This invention relates to a portable sprayer and is particularly concerned with a sprayer for treating an area with two different products in a single pass. The sprayer is particularly adapted for applying mosquito control products, although its use is not limited to this application.
The most effective treatment of an area for mosquito control results from the application of two products. The first product, known as a knockdown product or knockdown treatment, is designed to kill mosquitoes already in a treatment zone. It is most effective when applied as an ultra low volume (ULV) spray or fog with small, lightweight droplet sizes. The second product, known as a barrier product or barrier treatment, is designed to prevent mosquitoes from entering the treatment zone. It is best applied in larger, heavier droplet sizes that impinges on plants and foliage with a material that repels and/or kills mosquitoes. The difference in required droplet sizes for the knockdown product and barrier product dictates that two separate nozzles be used to distribute the two products. This has been done commercially with a variety of units, all having separate sprayers.
Some prior art ULV sprayers of this type are mounted on a truck and are engine-powered. Similarly, truck-mounted mist blowers having very large blasts of air are powered by gasoline engines. With these types of units mounted on trucks there is ample space to accommodate separate nozzles and ample power available to drive them. Such is not the case with sprayers intended for household or consumer use. Other prior art sprayers have ULV nozzles in a hand-held unit powered by a small gasoline engine or an electric motor using a power cord. There are also prior art barrier product sprayers that supply a liquid stream only. That is, there is no air mixed with the liquid. These are available for nursery and household use in both truck-mounted and hand-cart mounted units. They are powered both by gasoline engines and electric motors, including battery powered motors.
Household sprayers need to be portable, preferably hand-held units which do not require an electrical cord. Because of these limitations in portable units, the conventional practice in household sprayers has been to make two separate passes with two separate nozzles, one for applying the knockdown product and one for applying the barrier product. Obviously, this is not the most convenient arrangement since making two passes takes twice as long as making one pass. Also, with this conventional practice either two entirely separate sprayers must be used or a single sprayer must have its nozzle and product supply reservoir changed after the first pass. Neither of these arrangements is optimal.
Furthermore, it is desirable to use battery power for household sprayers because rechargeable batteries are more convenient to use compared to units powered by gasoline engines or household current, the latter requiring a long, unwieldy extension cord. While hand-held, battery-powered sprayers are preferable from a convenience standpoint, the batteries are limited in the amount of power they can supply so the sprayer must be designed to minimize power use and make changing the battery pack simple and quick. It has not previously been feasible to have a dual-output sprayer including a ULV nozzle in a hand-held, battery-powered unit.
A primary object of the present invention is a portable sprayer having dual output nozzles for applying two separate products at the same time.
Another object of the invention is a sprayer of the type described in which the nozzles produce different droplet sizes.
Yet another object of the invention is a sprayer which is battery powered.
A further object of the invention is a sprayer having dual product chambers with quick connect fluid connectors between the chambers and the fluid lines supplying product to the pump.
Still another object of the invention is a sprayer of the type described which detects a low voltage condition in the batteries and prevents operation of the unit under such conditions.
These and other desired benefits of the invention, including combinations of features thereof, will become apparent from the following description. It will be understood, however, that a device could still appropriate the claimed invention without accomplishing each and every one of these desired benefits, including those gleaned from the following description. The appended claims, not these desired benefits, define the subject matter of the invention.
The portable sprayer of the present invention is shown generally at 10 in
Other externally-visible features of the sprayer include a handle 28 and a control switch 30 on the top of the handle. In front of the switch there are a pair of openings or windows 32, 34 through which operational indicators can be viewed. The indicators may be as simple as an LED which shows when the battery is charging. Or the indicators could include a more complicated readout showing the user the battery charge level, the amount of liquid left in the product chambers, or similar information.
The housing 12 is split vertically into two case-like halves.
The housing has a plurality of internal walls or partitions that define various compartments. Front and rear vertical partitions 60, 62 each have a cutout portion 64. The cutouts receive the wind tunnel 66 as will be explained. Beneath the wind tunnel and between the vertical partitions 60, 62 there is a pump compartment 68. A divider wall 70 extends from the rear vertical partition 62 to the rear wall 42. It defines a battery compartment 72 and a control circuit compartment 74. Top and bottom horizontal walls 76, 78 join the front vertical partition 60 and extend to the front of the housing to define the liquid reservoir compartment 80. The bottom wall 78 has an opening that receives a connector support beam 82 for a quick-connect fluid connector. The female mating half of the fluid connector (not shown) is mounted in the bottom of the reservoir cartridge. Just underneath the corner of the bottom wall 78 and front vertical partition 60 are passages (one of which is shown at 84) for the fluid supply lines.
Near the junction of the rear vertical partition 62 and the bottom wall 40 there is an indentation in the bottom wall that forms a charging receptacle 86. Electrical connectors are located here to electrically connect the battery pack to a charging electrode extending upwardly from the cradle 36. At the lower left corner of the charging receptacle the bottom wall has a catch 88. The catch is engageable with a latch on the battery pack to retain the battery pack in the battery compartment 72. In this regard it will be noted that the bottom wall 40 does not extend to meet with the rear wall 42. Instead, the battery pack 120 forms the bottom rear corner of the sprayer unit when it is installed. This construction allows a user to remove and replace the battery pack with just one hand, as will be explained more fully below.
