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Dynamic loudspeaker using wall as diaphragm

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Publication number
US3728497A
US3728497A US3728497DA US3728497A US 3728497 A US3728497 A US 3728497A US 3728497D A US3728497D A US 3728497DA US 3728497 A US3728497 A US 3728497A
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Prior art keywords
transducer
portion
member
damper
pillar
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Expired - Lifetime
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A Komatsu
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A Komatsu
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04RLOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R9/00Transducers of moving-coil, moving-strip, or moving-wire type
    • H04R9/06Loudspeakers
    • H04R9/066Loudspeakers using the principle of inertia

Abstract

A hollow pillar portion is connected to the damper or casing of a transducer to mount the transducer onto a support on board member by a screw which passes through the hollow pillar portion. The hollow pillar portion enables both the low and high frequency characteristics to be maintained and enables the transducer to be affixed to the board member without rotation of the transducer.

Description

United States Patent Komatsu 51 Apr. 17 1973 [54] DYNAMIC LOUDSPEAKER USING 3,636,281 1/1972 Cozart ..179/l8l w WALL AS DIAPHRAGM 3,609,253 9/1971 Ashworth ..179/115.5 R

[76] Inventor: Akira Komatsu, 2382 Oizumigakuemcho, Tokyo, Japan Prlmary Examiner-Kathleen H. Claffy Assistant Examiner-Thomas L. Kundert [22] Filed June 1971 Attorney-Pierce, Schefiler & Parker [21] Appl. No.: 157,395

[57] ABSTRACT [30] F reign Application Priority ata A hollow pillar portion is connected to the damper or July 6, 1970 Japan ..45 67265 casing a transducer the transduFer mm a support on board member by a screw whlch passes 52 us. c1. ..179/1s1 w, 179/115.5 R through the hollow P P The Pi"ar 51 1111. C1. ..H04r 9/04 Portion enables both the low and high frequency [58] Field of Search 179/181 w, 115.5 R; h r ri to be n in n enables h r n 310/15, 27 1 ducer to be afiixed to the board member without rotation of the transducer. [56] References Cited 3 Claims, 3 Drawing Figures UNITED STATES PATENTS 3,366,749 l/1968 Ries ..l79/115.5 R

1 2b 1 5 ,g 3b v 20 Q (1 6 2 "Y -:\7Q

I I --7 I i v B LLN DYNAMIC LOUDSPEAKER USING WALL AS DIAPHRAGM This invention relates to a dynamic transducer for converting electrical energy into sound energy, and is particularly concerned with an audio transducer which will be mounted on a board member in a room such as a wall or ceiling.

About the above transducer, the construction which determines the manner of mounting is important. However, as far as I know, various heretofore known constructions do not permit satisfactory mounting without an accompanying sacrifice of performance in the transducer. For example, in a type of transducer wherein a wood screw is attached to a damper or a diaphragm as shown in US. Pat. Ser. No. 3,430,007, the damper or the diaphragm must be sufficiently strong and stiff so as to withstand the torque necessary for screwing the wood screw into a board member in the room. But, it is undesirable to increase the strength and stiffness of the damper since the efficiency of the transducer is reduced especially in the low frequency zone. Further, as the type of transducer above mentioned is mounted on a board by rotation of the transducer, lead wires connected to the terminals are often twisted and entangled.

The damper may be one with suitable stiffness, if the transducer is constructed so as to be screwed into a base plate previously fixed on a wall. The transducer shown in U.S. Pat. Ser. No. 3,366,749 is one of this type. But, this type of transducer must be also mounted by rotation.

Transducers can be mounted without rotation, if a flange plate is provided thereon as a member for mounting. However, this type of transducer has low efficiency especially in the high frequency zone owing to a spring action caused by the path through which vibration is transmitted. When the wall is one with considerable thickness and stiffness, the above spring action is suppressed. Accordingly, the transducer of the last mentioned type may be used satisfactorily in particular cases where the spring action is suppressed by the nature of the wall or the like.

The principal object of the present invention is to provide an improved dynamic transducer in which the above explained difficulties are overcome.

According to the present invention, there is provided a dynamic transducer characterized in that a hollow pillar portion is connected to the damper of the voice coil, and the hollow pillar portion passes through a hole in the center pole of the magnet of the transducer, the internal diameter of the hole in the magnet through which the hollow pillar portion passes being larger than the external diameter of the hollow pillar portion, and a screw for mounting the transducer on a board member in the room being admitted through and spaced from the hollow pillar portion.

