|Title of Invention||
TRANS DUCER-ACOUSTIC TYPE
|Abstract||The invention in general relates to a Transducer devioe-Aooustio Type, to reproduce sound exactly in accordance to the input centric signal. This invention provides a transducer device having the characteristics of small size» light weight and pure quality of sound with zero coloration. This transducer device consists of electro mechanical apparatus of magnetic type or piezo electric type to convert electric signal to mechanical vibration and diaphragm, of type simple, composite, piezo electric or any of commotions to convert the mechanical vibrations to sound. The magnetic type consists of the voice coil which moves in a uniform magnetic field created by the magnetic apparatus according to the current flowing through it. lens voice coil is attached to the diaphragm to convert the vibrations created in it into sound. But in piezoelectric apparatus consists of a thin layer of piezo-electric crystal attached to a metal plate or sandwiched between two metal plates shrinks and expend when the electric signal is fed to the crystal and thus creating vibrations which transferred to the diaphragm attached to it and convert it into sound. The enclosure made from hard material plastic like Teflon and metals like aluminum and other is provided to enclose the rear surface of the diaphragm and houses the electro-mechanical apparatus. This enclosure does not absorb the vibrations from the diaphragm resting on it and has adequate provisions for inlet of the wires carrying electric signal to apparatus. This invention completely eliminates any coloration due to reflected Mind waves and enclosure resonance because it is an airtight arrangement and has a valve to vaccines it and to retain the vacuum towards the rear twice of the diaphragm.|
OBJECT OF THE INVEKTION
This particular Invention Is regarding ellnnfnating 'carnet coloration' a phenomenon with audio speakers, it consists of a speedily designed diaphragm made from soft materials Uri rubber or soft P.V.C and In the case of composite diaphragms they are made both from rubber and hard materials Juice Teflon. An electroHTiechanicEA appardkus to overt doctorial signers Into vibrations. A presto electric diaphragm Is used to reproduce high frequency sounds. Mainly a cabinet Is made to enclose the rear surface of the daphragrn lich Is vaccinated. en vacancies the diaphragm which Is made of a soft material either In part or full defames and settles In an equilibrium position. Then It Is set to vibrate according to the electrical signal by electromechanical apparatus thus prodded sound
As there Is no material sedum or air towards the rear surface of the diaphragm and as sound cannot be created In or travel through vacuum no sound vexes are emitted Into the cabinet thus completely denudating the problem of cabinet adoration'.
BACIOSWOUNP OF IKVENTIOW;-
Any speaker unit consists of one or prior drivers and an end sure. Every driver has three rib n parts namely:
Diaphragm Vice cod Magnetic apparatus
The vodka cilia vibrates according to the electrical sigils, alarm the uniform margined field created by the magnet apparatus and vibrates the daphragrn along vat It creating sound.
Any diaphragm has to have tm surfaces and sound way emptied from the front surface are Idol degree out of phase from the sound vexes emitted from the rear surface. both surfaces are left free to atmosphere the sound tees from either surfaces destructively Interfere thus producing wrong and waning or very poor quality of sound.
That is the reason Way an enclosure is made for the rear surface of the diaphragm so that they don’t Interfere. But here arises a new position. The sound vitiates sifted from the rear surface of the diaphragm get reflected of the enclosure and collide v4th diaphragm and being mecfianical ayes exert force on it.
Simply sealing the sound waves from the rear surface of the diaphragm cause air stiffness in the enclosure.
Actually the capering vibrates according to the force created in the vice coil due to the current flog along it. Len the reflected waves from the enclosure collude the diaphragm the force exerted by them interacts the force from the voice cal thus producing cabinet coloration'.
Due to the phenomenon of 'carnet coloration' any sepia err cannot just produce the frequency of sound as dictated by the signal but also produces another distortion frequency.
The supplementary sound waves belt of Niger frequency comprorrises the clarity of the sound heard.
This particular transducer consists mainly of three parts. Namely
Electro -Mechanical Apparatus and
Air tight vacounidsed enclosure.
Parts 1 and 2 vary in their design, structure and composition according to the particular use of the transducer.
Di|)hra9n : The diaphragm used in this particular apparatus can be of three different types. Namely :-
Simple Diapers : A diaphragrn made from a soft material rubber or soft P.V.C (Poly Vinyl Chloride) with hi Posen’s ratio and low youn8;s and shear module that grossly, inspire of some in'egularities lolls ill a dome.
Composite Diaphra^n: This diaphragm consists of two parts.
The center part is made from a hard-neat plastic material Teflon (polymer) or some lightwdght metal. This part of the composite also incorporates in It the voice CHOP of the magnetic type of electro Mschasilcai apparatus if used.
