Patent Abstract:
A partition system includes partial-width partitions that are independently movable longitudinally in the trailer and independently swung to the ceiling for easy stowing. Each partition is evenly supported by a pair of rails for easy movement without undue loading of the components. One rail extends along the sidewall and another along the center of the trailer for each partition. All of the rails are part of a framework that is supported solely by the sidewalls with no loads placed on the ceiling. A lift assembly includes a lift rope, a pair of pulleys and a grip for holding the lift rope. A first pulley is generally aligned with the center of the partition to avoid substantial side loading on the pulleys during lifting and lowering of the partition. A second pulley guides the lift rope to a sidewall where it is less disruptive to the loading and unloading of goods. The grip is proximate the ceiling and avoids the formation of a taut rope segment along the sidewall. The grip has a simple construction that reliably holds the partition in the loading position as needed.

Full Description:
FIELD OF THE INVENTION 
   The present invention pertains to a partition system for subdividing a refrigerated chamber such as a truck trailer, railcar or cargo container. 
   BACKGROUND OF THE INVENTION 
   Refrigerated truck trailers and the like have long been used to transport perishable items. Insulated partitions or bulkheads have been used to subdivide the trailer interior to define chamber portions that can be maintained at different temperatures. For example, some trailers include multiple refrigerators located at the front, rear and/or midsection of the trailer&#39;s chamber. Partitions can be used to define two or three different refrigerated interior portions, each cooled to a unique temperature by one of the refrigerators. In this way, the same trailer can transport items that are desirably kept at different temperatures. Similarly, partitions can be used to enable refrigerated goods and non-refrigerated goods to be hauled in the same trailer. Partitions can also be used to improve the haul of a partially filled refrigerated truck trailer. For example, the goods can be loaded into one portion of the chamber, which is then enclosed by one or more partitions so that only a part of the trailer chamber needs to be refrigerated. Partitions can also be used to simply separate the goods to be delivered at different locations. 
   Many partitions in use today are manually fit into the truck trailer by the operator. They generally include a peripheral seal and extend laterally across the trailer chamber to subdivide the refrigerated chamber. They may at times be foldable about a vertical hinge to ease handling, installation and removal. In any event, the partitions tend to be heavy, bulky and difficult to place into their proper position. To resolve these difficulties, partitions have been shaped to correspond to only one-half of the trailer width in order to weigh less, and be more easily moved and put in place. In half-width partitions, two are placed in side-by-side abutment to subdivide the chamber. To further ease handling, some partitions have been mounted on rails for longitudinal movement in the chamber. In these constructions, the partitions are usually swung about hinges for movement between operative and loading positions. 
   In a partition system sold by ITW Insulated Products, two half-width partitions are mounted side-by-side on a single axle that is supported on each end by a trolley. Each trolley is movable along the length of a rail attached to one of the sidewalls adjacent the ceiling. In this system, the partitions are moved together along the rails to the desired longitudinal position. When the trailer is to be loaded or unloaded, the partitions are individually swung and latched to the ceiling. The half-width partitions are less weight and are thus easier to lift to the ceiling than a full width partition. Nevertheless, this system still requires the partitions to be moved together, and to be manually lifted and latched without mechanical assistance. 
   In U.S. Pat. No. 6,247,740, the partitions are individually mounted on separate axles, which are each mounted on a trolley. Each trolley moves along a rail extending across one of the sidewalls, and includes a hinge assembly that swings the partition either to the ceiling or the sidewall for loading or unloading of the trailer. The half-width partitions are more easily moved than full width partitions. However, the use of a single rail positioned along each of the sidewalls requires a relatively robust rail, trolley and axle assembly to prevent the partition from pulling from the wall. The trolley and axle assembly is also relatively complicated as compared to a single-axis hinge due to its ability to move to a loading position against the sidewall or ceiling. This system also includes lift ropes to ease lifting of the partitions when positioned along the ceiling. The ropes are hooked to anchors fixed to the sidewalls to hold the partitions in place during loading of the trailer. However, a taut segment of the lift rope extends downward along the sidewall when the partition is along the ceiling, thus risking being struck and damaged during loading of the goods into the trailer. 
   U.S. Pat. No. 6,626,625 discloses a partition system wherein half-width partitions are each separately mounted on a pair of trolleys movably attached to a plurality of spaced apart rails. One rail extends along each sidewall and two rails along the center of the ceiling. Each partition can be independently moved in a longitudinal direction and independently swung to the ceiling. Further, a lift rope is provided for lifting and lowering the partitions. The lift rope is fed through a control mechanism whereby a pivotal cam selectively holds and releases the rope as needed. However, since the pulleys and center rails are supported by the ceiling, the system can only be used in trailers constructed with ceilings able to support the necessary loads of the partition system. Moreover, operation of the cam via the lift rope requires a minimum clearance to laterally pull the rope for releasing the cam. 
