The integrity of machined holes depends on many parameters, some which are related to the cutting tool (geometry, coating, material). Other influential parameters machining process variables (spindle speed, feed rate, workpiece material), all can affect quality hole and drilling induced damage its surface. This study investigates effect uncoated tools four types coatings (TiN-, TiCN-, TiAlN-, T...

The spindle assembly checkpoint prevents separation of sister chromatids until each kinetochore is attached to the mitotic spindle. Rodriguez-Bravo et al. report that the nuclear pore complex scaffolds spindle assembly checkpoint signaling in interphase, providing a store of inhibitory signals that limits the speed of the subsequent mitosis.

INTRODUCTION Recently, a milling for die using a small end mill of diameter less than 1 mm is increased, because sizes of plastic mold parts such as connectors for an IT and an electronics becomes micro extremely. In general, a tool life is long and a good cut surface is obtained as a cutting speed is high. A speed-increasing spindle, which is attached to a shank may be used to increase the cut...

For the purpose to facilitate development of high-speed Spindle Units (SUs) running on rolling bearings, we have developed a beam element model, algorithms, and software for computer analysis of thermal characteristics of SUs. The thermal model incorporates a model of heat generation in rolling bearings, a model of heat transfer from bearings, and models for estimation of temperature and temper...

The temperature field distribution has a significant influence on structural performance, thermal deformation, and error compensation. To improve the prediction accuracy of spindle system, comprehensive model considering contact resistance (TCR) interfaces was established to analyze performance high-speed system in present work. An elastoplastic used calculate contacting areas loads interfaces,...

Abstract Bearingless motorized spindle is a kind of structure that combines bearingless motor with spindle. It has the advantages and motor, which can further improve speed machine tool However, its complex electromechanical coupling relationship between subsystems make it difficult to control operation process accurately. In this paper, voltage decoupling method used decouple torque suspension...

High-speed electric spindle is an important part of computer numerical control (CNC) machining equipment. The thermal displacement generated by the during operation main reason that affects stability and accuracy spindle. Compensating error high-speed can effectively improve CNC machining. Improve equipment processing performance. Therefore, it particularly to establish prediction model. Taking...

This paper presented a new grinding method in relation to the focus of high-speed precision machining for non-circular parts. We designed and integrated a set of grinder NC system, refitted an experimental NC grinder and researched into the control core of the NC grinder-open Programmable Multi-Axis Controller (PMAC), linear motor feed unit and high-speed electrical spindle unit. The numerical ...

In view of the unstable cutting problem in the process of high speed milling hardened steel. Conduct experiment of the stability of machine tool and high speed milling cutter. The machine tool spindle vibration spectrum and vibration acceleration signal under the condition of different centrifugal force were detected. Obtained the critical speed of security and stability cutting of milling cutt...