Abstract:
An adjustable armrest with an central core with a longitudinal channel, a locking slide slidably received in the longitudinal channel, and locking members retained by the central core. The locking slide has a first position wherein the locking members are pressed to a position projecting outboard of the elongate central core and a second position wherein the locking members are permitted to retract within the elongate central core. An elongate core sleeve receives the elongate central core, and the core sleeve has a plurality of longitudinally spaced inlets and ridges. A first arm portion is fixed in relation to the elongate central core, and a second arm portion fixed in relation to the elongate core sleeve. The first arm portion can be extended and retracted in relation to the second arm portion by an actuation of the locking slide from the first position to the second position.

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to seating structures. More particularly, disclosed herein is an adjustable armrest for task chairs and similar seating constructions. 
     BACKGROUND OF THE INVENTION 
     It will be appreciated that a multitude of adjustable armrests for task chairs have been disclosed by the prior art. However, it is recognized that stability and reliability continue to be recognized challenges for the adjustable armrest structures of the prior art. Moreover, smooth and easy operation remain relatively elusive in the field of adjustable armrests. Instead, many armrests of the prior art are wobbly and prone to malfunction and unreliable operation. 
     Accordingly, an adjustable armrest that is stable, smooth and easy in operation, and reliable would represent a useful advance in the art. 
     SUMMARY OF THE INVENTION 
     Accordingly, the present invention is founded on the basic object of providing an adjustable armrest for seating that is stable and reliable. 
     A further object of embodiments of the invention is to provide an adjustable armrest for seating that is smooth and convenient in operation. 
     These and further objects and advantages of the present invention will become obvious not only to one who reviews the present specification and drawings but also to those who have an opportunity to experience an embodiment of the adjustable armrest disclosed herein in operation. However, it will be appreciated that, although the accomplishment of each of the foregoing objects in a single embodiment of the invention may be possible and indeed preferred, not all embodiments will seek or need to accomplish each and every potential advantage and function. Nonetheless, all such embodiments should be considered within the scope of the present invention. 
     One will appreciate that the foregoing discussion broadly outlines the more important goals and features of the invention to enable a better understanding of the detailed description that follows and to instill a better appreciation of the inventor&#39;s contribution to the art. Before any particular embodiment or aspect thereof is explained in detail, it must be made clear that the following details of construction and illustrations of inventive concepts are mere examples of the many possible manifestations of the invention. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       In the accompanying drawing figures: 
         FIG. 1  is a perspective view of an adjustable armrest according to the invention disclosed herein; 
         FIG. 2  is an exploded perspective view of the adjustable armrest of  FIG. 1 ; 
         FIG. 3  is a sectioned view in front elevation of an adjustable armrest as disclosed herein; 
         FIGS. 4, 5A, and 5B  are perspective views of an armrest pad according to the invention in various stages of assembly; 
         FIGS. 6 through 14  are perspective views of the components of the adjustable armrest in sequential stages of assembly; and 
         FIG. 15  is a top plan view of left and right adjustable armrests with the armrest pad in varied positions. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     The adjustable armrest disclosed herein is subject to a wide variety of embodiments. However, to ensure that one skilled in the art will be able to understand and, in appropriate cases, practice the present invention, certain preferred embodiments of the broader invention revealed herein are described below and shown in the accompanying drawing figures. Therefore, before any particular embodiment of the invention is explained in detail, it must be made clear that the following details of construction and illustrations of inventive concepts are mere examples of the many possible manifestations of the invention. 
     Looking more particularly to the drawings, an adjustable armrest according to the invention is indicated generally at  10  in  FIGS. 1 through 3 . Further, the components of the adjustable armrest  10  are illustrated in sequential stages of assembly in  FIGS. 6 through 14 . It will be understood that, while only one adjustable armrest  10  is shown in many of the accompanying drawings, the opposite armrest  10  will be a mirror image thereof. 
     The depicted armrest  10  can be considered to be founded on a lower casting  44  that would typically be fastened, such as by mechanical fasteners or otherwise, to a chair body (not shown) passed through apertures in a base plate  62  of the lower casting  44 . The lower casting  44  has a rigid sleeve portion  45  that can have, for example, a D-shaped cross section. 
     An outer bottom sleeve half  22  has a C-shaped cross section and is received into the curved outer segment of the sleeve portion  45  of the lower casting  44  such that outer sleeve half  22  and the sleeve portion  45  have substantially corresponding shapes. Inner bottom sleeve half  42  is received into the flat inner segment of the sleeve portion  45  of the lower casting  44 . The inner sleeve half  42  and the sleeve portion  45  have substantially corresponding shapes. 
