact with the inner wall of the bearing chamber 201, so as to keep the axial movement of the second shaft cover 3 stable, and further make the second shaft cover 3 apply stable axial force to the outer ring of the bearing 100.
[0075] In the embodiment, the first shaft cover 1 is arranged on the inner side of the motor end cover 200, and the second shaft cover 3 is arranged on the outer side of the motor end cover 200.
[0076] The above embodiments are only for illustrating the technical concept and characteristics of the utility model, and the purpose is to enable those skilled in the art to understand the content of the utility model and implement it, and cannot limit the protection scope of the utility model. Any equivalent changes or modifications made according to the spirit and essence of the utility model shall be covered within the protection scope of the utility model.
Claims
1. A preload structure for a motor bearing, wherein the bearing is disposed in a bearing chamber of a motor end cover, and its inner ring is fixed to the motor shaft by a locking device, characterized in that: The pre-tightening structure includes a first shaft cover and a plurality of elastic connecting components connecting the first shaft cover and the motor end cover; The first shaft cover is movably sleeved on the motor shaft and abuts against one end face of the outer ring of the bearing under the elastic force of the elastic connection component; The elastic connection assembly includes an inner shaft and a spring sleeved on the outside of the inner shaft; Wherein: the inner shaft passes through the mounting hole on the motor end cover and is threadedly connected to the first shaft cover; the mounting hole has a stepped surface; the end of the inner shaft away from the first shaft cover has a first stop surface; and the two ends of the spring abut against the stepped surface and the first stop surface, respectively.
2. The preload structure for a motor bearing according to claim 1, characterized in that: The first shaft cover abuts against one end face of the outer ring of the bearing via a first boss protruding from its inner end face. A gap is reserved between the inner end face of the first shaft cover outside the first boss and the motor end cover.
3. The preload structure for a motor bearing according to claim 2, characterized in that: The outer peripheral surface of the first boss is in contact with the inner wall of the bearing chamber.
4. The preload structure for a motor bearing according to claim 2, characterized in that: The inner shaft has a second stop surface at one end near the first shaft cover, which abuts against the inner end surface of the first shaft cover.
5. The preload structure for a motor bearing according to claim 1, characterized in that: The pre-tightening structure also includes a second shaft cover, which is movably sleeved on the motor shaft and is fixed to the first shaft cover by a plurality of long screws passing through the motor end cover. The second shaft cover abuts against the other end face of the outer ring of the bearing.
6. The preload structure for a motor bearing according to claim 5, characterized in that: The second shaft cover abuts against the other end face of the bearing outer ring via a second protrusion on its end face, and a gap is reserved between the inner end face of the second shaft cover outside the second protrusion and the motor end cover.
7. The preload structure for a motor bearing according to claim 6, characterized in that: The outer peripheral surface of the second boss is in contact with the inner wall of the bearing chamber.
8. The preload structure for a motor bearing according to claim 5, characterized in that: The first shaft cover is arranged inside the motor end cover, and the second shaft cover is arranged outside the motor end cover.
9. The preload structure for a motor bearing according to claim 5, characterized in that: The long screw and the elastic connection assembly are provided in at least three parts.
10. The preload structure for a motor bearing according to claim 9, characterized in that: The long screws and the elastic connecting components are alternately arranged and distributed in a circular array centered on the axis of the motor end cover.