Abstract:
An animal caging system has a plurality of stackable support trays with integral water supply conduits to supply water sequentially to each cage and eliminate any channels of stagnant water. Each support tray includes a vertical support member that engages the vertical support members of adjacent support trays in a stacked relationship, and a number of cage docking stations arranged around the vertical support member. The vertical support member includes a water supply conduit that extends to each cage docking station of the support tray and has openings in fluid communication with corresponding openings in the water supply conduits of adjacent support trays. In this manner, the water supply conduits of the stacked vertical support members combine to supply water in a single flow path to the cage docking stations on each support tray.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates generally to the field of animal caging systems. More specifically, the present invention discloses a carousel animal caging system with a centralized water supply serving each cage.  
         [0003]     2. Statement of the Problem  
         [0004]     Caging systems have long been used in laboratories and research facilities to hold laboratory animals, such rats and mice. Such facilities often must house large numbers of laboratory animals in a relatively limited amount of space, which creates a need for adequate ventilation through all of the cages.  
         [0005]     The animals in each cage must also be supplied with water and food on a regular basis. Many conventional laboratory caging systems employ separate water bottles for each cage. This requires personnel to periodically check and refill each water bottle. Therefore a need exists for a centralized watering system to automatically dispense water to each cage.  
         [0006]     In addition, a modular design is advantageous in being able to configure the caging systems to meet the specific needs of research facilities on a customized basis. A modular design also simplifies disassembly of the caging system for cleaning or maintenance.  
         [0007]     Finally, a centralized water supply system must be periodically emptied and flushed to prevent the growth of microorganisms in the standing water in the system. This process is made simpler and more effective if the entire water supply system is a single flow path without significant branches that could trap water or not be well flushed. Therefore, it is advantageous to design a centralized water supply system with a single flow path.  
         [0008]     The prior art in the field of animal caging systems includes the following:  
                                                       Inventor   Patent No.   Issue Date                           Eagleson   3,877,420   Apr. 15, 1975           Holman   3,924,571   Dec. 9, 1975           Thomas   4,343,261   Aug. 10, 1982           Ruggieri et al.   4,365,590   Dec. 28, 1982           Catsimpoolas   4,448,150   May 15, 1984           Sheaffer et al.   4,989,545   Feb. 5, 1991           Semenuk et al.   5,996,535   Dec. 7, 1999           Gabriel et al.   6,158,387   Dec. 12, 2000           Rivard   6,257,171   Jul. 10, 2001           Frasier et al.   6,457,437   Oct. 1, 2002           Rivard   6,571,738   Jun. 3, 2003           Rivard   6,584,936   Jul. 1, 2003                      
 
         [0009]     Eagleson discloses an animal housing system having a carousel that holds a number of wedge-shaped cages. The cages are ventilated by a downward laminar air flow through a housing assembly.  
         [0010]     Catsimpoolas discloses an animal caging system with an inner carousel that holds a number of wedge-shaped cages. Each cage is removable from the cage support structure. The central core draws fresh air through the cages via cage wall perforations. An outer partial ring of animal activity stations can be used for animal weighing, feeding or experimentation.  
         [0011]     Holman, Ruggieri et al. and Semenuk et al. disclose examples of cage and rack systems that include ventilation and a water supply to each cage.  
         [0012]     Thomas, Sheaffer et al., Gabriel et al. and Frasier et al. disclose other examples of ventilated cage and rack systems.  
         [0013]     The Rivard patents disclose an animal caging system in which each cage has a separate water storage container.  
         [0014]     3. Solution to the Problem  
         [0015]     None of the prior art references discussed above show an animal caging system having a plurality of stackable support trays with integral water supply conduits to supply water to each cage. Optionally, the vertical support members of each support tray form a central plenum that can also be used for ventilation. This approach addresses the shortcoming of the prior art, as discussed above, by using a modular design to provide a centralized water supply and ventilation for each cage. In addition, the water supply can be formed as a single conduit through all of the stacked support trays to simplify draining and flushing the system.  
       SUMMARY OF THE INVENTION  
       [0016]     This invention provides an animal caging system having a plurality of stackable support trays with integral water supply conduits to supply water to each cage. Each support tray includes a vertical support member that engages the vertical support members of adjacent support trays in a stacked relationship, and a number of cage docking stations arranged around the vertical support member. The vertical support member includes a water supply conduit that extends to each cage docking station of the support tray and has openings in fluid communication with corresponding openings in the water supply conduits of adjacent support trays. In this manner, the water supply conduits of the stacked vertical support members combine to supply water to cage docking stations on each support tray.  
         [0017]     These and other advantages, features, and objects of the present invention will be more readily understood in view of the following detailed description and the drawings.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0018]     The present invention can be more readily understood in conjunction with the accompanying drawings, in which:  
         [0019]      FIG. 1  is a front perspective view of an assembled animal caging system implementing the present invention.  
