U.S. patent number 3,636,950 [Application Number 04/775,726] was granted by the patent office on 1972-01-25 for disposable cartridge for admixing two components of injectable medicament.
This patent grant is currently assigned to American Home Products Corporation. Invention is credited to Eloy A. Gomez, Stephen W. Goodsir, Dominic A. Marrocco.
United States Patent |
3,636,950 |
Gomez , et al. |
January 25, 1972 |
DISPOSABLE CARTRIDGE FOR ADMIXING TWO COMPONENTS OF INJECTABLE
MEDICAMENT
Abstract
A cartridge unit for use in, or as a syringe, and comprising two
chambers, each for containing a separate component of the final
injectable mixture, wherein one of said chambers is detachably
mounted on the unit, the other chamber is provided in the unit, and
means are provided for communicating said two chambers and then
causing the contents of the removable chamber to be introduced into
the other chamber, whereafter the detachable chamber is removed to
permit attachment of a push rod to the plunger or stopper when the
unit is to be used.
Inventors: |
Gomez; Eloy A. (Frazer, PA),
Goodsir; Stephen W. (King of Prussia, PA), Marrocco; Dominic
A. (Springfield, PA) |
Assignee: |
American Home Products
Corporation (New York, NY)
|
Family
ID: |
25105297 |
Appl.
No.: |
04/775,726 |
Filed: |
November 14, 1968 |
Current U.S.
Class: |
604/416;
604/88 |
Current CPC
Class: |
A61M
5/002 (20130101); A61M 5/284 (20130101); A61M
5/24 (20130101); A61M 5/1782 (20130101); A61M
5/282 (20130101); A61M 5/2459 (20130101) |
Current International
Class: |
A61M
5/28 (20060101); A61M 5/24 (20060101); A61M
5/00 (20060101); A61m 005/00 () |
Field of
Search: |
;128/218,218M,218N,218NV,218.1,218.1P,272,220,218R,218D,218P |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
577,611 |
|
Jun 1933 |
|
DD |
|
848,081 |
|
Sep 1952 |
|
DT |
|
Primary Examiner: Reich; Joseph S.
Claims
We claim:
1. A cartridge unit assembly adapted for selectively maintaining
separately or admixing two components of a medicament composition,
said assembly comprising:
a. a rigid tubular member forming the main body of said assembly
and providing a first chamber adapted to contain a first component
of a medicament and having a distal closed end and a proximal open
end;
b. a reciprocable stopper, having a peripheral surface and
positioned in said tubular member and sealing a portion of said
first chamber including said proximal end thereof, said stopper
having an axial bore therein extending inward from the proximal
region of said stopper and being closed by a penetrable area in the
distal region thereof;
c. a bushing, means mounting said bushing in said proximal open end
of said tubular member, said bushing having an opening at its
proximal end and having a transverse web at its distal end provided
with a centrally located aperture therein;
d. a sack reciprocably mounted in said bushing and having a portion
thereof extending from the proximal end of said bushing, said sack
defining a second chamber adapted to contain a second component of
a medicament, having a penetrable membrane closing the distal
region thereof, and being provided with means for ejecting the
contents of said second chamber;
e. a double-pointed cannula mounted in said bushing and having the
proximal end thereof extending proximally interiorly of said
bushing and terminating adjacent said penetrable area of said sack,
and having the distal end thereof extending distally within said
axial bore in said stopper and terminating adjacent the penetrable
distal area of said stopper, said double-pointed cannula having
stop means affixed thereto and positioned interiorly of said
bushing, first and second abutment means mounted in said bushing
distally and proximally of said stop means, respectively, for
limiting both distal and proximal reciprocation of said
double-pointed cannula within said bore of said stopper upon
engagement of said stop means with said first and second abutment
means, respectively, said first and second abutment means retaining
said stop means within said bushing;
f. complementary connecting means provided in said bore in said
stopper and on said transverse web of said bushing for removable
attaching said bushing to said stopper.
2. A cartridge unit assembly as defined in claim 1, wherein said
sack is provided with a resiliently collapsible wall.
