Apparatus for monitoring persons or the like

The present invention discloses an apparatus for monitoring persons, pets, things and the like including a monitored unit and a monitoring unit each having a transmitter and receiver. The monitored unit is adapted to transmit a periodic signal while the activities of the monitored object coincide with various threshold conditions. The monitored unit includes a plurality of indicators either visual or audio which inform the operator that the monitored unit has exceeded various threshold conditions. The monitoring unit includes a reset transmitter for actuating the monitored unit so that it produces either a continuous signal or a periodic signal. The monitoring unit further includes a homing mechanism automatically actuated upon receipt of either a continuous signal or an alarm signal by its receiver. The monitored unit includes a plurality of sensing switches for informing the operator of the monitoring unit that either the monitored object has energized a manual actuation alarm, someone has tired to remove the monitored unit from the monitored object or the monitored unit has been immersed in water.

FIELD OF THE INVENTION 
This invention relates to an apparatus for monitoring persons, pets, things 
or the like. Specifically, an apparatus capable of informing an operator 
that the activities of the object being monitored have exceeded various 
threshold conditions. 
BACKGROUND OF THE INVENTION 
Numerous devices have been developed to monitor the activities of 
individuals in lieu of the growing concern of children being abducted from 
their parents. The need for monitoring devices, in this particular 
application, has arisen due to the fact that a parent cannot watch his 
child every minute of every day and still go about doing their daily 
tasks. Additionally, monitoring apparatuses have been employed to monitor 
the whereabouts of valuable cargo. Further, these devices have been 
implemented in mental and correctional institutions where the need for 
monitoring inmates is great due to the disproportional ratio of inmates to 
institutional staff members. The following U.S. Pat. Nos. disclose various 
devices for monitoring persons and the like: 3,336,530 Sloan et al; 
3,810,146 Lieb; 4,121,160 Cataldo; 4,136,338 Antenore; 4,157,540 Oros; 
4,300,129 Cataldo; 4,336,531 Kincaid; 4,399,432 Lunn; 4,593,273 Narcisse; 
4,598,272 Cox. The monitoring apparatuses disclosed in the aforementioned 
patents fall into two general categories. The first category being devices 
that only transmit a signal between the monitoring and monitored units 
when an individual activates the device. These types of monitoring 
apparatuses are very limited in their applications. The second major 
category of monitoring apparatuses are those which provide a continuous 
signal between the monitored and monitoring units. These types of 
monitoring devices have been designed to only inform an operator that an 
alarm condition is present and are unable to inform the operator of the 
specific activities of the object which resulted in the alarm condition. 
By providing only a single alarm to inform the operator that a threshold 
condition has been exceeded, these monitoring devices do not in any way 
limit the possibilities which may have given rise to the alarm conditions. 
Therefore, the parent or operator must consider all possibilities as 
opposed to focusing on only a few specific possibilities. This deficiency 
in the known monitoring apparatuses significantly reduce the likelihood 
that the parent/operator will be able to locate the monitored person or 
thing before it is to late. Further, the continuous signal type monitoring 
apparatuses significantly drain the power supply of the unit sending the 
signal. Thus, the batteries or the like are required to be replaced 
frequently. Additionally, the aforementioned monitoring apparatuses are 
unable to readily locate the monitored person or thing once an alarm 
condition has been triggered. Therefore, eventhough the operator is 
informed that an alarm condition is present, he is given no clue as to the 
direction to proceed in order to find the monitored object. 
Prior to the present invention, monitoring apparatuses have not been able 
to monitor the specific activities of an object without significantly 
draining the power supply of the apparatus. Additionally, the prior art 
has been unable to inform the operator as to the specific activity of the 
monitored person which led to the alert condition or conditions. Finally, 
the aforementioned apparatuses have been unable to provide an efficient 
method for locating the monitored individual or the like once an alarm 
condition has surfaced. 
OBJECTS AND SUMMARY OF THE INVENTION 
Accordingly, it is an object of this invention to provide an improved 
apparatus for monitoring persons, pets, things or the like. 
Another object of the invention is to provide a monitoring apparatus of the 
continuous type which significantly reduces the drain on the power supply. 
