SHOWER HEAD
The present invention relates to spray heads for producing a spray of fluid and may have
particular application to a shower head.
Background to the Invention
Shower heads of the prior art are typically provided with a plurality of apertures from which a
stream of water issues. A problem with such shower heads of the prior art is that they often do
not provide a satisfactory spray when used at low flow rates.
The applicant has discovered that many users prefer the sensation of much smaller droplets of
water than are created by the shower heads of the prior art. The applicant’s International
Publication No. WO2004/101163 describes a shower head which has groups of two or more
nozzles which are arranged such that jets of water issuing from the nozzles collide and break
into smaller droplets. This arrangement works well, and is particularly advantageous when used
at low flow rates.
Another method used by the prior art to create smaller droplets is to direct the stream of water
from each nozzle onto a surface of the shower head so that it breaks up into relatively small
droplets. However, a problem with many prior art shower heads of this type is that they either
provide a spray pattern which is too small, or one which has a central area which has little or no
coverage.
Object
It is an object of the present invention to provide a spray head and/or a showerhead which will
overcome or ameliorate problems with such spray heads/showerheads at present, or which will
at least provide a useful choice.
Brief Summary of the Invention
According to one aspect of the present invention there is provided a shower head comprising an
inlet in fluid communication with a plurality of nozzles, the shower head further comprising a
plurality of impingement surface portions, each of the nozzles adapted to produce, in use, a jet
of fluid which is directed toward a respective impingement surface portion, the arrangement
being such that each jet of fluid impacts on the respective impingement surface portion, flows to
an edge of the respective impingement surface portion, and breaks into a stream of droplets,
each stream of droplets having an elongate transverse cross-section.
Preferably the angle between the jet of fluid and the respective impingement surface portion is
between 10 degrees and 40 degrees.
Preferably the jet of fluid impacts on the impingement surface portion between 1mm and 14mm
from an edge of the impingement surface portion.
Preferably each stream of droplets travels through an aperture in the spray head.
Preferably the streams of droplets are substantially unimpeded by the aperture.
Preferably the aperture comprises a slot.
Preferably the aperture has a width of substantially 3mm or less.
Preferably the elongate transverse cross section of each stream of droplets has a longitudinal
axis, and the longitudinal axes of at least two of the streams of droplets are substantially parallel
to each other.
Preferably the longitudinal axes of each said stream of droplets are substantially parallel.
Preferably each said stream of droplets has a geometric centreline, and the geometric
centrelines of at least two of the streams of droplets are substantially parallel to each other.
Preferably each said stream of droplets has a geometric centreline, and the geometric
centrelines of at least two of the streams of droplets are substantially divergent.
Preferably a plurality of said impingement surface portions form part of a single impingement
surface.
Preferably each said impingement surface portion is part of a single impingement surface.
Preferably the spray head comprises a first set of a plurality of nozzles and a second set of a
plurality of nozzles, each nozzle in the first set of nozzles directed towards a respective first
impingement surface portion and each nozzle in the second set of nozzles directed towards a
respective second impingement surface portion, wherein, in use, jets of fluid issuing from the
nozzles impact on the respective impingement surface portions and break into a stream of
droplets, wherein the nozzles and impingement surface portions are configured such that the
geometric centrelines of the streams of droplets from the first impingement surface portions
converge, and the geometric centrelines of the streams of droplets from the second
impingement surface portions are non-convergent.
Preferably the geometric centrelines of the streams of droplets from the second impingement
surface portions are substantially parallel.
Preferably the geometric centrelines of the streams of droplets from the second impingement
surface portions are substantially divergent.
Preferably the geometric centrelines of the streams of droplets from the second impingement
surface portions are substantially parallel, and the spray head comprises a third set of a plurality
of nozzles, each nozzle in the third set of nozzles directed towards a respective third
impingement surface portion, wherein, in use, jets of fluid issuing from the third set of nozzles
impact on the respective impingement surface portions and break into a stream of droplets,
wherein the third set of nozzles and impingement surface portions are configured such that the
geometric centrelines of the streams of droplets are substantially divergent.
Preferably the nozzles are arranged along a notional curved line, the nozzles arranged such
that a jet of fluid issuing, in use, from at least some of said nozzles has a direction which
includes a component which is substantially tangential to the notional curved line.
Preferably the nozzles are arranged along a notional curved line, and wherein the elongate
transverse cross section of each stream of droplets has a longitudinal axis, and the longitudinal
axis of each stream of droplets is non-tangential to the notional curved line.
