Feed Drive Design for Numerically Controlled Machine Tools

Feed Drive Design for Numerically Controlled Machine Tools
Author: Subash Bhatia
Publisher:
Total Pages: 300
Release: 1971
Genre: Machine-tools
ISBN:

"The various types of feed drive control systems used in numerical control of machine tools have been broadly classified. Further a step by step design has been presented for the feed drive of a numerical contouring control milling machine. The aim has been to develop a consistent strategy for tackling a variety of such problems. Consequently stress has been laid on principles and not on design figures"--Abstract, leaf ii.

Advances in Machine Tool Design and Research 1967

Advances in Machine Tool Design and Research 1967
Author: S. A. Tobias
Publisher: Elsevier
Total Pages: 691
Release: 2016-04-19
Genre: Technology & Engineering
ISBN: 1483154440

Advances in Machine Tool Design and Research 1967, Part I covers the proceedings of the 8th International M.T.D.R. conference (incorporating the 2nd international CIRP production engineering research conference) held in the University of Manchester, Institute of Science and Technology on September 1967. The book covers the accuracy of automatically controlled machine tools; the influence of the rigidity of the machine-workpiece-tool system on the roughness of the machined surface; and the analysis of machine tool structure by computing techniques. The text also discusses sensors of tool life for optimization of machining; pre-set tooling and its application; and system 24, a new concept of manufacture. The design of hydrostatic journal bearings; the computer approach for storage of machinability data and calculation of machining costs and production rates; and a comparison of different measuring and indicating methods for the determination of pitch errors of large precision gears are also encompassed. The book further presents the calibration of tool/work thermocouples, as well as the effect of tool flank wear on the temperatures generated during metal cutting.

Modeling and Control of Linear Motor Feed Drives for Grinding Machines

Modeling and Control of Linear Motor Feed Drives for Grinding Machines
Author: Qiulin Xie
Publisher:
Total Pages:
Release: 2008
Genre: Algorithms
ISBN:

One of the most common goals in manufacturing is to improve the quality and accuracy of the parts being fabricated without reducing productivity. Aiming at this goal, many different manufacturing processes have been developed. Among them, machining plays a major role in increasing product accuracy. As an important machining process, grinding is a vital step that can produce both fine finish and dimensional accuracy for applications in which the workpiece material is either hard or brittle. Currently, the ball screw is the most frequently used setup for grinding machine tool feed drive. However, the existence of transmission components induces wear, high friction, backlash, and also lower system stiffness; therefore, applications of conventional feed drives for high speed and high accuracy machining are very limited. As a promising technology, a linear motor feed drive discards the transmission system; therefore, it eliminates transmission induced error, such as backlash and pitch error, and avoids stiffness reduction as well. As a result, a linear motor drive can achieve both high speed and high accuracy performance. A linear motor feed drive will be subject to external disturbances such as friction, force ripple and machining force. Due to the lack of a transmission unit, the tracking behavior of a linear motor feed drive is prone to be affected by external disturbances and model parameter variations. Thus, in order to deliver high performance, a controller should be capable of achieving high accuracy in the presence of external disturbance and parameter uncertainty. This dissertation proposes a general robust motion control framework for the CNC design of a linear motor feed drive to achieve high speed/high precision as well as low speed/high precision. An application to the linear motor feed drives in grinding machines was carried out. One of the developed algorithms is the HSMC, which combines the merits of a reaching law based sliding mode control and a modified disturbance observer for precision tracking to address the practical issues of friction, force ripple, and grinding force disturbances. Another algorithm presented is ASMC, which combines the reaching law based sliding mode control with adaptive disturbance estimation to achieve an adaptive robust motion control.