US Patent 10350948 Filling device for an inflatable unit

The invention provides a filling device for an inflatable unit, e.g., a pneumatic tire for a car. The device is connectable to a source of air pressure and to a valve for the inflatable unit. The valve has a whistle arranged to produce an audible signal based on a flow of air in the release outlet, and to enable improved handling and sound performance, the whistle comprises a flow-path forming a first leg extending radially from the passage, and a second leg extending about the passage.