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The paper is primarily focused on the determination of the ultimate strength of pressed materials in the form of steel sheets. The breaking strength of homogeneous materials such as e.g. steel sheet is not a relevant indication for pressed steel sheet waste material. The ultimate strength serves as a main parameter in the design of sheet metal cutting machines. For the design and technological design of machines and equipment for shearing steel waste in the form of pressed sheets, it is necessary to know the limit strength of the material. The paper describes in detail the experimental procedure and the principle of determining the ultimate strength of the steel waste sheet. Several dozen experimental samples of pressed metal waste were used. The very principle of the experiment consisted of sheared samples, while monitoring the shear force and the thickness of the pressed material. The ultimate strength of the shear material was calculated from the measured data. The measured and calculated data were statistically processed to increase the objectivity of the determination of the already mentioned ultimate strength parameter of the pressed waste sheets.

The aim of the research work was focused on a research of manipulators design using suction grippers. The results of the research can be applied in the design of jigs - manipulators for handling thin sheets. The FME analysis was used in the investigation to show the course of elastic deformations and stresses in stressed areas. An experimental observation of the change in the free deflection of the workpiece from the positioning of the suction cups under gravity load by means of a laser 3D scanner was carried out for the FEM deflection detection method.

The aim of the paper is to analyze the application possibilities of the Vortec tube in relation to its energy and economic aspects.The first part consists of an introduction, a description of the energy separation phenomenon in the Vortec tube and the application possibilities and parameters affecting Vortec tube functioning.The second part of the paper deals with the energy balance and economic operational aspects of Vortec tubes produced commercially. The energy balance consists of a thermal calculation of the Vortec tube, the energy-efficiency identification of thermal energy production and a comparison with thermal equipment used in practice. The thesis next continues with an economic analysis of the Vortec tube’s operation, connected with the production of compressed gas. The output of this part is a cost assessment of thermal energy production by means of the Vortec tube and its economic classification in the thermal resources generally used in Slovakia.The last part of the paper includes a static thermal calculation of a dryer using hot air produced by the Vortec tube from the point of view its thermal and temperature potential.

The contribution deals with the trimming of beef cattle hooves by means of a new method, specifically with a liquid water jet. Present methods of trimming hooves are outdated; almost nowhere are new modern technologies used for this purpose. The use of more contemporary methods would enable a reduction in the high labour demands to accomplish this task. But the main advantage of this new method is increasing so-called animal WELFARE. Present-day methods which are performed mechanically are always stressful, and many times also painful, for the animal. In the article we will specifically focus on the possibility of trimming the hooves of beef cattle by means of a water jet. The original research was focused on the size of the basic parameters such as pressure, flow, nozzle diameter and cutting time. The results of this initial research serve as a step towards further research, whose goal will be the design and testing of complex equipment for trimming beef cattle hooves by cutting with a liquid water jet.

An article is about mechanical effect of the physic-mechanical material properties on the radial pressure in the compression chamber during the compacting process of wood. Some general methods that describe the transformation process of axial pressure into the radial pressure are shown, As well as the mathematical or experimental methods specifying dependencies and physical conditions. Mathematical finite element method in this area is very useful, but rarely used. Common problems using FEM are the proper definition of the physical material properties in a particular stage of compaction. Material properties are greatly influenced by a number of factors such as moisture, fraction size, chemical composition, current temperature, radial macro structure, axial macrostructure, current pressure and others. The chamber material and the manufacturing processes or the state of wear has an impact on the physical conditions. In terms of tensile elastic deformations, these complex effects reflect and can be merged into several properties. The conversion of axial to radial pressure indicates that some properties of the compacted material have a major impact on the process, such as friction between material and chamber, elastic modulus and Poisson's ratio. The geometry of the pressing chamber also has a significant impact. This paper does not deal so much with the pressing chamber geometry but more so with the characteristics embodied in experimentally measurable quantities. The measurement of these properties in combination with the application of FEM methods proves to be a highly progressive method for understanding the compaction process and the engineering design of compaction machines for the production of briquettes and pellets. The article urges further examination and measurement of a wider range of material properties in the densification process.

The quality of cutting machines is affected by several factors that can be directly or indirectly influenced by manufacturers, technicians and users of machine tools. The most critical qualitative evaluation parameters of machine tools include accuracy and stability. Investigations of accuracy and repeatable positioning accuracy were essential for the research presented in this paper. The aim was to develop and experimentally verify the design of a methodology for cutting centers aimed at achieving the desired working precision. Before working on the topic described here, it was necessary to make several scientific analyses, which are summarized in this paper. We can build on the initial working hypothesis that by improving the technological parameters (e.g. by increasing the working speed of the machine, or by improving the precision of the positioning) the quality of the cutting machine will also be improved. For the purposes of our study, several investigated parameters were set affecting positioning accuracy, such as rigidity, positioning speed, etc. First, the stiffness of the portal structure of the cutting machine was analyzed. FEM analysis was used to investigate several alternative structures of the cutting machine, and also an innovative solution for beam mounting. The second step was to integrate two types of drives into the design of the cutting machine. The first drive is a classic rack and pinion drive for cutting machines. To increase (improve) the working speed of the machine, linear motors were designed as an alternative drive. The portal of the cutting machine was designed for a working speed of 260mmin−1 and acceleration of 25 m. s−2. The third step was based on the results of the analysis. In collaboration with Microstep, an experimental cutting machine in a portal version was produced using linear synchronous motors driving the portal on both sides, and with direct linear metering of its position. In the fourth step, an experiment was designed and conducted to explore the positioning accuracy and the repeatable positioning accuracy.

This paper presents the theoretical design for experimental verification of the structural and technological parameters of the Parallel Kinematic Structure. The experimental equipment was developed at the Faculty of Mechanical Engineering, STU in Bratislava. It is called Tricept, and due to its kinematics it is classified as a parallel structure. The previous phase of the project dealt with developing a mathematical model of the tool path. We have worked with two methods, a Monte Carlo method and the use of a mathematical analytical geometry structure. The calculated values were verified by comparing the results of the two methods. Based on the equations that were obtained, we can design the control of the tool path during cutting. The next stage focuses on the test methods and on verifying the structural and technological parameters of Tricept. The experiment is designed on the basis of the EN ISO 9283 standard, and involves testing the technological parameters: one-way positioning accuracy and repeatability of the position, changes of multidirectional positioning accuracy, repeatability and accuracy of the distance, position overshoot, drift of the position parameters, path accuracy, and repeatability of the path. This paper classifies the measurement methods and presents the measurement processes and the equipment for the experiment.

The article is focused on the test methods and verification of structural and technological parameters of the parallel kinematic structure - the tricept. The experiment is designed based on the standard EN ISO 9283 and involves testing of technological parameters: one-way positioning accuracy and repeatability of the position, changes of multidirectional positioning accuracy, repeatability and accuracy of the distance, position overshoot, drift of position parameters, path accuracy and repeatability of the path. This paper presents the designed experiment classifying methods of measurement and measuring processes and equipment.