Medication auto-injector and associated cartridge
Patent Information
- Application Number
- CN202580023771.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2024-02-05
- Filing Date
- 2025-02-04
- Publication Date
- 2026-11-03
AI Technical Summary
Existing automated drug injectors are single-use, resulting in large amounts of waste, serious environmental pollution, and difficulty in ensuring accurate drug dosage and safety, while also being costly.
Design an automatic drug injector with interchangeable cartridges. The cartridge is pre-filled with drug and can be separated from the syringe. It can be replaced after injection, and the syringe can be reused. It ensures injection under sterile conditions and enables drug flow through transverse channels and longitudinal grooves.
This technology enables the reusability of automated drug injectors, reduces environmental pollution, ensures accurate drug dosage and safety, and lowers costs.
Smart Images
Figure CN123036124A_ABST
Abstract
Description
Technical Field
[0001] This invention generally relates to the technical field of automatic drug injectors. More specifically, this invention relates to an automatic drug injector (particularly for life-saving drugs, such as epinephrine or adrenaline) and a related cartridge. Background Technology
[0002] Automated medication injectors are known to allow users (even those who are not particularly experienced) to administer medications, often life-saving, to themselves immediately, completely independently, and without the assistance of a healthcare professional. These automated medication injectors are practical and easy for end-users to use, thus saving public healthcare resources.
[0003] Known types of automatic drug injectors typically include a tubular housing in which a syringe equipped with a needle and a piston is slidably housed. The syringe is pre-filled with the drug to be administered. The tubular housing has a distal end enclosed by a cap (i.e., the end where the syringe needle is housed), while a button for operating the automatic injector (typically a spring-loaded button) protrudes from the proximal end of the tubular housing.
[0004] In use, the user continues by removing the cap and pressing the distal end of the autoinjector's tubular housing against his or her skin to keep the autoinjector vertical. Next, the user presses a button, releasing the syringe and associated piston, which then slides sequentially to withdraw the needle from the tubular housing, allowing it to pierce the user's body and inject the medication. The needle returns to the tubular housing by releasing the pressure of the distal end against the skin.
[0005] In another known type of automatic drug injector, instead of being housed in a tubular casing, the syringe is housed in a cartridge consisting of an inner casing and an outer casing that slide over each other. In this case, an unlock button is activated by pressing the distal end of the inner casing (from which the syringe needle will emerge) against the user's skin at the point of injection, causing the outer casing to slide forward over the inner casing. Pressing the thus unlocked button releases the syringe and its plunger, which then slide sequentially to allow the needle to penetrate and then inject the drug. The needle returns to the cartridge by stopping the pressure of the distal end of the inner casing against the skin.
[0006] While the known drug autoinjectors briefly described above have significant advantages in terms of safety of use, they still have some drawbacks.
[0007] First, these automated syringes are single-use. This means that once the medication inside the syringe has been injected, the syringe must be discarded. This leads to problems related to the large amount of waste generated and the costs of waste disposal. Furthermore, once used, single-use syringes are not easily recyclable and therefore pollute the environment.
[0008] Secondly, due to the dimensional tolerances in the manufacture of syringes, it is almost impossible to guarantee the injection of all the drugs contained in the syringe. This is particularly problematic for drugs such as heparin or certain vaccines, where the dosage must be injected with extreme precision.
[0009] Similarly, most current drug autoinjectors that provide this level of safety for patients have proven to be structurally complex, resulting in a cost that is difficult to reconcile with the cost of disposable devices. Summary of the Invention
[0010] Therefore, the main objective of this invention is to provide an auto-injector for drugs, particularly life-saving drugs or drugs that need to be administered immediately in any situation, which overcomes or at least limits the disadvantages associated with the known types of disposable auto-injectors for drugs described above.
[0011] More specifically, the main objective of this invention is to provide an auto-injector for medication that is configured in such a way that it can be reused once the medication it contains has been injected.
[0012] Another object of the present invention is to provide an autoinjector for medication, which is configured in such a way that it allows for the injection of different types of medications, especially medications that need to be injected immediately when the patient feels the need.
[0013] Another object of the present invention is to provide an autoinjector for a drug that is configured in such a way that it allows for immediate injection under sterile conditions.
[0014] Another object of the present invention is to provide an autoinjector for medication that is configured to prevent accidental triggering due to improper use, making it safe and easy to use even by inexperienced persons.
[0015] Another object of the present invention is to provide an autoinjector for a drug that is configured in such a way as to allow the systematic injection of a defined dose of drug.
