Note: Descriptions are shown in the official language in which they were submitted.
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BACKGROIJI\JD OF_ THE INVENTION
This invention concerns an administration set of
the type used for dispensing parenteral liquid to a
patient, and, more particularly, to an administration
; set including a burette having a pivotable air valve~
dministration sets including burettes with drip
chambers are widely used ~or administering parenteral
liquids to a patient. The burettes typically include a
burette chamber with a primary liquid inlet to the
chamber and also an injection site communicating with
the chamber for injecting medicament into the chamber
so that, fox example, the medicament may be diluted
; with the primary liquid.
When the buxette is being filled with liquid or
medicament is being injected into the burette for
dilution with the liquid, communication of the burette
chamber with the air outside the chamber is necessary.
To this end, in one prior art administration set con~
struction, an air tube communicates with the burette
chamber, with the air tube having a filter at one end
and a clamp between the filter and the burette chamber.
- When it is desired for the burette chamber to be open
to air, the clamp is opened.
In another prior art construction, as disclosed
in McPhee U.S. Patent No. 3,776,229, a rotatable air
valve communicates with the burette chamber for providing
the necessary air vent. However, -the rotary air valve
disclosed in this patent has certain disadvantages. For
example, because of the grooved construction of the
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system, the rotatable portion of the air valve can be
easily pulled off by an operator. Additionally, it has
been found that the air valve disclosecl in this patent
generally requires silicone lubricant in order to provide
adequate sealing properties when the valve is closed.
This is disadvantageous hecause the silicone lubricant
may become introduced into the burette. Further, the
filter carried within the air valve may become clogged,
particularly when the unit is shaken by the operator,
and there is no way to unclog the filter once i-t becomes
clogged.
Accordingly, it is an object of the present
invention to provide an administration set having a
burette which obviates the requirement for an air tube
extending from the burette chamber with a clamp between
the air filter and the burette chamber.
Another object of the present invention is to
provide an administration set with a burette having a
pivotable air valve of the type that cannot be easily
removed by an operator.
A further object of the present invention is to
provide an administration set having a burette which uses
an air valve that does not require silicone lubrication.
A still further object of the present invention
is to provide an administration set having an air valve
which is structurally arranged to allow an operator to
at least partially unclog the filter carried by the air
valve, if the filter should become clogged.
Other objects and advantages of the present
invention will become apparent as the description proceeds.
SUMMARY OF TIIE INVENTION
The invention relates broadly to a med:ical
device having a chamber, an air valve comprising a
stationary port extending from a wall of the chamher
and defining a bore therethrough, the port including
a fitting shaped to define an open internal portion,
an outer portion of the fitting shaped to define a
passageway~ the fitting closing the port except for
the passag~way, with the passageway being substantially
smaller than the open internal portion, a pivotable
closure overlying the passageway in the outer portion
of the fitting and being pivotally connected therewith,
the pivotable closure shaped to define an opening for
~- communication with the passageway when the closure is
pivoted to a predetermined open position, and means
for segregaiing the closure opening from the passageway
when said closure is in its closed position, the
segregating means comprising a resilient member movable
with the pivoting movement of the closure to close and
seal the passageway when the closure is not in the
predetermined open position, the fitting being proportionea
to compress the resilient member while it is closing
and sealing the passageway.
In accordance with a particular aspect of the
present invention, an administration set is provided
of the type including a burette having a burette chamber
and a main liquid inlet, an injection site and an air
valve communicating with the chamber, and a drip chamber
connected downstream of the burette chamber. The
improvement comprises the air valve comprising a
stationary port extending from a top portion of the
burette chamber and defining a bore therethrough. The
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port includes a fitting defining an open internal
portion with the fitting closing the port except ~or
a passageway defined by a top portion of the fitting.
The passageway is substantially smaller than the open
internal portion.
;~ A pivotable closure overlies the port and is
pivotally connected therewith. The pivotable closure
defines an opening for communication with the passageway
when the closure is pivoted to a predetermined open
position.
; Means are provided for segregating the closure
opening and the passageway when the closure is not in
its predetermined open position. A filter member is
located transverse the bore and directly underlies
the passageway.
In the illustrative embodiment, the stationary port
comprises an open annular member and a separate fitting
fastened to the open annular member~ The pivotal
connection is between the separate fitting and the
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pivotable closure and comprises a circular flange and
cooperating groove arranyement with khe fitting carrylng a
fl-rge and the clo~ure defining a cooperating groove. The
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pivotable closure includes an arm extending therefrom to
provide manual grasping and the closure and stationary
port have a secure pivotal connection preventing an
operator from removing the closure from the port.
In the illustrative embodiment, the segregating
means comprise a resilient member movable with a pivoting
member of -the closure, to close and seal the passageway
when the closure is not in the predetermined open position.
The resilient member comprises a ball carried by the
closure and spaced from the opening defined by the closure,
and the fitting defines an inclined groove for receiving
the ball when the closure is pivoted to its predetermined
open position. The inclined groove is dimensioned so as
to enable the ball to not be under compression when the
closure is in its predetermined open position, and so as
to enable the ball to move up the incline when the
closure is pivoted to a closed position, to place the
ball under compression, sealing the passageway when the
closure is in a closed position.
A more detailed explanation of the invention is
provided in the following description and claims, and is
illustrated in the accompanying drawings.
