1. Automatic measuring instrument 2. Quasi-stop switch 3. Workpiece (left and right crank) 4. Headstock top 5. Dial 6. Grinding wheel dressing seat 7. Grinding wheel dressing position 8. Grinding wheel origin position 9. Axial positioner 10. Grinding wheel Working position 11. Tailstock tip 12. Auxiliary bracket 13. Automatic gauge connector 14. Gauge base mount layout example design Gauge Wheel For Planters,New Rubber Tire Gauge Wheel,Corn Planter Gauge Wheel Tire,Spoke Gauge Wheel Seeder Wheel Hebei Huichao Machinery Parts CO., Ltd. , https://www.huichaoagparts.com
Designing CNC Special Grinding Machine with New Ideas
1 Introduction CNC machine tools are the combination of high-precision machine tool manufacturing, microelectronic technology and computer technology. With the introduction of foreign high-end CNC machine tool products and the introduction of foreign CNC technology, China's CNC machine tool manufacturing has developed rapidly. With the breakthrough in the study of machine tool structure, the emergence of a large number of mature functional components, and the continuous improvement of production efficiency and function, CNC grinders are guided by market demand, and special grinders are used as the guide to complete the gradual completion of programmable controllers (PLC). The mechatronics products are developing toward the direction of numerical control products. It has become a new trend to carry out the design, manufacture and application of special CNC grinding machines. 2 New Design Ideas The traditional design philosophy is to plan the design and layout of the overall layout according to the functions that a single machine tool should have: Principle design, mechanism design, and part design for each component: Formulation of process plan: Design and manufacture of fixtures: Machine tools Trial production. A new product or special machine product development cycle is more than one year. With the emergence of functional modular design concepts, typical platform (bed) components, spindle components, feed components, control components, (hydraulic, pneumatic, mechanical) drive components, support positioning components, detection components independent, machine tools The design changes from a single machine design to a serialized machine design. The development of a series of products, only the program design, overall layout design, the use of typical components, plus a small number of parts design, without trial production, can become a new product or commodity. On the premise of ensuring the manufacturing cycle, the design cycle can be greatly reduced. The further development of modularization, the socialization and standardization of a large number of typical components, and the emergence of a variety of functional components have enabled us to design the machine tool only under the condition of selecting functional components. As a machine tool manufacturer, the key is to design a well-adapted machine tool platform, that is, to be able to install various purchasable functional components, adapt to various processing functions, have good protection functions, and can become a work of art. This is the design idea of ​​simplification, standardization, elementalization, and modular convergence. According to this product design idea, products that can provide the market should be diversified to meet the needs of various users. In the near future, products will be designed specifically for each user's requirements, and identical products will no longer exist. According to user requirements, the production of special-purpose CNC machine tools has become the mainstream. Specialization means reducing redundant functions and reducing product costs. CNC special grinders are designed based on this new idea. 3 The mature craftsmanship of the user is a guarantee of successful design. As a machine tool designer, he is often in the position of the manufacturer and pays attention to the realization of the function design of the machine tool. What problems arise in the use or use of the machine tool cannot be fully given in the design process. consider. This design method can often not be successful at one time, and may even be the outcome of failure. Therefore, modern designers must pay more attention to the experience of the machine tool application and application process. CNC special grinders are clearly targeted at design time. The targeted basis is the user's experience accumulated in the processing technology of the workpiece or the experience and inspiration of the new process for special machine tools from abroad. At the time of development, we went to the user factory for research and practice. Understand the workpiece loading and unloading, support (support of the center frame of long shaft or special-shaped shaft parts), clamping, positioning, grinding parameters (including: coarse grinding, fine grinding allowance, speed, grinding time), grinding Cutting sequence, precision, roughness, efficiency, selection of automatic measurement function, grinding wheel material and parameters, grinding wheel dressing parameters, frequency, coolant supply pressure and type, working temperature suitability, according to the operator's habits, adjust the fixture Positioning method, machine tool suitability, machining accuracy and manufacturability. Users who use existing general-purpose grinding machines are proposed to replace them with CNC machines, which will require higher requirements in terms of machining efficiency, machining accuracy, reliability, and safety. At this time, new configurations must be carried out based on the existing mature technologies and their feasibility should be analyzed. It can be commercialized once it is designed and manufactured, and it is really used on the production line. 4 Universal Grinding Machine Both the CNC special grinding machine and the universal grinding machine must perform the same grinding function. In the cylindrical grinding, it should have the function of supporting and driving the workpiece to rotate and reciprocate: it should have the function of high-speed rotation of the grinding wheel and can realize the feed displacement. This is the basic function for completing cylindrical grinding and is a necessary condition for product existence. These functions are designed into the workpiece headstock module (including transmission, spindle system, positioning, drive, etc.), tailstock module, table module (including drive, positioning, etc.), wheel frame module (including transmission, spindle system, positioning, protection , drive, feed, etc.), grinding center (can achieve