Manufacturing process of hollow plunger rod

Abstract

A method of manufacturing a plunger for a drug delivery device includes forming a plunger body. The method includes loading the plunger body into a cavity of a first mold tool of a molding system. The cavity is at least partially defined by a first mold part and a second mold part. The method includes coupling a second mold tool to the first mold tool to form a plurality of channels defined by grooves in the first and second mold tools, and injecting molten plastic into the plurality of channels to form an overmolded plunger body. The overmolded plunger body includes a head coupled to a first end of the plunger body and a foot coupled to a second end of the plunger body. The foot is at least partially coupled to an inner wall and the head is coupled to an outer wall of the plunger body.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS Priority is claimed to U.S. Provisional Patent Application No. 63 / 158,165, filed March 8, 2021, the entire contents of which are incorporated herein by reference.

[0002] The present disclosure relates to drug delivery devices and, more particularly, to methods of manufacturing drug delivery devices. [Background technology]

[0003] General aversion to exposed needles and health and safety concerns have led to the development of drug delivery devices that hide the needle or other insertion member prior to use and automate various aspects of the injection process. Such devices offer various advantages over traditional forms of drug delivery, including, for example, delivery by a traditional syringe.

[0004] Many injector systems use coil or other spring structures to provide actuation energy for functions such as insertion and / or fluid delivery. The use of springs can offer advantages of simplicity and low cost, but can have certain limitations. For example, there is a linear relationship between force and displacement of the spring actuator. When initiating drug delivery, an excessive amount of energy may be input into the system to provide enough energy for drug delivery at the end of the plunger stroke. As another example, the spring force required may increase when more viscous drugs are delivered by the autoinjector. A spring with a higher spring constant may impart more force to the drug product and primary container. Various physical properties of the spring, such as the spring wire diameter, the spring average diameter, the number of turns of the spring, and the spring material, can affect the spring constant and therefore the spring force. Therefore, it may be desirable and / or advantageous to include device components that allow flexible spring design and / or facilitate the use of springs with different physical properties than the remaining device components.

[0005] The present disclosure describes a drug delivery device that embodies an advantageous alternative to existing drug delivery devices and that may address one or more of the problems or needs set forth herein. Summary of the Invention [Means for solving the problem]

[0006] According to a first exemplary aspect, a method of manufacturing a plunger for a drug delivery device can include inserting a sheet metal blank into an inlet of a stamping machine, the stamping machine including an inlet, an outlet, and a travel path extending between the inlet and the outlet. The method can include operating the stamping machine to advance the sheet metal blank along the travel path of the stamping machine. The travel path can include a plurality of stages configured to process the sheet metal blank into a plurality of plunger bodies. Each of the plunger bodies can include an inner wall defining an axial chamber, an outer wall, a first end, and a second end opposite the first end. The method can include forming a plurality of plunger bodies from the sheet metal blank as the sheet metal blank passes through the travel path and exits from the outlet. The method can include separating each of the plurality of plunger bodies from the sheet metal blank and loading at least one of the plurality of plunger bodies into a cavity of a molding tool of a molding system. Finally, the method can include injecting molten plastic into a plurality of channels of the molding tool to form an overmolded plunger body. The overmolded plunger body can have at least one overmolded portion.

[0007] According to a second exemplary aspect, a method of manufacturing a plunger of a drug delivery device may include forming a plunger body having an inner wall and an outer wall defining an axial chamber, the plunger body including a first end and a second end opposite the first end. The method may include loading the plunger body into a cavity of a first mold tool of a molding system and coupling a second mold tool to the first mold tool to form a plurality of channels defined by grooves in the first and second mold tools. The second mold tool may include a cavity sized to receive a portion of the plunger body when the plunger body is disposed within the cavity of the first mold tool. Finally, the method may include injecting molten plastic into the plurality of channels to form an overmolded plunger body. The overmolded plunger body may include at least one overmolded portion.

[0008] According to a third exemplary aspect, a method of manufacturing a plunger body of a drug delivery device can include inserting a sheet metal blank into an inlet of a stamping machine. The stamping machine can include an inlet, an outlet, and a path of travel extending between the inlet and the outlet. The method can include operating the stamping machine to advance the sheet metal blank along the path of travel of the stamping machine. The path of travel can include a plurality of stages configured to process the sheet metal blank into a plurality of plunger bodies. Each of the plurality of plunger bodies can include an inner wall defining an axial chamber, an outer wall, a first end, and a second end opposite the first end. The method can include forming a plurality of plunger bodies from the sheet metal blank as the sheet metal blank passes along the path of travel and exits the outlet. Finally, the method can include separating each of the plurality of plunger bodies from the sheet metal blank.

[0009] According to a fourth exemplary aspect, a method of manufacturing a plunger body of a drug delivery device can include inserting a sheet metal blank into an inlet of a stamping machine, the stamping machine including an inlet, an outlet, and a path of travel extending between the inlet and the outlet. The method can include operating the stamping machine to advance the sheet metal blank along the path of travel of the stamping machine. The path of travel can include a plurality of stages configured to process a portion of the sheet metal blank into a plurality of plunger bodies. Each of the plurality of plunger bodies can include an inner wall defining an axial chamber, an outer wall, a first end, and a second end opposite the first end. The method can include forming a plurality of plunger bodies from the sheet metal blank as the sheet metal blank advances along the path of travel and exits the outlet, and separating each of the plurality of plunger bodies from the sheet metal blank.

[0010] According to a fifth exemplary embodiment, a method of molding a plunger of a drug delivery device can include loading a plunger body into a cavity of a first mold tool of a molding system. The plunger body can include an inner wall defining an axial chamber, an outer wall, a first end, and a second end opposite the first end. The cavity can at least partially define a first molded portion, an intermediate portion, and a second molded portion. The method can include coupling a second mold tool to the first mold tool to form a plurality of channels defined by grooves in the first and second mold tools. The method can include injecting molten plastic into the plurality of channels of the first and second mold tools and into the first molded portion and the second molded portion to form an overmolded plunger body. The overmolded plunger body can include a head coupled to the outer wall and at least partially surrounding the first end of the plunger body, and a foot coupled to the second end of the plunger body.

[0011] According to a sixth exemplary embodiment, a molding system for forming a portion of a plunger of a drug delivery device can include a first molding tool having a cavity at least partially defined by a first molding portion, a middle portion, and a second molding portion. The second molding tool can have a cavity corresponding to the cavity of the first molding tool and including the first molding portion, the middle portion, and the second molding portion. The first molding tool and the second molding tool can have a plurality of grooves formed therein. The plurality of grooves can be configured to form a plurality of channels when the first molding tool is coupled to the second molding tool. When the first and second molding tools are coupled, the first molding portion of the first molding tool and the second molding portion of the second molding tool can define a head mold for the plunger and the second molding portion of the first molding tool and the second molding tool can define a foot mold for the plunger.

[0012] According to a seventh exemplary embodiment, a stamping machine for forming a plunger body of a drug delivery device component can include a housing defining an inlet, an outlet, and a path of movement extending between the inlet and the outlet. A gripper can be disposed within the housing and configured to engage and advance a sheet metal blank along the path of movement of the housing. A plurality of movable dies can be disposed along the path of movement and configured to impact the sheet metal blank to form a cylindrical plunger body. At least one of the plurality of dies can be disposed above the path of movement and at least one of the plurality of dies can be disposed below the path of movement.

[0013] According to any one or more of the above first to seventh exemplary aspects, the method, molding system, and stamping machine for manufacturing and molding the plunger and plunger body of a drug delivery device may further include any one or more of the following preferred aspects:

[0014] In a preferred form, injecting the molten plastic can include injecting molten plastic to form a head portion coupled to the outer wall and at least partially surrounding the first end of the plunger body, and a foot portion coupled to the second end of the plunger body.

[0015] In a preferred form, loading at least one of the plurality of plunger bodies may include loading the plurality of plunger bodies into a plurality of cavities formed in a mould tool.

[0016] In a preferred form, the method may include bonding the first moulding tool to a second moulding tool prior to injecting the molten plastic into the plurality of channels.

[0017] In a preferred form, the first moulding tool may include a cavity sized to receive the plunger body.

[0018] In a preferred form, the first and second moulding tools are capable of forming a plurality of channels when joined together.

[0019] In a preferred form, injecting the molten plastic into the plurality of channels may include injecting the molten plastic into a second mold tool to distribute the molten plastic among the first mold portion and the second mold portion of the cavity.

[0020] In a preferred form, loading at least one of the plurality of plunger bodies includes coupling a hanger attached to a first end of each plunger body to a pin of a forming tool, and a stamping machine forms the hanger in the sheet metal blank for each of the plurality of plunger bodies.

[0021] In a preferred form, forming the plurality of plunger bodies may include cutting a portion of a sheet metal blank to create a rectangular notch.

[0022] In a preferred form, the rectangular cutout can include a first end, a second end opposite the first end, first and second sides extending between the first and second ends, a first surface, and a second surface opposite the first end.

[0023] In a preferred form, the first end may be attached to a first parallel edge of a sheet metal blank.

[0024] In a preferred form, the second end may be attached to a parallel second edge of the sheet metal blank.

[0025] In a preferred form, forming the plurality of plunger bodies may include molding a rectangular cutout mounted in a sheet metal blank to form a cylindrical shape by stamping at least one of a first surface and a second surface of the rectangular cutout with a contoured die.

[0026] In a preferred form, forming the plurality of plunger bodies may include gradually bending first and second sides of a rectangular cutout inwardly as the sheet metal blank moves in a direction toward an exit of the stamping machine, the first surface of the rectangular cutout defining an inner wall of each of the plurality of plunger bodies.

[0027] In a preferred form, cutting a portion of the sheet metal blank to form a rectangular cutout may include cutting a corrugated edge to form a first end of the rectangular cutout.

[0028] In a preferred form, the method may include bending a scalloped edge at a first end of the rectangular cutout such that the scalloped edge is substantially perpendicular to a first surface of the rectangular cutout.

[0029] In a preferred form, cutting a portion of the sheet metal blank to form a rectangular notch may include cutting a corrugated edge to form a second end of the rectangular notch.

[0030] In a preferred form, the method may include bending the scalloped edge of the second end of the rectangular cut-out so that the scalloped edge is substantially perpendicular to the first surface of the rectangular cut-out.

[0031] In a preferred form, bending the corrugated edge of the second end may include bending the corrugated edge of the second end toward the first surface of the rectangular cutout.

[0032] In a preferred form, separating each of the plurality of plunger bodies may include cutting a portion of the parallel edges of the sheet metal blank to remove the plunger body.

[0033] In a preferred form, a portion of the parallel edges may define a hanger connected to the first end of the plunger body.

[0034] In a preferred form, inserting the sheet metal blank can include inserting a flat sheet of stainless steel having a thickness ranging from about 0.0001 inches to about 0.0003 inches.

[0035] In a preferred form, the method may include cooling the overmolded plunger body to form a hardened plunger.

[0036] In a preferred form, the method may include moving the first mould tool from a first position to a second position prior to coupling the second mould tool to the first mould tool.

[0037] In a preferred form, moving the first form tool may include rotating a moveable table, the first form tool being mounted to a surface of the moveable table.

[0038] In a preferred form, injecting the plurality of channels may include injecting molten plastic into a second mould tool when the first mould tool is in the second position.

[0039] In a preferred form, the method may include inserting a rod into the axial chamber of the plunger body prior to coupling the first mould tool to the second mould tool.

[0040] In a preferred form, injecting the plurality of channels may include injecting curved channels formed in a second mould tool.

[0041] In a preferred form, the curved channel can include a diameter in the range of about 0.1 mm to about 0.2 mm and can be coupled to a second molded portion of the cavity.

[0042] In a preferred form, the cavity may be at least partially defined by the first molded portion, the intermediate portion, and the second molded portion.

[0043] In a preferred form, the method may include removing the hardened plunger from the first mould tool by actuating an ejector pin in the first mould tool.