   Further, goods transported in a refrigerated truck trailer are typically supported on pallets that are loaded and unloaded by fork lift trucks. The fork lift truck can at times mistakenly strike a partition set up to separate two partitioned areas. As the operators generally drive the fork lift trucks quickly, they can, at times, strike the partition with considerable force. In all current rail mounted partition systems, the partitions are fastened to the trolleys that are adapted to move along the rails. Such fastening can lead to breakage of the partitions when struck during loading or unloading of the goods. 
   SUMMARY OF THE INVENTION 
   The need exists for an improved partition system that provides the benefits sought by the industry without the previously concomitant disadvantages. 
   One object of the invention is to support the partition system solely by the sidewalls of the refrigerated chamber (e.g., a refrigerated truck trailer). In one preferred construction, a plurality of partial-width partitions are each mounted on a pair of rails for longitudinal movement, wherein the rails are part of a framework that is supported solely by the sidewalls of the trailer. In this way, an easy, reliable system is usable in refrigerated truck trailers that do not have load bearing ceilings. 
   Another object of the invention is to provide a lift assembly that is easy to use, reliable and economical. The inventive lift assembly eases movement of the partition to its loading position, forms no obstacles to loading of the goods, and requires only a few simple parts. 
   Another object of the invention is to releasably mount the partitions to trolleys supported by rails in the refrigerated chamber to avoid damage to the partition if it is struck during loading or unloading of the goods. The mounts permit the partition simply to disengage from the trolleys when struck with a certain force by a fork lift truck or other structure, thus, lessening the risk of damage and needed replacement. 
   In one preferred embodiment of the invention, the partition system includes two half-width partitions that are independently movable longitudinally in the trailer and independently swingable to the ceiling for easy movement to a loading position. Each partition is evenly supported by a pair of rails for easy movement without undue loading of the components. One rail extends along the sidewall and another along the center of the trailer for each partition. All of the rails are part of a framework that is supported solely by the sidewalls, i.e., with no loads placed on the ceiling. As a result, the system can be used in nearly all refrigerated trailers in use today. 
   A lift assembly in accordance with one embodiment of the invention includes a lift rope or other flaccid line, a pair of pulleys and a grip for holding the lift rope. A first pulley is generally aligned with the center of the partition. A second pulley guides the lift rope to a sidewall where it is less disruptive to the loading and unloading of goods. A grip for securing the lift rope is proximate the ceiling and avoids the formation of a taut rope segment along the sidewall. The grip has a simple construction that reliably holds the partition in the loading position as needed. In the preferred construction, the rails and lift assembly are each fully supported by the sidewalls without loading of the ceiling. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  shows a partition system in accordance with the present invention with two partitions in a side-by-side abutting relation to subdivide the refrigerated chamber. 
       FIGS. 2 and 3  are partial views of the framework of the system. 
       FIG. 4  shows the interconnection of the partitions to the trolleys and the trolleys to the center rails in the operative positions of the partitions. 
       FIG. 5  shows a first pulley of the system. 
       FIG. 6  shows a second pulley and grip of the system. 
       FIG. 7  shows connection of the lift assembly to one of the partitions. 
       FIG. 8  shows lifting of one of the partitions by the lift assembly. 
       FIG. 9  is a top schematic view showing the system in the chamber. 
       FIG. 10  is a top schematic view showing the system in an alternative arrangement in the chamber. 
       FIG. 11  is a partial, exploded view of a partition mount. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   A partition system  10  in accordance with the present invention subdivides a refrigerated chamber ( FIGS. 1–10 ). The chamber may be the interior of a truck trailer, railcar, cargo container or other similar structure. While the invention is further described in connection with a truck trailer for ease of illustration, it is not limited to such use. 
   Partition system  10  preferably includes a plurality of partial-width partitions  12  that can be arranged to subdivide interior chamber  14  of truck trailer  16  ( FIGS. 1 ,  4  and  9 – 10 ). In a preferred embodiment, the partitions each extend laterally across half the width of the chamber. Two partitions  12 , then, can be placed in abutting relation to close the entire chamber and subdivide the chamber into two different partitioned areas or zones  18 . Nevertheless, three or more partitions can be fit in side-by-side abutment across the width of the chamber in wide chambers. Each partition preferably has an identical construction, though there could be differences if desired. Further, each partition is also preferably insulated to better keep the chamber portions at the different desired temperatures. 
