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EP 0 668 110 B1 |
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EUROPEAN PATENT SPECIFICATION |
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Mention of the grant of the patent: |
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30.09.1998 Bulletin 1998/40 |
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Date of filing: 14.02.1995 |
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International Patent Classification (IPC)6: B05B 7/24 |
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Device for entraining a substance in a water flow
Vorrichtung zum Mitreissen einer Substanz in einem Wasserstrom
Dispositif pour entraîner une substance dans un courant d'eau
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Designated Contracting States: |
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AT BE CH DE DK ES FR GB GR IE IT LI LU MC NL PT SE |
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Priority: |
22.02.1994 GB 9403359
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Date of publication of application: |
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23.08.1995 Bulletin 1995/34 |
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Proprietor: MONSANTO COMPANY |
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St. Louis, Missouri 63167 (US) |
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Inventors: |
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- Cessford, Alan Charles
Llangollen,
Clwyd, Wales (GB)
- Cale, David Alan
Llanrug,
Caernarfon LL55 4RG,
Wales (GB)
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Representative: Godwin, Edgar James et al |
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MARKS & CLERK,
57-60 Lincoln's Inn Fields London WC2A 3LS London WC2A 3LS (GB) |
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References cited: :
EP-A- 0 138 380 US-A- 2 744 791 US-A- 2 926 857
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US-A- 2 061 932 US-A- 2 753 213 US-A- 5 100 059
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Note: Within nine months from the publication of the mention of the grant of the European
patent, any person may give notice to the European Patent Office of opposition to
the European patent
granted. Notice of opposition shall be filed in a written reasoned statement. It shall
not be deemed to
have been filed until the opposition fee has been paid. (Art. 99(1) European Patent
Convention).
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[0001] This invention relates to a device for entraining a substance, e.g. plant food, in
a flow of water.
[0002] GB-A-2 236 259 discloses a device comprising a cap adapted to be fitted to the open
top of a container filled with soluble plant food. The cap comprises a duct which
includes a venturi section for drawing concentrated solution from the container. Upstream
of the venturi section, the duct has a lateral orifice through which water flows into
the container under the pressure prevailing in the duct.
[0003] The construction of the device is expensive and includes an anti-siphon device or
non-return valve to prevent contaminants from being sucked back into the water supply
if there is a reduction or reversal of the main water pressure.
[0004] US-A-2 926 857 discloses a device in accordance with the pre-characterising part
of claim 1. The device includes a valve in a passageway communicating with the upper
surface of a base member (over which a stream of water flows), the underside of the
base member, and a suction duct.
[0005] The present invention provides a device for entraining in a flow of water a substance
contained in an open-topped container, the device comprising a cap adapted to be fitted
to the open top of the container, the cap comprising a water inlet section having
an inlet end which is connectable to a source of water under pressure and having a
bore which communicates between the inlet end and an outlet end and which forms the
water into a jet, and a base member and sidewalls delimiting an upwardly open cavity
into which the bore discharges, the upper surface of the base member including a bed
which slopes upwards in the downstream direction, the water jet impinging on the bed
downstream of the outlet end of the core and flowing as a stream over the bed towards
an exit of the cavity, the base member including a hollow depending portion defining
a suction duct having an upper end across which the water stream flows to cause a
reduction in pressure in the suction duct, and including means for communicating between
the upper surface and the underside of the base member, the said communicating means
being upstream of the suction duct and including an orifice which communicates with
the underside of the base member to divert water into the open-topped container, in
use,
characterised in that the communicating means includes a groove in the bed, which is aligned with the bore,
open at the end facing the bore, and closed by a step at the other end, the said orifice
communicating with the groove.
[0006] This structure ensures an air break consisting of a space open to the air between
the outlet end of the bore of the water inlet section and the location at which the
water comes into contact with the substance, thereby preventing suck-back of contaminated
water should there by a pressure drop or reversal in the bore. The water diverted
into the container can cause a continuous turbulent flow therein.
[0007] The inlet section, the base member, and the sidewalls can easily be made in one piece,
e.g. by injection moulding.
[0008] Optional and preferred features of the invention are set forth in the subsidiary
claims.
[0009] The invention will be described further, by way of example only, with reference to
the accompanying drawings, in which:
Figure 1 is a cross-section (taken on line I-I in Figure 2) through an entrainment
device fitted on a container;
Figure 2 is a plan view of the device;
Figure 3 is a side view, partly in axial cross-section, of a preferred embodiment
of the entrainment device;
Figure 4 is a front end view of the preferred embodiment;
Figure 5 is a rear end view of the preferred embodiment; and
Figure 6 is a plan view of the preferred embodiment.
