DE548195C - Electrodynamic loudspeaker with a large sound radiator - Google Patents
Electrodynamic loudspeaker with a large sound radiatorInfo
- Publication number
- DE548195C DE548195C DER64584D DER0064584D DE548195C DE 548195 C DE548195 C DE 548195C DE R64584 D DER64584 D DE R64584D DE R0064584 D DER0064584 D DE R0064584D DE 548195 C DE548195 C DE 548195C
- Authority
- DE
- Germany
- Prior art keywords
- truncated cone
- membrane
- coil
- large sound
- electrodynamic loudspeaker
- 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
Links
- 230000005520 electrodynamics Effects 0.000 title claims description 3
- 239000012528 membrane Substances 0.000 description 16
- 230000000694 effects Effects 0.000 description 3
- 238000010276 construction Methods 0.000 description 2
- 239000003562 lightweight material Substances 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical group [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000013016 damping Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 239000010985 leather Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 230000003014 reinforcing effect Effects 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
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
- H04R9/025—Magnetic circuit
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R1/00—Details of transducers, loudspeakers or microphones
- H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
- H04R1/22—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired frequency characteristic only
- H04R1/24—Structural combinations of separate transducers or of two parts of the same transducer and responsive respectively to two or more frequency ranges
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R1/00—Details of transducers, loudspeakers or microphones
- H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
- H04R1/32—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only
- H04R1/34—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by using a single transducer with sound reflecting, diffracting, directing or guiding means
- H04R1/345—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by using a single transducer with sound reflecting, diffracting, directing or guiding means for loudspeakers
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R11/00—Transducers of moving-armature or moving-core type
- H04R11/02—Loudspeakers
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- 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
- H04R7/122—Non-planar diaphragms or cones comprising a plurality of sections or layers
-
- 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
- H04R7/20—Securing diaphragm or cone resiliently to support by flexible material, springs, cords, or strands
-
- 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
-
- 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
- H04R9/041—Centering
- H04R9/042—Centering by pressurised air
-
- 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
- H04R9/045—Mounting
-
- 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
- H04R9/063—Loudspeakers using a plurality of acoustic drivers
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- Health & Medical Sciences (AREA)
- Otolaryngology (AREA)
- Multimedia (AREA)
- Electromagnetism (AREA)
- Audible-Bandwidth Dynamoelectric Transducers Other Than Pickups (AREA)
- Diaphragms For Electromechanical Transducers (AREA)
- Electrostatic, Electromagnetic, Magneto- Strictive, And Variable-Resistance Transducers (AREA)
- Electromechanical Clocks (AREA)
Description
Die Erfindung bezieht sich auf einen Lautsprecher mit großflächigem Schallstrahler.The invention relates to a loudspeaker with a large-area sound emitter.
Man hat gefunden, daß- für die Umsetzung elektrischer Wechselströme in Schallschwingungen die konische Form einer Membran Vorteile bietet, und hat demgemäß schon frühzeitig derartige Membranen für Telephone benutzt, die man als flache Schalen oder flache Kegel ausbildete und z. B. auf einem Elektromagnetanker frei befestigte. Auch für Trichterlautsprecher hat man diese kleinen Membranen unter Nachahmung der Telephonkonstruktionen gebraucht, z. B. auch in der Weise, daß man sie am Rande mit einer dynamisch wirkenden Spule versah, die in ein Magnetfeld tauchte.It has been found that - for the conversion of electrical alternating currents into sound vibrations the conical shape of a membrane offers advantages, and accordingly has early Such membranes used for telephones, which were designed as flat shells or flat cones and z. B. on one Electromagnet armature freely attached. These small ones are also available for funnel speakers Membranes used to imitate the telephone constructions, z. B. also in the Way that one provided it at the edge with a dynamically acting coil, which in a magnetic field emerged.
