Abstract:
A cargo handling system for cargo compartments utilizes a cargo container which rides along restraining guide rails and on top of rollers situated within and projecting slightly above structural members which are attached to roller possessing cross tracks. The cargo handling system utilizes an omni directional panel just inside the cargo door to facilitate loading, unloading, and rotational alignment of the cargo containers with the guide rails and rollers. Cargo locks situated within the roller channels and the omni directional panel secure the cargo containers in a longitudinal direction of the aircraft fuselage while a side latch within the omni directional panel secures cargo containers vertically, and in a lateral direction. An automatic anti-rollout restraint prevents the cargo container from rolling out of the aircraft while the cargo containers are being loaded or unloaded. Optionally, a power drive unit automatically moves the cargo containers along the rollers.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to a containerized cargo handling system and, more particularly, to a containerized cargo handling system for aircraft cargo compartments.  
         BACKGROUND OF THE INVENTION  
         [0002]    Cargo handling systems (CHS) are typically used in a variety of applications to move or situate cargo in a particular area whether the system moves cargo on the ground or within one of many different vehicles such as a ship, truck, or aircraft. While current aircraft cargo handling systems or methods have generally proven to be satisfactory for their applications, each is associated with its share of limitations.  
           [0003]    One such limitation pertaining to cargo loading and associated cargo packing within aircraft cargo compartments is the extraordinary amount of manual labor necessary to efficiently load an airplane cargo compartment. Due to a variety of cargo package sizes, maximizing the cargo compartment volume proves to be particularly tedious. The problem of efficiently utilizing the volume of aircraft cargo compartments has been addressed by utilizing manual labor to enter the cargo compartment to situate and precisely pack the cargo compartment to ensure that cargo compartment volume is efficiently utilized.  
           [0004]    Another problem associated with aircraft CHS relates to securing the cargo in its stowed position. Securing cargo within an aircraft cargo compartment is important since cargo shifting occurs during aircraft takeoffs and landings, mid-flight ascents and descents and during a multitude of random in-flight air-turbulent events. The problem of securing the multitude of different cargo package sizes within cargo compartments is presently solved by securing cargo packages with tie-down cords or nets that are attached to the interior of the aircraft fuselage. These cords and nets are typically placed on each individual package or by securing zones throughout the cargo compartment. Despite this security measure, cargo shifting results since the cargo boxes, many of them being standard cardboard, abut each other, and a shift in one cargo box usually results in a shift of an adjacent box. This horizontal and vertical shifting causes cargo loads to become unsecured, potentially resulting in cargo damage.  
           [0005]    Prior art solutions to the above problems encompass the implementation of a conveyor system built into the floor of a particular aircraft cargo compartment. This conveyor system is typically referred to within the airline cargo industry as a “magic carpet”. While the magic carpet may move cargo packages across an aircraft cargo compartment floor more quickly, manual labor must still be used to situate the cargo within the cargo compartment. Additionally, the system is inflexible because it is fixed within the cargo compartment floor and cannot be removed or altered without drastic changes to the aircraft floor. Additionally, while the task of loading an aircraft cargo compartment is accomplished from an aircraft cargo door with the magic carpet moving the packages along the cargo compartment floor, cargo personnel are still necessary to cure cargo jams and to reorient packages that become lodged on the conveyor or loaded inefficiently. Additionally, the magic carpet does not alleviate the problem of making efficient use of a cargo compartment from the cargo floor to the cargo ceiling. This task is still accomplished with manual labor. Furthermore, the magic carpet is not cost effective because the system is built into the floor of the aircraft cargo compartment and presents not only a high installation or purchase cost, but also high maintenance costs since the system employs a multitude of moving parts consisting of electrically actuated motors or hydraulic systems, many of which are located under the cargo compartment floor.  
