Shaft current prevention structure
The ceramic ball bearing and conductive ring structure diverts and isolates axis current, protecting bearings from electrical discharge and corrosion, enhancing the durability and reliability of the electrical drive system.
Patent Information
- Application Number
- CN202422087319.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-27
- Publication Date
- 2025-07-15
- Estimated Expiration
- 2034-08-27
AI Technical Summary
The bearing damage caused by shaft current, which is difficult to effectively prevent in the prior art.
The ceramic ball bearing and conductive ring structure are adopted. The inner ring and outer ring of the ceramic ball bearing are isolated by ceramic ball. The conductive ring guides the shaft current to the grounding of the shell, forming a bypass measure.
Effectively isolate DC and AC currents, protect bearings, prevent bearing damage, extend equipment service life, and reduce faults and downtime.
Smart Images
Figure CN223109838U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of the structural design of an electric drive system, and particularly relates to a structure for preventing shaft current. Background Art
[0002] Shaft current is the current flowing through the motor shaft, bearings to the housing. Shaft current will leave a corrugated pattern similar to a washboard on the raceways of the inner and outer rings of the rolling bearing. This is because when the shaft current flows through the contact surface between the raceway and the rolling element, discharge sparks are generated, melting the local metal material. The melted material is rolled by the high-speed rotating inner ring and rolling elements to form a corrugated pattern. For the sliding bearing, it will form traces of discharge spark burning on the surface of the bearing alloy. These will cause serious damage to the bearings.
[0003] Therefore, it is necessary to design a structure that can effectively prevent shaft current. Summary of the Utility Model
[0004] Based on the above description, the utility model provides a structure for preventing shaft current to solve the technical problem of bearing damage caused by shaft current in the prior art.
[0005] The technical solution of the utility model to solve the above technical problems is as follows:
[0006] A structure for preventing shaft current, which includes a shaft, a housing, a ceramic ball bearing and a conductive ring;
[0007] The shaft is rotatably installed in the housing;
[0008] The housing is a conductor;
[0009] The ceramic ball bearing includes an inner ring, ceramic balls and an outer ring. The inner ring is sleeved on the shaft, the outer ring is embedded in the housing, and the ceramic balls are arranged between the inner ring and the outer ring to enable the inner ring and the outer ring to rotate freely;
[0010] The conductive ring is installed inside the housing. The inner side of the conductive ring is sleeved on the outer side of the shaft, and the outer side of the conductive ring is fixed to the housing. The conductive ring is used to guide the shaft current generated on the shaft to the housing.
[0011] Compared with the prior art, the technical solution of the present application has the following beneficial technical effects:
[0012] The structure for preventing shaft current provided by this application uses ceramic balls as a measure to break the shaft current. Ceramic balls are used to isolate the inner ring and the outer ring of the ceramic ball bearing, effectively preventing the formation of a current path between the inner ring and the outer ring. It can isolate direct current and alternating current and has a good over-current protection effect. The conducting ring is a bypass measure for preventing shaft current. The inner side of the conducting ring contacts the rotating shaft, and the outer side is installed on the housing to form a ground connection. When there is shaft voltage, almost all of the shaft current passes through the conducting ring, and the current passing through the bearing is very small, which plays a role in protecting the electric drive system, especially the bearing.
[0013] Based on the above technical solutions, the present utility model can be further improved as follows.
[0014] Further, the conducting ring includes a ring body and a conductive fiber brush. The ring body is fixed on the housing, and the conductive fiber brush is connected to the inner side of the ring body and contacts the outer surface of the rotating shaft.
[0015] Further, the conductive fiber brushes are evenly spaced circumferentially along the inner side of the ring body.
[0016] Further, the rotating shaft is a motor rotating shaft or a generator rotating shaft.
[0017] Further, the housing is a metal housing. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 It is a schematic cross-sectional structure diagram of a structure for preventing shaft current provided by an embodiment of this application;
[0019] Figure 2 It is a schematic cross-sectional structure diagram of a ceramic ball bearing in an embodiment of this application;
[0020] Figure 3 It is a schematic structure diagram of a conducting ring in an embodiment of this application. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0021] To facilitate the understanding of this application, the following will describe this application more comprehensively with reference to the relevant drawings. Embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of this application more thorough and comprehensive.
[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this application belongs. The terms used in the specification of this application herein are only for the purpose of describing specific embodiments and are not intended to limit this application.
[0023] It will be appreciated that spatial relationship terms such as "under", "below", "beneath", "underneath", "above", "over" etc. may be used herein to describe the relationship of one element or feature shown in the figures to other elements or features. It should be understood that, in addition to the orientation shown in the figures, spatial relationship terms also include different orientations of the device in use and operation. For example, if the device in the accompanying drawings is flipped, an element or feature described as "under other elements" or "beneath it" or "under it" will be oriented "above" the other elements or features. Thus, the exemplary terms "under" and "beneath" can include both the upper and lower orientations. In addition, the device may also have other orientations (such as rotated 90 degrees or other orientations), and the spatial descriptors used herein are accordingly interpreted.