[0016] Last but not least, the object of the present invention is to provide an autoinjector for medication that has a simplified design and therefore a cost price compatible with that of disposable devices.
[0017] Therefore, in its first aspect, the present invention relates to an autoinjector for a drug, the autoinjector comprising a tubular housing and an actuating device housed within the tubular housing.
[0018] The automatic drug injector is characterized by including an interchangeable cartridge also housed in a tubular casing, the interchangeable cartridge comprising: a container body having a proximal end and a distal end, the distal end being closed by a wall with an orifice formed in the wall, the orifice being tightly sealed by a membrane; a first rubber member for sealing the proximal end of the container body; and a needle integral with a support member suitably spaced apart from the first rubber member such that a first chamber containing the drug to be injected is defined between the first rubber member and the support member, and a second chamber receiving the needle is also defined between the support member and the wall of the distal end of the closed container body.
[0019] The cartridge has a device at the proximal end of the container body for removably attaching to a tubular housing for use with an automatic drug injector.
[0020] At least one transverse channel is formed in the support for the needle, and at the distal end of the container body, on the inner surface of the container body, at least one longitudinal groove is formed, each transverse channel and each longitudinal groove allowing the passage of a drug during injection.
[0021] The support for the needle can be operated by an operating device to slide tightly within the container body, such that the needle is transferred from a non-operational position to an operating position in which the needle is housed within a second chamber, and in which the needle is withdrawn from the container body of the cartridge in the operating position.
[0022] In a second aspect, the present invention relates to a cartridge for use with an autoinjector as defined above. The cartridges are interchangeable and include: a container body having a proximal end and a distal end, the distal end being closed by a wall with an orifice formed in the wall, the orifice being tightly sealed by a membrane; a first rubber member for sealing the proximal end of the container body; and a needle integral with a support member for tightly sliding within the body, wherein the support member is suitably spaced from the first rubber member such that a first chamber containing the drug to be injected is defined between the first rubber member and the support member, and a second chamber receiving the needle is also defined between the support member and the wall of the distal end of the closed container body.
[0023] The cartridges are interchangeable and have a device at the proximal end of the container body for removable attachment to an auto-injector.
[0024] At least one transverse channel is formed in the support for the needle, and at the distal end of the container body, on the inner surface of the container body, at least one longitudinal groove is formed, each transverse channel and each longitudinal groove allowing the passage of a drug during injection.
[0025] Preferred aspects of the invention are set forth in the dependent claims.
[0026] Due to its specific configuration, particularly the presence of a cartridge pre-filled with medication and equipped with a sterile needle (which is interchangeable and removably connected to the tubular housing), the automatic drug injector according to the invention can be reused. In fact, the used cartridge can be simply removed and replaced with a new one. In other words, the actuation device of the automatic drug injector can be used several times, and the cartridge is interchangeable; that is, once it has been emptied of its medication, it must be removed and replaced with a new cartridge. Since the cartridge is the only part that needs to be replaced after use, the disposal costs of the drug injector and its impact on environmental pollution are minimized.
[0027] In addition, due to the special configuration of interchangeable cartridges, the autoinjector allows for immediate injection and injection of a defined dose of medication under the most stringent aseptic conditions.
[0028] In the following description and in the appended claims, the term "distal" will refer to the portion of the autoinjector component disposed on the side of the autoinjector needle, while the term "proximal" will refer to the portion of the autoinjector component disposed on the opposite side of the autoinjector needle.
[0029] Furthermore, in the following description and in the appended claims, the term "used cartridge" will refer to a cartridge that has been emptied of the drug that has been injected by the autoinjector, while the term "new cartridge" will refer to a cartridge pre-filled with the drug to be injected by the autoinjector.
[0030] Finally, regarding the interpretation of the accompanying drawings, various orientations such as "up," "down," "left," "right," "front," "rear," etc., are used, and therefore components can be oriented differently, for example during transport and production as well as during operation. Attached Figure Description
[0031] The invention is described below with reference to certain examples provided by way of non-limiting example and illustrated in the accompanying drawings. These drawings illustrate different aspects and embodiments of the invention, and where appropriate, reference numerals illustrating structures, components, materials and / or similar elements in different drawings are indicated by similar reference numerals.
[0032] Figure 1 This is a longitudinal sectional perspective view of a drug autoinjector according to a preferred embodiment of the present invention.
[0033] Figure 2 yes Figure 1 A longitudinal cross-sectional view of the actuation device of an autoinjector, which is housed in a non-operational position inside the autoinjector.
[0034] Figure 3 yes Figure 1 A longitudinal cross-sectional view of the cartridge of an automatic drug injector.
