Needle-free injection systems provide an alternative to standard fluid delivery systems, which typically uses a needle adapted to penetrate the outer surface of an injection site. Typically, needle-free injection systems are designed to eject the fluid from a fluid chamber with sufficient pressure to allow the fluid to penetrate the target to the desired degree. For example, common applications for needle-free injection systems include delivering intradermal, subcutaneous and intramuscular injections into or through a recipient's skin. For each of these applications, the fluid must be ejected from the system with sufficient pressure to allow the fluid to penetrate the tough exterior dermal layers of the recipient's skin.
When using the same device to deliver inoculations, immunizations or the like, to different individuals, preventing cross-contamination between injection recipients and prevention of contamination of the filling source must be a priority. Thus, it is desirable to provide a device that allows a user to move with reasonable speed from one injection recipient to another while maintaining adequate protections against cross-contamination. In addition, it will often be desirable to obtain the above advantages while also keeping waste to a minimum (e.g., by avoiding unnecessary disposal of portions of the injection system).
It is also desirable in many applications that an injector be relatively small, hand-held, and ergonomically comfortable so that it can be easily handled by the health care provider. When a spring loaded injector is being used, it is also desirable that the injector spring be easily compressed. These and other advantages of the preferred embodiments will be apparent as this description continues.
A needle-free injector is provided for injecting fluid from an injection cartridge that has a longitudinal axis, an injection orifice at a distal end and a displaceable plunger. The injector also includes an injector body having a longitudinal axis and a side opening to receive the cartridge from a position laterally offset from the injector body longitudinal axis. A closure mechanism is included for closing the side opening of the injector body after the cartridge is in position in the injector body with the longitudinal axes of the cartridge and the injector body coincident in order to lock the cartridge in place in the injector body.
Another aspect of the invention is a method for loading an injection cartridge into a needle-free injector, including the following steps: selecting an injection cartridge that has a longitudinal axis; selecting an injector body that has a longitudinal axis, a side opening and a closure mechanism for selectively closing the side opening; opening the closure mechanism of the injector body; moving the injector cartridge laterally from a position that is laterally offset from the longitudinal axis of the injector body through the side opening of the injector body into position in the injector body with the longitudinal axes of the injector body and the cartridge in alignment; and closing the side opening of the injector body to lock the cartridge in place in the injector body.
The invention alternatively provides a spring-loaded needle-free injector having an injector body, a main spring, and a winder that is rotatable in either the first direction or a second direction, and which can compress the main spring by rotating in the first direction. Also included is a ratchet mechanism in the form of a first and a second toothed member with at least one of the members being spring biased toward the other member, the ratchet mechanism being interconnected with the winder so that winding the winder in the first direction causes both toothed members to rotate, but winding the winder in the second direction causes rotation of only the first toothed member.
Yet another aspect of the invention is a method for compressing the spring of a spring-loaded needle-free injector which includes the steps of selecting an injector body having a main spring, a winder that is rotatable in either a first direction or a second direction and which compresses the main spring by rotating in the first direction, and a ratchet mechanism having rotatable first and second members with sloped teeth. At least one of the members is spring biased toward the other member. The ratchet mechanism is interconnected with the winder so that winding the winder in the first direction causes both toothed members to rotate but winding the winder in the second direction causes rotation of only the first toothed member. The winder is wound in the first direction, causing both of the members to rotate to compress the main spring, and then is wound in the second direction, causing only one of the members to rotate. The winder is then wound again in the first direction, causing both of the members to rotate to further compress the main spring.
Another aspect of the invention is a spring-loaded needle-free injector having a main body with distal and proximal ends and a longitudinal axis. An injection cartridge is provided that is mounted to the distal end of the main body, the cartridge having a fluid chamber defined therein and an injection orifice at the distal end. A trigger sleeve is slidably mounted to the main body, and a trigger lock that prevents the trigger from sliding with respect to the main body when locked is also provided. A firing mechanism that is actuated by unlocking the trigger lock and then sliding the trigger sleeve toward the distal end of the main body is also provided to fire the injector.
Yet another aspect of the invention is a method of injecting fluid from a needle-free injector that includes the following steps: selecting an injector having a main body with distal and proximal ends; slidably mounting a trigger sleeve to the main body, the trigger sleeve having the capability of actuating a firing mechanism when slid along the main body in a distal direction, the trigger sleeve having a trigger lock that can be locked and unlocked and which prevents the trigger sleeve from sliding with respect to the main body when the trigger lock is locked; mounting an injection cartridge adjacent the distal end of the main body, the cartridge including a fluid chamber defined therein and an injection orifice at the distal end thereof; and unlocking the trigger lock and sliding the trigger sleeve toward the distal end of the main body to fire the injector and cause the fluid to be ejected out of the fluid chamber and through the injection orifice.
