Patent Publication Number: US-2017354245-A1

Title: Stand up desk having adjustable heights

Description:
This application claims priority from U.S. Provisional Application Ser. No. 62/348,540, entitled Stand Up Desk Having Adjustable Heights, filed Jun. 10, 2016. 
    
    
     FIELD OF THE INVENTION 
     Our invention relates generally to a stand up desk that is adjustable to variable heights. More specifically, our invention relates to an adjustable stand up desk that provides a user with an ergonomic work environment and thereby improves health of a user. 
     RELATED ART 
     Sitting for long periods of time can negatively impact a person&#39;s health. In fact, medical studies suggest that the more a person sits each day, the greater is their risk for chronic health problems, such as cancer, diabetes, and heart disease. Thus, office jobs that require long periods of sitting may be hazardous to a person&#39;s health due to inactivity and low levels of energy expenditure. 
     Allowing office workers or other “desk-bound” persons to stand for periods of time during the workday is one way to address these concerns. Standing at a desk, however, imposes costs and concerns, such as the need for a separate standing desk or replacing a sitting desk with a standing desk. As used herein, the term “standing desk” relates to a desk that a user would stand up to use, while the term “sitting desk” refers to a desk that a user would use while sitting down. One possible solution to these problems is to provide a variable height desk or surface that may be placed on an existing sitting desk. Current variable height desks, however, are bulky and heavy because of their elaborate height adjustment mechanisms. As used herein, the term “variable height desk” refers to a desk that is capable of being adjusted to various heights. In addition, the height adjustment mechanisms of these variable height desks often cause the desk to swing forward (towards the user and into the user&#39;s workspace) when being adjusted vertically in height, as opposed to moving directly upward in a vertical plane. This forward movement of the variable height desk causes the desk to intrude on the person&#39;s workspace. In the case of a cubicle worker, the amount of workspace is already quite limited. Thus, these current variable height desks are generally not feasible for many workers or workspace environments, while also lacking portability and ease in storage when not in use. Current variable height desks can also be difficult to adjust in height. Moreover, current variable height desks may not collapse into a flat or a low-profile configuration or a position that allows for a person to also use the desk in a seated position. 
     SUMMARY OF THE INVENTION 
     According to one aspect, our invention provides an adjustable stand up desk that includes a first desk surface and a second desk surface connected to the first desk surface. The desk further includes a base with at least two channels and a pair of positioning legs that is configured to sit on an existing desk. A folding leg assembly connects the base to at least the first desk surface. The folding leg assembly includes a first pair of legs that extends between the first desk surface and the base, and a second pair of legs that extends between the first desk surface and the base. Each leg of the first and second pairs of legs is configured to slide within the at least two channels of the base, such that the adjustable stand up desk can be adjusted from at least a closed position to a fully extended position. In one embodiment, the adjustable stand up desk can also be adjusted to a partially extended position. 
     According to another aspect, our invention provides an adjustable stand up desk that includes a first desk surface and a second desk surface connected to the first desk surface. The desk further includes a base with at least two channels and a pair of positioning legs that is configured to sit on an existing desk. A folding leg assembly connects the base to at least the first desk surface. The folding leg assembly includes a first pair of legs that extends between the first desk surface and the base, and a second pair of legs that extends between the first desk surface and the base. Each leg of the first and second pairs of legs is configured to slide within the at least two channels of the base, such that the adjustable stand up desk can be adjusted from at least a closed position to a fully extended position. The desk further includes a gas spring assembly that is configured to provide a controlled adjustment of the desk from at least the closed position to the fully extended position, and an operable handle and a handle assembly that are configured to engage with the gas spring assembly to assist in the adjusting of the desk from at least the closed position to the fully extended position. In one embodiment, the adjustable stand up desk can also be adjusted to a partially extended position. 
     Other aspects and advantages of the present invention will become apparent upon consideration of the following detailed description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a top perspective view of an adjustable stand up desk in a fully extended position, according to one embodiment of the invention. 
         FIG. 1B  is a top perspective view of the adjustable stand up desk shown in  FIG. 1A , showing the desk in use in a workspace environment according to one embodiment of the invention. 