[0035] Figure 4 This is a partial perspective view of the distal end of a cartridge according to another embodiment of the invention in an operational position, in which the needle is removed from the cartridge but the drug has not yet been injected.
[0036] Figure 5 yes Figure 4 A longitudinal sectional view.
[0037] Figure 6 This is a partial longitudinal cross-sectional view of the distal end of the cartridge in an operational position according to another embodiment of the invention, in which the needle is removed from the cartridge but the drug has not yet been injected.
[0038] Figure 7 This is a longitudinal cross-sectional view of the automatic drug injector according to the invention in the operating position, in which the needle is removed from the cartridge but the drug has not yet been injected.
[0039] Figure 8 This is a longitudinal cross-sectional view of the automatic drug injector according to the invention in another operational position, in which the drug contained in the cartridge has been injected. Detailed Implementation
[0040] While the invention is susceptible to various modifications and alternative constructions, certain preferred embodiments are illustrated in the accompanying drawings and described in detail below. It must be understood in any event that there is no intention to limit the invention to the specific embodiments illustrated; rather, the invention is intended to cover all modifications, substitutions, and equivalent constructions falling within the scope of the invention as defined in the claims.
[0041] Unless otherwise indicated, the use of “e.g.,” “etc.,” or “or” indicates a non-exclusive alternative and is not limited. Unless otherwise indicated, the use of “including” means “including, but not limited to”.
[0042] refer to Figures 1 to 3 These illustrate an auto-injector for drugs according to a preferred embodiment of the invention.
[0043] An auto-injector (generally referred to by reference numeral 100) includes a tubular housing 10, an actuation device 20, and a cartridge 30, which are vertically housed in the tubular housing 10 and coaxial with the tubular housing 10.
[0044] More specifically, the tubular housing 10 is preferably manufactured by injection molding of a plastic material, and defines within the tubular housing a proximal cavity 11 (generally cylindrical in shape) for accommodating the actuating device 20 and a distal cavity 12 (also generally cylindrical in shape) for accommodating the cartridge 30. Between the proximal cavity 11 and the distal cavity 12, the tubular housing 10 has a circumferential recess 13. An annular seat 14 is formed in the circumferential recess 13, the function of which will become clearer later in this description.
[0045] like Figure 2 As shown in detail, the actuation device 20 includes a plunger 21, which is also preferably made by injection molding of a plastic material, and the plunger includes a rod 22 having a proximal end 22a and a distal end 22b. A head 23 extends radially outward from the distal end 22b of the rod 22 of the plunger 21.
[0046] The actuating device 20 further includes a trigger element 24, which is received at the proximal end 10a of the tubular housing 10. A seat 24a is formed in the trigger element 24, facing the proximal cavity 11 that receives the actuating device 20, and is designed to be in position when the actuating device is in Figure 1 and Figure 2 The non-operating position shown is the proximal end 22a of the rod 22 that houses the plunger 21. The trigger element 24 is also preferably made by plastic injection molding. A coiled spring 25 surrounds and is coaxial with the rod 22 of the plunger 21. The spring 25 is also held by the trigger element 24.
[0047] A shoulder 23a is present in the head 23 of the plunger 21, which abuts against the abutment surface 14a of the seat 14 of the tubular housing 10 in the non-operating position of the actuating device 20. Furthermore, in the non-operating condition, a helical spring 25 is compressed between the trigger element 24 and the head 23 of the plunger 21 of the actuating device 20.
[0048] like Figure 3As shown in detail, the cartridge 30 includes a generally cylindrical container body 31 having a proximal end 31a and a distal end 31b. The proximal end 31a of the container body 31 has an opening 32, which is tightly closed by a first rubber member 33a or a proximal rubber member, preferably made of brominated butyl rubber. The distal end 31b of the container body 31 is closed by a wall 34 in which an orifice 34a is formed, which is tightly closed by a membrane 35. The membrane's function is to keep the contents of the cartridge 30 sterile when the actuation device 20 of the autoinjector 100 is operated, but at the same time allows the needle 40 to exit the cartridge 30. Preferably, the sealing membrane 35 of the orifice 34a is formed of a thin layer of aluminum or injection-molded plastic or any other material that maintains the sterility of the interior of the cartridge 30, and is applied (e.g., welded or glued) to the outer surface 34c of the wall 34 at the orifice 34a. As a result, the cartridge 30 is completely sealed to ensure the sterility of all its internal parts (including the needle 40), which must penetrate the user's body when in use.
