FLUSHING FITTINGS FOR A FLUSHING CISTERN

Abstract: The present invention relates to flushing fittings having a bottom valve body (13), which is fixedly connected to or formed integrally with a float (22). The bottom valve body is adapted to seal against a valve seat (12) with a sealing area and to be lifted from the valve seat by means of an actuation mechanism (20). The actuation mechanism comprises a flush actuation means (24). The float (22) has such a volume that its buoyancy is always greater than the sum of all downwards directed forces acting on the valve body, the float and the means connected with the float. The actuation mechanism (20) has a retaining device (25) which is arranged to prevent the float (22), in the rest position of the flushing fittings, from lifting up the bottom valve body (13) from the valve seat (12). The flush actuation means (24) is arranged to release the retaining device (25) when flushing.

Description: FLUSHING FITTINGS FOR A FLUSHING CISTERN Technical Field The present invention relates to flushing fittings having a bottom valve body, which is fixedly connected to or formed integrally with a float, and which is adapted to seal against a valve seal with a sealing area and to be lifted from the valve seat by means of an actuation mechanism, which comprises a flush actuation means. Background Art Traditionally, flushing from flushing cisterns is carried out by mechanical actuation of the flushing, i.e. by acting mechanically on an actuation mechanism, for instance, by pushing a button or pulling a knob or a string in order to lift the bottom valve body from the valve seat. This activates the flushing when a certain amount of force is exerted on the actuation mechanism to overcome downwards directed forces on the bottom valve body. In certain respects, it is desirable to actuate the flushing by applying only little force. This is the case, for instance, when children or handicapped are flushing. Moreover, the trend is increasingly towards electronic actuation of the flushing, i.e. the flushing is actuated by an electric signal by acting on a sensor. In most cases, an IR beam is interrupted in the vicinity of the flushing cistern, which generates an electric signal which in turn actuates the flushing. In this connection, problems arise when converting the electric signal into such forces as are required for actually actuating the flushing . It goes without saying that electronic actuation of the flushing requires the supply of electric current by battery power or connection to the mains. Both alternatives suffer from drawbacks. In battery operation, a limited amount of power is available for actuating flushing and therefore it is de- sirable to limit the current consumption. A great amount of force leads to high current consumption, which reduces the service life of the battery. This may require frequent changes of batteries, which of course is not desir- able. In the case of connection to the mains, more power is available and therefore it is not necessary to limit the current consumption. Mains connection is, however, more complicated, since electric installation is required in the immediate vicinity of the flushing cistern. In addition, the combination of water and electric power is not desirable for safety reasons. US-A-5 , 603 , 127 discloses a flushing cistern in which the flushing is activated by interrupting an IR beam. In order to develop a sufficient amount of force to actuate the flushing, a flushing motor is used. SE-C-502,377 discloses a flushing cistern which makes it possible to flush using optionally a great or a small amount of flushing water. In the device, use is made of catches to change between high-level and low- level flushing. EP-A-0 629 748 discloses yet another flushing cistern which makes it possible to flush using optionally a great or a small amount of flushing water. Also in this device, use is made of catches to change between high- level and low-level flushing. In addition, this flushing cistern has a vertically oriented coil, into which a metal part of the float rod extends upwards . When flushing, a current is supplied through the coil, which then pulls the float rod upwards, thus opening the bottom valve . There are different mechanical constructions for lifting the bottom valve body from the valve seat. GB- 2,167,531-A discloses a construction in which a float 10 is displaceable vertically on the one hand relative to an upward directed valve rod 7, which is fixedly connected to the valve body 5 of the valve and, on the other, rela- tive to an upward directed part of a valve housing 3. The float body 10 is fixedly connected to a housing, which is formed of a cap 18 and a sleeve 15 and in which a ferromagnetic disc 14 is mounted. In the rest position of the flushing mechanism, i.e. when the bottom valve is closed, the ferromagnetic disc rests on a magnet 13, which is fixedly mounted on the upper end of a central column 6, which is stationary relative to the valve seat 2 of the bottom valve. To actuate the flushing mechanism, use is made of a bellows 17, which is mounted inside the housing 15, 18 and which, by means of a control pin 19, acts on the upper end of the magnet 13 on the upper end of the central column 6. The device is such that the force exerted by the bellows must overcome the attractive force between the magnet 13 and the ferromagnetic disc 14 for the latter to be lifted straight up from the magnet 13. After that, the float 10 will lift the housing 15, 18, the bellows 17 and the disc 14 upwards and subsequently also contact a ring 8 at the upper end of the valve rod 7. In the continuing lifting motion, the valve plate 5 will be lifted