The invention relates to an on-line control method of
liquid nitrogen injection quantity for ultra-low temperature cooling
processing. The on-line control method of the
liquid nitrogen injection quantity for ultra-low temperature cooling
processing comprises the following steps that firstly, a relation model between
cutting process parameters and the
liquid nitrogen injection quantity is constructed, and the model is placed into an on-line controller for ultra-low temperature
processing liquid
nitrogen injection. The controller can regulate and
control material characteristics, tool parameters, an optimal
cutting temperature and heat dissipation ratio coefficients input by a central control computer of a liquid
nitrogen supply device based on the collected
cutting process parameters of a
machine tool
numerical control processing
system, and expected liquid
nitrogen injection quantity is determined by calling the
relational model and a parameter
database; and meanwhile, the controller collects the temperature of a cutting area online through a
thermocouple fixed in an internal jet type
cutting tool to feedback and adjust actual liquid nitrogen injection quantity to change within a certain range, so that the cutting area is in an optimal cutting temperature range, the processing quality of parts is ensured, and the service life of the
cutting tool is prolonged. The on-line control of the liquid nitrogen injection on-line quantity is achieved according to the heating condition of cutting processing, optimization iteration time is short, and accurate control over the temperature of the cutting area can be quickly realized.