US2009520A - Electroacoustic device - Google Patents
Electroacoustic device Download PDFInfo
- Publication number
- US2009520A US2009520A US707190A US70719034A US2009520A US 2009520 A US2009520 A US 2009520A US 707190 A US707190 A US 707190A US 70719034 A US70719034 A US 70719034A US 2009520 A US2009520 A US 2009520A
- Authority
- US
- United States
- Prior art keywords
- microphone
- electrode
- amplifier
- condenser type
- diaphragm
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 8
- 239000011248 coating agent Substances 0.000 description 6
- 238000000576 coating method Methods 0.000 description 6
- 229920002160 Celluloid Polymers 0.000 description 4
- 235000011187 glycerol Nutrition 0.000 description 4
- 239000004020 conductor Substances 0.000 description 3
- 239000012530 fluid Substances 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 238000004804 winding Methods 0.000 description 3
- 239000005030 aluminium foil Substances 0.000 description 2
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 2
- 230000002745 absorbent Effects 0.000 description 1
- 239000002250 absorbent Substances 0.000 description 1
- 239000004411 aluminium Substances 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000011888 foil Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R19/00—Electrostatic transducers
- H04R19/02—Loudspeakers
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R19/00—Electrostatic transducers
- H04R19/04—Microphones
Definitions
- ⁇ condenser type for example, is increased to such an extent that the electric connection with the associated amplifying apparatus can be effected "without taking into consideration the length of the' conductors between the microphone and the amplifier.
- the invention may also be applied advantageously to sound reproducers of the condenser type.
- a dielectric comprising a fluid having a high dielectric constant.
- the fluid is preferably absorbed in a suitable medium or vehicle, for example, of paper or the like. If the microphone 'or reproducer comprises an arrangement in which the diaphragm engages or rests upon a perforated stationary metal electrode, as in the construction shown in,
- FIG. 1 is a. fragmentary view in cross section of a microphone or reproducer of the condenser type embodying the invention.
- Figs. 2 and 3 are circuit diagrams illustrating applications of the invention.
- the invention is embodied in the diaphragm of a microphone, telephone receiver or loudspeaker of the condenser type.
- the diaphragm comprises an extremely thin coating I of collodion, celluloid or the like on a disc or sheet 2 of paper or the like impregnated with a fluid of high dielectric constant, the disc or sheet 2 having an extremely thin conducting covering or coating 3, preferably of metal foil.
- the disc 2 may be impregnated with a liquid, such as Water Aor glycerin, the dielectric constants of which are 80 and 40 times greater than air, respectively.
- the layer 3 may consist, for example, of aluminium or gold foil.
- The' purpose of the coating I is to prevent the moist paper from adhering to the perforated metal electrode 4.
- the outer coating I is strongly damped by the paper di'sc 2 so that it is unnecessary to damp the air vibrations in the passages in theelectrode 4 to a great extent; that is, the lower ends of the passages need not be completely closed. It has been demonstrated in actual practice that, by constructing the diaphragm as described above, the electrostatic capacity may be increased 10G-fold as compared with prior apparatus of the same size.
- Fig. 2 is shown,.by way of example, a circuit in which a microphone 5 embodying the invention is connected to an amplifier.
- the terminals of the microphone 5 are connected to an auto-transformer 6 having a condenser 'l connected between the windings thereof.
- the transformer 6 is connected to the amplifier by conductors 8 through which current is supplied to the microphone'from a battery 9.
- Resistors I 0 of high ohmic resistance are connected to the terminals of the battery 9 and in series relation with the primary windings of an'input transformer I I of the amplifier, the secondary windingof the input transformer being connected to an amplifier tube I2 in the usual manner.
- a condenser I1 is connected between the primary windings of a the transformer II in shunt relation with the battery 9.
- a microphone constructed in accordance with the invention is particularly suitable for use in 4a system of this kind because its high electrostatic capacity minimizes the ⁇ effect of variations in the length of the conductors 8 between the microphone and the amplifier.
- the invention is also of value in systems where the improved apparatus is used as a telephone receiver or loudspeaker.
- Such a system is illustrated in Fig. 3 where the reproducer I3 is energized through the anode resistance I4 from a battery I5 and is connected in the output circuit of the iinal amplifier tube I6 of a conventional amplifier.
- the microphone or telephone need not be directly connected with the associated amplifier as the great capacity thereof makes it possible to use a transformer which permits the impedance of the microphone or telephone to be transformed to any desired value.