Figure 7 shows a modified detail of Figure 6.
[0010] The device illustrated in Figures 1 and 2 comprises a one-piece moulded plastics
cap 1 with a mixing chamber 2 having an internally screw-threaded circumferential
wall 3 which is screwed onto the externally screw-threaded neck 4 of a transparent
container 6 filled with powdered plant food (not shown) which dissolves in water to
form a solution (which term includes colloidal solutions and dispersions).
[0011] The cap 1 includes a water inlet section 7 having a bore 8 of circular cross-section
which progressively decreases in diameter from an inlet end 8a to an outlet end 8b.
The inlet end of the inlet section 7 is constituted by a spigot 9, accommodating an
O-ring 11 (Fig. 1), for connection to a conventional click-fitting connector (not
shown) providing communication with the main water supply. The water, under mains
pressure, accelerates along the gradually convergent bore 8 and leaves the outlet
end 8b as a jet which enters an upwardly open divergent cavity 12 defined by a base
member 13 and sidewalls 14. The upper surface of the base member 13 includes a bed
16 on which the water jet impinges and forms a divergent stream flowing towards a
convex ramp 17 rising towards a lip or ridge 18 at a downstream exit of the cavity
12. The surface over which the water flows acts to direct the flow in such a way as
to create an even fan-shaped spray with fine droplets, suitable for irrigation in
a wide range of garden situations. The lip 18 enhances the formation of fine droplets.
Two inward projections 19 at the exit ends of the sidewalls 14 act to produce a clearly
defined ending to the spray pattern.
[0012] The bed 16 includes a recess comprising a groove 21 which is aligned with the bore
8. The base 22 of the groove 21 is horizontal and is substantially level with the
lowest point of the outlet end 8b of the bore 8. The end of the groove 21 remote from
the bore 8 is closed by a (preferably vertical) step 23 which is semi-circular in
plan view. The groove 21 is of constant width and is narrower than the outlet end
8b. Adjacent the step 23, an orifice 24 communicates between the groove 21 and the
mixing space 2. Part of the water flow becomes diverted through the orifice 24 into
the container 6, causing a continuous turbulent flow in the powder, preventing the
formation of an insoluble matrix, while the powder dissolves in the water to form
a concentrated solution in the container 6.
[0013] The base member 13 includes a downwardly projecting tube 26 defining a duct 27 through
which the concentrated solution is sucked from the container 6 owing to the venturi
effect of the stream of water flowing over the upper end of the duct 27, which opens
into the upstream end of a depression 28 in the bed 16. The tube 26 depends below
the top of the container 6, thereby preventing overflow. When the cap 1 is screwed
onto the neck 4 a slight air gap is left to allow pressure equalisation in the container
6.
[0014] The duct 27 is wider than the orifice 24 and the ratio of their diameters is selected
empirically so as to achieve a desired dilution rate (weight of powder/volume of water)
without overflow from the container 6.
[0015] Between the bed 16 and the inlet section 7 the base member 13 includes a trough 29
enhancing the air break between the duct 27 and the bore 8. The trough has an optional
drainage hole 31 (or holes).
[0016] Figures 3 to 6 of the drawings illustrate a preferred embodiment of the above-described
device. Equivalent parts are denoted by the same reference numerals, and therefore
no further description is necessary. Preferred dimensions of the parts of the cap
1 are as follows. Cap 1: overall length 191.5 mm; wall 3 : outer diameter 90 mm; bore
8 : length 100 mm, inlet diameter 8.8 mm, outlet diameter 3.5 mm; bed 16 : slope 8°;
ramp 17 : radius 85.8 mm; lip 18 : height 0.57 mm, length 24.5 mm; groove 21 : width
2 mm; step 23 : height 1.5 mm; orifice 24 : upper end diameter 0.8 ± 0.1 mm, downward
divergence 4°, length 1.5 mm; duct 27 : upper end diameter 1.8 ± 0.1 mm, downward
divergence 6°, lower end 5 mm above lower edge of wall 3; depression 28 : depth 1.5
mm; trough 29 : length 5.5 mm, width 14.5 mm, depth 5 mm.