Für trichterlose Lautsprecher, welche an sich wegen des Fortfalls der äußeren Schallleitmittel für eine klangschönere WiedergabeFor loudspeakers without funnels, which in themselves because of the omission of the external sound conducting means for a better sound reproduction
ao geeignet sind, haben die großflächigen ebenen Membranen den Nachteil der Klangverzerrung, die durch ungleichmäßige Teilschwingungen innerhalb der Membranfläche hervorgerufen wird. Auch die für solche Lautspreeher bisher benutzten Kegelmembrankonstruktionen sind hiervon nicht frei. Sie bildeten einfach eine Vergrößerung der entsprechenden Kleinmembranen für Telephone, ohne daß dabei beachtet wurde, welche Faktoren die wünschenswerte Eigenschaft der Membran bedingen, als Ganzes bis zu verhältnismäßig hohen Frequenzen zu schwingen, um so zu möglichst reinen Schwingungen zu gelangen.ao are suitable, the large flat membranes have the disadvantage of sound distortion, caused by uneven partial vibrations within the membrane surface will. Also the cone diaphragm constructions previously used for such loudspeakers are not exempt from this. They simply formed an enlargement of the corresponding Small diaphragms for telephones, without considering which factors the desirable property of the membrane condition, as a whole up to relatively to vibrate at high frequencies in order to achieve vibrations that are as pure as possible.
Gemäß vorliegender Erfindung wird die verzerrungsfreie Wiedergabe weitgehend erreicht, indem dem großflächigen Schallstrahler die neue Form des beiderseits offenen abgestumpften Kegels gegeben wird, der dadurch zu einem elektrodynamischen Lautsprecher ausgebildet wird, daß das schmale Ende mit einer in ein ringförmiges Magnetfeld tauchenden Spule versehen wird. Es hat sich gezeigt, daß man dem Kegelstumpf auch bei Herstellung aus leichtem Material leicht eine Form geben kann, die ihm die Eigenschaft als Kolbenschwinger sichert. Um Störungen des Schwingungsvorganges zu verhindern, wird der Kegelstumpf am Basisende durch äußerst biegsame Glieder aufgehängt und am schmalen Ende durch eine leichte federnde Abspannung geführt. Da dieses Ende offen ist, können sich auch keine störenden Luftpolster bilden.According to the present invention, the distortion-free reproduction is largely achieved, by giving the large-area sound emitter the new shape of the truncated, open on both sides Cone is given, which is formed into an electrodynamic loudspeaker that the narrow end is provided with a coil immersed in an annular magnetic field. It has shown that the truncated cone can easily be made from lightweight material Can give shape that secures it the property as a piston oscillator. To disturbances To prevent the oscillation process, the truncated cone is suspended at the base end by extremely flexible links and on the the narrow end is guided through a light, springy bracing. Because this end is open no annoying air cushions can form.
Man hätte an sich vielleicht erwarten können, daß der Übergang von dem Kegel zum Kegelstumpf infolge des Fortfalles der steiferen Kegelspitze eine Erhöhung der Formsteifigkeit nicht hätte bringen können, so daß sich der Kegelstumpf zur Ausführung von Kolbenschwingungen auch nicht besserPerhaps one could have expected that the transition from the cone to the Truncated cone due to the elimination of the stiffer cone tip an increase in the dimensional stiffness could not have brought, so that the truncated cone for the execution of piston vibrations is no better
eignen würde. Die Versuche haben aber ergeben, daß unter Innehaltung gewisser Dimensionierungen der Kegelstumpf mit dem am schmalen Ende aufgesetzten Spulentragring bei offener Form bis zu verhältnismäßig hohen Schwingungen tatsächlich die beschriebene Wirkung der Klangverbesserung hat.would suit. The tests have shown that while maintaining certain dimensions the truncated cone with the coil support ring attached to the narrow end is up to relatively high when the shape is open high vibrations actually has the described effect of improving the sound.
Die Erfindung ist auf der Zeichnung in vier Figuren dargestellt,
ίο Fig. ι ist ein Längsschnitt.The invention is shown in the drawing in four figures,
ίο Fig. ι is a longitudinal section.
Fig. 2 und 3 zeigen Teile der Fig. ι in größerem Maßstabe, undFig. 2 and 3 show parts of Fig. Ι in larger scale, and
Fig. 4 zeigt die Anordnung gemäß Fig. 3 schaubildlich.FIG. 4 shows the arrangement according to FIG. 3 graphically.
