Detection apparatus for safety eyewear

A detection apparatus for monitoring specified safety eyewear being worn by persons who are either passing into or are located in the designated area which requires that a person in the area be wearing the specified safety eyewear. The detection apparatus includes an infrared reflector which is located on the specified eyewear, an infrared transmitter for transmitting a beam of infrared radiation towards the person, an infrared receiver which receives reflected radiation from the infrared reflector on the safety eyewear being worn by the person and an alarm which is normally inactive and which remains inactive as long as infrared radiation from the transmitter is reflected back to the infrared receiver from the reflector. The alarm is activated when infrared radiation is transmitted to the person and not reflected to the receiver due to the absence of specified safety eyewear which contains the appropriate infrared reflector.

BACKGROUND OF THE INVENTION 
The present invention relates generally to a detection system for 
monitoring specified safety eyewear being worn by individuals for whom the 
wearing of such eyewear is required in certain circumstances. The 
invention is specifically directed to the apparatus for detecting 
specified safety eyewear being worn by persons who are passing through an 
entryway into a designated area which requires that persons who are in the 
area are wearing the specified safety eyewear and for sounding an alarm 
when the specified eyewear is not detected on a person who is passing 
through the entryway into the designated area. The invention is also 
specifically directed to a detection system for preventing the starting of 
electrically driven machinery by a person who is not wearing the 
designated eyewear for that machine when attempting to start the machine. 
Many types of detection systems have been developed for detecting persons 
who are approaching or passing through entryways to specified areas. More 
specifically, detection systems have been developed for discriminating 
between persons who are authorized to enter a specified area and those who 
are not. One such system discriminates between a person who is wearing a 
small metal object and a person who is not. This system can only be used 
in circumstances where the wearing or not wearing of a small metal object 
is tightly controlled such as in certain types of institutions. Another 
type of detection system provides a warning if the fastener of a garment 
which is worn by a person is not properly fastened in an environment where 
the fastener must be closed to ratify safety or sanitary requirements. 
None of the prior art detection systems are capable of detecting safety 
eyewear or distinguishing safety eyewear from conventional eyewear. Up to 
the present time, the monitoring of the wearing of specified safety 
eyewear by persons entering a designated area or for operating a 
designated machine is accomplished by visual manual inspection. A full 
time guard must be employed at the entryway to a designated and supervisor 
in a work area must maintain a constant visual to ensure that safety 
eyeglasses are worn by operators of certain types of machinery. In spite 
of extensive education and the proper use of safety eyewear and the threat 
of disciplinary action for violation of safety eyewear policies violations 
of eyewear safety policies continue to occur throughout industry. These 
violations inevitably lead to eye injuries. The slight inconvenience of 
wearing proper safety eyewear is a small price to pay to avoid the pain 
suffering and loss of production for an individual who had sustained an 
eye injury due to the failure to wear proper safety eyewear. Even if the 
individual is conscientious about using proper safety eyewear most of the 
time this is all negated when an injury occurs during one careless moment 
when a person forgets to have his or her safety eyewear when entering a 
designated area or is in a hurry or only intends to stay in the designated 
area for a short time. 
These and other difficulties experienced with the use of safety eyewear in 
industry have been obviated by the present invention. 
It is, therefore, a principal object of the invention to provide an 
automatic detection system for safety eyewear which will sound an alarm 
when a person who is not wearing the specified eyewear attempts to enter a 
designated area within which use of such eyewear is required. 
Another object of this invention is the provision of an automatic detection 
system for safety eyewear which will detect the wearing of specified 
safety eyewear by persons of different heights who are entering a 
designated area within which use of such eyewear is required. 
A further object of the present invention is the provision of an automatic 
detection system for specified safety eyewear which is being worn by a 
person who is operating an electrically driven machine for which the 
wearing of specified safety eyewear is required when operating the 
machine. 
It is another object of the present invention to provide an automatic 
detection system for specified eyewear which is being worn by a person who 
is operating an electrically driven machine which prevents the machine 
from being started by a person who is not wearing the safety eyewear which 
is specified for that machine. 
A still further object of the invention is the provision of an automatic 
detection system for specified safety eyewear which is being worn by a 
person who is operating an electrically driven machine which cannot be 
started by a person who is not wearing the specified eyewear and which 
will automatically shut off when that person leaves the machine. 
With these and other objects in view, as will be apparent to those skilled 
in the art, the invention resides in the combination of parts set forth in 
the specification and covered by the claims appended hereto. 
