Electro-acoustic transducer and manufacturing process

• US 4,989,254 A
• Filed: 06/30/1989
• Issued: 01/29/1991
• Est. Priority Date: 06/30/1989
• Status: Expired due to Fees

• Current Assignee: Amalaha, Leonard D.
• Original Assignee: Amalaha, Leonard D.
• Inventors: Amalaha, Leonard D.
• Primary Examiner(s): Ng, Jin F.
• Assistant Examiner(s): McGeary, III., M. Nelson
• Application Number:
  US07/373,258
• Time in Patent Office: 578 Days
• Field of Search: 381/202, 381/188, 381/156, 381/158, 381/160, 381/192, 181/155, 181/152
• US Class Current: 381/424
• CPC Class Codes: H04R 1/345 for loudspeakers
• CPC Class Codes: H04R 1/403 loud-speakers
• CPC Class Codes: H04R 31/00 Apparatus or processes specially adapted for the manufacture of transducers or diaphragms therefor manufacture of microstructural arrangements of deformable or non-deformable structures in general B81C1/00182
• CPC Class Codes: H04R 31/006 Interconnection of transducer parts of diaphragm and outer suspension by moulding H04R31/003
• CPC Class Codes: H04R 7/12 Non-planar diaphragms or cones
• CPC Class Codes: H04R 9/025 Magnetic circuit
• CPC Class Codes: H04R 9/063 using a plurality of acoustic drivers H04R1/24 and H04R1/403 take precedence

Abstract

An electro-acoustic transducer having a spherically shaped diaphragm for the generation of sound in an omnidirectional capacity. The spherically shaped diaphragm is constituted of two identical diaphragm halves open at the hemispherical apexes and connected at the equatorial diameter via inwardly extending reinforcing flanges. The spherically shaped unit is driven by magnetic arrangement(s) located within the interior of the spherically shaped diaphragm. The moving coil(s) of the magnetic arrangement(s) are connected to the diaphragm via rigid conical projections from the magnetic arangement(s). The rigid conical projections communicate the movements of the coil(s) to the diaphragm. The diaphragm travels in a north-south direction during operation such that the sound generated will have omnidirectional characteristics with greater pressure in the north-south direction. A wave-guide shaped base plate channels some of the waves from the north-south direction to the east-west direction to increase omnidirectional dispersion of sound. The manufacturing process renders easy assembly of the components of the transducer.

Claims

1. An electro-acoustic transducer which can produce sound in substantially an omnidirectional capacity comprising:

a spherical diaphragm having two oppositely disposed openings;

said spherical diaphragm having upper and lower hemispherical portions, each said hemispherical portion having a peripheral edge flange extending inwardly around the periphery of said hemispherical portion at the equatorial diameter, said hemispherical portions connecting at the equatorial diameter by said inwardly extending peripheral edge flanges;

at least one drive cone disposed within and rigidly connected to said spherical diaphragm over at least one of said openings in said spherical diaphragm;

at least one actuation assembly including a voice coil disposed within said spherical diaphragm, each said at least one actuation assembly connected to each said at least one drive cone, each said actuation assembly also connected to a magnetic assembly, said magnetic assembly having a central gap within which said voice coil is disposed;

spider suspension means connecting each said drive cone to an outer pole piece attached to each said magnetic assembly;

a carrier assembly to which at least one magnetic assembly is attached, said carrier assembly having an outer carrier edge flange;

a resilient circular surround having an outer resilient surround edge flange disposed between and bonded to said inwardly extending peripheral edge flanges of said hemispherical portions, said resilient circular surround having an inner resilient surround edge flange attached to said carrier assembly edge flange;

a support pole disposed through said spherical diaphragm and at least one inner pole piece attached to each said magnetic assembly and supporting said spherical diaphragm, magnetic assembly and said carrier means;

a base plate assembly from which said support pole vertically extends, said base plate disposed beneath said spherical diaphragm and having a concave slope extending radially outward from said support pole, said base plate acting as a wave guide;

whereby

said voice coil, drive cone, magnetic assembly and said actuation assembly serve to drive said spherical diaphragm to produce sound in an omnidirectional manner.

