Shaft electric corrosion inhibition assembly and electric driving system
The carbon rod and the elastic parts are directly electrically connected to the circuit board or case, and the brush braid line is cancelled, which solves the problems of low integration and high cost of carbon brush assembly structure, and realizes effective axial electrocorrosion suppression and complex contour processing.
Patent Information
- Application Number
- CN202421500122.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-27
- Publication Date
- 2025-09-02
- Estimated Expiration
- 2034-06-27
AI Technical Summary
In the prior art, the structural integration of carbon brush components is low and the cost is high, so the problem of electrocorrosion cannot be effectively suppressed.
The carbon rod and the elastic member are directly electrically connected to the circuit board or case, and the brushing wire is cancelled. The elastic member provides thrust to make the carbon rod contact the shaft, leads the shaft current, and uses the capacitor on the circuit board to reduce the bearing voltage to avoid breakdown.
It improves the integration of carbon brush components, reduces costs, and effectively suppresses axial corrosion, expands the application scenarios for processing complex contours.
Smart Images
Figure CN223297180U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of conductive structures, in particular to a shaft electrical corrosion suppression component and an electric drive system. Background Art
[0002] Currently, most automotive motors use PWM (Pulse Width Modulation) inverters with IGBTs (Insulated Gate Bipolar Transistors) as their power devices. Driven by a sinusoidal power supply and internal motor factors, shaft voltage and current are unavoidable. Excessive shaft current can cause electrical corrosion in bearings. When the bearing voltage between the inner and outer raceways rises to a certain level, exceeding the lubricant film threshold voltage, a breakdown discharge occurs. The resulting short-circuit current quickly generates significant heat, melting the metal near the breakdown point. This leads to increasingly poor motor bearing performance and shortens bearing life. Long-term shaft current can compromise reliable motor operation. Shaft corrosion suppression components (e.g., carbon brushes) are often used to "conduct" the shaft current and address the problem of bearing corrosion.
[0003] In related technologies, coil springs and brush braids are usually embedded in the carbon powder before the carbon rod is pressed into shape. After high-temperature baking, the carbon brush assembly is demolded to obtain the ends of the coil springs and brush braids, which are then welded to the hardware. This results in low structural integration and high cost. Utility Model Content
[0004] The main purpose of the utility model is to provide a shaft electrical corrosion suppression component and an electric drive system, aiming to improve the integration of the carbon brush assembly and reduce the cost.
[0005] To achieve the above objectives, the present invention provides a shaft electrical corrosion suppression assembly, comprising:
[0006] circuit boards;
[0007] A carbon brush assembly, comprising:
[0008] Carbon rods;
[0009] An elastic member, one end of which is electrically connected to the end of the carbon rod and keeps the carbon rod moving in a preset direction to provide thrust; the carbon rod is electrically connected to the circuit board through the elastic member, or is used to connect to the housing.
[0010] In one embodiment, the elastic member is a belt-shaped elastic member.
[0011] In one embodiment, the elastic band includes a plurality of V-shaped elastic pieces connected end to end.
[0012] In one embodiment, one end of the elastic member is detachably connected to the end of the carbon rod.
[0013] In one embodiment, one end of the elastic member is connected to the end of the carbon rod through a snap-fit structure.
[0014] In one embodiment, the snap-fit structure includes a snap-fit and a slot, one end of the elastic member and one of the ends of the carbon rod are provided with the snap-fit, and the other end is provided with the slot, and the snap-fit is engaged with the slot.
[0015] In one embodiment, one end of the elastic member is welded to the end of the carbon rod.
[0016] In one embodiment, a contoured groove is provided at the end of the carbon rod, and one end of the elastic member is installed in the contoured groove.
[0017] In one embodiment, the end of the elastic member away from the carbon rod is used for electrically connecting to a circuit board, or for connecting to a housing.
[0018] In one embodiment, the end of the elastic member away from the carbon rod is mounted on the circuit board using surface mounting technology.
[0019] The present invention also provides an electric drive system, comprising:
[0020] chassis;
[0021] a shaft disposed in the housing;
[0022] In the shaft electro-corrosion suppression assembly as described above, the carbon rod is electrically connected to the circuit board or to the housing through the elastic member. When the elastic member provides the carbon rod with a thrust force to move in a preset direction to drive the carbon rod toward the shaft, the contact surface of the carbon rod contacts the circumferential surface and / or end face of the shaft.
