IMPROVEMENTS IN OR RELATING TO DIP TUBES
The present invention relates to improvements in or relating to dip tubes
for use in pressurised and non-pressurised containers to permit fluid to be
drawn to, and dispensed through, an outlet of the container during use.
Nozzle arrangements are often fitted to, or over, the outlet valves of
pressurised fluid filled containers, such as, for example, a hand-held aerosol
canister. Such nozzle arrangements typically comprise an actuator portion that
can be depressed by an operator to cause the outlet valve of the container to
open and thereby actuate the release of fluid stored in the container through the
nozzle arrangement. Similarly, nozzle arrangements provided with a manually
operable pump or trigger actuator which operates a pump chamber in order to
cause fluid to be dispensed through the nozzle arrangement (hereinafter
referred to as "pump or trigger actuated nozzle arrangements" or just "pump or
trigger nozzle arrangements") are also widely used in conjunction with non-
pressurised containers. Pump or trigger-actuated nozzle arrangements are fitted
to an outlet opening of the container, typically by means of a screw thread, and
enable a fluid present in the container to be dispensed through the nozzle
arrangement by the operation of the pump or trigger actuator.
The fluid products stored in containers are usually various forms of
liquid and, to enable the liquid product stored in the container to be drawn to,
and dispensed through, a nozzle arrangement during use, it is known to provide
a dip tube positioned inside the container. A typical dip tube has a free or open
end disposed proximate to the bottom of the container and an opposing end
which is typically connected to the outlet valve (in the case of pressurised
containers) or directly to the pump or trigger actuated nozzle arrangement (in
the case of non-pressurised containers). During use, i.e. following the
operation of the actuator of the nozzle arrangement, the liquid product is drawn
into the dip tube from the bottom of the container through its free/open end, and
along the dip tube to the outlet valve of the container, or the pump or trigger
actuated nozzle arrangement (in the case of non-pressurised containers) where
it is dispensed from the container.
These conventional dip tubes function well if the liquid is being
dispensed while the container is upright. This is because the free/open end of
the dip tube is positioned at the bottom of the container where it is immersed in
the liquid product and will remain so until all, or nearly all, of the product had
been dispensed. However, problems can arise when the container is inverted or
tilted during use because the liquid product present is the container will flow
towards the inverted or tilted upper end of the container under the influence of
gravity and this may leave the free end of the dip tube extending into an upper
fraction of gas (which may be air at atmospheric pressure in the case of a non-
pressurised container, or compressed air or an alternative gaseous propellant in
the case of a pressurised container). As a consequence, the operation of the
nozzle while the container is inverted or tilted can result in the expulsion of this
gas rather than the liquid product stored in the container. This creates a
problem because it disrupts the dispensing of the desired liquid product.
Furthermore, it is a particular problem when the container is a pressurised
container and compressed air or gas is used as the propellant because the
expulsion of this air or gas instead of the liquid product results in the depletion
of the propellant from the container. Ultimately this can result in the
exhaustion of the propellant before all the product present in the container has
been dispensed, which is clearly undesirable.
For these reasons, it is an object of the present invention to provide a
simple and inexpensive means for enabling a liquid product stored within a
container to be dispensed continuously through a nozzle arrangement fitted to
an outlet of the container, even if the container is held at an angle where the
open end of the dip tube is not usually immersed in the product (i.e. when it is
shaken, tilted or inverted), or when the product is product stored in the
container is nearly exhausted.
It is a further object of the present invention to provide a device,
container and modified dip tube in which the expulsion of gas or air instead of
product is minimised while the container is inverted, shaken or held at a tilted
orientation.
According to a first aspect of the present invention there is provided a
device adapted to be placed inside a container and to permit a liquid stored in
said container to be drawn from the interior of the container into said device
and from said device to the outlet of the container where it is dispensed through
a nozzle arrangement, said device having a body which defines an internal
chamber, an inlet through which liquid may be drawn into said chamber, and an
outlet through which liquid can be drawn out of said chamber;
wherein said inlet is adapted to at least restrict the access of liquid to
said chamber at least when said device is inverted from an upright position.
The expression "upright position" is used herein to denote an orientation
which the device assumes when it is suspended in a container by its outlet and
can hang freely. In preferred embodiments of the invention the outlet is
positioned on the upper surface of the device and the inlet is positioned on the
bottom of the device. Hence, the upright position in such cases will be the
orientation assumed by the device when it is suspended by its outlet and hangs
freely with the inlet forming the bottom or lowermost part of the device.
Preferably, the inlet is further adapted to at least restrict the access of
liquid when said device is tilted or shaken.
By "tilted", we mean that the device is displaced from the upright
position, but is not full inverted, i.e. it orientation is some where between a
fully upright or fully inverted position.
It is especially preferable that the inlet is adapted to at least restrict
access to said chamber when said device is tilted so that the inlet is no longer
immersed within liquid present within said container.
In certain embodiments of the invention, the device is adapted to at least
restrict access to the chamber when the device is titled through ninety degrees
or more from the upright position.
It has been found that the utilisation of the device of the present
invention circumvents, or at least minimises, the problem of gas or air being
dispensed through the outlet of the container instead of the product when the
device is inverted or tilted so that the inlet is not immersed in the product
present in the container. Specifically, the chamber of the device enables a
reservoir of the product present the container to be stored witliin the device.
This reservoir of product is available for dispensing regardless of the
orientation of the device (and hence, the container in which it is placed).
Furthermore, the provision of an inlet which is adapted to restrict access to the
chamber at least when the device is inverted or held at a tilted angle where the
inlet is not immersed in the product prevents, or at least minimises, the volume
of gas or air that can be drawn into the device and, ultimately, dispensed
through the nozzle arrangement during use. Accordingly, an operator using a
container with the device of the present invention placed inside will not notice
any significant difference in the quantity of product dispensed through the
outlet when the container if it is operated while the container is inverted,
upright, shaken or held at a tilted orientation.
The device of the present invention may be placed within any suitable
container which is provided with a nozzle arrangement to actuate and control
the release of the product stored in the container. It shall be appreciated,
therefore, that the container may be a non-pressurised container which is
provided with a pump or trigger-actuated nozzle arrangement fitted to its outlet.
