Abstract:
A live animal trap for capturing and restraining a small animal comprises a rectangular mesh cage having an open front sized to admit an animal to be trapped, and a trap door hingedly affixed to the cage and movable between raised and lowered positions, respectively, permitting entry to and preventing escape from the cage. Embodiments are disclosed of gravity and/or spring assisted latching and tripping structures for releasably securing the trap door in the open position and responsive to an animal seeking to get to bait in the back of the cage. In one, a spring assisted brace member is hingedly affixed to and drives the lower end of the trap door into the closed position. In another, a multipurpose guide collar locks and drives the trap door in and for movement between the raised and lowered positions, and assists in animal release and in resetting of the trap.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This Application is a completion application based on co-pending U.S. Provisional Application Ser. No. 60/196,723, filed Apr. 13, 2000, having the title “Animal Trap”, the disclosure of which is hereby specifically incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates, in general, to improvements in traps for small animals in the form of a cage structure for trapping and holding, without harming, the animal whereby the animal can be relocated to another area. More particularly, the invention relates to spring and gravity actuated closure arrangements for use in such cage structures. 
     2. Description of Prior Art 
     Animal traps comprising a cage of metal mesh and constructed with locking means for locking a trap door in a closed position are known. The animal trap typically includes a tripping mechanism that is tripped when the animal is lured into the cage to obtain bait placed therein and operates to cause the trap door to move between an open position and into a closed position. A locking mechanism cooperates to releasably lock the trap door in the closed position. 
     In some animal traps, the trap door falls by gravity and into engagement with a lock member to ensure that the door does not open and allow the trapped animal to escape. These traps are simple in operation and construction. 
     However, since animal traps are typically placed outside and are subject to the environment, they can rust or otherwise be subject to mud or other material. A trap door that relies solely on gravity to move into its closed position might have to rely on its ability to overcome the problems associated with its prolonged exposure to the environment and may not close at all or only partially, thereby permitting the animal to escape from the cage. 
     To overcome certain problems associated with the environment, some animal traps have arranged springs and linkage rods together with one another and with the trap door whereby to positively bias the trap door into the closed position or a latch member into a locked relation with the trap door. Depending on the spring and trap door arrangement, a biased trap door could close about and harm the animal. 
     There is always a need for improvement in animal traps that enable a small animal to be trapped without harm. 
     An object of this invention is the provision of an animal trap that enables small animals to be safely trapped in a cage for relocation to another place. 
     Another object of this invention is an animal trap having an improved closure, tripping and locking means for containing an animal that enters the trap. 
     Still another object of this invention is the provision of an animal trap for small animals, the trap including a simple yet effective tripping mechanism that is actuated by the animal entering the trap. 
     SUMMARY OF THE INVENTION 
     According to a first embodiment of this invention there is provided an animal trap including a tripping mechanism operably connected to a spring-loaded closure structure that cooperates with a trap door to provide positive and rapid snap closure of the trap door without harming the animal. In particular, the animal trap comprises: 
     a cage having a top, a bottom, a back, and side walls of mesh or like material, the side walls joining the top, bottom, and back walls whereby to form an enclosure having a front opening enterable by an animal, 
     a trap door having a top edge portion hingedly affixed to the top of the cage and a bottom edge portion, said trap door being rotatable between a raised cage open position permitting entry into the cage and into a lowered cage closed position wherein the trap door is in covering relation with the front opening, this door being sized substantially equal to the size of the first opening; 
     a trip lever hingedly affixed to the cage and disposed within the enclosure, the trip lever being tripped by an animal trying to get to bait in the back of the cage; 
     a trip rod rotatably mounted to said cage and including a catch member for engaging and maintaining the trap door in the raised cage open position, 
     a linkage structure connecting the trip rod to the trip lever, and 
     a spring operated locking structure for biasing the trap door from said raised position and toward said lowered position and releasably maintaining the trap door in the lowered cage closed position, 
     whereby movement of the trip lever is transmitted by the linkage structure to the trip rod causing the trip rod to rotate and the catch member to be dislodged from its engagement with the trap door whereupon gravity and the spring operated locking structure act to drive the trap door into closing relation with the front opening. 
     The spring operated locking structure comprises a brace member having a first end portion hingedly connected to the trap door proximate to the bottom edge portion thereof and a second end portion, a spring member connecting the bottom edge portion of the trap door to the brace member, and a catch member proximate to the top of the cage for engaging the second end portion of the brace member. In the lowered cage closed position, the free end of the brace member positions the hinged end thereof so as to drive the bottom edge portion of the trap door downwardly and into the cage closed position. 
     Preferably, the cage includes a front wall of mesh or like material and is provided with a central opening for the animal to enter, the front wall being adapted to be covered by the trap door when in the lowered cage closed position. Preferably, the front wall is disposed at an acute angle to the bottom wall, generally between about 40°-60° thereto. In a particular embodiment, the front wall is at about 45° to the bottom wall and forms the hypotenuse of a 45° right triangle. 
