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100-214-276 Rev. 3
Chapter 2: Introduction to the 2000X aed Actuator
Welding Systems
Booster
Success in ultrasonic assembly depends on the right amplitude of movement at the horn face.
Amplitude is a function of horn shape, which is largely determined by the size and form of the
parts to be assembled. The booster can be used as a mechanical transformer to increase or
decrease the amplitude of vibrations applied to the parts through the horn.
The booster is a resonant half-wave section of aluminum or titanium. It is mounted between the
converter and the horn, as part of the ultrasonic stack. It also provides a clamping point for rigid
stack mounting.
Boosters are designed to resonate at the same frequency as the converter with which they are
used. Boosters are usually mounted at a nodal (minimum vibration) point of axial motion. This
minimizes the loss of energy and prevents vibration from being transmitted into the actuator.
Horn
The horn is selected or designed for a specific application. Each horn is tuned typically as a half-
wave section that applies the necessary force and vibration uniformly to the parts to be assem-
bled. It transfers ultrasonic vibrations from the converter to the workpiece. The horn is mounted
to the booster as part of the ultrasonic stack.
Depending on their profile, horns are referred to as stepped, conical, exponential, bar, or catenoi-
dal. The shape of the horn determines the amplitude at the face of the horn. Depending on the
application, horns can be made from titanium alloys, aluminum, or steel. Titanium alloys are the
best materials for horn fabrication due to their high level of strength and low loss. Aluminum
horns are usually chrome- or nickel-plated or hard-coated to reduce wear. Steel horns are for low
amplitude requiring hardness, such as ultrasonic insertion applications.
S-Beam Load Cell and Dynamic Follow Through
The S-Beam Load Cell measures the force being applied to the part to trigger ultrasonics and
record the welding parameters. The load cell assembly ensures that pressure is applied to the part
prior to the application of ultrasonic energy.
To maintain horn-to-part contact and force as the joint collapses, the load cell assembly provides
dynamic follow-through. As the plastic melts, the load cell assembly ensures smooth transmis-
sion of ultrasonic energy into the part.
Encoder
The encoder measures the distance the horn has travelled. Depending on the power supply set-
tings, it can:
• Allow for distance welding in absolute and collapse modes
• Detect improper setup controls
• Monitor the distance data of the weld
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