[0049] For example, the sterilization of cartridge 30 is carried out by gamma rays. For this purpose, the container body 31 is preferably made of a material suitable for gamma ray sterilization, such as cyclic olefin polymer (COP) and cyclic olefin copolymer (COC) materials.
[0050] Inside the container body 31 of the cartridge 30, there is also a second rubber element 33b or a distal rubber element, preferably made of brominated butyl rubber, which has the same dimensions as the first rubber element 33a and is appropriately spaced apart from it. The first rubber element 33a and the second rubber element 33b are positioned opposite each other inside the cartridge 30, i.e., such that corresponding or homologous surfaces 36a and 36b face each other.
[0051] A first chamber 37a or proximal chamber containing the drug F to be injected by means of the autoinjector 100 is defined between the first rubber member 33a and the second rubber member 33b, precisely between the corresponding facing surfaces 36a and 36b. A second chamber 37b or distal chamber for receiving the needle 40 is defined between the second rubber member 33b and the wall 34 of the distal end 31b of the container body 31 of the enclosed cartridge 30.
[0052] The needle 40 is supported by a support 41, which is configured to slide tightly inside the container body 31 of the cartridge 30.
[0053] exist Figures 1 to 5 , Figure 7 and Figure 8In the embodiment illustrated in the figure, the support 41 includes: a first cylindrical portion 41a having an outer diameter slightly smaller than the inner diameter of the container body 31, i.e., allowing the support 41 to slide snugly into the container body 31 of the cartridge 30; followed by a second portion 41b configured to engage (preferably screw into) an opening 38b formed in a second rubber member 33b on a side opposite to the surface 36b. Thus, the needle 40 is integral with the second rubber member 33b and has a tip 42 facing and appropriately spaced from the membrane 35 (e.g., a few millimeters apart). A transverse channel 43 exists between the first portion 41a and the second portion 41b of the support 41 for the needle 40; the function of this transverse channel will become clearer later in the description. Without departing from the scope of the invention, it is possible to provide more than one transverse channel 43 between the first portion 41a and the second portion 41b of the support 41 for the needle 40.
[0054] Preferably, a gasket 47 (e.g., an O-ring) is provided on the surface 41c of the wall 34 of the distal end 31b of the container body 31 facing the closed cartridge 30 of the support 41 for the needle 40. The function of the gasket is to prevent the drug F from leaking into the cartridge during auto-injection.
[0055] Preferably, an additional washer 48 (e.g., an O-ring) is disposed on the outer surface of the first portion 41a of the support 41 to facilitate tight sliding of the support 41 within the cartridge 30. The washer 48 also serves to prevent leakage of the drug F.
[0056] Figure 6 An alternative embodiment of the cartridge according to the invention is shown, in which a second rubber element is not provided, and the needle 40 is integral with a support 41' configured to slide tightly within the cartridge. For this purpose, the support 41' has one or more washers 48'a and 48'b (e.g., O-rings) at one of its outer surfaces. Washers 48a' and 48b' also serve to prevent leakage of the drug F.
[0057] Further, preferably, a gasket 47' (e.g., an O-ring) is provided on the surface 41'c of the wall 34 of the distal end 31b of the container body 31 facing the closed cartridge 30 of the support 41' for the needle 40. The function of this gasket is to prevent the drug F from leaking into the cartridge during auto-injection. A transverse channel 43' is provided in the support 41' of the needle 40, the function of which will become clearer later in this description.
[0058] The cartridge 30 is removably connected to the tubular housing 10 of the autoinjector. For this purpose, a circumferential protrusion 39 is formed at the proximal end 31a of the container body 31 of the cartridge 30, as shown in... Figure 1As can be seen, the circumferential protrusion is adapted to be inserted into a seat 14 formed in the tubular housing 10 of the drug autoinjector 100 during use, and the head 23 of the plunger 21 is also accommodated in the seat under non-operational conditions.
[0059] In the connected position, the cartridge 30 is vertically positioned in the distal cavity 12 of the tubular housing 10 and coaxial with the tubular housing 10, wherein the second chamber 37b accommodates the needle 40, which preferably protrudes from the tubular housing 10.
[0060] Specifically, the circumferential protrusion 39 of the cartridge 30 is inserted into the annular seat 14 of the tubular housing 10 via a snap-fit engagement, for example, by rotating the cartridge 30 to activate the snap-fit connection. In this case, a flat portion (not visible in the figure) is formed in the circumferential protrusion 39. In this way, the cartridge 30 is securely attached to the tubular housing 10 of the drug injector 100 without causing accidental impact or misuse that could lead to the cartridge 30 separating from the drug injector 100.
