Abstract:
A wafer container is constructed to include a shell, a holder frame, two retaining blocks, and a handle. The shell has a coupling unit at the periphery. The retaining blocks are fastened to the holder frame, forming first pivot structure. The handle is provided with second pivot structure adapted for coupling to the first pivot structure for enabling the handle to be turned relative to the holder frame through an angle between the operative position convenient for carrying by hand, and the collapsed, non-operative position to minimize space occupation.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of The Invention 
     The present invention relates to wafer containers adapted for carrying wafers, and more particularly to wafer containers, which have retractable handle structure convenient for carrying by hands. 
     2. Description of Related Art 
     Regular wafer containers may be designed for carrying by hand or using a mechanical arm. U.S. Pat. No. 5,788,082 and U.S. Pat. No. 5,944,194 disclose wafer container handles convenient for carrying by hands. Because the handles protrude from the periphery of the wafer container at two opposite sides at a distance, much floor space is required when arranging multiple wafer containers in parallel in a clean room. 
     SUMMARY OF THE INVENTION 
     It is the main object of the present invention to provide wafer containers with retractable handles, so that such wafer containers can be arranged in a smaller space. 
     It is another object of the present invention to provide wafer containers with retractable handles which are detachable, and easily made up. 
     To achieve these and other objects of the present invention, there is provided a wafer container, which comprises a shell having at least one coupling unit at the periphery thereof, a holder frame adapted for coupling to the coupling unit of the shell, at least one retaining block adapted for fastening to the holder frame to form a first pivot structure, and at least one handle adapted for coupling to the first pivot structure. The handle is provided with a second pivot structure adapted for coupling to the first pivot structure for enabling the handle to be respectively turned relative to the holder frame through an angle between the operative position and the collapsed, non-operative position. 
     The holder frame, the retaining block, the handle and the shell can be separately made and then coupled to one another. 
     Alternatively, the holder frame and the retaining block can be made into a whole, and then coupled to the shell to hold the handle. The retaining block can be fastened to a respective coupling groove at the holder frame by press-fitting, hook means, snap means, screw means, or any equipment fastening means. 
     First and second positioning means may be provided to hold the handle between the operative position and the non-operative position. The first pivot structure an d the second pivot structure can be pivot holes and pivot axles, through holes and pins, or any other equivalent coupling structure that enables the handle to be turned relative to the holder frame. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a wafer container constructed according to the present invention. 
     FIG. 2 is an exploded view of the present invention. 
     FIG. 3 is a section view in an enlarged scale taken along line A—A of FIG.  1 . 
     FIG. 4 is a section view showing the handle set in the first position according to the present invention. 
     FIG. 5 is a section view showing the handle set in the second position according to the present invention. 
     FIG. 6 shows multiple wafer containers arranged in a line according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIG. 1, at each of two sidewalls  10  and  10 ′ of the shell  1  of a wafer container, there is provided a handle holder. The two handle holders may be respectively formed integral with the sidewalls  10  and  10 ′. According to the present preferred embodiment, the handle holders, referenced by  3 , are made retractable. 
     Referring to FIG.  2  and FIG. 1 again, each retractable handle holder  3  forms with a handle  2  a retractable operation handle. The handle holder  3  comprises holder frame  30 , and two retaining blocks  32 . During the assembly process, the handle  2  is put in the holder frame  30 , and then the retaining blocks  32  are inserted into the holder frame  30 , and then the holder frame  30  is coupled to the shell  1 , enabling two distal ends of the handle  2  to be respectively pivoted to the handle holder  3 . Alternatively, the holder frame and the retaining blocks can be integrally made and then coupled to the shell. The holder frame  30  is a substantially U-shaped member comprising two openings  31  at two opposite ends, each opening  31  having a middle hole  311  adapted to receive the retaining blocks  32  and the ends of the handle  2 , two symmetrical pairs of recessed portions  312  respectively bilaterally disposed in the openings  31 , two notches  313  respectively disposed in the openings  31  at a bottom side, and two symmetrical pairs of semicircular long grooves  310  respectively bilaterally disposed in the openings near a rear side remote from the notches  313 . The semicircular long grooves  310  each have a smoothly arched inner end. The retaining blocks  32  fit the openings  31 , and are respectively inserted into the openings  31  from a back side. Each retaining block  30  comprises two arches  320  adapted for inserting into the semicircular long grooves  310 , and a resilient plate  322 . The resilient plate  322  has a rib  321 . The arches  320  each have a notched front end. When press-fitting the retaining blocks  32  in a respective surround groove  330  at the back side wall of the holder frame  30  around each opening  31 , the notched front end of each arch  320  forms with the smoothly arched inner end of the corresponding groove  310  a first pivot structure  11 . According to the present preferred embodiment, the first pivot structure  11  is a pivot hole  33 . 
