WO1997004617A1

WO1997004617A1 - Personal listening device

Info

Publication number: WO1997004617A1
Application number: PCT/IB1995/000599
Authority: WO
Inventors: Gunnar FESSÉ
Original assignee: Comento Ab
Priority date: 1995-07-18
Filing date: 1995-07-18
Publication date: 1997-02-06
Also published as: AU2935595A

Abstract

A personal listening device includes an amplifier with an automatic gain control circuit for automatically limiting at the amplified output the amplitude of electrical signals supplied to the signal input. A directional microphone is connected to the signal input of the amplifier, the directional microphone produces electrical signals representative of sounds prevalent at a position at which the microphone is directed. The amplifier and directional microphone are mounted in an ergonomically designed housing for easy direction of the microphone. Earphones or a hearing aid are connected to receive the amplified electrical signals from the amplifier and convert the electrical signals to sound.

Description

PERSONAL LISTENING DEVICE

Technical Field

This invention relates to personal listening devices. More particularly, the present invention relates to a personal listening device for hearing impaired people.

In a further and more specific aspect, the instant invention concerns a personal listening device for hearing impaired people with light to moderate hearing impairments.

Background Art

Many older people are healthy and live active lives well into their golden years. But the risk of becoming ill or disabled increases with the years. This applies particularly to hearing. The percentage of people with impaired hearing increases dramatically with age. Also, in most instances the amount of hearing impairment increases with age.

Generally, as a person's hearing gradually fails, they must gradually increase the sound output, e.g. turn up the sound on radios, televisions, etc. Ultimately, they must purchase some sort of hearing aid. Most listening devices are limited to an in-the-ear device that simply amplifies all sound approximately equally

(sometimes amplifying certain tones a greater amount) .

A major problem with prior art listening devices which amplify all ambient sounds is that a hearing impaired person has great problems hearing what any one person says when other people are talking at the same time or in noisy places. The microphone in a conventional listening device is omnidirectional (picks up the sound approximately equally from all directions) .

Further, the amplification in conventional listening devices is fixed and, after being set with a manual control, remains constant regardless of the sound or noise level. Thus, sudden loud noises, etc. are over amplified and can even be painful to the wearer. Also, because of the constant amplification, a conventional listening device is very sensitive to acoustic feedback when the distance between the microphone and headphones is too close and/or the volume control is set too high.

It would be highly advantageous, therefore, to remedy the foregoing and other deficiencies inherent in the prior art.

Accordingly, it is an object of the present invention to provide an improved personal listening device.

Another object of the present invention is to provide an improved personal listening device that operates substantially automatically.

And another object of the present invention is to provide an improved personal listening device that can be worn or positioned in a convenient location.

Yet another object of the present invention is to provide an improved personal security system which can be used even in very noisy environments.

Disclosure of the Invention

Briefly, to achieve the desired objects of the instant invention, in accordance with a preferred embodiment thereof, a personal listening device includes an amplifier with an electrical signal input and an amplified electrical signal output, and an automatic gain control circuit for automatically limiting at the amplified electrical signal output the amplitude of electrical signals supplied to the electrical signal input. A directional microphone having an electrical signal output is connected to the electrical signal input of the amplifier, the directional microphone produces electrical signals at the electrical signal output representative of sounds prevalent at a position at which the microphone is directed.

The amplifier and directional microphone are mounted in a common portable housing ergonomically fashions as an elongated tubular structure with the directional microphone mounted adjacent one end and directed at an angle to the elongated tubular structure for ease in automatically or manually directing the microphone at a preferred position. Also, The common portable housing is constructed to be carried by a neck strap, which generally points the directional microphone in a direction in which a wearer is facing when the common portable housing is carried by the neck strap.

The personal listening device includes in addition a transponder connected to receive electrical signals from the amplified electrical signal output of the amplifier and convert the electrical signals to sound.

Brief Description of the Drawings

The foregoing and further and more specific objects and advantages of the instant invention will become readily apparent to those skilled in the art from the following detailed description of preferred embodiments thereof taken in conjunction with the drawings in which: FIG. 1 is a top perspective view of a personal listening device, constructed in accordance with the present invention;

FIG. 2 is a bottom perspective view of the personal listening device of FIG. 1; FIG. 3 is a schematic view of the personal listening device of FIG. 1; and

FIG. 4 is a view of an accessory for the personal listening device of FIG. 1.

