Signalling device for hard of hearing persons

There is disclosed a signalling device for making hard of hearing persons aware of an impending happening in his or her proximity. The device comprises a sound transducer such as a microphone for converting sounds to electrical signals, an amplifier for amplifying the electrical signals and a selective filter connected to the amplifier for selecting amplified signals above a selected amplitude level and within a selected frequency range as may be produced by automobile horns, fire, police and emergency sirens, burglar and smoke alarms, door bells, barking dogs, and the like to produce a continuous, periodically pulsating control signal. These control signals are supplied to an indicator means such as a flashing light-emitting diode connected to a person's spectacles or a tactile alarm secured to the wrist of the person to provide a vibrating or pulsating signal to a sensitive area of the body such as the mastoid bone or the wrist or, alternatively, the device may be connected to a male-female electrical connector with a built-in electronic switch activated by the unit so that a lamp or light bulb plugged therein is turned on and off periodically to awaken the hard of hearing when a smoke alarm or whatever signal is detected.

BACKGROUND AND BRIEF DESCRIPTION OF THE INVENTION 
There have been many instances where persons who are hard of hearing are 
startled or otherwise taken unawares of a possibly dangerous or hazardous 
impending happening in their proximity which, if an alarm be given to the 
hard of hearing, could prevent injury and/or other disastrous 
consequences. Very frequently, such happenings or events are preceded by a 
loud sound, such as an automobile horn, fire, police and emergency sirens, 
burglar alarms, smoke alarms, door bells, barking dogs. The object of the 
present invention is to provide a simplified low cost device which is 
adaptable to provide an early warning to persons hard of hearing and make 
them aware of impending, possibly disastrous happenings in their 
proximity. The device of the present invention comprises a battery powered 
unit capable of receiving signals of frequencies usually associated with 
such sounds which would be cause for alarm for the user. The signalling 
device alerts the user to the need to be aware of an impending happening 
in his proximity and it can be adapted for driving many kinds of 
signalling or inductor devices. In the first case, a small lamp or 
light-emitting diode can be attached to the spectacle frames or temple 
piece for the user who wears "glasses". A microphone or other sound 
transducer is used for detecting the sound made by the impending 
happening, to produce an electrical signal which is amplified, filtered 
and the signal then used to pulsatingly actuate a lamp such as a 
light-emitting diode or to activate a tactile signalling system such as a 
small vibrator worn on the ear adjacent the mastoid bone of the user or on 
his wrist. The same unit can also advantageously be used to act as a night 
alarm for sensing a smoke detector and/or burglar alarm and used to flash 
a table lamp, for example, on and off to arouse the sleeping hard of 
hearing person. 
The above and other objects, advantages, and features of the invention will 
become more apparent when considered with the following specification and 
accompanying drawings wherein:

