Patent Publication Number: US-2004040075-A1

Title: Device for cleaning a toilet seat

Description:
[0001] The invention relates to a device for cleaning a toilet seat.  
       [0002] A system for the automatic cleaning of a toilet seat is known from U.S. Pat. No. 5,806,105. The system comprises a slidable and rotatable toilet seat which can be moved between a front and a rear position. Furthermore, a motor is provided which turns the toilet seat about a vertical circulating axis by means of a gear wheel engaging in the underside of the toilet seat. When the toilet seat is turned, the surface of the seat is cleaned by means of a cleaning unit, the waste water being able to flow off into a tank situated below the cleaning unit. After the toilet seat has been cleaned, it is moved into the front position and positioned on the rim of the toilet bowl.  
       [0003] DE-A 1 779 823 relates to a device for cleaning and sterilizing the seat of toilet bowls, comprising a cleaning element on an articulated transport element which is connected via a gearing to an electric motor, the transport element passing through a path which corresponds to at least a part of the shape of the seat, so that the cleaning element runs over the surface of the seat and thereby cleans and sterilizes it.  
       [0004] DE-C 214 183 A relates to a toilet bowl having a seat which is rotatable in its plane and cleans itself automatically when rotating. The seat turns automatically by means of a waterwheel inserted into the flushing line.  
       [0005] A toilet having a flushing device and a self-cleaning toilet seat can be found in DE 81 03 218 U1. The toilet seat is rotatable, a device for cleaning the seat surface extending over a segment of the toilet seat. The drive mechanism for moving the toilet seat comprises a driving wheel or a water turbine.  
       [0006] According to FR 2 761 253 A1, to clean a toilet seat, it is turned by a rotor driven by water power.  
       [0007] A cleaning device for toilet seats is known from DE-C 510 241. In this case, a brush is moved along the seat by means of a cord pull. The cord pull itself is set into motion by means of a crank.  
       [0008] According to EP 0 221 017 B1, to automatically clean a toilet seat, a device for automatically cleaning a toilet seat is proposed in which a seat is turned toward a cleaning device by means of electric motors.  
       [0009] The disadvantages to be noted in the known devices are, on the one hand, the expensive drive and, on the other hand, a mechanical susceptibility to failure.  
       [0010] Based on the foregoing, the object of the present invention is to improve a device for cleaning a toilet seat of the aforementioned type in such a way that a flawless cleaning of the toilet seat is possible with a simple construction and a more favourable energy consumption.  
       [0011] According to the invention, the object is essentially achieved in that the device has a mobile cleaning unit whiuch is movable along the toilet seat by means of water power. According to the invention, the energy released when water flows into the water tank is used to move the mobile cleaning unit along the toilet seat. Due to its smaller mass in comparison to that of a toilet seat, the mobile cleaning unit offers the advantage that the construction is simplified and that a drive having a more favourable power is provided.  
       [0012] In particular, the device according to the invention is distinguished by a hydraulic drive unit which has a cylinder in which is located a piston which is displaceable by water power and which is connected with the mobile cleaning unit by drive means. In this case, the drive unit is preferably located in a water tank, such as a flush tank, so that water flowing into the hydraulic drive unit can subsequently be drawn off into the flush tank.  
       [0013] First, inflowing water is conveyed into the cylinder, as a result of which the piston moves in a first direction and the mobile cleaning unit moves from a first position along the toilet seat into a second position. A return movement of the piston is then started by diverting the water flow, as a result of which the cleaning unit then travels from the second position back into the first position.  
       [0014] The cylinder is designed in such a way that it has an upper and a lower water inlet as well as an upper and a lower water outlet, the water inlets being connected with a water supply pipe via a valve. The water outlets each have a valve. The aforementioned arrangement enables the back-and-forth movement of the mobile cleaning unit.  
       [0015] Cords connected with the piston movably mounted in the cylinder are provided as drive means, the cords preferably being connected with the mobile cleaning unit via a gearing or a conversion unit such as guide pulleys and/or cord lines. Preferably, the piston is connected with a cord at each of its ends, the cords passing through an upper and a lower front wall of the cylinder, respectively. Due to the conversion unit, the force exerted on the piston by the force of the water can be transmitted to the cleaning unit.  
