[go: up one dir, main page]

US2510079A - Velocity microphone with ribbon supported along its edges - Google Patents

Velocity microphone with ribbon supported along its edges Download PDF

Info

Publication number
US2510079A
US2510079A US717261A US71726146A US2510079A US 2510079 A US2510079 A US 2510079A US 717261 A US717261 A US 717261A US 71726146 A US71726146 A US 71726146A US 2510079 A US2510079 A US 2510079A
Authority
US
United States
Prior art keywords
ribbon
edges
diaphragm
microphone
inch
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
Application number
US717261A
Other languages
English (en)
Inventor
Cragg William Donald
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
International Standard Electric Corp
Original Assignee
International Standard Electric Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by International Standard Electric Corp filed Critical International Standard Electric Corp
Application granted granted Critical
Publication of US2510079A publication Critical patent/US2510079A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

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
    • H04R9/00—Transducers of moving-coil, moving-strip, or moving-wire type
    • H04R9/02—Details
    • H04R9/04—Construction, mounting, or centering of coil
    • H04R9/046—Construction
    • H04R9/047—Construction in which the windings of the moving coil lay in the same plane
    • H04R9/048—Construction in which the windings of the moving coil lay in the same plane of the ribbon type
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R7/00—Diaphragms for electromechanical transducers; Cones
    • H04R7/02—Diaphragms for electromechanical transducers; Cones characterised by the construction
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R9/00—Transducers of moving-coil, moving-strip, or moving-wire type
    • H04R9/08—Microphones

