Abstract:
A combination drawer assembly includes a combination drawer holder and one or a number of basket drawers. The combination drawer holder includes a bottom frame, and two support frames connected to the bottom frame in parallel. The support frames provide horizontally aligned seat tracks. Each basket drawer is slidably mounted in two horizontally aligned seat tracks, and prohibited by the respective seat tracks from falling out of the combination drawer holder.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a combination drawer structure, and more particularly to a combination drawer assembly that prohibits basket drawers from being pulled away from the combination drawer holder. The invention relates also to the assembly method of the combination drawer assembly. 
     2. Description of the Related Art 
     U.S. Pat. Nos. 7,270,245 and 6,508,376 disclose two different designs of combination drawer systems. In actual practice, combination drawer systems facilitate delivery and save transportation cost. However, according to these two patents, the drawer can easily be pulled away from the drawer holder. Thus, the storage materials or files can fall out of the drawer accidentally, causing trouble. 
     SUMMARY OF THE INVENTION 
     The present invention has been accomplished under the circumstances in view. It is the main object of the present invention to provide a combination drawer assembly, which comprises a combination drawer holder and at least one basket drawer. The combination drawer holder comprises a bottom frame and two support frames connected to the bottom frame in parallel. Each support frame comprises a front tube, a rear tube, and at least one seat track connected between the front tube and the rear tube. Each seat track of one support frame is kept in horizontal alignment with one respective seat track of the other support frame. Each seat track comprises a position-limit rod member and a support rod member disposed at different elevations and kept in vertical alignment. The support rod member comprises a downwardly curved recessed portion. Each basket drawer is slidably mounted in the combination drawer holder. Each basket drawer comprises a basket drawer body, two rails and two balls. The rails are respectively connected to two opposite lateral walls of the basket drawer body, and respectively positioned in between the position-limit rod member and support rod member of one respective seat track of each of the two support frames. The two balls are respectively connected to the two rails and disposed at a bottom side relative to the two rails. The two balls are respectively inserted through the downwardly curved recessed portions of the support rod members of the respective seat tracks and disposed at an outer side relative to the two support rod members. 
     When compared to the prior art design, the basket drawers of the combination drawer assembly are stopped by the position-limit rod members of the respective seat tracks from upward displacement to escape from the respective seat tracks. Further, the arrangement of the two balls of each basket drawer and the support rod members of the respective seat track prevents the basket drawer from being separated from the combination drawer holder. Therefore, the combination drawer assembly of the present invention can prohibit the basket drawers from being moved away from the combination drawer holder. 
     The invention also provides a method of assembling a combination drawer assembly that comprises a first step of providing a combination drawer holder and at least one basket drawer. The combination drawer holder comprises a bottom frame and two support frames. The bottom frame comprises a front rod member and a rear rod member. The front rod member has two opposite ends thereof respectively bent in one direction through a predetermined angle to form one respective upright end portion. The rear rod member has two opposite ends thereof respectively bent in one direction through a predetermined angle to form one respective upright end portion. Each support frame comprises a front tube, a rear tube, and at least one seat track connected between the front tube and the rear tube. Each seat track comprises a position-limit rod member and a support rod member disposed at different elevations and vertically kept in alignment. The support rod member comprises a downwardly curved recessed portion. The basket drawer comprises a basket drawer body, two rails and two balls. The two rails are connected to two opposite lateral sides of the basket drawer body. The two balls are respectively connected to the rails and disposed at a bottom side relative to the rails. Thereafter, a send step is proceeded to press-fit the front tubes and the rear tubes of the support frames onto the upright end portions of the front rod member and rear rod, member of the bottom frame, keeping each seat track of one support frame in horizontal alignment with one respective seat track of the other support frame. Thereafter, proceed to the final step of enabling the two balls of each basket drawer to pass through the downwardly curved recessed portions of the support rod members of two horizontally aligned seat tracks by means of the resilience between the support frames and the bottom frame so as to let the two rails of each basket drawer be positioned in between the position-limit rod member and support rod member of each of the two horizontally aligned seat tracks. 
