SCHUNK EZU Electric 3-Finger Centric Gripper Review: Specs, Price and Applications
The SCHUNK EZU is a servo-electric three-finger centric gripper built for round and cylindrical parts. A brushless DC servomotor drives three racks through a spur gear, so all three fingers close concentrically on the part axis and the gripping force stays nearly constant along the finger length.
Control electronics are integrated into the housing, an absolute encoder reports finger position without a homing run, and a permanent-magnet brake works with a pre-tensioned elastic element to hold the workpiece if power drops. The sealed, slide-guided design targets machine tending around CNC lathes and mills, where coolant and chips are part of the daily environment.
Quick Verdict
A strong choice when a cell needs repeatable centric gripping of shafts, flanges or turned parts with electrical control instead of compressed air. Its grip-retention concept and absolute position feedback make it particularly well suited to unattended machine tending.
SCHUNK EZU Electric 3-Finger Centric Gripper at a Glance
Specification | Details |
Gripper type | Electric 3-finger centric gripper |
Drive | Brushless DC servomotor, spur gear and three gear racks (rack-and-pinion) |
Gripping force profile | Nearly constant along the finger length |
Position feedback | Absolute encoder; no minimum approach distance |
Grip retention on E-stop or voltage drop | More than 80% of the original gripping force (electric holding brake plus elastic pre-tension) |
Grip retention with preventive activation | 100% of the original gripping force |
Workpiece monitoring | Integrated workpiece-loss detection |
Gripping modes | BasicGrip or StrongGrip, selected by ordering code |
Construction | Sealed, slide-guided; intermediate jaws compatible with the PGN-plus-P interface |
Price | Request a quote |
Design and Operating Principle
Three racks driven by one spur gear give the EZU synchronized concentric motion. That geometry is what makes a centric gripper useful for turned parts: the workpiece axis is pulled onto the gripper axis during closing, which reduces the positioning tolerance the robot has to hold when loading a chuck.
Because the motor and electronics sit inside the module, cabling is reduced to power and communication, and gripping force and position are set in software rather than by pressure regulators. The absolute encoder means the controller knows finger position at power-up, so a cell can resume after an interruption without a reference move.
Grip retention is handled mechanically. A permanent-magnet brake and a pre-tensioned elastic element keep more than 80% of the force during an emergency stop or voltage drop, and activating the retention function before a stop keeps the full force. When the part is released, the fingers overrun by a few millimeters depending on the force applied, which should be allowed for in fixture and chuck clearances.
Integration and Selection
Size the EZU from the workpiece mass, the finger length and center-of-gravity offset, and the accelerations of the robot path, then check the permitted finger moments for the chosen size. Long or heavy custom fingers reduce the usable force and load capacity.
Plan the control interface early: the gripper's integrated electronics have to be mapped into the robot or PLC program, including grip, release, part-present and part-loss signals. For machine tending, align the gripping stroke with the smallest and largest diameters in the part family so that one set of fingers covers the job.
Industry Applications
Industry | Typical use |
Automotive powertrain | Loading shafts, gears and bearing rings into CNC lathes |
Precision engineering | Transferring turned components between machining operations |
Hydraulics and fluid power | Handling valve bodies and round fittings at grinding cells |
Metalworking job shops | Unattended loading of bar-cut blanks and finished parts |
Functional Uses
Centering cylindrical workpieces on the gripper axis before chuck loading
Internal or external gripping of rings and sleeves
Part-present and part-loss monitoring during transfer
Software-adjusted gripping force for mixed part families
Holding the part safely through an emergency stop
Pros and Cons
Advantages
Concentric 3-finger motion centers round parts automatically
Absolute encoder removes the need for homing
More than 80% grip retention on power loss, 100% with preventive activation
Sealed design for coolant and chip environments
No compressed air required
Limitations
Higher module cost than a comparable pneumatic 3-jaw gripper
Finger overrun of a few millimeters on release must be designed in
Integration requires mapping the electronic interface into the robot or PLC
Who Should Consider the SCHUNK EZU Electric 3-Finger Centric Gripper?
Consider the SCHUNK EZU for CNC machine tending, turned-part handling and any cell that grips round parts repeatedly and must stay safe through stops and power interruptions. Teams moving away from compressed air, or running high-mix part families that need adjustable force, will get the most from it.
Price and Availability
Price: Request a quote. SCHUNK prices the EZU by size, options and quantity, so the final figure depends on the exact ordering code. Budget for the complete tooling package, including fingers or adapters, mounting, cabling or pneumatics and commissioning time, rather than the module alone.
Further Reading
SCHUNK EZU Electric 3-Finger Centric Gripper FAQ
What is the SCHUNK EZU?
The SCHUNK EZU is an electric three-finger centric gripper with integrated control electronics, designed for gripping round and cylindrical workpieces in machine tending and assembly.
How does the EZU hold a part during an emergency stop?
A permanent-magnet brake and a pre-tensioned elastic element keep more than 80% of the original gripping force during an emergency stop or voltage drop. With preventive activation before the stop, 100% of the force is retained.
Does the EZU need a homing run after power-up?
No. The absolute encoder provides the finger position at power-up, so the gripper can continue without a reference move.
Which applications suit the EZU best?
CNC lathe and mill tending, transfer of turned parts, and handling of shafts, rings and flanges where concentric centering is an advantage.
Can the EZU use existing fingers?
Its intermediate jaws are compatible with the PGN-plus-P interface, which simplifies reuse of finger designs and standard accessories.
What does the SCHUNK EZU cost?
Pricing depends on size, gripping mode and control variant. Request a quote from SCHUNK or an authorized distributor for the exact configuration.
