Micro-speaker having an air adsorbent
The present invention relates to a micro-speaker for use in a small electronic device, and more particularly, to a micro-speaker having an enclosure applied thereto and having an air adsorbent which can improve the low frequency sound quality. According to the present invention, it is possible to provide a micro-speaker which shows excellent improvement in the low frequency characteristics, regardless of a mass ratio of silicon to aluminum of an air adsorbent, and also possible to provide a micro-speaker which shows excellent improvement in the low frequency characteristics at a low cost, by reducing a mass ratio of silicon to aluminum, as compared with the conventional micro-speaker having an air adsorbent.
1. A micro-speaker, comprising:
an enclosure;
a speaker unit accommodated in the enclosure;
a resonance space defined between the enclosure and the speaker unit; and
an air adsorbent provided in the resonance space,
wherein the air adsorbent is zeolite having at least 40% of channels with a size of 0.4 nm to 0.6 nm,
wherein the zeolite is provided in the form of granules with a grain size of 0.2 mm to 0.5 mm.
2. The micro-speaker of claim 1 , wherein the zeolite is selected from the group consisting of FER, MFI, MEL, TON, and MFS.
3. The micro-speaker of claim 1 , wherein the zeolite has a specific surface area BET of at least 400 m 2 /g.
4. The micro-speaker of claim 1 , wherein inner micropores of the zeolite have a volume of 0.25 cm 3 /g to 0.35 cm 3 /g per unit mass.
5. The micro-speaker of claim 1 , wherein the air adsorbent is arranged in a specific portion of the resonance space.
6. The micro-speaker of claim 5 , wherein the air adsorbent comprises two or more air adsorbent arrangement portions provided around the speaker unit.
7. The micro-speaker of claim 5 , wherein the air adsorbent surrounds the speaker unit in a non-continuous manner.