2. An electro-acoustic transducer to produce sound in substantially an omnidirectional capacity according to claim 1 further comprising:

said spherical diaphragm being driven by two drive cones,

said drive cones attaching to opposing polar regions of said spherical diaphragm,

each of said drive cones attaching to one of two actuation assemblies,

two magnetic assemblies located one to each of said hemispherical portions,

said actuation assemblies attaching each to one of said magnetic assemblies,

two voice coils,

two carrier assemblies,

said magnetic assemblies being connected by carrier assemblies wherein the upper of said magnetic assemblies being upright and the lower of said magnetic assemblies being inverted,

said carrier assemblies having carrier edge flanges allowing for the connection of said carrier assemblies to one another,

said carrier edge flange of the lower of said carrier assemblies extending adjacent the equatorial diameter of said spherical diaphragm, and

said resilient surround having an inner resilient surround edge flange attached to said carrier edge flange of the lower of said carrier assemblies.

3. An electro-acoustic transducer to produce sound in substantially an omnidirectional capacity according to claim 1 further comprising:

said spherical diaphragm being driven to produce sound by one drive cone means,

said drive cone attaching to said actuation assembly,

said actuation assembly attaching to said magnetic assembly,

said magnetic assembly housing said voice coil,

said voice coil driving said actuation assembly, and

said inner pole piece having at least one stub wherein said support pole extends through said stub.

4. An electro-acoustic transducer which can produce sound in substantially an omnidirectional capacity according to claim 1, wherein:

said resilient surround is located at the equatorial diameter of said hemispherical portions on the interior of said hemispherical portions.

5. An electro-acoustic transducer to produce sound in substantially omnidirectional capacity according to claim 2, wherein:

said magnetic assemblies are separated from one another allowing for the decrease in size of said drive cones and thereby the increase in the radiative sensitivity of said hemispherical portions.

6. A method of manufacture of an electro-acoustic transducer that can produce sound in substantially an omnidirectional capacity in the low to mid range frequencies comprising a spherical diaphragm means, said spherical diaphragm means dispersing sound generated therefrom in a substantially omnidirectional fashion, said spherical diaphragm means having two hemispherical portions, each of said hemispherical portions having a peripheral edge flange extending inwardly around the periphery of said hemispherical portion at the equatorial diameter, said hemispherical portions connecting at the equatorial diameter by said inwardly extending peripheral edge flanges creating said spherical diaphragm means, said spherical diaphragm means being driven to produce sound by two drive cone means, two actuation assemblies, said drive cone means attaching each to one of said actuation assemblies, two magnetic arrangements, said actuation assemblies attaching each to one of said magnetic arrangements, said drive cone means rigidly connecting to said spherical diaphragm means by a bonding means, at least one voice coil means per one of said actuation assemblies, said voice coil means driving said actuation assembly, said voice coil means being located within an air gap defined by said magnetic arrangement, at least one cup-shaped carrier means connected to each of said magnetic arrangements wherein the upper of said magnetic arrangements being upright and the lower of said magnetic arrangements being inverted, said cup-shaped carrier means having a carrier edge flange, said cup-shaped carrier means having carrier edge flanges allowing for the connection of said cup-shaped carrier means to one another, said carrier edge flange of the lower of said cup-shaped carrier means extending substantially to the equatorial diameter of said spherical diaphragm means, a flexible surround, said flexible surround having an outer flexible surround edge flange sandwiched between and bonded to said inwardly extending peripheral edge flanges of said hemispherical portions, said flexible surround having an inner flexible surround edge flange attached to said carrier edge flange, a support pole attaching to and supporting said magnetic arrangement and said spherical diaphragm means, at least one inner pole piece, said inner pole piece having at least one stub wherein said support pole extends through said stub, a base plate assembly, said support pole extending vertically from a base plate assembly, said base plate assembly having a wave guide shape enhancing the omnidirectional dispersion of sound generated by said spherical diaphragm means, a central tubular projection extending vertically from the center of said base plate, said central tubular projection defining a central cylindrical hole wherein said support pole may be placed and affixed by bonding means, said base plate having reinforcing flanges extending radially between the edge of said base plate and the lower most section of said tubular projection, said voice coil means associating with said magnetic arrangement in such a fashion wherein said voice coil means aid in the upwards vertical motion of said spherical diaphragm means, spider suspension means having two longitudinally disposed ends, said spider suspension means attaching to said drive cone means at one end and to said flexible surround at the other end wherein said spider suspension means functions to move said spherical diaphragm means in a downward vertical direction opposite that generated by said voice coil means, the lower of said hemispherical portions of said spherical diaphragm means having a hemisphere edge flange on said cup-shaped carrier means defining air openings allowing for the free movement of air within said spherical diaphragm means, and said spherical diaphragm means defining polar air openings at the polar regions allowing for the free movement of air within said drive cone means, comprising the following steps of:

lowering said cup-shaped carrier means atop an assembly block wherein the central pin of said assembly block passes through the center of said cup-shaped carrier means,

applying a bonding agent to the top most region of said cup-shaped carrier means,

lowering said magnetic arrangement over said pin of said assembly block wherein said magnetic arrangement sits atop said cup-shaped carrier means thereby bonding said magnetic arrangement to said cup-shaped carrier means,

applying a bonding agent to the upper most surface of said magnetic arrangement,

lowering said actuation assembly over said pin of said assembly block atop said magnetic arrangement thereby bonding said actuation assembly to said magnetic arrangement,

lowering an alignment cap over said pin on said assembly block allowing for the alignment of said hemispherical portion and said actuation assembly as attached to said magnetic arrangement,

bonding said hemispherical portion to said actuation assembly,

removing said alignment cap from said pin,

removing said hemispherical portion containing said actuation assembly, said magnetic arrangement, and said cup-shaped carrier means from said assembly block,

assembling the second of said hemispherical portions in the same manner as the first,

inverting the first of said hemispherical portions, bonding the two of said hemispherical portions together,

mounting and bonding said spherical diaphragm to said tubular projection of said base plate assembly,

positioning and bonding said cap over said polar openings, and

bonding said hemispherical portions to one another by said peripheral edge flanges of said hemispherical portions.

7. A method of manufacture of an electro-acoustic transducer that can produce sound in substantially an omnidirectional capacity in the upper mid to high range frequencies comprising a spherical diaphragm means, said spherical diaphragm means dispersing sound generated therefrom in a substantially omnidirectional fashion, said spherical diaphragm means having two hemispherical portions, each of said hemispherical portions having a peripheral edge flange extending inwardly around the periphery of said hemispherical portion at the equatorial diameter, said hemispherical portions connecting at the equatorial diameter by said inwardly extending peripheral edge flanges creating said spherical diaphragm means, said spherical diaphragm means being driven to produce sound by one drive cone means, one actuation assembly, said drive cone means attaching to said actuation assembly, one magnetic arrangement, said actuation assembly attaching to said magnetic arrangement, said drive cone means rigidly connecting to said spherical diaphragm means by a bonding means, at least one voice coil means per one of said actuation assemblies, said voice coil means driving said actuation assembly, said voice coil means being located within an air gap defined by said magnetic arrangement, a flexible surround, said flexible surround having an outer flexible surround edge flange sandwiched between and bonded to said inwardly extending peripheral edge flanges of said hemispherical portions, said flexible surround having an inner flexible surround edge flange attached to said carrier edge flange, a support pole attaching to and supporting said magnetic arrangement and said spherical diaphragm means, at least one inner pole piece, said inner pole piece having at least one stub wherein said support pole extends through said stub, a base plate assembly, said support pole extending vertically from a base plate assembly, said base plate assembly having a wave guide shape enhancing the omnidirectional dispersion of sound generated by said spherical diaphragm means, a central tubular projection extending vertically from the center of said base plate, said central tubular projection defining a central cylindrical hole wherein said support pole may be placed and affixed by bonding means, said base plate having reinforcing flanges extending radially between the edge of said base plate and the lower most section of said tubular projection, said voice coil means associating with said magnetic arrangement in such a fashion wherein said voice coil means aid in the upwards vertical motion of said spherical diaphragm means, spider suspension means having two longitudinally disposed ends, said spider suspension means attaching to said drive cone means at one end and to said flexible surround at the other end wherein said spider suspension means functions to move said spherical diaphragm means in a downward vertical direction opposite that generated by said voice coil means, the lower of said hemispherical portions of said spherical diaphragm means having a hemisphere edge flange on said cup-shaped carrier means defining air openings allowing for the free movement of air within said spherical diaphragm means, and said spherical diaphragm means defining polar air openings at the polar regions allowing for the free movement of air within said drive cone means, comprising the following steps of:

lowering one of said hemispherical portions in an inverted position over said tubular projection of said base plate assembly,

lowering said magnetic arrangement over and bonding said magnetic arrangement to said tubular projection of said base plate assembly,

applying a bonding agent to the upper most surface of said magnetic arrangement,

lowering said actuation assembly over said pin of said assembly block atop said magnetic arrangement thereby bonding said actuation assembly to said magnetic arrangement,

bonding the upper of said hemispherical portion to said actuation assembly,

bonding the two of said hemispherical portions to one another at said peripheral edge flange.