The heartbeat of high-volume and efficient stamping is the ability to accurately and reliably supply material consistently into the punch press. Selecting the appropriate feeder is not an appendage decision process, but rather critical to efficiency and the quality of parts, as well as reduced waste. What are the common feeders employed and what makes NC servo feeders an emerging favorite in being the essential peripherals in punch press? Let’s look at them.
Common Feeders in Stamping:
1.Air Feeds: They are designed to work with pneumatic power, being inexpensive and simple to use to perform very light duty tasks or in short runs. They force substance in batches. Being relatively inexpensive, they do not usually have exact control of the feed length, and may have problems with consistency, in particular with thicker or wider materials.
2.Mechanical Roll Feeders: They are connected to the punch press through a crank and chains, and hence highly synchronized. They are strong and adaptable to sit in medium-duty usage and have fixed feed lengths that are constant. Nevertheless, the adjustment of feed lengths is to be done mechanically, which slows changeovers and reduces flexibility.
3.Hitch Feeders: These are mostly applied in feeding heavy stock or coil lines wherein the material must be intermittently gripped and yanked. Their acceleration is slower and more basic and have a tendency to be less precise when compared to high speed thin progressive dies work.
The Rise of NC Servo Feeders: Unlocking Precision and Flexibility
NC (Numerically Controlled) servo feeders constitute a huge technological advance by providing unique benefits which directly meet the needs of modern, efficient stamping:
1.Unmatched Precision & Repeatability: The competitive edge. The feed rolls are powered by a high-torque servo motor to great precision using precision devices such as ball screws or high ratio gearboxes. Feed length accuracies are parts-per-fraction-of-a-millimeter achievable using closed-loop feedback that monitors position and makes variations automatically on-the-fly. This plays a very important role in technical progressive dies, close tolerances and reducing wastage of materials.
2.Infinite Feed Length Flexibility: It is easy to change the lengths of feed. Just enter the new value in the control system -no mechanical manipulation, gear changing, no downtime. This allows quick job changes (SMED principles) and the ability to run a large range of different part sizes on the same line of presses with little interruption.
3.Optimized Feeding Modes: NC servo feeders do not only offer intermittent feeding modes, but also advanced mode:
●Step Feeding: Exact feeding subsequent to every press stroke (normal).
●Pitch Accumulation: Pitch feeding during stopping of the press (e.g. at coil change) followed by sufficiently quick manufacturing to close the gap.
●Feed-While-Press-Running: Enables the coordination of feeding motion to take place, in part, during the press cycle (non-dwell feeding) to achieve maximum line speed.
4.Reduced Material Stress & Waste: Better acceleration/deceleration profiles can be achieved since the material must not be jerked around as in mechanical feeders. This more sensitive treatment reduces marking of materials, distortion (generally more important with pre-finished metals) and edge breakage, resulting in superior finished material and a reduction in scrap.
5.Seamless Press Integration: Modern NC servo feeders are true peripherals; i.e. they talk directly to the punch press controller. The tight integration enables simultaneous operations, safety interlocks, automatic feed length setting dependent on the press program, and synchronous start/stop operations to result in an overall line efficiency and safety.
6.Simplified Setup & Operation: Simple touch screens allow easy programming of feeds length, speed and modes. They are simpler to diagnose and it is easy to store the recipes with respect to various productions.
7.Energy Efficiency: Because servo motors are only active during the feeding motion itself, as opposed to having motors which are run continuously in other systems, there is the potential of energy savings.
Conclusion
Although such simpler feeders as air feeds or Mechanical roll feeds also continue to find their niche in less demanding applications, the benefits of NC servo feeders are hard to deny in operations interested in precision, flexibility, optimized efficiency and less wastage. Their capability of providing precise feed lengths on a continuous basis, ability to operate on the new job instantly, serve as an ideal companion to the punch press, and tenderness towards the material, make it an invaluable peripheral to contemporary stamping plants with a competitive edge in mind. When one decides to invest in NC servo feeder, he is investing in quality, throughput, and low cost operation.