Optic fiber sensors applications to the wear detection and fracture of cutting tools

Duration of cutting tools has become a very wide field of study as of the beginning of tool machines for series production, since the life of a cutting tool is a very important economic factor in the cut of metals. In all production processes with chip outburst, it is very common that the wear and the fracture or breakages of the cutting tool are present. These factors for minimum that could seem modify the quality of the product. For such a reason one has the necessity of supervising the process and the cutting tool continually; this with the purpose of locating on time changes in the tools, so avoiding the generation of bad surfaces different of these schemed. In this work a method is presented for determining the wear and fractures of a cutting tool in a direct way by means of a fiber optic sensor with high resolution and large bandwidth, used during the manufacturing process. The sensor has been configured with two groups of fibers, distributed in a random fashion. One of the groups works as a light emitter that illuminates the tool, while the other captures the light reflected by the tool surface itself. The light is generated by a photodiode, which does not represent any risk to the health. This technique will allow observing the wear and breakage of the tool in real time while rotating with a high degree of accuracy.