In such cases, the outlet of the device is usually connected to the nozzle
arrangement so that liquid drawn through the device during use passes directly
into the nozzle arrangement when the trigger or pump actuator is operated.
Alternatively, the container may be a pressurised container provided with a
valve at its outlet (hereinafter referred to as an outlet valve) having a nozzle
arrangement fitted to the container which has an actuator adapted to releasably
engage with the outlet valve to open it and actuate the release of the liquid'
product stored in the contamer. In this case, the outlet of the device is adapted
to be connected to the internal surface of the so that, when the outlet valve is
open, liquid is drawn to the outlet valve through the device of the present of the
invention. In some cases the propellant present in the pressurised container will
be a compressed gas, such as compressed air, which is a particularly desirable
propellant to use.
The chamber of the device may be prepared from a rigid material. For
example, the wall of the chamber may be in the form of a bellows, which can
collapse inwards to reduce the volume of the chamber when fluid is drawn out
of the chamber through the outlet faster than it is replenished through the inlet
during use, and then return to its original non-deformed configuration and
thereby cause liquid to be drawn into the chamber through the inlet. Preferably,
however, at least a portion of said body forming a wall of said chamber is
resiliently deformable and configured to assume a resiliently biased or "non-
deformed" configuration in the absence of any pressure differential between the
chamber and the external environment and deform inwards to a collapsed
configuration and thereby reduce the volume of the chamber when the pressure
within the chamber is lower than the external pressure. This enables the
resiliently de ormable portion of the wall of the chamber to deform inwards and
cause the volume of the chamber to decrease as product is drawn out of the
chamber during use and subsequently return to its original resiliently biased
configuration and drawn in more liquid through the inlet. It is especially
preferred that the entire wall of the chamber is resiliently deformable. Most
preferably, the entire body of the chamber is resiliently deformable.
Any suitable resiliently deformable material may be used, such as a
flexible rubber or flexible plastic material (e.g. flexible polyethylene of
polypropylene compositions).
The device of the present invention may be readily manufactured by
conventional moulding techniques and as such are relatively inexpensive to
produce.
Prior to its initial insertion into the container, it is preferable to crush the
device so that, once it is placed inside the container, it will return to its original
"non-deformed" configuration and, in doing so, will draw the product from the
container into the chamber of the device ready for use. The body may be
pleated to enhance the crushing of the device.
Preferably, when the device is placed in a container, the inlet of the
device is adapted to be positioned proximate to the bottom of the container in a
similar manner to the opening of a standard dip tube. This results in fluid being
drawn into the device from the bottom of the container and enables virtually all
of the product stored in the container to be drawn into the device and dispensed
through the nozzle arrangement.
The inlet of the device is adapted to restrict access to the chamber at
least when the device is inverted from an upright position during use (i.e. when
the container in which it is placed is inverted). It shall be appreciated that the
opening of the inlet will invariably become exposed to the gas fraction present
in the container when it is tilted or inverted, and hence, the inlet serves to
restrict the amount of gas that may access the device and thus, be expelled
through the nozzle arrangement under these circumstances.
In its simplest form the inlet of the device comprises a constricted
opening. By "constricted opening" we mean that the opening defined by the
inlet has a maximum dimension which is less than that of the outlet of the
device so that the flow into the chamber through the inlet is less than the flow
which is possible through the outlet. In some embodiments, the inlet will be a
fine hole formed in the wall of ύie chamber. In other embodiments, the inlet of
the device may comprise a tube which is open to the chamber at one end and
the constricted opening may be disposed at any position along the length of the
tube. The constricted opening impedes the flow of gas or air into the device
when the container is inverted or tilted so that the inlet is not immersed in any
liquid present in the container. Preferably, the constricted opening reduces the
flow through the inlet to between 0 and 20% of the flow which is possible
through the outlet. More preferably, the constricted inlet is adapted to restrict
the flow through the inlet to between 1 and 10% of the flow which is possible
through the outlet. Most preferably, the constricted inlet is adapted to restrict
the flow through the inlet to between 5 and 10% of the flow which is possible
through the outlet. This is achieved by controlling the relative sizes of the
constricted inlet opening and the outlet, i.e. it is preferable that the inlet is
between 1 and 20%, more preferably 1 and 10%, and most preferably 5 and
10%, of the size of the outlet. Accordingly, when the liquid is being dispensed
through the container it is usually drawn from the reservoir held within the
chamber of the device faster than it can be replaced with either more product
present in the container (if the inlet opening is immersed in the product) or gas
or air (if the product is inclined at an angle where the inlet is not immersed in
the product). In preferred embodiments where the chamber has a resiliently
deformable wall, the wall will deform inwards and the volume of the chamber
will reduce if the product is dispensed through the outlet of the chamber at a
rate which is faster than it is replenished by the contents of the container
through the inlet. Once the release of fluid from the container ceases, the
container, and hence the device placed therein, will usually be returned to its
upright position in which the inlet will be immersed in the liquid stored in the
container. As the chamber deforms back to its resiliently biased configuration,
liquid from the container will be drawn into the chamber of the device through
the inlet. Although a proportion of the gas present in the container may still
access the chamber of the device if the inlet is not immersed in the product, i.e.
if the device is tilted, shaken or inverted, the provision of a reservoir of product
at least ensures that a proportion of the product will be dispensed and the
provision of the constricted opening ensures that the amount of gas expelled
through the outlet will be significantly reduced when compared with a standard
dip tube.
It is preferred, however, that the inlet comprises a valve which is adapted
to close off the inlet to form at least a partial seal when the device is inverted or
tilted through 90 degrees or more from the upright position, and open the inlet
when the device is placed in the upright position (when the inlet is normally
immersed in the product at the bottom of the container).
Preferably, the valve is adapted to completely seal the inlet when the
device is inverted or tilted through 90 degrees or more from the upright
position.
Any suitable valve may be used. Preferably, the valve comprises a
cavity defined by the inlet, said cavity having a ball (e.g. a ball bearing) or other
moveable body retained therein and being configured such that said ball or
other moveable body occupies a first position within the cavity when said
device is upright and becomes displaced to a second position when said device
is inverted or tilted, whereby said valve is open when said ball or other
moveable body is in the first position and said valve at least partially closed
when said ball or other moveable body is in the second position. Usually, the
first position is a lower position and said second position is an upper position
and said ball or other body moves between said lower and upper positions by
the effect of gravity.
