U.S. patent number 3,714,943 [Application Number 05/093,982] was granted by the patent office on 1973-02-06 for medicament injectors.
This patent grant is currently assigned to SAID Yanof and Pansky, by said Poff. Invention is credited to Ben Pansky, James S. Poff, Howard M. Yanof.
United States Patent |
3,714,943 |
Yanof , et al. |
February 6, 1973 |
MEDICAMENT INJECTORS
Abstract
The specification and drawings disclose two embodiments of
medicament injectors of the type commonly referred to as "velocity
injectors." Both embodiments provide means by which the quantity of
medicament can be varied. Each embodiment also has a single valve
assembly which controls filling, cleaning, and firing. An important
aspect of one embodiment is the use of a rotatable multiple dosage
supply housing which can be sequentially indexed to bring
medicament ampules into proper relationship with the valve
assembly. In addition to the features noted above, the second
embodiment discloses an injector which automatically injects when
pressed against the patient.
Inventors: |
Yanof; Howard M. (Toledo,
OH), Pansky; Ben (Toledo, OH), Poff; James S.
(Findlay, OH) |
Assignee: |
SAID Yanof and Pansky, by said
Poff (N/A)
|
Family
ID: |
22242066 |
Appl.
No.: |
05/093,982 |
Filed: |
December 1, 1970 |
Current U.S.
Class: |
604/70; 604/71;
222/389; 604/191 |
Current CPC
Class: |
A61M
5/31551 (20130101); A61M 5/30 (20130101); A61M
2005/005 (20130101); A61M 5/19 (20130101); A61M
5/2053 (20130101); A61M 5/001 (20130101); A61M
5/2448 (20130101); A61M 5/1782 (20130101); A61M
2205/6081 (20130101) |
Current International
Class: |
A61M
5/30 (20060101); A61M 5/20 (20060101); A61M
5/19 (20060101); A61M 5/24 (20060101); A61M
5/178 (20060101); A61M 5/00 (20060101); A61m
005/30 () |
Field of
Search: |
;128/173H,218D,218DA,218A,218PA,218R,218P,215,214F,184
;222/144,144.5,130,389 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Gaudet; Richard A.
Assistant Examiner: Dunne; G. F.
Claims
What is claimed is:
1. A velocity type medicament injector comprising:
a first body portion including a medicament receiving chamber
having at least one orifice through which medicament can be
ejected, said chamber including at least one movable wall portion
through which pressure can be applied to medicament in said chamber
to cause it to be ejected through the orifice at a velocity
sufficient to enter tissue without use of a needle;
a second body portion connected with said first body portion and
including housing means carrying a plurality of fluid containers
and at least one propellant gas cartridge;
passage means including valve means connected between the housing
means and the first body portion to controllably supply fluid and
pressurizing gas to the chamber on opposite sides of the movable
wall; and,
indexing means for permitting movement of at least that portion of
the housing means which carries said plurality of fluid containers
relative to the first body portion to bring selected ones of said
fluid containers into flow relationship with said passage
means.
2. The injector as defined in claim 1 wherein said housing means is
mounted for rotation about a fixed axis.
3. The injector as defined in claim 1 wherein at least one of said
containers contains a cleaning solution which can be indexed into
alignment with the passage means for cleaning at least the
medicament receiving chamber.
4. The injector as defined in claim 1 wherein said orifice includes
means for permitting its diameter and number of orifices as well as
length to be varied.
5. The injector as defined in claim 1 wherein said movable wall
comprises a piston slidable in said medicament chamber and dividing
said medicament chamber into first and second chamber portions.
6. The injector as defined in claim 1 wherein said valve means is
carried in said first body portion and comprises a rotatable valve
member.
7. The injector as defined in claim 1 wherein said movable wall
means comprises a piston in said medicament chamber and wherein
said passage means includes a first passage for supplying
pressurized gas to one side of said piston and a second passage for
supplying medicament to the opposite side of said piston.
8. The injector as defined in claim 1 wherein said medicament
chamber includes means for adjusting the amount of medicament which
can be held in said chamber.
9. The injector as defined in claim 1 wherein the means for
adjusting the amount of medicament comprises means for limiting
movement of said movable wall portion.