         [0020]      FIG. 2  is a detail bottom perspective view of a portion of the bottom of the animal caging system.  
         [0021]      FIG. 3  is a front plan view of the animal caging system corresponding to  FIG. 1  without cages.  
         [0022]      FIG. 4  is a top perspective view of a support tray.  
         [0023]      FIG. 5  is an exploded bottom perspective view of a support tray  30 , including its ring structure  45  and a tubular connector  38 .  
         [0024]      FIG. 6  is a top view of a support tray  30  and a cage  20 .  
         [0025]      FIG. 7  is a detail vertical cross-sectional view of several support trays and cages.  
         [0026]      FIG. 8  is a bottom view of the central portion of a support tray  30  with the ring structure  45  shown in cross-section.  
         [0027]      FIG. 9  is a bottom view of the ring structure  45 .  
         [0028]      FIG. 10  is a top view of the ring structure  45 .  
         [0029]      FIG. 11  is a cross-sectional side view of the ring structure  45 .  
         [0030]      FIG. 12  is a cross-sectional side view of a cage  20  entering a docking station on a support tray  30 .  
         [0031]      FIG. 13  is a cross-sectional side view corresponding to the  FIG. 12  after the cage  20  has engaged the docking station of the support tray  30 .  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0032]     Turning to  FIG. 1 , a front perspective view is provided of an assembled animal caging system implementing the present invention. The primary components of the assembly include a support frame  10  and a plurality of stackable support trays  30 , each of which can hold a number of removable animal cages  20 .  FIG. 3  is a front plan view of the animal caging system corresponding to  FIG. 1  without cages.  
         [0033]     The details of a support tray  30  are depicted beginning with  FIGS. 4 and 5 . In particular,  FIG. 4  is a top perspective view of a support tray  30 . Each support tray  30  includes a vertical support member  40  that is designed to engage the vertical support members of adjacent support trays in a stacked relationship. For example, in the embodiment shown in  FIGS. 4, 5  and  7 , a tubular connector  38  with O-rings  39  is inserted between adjacent vertical support members  40  to create a vertical stack of support trays  30 . Alternatively, the upper and lower ends of the vertical support members  40  could be formed to directly engage one another (e.g., by insertion or threads).  
         [0034]     In the embodiment shown in the drawings, each support tray  30  has a generally-circular platter  31  surrounding the vertical support member  40  to receive and support a number of cages  20 . The platter  31  provides a plurality of docking stations for animal cages  20  arranged in a radial pattern about the vertical support member  40 . Each docking station includes a set of alignment guides (e.g., ridges  32  and guide slots  33 ) to help ensure proper alignment of the cage  20  as it is inserted into the docking station. The docking stations can be equipped with a number of stops  34  to help register the cage  20  in proper position relative to the docking station, and also to help prevent the cage  20  from becoming accidentally dislodged from the docking station.  
         [0035]     Preferably, the cages  20  are generally wedge-shaped to slide easily along the alignment guides  32 ,  33  at a docking station, and to maximize effective use of the available space on the circular support tray  30 .  FIG. 6  is a top view of a support tray  30  with a cage  20  inserted at one of its docking stations. However, a wide variety of configurations and shapes could be readily substituted for the support trays and cages. The embodiment shown in the drawings employs a single stack of vertical support members  40 , which enables the entire assembly to rotate like a carousel about a vertical axis. Alternatively, multiple stacks of vertical support members could be used for additional structural strength.  
         [0036]     The vertical support member  40  of each support tray  30  has a water supply conduit extending to each docking station. Each vertical support member  40  has upper and lower openings in fluid communication with corresponding openings in the water supply conduits of the vertical support members of adjacent support trays. The O-rings  39  of the tubular connectors  38  provide a water-tight seal between each pair of adjacent vertical support members  40 . The bottom inlet end of each vertical support member  40  seats with the upper end of the tubular connector  38  extending upward from the next support tray below. Similarly, the upper outlet end of the each vertical support member  40  seats with the lower end of the tubular connector  38  leading to the next support tray above. Thus, the water supply conduits of the stacked vertical support members  40  combine in series to form one, continuous conduit through the entire assembly supply water for distributing water to all of the cage docking stations on all of the stacked support trays.  
         [0037]     In the particular embodiment shown in the drawings, each support tray  30  has a ring structure  45  surrounding its vertical support member  40 .  FIG. 5  is an exploded bottom perspective view of a support tray  30 , including its ring structure  45  and a tubular connector  38 . The ring structure  45  can be bonded to the bottom of the remainder of the support tray  30  to define the water conduits discussed below. The vertical support member  40  for the support tray  30  essentially serves as the hub of the ring structure  45  after assembly.  FIG. 8  is a bottom view of the central portion of a support tray  30  with the ring structure  45  shown in cross-section.  FIG. 9  is a bottom view of the ring structure  45 .  FIG. 10  is a top view and  FIG. 11  is a cross-sectional side view of the ring structure  45 . This ring structure  45  passes adjacent to each of the docking stations on the support tray  30  and contains a water conduit  46  for distributing water to each docking station on the support tray  30 .  