       [0016] In a further preferred embodiment of the device, it is provided that the conversion unit is in the form of conversion pulleys, the conversion pulleys having two small cord pulleys with a diameter d, where preferably 10 mm≦d≦20 mm, in particular d=15 mm, and two larger cord pulleys with a diameter D, where preferably 70 mm≦D≦110 mm, in particular D=90 mm. The pulleys are fixedly connected to one another and arranged along an axis. The conversion pulley offers the advantage that the stroke travelled by the piston is stepped up by a factor F where, in particular, 3.5≦F≦11. To obtain the conversion, the two cord ends connected with the piston are each fastened to one of the smaller cord pulleys. This cord pulley is configured in such a way that the two cords can be wound and unwound separately from one another in different paths. The smaller cord pulley is securely connected with a second cord pulley on which there are also two cord paths which, however, have the larger diameter. The cord wound on the larger cord pulley is fastened to the cleaning unit which thus always moves through F-times the movement of the hydraulic piston. The two cord lengths on each of the pulleys make it possible to move the cleaning unit over the toilet seat in both directions.  
       [0017] The mobile cleaning unit itself has a substantially U-shaped geometry which comprises a first leg that is parallel or essentially parallel to an underside of the toilet seat and a second, upper leg that extends parallel or essentially parallel to a surface of the toilet seat to be cleaned.  
       [0018] On the lower leg, there are guide rollers which engage in a guide groove located on the underside of the toilet seat in order to thus ensure that the mobile cleaning unit is guided along the toilet seat. Cleaning means such as, for example, a rubber wiper, a brush, a sponge as well as preferably a liquid container are arranged on the upper leg. It is thereby provided that the liquid container has openings for discharging a cleaning fluid which is applied to the surface of the toilet seat to be cleaned.  
       [0019] Furthermore, the invention provides that the liquid container for the cleaning fluid is connected with a water source and/or a reservoir for cleaning agents in the first position of the mobile cleaning unit in order to fill water and/or cleaning agent into the container when needed.  
       [0020] It is provided that the mobile cleaning unit is housed by a receptacle in the first position (park position) so as to be protected in order, on the one hand, to avoid odour problems and, on the other hand, to ensure increased safety. To drive the mobile cleaning unit, the driving cord is situated in the guide groove on the underside of the toilet seat, preferably via rollers.  
       [0021] The lower leg of the mobile cleaning unit is preferably supported twice on the underside of the toilet seat, whereby a first support takes place in the peripherally extending guide groove and a second support on the underside of the rim of the toilet seat, preferably by means of ball rollers. On the upper side, the mobile cleaning unit is supported by the cleaning elements, such as sponge, brush, wiper, so that a good guidance is ensured overall. 
     
    
    
     [0022] Further details, advantages and features of the invention can be found not only in the claims, the features that can be found therein—alone or in combination—but also in the following description of a preferred embodiment that can be found in the drawings.  
     [0023]FIG. 1 shows a perspective illustration of a toilet with toilet seat, water tank and integrated cleaning unit,  
     [0024]FIG. 2 shows a perspective illustration of the water tank with drive unit,  
     [0025]FIG. 3 shows a perspective illustration of the drive unit,  
     [0026]FIG. 4 shows a sectional illustration of the toilet seat with cleaning unit,  
     [0027]FIG. 5 shows a sectional illustration along the section line A-A of FIG. 4,  
     [0028]FIG. 6 a  shows a bottom view of the toilet seat,  
     [0029]FIG. 6 b  shows a section of the bottom view of the toilet seat of FIG. 6 a,    
     [0030]FIG. 7 shows a perspective illustration of a conversion unit,  
     [0031]FIG. 8 shows a schematic illustration of a control circuit for the drive cylinder,  
     [0032]FIG. 9 shows a perspective illustration of the mobile cleaning unit in its park position, and  
     [0033]FIG. 10 shows a flow chart for controlling the device for the automatic cleaning of a toilet seat. 
    
    
     [0034] In a perspective illustration, FIG. 1 shows a toilet  10  with a toilet seat  12  to be cleaned as well as an associated water tank  14  with a receptacle  16  for a mobile cleaning unit  18 . According to the invention, the mobile cleaning unit  18  is actuated by a hydraulic drive unit  20  situated in the water tank  14 , so that the mobile cleaning unit  18  can travel along the toilet seat.  