It can have a flat or cone shaped profile.
The peripheral rim part of the composite diaphragm is made from soft materials used in the case of simple one. It tail the siege of a hollow truncated cane,
Piezo-Bectiic Diaphragm : This type of dteiphragn consists of a thin layer of pies-electric crystal attached to a metal plate or sandvtrfched between two metal plates. If this type of diaphragm is used then there is no recjuircment for dectro-MadharAcak spurts as it can itself respond to electrical sfgials and produce
vexations and thus sound Additionally a diaphragm Which Is a combination of herein above types can sago be used
It Is the part traditionally found in other transducers that converts electrical signals into median cad vibrations.
It can be principally of two types namely :-
Magnetic lip : This type consists of magnetic apparatus and a voice chop. The magnetic apparatus creates a uniform magnetic filed along Vichy the cool rowels according to the current gloving along It. The votes camp being attached to the diaphragm transfers the vibrations created In to the dlaphragrt thus creating sound.
Piesso-etectric Type : This type consists of a thin layer of pi€ZD-electr1c crystal attached to a metal plate or sandwiched between two mobs plates en electric signal is fed to the crystal It shr1nl
The enclosure or carnet encloses the rear surface of the diaphragm and houses the electro mechanical £q3paratus. it has an air-tight arrangement and a valve to accurate It and to retain the vacuum. The cabinet Is made from a very hard materials as It should not absorb vibrations from the cRaphragm resting on It. it also prcMdes Inlet for the rues carrying electrical signal to the transducer.
Vein the transducer is being evacuated, the soft part of simple or composite diaphragm ever Is In use deform Into a near flat dome of very less
curvature or a truncated cone of very less heft respectively due to the Immune air pressure acting on the diaphragm, en the transducer is vaccinated to required extent the diaphragm settles at an equilibrium position ere external force due to air-pressure is equal to the internal forces developed in the diaphragm due to deformation (force due to shear and oppressive strain).
This type of set-up greatly reduces the mechanical impedance of tie diaphragm Wine compared to a totally plastic diaphragm (material property plastic or elastic) used under these conditions.
A pizza-electric diaphragm is used to produce hi frequerKy sound displacement of the diaphragm is necessary during operation, making taw effect of its high mechanical impedance tolerable.
leno the electrical signal is fed to the electro-mechanical apparatus or directly to the diaphragms in the case of pie-electric diaphragrn, vibrations are created in the diaphragm thus leading to sound production.
As tiers is no material medium or air toners the rear surface of the diaphragm TV no oimd is created into die canine or enclosure dies completely dominating the possibility of cabinet colorations.
As per the invention, a transducer device, acoustic per, to reproduce sound from deictic sigil, vats out imparting any coloration and to produce sound exactly in accordance to the input signed &node comprising of: -
electro mechanical apparatus - means to convert electrical signal to mechanical vibrations,
diaphragm - means to convert the said mechanical vibrations to sound, voice coil - part of electro mechanical apparatus (magnetic type), enclosure - means to enclose the rear surface of daphragrn and houses the electroHTiechanical apparatus.
such that mien the said enclosure, Is fixed to the rear side of the said diaphragms, is evacuated and near vacuum Is achieved, the said dteiphragn due to differential pressure deforms and settles In an eqiiilfbilum portion, the said electros mechanical apparatus vibrates the diaphragpn according to the electric signal thus prodding sound,
such that, there is no material medium or air toe the rear surface of the said daphragn, and accordingly no sound can be created In or trade through vacuum, so no sound waves are remitted Into the said enclosure thus ellnnAnadng any coloration due to reflected sound waves and enclosure resonance.
Wireman the said enclosure is evacuated to near vacuum or to the desired pressure level and the diaphragm Is designed such that due to the differential pressure acting on it, the electrometric/soft plastic part of It deforms and settles at an equilibrium position where external force due to the air pressure is equal to the intimae forces developed in the said elastomer1c/!soft plastic part of diaphragrn due to deformation i.e. forces due to shear and compressive strain, and
wherein the transducer device has the characteristics of total diminution of cordon due to reflected sound waves and enclosure resonance.-
According to the present invention, a transducer device, acoustic type, the said diaphragm can be of types:-simple cRaphragpn, composite cfiaphragn , piazza electric diaphrsgrn, and combination of any or all of the above
According to the present invention, a transducer deice, acoustic type wherein simple diapers, can be made of an Eastover or from softened plastics soft PVC vat high resilience i.e. vetch very low compression set
between 30 to 80 IRHO and initial modulus between abs Map and 11 Map can be used.
