Abstract:
A plane jigsaw puzzle has multiple plastic pieces with concavo-convex structures on side edges, where the plastic puzzle pieces are matched and connected to concavo-convex structures. A chamfer angle is set at the edge between pieces, and the height of the chamfer angle to the edge interface of the two adjacent pieces is from 5% to 50%. The contact area of the two opposite adjacent pieces is 95% to 50% of the contact area of the corresponding edges.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a jigsaw, and more particularly to a plane jigsaw puzzle that is made of plastic and may be firmly pieced by itself. 
         [0003]    2. Description of Related Art 
         [0004]    Jigsaw puzzles are playthings that consist of pieces that each piece has recessed or protruding engaging members formed thereon to engage adjacent pieces together. A conventional jigsaw puzzle has pieces made of paper. Because of the paper material characteristics and manufacturing processes, a contacting area between adjacent pieces is insufficient to provide firm and stable connection therebetween. Therefore, the conventional jigsaw puzzle employs a flat frame having a bottom supporting board to hold the completely pieced jigsaw puzzle. However, the additional frame increases a cost of the jigsaw and disadvantages storing or carrying the jigsaw puzzle. Furthermore, the configurations and color tones of the frames and jigsaw puzzle assembled from the pieces are distinct and hard to match each other for harmonious visual effect. Another conventional jigsaw puzzle made of plastic is sufficient rigid and firm to connect adjacent pieces together. However, sides of adjacent plastic pieces fully contact each other to provide a flat and smooth drawing instead of a pieced drawing with obvious piece boundaries as shown by a conventional paper jigsaw puzzle. Therefore, a visual effect of the plastic jigsaw puzzle is not classical. Because plastic is harder and less deformable when compared to paper, higher manufacturing precision of the jigsaw puzzle is needed for successfully piecing the jigsaw puzzle. Furthermore, piecing the plastic jigsaw puzzle easily clips and injures a user&#39;s fingers inadvertently so using the plastic jigsaw puzzle is not safe. 
       SUMMARY OF THE INVENTION 
       [0005]    The main objective of the present invention is to overcome the defects of the prior art and provide a plane jigsaw puzzle that has advantages of self-connection, lower manufacturing precision requirement, beautiful appearances and is made of safe plastic. 
         [0006]    The present invention is achieved according the following technologies. 
         [0007]    A plane jigsaw puzzle in accordance with the present invention comprises a jigsaw formed by assembling multiple plastic-made pieces together and adjacent plastic-made pieces connected together through protruding and notched engaging members formed therebetween and engaging each other. The plane jigsaw puzzle is characterized in that each plastic-made piece has a front surface and a chamfer edge formed adjacent the top surface and having a height being 5% to 50% of a height of a contacting area between adjacent plastic-made pieces. The contacting area of the two opposite adjacent pieces is 95% to 50% of the contacting area of the corresponding edges. To achieve great fastening effects, the contacting area of the two opposite adjacent pieces is 60% to 80% of the contacting area of the corresponding edges. A best contacting area rate is 75%. The plane jigsaw puzzle increases a contacting area between adjacent pieces, improves the connection of the pieces and is assembled without additional fastening devices. The plane jigsaw puzzle has the chamfer edge being a rounded chamfer edge to provide classical visual effect. The assembled plane jigsaw puzzle has similar feel of a conventional jigsaw puzzle. Furthermore, an user may identify obverse and reverse sides of the pieces by the rounded chamfer edges, especially when the pieces are translucent. The rounded chamfer edges also decrease deckle edges of the plastic-made pieces during manufacturing processes and therefore increase the safety of using the plane jigsaw puzzle. When the plane jigsaw puzzle is assembled, rounded chamfer edges allow more deformation and larger operational space between adjacent pieces and lowers the manufacturing precision requirement of the pieces. 
         [0008]    The plane jigsaw puzzle further comprises an outer frame mounted around the jigsaw and assembled from multiple frame segments, wherein adjacent frame segments are connected through protruding and notched engaging members formed therebetween and engaging each other to form the outer frame. 