[0044] In a preferred form, an ejector pin is capable of pushing the hardened plunger out of a cavity formed in the first mold tool.

[0045] In a preferred form, removing the hardened plunger may include automatically cutting a plurality of plastic tubes formed in a plurality of channels connected to the head and foot of the hardened plunger, thereby providing the plunger.

[0046] In a preferred form, loading the plunger body may include loading a first end into a first molded portion of the cavity and loading a second end into a second molded portion of the cavity.

[0047] In a preferred form, injecting the plurality of channels may include injecting molten plastic into first and second mold tools.

[0048] In a preferred form, a plurality of channels may extend between the first and second mould portions of the cavity of the first mould tool, and between the first and second mould portions of the second mould tool.

[0049] In a preferred form, injecting molten plastic into the first and second mold tools can include forming a head having at least one flange extending radially outward from the first end of the plunger body, and forming a cam follower on the at least one flange.

[0050] In a preferred form, loading the plunger body into the cavity may include positioning the plunger body over a vacuum slot formed in a wall of the first mould tool.

[0051] In a preferred form, the vacuum slot may be configured to adhere the plunger body to the forming tool.

[0052] In a preferred form, the method may include activating an alarm when the plunger body is not loaded within the cavity.

[0053] In a preferred form, the vacuum slot may include a sensor communicatively coupled to an alarm and configured to issue an alarm when the sensor detects a condition of the plunger body and cavity.

[0054] In a preferred form, forming the plunger bodies may include stamping a plurality of plunger bodies from a sheet metal blank.

[0055] In a preferred form, stamping the plurality of plunger bodies from a sheet metal blank may include advancing the sheet metal blank in a stamping machine.

[0056] In a preferred form, the sheet metal blank can be moved between a number of stations where the axial chambers of the plunger body are formed.

[0057] In a preferred form, forming the plunger body may include forming a sheet metal blank into a cylindrical shape having a body thickness of less than 0.6 millimeters.

[0058] In a preferred form, forming the plunger body may include cutting a corrugated edge into a sheet metal blank and bending the corrugated edge such that the first end of the plunger body includes a corrugated edge bent outwardly relative to the axial chamber.

[0059] In a preferred form, forming the plunger body may include cutting a corrugated edge into a sheet metal blank and bending the corrugated edge such that the second end of the plunger body includes a corrugated edge bent inwardly relative to the axial chamber.

[0060] In a preferred form, injecting the molten plastic into the plurality of channels may include forming a head adjacent an outer wall of the plunger body and bonding the head to a corrugated edge of the first end of the plunger body.

[0061] In a preferred form, injecting the molten plastic into the plurality of channels may include forming a foot at least partially adjacent an inner wall of the plunger body and bonding the foot to a corrugated edge of the second end of the plunger body.

[0062] In a preferred form, moving the first form tool may include rotating the moveable table at least 180 degrees, the first form tool being mounted to a surface of the moveable table.

[0063] In a preferred form, injecting molten plastic into the plurality of channels may include injecting molten plastic into first and second mould tools.

[0064] In a preferred form, a plurality of channels may extend between the first and second moulding portions of the first moulding tool and between the first and second moulding portions of the second moulding tool.

[0065] In a preferred form, the vacuum component may be located in an intermediate portion of the cavity of the first mould tool.

[0066] In a preferred form, the sensor may be coupled to a vacuum component.

[0067] In a preferred form, the sensor is capable of detecting the absence of an object covering a slot in the vacuum component and signaling the processor to activate an alarm.

[0068] In a preferred form, the curved channel may be formed in a second moulding tool and may be fluidly connected with a second moulding part.

[0069] In a preferred form, the curved channel may have a diameter in the range of about 0.1 mm to about 0.3 mm.

[0070] In a preferred form, the first and second mold portions of the first mold tool may be fluidly coupled by at least one of a plurality of channels.

[0071] In a preferred form, the first mould tool may be moveable relative to the second mould tool between the first station and the second station.

[0072] In a preferred form, a second moulding tool may be located at the second station.

[0073] In a preferred form, the first forming tool is rotatable relative to the second forming tool.

[0074] In a preferred form, the second moulding tool is axially movable relative to the first moulding tool such that the second moulding tool moves towards the first moulding tool when the first moulding tool is positioned at the second station.

[0075] In a preferred form, the system may include a rotatable table, with the first forming tool coupled to the rotatable table.

[0076] In a preferred form, a third forming tool is coupled to a rotatable table and can be spaced from the first forming tool.

[0077] In a preferred form, the third moulding tool may be substantially identical to the first moulding tool.

[0078] In a preferred form, a slidable plate may be coupled to the first moulding tool.

[0079] In a preferred form, the first moulding tool may include a plurality of cavities and the second moulding tool may include a plurality of cavities corresponding to the plurality of cavities of the first moulding tool.

[0080] In a preferred form, the first moulding portion of the first moulding tool may be removably coupled to the first moulding tool.

[0081] In a preferred form, the first moulding portion of the second moulding tool may be removably coupled to the second moulding tool.

[0082] One aspect of the disclosure provides a drug delivery device including a housing defining a longitudinal axis and having an opening, and a drug reservoir including a delivery member having an insertion end configured to extend at least partially through the opening in a delivery state. The device may further include a plunger movable toward a distal end of the drug reservoir to expel the drug from the drug reservoir through the delivery member, the plunger including a plunger body having an inner wall defining an axial chamber and an outer wall cooperating with the inner wall to define a body thickness. The device may also include a plunger biasing member disposed at least partially within the axial chamber and configured to urge the plunger toward the distal end of the drug reservoir.

[0083] The plunger body may have a hollow tubular shape.The plunger body may be metallic or non-metallic.

[0084] The plunger may be configured to selectively rotate from an initial rotational position to a second rotational position under a biasing force exerted by the plunger biasing member, and to translate linearly toward a distal end of the drug storage container after rotating from the initial rotational position to the second rotational position under a biasing force exerted by the plunger biasing member.

[0085] The device may further include a plunger guide fixed relative to the housing, the plunger being at least partially disposed within the plunger guide. One of the plunger and the plunger guide may include a cam and the other of the plunger and the plunger guide may include a cam follower.

[0086] The plunger may include a cam follower, the plunger guide may include a cam, and the cam follower may be formed by at least one flange extending radially outward from the plunger.

[0087] The plunger body thickness may be less than 0.6 millimeters, less than 0.4 millimeters, less than 0.3 millimeters, less than 0.2 millimeters, less than 0.1 millimeters, or less than 0.05 millimeters.

[0088] Another aspect of the present disclosure provides a drug delivery device including a housing defining a longitudinal axis and having an opening, and a drug reservoir including a delivery member having an insertion end configured to extend at least partially through the opening in a delivery state. The device may further include a plunger movable toward a distal end of the drug reservoir to expel the drug from the drug reservoir through the delivery member, the plunger including a body portion having an inner wall defining an axial chamber and an outer wall cooperating with the inner wall to define a body thickness of less than 0.6 millimeters. The device may also include a plunger biasing member coupled to the plunger and configured to urge the plunger toward the distal end of the drug reservoir. [Brief description of the drawings]

[0089] [Figure 1] 1A-1D are perspective views of an exemplary drug delivery device according to various embodiments. [Diagram 2] FIG. 2 is a cross-sectional view of the drug delivery device of FIG. 1. [Figure 3A] FIG. 3 is an exploded view of a portion of the drug delivery device of FIG. 2, namely the drive mechanism. [Figure 3B] FIG. 3 is an exploded view of the drug delivery device of FIG. 2. [Figure 4A] FIG. 2 is a perspective view of a plunger rod manufactured in accordance with the systems and methods disclosed herein. [Figure 4B] FIG. 4B is a front view of the plunger rod of FIG. 4A. [Figure 4C] FIG. 4B is a side view of the plunger rod of FIG. 4A. [Figure 4D] FIG. 4D is a cross-sectional view of the plunger rod of FIG. 4C taken along line DD. [Figure 4E]FIG. 4B is a top view of the plunger rod of FIG. 4A. [Diagram 5] 4B is a schematic diagram of an exemplary method for manufacturing the plunger rod of FIG. 4A in accordance with the systems and methods disclosed herein. [Figure 6] FIG. 1 is a top perspective view of a stamping system for producing a plurality of plunger rod straws, constructed in accordance with the teachings of the present disclosure; [Figure 7] 7 is a schematic side view of a sheet metal blank moving through the stamping system of FIG. 6. [Figure 8] FIG. 7 is a top view of a portion of the stamping system of FIG. 6. [Figure 9A] 7A-7C are perspective views of an exemplary processing stage of the stamping system of FIG. [Figure 9B] 7 is a perspective view of another exemplary processing stage of the stamping system of FIG. 6. [Figure 9C] FIG. 7 is a top view of a completed plunger rod straw and hanger assembled using the stamping system of FIG. [Figure 10] 4B is a schematic diagram of an exemplary method for manufacturing a straw for the plunger rod of FIG. 4A according to the systems and methods disclosed herein. [Figure 11A] 1 is a side view of a blank sheet metal being processed with the stamping system of the present disclosure, showing stages 1-29 of the plunger rod straw during the stamping process. FIG. [Figure 11B] FIG. 11B is an enlarged side view of the processed sheet metal of FIG. 11A showing steps 1-10 of the stamping process. [Figure 11C] FIG. 11B is an enlarged side view of the processed sheet metal of FIG. 11A, showing steps 11-20 of the stamping process. [Figure 11D] FIG. 11B is an enlarged side view of the processed sheet metal of FIG. 11A, showing steps 21-29 of the stamping process. [Figure 12A] 11B is a top view of a blank sheet metal being processed with the stamping system of the present disclosure, corresponding to the side view stage shown in FIG. 11A. FIG. [Figure 12B]FIG. 12B is an enlarged top view of the processed sheet metal of FIG. 12A, corresponding to the side view stage shown in FIG. [Figure 12C] 12B is an enlarged top view of the processed sheet metal of FIG. 12A, corresponding to the side view stage shown in FIG. 11C. [Figure 12D] FIG. 12B is an enlarged top view of the processed sheet metal of FIG. 12A, corresponding to the side view stage shown in FIG. [Figure 13] 11A and 12A, showing the plunger rod straw at various stages of the stamping process. [Figure 14] FIG. 1 is a top perspective view of a plunger rod round table molding system constructed in accordance with the teachings of the present disclosure. [Figure 15] 4B is a schematic diagram of an exemplary method for manufacturing an overmolded part on the straw of the plunger rod of FIG. 4A in accordance with the systems and methods disclosed herein. [Figure 16] FIG. 15 is a top perspective view of a first molding tool positioned at a first station of the plunger rod round table molding system of FIG. [Figure 17] FIG. 2 is a top view of a first mold tool with multiple plunger rod straws loaded into the first mold tool. [Figure 18A] FIG. 2 is a top view of a first cavity of a first mould tool before the first mould tool is loaded. [Figure 18B] FIG. 2 is an enlarged view of a first molding portion of a first molding tool. [Figure 19A] FIG. 13 is a top view of a plunger rod straw positioned within a cavity of a first mold tool. [Figure 19B] FIG. 19B is a top close-up view of the second end of the plunger rod straw positioned in the second molding portion of the first molding tool of FIG. 19A. [Figure 19C] FIG. 19B is a top close-up view of a first end of a plunger rod straw positioned in a first molding portion of a first molding tool of FIG. 19A. [Figure 20]FIG. 13 is a top perspective view of a stop plate for aligning multiple plunger rod straws in a first mold tool. [Figure 21] FIG. 2 is a perspective view of a mating surface of a second mold tool constructed in accordance with the teachings of the present disclosure. [Figure 22] 1 is a cross-sectional view of a mold showing a mating surface of a second mold tool coupled to a mating surface of a first mold tool when the first mold tool is at a second station. [Diagram 23] FIG. 13 is a perspective view of an overmolded plunger body and a first group of channels formed during injection molding of the first and second mold tools. [Figure 24A] FIG. 13 is a perspective view of an overmolded plunger body and a second group of channels formed during injection molding of the first and second mold tools. [Figure 24B] FIG. 24B is a partial enlarged view of the overmolded plunger body and adjacent channel of FIG. 24A. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0090] 1-3 show several views of an embodiment of a drug delivery device 10 for delivering a drug, also referred to herein as a medicament or drug product. The drug may be, but is not limited to, various biological agents such as peptides, peptibodies, or antibodies. The drug may be in a fluid or liquid form, although the present disclosure is not limited to a particular condition.

