Abstract:
A classroom desk is provided at a low cost which does not restrict a positioning angle of a computer display and offers an unobstructed front view when a movable top panel is open. The classroom desk is suitable for a class requiring the occasional use of a small-sized computer. The desk comprises a fixed top panel on which the computer is mounted, and movable top panel which covers and hides the computer. The movable top panel is connected to the fixed top panel by first and second link members and is arranged to stand vertically at the back of the desk in such a manner that about half of a depth of the movable top panel is located below the height of the fixed top panel.

Description:
FIELD OF THE INVENTION  
       [0001]     This invention relates to a desk for classroom use in which a small-sized computer may be mounted at all times.  
       BACKGROUND OF THE INVENTION  
       [0002]     Along with the spread of small-sized computers, many schools have introduced classes using small-sized computers, and classroom desks in which small-sized computers, such as laptops, are disposed.  
         [0003]     Japanese Design Registration No. 1094712 illustrates a first example of such classroom desks. The desk is provided with a movable top panel which covers and hides a small-sized computer located on the desktop. In classes requiring the use of the computer, one can simply swing open the movable top panel to unhide the computer.  
         [0004]     Japanese Utility Model No. 2555572 discloses a second example of this type of classroom desk. In this example, while open, the movable top panel can be stored vertically in a back space of the desk.  
         [0005]     In the desk of the first example as shown in  FIG. 5 , a movable top panel  21  is swingably attached to the back end of a fixed top panel  22  on which a small-sized computer  30  is disposed. When the computer  30  is intended to be used, the movable top panel  21  is rotated open. In classes not requiring the use of the computer  30 , the movable top panel  21  is shut so that the top surface of the movable top panel  21  can be used as a desktop. Reference number  21   a  indicates a side panel which delimits and screens a space between the movable top panel  21  and the fixed top panel  22  when the movable top panel  21  is in a closed state.  
         [0006]     In the desk of the second example, as shown in  FIG. 6 , a back end of a movable top panel  25  is connected to a connection panel  29  such that the movable top panel  25  can be rotated vertically. The connection panel  29  is engaged with a slide  27  which slides in a vertical direction. When opening the desk, the movable top panel  25  initially stands vertically and then slides downward by its own weight to be automatically stored in a back space of the desk. To restore the movable top panel  25 , one can vertically lift up the panel  25  by hand and then rotate the panel  25  down to the front. Reference number  28  indicates a constant load spring.  
       SUMMARY OF THE INVENTION  
       [0007]     The classroom desk of the first example has a simple structure which can be produced at a low cost. Also, such a desk does not require much space for installation. However, the movable top panel in an open state may only be raised to an angle of about  80  degrees at most, relative to the fixed top panel. Consequently, the standing angle of the computer display may be limited. A user is not able to freely adjust the angle of the computer display. Moreover, the open movable top panel is located at a higher position than the computer display. As a result, the panel gets in the way of one&#39;s front view. Communication between a lecturer and a participant may be hindered.  
         [0008]     On the other hand, in case of the classroom desk of the second example, the computer display can be raised to any desired angle. Also, one&#39;s front view is not blocked since the movable top panel is stored in the back space of the desk. However, it is necessary to provide mechanisms for sliding as well as for preventing the falling of the movable top panel. Thus, the desk may be expensive and require a significant amount of space for installation. Moreover, opening and closing of the movable top panel is more difficult to accomplish as compared to the movable top panel of the first example. This type of desk is not suitable for classes which require frequent openings and closings of the movable top panel.  
         [0009]     One object of the present invention is to provide a classroom desk which removes significant restrictions from the standing angle of a computer display and provides an unobstructed front view when the movable top panel is open.  
         [0010]     To attain this and other objects, the present invention provides a classroom desk comprising two top panels. One top panel is a fixed top panel on which a small-sized computer is mounted. Another top panel is a movable top panel which covers and hides the computer mounted on the fixed top panel. The top surface of the movable top panel can be used as a desktop when the computer is not being used. Support blocks are provided on the right and left sides along a back portion of the desk. The movable top panel is connected to each support block by means of two link members, which constitutes a four-point link structure. The movable top panel in an open state stands vertically in such a manner at the back of the desk that about half of the depth of the movable top panel is located below the height of the fixed top panel.  
         [0011]     The small-sized computer herein may mean a notebook computer, a laptop computer, or other electronic device, whose display portion can be opened and closed so as to generally function as a lid for the computer.  
         [0012]     The fixed top panel of the desk herein is normally extended in the lateral direction so that two or three persons can comfortably sit in front of the desk, side by side. However, the present invention can be also applied to a desk for use by other numbers of users, such as one, two, or four persons.  
         [0013]     The movable top panel in an open state is arranged to stand vertically in such a manner that about half of the depth thereof is located below the height of the fixed top panel. However, it is not necessary to be strictly limited by the above embodiment. Any arrangement configuring the depth of the opened movable top panel is acceptable as far as the computer display can be raised to not less than 90 degrees and the movable top panel is positioned lower than an upper end of the computer display (i.e., a position that does not significantly interfere with the front vision of a user).  