     Other advantages and features of the present invention will be fully understood by reference to the following specification in conjunction with the accompanying drawings, in which like reference signs denote like components of structure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded view of a combination drawer holder for combination drawer assembly in accordance with the present invention. 
         FIG. 2  is an perspective view of a basket drawer for combination drawer assembly in accordance with the present invention. 
         FIG. 3  is a sectional view taken along line A-A of  FIG. 2   
         FIG. 4  is a schematic assembly view of the bottom frame and the two support frame shown in  FIG. 1 . 
         FIGS. 5-8  illustrate the assembly method of the basket drawer shown in  FIG. 2 . 
         FIG. 9  is an oblique top plan view of the combination drawer assembly. 
         FIG. 10  corresponds to  FIG. 9 , illustrating a status of use of the combination drawer assembly. 
         FIG. 11  is a side view of the combination drawer assembly shown in  FIG. 10 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A combination drawer assembly comprises a combination drawer holder and at least one basket drawer. Referring to  FIG. 1 , the combination drawer holder  20  comprises a bottom frame  21 , two support frames  22 ,  23 , and a top frame  24 . The bottom frame  21  comprises a front rod member  25 , a rear rod member  26 , and two connection rod members  27 . These rod members are preferably made of metal. In this embodiment, the front rod member  25  has the opposing left and right ends thereof respectively bent upward, forming a respective upright end portion  251 ,  252 . The rear rod member  26  has the opposing left and right ends thereof respectively bent upward, forming a respective upright end portion  261 ,  262 . Each the connection rod members  27  have the respective opposing front and rear ends thereof respectively connected to the front rod member  25  and the rear rod member  26 . The two connection rod members  27  are parallel manner. Preferably, the connection rod members  27  are connected to the front rod member  25  and the rear rod member  26  by welding. 
     The two support frames  22 ,  23  are identical, each comprising a front tube  28 ,  29 , a rear tube  30 ,  31 , and three seat tracks  32 - 34 ,  35 - 37 . The front tube  28 ,  29  and the rear tube  30 ,  31  are preferably metal tubes. The front tube  28 ,  29  and rear tube  30 ,  31  of the two support frames  22 ,  23  are respectively and press-fitted onto the upright end portion  251 ,  252 ,  261 ,  262  of the front and rear rod members  25 ,  26 . The three seat tracks  32 - 34 ,  35 - 37  are identical in structure, having the respective opposing front and rear ends thereof respectively fixedly connected to the front tube  28 ,  29  and the rear tube  30 ,  31  to hold the front tube  28 ,  29  and the rear tube  30 ,  31  in vertical and in a parallel manner. Because the three seat tracks  32 - 34 ,  35 - 37  are identical in structure and respectively connected to the front tube  28 ,  29  and the rear tube  30 ,  31  in the same manner, only the seat track  32  is taken as an example for explanation. The seat track  32  comprises a rod member  38 , and a support rod member  39  disposed at different elevations and kept in vertical alignment. The position-limit rod member  38  and the support rod member  39  are preferably metal rod members. The position-limit rod member  38  is spaced above the support rod member  39 , defining a gap G with the support rod member  39  therebetween. 
     The support rod member  39  has a middle part thereof curved down and up to form a recessed portion  40 , and opposing front and rear ends thereof bent in one direction through a predetermined angle to form a respective connection end portion  41 . The two connection end portions  41  of the support rod member  39  are respectively fixedly connected to the front tube  28  and rear tube  30  of the respective support frame  22  by, preferably, welding. In this embodiment, the recessed portion  40  is disposed relatively closer to the front tube  28 . However, in actual application, the location of the recessed portion  40  is not limited to the illustration. 