10. The injector as defined in claim 1 wherein said carrier is
mounted for rotation about an axis and longitudinal movement along
said axis.
11. The injector as defined in claim 1 wherein said housing means
includes openings in which said containers are received, said
openings including means for opening said containers.
12. The injector as defined in claim 1 wherein said movable wall
includes a piston slidable in said medicament chamber and including
means for limiting the movement of said piston.
13. The injector as defined in claim 1 wherein said housing means
includes means for indicating the number of unused containers
carried therein.
14. The injector as defined in claim 1 wherein said orifice is
defined by a removable end wall on said chamber.
15. The injector as described in claim 7 wherein said valve means
comprises a single valve element controlling flow through between
said first and said second passage portions.
16. The injector as described in claim 7 wherein means are provided
for bleeding gas from said medicament chamber.
17. A velocity type medicament injector including a first housing
adapted to hold medicament and a propellant gas;
a second housing carried by said first housing and movable relative
thereto, said second housing including a medicament chamber having
a movable wall portion and an outlet orifice through which
medicament can be ejected;
passageway means for supplying medicament from said first housing
to said medicament chamber, said passageway means further including
a gas passageway extending through the second housing for supplying
pressurized gas from said first housing to a position behind the
movable wall portion; and,
means associated with said second housing to prevent gas from
flowing through said gas passageway except upon movement of the
second housing relative to the first housing in a direction toward
the outlet orifice.
18. The injector as defined in claim 17 wherein said second housing
is carried in said first housing and is slidable relative
thereto.
19. The injector as defined in claim 17 wherein said second housing
is slidable in said first housing and wherein said means to prevent
pressurizing gas from flowing through the passageway comprises
cooperating valve surfaces formed in said first and said second
housing portions.
20. The injector as defined in claim 17 including biasing means for
continually biasing said second housing to a position wherein gas
is prevented from flowing through said passageway.
21. The injector as defined in claim 17 wherein said medicament
chamber includes means for adjusting the amount of medicament which
can be held in said chamber.
22. The injector as defined in claim 17 wherein said movable wall
means includes means for selectively moving it to desired
positions.
Description
The present invention is directed toward the art of hypodermic
injectors and, more particularly, to improved injectors of the type
by which medicament can be injected without the use of a
skin-piercing needle.
The invention will be described with reference to certain preferred
embodiments; however, it will be apparent that the invention could
be embodied in many specific structural arrangements.
Hypodermic injectors which inject medicament by use of a high
velocity jet without a skin-piercing needle are well known and
often referred to as "velocity injectors." Such velocity injectors
are often used in mass innoculations. They have not, however, been
widely used for giving individual shots on a limited basis, such as
in doctors' and dentists' offices, or by diabetics in their
homes.
The primary reason velocity injectors have been limited to mass
innoculation type use has been their general complexity, bulkiness,
and high cost. Many attempts have been made to provide a simple,
compact, and inexpensive velocity injector. The prior attempts have
not been successful for many reasons. Typically, the simpler units
have not been capable of providing varying dosages except through
the use of medicament ampules in many sizes. For someone like a
diabetic whose dosage may change substantially from day-to-day
depending upon exercise and food intake, this would require
maintaining a large supply of ampules of differing sizes. Further,
the prior inexpensive units have been difficult to clean and
somewhat troublesome to load. An additional problem with many of
the prior units has been the possibility of insufficient velocity
on the medicament. This has been particularly true of those units
wherein the actuating pressure is supplied from a compressed gas
cartridge which is used for several shots. For example, if there
has been a substantial time period between shots, gas leakage can
cause reduction in pressure to a level wherein the next shot is not
given sufficient velocity. Alternately, in a series of shots, the
pressure of the gas cartridge is continually dropping so that the
velocity of each shot is less. Consequently, to be safe, it is
necessary to change gas cartridges relatively more often than
absolutely necessary.
The present invention overcomes the above-discussed problems and
provides a simple and highly reliable velocity injector. Injectors
formed in accordance with the invention are highly reliable,
compact, and safe to use.
