Abstract:
A device for generating a jet stream of air entrained water for cleaning teeth and gums, includes two pumps disposed to respectively and sequentially pump in and out of internal ports thereof from first water and air transit chambers, water flow and air stream to generate raised water and air pressures. Two valves are disposed respectively to be moved by the water and air pressures to block or permit entry of the water flow and the air stream into second water and air transit chambers. A mixing outlet is disposed downstream of and to merge water and air outlet ports of the second water and air transit chambers to obtain an accelerated stream of the air entrained water for cleaning teeth and gums.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    This invention relates to a device for cleaning teeth and gums, more particularly to a device for generating a jet stream of air entrained water adapted for cleaning teeth and gums.  
           [0003]    2. Description of the Related Art  
           [0004]    A conventional method for intruding air into water flow in a teeth cleaning apparatus is accelerating the water flow speed so as to generating a jet stream of air entrained water to result in an improved a cleaning effect. However, the increased water pressure, which arises as a result of acceleration of the water flow, will impact the teeth and gums of the user and results in uncomfortable feeling for the user.  
         SUMMARY OF THE INVENTION  
         [0005]    The object of the present invention is to provide a device which can generate a smooth and steady jet stream of air entrained water for cleaning teeth and gums of a user with minimal user discomfort.  
           [0006]    According to this invention, the device includes a water inlet for receiving a water flow from a reservoir, an air inlet admitting entrance of air stream, and a water and air mixing body which defines first water and air transit chambers spaced apart from each other, and second water and air transit chambers spaced apart from each other. The first water and air transit chambers respectively have first water and air inlet ports which are communicated respectively with the water inlet and the air inlet, and first water and air outlet ports which are disposed respectively downstream of the first water and air inlet ports. The second water and air transit chambers respectively have second water and air inlet ports which are communicated respectively with the first water and air outlet ports, and second water and air outlet ports which are disposed respectively downstream of the second water and air inlet ports. First and second pumps respectively have first and second internal ports which are communicated respectively with the first water and air transit chambers, and which are disposed respectively downstream of the first water and air inlet ports and upstream of the first water and air outlet ports. The first and second pumps can sequentially pump in and out of the first and second internal ports respectively, the water flow and the air stream respectively, thereby accelerating the speeds of the water flow and the air stream respectively so as to generate raised water and air pressures, respectively.  
           [0007]    First and second valves are disposed respectively between the first water inlet port and the first internal port, and between the first air inlet port and the second internal port. Each of the first and second valves is movable between a first closed position, where a respective one of the water flow and the air stream, being pumped out of a respective one of the first and second internal ports, is blocked from passing through a respective one of the first water and air inlet ports, while proceeding further to flow through a respective one of the first water and air outlet ports, and a first open position, where the respective one of the water flow and the air stream is pumped in a respective one of the first water and air transit chambers as well as the respective one of the first and second internal ports through the respective one of the first water and air inlet ports.  
           [0008]    Third and fourth valves are disposed respectively between the second water inlet port and the second water outlet port, and between the second air inlet port and the second air outlet port. Each of the third and fourth valves is moved by the respective one of the raised water and air pressures from a second closed position, where the respective one of the water flow and the air stream, which is being pumped in the respective one of the first water and air transit chambers when the respective one of the first and second valves is in the first open position, is blocked from entering into a respective one of the second water and air outlet ports, to a second open position, where the respective one of the water flow and the air stream, which is flowing through the respective one of the first water and air outlet ports when the respective one of the first and second valves is in the first closed position, further proceeds to the respective one of the second water and air outlet ports through a respective one of the second water and air transit chambers. A mixing outlet is disposed downstream of and is disposed to merge the second water and air outlet ports so as to obtain an accelerated stream of the air entrained water.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]    Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiment of the invention, with reference to the accompanying drawings, in which:  
         [0010]    [0010]FIG. 1 is a perspective view of a preferred embodiment of a device according to this invention;  
         [0011]    [0011]FIG. 2 is an exploded perspective view showing a water and air mixing mechanism of the preferred embodiment;  
         [0012]    [0012]FIG. 3 is a sectional view showing the water and air mixing mechanism and a driving mechanism of the preferred embodiment;  
         [0013]    [0013]FIG. 4 is a front view showing a portion of the water and air mixing mechanism;  
         [0014]    [0014]FIGS. 5 and 6 are partly cross-sectional views of the water and air mixing mechanism shown in FIG. 4, taken along lines I-I and II-II thereof, respectively; and  
         [0015]    [0015]FIG. 7 is an exploded perspective view of an ion-generating member of the preferred embodiment. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0016]    Referring to FIGS.  1  to  3 , the preferred embodiment of the device according to the present invention is shown to comprise a water and air mixing mechanism  1 , a driving mechanism  2 , and a mouthpiece  3 .  