     The top frame  24  is adapted to connect the two support frames  22 ,  23 . The top frame  24  comprises two top rod members  43 ,  44 . The two top rod members  43 ,  44  are preferably metal rods. Each top rod member  43 ,  44  has the opposing left and right ends respectively bent in one direction through a predetermined angle to form a respective perpendicular end portion  431 ,  432 ,  441 ,  442 . The two perpendicular end portions  431 ,  432  of the top rod member  43  are respectively press-fitted into the front tubes  28 ,  29  of the two support frames  22 ,  23  opposite to the front rod member  25 . The two perpendicular end portions  441 ,  442  of the top rod member  44  are respectively press-fitted into the rear tube  30 ,  31  of the two support frames  22 ,  23  opposite to the rear rod member  26 . 
     Referring to  FIGS. 2 and 3 , each basket drawer  50  comprises a basket drawer body  51 , two rails  52 ,  53 , and two balls  54 ,  55 . The inside wall of the basket drawer body  51  defines an accommodation open chamber for accommodating document, stationery, books, magazines, and the like. The two rails  52 ,  53  are respectively connected to two opposite lateral sides of the basket drawer body  51  and disposed at a top side of the basket drawer body  51 . The two balls  54 ,  55  are respectively connected to the two rails  52 ,  53  and disposed at a bottom side. In this embodiment, the basket drawer body  51  and the two rails  52 ,  53  are integrally made in one piece. Preferably, metal, plastic or acrylic is selected for making the basket drawer body  51  and the two rails  52 ,  53 . The two balls  54 , 55  are respectively connected to the two rails  52 ,  53  by welding or bonding. 
     Referring to  FIG. 4 , when assembling the combination drawer assembly, attach the two support frames  22 ,  23  to the bottom frame  21 , i.e., press-fit the front tubes  28 ,  29  and rear tubes  30 ,  31  of the two support frames  22 ,  23  onto the upright end portion  251 ,  252 ,  261 ,  262  of the front and rear rod members  25 ,  26  respectively. 
     Referring to  FIG. 5 , after the two support frames  22 ,  23  and the bottom frame  21  are well assembled, the three seat tracks  32 - 34  of one support frame  22  are respectively and horizontally kept in alignment with the respective seat tracks  35 - 37  of the other support frame  23 . In this embodiment, multiple basket drawers  50  having the same width and height are used. The width means the distance between the two rails  52 ,  53 . The height means the depth of the accommodation open chamber defined in each basket drawer  50 . The basket drawers  50  can be installed in the support frames  22 ,  23 . 
     Referring to  FIGS. 6-8 , the procedure of the installation of one basket drawer  50  in the support frames  22 ,  23  is shown, wherein the combination drawer holder  20  is illustrated in a sectional view taken along line B-B of  FIG. 5 . As illustrated in  FIG. 6 , insert one rail  53  of the basket drawer  50  obliquely in between the position-limit rod member  38   a  and support rod member  39   a  of the seat track  37  of One support frame  23 . to force the respective ball  55  through the recessed portion  40   a  of the support rod member  39   a . Thereafter, as shown in  FIG. 7 , impart an outward pressure to the upper part of the other support frame  22  to elastically deform the combination drawer holder  20  subject to the resilient material property of the bottom frame  21  and the support frames  22 ,  23 , enabling the other ball  54  of the basket drawer  50  to face toward the recessed portion  40   b  of the support rod member  39   b  of the seat track  34  of the other support frame  22 . Finally, as shown in  FIG. 8 , release the pressure from the other support frame  22  after alignment between other ball  542  of the basket drawer  50  and the recessed portion  40   b  of the support rod member  39   b  of the seat track  34  of the other support frame  22 , enabling the other support frame  22  to return to its former position. At this time, the other ball  54  of the basket drawer  50  passes through the recessed portion  40   b  of the support rod member  39   b  of the seat track  34  of the other support frame  22 , and thus the basket drawer  50  is accurately installed in the support frames  22 ,  23 , wherein the basket drawer body  51  of the basket drawer  50  is kept in between the two support rod members  39   a ,  39   b.    