In accordance with one aspect of the invention, there is provided
an injector having a first body portion including a medicament
receiving chamber and an orifice through which the medicament can
be ejected. The chamber includes at least one movable wall portion
through which pressure can be applied to medicament in the chamber
to cause it to be ejected through the orifice at a velocity
sufficient to enter tissues without use of a needle. Connected with
the first body portion is a second body portion including housing
means for carrying a plurality of medicament ampules and a
plurality of cartridges holding a propellant gas under substantial
pressure. Passage means including valve means connect between the
housing means and the first body portion to controllably supply
medicament and pressurizing gas to the chamber on opposite sides of
the movable wall. Additionally, indexing means are provided for
permitting movement of the housing means relative to the first body
to bring selected ones of said ampules and capsules into flow
relationship with the passages.
Preferably, but not necessarily, the housing means also includes a
container of cleaning solution which can be indexed into alignment
with the passage means for flushing at least the medicament
receiving chamber. Additionally, the housing means is preferably
rotatable relative to the first body portion and provided with
means for preventing inadvertent actuation of the cleaning
solution. Preferably, but not necessarily, the gas cartridge used
with the cleaning solution is under a pressure sufficiently low so
that injection cannot take place.
In accordance with a further aspect of the invention, there is
provided a velocity injector including a first housing adapted to
hold a medicament ampule and propellant gas cartridge. Carried by
the housing and movable relative thereto is a second housing
including a medicament chamber having a movable wall portion and an
outlet orifice through which medicament can be ejected. Means are
provided for supplying pressurized gas to a position behind the
movable wall portion including a passageway extending through the
second housing. Associated with the second housing are means to
prevent pressurizing gas from flowing through the passageway except
upon movement of the second housing relative to the first housing
in a direction toward the outlet orifice.
The arrangement of the housing portions is such that the user
merely presses the outlet against the skin causing movement of the
second housing relative to the first to thereby release pressurized
gas and produce an injection. It is not necessary to consciously
press an actuating lever, button, or the like. This is advantageous
for persons such as diabetics who must give themselves shots.
The above and other objects and advantages will become apparent
from the following description when read in conjunction with the
accompanying drawings wherein:
FIG. 1 is a longitudinal, cross-sectional view through a preferred
embodiment of injector formed in accordance with the invention;
FIG. 2 is a cross-sectional view taken on line 2--2 of FIG. 1;
FIG. 3 is a view taken on line 3--3 of FIG. 1 and showing the
actuating knob for valve assembly of the FIG. 1 embodiment;
FIG. 4 is pictorial view of a typical medicament or pressurizing
gas cartridge used in the preferred form of the invention;
FIG. 5 is a pictorial, somewhat schematic, showing of the rotary
slide valve assembly used in the FIG. 1 embodiment;
FIGS. 6A and 6B are views taken on line 6--6 of FIG. 5 and showing
the valve connections in the fill and fire settings, respectively,
of the actuating knob;
FIG. 7 is a cross-sectional view taken on line 7--7 of FIG. 1;
FIG. 8 is a cross-sectional view through a modified form of the
invention;
FIG. 9 is a view taken on line 9--9 of FIG. 8; and,
FIG. 10 is a pictorial view of the valve assembly of the FIGS. 8
and 9 embodiment.
Referring more particularly to the drawings wherein the showings
are for the purpose of illustrating preferred embodiments of the
invention only and not for the purpose of limiting same, FIG. 1
shows the preferred overall arrangement of an injector including a
controllable volume injection assembly 10, a medicament and
actuating fluid supply assembly 12, and an actuating and control
valve assembly 14 which serves to regulate flow between assemblies
10 and 12.
It should be appreciated that the assembly A is shown somewhat
larger than actual size; however, the specific size and/or
configuration of the assembly could vary substantially within the
scope of the invention. For this reason, the invention is not to be
assumed as limited to the specific details shown.
All of the assemblies 10, 12 and 14 are preferably carried in a
common housing or body forming member 16 which can be formed from
any suitable material such as aluminum, stainless steel, certain
plastics and ceramics. The controllable volume injection assembly
10 is carried within the forward end of the body 16 and includes a
cylindrical chamber 18 formed inwardly from the lower surface of
body 16. The chamber 18 is formed inwardly from the lower surface
of body 16 and, at its inlet end, has enlarged threaded bore
portion 20. Positioned within bore 20 is a threaded plug 22 having
an outwardly extending threaded sleeve 24. It will be noted that
the inner face of plug 22 is provided with a tapered bore 26 which
extends inwardly from the inner face in alignment with the axis of
chamber 18. Connected to the outwardly extending sleeve 24 is an
injection nozzle 28. The chamber and all passageways are formed
from material or lined with material to provide a non-wettable
surface.
