Abstract:
A mole or animal detector includes apparatus for placement over a portion of a soil surface overlaying a portion of a mole tunnel, including a detector or sensor and circuitry for detecting movement of the portion of the soil surface indicative of passage of a mole through the underlying tunnel portion and generating a signal representative thereof, the signal being directly observable or audible or otherwise sensible, or transmitted to a receiver operable for emitting a signal, for instance, at a remote location.

Description:
TECHNICAL FIELD  
       [0001]     This invention relates generally to apparatus for detecting the presence of a mole in a mole tunnel beneath the soil surface, and, more particularly, to a mole detector which externally detects or senses raising or lifting or other disturbance of surface soil over the tunnel representative of presence of the mole, and which detector emits a signal representative of such disturbance and thus the presence of the mole to allow and/or facilitate trapping or otherwise removing or eliminating the mole.  
       BACKGROUND ART  
       [0002]     Various devices are known for capturing and killing rodents and animals such as moles in subterranean environments including tunnels located just beneath the soil surface. Reference in this regard Kintz U.S. Pat. No. 4,187,634, Van Dijnsen et al. U.S. Pat. No. 5,040,326, Kim U.S. Pat. No. 5,953,853, and Farrell et al. U.S. Pat. No. 6,445,301.  
         [0003]     However, a shortcoming of the known devices is that they typically require some apparatus to be buried in, project into, or otherwise be present within a mole tunnel itself, which may require some hand digging. Also, moles may be less inclined to travel into areas of a tunnel that contain foreign objects or which have been extensively or unnaturally disturbed, altered or modified. Further, some of the known devices include spring loaded elements and/or poisons, that can present a danger to children and other persons, as well as pets.  
         [0004]     Therefore, what is sought is a mole detector which is less, if at all, invasive into a tunnel, is easy and convenient to use, and which presents no danger to persons that come into contact with it, yet which is effective for detecting the presence of moles and other animals in relatively shallow subterranean tunnels.  
       DISCLOSURE OF THE INVENTION  
       [0005]     According to the invention what is disclosed is a mole or animal detector including, apparatus for placement over a portion of a soil surface overlaying a portion of a mole tunnel, including a detector or sensor and circuitry for detecting movement of the portion of the soil surface indicative of passage of a mole through the underlying tunnel portion and generating a signal representative thereof. The signal can be directly observed or heard by a person to enable the person to take action with regard to the mole or other animal, such as killing the mole or animal in place in the tunnel, or removing it and killing or trapping it, or the signal can be transmitted or conveyed to a remote receiver signal device operable for emitting a visible, audible or otherwise sensible signal indicative of the presence of a mole or other animal in the tunnel. Preferably, the soil over the tunnel under the apparatus is first tamped down, such that the mole or animal will lift or raise the tamped soil, thereby actuating the detector. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]      FIG. 1  is a perspective representation of a soil surface including an elongate raised soil section representative of soil covering a mole tunnel, showing a portion of the soil covering the mole tunnel compacted to collapse an underlying portion of the tunnel, and a mole detector of the present invention positioned for placement over the compacted soil along with a receiver/signal device of the invention;  
         [0007]      FIG. 2  is a schematic representation of elements of the mole detector of  FIG. 1 ;  
         [0008]      FIG. 3  is a side view of the detector of  FIG. 1 ;  
         [0009]      FIG. 4  is an end view of the detector;  
         [0010]      FIG. 5  is a cross-sectional view taken along line  5 - 5  of  FIG. 4 ; and  
         [0011]      FIG. 6  is an alternative sectional view along line  5 - 5  of  FIG. 4 , showing an actuator of the detector in an alternative position. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0012]     Referring now to the drawings, in  FIG. 1 a  mole detector  10  constructed and operable according to the teachings of the present invention is shown. Mole detector  10  includes detector apparatus  12  and a separate receiver/signal device  14 . Detector apparatus  12  is shown in position for placement on a soil surface  16  exhibiting or including evidence of subterranean mole habitat, particularly well known elongate tunnels (not shown) located just below soil surface  16 . Evidence of such relatively shallow subterranean tunnels typically includes an elongate trace of raised, broken soil, such as denoted at  18 . Generally, traces such as trace  18  are formed as a small animal such as a mole or other rodent burrows through the soil just beneath the surface for foraging insects from plant roots lying just beneath the surface. It has been observed that after traces such as a trace  18  are formed, if holes or openings not made by the mole or other animal appear, they will be patched or filled by the animal to prevent exposure of the tunnel interior to the outside environment. It has been additionally observed that moles will often repair and reopen portions or sections of their tunnels that have been collapsed due to natural causes, and due to being stepped on by a human or animal foot or rolled over by a vehicle wheel. In contrast, it has been observed that some moles and other rodents will have a tendency to avoid foreign or unfamiliar objects placed in a previously dug tunnel such as the one represented by trace  18 , such that the effectiveness of traps and detectors that require placement of foreign elements in and/or in proximity to tunnels, or which require unnatural or unusual alternation of a tunnel, may be less effective as the mole may have a tendency to avoid those portions of the tunnels containing such elements or which have been so altered.  
