Abstract:
A top plate is supported while being greatly projected forward of leg bodies, which forms a large lower leg space under the top plate. Upper ends of left and right leg bodies ( 2 ) having, at their lower ends, base legs ( 2   a ) that are directed in a front-rear direction are connected by lateral connection rods ( 3 ) that are directed in a left-right direction and have a non-circular cross-section. Rear end sections of at least a left and right pair of top plate support bodies ( 4 ) directed in the front-rear direction are fixed to the lateral connection rods ( 3 ) so as to project forward. The lower surface of the top plate ( 26 ) is installed on the top plate support bodies ( 4 ) such that the most part of the top plate ( 26 ) is located forward of the lateral connection rods ( 3 ).

Description:
[0001]     This application is a national stage completion of PCT/JP2005/018432 filed Oct. 5, 2005 which claims priority from Japanese Application Serial No. 2004-292590 filed Oct. 5, 2004, which claims priority from Japanese Application Serial No. 2004-292594 filed Oct. 5, 2004, which claims priority from Japanese Application Serial No. 2005-228298 filed Aug. 5, 2005.  
       TECHNICAL FIELD  
       [0002]     The present invention relates to a table suitable to operate office automation equipment such as a personal computer.  
       BACKGROUND OF THE INVENTION  
       [0003]     A known table comprises a pair of inverse T- shaped, I-shaped or gate-like legs; a lateral cross beam connecting the legs to each other a top supported by the legs.  
         [0004]     JP5-228028A discloses that a pair of legs is coupled to each other at the rear end with a cross beam and that the lower surface of the top is supported by a pair of supports of the legs.  
         [0005]     JP3-30021Y2 discloses that an auxiliary top on which a key board thereon is mounted to a pair of legs with a parallel link to allow the auxiliary top to move horizontally between an operating position in front of the main top and an inoperative position in which it is stored under the main top.  
         [0006]     A desk or a table having an operating device is described in JP4-53694Y and JP2001-128741A.  
         [0007]     JP62-49807A discloses a device that comprises a parallel link for supporting a moving member; a locking unit supported by the parallel link to lock an angle of the moving member with a frictional force; and a force-promoting unit mounted between a leg and the moving member to assist up-and-down motion and rotation of the moving member, rotation of the parallel link enabling the moving member to go up and down, releasing of the unlocking unit enabling the angle of the moving member to vary.  
         [0008]     In an ordinary table or the table in JP5-228028A, the lower surface of the top is supported by a pair of legs directly, so that the depth of the top is limited not to enable a leg space to be produced under the top.  
         [0009]     Thus, when a person operates a key board on the top in an easy posture in which one&#39;s legs deeply extend under the top, a chair or one&#39;s leg of the person becomes closer to the legs of the table, so that relaxed feeling cannot be achieved.  
         [0010]     It is not possible to adjust the height and angle of the top, so that the person cannot operate the key board at suitable posture.  
         [0011]     In the table in JP3-30021Y, the auxiliary top can be situated in front of the main top to avoid the former disadvantages. But, when the auxiliary top is stored under the main top, it makes it difficult to work in front of a table.  
         [0012]     The auxiliary top is horizontal in use, and is not adjustable on its angle.  
         [0013]     As well as the above, it is not possible to operate a key board suitably.  
         [0014]     In the operating device in JP4-53964Y and JP2001-128741A, an operating lever or portion for adjusting a height of a top is provided at each side of the lower surface of the front end of the top and pulled to allow a height of the top to be adjusted. Thus, it is difficult to operate the lever in a posture where one&#39;s legs are deeply placed under the top while one still sits on the chair.  
         [0015]     JP4-53694Y discloses that there is an opening at the lower surface of the front end of the top. An operating lever is provided in the opening thereby making it difficult to put a hand into the opening.  
         [0016]     The operating portion in JP2001-128741A projects from the lower surface of the top thereby making its appearance worse. One&#39;s knee is likely to strike the operating portion.  
         [0017]     In JP6249807A, the moving member by the parallel link or a support point for the top and a connecting point between the force-promoting unit and the top are provided on the front part of the top to make the support of the top unstable. If a heavy object is put on the rear part of the top, greater moment is applied to the support point of the top to let the top inclined downwards. The end of the parallel link is likely to be damaged.  
