Abstract:
An automatic support mechanism. The automatic support mechanism includes a fixed base, a first supporting member, a second supporting member and an extendable supporting member. The first supporting member is rotatably connected to the fixed base. The second supporting member is rotatably connected to the fixed base and is slidably connected to the first supporting member. The extendable supporting member is movably disposed between the first supporting member and the second supporting member. The extendable supporting member automatically moves between a received position and an extended position by relative rotation and sliding of the first and second supporting members.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to an automatic support mechanism, and in particular to an automatic support mechanism that is easy to operate.  
         [0003]     2. Description of the Related Art  
         [0004]     A printer or business machine usually includes a feeding device to input media sheets thereto. The media sheets are placed on a support mechanism of the feeding device and are input to the printer or business machine to be printed or processed.  
         [0005]     The conventional support mechanism usually includes multiple extension plates to support the media sheets. The extension plates provide sufficient support area for the media sheets. Nevertheless, extending or rotating a conventional support mechanism requires several steps and may be considered inconvenient.  
         [0006]     Hence, there is a need to provide an automatic support mechanism. The present automatic support mechanism can automatically extend or retract without requiring numerous complex steps, thus simplifying operation.  
       SUMMARY OF THE INVENTION  
       [0007]     Accordingly, an object of the invention is to provide an automatic support mechanism comprising a fixed base, a first supporting member, a second supporting member and an extendable supporting member. The first supporting member is rotatably connected to the fixed base. The second supporting member is rotatably connected to the fixed base and is slidably connected to the first supporting member. The extendable supporting member is movably disposed between the first supporting member and the second supporting member. The extendable supporting member automatically moves between a received position and an extended position by relative rotation and slide of the first and second supporting members.  
         [0008]     The automatic support mechanism further comprises a guiding member disposed on the second supporting member and having a guiding portion and a first toothed portion.  
         [0009]     The first supporting member further comprises a sliding portion and the second supporting member further comprises a sliding groove and a gear set. The guiding portion of the guiding member pivots to the sliding portion and slides in the sliding groove. The first toothed portion of the guiding member engages the gear set.  
         [0010]     The extendable supporting member further comprises a guiding groove and a second toothed portion formed therein. The gear set of the second supporting member is in the guiding groove and engages the second toothed portion. The extendable supporting member moves between the received position and the extended position by transmission of the guiding member and gear set.  
         [0011]     The gear set further comprises a first gear and a second gear coaxially connected thereto. The first toothed portion of the guiding member engages the first gear, and the second toothed portion of the guiding groove engages the second gear. The first and second gears are formed integrally.  
         [0012]     The teeth and diameter of the first gear are smaller than those of the second gear.  
         [0013]     The first toothed portion of the guiding member is a continuous toothed strip or rack.  
         [0014]     The second toothed portion of the guiding groove is a continuous toothed strip or rack.  
         [0015]     The first supporting member further comprises a first end and a second end and the second supporting member further comprises a third end and a fourth end. The first and third ends are connected to the fixed base. The sliding portion is formed on the second end, and the sliding groove is formed on the fourth end. The first end is separated from the third end by a predetermined distance.  
         [0016]     The received position is between the first supporting member and the second supporting member.  
         [0017]     The extended position is outside the first and second supporting members.  
         [0018]     An object of the invention is to provide an extension method of the automatic support mechanism. The extension method comprises the step of rotating the first and second supporting members in a first direction such that the first supporting member rotates relative to the second supporting member and slides thereon in a second direction, and the extendable supporting member moves to an extended position from a received position in a third direction.  
         [0019]     Another object of the invention is to provide a retraction method of the automatic support mechanism. The retraction method comprises the step of rotating the first and second supporting members in a fourth direction such that the first supporting member rotates relative to the second supporting member and slides thereon in a third direction, and the extendable supporting member moves to a received position from an extended position in a second direction.  
