US1934184A - Electrodynamic loud speaker - Google Patents

Electrodynamic loud speaker Download PDF

Info

Publication number
US1934184A
US1934184A US583297A US58329731A US1934184A US 1934184 A US1934184 A US 1934184A US 583297 A US583297 A US 583297A US 58329731 A US58329731 A US 58329731A US 1934184 A US1934184 A US 1934184A
Authority
US
United States
Prior art keywords
diaphragm
coil
pole
magnet
sound wave
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
US583297A
Other languages
English (en)
Inventor
Gerlach Erwin
Orlich Heinz
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.)
Siemens and Halske AG
Siemens Corp
Original Assignee
Siemens 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 Siemens Corp filed Critical Siemens Corp
Application granted granted Critical
Publication of US1934184A publication Critical patent/US1934184A/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
    • H04R7/00—Diaphragms for electromechanical transducers; Cones
    • H04R7/02—Diaphragms for electromechanical transducers; Cones characterised by the construction
    • H04R7/12—Non-planar diaphragms or cones
    • H04R7/14—Non-planar diaphragms or cones corrugated, pleated or ribbed
    • 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
    • H04R7/16—Mounting or tensioning of diaphragms or cones
    • H04R7/18—Mounting or tensioning of diaphragms or cones at the periphery
    • H04R7/22—Clamping rim of diaphragm or cone against seating
    • 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
    • H04R9/06—Loudspeakers