The invention could also provide a needle free injector which includes an injection cartridge with a plunger and an injection orifice, an injector body, a system for providing injection power, a ram disposed in the injector body for transferring injection power from the system to the plunger, and a frangible member mounting the ram to the plunger such that the ram and plunger can be retracted under one amount of force to fill the cartridge with fluid, and such that when the ram and plunger are driven forward under another amount of force that is greater than the one amount of force, the ram breaks the frangible member but still allows the ram and plunger to drive fluid from the cartridge through the injection orifice. Therefore, in the event someone attempts to retract the ram and plunger to re-fill the cartridge, the ram will retract but the plunger will not because the frangible member has been broken.
A method for preventing the re-loading of a cartridge is also provided that includes the steps of selecting an injection cartridge having a plunger and an injection orifice, and selecting an injector body in which the cartridge can be removably mounted and having a system for providing injection power, a ram for transferring injection power from the system to the plunger, and a frangible member mounting the ram to the plunger such that the ram and plunger can be retracted under one amount of force to fill the cartridge with fluid, and when the ram and plunger are driven forward under another amount of force that is greater than the one amount of force, the ram breaks the frangible member but still allows the ram and plunger to drive fluid from the cartridge through the injection orifice. Therefore in the event someone attempts to retract the ram and plunger to re-fill the cartridge, the ram will retract but the plunger will not because the frangible member has been broken.
Yet another aspect of the invention provides a spring-loaded needle free injector for injecting fluid from an injection cartridge that has an injection orifice and a displaceable plunger. Included is an injector body, a main spring for providing injection power for the injector, a ram disposed in the injector body for transferring power from the main spring to the plunger, and a cartridge loading mechanism that retracts the ram for alternatively loading injection fluid into the injection cartridge or for facilitating the loading of a pre-filled injection cartridge.
A needle-free injector for injecting fluid from an injection cartridge that has a longitudinal axis, an injection orifice at a distal end and a displaceable plunger may also be provided in accordance with the invention. The injector typically includes an injector body having a longitudinal axis and a side opening to receive the cartridge from a position laterally offset from the injector body longitudinal axis. A closure mechanism is also included for closing the side opening of the injector body after the cartridge is in position in the injector body to lock the cartridge in the injector body. A ram is disposed in the injector body for transferring power from the system to the plunger, the ram being aligned with the longitudinal axis of the cartridge when the cartridge is in the injector body. A cartridge loading mechanism is normally also included that retracts the ram for alternatively loading injection fluid into the injection cartridge or for facilitating the loading of a pre-filled injection cartridge.
A spring-loaded needle-free injection system is further provided that includes a nozzle having a fluid chamber therein for containing injectable fluid and an injection orifice fluidly coupled with the fluid chamber. Also included is a main spring configured to be compressed during arming of the injection device, the spring-powered injection device being configured to forcibly eject fluid from the fluid chamber out through the injection orifice during decompression of the spring. This system typically also includes a filling adapter that is frangibly attached to the nozzle such that the filling adapter cannot be reattached to the nozzle after being broken away from the nozzle. Thus, the system is configured to prevent delivery of an injection from the injection orifice into an injection site until the filling adapter is broken away from the nozzle.
Before describing the operation of the depicted system, the various parts and their relationship to one another will first be described. A first embodiment of the injector system is depicted at 10 in
Beginning at the proximal end of injector 10, a dosage knob 24 is included. Dosage knob 24 includes fine, left-handed threads 26 which engage complementing fine threads 28 in a dosage drum 30. A dosage spring 32 is positioned within dosage knob 24 and dosage drum 30 and extends between the proximal end of the dosage knob and a dosage spring seat 34. Positioned within dosage spring 32 is a slide bushing extension 36 and a slide bushing extension seat 38. Slide bushing extension 36 and slide bushing seat 38 mount to and extend the length of a slide bushing 88, which will be described in more detail below.
Positioned around dosage spring 32 within the proximal end of injector 10 is an enlarged ratchet spring 40 which is designed to bias a second ratchet ring 42 toward a first ratchet ring 44. The first and second ratchet rings each include a plurality of teeth 45 and 43, respectively (see
A pair of small winder pins 46 are positioned within second ratchet ring slots 47 and winder slots 48 so that when the two ratchet rings are positioned within winder 16, relative rotation is not permitted between the second ratchet ring and the winder.
