Air blowing device and insect trapping method

Provided is an air blowing device that makes it possible to safely improve insect trapping performance. The air blowing device 1 is provided with: a housing 2 comprising an inlet 20 and an outlet 5 for air; an air blower 10 arranged within the housing 2; a pre-filter 8 that is arranged in the inlet 20 and that collects dust within air; and a cover member 3 that comprises an air suction port 4, that is attached to the housing 2, and that forms an insect trap space 25 between the suction port 4 and the inlet 20. Insects that enter the insect trap space 25 via the suction port 4 are trapped. The outer surface of the cover member 3 is formed so as to have a dark color.

TECHNICAL FIELD

The present invention relates to an air blowing device that traps insects that have entered an insect trapping space between a housing and a cover member and to an insect trapping method.

BACKGROUND ART

Patent Document 1 discloses a conventional air blowing device. This air blowing device has a housing that has an opening as an air inflow port formed through a back surface thereof and an opening as an air blow-off port formed through an upper surface thereof. The housing is installed on a floor surface or the like in a room and includes an air blower therein. A filter that collects dust in air is arranged at the inflow port. On a back surface side of the housing, a cover member that covers the inflow port is demountably mounted with respect to the housing. The cover member has a plurality of openings each formed therethrough as an air section port.

In the air blowing device configured as above, upon a start of an operation, the air blower is driven to cause air to be sucked in through the suction port. The air thus sucked in through the suction port flows into the inflow port, and after dust is collected therefrom by the filter, the air is discharged to the exterior through the blow-off port. Thus, air in the room can be purified. Furthermore, cleaning of the filter is enabled by demounting the cover member from the housing.

According to the air blowing device of Patent Document 1 described above, dust in air is collected, and thus health hazards caused by dust or the like can be reduced. Furthermore, with a recent increase in health awareness, there is a growing demand for an air blowing device having an insect trapping function in order to reduce infectious diseases or the like transmitted by insects such as a mosquito.

An insect trapping device described in Patent Document 2 is provided with a housing having a front surface that is opened/closed with a door and a side surface that has an opening portion formed therethrough, an attraction light source that emits attraction light for attracting insects into the housing, and an adhesive insect trapping sheet that is arranged on a back surface of the door and traps insects.

In the insect trapping device configured as above, when the attraction light source is lit with the door closed, attraction light is emitted toward the exterior of the housing via the opening portion of the side surface. An insect enters the housing via the opening portion of the side surface and gets caught by the insect trapping sheet. Then, the insect trapping sheet thus used, to which a predetermined quantity of insects have adhered, is removed from the door, and an unused insect trapping sheet is attached to a predetermined position on the door. Thus, replacement of an insect trapping sheet can be performed.

LIST OF CITATIONS

Patent Literature

SUMMARY OF THE INVENTION

Technical Problem

According to the insect trapping device of Patent Document 2 described above, however, attraction light does not reach to a sufficient distance in a direction not facing the opening portion of the side surface, and thus there has been a problem that insect trapping performance is decreased. Meanwhile, mounting the attraction light source to an outer surface of the insect trapping device leads to a fear that attraction light might exert an adverse effect on a user's eyes.

An object of the present invention is to provide an air blowing device capable of safely improving insect trapping performance. Furthermore, another object of the present invention is to provide an insect trapping method capable of safely improving an insect trapping effect.

Solution to the Problem

In order to achieve the above-described objects, the present invention is characterized as follows. That is, an air blowing device is provided with a housing that has openings as an air inflow port and an air blow-off port, an air blower that is arranged in the housing, a filter that is arranged at the inflow port and collects dust in air, and a cover member that has an opening as an air suction port, is mounted to the housing, and forms an insect trapping space between the suction port and the inflow port, and the air blowing device is configured to tap insects that have entered the insect trapping space via the suction port. In the air blowing device, an outer surface of the cover member is formed in a dark color.

According to this configuration, the air blower is driven to cause air to be sucked in through the suction port, and dust in the air is collected by the filter, after which the air is discharged through the blow-off port. An insect is attracted to the cover member whose outer surface is formed in a dark color and enters the insect trapping space via the suction port provided through the cover member, thus being trapped.

Furthermore, in the present invention, preferably, in the air blowing device configured as above, a region of the housing, which faces the insect trapping space, is colored in a dark color.

Furthermore, in the present invention, preferably, in the air blowing device configured as above, the cover member is arranged behind the housing, and a front surface of the housing is formed in a bright color.

Furthermore, in the present invention, preferably, in the air blowing device configured as above, the cover member is formed so as to be mountable/demountable to/from the housing, and an insect trapping sheet that is formed of a base material sheet with an adhesive applied on one surface thereof is provided. Further, the insect trapping sheet is disposed on an inner surface of the cover member so as to be opposed to the filter.

Furthermore, in the present invention, preferably, in the air blowing device configured as above, the insect trapping sheet is formed in a dark color.

Furthermore, in the present invention, preferably, in the air blowing device configured as above, an attraction light source is provided that emits light for attracting insects to the insect trapping space, and the insect trapping sheet is arranged to extend between an upper portion and a lower portion of the insect trapping space. Further, the inflow port is disposed to face the lower portion of the insect trapping space, and the attraction light source is disposed to face the upper portion of the insect trapping space.