         [0017]    The water and air mixing mechanism  1  includes front and rear mixing housings  12 ,  11  coupled to each other in an axial direction at two coupling walls  120 ,  110  thereof to form a water and air mixing body. On a front side  121  of the front mixing housing  12 , a water inlet  141  is disposed to be connected to a tube  144  so as to receive a water flow from an outlet  145  of a reservoir, and an air inlet  142  is disposed to admit entrance of air stream.  
         [0018]    With reference to FIGS. 4 and 5, the water and air mixing body defines first water and air transit chambers spaced apart from each other, and second water and air transit chambers spaced apart from each other. The first and second water transit chambers respectively have first water and air inlet ports  131 ,  132  which are formed in the coupling wall  120  and which are communicated respectively with the water inlet  141  and the air inlet  142  via channels  1411 ,  1421 . In the coupling wall  120 , two forwardly concaved portions  151 ,  154  are formed to surround respectively the first water and air inlet ports  131 ,  132 , and two forwardly concaved portions  152 ,  153  are formed inboard to the concaved portions  151 ,  154 . In addition, four through bores  161 ,  166 ,  163 ,  164  are formed in the concaved portions  151 ,  154 ,  152 ,  153 , respectively. As shown in FIG. 5, first water and air outlet ports  171 ,  172  are disposed to communicate with the through bores  161 ,  166 , and extend through the concaved portions  152 ,  153 , respectively. As such, the water flow and the air stream from the water and air inlets  141 ,  142  pass respectively and sequentially through the first water and air inlet ports  131 ,  132 , the concaved portions  151 ,  154 , the through bores  161 ,  166  and the first water and air outlet ports  171 ,  172  which define the first water and air transit chambers.  
         [0019]    The second water and air transit chambers respectively have second water and air inlet ports  162 ,  165  which are communicated respectively with the first water and air outlet ports  171 ,  172  and which are disposed respectively adjacent to the through bores  163 ,  164 . Referring to FIGS. 4 and 6, the through bores  163 ,  164  are formed respectively as second water and air outlet ports, and are communicated with a mixing port  133  via a channel  173 . A mixing tube  143  is disposed on a bottom wall  122  of the mixing housing  12 , and has a mixing outlet  1431  which is communicated with the mixing port  133  and which is connected to a flexible tube  146  for connection to the mouthpiece  3  (the construction thereof will be described below), as shown in FIG. 1. As such, the water flow and the air stream from the first water and air transit chambers can pass respectively and sequentially through the second water and air inlet ports  162 ,  165 , the concaved portions  152 ,  153 , the through bores  163 ,  164 , the channel  173 , and are mixed in the mixing port  133  to generate air entrained water. The air entrained water flows sequentially into the mixing outlet  1431  and the flexible tube  146  so as to further spray out from the mouthpiece  3 . Preferably, referring to FIGS. 4 and 5, the through bore  161  and the second water inlet port  162  are flush with each other so as to facilitate forming of the first water outlet port  171  in a manner that the mixing housing  12  is drilled from a side thereof, and that a plug  1711  is used to close one end of the drilled hole. The first air outlet port  172  and the channel  173  are formed in the same manner, and are provided with plugs  1721 ,  1731  to close one end of drilled holes thereof.  
         [0020]    Moreover, referring again to FIG. 2, the coupling wall  110  of the rear mixing housing  11  is formed with four receiving through bores  181 ,  182 ,  183 ,  184  that correspond with the concaved portions  151 ,  152 ,  153 ,  154 , respectively. The coupling wall  120  of the front mixing housing  12  is formed with four annular grooves  155  surrounding the concaved portions  151 ,  152 ,  153 ,  154  such that four rubber O-ring seals  156  are received respectively therein.  
         [0021]    Referring again to FIG. 3, first and second pumps  191 ,  194  respectively have first and second internal ports  1915 ,  1945  which are communicated respectively with the first water and air transit chambers in the axial direction via the receiving through bores  181 ,  184  formed in the coupling wall  110  of the rear mixing housing  11  so as to be disposed respectively downstream of the first water and air inlet ports  131 ,  132  and upstream of the first water and air outlet ports  171 ,  172 . Each of the first and second pumps  191 ,  194  includes a cylinder  1911 ,  1941  which is disposed in the rear mixing housing  11  and downstream of a respective one of the first and second internal ports  1915 ,  1945 , a piston  1912 ,  1942  which is disposed in the cylinder  1911 ,  1941  and which is movable reciprocally to sequentially pump in and out of a respective one of the first and second internal ports  1915 ,  1945 , the respective one of the water flow and the air stream, thereby accelerating the speeds of the water flow and the air stream so as to generate raised water and air pressures.  