Nozzle 28 can be formed in many different configurations and have
outlet orifices of different sizes depending, for example, upon the
particular type of injection to be given. In the subject
embodiment, the nozzle 28 merely comprises a machined body portion
provided with a tapered opening 30 which is aligned with the
opening 26 and terminating in an outlet orifice 32. Preferably, the
outlet orifice 32 is formed in a nylon bushing 34 which is
press-fitted in the nozzle and sealed with an "O-ring." This allows
a common nozzle body to have many different orifice sizes.
Positioned within the cylindrical chamber 18 is a movable wall
means in the form of a piston member 36 which divides the chamber
into a medicament chamber portion 38 and a pressurizing gas chamber
portion 40. It should be appreciated that instead of a piston, a
fixed diaphragm or the like could, in certain instances, equally
well be used. The piston 36 can be formed from any suitable
material but is shown as a plastic or polymeric material such as
polyethylene, polypropylene. As is apparent, the piston is mounted
for sealed, sliding movement within the cylindrical chamber 18. Its
upward limit of movement is adjustably controlled so as to allow
the volume of the medicament chamber 38 to be varied as desired. In
the embodiment under consideration, adjustment is controlled by a
threaded stud member 42. As shown, stud 42 is threaded in an
opening 44 formed inwardly from the upper surface of the body 16 in
alignment with the chamber 18. By rotating the stud, the upper
limit of travel of piston 36 can be varied to thereby vary the
quantity of medicament that can be held in chamber 38. A threaded
collar or sleeve 44 is positioned about the upper end of stud 42
and the sleeve and stud suitably scribed or marked so as to provide
a micrometer type adjustment and indication of the degree of
movement of the stud.
As can be appreciated, with medicament in chamber 38, the piston
will be moved upward into engagement with the lower end of stud 44.
Thereafter, high pressure fluid, preferably gas, can be supplied to
chamber portion 40 to drive the piston downwardly to cause the
medicament to be expelled at high velocity through orifice 32. The
gas pressure is supplied at a level such that the medicament
discharged from nozzle 32 has a velocity sufficient to penetrate
the patient's skin tissue or muscle to the depth desired. It should
be understood that the nozzle or orifice size as well as the number
of orifices can be varied depending upon the particular type of
injection being given and the particular desired end-effect.
Many different types of medicament and gas supply assemblies could
be provided; however, in the embodiment shown, a novel, multiple
dosage supply assembly 12 is used. The assembly 12 could take many
forms but, in the preferred embodiment, comprises a movable housing
which can be indexed to bring different gas cartridges and
medicament containers or ampules into proper position. The housing
comprises a rotatable cylinder 48 having a multiple number of
axially extending openings formed therein. The openings and their
relationship will be described more fully hereafter but, for
present purposes, it is sufficient to note that they are designed
to hold small sealed cartridges of high pressure gas and ampules of
medicament. The individual ampules are received within the openings
and can be connected through the valve assembly 14 with the
medicament chamber 38 and the gas chamber 40 by the valve assembly
14. FIG. 4 shows a typical cylindrical ampule or cartridge of the
type which is to be used in the unit.
Referring again to FIGS. 2 and 7, it will be seen that the cylinder
48 has two concentric rows of axially extending openings. An outer
row, preferably somewhat larger in diameter than the inner row, has
seven openings 50 of uniform diameter adapted to hold pressurizing
gas cartridges. The inner row of openings has a plurality of
openings, for example seven, each of a uniform first diameter
arranged to hold similar medicament ampules which are somewhat
larger or smaller than the gas pressure cartridges. Although the
openings could be of a uniform size for both gas and medication,
the arrangement shown is preferred since it prevents inadvertent
placing of a gas cartridge within a medicament opening.
The eighth hole in each row is arranged to allow cleaning of the
assembly. Opening 54 in the inner row can be utilized for holding a
containers or cartridge of cleaning fluid such as buffered
physiological salt solution with an added disinfectant or the like.