           [0006]    Still yet another problem associated with cargo loading systems is that all loading typically takes place piece by piece at an aircraft cargo door. This presents several problems. First, cargo loading must be done in inclimate weather causing airline personnel to brave the elements for particularly long periods of time depending upon the number of packages to be loaded. Second, the cargo may also be subjected to the elements potentially causing cargo damage. Whether or not the particular aircraft is equipped with a magic carpet, the packages must still be placed individually into the aircraft.  
           [0007]    Accordingly, there is a need for a cargo handling system that does not suffer from the above limitations.  
         SUMMARY OF THE INVENTION  
         [0008]    In accordance with the teachings of the present invention, a cargo handling system (CHS) for aircraft cargo compartments is disclosed. The system provides a plurality of structural or roller channels that contain a plurality of rollers on which a cargo container travels. The system also provides a plurality of roller-containing cross channels, transversely situated on the cargo compartment floor, to connect and provide rigidity to the structural channels and secure the CHS to an underlying aircraft support structure. Additionally, the CHS provides an omni directional panel connected to the structural channels and situated at a cargo compartment door. Furthermore, the CHS provides a cargo container with a lower, side recession to interact with guide rails attached to the CHS and prevent the cargo container from shifting side to side (transverse to the roller direction) and vertically within the cargo compartment. Also restricting movement and part of the CHS are a series of cargo locks that hold each cargo container in place with respect to aircraft forward and aft directions, a side latch to secure the cargo containers near the cargo compartment door, and an anti-rollout restraint to prevent the cargo containers from rolling outboard of the aircraft upon loading and unloading. Finally, the CHS contains an optional power drive unit (PDU) to assist in moving the cargo containers deeper into and out of the cargo compartment.  
           [0009]    Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]    The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:  
         [0011]    [0011]FIG. 1 is a side view of a passenger or freighter aircraft with the locations of exemplary cargo compartments shown in phantom;  
         [0012]    [0012]FIG. 2 is a plan view of a cargo handling system according to the principles of the present invention;  
         [0013]    [0013]FIG. 3 is a perspective view of a cargo compartment containing a cargo handling system according to the principles of the present invention;  
         [0014]    [0014]FIG. 4 is an enlarged perspective view of a cargo compartment showing an optional power drive unit according to the principles of the present invention;  
         [0015]    [0015]FIG. 5 is an enlarged perspective view of an omni directional panel showing an omnidirectional roller and a cargo lock according to the principles of the present invention;  
         [0016]    [0016]FIG. 6 is a perspective view of an omni directional panel showing a side latch, rollers, and an anti-rollout restraint according to the principles of the present invention;  
         [0017]    [0017]FIG. 7 is an enlarged view of a caster roller according to the principles of the present invention;  
         [0018]    [0018]FIG. 8 is a perspective view of a cargo container according to the principles of the present invention;  
         [0019]    [0019]FIG. 9 is a front view of the cargo container of FIG. 8 illustrating how the cargo container rides on the rollers and interacts with the guide rails of the present invention;  
         [0020]    [0020]FIG. 10 is an enlarged view of the encircled area  10  of FIG. 9;  
         [0021]    [0021]FIG. 11 is a side view of a cargo container of FIG. 8 illustrating how the cargo locks engage to secure a cargo container;  
         [0022]    [0022]FIG. 12 is an enlarged view of a cross channel showing two rollers and a guide rail according to the principles of the present invention;  
         [0023]    [0023]FIG. 13 is a plan view of a cargo compartment showing representative cargo containers in their stowed and secured positions;  
         [0024]    [0024]FIG. 14 is a perspective view of the cargo lock device shown in the retracted position;  
         [0025]    [0025]FIG. 15 is a side view of the cargo lock device of FIG. 14 shown in the retracted position;  
         [0026]    [0026]FIG. 16 is a side view of the cargo lock device in a partially extended position according to the principles of the present invention;  
         [0027]    [0027]FIG. 17 is a side view of the cargo lock device in a fully extended position according to the principles of the present invention;  
         [0028]    [0028]FIG. 18 is a side view of the anti-rollout restraint according to the principles of the present invention;  
         [0029]    [0029]FIG. 19 is a perspective view of the side latch device shown in the latching position;  
         [0030]    [0030]FIG. 20 is a side view of the side latch device of FIG. 19 shown in the retracted position; and  
         [0031]    [0031]FIG. 21 is a side view of the side latch device shown in the latching position. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0032]    The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.  