A further object of the invention is to provide an apparatus for monitoring 
persons, pets, things or the like that will enable the operator to readily 
locate the monitored object once an alarm condition has been triggered. 
Yet another object of the invention is to provide a monitoring apparatus 
capable of monitoring a plurality of activities of the monitored person 
including the relative distance of the monitored person from the 
monitoring unit, whether the monitored unit is still transmitting a 
signal, whether the monitored unit has been removed from the object being 
monitored, whether the object being monitored has been submersed into 
water, and whether the monitored person has manually activated an alarm. 
Another object of the invention is to provide a miniaturized monitored unit 
in order that the monitored unit can be readily concealed on the monitored 
object. 
Another object of the invention is to provide a monitoring apparatus with a 
directional locator or homing device that is automatically activted upon 
receipt of an alarm signal or a continuous signal. 
A further object of the invention is to provide a monitoring apparatus that 
will transmit an alarm signal under various conditions and will maintain 
the alarm signal even though the condition is no longer present until 
deliberately reset by the operator of the monitoring unit. 
Yet another object of the invention is to provide a monitoring apparatus 
for transmitting a periodic signal while threshold conditions are present 
for prolonging the life of the power supply. 
In summary, the present invention discloses a novel apparatus for 
monitoring persons, pets, things and the like that significantly reduces 
the drain on the power supply of the monitoring apparatus, informs the 
operator of the specific activity leading to the alarm condition, and 
provides an efficient and effective method for locating the monitored 
object once the alarm condition has been triggered.

DETAILED DESCRIPTION OF THE INVENTION 
FIGS. 1 through 4 
The monitoring apparatus A formed in accordance with the present invention 
includes a monitored unit B and a monitoring unit C. The monitored unit B 
is placed on the object to be monitored and the monitoring unit C is to be 
worn by the operator/individual monitoring the activities of the monitored 
object. 
The monitored unit B includes a digital logic board 2, a transmitter 4, a 
receiver 6, and three sensing switches 8, 10, and 12. The transmitter 4, 
receiver 6, and switches 8, 10, and 12 are electrically connected to 
digital logic board 2 by lines 14, 16, 18 and 20 respectively. Antennas 22 
and 24 are operably associated with transmitter 4 and receiver 6 
respectively. 
Referring to FIG. 3, the specifics of the digital logic board 2 will be 
hereinafter described. The digital logic board 2 consists of a cycle timer 
26 and a bistable multivibrator 28. The output of the cycle timer 26 is 
operably connected to a first input of OR logic gate 30. The output of 
bistable multivibrator 28 is operably connected to the second input of OR 
gate 30. The output of OR gate 30 is directed to a first input of OR gate 
32. The output of OR gate 32 is connected to transmitter 4. The cycle 
timer 26 generates a periodic signal. A preferable cycle time for the 
cycle timer 26 which drives the carrier signal is one second of signal 
broadcast and fifteen seconds of quiescent or no signal broadcast. 
The bistable multivibrator 28 generates a low and high output depending 
upon the activation of the reset signal by the operator of the monitoring 
unit. During normal operation, i.e., no alarm/alert condition is present, 
the bistable multivibrator 28 generates a low output. In this state, the 
output of the OR gate 30 will track the periodic output of the cycle timer 
26. Therefore, the OR gate will have an output signal transmitted to OR 
gate 32 one second out of every sixteen seconds. It will be obvious to one 
of ordinary skill in the art to vary the cycle time of the unmodulated 
carrier signal produced by the cycle timer 26 to meet the specific needs 
of the user. The monitoring unit C is adapted to reset the bistable 
multivibrator such that it produces a continuous high output. The 
specifics of the activating mechanism of the monitoring unit C will be 
discussed more fully below. While the bistable multivibrator is producing 
a continuous high output, the output of OR gate 30 will be continuous 
resulting in OR gate 32 producing a continuous output. Thus, transmitter 4 
will transmit a continuous unmodulated carrier signal to the monitoring 
unit C. 