Other objects and advantages of the present invention will be apparent from the following description of the accompanying drawings in which:

FIG. 1 is a longitudinally sectioned view of a dynamic transducer according to the present invention;

FIG. 2 is a longitudinally sectioned view of another dynamic transducer according to the present invention;

FIG. 3 is a longitudinally sectioned view of still another dynamic transducer according to the present invention.

The transducer shown in FIG. 1 is mounted on a board member I. The magnet of this transducer is composed of a yoke 3 and a permanent magnet 4. The plate portion and the center pole portion of the magnet are shown by the numerals 3a, 3b respectively. The magnet is provided with a hole 30 which passes through the center pole 3b of the magnet.

The damper of the transducer comprises a boss portion 2a which engages with the board member 1, a supporting portion 2b for a voice coil 5, a spring portion 20 and a portion 2d which engages with the magnet. The boss portion 2a is provided with a center hole which a wood screw 6 passes through. The portion 2d is engaged with and fixed to the outer peripheral surface of the plate portion 3a of the magnet, thus, determining the position of the voice coil 5 in the air gap of the magnet.

A case 7 with a central pillar or cylindrical portion 7a is provided for enclosing the above mentioned various parts. The pillar portion 7a passes through the hole 3c of the center pole 3b. There is a sufficient space between the center pole 3b and the pillar portion 7a to avoid any mutual contact therebetween. The pillar portion 7a is hollow and a wood screw 6 passes freely through this portion 7a and the hole of the boss portion 2a of the damper 2. The hollow pillar portion 7a of the case 7 is fixed to the damper 2. In this modification the case 7 does not contact with the magnet and vibrates together the board member 1.

The transducer is mounted on the board member 1 by the wood screw 6 following a process wherein any turning of the transducer and stresses on the vibrating spring portion 20 of the damper 2 are eliminated.

The damper 2 can be made as a single unit thus improving the low frequency zone characteristics, and furthermore, the boss portion 2a of the damper 2 having a small area the board member 1 at its front end thus, improving high frequency zone characteristics.

The construction shown in FIG. 1 can be modified as shown in FIG. 2. In the case of the transducer shown in FIG. 2, the damper 2 is formed as a part of the case 7 and arranged remote from the inner board member 1.

' Between the end of the pillar portion 7a and the yoke 3,

a member 8 is disposed as a dust cover. This member 8 may be modified to one which acts as a damper. Then, the transducer becomes a type wherein dampers are disposed on both sides. The transducer is mounted on a board member 1 similarly to the transducer shown in FIG. 1. The voice coil 5 is arranged remote from the board member 1, but the performance of the transducer is the same as that of the transducer shown in FIG. 1.

The transducer shown in FIG. 3 is provided with a inner end plate 9 which covers the open end of the case. This type of transducer is the same with that shown in FIG. 1 except for the provision of the end plate 9.

What I claim is:

l. A dynamic transducer comprising a disc shaped damper member having a relatively thick hub portion having a central opening therethrough and a relatively thin outer portion, a voice coil mounted on an axially extending sleeve having one end thereof secured to said damper member, an annular magnetic assembly including an annular permanent magnet and an annular yoke portion providing an axially extending gap into which transmitting the attaching force through said pillar member and said hub portion.

2. A dynamic transducer as claimed in claim 1 and further comprising a casing and wherein said pilla member is attached to said casing.

3. A dynamic transducer as claimed in claim 1 wherein said pillar member isattached to the hub portion of said damper member.

Claims (3)

1. A dynamic transducer comprising a disc shaped damper member having a relatively thick hub portion having a central opening therethrough and a relatively thin outer portion, a voice coil mounted on an axially extending sleeve having one end thereof secured to said damper member, an annular magnetic assembly including an annular permanent magnet and an annular yoke portion providing an axially extending gap into which said voice coil extends, said magnetic assembly being secured to and supported by said outer portion of said damper member, a hollow pillar member one end of which extends from said hub portion through and spaced from the center of said annular magnetic assembly and having a hole therethrough in alignment with the central opening in said hub portion and a screw member extending through and spaced from said pillar member and said hub portion for attaching the transducer to a support, the head of the screw member transmitting the attaching force through said pillar member and said hub portion.
2. A dynamic transducer as claimed in claim 1 and further comprising a casing and wherein said pillar member is attached to said casing.
3. A dynamic transducer as claimed in claim 1 wherein said pillar member is attached to the hub portion of said damper member.
US3728497A 1970-07-06 1971-06-28 Dynamic loudspeaker using wall as diaphragm Expired - Lifetime US3728497A (en)

Priority Applications (1)

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JP6726570U JPS5221050Y1 (en) 1970-07-06 1970-07-06