Preferably, the valve is completely closed when the ball or other
moveable body is in the second position.
Accordingly, when the container and the device are upright, the ball
bearing resides in the first or lower position in the cavity defined by the inlet
and the actuation of the release of the contents of the container by the operation
of a nozzle at the outlet of the container results in product being drawn into the
device through the inlet and passing through the chamber and the outlet of the
device into the nozzle arrangement. In effect, the device functions just like a
standard dip tube in this position. However, when the device is inverted, or
tilted through 90 degrees or more from the upright position so as to cause the
movement of the ball bearing or similar structure to the second/upper position
within the cavity under the influence of gravity and thereby form a seal in the
inlet, then the influx of liquid product or gas/air (depending whether or not the
inlet is immersed in the liquid product) is restricted.
The provision of a partial or complete seal of the inlet will result in
liquid being expelled through the outlet of the chamber of the device at a
greater rate than the rate at which the contents of the container are drawn into
the chamber through the inlet. Hence, in embodiments where the chamber has
a resiliently deformable wall, this will cause the resiliently deformable wall to
be sucked inwards, effectively reducing the internal volume of the chamber.
Once actuation of the release of the product is terminated by stopping the
operation of the nozzle arrangement, then the elastic recoil forces present in the
resiliently deformed walls of the chamber will create a vacuum pressure within
the chamber which in turn generates a suction force in the inlet to the device.
This suction force can cause the ball or similar body to be retained in the
second/upper position once the device is returned to its upright standing
position. For this reason, it is also preferable that the valve is provided with
means to dislodge the ball or other moveable body from the second position
back to the first position when said device is returned to the upright position.
In certain embodiments of the invention, the means for dislodging the
ball is the provision of a partial seal when the ball or other moveable body is in
the second position. This permits a degree of leakage to occur around the ball
or body and enables contents of the container (which is usually product if the
container is stood upright and the inlet is immersed in the product) to access the
chamber of the device to equalise any pressure differential that may exist.
Hence, once the suction force has been removed, the ball or other body will
become dislodged from the second position. The pressure differential will
usually be equalised once the resilientiy deformable wall of the chamber has
retained it original non-deformed or resiliently biased configuration.
Preferably, the amount of leakage through the partial seal is between 1
and 20% of the flow possible through the outlet of the device. Most preferably,
the amount of leakage through the partial seal is between 5 and 20% of the flow
possible through the outlet of the device.
If the partial seal is only weak then the ball or other body could be
dislodged to the first position by simply shaking the device/container, or it may
just drop back to the first position by the effect of gravity.
The provision of a partial seal may be preferable when the product
contained within the container is a product that is likely to block or clog the
valve during use. Examples of such products include various polishes, paints,
starches etc. The recess comprising the ball bearing is much less likely to block
or clog during use and every time the ball bearing moves any residue that has
built up and will become dislodged.
Alternatively, the means for dislodging the ball or other moveable body
may be a leak provided in some other part of the device.
The ball valve may also be provided with an alternative means for
ensuring that the ball is dislodged when the device is returned to the upright
position after use at a tilted/inverted angle. One example of such a means
involves the provision of a small protrusion or post in the internal wall of the
valve of the device which, when the ball is in the upper position, either pushes
the ball away (towards the lower position) or pushes between the ball and the
internal wall of the valve as the chamber/device collapses during use.
Alternatively, the device may be configured so that once it is virtually
empty the deformation caused in the device either pushes the ball out from the
partial seal position or deforms the valve in the vicinity of the ball so that it can
fall back to its original position in which the valve is open under the influence
of gravity.
If the inlet is either in the form of a constricted opening or comprises a
valve capable of forming only a partial seal, it is possible that a small amount of
gas may access the device when the container is inverted, tilted or shaken,
although it will still be significantly less than if the partial seal was not formed.
For example, if an aerosol canister can spray 1 millilitre/second through its
outlet and is usually used for between 3 and 5 seconds per actuation, then it will
be possible for gas to be expelled through the outlet at the same rate when the
dip tube is not immersed in the product. However, if the inlet is adapted to
restrict access to the chamber when the container is tilted or inverted to, for
example, only 10% of that which is possible through the outlet of the device,
then the amount of gas that can be ejected through the outlet of the container
during actuation is only 0.1 millimetres/second, i.e. the amount of gas that
could be ejected through the nozzle is effectively reduced by 90%. In practice,
the actual amount of gas expelled through the outlet in preferred embodiments
of the invention where the entire device is formed from a flexible material will
be much less because, by virtue of the weight of the liquid present in the
chamber, the device will tend to remain immersed in the liquid product present
in the container, especially when the container is only tilted slightly from the
upright position. For example, if the container is placed on its side, then the
device will tend to float on the surface of the liquid product and the weight of
the liquid present in the device tends to cause the lower inlet end to be
submerged in the liquid.
However, as previously mentioned, it is especially preferred that the
valve forms a complete seal to prevent any gas or air being expelled when the
container is tilted or inverted.
In addition to, or instead of, either of these aforementioned forms of
inlet, an alternative valve could be provided at the inlet. A suitable example of
one such additional valve is a so-called "flap valve". It is especially preferred
that the flap of said valve is weighted and adapted to move under the influence
of gravity between an initial position in which the valve is open when the
device is upright and a position in which the valve is closed when the device is
inverted or tilted. In certain preferred embodiments of the invention the inlet is
a tube and the open end of said tube through which fluid accesses the tube
during use forms the weighted flap which is adapted to hang downwards when
the device is upright so at to form an open tube and fold over when the device
is inverted so as to form a kink at a position along the length of the inlet tube
when the device is inverted or tilted, said kink forming at least a partial seal to
prevent or minimise the ingress of fluid into the device while it is inverted or
tilted. Effectively, the weighted end of the tube is adapted to fall over and form
a kink in the inverted inlet tube to form a seal in the tube when the device is
inverted, and fall back to form an open tube when the device is returned to the
upright position. It is preferable that a complete seal is formed by the kink in
the inlet tube, rather than just a partial seal.