   Partition system  10  includes rails  20  to facilitate longitudinal movement of the partitions ( FIGS. 1–4  and  6 – 8 ). Side rails  20   a  extend along sidewalls  22  of trailer  16  proximal to ceiling  24 , and preferably are attached to the sidewalls via spaced brackets  25  secured by screws, rivets or the like. Cross bars  26  span the width of chamber  14  and also preferably attach to brackets  25 , but could attach to side rails  20   a . The number of cross bars to be used depends largely on the length of the chamber, the number of partitions used in the chamber, and/or the weight to be supported. In one preferred construction, three cross bars are provided—one adjacent front wall  27 , one adjacent rear doors  29 , and one centrally located. Center rails  20   b  are secured to the cross bars along the centerline of trailer  16  preferably by connectors  31 . Rails  20  and cross bars  26  form a framework  28  that lies adjacent ceiling  24  and out of the way for loading and unloading of the trailer. Seal members  33   a ,  33   b  are preferably provided between rails  20   a ,  20   b  and ceiling  24  to better insulate one chamber portion  18  from another. Further, the entire framework is attached to and supported by the sidewalls  22 , preferably through brackets  25 , but could be attached to the sidewalls in other ways. For example, side rails  20   a  and cross bars  26  could be directly fixed to sidewalls  22  or framework  28  could be secured to sidewalls  22  through the use of various other components or supports. Framework  28  forms the base of partition system  10  and supports the remaining components. As a result, all of the weight of system  10  is supported by sidewalls  22 , which is made to support loads in virtually all refrigerated truck trailers, without any loading of ceiling  24 . Partition system  10  is therefore usable in nearly every refrigerated truck trailer irrespective of whether the ceiling is of the load-bearing kind. 
   Rails  20  each preferably have a generally U-shaped configuration with side portions  30 , top portion  32  interconnecting side portions  30 , and bottom lips  34  extending inwardly from side portions  30 . Lips  34  extend only partially between side portions  30  so as to define a central slot  36 . Nevertheless, rails  20  could have other shapes so long as they movably support partitions  12 . Rails  20   a ,  20   b  also preferably have the same construction for ease and economics of manufacture, though different rail shapes could be used for the side and center rails. Further, the two center rails may be formed as a single integral member (not shown). 
   Trolleys  50  are movably supported on rails  20  and, in turn, support partitions  12  ( FIG. 4 ). In one preferred construction, trolleys include a narrow body  52  that extends through slot  36  in rails  20 . Rollers (not shown) are rotatably secured to the upper end of body  52  to ride along lips  34 , though skids or other arrangements could be provided to facilitate movement of the trolley along rail  20 . Screws  53  or other stops are provided in the ends of rails  20   a ,  20   b  to prevent inadvertent disconnection between trolleys  50  and rails  20   a ,  20   b  ( FIG. 3 ). An opening  56  is defined in a lower end of body  52  for receiving a pin  57  (e.g., one foot in length) that fits within hollow rod  58  ( FIGS. 1 and 4 ). In a preferred construction, pins  57  include flats  59  that cooperate with flats  61  in opening  56  ( FIG. 11 ). These flats provide increased support for holding pins  57  and the weight of partition  12 . Cotter pins  60  or the like are passed through pins  57  to hold them to trolleys  50 . If the partitions are struck by a fork lift truck, pallet or other structure, there is sufficient clearance for pins  57  to move. Specifically, pins  57  are forced to pivot along generally a horizontal plane about opening  56 , for example up to about 45°, toward the front of the trailer. This movement of pins  57  permits rod  58  to slide from one or both pins  57  and be separated from trolley(s)  50  to avoid damage to the partition. The partition can then be manually fit again onto the pins. Other releasable mounts could also be used. 
   Hinge plates  62  are rotatably mounted on each rod  58  for supporting partitions  12 . Each hinge plate  62  has a main plate portion  62   a  bolted or otherwise secured to partition  12  and an eye  62   b  that defines an aperture through which rod  58  is passed. In this way, partition  12  is freely rotatable about rod  58 . Of course, other trolley and hinge constructions could be used. 
   Each partition  12  preferably includes one or more handles  66  to facilitate their movement. In use, partitions  12  are pushed and/or pulled through chamber  14  by manually grasping one or more of the handles and causing the trolleys  50  to move along rails  20 . For each partition, one trolley is supported by one side rail  20   a  and one other trolley is supported by one center rail  20   b . This provides an even support for the partition, which makes for an easy and smooth longitudinal movement of the partition. Handles  66  may also grasped to pivot partition  12  about rod  58  to and from its loading position. The partition may be manually lifted and latched in a loading position against or close to framework  28  or swung about rod  58  by a lift assembly  67 . In the loading position, chamber  14  can be loaded or unloaded without interference from partitions  12 . Of course, the partitions could have a variety of different constructions, including with or without handles, straps, or specific seal members. 
