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Publication numberUS3728497 A
Publication typeGrant
Publication dateApr 17, 1973
Filing dateJun 28, 1971
Priority dateJul 6, 1970
Also published asDE2132018A1, DE2132018B2
Publication numberUS 3728497 A, US 3728497A, US-A-3728497, US3728497 A, US3728497A
InventorsKomatsu A
Original AssigneeKomatsu A
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Dynamic loudspeaker using wall as diaphragm
US 3728497 A
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.
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Description  (OCR text may contain errors)

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.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US3366749 *Apr 9, 1964Jan 30, 1968Allen Alan AAudio transducer
US3609253 *May 3, 1968Sep 28, 1971Ashworth William JLoudspeaker with improved voice coil suspension
US3636281 *Jan 13, 1969Jan 18, 1972Cozart Robert TLoudspeaker using wall as diaphragm
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4354067 *Mar 30, 1979Oct 12, 1982Bodysonic Kabushiki KaishaAudio-band electromechanical vibration converter
US4392027 *Jun 26, 1981Jul 5, 1983Messerschmitt-Boelkow-Blohm Gesellschaft Mit Beschraenkter HaftungMethod and apparatus for providing a uniform sound distribution in an aircraft cabin
US4495638 *Feb 23, 1981Jan 22, 1985Body Sonic Kabushiki KaishaAudio-band electro-mechanical vibration converter
US4506117 *Dec 15, 1982Mar 19, 1985Multiphonie S.A.Electroacoustic transducer
US4914750 *Jul 13, 1987Apr 3, 1990Avm Hess, Inc.Sound transducer
US4926486 *Dec 19, 1988May 15, 1990Barsumian Bruce RTransducer assembly for automatic message system
US4951270 *Jun 20, 1989Aug 21, 1990Andrews Jay EAudio transducer apparatus
US5058173 *Jan 5, 1990Oct 15, 1991Ashworth William JCombination inertia type audio transducer and loudspeaker
US5335284 *Nov 23, 1993Aug 2, 1994Lemons James WConeless, no-moving-parts speaker
US5546469 *Aug 15, 1994Aug 13, 1996Donahoe; Danny T.Sound transducer
US5706358 *Jul 26, 1996Jan 6, 1998Ashworth; William J.Magnetic audio transducer with hinged armature
US5793877 *May 19, 1995Aug 11, 1998Moonstone Technology LimitedSystem for radiating sound from a movable member
US6151402 *Sep 2, 1996Nov 21, 2000New Transducers LimitedVibration transducers
US6519349May 12, 2000Feb 11, 2003New Transducers LimitedLoudspeaker
US6751333Oct 25, 2000Jun 15, 2004New Transducers LimitedInertial vibration transducers
US6792126 *Sep 10, 1998Sep 14, 2004Fujitsu LimitedInformation processing device and speaker unit applicable thereto
US6904154Oct 18, 2001Jun 7, 2005New Transducers LimitedAcoustic device
US6965679 *Oct 17, 2000Nov 15, 2005Alejandro Jose Pedro Lopez BosioEqualizable electro-acoustic device used in commercial panels and method for converting said panels
US7030522 *Feb 2, 2005Apr 18, 2006Fujitsu Ten LimitedExciter for directly vibrating board
US7158647Mar 7, 2005Jan 2, 2007New Transducers LimitedAcoustic device
US7194098Mar 7, 2005Mar 20, 2007New Transducers LimitedAcoustic device
US7292702Apr 28, 2004Nov 6, 2007Dimensional Communications, Inc.In-wall speaker system method and apparatus
US7386144Nov 24, 2004Jun 10, 2008Revolution Acoustics, Ltd.Inertial voice type coil actuator
US7418108Feb 18, 2005Aug 26, 2008So Sound Solutions, LlcTransducer for tactile applications and apparatus incorporating transducers
US7636447 *Mar 10, 2005Dec 22, 2009Multi Service CorporationAcoustic bracket system
US7981064Aug 9, 2006Jul 19, 2011So Sound Solutions, LlcSystem and method for integrating transducers into body support structures
US8077884Jun 13, 2008Dec 13, 2011So Sound Solutions, LlcActuation of floor systems using mechanical and electro-active polymer transducers
US8340327 *Jun 9, 2010Dec 25, 2012Magna International Inc.Home theater
US8358801Feb 8, 2008Jan 22, 2013Robert KatzMagnetic circuit for electrodynamic moving voice coil actuators
US8611576Jun 24, 2009Dec 17, 2013Preform GmbhAdaptive noise generating device
US8617089Jun 29, 2011Dec 31, 2013So Sound Solutions LlcInducing tactile stimulation of musical tonal frequencies
US8761417Dec 9, 2011Jun 24, 2014So Sound Solutions, LlcTactile stimulation using musical tonal frequencies
US20100316236 *Jun 9, 2010Dec 16, 2010Snider Darin JHome Theater
DE3523973A1 *Jul 4, 1985Jan 23, 1986Pioneer Electronic CorpElektro-schwingungswandler
DE19818988A1 *Apr 28, 1998Nov 11, 1999Siemens AgElectronic apparatus with electro-acoustic transducer e.g. for mobile telephone
DE102009048866A1Aug 27, 2009Mar 3, 2011Bösnecker, 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
DE202008017352U1Jul 3, 2008Jul 9, 2009Preform GmbhAdaptive Rauscherzeugungsvorrichtung
EP0083310A1 *Dec 21, 1982Jul 6, 1983Multiphonie S.A.Electro-acoustic transducer
WO1989000798A1 *Aug 7, 1987Jan 26, 1989Avm Hess IncSound transducer
U.S. Classification381/392, 381/152, 381/419
International ClassificationH04R1/00, H04R1/02, H04R9/06
Cooperative ClassificationH04R9/066
European ClassificationH04R9/06B