         [0038]     A set of spokes  42  extend radially outward from the vertical support member  40  to the ring structure  45 . The spokes  42  support the ring structure  45 , the remainder of the support tray, and the cages  20  relative to the vertical support member  40 . In addition to providing structural support, the spokes  42  can also be used to distribute water from the water supply conduit in the vertical support member  40  to the water conduit  46  in the ring structure  45 . As shown in  FIGS. 6 and 8 , one of the spokes  42  can be used to carry a water supply conduit  43  and a water return conduit  44  connecting the water conduit in the vertical support member  40  to the water conduit  46  in the ring structure  45 .  
         [0039]     Thus, the water conduits  43 ,  46 , and  44  of the vertical support member  40 , spoke  42 , and ring structure  45  combine in series to form one, continuous conduit to supply water to all of the cages  20  on the support tray  30 . Within each support tray  30 , water initially flows from an adjacent support tray into the opening of the water supply conduit of the vertical support member  40  and then passes through the water supply conduit  43  in one of the spokes  42  to connect with the water conduit  46  in the ring structure  45 . The water flowing through the ring structure is available at taps  37  at each docking station for the cages  20 .  FIG. 4  includes a detail perspective view of the watering tap  37  at a typical docking station. The remaining water continues around the ring structure  45  and returns to the vertical support member  40  via the water return conduit  44  in one of the spokes  42 . This arrangement has the advantage of providing essentially a single flow path for water through each support tray  30  and through the entire assembly. This greatly simplifies draining and flushing the assembly. However, it should be understood that other alternative embodiments of the water conduit could be readily substituted.  
         [0040]     Optionally, the present invention can also be used to ventilate the cages  20 . In this embodiment, the generally annular region surrounding the vertical support members  40  and within the vertical walls and ring structures  45  of the stacked support trays  30  serves as a central ventilation plenum  50  for the entire assembly. Each docking station is equipped with a ventilation opening into the central ventilation plenum  50 . Ventilation can either be powered by a fan (not shown) or drawn by natural convection through the cages. It is important to maintain negative pressure within the ventilation plenum  50  so that ventilation air will be drawn through all of the docked cages  20  if a fan is employed. To address this concern, each docking station is equipped with a ventilation door  36  that is pushed open by a cage  20  as it is inserted into the docking station.  FIG. 4  includes a detail perspective view of a ventilation door  36 . The ventilation door  36  is spring-loaded to remain closed if the docking station is unoccupied to minimize unnecessary leakage of air into the ventilation plenum.  
         [0041]     Each animal cage  20  includes a front ventilation port  24  and a rear ventilation port  22  to allow the flow of air through the cage  20 . For example, the cage  20  can also include a number of tabs  23  projecting outward adjacent to the rear ventilation port  22  to push open the ventilation door  36  when the cage  20  is inserted into a docking station.  FIG. 12  is a cross-sectional side view of a cage  20  entering a docking station.  FIG. 13  is a cross-sectional side view after the cage  20  has engaged the docking station of the support tray. Each cage  20  also includes a watering port  26  to receive a water tap  37  extending outward from the docking station.  FIG. 7  is a detail vertical cross-sectional view of cages on several support trays showing both the watering port  26  and ventilation port  22 .  
         [0042]     A support frame  10  provides structural support for the stacked assembly of support trays  30  as shown in  FIGS. 1 through 3 . The support frame  10  is generally an open framework to provide ready access to the cages  20  stored on the stacked support trays  30 . Wheels can be attached to the base of the support frame  10  to make the unit portable. The support frame  10  includes top and bottom pivots  12  and  14  that enable the support trays  30  and cages  20  to rotate about a vertical axis. These pivots  12 ,  14  engage the tubular connectors  38  to allow rotation of the support tray assembly, and also provide a water-tight connections between external water lines and the water conduits of the stacked vertical support members  40 . For example,  FIG. 2  is a detail bottom perspective view of the bottom of the support frame  10  showing of a water supply line  15  leading to the bottom pivot  14 . Similarly, a water drain line  17  is connected to the top pivot, as shown in  FIG. 1 . During cleaning, the water supply line can be shut off, and a drain valve  16  in the water supply line  15  can be opened to drain water from the entire assembly. A bleeder valve  18  in the water drain line  17  at the top of the assembly can be used to bleed air during filling, or to allow air into the water conduits to ensure complete draining prior to cleaning.  
         [0043]     The above disclosure sets forth a number of embodiments of the present invention described in detail with respect to the accompanying drawings. Those skilled in this art will appreciate that various changes, modifications, other structural arrangements, and other embodiments could be practiced under the teachings of the present invention without departing from the scope of this invention as set forth in the following claims.