Axle electric filter, preparation method, new energy automobile half axle and vehicle

Abstract

The invention discloses an axle electric filter, a preparation method, a new energy automobile half axle and a vehicle, and belongs to the technical field of filters, the axle electric filter comprises a ferrite magnetic ring and a rubber shell wrapping the ferrite magnetic ring, and the ferrite magnetic ring can be arranged on an axle conductor in a sleeving mode through the rubber shell; the ferrite magnetic ring comprises the following components in percentage by weight: 64.3 to 68.2 percent of Fe2O3, 19.5 to 24.6 percent of Mn3O4, 0.03 to 0.63 percent of auxiliary components and the balance of ZnO, wherein the auxiliary components are used for improving the impedance of the ferrite magnetic ring. Electromagnetic coupling is generated between the shaft current signal and the ferrite magnetic ring, so that the shaft current signal changes under the action of the ferrite magnetic ring. When a vehicle runs, a part of shaft current energy is transferred into the ferrite magnetic ring and is consumed or reflected under the impedance action of the ferrite magnetic ring, so that the strength of a shaft current signal is effectively reduced, the purpose of suppressing shaft current interference is achieved, normal operation of each part of the vehicle is ensured, the energy efficiency is improved, and the service life of the vehicle is prolonged. And potential risks possibly caused by magnetic field interference are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of filters, and in particular to an axle electric filter, a preparation method, a new energy vehicle half-axle and a vehicle. Background Art

[0002] New energy vehicles, especially electric vehicles, contain a large number of electromagnetic devices and systems, such as motors, batteries, sensors, etc. These devices and systems may generate electromagnetic interference when working. If the electromagnetic interference of certain components or systems is not properly shielded, it may affect the performance and safety of the vehicle. The generation of electromagnetic interference includes three basic elements: interference source, transmission path and sensitive equipment. In actual work, only one of them needs to be suppressed to effectively reduce the electromagnetic interference problem. At present, a lot of analysis and research on the suppression of conducted electromagnetic interference has been carried out at home and abroad. There are two main suppression methods, one is to shield and limit the emission intensity of the interference source; the other is to study the propagation path of electromagnetic interference and block it.

[0003] The main sources of shaft current in vehicles are as follows: factors such as motor lamination structure and lamination process lead to unbalanced magnetic circuit; variable frequency PWM pulse width modulation generates high-order harmonics, which causes electromagnetic induction to form common mode voltage. The high-frequency oscillation of the common mode voltage and the capacitive coupling of the rotor generate a pulse voltage from the rotor shaft to the ground. After the voltage breaks through the oil film, a ground loop is formed to generate high-density shaft current.

[0004] New energy vehicles will generate shaft current due to motor operation, electrostatic induction, common mode voltage, stray capacitance, etc. The shaft current passes through the loop formed by the shaft, bearing and bottom plate, generating electro-corrosion pitting or washboard-like burn marks on the journal and bearing or causing the rolling bearing to overheat and burn, thus significantly affecting the service life of the bearing. Shaft current is not only harmful to the bearing, but also to the motor and even the entire vehicle. For example, shaft current will increase the wear of the bearing and reduce the lubrication performance; affect the efficiency of the motor and cause electromagnetic interference; shorten the life of the vehicle's components and affect driving safety. Therefore, the shaft current must be suppressed and filtered.

[0005] In order to prevent the adverse effects of shaft current on motor bearings, grease is currently used as a lubricant for new energy vehicle drive motor bearings. The grease has good high and low temperature performance and shock absorption and wear resistance, and has a conductive function to reduce the accumulation of shaft voltage, thereby reducing the generation of shaft current. However, this type of grease can only reduce a part of the shaft current, and in the long run it will also affect the service life of the bearing. Relatively standardized motor manufacturers will use insulating bearings and insulating end covers to prevent the adverse effects of shaft currents during the manufacturing process of the motor bearing system. However, this type of sealing measure greatly reduces the wear resistance at high speeds, shortens the service life of the bearing, and has a high production cost. There are also bypass measures to increase the annular drainage carbon brush, but the premise is that there is space for the carbon brush when the motor is running, which will not affect the overall assembly space of the motor, but this measure involves the purchase of annular brushes and the matching relationship with the bearing cover, and the cost is relatively high. Summary of the invention

[0006] In view of the problems existing in the prior art, the present invention provides an axle electric filter, a preparation method, a new energy vehicle half-axle and a vehicle. The axle electric filter can weaken or remove the axle current interference in the vehicle, improve the NVH of the vehicle, and ensure the normal operation of various components of the vehicle.

