(1) Present situation, level and development trend at home and abroad
Since 1980s, due to the introduction of CNC system, DC feed servo motor, spindle motor and its servo unit from FANUC in Japan and Siemens in Germany, the reliability of CNC system has been greatly improved, but the reliability of the whole machine is not high enough. With the technical progress and perfection of the machining center, domestic manufacturers have noticed that some parts of products are replaced by standard functional parts, and at the same time, they have given priority to the brand-name products of world-famous companies (such as CNC system, rolling linear guide, ball screw, bearing, ATC device, hydraulic pneumatic components, electrical components, testing components, etc.) as supporting equipment, which has improved the grade and reliability of domestic machining centers to a certain extent and shortened the gap with similar products abroad. At present, the reliability of domestic machining centers is still not high compared with similar products abroad. In addition, there are some defects such as protective seal, rough appearance and unsatisfactory overall shape, which affect the market competitiveness of domestic machining centers to some extent. With the sustained development of the national economy and the strong support of the state for domestic CNC machine tools, there is an increasing demand for gantry machining centers and CNC gantry boring and milling machines in many important industries in China. Therefore, many domestic manufacturers who have never been involved in manufacturing gantry boring and milling machines have gone into battle one after another, and developed various gantry machining centers and CNC gantry boring and milling machines through technology introduction and cooperative production to meet the needs of users.
(2) The purpose and significance of project research and development.
With the increase of the specifications of gantry machining center, the vibration generated during machining also increases, which affects the rigidity and motion stability of the fuselage and limits the development speed of large gantry machining center. At present, the main specifications on the market range from 800-5000mm to 2000-28000mm. It should be pointed out that in domestic gantry machining centers and CNC gantry boring and milling machines, about 90% of the specifications are concentrated in the size section of 1000-2000 mm, and almost 95% of the varieties are mobile with fixed beams. In contrast, the workbench width is more than 3 meters, especially the large gantry machining center with moving beams and the CNC gantry boring and milling machine with a width of 4000-5000 mm, which has great technical difficulty and high technical content. In order to solve the above problems, our company has developed a large CNC gantry machining center, which will promote the technical progress of domestic machining centers and improve the quality level of equipment manufacturing. The purpose of this project is to research and design the basic platform of large gantry machining center series. On this platform, the basic machine tools of gantry machining center series, the special options carried by customers and the future hardware development and update conditions can all achieve performance parameters superior to national standards and respond to market demand quickly.
(3) The technical level and market prospect of the project.
The large-scale CNC gantry machining center series machine tools developed in this project refer to the models with the transverse stroke of 3 meters, 4 meters, 5 meters and 6 meters on the X axis and the longitudinal stroke of 2.7 meters on the Y axis. With the rapid development of aviation, airplanes, automobiles, wind power generation and yachts, the requirements for equipment specifications and sizes are getting higher and higher. This project is specially developed to meet the increasing demand of all walks of life. This model has reasonable overall layout, beautiful appearance and convenient operation. Three-axis full stroke design strengthens the rigidity of the fuselage and effectively avoids the vibration generated during processing; It has a wide range of industries, a large social demand and a good market prospect.
The large-scale CNC gantry machining center technology of this project can greatly improve the rigidity and motion stability in the machining process. It is a product urgently needed by the market and has a huge market prospect. The implementation of this technology will greatly improve the sales volume and sales profit of related products of the company.
Second, the research and development content and objectives
(1) Main contents and key technologies of the project
The large-scale CNC gantry machining center developed in this project adopts three-axis full-stroke design, and the three-axis adopts linear roller slide rails, in which the X-axis adopts 15 slider three-line guide rail design, the Y-axis guide rail layout adopts vertical and horizontal combination, and the Z-axis adopts square ram full box structure and four slide rails, so as to strengthen the rigidity of the fuselage, effectively avoid the vibration generated during machining, and greatly improve the rigidity and motion stability during machining. The X axis adopts imported precision planetary gear reducer, and the headstock moves up and down by oil pressure and nitrogen belt counterweight. Linear guide rail has the characteristics of zero intermittence, and is used for arc cutting, bevel cutting and so on. And the surface texture of the processing effect is relatively uniform. The linear guide rail replaces the traditional sliding technology with rolling, which has the characteristics of small friction resistance and sensitive directional movement. The high rigidity of the wire rail makes it wear less and has long service life, which is suitable for the processing environment of high-speed feed system.
