Title of Invention

REUSABLE MULTI CHAMBER AUTOINJECTOR DEVICE TO IN JECT TWO DRUGS BY A SINGLE INJECTION

Abstract

ABSTRACT The reusable multi-chamber Auto-Injector is spring operated and pemiits injection of two drugs one after the other sequentially at different depths of the muscle. The drug cartridge is sealed on one end with a stopper. It has two drug chambers; the first chamber between the stopper and septum contains 2 PAM Chloride and hub with cannula. The second chamber is between the septum and the plunger and is filled with atropine sulfate. The cartridge has two lateral bypass grooves in the first drug chamber. The grooves are made in such a way that the drug in the second chamber flows into the first chamber only when the drug in the first chamber is completely injected. The second drug is injected subsequently when the cannula is fully extended. The autoinjector is reusable and can be modified for using it for injection of single drug. To. The Controller of Patents, Chennai.

Full Text

TITLE Reusable Multi-chamber Auto-injector to inject two drugs by a single injection. FIELD OF INVENTION The present invention relates to auto-injectors and drug storing cartridge assemblies. More particularly, the present invention relates to an auto-injector and multi-chamber cartridge assembly having structure allowing for automatic injection of the medicament through single injection into the body at different depths without combining both the drugs and a method for making the multi-chamber cartridge assembly. BACKGROUND OF THE INVENTION Auto-injectors are specifically intended for use in emergencies and disasters to save time. The administration of drugs by autoinjector is easy and time saving. They are handy for medical and paramedical workers. The injectors are prefilled with life saving drugs. One of the advantages is that the needle is not visible. The fear of prick, stress and trauma are eliminated. Earlier devices were made to inject a single drug at a time. At times of organophosphate poisoning there is a requirement of administering two life- saving antidotes at the same time. Two separate injections would be time consuming. A search was on for an autoinjector ttiat can inject two drugs simultaneously one after another through a single needle. In addition it should be ensured that the dmgs are stored separately in stored condition to prevent chemical interaction between them. It is also expected that the drugs be injected one after another without mixing of drugs while being injected and the drugs should be delivered in separate pockets in the muscle tissue. The present invention of reusable multlchamber autoinjector reported satisfies all the conditions and it is very simple to operate. RELATED PRIOR ART Efforts were on for the past two decades to develop suitable autolnjector for self-administration of life saving drugs. Many inventors have reported single chamber autoinjectors. Now the emphasis has shifted to autolnjector that is capable of injecting two drugs through a single needle. One invention was reported where in two drugs kept separated in a storage position and injects both drugs one after another when activated. Another invention has reported a combination of a liquid drug and a powder with a filter device. The aim of ail the devises is that they can be used at times of emergencies and disasters. These devises are useful for administering antidotes for organophosphate poisonings and in emergencies. The experience of Methyl Isocyanate disaster in India is fresh in the memory of people. OBJECTIVES OF THE INVENTION The objective of the invention is to provide an Improved reu^ble auto-injector capable of holding two drugs separately while in storage condition and inject the drugs sequentially one after the other preventing them from mixing, while being injected. The autoinjector has to inject one daig when the cannula is moving forward in the muscle and inject the second drug when the cannula is fully extended in the muscle. Another objective is to invent a reusable autoinjector, wliich can be used by simply replacing the used cartridge with a new cartridge. Another objective is to replace the glass cartridge with a suitable plastic material to make it sturdy and fit for field conditions. Another objective is to replace the conventional needle with a plastic hub fitted with a cannula. The hub should keep the cannula straight. Another objective is to provide a safety clip as a locking device to prevent accidental firing of the autoinjector. Another objective is to provide a suitable safety cap to prevent contamination to the drug cartridge and keep the autoinjector in sterile condition. SUMMARY OF THE INVENTION The Multi-chamber Auto-Injector is a very simple device that permits injection of two drugs sequentially one after another through a single cannula. It is for use in emergencies and disasters. It is ideal for medical and paramedical workers administering antidotes to Organo phosphate poisoning. Earlier practice was to inject each drug separately, which is time consuming. The multi-chamber Auto¬injector permits injection of the two drugs one after the other at different depths in the muscle. The drug cartridge is closed on one end with a stopper. It has two drug chambers; the first chamber contains 2PAM Chloride and a hub with cannula. The