A new standard

Incremental encoders have become firmly established in factory and process automation as well as in many other applications for position detection and speed measurement. However, the requirements that users place on the sensors are as varied as the areas of application. Finding the right encoder for every application is therefore not necessarily easy, since there is no such thing as an "egg-laying pillow", even in the case of incremental encoders. A modular product design is therefore practical, thanks to which individual requirements can be met at an attractive price/performance ratio and within a short time.

The basis for the modular product design is a corresponding system construction kit, which offers great flexibility and at the same time high economic efficiency for the user. With OptoPulse, Baumer is now presenting a new generation of incremental rotary

Practical modular system

encoder, which is based on a sophisticated modular system. The modular product design was developed as a new standard for the widely used 58 mm diameter and provides the starting point for numerous encoder variants that can be flexibly adapted to a wide range of requirements.

Many mechanical and electrical connection variants

Users specify the required encoders not only in terms of performance, but also in terms of mounting options, because application and mounting conditions can vary considerably. Until now, numerous encoder series covered these different requirements. With the new, modular series, things are now simpler, clearer and more universal. For example, there are now clamping or servo flanges or versions with

Clear and universal

hollow shaft from 8 to 15 mm diameter within a product family. Depending on the version and shaft seal, the encoders are designed for operating speeds of up to 12,000 rpm.

For the electrical connection, either M23 or M12 connectors are available, as well as versions with radial or axial cable outlet, which is particularly popular in tight installation conditions. A tangential cable outlet will also be available in the first half of the year, which enables particularly space-saving installation in the fan guard of asynchronous motors, for example, since the cable virtually hugs the encoder. Depending on the application, the cable can also be used in radial or axial direction. The cables are available as standard in 1 or 2 m lengths. However, the modular design also allows other lengths and cable assemblies without further ado, for example 0.5 m length with pre-assembled connector. There is also a practical choice of operating voltage and output stages. Thanks to the integrated reverse polarity and short-circuit protection, the encoders are electrically safe from installation errors.

Precision in rough industrial use

For position detection and speed measurement in factory and process automation, but also, for example, on wind turbines, in elevators, packaging or printing machines.

Optimum concentricity and axial runout

encoders sometimes have to deliver precise measurement results even under very harsh environmental conditions and prove their reliability to prevent malfunctions and costly machine downtimes. The mechanics, scanning and electronics of the opto-pulse encoders take these requirements into account.

An important basis for optimum radial and axial runout is the carefully and precisely manufactured mechanism with two tensioned quality bearings. The ShaftLock bearing design, which has been tried and tested for over 15 years and is used in both solid and hollow shaft designs, is designed to function reliably and without failure even under the most adverse conditions. The design incorporates large dimensioned quality ball bearings with maximum spacing and prevents displacement of the bearing pack due to excessive axial shaft loads during operation or already during installation.

After all, many an encoder has been damaged during assembly because an overzealous employee took a hammer to it. Even in such cases, the bearing design prevents damage to the code disk or scanning unit and protects against costly downtime and repairs. The maximum permissible bearing loads are 40 N axially and 80 N radially.

Optical sensing operates over the entire temperature range from - 40 to + 85° C with high accuracy and consistent signal quality. The basis for this is a monolithic opto ASIC with high integration density, which is specifically designed for use in precision encoders. The exact graduation of the code disk ensures reliable measurement results without interpolation errors; the finely graduated line counts per revolution currently range from 100 to 5000.

By reducing the number of discrete components, the reliability of the application in terms of shock and vibration has been significantly increased. The encoders are shock-resistant up to 300 g (in accordance with DIN EN 60068-2-27, 6 ms) and can withstand vibrations up to 30 g (in accordance with DIN EN 60068-2-6, 10 to 2000 Hz), making them suitable for applications where the going gets rough, e.g. on presses, in steel construction or on wind turbines. The entire electronics are also absolutely resistant to strong magnetic fields, such as those to be expected in the environment of magnetic brakes.

Design details with practical benefits

Other design details also contribute to the reliability and durability in industrial use. The thick-walled metal housing protects the encoder from environmental influences and at the same time makes a decisive contribution to EMC compatibility. Shafts and clamping rings do not consist of cast parts, but are made of solid material, which ensures a secure mechanical connection even under unfavourable conditions. The plugged-in PCB connection improves the shock and vibration properties and thus makes a decisive contribution to high operational reliability. In contrast, mechanical stresses and natural ageing processes of the solder alloy used can lead to malfunctions with the otherwise usual soldered connections, especially in the case of permanent temperature fluctuations or vibrations.

Both solid shafts are flattened and thus ensure a positive connection, for example with a mounted measuring wheel or a shaft coupling.

Facilitated assembly and integration

All hollow shafts are slotted to provide a secure fit on the shaft, reduce vibration and allow higher shaft tolerance. The encoders meet the requirements of protection class IP65 as standard and IP67 with additional shaft sealing. The matching, optimally dimensioned and precisely matched accessories facilitate mounting and integration into the respective application. Thanks to this "everything from a single source" principle, the interaction between the encoder and accessories functions smoothly. The extensive range of accessories includes different mounting brackets, stator couplings and torque supports as well as measuring wheels or bellows, spring washers and double-loop couplings that meet a wide variety of application requirements.

Lean processes and fast availability

However, the modular encoder design offers even more advantages, because in combination with new technologies and lean manufacturing processes, it not only ensures an attractive price/performance ratio, but also fast availability. The user benefits from the short delivery times not only for new products, but also for replacements. Numerous stock types can be delivered in single units within 24 hours or within one working day from the production plant, other preferred types up to a quantity of ten encoders within five working days. This will also help to ensure that the new encoders will find many areas of use as a new standard in factory and process automation as well as in other applications such as wind turbines, in elevator technology or in packaging or printing machines; and thanks to the modular product system, the application possibilities will be constantly expanded with each future variant.