[0061] The cartridge 30 has a container body 31 at its distal end 31b with at least one longitudinal groove 44 formed on its inner surface. In the embodiment illustrated, a plurality of longitudinal grooves 44 are provided that are parallel to each other and equally spaced to form an annular ring on the inner surface of the container body 31. Importantly, the longitudinal dimensions and positions of one or more grooves 44 are such that, during injection of the drug F, the first chamber 37a of the cartridge 30 containing the drug F to be injected is positioned in fluid communication with a transverse channel 43, which in turn is in fluid communication with a needle 40. More specifically, the transverse channels 43, 43' and the longitudinal grooves 44 are formed in the cartridge 30 such that the planes of symmetry of the transverse channels 43, 43' and the planes of symmetry of the longitudinal grooves 44 coincide. Under these conditions, in effect, the transverse channels 43, 43' and the longitudinal grooves 44 are in communication, and the drug F can flow from one to the other, such that the first chamber 37a containing the drug F is in fluid communication with the needle 40.
[0062] Specifically, each longitudinal groove 44 has a length at least equal to the thickness of the second rubber member 33b plus the amount required to connect the transverse channel 43 formed in the support member 41 for the needle 40 to the first chamber 37a containing the drug F to be injected. Furthermore, and as in... Figure 7 As can be seen, the longitudinal groove 44 is positioned on the inner surface of the container body 31 of the cartridge 30 in such a way that when the first part 41a of the support member 41 for the needle 40 abuts against the inner surface 34b of the wall 34 of the distal end 31b of the closed container body 31, the second rubber member 33b of the cartridge 30 is located at the longitudinal groove 44.
[0063] Figure 4 and Figure 5Details of a cartridge according to an alternative embodiment of the invention are shown below. This cartridge is similar to that described above and... Figure 3 The cartridge 30 shown in the diagram is entirely similar, except that the cartridge body 31 has an annular extension 45. Specifically, the annular extension 45 extends from the wall 34 of the distal end 31b of the closed cartridge body 31 and is provided with an opening 46. Therefore, in use, specifically when the autoinjector 100 is pressed against the user's skin, the air present in the second chamber 37b advantageously flows outward through the opening 46 of the annular extension 45, allowing the needle 40 to penetrate the skin more easily.
[0064] During production, cartridge 30 must be filled with medication using a suitable filling machine. For this purpose, three filling modes exist for filling cartridges.
[0065] According to the first filling mode, in the container body 31 (which has a membrane 35 with a sealed hole 34a for the needle 40 to exit through), the second rubber member 33b-needle support 41-needle 40 assembly is inserted into the correct vertical position. In this correct position, the needle 40 is vertically accommodated in the second chamber 37b of the cartridge 30.
[0066] Next, the first chamber 37a of the container body 31 is filled with a desired volume of drug F and sealed with a first rubber member 33a. Preferably, and to facilitate insertion of the first rubber member 33a into the container body 31 filled with drug F, a hole (not shown) is made in the first rubber member 33a to allow air to escape between the first rubber member 33a and the drug F contained in the first chamber 37a of the cartridge 30. Finally, the hole made in the first rubber member 33a is sealed with a stopper (also not shown) to prevent drug F from escaping.
[0067] According to the second filling mode, in the container body 31 (the membrane 35 already provided with the outlet hole 34a of the sealing needle 40), the second rubber part 33b-needle support 41-needle 40 assembly is inserted into the correct vertical position. In this correct position, the needle 40 is vertically accommodated in the second chamber 37b of the cartridge 30.
[0068] Next, the first rubber component 33a is inserted into place and pierced with a dual-channel needle (essentially a stainless steel conduit). Drug F enters through one channel of the conduit, while air escapes through the other. Once filling is complete, the needle-conduit is removed, and the hole made in the first rubber component 33a by the needle-conduit is plugged, preventing drug F from escaping from the cartridge.
[0069] The third mode of filling cartridge 30 with drug F is best suited for current filling machines.
[0070] In practice, within the container body 31 (the membrane 35 already provided with the outlet orifice 34a of the sealing needle 40), the second rubber member 33b-needle support 41-needle 40 assembly is inserted into the correct vertical position. In this correct position, the needle 40 is vertically accommodated in the second chamber 37b of the cartridge 30.
[0071] Subsequently, and before the insertion of the first rubber element 33a, a vacuum is created in the first chamber 37a of the container body 31, thereby holding the second rubber element 33b-needle support 41-needle 40 assembly in place, ensuring complete air escape. Then, under negative pressure, the drug F is injected into the first chamber 37a, and the second rubber element 33b-needle support 41-needle 40 assembly shifts to its initial position, with the needle tip 42 near and sufficiently away from the membrane 35 to prevent it from piercing the membrane 35 before the user actuates the autoinjector 100. At this time, the first rubber element 33a is still inserted under negative pressure.
