New LEJ range electrical actuators: more precise, quicker and suitable for clean rooms

Die neuen elektrischen Antriebe der LEJ-Serie von SMC: mehr Optionen, höhere Positioniergenauigkeit, mehr Auswahl beim Hub und auch mit Reinraumspezifikation. (Foto: SMC Pneumatik GmbH)

SMC is increasing its offer of LEJ range electrical actuators with many models: for example, the LEJSH precision model offers a much improved positioning accuracy of ± 0.01 millimetres. Many new models have the prefix 11 in their name. They are suitable for use in ISO 4 class clean rooms. New LEJS40/63 type models have higher spindle pitches and thus 50% higher maximum speeds. As part of the expansion of the range, the standard stroke variants have been much more narrowly graduated. All actuators of the LEJ range are equipped with a double linear guide which can handle eccentric loads and reduce deviations. They offer a high degree of rigidity and are suitable for industrial plants with any kind of transfer and assembly use. A low casing cross-section and load centre of gravity also make the actuator very compact.

Options & extensions in detail

The new electrical actuators of the LEJSH range offer an improved positioning precision of ± 0.01 mm compared to their equivalents in the LEJS range, which offer ± 0.02 mm. The no-load running was also reduced from max. 0.1 mm to max. 0.05 mm. They are also available in a clean room version.

Versions with a higher spindle pitch are now offered for the new actuator spindles in the sizes LEJS40 and LEJS63. The maximum speeds have thus been increased from 1,200 to 1,800 mm/s. The following are available:

- LEJS40: spindle pitch 24 mm, maximum speed 1,800 mm/s.
- LEJS63: spindle pitch 30 mm, maximum speed 1,800 mm/s.

All models of the LEJS range are now also available as clean room versions. With a total of 26 new standard stroke variants, the LEJS as well as the LEYB ranges were clearly graduated more narrowly. Users can now choose from 44 standard actuators. All models are also available in the standard strokes of 400 mm, 700 mm, and 900 mm. At the highest level, the LEJB40 and LEYB63 actuators are also available with a standard stroke of
1,500 mm, 2,000 mm or even 3,000 mm (LEJB63).

Two actuator types for higher loads or more speed

SMC uses the suffix S or B to differentiate the actuator types of the LEJ range of electrical actuators. LEJS refers to versions with a ball screw which can handle horizontal work loads up to 85 kg.

LEJB refers to versions with quicker belt actuators. With a maximum speed of up to 3,000 mm/s, horizontal loads up to 20 kg can be moved with a position repeatability of ± 0.04 mm. Regardless of the type of actuator, the attainable accelerations/decelerations are 20,000 mm/s².

Regarding installation, the actuators of the LEJ range are characterised by the little effort required. They are attached to the main casing. The outer casing does not need to be removed. The electronic signal transmitter of the D-M9 and D-M9W ranges with a two-coloured actuator help to find the right signal transmitter position. LEJ actuators are equipped with high-performance AC servo motors with incremental or absolute encoders. A large selection of servo amplifiers ensures fast commissioning. All actuators can also be equipped with motors from many reputable manufacturers in the "open flange – no motor" version.

Application areas

The LEJ range electrical actuators from SMC are perfect for general industrial plants such and pick and place applications, loading and unloading work pieces (vertical and horizontal transfer), high speed tracking controls or the application of adhesive. The prefix 11 denotes a clean room version. These models are equipped with a connection for vacuum pumps. Abrasion, which can happen in case of continual operation of the actuators, can be sucked off and discharged immediately. Important applications for these model versions are, for example, in the semi-conductor and LCD industry.