Abstract:
A writing table having elbow supporting plate connected with drawer includes a push-and-pull big drawer arranged under a desktop, an elbow supporting plate is hinged at the top horizontal edge of the inner face of the drawer&#39;s faceplate. Or alternatively, a left small drawer and a right small drawer are arranged under the desktop at the left side and at the right side respectively, a left elbow supporting plate and a right elbow supporting plate are hinged at the top of the inner faces of the left and right small drawer&#39;s lateral plates, with the inward arc edges opposite.

Description:
TECHNICAL FIELD 
       [0001]    This invention involves a kind of writing desk whose drawer connects with the arms support board. To be specific, it is mainly suitable for the writing desk in office and family. 
       TECHNICAL BACKGROUND 
       [0002]    As is well known, for the person who works bending over one&#39;s desk on the traditional writing desk for a long time, on one hand because a pair of elbows and forearms are supported on the rectangle desk panel to read and write, it must adopt the sitting posture of excessively leaning forward, which can cause the hunchback and eye myopia; on the other hand it makes the muscles of shoulder back, arm and wrist be in the tension condition for a long time because of hanging the elbow to operate the keyboard and mouse of the computer, thus causing the shoulder periarthritis, cervical spondylosis etc. 
         [0003]    In recent years, there has appeared the desk structure that there extends out the arms support board from the edge of desk panel close to one side of human body. The arms support board is that there are set up with one internal concave arc shaped gap slightly wider than the waist width of human body in the middle of traditional rectangle desktop. Both sides of internal concave shape protrude outwards oppositely. It is call as the arms support board. When the users carry on the desktop homework, their upper body above the waist enters the groove part by the desk, and the pair of elbows and forearms are supported on the arms support board of both sides. The arms support board is helpful for the users to correct the sitting posture, to decrease the fatigue, and makes the persons feel comfortable, and is beneficial to persons&#39; health. For example, patent of China, ZL89218825.1, ZL92200155.3, ZL97228199.1, they adopt the fixed type arms support board, simple structure, reliable, however, the occupied space of desktop increases, and it is inconvenient for the users to come in and go out; For example, patent of China, ZL99213798.5, ZL03239639.2, for the adopted turnover-downward foldable arms support board, the occupied space of desktop reduces, and it is convenient for the users to come in and go out. However, while turning over the arms support board, it needs to occupy the lower space of desktop. Thus it has limited the utilization of the lower space of the desk panel. For example, Place the drawer, the cupboard and the host case of computer, etc., in addition, it needs to add the supporting structure for the arms support board, and by doing so it can maintain the dependability of support of arms support board. In addition, because the keyboard of the computer is higher than the desktop, the wrist will not operate the keyboard unless upwarping it. The users can&#39;t support on the arms support board with a pair of elbows and forearms and operate the keyboard of the computer and turn over, write the files conveniently at one desk. 
       SUMMARY OF THE INVENTION 
       [0004]    The purpose of this invention is to improve the existing writing desk and to offer one a kind of writing desk whose drawer connects with the arms support board. Connect the arms support board to the top end of internal plate surface of opposite drawer side plate of left, right small drawers of writing desk with the hinge, or connect the left, right arms support board to the top end of internal plate surface of opposite drawer side plate of left, right small drawers of writing desk with the hinge. And it can turn over upwards by 180° and is supported on the top surface of drawer panel or drawer side plate. Through utilizing the function that the big drawers or two small drawers can be pushed and pulled under the desk panel of the writing desk, it can make the arms support board turn over to the usage status or hiding status after the big drawers or two small drawers are pulled out; And utilize the movable backing board connected to the upper surface of the arms support board to make a pair of elbow and forearm support on the arms support board or the movable backing board, and it is convenient not only to turn over and write the files but also to operate the keyboards and mice on the desk; It can also make the arms support board be inclined forward, and it can utilize the movable wedge-shaped backing board on the arms support board insert into between the arms support board and the inclined top surface of drawer panel to make the arms support board be in the horizontal status; In addition, it can also replace the drawer with the push-pull board. There can connect the arms support board with the hinge on the push-pull board. 
         [0005]    Technological Scheme Adopted in this Invention: 
         [0006]    A kind of writing desk whose drawer connects with the arms support board, there are set up with the big drawers that can be pushed and pulled under the desk panel of writing desk. There are set up with the arms support boards articulated with the side of long horizontal edge on the top end of internal plate surface of drawer panel of big drawer. The arms support board turns over upward and is supported on the top end of the drawer panel, and the upper surface of arms support board and the described desk panel are at the same height. 