     In the raised cage open position, the brace member is folded onto the trap door and disposed between the trap door and the top wall of the cage. The second end of the brace member abuts the top wall and cooperates with the spring member (and gravity) to force the brace member and trap door downwardly and away from the top wall of the cage. Substantially simultaneously with release of the trap door, the force of gravity pulls the trap door downwardly, and the spring pulls the brace member away from its overlapped relation with the trap door. The spring forces the free end of the brace member against the top wall of the cage and into engagement with the catch member, the free end acting to drive the trap door (to which the hinged end of the brace member is connected) downwardly. 
     In the lowered cage closed position, the brace member and the trap door are at an acute angle to one another. The brace member has its second end portion positioned against the top wall and its first edge portion forcing the trap door into the closed position. 
     According to a second embodiment of this invention there is provided an animal trap including tripping and locking mechanisms operably connected to a closure structure that includes a trap door which operates under gravity to move between a raised position (generally parallel to the top wall of the cage) and to a lowered position (generally vertically extending between the top and bottom walls) to provide positive and rapid closure of the trap door without harming the animal. Similar to the first embodiment, the animal trap of this embodiment comprises a generally rectangularly configured cage comprised of walls of mesh-like construction or material otherwise apertured and having a front opening by which an animal can enter the cage to get to bait in the back of the enclosure. 
     More particularly, the animal trap of this embodiment comprises: 
     a pair of laterally spaced parallel guide posts, the posts extending vertically between the top and bottom walls proximate to the open front of the cage, 
     a trap door hingedly affixed to the top of the cage at the front thereof and movable between raised and lowered positions, the trap door having a bottom edge adapted to be proximate to the top and bottom walls, respectively, when the trap door is in the raised and lowered positions, respectively, 
     a guide collar connected to the trap door and to the guide posts, the guide collar being mounted to the guide posts for movement relative thereto and between said positions and locking the trap door in the lowered position, 
     a lock wheel for releasably holding the guide collar in the raised position and the trap door proximate to the top wall of the cage, the lock wheel being rotatable from a holding position for holding the guide collar in the raised position to a releasing position for releasing the guide collar and trap door, 
     a tripper mechanism responsive to the animal entering the cage and operable to release the lock wheel for rotation between said holding and releasing positions, and 
     a resetting mechanism for resetting the trap door in the raised position, the resetting mechanism including at least a portion of said guide collar acting on said lock wheel to rotate said lock wheel into the holding position. 
     A feature of this invention is an animal trap comprised of screen, open mesh, expanded metal and the like construction, which enables wind to pass through without the cage tumbling and allows the bait to be seen and detected by an animal. 
     Another feature of this invention is an animal trap which efficiently and safely captures small animals, such as rats, skunks, raccoons and other varmints or the like, for relocation. 
     A desirable feature of the gravity operated and/or spring assisted animal cages described herein above is the simplicity of design, trap setting, ease of animal release, and trap resetting. In a first embodiment, re-setting is staged by the brace member being disengaged and folded over onto the trap door and the combination snapped into the raised position. In a second embodiment, the cage is merely turned 180° over onto itself, causing the guide collar which is coupled to the trap door, to move the trap door back to the raised position and lockingly engage with a lock member. 
     For a more complete understanding of the invention, reference is made to the following detailed description and accompanying drawings. In the drawings, like reference characters refer to like parts throughout the several views in which: 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIGS. 1 and 2 are perspective views, looking rearwardly and forwardly, respectively, of a first embodiment of an animal trap according to the present invention, the animal trap including a closure arrangement and trap door therefor that is spring-loaded and operates under the force of gravity. 
     FIGS. 3A and 3B are side and front elevation views of the animal trap, with portions of side wall material removed to show detail, illustrating a trip lock arrangement maintaining a trap door in a raised (cage open) open position whereby to permit animal entry into the cage. 
     FIGS. 4A and 4B are side and front elevation views of the animal trap, corresponding to FIGS. 3A and 3B, respectively, illustrating the trip lock arrangement and the trap door in a lowered (cage closed) position whereby to prevent the animal escaping from the cage. 
     FIGS. 5 and 6 are perspective views, looking rearwardly and forwardly, respectively, of a second embodiment of an animal trap according to the present invention, the animal trap including a closure arrangement and a trap door therefor that uses the force of gravity to close and reset the trap door. 
     FIGS. 7A and 7B are side and front elevation views, respectively, of the animal trap of FIGS. 5 and 6 and illustrate a trip lock arrangement maintaining the trap door in a raised (cage open) open position whereby to permit animal entry into the cage. 
     FIGS. 8A and 8B are side and front elevation views of the animal trap, corresponding to FIGS. 7A and 7B, respectively, and illustrate the trip lock arrangement and the trap door in a lowered (cage closed) position to prevent the animal from escaping from the cage. 
