High Power Ultrasonic Transducers with Two Parallel Stacks for Welding

Ultrasonic transducers are piezoelectric ceramics that resonate at ultrasonic frequencies and convert electrical signals into mechanical vibrations by the piezoelectric effect of the material. When the transducer is used as a transmitter, the electrical oscillating signal sent from the excitation source will cause a change in the electric or magnetic field in the electrical energy storage element of the transducer, which changes the mechanical vibration system of the transducer through some effect. A driving force is generated to cause it to vibrate, thereby propelling the medium in contact with the mechanical vibration system of the transducer to vibrate and radiate sound waves into the medium.

Clustered transducers

Clustered transducers can be used to drive a single ultrasonic stack. Compared to a single large diameter transducer, each of the smaller transducers has smaller diameter piezoceramics which potentially allows a more uniform piezoceramic prestress.

Because the piezoceramics have smaller diameters, the radial thermal conduction path for the piezoceramic heat will be smaller. Then the heat can be conducted more easily to the piezoceramic periphery so the piezoceramics should remain cooler for a given convective air flow.

In addition, smaller piezoceramics will allow greater peripheral area for convective air cooling. For example, consider a simplified transducer that uses a single Ø50 mm x 5 mm thick piezoceramic. (Here, any center piezoceramic bore is ignored.) The piezoceramic volume is 9818 mm³ ａnd the peripheral area is 785 mm². Now assume that this transducer with the single piezoceramic is replaced by two transducers that have the same total piezoceramic volume (again assuming only one piezoceramic for each transducer). With this stipulation, the required piezoceramic diameter is 35.4 mm and the resulting total peripheral piezoceramic area is 1112 mm². In this example, using a dual transducer system increases the total peripheral piezoceramic area by 42% which may result in significantly improved cooling, thereby permitting higher power through-put.

High Power Ultrasonic Transducers with Two Parallel Stacks for Welding 

Ultrasonic welding is used across variety of industries to join together thermoplastic materials. During ultrasonic welding, high frequency mechanical vibrations and compressive pressure are applied to the plastic materials. This creates intermolecular friction within the plastic which raises the temperature high enough to reach the melting point. During high volume production in manufacturing environments, the ultrasonic welding system component which fails most often is the transducer, which is responsible for creating the vibration. The transducer converts electrical energy into mechanical energy by means of a polarized piezoelectric PZT (lead zirconate titanate) polycrystalline ceramic material using high frequency voltage. The transducer is composed of round PZT disks attached to a titanium machined body by means of a central bolt. The bolt creates compressive pre-stress which prevents any tensile stresses within the brittle crystals during vibration and ensures perfect coupling between all components. The piezoelectric PZT crystals behave according to linear coupled electrical and mechanical equations. The transducer assembly is vibrated near the parallel resonant frequency to maximize efficiency and amplitude output.

Service and shipment 

l Warranty one year for transducer.

l You can contact us for technical inquiry any time.

l We supply OEM service for oversea customer, also will keep Confidentiality for our customers.

l We supply customized products service for small quantity also.

l Shipment by FED-EX /DHL