HUGHES ANTHONY DOUGLAS (GB)
WO2009142912A1 | 2009-11-26 | |||
WO2006038316A1 | 2006-04-13 |
CLAIMS 1 . An eyewash fountain nozzle unit comprising: an eyewash fluid outlet port shaped to define a first eyewash fluid outlet opening, a second eyewash fluid outlet opening, and a flow constriction eyewash fluid outlet opening extending between the first eyewash fluid outlet opening and the second eyewash fluid outlet opening in fluid communication therewith; wherein the cross-sectional area of the flow constriction opening is less than the cross- sectional area of either of the first eyewash fluid outlet opening and the second eyewash fluid outlet opening and thereby presents a fluid flow constriction relative thereto permitting formation of a bridging body of discharged eyewash fluid between respective upwardly directed eyewash fluid discharge streams formable by the first eyewash fluid outlet opening and the second eyewash fluid outlet opening concurrently. 2. An eyewash fountain nozzle unit according to claim 1 in which the flow constriction fluid outlet opening is defined by a gap at the terminal end of a fluid diverger part which extends inwardly from the peripheral edge of the fluid outlet port. 3. An eyewash fountain nozzle unit according to claim 2 wherein the gap is presented between said terminal and an opposing periphery of the outlet port. 4. An eyewash fountain nozzle unit according to claim 2 wherein the gap is defined by the separation between opposing terminal ends of two said fluid diverger parts which each extend inwardly from diametrically opposed parts of the peripheral edge of the fluid outlet port. 5. An eyewash fountain nozzle unit according to any of claims 2 to 4 wherein the fluid diverger part(s) extend towards the centre, diameter or peripheral edge of the fluid outlet port, and terminate respectively before reaching said centre, diameter or edge thereby to leave said respective centre, diameter or edge region of the port open and thereby to place the first and second eyewash fluid outlet openings in fluid communication. 6. An eyewash fountain nozzle unit according to any of claims 2 to 5 in which one, some or each said fluid diverger part presents a wedge-shape in cross-section along at least some of its length which wedge shape converges in a direction inwardly into the fluid conduit of the nozzle unit to define an inner edge therein. An eyewash fountain nozzle unit according to claim 6 in which the convergence angle, Θ, at which convergent wedge faces meet to define the edge of the wedge, is a value between about 15 degrees and 45 degrees. An eyewash fountain nozzle unit according to any preceding claim in which the eyewash fluid outlet port is shaped such that both the first eyewash fluid outlet opening and the second eyewash fluid outlet opening are wider than the width of the flow constriction eyewash fluid outlet opening. An eyewash fountain nozzle unit according to claim 8 in which the ratio of the cross- sectional area of the flow constriction eyewash fluid outlet opening to the combined cross sectional area of the of the first and second eyewash fluid outlet openings is in the range of about 1/160 to about 1/40 10. An eyewash fountain nozzle unit according to any preceding claim in which the eyewash fluid outlet port is shaped such that the first eyewash fluid outlet opening and the second eyewash fluid outlet opening are arranged substantially symmetrically about the flow constriction eyewash fluid outlet opening. 1 1 . An eyewash fountain nozzle unit according to any preceding claim in which the shape of the first eyewash fluid outlet opening mirrors the shape of the second eyewash fluid outlet opening such that the shape of the eyewash fluid outlet port is substantially symmetrical about the flow constriction eyewash fluid outlet opening. 12. An eyewash fountain nozzle unit according to any preceding claim in which the cross- sectional area of the first eyewash fluid outlet opening is substantially the same as the cross-sectional area of the second eyewash fluid outlet opening. 13. An eyewash fountain nozzle unit according to any preceding claim in which the eyewash fluid outlet port is shaped such that the flow constriction eyewash fluid outlet opening is substantially centrally positioned therein. 14. An eyewash fountain nozzle unit according to any preceding claim in which the flow constriction eyewash fluid outlet opening is substantially linear. 15. An eyewash fountain nozzle unit according to any preceding claim comprising an eyewash fluid inlet opening in fluid communication with the eyewash fluid outlet port via an eyewash fluid conduit of the nozzle unit, and an aerator part within the eyewash fluid conduit for aerating eyewash fluid. 16. An eyewash fountain assembly comprising the eyewash fountain nozzle unit according to any preceding claim. 17. A method of washing human eyes comprising: providing an eyewash fountain nozzle unit according to any preceding claim; discharging eyewash fluid through the eyewash fluid outlet port to form a bridging body of discharged eyewash fluid between respective upwardly directed eyewash fluid discharge streams formed by the first eyewash fluid outlet opening and the second eyewash fluid outlet opening concurrently; and, washing one or both eyes using discharged eyewash fluid. 18 An eyewash fountain nozzle unit substantially as disclosed in any one embodiment hereinbefore and/or with reference to the accompanying drawings. 19 A method of washing human eyes substantially as disclosed hereinbefore. |
FIELD OF THE INVENTION The invention relates to eyewash stations and outlet nozzles therefor. In particular, though not exclusively, the invention relates to emergency eyewash stations for use in laboratory, industrial or other environments in which there is a need to be able to wash away irritants or contaminants (e.g. chemicals, powders or dust) from human eyes. BACKGROUND
Eye-washing stations or fountains are known in the art for use in flushing toxins and contaminants of human eyes in laboratory or industrial environments. This might be necessary in an emergency, or as part of a routine decontamination process.
