• Journal of the Korean Society for Precision Engineering
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• v.16 no.11
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• pp.47-54
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• 1999

Tool wear is one of major causes occurring defectives in NC machining. In this paper we developed an automatic tool compensation system for the NC lathe machining. The system compensates machining error without any help of operators whenever the specification of a part is out of a tolerance. The configuration of the automatic compensation system consists of a NC lathe, an autoloader, a sensor, and a PLC. The system is operated as follows. A workpiece loaded by the autoloader is machining on the NC lathe. Once the workpiece is machined to be turned to a part, it is moved onto the sensor to be measured. If the sensor detects a part out of tolerance, a tool compensation is made in the NC controller. The system gives a help in increasing the productivity by reducing occurrence of defective parts as well as by eliminating time for the tool compensation. Besides the productivity increase, the system calculates cumulative usage time of the tool and notices the tool replace time to a worker by an alarm signal. A case is introduced to show that the system can be applied effectively in a shop.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.11 no.5
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• pp.93-99
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• 2002

In general, manufacturing error is originated from bad material, machine tool defection and tool breakage. When the manufacturing process is stable, the most of error come from the tool wear. In common on-machine measurement teaching probe and touch sensor are widely used however in this paper the electric touch point type automatic tool compensation system is developed the performance of it is validated and effective operating is proposed.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.04a
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• pp.371-375
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• 2001

The tool wear that is developed by long-term machining in mold manufacturing with machining center makes a severe influence to the accuracy and the surface roughness. In this reason, tool-wear supervising system which has guaranteed high accuracy and high speed is needed to improve the measurement quality. Touching probe and touch sensor are widely used to measure the tool profile at on-machine measurement. In this paper, using the newly developed electric touch point measuring system, the Automatic Tool Compensation System is developed to correct the error of tool diameter resulted from the wear, and the operating method of this system is also provided.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.10 no.4
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• pp.48-54
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• 2001

The tool wear that is developed by long-term machining in mold manufacturing with machining center makes a severe influence to the accuracy and the surface roughness. in this reason, tool-wear supervising system which has guaranteed high accuracy and high speed is needed to improve the measurement quality. Touching probe and touch sensor are widely used to measure the tool profile at on-machine measurement. In this paper, using the newly developed electric touch point measuring system, the Automatic Tool Compensation System is developed to correct the error of tool diameter resulted from the wear, and the operating method of this system is also provided.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.100-105
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• 2002

In general, manufacturing error originated in bad material, machine tool defection, tool defection, and tool breakage. When the manufacturing process is stable, the error is come from the tool wear. In common on-machine measurement, teaching probe and touch sensor are widely used, however in this thesis the automatic tool compensation system using electric touch point measuring system is developed and evaluated, and effective operating is proposed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.445-449
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• 2001

The tool wear that is developed by long-term machining in mold manufacturing with machining center makes a severe influence to the accuracy and the surface roughness. In this reason, tool-wear supervising system which has guaranteed high accuracy and high speed is needed to improve the measurement quality. Touching probe and touch sensor are widely used to measure the tool profile at on-machine measurement. In this paper, using the newly developed electric touch point measuring system, the Automatic Tool Compensation System is developed to correct the error of tool diameter resulted from the wear, and the operating method of this system is also provided.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.6 no.4
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• pp.57-64
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• 2007

In the recent years, development of machine tool with high speed feeding system have brought a rapid increase in productivity. Practically, thermal deformation problem due to high speed is, however, become a large obstacle to realize high precision machining. In this study, therefore, the construction of automatic error compensation system to control thermal deformation in high speed feeding system with real time is proposed. To attain this purpose, high speed feeding system with feeding speed 60mm/min is developed and experimental equation for relationship between thermal deformation and temperature of ball screw shaft using multiple regression analysis is established. Furthermore, in order to analyze thermal deformation error, compensation coefficient is determined and thermal deformation experiments is carried out. From obtained results, it is confirmed that automatic error compensation system constructed in this study is able to control thermal deformation error within $15{\sim}20{\mu}m$.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.1
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• pp.69-77
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• 1998

Linear displacement accuracy is one of the most important factors that determine machine tool accuracy The laser interferometer has been usually recommended for the measurement of linear displacement accuracy. In this paper, microcomputer aided measurement and compensation system has been developed for the pitch error in a CNC machine tool. For accurate pitch error calculation. the analysis code for the pitch error has been also implemented according to the international standards (ISO). The PC based automatic compensation system for the pitch error is also implemented. A new algorithm for calculating optimum value for pitch error compensation is proposed, minimizing the deviation at each target points. The development system has been applied to a practical CNC maching center and the performance has been demonstrated.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.04a
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• pp.225-230
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• 2004

A cold ＆ hot rolling coil production line of iron nill consists of a kind of coherent automatic process, but an automatic labelling process still had technical difficulties in the automation of its process. The reason for difficulties in building an automatic process is that quantitative data for each rolled coil from every shipping is not easy to receive from the previous process. it is not possible to apply for a general and simple purpose robot that is actually worked through a taught position to the process because the size and direction of the coi1 has differed on every shipping. From these reasons. we introduce a robot vision system to accept an expected variable situation and to ensure the stability and flexibility of the process. This paper examines a study applied for similar cases and finds the position and direction of relied coil using the moment invariant algorithm proposed by Hu. In addition. the camera calibration and position error compensation algorithm is applied by the analysis of the relationship of transition in a space coordinate system. The construction of a robot vision system proposed by this paper is a more intellectual system than that of the automatic labelling system. which is already used to the Daihen steel nill of NEW JAPAN steel mill co. Ltd in Japan, and shows a better independent operation in the field of production.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.297-302
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• 1997

Linear displacement accuracy is one of the most important factors that determine machine tool accuracy. The laser interferometer has been usually recommended for the measurement of linear displacement accuracy. In this paper, microcomputer aided measurement and compensation system has been developed forthe pitch error in a CNC machine tool. For accurate pitch error calculation, the analysis code for the pitch error has been also implemented according to the international standards(ISO). The PC based automatic compensation system for the pitch error is also implemented. A new algorithm for calculating optimum value for pitch error compensation is proposed, minimizing the deviation at each target points. The development system has been applied to a practical CNC maching center and the performance has been demonstrated.