up from the valve seat 2. In this lifting motion, perforation holes in the side wall of the valve housing 2, 3 are uncovered, so that water can flow into the valve housing and further out through the now open bottom valve 2, 5. In order to prevent the valve rod 7 with the attached valve body 5 from sinking down towards the valve seat when emptying the cistern, the valve rod 7 can have a float body 4 of its own, which floats up in the water, which is let into the valve housing 2, 3. Thus, in this prior-art device a magnetic attractive force is to be overcome by pulling two mutually attracting magnetic surfaces straight out from each other. JP- 9316962 discloses a valve device in which a ball-shaped valve body 3 is provided with a permanent magnet 2. The valve seat 10 ' has an electromagnet 1 which co-operates with the permanent magnet, thus retaining the valve body. When flushing, the poles of the electromagnet are changed by means of a change-over switch, so that the electromagnet will have the same magnetic pole as the permanent magnet . The magnets then repel each other so that the valve body is pushed away from the valve seat. US-939,123 discloses a complicated flushing device. To summarise, in this construction the weight v keeps the valve in an open position, when the flushing has been actuated, until the cistern is substantially empty. Summary of the Invention One object of the present invention is to obviate one or more of the above-mentioned drawbacks and provide new flushing fittings which allow actuation of the flushing by applying a small amount of force without the use of a flushing motor. The object is achieved by flushing fittings according to the invention, which have the features stated in the characterising part of the independent claim. The dependent claims define particularly preferred embodiments of the invention. In summary, the invention thus relates to flushing fittings having a bottom valve body, which is fixedly connected to or formed integrally with a float. The bottom valve body is adapted to seal against a valve seat with a sealing area and to be lifted from the valve seat by means of an actuation mechanism. The actuation mechanism comprises a flush actuation means. The float has such a volume that its buoyancy is always greater than the sum of all downwards directed forces acting on the valve body, the float and the means connected with the float. The actuation mechanism has a retaining device, which is arranged to prevent the float, in the rest position of the flushing fittings, from lifting up the bottom valve body from the valve seat. The flush actuation means is arranged to release the retaining device, when flush- ing, by causing a relative displacement of its locking surfaces along each other. One advantage of the invention is that the actuation of the flushing can be of non-contact type. Another advantage of the invention is that it is not necessary to provide a separate means to keep the valve in open position. Yet another advantage of the invention is that it is very well suited for use in electronic actuation of the flushing. Since only a small amount of force is required to actuate flushing, the power consumption will be low, which is advantageous for the service life of the battery in the case of battery operation. The invention can be used both for battery operation and mains connection. An additional advantage of the invention is that the amount of flushing water is adjustable by means of the vertical position of the float in the embodiment involving a float rod. Another advantage of the invention is that the construction is simple. Above-mentioned GB-2 , 167, 531-A is not based on the same principle as the present invention, since the lifting force of the float in this prior-art construction is just sufficient to lift itself, the housing 15, 18 and the components mounted in the same as well as the valve rod 7 and the valve body 4, 5. The filling degree of the cistern is set so as to be just sufficient to prevent these components from being lifted up relative to the valve seat against the action of the gravitational forces which are present due to the mass of these components. Since the valve body 4, 5 is accommodated in a valve housing 2, 3 and allows water to enter this valve housing only when perforation holes in the valve housing wall 2 have been uncovered after the upwards motion, there is no water column in this construction acting directly on the actual valve body 5 to press the same downwards into abutment against the valve seat 2. If such a water column had been present in this construction, it would have been necessary for the bellows to overcome both the magnetic force and the force exerted by this water column. The invention is based on a different principle on the one hand by the fact that the volume of the float body should be sufficient for its buoyancy always to be greater than the sum of all downwards directed forces acting on the valve body, the float and the means connected with the float due to the masses of the float and the means connected therewith and due to a maximally pos- sible water column which is located above the sealing area of the bottom valve body and acts against the valve body and, on the other, by the fact that the actuation mechanism should have a retaining device having two locking surfaces which act on each other and which at the initiation of the flushing process are relatively displaced along each other. Brief Description of the Drawings Below, the invention will be described in more detail with reference to the accompanying drawings, which show exemplifying embodiments of the invention. Fig. la is a partially cross-sectional