         FIG. 2  is a front view of the adjustable stand up desk shown in  FIG. 1A  in the fully extended position. 
         FIG. 3  is a back view of the adjustable stand up desk shown in  FIG. 1A  in the fully extended position. 
         FIG. 4  is a right side view of the adjustable stand up desk shown in  FIG. 1A  in the fully extended position. 
         FIG. 5  is a left side view of the adjustable stand up desk shown in  FIG. 1A  in the fully extended position. 
         FIG. 6  is top view of the adjustable stand up desk shown in  FIG. 1A . 
         FIG. 7  is a bottom view of the adjustable stand up desk shown in  FIG. 1A . 
         FIG. 8  is a bottom perspective view of the adjustable stand up desk shown in  FIG. 1A , showing the underside of the desk. 
         FIG. 9  is a top perspective view of an adjustable stand up desk in a partially extended position, according to one embodiment of the invention. 
         FIG. 10  is a front view of the adjustable stand up desk shown in  FIG. 9  in the partially extended position. 
         FIG. 11  is a back view of the adjustable stand up desk shown in  FIG. 9  in the partially extended position. 
         FIG. 12  is a bottom perspective view of the adjustable stand up desk shown in  FIG. 9 , showing the underside of the desk. 
         FIG. 13  is a top side perspective view of an adjustable stand up desk in a closed position, according to one embodiment of the invention. 
         FIG. 14  is a front view of the adjustable stand up desk shown in  FIG. 13  in the closed position. 
         FIG. 15  is a back view of the adjustable stand up desk shown in  FIG. 13  in the closed position. 
         FIG. 16  is a partial, bottom perspective view of the adjustable stand up desk shown in  FIG. 13 , showing the underside of the desk. 
         FIG. 17  is a partial, bottom perspective view of a locking mechanism of the adjustable stand up desk, according to one embodiment of the invention. 
         FIG. 18  is a partial, bottom perspective view of the locking mechanism shown in  FIG. 17  in a locked position. 
         FIG. 19  is a partial, bottom perspective view of a handle assembly of the adjustable stand up desk, according to one embodiment of the invention. 
         FIGS. 20A and 20B  are partial, side perspective views of the handle assembly shown in  FIG. 19  in a lowered position and a raised position, respectively. 
         FIGS. 21A and 21B  are partial, bottom perspective views of the handle assembly shown in  FIG. 19  in a lowered position and a raised position, respectively. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Our invention relates to a stand up desk that is adjustable to variable heights. In particular, our invention relates to an adjustable stand up desk that can be placed on an existing sitting desk, table, or other flat surface. The adjustable stand up desk may be adjusted from a flat or a low-profile configuration to varying heights to accommodate workers and workspaces of various sizes. Moreover, our invention relates to an adjustable stand up desk that offers ease in height adjustment, portability, and storage, while also providing a user with an ergonomic work environment in order to improve health of a user. 
     Turning now to the drawings,  FIG. 1A  illustrates one embodiment of an adjustable stand up desk  100  according to the invention, in which the adjustable stand up desk  100  is in a fully extended position. As shown in  FIG. 1A , the adjustable stand up desk  100  includes a first desk surface  10 , a second desk surface  20 , a folding leg assembly  15 , and a base  30 . In the embodiment of  FIG. 1A , the base  30  comprises a plurality of frame members  30 A,  30 B,  30 C, and  30 D, with a first or rear frame member  30 A including a channel  32 A and a second or front frame member  30 B also including a channel  32 B (see, e.g.,  FIG. 8 ). These channels  32 A and  32 B are configured for guiding one or more wheels of the folding leg assembly  15 , which will be described in further detail below. The base  30  also includes a connection member  56  that connects at least the first frame member  30 A to the second frame member  30 B. The base  30  of the adjustable stand up desk  100  further includes one or more positioning legs  40 A and  40 B that are connected to one or more of the plurality of frame members  30 A- 30 D. The positioning legs  40 A and  40 B are configured to position the adjustable stand up desk  100  onto a flat surface, such as a desk or tabletop. For example, in one embodiment, such as the one shown in  FIG. 1B , the adjustable stand up desk  100  is positioned on top of a sitting desk  1000 , with a computer display monitor  1050  placed on top of the first desk surface  10 , and a keyboard  1060  and a mouse  1080  placed on top of the second desk surface  20 . Thus, according to one aspect of the invention, the adjustable stand up desk  100  is configured to be easily placed on top of an existing sitting desk, with the first desk surface  10  being generally used for the placement of one or more computer display monitors and/or laptop computers, and the second desk surface  20  being generally used for the placement of one or more computer keyboards, mouse, and/or other input devices. 
