Note: Descriptions are shown in the official language in which they were submitted.
2119955
FLYING INSECT TRAP USING
REFLECTED AND RADIATED LIGHT
Field of the Invention
The inventicn relates to an illuminated trap adapted
to attract flying insE~cts and immobilize the insect
within a trap hcusing. The trap uses a source of
attractant light in combination with a preferred
enclosure or housing configuration to increase the
capture rate.
A number of flying insect traps using attractant
light sources have been proposed in the prior art. The
Insect-0-Cutor fly traps made by I-0-C use an exposed
bulb with a high voltage electrocuting systems. Pickens
and Thimijan disclose exposed UV-emitting light sources
and electrified grids for trapping and electrocuting
flying insects. Another trap system generally uses
frontally or horizontally exposed ultraviolet black
lights for attracting insects to the trap. In the trap
the insect lands on an electric grid in the rear of the
cabinet. The grid provides a low voltage pulse that
causes the insect to fly down onto a nontoxic adhesive
trapping board. The captured insect can then be
disposed with the removable adhesive sheet. Grothaus et
al., United States Patent No. 4,696,126, discloses an
exposed bulb adhesive trap. Lazzeroni, Sr. et al.,
United States Design Patent No. 325,954, discloses a
generally front facing exposed bulb trap. Aiello et
al., United Status Patent No. 4,959,923, is related to
Lazzeroni, Sr. et al., United States Design Patent No.
325,954, using ultraviolet light source pulsed
electricity to stun insects and an adhesive trap.
Similarly, Gilbe:rt insect light traps use exposed bulbs
and generally fr~~nt facing entry spaces for fly trapping
purposes. Holli:ngsworth and Hartstack, Jr. disclose
;s5 data relating to the efficiency of a variety of
components of ex~~osed bulb fly traps.
Larkin, Unity=d States Patent No. 4,949,501, and the
ARP Venus Flylit~~'~ system disclose an attractant light
source. The light source and its housing are hinged on
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a wall attachment means such that the unit can be used
in a vertical mode wherein the light source is parallel
to the vertical surface and is placed at an angle of 90°
to the horizontal surface perpendicular to a vertical
surface. In this so called invisible mode, used during
business hours, the trap is designed to maintain the
operational components of the fly trap away from the
detection. The fly trap can be placed in a "turbo" mode
wherein the light source and housing are perpendicular
to the vertical surface and horizontal to the floor (or
at an angle greater than 90° to the vertical surface)
thus exposing the light directly to view at the
installation site which is asserted to increase insect
attraction.
White, United States Patent No. 4,876,822, discloses
a flying insect unit comprising a rectangular housing
enclosing a light source and an adhesive trapping
surface. The housing components are either parallel to
or perpendicular to the vertical mounting surface.
In our work modeling light attractant fly traps, we
have found the geometry of these prior art light traps
neither display the attractant light to the maximum
advantage nor use an improved trap insect entry
geometry.
Bri~af Discussion of the Invention
We have developed. a trap comprising a housing
surrounding a light source, the housing containing a
trap positioning means or mounting means for a vertical
surface and a pest immobilization surface. We have
found that the geometry of the housing of a fly trap
surrounding an attractant light source can enhance
flying insect capture rates. We have found that an open
upwardly facing entry area, and an reflective surface
angled to the horizontal surface cooperate with a source
of attractant light to substantially increase fly
capture rates. The flying insect traps of this
3
invention are adjacent to or mounted on a vertical
surface or horizontal. ceiling surface, typically a wall
or ceiling wherein the angled walls of the fly trap
housing provide an upwardly facing, top-sided entryway
for walking or flying entrance of insect pests and
further provide direct radiation of light, the
reflection and diffu~~ion of the attractant light from
the source onto the vertical surface or ceiling surface
in an effective and efficient attracting light display.
We have further found that colors contrasting to the
vertical surface or ceiling surface used in the exterior
of the housing or enclosure cooperate with colors of the
adjacent surface on which the fly trap is mounted to
increase capture rates.
Brief Description of the Drawings
FIGURE 1 contains views of the fly trap showing the
cooperative association of the light source, the
housing, the reflective surface, the immobilization
surface and the mounting means.
FIGURE 2 is a cross section of Figure 1.
Detailed Description of the Invention
The reflected light insect trap generally comprises
a housing operatively attached to a light source, an
insect immobilization surface and a positioning means.
