Emerald Group Publishing Limited
Copyright © 2011, Emerald Group Publishing Limited
Cobra Feeder to increase placement rates by 25 percent
Article Type: New products From: Soldering & Surface Mount Technology, Volume 23, Issue 4
Essemtec, the Swiss manufacturer of production systems for electronics, launched the Cobra Feeder, a new type of SMT component feeder, at the SMT Exhibition held in Nuremberg, Germany in May this year. The double-8-mm feeder can increase the placement rate of Cobra and Paraquda pick-and-place machines by up to 25 percent. Swiss watch technology has inspired the development of the new Cobra Feeder by enabling construction of a feeder that is precise, reliable and compact. The double-8-mm Cobra Feeder only requires 20 mm of space on a feeder rack. The double-8-mm feeder reliably handles paper and blister tapes and it allows tape splicing. The feeder is suitable for all components down to the smallest 01005s (Figure 1).
Drive technology from watches
Indexing 4 mm only take 60 ms in a Cobra Feeder, making it one of the world’s fastest. A high-precision indexing wheel moves the component tape forward. The drive system uses a gear type commonly found in watches. The system is self-locking, highly reliable, simple in construction and easy to maintain.
The position of the wheel, as well as the tape, is measured directly on the indexing finger. Tolerances of the indexing wheel are registered and electronically compensated. This is an important innovation because it makes feeding more precise than other systems that rely on external signals, e.g. from encoders.
Compared to standard mechanical or pneumatic feeding systems, the Cobra Feeder regulates both acceleration and speed. This prevents components from jumping out of the tape.
Pick-up from four feeders simultaneously
A Cobra Feeder is intelligent, meaning that the pick-and-place machine automatically recognizes the feeder and knows what component it holds. The feeder can even be replaced by another during production – the machine notices any changes.
Because of a reference mark on each feeder, position deviations and mechanical tolerances are automatically compensated. This makes feeding and component positioning so exact and reproducible that four components from four different feeders can be picked up simultaneously. The feeders and the pick-up axes have a matching grid. This simultaneous pick-up results in remarkable placement speed.
Feeders are frequently changed; therefore, component set up must be simple and secure. With the Cobra Feeder, tape and cover tape feed-in is motorized, fast and simple. The automatic cover draw-in system allows faster set up than with other feeding systems.
Feeder set up stations are available as an external system or as flexible modules installed on the machine. The Cobra Feeder can be set up with a radio barcode reader. The intelligent feeder transmits the component type, the quantity and the availability to the database system.
Each feeder features an integrated status indicator with LED, so that the operator can observe the status of all feeders at a glance. Each feeder slot is equipped with a feeding button to trigger indexing or to feed-in tape and cover tape on set up.
Active retracting of tape and cover tape
To ensure continuous, jam-free operation, the Cobra Feeder features active retracting of the tape and cover tape. A tooth-wheel belt conveyor ensures that the tape waste is pulled to the back and fed out of the feeder. With this, the feeder can continuously operate without support, even with spliced tapes.
Additionally, as an option, a cutter can be installed inside the feeder. Featuring programmable cutting length, it shreds tape and cover tape into small pieces that can be disposed of easily.
25 percent more throughput
Despite its compact size, accuracy and speed, the construction of the Cobra Feeder is simple. It is optimized for high reliability and simple maintenance. For example, all electronic connections are pluggable. Most maintenance work can be done at the customer site.
The Cobra Feeder first will be available as a double-8-mm version for Cobra and Paraquda pick-and-place machines, and can make those machines up to 25 percent faster due to the faster indexing speed and the possibility of simultaneous pick-up. The double-8-mm feeder is suitable for all chips (from 01005 up to 1206), SOT and other small components supplied in 8 mm tapes. Cobra Feeders for other tapes such as 12 mm will be introduced in the future.