Furthermore, in the present invention, preferably, in the air blowing device configured as above, an impeller that is mounted to a rotary shaft of a motor of the air blower is arranged to face the inflow port, and the insect trapping sheet is projected in an axial direction of the motor so as to cover the motor in its entirety.

Furthermore, in the present invention, preferably, in the air blowing device configured as above, when an opening area of the suction port is indicated as A m3and an air volume of the air blower is indicated as Q m3/s, Q/A>0.7 is satisfied.

Furthermore, the present invention is characterized as follows. That is, an insect trapping method is such that there are provided a housing that has openings as an air inflow port and an air blow-off port, an air blower that is arranged in the housing, a filter that is arranged at the inflow port and collects dust in air, and a cover member that has an opening as an air suction port, is mounted to the housing, and forms an insect trapping space between the suction port and the inflow port, and the air blower is driven to trap insects that have entered the insect trapping space via the suction port. In the insect trapping method, an outer surface of the cover member is formed in a dark color.

Advantageous Effects of the Invention

According to the air blowing device of the present invention, the cover member has an opening as the suction port, is mounted to the housing, and forms the insect trapping space between the suction port and the inflow port of the housing, and the outer surface of the cover member is formed in a dark color. By this configuration, an adverse effect on a user's eyes is reduced, and insects can be easily attracted to the insect trapping space. Thus, insect trapping performance of the air blowing device can be safely improved.

Furthermore, according to the insect trapping method of the present invention, the cover member has an opening as the suction port, is mounted to the housing, and forms the insect trapping space between the suction port and the inflow port of the housing, and the outer surface of the cover member is formed in a dark color. By this configuration, an adverse effect on a user's eyes is reduced, and insects can be easily attracted to the insect trapping space. Thus, an insect trapping effect can be easily improved.

DESCRIPTION OF EMBODIMENTS

First Embodiment

With reference to the appended drawings, the following describes an embodiment of the present invention.FIG. 1shows a perspective view of an air blowing device of a first embodiment, andFIG. 2shows a side sectional view thereof. InFIG. 1andFIG. 2, each hollow arrow indicates an airflow. An air blowing device1is installed on a floor surface or the like in a room and has a housing2whose horizontal sectional shape is substantially elliptical. A demountable cover member3is mounted on a back surface side of the housing2, and an insect trapping sheet51, which will be detailed later, is arranged on an inner surface of the cover member3. A front surface of the housing2, a back surface of the housing2, and an outer surface of the cover member3are formed in black.

A sleeve portion12made of a transparent resin is provided in a circumferential edge portion of an upper surface of the housing2. An operation portion6is provided in a front portion of the upper surface of the housing2. The operation portion6has a plurality of buttons (not shown) and is operated by a user to perform operation setting for the air blowing device1. By operating the buttons, it is possible to issue instructions about driving on/off of the air blowing device1, changing of an air volume of an after-mentioned air blower10, on/off of an after-mentioned ion generator11, and so on.

An inflow port20is open through the back surface of the housing2, and a blow-off port5is open through the upper surface of the housing2. A protruding plate13that protrudes upward is provided in a center portion of the blow-off port5. The cover member3has a plurality of suction ports4formed therethrough, and an insect trapping space25that allows the suction ports4and the inflow port20to communicate with each other is formed between the cover member3and the back surface of the housing2.

In the housing2, an air blowing passage7is provided that links the inflow port20to the blow-off port5. In the air blowing passage7, in order from the inflow port20toward the blow-off port5(from upstream toward downstream of an airflow), a pre-filter8, a HEPA filter9, the air blower10, and the ion generator11are provided.

The air blower10is formed of a centrifugal fan arranged in a lower portion of the housing2and having a motor10aand an impeller10bmounted to a rotary shaft of the motor10a. The impeller10bis arranged to face the inflow port20. The air blower10sucks in air in an axial direction and exhausts the air in a circumferential direction. With the air blower10disposed in the lower portion of the housing2, without the need to increase a length of the housing2in an up-down direction, a flow passage area of an airflow discharged from the air blower10can be gradually increased. By operating the operation portion6, the air blower10is made to vary among a plurality of air blowing levels, which are “Very Low”, “Low”, “Medium”, and “High”. The air blower10increases in rotational speed in the order of “Very Low”, “Low”, “Medium”, and “High”. The air blower10may also be formed of an axial flow fan.

The pre-filter8is formed by welding a polypropylene mesh8bto a rectangular frame8athat is made of a synthetic resin such as ABS and has a plurality of columns and rows of windows. The mesh8bis formed to have such a mesh size that an insect such as a mosquito or a fly cannot pass therethrough. Large-sized particles of dust in the air can be collected by the pre-filter8.

The HEPA filter9is formed by welding a frame member9bto a filter medium9aso as to cover the filter medium9aby a hot melt process. Fine particles of dust in the air including a microparticulate substance, such as PM 2.5, can be collected by the HEPA filter9.

A deodorization filter having an absorbent material such as activated carbon may be disposed between the pre-filter8and the HEPA filter9. With this configuration, odor components in the air are absorbed, so that the air can be deodorized.

