CN220857768U

CN220857768U - Shafting structure for preventing bearing shaft from being electrically damaged

Info

Publication number: CN220857768U
Application number: CN202322472969.6U
Authority: CN
Inventors: 王坤; 张毅; 刘家臻
Original assignee: United Automotive Electronic Systems Co Ltd
Current assignee: United Automotive Electronic Systems Co Ltd
Priority date: 2023-09-12
Filing date: 2023-09-12
Publication date: 2024-04-26
Anticipated expiration: 2033-09-12

Abstract

The utility model relates to the technical field of shafting design, in particular to a shafting structure for preventing bearing electric damage, which comprises an insulating bush, wherein the insulating bush is sleeved on the outer side of a bearing and is positioned between the bearing and a motor shell, the insulating bush comprises a bush body and an insulating layer, the bush body is provided with a cavity for accommodating the bearing, the insulating layer covers the inner wall of the cavity and/or the outer wall of the bush body, and the transmission of annular current between the bearing and the motor shell can be effectively blocked by arranging the insulating bush between the bearing and the motor shell, so that the bearing is prevented from being damaged electrically. In addition, compared with a ceramic rotor, the insulating bush has simple manufacturing process and lower cost, and can be applied in a large scale.

Description

Shafting structure for preventing bearing shaft from being electrically damaged

Technical Field

The utility model relates to the technical field of shafting design, in particular to a shafting structure for preventing bearing electric damage.

Background

Shaft electricity is a common phenomenon of a high-speed motor, shaft electricity caused by high-frequency signals forms shaft voltage at the inner ring and the outer ring of a bearing, and when the voltage magnitude reaches a certain degree, bearing grease is broken down, a bearing rotor track and bearing balls are damaged. The shaft current is divided into two types, one of which is an annular current formed between the motor shaft, the drive and non-drive end bearing 1 and the motor housing 2, which is an induced current generated in the rotor by the motor stator, as shown by the path of the arrow in fig. 1; the other is a current flowing from the bearing inner and outer rings toward the housing, also called EDM current, as shown by the path of the arrows in fig. 2. In practical applications, both shaft currents coexist.

At present, the damage of annular current to the bearing is solved, and a blocking method is mainly adopted, namely, insulation treatment is carried out on the rotor body or the inner ring and the outer ring of the bearing. The former is mainly used at present as a ceramic rotor 3, and a ceramic with high insulation and high hardness is used as the rotor, so that the bearing is ensured to bear and wear resistance, and meanwhile, the insulation of the bearing is ensured, as shown in fig. 3. The scheme is a mainstream choice because of good insulation effect, but the price is often high because of complex process; the latter generally uses an insulation spray method of spraying an insulation layer 4 such as alumina or the like on the inner and outer rings of the bearing, as shown in fig. 4. The main disadvantage of this method is that the insulating layer is generally thin, about 0.1 micron, and if the coating is too thick, it is easy to drop off, and the insulating effect is poor. In addition, the coating of the bearing body needs to protect other parts, and the spraying process is complex.

For EDM current, a guiding method is mainly adopted, namely a path with relatively small resistance is provided, and the current on the rotating shaft is directly guided to the shell by using the conducting ring 5, so that damage to the bearing is avoided. Currently, a relatively large number of conductive ring products are used in the industry, as shown in fig. 5. The conductive ring 5 has a relatively good suppression effect on EDM current, but is a separate component at relatively high cost.

Disclosure of utility model

The utility model aims to provide a shafting structure for preventing bearing electric damage, which at least solves one of the technical problems existing in shafting design for preventing bearing electric damage in the prior art.

In order to achieve the above object, the present utility model provides a shafting structure for preventing bearing from electrical damage, comprising an insulating bushing, wherein the insulating bushing is sleeved outside a bearing and is located between the bearing and a motor housing, the insulating bushing comprises a bushing body and an insulating layer, the bushing body is provided with a cavity for accommodating the bearing, and the insulating layer covers the inner wall of the cavity and/or the outer wall of the bushing body.

