Shaft current elimination structure of oil-cooled motor

Abstract

The utility model discloses a shaft current elimination structure of an oil-cooled motor, which comprises a motor spindle, an end cover and a casing, a spring and a conductor are mounted on the end cover, the conductor is in contact conduction with the end cover, and one end, far away from the spring, of the conductor is in contact with a spindle head of the motor spindle; a spring and an electric conductor are mounted on the motor spindle, the electric conductor is in contact conduction with the motor spindle, and one end, far away from the spring, of the electric conductor is in contact with the end cover spindle head. According to the utility model, the spring and the conductor are arranged on the motor main shaft, or the spring and the conductor are arranged on the end cover, both the spring and the conductor can ensure real-time contact between the conductor and the motor main shaft, the contact performance is good, shaft current can be eliminated in the oil-cooled motor, the conductor is protected, and oil is prevented from being sprayed on the conductor to influence the conductive effect; the device is simple in overall structure, good in manufacturability, convenient to maintain, low in cost and suitable for large-scale application and popularization.

Description

Technical Field

[0001] This utility model belongs to the field of oil-cooled motor technology, and specifically relates to a shaft current elimination structure for an oil-cooled motor. Background Technology

[0002] With the acceleration of electrification in the automotive industry, the market's performance requirements for drive motors are increasingly moving towards higher speeds and higher voltages. During operation, the motor generates shaft voltage between the inner and outer rings of the bearing due to factors such as high-order harmonics in the power supply and magnetic circuit imbalance. Excessive shaft voltage can break down the bearing oil film and generate shaft current. The generation of shaft current can lead to electro-corrosion patterns on the inner and outer rings of the bearing, which seriously affects the service life of the bearing and the motor.

[0003] Currently, shaft current is generally eliminated by installing insulated bearings, but this method will significantly increase the cost of the motor. Another method is to eliminate shaft current by installing grounding carbon brushes, but the grounding carbon brushes will wear off and fall off after rubbing against the motor shaft. The fallen foreign objects will reduce the insulation performance of the motor or even cause insulation failure. Moreover, the grounding carbon brushes are wear parts, which are not easy to disassemble and install, resulting in high maintenance costs.

[0004] Chinese Patent Announcement No. CN213367588U discloses an shaft current elimination mechanism, a drive motor, and an electric vehicle. The solution includes: installing a conductive bolt at the end of the main shaft, installing a conductive spherical body at the end of the bolt, and installing an elastic conductor at the end of the end cap. The shaft current is eliminated by the contact between the elastic conductor and the conductive spherical body.

[0005] This patent has the following drawbacks:

[0006] 1. Requires special bolts and spherical conductors, resulting in higher costs;

[0007] 2. In oil-cooled motors, a contact oil film will form, leading to poor contact;

[0008] 3. There is a risk that the bolts fixing the elastic conductor may fall off, which could damage the internal components of the motor. Utility Model Content

[0009] The main purpose of this invention is to provide a shaft current elimination structure for oil-cooled motors, which solves the problems of contact oil film and unstable contact in existing shaft current elimination structures for oil-cooled motors on the market.

[0010] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a shaft current elimination structure for an oil-cooled motor, comprising a motor main shaft, an end cover, and a housing, wherein a spring and a conductor are installed on the end cover, the conductor is in contact with the end cover and conducts electricity, and the end of the conductor away from the spring is in contact with the shaft head of the motor main shaft, and also includes an oil seal.

[0011] Furthermore, it includes a motor spindle, an end cover, and a housing. A spring and a conductor are installed on the motor spindle. The conductor is in contact with the motor spindle and conducts electricity. The end of the conductor away from the spring is in contact with the shaft end of the end cover. It also includes an oil seal.

[0012] Furthermore, the end cap is provided with a stepped hole, and the spring and the conductor are sequentially installed in the stepped hole.

[0013] Furthermore, the motor spindle is provided with a stepped hole, and the spring and the conductor are sequentially installed in the stepped hole.

[0014] Furthermore, the conductor is a carbon brush.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. This utility model provides a spring and a conductor on the motor spindle or on the end cover. Both methods ensure real-time contact between the conductor and the motor spindle, resulting in good contact performance. This can eliminate shaft current in oil-cooled motors, protect the conductor, and prevent oil from dripping onto the conductor and affecting its conductivity.

[0017] 2. The shaft current elimination structure of the oil-cooled motor of this utility model has a simple overall structure, good manufacturability, convenient maintenance, and low cost. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the first embodiment of the shaft current elimination structure for an oil-cooled motor according to the present invention;

[0019] Figure 2 This is a schematic diagram of the second embodiment of the shaft current elimination structure for an oil-cooled motor according to the present invention.

