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BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a toilet flushing device, and more particularly to a dual-flush toilet device that is capable of controlling and saving water thereof with one toilet flushing handle and is commonly applicable to all kinds of toilet cisterns. 
         [0003]    2. Brief Description of the Related Art 
         [0004]      FIG. 1  illustrates the existing dual-flush toilet device, wherein a toilet flushing handle set  11  is disposed at lateral surface of a toilet cistern  10 . The toilet flushing handle set  11  comprises a first toilet flushing handle  111  and a second toilet flushing handle  112 , wherein the first toilet flushing handle  111  links up with a first connecting rod  113 . One end of the first connecting rod  113  is attached to an end of a first chain  133 , wherein the other end of the first chain  133  is attached to a lower valve body  122 . The lower valve body  122  is disposed on top of a flush valve  120  of an overflow tube  12  and the front side thereof is connected to an auxiliary float body  123 . The second toilet flushing handle  112  links up with a second connecting rod  114 , wherein one end of the second connecting rod  114  is attached to an end of a second chain  132 ; and the other end of the second chain  132  is attached to an upper valve body  121  that is disposed on top of the lower valve body  122 . The second chain  132  is further disposed of a small float ball  131 . When flushing stool, press the first toilet flushing handle  111  to lift the lower valve body  122  and discharge water; since the auxiliary float body  123  positioned in front of the lower valve body  122  has a large volume, the time required for the lower valve body  122  to cover up the flush valve  120  is longer and the discharged water amount is therefore larger. When flushing urine, press the second toilet flushing handle  112  to lift the upper valve body  121  and discharge water; since the small float ball  131  is of small volume, the time required for the upper valve body  121  to cover up the lower valve body  122  is shorter and therefore the discharged water amount is smaller. 
         [0005]    The foregoing prior arts of the dual-flush toilet device (hereinafter the prior arts) are of the following deficiencies:
   1. The first and second connecting rods  113  and  114  of different kinds of toilet cisterns are of different pressing angles, therefore the repair parts are not commonly applicable. When the original model&#39;s production stops, it has to be replaced by a repair part of different model or different brand, and the water discharge amount is hence inaccurate.   2. The first and second connecting rods  113  and  114  are capable of controlling the water discharge amount; however, the using of the small float ball  131  and the auxiliary float body  123  of the prior art to control water discharge amount is actually not accurate due to the swaying movement of the small float ball  131  and the auxiliary float body  123  caused by the water flow in the toilet cistern  10 .   
 
       SUMMARY OF THE INVENTION 
       [0008]    In order to overcome the deficiencies of the prior art, a primary object of the present invention is to provide a dual-flush toilet device that is capable of controlling and saving water thereof with one toilet flushing handle and is commonly applicable to all kinds of toilet cisterns. 
         [0009]    With the above object in mind, the dual-flush toilet device of the present invention comprises an outer casing, a gear set, a ring disk set, a connecting rod set and a drive set; wherein the drive set comprises a toilet flushing handle. By pressing or lifting the toilet flushing handle towards different directions, the discharged water amount can be controlled accurately and thereby achieves the goal of water saving. 
         [0010]    The outer casing is disposed of a ventilation set comprising an air cell disposed in a first casing body thereof, a control valve, a connecting base and an air duct. The drive set is comprised of a toilet flushing handle, a fixing axle cover, a drive rod, a cistern fixing nut and a fixing rotate screw. 
         [0011]    The connecting rod set is comprised of a connecting rod head having a connecting rod, and a stop seat. 
     
    
     
