Patent ID: 7793607
Filing Date: 2010-09-14
Classification: G08B

Abstract:
1. A civil defense tone generator, comprising; (a) a compressed air tank, (b) an air compressor and a prime mover for powering the air compressor, (c) a pressure switch set at a pre-selected lower limit pressure in communication with the compressor and at least indirectly with the compressed air tank, the pressure switch adapted to activate the air compressor when the pressure in the air receiver tank and the compressed air tank is below the pre-selected lower limit pressure, (d) a tone generator which receives a flow of compressed air and generates a tone, the tone generator having a lower chamber including an inlet for receiving the flow of compressed air, an upper chamber having at least one opening defined in its outside wall and at least one channel in communication with the lower chamber and extending past the at least one opening in the upper chamber, the channel bounded by an outside wall including a whistle plate having a sharp edged blade element positioned proximate to the at least one opening in the upper chamber so that air passing through the channel will vibrate to produce a tone, (e) an air supply line pneumatically communicating at least indirectly between the air storage tank and the tone generator, (f) a control valve in the air supply line, the control valve movable between an open position and a closed position for opening and closing pneumatic communication through the air supply line, the control valve adapted to deliver air to the tone generator at a pressure that is substantially lower than the pre-selected lower limit pressure of the compressed air tank, (g) a controller including a remote signal receiver, the controller connected to the control valve and adapted for changing the position of the control valve between the closed position wherein no tone is generated and the open position wherein a tone is generated in response to a signal from a remote location.