Abstract:
A method and apparatus are disclosed for locking at least two safety retainers together. Each safety retainer has a pallet-attached base and a ramp-attached mating bracket. Each safety retainer includes a base and a bracket. Each bracket is coupled to a ramp that is can be removably attached to a pallet. Each base includes a retaining arm for locking the base to the bracket when the ramp is coupled to the pallet. A locking mechanism is capable of being temporarily coupled to a first retaining arm in a first safety retainer and a second retaining arm in a second safety retainer for locking the retaining arms together. The first and second retaining arms must operate as a single unit, and cannot be moved independently, when the locking mechanism is coupled to the first and second retaining arms. The first and second retaining arms operate independently as separate units when the locking mechanism is not coupled to the first and second retaining arms.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates in general to the field of shipment packaging, and in particular to pallets. Still more particularly, the present invention relates to a locking member for locking at least two safety retainers together so that the safety retainers function as a single unit, where each safety retainer prevents an object from being unloaded from a pallet unless the pallet ramp to which the safety retainer is attached is properly positioned with and secured to the pallet. 
   2. Description of the Related Art 
   Large and heavy products, such as computer servers, are typically shipped to a customer on a pallet. Upon delivery, the shipment must be manually offloaded from the pallet. To prevent damage from being jarred by dropping the shipment off the edge of the pallet, which is typically several inches high, the shipment is slid off the pallet using a ramp. Consider, for example, the arrangement shown in  FIG. 1A . A shipment  102  is shipped to a customer&#39;s site on a pallet  104 , which is set on the ground  106 . To avoid jarring damage that could result from simply sliding the shipment  102  off the right side of the pallet  104 , a ramp  108  is secured by a latch  110  to the pallet  104 , providing a slide on which the shipment  102  can be moved to the ground  106 . 
   The system shown in  FIG. 1A  works safely as long as latch  110  securely attaches ramp  108  to pallet  104 . However, if ramp  108  and pallet  104  are not properly aligned, latch  110  is not being properly aligned. The result is shown in  FIG. 1B , which depicts the end result of ramp  108  falling to the ground  106  while supporting the load of shipment  102 . Shipment  102  has thus fallen to the ground  106  from a distance that is the height of pallet  104 . If shipment  102  is a fragile product, such as a populated computer server chassis, the fall will likely cause expensive, if not irreparable, damage to shipment  102 . 
   BRIEF SUMMARY OF THE INVENTION 
   The method and apparatus of the illustrative embodiment of the present invention uses a locking mechanism to lock at least two safety retainers together so that the safety retainers operate together as one single unit. Each safety retainer has a pallet-attached base and a ramp-attached mating bracket. A first safety retainer includes a first base and a first bracket. The first bracket is coupled to a first ramp that can be removably attached to a pallet. The first base includes a first retaining arm for locking the first base to the first bracket when the first ramp is coupled to the pallet. A second safety retainer includes a second base and a second bracket. The second bracket is coupled to a second ramp that can be removably attached to the pallet. The second base includes a second retaining arm for locking the second base to the second bracket when the second ramp is coupled to the pallet. The locking mechanism is capable of being temporarily coupled to the first and retaining arms for locking the retaining arms together. The first and second retaining arms operate as a single unit during movement of the retaining arms when the locking mechanism is coupled to the first and second retaining arms. 
   The above, as well as additional purposes, features, and advantages of the present invention will become apparent in the following detailed written description. 

