Real-time online detection and compensation device for thermal elongation deformation error of boring spindles of numerical control machine tool

Abstract

The invention discloses a real-time online detection and compensation device for thermal elongation deformation error of boring spindles of a numerical control machine tool and aims at mainly solving the problems that the machining precision of an existing numerical control machine tool is poor caused by thermal elongation deformation of the boring spindle. The real-time online detection and compensation device is characterized by comprising detection shaft sleeves made of materials with a low thermal expansion coefficient, a positioning disc, detection rings, transfer screws, displacement sensors, sensor mounting bases, a PLC (Programmable Logic Controller) simulation input module, a temperature compensation functional module of a numerical control system and a ball screw pair, wherein each detection shaft sleeve is arranged inside the corresponding boring spindle and outside a broach rod; the front end of each detection shaft sleeve is rigidly coupled with the corresponding boring spindle through the positioning disc; the rear end of each detection shaft sleeve and the corresponding detection ring can freely move relative to the corresponding boring spindle in the axial direction; the thermal elongation deformation error is detected by the displacement sensors and is fed back to the numeric control system; the real-time online detection and compensation of the thermal elongation deformation error of the boring spindles are realized by the temperature compensation function of the numeric control system. After the device and the detection and compensation method are applied, the machining error of the numeric control machine tool caused by the thermal elongation deformation error of the boring spindles can be greatly reduced, the preset control precision of the machine tool is guaranteed, and better economic and social benefits are achieved.

Description

technical field [0001] The invention relates to a real-time on-line detection and compensation device for the thermal elongation deformation error of a boring shaft of a numerically controlled machine tool, belonging to the technical field of precision machining machine tools. Background technique [0002] During the use of the machine tool, a large amount of heat will be generated due to friction between the moving parts. At the same time, heat exchange will occur between the machine tool and the external environment, which will cause thermal expansion of each part. Under the action of various constraints, it will eventually lead to various Inaccuracies in the position and attitude of moving parts, resulting in thermal errors. Thermal errors account for a considerable proportion of the overall error of the machine tool. Studies have shown that the machining error caused by thermal deformation in precision machining accounts for 40-70% of the total machining error, and has b...

AI Technical Summary

Problems solved by technology

Due to the influence of heat generated by the high-speed rotation of the spindle, the boring shaft will produce large thermal deformation, especially the thermal elongation error in the feeding direction of the boring shaft is more obvious, which seriously affects the machining accuracy, stability and application range of the machine tool

For example, when installing a milling cutter on a boring shaft to mill a large plane, due to the long interval between two millings, the thermal elongation of the boring shaft during this period is relatively large, and its thermal elongation cannot be measured under the current conditions , and uncontrollable, it will produce more obvious tool marks, so that the milled plane does not meet the processing technology requirements of the parts, resulting in a high scrap rate, which has become one of the key issues that every host manufacturer needs to solve urgently

[0004] At present, there is no effective prevention and solution for the thermal expansion and contraction deformation of the boring shaft due to the change of the temperature field. Adding a cooling device to reduce the temperature of the boring shaft indirectly, or improve it by preheating with an idle stroke to balance the temperature field before the formal cutting process

However, due to the limited effect of the cooling jacket device, the problem of thermal elongation of the boring shaft cannot be completely solved, and the thermal elongation error of the boring shaft will change with the change of working conditions and ambient temperature.

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