Abstract:
An articulated stand having an adjustment mechanism featuring a hinge-and-wheel assembly. In one embodiment, the present invention provides an articulated, adjustable stand comprising an upwardly extending arm, a downwardly extending leg pivotally attached to the upwardly extending arm, a wheel rotatably mounted to a first end of the downwardly extending leg, and a spring element connecting the first arm member and the second leg member.

Description:
RELATED APPLICATION 
     The present application claims priority from U.S. Design patent application Ser. No. 29/155,987, filed Feb. 21, 2002 and entitled “Desk Lamp.” 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to an adjustable, articulated stand and, in one embodiment, to an adjustable, articulated stand for use in connection with a light source to form a desk lamp. 
     BACKGROUND OF THE INVENTION 
     Adjustable stands, such as those used in connection with desk lamps, of a variety of configurations are known in the art. Indeed, the prior art is replete with a wide variety of hinge and joint configurations to allow users to adjust the stands to a desired height and/or position. For certain uses of adjustable stands, such as desk lamps, a unique overall and/or mechanical design is desirable. 
     While the adjustable stands of the prior art fulfill their respective objectives, the prior art does not teach or suggest an articulated, adjustable stand including a novel hinge-and-wheel assembly as more fully described below. 
     SUMMARY OF THE INVENTION 
     The present invention provides an articulated stand having a novel adjustment mechanism featuring a hinge-and-wheel assembly. In one embodiment, the present invention provides an articulated, adjustable stand comprising an upwardly extending arm, a downwardly extending leg pivotally attached to the upwardly extending arm, a wheel rotatably mounted to a first end of the downwardly extending leg, and a tensile element connecting the first arm member and the second leg member. The adjustable stand, according to one embodiment, is movable between a most upright position and a lowest position. In one embodiment, the tensile element biases the leg toward the arm as the stand is adjusted from a lower position toward the most upright position. As the Figures illustrate, the adjustable stand can be used in connection with a light source to create a novel desk lamp. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a desk lamp including the articulated stand according to an embodiment of the present invention. 
     FIG. 2 is a side plan view illustrating the articulated stand oriented in a first position. 
     FIG. 3 is a side plan view illustrating the articulated stand oriented in a second position. 
     FIG. 4 is an exploded perspective view of the pivotal joint or attachment between the upwardly projecting arm and the downwardly projecting leg of the stand according to one embodiment of the present invention. 
     FIG. 5 is a sectional view illustrating a spring connecting the upwardly projecting arm and the downwardly projecting leg of the stand according to one embodiment of the present invention. 
     FIG. 6 is a side plan view setting forth an articulated stand according to another embodiment of the present invention. 
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     As the various Figures illustrate, the present invention provides an adjustable, articulated stand suitable for use in connection with a light source to form a desk lamp  10  and the like. The articulated, adjustable stand of the present invention can also be used to support a fan, medical instrument, etc. 
     As FIG. 1 shows, desk lamp  10 , in one embodiment, comprises cylindrical base  12 , upwardly projecting arm  14 , downwardly projecting leg  20 , wheel  30 , and light source  40 . Upwardly projecting arm  14 , in one embodiment, comprises first arm section  16  and second arm section  18 . In one embodiment, second arm section  18  is smaller in diameter to first arm section  16  and extends from a hole in first arm section  16 . In one embodiment, a set screw (not shown) holds second arm section  18  in place relative to first arm section  16 . Of course, any suitable method for attaching first and second arm sections  16  and  18  can be used. As FIG. 1 provides, upwardly projecting arm  14 , in one embodiment, extends from cylindrical base  12 . The cross-sectional shape of base  12 , however, need not be cylindrical; rather, base  12  can have any suitable cross sectional shape, such as triangle, square, polygon, etc. 
     As FIG. 1 illustrates, downwardly projecting leg  20  is a U-shaped member including first and second leg sections  21  and  22  extending from opposite ends of bend region  23 . Projecting leg  20  is pivotally attached to arm  14  (in one embodiment, to first arm section  16 ) at joint  25 . As FIG. 1 illustrates, in one embodiment, first and second leg sections  21  and  22  pivotally attach to opposite sides of first arm section  16  at joint  25 . In addition, wheel  30  rotatably attaches to first and second leg sections  21  and  22  at axis  32 . Wheel  30  can be any suitable wheel; in one embodiment, wheel  30  is a rubberized wheel similar to a wheel used in connection with in-line roller skates or rollerblades. As with such wheels, wheel  30  may optionally include components to facilitate smooth rotation such as ball bearings and the like. 
