U.S. patent application number 12/157866 was filed with the patent office on 2009-12-17 for rack and pinon drive for by-pass cartridge.
Invention is credited to Daniel MacDonald, Roger McCarthy, David L. Reynolds.
Application Number | 20090308895 12/157866 |
Document ID | / |
Family ID | 41413831 |
Filed Date | 2009-12-17 |
United States Patent
Application |
20090308895 |
Kind Code |
A1 |
Reynolds; David L. ; et
al. |
December 17, 2009 |
Rack and pinon drive for by-pass cartridge
Abstract
A device for mixing a substance comprised of two constituents
contained in a cartridge and having a cartridge holder thereabout,
the device comprising a plunger rod for pushing the closure member
to permit the transfer of a diluent in a first chamber through a
by-pass channel to mix with a constituent in a first chamber, the
plunger rod being driven by means of a rack and a pinion gear
arrangement to prevent overly rapid movement of the plunger
rod.
Inventors: |
Reynolds; David L.;
(Bromont, CA) ; MacDonald; Daniel; (Bromont,
CA) ; McCarthy; Roger; (Brigham, CA) |
Correspondence
Address: |
Eric Fincham
316 Knowlton Road
Lac Brome
QC
J0E 1V0
CA
|
Family ID: |
41413831 |
Appl. No.: |
12/157866 |
Filed: |
June 13, 2008 |
Current U.S.
Class: |
222/327 ;
222/386; 222/390 |
Current CPC
Class: |
B01F 15/0201 20130101;
A61M 2005/3152 20130101; A61M 5/2448 20130101; B01F 13/002
20130101; B01F 15/0087 20130101; B01F 13/0023 20130101; B01F
15/0237 20130101 |
Class at
Publication: |
222/327 ;
222/386; 222/390 |
International
Class: |
B65D 88/54 20060101
B65D088/54; G01F 11/00 20060101 G01F011/00 |
Claims
1. A device for mixing a substance comprised of two constituents,
the device comprising: a cartridge; a cartridge holder; said
cartridge having a fluid communication end and an actuation end,
said fluid communication end being receivable in said cartridge
holder, the tubular container having a first closure member
disposed at the fluid communication end, a second closure member
disposed at the actuation end, a piston within the container
intermediate the first and second closure members, and a by-pass
channel for enabling fluid to by-pass the piston when the piston is
in the by-pass position; a plunger rod engageable with the second
closure member for moving the second closure member within the
cartridge, said plunger rod having a rack gear formed thereon; a
housing, a pinon gear mounted within said housing, said pinon gear
being engageable with said rack gear, and a handle connected to
said pinion gear.
2. The device of claim 1 further including a cap at a distal end of
said cartridge, said cap having a piercing member with a fluid
passageway therein, and a hydrophobic membrane associated with said
passageway to permit the egress of gas therethrough while
preventing the passage of liquid.
3. The device of claim 1 wherein said handle comprises a thumb
wheel, the arrangement being such that a turning of said thumb
wheel drives said pinon gear which in turn drives said rack gear to
advance said plunger rod.
4. The device of claim 3 wherein said housing is screw threadedly
engaged with said cartridge holder.
5. The device of claim 2 wherein a first chamber is defined between
said first closure member and said piston and a second chamber is
defined between said second closure member and said piston, said
first chamber containing a dry constituent and said second chamber
containing a diluent therefore.
6. The device of claim 1 wherein said hydrophobic membrane is
secured to a top of said cap, said hydrophobic membrane extending
over said passageway.
7. The device of claim 2 wherein said cap is screw threadedly
engaged with said cartridge holder.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a by-pass cartridge and in
particular to a device and method for storing, mixing and
delivering pharmaceuticals.
BACKGROUND OF THE INVENTION
[0002] In pharmaceutical delivery systems, it is sometimes
necessary to mix a drug in powder form with a diluent in order to
be able to deliver the drug to a subject. This can be done manually
by injecting the diluent into a vial containing the powdered drug,
mixing the drug into the diluent and aspirating the drug in fluid
form into a syringe for subsequent injection into the subject. Such
manual procedures are generally considered to be cumbersome and
inconvenient and often lead to wastage of some of the drug as it
may remain in the vial.
[0003] Also known in the art are dual chambered syringes which use
a by-pass channel to provide fluid communication between the two
chambers. The two chambers are commonly defined within a syringe
barrel by two separate pistons and an end stopper spaced apart
within the syringe barrel. In such an arrangement, the two chambers
are placed in fluid communication by the by-pass channel by
actuation of the outer most piston within the syringe barrel. This
causes both pistons within the syringe barrel to advance to a point
where the inner most piston becomes aligned with the by-pass
channel. At that point, further actuation of the outer most piston
causes fluid contained in the chamber between the two pistons to
flow into the outwardly extending by-pass channel and around the
inner most piston which remains stationary.
[0004] With the two chamber syringe barrel and external by-pass
arrangement described above, a danger exists in the possibility
that the inner most piston is pushed too far along such that it
goes past the by-pass channel before full transfer of the diluent
occurs. This may be caused by an overly vigorous application of the
plunger to the outer most piston. Once the inner most piston is
pushed past the by-pass channel without having allowed proper fluid
flow from the first chamber to the second chamber, it can be
extremely difficult to correct.
