A flushing device has two water outlets, wherein one outlet is connected to an arch of a trap of the toilet bowl. This outlet is connected to means with which a portion of the flushing water present in a flushing tank can be pressurized and released to this outlet. The water is briefly set into motion with the pressurized flushing water, and more effective emptying of the trap is achieved. The flushing device according to the present invention represents a lower load for the water pipes and operates with less noise than flushing valve-type devices.

CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application is a continuation-in-part of U.S. patent application Ser. No. 08/411,723, filed Mar. 29, 1995, and herein abandoned.  
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    1. Field of the Invention  
           [0003]    This invention relates to the field of plumbing devices, and in particular to a toilet tank that provides a pressurized stream of water to facilitate the removal of materials in the bowl.  
           [0004]    2. Description of Related Art  
           [0005]    A flushing device for a toilet that uses a reduced amount of water is known from EP-A-0 352 712. Two water feeds to a toilet bowl are provided in this flushing device. One water feed leads to the edge of the bowl, and the other feed leads to a trap arranged in the lower area of the bowl. During flushing, the bowl is cleaned with one flow of flushing water, and the water present in the trap is set into motion with the other flow of flushing water. The minimum amount of water necessary for an effective flushing is substantially smaller in such a flushing device than in a flushing device with only one flushing flow for cleaning the toilet bowl. In the design shown in FIG. 1 of the referenced patent, the flushing device is designed as a so-called flushing valve. To control the two flows of flushing water, a relatively complicated control device is necessary here. In addition, it is disadvantageous in this design that disturbing noises are generated during flushing despite the relatively small amount of flushing water. In addition, flushing valves are not approved in certain countries. FIG. 7 of the referenced patent shows a design in which the water used for one flushing is stored in a flushing water tank. A branch pipe, which leads to the trap of the toilet bowl, is connected to a discharge pipe of the flushing water tank. A complicated control device is necessary in this design as well, and valves and pressure indicator means, with which the two flows of flushing water are controlled, are necessary in the pipes.  
           [0006]    Similar flushing devices are shown in EP-A-0 369 377 and EP-A-0 415 432. Complicated control and regulating units are necessary in these designs as well.  
         BRIEF SUMMARY OF THE INVENTION  
         [0007]    It is an object of this invention to provide a flushing device of the class described above, which represents a substantially lower load for the water pipes than flushing valve-type devices. It is a further object of this invention to provide a flushing device that operates with less noise. It is a further object of this invention to achieve the necessary flushing effect with a minimal amount of flushing water.  
           [0008]    These objects and others are achieved by providing a flushing device wherein a portion of the flushing water present in the flushing water tank is pressurized during the flushing process. This pressurized water is released to the outlet, which leads to the trap arranged in the lower area of the toilet bowl. It is therefore possible with the flushing device according to the present invention to accelerate the water in the trap such that this trap will be flushed better. The water of the trap is briefly set into motion, and more effective emptying of the trap is achieved. Only the toilet bowl must then be cleaned and the partially emptied trap must be refilled with the flushing flow which is subject to gravity. Thus, an amount of pressureless flushing water and an amount of pressurized flushing water are released during one flushing in the flushing device according to the present invention. Thus, a smaller amount of flushing water is needed at equal flushing effect than with a common flushing tank. Compared with flushing valve-type devices, the flushing device according to the present invention represents a substantially lower load for the water pipes, and it corresponds to a common flushing tank in this respect.  
           [0009]    According to a variant of the present invention, the means with which an amount of flushing water can be pressurized has a piston-and-cylinder unit with a piston, to which water of the water supply pipe can be admitted during flushing. The piston is displaced by the pressure of the water from the supply pipe, and a defined amount of flushing water present in the unit is pressurized. Such a piston-and-cylinder unit may be accommodated in a flushing tank. Such a flushing tank can then be operated with a pushbutton.  
           [0010]    Especially effective flushing is achieved if the water present in the piston-and-cylinder unit is released with a delay under pressure by means of a control device. It can be achieved as a result that the flushing flow which is subject to gravity and the pressurized flushing flow will act essentially simultaneously in the siphon or trap. This control device nay be designed simply as a float, which actuates a servo-controlled intake valve.  
           [0011]    The present invention also pertains to a toilet unit wherein the nozzle is arranged inclined in relation to the horizontal such that the flushing water released through the nozzle exerts a movement directed downstream to the water present in the arch of the trap.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]    The invention is explained in further detail, and by way of example, with reference to the accompanying drawings wherein:  
         [0013]    [0013]FIG. 1 schematically shows a section through a toilet unit according to the present invention,  
         [0014]    [0014]FIG. 2 shows a vertical section through a flushing device according to the present invention,  
         [0015]    [0015]FIG. 3 shows a partially cutaway top view of the flushing device according to FIG. 2,  
     
    
       [0016]    Throughout the drawings, the same reference numerals indicate similar or corresponding features or functions.  
