In the world of industrial automation, precision and adaptability are paramount. SCHUNK’s EZU Centric Grippers offer a versatile, high-performance solution for handling cylindrical parts and managing tough environments. With a unique 3-finger design, the EZU Centric Grippers deliver reliable and secure gripping, ensuring both efficiency and durability in every application.

This post will explore the features, benefits, and specifications of the EZU 30, EZU 35, and EZU 40 models, and how they can support seamless integration in a range of industries.

Why Choose SCHUNK’s EZU Centric Grippers?

SCHUNK’s EZU Centric Grippers are designed for flexibility and strength. Their 3-finger grip is optimized for eccentrically positioned workpieces, making them a top choice for handling cylindrical parts like shafts and gears in automotive and manufacturing settings.

Key Benefits of EZU Grippers:

• High Gripping Force: Reliable gripping strength across all three models, ideal for varying part sizes and weights.

• Sealed Design for Harsh Environments: With IP-rated sealing (up to IP64), EZU Grippers operate effectively even in environments exposed to dust, chips, or coolant.

• Easy Integration: Equipped with multiple communication interfaces (PROFINET, EtherNet/IP, EtherCAT, Modbus RTU, and IO-Link), these grippers are compatible with leading PLCs and robotic systems.

How does it work?

The EZU Centric Grippers use a powerful brushless DC servomotor that drives three gear racks in the base jaws. This motor works through a reliable spur gear unit, using a rack-and-pinion mechanism to ensure consistent gripping force. Even if there’s a slight misalignment of the workpiece or robot, the EZU grippers maintain a strong, centered hold with high fault tolerance.

Another advantage is that the grippers don’t require a specific approach distance to initiate grip. This design speeds up handling and keeps operations smooth. With an integrated absolute encoder, the grippers are ready to go immediately after an emergency stop or power outage. Additionally, the gripping force is maintained by a permanent magnet brake and a damping element in the drive train, minimizing the risk of workpiece loss, which is quickly detected by the built-in workpiece loss detection system.

Technical Specifications for Each Model

Understanding the differences among the EZU 30, EZU 35, and EZU 40 can help you select the right fit for your application. Here’s a quick breakdown:

Features That Set EZU Grippers Apart

Each EZU Centric Gripper is packed with features to boost productivity and provide seamless integration into your automation systems.

1. Reliable 3-Finger Gripping Mechanism

The 3-finger design offers a balanced and secure grip, ideal for cylindrical parts that require high precision. This mechanism allows for more consistent handling and a high tolerance for positioning errors, making it reliable for repetitive tasks.

2. Advanced Connectivity and Compatibility

SCHUNK’s EZU Grippers support multiple communication protocols, ensuring compatibility with a wide range of PLCs and robotic systems, including those from Universal Robots, FANUC, and YASKAWA. They also include seamless integration tools:

• PLC and Robot Integration: Easily connect using PROFINET, EtherNet/IP, or Modbus RTU protocols, which reduces setup time and allows for direct system control.

• Diagnostics and Commissioning Tools: With the SCHUNK control center app, you can manage firmware updates, adjust settings, and perform diagnostics without a PLC, streamlining the setup process.

3. Dual Gripping Modes

Each gripper offers two specialized gripping modes:

BasicGrip: The gripping speed is automatically optimized for gripping force adjustment, permanent re-gripping is possible

StrongGrip: Maximum gripping force is generated and then stored by the gripping force maintenance, permanent re-gripping is possible within an adjustable time window, pause times between gripping cycles must be taken into account

4. Enhanced Reliability with Smart Design

With its sealed T-slot guidance and IP-rated protection, the EZU series performs consistently in environments with exposure to dust, debris, or fluids. Plus, the grippers feature an absolute encoder, which maintains the jaw position for immediate restart after power outages, further enhancing productivity and reliability.

Real-World Applications

The EZU grippers excel in high-demand environments where precision and durability are essential. Here are a few examples of their applications:

• Machine Loading and Unloading: With their strong grip and consistent performance, EZU grippers handle both raw and finished parts in a single loading cycle. This dual capability reduces machine downtime and optimizes production rates.

• Harsh Environments: The dust-tight and moisture-resistant versions of EZU grippers allow them to thrive in challenging conditions like grinding or sanding, where other grippers might struggle.