         [0033]    [0033]FIG. 1 shows a representative commercial passenger or freighter aircraft  10  with a fuselage  12 , aircraft forward portion  14 , and aircraft aft portion  16 . Additionally, the locations of forward cargo compartment  18 , and aft cargo compartment  20  with cargo doors  22  and  24 , respectively, each house a cargo handling system (CHS)  26  (FIG. 2) of the present invention. Aft cargo compartment  20  will be used as the representative cargo compartment for the basis of this detailed discussion, although those skilled in the art will recognize that nearly any available area of the aircraft  10  may serve as a cargo compartment and possess the potential of accepting a CHS  26  according to the principles of the present invention.  
         [0034]    Generally, the aft cargo compartment  20  possesses a CHS  26  as shown in FIGS.  2 - 4 . With continued reference to FIGS.  2 - 4 , the CHS  26  of the present invention mounts to a cargo compartment floor  28  which is supported by an aircraft substructure  30  (FIG. 3). The CHS  26  includes a plurality of structural channels  32 , also referred to as roller channels, generally in the form of a C-channel. A plurality of cross channels  34 , extend perpendicular to channels  32 . An omni directional panel  36  is provided in communication with the structural channels  32 . Guide rails  38  extend along opposite sides of the cargo compartment floor  28 . A plurality of rollers  40  are disposed on the cross channels  34  and structural channels  32 . A plurality of cargo locks  42  are disposed on the structural channels  32 . In greater detail to better depict their position and operation, FIG. 5 shows a cargo lock  42  positioned in an omni directional panel  36 , along with a plurality of caster rollers  48 , also shown in the enlarged view of FIG. 7. Continuing, FIG. 6 shows an omni directional panel  36  including a side latch  44 , an anti-rollout restraint  46 , and rollers  40 . Additionally, the CHS  26  comprises at least one cargo container  50  shown in the perspective view of FIG. 8, and also in FIGS. 9, 10, and  11 . Cargo container  50  translates upon the rollers  40  of CHS  26  and caster rollers  48  of the omni directional panel  36 . The caster roller  48  is further depicted in co-pending U.S. patent application Ser. No. 09/908,159, filed on Jul. 18, 2001.  
         [0035]    With the general components of the cargo handling system  26  presented, a more detailed description of the CHS  26  and its method of operation now follows. With reference to FIGS.  1 - 2 , aft cargo compartment  20  is representative of an aircraft cargo compartment that is loaded by moving the cargo containers  50  from an outboard area  52  through a cargo door opening  54  to an inboard area  56 . When a cargo container  50  is placed into inboard area  56 , it is placed onto the caster rollers  48  of the omni directional panel  36 . While the cargo containers  50  are generally loaded onto the omni directional panel  36  in such a way as to reduce any repositioning, the caster rollers  48  are capable of rotating 360 degrees about an axis perpendicular to the cargo compartment floor  28 , therefore the cargo container  50  can be aligned with the guide rails  38  of the CHS  26 . The cargo container  50  of FIG. 8 is shown in FIGS. 9 and 10 with an associated guide rail  38  and rollers  40 . Additionally, FIG. 12 shows an enlarged view of cross channel  34  showing guide rail  38 , and rollers  40 . As can be seen from FIGS. 9 and 10, cargo container  50  includes a recess  58  which receives an upper, inwardly projecting portion  38   a  of guide rail  38 .  
         [0036]    With the operative components of the CHS  26  initially presented, a typical loading scenario depicting the interaction and function of the CHS  26  components will now be explained. With reference to FIG. 2, when cargo containers  50  move from an aircraft outboard area  52  to an aircraft inboard area  56 , they move in a lateral direction. Once inboard, the cargo container  50  is located upon the omni directional panel  36  and associated caster rollers  48 . The portion of the container  50  is adjusted in order to orient the cargo container  50  with the guide rails  38  mounted opposite the cargo door  54 .  