       DETAILED DESCRIPTION OF THE INVENTION  
       [0017]    [0017]FIG. 1 shows a flushing device  1 , which is connected to a toilet bowl  45  via a pipe elbow  12 . A drain valve  13 , which can be actuated with an actuating means  17  to release an opening  14  in the bottom of the tank  8 , is accommodated in a tank  8  of the flushing device  1 . The actuating means  17  may be a button or a pushbutton or another tripping means. The tank  8  also accommodates an intake valve  4 , which is connected to a water supply pipe  2 . With the intake valve  4  open, the tank  8  is filled with flushing water  50  to a predetermined level. When the drain valve  13  is opened, part of the flushing water  50  flows through the pipe elbow  12  and into a channel  51  of an edge  47  and flows in the direction of the arrows  53  along the inside of a bowl  56  in the downward direction into a U-shaped arch  46 , which forms a trap against a soil pipe  52 . Another, substantially smaller part of the flushing water  50  is pressurized with means in the tank  8 , which are described farther below, and it enters, via a pipe  9 , a nozzle  11 , which has a passage  57  into the interior of the arch  46 . This nozzle  11  is directed such that, as is shown in FIG. 1, water flowing in through the nozzle  11  flows in the direction of the arrow  58  into the water  70  present in the arch  46 . The direction of the arrow  58  is also the direction of flow of the water  70  during the flushing process and consequently during the emptying of the trap. A suitable slope angle α can be seen in FIG. 1. This angle α is, e.g., approx. 10 degrees and is preferably smaller than 45 degrees.  
         [0018]    The flushing flow entering through the nozzle  11  has excess pressure, while the flushing water entering the bowl  56  through the channel  51  is only under the action of the force of gravity. The amount of flushing water flowing in through the nozzle  11  during one flushing is preferably substantially smaller than the amount of flushing water released through the channel  51 . The flushing water entering the bowl under excess pressure in the direction of the arrow  58  moves the water  70  in the direction of the arrow  58  and causes the arch  46  to be better cleaned. The excrements present in the arch  46  are carried away and delivered to the soil pipe  52 . Flushing water that is under the action of the force of gravity enters the bowl  56  essentially simultaneously with the cleaning of the arch  46 , and it cleans the bowl. The flushing water, subject to gravity and flowing downward into the arch  46  intensifies the movement of the water  70  in the direction of the arrow  58  and refills the arch  46  with water. Thus, the two flushing flows cooperate and accelerate the water  70  in order to thus remove excrements from the arch  46 .  
         [0019]    [0019]FIGS. 2 and 3 show a preferred embodiment of the flushing device  1 . The tank  8  is equipped in the usual manner with a discharge pipe connection  59  arranged in the bottom and with a lid, not shown here. The pipe elbow  12  joins the tank  8  at the pipe connection  59 . The drain valve  13  may be a prior-art float valve, in which a valve pipe  16  is guided in a float housing  60 . The valve pipe  16  can be raised by a ring  19  with a pushbutton  17  pivotable around a support  18 . A valve disk  15  now releases the opening  14 , after which flushing water  50  present in the tank  8  flows through the pipe elbow  12  and into the channel  51 . The drain valve  13  automatically closes after the flushing process in the known manner.  
         [0020]    In addition, a piston-and-cylinder unit  6 , which consists essentially of two housing parts  33  and  40  and a double piston  61 , is also arranged in the tank  8 . The unit  6  is connected to the intake valve  4 , which is connected at a connection pipe  62  to the water supply pipe  2 .  
         [0021]    The intake valve  4  is a servo-controlled diaphragm valve. This closes an opening  28  in a passage  29  with a diaphragm  27  in the state shown in FIG. 2. A passage opening  63  in the diaphragm  27  connects a chamber  29   a  of the pipe connection  62  to a chamber  26  of a frame  23 . Water, which communicates with the water of the supply pipe  2  through the opening  63  and is under the same pressure, is present in the chamber  26 . Since the diaphragm  27  has a larger area against the chamber  26  than against the chamber  29   a , the latter is pressed upward against the valve seat of the opening  28 . The chamber  26  has a passage  25 , which is closed by a valve rod  24  mounted displaceably on the frame  23  in the arrangement shown. A float  21 , which is located in a float housing  20 , is arranged at the lower end of the valve rod  24 . With the flushing tank filled, the float is extensively below the water level marked by the letter A. A valve  22 , which is open when the flushing tank is filled and thus connects the interior of the float housing  20  to its outside, is arranged in the bottom of the float housing  20 . The housing  20  is filled with water and imparts buoyancy to the float  21 , which presses the rod  24  against a valve seat of the passage opening  25 .  