front view of flushing fittings according to the present invention in their rest position. Fig. lb is a partially cross-sectional lateral view of the flushing fittings according to Fig. la in the rest position. Fig. lc shows an enlargement of a detail from Fig. lb. Fig. Id shows a float rod with a setting scale. Fig. 2 shows a view corresponding to that in Fig. la of the flushing fittings in flushing position. Fig. 3a is a partially cross-sectional front view of an alternative embodiment of the flushing fittings according to the present invention in their rest position. Fig. 3b is a partially cross-sectional lateral view of the flushing fittings according to Fig. 3a in the rest position. Fig. 3c shows an enlargement of a detail from Fig. 3a. Fig. 3d shows an enlargement of a detail from Fig. 3b. Fig. 4 is a view corresponding to the one in Fig. 3c and showing the flushing fittings when initiating flushing . Fig. 5 is a view corresponding to the one in Fig. 3c and showing the flushing fittings in the flush- ing position. Fig. 6 is a top view of the battery unit for the flushing fittings according to the invention. Fig. 7a is a view corresponding to the one in Fig. la and showing another alternative embodiment of the flushing fittings in Fig. la in the rest position. Fig. 7b is a lateral view of an enlargement of a detail from Fig. 7a in the rest position of the fittings. Fig. 8 is a perspective view of yet another alternative embodiment of the flushing fittings in Fig. la in the rest position. Fig. 9a is a front view of the flushing fittings according to Fig. 8 in the rest position. Fig. 9b is a view corresponding to the one in Fig. 9a and showing the flushing fittings when initiating flushing. Fig. 9c is a view corresponding to the one in Fig. 9a and showing the flushing fittings in the flushing position. Fig. 10 is a partially cross-sectional lateral view of the flushing fittings according to Fig. 8 in the rest position. Figs 11-15 show an electronic unit as an alternative to the construction shown in Fig. 6. Description of a Preferred Embodiment The invention relates to flushing fittings for a flushing cistern which is adapted to flush sanitary devices such as water closets, urinals and similar devices. The flushing fittings according to the present invention are mounted in a flushing cistern 1 having a bottom 2 and a lid 3, as appears from Figs 1-3. The lid rests on the upper outer edge of the cistern. The fittings are mounted in two holes in the bottom of the cistern. An inlet pipe 4 for flushing water extends through one of the holes. For sealing, use is made of a pipe socket 5, a seal 6 and a nut 7. The fittings comprise a bottom valve 8, whose lower portion 9 has the form of a pipe socket, which extends through the bottom of the cistern 2 and is sealed against the same by means of a nut 10 and a seal 11. In its upper end, the lower portion is formed with an annular seat 12. The seat is adapted to co-operate with a bottom valve body 13, which has an annular valve surface 14 with a shape complementary to that of the seat 12. Thus, the valve surface has a certain sealing area against the seat. The valve body 13 is guided to move substantially axially towards and away from the seat 12. To this end, use is made of guid- ing members 15, which are four in the shown embodiment and which extend upwards from the lower portion 9 to form a slightly conical guiding surface for the valve body 13. Other ways of guiding the valve body relative to the seat surface are feasible. The inlet pipe 4 is connected to an inlet valve 16, which is regulated by a float 17 in conventional manner for filling flushing water into the cistern, when the water level is below a certain filling level. When filling, the water runs downwards along an overflow pipe 18, which is fixedly connected to the lower portion 9 of the bottom valve. This overflow pipe supports the mechanism and thus constitutes the supporting member of the flushing fittings. In the example, the overflow pipe 18 is provided in prior-art manner with a coating or stocking 19, which serves to reduce the noise of the flushing water when filling the water cistern. At the upper end of the overflow pipe 18, the actuation mechanism 20 of the fittings is located. In one embodiment (not shown) of the invention, the bottom valve body is integrated with a float. In such an embodiment, there is no float rod. In the flushing fittings according to the invention which are shown in the Figures, there is a float rod 21 with a float 22. The float is settable in different vertical positions along the float rod to adjust the desired quantity of flushing water. The float rod preferably has a setting scale 23, as shown in Fig. Id, to facilitate the setting. Once the float is placed on the float rod in the desired vertical position, it does not move in relation to the float rod during operation. The float rod 21 is fixedly but not ne- cessarily rigidly connected to the bottom valve body 13. Prior-art flushing fittings are based on the principle that the float and the bottom valve body must be lifted up, by the action of an external force, from the valve seat when actuating flushing. In contrast, the flushing fittings according to the invention are based on the principle that it should be sufficient to release a retaining device when flushing. In fact, the float in the flushing fittings according to the invention constantly tends to lift up the bottom valve body from the valve seat by means of a greater force than the sum of all downwards directed forces acting on the valve body, the float and the means connected with the float due to the masses of the float and the means connected therewith and due