[0024] It should be noted that when an element is considered to be "connected" to another element, it can be directly connected to the other element or connected to the other element through an intermediate element. In the following embodiments, "connection", if there is a transfer of electrical signals or data between the connected circuits, modules, units, etc., should be understood as "electrical connection", "communication connection", etc.
[0025] As used herein, the singular forms "a", "an" and "the" may also include the plural forms unless the context clearly dictates otherwise. It should also be understood that the terms "comprise / include" or "have" etc. specify the presence of the stated features, wholes, steps, operations, components, parts or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts or combinations thereof.
[0026] As Figures 1-3 shown, an embodiment of the present application provides an anti-shaft current structure, which includes a rotating shaft 10, a housing 20, a ceramic ball bearing 30 and a conductive ring 40.
[0027] Wherein, the rotating shaft 10 is rotatably installed in the housing 20. Specifically, at least a part of the rotating shaft 10 is rotatably connected to the housing 20 through the ceramic ball bearing 30. The rotating shaft 10 may or may not adopt other rotational connection measures, which are not limited herein.
[0028] Wherein, the housing 20 is a conductor, preferably a metal housing, for conducting electricity to ground.
[0029] The ceramic ball bearing 30 includes an inner ring 31, ceramic balls 32 and an outer ring 33. The inner ring 31 is sleeved on the rotating shaft 10, the outer ring 33 is embedded in the housing 20, and the ceramic balls 32 are arranged between the inner ring 31 and the outer ring 33 to enable the inner ring 31 and the outer ring 32 to rotate freely.
[0030] The conductive ring 40 is installed inside the housing 20. The inner side of the conductive ring 40 is sleeved outside the rotating shaft 10, and the outer side of the conductive ring 40 is fixed to the housing 20. The conductive ring 40 is used to guide the shaft current generated on the rotating shaft 10 to the housing 20.
[0031] For the anti-shaft current structure provided by this application, using the ceramic ball bearing 30 is an anti-shaft current open-circuit measure. The inner ring 31 and the outer ring 33 of the ceramic ball bearing 30 are isolated by ceramic balls, effectively avoiding the formation of a current path between the inner ring 31 and the outer ring 33, being able to isolate direct current and alternating current, and having a good over-current protection effect; in addition, the ceramic balls 32 have characteristics such as low density, high hardness, and wear resistance, being suitable for high-speed rotation working conditions.
[0032] The conductive ring 40 is an anti-shaft current bypass measure. The inner side of the conductive ring 40 is in contact with the rotating shaft, and the outer side is installed on the housing to form a ground connection. When there is shaft voltage, almost all of the shaft current passes through the conductive ring 40, and the current passing through the bearing will be very small, playing a role in protecting the electric drive system, especially the bearing.
[0033] In this embodiment, the conductive ring 40 includes a ring body 41 and a conductive fiber brush 42. The ring body 41 is fixed on the housing 20, and the conductive fiber brush 42 is connected to the inner side of the ring body 41 and contacts the outer surface of the rotating shaft 20. The design of the conductive ring 40 is optimized for transmitting shaft current, ensuring that the shaft current generated during the rotation of the rotating shaft 20 can be safely and efficiently transmitted through the conductive fiber brush 42 to the ring body 41, and then further transmitted to the housing 20 or other grounded components, preventing equipment damage or performance degradation caused by the accumulation of shaft current.
[0034] The timely derivation of shaft current helps prevent corrosion and wear of the rotating shaft 20 and its surrounding components, thereby extending the service life of the equipment. In addition, the design of the conductive ring 41 also reduces equipment failures and downtime caused by shaft current problems.
[0035] In the embodiment of this application, the rotating shaft 10 can be a motor rotating shaft or a generator rotating shaft.
[0036] The above are only the preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.
Claims
1. A structure for preventing shaft current, characterized in that, It includes a rotating shaft, a housing, a ceramic ball bearing and a slip ring; The rotating shaft is rotatably installed in the housing; The housing is a conductor; The ceramic ball bearing includes an inner ring, ceramic balls and an outer ring. The inner ring is sleeved on the rotating shaft, the outer ring is embedded in the housing, and the ceramic balls are arranged between the inner ring and the outer ring to enable the inner ring and the outer ring to rotate freely; The slip ring is installed inside the housing. The inner side of the slip ring is sleeved on the outer side of the rotating shaft, and the outer side of the slip ring is fixed to the housing. The slip ring is used to guide the shaft current generated on the rotating shaft to the housing.
2. The anti-axial current structure according to claim 1, characterized in that, The slip ring includes a ring body and conductive fiber brushes. The ring body is fixed on the housing, and the conductive fiber brushes are connected to the inner side of the ring body and contact the outer surface of the rotating shaft.
3. The structure for preventing shaft current according to claim 2, wherein, The conductive fiber brushes are arranged at equal intervals along the circumferential direction of the inner side of the ring body.
4. The structure for preventing shaft current according to claim 1, characterized in that, The rotating shaft is a motor rotating shaft or a generator rotating shaft.
5. The structure for preventing shaft current according to claim 1, characterized in that, The housing is a metal housing.