Conducting ring with tensile resistance compensation and tensile resistance compensation method thereof

Abstract

The conductive ring comprises a conductive ring body, a conductive fiber bundle, a limiting sleeve and a memory alloy spring, the conductive fiber bundle is fixedly sleeved with the limiting sleeve, one end of the memory alloy spring is fixedly connected to the limiting sleeve, and the other end of the memory alloy spring is fixedly connected to the limiting sleeve. The other end of the memory alloy spring abuts against and makes contact with the inner wall of the radial hole deformed through extrusion of the press. According to the radial tension resisting method of the conducting ring with the tension resisting compensation function, radial tension is generated on the conducting fiber bundle through the rotating motor shaft, so that the memory alloy spring is compressed, austenite phase change is triggered, and therefore the memory alloy spring generates thrust resisting the radial tension on the conducting fiber bundle; the purpose of preventing the conductive fiber bundle from loosening from the conductive ring body is achieved, the installation reliability of the conductive fiber bundle is improved, and the service life of the whole conductive ring is prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of conductive rings, and in particular to a conductive ring with tensile force compensation. Background Art

[0002] Bearings have been widely used in the automotive industry, machinery manufacturing, aerospace, marine engineering, military and other fields due to their excellent properties in reducing friction, supporting and positioning, bearing loads, reducing energy consumption and extending equipment life. However, in the motor industry, especially in high-voltage motor applications above 400V, there are several situations where electrical corrosion of bearings may occur:

[0003] 1. Leakage: In mechanical equipment, especially motor-driven equipment, if the motor is poorly grounded or the insulation system is aged, leakage current may pass through the bearing. When the leakage current passes through the bearing, an arc will be formed, causing partial discharge and electrical corrosion.

[0004] 2. Static electricity accumulation: In high-speed equipment or equipment with plastic parts, static electricity is easy to accumulate. If the static electricity is not released in time, the current may pass through the bearing, forming a discharge and causing electrical corrosion.

[0005] 3. Improper current loop: In some industrial equipment or generators, the bearings sometimes accidentally become part of the current loop, and the current flows from the shaft through the bearings to the ground. In this case, the bearings will gradually show electrical corrosion under long-term operation.

[0006] 4. Variable frequency drive motor (VFD): Motors using variable frequency drives are particularly prone to bearing electrocorrosion. The inverter generates high-frequency voltage, which forms a current through the motor shaft and bearings, causing electrocorrosion problems to be particularly common in variable frequency motors.

[0007] Electrical corrosion can cause many hazards, such as bearing surface damage, lubricant degradation, increased noise and vibration, shortened bearing life, etc. This seriously hinders its application. Especially for high-voltage motors with voltages exceeding 800V, higher platform voltages raise the shaft voltage, higher switching frequencies mean more breakdown times, higher motor power causes a surge in inductive energy, and more severe working conditions make the bearing oil film more prone to breakdown, and special attention must be paid to the risk of electrical corrosion on the reduction gearbox side bearing. The motor conductive ring is a device that uses a conductive medium to direct the motor shaft current to the motor housing to prevent the shaft current from passing through the bearing and producing electrical corrosion of the bearing. In theory, if the resistance of the conductive ring is small enough, the bearing can effectively avoid the defect of electrical corrosion.

[0008] At present, the structures of conductive rings mainly include: carbon brush type, multi-layer stacking type, multi-hole press-fit type and so on.

[0009] The structural principle of the carbon brush type is: a carbon rod is installed radially on the conductive ring, and a spring is installed in the radial direction of the carbon rod. The spring pushes the carbon rod toward the center of the conductive ring. Under the thrust of the spring, the carbon rod is always pressed on the rotating motor shaft, and the motor shaft current is transmitted from the high-speed rotating shaft to the shell. Then it is connected to the earth, and the voltage of the motor shaft and shell is 0 or the voltage difference is 0, thereby avoiding electrical corrosion of the production bearing.

