US 3766318 A
A compact, hand held multivibrator activated artificial larynx to provide artificial voices of improved naturalness and intelligibility for patients having laryngectomy operations. Said artificial voice box being provided with push to talk switch means for intermittent operation, requiring only one hand to operate and use and adapted to produce a range of adjustable tones for loud and more natural voice reproduction.
Claims available in
Description (OCR text may contain errors)
United States Patent [191 Webb [ ELECTRONIC VOICE BOX APPARATUS  Inventor: Howard A. Webb, Austin, Tex.
 Assignee: Mary E. Morris, Austin, Tex.;
a part interest [22 Filed: Aiii-ffi ff97 i  Appl. N0.: 135,155
 11.8. C1. 179/1 AL, 3/1.3  Int. Cl. ..A61f1/20, G101 1/10  Field of Search 3/1.3, l, 1.1; 179/1 AL, 121 C, 114 A, 115 A; 272/14; 128/1 R, 1 C
 References Cited UNITED STATES PATENTS 3,066,186 11/1962 Trammell 179/1 AL 3,072,745 1/1963 Barney 3/1.3 X
FOREIGN PATENTS OR APPLICATIONS 619,129 3/1961 Italy 128/1 C Primary Examiner-Richard A. Gaudet Assistant Examiner-Ronald L. Frinks Attorney-Marion E. Shafer [5 7] ABSTRACT A compact, hand held multivibrator activated artificial larynx to provide artificial voices of improved naturalness and intelligibility for patients having laryngectomy operations. Said artificial voice box being provided with push to talk switch means for intermittent operation, requiring only one hand to operate and use and adapted to produce a range of adjustable tones for loud and more natural voice reproduction.
1 Claim, 6 Drawing Figures Patented 0 53-; a ts-Sheet l F/GZ /I LLLU ILLLU "Wu 1 n I HOWARD A. WEBB INVENTOR.
ATTORNEY Patented Get. 16, 1973 2 Sheets-Sheet 2 FIG. 6
HOWARD A. WEBB INVENTOR. BYWM ATTORNEY ELECTRONIC VOICE BOX APPARATUS SUBJECT MATTER OF INVENTION This Invention relates to artificial larynxes and more particularly relates to unitary hand held electronic voice box apparatus.
BACKGROUND OF THE INVENTION In a variety of accidental injury and throat infection cases including malignant laryngeal tumors it often becomes necessary to perform a laryngectomy in which the larynx or voice box is removed. In such circumstances the patient incurs a highly frustrating loss of .speech. Efforts to teach laryngectomy patients to speak by conventional esophageal speech techniques of swollowing air and attempting to belch it back in such a manner as to produce an audible sound that can be modulated into near speech like words is both a slow and difficult substitute for speech and is produced with such apparent labored effort that it is exhausting to both the speaker and those attempting to understand him.
Patients who have difficulty with esophagel speech techniques often despair of ever learning to speak again and suffer psycologically induced depression that adds to the complication of an already difficult situation. In order to provide a convenient and more quickly and more easily mastered means and technique of speaking, a variety of so called vibrator sound sources, artificial voice boxes and electronic tone generators have been provided for injecting a steady tone into the mouth of a laryngectomy patient that can be modulated for speech purposes to a considerable extent by manipulation of the patients tongue and lips. These devices have permitted the patient to regain a measure of ability to speak within a very short time and therefore provide substantial encouragement to the patient during the critical period but such devices have often tended to be somewhat awkward in handling, have usually produced a substantially continuous tone once they were turned on so that uninterupted tone between words interferes with intelligibility of the speech pattern and in addition the usually flat speech pattern resulting from speaking with a single tone source produces a disconcertingly unnatural sound.
OBJECTS OF THE INVENTION It is therefore a primary object of this Invention to provide a highly compact, portable and self contained electronic voice box source of speech modulatable sound that can be conveniently held and manipulated in one hand in such manner as to leave the other hand free for writing, holding a telephone or performing 7 other tasks.
Another object of the Invention is to provide improved artificial voice box apparatus provided with a conveniently positioned push to talk switch means for intermittent operation thereby allowing the patient to conveniently. interrupt the sound source during pauses in the speech pattern and during periods when other people are speaking. A further object of this Invention is to produce an artificial voice source for such laryngectomy patients that can provide substantially increased volume or loudness and that is better suited to produce the frequency and character of sounds that may be transmitted intelligibly over the telephone.