         [0013]     Detector apparatus  12  constitutes an effort to avoid the requirement of placing a foreign element in or in close proximity to the interior of a mole tunnel, and unnatural or unusual alterations or modifications of a mole tunnel, by providing detection of disturbance of soil over the tunnel, such as represented by trace  18 , indicative of movement or other activity of a mole in or though the underlying tunnel. In this way, no foreign object or element is introduced into the tunnel itself. As an example, detection apparatus  12  is shown in position for placement over a portion  20  of trace  18  for detecting disturbance and/or movement of soil  22  within portion  20 . To facilitate detection, portion  20  of trace  18  is shown tamped or pressed down somewhat, which can be easily accomplished, for instance, using one&#39;s foot or hand, a shovel, or a piece of lumber, or the like, to partially reduce the sectional area of the underlying tunnel. This is with the intent that the mole or other rodent or animal will be required to lift or raise, or otherwise disturb overlaying soil  22 , which will be detected by detector apparatus  12  which will cause the outputting of a signal indicating the presence of the mole or other animal, as explained next.  
         [0014]     Referring also to  FIG. 2 , detector apparatus  12  is connected to a transmitter  24  and is operable for activating or sending an input signal to transmitter  24  or otherwise changing the state of transmitter  24  to cause transmitter  24  to emit an output signal as denoted at  26 , through the atmosphere or over a suitable conductive path, such as a wire, cable or the like, to be received by a receiver/signal device  28  of mole detector  10  which, in turn, outputs a visible, audible or other signal indicative of the soil disturbance movement, and thus, presumably the presence of a mole or other animal in or near the vicinity of portion  20  of trace  18 . An observer or recipient of the output signal from device  28  can then proceed to the location of portion  20  of trace  18  and take desired action, such as digging up and capturing or killing the mole or other animal.  
         [0015]     Referring also to  FIGS. 3, 4  and  5 , detector apparatus  12  is preferably supported in some simple manner in close proximity to a portion of a trace such as portion  20  of trace  18 , so as to be capable of detecting disturbance or movement of soil representative of the movement of, and thus presence of, a mole in the underlying tunnel. A preferred manner of accomplishing this houses elements of apparatus  12  in an elongate, concave shell  30 , preferably having a semi-cylindrical sectional shape ( FIG. 4 ) extending between parallel, spaced lower edge portions  32  and  34 , and opposite end portions  36  and  38 , defining an elongate, downwardly and longitudinally open space  40 . At about midway between end portions  36  and  38  of shell  30 , shell  30  includes an upwardly extending hollow detector housing  42  including an enclosed or covered upper end portion  44  and a downwardly facing open lower end portion  46 , defining an interior cavity  48  which is downwardly open and connects to space  40  of shell  30 . A preferred shell  30  can be easily made from a common commercially available plastic plumbing pipe tee for 4 or 6 inch diameter piping, the long pipe section of which can be cut, such that space  40  will have a horizontal extend of at least about 3 inches so as to be capable of spanning a typical tunnel, and preferably from about 4 to 6 inches or so, and a vertical extent of 2 to 3 inches such that only the actuator will be contacted when a tamped down portion of an underlying tunnel is raised or lifted by a mole or other animal. Upper end portion  44  of the tee can be enclosed by a standard commercially available removable pipe cap.  