     FIGS. 9A and 9B are partial cutaway views corresponding to FIGS. 7A and 7B, respectively, and show the trap door and a latch member in the raised (cage open) position, and the trap door after having been released and moving downwardly towards the lowered (cage closed) position. 
     FIGS. 10 and 11 are partial views of a modified trap door assembly in a door closed and a door open position, respectively. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Turning now to the drawings, according to this invention, FIGS. 1-4 and FIGS. 5-9, respectively, illustrate preferred embodiments of an animal trap for small animals, the traps being denoted generally by the numbers  10  and  100 . As will be detailed herein below, the animal traps  10  and  100  are similar to each other in that each includes a generally rectangularly formed cage member formed of a mesh or suitably apertured material, has an opening at a front end thereof for an animal to enter, a door closure arrangement that includes a trap door that rotates under the force of gravity from a raised to a lowered position, and a trip lock arrangement that is releasably connected to the trap door and triggered by the animal. 
     The embodiments primarily differ from one another in the operation of the closure and trap door arrangement. In the animal trap  10  the trap door operates, in part, under the force of gravity and under the action of a spring member. In the animal trap  100 , the trap door closes solely under the force of gravity. 
     Turning to the first embodiment, and in particular to FIGS. 1-4, the animal trap  10  comprises an elongated, generally rectangularly shaped, mesh cage. The cage has generally parallel top and bottom walls  14  and  16  of rectangular shape, generally square front and back walls  18  and  20 , and a pair of generally parallel sidewalls  22  and  24  of rectangular shape joining the top, bottom, back and front walls. The cage or enclosure defines an interior for trapping the animal and which is enterable only through an opening  12  formed centrally of the front wall  18 . 
     Each of the walls  14 ,  16 ,  18 ,  20 ,  22  and  24  are formed by a rectangular grid of reinforcement members  26  to provide body and strength to the enclosure and by a mesh screen  28  to form a complete closure. Preferably the reinforcement members and mesh screen are comprised of steel. 
     Additionally, if desired, primarily depending on the size and nature of the animal to be trapped, the cage could be constructed in a more durable fashion. In particular, according to this invention, the walls and door of the cage may be comprised of a woven wire openwork construction, or what is oftentimes referred to in the art as “expanded” sheet metal. Expanded sheet metal is the result of a process whereby a single sheet of metal is simultaneously cut or slit and then opened by stretching the sheet whereby to produce a mesh or latticework comprised of a series of diamond-shaped openings. Desirably, the general shape of the cage enclosure can be made by the use of only a single sheet of expanded metal that is provided with three 90° bends whereby to form the walls  14 ,  22 ,  16 , and  22 , and to which shape are attached the front and back walls  18  and  20 . The cage walls would be adjoined by any suitable method, such as by welding or other method known by those skilled in the art. 
     However, if suitably dimensioned, the walls and mesh could be comprised of a suitable polymeric material, wood, reed or other natural material. It is to be understood that many materials that are apertured (or comprised of a foraminous material) would suffice and be known to those skilled in the art. Importantly, the walls of the cage should be suitably apertured to enable the animal to see and smell bait placed in the interior of the cage. 
     According to this invention, the front wall  18  is at an acute angle to the bottom wall  16  and is generally disposed at an angle of about 40°-60° thereto. Preferably, the front wall  18  is at an angle of about 45° to the top and bottom walls  14  and  16  and forms the hypotenuse of a 45° right triangle. 
     A trap door  30  of generally rectangular shape and having a top and a bottom edge portion  32  and  34 , respectively, is hingedly affixed at the top edge portion  32  thereof to the front wall  18  of the cage. Preferably, the trap door  30  is constructed in a manner similar to that of the above described wall members and comprises a rectangular grid of horizontally and vertically extending reinforcement members  26  and a mesh screen  28  secured thereto. The trap door  30 , the opening  12  and the front wall  18  are generally rectangular and/or square in shape, concentric with one another, and the door dimensioned to be slightly larger than that of the opening. 
     Two or more cylindrical or ring shaped sleeves or hinge members  36  are laterally spaced and fitted about the topmost horizontally disposed reinforcement member  26  on the trap door  30  and a horizontally disposed reinforcement member  26  on the front wall  18 . By such connection, the trap door  30  is rotatably mounted to the cage for rotation relative thereto about at an axis “A”. The trap door  30  rotates between a first (cage open) position raised above the front opening  12  and generally horizontally disposed relative to the top and bottom walls  14  and  16 , and into a second (cage closed) position disposed in lowered covering relation with the front opening and partially engaged with the front wall  18 . 
