Abstract:
A fastener-free box with fast assembly is disclosed, comprising a baseboard, a front board, a rear board, a left board, a right board, and a cover board. An insert-connection structure that is configured to form an insert connection with a respective adjacent board is integrally formed on each of the board; any three perpendicular boards are configured to form an interlocking structure among them; and, a connection structure configured to couple with each other is integrally and individually formed on each of the cover board and the rear board. The structure of the box is simple. In addition, an interlocking structure can be formed after the box is assembled, enabling an even more robust box structure. Furthermore, the box is ideal for outdoor use as it is water proof.

Description:
RELATED APPLICATIONS 
       [0001]    This application claims priority to Chinese. patent application 201610338549.0, filed May 20, 2016, and entitled “FASTENER-FREE BOX WITH FAST ASSEMBLY”, the disclosure of which is hereby incorporated herein by reference in its entirety for all purposes. 
       FIELD OF THE INVENTION 
       [0002]    The present disclosure relates to a box or a storage structure. More particularly, it relates to a fastener-free box with fast assembly. 
       BACKGROUND 
       [0003]    Nowadays, many families place a storage box, e.g. deck box, in the outdoor courtyard for storage of gardening tools or other items so that the courtyard is tidy and appealing. Due to the relative large dimensions, such boxes are usually purchased in an unassembled manner, which need to be assembled at the customer&#39;s home. For now, to install a storage box, the customer often uses screw drivers and fasteners such as screws to securely connect the multiple boards. Not only is this process very time-consuming and laborious, it is also low in assembly efficiency. Consequently, the screws need to be loosened one by one to disassemble the box, which is highly inconvenient. Moreover, for boxes fastened by screwed connections, mounting holes must be reserved in advance on the baseboard, side boards, and cover board during their manufacture. For precise assembling, errors in the positions of such reserved mounting holes are not allowed. Otherwise, it may not be assembled in place, or it may be impossible to assemble at all. Also, for some boxes, there are pre-embedded fasteners in the reserved mounting holes. Therefore, additional follow-up manufacturing processes are required after forming the boards to install the pre-embedded fasteners. Such installations are usually completed by workers manually with low-efficiency. In conclusion, the prior box structure needs improvements for the benefits of consumer&#39;s experience as well as industrial manufactures. 
       SUMMARY OF THE INVENTION 
       [0004]    One technical solution of the present disclosure is to provide a fastener-free and robust box that is capable of fast assembly and is convenient to assemble. 
         [0005]    A technical solution to solve the above problem is a fastener-free box with fast assembly, comprising: a baseboard ( 1 ), a front board ( 2 ), a rear board ( 3 ), a left board ( 4 ), a right board ( 5 ), and a cover board ( 6 ), wherein an insert-connection structure configured to form an insert connection with a respective adjacent board is integrally formed on each of the baseboard ( 1 ), the front board ( 2 ), the rear board ( 3 ), the left board ( 4 ), and the right board ( 5 ); wherein any three perpendicular boards of the baseboard ( 1 ), the front board ( 2 ), the rear board ( 3 ), the left board ( 4 ), and the right board ( 5 ) are configured to form an interlocking structure among them; and wherein a connection structure configured to couple with each other is integrally and individually formed on each of the cover board ( 6 ) and the rear board ( 3 ). 
         [0006]    According to some embodiments, a first insert-connection structure may be formed between the left board and the baseboard, limiting the left board to only slide frontward and backward relative to the baseboard; a first insert-connection structure may be formed between the right board and the baseboard, limiting the right board to only slide frontward and backward relative to the baseboard; a second insert-connection structure may be formed between the front board and the left board and between the rear board and the left board, preventing the left board from moving frontward and backward; a second insert-connection structure may be formed between the front board and the right board and between the rear board and the right board, preventing the right board from moving frontward and backward; a third insert-connection structure may be formed between the rear board and the baseboard, preventing the rear board from moving relative to the baseboard; and, a third insert-connection structure may be formed between the front board and the baseboard, preventing the front board from moving relative to the baseboard. In this way, with the first, second, and third insert-connection structures, any three perpendicular boards of the baseboard, the front board, the rear board, the left board, and the right board can form an interlocking structure among them, avoiding relative displacement when the assembly is completed. 
