Abstract:
A novel method and apparatus for applying materials, such as poisons or other rodent control liquids, to the dorsal fur of rodents is disclosed. The apparatus is suspended over a suspected rodent scent trail, senses the presence of a rodent in a target region located along that trail, and responsive to such sensing dispenses material from a reservoir contained in the apparatus onto a dorsal fur region of the rodent. The control materials are subsequently ingested during habitual grooming behavior. The method and apparatus of the present invention is intended to overcome bait shyness, neophobia, and primary and conditioned taste aversions.

Description:
ispensing means. 
     As seen from the above, a primary object of the present invention is the provision of a dispensing device which applies measured amounts of a rodent control material to the dorsal fur of rodent pests. 
     A further aim of the present invention is the provision of a rodent control device which minimizes the neophobia exhibited by the target species. 
     A further object of the present invention is the provision of a rodent control device which minimizes the effects of primary and conditioned taste aversions. 
     These and other objects of the present invention will become apparent from the following more detailed description. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an isometric view of the preferred embodiment device of the present invention shown mounted over a rodent trail at a wall-floor interface; 
     FIG. 2 is a cross-section of the preferred embodiment device of FIG. 1, taken along a plane which is perpendicular to the wall illustrated in FIG. 1; 
     FIG. 3 is a cross-section of the preferred embodiment device of FIG. 1, taken along a plane which is perpendicular to the plane of FIG. 2; and 
     FIG. 4 is an alternate embodiment of the present invention, which is shown mounted on a tree limb. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     While specific examples have been selected for reference in connection with the following description, those of ordinary skill in the art will recognize that departures may be made from the materials and methods described hereinafter without departing from the scope of the present invention, which is defined more particularly in the appended claims. 
     The preferred embodiment apparatus of the present invention is designed to apply rodent control materials, such as poisons, to the dorsal fur region of rodents. 
     With reference to FIGS. 1-3, this preferred embodiment comprises a housing which is suspended over a suspected rodent trail. As illustrated in FIGS. 1-3, one common location for such a trail is at a wall-floor interface. Accordingly, the embodiment of FIGS. 1-3 is particularly adapted for installation over a trail located at that interface. The preferred housing designated generally 100 comprises a box 102 onto which a top 104 is fitted using flange 110. The housing is suspended over a suspected rodent trail 14 using a suspension means which comprises a bracket 152 which is attached to the wall using screws 156 and 158. The bracket 152 defines a track which is interlockingly engaged by track 154 which projects from a back surface of the box. Accordingly, the entire device may be installed simply by mounting bracket 152 at the appropriate height and laterally sliding track 154 into its installed position. 
     The preferred apparatus of the present invention further comprises a reservoir 200 for containing liquid rodent control materials, rodent sensing means disposed generally above trail 14 for detecting the presence of a rodent in a target region located along said trail; and material dispensing means responsive to said rodent sensing means for dispensing a predetermined amount of a said material from said reservoir onto a dorsal fur region of said rodent while said rodent is within said target area. 
     Reservoir 200 is also generally box shaped, and designed to slidingly engage interior surfaces of the housing, 100 so that it may be easily removed therefrom when the top 104 of the housing is not in place. The lower surfaces of the reservoir 200 define a first lower inclined surface 200a and a second lower inclined surface 200b which converge towards a spout which is fitted with a spout cap 200c. The inclined surfaces of the reservoir cooperate with an upper inclined boss 108 and lower inclined boss 106 which project inwardly from the housing to cooperate with the reservoir to align the spout and associated dispensing equipment so that they are properly aimed at a target region disposed along trail 14. 
     The rodent sensing means is disposed generally above the trail in a manner which causes minimal visual or olfactory interference with the scent trail. The preferred rodent sensing means comprises a plurality of sensors located along the trail for detecting the rodent position with respect to the target area. In the preferred embodiment, each of these sensors comprises an infrared light source, such as light sources 302, 310, 314 and 318, and infrared detector, such as detectors 304, 308 and 312 and 316. Each of the infrared light sources is aimed to bounce off a reflective surface such as mirrors 320, 322, 324 and 326 which cause the infrared light to bounce back to its respective detector unless interrupted by a rodent on the rodent trail. Although in alternate embodiment it may be permissible to locate the reflective surface directly on the suspected rodent trail, it is presently preferred to dispose the reflective surfaces generally adjacent to and above the trail, as for example on mirror standards 330, 332, 334 and 336. The use of such standards to locate reflective surfaces above but adjacent to trail 14 prevents the preferred device from substantially interfering with the scent trail on the floor, while at the same time facilitating prealignment of the sensing means prior to installation. 