[0010] The principle of the multi-layer stacking structure is: using injection molding or machining technology, the upper layer, middle layer and lower layer of the conductive ring are made separately. The conductor (for example, conductive fiber) is installed on the middle layer, and then the three layers are fixed together by bolts or molding glue, etc., forming a conductive ring in which the conductor (for example, conductive fiber) can contact the high-speed rotating motor shaft and the conductive ring body can be installed on the motor housing. The function of guiding the motor shaft current to the housing is realized, eliminating electrical corrosion of the bearing.

[0011] The structural principle of the multi-hole press-fit type is: use machining to process a single conductive ring body, first process the through-hole installation hole of the conductor (for example, conductive fiber) in the radial direction, and then process the press-fitting forming hole of the conductor (for example, conductive fiber) in the axial direction on the end face of the conductive ring, which corresponds to the through-hole installation hole of the radial conductor (for example, conductive fiber). Use a press machine to fix the conductor (for example, conductive fiber) in each press-fitting forming hole, thereby forming the structure of the conductive ring. It guides the motor shaft current to flow to the housing or the ground, thereby eliminating the electrical corrosion of the motor bearing.

[0012] At present, the conductive rings made by carbon brushes have large structural dimensions, and the carbon brushes are subject to physical wear, which easily forms a large amount of carbon powder, wears quickly, and shortens the life of the conductive rings. The multi-layer stacked conductive rings have too many parts, resulting in low production efficiency and high production costs. There is also the risk of fasteners falling off and causing other safety hazards. The multi-hole press-fit conductive rings have many processing surfaces and require machine tools with more than three axes, resulting in high production equipment costs. The number of press-fit forming holes is large, and they need to be processed one by one, resulting in low production efficiency. In addition, the radial tension on the conductive fiber bundle when the motor shaft rotates at high speed can cause the conductive fiber bundle to loosen.

[0013] It can be seen that the existing technology still needs to be improved and enhanced. Summary of the invention

[0014] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a conductive ring with anti-tensile force compensation and an anti-tensile force compensation method thereof, aiming to solve the technical problem in the prior art that the radial tension generated by the high-speed rotation of the motor shaft causes the conductive fiber bundle to easily loosen from the conductive ring body.

[0015] In order to achieve the above object, the present invention adopts the following technical solutions:

[0016] A conductive ring with tensile force compensation, which includes a conductive ring body and a plurality of conductive fiber bundles, a limiting sleeve is sleeved on the outer side of the conductive fiber bundle, one end of the limiting sleeve is connected to a memory alloy spring, the conductive ring body is annularly provided with a plurality of radial holes for installing the conductive fiber bundle, the plurality of radial holes are annularly arranged around the axis of the conductive ring body, the axes of the plurality of radial holes are located on the same plane, one side of the conductive ring body is concavely provided with a front extrusion groove, and the other side of the conductive ring body is concavely provided with a back extrusion groove, the front extrusion groove and the back extrusion groove are used for being extruded and deformed by an external press so that the inner wall of the radial hole presses the conductive fiber bundle, and one end of the memory alloy spring away from the limiting sleeve stops contacting the deformed inner wall of the radial hole.

[0017] Specifically, the front extrusion groove and the back extrusion groove are both annular grooves coaxial with the conductive ring body, the outer diameter of the front extrusion groove is smaller than the inner diameter of the back extrusion groove, and the end of the memory alloy spring contacts the inner wall of the radial hole that is extruded and deformed at the front extrusion groove.

[0018] Specifically, the conductive ring body is provided with at least two axial holes, the at least two axial holes penetrate through two axial surfaces of the conductive ring body, and the at least two axial holes are staggered with the plurality of radial holes.

[0019] Specifically, a chamfered right-angle structure is provided at one end of the radial hole close to the outer side of the conductive ring body.

[0020] Specifically, a rounded corner structure is provided at one end of the radial hole close to the inner side of the conductive ring body.

[0021] A method for compensating the tensile force of a conductive ring with tensile force compensation, wherein the conductive ring with tensile force compensation as described above is used, comprises the following steps:

[0022] S01, the inner end of the conductive fiber bundle contacts the motor shaft, and the motor shaft rotates at a high speed to generate a radial pulling force on the conductive fiber bundle close to the motor shaft;

[0023] S02. When the motor shaft reaches a certain speed, the radial tension generated causes the conductive fiber bundle to move closer to the motor shaft, the memory alloy spring is compressed, triggering the austenite phase transformation, and the elastic force of the memory alloy spring pushes the conductive fiber bundle to move away from the motor shaft to counteract the radial tension.