In the large-scale CNC gantry machining center of this project, two stepped mounting pieces are respectively arranged at the upper and lower ends of the front end of the stepped beam, and the upper mounting piece retracts inward relative to the lower mounting piece. When installing the machine tool head, the machine tool spindle can be as close as possible to the main column, thus effectively improving the accuracy, durability and stability of the machine tool. Moreover, under the condition of not increasing the thickness of the casting in front of the beam, the beam can be ensured to have enough rigidity, so that the gantry machine tool can not only meet the requirements of heavy-load cutting, but also be used for precision machining.
technical innovation
1, the three-axis adopts linear roller slide rail, which has the characteristics of high rigidity, low noise and low wear, can move quickly and obtain the best looper accuracy, among which the x-axis adopts three-line rail and 15 slider; The arrangement of Y-axis track adopts vertical and horizontal combination, which greatly improves the stability of slideway movement. Z axis adopts square ram full box structure and four slide rails, which greatly improves the rigidity and motion stability during machining.
2. The X-axis adopts imported precision planetary gear reducer to replace the traditional direct drive or belt drive, which improves the output torque of the motor and ensures the movement accuracy of the worktable.
3. The headstock uses oil pressure and nitrogen to move the counterweight up and down, which improves the stability of the counterweight and the flexibility of quick response.
(three) the main technical indicators or economic indicators
X-axis stroke: 3200/4200/5200/6200mm, Y-axis stroke: 3200mm, Z-axis stroke: 1000mm.
Worktable size: 3000 (4000/5000/6000) × 2500mm.
Spindle motor power: 22kw
Spindle speed: 6000 rpm
Three-axis motor power X/Y/Z:9/7/6kw.
Cutting speed: 6m/min
Fast feed speed: 12m/min.
Numerical control system: FANUC 18I
Third, research and development methods and technical routes
The large-scale CNC gantry machining center of this project includes spindle, column, walking beam, slide seat and machine head. The stepped beam is arranged on the upright post, and the sliding seat can move horizontally relative to the stepped beam. The machine head is installed on the slide seat and can move vertically relative to the slide seat. The upper and lower ends of the front part of the stepped beam are respectively provided with two stepped mounting parts, the mounting part at the upper end contracts inward relative to the mounting part at the lower end, and the sliding seat passes through the two mounting parts. The front part of the stepped beam includes a vertical part whose upper end is connected with the installation part and an inclined part whose lower end is connected between the vertical part and the installation part. The upper and lower ends of the front face of the stepped beam are respectively provided with two stepped mounting parts, and the mounting part at the upper end contracts inward relative to the mounting part at the lower end, so that the spindle of the machine tool is as close to the main column as possible when mounting the head of the machine tool, thus effectively improving the accuracy, durability and stability of the machine tool. Moreover, under the condition of not increasing the thickness of the casting in front of the beam, the beam can be ensured to have enough rigidity, so that the gantry machine tool can not only meet the requirements of heavy-load cutting, but also be used for precision machining.
The large-scale CNC gantry machining center of this project adopts three-axis full-stroke design, and the three-axis adopts linear roller slide rail, which has the characteristics of high rigidity, low noise and low wear, can move quickly and obtain the best loop accuracy, among which the X-axis adopts three-wire rail 15 slider design; The arrangement of Y-axis track adopts vertical and horizontal combination, which greatly improves the stability of slideway movement. Z axis adopts square ram full box structure and four slide rails, which greatly improves the rigidity and motion stability during machining. The X-axis adopts imported precision planetary gear reducer to replace the traditional direct drive or belt drive, which improves the output torque of the motor and ensures the movement accuracy of the worktable. The headstock uses oil pressure and nitrogen to move the counterweight up and down, which improves the stability and quick response flexibility of the counterweight.
In the lubricating oil circuit system, pressure switch detectors are installed in the oil circuits at the front and back ends of the filter. When only one pressure switch detector is abnormal, that is, the output pressure or holding pressure does not reach the set value, the controller will automatically give an alarm and block the downlink instruction to protect the modem from running under insufficient lubrication. In addition, the controller can compare the pressure values measured by two pressure switch detectors, and judge whether there is oil blockage through the comparison results, which is convenient for timely elimination and avoids the phenomenon of poor lubrication.
Fourth, the existing research and development foundation
Introduce the establishment of the company, main products, R&D department and R&D achievements.
Verb (abbreviation of verb) List of personnel of R&D project team
Project leader:
R&D personnel:
Six, plan the work schedule
The preliminary structural design of the product was carried out in June of 1, 20 1 year x/month-201year x.
2. The core structure of the product was studied from July 2065438 to October 2065438/kloc-0.
3. Conduct product testing and structural modification from February, 20 1X to August, 201X..
4. The final product test was conducted from September of 20 1X to September of 20 1x, and 165438+ 10.
May 201year 65438+February, the remaining problems of products were solved and the project research and development was completed.