The outlet of the device may enable the product to be drawn from the
bottom or the top of the chamber of the device when the container (and hence,
the device) is in the upright position. In some embodiments of the invention
the outlet of the device is an opening in the chamber wall that can receive a dip
tube which connects the chamber of the device with the outlet of the container.
In other embodiments, the outlet is an open end of an outlet tube, which is
integrally formed with the device, and is open to the chamber at one end and
connected to the container outlet at the other end.
In certain preferred embodiments of the invention, the body of the
device may define two or more separate chambers. A first chamber of said
chambers will be as defined above and possess the inlet and outlet, whereas a
second of said chambers will posses an outlet. The second chamber may just
have an outlet or may further comprise an inlet so that fluid may be drawn into
the second chamber. It is generally preferred that the second chamber is a
sealed chamber only having an outlet and a fluid product, which may be a
liquid or a gas, can be placed in the second chamber and drawn out through its
outlet in a similar manner to the way fluid is drawn from the first chamber. The
outlets of the first and second chambers may join so that the fluid drawn out of
each chamber mix with each other before reaching the outlet valve or nozzle
arrangement of the container. Alternatively, the outlets of each chamber may
be separate and each outlet may form a separate connection with the outlet
valve or pump or trigger nozzle arrangement. In the case of pressurised
containers, the fluid from each chamber may mix within the outlet valve or
within a nozzle arrangement fitted to thereto. In the case of non-pressurised
containers, the contents of each chamber may be mixed within the pump or
trigger actuated nozzle arrangement. Alternatively, the fluids may be ejected
separately from the nozzle arrangements.
The dimensions of the outlets of said first and second chambers can be
modified to control the relative rates at which fluid is drawn from each
chamber.
The two or more chambers of the device may be separate, adjacent to
one another or arranged in any other suitable configuration. In a preferred
embodiment of the invention a first chamber is surrounded by a second
chamber in a concentric arrangement.
In situations where the device is placed in a pressurised container, such
as hand-held aerosol canister, it is desirable for the second chamber to contain a
propellant in certain cases. The propellant can mix with the liquid drawn from
the first chamber and can assist the atomisation of the liquid into small droplets.
In such cases, it may be preferable to provide a constricted opening, such as a
fine hole, in the wall of the device so that gas present in the container can be
slowly drawn into the second chamber from the container when it is in the
upright position (i.e. the opening must be positioned above the hquid level in
the upright position). This will enable the propellant depleted from the second
chamber during use to be replenished with more propellant from the interior of
the container.
In certain embodiments of the invention, the chamber is. divided into two
separate compartments, an upper compartment and a lower compartment, with a
hole formed in the interface between them. Preferably, the hole formed in the
interface is sufficiently small to restrict the movement of the contents of the
chamber between the upper and lower compartments when the container (and
hence, the device) is inverted. It is also preferable that the lower compartment
is three to four times the size of the upper compartment. In such embodiments,
it also preferred that the inlet of the device is a tube which opens into the upper
chamber of the device so that the contents of the container that are drawn into
the chamber through the inlet initially access the upper chamber. It is also
preferred that the outlet of the device is a tube which is open to the chamber at
the bottom of the lower compartment and extends upwards from the device to
form a connection with the outlet of the container. Preferably, the outlet tube is
provided with a hole positioned approximately half way up the chamber, which
connects the interior of the chamber to a position along the length of the outlet
tube. The significance of this hole is discussed further below in reference to
Figure 1 of the accompanying drawings.
The device of the present invention can be placed inside a container
instead of, or as an attachment to, a standard dip tube. Accordingly, the present
invention also provides, in a further aspect, a dip tube comprising a device as
defined herein fitted thereto.
Preferably, however, the device is fitted to the end of the dip tube via its
outlet, i.e. the dip tube forms the connection between the chamber outlet and
the outlet of the container. Where this is the case, the outlet of the device may
be in the form of a tube which connects to the end of the dip tube or,
alternatively, an opening in the chamber which is adapted to receive the end of
the dip tube. Alternatively, the device may be connected directly to the
container outlet and the dip tube may be connected to the inlet of the device.
According to a further aspect of the present invention there is provided a
pressurised container having an interior in which a liquid may be stored, an
outlet valve, a nozzle arrangement having an actuator adapted to selectively
engage and open said outlet valve upon operation and thereby actuate the
release of liquid under pressure, wherein said container comprises a device as
defined herein placed therein and fitted to said outlet valve via its outlet so that
fluid is drawn from said device when said actuator of said nozzle arrangement
is operated.
According to a further aspect of the present invention there is provided a
pressurised container having an interior in which a liquid may be stored, an
outlet valve, a nozzle arrangement having an actuator adapted to selectively
engage and open said outlet valve upon operation and thereby actuate the
release of liquid stored therein under pressure, wherein said container
comprises a dip tube as defined herein placed therein and fitted to said outlet
valve so that fluid is drawn from said dip tube when said actuator of said nozzle
arrangement is operated.
According to a further aspect there is provided a non-pressurised
container having an interior in which a liquid may be stored, an outlet having a
pump or trigger actuated nozzle arrangement fitted thereto and comprising a
device as defined herein placed therein, said device being connected to said
nozzle arrangement via its outlet such that liquid is drawn into said nozzle
, arrangement from said device when the trigger or pump actuator is operated.
According to a further aspect of the present invention there is provided a
non-pressurised container having an interior in which a liquid may be stored, an
outlet having a pump or trigger actuated nozzle arrangement fitted thereto and
comprising a dip tube as defined herein placed therein, said dip tube being
connected to said nozzle arrangement via its outlet such that liquid is drawn
into said nozzle from said dip tube when the trigger or pump actuator is
operated.
According to a further aspect the present invention there is provided a
container having an interior in which liquid may be stored, an outlet having a
nozzle arrangement fitted thereto and a device placed in the interior of the
container, said device being adapted to permit a liquid stored in said container
to be drawn from the interior of the container into said device and from said
device to the outlet of the container where it is dispensed through a nozzle
arrangement, said device having a body which defines an internal chamber, an
inlet through which liquid may be drawn into said chamber, and an outlet
through which liquid can be drawn out of said chamber;
wherein said device is suspended in said container by its outlet so that it
can swing within the container as it is tilted or inverted.