     As also shown in  FIGS. 1A, 2, 3, and 8 , the first desk surface  10  includes a frame system  12  that attaches to the bottom surface of the first desk surface  10  and extends below the first desk surface  10 . The frame system  12  includes a plurality of frame members  12 A,  12 B,  12 C, and  12 D, with a first frame member  12 A providing a channel  77 A, and a second frame member  12 B providing a channel  77 B (see, e.g.,  FIG. 8 ). These channels  77 A,  77 B are configured for guiding one or more wheels of the folding leg assembly  15 , which will be described in more detail below. The frame system  12  also includes a transverse connection member  76  that connects at least the first frame member  12 A to the second frame member  12 B. The frame system  12  also allows for connection of the first desk surface  10  to the second desk surface  20 . In particular, as shown in  FIGS. 1A, 4, and 5 , the first desk surface  10  is connected to the second desk surface  20  by one or more vertical brackets  70 A,  70 B, with each of the vertical brackets  70 A,  70 B attaching to a frame member  12 C or  12 D of the frame system  12  and one side of the second desk surface  20 . In one embodiment, such as the one shown in  FIGS. 4 and 5 , the vertical brackets  70 A,  70 B are attached to the respective frame member  12 C,  12 D of the frame system  12  by one or more nails or screws  72 ,  74 . The vertical brackets  70 A,  70 B, however, can be attached to the frame system  12  and the second desk surface  20  by any type of attachment element or mechanism (e.g., screws, nails, bolts, pins, glue, epoxy, etc.). 
     As also shown in  FIGS. 1A-6 , the second desk surface  20  includes a first handle  25 A on one side of the second desk surface  20  and a second handle  25 B on the other side of the second desk surface  20  (see, e.g.,  FIG. 6 ). The first and second handles  25 A,  25 B are provided for ease in adjusting the height of the adjustable stand up desk  100 . As also shown in  FIGS. 1A and 4 , an operable handle  80  is provided below the second handle  25 B of the second desk surface  20 . The operable handle  80  is connected to a rod  82  with first and second ends  84 ,  86 , and a handle assembly  85  that functions in accordance with movement of the operable handle  80 . The functioning of the operable handle  80  and the handle assembly  85  will be described in more detail below, with regards to  FIGS. 19-21B . Although in the embodiment of  FIGS. 1A and 4 , the operable handle  80  is provided below the second handle  25 B of the second desk surface  20 , the operable handle  80  can be provided below one or both of the first and second handles  25 A,  25 B of the second desk surface  20 . 
