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Ball Screw Drive
An LEFS slider, or rodless, type electric actuator features a load mounting platform situated above a ball screw drive. A flexible seal band permits platform movement while preventing grease and foreign matter from entering the drive. Advantages include a low profile height, shorter overall length than rod types, and better positioning repeatability than belt drives.
LEFS Electric Actuator, Slider Type, Ball Screw Drive
The original LEFS slider features an inline motor with a cover. Because the motor drives the ballscrew directly, additional cost of a belt and pulley system is avoided. The motor cover is taller than the load platform, so be aware of potential interference at the origin position.- Body sizes: 16, 25, 32, 40
- Maximum work load: 60 kg
- Maximum speed: 1200 mm/s (H lead, step motor, size 25 or larger)
- Stroke range: 50 to 1000 mm in 50 mm increments
- Positioning repeatability: ±0.02 mm
- Motor types: high load step motor or high speed servo motor

LEFS Electric Actuator, High Performance Slider, Ball Screw Drive
LEFS*F is a high performance version of the standard slider, equipped with a direct mounted, inline motor. Typical load capacities have increased 9-50%. Cycle time is dramatically reduced by a combination of higher maximum speed and acceleration/deceleration. Note that maximum speed gains are primarily in the 50-400mm stroke range, ranging from 5-36% faster depending on motor size and ballscrew pitch. A new high performance step motor controller, the JXC*H, pairs with the LEFS*F actuator. Actuator dimensions and mounting are identical to the standard LEFS, allowing an upgrade for existing equipment. I/O and actuator cables are also identical to the standard LEFS.
- Body sizes: 16, 25, 32, 40
- Maximum work load: 75 kg (horizontal); 25 kg (vertical)
- Maximum speed: 1500 mm/s (H lead, size 25)
- Maximum acceleration: 9800 mm/s²
- Stroke range: 50 to 1200mm in 50mm increments
- Positioning repeatability: ±0.02mm (±0.015mm high precision type)
- Motor type: 24 VDC step motor with incremental A/B phase encoder

LEFS Slider Type, Ball Screw Drive, Battery-less Absolute Encoder
The rodless LEFS slider is an electric actuator with a load mounting platform situated above a ball screw drive. A flexible seal band permits platform travel while preventing foreign matter from entering the drive. Slider advantages include a low profile height, shorter length than a rod with equivalent stroke, and better positioning repeatability than a belt driven slider. This version includes a 24VDC motor with a battery-less absolute encoder. This encoder allows the actuator to be powered down without losing its positional awareness. The machine's PLC can access the controller's operational and positional step data through several fieldbus protocols, IO-Link, or parallel I/O.
- Body sizes: 16, 25, 32, 40
- Maximum work load: 65 kg
- Maximum speed: 1200 mm/s
- Stroke range: 50 to 1200mm in 50mm increments
- Positioning repeatability: ±0.02mm, or ±0.015mm (high precision)

LEKFS*E High Rigidity Slider, Ball Screw Drive, Battery-less Absolute Encoder
The rodless LEKFS*E slider is an electric actuator with a load mounting platform situated above a ball screw drive. A flexible seal band permits platform travel while preventing foreign matter from entering the drive. Slider advantages include a low profile height, shorter length than a rod with equivalent stroke, and better positioning repeatability than a belt driven slider. LEKFS*E includes a redesigned guide with 4 rows of steel balls instead of 2, improving both allowable moment rigidity and positioning repeatability. Additional enhancements vs. the LEFS include auto switch mounting grooves, improved dustproof performance with magnetic seal band adhesion, standard positioning pin holes and drop-in upgrade replacement vs. LEFS. The LEKFS*E also features a 24VDC motor with a battery-less absolute encoder. This encoder allows the actuator to be powered down without losing its positional awareness. The machine's PLC can access the controller's operational and positional step data through several fieldbus protocols, IO-Link or parallel I/O.
- Body sizes: 16, 25, 32, 40
- Maximum work load: 65 kg
- Maximum speed: 1200 mm/s
- Stroke range: 100 to 600mm in 100mm increments
- Positioning repeatability: ±0.01mm, or ±0.02mm (high speed screw lead)
- Dynamic allowable moment: 8-61% improved vs. LEFS (size and axis dependent)

LEKFS*G High Rigidity Slider, Ball Screw Drive, High Performance with Battery-less Absolute Encoder
The LEKFS*G slider is the high performance version of the standard LEKFS*E. This motor upgrade improves the maximum work load, maximum acceleration, and maximum velocity compared to the standard motor. Lower cycle times can be realized with the higher performance. All other features of the LEKFS*E are included.
- Body sizes: 25, 32, 40
- Maximum work load: 75 kg
- Maximum speed: 1300 mm/s
- Stroke range: 100 to 600mm in 100mm increments
- Positioning repeatability: ±0.01mm, or ±0.02mm (high speed screw lead)
- Dynamic allowable moment: 8-61% improved vs. LEFS (size and axis dependent)

25A-LEFS Electric Actuator, Slider Type, Ball Screw Drive, Step Motor/ Servo Motor, Secondary Battery
The 25A- series variations are compatible with secondary battery manufacturing for electronics, automotive, and other vehicle types. Design goals include eliminating copper (Cu) and zinc (Zn) materials where possible, and employing a low dew point grease that retains lubricity even in low manufacturing temperatures. Please note that copper and zinc materials are used for the motors, cables, controllers and drivers.
- Same features and performance as standard LEFS
- Stainless steel bolts for construction
- Low dew point grease functional down to -70°C
- Copper and zinc free except for motor, cables and controller
- Non-standard materials for compatibility with secondary/rechargeable battery manufacturing