Best Mode for Carrying Out the Invention

Turning now to the drawings in which like reference characters indicate corresponding elements, attention is first directed to FIG. 1 which illustrates a personal listening device 10 including a common portable housing 11. Common portable housing 11 is formed as an elongated tubular structure with a directional microphone 15 mounted adjacent one end and directed at an angle to the elongated tubular structure. FIG. 1 generally illustrates the upper portion of housing 11 and includes a dual function on/off switch and volume control 16. An indicator light 17 is positioned adjacent on/off switch 16 so as to be easily viewable when operating on/off switch 16. Referring to FIG. 2, a bottom view of housing 11 is illustrated, showing a battery compartment 18 which contains batteries for powering personal listening device 10. Also, a pre-selector switch 19 is illustrated which is utilized to provide specific tone control (e.g. selecting a specific frequency response, such as reduction of high or base tones) . A pair of mounts 20 are cast in housing 11 for connecting a neck strap 25 to housing 11 for affixing personal listening device 10 about the neck of a user. It should be specifically noted that housing 11 is formed as an elongated tubular structure with directional microphone 15 mounted adjacent one end and directed at an angle to the elongated tubular structure so as to generally point directional microphone 15 in a direction in which the wearer is facing when common portable housing 11 is carried by neck strap 25. Further, common portable housing 11 is ergonomically designed to fit the hand or to be conveniently carried by neck strap 25 about the neck of a user. A headphone jack 26 is provided on the side of housing 11 for the connection of a headphone (not shown) .

Referring specifically to FIG. 3, a schematic diagram of personal listening device 10 is illustrated. Directional microphone 15 is connected directly to a single transistor amplifier 30. An input jack 32 is provided in circuit with directional microphone 15 so that other inputs can be connected to amplifier 30 and directional microphone 15 will be automatically disconnected from the circuit. In the normal mode of operation, electrical signals input to amplifier 30 from directional microphone 15 are amplified and supplied through an automatic gain control circuit 35, illustrated herein as an integrated circuit, to a two input differential amplifier 40. In this embodiment the integrated circuit is a compander I.C. used as a level limiter. In case of high amplitude incoming signals, the I.C. regulates the amplitude successively and very smoothly down to predetermined levels. Differential amplifier 40 provides a dual output to an output jack 45 designed to receive, a transponder which may be for example, a pair of earphones 50 connected thereto. Amplifier 30 and differential amplifier 45 receive power from a power supply 55, which is in turn connected to one or more batteries 56 positioned in battery compartment 18.

In the specific embodiment illustrated in FIG. 3, the values of the various components of amplifier 30, automatic gain control circuit 35 and differential amplifier 40 are generally as follows:

Cl, C2, C4 220nF

C3 lOnF

C5, lOOnF C6 , C7 , C9 , CI O , C13 , C15 luF Cl l , C12 , C14 47uF

Rl, R4 4.7kOhms

R2, R3 188k

R5 1.8k

R6 330

R7 33k

R8, R9 18k

RIO 15k

Rll 108k

R12, . R13 27

R14 100

ICI TDA7050T

IC2 NE575

Tl BC847

Ll LED

Ml DIRECTIONAL MICROPHONE

Sl, VR1 SWITCH/VOLUME CONTROL

Ji, J2 3.5mm Jack

S2 DIL SWITCH

Batteries are 2 1.5 volt penlight batteries

In the operation of personal listening device 10, housing 11 is ergonomically designed to fit conveniently in the hand or to hang about the neck of an operator by neck strap 25. In either application, directional microphone 15 is conveniently positioned in housing 11 to be substantially automatically directed toward a position in which the operator is looking, e.g. someone with whom the operator is conversing. Therefore, directional microphone 15 picks-up the sounds or voice from the person with whom the operator is conversing and all or most of the other noise or conversations in the area are eliminated. Additionally, automatic gain control circuit 35 automatically maintains the amplitude of the output signals from amplifier 40 at a preset amplitude. Any sudden loud noises that might occur are automatically reduced to the preset level by automatic gain control circuit 35 so that the operator is protected from sudden loud noises, back ground noise, other conversations, etc. Further, the risk of acoustic feedback from some source of sound is substantially removed. Referring to FIG. 4, an accessory transponder for coupling the electrical signals from amplifier 40 to a hearing aid is illustrated. The accessory includes an induction loop 55 connected to be plugged into output jack 45 in place of earphones 50. When the operator desires to connect listening device 10 to a conventional hearing aid, rather than using earphones 50, induction loop 55 is simply plugged into output jack 45 and loop 55 is placed around the neck. The conventional hearing aid can then be set to T for magnetic coil operation and sounds (electrical signals representative of the sounds) are transmitted directly to the hearing aid from personal listening device 10.