A still further object of the Invention is to provide compact multivibrator electronic means of activating an improved sound transducer capable of producing a complex waveform rich in harmonics to provide a more audible and more natural sound for the person using the device.
These and other objects and advantages of this Invention will become apparent through consideration of the following description and appended claims in conjunction with the attached drawings in which:
DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS FIG. 1 is a perspective view of a person holding the device contemplated by this Invention in proper position for use with his thumb in position to activate the push to talk button on said electronic artificial voice box.
FIG. 2 is a section plan view from one side of the Invention illustrating arrangement of electronic parts inside of the housing package.
FIG. 3 is a front edge plan view of the device illustrated in FIG. 2 showing positioning of the voice transducer device.
FIG. 4 is an exploded perspective view of the details of the voice transducer device.
FIG. 5 is a schematic diagram of the electronic circuit employed to produce the drive signal that actuates the transducer device.
FIG. 6 is a graphical waveform analysis of one of the possible preferred waveforms attainable with the use of the device described herein.
In describing one selected form of preferred embodiment as shown in the Drawings and described in this specification, specific terms and components are used for clarity. However, it is not intended to limit the claimed Invention to the specific form, components or construction shown and it is to be understood that the specific terms used in this illustration of the Invention are intended to include all technical equivalents which operate in a similar manner to accomplish a similar purpose.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENT OF INVENTION The specific embodiment of an improved unitary hand held multivibrator activated artificial voice box sound source selected for purposes for illustration herein consists generally of a compact housing structure, an astable, solid state, free running multivibrator, signal generator with provision for the variable symmetry output signal together with vibrator relay coupling of said variable symmetry output waveform to an appropriate electromechanical acoustic transducer with associated power supply and control devices.
- An object of the improved device contemplated by this Invention being to create a miniature hand held voice box for intermittent use that may be used as simply and as easily as placing a cigarette in the user's mouth as illustrated in FIG. 1 of the Drawings herein, the device has been fabricated to fit into a plastic package or housing 11 approximately a size slightly smaller than the dimensions of a king size cigarrette package. Like a cigarette package said electronic package housing 11 has a width greater than the thickness dimension of the package and has a height or length greater than the width of said package. Miniature electronic transducer unit 12 is mounted on the upper end of housing package 11 on one of the minimum dimension edge surfaces while the push-to-talk off-on switch means 13 is mounted on one of the broader width sides of electronic housing package 11 so that the thumb of the users hand holding the package may be employed to actuate said push-to-talk off-on switch means 13. FIG. 1 illustrates said housing package arranged for a left handed person but it will be readily understood that a reversal of positioning of either the switch or the transducer to an opposite surface will adapt the device to convenient one handed usage by right handed persons. The remaining features of electronics housing package 1 1 are conventional and may be readily deduced or understood by examination of FIGS. 1 through 3 of the Drawings herein. The improved voice box apparatus proposed herein contemplates the production of a loud, clear and readily modulatable tone signal of improved intelligibility by producing a variable symmetry generally rectangular waveform rich in harmonics. This is accomplished by a combination of features and specially selected components including a variable symmetry astable solid state multivib'rator circuit, to be discussed later, employment of an electromagnetically actuated single pole vibrating reed switch 14 employed both as an electromechanical coupling device and as a high contrast driving device for delivering a new high amplitude output signal to a selective electromechanical acoustic transducer unit 12. The internal electromagnetic driver unit 15 including a voice coil 15 and diaphragm 16 of miniature transducer unit 12 are specially selected commercial driver elements capable of handling a high voltage acoustic output. Rear casing unit 17 is of standard commercial manufacture although the upper cover of transducer unit 12 has been specially fabricated with surface mounting ears and an axially positioned external coupling throat projection 18 which serves as a means of mounting flexible injection tube 19 as illustrated in detail in FIG. 4 of the Drawings herein.
The output signal from transducer unit 12 is acoustically coupled into the-oral cavity of the user by means of a flexible plastic injector tube 19 which is friction fitted onto throat structure 18 provided on the external cover of transducer unit 12. The employment of a flexible coupling or injector tube protects the user against accidental injury by sudden forceful collision between injector tube 19 and the lips or teeth of the users mouth and also permits the user to lower said voice box package 11 out of direct view of the users face while using the instrument. It should be readily apparent from examination of FIG. 1 of the Drawings herein that the device as designed and fabricated lends itself to manual intermittent use only at those moments when the user actually wishes to speak and that it can be readily removed or laid aside when the user is not speaking or when the'user is engaged in other activity.