       SUMMARY OF THE INVENTION  
       [0018]     In view of the disadvantages in the prior art, it is an object of the present invention to solve the problems below:  
         [0019]     (A) to provide a table in which a greater leg space is formed under the top by supporting the top that projects from the leg of the table greatly to achieve feeling of freedom when one&#39;s leg is deeply put under the top and to adjust height and angle of the top suitably depending on its use:  
         [0020]     (B) to provide an operating unit for actuating a gas spring to enable it to be operated easily while one still sit on a chair to improve operativity and appearance; and  
         [0021]     (C) to provide a table in which the top is stably supported and is easily changed on an angle easily and naturally, a greater space being formed under the top. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0022]      FIG. 1  is a perspective view of one embodiment of a table according to the present invention;  
         [0023]      FIG. 2  is a perspective view of a support frame of the table;  
         [0024]      FIG. 3  is an enlarged vertical sectional side view taken along the line III-III in  FIG. 2 ;  
         [0025]      FIG. 4  is a central vertical sectional side view of a support for a top when the top is horizontal;  
         [0026]      FIG. 5  is a central vertical sectional view of the support for the top when the top is tilted forwards;  
         [0027]      FIG. 6  is a side view when a side table is removed;  
         [0028]      FIG. 7  is a side view when the top rises.  
         [0029]      FIG. 8  is a top plan view of a parallel-link mounting potion and an operating unit for a gas spring;  
         [0030]      FIG. 9  is an enlarged vertical sectional side view taken along the line IX-IX in  FIG. 8 ;  
         [0031]      FIG. 10  is an enlarged vertical sectional view taken along the line X-X in  FIG. 8 ;  
         [0032]      FIG. 11  is a vertical sectional side view of a support pole mounting portion;  
         [0033]      FIG. 12  is a vertical sectional side view of a subsidiary top mounting portion; and  
         [0034]      FIG. 13  is a side elevational view of a side table. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0035]      FIG. 1  is a perspective view of a table for operating office automation equipment according to the present invention, and  FIG. 2  is a perspective view of a support frame for the table.  
         [0036]     The support frame  1  comprises a pair of legs  2 , 2  in parallel; a pair of cross beams  3 , 3  in parallel for connecting the legs  2  to each other; and a top support  4  in front of the middle of the cross beams  3 , 3 .  
         [0037]     The leg  2  comprises a leg base  2   a  and a leg post  2   b  having an elliptical cross-section. At the upper end of the leg post  2   b , a support member  5  is fixed to support each end of the cross beam  3 .  
         [0038]     In  FIG. 3 , the cross beam  3  is made of Al alloy having a hexagonal cross-section and has a pair of vertical-plate reinforcement ribs  6 , 6  in parallel.  
         [0039]     An opening at each end of the cross beam  3  is closed by an end cap  7 .  
         [0040]     In  FIG. 3 , the support member  5  comprises a support plate  5   a  which has a groove  8  in which a lower half of the cross beam fits; and a holding plate  5   b  which has a groove  9  in which an upper half of the cross beam  3  fits.  
         [0041]     After each end of the cross beam  3  fits in the grooves  8 , 8  of the support plates  5   a , the upper half is covered with the groove  9  of the holding plate  5   b.    
         [0042]     A bolt  10  passes through the middle of the support plate  5   a  and the holding plate  5   b  and is engaged in a female thread  12  at the upper end of a tube  11  in the hollow leg post  2   b . Two bolts  13  which pass through the holding plate  5   b  are engaged in female threads  14  to allow the leg post  2   b  and the support member  5  to be fixed with each end of the cross beam  3  firmly.  
         [0043]     When the holding plate  5   b  is tightened over the support plate  13  with the bolts  10 , 13 , a slight gap is formed to allow each end of the cross beam  3  to be fastened tightly with the support member  5 .  
         [0044]     The hexagonal cross-section of the cross beam  3  which horizontal upper and lower surfaces allows the height of the support member  5  to become smaller thereby improving appearance, facilitating mounting of optional parts (later described) and positioning the support member  5  easily in a horizontal direction.  