   
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further purposes and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, where: 
       FIGS. 1A-1B  depict a prior art pallet and ramp system that is susceptible to latching failure due to misalignment of the pallet and ramp; 
       FIG. 2  illustrates a pallet and multiple ramp configuration as used in accordance with an illustrative embodiment of the present invention; 
       FIG. 3A  depicts the inventive latching system before a base and mating bracket are mated in accordance with an illustrative embodiment of the present invention; 
       FIG. 3B  illustrates additional detail of the mating bracket in accordance with an illustrative embodiment of the present invention; 
       FIG. 3C  depicts the latching system shown in  FIG. 3A  in a mated position in accordance with an illustrative embodiment of the present invention; 
       FIG. 4A  illustrates, using two oblique views, additional detail of the base in which a retainer arm on a first rod is in a locked upright position by a second rod, thus preventing a shipment on the pallet from moving past the retaining arm in accordance with an illustrative embodiment of the present invention; 
       FIG. 4B  depicts, using two oblique views, the base with the second rod moved laterally away from the retaining arm, such that the second rod no longer prevents the retaining arm from folding down in accordance with an illustrative embodiment of the present invention; 
       FIG. 4C  illustrates, using two oblique and one side view of the base, the retaining arm in the base as being unrestricted by a chamfer that has been moved out of a restrictor slot in accordance with an illustrative embodiment of the present invention; 
       FIG. 4D  depicts, using two oblique and one side view of the base, the retaining arm in a folded down unrestricting position, such as shown in  FIG. 3   c  in accordance with an illustrative embodiment of the present invention; 
       FIG. 5  is a perspective view of a locking member in accordance with the illustrative embodiment of the present invention; 
       FIG. 6  is top view of a locking member in accordance with the illustrative embodiment of the present invention; 
       FIG. 7  is a front view of a locking member in accordance with the illustrative embodiment of the present invention; 
       FIG. 8  is a side view of a locking member in accordance with the illustrative embodiment of the present invention; and 
       FIG. 9  is a front view of a locking member coupled to two retaining arms in accordance with the illustrative embodiment of the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   With reference now to  FIG. 2 , a top view of a pallet  202  is shown having beveled edges  204   a - b  at each end of pallet  202 . Four ramps  206   a - d  are attached to respective beveled edges  204   a - b  using latching systems  208   a - d . Thus, the ramps  206   a - d  reach the ground  302  as shown below in the partial side view of pallet  202  depicted in  FIG. 3C . 
   Referring now to  FIG. 3A , a side view of pallet  202  and ramp  206   b  (which is representative of each of the ramps  206   a - d ) shows additional detail of latching system  208   b . Latching system  208   b , also called a safety retainer, which is representative of each of the latching systems  208   a - d  shown in  FIG. 2 , includes a base  304  and a mating bracket  306 . 
   Base  304  includes a base bracket  308 , which has a first base plate  310  that is directly attached to the upper surface of beveled edge  204   a . Base  304  also has a first rod  312 , a retainer arm  314 , and a second rod  316 , whose function is described in further detail below. Although first rod  312  and second rod  316  are depicted as cylindrical rods, it should be understood that their shape is not limited to cylindrical rods, but rather any rod having a geometry that permits first rod  312  to rotate as described below. 
   Mating bracket  306  has a second base plate  318  that is directly attached to the lower surface of ramp  206   b . As shown in greater detail in  FIG. 3B , mating bracket has a first slot plate  320   a  and a second slot plate  320   b  attached to second base plate  318 . Each slot plate  320  has a first slot  322  and a second slot  324 . As shown in  FIG. 3C , first slot  322  has a first throat width  326 , and second slot  324  has a second throat width  328 . While first throat width  326  and second throat width  328  may be the same size or different sizes, first throat width  326  is wide enough to allow first slots  322  to mate with first rod  312 , and second throat width  328  is wide enough to allow second slots  324  to mate with only a thin portion (discussed below) of second rod  316 . 
   As shown in  FIG. 3C , and as described in greater detail below, when second rod  316  is laterally slid within base  304  as described below, it no longer is able to block the rotation of retainer arm  314 , which is thus able to fold downward, allowing a shipped object  330  on top of the pallet  202  to slide down ramps  206   a - b  shown in  FIG. 2 . 
   With reference now to  FIG. 4A , additional detail is shown for base  304 . For clarity&#39;s sake, pallet  202 &#39;s beveled edge  204 , to which base  304  is attached is not shown, nor is ramp  206  or its mating bracket  306 . Mating bracket  306  and base  304  together make up latching system  208 . 
