Sensors for High Speed Cutting

As an innovative supplier of sensors for machine tool manufacturer, we have established ourselves as a market leader in the machine tool industry over the last few decades.

MiniCoders are designed for integration in spindle motors and provide contact-free operation. They are equipped with a magnetic measuring system that, together with a target wheel as a measuring scale, facilitates incremental acquisition of rotary movements. This solution is extremely compact and saves space.

Due to the compact size of the MiniCoders, and the fact that the target wheels can be flexibly dimensioned, they are suitable

• for integration in C-axles
• for the acquisition of speed and position in the case of milling, grinding and turning equipment
• for auxiliary axles
• for integration in gears or special-purpose machinery

The extremely compact and fully encapsulated MiniCoders provide two sinusoidal output signals phase-shifted by 90°, with an output level of 1Vpp. The standardised signal pattern is compatible with all NC controllers on the market.

By scanning a groove or flag, a reference signal can optionally be output (e.g. for positioning the spindle for changing tools).

The "Safety Integrated" certificate for Siemens controls is also fufilled. With a measuring frequency of up to 200 kHz, the MiniCoders can be deployed for speeds of over 100,000 r.p.m.

• Protection against condensation
• No wear and tear, maintenance-free
• Resistant to dirt, shock and vibrations

The controls used in machine tool manufacture are supplied via the 1Vpp interface with the signals from the GEL 2443 MiniCoder. The interpolation electronics integrated in the control increase the speed signalling resolution and make these signals available for the purposes of internal regulation. For changing tools, a unique spindle position is engaged. Exact referencing takes place using the reference signal supplied by the MiniCoder.

Where a 1Vpp interface is not available for the control in use, the GEL 2444 MiniCoder can be deployed with a 5V TTL output signal. Using internal interpolation, the resolution of the measuring system can be increased without additional external electronics.

Using a hobbing process, Lenord + Bauer manufacture target wheels with 0.3 or 0.5 modules. Almost 1000 variants have an inside diameter of 5–600 mm and an external diameter of 20–650 mm. Adjustments to meet specific conditions are completed quickly and precisely directly in our manufacturing facilities.

Interpolation electronics

Our interpolation electronics facilitate interpolation factors up to 512x as well as the conversion of sinusoidal 1Vpp signals into TTL or HTL square-wave signals.

Input signals: two sine/cosine signals phase-shifted by 90°, and their inverse signals Reference signal and inverse reference signal Output signals Two square-wave signals phase-shifted by 90°, and their inverse signals Reference signal and inverse reference signal Signal level 5V TTL or 10 … 30 V DC HTL

Test device

Our GEL 210 test device is used to test the output signal in the case of MiniCoders. The various parameters can be tested very easily. The various test values are selected automatically in sequence using sliding switches. The values can then be compared with specified tolerance values and thus verified accordingly.

The following are verified: Signal amplitudes Offset values Phase displacement Amplitude of the reference signal Position of the reference signal