[0007] The present invention is achieved through the following technical solutions: In a first aspect, the present application provides an axial electric filter, comprising a ferrite magnetic ring and a rubber shell coated on the ferrite magnetic ring, wherein the ferrite magnetic ring can be sleeved on the axial conductor through the rubber shell; The ferrite magnetic ring reduces the intensity of the shaft current signal in the shaft conductor under the action of impedance, thereby suppressing the interference of the shaft current signal.

[0008] Preferably, the ferrite ring includes, by mass percentage, 64.3-68.2wt% of Fe2O3, 19.5-24.6wt% of Mn3O4, 0.03-0.63wt% of auxiliary components and the balance of ZnO, wherein the auxiliary components are used to increase the impedance of the ferrite ring.

[0009] Preferably, the auxiliary component includes at least one of 0.03-0.07wt% NiO, 0.41-0.63wt% Co3O4 and 0.25-0.33wt% SiO2.

[0010] Preferably, a plurality of buffer grooves are evenly distributed on the circumference of the inner ring wall of the rubber housing, and the buffer grooves axially penetrate the rubber housing.

[0011] Preferably, a ring sleeve is formed at the end of the rubber housing to form a stable connection between the axial electric filter and the axial conductor.

[0012] Preferably, the weight of the axial electric filter is (490±3) g.

[0013] In a second aspect, the present application provides a method for preparing an axial electric filter, comprising the following steps: Step 1, sintering the magnetic ring blank at 1240° C. to 1300° C. for 5 h to 6 h to obtain a ferrite magnetic ring; Step 2: Cover the surface of the ferrite magnetic ring with a fully sealed rubber shell to obtain an axial electric filter.

[0014] 8. The method for preparing an axial electric filter according to claim 7, characterized in that the preparation method of the ferrite magnetic ring in step 1 is as follows: S100, Fe2O 3、 Mn3O4 and ZnO powders are mixed and ball-milled, and dried to obtain a mixture; S200, pre-burning the mixed material at 850°C-950°C to obtain a pre-burned material; S300, mixing the pre-sintered material with the auxiliary components, ball milling and drying, selecting particles with a mesh size of 60-120 after granulation, and pressing to obtain a magnetic ring blank; S400, sintering the magnetic ring blank at 1240°C~1300°C for 5h~6h to obtain a ferrite magnetic ring.

[0015] In a third aspect, the present application provides a new energy vehicle half-axle, on which the shaft electric filter according to any one of claims 1-6 is arranged.

[0016] In a fourth aspect, the present application provides an electric drive vehicle, including the shaft electric filter.

[0017] Compared with the prior art, the present invention has the following beneficial technical effects: A shaft electric filter of the present application is installed on the shaft conductor through a rubber shell, and electromagnetic coupling will be generated between the shaft current signal flowing through the shaft conductor and the ferrite ring. This coupling effect causes the shaft current signal to change under the action of the ferrite ring. A part of the shaft current energy will be transferred to the ferrite ring, and will be consumed or reflected under the impedance of the ferrite ring, thereby effectively reducing the strength of the shaft current signal, achieving the purpose of suppressing shaft current interference, helping to ensure the normal operation of various components of the vehicle, improving energy efficiency, and reducing potential risks caused by magnetic field interference; secondly, the shaft electric filter is installed on the shaft conductor by a rubber shell, and the buffer groove forms a deformation space. The rubber shell can effectively absorb the vibration of the half shaft and protect the normal operation of the shaft electric filter. At the same time, the sealing design of the rubber shell also has the functions of moisture-proof, mildew-proof, high temperature resistance, etc. The filter is integrated with the dynamic vibration absorber to form the shaft electric filter, which can not only meet the vibration reduction function of the traditional vibration absorber, but also effectively suppress the shaft current interference. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 It is a structural diagram of the upper end of the axial electric filter of the present invention; Figure 2 This is a structural diagram of the lower end of the axial electric filter of the present invention.