[0024] Beneficial effects:

[0025] The present invention provides a conductive ring with anti-tension force, comprising a conductive ring body, a conductive fiber bundle, a limiting sleeve and a memory alloy spring, wherein the limiting sleeve is fixedly sleeved on the conductive fiber bundle, one end of the memory alloy spring is fixedly connected to the limiting sleeve, and the other end of the memory alloy spring is in contact with the inner wall of the radial hole deformed by the press. The anti-radial tension method of the conductive ring with anti-tension force generates radial tension on the conductive fiber bundle through the rotating motor shaft, so that the memory alloy spring is compressed, triggering the austenite phase change, so that the memory alloy spring generates a thrust to the conductive fiber bundle to resist the radial tension, thereby achieving the purpose of preventing the conductive fiber bundle from loosening from the conductive ring body, improving the installation reliability of the conductive fiber bundle, and extending the service life of the conductive ring as a whole. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of the three-dimensional structure of a conductive ring with radial tension compensation provided by the present invention;

[0027] Figure 2 A schematic diagram of the cross-section structure of a conductive ring with radial tension compensation provided by the present invention;

[0028] Figure 3 The present invention provides Figure 2 Schematic diagram of the local structure of A;

[0029] Figure 4 The present invention provides Figure 3 Schematic diagram of the local structure of B;

[0030] Figure 5 This is a flowchart of the tensile force compensation method provided by the present invention.

[0031] Reference numerals:

[0032] 1—conductive ring body 2—conductive fiber bundle 3—limiting sleeve

[0033] 4—Memory alloy spring 11—Radial hole 12—Front extrusion groove

[0034] 13—reverse extrusion groove 14—axial hole 15—rounded corner structure. DETAILED DESCRIPTION

[0035] The present invention provides a conductive ring with tensile force compensation and a tensile force compensation method thereof. In order to make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0036] In the description of the present invention, it should be understood that the terms "upper", "lower", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, and a specific direction structure and operation, and therefore, cannot be understood as a limitation on the present invention. In addition, "first" and "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0037] See also Figures 1 to 4 As shown, the present invention provides a conductive ring with tensile force compensation, which includes a conductive ring body 1 and a plurality of conductive fiber bundles 2. A limiting sleeve 3 is sleeved on the outer side of the conductive fiber bundle 2, and one end of the limiting sleeve 3 is connected to a memory alloy spring 4. The conductive ring body 1 is annularly provided with a plurality of radial holes 11 for installing the conductive fiber bundle 2. The plurality of radial holes 11 are arranged in a ring around the axis of the conductive ring body 1, and the axes of the plurality of radial holes 11 are located on the same plane. A front extrusion groove 12 is concavely provided on one side of the conductive ring body 1, and a reverse extrusion groove 13 is concavely provided on the other side of the conductive ring body 1. The front extrusion groove 12 and the reverse extrusion groove 13 are used for being extruded and deformed by an external press so that the inner wall of the radial hole 11 presses the conductive fiber bundle 2, and one end of the memory alloy spring 4 away from the limiting sleeve 3 stops contacting the deformed inner wall of the radial hole 11. In this embodiment, the diameters of the front extrusion groove 12 and the back extrusion groove 13 are different, so that the two are staggered in cross section. The limiting sleeve 3 and the memory alloy spring 4 are located between the front extrusion groove 12 and the back extrusion groove 13. The conductive fiber bundle 2 is formed by 12,000 conductive fibers with a single diameter less than 1 micron gathered together. The end of the conductive fiber bundle 2 close to the axis of the conductive ring body 1 protrudes out of the radial hole 11 to form a conductive brush; the trigger pressure of the memory alloy spring 4 can be calculated and designed according to the rotation speed of the motor shaft in actual application. Setting the axes of several radial holes 11 on the same plane is conducive to the opening of grooves on both sides of the conductive ring body 1, so that the distances between the front extrusion groove 12 and the back extrusion groove 13 and the radial hole 11 can be kept consistent, which is convenient for processing and production and extrusion installation of the conductive fiber bundle 2.