   Base bracket  308  has a first side plate  402  and a second side plate  404  that extend away, preferably perpendicularly, from first base plate  310 . A first end of first rod  312  extends through a first hole  406 , and the second end of first rod  312 , to which retainer arm  314  is attached, extends through a second hole  408 . To keep first rod  312  from sliding past first hole  406 , a first rod travel limiter  410  is part of the first end of first rod  312 . First rod travel limiter  410  may be a collar as depicted, or may be any protrusion or projection of or from first rod  312  that limits the lateral movement of first rod  312  past first hole  406 . Adequate space is provided between first rod travel limiter  410  and the exterior face of first side plate  402  to permit first rod  312  to move laterally to allow a retainer arm restrictor  412  to move clear of a restrictor slot  414 , as shown below in  FIG. 4C . Preferably, a first rod force lock  416 , which is preferably a spring as shown, keeps retainer arm restrictor  412  within restrictor slot  414  by providing a force between first rod travel limiter  410  and the exterior face of first side plate  402 . Alternatively, first rod force lock  416  may be a system of magnets, bands, other springs, or any other means for providing a lateral force to keep retainer arm restrictor  412  within restrictor slot  414 , thus preventing first rod  312  from rotating and thus preventing retainer arm  314  from folding down. 
   Second rod  316  has a thick rod portion  418  and a thin rod portion  420 . Thin rod portion  420  has a diameter that is small enough to mate with the second slots  324  of mating bracket  306 , while thick rod portion  418  is too thick to pass through the second throat width  328  to mate with second slots  324  (all shown in  FIGS. 3B-3C ). The only way for mating bracket  306 , including second slots  324 , to mate with base  304  is to slide second rod  316  in the direction of knob  422 , thus moving the thick rod portion  418  out of the way, allowing the thin rod portion  420  to mate into the second slots  324 . Knob  422  serves as a convenient hold to pull second rod  316  to the side. In addition, in a preferred embodiment knob  422  is magnetized, thus keeping knob  422  against first side plate  402  until the ramp  206  (with its mating bracket  306 ) is properly aligned with base  304 , and second rod  316  can be pulled to the side as described herein. Alternatively, any system of springs, counterweights, or other means for temporarily keeping knob  422  positioned against first side plate  402  may be used. 
   Thick rod portion  418  slides through a thick third hole  424  in first side plate  402 , while thin rod portion  420  slides through a thinner fourth hole  426  in second side plate  404 . Second rod  316  is aligned to slide into fourth hole  426  by an alignment bracket  428  having a fifth hole  430 , preferably for aligning the thin rod portion  420  as shown. 
     FIG. 4A  thus depicts base  304  in a double-locked position, in which retainer arm  314  is prevented from folding down by both retainer arm restrictor  412  as well as by second rod  316  protruding past second side plate  404 . Referring now to  FIG. 4B , base  304  is depicted with second rod  316  having been pulled to one side such that the thick rod portion  418  is no longer between first side plate  402  and second side plate  404 . In this position, mating bracket  306  (not shown) is able to mate its second slots  324  with thin rod portion  420  and its first slots  322  with first rod  312 . By feeling this mating between mating bracket  306  and base  304  during the manual positioning of the ramp  206 , the user is assured that ramp  206  is properly aligned with pallet  202  and its base  304 . Second rod  316  is no longer outside second side plate  404 , and thus second rod  316  no longer poses an impediment to a downward travel of retainer arm  314 . 
   With reference now to  FIG. 4C , assume that ramp  206  and mating bracket  306  (neither shown) are properly mated with base  304 . First rod  312  is then pushed to the side until first rod travel limiter  410  hits against the first side plate  402 , freeing retainer arm restrictor  412  from restrictor slot  414 . First rod  312  is now free to rotate, allowing retainer arm  314  to fold downward, as shown in  FIG. 4D  and  FIG. 3C . Since retainer arm  314  is no longer sticking upwards, object  330  is now free to slide towards and down ramp  206 . 