         [0007]    Many suitable structures may be applied as the first and second insert-connection structures. According to some embodiments, a horizontal retaining groove of a front-rear direction with an inward opening may be provided at the bottom of each of the left board and the right board, the horizontal retaining groove being a dovetail groove or a T-shape groove; a horizontal rib of a front-rear direction capable of forming an insert connection with the horizontal retaining groove may be provided at each of the left and right sides of the baseboard; the corresponding horizontal retaining groove and horizontal rib form the first insert-connection structure; a vertical retaining groove of an up-down direction with an inward opening may be provided on the front side and the rear side of each of the left board and the right board, the vertical retaining groove being a dovetail groove or a T-shape groove; a vertical rib of a up-down direction capable of forming an insert connection with the vertical retaining groove may be provided on the left side and the right side of each of the front board and the rear board; and, the corresponding vertical retaining groove and vertical rib form the second insert-connection structure. Naturally, the horizontal and vertical retaining grooves may be implemented in any other form of retaining grooves. 
         [0008]    According to some embodiments, the horizontal retaining groove may be closed at the front end or the rear end; the vertical retaining groove may be closed at the lower end; a lower step may be formed at both front and rear sides at the top portion of each of the left board and the right board; an upper end of the vertical retaining groove opens at the corresponding lower step; a lug protruding from the vertical rib may be formed at both front and rear sides at the top portion of each of the front board and the rear board, the lug being pushed against the lower step when the corresponding vertical rib and vertical retaining groove are mated by insertion. As one end of the horizontal retaining groove is closed, it is possible for the left and right boards to properly mate with the baseboard by insertion. As the lower end of the vertical retaining groove is closed, it is possible for the front and rear boards to properly mate with the left and right boards by insertion, respectively. Furthermore, upward displacement of the left and right boards relative to the baseboard can be prevented when the lugs are pushed against the lower step. 
         [0009]    According to some embodiments, an insert slot may be formed at both front and rear sides of the baseboard; a pin may be integrally formed at the bottom of each of the front board and the rear board, the pin being mated with the corresponding insert slot by insertion to from the third insert-connection structure; the pin may extend downward from the bottom of each of the front board and the rear board and a buckling portion bending inward may be formed at the bottom of the pin; and, the buckling portion may be buckled reversely on an internal edge of the insert slot when the pin is inserted into the corresponding insert slot. In this way, when the front and rear boards are installed onto the baseboard, there may be no gap remaining at the insert slot viewing from inside the box. 
         [0010]    To further strengthen the insert-connection structure between the rear board and the baseboard, at least two insert slots may be formed at each of the front and rear sides of the baseboard, the insert slots being strip-shaped slots; at least two strip-shaped grooves may be provided at each of the front and rear sides of the baseboard, the strip-shaped grooves being provided in a left-right direction in an alternate manner with the insert slots of the corresponding side; a bar-shaped rib may be formed at the bottom of each of the front board and the rear board and provided in an alternate manner with the pin; and, the bar-shaped rib may be inserted into the corresponding strip-shaped groove when the pin is inserted into the corresponding insert slot. 
         [0011]    To prevent the rain from entering the box from outside, a water baffle edge may be formed at the top portion of each of the front board, the rear board, the left board, and the right board; and, a water baffle groove for receiving the water baffle edge may be formed surrounding a bottom surface of the cover board. 
         [0012]    To prevent deformation of the left board and the right board when being pushed inward, preferably, the internal wall of the water baffle groove formed at each of the left and right sides on the bottom surface of the cover board may constitute a solid reinforcing rib that abuts on the internal wall of the corresponding water baffle edge. 
         [0013]    To allow the cover board to form a better limiting structure with the left and right boards, preferably, at least two lugs may be formed at the top portion of each of the left board and the right board, and a groove for receiving the lug may be provided in a corresponding location at each of the left and right sides at the bottom of the cover board. 
         [0014]    Many types of rotatable structure are possible between the rear board and the cover board. According to some embodiments, the connection structure between the rear board and the cover board may be a rotatable hinge structure, comprising a hinge shaft and a hinge arm that is rotatably attached to the hinge shaft; the hinge shaft may be formed on one of the rear board and the cover board, and correspondingly the hinge arm may be formed on the other one of the rear board and the cover board; and a mating structure that only allows the hinge arm to fit into or detach from the hinge shaft in a certain direction may be formed between the hinge shaft and the hinge arm. 