The outer large diameter opening 54 is used for a pressurizing gas
cartridge of somewhat larger diameter but lower pressure. The
opening 53 is of a larger diameter than the openings 52 so that the
cleaning fluid cannot be placed by mistake into a medicament
chamber. Further, the use of a larger diameter opening 54 prevents
use of a high pressure cartridge so that cleaning fluid cannot be
expelled at a velocity sufficient to produce an injection. Although
the described variation in chamber openings is preferred for
preventing inadvertent injection of cleaning fluid, other methods
could be used. For example, different chamber shapes, color coding,
etc.
Referring again to FIG. 1, the cylinder 48 is mounted for rotation
on a hollow, threaded stud or shaft 56 which is threaded into the
body 16. The body 16 has an axially extending circumferential
flange portion 58 which surrounds the cylinder 48 while allowing it
to be freely rotatable therein. The inner end the cylinder 48 is
provided with a cover plate member 60 which is releasably connected
to the cylinder by a threaded retainer sleeve 62. The cover plate
60 engages the inner ends of the cartridges and prevents them from
moving to the left in the cylinder during an indexing motion which
will subsequently be described. Note that the cover plate 60 has
openings slightly smaller than the corresponding openings 50, 52,
53 and 54.
In the subject embodiment, means are provided to allow the ampules
and cartridges to be punctured and connected in flow relationship
with the valve assembly 14. As best shown in FIG. 1, these means
comprise hollow needle-like members 62 and 64 carried,
respectively, in bores 66 and 68. Needle member 62 is mounted in a
threaded member 69 and connects from the valve assembly 14 to the
needle end portion 62. Similarly, the needle portion 64 is carried
in a threaded member 70. As shown, the inner ends of the cartridges
and ampules are punctured as they are moved toward the needles.
In the subject embodiment, the means for controlling rotation and
movement of the cylinder 40 comprises a retractable indexing
mechanism which includes an outer cup-shaped cover member 72 which
is connected to and moves with cylinder 48. Cover member 72
includes an end wall 73 and a sleeve or wall portion 74. The side
wall portion 74 closely surrounds the outer circumference of the
rearwardly extending sleeve 58 on body 16. The end wall is
releasably connected to an internal stud member 76 by screw 75.
Stud 76 is slidably received within the outer end of the shaft 56.
Note that the stud 76 has a flange portion 78 which is closely
received within the center of the shaft 56. A compression spring 80
is positioned between the flange 78 and the inwardly extending
flange 81 so as to maintain the stud continually biased to the left
to pull the cylinder 48 inwardly. Additionally, it should be noted
that a snap-ring 82 is positioned on the outer end of stud 76.
Accordingly, the screw 75 can be removed to remove the cup-shaped
member 74 and the cylinder for access to the outer ends of the
ampule and cartridge holding openings. The snap-ring prevents the
stud from sliding within the center of shaft 56.
Proper alignment of cylinder 48 to assure that the sets of gas and
medicament cartridges are brought into alignment with the needles
62, 64 is accomplished by a pin member 84 which is carried on the
inner face of end wall 73. Pin 84 is adapted to be received within
the openings 86 (see FIG. 7) formed in the end of the sleeve 58. It
should be noted that the openings 84 are aligned with the rows of
medicament and gas receiving openings of cylinder 48. To index the
cylinder 48 to bring a new set of cartridges into alignment with
the pins or needles 62, 64, it is only necessary to retract the
cup-shaped member 72 to the dotted line position of FIG. 1. At that
time, the needle 84 is free of the end of sleeve 48 and the
assembly can be rotated until the pin 84 is in alignment with the
next opening 84. The cylinder 48 and the cup-shaped end member 72
can then be pushed to the left causing the new cartridges to be
punctured by the needles 62 and 64.
