US1644992A - Means for transforming inaudible oscillations into audible oscillations - Google Patents

Means for transforming inaudible oscillations into audible oscillations Download PDF

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US1644992A
US1644992A US50159A US5015925A US1644992A US 1644992 A US1644992 A US 1644992A US 50159 A US50159 A US 50159A US 5015925 A US5015925 A US 5015925A US 1644992 A US1644992 A US 1644992A
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oscillations
casing
diaphragm
diaphragms
closures
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John E Davis
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04RLOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R13/00Transducers having an acoustic diaphragm of magnetisable material directly co-acting with electromagnet
    • H04R13/02Telephone receivers

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  • This invention relates to means for transforming inaudible sound oscillations of connected and the'means for connecting said Waves into audible ⁇ sound oscillations or cores with the magnet also being adapted to waves, and particularly adapted for use for mount the solenoid magnets and permanent connection in circuit with and influenced by magnet in the casing.
  • an electric oscillation receiving circuit and In the drawing accompanying and formit is the primary object of the invention to ing a part of this specification
  • Figure 1 is provide an improved constructed and ara side elevation of my improved transformer ranged transformer for this purpose to of inaudible sound oscillations into audio greatly intensify or amplify the audio osciloscillations. lations. 1
  • transformers of this character as heretofore constructed it has been the practice to effect the transforming of the inaudible sound oscillations through a vibratory diaphragm by mounting said diaphragm in a casing having an air space or chamber at one side of the diaphragm only in communication with asound emitting orifice or outlet in the casing to which outlet means is adapted to be connected to further amplify the audio oscillations transmitted by the diaphragm, and it is the principal object of right of Figure 1 with the end removed to show the arrangement and mounting of magnetic force generating means in the casing.
  • Figure 3 is a cross sectional view taken on the line 3-3 of Figure 2 to show the mounting of the diaphragms in relation to their actuating means.
  • I 1 Figure 4 is a perspective view,- partly broken away, of an end of the casing to show the arrangement of mounting a diaphragm thereon;
  • Figure 5 is a detail view in perspective on this purpose wherein both sides ofthe diaphragm are open to the air chamber in communication with the sound emitting outlet of the casing.
  • the embodiment of the invention illustrated is particularly adapted for. connection in circuit with an electric oscillation receiving circuit to transform electric oscillations into audio oscillations, and as comprising a casing with a pair of diaphragms arranged therein with both sides of each diaphragm open to an air space or chamber which is in communication with a sound emitting outlet from the casing. with magnetic force generating means to influence the diaphragms in unison interposed between the diaphragms and adapted for connection in circuit'with an electric oscillation receiving circuit, and
  • a casing comprisin a tubular member 6 having closures 7 an 8 removably connected to opposite ends of said member, as by arranging the two clofiange to have threaded connection with the tubular member, one of said closures having a central sound emit-ting outlet 9 having a tubular throat piece 10 mounted therein with a bayonet slot 11 at the outer end to adapt the casing for the releasable connection of an amplifier, such as a horn, to am lify the sound emitted from the outlet 9.
  • an amplifier such as a horn
  • lugs 12 circumferentially disposed in equidistant spaced relation about the same to extend radially inward from the closureflange in contiguous relation to the inner surface of the closures and each lug having a part 13 extending laterally and in a direction parallel with the axis magnets with the diaphragms operatively a greater number may be employed if depositioned relative to the cores thereof,- and sired.
  • FIG. 2 is an end elevation looking at the which the cores of the solenoid magnets are an enlarged scale to show the connection of sures with an internally threaded peripheral V ach threads on the inner Wall; While three of these lugs are shown in the present instance a permanent magnet to the pole portions of for diaphragms 14 and 15.
  • the diaphragms i are mounted on said seats by clamping the diaphragms between a pair of rings 16, 17 the ring 16 engaging the lugs and the ring 17 having screw threaded connection with therportions 13 projecting from the lugs.
  • e diaphragms are actuated or vibratedin unison by magnetic means adapted for connection 1n circuit with and influenced by an electric oscillation receiving circuit, such as a telephone circuit or radlo receiving circuit, said means comprising a permanent magnet 18 of split ring form and a pair of elect-ro-magnets 19, 20,-shownof the solenoid type and consisting of coils of wire wound about spools on cores 21, 22 of maglarly extended for connection with the other pole portion of the permanent magnet.