     Although the above described sensors are presently preferred it is understood that suitable sensors also comprise heat sensors, ultrasonic motions sensors, vibrations sensors, or a combination of the above. Vibration sensors are believed particularly suitable when the apparatus is applied on a vibration sensitive surface such the tree limb illustrated in FIG. 4. 
     The rodent sensing means of the preferred embodiment device is designed to sense not only the presence of a rodent on the portion of the rodent trail located generally under the housing, but also to ascertain whether the rodent is located within a target region disposed under the rodent control material dispensing means. Accordingly, a conventional logic chip is provided for determining whether at least two of the sensors located on opposite sides of the target region are simultaneously interrupted, whereupon a timed release of the control substance by the dispensing mechanism will be effected for a predetermined length of time. In accordance with the preferred embodiment, the sensors may also detect the relative size of the animal located in the target region as measured by the number of sensors and/or the interruption which the animal causes for each of the sensors. For example, an animal which simultaneously interrupts all four of the sensors may be determined to be a larger animal, and therefore be subject to a larger dose of control material. 
     The material dispensing means of the present invention comprises an electrically actuated valve and a nozzle means for directed liquid control material towards the target region when the valve is in its open position. As shown in FIGS. 1-3, the electrically controlled valve 402 is preferably a valve which is in communication with the spout cap 200c of the reservoir which in turn communicates to a nozzle 404 which is aimed towards the target region. Since the reservoir 200 is vented to the atmosphere by vented cap 202, when valve 402, which may be a solenoid valve, is opened, a gravity spray of liquid control material 204 will be dispensed into the target region. The actual amount of material dispensed into the control region may be varied either by the amount of time the valve is left in its open position and/or the degree to which the valve is opened. In the preferred embodiment an internal power source (battery and/or transformer) 406 is provided for powering chip 306, sources 302, 310, 314 and 318, sensors 304, 308, 312 and 316 and solenoid valve 402. External power may also be employed. Although not shown in the drawings, one of ordinary skill in the art will recognize that the infrared light sources, detectors, chip, power source and solenoid valve should be appropriately connected by leads. In particular, the solenoid valve 402 should be connected to the remainder of the wiring with leads of sufficient length to allow the entire dispensing mechanism to be removed with the reservoir without disconnecting the electrical leads attached thereto. By mounting the entire dispensing means on the reservoir, as shown in FIG. 2, its easy removal for servicing and adjustment may be effected simply by removing top 104 and withdrawing the entire reservoir from the housing. 
     The present invention also comprises sound deadening means for the purpose of minimizing auditory conditioning of target animals exposed to the device. Accordingly, a baffle 114 defining a sound deadening chamber 116 is disposed above the floor of the box. Sound deadening materials such as insulation, may also be packed into the lower region of the box to further reduce the noise created during the operation of the device. Accordingly, it is anticipated that the noise level emitted by the device toward the rodent trail will not be sufficient to create a conditioned avoidance of the trail by the target rodent pests. 
     As seen in FIGS. 1-3 the height of box 102 is designed to permit target rodents to pass thereunder nearly free of obstruction. Since it is desired, however, to further exclude non-target species from the device, a fingered guard designated generally 500 is provided which further restricts access of nontarget species to the target region of the device. In combination with the above described sensing means of the present invention, this guard minimizes the likelihood that a nontarget species, such as a cat, might be unnecessarily exposed to control liquid 204. 
     It is also anticipated that the apparatus of the present invention may be installed over trails located in other positions. In FIG. 4, an alternate embodiment device designed for installation over a tree is illustrated. This device, designated generally 600, operates in the same manner as described for the embodiment of FIGS. 1-3. In this embodiment, however, elongated support members 606 and 608, which are attached to a lower surface of the tree limb, position the remainder of the apparatus at a predetermined distance above the tree limb surface. For the particular embodiment shown, the sensing means is a heat sensor or ultrasonic sensor which does not require the reflective surfaces shown in the embodiments of FIGS. 1-3. As before, the box shaped housing 604 is fitted with an easily removable top 602 which facilitates easy refill of the reservoir contained therein. Target animals, such as rodent 10 which travel along tree limbs, such as tree limb 12, will therefore receive the desired dosage of control material, whereas the orientation of member 606 and 608 help to exclude non-target species from the target region located under the remainder of the device. 
     As seen from the above, a simple inexpensive apparatus is provided which should be effective in controlling target rodent pests.