Preferably, the device is as defined above.
The suspension of the device permits the device to swing within the
container. Therefore, the device, by virtue of the weight of the liquid present in
the chamber, will tend to remain immersed in any hquid product present in the
container, especially when the container is only tilted slightly from the upright
position. For example, if the container is placed on its side, then the device will
tend to float on the surface of the liquid product and the weight of the liquid
present in the device tends to cause the lower inlet end to be submerged in the
liquid.
According to a further aspect the present invention there is provided a
pressurised container having a sealed interior, an outlet valve, an internal wall
defining an internal compartment positioned at or proximate to the bottom of
the interior of said container and a dip tube positioned within the interior of
said container, said dip tube being connected to said outlet valve and extending
from said valve to said internal compartment such that fluid is drawn to said
outlet valve from said compartment when the outlet valve is opened, wherein
said compartment further comprises an inlet through which fluid can access
said compartment from the interior of the container, said inlet being further
adapted to at least restrict the access to said compartment when said container
is inverted.
According to a further aspect the present invention provides a non-
pressurised container having an interior, an outlet with a pump or trigger
actuated nozzle arrangement fitted thereto, an internal wall defining an internal
compartment positioned at or proximate to the bottom of the container and a dip
tube extending from said nozzle arrangement into said internal compartment
such that fluid is drawn to said nozzle arrangement from said compartment
when the pump or trigger actuator is operated, wherein said compartment
further comprises an inlet through which fluid can access said compartment
from the interior of the container, said inlet being further adapted to at least
restrict the access to said compartment when said container is inverted.
The inlet may comprise a constricted opening or a valve, as defined
above.
In a preferred embodiment, the inlet comprises a constricted opening
formed around the dip tube where it extends into the compartment. The
contents of the container may flow slowly from the remainder of the container
into the compartment through this constricted opening. Preferably, the rate of
flow is between 5 and 20% of the rate of flow through the dip tube.
The inlet is preferably positioned so that it is immersed in any liquid
present in the container while the container is stood in its upright position.
Preferably, at least a portion of said internal wall defining said internal
compartment is resiliently deformable and configured to assume a resiliently
biased configuration in the absence of any pressure differential between the
compartment and the interior of the container and deform inwards and reduce
the volume of the compartment when the pressure within the compartment is
lower than the pressure in the interior of the chamber. Most preferably, the
entire internal wall of the chamber is resiliently deformable. The resiliently
deformable wall may be made of any suitable resiliently deformable material,
as described above.
The compartment may be formed across the entire bottom of the
container or just a portion thereof. It is especially preferred that the
compartment extends across the entire bottom of the interior of the container
and the internal wall forms the bottom or floor of the remainder of the interior
of the container.
During use, the contents of the compartment are drawn to the outlet
through the dip tube during use in response to the opening of the outlet valve
or, in the case of a non-pressurised container, the operation of the pump or
trigger of the nozzle arrangement. As the contents of the compartment are
drawn into the dip tube, the resiliently deformable wall will deform inwards,
effectively reducing the volume of the compartment, because the rate at which
the product is replenished with the contents of the container will be less than
that rate at which it is drawn out through the dip tube. After use, the container
is returned to the upright position and liquid is then drawn into the
compartment from the interior of the container to through the inlet. This
replenishment will continue until the resiliently deformable wall returns to its
initial resiliently biased or "non-deformed" configuration.
If the container is tilted, shaken or inverted, then liquid will still be
dispensed through the outlet during use because the liquid present in the
compartment is prevented from leaking out into the remainder of the container
to any significant degree by the constricted opening. Furthermore, the influx of
any gas or air from the container into the compartment while the container is
tilted, inverted or shaken (and the inlet of the compartment is not immersed in
the product present in the container) is also rninimised by the constricted
opening.
The container may comprise two or more internal compartments. Each
compartment may be provided with a separate dip tube or receive a branch of a
single dip tube.
It has also been found that the problem of maintaining the continuous
release of product from a container when it is shaken or held at an angle where
the open end of the dip tube is not immersed in the product can also be
minimised by using a modified dip tube.
Hence, the present invention also provides, in a further aspect, a
container having an interior in which a liquid may be stored during use, said
container comprising an outlet having a manually-operable pump or trigger
actuated nozzle arrangement fitted thereto and a dip tube positioned in the
interior of said container, said dip tube having an inlet end through which fluid
present in the container may access the dip tube and an opposing end which is
connected to the nozzle arrangement so that liquid stored in the container can
be drawn to, and dispensed through, the nozzle arrangement following the
operation of the pump or trigger, wherein the internal volume of the dip tube is
at least five times the volume of product that is dispensed through the nozzle
arrangement following a single full actuation.
It shall be appreciated that by "full actuation" we mean that trigger or
pump of the nozzle device is actuated to its maximum extent so that the
maximum possible volume of product is dispensed through the nozzle in
response to a single actuation.
Conventional dip tubes fitted to pump or trigger nozzle devices typically
have an internal volume that is, at most, only one to two times the volume that
is dispensed through a pump or trigger nozzle following a single full actuation.
This low internal volume is specif ically desired by manufacturers of pump and
trigger spray devices because it reduces the number of actuations of the pump
or trigger required to initially fill the dip tube before the liquid product can be
dispensed through the nozzle. As a consequence, however, only a limited
volume of Hquid product can be retained within the dip tube and this will be
rapidly exhausted if the nozzle device is operated while the container is held at
an angle where the open end of the dip tube through which the contents of the
container are drawn is not immersed in the product present in the container, i.e.
if the nozzle device is actuated while the container is shaken, inverted or tilted.
However, it has been found that providing a dip tube with a volume that is at
least five times the volume dispensed through the nozzle device following a
single full actuation enables the product to be dispensed through the nozzle for
longer periods when the open end of the dip tube is not immersed in the
product.
It will be appreciated that if the container remains inverted, for example,
then ah present in the container will eventually be ejected through the nozzle
instead of product once the product stored in the dip tube has been exhausted.
