Note: Descriptions are shown in the official language in which they were submitted.
2~97~
W O 92~1022~ ~ . PCT/AU~1~00566
JET l 1QR QR ~S IN~C~LATION
BA~K~RQ~LND OF THE_LN.VENTION
The presen~ lnvention per~ains to needleless injectors and ~ore
particularly to a needleless ~e~ injector for mass lnoculation.
SUMMARY OF THE INVENl~LON
~t i5 ~n ob~ect of ~he present invention to provide ~ iet injector
which facilit~tes mass ad~inistration, by in~ection, of ~eterinary or
human ~edicat~on from a bulk supply.
Accordlngly, the ln~ention provides, in a first aspe~t, a
n~edleles5 Jet inje~t~r device ~or use with a supply of gas under
pressure and medlcament, th~ devlce comprist~g a body ha~tng a gas lnlet
for sai~ ~as and a medicament iniet ~o~ said medicament, a ~irst chambe~
communicatjng w~th said medicament inlet and havin~ an out1et, ~ jet
nozzle eommunicating wi~h said outlet so ~s to receive medtcament, under
pressur~, ~or ~njection, a second chamber communicatlng with said ~as
inle.~, a ~irst piston at least partly defining sald flrst cha~ber zn~
mova41e ~o vary the volume thereo~ so as to ~eliver a dose of medieament
und~r pressurQ ~o sa1d ou~l~k, a second piston ~t least partly de~tning
sald second ~h~mber and ~vable to ~ary the volume thereof, connection
means ~oupllng th~ first and second plstons so that movement of said
second plston causes movement of sai~ first piston, medicament flow
control means to operatively restrict flow of the medicamen~ ~rom the
medicament inlet to said ~rs~ chamber, and control me~ns to ~egulate the
flow o~ gas to said s~cond chamber to cause moYem~nt of sald second
pis~on ~nd therefor movement of said first pis~on.
In a preferred embodiment, the medication is carrled by a ~ckpac~
which suppll~s ~he ln~ector. The inj~c~or p~eferably au~omatically
r~l4ads a medication cylinder upon th~ releas~ of a trigg~r m2chanlsm at
the c~mpletlon of ~ch injection.
3~ It ts ~r~fPrr~d that tho do~ago bo roa~l ly ad justablo by me~n~ o~
piston st~ok~ ~djust2r.
One embo~ment of a jet injector accordin~ to the present ~nv~ntion
will now be moro fully describe~, ~y way ~f ex~mDle, with reference to
35 the draw1n~s~ of ~hi~h~
Floure 1 ~* A l~r-nes-s~tion~1 vi~w of ~n~ ~mbc~d~ ent Of A jet
in~ec~or d~cordtng to the present inventlon; ar~d
1 L610 nN 98bS19~ ~ 19 ~IOSn~`d~ OSn~dS 90 l1 ~661 ~In~ l
w 0 92~10~26 ~ 2 - 2 ~ 9 7 9 ~ 9
FigurQ Z is a perspeetiYe view of the injeetor o~ Flgure l and a
bac~pack used to carried ~e~icament and propellant.
DETAILED DESCRIPTION OF THE DRAhlIN~
As shown ln f1gure l, a nee~leless 3et injector lO0 eomprises a
noz~le l through which a high pressured je~ is discharged. Puring the
delivery stroke of a delivery piston 31 a check val~e 2 opens, allowlng
medicat~on to pass through the nozzle l. The check valve 2 closes on the
intake stroke o~ the plston 3 to prevent air from being drawn lnto the
interchangeable medieatlon cylinder 22. As the piston 3 re~iprocates,
medicat~on is al~ernately drawn into the ~ylin~er 22 ~nd ~lscharged
thro4gh the nozzle l.
A me~icatton transfer tube ~ enables medication to be ~ansferred
from a medl~ation receiver 6 to the med~cation cylinder 22. A check
valve 5 clo~es on the dQlivery s~roke o~ the piston 3 preYQnting
medication from passing back into ~he re~eiver 6. The eheck valve 5
opens on the ~ntake s~ro~e of ~he piston to allow medication to flow ~rom
the recetv0r 6 to the cYlinder 22. The medleat~on receiver 6 is a
~hamb~r ~thln the body o~ the injeCtor which receives and holds
medlcation fro~ an external soUrce such as a baekpack.
2~ To ensu~e that the rear port10n o~ the cyllnd~r ~ln ~hlch the
piston rod 8 resl~es~ is open ~o atmospher~c pressure during b~h intaka
and dell~ery stro~e~, a cylinder ven~ 7 ts provided throu~h the rear of
the mQdlcatlon cylin~er.
The piston rod ~ connec~s the delivery piston 3 to a ~2
pis~on 9. When a pressurlzed ~as such as C02 i~ released from ~he
C2 receiv~ng chamber 13 it passes through ~ ~2 release valve 14 (if
open) and tnto a C0z chamber 24. ~ collar st~p lO i5 provided ~n the
ch~mber 24 ~or limiting and ad~sting the retu~n stop position of the
p~ston 9. A ~orm and rack ~echanism ll respond~ to rotation o~ the
30 st~oke adiust~r 12, movlng the stop lO ~orward and backward in a linea~
~shion thereby altering the stroke o~ ~he plstQn 9.