[0020] In the figure: 1. rubber shell; 2. ring sleeve; 3. groove. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution 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 part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0022] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0023] A shaft electric filter comprises a ferrite magnetic ring and a rubber shell covering the ferrite magnetic ring, wherein the ferrite magnetic ring can be sleeved on the shaft conductor through the rubber shell; The ferrite magnetic ring has the characteristics of high magnetic permeability and high impedance, and can reduce the intensity of the shaft current signal in the shaft conductor, thereby suppressing the interference of the shaft current signal.

[0024] The axial electric filter is installed on the axial conductor through a rubber housing, and the electromagnetic coupling between the ferrite ring and the axial conductor is the key. When an axial current flows through the axial conductor, a magnetic field is generated around it, and this magnetic field will induce electromagnetic coupling on the ferrite ring. This coupling enables part of the energy of the axial current to be transferred to the ferrite ring. The ferrite ring has a certain impedance, which means that when the current tries to pass through it, it will encounter resistance. Therefore, the axial current energy transferred to the ferrite ring will be consumed (converted into heat energy) or reflected back to the original circuit under the action of impedance. In this way, the axial current signal that may originally interfere with other electronic equipment is effectively weakened.

[0025] The magnetic field generated by the shaft current may interfere with other electronic devices in the vehicle, such as sensors, controllers, etc. In the vehicle system, any uncontrolled current or magnetic field may pose a safety hazard. The filter can reduce this magnetic field interference by suppressing the strength of the current signal, reducing the risk of system failure or misoperation caused by interference. By effectively suppressing the shaft current, the filter helps prevent vehicle component failure or performance degradation caused by current interference, thereby improving the overall safety of the vehicle.

[0026] In some embodiments, a plurality of buffer grooves 3 are evenly distributed on the circumference of the inner ring wall of the rubber housing 1 , and the buffer grooves axially penetrate the entire rubber housing.

[0027] The shaft electric filter is installed on the shaft conductor using a rubber shell, and the buffer groove forms a deformation space. The rubber shell can effectively absorb the vibration of the half shaft and protect the normal operation of the shaft electric filter. At the same time, the sealing design of the rubber shell also has the functions of moisture-proof, mildew-proof, and high temperature resistance. In some embodiments, a ring sleeve 2 is formed at the end of the rubber housing, and the ring sleeve 2 is used to be sleeved on the shaft conductor, and a fixing structure is provided on the ring sleeve to form a stable connection between the filter and the shaft conductor.

[0028] The fixing device is a hoop or a rope.

[0029] In some embodiments, the weight of the filter is related to the characteristics of the semi-axle itself, and the mass, length, diameter and other parameters of the semi-axle must be determined first. The larger the mass of the semi-axle, the more counterweight is required to balance the vibration generated by the semi-axle during rotation. The material of the semi-axle also has an impact. Different materials have different densities and elastic moduli, which will lead to differences in vibration characteristics, thereby affecting the choice of counterweight weight.

[0030] When the half shaft rotates, it is easy to vibrate due to its own imbalance and other factors. Counterweight can change the vibration characteristics of the half shaft. Reasonable counterweight can adjust the natural frequency of the half shaft to avoid strong vibration and noise due to resonance during vehicle operation. For example, when the vehicle is running in a specific speed range, if the half shaft frequency resonates with road excitation, engine excitation, etc., it will cause body shaking and obvious noise. Counterweight can alleviate this situation, thereby improving NVH performance.

[0031] NVH is the abbreviation of noise, vibration and harshness. It is a comprehensive issue to measure the quality of automobile manufacturing and directly affects the experience of car users.