[0023] By directly electrically connecting one end of an elastic member to the end of a carbon rod, the present invention allows the carbon rod to be directly electrically connected to a circuit board or a housing through the elastic member, thereby conducting shaft current and eliminating the need for brush braids. This improves the integration of the carbon brush assembly and reduces costs. Furthermore, the carbon rod does not need to be pre-embedded before being pressed and formed, and is not restricted by internal structural components during machining, allowing for the processing of more complex contours and expanding application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.
[0025] Figure 1 This is a structural schematic diagram of an embodiment of a carbon brush assembly provided by the present utility model.
[0026] Description of Figure Numbers:
[0027] 10. Carbon brush assembly; 11. Carbon rod; 111. End; 112. Profile groove; 12. Elastic member; 121. V-shaped spring.
[0028] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION
[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.
[0030] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indications will also change accordingly.
[0031] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of such features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme in which A and B are satisfied at the same time. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.
[0032] Currently, most automotive motors use PWM (Pulse Width Modulation) inverters with IGBTs (Insulated Gate Bipolar Transistors) as their power devices. Driven by a sinusoidal power supply and internal motor factors, shaft voltage and current are unavoidable. Excessive shaft current can cause electrical corrosion in bearings. When the bearing voltage between the inner and outer raceways rises to a certain level, exceeding the lubricant film threshold voltage, a breakdown discharge occurs. The resulting short-circuit current quickly generates significant heat, melting the metal near the breakdown point. This leads to increasingly poor motor bearing performance and shortens bearing life. Long-term shaft current can compromise reliable motor operation. Shaft corrosion suppression components (e.g., carbon brushes) are often used to "conduct" the shaft current and address the problem of bearing corrosion.
[0033] In related technologies, coil springs and brush braids are usually embedded in the carbon powder before the carbon rod is pressed into shape. After high-temperature baking, the carbon brush assembly is demolded to obtain the ends of the coil springs and brush braids, which are then welded to the hardware. This results in low structural integration and high cost.
[0034] Based on the above problems, the present invention proposes a shaft electro-corrosion suppression assembly, which aims to improve the integration of carbon brush assemblies and reduce costs.
[0035] See also Figure 1 In one embodiment of the present invention, the shaft electro-corrosion suppression assembly includes a circuit board and a carbon brush assembly 10, and the carbon brush assembly 10 includes a carbon rod 11 and an elastic member 12; one end of the elastic member 12 is electrically connected to the end 111 of the carbon rod, and keeps the carbon rod 11 moving in a preset direction to provide thrust; the carbon rod 11 is electrically connected to the circuit board through the elastic member 12, or is used to connect to the casing.
[0036] The technical solution of the present invention electrically connects one end of the elastic member 12 directly to the end 111 of the carbon rod 11, allowing the carbon rod 11 to be directly electrically connected to a circuit board or a housing through the elastic member 12, thereby conducting shaft current and eliminating the need for a brush braid, thereby improving the integration of the carbon brush assembly 10 and reducing costs. Furthermore, the carbon rod 11 does not need to be pre-embedded before being pressed and formed, and is not restricted by internal structural components during machining, allowing for the machining of more complex contours and expanding application scenarios.
[0037] In addition, the elastic member 12 can continue to provide thrust to the carbon rod 11 to move in a preset direction to drive the carbon rod 11 to move toward the shaft so that the contact surface of the carbon rod 11 can contact the end face and / or circumferential surface of the shaft. At this time, the shaft current can be transmitted to the carbon rod 11, and then transmitted to the circuit board through the elastic member 12, and then transmitted to the grounded casing through the circuit board, or the shaft current can be directly transmitted to the grounded casing through the elastic member 12 to solve the problem of bearing electrical corrosion.
[0038] It should be noted that the electrical function of the circuit board is to reduce the voltage ratio between the inner and outer rings of the bearing by adding a wire bypass connected to a resistor and a capacitor through the capacitor connected in parallel with the bearing, thereby avoiding EDM (Electrical Discharge Machining) discharge caused by the breakdown of the oil film when the voltage between the inner and outer rings is too high, thereby causing electrical corrosion to the bearing; at the same time, the capacitor is connected in series with the resistor to reduce the high-frequency loop current and avoid the influence of differential mode voltage on the bearing.
[0039] As some examples, the carbon rod 11 has a contact surface for contacting the shaft. When the elastic member 12 drives the carbon rod 11 to move toward the shaft, the contact surface of the carbon rod 11 can contact the circumferential surface of the shaft or the end surface of the shaft to derive the shaft current.
[0040] In actual application, one end of the elastic member 12 can be connected to the carbon rod 11 by means of clamping, screwing, bonding, surface mounting technology, etc. In addition, the other end of the elastic member 12 can also be connected to the circuit board by means of clamping, screwing, bonding, surface mounting technology, etc.