Returning to an analysis of the solid state signal generator selected for this embodiment of the Invention, all of the electronically actuatable parts are wired in parallel with or across built in primary battery energizer 20 which is in turn in series with push-to-talk offon switch 13 which permits the user to employ the device intermittently at will. Transistor 21 and transistor 22 are wired into a substantially conventional free running multivibrator circuit with the pulse output of transistor 21 cross coupled by means of coupling capacitor 23 into the input of transistor 22. Conversely the pulse output signal from transistor 22 is cross coupled by means of coupling capacitor 24 back into the base input of transistor 21 such that each of said transistor pulse circuits consecutively drive first one then the other of said two pulse circuits into cut off so that transistor 21 is conducting when transistor 22 is cut off or alternately transistor 22 is conducting when transistor 21 is cut off in the familiar pattern for free running multivibrator circuits. The output pulse width for one half of the output waveform is determined by the discharge time constant of coupling capacitor 23 through resistor 25 whereas the pulse width of the alternate side of the rectangular output waveforms is determined by the discharged time constant of coupling capacitor 24 through resistor 26.
The output pulse from transistor circuit 22 has been made asymmetrical or longer than the output from transistor circuit 21 by adding to the capacitance of coupling capacitor 24 the additional capacitance of capacitor 27 which for all effective purposes is wired in parallel with coupling capacitor 24 so that the combined capacitance of capacitor 24 plus capacitor 27 together lengthen the time constant for the discharge of capacitor 24 through resistor 26 and this increment of increased pulse-width caused by the parallel connection of capacitor 27 has been made variable by'pulse width control rheostat 28 so that the time constant for dischargingcapacitor 27 through .variable resistor 28 may be adjusted to the convenience and preferences of the user of the device. 7
The output pulse from the collector of transistor 22 is routed through the input solenoid coil 29 of vibrating reed switch 14 so that solenoid coil 29 serves as a load circuit for transistor 22 and also actuates vibrating reed contactor 30 to vibrate in accordance with the frequency and the pulse-width of the signals received from the output of transistor 22. The switched side of vibrator switch 14 is wired in series with a driver battery energizer 31 and the voice coil 15' of electromechanical transducer unit 12 so that the diaphragm of transducer 12 is driven by DC pulses from battery energizer 31 as the DC circuit through vibrating reed switch 14 is opened and closed by the alternating vibrations of vibrating reed contactor 30 in accordance with the frequency and the pulse-width of the signals received from the previously described multivibrator signal generating circuit. It should be noted that vibrating reed switch 14 is employed as a coupling device for transfer of the signal developed by the free running multivibrator signal generator to transducer unit 12 and also serves as a mechanical repeater releasing a larger supply of DC energy from driver batter energizer 31 at a frequency and pulse-width rate controlled by the multivibrator signal applied to input solenoid 29. FIG. 6 of the Drawings herein provides an oscilloscope graphic waveform analysis of the electrical output signal presented to transducer 12. During the longer positive half cycle the pulse-width is affirmatively driven by current flow from driver energizer battery 31 with several overshoots on the first part of the leading half cycle. During the shorter negative half cycle it will be observed that diaphragm 16 of transreed switch 14 is held open by the signal from said free running multivibrating signal generator. Also note that at the beginning of the negative half cycle that there is a radical overshoot which may represent a feedback reaction from the voice coil 15' of transducer 12. In any event the combination of components described produces an anti symmetrical waveform with a steeply rising leading edge and a rapidly falling trailing edge with a rich supply of harmonics at the beginning of each positive pulse. By employing a vibrating reed switch 14 repeater to provide both coupling and additional signal drive, the Inventor has been able to develope a high contrast or high amplitude asymmetrical rectangular waveform with a large and useful harmonic content that makes for a more natural carrier tone signal and by providing for a convenient means of supplying intermittent signal tone when needed by depressing a conveniently situated thumb operated push-to-talk switch in the circuit the proposed structure has made it possible to disable or silence the carrying tone during the intermittent pause between words and sentences and when the user is not speaking.