[0032] As a component that supports the motor rotor and rotates at ultra-high speed with the motor rotor, the bearing works under unavoidable harsh conditions such as impact loads and high-speed friction, which are prone to NVH and reliability problems. In addition, the rotor shaft current produces electro-corrosion pits, which further amplify NVH and reliability problems. By designing the shaft electric filter to an appropriate weight, the mass distribution of the half shaft can also be adjusted to achieve a better balance state while satisfying the shaft current suppression. When the half shaft is balanced, the periodic vibration caused by imbalance during rotation will be significantly weakened, thereby reducing the overall vibration level of the vehicle and improving NVH.

[0033] Based on the above-mentioned axial electric filter, the present application also provides a method for preparing the axial electric filter, comprising the following steps: Step 1, sintering the magnetic ring blank at 1240° C. to 1300° C. for 5 h to 6 h to obtain a ferrite magnetic ring; In terms of mass percentage, the magnetic ring blank includes 64.3-68.2wt% of Fe2O3, 19.5-24.6wt% of Mn3O4, 0.03-0.63wt% of auxiliary components and the balance of ZnO, wherein the auxiliary components are used to increase the impedance of the ferrite magnetic ring; Step 2: Cover the surface of the ferrite magnetic ring with a fully sealed rubber shell to obtain an axial electric filter.

[0034] The axial electric filter adopts a combination of sintering and injection molding processes. The axial electric filter can be prepared in two steps. The magnetic ring blank is sintered in the temperature range of 1240℃~1300℃ and lasts for 5h~6h. High-temperature sintering helps the raw materials to fully react and form a stable crystal structure, thereby improving the magnetic properties and mechanical strength of the ferrite magnetic ring. At the same time, this temperature range and time control also avoids abnormal grain growth or material overburning caused by excessively high temperatures or excessively long times, thereby ensuring the performance stability of the magnetic ring.

[0035] In the raw material ratio of the magnetic ring blank, Fe2O3, Mn3O4 and ZnO are the main components, and a small amount of auxiliary components are added, which has a significant effect on improving the impedance of the ferrite magnetic ring. This helps to improve the electromagnetic performance of the filter and improve its filtering effect at high frequencies.

[0036] The fully sealed rubber shell covering the surface of the ferrite magnetic ring not only provides physical protection for the magnetic ring to prevent it from mechanical damage or environmental erosion during use, but also ensures that the electrical performance of the magnetic ring is not interfered with by the outside world. The fully sealed design also helps to improve the reliability and service life of the filter, especially in harsh working environments, such as high temperature, high humidity or corrosive environments, this protection is particularly important.

[0037] In some embodiments, the auxiliary component includes 0.03~0.07wt% NiO, 0.41~0.63wt% Co3O4 or 0.25~0.33wt% SiO2; the auxiliary component can effectively improve the impedance performance of the ferrite ring, while improving the magnetic permeability of the ferrite ring and reducing the loss.

[0038] As the best embodiment of the present application, the preparation method of the ferrite magnetic ring is as follows: S100, Fe2O 3、 Mn3O4 and ZnO powders were mixed and ball-milled, and then dried and filtered to obtain a 60-mesh mixture; S200, pre-calculate the 60-mesh mixed material at 850°C-950°C, and obtain the pre-calcined material after cooling.

[0039] S300, mixing the pre-sintered material with the auxiliary components, and then ball-milling and drying. After granulation, selecting particles with a mesh size of 60 to 120, and pressing to obtain a magnetic ring blank.

[0040] S400, sintering the magnetic ring blank at 1240°C~1300°C for 5h~6h to obtain a ferrite magnetic ring.

[0041] As the best embodiment of the present application, a rubber shell is integrally formed on the ferrite magnetic ring by injection molding, and buffer grooves are formed on the inner ring wall of the rubber shell at intervals in the circumferential direction. The full strip corrugation is adopted, so that the axle can be better tightly wrapped with its own traction performance and elasticity to avoid sliding, and at the same time avoid damage to the magnetic core due to vibration.