         [0037]    With reference to FIG. 7, caster roller  48  includes a base plate  60 , rotational plate  62 , and a plurality of bearings  64  that rotate upon a bearing shaft  66 . The rotational plate  62  rotates about a plate shaft  68  to permit 360 degree rotation of the rotational plate  62  relative to the base plate  60 . Additionally, once the cargo container  50  is inboard and aligned with the guide rail  38  opposite the cargo door opening  54 , the anti-rollout restraint  46  (FIGS.  6  and  18 ) biases upward to prevent the cargo container  50  from rolling out of the aircraft  10 . With reference to FIGS. 6 and 18, the anti-rollout restraint  46  is shown normally biased upward but easily biases downward into recessed cavity  46   a  to permit the unrestrained loading of the cargo container  50  into the aircraft  10 . The spring  46   b  biases the anti-rollout restraint  46  to a normally upright position as illustrated in FIG. 18.  
         [0038]    As shown in FIGS. 9 and 10, the cargo container  50  includes a recess  58  that accepts the inwardly projecting portion  38   a  of guide rail  38  of the CHS  26 . With the cargo container  50  loaded and aligned with the guide rail  38  opposite the cargo door  54 , the cargo container  50  is rolled deeper into and along the cargo compartment  20 . Upon passing the cargo door opening  54 , the cargo container  50  aligns with the guide rail  38  adjacent to the cargo door opening  54 . Continuing, with reference to FIGS. 2 and 3, the cargo container  50  begins to translate on the rollers  40  in the structural channels  32  and the rollers  40  in the cross channels  34 . The rollers  40  are crowned in the center as shown in FIG. 12 in order to reduce the area of contact against the cargo container  50  and ease in the rolling process. When the cargo compartment  20  is empty, the cargo container  50  moves to the end of the cargo compartment  20  and abuts against a cargo stop  70  (FIG. 3). When the cargo container  50  abuts cargo stop  70 , a cargo lock  42  can be positioned against the cargo container  50  to secure the cargo container against the cargo stop  70 . FIG. 5 shows a cargo lock  42  that pivots upwardly, as shown in FIGS.  15 - 17 , to an engaged position to prevent movement of the cargo container  50 . The cargo lock  42  includes a first arm  102  pivotally mounted about a pivot member  104  provided in the recess  106 . A second arm  108  is pivotally connected to a second pivot member  110  provided in the recess  106 . a first torsion spring  112  biases the first arm  102  to a normally horizontal position within the recess  106 . A second torsion spring  114  biases the second arm  108  toward a vertical position. The first arm  102  is generally U-shaped with each leg  116  of the U-shaped arm  102  being pivotally mounted to the pivot member  104 . Each leg  116  includes a recessed area  118  which are each engaged by a prong  120  of a fork-shaped end  122  of the second arm  108 .  
         [0039]    With reference to FIGS.  15 - 17 , the operation of the cargo latch  42  will now be described. Initially, as shown in FIG. 15, the cargo latch  42  is in a stored horizontal position. The first arm  102  is then pivoted upward (in a counterclockwise direction as illustrated in the figures). As the first arm  102  is pivoted upward, the spring  114  biases the second arm  108  in an upward direction. Each prong  120  of the fork-shaped end  122  of the second arm  108  abuts against the recess  118  provided on each leg  116  of the U-shaped arm member  102 . As the first arm  102  is pivoted backward far enough so that the recess portion  118  aligns with the shoulder portion  124  of the fork-shaped end  122 , the second arm  108  is allowed to pivot upward to the position illustrated in FIG. 17. At this position, the spring  114  biases the second arm  108  in a counterclockwise direction while the spring  112  biases the first arm  102  in a clockwise direction, thus locking the first arm  102  and second arm  108  in the upright vertical positions illustrated in FIG. 17.  
