Desenvolvimento de dinamômetro híbrido aplicado ao 4° eixo de um centro de usinagem

Abstract

In the context of multi-axis machining of mechanical components with free-form geometries, the conventional configurations of the dynamometers (stationary and rotary) are not suitable for operating conditions. This fact occurs due to the mounting of stationary devices limits the workpiece geometry and size, while the assembly of rotating devices is affected by interference in the signal under the conditions of high-speed spindle rotation. In order to propose a solution to this conflicting situation, this research has the objective of developing a hybrid dynamometer, based on strain gauges, mounted in the fourth axis of a vertical machining center and able of measuring axial force and torque. Steps such as conceptual design, engineering analyses, instrumentation, static calibration and natural frequency evaluation were fundamental for manufacturing the device. In addition, the development of a wireless data transfer system have been developed. For this step, it was necessary to create a couple of printed circuit for signal conditioning and amplification, a wireless transmission module and a data processing code aiming the analysis of mechanical loading. The results showed that the conceptual design is appropriated to the dynamometer operating requirements to withstand loads of axial force up to 1 kN and torque 30 Nm, the dynamometer components were in accordance to the tolerances established in design, the performed instrumentation showed suitable to the application, the minimal natural vibration frequency of the device is 602,2 Hz.