A piezoelectric gas igniter is a device commonly used to ignite gas-powered appliances like stoves, grills, and water heaters. It relies on the piezoelectric effect to generate a high voltage spark that ignites the gas when it's released into the air. The basic working principle of a piezoelectric gas igniter involves several key components and steps:
Piezoelectric Crystal: At the heart of the igniter is a piezoelectric crystal, usually made of materials like quartz or ceramic. These crystals possess the unique property of generating an electric charge when mechanical stress is applied to them. When you press the button on the igniter, you apply mechanical force to the crystal.
Mechanical Striker: The button or trigger that you press on the igniter is connected to a mechanical striker mechanism. When you press the button, it compresses the piezoelectric crystal, causing it to deform slightly and generate an electric charge. This deformation occurs due to the piezoelectric effect, which converts mechanical energy into electrical energy.
Electric Spark Gap: The generated electric charge needs to be released in the form of a spark to ignite the gas. To achieve this, the electric charge is sent through a spark gap. The spark gap is a small, controlled gap between two conductive surfaces. This gap prevents the electric charge from flowing directly and instead builds up voltage until it's sufficient to create a spark.
Ignition Electrode: One of the conductive surfaces in the spark gap is an ignition electrode. This electrode is positioned close to the gas outlet of the appliance and serves as the point from which the spark is emitted.
Grounding: The other conductive surface is often part of the igniter's housing or structure, providing a ground path for the spark to complete the circuit. The spark travels from the ignition electrode to this grounding point.
Gas Release: Simultaneously with pressing the igniter button, you open the gas valve of the appliance. The gas is released into the air, creating a combustible mixture with oxygen.
Spark Ignition: As the voltage across the spark gap builds up due to the piezoelectric effect, it eventually reaches a critical level. At this point, the electric potential difference is sufficient to ionize the air between the ignition electrode and the grounding point. This ionization forms a conductive path for the electric charge, allowing a spark to jump across the gap.
Gas Ignition: The spark generated in the spark gap ignites the gas mixture in the vicinity of the ignition electrode. The ignited gas creates a flame, providing the necessary heat for the gas-powered appliance to start functioning.
The piezoelectric gas igniter's working principle relies on the conversion of mechanical pressure into an electric charge, which is then transformed into a spark to ignite the gas. It's a reliable and convenient method for igniting gas appliances without the need for external power sources or open flames.