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This application claims the benefit of U.S. Provisional Application No. 60/157,445, filed Oct. 4, 1999. 
    
    
     FIELD OF INVENTION 
     The subject invention generally relates to a step assembly for access to a truck box or truck bed of a pick-up truck having a tailgate. More specifically, the invention relates to a tailgate step assembly for accessing the truck box or bed of the pick-up truck through the tailgate. 
     BACKGROUND OF INVENTION 
     Pick up trucks usually include a tailgate which is normally about 30 inches above the ground when the tailgate is in the open horizontal position. The elevated level of the tailgate makes entry and exit into and out of the truck box difficult for most people. Thus there have been many proposals for providing easier access to the truck bed in the form of folding steps. Examples of such steps include: U.S. Pat. Nos. 4,191,388; 4,846,487; 4,848,821; 5,028,063; 5,205,603; 5,342,073; 5,687,813; 5,732,996; and 5,944,332. 
     The prior art folding steps provide a step which can be folded from a stowed position to a deployed position presenting a step enabling access to the pick up truck bed. However, such steps are not packaged in a manner which hides the step when in the stowed condition or will present a tripping hazard when the tailgate is opened and the step kept in the stowed condition. 
     SUMMARY OF INVENTION 
     The disadvantages of the prior art may be overcome by providing a stowable step which slides into and out of a housing enabling the step to be stowed and deployed. 
     It is desirable to provide a housing having a low profile to minimize any intrusion of the stowable step into the cargo volume of the pick up truck cargo bed. 
     According to one aspect of the invention, there is provided a stowable step having a housing, a U-shaped step platform and a sliding member pivotally engaging the step platform. The sliding member is slidably mounted within the housing for reciprocating movement between a retracted stowed position wherein the platform extends into the housing and a deployed position wherein the platform can pivot relative to the sliding member to a substantially vertical position. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Advantages of the present invention will be readily appreciated as the same becomes understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein: 
     FIG. 1 is a perspective view of a step assembly of the present invention in an extended position; 
     FIG. 2 is a perspective view illustrating the step assembly of FIG. 1 in the stowed position; 
     FIG. 3 is a top view of the step assembly, with cover removed, in the stored position; and 
     FIG. 4 is a side view of the step assembly in the extended position. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The subject invention generally relates to a step assembly shown at  10  for providing access into a truck box or a truck bed  14  of a pick-up truck  16 . The step assembly  10  will be described further hereinbelow in terms of the pick-up truck  16  and the tailgate step assembly  10 . However, as appreciated, the step assembly  10  may be utilized for access into vehicles other than the pick-up truck  16 . 
     The tailgate step assembly  10  includes a housing  18  having a bottom panel  20  and a cover  28 . The bottom panel  20  is mounted to an inside surface  22  of a tailgate  24  of the pick-up truck  16 . A plurality of screws  26  spaced about the outer periphery  12  of the housing  18  extend into the tailgate  24  of the pick-up truck  16  to mount the step assembly  10  thereon. 
     The housing  18  is manufactured from a generally durable material that is resistant to the ‘wear and tear’ typically associated with use of the pick-up truck  16 . Cover  28  is contoured to hide the inner components of tailgate step assembly  10  within the housing  18 , and to protect the tailgate step assembly  10  from damage due to movement of heavy cargo that may be stored within the truck bed  14  of the pick-up truck  16 . Cover  28  is contoured to define slide channels  27 ,  29 . The trailing edge of cover  28  has an flange presenting a stop  54 . 
     Referring specifically to FIG. 3, the tailgate step assembly  10  further includes a U-shaped internal sliding member  30  disposed within the housing  18 , and a U-shaped step  32 . The sliding member  30  and the step  32  are slidably mounted within the housing  18 . 
     The sliding member  30  includes first  34  and second  36  legs extending from ends of a bight portion  35 . Bight portion  35  has a profile which is preferably less than the profile of legs  34 ,  36 . Legs  34 ,  36  are slidably received by channels  27 ,  29 . 
     The step  32  includes first  38  and second  40  legs extending from ends of a bight portion  51  which forms a foundation for platform  52 . As shown best in FIG. 1, the first  38  and second  40  legs are preferably tubular and are slidingly received within channels  27 ,  29 . The first  38  and second  40  legs may be of any shape. Also, the first  38  and second  40  legs are preferably constructed of materials resistant to environmental degradation. 