         [0007]    A kind of writing desk whose drawer connects with the arms support board, there are set up with the small drawers that can be pushed and pulled at the left, right side of underside of desk panel of writing desk. There are set up with one piece of left arms support board and one piece of right arms support board at the top end of internal plate surface of opposite drawer side plate of left, right small drawers; the left, right arms support boards are opposite by the internal concave form arc shaped side and are articulated each other. The left arms support board and right arms support board turn over upward respectively and are supported on the top end of corresponding drawer side plate. And the upper surfaces of left, right arms support board and the described desk panel is at the same height. 
         [0008]    The upper surface of the described arms support board can be connected with one piece of movable backing board of shape same as the arms support board with the removable connecting parts; Or the upper surface of movable backing board and the described desk panel is at the same height. 
         [0009]    The top end of the described drawer panel is the inclined top surface of front end inclining downward. There are also set up with the one wedge-shaped block on the sliding guide at the rear of the described arms support board. 
         [0010]    For the top end of internal plate surface of drawer panel of described big drawer it can use the hinge that can turn over by 180° to connect the lateral surface of long horizontal side place of arms support board. 
         [0011]    The described arms support board is separated as one piece of left half arms support board and one piece of right half arms support board; and the long horizontal side of the arms support board is also divided into two sections and forms the concave groove shape together with the drawer panel. 
         [0012]    There are connected with one waling piece of corresponding length on the plate surface of long horizontal side of described arms support board. 
         [0013]    There are connected with one section of waling piece of corresponding length respectively on the plate surface of described two section of long horizontal side. 
         [0014]    There are set up with one keyboard tray inside the two pieces of drawer side plate of the described big drawer. 
         [0015]    The described big drawer is kind of push-pull board. 
         [0016]    There is all the vertical side at the left side of the described left arms support board and at the right side of the described right arms support board. It can use the hinge that can turn over by 180° to connect the vertical lateral surface of left, right arms support board at the to end of internal plate surface of opposite drawer side plate of described left, right small drawer. 
         [0017]    There are connected with one piece of vertical slab billet respectively on the plate surface of vertical side place of described left, right arms support board. 
         [0018]    The turnover of the arms support board of this invention does not occupy the lower space of drawer, and at the same time the user can support himself on the arms support board or movable backing plate with pairs of elbow and forearm at one desk to operate the computer keyboard or to turn over, write the file conveniently; Furthermore, it can make the arms support board be adapt to the need of horizontal desk panel and inclined desk panel, and the structure is simple and it is easy to use at the same time. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]      FIG. 1 : Local side section schematic diagram of the first embodiment of this invention 
           [0020]      FIG. 2 : Non-usage status schematic diagram for arms support board of the first embodiment of this invention 
           [0021]      FIG. 3 :  FIG. 2 : Usage status schematic diagram for arms support board of the first embodiment of this invention 
           [0022]      FIG. 4 : Non-usage status schematic diagram for arms support board of the second embodiment of this invention 
           [0023]      FIG. 5 : Usage status schematic diagram for arms support board of the second embodiment of this invention 
           [0024]      FIG. 6 : Non-usage status schematic diagram for arms support board of the third embodiment of this invention 
           [0025]      FIG. 7 : Usage status schematic diagram for arms support board of the third embodiment of this invention 
           [0026]      FIG. 8 : Non-usage status schematic diagram for arms support board of the fourth embodiment of this invention 
           [0027]      FIG. 9 : Usage status schematic diagram for arms support board of the fourth embodiment of this invention 
           [0028]      FIG. 10 : Non-usage status schematic diagram for arms support board of the fifth embodiment of this invention 
           [0029]      FIG. 11 : Usage status schematic diagram for arms support board of the fifth embodiment of this invention 
           [0030]      FIG. 12 : Local side section schematic diagram of the sixth embodiment of this invention 
           [0031]      FIG. 13 : Non-usage status schematic diagram for arms support board of the sixth embodiment of this invention 
           [0032]      FIG. 14 : Usage status schematic diagram for arms support board of the sixth embodiment of this invention 
           [0033]      FIG. 15 : Non-usage status schematic diagram for arms support board of the seventh embodiment of this invention 
           [0034]      FIG. 16 : Usage status schematic diagram for arms support board of the seventh embodiment of this invention 
           [0035]      FIG. 17 : Schematic diagram of status of computer keyboard of the eighth embodiment of this invention 
