Modern CNC lathes and tooling permit high cutting speeds and feeds, leading to increased machine efficiency and productivity. To ensure operator safety, however, European Norm EN 1550 states that the gripping force of chucks should be checked regularly.
To this end, Kitagawa has introduced the KGFM series of wireless grip force meters, designed to measure holding force quickly and accurately. It can perform either a static test, or a dynamic test with the spindle running, in which case the instrument records the rpm of the chuck as well the force it applies to the billet or casting.
The Japanese-made sensor is available from UK agent, 1st Machine Tool Accessories, in two standard sizes with measuring diameters of 72 mm and 125 mm respectively. By installing rest pads in the appropriate locations, both types can be used on 2- and 3-jaw chucks, while the larger model can also take measurements on 4-jaw chucks.
In addition to ensuring safety by avoiding the risk of a workpiece flying out of the chuck, the units maximise lathe productivity by ensuring that full gripping force is being applied, allowing high rotational speeds and feed rates to be programmed into machining cycles. Repeatability of component production is also improved.
The dynamic grip force meter, which uses a standard 9 volt battery, comes as a kit including wireless force sensor, rpm magnetic wand, standard rest pads, display and padded carrying case. Stop rings are available for controlling insertion depth, as are custom sensors for measuring the gripping force and rpm of larger chucks.
