Papers by Keyword: Helical Groove

Abstract: Face teeth grinding of special tools, as hobing worm milling cutters are, is the shape and cinematically complex operation with the respect to achieving the necessary accuracy and resultant shape geometry. The grinding wheel shape, it ́s size and the control helix angle of hobing worm are the primary factors which are compelling the ground groove accuracy during the face teeth sharpening process. Inappropriately selected combination of these parameters causes undercut of this surface and the negative impact on required accuracy. The main aim of the solution is to find a variable and to create a parametric mathematical model to calculate appropriate grinding wheel shape according to the input factors – hobing worm and grinding wheel parameters which affects this issue. This system will be used to create the initial grinding wheel surface and a helix groove undercut calculation program. The graphical part of this programme will be the next benefit.

Abstract: This paper presents a general mathematical model for NC-machining an APT-LIKE rotating cutter. The design model of cutting-edge and helical groove are also developed by using the principles of differential geometry and kinematics. The analytical solution for the resolution profile of helical groove has also been developed. The results of numerical experiment indicate that the proposed systematic design method by using 2-axis NC machine setup are feasible and reliable.

Abstract: This paper presents the mathematical model of helical groove of the end mill according to the differential geometry and meshing principle based on the grinding wheel attitude. The profile of the helical groove can be precisely calculated using a given wheel attitude and the relative motion between the workpiece and the grinding wheel.The relation between the grinding wheel attitude and the rake angle can be obtained through adjusting the grinding wheel attitude angle.And the accurate 3D model of helical groove was generated in the SolidWorks.The research shows that the grinding wheel attitude is the main factor that affects the rake angle of end mill.There is a linear relationship between the rake angle and the grinding wheel attitude. The smooth and accurate 3D model of helical groove lay the foundation for studying the cutting performance and dynamic characteristics of end mill.

Abstract: A purely analytical method, based on the meshing theory, is presented to establish the exact helical groove and circumferential cutting edge model of end mills, for the solution of its low design precision and efficiency problems. Firstly, a coordinate system to represent the relative space position relations between grinding wheels and end mills is built and the mathematical model of the helical groove is precisely calculated with a given wheel profile and relative movements between the wheel and the workpiece. Then, the rake angle, inner radius and wheel positions of machining the clearance faces is computed. Finally, a 3D model of the end mill is generated by using OpenGL.

Abstract: In the process of milling special helicoid , there is a cusp point between its profile curve and linear esicoaginal junction . Ordinary milling cutter can't processing .If milling tool profiles are calculated and designed by smooth connection, the findings of milling tool profiles will appear profiles jagged or profiles detached phenomena. For separation of milling cutter blade shape, in order to prevent point was cut off, it can be treated with the method of open groove, but the two point easy to wear and affect the durability of the cutting tool. Solving method of transitional profiles of detached section is given.

Abstract: The paper presents results of the tests concerning slide bearings having modified journal with helical groove. Such a bearing is more wear-resistant than the classical bearing in case of hard particles presence in oil. Investigations show that above mentioned modification results in over twofold decrease in wear intensity in case of suitable helical groove parameters. Differences in worn journals surface topography for investigated variants have also been stated.

Abstract: In order to describe the forming grinding principle of screw rotor, the mathematical model of screw rotor’s helical groove and forming grinding wheel are established by differential geometry theory and numerical analysis method. And the contact line equation is derived. To optimize the traditional method of calculating forming grinding wheel by known rotor end section profile, a numerical analysis method (Accumulated Chord Length Parameter Method) has been presented in detail. This method can improve the efficiency and reliability of the calculation of forming grinding wheel axial profile. Taking the asymmetry linear screw rotor (female) as an example, this paper calculates the grinding wheel axial profile and draws it using special designed software. The simulation examples are done by CAD (Computer Aided Design) based on the secondary development technology of UG. This study provides a precise 3D model which can be used in areas such as finite element analysis and virtual testing experiments.

Abstract: The paper presents results of tests concerning slide bearing with helical groove on the journal selected properties. It has been stated that during lubrication with contaminated oil helical groove results in wear decrease. On the other hand while lubricating agent was clean oil helical groove results in load carrying capacity decrease and oil flow rate increase. The proposition of non-dimensional index describing the groove and helical line is also presented in the paper. This index is correlated with bearing characteristics and its wear

Abstract: Upon studying the form grinding principle of helical groove and the conjugate movement between the grinding wheel and screw rotor, the equation of their contact line is firstly derived. The problem of smoothing the profile of grinding wheel is then solved by using the point selection smoothing method which is concludes from the theory of complex curves and numerical analysis. Finally, with the help of computer, the simulation processing is done with the final result shows that this design method is reliable. It can not only reduce the time for design and the number of trial samples but also provides a 3D model which can be used in virtual test of screw rotor.