EP0065808A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Ribbon-type electro-acoustic transducer with low distortion and improved sensitivity
Assignee: Koninklijke Philips NV
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Filing: 1982-05-21
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Granted: —
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Expires: 2002-05-21
Abstract
Abstract A ribbon-type electro-acoustic transducer has a magnet system which comprises an upper plate (2, 3) and a centre pole (1) between which an air gap (8) is formed. A diaphragm (7) on which conductors (9) are arranged, is disposed in the air gap. The upper plate (2, 3) comprises two plate-shaped parts (2', 3' and 2", 3" respectively) between which a space (11) is formed in which an edge portion of the diaphragm is located. This results in a more homogeneous magnetic field, so that the transducer distortion may be reduced. Moreover, the transducer sensitivity is improved and is suitable for handling signals in the mid-range audio frequency spectrum. The cavity (15) enclosed by the magnet system and the diaphragm (7) can be acoustically coupled, as the case may be via an additional cavity, to a (bass-reflex) duct or an additional (passive radiator) diaphragm.
Inventors
- 👤 Joris Adelbert Maria Nieuwendijk
- 👤 Wilhelmus Dominicus Antonius Maria Van Gijssel
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 15:47
CPC Classifications
H; H04; H04R; H04R9/00; H04R9/02; H04R9/04; H04R9/046; H04R9/047
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
102 words
An electro-acoustic transducer which comprises a magnet system, which system comprises an upper plate and a centre poles between which at least one air gap is formed, and a diaphragm disposed in the air gap, on which diaphragm at least one conductor is arranged, characterized in that the upper plate comprises two plate-shaped parts, which parts have major surfaces which face each other and extend parallel to the plane of the diaphragm and are situated at least substantially in the plane of the diaphragm, portions of the facing major surfaces bounding a space in which an edge portion of the:diaphragm is located.
Claim 2
Dependent Claim
102 words
An electro-acoustic transducer which comprises a magnet system, which system comprises an upper plate and a centre poles between which at least one air gap is formed, and a diaphragm disposed in the air gap, on which diaphragm at least one conductor is arranged, characterized in that the upper plate comprises two plate-shaped parts, which parts have major surfaces which face each other and extend parallel to the plane of the diaphragm and are situated at least substantially in the plane of the diaphragm, portions of the facing major surfaces bounding a space in which an edge portion of the:diaphragm is located.
Claim 3
Dependent Claim
33 words
An electro-acoustic transducer as claimed in Claim 1, characterized in that the centre pole extends to a location nearest the diaphragm surface, the diaphragm portion situated nearest the centre pole being freely movable.
Claim 4
Dependent Claim
48 words
An electro-acoustic transducer as claimed in Claim 1 or 2, characterized in that the centre pole comprises two parts which extend one on each side of the plane of the diaphragm, the part of the diaphragm disposed between the two parts of the centre pole being freely movable.
Claim 5
Dependent Claim
69 words
An electro-acoustic transducer as claimed in Claim 3, characterized in that the parts of the centre pole and the upper plate disposed on one side of the plane of the diaphragm are shaped in such a way that the end surfaces of these parts which face the air gap diverge in a direction perpendicular to and away from the diaphragm surface, so that a horn-like radiation port is obtained.
Claim 6
Dependent Claim
37 words
An electro-acoustic transducer as claimed in any of the preceding Claims, characterized in that the diaphragm has a rectangular shape and is curved in a direction corresponding to the direction of the conductor(s) in an air gap.
Claim 7
Dependent Claim
68 words
An electro-acoustic transducer as claimed in any one of the preceding Claims, characterized in that the magnet system and the diaphragm enclose a cavity which is acoustically coupled, as the case may be via an additional cavity, to a duct, the dimensions of the duct being tuned to the volume of the cavity (cavities) in such a way that the low frequency behaviour of the transducer is improved.
Claim 8
Dependent Claim
84 words
An electro-acoustic transducer as claimed in any of the Claims 1 to 5, characterized in that the magnet system and the diaphragm enclose a cavity which is acoustically coupled, as the case may be via an additional cavity, to an additional diaphragm which is inserted in an opening in the said cavity (cavities), the diaphragm, as to its mass and tension, being tuned to the volume of the cavity (cavities) in such a way that the low frequency behaviour of the transducer is improved.
Claim 9
Dependent Claim
101 words
An electro-acoustic transducer which comprises a magnet system, which magnet system comprises an upper plate and a centre pole between which at least one air gap is formed, and a diaphragm disposed in the air gap, on which diaphragm at least one conductor is arranged, characterized in that the magnet system and the diaphragm enclose a cavity which is acoustically coupled, as the case may be via an additional cavity, to a duct, the dimensions of the duct being tuned to the volume of the cacity (cavities) in such a way that the low frequency behaviour of the transducer is improved.
Claim 10
Dependent Claim
101 words
An electro-acoustic transducer which comprises a magnet system, which magnet system comprises an upper plate and a centre pole between which at least one air gap is formed, and a diaphragm disposed in the air gap, on which diaphragm at least one conductor is arranged, characterized in that the magnet system and the diaphragm enclose a cavity which is acoustically coupled, as the case may be via an additional cavity, to a duct, the dimensions of the duct being tuned to the volume of the cacity (cavities) in such a way that the low frequency behaviour of the transducer is improved.
Claim 11
Dependent Claim
99 words
An electro-acoustic transducer which comprises a magnet system, which magnet system comprises an upper plate and a centre pole between which at least one air gap is formed, and a diaphragm disposed in the air gap, on which diaphragm at least one conductor is arranged, i characterized in that the magnet system and the diaphragm enclose a cavity which is acoustically coupled, as the case may be via an additional cavity, to an additional diaphragm which is inserted in an opening in said cavity (cavities) in such a way that the low frequency behaviour of the transducer is improved.
Claim 12
Dependent Claim
99 words
An electro-acoustic transducer which comprises a magnet system, which magnet system comprises an upper plate and a centre pole between which at least one air gap is formed, and a diaphragm disposed in the air gap, on which diaphragm at least one conductor is arranged, i characterized in that the magnet system and the diaphragm enclose a cavity which is acoustically coupled, as the case may be via an additional cavity, to an additional diaphragm which is inserted in an opening in said cavity (cavities) in such a way that the low frequency behaviour of the transducer is improved.
References Cited (Backward Citations)
No citation records indexed.
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