           [0036]      FIG. 18 : Schematic diagram of status of turning over and writing files of the eighth embodiment of this invention 
           [0037]      FIG. 19 : Horizontal schematic diagram of usage status for arms support board of the eighth embodiment of this invention 
           [0038]      FIG. 20 : Non-usage status schematic diagram for arms support board of the eighth embodiment of this invention 
           [0039]      FIG. 21 : Schematic diagram of status of operating the computer keyboard of the ninth embodiment of this invention 
           [0040]      FIG. 22 : Schematic diagram of status of turning over and writing files of the ninth embodiment of this invention 
           [0041]      FIG. 23 : Schematic diagram of inclining status of arms support board of the tenth embodiment of this invention 
           [0042]      FIG. 24 : Schematic diagram of horizontal status of arms support board of the tenth embodiment of this invention 
           [0043]      FIG. 25 : Local side sectional view when the arms support board of the tenth embodiment of this invention is not used 
           [0044]      FIG. 26 : Horizontal sectional view when the arms support board of the tenth embodiment of this invention is not used 
           [0045]      FIG. 27 : Schematic diagram of status of operating the computer keyboard of the eleventh embodiment of this invention 
           [0046]      FIG. 28 : Schematic diagram of status of turning over and writing files of the eleventh embodiment of this invention 
           [0047]      FIG. 29 : Side view schematic diagram of usage status for the arms support board, keyboard tray of the twelfth embodiment of this invention 
           [0048]      FIG. 30 : Top view schematic diagram of usage status for the arms support board, keyboard tray of the twelfth embodiment of this invention 
           [0049]      FIG. 31 : Schematic diagram of non-usage status for the keyboard tray of the twelfth embodiment of this invention 
           [0050]      FIG. 32 : Schematic diagram of usage status for the keyboard tray of the twelfth embodiment of this invention 
           [0051]      FIG. 33 : Upward view schematic diagram of the keyboard tray of the twelfth embodiment of this invention 
           [0052]      FIG. 34 : Front view schematic diagram of the keyboard tray of the twelfth embodiment of this invention 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0053]    The first embodiment of this invention is made out of one big drawer  1 , one supporting rack  2 , one piece of desk panel  3  and one piece of arms support board  4 , as shown in  FIGS. 1-3 , among them: 
         [0054]    The big drawer  1  is at the underside of desk panel  3  that is supported by the supporting rack  2  and it is in the face of the users of the sitting posture. And the big drawer  1  is on the longitudinal guide (not shown in the figure) set up under the at desk panel  3 , which can be pushed and pulled backwards and forwards along the orientation face to the users of sitting posture; The big drawer  1  is made out of one drawer panel  11 , two drawer side plate  12 , one drawer back plate  13  and one drawer bottom plate  14 . When provided for users to work, it can preserve or take out file, tool, etc. conveniently; the above mentioned belongs to the existing technology. 
         [0055]    The arms support board  4  is made out of the left, right vertical side edge of the desk panel, the front edge of two short horizontal edges and the rear edge of one long horizontal edge, and arc-shaped edge of middle part being internal concave form. And the arms support board  4  is connected to the top end position of internal plate surface of drawer panel  11  of big drawer  1  with the hinge (common hinge, or flat plate hinge, or bending hinge) at the side of the long horizontal edge position; When the users do not work, the arms support board  4  is in the big drawer  1 , and its upper plate surface and the top surface of drawer panel  11  are at the same horizontal plane. At this moment, two hinge surface of the hinge are combined together (i.e. its included angle close to 0°). When the users prepare to work, he pulls the big drawer  1  firstly, and opens the arms support board, namely turns over upward by 180° around the axial of the hinge. At this moment, one plate surface of the arms support board  4  is contacted with and is supported on the top surfaces of drawer panel  11 . Two hinge surfaces of the hinge are totally opened (i.e. its included angle close to 180°). Then push in the big drawer  1  to the underside of the desk panel  3  until the arms support board connects together with the desk panel. At this moment, the arms support board and the desk panel is at the same height, or slightly higher than the desk panel. In order to keep the stability at the, working position and to prevent the arms support board from disconnecting with the desk panel, it can add the positioning device among the arms support board, the big drawer and the writing desk, such as the inserted pin, positioning hook, the magnetism mass, the pressurize pit on the guide, etc. And then the users supports themselves by the pair of elbow and forearm on the arms support board  4 . The produced pressure and turn-over moment are borne by the hinge and the top surface of drawer panel  11 . Therefore, the supporting is stable and reliable; when the users stop working, he should turn over the arms support board  4  by 180° around the reverse direction above described to make it enter into the big drawer. Finally, push in the big drawer  1  at the underside of desk panel  3 ; it&#39;s evident that the turnover of the arms support board  4  does not occupy the lower space of the big drawer  1 . 