3. A cartridge unit assembly as defined in claim 1, wherein stop
means are provided on said bushing for abutment with the proximal
end of said member for limiting distal entry of said bushing in
said member.
4. A cartridge unit assembly as defined in claim 1, wherein said
connecting means comprise:
a stud which is mounted in said stopper, has an axial bore
therethrough, and has a male screw thread on at least the proximal
region thereof, and
said centrally located aperture of said bushing has a female screw
thread therein.
5. A cartridge unit assembly as defined in claim 1, wherein said
first abutment means comprises a stud mounted in said stopper and
said second abutment means comprises the distal end of said sack,
and wherein said stop means affixed to said double-pointed cannula
abuts, in the extreme distal reciprocation of said double-pointed
cannula, with the proximal end of said stud mounted in said stopper
and in the extreme proximal reciprocation of said double-pointed
cannula, with the distal end of said sack.
6. A cartridge unit assembly as defined in claim 1, wherein said
connecting means comprises a female screw-threaded bore in said
stopper and a male screw-threaded nipple mounted on said bushing,
said nipple having an axial bore therethrough communicating with
said centrally located aperture in said bushing.
7. A cartridge unit assembly as defined in claim 6, wherein said
cannula stop means comprises a piston affixed to said
double-pointed cannula reciprocably mounted in a distally located
axial bore in said sack, and wherein said first abutment means
comprises restriction means located in the distal region of said
bore, and wherein said second abutment means comprises said
penetrable membrane of said sack which closes the proximal end of
said bore, and said piston abuts, in the extreme distal
reciprocation of said double-pointed cannula, with said restriction
means, and in the extreme proximal reciprocation of said
double-pointed cannula, with said penetrable membrane of said sack.
Description
BACKGROUND OF THE INVENTION
This invention relates generally to hypodermic syringes, and more
particularly to a cartridge unit, ampule-needle assembly, or the
like, adapted for admixing two different components contained
separately in sealed compartments thereof prior to use, whereby a
sterile therapeutic mixture or composition may be injected as
desired.
In many instances, it is necessary that, preparatory to injecting
certain therapeutic mixtures or compositions, the different
components thereof, which may be unstable when mixed, are
maintained separately until used. In other instances, it is
necessary to reconstitute a drug, which is preferably stored in dry
form, by dissolving or suspending it in a liquid medium.
Conventional devices for accomplishing the foregoing purposes
usually include at least two separate compartments, each of which
contains one of the components of the therapeutic composition. Just
before injection of the therapeutic composition comprising the
mixed components is to be made with the device, said components are
admixed in situ. Obviously, such mixing must be done in a sterile
manner without loss of either component to assure the required
proportions, and hence, potency of the medicament to be injected.
This is usually accomplished by one of a number of generally known
expedients. For example, the mixing may be brought about (a) by at
least partially removing a common wall or partition provided
between two chambers, each containing one of the components; e.g.,
as disclosed in U.S. Pat. No. 2,636,493 and U.S. Pat. No.
2,766,766; (b) by the breaking of a separating wall or membrane
upon application of hydrostatic pressure; e.g., as in U.S. Pat. No.
3,351,058 and U.S. Pat. No. 2,708,438; or (c) by elaborate valving
arrangements; e.g., as disclosed in U.S. Pat. No. 3,326,215 and
U.S. Pat. No. 2,665,687; and also (d) by providing for the piercing
of a chamber-separating wall or membrane by a cannula needle; e.g.,
as in U.S. Pat. No. 3,098,483 and U.S. Pat. No. 3,327,710.
Generally, such devices of the various types exemplified in said
patents are either complicated in structure, bulky, cumbrous and/or
do not permit facile attachment of a push rod to the stopper or
plunger of the cartridge unit at the time of use.
SUMMARY OF THE INVENTION
In view of the foregoing, it is an object of the present invention
to provide a new and improved cartridge unit for containing two
separate components in two separate compartments to assure that
there is no mixing together of said components until the desired
time.