     A trip lever or trip plate  38  of generally rectangular shape and having a top and a bottom edge portion  40  and  42 , respectively, is hingedly affixed at the bottom edge portion  42  thereof to the bottom wall  16  of the cage in the back of the enclosure. The trip lever or trip plate  38  is tripped (i.e., depressed) by the weight of an animal crawling thereover trying to get to bait “B” placed in the back of the cage. 
     Preferably, the bait is not attached to the trip plate. The bait would be positioned between the back wall  20  and the trip plate  38 . 
     The trip plate  38  is of similar construction as the walls and comprises a rectangular grid of reinforcement members  26  covered with mesh  28 . Two or more cylindrical or ring shaped sleeve or hinge members  36  are used to connect a reinforcement member on the bottom wall  16  and which extends laterally between the sidewalls  22  and  24  to a corresponding horizontally disposed reinforcement member on the trip lever  38 . By such mounting, the top edge portion  40  of the trip plate  38  is adapted to rotate about an axis “C” and about the plane of the bottom wall  16  and move towards the bottom wall  16  of the cage. 
     Although the trip plate  38  is shown as being angled upwardly towards the front wall, the trip plate could also angle upwardly towards the back wall  20 . Additionally, although shown as being hingedly connected to the bottom wall, the trip plate  38  could be mounted for rotation to a support bar (See FIGS. 5-9) that extends between the side walls. 
     An axially elongated trip (or actuator) rod  44  is rotatably mounted to the sidewall  22  of the cage and extends between the trap door  30  at the forward end of the cage and the trip plate  38  at the rearward end of the cage. Two or more or more cylindrical or ring shaped hinge members  36  are used to connect the trip rod  44  to a horizontally extending reinforcement member  26  forming the sidewall  22 . The trip rod  44  includes an L-shaped link or catch member  46  at the forward end thereof for seating under a side edge  48  of the trap door  30  and maintaining the trap door in the first (cage open) position. As will be described hereinbelow, rotation of the trip rod  44  about its axis “D” operates to dislodge the catch member  46  from engagement with the trap door and release the trap door for closing movement. 
     A linkage structure comprising first and second links  50  and  52  connects the trip rod  44  to the trip plate  38 . The first link  50  extends transversely from the trip rod  44  at the rearward end thereof and is generally parallel to the top wall  14  when the catch member  46  holds the trap door  30  in the cage open position. The second link  52  is arranged vertically and has a first end  54  hingedly connected to the first link  50  and a second end  56  hingedly connected to a reinforcement member  26  along the edge of the trip plate  38 . 
     A spring operated locking structure comprising a brace member  58 , a catch member  60  and a coil spring  62  is provided for biasing the trap door  30  towards the second (cage closed) position in covering relation to the opening  12  and releasably maintaining the trap door in the second position. 
     The brace member  58  is generally planar, rectangularly shaped, and is of similar construction as the walls and comprises a rectangular grid of reinforcement members  26  covered with mesh screen  28 . In particular, the brace member  58  has first and second edge portions  64  and  66  and is hingedly affixed at the first edge portion  64  thereof to the trap door  30  proximate the bottom end portion  34  thereof. Two or more cylindrical or ring shaped sleeve or hinge members  36  are used to connect a laterally extending reinforcement member on the trap door  30  to a laterally extending reinforcement member on the brace member  58 . 
     By hingedly mounting the first edge portion  64  to the trap door, the second edge portion  66  of the brace member  58  is adapted to rotate about an axis “E” relative to the trap door. As will be described, the brace member  58  is initially horizontally disposed between the trap door and the top wall  14  in folded, confronting relation above the trap door. Upon release, the trap door is movable by gravity and in a “springing movement” by the brace member  58  vertically downwardly and into a substantially vertical orientation, the bottom end portion  34  of the trap door being driven against the bottom wall  16  and the trap door being disposed against the front wall  20  and in covering relation with the opening  12 . 
     The catch member  60  is in the form of a pair of L-shaped catch links, which extend downwardly from the top wall  14  of the cage for engaging the second edge portion  66  of the brace member  58 . Preferably, the catch links  60  are extensions of a reinforcement member that forms part of the top wall  14 . It is to be understood, however, that the catch links could extend from the sidewalls, if desired. 
     The coil spring  62  has a first end connected to a reinforcement member of the trap door  30  at the bottom end portion thereof and a second end connected to a reinforcement member of the brace member  58 . When the trap door is in the first (cage open) position, the coil spring  62  biases the free edge portion  66  of the brace member  58  against the top wall  14  and the bottom end portion  34  of the trap door away from the top wall. Upon rotation of the actuator rod  44 , the catch member  46  is released from the trap door, and gravity causes the (free) bottom end portion  34  of the trap door to fall. The force of the coil spring  62  causes the brace member  58  to flip or swing away from the trap door, substantially simultaneously driving the second edge portion  66  of the brace member  58  towards and into engagement with the catch link(s)  60 , and the first edge portion  64  (and bottom end portion  34  of the trap door  30 ) towards the bottom wall  16 , resulting in the brace member  58  forcing the trap door downwardly and against the front wall  18 . 
