GB2193446A - Spray heads - Google Patents

Abstract

A spray head includes a chamber in which three concentric rings 21, 31 and 41 are housed, and means to supply water thereto. An outer ring 21 is attached to the chamber, serrations 5 formed internally of the ring defining in co-operation with the wall of an intermediate ring 31 apertures through which water is emitted. Similar serrations 6 are formed on ring 31. At least one of the rings is moveable relative to an adjacent ring against a spring contained in the head. An annular O-ring is located between adjacent rings. The serrations are inwardly tapered whereby as the water pressure in the head increases and forces a ring outwardly relative to an adjacent ring, an increased flow of water is permitted through the aperture defined by the serration and adjacent wall thus maintaining a constant water pressure through the aperture. <IMAGE>

Description

SPECIFICATION Spray heads The present invention relates to improvements in apparatus for spraying liquids, especially shower bath spray heads.

Fluctuations in water pressure to spray heads, for example those used in shower bath assemblies, cause the force of water emitted through the spray head orifices to vary. Thus at high pressures the "spray" is said to be hard whilst at lower pressures a "soft" spray results and at very low pressures there may be a total loss in spray patterns. For spray heads used in shower baths it is preferable that the spray be "soft" although at the same time a definite spray pattern is required to be retained.

Co-pending application no. 8504635 (publication no. 2,155,361 A) describes a design of spray head that seeks to overcome the problems associated with variable water pressure, however, this design has not proved to be entirely successful.

We have now, therefore, developed an alternative and improved design of spray head which provides a substantially continuous "soft" spray of water from a spray head over a wide range of water pressures.

As with earlier designs the effect is obtained by providing, within the spray head, means whereby the size of the spray apertures is increased with increasing water pressure, a decrease in water pressure resulting in a decrease in aperture size.

Accordingly, therefore, the present invention provides a liquid spraying device comprising a spray head, a means to supply liquid under pressure into a chamber located within the said head, said spray head including a face element forming an outer wall of the said chamber and consisting of a plurality of annular concentric spray rings each ring having inner and outer peripheral walls extending substantially axially of the face element, the outer peripheral wall of one ring lying adjacent the peripheral wall of a second ring, spray ring apertures being formed by axially directed grooves or serrations cut in the peripheral wall of one of two adjacent rings, and at least one of said spray rings being movable axially of said face element relative to an adjacent fixed ring and against resilient means contained within the said spray head, wherein an annular flow control member is located between adjacent spray rings, at least one of which is movable axially of the spray head in a fixed spatial relationship to the ring not including said serrations or grooves, the said serrations or grooves in said one ring being tapered inwardly from the face of the said spray head.

Preferably the flow control member is an 0ring formed from a resilient deformable material such as rubber. The said member may be located in a circumferential groove formed in the said ring and extending parallel to the face of the ring, the depth of the groove being such that the outer periphery of the member is proud of the ring wall.

One embodiment of the present invention will now be described with reference to the accompanying drawings in which: Figure 1 is a section through a spray head of the present invention; Figure 2 is a section through A-A of Fig. 1; Figure 3 is a section through B-B of Fig. 1; and Figure 4 is a section through C-C of Fig. 1.

The spray head comprises a housing 1 providing a chamber 11. An outer spray ring 2 is secured, such as by adhesive bonding or welding, to housing 1 and includes four inwardly directed ribs 21, 22, 23 and 24 extending upwardly into chamber 11 and supporting a platform 25 from which depends a spring support member 26. Ribs 21 and 22 include shoulders 27 and 28 formed at the base thereof and which extend radially inwardly of ring 2, ribs 23 and 24 include identical shoulders (not shown).

A second annular ring 3 is located concentrically within ring 2, upper annular face 36 engaging shoulders 27 and 28 of ribs 21 and 22 whereby upward movement of ring 3 is controlled. Four ribs 31, 32, 33 and 34 extend upwardly from ring 3 and are directed inwardly to support a piatform 35 including a central aperture 37 and through which passes a spring support pin 40. Ribs 31 and 32 include shoulders 37 and 38 formed at the base thereof and which extend radially inwardly of ring 3. Ribs 33 and 34 include identical shoulders (not shown).