     First  46  and second  48  hinges are disposed between the first legs  34 ,  38  and second legs  36 ,  40 . The first  46  and second  48  hinges permit the step  32  to extend vertically downward when the first  46  and second  48  hinges are positioned at an outer edge  50  of the tailgate  24  (see specifically FIG.  4 ). 
     At least one of the hinges  46 ,  48  is preferably designed to limit rotational movement of the step  32  to about 90° from the plane of the sliding movement of sliding member  30 . 
     The tailgate step assembly  10  optionally includes a step platform  52  extending transversely between the first  38  and second  40  legs. The step platform  52  may be integral to the first  38  and second  40  legs. Optionally, the step platform  52  could be welded the first  38  and second  40  legs thereby establishing a single unitary device. 
     The step platform  52  is constructed of material suitable to withstand the forces present when the operator  44  is stepping into the truck bed  14  of the pick-up truck  16 . Optionally, a traction surface  56  may be disposed on step platform  52 . As appreciated, the traction surface enables safe operation of the tailgate step assembly  10  at all times including operation under adverse conditions such as rain or snow. 
     Sliding member  30  slides within the housing  18  between a stowed position wherein the bight portion  35  abuts against the cover  28  and a deployed position wherein the bight portion abuts against the stop  54  of cover  28 . 
     In the stowed position, the tailgate step assembly  10  is substantially disposed within the housing  18  (best shown in FIG.  3 ). As a result, the tailgate step assembly  10  has a relatively low profile. Additionally, this low profile of the tailgate step assembly  10  contributes to an overall aesthetically pleasing appearance for the truck bed  14  of the pick-up truck  16 . When in the stowed position, the tailgate  24  of the pick-up truck  16  is also typically in a stored position and the tailgate step assembly  10 , including the housing  18 , is not perceivable by persons positioned behind the pick-up truck  16 . 
     To manipulate the assembly  10  into the open or deployed position, the operator  44 , standing outside the truck bed  14 , pulls the tailgate step assembly  10  by handling the step platform  52  and pulling the step platform  52  outwardly. As a result, the sliding member  30  of the tailgate step assembly  10  slides within the inner channels  27 ,  29  of the housing  18  toward the outer edge  50  of the tailgate  24 . Correspondingly, the first  34  and second  36  legs and the first  46  and second  48  hinges slide within the inner channels of the housing  18  and extend toward the outer edge  50  of the tailgate  24 . As a result, when the pivot point of the first  46  and second  48  hinges extend horizontally beyond the outer edge  50  of the tailgate  24 , the first  38  and second  40  legs and the step platform  52  are able to swing downwardly to the deployed or extended position. The step platform  52  is now accessible to the operator  44  for stepping into the truck bed  14  of the pick-up truck  16 . Preferably, the first  38  and second  40  legs swing to a position substantially perpendicular to the housing  18 . As appreciated, the dimensions of the first  38  and second  40  legs are preferably such that the step platform  52  is in a safe and comfortable position for the operator  44  to step into the truck bed  14 . 
     In order to return the assembly  10  to the closed or stored position, the operator  44  rotates the step platform  52  upwardly such that the first  38  and second  40  legs are now generally horizontal to the inside surface  22  of the tailgate  24  of the pick-up truck  16 . If desired, the operator  44  can return the tailgate step assembly  10  to its closed position by pushing the step platform  52  such that the first  38  and second  40  legs align with the inner channels of the housing  18  and slide the legs  38 ,  40  inwardly. At this point, the operator  44  can also return the tailgate  24  to a closed position thereby containing the tailgate step assembly  10  within the truck bed  14  of the pick-up truck  16 . Alternatively, the operator  44  may leave the tailgate  24  in an extended position while maintaining the assembly  10  in the closed position (as shown in FIG.  3 ). If the tailgate  24  remains in the extended position, the low profile of the housing  18  of the tailgate step assembly  10  maintains the overall aesthetic appearance of the pick-up truck  16 . 
     The invention has been described in an illustrative manner, and it is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than of limitation. Many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that the invention may be practiced otherwise as specifically described.

Summary:
A stowable step has a housing, a U-shaped step platform and a sliding member pivotally engaging the step platform. The sliding member is slidably mounted within the housing for reciprocating movement between a retracted stowed position wherein the platform extends into the housing and a deployed position wherein the platform can pivot relative to the sliding member to a substantially vertical position.