The input of bistable multivibrator 28 is operably connected to the 
receiver 6. Also, the input of NOT gate 34 is operably connected to 
receiver 6 and is in parallel with bistable multivibrator 28. The output 
of NOT gate 34 is directed to a first input of AND gate 36. The output of 
AND gate 36 is electrically connected to a first input of OR gate 38. The 
output of OR gate 38 is connected to the second input of AND gate 36, the 
second input of OR gate 32, and the transmitter 4. A high output from OR 
gate 38 activates the modulation circuitry of the transmitter 4 for an 
alarm signal. The output of NOT gate 40 is connected to the second input 
of OR gate 38. Sensing switches 8, 10, and 12 connected in series are 
electrically connected to the input of NOT gate 40. Sensing switches 8, 10 
and 12 are connected in series. The cycle timer 26, bistable multivibrator 
28, and switches 8, 10, and 12 are connected to a power source, not shown. 
Referring to FIG. 2, the specifics of the monitoring unit C will be 
hereinafter described. The monitoring unit C includes a digital logic 
board 42 including visual indicators 44, 46, 48, and 50. It will be 
readily appreciated that monitored unit B could be provided with 
equivalent indicating mechanisms. A receiver 52 and a transmitter 54 are 
electrically connected to digital logic board 42 via lines 53 and 55 
respectively. Receiver 52 includes a unidirectional antenna 56 and a 
directional antenna 58. Unidirectional antenna 56 is adaptable to be 
operably connected to transmitter 54. A directional meter 60 is connected 
to digital logic board 42 via line 62. Buzzer or audio alarm 64 is 
connected to digital logic board 42. Buzzer 64 includes deactivation 
switches 66 and 68. 
Referring to FIG. 4, the specifics of the digital logic board 42 will be 
hereinafter described. Amplifier 72 is operably connected to receiver 52. 
The receiver 52 directs the unmodulated carrier signals, periodic and 
continuous, through amplifier 72. The output of amplifier 72 is connected 
to the input of timer 74 and a first input of AND gate 76. The output from 
timer 74 is connected to indicator 44 and a first input of OR gate 80. 
Indicator 44 informs the operator/attendant that the monitored unit is no 
longer transmitting a signal. The output of OR gate 80 is directed through 
amplifier 82. 
Comparator 84 is operably connected to receiver 52 and compares the 
automatic gain control signal with a preset mechanism 85. The value of the 
preset mechanism 85 can be adjusted through a variable resistor. The 
output of comparator 84 is connected to the second input of AND gate 76. 
The output of AND gate 76 is connected to indicator 46. Indicator 46 
informs the attendant/operator that monitored unit B has exceeded a 
predetermined distance range relative to the monitoring unit C. 
The output of amplifier 72 is further directed to the input of NOT gate 88. 
The output of NOT gate 88 in turn is connected to the input of timer 90. 
The output of timer 90 is directed to the first input of OR gate 92. The 
output of OR gate 92 is in turn connected to indicator 48 and amplifier 
96. Indicator 48 informs the operator/attendant that the monitoring unit C 
is in the search mode. The output of amplifier 96 is connected to search 
relay 98. Inverting amplifier 100 is operably associated with receiver 52 
in order to amplify the automatic gain control signal. The output of 
inverting amplifier 100 is directed to directional meter 60. 
Amplifier 106 is operably associated with receiver 52. Receiver 52 directs 
the modulated alarm signal transmitted by monitored unit B to amplifier 
106. Amplifier 106 amplifies the modulated signal and directs it to 
indicator 50. The outputs of amplifiers 82, 106 and 108 are linked to 
audio alarm 64. Switches 66 and 68 enable the operator to deactivate audio 
alarm 64. 
OPERATION 
The operation of the monitoring apparatus A of the present invention will 
be hereinafter discussed. The monitoring apparatus A operates under three 
basic modes including a normal operation mode, an alarm/alert condition 
mode, and a search mode. 
During normal operation of the monitoring apparatus A, the cycle timer 26 
of the monitored unit B produces a periodic carrier signal and the 
bistable multivibrator 28 produces a low output. Additionally, in the 
normal operation mode switches 8, 10, and 12 are closed thereby delivering 
a high output signal to NOT gate 40 which in turn will generate a low 
output to OR gate 38 resulting in a zero output therefrom. Thus, the 
transmitter 4 will transmit a periodic signal of the type produced by 
cycle timer 26. The periodic signal will be received by the monitoring 
unit C via receiver 52. Receiver 52 directs the periodic carrier signal to 
amplifier 72. The amplified periodic signal is then directed to timer 74. 