     As FIGS. 1 and 5 illustrate, lamp  10  further comprises spring  50  attached at one end to downwardly projecting leg  20  at cross bar  52 , and at the other end to first arm section  16 . In one embodiment, spring  50  attaches to first arm section with a book at one end of spring  50  that extends through a hole or two holes in first arm section  16 . In one embodiment, the other end of spring  50  includes a loop that extends around cross bar  52 . Of course, any suitable method for attaching spring  50  can be used. Spring  50  can be a standard steel coil spring, as well as any other suitable component that possesses sufficient tensile qualities, such as a section of elastic material, such as a section of rubber or other elastomeric material, and the like. 
     FIG. 4 illustrates an assembly associated with joint  25  between upwardly projecting arm  14  and downwardly projecting leg  20 . As FIG. 4 provides, the assembly comprises bolt  61  including head  60  and threaded region  62 , spacer ring  63 , and nut  67 . In one embodiment, the surfaces of head  60  and nut  67  are knurled to allow a user to tighten the assembly by hand. As FIG. 4 illustrates, bolt  61  extends through spacer ring  63  and holes  65  and  66 . Spacer ring  63  engages and extends with hole  65  to contact the outer surface of first arm section  16 . Nut  67  engages threaded region  62  of bolt  61 . As the assembly is tightened, head  60  presses spacer ring  63  against the outer surface of first arm section  16  to thereby, among other things, increase the friction between the outer surface of first arm section  16  and leg section  21 . Accordingly, adjustment of the joint assembly increases/decreases the friction associated with the joint and, therefore, the ease with which leg  20  moves relative to arm  14 . Of course, any suitable assembly for imparting the requisite friction at joint  25  can be used. 
     FIGS. 2 and 3 illustrate the range of adjustability associated with one embodiment of the present invention. When lamp  10  is oriented in its most upright position (FIG.  2 ), spring  50 , in one embodiment, is in an un-tensioned or slightly-tensioned state. The combination of frictional force provided by the assembly discussed above and the tensional force provided by spring  50  holds lamp  10  in position. However, as light source  40  is lowered, the moment provided by the weight of light source increases. However, as light source  40  is lowered, the tension of spring  50  increases to compensate for the increased moment. Again, the friction provided at joint  25 , in combination with spring  50 , further operates to hold the assembly in any desired position between the most upright position (FIG. 2) and the lowest position (FIG.  3 ). In addition, spring  50  also biases downwardly projecting leg  20  towards upwardly projecting arm  14  (back to its most upright position) when the user adjusts lamp  10  from a lower position to a higher position. In addition, as lamp  10  is raised and lowered, wheel  30  rotates; further, lamp  10  pivots about the point where cylindrical base  12  contacts the surface upon which lamp  10  is placed 
     Although the embodiment described above utilizes both the friction at joint  25  and spring  50 . Other embodiments can use either the friction at joint  25  or spring  50  as the sole means of holding lamp  10  in a desired orientation. However, it will be appreciated that the embodiment including a spring (with or without induced friction at joint  25 ) is preferred as spring  50  retracts downwardly projecting leg  20  as lamp  10  is raised. Accordingly, without spring  50 , the user must manually retract downwardly projecting leg as lamp  10  is raised from a lower position. 
     As FIG. 1 also shows, lamp  10  further includes light source  40  attached to the outer end of projecting arm  14 . In one embodiment, light source  40  is pivotally attached to second arm section  18  via a ball joint. Lamp  10 , in one embodiment, further comprises stem  42  extending from light source  40  to facilitate adjustment of light source  40 . Light source  40  can be any shape and configuration, such as a half dome, half cylinder, etc. In addition, light source  40  may comprise a standard bulb, a fluorescent bulb, a halogen bulb, or the like. As FIG. 1 provides, cord  44 , in one embodiment, extends from light source  40  through first and second arm sections  16  and  18  and out a hole in first arm section  16  (see FIG.  1 ). Cord  44  further includes a conventional electrical plug (not shown) at the end opposite light source  44 . In another embodiment, however, light source  44  may be battery powered, potentially obviating the need for cord  44  and an electrical plug. 
     In addition, FIG. 6 provides an alternative embodiment of the present invention. As FIG. 6 shows, the positions of wheel  30  and base  12  are switched. Specifically, base  12  is attached to downwardly projecting leg  20 , while wheel  30  is rotatably mounted to the bottom end of upwardly projecting arm  14 . Otherwise, this embodiment is substantially the same as that described above. 
     Lastly, although the present invention has been described with reference to specific embodiments, various other embodiments are possible without departing from the scope of the present invention. Other embodiments of the present invention will be apparent to one of ordinary skill in the art. It is, therefore, intended that the claims set forth below not be limited to the embodiments described above.