in referring to fig1 of the drawings , the concept of this invention or device 1 is readily disclosed . the device 1 includes , as depicted therein , a first plate 2 generally rectangular in shape and a second plate 4 that extends from the first plate 2 . the second plate 4 has a slightly narrower width than the first plate 2 . each plate has a turned down edge or lip 3 upon three or more perimeter sides . the first plate 2 has two longitudinal edges 2 a and one lateral edge 2 b perpendicular to the longitudinal edges 2 a . the second plate 4 also has two mutually parallel spaced apart longitudinal edges 4 a but two mutually parallel spaced apart lateral edges 4 b perpendicular to the longitudinal edges 4 a . the lips 3 reinforce the perimeter of the shelf 1 and increase rigidity of the shelf 1 when under load . upon the outer lips 3 of each plate , two or more pads 17 extend further outward to grasp the wall of a locker . the pads 17 have a generally round shape and secure into slots within the lip 3 . the slots open downward so the shelf 1 remains on the pads 17 when upright and under a load . in the preferred embodiment , each plate has an open pattern of holes 15 flanking the longitudinal axis . the holes 15 provide ventilation and allow the user to see through the shelf 1 if needed . centered between the holes 15 , each plate has a solid longitudinal strip or spine 16 that conceals a means to secure or securing mechanism 6 of the shelf 1 . flanking the spine 16 , the first plate 2 has two spaced apart and mutually parallel tracks 7 visible upon the top surface . the tracks 7 have a lengthwise slot 8 and run in the longitudinal direction of the shelf 1 . the securing mechanism appears in fig2 beneath the spine 16 of both plates . beneath the first plate 2 , the securing mechanism has a toothed rack 12 . the rack 12 extends longitudinally . the teeth 12 a are adjacent to a pattern of holes 15 upon one side of the spine 16 . corresponding to the teeth 12 a , a crank 13 beneath the second plate 4 secures the second plate 4 relative to the first plate 2 when turned . the crank 13 has a handle 13 d offset from a head 13 a later shown in fig5 . opposite from the head 13 a , the handle 13 d approaches a pair of stops 14 . the stops 14 are mutually spaced apart for a snug fit of the handle 13 d . when engaged , the stops 14 prevent the handle 13 d from rotating when the shelf 1 is secured . also beneath the first plate 2 , a gusset 7 a supports each track 7 upon which the second plate 4 slides . the tracks 7 serve as one component of a means for telescoping 5 the second plate 4 longitudinally from the first plate 2 . upon the other end of each track 7 , the first plate 2 has a glide 8 . the glides 8 are located at the lower edge of the lips 3 on the edges 2 a also parallel to the longitudinal direction of the shelf 1 . the glides 8 support the lips 3 on the longitudinal edges 4 a of the second plate 4 and form a load bearing connection of the second plate 4 to the first plate 2 at any width of the shelf . moving to the second plate 4 and opposite the pads 17 , gussets 7 a support the keys 10 extending above the second plate 4 collinear with the tracks 7 of the first plate 2 . the keys 10 of the second plate 4 appear more clearly in fig3 . upon the top surface of the second plate 4 , two depressed parallel grooves 11 run . opposite the pads 17 , each groove 11 has a key 10 . the key 10 has a generally t shaped cross section that engages the groove 11 upon the first plate 2 . the keys 10 and grooves 11 cooperate to extend the second plate 4 longitudinally from the first plate 2 while maintaining a structural connection between the plates . generally centered between the keys 10 , the head 13 a is located upon the spine 16 opposite the pads 17 . the head 13 a has a generally round flat shape with two or more teeth 13 b radially disposed upon the circumference of the head 13 a . in the preferred embodiment , the head 13 a has three teeth 13 b regularly spaced so the teeth 13 b permit partial rotation of the handle 13 d when engaging the rack 12 . the rotation of the crank 13 induces extension of the second plate 4 slightly from the first plate 2 for a friction fit . turning beneath the second plate 4 , fig4 shows the handle 13 d of the crank 13 . the handle 13 d has a tapered elongated shape with a grip 13 f upon one end . opposite the grip 13 f , a hole admits the stem 13 c of the head 13 a . with a lip adjacent to the stem 13 c , the crank 13 can rotate within 180 ° when moving the second plate 4 relative to the first plate 2 . proximate to the pads 17 and opposite of the keys 10 , gussets 11 a support the outer corners of the second plate 4 . the crank 13 appears alone in fig5 . as before , the head 13 a has a round flat shape with two or more teeth 13 b extending radially . via a stem 13 c through the second plate 4 , the head 13 a attaches to the handle 13 d . proximate to the head 13 a , the handle 13 d has a rounded end where the head 13 a and teeth 13 b fit within the shape of the handle 13 d . away from the head 13 a , the handle 13 d tapers in width as an elongate form . as shown in fig4 , the handle 13 d has reinforcement perpendicular and beneath the handle 13 d , opposite of the head 13 a . in the preferred embodiment , the reinforcement is a triangular shaped rib 13 e where the point of the triangle approaches the stem 13 c . at the opposite end of the rib 13 e , a grip 13 f attaches to the rib 13 e beneath the handle 13 d and the second plate 4 . in the preferred embodiment , the grip 13 f has a rectangular shape within the width of the handle 13 d . in use , a user places the lip 3 on a lateral edge 4 b of the second plate 4 opposite the pads 17 into the first plate 2 where no lip 3 is present . the lips 3 of the second plate 4 pass upon the glides 8 and slide beneath the surface of the first plate 2 . the second plate 4 within the first plate 2 forms the shelf 1 . the user then inserts the shelf 1 at an angle into a locker . the user then levels the shelf 1 , extends the first plate 2 and the second plate 4 outwards against the locker walls , and then reaches beneath the shelf 1 to grasp the crank 13 . turning the crank 13 , the user extends the second plate 4 relative to the first plate 2 then induces more friction between the pads 17 and the locker walls when the teeth 13 b engage the rack 12 as the user turns the crank 13 for a tight fit of the 1 shelf . when the crank 13 reaches the longitudinal axis of the shelf 1 , the user places the rib 13 e within the stops 14 to fix the crank 13 in place and the width of the shelf 1 . variations or modifications to the subject matter of this invention may occur to those skilled in the art upon reviewing the summary of the invention as defined herein , and upon undertaking a study of the description of its preferred embodiment . such variations , if within the spirit of this development , are intended to be encompassed within the scope of the invention as shown and described herein . the specific depiction of the invention , as described , and as shown in the drawings , is set forth for illustrative purposes only . from the aforementioned description , an adjustable shelf has been described . the adjustable shelf is uniquely capable of extending one plate relative to another plate to adjust the width of a shelf to meet various widths . the adjustable shelf and its various components may be manufactured from many materials including but not limited to polymers , high density polyethylene hdpe , polypropylene pp , polyethylene terephalate ethylene pete , polyvinyl chloride pvc , polystyrene ps , nylon , ferrous and non - ferrous metals , their alloys , and composites .
a shelf having two telescoping plates secured by a toothed crank is provided for locker users . the plates have a generally rectangular shape with perimeter edges reinforced by lips and pads to engage the locker walls . friction between the pads and the walls holds the present invention at a desired elevation . this shelf has a toothed rack upon a first plate and a crank with teeth upon the second plate . the teeth upon the crank engage the rack and turning of the crank secures the second plate relative to the first plate longitudinally at a desired width for fitting against the inner walls of a locker .