An important part of the eye-washing process is to appropriately direct water into the eyes in a water flow direction across the eye(s) outwardly such that a flushing action occurs in a leftward direction in a left eye and in a rightward direction in a right eye. This aims to prevent the contaminants being urged by the flow of water inwards, against or into the tear ducts or sinus cavities.
However, it is difficult to achieve this result effectively due to the relatively small inter-ocular separation between human eyes and the constraints of washing station/fountain design. The invention aims to provide an improved eye-washing station.
SUMMARY
In a first aspect, the invention provides an eyewash fountain nozzle unit comprising, an eyewash fluid outlet port shaped to define a first eyewash fluid outlet opening, a second eyewash fluid outlet opening, and a flow constriction eyewash fluid outlet opening extending between the first eyewash fluid outlet opening and the second eyewash fluid outlet opening in fluid communication therewith. The cross-sectional area of the flow constriction opening is less than the cross-sectional area of either of the first eyewash fluid outlet opening and the second eyewash fluid outlet opening and thereby presents a fluid flow constriction relative thereto permitting formation of a bridging body (e.g. a "web") of discharged eyewash fluid between respective upwardly directed eyewash fluid discharge streams formable by the first eyewash fluid outlet opening and the second eyewash fluid outlet opening concurrently. In this way, a user may position his/her head such that their eyes meet respective of the two eyewash fluid discharge streams and such that the bridge of their nose meets the bridging body of discharged fluid thereby to extensively bath his/her face at and between the eyes, using the wedge-shape of the bridge of their nose to direct the flow of eyewash water across their eyes to more effectively flush contaminants from their eyes in an outward direction away from the eyes, nose (nasal cavity) and the tear ducts which are otherwise vulnerable to contamination.
The flow constriction fluid outlet opening may be defined by a gap (e.g. linear, e.g. of uniform width) defined at the terminal end of a fluid diverger part (e.g. spoke, diameter) which extends inwardly (e.g. radially/diametrically) from the peripheral edge of the fluid outlet port. The gap may be between that terminal and an opposing periphery of the outlet port, or by the separation between opposing terminal ends of two fluid diverger parts (e.g. spokes) which extend inwardly (e.g. radially) from diametrically opposed parts of the peripheral edge of the fluid outlet port. The fluid diverger part(s) may extend towards the centre, diameter or peripheral edge of the fluid outlet port, terminating before reaching the centre, diameter or edge to leave the centre, diameter or edge region of the port open and joining the first and second eyewash fluid outlet openings together.
One, some or each fluid diverger part may be wedge-shaped in cross-section along some of its length, or substantially its full length and may present two substantially flat wedge faces along its length (or part thereof) which converge inwardly into the fluid conduit of the nozzle unit to define an inner edge therein. This inner edge may be presented to fluid flowing through the bore of the fluid conduit towards the fluid outlet port, in use. The thickness or width of an/each diverger part may increase in the direction from within the fluid conduit towards the terminal end of the nozzle unit at the fluid outlet port. The wedge angle, Θ, at which the convergent wedge faces meet to define the edge of the wedge, is preferably a value between about 15 degrees and 45 degrees, more preferably a value between about 20 degrees and 40 degrees, even more preferably a value between about 25 degrees and 35 degrees, such as about 30 degrees. This convergence to an inwardly-facing edge may assist in inducing a reciprocal divergence in the flow of water within the fluid conduit at the fluid outlet port, into two diverging eyewash fluid discharge stream flows which have passed through the first and second eyewash fluid outlet openings. The divergent discharge streams may be bridged by a body of bridging fluid which has not flowed past the wedge surfaces of the diverger parts but has, instead, flowed through the flow constriction eyewash fluid outlet opening. The eyewash fluid outlet port is preferably shaped such that the first eyewash fluid outlet opening and the second eyewash fluid outlet opening are arranged substantially symmetrically about the flow constriction eyewash fluid outlet opening. The shape of the first eyewash fluid outlet opening may mirror the shape of the second eyewash fluid outlet opening such that the shape of the eyewash fluid outlet port is substantially symmetrical about the flow constriction eyewash fluid outlet opening. The cross-sectional area of the first eyewash fluid outlet opening may be substantially the same as the cross-sectional area of the second eyewash fluid outlet opening.