     An outer core sleeve half  46  and an inner core sleeve half  24  are received into a volume defined within the outer bottom sleeve half  22  and the inner bottom sleeve half  42 . A locking disk  48  is matingly received into correspondingly shaped channels in the lower ends of the outer core sleeve half  46  and the inner core sleeve half  24 . Each of the sleeve halves  24  and  46  has a longitudinal channel therein with a series of longitudinally spaced inlets therealong with interposed ridges. Inner and outer top sleeve halves  20  and  34  are received by the inner and outer bottom sleeve halves  42  and  22 , and a central core  32  is disposed between the inner and outer top sleeve halves  20  and  34 . An upper casting  36  is disposed to house the inner and outer top sleeve halves  20  and  34  and the components therewithin. The series of sleeves formed by the sleeve halves  20 ,  22 ,  24 ,  34 ,  42 , and  46  provides inner and outer core stability to the upper casting  36  as the armrest  10  is telescoped up and down. 
     An armrest pad  12  is secured to the upper end of the upper casting  36 . A top plate  28  of the armrest pad  12  is retained relative to the upper end of the upper casting  36  by a lock plate  14  in combination with mechanical fasteners, a locking ring  26 , and a washer  16 . As described further hereinbelow, the armrest pad  12  and the top plate  28  can be pivoted about a longitudinal axis of the upper casting  36  to rest in one of a plurality of angular positions. 
     Another refinement of the adjustable armrest  10  can be perceived by further reference to  FIGS. 4, 5A, and 5B  where the armrest pad  12  is shown alone. There, the underside of the pad  12  can be seen to have a groove  64  along the edge thereof to facilitate the fastening of upholstery, such as by stapling, adhesive, spline, or some other method or combination thereof. The base plate  66  of the pad  12  has a cover  68  applied thereto for shielding the overlapping portions of the groove  64  and the upholstery. The tip portion of the pad  12  is shielded for modesty and structural purposes by a cap  50 . The tip portion of the base plate  66  of the pad  12  has an overturned tooth hook  52  that projects posteriorly therefrom. The cap  50  has a receiver, such as an aperture or groove, therein for receiving and engaging the tooth hook  52  thereby to retain the cap  50 . The cover  68  and the cap  50  thus cooperate to provide a continuous and protected feel and appearance along the lower face of the arm pad  12 . 
     Height adjustment of the armrest  10  is accomplished by actuation of a locking slide  18  by use of a trigger handle  30 . The locking slide  18  is biased to a lowered position by a coil spring  40  and has a tapered and narrowed distal portion that engages first and second locking cylinders  38 . When the locking slide  18  is released, the cylinders  38  will tend to lock within opposed inlets along the sleeves  24  and  46 . When the locking slide  18  is actuated as by pulling on the trigger handle  30  to lift the locking slide  18  against the biasing force of the spring  40 , the tapered and narrowed portion of the locking slide  18  will align with the locking cylinders  38  so that they will be permitted to exit the inlets thereby to permit a telescoping of the armrest  10 . Under the foregoing construction, the adjustable armrest  10  is stable, smooth, and reliable in structure and operation. 
     Further understanding of the structure and function of the adjustable armrest  10  can be had by additional reference to  FIGS. 6 through 14 , which show the components of the adjustable armrest  10  in sequential assembly steps. With reference to  FIG. 6 , during a first stage of assembly, the locking slide  18  and the central core  32  are lubricated, and the spring  40  is coupled at a first end to the lower end of the locking slide  18  and at a second end to a lower portion of the central core  32  as by being connected to a post. The locking slide  18  is secured to the central core  32  by a shoulder screw such that the locking slide  18  can still be slid longitudinally, such as by operation of the trigger  54 . 
     The first and second locking cylinders  38  are inserted into the central core  32  to project partially through windows  70  in opposed front and rear walls of the central core  32  that define a receiving channel for the locking slide  18 . The locking slide  18  is then inserted into the receiving channel with the body portion of the locking slide  18  locking the locking cylinders  38  in place projecting partially through the windows  70 . As noted above, when the central core  32  and the locking slide  18  are so assembled, actuation of the locking slide  18  by pulling on the trigger handle  30  and thus the handle  54  will lift the locking slide  18  against the biasing force of the spring  40  to cause the tapered or narrowed lower portion of the locking slide  18  to be disposed adjacent to the locking cylinders  38 . With that, the cylinders  38  are permitted to move inwardly no longer to project through the windows  70 . When the armrest  10  is fully assembled, the inward movement of the locking cylinders  38  will permit their disengagement from the inlets in the inner and outer core sleeve halves  24  and  46  thereby to permit a telescopic raising and lowering of the upper portion of the adjustable armrest  10 . 
     In a subsequent stage of assembly as depicted in  FIGS. 7 and 8 , the inner top sleeve half  20  and the outer top sleeve half  34  can be coupled in a facing relationship and then inserted longitudinally into the upper casting  36  through the open end thereof. The outer top sleeve half  34  has a longitudinal slot  56  at the upper end thereof, and the upper casting  36  has a longitudinal slot  58  at the upper end thereof in alignment with the longitudinal slot  56  in the outer top sleeve half  34 . The longitudinal slots  56  and  58  align with and permit longitudinal movement of the trigger  54  and the trigger handle  30 . 
     Looking to  FIG. 9 , the assembled locking slide  18  and central core  32  can then be slid longitudinally into the upper casting  36  from the upper end thereof to cause the trigger  54  to align with the longitudinal slots  56  and  58 . The locking slide  18  and the central core  32  can be secured in place by mechanical fasteners (shown in  FIG. 2 ) passed through a flange fixed to the upper end of the central core  32  and into the upper end of the upper casting  36 . 
