1. Field of the Invention
The present invention relates to a vial filling system and method for filling a vial of a needle-less injector used for the subcutaneous delivery of a dose of liquid formulation to a human or animal, and more particularly, to a filling adaptor for a vial of a needle-less injection device that delivers a high-pressure jet of fluid through the epidermis of the human or animal.
2. Description of Related Art
The advantage of needle-less injection devices has been recognized for some time. Some of these advantages include: the absence of a needle stick injuries that presents a hazard to healthcare workers; the risk of cross-contamination between humans or animals is reduced; the risk of needle breakage in the tissue of the human or animal is eliminated; and the jet of liquid medicament is generally smaller than the diameter of a hypodermic needle and thus is less painful than a hypodermic needle.
Because of the well-known advantages of needle-less injection, there are many pneumatic or gas actuated needle-less injection devices that are designed to provide multiple doses to patients or animals. Most known needle-less injection devices operate by using a piston to drive the fluid to be delivered though a fine nozzle that creates a small, high pressure stream that penetrates the skin simply due to the high pressure. Multi-dose devices depend on a source of air or working fluid that is used to operate the piston that drives the fluid through the nozzle. Thus, a serious limitation of these devices is that they must have a readily available source of air or other fluid to drive the piston. This makes these devices impractical for use in the hospitals or clinics, and the field, especially in remote areas.
Because of the disadvantages of injection devices that use high-pressure fluids to drive the piston, a great deal of attention has been given to the development of a spring-powered needle-less injection device. The success of the known devices has been limited, due to problems associated with safety and reliability. The issues regarding safety generally involve the possibility of accidental discharge of the device. And the problems of reliability generally involve the device's ability to deliver a full, known dose of the liquid being delivered into the animal or human.
Safety issues generally arise in association with devices that have exposed triggers or include a ram or piston driving device that can extend beyond the inner housing of the injector. The risk of using this type of device is similar to the risks associated with the triggers on firearms, and that is the inadvertent pressing of the trigger, can result in the accidental or premature firing of the device.
Reliability issues include a broad spectrum of problems. One significant problem is the creation of a suitable jet or stream of fluid and the introduction of this jet on to the skin of the animal or human. Preferably, the jet will be a very fine jet that will impact a section of taut skin at an angle of incidence of preferably 90 degrees. Most of the energy of the stream is used to penetrate the skin when the jet impacts at approximately 90 degrees to the skin. Additionally, by keeping the skin taut prior to delivering the jet of fluid, the skin is not allowed to flex, and thus more of the energy from the jet is used to penetrate the skin rather than deflecting or moving the skin.
There are also significant disadvantages related to the containment of the fluid formulations in needle-less injectors. The reservoir of the injector can include an amount of liquid formulation ample to deliver numerous injections. Individual doses of a liquid formulation can also be delivered via the injector. The individual doses can be provided in a plurality of reservoirs coupled to the delivery device. A disadvantage of these types of liquid formulation delivery is that the user must have a large supply of liquid formulation on hand for treating numerous patients or animals. This decreases the practicality and use of the injectors in numerous environments.
Providing the desired amount of liquid formulation in a pre-dosed disposable vial helps solve the above-mentioned problems. However, a need still exists for allowing these pre-dosed vials to be filled in the field.
According to one aspect of the present invention there is provided a hand-held, spring-powered, needle-less injector device that can deliver a dose of liquid, such as a medicament, both safely and reliably without an external power source.
In another aspect, the needle-less injector of the present invent prevents accidental discharge. The needle-less injector device has a trigger stop that prevents operation of the trigger when the inner housing in not in the firing position. An example of this trigger stop includes a protrusion that extends from the outer housing and impedes the movement of the trigger when inner housing is not in the firing position. The protrusion then moves away from the trigger when the inner housing is moved into the firing position.
In yet another aspect, the needle-less injector device of the present invention uses a single-use, disposable needle free vial containing a liquid for delivery. The vial includes a connector at one end and a nozzle and skin tensioner at the other end. The connector can be a bayonet type connector. The skin tensioner can be a ridge that surrounds the nozzle. The vial is easily insertable into the injector and provides for a safer healthcare environment.
It is still another aspect of the present invention to provide a field filling device that is attachable to the vial to enable the vial to be filled with a liquid from a bulk container to enable a vial to be filled with the desired dosage in the field.
Prior to injection, the user will attach a field filling adaptor to an empty vial. The adaptor is insertable into a bulk container of liquid formation. A plunger located in the vial draws the liquid into the vial until it is filled with the proper dosage amount. Thereafter the vial is removed from the adaptor and is ready to be inserted into the injector.
During operation of the injector, the user will position the ram at the cocked position and insert the vial into the leading end of the inner housing. The vial can be pre-filled with the liquid that is to be delivered to the animal or human as described above. Then the user presses the nozzle and skin tensioner against the animal or human, causing the inner housing of the device to move against the skin tensioning spring, into or relative to the outer housing to the firing position. Once the inner housing is moved to the firing position, the pressure of the skin tensioning spring is reacted against the animal or human, causing the skin to be stretched taut across the skin tensioner. This stretching of the skin across the skin tensioner will position the target area of the skin at a right angle to the vial and the nozzle. The movement of the inner housing to the firing position also results in the movement of a protrusion relative to the inner housing such that the protrusion no longer obstructs the movement of the trigger. The user then simply presses the trigger, which releases the ram, which in turn drives the fluid through the nozzle of the vial and into the animal or human's skin.