It is another object of the present invention to provide a
cartridge unit possessing the desired advantages of segregated
storage, mixing and injection capability.
A further object of the invention is to provide a new and improved
cartridge unit of the type described, wherein the separate
components are initially maintained in separately sealed chambers
and may be rapidly and thoroughly mixed together at the desired
time without exposing the chambers externally, thus eliminating the
possibility of spillage or contamination of the components both
before and after mixing.
Another object of the invention is to provide such a cartridge unit
wherein one chamber thereof may be detachably mounted on the unit,
whereby, after the contents thereof is transferred to the chamber
which is permanently provided in the unit, said one chamber may be
removed to permit insertion of the unit into a syringe and
attachment of the plunger rod of the latter to the stopper of the
unit, which may then be used for injection.
It is another object of the present invention to provide such a
cartridge unit which may be used in a syringe or as a fully
disposable syringe per se.
It is yet another object of the invention to provide such a
cartridge unit wherein commercially available ampule-needle
assemblies comprising a single chamber for medicament may readily
be modified to obtain the two chambered mixing structure of the
invention.
Still another object of the invention is to provide such a
cartridge unit wherein, subsequent to the mixing operation, the
modifying structure is removable, whereby a commercially available
ampule-needle assembly may then be used in its usual manner.
It is another object of the present invention to provide such a
cartridge unit wherein at least one wall of the detachably mounted
chamber thereof is formed of a flexible material so that when
pressure is applied thereto (i.e., when the internal volume is
decreased by compressing said one wall) the removable chamber is
caused first to communicate with the second chamber containing a
second component of the composition, and thereafter, the component
in the removable chamber is caused to be transferred to said second
chamber.
The foregoing, and other features, objects and advantages of the
present invention are attained by the provision of a new and
improved cartridge unit wherein there is provided a rigid tubular
member forming the main body of the assembly and providing a first
chamber having a distal closed end and a proximal open end. A
reciprocable stopper is positioned in said tubular member and seals
off a portion of the first chamber including the distal end
thereof. In a preferred embodiment of the invention, a stud is
anchored in the stopper and extends axially thereof with a portion
protruding therefrom toward the proximal end of the first chamber
and the distal end directed towards a penetrable area of the
stopper. The stud has an axial channel extending completely
therethrough wherein there is positioned, for axial movement
therein, a cannula, which has a piercing point at either end, and
is hereinafter referred to as a "double-pointed cannula." The
double-pointed cannula has the distal end thereof located adjacent
the penetrable area of the stopper. The cannula has a laterally
projecting element affixed thereto at the proximal end thereof
which is normally positioned proximally away from the proximal end
of the stud and is adapted to limit the distal movement of the
cannula in the axial chamber upon abutment of the laterally
projecting element with the transverse web of the distal end of a
mounting bushing. The mounting bushing is removably positioned in
the proximal end of the rigid tubular body and has an aperture in
said web thereof through which the stud protrudes. Associated with
the aperture are connecting means for removably attaching the
bushing to the stud, thereby to prevent undesired movement of the
plunger when the chamber is depressed. Preferably, such connecting
means comprise a male screw thread on the proximal end of the stud
and a complementary female screw thread in the aperture in the web
of the bushing.
Positioned in the mounting bushing, which functions as a housing
therefor, is a movable sack providing a sealed chamber and having
at least one wall thereof which may move inwardly of the sack to
reduce the volume of the chamber provided thereby. The distal wall
of the sack is of a penetrable material, and when the sack is
positioned in the mounting bushing, said wall overlies the proximal
end of the double-pointed cannula.
In a preferred embodiment of the invention, the wall of penetrable
material is faced, at least in part, with a rigid portion which
functions to limit the distal travel of the sack in the bushing
when the laterally projecting element of the cannula and/or
proximal edge of the stud in the stopper is abutted by said rigid
portion. Preferably, the mounting bushing is provided at its
proximal end with a lateral projection extending outwardly of the
tubular body when mounted therein and functioning as a finger rest,
only during premanipulation of the cartridge unit for the mixing
operation as will appear hereinafter.