In some special applications, other inputs, such as a tie clip microphone (not shown) may be utilized in place of directional microphone 15. Such, special equipment is attached to personal listening device 10 through input jack 32.

Accordingly, an improved personal listening device is disclosed which operates substantially automatically and which can be worn or positioned in a convenient location for individual conversations and the like. Further, the improved personal security system can be used in virtually any noise environment and picks-up speech in close communication very clearly. The personal listening device substantially reduces background noise and automatically regulates the amplification to a pre-set volume. Also, the risk of acoustical feedback is substantially eliminated, as well as the risk of sudden loud noises being unduly amplified. In addition, the structure is ergonomically designed to conveniently fit the hand, hang around the neck, or to be set on a desk or the like for easily and conveniently picking-up conversations between individuals. Accordingly, an improved personal listening device is disclosed which is substantially automatic and can be conveniently, if not automatically, positioned by the wearer to pick-up personal or individual conversations. Further, the improved personal listening device is light and wearable as an attractive piece of jewelry (if desired) so that it can be conveniently included in the wearer's outfit under virtually any circumstances.

Several advantages of the disclosed personal listening device are the simplicity and ease of use and the great versatility. Also, because of the substantially automatic features of the volume and microphone direction, the personal listening device is very easy to use.

Various modifications and changes to the embodiments herein chosen for purposes of illustration will readily occur to those skilled in the art. For example, housing 11 can be formed and assembled in a variety of ways while still performing the stated functions. Further, a variety of different circuits may be utilized to form amplifiers 30 and 40 and automatic gain circuit 35 and a variety of apparatus may be utilized to attractively position the personal listening device conveniently on the body. The foregoing is given by way of example only. Other modifications and variations may be made by those skilled in the art without departing from the scope of the invention as defined by the following claims.

Having fully described and disclosed the present invention and preferred embodiments thereof in such clear and concise terms as to enable those skilled in the art to understand and practice same, the invention claimed is:

Claims

1. A personal listening device comprising: an amplifier with an electrical signal input and an amplified electrical signal output, and an automatic gain control circuit for automatically limiting at the amplified electrical signal output the amplitude of electrical signals supplied to the electrical signal input; and a directional microphone having an electrical signal output connected to the electrical signal input of the amplifier, the directional microphone producing electrical signals at the electrical signal output representative of sounds prevalent at a position at which the microphone is directed.

2. A personal listening device as claimed in claim 1 wherein the amplifier and directional microphone are mounted in a common portable housing.

3. A personal listening device as claimed in claim 2 wherein the common portable housing is an elongated tubular structure with the directional microphone mounted adjacent one end and directed at an angle to the elongated tubular structure.

4. A personal listening device as claimed in claim 1 wherein the common portable housing is constructed to be carried by a neck strap.

5. A personal listening device as claimed in claim 4 wherein the common portable housing constructed to be carried by a neck strap is further constructed to generally point the directional microphone in a direction in which a wearer is facing when the common portable housing is carried by the neck strap.

6. A personal listening device as claimed in claim 4 including in addition a transponder connected to receive electrical signals from the amplified electrical signal output of the amplifier and convert the electrical signals to sound.

7. A personal listening device as claimed in claim 6 wherein the transponder includes earphones.

8. A personal listening device as claimed in claim 6 wherein the transponder includes a hearing aid and means for coupling the electrical signals thereto.

9. A personal listening device as claimed in claim 8 wherein the means for coupling the electrical signals to a hearing aid includes an induction loop.

10. A personal listening device comprising: an amplifier with an electrical signal input and an amplified electrical signal output, and an automatic gain control circuit for automatically limiting at the amplified electrical signal output the amplitude of electrical signals supplied to the electrical signal input; a directional microphone having an electrical signal output connected to the electrical signal input of the amplifier, the directional microphone producing electrical signals at the electrical signal output representative of sounds prevalent at a position at which the microphone is directed; and a transponder connected to receive electrical signals from the amplified electrical signal output of the amplifier and convert the electrical signals to sound.

11. A personal listening device as claimed in claim 10 wherein the transponder includes earphones.

12. A personal listening device as claimed in claim 10 wherein the transponder includes a hearing aid and means for coupling the electrical signals thereto.

13. A personal listening device as claimed in claim 12 wherein the means for coupling the electrical signals to a hearing aid includes an induction loop.

14. A personal listening device as claimed in claim 1 wherein the amplifier and directional microphone are mounted in a common portable housing.

15. A personal listening device as claimed in claim 14 wherein the common portable housing is an elongated tubular structure with the directional microphone mounted adjacent one end and directed at an angle to the elongated tubular structure.