US Patent 10546484 Personal safety device

Provided is a personal safety-device configured to be attached to, worn by, or carried by a user, comprising: an audible alarm mechanism configured to be selectively activated; a manually activated actuating member for selectively activating the audible alarm mechanism; and an acoustic chamber defining an acoustic cavity for amplifying the audible alarm; wherein the acoustic chamber is housed in the actuating member, wherein the alarm mechanism and the acoustic cavity are configured to have the same resonant frequency.