         [0040]    In order to retract the cargo latch  42 , the second arm  108  is pushed downward in order to allow the recess portion  118  to overcome the shoulder portion  124  on the fork-shaped end  122  of the second arm  108  such that the spring then biases the first arm  102  toward the horizontal position as illustrated in FIG. 15. The cargo container  50  is able to roll over a cargo lock  42  when the cargo lock  42  is in a disengaged position. FIG. 5 shows a cargo lock  42  in the omni directional panel  36 , while FIG. 3 and FIG. 11 show cargo locks  42   a  and  42   b  positioned along the structural channels  32  in order to secure each successive cargo container within the CHS  26 .  
         [0041]    With reference to FIGS. 9 and 10, as the cargo container  50  is rolled along the CHS  26 , the guide rail  38  is secured within the cargo container  50  recess  58 . This recess  58  and guide rail  38  combination secures the cargo container  50  in vertical and lateral directions during flight and also secures the cargo container  50  during loading and ensures uniform cargo container  50  alignment within the cargo compartment. After the first cargo container is loaded and secured with a cargo lock  42 , a second, third, etc. cargo container may be loaded and secured with the cargo locks  42  until the cargo compartment is full. FIG. 13 illustrates a fully loaded compartment  72  with letters A-I representing successively loaded cargo containers.  
         [0042]    When the last cargo containers B and A are loaded into the cargo compartment  20 , cargo locks  42  in the omni directional panel  36  are employed. Recalling that cargo locks  42  in the structural channels  32  and omni directional panel  36  prevent movement of the cargo containers  50  in the forward and aft directions, while the guide rails  38  prevent movement in the vertical and lateral directions, the side latches  44  (FIG. 6) of the omni directional panel  36  are used to secure the cargo containers  50  in a vertical direction during flight. Therefore, the side latches  44  are also employed upon completely loading the cargo compartment  20 .  
         [0043]    With reference to FIGS.  19 - 21 , the side latch  44  includes a latch plate  130  pivotally mounted about a first pivot member  132 . The latch plate  130  is mounted to the pivot member  132  at a first end thereof and includes a detent portion  134  at the first end. The latch plate  130  includes a second end  136  having a hook-shaped end portion which extends generally perpendicular to the latch plate  130 . A spring  140  is provided for biasing the latch plate  130  toward a horizontal position as shown in FIG. 20. A locking lever  142  is pivotally mounted to a second pivot member  144 . A second spring member  146  biases the locking member  142  to rotate in a counterclockwise direction as illustrated in the figures. The latch plate  130  can be pivoted from its horizontal position as shown in FIG. 20 to an upright vertical position (as shown in FIG. 21) against the biasing force of the spring  140 . As the detent  134  becomes aligned with the locking lever  142 , the locking lever  142  pivots upward by the biasing force of the spring  146  to a locking position in order to lock the latch plate  130  in the horizontal position. A release flange  150  is fixably attached to the locking lever  142  and can be pushed downward, as illustrated in phantom in FIG. 21, in order to disengage the locking lever  142  from the detent  134  such that the latch plate  130  is allowed to move to its horizontal position under the bias of spring  140 . Thus, the side latch  44  can be operated between the stored position, as shown in FIG. 20, and the latching position, as shown in FIG. 21.  
         [0044]    The above-described CHS is manual, however, optional power drive units (PDU) may be employed to eliminate the necessity of a person from having to board the aircraft  10  and move the cargo containers  50  along the CHS  26 . With reference to FIG. 4, an optional PDU  74  and associated power roller  76  is available for mounting within representative power cavity  78  of the cargo compartment floor  28 . FIG. 3 shows additional power cavities  78  along the CHS  26  between the structural channels  32 . With reference to FIG. 13, PDUs are employed to apply a force against the cargo containers to secure them against the cargo stop  70  (in the case of cargo container  1 ), or an adjacent cargo container C-H. Cargo containers A and B are moved manually due to their location relative to the cargo door  54 .  
         [0045]    The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.