- An acoustic device of the condenser type comprising a stationary elctrode and a dia- 50 phragm having a conducting aluminium foil, an Aabsorbent layer impregnated with glycerine, and
- An acoustic device of the condenser type comprising a stationary electrode and a diaphragm having a conducting gold foil, an absorbent layer impregnated with glycerine, and a layer of oelluloid adjacent the electrode.
- An acoustic device of the condenser type comprising a stationary. electrode and a dia--v phragm having a conducting aluminium foil, an absorbentl layer impregnated -with glycerine, and a layer of collodion adjacent the electrode.
- An acoustic device of the condenser type comprising a stationary electrode having openings therein, a conducting diaphragm overlying said electrode and a exible sheet interposed being a coating of -celluloid on the side in contact 10 with said stationary electrode.
Description
Patented July 30, 1935 UNITED sTATEs PATENT OFFICE Application January 18, 1934, Serial No. 707,190
In Germany June 29, 1933 f Claims.
` condenser type, for example, is increased to such an extent that the electric connection with the associated amplifying apparatus can be effected "without taking into consideration the length of the' conductors between the microphone and the amplifier. The invention may also be applied advantageously to sound reproducers of the condenser type.
, In apparatus of the character described, according to the invention, a dielectric is employed comprising a fluid having a high dielectric constant. The fluid is preferably absorbed in a suitable medium or vehicle, for example, of paper or the like. If the microphone 'or reproducer comprises an arrangement in which the diaphragm engages or rests upon a perforated stationary metal electrode, as in the construction shown in,
my German Patent No. 455,151 or U. S. Patent No. 1,859,170, a thin coating of collodion, celluloid or the like is preferably provided to Aprevent the vehicle from adhering to the electrode.A
For a better understanding of the invention, reference should be had to the accompanying drawing, wherein Fig. 1 is a. fragmentary view in cross section of a microphone or reproducer of the condenser type embodying the invention; and
Figs. 2 and 3 are circuit diagrams illustrating applications of the invention.
As shown in Fig, 1, the invention is embodied in the diaphragm of a microphone, telephone receiver or loudspeaker of the condenser type. The diaphragm comprises an extremely thin coating I of collodion, celluloid or the like on a disc or sheet 2 of paper or the like impregnated with a fluid of high dielectric constant, the disc or sheet 2 having an extremely thin conducting covering or coating 3, preferably of metal foil. The disc 2 may be impregnated with a liquid, such as Water Aor glycerin, the dielectric constants of which are 80 and 40 times greater than air, respectively. The layer 3 may consist, for example, of aluminium or gold foil.
The' purpose of the coating I is to prevent the moist paper from adhering to the perforated metal electrode 4. On the other hand, the outer coating I is strongly damped by the paper di'sc 2 so that it is unnecessary to damp the air vibrations in the passages in theelectrode 4 to a great extent; that is, the lower ends of the passages need not be completely closed. It has been demonstrated in actual practice that, by constructing the diaphragm as described above, the electrostatic capacity may be increased 10G-fold as compared with prior apparatus of the same size.
In Fig. 2 is shown,.by way of example, a circuit in which a microphone 5 embodying the invention is connected to an amplifier. AThe terminals of the microphone 5 are connected to an auto-transformer 6 having a condenser 'l connected between the windings thereof. The transformer 6 is connected to the amplifier by conductors 8 through which current is supplied to the microphone'from a battery 9. Resistors I 0 of high ohmic resistance are connected to the terminals of the battery 9 and in series relation with the primary windings of an'input transformer I I of the amplifier, the secondary windingof the input transformer being connected to an amplifier tube I2 in the usual manner. A condenser I1 is connected between the primary windings of a the transformer II in shunt relation with the battery 9. A microphone constructed in accordance with the invention is particularly suitable for use in 4a system of this kind because its high electrostatic capacity minimizes the `effect of variations in the length of the conductors 8 between the microphone and the amplifier.
The invention is also of value in systems where the improved apparatus is used as a telephone receiver or loudspeaker. Such a system is illustrated in Fig. 3 where the reproducer I3 is energized through the anode resistance I4 from a battery I5 and is connected in the output circuit of the iinal amplifier tube I6 of a conventional amplifier.
It is to be noted that the microphone or telephone need not be directly connected with the associated amplifier as the great capacity thereof makes it possible to use a transformer which permits the impedance of the microphone or telephone to be transformed to any desired value.
I claim:
1. An acoustic device of the condenser type comprising a stationary elctrode and a dia- 50 phragm having a conducting aluminium foil, an Aabsorbent layer impregnated with glycerine, and
a layer of Celluloid adjacent the electrode.