ι ist eine Membran von konischer Form, die an einem Ring 2 mit Hilfe eines Ringes 3 aus Seide, Gummi, dünnem Leder o. dgl. befestigt ist. Sie besteht aus Papier oder einem ähnlichen leichten Material, das steif ζσ genug ist, um als Ganzes zu schwingen. Am inneren Ende 4 ist sie als Zylinder mit Verstärkungsringen 5 und 6 ausgebildet. Die Betätigung der Membran erfolgt durch eine Spule 7, die den Verstärkungsring 5 umgibt. In dem Luftraum 8 ist die Spule 7 zwischen den Polstücken 9 und 10 angeordnet. Das innere Polstück ist von einer Spule 21 umgeben, durch die Gleichstrom geschickt wird, um in dem Luftraum 8 ein starkes magnetisches Feld zu erzeugen.ι is a membrane of conical shape, which is attached to a ring 2 by means of a ring 3 made of silk, rubber, thin leather or the like. It consists of paper or a similar lightweight material that is stiff ζσ enough to vibrate as a whole. At the inner end 4 it is designed as a cylinder with reinforcing rings 5 and 6. The membrane is actuated by a coil 7 which surrounds the reinforcement ring 5. In the air space 8, the coil 7 is arranged between the pole pieces 9 and 10. The inner pole piece is surrounded by a coil 21 through which direct current is sent in order to generate a strong magnetic field in the air space 8.
Wenn der Spule 7 veränderliche Ströme zugeführt werden, schwingt die Membran als Ganzes. Um die seitliche Verschiebung der Spule 7 im Luftraum 8 zu verhindern, ist das innere Polstück 9 in der Mitte mit einem Ansatz 20 versehen, an dem ein Haltering 11 angeschraubt ist. Dieser enthält eine Anzahl federnder Arme 13, die durch radiale Verbindungen 14 aus Bindfaden oder Draht mit dem zylindrischen Teil der Membran verbunden sind.When variable currents are supplied to the coil 7, the diaphragm vibrates as Whole. In order to prevent the lateral displacement of the coil 7 in the air space 8, this is inner pole piece 9 is provided in the middle with an extension 20 on which a retaining ring 11 is screwed on. This contains a number of resilient arms 13 by radial Connections 14 of string or wire connected to the cylindrical part of the membrane are.
Der Ring 2 ist an dem Polstück 10 durch Stützen 15 und der magnetische Aufbau an der Grundplatte 17 durch Stützen 16 befestigt. Bei einem Durchmesser der Membran von etwa 14 cm hatte eine solche Papiermembran eine natürliche Frequenz von 50; jedoch sind noch gute "Resxiltate bis zu Frequenzen von 200 erzielt worden, besonders wenn für entsprechende Dämpfung gesorgt war.The ring 2 is attached to the pole piece 10 by supports 15 and the magnetic structure the base plate 17 is fixed by supports 16. Such a paper membrane had a diameter of the membrane of about 14 cm a natural frequency of 50; however, there are still good "resxiltates" up to frequencies of 200 has been achieved, especially when appropriate damping was provided.
Beide Seiten der Membran 1 sind der Luft ausgesetzt, und zwar hat die Luft zu der Vorder- und Hinterseite der Membran um den Tragring 2 freien Zutritt, ohne eine merkliche Kompression zu erfahren. Hierdurch würde sich eine Schwächung der niedrigen Töne ergeben. Wenn jedoch der Weg zwischen der Vorder- und Rückseite der Membran auf etwa ein Viertel Wellenlänge oder mehr verlängert wird, wird dieser Umlauf verhindert und eine gute Strahlung erreicht. Diese Wirkung erzielt man, indem man die Membran mit einer Wand 18 umgibt, die den Umlauf verhindert. Man kann dieselbe Wirkung auch erzielen, wenn man die Membran nebst ihrem Antrieb in einem Gehäuse unterbringt.Both sides of the membrane 1 are exposed to the air, namely the air has to the front and back of the membrane around the support ring 2 free access without a noticeable Experience compression. This would weaken the lower tones. However, if the path between the front and back of the membrane is extended to about a quarter wavelength or more this circulation is prevented and good radiation is achieved. Achieved this effect by surrounding the membrane with a wall 18 which prevents circulation. The same effect can also be achieved if the membrane and its drive are accommodated in a housing.