Many different arrangements could be used for controlling the fluid
flow of the medicament and high pressure gas from the cylinder 48
to the injection assembly 10; however, the preferred valving
arrangement is comprised of a rotary slide valve member 90 which is
carried within a bore 92 formed intermediate the sections 10 and
12. The slide valve member 90 is cylindrical and includes a
central, somewhat large diameter section 94 and reduced diameters
end sections 96 and 98. Suitable passages which will be
subsequently described in detail are formed through the central
portion 90 to provide connection with the gas and medicament
passages. The lower reduced diameter end portion 98 of the valve
member is slidably and rotatably received within a plug member 100
threaded into an enlarged diameter bore 102 formed in the lower
surface of the body 16. A flange 104 is slidably received within
the bore 102 and a compression spring 106 is positioned between the
inner face of the threaded member 100 and the flange 104. Flange
104 engages the shoulder between sections 90 and 98 of the valve
member. Accordingly, the valve member is normally biased to the
upper position shown solid in FIG. 1.
The upper reduced diameter end 96 of valve member 90 is provided
with a knob or the like 108 which is releasably connected to
portion 96 in any convenient manner such as through the use of a
set screw 110. As can be appreciated, the valve 92 can be rotated
by knob 108 and, further, by pushing downward on knob 108, the
valve can be moved downwardly against the bias of spring 106. This
particular arrangement allows various selected passages between the
sections 10 and 12 to be connected in desired manners. It should be
noted that the lower end of valve member 92 is slotted as shown at
93 in FIGS. 1 and 5. A corresponding fin 95 is carried in plug 100
so that the valve member can be pushed down only when the fin and
slot are in alignment, which is in the fire position. Also,
positioned under actuating knob 110 is a spring biased detent
plunger 111 which engages recesses formed under the knob 110. As
the knob is rotated between various positions, the detent plunger
provides an indication of proper positioning of the knob.
FIGS. 3, 5, 6A and 6B best illustrate the arrangement of the
passages which permits control of the flow of gas and medicament to
the injection section 10. As shown, the valve assembly 14 connects
the needle 62 with passage 112 to permit medicament to be supplied
to the medicament chamber portion 38 of chamber 18. Similarly, the
valve controls the supply of pressurizing gas from needle 64 to
passage 114 and the connecting passages 116 leading from line 114
into the gas chamber portion 40 of chamber 18.
As best shown in FIG. 5, the slide valve member 92 has a first
cross passage 117 formed in its upper end. When the valve is
actuated downwardly, passage 117 connects the needle assembly 64
with passage 114. In its upper position, shown by solid lines in
FIG. 5, passage 114 is connected with an internal passage 118 which
leads to the lower end of the slide valve member 92. Referring to
FIG. 1, it will be seen that a corresponding passage 120 is formed
through the member 100. Thus, in the solid line position of FIGS. 1
and 5, the gas pressure chamber is connected with atmosphere so as
to relieve any internal pressures within the chamber.
The valve member 92 also includes a cross passage 122 which is
positioned at a 45.degree. angle relative to passage 117.
To understand the sequence of operations during filling and firing
of the injector, reference is again made to FIGS. 3, 5 and 6A and
6B. Assume that the knob 96 is turned so that the indicator arrow
124 is pointing toward the "off" position. At this time, the slide
valve is in its upper solid line position of FIGS. 1 and 5.
Accordingly, line 114 is directly connected to atmosphere through
line 118 and the cross-connection line 122 is positioned out of
alignment with the passage 112. In this way, no flow can take place
from the needles 62 and 64 to the gas or medicament chamber
portions when the injector is in the "off" position. However, when
the valve is rotated so that the indicator arrow 124 points to the
"fill" position, passage 122 is in alignment with passages 112 and
needle 62. Accordingly, medicament can flow from the medicament
capsule into the medicament chamber portion 38. Preferably, and in
accordance with one aspect of the invention, the medicament in the
capsule is under a slight pressure so as to cause it to be expelled
from the capsule to raise the piston 36 into engagement with the
lower end of stud 42 thereby filling the chamber. (It should be
recalled that by adjustment of the stud 42, the volume of chamber
38 can be varied.) With the medicament chamber properly filled, the
valve is then rotated 45.degree. further so that the arrow 124 is
pointed at the "fire" position. At this time, cross passage 117 is
aligned with passage 114 and needle 64; however, it is in the
raised solid position shown in FIGS. 1 and 5. Consequently, the gas
pressure passage is still in a closed position. When it is desired
to release the gas to produce an injection, it is only necessary to
push down on knob 108 to bring passage 117 into alignment with
needle assembly 64 and passage 114. Thus, as can be seen, one valve
assembly controls all filling and firing operations of the
unit.
