Abstract:
A plastic copyholder having a frame with track means and an arm having upper and lower surfaces. Adjustable elongated block means ride on the track means. Slide means in the block means permit unique pivoting and adjustment of the arm.

Description:
BACKGROUND OF THE INVENTION 
     A variety of arrangements for supporting foldable reader bars in adjustable positions have been proposed (U.S. Pat. Nos. 4,102,050; 4,267,656; 4,365,431; 1,175,448; and 694,389). 
     SUMMARY OF THE INVENTION 
     Broadly, the present invention is a foldable copyholder, preferably of assembled molded plastic parts, which includes an arrangement for moving the line guide up and down the copyholder face without the use of springs or magnetic means. The selected engagement of the stationary and moving parts is accomplished through sizing the parts, the elastic quality of the molded material, and other interactivity of parts as further described. 
     It is a feature that the line guide unit includes a movable track-carrying block and an extendable piece for accommodating the thickness of papers on the copyholder. 
     It is a further feature that the copyholder has a foldable stand which is firmly engageable in the copyholder frame mount when the stand is fully extended to its open position and by the application of modest force is readily moved to its folded position. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the copyholder in standing position; 
     FIG. 2 is an exploded view of the line guide unit; 
     FIG. 3 is a partial side elevational view of the line guide unit engaging the copyholder frame; 
     FIG. 4 is a sectional view of a clip unit engaging a section of the copyholder frame; 
     FIG. 5 is an exploded perspective view of the clip unit; 
     FIG. 6 is a perspective exploded view showing the frame-stand and copyholder retaining bar; 
     FIG. 7 is a side elevational view of the frame hinge in its open standing position; and 
     FIG. 8 is a partial perspective view of the stand and frame hinge arrangement in an exploded view. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In FIG. 1, copyholder 10 includes a planar sheet rest frame 11 including lower sheet support ledge 12, a lower sheet retaining bar 13, a foldable stand 14, and a movable line guide unit 16. Also shown are vertical frame grooves 11a, 11b and upper groove 11c. Frame 11 also includes vertical side pieces 17, 18 and top piece 15, all perpendicular to the plane of sheet rest frame 11. The frame 11 and other copyholder parts, as will be described hereinafter, are preferably molded plastic. Suitable plastics are A. B. S., styrene polypropylene, etc. The frame and other parts are relatively hard but sufficiently compressible and deflectable under load to permit the operations referred to herein. Parts that slide on one another are close fitting and rely on friction and movement arm forces to hold parts in selected positions. Interaction between parts, in static and dynamic conditions, including compressibility, deflectability, close tolerances, friction and torque are all herein referred to as &#34;interactivity&#34;. 
     Turning to FIGS. 2 and 3, line guide unit 16 includes a slidable plastic frame mount 19 pivotally connected to mount plate 22 and positioned to slide up and down with interactivity in plastic block 21. Block 21 slides on side piece 17 or 18 in close frictional tolerance with the weight of the arm 20 providing a torque to assist in holding the block 21 in any selected position. Guide unit 16 also includes plastic arm 20. Arm mount plate 22, in turn, includes two (2) spaced-apart axle mount pieces 26a, 26b secured to the underside of plate 22. Arm 20 carries holes 20a, 20b for connecting plate 22 to arm 20 by means of heat-staking posts 22a and 22b. Slidable frame mount 19 has two (2) pivot plates 29a, 29b spaced-apart to fit adjacent and inside mount pieces 26a, 26b with plate axles 29c, 29d snap fitting in plate receiving opening 26c, 26d. Plate projections 29e, 29f snap over plate ridges 26c and 26d (not shown) to hold frame mount 19 in a right angle orientation to arm 20. In such snap over position plate projection 29f is just to the right of plate ridge 26c (FIG. 2). 
     Frame mount 19 also includes body portion 32 with opposing L-shaped upstanding piece 31a and upstanding flat piece 31b. Flat piece 31b carries ledge tab 31c. Pieces 31a, 31b are deflectable about body 32 to fit with close frictional tolerances into box unit 21 having groove 21a, frame grip rack 21b, slot 21c and frame hook 21d. Frame mount 19 including L-shaped piece 31a and deflectable flat piece 31b are inserted into body unit 21 alonge groove 21a until tab 31c reaches the lower end of slot 21c (as shown in FIG. 2) which end is just above frame hook 21d. Once hook 21d reaches this point, frame mount 19 and box unit 21 are in snap engagement but can continue to move telescopically until grip rack 21b engages the surface of plate 22 or can move further apart until tab 31c is snapped into slot 21c (through tab 31c deflection). It is seen that when the end 32a of body 32 engages plate 22 and plate projection 29e, 29f are in snap position the plate 22 and arm 20 are in right angle orientation. 
     Turning to FIG. 3, the box unit 21 as mounted on rest frame 11 and particularly its vertical side piece 18. Body 32 is adjustable in unit 21 to accommodate for the desired spacing between arm 20 and rest frame 11. 
     FIGS. 4 and 5 show clip unit 33 including frame groove 11, slide frame 34, hinge extension 35 and pivotal clamp plate 36. Slide frame 34 has frame engaging rails 34a, 34b, hinge extension 35 has curved bearing hooks 35a, 35b and plate 36 has axles 36a, 36b to receive hooks 35a, 35b. Spring 37 urges plate 36 in a counterclockwise direction as shown in FIG. 4 to grip and hold sheets of paper or other objects against frame 11. Also shown is finger grip area 38 for facilitating squeezing unit 33 to overcome spring 37 and release engaged sheets of paper (not shown) between frame rest 11 and clamp plate 36. 
     In FIG. 6, there is shown rest frame 11, U-shaped stand 14 and support ledge 12. Also shown is retaining bar 13 which includes plastic projections 44, 45 and 46 each of which has spaced-apart projection arms 44a, 44b, 45a, 45b and 46a, 46b which arms are housed in frame arm receivers 48, 49, 50 sized to tension arms 44a, 44b, 45a, 45b and 46a, 46b toward one another to enable arms 44a, 44b and 45a, 45b, 46a, 46b to be inserted into arm receivers 48, 49, 50 until arm barbs 44c, 44d; 45c, 45d; 46c, 44d snap fit, for assembly purposes, by projecting below receivers 48, 49 and 50. Also shown are stand feet 52 and 53. U-shaped stand 14 includes base section 14a and stand legs 14b and 14c. 
     Turning in particular to FIGS. 7 and 8, U-shaped stand leg 14b has upper end pairs of spaced-apart projection pieces 54a, 54b having a rod 57 affixed between them. Mounted in and extending between pieces 54a, 54b are upstanding hinge rod bearing sections 55a and 55b attached to or formed in the back side of rest frame 11. Upstanding sections 55a, 55b include grooves 56a, 56b for receiving and holding rod 57 which carries integral bracing piece 58. Rod 57 fits through snap-in and snap-out engagement. Frame leg 14c is similarly constructed. Pivotal movement of legs 14b, 14c is limited by two spaced-apart frame uprights 60, 61 as rod element 58, an integral part of rod 57, engages them. 
     Preferably all parts of copyholder 10 are made of plastic parts without metal springs, fasteners or the like for ease of assembly, operation and durability.