The eyewash fluid outlet port may be shaped such that the flow constriction eyewash fluid outlet opening is substantially centrally positioned therein.
The flow constriction eyewash fluid outlet opening is preferably substantially linear.
The eyewash fluid outlet port is preferably shaped such that both the first eyewash fluid outlet opening and the second eyewash fluid outlet opening are wider than the width of the flow constriction eyewash fluid outlet opening. The ratio of the cross-sectional area of the flow constriction eyewash fluid outlet opening to the combined cross sectional area of the of the first and second eyewash fluid outlet openings may be in the range of about 1/160 to about 1/40, or more preferably may be in the range of about 1/60 to about 1/120, or yet more preferably in the range of about 1/70 to about 1/100, or even more preferably in the range of about 1/75 to about 1/90, such as about 1/80. This permits control of the relative percentage of fluid flow through the flow constriction fluid outlet opening to induce formation of a web of fluid between discharged fluid flow streams from the first and second fluid outlet openings. For example, if the maximal width dimension of the fluid outlet port as a whole is about 20mm, then the width of the constriction eyewash fluid outlet opening within it may be in the range of about 0.5mm to about 2.0mm, preferably about 1 .2mm.
The eyewash fountain nozzle unit may comprise an eyewash fluid inlet opening in fluid communication with the eyewash fluid outlet port via an eyewash fluid conduit of the nozzle unit, and an aerator part within the eyewash fluid conduit for aerating eyewash fluid.
In a second aspect, the invention may provide an eyewash fountain assembly comprising the eyewash fountain nozzle unit as described above.
In a third aspect, the invention may provide a method of washing human eyes comprising, providing an eyewash fountain nozzle unit according to any preceding claim, discharging eyewash fluid through the eyewash fluid outlet port to form a bridging body of discharged eyewash fluid between respective upwardly directed eyewash fluid discharge streams formed by the first eyewash fluid outlet opening and the second eyewash fluid outlet opening concurrently, and washing one or both eyes using discharged eyewash fluid. The first and second eyewash fluid outlet openings may be left and right eyewash fluid outlet openings, respectively. Herein, references to "fluid" include, preferably, a reference to water, though the invention is not limited to use with water. References to "right" and "left" eyewash fluid outlet openings are not intended to limit to absolute spatial positions of orientations of the openings, but are references to a correspondence with the left and right eyes of a person. The term, "cross-sectional" in relation to an area of an opening of an outlet port may preferably be taken to refer to, for example, a section taken or 'cut' in a direction across the longitudinal axis of a nozzle comprising the outlet port, so as to expose the gauge, bore, size or effective area of the opening presented to the flow of fluid through it.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 shows a nozzle according to an embodiment of the invention, in cross-section;
Figure 2 shows a nozzle according to an embodiment of the invention, in plan view;
Figures 3 and 4 show divergent eyewash fluid discharge flow streams bridges by a body of eyewash fluid;
Figure 5 shows a nozzle according to an embodiment of the invention, in plan view; Figure 6 shows a nozzle according to an embodiment of the invention, in cross-section; Figure 7 shows a nozzle according to an embodiment of the invention, in perspective view; Figure 8 shows a nozzle according to an embodiment of the invention, in plan view; Figure 9 shows a nozzle according to an embodiment of the invention, in cross-section;
Figure 10 shows a nozzle according to an embodiment of the invention, in perspective view.
DETAILED DESCRIPTION In the drawings, like items are assigned like reference symbols.
Referring to Figure 1 , an eyewash fountain nozzle unit 1 is shown in cross-section. Figure 2 shows a top view of the nozzle unit. The nozzle unit comprises a fluid inlet opening 7 in fluid communication with a fluid outlet port 2 via a fluid conduit of the nozzle unit. An aerator part 10 is positioned within the bore of a fluid conduit 13 to extend across the bore for receiving eyewash fluid from the inlet opening 7, and for aerating that fluid as it flows through the aerator. Connected to the aerator 10 and located before the fluid outlet port 2, within the fluid conduit, a grill 1 1 (optional) extends transversely across the bore of the fluid conduit. The grill serves to inhibit ingress of external debris into the fluid conduit via the fluid outlet port, while permitting eyewash fluid to pass there through to the fluid outlet port 2 for use in an eye- washing operation. Aerators of known type may be used such as would be readily apparent and available to the skilled person. The nozzle comprises a two-piece assembly including an upper externally-threaded male fitting 12 possessing an upper through-bore terminating with the fluid outlet port 2, and a lower internally-threaded female fitting 8 possessing a lower through-bore which starts at the fluid inlet opening 7 and terminates at the inlet end of the upper through-bore. The lower through- bore is threaded internally at the fluid inlet opening to allow the nozzle unit to be screw-fitted to a water supply part.