As seen best in
A pair of so-called clam shell halves 70 are mounted between dosage drum 30 and trigger sleeve 14 to prevent axial displacement between these two components, but permit relative rotation therebetween. Clam shell halves 70 are held together by a pair of clam shell screws 72. Clam shell halves 70 are engaged with trigger sleeve 14 by a pair of clam shell pins 74. The only engagement between clam shell halves 70 and dosage drum 30 is the engagement of a proximal leg 71 of the substantially U-shaped clam shell halves. That is, proximal leg 71 engages a complementing slot 73 in dosage drum 30. Thus, again, the dosage drum, winder and associated parts are held in engagement with the trigger sleeve, but relative rotation is permitted between them so that the winder can be rotated to compress a main spring 102, as will be understood as this description continues.
Continuing in a distal direction, a pair of trigger locks 76 are pivotally mounted to trigger sleeve 14 by trigger lock pivot points 78. Trigger locks 76 each include radially-extending trigger lock legs 80 that engage a ledge or notch 82 in main body 12. Each of the trigger locks 76 includes a trigger lock spring 84 that pushes the distal end of the trigger locks outwardly, thereby causing trigger lock legs 80 to engage notch 82 until the trigger locks are depressed against the outward bias of the trigger lock springs. In most applications only a single trigger lock will be included even though two such trigger locks are included in the depicted embodiment.
A trigger sleeve window 86 is provided in the side of trigger sleeve 14 so that a visual indicator can be provided to ensure the proper positioning of the components prior to firing. Window 86 can also be used to provide a read-out of the dosage that is being injected.
Referring again to the exploded view of
A trigger spring 90 can be seen to the positioned within slide bushing 88. Trigger spring 90 is seated in a trigger spring seat 92 which in turn is positioned within a firing sleeve 94. Four hardened steel balls 96 are initially positioned within four ball seats 98 in firing sleeve 94 for purposes that will become apparent as this description continues.
An upper spring seat 100 provides a proximal seat for main spring 102, which provides injection power for injector 10. A main spring seat 104 provides a distal seat for main spring 102. A substantially square washer 106 is shown to be positioned between main spring seat 104 and a ram 108. As shown, main spring seat 104 includes a central opening through which ram 108 extends. A ram bolt 110 extends out of the proximal end of ram 108 to provide a hardened surface for the proximal end of ram 108. Ram 108 includes a ram seat 112 and, at its distal end, a head 114 which is defined by a notch in the ram. The configuration of head 114 is designed to facilitate engagement of cartridge 20.
At the distal end of injector 10 is a cartridge lock 22, which is mounted to main body 12 by a cartridge holder 118. Specifically, external threads 120 in cartridge holder 118 engage with complementing internal threads 122 in main body 12 in order to properly engage the cartridge holder to the main body. A detent pin 128 and a small spring are provided to cause cartridge lock 22 to click into its locked position.
Cartridge 20 can be seen to include a plunger 130 positioned within a chamber 132 in a nozzle 140. The distal end of nozzle 140 includes an injection orifice 142. Plunger 130 includes a substantially U-shaped proximal end 136, which is designed to engage head 114 in the distal end of ram 108. This provides a solid mount that will convey forces conveyed between the ram and the plunger and yet permits easy engagement and disengagement.
Cartridge lock 22 includes a cartridge lock opening 138 (
Nozzle 140 may be loaded with injection fluid by the system described in my application Ser. No. 10/976,342, or any conventional system. Once nozzle 140 is loaded, the nozzle and its injection orifice 142 may be placed against the patient for injection.
While the depicted embodiment is a spring-loaded embodiment, it should be understood that it is also possible to use a gas-powered injector (not shown) in connection with the depicted described system for loading a cartridge from the side. Gas-powered systems are included in U.S. Pat. Nos. 6,096,002, 6,607,510, 6,645,170, and 6,689,093, which are incorporated herein by reference.