first and the second chambers are separated by a septum. The second chamber is between the septum and the plunger and is filled with atropine sulfate. The cartridge has two lateral bypass grooves in the first drug chamber close to the stopper. The grooves are made in such a vray that the drug in the second chamber flows into the first chamber only when the drug in the first chamber is completely injected. The auto-injector is simple to operate and is spring operated. Rotating the safety clip clockwise to unlock the trigger and pressing the trigger activates the Auto¬injector. The trigger releases the spring that is in a compressed position. The force of the spring pushes forward the plunger, drug in the second chamber, septum, drug in the first chamber and the hub with cannula. The sharpened edge of the cannula pierces the stopper, the skin at the site of injection, the muscle and injects t50th drugs one after another at different depths. The safety clip prevents any accidental fifing of the trigger. A safety cap provided In front of the auto-injector Is to keep the cartridge fronfi external contamination while in storage condition. The safety cap has to be pulled out manually before the injection is taken. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 illustrates the longitudinal section of the auto-injector showing the placements of the components after loading the cartridge filled with drug. Fig. 2 illustrates the longitudinal section of the auto-injector showing the position of the components after the first drug is injected. Fig. 3 illustrates the longitudinal section of the auto-injector showing the p Fig. 4 illustrates the blowup of the components of the auto-injector in perspective angle. Fig. 5 illustrates the hub with cannula with four lateral grooves on the sides leading to the inlet of the hub on the base. Fig. 6 illustrates the cartridge showing different views. Fig. 7 illustrates the vertical section of the cartridge showng the component assemblies when fully loaded with both the drugs. Fig. 8 illustrates the vertical section of the cartridge showing 8ie position of tfie components when the first drug is delivered. Fig. 9 illustrates the vertical section of the cartridge showing the position of the components when the second drug is delivered. DESCRIPTION OF THE INVENTION In the drawings the numerals depicted, as 1 is the cap. 2 is the spring which gives stored energy for the auto-injector to push the plunger rod fon/vard. 3 is the safety clip which protects the device from misfiring. 4 is the plunger rod which holds the spring in compressed position and held in that position by the trigger. 5 is the spring ban-el in which the spring and the plunger rod are placed. 6 is the trigger when pressed releases the compressed spring into action. 7 is the cartridge barrel in which the cartridge is housed. 8 is the cartridge which holds the two drugs separated by the septum. 9 is the plunger, 10 is the septum which separates the two drugs in stored condition. 11 is the hub with cannula. 12 is the safety cap of the device. 13 is the cartridge cap. 14 is the stopper. 15 is the lateral bypass groove, 16 is the groove on the hub, 17 is the cannula, 18 is the hub front, 19 is the hub lateral groove, 20 is the stopper groove, 21 is the second drug chamber, 22 is the first drug chamber. DESCRIPTION OF PREFERRED EMBODIMENTS The Reusable Auto-injector is designed for self-administration and rapid delivery of drugs. The Auto-injector has an outer body having a (7) cartridge barrel in the front and a (5) spring barrel in the rear. The cartridge barrel is of uniform diameter having a thread at the back to be screwed to the (5) spring barrel. The cartridge ban-el has an opening in the front to permit the needle to eject. A (11) hub with cannula is placed in (22) first drug chamber of the cartridge. Both drug chambers (22) and (21) are separated by (10) rubber septum. The second drug chamber is between the (10) septum and (9) plunger. The (2) compressed spring and (4) plunger rod are housed in the (5) spring barrel. The spring barrel has a (1) cap to keep the plunger rod in position. The (6) trigger on the spring barrel holds the plunger rod in compressed position. Release of the frigger causes a progressive movement of the plunger rod, plunger, second drug, septum, and hub with cannula. The force on the sharpened end of the cannula punctures the (14) stopper, the skin at the delivery site, muscle and delivers both the dnjgs one after another. The (15) lateral by-pass groves in the cartridge permit the drug in the second chamber to flow Into the first chamber after the first drug is injected. The forward movement of the plunger pushes out the second drug after the first drug is completely injected. The groove on the hub (19), and (16) pemiitthe drug to flow back to hub base and inject out through the inlet of cannula. The forward movement of the cannula permits the doigs to be injected at two different depths in the muscle. DESCRIPTION OF WORKING OF THE DEVICE The drawings illustrate the working of the device, which has (2) spring in a compressed state and is held by the tip of the trigger (6) to prevent accidental firing, In addition a (3) safety clip is provided to keep the trigger in locked position. When the auto-injector is to be operated the (3) safety clip is