The ion generator11has an electrode (not shown) that generates ions upon application of a high voltage thereto, and the electrode faces an interior of the air blowing passage7. A voltage having an alternating waveform or an impulse waveform applied to the electrode. In a case where a positive voltage applied to the electrode, the electrode mainly generates positive ions H+(H2O)m, and in a case where a negative voltage is applied to the electrode, the electrode mainly generates negative ions O2−(H2O)n. Here, m and n are integers H+(H2O)m and O2−(H2)n aggregate on surfaces of airborne bacteria or odor components in the air and surround the airborne bacteria or the odor components.

Then, as shown in formulae (1) to (3), on surfaces of microorganisms or the like, an aggregate of [.OH](hydroxyl radical) and H2O2(hydrogen peroxide) that are active species is produced by collision, which destroys the airborne bacteria and so on. Here, m′ and n′ are integers. Accordingly, bacteria eradication and odor removal in a room can be performed by generating positive ions and negative ions and discharging them through the blow-off port5.
H+(H2O)m+O2−(H2O)n→.OH+½O2+(m+n)H2O  (1)
H+(H2O)m+H+(H2O)m′+O2−(H2O)n+O2−(H2O)n′→2.OH+O2+(m+m′+n+n′)H2O  (2)
H+(H2O)m+H+(H2O)m′+O2−(H2O)n+O2−(H2O)n′→H2O2+O2+(m+m′+n+n′)H2O  (3)

FIG. 3shows a back sectional view of an upper portion of the housing2of the air blowing device1. In an upper portion of the back surface of the housing2, a protruding portion28is provided that protrudes outward (to a cover member3side) with respect to the inflow port20. The protruding portion28is formed to extend in a left-right direction, and a concave portion28ais formed by concaving a middle portion of a lower surface of the protruding portion28in the left-right direction.

An attraction light source21is arranged at each of left and right end portions in the concave portion28aso that a light emission surface (not shown) thereof faces diagonally downward. Thus, the attraction light source21is disposed above the suction ports4of the cover member3so as to face an upper portion of the insect trapping space25. The attraction light source21has an ultraviolet light emitting diode (not shown) that emits ultraviolet light of about 365 nm, which attracts insects such as a mosquito.

In a middle portion of the concur portion28ain the left-right direction, a plate-shaped reflection portion61having a reflection surface61aformed on each of both surfaces thereof is provided in a hanging manner. The reflection surface61ais grained, and light P1 emitted from the light emission surface of the attraction light source21is diffused and reflected on the reflection surface61a. Light P2 diffused and reflected on the reflection surface61atravels toward the suction ports4. This can prevent a user from directly seeing the attraction light source21. The attraction light source21and the reflection portion61may be provided, instead of in the housing2, on the inner surface of the cover member3, or in the housing2and the cover member3.

FIG. 4shows a perspective view of the cover member3as seen from an inner side (a housing2side). The cover member3has an engagement piece (not shown) that is engaged with an engagement hole (not shown) provided through the housing2. Thus, the cover member3is demountably mounted with respect to the housing2. The cover member3is bent so as to be convex rearward, and a plurality of (in this embodiment, five) suction ports4are juxtaposed vertically in each of both left and right end portions of the cover member3. Instead, a single suction port4may also be provided.

FIG. 5shows a side view of the insect trapping sheet51. A plurality of insect trapping sheets51each formed of a base material sheet52with an adhesive53applied on one surface thereof are stacked via a release agent (not shown) such as silicone, and a laminate thus obtained is bonded onto a mounting plate55. The insect trapping sheets51and the mounting plate55are formed in black. The base material sheet52is formed of, for example, a sheet of paper, a resin film, or the like. The adhesive53is not particularly limited and, for example, an acrylic-based adhesive or the like can be used as the adhesive53.

FIG. 6shows a side view of the insect trapping sheets51in a state where one of the insect trapping sheets51is peeled off. The insect trapping sheets51are stacked via the release agent, and thus a used one of the insect trapping sheets51, to which insects have adhered to the adhesive53, is peeled off. Thus, an unused one of the insect trapping sheets51is exposed.

The adhesive53of each of the insect trapping sheets51may be water-soluble. Examples of materials of a water-soluble adhesive include dextrin, polyvinyl alcohol, polyvinyl pyrrolidone, starch, and gum arabic. With this configuration, the cover member3is demounted from the housing2, and a surface of the adhesive53to which insects, dust, and so on have adhered can be washed off with water or the like. Accordingly, a frequency of replacing the insect trapping sheet51can be decreased.

As shown inFIG. 4, engagement holes55aare provided at four corners of the mounting plate55, respectively. In an upper portion of the inner surface of the cover member3, a pair of left and right hook-shaped engagement pieces (not shown) that protrude toward the housing2are provided. In a lower portion of the inner surface of the cover member3, a pair of left and right support portions55bare provided, each of which is L-shaped in front view and has a groove (not shown) for inserting the mounting plate55thereinto.

