Increase throughput and maximize accuracy with the fastest dispensing valve on the market
There have been amazing advances recently in automated dispensing technology. The tried-and-true auger valve or progressive cavity pump does a great job, but there are new valves that are literally twenty-times faster: piezo-actuated jet dispensing valves.
Piezo jet valves rely on relatively new piezo technology, dispensing adhesives and other fluids as fast as 1500 Hz continuously, with up to 2000 Hz maximum burst – twice as fast as even a pneumatic jet valve.
The accuracy and resolution of a piezoelectric jet valve like the Techcon TS9800 Series Jet Valve is unmatched, producing shot sizes as small as 0.5 nanoliters.
With the assembly demands of mobile devices, LEDs, consumer electronics, and medical devices, piezo jet valves are the ideal solution for the complexities of modern manufacturing.
Jet Valves vs Contact-Based Valve
One of the big speed advantages of jet valves over contact-based valves is in their movement. Contact-based valve systems must move the dispensing needles down to contact the substrate, then pull back up, reposition, and start again. This repeated up and down motion on the Z-axis takes valuable time. Because the dispensing needle must touch the substrate, additional time is spent with careful height-sensing and repositioning, which also adds to the total dispensing time.
Contactless jet valves eliminate this excess motion by accurately shooting the fluid being dispensed from a fixed location above the substrate. There is no up-and-down motion on the Z-axis. This economy of motion enables a jet valve to dispense 10 – 20 times faster than a contact dispense process.
Piezo Jet Valves vs Pneumatic Jet Valves
When considering a jet valve, be careful to always distinguish between “pneumatic jet valves” and “piezo jet valves.” More common pneumatic jet valves rely on air pressure and mechanics to dispense. Piezo valves, by contrast, use an actuator to create an incredibly precise motion within the valve, dispensing material at much higher speeds.
The process of the pneumatic valve opening, closing, and resetting only takes an extra 20 milliseconds, but those milliseconds add up quickly. This difference makes the piezo jet valve up to twice as fast as a pneumatic jet. For operations looking to maximize throughput, this is an outstanding increase in productivity.
How a Piezo Jet Valve Works
In a piezo jet valve, the fluid to be dispensed is held between the tappet (or piston) and the nozzle. The tappet is connected to a piezoelectric actuator. When an electrical charge is applied to the actuator, it oscillates up and down at an incredibly high rate of speed, generating kinetic energy. This energy forces the fluid to shoot out the nozzle under carefully controlled pressure, forming a perfect bead of material at the target location. This dispensing method is so efficient the valve can complete up to 2,000 cycles per second with 97% accuracy.
Of course, real-world application rates vary, depending on the materials being dispensed, desired shot or line size, and the speed of the valve’s horizontal movement over the substrate.
Other Advantages of Piezo Jet Valves
Another huge advantage of the piezo jet valve is its ability to accurately deliver material in the production of substrates with irregular heights, or where there are hard-to-reach areas. With the fluid being jetted rather than dropped into place, the nozzles can be angled to reach the exact point where the material is needed.
And since the dispensing nozzle does not make contact during the application, there is less likelihood of damaging the product compared to a contact-based valve. The piezo jet valve moves quickly over the substrate, with little to no damage, waste, or downtime.
Fine-Tuning the Settings
The key to taking full advantage of a piezo jet valve is in determining the ideal “recipe.” This is the exact combination of parameters to ensure the precise placement and amount of material dispensed.
Piezo jet valves achieve their small dot sizes using tiny nozzle apertures and finely tuned material pressure and jetting pressure settings. Once all these parameters are determined, the valve is extremely accurate and consistent. But getting to that point may take some trial-and-error.
When shopping for a piezo jet valve, be sure to determine the level of support you will receive from the manufacturer. Each dispensing application is unique, so find a manufacturer that offers some level of hands-on testing of your materials in their valve. This is the best way to ensure their valve will meet your challenges. And confirm they can help quickly fine-tune your controller parameters for your operation.
Controllers for the piezo jet valve have reached the cutting edge as well, offering incredibly precise parameter control. Look for models like the Techcon TS980 Smart Controller with advanced touchscreen controls and intuitive user interfaces, that allow for faster set-up and ease of operation.
The most advanced controllers allow the operator to monitor the system through their smartphone, adjusting settings and troubleshooting from anywhere in the world. These fully connected jet valve systems fit perfectly into the operation of an Industry 4.0 factory, or a facility that is moving in that direction.
Consider the size, weight, and footprint of the valve itself, and how it will fit into the available factory space. Machine integrators take advantage of the piezo valve’s speed and precision by building them into high-end automation equipment, delivering best-in-class results.
Be aware that piezo valves are highly precise pieces of equipment that are very difficult to properly manufacture. The tolerances of the components are extremely tight and producing them within these parameters may be impossible for many parts fabricators. Lower-priced piezo valves quickly develop problems, causing inaccurate dispensing, inconsistent speeds, and other failures that negatively impact productivity and quality. Be sure you are purchasing from a top dispensing valve manufacturer.
Such cutting-edge technology comes at a price, and a piezo valve system is a larger investment than that of a contact-based dispensing system. Still, the lifecycle cost is surprisingly similar to older pneumatic systems, with the piezo assembly rated at around 1 billion cycles. If your manufacturing process would benefit from dispensing at the highest speed and with super-high precision, the investment is worth it.
For more in-depth information on the Techcon TS9800 Series Jet Valve and piezo jet valve systems, see our whitepaper, “Jet Dispensing Technology – Shooting for Perfection“