Heidenhain MT 1281 Metro Length Gauges provide 1Vpp output and ±0.2um accuracy. The MT 1281 plunger actuation is extended by gravity with a 12mm travel length.
Metro length gauges are designed with ball-bush guides. The following are some of the basic properties of ball-bush guides in HEIDENHAIN length gauges: Low friction, which makes versions of length gauges with reduced gauging force possible. Safe plunger extension and retraction even with high radial force. High precision of the measuring loop thanks to a guide that is free of play (the bearing and plunger are specially fitted during manufacture).
The Heidenhain MT 1281 Metro Length Gauge come with a built in spring that extends the plunger to the measuring position and produces the gauging force. While at rest the plunger is extended. The gauging force depends on the following criteria:
· Operating orientation
· Plunger position (the force changes over the course of the measuring range)
· The direction of measurement (whether extension or retraction of the plunger is used)
External plunger actuation via gravity: MT 1281 plunger is freely movable. There is an optional coupling with a moving machine element for position measurements. The force needed to move the plunger specified ad required moving force.
Operating orientation: MT 1281
· Upward: -0.13 N
· Downward: +0.13 N
The MT 1281 length gauges feature a standard clamping shank with 8h6 diameter. Therefore these Heidenhain length gauges can be easily used with existing measuring fixtures and stands. Heidenhain offers a special clamping sleeve and clamping bush with one screw each. These accessories will make it easier to fasten the length gauge without overloading the 8h6 clamping shank of damaging the ball-bush guide. The clamping bush also enables a wide tolerance field for the tightening torque and improves fastening. Sleeve: ID 386811-01/Bush: ID 1177968-02
Thermal dynamics: Heidenhain length gauges have a defined thermal behavior. Since temperatures can vary during the measurement process and possibly cause a measuring loop, Heidenhain uses special low coefficient of expansion material for the components of the measuring loop.
Repeatability: Whereas the system accuracy applies over the entire measuring range, for some applications the reliability is the decisive factor. It plays an important role in repeated measurements. The repeatability of the length gauges is usually better than the values listed by Heidenhain. Reliability depends on the combination of materials used in the components, installed electronics, optomechanics used, and the bearing of the plunger. MT1281: 0.03um