  • an electric oscillation receiving circuit such as a telephone circuit or radlo receiving circuit
  • the magnet cores 21, 22 are in effect pole pleces for and are secured to the permanent ma et by screws 23, 24 passing through openings Y t ere s in and from the exterior of the casing and openings in the ends of the magnet cores bent around the ermanent magnet and threaded into the atter, said screws also serving to mount and support the magnetic force generating means in the casing.
  • the portion of the cores at the ends of the spools opposite to the bent ends of the cores and intermediate the extended part thereof whereby they are connected to the permanent magnet are bent upon themselves in a direction toward each other and laterally of the spools, as shown at 26, whereby said portion will be arranged substantially centrally of the diaphragm 14 and facilitate the attracting of the central portion of the diaphragm thereto.
  • the permanent magnet is of smaller size than the casing to provide a space 25 between the magnet and easing.
  • one terminal 31 and 32 of each coil is connected to a contact member carried by and insulated from the casing member 6, said contacts comprising shouldered tubular members 33 inserted into and insulated from openings in the member 6 to which the coil terminals 31, 32 are connected by set screws 34 threaded into the contact and soldering, the said screws being in the nature of binding posts and also serving to retain contact plugs 35 connected to the conductors of the electric oscillation receiving circuit and inserted into the openings'in the contacts 33.
  • a casing having an opening, magnetic means mounted in fixed position in the casing adapted for connection in circuit with and influenced by an electric oscillation receiving circuit, a diaphragm, a closure for the casing opening having a central perforation to constitute an outlet for the casing and arranged for mounting of the diaphragm thereon in operative relation to the magnetic means to be actuated thereby and with an air space around the same in communication with the casing outlet, and said closure having an adjustable connection with the casing whereby the magnetic means and diaphragm are adapted to be variably adjusted one relative to the other.
  • a tubular member having a central aperture
  • said 010-- sures co-operating with the tubular member to provide a casing to which the aperture in the one closure serves'as an outlet and arranged for the mounting of the diaphragms thereon with the magnetic means interposed between and in operative relation to the diaphragm to vibrate the diaphragms in unison by variations induced in the magnetic field generated by the magnetic means through oscillations in the current flow of the electric oscillation receiving circuit
  • said closures having an adjustable connection with the tubular member whereby the diaphragms are adapted to have variable adjustment relative to each other and the magnetic means one independent of the other.
  • an open end casing In a transformer of electric oscillations into audio oscillations, an open end casing, magnetic force generating means mounted in the casing adapted for connection in circuit with and influenced by an electric oscillation receiving circuit, a closure for the open end of the casing having an opening arranged for the connection of sound amplifying means adjustably mounted on the and a diaphragm mounted on the closure with the closure opening in communication with an air space at opposite sides of the diaphragm and adapted to be variably positioned by the closure inoperative relation to the magnetic force ating means to be actuated thereby.
  • Iii a transformer of electric oscillations into audio oscillations, an open end casing
  • an open end casing In a transformer of electric oscillations into audio oscillations, an open end casing, magnetic force generating means mounted in the casing adapted for connection in circuit with and influenced by an electric oscillation receiving circuit, a closure having an adjustable connection with the open end of the casing and a sound emitting opening, and a diaphragm mounted and carried on the inner side of the closure arranged when the closure is connected to the casing to provide an air space at opposite sides of the diaphragm in open communication with the sound emitting opening in the closure.
  • a casing comprising a tubular member and a closure connected closures in variable operative relation to said magnetic force generating means to be actuated thereby.
  • the magnetic force generating means comprises a permanent; magnet and a pair of coils with the core of the one coil constituting a, pole piece connected to one pole of the permanent magnet and the core of the other coil constituting a pole piece connected to the other pole of thepermanent magnet.
  • a casing including threaded connection with said member one of said closures having an opening to constitute an outlet .
  • a ring form permanent magnet for the casing and lugs extending laterally from the inner side thereof, a ring form permanent magnet, pole pieces connected to the poles of the magnet arranged to position the pole pieces within the magnet and the terminals of the pole pieces to extend in parallel relation transversely of the magnet, electromagnetic force generatin means mounted on said pole piece, a diaphragm, and means to mount the diaphragm upon the closure lugs whereb the casing outlet is in communication wit an air space within the casing extending around both sides of the diaphragm.
  • each of the closures is arranged with lugs extending laterally from the inner side thereof for the mounting of a dia- .phragm upon each of the closures with the casing outlet in communication with an air space in the casing extending around both sldes of each diaphragm.