DETAILED DESCRIPTION 
Referring now to the drawings, FIG. 1 shows a housing 10 containing the 
basic electrical components of the invention, and having an on/off switch 
11 for connecting the electrical circuitry to a battery contained in the 
housing, a low battery voltage signalling lamp 12, which comes on to 
indicate to the user that the battery needs charging, a battery recharge 
jack 13 to which the unit is connected for recharging the internal 
batteries and, at the same time, driving this unit for the night time 
alarm, if desired, a microphone or transducer jack 14 for connecting a 
microphone or transducer input to the electrical circuit contained in the 
housing 10, and a signal output jack 16 for delivering an output signal 
from the driver circuitry to any one or more of a selected number of 
output units shown generally in FIGS. 3-5. 
Referring now to FIG. 1, a microphone 20 which is preferably a wide band 
unidirectional microphone is provided for transducing sound waves to 
electrical signals and providing an output signal voltage to an amplifier 
21. The output voltage from amplifier 21 may be applied to a plurality of 
filter elements 22-A, 22-D, 22-F, each of which can be tuned to select 
frequencies usually associated with sounds that can be a cause for alarm 
to the user, such as, for example, automobile horns (frequency range 500 
to 8000 cycles per second), fire, police and emergency sirens (frequence 
range 500 to 4000 cycles per second), burglar and smoke alarms (frequency 
range 500 to 4000 cycles per second, door bells (frequency range 500 to 
4000 cycles per second), and barking dogs (frequency rang 500 to 2000 
cycles per second). Each of the filters 22 can, if desired, be selectively 
adjusted for selecting different frequencies that the user may wish to be 
particularly informed of in advance. In addition, the level or amplitude 
of the signal from the filter that the user of which is to be warned of or 
sensitized to can be selected by means of a level selector, thus, as shown 
in FIG. 2, the output of the filter 22-A is applied to level detector 23 
which can be adjusted to select a certain level of loudness before a 
signal is transmitted to the user warning device. 
Filters 22-D and 22-F are adjustable filters which may be adjusted to 
select any desired frequency range; there may be several more filters if 
desired, and each selected or tuned to a selected frequency. The output of 
the frequency sensitive or selective circuits 22 is applied via an OR gate 
26 to drive activator circuit 27. Activator circuit 27 includes an 
electronic switch 24, and rate generator 25 such as a multivibrator which 
is activated on by electronic switch 24 (which may be a flip flop). The 
multivibrator output can be adjusted to adjust the frequency, and it is 
amplified by driver circuit 30 so that once a signal of the given 
amplitude and/or frequency is received from OR gate 26, activator circuit 
27 will provide a continuous output signal to the signal jack 29. In this 
way, a single blowing of a horn, a single loud barking of an adjacent dog, 
or a single blowing of a siren or the like will activate the alarm to 
provide a series of continuous pulses, at the rate of the multivibrator, 
to drive the alarm device that the user may be using at that time. For 
example, if the warning or signalling device is a light-emitting diode, it 
will be plugged into the jack 16 by a cable 16C and the light-emitting 
diode will be pulses on and off at the rate set by the multivibrator. Of 
course, the multivibrator can easily be adjusted to provide any rate that 
is desired by the user. In like manner, the signal from the jack 29 can be 
used to drive the wrist unit shown in FIG. 4 which is simply a small 
vibrator coil 35 or a small microphone secured to the wrist of the user by 
Velcro straps 36 so as to warn the user through pressure on his or her 
wrist and/or mastoid (if the unit is secured adjacent the mastoid of the 
user as indicated by dotted tactile element 39 in FIG. 3). Alternatively, 
for night time alarm use, the night time alarm element shown in FIGS. 5A 
and 5B can be used. 
Referring to FIG. 3, in this case, a small light such as a light-emitting 
diode 34 is attached by a spring clip 40 to the spectacle frames or temple 
piece 41 of the user who wears glasses G. When the unit is activated 
through a sound in the sensitivity range selected, the light-emitting 
diode 34 is caused to flash at the rate set by multivibrator 25. A small 
spring clip 40 is used to secure light-emitting diode 34 onto the temple 
piece 41 of the spectacle frames. The user's peripheral vision sees the 
light and he or she is thus alerted to an impending happening and its 
proximity. Alternatively, or in addition to the light-emitting diode, a 
vibrating or pulsing coil 39 is placed in contact with the sensitive area 
of the body, such as the mastoid bone, by securing same to the temple of 
the spectacle frame or by a wrist attachment such as shown in FIG. 4 to 
the wrist bone or the like. When the coil 39 of this unit is activated by 
the signal from the multivibrator 25, a pulsing sensation is registered at 
the contact area, thereby allerting the user to an impending happening in 
his proximity. 
Finally, at night time, hard of hearing persons who cannot hear alarms such 
as burglar and/or smoke alarm systems, can use the present invention as a 
night alarm. In this case, the signal jack 16 has connected thereto a 
small coil 50 which is used to activate a magnetic reed switch 51 
connected in one line of an alternating current circuit contained within 
the housing 52 (FIG. 5A). In this case, the alternating current circuit 52 
has a male plug 53 formed in the rear surface thereof and a pair of wires 
54, 55 leading to a female outlet 56. Reed switch 51 is connected in 
series in line 55 so that the pulsating signal from the multivibrator is 
used to supply a signal to coil 50 to thereby pulsate reed switch 51 and 
thereby pulsate the night lamp 60 that is positioned beside the table (not 
shown) of the user. 
In the preferred embodiment, the housing 10 is removable for battery 
replacement and servicing and is self-contained and about the size of a 
king-sized pack of cigarettes. The unit is powered by a rechargeable 
battery 15 which is connected through the on/off switch 11 to the positive 
terminal to supply power to the circuit shown in FIG. 2. The recharger to 
which the plug in jack 13 is connected is not shown. The circuitry is 
carried on a printed circuit board and, if desired, the filters may be 
electronic filters and formed in printed circuit form. However, because of 
the size of the components needed for filtering some of the lower 
frequencies, the filters may be formed as discrete elements or in 
association with the integrated circuit elements constituted by the 
amplifier, level detector and multivibrators, as well as the OR gates and 
driving circuitry per se. 
The unit is placed in the user's shirt or jacket pocket, or may even be 
attached to his clothing. The microphone 20 is attached to the wearer's 
outer garment for maximum sensitivity. The signalling device, in the case 
of a flashing lamp, is the subminiature light-emitting diode (LED) clipped 
to the temple piece of the frame of the wearer's glasses and the 
connecting wire is placed unobtrusively behind the temple piece, behind 
the ear and down the neck to the unit jack 16. When, as described above, 
the signalling device is used to sensitize the wristbone, a tactile 
activator can be used and contained in a wrist strap which would be 
secured around the wearer's wrist as shown in FIG. 4, the connecting wire 
(not shown) going up the arm to the signal jack 16. In the night alarm use 
described herein, it is plugged into the signal jack in lieu of the 
light-emitting diode and/or wrist unit and operates as described earlier 
to provide a repeating on/off or flashing sequence of light which would 
arouse the sleeping person. This could be operating while the battery unit 
is being charged. The drain on the battery while in the "on" condition is 
considerably less than the rate of charging. Consequently, by morning the 
battery would be sufficiently charged to provide proper service during the 
following day. 
While I have shown, described and illustrated preferred embodiments of the 
invention, it will be appreciated that other adaptations, modifications 
and departures can be made without departing from the spirit and scope of 
the invention as defined in the appended claims.