We have found that light from the light source
radiates and re~flect;s directly from the upwardly facing
opening of the trap into a space generally and onto wall
surfaces and ceiling surfaces above the trap. Further,
the reflecting surface directs reflected light onto the
vertical surface or ceiling surface to further increase
capture rates. The light source useful in the fly
trap of the invention comprise a source of ultraviolet
light. Such light sources are commonly incandescent or
fluorescent electrically driven light sources that can
emit a broad spectrum of wavelengths but are primarily
4
optimized to emit ultraviolet light. For the purposes
of this invention ultraviolet light comprises radiation
having wavelengths between about
400 ~ and 40 ~ that has been found to be attractive to
flying insect species. The light sources commonly
provide from about 0.5 to about 100 watts of light
output, preferably the lights provide from about 0.5 to
about 75 watts. Preferred light sources are fluorescent
having from about 1 to about 40 watts per tube unit.
The trap can use a single source or two or more sources
horizontally or vertically arranged in the housing. The
units can be designed for service or household power or
for battery power using electronic conversion circuits
adapted to drive the light source. The light source can
be mounted within the housing with standard plug-in
units.
The light source is substantially enclosed within a
housing having an internal surface at least partially
covered with a reflective layer. The housing encloses
the light source or sources but provides a substantial
upwardly facing opening f.or the walking or flying entry
of flying insect pests. The housing is commonly made
from commonly available structural materials including
thermoplastics such as polyethylene, polypropylene,
polyethyleneterephtha.late; metallic materials such as
aluminum, magnesium or related alloys; wood or wood
products; reinforced thermoplastics or thermosetting
materials; paperboard, pressed paperboard, corrugated
paperboard, and others.
The interior of the housing contains a reflective
layer and is at least. partially reflective. Such
reflective layers can be made from shiny metallic
surfaces such as aluminum foil, metallized polyester
bright-white reflected panels, silvered glass mirrors or
other related reflective surfaces.
The housing also can contain an insect
immobilization means. For the purpose of this invention
5
the term insect immobilization means includes any device
or surface that can prevent flies from exiting the fly
trap after entry. Such immobilization means can include
pesticides in the form of a surface, layer or trap,
active and passive mechanical traps, liquid traps into
which the flies become immersed, adhesive layers,
pressure sensitive adhesive layers, high or low, D.C. or
pulsed voltage electric grids, or other such means that
can trap, immobilize, kill or dismember the insect
pests.
A preferred immobilization means for the purposes of
this invention comprises an adhesive surface. The most
preferred surface comprises a highly tacky pressure
sensitive adhesive surface. One useful adhesive is the
Tangletrap adhesive made by the Tanglefoot Co. Such a
surface, installed within the housing below the light,
is positioned such that the preferred entry way for
flying insect pests through the top opening is in an
optimal location for the entering insect pest to first
come to rest directly on 'the adhesive surface.
The traps of this invention can include an insect
attractant chemical. Insect attractant chemicals are
typically organic material that are at least somewhat
volatile and are products arising from typical insect
food sources or are a. pheromone or a mixtures of
pheromones.
The insect trap can also contain an effective amount
of an insecticide. A variety of volatile and non-
volatile insecticides and formulated insecticide
compositions are known to be effective against flying
insects and most can be used. However, the preferred
insecticides for use with this invention are nonvolatile
formulated insecticide compositions that kill insect
pests upon contact. Such nonvolatile pesticide
compositions are not released into the environment
surrounding the fly trap. Such materials include
pyrethroid and organophosphate insecticide compositions.
6
The preferred mode of construction of the insect
trap of the invention involves the geometry of the
reflecting surfaces in the insect trap. We have found
that the housing in the prior art having both vertical
or horizontal surfaces have some capacity for insect
attractancy. However, we have found that an improved
geometry of the housing can substantially and
surprisingly increase the attractancy of flying insect
pests. We have constructed insect traps having an
upwardly facing opening and side walls positioned at an
angle to the horizontal surface of less than 90°,
preferably less than 80°. Such a slanted reflective
surface, we have found, reflects and displays the light
fromathe light source on the vertical mounting surface
in a highly effective pattern that can substantially
increase attractancy and capture rates. We have found
that the attractancy of such devices peaks at an angle
of 45-75°, preferably about 60° between the reflecting
surface and the horizontal surface.