         [0014]     The movable top panel is swingably connected to the support blocks, secured to the right and left sides of the back portion of the fixed top panel, by a four-point link structure. The support blocks are made compact so that a user can enjoy as large a space as possible on the top surface of the fixed top panel when the movable top panel is in an opened state. The upper surface of the support block is flat so as to support the movable top panel when the movable top panel is in a closed state.  
         [0015]     The link member is provided with a spring which can urge the movable top panel toward an opened state, so that even if the movable top panel is prematurely released at the time of closing, the movable top panel does not bang shut. It is preferable that one of the link members connected to each support block, particularly the link member positioned at the rear side of the movable top panel, is rotatably connected to a shaft which is supported by a bearing attached to each support block. It is also preferable that a rotary damper is provided to dampen or restrict the forward and backward rotations of the shaft. Then, in addition to the inadvertent dropping of the movable top panel at the time of closing, the rebounding of the movable top panel during an abrupt opening can also be avoided.  
         [0016]     It is necessary to safely store the small-sized computer when no one is in the classroom so that the computer may not be stolen or played with. It is preferable that any space between the movable top panel and the fixed panel is securely screened while the movable top panel is closed, and that a locking mechanism is provided with the desk. However, it may be unreasonably annoying if each participant had to perform the locking and unlocking of their corresponding desk.  
         [0017]     Therefore, it is preferable that a side panel at the right and left end portions and a front panel at the front end portion are respectively provided on the underside of the movable top panel. Also, a back panel is provided at the back end portion on the top of the fixed top panel. The space between the movable top panel and the fixed top panel can then be screened by the aforesaid panels. Furthermore, a metal lock fitting is fixed to a front end of the movable top panel and an electromagnetic lock device that corresponds with the metal lock fitting is provided on the fixed top panel. Wiring for the electromagnetic lock device is made in such a manner that external centralized control of the locking and unlocking of a plurality of desks is possible. However, both the locking and unlocking operations may not be performed by the electromagnetic lock device. For example, the electromagnetic lock device may only perform the unlocking operation. 
     
    
     BRIEF DESCRIPTION OF THE DRAWING FIGURES  
       [0018]     The invention will now be described, by way of example, with reference to the accompanying drawings, in which:  
         [0019]      FIG. 1  is a perspective view showing a classroom desk according to an embodiment of the present invention;  
         [0020]      FIG. 2  is a side view showing an upper portion of the classroom desk according to the embodiment of the present invention;  
         [0021]      FIG. 3  is a partial top plan view of the classroom desk according to the embodiment of the present invention;  
         [0022]      FIG. 4  is a schematic diagram showing a mechanism for simultaneously unlocking a plurality of classroom desks;  
         [0023]      FIG. 5  is a side view showing a first example of a conventional classroom desk; and  
         [0024]      FIG. 6  is a side view showing a second example of a conventional classroom desk. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0025]     Referring to  FIGS. 1, 2  and  3 , a classroom desk  100  of a present embodiment is provided with a movable top panel  1  and a fixed top panel  2 . The movable top panel  1  is capable of being opened and closed. The movable top panel  1  covers the fixed top panel  2  on which a small-sized computer  30  is mounted. The fixed top panel  2  is supported by a support member  3 a which is fixed to an upper end of a leg  3  and extends toward the front of the desk  100  (to the right in  FIG. 3 ). A support box  10  is provided on each of the right and left sides along the back portion of the fixed top panel  2 . A top surface of each support box  10  is made flat. A bottom end of the leg  3  is secured to the floor of a classroom. A connection panel and a modesty panel are provided to connect the right and left legs  3 .  
         [0026]     The movable top panel  1  is connected to each support box  10  by a first link member  4  and a second link member  5 . The movable top panel  1 , in a closed state, is parallel to the fixed top panel  2 , which is spaced apart from the movable top panel  1  by approximately 7 to 10 cm in this embodiment. The movable top panel  1 , in an opened state, stands vertically at the back of the fixed top panel  2  in such a manner that about half of the depth of the movable top panel  1  is located below the height of the fixed top panel  2 . In this case, the movable top panel  1  extends below a point approximately 25 cm above the upper surface of the fixed top panel  2 .  
         [0027]     The top surface of movable top panel  1  is generally as large as the top surface of fixed top panel  2 . In order to screen a space generated between the movable top panel  1  and the fixed top panel  2  when the movable top panel  1  is in a closed state, a side panel  1   a  at each of the right and left end portions, and a front panel  1   b  at a front end portion, are respectively provided on the underside of the movable top panel  1 . Across the back, a back panel  2   a  is provided and extends between the right and left support boxes  10 . The height of the side panel  1   a  and the front panel  1   b  is the same as that of the support box  10 . When the movable top panel  1  is in a closed state, the back portion thereof is arranged on the support box  10 .  