[0041] In actual application, the elastic member 12 can be an elastic structure such as a spring or a spring sheet.
[0042] See also Figure 1 In one embodiment of the present invention, the elastic member 12 is a strip-shaped elastic member 12. Compared with a spring of a coil spring or the like, the strip-shaped elastic member can not only improve the current carrying capacity, but also better guide the axial current from the carbon rod 11 to the circuit board or the housing.
[0043] In practical applications, the strip-shaped elastic member may be formed by a plurality of arc-shaped elastic pieces, or may be formed by a plurality of V-shaped elastic pieces.
[0044] Further, see Figure 1 In one embodiment of the present invention, the elastic band 12 includes a plurality of V-shaped spring pieces 121 connected end to end.
[0045] Such an arrangement allows the elastic member 12 to form a toothed spring structure, which not only has a higher elastic force but also can improve the current carrying capacity and can better guide the shaft current from the carbon rod 11 to the circuit board or the housing.
[0046] In actual application, elastic members 12 with different elastic coefficients may be used to adjust the elastic force of the elastic member 12 on the carbon rod 11 .
[0047] See also Figure 1 In one embodiment of the present invention, one end of the elastic member 12 is detachably connected to the end portion 111 of the carbon rod.
[0048] With this arrangement, the elastic member 12 is connected to the carbon rod 11 in a detachable manner. When the carbon rod 11 is severely worn after being used for a period of time, it is only necessary to remove the carbon rod 11 from the elastic member 12 and replace it with a new carbon rod 11. There is no need to replace the entire carbon brush assembly 10 or even the entire shaft electro-corrosion inhibition assembly, which can reduce costs.
[0049] In actual application, one end of the elastic member 12 can be detachably connected to the end portion 111 of the carbon rod by means of a clamping connection, a screw connection, or the like.
[0050] See also Figure 1 In one embodiment of the present invention, one end of the elastic member 12 is connected to the end portion 111 of the carbon rod through a snap-fit structure.
[0051] In this arrangement, by using a snap-fit structure to connect one end of the elastic member 12 to the end 111 of the carbon rod 11, it is easier to disassemble and assemble the elastic member 12 and the carbon rod 11 without using disassembly tools, which can simplify the assembly process.
[0052] In actual application, the buckle structure can be a structure in which buckles cooperate with each other, or a structure in which buckles cooperate with each other and a slot.
[0053] See also Figure 1 In one embodiment of the present invention, the buckle structure includes a buckle and a slot. One of the elastic member 12 and the end 111 of the carbon rod is provided with a buckle, and the other one is provided with a slot. The buckle and the slot are engaged with each other.
[0054] With such a configuration, the elastic member 12 is connected to the end portion 111 of the carbon rod 11 by the cooperation of the buckle and the slot, which can achieve a better snap connection effect and improve the connection reliability between the elastic member 12 and the carbon rod 11.
[0055] In one embodiment, the buckle is provided at one end of the elastic member 12 , and the slot is provided at the end 111 of the carbon rod 11 .
[0056] In another embodiment, the buckle is provided at the end portion 111 of the carbon rod 11 , and the slot is provided at one end of the elastic member 12 .
[0057] See also Figure 1 In another embodiment of the present invention, one end of the elastic member 12 is welded to the end portion 111 of the carbon rod.
[0058] In this configuration, one end of the elastic member 12 is fixed to the end portion 111 of the carbon rod 11 by welding, which can effectively ensure the connection strength between the elastic member 12 and the carbon rod 11 .
[0059] As some exemplary embodiments, one end of the elastic member 12 may be connected to the end portion 111 of the carbon rod 11 by using a resistance welding process.
[0060] See also Figure 1 In another embodiment of the present invention, the end portion 111 of the carbon rod is provided with a contoured groove 112 , and one end of the elastic member 12 is installed in the contoured groove 112 .
[0061] In this way, by providing the contoured groove 112 at the end 111 of the carbon rod 11 , the elastic members 12 of different sizes and shapes can be assembled.
[0062] It should be noted that, in actual application, the connection method between the elastic member 12 and the carbon rod 11 is not limited to the above-mentioned fixing method, and can be any combination of the above-mentioned fixing methods, or can also be some other fixing methods.
[0063] See also Figure 1 In one embodiment of the present invention, the end of the elastic member 12 away from the carbon rod 11 is used for electrically connecting to the circuit board, or for connecting to the housing.
[0064] With this arrangement, when the elastic member 12 provides thrust to the carbon rod 11 to move in a preset direction, the carbon rod 11 moves toward the shaft to contact the shaft, and the shaft current can be directed to the carbon rod 11. The shaft current is then directed to the elastic member 12 and the circuit board in turn, and finally to the grounded casing through the circuit board, or the shaft current is directly directed to the grounded casing through the elastic member 12, so as to smoothly conduct the shaft current.