[0091] Various implementations and configurations of the drug delivery device 10 are possible. This embodiment of the drug delivery device 10 is configured as a single-use, disposable injector. In other embodiments, the drug delivery device 10 may be configured as a multiple-use, reusable injector. The drug delivery device 10 can be operated by a formally trained healthcare provider (e.g., a doctor or nurse) for self-administration by a patient or for a caregiver. The exemplary drug delivery device shown in the figures can take the form of an auto-injector or pen injector and thus can be held in the hand of a user for the duration of drug delivery, but can also or alternatively be suited to other drug delivery devices and / or configurations.

[0092] As shown in FIG. 1, the drug delivery device 10 includes an outer casing or housing 12. The housing 12 may be preloaded with a drug storage container 20, for example by a manufacturer, or alternatively, may be loaded with the drug storage container 20 by a user prior to use of the drug delivery device 10. The drug storage container 20 may include a rigid wall defining an internal bore, i.e., reservoir. The wall may be made of glass or plastic. A stopper 24 may be movably disposed within the drug storage container 20 such that the stopper 24 may move distally along the longitudinal axis A between the proximal and distal ends of the drug storage container 20. The stopper 24 may be made of rubber or any other suitable material. The stopper 24 may slidably and sealingly contact the inner surface 15 of the wall of the drug storage container 20 to prevent or inhibit leakage of the drug 22 past the stopper 24 when the stopper 24 is being moved. Distal movement of the stopper 24 expels the drug 22 from the reservoir of the drug storage container 20 into the delivery member 16. The proximal end of the drug storage container 20 may be open to allow the plunger 26 to extend into the drug storage container 20 and push the stopper 24 distally. In this embodiment, the plunger 26 and the stopper 24 are initially spaced apart by a gap 18 (FIG. 2). Upon actuation of the drive mechanism 30, the plunger 26 moves distally to close the gap and abut the stopper 24. Distal movement of the plunger 26 then drives the stopper 24 distally to expel the drug 22 from the drug storage container 20. In an alternative embodiment, the stopper 24 and the plunger 26 may initially be in contact with each other or may be coupled to each other, for example via a threaded coupling, so that they move together from the start of the movement of the plunger 26. Once the stopper 24 is in the moving state, it can continue to move distally until the stopper contacts a proximally-facing portion of the inner surface 15 of the wall of the drug reservoir 20. This position of the stopper 24 may be referred to as the end-of-dosing or end-of-delivery position and may correspond to when delivery of the drug 22 to the patient is complete or substantially complete.

[0093] In some embodiments, the housing 12 may be sized and dimensioned to allow a person to grip the injector 10 with one hand. The housing 12 may have a generally elongated shape, such as a cylindrical shape, and extend along a longitudinal axis A between a proximal end and a distal end. An opening 14 (FIG. 3B) may be formed at the distal end to allow an insertion end 28 of the delivery member 16 (FIG. 2) to extend outside the housing 12. A transparent or translucent inspection window 17 (FIG. 1A) may be disposed in a wall of the housing 12 to allow a user to view components within the drug delivery device 10, including the drug reservoir 20. A removable cap 19 may cover the opening 14 prior to use of the drug delivery device 10, and in some embodiments may include a gripper 13 (FIG. 2) configured to aid in removal of a sterility barrier 21 (e.g., a rigid needle shield (RNS), a non-rigid needle shield (nRNS), etc.) attached to the insertion end 28 of the delivery member 16.

[0094] As shown in FIG. 2, the drive mechanism 30 may be disposed partially or entirely within the housing 12. In general, the drive mechanism 30 may be configured to store energy and upon or in response to actuation of the drive mechanism 30 by a user, release or output the energy to drive the plunger 26 to expel the drug 22 from the drug reservoir 20 through the delivery member 16 and into the patient. In this embodiment, the drive mechanism 30 is configured to store mechanical potential energy, although alternative embodiments of the drive mechanism 30 may be configured in different forms, for example, such that the drive mechanism 30 stores electrical or chemical potential energy. In general, upon actuation of the drive mechanism 30, the drive mechanism 30 may convert the potential energy into kinetic energy to move the plunger 26. As best shown in FIG. 3A, in one embodiment, the drive mechanism 30 includes a plunger biasing member 50, a hollow rod 46 for supporting the plunger biasing member 50, a plunger biasing member seat 38, a releaser member 52, a plunger guide 60, an extender biasing member 35, and a guard extension 37. The plunger biasing member 50 may include a compression spring (e.g., a helical compression coil spring) that is initially held in a biased state within the bore of the plunger 26. In the biased state, the plunger biasing member 50 may be compressed such that its axial length is shorter than in a natural or unbiased state. When released, the plunger biasing member 50 attempts to expand to its natural axial length, thereby exerting a biasing force that may push the plunger 26 in a distal direction.

[0095] As best shown in Figures 2 and 3B, the housing 12 may include two separate interconnected structures, namely, a rear end cap 23 (e.g., a rear cover) at the proximal end of the drug delivery device 10 and a tubular housing 25 that extends substantially entirely along the length of the drug delivery device 10 and defines the opening 14. Additionally or alternatively, the housing 12 may include fewer or more components, e.g., a two-part tubular housing having a front portion and a rear portion. The tubular housing 25 may have a hollow and generally cylindrical or tubular shape, and the rear end cap 23 may have a generally hemispherical or hollow cylindrical shape with an open end and a closed end. In some embodiments, the rear end cap 23 and the tubular housing 25 and any components disposed therein may be combined to define different subassemblies, such as a drive mechanism 30 (Figure 3A). In some embodiments, different subassemblies are assembled independently of one another and then combined with one another and with the drug reservoir 20 to form the fully assembled drug delivery device 10. In certain such embodiments, some or all of the aforementioned assembly phases may occur in different manufacturing facilities or environments. In another embodiment, the housing 12 may be assembled in one piece such that the housing 12 is defined by a single monolithic structure that integrates the rear cap and the tubular housing into a single component.

[0096] In one embodiment, the container holder 31 fixes and / or anchors the position of the drug storage container 20 within the housing 12. For example, the container holder 31 may be configured to support the drug storage container 20 relative to the housing 12 proximal to at least a portion of the distal end of the body portion of the drug storage container 20 (e.g., including proximal to the entire distal end of the body portion of the drug storage container 20) such that a resultant force acting from the plunger biasing member 50 on the drug storage container 20 is at least substantially fully supported by the distal end of the body portion of the drug storage container 20. The container holder 31 may have a hollow and generally cylindrical or tubular shape centered about the longitudinal axis A, and the drug storage container 20 may be partially or entirely disposed within the container holder 31. The distal end of the container holder 31 may include an inwardly protruding flange 33 that abuts against a shoulder 20a of the drug storage container 20, thereby preventing distal movement of the drug storage container 20 during operation of the plunger 26.

[0097] The term "resultant force" refers to the force that pushes the drug-storage container 20 along the axis A upon and by the actuation of the plunger biasing member 50 during and after an injection condition. For example, when the plunger 26 is actuated and driven distally along the axis A, the plunger 26 pushes the stopper 24 distally. As a result of this direct contact between the plunger 26 and the stopper 24 as well as frictional forces between the stopper 24 and the drug-storage container 20 and the forces required to push the drug 22 through the relatively small diameter delivery member 16, the drug-storage container 20 is pushed distally even though the plunger 26 cannot directly contact, abut, or engage a body portion of the drug-storage container 20. As a result, the drug-storage container 20 may be subjected to a relatively high resultant force during the injection process, and more specifically, during actuation of the plunger 26.

[0098] As best shown in FIGS. 4A-4E, the plunger 26 may have a hollow, generally cylindrical or tubular shape. The plunger 26 may include an annular wall 39 having an outer surface 41 and an inner surface 43. The inner surface 43 may define an interior space 42 (shown in FIG. 4E and also referred to herein as an "axial chamber") sized to receive the plunger biasing member 50. In general, it is desirable to minimize the thickness of the annular wall 39 to the extent possible and without compromising the integrity of the plunger 26 in order to maximize the inner diameter of the plunger 26. This allows a larger diameter plunger biasing member 50 to fit within the interior space of the plunger 26, which in turn allows for a more robust plunger biasing member 50. As a more specific example, the thickness of the annular wall 39 may be less than 2 mm. As another more specific example, the thickness of the annular wall may be less than 1 mm. As another more specific example, the thickness of the annular wall may be less than 0.6 mm. As another more specific example, the thickness of the annular wall may be less than 0.3 mm. As another more specific example, the thickness of the annular wall may be less than 0.2 mm. As another more specific example, the thickness of the annular wall may be less than 0.1 mm. As another more specific example, the thickness of the annular wall may be less than 0.05 mm. The annular wall 39 may be made of any suitable material, such as metal or plastic. To minimize the thickness of the annular wall 39, it may be advantageous to make the annular wall 39 of a metal, such as steel or aluminum. For example, a metal annular wall 39 may have sufficient axial strength and / or buckling resistance for use in a device if the thickness of the annular wall 39 is greater than 0.05 mm. In contrast, a plastic annular wall 39 may have sufficient axial strength and / or buckling resistance for use in a device if the thickness of the annular wall 39 is greater than 1 mm.

[0099] Additionally or alternatively, the hollow rod 46 may facilitate and / or provide greater flexibility in spring design. For example, it may be desirable or advantageous to use devices with different springs depending on the drug properties and / or the desired drug delivery profile. For example, a more viscous drug may require a spring with a higher spring constant and / or spring force, and therefore it may be desirable or advantageous to have flexibility in the physical properties of the spring. As a more specific example, various physical properties of the spring, such as the wire diameter of the spring (generally, as the wire diameter increases, the spring constant increases), the average diameter of the spring (generally, as the average diameter increases, the spring constant decreases), the number of turns of the spring (generally, as the number of turns increases, the spring constant increases), and the material of the spring, may affect the spring constant and therefore the spring force. These physical properties may be adjusted to provide different spring constants, while also, in some cases, adjusting the thickness of hollow rod 46 to maintain a constant or relatively constant outer diameter of the overall plunger 26 and to keep the remaining components of the device constant, such as plunger guide 60 and stopper 24. Additionally or alternatively, hollow rod 46 may promote and / or provide greater longitudinal stability of plunger biasing member 50, such as by preventing or reducing buckling or other transverse movement.

[0100] The plunger biasing member 50 (shown in Figures 2 and 3A) may include the following dimensions: wire diameter 0.65 mm, spring outer diameter 5.40 mm, and number of turns 80-86 (depending on pitch), although other suitable spring characteristics may be used. The plunger biasing member 50 shown in the figures may be formed of stainless steel with a strength of 2300 n / mm, although other suitable materials may be used. The hollow rod 46 shown in the figures may include the following dimensions and materials: length 63 mm, outer diameter 6 mm, wall thickness 0.20 mm, and stainless steel material with a strength of 600-750 n / mm, although other suitable dimensions and materials may be used.

[0101] As described in more detail below, during operation of the drug delivery device 10, the plunger 26 may be configured to selectively rotate relative to the housing 12 and translate linearly relative to the housing 12.

