Fault Diagnosis: Spectral Analysis of the Vibration Signals in Transfer Press

Fault diagnosis using vibration signals is a major challenge for industrial manufacturing. Obtaining defect information is an important step to make decisions about the maintenance in prognostic and health management systems. Existing studies mostly considers vibration signals collected from elements such as rolling element bearings and hydraulic presses. In this paper, we use the vibration signals obtained from the mechanical transfer press during metal forming process and analyze them from the signal processing point of view. Experimental results reveals that spectral analysis is a good candidate for fault diagnosis and it provides important information about the localized faults embedded in the vibration signals.

Development of Transfer System for Micropress

A micropress system developed by the National Institute of Advanced Industrial Science and Technology (AIST), which uses microdies and strip materials, can machine submillimeter order profiles at 60 shots per minute using a series of in-line press machines. Although this system is an effective machining device for microfabrication, it is disadvantageous in terms of material consumption. In the strip material feeding system, much of the material becomes scrap, which is eventually thrown away after machining. Transfer press processing, a technique involvingmachining precut material to the product size and transferring it between press machines, is an effective method for reducing material waste. Transfer press machining has already been realized at a large scale. However, there have been few attempts to apply the transfer press to micropress machining. In this study, we developed a new microtransfer hand system for the microtransfer press. The developed transfer system can move the material in reverse or half-rotate it for value-added press machining. A test bench was developed for a transfer experiments to check the microtransfer and reverse settings. In the transfer experiments, this system achievedmicrotransfer with a success rate ofmore than 99%. A time-budget schedule was considered to improve the transfer time rate. The relationship between the grasping force of the transfer fingers and the success rate was examined as the first step in analyzing the stability and rapid transfer of work piece.