[0017] Figure 7 shows a modification of the inlet end of the inlet section 7 of the preferred
embodiment, with a manually operable on/off valve 32 for selectably turning the water
jet on and off. The valve 32 may be a sliding gate valve (as shown) or a rotary gate
valve or any other conventional type of on/off valve. The valve 32 may be incorporated
into the body of the inlet section 7, as shown, or may be provided as a fixed or removable
attachment on the spigot 9.
1. A device for entraining in a flow of water a substance contained in an open-topped
container, the device comprising a cap (1) adapted to be fitted to the open top of
the container, the cap (1) comprising a water inlet section (7) having an inlet end
(8a) which is connectable to a source of water under pressure and having a bore (8)
which communicates between the inlet end (8a) and an outlet end (8b) and which forms
the water into a jet, and a base member (13) and sidewalls (14) delimiting an upwardly
open cavity (12) into which the bore (8) discharges, the upper surface of the base
member (13) including a bed (16) which slopes upwards in the downstream direction,
the water jet impinging on the bed (16) downstream of the outlet end (8b) of the bore
(8) and flowing as a stream over the bed (16) towards an exit of the cavity (12),
the base member (13) including a hollow depending portion (26) defining a suction
duct (27) having an upper end across which the water stream flows to cause a reduction
in pressure in the suction duct (27), and including means for communicating between
the upper surface and the underside of the base member (13), the said communicating
means being upstream of the suction duct (27) and including an orifice (24) which
communicates with the underside of the base member (13) to divert water into the open-topped
container, in use characterised in that the communicating means includes a groove (21) in the bed (16), which is aligned
with the bore (8), open at the end facing the bore (8), and closed by a step (23)
at the other end, the said orifice (24) communicating with the groove (21).
2. A device as claimed in claim 1, in which the orifice (24) is nearer the said other
end of the groove (21).
3. A device as claimed in claim 2, in which the orifice (24) is adjacent to the step
(23).
4. A device as claimed in any preceding claim, in which the width of the groove (21)
at the position of the orifice (24) is substantially equal to the corresponding transverse
dimension of the orifice (24).
5. A device as claimed in any preceding claim, in which the groove (21) is narrower than
the outlet end (8b) of the bore (8).
6. A device as claimed in any preceding claim, in which the width of the groove (21)
is substantially constant along its length.
7. A device as claimed in any preceding claim, in which the base member (13) includes
an upwardly open trough (29) between the water inlet section (7) and the bed (16).
8. A device as claimed in claim 7, in which at least one drainage hole (31) communicates
between the trough (29) and the underside of the base member (13).
9. A device as claimed in any preceding claim, in which the bore (8) has a diameter which
decreases in the downstream direction.
10. A device as claimed in any preceding claim, in which the upper end of the suction
duct (27) opens into a depression (28) in the bed (16).
11. A device as claimed in any preceding claim, in which the downstream end portion of
the upper surface of the base member (13), between the suction duct (27) and the cavity
exit, includes a ramp (17) which is convex and which rises towards the cavity exit.
12. A device as claimed in any preceding claim, in which the sidewalls (14) have respective
inward projections (19) adjacent the cavity exit.
13. A device as claimed in any preceding claim, in which the base member (13) has an upwardly
projecting lip (18) adjacent the cavity exit.
14. A device as claimed in any preceding claim, in which the inlet section (7), the base
member (13), and the sidewalls (14) are constituted by a single integral moulded body
of plastics material.
15. A device as claimed in any preceding claim, in which the inlet section (7) is provided
with a valve (32) for selectably turning the water jet on and off.