Optionally, the upper surface of the liner sleeve body is provided with a concave area, and the insulating layer extends to cover the concave area.

Optionally, the material of the bushing body is metal.

Optionally, the bushing body is formed by stamping.

Optionally, the insulating layer is made of rubber.

Optionally, the bushing body and the insulating layer are integrally bonded through vulcanization.

Optionally, the shafting structure for preventing bearing shaft from electric damage further comprises an oil seal assembly, wherein the oil seal assembly comprises an oil seal ring and a conducting ring, the oil seal ring and the conducting ring are sleeved outside the rotating shaft, and the oil seal ring is embedded at the inner ring surface of the conducting ring.

Optionally, a bending part is disposed at an outer edge of the conductive ring, and the bending part is disposed along a circumferential direction of the conductive ring.

Optionally, a ring of lips is arranged on the inner ring surface of the oil seal ring, and the lips are abutted with the outer wall of the rotating shaft.

Optionally, a notch is formed on a side of the lip facing away from the rotating shaft.

The shafting structure for preventing bearing electric damage provided by the utility model has at least one of the following beneficial effects:

1) Through set up an insulation bush between bearing and motor casing, can block the annular electric current's between bearing and the motor casing transmission effectively, and then prevent that the bearing from taking place the axle electric damage. In addition, compared with the ceramic rotor, the insulating bush has simple manufacturing process and lower cost, and can be applied in a large scale;

2) The concave area is arranged on the upper surface of the bushing body, so that on one hand, sealing can be ensured when the top mold is closed, rubber and the metal bushing are better combined after molding, partial falling is prevented, on the other hand, a certain limiting effect can be achieved on the bearing, the bearing is prevented from axially moving in a stringing way, and as the rubber has a certain elasticity, impact load on the bearing in the axial direction can be buffered, and after the load disappears, resilience force can be provided, and noise is reduced while axial impact force of the bearing is reduced;

3) Through with current oil seal ring and conducting ring integrated design as an organic whole, not only kept the oil blanket effect, still have the conducting effect of conducting ring concurrently, can be with the direct guide of axle current to motor housing on the rotation axis, the ground point that again passes through motor housing draws forth, avoids EDM electric current to cause the damage to the bearing. In addition, the conducting ring is integrated and embedded into the oil seal ring, so that one part can be saved, the arrangement space is saved, and the cost is greatly reduced;

4) Through setting up the kink at the outward flange of conducting ring, the kink can absorb the run-out of high-speed rotation axis through self deformation buffering, prevents the striking of lip and rotation axis.

Drawings

It will be appreciated by those skilled in the art that the drawings are provided for a better understanding of the utility model and do not constitute any limitation on the scope of the utility model. Wherein:

FIG. 1 is a schematic diagram of a path of a circular current in the prior art;

FIG. 2 is a schematic diagram of the path of EDM current in the prior art;

FIG. 3 is a schematic view of a prior art bearing employing a ceramic rotor;

FIG. 4 is a schematic illustration of prior art coating of an insulating layer on the inner and outer races of a bearing;

FIG. 5 is a schematic diagram of a prior art conductive ring;

FIG. 6 is a schematic view of an insulation bushing according to an embodiment of the present utility model;

FIG. 7 is a schematic view of an embodiment of the present utility model, wherein an insulating bush is disposed outside a bearing;

FIG. 8 is a schematic structural diagram of an oil seal assembly according to an embodiment of the present utility model;

Fig. 9 is an overall schematic diagram of a shafting structure for preventing bearing electrical damage according to an embodiment of the present utility model.

Wherein:

1-a bearing; 2-a motor housing; 3-ceramic rotors; 4-an insulating layer; a 5-conducting ring;

10-insulating bushings; 11-a bushing body; 12-an insulating layer; 13-a cavity; 20-bearing; 30-a motor housing; 40-an oil seal assembly; 41-an oil seal ring; 42-conducting rings; 50-rotation axis.

110-A recessed region; 410-lips; 420-bending part.