         [0016]     Detector apparatus  12  includes an actuator  50  suspended from a support member  52  attached to detector housing  42  so as to be located at a desired position in space  40  such that when detector apparatus  12  is positioned over a portion of a trace, such as portion  20  of trace  18 , upward or other movement or disturbance of soil  22  will cause actuation of detector apparatus  12  for causing transmitter  24  to output signal  26 . Preferred actuator  50  has a bulbous or other suitable shape so as to be capable of resting on or being located in close proximity to soil  22  with only minimally or not at all disturbing the soil  20 , particularly so as not to extend or project into the soil, so as to be less likely to be perceived as a foreign object or element or an unnatural or unusual occurrence in an underlying tunnel and so as to not further disturb the overlaying soil. Actuator  50  is also preferably relatively lightweight, such that slight upward lifting or raising or other forces or movements or disturbances of soil  22  will be sufficient to also lift or raise or otherwise actuate actuator  50  for activating detector apparatus  12 , without significant risk of actuator  50  puncturing the soil and projecting into the underlying tunnel. Here, actuator  42  is suspended from support member  52  by an elongate shaft  54  including a threaded upper end  56  which passes through a generally vertical hole  57  in member  52 , the vertical position of shaft  54  and actuator  50  being determined by the position of a nut  58  threadedly engaged with end  56  to prevent downward movement of shaft  54  through hole  57 . This nut allows easily adjusting the position of actuator  50  in the space. An L-shape bracket  60  is supported on nut  58  and retained in position by a second nut  58 . A magnet  62  is attached to a downwardly extending leg of bracket  60  with double sided tape  64 , or other adhesives or fasteners, or in any other suitable manner in proximity to a magnetic switch  66  connected in circuit with transmitter  24 . The adjustability of the nut also allows adjusting the position of the magnet relative to the switch.  
         [0017]     Magnetic switch  66 , transmitter  24  and receiver/transmitter device  28  are preferably well known, commercially available devices purchasable together as a unit, for instance, from Desa International, Inc., of Bowling Green, Ky., U.S.A. In operation, movement of magnet  64  relative to magnetic switch  66  of transmitter  24  is operable to change the state of magnetic switch  66  to activate transmitter  24  for outputting signal  26 , which here is a radio signal through the atmosphere, for receipt by receiver/signal device  28 , which can be located some maximum distance from transmitter  24 , as determined by the range of the transmitter and sensitivity of the receiver selected, battery strength, atmospheric conditions, and the like. Transmitter  24  is preferably powered by a battery contained therein, but can also be alternatively powered by any suitable energy source, such as by connection to a source or household current, solar power or wind power. Likewise, receiver/signal device  28  can be powered by an internal or external battery, household power, such as by connection to an outlet such as outlet  68  ( FIG. 1 ) or it can be alternatively powered by a solar or wind source, or the like.  
         [0018]      FIG. 6  shows detector apparatus  12  with actuator  50  lifted by soil  22  (in phantom) showing resultant movement of magnet  62  relative to magnetic switch  66  of transmitter  24  for actuating the transmitter, as denoted by arrow A, representative of disturbance or movement of soil  22  as a result of presence in or passage through of a mole or other animal in the underlying tunnel. As a result, signal  26  would be sent to and received by receiver/signal device  28 , which would emit an output signal  70  ( FIG. 1 ), which is preferably an audible signal, but which could alternatively or also be a visible or other signal such as a vibratory signal common with commercially available personal beepers.  
         [0019]     The location of actuator  50  and transmitter  24  of detector apparatus  12  within detector housing  42  of shell  30  protects those elements from adverse weather conditions, such as rain and hail, and also winds which could possibly result in false detections. The elongate contact of lower edge portions  32  and  34  with the ground also provides a stable base that when edge portions  32  and  34  are suitably spaced apart can be spaced from the broken soil of a trace such as trace  18 , such that detector apparatus  12  is not easily moved by wind, waterflow over the ground, partial collapse of the mole tunnel or softening of the ground due to saturation with water. Although apparatus  12  is relatively lightweight, the weight is distributed over the length of edge portions  32  and  34  such that apparatus  12  will not significantly sink into soft soil nor will it leave permanent visible marks on the soil. It is also thought that the ability to position detector apparatus  12  over a section of a trace such as trace  18 , without actually contacting the trace, reduces the possibility that a mole or other animal will avoid the effected portion of the trace. In this regard, it has been observed that when small sections of a trace are compacted such as due to foot or vehicular traffic, such sections are typically repaired by the mole and continue to be used. This is contemplated to be particularly true where the trace extends between habitats, or to a rich food source such as a lawn or field containing insects such as grubs and the like. By collapsing or tamping a portion of the overhead roof structure of the tunnel, it is anticipated that continued use of the tunnel will entail lifting or raising the tamped or collapsed portions by the mole or other animal, which would serve as ideal movement or disturbance for detection by the present apparatus. An advantage that should be noted here is that such repairs would constitute relatively significant movement, which would be easily detected, such that apparatus  12  would not be required to be highly sensitive. This is an advantage because it is believed that the less sensitive apparatus  12  is to movement, the lower possibility of occurrence of false detections, such as by movement of heavy trucks or equipment, wind, and even heavy footfalls, nearby lawn mowing, and the like. However, it is still contemplated that apparatus  12  could include elements capable of detecting very slight movements or disturbances of underlying soil such as could be generated by movement of a mole or other animal through an undisturbed trace  18 . In this regard, it is contemplated that the sensor or detector of apparatus  12  could use a non-soil contacting sensor or detector operable to detect movement of underlying soil, which would be adjusted or tuned so not to signal when inconsequential movements occur as a result of wind, rainfall, and the like.  