Corresponding ones of the engagement holes55aof the mounting plate55are engaged with the engagement pieces of the cover member3, respectively, and left and right end portions of a lower end portion of the mounting plate55are placed in the support portions55b, respectively, so that the insect trapping sheets51are removably arranged on the inner surface of the cover member3, extending between the upper portion and the lower portion of the insect trapping space25. At this time, the insect trapping sheets51are opposed to the pre-filter8. Furthermore, the engagement holes55aare provided on upper and lower sides, and thus the insect trapping sheets51can be mounted so as to be able to be inverted in an up-down direction. This allows an entire surface of each of the insect trapping sheets51to be used effectively. Accordingly, a frequency of replacing the insect trapping sheet51can be decreased, and thus convenience can be improved.

FIG. 7shows a back view for explaining a positional relationship between the air blower10and the insect trapping sheet51. The insect trapping sheet51is disposed on the inner surface of the cover member3so as to be opposed to the lower portion of the housing2, and is projected in an axial direction (a direction orthogonal to a paper plane) of the motor10aof the air blower10so as to cover the motor10in its entirety. The insect trapping sheet51may also be projected in the axial direction of the motor10aso as to cover the motor10aand the inflow port20(the impeller10b) in their entirety.

Furthermore, as shown inFIG. 4, an odor generation portion70that generates an insect-attracting odor substance is provided on the inner surface of the cover member3. The odor substance is not particularly limited, and examples thereof include lactic acid. Lactic acid can easily attract insects such as a mosquito to the insect trapping space25. An installation location of the odor generation portion70is not limited to the inner surface of the cover member3, and as long as the installation location is within the insect trapping space25, the odor generation portion70may be provided on the back surface of the housing2.

A configuration may also be adopted in which the base material sheet52of each of the insect trapping sheets51contains an odor substance, thus forming an odor generation portion. Furthermore, a configuration may also be adopted in which the adhesive53and an odor substance are applied adjacently to each other in a staggered pattern or a striped pattern on the base material sheet52, thus forming an odor generation portion. Furthermore, a configuration may also be adopted in which the adhesive53of each of the insect trapping sheets51contains an odor substance, thus forming an odor generation portion. That is, an odor generation portion may be formed by providing an odor substance in each of the insect trapping sheets51. Furthermore, an odor generation portion may be formed by applying an odor substance on the mounting plate55.

In the air blowing device1configured as above, when the operation portion6is operated to instruct an operation of the air blowing device1, the air blower10is driven, and the attraction light source21is lit. The driving of the air bower10causes air in a room to flow into the insect trapping space25via the suction ports4. By the reflection surface61aemission light from the attraction light source21is diffused and reflected toward the suction ports4. Thus, insects can be attracted to the insect trapping space25via the suction ports4. Furthermore, this prevents a user from directly seeing the attraction light source21and thus can reduce an influence of ultraviolet light of the attraction light source21on the user's health.

Insects such as a mosquito are known to be fond of a black color. In this embodiment, the outer surface of the cover member3is formed in black, and thus an insect found in a region in a room, which is hardly reached by emission light from the attraction light source21, can be easily attracted to a vicinity of the cover member3. Furthermore, the back surface of the housing2(a region facing the insect trapping space25) is formed in black, and thus the insect attracted to the vicinity of the cover member3can be easily attracted to the insect trapping space25via the suction ports4. Furthermore, the insect trapping sheet51is termed in black, and thus the insect that has entered the insect trapping space25is easily attracted to and trapped by the insect trapping sheet51.

At this time, the insect trapping sheet51is disposed on the inner surface of the cover member3so as to be opposed to the pre-filter8. Thus, when an insect that has entered through the suction ports4is carried by a sucked-in airflow toward the inflow port20, the insect is trapped by the insect trapping sheet51opposed to the inflow port20. Thus, clogging of the pre-filter8with insects can be reduced. Furthermore, adherence of dust in the sucked-in airflow to the insect trapping sheet5can be reduced.

Furthermore, the insect trapping sheet51is arranged to extend between the upper portion and the lower portion of the insect trapping space25, the inflow port20is disposed to face the lower portion of the insect trapping space25, and the attraction light source21is disposed to face the upper portion of the insect trapping space25. This makes it easier for an insect being attracted to the attraction light source21to enter the insect trapping space25through upper ones of the suction ports4. An insect carried by a sucked-in airflow toward the inflow port20facing the lower portion of the insect trapping space25is likely to be trapped at a lower portion of the insect trapping sheet51. With this in view, a quantity of insects trapped at an upper portion of the insect trapping sheet51is increased by operating the attraction light source21, and thus insects can be uniformly trapped over the entire insect trapping sheet51. Accordingly, a frequency of replacing the insect trapping sheet51is reduced, and thus convenience can be improved.

Furthermore, the insect trapping sheet51is projected in the axial direction of the motor10aso as to cover the motor10ain its entirety. Thus, an airflow sucked into the inflow port20by the air blower10can be made to circulate in a wide range along the insect trapping sheet51. This makes it likely that an insect carried by the sucked-in airflow comes in contact with the insect trapping sheet51, and thus a quantity of insects trapped by the insect trapping sheet51can be increased.

Air that has flowed into the insect trapping space25flows through the inflow port20of the housing2into the air blowing passage7. At this time, large-sized particles of dust in the air are collected by the pre-filter8. Furthermore, fine particles of dust in the air including PM 2.5 or the like are collected by the HEPA filter9. Air flowing through the air blowing passage7on an exhaust side of the air blower10contains ions generated by the ion generator11. The ion-containing air from which dust has been collected is discharged through the blow-off port5. Thus, air in a room can be purified.

