Multitasking With A Small Footprint
The Integrex i-150 shows how a multitasking machine for small precision parts can combine done-in-one process with a compact structure to reduce floor space requirements. Most multitasking machines for parts of this size use a second spindle for endworking of parts after cutoff. This machine uses a swing-away workholding device instead.
A new multitasking machine from Mazak Corp. (Florence, Kentucky) addresses one of the drawbacks that some shops find with this ever-more-popular type of machine tool. Many of these machines require a large amount of floor space even though the workpieces are relatively small. Shops with limited space may have difficulty accommodating these seemingly oversized machines on the shop floor. The Integrex i-150 Multi-Tasking Center, however, has a small footprint. The base of the machine sits within a 58-square-foot area.
Clearly, machine tool platforms that combine milling and turning capability are a boon for shops looking for a reliable means to complete a part in one setup. Essentially, one such machine does the work of two. Because many designs for multitasking machines include a second spindle, their space requirements are proportionately larger. The i-150, which provides done-in-one processing of small, complex workpieces, does without this second spindle. According to the builder, it is ideal for medical appliances and high-precision component machining that involves round, square or angular features. The machine can accommodate bar stock as large as 2.56 inches in diameter.
It uses a swing-away workholding device instead of a second spindle, thus making structural provisions for this spindle unnecessary. A typical scenario for done-in-one processing on the i-150 starts with the workpiece automatically feeding into the main, 15-hp horizontal spindle. When operations on the front side of the workpiece are completed, the workholding device swings up to clamp it, as shown in Figure 1. After cutoff, the device swings down 45 or 90 degrees with the workpiece in its grip. Repositioning the 10-hp, 12,000-rpm milling spindle in the B axis enables machining on the back face of the workpiece (Figure 2). The workholding device does not turn the workpiece, but circular interpolation of the milling head provides a substitute. Y-axis travel extends ±3.94 inches (±100 mm) from the center line to provide the milling spindle with the range and flexibility for this function. When the workpiece is unloaded, the workholding device swings out of the way to clear the machining zone. The device can also act as an NC tailstock in its upright position.
Another way this machine saves space is by providing a front-loading tool magazine. This puts tools close to the ATC and eliminates the need for side or rear access to the magazine. The machine comes standard with a 36-tool magazine. The large number of tools makes it possible to run many part types in short batches or in a sequential series, to produce a ready-to-assemble kit without restocking the magazine. A 72-tool version is also available.
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