Note: Descriptions are shown in the official language in which they were submitted.
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VALVED NOZZLE FOR RE-USABL:E: RESERVOIR
OF A FLOWABLE PRODUCT
This invention relates to a nozzle having a control
valve for use with a re-usable reservoir of a ~10wable product.
A flowable pharmaceutical, for example a pharmaceutical
jelly may be stored in a capped collapsible container, typically
a capped aluminium tube. When it is desired to dispense some of
the pharmaceutical, the cap is removed and typically replaced by
a nozzle which provides anl-ni ~.cded passageway between the tube
and the dispensing end of the nozzle. The nozzle is then
directed to the position where the pharmaceutical is to be
dispensed, such as in a body orifice, and the container squeezed
until the desired amount of pharmaceutical is dispensed. Aftsr
use, the noz~le is removed, cleaned and then sterilised and the
container recapped whereupon the nozzle and containe~ are ready
for re-use. A problem with this approach is that the flowable
pharmaceutical may degrade the metals used in the collapsible
tube thereby limiting the storage life of the pharmaceutical
containing tube. In order to overcome this drawback, it is known
to use a resilient plastic tube containing the pharmaceutical
which may receive a nozzle incorporating a one-way valve. The
known valved nozzle is described in greater detail hereinafter.
Briefly, this nozzle incorporates a valve float, a float stop and
a valve seat. The float stop occasionally unseats thereby
impeding normal operation. Also, because the rloat and float
stop are typically made in moulds, flashing may occur which can
impede proper operation; flashing has been found to be a problem
w.ith the Ploat stop. The nozzle could be disassembled for
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cleaning, however, the small size of the nozzle components made
disassembly and re-ass~mbly difficult. This known nozzle is
described in greater detail hereinafter.
This invention seeks to overcon~e drawbacks of known
nozzles.
According to this invention, there is provided a nozzle
for attachment to the discharge port of a dispensing container
containing a flowable pharmaceutical, said container of the type
providing a positive pressure to dispense pharmaceutical through
said nozzle and a negative pressure on termination of dispensing,
said nozzle comprising: an entry end and a dispensing end and a
cavity running between said entry end and said dispensing end;
means for attaohing the entry end of said nozzle to the discharge
port of a dispensing container; a valve seat within said nozzle
cavity; a float stop within said nozzle cavity positioned between
said valve seat and said dispensing end of said nozzle, said
~loat stop comprising an annular abutment in said interior
cavity; a float within said nozzle cavity positioned between said
valve seat and said float stopl said float having ~i) a v~lve
seating end directed toward said valve seat and configured so as
to be seatable therein, (ii) a float stop abutting end directed
toward said float stop and configuxed so as to be capable of
abutting therewith, ~iii) fluted sides extending to said float
stop abutting end, said float moveable between a first position
whereat said valve seating end of said float seats on said valve
seat and closes said nozzle and a second position whereat said
float stop abutting end abuts said float, said flutes provide
fluid c~- nication through said nozzle and said float is at a
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predetermined standoff from said valve seat, said standoff chosen
so that the suck back gen rated on termination of dispensing
draws flowable pharmaceutical at said dispensing end of said
nozzLe into said nozzle to reduce dripping and reseats said float
in said valve seat without allowing contaminated pharmaceutical
to enter said container and without significant damage to any
tissue with which said nozzle may be associated,
whereby when said nozzle is attached to the discharge port of a
dispensing container and said container supplies a positive
pressure for dispensing pharmaceutical, the positive pxessure
generated in said nozzle causes said float to lift ofF said valve
seat and abut said float stop so that flowable pharmaceutical in
said container may be discharged through the discharge end of
said nozzle and whereby, on termination of dispensing, the
negative pressure in said no~zle sucks flowable pharmaceutical
at said dispensing end o~ said co~tainer into said nozzle and
said ~loat into seating relation with said valve seat to close
said nozzle, the predetermined standoff of said float from said
valve seat ensuring no contaminated pharmaceutical re-enters ~aid
container and i ni ; zing damage to any tissue with which said
nozzle may be associated~
According to another aspect of the invention, there is
provided a nozzle for attachment to the discharge port of a
dispensing container containing a flowable product, said
container of the type for providing a positive pressure to
dispense product through said nozzle and a negative pressure on
termination of dispensing, said nozzle comprising: an entry end
and a dispensing end and a cavity running between said entry end
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and said dispensing end, said cavity comprising an annular
receptor opening to said antry end; means for attaching the entry
end of said nozzle to the discharge port of a dispen~ing
container; a valve seat within said nozzle cavity comprising a
resilient O-ring received by said annular receptor and removable
from said cavity through said entry end thereof, a float stop
within sa d nozzle cavity positioned between said valve seat and