     One embodiment of the folding leg assembly  15  will now be described with reference to  FIGS. 1A-5, 7, and 8 . As shown in  FIGS. 1A-5, 7, and 8 , the folding leg assembly  15  includes a first pair of legs  50 A,  50 B and a second pair of legs  51 A,  51 B that each pivot about each other via a center bar  52  that connects each of the legs  50 A,  50 B,  51 A,  51 B together. The first pair of legs  50 A,  50 B and second pair of legs  51 A,  51 B are also slidably connected to the first desk surface  10  and the base  30 . In particular, as shown in  FIGS. 1A and 8 , a first end of each leg of the first pair of legs  50 A,  50 B terminates in or is connected to a first leg bar  60 A, while a second end of each leg of the first pair of legs  50 A,  50 B terminates in or is connected to a second leg bar  60 B. The first leg bar  60 A includes a pair of wheels  61 A,  61 B, with a first wheel  61 A of the pair of wheels  61 A,  61 B configured to roll within the channel  32 A provided by the first frame member  30 A of the base  30 , and a second wheel  61 B of the pair of wheels  61 A,  61 B configured to roll within the channel  32 B provided by the second frame member  30 B of the base  30 . The second leg bar  60 B includes a pair of wheels  63 A,  63 B, with a first wheel  63 A of the pair of wheels  63 A,  63 B configured to roll within the channel  77 A provided by the first frame member  12 A of the frame system  12 , and a second wheel  63 B of the pair of wheels  63 A,  63 B configured to roll within the channel  77 B provided by the second frame member  12 B of the frame system  12 . As shown in  FIGS. 1A and 8 , a first end of each leg of the second pair of legs  51 A,  51 B terminates in or is connected to a third leg bar  62 A, while a second end of each leg of the second pair of legs  51 A,  51 B terminates in or is connected to a fourth leg bar  62 B. The third leg bar  62 A includes a pair of wheels  66 A,  66 B, with a first wheel  66 A (not shown) of the pair of wheels  66 A,  66 B configured to roll within the channel  32 A provided by the first bracket  30 A of the base  30 , and a second wheel  66 B of the pair of wheels  66 A,  66 B configured to roll within the channel  32 B provided by the second bracket  30 B of the base  30 . The fourth leg bar  62 B includes a pair of wheels  67 A,  67 B, with a first wheel  67 A of the pair of wheels  67 A,  67 B configured to roll within the channel  77 A provided by the first frame member  12 A of the frame system  12 , and a second wheel  67 B of the pair of wheels  67 A,  67 B configured to roll within the channel  77 B provided by the second frame member  12 B of the frame system  12 . 
     As also shown in  FIGS. 1A-3 , a plurality of stabilizing struts  55 A- 55 D and  57 A- 57 D is provided, with each of the stabilizing struts  55 A- 55 B and  57 A- 57 D connecting to at least one of the legs of the first and second pairs of legs  50 A,  50 B,  51 A,  51 B. For example, as shown in  FIGS. 1A and 2 , a first stabilizing strut  55   a  connects to (i) a first leg  50 A of the first pair of legs  50 A,  50 B and (ii) the connection member  56  of the base  30 , while a second stabilizing strut  57 A connects to (i) a first leg  51 A of the second pair of legs  51 A,  51 B and (ii) the connection member  56  of the base  30 . The first and second stabilizing struts  55 A,  57 A are connected to the connection member  56  of the base  30  via a pivotal connection point  65 A, while at least the second stabilizing strut  57 A is connected to the first leg  51 A of the second pair of legs  51 A,  51 B via a pivotal connection point  54 A. As shown in  FIGS. 1A and 3 , a third stabilizing strut  55 B connects to (i) a second leg  50 B of the first pair of legs  50 A,  50 B and (ii) the connection member  56  of the base  30 , while a fourth strut  57 B connects to (i) a second leg  51 B of the second pair of legs  51 A,  51 B and (ii) the connection member  56  of the base  30 . The third and fourth stabilizing struts  55 A,  57 A are also connected to the connection member  56  of the base  30  via a pivotal connection point (not shown), while at least the fourth stabilizing strut  57 B is connected to the second leg  51 B of the second pair of legs  51 A,  51 B via a pivotal connection point  54 C. As further shown in  FIG. 2 , a fifth stabilizing strut  55 C connects to (i) the first leg  50 A of the first pair of legs  50 A,  50 B and (ii) the connection member  76  of the frame system  12 , while a sixth stabilizing strut  57 C connects to (i) the first leg  51 A of the second pair of legs  51 A,  51 B and (ii) the connection member  76  of the frame system  12 . As shown in  FIG. 8 , the fifth and sixth stabilizing struts  55 C,  57 C are connected to the connection member  76  of the frame system  12  via a pivotal connection point  65 B, while at least the sixth stabilizing strut  57 C is connected to the first leg  51 A of the second pair of legs  51 A,  51 B via a pivotal connection point  54 B. Moreover, as shown in  FIG. 3 , a seventh stabilizing strut  55 D connects to the second leg  50 B of the first pair of legs  50 A,  50 B and the connection member  76  of the frame system  12 , while an eighth stabilizing strut  57 D connects to the second leg  51 B of the second pair of legs  51 A,  51 B and the connection member  76  of the frame system  12 . As shown in  FIG. 8 , the seventh and eighth stabilizing struts  55 D,  57 D are connected to the connection member  76  of the frame system  12  via a pivotal connection point  65 C, while at least the eighth stabilizing strut  57 D is connected to the second leg  51 B of the second pair of legs  51 A,  51 B via a pivotal connection point  54 D. 
