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PRIORITY CLAIM 
     This is a U.S. national stage of application No. PCT/CH99/00507, filed on Oct. 27, 1999. Priority is claimed on that application and on the following application: Country: Switzerland, Application No.: 2187/98, Filed: Oct. 29, 1998. 
    
    
     TECHNICAL FIELD 
     The invention relates to an upwardly directed douche on a seat of a toilet bowl. 
     PRIOR ART 
     U.S. Pat. No. 2,875,450 discloses an upwardly directed douche of the type mentioned above which, in the seat, has a plurality of douche heads which can be extended into the rinsing position. The douche heads are connected, via a line, to a water heater which is designed as a flow heater and is arranged in the seat. The flow heater has a pipe in which a heating element is arranged. For temperature control, use is made of a mechanically adjustable needle valve which restricts the flow rate of the rinsing water. This design has decisive properties which prevent the intended use from being realized in practice. The flow heater supplies cold water at the beginning of the rinsing operation and then either excessively cold or excessively hot water, since precise adjustment, in particular of the needle valve, is not possible. Pressure fluctuations in the water system thus result in temperature fluctuations or even in overheating of the rinsing water. Moreover, the seat is cold in the rest position since it can only be heated when rinsing water flows through the flow heater. The heating operation, however, usually only takes place upon completion of use, once the seat has already been heated by the user&#39;s body heat, and further heating would no longer be necessary at all. 
     There is also then the risk of the seat, with the flow heater active, becoming too hot. Finally, the upwardly directed douche is a closed system in which it is possible for water to be returned from the flow heater and for waste water possibly to be taken in from the toilet bowl. 
     CH-A-453 242 discloses a further upwardly directed douche with a douche head which can be pivoted into the rinsing position. This upwardly directed douche has proven very successful. The disadvantage, however, is that the upwardly directed douche is of relatively voluminous construction since the water heater and various control elements are fitted laterally on a seat carrier and take up a lot of space. 
     DESCRIPTION OF THE INVENTION 
     The object of the invention is to improve an upwardly directed douche of the type mentioned in the introduction. 
     Pursuant to this object, and others which will become apparent hereafter, one aspect of the present invention resides in an upwardly directed douche for a seat of a toilet bowl, which douche comprises a toilet seat, a douche head which can be extended into a rinsing position, a water heater in the seat, and a line that connects the douche head to the water heater. The water heater has a water chamber at least in a front part of the seat, an electric heating element arranged in the water chamber and a thermostat operatively connected to the heating element so as to control the heating element. Since the water heater arranged in the seat is designed as a water chamber with an electric heating element rather than as a flow heater, decisive advantages are attained along with a small, compact overall volume. The water chamber forms a system which has a relatively large volume and, in contrast to a flow heater, which only heats in the course of water consumption, is heated even when there is no need for any hot water. This allows straightforward and more accurate temperature regulation which can bring the water volume to the desired temperature and keep it there. The temperature regulation is unaffected by pressure fluctuations in the water supply and prevents the water from being detrimentally overheated. Hot water at the desired temperature is thus always immediately available for the rinsing operation over a relatively long period of time and the seat is already heating to a comfortable temperature for use. 
     According to another embodiment of the invention, the water heater may also have a safety thermostat, which is adjusted to the maximum admissible temperature. 
     It is possible, in principle, for the water supply and water discharge lines of the water heater to be arranged at any desired location on the seat. However, in order to prevent air-bubble formation in the water chamber, pursuant to another aspect of the invention, the douche head has openings located substantially at a highest point of the water chamber. 
