EP 0239914 A3 19901010 - AN ELECTRONIC LOUDSPEAKER SYSTEM HAVING A HARMONIOUS SOUND WITH MULTIPLE ADJUSTABLE SOUND LEVELS
Title (en)
AN ELECTRONIC LOUDSPEAKER SYSTEM HAVING A HARMONIOUS SOUND WITH MULTIPLE ADJUSTABLE SOUND LEVELS
Publication
Application
Priority
CN 86201730 U 19860325
Abstract (en)
[origin: EP0239914A2] An electronic loudspeaker which comprises a characteristic wave shape generator (1), an attenuator (2), an amplifier (3), a loudspeaker (4) and a controller (5), is designed on the basis of the principle of harmony and acoustics; the loudspeaker according to the invention has multiple and adjustable sound levels; it can give out alarming at multiple adjustable sound levels and give instructions in an analogous human voice when a vehicle is turning a corner, or moving backward, it also can be used as a microphone for public addressing. Because of its multifunction, low voice pollution, and a long service life, it is suitable for various transport means for a safe driving, and it also can be used for alarming purpose in other cases.
IPC 1-7
IPC 8 full level
G08B 3/10 (2006.01); H04R 3/00 (2006.01); H04R 27/00 (2006.01)
CPC (source: EP)
G08B 3/10 (2013.01)
Citation (search report)
- US 4290053 A 19810915 - NEMOTO KUNIICHI
- US 4437088 A 19840313 - FERGUSON HARRY D [CA]
- US 4183278 A 19800115 - REA IRVIN B [US], et al
- US 4284845 A 19810818 - BELCHER CLAUDE A
- DE 2554940 A1
Designated contracting state (EPC)
DE FR GB IT
DOCDB simple family (publication)
EP 0239914 A2 19871007; EP 0239914 A3 19901010; BR 8701340 A 19871229; CN 86201730 U 19870121; JP S62272700 A 19871126
DOCDB simple family (application)
EP 87104319 A 19870324; BR 8701340 A 19870324; CN 86201730 U 19860325; JP 6926187 A 19870325