Charles Lloyd Daugherty

US Patent:

20040083876, May 6, 2004

Filed:

Apr 1, 2003

Appl. No.:

10/404461

Inventors:

Jack Maegli - Beloit WI, US
Charles Daugherty - Ridgecrest CA, US

International Classification:

G10D013/08

US Classification:

084/410000

Abstract:

The objective of the embodiment is to maximize amplitude sustentation of the primary (or fundamental) frequency of metal wind chime tubes, while at the same time attenuating undesirable harmonic frequencies. This is accomplished by designing the dimensions of each tube of the chime such that they are in resonance with the standing air wave inside the tube. To achieve maximum resonance it has been observed that there is maximum amplitude sustentation with time when the tube dimensions are such that the length of the tube approximates the second natural air column wave length. At this length equivalency there is a wave node match between the second natural frequency of the air column inside the tube and that of the primary natural frequency wave of the tube. The constructive interference thus accomplished supports the primary frequency of the tube and by such attenuates expression of harmonic frequencies. The tubular dimension requisite to establish said wave length match expressed by length to diameter ratio (L/D) defines what the author's term an “ideal tube”.