Numerical control lathe main composition and characteristics of mechanical structure
Numerical control lathe mechanical structure of main components and characteristics of release time: 2015 - 06 - 24 clicks: a 3092 times, numerical control lathe machine structure of the main mechanical structure of the nc machine tools, in addition to the machine components, consists of the following parts: 1, the main drive system; 2, feed system; 3, implementation artifacts turning, positioning of 臵 and accessories; 4, some parts and auxiliary function of the system and install 臵 such as hydraulic, pneumatic, lubrication; Cooling system and chip removal, such as protective 臵; 5, rest or automatic tool change outfit 臵 ( ATC) ; 6, automatic pallet loading 臵 exchange ( APC) ; 7, special function 臵 such as loading 臵 tool breakage monitoring, precision testing and monitoring, such as: 8, loading to complete automatic control function of the feedback signal 臵 and components. CNC machine tools based or say big, usually is refers to the lathe bed, base, column, beam, slide, workbench, etc. It is the foundation of the whole machine tools and frameworks. Other machine parts, components, or fixed on the basic pieces, or work on its rail movement. Other mechanical structure according to the function of the machine tool needs to choose. Such as the general nc machine tools in addition to the basic parts, and the main transmission system, feed system and hydraulic, lubrication, cooling and other auxiliary 臵, this is the basic structure of nc machine tool machine structure. Machining center shall also have the ATC, at least some double location APC, etc. Flexible manufacturing cell ( 融合) In addition to the ATC with location more APC, some even have used for loading industrial robots. Nc machine tools according to the degree of automation, reliability requirement and function of special needs, choose all kinds of tool breakage monitoring, precision machine tool and workpiece detection, compensation 臵 and accessories, etc. Some special machining nc machine tools, such as machining CNC machine and laser cutting machine, the spindle components is different from general CNC metal cutting machine tool, but need to use the servo motor drive machine moving parts to realize feed movement, is the commonness of all kinds of CNC machine tools. Second, the numerical control machine tool of the mechanical structure characteristic, high rigidity and high vibration 1) The basic concept of stiffness of machine tool rigidity of machine tool is one of the technical characteristics of the machine tool, it reflects the machine tool structure deformation resistance. According to the properties of machine tool by load, machine tool under the action of static force is referred to as the static stiffness of machine tool stiffness; By the stiffness of machine tool under the action of dynamic force called the dynamic stiffness of machine tool. To meet CNC high speed, high precision, high productivity, high reliability and high degree of automation, compared with general machine tools, CNC machine tools should have higher static stiffness, dynamic stiffness, vibration resistance. Some regulations of the state, the stiffness coefficient of nc machine tools is higher than ordinary machine tools at least more than 50%. The basic theory of ordinary machine tool stiffness also applies to the numerical control machine tools. And the stress and deformation analysis, dynamic stiffness and dynamic characteristics analysis, in order to improve the static stiffness and dynamic stiffness of machine tool measures adopted by the principles also apply to the same kind of CNC machine tools. 2) Improve the nc machine tool structure stiffness of commonly used measures, 1) Improve the static stiffness and natural frequency of machine tool components. Commonly used methods are reasonable cloth 臵 stiffened plate structure; Set 臵 loading unloading 臵 to balance load in order to compensate the zero, the static deformation of parts; Improve the contact stiffness between the components or component and foundation stiffness of coupling place. ( 2) Improve the machine tool structure damping characteristics. Within the common way to have a big cavity filling core and damping materials such as concrete, using relative friction in vibration to vibration energy dissipation; In the large surface using damping coating; Make full use of the joint surface between the friction damping; Using new materials and steel plate welded structure, etc. Should be stressed that the numerical control machine tool of the high rigidity and vibration resistance is relative to the ordinary machine tool, not the higher the stiffness and vibration resistance is better. 2, reduce the influence of machine tool thermal deformation thermal characteristics of nc lathe is one of the important factors that affect the machining accuracy. Because of nc machine tool spindle speed, feed rate is far higher than that of ordinary machine tool, and cutting parameter of the workpiece and machine tool parts produced by hot cutting heat conduction effects than ordinary machine tool, and the influence of thermal deformation of machining accuracy is often difficult to correction by the operators. Therefore, to reduce the effects of CNC machine tool thermal deformation measures should be paid special attention to. 3, the structure of the mechanical transmission system greatly simplified nc machine tool spindle drive system and feed drive system with ac and dc spindle motor and servo motor drive, the two types of motor speed range is big, and can stepless speed regulation, so that the spindle box, feeding transmission and transmission system greatly simplified, enclosure structure is simple, gears, bearings and shaft parts quantity greatly reduce even without gear, directly driven by motor spindle or feed ball screw. 4, high transmission efficiency and zero clearance 臵 and element numerical control machine tool under the high feed speed, work to be smoothly; And has a high positioning accuracy. Therefore, the feed system of mechanical transmission 臵 and components requires high life, high rigidity, no clearance, the characteristics of high sensitivity and low friction resistance.