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US3728497A Expired - Lifetime US3728497A (en) 1970-07-06 1971-06-28 Dynamic loudspeaker using wall as diaphragm

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JP (1) JPS5221050Y1 (en)
DE (1) DE2132018B2 (en)

Cited By (36)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4354067A (en) * 1978-05-17 1982-10-12 Bodysonic Kabushiki Kaisha Audio-band electromechanical vibration converter
US4392027A (en) * 1978-05-05 1983-07-05 Messerschmitt-Boelkow-Blohm Gesellschaft Mit Beschraenkter Haftung Method and apparatus for providing a uniform sound distribution in an aircraft cabin
US4495638A (en) * 1978-05-17 1985-01-22 Body Sonic Kabushiki Kaisha Audio-band electro-mechanical vibration converter
US4506117A (en) * 1981-12-22 1985-03-19 Multiphonie S.A. Electroacoustic transducer
DE3523973A1 (en) * 1984-07-10 1986-01-23 Pioneer Electronic Corp Electric vibration converter
WO1989000798A1 (en) * 1987-07-13 1989-01-26 Avm Hess, Inc. Sound transducer
US4926486A (en) * 1987-07-17 1990-05-15 Barsumian Bruce R Transducer assembly for automatic message system
US4951270A (en) * 1989-06-20 1990-08-21 Andrews Jay E Audio transducer apparatus
US5058173A (en) * 1990-01-05 1991-10-15 Ashworth William J Combination inertia type audio transducer and loudspeaker
US5335284A (en) * 1993-11-23 1994-08-02 Lemons James W Coneless, no-moving-parts speaker
US5546469A (en) * 1994-08-15 1996-08-13 Donahoe; Danny T. Sound transducer
US5706358A (en) * 1996-07-26 1998-01-06 Ashworth; William J. Magnetic audio transducer with hinged armature
US5793877A (en) * 1995-05-19 1998-08-11 Moonstone Technology Limited Through-window speaker/microphone
DE19818988A1 (en) * 1998-04-28 1999-11-11 Siemens Ag Electronic apparatus with electro-acoustic transducer e.g. for mobile telephone
US6151402A (en) * 1995-09-02 2000-11-21 New Transducers Limited Vibration transducers
US6519349B1 (en) 1995-09-02 2003-02-11 New Transducers Limited Loudspeaker
US20030048918A1 (en) * 2001-09-07 2003-03-13 Dillon Geoffrey M. Installing a high fidelity sound, voice paging, or music system by mounting an electrical to acoustic transducer inside a wall mounted gang box
US6751333B1 (en) 1995-09-02 2004-06-15 New Transducers Limited Inertial vibration transducers
US6792126B2 (en) * 1998-05-15 2004-09-14 Fujitsu Limited Information processing device and speaker unit applicable thereto
US6904154B2 (en) 1995-09-02 2005-06-07 New Transducers Limited Acoustic device
US20050184607A1 (en) * 2004-02-20 2005-08-25 Yuichi Nakajima Exciter for directly vibrating board
US20050201571A1 (en) * 2004-03-12 2005-09-15 Shell Shocked Sound, Inc. Acoustic bracket system
US20050207609A1 (en) * 2004-02-19 2005-09-22 Oser R B Transducer for tactile applications and apparatus incorporating transducers
US6965679B1 (en) * 2000-10-17 2005-11-15 Alejandro Jose Pedro Lopez Bosio Equalizable electro-acoustic device used in commercial panels and method for converting said panels
US20060115107A1 (en) * 2004-11-24 2006-06-01 Vincent Stephen S Inertial voice type coil actuator
US20070025575A1 (en) * 2005-02-18 2007-02-01 So Sound Solutions Llc System and method for integrating transducers into body support structures
US7292702B2 (en) 2003-04-29 2007-11-06 Dimensional Communications, Inc. In-wall speaker system method and apparatus
US20080044042A1 (en) * 2006-08-18 2008-02-21 Wei Jia Liu Sonic transducer
US20080085029A1 (en) * 2003-04-29 2008-04-10 Hagman Paul N In-wall speaker system method and apparatus
US20090010468A1 (en) * 2004-02-19 2009-01-08 Richard Barry Oser Actuation of floor systems using mechanical and electro-active polymer transducers
DE202008017352U1 (en) 2008-07-03 2009-07-09 Preform Gmbh Adaptive noise generating device
US20100316236A1 (en) * 2009-06-11 2010-12-16 Snider Darin J Home Theater
DE102009048866A1 (en) 2009-08-27 2011-03-03 Bösnecker, Robert, Dr. Device for vibration stimulation of diaphragms or diaphragm-type materials showing frequencies in audio range of humans, has electrical change signal partly converted in mechanical motion, where converter possess hole or opening
US8358801B2 (en) 2007-02-12 2013-01-22 Robert Katz Magnetic circuit for electrodynamic moving voice coil actuators
WO2015024092A1 (en) * 2013-08-21 2015-02-26 Vista Acquisitions Inc. Audio systems for generating sound on personal watercraft and other recreational vehicles
US9025798B2 (en) 2010-06-09 2015-05-05 Stephen Saint Vincent Multi-coaxial transducers and methods