The insect traps of the invention having an upwardly
facing opening can have contaminating materials enter
through the opening or can invite misuse resulting from
objects thrown into the opening. In order to protect
the trap from.such problems, a barrier to such misuse
that does not prevent the entry of insects or the direct
or reflected radiation of light from the trap can be
installed on the upwardly facing opening. Such barrier
must substantially maximize the open area of the
upwardly facing opening and provide a minimal entry
barrier. For the purpose of this invention, grids or
screens having a dimension sufficiently large to permit
entry of insects but exclude objects that are thrown or
otherwise directed into the upwardly facing opening can
be excluded. Such screens or grids can be made from a
variety of materials including transparent or opaque
materials. Such materials include metallic wires,
synthetic or naturally occurring fiber threads,
~.~..~.~~5~
thermoplastic grids, expanded metal, wire screens, etc.
The insect trap of the invention can be placed on a
horizontal surface adjacent to a vertical surface or a
ceiling surface or can be mounted directly on a vertical
surface or ceiling surface. Correct placement increases
insect capture through direct radiation of light and
reflection of light onto either a vertical or horizontal
surface (ceiling). The insect traps of the invention
can be placed on horizontal surfaces adjacent to the
vertical surfaces or adjacent to ceiling surfaces in the
use locus. Once placed in such locations, the fly traps
are placed adjacent to such surfaces at a distance such
that light from the traps are radiated onto or reflected
onto the vertical surface or the ceiling surface.
Further, the traps are placed such that the contrasting
trap color to the vertical surface can aid in increasing
capture rates. Accordingly, when placed into the
environment, the traps are typically wall mounted or
placed within 30-50 inches of the vertical surface or
the ceiling surface or less. When placed in the use
environment, the mounting means includes a mechanical
system that can support the weight of the trap and can
maintain the upwardly open entry for insects. Such
traps can .fixed in place using a variety of mounting
hardware such as screws, bolts, nails, clips, flanges,
etc. or can be temporarily placed in the use locus using
velcro fasteners, pressure sensitive adhesive pads,
rubber feet, etc. Commonly available mounting means can
be used for fixing th.e insect trap on a vertical
surface. The housing can contain a flange, tab or hook
that can interact with the vertical surface holding the
trap in place using fasteners such as screws, nails,
permanent structural adhesives, velcro, etc.
Additionally, the fly traps can be suspended from
ceilings and can rest against the vertical surface using
suspending straps, cables, chains, etc. Alternatively,
the attachment means can comprise an aperture in the
housing that permits the f~.y trap to hang on cooperative
hooks, protrusions or other suspension points.on the
vertical surface. The important characteristic of the
mounting means for the fly trap is that the trap be
securely mounte~3 on the vertical surface such that the
vertical surface or wall receive an insect attractive
display of diffused and reflective light from the trap
to increase capture rates. Additionally, the wall can
act to define t:he upwardly facing opening of the fly
trap. The housing can entirely enclose the illumination
source or can enclose the illumination source on three
sides using the vertical surface to complete the
enclosure. T:he illumination source can be mounted
directly to the housing or can be mounted on the
vertical surface surrounded by the housing. Preferably,
the light source is mounted on a support attached to the
housing. The support can be mounted in any portion of
the housing, however, preferably the light source is
mounted on portions of the insect trap adjacent to the
vertical surface. The light source is then positioned
optimally to direct a substantial proportion of the
radiated energy onto the reflective surface. The light
is then reflected from the angled reflective surfaces
onto the vertical surface above and to either side of
the insect trap.
Similarly the immobilization surface can be fixed in
any location within the housing. The immobilization
surface is preferably placed in a location within the
housing where the immobilized insect pests are hidden
from view. Preferably, the immobilization surface is
placed directly opposite the upwardly facing opening.
Walking or flying insect pests then entering the trap
from above will be directed by the light source to the
bottom portion of they light trap containing the
immobilization surface. The immobilization surface is
preferably installed across a portion of the bottom, the
entire area of the bottom of the light trap and can
~:1.~_q~'S~~
9
additionally continue upwardly onto the curved surfaces.
Clear or pigmented white adhesives, preferably pressure
sensitive adhesives, can be used which will cooperate
with the reflecting surfaces of the angled side walls to
aid in directing reflected light onto the vertical
surface.