[0072] The operation of the automatic drug injector 100 according to the present invention will be obvious to those skilled in the art, and has been described and will be referenced below. Figure 7 and Figure 8 To state the content based thereon. Refer to the description above and... Figure 3 The illustration of the type of cartridge 30 in the diagram is used to describe this operation, but it should be understood that essentially similar arguments exist in... Figure 6 This applies to the case of the cartridge shown in the diagram.
[0073] As described above, in Figure 1 In the non-operational position of the drug autoinjector 100 shown, a helical spring 25 is compressed between the trigger element 24 and the head 23 of the plunger 21 of the actuation device 20. Additionally, the head 23 of the plunger 21 is housed in a seat 14 of a tubular housing 10, which faces and is spaced a few millimeters from the first rubber element 33a housed in the housing 31 of the cartridge 30.
[0074] Now suppose a user wants to administer drug F, which is contained in cartridge 30 of an auto-injector 100, to himself / herself.
[0075] First, the user grasps the tubular casing 10 and positions the autoinjector 100, pressing the distal end 31b of the cartridge 30's container body 31 against his or her skin surface, such that the longitudinal axis of the cartridge 30 is perpendicular to the skin surface. The user then activates the autoinjector 100 by pressing the trigger element 24 in the direction of the press. As a result of the pressure applied to the trigger element 24, the trigger element releases the helical spring 25, which extends and pushes the plunger 21 forward, along with it, the first rubber member 33a of the cartridge 30, i.e., into the first chamber 37a of the cartridge 30.
[0076] When the head 23 of the plunger 21 pushes the first rubber member 33a, the first rubber member transmits motion to the second rubber member (or directly to the support member 41' in the absence of the second rubber member) by means of the drug F inserted between the first rubber member and the second rubber member 33b. As a result, the needle 40, carried by the support member 41 integral with the second rubber member 33b (or directly by the support member 41' in the absence of the second rubber member), moves forward until it perforates the membrane 35, which seals the hole 34a formed in the wall 34 of the cartridge 30.
[0077] More specifically, when the user activates the auto-injector 100, the plunger 21, moved by the helical spring 25, pushes the first rubber member 33a upward. Because of the presence of the drug F (i.e., an incompressible liquid) between the first rubber member 33a and the second rubber member 33b (or, in the absence of the second rubber member, the support member 41'), and the needle 40 integrated with the support member, the entire system inside the container body 31 of the cartridge 30 (i.e., the first rubber member 33a, the drug F present in the first chamber 37a, the second rubber member 33b and the support member 41 (or, in the absence of the second rubber member, the support member 41') connected to it, and the needle 40 integral with the support member) moves forward by a certain amount (typically a few millimeters), causing the tip 42 of the needle 40 to pierce the membrane 35. In fact, the air contained in the second needle receiving chamber 37b is compressible.
[0078] Once the membrane 35 has been perforated, the air contained in the second chamber 37b of the cartridge 30 can escape from the second chamber 37b through the hole 34a formed in the wall 34, thereby allowing the needle 40 to move further forward until it is completely withdrawn from the cartridge 30.
[0079] Figure 7 The diagram illustrates the operational conditions under which the first portion 41a of the needle support 41 abuts against the inner surface 34b of the container body 34, and the needle 40 is fully withdrawn from the cartridge 30. Because the cartridge 30 is pressed against the user's skin and the longitudinal axis of the cartridge 30 is perpendicular to the user's skin surface, the needle 40 can pierce the skin to deliver an injection into the user's muscle to its maximum permissible depth.
[0080] At this time, and as in Figure 8 As can be seen, the plunger 21 pushes the first rubber member 33a forward until it is adjacent to the second rubber member 33b. As the first rubber member 33a moves toward the second rubber member 33b, the drug F is injected into the user's body through the needle 40, passing through the transverse channel 43 formed in the support member 41 of the needle 40 and the longitudinal groove 44 formed on the inner surface of the container body 31.
[0081] When the injection is complete, the user can proceed to remove the used cartridge 30 from the autoinjector 100 and insert a new cartridge into the autoinjector 100. Preferably, the needle 40 can be covered with a cap (not shown) before the used cartridge 30 is removed from the autoinjector. This is to prevent accidental injection. As an alternative to the cap, the needle 40 can be fitted with a spring-loaded cap (not shown) that retracts when the autoinjector 100 is pressed against the user's skin and extends to cover the needle 40 when the autoinjector is moved away from the skin at the end of the injection.