         [0009]    In the plane jigsaw puzzle, each frame segment of the outer frame has an inside edge and at least one protruding or notched engaging member formed on the inside edge respectively engaging at least one protruding or notched engaging member that is formed on an adjacent piece of the jigsaw for improving the structures and harmonize the configurations of the plane jigsaw puzzle. In the plane jigsaw puzzle, each frame segment has two sides and two sets of at least one protruding or notched engaging member formed respectively on the sides and respectively engaging the sets of adjacent frame segments. 
         [0010]    In the plane jigsaw puzzle, each frame segment of the outer frame has a decoration bar covering the at least one protruding or notched engaging members on the inside edge of the frame segment and covering the at least one protruding or notched engaging member of an adjacent piece that respectively engages that of the frame segment for beautiful purposes. 
         [0011]    In the plane jigsaw puzzle, the outer frame further has a fastener connecting the frame segments together to prevent inadvertent deformation and facilitate suspending the plan jigsaw puzzle. In the plane jigsaw puzzle, the fastener has multiple mounting slots and reinforcing bars, the mounting slots are defined respectively in bottoms of the frame segments and each reinforcing bars are mounted in and through more than one of the mounting slots to connect the frame segments together. The reinforcing bars may be made of plastic or metal. 
         [0012]    In the plane jigsaw puzzle, the outer frame has an anti-skid texture formed on a top surface and an outer surface of the outer frame to facilitate handholding or moving the plane jigsaw puzzle. 
         [0013]    The present invention increases contacting areas between adjacent pieces so that the pieces may be connected together by themselves and will not inadvertently disassemble when moving. Furthermore, the outer frame with the fastener is mounted around the jigsaw of the pieces for aesthetic purposes and facilitates moving. The outer frame assembled from the frame segments facilitates carrying the plane jigsaw puzzle, matches the jigsaw and having decoration bars to make the plane jigsaw puzzle beautiful. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  is perspective view of a conventional jigsaw puzzle in accordance with the prior art; 
           [0015]      FIG. 2  is an operational side view of a cutter cutting a paperboard for manufacturing the conventional jigsaw puzzle; 
           [0016]      FIG. 3  is a perspective view of a conventional frame for holding the conventional jigsaw puzzle; 
           [0017]      FIG. 4  is a perspective view of a first embodiment of a jigsaw of a plane jigsaw puzzle in accordance with the present invention; and 
           [0018]      FIG. 5  is a cross sectional side view of the jigsaw of the plane jigsaw puzzle of the first embodiment; 
           [0019]      FIG. 6  is an exploded top perspective view of an outer frame of the plane jigsaw puzzle of the first embodiment; 
           [0020]      FIG. 7  is an exploded bottom perspective view of the outer frame of the plane jigsaw puzzle in  FIG. 6 ; 
           [0021]      FIG. 8  is a partially exploded top perspective view of the jigsaw and outer frame of the plane jigsaw puzzle of the first embodiment; 
           [0022]      FIG. 9  is a bottom perspective view of the plane jigsaw puzzle of the first embodiment showing that the jigsaw and outer frame are assembled completely; 
           [0023]      FIG. 10  is a partially exploded bottom perspective view of the plane jigsaw puzzle of the first embodiment; 
           [0024]      FIG. 11  is a top perspective view of the complete plane jigsaw puzzle of the first embodiment; 
           [0025]      FIG. 12  is an exploded top perspective view of an outer frame of a second embodiment of the plane jigsaw puzzle in accordance with the present invention; 
           [0026]      FIG. 13  an exploded bottom perspective view of the outer frame of the plane jigsaw puzzle in  FIG. 12 ; 
           [0027]      FIG. 14  is a partially exploded top perspective view of the jigsaw and outer frame of the plane jigsaw puzzle of the second embodiment; 
           [0028]      FIG. 15  is a bottom perspective view of the complete plane jigsaw puzzle of the second embodiment; 
           [0029]      FIG. 16  is a partially exploded bottom perspective view of the plane jigsaw puzzle of the second embodiment; and 
           [0030]      FIG. 17  is a top perspective view of the complete plane jigsaw puzzle of the second embodiment. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0031]    The following descriptions are accompanied with the aforementioned attached drawings to explain the present invention. 
