Retractable wheel assembly
BACKGROUND OF THE INVENTION 
     1. Technical Field 
     This invention relates to a retractable wheel assembly for an article of luggage, such as a suitcase. 
     2. Background 
     Some suitcases have conventional rollers or wheels that are fixed in their exposed and operative positions which subject the wheels to damage after the suitcases are checked-in by an airline passenger and returned to the passenger at his or her destination, as attested to by the number of damage claims to which the airlines are subjected for damage to the luggage, in general, and damage to the rollers and wheels, in particular. 
     SUMMARY OF THE INVENTION 
     Accordingly, the object of the invention is to contribute to the solution of the discussed problem of the art by providing a retractable wheel assembly that can simply be moved manually by a passenger, at check-in, from an extended operative position to its retracted position in which none of the wheels are exposed and subject to damage; and, when reaching his destination, such passenger, at baggage pick-up, can simply manually move the retractable wheel assemblies to their extended operative positions to expose the wheels for purposes of &#34;wheel-barrowing&#34; or &#34;trolleying&#34; movement of the suitcase. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     This object and other objects of the invention should be discerned and appreciated from the detailed description of the preferred embodiment taken in conjunction with the drawing figures, wherein like reference numerals refer to similar parts throughout the several views, in which: 
     FIG. 1 is a perspective view of the invention; 
     FIG. 2 is a side-elevational view, partly in section; 
     FIG. 3 is a perspective view of the wheel assembly; 
     FIG. 4 is a rear-elevational view, partly in section; 
     FIG. 5 is a perspective view, showing a modification of the wheel assembly structure of FIG. 3; 
     FIG. 6 is a side-elevational view showing a suitcase, with its front and rear wheels in their extended operative positions, preparatory to and for use in effecting &#34;trolleying&#34; movement of the suitcase; and 
     FIG. 7 is a side-elevational view showing a suitcase, with its rear wheels in their extended operative positions, preparatory to and for use in effecting &#34;wheel-barrowing&#34; movement of the suitcase. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In FIG. 1 of the drawings, reference numeral 1 generally refers to the invention showing a suitcase having two halves, a right half 3 and a left half 5, hinged together at their bottoms by a hinge 7 (shown in FIG. 4). The suitcase has four corners, right-side front and rear corners 9 and 11 (sown in FIG. 2) and left-side front and rear corners 13 and 15. The halves 3 and 5 are securable together at their tops by conventional means, not shown, such as by clasps or locks. The suitcase has a grip handle 17. As shown in FIG. 1, the suitcase has a draw strap 19; as shown in FIG. 6, a collapsible draw bar 21; and as shown in FIG. 7, a draw strap 23. The suitcase&#39;s bottom base is made of rigid plastic material and the four corners 9, 11, 13 and 15 each have inverted wells 25 of similar construction and configuration. In FIG. 7, the suitcase has only an inverted well in its right-side rear corner and an inverted well (not shown) in its left-side rear corner. Each of the inverted wells has and defines a closed top portion 27, front and rear opposite end walls 29 and 31, right-side and left-side opposite lateral walls 33 and 35, and an open bottom portion 37. 
     Each inverted well 25 houses a retractable wheel assembly 39, having a forward bifurcated bracket 41 whose base 43 is riveted to the closed top portion 27, as shown; and a rearward bifurcated bracket 45 whose base 47 is riveted to the rear-end wall 31, as shown. The forward bifurcated bracket 41 projects right-side and left-side opposed lateral sides 49 and 51 having mutually facing aligned detent recesses 53. The rearward bifurcated bracket 45 projects right-side and left-side opposed lateral sides 55 and 57 having mutually facing aligned detent recesses 59. 
     The right-side and left-side lateral walls 33 and 35 carry aligned bearings 61, adhesively affixed thereto, which pivotally mount a transverse pin 63 carrying one end 65 of an elongated arm 67 that has laterally projecting spring-biased detents 69, aligned by the elongated arm&#39;s angular pivotal moving relationship with either the forward aligned detent recesses 53 in the opposed lateral sides 49 and 51 of the forward bifurcated bracket 41, or with the rearward aligned detent recesses 59 in the opposed lateral sides 55 and 57 of the rearward bifurcated bracket 45. 
     The elongated arm 67 has an opposite end 71 carrying a transverse axle 73 freely mounting lateral wheels 75, retained thereon by spring clips 77. The elongated arm 67 has two positions of manipulatively pivotal angular movements between a first retracted position and a second extended operative position. A finger hold 79, formed and provided on the opposite end 71 of the elongated arm 67, facilitates its movements be-the two positions. In its first retracted position, shown in full lines in FIGS. 1, 2 and 3, and in broken lines in FIG. 4, the elongated arm&#39;s spring-biased detents 69 are engaged in manipulatively releasable locking engagements with the forward aligned detent recesses 53, and with the elongated arm 67 and its lateral wheels 75 being spatially above the inverted-well&#39;s open bottom portion 37 and within the inverted-well&#39;s interior. In its second extended operative position, shown in full lines in FIGS. 4, 6 and 7, and in broken lines in FIGS. 1, 2 and 3, the elongated arm&#39;s spring-biased detents 69 are engaged in manipulatively releasable locking engagements with the rearward aligned detent recesses 59, and with the lateral wheels 75 being below the inverted-well&#39; s open bottom portion 37 and touching a floor or ground surface. It should be noted that the expression &#34;manipulatively releasable locking engagement&#34; means that the elongated arm&#39;s spring-biased detents 69 can be disengaged from the aligned detent recesses by a human operator&#39;s simply disposing one of his fingers upon the finger hold 79 and appropriately pressing the finger hold 79 to pivot the elongated arm 67 sufficiently in the appropriate direction to free the spring-biased detents 69 from their locking engagements with their immediate detent recesses. 
     The wheels 75 in their second extended operative positions via their arms 67, are shown in FIG. 6 in full lines for &#34;trolleying&#34; movement of the suitcase, i.e., with all four sets of wheels touching the floor or ground surface. The wheels 75 in their second extended operative positions, via their arms 67, are shown in full lines in FIG. 7, and in broken lines in FIG. 2, for &#34;wheel-barrowing&#34; movement of the suitcase, i.e., with only the rear wheels touching the floor or ground surface. 
     The only structural difference between the retractable wheel assembly 39 and its modification, shown in FIG. 5, is that the separate forward and rearward bifurcated brackets 41 and 49 are united in one bifurcated bracket (generally referred to by reference numeral 18) riveted to both the closed top portion 27 and the rear-end wall 31. The forward aligned detent recesses 83 function the same as the forward detent recesses 53 and the rearward aligned detent recesses 85 function the same as the rearward detent recesses 59. 
     It should further be appreciated that the finger hold 79 facilitates the human operator&#39;s moving the arm 67 out of its first retracted position and into its second extended operative position, as well as out of the arm&#39;s second extended operative position and into its first retracted position, with the inside facing surfaces of the bracket&#39;s lateral sides camming and thereby compressing the arm&#39;s spring-biased detents to disengage and free such spring-biased detents from their locking engagements with their immediate detent recesses.