In spooling or level-wind applications, material is wound onto a spool. As the material's diameter changes on the supply spool, and on the the take-up spool, it’s critical to maintain the proper speed of each spool. Encoders provide the motion feedback to help maintain that speed.
Encoder feedback also helps monitor the length of material and helps maintain the proper tension on the material to avoid stretching, breaking or winding too tightly or loosely.
Shaft, thru-bore or measuring wheel encoders can be used in these applications, depending on the system. The encoders may be applied to drive motors, the reel shaft, pinch rollers, or tension rollers. EPC's Model TR1 Tru-Trac®, an integrated encoder measuring-wheel pivot-arm assembly in one unit, is used throughout various industries for spooling or level-wind applications.
Variables such as resolution, output type, channels, voltage, etc., can be specified to meet the individual application requirements. In the vast majority of installations, incremental encoders are most suitable. With uni-directional travel, a single-channel encoder is adequate; however, we recommend quadrature output to avoid edge jitter during stoppage.
Environmental considerations are important when specifying your encoder. Take into account the encoder's exposure to liquids, fine particulates, extreme temperatures, and washdown requirements. An IP66 or IP67 seal protects against moisture ingress, while a stainless steel or polymer composite housing to mitigate the effects of harsh cleaning chemicals and solvents. See Technical Bulletin 106: Sealing Options for EPC Encoders.
Examples of Motion Feedback in Spooling
- Electrical cable reeling or marking
- Flexible packaging roll stock converting
- Flat steel coiling
