Dynamic electroacoustic transducer

Claim 2

A dynamic electroacoustic transducer comprising permanent magnetic means for establishing a plurality of aligned magnetic fields of alternate polarity in parallel thereto, a diaphragm unit including a main diaphragm in the form of a thin flAt film having disposed thereon a flatwise coil, and a pair of opposite auxiliary diaphragms in the form of thin film for carrying said main diaphragm therebetween to maintain the latter flat, and annular holder means of resilient material for clamping the peripheral edge of said diaphragm unit to impart a predetermined stiffness to said main diaphragm, said diaphragm unit being disposed in said aligned magnetic fields so that said flatwise coil intersects perpendicularly said magnetic fields.

Claim 3

A dynamic electroacoustic transducer as claimed in claim 1 wherein each of said auxiliary diaphragms includes a multiplicity of protrusions abutting against the adjacent surface of said main diaphragm.

Claim 4

A dynamic electroacoustic transducer as claimed in claim 1 wherein said annular holder means includes a stretching ring member provided at the inner edge with an annular projecting flange or pushing said diaphragm unit to maintain said main diaphragm in its predetermined tensioned state.

Claim 5

A dynamic electroacoustic transducer as claimed in claim 3, wherein said main diaphragm smaller than said auxiliary diaphragms.

Claim 6

A dynamic electroacoustic transducer comprising, in combination, a pair of opposite discs of permanent magnets disposed in spaced parallel relationship to form a circular gap therebetween, each of said discs of permanent magnet including a plurality of spaced parallel slots, that portion thereof located on either side of each of said slots being magnetized in the direction of thickness of said each disc so that each pair of adjacent magnetized portions are opposite in polarity to each other, a pair of back discs of magnetic material including a plurality of openings and backing said discs of permanent magnet respectively, said slots of each of said discs of permanent magnet overlapping said openings of the adjacent back disc, a main diaphragm in the form of a thin flat film having disposed thereon a flatwise coil, a pair of opposite auxiliary diaphragms in the form of thin film provided on one surface with protrusions to carry said main diaphragm between said protrusions on said opposite auxiliary diaphragms to maintain said main diaphragm flat and annular holder means of resilient material for clamping the peripheral edges of said main and auxiliary diaphragms to impart a predetermined stiffness to said main diaphragm, said main auxiliary diaphragms being disposed in parallel relatioships with said discs of permanent magnet with said flatwise coil perpendicularly intersecting magnetic fields caused from said magnetized portions of said discs of permanent magnet.

Claim 7

A dynamic electroacoustic transducer comprising, in combination, a pair of opposite discs of permanent magnets disposed in spaced parallel relationship to form a circular gap therebetween, each of said discs of permanent magnet including a plurality of spaced parallel slots, that portion thereof located on either side of each of said slots being magnetized in the direction of thickness of said each disc so that each pair of adjacent magnetized portions are opposite in polarity to each other, a pair of back discs of magnetic material including a plurality of openings and backing said discs of permanent magnet respectively, said slots of each of said discs of permanent magnet overlapping said openings of the adjacent back disc, a main diaphragm in the form of a thin flat film having disposed thereon a flatwise coil, a pair of opposite auxiliary diaphragms in the form of thin film provided on one surface with protrusions to carry said main diaphragm between said protrusions on said opposite auxiliary diaphragms to maintain said main diaphragm flat and annular holder means of resilient material for clamping the peripheral edges of said main and auxiliary diaphragms to impart a predetermined stiffness to said main diaphragm, said main auxiliary diaphragms being disposed in parallel relatioships with said discs of permanent magnet with said flatwise coil perpendicularly intersecting magnetic fields caused from said magnetized portions of said discs of permanent magnet.

Claim 8

A dynamic electroacoustic transducer as claimed in claim 5 wherein said openings of each of said backing plates comprises a plurality of parallel slots perpendicularly intersecting said slots of the adjacent disc of permanent magnet.

Claim 9

A dynamic electroacoustic transducer as claimed in claim 4 wherein said openings of each of said back plates comprise a plurality of circular apertures positioned above said slots of the adjacent disc of permanent magnet.

Claim 10

A dynamic electroacoustic transducer comprising, in combination, a pair of opposite discs of permanent magnet disposed in spaced parallel relationship to form a circular gap therebetween, each of said discs of permanent magnet including a plurality of spaced parallel slots, that portion thereof on either side of each of said slots being magnetized in the direction of thickness or said each disc so that each pair of adjacent magnetized portions are opposite in polarity to each other, a pair of slotted back discs of magnetic material backing said discs of permanent magnet respectively, said slots of each of said discs of permanent magnet overlapping said openings of the adjacent back disc, a diaphragm in the form of a thin flat film having disposed thereon flatwise coil, annular holder means having attached thereto the peripheral edge of said diaphragm and a stretching ring member disposed in opposite relationship with said annular holder mEans to tension and diaphragm.

Claim 11

A dynamic electroacoustic transducer comprising, in combination, a pair of opposite discs of permanent magnet disposed in spaced parallel relationship to form a circular gap therebetween, each of said discs of permanent magnet including a plurality of spaced parallel slots, that portion thereof on either side of each of said slots being magnetized in the direction of thickness or said each disc so that each pair of adjacent magnetized portions are opposite in polarity to each other, a pair of slotted back discs of magnetic material backing said discs of permanent magnet respectively, said slots of each of said discs of permanent magnet overlapping said openings of the adjacent back disc, a diaphragm in the form of a thin flat film having disposed thereon flatwise coil, annular holder means having attached thereto the peripheral edge of said diaphragm and a stretching ring member disposed in opposite relationship with said annular holder mEans to tension and diaphragm.