When the air blowing device1is in use, insects adhere to the adhesive53of an exposed one of the insect trapping sheets51. In this case, when a user demounts the cover member3from the housing2and peels off the used one of the insect trapping sheets51, to which the insects have adhered, an unused one of the insect trapping sheets51is exposed. This saves the trouble of replacing the insect trapping sheet51and thus can improve convenience of the air blowing device1.

Tables 1 to 3 show results of trapping rates of the air blowing device1with respect toCulex pipiens pallens, Culex pipiens molestus, andAedes albopictus, respectively.FIG. 8shows a plan view of a test room R1 for explaining an experiment for examining a trapping rate of the air blowing device1.

In the test room R1 (corresponding to a six-mat room) that was 3.5 m in length in a width direction, 2.9 m in length in a depth direction, and 2.2 m in length in a height direction, the air blowing device1was disposed at a position 0.3 m away from a left side wall WL. In the air blowing device1, the front surface of the housing2, the back surface of the housing2, and the outer surface of the cover member3were formed in black. As a hiding place for test insects, a rest box100formed of a black corrugated cardboard carton was used. In the rest box100, there were provided an equal number of opening portions (not shown) to the number of the suction ports4in the air blowing device1, each of which has an opening area substantially equal to that of each of the suction ports4. The rest box100was disposed at a position 0.3 m away from a right side wall WR. In the rest box100, no insect trapping sheets51are provided.

A cup75was disposed in a vicinity of each of diagonally positioned corner portions CR1 and CR2 in the test room R1. A piece of absorbent cotton impregnated with a bait for mosquitoes (a sugar solution having a sugar content of 3%) was put in the cup75. Furthermore, in a center portion in the test room R1, a cage80containing test insects was disposed. As the test insects, female images ofCulex pipiens pallens, Culex pipiens molestus, andAedes albopictuswere used.

The experiment was started by opening the cage80to release the test insects into the test room R1. At this time, the attraction light source21of the air blowing device1was lit, and the air blower10was driven at an air blowing level “Medium”. After a lapse of 22 hours (an experiment time) following the release of the test insects, the air blower10and the attraction light source21of the air blowing device1were stopped from operating, and the number of insects trapped by the insect trapping sheet51of the air blowing device1, the number of insects trapped in any other section than on the insect trapping sheet51in the air blowing device1, the number of insects in the test room R1 outside the air blowing device1, and the number of dead insects were counted. This experiment was implemented three times with respect to each of these types of test insects.

The test room R1 was kept well illuminated for 14 hours out of the experiment time and kept dark for remaining eight hours. Furthermore, a floor surface in the test room R1 was maintained at a temperature not lower than 25° C.

A trapping rate T (%) was calculated using Expression (1), where the number of insects trapped (the number of insects contained, in the air blowing device1) was indicated as Nc, and the number of insects collected from the entire test room R1 was indicated as Nr. The numbers of insects Nc and Nr also include the number of dead insects. Furthermore, based on a total of the numbers of insects as the of the experiment performed three times, the trapping rate T was calculated. The number of test insects released into the test room R1 is assumed to be the number of test insects.
T=100×Nc/Nr(1)

In the experiment with respect toCulex pipiens pallensshown in Table 1, with respect to 625 test insects, the number of insects collected was 618 and a collection rate (100×the number of insects collected/the number of test insects) was 98.9%. The number of insects (the number of insects trapped) in the entire air blowing device1was 588, a breakdown of which was 559 found on the insect trapping sheet51and29(inclusive of 25 dead ones) found in a section other than on the insect trapping sheet51. The number of insects found outside the air blowing device1, inclusive of the number of insects in the rest box100, was 30 (inclusive of 23 dead ones). A trapping rate of the entire air blowing device1was 95.1%, and a trapping rate of the insect trapping sheet51was 90.5%. These results indicate that the air blowing device1has extremely high insect trapping performance with respect toCulex pipiens pallens.

In the experiment with respect toCulex pipiens molestusshown in Table 2, with respect to 627 test insects, the number of insects collected was 625 and a collection rate was 99.7%. The number of insects (the number of insects trapped) in the entire air blowing device1was 615, a breakdown of which was 519 found on the insect trapping sheet51and 96 (inclusive of 54 dead ones) found in a section other than on the insect trapping sheet51. The number of insects found outside the air blowing device1, inclusive of the number of insects in the rest box100, was 10 (inclusive of 2 dead ones). A trapping rate of the entire air blowing device1was 98.4%, and a trapping rate of the insect trapping sheet51was 83.0%. These results indicate that the air blowing device1has extremely high insect trapping performance with respect toCulex pipiens molestus.