     In the first position, the brace member  58  is folded onto the trap door  30  and squeezed between the trap door  30  and the top wall  14  of the cage, the top wall  14 , the brace member  58  and the trap door  30  being generally parallel to one another. The free end or second edge portion  66  of the brace member  58  is spring loaded or biased by the coil spring  62  against the top wall  14  thereby urging the trap door  30  and the brace member  58  away from the top wall  14 . The coil spring  62 , acting proximate to the hinged connection between the brace member  58  and the trap door  30 , urges the brace member and the trap door downwardly and away from the top wall  14  of the cage. The coil spring  62  acts to rotate or pull the brace member  58  away from its overlapped relation with the trap door and drive the trap door into the second position against the front wall  18 . 
     In the second (cage closed) position, the brace member  58  and the trap door  30  are at an acute angle to one another. As noted above, the front wall  18  forms the hypotenuse and the brace member  58  and trap door  30  the legs of a 45° right triangle to provide for maximum force against the trap door. The brace member  58  is generally vertically disposed with its second edge portion  66  positioned proximate the top wall  14  and engaged by the L-shaped catch members  60  formed with the cage structure and its first edge portion  64  forcing the trap door into the closed position. 
     In operation, the user would place bait “B” in the back of the cage, between the back wall  20  and the trip plate  38 . The animal would enter the cage through the front opening  12  and proceed to the bait, stepping onto the trip plate  38 , the weight of the animal causing the trip plate to move in a downwardly direction “F” towards the bottom wall  16  of the cage. 
     Downward rotation of the trip plate  38  is transmitted by the link  52  to the trip rod  44  via the first link  50  at the rearward end of the trip rod  44 . Due to its hinged connection, the link  50  rotates (i.e., moves) in a downwardly direction “G” and the trip rod  44  rotates relative to is axis “D”, causing the forward end thereof to rotate and the catch link  46  to rotate in the direction “H” and be dislodged from its engagement with the side edge  48  of the trap door  30  whereupon gravity and the coil spring  62  act to drive the trap door downwardly and into closing relation against the front opening  12 . 
     Simultaneously with release of the trap door, the free edge portion  66  of the brace member  58  drives the free end  34  of the trap door downwardly away from the top wall  14 , springs upwardly and away from the trap door, and is captivated in the catch links  60  extending from the top wall  14 . The hinged first edge portion  64  of the brace member  58  drives the trap door downwardly against the front wall  18 . The acutely angled front wall  18  and relationship between the trap door and brace member result in the brace member being generally vertically disposed with the hinged end of the brace member driving the free end of the trap door firmly into a closed position. 
     To open or reset the animal trap, the user substantially simultaneously forces and rotates the brace member  58  away from the catch links  60  and towards the front wall  18  and the trap door towards the top wall. Sufficient upward movement will bring the trap door into lodged engagement with the catch link  46 . 
     Turning now to FIGS. 5-9, a second embodiment of an animal trap according to this invention, generally indicated by the number  100 , comprises an elongated, generally rectangularly shaped cage that is closed on five of its sides with the side corresponding to the front wall thereof defining a closable front opening  112  sized to permit entry of a small animal into the cage to obtain bait “B” placed in the rearward (interior) end of the cage. 
     In particular, the cage is formed by a top and a bottom wall  114  and  116 , a pair of opposed sidewalls  122  and  124 , and a back wall  120 . A trap door  130  for closing the front opening  112  is hingedly connected to the cage by an axially elongated support bar  136  and is adapted to rotate relative to the support bar and the front opening from a raised (cage open) position to a lowered (cage closed) position. In the raised position, as shown by reference to FIGS. 5,  6 ,  7 A,  7 B, and  9 A, the trap door is generally horizontally disposed relative to the top and bottom walls  114  and  116  and in juxtaposition with the top wall  114 . In the lowered position, as shown by reference to FIGS. 8A and 9B, the trap door is at an acute angle to the top and bottom walls. 
     Preferably, the walls  114 ,  116 ,  122 ,  124  and  120  of the cage and the trap door  130  are formed of expanded sheet metal, as described hereinabove. In such construction, a single continuous planar rectangular sheet of expanded metal is bent to form the walls  114 ,  122 ,  116  and  124 , and the two free edges of the sheet thus bent are adjoined (e.g., welded together) to form a rectangular shell structure that is fixedly secured (e.g., welded) to the back wall  120  and in encircling relation thereto whereby to form the rectangular cage having an open front. 
     The trap door  130  is generally planar, rectangularly shaped, and includes a top edge portion  132  that is hingedly secured to the support bar  136  for rotation relative thereto and a bottom edge portion  134 . The support bar  136  has its opposite axial ends  136   a  and  136   b , respectively, secured to the sidewalls  122  and  124  whereby to be disposed in generally parallel relation to the top and bottom walls  114  and  116  and to position the top edge portion  132  of the trap door proximate to the top wall  114 . 