Preferably the notional curved line is substantially elliptical or semi-elliptical.
Preferably the notional curved line is substantially circular or semi-circular.
Preferably the notional curved line is a simple closed curve.
Preferably the spray head comprises an outer housing having an annular portion and a handle
portion.
Preferably the spray head comprises an annular body engaged with the annular portion of the
housing, wherein the nozzles are defined by apertures in the annular body.
Preferably the spray head comprises an impingement surface member engaged with the
annular housing.
Preferably the slot is defined in part by the annular body.
According to a second aspect of the present invention there is provided a shower head
comprising a plurality of spray stream generating formations arranged along a notional curved
line, each spray stream generating formation adapted to produce a stream of droplets in use,
each stream of droplets having an elongate transverse cross-section which has a longitudinal
axis, wherein the longitudinal axis of each said stream of droplets is non-tangential to the
notional curved line.
According to a third aspect of the present invention there is provided a shower head comprising
a plurality of spray stream generating formations arranged along a notional curved line, each
spray stream generating formation adapted to produce a stream of droplets in use, each stream
of droplets having a geometric centreline and an elongate transverse cross-section, wherein a
first portion of the spray streams have convergent geometric centrelines and a second portion of
the spray streams have non-convergent geometric centrelines.
According to a fourth aspect of the present invention there is provided a shower head
comprising a plurality of nozzles, each nozzle adapted to produce, in use, a jet of fluid which is
directed toward a respective impingement surface portion, wherein each jet of fluid impacts on
the impingement surface portion and breaks into a stream of droplets.
According to a further aspect of the present invention there is provided a shower head
substantially as herein described with reference to any one or more of the accompanying
figures.
The invention may also be said broadly to consist in the parts, elements and features referred to
or indicated in the specification of the application, individually or collectively, in any or all
combinations of two or more of said parts, elements or features, and where specific integers are
mentioned herein which have known equivalents in the art to which the invention relates, such
known equivalents are deemed to be incorporated herein as if individually set forth.
Brief Description of the Figures
Figure 1 is a perspective view of a shower head according to one embodiment of the
invention.
Figure 2 is an exploded perspective view of the shower head of Figure 1.
Figure 3 is a side view of the shower head of Figure 1 with a section of the housing
removed to show the annular body.
Figure 4 is an enlarged view of section A of Figure 3, with the shower head in use.
Figure 5 is a schematic view of a stream of droplets from an impingement surface portion.
Figure 6a is a diagrammatic front view of the annular portion of the shower head showing
droplet streams issuing from one embodiment of the present invention.
Figure 6b is a diagrammatic side view of the embodiment shown in Figure 6a showing the
geometric centres of the streams of droplets generated.
Figure 7a is a diagrammatic front view of the annular portion of the shower head of another
embodiment of the present invention, showing the droplet streams issuing from
one impingement surface portion, the other droplets streams having been omitted
for clarity.
Figure 7b is a diagrammatic side view of the embodiment shown in Figure 7b showing the
stream of droplets.
Figure 8a is a diagrammatic perspective view of an alternative version of the embodiment
shown in Figure 7a and 7b, with the droplet streams represented
diagrammatically as flat “fans”.
Figure 8b is a diagrammatic front view of the version shown in Figure 8a.
Figure 9 is a diagrammatic perspective view of a further embodiment of the invention, with
the droplet streams represented diagrammatically as flat “fans”.
Figure 10 is a diagrammatic perspective view of another embodiment of the invention, with
the droplet streams represented diagrammatically as flat “fans”.
Figure 11 is a diagrammatic perspective view of a still further embodiment of the invention,
with the droplet streams represented diagrammatically as flat “fans”.
Figure 12 is a top perspective view of an alternative embodiment of the shower head shown
in Figures 1 to 4.
Figure 13 is a perspective view from beneath of the shower head shown in Figure 12.
Figure 14 is an exploded perspective view of the shower head shown in Figure 12.
Figure 15 is a cross-section side view of the shower head shown in Figure 12.
Figure 16a is a diagrammatic perspective view of a jet of water directed at an impingement
surface portion having a concave profile.
Figure 16b is a diagrammatic perspective view of a jet of water directed at an impingement
surface portion having a convex profile.
Figure 16c is a diagrammatic perspective view of a jet of water directed at an impingement
surface portion having an undulating profile.
Figure 17 is a diagrammatic longitudinal cross-section view of a curved impingement
surface portion.
Figure 18 is a further enlarged view of the area A of Figure 4.