[0042] Example 1 A method for preparing an axial electric filter comprises the following steps: Step 1, by mass percentage, 65.71wt% of Fe2O3, 20.66wt% of Mn3O4 and 13.63wt% of ZnO are mixed to obtain a mixture A; Step 2, ball milling is performed once according to the mass ratio of mixed material A: zirconium beads: deionized water = 1:6:1, the ball milling time is 4 hours, the rotation speed is 400r / min, and then drying is performed to obtain a primary ball mill material; Step 3: Pass the primary ball mill material through a 60-mesh sieve, put it into a crucible, put it into a box furnace for pre-burning at 950°C, keep it warm for 2 hours, and then cool it naturally to obtain a pre-burned material.

[0043] Step 4: Use secondary addition technology to add auxiliary components to the above pre-burned material and mix them evenly to obtain a mixture B, which includes auxiliary components of 0.05wt% NiO, 0.5wt% Co3O4, and 0.3wt% SiO2 powder.

[0044] Step 5, according to the mass ratio, the mixture B: zirconium beads: deionized water = 1:6:1 ratio is subjected to secondary ball milling, the ball milling time is 6 hours, the rotation speed is 400r / min, and then drying is performed to obtain secondary ball milling material; Step 6: Pass the secondary ball-milled material through a 120-mesh sieve, add a 13 wt% polyvinyl alcohol aqueous solution for granulation, select 60-120 mesh granules for compression molding, and obtain a Ø60*Ø32*47 (mm) magnetic ring blank.

[0045] Step 7: Sinter the magnetic ring blank at 1240° C. in a balanced oxygen partial pressure atmosphere for 5.5 hours to obtain a ferrite magnetic ring.

[0046] Step 8: Use injection molding to form a rubber shell on the surface of the ferrite ring to obtain an axial electric filter.

[0047] The Ls value of the sample was tested at 100kHz using an E4980AL inductance tester, and the initial magnetic permeability (μ i ), the Z value of the sample was tested at 15MHz, 18MHz, and 30MHz using a 3535 impedance tester. The results are shown in Table 1.

[0048] Comparative Examples 1-3 of Example 1 On the basis of Example 1, the addition amount of its main components was changed, Fe2O3 was decreased by every 0.3wt% addition amount, and ZnO was increased by every 0.3wt% addition amount, to obtain three groups of comparative examples, and the preparation process was the same as that of Example 1.

[0049] Table 1

[0050] Example 2 A method for preparing an axial electric filter comprises the following steps: Step 1, by mass percentage, 66.18 wt% of Fe2O3, 20.85 wt% of Mn3O4 and 12.97 wt% of ZnO are mixed to obtain a mixture A; Step 2, ball milling is performed once according to the mass ratio of mixed material A: zirconium beads: deionized water = 1:6:1, the ball milling time is 4 hours, the rotation speed is 400r / min, and then drying is performed to obtain a primary ball mill material; Step 3: Pass the primary ball mill material through a 60-mesh sieve, put it into a crucible, put it into a box furnace for pre-burning at 880°C, keep it warm for 2 hours, and then cool it naturally to obtain a pre-burned material.

[0051] Step 4: using secondary addition technology, add auxiliary components to the above pre-burned material and mix them evenly to obtain a mixture B, wherein the auxiliary components include 0.5wt% NiO and 0.83wt% Co3O4.

[0052] Step 5, according to the mass ratio, the mixture B: zirconium beads: deionized water = 1:6:1 ratio is subjected to secondary ball milling, the ball milling time is 6 hours, the rotation speed is 400r / min, and then drying is performed to obtain secondary ball milling material; Step 6: Pass the secondary ball-milled material through a 120-mesh sieve, add a 13 wt% polyvinyl alcohol aqueous solution for granulation, select 60-120 mesh granules for compression molding, and obtain a Ø60*Ø32*47 (mm) magnetic ring blank.

[0053] Step 7: sinter the magnetic ring blank at 1240° C. and 1260° C. in an atmosphere with a balanced oxygen partial pressure for 5.5 hours to obtain a ferrite magnetic ring.

[0054] Step 8: Use injection molding to form a rubber shell on the surface of the ferrite ring to obtain an axial electric filter.

[0055] The Ls value of the sample was tested at 100kHz using an E4980AL inductance tester, and the initial magnetic permeability (μ i ), the Z value of the sample was tested at 15MHz, 18MHz, and 30MHz using a 3535 impedance tester. The results are shown in Table 2.