         [0022]    Referring to FIGS. 2 and 3, first and second valves  1921 ,  1951  are disposed respectively between the first water inlet port  131  and the first internal port  1915 , and between the first air inlet port  132  and the second internal port  1945 . The first valve  1921  includes a valve portion which is disposed to be movable between first closed and open positions to respectively engage and disengage a valve seat portion of the first water inlet port  131 , and a guiding rod which extends from the valve portion away from the valve seat portion and which is insertable into an inner annular wall of the receiving through bore  181  so as to guide movement of the valve portion. The second valve  1951  is a valve plate which is partially connected to the corresponding O-ring seal  156 . Thus, when each of the first and second valves  1921 ,  1951  is in the first closed position, a respective one of the water flow and the air stream, which is pumped out of a respective one of the first and second internal ports  1915 ,  1945 , is blocked from passing back through a respective one of the first water and air inlet ports  131 ,  132 , while proceeding further to flow through a respective one of the first water and air outlet ports  171 ,  172 . When each of the first and second valves  1921 ,  1951  is in the first open position, the respective one of the water flow and the air stream is pumped in a respective one of the first water and air transit chambers as well as the respective one of the first and second internal ports  1915 ,  1945  through the respective one of the first water and air inlet ports  131 ,  132 .  
         [0023]    First and second biasing members  1922 ,  1952  are coiled springs, each of which is disposed between the respective valve  1921 ,  1951  and the respective receiving through bore  181 ,  184  to move the valve  1921 ,  1951  towards the first closed position.  
         [0024]    Third and fourth valves  1931 ,  1961  are valve plates which are partially connected to the corresponding O-ring seal  156 . Each of the third and fourth valves  1931 ,  1961  is moved by the respective one of the raised water and air pressures. Particularly, when a respective one of the first and second valves  1921 ,  1951  is in the first open position, a respective one of the third and fourth valves  1931 ,  1961  is in a second closed position, where the respective one of the water flow and the air stream, which has been pumped in the respective one of the first water and air transit chambers, is blocked from entering into a respective one of the second water and air outlet ports  163 ,  164 . Once the respective one of the first and second valves  1921 ,  1951  is in the first closed position, the respective one of the third and fourth valves  1931 ,  1961  will be in a second open position, where the respective one of the water flow and the air stream, which is flowing through the respective one of the first water and air outlet ports  171 ,  172 , further proceeds to the respective one of the second water and air outlet ports  163 ,  164  through a respective one of the second water and air transit chambers.  
         [0025]    Third and fourth biasing members  1932 ,  1962  are coiled springs which are disposed between the respective valve  1931 ,  1961  and the respective receiving through bore  182 ,  183  to bias the valves  1931 ,  1961  to move towards the second closed position against the forces of the raised water and air pressure.  
         [0026]    Referring to FIGS. 1 and 3, the driving mechanism  2  includes a motor with an output shaft  21  extending upwardly through a lower plate  1122  of a rear end  112  of the rear mixing housing  11 , a driving gear  22  rotated by the output shaft  21 , two transmission wheels  25 ,  26  disposed between an upper plate  1121  of the rear end  112  and the lower plate  1122  to mesh with and to be driven by the driving gear  22  to rotate in opposite directions, and two piston rods  27 ,  28 , each disposed to link the respective transmission wheel  25 ,  26  and the piston  1912 ,  1942  so as to transmit rotational force of the transmission wheel  25 ,  26  to the piston  1912 ,  1942 , thereby moving the piston  1912 ,  1942  reciprocally in the corresponding cylinder  1911 ,  1941 . Furthermore, an electric wire  23  of the motor can be wound by a wire winding member  24  in a known manner.  
         [0027]    The mouthpiece  3  includes a handle  31  communicated with the flexible tube  146 , a nozzle  32  with a plurality of spray holes  321 , and a control valve  311  to control the amount of water sprayed from the spray holes  321 . The flexible tube  146  can be wound by a tube winding member  33 .  
         [0028]    With such a construction, the first and second pumps  191 ,  194  are driven by the driving mechanism  2  to pump the water flow when pumping the air stream out, and to pump the water flow out when pumping the air stream in. Therefore, the water flow and the air stream with constant amounts can flow alternately into the mixing outlet  1431 , thereby resulting in a good cleaning effect and a comfortable feeling for the user.  
         [0029]    Preferably, referring to FIGS. 1 and 7, an ion-generating member  4  is disposed to communicate with and upstream of a connecting head  145  of the tube  144 , and includes porous positive, negative, and intermediate plates  41 ,  42 ,  43  to convert water of the water flow into ion-enriched water in a known manner so as to enhance the teeth cleaning effect. A cap  5  covers the connecting head  145  and communicates with the reservoir.  
         [0030]    While the present invention has been described in connection with what is considered the most practical and preferred embodiment, it is understood that this invention is not limited to the disclosed embodiment but is intended to cover various arrangements included within the spirit and scope of the broadest interpretations and equivalent arrangements.