Best Modes for Performing the Invention
Referring first to Figures 1, 2, 3 and 4, a spray head which is adapted for use as a shower head
according to one embodiment of the present invention is generally referenced by arrow 100. In
the embodiment shown the shower head comprises an outer housing 1. The housing 1 has a
handle portion 2 provided which defines an internal conduit 3. The conduit 3 has an inlet 4 and
an outlet 5.
The housing has an annular portion 6 inside which an annular body 7 is engaged. The radially
outer surface 9 of the body 7 is provided with an annular groove 10. Sealing means, typically
O-ring seals 11, may be provided on either side of the annular groove 10. Alternatively the
annular body may be fixed to the housing in a watertight manner through the use of a suitable
adhesive or welding technique.
A plurality of apertures 12 extend from a wall 13 of the annular groove 10 to a radially extending
wall 14 of the annular body 7. The apertures 12 define nozzles 15 (best seen in Figure 4) for
creating jets of fluid 16 when the annular groove 10 is supplied with pressurised fluid.
In a preferred embodiment a spray head which has been optimised to provide a 9 litre/minute
total flow rate may be provided with between 10 and 20 apertures 12, more preferably around
apertures. The apertures 12 have a diameter between 0.8mm and 2mm if circular, although
other dimensions providing substantially the same cross-sectional area may be used if non-
circular apertures are used. In some embodiments the apertures may be elongate slits, for
example curved elongate slits. Spray heads which are designed to provide greater overall flow
rates may have an increased number of apertures 12. However, if the total cross-section of the
apertures 12 is too large and the velocity of the water flowing through the apertures 12 is too
low then the resulting spray may be less pleasant for the user.
Referring next to Figures 2, 3, 4 and 5, each nozzle 15 is shaped and dimensioned to direct a
jet of fluid 16 onto a portion of an impingement surface 20 provided by a radially inner surface
21 of the annular portion 6 of the housing 1. The configuration of the impingement surface
portion 22 which the jet of fluid 16 impinges on is such as to cause the jet to radiate outward, to
flow to the trailing edge of the surface and to break into a stream of droplets 23. The stream of
droplets is preferably relatively wide relative to its thickness, and in preferred embodiment
appears as a substantially flat “fan” of water droplets.
The jet of fluid 16 typically impinges on the surface portion 22 at an angle of between around
°- 40° most preferably around 25°. Lower angles provide a narrower, more forceful spray
with larger droplets, and higher angles provide a wider, softer, less controllable spray with
smaller droplets.
The jet of fluid 16 preferably impinges on the surface portions between 1mm and 14mm from
the lower or trailing edge 19 of the surface, most preferably around 2mm. It is preferred that the
jet impinge close to the edge of the surface so as to reduce the amount of energy the water flow
loses to friction as it flows over the surface portion. As is described further below, the
impingement surface portion 22 may be substantially flat, or may be curved along one or two
axes.
As is best seen in Figure 5, the stream of droplets 23 from each impingement surface portion
typically has an elongate transverse cross section 24, for example an elongate ellipse. The
elongate cross-section 24 has a longitudinal axis 25 which is parallel to the “plane” of the stream
of droplets. The stream of droplets 23 also has a geometric centreline 26, as shown.
As is described further below, the configuration of nozzle 15 and its associated impingement
surface portion 22 may be varied to in order to vary the angle of the geometric centreline 26 of
the stream of droplets 23, the width of the stream of droplets 23 and the orientation of the
longitudinal axis 25.
Those skilled in the art will appreciate that orientation of the longitudinal axis 25 of each stream
of droplets is a function of both the orientation of the jet of water created by the respective
nozzle 15, and the orientation of the respective impingement surface portion 22. A number of
different combinations of water jet orientation and impingement surface portion orientation may
be used to create a stream of droplets having substantially the same geometric centreline
orientation and/or longitudinal axis orientation. However, the stream of droplets produced is
preferably substantially coplanar with the portion of the impingement surface which is adjacent
the trailing edge of the impingement surface portion. That is, the spray does not rebound off the
surface portion to any great extent, but rather flows along it to the trailing edge.
Referring next to Figures 6a and 6b, in one embodiment the shower head 100 is provided with a
first group of nozzles (not shown) and respective impingement surface portions 22a which are
configured to create streams of droplets 23a which have diverging geometric centres 26a.
A second group of nozzles (not shown) and respective impingement surface portions (not
shown) are configured to create streams of droplets 23b which have substantially parallel
geometric centrelines 26b.