         [0056]    The second embodiment of this invention separates the arms support board from the left, right side of horizontal edge and appropriate to remove one section of middle part to form one piece of left half arms support board and one piece of right half arms support board. Their arc-shaped edge together with the drawer panel  11  form the concave groove part, as shown in  FIGS. 4 ,  5 ; Other structures are the same as first embodiment, and therefore no longer give unnecessary details repeatedly. 
         [0057]    For the third embodiment of this invention, there are connected with one waling piece  5  of corresponding length on the desk panel of long horizontal edge of arms support board  4 . Adjust the height difference between the desk panel  3  and the arms support board  4  with the thickness of this waling piece  5 , as shown in  FIGS. 6 ,  7 . It makes the desk panel  3  with the arms support board  4  form the suitable height difference in order to make the users&#39; wrist feel comfortable; other structures are the same as first embodiment, and therefore no longer give unnecessary details repeatedly. 
         [0058]    For the fourth embodiment of this invention, separate the arms support board  4  as left, right side and be appropriate to remove one section of middle part to form one piece of left half arms support board and one piece of right half arms support board. At this moment, one long horizontal edge of this arms support board  4  is also divided into two sections. There are connected with one section of waling piece  5  of corresponding length on the plate surfaces of two sections of long horizontal edge place respectively, as shown in  FIGS. 8 ,  9 ; Adjust the height difference between the desk panel  3  and the arms support board  4  with the thickness of this waling piece  5  to make the desk panel  3  and the arms support board  4  form the appropriate height difference in order to make the users&#39; wrist feel comfortable; Other structures are the same as first embodiment, and therefore no longer give unnecessary details repeatedly. 
         [0059]    For the fifth embodiment of this invention, there are set up with a pair of parallel guide  121  on the internal plate surface of two pieces of drawer side plate  12  of big drawer  1 . There are set up with one keyboard tray  122  of mutual sliding fit on the guide  121 , as shown in  FIGS. 10 ,  11 . The keyboard and mice of computer can be placed on the keyboard tray  122  in order to operate the computer placed on the desk panel  3  (not shown in the figure); But when the users work, it is unnecessary to push in the big drawer  1  to the underside of the desk panel  3  to make the arms support board with the desk panel connect together; Other structures are the same as first embodiment, and therefore no longer give unnecessary details repeatedly. 
         [0060]    The sixth embodiment of this invention is made out of two small drawers  1   a , one supporting rack  2 , one piece of desk panel  3  and two pieces of arms support boards  4   a ,  4   b , as shown in  FIGS. 12-14 , among them: 
         [0061]    The two small drawers  1   a  is at the underside of desk panel  3  that is supported by the supporting rack  2  and it is at the left, right side of the users of the sitting posture. And the two small drawers la is on the longitudinal guide (not shown in the figure) set up under the desk panel  3 , which can be pushed and pulled backwards and forwards along the both sides face to the users of sitting posture; The two small drawers  1   a  is made out of one drawer panel  11   a , two drawer side plate  12   a , one drawer back plate  13   a  and one drawer bottom plate  14   a . When provided for users to work, it can preserve or take out file, tool, etc. conveniently; the above mentioned belongs to the existing technology. 