     The handle  2  is a substantially U-shaped member having two pivot structures, namely, pivot axles  21  disposed at two distal ends thereof. Before the installation of the retaining blocks  32 , the pivot axles  21  are inserted with the two distal ends of the handle  2  through the recessed portions  312  and notches  313  of the openings  31  from the front side of the holder frame  30  to the back side thereof, and then the handle  2  is moved upwards and then forwards, enabling the pivot axles  21  to be respectively moved into the grooves  310  and respectively stopped at the smoothly arched inner end of each groove  310 . Then the retaining blocks  32  are respectively press-fitted into the respective surround grooves  330  to hold the pivot axles  21  of the handle  2  in the respective pivot holes  33 . After installation of the retaining blocks  32  in the holder frame  30 , the back side wall of the holder frame  30  and the back side wall of each retaining block  32  are flush for mounting on one side wall  10  of the shell  1 . The pivot axles  21  form a revolving shaft  110  disposed in parallel to the sidewall  10  of the shell  1  and rotatable in the pivot holes  33 . By means of the aforesaid arrangement, the handle  2  is pivoted to the handle holder  3 . After installation of the handle  2  and the retaining blocks  32  in the handle holder  3 , two protruded resilient plates  34  of the holder frame  30  are respectively coupled to a pivot structure at the sidewall  10  of the shell  1 . According to the present preferred embodiment, the pivot structure at the sidewall  10  of the shell  1  is comprised of two parallel lugs  13  facing each other. The lugs  13  each define a long coupling groove  131 . When inserting the resilient plates  34  of the holder frame  30  into the coupling grooves  131 , a short back coupling groove  15  of the holder frame  30  is forced into engagement with a short coupling lug  14 , which is provided at the sidewall  10  of the shell  1  between the lugs  13 . By means of the aforesaid arrangement, the handle  2  can be easily detachably installed in one sidewall  10  of the shell  1  without the use of screws or fastening elements. 
     Referring to FIG.  3  and FIG. 2 again, the resilient plates  34  of the holder frame  30  each have free end terminating in a hooked portion  341  and a raised portion  342  on the middle. After coupling of the resilient plates  34  and coupling groove  15  of the holder frame  30  to the respectively coupling grooves  131  and short coupling lug  14  of the shell  1 , the hooked portions  341  of the resilient plates  34  are respectively hooked up with the top end  132  of each lug  13 . 
     Referring to FIG. 4, when wishing to carry the shell  1 , the handle  2  is turned outwards from the holder frame  30  to the first position shown in FIG. 4 convenient for carrying with the hand. At this time, the first locating groove, referenced by  221 , at each end of the handle  2  is respectively forced into engagement with the rib  321  at the resilient plate  322  of each retaining block  32 , keeping the handle  2  positively held in the first position. At the same time, two protruding portions  343  and the coupling strip  15  of the holder frame  30  are respectively stopped at the bottom end  133  of each lug  13  and the bottom end  141  of the short coupling lug  14 , enabling the shell  1  to be conveniently carried by hand. 
     Referring to FIG. 5, when not in use, the handle  2  is turned downwards to the second position shown in FIG.  5  and closely attached to the sidewall  10  of the shell  1 . At this time, the second locating groove  222  at each end of the handle  2  is respectively forced into engagement with the rib  321  at the resilient plate  322  of each retaining block  32 , keeping the handle  2  positively held in the second position. 
     Referring to FIG. 6, when several container bodies  1  (wafer containers) are put together in a line, less floor space is required. Because the handle  2  of each wafer container is set in the second position, the distance d between each two adjacent container bodies  1  is minimized, and many wafer containers can be stored in a limited storage space. 
     It is to be understood that the drawings are designed for purposes of illustration only, and are not intended for use as a definition of the limits and scope of the invention disclosed.