Coaxial electric driving device
By setting up a grounding device between the first and second bearings of the coaxial electric drive device, the shaft current is introduced into the bearing seat, the bearing electrical corrosion problem is solved, the service life is extended, the structural compactness is optimized, and the shaft current is realized Effective grounding.
Patent Information
- Application Number
- CN202420735616.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-10
- Publication Date
- 2024-12-13
- Estimated Expiration
- 2034-04-10
AI Technical Summary
In the coaxial electric drive device, the shaft current of the hollow rotor shaft and the output shaft cannot be effectively grounded, resulting in electrical corrosion of the bearing and thus damage.
A coaxial electric drive device including a first and a second bearing is designed, and a shaft current generated on the hollow rotor shaft and the output shaft are introduced into the bearing seat by providing a grounding device between the first and second bearings, thereby Avoid electric corrosion. The grounding device consists of a fixing member and a conductive member. The conductive member comes into contact with the inner ring and the steps of the bearing, and the conductive current is introduced into the bearing seat through the fixing member.
It effectively prevents the electric corrosion of the corresponding bearings of the hollow rotor shaft and the output shaft, extends the service life of the bearing, and solves the electric corrosion problem of multiple bearings simultaneously through a single grounding device, saving space, compact overall structure and reducing costs.
Smart Images
Figure CN222169528U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of transmissions, in particular to a coaxial electric drive device. Background Art
[0002] The coaxial electric drive device for a vehicle includes a motor, a hollow rotor shaft, and a transmission. The rotation (power) of the motor rotor is transmitted to the transmission through the hollow rotor shaft, and the transmission has two output shafts for transmitting power to wheels. One of the output shafts is arranged inside the hollow rotor shaft, and the output shaft coincides with the axis of the hollow rotor shaft.
[0003] During the operation of the coaxial electric drive, shaft currents are generated on the hollow rotor shaft and the output shaft inside it. If there is no special grounding device, the shaft current will flow to the housing through the corresponding bearings of the hollow rotor shaft and / or the output shaft. If it runs like this for a long time, it will cause electrical corrosion of the bearings and then cause bearing damage. Utility Model Content
[0004] In view of the above problems in the prior art, the utility model proposes a coaxial electric drive device with a compact overall structure, which can effectively prevent electrical corrosion of the hollow rotor shaft and / or the corresponding bearings of the output shaft.
[0005] Specifically, the utility model proposes a coaxial electric drive device, comprising:
[0006] Motor;
[0007] Hollow rotor shaft;
[0008] a transmission, to which the rotational power output by the rotor of the motor is transmitted through the hollow rotor shaft; and
[0009] An output shaft, the output shaft is arranged inside the hollow rotor shaft, the hollow rotor shaft and the output shaft are coaxial, and the output shaft is transmission-connected to the transmission;
[0010] The coaxial electric drive device further comprises a first bearing and a second bearing, wherein the first bearing is arranged between the bearing seat and the hollow rotor shaft, and the second bearing is arranged between the bearing seat and the output shaft;
[0011] The coaxial electric drive device further comprises a grounding device, which is axially arranged between the first bearing and the second bearing, and the grounding device is used to introduce the shaft current generated on the hollow rotor shaft and / or the output shaft into the bearing seat.
[0012] According to an embodiment of the utility model, the grounding device includes a fixing member and a conductive member arranged on the fixing member, the fixing member is in contact with the bearing seat, and one end of the conductive member is in contact with the inner ring of the first bearing;
[0013] The shaft current generated on the hollow rotor shaft passes through the inner ring of the first bearing and is then introduced into the bearing seat through the conductive member and the fixing member.
[0014] According to an embodiment of the utility model, the other end of the conductive member is in contact with a step formed on the output shaft;
[0015] The shaft current generated on the output shaft passes through the step of the output shaft and is then introduced into the bearing seat through the conductive member and the fixing member.
[0016] According to an embodiment of the present utility model, the inner ring of the second bearing is in contact with the step.
[0017] According to an embodiment of the utility model, the fixing member is a metal ring, the outer side of the metal ring is in contact with the inner side of the bearing seat, and the conductive member is a carbon brush or a conductive fiber.
[0018] According to an embodiment of the present invention, the metal ring extends radially inward to form a mounting ring, and the plurality of conductive members are arranged on the mounting ring.