     The folding leg assembly  15  of the embodiment shown in  FIGS. 1A-5, 7, and 8  allows for the adjustable stand up desk  100  to be adjusted between at least a fully extended position (see, e.g.,  FIGS. 1A-5, 7, and 8 ), a partially extended position (see, e.g.,  FIGS. 9-12 ), and a closed or locked position (see, e.g.,  FIGS. 13-16 ), as well as any height in between the closed position and the fully extended position. For example, as shown in  FIGS. 1A and 2 , the adjustable stand up desk  100  is in the fully extended position when the first desk surface  10  extends a distance H 1  from the base  30 , with the distance H 1  being the maximum distance that the first desk surface  10  can extend away from the base  30 . As shown in  FIGS. 9 and 10 , the adjustable stand up desk  100  is in the partially extended position when the first desk surface  10  extends a distance H 2  from the base  30 , with the distance H 2  being the less than the distance H 1 . As shown in  FIGS. 13 and 14 , the adjustable stand up desk  100  is in the closed position when the first desk surface  10  extends a distance H 3  from the base  30 , with the distance H 3  being the minimum distance that the first desk surface  10  can extend away from the base  30 . In one embodiment, in the closed position (see, e.g.,  FIGS. 15 and 18 ), the adjustable stand up desk  100  can be locked through a locking mechanism. In one embodiment, as shown in  FIGS. 17 and 18 , the locking mechanism comprises a locking pin or screw  90  that engages with (i) an opening (not shown) provided in an outer surface of the first frame member  30 A of the base  30 , and (ii) an opening  59  provided within a locking bracket  58  that is attached to the second frame member  12 B of the frame system  12 . As shown in  FIGS. 17 and 18 , when the adjustable stand up desk  100  is shifted into the closed position, the opening  59  of the locking bracket  58  lines up with the opening of the first frame member  30 A of the base  30 , such that the locking pin or screw  90  can engage with the opening  59  of the locking bracket  58 . This engagement of the locking pin or screw  90  with the opening  59  of the locking bracket  58  allows for the folding leg assembly  15  and the adjustable stand up desk  100  to be locked into place when the adjustable stand up desk  100  is in the closed position (see, e.g.,  FIG. 15 ). 
     The folding leg assembly  15  adjusts the stand up desk  100  from the fully extended position to the closed position by shifting the legs  50 A,  50 B,  51 A,  51 B of the folding leg assembly  15  from a fully extended position (see, e.g.,  FIGS. 1A-3 and 8 ) to a collapsed and folded position (see, e.g.,  FIGS. 13-16 ). For example,  FIG. 8  is a bottom perspective view of the underside of the adjustable stand up desk  100  in a fully extended position. As shown in  FIG. 8 , each of the legs  50 A,  50 B,  51 A,  51 B are in a fully extended position, with (i) the second leg bar  60 B and pair of wheels  63 A,  63 B positioned within a central region of each of the channels  77 A,  77 B provided by the first and second frame members  12 A,  12 B of the frame system  12 , and (ii) the fourth leg bar  62 B and pair of wheels  67 A,  67 B positioned within a central region of each of the channels  77 A,  77 B provided by the first and second frame members  12 A,  12 B of the frame system  12 . In the fully extended position of the embodiment shown in  FIG. 8 , the first leg bar  60 A and pair of wheels  61 A,  61 B are also positioned within a central region of each of the channels  32 A,  32 B provided by the first and second frame members  30 A,  30 B of the base  30 , and the third leg bar  62 A and pair of wheels  66 A,  66 B are also positioned within a central region of each of the channels  32 A,  32 B provided by the first and second frame members  30 A,  30 B of the base  30 . As the adjustable stand up desk  100  is shifted from the fully extended position of, for example, the embodiment shown in  FIG. 8 , to the partially extended position of, for example, that shown in  FIGS. 9-12 , and/or the closed position of, for example, that shown in  FIGS. 13-16 , each of the wheels  61 A,  61 B,  63 A,  63 B,  66 A,  66 B,  67 A,  67 B is guided within their respective channel and rolls away from the center of the desk  100  and towards a respective side of the desk  100  (see, e.g., arrows A of  FIG. 12 ). In contrast, as the adjustable stand up desk  100  is shifted from the closed position of, for example, the embodiment shown in  FIGS. 13-16 , to the partially extended position of, for example, that shown in  FIGS. 9-12 , and/or the fully extended position of, for example, that shown in  FIGS. 1A-3 and 8 , each of the wheels  61 A,  61 B,  63 A,  63 B,  66 A,  66 B,  67 A,  67 B is guided within their respective channel and rolls toward the center of the desk  100  and away from a respective side of the desk  100  (see, e.g., arrows B of  FIG. 12 ). Moreover, as the wheels  61 A,  61 B,  63 A,  63 B,  66 A,  66 B,  67 A,  67 B are guided within their respective channels, the respective leg bars  60 A,  60 B,  62 A,  62 B are also shifted in the same direction as their respective wheels  61 A,  61 B,  63 A,  63 B,  66 A,  66 B,  67 A,  67 B, which in turn shifts the respective legs  50 A,  50 B,  51 A,  51 B into (i) a folded or closed position (see, e.g.,  FIGS. 13-16 ), (ii) a partially extended position (see, e.g.,  FIGS. 9-12 ), or (ii) an open or fully extended position (see, e.g.,  FIGS. 1A-3 and 8 ). 