In the experiment with respect toAedes albopictusas shown in Table 3, respect to 640 test insects, the number of insects collected was 624 and a collection rate was 97.5%. The number of insects (the number of injects trapped) in the entire air blowing device1was 553, a breakdown of which was 534 found on the insect trapping sheet51and19(inclusive of 12 dead ones) found in a section other than on the insect trapping sheet51. The number of insects found outside the air blowing device1, inclusive of the number of insects in the rest box100, was 71 (inclusive of 21 dead ones). A trapping rate of the entire air blowing device1was 88.6%, and a trapping rate of the insect trapping sheet51was 85.6%. These results indicate that the air blowing device1has extremely high insect trapping performance with respect toAedes albopictus. After the experiment, 34 out of 71 found outside the air blowing device1flew toward an observer, which indicated thatAedes albopictusused in this experiment had high eagerness for blood sucking.

Table 4 shows results of an experiment of comparing an insect trapping effect between cases where the front surface of the housing2and the outer surface of the cover member3vary in color. In a test device A, similarly to the air blowing device1of this embodiment, the front surface of the housing2and the outer surfaces of the cover member3were formed in black. In a test device B, the front surface of the housing2was formed in black, and the outer surface of the cover member3was formed in white. In a test device C, the front surface of the housing2was formed in white, and the outer surface of the cover member3was formed in black. In a test device D, the front surface of the housing2and the outer surface of the cover member3were formed in white. Other components of the test devices A to D are configured similarly to those of the air blowing device1.

The experiment was performed in a following manner. That is, test insects (Culex pipiens pallens) were released at a position 1 m away from the test devices A to D and left alone for two hours in a state where the air blower10and the attraction light source21were stopped from being driven. Results are indicated as “Good” in a case where an observer judged that the number of insects adhering to the insect trapping sheet51was high and thus an insect trapping effect obtained was high and as “Poor” in a case where the observer judged that the number of insects adhering to the insect trapping sheet51was low and thus an insect trapping effect obtained was low. Furthermore, the results are indicated as “Fair” in a case where the observer judged that an insect trapping effect obtained was at a level between “Good” and “Poor”.

According to Table 4, the test device D exhibited a low insect trapping effect. On the other hand, the test device A exhibited a high insect trapping effect. Furthermore, the test device C also exhibited a high insect trapping effect. The test device B exhibited an insect trapping effect higher than that of the test device D and lower than those of the test device A and the test device C. These results revealed that an insect trapping effect of the air blowing device1can be improved by forming the outer surface of the cover member3in black.

Table 5 shows results of an experiment of comparing an insect trapping effect with respect toAedes aegyptibetween cases where the housing2and the outer surface of the cover member3of the air blowing device1vary in color.Aedes aegyptiis known as mosquitoes of a type that transmits viral infections diseases such as yellow fever and dengue fever. This experiment used a test device E in which, similarly to the air blowing device1of this embodiment, the front surface of the housing2, the back surface of the housing2, and the outer surface of the cover member3were formed in black. Furthermore, there was also used a test device F in which the front surface and the back surface of the housing2were formed in white. Furthermore, in the test device F, only a portion of the outer surface of the cover member3in a vicinity of the suction ports4was formed in black, and a remaining portion of the outer surface of the cover member3other than the vicinity of the suction ports4was formed in white. Other components of the test device F are configured similarly to those in the test device E.

FIG. 9is a view showing a layout in a test room R2 in which this experiment was implemented. In the test room R2 that was 3.3 m in length in a width direction, 2.6 m in length in a depth direction, and 3.0 m in length in a height direction, a partition90was disposed in a middle portion thereof in the width direction. The test device E was disposed on a left side with respect to the partition90, and the test device F was disposed on a right side with respect to the partition90. The test devices E and F were 0.55 m away from a left side wall WL and a right side wall WR, respectively, and 0.3 m away from a back side wall WB. Furthermore, a distance between the test device E and the test device F was set to 1.49 m.

In each of the test devices E and F, an appropriate amount of adhesive was applied to the pre-filter8by using a spray adhesive. Furthermore, the insect trapping sheet51was arranged also on a bottom surface in the insect trapping space25.

In a vicinity of each of the left side wall WL and the right side wall WR in the test room R2, a cup75was disposed 1.1 m away from a front side wall WF. A piece of absorbent cotton impregnated with a bait for mosquitoes (sugar, vitamin B1: a 10% sugar solution having a vitamin B1 content of 1%) was put in the cup75. Furthermore, in a center portion in the test room R2, a cage80containing test insects was disposed. As the test insects, female imagoesAedes aegyptiwere used.

The experiment was started by opening the cage80to release the test insects into the test room R2. After a lapse of 24 hours (an experiment time) following the release of the test insects, the number of insects trapped by the pre-filter8of each of the test devices E and F, the number of insects trapped by the insect trapping sheet51on the cover member3, the number of insects trapped by a bottom portion in the insect trapping space25, the number of insects in any other section than in each of the test devices E and F in the test room R2, and the number of dead insects were counted. A trapping rate (%) was calculated in a similar manner to that in cases of Tables 1 to 3.

During the experiment time, the attraction light source21of each of the test devices E and F was lit, and the air blower10was driven at the air blowing level “Medium.” Furthermore, a floor surface in the test device R2 was maintained at a temperature not lower than 26° C. After a lapse of the experiment time, the air blower10and the attraction light source21were stopped from operating.

