Electrical audio signal processing systems and devices – Electro-acoustic audio transducer – Driven diverse static structure
Reexamination Certificate
1999-07-27
2001-04-10
Kuntz, Curtis A. (Department: 2743)
Electrical audio signal processing systems and devices
Electro-acoustic audio transducer
Driven diverse static structure
C381S426000, C181S167000
Reexamination Certificate
active
06215881
ABSTRACT:
DESCRIPTION
1. Technical Field
The invention relates to loudspeakers and more particularly to loudspeakers comprising panel-form acoustic radiating elements.
2. Background Art
It is known from GB-A-2262861 to suggest a panel-form loudspeaker comprising:
resonant multi-mode radiator element being a unitary sandwich panel formed of two skins of material with a spacing core of transverse cellular construction, wherein the panel is such as to have ratio of bending stiffness (B), in all orientations, to the cube power of panel mass per unit surface area (&mgr;) of at least 10;
a mounting means which supports the panel or attaches to it a supporting body, in a free undamped manner;
and an electro-mechanical drive means coupled to the panel which serves to excite a multi-modal resonance in the radiator panel in response to an electrical input within a working frequency band for the loudspeaker.
There is a wide application for sound distribution using speakers in standard module form, interchangeable with commercial ceiling tiles, generally on a 600×600 mm format, the objective being the even distribution of articulate speech and music over a large area. Some conventional moving coil drivers and panel derivatives are presently made for this application.
Existing technology uses cone type moving coil speakers fitted into frames and acoustic baffles. While commonly used due to moderate cost and ready availability, these suffer from serious hot spot (excessive sound intensity) and directional effects and consequently poorer intelligibility off axis. Many units are required to give a uniform coverage over larger area.
Another known development uses a cone type speaker where the ‘cone’ is a polystyrene structure with a flat front surface, which may be painted. Here a combination of additional moving coil drivers fitted to their diaphragm, the latter structured to shrink acoustically with increasing frequency, may give a wider radiation pattern than a conventional cone speaker. These polystyrene foam speaker units require chassis and acoustic baffles for mounting them in position.
DISCLOSURE OF INVENTION
Embodiments of the present invention use members of nature, structure and configuration achievable generally and/or specifically by implementing teachings of our patent application Ser. No. 08/707,012. Such members thus have capability to sustain and propagate input vibrational energy by bending waves in operative area(s) extending transversely of thickness often but not necessarily to edges of the member(s); are configured with or without anisotropy of bending stiffness to have resonant mode vibration components distributed over said area(s) beneficially for acoustic coupling with ambient air; and have predetermined preferential locations or sites within said area for transducer means, particularly operationally active or moving part(s) thereof effective in relation to acoustic vibrational activity in said area(s) and signals, usually electrical, corresponding to acoustic content of such vibrational activity. Uses are envisaged in U.S. Pat. application No. 08/707,012 for such members as or in “passive” acoustic devices without transducer means, such as for reverberation or for acoustic filtering or for acoustically “voicing” a space or room; and as or in “active” acoustic devices with transducer means, such as in a remarkably wide range of sources of sound or loudspeakers when supplied with input signals to be converted to said sound, or in such as microphones when exposed to sound to be converted into other signals.
This invention is particularly concerned with active acoustic devices in the form of loudspeakers the purpose of use in a suspended ceiling tile.
Members as above are herein called distributed mode radiators and are intended to be characterised as in the said parent application and/or otherwise as specifically provided herein.
The invention is a ceiling tile for a ceiling and incorporating a loudspeaker, characterised in that the tile is in the form of a distributed mode acoustic radiator, and by a transducer mounted wholly and exclusively on the radiator to vibrate the radiator to cause it to resonate. A resilient suspension may be disposed at the periphery of the radiator and by which the radiator is supported in the suspended ceiling.
The radiator may be a stiff lightweight panel comprising a cellular core sandwiched by high modulus skins.
REFERENCES:
patent: 3247925 (1966-04-01), Warnaka
patent: 3347335 (1967-10-01), Watters et al.
patent: 3509290 (1970-04-01), Mochida et al.
patent: 3553392 (1971-01-01), Liebscher
patent: 3570626 (1971-03-01), Mochida et al.
patent: 3597962 (1971-08-01), Holtz
patent: 3686927 (1972-08-01), Scharton
patent: 4198550 (1980-04-01), Matsuda et al.
patent: 4300655 (1981-11-01), Sakamoto et al.
patent: 4392027 (1983-07-01), Bock
patent: 4426556 (1984-01-01), Saiki et al.
patent: 4506117 (1985-03-01), Fresard
patent: 4829581 (1989-05-01), Nieuwendijk et al.
patent: 4899390 (1990-02-01), Takewa et al.
patent: 5025474 (1991-06-01), Tanaka et al.
patent: 5073946 (1991-12-01), Satoh et al.
patent: 5425107 (1995-06-01), Bertagni et al.
patent: 6058196 (2000-05-01), Heron
patent: 6097829 (2000-07-01), Guenther et al.
patent: WO 95/14296 (1995-05-01), None
Azima Henry
Colloms Martin
Harris Neil John
Dabney P.
Foley & Lardner
Kuntz Curtis A.
New Transducers Limited
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