According to the present invention, a transducer device, acoustic type, wherein said Composite diaphragm essentially consists of to parts i.e. central portion and peripheral electrometric/soft plastic rim,
the said central portion is made of hard plastics lies Teflon or of lit metal line Titration, Alunrtlnum and others,
the salad central portion also incorporates in it, the said vodka coil, a part of magnetic type of electro-mechanical apparatus, as claimed in dame 1, it is more or less signalers to a plate or a cone,
the said peripheral electrometric/soft plastic rim can be made of same material as the said simple diaphragm, it is serial to a hollow truncated cone.
According to the invention, a transducer device, wherein Pizza electric diaphragm consists of a thin layer of Pizza electric crystal attuned to a metal plate or dandified batsmen tem metal plates, thus elirriinating said electro-mechanical apparatus as it can itself respond to clerical signals and produce vibrations and thus sound.
According to the invention, a transducer device v erred tie diapered can be a oomisqnation of combination of composite diaphragm ark pies electric diaphragm such that pies-electric diaphragm is minted over the central portion of the composite diaphragm and the chamber behind it is connected to evacuated enclosure chamber by a channel or hide.
According to the invention, a transducer device, wherein the said electro mechanical apparatus can of two types: Magnetic Types, and Pizza electric types.
According to the invention, a transducer device, wherein the said magnetic type means consists of magnetic apparatus and sailed voice cal, shred the said magnetic apparatus creates a uniform magnetic field along which the cal moves according to the current flowing through the said cal, and the said voice ceil bang attached to the said diaphragm, transfers the vibrations created In It to the said daphragrn thus creating sound.
According to the Invention, a transducer device, herd the said apparatus consists of a thin layer of piezoelectric crystal attached to a metal plate or snatched between taw rural plates, when the electric slap Is fed to the crystal It chronics and expands creating vibrations, and said vitiations from the said piezoelectric apparatus, white Is attached to the said diaphragm, are transferred to the said diaphragm thus creating sound.
According to the Invention, a transducer device, v4ierdn the said enclosure encloses the rear surface of the sand cfiaphragrn and houses the sad electromechanical apparatus, the said enclosure has an airtight arrangement and has a valve to vacuous It and to retain the vacuum, the said enclosure Is made from a very hard material, such as hard pasties like Teflon and others or metals like Aluminum and others, so as not to absorb the vibrations from the diaphragm resting on It, the said enclosure has adequate provisions for Inlet of the roes carrying electrical signal to the said electro- mechanical apparatus.
According to the Invention, a transducer dace, the electrical signal Is either fed to the said electromechanical apparatus or directly to the said diaphragm In the case of said pies clearly diaphragm and thereby vibrations are created In the said diaphragpn leading to sound production, the said pie electric cipher enables to produce high frequency sounds where minimal displacement of the said diaphragm Is necessary during operation, jading the effect of high mechanical Impedance tolerable.
DESCWPTION OF DRAWINGS;
Figure 1 : Depicts the side view of the simple diaphragm It roué resembles a dome. It is made entirely from lassoers like Silicone ruttier, EPCM, Neoprene and Others or from softened plastics like Soft PVC.
Figure 2: Depicts the cross section view of simple diaphragrn.
Fiaure3 : Depicts the deformed section view of the simple haphtarah \Mien the chamber towards its rear surface is evacuated the diaphragm deforms due to the differential air pressure acting on It. It then settees in an equilibrium position as shown in the able figure. At that position the external forces due to differential air pressure are compensated by Internal forces due to the denomination 1.e. forces due to shear and compressive strain.
Figure 4: Depicts the cross section view of the composite diafragru It consists of two parts as Illustrated In the ago/e figure. One Is the Peripheral dastomerlc/soft plastic part and the other is the central metal/pleads part. The central metal/plastic part can incorporate In it and the vice cal part of the electro-mechanical asparagus as shown in the figure.
Figure 5 : Depicts the deformed section view of the composite depraving. Wine the chamber behind is evacuated the elastomeiic/soft plastic part of it deforms due to the differential air pressure and settles In an equilibrium position as shod Mi in the above figure. At this position the force due to differential air pressure is compensated by Intermix forces Inside the dastomerlc/soft plastic part due to defoliations i.e. forces due to shear and compressive strain.
Figure 6 : Depicts the cross section view of the composite diapered vetch conical
central metal/plastic part it is miler to the composite diaphragm
illustrated before except that the central metai/plasdc part is conical for better d reactivity of the emitted sound waves.