With respect to 246 test insects, the number of insect collected was 246, and a collection rate was 100%. The number of insects trapped by the pre-filter8, the number of insects trapped by the insect trapping sheet51on the cover member3, and the number of insects trapped by the bottom portion in the insect trapping space25(the numbers of insects trapped) in the test device E were 119, 32, and 27, respectively, while in the test device F, these numbers were 38, 12, and 13, respectively. The number of insects trapped in the entire test device E (the number of insects trapped) was 178, and a trapping rate was 72.4%. On the other hand, the number of insects trapped in the entire test device F was 63, and a trapping rate was 25.6%. In each of the test devices E and F, the number of insects in any other section than in the each of the test devices E and F in the test room R2 was 5, and the number of dead insects was 0.

These results indicate that in a case where the front surface of the housing2, the back surface of the housing2, and the outer surface of the cover member3of the air blowing device1are formed in black, the air blowing device1has high insect trapping performance also with respect toAedes aegypti.

In this experiment with respect toAedes aegypti, unlike the experiment results shown in Tables 1 to 3, the number of insects on the insect trapping sheet51on the cover member3of each of the test devices E and F (the number of insects trapped) was smaller than the number of insects in any other section than on the insect trapping sheet51in the each of the test devices E and F. Presumably, this is because, in this experiment, the spray adhesive was applied to the pre-filter8, and the insect trapping sheet51was arranged in the bottom portion in the insect trapping space25, so that the number of insects trapped by the pre-filter8and the number of insects trapped by the bottom portion in the insect trapping space25were increased.

Next,FIG. 10is a view showing results of examining a relationship between an air velocity at the suction ports4and the number of insects trapped by the insect trapping sheet51(the number of insects trapped). A vertical axis represents the number of insects trapped, and a horizontal axis represents an average air velocity (unit: m/s) at the suction ports4. In experiments performed, test insects (Culex pipiens pallens) were released at a position 1 m away from the air blowing device1, and the air blowing device1was driven for 16 hours, with the air blower10made to vary in rotational speed. In each of the experiments, 100 test insects were used. After that, the number of insects trapped by the insect trapping sheet51(the number of insects trapped) was counted. An average air velocity V (m/s) at the suction ports4was calculated using Expression (2), where an opening area of the suction ports4was indicated as A (m2), and an air volume of the air blower10was indicated as Q (m3/s). Here, the opening area A of the suction ports4was set to be constant at 0.0297 m2(0.00297 m2×10 ports), which is a size of the opening area of the suction ports4formed in this embodiment, and the average air velocity V was made to vary by changing the air volume Q.
V=Q/A(2)

According toFIG. 10, when the average air velocity at the suction ports4was lower than 0.7 m/s, the number of insects trapped was not more than 31. Furthermore, when the average air velocity V at the suction ports4exceeded 0.7 m/s (Q/A>0.7), insects escaping out of the insect trapping space25were decreased, and the number of insects trapped was increased to not less than 57. Thus, by satisfying Q/A>0.7, insect trapping performance can be improved.

According to this embodiment, the outer surface of the cover member3forming the insect trapping space25between the suction ports4and the inflow port20is formed in black. Thus, insects can be easily attracted to a vicinity of the cover member3, and the insects easily enter the insect trapping space25. Accordingly, insect trapping performance of the air blowing device can be safely improved.

Furthermore, a region of the housing2, which faces the insect trapping space25, is formed in black, and thus insects in a vicinity of the suction ports4of the cover member3are easily attracted to the insect trapping space25via the suction ports4.

Furthermore, the insect trapping sheet51is disposed on the inner surface of the cover member3so as to be opposed to the pre-filter8. Thus, when an insect that has entered through the suction ports4is carried by a sucked-in airflow toward the inflow port20, the insect is trapped by the insect trapping sheet51opposed to the inflow port20. Thus, clogging of the pre-filter8with insects can be reduced.

Furthermore, the insect trapping sheet51is formed in black, and thus insects in the insect trapping space25can be easily attracted to the insect trapping sheet51. Accordingly, insect trapping performance of the air blowing device1can be further improved.

Furthermore, the insect trapping sheet51is arranged to extend between the upper portion and the lower portion of the insect trapping space25, the inflow port20is disposed to face the lower portion of the insect trapping space25, and the attraction light source21is disposed to face the upper portion of the insect trapping space25. This makes it easier for an insect being attracted to the attraction light source21to enter the insect trapping space25through upper ones of the suction ports4. An insect carried by a sucked-in airflow toward the inflow port20facing the lower portion of the insect trapping space25is likely to be trapped at a lower portion of the insect trapping sheet51. With this in view, a quantity of insects trapped at an upper portion of the insect trapping sheet51is increased by operating the attraction light source21, and thus insects can be uniformly trapped over the entire insect trapping sheet51. Accordingly, a frequency of replacing the insect trapping sheet51is reduced, and thus convenience can be improved.

Furthermore, the insect trapping sheet51is projected in the axial direction of the motor10aso as to cover the motor10ain its entirety. Thus, an airflow sucked into the inflow port20by the air blower10can be made to circulate in a wide range along the insect trapping sheet51. This makes it likely that an insect carried by a sucked-in airflow comes in contact with the insect trapping sheet51, thus a quantity of insects trapped by the insect trapping sheet51can be increased.