[0020] In the diagram: 1. Motor spindle; 2. Oil seal; 3. Conductor; 4. Spring; 5. End cover; 6. Housing. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0022] First embodiment:

[0023] See Figure 1This embodiment discloses a shaft current elimination structure for an oil-cooled motor, including a motor spindle 1, an end cover 5, and a housing 6. A spring 4 and a conductor 3 are mounted on the end cover 5. Specifically, the end cover 5 has stepped holes, and the spring 4 and conductor 3 are sequentially installed in the stepped holes. Preferably, the conductor 3 is a carbon brush, but a carbon rod can also be used. The conductor 3 is in contact with the end cover 5, and the end of the conductor 3 away from the spring 4 is in contact with the shaft head of the motor spindle 1. Further, this embodiment also includes an oil seal 2. By sequentially inserting the spring 4 and conductor 3 into the stepped holes of the end cover 5, then pressing the oil seal 2 in place, and then installing the end cover 5 onto the housing 6, the conductor 3 contacts the shaft head of the motor spindle 1, forming a circuit, thereby achieving conductivity between the motor spindle 1 and the housing 5 and drawing out the shaft current on the rotor.

[0024] Second embodiment:

[0025] See Figure 2 This embodiment discloses a shaft current elimination structure for an oil-cooled motor, including a motor spindle 1, an end cover 5, and a housing 6. A spring 4 and a conductor 3 are mounted on the motor spindle 1. Specifically, the motor spindle 1 has a stepped hole, and the spring 4 and conductor 3 are sequentially installed within the stepped hole. Preferably, the conductor 3 is a carbon brush, but a carbon rod can also be used. The conductor 3 is in contact with the motor spindle 1, and the end of the conductor 3 away from the spring 4 contacts the shaft end of the end cover 5. Further, this embodiment also includes an oil seal 2. By sequentially inserting the spring 4 and conductor 3 into the stepped hole of the motor spindle 1, then pressing in the oil seal 2, and finally installing the end cover 5 onto the housing 6, the conductor 3 contacts the shaft end of the end cover 5, forming a circuit, thereby achieving conductivity between the motor spindle 1 and the housing 6 and drawing out the shaft current on the rotor.

[0026] It should be noted that the positions of conductor 3, spring 4 and oil seal 2 in the diagram are not limited to those shown in the diagram and can be adjusted according to actual installation needs;

[0027] The contact between the conductor 3 and the motor spindle 1 shown in the figure is not limited to the situation shown in the figure, and can be adjusted according to the actual situation;

[0028] The conductor 3 shown in the figure is not limited to carbon brushes, carbon rods, etc. Other conductive materials can also be selected, and adjustments can be made according to the actual situation.

[0029] This invention provides a spring 4 and a conductor 3 on the motor spindle 1, or on the end cover 5. Both methods ensure real-time contact between the conductor 3 and the motor spindle 1, resulting in good contact performance. This eliminates shaft current in oil-cooled motors, protects the conductor, and prevents oil from dripping onto the conductor, thus maintaining conductivity.

[0030] Compared with existing technical solutions, this shaft current elimination scheme has a simple structure, good manufacturability, convenient maintenance, and low cost.

[0031] It should be noted that this utility model is described in the context of eliminating motor shaft current, but in actual application, it can be applied as needed and is not limited to the field of eliminating motor shaft current.

[0032] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0033] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A shaft current elimination structure for an oil-cooled motor, characterized in that: The device includes a motor spindle (1), an end cover (5), a spring (4), a conductor (3), and a housing (6). The end cover (5) has a stepped hole. The spring (4) and the conductor (3) are installed in the stepped hole in sequence. The conductor (3) is in contact with the end cover (5) and conducts electricity. The end of the conductor (3) away from the spring (4) is in contact with the shaft head of the motor spindle (1). The device also includes an oil seal (2), which is press-fitted into the overlapping part of the stepped holes of the motor spindle (1) and the end cover (5).

2. The shaft current elimination structure for an oil-cooled motor according to claim 1, characterized in that: The conductor (3) is in contact with the motor spindle (1) and conducts electricity. The end of the conductor (3) away from the spring (4) is in contact with the end cap (5) shaft head.

3. The shaft current elimination structure for an oil-cooled motor according to claim 2, characterized in that: The motor spindle (1) is provided with a stepped hole, and the spring (4) and the conductor (3) are installed in the stepped hole in sequence.

4. The shaft current elimination structure for an oil-cooled motor according to claim 1 or 2, characterized in that: The conductor (3) is a carbon brush.

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