Arrangement for sensing elastic deformation in a tool stem in a machine tool

An arrangement for detecting elastic deformation of a shaft carried by a machine tool having a cutting bit, comprising an optical fibre section mounted in or on the shaft at a distance from a neutral bending axis of the shaft in the longitudinal direction of said shaft;

• wherein the optical fibre section, which follows the elastic deformation of the shaft, extends parallel with and at a constant distance from the neutral bending axis of said shaft so that elongation of the optical fibre section forms a measurement of bending of the shaft in an axial plane that includes the optical fibre section;
• wherein the optical fibre section has at least two longitudinally spaced partial reflection means;
• determining means connected to the optical fibre section for determining a chance in distance between the partial reflection means in the optical fibre section, said change in distance providing a measurement of shaft curvature;
• and means for compensating for the influence of temperature on the change in distance between said partial reflection means, wherein the optical fibre section extends to a cutting tool holder on the shaft and is provided with a grid in the vicinity of the cutting bit, wherein the grid is adapted to be influenced by a temperature of or prevailing in the vicinity of the cutting bit, so as to enable the bit temperature to be followed via the optical fibre section and the grid optically.

An arrangement for detecting elastic deformation of a shaft carried by a machine tool having a cutting bit, comprising an optical fibre section mounted in or on the shaft at a distance from a neutral bending axis of the shaft in the longitudinal direction of said shaft;

• wherein the optical fibre section, which follows the elastic deformation of the shaft, extends parallel with and at a constant distance from the neutral bending axis of said shaft so that elongation of the optical fibre section forms a measurement of bending of the shaft in an axial plane that includes the optical fibre section;
• wherein the optical fibre section has at least two longitudinally spaced partial reflection means;
• determining means connected to the optical fibre section for determining a change in distance between the partial reflection means in the optical fibre section, said chance in distance providing a measurement of shaft curvature;
• and means for compensating for the influence of temperature on the change in distance between said partial reflection means, wherein the shaft includes vibration damping means having setting means;
• and control means which processes information relating to elastic deformation of the shaft and assigns setting values to the setting means or to control said setting means.

An arrangement for detecting elastic deformation of a shaft carried by a machine tool having a cutting bit, comprising an optical fibre section mounted in or on the shaft at a distance from a neutral bending axis of the shaft in the longitudinal direction of said shaft;

• wherein the optical fibre section, which follows the elastic deformation of the shaft, extends parallel with and at a constant distance from the neutral bending axis of said shaft so that elongation of the optical fibre section forms a measurement of bending of the shaft in an axial plane that includes the optical fibre section;
• wherein the optical fibre section has at least two longitudinally spaced partial reflection means;
• determining means connected to the optical fibre section for determining a change in distance between the partial reflection means in the optical fibre section, said chance in distance providing a measurement of shaft curvature;
• and means for compensating for the influence of temperature on the chance in distance between said partial reflection means, control means which processes information relating to elastic deformation of the shaft and assigns setting values for working parameters of the machine tool associated with said shaft, or to control working parameters of the machine tool associated with said shaft.

An arrangement for detecting elastic deformation of a shaft carried by a machine tool having a cutting bit, comprising an optical fibre section mounted in or on the shaft at a distance from a neutral bending axis of the shaft in the longitudinal direction of said shaft;

• wherein the optical fibre section, which follows the elastic deformation of the shaft, extends parallel with and at a constant distance from the neutral bending axis of said shaft so that elongation of the optical fibre section forms a measurement of bending of the shaft in an axial plane that includes the optical fibre section;
• wherein the optical fibre section has at least two longitudinally spaced partial reflection means;
• determining means connected to the optical fibre section for determining a chance in distance between the partial reflection means in the optical fibre section, said change in distance providing a measurement of shaft curvature;
• and means for compensating for the influence of temperature on the change in distance between said partial reflection means, wherein the partial reflection means form parts of a grid structure, wherein change in the electromagnetic signature of the grid is sensed and determined by determining means for forming a measurement of shaft curvature at the grid.

An arrangement for detecting elastic deformation of a shaft carried by a machine tool having a cutting bit, comprising an optical fibre section mounted in or on the shaft at a distance from a neutral bending axis of the shaft in the longitudinal direction of said shaft;

• wherein the optical fibre section, which follows the elastic deformation of the shaft, extends parallel with and at a constant distance from the neutral bending axis of said shaft so that elongation of the optical fibre section forms a measurement of bending of the shaft in an axial plane that includes the optical fibre section;
• wherein the optical fibre section has at least two longitudinally spaced partial reflection means;
• determining means connected to the optical fibre section for determining a change in distance between the partial reflection means in the optical fibre section, said chance in distance providing a measurement of shaft curvature;
• and means for compensating for the influence of temperature on the change in distance between said partial reflection means, wherein the partial reflection means are comprised of grids or mirror arrangements that are mutually separated along the optical fibre section, wherein a change in distance therebetween forms a measurement of shaft curvature therebetween.