         [0045]     The six outer peripheral surfaces of the cross beam  3  is firmly fixed by the support member  5  to prevent the support member  5  from rotating on its own axis or from loosening.  
         [0046]     Furthermore, a pair of reinforcement ribs  6  are provided within the cross beam  3  to prevent the cross beam  3  from bending down or being twisted.  
         [0047]     The cross-section of the cross beam  8  may be an octagon which has horizontal upper and lower surfaces, other polygon or other noncircular shape.  
         [0048]     The top support  4  comprises a pair of support members or support brackets  15 , 15  mounted to the connecting member  3 ; and a pair of parallel links  16 , 16  pivotally mounted to the front ends of the support brackets  15 , 15 .  
         [0049]     The support bracket  15  is smaller in width than the support member  5  and has grooves (not shown) in an upper support plate  15   a  and a lower holding plate  15   b  engaging on the upper and lower halves of the cross beam  3 . The support bracket  15  is firmly fixed to the cross beam  3  with bolts  10 , 13  in  FIG. 3 .  
         [0050]     In  FIGS. 4-8 , the parallel link  16  comprises a shaft  18   a  which passes through a rectangular bar  18  which connects bearings  17 , 17  to each other at the front ends of the upper holding plate  15   b  of the support brackets  15 ; the first link arm  19  which engages at the rear end with outer projecting ends of the shaft  18   a ; the second link arm  22  which is upper than the first link arm  19  and pivotally secured with a pivot  21  to an upward projection  20  of the holding plate  15   b ; an up-and-down member  23  pivotally secured to the front ends of the first and second link arms  19 , 22  with shafts  23   a , 23   b ; and a connecting member  24  which connects the up-and-down objects  23 , 23  to each other.  
         [0051]     The front end of the second link arm  22  is positioned by putting in a groove  23   c  at the rear end of up-and-down object  23 . The front end of the second link arm  22 , the up-and-down object  23  and the connecting member  24  are connected with the shaft  23   b.    
         [0052]     The upper front end of the up-and-down object  23  is pivotally secured to the front end of the top support arm  25  fixed to the lower surface of the top  26  with a shaft  25   a  in front of the center G of gravity of the top  20 .  
         [0053]     The top  26  is a reverse trapezoid in a top plan view having an inward-curved front end and an outward-curved rear end and has a hand-putting part  26   a  made of slightly-soft elastomer resin  26   a.    
         [0054]     The outer periphery of the hand-putting part  26   a  has a lower inclined surface to reduce its thickness in  FIG. 10 .  
         [0055]     Owing to such shape of the top  26 , the center G of gravity is positioned behind the center of the top  26  to allow the top  26  to be supported stably even when the top  26  extends from the leg  2  greatly. The top  26  is positioned to surround a user to make its use advantageous especially when one operates a lot of office automation equipment on the top  26 .  
         [0056]     The parallel links  16 , 16  are mounted to the front ends of the support brackets  15 , 15  fixed to the front and rear cross beams  3  to allow the top  26  to be supported by the top support arms  25 , 25  pivotally secured to the front end, thereby enabling the top  26  to be mounted, while the top  26  projects forwards from the leg post  2   b  and the cross beam  3 .  
         [0057]     Thus, under the top  26 , a great space is created to enable the user to operate a key board on the top  26  in a relaxed posture where one&#39;s leg is placed deeply under the top  26 .  
         [0058]     Furthermore, the second link arm  22  of the parallel link  16  is higher than the first link arm  19 . Between the right and left second link arms  22 , a leg space is formed. A finger or clothes are not likely to be held between the first and second link arms  19  ands  22 .  
         [0059]     The right-and-left parallel links  16  and  16  are connected to each other with the cross beams  18 , 24  to enable the parallel links  16 , 16  to turn synchronously.  
         [0060]     The front and rear cross beams provide high strength against bending or twisting as mentioned above. Thus, even when the top  26  which projects forwards is supported, disadvantages are not likely to occur, so that the weight of the top  26  is borne surely and stably.  