     Then, as seen in  FIG. 10 , the inner and outer core sleeve halves  24  and  46  can be joined with the locking disc  48  of  FIG. 2  ensuring proper alignment and positioning between the sleeve halves  24  and  46  and the inlets and ridges of the inner faces thereof. The assembled sleeve halves  24  and  46  form a complete sleeve that can then be slid longitudinally into the assembled upper casting  36  and the inner top sleeve half  20  and the outer top sleeve half  34  such that the outer core sleeve halves  24  and  46  longitudinally receive the locking slide  18  and the central core  32  therein. To permit this sliding reception, the trigger handle  30  must be actuated to permit the locking cylinders  38  to clear way to permit their passage past the inlets and ridges of the inner faces of the sleeve halves  24  and  36 . Once the sleeve halves  24  and  46  are positioned as desired, the trigger handle  30  can be released thereby to push the locking cylinders  38  through the windows  70  and into the adjacent inlets thereby locking the sleeve formed by the sleeve halves  24  and  46  in a given longitudinal position. When the components are so assembled, the lower end of the assembly formed by the sleeve halves  24  and  46  projects beyond the lower end of the upper casting  36 , and a peripheral retaining ridge  72  encircles the lower end of the assembled sleeve halves  24  and  46 . 
     With the parts so assembled, the outer bottom sleeve half  22  and the inner bottom sleeve half  42  can be disposed to encase the lower portion of the upper casting  36  as shown in  FIGS. 11A and 11B . The outer and inner bottom sleeve halves  22  and  42  have inwardly facing retaining channels for matingly engaging and longitudinally retaining the peripheral retaining ridge  72  of the lower end of the assembled sleeve halves  24  and  46 . With that, when the outer and inner bottom sleeve halves  22  and  42  encase the upper casting  36 , the lower ends of the core sleeve halves  24  and  46  will be fixed against relative longitudinal movement while the upper casting  36  will be permitted to slide longitudinally upon an actuation of the trigger handle  30  and the underlying trigger  54 . 
     In a further assembly stage as shown in  FIG. 12 , the assembly formed with, among other components, the outer and inner bottom sleeve halves  22  and  42  can be slid longitudinally into the lower casting  44  through the open upper end thereof until upper flange edges of the outer and inner bottom sleeve halves  22  and  42  contact the upper rim of the lower casting  44 . A fastener  76  can then be passed through the lower end of the lower casting  44  and into the upper assembly to engage the locking disk  48  thereby to secure the lower casting  44  to the assembled core sleeve halves  24  and  46  while permitting a selective raising and lowering of the upper casting  36 . 
     Assembly can continue by fastening the top plate  28  to the upper end of the upper casting  36 . To do so, a washer  16  is disposed atop the upper end of the upper casting, the tope plate  28  is disposed atop the washer  16 , a locking ring  26  atop the top plate  28 , and a lock plate  14  atop the locking ring  26 . Then, mechanical fasteners are passed through the lock plate  14  and into the mating head  60  of the upper casting  36  thereby to fasten the top plate  28  in place. The armrest pad  12  can then be fastened to the top plate  28  by further mechanical fasteners passing through the top plate  28  and into the base plate  66  of the armrest pad  12 . 
     Looking additionally to  FIG. 15  where left and right adjustable armrests  10 A and  10 B are shown, it can be seen that the armrest pads  12 A and  12 B can be selectively pivoted about longitudinal pivot axes PA in relation to the upper castings  36 A and  36 B to rest in one of a plurality of angular positions. More particularly, in this example of the invention, the armrest pad  12  can be pivoted to and from a first angular position in longitudinal alignment with the chair (not shown) to which the armrests  10 A and  10 B are attached through the base plates  62 A and  62 B, a second angular position pivoted outboard by 22.5 degrees, and a third angular position pivoted outboard by 45 degrees. To facilitate the pivoting of the armrest pad  12 , looking again to  FIG. 13 , the locking ring  26  and the lock plate  14  can have spaced eccentricities that act as stops and guides to the pivoting of the armrest pad  12 . 
     With certain details and embodiments of the present invention for an adjustable armrest  10  disclosed, it will be appreciated by one skilled in the art that numerous changes and additions could be made thereto without deviating from the spirit or scope of the invention. This is particularly true when one bears in mind that the presently preferred embodiments merely exemplify the broader invention revealed herein. Accordingly, it will be clear that those with major features of the invention in mind could craft embodiments that incorporate those major features while not incorporating all of the features included in the preferred embodiments. 
     Therefore, the following claims shall define the scope of protection to be afforded to the inventor. Those claims shall be deemed to include equivalent constructions insofar as they do not depart from the spirit and scope of the invention. It must be further noted that a plurality of the following claims may express certain elements as means for performing a specific function, at times without the recital of structure or material. As the law demands, any such claims shall be construed to cover not only the corresponding structure and material expressly described in this specification but also all equivalents thereof.