     [0035] The hydraulic drive unit  20 , shown in FIGS. 2 and 3, comprises a cylinder  22  which is shown in FIG. 3. A piston  24  is longitudinally movably arranged in the cylinder  22 . Actuating means such as cords  30 ,  32  are situated on the ends  26 ,  28  of the piston  24 , the actuating means passing through the end closures  34 , 36  of the cylinder and being connected via guide rollers  38 , 40  with a conversion unit  42 ,  44  which is in the form of a pulley block in the illustrated example and arranged on both sides of the drive unit  20 .  
     [0036] The cylinder  22  has a first upper inlet opening  46  and a second, lower inlet opening  48  which are each connected with a water supply pipe  56  via a connecting pipe  50 ,  52  and a valve  54 .  
     [0037] Furthermore, a first upper outlet opening  58  and a second lower outlet opening  60  are provided via which the water which flowed into the cylinder  22  is ejected into the water tank  14 . The outlet openings  58 ,  60  each have valves  62 ,  64 .  
     [0038] Due to the movement of the piston  24  inside the cylinder  22 , the mobile cleaning unit  18  is moved back-and-forth from a first position, preferably within the receptacle  16 , into a second position. During the movement, the mobile cleaning unit  18  travels completely, or almost completely, over the toilet seat  12  and subsequently returns into the first position.  
     [0039]FIG. 4 shows a cross-section of the mobile cleaning unit  18  as well as the toilet seat  12 . The mobile cleaning unit  18  is essentially U-shaped and comprises an upper leg  66  and a lower leg  68  which are connected to one another via a cross piece or a connecting element  70 . A guide element  72 , which extends from the lower leg  68 , engages in a guide groove  74  extending in the lower side  76  of the toilet seat  12  and, for example, milled or moulded. The guide element  72  comprises ball bearings  78 ,  80  which bear on an inner wall  82 , in particular a bottom wall, of the guide groove  74 . Furthermore, rollers  84 ,  86  are provided which essentially have a diameter that corresponds to the width of the guide groove  74 . This ensures a lateral guidance of the mobile cleaning unit  18 . Furthermore, the rollers  84 ,  86  serve to receive drive cords  88 ,  90  which are led within the guide groove  74  and each connected with one of the pulley blocks  42 ,  44 .  
     [0040] As a further support on the toilet seat  12 , a further pulley  92 , which bears on the underside  76  of the toilet seat  12  and which is to prevent the mobile cleaning unit  18  from tipping, extends from the lower leg  68  of the cleaning unit  18 . Moreover, the rollers  78 ,  80 ,  92  ensure a frictionless movement of the mobile cleaning unit, so that, on the whole, low forces are employed.  
     [0041] To clean a surface  94  of the toilet seat  12  to the desired extent, cleaning means such as a sponge or brush  96 , wipers  98  and/or a container  100  for cleaning agents such as a cleaning fluid or disinfecting liquid are integrated in the upper leg  66  of the cleaning unit  18  which extends essentially parallel to the surface  94  of the toilet seat  12  to be cleaned. To apply a liquid contained in the container, openings  102  are provided via which the cleaning agent can drip onto the surface  94  to be cleaned. When the cleaning unit  18  is moved, the liquid is absorbed by the sponge  96 , so that an effective cleaning can take place. The remaining liquid is subsequently removed from the surface  94  by wipers  18 .  
     [0042]FIG. 6 shows an underside of the toilet seat  12  with the guide groove  74  within which the cords  88 ,  90  extend. To prevent the cords  88 ,  90  from being in contact with the guide groove  74  over the entire distance, cord pulleys  104  are inserted into the guide groove  74 , so that the contact surface is limited to the few contact points with the rollers  104 . This reduces the friction considerably.  
     [0043] Preferably, the toilet seat  12  is essentially designed as a closed circular body  106  which can be articulated to an end piece  108  via which the cleaning unit  18  can travel into the receptacle  16 . Preferably, an intermediate piece  110  extends between the end piece  108  and the actual toilet seat  106 , the intermediate piece  110  being alternatively designed as a removable intermediate piece, as a rubber connection or as a joint. The intermediate piece  110  is designed in such a way that, when the toilet seat  12  is lifted, the driving cords  88 ,  90  are not affected in their travel.  
