Search

The purpose of the paper is to design an extruder to ensure continuous flow of material and retraction of the melted material into the extruder of the printers operating with pellets ABS, PLA or other materials used. The way in which 3D printers work differs from that of plastic injection machines by the fact that for the execution of a piece it is necessary for the extruder to position itself at different points of the surface without depositing the material. If it does not stop the flow of material during the repositioning move, then the executed piece will be compromised. Designed pieces were designed with the help of the Inventor Software and it was determined experimentally whether the extruder is working. It was found that the original design did not fully meet the requirements of the coat-coat process, which is why rethinking of the extruder's operation and modifications to ensure retraction of the material is necessary. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to design the mechanism for lowering and lifting the car platform using CAD software (Inventor). The used mechanism to drive the car platform is the quadrilateral mechanism due to the low cost of its compared to a gear train. Operating a mechanism can be done manually by applying a force on frame attached on the crank or by operating through a small winch. Kinematic analysis was performed using the software mentioned above. Lowering the platform to ground level is necessary in some cases to be loaded heavy objects onto the platform when are not available forklifts and other lifting mechanisms. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to make the geometric model to the Archimedean spiral, curve often used in practice. Although it is a widely used, in AutoCAD there is no command with which to represent the Archimedean spiral. The method used for determining the mathematical relationships that define the spiral is the coordinate transformation, and for the calculation of the points which define it, is use AutoLISP, representation being made in AutoCAD. The result of this work is to develop an AutoLISP program which can represent the Archimedean spiral, presented a method that can be applied to the representation of any curves used in the technique. [ABSTRACT FROM AUTHOR]

The purpose of this work is to demonstrate that by milling the archimedian cylindrical worm on CNC machines using frontal-cylindrical milling tools are obtained roughness higher than those obtained by classical methods of turning. Now worms produced from improving steel are finishing through turning and worms produced from case-hardening steel are finish through grinding. Surface roughness obtained by turning is comprised in the range between 3.2 -6.3 μm and the surface roughness obtained by milling is in the range 1.6-3.2 μm. The worm producers are interested in increasing the possibilities of processing the worms on the CNC machines with specific tools with productivity and as well as higher accuracy. The experiment which form the basis of the work has been done on CNC machine, OKUMA MULTUS B300 by processing a batch of archimedian worms with ma = 10, z1 = 2 with the use of a mills FRANKE, code 2887A.010. The paper demonstrates that surface roughness obtained by milling through the use of a frontal- cylindrical milling tool from carbide mono-block is comparable to that obtained by grinding. [ABSTRACT FROM AUTHOR]

Nowadays in our society modern science uses a wide range of materials to perform multiple functions. One of the fields in which biological, synthetic and hybrid materials have found various applications is related to the medical one. The variety of materials used in medicine adapts to specific requirements and applications, due to the wide range of physical, chemical and biological properties that these materials can guarantee. The present review paper offers a short review, based on the data available in the scientific literature, on the possibility of using materials for dental application. [ABSTRACT FROM AUTHOR]