March 06, 2013
Automation GT Service Technician Shares with ControlDesign.com how to Optimize an Assembly Process with Automation
Automation GT Senior Customer Service Technician, Paul Simmons, has been featured by ControlDesign.com. Simmons explains how Automation GT helped define and optimize the assembly process of a customer’s ophthalmology lens product.
As a machine builder that does 80–90% of its business in one-off custom projects, we’re accustomed to working closely with manufacturers to build an automation solution for the products they make. They have a goal and a proven process. They need us to build a machine to automate that process.
For a recent customer, however, the process was less refined from the start, so we got involved at a deeper level.
I worked very closely with the process engineers and chemical engineers to develop the process, and we were able to create a very successful machine implementation to improve automation.
The assembly system was needed for high-end custom eyeglass lenses. The lenses are made of three layers of parts: the base, the lens polymer, and the cap. The manufacturer required an automated system that would begin by placing a layer of adhesive on the outside of the base. Once the adhesive was in place, the cap was to be placed on top, creating an open chamber between the base and the cap. After the adhesive was cured with a UV light, a lens polymer was injected into the open chamber.
The client’s product is based on a desktop machine that optometrists can use to make a topographical map of a patient’s eye, taking away the guesswork that goes along with the typical apparatus used for eye exams. The prescription would be matched up with the chosen frames and a custom set of lenses — with five different lenses glued together — that would go through a baking and curing process, then to a CNC machine to custom-grind the lenses, and a laser marker to create the logo. The final product was a very high-end pair of glasses.
As customers often do, this manufacturer changed its process several times as it developed. So the process still was being ironed out when they came looking for a way to better automate it.
Automation GT designed an assembly machine consisting of an indexing dial with eight stations, accompanied by a ninth station off the indexing dial. Indexing dials are very efficient for systems with multiple subassemblies. With several processes that require time — pad printing, adhesive dispensing, silicon dispensing, oven curing, etc . — it was much more efficient to do them simultaneously than in a linear assembly line, getting 10 things to go on in the same 10 seconds.
But indexing dials also add complexity to the system. Each of the processes, along with pressure checks and vacuum checks, has to send pass/fail information back to the PLC, with each process synched up together. One configuration uses two indexing dials, with 18 stations having 16–17 processes going on at once and two PLCs communicating with each other.
Ultimately, though, the dial machine took the place of six workers. Before approaching Automation GT for a solution, the manufacturer produced one lens per minute. The new machine now produces one lens every 10 seconds in a production environment.
The customer is able to make a product more cost-effectively, enabling the business to grow more quickly. Automation has not only enabled faster production, but also more-repeatable and reproducible production.
From our perspective, this project showed that we could branch out and get more involved earlier on with customers to really help them refine their process and achieve more optimized automation. Very rarely had we been involved at such an R&D level. For example, just figuring out the best way to inject the liquid polymer into the lenses was a science project, and we tried several different solutions to make sure we had the right dispensing system with the right sensors placed optimally in the system.
We have considerable experience with mission-critical applications in life sciences industries that require exceptional precision and reliability. We realize that we can use that knowledge to partner with customers earlier in their development to help them best automate their production.