Definitions

  • This invention relates to velocity (or pressure gradient) microphones.
  • the object of thisinvention isgto avoid Ycertain constructional-lfeaturesinherent inv microphonesof this ,type atpr'esent in use which render it'impossibletoA use the-magnetic i'leld efficiently, and result in dimensions far greater. thanY are ideally necessary.;
  • Such microphones are usually oi the ribbon type in which the diaphragm, is 'an aluminum ribbon ofthe order of 2" long X 0.27; Wide x 0.000,2"
  • stiffness of the suspensionA must be Avery low ivl;1ich ⁇ . n
  • thedeothof. .theA airesao must be about 0.1 Whereas themovement oi the; ribbon due 4to a soundjield; is not greater than- According ,tothe present. invention.
  • the invention was irsttried out experimentally with a at gold leaf ribbon 4, Figures 1 and 2 about 5.10-6 inches thick which was mounted slackly between and attached to the pole-pieces 2, 3 carried by a semi-circular magnet I.
  • the rib- 2 .i bon was longerthan the pole pieces and wasn also Y fixed at its end to which theelectricalconnec-,U tions were made.
  • va ribbon microphone is a masscontrolled.. devicethere is iorribbonspf.identical duinen- ⁇ sions a loss of. about 20 db, in using goldl instead,V 0i. aluminium, the .specie gravity. of. sold.. being 19.5 Ycompared with V2.5 for,aluminium.V
  • This .construction is capableoi producing. a ,l microphone with asensitivity oi 90 db... below 1 volt/dyne/sq.- .cm. for, a gold rilobnmfl .,25,..0hm s resistance.
  • the dimensions of the gap being, in a preferred embodiment, 0.156 inch wide x 0.0625 inch deep (pole-tip width).
  • the response at high frequencies can be irnproved by the use of cavity resonances on conventional lines.
  • the ribbon has three corrugations on each side of the aluminum armature, the corrugations having a lateral depth of about .O inch with a radius of .010 inch.
  • Figures 1 and 2 are twice full scale, while Figure 3 is twenty-live times full size.
  • the pole pieces are chamfered down to very narrow lateral dimensions, ls of an inch, at their tips, this being possible because the static position of the ribbon is closely defined.
  • the ribbon was mounted on the side of the pole pieces in an experimental model, but it will normally be cated symmetrically in the air gap, by dividing the pole pieces longitudinally and assembling the ribbon so that its edges are sandwiched between the divided pole-pieces.
  • the construction shown in Figures 4 and 5 may be employed.
  • the central stii area I9 of a thermo-plastic ribbon d has a cross-sectional form comprising two similar curved halves meeting at a central longitudinal apex on which is mounted a wire armature 6 of about .008 inch diameter.
  • the ribbon is longitudinally corrugated on each side of the central stiff portion, the corrugations 5 having a preferred radius of .025 inch and overall depth of .020 inch.
  • the semi-circular magnet I carries iiat pole pieces 2, 3 with apertures 9 designed to give the maximum possible air path to the diaphragm without increasing the reluctance of the magnetic circuit, and so that the diaphragm will respond to frequencies below 10,000 C. P. C. as if it were freely open to the air on both sides.
  • the pole tips l are narrowed down to very small lateral dimensions, 12- of an inch, and are very closely spaced to define a narrow air gap 8: about 0.18 inch wide, to receive the wire armature I5 of .008 inch diameter.
  • the ribbon 4 is mounted along its longitudinal edges on spacers I3 about .015 inch thick on the pole pieces with the wire 6 positioned in the gap 3.
  • wire armature II Figure 5 is connected by copper tapes II spot-welded or otherwise fixed thereto, to terminals I2.
  • the two longitudinal corrugated halves 5a, 5b of the diaphragm on either side of electrode may be in different planes and facing in opposite directions as shown in Fig. 6, so that the two halves will be located on opposite sides of the plane of the magnet poles 2, 3 with the central stili portion of the diaphragm at anV angle thereto and passing through the air gap 3 and carrying the electrode 3 therein.
  • This has the advantage that the resonant chambers I4, I5Y
  • resonant chambers I4, I5 both on the same side of the poles 2, 3 for some purposes, e. g. when the microphone is used in combination with a pressure microphone for matching purposes. In other circumstances, the arrangement shown in Fig. 6 will be advantageous.
  • a ribbon type velocity microphone comprising a structure of magnetic material having an air gap therein, a resilient ribbon having one longitudinal edge attached to the inside of said structure by a corrugated support and the other longitudinal edge attached to the outside of the structure by a similar support, said supports forming resonant cavities with the walls of said structure, said diaphgram passing through the air gap, and a linear conductor mounted on the ribbon within gap.
  • a ribbon type velocity microphone comprising a structure of magnetic material having an air gap therein, a resilient corrugated ribbon having one longitudinal edge attached to the inside of said structure by a corrugated support and the other longitudinal edge attached to the outside of the structure by a similar support, said supports forming resonant cavities with the walls of said structure, said diaphragm passing through the air gap, and a linear conductor mounted on the ribbon within the air gap.
  • a ribbon type velocity microphone comprising a structure of magnetic material having an air gap therein, a resilient diaphragm having a series of uneven longitudinal corrugations to vary the stillness thereof having one longitudinal edge attached to the inside of said structure by a corrugated support and the other longitudinal edge attached to the outside of the said structure by a similar support, said supports forming resonant cavities with the walls of said structure; said diaphragm passing through the air gap, the transverse dimension of the corrugated resilient diaphragm having a progressive variation in the longitudinal direction with respect to the width of the air gap to give progressively different resonant periods along different sections of the diaphragm, and a linear conductor mounted longitudinally on said diaphragm within said air gap.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Multimedia (AREA)
  • Audible-Bandwidth Dynamoelectric Transducers Other Than Pickups (AREA)
  • Diaphragms For Electromechanical Transducers (AREA)
US717261A 1945-12-11 1946-12-19 Velocity microphone with ribbon supported along its edges Expired - Lifetime US2510079A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB264459X 1945-12-11

Publications (1)

Publication Number Publication Date
US2510079A true US2510079A (en) 1950-06-06

Family

ID=10243722

Family Applications (1)