         [0062]    The left arms support boards  4   a  is formed by the left vertical side edge of the plate surface, the short horizontal edge of front edge and the long horizontal edge of rear edge, and the internal concave form arc-shaped edge of right edge. While the right arms support boards  4   b  is formed by the right vertical side edge of the plate surface, the short horizontal edge of front edge and the long horizontal edge of rear edge, and the internal concave form arc-shaped edge of left edge. The left arms support boards  4   a  and the right arms support boards  4   b  oppositely form a concave groove shape by their internal concave form arc-shaped edge. And connect to the top end of internal plate surface of opposite internal drawer side plate  12   a  of left, right small drawers  1   a  with the hinge (common hinge, or flat plate hinge, or bending hinge) on their vertical side surfaces respectively; When the users do not work, the left arms support board  4   a  is inside the left small drawer  1   a  and the right arms support board  4   b  is inside the right small drawer  1   a . And their upper plate surface and the top surface of drawer side plate  12   a  are at the same horizontal plane. At this moment, two hinge surface of the hinge are combined together (i.e. its included angle close to 0°). When the users prepare to work, he should pull the two small drawers  1   a  open firstly, and turn over upward the left, right arms support board  4   a ,  4   b  by 180° around the axial of the hinge. At this moment, one plate surface of the left arms support board  4   a  and right arms support board  4   b  is contacted with and is supported on the top surfaces of the corresponding drawer side plate  12   a . At this moment, two hinge surfaces of the hinge are totally opened (i.e. its included angle close to 180°). Then push in the small drawer  1   a  to the underside of the desk panel  3  until the arms support board connects together with the desk panel. At this moment, the arms support board and the desk panel is at the same height, or slightly higher than the desk panel. In order to keep the stability at the working position and to prevent the arms support board from disconnecting with the desk panel, it can add the positioning device among the arms support board, the small drawer and the writing desk, such as the inserted pin, the positioning hook, the magnetism mass, the pressurize pit on the guide, etc. And then the users support themselves by the pair of elbow and forearm on the left, right arms support board  4   a ,  4   b . The produced pressure and turn-over moment are borne by the hinge and the top surface of drawer side plate  12   a . Therefore, the supporting is stable and reliable; when the users stop working he should turn over the left, right arms support board  4   a ,  4   b  by 180° around the reverse direction above described to make it enter into the small drawer  1   a . Finally, push in the small drawer  1   a  at the underside of desk panel  3 ; it&#39;s evident that the turnover of the left, right arms support board  4   a ,  4   b  does not occupy the lower space of the small drawer  1   a . 
         [0063]    For the seventh embodiment of this invention, there are respectively connected with one vertical plate slab  6  on the desk panel of vertical side edge of left arms support board  4   a  and right arms support board  4   b , as shown in  FIGS. 15 ,  16 . Adjust the height difference between the desk panel  3  and the left, right arms support board  4   a ,  4   b  with the thickness of this vertical plate slab  6  to make the desk panel  3  with the left, right arms support board  4   a ,  4   b  form the suitable height difference in order to make the users&#39; wrist feel comfortable; other structures are the same as sixth embodiment, and therefore no longer give unnecessary details repeatedly. 
         [0064]    The eighth embodiment of this invention is made out of one drawer  1   c , one supporting rack  2   c , one piece of desk panel  3   c , and one piece of arms support boards  4   c  and one movable backing board  5   c , as shown in  FIGS. 17-20 , among them: 
         [0065]    And the drawer  1   c  is on the longitudinal guide (not shown in the figure) set up under the desk panel  3   c , which can be pushed and pulled backwards and forwards along the sides face to the users of sitting posture; The drawer  1   c  is made out of one drawer panel  11   c , two drawer side plates, one drawer back plate and one drawer bottom plate. When provided for users to work, it can preserve or take out file, tool, etc. conveniently; the above mentioned belongs to the existing technology. 
         [0066]    The arms support board  4   c  is formed by the left, right vertical side edge of the desk panel, the two separated short horizontal edges of front edge and one long horizontal edge of rear edge, and arc-shaped edge of middle part being internal concave form. And the arms support board  4   c  is connected to the top end position of internal plate surface of drawer panel  11   c  of drawer  1   c  with the hinge (common hinge, or flat plate hinge, or bending hinge) at the side of the long horizontal edge position; When the users do not work, the arms support board  4   c  is inside the drawer  1   c , and its upper plate surface and the top surface of drawer panel  11   c  are at the same horizontal plane. At this moment, two hinge surfaces of the hinge are combined together (i.e. its included angle close to 0°). When the users prepare to work, he should pull the drawer  1   c  open firstly, and opens the arms support board, namely turns over upward the arms support board  4   c  by 180° around the axial of the hinge. At this moment, one plate surface of the arms support board  4   c  is contacted with and is supported on the top surfaces of drawer panel  11   c . Two hinge surfaces of the hinge are totally opened (i.e. its included angle close to 180°). Then push the drawer  1   c  towards the desk panel  3   c  until the arms support board  4   c  contact with the desk panel  3   c . At this moment, the upper surface of arms support board  4   c  and the desk panel  3   c  is at the same horizontal height, or slightly higher than the upper surface of desk panel  3   c . The desk can be regarded as the writing desk to be used at this moment. In order to keep the stability at the working position for the arms support board  4   c  and to prevent the arms support board from disconnecting with the desk panel, it can add the positioning device among the arms support board, the drawer and the writing desk, such as the inserted pin, positioning hook, the magnetism mass, the pressurize pit on the guide, etc. And then the users support themselves by the pair of elbow and forearm on the arms support board  4   c . The produced pressure and turn-over moment are borne by the hinge and the top surface of drawer panel  11   c . Therefore, the supporting is stable and reliable; when the users stop working, he should turn over the arms support board  4   c  by 180° around the reverse direction above described to make it enter into the drawer  1   c . Finally, push in the drawer  1   c  at the underside of desk panel  3   c ; it&#39;s evident that the turnover of the arms support board  4   c  does not occupy the lower space of the drawer  1   c.    