     As discussed above, the folding leg assembly  15  adjusts the stand up desk  100  from a fully extended position to a closed position by shifting the legs  50 A,  50 B,  51 A,  51 B of the folding leg assembly  15  from a fully extended position to a collapsed and folded position. The movement and configuration of the folding leg assembly  15  allows for the adjustable stand up desk  100  to be adjusted from the closed position to the fully extended position in a directly vertical manner, such that the first desk surface  10  and/or the second desk surface  20  do not swing toward and/or away from the user during the adjusting of the stand-up desk  100 . This configuration of the adjustable stand up desk  100  allows for minimal space to be needed to adjust the desk  100  from the closed position to the fully extended position. Moreover, the adjustable stand up desk  100  does not intrude into the workspace of the user during and after the adjusting of the height of the stand-up desk  100 . Accordingly, this direct vertical adjustment of the stand-up desk  100  allows for the desk  100  to be effectively used in many types of work environments, including, for example, cubicle work units. 
     In one embodiment, as shown in  FIGS. 7 and 8 , the folding leg assembly  15  is connected to a commercially available gas spring assembly  200 , such as a lockable gas spring, type RLE from Lesjofors Springs and Pressings, to provide a controlled adjustment of the height of the stand-up desk  100 . The gas spring assembly  200  is connected to a handle assembly  85 , which in turn is connected to a manually operable handle  80 . Accordingly, operation of the handle  80  and handle assembly  85 , which will be described in further detail below, can control the position of an internal valve between a bi-chambered cylinder  220  to allow a push rod  210  to be extended or retracted relative to the cylinder. When the valve is in the closed position, the push rod  210  is locked relative to the cylinder and when the valve is open, fluid can flow between the internal chambers and the push rod can be extended or retracted. Handle  80  and handle assembly  85  control the position of the valve to control the movement of the adjustable stand up desk  100  and set the desk  100  at a desired height. For example, in one embodiment, the gas spring assembly  200  comprises a spring mechanism  201 , a push rod  210 , and a gas cylinder  220 . In one embodiment, the gas of the gas cylinder  220  comprises air however, the cylinder may work with other fluids. As shown in  FIGS. 7, 8, 12, and 16 , during height adjustment of the desk  100 , the gas cylinder  220  is mounted beneath the underside of the first desk surface  10 . In one embodiment, the spring mechanism  201  is connected to the second leg bar  60 B via a connecting member  201 A, while the gas cylinder  220  is connected to the fourth leg bar  62 B thus as the stand up desk  100  is adjusted from a closed position to a fully extended position, or vice versa the distance between second leg bar  60 B and fourth leg bar  62 B varies, such that pushrod  210  and a connected to a piston (not shown) that slides within the gas cylinder  220  must move relative to the cylinder. The movement of the piston increases or decreases pressure that is created within a chamber in the gas cylinder  220 . The push rod  210  is also connected to the spring mechanism  201 , such that energy created by the spring mechanism  201  can be dampened by the piston and/or gas cylinder  220 . In one embodiment, the spring mechanism  201  is connected to the second leg bar  60 B via a connecting member  201 A, while the gas cylinder  220  is connected to the fourth leg bar  62 B. Accordingly, the movement of the wheels  63 A,  63 B,  67 A,  67 B within their respective channels and the movement of the respective leg bars  60 B,  62 B results in either compression or extension of the spring mechanism  201  and movement of the gas cylinder  220 . In one embodiment, the spring mechanism  201  is fully extended when the adjustable stand up desk  100  is in the closed position (see, e.g.,  FIG. 16 ). In this fully extended position, the spring mechanism  201  is charged because energy is being stored by the spring