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA1007355A (en) * 1974-06-17 1977-03-22 Canadian General Electric Company Limited Ultrasonic transducer mounting and coupling assembly
JP4960752B2 (en) * 2007-04-24 2012-06-27 パナソニック株式会社 Bathroom interior Itaon output system
CN102498729B (en) 2009-09-09 2015-06-10 Ask工业股份公司 Shaker-type transducer with centering device

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3366749A (en) * 1964-04-09 1968-01-30 Allen Alan A Audio transducer
US3609253A (en) * 1968-05-03 1971-09-28 William J Ashworth Loudspeaker with improved voice coil suspension
US3636281A (en) * 1969-01-13 1972-01-18 Robert T Cozart Loudspeaker using wall as diaphragm

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3366749A (en) * 1964-04-09 1968-01-30 Allen Alan A Audio transducer
US3609253A (en) * 1968-05-03 1971-09-28 William J Ashworth Loudspeaker with improved voice coil suspension
US3636281A (en) * 1969-01-13 1972-01-18 Robert T Cozart Loudspeaker using wall as diaphragm

Cited By (54)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4392027A (en) * 1978-05-05 1983-07-05 Messerschmitt-Boelkow-Blohm Gesellschaft Mit Beschraenkter Haftung Method and apparatus for providing a uniform sound distribution in an aircraft cabin
US4354067A (en) * 1978-05-17 1982-10-12 Bodysonic Kabushiki Kaisha Audio-band electromechanical vibration converter
US4495638A (en) * 1978-05-17 1985-01-22 Body Sonic Kabushiki Kaisha Audio-band electro-mechanical vibration converter
US4506117A (en) * 1981-12-22 1985-03-19 Multiphonie S.A. Electroacoustic transducer
EP0083310B1 (en) * 1981-12-22 1987-03-18 Multiphonie S.A. Electro-acoustic transducer
DE3523973A1 (en) * 1984-07-10 1986-01-23 Pioneer Electronic Corp Electric vibration converter
US4914750A (en) * 1987-07-13 1990-04-03 Avm Hess, Inc. Sound transducer
WO1989000798A1 (en) * 1987-07-13 1989-01-26 Avm Hess, Inc. Sound transducer
US4926486A (en) * 1987-07-17 1990-05-15 Barsumian Bruce R Transducer assembly for automatic message system
US4951270A (en) * 1989-06-20 1990-08-21 Andrews Jay E Audio transducer apparatus
US5058173A (en) * 1990-01-05 1991-10-15 Ashworth William J Combination inertia type audio transducer and loudspeaker
US5335284A (en) * 1993-11-23 1994-08-02 Lemons James W Coneless, no-moving-parts speaker
US5546469A (en) * 1994-08-15 1996-08-13 Donahoe; Danny T. Sound transducer
US5793877A (en) * 1995-05-19 1998-08-11 Moonstone Technology Limited Through-window speaker/microphone
US6904154B2 (en) 1995-09-02 2005-06-07 New Transducers Limited Acoustic device
US7158647B2 (en) 1995-09-02 2007-01-02 New Transducers Limited Acoustic device
US6151402A (en) * 1995-09-02 2000-11-21 New Transducers Limited Vibration transducers
US6519349B1 (en) 1995-09-02 2003-02-11 New Transducers Limited Loudspeaker
US7194098B2 (en) 1995-09-02 2007-03-20 New Transducers Limited Acoustic device
US6751333B1 (en) 1995-09-02 2004-06-15 New Transducers Limited Inertial vibration transducers
US20050147273A1 (en) * 1995-09-02 2005-07-07 New Transducers Limited Acoustic device
US20060159293A1 (en) * 1995-09-02 2006-07-20 New Transducers Limited Acoustic device
US5706358A (en) * 1996-07-26 1998-01-06 Ashworth; William J. Magnetic audio transducer with hinged armature
DE19818988A1 (en) * 1998-04-28 1999-11-11 Siemens Ag Electronic apparatus with electro-acoustic transducer e.g. for mobile telephone
US6792126B2 (en) * 1998-05-15 2004-09-14 Fujitsu Limited Information processing device and speaker unit applicable thereto
US6965679B1 (en) * 2000-10-17 2005-11-15 Alejandro Jose Pedro Lopez Bosio Equalizable electro-acoustic device used in commercial panels and method for converting said panels