cylindrical, inner circle, face, end surface cylindrical grinder) turntable module and wheel dressing module. These modules are set on a bed platform, plus some control systems and auxiliary function modules, to develop a universal grinding machine. The features of these modules are: Independent function-independent modules, easy to group and collaborate on modules with independent independence such as electrical, digital display, detection, hydraulic and cooling systems, to form a variety of variants, and achieve different processing accuracy. Different machine functions with different degrees of automation and different machining efficiencies. The basic parts functionalized basic parts refer to large parts of machine tools, such as bed, workbench, box and sliding seat. Most of them use castings or welding parts, and the rough preparation and long processing period will affect the rapid development of products. Therefore, the entire series of modular design generally only uses the same type of large parts as the basis, the functionalization, so that the machine tool can expand the working space, adapt to different machine appearance layout, modeling and protection: so that the machine's specifications, performance in ensuring the rigidity of the premise There is a possibility of change. A grinder bed module can be used for fixing various cabinets and slides, and can be used to derive universal type, end circular type, high-efficiency cut-in type or other special-purpose machine tools. Adapt to the application of new technologies The application of new technologies at present is mainly aimed at improving the efficiency (higher speed), improving the processing accuracy (nanometer level), the degree of automation (digital control), flexibility, and networking. As long as a certain space is added in the base module or in the box and the slider module, some modules can be added. The socialization of functional components under the guidance of the modular idea, such as the independence, standardization and professionalism of various functional components such as drive systems, control systems, spindle systems, guide rails, ball screws, cooling systems, refrigeration systems, and inspection systems, etc. Manufacturing promotes the development of the modular design method. A large number of functional modules of the CNC special grinder come from the factory's own general-purpose grinder module and the social supporting functional components that can be purchased. 5 Main design points The special grinding machine for the design of the work table is based on some typical parts (such as crankshaft, camshaft, gas valve, left and right crank, eccentric shaft, universal joint, gear shaft, etc.) for high-efficiency grinding. Therefore, during the design, the grinding process analysis is performed on the platform (workbench) of the general-purpose grinding machine selected for the workpiece, and the corresponding dedicated section is set. These include: Automatic loading and unloading of workpieces with smaller workpiece loading and unloading. Larger workpieces are manually loaded on the auxiliary trays, and the workpieces are sent out by flipping robots and manually unloaded. The support of the workpiece includes the auxiliary brackets before the positioning of the workpiece and the positioning of the workpiece head, the tailstock top support, or the headstock chuck support. The corresponding auxiliary functions are configured, such as injecting the top hole with lubricating coolant, to prevent the positioning and thermal deformation of the support. The driving and quasi-stop of the workpiece is driven by the headstock spindle dial or mounted on a rotatable spindle chuck to drive the workpiece to rotate. For some externally shaped workpieces (crankshaft, camshaft, etc.), when the drive is stopped, it should stop at a good loading and unloading position, and the drive device should have a quasi-stop function. Workpiece installation and identification According to the characteristics of the workpiece, the axial and radial positioning of the auxiliary bracket is designed and controlled by photoelectric or non-contact signals to prevent errors during human installation. Axial positioning of the workpiece is based on a shoulder surface of the workpiece as an axial positioning reference. Through the axial axis of the workpiece feed, the positioning gauge is contacted with the workpiece positioning shoulder surface to obtain the base point of the CNC axis programming. For some workpieces with its own shoulder surface to complete the axial positioning during installation, positioning gauges may not be provided to simplify the grinding process. However, the accuracy of the positioning shoulder surface processing of the previous process must be improved accordingly. Automatic measurement of the workpiece For the micron-level grinding accuracy, the online automatic measuring device of the workpiece is generally configured. Most of the automatic measurements are installed on the tabletop, and through programmed control, the workpieces are measured, and coarse, fine, and size signals are issued and the workpiece is ejected. Grinding and cooling of workpieces mostly use high pressure, large flow, magnetic, paper filtration, and even cooling systems with refrigeration devices. Grinding wheel relative to the origin of the workpiece grinding wheel is different from the car, milling, drilling tools, it is easy to loss, the size of the ever-changing. As the size of the grinding wheel becomes smaller, the position of the wheel holder continues to move forward. When designing, it is necessary to consider the extreme position of the wheel frame movement, the possible spatial position of interference, and the position where the wheel dressing may be performed. For some machine tools that can achieve end face and cylindrical grinding at a time, the grinding wheel is inclined at an angle of 30° with respect to the workpiece. The amount of movement in the feed direction of the grinding wheel frame has a functional relationship with the amount of movement in the vertical direction. Therefore, it is required that the numerical control system has an oblique axis function. Set the dressing wheel Dressing wheel dressing device is mostly set on the work surface or on the head frame to make full use of the movement of the two feed CNC axes to realize the molding and dressing of the grinding wheel outer circle. In this way, the machine structure is greatly simplified. The appearance of the thin diamond wheel dressing device can greatly improve the grinding wheel dressing accuracy.