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BRIEF DESCRIPTION_ OF THE DRAWINGS
FIGURE 1 is a view of an administration set
constructed in accordance with the principles of the
present inventiorl;
FIGURE 2 is a front view, partially broken for
clarity, of a burette and associated drip chamber used
in connection with the administration set of FIGURE 1;
. FIGUR~ 3 is a top view of the burette of FIGURE 2,
with possible movement of the pivotable valve illustrated
in phantom lines;
FIGUP~ 4 is a cross-sectional view thereof, taken
;~ along the plane of the llne 4-4 o~ FIGVRE 3;
FIGURE 5 is a greatly enlarged, fragmentary,
cross-sectional view of the pivotabl.e alr vent in its
predetermined open position; and
FIGU~E 6 is a greatly enlarged, fragmentary view
thereof, ~ith the pivotable valve shown in a closed
positlon.
DETAILED DESCRIPTION OF THE
ILLUSTRAT VE 5MBODIMENT_
Referring to FIGURE 1, an administration set
constructed in accordance with the principles of the
present invention is shown therein The administration
set includes a conventional spike 10 for coupling to a
source of parenteral liquid, tubing 12 connected to main
liquid inlet 14 (FIGURE 4~ of a burette 16~ the burette
~-` having a drip chamber 18 extending from the bottom thereof
and in series with the flow line, a roller clamp 20,
tubing 22 connected from drip chamber 18 to an injection
site 24, roller clamp 26 on tubing 22, and tubing 28
connected from the outlet of injection site 24 to a
` conventional needle adapter 30.
Referring now to FIGURES 1-4, the burette 16
: includes a burette chamber 32 having a platform 34 at its
outlet end supporting a filter 36, and having an inlet
assembly 38 at its inlet end. Inlet assembly 3a includes
: main liquid inlet 14 of conven-tional construction, an
injection site 40 of conventional construction, and a
novel pivotable air valve 42.
Air valve 42 is shown in detail in FIGURES 4-6.
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As illustrated therein, the air valve includes an upstand-
ing annular stationary port 44, which in the illustrative
embodiment is foxmed integrally wi~h the base 46 of inlet
assembly 38. Port 44 carries a central member 48 which
defines an axial bore 50. Port 44 also deEines a shoulder
52 which suppoxts air filter 54. Air filter 54 is
preferably circular and dimensioned so as to fit securely
in a resting position on shoulder 52.
Within the internal wall 55 of port 54, there is
pressure-fitted a fitting 56 which defines an open
internal portion 58 and closes port 44 except for a
passageway 60. Passageway 60 is defined by the top
portion 62 of fitting 56 and the passageway is much
smaller than the open internal portion 58.
The external sidewall 64 of fitting 56 carries
an annular flange 66 which cooperates with an internal
groove 68 of a pivotable closure '70, to form a pivota,l
connection between pivotable closure 70 and stationary
fitting 56.
Pivotable closure 70 comprises a top wall 72
: defining an opening 74 for communication with passageway
60 when the closure is pivoted to a predetermined open
position, and an annular sidewall 76 which extends
downwardly and externally of port 44. Sidewall 76 is
dimensioned ~o that when the pivotable closure 70 is
snapped onto fitting 56, there is a relatively close fit
between the internal surfaces of sidewall 76 and the
external surfaces or fitting 56 and port 44. However,
the coupling is such that the pivotable closure 70 can
rotate with respect to stationary port 44 and fitting 56.
Pivotable closure 70 also has a raised portion 78
which defines an arc 80 for receiving a resilient ball 82.
Resilient ball 82 is preferably a silicone rubber sphere
which is ~ltili~ed to seal passageway 60 when the closure
70 is not in its predetermined open pos.ition. Closure 70
also carries a radi.ally extending, manually-graspable
handle 84 for enabling the operator to pivot the closure
easily.
As shown in FIGURES S and 6~ fitting 56 defines
;~ a groove 86 having an incline 88, which incline leads to
the top of passageway 60. As illustrated in FIGURE 5,
when the closure 70 is in its predetermined open position,
ball 82 will lie within groove 86 and opening 74 will be
aligned with passayeway 60. Arc 80 and groove 86 are
- dimensioned so that ~all 82 will not be in a compressed
~ state in its position illustrated in FIGUR~ 5. When arm
~ 84 is turned so that closure 70 is not in its predeter-
mined open position, ball 82 will be moved to seal
passageway 60 as illustrated in FIGURE 6. In this
position, the hall 80 is under compression to provide an
effective seal.
By utilizing the aforementioned construction, a
highly effective pivotable air valve is provided. The
pivotable closure is securely pivotally connected to the
.^ stationary portion, the use of silicone lubricant to
provide adequake sealing properties is unnecessary and
if fil-ter 54 is clogged, a needle can be inserted through
opening 74 and passageway 60 to at least partially unclog
the filter, as the filter directly underlies passageway
60.
As shown in FIGURE 3, a stop member 90 is con-
nected to the assembly for limiting the pivotal movement
of closure 70 and a stop member 9~ is also provided for
limiting the pivotal movement of the closure 70 in the
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opposite direction.
Although an illustrative embodiment of the inven-
tion has been shown and described, it is -to be understood
that various modifications and substitutions may be made
: by those skilled in the art without departing from the
novel spirit and scope of the present invention.
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