Patent Publication Number: US-8109714-B2

Title: Sewage pump

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a sewage pump, and more particularly to a sewage pump that additionally comprises an auxiliary blade set so that the sewage pump performs a two-step smashing function to improve durability of the sewage pump, the breaking efficiency and the sewage draining efficiency. 
     2. Description of Related Art 
     Conventional sewage pumps as shown in  FIGS. 1 and 2  each substantially has a central shaft  1  of a motor sleeved with a water paddle disk  2  and a wheel blade  3  that are driven to rotate by the driving of motor. The water paddle disk  2  has multiple paddle sheets arranged in whirl on its lower surface and is accommodated inside a paddle chamber  5  of a lower base  4 . The wheel blade  3  has multiple blade sheets in a certain number and is mounted in a precipitation inlet  6  below the paddle chamber  5 . Moreover, a gear ring  7  is attached on an inner wall of the precipitation inlet  6 . A precipitation outlet  8  is defined at one side of the paddle chamber  5  to connect to a universal joint with drain pipe (now shown). By having the above-described structure, the central shaft  1  drives the water paddle disk  2  and the wheel blade  3  to rotate and to cause current suction function to drain the precipitation via the precipitation inlet  6  below the paddle chamber  5  when the motor of sewage pump operates. Meanwhile, the wheel blade  3  cooperates with the gear ring  7  to smash and scatter the precipitation and then the paddle sheets on the water paddle disk  2  push the precipitation to the precipitation outlet  8  to drain out via the drain pipe. Therefore, the precipitation on a bottom of the sewage tank can be eliminated. 
     However, the conventional sewage pump can not perform sufficient smashing efficiency and some large precipitation pieces stick to the water paddle disk  2  because only one stage of smashing by the wheel blade cooperating with the gear ring is short in processing period and insufficient to completely smash the precipitation. Therefore, the large pieces of the precipitation get stuck to the paddle sheets of the water paddle disk  2 . Thus, the precipitation can not be drained out smoothly and the operation of the water paddle disk  2  is interrupted. In these cases, the smashing efficiency is reduced and malfunction rate is increased. 
     Additionally, still another conventional sewage pump as disclosed in U.S. Pat. No. 7,159,806 has a wheel blade mounted in the precipitation inlet on the lower base of the pump to smash and scatter the precipitation sucked into the sewage pump. Although the wheel blade operates upward and downward in reciprocation when smashing, the efficiency is still poor and the precipitation can not be smashed and eliminated completely. 
     SUMMARY OF THE INVENTION 
     A main objective of the present invention is to provide a sewage pump that performs a two-step smashing process before precipitation is conducted into a paddle chamber to ensure no coagulation of precipitation and to make the precipitation drain out easily to improve operational efficiency of the sewage pump. 
     Another main objective of the present invention is to provide a sewage pump that comprises an additional auxiliary blade set to achieve the two-step smashing process to efficiently eliminate problems of precipitation blocking to the paddle sheets on the water paddle disk so that the operational efficiency can be maintained and thus the malfunction possibility is reduced. 
     To overcome the foregoing main objectives of the sewage pump in the present invention, the sewage pump comprises: 
     a motor providing the power and having a central axle; 
     a lower base with a blade chamber attached to the motor and having an inlet and an outlet defined in the lower base to communicate with the blade chamber; 
     a water paddle disk received inside the blade chamber and mounted on the central axle; 
     a gear ring attached to the inlet and a first wheel blade accommodated inside the gear ring and mounted on the central axle; 
     an auxiliary blade set mounted between the water paddle disk and the first wheel blade and comprising:
         a stationary blade base with a through hole attached to the lower base over the inlet; and   a second wheel blade accommodated inside the through hole of the stationary blade base and mounted on the central axle, thereby, the second wheel blade is driven to rotate synchronously with the water paddle and the first wheel blade by the central axle of the motor.       

     By adding the auxiliary blade set, the two-step smashing function is achieved. 
     Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a partially cross-sectional side view of a conventional sewage pump in accordance with the prior art; 
         FIG. 2  is a partially cross-sectional side view of another conventional sewage pump in accordance with the prior art; 
         FIG. 3  is an exploded perspective view of two blade sets with a water paddle disk in a sewage pump in accordance with the present invention; and 
         FIG. 4  is an exploded perspective view of the blade sets with the water paddle disk of  FIG. 3 , wherein those elements are placed reversely; 
         FIG. 5  is a cross-sectional side view of the blade sets with the water paddle disk of  FIG. 3 , wherein those elements are assembled; 
         FIG. 6  is cross-sectional top view of the blade sets along line A-A as shown in  FIG. 5 ; 
         FIG. 7  is a cross-sectional view of a first wheel blade cooperating with a gear ring; 
         FIG. 8  is an operational view of the blade sets with the water paddle disk in the sewage pump with one drain pipe; and 
         FIG. 9  is an operational view of the blade sets with the water paddle disk in the sewage pump mounted with another drain pipe. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A sewage pump in accordance with the present invention is to mount an additional auxiliary blade set between a water paddle disk and a first wheel blade within the blade chamber, wherein the blade set comprises a stationary annular blade base and a second wheel blade. The stationary annular blade base is mounted on a diameter-enlarged recess in a lower base over an inlet of precipitation. The second wheel blade is rotatably received in the stationary annular blade base. Thereby, the water paddle disk, the first and second wheel blades are coaxially and synchronously driven by a motor shaft. Meanwhile, an upper edge of the stationary annular blade base and a side periphery of the second wheel blade respectively have blade sheets in certain predetermined numbers. When the sewage pump is driven by its motor, the water paddle disk, the first and second wheel blades are rotated to cause a suction force to drive precipitation at the bottom of the sewage pump flow into the blade chamber via the precipitation inlet. The first wheel blade cooperates with a gear ring to perform a first smashing stage and then the auxiliary blade set performs a second smashing stage to improve the smashing efficiency of the sewage pump. 
     With reference to  FIGS. 3 to 9 , the sewage pump of the present invention comprises a pump  10 , a lower base  20  with a blade chamber  21  mounted to a bottom of the pump  10 , a water paddle disk  30  and a first wheel blade  40  with a gear ring  41  received inside the blade chamber  21 , and an auxiliary blade set mounted between the water paddle disk  30  and the first wheel blade  40 . 
     The pump  10  has a motor  11  with a central axle  12  penetrating the water paddle disk  30 , the auxiliary blade set and the first wheel blade  40 . The pump  10  is mounted on the lower base  20  by screws. The lower base  20  is hollow to perform the blade chamber  21  and has a lower port with a precipitation inlet  22 . The gear ring  41  is attached to an inner periphery of the lower port and aligns with the first wheel blade  40  in horizontal. The first wheel blade  40  is coaxially mounted with the water paddle disk  30  and the auxiliary blade set by the central axle  12  so that the motor  11  is enabled to drive the water paddle disk  30  and the first wheel blade  40  synchronously. The first wheel blade  40  and the gear ring  41  respectively have multiple first blade sheets  42 ,  43  to perform a first smashing process to disintegrate the precipitation when the first wheel blade  40  rotates. Moreover, a precipitation outlet  23  is defined at a sidewall of the lower base  20  to communicate with the blade chamber  21  and mounted with a universal joint or a drain pipe (not numbered, as shown in  FIGS. 8 and 9 ). By having the arrangement described above, when the motor  11  of the pump  10  actuates, the water paddle disk  30  and the first wheel blade  40  are driven synchronously to generate a current suction force to draw the precipitation in sewage tank (now shown) into the blade chamber  21  via the precipitation inlet  22 . Meanwhile, the precipitation is smashed by the operation of the first wheel blade  40  with the gear ring  41  and then smashed precipitation is drained out via the precipitation outlet  23  and the drain pipe. Thereby, the precipitation in the sewage tank is eliminated. 