[0005] With some pharmaceutical constituents, in order to properly
constitute the pharmaceutical substance, it is desirable to ensure
that the mixing of the two constituents occurs slowly and
evenly.
SUMMARY OF THE INVENTION
[0006] It is an object of the present invention to provide a method
and a device which allows the mixing of two constituents of a
pharmaceutical substance and which overcomes the above drawbacks in
prior art devices.
[0007] According to one aspect of the present invention, there is
provided a device for mixing a substance comprised of two
constituents, the device comprising a cartridge, a cartridge
holder, a tubular container having a fluid communication end and an
actuation end, the fluid communication end being receivable in the
cartridge holder, the tubular container having a first closure
member disposed at the fluid communication end, a second closure
member disposed at the actuation end, a piston within the container
intermediate the first and second closure members, and a by-pass
channel for enabling fluid to by-pass the piston when the piston is
in the by-pass position, a plunger rod engageable with the second
closure member for moving the second closure member within the
container, the plunger rod having a rack gear formed thereon, a
housing, a pinon gear mounted within the housing, the pinon gear
being engageable with the rack gear, and a handle connected to the
pinion gear.
[0008] The transfer device of the present invention may be utilized
with any suitable by-pass type cartridge or container. Many such
by-pass cartridges or containers are known in the art.
Conventionally, the second closure member is screw threadedly
connectable to the plunger rod.
[0009] Utilizing the transfer device of the present invention
significantly reduces the possibility of the piston moving past the
by-pass channel prior to transfer of the diluent to the chamber
containing the active ingredient. In other words, it becomes
difficult to rapidly move the second closure at the actuation
end.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Having thus generally described the invention, reference
will be made to the drawings illustrating an embodiment thereof, in
which:
[0011] FIG. 1 is a partially exploded perspective view of a device
according to the present invention;
[0012] FIG. 2 is a side elevational view of the device;
[0013] FIGS. 3A, 3B and 3C are side sectional view illustrating
operation of the device;
[0014] FIG. 4 illustrates the detachment of the cartridge holder
from the housing; and
[0015] FIG. 5 illustrates a pen injector utilizing the cartridge of
the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0016] Referring to the drawings in greater detail and by reference
characters thereto, there is illustrated an assembly generally
designated by reference numeral 10 and which assembly 10 includes a
cartridge 12. Cartridge 12 is of a substantially conventional
structure and includes an activation end 16 and a fluid
communication end 14. A first closure member 18 seals fluid
communication end 14 while a second closure member 20 seals
activation end 16.
[0017] Situated interiorly of the cartridge 12 and intermediate
closure members 18 and 20 is a plunger 22 which divides the
cartridge into a first chamber 26 and a second chamber 28. As is
known in the art, a by-pass 24 provides fluid communication between
first chamber 26 and second chamber 28. Normally, first chamber 26
will carry the dry pharmaceutical component to be reconstituted
while second chamber 28 normally will carry a liquid diluent.
Naturally, other arrangements such as two liquids can be
utilized.
[0018] At it upper end (fluid communication end) cartridge 12 has a
shoulder 30.
[0019] Cartridge holder 32 surrounds cartridge 12 and has screw
threads 31 at its lower end. A shoulder 36 of cartridge holder 32
abuts shoulder 30 of cartridge 12.
[0020] A cap 38 having screw threads thereon is arranged to fit on
fluid communication end 14 of cartridge 12. Cap 38 includes a
piercing member 40 which has a passageway 43 therein. A gas
permeable hydrophobic membrane 41 is secured to the top of cap 38
and covers passageway 43.
[0021] Assembly 10 includes a pair of half housings 42 and 44 which
are secured together. At their upper ends, housings 42 and 44 have
external threads 45 designed to engage with threads on the inner
bottom wall of cartridge holder 32.
[0022] Interiorly of housing 42, 44 is a plunger rod 46 which has a
rack gear 48 formed on one side thereof. Rack gear 48 is designed
to engage with a pinon gear 50. A gear retainer 52 is formed on one
side of housing 44 while a wheel 54 is arranged to drive pinon gear
50.
[0023] In operation, and as may be seen in FIGS. 3A to 3C, housing
42, 44 is screw threadedly engaged with cartridge holder 32. At
this point in time, plunger rod 46 abuts closure member 20.
Operation of wheel 54 will cause movement of plunger rod 46 which
will then advance closure member 20 which in turn causes pressure
to advance plunger 22 to the position shown in FIG. 3B wherein it
is located at by-pass 24. Continued slow and steady advancement
will then cause the diluent in second chamber 28 to enter first
chamber 26 until closure member 20 abuts plunger 22. The two
components in chambers 26 and 28 are then mixed; any air present is
evacuated through passageway 43 in piercing member 40 while the
liquid is retained due to hydrophobic membrane 41.
[0024] When fully mixed, cartridge holder 32 can be unscrewed from
housing 42, 44 and is then attached to a pen injector 56 in a
conventional manner as shown in FIGS. 4 and 5.
[0025] It will be understood that the above described embodiments
are for purposes of illustration only and that changes and
modifications may be made thereto without departing from the spirit
and scope of the invention.
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