     [0044]FIG. 7 shows a preferred embodiment of a conversion unit  42  in the form of a conversion roller. The stroke through which the piston  24  travels is stepped up by a factor F such as  6  via the conversion unit  42 , in the present embodiment designed as a conversion pulley. To obtain the conversion F, cord ends of the cords  30 ,  32 , which are connected with the piston  24 , are fastened to a cord pulley  152  having two grooves with a small diameter, e.g. with the diameter d=15 mm. The cord pulley  152  is designed in such a way that the two cords can be wound or unwound separately from one another in different paths or grooves  154 ,  156 . Furthermore, the cord pulley  152  is fixedly connected with a second pulley  158  on which there are also two paths or grooves  160 ,  162  for the driving cords  88 ,  90 . The diameter of the larger pulley is e.g. D=90 mm. The wound cords  88 ,  90  are fastened to the cleaning unit  18  which covers six times the path of the hydraulic piston in the embodiment. It is possible to let the cleaning unit  18  travel in both directions over the toilet seat  12  with the two cord ends on each roller. In this case, the cleaning takes place in such a way that the cleaning unit  18  in the first position (park position) is filled with a mixture of cleaning fluid and tap water after the water tank  14  has been emptied and moved by the drive unit over the toilet seat.  
     [0045]FIG. 8 shows a schematic design of a control unit for driving the cleaning unit  18 . The essential elements relating to the drive cylinder  22  were already described in association with FIGS. 2 and 3. The drive unit  20  is connected via the pipe  56  with a valve  112  which is connected at the inlet side with a water supply system via a supply pipe  114 . At the outlet end, the valve  112  has a pipe  116  which is designed to supply water for the container  100  situated in the cleaning unit  18 . A further outlet  118  is used to fill the water tank  14 .  
     [0046] Furthermore, to fill the container  100  integrated in the cleaning unit, a reservoir  120  is provided to accommodate a cleaning fluid, the reservoir being connected with the cleaning unit in the park position via a pipe pipe  122  and controlled by a valve  124 .  
     [0047] The cleaning should take place in such a way that the cleaning unit  18  which is in the park position is filled with a mixture of cleaning fluid and tap water after the water tank  14  has been emptied and then moved over the toilet seat  12  by means of the drive unit  20 . The filling capacity of the container  100  integrated in the cleaning unit  18  is sized such that it is used up after it has travelled over the toilet seat  12  once. As soon as the cleaning unit  18  has travelled over the entire toilet seat  18  [sic], the piston  24  moving in the drive cylinder and controlled by the valve  54  is acted upon by pressure in the opposite direction, as a result of which the cleaning unit travels back and the previously wetted surface  94  is dried with the rubber wiper  98 . After the cleaning, the cleaning unit  18  is again in its park position and remains there until it is used again.  
     [0048] The valves  54 ,  62 ,  64 ,  112 ,  124  which are employed can be designed as electric nic switch units which are preferably provided with an energy supply, such as a solar cell or storage battery.  
     [0049] A preferred procedural sequence is shown in FIG. 10. In a first step  126 , a flush knob is actuated. In a further step  128 , the contents of the water tank are emptied into the toilet, whereby the water supply is switched on in a step  130  by means of a mechanism known per se.  
     [0050] According to the invention, the valve  112  and the valve  124  are first opened in a procedural step  132 , so that water and cleaning fluid can flow into the container  100  integrated in the cleaning unit, the cleaning unit being filled in the procedural step  134 .  
     [0051] After this process has been completed, the valve  124  is closed in a further step  136  and the valve  112  is switched over, so that the drive unit  20  is provided with water via the supply pipe  56 . The valve  54  is thereby actuated in such a way that the cylinder  22  is supplied with water via the pipe  52 . The outlet valve  62  is closed in this procedural step  136 , the outlet valve  64  being opened so that the water contained in the cylinder  22  can flow out into the water tank  14 .  
     [0052] The water flows into the cylinder  22  and moves the piston  24 , so that the movement of the cleaning unit  18  is started in a step  138 . In a subsequent step  140 , namely when the piston  24  has reached its end position, the valve  54  is switched over, the valve  62  opened and the valve  64  closed, as a result of which the water flow through the pipe  50  moves the piston  24  in opposite direction, so that the return movement of the cleaning unit  18  is started in step  142 . As soon as the cleaning unit  18  has reached its park position, the valve  112  is switched over in step  144 , so that the flush tank is filled via the pipe  118  in step  146 . Preferably, a signal lamp can be switched on in step  148 . After the tank  14  has been filled, the water supply is automatically switched off in a last step  150 .