Definitions

  • Horn loud speakers based upon the electrodynamic drive principle are fundamentally known in the art. These known loudspeaker constructions generally comprise a circular, calotteshaped or conical diaphragm with a circular oscillation coil. Other known embodiments are loud speakers with four pole magnet systems.
  • the magnet system in this case is adapted to the form'of a coil, just as in the known loud speakers with square coils whose magnet system consists of a square middle pole and two pole shoes which are disposed upon two opposite sides of the central pole.
  • the diaphragm In order to insure faithful reproduction and a high efiiciency it is imperative to make the oscillating system as light in weight as feasible and to raise the field intensity of the air-gap to a maximum value. However, the lightness of the diaphragm should not be driven to a point where rigidity is impairedas a consequence. In fact, up to the highest frequencies, generally up to 3,000 cycles, the diaphragm should oscillate en bloc or piston fashion (as a rigid whole) ,and this is possible only if the diaphragm is of maximum stiffness.
  • two natural periods arise. They are, namely, one natural period in longitudinal sense and another one in transversal direction.
  • the former does not make itself unfavorably felt because of the cophasicdrive of the diaphragm so that the diaphragm can be made any desired length.
  • the load capacity may thus also be raised at will in contradistinction towhat is true to diaphragi'ns known in the earlier art-where an increase in surface occasions a reduction in the natural period whereby reproduction owing tothe occurrence of the resonance peak is substantially reduced.
  • the width of the diaphragm may be readily chosen so that the transversal vibration of the diaphragm can be shifted to. a very high point, in fact. close to the limit of the frequency range or band preferably or predominantly to be re produced.
  • the transversal vibration may also be vshifted by means of reinforcement ribs or ins and corrugations as is well known in the art.
  • the weight of the diaphragm in this manner may diaphragm possessing identical acoustic properties. According to the present invention it has been feasibleto develop systems in which, in the presenceof a transversal natural vibration of about 6,000 cycles, 1, e., a diaphragm of great rigidity the oscillating system (diaphragm; and
  • the diaphragm may be considered, compared toll) the transformation space, as an air tight diaphragm since a pressure transformation of a ratio of at least 1:10 is provided for the purpose of increasing the efiiciency. This is the ideal oscillating diaphragm to be striven for.
  • the marginal drive prevents the arising of partial vibrations in the diaphragm.
  • the leverage between the driving force and the supporting means is nearly of zero value due to the fact that the driving force acts upon the diaphragm in the neighborhood of the diaphragm supporting means. As a result the diaphragm is able to respond en bloc (piston fashion) to the motions of the coil.
  • Simple straight ground magnet pieces may be used for the constructure of the magnet system.
  • the magnet system may also consist of a-U -shaped piece having the preferably rectangular and elongated middle pole disposed inthe middle thereof.
  • pole plates are placed upon the lateral limbs. If desired the plates may be connected by means of screws and slots with the lateral limbs in order to allow for an adjustment of the air gap between the pole plate and'the center pole.
  • the shape of the elongated rectangle for the center pole may be chosen very short in reference'to the aggregate conductor length.
  • the diaphragm is furnished with transversal fins or. ribs in order that the transversal vibrations may be shiitedas high as possible. If this diaphragm is fitted into the mouth of the horn or funnel, then the compression space is unnecessarily enlarged by the space between the reinforcing ribs or fins or corrugations, and the efficiency of the entire arrangement is diminished.
  • the acoustically active surface is smoothed by covering the surface of the diaphragm with tissue paper, ordinary paper, thin metal foil or some other layerof suitable substance so that the-compression space is correctly pre-calculable and may be chosen and fixed at the optimum value from a technical viewpoint.
  • the covering layer is somewhat'wider than the width of the diaphragm so that strips protrudeat the longitudinaledges' of the diaphragm, these strips being adapted to be fixed to the outer poles.
  • the covering surface inthis manner also serves to support the diaphragm.
  • Fig. 1 is an isometric view showing the magnet system and the field winding
  • Fig. 2- is an isometric view showing an approved iorm ofthe assembled diaphragm
  • Fig. 3 is an isometric view showing a diaphragm having a modified form of driving conductor
  • Fig. 6 is a, side view of the assembled appara-
  • the system 1 preferably made in one piece and plates 2 as well as the center pole plate 3.
  • the pole plates are adjustably secured to the poles by means of screws passing through slots in the pole plates.
  • the interiorly disposed field coil 4 is readily able to give oil dissipated heat on its transversal faces inasmuch as the same is in contact with the outside air, in contradistinction with the usual forms of construction of electrodynamic loud speakers where the magnet coil is located inside the pot.
  • Abduction'of heat is furthermore promoted by the aid of sheets or lamina: 5 consisting of material possessing high heat conducting powers, which are inserted in the field coil.
  • Fig. 2 shows the oscillation coil 6 with the diaiio phragm 7 (not shown in Fig. l)
  • the diaphragm phragm The attachment is preferably obtained by-means of pasting.
  • Fig. 3 shows the diaphragm and the .system without the surface 8.
  • Figl 4 shows, partly in section, an embodiment of the novel loud speaker which differs from the embodiment shownin Figs. 1-3, as regards the mode of securing or attaching the diaphragm.
  • the coil 14 is carrying the speech or audiofrequency currents projects into the' air gap between thefcentral pole-12 and the pole plates 13.-
  • The'coil 14' consisting of a single turn
  • the diaphragm 17 is fastened to a piece of silk material 18 which extends over a frame 19. The said frame 19 is secured to the plates 13.
  • a spacer frame 21 consisting of hard paper or sheet metal material is placed between the frame 19 which is screwed fast on the outer pole plates 13, and the flange 20.
  • the pressure transformation space 22 is easily adjustable in this manner.
  • the flange 20 is connected through the long equal length tubes 23 as shown in Fig. 6, with the attaching piece 24 which is adjacent to the mouth of the horn.
  • a vibratile system for an electrodynamic acoustic device comprising a pair of conductors and an elongated box-like structure open at its bottom and at its two shorter ends, the top of said structure constituting a sound wave producing portion, and the longer sides of said structure constituting supports for said conductors, said sides and said conductors constituting the driving portion of said vibratile system.
  • a vibratile system for an acoustic device of the electrodynamic type comprising an elongated rectangularly shaped sound wave producing portion, reinforcing means for said sound wave producing portion consisting of corrugations extending transversely of said sound wave producing portion, and a driving portion consisting of strips of hard paper connected along their edges substantially to the longitudinal edges of-the sound wave producing portion, and a conductor pressed around said strips of hard paper.
  • a vibratile system for an acoustic device of the electro-dynamic type comprising a sound Wave producing portion, a driving portion, reinforcing means for said sound wave producing portion comprising corrugations extending at right angles to the direction of motion of said driving portion, and a layer of silk covering the corrugations in said sound wave producing portion and extending beyond the limits of said sound wave producing portion to provide means for fastening the vibratile system to the outer pole pieces of the magnet system.
  • a magnet system for an electro-dynamic acoustic device comprising an elongated magnet which is substantially E-shaped in cross section, a winding surrounding the middle limb of said magnet arranged so that it is exposed to the outer air at the ends of said magnet, cooling fins imbedded in said winding and extending from the ends thereof'into the open air, and pole plates secured to each of the limbs of said magnet and arranged to provide a pair of elongated air gaps.
  • a magnet for an electro-dynamic acoustic device comprising an elongated magnet system which is substantially E-shaped in cross section, a winding surrounding the middle limb of said magnet system arranged so that it is exposed to the outer air at the ends of said system, pole plates secured to each of the limbs of said magnet system and arranged to provide a pair of elongated air gaps, and laminae of material having high heat conducting properties inserted in said coil and extending outwardly therefrom into the open air whereby heat from said coil is readily dissipated.
  • a loud speaker of the electro-dynamic type comprising a magnet system for providing an electro-magnetic field, a diaphra m.
  • said diaphragm consisting of a conductor portion adapted to cooperate with said magnetic field and an elongated rectangularly shaped sound wave producing portion, means providing a compression space above saidsound'wave producing portion, and channels for connecting said compression space with an acoustic horn.
  • a loud speaker of the electro-dynamic type comprising a magnet system for providing an electro-magnetic field, a diaphragm, said diaphragm consisting of a conductor portion adapted to cooperate with said magnetic field and an elongated rectangularly shaped sound 'wave producing portion, means providing a compression space above said sound wave producing portion and channels for connecting said compression space with an acoustic horn, said channels consisting of a plurality of tubes of equal length extending between a common aperture at the smaller opening of said horn and different points along said elongated diaphragm.
  • An acoustic device of the electro-dynamic type comprising means providing a magnetic field, a diaphragm consisting of a portion for cooperating with said magnetic field and a sound wave producing portion, said sound wave producing portion having an elongated rectangular shape, a layer of silk covering said sound wave producing portion and extending there beyond, a frame to which is secured the portion of said layer of silk extending beyond said sound wave producing portion, and means for fastening said frame to' said magnet system.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Multimedia (AREA)
  • Audible-Bandwidth Dynamoelectric Transducers Other Than Pickups (AREA)
US583297A 1930-09-17 1931-12-26 Electrodynamic loud speaker Expired - Lifetime US1934184A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE599805T 1930-09-17

