ASML 851-0618-003 Stepper Library Brake – Reliable Holding and Deceleration for Lithography Motion

The ASML 851-0618-003 is a stepper library brake assembly engineered for ASML lithography systems. This brake provides reliable holding and deceleration functions for various motion axes, including wafer stages, reticle stages, and transfer mechanisms. Its robust construction and precise actuation ensure safe and accurate positioning, which is critical for maintaining high overlay accuracy and process integrity.

Overview of the Brake Assembly

The library brake is a spring‑applied, electrically released brake that engages automatically when power is removed, preventing unintended axis movement. It is used in applications where holding torque is required during power‑off conditions or emergency stops. The brake's design minimizes backlash and provides consistent braking torque over its service life.

Technical Specifications

• Part Number: 851-0618-003

• Product Type: Stepper library brake

• Brake Type: Spring‑applied, electromagnetic release

• Holding Torque: 2.5 N·m

• Release Voltage: 24 VDC

• Power Consumption: 5 W

• Response Time: 50 ms (release), 30 ms (engage)

• Mounting Style: Flange mount with pilot diameter

• Shaft Diameter: 12 mm

• Operating Temperature: 5 °C to 45 °C

• Protection Class: IP40

• Dimensions: 60 mm diameter x 40 mm length

• Weight: 0.6 kg

Functional Principle

In its de‑energized state, a spring forces the brake friction disc against a stationary plate, generating holding torque. When voltage is applied, an electromagnet pulls the friction disc away, releasing the shaft. This fail‑safe design ensures that the brake engages automatically in the event of power loss.

Application Areas

Used in wafer stage axes, reticle stage axes, and load/unload mechanisms to prevent drifting and maintain position during idle or emergency conditions.

Installation and Adjustment

Installation involves mounting the brake onto the motor or shaft flange and connecting the electrical leads. Air gap adjustment may be required to ensure proper engagement.

Maintenance

Periodic inspection of the friction surfaces and electrical connections is recommended. Replacement of worn friction discs may be necessary after extended use.

Compliance

Complies with CE and RoHS standards.

Conclusion

The ASML 851-0618-003 stepper library brake provides reliable holding and safety functions essential for precision lithography motion systems.