     In the embodiment shown, the length of the trap door (i.e., the distance between the opposite edge portions  132  and  134 ) is somewhat greater than the vertical height (i.e., the distance between the top and bottom walls  114  and  116 ) of the cage, and the width of the trap door is less than the distance between the sidewalls  122  and  124 . As such, when mounted, the trap door may swing relative to the cage walls and between the raised and lowered positions. 
     When in the lowered (or cage closed) position, the trap door is oriented at an acute angle to the top and bottom walls  114  and  116 . The bottom edge portion  134  of the trap door engages the bottom wall  116  and the trap door angles inwardly and upwardly towards the top wall. 
     As will be appreciated from the discussion herein below, a steeper angle will contribute to a trap door closure that is more difficult for the animal to dislodge. However, if too steep, the door may not rotate rapidly and function in the manner of a drop gate. Preferably, the trap door is disposed at an angle of between 60° and 80° relative to the bottom wall  116 . More preferably, the trap door is at an acute angle of about 75° to the bottom wall. 
     A guide structure is provided for guiding the trap door between the raised and lowered positions. Preferably, the guide structure includes a pair of axially elongated guide rods  168  and  170  and a generally rectangularly shaped guide collar  172 . 
     The guide rods  168  and  170 , respectively, have opposite end portions  168   a  and  168   b  and  170   a  and  170   b  that are connected to the cage and space the axially extending portion of each guide rod so as to be forwardly from the front opening of the cage and in parallel relation to one another and to the sidewalls  122  and  124 . As shown, the end portions  168   a  and  170   a , and  168   b  and  170   b , respectively, are fixedly connected to the top and bottom walls  114  and  116 . As connected, the axes of the guide rods are generally perpendicular to respective planes including the top and bottom walls  114  and  116  and the axis of the support bar. If desired, the end portions of the guide rods could be connected to the sidewalls  122  and  124   
     In the embodiment shown, a folded-over reinforcement plate (or frame) (not shown) is secured to the edges of the trap door and also to the free end portions of the walls  114 ,  122 ,  116 , and  124  of the expanded metal sheet structure whereby to reinforce (or rigidify) the trap door  130  and the front opening  112 . Preferably, the opposite end portions  168   a,    168   b  and  170   a,    170   b  of the respective guide rods  168  and  170  are fixedly connected to the portion of the reinforcement frame that extends along the top and bottom walls  114  and  116 . 
     The guide collar  172  is adapted to connect the trap door  130  to the guide rods  168  and  170  and constrain the combined vertical and rotational movement of the trap door relative to the front opening  112  of the cage. The guide collar  172  comprises a pair of axially elongated guide beams  174  and  176  connected to a pair of centrally bored guide sleeves  178  whereby to form a rectangular shaped opening sized to fit about the trap door. The guide sleeves  178  are mounted to a respective guide rod  168  and  170  for sliding movement therealong. 
     In the embodiment shown, when the guide sleeves  178  are mounted to the guide rods, the guide beams  174  and  176  are generally horizontally disposed and in parallel spaced apart relation with one another and with the top and bottom walls  114  and  116 . The guide beams  174  and  176  are in juxtaposition with the exterior and interior faces of the trap door (i.e., distal and proximate to the cage interior) with the guide rods spacing the guide beam  174  outwardly from the front opening of the cage. 
     As an important feature of this embodiment, the guide beam  174  serves several functions. First, the guide beam  174  functions as a handle for carrying and positioning the cage. The guide beam or handle  174  enables the user to carry the cage to a location for trapping an animal and also to carry the cage with a trapped animal to a remote location for release. Further, the guide beam or handle enables the user to position or otherwise maneuver the cage, such as for turning the cage 180° onto itself and positioning the top wall  114  so as to be engaging the ground, such as for effectuating release of an animal and resetting of the cage. 
     Second, the guide beam  174  provides the user with a way to set/reset the trap. The user grasps the handle and lifts the guide collar  172  upwardly, causing the interiorly disposed guide beam  176  to engage the rear (interiorly facing) side of the trap door and progressively cam the trap door upwardly, enabling the user to access an actuator rod  140 , a release plate  164 , and a coil spring  162  therewithin—useful in setting/resetting the trap. The trap setting, resetting and/or trap release operation is described in greater detail herein below. 
     Preferably, a circular disc or spacer  171  is provided on the exterior guide beam  174  for spacing the axial extension of the guide beam  174  from direct contact with the exteriorly facing surface of the trap door. In some environments, problems might arise from material on the trap door resisting downward sliding movement between the guide collar and the trap door. The spacer disc  171  engages the trap door in a “point contact” and transmits gravity forces from the collar  172  to the trap door to enhance closing movement of the trap door. 