         [0032]    With reference to  FIG. 1 , a conventional jigsaw puzzle  1 ′ is assembled from pieces that each piece has an outer edge and notched or protruding Ω-shaped engaging members. The jigsaw puzzle has a drawing formed on one surface thereof. With further reference to  FIG. 2 , the jigsaw puzzle  1 ′ is made of paper. During manufacturing processes, a cutter  7  is used to stamp and cut a paperboard to form a jigsaw puzzle as shown in  FIG. 1 . The paper jigsaw puzzle  1 ′ has a small contacting area between adjacent pieces. A main connection between adjacent pieces is engaging the notched and protruding Ω-shaped engaging members to prevent the jigsaw puzzle from transversely disassembling inadvertently. Because no supporting force is applied to and holds the jigsaw puzzle F along a depth direction thereof, the jigsaw puzzle  1 ′ cannot be moved without further assistance. With further reference to  FIG. 3 , to move or suspend the jigsaw puzzle  1 ′, an outer frame  3 ′ is used to hold the whole jigsaw puzzle  1 ′. However, using the outer frame  3 ′ is inconvenient and the configurations and color tones of the outer frame  3 ′ and the jigsaw puzzle  1 ′ are not matching. 
         [0033]    Therefore, the present invention provides a plane jigsaw puzzle and the following examples are presented to explain such plane jigsaw puzzle. 
       First Embodiment 
       [0034]    With reference to  FIG. 4 , a first embodiment of the plane jigsaw puzzle  1  comprises a jigsaw having multiple pieces. The pieces are detachably connected and assembled together to form the jigsaw puzzle and each piece has an outer edge and multiple Ω-shaped notched or protruding engaging members. Adjacent pieces are connected through the notched or protruding Ω-shaped engaging members to prevent inadvertent transverse disassembly. With reference to  FIG. 5 , each piece has a top surface and multiple side surfaces. A contacting area  2  between adjacent pieces of the plane jigsaw puzzle  1  is 75% of an area of one side surface of each piece. A height h of the contacting area  2  is ¾ of a height H of each piece. A chamfer edge may be a rounded chamfer edge, is formed adjacent the top surface, may be formed between the top surface and sides surfaces of each piece. A height of the chamfer edge is 5% to 50% of the height h of the contacting area of adjacent pieces. Because the contacting area greatly increases when compared to that of a conventional jigsaw puzzle, connection between adjacent pieces is improved. The assembled plane jigsaw puzzle  1 ′ is structurally firm without additional holding devices. The pieces are made of durable plastic to ensure repeating uses without decreasing the contacting area  2  of adjacent pieces so that the plane jigsaw puzzle  1 ′ is structurally stable. The chamfer edge of the pieces makes the complete plane jigsaw puzzle  1 ′ show classical visual effect, facilitates recognizing obverse and reverse sides of the piece and prevents deckle edges. 