Customization Options and Accessories

SCHUNK provides several accessories to extend the functionality and versatility of the EZU Centric Grippers:

• Robot Adaptation Kits: Available for single or double grippers, these kits include everything needed to fit the EZU grippers to popular robot models, including adapters and mounting kits.

• Quick-Change Systems and Customizable Jaws: Optional quick-change systems and customizable gripper fingers are available to ensure that each gripper meets specific application requirements, saving time and boosting efficiency.

Conclusion

SCHUNK’s EZU Centric Grippers offer a versatile, robust, and high-precision solution with a unique 3-finger gripping design. These grippers simplify handling for cylindrical and eccentrically positioned workpieces, ensuring reliability in harsh environments and adaptability for diverse applications. From easy integration to exceptional gripping force, the EZU series is engineered to deliver value in any automated workflow.

For more insight into similar equipment, explore the SCHUNK O-Ring Gripper and the SCHUNK Machine Tending Bundle.

EZU Centric Gripper Notes

Housing material: Aluminum alloy, anodized

Base jaw material: Steel, corrosion-protected

Warranty: 24 months or 5 million cycles BasicGrip / 3 million cycles StrongGrip (one cycle consists of a complete gripping process: "Open gripper" and "Close gripper")

Scope of delivery: Gripper including safety information and accessory kit with centering sleeves for gripper and finger mounting. Product-specific instructions and software can be downloaded at schunk.com/downloads-manuals and schunk.com/downloads-software.

Gripping force: is the arithmetic sum of the individual force applied to each jaw at distance P (see illustration).

Repeat accuracy (gripping): defined as the spread of the actual position during 100 consecutive closing or opening movements on a rigid workpiece or a fixed workpiece stop under constant conditions.

Repeat accuracy (positioning, unidirectional): defined as the spread of the actual position per base jaw during 100 consecutive movements to a target position from the same direction under constant conditions.

Repeat accuracy (positioning, bi-directional): defined as the distribution of the actual position per base jaw during 100 consecutive movements to a target position from both directions under constant conditions.

Finger length: is measured from the reference surface as the distance P in direction to the main axis.

Closing and opening times (positioning): Closing and opening times are only the movement times of the fingers at max. speed, max. acceleration with observance of the maximum permissible masses per finger and refer to 50% of the available stroke per jaw in the basic version.

Max. speed (positioning) and max. acceleration: is the speed and acceleration acting on each jaw.

Application example - Flexible, cycle-time optimized loading and unloading of a machine tool. By using two grippers on the robot, the machine tool can be automatically loaded in a way that is optimized in terms of cycle time, meaning that productivity can be increased. Finished part and pre-machined part can be transported in one loading cycle. Due to the large and freely programmable jaw stroke of the gripper, different diameters can be gripped without having to change the gripper.

SCHUNK Accessories - The following components make the product even more productive – the suitable addition for the highest functionality, flexibility, reliability, and controlled production.

• Power Cable
• Communication Cables
• Intermediate Jaw
• Robot Adaptation Kits
• Robot-Specific Connection Cables
• Customizable Gripper Fingers
• Finger Blank
• Jaw Quick-change System

Options and special information

Gripping modes: The BasicGrip and StrongGrip gripping modes are available. With BasicGrip continuous operation of the motor and thus permanent re-gripping of the workpiece is possible. The gripping speed is automatically optimized for gripping force adjustment. With StrongGrip, the maximum gripping force is generated and then stored by the gripping force maintenance. Permanent regripping is possible within an adjustable time frame. In addition, defined pause times and maximum ambient temperatures must be taken into account in StrongGrip mode. Further details can be found in the operating manual.

Gripping force maintenance: In the event of an emergency stop or a voltage drop, more than 80% of the originally applied gripping force can be reliably maintained due to a combination of an electric holding brake and the initial tension of the elastic element. If the gripping force and position maintenance is activated preventatively, 100% of the originally applied gripping force can be maintained. Overrun of the gripper fingers when removing the workpiece is a few millimeters and depends on the gripping force generated. Variants without gripping force maintenance are also available as an option.

Seal: The gripper comes standard with enhanced protection against the ingress of dust or liquids. The IP protection of the electronics is only given if the plug connectors have been mounted properly. The gearbox of the gripper is additionally protected by a seal on the output pinions.

Interface of the base jaws: When the intermediate jaw is used, the interface of the base jaws corresponds to that of the universal gripper PZN-plus. This means that the extensive range of finger accessories for the PZN-plus can also be used for this gripper, taking into account the interfering contours, and the application limits that apply.