[0065] As some examples, when the end of the elastic member 12 away from the carbon rod 11 is used to electrically connect to a circuit board, the circuit board has a capacitor, and the end of the elastic member 12 away from the carbon rod 11 can be electrically connected to the capacitor on the circuit board.
[0066] See also Figure 1 In one embodiment of the present invention, one end of the elastic member 12 away from the carbon rod 11 is mounted on the circuit board using surface mounting technology (SMT).
[0067] Such a setting is equivalent to integrating the connection process by adopting the surface assembly technology mounting method, replacing the carbon rod 11 with the pre-embedded brush braid wire and elastic part 12, and then welding the brush braid wire and elastic part 12 to the hardware through resistance welding, and the hardware and the circuit board are then fixed to the carbon brush nail through screws, thereby improving the integration of the process.
[0068] The present invention also proposes an electric drive system, which includes a casing, a shaft and a shaft corrosion suppression assembly. The specific structure of the shaft corrosion suppression assembly refers to the above-mentioned embodiment. Since this electric drive system adopts all the technical solutions of all the above-mentioned embodiments, it has at least all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be repeated here one by one.
[0069] The shaft is arranged in the casing; the carbon rod is electrically connected to the circuit board or the casing through the elastic member 12. When the elastic member 12 provides a thrust to the carbon rod 11 in a preset direction to drive the carbon rod 11 to move toward the shaft, the contact surface of the carbon rod 11 contacts the circumferential surface and / or end face of the shaft.
[0070] It can be understood that the elastic member 12 can provide a thrust to the carbon rod 11 in a preset direction to drive the carbon rod 11 to move toward the shaft, so that the contact surface of the carbon rod 11 can contact the end face and / or circumferential surface of the shaft. At this time, the shaft current can be transmitted to the carbon rod 11, and then transmitted to the circuit board through the elastic member 12, and then transmitted to the grounded casing through the circuit board, or the shaft current can be directly transmitted to the grounded casing through the elastic member 12 to solve the problem of bearing electrical corrosion.
[0071] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made using the contents of the present invention specification and drawings under the technical concept of the present invention, or direct / indirect application in other related technical fields are included in the patent protection scope of the present invention.
Claims
1. A shaft electrical corrosion suppression assembly, characterized in that: include: circuit boards; A carbon brush assembly, comprising: Carbon rods, an elastic member, one end of which is electrically connected to the end of the carbon rod and keeps the carbon rod moving in a preset direction to provide thrust; The carbon rod is electrically connected to the circuit board through the elastic member, or is used to be connected to the housing.
2. The shaft galvanic corrosion suppression assembly according to claim 1, wherein: The elastic member is a belt-shaped elastic member.
3. The shaft galvanic corrosion suppression assembly according to claim 2, wherein: The strip-shaped elastic member includes a plurality of V-shaped elastic pieces connected end to end.
4. The shaft electrical corrosion suppression assembly according to any one of claims 1 to 3, wherein: One end of the elastic member is detachably connected to the end of the carbon rod.
5. The shaft electrical corrosion suppression assembly according to claim 4, wherein: One end of the elastic member is connected to the end of the carbon rod through a snap-fit structure.
6. The shaft galvanic corrosion suppression assembly according to claim 5, wherein: The buckle structure includes a buckle and a slot. One of one end of the elastic member and the end of the carbon rod is provided with the buckle, and the other end is provided with the slot. The buckle is engaged with the slot.
7. The shaft electrical corrosion suppression assembly according to any one of claims 1 to 3, wherein: One end of the elastic member is welded to the end of the carbon rod; And / or, the end of the carbon rod is provided with a contoured groove, and one end of the elastic member is installed in the contoured groove; And / or, one end of the elastic member away from the carbon rod is used for electrically connecting to a circuit board, or for connecting to a housing.
8. The shaft galvanic corrosion suppression assembly according to claim 1, wherein: One end of the elastic member away from the carbon rod is mounted on the circuit board by using surface mounting technology.
9. An electric drive system, characterized in that: include: chassis; a shaft disposed in the housing; The shaft electrical corrosion suppression assembly according to any one of claims 1 to 8, wherein the carbon rod is electrically connected to the circuit board or the housing via the elastic member, and when the elastic member provides the carbon rod with a thrust force in a preset direction to drive the carbon rod toward the shaft, the contact surface of the carbon rod contacts the circumferential surface and / or end surface of the shaft.