When it is desired to clean the medicament chamber, it is only
necessary to index the cylinder 48 to bring the chambers 52 and 54
into alignment with the needles 62. Thereafter, the same fire and
fill operations can be carried out to produce a cleaning of the
assembly. Preferably, the gas pressure within the ampule positioned
in chamber 54 is substantially less than that required to produce
an injection. This eliminates the possibility that cleaning
solution could be injected accidentally. It should also be
appreciated that the outer circumference of the sleeve 74 and 58
can be suitably marked with indicia to indicate the presence of
cleaning cartridges in alignment with the needles 62, 64.
Although the particular rotary cylinder arrangement described is
preferred, it should be understood that other types of indexable
assemblies could be used, for example, slide clip assemblies,
multiple barrels or clips, and similar arrangements. Further,
although the unit is shown as having seven medicament holding
chambers, it should be understood that other numbers could be
provided. The number seven is preferred however, since it allows a
week's supply of medicament to be carried within the unit.
FIGS 8 and 9 illustrate a modified form of the invention which
utilizes a substantial different injector assembly and which can
use the same type of indexable supply chamber if desired; however,
it is shown with a simple supply section which holds only one
medicament ampule and one gas pressure ampule. In particular, the
embodiment of FIGS. 8 and 9 comprises a generally rectangular body
150 formed from any suitable material, either metal, plastic, or
ceramic. The body has a relatively large diameter, centrally
located cylindrical bore 152 which extends inwardly from the lower
face substantially through the body but leaving a small flange
portion 154. Positioned within the bore 152 is a slidable,
cylindrical housing member 156 which is closely and slidably
received within bore 152. Additionally, a key member (not shown)
prevents rotation of member 156 Member 156 is prevented from moving
out the lower end of the bore by a retainer ring 158 threaded in
the lower end of bore 152. The body member 156 is normally
maintained biased in engagement with retainer 158 by a relatively
light compression spring 160 positioned between shoulder 162 and
flange 154.
Formed axially within member 156 is an internal bore 164 which
constitutes the medicament and gas pressure chambers. The lower end
of bore 164 is provided with a small diameter outlet 166 which
connects with the nozzle outlet orifice 168. As shown, the nozzle
member 170 is releasably threaded to the end of body 156 so that it
can be changed as desired.
Positioned within the bore 164 and dividing it into a pressurized
gas chamber portion 172 and a medicament chamber portion 174 is a
piston 176. Piston 176 is formed from any suitable material so as
to provide a proper seal between the two chamber portions while
allowing relatively free movement of the piston vertically in the
chamber.
In this embodiment, adjustment of the medicament quantity is
controlled by a threaded sleeve member 178 carried in the upper end
of bore 164. By rotation of member 178, its lower end 180 is
shifted so as to vary the maximum vertical upward distance that the
piston 176 can move. This, of course, varies the space or size of
the medicament chamber 174. Adjustment of the member 178 is
indicated, for example, by suitable indicator marks formed on the
body 150 and the upper surface of member 178.
In the subject embodiment, means are provided for selectively
moving the piston 176 to its upper position so that filling of the
medicament chamber portion can take place. These means comprise a
vertically reciprocable shaft 182 having an enlarged lower end
portion 184. The shaft 182 is connected at its upper end with a
push button or actuating knob 184 having an outwardly extending
flange sealing surface 186. Note that the flange portion 186
engages under a machined flange or lip 188 formed internally of
member 178. This seals the pressure chamber. Additionally, a
biasing spring 190 acts against the under surface of push button
178 to maintain the shaft and push button normally biased to the
solid line position. At is lower end, the spring 190 engages a snap
ring 192 positioned in an internal groove in member 178.
To raise the piston 176 to its upper position, push button 184 is
pushed downwardly driving the enlarged diameter end portion 184
into a correspondingly shaped opening 194 formed in piston 176.
Thereafter, release of the push button allows the spring 190 to
push the shaft and push button back to the solid line position
shown. This pulls the piston 178 upwardly into engagement with the
end face 180. Additionally, portion 184 retracts from opening 194
and the piston stays in its raised position merely by friction
between the piston and the internal walls or bore 164. With the
piston in the raised position, medicament can be supplied to the
medicament chamber 174.
In the subject embodiment, the medicament ampules and gas
cartridges 198, 199 are carried in suitable bores formed inwardly
from the right hand end of body 154. Note that a cover plate 204 is
connected to the body with a screw 206. By removing screw 206,
cover plate 204 can be removed and the used cartridges removed and
new cartridges placed therein. Additionally, suitable needles for
puncturing the ends of the sealed cartridges are carried on the
inner ends of the bore in the manner shown in FIG. 8.
The medicament is supplied from medicament ampule 198 through the
valve assembly 200 to line 202 which connects through passage 166
with medicament chamber 174. Preferably, the medicament ampule is
under a slight internal pressure so that medicament is forcibly
actuated into the chamber 174. However, although the medicament
ampule is shown as having a different configuration than that used
in the FIG. 1 embodiment, it should be appreciated that the same
medicament ampules could be used, if desired.
The valve assembly 200 comprises a cylindrical valve member 210
closely received within a cylindrical bore 212 formed inwardly from
the upper surface of body 150. The valve member 210 is retained in
the bore while being free to rotate by a retainer plate member 214
which is positioned in a groove 216 which extends across the top
surface of body 150. A flange 218 is formed about valve member 210
and is held beneath the plate 214.
Valve member 210 is provided with transversely extending passages
which function to connect the gas and medicament supply passage
with the chambers. At the lower end of the valve member 210,
passage 218 is positioned so that when the valve member is rotated
to the "fill" position shown in FIG. 9, passage 218 connects from
the needle 220 to the passage 202. At this time, the upper
transverse passage 222 is out of alignment with the gas supply
needle 224 so that the apparatus cannot be inadvertently fired.
After the medicament chamber 174 has been filled, the valve member
210 can be rotated back to the "fire" position. Consequently,
transverse passage 222 is aligned with needle 224 and passage 226.
It is still not possible however, to supply high pressure gas to
the gas chamber 172. Note that the connecting passage 228 is formed
from the gas chamber 172 through the wall of member 156 as best
shown in FIG. 8. Although passage 228 is in vertical alignment with
passage 226, in the normal position of member 156 it is
substantially therebelow. Accordingly, engagement of member 256 and
the internal wall of bore 152 serves as a valve to prevent flow of
gas into the gas pressure chamber. When it is desired to inject the
medicament, it is only necessary to press the nozzle against the
patient's skin and move member 156 upwardly against the bias of
spring 160. When passage 228 is aligned with passage 226, high
pressure gas can flow into the chamber to product an injection.
Various modifications of the components of the described unit can,
of course, be made. For example, rather than use a rotary valve as
shown, various types of snap acting or slide valves could be used.
Further, although not shown, different types of O-ring seals and
the like could be utilized to provide sealing between the various
surfaces.
Cleaning of the subject embodiment could be accomplished in the
manner described with reference to the FIGS. 1 through 9
embodiments, i.e., a pressurized cleaning fluid ampule could be
placed in the chamber for the medicament ampule 198 and the unit
filled and fired. However, the subject embodiment provides an
arrangement whereby the passage 230 can be used to flush cleaning
fluid through the medicament chamber 174 as well as through the
medicament ampule and the needle 220. Note that a second needle 232
is connected into the medicament ampule 198. A flow passage 234
connects from needle 232 to the bore 212. Valve member 210 has a
transversely extending passage 236 which, when the valve is rotated
to the clean position, connects between lines 230 and 234. Also, a
laterally extending cross passage 238 is, when the device is in the
cleaning position, connected between lines 202 and needle 220.
Consequently, cleaning fluid can be flushed with a syringe through
line 230 and needle 232 back through needle 220 to chamber 174.
Many other modifications of the device can be made. For example,
the nozzles 28 and 170 can be color coded with the medicament and
gas pressure ampules for various types of injections. For example,
for intramuscular injections, a higher gas pressure may be used
together with a nozzle of a particular diameter. In such instances,
the proper nozzle can be made of the same color as the gas pressure
cartridge. These and similar modifications are within the scope of
the invention as set forth in the appended claims.
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