Tulare 7: Depicts the cross section view of the piezo-elearlc diaphragms. Tie top figure shows a pezD-electrlc diaphragm where the pesos crystal is attached to a metal plate. The below figure shows a pled electric diaphragm veer the fame crystal Is sandwiched between two metal plates we may be the type the above shown diaphragms are capable of responding to electrical signals and produce high frequency sounds without distortion. The deformation in them Wine the rear chamber is evacuated is negligible.
Figure 8 : Depicts the cross section view of the combination of composite diaphragm and pies-electric daphragpi. In the ago/e figure a piece-electric diaphragm Is mounted over the central mental/plastic part of the composite diaphragm. The chamber on the rear side of the piezo-electric diaphragm Is connected to the enclosure chamber by ides In the central part of the composite diaphragm to convey the vacuum. This particular combination enables the transducer to produce both low and hl;^ frequency sounds with out phase distortion.
Figure 9 : Depicts the cross section of the transducer. In this case a composite diaphragm v^th flat central portion rests on the grove for It on the enclosure. The attachment of diaphragm and enclosure is airtight. The enclosure leas a valve (P) to evacuate the dumber and then retain the vacuum, it has sis Inlet for virus carrying electric signal to the electro mechanical apparatus. The enclosure houses the electro-median cal apparatus.
Figure 10 : Depicts the side view of the transducer. In the side view of the transducer the electrometric/soft plastic part of the diaphragm Is visible as a bulge. This is the view after the enclosure Is evacuated and the diaphragm deforms and setties in the desired equilibrium position.
Figure 11 : Depicts the front view of the transducer.
The advantage from this Invention Is that pure quality of sound zero cabinet coloration can achieved at a reasonable cost.
Further the commercially used sweaters that exhibit low cabinet coloration use wave gemmed pipe' or Transmission line pipe* technology Where long pipes of up to three meters length are attached to the rear end of the driver so that sound eventually gets absorbed without getting replied. So they have very large cabinets occupying 160 to 300 liters of space &n6 they are made from costly acoustic materials increasing the cost and size of the equipment.
They are so economical In space that they can have a maximum tallness of Bam to •40rTYn making them a near substitute to flat panel.
1. A transducer device, acoustic type, to reproduce sound from electric signal, with out Imparting any coloration and to produce sound exactly in accordance to the input signal and comprising of: -
electro mechanical apparatus -having a voice cell to convert electrical
signal to mechanical vibrations,
diaphragms - to convert the said mechanical vibrations to sound, and enclosure - to enclose the rear surface of diaphragm and houses the doctor-mechanical appertains,
Valier the said enclosure, \Mice is fixed to the rear side of the said diaphragn, is evacuated and near vacuum is achieved, the said diaphragm due to differential pressure defames and settles In an equilibrium position, the said electro mechanical apparatus vibrates the daphragm accords to the detract signal thus prodding sound,
Vivien there is no material medium or air taverns the rear surface of the said diaphragn, and accordion no sound can be created in or travel throe vacuum, so no sound verves are emitted Into the said enclosure etuis ellnnilnaling any coloration due to reflected sound waves and enclosure resonance.
the said enclosure Is evacuated to near vacuum or to a predetermined pressure level the diaphragn due to the differential pressure acting on it, deforms and settles at an equilibrium position veer external fcM-ce due to the air pressure is equal to the intermix forces developed in the diaphragn due to deformation I.e. forces due to shear and compressive strain, and
the transducer device has the characteristics of total elimination of coloration due to reflected sound waves and enclosure resonance.
resting on It, the said enclosure has adequate precisions for Inlet of the wires carrying electrical signal to the said electro- mechanical apparatus.
11. A transducer device, as denied in dim 1, the electrical signal its either fed
to the said electromechanical apparatus or directly to the said diaphragm in the
case of said pie electric diaphragms and thereby vibrations are created in the
said diaphragn leading to sound production, the said pesos electric diaphragm
enables to produce high frequency sounds jerk rrlnimal disk A cement Of the said
diaphragm is necessary during operation, maiming the effect of high mechanical
12. A trsuisducer device, as dammed in dam 1, Wherein the trvisducer device
has the characteristics of quality of sound vats zero coloration.
13w A transducer device, as maimed in aim 1, as herein before described and
as illustrated with reference to the accompanying drawings.
|Indian Patent Application Number||578/MAS/2000|
|PG Journal Number||36/2010|
|Date of Filing||25-Jul-2000|
|Name of Patentee||PRAVEEN BARATAM|
|Applicant Address||49-12-1, LALITHA NAGAR, VISHAKHAPATNAM-530 016, STATE OF ANDHRA PRADESH, INDIA|
|PCT International Classification Number||H04R17/00|
|PCT International Application Number||N/A|
|PCT International Filing date|