       BRIEF DESCRIPTION OF THE INVENTION 
         [0012]    The detail structure, the applied principle, the function and the effectiveness of the present invention can be more fully understood with reference to the following description and accompanying drawings, in which: 
           [0013]      FIG. 1  is a perspective view illustrating the prior art; 
           [0014]      FIG. 2  is an exploded perspective view according to the present invention; 
           [0015]      FIG. 3  is a perspective view of the first casing body according to the present invention; 
           [0016]      FIG. 4  is a perspective view of the second casing body according to the present invention; 
           [0017]      FIG. 5  illustrates an embodiment according to the present invention; 
           [0018]      FIG. 6  is a sectional view according to the present invention; 
           [0019]      FIG. 7  is a schematic representation of urine-flushing operation according to the present invention; 
           [0020]      FIG. 8  is a schematic representation of the gear set actuation according to the present invention; 
           [0021]      FIG. 9  is the first I-I sectional view according to the present invention; 
           [0022]      FIG. 10  is the second I-I sectional view according to the present invention; 
           [0023]      FIG. 11  is a schematic representation of stool-flushing operation according to the present invention; 
           [0024]      FIG. 12  is the first II-II sectional view according to the present invention; and 
           [0025]      FIG. 13  is the second II-II sectional view according to the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0026]    The above and further objects and novel features of the invention will more fully appear from the following detailed description when the same is read in connection with the accompanying drawing. It is to be expressly understood, however, that the drawing is for purpose of illustration only and is not intended as a definition of the limits of the invention. 
         [0027]    With reference to  FIGS. 2 and 5 , wherein the toilet flushing device A of the present invention comprises an outer casing  2 , a gear set  3 , a ring disk set  4 , a connecting rod set  5  and a drive set  6 . 
         [0028]    Please refer to  FIGS. 3 and 4 , wherein the outer casing  2  is comprised of a first casing body  21  and a second casing body  22 . The first casing body  21  has a receiving space  210 , and a plurality of fixing studs  212  is disposed therein. A first axle hole  211  penetrates the center of the first casing body  21 . The second casing body  22  is disposed of a second axle hole  221  and a plurality of fixing hole columns  224  at the inner surface thereof. At least one arc-shaped retaining wall  223  is disposed to surround peripheral edge of the second axle hole  221 , and the fixing hole columns  224  correspondingly fit with the fixing studs  212  to allow a bolt C to screw lock thereon. One of the lateral surface  225  of the second casing body  22  is disposed of a notch  222 . 
         [0029]    The gear set  3  comprises:
       a drive seat  31  having a seat body  312  and a first gear  311  disposed at the bottom thereof, wherein at least one third convex rib  313  is disposed at peripheral edge of the seat body  312 , and a housing aperture  314  penetrates through center of the seat body  312 ;   a driven seat  32  having a seat body  322 , wherein a second gear disposed at the bottom of the seat body  322  and a third axle hole  323  that is polygonal is disposed at the center of the seat body  322 ;   a third gear  33  meshing with the second gear  32 ;   a fourth gear  34  meshing with the third gear  33 ; and   a fifth gear  35  coaxially linking up with the fourth gear  34  and meshing with the first gear  311  of the drive seat  31 .       
 
         [0035]    The ring disk set  4  comprising:
       a ring disk body  41  having a rounded hole  410 , wherein a plurality of supporting pieces  412  are disposed along the periphery edge of the ring disk body  41  and an arc-shaped groove  415  is disposed at the bottom lateral surface of the ring disk body  41 , with an air hole  416  disposed thereon, as illustrated in  FIG. 9 ; further, an arc-shaped chamber  411  and a stop block  414  are provided at the top surface of the ring disk body  41 , wherein a fixing column  413  is convexly disposed at one side of the arc-shaped chamber  411 ;   a spring  42  fitting with the fixing column  413 ; and   an arc-shaped pushing seat  43  disposed inside the arc-shaped chamber  411  and being pushed by the spring  42 .       
 
         [0039]    The connecting rod set  5  comprising:
       a connecting rod head  51  comprising a connecting rod  514  extends from the periphery edge of a rounded main body  511 , wherein a plurality of hanging holes  515  is disposed at the connecting rod  514  to allow hanging of a chain  516  as illustrated in  FIG. 5 ; the rounded main body  511  further comprises a fourth axle hole  512  and a notch  513 , wherein at least one first convex rib  517  is disposed on the inner wall of the fourth axle hole  512 ;   a stop seat  52  having a polygon hole  521 , wherein a stop piece  522  and at least one second convex rib  523  are disposed along the periphery edge of the stop seat  52 .       
 
         [0042]    The drive set  6  comprising:
       a toilet flushing handle  61  having a handle body  611 , wherein a rod body  612  extends from one side of the handle body  611 , and a first joining section  615 , a second joining section  613  and an external thread section  614  is disposed on the rod body  612 ;   a fixing axle cover  62  having an axle hole  621  penetrating the center thereof to allow insertion of the rod body  612 , and peripheral edge of the fixing axle cover  62  provides an external thread section  622 ;   a cistern fixing nut  63  screw locked to the external thread section  622  of the fixing axle cover  62 ; and   a fixing rotate screw  64  having an inner thread hole  641  to allow screw locking with the external thread section  614  of the rod body  612 .       
 