[0102] Returning again to Figures 4A-4E, the plunger 26 may be constructed of multiple interconnected parts or, alternatively, may have a unitary structure. In this embodiment, the plunger 26 is constructed of three separate interconnected structures: a top ring 45 (also referred to herein as the "head" or "head portion") that defines the proximal end of the plunger 26, a base 47 (also referred to herein as the "foot" or "foot portion") that defines the distal end of the plunger 26, and a hollow rod 46 (also referred to herein as the "plunger body") that is located between and rigidly connects the top ring 45 and the base 47. The positions of the top ring 45, hollow rod 46, and base 47 may be fixed relative to one another such that these components do not move relative to one another. The top ring 45, hollow rod 46, and base 47 may each have an annular structure and may be centered about the longitudinal axis A. The top ring 45 and hollow rod 46 may each have a respective central opening 46a that extends through the ends of the components to define the axial chamber 42, while the base 47 may have a central opening that extends through the proximal end of the base 47 but is closed at the distal end of the base 47. The closed end of the base 47 may define a seat or abutment surface for the plunger biasing member 50. In an alternative embodiment, the central opening may extend through the base 47. In such an alternative embodiment, the inner diameter of the central opening of the base 47 may be smaller than the outer diameter of the plunger biasing member 50 such that the base 47 holds the distal end of the plunger biasing member 50 within the plunger 26. The base 47 may be the portion of the plunger 46 that contacts the stopper 24 and urges the stopper 24 distally when the drive mechanism 30 is actuated.

[0103] The top ring 45 at least partially surrounds the proximal or first end 59 of the plunger body 46. The top ring 45 is formed around an outwardly curved scalloped edge 51. As shown in FIG. 4D, the proximal end 63 of the top ring 45 extends above and around the scalloped edge 51 of the proximal end 63 of the plunger body 46. In this manner, the top ring 45 is fixed in place relative to the plunger body 46. The top ring 45 may include one or more flanges or protrusions 48 extending radially outward from a central portion or collar 45A of the top ring 45. Each of the protrusions 48 may include a distally facing cam surface 49. As described in more detail below, the distally facing cam surface 49 may interact with a corresponding cam surface on the plunger guide 60 to release the plunger biasing member 50. The cam surface allows for smoother insertion of the plunger 26 during assembly of the device 10. In some embodiments, distally facing cam surface 49 may be configured at an angle with respect to an imaginary plane perpendicular to longitudinal axis A, or is non-parallel to this imaginary plane.

[0104] The base 47 extends from the distal or second end 61 of the plunger body 46 and is partially disposed within the axial chamber 42 of the plunger body 46. As shown in FIGS. 4C and 4D, the base 47 is formed around the inwardly curved wavy edge 53 of the plunger body 46. The base 47 has a first portion 55 that is disposed within the axial chamber 42 of the plunger body 46 and a second portion 57 that extends away from the distal end of the plunger body 46. The diameter of the first portion 55 may be slightly smaller than the diameter of the second portion 57. However, because the base 47 is formed around the wavy edge 53 of the distal end of the plunger body 46, the base 47 is fixed in place relative to the plunger body 46. The second portion 57 has a distal chamfered portion 47A that acts as a barrier between the metal plunger body 46 and the glass of the syringe. Thus, the plunger 26 does not contact the glass of the syringe as the plunger 26 moves through the medical device 10.

[0105] As described in more detail below, the top ring 45 and / or the base 47 may be constructed of a different material than the hollow rod 46. In some embodiments, the top ring 45 and / or the base 47 may be constructed of plastic, while the hollow rod 46 may be constructed of metal. So constructed, the plastic material used for the top ring 45 may facilitate the camming action described below by providing a relatively low coefficient of friction, and the plastic material used for the base 47 may help absorb or damp any shock or vibration associated with the base 47 striking the stopper 24. The metal material used for the hollow rod 46 may provide sufficient rigidity to avoid buckling under the biasing force exerted by the plunger biasing member 50. In alternative embodiments, the top ring 45, hollow rod 46, and / or base 47 may be made of the same material, including, for example, metal or plastic. In certain such embodiments, the top ring 45, hollow rod 46, and base 47 may be integrally formed in one piece to define a single monolithic structure.

[0106] As discussed above, the plunger biasing member 50 may be at least partially disposed within the plunger 26 and may have a distal end abutting a proximally facing inner surface of the plunger 26 and / or may be fixedly attached to the inner surface of the plunger 26. The outer diameter or other dimension of the plunger biasing member 50 may be equal to or smaller than the inner diameter of the top ring 45 and / or the inner diameter of the hollow rod 46 such that the plunger biasing member 50 may be received within the plunger 26. In some embodiments, the distal end of the plunger biasing member 50 may abut a proximally facing inner surface of the base 47 of the plunger 26. Additionally, as best shown in FIGS. 2 and 3A, the proximal end 50a of the plunger biasing member 50 may abut a distal facing surface 38a of the plunger biasing member seat 38. The plunger biasing member seat 38 may be fixedly attached to the rear housing 27 such that the plunger biasing member seat 38 provides a stationary surface for the plunger biasing member 50 to push against. For example, as shown in FIG. 3A, the plunger seat 38 may include a flange 38b that is received within an opening 60h formed in the proximal portion of the plunger guide, thereby securely coupling the plunger seat to the plunger guide 60. So configured, the plunger biasing member 50, when released from a biased state, may expand in length by moving a distal end of the plunger biasing member 50 in a distal direction away from a stationary proximal end of the plunger biasing member 50. This movement may urge the plunger 26 in a distal direction, which in turn may urge the stopper 24 in a distal direction, expelling the drug 22 from the drug reservoir 20 into the delivery member 16 and thereafter into the patient. However, in the illustrated embodiment, release of the plunger biasing member 50, or any other biasing member, does not drive the delivery member 16 downwardly relative to the housing 12. Instead, the drug product container 20, and thus the delivery member 16, are substantially or completely fixedly coupled to the housing 12. Rather, the delivery member 16 is driven towards the patient's skin 5 by inertial forces generated by a downward force by the patient (or healthcare provider or other person administering the dose).

[0107] As shown in FIG. 2, the releaser member 52 may be disposed radially between the plunger guide 60 and the guard extension 37. The releaser member 52 is also disposed radially between the guard extension 37 and the plunger guide 60. Additionally, the extender bias member 35 may be disposed axially between the releaser member 52 and the guard extension 37 and configured radially around the releaser member 52. Generally, the releaser member 52 is configured to (1) operatively couple the guard member 32 and the plunger 26 in an actuation sequence and (2) generate an audible signal indicating the end of drug delivery. Configured in this manner, the releaser member 52 is used to perform two separate functions, thus reducing the number of moving parts required for the drug delivery device 10.

[0108] As shown in FIG. 3A, the releaser member 52 includes a channel surface 52b that extends proximally beyond a proximal-most (e.g., top) surface of the tubular body of the releaser member 52. For example, the releaser member 52 includes a proximal facing contact surface and a channel surface 52b, each of which extends beyond the contact surface to provide a continuous path for the top ring 45 while also allowing sufficient clearance between the proximal facing contact surface and the corresponding surface involved in end-of-dose signaling. Each of the channel surfaces 52b of the releaser member 52 is configured to receive a protrusion 48 of the top ring 45 and permit axial movement of the plunger 26 relative to the releaser member 52, but inhibit or prevent rotational movement between the plunger 26 and the releaser member 52. As shown in FIG. 3A, the channel surface 52b extends adjacent to the inner surface of the releaser member 52, but the channel surface 52b does not have an arcuate shape, but instead has a generally rectangular bounded shape.

[0109] Some of the device components include various features, surfaces, and openings for interaction with the plunger 26 and for controlling the release movement of the plunger 26 (e.g., the injection sequence). Generally, the injection sequence is initiated by retraction / axial movement of the guard member 32 in a proximal direction (upward in FIG. 2), which causes axial movement of the guard extension 37, unlocking the releaser member 52. Once the releaser member 52 is unlocked (e.g., the first stage of movement), the plunger 26 and plunger biasing member 50 urge the releaser member 52 to rotate clockwise, allowing axial movement of the plunger 26 (distal direction, downward in FIG. 2). The plunger then urges the stopper 24 distally, thereby expelling the drug 22 from the drug product container 20 and from the delivery member 16. When the plunger reaches a particular point along the axial length of the device, travel of the releaser member 52 is further unlocked (e.g., second stage of travel) and the releaser moves proximally (upward in FIG. 2) until it contacts the plunger guide 60, thereby generating an end-of-dose indication (such as an audible click). The injection sequence will now be described in more detail.

[0110] As described in more detail below, during operation of the drug delivery device 10, the plunger 26 may be configured to selectively rotate relative to the housing 12 and translate linearly relative to the housing 12.

[0111] In the pre-delivery state, prior to retraction of the needle guard 32, the plunger 26 and the releaser member 52 may each be configured in a corresponding initial rotational position. The plunger biasing member 50 may be in a biased state. As a result, the plunger biasing member 50 may exert a distally directed biasing force on the plunger 26 that urges the distally facing cam surface 49 of the plunger guide 60 against the proximal facing cam surface. The resulting camming action may cause the plunger 26 to rotate in a clockwise direction. Despite these biasing forces, in the pre-delivery state, neither the releaser member 52 nor the plunger 26 rotate. This is because in the pre-injection state, the releaser member 52 and the plunger are rotatably fixed. Thus, prior to retraction of the guard member 32, as described in more detail herein, the releaser member 52, the plunger guide 60, the guard extension 37, and the housing 12 operate in conjunction with one another to keep the plunger biasing member 50 in the biased state.

[0112] As best seen in FIG. 2, as guard member 32 moves proximally (upward in FIG. 2), the proximal end of guard member 32 contacts the distally facing surface of guard extension 37, urging the guard extension proximally. When the device is in the pre-injection stage, as shown in FIG. 2, the locking flange of guard extension 37 engages the locking flange of releaser member 52, thereby rotationally locking releaser member 52. At this point in the sequence, the distally facing cam surface 49 of top ring 45 of plunger 26 abuts the proximally facing cam surface of plunger guide 60, and this interaction restrains plunger 26 from axial movement. The distally facing cam surface 49 and / or the proximal facing cam surface include an inclined surface to facilitate relative movement of top ring 45 of plunger 26 in a clockwise direction. For example, the distal facing cam surface 49 may have a slope 49a of about 10 degrees, but may have any suitable slope such as 9-11 degrees, 8-12 degrees, 7-13 degrees, 6-14 degrees, 5-15 degrees, 4-16 degrees, or any other suitable slope. Additionally or alternatively, the distal facing cam surface 49 of the top ring 45 may have a slope 49a of about 10 degrees, but may have any suitable slope such as 9-11 degrees, 8-12 degrees, 7-13 degrees, 6-14 degrees, 5-15 degrees, 4-16 degrees, or any other suitable slope. The slope or slopes of each surface 49 create a transverse force to the axial force by the plunger biasing member 50, thereby urging the top ring 45 of the plunger 26 in a clockwise direction. However, as discussed above, while the top ring 45 is disposed within and / or in contact with channel surface 52b, the releaser member 52 blocks or prevents rotational movement between the releaser member 52 and the plunger. As a result, as long as the guard extension 37 rotationally locks the releaser member 52 (as shown in FIG. 2), the top ring 45 remains rotationally locked by channel surface 52b and axially locked by the proximal facing cam surface of the plunger guide 60.

[0113] The unlocking phase of the injection sequence is when the guard extension 37 translates proximally until the locking flanges of the guard extension 37 no longer engage the locking flanges of the releaser member 52 and the releaser is no longer rotationally locked. During this phase, two things happen simultaneously, or nearly simultaneously: (1) the guard bias member 35 urges the releaser member 52 clockwise and upward due to camming surfaces on one or both of the inner surface of the releaser member 52 or the outer surface of the plunger guide 60 which converts the axial force from the guard bias member 35 into a lateral (clockwise) force causing the releaser member 52 to rotate clockwise and move upward (proximally), and (2) the plunger bias member 50 urges the top ring 45 clockwise and downward (distally) due to the camming action between the surface of the plunger 26 and the plunger guide 60, thereby moving the plunger 26 clockwise and slightly downward along the angled surface of the plunger guide 60. In other words, both the releaser member 52 and the top ring 45 of the plunger 26 rotate clockwise at the same time or substantially at the same time due to the forces from the respective biasing members 35, 50. This sliding motion between the surface of the plunger 26 and the plunger guide 60 results in rotation and linear translation (similar to a helical path). Thus, the plunger guide 60 may function as a cam and the plunger rod 26 may function as a cam follower.

