Simulation of the process of cutting gears of cycloidal drives with disc mills by the radial-circular continuous forming method
Students Name: Brukhal Pavlo Romanovych
Qualification Level: magister
Speciality: Mechanical Engineering Technologies
Institute: Institute of Mechanical Engineering and Transport
Mode of Study: full
Academic Year: 2022-2023 н.р.
Language of Defence: ukrainian
Abstract: Relevance of research. Progressive developments in industries are based on new technologies, which ensure an increase in the functional characteristics of machines and equipment. Drives used in machine-building products, which consist of gears and are determined by energy consumption, load capacity, accuracy of rotational movement transmission, which do not meet modern requirements. To ensure the appropriate operating parameters of machines, equipment, mechanisms, reducers using cycloid gears, in particular spur gears, can be used. Helical gears belong to planetary gears with off-center. Drives with spur gears are characterized by small dimensions and weight, high efficiency, long service life, low inertia, high speed, high load capacity due to multi-pair engagement, smooth operation, reliability, compactness. The design feature of planetary spur gears makes their application one of the most effective and promising in the drives of production machines, machine tools, robots, and control devices. The functional indicators of spur gears and gears depend on the accuracy indicators obtained during tooth cutting operations. Gear wheels are cut by two methods - copying and running-in. The application of each individual method depends on many factors, such as the dimensions of the wheels, the annual production program, the availability of appropriate equipment and the financial capabilities of the enterprise. The copying method is implemented using disk or modular enddiscrete rotation of the gear blank by one angular step. The copying method belongs to the low-productivity and one that does not provide high accuracy according to the norms of kinematic accuracy. The running-in method is implemented with the help of worm cutters on tooth milling machines with continuous rotation of the wheel blank and the worm cutter. The method is productive and ensures the necessary accuracy of the cut gears. Gear cutting methods are used to cut gears with an involute tooth profile. There are standardized tools for this. There are no standardized gear cutting tools for cutting gears with a cycloidal tooth profile, so gear cutting operations require special tools that belong to high-cost gear cutting tools. For efficient cutting of gears with a cycloidal profile of teeth, it is advisable to use the method of radial-circular forming of teeth with disc cutters installed with eccentricity during continuous coordinated rotation of the disc cutter and the cut gear wheel on a gear milling machine. However, for the process of cutting gear wheels with a cycloidal profile, there is no information about setting up a technological system in which the method of radial-circular formation of the profile of the teeth is implemented. Therefore, it is relevant for mechanical engineering to establish technological parameters by modeling the process of radial-circular forming with a disk cutter installed witheccentricity on a gear milling machine, teeth of a cycloidal profile of spur gear wheels. The purpose of the research is to model the process of formation of cycloid profile teeth in the cylindrical wheels of spur planetary off-center gears during continuous radial-circular movement of disk cutters. The object of the study is the process of radial and circular continuous forming by a disk cutter of the outer toothed crown of the cylindrical wheel of the spur planetary gear. The subject of the study is the technological characteristics of the process of profiling the gears of the spur planetary transmission Research tasks. 1. Analysis of the functional characteristics of planetary spur gears and technological possibilities of methods of cutting gears of cycloidal profile. 2. Development of models of formation of the profile of the spur gear wheel. 3. Modeling of the profiling of the external teeth of a cylindrical gear wheel by a disk cutter during continuous radial and circular movement. 4. Study of the influence of the technological parameters of the process of radial-circular cutting of teeth with a disk cutter on the quality characteristics of the cycloidal profile of the gear wheel of the spur gear. Scientific results. 1.1. Mathematical models of the formation of the profile of the teeth of the cycloidal profile of the gear wheel for the spur planetary transmission have been developed. 2. Developed mathematical models of continuous shaping of the side surfaces of teeth of a cycloidal profile on cylindrical gears by a disk cutter installed with an eccentricity on the tool mandrel of a gear milling machine. 3. The formation of the right and left profile of the teeth of the wheel is carried out by two points of the disk cutter, installed with an eccentricity on the mandrel of the gear milling machine, which are placed at the minimum distance from the axis of rotation of the processed gear wheel. 4. The shape of the profile of the cut teeth depends on the eccentricity, the radius of the middle circle, the length of the main cutting edge of the disk cutter and the number of cut teeth. The technological factors that have the greatest influence on the profile of the teeth are the eccentricity of the installation of the disk cutter and the width of the working edge of the tooth of the disk cutter. 5. The eccentricity of the installation of the disk cutter and the length of the main cutting edge of the disk cutter belong to the main technological factors, the calculated selection of which ensures the proper accuracy of the profile, which is estimated by the value of the tolerance of the profile of the corresponding cylindrical wheels with the involute profile of the teeth of the appropriate accuracy. 6. The outer radius of the disk cutter does not affect the formation of the profile of the gear wheel by the method of radial - circular forming. Practical value. 1. It is proposed to use the method of radial-circular shaping with a disduring continuous rotation of the workpiece, for cutting the teeth of external cylindrical wheels used in spur gears. 2. A technique for selecting technological parameters for setting up gear milling machines for cutting cycloidal profile gear wheels for spur gears has been developed. 3. It is proposed to use the spur gear model as a digital analogue to determine the eccentricity of the disk cutter when compared with the expected cycloidal profile of the wheel teeth obtained by the disk cutter by the radial-circular forming method. 4. It is suggested that the selection of technological parameters be carried out using parametric modeling of the formation of the cycloidal profile of the wheel teeth. 5. The use of the method of radial-circular forming withspur gear wheels will allow to increase technical and economic indicators in the manufacture of spur drives. Key words: disk milling cutter, spur planetary gear, cycloidal profile, radialcircular movement, technological parameters of tooth cutting, tooth milling.