Westec 2001: Renishaw unveils optical machine tool probing system
Renishaw Inc. brings CMM levels of probing performance and 10-fold probe life to industry's largest machine tools with its MP700E High-Power Optical System. The MP700E combines the sub-micron repeatability of the company's MP700, industry's most accurate machine tool probe, with 12-meter (39.3 ft) transmission range and 360° signal coverage from any spindle orientation. The high-power MP700E system allows operators of very large, 5-axis machine tools — such as aerospace gantry profilers — to verify critical features in process, achieve tighter tolerances for more precise fits, and even perform final inspection while the part is still on the machine tool.
The extended-range MP700E system uses a high power infrared transmitter, modified optical receiver and machine interface with high-speed digital switch, while retaining the engineering breakthroughs of the MP700 probe.
Strain gage trigger design minimizes pre-travel variation and its effects on probing precision to provide CMM-like precision — unidirectional repeatability of 0.000010 in. (0.25 µm) with a 2-in. (50 mm) stylus. Solid-state construction increases probe life ten-fold, while strain gauge sensors deliver low trigger force and a uniform 3-dimensional triggering pattern. This allows faster probing on complex parts while eliminating the programmer's requirement to compensate for lobing characteristics that can affect probing precision.
A multi-channel digital filter recognizes and ignores unintended triggers resulting from machine vibration and high acceleration/deceleration forces. This makes the MP700E particularly suited to high-speed and high-power machining centers, such as those used in the aerospace and off-road equipment industries.
The high-power system is designed for applications requiring extended range transmission up to 12 meters, environments which are not conducive to the use of RF transmission, or tilt-spindle applications which position the probe at complex vectors that traditionally result in loss of an optical signal.
CNC probing can make it viable to do final inspection and "buy off" of finished parts by the machine tool to reduce in-process time. This eliminates the delays, difficulties, and costs in transporting and fixturing large parts for post-process inspection. In-process probing provides a form of closed-loop process control that can enable machining centers to achieve accuracies comparable to boring mills and other high-precision machines for time- and cost-saving process consolidation.
Renishaw Inc., 5277 Trillium Boulevard, Hoffman Estates, IL 60192 USA. Tel: 847-843-3666. Fax: 847-843-1744.
Source: Renishaw