In the precision stamping of motor stator and rotor laminations, large quantities of silicon steel sheets must be manufactured from narrow-width silicon steel strips. These strips are typically stored in coil form. During the stamping process, the silicon steel coil must be continuously uncoiled to feed the progressive stamping press, enabling the high-speed production of lamination sheets.
On traditional silicon steel stamping lines, non-motorized heavy-duty decoilers or non-motorized double-head decoilers are often used for coil handling. In such configurations, the silicon steel coil rests on the cradle arms of the decoiler, while the feeding machine attached to the stamping press pulls the material step-by-step. This pulling force also drives the rotation of the coil. While this setup appears mechanically simple, it creates several performance challenges: the feeding machine bears the entire coil tension, which becomes increasingly unstable as the coil diameter and weight change throughout the production cycle.
To address this issue, many advanced production lines have upgraded to motorized decoilers, where a drive motor actively rotates the cradle arms holding the coil. This reduces the load on the feeder and improves line efficiency. However, even motorized decoilers face limitations: the motor runs at a constant speed, while the coil diameter gradually decreases, leading to variations in uncoiling speed. When the coil is small, this mismatch may even cause the feeder to pull against the decoiler’s rotation, disrupting feeding accuracy and increasing mechanical wear.
To eliminate these problems at the source, our engineering team developed a servo motorized decoiler specifically for stator and rotor stamping lines. This system integrates a servo motor and ultrasonic distance sensing system to deliver synchronized, adaptive uncoiling control.
During operation, the silicon steel coil is mounted onto the decoiler’s cradle arms, which are driven by a servo motor. An ultrasonic sensor measures the distance between the sensor and the outer coil surface in real time, effectively calculating the coil diameter. This data is fed into the servo motor controller, which adjusts the motor’s rotational speed dynamically based on the changing coil size. As a result, the silicon steel strip is always uncoiled at a stable and consistent speed, perfectly matched to the press line’s feeding demands.
This servo-controlled decoiler greatly enhances uncoiling smoothness and feeding precision. It improves the overall dimensional accuracy of the stamped stator and rotor lamination sheets and significantly reduces the mechanical wear on both the decoiler and the feeder.