         [0015]    According to some embodiments, the hinge shafts and the hinge mounts may be alternately provided at the top portion of the rear board; the hinge shaft may be a circular shaft with at least one lower cut face and at least one upper cut face formed along the axial direction of the hinge shaft, the lower cut face and the upper cut face being alternately and parallelly provided; correspondingly, the hinge arm may comprise an upper arc-shaped embracing arm and a lower arc-shaped embracing arm that are axially staggered in an up-down direction; and, the vertical distance between the opposite edges of the upper arc-shaped embracing arm and the lower arc-shaped embracing arm may be larger than the vertical distance between the lower cut faces and the upper cut face but smaller than the diameter of the hinge shaft. 
         [0016]    According to some embodiments, the cover board may be an arch-shaped structure that rises in the middle with both front and rear sides lowered. By use of an arch-shaped structure for the cover board, the structural and bearing strength of the cover board may be improved so that deformation is not easily caused by irradiation or rain, while the rain fallen onto the cover board can be readily guided away from the cover board. 
         [0017]    To reduce the package volume of the box, a first baffle bar in a left-right direction may be formed at each of the front and rear sides of the internal bottom surface of the baseboard and a second baffle bar in a front-rear direction may be formed at each of the left and right sides of the internal bottom surface of the baseboard; an upper end face of the second baffle bar may have an arc shape that is concaved inward from both ends to the middle; a middle portion of the second baffle bar and the internal bottom surface of the baseboard adjacent to this middle portion may together define an inward concave regain; and, an arc of the arc structure of the second baffle bar and an inward concavity of the concave region may match with the arch shape of the cover board. In this way, the inward concave structure on the baseboard can match with the arch shape of the cover board so that the package volume is advantageously reduced. 
         [0018]    According to some embodiments, a water baffle rib may be formed inside the region defined by the first baffle bar and the second baffle bar, and a water guide groove may be provided at a joint of the first baffle bar and the second baffle bar. By use of the water guide groove, it is possible to avoid water accumulation in the box. By use of the water baffle rib, it is possible to baffle water from items in the box even at the presence of some water inside the box. 
         [0019]    To further reduce the package volume, a fixing pin may be formed at the bottom of each of the left board and the right board, protruding therefrom horizontally; a limiting groove may be formed on the internal bottom surface of the cover board; and, when the left board and the right board are stacked with the top surface facing down onto the internal bottom surface of the cover board, the fixing pin is restrained in the limiting groove. 
         [0020]    According to some embodiments a reinforcing bar in a left-right direction may be fixed onto the front bottom of the cover board; a lock latch extending downward may be formed on the reinforcing bar; a recess portion that is sunken inward may be formed on an external surface of the front board, close to the upper edge thereof; a lock hole matching the lock latch may be provided on the recess portion; and, a guide ramp may be formed on the internal surface of the front board corresponding to the recess portion, the guide ramp being above the lock hole. The use of reinforcing bar can improve the structural strength of the cover board. When the cover board is closed, the lock latch may smoothly insert into the lock hole on the front board. 
         [0021]    To allow the respective boards to be restrained together during packing, when the cover board is stacked onto the baseboard, the left board and the right board stacked on the cover board, and the front board and the rear board stacked successively in a down-up direction onto the left board and the right board, the lock latch may face upward and constitute a stopper abutting on a side edge of the front board, and a limiting structure for receiving a rotatable structure portion of the rear board may be formed between another side edge of the front board and a corresponding side edge of the cover board. 
         [0022]    As a preferred embodiment of any of the above technical solution, the baseboard, the front board, the rear board, the left board, the right board, and the cover board may be blow molding boards; and, the front board, the rear board, the left board, the right board, and the cover board may have plaited structure formed on their external surfaces. 
