Note: Descriptions are shown in the official language in which they were submitted.
CA 02686433 2009-11-20
DOUBLE PUSH INJECTION DEVICE
FIELD OF THE INVENTION
The present invention relates to a medical device and more particularly,
relates to a
reconstitution and injection system.
BACKGROUND OF THE INVENTION
As is well known in the art, many drugs are desirably stored as two separate
components. The components are typically a dry component and a diluent
therefore,
although two liquid components could also be utilized. The advantages of
storing one of the
components in a dry form is that a greater shelf life is provided. Ideally,
the drug and a
diluent are mixed immediately prior to injection.
Although there are many different systems for reconstituting a drug by mixing
a dry
and a liquid component, such systems are relatively complex and expensive.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a reconstitution and
injection system
wherein both the reconstitution and injection can be done using the same
device.
According to one embodiment of the present invention, there is provided a
reconstitution injection system which comprises a housing having a front end
and a rear end,
a first cartridge containing a first substance, the first cartridge being
located within the
housing, the first cartridge having a first cartridge plunger and a first
cartridge septum, a
second cartridge containing a second substance, the second substance being
located within
the housing rearwardly of the first cartridge, the second cartridge having a
second cartridge
plunger and a second cartridge septum, a first needle hub intermediate the
first and second
cartridges, a first needle being mounted within the first needle hub, the
first needle having
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CA 02686433 2009-11-20
both first and second piercing ends, a second needle hub located forwardly of
the first
cartridge, a second needle mounted in the second needle hub, the second needle
having first
and second piercing ends, a first biasing member mounted within the housing,
the first
biasing member being located forwardly of the second cartridge and being
operative to bias
the second cartridge rearwardly, and a plunger rod assembly securable to the
second cartridge
plunger.
BRIEF DESCRIPTION OF THE DRAWINGS
Having thus generally described the invention, reference will be made to the
accompanying drawings, in which:
Figure 1A is an elevational view of a reconstitution and injection system
according to
an embodiment of the present invention:
Figures 1 B through 1 I are cross sectional views illustrating operation of
the system.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the drawings in greater detail and by reference characters
thereto, there is
illustrated a reconstitution and injection system which is generally
designated by reference
numeral 10.
Reconstitution injection system 10 includes a housing side wall 12 which is
generally
of a cylindrical configuration along with a distal end wall 14 and a proximal
end wall 16.
For purposes of this application, distal means the end used for injection
while proximal
means the opposite end or the end where a pushing force is applied. Distal end
wall 14 has a
nose 18 formed thereon through which a passageway extends. It will be noted
that there is
also provided an enlarged portion 20 of housing wall 12 proximate distal wall
14. Enlarged
portion 20 forms an ambutment wall 22.
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CA 02686433 2009-11-20
Mounted internally of housing wall 12 is a first container 24 which is of a
generally
cylindrical configuration and includes a neck portion 26. First container 24
also has a
plunger 28 located at the proximal end thereof and a septum 30 covering the
container
opening.
A second container 32 is situated forwardly of first container 24 and also has
a septum
34 and a plunger 36. It will be noted that the side wall defining second
container 32 extends
substantially past plunger 36 such that first container 24 is partially
located within the wall of
second container 32.
Mounted intermediate of first container 24 and second container 32 is a first
needle
hub 38 which includes a first needle 40 mounted therein. First needle 40 has a
first piercing
end 42 and a second piercing end 44.
Situated forwardly of first container 24 is a second needle hub 46 containing
a second
needle 48. Second needle 48 has a first piercing end 50 and an injection end
52. Second
needle hub 46 also includes a wall 47 which extends about the wall defining
second
container 32 and partially about first container 24.
A spring 54 is mounted within housing wall 12 forwardly of second needle hub
46
and is biased against second needle hub 46 and distal end wall 14.
For injection purposes and ease of handling, there are provided finger flanges
56 in a
conventional manner.
The reconstitution and injection system 10 also includes an outer plunger rod
58
which is screwthreadedly engaged with plunger 26 and an inner plunger rod 60
which is
mounted inwardly of outer plunger rod 58 and releasably retained therein. A
spring 62 is
mounted interiorly of outer plunger rod 58 and biases against inner plunger
rod 60.
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CA 02686433 2009-11-20
As shown in Figures 1 C and I D, pressure on plunger rods 58, 60 as shown by
arrow
64 will cause the movement of plunger 26 such that first needle 40 will pierce
plunger 36 of
second container 32 and septum 30 of first container 24. This will cause the
material within
first container 24 to transfer to second container 32. If desired, the device
may be shaken to
ensure proper reconstitution.
Continued pressure on plunger 28, as shown in Figure JE, will cause
compression of
spring 54 and permit the piercing of septum 34 by first piercing end 50 of
second needle 48.
Second end 44 will then extend exteriorly of the housing wall 20 through nose
18.
At this point in time, inner plunger rod 60 may be released from its inner
engagement
with outer plunger rod 58. Spring 62 will then bias inner plunger rod 60
outwardly of outer
plunger rod 58 as illustrated by arrow 66 in Figures IF. In so doing, inner
plunger rod 60 has
protrusions 68 which will lock with corresponding recesses formed in outer
plunger rod 58.
The device is now ready for injection as shown in Figure 1G.
Following injection, release of pressure on inner plunger rod 60 will permit
spring 54
to act on second container 32 to cause the retraction of needle 40 within
housing 12. One
may then safely dispose of the device.
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