Abstract:
An exemplary rotation module configured for a gantry apparatus includes a rotary plate, a base, and a bearing. The rotary plate has a through hole. The base is arranged in the through hole. The bearing is arranged between the rotary plate and the base. The bearing includes an inner race and an outer race rotatable relative to the inner race. The inner race is securely coupled to the base and the outer race is securely coupled to the rotary plate, whereby the rotary plate is rotatable relative to the base. A gantry apparatus are also provided.

Description:
TECHNICAL FIELD 
     The present invention relates to gantry apparatuses, and more particularly to a rotatable supporting module for a gantry apparatus and a gantry apparatus having the rotatable supporting module that can prevent a cross bar thereof from being damaged. 
     DESCRIPTION OF RELATED ART 
     Gantry apparatuses are becoming widely used. Referring to  FIG. 8 , a gantry apparatus  1  in accordance with a related art is shown. The apparatus  1  includes a left guideway  2 , a right guideway  3 , a cross bar  4  having two opposite ends, a left slider  5  arranged on the left guideway  2 , a right slider  6  arranged on the right guideway  3 , a left driver  7 , and a right driver  8 . One end of the cross bar  4  is mounted on the left slider  5  and the other end of the cross bar  4  is mounted on the right slider  6 . The left slider  5  is driven by the left driver  7  thereby moving the cross bar  4  along the left guideway  2 . The right slider  6  is driven by the right driver  8  thereby moving the cross bar  4  along the right guideway  3 . When the left slider  5  moves non-synchronously with the right slider  6 , the cross bar  4  will tilt and be damaged. 
     What is needed, therefore, is a rotatable supporting module and a gantry apparatus having same that can prevent a cross bar thereof being damaged. 
     SUMMARY 
     In an embodiment, a rotatable supporting module configured (i.e., structured and arranged) for a gantry apparatus includes a rotary plate, a base, and a bearing. The rotary plate has a through hole. The base is arranged in the through hole. The bearing is arranged between the rotary plate and the base. The bearing includes an inner race and an outer race rotatable relative to the inner race. The inner race is securely coupled to the base and the outer race is securely coupled to the rotary plate, thus allowing the rotary plate to be rotatable relative to the base. 
     In another embodiment, a gantry apparatus includes a first guideway and a second guideway arranged parallel with each other, the rotatable supporting module mounted on the first guideway, a slidable and rotatable supporting module slidably mounted on the second guideway, and a cross bar having opposite ends mounted on the rotatable supporting module and the slidable and rotatable supporting module. The slidable and rotatable supporting module includes the rotatable supporting module, and a slidable plate, and a sliding bearing. The sliding bearing includes a first elongated part and a second elongated part juxtaposed with each other. The first elongated part is slidably engaged with the second elongated part and the first elongated part is securely coupled to the rotary plate. The second elongated part is securely coupled to the slidable plate, whereby the slidable plate is slidable along a lengthwise direction of the sliding bearing. 
     Other advantages and novel features will become more apparent from the following detailed description of the present rotatable supporting module and gantry apparatus having same when taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present invention. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
         FIG. 1  is an isometric view of a rotatable supporting module in accordance with a first embodiment. 
         FIG. 2  is a cross-sectional view of the rotatable supporting module, taken along the line  11 - 11  shown in  FIG. 1 . 
         FIG. 3  is an exploded isometric view of the rotatable supporting module shown in  FIG. 1 . 
         FIG. 4  is an isometric view of a slidable and rotatable supporting module in accordance with a second embodiment. 
         FIG. 5  is a cross-sectional view of the slidable and rotatable supporting module, taken along the line V-V shown in  FIG. 4 . 
         FIG. 6  is an exploded isometric view of the slidable and rotatable supporting module shown in  FIG. 4 . 
         FIG. 7  is an isometric view of a gantry apparatus in accordance with a third embodiment. 
         FIG. 8  is an isometric view of a typical gantry apparatus. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     Reference will now be made to the drawing figures to describe the embodiments of the present rotatable supporting module and gantry apparatus with same in detail. 
     Referring to  FIGS. 1 to 3 , a rotatable supporting module  10  in accordance with a first embodiment is shown. The rotatable supporting module  10  includes a rotary plate  11 , a base  12 , a bearing  13 , a first holder  14 , a second holder  15 , a cover  17 , and two connecting blocks  19 . 
     The rotary plate  11  includes a through hole  110  defined therein, an inner flange  111 , and two opposite step portions  112 . The inner surface of the rotary plate  11  that defines the through hole  110  extends radially to form the flange  111 . Two opposite ends of the rotary plate  11  respectively define the two step portions  112 . 
     Each connecting block  19  has a plurality of bolt holes  191 . One of the connecting blocks  19  is mounted on one step portion  112  and the other connecting block  19  is mounted on the other step portion  112 . One end of a cross bar  43  having opposite two ends (shown in  FIG. 7 ) is connected to the rotary plate  11  through the connecting blocks  19  and some screws screwed into the bolt holes  191 . 