A third group of nozzles (not shown) and respective impingement surface portions 22c are
configured to create streams of droplets 23c which have substantially converging geometric
centrelines 26c.
In this way the overall spray pattern created by the shower head does not have an area in the
centre which is substantially not covered, even in embodiments where the shower head has a
substantially annular shape, as shown in Figures 1-8.
As is explained above, a number of different combinations of water jet orientation and
impingement surface portion orientation may be used to create a stream of droplets having
substantially the same geometric centreline orientation and/or longitudinal axis orientation.
Correspondingly, variations in the orientation of the geometric centreline may be created by
varying the orientation of the water jet, the impingement surface portion, or both.
In some versions of the embodiment shown in Figures 6a and 6b the angle of the jets created
by the nozzles in each group of nozzles may be substantially rotationally symmetrical around
the centreline of the annular shower head, with the diverging, parallel and converging
characteristics of the different streams of droplets 23a, 23b, 23c being created by differing
orientations of the respective impingement surface portions 22a, 22c.
In other versions the various impingement surface portions may be rotationally symmetrical
about the centreline of the annular shower head, with the variations in the spray pattern
produced being a result of differences in the orientation of the water jets. In some embodiments
some or all of the respective impingement surface portions may be parts of a single
substantially continuous impingement surface.
In another embodiment of the invention, shown in Figures 7a and 7b, the orientation of the
geometric centreline 26 of each stream of droplets 23 may be substantially rotationally
symmetrical about the centre of the annular shower head. However, the orientation of the
impingement surface portions 22 (obscured behind narrow apertures in the face of the spray
head) may be non-parallel to a tangent T to a notional curve C on which the impingement
surface portions 22 lie. This orientation of the impingement surface portions means that the
longitudinal axis 25 of each droplet stream 23 is also non-tangential to the curve C. In this way
at least part of each stream of droplets 23 is directed towards a centre of the notional curve.
Figures 8a and 8b show another example of an embodiment which is similar to that described
above with reference to Figures 7a and 7b. In Figures 8a and 8b the droplet streams are shown
diagrammatically as two dimensional sprays or “fans” of water, although those skilled in the art
will appreciate that the droplet stream will in practice have a thickness, albeit a thickness which
is much smaller than the width dimension.
In the embodiment shown in Figures 8a and 8b the longitudinal axis 25 of each stream 23 is
parallel to a tangent of the curve on which the nozzles lie. The streams are directed so that the
geometric centreline of each stream of droplets has a direction component in the tangential
direction, and a direction component toward the centre of the circular housing (that is, the centre
of the droplet stream is directed slightly inward and sideways), as best seen in Figure 8b. In this
way, one side of each stream of droplets is directed towards the interior of the overall spray
pattern created. In this embodiment the impingement surface portions (not shown) are
substantially tangential to the notional curve C, with the trailing edge of the surface portions
angled slightly inward in order to impart the inward direction component to droplet stream. The
nozzles (not shown) are configured to create jets of fluid which have a directional component
which is tangential to the notional curve.
Referring next to Figure 9, an alternative embodiment of a showerhead according to the present
invention is generally referenced by arrow 200.
The shower head 200 has an elongate body 30. A plurality of nozzles are provided (not shown).
The nozzles are arranged in a substantially collinear pattern.
The nozzles direct jets of water towards respective impingement surfaces 22, in order to create
streams of droplets 23. As with the embodiments described above, the streams of droplets 23
have elongate cross-sections.
In the embodiment shown, the longitudinal axes 25 of the elongate cross-sections of the
streams of droplets 23 are substantially parallel with each other, although in alternative
embodiments they may be non-parallel. The elongate axes 25 are substantially orthogonal to a
notional line on which the water nozzles are arranged.
The streams of droplets 23 also have geometric centrelines 26 which in the embodiment shown
in Figure 9 are also substantially parallel.
Referring next to Figure 10, a variation of the embodiment shown in Figure 9 is generally
referenced by arrow 201. This embodiment varies from the embodiment shown in Figure 9 in
that the geometric centrelines 26 of the streams of droplets are divergent rather than parallel.
Referring next to Figure 11, a variation of the embodiment shown in Figure 10 is generally
referenced by arrow 202. In this embodiment the longitudinal axes 25 are rotated 90 degrees
so that the “planes” of the droplet streams are substantially parallel to the notional line on which
the nozzles lie. The geometric centrelines 26 are also divergent, as they are in the embodiment
shown in Figure 10.