A third inner ring 4 is in the form of a disc the upper annular face 42 of which co-operates with shoulders 37 and 38 of ribs 31 and 32 to restrain upward movement of the ring.

A spring attachment member 41 extends inwardly of ring 4.

Inwardly tapered serrations 5 formed in the inner peripheral wall of ring 2 co-operate with the outer peripheral wall of ring 3 to provide a ring of apertures in the face of the spray head which apertures communicate via the serrations with the portion 12 of chamber 11 which lies within ribs 21 to 24.

A similar set of serrations 6 formed in the inner peripheral wall of spray ring 3 co-operate with the outer periphe,ral wall of disc member 4 to provide a second ring of apertures in the face of the spray head, which apertures communicate with portion 13 of chamber 11 which lies within rib members 31-34.

Tension spring 14 acts between depending member 26 and pin 40 to normally hold spray ring 2 at its innermost position and tension spring 15 acts between pin 40 and attachment member 41 to retain ring 4 in its inner most position.

Deformable rubber O-rings 9 and 10 are positioned in circumferential grooves 7 and 8 formed in the outer peripheral walls of rings 3 and 4 respectively. The depths of the grooves are arranged such that the outer peripheral surfaces of O-rings 9 and 10 are proud of the outer walls of rings 3 and 4 such that, with rings 3 and 4 in the position shown in Fig. 1 the rings 9 and 10 deform against the serrations 5 and 6 causing a partial blockage and thereby restricting the flow of water through the apertures.

In use, water enters chamber 11 and flows past ribs 21 to 24 into area 12 past ribs 31 to 34 into area 13 and into the inner ends of serrations 5 and 6. The water then flows past the deformable flow control members 9 and 10 and out of the aperture formed between the respective rings in the form oaf a spray.

Pressure of the water acting against rings 3 and 4 cause the rings to move downwardly against the restraining force of springs 14 and 15 causing the O-rings 9 and 10 to move along the tapered serrations 5 and 6 to increase the area through which the water flows. An increase in water pressure will cause the rings to move further downwardly which in turn causes the O-rings to move along the tapered serrations and further increase the area through which the water flows thereby maintaining a constant force of water flowing through the spray head apertures. In the event of a reduction in water pressure the rings 3 and 4 move inwardly toward their original position under the effect of springs 14 and 15 thus causing the O-rings to move upwardly against serrations 5 and 6 to reduce the water flow and again maintain a constant force of water issuing through the spray head apertures.

In the event that the shower head should become partially blqcked e.g., as a result of deposits building up from the water, the increase in pressure resulting from such blockage causes rings 3 and 4 to move outwardly against springs 14 and 15 to provide the same constant force of water flowing from the shower head.

It is clear from the foregoing that the actual pressure of water flowing through the spray head apertures will be determined by the tension in springs 14 and 15 which tension is seiected to provide a "soft" spray over a range of mains water pressures normally encountered by domestic users.

Claims (3)

1. A liquid spraying device comprising a spray head, means to supply liquid under pressure into a chamber located within the said spray head, said spray head including a face element forming an outer wall of the chamber and consisting of a plurality of annular concentric spray rings each ring having an inner and outer peripheral wall extending substantially axially of the face element, the outer peripheral wall of one ring lying adjacent the peripheral wall of a second ring, spray ring apertures formed in the face element by axially directed grooves or serrations out in the peripheral wall of one of two adjacent rings and at least one of said spray rings being movable axially of the face element relative to an adjacent fixed ring and against resilient means contained within the said spray head; ; wherein an annular flow control member is located between adjacent rings, at least one of which rings is movable axially of the spray head, in a fixed spatial relationship to the ring not including said grooves or serrations, and wherein the said grooves or serrations in said one ring are tapered inwardly from the face of the spray head.

2. The spray head according to claim 1 wherein the flow control member is an O-ring formed from a resilient deformable material.

3. A spray head accordng to claim 1 or claim 2 wherein the said flow control member is located in a circumferential groove formed in the said ring and extending parallel to the face of the ring, the depth of the groove being- such that the outer periphery of the member is proud of the ring wall.