         [0023]    Compared with the prior art, the present disclosure is advantageous in the following aspects: the overall structure of the box is simplified. An insert-connection structure capable of forming an insert connection with a respective adjacent board is integrally formed on each of the baseboard, and a connection structure capable of coupling with each other is integrally formed on each of the cover board and the rear board. Therefore, a user can perform fast assembly or disassembly without using any fasteners or tools. In addition, any three perpendicular boards of the baseboard, the front board, the rear board, the left board, and the right board are capable of forming an interlocking structure among them, enabling an even more robust box, or a box structure. Furthermore, as the box is water proof, it is ideal for outdoor use. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0024]      FIG. 1  is a structural schematic of an embodiment according to the present disclosure with the cover board closed; 
           [0025]      FIG. 2  is a structural schematic of an embodiment according to the present disclosure with the cover board open; 
           [0026]      FIG. 3  is a structural schematic of an embodiment according to the present disclosure with the cover board reslided; 
           [0027]      FIG. 4  is a structural schematic of the baseboard in an embodiment according to the present disclosure; 
           [0028]      FIG. 5  is a structural schematic of the front board in an embodiment according to the present disclosure; 
           [0029]      FIG. 6  is a structural schematic of the rear board in an embodiment according to the present disclosure; 
           [0030]      FIG. 7  is a structural schematic of the left board in an embodiment according to the present disclosure; 
           [0031]      FIG. 8  is a structural schematic from another perspective of the left board in an embodiment according to the present disclosure; 
           [0032]      FIG. 6  is a structural schematic of the cover board in an embodiment according to the present disclosure; 
           [0033]      FIG. 10  is an enlarged schematic of the portion A in  FIG. 2 ; 
           [0034]      FIG. 11  is an enlarged schematic of the portion B in  FIG. 3 ; 
           [0035]      FIG. 12  is an enlarged schematic of the portion C in  FIG. 4 ; 
           [0036]      FIG. 13  is an enlarged schematic of the portion D in  FIG. 5 ; 
           [0037]      FIG. 14  is an enlarged schematic of the portion E in  FIG. 6 ; 
           [0038]      FIG. 15  is an enlarged schematic of the portion F in  FIG. 6 ; 
           [0039]      FIG. 16  is an enlarged schematic of the portion G in  FIG. 7 ; 
           [0040]      FIG. 17  is an enlarged schematic of the portion H in  FIG. 8 ; and 
           [0041]      FIG. 18  is an enlarged schematic of the portion I in  FIG. 9 . 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0042]    The present disclosure will be described in further details below with reference to embodiments as shown in the attached figures. 
         [0043]    As shown in  FIGS. 1 to 3 , the box provided in the present embodiment comprises a baseboard  1 , a front board  2 , a rear board  3 , a left board  4 , a right board  5 , and a cover board  6 . An insert-connection structure capable of forming an insert connection with a respective adjacent board is integrally formed on each of the baseboard  1 , the front board  2 , the rear board  3 , the left board  4 , and the right board  5 . Moreover, any three perpendicular boards of the baseboard  1 , the front board  2 , the rear board  3 , the left board  4 , and the right board  5  are capable of forming an interlocking structure among them. That is, after the assembly is completed, the baseboard  1 , the front board  2 , the rear board  3 , the left board  4 , and the right board  5  cannot have relative movement. A connection structure capable of coupling with each other is integrally formed on each of the cover board  6  and the rear board  3 . Furthermore, the baseboard  1 , the front board  2 , the rear board  3 , the left board  4 , the right board  5 , and the cover board  6  are blow molding boards. The front board  2 , the rear board  3 , the left board  4 , the right board  5 , and the cover board  6  have plaited structure formed on their external surfaces. The bottom of the baseboard  1  has crisscrossed dot structure. In this way, the structural strength of the baseboard can be improved. 
         [0044]    In the present embodiment, the left board  4  and the right board  5  have the same structure. Accordingly, the assembling configurations of the left board  4  and the right board  5  are the same. The assembling configuration of the left board will be described below as an example. 
         [0045]    As shown in  FIGS. 4 to 18 , the assembling configuration of the left board  4  and the baseboard  1  is as follows. A horizontal retaining groove  7  of a front-rear direction with an inward opening is formed at the bottom of the left board  4 . In the present embodiment, the horizontal retaining groove  7  is a T-shape groove with the rear end closed. A horizontal rib  8  of a front-rear direction capable of forming an insert connection with the horizontal retaining groove  7  is formed on the left side of the baseboard  1 . Consequentially, a first insert-connection structure is formed between the left board  4  and the baseboard  1 , limiting the left board  4  to only slide frontward and backward relative to the baseboard  1 . During installation, the left board  4  is inserted onto the baseboard  1  in a front-rear direction. The left board  4  is installed in place when the closed ends of the horizontal rib  8  and the horizontal retaining groove  7  abut on each other. 
