Exchange Forum
High Energy Electronic Coil Potting
Production made more efficient and with higher quality through the use of the EXACT HD – VC24 Vacuum Chambers.
Electronic High Voltage Coil manufacturers in the Marine, Aerospace and Automotive Transportation markets require their products to be fully encapsulated, saturated and void free with their resin of choice. EXACT Dispensing Systems can accomplish this with its new, “High Density – 24 Vacuum Chamber with Enhanced Integrated Control” (EIC).
The Challenge:
A North American manufacturer recently turned to EXACT Dispensing with their special requirements associated with the production of high voltage coils. They had several critical requirements:
- The product must be produced with a void free result – the only way to assure this was to encapsulate the parts under a highly controlled vacuum condition.
- They must have a system that can produce enough parts in each production shift to meet anticipated user demand.
- The meter mix equipment used to supply the required vacuum chamber had to be rugged and trouble free even when working with a filled, abrasive formulation.
- The resin must be heated to a flowable viscosity and temperature controlled throughout the entire dispensing system.
The Solution:
The solution that has now been operational since 2014 is the “EXACT 9450 SA Metering System” utilizing the “Hot Box” heated cabinet feeding the “High Density VC 24″ vacuum chamber. The entire system is controlled with EXACT’s EIC Control console which includes a full color HMI interface.
In this project, EXACT started the system development at the point of dispense where we looked at the vacuum requirements of the part and the production volume requirements of the factory. This thorough review lead EXACT to develop the new High Density VC 24 vacuum chamber. The unique rotary XY dispense tip positioning system inside the VC 24 vacuum chamber maximizes the part count. This creative design allows the chamber to utilize a full 24″ by 24” square pallet of parts for maximum part density within the chamber. The XY automation reaches into the corners of the pallet leading to an increase in part load capacity of approximately 25%.
For this installation EXACT also produced a set of custom “Part Pallets” that provide consistent part placement into the VC chamber with easy load and unload characteristics.
Metered 2-part Epoxy is fed through the center inlet porting of the HD VC24 chamber with disposable fluid lines and static mixer. This approach allows easy and low cost daily operation without purge or difficult daily maintenance procedures.
The Epoxy formulation dispense is controlled by two, synchronized valves in series. The EXACT Model 400 Auto Valve precisely controls the flow of metered epoxy through the static mixer and fluid line. Within the chamber, at the “point of dispense” is a synchronized fluid pinch valve that releases the fluid into the product. This synchronized control valve combination provides crisp, “drip free” material flow from the 9450 SA metering system.
For this application, EXACT configured the 9450 SA metering system for a 5:1 mix ratio by volume. The 9450 series is a very robust metering unit that can supply a whopping 1800cc per stroke (at 1×1). Easily enough resin to fill numerous parts before a recharge is required. This large displacement equates to reduced displacement motion and lends to extended system life. This is especially important with highly filled epoxy resins used in this industry.
The SA “Single Acting” version was selected for the application for its ease of “end of day” shut down. Its ability to evacuate the filled formulation from its metering cylinders, eliminates filler from settling within the large cylinders during idle periods.
To ease the flow of the formulation into the part, EXACT integrated their 9450 SA with the “Hot Box” heated enclosure. This option evenly warms the viscous material to reduce viscosity and allow smooth, uniform flow into the parts within the VC 24 vacuum chamber.
The entire system is controlled by a precision EIC – Enhanced Integrated Control and HMI. All elements of the process including dispense volumes, point of dispense locations, temperature control, vacuum control and the necessary system interface are controlled from EXACT’S powerful EIC.
This user and others like them are enjoying the high performance advantages of the HD VC24 vacuum chamber and the extremely reliable 9450 SA metering system from EXACT.
EXACT Products Supplied:
- 9450 Single Acting
- Hot Box
- HD VC24 Vacuum Chamber
- Enhanced Integrated Control (EIC)
