Application of Piezoelectric Fast Tool Servo for Turning Non-Circular Shapes Made of 6082 Aluminum Alloy

The paper presents the design and testing of a new servo drive for turning non-circular shapes. The presented solution is based on a commercially available piezoelectric drive unit with a stroke equal to 1000 µm and a resonant frequency of 150 Hz. The device was used in a conventional turning lathe and installed in a tool turret. The performance of the proposed tool was tested while turning multiple non-circular contours from a cylindrical shaft made of 6082 aluminum alloy. The machining accuracy was tested online using a laser sensor and offline with a coordinate measuring machine. The additional aim of those tests was also to verify if the application of an online transducer can allow a confident preliminary assessment of as-machined geometry. The drive positioning accuracy was compensated using 6th order polynomial what resulted in the fabrication of non-circular contours with an accuracy of no less than 39.8 µm when operating below the limit frequency of the drive (<9 Hz). It was found out that the deviations of the profile from ideal geometries increase linearly with frequency when turning at higher than the limit frequency.

Experimental Analysis of a Novel Piezoelectric Jetting System for Micrograms Deposition in Electronic Assemblies

Over the past ten years, there has been an exponential growth in innovations and designs to offer cutting edge electronic devices that are smaller, faster, with advanced features built in. The existence of smartphones, wearable devices, tablets, etc., is the evidence of these advancements. Original equipment manufacturers are looking for processes in electronic assemblies that can offer high‐speed, high accuracy, and fine droplet mass deposition to address the challenges of product miniaturization, high-density component packaging, and complex designs. This work presents a novel piezoelectric-driven jetting system that is designed to dispense small droplet masses with high accuracy and speed. The system is referred to as “novel” because, in the contact style jetting arena, the piezoelectric drive assembly for use to drive the motion of the piston assembly at high frequencies (up to 500 Hz) is new; furthermore, the piston motion tracking feature is patent pending of. Using a split-plot design of experiments (DOE) model, the jetting system is studied to understand the influence of critical designs introduced and to further review the smallest droplet mass possible to reliably dispense. This experimental analysis uses some of the widely used adhesives in the electronics assembly applications.