  • contact terminals mounted on and insulated from the tubular member of the casing adapted for electrical connection of the magnetic force generating means and for connection of electric current conductors exterior of the casing.

Description

Oct. 11,1927. J E DAWS 1,644,992
MEANS FOR TRANSFORMING INAUDIBLE OSCILLATIONS INTO AUDIBLE OSCILLATIONS Filed Aug. 14, 1925 IN VENT OR 42/01); D12 Z/ZS the invention to provide a transformer for said means: including a pair of solenoid Patented Oct. 11, 1927. r a UNITED STATES PATENT OFFICE.
JOHN E; DAVIS, OF BROOKLYN, NEW YORK.
MEANS FOR TRANSFORMIN G INAUDIBLE OSCILLATIONS INTO AUDIBLE OSCILLATIONS.
Application filed August 14, 1925. Serial No. 50,159,
This invention relates to means for transforming inaudible sound oscillations of connected and the'means for connecting said Waves into audible \sound oscillations or cores with the magnet also being adapted to waves, and particularly adapted for use for mount the solenoid magnets and permanent connection in circuit with and influenced by magnet in the casing. an electric oscillation receiving circuit, and In the drawing accompanying and formit is the primary object of the invention to ing a part of this specification Figure 1 is provide an improved constructed and ara side elevation of my improved transformer ranged transformer for this purpose to of inaudible sound oscillations into audio greatly intensify or amplify the audio osciloscillations. lations. 1
In transformers of this character as heretofore constructed it has been the practice to effect the transforming of the inaudible sound oscillations through a vibratory diaphragm by mounting said diaphragm in a casing having an air space or chamber at one side of the diaphragm only in communication with asound emitting orifice or outlet in the casing to which outlet means is adapted to be connected to further amplify the audio oscillations transmitted by the diaphragm, and it is the principal object of right of Figure 1 with the end removed to show the arrangement and mounting of magnetic force generating means in the casing.
Figure 3 is a cross sectional view taken on the line 3-3 of Figure 2 to show the mounting of the diaphragms in relation to their actuating means. I 1 Figure 4 is a perspective view,- partly broken away, of an end of the casing to show the arrangement of mounting a diaphragm thereon; and
Figure 5 is a detail view in perspective on this purpose wherein both sides ofthe diaphragm are open to the air chamber in communication with the sound emitting outlet of the casing.
It is a further. object of the invention to provide a transformer of this character arranged with a pairof diaphragms adapted to be operated in unison with both sides of each, diaphragm open to an air space or chamber in communication with the sound emitting outlet of the diaphragm carrying casing.
Other objects and advantages will hereinafter appear. I
The embodiment of the invention illustrated is particularly adapted for. connection in circuit with an electric oscillation receiving circuit to transform electric oscillations into audio oscillations, and as comprising a casing with a pair of diaphragms arranged therein with both sides of each diaphragm open to an air space or chamber which is in communication with a sound emitting outlet from the casing. with magnetic force generating means to influence the diaphragms in unison interposed between the diaphragms and adapted for connection in circuit'with an electric oscillation receiving circuit, and
the cores of the solenoid magnets with the pole portions of the permanent magnet and the mounting of the solenoid magnets'and permanent magnet in the casing.
In the embodiment of the invention illustrated there is provided a casing comprisin a tubular member 6 having closures 7 an 8 removably connected to opposite ends of said member, as by arranging the two clofiange to have threaded connection with the tubular member, one of said closures having a central sound emit-ting outlet 9 having a tubular throat piece 10 mounted therein with a bayonet slot 11 at the outer end to adapt the casing for the releasable connection of an amplifier, such as a horn, to am lify the sound emitted from the outlet 9. of the closures has lugs 12 circumferentially disposed in equidistant spaced relation about the same to extend radially inward from the closureflange in contiguous relation to the inner surface of the closures and each lug having a part 13 extending laterally and in a direction parallel with the axis magnets with the diaphragms operatively a greater number may be employed if depositioned relative to the cores thereof,- and sired. These lugs constitute supporting seats Figure 2 is an end elevation looking at the which the cores of the solenoid magnets are an enlarged scale to show the connection of sures with an internally threaded peripheral V ach threads on the inner Wall; While three of these lugs are shown in the present instance a permanent magnet to the pole portions of for diaphragms 14 and 15. The diaphragms i are mounted on said seats by clamping the diaphragms between a pair of rings 16, 17 the ring 16 engaging the lugs and the ring 17 having screw threaded connection with therportions 13 projecting from the lugs.