         [0020]     Yet another object of the invention is to provide an operation method of the automatic support mechanism. The operation method comprises the steps of rotating the first and second supporting members in a first direction such that the first supporting member rotates relative to the second supporting member and slides thereon in a second direction, and the extendable supporting member moves to an extended position from a received position in a third direction; and rotating the first and second supporting members in a fourth direction such that the first supporting member rotates relative to the second supporting member and slides thereon in the third direction, and the extendable supporting member moves to the received position from the extended position in the second direction.  
         [0021]     The rotating axle of the first supporting member is separated from that of the second supporting member by a predetermined distance.  
         [0022]     The second direction is opposite to the third direction.  
         [0023]     The first direction is opposite to the fourth direction.  
         [0024]     A detailed description is given in the following embodiments with reference to the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0025]     The present invention can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:  
         [0026]      FIG. 1  is a schematic side view showing the automatic support mechanism of the invention in a received position;  
         [0027]      FIG. 2  is a schematic side view showing the automatic support mechanism of the invention in an extended position;  
         [0028]      FIG. 3  is a partial enlarged view according to  FIG. 2 ;  
         [0029]      FIG. 4  is a schematic right side view according to  FIG. 1 ;  
         [0030]      FIG. 5  is a schematic cross section taken along A-A of  FIG. 4 ;  
         [0031]      FIG. 6  is a schematic right side view without the first supporting member according to  FIG. 1 ; and  
         [0032]      FIG. 7  is a schematic top view according to  FIG. 2 .  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0033]     Referring to  FIG. 1  and  FIG. 2 , the automatic support mechanism  100  is employed in a printer or business machine to support media sheets and comprises a fixed base  110 , a first supporting member  120 , a second supporting member  130 , a guiding member  140  and an extendable supporting member  150 .  
         [0034]     The first supporting member  120  is rotatably connected to the fixed base  110  and has a sliding portion  121 . Specifically, the first supporting member  120  has a first end  122  and a second end  123 . The first end  122  is rotatably connected to the fixed base  110 . The sliding portion  121  is formed on the second end  123 .  
         [0035]     Referring to  FIG. 5 , the second supporting member  130  is rotatably connected to the fixed base  110  and has a sliding groove  131  and a gear set  132  fixed thereon. Specifically, the second supporting member  130  has a third end  133  and a fourth end  134 . The third end  133  is rotatably connected to the fixed base  110 . The sliding groove  131  is formed on the fourth end  134 . Additionally, as shown in  FIG. 5 , the gear set  132  comprises a first gear  135  and a second gear  136  coaxially connected thereto. In this embodiment, the first gear  135  and second gear  136  are formed integrally. Specifically, the teeth and diameter of the first gear  135  are smaller than those of the second gear  136 , as shown in  FIG. 6 . When the gear set  132  rotates, the circumferential distance run by the first gear  135  is smaller than that by the second gear  136 .  
         [0036]     As shown in  FIG. 6 , the guiding member  140  is disposed on the second supporting member  130  and has a guiding portion  141  and a first toothed portion  142 . As shown in  FIG. 3 , the guiding portion  141  pivots to the sliding portion  121  of the first supporting member  120 . The guiding portion  141  and sliding portion  121  simultaneously slide in the sliding groove  131  of the second supporting member  130 . As shown in  FIG. 5  and  FIG. 6 , the first toothed portion  142  of the guiding member  140  is a continuous toothed strip or rack and engages the first gear  135  of the second supporting member  130 .  
         [0037]     As shown in  FIG. 6 , the extendable supporting member  150  is disposed on the guiding member  140  and under the first supporting member  120 . The extendable supporting member  150  comprises a guiding groove  151  and a second toothed portion  152  formed therein. Specifically, the second toothed portion  152  is formed on the inner wall of the guiding groove  151  and is a continuous toothed strip or rack. Additionally, the gear set  132  of the second supporting member  130  is in the guiding groove  151  of the extendable supporting member  150 , and the second toothed portion  152  of the guiding groove  151  engages the second gear  136  of the gear set  132 .  
