[0001] The present invention relates to a valve and particularly, but not exclusively, to
a valve for a tap for dispensing beverages under pressure from containers.
[0002] In such taps at the present time beverage flow is controlled by means of a spring
loaded valve. This generally comprises an elongate axially movable valve member disposed
in a valve housing defining an inlet and an outlet. The member defines a groove which
accommodates an '0' ring at one end and supports a coaxially arranged spring. The
spring urges the elongate valve member, and through it, the '0' ring against a frusto-conical
valve seat to seal off the fluid flow passage from the inlet to the outlet. Many of
the beverages.dispensed have an inherent stickiness and this tends to cause the '0'
ring to adhere to the valve seat so that, particularly after a period of non-use the
'0' ring is displaced from its accommodating groove when the tap is next operated.
Beverages may also have a deleterious effect on the'spring eventually reducing its
efficiency and impeding its return action. Both of these faults lead to valve leakages
which in turn leads to losses and expense and often to unsightly staining of equipment.
An object of the present invention is to alleviate or eliminate these disadvantages.
[0003] According to the present invention there is provided a fluid flow valve comprising
a valve housing defining a valve seat, an inlet leading into the valve housing, an
outlet leading from the valve housing, a resiliently deformable valve member disposed
in the valve housing and adapted to coact with the valve seat, and means for deforming
the valve member to displace it from a first position in which it abuts the valve
seat to prevent fluid flow from the inlet to the outlet to a second position in which
it permits fluid flow from the inlet to the outlet.
[0004] A preferred embodiment of the invention may comprise any one of more of the following
advantageous features:-
(a) The valve member is moulded from a natural resilient material such as rubber.
(b) The valve member is moulded from a synthetic plastics material such as neoprene.
(c) The valve member is hollow and partially accommodates the means for deforming.
(d) The means for deforming comprises an actuation member extending out of the valve
member and connected to an actuation mechanism.
(e) The actuation mechanism comprises a cam operative to lift the actuation member
to deform the valve member to displace it from the valve seat.
(f) The cam comprises one or more projections which seat in corresponding recesses
in the non operative, closed position of the valve and which are lifted therefrom
in the operative open position of the valve.
(g) The valve seat is frusto-conical and the valve member is complementary in shape
to it.
[0005] In order that the invention may be more clearly understood, one embodiment thereof
will now be described, by way of example, with reference to the accompanying drawings,
in which:-
Figure 1 shows a side elevational view in partial section of a beverage dispensing
tap incorporating a-valve according to-the invention, and
Figure 2 is a partial front elevational view in section of a part of the tap of Figure
1.
[0006] Referring to Figure 1, the tap generally comprises an inlet duct 1, an outlet duct
2, a valve 3 disposed between ducts 1 and 2 and a valve actuation mechanism 4. The
duct 1 comprises a threaded connector 5 for connection to a beverage source and the
duct 2 an adjustable dispensing cap 6 for altering the envelope of the beverage spray
which emanates therefrom in use of the tap.
[0007] The valve 3 comprises a valve housing 7 defining a valve chamber 8 which communicates
via a duct la with the duct 1 and which incorporates a frusto-conical valve seat 9.
A valve member 10 is disposed in the valve chamber 8 and seats at its lower, frusto-conical,
end on'the valve seat in the closed position of the valve. The valve member 10 is
composed of a resiliently deformable material such as neoprene and itself defines
an internal chamber or bore 11. This chamber 11 partially accommodates a valve actuating
rod 12. The rod 12 has a head 13 at one end which is set and held in the neoprene
and at its other end extends out of the chamber 11 into the valve actuating mechanism
4. The upper end of the valve member 10 is formed with a shoulder 14 which abuts a
substantially complementary shoulder formed in the wall of the valve chamber 8.
[0008] A further externally screwthreaded spacer 17 is screwed into the complementary internally
screwthreaded upper end of the valve chamber 8 to abut and bear down on the valve
member 10 and push it against the valve seat 9.