e diaphragms are actuated or vibratedin unison by magnetic means adapted for connection 1n circuit with and influenced by an electric oscillation receiving circuit, such as a telephone circuit or radlo receiving circuit, said means comprising a permanent magnet 18 of split ring form and a pair of elect-ro- magnets 19, 20,-shownof the solenoid type and consisting of coils of wire wound about spools on cores 21, 22 of maglarly extended for connection with the other pole portion of the permanent magnet. The magnet cores 21, 22 are in effect pole pleces for and are secured to the permanent ma et by screws 23, 24 passing through openings Y t ere s in and from the exterior of the casing and openings in the ends of the magnet cores bent around the ermanent magnet and threaded into the atter, said screws also serving to mount and support the magnetic force generating means in the casing. The portion of the cores at the ends of the spools opposite to the bent ends of the cores and intermediate the extended part thereof whereby they are connected to the permanent magnet are bent upon themselves in a direction toward each other and laterally of the spools, as shown at 26, whereby said portion will be arranged substantially centrally of the diaphragm 14 and facilitate the attracting of the central portion of the diaphragm thereto. The permanent magnet is of smaller size than the casing to provide a space 25 between the magnet and easing.
By the arrangement of mounting the di a hragms upon the casing closures 7 and 8 I rovided an air space or chamber at both sldes of the diaphragm 15 which is in communication withthe sound emitting orifice 9 of the casing, and an air space or chamber is also provided at both s des of the diaphragm 14 which is in communication. with the sound orifice 9 through the space between the permanent magnet and easing. wall. It will be obvious that as both sides of the diaphragm 15 are in open communication with the sound emitting 'orlfice- 9 enhanced or intensified audio osclllations are transmitted from the casing outlet, and that these audio oscillations will be fur-' ther enhanced and intensified by the arrangement of the other diaphragm 14 with both sides thereof in communication with an air space communicating with the outlet ori- By the arrangement of the threaded connection of the closures 7 and 8 with the casing member 6 and the mounting of the 7 (liaphragms on said closures the diaphragm actuatin means and the diaphragms may be varia'ily adjusted relative to each other by screwing the closures onto and off from the tubular member 6 and then securing the s0 closures in adjusted position by'set screws 30 passed through the flange of the closures and engaging with the screw threads on the member 6.
To connect the coils of the solenoids 19, 20
in circuit with an electric oscillation receiving circuit to be influenced thereby and actuate the diaphragms one terminal 31 and 32 of each coil is connected to a contact member carried by and insulated from the casing member 6, said contacts comprising shouldered tubular members 33 inserted into and insulated from openings in the member 6 to which the coil terminals 31, 32 are connected by set screws 34 threaded into the contact and soldering, the said screws being in the nature of binding posts and also serving to retain contact plugs 35 connected to the conductors of the electric oscillation receiving circuit and inserted into the openings'in the contacts 33.
While I have illustrated the invention as embodying a pair of dia hr ams, it will be obvious t at only one iap ragm may be utilized, and that in the use of the two diaphragms each of the closures may be arranged for the connection of a sound amplifying horn thereto. Furthermore, various modifications may be made in construction and arrangement of parts and ortions of the invention may be used wit out others and come within the scope of the invention. While I have illustrated and described the, invention as being particularly applicable for the transforming of electrical oscillatime into audio oscillations wherein the diaphragm or diaphragms are actuated by magnetic means influenced through the variations in the electric oscillations, it is to be understood that the same is applicable to sound boxes of sound reproducing machines by connecting the stylus carrier to one diaphragm and where more than one dia phragm is utilized interconnecting the diaghra ms so that all of the diaphragms 111 5 e W rated in unison through the actuation of the one diaphragm by the stylus carrier.
1Having thus described my 1nvention,'I 'c aim:
1. In a transformer of electric oscillations 3 casin into audio oscillations, a casing having an opening, magnetic means mounted in fixed position in the casing adapted for connection in circuit with and influenced by an electric oscillation receiving circuit, a diaphragm, a closure for the casing opening having a central perforation to constitute an outlet for the casing and arranged for mounting of the diaphragm thereon in operative relation to the magnetic means to be actuated thereby and with an air space around the same in communication with the casing outlet, and said closure having an adjustable connection with the casing whereby the magnetic means and diaphragm are adapted to be variably adjusted one relative to the other.
