Selectively tuned vibration absorber
OwnerLeonard N. Thomaseninventor
Life of this patent
Estimating the term…
Abstract
A selectively tuned vibration absorber comprising a stack of viscoelastic polymer damping plates, secured together with spacers at both ends and having metal tuning weights attached onto the topmost plate in the stack. The apparatus is secured to the low frequency drive unit of an in-wall loudspeaker with a metal mounting plate between the vibration absorber and the low frequency drive unit. Both ends of the vibration absorber are cantilevered over a tuning mounting plate centered between the ends of the unit, the degree of cantilever and the mass in the metal weights added to the topmost damping plate being variable such that the vibration absorber may be tuned to resonate at the fundamental resonance frequency of the low frequency drive unit.
Claims20
A vibration attenuating apparatus for reducing baffle vibrations and sound distortion in an in-wall loudspeaker, comprising:
- a connection plate for connecting said apparatus to an in-wall loudspeaker;
- connection means for attaching said connection plate to the backplate of the in-wall loudspeaker;
- a plurality of vibration damping plates arranged in a stacked and spaced-apart configuration, said vibration damping plates comprising a tuning compliance plate, a top plate, and at least one intermediate vibration damping plate interposed between said tuning compliance plate and said top plate, all of said damping plates having outer ends;
- a tuning mounting plate interposed between said tuning compliance plate and said connection plate and positioned such that said tuning compliance plate is cantilevered over said tuning mounting plate;
- a plurality of damping pads interposed between said connection plate and said tuning compliance plate;
- a plurality of spacers interposed between said vibration damping plates and disposed at each of said ends of said intermediate vibration damping plates for securing said damping plates one to another at their respective ends;
- at least one tuning plate affixed to said top plate on the side opposite said at least one intermediate vibration damping plate;
- and
- attachment means for affixing said at least one tuning plate to said top plate.
A vibration attenuating apparatus for reducing undesirable vibrations in a low frequency drive unit of an in-wall loudspeaker having a backplate, comprising:
- a connection plate for connecting said apparatus to the loudspeaker backplate;
- connection means for attaching said connection plate to the loudspeaker backplate;
- a top plate;
- a tuning compliance plate;
- a plurality of intermediate vibration damping plates, all of a substantially rectangular shape, having the same size as one another and substantially the same size as said top plate and said tuning compliance plate, and arranged in a parallel, stacked and spaced-apart configuration, interposed between and spaced apart from said tuning compliance plate and said top plate;
- a tuning mounting plate interposed between said tuning compliance plate and said connection plate such that said tuning compliance plate, said plurality of intermediate vibration damping plates, and said top plate are all cantilevered over said tuning mounting plate;
- first through fourth damping pads interposed between the corners of said connection plate and said tuning compliance plate;
- a plurality of spacers interposed between said vibration damping plates and disposed at each of said ends of said intermediate vibration damping plates for securing said damping plates one to another their respective ends, said spacers having a thickness of 0.093 inch, a width of ⅛ inch, and a length equal to the width of said intermediate vibration damping plates, said top plate, and said tuning compliance plate;
- a first and second tuning plate affixed to said top plate on the side opposite said at least one intermediate vibration damping plate;
- and
- attachment means for affixing said first and second tuning plates to said top plate.
Dependencies are inferred from the claim text.