         [0067]    The movable backing board  5   c  is the board whose shape is roughly the same as that of the arms support board  4   c . Connect the movable backing board to the upper surface (i.e. the arms support board  4   c  is supported on the upper surface of top surface of drawer panel  11   c ) of arms support board  4   c  with the removable connecting parts (for instance: magnet, pin, snap fastener, etc.). It makes the upper surface of this movable backing board  5   c  be close to or slightly higher than the upper surface of computer keyboard  6   c  placed on the desk panel  3   c  in the horizontal height. At this moment the desk can be regarded as the computer desk to be used. When the pair of elbow and forearm of users are supported on the movable backing board  5   c  of the arms support board  4   c  to operate the computer keyboard  6   c , it has avoided needing to upwarp the wrist; Certainly, while turning over and writing the files, it can be very convenient to take down the movable backing board  5   c , a pair of elbows and forearms of users are supported on the arms support board  4   c  directly. In this way, one desk can act as computer desk and writing desk at the same time. 
         [0068]    For the ninth embodiment of this invention, there supports a keyboard tray  12   c  on the top surface of two pieces of drawer side plate of drawer  1   c  (the t keyboard ray  12   c  can also support on the a pair of guides parallel set up on the internal board surface of two pieces of drawer side plates). There are the computer keyboard  6   c  and mouse as well as wrist pad (with mouse pad) placing on the keyboard tray  12   c  (lead mouse cushion), and wrist cushion. The tray can carry out the push-pull backwards and forwards inside the drawer. Pull the drawer  1   c  open and open the arms support board  4   c . At this moment the upper surface of arms support board  4   c  is close to or slightly higher than the upper surface of computer keyboard  6   c  in the horizontal height, and the height is all lower than the lower surface of desk panel  3 C. The desk can be used as the computer desk at this moment. When the pair of elbow and forearm of users are supported on the arms support board  4   c  directly to operate the computer keyboard  6   c , it has avoided needing to upwarp the wrist; While turning over and writing the files, it can also be very convenient to fit on the movable backing board  5   c , then push the drawer  1   c  towards the desk panel  3   c  until the movable backing board  5   c  contact with the desk panel  3   c . It makes the upper surface of movable backing board  5   c  is the same as or slightly higher than the upper surface of desk panel  3   c . The desk can be used as the writing desk at this moment. The pair of elbow and forearm of users are supported on the movable backing board  5   c . As shown in  FIGS. 21 ,  22 ; other structures are the same as that of the eighth embodiment, and no longer give unnecessary details repeatedly. 
         [0069]    The tenth embodiment of this invention is made out of one drawer  1   d , one supporting rack  2   d , one piece of desk panel  3   d,  one piece of arms support boards  4   d  and one piece of wedge-shaped block  5   d , as shown in  FIGS. 23-26 , among them: 
         [0070]    The big drawer  1   d  is at the underside of desk panel  3   d  that is supported by the supporting rack  2   d  and it is in the face of the users of the sitting posture. And the big drawer  1   d  is on the longitudinal guide (not shown in the figure) set up under the at desk panel  3   d , which can be pushed and pulled backwards and forwards along the orientation face to the users of sitting posture; The desk panel  3   d  utilizes the scalable or foldable supporting that is supported by the back end of supporting rack  2   d  to make the desk panel  3   d  reach two kinds of states of horizontal and slope. When the drawer is provided for users to work, it can preserve or take out file, tool, etc. conveniently. There is one piece of drawer panel  11   d  in front of the drawer  1   d . The above mentioned all belongs to the existing technology; The top surface of this drawer panel  11   d  is the inclined top surface whose front end inclines downward by K°(approximately 12° or 24°). 