The ram may drive a separate plunger with a seal through the vial to expel the fluid in the vial through the nozzle of the vial. However, the ram may incorporate portions, or all, of the plunger. It is preferred that the ram will drive a separate plunger and seal will be used since this will enable the design of a one-time use plunger and seal.
Still further, it is contemplated that the use of a separate plunger will allow the use of a mechanical cocking device that will push against the ram to move the ram from an unloaded position to the cocked position.
According to these and other aspects there is provided a vial filling system for device for a needle-less injector including an adaptor. The adaptor has a housing including a top and a side wall extending downwardly from the top. A recess is disposed in the side wall of the adaptor for receiving a vial. An inlet opening is located in the top of the adaptor. When the vial is inserted into the recess the inlet opening is aligned with a nozzle of the vial. A needle extends from the top of the housing and is in communication with the inlet opening of the adaptor. The needle is constructed and arranged to pierce a container of liquid formulation. A plunger is movably disposed within the vial for drawing the liquid formulation from the container into the vial.
According to these and other aspects there is provided a filling adaptor for a vial of a needless injector. The adaptor includes a housing having a top and a side wall extending downwardly from the top. A recess is disposed in the side wall of the adaptor for receiving a vial. An inlet opening is located in the top of the adaptor, wherein when the vial is inserted into the recess the inlet opening is aligned with a nozzle of the vial. A needle extends from the top of the housing in communication with the inlet opening and the nozzle, wherein the needle is constructed and arranged to pierce a container of liquid formulation.
According to these and other aspects there is provided a method of filling a vial of a needless-injector device comprising the steps of providing a vial. The vial has opposed ends, one of the ends including a nozzle for receiving and ejecting liquid. A plunger is positioned within the other end of the vial. An adaptor is provided. The adaptor includes a recess for receiving the nozzle end of the vial and an inlet opening. A needle is in communication with the inlet opening. The adaptor is positioned on the nozzle end of the vial, wherein when the adaptor is positioned on the vial the nozzle, inlet opening and needle are in fluid communication. A source of liquid is pierced with the needle. The plunger is moved within the vial to draw the liquid from the source through the nozzle and into the vial. Thereafter, the adaptor is removed from the vial.
These and other objects, features, aspects, and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiment relative to the accompanied drawings, in which:
Referring to
As illustrated in
Inner housing 12 can be moved into the ready position of
The amount of pressure or force that is used to hold vial 18 against skin 22 is an important variable in the injection process. Needle-less injection devices are capable of delivering fluids through the skin 22 of the animal or human 24 by injecting a jet of fluid 34 into the skin 22 at a sufficiently high pressure and velocity so that fluid jet 34 penetrates through the skin 22 and into the tissue of the animal or human 24.
Important factors that contribute to the device's ability to accomplish the task of forming a jet of fluid 34 are the amount of energy that can be quickly and efficiently transferred to the fluid jet 34, and the device's ability to position the fluid jet 34 such that the energy of the jet is efficiently used to penetrate the tissue.
The energy to be transferred to fluid 20 is stored in an injection delivery spring 36 that drives a plunger and seal 38 into the vial 18 in order to force the fluid 20 through a nozzle 40 that forms the jet of fluid 34. Injection delivery spring 36 is positioned between a head 50 (
In order to obtain the most efficient delivery of the jet of fluid 34 into the skin 22 the nozzle 40 should be positioned at a right angle relative to the skin 22 as the jet of fluid 34 is delivered 22. Although the device may still operate at other angles, delivering the jet of fluid 34 at some angle other than a right angle could result in a component of the force with which the jet of fluid strikes the skin could be parallel to the skin rather than into the skin 22.
As illustrated in
As shown in
The amount of force required to be applied against the skin varies depending on the physical characteristics of the patient being injected with the device 10. For example, an older human may require higher force to hold the skin taut as compared to a young person, simply due to the effects of aging on the elasticity of the skin. Accordingly, it is contemplated that the disclosed invention can be manufactured with different skin-tensioning springs, each skin tensioning spring being of a stiffness that is appropriate for a particular application. It is contemplated that the force imposed by the skin tensioning spring may be made adjustable, for example by adding a threaded plug that screws against the spring to add pre-tension. However, it is preferred that the force imposed by the skin tensioning spring should not be adjustable or replaceable by the end user, but is preferably pre-calibrated during assembly. The outer housing 28 and a cocking and storage mechanism for use with the device 10 will be color coded to inform the user of the pre-set skin-tensioning force for that particular injector device 10.