[0082] Before inserting a new cartridge 30, the actuator 20 must be manually reset to its non-operating position. To do this, the user, acting on the head 23, pushes the plunger 21 backward, thereby compressing the spring 25, until the proximal end 22a of the rod 22 of the plunger 21 is seated in the seat 24a of the trigger element 24 and the head 23 of the plunger 21 is seated in the annular seat 14 of the tubular housing 21, wherein the shoulder 23a abuts against the abutting surface 14a of the seat 14.
[0083] Once the actuation device 20 has been re-armed, the new cartridge 30 is vertically inserted into the tubular housing 10 of the automatic injector 100 until the circumferential protrusion 39 engages with the annular cavity 14 formed in the tubular housing 10 between the first cavity 11 and the second cavity 12. Thus, the new cartridge 30 is securely attached to the automatic injector 100 without the risk of accidental detachment or misuse.
[0084] From the above description, the intended characteristics of the autoinjector for pharmaceuticals according to the present invention are clear, as are its relative advantages. In particular, once injected with the drug contained in the autoinjector according to the present invention, the autoinjector can be reused, thus being sustainable in terms of environmental pollution. Furthermore, the autoinjector described above allows for the immediate injection of different types of drugs under conditions of maximum asepticity and safety. Again, manufacturing and assembly costs are very well controlled. Several component elements are indeed easy to manufacture and involve assembly along a single axis.
[0085] Finally, it is clear that the envisioned automated drug injector is susceptible to numerous modifications and variations; furthermore, all details can be replaced with other technically equivalent components. In practice, the materials used and their dimensions can be of any type depending on the technical requirements.
Claims
1. An automatic drug injector (100) comprising a tubular housing (10) and an actuation device (20) housed within the tubular housing (10). Its features are, It includes interchangeable cartridges (30) also housed in the tubular casing (10), the interchangeable cartridges comprising: - A container body (31) having a proximal end (31a) and a distal end (31b), the distal end being closed by a wall (34) with an opening (34a) formed in the wall, the opening being tightly closed by a membrane (35); - A first rubber component (33a) is used to seal the proximal end (31a) of the container body (31). - A needle (40) integral with a support (41; 41'), the support being appropriately spaced from the first rubber member (33a) such that a first chamber (37a) containing the drug (F) to be injected is defined between the first rubber member (33a) and the support (41), and a second chamber (37b) accommodating the needle (40) is also defined between the support (41) and the wall (34) that closes the distal end (31b) of the container body (31); The cartridge (30) has a device (39) at the proximal end (31a) of the container body (31) for removably connecting to the tubular housing (10) of the drug auto-injector (100). At least one transverse channel (43; 43') is formed in a support (41; 41') for the needle (40), and at least one longitudinal groove (44) is formed on the inner surface of the container body (31) at the distal end (31b) of the container body (31). The at least one transverse channel (43; 43') and the at least one longitudinal groove (44) allow the drug (F) to pass through during the injection. The support (41; 41') for the needle (40) is operable by the operating device (20) to slide tightly within the container body (31), such that the needle (40) is transferred from a non-operational position to an operational position in which the needle is contained within the second chamber (37b) and in the operational position in which the needle is withdrawn from the container body (31) of the cartridge (30).
2. The auto-injector (100) according to claim 1, wherein, The tubular housing (10) defines a proximal cavity (11) for accommodating the actuating device (20) and a distal cavity (12) for accommodating the cartridge (30). A circumferential recess (13) is located between the proximal and distal cavities, and an annular seat (14) is formed in the circumferential recess. The removable coupling device of the cartridge (30) consists of a circumferential protrusion (39) formed at the proximal end (31a) of the container body (31) of the cartridge (30) and adapted to snap into the annular seat (14).
3. The autoinjector (100) according to claim 1 or 2, wherein, The actuation device (20) includes: a plunger (21) including a rod (22) with a head (23) extending radially outward from the distal end (22b) of the rod; and a spring (25) positioned around and coaxial with the rod (22) of the plunger (21).
4. The autoinjector (100) according to claim 3, when subordinate to claim 2, wherein, A shoulder (23a) is formed in the head (23) of the plunger (21), wherein the shoulder (23a) abuts the adjacent surface (14a) of the seat (14) of the tubular housing (10) in the non-operating position of the actuating device (20).