moved clock wise till the tip touches the trigger bridge. The pre-filled cartridge is placed in the (8) cartridge barrel in the ft'ont and screwed to the (5) spring barrel. The (4) plunger rod keeps the spring in compressed position and is held by the by tiie trigger. When the trigger is released the spring force pushes plunger rod forward through an opening in the (5) spring barrel into the cartridge in the cartridge ban-el. The plunger rod pushes tine (9) plunger forward, which in turn pushes the drug, in the second chamber, (10) septum, (11) and hub with cannula. M the cannula moves forward it punctures (14) the stopper, the skin at injection site and the muscle till it is fully extended. In tiie process it delivers both the dnjgs a different depths. The drug cartridge (8) is housed in the cartridge barrel (7) of the autoinjector. The cartridge has two drug chambers (22) and (21). The drug channbers are separated by (10) septum in stored condition. In the first chamber (22) a hub with cannula is housed in addition to the drug. The (8) cartridge has almost uniform cross section throughout and is open on both sides. It has a stopper (14) in the front to seal the opening and kept tight in position by an aluminum cap (1). The cartridge has two chambers. A drug and a (17) hub fitted with a cannula are placed in the (22) first chamber. It is separated from the second chamber (21) with a septum (10). The second chamber (21) contains the second drug and is closed with a plunger (9). The hub is specially designed in that it holds the (17) cannula and serves to keep the cannula in a straight position. The hub has four (16) longitudinal grooves, two on both sides, one in the front and one in the back. All the grooves converge on the top of the base of the cannula. The grooves help free flow of the drugs as the plunger (9) pushes the cannula forward. It has a unique feature having two longitudinal grooves In the wall of the cartridge. As the plunger (9) pushes the drugs in a fonvard motion, the grooves facilitate the drug in the second chamber (21) to bypass the septum (10) and move on to the hub in the first chamber (22) and get injected out We claim, 1. A reusable multi chamber Autoinjector Intended for auto penetration mechanism comprising a front cartridge barrel to house the multi chamber drug cartridge connected to the spring barrel in the rear by a thread wherein the said spring barrel in the rear, in which the spring mechanism consisting of a compressed spring and plunger rod is placed and multi chambered cartridge Is divided into two chambers by stopper, septum and plunger. 2. The reusable multi chamber Autoinjector according to claim 1, wherein the trigger Is provided which operates the spring mechanism. 3. The reusable multi chamber Autoinjector according to claim 1, wherein two bypass grooves are provided in the wall of the cari:ridge close to the front end of the cartridge to permit the drug in the second chamber to flow into the first chamber only when the drug in the first chamber is injected. 4. The reusable multi chamber Autoinjector according to claim 1, wherein the length of the bypass grooves is very critical to permit the flow of the drug in second chamber to the first chamber only after the first drug is injected. 5. The reusable multi chamber Autoinjector according to claim 1, wherein the hub with cannula is positioned in the first chamber along with the drug. 6. The reusable multi chamber Autoinjector according to claim 1, wherein the tapered front of the cannula is touching the stopper in front and the proximal end is fused into the hub, the inlet opening on the base of the hub. 7. The reusable multi chamber Autoinjector according to claim 1, wherein the hub has a round front and has four lateral grooves on the sides converging on to the base of the hub leading to the inlet of the cannula. 8. The reusable multi chamber Autoinjector according to claim 1, wherein the cannula is fused to the hub which keeps the cannula almost parallel to the axis of the cartridge resulting in parallel penetration and injection movement. 9. The reusable multi chamber Autoinjector according to claim 1, wherein the thickness of the septum separating the drug chambers synchronizes the flow of the drug from the second chamber only after the drug in the first chamber is delivered. 10.The reusable multi chamber Autoinjector according to claim 1, wherein the two drugs are stored separately till the time of injection and when the trigger releases the spring mechanism, the first drug is delivered as the cannula moves forward in the muscle and the second drug is injected when the cannula is fully extended resulting the two drugs are in two pockets of the muscle. 11.The reusable multi chamber Autoinjector according to claim 1, wherein it has a safety clip that prevents accidental firing of he trigger when it is in a locked position.

Documents:

0793-che-2003 abstract duplicate.pdf

0793-che-2003 abstract.pdf

0793-che-2003 claims duplicate.pdf

0793-che-2003 claims.pdf

0793-che-2003 correspondence others.pdf

0793-che-2003 correspondence po.pdf

0793-che-2003 description (complete) duplicate.pdf

0793-che-2003 description (complete).pdf

0793-che-2003 drawings duplicate.pdf

0793-che-2003 drawings.pdf

0793-che-2003 form-1.pdf

0793-che-2003 form-19.pdf

0793-che-2003 form-26.pdf