Patent · US Expired

Emergency whistle

US5546887A · kind A · utility

17Cited by
4References
13Claims
0Family size

Inventor

Key dates

Filing dateApr 7, 1994
Grant dateAug 20, 1996
Priority date
Expiry dateApr 7, 2014

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG10K5/00
  • WIPO fieldOther consumer goods
  • WIPO sectorOther fields

Abstract

An emergency signalling whistle which simultaneously emits high- and low-pitched whistle tones so as to be detectable from relatively long distances and localizable from relatively short distances. A mouthpiece contains first and second air passages which discharge across openings into chambers of different sizes. The whistle also incorporates cylindrically concave grip surfaces which align with the ends of the person's thumb and forefinger in the grip position. In addition, there is an enlarged flange at the end of the mouthpiece which is retained in the person's mouth by the incisor teeth, and a second flange around the mouthpiece which forms a seal against the outer surface of the person's lips.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.