         [0047]    The outer casing  2  of the toilet flushing device A further comprises a ventilation set  7  as illustrated in  FIGS. 2 ,  3  and  5 . The ventilation set  7  comprises:
       an air cell  214  disposed in the first casing body  21 , wherein the air cell  214  has a valve hole  213  to receive a control valve  71 , and is further disposed of a first through hole  215  and a second through hole  216  that are in connection to the valve hole  213 ;   the control valve  71  having a control handle  711  extending from the upper end thereof;   a connecting base  72  having a hollow through hole  721 , wherein one end of the connecting base  72  fits with the second through hole  216  and the other end of the connecting base  72  fits with an end of an air duct  73 ; and   the air duct  73 , wherein the other end thereof is connected to an air connector  931  of a valve body  93  that covers a flush valve  92  as illustrated in  FIG. 5 .       
 
         [0052]    Referring to  FIGS. 2 ,  5  and  6 , the toilet flushing device A assembled by the foregoing assemblies can be installed to a toilet cistern  90  at a pivot hole  90  thereon; hang one end of the chain  516  on the hanging hole  515  of the connecting rod  514 , and the other end of the chain  516  on a hanging part  932  of a valve body  93 . One side of the valve body  93  suspends on a suspension part  911  of an overflow tube  91 , and the valve body  93  covers a water outlet  94  of the flush valve  92 . 
         [0053]    With reference to  FIGS. 7 ,  8 ,  9  and  10 ; when flushing urine, the user should lift the toilet flushing handle  61 . As the toilet flushing handle  61  is lifted upwards, the rod body  612  links up with the driven seat  32 , the second gear  321  of the driven seat  32  meshes with and actuates the third gear  33 , the third gear  33  meshes with and actuates the fourth gear  34 , the fourth gear  34  rotates and coaxially actuates the fifth gear  35 , and the fifth gear  35  meshes with and actuates the first gear  311 . By the foregoing method a decelerate effect is achieved and the third convex rib  313  fits with the first convex rib  517  in order to allow the rotation of the connecting rod head  51 , thereby control the speed of the connecting rod  514  lifting the valve body  93  to prevent it from moving too fast, and hence the discharged water amount can be smaller. 
         [0054]    With reference to  FIGS. 11 ,  12  and  13 ; when flushing stool, the user should press the toilet flushing handle  61 . As the toilet flushing handle  61  is pressed downwards, the rod body  612  of the toilet flushing handle  61  links up with the stop seat  52  and drives it to rotate, the second convex rib  523  of the stop seat  52  fits with the first convex rib  517  to rotate the connecting rod head  51  in order to allow the connecting rod  514  to lift the valve body  93 . Since there is no buffer therebetween, the discharged water amount is larger. Further, during the handle-pressing process, the stop piece  522  pushes the arc-shaped pushing seat  43  to drive it to slide along the arc-shaped chamber  411  of the ring disk body  41 ; by the buffer of the spring  42 , the lifting angle of the connecting rod  514  is bigger and thereby extends the water discharging time. 
         [0055]    The ventilation set  7  of the toilet flushing device A adjusts the speed of the valve body  93  covering the flush valve  92 ; it controls the discharged water amount by controlling the amount of air flowing in and out. The covering is faster when the air amount is larger, and the discharged water amount is therefore smaller; and the covering is slower when the air amount is smaller, and the discharged water amount is therefore larger. On the contrary, as the air throughput amount is smaller or without any airflow, the covering time of the valve body  93  is longer since the covering relies on only the water, and the discharged water amount is therefore larger. 
         [0056]    While the invention has been described with reference to a preferred embodiment thereof, it is to be understood that modifications or variations may be easily made without departing from the spirit of this invention, which is defined in the appended claims.

Summary:
The present invention relates to a toilet flushing device including an outer casing, a gear set, a ring disk set, a connecting rod set and a drive set; wherein the drive set includes a toilet flushing handle. By pressing or lifting the toilet flushing handle towards different directions, the discharged water amount can be controlled accurately and thereby achieves the goal of water saving.