     Preferably and according to this invention, a releasable latching structure is provided for maintaining the trap door  130  in the raised or lowered positions. The latching structure comprises a trip plate  138 , a link arm  144  fixedly connected to the trip plate, the axially elongated actuator rod  146  having a rearward end portion  148  connected to the link arm  144  and a forward end portion  150 , and a latch keeper  152  releasably connectible to the forward end portion  150  of the actuator rod. The trip plate  138  is generally planar, rectangular in shape, and has a lateral width that is substantially the same as the distance between the sidewalls  122  and  124 . The trip plate is hingedly connected along a laterally extending bottom edge portion  142  thereof to a pivot bar  154  extending laterally between and connected to the sidewalls of the cage, such that a distal laterally extending top edge portion  140  of the trip plate is capable of rotation towards the bottom wall  116  of the cage. While the trip plate is preferably comprised of expanded metal, the plate may also be comprised of a mesh screen or like apertured material. 
     The link arm  144  is proximate to the pivot bar  154  and projects perpendicularly upwardly from the trip plate  138  to a connectible end portion  145 . The end portion  145  is pivotably connected to the rearward end portion  148  of the actuator rod  146  such that with downward movement (i.e., rotation) of the trip plate, the end portions  145  and  148  will rotate and/or move towards the back wall  120  of the cage and the link arm will pull the actuator rod  146  rearwardly and in a direction away from the latch keeper  152 . 
     The latch keeper  152  is connected to the cage by a plate member  153  and is proximate the top wall of the cage and the front opening thereof for releasably engaging the interior guide beam  176 . Preferably, the plate member  153  is connected to the reinforcement frame  126  forming the shape of the open end. 
     The latch keeper  152  comprises a latch housing  184  including forward and rearward housing portions  186  and  188  that form an elongated bore  190  for slidably receiving the forward end portion  150  of the actuator rod therewithin, and a U-shaped locking wheel  192 . The forward housing portion  186  is generally formed by a plate member having been folded-over to include a pair of parallel, vertically disposed, spaced-apart plate members. The locking wheel  192  is connected to the forward housing portion  186  by a pin  193  for rotation relative within the folded over plate members and between a locked and an unlocked position. 
     The locking wheel  192  includes an upper arm  194  proximate to the top wall, a central body portion provided with a locking detent  196  sized to receive the forward end portion  150  of the actuator rod, and a lower arm  198  provided with a shoulder  199  which is adapted to engage a lower edge  187  of the forward housing portion  186 . The locking detent  196  includes an axial flat and a shoulder portion and is formed by cutting away a portion of the locking wheel. 
     The lower edge  187  places a limit on the clockwise rotation (as viewed in FIG. 9A) of the lower arm  198  following release and downward movement of the trap door from the raised (cage open) position and positions the upper arm  194  for effectuating counterclockwise rotation (as viewed in FIG. 9B) of the locking wheel  192  following upward movement of the trap door from the lowered (cage closed) position back into the raised position. 
     An axially elongated, generally cylindrical coil spring  162  has opposite ends  162   a  and  162   b , respectively, connected to the rearward housing portion  188  and the actuator rod  146  and acts to pull the forward end portion  150  of the actuator rod  146  towards the locking wheel  192  for locking engagement within the locking detent  196  therein. Preferably, the actuator rod is generally cylindrical and the coil spring is circumposed around the exterior of the actuator rod. 
     According to a particular feature of this invention, an axially elongated release plate  164  is slidably connected to the actuator rod and has an end portion thereof connected to the rearward end  162   b  of the coil spring. Manual force on the release plate  164  in a direction away from the locking wheel  192  operates to axially withdraw the forward end portion  150  of the actuator rod from captured engagement within the locking detent  196  and releases the locking wheel for rotation and repositioning of the arms  194  and  198 . 
     Preferably, the forward end portion  150  and the axial flat of the detent  196  are formed with complementary tapered faces, indicated generally at  151  and  191 . Advantageously, when the trap door is in the raised (cage open) position (See FIG.  9 A), the tapered face  151  of the actuator rod provides a smooth seated engagement with the locking detent. When the trap door is in the lowered (cage closed) position (See FIG.  9 B), the tapered face  151  engages the outer periphery of the locking wheel  192  whereby to inhibit retrograde rotation of the locking wheel and maintain the locking shoulder  199  positioned against the lower edge  187  of the forward housing  186 . Further, upon resetting of the locking wheel, the tapered face  151  enhances smooth reentry into the locking detent. 
     In operation, to set the cage, the cage is taken to a location to trap an animal and the bottom wall placed on the ground. The exterior guide beam or handle  174  of the guide collar  172  is grasped and lifted vertically towards the top wall  114 . The trap door  130  is lifted slightly and the release plate  164  pulled rearwardly against the bias of the coil spring  162 , the plate pulling the actuator rod rearwardly from engagement within the locking detent, thereby releasing the locking wheel  192  for rotation. The locking shoulder  199  of the locking wheel  192  is rotated into position against the lower edge  187  of the forward housing portion  186 , thereby positioning the upper and lower arms  194  and  198  of the locking wheel to open downwardly. 