5. The autoinjector (100) according to claim 3 or 4, wherein, The actuation device (20) further includes a trigger element (24) housed at a proximal end (10a) of the tubular housing (10), wherein the spring (25) is held by the trigger element (24), and wherein a seat (24a) is formed in the trigger element (24) to house a proximal end (22a) of the rod (22) of the plunger (21) when the operating device (20) is in the non-operating position.
6. The auto-injector (100) according to any one of the preceding claims further includes a second rubber element (33b), wherein, The support (41) for the needle (40) includes a first cylindrical portion (41a) and a second portion (41b), the second portion being configured to engage with an opening (38b) formed in the second rubber member (33b), and the at least one transverse channel (43) being formed between the first portion (41a) and the second portion (41b) of the support (41) for the needle (40).
7. The autoinjector (100) according to any one of the preceding claims, wherein, At least one gasket (48; 48a', 48b') is present on the outer surface of the support (41; 41') for the needle (40) to facilitate tight sliding inside the cartridge (30) and prevent leakage of the drug (F), and wherein, on the surface of the closed wall (34) of the distal end (31b) of the container body (31) of the support (41; 41') for the needle (40) facing the cartridge (30), there is a gasket (47; 47') to prevent leakage of the drug (F).
8. The autoinjector (100) according to claim 6, wherein, The first rubber component (33a) and the second rubber component (33b) are positioned inside the cartridge (30) so that their corresponding surfaces (36a, 36b) face each other.
9. The autoinjector (100) according to any one of the preceding claims, wherein, An annular extension (45) extends from the outer surface (34c) of the wall (34) of the distal end (31b) of the container body (31) that encloses the cartridge (30), wherein an air escaping opening (46) is formed in the annular extension (45).
10. A cartridge (30) for use in an auto-injector (100) according to any one of the preceding claims, said cartridge (30) comprising: - A container body (31) having a proximal end (31a) and a distal end (31b), the distal end being closed by a wall (34) with an opening (34a) formed in the wall, the opening being tightly closed by a membrane (35); - A first rubber component (33a) is used to seal the proximal end (31a) of the container body (31). - A needle (40) integral with a support (41; 41'), the support sliding tightly within the container body (31), wherein the support (41; 41') is appropriately spaced from the first rubber member (33a) such that a first chamber (37a) containing the drug (F) to be injected is defined between the first rubber member (33a) and the support (41; 41'), and a second chamber (37b) accommodating the needle (40) is also defined between the support (41; 41') and the wall (34) that closes the distal end (31b) of the container body (31); The cartridge (30) is interchangeable, and the container body (31) has a device (39) at its proximal end (31a) for removably connecting to a tubular housing (10) of the automatic drug injector (100); and At least one transverse channel (43; 43') is formed in the support (41; 41') for the needle (40), and at least one longitudinal groove (44) is formed on the inner surface of the container body (31) at the distal end (31b) of the container body (31), the at least one transverse channel (43; 43') and the at least one longitudinal groove (44) allowing the drug (F) to pass through during the injection.
11. The cartridge case (30) according to claim 10, wherein, The removable coupling device of the cartridge (30) consists of a circumferential protrusion (39) formed at the proximal end (31a) of the container body (31) and adapted to snap into the outer casing of the drug autoinjector (100).
12. The cartridge (30) according to claim 10 or 11, further comprising a second rubber element (33b), wherein, The support (41) for the needle (40) includes a first cylindrical portion (41a) and a second portion (41b), the second portion being configured to engage with an opening (38b) formed in the second rubber member (33b), and the at least one transverse channel (43) being formed between the first portion (41a) and the second portion (41b) of the support (41) for the needle (40).
13. The cartridge (30) according to any one of claims 10 to 12, wherein, At least one gasket (48; 48a', 48b') is present on the outer surface of the support (41; 41') for the needle (40) to facilitate tight sliding of the support (41; 41') inside the cartridge (30) and prevent leakage of the drug (F), and wherein, on the surface of the closed wall (34) of the distal end (31b) of the container body (31) of the support (41; 41') for the needle (40) facing the cartridge (30), there is a gasket (47; 47') to prevent leakage of the drug (F).
14. The cartridge (30) according to claim 12, wherein, The first rubber component (33a) and the second rubber component (33b) are positioned inside the cartridge (30) so that their corresponding surfaces (36a, 36b) face each other.
15. The cartridge (30) according to any one of claims 10 to 14, wherein, An annular extension (45) extends from the outer surface (34c) of the wall (34) of the distal end (31b) of the container body (31) that encloses the cartridge (30), wherein an air escaping opening (46) is formed in the annular extension (45).