Technical Information
Glossary of Ultrasonic and Thermal Welding Terminology
Air Controls
Adjusts the force being applied to the parts during the weld cycle.
Amorphous
A polr with ayme random molecular structure of chains that vary in length. Vibratory
energy can easily be transmitted through amorphous polymers.
Amplitude
Refers to vertical, vibratory, peak-to-peak movement produced by the convertor,
modified by the booster and fine-tuned by the horn.
Booster
A device used to modify the convertor generated amplitude by either increasing
or decreasing it before it gets to the horn.
Boss
A raised portion of the workpiece, usually a circular, hollow feature for pin
location and insertion.
Clearance
Allowing room for the plastic to flow in the joint design.
Convertor
Converts high-frequency electrical energy into high-frequency mechanical vibratory
energy.
Copolymer
A combination of two different resins joining to make one polymer.
Crystalline
Polymers with a an orderly arrangement of molecules that repeat in precise patterns.
The spring-like molecules tend to absorb energy making it more difficult to
transmit vibratory energy through it.
Cycle counter
Counts the number of parts assembled.
Degating
To remove the mold gate or runner on a part that is created during the mold
process.
Down platen button
Used in conjunction with setup key, this button will lower the platen to the
part.
Dwell timer
Adjusts the amount of time that pressure is held on the parts during the weld
cycle.
Emergency stop button
Completely disables all funtions of the machine.
Energy director
Typically a triangular-shaped ridge molded into one of the mating plastic parts.
This ridge limits initial ultrasonic contact to a very small area. The ridge
melts during ultrasonics causing plastic to flow through the joint bonding the
parts together.
Far field
Refers to parts having an interface more then 1/4" from the contact surface
of the ultrasonic horn.
Fixture
An automatic or manual holding device used to secure the parts being assembled.
Flash
Refers to molten plastic that seeps out of the joints.
Flow control adjustments
These control valves are used for fine tune adjustments on movements that utilize
air flow.
Guard
A clear plexy covering of the thermal tooling, which protects the operator from
getting injured.
Heat on/off switch
Turns the heat probes on.
Hermetic seal
An ultrasonically welded seal that is air and water tight under pressure.
Homopolymer
Refers to a polymer made up of just one resin.
Horn
A precisely shaped and tuned piece of material, usually aluminum or titanium,
attached to the booster which transfers the ultrasonic energy to the part being
welded.
Hz
Refers to the number of cycles per second. 20 kHz means 20,000 cycles per second
Inserting
Embedding metal components such as inserts into preformed holes in a thermoplastic
part.
Interface
The area where two mating parts contact each other.
Jack-out
Refers to the amount of force it would take to disassemble inserts that have
been ultrasonically inserted.
Joints
The point at which two thermoplastic parts connect. The four most used joints
in ultrasonic assembly are Butt, Step, Shear, and Tongue and Groove.
Linear encoder
An ultrasonic welder accessory which detects the precise height location of
the welder head. The welder can be programmed to weld to certain depths during
staking or inserting with the use of this device.
Microprocessor
A computerized controller of an ultrasonic welder that provides precise control
over weld parameters such as energy, time and pressure.
Mode of operation switch
The switch is used by the set-up operator. In set-up mode the machine settings
can be adjusted. In Run mode the machine settings are locked.
Near field
Refers to parts having and interface less then a 1/4" from the contact
surface of the ultrasonic horn.
Piezoelectric crystals
Material which changes dimension when electrical energy is applied to it. The
change in dimension coincides with the frequency of the alternating current
which causes a vibration or conversion to mechanical energy.
Platen pressure gauge
Measures the force being applied to the parts.
Post cool adjustment knob
Main power. This button overrides all other on/off switches.
Photo-electric palm buttons
Push these 2 buttons to start the weld cycle. Both buttons must be touched at
the same time in order for the welding head to come down. This is a safety mechanism
to prevent injury.
Power supply
Converts standard, 50/60 Hz, alternating current to high-frequency electrical
energy above 15,000 Hz. Power supplies are available in different power wattages,
usually between 200 - 4,000 watts.
Resin
Chemical compounds which make up plastic polymers. These polymers are divided
into the following two categories: Amorphous and Crystalline.
Spot welding
Assembling thermoplastics without preformed holes or energy directors. This
method is useful for large parts and sheets of extruded or cast thermoplastics.
Staking
The process of melting and reforming a thermoplastic post to lock a dissimilar
material in place mechanically.
Swaging
Capturing another component of an assembly by ultrasonically melting and reforming
a ridge of plastic over the other material.
Tempature controllers
These controllers set the tempature for each of the individual heating zones.
Terpolymer
A combination of three different resins which make up one polymer.
Thermal Tooling
This consists of the heating probes and tips that are designed to heat stake,
insert, swage, degate, emboss, date code, or decorate the parts.
Thermoplastic
Plastic which can be remelted and reformed with the introduction of heat and
pressure.
Ultrasonic welding
Ultrasonic vibration in excess of 15,000 Hz creates heat and melting of plastic
at the interface of two thermoplastic parts. When the vibration stops, the molten
plastic resolidifies bonding the parts together.
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