     To improve the smashing efficiency, the sewage pump further has the auxiliary blade set mounted between the water paddle disk  30  and the first wheel blade  40  inside the blade chamber  21  of the lower base  20 . The auxiliary blade set comprises a stationary annular blade base  50  and a second wheel blade  60 . The annular blade base  50  is mounted at the lower port of the lower base  20  that particularly has a diameter-enlarged recess  24  snugly engaged to the annular blade base  50  for securing. The annular blade base  50  has a circular body  51  and a through hole  52  defined at its center and multiple blade sheets  53  formed at its top face in certain predetermined numbers. Each blade sheet  53  has a slope face  54  with a sharp inner edge facing and around the through hole  52 . Moreover, multiple screws holes  55  are defined through the circular body  51  to make the stationary annular blade base  50  to be secured on the lower base  20  by screws  56 . Because the blade sheets  53  of the stationary annular blade base  50  are formed on the top face adjacent to the water paddle disk  30 , multiple paddle sheets  31  formed on a bottom face of the water paddle disk  30  in shape of vortex can not be located close to an axle hole  32  at the center but are spaced from the axle hole  32  with a distance that extends from the axle hole  32  to substantially close to an outer radius of the blade sheets  53  on the stationary annular blade base  50  (particularly shown in  FIG. 6 ). Thereby, the water paddle disk  30  is enabled to rotate freely without being interrupted by the blade sheet  53  of the stationary annular blade base  50 . The second wheel blade  60  is received within the through hole  52  of the stationary annular blade base  50 , has a threaded hole  61  defined at its center to engage to the central axle  12  of the motor  11 , and has multiple blade sheets  62  in certain predetermined numbers extending outward and vortically. As shown in  FIG. 5 , the blade sheets  62  of the second wheel blade  60  align the blade sheets  52  on the stationary annular blade base  50  and the paddle sheets  31  in horizontal and slightly contact with the blade sheets  53  of the stationary annular blade base  50  when the water paddle disk  30  and the auxiliary blade set are assembled within the blade chamber  21  of the lower base  20 . 
     By composing the foregoing described structure, the central axle  12  drives the water paddle disk  30 , the auxiliary blade set and the first wheel blade  40  coaxially mounted thereon to rotate synchronously to generate current suction efficiency and to draw precipitation at the bottom of the sewage tank into the lower base  20  via the precipitation inlet  22  when the motor  11  of the pump  10  actuates. The first wheel blade  40  and the gear ring  41  within the precipitation inlet  22  perform a first smashing process to the precipitation and then the second wheel blade  60  cooperating with the stationary annular blade base  50  perform a second smashing process to improve pulverizing efficiency to the precipitation without coagulation. Then smashed precipitation with the sewage is driven by rotation of the paddle sheets  31  on the water paddle disk  30  and drained out via the precipitation outlet  23  and the drain pipe to obtain high efficiency of eliminating the precipitation. 
     According to above illustration, the sewage pump having the fundamental smashing function performed by water paddle disk  30 , the gear ring  41  and the first wheel blade  40  further comprises a stationary annular blasé base  50  and a second wheel blade  60  additionally mounted between the water paddle disk  30  and the first wheel blade  40  to make the sewage pump have two-step smashing function. Wherein, the conventional first wheel blade  40  and the gear ring  41  within the precipitation inlet  22  perform the first smashing process and then the stationary blade base  50  and the second wheel blade  60  perform the second smashing process to ensure the precipitation fluffy and to reduce coagulation and stuck possibility before the precipitation is drained to the water paddle disk  30 . Thereby, the sewage pump is improved in operational efficiency and has less malfunction possibility and low repair cost. In summary, the sewage pump of the present invention has excellent industrial utility and practical value. 
     Although this invention has been described in its preferred form with a certain degree of particularity, it is understood that the present invention of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts any be resorted to without departing from the spirit and scope of the invention.