[0114] During the downstroke phase, the top ring 45 still appears near the proximal portion of the plunger guide 60, but moves rapidly along the longitudinal slot 86 (FIG. 3A) formed in the plunger guide 60 and the channel surface 52b of the releaser member 52. During this phase, the top ring 45 of the plunger 26 moves along both the channel surface 52b of the releaser member 52 and the longitudinal slot 86 of the plunger guide 60, thereby preventing rotation between any of the three components (26, 52, 60). As a more specific example, the plunger guide 60 is rotatably mounted relative to the housing 12, while the releaser member 52 cannot rotate because the top ring 45 is disposed both within the channel surface 52b and within the longitudinal slot 86. Also, during this phase, as the plunger 26 moves distally, the gap 18 (FIG. 2) between the base 47 of the plunger 26 and the stopper 24 becomes smaller, and the base 47 contacts the stopper 24. The device 10 is designed such that the plunger 26 moves with sufficient force to drive the stopper 24 distally and push the drug 22 out of the delivery member 16. At the same time, the device 10 is also designed to reduce or eliminate the possibility of, for example, glass breakage, undesirable forces acting on the patient, and / or undesirable shock vibrations or sounds due to interactions between the base 47 and the stopper 24. For example, the design parameters of the plunger biasing member 50 may be designed to meet these two sets of design goals. As another example, a damping component may be disposed between the base 47 and the stopper 24 or elsewhere within the device 10 to dampen the forces between the base 47 and the stopper 24. For example, the base 47 may include an elastomeric component, portion, or other damping feature. Additionally or alternatively, the stopper 24 may be formed of an elastomeric material that includes inherent damping properties. Additionally or alternatively, the stopper 24 may include additional elastomeric components, portions, or other damping features.

[0115] In some embodiments, the camming action between the distally facing camming surface 49 on the projection 48 and the proximal facing camming surface of the plunger guide 60 may provide a damping effect. More specifically, the sliding friction between these two surfaces may be selected to slow the initial expansion of the plunger biasing member 50. As a result, during the initial expansion of the plunger biasing member 50, the velocity of the plunger 26 may be reduced compared to free, unhindered expansion of the plunger biasing member 50. The reduced velocity of the plunger 26 may allow the plunger 26 to impact the stopper 24 with less force, thereby reducing the potential for structural damage to the medication reservoir 20 and / or facilitating a more comfortable injection for the user.

[0116] As described above, during the downward stroke phase, the releaser member 52 cannot rotate relative to the plunger guide 60 while the top ring 45 is disposed within the channel surface 52b and the longitudinal slot 86. However, during the end-of-dose initiation phase, the top ring 45, in some embodiments, can release the distal end of the releaser member 52 and no longer restricts or prevents rotation of the releaser member 52. As a more specific example, as the top ring 45 exits the channel surface 52b and / or the distal surface of the releaser member 52, the releaser member 52 is no longer rotationally constrained by the top ring 45 and the releaser member 52 is urged upward by the guard bias member 35. The upward force of the guard bias member 35 and the cam surface causes the releaser member 52 to rotate clockwise while moving upward in a helical path until the proximal facing surface of the releaser member 52 contacts the distal facing surface of the plunger guide 60, thereby producing an audible click. The channel surface 52b and the length of the plunger 26 can be designed so that the top ring 45 exits the channel surface 52b when the stopper 24 reaches a desired point of travel within the drug storage container 20, such as the end of its travel near the distal end of the drug storage container 20.

[0117] A method 100 for manufacturing the plunger 26 of the device 10 shown in Figures 1-4E is shown in Figure 5 and will be described in accordance with the teachings of the present disclosure. The method 100 for manufacturing the plunger can be described in two main phases: a stamping phase (steps 102, 104) in which a stamping machine forms and shapes the plunger body (Figures 6-13) from a blank of sheet metal, and a molding phase (steps 106, 108) in which an injection molding system molds the head and foot 45, 47 onto the plunger body 46 (Figures 14-24B) of the plunger 26. The plunger 26 of Figures 4A-4E is manufactured according to the two phases described below. However, the plunger 26 may be manufactured using a different method incorporating one or both phases.

[0118] Generally, the first phase of the method 100 for manufacturing the plunger 26 of Figures 4A-4E involves forming a plunger body from a sheet metal blank. Initially, a first step 102 involves inserting the sheet metal blank into a stamping machine, followed by step 104, which involves forming a plurality of plunger bodies from the sheet metal. A plurality of stamping dies in the stamping machine progressively form the sheet metal blank (or "workpiece" in place) into a cylindrical shape in a series of stages. The cylindrical workpiece, with the completed plunger body, exits the stamping machine and is either separated from the sheet metal or pre-separated by the stamping machine. In step 106, an operator or robot loads a plurality of plunger bodies into an injection molding system. In step 108, the molding system injects molten plastic into first and second molds to overmold the plunger bodies to form the head 45 and foot 47 components on each plunger body. The overmolded plunger body is cooled and finished before being removed from the molding system and assembled with a drug delivery device, such as device 10 of FIGS. 1-3B. As used herein, the term "sheet metal blank" or "sheet metal" refers to a length of metal that is used in a stamping machine to form a plunger body. The term may refer to the metal before, during, or after it is inserted into the stamping machine and shaped. Thus, the sheet metal blank may have a variety of features, including multiple workpieces at various stages of the stamping process, perforations to facilitate advancement through the machine, and / or bends, dimples, corrugations, embossing, etching, etc.

[0119] 6 and 7, an exemplary stamping machine 110 used to complete a first phase of the manufacturing process 100 is shown constructed in accordance with the teachings of the present disclosure. The stamping machine 110 includes a housing 112, which is partially hidden in FIG. 6 to show the internal components of the stamping machine 110. The machine 110 includes an entrance 114, an exit 116, and a travel path 118 extending between the entrance 114 and the exit 116. According to step 102 of the method 100, an operator (or robot) inserts a blank of sheet metal 120 into the entrance 114 of the machine 110 and transports the sheet metal 120 along the travel path 118. As the sheet metal 120 moves through the machine 110, a number of stamping tools or dies perform step 104, impacting a central portion or workpiece of the sheet metal 120 to form the metal into a plunger body. Prior to exiting through the exit 116 of the machine 110, the sheet metal 120 comprises a workpiece having a cylindrical plunger body. After separation of the workpiece from the sheet metal 120, which the machine 310 may perform before the sheet metal exits the machine 310, and finishing of the workpiece (i.e., cleaning, smoothing, etc.), the final product is a plunger body having an inner wall, an outer wall, and first and second ends defining an axial chamber. As described further below, the plunger body includes a hanger for mounting the plunger body to a forming system and a corrugated edge for enhancing attachment of the formed portion to the metal plunger body. The machine 110 used in the exemplary method 100 of FIG. 5 is a mechanical stamping press, but may also be a hydraulic, mechanical servo, or other type of stamping press.

[0120] FIG. 7 shows a schematic diagram of the stamping machine 110 to more clearly illustrate how the stamping machine 110 processes a blank of sheet metal 120 into a plurality of plunger bodies. Initially, a leading edge 122 of the sheet metal 120 is inserted into the stamping machine 110 at an entrance 114 and processed by a plurality of dies 124 while the sheet metal 120 moves along a path of travel 118. Grippers 126 disposed within a housing 112 of the machine 110 transport the sheet metal 120 along the path of travel 118. In particular, a first gripper 126 located proximal to the entrance 114 contacts first and second parallel edges or margins 128, 130 (FIG. 6) of the sheet metal 120. The gripper 126 includes first and second wheels 132, 134 disposed to engage opposing surfaces of the sheet metal 120. In the illustrated example, the second set of grippers 140 is positioned proximal to the exit 116 of the machine 110 to engage the sheet metal 120 to transport the sheet metal 120 through the machine 110. However, in other examples, the machine 110 may include one gripper mechanism anywhere in the path of travel 118 to transport the sheet metal 120 through the machine 110.

[0121] Specifically, in FIG. 7, a first wheel 132 disposed above the sheet metal 120 engages a first side or surface 136 of the sheet metal 120, and a second wheel 134 disposed below the sheet metal 120 engages a second side or surface 138 of the sheet metal 120. The first wheel 132 rotates in a first direction B, and the second wheel 134 rotates in a second direction C opposite the first direction B, thereby gripping the sheet metal 120 between the rotating wheels 132, 134 and moving the sheet metal 120 in a linear direction D. In the example shown in FIG. 7, each wheel 132, 134 is semicircular, thereby allowing for incremental movement of the blank of the sheet metal 120 as the wheels 132, 134 continuously rotate. However, in another example, the wheels 132, 134 may have a complete circular cross-section such that each portion of the wheel is always engaged with the sheet metal 120. In this case, the wheels 132, 134 may be powered to rotate incrementally rather than continuously. The set of rotating wheels 132, 134 engages one of the margins or parallel edges of the blank of the sheet metal 120 to avoid any interference with the multiple dies and / or the forming of the sheet metal 120 as it moves along the travel path 118. However, as shown in FIG. 6, each of the first and second sets of grippers 126A, 126B are adjacent one of the parallel margins 128, 130 of the sheet metal 120. In yet another example, the grippers may be an entirely different mechanism for transporting the sheet metal 120 through the machine 110.

[0122] 7 generally illustrates an exemplary layout of the multiple dies 124 of the stamping machine 110. The multiple dies 124 move relative to the blank of the sheet metal 120 and are adjacent to the path of travel 118 of the sheet metal 120. The machine 110 operates the multiple dies 124 to impact the sheet metal 120 at various stages of the machine 110 to gradually form a cylindrical workpiece 125 to form a final cylindrical plunger body. At least one of the multiple dies 124 is located above the path of travel 118 and at least one of the multiple dies 124 is located below the path of travel 118. Each of the dies 124 is shaped and positioned relative to the path of travel 118 to form a particular bend, shape, or cut in the workpiece 125 as the one or more dies 124 impact and engage the sheet metal 120. The machine 110 actuates the dies 124 to move towards the sheet metal 120 and contact first and second surfaces 136, 138 of the sheet metal 120 while the sheet metal 120 is stationary relative to the path of travel 118. In several stages, multiple dies 124 are above and below the path of travel 118 to form both sides 136, 138 of the workpiece 125. After the die or dies 124 contact and form the workpiece 125 in each stage, the die or dies 124 in each stage return to their previous position spaced apart from the sheet metal 120. While or shortly after the die or dies 124 disengage from the sheet metal 120, the sheet metal 120 continues to move incrementally in direction D (i.e., as the semicircular wheels 132, 134 of the gripper 126 re-engage the sheet metal 120). This process is continuously repeated, and as the sheet metal 120 stops in the path of travel 118, the dies 124 again move toward the sheet metal 120 to engage and form each workpiece 125 before the sheet metal 120 continues along the path of travel 118. In some stages, also referred to herein as "free" stages, the workpiece 125 may not be shaped or otherwise engaged by any of the movable dies 124. The dies 124 of the stamping machine 110 may include combination dies, compound dies, progressive dies, or transfer dies.

[0123] 8 shows a sheet metal 120 disposed in a travel path 118 of a machine 110 with multiple workpieces 125, each at a different stage of formation. Adjacent to the entrance 114, the sheet metal 120 blank is flat, and adjacent to the exit 116, the sheet metal 120 blank has a rectangular space 142 in which a formed plunger body is formed and separated from the sheet metal 120. In one exemplary stage 9A, a first die 144 and a second die 148 engage both the first and second surfaces 128, 130 of the sheet metal 120 to bend the workpiece 125 inwardly (relative to the first surface 136) to form a cylindrical body 225.

[0124] In the exemplary stage shown in FIG. 9A, the first die 144 has a concave surface 150 and engages the second surface (or bottom surface) 138 of the workpiece 125. At the same time, the second die 148 has a convex surface 152 and engages the first surface (or top surface) 136 of the workpiece 125. As both dies 144, 148 impact the sheet metal 120, the workpiece 125 bends into a curve following the contours of the dies 144, 148. In another stage shown in FIG. 9B, the cylindrical body 225 of the workpiece 125 is nearly completely formed, and at this stage of the forming process, only one die 154 engages the second surface 138, which is formed into the outer wall 160 of the plunger body workpiece 125. Finally, FIG. 9C shows the finished shape of the plunger body 162 in one of the final stages 9C of the stamping machine 110. The plunger body 162 includes a first end 164, a second end 166 opposite the first end 164, an inner wall defining an axial chamber 168, and an outer wall 160. The hanger 170 includes two openings 172 and is connected to the first end 164 of the plunger body 162. The first end 164 includes a scalloped edge 174 that is bent outwardly relative to the axial chamber 168, and the second end 166 includes a scalloped edge 176 that is bent inwardly relative to the axial chamber 168.

[0125] FIG. 10 illustrates a method 200 of forming the plunger body 162 in more detail with reference to FIGS. 11A-12D. As previously mentioned, the method 200 of forming the plunger body 162 begins in step 202 by inserting a blank of the sheet metal 120 into the inlet 114 of the stamping machine 110. In a second step 204, the machine 110 is actuated or turned on, thereby operating one or more grippers 126 of the machine 110 to transport the sheet metal 120 along a path of travel 118. A movable die 124 is positioned along the path of travel 118 and corresponds to a number of stages of processing the central portion of the sheet metal 120 (i.e., the workpiece 125) into the plunger body 162. In one of the first stages of the forming process, a step 206 of cutting out a portion of the sheet metal 120 is performed by one or more of the multiple dies 124. As described in more detail below, step 204 of cutting (also referred to herein as "punching") sheet metal 120 includes cutting one or more portions from sheet metal 120 to form rectangular cutouts. In a subsequent stage of the forming process, die 124 forms the rectangular cutouts by performing step 208 of method 200. Die 124 gradually forms the multiple rectangular cutouts (or workpiece 125) in sheet metal 120 into multiple cylindrical plunger bodies 162. In a final step 210, workpiece 125 is separated from the sheet metal 120 blank.

[0126] 11A and 12A, steps 206, 208 of cutting and shaping a sheet metal 120 blank are shown in stages 1 through 29 of a stamping process 200 (i.e., a method of forming a plunger body). Each of a number of exemplary stages of the method 200 is labeled next to a corresponding workpiece 125 or portion of the sheet metal 120 processed at that stage (i.e., indicating the resulting particular die punch or bend). A single continuously processed sheet metal 120 blank includes a number of different workpieces 125, each of which is processed by the stamping machine 110 at each stage (e.g., punching, blanking, embossing, coining, bending, flanging, etc.). In this way, the stamping machine 110 can process 29 different workpieces 125 at any one time. In other words, the number of stages of the method 200 generally corresponds to the number of workpieces 125 being processed. The next 29 steps of the stamping method 200 are described in three sections of the machine 110. Steps 1-10 are described and illustrated with reference to Figures 11B and 12B. Steps 11-20 are described and illustrated with reference to Figures 11C and 12C. Steps 21-29 are described and illustrated with reference to Figures 11D and 12D. The exemplary steps 1-29 may be modified to arrive at a formed plunger body 162 by increasing or decreasing the number of steps of the machine 110. More or less than 29 workpieces 125 may be simultaneously machined by the machine 110 depending on the desired size and shape of the resulting plunger.

[0127] 11B and 12B show a first stage of forming a blank of sheet metal 120. In stage 1, the sheet metal 120 is initially flat when an operator inserts the sheet metal 120 into the stamping machine 110 and operates the machine 110 to transport the sheet metal 120 along the travel path 118. The machine 110 is programmed to operate step 206 of the method 200 of FIG. 10 in stages 2 through 5. Specifically, in stages 2 and 5, one or more dies 124 punch first and second portions of the sheet metal 120 to define a rectangular cutout 220. In stage 2, a punching die 124 engages a workpiece 125 by punching a right segment 222 of the flat sheet metal 120, and in stage 5, a different punching die 124 engages the workpiece 125 by punching a left segment 224. Once the first and second portions 222, 224 are removed from the workpiece 125, a rectangular cutout 220 is defined and includes a first end 226, a second end 228 opposite the first end 226, a first side 230, and a second side 232 connecting the first end 226 and the second end 228 (as shown in step 5). During these steps, the same or a different punch die 124 forms the first and second scalloped edges 234, 236 of the rectangular cutout 220.

[0128] The one or more dies 124 of the stamping machine 110 further form the wavy edges 234, 236 of the rectangular cutout 220 in steps 6-10. For example, in step 7, the method 200 includes bending the second end 228 of the rectangular cutout 220 toward the first surface 136 of the rectangular cutout 220 such that the second wavy edge 236 is substantially perpendicular to the first surface 136 of the workpiece 125. Similarly, in step 9, the method 200 includes bending the first end 226 of the rectangular cutout 220 toward the second surface 138 of the workpiece 125 such that the first wavy edge 234 is substantially perpendicular to the second surface 138 of the workpiece 125. The steps of bending the wavy edges 234, 236 are shown in steps 7 and 9 of FIG. 11B. Thus, as the cylindrical body 225 of the workpiece 125 takes shape, the wavy ends 234, 236 of the rectangular cutout 220 define the wavy edges 174, 176 of the final plunger body 162 (FIG. 9C). Stages 4, 6, 8, and 10 are considered "free" stages that allow for modifications to the method 200 and machine 110.

[0129] In step 3, the stamping die 124 punches out the workpiece 125 to define a straw foot 242 that connects the second end 228 to the second margin 130 of the blank of the sheet metal 120 (step 5). Opposite the straw foot 242 is a connector 244 that joins the first end 226 of the rectangular cutout 220 to the first margin 128. The straw foot 242 and connector 244 keep the workpiece 125 securely positioned relative to the path of travel 118 as it moves through the stamping machine 110. Later in the method 200, the stamping die 124 cuts and bends the straw foot 242 away from the workpiece 125 and punches out a portion of the first margin 128 to define a hanger 170 for the plunger body 162. The right and left cutouts 222 , 224 also define a first set of tabs 238 and a second set of tabs 240 on each workpiece 125 .

[0130] 11C and 12C show the workpiece 125 being formed into a cylindrical shape. Step 208 of the method 200 is mostly performed in stages 11-20. Forming the rectangular cutouts 220 includes gradually bending the first and second sides 230, 232 of the workpiece 125 inward (i.e., toward the first surface 136) as the blank of the sheet metal 120 moves in a direction D toward the exit 116 of the stamping machine 110, such that the first surface 136 gradually defines what will become the inner wall of the plunger body 162. In other words, the die 124 engages the workpiece 125 to bend the first and second sides 230, 232 of the rectangular cutouts 220 toward each other. For example, in FIG. 11C, the first and second sides 230, 232 of each cutout 220 are bent inwardly relative to the axis E of the workpiece 125. In stages 11, 13, 14, 16, 17, 18, and 20, the machine 110 further shapes the workpiece 125 into a cylindrical body 225 by bending the first and second sides 230, 232 closer together. For example, the first and second sides 230, 232 are spaced apart by approximately 16.5 mm in stage 11, approximately 11.4 mm in stage 13, approximately 6.8 mm in stage 14, approximately 5.4 mm in stage 16, and approximately 2.1 mm in stage 18.

[0131] In the illustrated example, the machine 110 utilizes a progressive tooling method with built-in bending and punching dies for high speed stamping to process two workpieces per second. At each of these punching, bending, and forming stages, the die 124 can shape the sheet metal 120 in one or more of a variety of ways. For example, in some stages, the die 124 stamps the sheet metal 120, plastically deforming the sheet metal 120 to assume the geometric shape of the die. At some stages, the die 124 allows the workpiece 125 to bounce back after impact, while at other stages, the sheet metal 120 is formed such that the workpiece 125 is shaped without allowing the sheet metal 120 to bounce back (i.e., forming beyond the yield stress of the sheet metal 120). Other stamping methods include transfer die stamping, four-slide stamping, fine blanking, etc.

[0132] Finally, in step 20, the cylindrical body 225 of the workpiece 125 is final machined to further close the gap between the two sides 230, 232 of the cutout 220. In the illustrated example, the first and second sides 230, 232 of the workpiece 125 do not touch or overlap. Rather, a seam or longitudinal gap 246 extends from the first and second ends 226, 228 of each workpiece 125. This gap between the first and second sides 230, 232 has a width of less than about 0.05 mm.

[0133] 11D and 12D, the final steps of the stamping method 200 are shown. In steps 22 and 24, the system 110 calibrates the cylindrical body 225 of the workpiece 125. During calibration, a die 124 having the same diameter as the die 124 used during the final bending step (i.e., step 20) engages the second surface 138 of the workpiece 125, which defines the outer wall 160 of the plunger body 162. In step 23, the first and second sets of tabs 238, 240 connected to the first and second margins 128, 130, respectively, are bent minimally to increase stiffness. In step 25, the first and second sets of tabs 238, 240 are bent so that each tab 238, 240 is perpendicular to the first and second margins 128, 130 of the sheet metal 120 blank. These tabs 238, 240 can function to protect the workpieces 125 that remain attached to the sheet metal 120 as the sheet metal 120 is rolled for storage. Although the illustrated workpieces 125 are blanked (i.e., separated) from the sheet metal 120 in steps 27 and 28, in some examples, the stamping machine 110 may be programmed such that the workpieces 125 remain connected to the sheet metal 120. The workpieces 125 attached to the first margin 128 of the sheet metal 120 can be stored by rolling or folding the sheet metal 120. First and second sets of tabs 238, 240 extend from each workpiece to maintain spacing between the workpieces 125 and protect the workpieces 120 during storage.

[0134] Finally, step 210 of separating the workpiece plunger body 162 from the blank of sheet metal 120 is performed in stages 27 and 28. First, in stage 27, one or more dies 124 of the machine 110 cut and bend the straw foot 242 away from the second end 228 of the workpiece 125, leaving the workpiece 125 attached to the sheet metal 120 at the first margin 128. Then, in stage 28, the workpiece 125 is completely removed from the sheet metal 120 by punching out the first margin 128, thereby forming the hanger 170 of the plunger body 162. Stages 21 and 26 are free stages.

[0135] 13 illustrates a blank of sheet metal 120 processed by a stamping machine 110 in accordance with the present disclosure. As shown in this figure, the sheet metal 120 includes multiple workpieces that are being processed at different stages of a method 200 to form the plunger body 162 of FIG. 9C. In this manner, the stamping machine 110 allows for the sheet metal 120 to be continuously processed into workpieces 125, ultimately forming multiple plunger bodies 162. Except for the need to load and / or reload the stamping machine 110 with the sheet metal 120, the method 200 of forming multiple plunger bodies using the stamping machine 110 is a continuous or semi-continuous process.

[0136] 14, an exemplary molding system 300 for performing the second phase of the manufacturing process 100 is configured in accordance with the teachings of the present disclosure. In operation, the molding system 300 forms the head 45 and foot 47 portions of the plunger 26 (FIG. 4A) around a plunger body 162, such as the plunger body 162 formed by the stamping machine 110 of FIGS. 6-9. In general, the molding system 300 includes a first station, Station I, for loading the plunger body 162 and ejecting the overmolded plunger body, and a second station, Station II, for injection molding the head portion 45 and foot portion 47 onto the plunger body 162. At Station I, an operator loads a first molding tool 304 with one or more plunger bodies 162. At station II, the first mold tool 304 is mated to a second mold tool (located directly above an identical first mold tool 306, but hidden in FIG. 14) and the system 300 injects molten plastic into the mold (i.e., the clamped first and second mold tools). When the first and second mold tools are mated at station II, the first and second mold tools define a head mold or negative head space, which defines the head and foot 45, 47 portions of the plunger 26, and a foot mold or negative foot space. The molten plastic is injected through a series of channels in the mold to fill the head and foot molds. Although the system 300 includes two identical first mold tools 304, 306, in other examples, the system 300 may include one first mold tool 304, or more than two first and / or second mold tools.

[0137] FIG. 15 illustrates an exemplary method 310 of overmolding one or more plunger bodies 162 in accordance with the teachings of the present disclosure. A first step 312 includes loading one or more plunger bodies 162 into a first mold tool 304 of a molding system 300. The molding system 300 of FIG. 14 can automatically perform one or more of the following steps of the method 310 after an operator or robot performs step 312. Step 314 of the method 310 includes coupling the first mold tool 304, 306 to a second mold tool. Once the first and second mold tools are coupled, the system 300 injects molten plastic into the first and second mold tools in step 316 to form molded components (i.e., head and foot) on the plunger body 162. Finally, in step 318, the molded component is cooled on the plunger body 162 and the molded plunger body is ejected or otherwise removed from the first mold tool 304, 306 at station I. As a result of the completion of each step of the method, a plurality of plungers for the drug delivery device 10 of Figures 1-3B are provided.

[0138] Returning to FIG. 14, the molding system 300 includes a rotatable table 308 with a first molding tool 304 at station I and another identical first molding tool 306 at station II. Although not shown in FIG. 14, a second molding tool 404 (FIG. 21) is located at station II and is configured to couple to either of the first molding tools 304, 306 to overmold the plunger body 162. Thus, the second molding tool remains at station II while the first molding tools 304, 306 spin in and out of stations I and II. The first molding tool 304 rotates relative to the second molding tool 404, and the second molding tool 404 moves axially relative to the first molding tool 304 to couple to the first molding tool 304 at station II.

[0139] During operation, the table 308 rotates in a direction G to move the first molding tool 304 loaded with one or more plunger bodies 162 from station I to station II. At the same time, the table 308 also moves the other first molding tool 306 from station II to station I. At station II, the plunger body 162 is overmolded by injection molding. After the plunger body 162 of the first molding tool 304 is molded and cooled at station II, the table 308 again rotates the first molding tool 304 back to station I, where the overmolded plunger body is removed from the first molding tool 304 and replaced with an additional plunger body 162. Of course, every time the table 308 rotates to position the first molding tool 304, the other first molding tool 306 rotates to the opposite station. For example, an operator loads a first mold tool 304 at station I, and a plunger body 162 located in the same mold tool 306 is overmolded at station II. The table 308 rotates 180 degrees to move each of the first mold tools 304, 306 between stations I and II. However, other configurations of the molding system 300 are possible and may include additional first mold tools located around the table 308. In yet another example, the molding system 300 may include a linear assembly line or just one station where the loading, injection molding, and ejection steps are performed. Although the exemplary system 300 is designed to overmold multiple plunger bodies, another exemplary system may overmold only one plunger body at a time.

[0140] The first mold tool 304 is generally shown in FIG. 16 and includes a plurality of cavities 320A-D, an actuation plate 322, and an actuation core 324 all coupled to an upper platform 330. The upper platform 330 of the first mold tool 304 also includes a plurality of cooling holes 326 configured to receive a heating fluid for warming the mold tool and a cooling fluid for hardening the molded portion of the overmolded plunger body. As will be described in more detail below, the upper platform 330 is configured to matingly mate with a corresponding platform 430 of the second mold tool 404 (FIG. 22). Various mating surfaces of the upper platform 330 and the corresponding platform 430 of the second mold tool 404 are precision shaped to achieve a tight clamp when the mold tools 304, 404 are mated.

[0141] 17, the first mold tool 304 of the molding system 300 is at station I with four plunger bodies 162 loaded into four separate cavities 320A, 320B, 320C, 320D. The second mold tool 404 has the same number of cavities as the first mold tool 304, with each cavity of the second mold tool formed to cover a plunger body 162 of the first mold tool 304. Each of the cavities 320A-D is defined by a first mold portion 332A-D of the first mold portion plate 332, a middle portion 334A-D of the platform 330, and a second mold portion 336A-D of the second mold portion plate 336. Specifically, the first mold part plate 332 of FIG. 17 defines four separate halves of head molds 332A-D, and the second mold part plate 336 defines four separate halves of foot molds 336A-D. The cavities 320A-D of the first mold tool 304 are connected by a network of grooves 340 formed in the upper platform 330 and the first and second mold part plates 332, 336 of the first mold tool 304. Similarly, the cavities of the second mold tool 404 are also connected to corresponding grooves such that the multiple grooves of both the first and second mold tools 304, 404 are configured to form multiple channels through which molten plastic is injected. When the first mold tool 304 is aligned and mated with the second mold tool 404 at station II, the mold forms multiple channels. As described in further detail below, a plurality of channels extend between the first mold portions 332A-D and the second mold portions 336A-D of each cavity 320A-D of the first mold tool 304, and between the first mold portions and the second mold portions of each cavity of the second mold tool 404.

[0142] The first and second molded part plates 332, 336 are removably coupled to the platform 330 of the first mold tool 304. The first and second molded part plates 332, 336 are interchangeable to modify the molding system 300, and thus the manufacturing method 100, to achieve different resulting plungers. For example, the system 300 can be used to overmold plunger bodies of different dimensions and / or form different molded components on the plunger bodies by simply switching between the molded part plates 332, 336. The molded part plates 332, 336 are sized to fit within cavities formed in the top platform 330 of the first mold tool. Each plate 332, 336 is configured to seamlessly fit into the first mold tool 304 and connect with existing grooves formed in the platform 330 without requiring further adjustment of the system 300 or the mold tool 304. Similarly, the second mold tool 404 (FIG. 21) includes interchangeable first and second mold portions that correspond to the first and second mold portions 332, 336 of the first mold tool 304. Thus, when the first and second mold portions 332, 336 are interchanged within the first mold tool 304, the mold portions of the second mold tool are also interchanged to fit the first mold tool 304. However, in other examples, the cavities 320A-D may be formed completely or partially within the platform 330 and / or the removable plate.

[0143] In FIG. 18A, the first cavity 320A of the first mold tool 304 is more clearly shown. However, it will be understood that the first cavity 320A is substantially similar to the other cavities 302B-D, and as a result, the details of the first cavity 320A described below apply to the other cavities 320B-D as well. The step 312 of loading the first mold tool 304 includes placing the plunger body 162 in the first cavity 320A of the first mold tool 304. In particular, the first end 164 of the plunger body 162 is placed in the first mold portion 332A and the second end 166 of the plunger body 162 is placed in the second mold portion 336A. The cylindrical plunger body 162 rests in the middle portion 334A of the cavity 320A and on one or more vacuum slots 342 formed in the platform 330. The molding system 300 includes a vacuum mechanism coupled to a vacuum slot 342 of each first molding tool 304, 306 to ensure that the plunger body 162 adheres to the first molding tool 304, 306 as the table 308 rotates. A sensor 344 is disposed within one or more of the vacuum slots 342 and is communicatively coupled to the processor of the molding system 300 to monitor and report the status of the plunger body 162 on the first molding tool 304. The sensor 344 communicates with the processor when the plunger body 162 is not fully seated on the vacuum slot 342 or when the sensor 344 detects a dent or other defect in the plunger body 162. If the sensor detects a defect or improper placement of the plunger body 162 on the cavity 320A, the sensor 344 transmits that data to the processor indicating that the condition has been met. The processor is programmed to activate an alarm in the system 300 if these conditions are met, alerting the operator to reload the first forming tool 304. The alarm can also be associated with a lockdown feature in the forming system 300 such that the table 308 cannot rotate if the alarm is activated.

[0144] 18A, the platform 330 includes a mounting pin 346 and ejector pins 348, 350 for securing the plunger body 162 to the first mold tool 304 and ejecting the plunger body 162 from the first mold tool 304. The mounting pin 346 is spaced apart from the first mold portion 332A and is configured to receive the hanger 170 of the plunger body 162. Each of the mounting pins 346 extends through one of the openings 172 formed in the hanger 170 to securely couple the plunger body 162 to the cavity 320A. The first ejector pin 348 is within the negative head space 332A of the cavity 320A and the second ejector pin 350 is within the negative foot space 336A of the cavity 320A. To remove the overmolded plunger body from the cavity 320A, the ejector pins 348, 350 are actuated to extend from the platform 330 into the overmolded plunger body and push the overmolded plunger body out of the cavity 320A. As shown in FIG. 18A, the ejector pins 348, 350 retract into the cavity 320A when not in use and remain in the retracted position until the overmolded plunger body is formed, cooled, and ready for removal, at which point the system 300 can automatically detect that these conditions are met and actuate the ejector pins 348, 350.

[0145] FIG. 18B shows a close-up of the first molded portion 332B of the second cavity 320B. The first molded portion 332B is one half of the negative head space of the head mold. As previously described, the second mold tool 404 provides a corresponding cavity with a negative head space (and negative foot space) that completes the mold 410 of the head portion 45 (and foot portion 47) of the plunger 26. FIG. 18B shows how the first molded portion of the first and second mold tools 304, 404 provides the head mold 332B with a negative collar space 352 that defines the collar 45A, first and second flange negative spaces 354, 356 that define the projections 48 or flanges extending from the collar 45A, and a top end 357 that defines a portion of the head 45 that extends away from the wavy edge 174 of the first end 164 of the plunger body 162 (FIG. 19C). At least one of the first and second flange negative spaces 354, 356 includes a distally facing angled surface 358 for forming a cam surface 49 on one or more protrusions 48. The molding of the negative foot space is further described below with respect to FIG.

[0146] 19A-19C show the plunger body 162 disposed within the first cavity 320A of the first mold tool 304. Again, step 312 of loading the plunger body 162 into the first mold tool 304 includes loading the first end 164 of the plunger body 162 into the first mold portion 332A and the second end 166 into the second mold portion 336A. Loading the plunger body includes coupling the hanger 170 of the plunger body 162 to a mounting pin 346 of the first mold tool 304. The mounting pin 346 helps maintain the position of the plunger body 162 relative to the cavity 320A as the system 300 applies various forces (e.g., rotational and axial forces) to the plunger body 162 during the molding process. The intermediate portion 334A of the cavity 320A is specifically sized to receive the cylindrical outer wall 160 of the plunger body 162 and fit snugly therewith.

[0147] In practice, as shown in Figures 19B and 19C, the first mold tool 304 engages the plunger body 162 at at least two locations 360, 362 to avoid plastic flash on the plunger body 162. The tight engagement between the outer wall 160 of the plunger body 162 and the walls 360, 362 of the first mold tool 304 reduces seepage of molten plastic from the first and second molded portions 332A, 336A when the system 300 injects molten plastic into the first and second mold tools 304, 404. In particular, the walls 360, 362 defined by the first and second molded portions 332A, 336A contact the periphery of the first and second ends 164, 166 of the plunger body 162, respectively. The walls 360, 362 of the first mold tool 304 block any molten plastic from penetrating into the middle portion 334A of the cavity 320A. As a result, the axial wall 39 of the plunger 26 remains free of molded parts.

[0148] In FIG. 19B, the second molded portion 336A of the cavity 320A not only provides intimate contact between the wall 362 and the plunger body 162, but also provides one half of the negative foot space that defines the foot portion 47 of the plunger 26. Unlike the negative head space of the first molded portion 332A, the negative foot space of the second molded portion 336A does not surround the outer wall 160 of the plunger body 162, so that the negative foot space 336A extends from the corrugated edge 176 of the plunger body 162. Rather, the second molded portions 336A of the first and second mold tools 304, 404 together provide a chamfered foot mold that surrounds the corrugated edge 176 and extends axially away from the plunger body 162. The negative foot mold 336A has a chamfered end 366, providing a self-centering feature for the plunger 26 when assembled into a syringe. In effect, the chamfered end 336 defines a chamfered portion of the foot 47 that acts as a barrier between the metal plunger body 162 and the glass of the syringe. Thus, a plunger 26 manufactured according to the methods described herein will not contact the glass of the syringe as the plunger 26 moves through the medical device 10.