It will be obvious to one of ordinary skill in the art to vary the time 
period of the timer 74 to accommodate various needs of an individual. In 
the preferred embodiment timer 74 has a twenty second time interval. If a 
periodic signal is received within twenty seconds, the timer 74 is reset. 
As previously stated, the monitored unit B transmits a periodic carrier 
signal at least every sixteen seconds. Thus, timer 74 will be continuously 
reset as long as monitoring unit C receives the periodic carrier signal. 
Thus, timer 74 produces a zero output and loss of signal indicator 44 
remains unlit. 
The output of amplifier 72 is further directed to NOT gate 88. The output 
of NOT gate 88 is directed to a five second timer 90. Timer 90 measures 
the length of the carrier signal produced by monitored unit B. During the 
time interval where no unmodulated carrier signal is being transmitted NOT 
gate 88 receives a low input and in turn provides a high output. The timer 
90 is designed to activate upon receipt of a low output. Thus, while no 
carrier signal is produced, timer 90 is dormant. Upon receipt of the 
periodic modulated signal transmitted by monitored unit B, NOT gate 88 
generates a low output and thus triggers timer 90. During normal 
operation, the timer 90 will reset before timing out since the periodic 
signal is only transmitted for a period of one second. 
During normal operation, the automatic gain control signal will be greater 
than or equal to the preset signal and thus result in zero or minimum 
output from comparator 84. Although the output from amplifier 72 directed 
to a first input of AND gate 76 is high, the second input of AND gate 76 
from the output of comparator 84 is low and will ensure that the child too 
far indicator 46 remains unlit. 
Finally, amplifier 106, during normal operation, will receive a zero input 
resulting in no output. Therefore, alarm indicator 50 will remain unlit. 
The monitoring unit C monitors the object wearing the monitored unit B to 
determine whether several alert/alarm conditions are present. These 
alert/alarm conditions include a first condition where the object has 
travelled beyond a predetermined distance, a second condition where the 
monitoring unit is no longer receiving a signal from the monitored unit B, 
a third condition where the monitored object has been immersed in water, a 
fourth condition where the monitored unit B has been removed from the 
object, and a fifth and final condition where the object manually 
activates an alarm. 
The operation of the monitoring apparatus A in the first condition will be 
hereinafter discussed. When the object wearing the monitored unit B has 
travelled a distance greater than a predetermined distance the automatic 
gain control signal will be less than the signal produced by the preset 
mechanism 85. Thus, comparator 84 will produce a high output and direct it 
to the second input of AND gate 76, AND gate 76 will produce an output 
since the first input is high due to the signal of amplifier 72. Indicator 
46 will illuminate informing the operator that the monitored object has 
exceeded a predetermined distance. Further, the output of AND gate 76 is 
directed to OR gate 80 which will generate an output to amplifier 82. The 
output of amplifier 82 will activate alarm 64. Thus, the operator receives 
both visual and audio alarms. The operator through switch 66 can 
deactivate audio alarm 64. As previously mentioned, the value of the 
signal produced by the preset mechanism can be varied, therefore, an 
attendant can readily vary the range for his/her specific use. 
The operator, upon observing the illumination of indicator 46 or the 
activation of audio alarm 64, will activate reset transmitter 54 which 
will in turn transmit a signal from the monitoring unit C to the monitored 
unit B. 
