Heidenhain: Absolute Sealed Linear Encoder with small cross section (LC485 Series ID: 689681-xx)

The sealed linear encoders feature an aluminum housing that protects the scale, scanning carriage, and guideway from chips, dust, and splash water. Elastic sealing lips enclose the housing from below. The scanning carriage moves along the scale with low-friction guidance. A coupling, which connects the scanning carriage to the mounting base, compensates for misalignment between the measuring standard and machine slide.

Linear encoders from HEIDENHAIN for numerically controlled machine tools can be used nearly everywhere. They are ideal for machines and other equipment whose feed axes are in a closed loop, such as milling machines, machining centers, boring mills, lathes, and grinding machines. The beneficial dynamic behavior of linear encoders, their high permissible traversing speed, and their acceleration in the direction of measurement predestine them for use on highly-dynamic conventional axes as well as on direct drives.

HEIDENHAIN also supplies linear encoders for other applications, such as:

• Manual machine tools

• Presses and bending machines

• Automation and production equipment

Advantages of linear encoders: If a linear encoder is used for measurement of the slide position, the position control loop includes the complete feed mechanics. This is referred to as Closed Loop operation. Transfer errors from the mechanics can be detected by the linear encoder on the feed axis, and corrected by the control electronics. This makes it possible to eliminate a number of potential error sources:

• Positioning error due to heat generation in the recirculating ball screw

• Reversal error

• Kinematic error through the ball-screw pitch error

Linear encoders are therefore indispensable for machine tools on which high positioning accuracy and a high machining rate are essential.

Mechanical design: Linear encoders for numerically controlled machine tools are sealed measuring devices: an aluminum housing protects the scale, the scanning carriage, and its guide from chips, dust, and splashing water. Downward-oriented elastic lips seal the housing.

The scanning carriage travels along the scale on a low-friction guide. A coupling connects the scanning carriage with the mounting block and compensates the misalignment between the scale and the machine slide.

Depending on the encoder model, lateral and axial offsets of ±0.2 mm to ±0.3 mm between the scale and mounting block are permissible.

• 689681-01 ML=70mm,
• 689681-03 ML=170mm,
• 689681-04 ML=220mm,
• 689681-05 ML=270mm,
• 689681-09 ML=470mm,
• 689681-11 ML=570mm,
• 689681-18 ML=920mm,
• 689681-19 ML=1020mm
• 689681-55 ML=1840mm

• 558362-03