As winder 16 is rotated in the clockwise direction, the winder carries second ratchet ring 42. Ratchet spring 40 holds teeth 43 of second ratchet ring 42 against teeth 45 of first ratchet ring 44. This causes first ratchet ring 44 to rotate and along with it so rotates dosage drum 30, torque nut 60 and dosage screw 62. When winder 16 is ratcheted back in a counter clockwise direction, the teeth 45 and 43 of first and second ratchet rings 44 and 42, respectively, slip across each other without causing a reverse rotation of first ratchet ring 44, the dosage drum 30, torque nut 60 or dosage screw 62. As a result of this repeated back and forth rotation of winder 16, dosage screw 62 is turned down into the injector, exerting a forward or downward force on main spring seat 104 and main spring 102 positioned therebelow. This compresses main spring 102 for the injection operation. As the compression of main spring 102 is completed, trigger spring seat 92, firing sleeve 94 and balls 96 move from the position shown in
At this point, injector 10 is ready to be loaded with medication, vaccine or other medicinal fluid. In order to retract the plunger and thereby draw fluid from a vial, injector 10 is held in an upright position with the vial at the top. Dosage knob 24 is then rotated in a counter clockwise direction, thereby drawing back slide bushing extension 36, slide bushing extension seat 38, slide bushing 88, firing sleeve 94, ram 108 and plunger 130. This draws fluid into chamber 132, thus preparing injector 10 for injection. This so-called ratchet-ready position is depicted in
Injector 10 cannot be fired until trigger locks 76 are both depressed, or in the event only one trigger lock is included, the injector cannot be fired until that single trigger lock is depressed. This provides a safety in order to prevent inadvertent firing. To fire injector 10 and inject fluid into the patient, trigger locks 76 are depressed, thereby releasing the engagement between trigger lock legs 80 and notch 82 in main body 12. This is done after orifice 142 of nozzle 140 is pressed against the skin of the patient receiving the injection. Thus, with the trigger locks depressed, injector 10 is pressed against the patient, causing trigger sleeve 14 to slide in a forward direction toward the patient to the position shown in
After the injection process is completed, trigger sleeve 14 is slid back to its original position by spring 32 so that trigger lock legs 80 engage notch 82 of main body, and cartridge lock 22 is rotated to permit sideways removal of nozzle 140. When injector 10 is to be reused, another nozzle is loaded in place and the process is repeated.
The injector of
Numbers corresponding to
Instead of notched head 114 in ram 108 of injector 10, the embodiment of
In operation, nozzle 240 is filled in the same manner as described above with respect to nozzle 140. Ram 208 is drawn back so that distal flange 214 contacts frangible member 216. Because the loading force is so small, perhaps as low as ten pounds or even five pounds or less, frangible member 216 will not break as plunger 230 is pulled back to draw injection fluid into chamber 232.
When the injection force is applied via ram 208, shoulder 215 of middle flange 213 drives through frangible member 216 before distal flange 214 contacts U-shaped proximal end 236 of plunger 230. Shoulder 215 and middle flange 213 close off enough of U-shaped proximal end 236 to prevent fragments of frangible member 216 and tabs 217 from falling out and potentially causing jamming of the various components.
After firing, nozzle 240 is removed from the injector as in the previously-described embodiments. A new nozzle, with an intact frangible member 216, is installed for the next injection. This prevents cross-contamination between patients. If, rather than replacing nozzle 240, the user attempts to reuse and reload the nozzle, the absence of frangible member 216 will cause distal flange 214 to merely pull out of U-shaped proximal end 236 as shown in
As with the first embodiment discussed above, it should be understood that it is possible to use this embodiment of
Another manner in which cross-contamination can be prevented is to use one of the loading vial adaptor systems described in the parent application. To avoid confusion, the numbering has been retained from the parent application.
Nozzle/filling assembly 280 typically is provided to the end user in a ready-to-fill state. In this state, the nozzle/filling assembly may be operatively engaged with vial adapter 282 to perform the filling operation, in which a dose of injectable fluid is drawn from vial 290 through injection orifice 300 and into fluid chamber 298 of nozzle 292. To allow the injection to go forward, filling adapter 294 is broken away from nozzle 292. Filling adapter 294 is specially configured to operatively engage with vial adapter 282 to perform the filling operation. Typically, the system is configured so that filling cannot occur after filling adapter 294 is broken away. Thus, a single simple step permits the injection to go forward, while simultaneously disabling the ability to refill nozzle 292.
Main body 284 of vial adapter 282 includes a vial gripping section 310 (see
Vial adapter 282 includes a piercing member or spike 321 configured to pierce a sealed opening of vial 290. Openings are provided on piercing member 321 to enable injectable liquid from vial 290 to flow into a central channel 326 defined within a cylindrical member 328 extending away from gripping section 310 between fingers 320 and 322. Plug 288 is fitted snugly into the distal end of cylindrical member 328. As indicated in
Referring specifically to
Inserting nozzle/filling assembly 280 into vial adapter 282 also causes a forward end of nozzle 292 to push against the distal end of inner valve sleeve 286. Prior to contact with nozzle 292, inner valve sleeve 286 is biased axially away the vial-gripping portion of vial adapter 282 by resilient feet 344 provided on the proximal end of inner valve sleeve 286. In this initial position, an annular protruded area 346 on the inner diameter of inner valve sleeve 286 seals channels 330 formed in plug 288, thereby preventing liquid from passing out of central channel 326.
