Hybrid technological equipment: on the issue of a rational choice of objects of modernization when carrying out work related to retrofitting a standard machine tool system with an additional concentrated energy source

OBRABOTKAMETALLOV Vol. 23 No. 3 2021 MATERIAL SCIENCE EQUIPMENT. INSTRUMENTS 5 2 3 the systems under consideration, given in [75–85], were used to study the proposed structural composition and configuration of HMS, in which surface heat treatment and mechanical operations are integrated. When developing integral metal-cutting equipment, it is planned to implement the method of highenergy heating by high-frequency currents on one of the technological transitions of a hybrid machine. The generating lines of the surface being treated are formed by local heating areas. The dimensions of these lines are contingent on the design features of the inductors for the HEH HFC and are determined by the width of the active wire of the inductor and the length of the ferrite magnetic core (Fig. 2). It is obvious that the operations of surface hardening and shaping by milling (Fig. 3) require the same coordinated relative movements of the workpiece and the cutting tool. The results of the structural-kinematic analysis showed that at all transitions of complex machining (preliminary milling, HEH HFC hardening and finishing milling), the executive movements and the set of parameters configured in it are identical. a b Fig. 3. Generation of geometry (flat surface): a – during machining (milling); b – during surface hardening by HEH HFC with loop inductor with a magnetic core Figure 4 shows particular structural kinematic formulas in conjunction with structural-kinematic diagrams (SKD) for each processing method individually. The subsequent synthesis of the generalized kinematic structure of the developed hybrid metal-cutting system based on a bracket-milling machine was carried out according to the scheme of the machine modular layout (Fig. 5). With this method, the structural kinematic formula can be represented as follows:  1 2 0 ( ), v XYZ b w w + Ñ where X, Y – longitudinal and transverse movement of the cross table; Z – vertical movement of the console; b – rotation of the spindle head; w1 – manual movement of the spindle sleeve along the spindle axis; v Ñ – rotation of the spindle with the cutting tool; w2 – manual movement of the inductor along the spindle axis. The Cv block that performs the primary motion in milling is additionally marked with a ∧. Currently, most of the parameter-oriented (dimension) series of general-purpose machine tools are built according to the law of geometric progression with a constant denominator φ equal to 1.26 or 1.41. The range of sizes of workpieces or cutting tools used for each member of the ranges, as a rule, significantly exceeds this value. Therefore, there is some overlap in the size ranges D of equipment for adjacent members of the parameter-oriented series. It provides certain flexibility in the machine tool holding of machinebuilding enterprise, which allows it quickly and practically without a decrease in productivity switch to the production of new products without equipment replacing. However, multiple duplication of individual size ranges on machines of the same series leads to an increase in the number of its members and, as a result, to an increase in the cost of designing, manufacturing and operating equipment. Therefore, the problem of establishing the optimal structure of parameter-oriented series of technological equipment is very relevant.

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