         [0061]     Loosening the bolts for the support bracket  15  enables mounting positions of the parallel links  16  and the top  26  to change horizontally.  
         [0062]     In the middle of the cross beam  24  and the cross beam  18 , the first hydraulic locking gas spring  27  for adjusting height is pivotally secured at the front end to the cross beam  24  and at the rear end to the cross beam  18  via U-shaped brackets  28 , 28  to apply upward force when the top  26  is moved up and down by the parallel links  16 .  
         [0063]     In the middle of the top  24  and in a recess  26   b  of the lower surface of the top  26 , the second hydraulic gas spring  29  with a lock for tilting the top  26  is pivotally secured via U-shaped brackets  28 , 28  to apply upward force when the top  26  is tilted down forwards.  
         [0064]     In  FIGS. 4 and 9 , in the first and second gas springs  27 , 29  (only the first gas spring the same as the second one is shown), a valve  27   b  which projects from the front end of the piston rod  27   a  is pressed by the lower end of an operating lever  31  pivotally secured to a connector  30  which connects the piston rod  27   a  to the bracket  28  to allow them to be unlocked to enable the piston rod  27   a  to project by internal gas pressure.  
         [0065]     The upper end of the operating lever  31  is coupled to one end of a wire  33   a  passing through an outer cable  33  coupled to a support piece  32  of the connector  30 .  
         [0066]     In  FIGS. 8 and 10 , at the front inner corners on the lower surface of the hand-putting portion  26   a  of the top  26 , there are hydraulic unlocking units  34 , 34  in which the outer cables  33  for the first and second gas springs  27 , 29  are coupled to the other ends of the wires  33   a.    
         [0067]     The two unlocking units  34 , 34  are symmetrical and comprise the same structure, and only the right-side unlocking unit  34  will be described.  
         [0068]     The unlocking unit  34  fits in a recess  35  in the lower surface of the hand-putting portion  26   a , and comprises a U-shaped support base  36  in which a peripheral portion  36   a  is bolted to the lower surface of the top  26 ; an operating lever  37  received in a recess  36   b  of the support base  36 ; and a cover plate  38  which covers an opening surface of the upper end of the support base  36 .  
         [0069]     The recess  36   b  of the support base  36  is substantially elliptical and has a straight line at the rear end. The rear part of the bottom surface is open.  
         [0070]     A pivot  40  projects from the upper surface of the front part of the recess  36   b.    
         [0071]     The operating lever  37  is elliptical and is slightly narrower than the recess  36   b  of the support base  36 . A pivotal tube  41  which projects downwards at the front part fits on the pivot  40  of the support base  36  to allow the operating lever  37  to turn horizontally around the pivot  40  in the recess  37 .  
         [0072]     Over the opening  39  of the support base  36  at the rear part of the operating lever  37 , a hand-engaging portion  43  is surrounded by a rectangular frame  42 .  
         [0073]     On the upper surface of a groove of a downward projection  44  of the operating lever  37 , an engagement projection  45  projects to engage with the wire  33   a.    
         [0074]     The other end of the outer cable  33  is secured to a holding portion  46  which projects inwards from the inner side surface of the support base  36 . The other end of the wire  33   a  which projects from the outer cable  33  is coupled to the operating lever  37  by mounting a washier  47  to the engagement projection  45  with a screw  48 .  
         [0075]     The front side edge of the top  26  is held by a hand. A thumb of the hand is placed on the top  26 , while the other four fingers are inserted in the hand-engaging recess  43  of the operating lever  37 . The four fingers are pulled outwards horizontally to allow the operating lever  37  to turn outwards horizontally around the pivot  40 , so that the wire  33   a  is pulled.  
         [0076]     Thus, the operating lever  31  is rotated to press the valve  27   b  to allow the first gas spring  27  to become free.  
         [0077]     The top  26  applied by the upward force by the gas spring  27  can be moved up and down freely by turning the parallel link  16  up and down.  
         [0078]     Taking one&#39;s hand off the operating lever  37  at an optional position allows the first gas spring to be locked in  FIGS. 6 and 7 , so that the height of the top  26  is adjusted.  
