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Air Pressure is the Cause of Erratic Fluid Dispensing

Multiple firefights have been attempted to try and combat the erratic fluctuation of air supply from compressors in the fluid dispensing industry. The first firefight focused on the syringe and piston. Both syringe and piston designs were altered several times in an attempt to extinguish the fire.

The second firefight focused on the dispense tip. Restrictions at the end of the syringe barrel luer and restrictions inside the dispense tip were targeted. Several new styles of dispense tips were developed as an attempt to extinguish the fire.

The third firefight focused on the air compressor and timing circuit as the cause of erratic dispensing. Analog time was replaced by digital timers in the hope of better air solenoid performance. Filtration systems were added in an attempt to stop moisture contamination of control boxes, syringes, and the assembly fluid.

Achieving little results with moisture and time control the firefighting shifted to volumetric displacement. As the space between the piston and air source gets larger the time of the dispense cycle and force of the air pressure must increase otherwise the dispense dot gets smaller as the syringe empties. This problem requires hourly adjustments of the air pressure and time settings causing a high level of frustration with the operators.

The volumetric displacement firefight involved air pressure compensation. Pressure sensors are used to adjust air pressure and software to make hourly adjustments to air pressure for the operator. Automating hourly adjustments is a classic example of how firefighting byproducts of a root cause problem can waste time and money. Automating a problem is not a solution. And the firefighting goes on and on and on. By ignoring the root cause of the problem-air pressure- hundreds of thousands of dollars were lost firefighting byproduct problems.

Fishman® Corporation learned from the 35 year firefighting model provided by the air dispensing manufacturers. Applying the Ishikawa diagram the Fishman® engineering team was able to clearly identify the root cause of the 35 year firefighting disaster- air pressure. By eliminating the root cause they could eliminate all the byproduct problems and finally raise fluid dispensing system performance to exceed manufacturers’ desires and expectations.