Der eben besprochene Lautsprecher verlangt zur Erregung der Spule 21 einen beträchtlichen Strom. Es ist manchmal wünschenswert, das Feld durch gleichgerichtete Wechselströme zu erzeugen. Um in diesem Falle eine Modulierung der Töne und die Erzeugung von Tönen, die Harmonische der Gleichrichterfrequenz sind, zu verhindern, wird das Ende 19 der Feldspule mit einem schweren Kupferring versehen.The loudspeaker just discussed requires a considerable amount to excite the coil 21 Current. It is sometimes desirable to generate the field using rectified alternating currents. To be in this Case a modulation of the tones and the generation of tones, the harmonics of the Rectifier frequency are to prevent, the end 19 of the field coil with a heavy Provided with a copper ring.
Claims (2)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US1483A US1707617A (en) | 1925-01-09 | 1925-01-09 | Sound-reproducing apparatus |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| DE548195C true DE548195C (en) | 1932-04-08 |
Family
ID=21696234
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DER64584D Expired DE548195C (en) | 1925-01-09 | 1925-06-13 | Electrodynamic loudspeaker with a large sound radiator |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US1707617A (en) |
| BE (2) | BE356544A (en) |
| DE (1) | DE548195C (en) |
| FR (9) | FR610959A (en) |
| GB (2) | GB245796A (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2498825A (en) * | 1943-09-15 | 1950-02-28 | Hartford Nat Bank & Trust Comp | Moving coil transducer and enclosure |
| US2547565A (en) * | 1946-09-26 | 1951-04-03 | Wright Zimmerman Inc | Speaker having a tubular pot |
| US6639994B1 (en) | 2000-08-16 | 2003-10-28 | Jl Audio, Inc. | Loudspeaker having adjustable motor strength |
| FR2851115B1 (en) * | 2003-02-10 | 2008-01-25 | Patrick Hoffmann | ACOUSTIC TRANSDUCER GENERATING SOUND RADIATION BY COMPRESSION AND EXPANSION OF AIR MASS SITUATED BETWEEN A MOBILE MEMBRANE AND A FIXED SURFACE OR BETWEEN TWO MOBILE MEMBRANES |
| US8295536B2 (en) | 2010-03-31 | 2012-10-23 | Bose Corporation | Moving magnet levered loudspeaker |
| US8295537B2 (en) | 2010-03-31 | 2012-10-23 | Bose Corporation | Loudspeaker moment and torque balancing |
| CN102026067B (en) * | 2011-01-12 | 2013-07-24 | 常州声泰龙电子音响有限公司 | Loudspeaker and vibration part thereof |
| US9055370B2 (en) | 2012-08-31 | 2015-06-09 | Bose Corporation | Vibration-reducing passive radiators |
-
0
- BE BE331748D patent/BE331748A/xx unknown
- BE BE356544D patent/BE356544A/fr unknown
-
1925
- 1925-01-09 US US1483A patent/US1707617A/en not_active Expired - Lifetime
- 1925-06-13 DE DER64584D patent/DE548195C/en not_active Expired
-
1926
- 1926-01-07 FR FR610959D patent/FR610959A/en not_active Expired
- 1926-01-09 GB GB704/26A patent/GB245796A/en not_active Expired
-
1927
- 1927-11-30 GB GB32252/27A patent/GB310759A/en not_active Expired
-
1928
- 1928-07-11 FR FR35605D patent/FR35605E/en not_active Expired
- 1928-11-29 FR FR36325D patent/FR36325E/en not_active Expired
- 1928-12-01 FR FR36705D patent/FR36705E/en not_active Expired
-
1929
- 1929-02-16 FR FR37084D patent/FR37084E/en not_active Expired
- 1929-02-19 FR FR37086D patent/FR37086E/en not_active Expired
-
1933
- 1933-01-21 FR FR43362D patent/FR43362E/en not_active Expired
- 1933-04-26 FR FR43759D patent/FR43759E/en not_active Expired
-
1934
- 1934-12-27 FR FR46228D patent/FR46228E/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| FR35605E (en) | 1930-03-26 |
| BE331748A (en) | |
| GB245796A (en) | 1927-04-11 |
| FR36705E (en) | 1930-09-03 |
| GB310759A (en) | 1929-04-30 |
| FR36325E (en) | 1930-05-08 |
| FR43362E (en) | 1934-05-11 |
| FR37084E (en) | 1930-10-15 |
| BE356544A (en) | |
| FR37086E (en) | 1930-10-15 |
| FR43759E (en) | 1934-08-29 |
| US1707617A (en) | 1929-04-02 |
| FR610959A (en) | 1926-08-17 |
| FR46228E (en) | 1936-04-02 |
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