[0009] The valve actuating mechanism, which is connected .to the actuating rod 12, is disposed
above the spacer 17. This mechanism comprises a hollow cylindrical member 18 which
provides a cam surface and is keyed at 18a into the internal surface of the valve
housing 7, a cam 19 and an operating lever 20. The keying 18a prevents relative rotational
movement between but permits relative axial movement between the member 18 and housing
7. The lever 20 is connected to the cam 19 and the rod 12, which extends through the
cam 19, is screwthreaded at its upper end, and retained in position by a nut 22. Two
coil springs 15 and 16 respectively are constrained to act between the spacer 17 and
member 18 and between the spacer 17 and between the head 13 of the rod 12. Spring
15 urges member 18 against cam 19. Spring 16 urges rod 12 down towards the valve seat'9.
[0010] The.operative parts of the cam 19 are two projections 23 (see Figure 2) of V-shaped
cross-section which seat in complementary V-shaped recesses in the upper surface of
the member 18. To operate the valve the lever 20 is turned through a small angle either
into or out of the plane of the drawing of Figure 1. The rotational movement withdraws
the projections 23 out of their recesses thus lifting cam 19 and the rod 12 relative
to the member 18. This upward movement of the rod 12 distorts the valve member 10
thus lifting its lower part away from the valve seat 9 and allowing beverage to pass
from the inlet duct 1, through the duct la down through the valve chamber 8 and out
through the outlet duct 2. Returning the lever to the off position enables the rod
12 and the member 10 to return to their normal rest position under the action of the
natural resilience of the member 10 assisted by the spring 16.
[0011] In a preferred arrangement of the tap, the tap lever is spring loaded so that when
turned in one direction to operate it, it returns automatically to the off position
on release and when turned in the opposite direction it remains in the on position
until positively returned to the off position.
[0012] It will be appreciated that the relatively large sealing area between tie valve member
and the valve seat tends to overcome any disadvantages previously associated with
'0' ring sealing. Also, employing the natural resilience of the valve member material
can enable a-spring return to be eliminated. Even when springs 15 and 16 are incorporated,
they are not brought into contact with the beverage. Other modifications, within the
scope of the invention are also possible.
1. A fluid flow valve comprising a valve housing (7) defining a valve seat (9), an
inlet (1) leading into the valve housing, an outlet (2) leading from the valve housing
(7), characterised by a resiliently deformable valve member (10) disposed in the valve
housing (7) and adapted to coact with the valve seat (9), and means (4, 12) for deforming
the valve member to displace it from a first position in which it abuts the valve
seat (9) to prevent fluid flow from the inlet (1) to the outlet (2) to a second position
in which it permits fluid flow from the inlet (1) to the outlet (2).
2. A fluid flow valve as claimed in Claim 1, in which the valve member (10) is moulded
from a natural resilient material such as rubber.
3. A fluid flow valve as claimed in Claim 1, in which the valve member (10) is moulded
from a synthetic plastics material such as neoprene.
4. A fluid flow valve as claimed in Claim 1, 2 or 3, in which the valve member (10)
is hollow and partially accommodates the means for deforming (4, 12).
5. A fluid flow valve as claimed in Claim 1, 2, 3 or 4, in which the means for deforming
(4, 12) comprises an actuation member (12) extending out of the valve member (10)
and connected to an actuation mechanism(4).
6. A fluid flow valve as claimed in Claim 5, in which the actuation mech anism(4)
comprises a cam operative (19) to lift the actuation member (12) to deform the valve
member (10) to displace it from the valve seat (9).
7. A fluid flow valve as claimed in Claim 6, in which the cam (19) comprises one or
more projections (23) which seat in corresponding recesses in the non operative, closed
position of the valve and which are lifted therefrom in the operative open position
of the valve.
8. A fluid flow valve as claimed in any preceding claim, in which the valve seat (9)
is frusto-conical and the valve member (10) is complementary in shape to it.