Note: Descriptions are shown in the official language in which they were submitted.
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This invention is concerned with a shower fitting of
the type which is adapted to be connected to supplies of
hot and cold water and which is adapted to provide a
supply of water, the temperature of which may be varied
by varying the proportions in which the hot and cold
water are mixed together, such fittings comprising a
shower head comprising an inlet connection for the inlet
of water and a spray outlet from which water flows in the
form of a spray, and particularly of the kind in which
the shower head is capable of being held in the hand by
the user and moved freely about as is desired. Such a
shower ~itting is hereinafter referred to as being of the
kind specified.
.
A shower fitting of the kind specified may comprise
a generally Y-shaped conduit, two branches of which
comprise end portions which are adapted to be secured to
hot and cold water taps, and the third branch comprising
an end portion which is secured to the shower head, which
may be used remote from the taps, the hot and cold water
mixing together in the third branch of the conduit as it
flows towards and into the shower head.
.
One of the difficulties encountered in shower
fittings of this kind is that there is often difficulty
in exercising control over the temperature of the water
flowing through the outlet by virtue of the distance
which there may be between the taps and the user, and by
virtue of the time delay in response to such exercise of
control by the quantity of water in the conduit.
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Another of the difficulties which is encountered is
when it is desired to shut off the water flowing from the
shower head, and this must be effected by turning off the
taps, which may be remote from the user.
Another shower fitting of the kind specified
comprises a fixed mixing unit, which may be secured to a
wall of a shower cubicle, to which supplies of hot and
cold water are delivered, and a sinele flexible conduit
extending from the mixin~ unit to the inlet connection of
the shower head, the mixing unit conprising valve neans
which may be operated manually to vary the proportions in
which the hot and cold wate-r are mixed to flow along the
conduit towards the shower head. The valve means may
comprise a single operating member, which may be thermo-
statically controlled, or may co~nprise separate taps for
controlling the rate of flow of hot and cold water to the
mixing unit. Such types of shower fitting may comprise a
fixed mounting bracket secured to the wall of the shower
cubicle on which the shower head may be releasably
mounted so that the shower head can be used alternatively
in this position or in a position removed from the
mounting bracket.
Shower fittings of this kind suffer not only from
the difficulties set out above, but also from the
difficulty that the mixing unit projects out into the
area of the shower cublicle where i~ can prove an awkward
obstacle for tne user of the shower. ~tte:~pts to over-
come this proble:n have ,nvolved the provision ~of a
suitable recess in the wall of thc shower cubicle, so
that the whole of the mixing Ullit and the valve means can
be accommodated in such recess but this considerably
increases the overall costs of the shower installation.
.
It has also been proposed to position the mixing
unit and the valve means outside the shower cubicle, such
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as on the remote side of a shower curtain, but this makes
the control difficult for the user to reach.
Further, where the hot water is mixed with cold
water from a public mains supply, and where it is
required that there be positive means for isolating one
supply from the other when the shower is not in use, this
requires the provision of a positive shut-off valve means
: in the mixing valve itself. This latter expedient is
difficult to acco.nplish in practice, because when the
shower head is in its static position, mounted on the
mounting bracket, there may be a static head in the order
of about four feet of water remaining in the conduit
between the valve and the shower head, and this head of
water can cause leakage past the shut-off valve.
1~ A further type of shower, fitting is known as the
instantaneous type, and comprises a heating chamber an
inlet of which is connected to a cold water mains supply,
and an outlet of which is connected to a shower head.
The heating element in the heati`ng chamber may be
designed to operate under constant heat input, t`ne
temperature of the water flowing from the shower head
being controlled by a valve neans which controls the rate
of flow o~ water through the heating charnber between a
lower rate, corresponding to a safe maximum tenperature,
and a higher rate. The heating chamber would addition-
ally co;npr`~ise a safety device operative to switch off the
heating eiement in the event of an unsafe high
terr.perature being reached by the water flowing ther~e-
~: through.
However such shower fittings suffer from the dis-
advantage that the flow rate may vary with variation in
water pressure, such as may be caused by another person
in the premises turning on a mains water tap and such
variations in flow rate wlll produce changes in the
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temperature of the water flowing from the shower head,
which may be uncomfortable and/or inconvenient.
It is one of the various objects of the invention to
provide an impro~ed form of shower fitting which reduces
the difficulties set out above.
According to this invention there is provided, in or
for a shower fitting of the type which is adapted to be
connected to supplies of hok and cold water and which is
adapted to provide a supply of water, the temperature of
which may be varied by varying the proportions in which
the hot and cold water are mixed together, the fitting
comprising a shower head comprising inlet connection
means for the inlet of water and a spray outlet through
. which water flows from the shower head, the improvement
wherein the shower head comprises a body which is formed
internally to provide a mixing chamber, inlet connection
means being provided on the body to which separate
supplies of hot and cold water may be connected, such
supplies of water flowing into the chamber wherein said
supplies are mixed, the proportions in which the hot and
cold water flow into the mixing chamber, and hence the
temperature of the water flowing from the outlet, being
- controlled by valve means mounted on the body of the
shower head.
Said valve means may be wholly manually operated or
it may be thermostatically controlled and preferably
includes a temperature responsive device which is under
the influence of the temperature of the water mixture and
which operates a movable valve member ko control the
~ proportions of hot and cold water entering the mixing
chamber .
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Preferably the body is of elongate form, the movable
valve member being arranged for sliding movement te.g.
linear or rotary) in the body and may conveniently be in
the form of a flat plate or ported disc provided with
control ports and having sliding engagement with a flat
face or faces of a valve block which has supply ports
therein connected to the inlets for the hot water and
cold water.
With a shower head according to the present
invention, when in the static position, there is very
little head of water in the mixing chamber (possibly 2
inches or less) and thus ~ore favourable conditions for a
positive shut-off valve to function satisfactorily.
... ..
Thus preferably the valve means is also operative to
provide for complete shut-off of water flowing into the
mixing cham~er.
FIGURE 1 is a perspective view showing the exterior
shape of one form of a shower head which is a preferred
embodiment of this invention and which has been selected
for the purposes of illustrating the invention by way of
example;
FIGURES~2 and 3 are fragmentary views showing alter-
native positions for the actual spray head;
FIGURE 4 is a view in side elevation showing the
interior mechanism including thermostatic control and
positive shut-off means;
~ FIGURES 4a, 4b and 4c are diagrammatic views showing
j different positions of the valve control plate;
FIGURE 5 is a detail view to illustrate the position
where the wedge plate is in the fully shut-off position;
FIGURE 6 is a detail view of the-inlet manifold;
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FIGURE 7 is a top plan view on Figure 6;
FIGURE 8 is a bottom plan view on Figure 6; and
FIGURE 9 is a detail plan view of the valve block,
looking from above in Figure 4;
FIGURE 10 is a fragmentary view showing additional
details of the valve construction;
FIG~E 10a is a fragmentary perspective view of the
face of the valve body.
Referring to Figure 1, the body 10 of the shower
head is of generally elongated form and o~ such external
dimensions as to enable the user to easily hold it in the
hand and in the form shown in Figure 1, the actual spray
head is indicated at 11 at the one end of the body with
-- the direction of the outcoming spray indicated by the
arrow. A manual control knob 12 is positioned adjacent
the spray head 11 and the inlet manifold 13 is positioned
adjacent the opposite end of the body with a common inlet
conduit 14 by which separate supplies of hot and cold
water may be connected to the manifold 13.
In the alternative arrangement of Figure 2, the
manual control knob 12 is combined with the spray head 11
at the one end of the body and in another possible
arrangement shown in Figure 3, the spray head ll`is
arranged adjacent the end of the body with the manual
control knob 12 positioned at the extreme end of the
body.
Referring now to Figures 4 to 9, the outlire of the
body 10 is indicated by the chain dotted lines in Figure
4, which view is arranged so that the shower head is
shown in an upright and inverted position, the inlet
manifold 13 being at the top and the manual control knob
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12 and spray head 11 (not shown in Figure 4) being at the
bottom. The inlet manifold 13 comprises two concentric
tubes, there being an outer tube 15 and an inner tube 16,
with an annular space 17 between these two tubes. The
flexible conduit 14 which conveys the hot and cold water
from the supplies to the shower head is also of con-
centric construction, having an outer tube and an inner
tube with an annular space therebetween so that one fluid
can flow along the annular space and the other fluid
along the inner tube. In the examplè shown, the cold
water supply is connected to the outer tube so that cold
water flows through the annular space and eventually
through the annular space 17 of the manifold and hot
water flows through the inner tube and eventually through
the central tubular portion 18 of the manifold.
However, if desired separate connection means for
the hot and cold water supplioes rnay be provided on the
body, to which separate conduits are connected.
The manifold 13 may be formed integrally with the
body 10 (e.g. as a moulding in ?las~i~/s ~aterial) or it
may be a separate part which is ifitted to thc body.
Within the body the ~.anifoid has a part 19 of square form
and in the case where the r.aniIold is~ formed separately
fron tne body, a suitable sealin~ gasket 20, as shown in
Figure 9, would be provided between the part 19 and the
opening in the wall of the body 10. As shown in Figure 7,
the part 19 of the ~ani~old is formed with two col~ water
passages 21 exter;din~ there'hrou3h and colq~u~.icating
with the cold water space 17 and a colnmon~'hot water
passage 22 colnmunicating via a central pas~sage in the
part 19 with the central hot water inlet 1~.
. . . .
The mixing valve body 23 is secured to the part 19
of the inlet manifold by the usc of a number of screws,
one of which is shown at 24 in Figure 9, and the valve
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body 23 has four separate ports extending therethrough,
two of which cornmunicate with the cold water passages 21
in the part 19 of the manifold and the other two of which
communicate with the common ho~ water passage 22 in the
part 19. Such ports are indicated at 25 in Figure 4 and
Figure 9, and in the diagrammatic view of Figures 4a to
4c, the ports are designated by the letter C which
indicate cold water ports and H to indicate hot water
ports.
A valve control plate 26, which is of flat form 9 iS
mounted within the valve body 23 in sliding engagement
with the flat face of the valve block to which the ports
25 extend, and as shown in Figures 4a to 4c, the valve
control plate 26 is provided with four apertures each of
square form and arranged in two pairs, there being two
apertures 27 for co-operation with the hot water ports 25
in the valve block and two apertures 28 for co-operation
with the cold water ports 25 in the valve block.
Near its one end, the valve control plate 26 has an
aperture 29 throu~h which projects a pe~ 30 connected to
the one end of the body of a temperature responsive
ther;nostat device generally indicated at 31, and at its
opposite end the body of the thermostat 31 has an abut-
mcnt platc 32 which bears aeainst the pcriphery of a cam
co.nprising a circular disc 33 mounted eccentrically about
an axis of rotation 34, with the manual control knob 12
being connected to the cam 33 and also rotatable about
the axis 34. The body of the tner;nostat 31 is ur~ed
resiliently into contact with the periphery of the cam 33
by means of a coil sprine 35 eneaeing the abutment plate
32 at one end and engaging a fixed abutment (not shown)
within the body 10 at its other end. The temperature
responsive thermostat device 31 may be of eenerally known
form such as a wax~filled capsule or bellows, or known
fol~n of linear bimetallic device ilaving the character-
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istic that increase in temperature results in correspond-
ing increase in the effective overall length of the
device 31, there being a corresponding contraction in
overal effective length upon decrease in temperature.
Such temperature responsive devices are well known and
further description is not considered necessary.
The valve block 23 is completed by a cover plate 36
secured to the projecting sides of the valve block by the
screhs 24 so as to leave a space between the inside face
of the cover plate 36 and the valve control plate 26,
such space being of rectangular cross-sectional area and
having fitted therein a wedge plate 37 which has one flat
face in sliding engagement with the one face of the valve
control plate 26 and has its tapered face in engagement
with a correspondingly tapered face formed on the inside
of the cover plate 36. At its larger cross-section end,
the wedge plate 37 has connected thereto a coil spring 38
which at its other end is connected to a fixed me~ber
within the body 10 so that the wedge ?late 37 is urged
resiliently in the direction towards the axis 34 of can
. 33, which is the downwards direction as seen in Figure 4.
At its end remote from the spring 3~, the wedge
plate 37 has a.. elongated slot 39 extending in the
direction of its length and engaging over the projecting
peg 30.
From the above it will be aDpreciated that the hot
water and cold water entering via the manifold 13 passes
- through the passages 21 and 22 in the rnanifold and then
through the separate hot water and cold water ports 25 in
the valve block 23 and then into the interior of the body
10 when the valve control plate 26 is in a partially open
or fully open position where the hot water mixes with the
cold water to provide a warm or hot water rnixture which
exits through the spray head 11. In the position of the
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part shown in Figure 4, the valve control plate 26 is in
the position of Figure 4a so that the valve is in the
fully shut-off position.
To operate the mixing valve of the shower head from
this fully shut-off position, the manual control knob 12
is turned so as to rotate the cam 33 and allow the spring
35 to urge the thermostat device 31 in the downwards
direction as seen in Figure 4, so as to move the valve
control plate 26 from the fully shut-off position of
Figure 4a to a first intermediate position as shown in
Figure 4b in which the two ports 28 in the valve control
plate are in full register with the two cold water ports
in the ~alve block, with the hot water ports 27 of the
control plate being out of register with their corres-
ponding hot water ports in the valve bloc'~ so that a
supply of cold water is obtained from the spray head.
Further movement of the manual control knob in the same
direction wil~ bring the valve control plate 26 to the-
fully open position shown in Figure 4c where only the hot
water ports 27 are in register with their corresponding
ports in the valve bloc~, the cold water ports being out
of register so that a supply of hot water at maximum
te,nperature is available,
In use, a position somewhat between Fi~ure 4b and 4c
can be selected to provide a discharge of warm water at a
desired temperature and having reached such selected
position, the posi~ion of the valve plate 26 in relatlon
to the valve block 23 is maintained by the thermostat
device 31 which moves in the appropri,ate direction to
3o alter the position of the valve control plate 26 in
response to any increase or decrease in te~nperature of
the water mixture.
1:
It will be appreciated that once the manual control
is operated to move the valve plate 26 from the fully
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closed position of Figure 4a, the pressure exerted by the
wedge plate 37 is reduced and there is only a minimurn
arnount of frictional resistance to movement of the plate
26 over the range from fully closed to fully open. Such
frictional resistance to movement can be further reduced
by the choice of suitable materials for the valve block
23, valve control plate 26 and wedge plate 37.
As seen in Figure 5, the wedge plate 37 has project-
ing shoulders 40 ~hich are for the purpose of limiting
the travel of the wedge plate 37 from the fully shut-off
position (Figures 4 and 4a). During the opening`opera-
tion of the valve when the wedge plate reaches the
position corres?onding to Figure 4b, the shoulders 14
engage the valve block 23 to prevent a further rnovement
of the wedge plate and then in between the position of
~` Figures 4b and 4c the peg 30 can move freely in the slot
39 of the wedge plate until thè manual control knob is
again operated to shut off the valve when the peg 30
engages the end of the slot 39 and positively moves the
~o valve plate 20 and wedge plate 37 towards the shut-off
position, and also ensures the ?ositive wedging action of
tiie wed~e plate 37 to firmly press the valve control
plate 26 into sealing en6agement with the cooperating
~; face of the valve block 23.