The insect trap housing of the invention typically
comprises a reflecting surface that reflects light onto
a vertical surface or a ceiling surface adjacent to the
trap to increase capture rate. The reflecting surface
can have a variety of configurations with respect to the
light placement. The lights can be positioned
vertically with respect to the reflecting surface such
that the light is above the highest projecting portion
of the reflecting surface, can be approximately equal to
the height of t:he projecting surface or can be
substantially below the high point of the reflecting
surface. In th~~ instance that the light source
comprises multiple sources, the reflecting surface
discussion relates to the highest source in the housing
configuration. A housing designed for placement on a
horizontal surface in close relationship with the
vertical surface can take a variety of shapes. The
insect trap can be generally circular, oval,
ellipsoidal, ca:n be an extended shape having parallel
sides and either rectilinear or curved ends, the trap
can be triangular, square or rectangular, hexagonal,
octagonal, etc. However, it is important to maintain in
each trap confi~~uration the angled reflective surface to
maintain reflection of light. The reflection surface
can be the exterior wall of the trap or can be a surface
installed within a vertical wall or a wall mounted at an
angle other than the angle of the reflected surface. In
other words, th~a exterior wall of the housing can be at
any arbitrary angle to other housing components and a
horizontal surface as long as an internal surface within
the housing is :positioned at the desired angle for the
10
reflecting surface. When the trap of the invention is
mounted on a vertical surface such as a wall, it can be
mounted at virtually any height. Typically, the side of
the fly trap adjacent to the vertical surface is
configured to match the vertical surface. The most
common vertical surface present in most use loci is a
flat vertical surface.
Preferably, the insect trap of the invention is
installed in a .Location with a high concentration of
insects at or above eye level permitting the
installation of the illumination source to reside at the
top, inside of i:he housing adjacent to the vertical
surface.
Tie insect i~rap of the invention can be manufactured
in a variety of ways. The traps can be molded from
thermoplastic materials or can be assembled from flat or
substantially planar components that are attached using
commonly available fasteners to form the angled side
walls and the f:Lat bottom. Once a housing is assembled
that can be mounted on a wall such that the light
sources are sub:~tantially enclosed, the mounting
hardware can be introduced onto the housing with the
appropriate insl~allation of the immobilization surface
and the light source. The insect traps of the invention
can be hardwired in place, can be empowered using
electrical cord; or can have batteries installed at
available locations in the housing.
Experimental Section
In the deve:Lopment of the insect traps of the
invention, a substantial body of work was conducted to
discover the in;~ect trap geometry that would provide
peak capture rates for flying insects. We found that
insect pests enter the trap either by alighting on the
vertical surface and entering the trap by walking or by
flying directly into the insect trap alighting on the
first available surface. We have found that using
either mode of entry, the most likely direction of entry
11
will be vertica~_ly into an upwardly facing trap.
Accordingly, we have :found that it is highly desirable
to avoid placing any substantial barrier in the flying
insect trap that: would prevent entry from above. No
barrier should be placed to impede insects from walking
down the vertical surface into the trap. The light
sources should not be substantially virtually obscured
by any portion of the housing. Grids or screens
installed i.n the housing should have minimal barrier
properties. Further, in illuminated traps, we have
found that there is a substantial increase in capture
rates if the rei=lective surface in the trap is not fixed
at an angle that: is parallel or perpendicular to the
vertical mounting surface. We have found that such a
configuration substantially reduces the efficiency of
the attractant ~_ight because the light is not adequately
displayed to thE: insects causing attractancy. Further
we have found that the bare light sources, while they
are bright, do not attract the insects as well as a
combination of direct radiated light and a diffused
display of reflective light on the vertical surface. We
have also found that the use of a contrasting color,
generally a dar~;er co:Lor, in the trap housing to the
color of the vertical surface increases capture rates.
In conducting capture rate experiments, the fly
traps of the invention are installed in an appropriate
location in a room having white walls and ceiling, 50~
relative humidity, insect food, competing fluorescent
lights, and a dE:nsity of approximately one fly per each
10 cubic feet oj: room space. The fly density was
optimized to reduce statistical noise in experimental
results. The mE~an data represent the mean number of
flies captured per each one half hour. A prototype trap
was installed iii the experimental room in order to
determine the impact on capture rates resulting from
trap modification including the opening of the trap
facing in a variety of directions. Traps were installed
12
with openings upwardly directed, downwardly directed and
horizontally directed. Statistically significant
differences betv~~een the upwardly "open" configuration
and all other canfigur_ations which are called "closed"
were found (Table 1). The use of an upwardly facing
opening had a strong increase on mean capture rates and
resulted in. greater than a 40~k increase in fly capture
rates when a trap having an upwardly facing opening was
installed on a vertical surface. The control experiment
in the following tablEa comprises a flat bottom housing
having no side smalls surrounding the exposed bulbs.