         [0046]    The assembling configuration of the left board  4  and the front board  2  is as follows. A vertical retaining groove  9  of an up-down direction with an inward opening is formed at each of the front and rear sides of the left board  4 . In the present embodiment, the vertical retaining groove  9  is a T-shape groove with the rear end closed. A vertical rib  10  along an up-down direction capable of forming an insert connection with the vertical retaining groove  9  is formed at each of the front and rear sides of the front board  2 . In this way, when the insertion connection between the left board  4  and the front board  2  is completed, a second insert-connection structure is formed between the left board  4  and the front board  2 , preventing the left board  4  to slide frontward and backward. Moreover, a lower step  11  is formed at both front and rear sides at the top portion of the left board  4 . The upper end of the vertical retaining groove  9  opens to the corresponding lower step  11 . A lug  12  protruding from the vertical rib  10  is formed at both front and rear sides at the top portion of the front board  2 . During installation, the front board  2  is inserted into the left board  4  in an up-down direction. The front board  2  is installed in place when the lower ends of the vertical rib  10  and the vertical retaining groove  9  abut on each other. Meanwhile, the lug  12  is pushed against the lower step  11  to prevent the left board  4  from moving upward. The installation configurations of the left board  4  and the rear board  3  may be considered by referring to the installation configurations of the left board  4  and the front board  2  and will not be explained in details here. 
         [0047]    The assembling configuration of the front board  2  and the baseboard  1  is as follows. An insert slot  13  and strip-shaped groove  15 , with each of the quantity being at least two, are provided alternately of a left-right direction at both the front and rear sides of the baseboard  1 . Pin  14  and bar-shaped rib  16  are formed alternately in a left-right direction at the bottom of the front board  2 . Each pin  14  corresponds to an insert slot  13  and each bar-shaped rib  16  corresponds to a strip-shaped groove  15  in with one-to-one correspondence. During installation, a pin  14  is inserted into the corresponding insert slot  13 , while a bar-shaped rib  16  is inserted into the corresponding strip-shaped groove  15 . Moreover, a buckling portion  141  bending inward is formed at the bottom of the pin  14 . When a pin  14  is inserted into an insert slot  13 , the buckling portion  141  is buckled reversely on the internal edge of the insert slot  13 , thus preventing the front board  2  from being lift upward. In this way, a third insert-connection structure that can prevent the displacement of the front board  2  relative to the baseboard  1  is formed by the inserted mating between the pin  14  and the insert slot  13 . In addition, there is no gap remaining viewable at the insert slot  13  from inside the box. The installation configuration between the rear board  3  and the baseboard  1  is the same as that of the front board  2  and the baseboard  1 , and will not be explained in details herein. 
         [0048]    The connection structure between the rear board  3  and the cover board  6  is a rotatable hinge structure. Specifically, the hinge structure comprises a hinge shaft  21 , a hinge arm  22 , and a hinge mount  23 . The hinge shaft  21  and the hinge mount  23  are formed integrally at the top portion of the rear board  3 , and the hinge arm  22  is formed on the rear lateral portion of the cover board  6 . A mating structure that only allows the hinge arm  22  to fit into or detach from the hinge shaft  21  in a certain direction is formed between the hinge shaft  21  and the hinge arm  22 . 
         [0049]    According to some embodiments, a plurality of hinge shafts  21  and hinge mounts  23  are alternately provided on the rear board  3 . The mating structure of the hinge shaft  21  and the hinge arm  22  is as follows. The hinge shaft  21  is a circular shaft with two lower cut faces  211  and an upper cut face  212  formed along the axial direction of the hinge shaft, the lower cut faces  211  and the upper cut face  212  being alternately provided in a horizontal plane. The hinge arm  22  comprises an upper arc-shaped embracing arm  221  and a lower arc-shaped embracing arm  222  that are axially staggered in an up-down direction. The vertical distance between the opposite edges of the upper arc-shaped embracing arm  221  and the lower arc-shaped embracing arm  222  is larger than the vertical distance between the lower cut faces  211  and the upper cut face  212  but smaller than the diameter of the hinge shaft  21 . In this way, the cover board  6 , when being installed to the rear board  3 , can only be installed onto the rear board  3  from a direction perpendicular with the rear board  3 , and can be installed onto the rear board  3  by rotating a certain angle after insertion. During disassembly of the cover board  6 , the cover board  6  can only be detached after being rotated to a perpendicular position with the rear board  3 . 