         [0038]     Accordingly, the first supporting member  120  and second supporting member  130  are rotatably connected to the fixed base  110 . Namely, the first supporting member  120  is rotatably connected to the fixed base  110  by means of the first end  122  thereof while the second supporting member  130  is rotatably connected to the fixed base  110  by means of the third end  133  thereof. Specifically, the first end  122  is separated from the third end  133  by a predetermined distance.  
         [0039]     When the first supporting member  120  and second supporting member  130  rotate, the extendable supporting member  150  can move between a received position I and an extended position II by movement of the guiding member  140  and transmission of the gear set  132 . Specifically, the received position I is between the first supporting member  120  and the second supporting member  130  while the extended position II is outside the first supporting member  120  and second supporting member  130 .  
         [0040]     The following description is directed to the operation of the automatic support mechanism  100 .  
         [0041]     When the automatic support mechanism  100  extends, as shown in  FIG. 1  and  FIG. 2 , the first supporting member  120  is rotated in a first direction D 1  such that the sliding portion  121  of the first supporting member  120  and guiding portion  141  of the guiding member  140  slide in the sliding groove  131  of the second supporting member  130  in a second direction D 2 . At this point, the second supporting member  130  rotates in the first direction D 1  and the guiding member  140  slides in the second direction D 2 . As shown in  FIG. 6 , due to the first toothed portion  142  of the guiding member  140  engaging the first gear  135  of the second supporting member  130  and the guiding member  140  sliding in the second direction D 2 , the first gear  135  then rotates counterclockwise and thereby the second gear  136  rotates counterclockwise. As shown in  FIGS. 2, 5  and  6 , the second toothed portion  152  of the guiding groove  151  of the extendable supporting member  150  engages the second gear  136  and the axle  137  of the first gear  135  and second gear  136  is fixed on the second supporting member  130 . As shown in  FIG. 2  and  FIG. 7 , the second gear  136  rotating counterclockwise thus moves the second toothed portion  152  of the guiding groove  151  in a third direction D 3  until the extendable supporting member  150  moves outside the first supporting member  120  and second supporting member  130  in the third direction D 3 . At this point, the automatic extension of the automatic support mechanism  100  is complete.  
         [0042]     When the automatic support mechanism  100  retracts, as shown in  FIG. 1  and  FIG. 2 , the second supporting member  130  is rotated in a fourth direction D 4  such that the sliding portion  121  of the first supporting member  120  and guiding portion  141  of the guiding member  140  slide in the sliding groove  131  of the second supporting member  130  in the third direction D 3 . At this point, the first supporting member  120  rotates in the fourth direction D 4  and the guiding member  140  slides in the third direction D 3 . As shown in  FIG. 2  and  FIG. 7 , due to the first toothed portion  142  of the guiding member  140  engaging the first gear  135  of the second supporting member  130  and the guiding member  140  sliding in the third direction D 3 , the first gear  135  then rotates clockwise and thereby the second gear  136  rotates clockwise. Similarly, the second toothed portion  152  of the guiding groove  151  of the extendable supporting member  150  engages the second gear  136  and the axle  137  of the first gear  135  and second gear  136  is fixed on the second supporting member  130 . The second gear  136  rotating clockwise thus moves the second toothed portion  152  of the guiding groove  151  in a second direction D 2  until the extendable supporting member  150  moves to a position between the first supporting member  120  and the second supporting member  130  in the second direction D 2 . At this point, retraction of the automatic support mechanism  100  is complete.  
         [0043]     Accordingly, the second direction D 2  is opposite to the third direction D 3  and the first direction D 1  is opposite to the fourth direction D 4 .  
         [0044]     While the invention has been described by way of example and in terms of the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. To the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art). Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.