to a maximally possible water column which is located above the sealing area of the bottom valve body and acts against the same. Thus, the float must be retained in the rest position of the fittings so as not to float up. When flushing, the retaining device is released, the float floating up and lifting the bottom valve body from the valve seat. A smaller amount of force is required to release the retaining device according to the present invention than what is required in prior-art technique to actively lift the float and the bottom valve body when actuating flushing. In the flushing fittings according to the present invention, flushing can thus be actuated by means of only a small amount of force without the use of a flushing motor . SE-C-502,377 and EP-A-0 629 748 disclose the use of catches. However, in these cases the catches are used to change between a great and a small quantity of flushing water. Figs la-lc show flushing fittings according to the present invention in their rest position, i.e. in the initial position of the actuation mechanism 20. The cistern is filled to the level indicated by F. In Fig. 2, the mechanism is shown in the flushing position. Both upwards and downwards directed forces act on the float 22, the valve body 13 and the float rod 21. The volume of the float determines the magnitude of the upward directed buoyancy. According to the invention, the buoyancy should always be greater than the sum of all downwards directed forces when the float is not retained. The following principles apply to the downwards directed forces. First, the force of a water column located above the sealing area of the bottom valve body acts downwards. The height of the water column varies with the water level in the cistern. The buoyancy of the float must be sufficiently great so as to compensate also for the maximally possible water column. Second, gravitation acts on both the mass of the float and on the masses of the means connected with the float. That stated above is essentially applicable without taking into account frictional losses, losses owing to vortex formation and to pressure variations due to different filling levels, also in the case of small changes of the same. Furthermore, the retaining device affects the balance of forces, since the retaining device pre- vents the float from lifting in the rest position of the fittings . Now suppose, as an arithmetical example, that the float and its fixedly connected components have a mass of 0.063 kg, that the water column above the sealing area of the bottom valve body is 0.23 m, and that the sealing area is 2.8 • 10 "3 m 2 . The water column then generates a downwards directed force of 6.4 N. The force of gravity acting on the float is m ■ g = 0.063 kg • 9.81 = 0.6 N. The upwards directed force must thus be greater than the sum of 6.4 N and 0.6 N. By means of a float having the volume 0.8 dm 3 , a buoyancy of 8 N is provided. This gives a security factor of 8/(6.4+0.6) = 1.14, which can be rounded off to 1.2 and which is considered to be a suffi- cient safety margin. The length, width and height of the float are adapted on the one hand to the space in the cistern and, on the other, to the opening of the cistern. The fittings are introduced into the cistern from above, and therefore the opening of the upper portion of the cistern determines the dimensions of the float . The float has a recess in the bottom, as shown in for instance Fig. la, which allows the float to be lowered to the lower end of the float rod in spite of the valve body 13. The trend is towards flushing using increasingly smaller amounts of flushing water. The embodiment of the invention shown in the Figures is adapted for flushing using a flushing water quantity of 6-8 litres. The shown shape of the float allows the amount of flushing water to be set at 6-8 litres. The recess is necessary in order to be able to flush out 8 litres. Other flushing water quantities are also possible using the principle according to the present invention. With reference to Figs 1-5, the flushing fittings thus comprise a bottom valve body 13 which is fixedly connected to or integral with a float 22. The bottom valve body is adapted to seal against a valve seat 12 with a sealing area and to be lifted from the valve seat by means of an actuation mechanism 20. The actuation mechanism comprises a flush actuation means 24. The float 22 has such a volume that its buoyancy is always greater than the sum of all downwards directed forces acting on the float and on the means connected with the float, also when the cistern is filled to its maximum level, and therefore the float would always be in its uppermost position if it was not retained. The actuation mechanism 20 has, however, a retaining device 25 which is arranged to prevent the float 22, in the rest position of the flushing fittings, from lifting up the bottom valve body 13 from the valve seat 12. The flush actuation means 24 is arranged to release the retaining device when flushing. The actuation mechanism 20 has a rocker arm 28 which has a first and a second leg. The first leg 29 supports the retaining device 25, and the second leg 30 supports the flush actuation means 24. The rocker arm 28 is arranged to pivot on a pin 35 which is anchored to the sup- porting member of the flushing fittings. In the embodiment which is shown in Figs 1-2 and 7a- 7b, the retaining device 25 comprises a locking boss 26 co-operating with a locking latch 27. In the embodiment which is shown in Figs 1 and 2, the locking latch 27 of the retaining device is arranged on the first leg 29 of the rocker arm, while the locking boss 26 is arranged on the upper end of the float rod 