For this reason, the intemal volume of the dip tube is preferably sufficient to
store enough of the product therein to enable above average usage of the
product concerned. Hence, the volume required will vary depending on the
type and nature of the product, but it should be at least five times the volume of
product which is dispensed through the nozzle following a single full actuation
for each case.
Preferably, the internal volume of the dip tube is between fifteen and
twenty times the volume of product that is dispensed through the nozzle
arrangement following a single full actuation so that at least twenty full
actuations of product can be dispensed if the container is held at an angle where
the end of the dip tube is not immersed in the product present in the container.
It is especially preferred that the volume is between twenty and thirty times the
volume the volume of product that is dispensed through the nozzle arrangement
following a single full actuation.
The open end of the dip tube is preferably positioned proximate to the
bottom of the interior of the container so that it is immersed in the liquid
product stored therein when the container is upright. However, if the container
is held at an angle where the end of the dip tube is not immersed in the product
present in the container, it will be appreciated that some ah present in the
container will be drawn into the dip tube following each actuation of the pump
or trigger nozzle. This air can be replaced with product by returning the
container to its upright position whereby the open end of the dip tube will be
immersed in the liquid product present within the container and operating the
pump or trigger actuated nozzle arrangement to draw more of the liquid product
into the dip tube and expel any ah present therein.
This mode of operation is not desirable, however, and for this reason, it
is preferable that that the open end of the dip tube through which the contents
of the container are drawn into the dip tube during use is adapted to restrict
access to the dip tube at least when the device is held at an angle where the
open end of the dip tube is not immersed in the product present in the container,
i.e. when it is tilted, inverted, or shaken. Hence, it especially preferred that the
inlet end of the dip tube comprises a constricted opening or valve arrangement
as hereinbefore defined.
The dip tube is preferably resiliently deformable, although it may be
formed of rigid material (but would not work as well). This provides two main
advantages. Firstly, it enables the dip tube to move within the container under
the effect of gravity, which means that the dip tube will, at least to a certain
extent, tend to follow and remain immersed within the product present in the
container as the container is tilted, shaken or inverted. Secondly, by collapsing
the resiliently deformable tube before it is initially placed into the container,
then the product present in the container can be drawn into the dip tube as it
returns to its original resiliently biased /"non-deformed" configuration and
hence, the dip tube is filled ready for the f irst use.
In yet a further aspect of the present invention there is provided a dip
tube adapted to be placed inside a pressurised container having an interior
adapted to store a liquid therein and an outlet valve, said dip tube having an
inlet end through which the contents of the container are drawn into the dip
tube during use and an opposing end which is adapted to be connected to the
outlet valve of the container, wherein the inlet end of the dip tube is adapted to
at least restrict access of fluid into the to the dip tube when the dip tube is
inverted from an upright position.
Conventional dip tubes used in pressurised containers only have a small
internal volume and hence, any product present therein is rapidly exhausted if
the container is held at an angle where the open end of the dip tube is not
immersed in the product present in the container into which it is placed.
Preferably, the dip tubes of the present aspect of the invention has an internal
volume sufficient to enable at least five seconds of continuous actuation of
liquid product to be dispensed, even if the container is held at an angle where
the open end of the dip tube is not immersed in the product present in the
container in which it is placed.
Of course, it will be appreciated that once the product stored in the dip
tube is exhausted when the container is inverted, for example, then gas or ah
present in the container may be ejected instead of product. For this reason, the
internal volume of the dip tube is preferably sufficient to retain sufficient
product therein to enable above average usage of the product while the
container is inverted, tilted or shaken. Hence, the volume required in practice
will vary depending on the application.
Preferably, the internal volume of the dip tube is sufficient to enable
between ten and twenty seconds of continuous actuation if the container is held
at and angle whereby the open end of the dip tube is not immersed in the
product, with an internal volume sufficient to enable between ten and forty
seconds of continuous use being especially preferred.
As previously discussed herein, the provision of the an inlet end of the
dip tube which is adapted to restrict access to the dip tube at least when the
device is held at an angle where the open end of the dip tube is not immersed in
the product present in the container, i.e. when it is tilted, inverted, or shaken,
limits the amount of gas or ah that accesses the dip tube while the open end
thereof is not immersed in the product present in the container into which it is
placed. Hence, it is preferred that the inlet end of the dip tube is provided with
either a constricted opening or, more preferably, a valve arrangement as
hereinbefore defined.
The dip tube may be crushed prior to its initial insertion into the
container so that, once placed in the container, it returns to its original "non-
deformed" configuration and in doing so it fills up with product aheady present
in the container.
The dip tube is also preferably resiliently deformable, as discussed
above, although it may be prepared from rigid material.
How the invention may be put into practice will now be described by
way of example only in reference to the accompanying drawings in which:
Figure 1 is a cross sectional view of a first embodiment of a device of
the present invention, in diagrammatic form;
Figure 2 is a cross sectional view of a second embodiment of a device of
the present invention, in diagrammatic form;
Figure 3 is a cross sectional view of a third embodiment of a device of
the present invention, in diagrammatic form;
Figure 4 is a cross-sectional view of a fourth embodiment of a device of
the present invention, in diagrammatic form;
Figure 5A is an external view of a fifth embodiment of the device of the
present invention, in diagrammatic form;
Figure 5B is a perspective view of the device shown in Figure 5A;
Figure 5C is a perspective view of the outlet end of the device shown in
Figure 5A; and
Figure 5D is a perspective view of an adaptor for fitting the outlet end of
the device shown in Figure 5C to a nozzle arrangement or outlet valve of a
container.
In the following description of the Figures, like reference numerals are
used to denote like or corresponding parts in different Figures.
Figure 1 shows a first embodiment 101 of a device according to the
present invention, which is adapted to be placed inside a container and to
permit a liquid stored in said container to be drawn from the interior of the
container into said device and from said device to the outlet of the container
where it can be dispensed through a nozzle arrangement (not shown).
The device 101 is formed from a flexible and resiliently deformable
plastic material and comprises a body which defines an internal chamber 102,
an inlet 103 having an opening 103a through which the contents of said
container may access the interior of the chamber, and an outlet tube 105, which
connects the device to an outlet valve or pump or trigger actuate nozzle
arrangement so that liquid can be drawn from the chamber 102 to the outlet of
the container (not shown).