[0056] Comparative Examples 4-6 of Example 2 On the basis of Example 2, the addition amount of the auxiliary components was changed, and the addition amount of NiO was increased by 0.2wt%. The preparation method was the same as that of Example 2, and three groups of comparative examples were obtained.

[0057] Table 2

[0058] Example 3 A method for preparing an axial electric filter comprises the following steps: Step 1, by mass percentage, 66.58 wt% of Fe2O3, 21.75 wt% of Mn3O4 and 11.67 wt% of ZnO are mixed to obtain a mixture A; Step 2, ball milling is performed once according to the mass ratio of mixed material A: zirconium beads: deionized water = 1:6:1, the ball milling time is 4 hours, the rotation speed is 400r / min, and then drying is performed to obtain a primary ball mill material; Step 3: Pass the primary ball mill material through a 60-mesh sieve, put it into a crucible, put it into a box furnace for pre-burning at 900° C., keep it warm for 2 hours, and then cool it naturally to obtain a pre-burned material.

[0059] Step 4: using secondary addition technology, add auxiliary components to the above pre-burned material and mix them evenly to obtain a mixture B, wherein the auxiliary components include 0.83 wt% of Co3O4 powder.

[0060] Step 5, according to the mass ratio, the mixture B: zirconium beads: deionized water = 1:6:1 ratio is subjected to secondary ball milling, the ball milling time is 6 hours, the rotation speed is 400r / min, and then drying is performed to obtain secondary ball milling material; Step 6: Pass the secondary ball-milled material through a 120-mesh sieve, add a 13 wt% polyvinyl alcohol aqueous solution for granulation, select 60-120 mesh granules for compression molding, and obtain a Ø60*Ø32*47 (mm) magnetic ring blank.

[0061] Step 7: Sinter the magnetic ring blank at 1260° C. in a balanced oxygen partial pressure atmosphere for 5.5 hours to obtain a ferrite magnetic ring.

[0062] Step 8: Use injection molding to form a rubber shell on the surface of the ferrite ring to obtain an axial electric filter.

[0063] The Ls value of the sample was tested at 100kHz using an E4980AL inductance tester, and the initial magnetic permeability (μ i ), the Z value of the sample was tested at 15MHz, 18MHz, and 30MHz using a 3535 impedance tester. The results are shown in Table 3.

[0064] Table 3

[0065] By comparing Example 2 with Example 3, on the basis of Example 2, only the auxiliary component NiO is removed, and the pre-firing temperature is increased by 20° C., and the μi value and impedance (Z) are significantly improved.

[0066] Example 4 The sintering temperature was increased on the basis of Example 3 to obtain two groups of test data. The results are shown in Table 4.

[0067] Table 4

[0068] It can be seen from the table that the increase of sintering temperature has a key influence on changing the magnetic permeability while ensuring the impedance. At 1280℃, the initial magnetic permeability is ≥3000, 1300℃ is optimal, and the impedance still remains ≥370Ω at 30MHz.

[0069] Example 5 According to the preparation method of Example 4, a ferrite magnetic ring for a new energy vehicle axle electric filter with a size of Ø60*32*47 (mm) was manufactured by adopting a 1300° C. sintering process, and a fully sealed rubber housing was made for the ferrite magnetic ring.

[0070] The rubber shell of the inner diameter part is made of full strip corrugated structure. The Ls value of the sample is tested at 100kHz using E4980AL inductance tester to calculate the initial magnetic permeability (μ i ), the Z value of the sample was tested at 15MHz, 18MHz, and 30MHz using a 3535 impedance tester, and combined with the installation conditions on the automotive half-axle, the results are shown in Table 5.

[0071] Comparative Example of Example 5 According to the preparation method of Example 4, a ferrite magnetic ring for a new energy vehicle axle electric filter with a size of Ø60*32*47 (mm) was manufactured by adopting a 1300° C. sintering process, and a fully sealed rubber housing was made for the ferrite magnetic ring.