[0038] During production, the conductive ring body 1, the conductive fiber bundle 2, the limiting sleeve 3, the memory alloy spring 4 and other individual parts are simply machined, and then the limiting sleeve 3 and the memory alloy spring are fixedly sleeved on the conductive fiber bundle 2, and the conductive fiber bundle 2 is installed in the radial hole 11. The front extrusion groove 12 and the back extrusion groove 13 of the conductive ring body 1 are extruded by a press, so that the hole wall position corresponding to the radial hole 11 is deformed, thereby pressing the conductive fiber bundle 2, so that the conductive fiber bundle 2 is reliably installed and can resist a large radial tensile force. One end of the memory alloy spring 4 is against the deformed inner wall of the radial hole 11, and at the same time, the contact area between the conductive fiber bundle 2 and the conductive ring body 1 is increased, so that the conduction resistance between the two is smaller; the design of the front extrusion groove 12 and the back extrusion groove 13 respectively forms concave surfaces on the inner and outer sides of the two sides of the conductive ring body 1, effectively partially releasing the stress generated in the extrusion molding process of fixing the conductive fiber bundle 2, and avoiding changes in the inner and outer diameter dimensions and tolerances of the conductive ring body 1. When the rotating motor shaft generates radial tension on the conductive fiber bundle 2, the memory alloy spring 4 is compressed, triggering an austenite phase transformation, so that the memory alloy spring 4 generates a thrust on the conductive fiber bundle 2 to counteract the radial tension, thereby preventing the conductive fiber bundle 2 from loosening from the conductive ring body 1, thereby improving the installation reliability of the conductive fiber bundle 2 and extending the overall service life of the conductive ring.

[0039] See also Figure 1 to Figure 2 As shown, the front extrusion groove 12 and the back extrusion groove 13 are both annular grooves coaxial with the conductive ring body 1. The outer diameter of the front extrusion groove 12 is smaller than the inner diameter of the back extrusion groove 13. From the cross section, the front extrusion groove 12 and the back extrusion groove 13 are staggered, forming concave surfaces on the inner and outer sides of the two sides of the conductive ring body 1, respectively, effectively partially releasing the stress generated in the extrusion molding process of the fixed conductive fiber bundle 2, and avoiding changing the inner and outer diameter sizes and tolerances of the conductive ring body 1. The end of the memory alloy spring 4 stops contacting the inner wall of the radial hole 11 that is squeezed and deformed at the front extrusion groove 12. When the radial tension generated by the rotating motor shaft on the conductive fiber bundle 2 is large, the conductive fiber bundle 2 is pulled close to the motor shaft, and the memory alloy spring 4 is compressed, triggering the austenite phase transformation. The memory alloy spring 4 generates elastic force to push the limit sleeve 3 and the conductive fiber bundle 2 away from the motor shaft, thereby preventing the conductive fiber bundle 2 from being pulled loose by the radial tension, or even winding around the motor shaft, affecting the normal operation of the motor shaft.

[0040] See also Figure 1As shown, the conductive ring body 1 is provided with at least two axial holes 14, and at least two axial holes 14 penetrate the two sides of the conductive ring body 1 in the axial direction, and at least two axial holes 14 are staggered with a plurality of radial holes 11. When installing the conductive ring, the conductive ring body 1 can be fixed to the housing of the motor by screws inserted into the axial holes 14. The axial holes 14 are staggered with the radial holes 11 to avoid interference between the conductive fiber bundle 2 in the radial holes 11 and the mounting screws, which affects the installation and use.

[0041] See also Figures 2 to 3 As shown, one end of the radial hole 11 close to the outer side of the conductive ring body 1 is provided with a chamfered right angle structure to facilitate the conductive fiber bundle 2 to enter the radial hole 11 .

