High-speed CNC machining originated in the early 1990s. It mainly uses spindles for high-speed spindles and high-linear linear speeds with linear motors. It is mainly used in the mass production of the car industry. The aim is to replace the multi-spindle with a single spindle machining center with high spindle speed and high-speed linear feed motion, but it is difficult to achieve a high spindle speed and high-speed feed combination machine, so that in high-volume production, a high degree of flexibility is beneficial to the product. Quickly update without sacrificing productivity. In actual production, some well-known automobile factories, such as Shanghai General Motors Corporation of China, have already replaced the combination machine tools with a production line consisting of high-speed machining centers. The current trend is to continue to expand its range of applications. In order to reduce costs, some companies do not use linear motors, but use hollow-pass coolant, larger diameter and larger lead ball screws. Toshiba machines in Japan use double-ball screws with hollow coolant to enhance transmission rigidity. However, no matter what kind of ball screw is used, the maximum moving speed is generally not more than 50m/min, and the acceleration is up to 0.5g~1g. However, HüLLERHILLE's nbh110 high-speed machining center adopts the "frame-and-frame" structure. Make the moving parts smaller in quality. Therefore, despite the use of the ball screw, the linear velocity of the X, Y and Z axes can still be as high as 75 m/min with an acceleration of 1 g.

Another area of ​​high-speed machining applications is the high-speed milling or turning of hardened steel with cubic boron nitride tools, which is very beneficial to the mold industry. In order to pursue the final high precision, it is generally desirable to perform finishing after the mold is hardened. In the past, the only available processing method for hardened molds was electrical machining. Electrical discharge ablation is micro-chip processing with extremely low efficiency. The efficiency of high-speed milling hardened steel can be several tens of times higher, making it an ideal replacement for electrical machining. Although high-speed milling such as deep and narrow grooves, small curvature radius arc surfaces and clear angles on large molds cannot be used, high-speed milling can be used for rough and semi-finishing, and electric machining is used for final machining. Greatly shorten the mold processing cycle. For a large number of shaped and narrow and deep grooved molds, only electrical machining methods can still be used. For this reason, electrical processing will never be completely replaced.

The challenge of high-speed milling of hardened steel to electrical machining has prompted electric machining machines to move toward "high speed". Japan's Sodick Company in 1999 (developed in 1996) is the first in the world to introduce a wire-discharging machine that replaces a ball screw with a linear motor. On the IMTS2000, Sodick's EDM and punching machines are all equipped with linear motors. A linear motor with a linear motion speed of about 36 m/min and a resolution of 1 μm replaces a linear speed of only about 1.3 m/min, and a ball screw with a resolution of 1 μm. The superiority of the transmission cannot be directly reflected in the high speed. This is determined by the servo nature of the EDM machine that continuously maintains the discharge gap and does not short circuit. It behaves as an instantaneous advance, an instantaneous stop, or even a momentary retreat. Since the linear motor greatly improves the transmission forward and has a linear thrust of up to 3000N, it is possible to generate an instantaneous high addition (decrease) speed, form a high-frequency instantaneous intermittent impact, and wash away the iron filings generated by the electric erosion. This eliminates all "Flushing" devices while maintaining a minimum and consistent spark gap for fast feed. Therefore, not only can the efficiency be greatly improved (generally 40%), the accuracy can be improved, the surface roughness can be improved, and the problem of "scouring" cannot be solved in the past (such as it is difficult to drill "smear" on tiny and dense electrodes. Holes, etc.) cannot be electrically processed.

The aerospace and aerospace industries are traditional applications for high speed machining. The reason is that the main materials are aluminum and aluminum alloy; the second is that the parts often have extremely thin walls and ribs, and the rigidity is very poor. These ribs and walls can only be machined by cutting forces at high speeds. The latest trend is: Recently, these industries have used large-scale aluminum alloy blanks to make large parts, such as wings and fuselage, to replace multiple parts to avoid numerous rivets, screws and other coupling methods. This not only saves expensive assembly man-hours and tooling, but also increases the strength, rigidity and reliability of the components. Thus, at this IMTS2000, CINCINNATI and the Italian company Jobs exhibited large-scale high-speed milling machines (models HyperMach and JoMach159) for the aircraft industry. This type of machine has the following characteristics:

(1) Further increase of spindle speed and power: Since the aircraft industry uses the overall blank "hollow" method to machine parts, the amount of cutting is extremely large. Therefore, the space in which the spindle speed and power can be increased is also large. According to CINCINNATI, in the aircraft industry, spindle speeds of 15,000 r/min and 22 kW were high speeds. With advances in technology, advanced machine tools have increased to 40,000 r/min and 40 kW. And their HyperMach has been increased to 60,000r/min and 80kW, which is a new height.

(2) Extra long X stroke and gantry movement: Since the "wing" type is a slender part, the JoMach machine has an X-axis stroke of up to 30 m and a Y-axis of only 2 m. It is said to be used to process the wings of the European next-generation fighter "Typhoon". The HyperMach machine has a maximum X stroke of 46m and a Y axis of only 2m. The double-sided total length of the Aluminax series of Marwin's UK machine tools is 100m. Such a long X-stroke can only be moved by the gantry (often multiple gantry) and not by the workbench.

(3) The use of linear motors for high-speed linear transmission: Unlike the previous helical gear racks or worm gears for large-scale machine tools in the aerospace industry, such high-speed milling machines also use linear motors. This is to meet the needs of the spindle's ultra-high speed, extra power and long X stroke. After using a linear motor, the HyperMach machine has a feed rate of up to 60m/min, a fast speed of 100m/min and an acceleration of 2g. According to CICINNATI, they had tried cutting a thin-walled aircraft part on HyperMach and it took only 30 minutes. The same part takes 3 hours to process on a typical high-speed milling machine and 8 hours on a normal CNC bed. This fully demonstrates the power of ultra-high speed machines.

Another high-speed large-scale milling machine, LinX, introduced by the company in 2000 for the aviation and mold industry, is a bridge layout with linear motors. The maximum feed rate is 60m/min, the acceleration is 0.6g, and the spindle speed is 24000r/min. The power is 44kW. Thanks to the high-speed spindle and high-speed feed, the machining time can be reduced by 50%, the machine structure is simplified, and the parts are reduced by 25%, making it easy to maintain.

The above description of linear motor applications has expanded from the initial automotive industry to the processing of electrical machining tools, the aerospace industry and large molds.

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