     FIG. 5  is a perspective view of a locking member  500  in accordance with the illustrative embodiment of the present invention.  FIG. 6  is top view of a locking member in accordance with the illustrative embodiment of the present invention.  FIG. 7  is a front view of a locking member in accordance with the illustrative embodiment of the present invention.  FIG. 8  is a right side view of a locking member in accordance with the illustrative embodiment of the present invention. 
   In the illustrative embodiment, locking member  500  is rectangular although any other suitable shape can be used. Locking member  500  includes a first opening  502  through a first end  504  of locking member  500  and a second opening  506  through a second end  508  of locking member  500 . First opening  502  is for receiving a retaining arm  314   a  of a first base  304   a . Second opening  506  is for receiving a retaining arm  314   b  of a second base  304   b . Locking member  500  includes an opening  510  in an end surface  512 . Locking member  500  may also include another opening (not shown) in an opposite end surface. First opening  502  goes completely through locking member  500  from a top  514  through a bottom  516  of locking member  500 . Second opening  506  goes completely through locking member  500  from a top  514  through a bottom  516  of locking member  500 . Locking member  500  includes a front  520 . 
   A safety release, such as a button, may be provided utilizing opening  510  such that locking member  500  snaps into place when received by two retaining arms and cannot be removed from the retaining arms until the button is depressed through opening  510 . 
     FIG. 9  is a front view of a locking member coupled to two retaining arms in accordance with the illustrative embodiment of the present invention. Locking member  500  is utilized to temporarily couple arm  314   a  and arm  314   b  so that arms  314   a ,  314   b  cannot be actuated separately. In this manner, arms  314   a  and  314   b  cannot be moved separately. Arms  314   a  and  314   b  move together as one unit when locking member  500  is lowered over arms  314   a  and  314   b  as depicted in  FIG. 9 . 
   As described above, a safety retainer includes a base and a bracket. The bracket is coupled to a ramp that is removably attached to a pallet. The base includes a retaining arm for locking the base to the bracket when the ramp is removably coupled to the pallet. The illustrative embodiment is a locking member for locking retaining arm  314   a  of a first safety retainer to retaining arm  314   b  of a second safety retainer. Locking member  500  is capable of being temporarily coupled to both retaining arms  314   a ,  314   b  for locking retaining arms  314   a ,  314   b  together to prevent either arm  314   a  or arm  314   b  from being able to be moved separately from the other retaining arm. When locking member  500  is lowered over arms  314   a  and  314   b , both ramps, i.e. the ramps that are attached to the safety retainers that include arms  314   a  and  314   b , must be properly installed on the pallet before retainer arms  314   a  and  314   b  can be moved. 
   An additional brace, such as brace  900   a  and/or brace  900   b , may be utilized to further support and protect packages or server racks that are installed on the pallet. Brace  900   a  slides over a top  902   a  of arm  314   a . Brace  900   b  slides over a top  902   b  of arm  314   b . Brace  900   a ,  900   b  provides a surface area  904  that is larger than surface area  906  of the retaining arm. The larger surface area provides additional support to the products on pallet  202 . The braces are for stabilizing products that rest on the pallet. 
   The present invention is thus a great safety improvement. Shipped objects are not able to be slid off a pallet until both ramps have been properly installed on the pallet, and the retainer arms, locked together using the locking member, are folded down. The retaining arms, locked together using the locking member, can be folded down only when the ramps, to which the retaining arms are coupled, are properly secured to the pallet. 
   The illustrative embodiment solves a safety issue found in the prior art and provides a safe and reliable way to remove both empty and configured server racks from their shipping pallets. The illustrative embodiment will not allow the rack to be removed unless both ramps have been properly installed on the pallet. 
   While the invention has been particularly shown and described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention.