The invention relates to an electronically controlled in-wall WC flush valve unit having a flusher
housing and having a hydraulic self-closing valve disposed in the flusher housing and having a wall
cover in which an emergency switch is disposed.
Valve units of the kind mentioned at the beginning are known in many different forms. Normally
such valve units are equipped with sensors that enable the valve units to be operated contactlessly.
Flushing of the WC is actuated either by bringing the hand close to die sensor or automatically by
means of a room monitoring system. Used to actuate these electronically controlled valve units are
either solenoid valves or hydraulic self-closing valves in combination with a magnetic servo valve.
Where solenoid valves are used, it has proved to be disadvantageous that because of their
construction they take up a relatively large amount of fitting space. Moreover, solenoid valves
usually have a connection geometry that is compatible with mechanical flushers. However, this is
relatively expensive. Although hydraulic self-closing valves are smaller than solenoid valves,
magnetic self-closing valves are more complicated to fit. Moreover, in the case of known valve
units the self-closing valve is fitted in a vertical position, as a result of which the replacement of
individual components of the flusher - for example, demounting of the flusher housing - and
mechanical actuation, which is done with the aid of a lever, a slide or pneumatically, is expensive.
In the case of electronically contactlessly controlled in-wall WC flush valve units a manual
emergency actuation means that enables emergency flushing in the event of a power failure can be
provided for in addition to the actuator. Emergency actuation is normally done by means of a
manual switch which is integrated into the front plate or extends through the front plate. In
combination with a solenoid valve this switch enables flushing to be done by means of a battery.
Since batteries are known to have limited service life, the functionality of the emergency switch
requires additional maintenance costs. In the case of hydraulic self-closing valves the switch
actuates the self-closing valve direct with the aid of a mechanical means such as a lever or a slide
system of the kind used in mechanical in-wall WC flush valve units. Also known are pneumatic
means for actuating the valve. Common to all solutions is the complicated fitting of the individual
components, which incurs additional costs.
In contrast to electronically controlled in-wall WC flush valve units mechanical in-wall WC flush
valve units are fitted in a horizontal position. Such mechanical flushers are actuated direct via a

push-switch disposed in a front plate. The flushers are also fitted with a hydraulic cartridge that can
be fitted at the front without having to remove the flusher housing.
The operation of the known self-closing cartridges for mechanical flush valves is shown below in
Figure 11, which represents the state of the art and which shows a cartridge in cross-section, partly
in the open and partly in the closed position. In the closed position shown in the upper half the
cartridge b is disposed in a flusher housing a in the resting condition. Via inlet hole I both piston
chamber e and valve chamber f are under mains pressure. Chambers e and f are separated from each
other by a piston b and connected to each other via a nozzle hole k. Since the pressure-generating
piston surface of piston chamber e is larger than the piston surface of valve chamber f, valve seat g
is closed in this position. If the end of valve spindle c which projects from the cartridge is pressed,
servo valve h is opened, causing the pressure in piston chamber e to drop, in turn causing piston
chamber e to be emptied via a relief hole 1 and a spindle hole j. The end of spindle hole j is located
in the pressureless valve seat hole m and outlet hole n disposed downstream of valve seat g. The
pressure still acting in valve chamber f causes the piston to move up and open valve seat g. Release
of pressure on valve spindle c causes servo valve h to return to its closed position, causing piston
chamber e to be slowly refilled via nozzle hole k from valve chamber f, which is still under
pressure. When piston chamber e is completely filled, valve seat g is once more closed.
Against the background of the above-described state of the art the invention is based on the problem
of creating an electronically controlled in-wall WC flush valve unit with a hydraulic self-closing
valve that is fitted in a horizontal position and provides for the connection of a servo solenoid valve.
The purpose of the invention is also to create an emergency switch that does not require any
additional mechanical or pneumatic means to actuate flushing. According to the invention this
purpose is fulfilled by the features described in claim 1 and claim 5.
The invention enables an electronically controlled in-wall WC flush valve unit with a hydraulic
self-closing valve that enables fitting in a horizontal position to be created. By this means
replacement of the flusher components can be made easy and low-cost. Furthermore, the valve unit
to actuate flushing in accordance with the invention does not need any additional mechanical or
pneumatic means.
Further developments and embodiments of the invention are described in the remaining sub-claims.
An example embodiment of the invention is shown in the drawing and described below in detail.
Shown are in:
Fig. 1 a perspective view of a wall cover for an in-wall WC flush valve unit;
Fig. 2 a section along line A-A in Figure 1;

Fig. 3 a section through a bypass valve;
Fig. 4 a view of a spindle;
Fig. 5 a section through the WC flusher provided for in the valve unit;
Fig. 6 a perspective view of the arrangement of a bypass valve, servo solenoid valve and
self-closing valve;
Fig. 7 a perspective view of a wall cover for an in-wall WC flush valve unit in another
embodiment.
Fig. 8 a section along line B-B in Figure 7;
Fig. 9 a section through the WC flusher provided for in the valve unit;
Fig. 10 a perspective view of the arrangement of a servo solenoid valve with a self-
closing valve;
Fig. 11 a section through the cartridge of a mechanical self-closing valve in accordance
with the state of the art.
The electronically controlled in-wall WC flush valve unit selected as an example embodiment
incorporates a wall cover 1, 101, in which is disposed an emergency switch 2, 102. In the example
embodiment shown in Figure 1 the switch 2 is arranged off-centre, while in the example
embodiment shown in Figure 7 the switch 102 is arranged in the centre of the wall cover 101. As
well as a servo valve 58, 158, which is connected to a self-closing valve 7, the flush valve unit
consists of a WC flusher 6. In the example embodiment shown in Figures 1 to 6 the flush valve unit
also comprises a bypass valve 3, which is connected to the servo valve 58 and the self-closing valve
7.
The wall cover 1, 101 consists of a wall plate 10, 1 10 in which a sensor window 11, 111 is
provided. Provided for under the wall cover 1, 101 is a wall fixing means 12, 112, which is
enclosed by a seal 13, 113. The wall fixing means 12, 112 is fastened to an in-wall mounting box
17, 117 with the aid of fixing screws 14. The mounting box 17, 117 is provided with a fastening
portion 18 in which an inside screw thread 19 is provided for (Figure 1). Also provided for on the
wall fixing means 12 in the example embodiment shown in Figure 1 is a fixing bracket 15 which
incorporates a through-hole 16 for a spindle 40 of the bypass valve 3.
The switch 2, 102 is connected to the spindle 20, 120, by which the valve unit can be actuated. The
spindle 20, 120 is provided with a stepped portion 21, 121, against which a pressure spring 23, 123
is braced. On its side facing away from die stepped portion 21, 121 the spring 23, 123 is braced
against a bottom surface 29, 129 that forms a constituent part of a fixing nut 28, 128. The fixing nut

28, 128 is screwed onto a threaded element 25, 125 that on its side facing away from the fixing nut
28, 128 is provided with a stepped portion 24, 124 that on its side facing towards the wall plate 10,
110 forms a supporting surface 26, 126. At the same time the stepped portion 21, 121 forms on its
inside a stop surface 22, 122 for the stepped portion 24, 124 of the spindle 20, 120 and at the same
time delimits a stepped hole 27, 127 in which the pressure spring 23, 123 and the stepped portion
21, 121 are moveably disposed.
In the example embodiment shown in Figures 1 to 6 the valve unit is provided with a bypass valve
3. The bypass valve 3 incorporates a valve housing 30, through which a housing hole 31 runs. The
housing hole 31 incorporates a number of steps, which form a valve seat hole 32, a spindle hole 33
and a stepped hole 34. The stepped hole 34 forms the inlet side of the bypass valve 3. Formed at the
point of transition from the housing hole 31 and the valve seat hole 32 is a valve seat 36. Following
the stepped hole 34 is a screw thread 38 which partly projects into the housing hole 31. Provided for
in the area of the valve seat hole 32 and at right angles to the housing hole 31 is an outlet hole 35
that incorporates a tapped hole 39 on its side facing towards the circumference of the bypass valve
3. Furthermore, the bypass valve 3 is on its side facing away from the inlet hole 34 provided with a
tapped hole 37 that serves to fasten the bypass valve 3 to the fixing bracket 15 with the aid of a
fixing screw 50.
In the example embodiment shown in Figures 1 to 6 a spindle 40 is guided in the bypass valve 3
(Figure 4). The spindle 40 is provided with a stepped portion 41 against which rests a valve seal 42.
The spindle 40 is also provided with an annular seal 43 set at a distance from the valve seal 42.
When the spindle 40 is in the fitted condition, the annular seal 43 moves in the area of the spindle
hole 33; in the fitted condition the valve seal 42 and stepped portion 41 move in the area of the
housing hole 31 of the bypass valve 3.
The spindle 40 is enclosed by a pressure spring 44, which at its one end is braced agains the stepped
portion 41. At its other end the pressure spring 44 is braced against a sealing plug 45 in which a
hole 46 is provided to receive the spindle 40. The sealing plug 45 is provided with an external screw
thread which corresponds with the screw thread 38 in the bypass valve 3. Following the screw
thread, the sealing plug 45 is provided with a seal 49 that seals the sealing plug 45 against the
bypass valve 3. The seal 49 lies against a stepped portion 48 which forms the stop for the sealing
plug 45. In the area of the stepped portion 48 the sealing plug 45 is also provided with an inlet hole
47.
The bypass valve 3, the servo valve 58, 158 and the self-closing valve 7 are connected by means of
hose lines 53, 54. Each of the hose lines 53, 54 leads to a connecting adapter 51 that incorporates a

pipe connection 52. The pipe connections 52 are screwed into the hole 35 and hole 47 on the sides
of the bypass valve 3 (Figure 2).
The WC flusher 6 consists of a flusher housing 60, 160 that is provided with an inlet pipe
connection 61, 161 and an outlet pipe connection 63, 163. The inlet pipe connection 61, 161
incorporates an inlet hole 62, 162; the outlet pipe 63, 163 incorporates an outlet hole 64, 164. The
WC flusher 6 incorporates inside it an annular duct 65, 165 to which on the side facing towards the
outlet hole 64, 164 is connected a hole 66, 166 to receive the self-closing valve 7. To fasten the self-
closing valve 7, a fixing nut 67, 167 is screwed into the flusher housing 60, 160 on the side facing
away from the outlet hole 64, 164.
The self-closing valve 7 is designed as a cartridge. It consists of a valve housing 70, 170 that is
provided with an inlet hole 71, 171, which in the fitted condition corresponds with the inlet hole 62,
162 of the WC flusher 6. Formed in the housing 70, 170 is a piston chamber 73, 173 in which a
valve piston 75, 175 is moveably disposed. The valve piston 75, 175 incorporates on the side facing
towards the oudet hole 64, 164 of the WC flusher 6 a sealing lip 76, 176 that functions as a valve
seal. The valve piston 75, 175 also incorporates a sealing lip 77, 177 that serves as a seal for the
piston chamber 73, 173. Disposed in the valve piston 75, 175 between the sealing lip 77, 177 and
the sealing lip 76, 176 is a nozzle hole 78, 178 that forms a connection between piston chamber 73,
173 and a valve chamber 83, 183. The valve piston 75, 175 is provided inside with an annular seal
79, 179 that seals the valve piston 75, 175 against a valve spindle 85, 185 running through the valve
piston. The valve spindle 85, 185 is designed as a hollow spindle.
On the side facing towards the outlet hole 64, 164 the self-closing valve 7 forms a valve seat
housing 80, 180, which is provided with a valve seat 81, 181. The valve seat 81, 181 in the fitted
condition corresponds with the sealing lip 76, 176. Formed in the valve seat housing 80, 180 is a
valve seat hole 82, 182 into which the valve pistons 75, 175 can project, depending upon the
operating condition. On the outside the valve seat housing 80, 180 is sealed against the flusher
housing 60, 160 with the aid of a seal 84, 184.
On the side facing away from the oudet hole 64, 164 the valve housing 70, 170 has the valve
spindle 85, 185 running through it. The valve spindle 85, 185 is provided with a spindle hole 86,
186 running through it and on the outside with a stepped portion 87, 187. With the aid of the
stepped portion the valve spindle 85, 185 is braced against the valve housing 70, 170. Also provided
outside on the valve spindle 85, 185 and at a distance from the stepped portion 87, 187 is a seal 88,
188 with which the spindle is sealed against the valve housing 70, 170. To fasten the valve spindle
85, in the example embodiment shown in Figure 5 a locking ring 89 is disposed outside so that the

valve spindle 85 is fixed immoveably on the valve housing 70 between the stepped portion 87 and
the locking ring 89.
Between the stepped portion 87, 187 and the valve piston 75, 175 the valve spindle 85, 185 is
enclosed by a pressure spring 72, 172, which is braced against the stepped portion 87, 187 on the
one side and the valve piston 75, 175 on the other. Provided for at the free end of the valve spindle
85 in the example embodiment shown in Figure 5 is a connecting adaptor 51 that serves to connect
the line 54 and so to connect to the outlet of the servo solenoid valve 58 and the outlet from the
bypass valve 3, distribution being effected by means of a T-member 55. In the example
embodiment the T-member 55 is manufactured from plastic. The lines 53, 54 are likewise
manufactured from plastic. Other materials, particularly metal, may also be used to make the lines.
Arranged in the valve housing 70, 170 and next to the valve spindle 85, 185 is a spindle 90, 190
which has a spindle hole 92, 192 running through it. The spindle 90, 190 is therefore also designed
as a hollow spindle. At its end facing away from the valve piston 75, 175 the spindle 90, 190
incorporates a stepped portion 91, 191 on which the spindle 90, 190 is braced against the valve
housing 70, 170. The spindle 90, 190 also has a seal 93, 193 running round it to seal the spindle
against the valve housing. Furthermore, provided for on the outside on the end facing towards the
piston 75, 175 is a locking ring 94, 194 to prevent the spindle 90, 190 from being axially displaced
between the stepped portion 91, 191 and the locking ring 94, 194.
Provided for at the free end of the valve spindle 90 in the example embodiment shown in Figure 5 is
a connecting adapter 51 that serves to connect the line 53 and so to connect to the inlet of the servo
solenoid valve 58 and the input side of the bypass valve 3, distribution being effected here likewise
by means of a T-member 55 (Figure 6). Provided for at the free end of the valve spindle 190 in the
example embodiment shown in Figure 9 is a pipe connection 152 that with the aid of a connecting
adapter 151 serves to connect the line 153 and so to connect to the servo solenoid valve 158. To
facilitate assembly and fitting and also maintenance of the valve unit in accordance with the
invention the connecting adapters 51, 151 can also be designed as plug-in couplings and to be
detachable.
Disposed next to the stepped portion 187 in the example embodiment shown in Figures 7 to 10 is a
valve seal 195 that corresponds with a valve seat 196 on the valve housing 170. Furthermore, the
spindle 190 is provided with a relief hole 197 that leads to a valve seat hole 198 in the valve
housing 170 (Figure 9). By this the spindle bore 186 is connected to the piston chamber 173 when
the valve piston 175 is in an open condition.
As can be seen in the example embodiment shown in Figures 1 to 6, the valve spindle 85 is
disposed so as to be axially indisplaceable. As a result of this, in this embodiment the valve unit can

