Innovative Machine Tool Research Articles

Features and Characteristics of Motorized and Non Motorized Milling Spindles

The Cutting process used in milling is one of the most common type of industrial machining methods. Similar to traditional milling spindles, the motor driven spindles are fitted with an integrated motor, thereby eliminating belts and gears for the transmission of power from the motor to the cutting tools. The innovative machine tools should be highly characterized systems in order to retain the necessary precision, efficiency and reliability. To satisfy their end user's reliability and availability requirements, both the spindle system (Tool/Tool-Holder/ Spindle) and motor tool system need to be configured for their usability and output results. However, the quality of a control device in industrial practice is greatly affected by the spindle cutting output and its reliability. The motor spindles are nothing but the rotating drive shafts which acts as axes for cutting force tools or in machining process for holding cutting instrument. Hence the spindles are one of the important factor in machining tool process and productivity, as these are used to produce parts as well as machines that produce components, which in turn have a significant impact on production levels and quality of products.

Statistical Capability Study of a Helical Grinding Machine Producing Screw Rotors

Screw compressors depend for their efficiency and reliability on the accuracy of the rotors, and therefore on the machinery used in their production. The machinery has evolved over more than half a century in response to customer demands for production accuracy, efficiency, and flexibility, and is now at a high level on all three criteria. Production equipment and processes must be capable of maintaining accuracy over a production run, and this must be assessed statistically under strictly controlled conditions. This paper gives numerical data from such a study of an innovative machine tool and shows that it is possible to meet the demanding statistical capability requirements.

Solutions for Sustainable Machining

The manufacturing industry contributes over 19% to the world's greenhouse gas emissions (U.S. Energy Information Administration, 2008, “Rep: Annual Energy Review 2008,” Report No. DOE/EIA-0384; Diaz et al., 2010, “Environmental Analysis of Milling Machine Tool Use in Various Manufacturing Environments,” 2010 IEEE International Symposium on Sustainable Systems and Technology.) and 31% of the total energy consumed annually in the U.S. (Herzog, T., 2005, “World Greenhouse Gas Emissions in 2005,” World Resources Institute, Washington, DC 2; Diaz et al., 2010, “Environmental Analysis of Milling Machine Tool Use in Various Manufacturing Environments,” 2010 IEEE International Symposium on Sustainable Systems and Technology.). There is therefore an increasing demand for sustainable solutions for the production technology industry. At the Technische Universitat (TU) Berlin, Germany, a collaborative research center (CRC) is focusing on new solutions for the sustainable machining of high performance alloys, with developments from machine tool frames to cutting tool technology being undertaken. An innovative machine tool concept with a modular frame, which allows a high level of flexibility, has been developed. Furthermore, add-on upgrading systems for older machine tools, which are particularly relevant for developing countries, have been developed. These systems allow the accuracy of outdated machine tools to be increased, thus making the machine tools comparable to modern systems. Finally the cutting process also requires solutions for dry machining, as the use of cooling lubricant is environmentally damaging and a significant cost contributor in machining processes. Two solutions are being developed at the TU Berlin: an internally cooled cutting tool and a heating concept for ceramic tools to allow dry machining of high temperature alloys, for example, for the aerospace industry.

Precision milling method for face-gear by disk cutter

In order to accelerate the engineering application of face-gear, a precision milling method for face-gear by disk cutter is provided in this paper. Based on the principle of face-gear drive, the principle of face-gear milling by disk cutter is analyzed, and the mathematical model of the disk cutter is presented according to the meshing principle. Taking the milling needs into account, an innovative machine tool is developed, and the movement control method of face-gear milling by the disk cutter on the special machine tool is provided. For the comparison of tooth surface accuracy, the equation of face-gear tooth surface is calculated, and the 3D model of face-gear is established based on CATIA software. To verify the feasibility of the method, a simulation of face-gear milling is put forward based on VERICUT software. To optimize machining parameters and improve the machining accuracy, an error analysis model of face-gear milling is established, and the corresponding error influence rule caused by installation and movement parameters is obtained. In order to verify the theory, the experiment is carried out, and the completed specimen is detected by coordinate measuring machining (CMM). Finally, the processing parameters are amended according to the detection results and the error influence rule, and the maximum dimensional deviation value of specimen face-gear tooth profile is reduced from 181.2 to 30.4 μm. The result shows that the method of errors amendment can improve processing accuracy, and the generating milling method by disk cutter is an effective approach to achieve the precision face-gear.

Contemporary equipment design

Trends in the development of industrial machines and corresponding design methods are considered. The problems to be solved in the design of traditional and innovative machine tools are discussed. Approaches to meeting the operational requirements on industrial machines are outlined.

A Framework for Systematizing Machine Tool Engineering

The demand for machine tools with accuracy on a nanometer scale has been increasing in a wide range of industries. Machine tools have been called “mother machines” in that they produce various other devices. In order to meet the requirements of industry, numerous research activities have been conducted to develop various technologies related to machine tools. However, there are only few established technologies in spite of the machine tool industry’s long history. A new approach to systematizing machine tool engineering is playing an increasingly important role in the development of innovative machine tools. This paper presents a conceptual framework for systematizing machine tool engineering. Future evolutionary trends in machine tool engineering are also described.