The chamber 102 comprises an upper compartment 102b and a lower
compartment 102a. The compartments are linked by a constricted aperture
102c to enable a restricted flow of fluid to occur between them.
The outlet tube 105 extends through an aperture 104 formed on the
upper surface of the device and the aperture 102c into the lower compartment
102a of the chamber where its inlet end 105a is positioned. The opposing end
of the outlet tube 105 is connected to the container outlet (not shown) so that
fluid is drawn out of the device from the bottom portion of the lower
compartment 102a to the outlet during use.
The inlet 103 is comprises a ball valve, which consists of an internal
cavity 103b having a ball bearing 103c present therein. The ball bearing 103c
is capable of movement between a lower position in which the inlet 103 is open
and an upper position in which sit in the opening 103d and forms a seal.
Movement between the lower and upper positions occurs by the effect of
gravity when the device is inverted or tilted from its upright position (as shown
in Figure 1). Hence, when the device is tilted or inverted so that the ball
bearing 103 c moves to the upper position, the inlet becomes sealed and this
prevents the ingress of gas or air from the container in which the device 101 is
placed.
When the container and hence the device 101 placed therein are upright,
fluid is dawn into the device through the inlet and accesses the chamber 102,
where it is then drawn through the outlet tube to the outlet/nozzle arrangement
of die container. If the container is inverted or tilted, the ball bearing 103 c
becomes displaced from the lower position to the upper position and seals the
inlet 102, thereby preventing any gas or ah in the container to which the inlet
has become exposed from accessing the chamber 102. Fluid can continue to be
drawn from the chamber 102 through the outlet tube 105, so product can still be
dispensed from the container. If the dispensing of liquid from the container
continues while the device is inverted of tilted so that the inlet is sealed, the
walls of the chamber will resiliently deform inwards to effectively reduce the
volume of the chamber 102. Once the dispensing of fluid ceases and the
container and the device 101 are returned to the upright position the ball
bearing can be dislodged back to the lower position and liquid can be drawn
into the chamber 102 as the resiliently deformed wall returns to its initial
resiliently biased or non-deformed configuration to replenish that which has
been dispensed.
The reduced pressure within the chamber 102 caused by the resiliently
deformable wall can result in the ball bearing 103c becoming stuck in the upper
position. For this reason, the ball bearing may have to be dislodged from the
upper position by a suitable means. The cavity can be shaped around the
opening 103d so that the ball bearing 103c is only weakly held in the upper
position and thus can readily drop down when it is returned to the upright
position. The ball may also be dislodged by simply shaking the container and
hence, the device placed therein, to cause the ball to drop down to the lower
position. Alternatively, the cavity could be arranged so that there is a small
leak around the ball bearing 103c so that some liquid can seep through the seal
into the chamber to equalise the pressure differential, although this is generally
not preferred because small amounts of gas or ah could seep into the chamber
when the device is inverted or tilted.
The opening 103a is preferably positioned adjacent to the bottom surface
of the container into which it is placed so as to enable virtually all the product
stored in the container to be drawn through the device during use. A further
length of tαbe may be fitted to the opening of the inlet 103a if necessary to
achieve this objective.
The open end of the outlet tube 105a is offset with respect to the inlet
102 so that any gas which accesses the chamber through the inlet (while the
device is upright) rises up past the open end 105 a of the outlet tube and
accesses the upper chamber 102b through the fine aperture 102c. If the
container and the device placed therein are inverted or tilted, then the flow of
any gas or ah present in the upper compartment 102b to the vicinity of the
opening 105a of the outlet tube 105 is impeded by the restricted aperture 102c.
Even if some gas is present and accumulates around the opening o 105a of the
outlet tube 105 when the device is inverted, at least some liquid product will
still access the outlet tube 105 through the hole 106. Thus, some product at
least will be continuously dispensed.
A second embodiment of the present invention is shown in Figure 2.
The device 201 shown in Figure 2 is essentially the same as that shown in
Figure 1 except the inlet 103 is provided with a tube extension 202 which
extends into the upper compartment 102b. Hence, fluid drawn in through the
inlet is introduced into the upper compartment 102b and will access the lower
compartment 102a through the constricted aperture 102c. The advantage of this
construction is that any ah or gas that does manage to access the device through
the inlet will accumulate in the upper compartment 102b when the device is
upright. Furthermore, when the device 201 is inverted or tilted during use, the
flow of gas towards the opening of the outlet tube 105a is inhibited by the
constricted opening 102c. This arrangement would also prevent the device
emptying under effect of gravity, which could theoretically occur with the
device 101 shown in Figure 1.
A simplified device 301 of the present invention is shown in Figure 3.
The device 301 has a chamber 102, which, unlike the embodiments shown in
Figures 1 and 2, does not have upper and lower compartments, an inlet 103 and
an outlet tube 105. As before, the outlet tube 105 extends into the bottom of
the chamber 102. However, in a preferred form of this embodiment, the outlet
tube does not extend into the chamber, but instead is merely received by the
aperture 104, in a similar manner to the arrangement shown in Figure 4 below.
The outlet tube 105 is provided with a hole 106, the function of which is
described above in reference to Figures 1 and 2. The inlet 103 in this
embodiment comprises a constricted opening, which restricts the amount of
product or gas (depending on whether the inlet is immersed in the product or
gas) from the container that can be drawn into the chamber 102. In use, the
contents of the chamber are drawn to the outlet of the container through the
outlet tube 105. This causes the wall of the chamber 102 to resiliently deform
inwards and effectively reduces the volume of the chamber because the
contents of the chamber are not replenished at the same rate through the inlet
103. The chamber then returns to its original configuration after use and the
contents from the container are drawn into the chamber 102 through the inlet
103. It will be appreciated that the constricted opening of the inlet 103 limits
the amount of any gas, which may access the chamber 203 when the container
and the device 301 placed therein is inverted. Likewise, however, the ingress
of liquid while the container and hence, the device 301, are upright is also
restricted. It may therefore take some time for the chamber 102 to refill. The
dimensions of the constricted inlet opening can be selected to control the
amount of time requhed, which may vary from application to application.