21. However, in the embodiment which is shown in Figs 7a-7b the locking latch 27 of the retaining device is arranged on the upper end of the float rod 21, while the locking boss 26 is arranged on the first leg of the rocker arm. With reference to Fig. 7b, it appears that both the locking boss 26 and the locking latch 27 are doubled, so that there is one locking boss on each side of the first leg 29 of the rocker arm 28 and two parallel locking latches which extend upwards from the upper end of the float rod. The object of the doubling is to in- crease the stability and operational reliability of the device . In the embodiment in Figs 1-2 and 7a-7b, the locking latch has an L-shaped slot 31 with a substantially hori- zontal part and a substantially vertical part. The locking boss 26 runs in the slot 31, the flushing fittings assuming their rest position, when the locking boss is in the substantially horizontal part of the L-shaped slot, and assuming their flushing position, when the locking boss is in the substantially vertical part of the L- shaped slot . In the embodiment of the invention which is shown in Figs 3-5, the retaining device 25 comprises a locking boss 32 and an abutment member 33 co-operating with the same. The bottom valve body 13 is fixedly connected to the float rod 21. The locking latch 32 is arranged on the upper end of the float rod, and the abutment member 33 is arranged on the first leg 29 of the rocker arm. The float rod can also in this embodiment be provided with a set- ting scale according to Fig. Id. In the shown embodiment, the flush actuation means 24 has a coil 40, which is fixedly connected to the supporting member and which has an iron core 41, and a magnet 42 arranged on the second leg 30 of the rocker arm. In the rest position of the fittings, the iron core is thus attracted by the magnet, which results in the second leg 30 of the rocker arm being retained at the iron core 41. When flushing, a current is transmitted through the coil 40, which generates an opposed magnetic field which reduces the attractive force between the permanent magnet 42 and the electromagnet 40, 41. The upwards directed force of the float is now greater than the attractive force of the magnet, and therefore the retaining device 25 allows the float to rise. In the embodiment according to Figs 1-2, the pivoting of the rocker arm 28 makes the locking latch 27 turn, thus giving the slot 31 a more upright position, as shown in Fig. 2. As a result, the locking boss 26 can leave the substantially horizontal part of the L-shaped slot and enter the substantially vertical part of the L-shaped slot. The upper side of the locking boss 26 has a sub- stantially horizontal surface 26a which, in the rest position, abuts against a substantially horizontal surface 27a of the upper portion of the horizontal part of the slot . These two surfaces act on each other and serve as locking surfaces . When the locking boss leaves the horizontal part of the L-shaped slot, the locking surfaces 26a, 27a slides against each other. The force which has to be overcome is the frictional force between the locking surfaces. Since the frictional force is small, it is possible to actuate flushing by applying a small amount of force. Since the float 17 constantly tends to rise, the float, the float rod 21 and thus the locking boss arranged on the float rod rise as soon as the locking boss enters the vertical part of the slot. As a result, the bottom valve 8 opens since the float also lifts up the valve body 13. The float has such buoyancy that is remains in the uppermost position, i.e. the locking boss is situated in the uppermost part of the slot 31, until the set amount of flushing water has drained off . Thus the valve remains open without any need for additional means to keep it in the open position. When the flushing water has drained off, gravity pulls down the float. This quick lowering makes the rocker arm pivot back to the rest position, the locking boss being once again located in the horizontal part of the slot 31. In the embodiment according to Figs 3-5, the pivoting of the rocker arm 28 makes the abutment member 33 pivot away to the left-hand side in Fig. 4 and disengage from the locking boss 32. The upper side of the locking boss 32 has a substantially horizontal surface 32a which, in the rest position, abuts against a substantially horizontal surface 33a of the lower portion of the abutment member. These two surfaces act on each other and serve as locking surfaces. When the locking boss 32 leaves the abutment member 33, the locking surfaces 32a, 33a slides against each other. The force which has to be overcome is the frictional force between the locking surfaces. Since the frictional force is small, it is possible to actuate flushing by applying a small amount of force. The float rod is allowed to rise until it hits a stopping member 34 on the rocker arm. As soon as the abutment member and the locking boss are disengaged, the bottom valve 8 opens by the float also lifting up the valve body 13. As shown in Fig. 5, the upper end of the float rod will return the rocker arm 28 to the initial position when the upper end of the float rod abuts against the stopping member. When the set amount of flushing water has drained off, gravity pulls down the float. Thus the valve remains open without the need for any additional means to keep the same in the open position. The upper side of the abutment member 33 has a sloping or inclined surface 33b, against which the locking boss slides while the float rod is sinking. When the float rod has reached its lowermost position, the inclined surface passes into the horizontal abutment surface 33a, the locking