Quality of turning using multiedge heads with elastic guiedes and elctromagnetic drives

Запропоновано експериментальну установку, що складається з багаторізцевої головки адаптивного типу з пружними напрямними для тонкого точіння, в якій керування положення різців у процесі обробки відбувається через електромагнітний двонаправлений привод різцетримачів з мікроконтролерним інтелектуальним керуванням. Експериментально доведено ефективність вирівнювання зусиль різання з допомогою розробленої установки на основі алгоритмів керування, що передбачають стабілізацію як рівнодійної осьових складових сил, так і сумарних переміщень різальних елементів.The paper deals with experimental facilities including adaptive type multi edge head with elastic guides for fine turning. The adjustment of the head cutting edges positions in the process of machining is performed by two- directional electromagnetic drives with micro controller based on intellectual control. The algorithm and software control program to solve the problem of automated accuracy supply of the parts machining technological processes are given. It is established that the proposed head operation makes possible to provide high level response to momentary changes of cutting force components at cutting edges as well as cutting forces stabilization. It is also possible to control the feed change of each cutting tool and to obtain the vibration less high precession cutting process of fine turning. The experimental research was carried out to prove the efficiency of cutting forces equalization, when using the constructed facilities on the base of control algorithms, that cover either the resultant axial forces maintenance or summarized displacement of cutting edges. The conducted analysis allows to conclude that using of multi edge head with cutting forces equalization mechanism influences on the efficient increasing of the technological machining system rigidity. This in its turn makes possible to decrease the influence of cutting forces components on the part manufacturing accuracy. The parameters of the machined work pieces roughness as well as the geometric shape accuracy were investigated using profilometer-profilograph of 296 model and roundness measuring machine BE-20A. As a result this research testified the multi edge head working efficiency and adequate correspondence of experimental and theoretical investigations (the error is from 10 to 30%). It makes possible to decrease the chip-cutting time and non-productive machine time and to increase of the machining productivity while providing the necessary machined surface quality

Feed and power characteristics in the process of fine turning using multiedge cutting heads

Запропоновано конструкції багаторізцевих головок адаптивного типу з пружними напрямними для тонкого точіння, в яких керування положення різця в процесі обробки відбувається через електромагнітний двонаправлений привод різцетримачів з мікроконтролерним інтелектуальним керуванням та гідроциліндрами. Доведено ефективність вирівнювання зусиль різання з допомогою розроблених головок на основі алгоритмів керування, що передбачають стабілізацію як рівнодійної осьових складових сил, так і сумарних переміщень різальних елементів.The paper deals with the feed and power characteristics in the process of fine turning using multiage heads. The modern problems of fine turning as well as the problems of machining accuracy and continuous chip breakage are analyzed and search directions of manufacturing and constructive design solutions are defined. In addition to machining technology and tools improvement the conceptually new mechatronic heads are developed on the base of precession mechanics, electronics, electro engineering techniques integration with particularly regard to the multi edge machining of adaptive type. Constructive design combination of operational and driving units of cutting machines linear and rotational motion mechanisms that realize the direct-action drive conception allows improving the accuracy, response speed and reducing capacity losses. The presence of automatic control system and manufacturing process control sensing elements incorporated in the given design makes the head intellectual and autonomous that allows creating advanced designs of metal cutting machine units. The designs of fine turning multi edge heads of adaptive type with elastic guides are considered. The turning tool position control in the process of machining is performed by the bidirectional electromagnetic drive of tool holders with intellectual control system based on microcontrollers. As a result the proposed control system gives the possibility to response quickly to the material extraneous impurities while machining as well as redistribute cutting forces in the process of cutting edges wear in the multi edge tools. The information data recording to the independent memory is also available with the following computer analyzing. Two control algorithms for operation of proposed multi edge fine turning cutting heads with elastic guides are proposed. In this way the multi edge turning process control is performed by electronic devices in a form of the programmed CNC system. The input signals of the tool position are submitted to the above system in which they are operated using the necessary algorithm. The signals to control the cutting edges drives are gone out of the CNC system. The dynamical position of the cutting tools is fixed by the feedback sensors communication system. The output signals are sent to the regulatory inconsistencies system to correct the input signals. To prove the mentioned above algorithms operation the determination of feed and forces characteristics are developed. These characteristics deals with two conditions of the work piece multi edge turning: in a case of eccentricity work piece machining and in case of machining of the work piece with a radial run out. Three edge cutting heads designs with elastic guides and electromagnetic and hydro drives are developed to equalize the axial as well as radial components of cutting forces. The effectiveness of equalizing of cutting forces using the developed multi edge heads on the base of control algorithms is proved. These algorithms provide stabilization of summarized axial components of cutting forces as well as summarized cutting elements displacements