Detailed Description

The utility model will be described in further detail with reference to the drawings and the specific embodiments thereof in order to make the objects, advantages and features of the utility model more apparent. It should be noted that, the drawings are in very simplified form and all use non-precise proportions, which are only used for the purpose of conveniently and clearly assisting in explaining the embodiments of the present utility model, and are not intended to limit the implementation conditions of the present utility model, so that the present utility model has no technical significance, and any modification of the structure, change of the proportional relation or adjustment of the size, without affecting the efficacy and achievement of the present utility model, should still fall within the scope covered by the technical content disclosed by the present utility model.

It should be further understood that the terms "first," "second," "third," and the like in this specification are used merely for distinguishing between various components, elements, steps, etc. in the specification and not for indicating a logical or sequential relationship between the various components, elements, steps, etc., unless otherwise indicated. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises an element.

On the one hand, referring to fig. 6 and 7, the present embodiment provides a shafting structure for preventing bearing shaft from being electrically damaged, which comprises an insulation bushing 10, wherein the insulation bushing 10 is sleeved outside a bearing 20 and is located between the bearing 20 and a motor housing 30, the insulation bushing 10 comprises a bushing body 11 and an insulation layer 12, the bushing body 11 is provided with a cavity 13 for accommodating the bearing 20, and the insulation layer 12 covers the inner wall of the cavity 13 and/or the outer wall of the bushing body 11.

By providing an insulating bush 10 between the bearing 20 and the motor housing 30, the transmission of the annular current between the bearing 20 and the motor housing 30 can be effectively blocked, thereby preventing the bearing 20 from being electrically damaged. In addition, compared with the ceramic rotor, the insulating bush 10 has simple manufacturing process and lower cost and can be applied in a large scale.

In this embodiment, the bushing body 11 is of an annular structure, and the insulating layer 12 has three coating modes on the bushing body 11, that is, the insulating layer 12 coats the inner wall of the cavity 13, the insulating layer 12 coats the outer wall of the bushing body 11, and the insulating layer 12 coats the inner wall of the cavity 13 and the outer wall of the bushing body 11, so that the three coating modes can all play an insulating role, effectively block the transmission of annular current between the bearing 20 and the motor housing 30, and prevent the bearing 20 from being damaged by axial electricity.

Preferably, the material of the bushing body 11 is metal, such as steel, aluminum alloy, etc., and can be manufactured and formed by stamping or machining, the material of the insulating layer 12 is rubber, and the bushing body 11 and the insulating layer 12 are integrally bonded through vulcanization. Therefore, the whole insulation bushing 10 has a simple structure and low manufacturing process requirements, so that the cost is greatly reduced.

Preferably, the upper surface of the liner sleeve body 11 has a recessed area 110, and the insulating layer 12 extends to cover the recessed area 110. Through set up the seal gum when the upper surface at bush body 11 can guarantee the top mould compound die on the one hand, make rubber and metal bush combine better after the shaping, prevent that the part from coming off, on the other hand can play certain limiting displacement to bearing 20, prevent that bearing 20 from moving in the axial direction, and because rubber possesses certain elasticity, can cushion the impact load that bearing 20 received in the axial direction to can provide the resilience force after the load disappears, reduce noise when reducing bearing 20 axial impact force.

Preferably, the rubber thickness should be as thin as possible in order to ensure that the displacement amount is satisfactory when the rubber is subjected to radial force after being pressed into the housing.

Further, referring to fig. 8 in combination with fig. 9, the shafting structure for preventing bearing electrical damage further includes an oil seal assembly 40, the oil seal assembly 40 includes an oil seal ring 41 and a conductive ring 42, the oil seal ring 41 and the conductive ring 42 are both sleeved outside the rotating shaft 50, and the oil seal ring 41 is embedded in an inner ring surface of the conductive ring 42.

Through the integrated design as an organic whole with current oil blanket ring 41 and conducting ring 42, not only kept the oil blanket effect, still have the conducting effect of conducting ring 42 concurrently, can direct the motor casing 30 with the axle electric current from rotation axis 50 on, draw forth through the ground point of motor casing 30 again, avoid EDM electric current to cause the damage to bearing 20. In addition, the conductive ring 42 is integrally embedded into the oil seal ring 41, so that one part can be saved, the arrangement space is saved, and the cost is greatly reduced.