[0019] According to an embodiment of the present invention, the plurality of conductive members are evenly distributed along the circumference of the mounting ring.
[0020] According to an embodiment of the present invention, the length direction of the conductive member is parallel to the axis of the hollow rotor shaft.
[0021] According to an embodiment of the present utility model, the coaxial electric drive device further comprises a third bearing, and the third bearing is arranged between the housing of the motor and the hollow rotor shaft on a side opposite to the second bearing.
[0022] According to an embodiment of the present utility model, the third bearing is an insulating bearing.
[0023] According to an embodiment of the present invention, the bearing seat is integrated with the housing of the motor, or is fixedly connected to the housing of the motor.
[0024] According to an embodiment of the present utility model, the first bearing and the second bearing are arranged on a side of the motor away from the transmission.
[0025] The utility model provides a coaxial electric drive device, in which a grounding device is arranged between the first bearing and the second bearing, for introducing the shaft current generated on the hollow rotor shaft and / or the output shaft into the bearing seat. The overall structure is compact and can effectively prevent electrical corrosion of the corresponding bearings of the hollow rotor shaft and / or the output shaft.
[0026] It should be understood that the above general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The accompanying drawings are included to provide a further understanding of the present invention, and they are included and constitute a part of this application. The accompanying drawings illustrate embodiments of the present invention and together with this specification serve to explain the principles of the present invention. In the accompanying drawings:
[0028] Figure 1 The schematic diagram of the structure of a coaxial electric drive device according to an embodiment of the utility model is shown.
[0029] Figure 2 yes Figure 1 A partial enlarged schematic diagram of .
[0030] Figure 3 yes Figure 1 Schematic diagram of the structure of the grounding device.
[0031] The above drawings include the following reference numerals:
[0032] Coaxial electric drive device 100
[0033] Hollow rotor shaft 101
[0034] Output shaft 102
[0035] Bearing seat 103
[0036] Rotor 104
[0037] The third bearing 105
[0038] First bearing 106
[0039] Second bearing 107
[0040] Grounding device 108
[0041] Fixing 109
[0042] Conductive member 110
[0043] Step 111
[0044] Mounting ring 112 DETAILED DESCRIPTION
[0045] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.
[0046] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.
[0047] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.
[0048] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values of the parts and steps set forth in these embodiments do not limit the scope of the present application. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to those of ordinary skill in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be considered as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so that once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.
[0049] In the description of the present application, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, and therefore cannot be understood as limiting the scope of protection of the present application; the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.
[0050] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" may include both "above" and "below". The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.
[0051] In addition, it should be noted that the use of words such as "first" and "second" to define components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above words have no special meaning and cannot be understood as limiting the scope of protection of this application. In addition, although the terms used in this application are selected from well-known and commonly used terms, some terms mentioned in the specification of this application may be selected by the applicant at his or her discretion, and their detailed meanings are explained in the relevant parts of the description of this article. In addition, it is required to understand this application not only by the actual terms used, but also by the meaning implied by each term.
[0052] Figure 1 The schematic diagram of the structure of a coaxial electric drive device according to an embodiment of the utility model is shown. Figure 2 yes Figure 1 As shown in the figure, a coaxial electric drive device 100 mainly includes a motor, a hollow rotor shaft 101, an output shaft 102 and a transmission.
[0053] The rotational power output by the rotor 104 of the motor is transmitted to the transmission through the hollow rotor shaft 101. The output shaft 102 is transmission-connected to the transmission. The output shaft 102 transmits the power to the wheels on one side of the vehicle (not shown). The output shaft 102 is arranged inside the hollow rotor shaft 101, and the axes of the hollow rotor shaft 101 and the output shaft 102 coincide with each other, forming a coaxial structure.
[0054] The coaxial electric drive device 100 further includes a first bearing 106 and a second bearing 107. In this embodiment, the first bearing 106 and the second bearing 107 are arranged on a side of the motor away from the transmission. The first bearing 106 is arranged between the bearing seat 103 and the hollow rotor shaft 101. The second bearing 107 is arranged between the bearing seat 103 and the output shaft 102. It should be noted that the bearing seat 103 can be formed together with the housing of the motor, or the bearing seat 103 is fixedly connected to the housing of the motor. By way of example and not limitation, the bearing seat 103 can also be formed by the end cover of the motor.