1. Vorrichtung zum Mitreißen einer Substanz in einem Wasserstrom, die in einem oben offenen
Behälter enthalten ist, wobei die Vorrichtung einen Deckel (1) aufweist, der dazu
eingerichtet ist, auf die offene Oberseite des Behälters passend aufgesetzt zu werden,
der Deckel (1) einen Wassereinlaßabschnitt (7) aufweist, mit einem Einlaßende (8a),
das mit einer unter Druck stehenden Wasserquelle in Verbindung bringbar ist, und mit
einer Bohrung (8), die zwischen dem Einlaßende (8a) und einem Auslaßende (8b) eine
Verbindung herstellt und das Wasser zu einem Strahl formt, sowie ein Basisteil (13)
und Seitenwände (14), die eine nach oben offene Höhlung (12) begrenzen, in welche
die Bohrung (8) einmündet, wobei die obere Oberfläche des Basisteils (13) ein Bett
(16) aufweist, das in Strömungsrichtung nach oben geneigt ist, der Wasserstrahl auf
das Bett (16) stromabwärts vom Auslaßende (8b) der Bohrung (8) auftrifft und als Strom
über das Bett (16) zu einem Auslauf der Höhlung (12) strömt, und das Basisteil (13)
einen hohlen, abwärtsstehenden Abschnitt (26) aufweist, der eine Saugleitung (27)
bildet, die ein oberes Ende aufweist, über das der Wasserstrom quer hinwegfließt,
um eine Druckverringerung in der Saugleitung (27) zu verursachen, und mit Mitteln
für eine Verbindung der oberen Oberfläche und der Unterseite des Basisteils (13),
wobei die genannten Verbindungsmittel stromaufwärts von der Saugleitung (27) angeordnet
sind und eine Öffnung (24) aufweisen, die mit der Unterseite des Basisteils (13) in
Verbindung steht, um im Gebrauch Wasser in den oben offenen Behälter abzuleiten, dadurch
gekennzeichnet, daß die Verbindungsmittel eine Nut (21) im Bett (16) aufweisen, die
auf die Bohrung (8) ausgerichtet ist, am Ende, das der Bohrung (8) zugewandt ist,
offen ist und durch eine Stufe (23) am anderen Ende geschlossen ist, wobei die genannte
Öffnung (24) mit der Nut (21) in Verbindung steht.
2. Vorrichtung wie beansprucht in Anspruch 1, worin die Öffnung (24) dem anderen Ende
der Nut (21) nähergelegen ist.
3. Vorrichtung wie beansprucht in Anspruch 2, worin die Öffnung (24) der Stufe (23) benachbart
ist.
4. Vorrichtung wie beansprucht in jedem vorangehenden Anspruch, worin die Breite der
Nut (21) an der Stelle der Öffnung (24) im wesentlichen der entsprechenden Querabmesssung
der Öffnung (24) gleich ist.
5. Vorrichtung wie beansprucht in jedem vorangehenden Anspruch, worin die Nut (21) schmäler
ist als das Auslaßende (8b) der Bohrung (8).
6. Vorrichtung wie beansprucht in jedem vorangehenden Anspruch, worin die Breite der
Nut (21) längs ihrer Länge im wesentlichen konstant ist.
7. Vorrichtung wie beansprucht in jedem vorangehenden Anspruch, worin das Basisteil (13)
einen nach oben offenen Trog (29) zwischen dem Wassereinlaßabschnitt (7) und dem Bett
(16) aufweist.
8. Vorrichtung wie beansprucht in Anspruch 7, worin mindestens ein Drainageloch (31)
eine Verbindung zwischen dem Trog (29) und der Unterseite des Basisteils (13) herstellt.
9. Vorrichtung wie beansprucht in jedem vorangehenden Anspruch, worin die Bohrung (8)
einen Durchmesser aufweist, der sich in Stromabwärtsrichtung verkleinert.
10. Vorrichtung wie beansprucht in jedem vorangehenden Anspruch, worin sich das obere
Ende der Saugleitung (27) in eine Vertiefung (28) im Bett (16) öffnet.
11. Vorrichtung wie beansprucht in jedem vorangehenden Anspruch, worin der stromabwärts
gelegene Endabschnitt der oberen Oberfläche des Basisteils (13) zwischen der Saugleitung
(27) und dem Auslauf der Höhlung eine Rampe (17) aufweist, die konvex ist und zum
Auslauf der Höhlung hin ansteigt.
12. Vorrichtung wie beansprucht in jedem vorangehenden Anspruch, worin die Seitenwände
(14) jeweils neben dem Auslauf der Höhlung einen einwärtsgerichteten Vorsprung (19)
aufweisen.
13. Vorrichtung wie beansprucht in jedem vorangehenden Anspruch, worin das Basisteil (13)
eine nach oben vorstehende Lippe (18) neben dem Auslauf der Höhlung aufweist.
14. Vorrichtung wie beansprucht in jedem vorangehenden Anspruch, worin der Einlaßabschnitt
(7), das Basisteil (13) und die Seitenwände (14) von einem einzigen, integrierten,
abgeformten Körper aus Kunststoff gebildet sind.
15. Vorrichtung wie beansprucht in jedem vorangehenden Anspruch, worin der Einlaßabschnitt
(7) mit einem Ventil (32) versehen ist, um wahlweise den Wasserstrahl an- und auszudrehen.
