Emerald Group Publishing Limited
Copyright © 2011, Emerald Group Publishing Limited
Highly flexible and fast SMD assembly machine
Article Type: New products From: Assembly Automation, Volume 31, Issue 3
The SMD pick-and-place machine, Cobra. Innovative technology and new materials make Cobra one of today’s most modern and accurate machines worldwide. With this machine, Essemtec is targeting a new customer segment.
For the second time in less than a year, Essemtec presents a new SMD placement machine. Paraquda premiered at the Productronica exhibition in late 2009, and now the Cobra (Figure 3) will be shown for the first time at SMT Nuremberg. The surprise: Cobra is not an upgrade but a completely new machine, more powerful and more modern than anything previously seen.
Cobra has been equipped with the best that today’s drive and material technologies have to offer: the XY gantry is driven by linear motors, a high-speed bus system is responsible for the signal processing and the machine’s base is fabricated from a mineral compound with optimal damping characteristics. Furthermore, design engineers focused on properties such as durability, reliability, redundancy and reduced maintenance.
The system’s redundancy is particularly evident when looking at the assembly head: each of the eight assembly axes are equipped with an individual drive system for both, vertical motion and rotation. Therefore, each of the axes can be used for all component types, whether QFP, BGA or chip.
All moving parts of the Cobra are weight optimized to achieve high acceleration yet minimum impact on the precision bearings. For example, the X-beam is made from a carbon-fibre composite material. This fast-moving part is very lightweight but robust. Furthermore, it prevents temperature-related variations because it does not change its shape or size due to temperature changes. These and many other details show that Essemtec is targeting an expanded customer segment with the Cobra.
Five tasks, one machine
Cobra is a pick-and-place system for medium to high volumes, but it also has the flexibility that is required in highly versatile production. Like other Essemtec products, the Cobra can be set up without downtime: feeders are detected automatically and can be exchanged while the machine is running. A unique feature of the Cobra in feeder positioning is that although it is an in line machine, feeders can be mounted from all four sides, even in between the conveyor belts, a space that was always lost space on other machines. Therefore, Cobra’s feeder capacity is very high: up to 240 components can be set up simultaneously.
The component range is remarkable: it spans from 01005 chips to large 100×100 mm modules or connectors with 18 mm height and more. However, Cobra is more than just a pick-and-place system. It can take over tasks that otherwise would require five specialized machines. Chip and fine-pitch placement are standard tasks, and Cobra can be used as a die bonder, a special component placer and a dispenser.
Cobra offers an accuracy of 10 μm (One Sigma) and a speed of 15,000 cph measured according to the IPC-9850 standard. The board size can be up to 600×600 mm, making the Cobra a powerful all-rounder suitable for high-tech as well as low-tech, for prototypes as well as large series. This wide application range makes the Cobra ideal for contract manufacturers who must be able to respond flexibly on all their customer’s requirements, and for a manufacturer who needs to produce large amounts of different PCBs.
Cobra relieves operator
ePlace was shown for the first time on the Paraquda pick and place in late 2009, now it is the operating system of the Cobra as well. With its intuitive, easy-to-use graphical interface, pick-and-place operation is simplified. ePlace also improves machine productivity and product quality.
The software checks all operator entries for validity and logic. If necessary, it proposes better values or online help. If, for example, current feeder positions are not optimal for a maximum productivity, ePlace delivers a proposal for improvement. Or, if the next job requires components not installed yet, ePlace announces this in time. This is how ePlace ensures maximum usage of the resources.
The ePlace operating system is based on “eez-technology,” which was developed by Essemtec. Eez-technology optimizes applications for use on touch-screen input systems. It offers automatic entry completion, a context-sensitive help system, online education and computer-based training, as well as a clearly structured layout. With eez-technology, operators can learn more quickly how to run a machine.
Performance optimized to the last detail
Cobra does more than other machines with eight placement axes because many details are just resolved better. As an example, because of linear motors, optimized damping and real-time signal processing, Cobra can optimize the travel path of all eight axes in three dimensions. Therefore, it can always use maximum acceleration and deceleration values when moving.
Additionally, four of the eight placement axes are arranged in a square, allowing Cobra to pick up up to four components from the feeders at the same time. This is advantageous when mounting chips.
Finally, the new vision has a specialized three-level lighting system. It is optimized in a way that different component types can offer a good contrast even with different types on every nozzle. One single picture will be enough for image processing for the Cobra, while other machines need three or four flashes with different settings in such a situation. These details combine to result in a remarkable performance increase.
For upgrades and first-time users
The new Cobra offers a higher placement rate, a higher feeder capacity, higher accuracy and greater placement area than other pick-and-place machines. However, feeders from CSM, FLX and Paraquda series placement machines are compatible with the Cobra, making it easier to switch or upgrade.
The assembly machine is manufactured in Switzerland and tested with the strictest quality standards. It suits the highest quality and reliability requirements and is one of the most accurate and most modern machines in the world. It is capable of handling future challenges in the electronics industry and, therefore, a safe investment.
Essemtec is a systems provider with global service and support network. The Swiss manufacturer delivers complete turnkey solutions: printers, pick and places, dispensers, reflow systems, handling, transport devices and software for production planning, optimization and tracking, all from one source.