said dispensing end of said nozzle, said float stop comprising
an annular abutment in said interior cavity; a float within said
nozzle cavity positioned between said valve seat and said float
stop, said float having ti) a valve seating end directed toward
said valve seat and configured so as to be seatable therein, (ii)
a float stop abutting end directed toward said float stop and
configured so as to be capable of abutting therewith, ~iii)
fluted sides extending to said float stop abutting end, said
float moveable between a first position whereat said float seats
on said valve seat and closes said nozzle and a second position
whereat said float abuts said float stop such that said nozzle
is opened and said float is at a predetermined standoff from said
valve seat, said standoff chosen so that the suck back generated
on termination of dispensing reseats said float in said valve
seat, said float being removable from said nozzle cavity once
said O-ring has been removed~ whereby when said nozzle is
attached to the discharge port of a dispensing container and said
container supplies a positive pressure for dispensing product,
the positive pressure generated in said nozzle causes said float
to lift off said valve seat and abut said float stop so that
flowable product in said container may be discharged through the
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discharge end of said nozzle and whereby, on termination of
dispensing, the negative pressure in said nozzle sucks said float
into seating relation with said valve seat to close said nozzle
and whereby when said O-ring and said float are removed from said
nozzle, cleaning is thereby facilitated so that the nozzle, once
cleaned, may be reassembled and sterilised for reuse.
In the figures which disclose example embodiments of
the invention,
figure 1 is a side sectional view of a prior art nozzle attached
to a container,
~igure 2 is a series of views of a portion of figure 1,
figure 3 is a side sectional view of a no~zle made in accordance
with this invention attached to a container,
figure 4 is a side sectional view of the nozzle and container of
figure 3 showing the nozzle in an open position, and
figure 5 is a side and end view of a portion of figures 3 and 4.
Figures 1 and 2 illustrate the above mentioned known
valved nozzle. With reference to figure 1, nozzle 110 comprises
housing 111 and an interior cavity 112 running between an entry
end 114 and a dispensing end 116. The interior cavity has a
threaded portion 118 running from the entry end; this threaded
portion serves as a means for attachment to the threaded
discharge port 120 of a resilient dispensing container 122
~illustrated in phantom) containing a flowable pharmaceutical148
such as a pharmaceutical jelly. The interior cavity also
comprises an enlarged medial portion 124, a reduced diameter
portion 126 running from the dispensing end 116 and a tapered
portion 125 running between the enlarged medial portion 124 and
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the reduced diameter portion 126. An annular receptor 128
between the threaded portion 118 and the enlarged medial portion
124 o~ the in~erior cavity 112 receives a resilient O-ring 130.
The 3-ring, when received within the receptor, acts as a valve
seat 140 as will become apparent hereinafter. It should be noted
that the receptor 128 opens to the entry end 114 of the nozzle
which permits removal of the O-ring 130. It may also be noted
that the threaded disGharge port of the dispensing container i5
normally screwed into the threaded portion of the nozzle 110
until the end 115 of the discharge port contacts the O-ring 130.
A float stop 142 is press fit into the tapered section
125 of the interior cavity of the nozzle. The float stop is
illustrated in greater detail in figure 2. With raference to
figure 2 it is seen that the float stop is cruciate shaped in
cross section and is tapered. The float stop includes four
divergent fingers 150 about its circumference which form a float
receiving area 152. Returning to figure 1, it will be apparent
that, due to the cruciate shape of the float stop, four ch~nn~ls
are formed between the noz2le housing 111 and the float stop when
the float stop is press fit into the tapered section of the
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interior cavity of the nozzle.
A float 134, comprising a spherical ball, is received
within the interior cavity between the valve seat 140 and the
float stop 142. The float may be moved between a position
whereat it seats on the valve seat, as shown in phantom in figure
1 and a position whereat it is received between fingers 150 of
the float stop and abuts the float stop, as is illustrated in
figure 1. When the float is seated in the valve seat 140, the
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interior cavity 112 of the nozzle is closed off, thus closing the
nozzle. When the float abuts the float stop, there is fluid
communication between the entry end and dispensing end of the
nozzle since fluid may pass around the float and along the
channels formed between the float stop and the nozzle housing
into the reduced diameter portion 126 of the nozzle. When the
float abuts the float stop 142, the float is at a fixed stand-
off 144 from the valve seat 140, thus, the stand-off is a measure
o~ the distance the float would need to move to seat on the valve
seat. This stand-off is typically chosen to be approximately
one-eighth of an inch which ensures no significant damage is done
to any tissue with which the nozzle is in intimate contact, as
will become more apparent hereinafter. Furthermore, the length
o~ the portion 126 of the cavity 112, is about three times the
standoff, ~or reasons which will become apparent hereinafter.