The insertion of nozzle/filling assembly 280 into vial adapter 282 pushes the inner valve sleeve 286 axially toward vial 290, compressing feet 344 and moving the sleeve so that the annular protruded area 346 does not seal channels 330 (
After piston 296 has been withdrawn to draw in a dose of injectable fluid, filling adapter 294 may be broken away from nozzle 292. Typically, nozzle/filling assembly 280 is manufactured so that there is a frangible or breakable connection 360 between filling adapter 294 and nozzle 292 at the desired breaking point. Typically, after the filling adapter is broken away, it cannot be reattached to the nozzle by the user.
Referring now to
Because the flexible fingers act as a blocking mechanism or outer protective shroud that maintains nozzle 292 spaced apart from the end of inner valve sleeve 286, the respective fluid paths of vial adapter 282 and nozzle 292 are prevented from coming into contact, thereby guarding against contamination. Also, the nozzle is prevented from pushing against the end of inner valve sleeve 286, such that the nozzle cannot push the inner valve sleeve inward to disable the sealing of channels 330 by annular protruded area 346. Furthermore, because filling adapter 294 has been removed, a seal cannot be established to seal an enclosed area between the fluid paths. Accordingly, it should be appreciated that the removal of filling adapter 294 guards against contamination, prevents refilling and otherwise protects against unintended use.
As in the previous examples, the device depicted in
Also, nozzle/filling assembly 382 differs from that of
It will be appreciated that the nozzle/filling assembly 402 and vial adapter 400 provide similar advantages to the other embodiments discussed herein. In particular, filling adapter is configured so that it is frangibly connected to the nozzle, and must be broken away before an injection can be administered. As in the other embodiments, this breaking of the filling adapter prevents reuse by disabling the ability to refill the device. Specifically, once the filling adapter has been removed, the nozzle is no longer shaped to engage the opening of the vial adapter and actuate the adapter valve seal. Also, the vial adapter has an outer structure, as in previous embodiments, that acts as a protective shroud to protect the fluid pathway and reduce risk of contamination.
The operation of injector 510 can be understood by making reference to
In order to fire injector 510, trigger locks 576 are depressed, disengaging trigger lock legs 580 from notch 582 in main body 512. This permits the operator to slide trigger sleeve 514 forwardly on main body 512 as injector 510 is pressed against the patient. This releases main spring 602 as previously described, driving ram 608, ram extension 609 and plunger 630 forwardly or in a distal direction. This causes fluid to be ejected out orifice 642 and into the patient. This just-fired position of the components is shown in
To prepare injector 510 for the next injection, the winder (not shown) compresses main spring 602 using the ratcheting operation previously described. Alternatively, the continuous rotation embodiment of the winder mechanism can be substituted. A dosage knob (not shown), like dosage knob 24 of injector 10, is turned, and this retracts ram 608 and ram extension 609 mounted to it. This facilitates the remove and replacement of cartridge 520 through the side of injector 510 as previously described in connection with injector 10. Because the distal end of ram extension 609 is normally perfectly positioned to abut the proximal end of plunger 630, injector 510 is now ready for the next injection (as shown in
While various embodiments and arrangements of a needle-free injection system and method have been shown and described above, it will be appreciated that numerous other embodiments, arrangements, and modifications are possible and are within the scope of the invention. The foregoing description should be understood to include all novel and non-obvious combinations of elements described herein, and claims may be presented in this or a later application to any novel and non-obvious combination of these elements. The foregoing embodiments are illustrative, and no single feature or element is essential to all possible combinations that may be claimed in this or a later application.
This application is also a continuation-in-part of U.S. patent application Ser. No. 10/976,342 filed Oct. 26, 2004 and also claims the benefit of U.S. provisional patent application No. ______ filed Feb. 15, 2005 under Express Mail No. EV493217799US entitled Needle-Free Injection Device for Individual Users, which is hereby incorporated by reference in its entirety for all purposes.
Number | Date | Country | |
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Parent | 10976342 | Oct 2004 | US |
Child | 11069538 | Feb 2005 | US |