SUMMARY OF THE INVENTION 
In general, the invention consists of detection apparatus for monitoring 
specified safety eyewear being worn by a person who is entering a 
designated area which requires the wearing of such eyewear. The detection 
apparatus comprises an infrared reflector which is fixed to the designated 
eyewear, an infrared transmitter and an infrared receiver which are 
located at one side of an entryway to the designated area and an alarm 
system which is activated when a person not wearing the specified eyewear 
attempts to pass through the entryway into the designated area. When a 
person who is wearing the specified safety eyewear enters the entryway, 
infrared radiation from the transmitter will be reflected back to the 
receiver from the infrared reflector of the specified eyewear so that the 
alarm which is controlled by the receiver will not be activated. The 
invention also consists of a detection apparatus for monitoring specified 
safety eyewear being worn by a person who is located at a designated 
position for operating an electrically driven machine which requires the 
wearing of the specified eyewear during the operating of a machine. The 
detection apparatus comprises an infrared reflector on the specified 
eyewear, an infrared transmitter which directs infrared radiation toward 
the position which is being occupied by the machine operator, an infrared 
receiver which is located adjacent the infrared transmitter and control 
circuitry for the machine which is operatively connected to the 
transmitter and receiver so that the machine can only be operated by a 
person who is wearing the specified safety eyewear.

DETAILED DESCRIPTION OF THE INVENTION 
Referring first to FIG.'s 1-3 there is shown a first embodiment cf a 
detection apparatus of the present invention which is generally indicated 
by the reference numeral 10. The detection apparatus 10 is shown applied 
to an entryway 12 and comprises a transceiver 14 which is mounted on one 
side of the entryway 12. The transceiver 14 includes an infrared 
transmitter 16 which transmits a spreading beam 15 of infrared radiation 
to the opposite side of the entryway and an infrared receiver 18. The 
detection apparatus 12 also includes an electronic sensor, generally 
indicated by the reference numeral 25, for sensing the presence of a 
person in the entryway 12. The sensor 25 comprises a lamp 26 at one side 
of the entryway 12 and a photo receptor 28 at the opposite side of the 
entryway 12 for receiving a beam of light from the lamp 26. The photo 
receptor 28 is actuated when the beam of light, indicated by the reference 
numeral, 29 from the lamp 26 is interrupted when a person, indicated by 
the reference numeral 24, passes through the entryway 12. The detection 
apparatus 10 also includes an infrared reflector 22 which is mounted on 
the frame of protective eyewear 20 which is shown being worn by a person 
such as that which is worn by the individual 24 who is depicted in FIG. 1. 
The reflector 22 contains a material which reflects infrarred radiation. 
Excellent results have been obtained from a 3M material which is sold 
under the trademark reflexite and designated by the model numbers Ad1000P 
and AC/1000M. 
Only the proper safety eyewear which is specified for a designated area 
will contain the infrared reflector 22. When a person enters this 
designated area through the entryway 12, infrared radiation from the 
transmitter 16 will strike the infrared reflector 22 and will be reflected 
back to the infrared receptor 18. If the sensing means 25 senses a person 
in the entryway 12 and that person does not have proper safety eyewear 
which contains the infrared reflector 22, infrared radiation from the 
transmitter 16 will not be reflected back to the receiver 18. This will 
cause the receptor 18 to initiate the sounding of an alarm, not shown, 
which signals the arrival of a person into the designated area who is not 
wearing the specified safety eyewear for that area. 
Referring particularly to the electrical diagram of FIG. 3, the interaction 
of the various elements which make up the detection apparatus 10 is 
described in conjunction with FIG. 3. The lamp 26 and the photo receptor 
28 are located on lines 32 and 33 which are connected across a pair of 
power lines 27 and 29 from a source of electrical power 30. The 
transceiver 14 is located on a line 34 which contains a normally open 
contact 36 to maintain the transceiver 14 in a normally de-energized 
state. When a person enters the entryway 12, the beam of light from the 
lamp 26 is interrupted. This causes the normally open contact 36 of the 
receptor 28 to close, thereby completing a circuit across the power lines 
27 and 29 through line 34 and energizing the transceiver 14. The 
transmitter portion 16 of the transceiver transmits a beam of infrared 
radiation toward the other side of the entryway 12. If the person in the 
entryway 12 is wearing the specified safety eyewear, a portion of the 
infrared beam will strike the reflector 22 and be reflected back to the 
receiver portion 18 of the transceiver. If the person is not wearing the 
specified safety eyewear, no infrared radiation will be reflected to the 
receiver 18. This causes its normally open contact 40 on line 42 to close, 
thereby connecting line 42 across the power line 27 and 29 and energizing 
an alarm 38 which is on line 42. This will either remind the individual 
who set off the alarm of the need to wear proper eyewear or alert 
supervisory personnel that a person who is wearing improper eyewear has 
entered the designated area. 