The Task of Research on Trussed Type Machine Tool

An innovative machine tool of trussed type is introduced in this paper. It has many advantages such as light weight, rapid traverse speed and so on. But as a new type of machine tool in structure, investigation of it is not enough and further efforts are still needed. With the development of manufacturing technology, higher and higher demands of machine tool are required, and more efforts should be put on research in order to reinforce the performance of it, such as the static and dynamic stiffness, the dynamic performance and natural frequency, frequency characteristic, and so on.

Prediction of the dynamic behaviour of machine tools during the design process using mechatronic simulation models based on finite element analysis

Increased productivity, higher velocities and acceleration for feed and cutting motions are requirements for innovative machine tools. At the same time the production process must achieve reduced form and position deviations of the work-piece. Therefore knowledge of the dynamic behaviour of machine tools during the design process is essential to develop high-performance machines. Using finite element analysis and mechatronic simulation, taking the mechanical, electrical and control systems into account, is the first step for optimisation. Developing the control parameters using these simulation techniques is one of the major steps in detecting the mechatronic characteristics. This paper presents a method for developing the control parameters concerning tool to work-piece deviations of mechatronic simulation models including disturbance variables. As an example a 2-axis CNC test stand for feed drive axes will be visualised with its simulation and measurement results in the time and the frequency domain.

Simulation of parallel kinematic machine tools with minimal effort

New innovative machine tool concepts like parallel kinematics require the development process to be continuously supported by simulation. Otherwise it will be impossible to exploit their full potential due to the complexity of the kinematic and dynamic behavior. Nevertheless, machine tool manufacturers often refrain from employing simulation tools because of the high effort and expenses expected for the introduction of this technology. It is against this backdrop that the paper presents a method to support the development process of parallel kinematic machine tools with a minimum of effort. An analysis of the development process identifies the machine characteristics that have to be determined for each stage. A simulation method is developed based on these results and on the requirements for a seamless integration of the simulation techniques into the different stages of the process. It is implemented and tested by the example of a parallel kinematic machine tool that has already been successfully introduced in industry.

Virtual Optimization of Machine Tools and Production Processes

Faster development of innovative machine tools, shorter processing times, improved surface quality of workpieces, higher machine productivity – these are just a few of the wishes and demands of machine manufacturers and end-users. Time-to-market is decisive; in some industries, six months too late on the market can already be decisive in losing the race for market leadership. The key to success lies in virtual techniques. These are an extremely cost-effective way to increase productivity in all phases of the machine tools life cycle. Siemens AG, the leading provider for control and drive technology, sees itself as a partner for the whole machine tool industry and offers four phases of simulation support which cover the entire life cycle of a machine: Mechatronic Support for simulation for machine development, Machine Simulator for supporting commissioning, Virtual Production for the optimization of production and, finally, Virtual NC Kernel (VNCK) for the testing of NC part programs at the end-user.

The post-1990 rebirth of the US machine tool industry: a temporary recovery?

After several decades of decline, the US machine tool (MT) industry entered a modest period of recovery in the mid-1990s. With the slowdown of the global economy in the early 2000s, however, this recovery has stalled. By now, there are clear signs that rates of firm exit are increasing. This paper compares the results of a survey of MT producers (conducted in 2000) with more recent industry data (2004). Four years after the optimistic findings of the 2000 survey were reported, we find that many of the small-to-medium sized producers have either ceased operations or have downscaled substantially. While virtually every US manufacturer of MT products has been negatively affected by the global economic downswing, adverse business conditions have had a disproportionately severe impact upon firms that cater primarily to local markets. MT manufacturers located within the nation's traditional industrial heartland have been the hardest hit, notably as a result of rising import competition. In contrast to locally-oriented producers, our findings suggest that a small number of innovative MT companies have been faring quite well as a result of continued export development. The paper concludes with a brief discussion of several futures for the domestic MT sector.

Advances in micro ultrasonic assisted lapping of microstructures in hard–brittle materials: a brief review and outlook

Micro ultrasonic assisted lapping was first proposed as an effective micromachining technique for hard–brittle materials by Masuzawa's group. Through applying innovative machine tool design concepts, holes as small as 5 μm in diameter and aspect ratios larger than five were machined in quartz glass and silicon. Further applications of the micro ultrasonic assisted lapping to generating microstructures in hard–brittle materials were extended by Brinksmeier's group, and path-controlled micro ultrasonic assisted lapping was implemented in LFM, University of Bremen. These excellent results have demonstrated a promising potential for practical, but the knowledge of micro ultrasonic assisted lapping is far from sufficient to provide a complete understanding and instructive rules for industrial users. The paper briefly reviews some new advances in micro ultrasonic assisted lapping, and then introduces some necessary research topics involved in the process in order to put it into practical microfabrication.