         [0020]     As another advantage, by tamping a portion of the soil overlaying a tunnel so as to be at least generally level with the adjacent soil areas, then placing apparatus  12  over the tamped portion resting on the adjacent soil, actuator  50  will be positioned at a desired, consistent elevation above the tamped soil, or could be in contact with the soil, as desired, such that no adjustment of the actuator position is required for use at different locations. In this way, apparatus  12  is easy to use and can be expected to obtain consistent results. If adjustment is necessary or desired, the position of actuator  50  can be changed and consistent results will be obtained as long as the soil is prepared in generally the same way and the apparatus is used in the same manner. As another possible advantage, it is contemplated that utilization of an elongate covering structure, such as shell  30 , serves as a cover over a collapsed or tamped down portion of a trace which makes it more likely to be repaired, as the sky is not directly visible and thus the mole or other animal would be less repelled by sunlight, rain, wind, and possible predators, such as birds and the like. Here, however, it should be noted that it is contemplated that, as an alternative to shell  30 , a more open, lighter structure, such as one or more thin legs, pegs, or the like could be utilized for supporting actuator  50  and transmitter  24 , which can be held in position by spiking or the like.  
         [0021]     As still another advantage, the commercially available transmitter and receiver/signal devices such as those set forth above purchasable together as a unit, for instance, from Desa International, Inc., of Bowling Green, Ky., U.S.A., can be selectably operable over more than one transmitting and receiving frequency, such that several of the present detectors can be used simultaneously in the same transmitting area. Additionally, the receiver/signal devices can have one or more selectable audible signal outputs, such that if several are used, detection of movement in a particular tunnel can be discerned by a different audible signal. Still further, it is contemplated that in addition to, or as an alternative to, the receiver/signal device disclosed above, the detector device of the invention could include a signal device, preferably one such as a signal light that when activated would signal a human when present nearby but not alarm a mole or other animal moving in an underlying tunnel. In this way a user, upon hearing an audible tone indicative of mole activity in one of several tunnels could proceed to that tunnel with the activated signal device.  
         [0022]     To facilitate determining the whereabouts of a mole or other animal in a tunnel over which apparatus  12  is used, or to allow better determining which of several tunnels a mole is in, one or more other small visible portions of the tunnel or tunnels can also be tamped down in the vicinity of apparatus  12  so that when the detection signal is emitted and a user proceeds to the area, visible repairs cam provide clues as to which direction the mole has traveled from. If the person reaches the detector quickly, the mole or other animal will likely be in the tunnel quite near or still beneath the detector and the person can simply plunge the blade of a shovel, pick, or the forks of a pitch fork or other lethal device through the soil into the tunnel to kill the mole or other animal or unearth the mole for trapping or killing. Thus, apparatus  12  can be used without danger to children and pets and without unnaturally disturbing the soil. If the animal is killed in place in its tunnel, it can be left there to decompose or be eaten by predators. If it is unearthed, the only soil damage is a shovel mark or a small amount of overturned soil, which can be easily returned to it original place. No extensive digging of a mole tunnel is required and once the mole has been eliminated, the tunnel system can be allowed to return to its original state or can be tamped down as desired. As another advantage, the exterior of apparatus  12  can be decorative, for instance, so as to resemble a lawn ornament, or a natural stone, rock or plant.  
         [0023]     Thus, there has been shown and described a novel mole detector, which overcomes many of the problems set forth above. It will be apparent, however, to those familiar in the art, that many changes, variations, modifications, and other uses and applications for the subject device are possible. All such changes, variations, modifications, and other uses and applications that do not depart from the spirit and scope of the invention are deemed to be covered by the invention which is limited only by the claims which follow.