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This post was last edited by sdscj0122 on 2020-6-21 at 19:52. The collector ring of 360-degree power supply devices is also known as a conductive ring, slip ring, current collector ring, or gathering ring. It can be used in any electromechanical system that requires continuous rotation while also needing to transmit power and signals from a fixed position to a rotating position. Slip rings can improve system performance, simplify the system structure, and prevent wires from being twisted during rotation. Motors such as slip-ring series synchronous motors and asynchronous motors that utilize slip rings are widely used in industrial sectors, and most of them operate under various harsh conditions. Although these motors lack the commutation function of DC motors, they suffer from the same drawbacks as commutators, such as abnormal wear of slip rings or brushes, brush vibration, and spark generation. Especially in terms of brush material, not only graphite brushes are used for commutator brushes, but metal-graphite brushes are sometimes employed as well to increase the current density of the brushes; therefore, factors such as abnormal residual expansion must also be taken into consideration. Even for high-speed motors such as turbogenerators, or motors operating in fully enclosed gas or hydrogen environments, there are many problems. The material used for slip rings must have high mechanical strength and be an excellent conductor of electricity. It must also be resistant to corrosion, and possess wear resistance as well as stable sliding contact properties when in contact with brushes. Generally, steel slip rings have good wear resistance and high mechanical strength; therefore, they are mostly used in synchronous motors where polarization causes significant wear of the slip rings. Generally, steel slip rings have good wear resistance and high mechanical strength; therefore, they are mostly used in synchronous motors where polarization causes significant wear of the slip rings. Steel can be processed into complex structures; it is a readily available and cost-effective material, which is why it is widely used in synchronous motors, including those with low peripheral speeds. For slip rings in devices such as turbogenerators, where mechanical strength and wear resistance at high circumferential speeds are of primary importance, forged steel is sometimes also used. Additionally, when corrosion resistance is required, stainless steel can be used, but its sliding properties are unstable; when combined with brushes, this often causes the brushes to vibrate, leading to excessive temperature rise or abnormal wear in the brushes. Therefore, special care must be taken when using it. Compared to steel slip rings, copper slip rings such as those made of bronze have better sliding properties, which gives them a wide range of applications. However, when they contain large amounts of lead with a low melting point, heat generation at the points where electricity flows can cause lead to dissolve, leading to wear of the slip rings or abnormal wear of the brushes. In the combination of the slip ring and brushes, when the abrasiveness of the brushes is too high and the material of the slip ring is too soft, stepped wear equivalent to the width of the brushes often occurs on the slip ring. Especially fully enclosed motors with high temperatures and low humidity are more prone to excessive wear of the brushes or slip rings. Heavy scarring forms in this way: at first there are only very small scars, and sparks are generated as the brushes fail to collect electricity properly in those areas. Once a spark is generated, the scar gradually worsens and expands, eventually forming a scar of the same size as the sliding contact surface of the brush. Therefore, even if very small sparks are generated by the brushes for the slip ring, attention must be paid to them.