Application Number Title Priority Date Filing Date
US717261A Expired - Lifetime US2510079A (en) 1945-12-11 1946-12-19 Velocity microphone with ribbon supported along its edges

Country Status (6)

Country Link
US (1) US2510079A (es)
BE (1) BE472060A (es)
CH (1) CH264459A (es)
ES (1) ES177013A1 (es)
FR (1) FR936879A (es)
GB (1) GB625013A (es)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2207833B (en) * 1987-08-05 1990-10-31 Advanced Acoustics Limited Microphone assembly

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB220420A (en) * 1919-11-18 1924-08-21 Adrian Francis Sykes Improved electro-magnetic means for transmitting and reproducing sound
US1902643A (en) * 1930-10-30 1933-03-21 Westinghouse Electric & Mfg Co Electrical translating device
US2106224A (en) * 1933-11-21 1938-01-25 Rca Corp Device for transforming acoustical energy into electrical energy
US2141420A (en) * 1936-07-28 1938-12-27 Bell Telephone Labor Inc Acoustic device
US2164157A (en) * 1936-07-11 1939-06-27 Electrical Res Prod Inc Acoustic device
GB511034A (en) * 1937-12-31 1939-07-31 Henry John Houlgate Improvements in and relating to electric acoustic devices
US2183209A (en) * 1936-09-30 1939-12-12 Rca Corp Electroacoustical apparatus

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB220420A (en) * 1919-11-18 1924-08-21 Adrian Francis Sykes Improved electro-magnetic means for transmitting and reproducing sound
US1902643A (en) * 1930-10-30 1933-03-21 Westinghouse Electric & Mfg Co Electrical translating device
US2106224A (en) * 1933-11-21 1938-01-25 Rca Corp Device for transforming acoustical energy into electrical energy
US2164157A (en) * 1936-07-11 1939-06-27 Electrical Res Prod Inc Acoustic device
US2141420A (en) * 1936-07-28 1938-12-27 Bell Telephone Labor Inc Acoustic device
US2183209A (en) * 1936-09-30 1939-12-12 Rca Corp Electroacoustical apparatus
GB511034A (en) * 1937-12-31 1939-07-31 Henry John Houlgate Improvements in and relating to electric acoustic devices

Also Published As

Publication number Publication date
CH264459A (de) 1949-10-15
ES177013A1 (es) 1947-04-16
GB625013A (en) 1949-06-21
BE472060A (es)
FR936879A (fr) 1948-08-02

Similar Documents

Publication Publication Date Title
US4037061A (en) Planar pattern voice coil audio transducer
US4584439A (en) Audio transducer with controlled flexibility diaphragm
US4276449A (en) Speaker or microphone having corrugated diaphragm with conductors thereon
US3651283A (en) Loudspeaker having elongated rectangular moving coil
US3209084A (en) Electro-acoustical transducer
US8942408B1 (en) Magnetically one-side driven planar transducer with improved electro-magnetic circuit
US3066200A (en) Speaker device
US2896025A (en) Electrostatic loudspeaker
US20210049992A1 (en) Loudspeaker
US4020296A (en) Electroacoustic transducer
US3171904A (en) Electrodynamic loud-speakers and microphones
US2510079A (en) Velocity microphone with ribbon supported along its edges
US2582942A (en) Electroacoustical transducer
CN207968953U (zh) 一种电枢及受话器
US6111972A (en) Diffusing volume electroacoustic transducer
CN207603908U (zh) 一种振膜
US5912863A (en) Electro-acoustic transducer
US1974895A (en) Electromagnetic reproducer
US2379282A (en) Recorder
US2552311A (en) Ribbon support for high fidelity electroacoustical sound transducers
US1671105A (en) Actuating device for loud speakers
US7747035B1 (en) Unipole radiator loudspeaker
US1768903A (en) Sound-producing device
US2677105A (en) Bifilar suspension
KR850002567Y1 (ko) 평면진동파 스피커