Abstract:
A collapsible clipboard includes a bottom case, a cap board and an upper board formed respectively integral of plastic, and all of them are pivotally connected with each other, enabling the upper board and the cap board respectively liftable from the bottom case easily and quickly.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to a collapsible clipboard, particularly to one simple to assemble and collapse. 
     Conventional clipboards are popular, and used by workers engaging in warehouse, goods delivery, etc., and often provided with a hollow space for keeping necessary data therein. A known conventional clipboard  10  shown in FIGS. 1 and 2 includes a bottom case  11  made of a thin metal plate pressed to have four side vertical walls, a board  12  closed on the bottom base  11 , and a drawer  13 . The bottom case  11  have an inner hollow space  111  for containing paper or data, plural pivot supporters  112  formed spaced apart on an upper edge of a front vertical wall and respectively having a pivot hole  113 . The board  12  has plural pivot supporters  121  with a pivot  122  holes spaced apart to interpose alternately with the pivot supporters  112  of the bottom case  11  for an elongate pivot  15  to fit in all the pivot supporters  112  and  121  so as to combine pivotally the board  12  with the bottom case  11 . Further, the board  12  has an elastic clip  16  fixed on a middle section of a front end for pinching paper on the surface  123  of the board  12 . In addition, a drawer case  124  is riveted under the right front bottom of the board  12  for a drawer  13  to slide in and out of. Then a calculator  17  can be stored in the drawer  13  to be taken out and used when necessary. The bottom case  11  has an aperture  114  formed in a front portion of the right side wall to face the drawer case  124  and a horizontal engage slot  115  formed in the middle section of a rear wall. The board  12  has an engage elastic bent small plate  125  movably fixed with rivets on the middle section of a rear end to fit through the horizontal engage slot  115  when the board  12  is closed on the bottom base  11  to secure the board  12  on the bottom base  11 . 
     The conventional clipboard  10  still has the following disadvantages, in spite of its usefulness. 
     (1) The board  12  and the bottom case  11  are pivotally connected with the elongate pivot  15  fitting in the pivot holes  113  and  122  of the pivot supporters  112  and  121 , all of which are to be aligned before the elongate pivot  15  can fit in. Then it may take much time to finish connecting pivotally the board  12  and the bottom case  11 , very troublesome. In addition, the board  12  and the bottom case  11  are made of thin metal plates bent and then riveted, resulting in a high cost. 
     (2) The drawer case  124  for the drawer is located under the board  12  and placed in the interior  111  of the bottom case  11 , so the right side wall of the bottom case  11  has to be cut the aperture  114  for the drawer  13  to move in and out. So the dimension of the interior  111  is reduced so that the height of the bottom case has to be increased for containing papers for use. 
     SUMMARY OF THE INVENTION 
     The objective of the invention is to offer a collapsible clipboard made of plastic, having a bottom case and a cap board pivotally connected to the bottom case, and an upper board smaller than the cap board pivotally connected to the bottom case. Then the upper board has plural hooks fixed on a lower surface to hold a calculator to be taken off if it is to be used. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     This invention will be better understood by referring to the accompanying drawings, wherein: 
     FIG. 1 is an exploded perspective view of a known conventional clipboard: 
     FIG. 2 is a perspective view of the known conventional clipboard: 
     FIG. 3 is an exploded perspective view of a collapsible clipboard in the present invention: 
     FIG. 4 is a perspective view of the collapsible clipboard in the present invention: 
     FIG. 5 is a front view of an upper plate with some stationery hooked on its lower surface in the present invention: 
     FIG. 6 is a partial side cross-sectional view of the collapsible clipboard in the present invention, showing how the upper board lifted up to the front side: 
     FIG. 7 is a perspective view of the collapsible clipboard in the present invention, showing paper placed on a cap board and the upper board being lifted up: 
     FIG. 8 is a perspective view of a collapsible clipboard without the upper board not combined in the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A preferred embodiment of a collapsible clipboard  20  in the present invention, as shown in FIGS. 3 and 4, includes a bottom case  21 , a cap board  22 , and an upper board  23  as main components 
     The bottom case  21  is made of plastic, having a rectangular shape, an inner hollow interior  211 , a plurality of tapered ribs  212  formed on an inner side of the two lengthwise sidewalls, a hook hole  213  formed in a middle section of a front portion of the bottom, a separate wall  214  parallel to and near the rear wall to define a small elongate room  215  for storing stationary. A plurality of pivot ears  216  respectively with a pivot groove  217  are provided spaced apart on an outer side of the front sidewall of the bottom case  21 , and each pivot groove  217  has an upper opening  2171  of a little smaller width than the inner diameter of the pivot groove  217 . Further, plural stop blocks  218  are fixed under the pivot ears  216  on the outer side of the front sidewall of the bottom case  21 , and a small engage projection  219  is formed to protrude out on a middle section of the rear sidewall of the bottom case  21 . 
