Measure Delicate Medical Materials with Accuracy, Not Force

Heidenhain Corporation (Schaumburg, IL) offers their Zero-Force Metro Length Gauge with uncompromising accuracy to measure extremely sensitive materials without fear of product deformation. It is especially suitable for measuring malleable materials in medical devices. Two new variants of the established 1Vpp Metro gauge are available immediately in 12 mm stroke lengths; one with gauging forces of 0.25 N in any mounting orientation with a weak spring and one with a gauging force of ~0.0 N mounted vertically downward with a Zero-Force spring mechanism. Even with the improvement to the force spec, the Metro still maintains its high accuracy of ±0.2 µm and thermal stability due to the optical encoder technology inside.

In related medical part manufacturing, Heidenhain offers the RSF Elektronik MSR 40 modular rotary position feedback system to machine designers who want a quick way to measure angle on larger rotary axes and auxiliary axes in machine tool and metrology for medical part manufacturing. The MSR 40 optical kit style encoder provides a 200 micron grating pitch on a steel tape that has three ways of being applied to the axis of motion. This is ideally suited for machines that require motion feedback for a full 360 deg or a segment thereof. The MSR 40 is available with a minimum diameter of 150 mm to a maximum of 1,150 mm, with larger diameter versions available upon request. The same reader head can be used for all the various diameters offered and is available with analog 1 Volt peak-to-peak interface as well as digital TTL interface with up to one hundred times interpolation.

All measuring tape versions of this encoder have a ±30 micron per meter accuracy associated with the circumference of tape. The MOR version tape requires a small pocket to be milled from the axis in order to accommodate a clamping mechanism which ensures accuracy over the joint of the measuring tape ends. The MER version has small plastic tubes on the back of the measuring tape as a supporting structure and the measuring tape can be screwed together to complete a full 360 deg measurement. This version is very quickly mounted to the axis as a benefit because of the tube backed measuring tape and is rated for a lower dynamic performance and rigidity as a consequence of very simple mounting. The MKS version of tape is a segment with an adhesive and is pre bent to the diameter to ensure long lasting quality of measurement.

For increased metrology data collection in medical manufacturing, RSF Elektronik also offers the UFC 430 3-axis input device that allows the connection of up to three encoder feedback components into a module that acts as a data collection device with latching capabilities that is suited for motion applications. With a power supply range of 8-16 Volts, this 3-axis input device can accept either TTL or 1 Volt peak-to-peak interfaces. Each 1 Volt peak-to-peak interface encoder can be further interpolated up to 400 times by the UFC 430. The module has three counter channels with 32 bits each, one load and two latch registers for each channel and has an event counter with an integrated timer for pulse width, frequency and speed measurements.

An Input/Output interface exists for cascading more devices and asynchronous latching for special assignments. Asynchronous latching of the counter values for each encoder channel by software, reference mark of the encoder, or external hardware signal are all possibilities. The unit comes with a CD of demo programs, driver software, and operating instructions.

Heidenhain Corporation, 333 East State Parkway, Schaumburg, IL 60173, 847-519-4213, www.heidenhain.us.