     According to a further embodiment, the upwardly directed douche is provided with a line separator and a control valve, these being combined equiaxially, according to the invention, to form a bar-like structural unit. This produces a small structural unit which may readily be arranged in the rear part of the seat. In still another embodiment of the invention the line separator has a control piston which can be displaced in a cylinder part and has a coaxial injector through-passage with a nozzle directed towards a chamber which is connected to the water heater via a non-return valve. A spring is provided so as to prestress the control piston into a rest position in which, in an absence of water pressure, a connection between the control valve and the injector through-passage is interrupted by the control valve and the chamber is connected to a line which opens out into the toilet bowl and is closed when the control piston, with the control valve open, is displaced into a switching position. The non-return valve is directed toward the chamber and can be opened by an injector jet from the injector through-passage. This non-return valve prevents the hot water from being able to empty out of the water chamber, and pass into the water supply line, in an undesired manner. 
     It is possible for the douche head to be extended, for example, by a suitable push-button control means or a servo mechanism. 
     In still another embodiment of the invention an actuating lever is arranged laterally on the seat and connected to a pivot pin arranged on the seat and connected to the douche head so that the douche head can be extended by the actuating lever. This actuating lever provides straightforward and reliable actuation of the douche head. In a further embodiment an eccentric is arranged on the pivot pin of the douche head. A coupling device connects the eccentric to the control valve in terms of drive. The coupling device has a channel which is arranged between the eccentric and the control valve and is filled with contact elements for passing on control pulses from the eccentric to the control valve. This provides an effective, space-saving construction of the coupling device. 
     A cost-effective and compact construction is provided by another embodiment of the invention in which the seat has two rear articulations about which the seat can be swung up. Each articulation includes an articulation bolt. Each of the articulation bolts has either a water supply line or an electric supply line arranged therein. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Exemplary embodiments of the upwardly directed douche according to the invention are described in more detail hereinbelow with reference to schematic drawings, in which: 
     FIG. 1 shows a plan view of a seat of a toilet bowl with an upwardly directed douche; 
     FIG. 2 shows the control part of the upwardly directed douche in detail form, on a larger scale and partly in section, the bottom half showing a control valve and a line separator in the rest position and the top half showing said control valve and line separator in the actuated position; and 
     FIG. 3 shows a plan view of a modified seat with an upwardly directed douche. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1 shows a seat  2  which is fastened on a toilet bowl (not illustrated) via two rear articulations  4  and  6 . Each articulation  4 ,  6  contains a suitable braking device, for example in accordance with CH-A-453242, in order to ensure that the seat  2  is tilted downwards in a controlled manner. The upwardly directed douche contains a douche head  8  which is arranged on a pivot lever  10  and can be pivoted by means of a pivot pin  12 , about an axis  14  located in the seat, from the rest position, which is shown in the figure, into an operating position, which is not illustrated specifically. In the operating position, the douche head  8  is extended into a rinsing position located in the central region of the toilet bowl and/or of the seat and is oriented upwards, i.e. approximately perpendicular to the drawing plane, in order to direct a douche jet towards the anal and/or genital region of a user. The pivot pin  12  is actuated by means of an actuating lever  16 . The pivot pin  12  also contains a channel  18 , which connects the douche head  8  to a water heater  22  via a line  20 . 
     The water heater  22  is formed by a water chamber  24  which is arranged in the seat  2  and into which the line  20  opens out. An electric heating element  26  is arranged in the water chamber  24 . A thermostat  28 , which can preferably be regulated and likewise engages in the water chamber, makes it possible to adjust the water temperature in the water chamber  24 . A safety thermostat  30  is likewise connected to the water chamber  24  and restricts the maximum admissible level to which the water in the water chamber  24  can be heated. The thermostats and the associated control means are of electronic design and allow very accurate temperature regulation, for example to an operating temperature of 38° C. or 43° C. for the maximum admissible temperature. 
     The water heater  22  is fed by way of a structural unit  32  which is designed multifunctionally, for regulating the quantity and pressure of the supply water, as a line separator for preventing used water from being taken back into the water supply line  38  and for preventing hot water from running out of the water heater  22  in an undesired manner. A line separator  34  and a control valve  36  are arranged equiaxially one behind the other. Connected to the structural unit  32  is a water supply line  38  which is fed in from the outside through an articulation bolt  40  of the articulation  4  of the seat  2 . Analogously, an electric supply line  42  is fed in from the outside through the articulation bolt  44  of the other articulation  6 . The control valve  36  is connected for actuating purposes, via a coupling device  46 , to an eccentric  48  on the pivot pin  12 , which is pivoted by the actuating lever  16 . 