   To subdivide chamber  14 , two partitions are preferably placed in side-by-side abutment in the operative position ( FIGS. 1 ,  4  and  9 – 10 ). Each partition preferably has a peripheral seal  70  to contact one sidewall  22 , ceiling  24 , an adjacent partition  12 , and floor  74  to block the passage of air from one portion to the next. Seal  70  is preferably sufficiently compressible to provide clearance for rails  20  without jeopardizing the seal needed to adequately subdivide the refrigerated chamber into portions capable of sustaining two different temperatures. Alternatively, the partitions could be shaped to accommodate the rails. Partitions  12  also preferably include straps  72  by which the adjacent partitions may be strapped together to form a more secure fit across the chamber. 
   Partition system  10  further preferably includes a lift assembly  67  for swinging each partition  12  from the operative position to the loading position, and vice versa ( FIGS. 5–8 ); although, a direct lifting and latching of the partitions by the operator without a lift assembly could be done. In the preferred construction, each lift assembly  67  includes a rope  82  or other flaccid member that includes a latch component  84  at the proximal end  86 . Latch  84  secures to ring  88  or other lock element fixed to partition  12  when the partition is to be lifted by lift assembly  80 . Ring  88  is preferably provided on one side of partition  12 , i.e., the lower side when stowed, though it could be provided on the other side or both sides of the partition. 
   A first or lifting pulley  90  is attached to one cross bar  26 , preferably the cross bar closest to rear doors  29 , approximately over the location of ring  88  on partitions  12  (i.e., roughly the center of the partition). Another first lifting pulley could be provided on other cross bars if more than one pair of partitions is included in the trailer. The first pulley is preferably located centrally of the partition. The first pulley is preferably mounted on a U-shaped base  89  to enable the pulley to freely orient itself as needed to connect to and lift the partition. A locking or second pulley  92  is also attached to the same cross bar  26  near side rail  20   a  to a position out of the way of the goods. Second pulley  92  includes a grip or tackle  94  (e.g., as commonly used in sailing) that automatically holds the rope from moving in the release direction. Grip  94  is preferably integral with second pulley  92  but could be a separate member if desired. Grip  94  includes a pair of spring-biased, eccentric jaws  96 , preferably with serrations  98 , which are normally biased toward the closed position. In use, rope  82  passes around first pulley  90 , to and around second pulley  92 , and through jaws  96  of grip  94 . The jaws are pushed outward to an open position for passage of the rope. The jaws are biased toward the closed position to press against the rope. The jaws securely hold the rope in place and prevent slippage or release of the partition from the loading position. To release the partition to the operative position, rope  82  is pulled transversely out of grip  94  and the rope permitted to freely slide back over pulleys  90 ,  92  under the weight of partition  12 . A stop, preferably in the form of a generally U-shaped bar, is set across from jaws  96  to prevent pulling the rope from pulley  92 . With the partition lowered, hook  84  is released from ring  88 . Partition  12  can then be moved longitudinally along rails  20  to the desired position. 
   In one embodiment, one or more partitions are mounted on each pair of rails  20   a ,  20   b  to subdivide chamber  14  into two or more chamber portions, e.g., chamber portions  18   a ,  18   b  ( FIGS. 1 and 9 ). In an alternative construction, a longitudinal partition or bulkhead  103  can be mounted along the centerline of the bulkhead to subdivide the bulkhead longitudinally as well as laterally to form multiple chamber portions, e.g., chamber portions  18   c ,  18   d ,  18   e  ( FIG. 10 ). While longitudinal partitions  103  are preferably of conventional design and held in place by friction, they could be fabricated for suspension from framework  28 . Longitudinal partitions  103 ′ can also be used with partitions  12  to form a z-shaped partition border, which can be useful when an odd number of pallets are loaded into the refrigerated chamber. 
   The above discussion concerns the preferred embodiments of the present invention. Various other embodiments as well as many changes and alterations may be made without departing from the spirit and broader aspects of the invention as claimed. For example, the use of a framework of rails and cross members supported solely by the sidewalls of the chamber could be used with other partition systems. Also, the lift assembly and the use of mounts that permit release of the partitions when struck could be effectively used with many different partition systems, including those with single axles or full width partitions.

Technology Classification (CPC): 1