Thus, in operation the user selects an injection device with the appropriate skin pre-tension spring 30 and injection delivery spring 36, and selects a vial 18 that will contain a desired fluid to be delivered into the tissue of the animal. The vial 18 will be attached to the leading end 14 of the inner housing 12, preferably through the use of a bayonet-type connector, and mated to a seal 38 that may be a part of the plunger and seal 38. The plunger 38 is driven through the vial 18 by spring powered ram 44 that is movable from a safe, cocked position, illustrated in
The variation of the skin pre-tension spring 30 and injection delivery spring 36 allows the needle-less injector device 10 to be tailored for a particular application. For example, a needle-less injector device 10 for use on a child would have one particular combination of skin pre-tension spring 30 and injection delivery spring 36, while the combination of skin pre-tension spring 30 and injection delivery spring 36 for an adult male would likely be a different combination. Accordingly, the disclosed invention can the adapted for use on a variety of animals or humans, and for the delivery of a variety of types injections or depth of delivery of the fluid by varying the skin pre-tension spring 30 and injection delivery spring 36.
Referring once again to
As illustrated in
In the preferred example of the invention, the movement of the inner housing 12 relative to the outer housing 28 moves the position of the trigger 45 (which is mounted from the inner housing 12) relative to the outer housing 28, which holds the protrusion 46. The amount of movement of the outer housing 28 relative to the inner housing 12 is accomplished against the force of the skin-tensioning spring 30.
The stiffness of the skin-tensioning spring 30 is selected such that the appropriate amount of force is imposed against the skin 22 of the animal or human 24. The stiffness of the skin-tensioning spring 30 is calculated from the well-known formula:
F=k*x,
where F is the required force at the firing position, x is the distance of travel of the inner housing 12 relative to the outer housing 28 to position the device in the firing position (where the protrusion 46 does not impede movement of the trigger mechanism 32), and k is the spring constant of the skin-tension spring 30.
Once the inner housing 12 is positioned relative to the outer housing 28 such that the desired amount of skin tensioning force is applied to the skin 22 against the vial 18, which also positions the device in the firing position, the pressing of the trigger 45 causes the release of the spring powered ram 44 from the cocked position only when the inner housing is in the firing position.
As shown in
Referring to
Cocking ram 62, when pushed against spring powered ram 44, moves the ram into the “ready” position illustrated in
Referring to
As shown in
As discussed supra, vial seal/plunger 38 is movably located within vial 18 to force the dose of medicament through the nozzle. Referring to
Plunger 38 includes a seal 37 located at its end. Seal 37 can be an o-ring or similar sealing device. Seal 37 creates a seal between plunger 38 and the inner wall of vial 18.
During operation, the user inserts the plunger 38 into vial 18 and moves the same within vial 18 using handle 84 until plunger 38 reaches the position shown in
The injector is placed into the cocking device and the lid is closed to “cock” the injector. The cocking device is also used as a storage compartment for the injector when not in use. Once the injector is “cocked”, the user will insert the pre-filled vial and seal into the opening in the end of the injector. The vial is designed to purge a small amount of liquid at the time of insertion so as to maintain the proper quantity of liquid for the injection. The vial will snap into place as it is rotated in the injector housing. The injector is now ready to use.
As described above, the user will press the face of the vial against the skin and depress the trigger to give the injection. The injector inner housing slides inside the outer housings, which creates an interlock so that the device cannot be operated until the proper tension against the skin is established. When the trigger is pressed, the trigger latch will release the hammer and the hammer will move the vial seal into the vial. The main pressure spring will deliver enough pressure to allow the liquid to pierce the skin.
After the injection has taken place, the vial is removed with the seal and discarded. The injector is then placed into the cocking mechanism and reloaded for the next injection.
The vial and seal assembly can be pre-filled or field filled with the use of an adapter and a break-away plunger. The current design is for a fixed dosage of 0.5 cc. When using the field filling device, the user will attach the field filling device to the vial, insert the break-away plunger into the vial, place the adapter into the bulk container and draw the liquid into the vial by pulling on the break-away plunger. When the vial is filled to the proper level, the user will snap the handle off of the break-away plunger, remove the vial from the adapter, and insert the vial into the injector housing. After the injection is complete, the user will remove the vial from the injector and discard. The plunger will be recessed into the vial and cannot be reused.
Plunger 38 and handle 84 can be made of a single piece of polycarbonate that has been injection molded or made by any other suitable manufacturing technique to allow the handle and plunger to be separated after the vial has been filled. Handle 84 enables the user to download the liquid to a desired level. Vial 18 can be formed of a clear material and could include indicia to aid the user. Moreover, the length of the plunger and handle can be varied to further control filling.
Although the present invention has been described in relation to particular embodiments thereof, many other variations and modifications and other uses will become apparent to those skilled in the art. It is preferred therefore, that the present invention be limited not by the specific disclosure herein, but only by the appended claims.
The present application is a continuation-in-part of U.S. patent application Ser. No. 11/121,439, entitled “Needle-less Injector,” filed May 30, 2002 and is related to U.S. patent application Ser. No. 11/185,736, entitled “Needless Injector and Ampule System,” filed Jul. 21, 2005.
Number | Date | Country | |
---|---|---|---|
Parent | 11121439 | May 2005 | US |
Child | 11453248 | Jun 2006 | US |
Parent | 11185736 | Jul 2005 | US |
Child | 11453248 | Jun 2006 | US |