. 2. In a transformer of electric oscillations into audio oscillations, a tubular member, magnetic means mounted in said member adapted for connection in circuit with and influenced by an electric oscillation receiving circuit, a pair of diaphraghms, a closure for each end of the tubular member one of said closures having a central aperture, said 010-- sures co-operating with the tubular member to provide a casing to which the aperture in the one closure serves'as an outlet and arranged for the mounting of the diaphragms thereon with the magnetic means interposed between and in operative relation to the diaphragm to vibrate the diaphragms in unison by variations induced in the magnetic field generated by the magnetic means through oscillations in the current flow of the electric oscillation receiving circuit, and said closures having an adjustable connection with the tubular member whereby the diaphragms are adapted to have variable adjustment relative to each other and the magnetic means one independent of the other.
3. A transformer of electric oscillations into audio oscillations as claimed in claim 2 wherein the diaphragms are arranged with an air chamber extending around opposite sides of the diaphragms and in communication with the outlet of the casing.
4. In a transformer of electric oscillations into audio oscillations, an open end casing, magnetic force generating means mounted in the casing adapted for connection in circuit with and influenced by an electric oscillation receiving circuit, a closure for the open end of the casing having an opening arranged for the connection of sound amplifying means adjustably mounted on the and a diaphragm mounted on the closure with the closure opening in communication with an air space at opposite sides of the diaphragm and adapted to be variably positioned by the closure inoperative relation to the magnetic force ating means to be actuated thereby.
5. Iii a transformer of electric oscillations into audio oscillations, an open end casing,
genera tubular member with disk closures forthe opposite ends having threaded flanges for r lugs being constructed and arranged to position the diaphragm in operative relation to the magnetic force generating means and provide a space at both sides of the diaphragm in open communication with the sound emitting opening.
6. In a transformer of electric oscillations into audio oscillations, an open end casing, magnetic force generating means mounted in the casing adapted for connection in circuit with and influenced by an electric oscillation receiving circuit, a closure having an adjustable connection with the open end of the casing and a sound emitting opening, and a diaphragm mounted and carried on the inner side of the closure arranged when the closure is connected to the casing to provide an air space at opposite sides of the diaphragm in open communication with the sound emitting opening in the closure.
7. In a transformer of electric oscillations into audio oscillations, a casing comprising a tubular member and a closure connected closures in variable operative relation to said magnetic force generating means to be actuated thereby.
8. A transformer of electric oscillations into audio oscillations as claimed in claim 7, wherein the magnetic force generating means comprises a permanent; magnet and a pair of coils with the core of the one coil constituting a, pole piece connected to one pole of the permanent magnet and the core of the other coil constituting a pole piece connected to the other pole of thepermanent magnet.
9. In a transformer of electric oscillationsinto audio oscillations, a casing including threaded connection with said member one of said closures having an opening to constitute an outlet .for the casing and lugs extending laterally from the inner side thereof, a ring form permanent magnet, pole pieces connected to the poles of the magnet arranged to position the pole pieces within the magnet and the terminals of the pole pieces to extend in parallel relation transversely of the magnet, electromagnetic force generatin means mounted on said pole piece, a diaphragm, and means to mount the diaphragm upon the closure lugs whereb the casing outlet is in communication wit an air space within the casing extending around both sides of the diaphragm.
10. A transformer of electric oscillations into audio oscillations as claimed in claim 9, wherein each of the closures is arranged with lugs extending laterally from the inner side thereof for the mounting of a dia- .phragm upon each of the closures with the casing outlet in communication with an air space in the casing extending around both sldes of each diaphragm.
11. A transformer of electric oscillations into audio oscillations as claimed in claim 9, wherein the electromagnetic force generating means comprises a pair of coils one mounted on each pole piece.
12. In a transformer of electric oscillations into audio oscillations as claimed in claim 9, contact terminals mounted on and insulated from the tubular member of the casing adapted for electrical connection of the magnetic force generating means and for connection of electric current conductors exterior of the casing.
Signed at New York city, in the county v of New York and State of New York, this 6th day of August, 1925.
JOHN E. DAVIS.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4151379A (en) * 1978-03-01 1979-04-24 Ashworth William J Electromagnetic speaker with bucking parallel high and low frequency coils drives sounding board and second diaphragm or external apparatus via magnetic coupling and having adjustable air gap and slot pole piece

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4151379A (en) * 1978-03-01 1979-04-24 Ashworth William J Electromagnetic speaker with bucking parallel high and low frequency coils drives sounding board and second diaphragm or external apparatus via magnetic coupling and having adjustable air gap and slot pole piece

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