     Referring to  FIG. 8  again, after installation of the basket drawer  50  in the support frames  22 ,  23 , the two rails  52 ,  53  of the basket drawer  50  are respectively positioned in between the two position-limit rod members  38   a ,  38   b  and the two support rod members  39   a ,  39   b , and the two balls  54 ,  55  are respectively disposed at an outer side relative to the support rod members  39   a ,  39   b . Thus, the position-limit rod members  38   a ,  38   b  prohibit the basket drawer  50  from upward displacement. Because the two balls  54 ,  55  are respectively stopped at an outer side of the support rod members  39   a ,  39   b , the basket drawer  50  is prohibited from escaping out of the support frames  22 ,  23 . 
     Based on what is stated above we know that the basket drawer  50  can be accurately installed in the support frames  22 ,  23 . The other two basket drawers can be installed in the combination drawer holder in the same manner, and therefore the installation of the other two basket drawers will not be described further. 
     Referring to  FIG. 9 , after installation of all basket drawers  50  in the support frames  22 ,  23 , the perpendicular end portions  431 ,  432 ,  441 ,  442  of the top rod members  43 ,  44  are respectively press-fitted into the front tubes  28 ,  29  and rear tube  30 ,  31  of the two support frames  22 ,  23 , enabling the top rod members  43 ,  44  to be supported on the support frames  22 ,  23 . Thus, the combination drawer assembly  10  is completely assembled. Based on what is stated above we know that the combination drawer assembly  10  can easily be assembled. Further, during delivery, the component parts of the combination drawer holder  20  and the basket drawers  50  can be separately packed, for example, multiple bottom frames  21  and multiple support frames  23  can be packed in one package, and multiple top rod members  43 ,  44  and multiple basket drawers  50  are separately packed in other packages. 
     Referring to  FIG. 10  and  FIG. 9  again, these basket drawers  50  can be pulled forwards relative to the combination drawer holder  20  to an extended position (see  FIG. 10 ) and pushed backwards relative to the combination drawer holder  20  to a retracted position (see  FIG. 9 ). It should be ted that when the basket drawer  50  is pulled to the extended position, the basket drawer  50  does not fall out of the combination drawer hold  20 . 
     Referring to  FIG. 11 , when the basket drawer  50  is pulled out of the combination drawer holder  20  to the extent, the balls  55  of the basket drawer  50  will be stopped by the connection end portions  41  of the support rod members  39 , prohibiting the basket drawer  50  from being directly separated from the combination drawer holder  20 . Actually, the front tubes  28 ,  29  of the two support frames  22 ,  23  can also stop the balls  50  from forward movement, and therefore the work of stopping the balls  50  is not limited to the connection end portions  41  of the support rod members  39 . 
     It is to be noted that, in the preferred embodiment of the invention described above, the combination drawer holder consists of the said bottom frame, the said support frames and the said top frame, however, in actual practice, the front and rear tubes of the support frames can be the extensions of thee upright end portions of the front and rear rod members of bottom frame, i.e., the front tubes of the support frames are respectively formed integral with the front rod member of the bottom frame and, the rear tubes of the support frames are respectively formed integral with the rear rod member of the bottom frame. Therefore, the structural features of the bottom frame and the support frames are not limited to the above-described preferred embodiment. 
     Further, in the above-described preferred embodiment of the present invention, the basket drawers have the same width and height, however, in actual application, these basket drawers can be made having different heights. Therefore, the above-described preferred embodiment should not be regarded as limitations of the present invention. Further, in the above-described preferred embodiment of the present invention, the combination drawer assembly is a three-level design, however, this three-level design is not intended to be interpreted a limitation of the present invention. Alternatively, the combination drawer assembly can be a single level or two-level design, or a design more than three levels.