In operation of the prior art nozzle, a resilient
container 122 may be capped. When it is desired to dispense the
flowable pharmaceutical 148 contained therein, the cap may be
removed and the threaded dispensing port screwed into the
threaded portion 118 of nozzle 110 until the end oi the
dispensing port snugs up against the O-ring 130 of the nozzle.
The nozzle may then be directed to the area requiring an
application of the pharmaceutical. This may be a body orifice
or the portion of a probe intended to be inserted into a body
orifice. Once the nozzle has been directed appropriately, the
resilient container may be squeezed. This creates a positive
pressure (i.e., a pressure greater than atmospheric pressure) in
the nozzle which pushes the float 134 into abutment with the
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float stop 142. With the float abutting the ~loat stop,
pharmaceutical is free to be expelled from the container and
through the interior cavity 112 of the nozzle 110 to the
dispensing end thereof. Dispensing is terminated by releasing
the squeezing pressure from the container whereupon, due to its
resilience, the container attempts to return to its original
shape. This results in a negative pressure (i.e., a pressure
less than atmospheric~ in the nozzle 110 which sucks the float
134 toward the container 12~ and into seating relationship with
the valve seat 140. Once the float seats in the valve seat, the
nozzle is closed off. Furthermore, the container will not have
returned to its original shape when the nozzle is closed off
(since the volume increase of the container during suck back will
always be less than the decrease in volume in the container when
pharmaceutical has been pushed past the float and expelled from
the nozzle), consequently the container will apply a static
negative pressure to the float which will retain it in seating
relation with the valve seat.
Where the nozzle is intimately associated with delicate
tissue inside a body ori~ice, suck back in the nozzle risks
damage to the tissue. This requires that the suck back be
limited and this is accomplished by limiting the stand off. On
the other hand, sucking back into the nozzle pharmacautical at
the dispensing end of the nozzle on termination of dispensing
draws any drip of pharmaceutical formed at the dispensing end
back into the nozzle if the float stand off is sufficiently
large. Hence, a sufficiently large suck back assists in the
prevention of the dripping of contaminated pharmaceutical from
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the nozzle. To balance these competing factors, the stand off
is about one-eighth of an inch~ With the length of portion 126
of the cavity chosen as about three times t:he standoff 144, none
of the contaminated pharmaceutical which is sucked back into the
nozzle can re~enter the container. This allows the container to
be re-used.
After use of the nozzle-container assembly, the nozzle
may be removed from the container and the container re-capped.
The nozzle may then be readied for cleaning and sterilisation by
pulling the O-ring 130 off the ~nnul ~r retainer 128 ancl out of
the nozzle housing through the threaded section 118 of the
interior cavity of the nozzle housing and subsequently removing
the float and pulling the float stop 142 from end 114 of the
nozzle housing. Thereafter the nozzle housing and the separated
float, O-ring and~float stop may be cleaned and the nozzle re-
assembled by press fitting the float stop into the tapered
section of the nozzle's interior cavity and reinserting the float
then reseating the O-ring. The re-assembled nozzle may then be
sterilised for reuse.
Since the end user must disassemble and re-assemble the
nozzle, the interference fit of the ~loat stop in the nozzle
cannot be too great. A consequence of this limitation is that
the float stop can work itself out of the tapered portion 125 of
the interior cavity of the nozzle. If this occurs, the a~ml1m
stand off of the float 134 from the valve seat will be reduced
thereby making dispensing of viscous jelly from the nozzle
difficult. Furthermore, float 134 could be precluded from
lifting off the o-ring 130 altogether, rendering the nozzle
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inoperative~
The nozzle of figure 1 has three parts which must be
removed from its interior cavity to permit cleaning and one of
these parts is removed with some difficulty due to the fact that
it is press fit in place. These factors complicate cleaning and
sterilisation of the nozzLe.
; Additionally, the valve float and float stop are
typically formed with moulding techniques. The cruciate shape
o~ the float stQp makes it susceptible to ft~shing at both ends,
this flashing may partially obstruct the interior cavity of the
nozzle making dispensing more difficult.