The requirenent for a positive shut-off and isola-
tion Or the hot anà cold water sup~lies is thus satisfied
and, as e~?lained hereinbefore, as there is only arninute
head of static water likely to re~.ain in the body 10 when
it is in its static position there is unlikely to be any
leakage through the valve of such re;naining water. Such
possibility can be further reduced by providing a pin
hole at the underside of the body 10 as shown in Figure 1
to allow any such rernaining water to drain away. During
operation such pin hole would be covered by the hand of
the user and no water would escape therefrorn. An
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alternative arrangement would be to have a valve (e.g. a
ball valve) opening in the position where a head of ~later
could exist 9 i.e. ~ravity operated.
The spring 38 acting on the wedge plate 37 ensures
that when the mixing valve is operating the wedge plate
will be moved to the position corresponding to Figure 4b
where it is arrested by engagement of the shoulders ~0
and is thus always, during operation, in the position
which offers minimum of frictional resistance ko movement
of the valve control plate 26.
Referring now to Figure 10, there is shown there a
preferred practical feature of the construction of the
valve in the form of a pad 42 of resilient material
interposed between the heads of the securing screws and
the plate 41 having the inclined surface which is
opposite the wedge plate 37. An outer cover plate 43 is
provided beneath the heads of the screws and the presence
of the resilient pad 42 ensures that when the valve is
assembled a known force is exerted througl1 the wedge
plate 37 upon the valve control plate 26. This arrange~
ment also provides co~.npensation for wear without changin~
the linear relationship of the slidins parts.
In practice it may be found difficult to ensure that
tnere is a perfec'ly flat surface on the ported face of
the valve blocl; 23 whlch ls engaged by the control plate
26 and to overcome this problen the construction shown in
Figures 10 and 10a may bc used wherein ~he port opcnings
are constituted by locally raised collars 25a, the outer
faces of which can be forme~ accurately in a common plane
; 30 and thus the flatness of the remainir.g area of this face
of the valve block is not critical. Instead of collars
raised frorn the face of the valve block, "0" rings could
; be used, inserted in said face.
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.~
In order to ensure that the pressure exerted on the
collars 25a by the control plate 26 is evenly distributed
over all four, the inclined face of the top plate 41 ,nay
have a part-spherical projection 44 which engages the
wedge plate 37, the projection 44 being positioned so
that its point of engagement with the wedge plate 37 is
centrally located equidistant from the axial centre lines
of all four collars 25a.
In an alternative arrangement ~he control Or opera-
tion of the wedge plate may be separated from that of the
control plate 26 by providing a second cam, on the same
shaft as the cam 33, to control the wedge plate; this
~ill allow for designing independent cam dwells as
required.
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l~ The shower head above described may be used in a
shower fitting of the type comprising flexible conduit,
which may be co-axial (as described above), or may
comprise twin hose connected at one end to the inlet
manifold, and at the other end to separate hot and cold
water outlets. Such outlets may be provided by fixed
conduits provided (e.g.)in a shower cubicle there being
also provided a mounting bracket on which the shower head
may be mounted when desired, or may be provided by hot
and cold water taps. Alternatively, such a shower
fitting may be utilised in conjunction with a supple-
mentary outlet of the type often provided on baths, a
manual control rnember of which being movable alternately
between a first position in which water is directed
through an outlet into the bath itself, and a second
3o position in which thc watcr is dircctc~ through the
supplementary outlet.
.
In the application of the invention to a shower
fitting of the instantaneous type, it is envisaged that
the flexible conduit will be connected at one end to the
7 ~ 5
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inlet manifold, and at the other end to the outlet of the
heating chamber on the one hand, and to an additional
cold water supply on the other hand. Such additional
cold water supply may conveniently be provided by a by-
pass duct, conveniently being taken off adjacent to the
inlet of the heating chamber. The valve means of the
shower head may thus operate to monitor the temperature
of the water flowing from the spray outlet thereof and in
the event of a sudden rise in the temperature of the hot
waterflowing from the heating chamber to the shower head,
the valve means will be operative to increase the rate at
which cold water is admitted to the mixing chamber,
and~or to decrease the rate at which hot water is
admitted to the mixing chamber, to stabilise the
temperature of the water flowing from the shower head to
1 the desired temperature.
,
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