     The structural unit  32 , which comprises the line separator  34  and the control valve  36 , is illustrated in more detail in FIG.  2 . The structural unit  32  has a cylindrical housing  50  in which a first cylinder part  52  and a second cylinder part  54  are separated from one another by a central wall part  56 . The first cylinder part  52  belongs to the control valve and contains a piston  58 , which is fastened on a piston rod  60 . The latter bears a conical valve element  62  which is arranged in a cutout  64  in the central wall part  56 . The water supply line  38  opens out into the cutout  64 . A spring  66  which is arranged on the side directed towards the valve element  62  prestresses the piston  58 , and thus the valve element  62 , against a valve seat  68  and retains the valve in a closed position. On that side of the piston  58  which is located opposite the valve element  62 , a spring plate  70  is mounted in an axially displaceable manner on the piston rod  60  and is prestressed by means of a spring  72  against a stop  74  on a supporting sleeve  75  on the piston rod  60 . The spring  72  is supported on the piston  58 . Acting on the spring plate  70  is an actuating element  76 , which is connected to the pivot pin  12  and the actuating lever  16  via the coupling device  46 . Said design means that the control valve  36  is configured as a pressure-reducing valve as well as a quantity-reducing valve. By virtue of the actuating element  76  being actuated, first of all the spring  72  is compressed and the valve element  62  remains closed. It is only when the water pressure and the prestressing force of the spring  66  are exceeded that the valve element  62  is opened. The valve element then remains open until the prestressing force of the spring  72  is greater than the water pressure in the water supply line  38  and the prestressing force of the spring  66 . The control valve  36  is connected to the line separator  34  via at least one connecting channel  78  in the wall part  56 . 
     The line separator  34  has a control piston  80  which can be displaced in the second cylinder part  54  and, in its central region, contains a coaxial injector through-passage  82 , of which the nozzle  84  is directed towards a chamber  86  which is connected to the water heater  22  via a connecting line  85 . In the absence of water pressure, a spring  88  prestresses the control piston  80  into the rest position, against the valve seat  87 , and thus closes the connecting channel  78  between the control valve  36  and the injector through-passage  82 . In this rest position, the control piston  80  opens a through-passage  89  from the chamber  86  of the control piston  80  to an annular channel  90  and a line  92  which opens out into the toilet bowl, as a result of which the line channelling between the water supply line  38  and the water heater  72  is separated. In the case of any implosion in the water supply line  38 , it is not possible, on account of the non-return valve  94  described hereinbelow, for any water to be taken back into the water supply line  38  from the water heater and the downstream douche head  8 ; rather, only air can be taken in via the line  92 . For this purpose, the mouth opening of the line  92  is arranged freely above the water level in the toilet bowl such that it cannot take in any water from the toilet bowl either. The line separator  34  also contains the non-return valve  94 , which is arranged in the chamber  86 . The non-return valve  94  is formed by a sleeve  96  which is arranged in the chamber  86  and on which the spring  88  is supported. Arranged in the sleeve  96  is a valve element  102  which is prestressed against a valve seat  100  by means of a spring  98  and is opened by the water stream from the nozzle  84  of the injector through-passage  82  and releases the flow to the connecting line  85 . 
     FIG. 3 shows a further exemplary embodiment of a seat which has an upwardly directed douche and corresponds essentially to that from FIGS. 1 and 2, so that reference is made to what has been said above. The same parts are provided with the same designations. The modified features are indicated by the index a. 