boss snapping back into the rest position. In the embodiment according to Figs 7a-7b, the pivoting of the rocker arm 28 makes the locking boss 26 leave the substantially horizontal part of the L-shaped slot and enter the substantially vertical part of the L- shaped slot. The underside of the locking boss 26 has a substantially horizontal surface 26a which, in the rest position, abuts against a substantially horizontal surface 27a of the lower portion of the horizontal part of the slot . These two surfaces act on each other and serve as locking surfaces . When the locking boss leaves the horizontal part of the L-shaped slot, the locking surfaces 26a, 27a slide against each other. The force which has to be overcome is the frictional force between the locking surfaces. Since the frictional force is small, it is possible to actuate flushing by applying a small amount of force. Since also in this embodiment the float 17 constantly tends to rise, the float, the float rod 21 and thus the locking latch 27 arranged on the float rod will move upwards as soon as the locking boss enters the vertical part of the slot. As a result, the bottom valve 8 opens since the float also pulls up the valve body 13. The float rod is allowed to rise until it hits a stopping member 34 on the rocker arm. The upper end of the float rod returns the rocker arm 28 to the initial position when it hits the stopping member. The float has such buoyancy so as to remain in the uppermost position, i.e. the locking boss 26 is located in the lowermost portion of the slot 31, until the set amount of flushing water has drained off. Thus the valve remains open without the need for any additional means to keep the same in the open position. When the flushing water has drained off, gravity pulls down the float, the locking boss once again being located in the horizontal part of the slot 31. The device according to the invention is very well suited for use in electronic actuation of the flushing. Since only a small amount of force is required to actuate flushing, the current consumption will be low, which is advantageous for the service life of the battery in battery operation. The invention can, however, also be used for mains connection. In particular in public facilities, it is often desirable that the actuation of the flushing should be of non-contact type. Below, a non-contact embodiment of the invention will be described with reference to Fig. 6. A battery unit 60 is arranged at the upper portion of the cistern 1. A support flange 61 of the battery unit rests on the lid 3 of the cistern, so that the battery unit hangs down into the cistern. The battery unit is attached to the flushing fittings by means of an attachment means in the form of a screw 70. The battery unit has a lid 62 which extends over and completely covers the support flange. As shown in Fig. 6, there is room in the battery unit for batteries 63, printed circuit boards 69 and a means 64 for alternative actuation of the flushing, which will be described in more detail below. It is known to use an IR beam (infrared beam) in non-contact actuation of the flushing. In the embodiment of the invention which is shown in Figss la-lb and 3a-3b, an IR transmitter 65 and an IR receiver 66 are shown. It is also feasible to use other types of transmitters and sensors. When flushing, the IR beam is reflected, for instance, on the user's hand, so that the beam reaches the receiver. As a result, a current is sent through the coil 40 in prior-art manner so that an opposed magnetic field forms, the attractive force of the magnet 42 being reduced. It may be necessary to use the means 64 for alternative actuation of the flushing if the ordinary flush actuation means, for some reason, is out of order. The means for alternative actuation is shown, for instance, in Figs la-lb, 3a-3b and 6 and comprises a bar 67 which, in the rest position, is situated in the battery unit 60. When the means is to be activated, the bar is introduced into a guide bush 68. When the bar is located in the guide bush, its lower end abuts against the second leg 30 of the rocker arm. When a pressure is then exerted on the upper end of the bar, the flushing is actuated. Below, the embodiment of the flushing fittings that is shown in Figs 8-10 will be described. Also in the case of this embodiment, the above-described principles of the function of the device are applicable. The rocker arm 28 of the actuation mechanism 20 has a first and a second leg. The first leg 29 supports the retaining device 25, and the second leg 30 co-operates with the flush actuation means 24. The rocker arm 28 is arranged to pivot on the pin 35 which is anchored to the supporting member of the flushing fittings. In this em- bodiment , the rocker arm also has a third leg 71 which constitutes the means 64 for alternative actuation of the flushing. The first leg 29 and the second leg 30 are arranged on the same side of an imaginary, vertical plane through the pin 35, whereas the third leg 71 is arranged on the other side of this plane. In the embodiment which is shown in Figs 8-10, the locking latch 27 of the retaining device is arranged on the upper end of the float rod 21, whereas the locking boss 26 is arranged on the first leg 29 of the rocker arm. It is also possible to arrange the locking latch 27 of the retaining device on the first leg 29 of the rocker arm, and the locking boss 26 on the upper end of the float rod 21. With reference to Figs 8 and 10, it appears that both the locking boss 26 and the locking latch 27 can be doubled, so that there is a locking boss on each side of the first leg 29 of the rocker arm 28 and two parallel locking latches which extend