     The cap board  22  is made of plastic, having the same shape and size as the bottom case  21  to close on the bottom case, having a pivot  221  formed on a middle section of a front side and a shaft  222  of a small diameter respectively formed to extend from two ends of the pivot  221 . The shafts  221  fit in the pivot grooves  217  of the two inner pivot ears  216 , enabling the cap board  22  to be lifted up with the shafts  222  as pivots from the bottom case  21 . Further, an elastic clip  224  is fixed near the pivot  221  on the middle section of the front-end portion of the surface  223  of the cap board  22 .for pinching paper, and an engage projection  225  is formed on a middle section of the rear end to engage the projection  219  of the bottom case  21 . 
     The upper board  23  is also made of plastic, having a rectangular shape, smaller than the cap board  22 , covering on the cap board  22 , having a recess opening  231  in a front end portion to let the clip  224  expose when the upper board is closed on the cap board  22 . The upper board  23  further has two projecting portions  232  at two sides of the recess opening  231 , and each projecting portions  232  has a shaft  233  extending from a lower front end to both sides to fit in the outer two pivot grooves  217  of the two pivot ears  216 , enabling the upper board  23  lifted up from the board  22  with the shafts  233  as pivots. Next, referring to FIG. 5, the upper board  23  further has plural pre-arranged hooks  234  on a lower surface to hold a calculator  300 , pens  3 , and sidewalls  235  on two sides of the bottom to raise the upper board a little on the board  22  when it is closed on the board  22 . 
     In assembling, referring to FIGS. 3,  4  and  6 , firstly, the two small shafts  222  of the board  22  are placed on the openings  2171  of the two inner pivot ears  216  and then press the board  22  down, then the two shafts  222  slide into the pivot grooves  217  to secure the cap board  22  with the bottom case  21 . Then the upper board  23  is also secured with the bottom case  21  in the same way, with the two shafts  233  fitting in the two outer pivot grooves  217  through the openings  2171 . 
     In using, referring to FIGS. 6 and 7, the hollow interior  211  of the bottom case  21  stores papers  50 , paper to be written is to be placed on the surface  223  of the board  22  and be pinched with the clip  24  after the upper board is first lifted up until the two side projections  232  touch the stop blocks  218  and stabilized, as shown in the dotted lines in FIG.  6 . Then the upper board  23  and the cap board  22  are separated with a large angle, easy for a user to take a calculator  30  or a pen  40  from the lower surface of the upper board  23 . When a paper  50  placed on the cap board  22  is written fully and to be stored in the bottom case  21 , the paper  50  is taken off, with the cap board  22  lifted up, and with the engage projection  225  disengaging from the small engage projection  219  to let the hollow interior of the  211  of the bottom case  21  expose. Then the paper  50  may be placed in the hollow interior  211 , guided by the tapered ribs  212 , and the cap board  22  is closed on the bottom case  21  again. When the cap board  20  is finished in use, the upper board  23  is pulled down on the cap board  22 , and the clipboard  20  can be hung up with the hang hole  213  of the bottom case  21 . If there is still paper  50  pinched on the board  222 , the two side walls  235  may rest on the paper  50  to close smoothly the upper board  23  on the cap board  22 . 
     Besides, the stop blocks  218  may be formed on the front end of the two projections  232 , so when the upper board  23  is lifted up from the cap board  22 , the stop blocks  218  is also lifted up to be stopped at the front end of the bottom case  21 , having the same function. 
     As shown in FIG. 8, the upper board  23  may be not needed, if a calculator is not needed. 
     The invention has the following advantages, as understood from the aforesaid description. 
     1. The clipboard is made of plastic, except the elastic clip  224  fixed on the cap board  22 , with the other components combined together without need of a second process. In addition, the bottom case  21 , the cap board  22  and the upper board  23  can be combined together easily and quickly by means of the pivot grooves  271  in open condition, lessening work time and labor. 
     2. The inner hollow interior of the bottom case  21  has a height shorter than the conventional clipboard so as to be able to contain the same volume of papers as the conventional one, and the cap board  22  has a shorter height also than the conventional one, convenient to carry along. In packaging the bottom case  21 , the cap board  22  and the upper board  23  may be collapsed to permit the upper board  23  possible to be placed in the inner hollow interior  211  of the bottom case  21  to save the whole size of a carton, reducing cost for transportation. 
     While the preferred embodiment of the invention has been described above, it will be recognized and understood that various modifications may be made therein and the appended claims are intended to cover all such modifications that may fall within the spirit and scope of the invention.