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­^¤åºK­n The purpose of this thesis is to propose the rules for designing a grinding system with nano-order of relative vibration. Such a system is aimed to perform the ductile-regime grinding for brittle materials. The study will examine the influence of the structure stiffness, damping, and mass of the grinding system on the relative vibration between grinding wheel and work. Accordingly, the design rules will be proposed. To analyze the relative vibration, the radial and axial models for a grinding system were built. The trends of relative vibration between grinding wheel and work were then analyzed under three kinds of vibration sources. Because of the nonlinearity of system equations, the 4th order Runge-Kutta numerical method was used to calculate the solutions. In addition, the genetic algorithm was used to search an optimum design. From the analysis, several design rules for grinding system, which can minimize the relative vibration, were proposed.

The diploma thesis focuses on a conceptual design of a surface grinding machine. Aim of this work is to analyze current products and create a new design and ergonomic proposal. Result of this work is a concept of a surface grinding machine, that is defined by its progressive form and intuitive operation. The thesis brings a vision and a new solution for a current machine tool design from an ergonomic and technical perspective.

The ceramic ball bearing has been used to exact machine for its good properties such as heat-resistant, corrosion-resisting, and wear-resisting. The old grinding methods of ball bearing spend much time and power. Although the magnetic fluid grinding method economizes time, but cost much money. This study research the effects of spindle speed, grit size, load, and the material of float-ring and fixed-ring on the grinding characteristics by using a new ultra-precision ball grinding machine which developed by our lab. Search the optimum operating conditions of this machine for the requirement of industrial circles. Experimental results show that the converge rate of the saturated value for the sphericity, surface roughness (Ra), and the removal rate are increased with increasing spindle speed, grit size, or load. The sphericity and surface roughness (Ra) are increased when spindle speed, grit size, or load is increased. The sphericity and surface roughness (Ra) are increased with increasing removal rate in using the same grit size and load. Under a certain operating parameter of grinding process, the mean diameter and removal rate are decreased with increasing grinding time. The sphericity and surface roughness (Ra) are better when using the plastic than the float-ring and fixed ring of aluminum, but its removal rate is lower than aluminum¡¦s. First, let the average sphericity achieve saturated value by using diamond grind disk to grinding the Al2O3 ceramic ball. Then, the optimum sphericity can achieve 0.7£gm and the surface roughness (Ra) can achieve 0.1£gm by using the B4C grits of 0.5£gm to grinding.

Mechanical grinding processes is the most popular way to fabricate the endface of optical fibers, although there are some other methods like chemical etching and leaser machining. Mechanical grinding has its uniqueness in cases of grinding Conical-Wedge-Shaped Fiber Endface¡]CWSFE¡^, polygon-cone-shape fiber endface and fiber endface with double-variable curvatures. Despite Mechanism Design Lab of National Sun Yat-sen university has successfully developed Unsymmetrical Fiber Endface Grinding Mechanism and Torque-Control Fiber Endface Grinding Mechanism in NSC 94-2212-E-230-005 and NSC 95-2221-E-230-020, it still face difficulties when fabricating the fiber endface with double-variable curvatures due to the mechanism constraints. In this study, the focus are concentrated on both the designing and implementing of a mechanism for grinding optical-fiber endface with double-variable curvatures, which controls Material Removal Rate by simultaneously and periodically adjusting the relative positions, as well as the normal pressure between the fiber endface and the grinding film. This study is composed of first, the reviewing the anterior references, both the papers and the patents, and then a series of engineering design methods, which involve the design requirements and constraints, conceptual design, evaluating alternatives, detail design, assembly and calibration. The mechanism, the research result, and those needed to be ameliorated will be demonstrated in the conclusion and discussion part, so as to offer the investigating direction in the future. It¡¦s believed that the grinding machine system developed in this study can be successfully applied to fabricating optical fiber lenses as well as different types of micro probes , micro electrodes, and micro spectroscopefors for other applications, with little adjustment of the jig and ferrule of this machine .

The mechanical grinding processes is the most popular way to fabricate the end face of optical fibers, although there are some other methods like chemical etching and leaser machining. In cases of fabricate the wedge type and wedge-cone type optical fiber end faces, the mechanical grinding is the typical way. Professor Y. C. Tsai¡¦s research group has successfully fabricated the optical fiber with elliptical-cone-type end-face in a single grinding process by adopting a mechanism with eccentric mass on the commercial optical fiber grinding machine. In this study, a torque motor is equipped on the commercial optical fiber grinding machine for controlling the normal pressure between the optical fiber and the grinding film during the grinding process. While the optical fiber rotating, the normal pressure, as well as the material removed rate and the final shape of the optical fiber, can be controlled in different periodical mode shapes by applying different voltages with different periodical mode shapes. The merit of this system is its capability of fabricating fiber with elliptical-cone-shape and polygon-cone-shape (polyhedron-tip) end faces in a single grinding process that will increase the efficiency and the accuracy of grinding. It is believed the grinding machine system developed in this study can be successfully applied for fabricating the optical fiber lenses as well as different types of micro probes for other applications.

Decisions has in recent years become more challenging, today the environment is changing in an exponentially increasing pace. This is not the only challenge with modern decision making, there are also: multiple criteria, intangibles, risk/uncertainty, long term implications, interdisciplinary input, pooled decision making, value judgment and unintended consequences. The purpose of the study is to create a model that provides a structured way of comparing and evaluate different alternatives for a decision making process, regarding profitability in a production station. The developed decision support model has its roots in the Plan-Do-Check-Act (PDCA) improvement cycle, where the planning phase has been modified. The planning phase of the model consists of seven steps that identify the process and perform a cost-break-down structure of the cost related to the process. This enables weights to be created and compared to each other and finally against other investment alternatives. This facilitates a structured approach, which minimizes some of the risks that can be involved in decision making and is further decreased by discovering uncertainties. The decision making model have been tested on two different production processes in a manufacturing company that is considering improvement investments.

This work describes the construction of polymer - concrete frame of a machine tool. In particular it deals with the proposal of cast iron frame for the surface grinding machine BHP from the company KMS Brno, which should at all point replace the original cast iron frame of the same machine. The whole work is divided into two sections. First section consists of the research including a brief mention of the grinding technology in the reference to the construction of the frame of the grinding machine. Further the work deals with the theoretical knowledge regarding construction of frames of the machine. Finally it describes issues related to the technology of polymer – concrete and the production technology of parts from this material. Second section of the work consists of an engineering proposal of polymer – concreted frame considering the requirement of the main functional dimensions related from the structural measures. Subsequently the system approach and the principals for transition to the polymer – concrete construction of the grinding machine are made. The work concludes with the analysis and comparison of the two concepts (cast iron frame and polymer – concrete) in the terms of the Finite element method.