         [0050]    According to some embodiments, a water baffle edge  17  is formed at the top portion of each of front board  2 , the rear board  3 , the left board  4  and the right board  5 . A water baffle groove  18  is formed surrounding the bottom surface of the cover board  6 . The water baffle edge  17  fits into the water baffle groove  18  when the cover board  6  is closed so that the box is waterproof. Meanwhile, the water baffle edge  17  and the water baffle groove  18  are configured to limit displacement. In particular, the internal wall of the water baffle groove  18  formed at each of the left and right sides on the bottom surface of the cover board constitutes a solid reinforcing rib  181 , which abuts on the internal wall of the corresponding water baffle edge  17 . In this way, it is possible to effectively prevent deformation of the left board  4  and the right board  5  in the portion close to their upper edges when being pushed inward. In addition, the cover board  6  of the present embodiment is designed to be an arch-shaped structure that rises in the middle with both front and rear sides lowered. In this way, the structural and bearing strength of the cover board  6  are improved so that deformation is not easily caused by irradiation or rain, while the rain fallen onto the cover board  6  can be readily guided away from the cover board. Furthermore, to prevent displacement of the cover board  6  after closing, two lugs  19  are formed at the top portion of each of the left board  4  and the right board  5 , while a groove  20  is provided in a corresponding location at each of the left and right sides at the bottom of the cover board  6 . The lug  19  fits into the corresponding groove  20  when the cover board  6  is closed. 
         [0051]    According to some embodiments, to match the arched structure of the cover board  6 , a first baffle bar  24  in a left-right direction is formed at each of the front and rear sides of the internal bottom surface of the baseboard  1  and a second baffle bar  25  in a front-rear direction is formed at each of the left and right sides of the internal bottom surface of the baseboard  1 . The upper end face of the second baffle bar  25  has an arc shape that is concaved inward from both ends to the middle. The middle portion of the second baffle bar  25  and the internal bottom surface of the baseboard  1  that is adjacent to this middle portion together define a inward concave regain. Moreover, the arc of the arc structure of the second baffle bar  25  and the inward concavity of the aforementioned concave region match with the arch shape of the cover board  6 . Accordingly, the inward concave structure on the baseboard can match the arch shape of the cover board  6 . During packing of the box, the cover board  6  may be stacked onto the internal bottom surface of the baseboard  1  with the top surface facing down so that the package volume is advantageously reduced. According to some embodiments, a water baffle rib  26  is formed inside the region between the first baffle bar  24  and the second baffle bar  25 , and a water guide groove  27  is provided at the joint of the first baffle bar  24  and the second baffle bar  25 . With the water guide groove  27 , it can effectively prevent water accumulation in the box. With the water baffle rib  26 , it further protects stored items when there is a small amount of water collected in the box. 
         [0052]    To fix the box on the ground, a fixing pin  28  with a mounting hole  281  is formed at the bottom of each of the left board  4  and the right board  5 , protruding therefrom horizontally. Moreover, a limiting groove  29  is formed on the internal bottom surface of the cover board  6 . During packing, when the left board  4  and the right board  5  are stacked with the top surface facing down onto the internal bottom surface of the cover board  6 , the fixing pin  28  can be stored tightly in the limiting groove  29  so that it does not take additional package volume. 
         [0053]    According to some embodiments, a reinforcing bar  30  in a left-right direction is fixed onto the front bottom of the cover board  6 . The use of reinforcing bar  30  can improve the structural strength of the cover board. A lock latch  31  extending downward is formed in the middle of the reinforcing bar  30 . A recess portion  32  that is sunken inward is formed on the external surface of the front board  2 , close to the upper edge. A lock hole  33  matching the lock latch  31  is provided on the recess portion  32 . Moreover, a guide ramp  34  is formed on the internal surface of the front board corresponding to the recess portion  32 . The guide ramp  34  is above the lock hole  33 . When the cover board is closed, the lock latch  31  gets in touch with the guide ramp  34  and comes to fit into the lock hole  33 . 
         [0054]    During packing, the baseboard  1  is first laid flat with the bottom surface facing downward and the cover board  6  is stacked onto the baseboard  1  with the top surface facing downward. Then, the left board  4  and the right board  5  are stacked at each of the left and right sides of the cover board  6 , with their external surfaces facing downward. Finally, the front board  2  and the rear board  3 , with their external surfaces facing downward, are stacked successively on top of the left board  4  and the right board  5 . When packing is completed, the lock latch  31  faces upward and abuts right on the top edge of the front board  2 , and a retaining structure for receiving the hinge mount  23  and the hinge shaft  21  of the rear board  3  is formed between the bottom edge of the front board  2  and the rear edge of the cover board  6 , so that the protruding hinge mount  23  and hinge shaft  21  may not occupy extra package volume. When packing is completed, it is possible to prevent the respective board from sliding as well as make full use of the space so that the package volume is reduced. 
         [0055]    The embodiments described above are only some of the preferred embodiments of the present disclosure. It would be understood by a person skilled in the art that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present disclosure. Such changes and modifications should be considered as within the protection scope claimed by the present disclosure.