Micro-gas pressure driving apparatus

The present invention relates to a piezoelectric actuator which is small and quiet. The piezoelectric actuator comprises a suspension plate, a piezoelectric ceramic plate, an outer frame, and a bracket. The suspension plate is allowed to receive vibration with many curves from a middle portion to a surrounding portion. The piezoelectric ceramic plate is attached onto the suspension plate. When a voltage is applied to the piezoelectric ceramic plate, the suspension plate is driven to receive vibration with many curves. The outer frame is arranged around the suspension plate. The bracket is connected between the suspension plate and the outer frame to elastically support the suspension plate, and includes a middle portion formed in an empty space between the suspension plate and the outer frame to be parallel with the outer frame and the suspension plate, a first connection portion arranged between the middle portion and the suspension plate, and a second connection portion arranged between the middle portion a