[0055] Furthermore, the coaxial electric drive device 100 further includes a grounding device 108. The grounding device 108 is disposed between the first bearing 106 and the second bearing 107. During the operation of the coaxial electric drive device 100, the grounding device 108 is used to guide the shaft current generated on the hollow rotor shaft 101 and / or the output shaft 102 into the bearing seat 103, and then into the housing of the motor, so as to avoid the shaft current from causing electrical corrosion to the first bearing 106 and / or the second bearing 107.
[0056] Figure 3 yes Figure 1 Schematic diagram of the structure of the grounding device. Figure 2 As shown, preferably, the grounding device 108 includes a fixing member 109 and a conductive member 110 disposed on the fixing member 109. The fixing member 109 contacts the bearing seat 103. One end of the conductive member 110 contacts the inner ring of the first bearing 106.
[0057] During the operation of the coaxial electric drive device 100, the shaft current generated on the hollow rotor shaft 101 passes through the inner ring of the first bearing 106, and the shaft current is then sequentially introduced into the bearing seat 103 through the conductive member 110 and the fixing member 109. By providing the grounding device 108, the shaft current originally flowing through the first bearing 106 is guided from the grounding device 108 to the bearing seat 103, and then introduced into the housing of the motor, thereby protecting the first bearing 106 from electrical corrosion and extending the service life of the first bearing 106.
[0058] Preferably, the other end of the conductive member 110 contacts a step 111 formed on the output shaft 102 .
[0059] During the operation of the coaxial electric drive device 100, the shaft current generated on the output shaft 102 passes through the step 111 of the output shaft 102, and then is introduced into the bearing seat 103 through the conductive member 110 and the fixing member 109 in sequence, and then is introduced into the housing of the motor. In the prior art, the shaft current generated on the output shaft 102 is introduced into the housing of the motor through the second bearing 107. By adopting the grounding device 108 provided by the utility model, the shaft current originally flowing through the second bearing 107 is guided from the grounding device 108 to the bearing seat 103, and then is introduced into the housing of the motor, thereby avoiding the shaft current flowing through the second bearing 107 and generating electrical corrosion, and extending the service life of the second bearing 107. It is easy to understand that although a grounding device 108 can be separately configured for the first bearing 106 and the second bearing 107 to solve the problem of electrical corrosion, the single grounding device 108 in this embodiment can solve the electrical corrosion problem of the first bearing 106 and the second bearing 107 at the same time, saving the installation space of a grounding device, shortening the axial space of the coaxial electric drive device 100, making the overall structure more compact, and effectively reducing costs.
[0060] Preferably, the inner ring of the second bearing 107 contacts the step 111. The step 111 formed on the output shaft 102 has a limiting effect on the second bearing 107, which facilitates the assembly of the second bearing 107. The shaft current that may flow through the second bearing 107 passes through the step 111 from the inner ring of the second bearing 107, and then is introduced into the bearing seat 103 through the grounding device 108, and then introduced into the housing of the motor, so that the second bearing 107 can be provided with electrical corrosion protection.
[0061] Preferably, reference Figure 3 The fixing member 109 is a metal ring. The outer side of the metal ring is in contact with the inner side of the bearing seat 103, and the conductive member 110 is a carbon brush or conductive fiber. Among them, carbon brushes are widely used in many electrical devices as a sliding contact. The materials of carbon brushes mainly include electrochemical graphite, impregnated graphite, and metal (containing copper and silver) graphite, which have good commutation performance and long service life.
[0062] Preferably, a mounting ring 112 is formed by extending radially inwardly of the metal ring, and a plurality of conductive members 110 are disposed on the mounting ring 112. More preferably, the plurality of conductive members 110 are evenly distributed along the circumference of the mounting ring 112.
[0063] Preferably, the length direction of the conductive member 110 is parallel to the axis of the hollow rotor shaft 101 .
[0064] Preferably, the coaxial electric drive device 100 further includes a third bearing 105. The third bearing 105 is arranged between the housing of the motor and the hollow rotor shaft 101 on the side opposite to the second bearing 107.
