The ceramic-bridge machines are constructed from the same component parts as the standard ALTERA C range, but are optimised during build at the company's Derbyshire production facility to deliver 16 percent higher accuracy during a measuring cycle, with 13 percent better repeatability and 50 percent more accurate scanning. Volumetric accuracy is from 1.3+L/350, repeatability from 0.0013 mm and scanning accuracy from 0.002 mm.
When implementing design improvements to the ALTERA C HA, particular attention was paid to upgrading the moving bridge. The spread of the air bearings supporting the main drive leg has been widened to increase the stiffness of the bridge assembly by 17 percent overall, which is particularly beneficial during high-speed movements. Advantages to the user are considerable, as measuring uncertainty when chasing tolerances down to microns is significantly better.
For the same reason, the bearing mountings have been further stiffened and their alignment improved. Due to the increased dynamic forces in play when measuring on the fly, the new design is especially helpful when using a scanning probe.
The pre-loaded, wrap-around air bearing configuration runs with a reduced air film thickness for low energy consumption and gives repeatable measurement results, even at fast axis speeds. Friction drives provide smooth motion together with exact positioning at continuously varying speeds, as well as zero backlash and overload protection.
Multi-sensor capability is provided, with the Renishaw PH10M motorised probe head able to deploy a touch-trigger probe, scanning probe or laser scanner. LK's proprietary, DMIS-based, multi-sensor CAMIO software enables programming and measurement based on 3D CAD data as well as comprehensive reporting.
The five sizes of ALTERA C HA have a measuring envelope above the granite table ranging from nominally 700 x 650 x 500 mm for the smallest CMM up to 1,500 x 850 x 650 mm for the largest. The machines are compact for the size of their respective measuring volumes and are also fast, accelerating at up to 1,390 mm/s/s for high inspection efficiency.
They are equally at home in an inspection department or on the shop floor, especially as pneumatic anti-vibration mounts can be specified to isolate the CMM from nearby sources of low-frequency vibration, such as large machinery. Maintenance costs are low and all models carry an unrivalled 10-year accuracy guarantee covering dimensional stability.
New on show also at MACH 2024 will be LK's own CMM laser scanning probe, SLK25 VIVID, and the TSR-5 tool change and storage rack, both of which are affordable solutions, as well as automation with a collaborative robot, and a second-generation LK FREEDOM arm with L100 VIVID laser scanner.
Additionally there will be a standard ALTERA C CMM, the latest version of LK's CAMIO programming, analysis and reporting software, including the popular module for automated inspection of gears, and the LK FREEDOM rotary index table that speeds inspection of parts using an articulated arm, raising metrology productivity. Industry-leading third-party hardware and software will also be in evidence on the stand.
