Whether it’s a handheld pneumatic benchtop dispenser or a needle valve mounted to a Cartesian robot, there are many technologies for getting an adhesive, sealant or lubricant from a bulk supply and onto a part. By automating the dispensing process, assemblers can minimize waste, ensure quality and increase productivity.
More than 20 suppliers of equipment for dispensing and curing adhesives exhibited at The ASSEMBLY Show last fall. Here is a small sample of the new technologies to be found on the show floor.
Benchtop Dispensing Robot
Techcon Systems has introduced the TSR2000 series of benchtop dispensing robots. These robots can be used to dispense dots of solder paste, form-in-place gaskets, filling, potting, encapsulation, bonding, coating and other applications.
Designed and configured specifically for fluid dispensing applications, the robots provide total control over fluid placement from beads, arcs and circles to repeated timed dots. Programming is done via teach pendant.
Three models are available. Model TSR2201 has a work area measuring 200 by 200 millimeters. Model TSR2301 has a work area measuring 300 by 300 millimeters. Model TSR2401 has a work area measuring 400 by 400 millimeters.
LED-Based Curing Systems
Excelitas Technologies Corp. has launched the OmniCure AC8 series of LED-based UV curing systems. These compact, air-cooled systems provide superior optical uniformity, enhanced process control, and easier integration into assembly lines.
The scalability of the AC8 series allows engineers to adjoin multiple LED heads to achieve larger curing areas.
Models AC8150, AC8150P, AC8225, AC8225P and AC8300 have advanced, custom front-end optics to provide high-powered, high-peak irradiance at different working distances. The systems deliver a peak irradiance of more than 8 watts per square centimeter for fast, even curing at long working distances. Models AC8150P and AC8225P have enhanced optics to optimize the dose for the short working distances required by print applications.
A patented process for addressing individual LED module outputs ensures uniform irradiation over the entire curing area. Precise control of the irradiance level ensures the correct amount of UV light is provided on every exposure for consistent and reliable results.
Benchtop Dual-Cartridge Dispenser
New from Fisnar Inc. is the Model DCD, a bench-mounted dispensing machine for low-volume mixing and dispensing of two-part materials packaged in dual cartridges.
This portable system is simple to install and program for accurate two-part dispensing. The pneumatically controlled dispenser is mounted on a bench support that permits adjustments to the height and angle of dispensing. A compact controller provides all the necessary air logic functions, and maintains control of air pressure to the dispenser.
The machine includes a pneumatically actuated dual-cartridge piston dispenser, which applies pressure to accurately meter the materials. The machine’s static mixer finally combines the two materials, while the piston retraction control facilitates loading and unloading of the cartridge.
The system is equipped with a pinch-valve for increased accuracy and drip-free dispensing of low-viscosity materials. The valve is fitted to the exit tip of the static mixer and operated by an air portal on the controller. A pneumatic foot pedal permits hands-free operation.
Meter, Mix and Dispensing System
Fluid Research will be showing its T-1000 meter, mix and dispense system.
This flexible, benchtop system features a positive-displacement pump and is ideal for medium- to high-volume dispensing nearly all epoxy, silicone and urethane two-part materials.
The microprocessor-controlled device has a touchpad user interface and can store 15 dispense programs. It can accommodate mix ratios from 1-to-1 to 20-to-1 and viscosities ranging from 1 to 50,000 centipoise.
Flow rate can be set from 0.026 to 98 cc per second, and shot size can be set from 0.25 to 500 cc. The dispenser is accurate to ±1 percent or less of the programmed shot size.
Available options include 5-gallon stainless tanks, auto fill, material recirculation, heating, material agitation and a desiccant dryer.
High-Intensity Spot Curing
The MKIII from the Lesco division of American Ultraviolet delivers an intense, concentrated and regulated spot of UV and visible light energy through a light guide. This 100-watt light source can be used for curing adhesives, coatings, inks and other materials.
It outputs light in the visible, UV-A, UV-B and UV-C spectra and is preset at the factory centered at a wavelength of 365 nanometers (UV-A). It produces a peak irradiance of 20,000 milliwatts per square centimeter at a wavelength of 315 to 400 nanometers. The light is generated by a 100-watt DC mercury vapor short-arc lamp.
Robot Dispenses Two-Part Materials
The TR300 from MTA Automation Inc. is a PC-controlled tabletop robot for semiautomatic volumetric dispensing of two-part materials.