         [0079]     If the top  26  is heavy, a supplemental forcing unit (not shown) such as a torsion coil spring may be provided between the cross beam  18  of the parallel link  16  and the first link arm  19  not to cause the top  26  to move down by its own weight when the first gas spring  27  is unlocked.  
         [0080]     When the left-side operating unit  34  is operated as well, the second gas spring  29  is unlocked to become free to allow the top  26  to turn up and down around a pivot of the top support arm  25 . Releasing the operating lever  37  at an optional position makes the second gas spring  29  locked, so that the top  26  is adjusted at a desired tilted position in  FIG. 6 .  
         [0081]     As mentioned above, the top  26  comprises a reversed trapezoid. The operating units  34 , 34  for actuating the first and second gas springs  27 , 29  are provided on the lower surface of the inner front corners along the same direction as the side end face of the hand-engaging portion  26   a  and can be turned horizontally in a forwardly-inclined direction to allow both hands of a sitting person to become closer to the right-and-left operating units  34 , 34 , so that one can easily turn the right-and-left operating levers  37 , 37  by both hands while one is still sitting.  
         [0082]     When one grasps the front corner of the top  26 , the four fingers other than the thumb naturally touch the operating lever  37  enabling the height and angle of the top  26  to be adjusted together with operation of the operating lever  37 .  
         [0083]     In  FIGS. 1, 6  and  7 , the front and rear cross beams  3 , 3  may include two support poles  50 , 50  and an auxiliary top  51  which will be mounted below.  
         [0084]     In  FIGS. 11 and 12 , a mounting member  52  for mounting the support pole  50  and the auxiliary top  51  comprises a pair of fixing plates  52   a , 52   b  which have grooves  53 , 53  in which upper and lower halves of the cross beam  3  fit respectively. The upper fixing plate  52   a  of the fixing member  52  includes grooves  55 , 55  at the upper rear surface. The lower ends of the support pole  50  and a strut  54  for the auxiliary top  51  fit in the grooves  55 , 55  respectively.  
         [0085]     After the cross beam  3  fits in the grooves  53  of the upper and lower fixing plates  52   a , 52   b , a bolt  56  which passes through the upper fixing plate  52   a  engages with a female thread bore  57  of the lower fixing plate  52   b . A bolt  58  which passes through the rear parts of the upper and lower fixing plates  52   a a, 52   b  is screwed in a female thread bores  59  at the lower ends of the support pole  50  and strut  54  the lower ends of which fit in the grooves  55 . By tightening the bolt  58 , the mounting member  52  is firmly fastened to the front or rear cross beam  3 , and the support pole  50  and the strut  54  are fastened on the mounting member  52 .  
         [0086]     To fasten the support member  52  to the cross beam  3 , a slight gap for a tightening region is formed between the upper and lower fixing plates  52   a  and  52   b.    
         [0087]     As shown by dotted lines in  FIGS. 11 and 12 , the depth of the mounting member  52  is determined such that the rear end of the front mounting member  52  does not touch the rear cross beam  3  when the mounting member  52  is fastened to the front mounting member  52 .  
         [0088]     To the upper end of the strut  54 , the lower surface of the auxiliary top  51  is mounted by fastening a bracket  60  fixed to the strut  54  with a plurality of screws  61 .  
         [0089]     In  FIG. 6 , a display for a personal computer can be mounted to the support pole  50  or the auxiliary top  51  so that its height can be adjusted.  
         [0090]     As shown by dotted lines in  FIG. 12 , the mounting member  52  is fastened to the front cross beam  3 , so that the auxiliary top  51  is located at the front side, so that it can be approached to the top  26  thereby allowing the user to watch the display D more easily.  
         [0091]     The mounting member  52  may be fastened to the rear cross beam  3  by reversing the mounting member  52  by 180 degrees, so that the auxiliary top  51  can be located forward. In such a location, the support pole  50  may be removed.  
         [0092]     The cross beam  3  extends through the mounting member  52 . So by loosening the bolts  56 , 58 , the mounting position can be optionally changed right and left.  