         [0071]    The arms support board  4   d  is formed by the left, right vertical side edge of the desk panel, the two separated short horizontal edges of front edge and the one long horizontal edge of rear edge, and arc-shaped edge of middle part being internal concave form. And the arms support board  4   d  is connected to the top end position of internal plate surface of drawer panel  11   d  of drawer  1   d  with the hinge (common hinge, or flat plate hinge, or bending hinge) at the side of the long horizontal edge position; When the users do not work, the arms support board  4   d  is inside the drawer  1   d . At this moment, two hinge surface of the hinge are combined together (i.e. its included angle close to 0°). 
         [0072]    When the users want to read, draw, it is necessary to adjust the desk panel  3   d  and the arms support board  4   d  to the sloping state. Pull the drawer  1   d  firstly and open the arms support board, namely turn over the arms support board  4   d  around the axial of the hinge (turn over by 180°+K°). At this moment, one plate surface of the arms support board  4   d  is contacted with and is supported on the inclined top surfaces of drawer panel  11   d . Then push in the drawer  1   d  to the underside of the desk panel  3   d  until the arms support board connects together with the desk panel. At this moment, the slope state of arms support board  4   d  and the desk panel  3   d  are probably identical, and the contact surface of the arms support board is the same as or slightly higher than the contact surface of the desk panel in the height. Accordingly the pair of elbow and forearm of users are supported on the arms support board  4   d  in order to satisfy the users&#39; need to read or draw; when the users stop working, he should turn over the arms support board  4  along the reverse direction above described to make it enter into the drawer  1   d . Finally, push in the drawer  1   d  at the underside of desk panel  3   d ; it&#39;s evident that the turnover of the arms support board  4   d  does not occupy the lower space of the drawer  1   d;    
         [0073]    The wedge-shaped block  5   d  is a triangular right prism body of acute angle K° (approximately 12° or 24°). It is connected to the back side of the arms support board  4   d  with the sliding guides (or with the axis of rotation perpendicular to the plate surface of the arms support board  4   d ). In order to ensure the wedge-shaped block  5   d  to be wedged tightly without loosen, there should be set up with the a set of elastic locating pin  6   d  at the back side of the arms support board  4   d , for example the locating pin is composed of the ball and the compression spring; 
         [0074]    When the users want to write, operate the computer keyboard and mouse, it is necessary to adjust the desk panel  3   d  and the arms support board  4   d  to the horizontal state. Lift the arms support board  4   d  with hand, and push on (or rotate around the vertical rotation axis) the wedge-shaped block  5   d  to reach the position between the arms support board  4   d  and the oblique top surface of drawer panel  11   d  to make the arms support board  4   d  and the desk panel  3   d  take on the state of equal height or slightly higher horizontal state. And the balls of the elastic locating pin  6   d  automatically lean against the end of the wedge-shaped block  5   d  under pressure of compression spring, support in order to prevent the wedge-shaped block  5   d  from loosing. 
         [0075]    The eleventh embodiment of this invention is to change one drawer  1   c  of the ninth embodiment into one piece of push-pull board  1   e  and cancel the keyboard tray, as shown in  FIGS. 27 ,  28 . The push-pull board  1   e  is at the underside of desk panel  3   e  that is supported by the supporting rack  2   e  and it is in the face of the users of sitting posture. And the push-pull board  1   e  is on the longitudinal guide set up under desk panel  3   e  (not shown in the figure), which can be pushed and pulled backwards and forwards along the orientation face to the users of sitting posture; The push-pull board  1   e  is made out of one piece of front end-plate  11   e  and one piece of horizontal plate  12   e  whose plate surfaces are perpendicular each other. It is used for placing the computer keyboard and mouse (with mouse pad) as well as the wrist pad, etc. when the users work. put of the (take the mouse cushion). Others are the same as that of the ninth embodiment. 
         [0076]    The twelfth embodiment of this invention is made out of one drawer  1   f , one supporting rack  2   f , one piece of desk panel  3   f , and one piece of arms support boards  4   f  and keyboard tray  5   f , as shown in  FIGS. 29-34 , among them: 
         [0077]    The drawer  1   f  is at the underside of desk panel  3   e  that is supported by the supporting rack  2   f  and it is in the face of the users of sitting posture. And the drawer  1   f  is on the longitudinal guide set up under desk panel  3   f  (not shown in the figure), which can be pushed and pulled backwards and forwards along the orientation face to the users of sitting posture; The drawer  1   f  is made out of one drawer panel  11   f , two drawer side plate  12   f , one drawer back plate  13   f  and one drawer bottom plate  14   f . When provided for users to work, it can preserve or take out file, tool, etc. conveniently. In addition there can be also all fixed a piece of plate slab on the internal plate surface of two drawer side plates  12   f . The above mentioned belongs to the existing technology. 