mechanism  201 . This stored energy of the fully extended spring mechanism  201  can provide the force needed to lift the adjustable stand up desk from the closed position to the fully extended position. This force, however, is dampened by the movement of the piston within the gas cylinder  220 , as the gas cylinder  220  and push rod  210  extend or retract, such that the stored energy from the fully extended spring mechanism  201  is released in a controlled and gradual manner. By allowing for this controlled release of the stored energy created by the spring mechanism  201 , the height of the stand-up desk  100  can also be adjusted in a controlled manner. In this embodiment, once the adjustable stand up desk  100  is set to the partially or fully extended position, the spring mechanism  201  will be compressed, which will release some or all of the stored energy. Thus, the user will need to provide force to shift the adjustable stand up desk  100  back to the closed position, which in turn will fully extend the spring mechanism  201  and charge the spring mechanism  201  with energy again. The spring mechanism  201  can comprise a coil or helical spring, a tension or extension spring, a torsion spring, and/or a compression spring. 
     In the illustrated embodiment, the gas spring assembly  200  is connected to the handle assembly  85 , which in turn is connected to the operable handle  80 . Accordingly, operation of the handle  80  and handle assembly  85 , which will be described in further detail below, can actuate or control position of the valve within cylinder  220 , such that the release of the handle  80  can stop the movement of the adjustable stand up desk  100  and set the desk  100  at a desired height. For example, in the embodiment of  FIGS. 4 and 19-21B , the operable handle  80  is connected to a rotatable rod  82  having a first end  84  and a second end  86 . The first end  84  of the rod  82  is connected to either a side of the second desk surface  20  or a portion of the vertical bracket  70 A, while the second end  86  of the rod  82  is connected to a portion of the vertical bracket  70 A. The rod  82  is further connected to the handle assembly  85 . The handle assembly  85  includes a hinging member  300 , a biasing member  310 , a rod member  320 , and an attachment structure  330 . The hinging member  300  includes a first portion  300 A, a second portion  300 B, and a third portion  300 C that connects to the rod member  320 . The first portion  300 A of the hinging member  300  is connected at (i) a first end to the rotatable rod  82  and (ii) a second end to the second portion  300 B via a pivot point  301 . The second portion  300 B of the hinging member is connected at (i) a first end to the first portion  300 A via the pivot point  301  and (ii) a second end to the third portion  300 C via a pivot point  302 . The third portion  300 C is connected to the rod member  320 , which rotates within the attachment structure  330 . The attachment structure  330  attaches the handle assembly  85  to the vertical bracket  70 A. As the user operates the handle  80  and shifts the handle  80  from a downward position (see, e.g.,  FIG. 20A ) to an upward position (see, e.g.,  FIG. 20B ), the rotatable rod  82  is rotated, which in turn shifts the hinging member  300  upwardly. The movement of the hinging member  300  upwardly also shifts the first, second, and third portions  300 A,  300 B,  300 C upwardly, such that the third portion  300 C presses against the biasing member  310  and biases the biasing member  310  upwardly (see, e.g.,  FIG. 21B ). The biasing member  310  is configured to interact with the gas spring assembly  200  such as by engaging a push pin controlling the position of the internal valve, such that movement of the biasing member  310  can cause the gas cylinder  220  to unlock the push rod  210  and allows for the controlled adjustment in height of the adjustable stand up desk  100 . Accordingly, as a user presses up on the operable handle  80 , the stand up desk  100  can be adjusted between the closed position and the fully extended position, or vice versa. Once the user releases the operable handle  80 , the rotatable rod  82  returns the hinging member  300  to the downward position, which in turn causes the third portion  300 C to stop pressing on the biasing member  310  and return the biasing member  310  to its original position (see, e.g.,  FIG. 21A ). This return of the biasing member  310  returns the push rod  210  and cylinder  220  to their locked condition, such that the movement or adjustment in the height of the adjustable stand up desk  100  can be prevented. Accordingly, the adjustable stand up desk  100  can be set at a desired height by release of the operable handle  80 . It is to be understood that releasably locking gas springs are well known and any compatible gas spring may be used. 
