Method of monitoring parameters of coating material dispensing systems and processes by analysis of swirl pattern dynamics

摘要

A method of monitoring and/or controlling the motion of a moving coating material dispensing pattern or fiber is provided with a monitor that senses a medium such as sound, light or other form of energy near the space between the dispensing device nozzle and a substrate, and a monitoring signal is generated. Information relating to the pattern motion is extracted, and an output signal is generated representative of characteristics of the motion of the pattern in the space. One or more transducers are used to extract the information, which is analyzed, preferably by comparison of a frequency spectrum of the signal with a spectrum of standard signal, to detect deviations in the system operation from desired criteria. Optionally, the output signal is used to control parameters of the system. In another embodiment, plural spaced transducers detect the phase or orientation of the moving pattern and remove background noise, by inverting, summing, multiplying, and otherwise combining the signals. The invention is useful for detecting malfunctions of the system components, for real-time closed loop control of the process, and for quality control inspection of dispensing device components during manufacture.