Returning to the physical arrangement of the components within the electronics housing package ll. The lower parts of the interior of said housing structure 11 is occupied by insertable removable replaceable energizer batteries 20 and 31 as illustrated in FIG. 2 of the Drawings. Most of the electronic components are mounted on a small aluminum chassis 32 or upon an electronic printed circuit board 33 as illustrated in FIG. 2 of the Drawings. Vibrating reed switch 14 is mounted in one corner of aluminum chassis 32. However, note that the specific arrangement of components as illustrated in FIG. 2 and in FIG. 3 of the Drawings is not mandatory or critical and the exact physical placement of pulse-width control rheostat 28 has not been indicated. The exact positioning of most of the physical components including the positioning of said pulsewidth control rheostat is a mechanical matter within the disgression of a manufacturer or fabricator and a volume control could likewise be provided without departing from the spirit or purpose of the Invention.
OPERATION In normal operation the person desiring to use said electronic voice box holds the device in one hand as illustrated in FIG. 1 of the Drawings and raises said voice box until it is directly in front of the lower part of the user's face at which time he inserts sound injector tube 19 into his mouth and simultaneously employs his thumb to depress push-to-talk off-on switch 13 which causes the free running multivibrator signal generator to go into oscillation thereby producing the rectangular wave shape signal previously described. Said asymmetrical output signal is converted from electrical form into an acoustic signal in transducer 12 and is coupled into the mouth of the user by means of flexible injection tube 19. The user then employs his lips and his tongue to modulate said flow of electronically produced sound to form words and communication sounds in much the same way that we use our lips and tongues to formulate words from the tones produced by our vocal chords. In the pauses between sentences or while waiting for other persons to speak the user can disable and silence the device simply by releasing his or her thumb from the press-to-talk off-on switch. The application and mastery of the use of the device is so simple that most users should be able to teach themselves to operate the device by trial and error efforts within less than an hour after acquiring possession of the device.
ADVANTAGES A material advantage of the Invention is that it provides a highly compact, portable and self-contained electronic voice box source of speech modulatable sound that can be conveniently held and manipulated in one hand in such manner as to leave the other hand free for writing, holding a telephone or performing other tasks.
Another advantage of the Invention is that it provides an improved artificial voice box apparatus provided with a conveniently positioned push-to-talk switch means for intermittent operation thereby allowing the patient or user to conveniently interrupt the sound source during pauses in the speech pattern and during periods when other people are speaking so that this particular device does not produce an annoying background tone or noise during periods of nonuse.
Still a further advantage of this Invention is that the combination of selected design and components and the employment of a vibrating reed switch as a portion of the driver-repeater stage of the device produces an artificial voice source for laryngectomy patients that provides a substantially increased volume or loudness that is better suited to produce the frequency andcharacter of sounds that may be transmitted intelligibly over the telephone.
A still further advantage of the Invention is that it provides a compact multivibrator electronic means of activating an improved sound generator capable of producing an asymetrical complex waveform rich in harmonies to provide a more audible, more readily modulatable and more natural sound for persons using the device.
Although this Specification describes but a single embodiment of the Invention with certain applications thereof, it should be understood that structural or material rearrangements or adequate or equivalent parts, substitutions of equivalent functional elements and other modifications in structure can be made and other applications devised without departing from the spirit and scope of my Invention. I therefore desire that the description and drawings herein be regarded only as an illustration of my Invention and that the Invention be regarded as limited only as set forth in the following claims, or as required by the prior art.
Having thus described my invention, I claim: 1. An improved unitary head held multivibrator activated artificial voice box sound source comprising:
A. an electronics package housing approximately the size of a king size cigarette package; B. a transistorized, anti-symmetrical, free running multivibrator signal generating circuit; C. a built in battery power supply to energize said transistorized multivibrator circuit; D. a push to talk, off on switch means 1. wired in series with said battery power supply,
and 2. located on one of the upper side panels of said housing package where it can conveniently be reached for intermittent operation by the thumb of the operators hand holding the device;
7 8 E. a miniature electromagnetic acoustic transducer being wired in series with the load circuit of one unit connected to the output of one half of said f th l i ib t transistors, d
multivibrator circuit with said transducer I. mounted in a surface mount housing on the upper forward edge panel of said electronic housing package, and
2. the switched side of said vibrator switch being wired in series with a battery energizer and in series with the voice coil of said miniature trans- 2. being provided with an axially positioned output ducerf throat Structure; G. a flexible in ector tube connected to the trans- F. an electromagnetically actuated single pole vibratducal throat structure and adapted to transmit the ing reed switch with 10 audio signal into the mouth of the user. 1. the solenoid coil of said vibrating reed switch