         [0028]     One end of the first link member  4  and the second link member  5  is connected to the side panel  1   a  on the movable top panel  1  (see  FIG. 2 ). The other end of each link member is connected to the support box  10 . In other words, one end of the first link member  4  is linked with a rearward portion of the side panel  1   a  via a pin  6 , and one end of the second link member  5  is linked with a forward portion of the side panel  1   a  via a pin  7 . The other end of the first link member  4  is rotatably connected to a shaft  11  which is supported by a bearing  12  attached to the support box  10 . The other end of the second link member  5  is linked to fixing metal  10   a  via a pin  8 . The fixing metal  10   a  is secured to the support box  10  and extends toward the front. In  FIG. 2 , a stopper  9  for supporting the movable top panel  1  in a vertically open state is attached to the support box  10  so that the first link member  4  can abut thereon.  
         [0029]     A rotary damper  14  which restricts the forward and backward rotations of the first link member  4  is provided to the shaft  11 . Reference number  13  (see  FIG. 3 ) indicates a support metal fitting that supports the rotary damper  14 .  
         [0030]     A metal lock fitting  16  is secured to a front end of the side panel  1   a.  At a front end of the fixed top panel  2 , an electromagnetic lock device  17  is provided to catch the metal lock fitting  16 .  
         [0031]     The electromagnetic lock device  17  automatically locks the desk via a spring mechanism when the movable top panel  1  is shut. In order to unlock the desk, a solenoid is energized to compress the spring mechanism, releasing the lock device  17 . As shown in  FIG. 4 , a lecturer&#39;s desk  50  is electrically connected to each classroom desk  100  via wiring  110 . An unlock switch  51  may be provided on the lecturer&#39;s desk  50  so that the movable top panel  1  of all of the classroom desks  100  can be simultaneously unlocked and opened.  
         [0032]     The operation of the classroom desk constituted as above is now explained.  
         [0033]     The small-sized computer  30  is mounted to the top surface of the fixed top panel  2 . In classes not requiring the use of the computer  30 , the computer  30  is hidden by the movable top panel  1  as indicated by the solid lines in  FIG. 2 . Participants can then take classes using their textbooks and notebooks on the top surface of the movable top panel  1 .  
         [0034]     During this time, when the movable top panel  1  is closed, the lower ends of the side panel  1   a  and the front panel  1   b  of the movable top panel  1  abuts on the top surface of the fixed top panel  2 . The back portion of the movable top panel  1  is arranged on the tops of the support blocks  10 . A space between the movable top panel  1  and the fixed top panel  2  is screened by the right and left side panels  1   a,  the front panel  1   b,  and the back panel  2   a.  The metal lock fitting  16  of the movable top panel  1  is engaged by the electromagnetic lock device  17  on the fixed top panel  2 . The desk is in a locked state.  
         [0035]     In classes requiring the use of the computer  30 , the lecturer directs the participants to open the movable top panel  1 , activating the unlock switch  51 . Each participant holds and raises the front end portion of the movable top panel  1 . As a result, as shown by the dotted lines in  FIG. 2 , the movable top panel  1  stands vertically at the back of the desk in such a manner that about half a depth of the movable top panel  1  is located below the height of the fixed top panel  2 . At this time, the first link member  4  is abutted on the stopper  9 . Even if a user attempts to abruptly open the movable top panel  1 , the rotary damper  14  dampens the rotation speed of the shaft  11  to which the first link member  4  is connected.  
         [0036]     The pin  6 , attached to one end of the first link member  4 , is positioned lower than the shaft  11 . The stopper  9  is positioned closer to the shaft  11  and lower than the shaft  11 . Thus, the weight of the movable top panel  1  is centered on the back of the desk. Consequently, when the movable top panel  1  is positioned in an opened state, it does not get inadvertently closed by vibration or shock.  
         [0037]     The participants can keep the computer  30  display upright while taking the class. An upper end of the upright display is at about the same height as an upper end of the movable top panel  1 . Thus, the participants&#39; front view is not significantly blocked. There is no associated problem in communicating with the lecturer.  
         [0038]     After the class, the participants hold the upper end portion of the movable top panel  1  located in a vertical position and rotate it down to the front. Since the rotary damper  14  is provided, the rotation speed of the shaft  11  is dampened. Therefore, even if the participants fail to support the movable top panel  1 , the movable top panel  1  does not bang shut. When the movable top panel  1  abuts on the fixed top panel  2 , the metal lock fitting  16  attached to the movable top panel  1  is automatically engaged by the electromagnetic lock device  17 . The desk is in a locked state.  
         [0039]     The present invention is not limited to the above embodiment, and other modifications and variations are possible without departing from the sprit and scope of the present invention.  
         [0040]     In the above embodiment, for instance, a classroom desk is explained for use by only one person. However, a classroom desk which is extended in a lateral direction so that two or three persons can sit together is most commonly used. In this case, the fixed top panel may be produced long enough for two or three persons. However, a movable top panel may be provided for each person, but forming a continuous top surface with only a slight slit between the adjacent panels. In this manner, there is no appreciable border between the adjacent panels. Consequently, a participant is allowed to occupy a larger area of a desktop when a neighboring participant is not present.