The lower fitting 8 is adapted to receive and reciprocally cooperate with the upper fitting to form a water-tight screw-fit which brings the lower through-bore in to register, and fluid communication, with the upper through-bore. A flow restrictor part 9 is housed within the lower through-bore between the fluid inlet end and the aerator 10. The flow restrictor extends across that bore. As is known in the art, a flow restrictor is arranged to regulate the rate of flow of fluid through it to be a substantially constant fluid outflow in response to a range of different upstream fluid supply pressures. In preferred embodiments, the flow restrictor is arranged to maintain a substantially constant water outflow rate of between about 1 .5 litres per minute and about 30 litres per minute, more preferably between about 1 1 .4 litres per minute and about 20 litres per minute, such as, for example, about 12 litres per minute. This may be in response to a water supply pressure of between about 20 psi and about 85 psi, or more preferably between about 20 psi and about 55 psi, such as for example, about 40 psi. The fluid outlet port 2 is shaped to define a substantially semi-circular first eyewash fluid outlet opening 4 and a substantially semi-circular second eyewash fluid outlet opening 3, with a substantially linear flow constriction fluid outlet opening 5 extending between them in fluid communication with both. The flow constriction fluid outlet opening 5 is defined by a linear gap of uniform width defined by the separation between opposing terminal ends of two fluid diverger spokes 6. Each fluid diverger spoke extends radially inwardly from diametrically opposed parts of the peripheral edge of the fluid outlet port 2, towards the centre of the port, terminating before reaching the centre to leave the centre region of the port open and joining the first and second eyewash fluid outlet openings together. The maximal width dimension (diameter) of the fluid outlet port as a whole is about 20mm in this example, and the width of the constriction eyewash fluid outlet opening within it may be in the range of about 0.5mm to about 2.0mm, preferably about 1 .2mm. This ratio of dimensions may preferably be preserved if the overall dimensions of the nozzle unit are scaled. It has been found that by carefully controlling the relative percentage of fluid flow through the flow constriction fluid outlet opening of embodiments of the invention, permits a desirably large web of water (17, Fig.3 & Fig.4) to form between diverging discharged fluid flow streams, in use.
Each fluid diverger spoke is wedge-shaped in cross-section along substantially its full length and presents two substantially flat wedge faces along its length which converge inwardly into the fluid conduit of the valve unit to define an inner edge therein which is presented to fluid flowing through the bore of the fluid conduit towards the fluid outlet port 2, in use. Thus, the thickness or width of each diverger spoke increases in the direction from within the fluid conduit towards the terminal end of the nozzle unit at the fluid outlet port. The wedge angle, Θ, at which the convergent wedge faces meet to define the edge of the wedge, is preferably a value between about 15 degrees and 45 degrees, more preferably a value between about 20 degrees and 40 degrees, even more preferably a value between about 25 degrees and 35 degrees, such as about 30 degrees. This convergence to an inwardly-facing edge induces a reciprocal divergence in the flow of water within the fluid conduit at the fluid outlet port 2, into two diverging eyewash fluid discharge stream flows which have passed through the first and second eyewash fluid outlet openings (3, 4). The divergent discharge streams are bridged by a body of bridging fluid which has not flowed past the wedge surfaces of the diverger spokes but has, instead, flowed through the flow constriction eyewash fluid outlet opening between the substantially flat, parallel and opposed terminal end surfaces of the diverger spokes. Figure 3 and Figure 4 show examples of this fluid effect.
These two semi-circular first/second eyewash fluid outlet openings oppose each other along their straight sides substantially symmetrically across the flow constriction fluid outlet opening 5 which joins them. The shape of the first fluid outlet opening mirrors the shape of the second fluid outlet opening such that the shape of the fluid outlet port is substantially symmetrical about the flow constriction fluid outlet opening. The flow constriction fluid outlet opening 5 is substantially centrally positioned within the shape of the fluid outlet port 2 and within the upper surface of the body of the nozzle 1 . Accordingly, the cross-sectional area of the first fluid outlet opening is substantially the same as the cross-sectional area of the second fluid outlet opening with the result that the fluid outlet port as a whole is shaped such that both the first fluid outlet opening and the second fluid outlet opening are wider than the width of the flow constriction fluid outlet opening.