     Alternatively, to reset the trap, the cage could merely be turned over onto itself. The top wall  114  would be supported on the ground and the bottom wall  116  would be facing upwardly 
     The handle (exterior guide beam)  174  of the guide collar  172  is grasped and lifted vertically, causing the interior beam  176  to simultaneously engage and lift the trap door towards the top wall of the cage. Upon sufficient upward movement, the interior guide beam  176  engages the upper arm  194  of the locking wheel, causing the locking wheel and the upper and lower arms thereof to rotate. As a result, the locking detent  196  is rotated into alignment with the bore  190 , whereupon the forward end portion  150  of the actuator rod  146  is biased into the locking detent by the coil spring  162 . The animal trap is then set to capture an animal. 
     Bait is set into the interior of the cage, between the trip plate  138  and the back wall  120 . Because of the apertured expanded metal wall structure, a small animal can both see and smell the bait in the trap and be attracted thereto 
     A small animal enters the cage and steps on the trip plate  138 , causing the trip plate  138  to be depressed, the trip plate and link arm  144  to rotate, the actuator rod to be pulled rearwardly, and the forward end portion  150  of the actuator rod to be withdrawn from the locking detent. The locking wheel  192  is released and rotates relative to the forward housing portion  186 , causing the upper and lower arms  194  and  198  thereof to rotate and be oriented so as to open downwardly (towards the bottom wall of the cage). Rotation of the lower arm  198  releases the interior guide beam  176  of the guide collar and brings the shoulder  199  of the arm  198  into engagement with the lower edge  187  of the forward housing portion  186 , whereupon the tapered face  151  at the forward end of the actuator rod is driven against the locking shoulder to maintain the locking wheel in the rotated to position. 
     Substantially simultaneously with the actuator rod being disconnected from engagement with the locking detent, the force of gravity will act to rotate the lower arm, whereupon the guide collar and any “enhancement” weights that may have been added to the trap door and/or guide collar will cause the guide collar and the trap door to fall. The lower edge portion  134  of the trap door will come to rest on the bottom wall  116  and be positioned thereagainst by the guide collar. 
     The guide collar  172  will resist the trap door from opening as a result of any horizontal opening forces transmitted against the trap door by an animal trying to escape from the cage. That is, the collar will inhibit vertical rise of the trap door. 
     For release, the exterior guide beam or handle  174  is grasped, and used to carry the cage and trapped animal to a desired release location. The handle is again grasped and the animal cage is turned 180° such that the top wall  114  is on the ground. At this point, gravity will cause the guide collar  172  and the trap door to fall towards the top wall. The interior guide beam  176  will act against the interior wall of the trap door and gravity will urge the guide collar against the trap door and the guide collar and the trap door to fall downwardly towards the locking wheel. 
     The guide beam  176  will fall into the space between the upwardly open arms  194  and  198 , engage the upper arm  198 , and cause the locking wheel to rotate, thereby causing the locking detent to be rotated into alignment with the actuator rod. The coil spring will then bias the forward end portion of the actuator rod into the locking detent, resetting the animal cage for another trapping. 
     Accordingly, there is provided herein animal cages for capturing, without harming, small animals, the cages being simple, efficient, having positive closure arrangements that are gravity and/or gravity and spring assisted in operation. 
     Although various embodiments of the invention have been disclosed for illustrative purposes, it is to be understood that one skilled in the art can make variations and modifications without departing from the spirit of the invention. 
     In a further embodiment hereof and as shown in FIGS. 10 and 11, it is contemplated that the guide mechanism or assembly that engulfs the cage door, i.e., the guide rods, guide collar, and guide beams may be replaced with a handle assembly. 
     In accordance herewith, a cage door  210  has an outwardly and laterally extending door latch rod  212  secured thereto. The door latch rod  212  is fixed to the cage door  210  by any suitable means such as by welding or the like and is used to raise the door to a cage open position. Alternatively, the handle may be pivotally secured to the door. 
     As shown the latch mechanism, generally denoted at  214  includes a keeper assembly  216  and a rotatable wheel  218  similarly constructed to the wheel and rod  192 ,  193  discussed hereinabove. However, according hereto, the handle  212  is positively locked between the upper and lower areas  194 ,  198 , respectively, of the wheel  192 . 
     Thus, when the handle is raised it causes the door to rotate upwardly therewith. When the handle engages the arm  194  it causes rotation of the wheel  192  and the detent  196  is positively locked by the rod  150  in the manner heretofore discussed. When the plate  138  is positioned in the same manner discussed hereinabove, rotation of the wheel about the pin  193  releases the handle  212  permitting the door  210  to drop.