The C02 release v~1ve 14 is opene~ by aetuation o~ ~he tr~er
and l~ver mechanism 20 actlng through ~he release valve actuator 15,
Opening the C02 rel~ase valYe 14 allows pressurized g~s to travel from
~5 ~hQ recelvlng ~hamber 13, lnt~ t~e delivery cha~ber 24 and hence lnto the
working portion of th~ cylinder 23 ~or the p~rpose or displacing the
plston 9.
g 1 1.610 N ~ I.q ~ n~ Nl~r~ n.ll ~fifi~ un~ l.
~o 92/~02~fi _ 3 _ 2 ~ ~ 7 9 ~ 9 PcrfA~9l/005~
A r~lease \lalve ac~ua~4r 15 is provide~ which~ upon upward
deflection of the trig~er and le~er ~echanism 20, opens the C02 release
valve 14 an~ closes the C02 cylinder vent Yalve 16. ~ith the trigger
an~ lever mechanism Z0 Stlll held in the upward deflected posltionl the
rele~se valve actuator lS allows the release valve 14 to ~lose, stopplng
the ~low o~ pressurized g~s lnto the delive~y ¢hamber 24 at the
completlon of ~he delivery st~oke.
The cyl~nde~ vent valve 16 ap~ns upon the rel~ase of the ~r~gger
and l?ver ~echanism ~0 and allows the cylinder Z3 ~o be vented to the
10 atmosphere via the cy1inder port 17, lever por~ 18 ~nd handle vent 19.
At the completion o~ the delivery stroke, a t~nsfer valve 21 opens
and allows pressvrized gas to fill the return chambe~ 2~. Upon release
o~ the tr~gger end lever mechanism 20 the cylinder ~ent ~ e ~6 opens
and the cyllnder 23 is vented ~o atmosphere ~hlch ln turn allows the
1~ pressu~lzed g~s in ~he return chamber 25 to drive the piston 9 back to
the collar stoP 10. With th~ return ~ravel o~ the plston 9, the piston 3
~raws medication into the ~edicatian cyllnder 22.
As sho~n in ~ig~re 2, a trlgger operated jet injec hr ne~teless
syrtn~e 100 according to the teach~ngs o~ the present inventi~n may be
~se~ ln con~U~ct~on with a ba~kp~ck harness 101. The harness 101 m~y be
used to support a medi~amen~ cytlnder 102 and a liquid carbon dioxide
cy71nder 103. The Con~ents of the medicament and C02 cylin~ers ~re
discharge~ through a manl~old 104 and through separate hoses 1~, 105 to
the respect~ve intake ports of the injector 100.
Z5 The backpack harness may consist of a ri~id mount~n~ frame which
includes wa~st and shoulder straps whieh can be ad~usted to the wearer~s
needs. The C02 and medtcament ~anifold(s~ may either be attached to
the harness or separately attached to Qach of the cyllnders.
The pressur ked gas cylinder, preferably a carbondlo~lde cyl~nder,
will 4e ~ high pressure c~linder containing approximately Z.5 kilo~rams
of llquid car~on dioxide which is used as ~he pressu~e medium for
~tuatin~ th~ plston 9.
The ~edicament ~yllnder may be an unpr~ssurized vessel of 1ight
hei~h~ material to contain ~he particular medicament use~ in a partic~lar
35 lnoculation program~ Like ~he pressurized gas cylinder lt ls readily
~eplacable and refillable.
1. ~ n ON q~C 1 ~7 7 l a Mf\Cn~TIT~ :~ AlrlCn~TrTC I n ' l T ~ n ,~ I
WO ~/10226 4 P~T~AII~1/005~6
- 2~7c~
Both the medicament cylinder 2~ and no~zle 1 of the iniecror 100
are replacable. The ~ylinder may be tailored to suit the cor~eCt ~age
o~ a particular medtcament. The noz~le contains a very fine bore whleh,
on release o~ the pts~on 4nder the gas p~essure, wi~l create a high
p~essure, high veloçlty ~et. The nat~re o~ the high veloci~y iet throush
the fine bore creates ~ear within the bore and after a perl~d of time,
thls wear ~ e~uce the efficiency of p~netration o~ the medicamen~.
The nozzle is ~he~e~ore readily replacable in the fiel~ at the first slgn
of r~du~ed ef~iciency which will be not~iç~ble by wetting of the skin
surface.
The ~njector portion 100 may b~ provlded in two or more sizes
utllising the same operating principles. A larger robust unit ts
par~te~larly su~ted to mass inoculation o~ sheepl cattl2, pi~s an~ other
animals, A s~aller ~nit is more suitable for the mass inoculation o~
~hlldren and adults.
A ~a~or benefit of this invention ls the fully auto~atlc reloading
~nd recha~ging for rapi~ multlpte injections. The unlt ls ~u11y
ad~ustable ln ~oth dosage and charge for diffQ~nce thickness s~lns and
~lfferent stzes o~ antmals. ~ecause it is a needleless syringe, tt
completely elimtnates ~he problem of cross contam~natlon or infectton
~hich exlsts w~h mass inoculation ~ith multiple u~e n~edles,
~ hlle the present ln~ention has been des~ribe~ w~h re~erenee to
parttc~lar mechantc~t ~o~ponents and detatls o~ ¢onstruction, these
should ~e understoo~ as having been provided by ~ay of example an~ not as
limt~atjon to the scope of the invention.
8 d l610 N 98~ ( % 1~ Nr)~n~ Nrl~n~i~ 2h l.~ 1 un~ 1