TABLE 1
Top Eptry
Conficturation R~licates Mean* Std. Dev.
Open 12 23.083 6.067
Closed 12 16.417 5.017
Control 4 22.000 4.163
* Mean fly capture rate
13
Experiments were also conducted to determine the
best angle at which a reflective surface is placed.
Tables 2 and 3 show the housing geometry that were used.
The housing ang:Le relates to the angle between the
housing wall anti the horizontal surface.
TABLE 2
Housinq Anqle Replicates Mean Std. Dev.
Control 3 15.3 6.7
Thirty Degr. 3 17.3 3.5
Sixty Degr. 3 19.7 2.5
Ninety Degr. 3 12.3 3.1
TABLE 3
Housinq Anqle Replicates Mean Std. Dev.
Thirty Degr. 12 18.0 5.3
Sixty Degr. :12 23.6 5.9
These data :>how that the capture rate using
reflecting surfaces at 30° or 60° angles are
significantly better than a 90° surface. Further, the
60° surface is significantly better (by 315) than the
30° surface in increased capture rates.
Table 4 shown below displays mean capture rates
measured in flies per half hour and shows that a
contrasting dark: color significantly increases the
capture rates fc~r the fly trap installations. These
data show that :~ignif:icantly more insects (greater than
34~) are attracted to a contrasting color in the housing
exterior.
14
TABLE 4
Trap Color Count Mean Std. Dev.
White 2'7 19.4 5.4
Tan 12 26.0 5.8
Further experiments were done to compare the effect
of the installation of the shiny metallized polyester
(Mylar) reflective surface within the housing with the
effect of a non--reflecting surface. The results of the
experiment are :chown below in Table 5.
TABLE 5
Interior Housing Surface Count Mean Std. Dev.
Blacks 13 18.6 5.6
Metallized MylarZ 13 23.5 7.5
Our experimentation shown in Table 5 demonstrates a
substantial increase :in capture rates when a shiny
reflective surface is installed within the housing. The
metallized Mylar. surface we have used shows a
substantial. increase (by 26$) in capture rates when
compared to a b7_ack non-reflective surface. The capture
rates resulting from the use of a black surface is an
indication that the direct radiation of light from the
light source through the upwardly facing opening is a
substantial attractant effect.
Deta9.led Discussion of the Drawings
Figure 1 shows views of the preferred fly trap of
the invention. The f:ly trap comprises mounting means 10
comprising a bracket portion of the housing. Such
brackets can be screw attached to the vertical surface
20. The housing displays an internal reflective surface
11 comprising an aluminum foil or metallized polyester
Non-reflective black surface
Reflective
15
surface. The internal housing surface contains a
pressure sensitive adhesive surface 12 positioned below
the light sourcE~ or illumination units 16 opposite to
the upwardly facing opening defined by the top 13 of the
walls 19 of the housing. The external walls 19 of the
housing are coni:igured at a 60° angle to the horizontal
surface 20 to optimize the area of ingress and to
optimize the rei_lected display of light on the vertical
surface from thE: fly 'trap. The exterior of the housing
19 displays a color contrasting to the color of the
vertical surface' 20. The illumination units 16 are
fluorescent ultraviolet sources in sockets 17 that are
commonly attached to household or service power. The
adhesive surface 12 rests upon a bottom portion 18 which
is a part of the housing 19. The fly trap is mounted on
a vertical surface 20 such that the illumination units
16 are not directly viewed by an occupant of the
installation locus. i~ ballast (not shown) can be placed
in the housing beneath the adhesive 12.
Figure 2 shows a cross section at 2 in Figure 1.
The insect trap of them invention can be mounted on the
vertical surface using mounting means 10 which in Figure
2 comprises a bracket and screw device. The trap is
made using the.housing 19 with an angled reflective
surface 21 that aids .in directing reflected light onto
the vertical surface :?0. The illumination sources 16
are positioned within the housing to radiate light
through the upwardly facing opening 24 and onto the
reflecting surface 21. Adhesive surface 12 rests upon a
horizontal housing surface 22.
While the above specification, data and Figures
provide a basis for understanding the advantages of
using the disclosed gE:ometry in illuminated insect
traps, many embodimeni~s of the invention can be made
without departing frorn the spirit or scope of the
disclosure herein. For that reason, the invention
resides in the claims hereinafter appended.