     Illustrative materials that can be used to form the various components of the adjustable stand up desk  100  discussed above include, for example, wood, particleboard, medium-density fiberboard (MDF), thermofoil, metal (such as, for example, steel or aluminum), non-metallic materials, plastics, rubber, and combinations thereof In one embodiment, various components of the adjustable stand up desk  100  comprise aluminum, which is a lighter weight metal, and, thus, reduces the weight of the desk  100 . In another embodiment, various components of the adjustable stand up desk  100  comprise steel, which is generally lower in cost and provides a higher strength than aluminum. Those skilled in the art will recognize that a wide variety of other materials may also be used to form the various components of the adjustable stand up desk  100 . Moreover, the thickness of the various components of the adjustable stand up desk  100  discussed above including, for example, the first and second desk surfaces  10 ,  20  will depend on the material used and the amount of stiffness desired, among other factors. In addition, in one embodiment, at least one of the first desk surface  10  and the second desk surface  20  may include a protective cover (not shown) that minimizes damage to a top surface of the first and/or second desk surface  10 ,  20 . In one embodiment, the protective cover uses powder coating technology whereby a free flowing, dry powder is applied electrostatically and then is cured under heat to allow powder to flow and form the protective cover. The powder may be a thermoplastic or a thermoset polymer. Alternatively, other materials may be used as the protective cover. 
     The various components of the adjustable stand up desk  100  discussed above, including, for example, the various frame members, brackets, rods, wheels, and connecting members can be attached to other components of the desk  100  via welding, brazing, or other affixing methods, including, for example, nails, screws, bolts, pins, glues, and/or other epoxies. 
     Although the embodiments of the adjustable stand up desk  100  discussed above include first and second desk surfaces  10 ,  20  that are rectangular in shape, the first and second desk surfaces  10 ,  20  may be fabricated in other shapes, including, for example, round, square, or oval. In addition, it should be noted that, although the adjustable stand up desk  100  described herein includes first and second desk surfaces  10 ,  20 , other embodiments of the adjustable stand up desk  100  can include only a single desk surface or three or more desk surfaces of various shapes and/or sizes. Furthermore, it is contemplated that parts and features of any one of the specific embodiments of the adjustable stand up desk  100  discussed above, can be interchanged with parts and features of any other embodiments without departing from the spirit of the invention. 
     Although this invention has been described with respect to certain specific exemplary embodiments, many additional modifications and variations would be apparent to those skilled in the art in light of this disclosure. It is, therefore, to be understood that this invention may be practiced otherwise than as specifically described. Thus, the exemplary embodiments of the invention should be considered in all respects to be illustrative and not restrictive, and the scope of the invention to be determined by any claims supportable by this application, and the equivalents thereof, rather than by the foregoing description. 
     INDUSTRIAL APPLICABILITY 
     The adjustable stand up desk described herein provides a variable height desk that can be placed on an existing sitting desk. The adjustable stand up desk can provide a user with an ergonomic work environment and thereby improve health of a user.