Measurement of Non-rigid Tools Action Force During Finishing

The purpose of the research was to design a device (dynamometer) for measuring the action force on work surface (cutting force) during the finishing process with non-rigid tools such as flap wheels, mechanical brushes with metal and nonmetal fibers, or using jet processing with various fillings - sand, grinding materials, metal shot, glass microbeads, etc. The information about force level is used, for example, to select a tool or a method for finishing of thin-walled parts or edges as well as for determination of rational processing modes of the method selected. This device considers special features of action force of some tools and methods: distributed type of loads; rapidly changing force intensity; possibility of rocking sensitive device element; furthermore, different level of loads needs increased sensitivity on the one hand, and on the other hand, the universality of the device. The proposed device provides measuring constant, inconstant and harmonic loads in wide range as well as measuring concentrated and distributed forces with high accuracy. It allows registering information in real time, saving and processing data in a comfortable form. For example, the proposed dynamometer was used to measure action force of brush rotary disc polymer-abrasive tools on work surface. The tools based on polymer-abrasive fiber are used for finishing parts of complex profile, for trimming, cleaning, deburring, etc. They also have a light hardening effect. The results of research determined that force is 20...100 H depending on processing modes and tool options, therefore polymer-abrasive brushes can be used for thin-walled parts.