2. An acoustic device of the condenser type comprising a stationary electrode and a diaphragm having a conducting gold foil, an absorbent layer impregnated with glycerine, and a layer of oelluloid adjacent the electrode.
3. An acoustic device of the condenser type comprising a stationary. electrode and a dia--v phragm having a conducting aluminium foil, an absorbentl layer impregnated -with glycerine, and a layer of collodion adjacent the electrode.
4. An acoustic device of the condenser type comprising a stationary electrode having openings therein, a conducting diaphragm overlying said electrode and a exible sheet interposed being a coating of -celluloid on the side in contact 10 with said stationary electrode.
EUGEN REISZ.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE2009520X | 1933-06-29 |
Publications (1)
Publication Number | Publication Date |
---|---|
US2009520A true US2009520A (en) | 1935-07-30 |
Family
ID=7951129
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US707190A Expired - Lifetime US2009520A (en) | 1933-06-29 | 1934-01-18 | Electroacoustic device |
Country Status (1)
Country | Link |
---|---|
US (1) | US2009520A (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3015051A (en) * | 1957-01-25 | 1961-12-26 | Sprague Electric Co | Electrical capacitor |
US3118979A (en) * | 1961-08-07 | 1964-01-21 | Bell Telephone Labor Inc | Electrostatic transducer |
US3135207A (en) * | 1955-07-05 | 1964-06-02 | Univ Cincinnati Res Foundation | Method and apparatus for displacing dielectric liquids |
FR2424683A1 (en) * | 1978-04-25 | 1979-11-23 | Polaroid Corp | PROCESS FOR MOUNTING A MEMBRANE IN AN ELECTROACOUSTIC TRANSDUCER, AND THUS OBTAINED TRANSDUCER |
-
1934
- 1934-01-18 US US707190A patent/US2009520A/en not_active Expired - Lifetime
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3135207A (en) * | 1955-07-05 | 1964-06-02 | Univ Cincinnati Res Foundation | Method and apparatus for displacing dielectric liquids |
US3015051A (en) * | 1957-01-25 | 1961-12-26 | Sprague Electric Co | Electrical capacitor |
US3118979A (en) * | 1961-08-07 | 1964-01-21 | Bell Telephone Labor Inc | Electrostatic transducer |
FR2424683A1 (en) * | 1978-04-25 | 1979-11-23 | Polaroid Corp | PROCESS FOR MOUNTING A MEMBRANE IN AN ELECTROACOUSTIC TRANSDUCER, AND THUS OBTAINED TRANSDUCER |
US4215249A (en) * | 1978-04-25 | 1980-07-29 | Polaroid Corporation | Method and device for controlling wrinkles in a vibratile diaphragm |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US3008014A (en) | Electrostatic loudspeakers | |
US3300585A (en) | Self-polarized electrostatic microphone-semiconductor amplifier combination | |
GB326602A (en) | Improvements in electro-static sound reproducers or transmitters | |
US2387845A (en) | Electroacoustic transducer | |
GB775854A (en) | Condenser-loudspeaker for reproduction of the higher frequency bands in the audible range and in which a foil is applied to a perforated metal sheet | |
US3084229A (en) | Electrostatic earphone | |
US3991285A (en) | Microphone having an electrostatic cartridge having a structural electrical resistor | |
US2009520A (en) | Electroacoustic device | |
US2282319A (en) | Leakage reducing means | |
US3082298A (en) | Frequency independent directional condenser microphone | |
US2468205A (en) | Volume controlled sound reinforcement system | |
GB1262505A (en) | Speaker system and electrostatic speaker | |
GB285315A (en) | Improvements in electrical pick-up and amplifying devices for use with gramophones and the like | |
GB1387453A (en) | Electrostatic electro-acoustic transducer | |
US3668336A (en) | Audio system including electrostatic loudspeaker | |
US2219729A (en) | Device employed in the conversion of electrical energy into acoustic energy and viceversa | |
US1978200A (en) | Electrostatic acoustic device | |
US2342822A (en) | Amplifying system | |
US1759811A (en) | Push-pull condenser speaker | |
US2266669A (en) | Hearing aid device | |
US3246287A (en) | Piezoelectric transformer | |
US2377121A (en) | Tone and volume control means | |
US2396691A (en) | Condenser transmitter-amplifier system | |
US2192669A (en) | Hearing aid device | |
JPS633443B2 (en) |