In another embodiment of the invention, the stud in the plunger is
omitted and, instead, the plunger is provided with an axially
disposed bore extending from the proximal surface of the plunger to
a point close to but not through the distal surface thereof. The
bore is provided with a female screw thread. The bushing, instead
of having an aperture provided with a female screw thread, has a
proximally disposed nipple having an axial bore completely
therethrough adapted to receive the distal end of the
double-pointed cannula. The outer surface of the nipple is provided
with a male screw thread complementary to the female screw thread
of the bore of the plunger, whereby the bushing may be removably
connected to the plunger. In this embodiment, the removable sack is
preferably provided with a neck at the distal end in which there is
an axial bore, in this case, extending through the distal surface
of the neck but terminating at the proximal end thereof, which is
closed by a transverse web of penetrable material functioning as a
seal for the chamber in the removable sack. The bore has a diameter
to permit reciprocation therein of a piston permanently affixed to
the proximal region of the double-pointed cannula. The distal end
of the bore has a restriction therein defining a reduced diameter
which permits reciprocation of the double-pointed cannula
therethrough but functions as a stop for the piston affixed
thereto, thus limiting distal reciprocation of the cannula-piston
assembly. Reciprocation of said assembly in the proximal direction
is limited by abutment of the piston with the proximal transverse
web of the bore, after the proximal end of the double-pointed
cannula has penetrated said web.
The nature of the invention will more readily appear on a reading
of the descriptions of several preferred embodiments thereof set
forth below, with reference to the drawings wherein:
FIG. 1 is a side elevational view of a cartridge unit assembly
embodying the invention, with portions of the structure broken away
to disclose the contents of the sack and tubular barrel and the
interior structures of the ferrule and cannula assembly;
FIG. 2 is an exploded view of the proximal portion of the assembly
illustrated in FIG. 1;
FIG. 3 is an axial cross section of the assembly shown in FIG. 1,
taken on line 3--3 thereof;
FIG. 4 is a side elevational view of a modification of the unit of
FIGS. 1-3, wherein the sack, cannula, and bushing assembly is
omitted, and instead, there is a removable cover positioned in the
proximal open end of the unit, and a dual purpose cannula guard and
push rod is attached to the distal end of the unit; and
FIG. 5 is a vertical cross section of the proximal end of the unit
disclosed in FIG. 4, with the cover removed and a bushing and
modified sack and needle assembly inserted therein.
Referring now to the drawings, and particularly FIGS. 1, 2, and 3,
the cartridge unit disclosed therein comprises a tubular barrel 2
to which is affixed, on a distal neck 2a thereof, a plastic ferrule
or hub 3 and a metal injection cannula 4. As will be recognized by
those skilled in the art, ferrule 2 may, alternatively, be of
metal, as is conventional and shown, for example, in U.S. Pat. No.
2,671,450. Cannula 4 is provided with a removable cannula sheath 5
of rubber which is frictionally mounted on a distal portion 3a of
ferrule 3, to encase cannula 4, as also appears in said patent.
Sealingly mounted within barrel 2, but reciprocally movable
therein, is a resilient plunger or stopper 7 having a stud 8
anchored axially therein with the proximal end 9 thereof protruding
from said plunger 7. Said stud 8 has a male screw thread 9a thereon
adapted for selective attachment thereto of a plunger rod of a
syringe, not shown, but which may be of the structure disclosed,
for example, in U.S. Pat. No. 2,671,450. Tubular barrel 2 per se,
the plunger 7 therein, and neck 2a at the distal end of barrel 2,
enclose a first chamber 10 in which may be contained the first
component 40, which may be a solid or liquid, of the
medicament.
Positioned in the proximal end 2b of tubular barrel 2 is a bushing
14 of plastic. Bushing 14 has, at the distal end thereof, a
transverse web 14a within which is centrally provided a
female-threaded aperture 14b of a diameter to permit attachment of
said bushing 14 screw threadedly on the complementary male thread
9a provided on the proximal end 9 of stud 8, as best seen in FIG.
