A piezoelectric device is a type of transducer that can convert electrical energy into mechanical energy and vice versa. It operates based on the piezoelectric effect, which is the ability of certain materials to generate an electric charge in response to applied mechanical stress, or to deform when subjected to an electric field. This unique property makes piezoelectric devices valuable in a wide range of applications, including pharmaceutical printing.
In pharmaceutical printing, a piezoelectric device can be used to control droplet ejection in inkjet printing systems. Here's how it works:
Ink Reservoir and Nozzle Setup: The pharmaceutical liquid (ink) is stored in an ink reservoir. This reservoir is connected to a tiny nozzle through which the droplets are to be ejected. The nozzle is typically very small, often in the micrometer range, allowing for precise control over droplet size and placement.
Piezoelectric Actuator: A piezoelectric actuator is positioned near the nozzle. This actuator consists of a piezoelectric material, which can undergo mechanical deformation when an electric voltage is applied to it. The actuator is usually designed in such a way that the deformation results in a change in the size or shape of the nozzle.
Droplet Ejection Process: To eject a droplet, a voltage is applied to the piezoelectric actuator. This voltage causes the actuator to deform, which in turn changes the shape of the nozzle. As the nozzle changes shape, it can create pressure changes within the ink chamber, leading to the ejection of a droplet from the nozzle. The size of the droplet and the velocity at which it is ejected can be controlled by adjusting the voltage applied to the piezoelectric actuator.
Control and Precision: The ability to control the voltage applied to the piezoelectric actuator allows for precise control over droplet ejection. By carefully modulating the voltage, the printer can control the amount of ink that is ejected, the droplet size, and the positioning of the droplets on the printing substrate.
High-Resolution Printing: This piezoelectric droplet ejection mechanism is particularly advantageous for high-resolution printing applications, such as pharmaceutical printing, where accurate deposition of small droplets of pharmaceutical liquids onto a substrate (e.g., pills, tablets, or medical devices) is essential.
Overall, the piezoelectric device's ability to rapidly deform and generate pressure changes in the ink chamber enables controlled droplet ejection, allowing for precise pharmaceutical printing with high resolution and accuracy.