The hole 106 provided in the outlet tube of the aforementioned
embodiments described in Figures 1 to 3 is preferable insofar as it improves the
functioning of the device by ensuring that at least a proportion of the product is
dispensed through the outlet at all times, but it shall be appreciated that the
provision of such a hole is not essential and simpler devices could be prepared
without this hole being present.
Furthermore, the outlet tube 105 could be a dip tube to which the device
is attached.
A fourth embodiment of a device of the present invention is shown in
Figure 4. This device 401 is adapted to be fitted to the end of a dip tube 105
via its outlet 104. The dip tube 105 connects a resiliently deformable chamber
102 to an outlet of a container into which the device is placed (not shown). The
chamber 102 is provided with an inlet 103 through which the contents of the
container may access the interior of the chamber 102. The inlet 103 comprises
a ball valve arrangement as previously described above.
In an alternative embodiment, the inlet 103 of the device 401 may be a
constricted opening which serves to restrict the flow of the contents of the
container into the interior of the chamber 102, as described in reference to
Figure 3.
A further alternative embodiment would comprise an outlet tube
(equivalent to tube 204) which is provided with a resiliently deformable
expanded end (bulrush) having a constricted opening thereto.
In yet a further alternative embodiment of the present invention, the
device is in the form of a standard dip tube, equivalent to the dip tube 105,
which is provided with an expanded chamber formed therein or fitted thereto.
This chamber is provided with an inlet opening of equivalent dimensions to the
bore of the dip tube. This device is especially suited for a connection to a pump
or trigger nozzle device. During use, i.e. when the pump or trigger nozzle
device is being operated to actuate the release of the contents stored in the
container, liquid is drawn into the expanded chamber through the inlet and exits
the chamber into the dip tube. If the device is subsequently inverted, tilted or
shaken, then a reservoir of product stored in the expanded chamber will
continue to be dispensed through the outlet following the operation of the pump
or trigger nozzle device. After use, the product dispensed from the expanded
chamber can be replenished by returning the container to an upright position in
which the inlet of the expanded chamber is immersed in the product present in
the container and the operation of the pump or trigger device causes the product
to be drawn into the expanded chamber.
Another embodiment of the present invention comprises a separate
internal compartment formed by placing a resiliently deformable wall in the
bottom of the interior of the container. This compartment has an opening
through which a dip tube extends to draw the contents of the compartment to
the outlet of the container during use. A slow feed of the contents of the
container into the or compartment is provided by a constricted inlet opening,
i.e. a small gap, formed between the edge of the opening and the dip tube,
which connects the compartment to the remainder of the interior of the
container. The hquid product present in the container will flow into the
separate compartment when the container is upright. If the device is tilted or
inverted, the flow of product out of the compartment into the remainder of the
container is restricted. Hence, the product should be continuously dispensed
through the outlet. After use, the product dispensed from the compartment is
replenished by the flow of fluid from the interior of the container into the
compartment through the small gap.
Yet another alternative embodiment is shown in Figures 5A to 5C. This
embodiment of the device 501 comprises an inlet 103, an internal chamber 102
and outlet end 104. The inlet 103 comprises a ball valve (not shown), which
functions in an identical manner to the ball valves described above. In contrast
to the previously described embodiments, however, a separate second chamber
502 is provided around the outside of the chamber 102, as shown in Figure 5C.
The chamber 102 and the second chamber 502 are arranged concentrically. The
chamber 102 is exactly the same in principle as the chambers 102 of the
previously described in reference to Figure 3 and 4. The second chamber 502,
in contiast, is a sealed chamber, which does not have an inlet. Fluid can be
placed in the second chamber 502 and then drawn out of the chamber together
with the product drawn from the chamber 102. The contents drawn out of the
first and second chambers may be mixed prior to entering the outlet valve or
pump or trigger nozzle arrangement to which the device is attached, or,
alternatively, the contents could mix within the outlet valve/nozzle
arrangement, or even expelled separately. In the latter case, however, a
separate pump chamber would be requhed for each chamber that is present in
order to propel its contents to and through the nozzle arrangement. Varying the
dimensions of the outlet of the second chamber 502 can control the rate at
which fluid is drawn out of it during use. A narrow or constricted outlet will
provide a slow rate of flow out of the second chamber, whereas a wider outlet
will enable a higher flow to occur.
Fluid from the second chamber may be drawn out by a venturi effect
caused by fluid flowing from the chamber 102, or may be drawn directly by the
opening of the outlet valve or the actuation of a pump or trigger actuator of a
nozzle arrangement, depending on the circumstances of use.
The walls of both the chamber 102 and the second chamber 502 are
resiliently deformable. However, the second chamber will gradually collapse
over time because fluid is only drawn out of it and is not replenished in the
same way as for the chamber 102.
The outlet end 104 of the device 501 is directly connected to an outlet
valve of a pressurised container, or a pump or trigger nozzle arrangement (in
the case of non-pressurised containers) by means of a suitable adaptor, such as
the adaptor 510 shown in Figure 5D. The adaptor 510 may be a separate
article, which is fitted to the outlet end of the device 501, as shown in Figure
5D, or, alternatively, may be integrally formed with either the device 501 or the
outlet valve or pump/trigger nozzle arrangement to which it is to be attached.
The adaptor 510 is configured to be received within the outlet end 104 of
the device 501. Referring to Figure 5C (which only shows the upper portion of
the device), it can be seen that support segments 505 are provided at the outlet
end of the chamber 502. Theses support segments 505 provide greater rigidity
to the resiliently deformable walls at the outlet end of the device 501, so that
the necessary engagement between the adaptor and the outlet end of the device
can be made. The adaptor 510 comprises a circular protrusion 511, which is
received within the outlet end of chamber 502. An outlet aperture 512 is then
aligned over the outlet end of the chamber 102. An additional outlet aperture
may be provided so that fluid from the second chamber 502 may be drawn into
the outlet valve or pump or trigger nozzle arrangement, or, alternatively, a
passageway connecting this chamber to the outlet /aperture 512 may be
provided.
It shall be appreciated that the embodiments of the invention described
in reference to the Figures are intended to be by way of example only and
should not be construed as limiting the scope of the invention.