In particular, the cross-sectional area of the flow constriction opening 5 is less than the cross- sectional area of either of the first fluid outlet opening 3 and the second fluid outlet opening 4 and thereby presents a fluid flow constriction. This induces the formation of a bridging body of discharged eyewash fluid (17, figures 3 and 4) between respective upwardly directed eyewash fluid discharge streams formed by the first fluid outlet opening and the second fluid outlet opening, concurrently, when the nozzle is in use. Figures 3 and 4 show examples of this structure in the discharge flow of aerated eyewash water discharged from a nozzle unit according to an embodiment of the invention, in use.
The main eyewash fluid discharge streams (15,16) may be used to flush contaminants from the eyes of a user by placing the user's face at a position above the valve unit 1 such that the inter-ocular separation of the user's eyes matches the separation of the diverging discharge fluid flows (15,16). Concurrently, or independently, the user may position his/her head such that the bridge of their nose meets the bridging body of discharged fluid 17 and thereby extensively bathes his/her face at and between the eyes, using the wedge-shape of the bridge of their nose to direct the flow of eyewash water across their eyes to more effectively flush contaminants from their eyes in an outward direction away from the eyes, nose (nasal cavity) and the tear ducts which are otherwise vulnerable to contamination.
Figure 5, Figure 6 and Figure 7 show a plan, cross-sectional and perspective view of another embodiment of the nozzle 19 in which the fluid outlet port 20 defines a single labyrinth slot (22, 23, 24) comprising a first 22 and second 23 labyrinth slot parts of symmetrically substantially identical shape and size arranged at opposite sides of a single diverger wedge 21 which extends from one peripheral edge of the outlet port diametrically across the outlet port terminating adjacent an opposite peripheral edge thereof to define a gap forming the flow constriction eyewash fluid outlet opening 24 extending between the first eyewash fluid outlet opening and the second eyewash fluid outlet opening in fluid communication therewith. The labyrinth slot comprises a side-by-side series of successive adjacent parallel slot-shaped opening sections in which the end of one opening section is continuous with the start of the next via a transverse bridging slot. One such bridging slot defines the slot-shaped flow constriction eyewash fluid outlet opening 24. The nozzle unit comprises a fluid conduit 18 containing a flow restrictor 9, an aerator 10 (with optional grill 1 1), each arranged in succession between the fluid inlet opening 25 of the nozzle and its fluid outlet port 20.
Figure 8, Figure 9 and Figure 10 show a plan, cross-sectional and perspective view of another embodiment of the nozzle 30 in which the fluid outlet port defines a grill (34, 36) comprising a first 31 and second 32 set of grill slots arranged at opposite sides of a single transverse (e.g. perpendicular) diametric slot 33 which extends from one peripheral edge of the outlet port diametrically across the outlet port terminating adjacent an opposite peripheral edge thereof to define a gap between the first and second grill slots, and defining the flow constriction eyewash fluid outlet opening in fluid communication therewith. The grill slots comprise a side- by-side series of successive adjacent parallel slot-shaped opening sections which extend in parallel towards the flow constriction eyewash fluid outlet opening 33. Each slot of the first and second grill slots is angled to direct fluid flow out of the fluid outlet port at an angle (upwardly and to one side) to the axis of the fluid conduit 40 of the nozzle. The first and second set of grill slots are angled differently to direct fluid flow out of the part of the fluid outlet port they define, respectively, at an opposite angle relative to the axis of the fluid conduit 40 (upwardly and to opposite sides). This provides a divergence of discharge fluid flow streams, while still being bridged by a body of bridging water outflowing through the flow constriction eyewash fluid outlet opening 33.
Each grill slot terminates at a fin part 36 which extends across some but not all of the width of the respective grill slot, leaving an opening with which the grill slot makes fluid communication with the flow constriction eyewash fluid outlet opening and thereby with each other grill slot of the fluid outlet port.
The nozzle unit comprises a fluid conduit 40 containing a flow restrictor 9, an aerator 10 (with optional grill 1 1), each arranged in succession between the fluid inlet opening 35 of the nozzle and its fluid outlet port. Each feature disclosed in this specification (including any accompanying claims, abstract and drawings), may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features. The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process. The embodiments described herein are not intended to be limiting and are provided to illustrate example(s) of the invention, to aid understanding. It is to be understood that modifications, variants and alternatives to elements within these embodiments, such as would be readily apparent to the skilled person, are intended to be encompassed within the scope of the invention, e.g. as defined by the claims.