The other housing half is similar. The housing halves may be fastened together with screws or the like. Each housing half will also include a plurality of mounting posts or pads which receive screws for attachment of the various components in their respective compartments.
Turning now to the components mounted in the housing, a description of the liquid reservoir cartridge will be given first. The liquid reservoir cartridge itself is partially visible at 90. The reservoir is a replaceable, twin-chamber cartridge or package. Preferably the cartridge has relatively stiff side walls, a top and a floor. Inside the cartridge are two chambers. Preferably each chamber comprises a plastic bag capable of retaining liquid therein. One of the bags will contain the chemistry for the knockdown product and the other bag will contain the chemistry for the barrier product. The floor of the reservoir cartridge has two quick-connect, female connector halves (not shown). There is one female connector for each bag and they are in fluid communication with the interior of each bag. The female connector halves mate with corresponding male quick-connect connectors 92A, 92B (
Inside the reservoir compartment 80 there is a tray 100 that mounts the reservoir cartridge 90. The tray has a floor 102, side walls 103 and a top wall 104. The floor is attached to a cam 106 that is pivoted to the housing walls. The cam is also connected to the front door 26. The door serves as a lever that actuates the cam 106. Opening the door through a clockwise motion (as seen in
The next major area of the housing is the pump compartment 68. It contains a low-energy air pump 108 which is driven by an air pump motor 110. A bracket 109 mounts the air pump 108 to the housing. The air pump 108 supplies pressurized air to the first nozzle through an air pipe 112. Behind the air pump is a low energy liquid pump 114 which is driven by a liquid pump motor. The liquid pump motor is hidden in
The battery compartment 72 contains a battery pack shown generally at 120. Further details of the battery pack are described below. Connectors in the battery pack electrically connect the battery pack to the control circuit 122 which is mounted in the control circuit compartment 74. The control circuit is mounted on a printed circuit board. The printed circuit board has a power supply section that includes connectors for wires that supply electric power to the air pump motor 110 and the liquid pump motor, as well as to the fan motor 158 in the second nozzle. The printed circuit board also connects to the switch 30 in the handle and to the indicator LED's in the handle. A microcontroller is included on the printed circuit board to provide a level of intelligence that, for example, prevents operation when the battery voltage drops to a level that is incapable of producing the proper droplet sizes, when the reservoir cartridge is empty or not installed, or when the sprayer is mounted in the charging cradle. Also, the microcontroller is programmed to turn the air supply motors on before the liquid pump is activated and turn the air supply motors off after the liquid pump is shut down. This assures that liquid never flows without an accompanying air supply and any residual liquid in the emitters is blown out the nozzles and will not remain in the unit after it is turned off.
The first nozzle for dispensing the knockdown product is shown generally at 124 in
The second nozzle for dispensing the barrier product is shown generally at 140 in
The battery pack 120 is illustrated in
The use and operation of the sprayer are as follows. With a fully charged battery pack and a full liquid reservoir cartridge, the user grasps the sprayer by the handle 28 and removes it from the cradle 36. The sprayer is transported to the area to be treated and, after assuring that conditions are safe for treating the area, the user acutates the control switch 30. This activates the microcontroller which first verifies that a non-empty liquid reservoir is present in the reservoir compartment 80 and that sufficient battery voltage is available to generate the required air and liquid flow rates and pressures. If so, the microcontroller activates the air pump motor 110 and the fan motor 158. Shortly thereafter the microcontroller activates the liquid pump which sends the knockdown liquid to the emitter 132 and the barrier liquid to the emitter 168. The user then traverses the perimeter of the area to be treated. If the microcontroller senses that the battery voltage has fallen below a level needed to assure proper droplet formation it will shut down the liquid pump and then the air motors. The user can then change the battery pack as described above to continue the treatment process. Similarly, if the microcontroller senses that the liquid reservoirs are empty, it will shut down the liquid pump and then the air motors. The user can then change the liquid reservoir cartridge as described above. When the entire area to be treated has been treated the user releases the control switch. The liquid pump shuts off, followed by the air motors. The user returns the sprayer and auxiliary battery pack to the charging cradle so the batteries will recharge and be ready for the next application.
While the preferred form of the invention has been shown and described herein, it should be realized that there may be many modifications, substitutions and alterations thereto. For example, instead of using a single liquid pump with dual heads, separate pumps could be provided, one for each product. Alternately, the pump could be replaced entirely by one or more aerosol pressure cans. If aerosol cans are used, they would be a replacement item just like the liquid reservoir cartridge. Also, while various components of the sprayer are referred to as being in the housing, it will be understood that this is meant in a general sense that the components are connected, attached or mounted on, in or to the housing. In other words, portions of the components may protrude outside of a boundary wall of the housing and still be considered in the housing. A further alternate construction may include a separate lever inside the door 26. Thus, instead of the door actuating the reservoir cam 106, a lever just inside the door would be connected to the cam to actuate it. Also, while a hand-held sprayer has been shown and described, other arrangements are possible that would still allow the sprayer to be portable. For example, the housing might have wheels incorporated therein or the housing could be mounted on a ground-engaging cart.