         [0022]    When the valve pipe  16  is lifted with the pushbutton  17  during a flushing, the water level in the tank  8  drops, and so does the water level in the float vessel  20  at the same time. Thus, the buoyancy of the float  21  thus continuously decreases, until it eventually drops down under its own weight, thus releasing the passage opening  25 . Water can escape from the chamber  26  to the outside through the passage  25 , as a result of which the pressure in the chamber  26  is immediately reduced. Due to the fact that the water pressure in the chamber  29   a  is now higher, the diaphragm  27  is moved downward and is lifted off from the opening  28 . The passage from the chamber  29   a  to the chamber  29   b  is thus open. Water can now enter the chamber  5 , which is sealed against an interior space  64  of the housing part  33  with a piston  30  and a circumferential lip seal  31 , from the supply pipe  2  through the passage  29 . The amount of water entering the chamber  5  per unit of time is limited by a flow governor  3  arranged in front of the diaphragm  27 . The flow governor  3  is preferably set such that the water flowing into the chamber  5  has a maximum flow pressure.  
         [0023]    The piston  30  is connected via a web  32  to a piston  37  arranged farther below it. This piston  37  has a nonreturn valve  36 , which is open in the position shown and connects the interior space  64  to an interior space  65  of the housing part  40 . With the valve  36  closed, the piston  37  seals the interior space  65  against the space  64  with a circumferential lip seal  38 . Thus, the two pistons  30  and  37  form a double piston  61 . The space  65  leads via a passage  41  to a nonreturn valve  7 , which has a closing body  42 , which can be lifted off from a valve seat  66  against the reactive force of a compression spring  43 . The nonreturn valve  7  has a connection pipe  44 , to which the pipe  9  leading to the nozzle  11  is connected.  
         [0024]    When pressurized water flows into the chamber  5  through the opened intake valve  4 , the piston  61  is moved downward by the pressure of this water against the reactive force of a compression spring  39 . The space  65  is filled with water, which is pressurized by the downwardly moving piston  37  and closes the nonreturn valve  36 . The water pressure in the space  65  continuously increases with the piston  37  moving downward, until the nonreturn valve  7  is opened at a defined pressure and water can flow into the pipe  9  through the passage  41  and finally to the nozzle  11 . The piston  37  moves downward, until it reaches an annular surface  67  and a predetermined amount of water is displaced from the space  65  under a predetermined flow pressure.  
         [0025]    Before the piston  37  reaches the surface  67 , the lip seal  31  passes over a plurality of passage holes  34  of the housing  33 . Thus, if the piston  37  is in its lower position, water flows out into the flushing tank from the chamber  5  through the passage openings  34  and fills the flushing tank until the water level A is again reached. The water flowing out through the holes  34  is deflected in the downward direction with low noise by a ring  35  arranged on the outside of the housing  33 .  
         [0026]    When the water reaches the level of the nonreturn valve  22  during the filling of the flushing tank, a closing body  68  is subjected to buoyancy, as a result of which this valve is closed. As a result, the float  21  remains in its lower position until the water  50  reaches the water level A. The intake valve  4  correspondingly remains open until the flushing tank is again completely filled. When the water level A is reached, water enters the vessel  20  over its top edge, until it is finally filled again with water, and the float  21  moves the valve rod  24  upward and closes the passage opening  25 .  
         [0027]    When the intake valve is closed, the piston  37  returns to the position illustrated in FIG. 2, via the force exerted by the spring  39 . Communicating holes  81  allow water to flow from the tank into the chamber  64 , and the chamber  65  is again filled with water through the non-return valve  36 .  
         [0028]    The state shown in FIG. 2, in which the flushing tank is ready for the next flushing, is thus again reached. As is apparent from FIG. 2, an overflow edge  71  of the valve pipe  16  is arranged below the holes  34  in the housing  33 . A so-called water separation, which has the action of an anti-vacuum device and prevents dirty water from being drawn back into the pipeline water, is thus achieved.  
         [0029]    In a preferred embodiment, a time delay brought about by the control device  54  is set such that flushing water is released through the nozzle  11  when the water entering the bowl  56  through the channel  51  has reached the arch  46 . When the lip seal  31  passes the openings  34  in the housing  33 , the incoming water flows freely into the tank  8 , and the downward pressure on the cylinder  30  is reduced. As such, the time during which water is discharged through the nozzle  11  is relatively short.  
         [0030]    The foregoing merely illustrates the principles of the invention. It will thus be appreciated that those skilled in the art will be able to devise various arrangements which, although not explicitly described or shown herein, embody the principles of the invention and are thus within the spirit and scope of the following claims.