Preferably, the inner ring surface of the oil seal ring 41 is provided with a ring of lips 410, and the lips 410 are abutted against the outer wall of the rotating shaft 50.

Preferably, the side of the lip 410 facing away from the rotational axis 50 has a notch. The notch is arranged to ensure effective contact with the shaft and prevent excessive friction loss caused by excessive contact force.

Preferably, the outer edge of the conductive ring 42 is provided with a bending part 420, and the bending part 420 is disposed along the circumferential direction of the conductive ring 42. The bending part 420 can absorb the runout of the high-speed rotating shaft 50 through self deformation buffering, and the lip 410 is prevented from colliding with the rotating shaft 50.

In summary, the present utility model provides a shafting structure for preventing bearing from being electrically damaged, on the one hand, by disposing an insulating bushing 10 between the bearing 20 and the motor housing 30, the transmission of annular current between the bearing 20 and the motor housing 30 can be effectively blocked, so as to prevent the bearing 20 from being electrically damaged. In addition, compared with the ceramic rotor, the insulating bush 10 has simple manufacturing process and lower cost and can be applied in a large scale. On the other hand, through the integrated design as an organic whole with current oil blanket ring 41 and conducting ring 42, not only kept the oil blanket effect, still have the conducting effect of conducting ring 42 concurrently, can direct the motor casing 30 with the axle electric current from rotation axis 50 on, draw forth through the ground point of motor casing 30 again, avoid EDM electric current to cause the damage to bearing 20. In addition, the conductive ring 42 is integrally embedded into the oil seal ring 41, so that one part can be saved, the arrangement space is saved, and the cost is greatly reduced.

It should also be appreciated that while the present utility model has been disclosed in the context of a preferred embodiment, the above embodiments are not intended to limit the utility model. Many possible variations and modifications of the disclosed technology can be made by anyone skilled in the art without departing from the scope of the technology, or the technology can be modified to be equivalent. Therefore, any simple modification, equivalent variation and modification of the above embodiments according to the technical substance of the present utility model still fall within the scope of the technical solution of the present utility model.

Claims

1. The utility model provides a prevent shafting structure of bearing axle electric damage, its characterized in that includes insulating bush, insulating bush cover is established in the outside of bearing and be located between bearing and the motor casing, insulating bush includes bush body and insulating layer, the bush body has the cavity that is used for holding the bearing, insulating layer cladding the inner wall of cavity and/or the outer wall of bush body.

2. The shafting structure for preventing bearing electrical damage according to claim 1, wherein the upper surface of the bushing body has a recessed area, and the insulating layer extends and covers the recessed area.

3. The shafting structure for preventing bearing electrical damage according to claim 1, wherein the bushing body is made of metal.

4. A shafting structure for preventing bearing electrical damage according to claim 3, wherein the bushing body is stamped.

5. A shafting structure for preventing bearing electrical damage according to claim 3, wherein the insulating layer is made of rubber.

6. The shafting structure for preventing bearing electrical damage according to claim 5, wherein the bushing body and the insulating layer are integrally bonded by vulcanization.

7. The shafting structure for preventing bearing electric damage according to claim 1, further comprising an oil seal assembly, wherein the oil seal assembly comprises an oil seal ring and a conductive ring, the oil seal ring and the conductive ring are both sleeved outside a rotating shaft, and the oil seal ring is embedded at an inner ring surface of the conductive ring.

8. The shafting structure for preventing bearing electrical damage according to claim 7, wherein the outer edge of the conductive ring is provided with a bending portion, and the bending portion is arranged along the circumferential direction of the conductive ring.

9. The shafting structure for preventing bearing electric damage according to claim 7, wherein the inner ring surface of the oil seal ring is provided with a ring of lips, and the lips are abutted against the outer wall of the rotating shaft.

10. The shafting structure for preventing bearing electrical damage according to claim 9, wherein the lip has a notch on a side facing away from the rotational axis.