Furthermore, when Q/A>0.7 is satisfied, insects escaping out of the insect trapping space25are decreased, and thus the number of insects trapped by the insect trapping sheet51can be increased. Accordingly, insect trapping performance of the air blowing device1can be further improved. At this time, when Q/A is set to have a value in a vicinity of 0.7, while improving insect trapping performance, an increase in noise level of the air blowing device1can be suppressed.

While in this embodiment, the front surface of the housing2, the back surface of the housing2, the outer surface of the cover member3, the insect trapping sheet51, and the mounting plate55are formed in black, these are only required to be in a dark color and thus may be formed in, for example, navy blue or dark brown. Also in such a case, insects can be easily attracted to the insect trapping space25and the insect trapping sheet51.

Furthermore, a configuration may also be adopted in which the outer surface of the cover member3is formed in a dark color, and the front surface of the housing2and other portions are formed in a color different from the color of the outer surface of the cover member3. For example, as shown in the previously mentioned test device C in Table 4, the front surface of the housing2may be formed in a bright color such as white. Furthermore, the front surface of the housing2may be formed in a dark color (for example, mazarine) having lightness higher than that of the color (for example, black) of the outer surface of the cover member3. In this case, insects can be attracted to the outer surface of the cover member3and the front surface of the housing2, and insects attracted to the front surface of the housing2are attracted to the outer surface of the cover member3, which has lightness lower than that of the front surface of the housing2. Accordingly, insect trapping performance of the air blowing device1can be further improved.

Furthermore, while in this embodiment, the cover member3is arranged behind the housing2, a configuration may also be adopted in which the inflow port20is disposed in the front surface of the housing2, and the cover member3is arranged in front of the housing2.

Furthermore, while in this embodiment, the plurality of insect trapping sheets51are stacked on the mounting plate55, instead, the mounting plate55with a single insect trapping sheet51arranged thereon may be mounted to the cover member3. In this case, the insect trapping sheet51after use, to which insects have adhered, is replaced together with the mounting plate55.

Furthermore, in this embodiment, the insect trapping sheet51may be omitted. In a state where the air blower10is driven, due to a suction force of the air blower10, an insect that has entered the insect trapping space25can hardly escape out of the insect trapping space25. Thus, even when the insect trapping sheet51is omitted, the air blowing device1can trap insects in the insect trapping space25.

Second Embodiment

Next, a description is given of a second, embodiment of the present invention. This embodiment is different from the first embodiment in that an insect killing sheet is provided in place of the insect trapping sheet51. Other portions are configured similarly to those in the first embodiment.

In place of the insect trapping sheet51, the insect killing sheet (not shown) is mounted to the mounting plate55. The insect killing sheet is formed of, for example, a base material sheet (not shown) with a volatile insecticide applied thereto. Thus, an insect killing component is diffused in air in the insect trapping space25(seeFIG. 2) and thus kills insects therein, so that the insects can be trapped and stored in the insect trapping space25. At this time, preferably, a demountable tray or the like is provided in the lower portion of the insect trapping space25so that insects that have been killed and fallen in the insect trapping space25can be collected and easily discarded.

Third Embodiment

Next, a description is given of a third embodiment of the present invention. This embodiment is different from the first embodiment in that a spray portion is provided in place of the insect trapping sheet51. Other portions are configured similarly to those in the first embodiment.

The spray portion (not shown) is provided in an upper portion on the inner side of the cover member3. The spray portion has a tank (not shown) filled with an insecticide and sprays the insecticide into the insect trapping space25(seeFIG. 2). Thus, insects in the insect trapping space25are killed, so that the insects can be trapped and stored in the insect trapping space25. The spray portion may spray the insecticide, for example, after a lapse of a predetermined time following a start of an operation of the air blowing device1. Also, the insecticide may be sprayed by operating the operation portion6. It is only required that the spray portion60be able to spray an insecticide into the insect trapping space25, and thus the spray portion60may also be provided in the housing2instead of in the cover member3.

Fourth Embodiment

Next, a description is given of a fourth embodiment of the present invention. This embodiment is different from the first embodiment in that an electric shock insect killing portion is provided in place of the insect trapping sheet51. Other portions are configured similarly to those in the first embodiment.

The electric shock insect killing portion (not shown) is provided on the inner surface of the cover member3. The electric shock insect killing portion generates a high voltage and kills an insect that has come in contact therewith by shocking it with the high voltage. Thus, without using a chemical agent such as an insecticide, insects that have entered the insect trapping space25can be trapped and stored in the insect trapping space25. The electric shock insect killing portion may be provided in the housing2instead of in the cover member3.

In the first embodiment to the fourth embodiment, the attraction light source21may be omitted from the air blowing device1. Furthermore, while the first embodiment to the fourth embodiment have been described by using, as an example, the air blowing device1provided with the HEPA filter9and the ion generator11, a configuration may also be adopted in which the HEPA filter9and the ion generator11are omitted, and a circulator that blows off air through the blow-off port5and thus circulates air in a room is used to trap insects.

INDUSTRIAL APPLICABILITY

The present invention is usable in an air blowing device that traps insects that have entered an insect trapping space between a housing and a cover member.

LIST OF REFERENCE SYMBOLS

21attraction light source

52base material sheet