         [0078]    The arms support board  4  is formed by the left, right vertical side edge of the desk panel, the two separated short horizontal edges of front edge and the one long. horizontal edge of rear edge, and the arc-shaped edge of middle part being internal concave form. It can be allocated symmetrically at the left side and the right side of the arms support board and the width of right side can also be greater than that of left side so as to adapting to the persons who operate with right hand. While for the person who operate with left hand, it can be allocated contrary to it. The arms support board  4   f  is connected to the top end position of internal plate surface of drawer panel  11   f  of drawer  1   f  with the hinge (common hinge, or flat plate hinge, or bending hinge) at the side of long horizontal edge position; When the users do not work, the arms support board  4   f  is inside the big drawer  1   f , and its upper plate surface and the top surface of drawer panel  11   f  are at the same horizontal plane. At this moment, two hinge surfaces of the hinge are combined together (i.e. its included angle close to  0 °). When the users prepare to work, he should pull the drawer  1   f  open firstly, and open the arms support board, namely turns over the arms support board  4   f  upward by 180° around the axial of the hinge. Then push in the drawer  1   f  to the underside of the desk panel  3   f  until the arms support board  4   f  contacts together with the desk panel  3   f . At this moment, the arm support board or is the same as the height of the desk panel, or is slightly higher than the desk panel. At this moment, the desk can be used as the writing desk. In order to keep the stability at the working position for the arms support board and to prevent the arms support board from disconnecting with the desk panel, it can add the positioning device among the arms support board, the drawer and the writing desk, such as the inserted pin, the positioning hook, the magnetism mass, the pressurize pit on the guide, etc. And then the pair of elbow and forearm of users are supported on the arms support board  4   f . The produced pressure and turn-over moment are borne by the hinge and the top surface of drawer panel  11   f . Therefore, the supporting is stable and reliable; when the users stop working, he should turn over the arms support board  4  by  180 ° around the reverse direction above described to make it enter into the drawer  1   f . Finally, push in the drawer  1   f  to the underside of desk panel  3   f ; it&#39;s evident that the turnover of the arms support board  4   f  does not occupy the lower space of the drawer  1   f.    
         [0079]    There are the rectangle grooves on the upper surface of the keyboard tray  5   f , and the long edge of the rectangle groove is horizontal (there are the keyboard, wrist pad placing at the groove position, while there are the mouse placing on the upper surface of right side). There is fixed with one vertical baffle plate  51   f  at the left side of external bottom surface of keyboard tray  5   f , and there is set up with one detachable board  52   f  at its right side. There have two horizontal slots  521   f  on the detachable board  52   f , and there are connected with one vertical baffle plate  522   f  of longitudinal stretching downwards in the middle of two horizontal slots  521   f . And connect the detachable board  52   f  to the external bottom surface of the keyboard tray  52   f  with the bolt. For the keyboard tray  5   f , the vertical baffle plate  51   f , the vertical baffle plate  522   f  of stretching downwards (if the bolt is connected at left end head of horizontal trough hole  521   f ) are leaned against the interior of two drawer side plates  12   f  of drawer  1   f  respectively. While the external bottom surface of the keyboard tray  5   f  is supported on the top surface of two drawer side plates  12   f  (can also attain the purpose through the method that the external bottom surface of the keyboard tray  5   f  is supported on the plate slab of internal plate surface of two drawer side plates  12   f  of drawer  1   f ). It makes the height of each key of computer keyboard that is placed inside the keyboard tray  5   f  is the same as or is close to the height of upper plate surface of the arms support board  4   f . The desk can be used as computer desk at this moment, as shown in  FIG. 32 . It avoids that operator can operate the keys only in the upwarping posture for the wrists of them; In case of not needing to use the keyboard, mouse, it can connect the bolt to the right end of horizontal slot  521   f . At this moment, the keyboard tray  5   f  can be put on the drawer bottom plate  14   f  inside the drawer  1   f  directly, as shown in  FIG. 31 . The notebook computers can also be placed at the groove position of keyboard tray.