Nakamura JX-250 Offers Large Machining Area Envelope
Unit allows maximum part length and performing left and right simultaneous machining
Methods Machine Tools’ Nakamura-Tome JX-250 turn-mill offers a large machining area envelope for precision milling and turning of complex parts. It also has a twin lower turret configuration, which allows flexibility for complex component manufacturing. According to the company, the unit features an NT smart cube milling spindle, which is one of the shortest on the market. This 12,000-rpm spindle permits maximum part length on the left and right spindles, including when the horizontal tool spindle and lower turrets are in the cut. To optimize part transfer, independent right spindle guideways on lower turrets minimize the distance between the spindles at 11.8" (300 mm). For high processing flexibility, a single or twin lower turret design is offered with overlapping travels and Y-axis box guideways are standard. The machine provides up to 168 tool stations and can perform left and right simultaneous machining.
The company says the machine provides high accuracy and exceptional rigidity due to its horizontal bed design with a wide, low center of gravity and vertical column structure, weighing 55,000 lbs. The NT Thermo Navigator AI technology controls thermal growth during machining and compensates for temperature changes. The multitasking turning center has a maximum turning diameter of 12.6" (320 mm) and maximum turning length of 65" (1,650 mm). The left and right spindles have 3" (80 mm) and 2.5" (65 mm) bar capacity, respectively. Milling spindle X, Y, Z travel is 25.4" × ± 4.9" × ± 32.5" (645 mm × ±125 mm × ±825 mm) and its B-axis positioning range is 240°. The machine features a Fanuc 31i-B5 CNC and SmartX PC-based 19" high-resolution color touchscreen. A 5-axis precision milling software package is included.
The JX-250 also has an NT Work Navigator that can recognize the coordinates of machine parts with non-round shapes such as those in forgings and castings. This feature eliminates the need for costly positioning fixtures and clamping devices. An advanced NT nurse system all-in-one software package is also included to provide convenient, easy-to-use support for the operation, programming and production. Critical functionality includes phase recognition (key for multitasking), direct chucking to enable transfer without positioning error, and precise synchronization of the left- and right-hand spindles. Additional functions include a load monitor for identifying tool wear/ breakage, tool life management and machine monitoring. All Nakamura-Tome machines are equipped with a standard electronic detector safety feature that greatly reduces the impact and force of a machine collision. Should a crash occur, within 4 milliseconds after the crash, servo motor-feeding direction is reversed and the machine will stop in EMG mode.
Advanced mill-turn machines with bar fed material handling can overcome several inherent weaknesses of production machining on vertical machining centers.
Vertical turning centers that use the main spindle to load and unload themselves are finding increasing acceptance as multitasking capabilities make them efficient processing centers for producing chucked parts.
Introduced to the turn-mill machine tool design in about 1996, the Y axis was first used on a single-spindle, mill-turn lathe with a subspindle. The idea of a Y axis on a CNC originated from the quality limitation of polar interpolation and the difficulty in programming, not from electronic advances in controls or servomotor technology as one might commonly think.