[0065] Preferably, the third bearing 105 is an insulating bearing. As an example and not a limitation, the insulating bearing may be a ceramic ball bearing, the service life of which is 2-3 times that of an ordinary bearing. One of the most important features of a ceramic ball bearing is insulation. By using a ceramic ball bearing, the inner and outer rings of the bearing can be insulated, because the ceramic ball is an insulator. By using a ceramic ball between the inner and outer rings of the bearing, the insulation effect can be achieved, so that the bearing can be used in a conductive environment. After the third bearing 105 adopts an insulating bearing, the shaft current formed on the hollow rotor shaft 101 and the output shaft 102 passes through the inner rings corresponding to the first bearing 106 and the second bearing 107, and is introduced into the bearing seat 103 via the grounding device 108, and then introduced into the housing of the motor, thereby avoiding electrical corrosion of the first bearing 106 and the second bearing 107, and extending the service life of the first bearing 106 and the second bearing 107.
[0066] The utility model provides a coaxial electric drive device, which has the following advantages:
[0067] Provide electrical corrosion protection for the hollow rotor shaft and the corresponding bearings of the output shaft;
[0068] A single grounding device is used, which occupies less space, shortens the axial space, makes the overall structure more compact, and effectively reduces costs.
[0069] It will be apparent to those skilled in the art that various modifications and variations can be made to the above exemplary embodiments of the present invention without departing from the spirit and scope of the present invention. Therefore, it is intended that the present invention covers modifications and variations of the present invention that fall within the scope of the appended claims and their equivalent technical solutions.
Claims
1. A coaxial electric drive device, characterized in that: include: Motor; Hollow rotor shaft; a transmission, to which the rotational power output by the rotor of the motor is transmitted through the hollow rotor shaft; and An output shaft, the output shaft is arranged inside the hollow rotor shaft, the hollow rotor shaft and the output shaft are coaxial, and the output shaft is drivingly connected to the transmission; The coaxial electric drive device further comprises a first bearing and a second bearing, wherein the first bearing is arranged between the bearing seat and the hollow rotor shaft, and the second bearing is arranged between the bearing seat and the output shaft; The coaxial electric drive device further comprises a grounding device, which is axially arranged between the first bearing and the second bearing, and the grounding device is used to introduce the shaft current generated on the hollow rotor shaft and / or the output shaft into the bearing seat.
2. The coaxial electric drive device according to claim 1, characterized in that: The grounding device includes a fixing member and a conductive member arranged on the fixing member, the fixing member is in contact with the bearing seat, and one end of the conductive member is in contact with the inner ring of the first bearing; The shaft current generated on the hollow rotor shaft passes through the inner ring of the first bearing and is then introduced into the bearing seat through the conductive member and the fixing member.
3. The coaxial electric drive device according to claim 2, characterized in that: The other end of the conductive member is in contact with a step formed on the output shaft; The shaft current generated on the output shaft passes through the step of the output shaft and is then introduced into the bearing seat through the conductive member and the fixing member.
4. The coaxial electric drive device according to claim 3, characterized in that: The inner ring of the second bearing is in contact with the step.
5. The coaxial electric drive device according to any one of claims 2 to 4, characterized in that: The fixing member is a metal ring, the outer side of the metal ring is in contact with the inner side of the bearing seat, and the conductive member is a carbon brush or conductive fiber.
6. The coaxial electric drive device according to claim 5, characterized in that: The metal ring extends radially inward to form a mounting ring, and a plurality of the conductive members are arranged on the mounting ring.
7. The coaxial electric drive device according to claim 6, characterized in that: The plurality of conductive members are evenly distributed along the circumference of the mounting ring.
8. The coaxial electric drive device according to claim 7, characterized in that: The length direction of the conductive member is parallel to the axis of the hollow rotor shaft.
9. The coaxial electric drive device according to claim 1, characterized in that: The coaxial electric drive device further comprises a third bearing which is arranged between the housing of the electric motor and the hollow rotor shaft on a side opposite to the second bearing.
10. The coaxial electric drive device according to claim 9, characterized in that: The third bearing is an insulating bearing.
11. The coaxial electric drive device according to claim 1, characterized in that: The bearing seat is integrated with the housing of the motor or fixedly connected to the housing of the motor.
12. The coaxial electric drive device according to claim 1, characterized in that: The first bearing and the second bearing are arranged on a side of the motor away from the transmission.