Glossary of Terms
Adhesive bonding: the ultrasonic system is used to activate an adhesive on a tape thereby permitting the joining of parts that are not usually considered weldable with ultrasonics alone.
Anvil: the backup piece that positions and supports the parts being welded, sometimes called welding nest.
Booster: is adjacent to the converter. The booster increases the amplitude of vibration. In Sonobond’s metal welding system the booster is referred to as the wedge because of its wedge shape.
Converter (transducer): contains piezoelectric crystals that convert the high frequency electrical signal to mechanical vibration
Clamping force: the force exerted on the part being welded by the action of the pneumatic cylinder.
Distance measurement: requires a distance measuring device in the welder head. Can measure pre-weld height and the compression of the part after it is welded.
Energy: product of the power and the time of application, usually expressed in watt-seconds or joules.
Horn: delivers the vibration to the parts being welded.
Kilohertz (kHz): the frequency of the signal. One kilohertz is one thousand cycles per second.
Kilowatts (kW): the power rating of the system. One kilowatt is one thousand watts.
Lace and pattern making: patterned trim can be made on synthetic fabrics by the action of the ultrasonic system and a special rotary pattern roller.
Mass: the large block above the reed which is attached to the slide and the pneumatic system.
Nest: the tooling which supports or positions the parts to be welded, also referred to as the anvil.
Pattern roller: for rotary textile bonding the pattern roller embosses or cuts a pattern or stitch and backs up the film or fabric being bonded.
Power supply: plugs into line power and changes the electrical signal to the high frequency, high voltage needed to drive the ultrasonic system.
Plunge welding/cutting: the welding, or cutting, action takes place in a single pulse. The bond area or cut pattern is determined by the size and shape of the horn and anvil.
Reed: in Sonobond’s metal welders, the reed is the vertical rod which holds the welding tip and also is the element attached to the wedge.
Repeatability: the ability of a process to produce results which are essentially the same when other process parameters are held constant. Also referred to as a robust process or controlled process (or expressed in statistical terms as CpK).
Seam welding: continuous seam welds are produced when a roller is rotated and traversed across the material to be bonded while ultrasonic energy is applied.
Shear mode: when the high frequency vibration is directed in a plane parallel to the welding surface while the line of force is directly over the welding surface. The shear mode is necessary for metal welding but not for plastic welding.
Sonotrode: the ultrasonic welding tip.
Spot welding: spot welds may be circular, elliptical, rectangular, annular, etc. in geometry. They are formed when the material is clamped between the shaped tip and anvil and ultrasonic energy is applied.
Taper lock tip: used with the wedge-reed system, the taper lock tip is a one-piece welding tip with a shallow locking taper (Morse taper) which fits into a matching tapered receptacle in the reed. This provides a low cost, replaceable tip usually made of heat treated steel which can be readily oriented before locking into place.
Trigger: the variable or event which causes the ultrasonic energy to fire or trigger, usually by preset pressure reached or time after cycle is started.
Ultrasonic: frequency above the normal hearing range, generally accepted to be above 17 kilohertz, and typically 20 kHz or higher.
Ultrasonic bonding/welding: the use of high frequency vibratory energy combined with pressure to effect a bond or weld in plastics, synthetic textiles or certain metals.
Wedge-reed: assembly consisting of the wedge, and the reed which transmits the ultrasonic energy to the welding tip, and the mass block through which the force is applied. Patented technology which provides low amplitude, high vibratory force to the metals which are to be welded.
Textiles and plastics may be bonded if the materials are thermoplastic, and compatible materials are to be joined. Weldable materials include polyester, polyethylene, polypropylene, acrylics, nylon, polycarbonate, acetate, ABS etc. For ultrasonic welding the materials should be at least 50% synthetic.
Weldable metals are usually non-ferrous alloys typically copper and aluminum alloys. Part configuration can be sheet metal or wire to wire or wire to terminal, also tubing up to 3/8-inch (9mm) diameter can be sealed without crimping and brazing.