up from the upper end of the float rod. The object of the doubling is to increase the stability and operational reliability of the device . In the embodiment in Figs 8-10, the locking latch has an L-shaped slot 31 with a substantially horizontal part and a substantially vertical part which is, however, somewhat inclined in relation to the vertical plane, as shown in Figs 9a-c. The locking boss 26 runs in the slot 31, the flushing fittings assuming their rest position, when the locking boss is in the substantially horizontal part of the L-shaped slot, and assuming their flushing position, when the locking boss is in the substantially vertical part of the L-shaped slot. The bottom valve body 13 is also in this embodiment fixedly connected to the float rod 21. The float rod can also in this embodiment be provided with a setting scale according to Fig. Id. In the shown embodiment, the flush actuation means 24 has a coil 40, which is fixedly connected to the supporting member and which has an iron core 41 arranged in the coil and displaceable in the longitudinal direction of the same. In the rest position, which is shown in Fig. 9a, the iron core 41 abuts against the outer end of the second leg 30 of the rocker arm. When flushing, a current pulse is transmitted through the coil 40, which generates a magnetic field which affects the iron coil to be displaced out of the coil towards the outer end of the second leg 30 of the rocker arm. As a result, the rocker arm pivots, as shown in Fig. 9b, so that the retaining device 25 is released, whereupon the float rises. A spring 72 is arranged between the supporting mem- ber and the second leg 30 of the rocker arm. When the rocker arm pivots at the actuation of the flushing, as shown in Fig. 9b, the spring 72 is compressed. When the iron core returns to its rest position, the spring urges the rocker arm back to its rest position, as shown in Fig. 9c. The pivoting of the rocker arm 28 results in the locking boss 26 being displaced to the left in relation to the position in Fig. 9a, thus leaving the substantially horizontal part of the L-shaped slot and entering the substantially vertical part of the L-shaped slot. The lower face of the locking boss 26 has a substantially horizontal surface 26a which, in the rest position, abuts against a substantially horizontal surface 27a of the lower portion of the horizontal part of the slot. These two surfaces act on each other and serve as locking surfaces. Even if the two parts of the L-shaped slot are inclined in relation to the vertical plane and the horizontal plane, respectively, and/or are not absolutely perpendicular to each other, the locking surfaces are substantially horizontal . When the locking boss leaves the horizontal part of L-shaped slot, the locking surfaces 26a, 27a slide against each other. The force that has to be overcome is the frictional force between the locking surfaces and the counter-acting force of the spring. Since the amount of frictional force is small and the spring can be selected to have a small spring constant, the flushing can be actuated by applying a small amount of force. Since also in this embodiment the float 17 constantly tends to rise, the float, the float rod 21 and thus the locking latch 27 arranged on the float rod will move upwards as soon as the locking boss enters the vertical part of the slot. As a result, the bottom valve 8 opens by the float also pulling up the valve body 13. The position of the flushing fittings during flushing is shown in Fig. 9c. The float has such buoyancy so as to remain in the uppermost position, i.e. the locking boss is located in the lowermost part of the slot 31 until the set amount of flushing water has drained off. Thus, the valve remains open without the need for any additional means to keep it in the open position. When the flushing water has drained off, gravity pulls down the float. The locking boss then returns to the horizontal part of the slot 31. Just like in the previously described embodiments, this embodiment is also suitable for use in electronic actuation of the flushing and non-contact actuation of the flushing. Below, an alternative to the construction shown in Fig. 6 will be described with reference to Figs 11-15. As shown in Figs 11-12, an electronic unit 73 is arranged at the upper portion of the cistern 1. Two support flanges 74 of the electronic unit rest on an upper flange 75 of the cistern, so that the electronic unit is situated under the lid 3. The lid is fixed by means of a lid nut 76 which is arranged to clamp the electronic unit and the lid together. The lid nut is transparent to IR light. With reference to Figs 13-15, there is room in the electronic unit for printed circuit boards 69, batteries 63, IR transmitters 65 and IR receivers 66. The electronic unit is connected with the coil 40 by means of a cable 77 and a connection means 78. A flashing diode 79 is arranged in the lid nut 76. The flashing diode indicates with a flash the passing of the signal between the IR transmitter and the IR receiver. It can also indicate with a flash, for instance every three seconds, when the battery voltage is getting low, thus indicating the need for a change of batteries. The means 64 for alternative actuation of the flushing is accessible by removing the electronic unit. To actuate the flushing, a pressure is exerted manually on the third leg 71, the rocker arm pivoting so that the locking boss 26 enters the substantially vertical part of the slot 31. The flushing fittings according to the invention have a simple construction which means that the manufac- turing is simple and cheap and that the flushing fittings are reliable during operation.