US20030048918A1 (en) * 2001-09-07 2003-03-13 Dillon Geoffrey M. Installing a high fidelity sound, voice paging, or music system by mounting an electrical to acoustic transducer inside a wall mounted gang box
US20080085029A1 (en) * 2003-04-29 2008-04-10 Hagman Paul N In-wall speaker system method and apparatus
US7292702B2 (en) 2003-04-29 2007-11-06 Dimensional Communications, Inc. In-wall speaker system method and apparatus
US20090010468A1 (en) * 2004-02-19 2009-01-08 Richard Barry Oser Actuation of floor systems using mechanical and electro-active polymer transducers
US20050207609A1 (en) * 2004-02-19 2005-09-22 Oser R B Transducer for tactile applications and apparatus incorporating transducers
US8761417B2 (en) 2004-02-19 2014-06-24 So Sound Solutions, Llc Tactile stimulation using musical tonal frequencies
US8077884B2 (en) 2004-02-19 2011-12-13 So Sound Solutions, Llc Actuation of floor systems using mechanical and electro-active polymer transducers
US7418108B2 (en) 2004-02-19 2008-08-26 So Sound Solutions, Llc Transducer for tactile applications and apparatus incorporating transducers
US7030522B2 (en) * 2004-02-20 2006-04-18 Fujitsu Ten Limited Exciter for directly vibrating board
US20050184607A1 (en) * 2004-02-20 2005-08-25 Yuichi Nakajima Exciter for directly vibrating board
US20050201571A1 (en) * 2004-03-12 2005-09-15 Shell Shocked Sound, Inc. Acoustic bracket system
US7636447B2 (en) * 2004-03-12 2009-12-22 Multi Service Corporation Acoustic bracket system
US7386144B2 (en) 2004-11-24 2008-06-10 Revolution Acoustics, Ltd. Inertial voice type coil actuator
US20060115107A1 (en) * 2004-11-24 2006-06-01 Vincent Stephen S Inertial voice type coil actuator
US8617089B2 (en) 2005-02-18 2013-12-31 So Sound Solutions Llc Inducing tactile stimulation of musical tonal frequencies
US20070025575A1 (en) * 2005-02-18 2007-02-01 So Sound Solutions Llc System and method for integrating transducers into body support structures
US7981064B2 (en) 2005-02-18 2011-07-19 So Sound Solutions, Llc System and method for integrating transducers into body support structures
US20080044042A1 (en) * 2006-08-18 2008-02-21 Wei Jia Liu Sonic transducer
US8358801B2 (en) 2007-02-12 2013-01-22 Robert Katz Magnetic circuit for electrodynamic moving voice coil actuators
US20110211721A1 (en) * 2008-07-03 2011-09-01 Preform Gmbh Adaptive noise generating device
DE202008017352U1 (en) 2008-07-03 2009-07-09 Preform Gmbh Adaptive noise generating device
US8611576B2 (en) 2008-07-03 2013-12-17 Preform Gmbh Adaptive noise generating device
US20100316236A1 (en) * 2009-06-11 2010-12-16 Snider Darin J Home Theater
US8340327B2 (en) * 2009-06-11 2012-12-25 Magna International Inc. Home theater
DE102009048866A1 (en) 2009-08-27 2011-03-03 Bösnecker, Robert, Dr. Device for vibration stimulation of diaphragms or diaphragm-type materials showing frequencies in audio range of humans, has electrical change signal partly converted in mechanical motion, where converter possess hole or opening
US9025798B2 (en) 2010-06-09 2015-05-05 Stephen Saint Vincent Multi-coaxial transducers and methods
WO2015024092A1 (en) * 2013-08-21 2015-02-26 Vista Acquisitions Inc. Audio systems for generating sound on personal watercraft and other recreational vehicles
US9774936B2 (en) 2013-08-21 2017-09-26 Vista Acquisitions Inc. Audio systems for generating sound on personal watercraft and other recreational vehicles

Also Published As

Publication number Publication date Type
DE2132018A1 (en) 1972-01-20 application
JPS5221050Y1 (en) 1977-05-14 grant
DE2132018B2 (en) 1972-11-02 application

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