1. Dispositif pour entraîner dans un courant d'eau une substance contenue dans un récipient
dont le sommet est ouvert, lequel dispositif comprend un bouchon (1) adapté pour être
emboîté sur le sommet ouvert du récipient, le bouchon (1) comprenant une section d'entrée
d'eau (7) pourvue d'une extrémité d'entrée (8a) qui peut être reliée à une source
d'eau sous pression et pourvue d'un perçage (8) qui fait communiquer l'extrémité d'entrée
(8a) avec une extrémité de sortie (8b) et qui transforme l'eau en un jet, et un élément
de base (13) et des parois latérales (14) qui délimitent une cavité (12) ouverte vers
le haut et dans laquelle le perçage (8) débouche, la surface supérieure de l'élément
de base (13) incluant un lit (16) qui présente une pente ascendante dans la direction
de l'aval, le jet d'eau heurtant le lit (16) en aval de l'extrémité de sortie (8b)
du perçage (8) et s'écoulant comme un courant sur le lit (16) en direction d'une sortie
de la cavité (12), l'élément de base (13) incluant une partie pendante creuse (26)
définissant un conduit d'aspiration (27) pourvu d'une extrémité supérieure par-dessus
laquelle le courant d'eau s'écoule afin de causer une diminution de la pression dans
le conduit d'aspiration (27), et incluant un moyen pour faire communiquer la surface
supérieure et le dessous de l'élément de base (13), ledit moyen de communication étant
situé en amont du conduit d'aspiration (27) et incluant un orifice (24) qui communique
avec le dessous de l'élément de base (13) de manière à dévier l'eau dans le récipient
à sommet ouvert, caractérisé en ce que le moyen de communication inclut une rainure
(21) dans le lit (16), laquelle rainure est alignée avec le perçage (8), ouverte à
l'extrémité située en face du perçage (8) et fermée par un gradin (23) à l'autre extrémité,
ledit orifice (24) communiquant avec la rainure (21).
2. Dispositif selon la revendication 1, dans lequel l'orifice (24) est plus près de ladite
autre extrémité de la rainure (21).
3. Dispositif selon la revendication 2, dans lequel l'orifice (24) est adjacent au gradin
(23).
4. Dispositif selon l'une quelconque des revendications précédentes, dans lequel la largeur
de la rainure (21) au niveau de la position de l'orifice (24) est sensiblement égale
à la dimension transversale correspondante de l'orifice (24).
5. Dispositif selon l'une quelconque des revendications précédentes, dans lequel la rainure
(21) est plus étroite que l'extrémité de sortie (8b) du perçage (8).
6. Dispositif selon l'une quelconque des revendications précédentes, dans lequel la largeur
de la rainure (21) est sensiblement constante sur toute sa longueur.
7. Dispositif selon l'une quelconque des revendications précédentes, dans lequel l'élément
de base (13) inclut une auge (29) ouverte vers le haut entre la section d'entrée d'eau
(7) et le lit (16).
8. Dispositif selon la revendication 7, dans lequel au moins un trou de drainage (31)
fait communiquer l'auge (29) avec le dessous de l'élément de base (13).
9. Dispositif selon l'une quelconque des revendications précédentes, dans lequel le perçage
(8) a un diamètre qui diminue en direction de l'aval.
10. Dispositif selon l'une quelconque des revendications précédentes, dans lequel l'extrémité
supérieure du conduit d'aspiration (27) s'ouvre dans une dépression (28) dans le lit
(16).
11. Dispositif selon l'une quelconque des revendications précédentes, dans lequel la partie
d'extrémité de la surface supérieure de l'élément de base (13) située du côté de l'aval,
entre le conduit d'aspiration (27) et la sortie de la cavité, inclut une rampe (17)
qui est convexe et s'élève en direction de la sortie de la cavité.
12. Dispositif selon l'une quelconque des revendications précédentes, dans lequel les
parois latérales (14) sont pourvues de saillies internes (19) respectives adjacentes
à la sortie de la cavité.
13. Dispositif selon l'une quelconque des revendications précédentes, dans lequel l'élément
de base (13) est pourvu d'une lèvre (18) saillant vers le haut, adjacente à la sortie
de la cavité.
14. Dispositif selon l'une quelconque des revendications précédentes, dans lequel la section
d'entrée (7), l'élément de base (13) et les parois latérales (14) sont constitués
par un seul corps moulé intégral en matière plastique.
15. Dispositif selon l'une quelconque des revendications précédentes, dans lequel la section
d'entrée (7) est pourvue d'une soupape (32) servant à ouvrir et fermer le jet d'eau
de manière sélective.