3. The proximal portion 14c of bushing 14 is of a larger diameter
than the remainder thereof and is connected to the latter by an
annular extension 15 which functions as a limiting stop with
respect to the insertion of bushing 14 in barrel 2 upon abutment of
said extension 15 with the edge 2c of the proximal end 2b of barrel
2. Annular extension 15 serves also as a finger rest when the
device is being utilized in the mixing operation, as referred to in
greater detail hereinafter.
In accordance with this preferred embodiment of the present
invention, stud 8 has an axial bore 11 completely therethrough.
Positioned for reciprocation in said bore 11 is a double-pointed
cannula 12. As assembled (i.e., prior to use of the device in the
mixing operation) and as appears in FIG. 3, the distal end 12a of
cannula 12 is positioned adjacent a pierceable area 7a located at
the distal end of plunger 7. The proximal end 12b of the
double-pointed cannula 12, on the other hand, protrudes beyond the
proximal end 9 of stud 8 and hence within bushing 14 when the
latter is attached to stud 8. At said proximal end 12b, cannula 12
has axially affixed thereto a laterally projecting disk 13, which
is positioned proximally of web 14a of bushing 14. The diameter of
disk 13, as shown, is greater than that of the centrally located
aperture 14b in web 14a of bushing 14 and substantially that of the
interior of bushing 14 for purposes which will also appear
hereinafter.
Positioned in bushing 14 is a sack 16 which encloses a second
chamber 17 containing a second component 42, which may be a solid
or a liquid, of the medicament to be mixed with the first component
40 in the first chamber 10. Sack 16 is provided with a distal
surface 18, which, in this instance has been sealed at reentrant
area 18a after the liquid has been introduced into chamber 17. Said
area 18a is penetrable by the proximal end 12b of double-pointed
cannula 12, as referred to hereinafter.
Sack 16 is provided at the proximal region of its circumferential
surface with bellows folds 20, whereby, upon suitable pressure on
the proximal end 16a of sack 16, said region may be collapsed,
thereby to reduce the volume of the second chamber 17 provided
therein which contains the second component 42.
In the assembly of the conventional cartridge portion of the
embodiment of the invention just described, plastic ferrule 3 and
metal cannula 4 may be permanently mounted on the distal neck end
2a of the tubular barrel 2, as described, for example, in U.S. Pat.
No. 3,278,357. Cannula 4 may be provided with a cannula sheath 5,
manually, or by a device described, for example, in U.S. Pat. No.
3,188,727. Thereafter, the first component 40 of the medicament is
introduced into first chamber 10 in barrel 2, and plunger 7 may be
inserted into barrel 2 by apparatus described, for example, in
Serial No. 513,136 filed Dec. 10, 1965, which has matured into U.S.
Pat. No. 3,391,518.
Alternatively, if desired, ferrule 3 may be of metal and attached,
with the cannula affixed thereto previously to barrel 2, by
apparatus described, for example, in U.S. Pat. No. 3,247,641. In
this alternative assembly, the procedural steps are quite
different. Thus, the plunger 7 is inserted first; then, with the
tubular barrel 2 inverted so that the open end thereof faces
upwardly, the contents of the first chamber 10 may be introduced,
and thereafter the assembly consisting of ferrule 3 and cannula 4
may be crimpingly attached to the tubular barrel 2, as by said
apparatus of U.S. Pat. No. 3,247,641.
As will appear to those skilled in the art, the modes of the
assembly of the parts described immediately above form no part of
the present invention, and may be varied as found desirable.
Reverting now to the assembly of the above desired embodiment of
the mixing structure of the present invention, double-pointed
cannula 12, with disk 13 affixed thereto, is first inserted via the
open proximal end of bushing 14 into the distal region thereof.
Disk 13 riding within bushing 14 functions as positioning means for
double-pointed cannula 12 so that the distal end 12a of the latter
protrudes through aperture 14b in web 14a of bushing 14, while the
proximal end 12b of cannula 12 with the disk 13 affixed thereto is
positioned within the distal end of bushing 14. Thereafter, sack
16, which already contains the second component 42 of the
medicament sealed in the second chamber 17 thereof as referred to
before, is introduced into said bushing 14, whereby the surface 18
of sack 16 faces distally towards the proximal end of web 14a of
bushing 14, but is spaced therefrom to avoid penetrating abutment
of penetrable area 18a with the distal end 12b of double-pointed
cannula 12, for a purpose which will also appear presently.
As part of the assembly of this embodiment of this invention,
bushing 14, with double-pointed cannula 12 and sack 16 positioned
therein as just described, is next inserted into the proximal end
2b of barrel 2. As the distal end of said assembly is inserted into
barrel 2, double-pointed cannula 12 is maintained in position by
disk 13 bearing within bushing 14 so that distal end 12a of
double-pointed cannula 12 is aligned with bore 11 of stud 8 and
enters said bore. Said assembly is inserted further into barrel 2
until the portion of web 14a of bushing 14 which surrounds
screw-threaded aperture 14b thereof abuts the proximal edge 9 of
stud 8. Bushing 14 is then rotated for screw threadedly attaching
it to stud 8 by means of said screw-threaded aperture 14b and
complementary male screw thread 9a of stud 8. Rotation of bushing
14 is continued until annular extension 15 thereof abuts edge 2c of
tubular barrel 2. In such arrangement of the parts, double-pointed
cannula 12 is positioned within bore 11 of stud 8 with the distal
end 12a thereof located adjacent penetrable area 7a of plunger 7,
and plunger 7 is retained against any inadvertent reciprocal
movement.
Just prior to the use of the device by the doctor, nurse, or other
party performing the injection of medicament into the patient, sack
16 may be urged distally in bushing 14, until area 18a of sack 16
abuts the proximal end 12b of double-pointed cannula 12 and begins
to urge it distally in bore 11 of stud 8 until the distal end 12a
of double-pointed cannula 12 abuts area 7a of plunger 7. As sack 16
is urged further distally in bushing 14, and depending upon the
relative penetrability characteristics of area 18a and 7a, first
one and then the other of said areas is penetrated by the
respective ends 12b and 12a of double-pointed cannula 12. As will
be understood, during these operations, plunger 7 is maintained
substantially in the position shown in FIG. 3, because of the
attachment of stud 8 thereof to bushing 14 as described above.
Regardless of the sequence of penetration, when sack 16 is
ultimately pressed home within bushing 14, area 18a of sack 16 is
fully pierced by the proximal end 12b of double-pointed cannula 12,
area 7a of plunger 7 is fully pierced by the distal end 12a of
double-pointed cannula 12, and the laterally projecting disk 13 on
double-pointed cannula 12 is abutted on its proximal surface, by
the distal surface of web 18 of sack 16, and on its distal surface
by the proximal end 9 of stud 8. In such relationship of parts,
said first chamber 10 in tubular barrel 2 is in communication with
second chamber 17 in sack 16 via double-pointed cannula 12.
Finger pressure is next applied to proximal end 16a of sack 16 to
reduce the volume of second chamber 17 therein and hence to force
the second component 42 thereof through double-pointed cannula 12
into first chamber 10 in tubular barrel 2 containing the first
component 40 of the medicament. The entire device may be shaken
manually or otherwise agitated to cause appropriate mixing of the
second component 42 with the first component 40 in chamber 10.
Subsequently to the mixing operation, bushing 14 is unscrewed from
stud 8, and thereafter is lifted out of the proximal end 2b of
tubular barrel 2, to carry therewith both sack 16 and
double-pointed cannula 12.
At the time of use for actual injection, the cartridge unit
comprising tubular barrel 2, ferrule 3, cannula 4, cannula sheath
5, plunger 7, and the mixed medicament in chamber 10, may simply be
inserted into a syringe of the type described in U.S. Pat. No.
2,671,450, referred to hereinbelow and the plunger push-rod of said
syringe screw threadedly attached to stud 8 of plunger 7.
Thereafter, as is conventional, cannula sheath 5 may be removed to
uncover cannula 4 and the device utilized for the usual injecting
operation, including aspiration, as desired.
In the embodiment of the invention disclosed in FIGS. 4-5, the
barrel, ferrule and cannula structures are substantially identical
to those of the embodiment disclosed in FIGS. 1-3, with the
exceptions noted hereinafter. Accordingly, said substantially
identical structures in FIGS. 4-5 are indicated by the same, but
primed reference numerals. The structural and operational
differences of the embodiment of FIGS. 4-5 when compared with that
of FIGS. 1-3 will appear from the following description of the
former.
As disclosed in FIG. 4, a cannula guard 6 is mounted on ferrule 3'
(FIG. 5) by means of the male screw thread 3'b on the latter and a
complementary female screw thread within a first bore (neither of
which screw thread or bore is visible in FIG. 4) in the proximal
end 6a of cannula guard 6, thereby to cover the cannula sheath 5'
of cannula 4' (FIG. 5). The general relationship of the cannula
guard 6 to the remaining structure described hereinbefore is
conventional and is disclosed in detail, for example, in U.S. Pat.
No. 2,671,449. The single notable exception to the cannula guard 6
structure shown in said patent is that, in the present instance,
instead of there being provided in the distal end of said guard 6 a
second bore having a female screw thread therein adapted for
attachment to a stud on the plunger 7', there is provided, on said
distal end of guard 6, a nipple 6b having a male screw thread 6c
thereon for a purpose which will later appear.
A further and more important distinction of the FIGS. 4-5
embodiment from that depicted in FIG. 1-3 is that, in the former,
the plunger 7', the bushing 14', the sack 16', and the
double-pointed cannula 12' have modified structures now
described.
Primarily, plunger 7' is not provided with a stud. Instead, plunger
7' is provided with an axial bore 28, in which is a female screw
thread 29. The latter is complementary to the male screw thread 6c
on nipple 6b of cannula guard 6. However, the distal end of bore 28
is closed by a penetrable area 7'a of plunger 7'.
Bushing 14' does comprise an annular extension 15' at its proximal
end. However, at its distal end, it is not provided with a female
threaded aperture 14b in transverse web 14'a thereof. Instead web
14'a is provided with a distally disposed nipple 30 which has
axially therethrough a bore 30a and, on its peripheral surface, a
male screw thread 30b. Male screw thread 30b is also complementary
to female screw thread 29 of bore 28, whereby nipple 30 may be
removably attached to plunger 7' as shown in FIG. 5.
Mounted in bushing 14' is a sack 16' which, in this instance, has
the general configuration of an inverted plastic bottle, the neck
16'b of which is provided with an axial bore 24. Sack 16' encloses
a chamber 17' which contains the second component 42 of the
medicament to be injected. Bore 24, at its proximal end is
separated from chamber 17' of sack 16' by a penetrable web 18'a. At
the distal end of bore 24, there is affixed a restriction cap 21
which defines a smaller diameter opening 31 through which
double-pointed cannula 12' reciprocates. Affixed adjacent to the
proximal end 12'b of cannula 12' is a piston 13' which is
reciprocably mounted within bore 24. As will be apparent from FIG.
5, piston 13' functions as a stop which limits reciprocation of
double-pointed cannula 12' distally when said piston 13' engages
with web 18'a, and proximally upon engagement of piston 13' with
restriction cap 21.
In the assembly of sack 16' per se, the chamber 17' of the latter
is filled with the second component 42 and sealed. Double-pointed
cannula 12' with piston 13' affixed is next inserted in bore 24 of
neck 16'b. Thereafter, restriction cap 21 is pressed over distal
end 12'a of cannula 12 and sealed to the distal end of neck
16'b.