Referring to FIG. 4, there is shown electrical diagram which illustrates a 
variation in the electrical controls and operation of the first embodiment 
of the present invention and is generally indicated by the reference 
numeral 10, The lamp 26 and the photo receptor 28 are connected to lines 
32 and 33 which are connected across the power lines 27 and 29 in the same 
manner as shown in FIG. 3. The transceiver 14 is located on a line 46 
which is connected across the power lines 27 and 29 so that the 
transceiver 14 is normally in an energized state. Therefore, the beam of 
infrared radiation from the transmitter portion 16 of the transceiver is 
transmitted continuously across the entryway 12. The alarm 38 is located 
on a line 44 which contains a normally open contact 48 and a normally 
closed contact 47. The alarm 38 is, thereby, normally in a de-energized 
state. The contact 48 is part of the internal circuitry of receptor 28. 
When the beam of light from the lamp 26 is interrupted by a person walking 
through the doorway 12, the photo receptor 28 closes the contact 48. If 
the person who interrupted the beam of light from the lamp 26 is wearing 
specified safety eyewear, infrared radiation from the transmitter portion 
of the transceiver 14 will strike the reflector 22 on the eyewear and will 
be reflected back to the receiver portion 18 of the transceiver. The 
transceiver 14 has a built in relay circuit which includes the normally 
closed contact 47 and is effective to open the contact 47 when reflected 
infrared radiation is received by the receiver 18. This will keep the line 
44 open and maintain the alarm 38 in the de-energized state. However, if 
the person is not wearing the proper protective eyewear, no reflected 
infrared radiation will be received by the transceiver 14 and the normally 
closed contact 47 will remain closed. Since the normally, open contact 48 
is also closed by the relay circuit of the photo receptor 28 the alarm 38 
will be energized to warn the person who is passing through the entryway 
12 and other supervisory personnel that a person is entering the 
designated area without wearing the specified safety eyewear or that area. 
Referring to FIG.,s 5, 6 and 7, there is shown a second embodiment of the 
invention which is generally indicated by the reference numeral 50. The 
detection apparatus 50 comprises the same electronic sensor 25 as for the 
first embodiment including the lamp 26 for transmitting the beam of light 
29 across the entryway 12 to the photo receptor 28. The detection 
apparatus 50 also comprises a first transceiver 52 which is located at one 
side of the entryway 12 and a second transceiver 56 which is located at 
the opposite side of the entryway. The first transceiver 52 comprises a 
transmitter 53 for transmitting a beam, 49, of infrared radiation to the 
opposite side of the entryway and a receiver 54 for receiving reflected 
infrared radiation. The second transceiver 56 comprises a transmitter 57 
for transmitting a beam, 55, of infrared radiation t the first side of the 
entryway and a receiver 57 for receiving reflected infrared radiation. 
Each infrared transmitter transmits a beam of infrared radiation which 
spreads vertically but is relatively narrow from front to back. The 
transceivers 52 and 56 are offset front to back as shown in FIG. 6 so that 
the beams from their respective transceivers are offset front to back. 
Therefore, the infrared radiation from one transmitter will not affect the 
receiver of the other transmitter. The safety eyewear which is to be used 
with the second embodiment 50, indicated by the reference numeral 64 in 
FIG. 8, is equipped two infrared reflectors 66 and 68 which are located on 
opposite sides of the eyeglass flame. 