Referring next to Figures 12-15, a variation of the embodiment shown in Figures 1-4 is generally
referenced by arrow 300. In this embodiment, a conduit member 27 is provided within the
handle portion 2. The conduit member 27 is provided with an inlet 4 and an outlet 5. The outlet
5 is sealed to an inlet 28 in the annular body 29. In this embodiment the annular body 29
comprises a main annular body 30 and a cap 31. The main annular body 30 has an internal
conduit 32 which connects the inlet 28 with the nozzles 15. In contrast to the embodiments
shown in Figures 1-4, the outer housing 1 is not subject to water pressure, and so be made of
less strong material that the annular body 29 and the conduit member 27. In one embodiment
the outer housing 1 may be made of ABS plastic. The annular body 29 and the conduit member
27 are preferably made from a suitable polyester polymer or a PPO/PS blend.
In the embodiment shown in Figures 12-15 the impingement surface portions 22 may be
provided on a separate impingement surface member 33. This may allow the impingement
surface member 33 to be manufactured from a different material to the outer housing 1 and/or
the annular member 29. For example, in one embodiment the impingement surface member 33
may be manufactured from a material which is substantially hydrophobic, for example PTFE.
This may assist in preventing large droplets from agglomerating. In another embodiment the
impingement surface member 33 may be manufactured from an elastomeric material such as
silicone or a thermoplastic elastomer, which will deform slightly under the pressure of the water
jets. This deformation may assist in reducing limescale buildup on the impingement surface
portions.
Referring next to Figures 16a-16c, the applicant has found that in some embodiments it is
advantageous for the impingement surface portion to be curved in the longitudinal and/or
transverse directions. The impingement surface portion 22 may be substantially concave in
transverse cross-section, as shown in Figure 16a, convex in transverse cross-section, as shown
in Figure 16b, or may have an undulating transverse cross-section, as shown in Figure 16c. In
each case, the transverse cross-section of the stream of droplets 23 produced has a shape
substantially corresponding to the contour of the impingement surface portion. Impingement
surface portions 22 having the profile shown in Figures 16a-16c may be used in any of the
embodiments described above. In some embodiments a combination of curved and
substantially flat impingement surface portions may be used. In other embodiments just one
type of curved profile may be used, while in still further embodiments a mixture of curved
profiles may be used.
Referring next to Figure 17, in some embodiments the overall thickness of the member 33
providing the impingement surface portion 22 may be reduced by shaping the member 33 such
that the impingement surface portion 22 is curved when viewed in longitudinal cross-section. In
a preferred embodiment a shower head may be provided with a plurality of impingement surface
portions of this general shape, with angle A (the angle of the lower or trailing surface of the
impingement surface 22) being varied between respective impingement surfaces to provide a
required spray pattern, but angle B (the angle between the impinging water jet and the upper
portion of the impingement surface 22) being substantially constant.
Referring next to Figures 13 and 18 in particular, in preferred embodiments the stream of
droplets travels through an aperture in the shower head. The aperture is preferably no more
than 3mm wide, more preferably less than 1mm. In the embodiment shown the aperture is an
annular slot 34 which is provided between the impingement surface portion 22 and an adjacent
surface 35 of the annular member 29. The width W of the slot 34 is preferably less than 3mm
wide when measured in a direction which is orthogonal to the plane of the impingement surface
portion (in this instance the radial direction). By keeping the width of the slot as narrow as
possible without impeding the spray pattern formed by the impingement surface 22, any
droplets which accumulate on the interior surfaces around the impingement surface portion 22
are re-absorbed into the main spray pattern rather than falling from the showerhead as a
discrete droplet or “drip”. In preferred embodiments the adjacent surface 35 may be defined by
an annular skirt portion 36 which is part of the annular member 29.
Those skilled in the art will appreciate that although the invention has been described with
reference to a hand-held showerhead, other embodiments of the spray head are also possible,
for example fixed or “drencher” type embodiments.
Unless the context clearly requires otherwise, throughout the description and the claims, the
words “comprise”, “comprising”, and the like, are to be construed in an inclusive sense as
opposed to an exclusive or exhaustive sense, that is to say, in the sense of “including, but not
limited to”.
Where in the foregoing description, reference has been made to specific components or
integers of the invention having known equivalents, then such equivalents are herein
incorporated as if individually set forth.
Although this invention has been described by way of example and with reference to possible
embodiments thereof, it is to be understood that modifications or improvements may be made
thereto without departing from the scope of the appended claims.