Turning to ~igure 3 which illustrates an embodiment of
the subject invention, a nozzle 10 has a housing 11 and an
interior cavity 12 running between an entry end 14 and a
dispensing end 16. The interior cavity has a threaded portion
18 running from the entry end; this threaded portion sarves as
a means for attachment to the threaded discharge port 20 of a
dispensing container 22, sho~n in phantom in figure 1. The
interior cavity also comprises an enlarged medial portion 24 and
a reduced diameter portion 26 running between the enlarged medial
portion 24 and the dispensing end 16 of the nozzle. An annular
receptor 28 between the threaded portion 18 and the enlarged
medial portion 24 of the interior cavity 12 receives a resilient
O-ring 30. The O-ring, when received within the receptor, acts
as a valve seat 40. The receptor 28 opens to the threaded
portion side of the nozzle which permits removal of the O-ring
30. The threaded discharge port of the dispensing container is
normally screwed into the threaded portion of the nozzle 10 until
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the end 15 of the discharge port contacts the 0-ring 30.
The juncture between the enlarged medial portion 24 of
the interior cavity 12 and the reduced diameter portion 26
comprises an annular abutment 32 which acts as a float stop 42,
as will become apparent hereinafter. It is noted that the float
stop 42 is an integral part of the nozzle housing 11.
A float 34 is received within the interior cavity
between the valve seat 40 and the float stop 42. With reference
to figure 5 as well as ~igure 3, the float comprises a
hemispherical end 36, with the hemispherical face directed toward
the valve seat and a plurality of legs 38 arranged about a core
37 and depending from the hemispherical end and directed toward
the float stop. Flutes 3g are formed between adjacent legs. The
legs 38 project beyond the end 35 of the core 37.
~' The float may be moved between a position whereat the
hemispherical end 36 seats on the valve seat, as shown in figure
3 and a position whereat the ends of the legs of the float abut
the float stop 42, as illustrated in figure 4. When the float
is seated in the valve seat 40, the interior cavity 12 of the
nozzle is closed o~f, thus closlng the nozzle. When the float
abuts the float stop, there is fluid communication between the
entry end and dispensing end of the nozzle since ~1uid may pass
around the hemispherical end of the float and along the flutes
39 between the legs 38 of the float into the reduced diameter
portion 26 of the no~zle. The medial portion 24 of the interior
cavity 12 tapers towards the float stop which ensures the float
is centred when it moves toward the float stop so that the legs
38 of the float contact the annular ~loat stop.
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When the float abuts the float stop 42, the float is
at a fixed stand-of~ 44 from the valve seat 40, thus, as before,
the stand-off is a measure of the distance the float would need
to move to seat on the valve seat. This stand-off is chosen to
'~ be approximately one-eighth of an inch which ensures no
significant damage is done to any tissue with which the nozzle
is in intimate contact. The length of the portion 26 of cavity
12, which is the distance 46 between the float stop and the
dispensing end 16 of the nozzle should be at least about three
times the standoff 44 to ensure contaminated pharmaceutical does
not enter the container 22, as will become more apparent
hereinafter.
The dispensing container 22 contains a flowable
pharmaceutical 48, such as a pharmaceutical jelly. The container
is made of a resilient material, such as a resilient plastic.
; The operation of the nozzle is similar to the operation
of the nozzle 110 and is as follows. The threaded dispensing
port of container 22 may be screwed into the threaded portion 18
of nozzle 10 until the end of the dispensing port snugs up
against the O-ring 30 of the nozzle. The nozzle may then be
.
directed to the area requiring an application of the
; pharmaceutical. This may be a body orifice or the portion of a
probe intended to be inserted into a body orifice. Once the
nozzle has been directed appropriately, the resilient container
may be squeezed. This creates a positive pressure in the nozzle
which pushes the float 34 into abutment with the float stop 42.