[0072] The rubber shell of the inner diameter part is made of full strip corrugated structure. The Ls value of the sample was tested at 100kHz using E4980AL inductance tester, and the Z value of the sample was tested at 15MHz, 18MHz, and 30MHz using 3535 impedance tester. Combined with the installation on the half shaft of the car, the results are shown in Table 5.

[0073]

[0074] Example 5 A shaft, on which the shaft electric filter is installed. The shaft is a half shaft of a new energy vehicle. The shaft electric filter is used to suppress the shaft current signal flowing through the half shaft, weaken or eliminate the shaft current interference in the vehicle, improve the NVH of the vehicle, and ensure the normal operation of various components of the vehicle.

[0075] A vehicle comprises the shaft and / or shaft electric filter described in Example 5.

[0076] The vehicle is a new energy electric vehicle, which includes pure electric vehicles, hybrid vehicles, and extended-range vehicles.

[0077] The application of this shaft current filter in new energy vehicles can not only effectively reduce the shaft current interference in the vehicle, but also has a shock absorption function, improves the NVH (Noise, Vibration, Harshness) of the vehicle, helps to ensure the normal operation of various components of the vehicle, improve energy efficiency, and reduce potential risks caused by magnetic field interference. Ensuring the normal operation of various components of the vehicle guarantees the safety and reliability of new energy vehicles, and provides important guarantees for the safety and reliability of new energy vehicles.

[0078] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. An axial electric filter, characterized in that: It includes a ferrite magnetic ring and a rubber shell covering the ferrite magnetic ring, and the ferrite magnetic ring can be sleeved on the shaft conductor through the rubber shell; The ferrite magnetic ring reduces the intensity of the shaft current signal in the shaft conductor under the action of impedance, thereby suppressing the interference of the shaft current signal.

2. The axial electric filter according to claim 1, characterized in that: Calculated by mass percentage, the ferrite magnetic ring includes 64.3-68.2wt% of Fe2O3, 19.5-24.6wt% of Mn3O4, 0.03-0.63wt% of auxiliary components and the balance of ZnO, wherein the auxiliary components are used to increase the impedance of the ferrite magnetic ring.

3. The axial electric filter according to claim 2, characterized in that: The auxiliary component includes at least one of 0.03-0.07wt% NiO, 0.41-0.63wt% Co3O4 and 0.25-0.33wt% SiO2.

4. The axial electric filter according to claim 1, characterized in that: A plurality of buffer grooves are evenly distributed on the circumference of the inner ring wall of the rubber housing, and the buffer grooves axially penetrate the rubber housing.

5. The axial electric filter according to claim 1, characterized in that: The end of the rubber housing is formed with a ring sleeve for forming a stable connection between the axial electric filter and the axial conductor.

6. The axial electric filter according to claim 1, characterized in that: The weight of the axial electric filter is (490±3) g.

7. A method for preparing an axial electric filter according to any one of claims 1 to 6, characterized in that: The following steps are involved: Step 1, sintering the magnetic ring blank at 1240° C. to 1300° C. for 5 h to 6 h to obtain a ferrite magnetic ring; Step 2: Cover the surface of the ferrite magnetic ring with a fully sealed rubber shell to obtain an axial electric filter.

8. The method for preparing an axial electric filter according to claim 7, characterized in that: The preparation method of the ferrite magnetic ring described in step 1 is as follows: S100, Fe2O 3、 Mn3O4 and ZnO powders are mixed and ball-milled, and dried to obtain a mixture; S200, pre-burning the mixed material at 850°C-950°C to obtain a pre-burned material; S300, mixing the pre-sintered material with the auxiliary components, ball milling and drying, selecting particles with a mesh size of 60-120 after granulation, and pressing to obtain a magnetic ring blank; S400, sintering the magnetic ring blank at 1240°C~1300°C for 5h~6h to obtain a ferrite magnetic ring.

9. A new energy vehicle half shaft, characterized in that: The new energy vehicle half-axle is provided with an axis electric filter as described in any one of claims 1-6.

10. An electric drive vehicle, characterized in that: The invention comprises the axial electric filter as described in any one of claims 1 to 6.

Images