The three or four axes of the robot are fully programmable through MTA MotionEditor software, including parameters such as dispense volume, dispensing speed and mixing ratio. The robot can dispense dots, lines or circular beads.
The unique mixing chamber is based on a dynamic mixing chamber. This unit made of stainless steel and plastic and can either be cleaned or changed after use depending on the material. In terms of maintenance, it is advantageous to mix the material just before dispensing. The dispensing nozzles are directly connected to the mixing chamber, ensuring a homogeneous mix and reliable process.
LED Light Source for Adhesive Curing
Hamamatsu Corp. has introduced the Lightningcure LC-L1V3, a compact LED-based light source for UV curing adhesives. The unit can drive up to four LED heads, but is small enough to fit in the palm of one’s hand, which makes it easy to set up in any practically any limited space.
In terms of its light output, the unit produces high-intensity UV beams with roughly half the power consumption of similar products, which contributes to reduced operating cost. It also provides stable light output, thanks to a unique feedback function that minimizes drift during initial light emission and maintains light output during operation.
Engineers can program the strength and duration of UV illumination in just three steps. By storing these programs in the unit, optimal conditions can be achieved so as to improve yield of assemblies that must be precisely bonded. In addition, the device has a key locking function that reduces the risk of mistakenly changing entered programs.
Dispense With a Six-Axis Robot
Nordson Sealant Equipment is now integrating its Servo-Flo 404-IDS dispensing system with MH or ES six-axis robots from Yaskawa Motoman.
The Servo-Flo meter’s servo drive, a Yaskawa encoder and supply pump system controls are all integrated into the Motoman control panel for a smaller footprint, lower system cost and one-stop operator control of the entire robotic dispensing system. The integrated system precisely dispenses fluids with excellent response time for starting and stopping extruded beads.
The Servo-Flo is a positive-displacement, servo-driven meter with a manifold or remote-mounted dispense valve. It can be used for a variety of robotic dispensing applications, such as adhesive bonding, casting, filling, gasketing, molding and sealing. The positive rod displacement meter easily dispenses adhesives and sealants such as one-part epoxies, mastics, silicones, urethanes and abrasive materials.
The meter includes a quick-change dispense valve available in Tip-Seal, No-Drip and Snuf-Bak models for accurate starting and stopping of material flow for beads, shots or dots in streaming, extruding, spraying and high-speed stitching applications. The meter can be mounted on the robot’s wrist or arm, or it can be mounted on a separate pedestal so the robot can present parts to the dispenser.
The complete robotic dispensing system includes supply pumps, hoses and accessories, such as material temperature control, automated waste collection, machine vision, and system integration.
Machine Applies Conformal Coatings
PVA is showing the new Delta 6 conformal coating and dispensing system.
Although the Delta 6 is 4 inches less deep and 13.8 inches shorter in length than the company’s previous conformal coating system, the PVA650, it has a larger work envelope that can now accommodate a larger head for heavier tools. The robustness of the system has also been enhanced with improved structural and gantry rigidity. The Z-axis has also been upsized for additional rigidity.
PVA has also made the machine more accessible and easy to use. Improvements include a new lift-door that can be effortlessly opened by operators and a keyboard, appropriate for sitting or standing operation, that stores in the unit, keeping it out of the way when not in use.
Integrated consumable storage means needles, small tools and other accessories are always on hand when needed. Access to electrical, pneumatics, fluid delivery components and a new pull-out drawer is easy via a single door in the front.
“This is the most significant overhaul of our product line since introducing the PVA650 in 2008,” says Frank Hart, global sales and marketing manager at PVA. “The conundrum we’ve found is that customers want robust systems that can do more, but take up less space. The Delta 6 coating and dispensing system addresses this concern.”
UV Flood Lamp Cures Adhesives
Cyberbond LLC has released the new CyberFlood10 LED UV-curing flood lamp, a replacement for incandescent UV flood lamps that could save engineers thousands of dollars annually in bulb replacement fees.
The flood lamp is equipped with 10 5-watt LED lamps, each of which emits UV light exclusively at the 395-nanometer wavelength. The lights are arrayed in a mirrored aluminum body, specially designed to maximize output efficiency and dissipate the heat generated by the lamp’s electronics.
The LEDs have a 10,000 hour life—10 times the life of standard bulbs. The LEDs have no performance degradation over time. The PLC-compatible flood lamp turns on and off instantly.