     The base  12  is a cylinder shape and is arranged in the through hole  110 . The outer surface of the base  12  extends radially to form a flange  121 . 
     The bearing  13  is arranged between the rotary plate  11  and the base  12 . The bearing  13  includes an inner race  131  and an outer race  132 . The inner race  131  is coaxially aligned with the outer race  132 . The inner race  131  is rotatable relative to the outer race  132 . The inner race  131  is arranged on the flange  121  and mounted on the base  12  through engagement between the first holder  14  and some screws  141 . The outer race  132  is arranged on the flange  111  and mounted on the rotary plate  11  through engagement between the second holder  15  and some screws  16 . Therefore, the rotary plate  11  can rotate around the base  12 . Thus, the cross bar  43  can rotate around the base  12 . 
     The cover  17  is held on the second holder  15  by some screws  18 . The cover  17  can prevent the dust outside falling into the rotatable supporting module  10 . 
     Referring to  FIGS. 4 to 6 , a slidable and rotatable supporting module  20  in accordance with a second embodiment is shown. The slidable and rotatable supporting module  20  includes a rotary plate  21 , a base  22 , a bearing  23 , a first holder  24 , a second holder  26 , a sliding bearing  28 , a slidable plate  29 , and a locking plate  32 . 
     The rotary plate  21  includes a through hole  210  defined therein and has a flange  211 . The inner surface of the rotary plate  21  that defines the through hole  210  extends radially to form the flange  211 . 
     The base  22  is a cylinder shape and is arranged in the through hole  210  and has a flange  221 . 
     The bearing  23  is arranged between the rotary plate  21  and the base  22 . The bearing  23  includes an inner race  231  and an outer race  232 . The inner race  231  is coaxially aligned with the outer race  232 . The inner race  231  is rotatable relative to the outer race  232 . The inner race  231  is arranged on the flange  221  and mounted on the base  22  through engagement between the first holder  24  and some screws  25 . The outer race  232  is arranged on the flange  211  and mounted on the rotary plate  21  through engagement between the second holder  26  and some screws  27 . Therefore, the rotary plate  21  can rotate around the base  22 . 
     The sliding bearing  28  is arranged between the slidable plate  29  and the rotary plate  21 . The sliding bearing  28  includes an inner member  281  and an outer member  282 . The inner member  281  is slidable relative to the outer slidable member  282 . The inner member  281  is mounted on the rotary plate  21  by some screws  30 . The outer member  282  is mounted on the slidable plate  29  by some screws  31 . Therefore, the slidable plate  29  can move lengthwise along the sliding bearing  28 . The inner member  281  does not touch the slidable plate  29 , thus there is little friction force between the inner member  281  and the slidable plate  29 . 
     The slidable plate  29  has a plurality of bolt holes  291  thereon and an inner sidewall  292  at the end thereof. The locking plate  32  locks the outer member  282  to the inner sidewall  292 , thus securely mounting the outer member  282  on the slidable plate  29 . The other end of the cross bar  43  (shown in  FIG. 7 ) is connected to the slidable plate  29  by some screws screwed into the bolt holes  291 . This allows the cross bar  43  to slide lengthwise along the sliding bearing  28  and rotate around the base  22 . 
     Referring to  FIG. 7 , a gantry apparatus  40  in accordance with a third embodiment is shown. The apparatus  40  includes the rotatable supporting module  10 , the slidable and rotatable supporting module  20 , a left guideway  41 , a right guideway  42  parallel with the left guideway  41 , and the cross bar  43 . 
     A left slider  44  is arranged on the left guideway  41  and the slidable and rotatable supporting module  20  is mounted thereon. A left driver  46  moves the slidable and rotatable supporting module  20  through the left slider  44 . One end of the cross bar  43  is mounted on the slidable and rotatable supporting module  20 . 
     A right slider  45  is arranged on the right guideway  42  and the rotatable supporting module  10  is mounted thereon. A right driver  47  moves the rotatable supporting module  10  through the right slider  45 . The other end of the cross bar  43  is mounted on the rotatable supporting module  10 . 
     The cross bar  43  can rotate around the rotatable supporting module  10  and slide along the sliding bearing  28  of the slidable and rotatable supporting module  20 . When the slidable and rotatable supporting module  20  moves with the rotatable supporting module  10  non-synchronously, the cross bar  43  slides a distance along the sliding bearing  28  of the slidable and rotatable supporting module  20  and rotates a small angle around the base  12  of the rotatable supporting module  10 . A torsion force that can damage the cross bar  43  is thus released. Thus, the cross bar  43  cannot be damaged. 
     Although the present invention has been described with reference to specific embodiments, it should be noted that the described embodiments are not necessarily exclusive, and that various changes and modifications may be made to the described embodiments without departing from the scope of the invention as defined by the appended claims.