US3748727A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making electret transducers
Assignee: Individual
•
Filing: 1968-07-11
•
Granted: 1973-07-31
•
Expires: 1988-07-11
Abstract
Abstract Dielectric material is polarized or electrified so as to form an electret which is suited for use in a microphone or other transducer by the method which includes the steps of forming an intimate contact between the dielectric material and a conductor material and then separating these when the dielectric is cool, preferably while maintaining an electrical connection between conductors on the two surfaces of the dielectric during the separation step, without the employment of an external electric field.
Inventors
- 👤 W Swain
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:14
CPC Classifications
H; H01; H01G; H01G7/00; H01G7/02; H01G7/021; H01G7/023; H01G7/025; H04; H04R; H04R19/00; H04R19/01; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49005
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
133 words
The method of polarizing a dielectric to form an electret, which includes the placing of a sheet of dielectric material of such thickness as to be readily vibratable between relatively thin metallic sheets of such thickness as will permit them to be readily peeled from an attached surface, connecting said metallic sheets in electrical connection, applying pressure and heat to said dielectric and metallic sheets in amounts of heat and degree of pressure regulated in accordance with the known properties of the dielectric material and the metallic material to provide an intimate bond between these materials sufficient to initiate the creation of electric voltage in the dielectric, allowing the sheets to cool and peeling said metallic sheets from said dielectric sheet to prevent frictional sliding motion between the said dielectric and metallic surfaces.
Claim 2
Independent Claim
133 words
The method of polarizing a dielectric to form an electret, which includes the placing of a sheet of dielectric material of such thickness as to be readily vibratable between relatively thin metallic sheets of such thickness as will permit them to be readily peeled from an attached surface, connecting said metallic sheets in electrical connection, applying pressure and heat to said dielectric and metallic sheets in amounts of heat and degree of pressure regulated in accordance with the known properties of the dielectric material and the metallic material to provide an intimate bond between these materials sufficient to initiate the creation of electric voltage in the dielectric, allowing the sheets to cool and peeling said metallic sheets from said dielectric sheet to prevent frictional sliding motion between the said dielectric and metallic surfaces.
Claim 3
Dependent Claim
37 words
The method of polarizing a dielectric to form an electret as claimed in claim 1, wherein the dielectric material is a readily vibratable sheet of polyethylene and the material is aluminum foil of the normal market thickness.
Claim 4
Dependent Claim
40 words
The method of polarizing a dielectric to form an electret as claimed in claim 1, wherein the dielectric material is a readily vibratable sheet of isinglass and the metallic material is aluminum foil in sheet form of normal market thickness.
Claim 5
Dependent Claim
44 words
The method of polarizing a dielectric to form an electret as claimed in claim 1, which includes the placing of a readily polarized adhesive material between the sheets of dielectric and metallic material to enhance the physical bonding of the material of the sheets.
Claim 6
Dependent Claim
117 words
The method of polarizing a dielectric as claimed in claim 1, wherein the step of separating consists of peeling part of a first selected said metallic material from the associated said surface of said dielectric material in such manner as to prevent frictional sliding motion between the dielectric and metallic material while maintaining electrical connection between said first selected metallic material and said metallic material on the opposite side surface of said dielectric material, then peeling part of said metallic material from said opposite surface while still maintaining said electrical contact, and continuing in this fashion until a digital pattern of a desired form has been produced in the said surface of said dielectric material. the dielectric
Claim 7
Independent Claim
156 words
The method of polarizing a dielectric to form an electret which comprises placing two sheets of dissimilar materials, one of which is a dielectric material in sheet form of such thickness as to be readily vibratable, and the other relatively thin sheet of a metallic material of such thickness as to permit it to be peeled from thedielectric material in a lifting metal sheet distorting action, placing said sheets in flatwise contact with each other, applying heat and pressure of degrees determined by the known determined composition of the dielectric and metallic materials necessary to form a physical bond between said sheets of material to cause an interchange of electron orbits in the atoms and molecules of the dissimilar materials, allowing the sheets of material to cool and then separating the materials by peeling one from the other in such manner as to prevent creation of friction between the sheets of material during the separating operation.
Claim 8
Independent Claim
156 words
The method of polarizing a dielectric to form an electret which comprises placing two sheets of dissimilar materials, one of which is a dielectric material in sheet form of such thickness as to be readily vibratable, and the other relatively thin sheet of a metallic material of such thickness as to permit it to be peeled from thedielectric material in a lifting metal sheet distorting action, placing said sheets in flatwise contact with each other, applying heat and pressure of degrees determined by the known determined composition of the dielectric and metallic materials necessary to form a physical bond between said sheets of material to cause an interchange of electron orbits in the atoms and molecules of the dissimilar materials, allowing the sheets of material to cool and then separating the materials by peeling one from the other in such manner as to prevent creation of friction between the sheets of material during the separating operation.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-30 | 1977-01-29 | 1977-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-30 | 1981-01-29 | 1981-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-30 | 1985-01-29 | 1985-07-31 | $7700.00 | Window Closed / Lapsed |