The operation of the second embodiment 50 will now be readily understood 
with reference to the electrical controls which are shown in FIG. 7. The 
lamp 26 and the photo receptor 28 are located on lines 74 and 73, 
respectively, which are connected across a pair of power lines 71 and 72 
which are, in turn, connected to a source of electrical power 70. The lamp 
26 is on constantly for transmitting a continuous beam of light 29 to the 
photo receptor 28. The first and second transceivers 52 and 56, 
respectively, are located on a line 76 which also contains a normally open 
contact 75. This maintains the line 76 open and the first and second 
transceivers 52 and 56, respectively, deactivated. An alarm 78 is located 
on a line 80 which contains a pair of parallel normally open contacts 81 
and 82. The contacts 81 and 82 keep the line 80 open and maintain the 
alarm 78 in a deactivated state. The closing of ether of the contacts 81 
and 82 will complete a circuit across the line 80 between the power line 
71 and 72 to activate the alarm 78. The contact 81 is part of a relay 
circuit of the second transceiver 56. The normally open contact 81 forms 
part of a relay circuit of the first transceiver 52. When a beam of light 
from the lamp 26 is interrupted by a person walking through the entryway 
12, the photo receptor 28 is effective to close the normally open contact 
75 which forms part of the relay circuit of the photo receptor 28. The 
closing of contact 75 completes a circuit across the line 76 and energizes 
the transceivers 52 and 56 for transmitting beams of infrared radiation in 
opposite directions, as shown in FIG.'s 5 and 6. If the person who is 
passing through the entryway 12 is wearing proper safety eyewear 64, 
infrared radiation will be reflected from the reflector 66 back to the 
receptor portion 54 of the first transceiver 52 and infrared radiation 
will be reflected from the reflector 68 back to the receiver portion 58 of 
the second transceiver 56. When this occurs, the contacts 81 and 82 will 
remain open. However, if the receiver portion of either of the 
transceivers 52 and 56 does not receive reflected infrared radiation it 
will close its respective contact 81 or 82. This will complete a circuit 
across line 80 and energize the alarm 78. 
FIG. 9 shows a variation in the controls and operation of the second 
embodiment of the invention which is generally indicated by the reference 
numeral 50'. The controls for the variation 50' of the second embodiment 
are identical to the controls which are shown and described in FIG. 7, 
except that the normally open contacts 82 and 81 of the first and second 
transceivers 52 and 56 respectively are arranged in series on line 80 
which contains the alarm 78. In this variation, if only one transceiver 
fails to receive reflected infrared radiation, its corresponding contact 
81 or 82 on line 80 will be closed. However, the other contact on line 80 
which is controlled by the other transceiver will remain open as long as 
the other transceiver receives reflected infrared radiation from the 
corresponding reflector of the safety eyewear 64. If neither of the 
transceivers 52 and 56 receives reflected infrared radiation, both 
contacts 81 and 82 will be closed and the alarm 78 will be activated. 
Referring to FIGS. 10 and 11 there is shown a third embodiment of the 
detection apparatus of the present invention which is generally indicated 
by the reference numeral 86. The detection apparatus 86 is shown applied 
to an entryway 88 which is closed by a door 89. The door 89 is maintained 
in a normally locked state by means of an electrically actuated locking 
mechanism 96. The detection apparatus 86 comprises a transceiver 90 which 
is located at one side of the doorway and which includes an infrared 
transmitter 91 and an infrared receiver 92. When activated, the 
transmitter 91 projects a beam of infrared radiation across the entryway 
88 to the opposite side of the entryway. The detection apparatus 86 also 
comprises an electric sensor, generally indicated by the reference numeral 
95, which includes a lamp 93 at one side of the entryway 88 and a 
photoreceptor 94 at the opposite side of the entryway. The lamp 93 
projects a light beam across the entryway to the photoreceptor 94. The 
transceiver 90 and the sensor 95 are located sufficiently in front of the 
door 89 so that the light beam from the lamp 93 and the infrared radiation 
from the transmitter 91 will be interrupted by a person, as that person 
approaches the door 89. The door 89 is maintained in a normally locked 
state to prevent persons from entering the designated area beyond the 
door, unless the person is wearing specified safety eyewear. The locking 
mechanism 96 locks the door 89 against the adjacent door jam 97 and 
comprises a catch 98 which is recessed in the outer edge of the door and 
which has a bore 100 which faces the door jam 97. The lock 96 also 
includes a housing 102 which is recessed in the edge of the door jam and 
which faces the catch 98. The housing 102 contains a solenoid, generally 
indicated by the reference numeral 104, which includes a core 105 and a 
plunger 106 which is moveable relative to the core 105 toward and away 
from the bore 100 of the catch 98. When the solenoid 104 is in the 
de-energized state, a spring 108 maintains the plunger 106 within the bore 
100 to maintain the door 89 in the locked condition. When the solenoid 104 
is energized, the plunger 106 is drawn into the core out of the bore 100 
so that the door 89 is in the unlocked condition. 
The operation of the third embodiment 86 will be readily understood in 
conjunction with the electrical controls for the third embodiment shown in 
FIG. 12. 