Publications (1)

Publication Number Publication Date
US1934184A true US1934184A (en) 1933-11-07

Family

ID=34608816

Family Applications (1)

Application Number Title Priority Date Filing Date
US583297A Expired - Lifetime US1934184A (en) 1930-09-17 1931-12-26 Electrodynamic loud speaker

Country Status (4)

Country Link
US (1) US1934184A (en(2012))
DE (1) DE599805C (en(2012))
FR (1) FR722913A (en(2012))
NL (1) NL33150C (en(2012))

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2691148A (en) * 1950-06-24 1954-10-05 Rca Corp Ultrasonic transducer
US3198890A (en) * 1961-06-14 1965-08-03 Rosen Alfred H High fidelity sound reproducer
US4354066A (en) * 1980-09-15 1982-10-12 Necoechea Robert W Rigid-diaphragm transducer with plural coils
US20020114214A1 (en) * 2001-01-26 2002-08-22 Hansen Kaj Borge Electroacoustic transducer

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2691148A (en) * 1950-06-24 1954-10-05 Rca Corp Ultrasonic transducer
US3198890A (en) * 1961-06-14 1965-08-03 Rosen Alfred H High fidelity sound reproducer
US4354066A (en) * 1980-09-15 1982-10-12 Necoechea Robert W Rigid-diaphragm transducer with plural coils
EP0098895A1 (en) * 1980-09-15 1984-01-25 Robert Warren Necoechea Rigid diaphragm transducer with plural coils
US20020114214A1 (en) * 2001-01-26 2002-08-22 Hansen Kaj Borge Electroacoustic transducer
US20050031152A1 (en) * 2001-01-26 2005-02-10 Sonionkirk A/S Coil for an electroacoustic transducer
US7062063B2 (en) * 2001-01-26 2006-06-13 Sonion Horsens A/S Electroacoustic transducer
US20060215873A1 (en) * 2001-01-26 2006-09-28 Hansen Kaj B Electroacoustic transducer
US7376240B2 (en) * 2001-01-26 2008-05-20 Sonion Horsens A/S Coil for an electroacoustic transducer

Also Published As

Publication number Publication date
DE599805C (de) 1934-07-09
FR722913A (fr) 1932-03-30
NL33150C (en(2012))

Similar Documents

Publication Publication Date Title
JP7191348B2 (ja) スピーカーユニット及びスピーカー装置
US4276449A (en) Speaker or microphone having corrugated diaphragm with conductors thereon
JP3924918B2 (ja) 楕円型スピーカ
US10462577B2 (en) Ported cavity tweeter
US3955055A (en) Dynamic loudspeaker
US1934184A (en) Electrodynamic loud speaker
US2549091A (en) Diaphragm for electroacoustic transducers
KR101848735B1 (ko) 막대자석을 이용한 멀티 음역 재생이 가능한 스피커
US1973277A (en) Electroacoustic translating device
US2976373A (en) Omni-directional electro-acoustic converter of electro-magnetic type
US1631646A (en) Sound-reproducing apparatus
WO2023088123A1 (zh) 无源辐射器及音箱
JPH067711B2 (ja) スピ−カ
JPH0537599Y2 (en(2012))
US1866603A (en) Acoustic device
JPS5994995A (ja) 動電形スピ−カ
JPH1098789A (ja) スピーカ装置
US12262188B2 (en) Bone conduction loudspeaker
JPS6019419Y2 (ja) 複合型スピ−カ
JP2844846B2 (ja) ホーン形スピーカ
RU2746715C1 (ru) Плоский низкочастотный громкоговоритель
US1722805A (en) Sound radiator
JPH039434Y2 (en(2012))
JP3617154B2 (ja) スピーカ
JPS5912700A (ja) 複合型スピ−カ