         [0093]     The cross beam  3  has a hexagonal cross-section which enables mounting strength of the mounting member  52  to become greater. The mounting member  52  is fastened to only one cross beam  3  to enable the load of the display D to be supported enough. To bear greater load, the mounting member  52  has a cross-section in  FIG. 3  and may hold the front and rear cross beams  3 .  
         [0094]     In  FIGS. 1 and 13 , on the upper surface of the support member  5  fixed to the upper ends of the right-and left legs  2 , a subsidiary top  63  of a rectangular side table  62  is pivotally mounted sideward in a horizontal direction.  
         [0095]     The side table  62  is longer than the top  26 .  
         [0096]     In the middle of the upper holding plate  5   b  of the support member  5 , two bores  64  are formed and a screw  65  is inserted into the bore  64  before the holding plate  5   b  is fastened to the lower support plate  5   a . The upper part of the screw  65  is engaged though a female thread bore (not shown) at the lower end of a fastening rod  67  projecting from the lower surface of a support base plate  66  to allow the support base plate  66  to be fastened horizontally slightly above the support member  5 .  
         [0097]     Then, on the upper surface of the support base plate  66 , a known rotary support unit  68  which comprises a fastening base  68   a  and a rotary plate  68   b  disposed rotatably via a number of balls (not shown) is mounted by screwing the fastening base  68   a.    
         [0098]     By screwing the rotary plate  68   b  to the middle of the lower surface of the rear end of the subsidiary top  63 , the side table  62  can be horizontally pivoted around the support member  5  by the top  26 .  
         [0099]     The middle of the lower surface of the front part of the subsidiary top  63  is fixed to the upper end of a support leg  70  which has a height adjuster  69  at the lower end.  
         [0100]     In  FIG. 1 , the inner side end of the subsidiary top  63  is curved outwards at almost equal curvature as the outer side end of the top  26  so that they become closer to or are in contact with each other when the top  63  turns at the maximum.  
         [0101]     When the subsidiary top  63  turns at the maximum, the front end of the subsidiary top  63  becomes continuous almost like arc with the front end of the top  26 .  
         [0102]     As mentioned above, the subsidiary top  63  of the side table  63  is pivotally mounted sideward in a horizontal direction to the upper end of the leg post  2   b  of the leg  2  or the upper surface of the support member  5  at the side of the top  26  thereby enabling the right-and left subsidiary tops  63  to turn independently and become greater at a turning area.  
         [0103]     Specifically, the right-and-left subsidiary tops  63  are allowed to turn greatly sideward to enable the side table  62  to become longer in a right-and-left direction, so that a plurality of persons can use them as working table.  
         [0104]     The subsidiary top  63  is turned inwards to the maximum position and the upper surface of the top  26  is made horizontal and coplanar with the upper surface of the subsidiary top  63  thereby forming a continuous greater top surface, so that larger operation area can be created and location area for office automation equipment can be expanded.  
         [0105]     The present invention is not limited to the foregoing embodiments.  
         [0106]     In the foregoing embodiment, the top support  4  for supporting the top  26  or a pair of parallel links  16  is provided in the middle of the cross beam  3  connecting the legs  2  and  2  to each other via the support bracket  15 . But, to extend the length of the top  26  without the side table  62 , the top support  4  may be provided to the support member  5  fixed to the upper end of the leg post  2   b.    
         [0107]     If it is not required to adjust the height and angle of the top  26 , the parallel links  16  and gas springs  27 , 29  may be omitted. Instead, the support brackets  15  and top support fixed thereto may be projected forwards and the lower surface of the top  26  may be directly mounted thereto.  
         [0108]     In the foregoing embodiments, the support base  36  is engaged in the recess  35  at the front corner of the lower surface of the top  26  and the operating lever  37  is received in the recess. But without the support base  36 , the support lever  37  is pivotally secured in the recess via a vertical pivot directly.  
         [0109]     To enable one of the height and angle of the top  26  to be adjusted, the operating unit  24  may be provided at one of right-and-left sides.  
         [0110]     Furthermore, without the gas spring  27  for raising the parallel links  16  and stopping rotation thereof, a suitable stopper may be provided to stop the top  26  at the lower and upper limits.