| 摘要 |
Provided is a personal safetydevice 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 intheactuating member, wherein the alarm mechanism and the acoustic cavityare configured to have the same resonant frequency. |