     The heating element  26   a  is designed as a heating coil which extends essentially over the entire length of the water chamber  24   a . The heating coil  26   a  is connected to a control unit  104  which is arranged in the seat  2   a  and to which the thermostat  28   a  is also connected, the measuring head  106  of said thermostat extending more or less into the foremost region of the seat  2   a . The connecting line  85   a  for the water supply from the structural unit  32  to the water heater  22   a  opens out approximately into the first third of the length of the water chamber  24   a . The line  20   a  from the water chamber  24   a  of the water heater  22   a  has in each case one opening  108 ,  110  at the ends of the water chamber  24   a , these openings being located at the highest point of the water chamber  24   a  in order to discharge from the water chamber  24   a  any air bubbles produced. 
     The pivot lever  10   a  with the douche head  8  is located, in the retracted state, in a chamber  112  which is open at the bottom. The latter allows the douche head  8  to be cleaned by means of the water which overflows through the douche head during heating of the water in the water heater  22   a.    
     The coupling device  46   a , which serves for controlling the valve structural unit  32  by way of the pivot lever  10   a , contains a curved channel  114  arranged between the eccentric  48  and the control valve  36 . Said channel is filled with contact elements  116 , for example balls or pressure plates, of which the diameter is adapted essentially to the internal diameter of the channel  114 . The contact elements  116  are connected to the eccentric  48  via a first push rod  118  and to the control valve  36  via a second push rod  120 . It is thus straightforwardly possible for the control pulses of the eccentric  48  also to be passed on to the control valve  36  via a curved path. In the example of FIG. 3, the axis  14  of the pivot pin  12  and the axis  122  of the pivot lever  10   a  of the douche head are arranged in an offset manner. An eccentric stub  124  of the pivot pin  12  serves for carrying along the pivot lever  10   a.    
     As further embodiments which are not illustrated, it is possible for the water supply and/or power supply lines, rather than being arranged through the articulations, to be arranged independently of said articulations. In order to save power, it is possible to provide a toilet-seat lid which actuates a contact such that the water heater is only activated when the toilet-seat lid is open. Following opening of the lid, the heating element briefly heats the water in the chamber and the seat in order to provide a warm seat for the user. 
     The novel upwardly directed douche is distinguished by a very compact construction and, in practice, takes up no more space than a normal toilet seat. Furthermore, the upwardly directed douche is extremely straightforward since, rather than requiring any pumps, it functions solely by way of the control of the water pressure and the injector nozzle. The line separator forms an open system which prevents water from being taken back in from the water heater and from the toilet bowl. Furthermore, the heated water chamber in the seat achieves a seat which is warm for use and provides optimally heated water for the douche, a largely constant temperature being ensured and overheating being avoided. Heating-up of the water chamber produces a positive pressure which channels hot water to the douche head and helps to clean the latter. The novel upwardly directed douche is also suitable, in particular, for the subsequent replacement of an existing seat by the seat according to the invention with the upwardly directed douche installed therein, with the result that existing toilets can easily be retrofitted with an upwardly directed douche. 
     Thus, while there have been shown and described and pointed out fundamental novel features of the present invention as applied to a preferred embodiment thereof, it will be understood that various omissions and substitutions and changes in the form and details of the devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit of the present invention. For example, it is expressly intended that all combinations of those elements and/or method steps which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the invention. Substitutions of elements from one described embodiment to another are also fully intended and contemplated. It is also to be understood that the drawings are not necessarily drawn to scale but that they are merely conceptual in nature. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.

Summary:
A shower head ( 8 ) is disposed in a ring-shaped seat ( 2 ) and connected via a conduit ( 20 ) to a warm water preparation device ( 2 ) that is also arranged in said seat ( 2 ). The warm water preparation device ( 2 ) is arranged at least in the front part of the seat ( 2 ) and has a water chamber ( 24 ) in which an electric heating element ( 26 ) and a thermostat ( 28 ) controlling said element is arranged. It is possible to regulate the temperature in a simple and precise manner and also makes the seat warmer for the user.