With the float abutting the float stop, pharmaceutical is free
~ to be expelled from the container and through the interior cavity
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12 of the nazzle 10 ko the dispensing end thereof. Dispensing
is terminated by releasing the squeezing pressure from the
container 22 whereupon, due to its resilience, the container
attempts to return to its original shape. ~his results in a
negative pressure in the nozzle 10 which sucks the float 34
toward the container 22 and into seating relationship with the
valve seat 40. Once the float seats in the valve seat, the
nozzle is closed off. Furthermore, the container will not have
returned to its original shape when the nozzle is closed off
(since the volume increase of the container 22 during suck back
will always be less than the decrease in volume in the container
when pharmaceutical has been pushed past the float and expelled
from the nozzle), consequently the container will apply a static
negative pressure to the float which will retain it in seating
relation with the valve seat~
The negative pressure in the nozzle prior to the
seating of the float on the valve seat draws pharmaceutical back
into the nozzle through the dispensing end 16 thereof. Where the
nozzle has been inserted in a body orifice, this returned
pharmaceutical is contaminated. Xowever, it is intended that the
container 22 be re-used ~if a significant quantity of
pharmaceNtical remains therein), consequently, this contaminated
pharmaceutical must not re-enter the container. With the
distance 46 between the dispensing end of the nozzle and the
float stop chosen as at least three times the stand off ~, no
contaminated pharmaceutical can reach the container even where
the float is significantly denser than the flowable
pharmaceutical.
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Where the nozzle is intimately associated with delicate
tissue inside a body ori~ice, suck back in the nozzle risks
damage to the tissue. It has been determined that limiting the
stand off to about one eighth of an inch or less will m~nl~ize
the risk of tissue damage (independent of the cross-sectional
area of the nozzle opening at the dispensing end of the nozzle).
Since pharmaceutical at the dispensing end of the
nozzle is sucked back into the nozzle on termination of
dispensing, any drip of pharmaceutical formed at the dispensing
end will be drawn back into the nozzle if the float stand off is
sufficielltly large. It has been found that a stand off of about
one eighth of an inch is sufficient to draw a drip of
pharmaceutical into the nozzle for pharmaceuticals of typical
viscosities. Hence, the suck back will assist in the prevention
of the dripping of contaminated pharmaceutical from the nozzle.
In the result, a stand off of about one eighth of an
inch will be sufficient to draw a drip at the end of the nozzle
into the nozzle while m; nir;zing the risk of tissue damage.
~; After use o~ the nozzle-container assembly, the nozzle
may be removed from the container and the container re-capped.
. ~
The nozzle may then be readied for cleaning and sterilisation by
pulling the O-ring 30 off the annular retainer 28 and out of the
nozzle hou~ing through the threaded section 18 of the interior
cavity of the nozzle housing and subsequently removing the float
from end 14 of the nozzle housing. Thereafter, the nozzle
housing and the separated float and O-ring may be cleaned and
the nozzle re-assembled and sterilised. The sterilised nozzle
and the re-capped container are then ready for re-use.
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It will be noted that nozzle 10 has only two removable
parts in its interior cavity rather than the three parts of the
known nozzLe 110. Furthermoret since neither part is pres~ fit
into the nozzle their removal i5 facilitated. Thus, the nozzle
10 may be more readily disassembled ~or cleaning and re-assembled
to permit sterilisation than the previously known nozzle 110.
The diameter of the enlarged medial portion 24 of the
interior cavity of the nozzle and of the float 34 are chosen so
that the float is constrained to predomin~ntly axial movement in
the cavity (that is, any pivoting of the float within the cavity
is limited). This ensures the legs 38 of the float will abut the
~loat stop 42 (which is an integral part of the nozzle housing)
when the float is pushed against the float stop. This nozzle
arrangement avoids the need Eor an integral nozzle housing of
complicated construction while also avoiding the need for a press
fitted float stop. Avoiding the need for a float stop that must
be press fit into the nozzle cavity ensures that the selected
stand-of~ for the nozzle is maintained at all times.
The hemispherical end 36 of the float 34 is not sub~ect
to flashing; thus, fl~shlng is possible only at the legged end
of the float. Accordingly, flashing on the moulded part of the
nozzle 10 is less than the flashing on the moulded parts of the
nozzle 110. Hence the chances of restricted flow through the
nozzle 10 due to flashing are reduced.
Resilient container 22 may be replaced with any other
container of the type providing a positive pressure to dispense
its contents and a suck back pressure on termination of
dispensing. Thus, for example, the container could comprise a
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syringe.
The no~zle of this invention may be used with ~lowable
products other than pharmaceuticals. For example, the nozzle may
be used in dispensing an air drying glue. In such an
application, the maximum stand off is not critical, however the
suck back on te~in~tion o~ dispensing closes the nozzle valve
which ensures glue r~ ~ining in the container is not exposed to
air and hence does not dry whilP in the container~ Furthermore~
the ability to disassemble the nozzle allows it to be cleaned
for reuse.
Other modifications will be apparent to those skilled
in the art and, accordingly, the invention is defined in the
claim~.
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