         [0035]    With further reference to  FIG. 6 , the plane jigsaw puzzle  1  further comprises an outer frame  3  that is rectangular, assembled from multiple frame segments and mounted around the jigsaw. Each frame segment has connecting members. The frame segments are classified into corner frame segments  31  and linear frame segments  32 ,  33 . Each corner frame segment  31  has a top, a bottom, two side edges, a protruding Ω-shaped engaging member  311  and a Ω-shaped notched engaging member  312 . The protruding and notched Ω-shaped engaging members  311 ,  312  are formed respectively on the side edges. Each linear frame segment  32 ,  33  is connected detachably to an adjacent corner frame segment  31  or linear frame segment  32 ,  33  and has a top, a bottom, two opposite side edges, an inside edge and three Ω-shaped engaging members  321 ,  322 ,  323 . The Ω-shaped engaging members  321 ,  322 ,  323  are formed respectively on the side edges and inside edge of the linear frame segment  32 ,  33  and may be protruding or notched. The protruding or notched Ω-shaped engaging member  321 ,  322  on each side edge of the linear frame segment  32 ,  33  engages that of an adjacent corner or linear frame segment  31 ,  32 ,  33 . The protruding or notched Ω-shaped engaging member  323  on the inside edge engages that of an adjacent piece. The corner frame segments  31  and linear frame segments  32 ,  33  are connected to form the rectangular outer frame  3 . The protruding or notched Ω-shaped engaging member on the inside edge of the linear frame segment  32 ,  33  engages one protruding or notched Ω-shaped engaging member of an adjacent piece of the jigsaw. With further reference to  FIG. 8 , the assembled jigsaw may combine the assembled outer frame  3  through the protruding or notched Ω-shaped engaging members  323  on the inside edges of the linear frame segments  32 ,  33  and those of the pieces to form the plane jigsaw puzzle  1 . 
         [0036]    With further reference to  FIGS. 7 ,  9  and  10 , the outer frame  3  further has a fastener connecting the corner and linear frame segments  31 ,  32 ,  33  together. The fastener may be multiple mounting slots  4  and multiple reinforcing bars  5 . Each of the corner and linear frame segments  31 ,  32 ,  33  further has a mounting slot  4  defined in the bottom thereof. The mounting slots  4  of the corner and linear frame segments  31 ,  32 ,  33  communicate with one another. The reinforcing bars  5  are made of plastic or metal and are mounted in and through more than one of the communicating mounting slots  4  to connect the corner and linear frame segments  31 ,  32 ,  33  together and structurally strengthen the outer frame  3 . With further reference to  FIG. 11 , the jigsaw, outer frame  3  and reinforcing bars  5  are assembled together to form the plane jigsaw puzzle  1  without additional holding devices such as bottom supporting boards. The assembled plane jigsaw puzzle  1  is structurally firm and facilitates movement and suspension thereof. Furthermore, the outer frame  3  may further have an anti-skid texture  34  formed on a top surface and an outer surface of the outer frame to facilitate handholding or moving the plane jigsaw puzzle  3 . 
       Second Embodiment 
       [0037]    With reference to  FIGS. 12 to 17 , a second embodiment of the plane jigsaw puzzle is similar to the first embodiment and further has multiple decoration bars  6  to cover the protruding or notched Ω-shaped engaging members of the outer frame  3  and those of the pieces that engage each other. Each linear frame segment  32 ,  33  has a decoration bar  6 . The decoration bar  6  is formed on the linear frame segment  31 , covers the protruding or notched Ω-shaped engaging member  323  on the inside edge and covers the protruding or notched Ω-shaped engaging member of an adjacent piece engaging the Ω-shaped engaging member  323  on the inside edge. Each corner frame segment  31  has an inside edge, multiple protruding and/or notched Ω-shaped engaging members  313 ,  314  and a decoration bar  6 . The protruding and/or notched Ω-shaped engaging members  313 ,  314  are formed on the inside edge and respectively engage those of adjacent pieces. The decoration bar  6  is formed on the corner frame segment  31 , covers the protruding and/or notched Ω-shaped engaging members  313 ,  314  of the inside edge and covers the protruding or notched Ω-shaped engaging members of an adjacent piece respectively engaging the Ω-shaped engaging members  313 ,  314  of the inside edge, as shown in  FIGS. 15 and 16 . After the plane jigsaw puzzle  1  is assembled completely as shown in  FIG. 17 , the engaged Ω-shaped engaging members of the outer frame  3  and pieces are hidden under the decoration  6  for aesthetic purposes. 
         [0038]    The present invention is not limited by the aforementioned two embodiments, any configurations increasing the contacting area between adjacent pieces to fasten the plane jigsaw puzzle are included in the scope of the present invention to be protected.