Claims: CLAIMS 1. Flushing fittings having a bottom valve body (13), which is fixedly connected to or formed integrally with a float (22), and which is adapted to seal against a valve seat (12) with a sealing area and to be lifted from the valve seat by means of an actuation mechanism (20) , which comprises a flush actuation means (24) , c h a r - a c t e r i s e d in that the float (22) has such a volume that its buoyancy is always greater than the sum of all downwards directed forces acting on the valve body, the float and the means connected with the float due to the masses of the float and the means connected therewith and due to a maximally possible water column which is located above the sealing area of the bottom valve body and acts against the same, that the actuation mechanism (20) has a retaining device (25) , which is arranged to prevent the float (22) , in the rest position of the flushing fittings, from lifting up the bottom valve body (13) from the valve seat (12) and which has two locking surfaces (26a, 27a; 32a, 33a) acting on each other, and that the flush actuation means (24) is arranged to release the retaining device, when flushing, by a relative displacement of the locking surfaces along each other. 2. Flushing fittings as claimed in claim 1, c h a r a c t e r i s e d in that the actuation mechanism (20) has a rocker arm (28) , which has a first (29) and a second (30) leg, the first leg (29) supporting the retaining device (25) and the second leg (30) supporting and/or co-operating with the flush actuation means (24) . 3. Flushing fittings as claimed in claim 1 or 2 , c h a r a c t e r i s e d in that the retaining device (25) comprises a locking boss (26) and a locking latch (27) co-operating with the same. 4. Flushing fittings as claimed in any one of the preceding claims, c h a r a c t e r i s e d in that the bottom valve body (13) is fixedly connected to a float rod (21) which is included in the flush actuation means (24) . 5. Flushing fittings as claimed in claims 3 and 4, c h a r a c t e r i s e d in that the locking latch (27) of the retaining device is arranged on the first leg (29) of the rocker arm, while the locking boss (26) is arranged on the upper end of the float rod (21) . 6. Flushing fittings as claimed in claims 3 and 4, c h a r a c t e r i s e d in that the locking latch (27) of the retaining device is arranged on the upper end of the float rod (21) , while the locking boss (26) is arranged on the first leg (29) of the rocker arm. 7. Flushing fittings as claimed in claim 5 or 6, c h a r a c t e r i s e d in that the locking latch (27) has an L-shaped slot (31) with a substantially horizontal part and a substantially vertical part, in which slot the locking boss (26) runs, the flushing fittings being in their rest position when the locking boss is in the substantially horizontal part of the L-shaped slot and the flushing fittings being in their flushing position when the locking boss is in the substantially vertical part of the L-shaped slot. 8. Flushing fittings as claimed in claim 1 or 2 , c h a r a c t e r i s e d in that the retaining device (25) comprises a locking boss (32) and an abutment member (33) co-operating with the same, that the bottom valve body (13) is fixedly connected to a float rod (21) , that the locking boss (32) is arranged on the upper end of the float rod, and that the abutment member (33) is arranged on the first leg (29) of the rocker arm. 9. Flushing fittings as claimed in any one of claims 2-8, c h a r a c t e r i s e d in that the flush actua- tion means (24) has a coil (40), which is fixedly connected to a supporting member (18) and which has an iron core (41) , and a magnet (42) arranged on the second leg (30) of the rocker arm. 10. Flushing fittings as claimed in any one of the preceding claims, c h a r a c t e r i s e d in that electronic means (65, 66) are arranged for activating the flush actuation means (24) . 11. Flushing fittings as claimed in claim 10, c h a r a c t e r i s e d in that the electronic means comprise a transmitter (65) and a receiver (66) . 12. Flushing fittings as claimed in claim 10, c h a r a c t e r i s e d in that the electronic means are an IR transmitter (65) and an IR receiver (66) .

Inventors: ALBERTSEN ERIK H, LINDSTROEM PAUL, ALBERTSEN, ERIK, H., LINDSTROEM, PAUL
Applicants: ALBERTSEN ERIK H, IFOE SANITAER AB, LINDSTROEM PAUL, ALBERTSEN, ERIK, H., LINDSTROEM, PAUL
Application year: 2000
Main classification: E03D1
IPC codes: E03D5, F16K31