METHOD AND DEVICE FOR REDUCING TEMPERATURE-RELATED MEASUREMENT DEVIATIONS IN PARALLEL MEASUREMENT SYSTEMS

摘要

It is known per se that differences in temperatures lead to an expansion of machines, especially of large tool machines. Expansions are almost always asymmetrical. This creates problems especially for machines with gantry axles because the two parallel longitudinal measurement systems for the gantry axle are displaced against each other as a result of the different expansions of the machine. The gantry axle can jam because the measured values of the longitudinal measurement systems are used for controlling the drives for moving the gantry axle. According to the invention, the measurement systems or parts thereof are not directly connected to the machine. Thus, a geometrical change in the machine cannot cause the measurement systems to be displaced against each other. The displacement of the measurement systems against each other is compensated instead by determining the geometrical change in both the machine and the measurement systems. Errors in the measured values are compensated according to a mathematical model corresponding to said geometrical change. In order to determine the temperature-related geometrical change in the machine, additional measuring devices are arranged on a temperature-stable connecting bridge in such a way that said measuring devices determine the geometrical change in the machine in the end areas of the measurement systems.