be actuated only by pressing the emergency switch 2, since, unlike in the example embodiment
shown in Figures 7 to 10, the emergency switch acts on the bypass valve 3 and not on the hollow
spindle. In the example embodiment shown in Figures 7 to 10, on the other hand, operating the
emergency switch 102 causes the hollow spindle 185 to move axially and so cause the valve unit to
be actuated. However, the design shown in Figures 7 to 10 makes it necessary to dispose the
emergency switch 102 in the extension of the longitudinal axis of the hollow spindle 185.

Claims
1. Electronically controlled in-wall WC flush valve unit having a flusher housing (60, 160)
and having a hydraulic self-closing valve (7) consisting of a valve housing (70, 170) and
having a wall cover (1, 101) in which is disposed an emergency switch (2, 102),
characterised in that the flusher housing (60, 160) is fitted in a horizontal position and
the self-closing valve (7) is designed as cartridge and incorporates a valve spindle (85,
185) that is provided with a spindle hole (86, 186) running all the way through and in
that disposed in the valve housing (70, 170) is a further spindle (90, 190) that has a
spindle hole (92, 192) running through it and in that provided for at the free end of each
of the valve spindles (85, 90, 185, 190) is a connecting adapter (51, 52, 151, 152) for
connecting lines (53, 54, 153, 154), where the line (53, 153) connects the spindle (90,
190) to the inlet of a servo solenoid valve (58, 158) and the line (54, 154) connects the
spindle (85, 185) to the outlet of the servo solenoid valve (58, 158).
2. WC flush valve unit in accordance with claim 1, characterised in that the lines (53, 153,
54, 154 ) are manufactured from metal.
3. WC flush valve unit in accordance with claim 1 or 2, characterised in that the lines (53,
153, 54, 154) are manufactured from plastic.
4. WC flush valve unit in accordance with any one or more than one of the aforementioned
claims, characterised in that the connecting adapters (51, 52, 151, 152) are plug-in
couplings.
5. Electronically controlled in-wall WC flush valve unit having a flusher housing (60, 160)
and having a hydraulic self-closing valve (7) consisting of a valve housing (70, 170), and
having a wall cover (1, 101) in which is disposed an emergency switch (2, 102),
characterised in that the emergency switch (2, 102) corresponds with a spindle (40) of a
bypass valve (3) or a spindle (185) of the self-closing valve (7) to open a bypass valve
(3) or the self-closing valve (7).
6. WC flush valve unit in accordance with claim 5, characterised in that provided for at the
inlet and outlet of the bypass valve (3) are connecting adapters (51) for the lines (53, 54).

7. WC flush valve unit in accordance with claim 5 or 6, characterised in that the lines (53,
54) are connected with the aid of T pieces (55).
8. WC flush valve unit in accordance with any one or more than one of the aforementioned
claims, characterised in that the bypass valve (3) is connected via its inlet hole (34) to
the inlet of the servo solenoid valve (58) and the spindle (90) of the self-closing valve
(7).
9. WC flush valve unit in accordance with any one or more than one of the aforementioned
claims, characterised in that the bypass valve (3) is connected via its outlet hole (35) to
the outlet of the servo solenoid valve (58) and the spindle (85) of the self-closing valve
(7).
10. WC flush valve unit in accordance with claim 5, characterised in that the self-closing
valve (7) incorporates a valve spindle (185) that is provided with a spindle hole (186)
running all the way through and that in the open condition is connected via a relief hole
(197) and a valve seat hole (198) to a piston chamber (173).