Referring to FIG. 12, the lamp 93 and the photo receptor 94 are located on 
lines 109 and 110 which extend across a pair of power lines 112 and 113 
which are connected to a source of electrical power 114. The photo 
receptor 94 includes a relay circuit which includes a normally open 
contact 116 on line 115. The transceiver 90 is also located on line 115 
and is maintained in a de-energized state due to the open contact 116. The 
transceiver 90 has a relay circuit which includes a normally open contact 
120 on line 119. The solenoid 104 is also located on line 119 and is 
maintained in the deactivated state due to the open contact 120. When a 
person approaches the door 89 the light beam from the lamp 93 to the photo 
receptor 94 is interrupted. This causes the relay circuit of the photo 
receptor 94 to close the normally open contact 1-6. This completes a 
circuit across the line 115 and energizes the transceiver 90. The 
transmitter 91 of the transceiver 90 projects a beam of infrared radiation 
across the doorway 88. If the person who is approaching the door 89 is 
wearing specified safety eyewear, it has attached thereto an infrared 
reflector 117. The infrared radiation from the transmitter 91 strikes the 
infrared reflector and a portion of the beam is reflected back to the 
receiver 92. When the reflected infrared radiation is received by the 
receiver 92, its relay circuit is activated to close the normally open 
contact 120 to complete a circuit across the line 119 and thereby energize 
the solenoid 104. When the solenoid 104 is energized, the plunger 106 is 
drawn out of the bore 100, thereby unlocking the door 89. This allows the 
person to open the door and pass through the entryway 88 into the 
designated area behind the door 89. 
Referring to FIG. 13 there is shown a fourth embodiment of the detection 
apparatus of the present invention which is generally indicated by the 
reference numeral 122. The detection apparatus 122 comprises a transceiver 
124 which is identical to any of the transceivers in the previous 
embodiments and includes an infrared transmitter and an infrared receiver. 
The transceiver 124 is located on a line 126 which is connected across a 
pair of power lines 28 and 130 which are connected to a source of 
electrical power 132 through an electrical starting circuit, generally 
indicated by the reference numeral 133. The starting circuit 133 includes 
a spring return normally open push button switch 135 which, when 
depressed, bridges a pair of contacts 137 to connect the power line 128 to 
the source of electrical power 132. A line 139 bridges the contacts 137 
and contains a normally open contact 140 which keeps the line 139 open. 
The contact 140 is part of a relay circuit of the transceiver 124 which 
also includes a normally open contact 138 on line 136. A drive motor 134 
for the machine is also located on line 136 and is maintained in a 
normally de-energized state by means of the open contact 138. The 
transceiver 124 is positioned in relation to the machine so that it is 
located on one side of a position which is occupied by the operator of the 
machine when he or she is operating the machine. Therefore, the 
transmitter portion of the transceiver projects a beam of infrared 
radiation towards to the opposite side of the location which is normally 
occupied by the operator. The machine is started by pressing the push 
button 134 to bridge the contacts 137 and to complete a circuit across the 
line 126, thereby energizing the transceiver 124. Energization of the 
transceiver 124 will cause its transmitter to project a beam of infrared 
radiation toward the operator of the machine. If the operator is wearing 
safety eyewear which is specified for that machine, it will have an 
infrared reflector 142 which reflects the infrared radiation back to the 
receiver portion of the transceiver 124. This causes the normally open 
contacts 140 and 138 to close. Closing of the contact 138 completes a 
circuit across the line 136 to energize the drive motor 134 of the 
machine. Closing of the contact 140 closes the line 139 to effectively 
bridge the contacts 137 so that everything beyond the starting circuit 133 
is maintained energized when the push button 135 is released. If the 
operator of the machine is not wearing safety eyewear which is specified 
for that machine, no reflected infrared radiation will be received by the 
transceiver 124. Therefore, the contacts 138 and 140 remain open and the 
machine can not be started. If the operator removes the safety eyewear or 
walks away from the machine, reflected infrared radiation will not be 
received by the transceiver 124, thereby causing contacts 138 and 140 to 
open and causing the machine to stop. Since the contact 140 also opens, 
the circuit through the line 128 will be broken and the transceiver will 
be de-energized. The machine can only be restarted by the pushing of the 
start button 135 by a person who is wearing safety eyewear which is 
specified for the machine. 
Clearly, minor changes may be made in the form and construction of the 
invention without departing from the material spirit thereof. It is not, 
however, desired to confine the invention to the exact form herein shown 
and described, but it is desired to include all subject matter that 
properly comes within the scope claimed.