The monitored unit B will receive the signal via receiver 6. The reset 
transmitter signal will be directed to bistable multivibrator 28 and will 
cause the same to switch from low to high output & vice versa. The high 
output from bistable multivibrator 28 will result in OR gates 30 and 32 
producing a continuous output. Thus, transmitter 4 of monitored unit B 
will transmit a continuous signal to the monitoring unit C. The continuous 
signal produced by the monitored unit B will be directed through amplifier 
72 to NOT gate 88. The continuous carrier signal 88 causes the output of 
NOT gate 88 to be low and thus activate timer 90. If the continuous signal 
is generated for longer than five seconds, the timer 90 will time out and 
generate a high output to a first input of OR gate 92. The output of OR 
gate 92 will trigger indicator 94 informing the operator that the 
monitoring unit is in the search mode. Simultaneously, the output from OR 
gate 92 is directed through amplifier 96 to search relay 98 thereby 
energizing the search relay 98. The search relay 98 couples directional 
antenna 58 to receiver 52. The automatic gain control signal is amplified 
through inverting amplifier 100. The directional meter 60 readily enables 
the operator to determine at which orientation the directional antenna 
provides the highest or strongest output for a given signal. Thus, the 
operator is readily able to determine the direction in which to proceed to 
find the object wearing the monitored unit B. 
It will be appreciated by one of ordinary skill in the art, that the 
circuitry could be adapted to provide the operator with an approximation 
of the distance between the monitored and monitoring units. 
The monitored unit is designed to produce an alarm signal when any of the 
following alert conditions are present. These alert conditions include: 
manual activation of an alarm by the person being monitored, the monitored 
unit has been immersed in water, and the monitored unit has been taken off 
the monitored object. Switch 8 senses whether something has attempted to 
remove the monitored unit from the monitored object. Pressure switch 10 
senses whether the monitored object has been immersed in water and switch 
12 is the manual alarm. As explained earlier, upon opening of any of the 
aforementioned switches, the transmitter 4 of the monitored unit B 
broadcasts a continuous modulated signal to the monitoring unit C. The 
modulated signal can be either AM or FM depending upon the user's specific 
application. Receiver 52 receives the modulated signal and directs it to 
the input of amplifier 106. The output of amplifier 106 is directed to 
indicator 50 thereby illuminating the same. This informs the operator that 
either the monitored object has activated the manual alarm, the monitored 
unit has been immersed in water, or someone has tried to remove the 
monitored unit from the monitored object. The output of receiver 52 is 
simultaneously directed to OR gate 92. The output of OR gate 92 energizes 
search relay 98 and thereby coupling directional antenna 58 to receiver 
52. In this manner, the homing mechanism of the monitoring unit C is 
automatically energized. Additionally, the receiver 52 is connected to 
amplifier 108 which in turn triggers audio alarm 64. An operator may 
deactivate the audio alarm 64 via switch 68. 
The frequencies of the signal transmitted by the transmitter 4 of the 
monitored unit B must differ from the frequency of the signal transmitted 
by transmitter 54 of monitoring unit C in order for receivers 6 and 52 to 
receive the appropriate signal. The particular frequencies should be 
chosen to comply with FCC regulations. The preferable range of the 
monitoring apparatus A is a quarter of a mile. It would be obvious to one 
of ordinary skill in the art to vary the transmitters and receivers of 
monitoring unit C and monitored unit B to increase or decrease the 
specific range of the units as desired. 
The present invention provides a novel apparatus for monitoring persons, 
pets, things and the like. The present invention is able to significantly 
reduce the drain on the power source by transmitting a periodic signal as 
opposed to a continuous signal while threshold conditions are present. 
However, the present invention is readily adaptable to provide a 
continuous signal when at least one of a plurality of alarm/alert 
conditions are present. The continuous signal enables the homing mechanism 
of the monitoring unit to readily determine the direction needed to travel 
to locate the monitored object. Further, the monitoring apparatus of the 
present invention is able to more precisely define the activities of the 
monitored object which have led to the alarm/alert conditions. This 
enables the operator to readily reduce the possible areas of search and 
thus enable the operator to more readily find the monitored object. 
Finally, the present invention has developed a homing mechanism which is 
automatically actuated by receipt of either a modulated alarm signal or a 
continuous carrier signal produced by the monitored object. 
While this invention has been described as having a preferred design, it is 
understood that it is capable of further modifications, uses, and/or 
adaptions of the invention following in general the principal of the 
invention and including such departures from the present disclosure as 
come within the known or customary practice in the art to which the 
invention pertains such as maybe applied the essential features set forth 
and fall within the scope of the invention and of the limits of the 
appended claims.