[0042] See also Figures 2 to 3 As shown, a rounded corner structure 15 is provided at one end of the radial hole 11 close to the inner side of the conductive ring body 1, which can effectively prevent the conductive ring body 1 from cutting the conductive fiber bundle 2 due to radial tension on the conductive fiber bundle 2 when the motor shaft rotates at high speed.

[0043] See also Figure 5 As shown, a method for compensating the tensile force of a conductive ring with tensile force compensation is provided, wherein the conductive ring with tensile force compensation as described above is used, and the method comprises the following steps:

[0044] S01, the inner end of the conductive fiber bundle 2 contacts the motor shaft, and the motor shaft rotates at a high speed to generate a radial pulling force on the conductive fiber bundle 2 close to the motor shaft;

[0045] S02. When the motor shaft reaches a certain speed, the radial tension generated causes the conductive fiber bundle 2 to move closer to the motor shaft, the memory alloy spring 4 is compressed, triggering the austenite phase transformation, and the elastic force of the memory alloy spring 4 pushes the conductive fiber bundle 2 to move away from the motor shaft to counteract the radial tension.

[0046] It is understandable that those skilled in the art can make equivalent substitutions or changes based on the technical solution and inventive concept of the present invention, and all these changes or substitutions should fall within the protection scope of the claims attached to the present invention.

Claims

1. A conductive ring with tensile force compensation, characterized in that: The invention comprises a conductive ring body (1) and a plurality of conductive fiber bundles (2); a limiting sleeve (3) is sleeved on the outer side of the conductive fiber bundle (2); one end of the limiting sleeve (3) is connected to a memory alloy spring (4); the conductive ring body (1) is provided with a plurality of radial holes (11) for installing the conductive fiber bundle (2) in an annular shape; the plurality of radial holes (11) are arranged in an annular shape around the axis of the conductive ring body (1); the axes of the plurality of radial holes (11) are located on the same plane; a front extrusion groove (12) is concavely provided on one side of the conductive ring body (1); a back extrusion groove (13) is concavely provided on the other side of the conductive ring body (1); the front extrusion groove (12) and the back extrusion groove (13) are used for being extruded and deformed by an external press so that the inner wall of the radial hole (11) is pressed against the conductive fiber bundle (2); and one end of the memory alloy spring (4) away from the limiting sleeve (3) stops contacting the deformed inner wall of the radial hole (11).

2. The conductive ring with tensile force compensation according to claim 1, characterized in that: The front extrusion groove (12) and the back extrusion groove (13) are both annular grooves coaxial with the conductive ring body (1); the outer diameter of the front extrusion groove (12) is smaller than the inner diameter of the back extrusion groove (13); and the end of the memory alloy spring (4) contacts the inner wall of the radial hole (11) that is extruded and deformed at the front extrusion groove (12).

3. The conductive ring with tensile force compensation according to claim 1, characterized in that The conductive ring body (1) is provided with at least two axial holes (14), the at least two axial holes (14) penetrate through two axial surfaces of the conductive ring body (1), and the at least two axial holes (14) are staggered with the plurality of radial holes (11).

4. The conductive ring with tensile force compensation according to claim 2, characterized in that: One end of the radial hole (11) close to the outer side of the conductive ring body (1) is provided with a chamfered right-angle structure.

5. The conductive ring with tensile force compensation according to claim 2, characterized in that: A rounded corner structure (15) is provided at one end of the radial hole (11) close to the inner side of the conductive ring body (1).

6. A method for compensating the tensile force of a conductive ring with tensile force compensation, characterized in that: The conductive ring with tensile force compensation as claimed in any one of claims 1 to 5 is used, comprising the following steps: S01, the inner end of the conductive fiber bundle (2) contacts the motor shaft, and the motor shaft rotates at a high speed to generate a radial pulling force on the conductive fiber bundle (2) close to the motor shaft; S02. When the motor shaft reaches a certain rotation speed, the radial tension generated causes the conductive fiber bundle (2) to move closer to the motor shaft, the memory alloy spring (4) is compressed, triggering an austenite phase transformation, and the elastic force of the memory alloy spring (4) pushes the conductive fiber bundle (2) to move away from the motor shaft to counteract the radial tension.

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