As a further distinction of this modified embodiment of the
invention, bushing 14', sack 16', and cannula 12' may be provided
to the ultimate user as a unit assembly separately of the cartridge
unit comprising tubular barrel 2', stopper 7', ferrule 3', cannula
4', sheath 5', and guard 6. In such case, the distal end 12'b
protruding from bore 30a in nipple 30 of bushing 14' may be covered
by a cap (not shown) removably mounted on nipple 30 by means of a
complementary female screw thread, and sack 16' may be paper or
plastic sealed (not shown) in bushing 14' . Also for purposes of
sterility, there is provided in the proximal end 2'b of tubular
barrel 2', a removable cover 51 which is frictionally seated in the
proximal end 2'b of barrel 2, as shown in FIG. 4. Cover 51 has a
peripheral lip 51a overlying edge 2'c of barrel 2', which edge, in
this case, is in the form of a bead 2d. The latter functions to
retain an annular finger piece 52, in a manner also disclosed in
said U.S. Pat. No. 2,671,449.
In the use of the embodiment disclosed in FIGS. 4-5, cover 51 is
removed from tubular barrel 2'; the cap, if provided on nipple 30
of bushing 14' is removed to expose the distal end 12'a of cannula
12'; and, again if provided, the seal of the sack 16' to the
bushing 14' is broken. Thereafter, the user inserts the aforesaid
unit assembly of bushing 14', sack 16' and double-pointed cannula
12' into the proximal end 2'b of barrel 2' and then screws nipple
30 of bushing 14' into the bore 28 of plunger 7' by means of the
complementary screw threads 30b and 29, respectively (FIG. 5).
In the mixing operation, the sequence of manipulation is generally
similar to that described with respect to the embodiment in FIGS.
1-3. Specifically, the sack 16' is first pressed home in bushing
14' until double-pointed cannula 12' penetrates both web 18'a of
sack 16' and the penetrable area 7'a of plunger 7'. Thereafter,
pressure on (or squeezing of) the distal end 16'a of sack 16'
forces the first component 40 in chamber 17' thereof through
double-pointed cannula 12' and into chamber 10' in tubular barrel
2' containing the second component 42 of the medicament. As in the
previous embodiment, mixing as by agitation may be undertaken,
followed then by removal of the bushing 14', sack 16' , and
double-pointed cannula 12' assembly by first unscrewing nipple 30
of bushing 14' from bore 28 in plunger 7' and thereafter lifting
said entire assembly out of barrel 2' as a unit.
In the ultimate use of this embodiment of the invention for
hypodermic injection, cannula guard 6 is unscrewed from ferrule 3'
to expose sheath 5' which covers cannula 4' (as shown in FIG. 5).
Cannula guard 6 is then attached to plunger 7' by means of the
complementary screw-threaded nipple 6b of the former and bore 28 of
the latter. With the parts in such assembly, cannula sheath 5' may
be removed to expose cannula 4' and the cartridge unit used as a
completely disposable syringe per se by utilizing the finger piece
52 in grasping barrel 2' while the thumb of the user is positioned
on the proximal end 6a of cannula guard 6 which now functions as a
push rod in the manner described in the aforesaid U.S. Pat. No.
2,671,449.
It will, of course, be understood that, although two specific and
preferred embodiments of the invention have been described above in
detail, many changes and modifications may be made, and said
invention embodies in widely differing forms, without departing
from the spirit and scope thereof, in its broader aspects coming
within the language or scope of any one or more of the appended
claims. Merely by way of example, the several parts may be made of
various materials, such as glass, plastics, rubber or metal as
desired; other ferrule-cannula assemblies may be utilized, or
omitted; other finger piece, cannula sheath and/or guard assemblies
may be employed, or omitted; the screw threads may be replaced by
other connecting means, such as bayonet, ball and socket, or other
frictional attachment means; the double-ended cannula may be
provided with stop means other than the disc and piston shown; the
bushing and the sack may be provided with complementary screw
threads whereby the sack may be screwed into the bushing rather
than pushed thereinto; the sack may be rigid and be provided with
other volume reducing means, such as a piston; etc. Other
variations, including interchange of specific element structures
and/or assemblies, in the embodiments disclosed, will suggest
themselves to those skilled in the art.
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