[0149] 20 illustrates the step of preparing the plunger bodies 162A-D loaded on the first molding tool 304. This step includes moving the plate 322 and the core 324 toward the plurality of loaded plunger bodies 162A-D until both the plate 322 and the core 324 engage with each of the plunger bodies 162A-D. The plate 322 includes a beveled tip 368 that aligns the plunger bodies 162A-D by evenly contacting the distal ends 166A-D of the plunger bodies 162A-D. After the first molding tool 304 is fully and properly loaded (i.e., if the alarm is not activated), the system 300 actuates the plate 322 to move in the H direction from an initial position where the beveled tip 368 is spaced apart from the plunger bodies 162A-D to an engagement position where the beveled tip 368 engages the plunger bodies 162A-D.

[0150] Concurrently with or shortly after the plate 322 engages the plunger bodies 162A-D, the system 300 actuates the cores 324 to move in a direction J opposite to the direction H from an initial position in which the cores 324 are spaced apart from the plunger body 162 to an engaged position in which each core 324 is inserted into the axial chamber 168 of the plunger body 162A-D. In the illustrated example, only one core 324 is shown. However, the first mold tool 304 includes a carriage (not shown) that carries four separate cores 324 corresponding to the four separate cavities 320A-D of the first mold tool 304. When the cores 324 engage the plunger bodies 320A-D, each core 324 extends between the first molded portions 332A of the cavities into the axial chamber 168 of the plunger bodies 320A-D and along substantially the entire length of the plunger bodies 162A-D. The core 324 extends to a position D relative to the outer wall 160 of the plunger body 162 and remains in place during the injection molding step 316. This position D also corresponds to the proximal end of the first portion 55 (FIG. 4D) of the foot 47 formed during the injection molding. In other words, during the injection step 316, the molten plastic flows into the second end 166 of the plunger body 162 and into the axial chamber 168 until it reaches position D, where the core 124 blocks the molten plastic from flowing further into the axial cavity 168. The core 324 also prevents undesired penetration of the molten plastic into the top end 164 of the plunger body 162 and the remaining axial chamber 168.

[0151] FIG. 21 illustrates a second mold tool 404 constructed in accordance with the teachings of the present disclosure. The second mold tool 404 has similar features to the first mold tool 304 described above, except that the second mold tool 404 remains at station II and couples with one or more of the first mold tools 304, 306 to complete the mold 410. Elements of the second mold tool 404 in FIG. 21 that are similar to elements of the first mold tool 304 are indicated with the same reference numerals, plus 100. Descriptions of many of these elements have been omitted or even abbreviated for the sake of brevity. As previously described, the second mold tool 404 includes a plurality of cavities 420A-D corresponding to the cavities 320A-D of the first mold tool 304, and a network of grooves 440 forming a plurality of channels corresponding to the network of grooves 340 of the first mold tool 304.

[0152] 22, in step 314 of the method 310, the mold 410 is assembled by clamping the first mold tool 304 to the second mold tool 404. The platform 330 of the first mold tool 304 and the platform 430 of the second mold tool 404 sealingly mate when the first and second mold tools 304, 404 are clamped together at station II. Each mold tool 304, 404 includes a centering feature or surface 380, 480 that accurately and precisely aligns the first and second mold tools 304, 404 prior to pouring the mold 410. In fact, each surface 380, 480 allows the first and second mold tools 304, 404 to be aligned with a gap of less than 0.005 inches.

[0153] After the first and second mold tools 304, 404 are securely clamped together, the system 300 heats the clamped first and second mold tools 304, 404 with hot water (e.g., 120 degrees Celsius). Specifically, the hot water flows through the cooling and heating channels 326 of the first mold tool 304. Once the mold 410 reaches the desired elevated temperature, the system 300 injects molten plastic into the multiple channels 482 of the mold 410 in step 316 to form an overmolded plunger body 526, as shown in FIG. 23. The system 300 injects molten plastic into the mold 410 from a molten plastic source at a pressure of 800 bar.

[0154] FIG. 23 illustrates the step of injecting molten plastic into the channels of the mold 410 to form an overmolded plunger body. For example, the overmolded plunger body 526 in the first cavity 320A includes a head 545A surrounding a portion of the first end 164 and a foot 547A extending from the second end 166 of the plunger body 162. The foot 547A is at least partially bonded to the inner wall and the head 545A is bonded to the outer wall 160 of the plunger body 162. The second mold tool 404 is hidden in FIG. 23 to illustrate how the network of channels 482 of the mold 410 is formed by mating grooves 340, 440 of the first and second mold tools 304, 404. The network of channels 482 includes a first group 484 and a symmetrical second group 486 of channels 482. Figure 23 shows a first group 484 of channels 482, while Figure 24A partially shows a second group 486. However, Figure 17 shows how the grooves 340 formed in the first mold tool 304 are symmetrical about the midline M, which corresponds to the symmetry of the first and second groups of channels 482 formed by the mold 410. Each group 484, 486 of channels 382 includes a supply line 488, 492 that traverses the second mold tool 404 and fluidly connects to the network of channels 482.

[0155] A first feed line 488 (shown in phantom in FIG. 23 for clarity) is disposed between the first and second cavities 320A, 320B of the first mold tool 304 and directs injected molten plastic through the first group of channels 484 and into the first and second molded portions 332A-B, 432A-B, 336A-B, 436A-B of the first and second cavities 320A, 420A, 320B, 420B. As shown in FIG. 24A, a second feed line 490 traverses the second mold tool 404 and connects to the second group 486 of channels 382 at a location between the third cavity 320C and the fourth cavity 320D of the first mold tool 304. Similar to the first group of channels 484, the second group of channels 486 direct the injected molten plastic to the first and second portions 332C, 432C, 336D, 436D of the third and fourth cavities 320C, 420C, 320D, 420D. While the illustrated example includes two supply lines 488, 490, other exemplary molding systems 300 may include additional supply lines to connect a source of molten plastic to the first and second molding tools 304, 404. The additional supply lines may extend through one or both of the first and second molding tools 304, 404.

[0156] Each supply line 488, 490 connects a source of molten plastic to both groups of channels 484, 486 for a uniform and efficient injection molding process. The molding system 300 injects plastic with sufficient force (e.g., about 800 bar) to simultaneously fill both the negative foot spaces 336A-D, 436A-D and the negative head spaces 332A-D, 432A-D of each cavity 320A-D, 420A of the mold 410. As shown in FIG. 23, the first and second molded portions 332A, 432A, 336A, 436A of the first cavity 320A, 420A are fluidly connected by a first arm channel 492, and the first and second molded portions 332B, 432B, 336B, 436B of the second cavity 320B, 420B are fluidly connected by a second arm channel 494. The step 316 of injecting molten plastic into, for example, the first cavity 320A, 420A of the mold 410 includes forming a head 545A having a flange 548A extending radially outward from the first end 164 of the plunger body 162 and forming a cam follower 549A on one or more of the flanges 548A. The head 545A is molded around a portion of the outer wall 160 of the plunger body 162 and bonds to the scalloped edge 174 of the first end 164. The step 316 of injecting molten plastic into the mold 410 also includes forming a foot 547A in the first cavity 320A, 420A. The foot 547A is at least partially adjacent to the inner wall of the plunger body 162 and bonds to the scalloped edge 176 of the second end 166 of the plunger body 162. It will be appreciated that a similar mold is formed for each of the cavities of mold 410 .

[0157] The first and second arms 492, 494 are fluidly coupled to each other by a bridge channel 496. At both ends of each channel, the first and second arms 492, 494 are connected to first and second channels 498A-B, 500A-B that extend perpendicular to the arms 492, 494 and connect the arms 492, 494 to the first and second molded portions 332A, 432A, 336A, 436A. For example, the first and second channels 498A, 500A connect the first arm 492 to the first molded portion 332A, 432A and the second molded portion 336A, 436A of the first cavity 320A, 420A. The same applies to the connection of the first and second molded portions 332B, 432B, 336B, 436B of the second cavity 320B, 420B. The first and second arms 492, 494 are connected to each other by a bridge 495 which also connects the first group 484 and the second group 486 of channels 482 by an L channel 497. The second group 486 of channels 482 are similarly organized for filling the third and fourth cavities 320C-D, 420C-D.

[0158] As shown in Figure 23, each connecting channel 498A-B, 500A-B is curved such that at least a portion of the channel 498A-B, 500A-B is formed entirely within the first or second mold tool 304, 404. In Figures 23 and 24B, the first connecting channel 498A, 498B, 498D is curved under the overmolded head 545A, 545B, 545D and the second connecting channel 500A, 500B, 500D is curved over the overmolded foot 547A, 547B, 547D. The first connecting channels 498A-D extend under the overmolded heads 545A-D such that the beveled edges 502A-D of the first molded portions 332A-D sever the molded plastic channels when the ejector pins 348, 350 eject the overmolded plunger 526 from the cavities 320A-D. The second connecting channels 500A-D have a diameter D in the range of about 0.1 mm to about 0.2 mm such that the ejection force of the ejector pins 348, 350 snaps or breaks the molded plastic channels when the overmolded plunger body 526 is ejected from the cavities 320A-D of the first mold tool 304.

[0159] After the injection step 316 is completed, in step 318, the system 300 flushes the cooling channels 326 (FIG. 16) with cold water to harden the plastic in the mold 410. The system 300 then releases the clamp between the first mold tool 304 and the second mold tool 404 and rotates the table 308 approximately 180 degrees to position the overmolded plunger body 526 loaded on the first mold tool 304 at Station I. At Station I, the overmolded plunger body 526 is removed from the first mold tool 404. Removing the hardened plunger from the first mold tool 304 includes actuating the ejector pins 348, 350 in the first mold tool 304. An ejector pin 348, 350 located within each cavity 320A-D pushes the hardened plunger away from the platform 330 of the first mold tool 304. Ejection of the hardened plunger automatically severs or breaks the mold channels attached to the overmolded heads 545A-D and feet 547A-D, forming connections that are removed by an operator. Once the molded channels are removed, multiple plungers 26, such as plunger 26 of FIGS. 4A-4E, can be individually removed from the first mold tool 304. After the plungers 26 are removed from the molding system 300, the hangers 170 are cut from the plungers 26.

[0160] The above description describes various devices, assemblies, components, subsystems, and methods for use in connection with drug delivery devices. The devices, assemblies, components, subsystems, methods, or drug delivery devices may further include or be used in conjunction with drugs, including but not limited to the drugs identified below, and their generic and biosimilar equivalents. As used herein, the term drug may be used interchangeably with other similar terms and may be used to refer to any type of drug or therapeutic material, including traditional and non-traditional drugs, nutraceuticals, supplements, biologics, biologically active agents and compositions, large molecules, biosimilars, biological equivalents, therapeutic antibodies, polypeptides, proteins, small molecules, and generic drugs. Non-therapeutic injectable materials are also included. Drugs may be in liquid form, lyophilized form, or reconstituted from a lyophilized form. The following list of exemplary drugs should not be considered exhaustive or limiting.

[0161] The drug will be contained within a reservoir. In some cases, the reservoir is a primary container that is either filled or pre-filled with the drug for the treatment. The primary container may be a vial, cartridge, or pre-filled syringe.

[0162] In some embodiments, the reservoir of the drug delivery device may be loaded with or the device may be used with colony stimulating factors such as granulocyte colony stimulating factor (G-CSF). Such G-CSF agents include, but are not limited to, Neulasta® (pegfilgrastim, PEGylated filgastrim, PEGylated G-CSF, PEGylated hu-Met-G-CSF) and Neupogen® (filgrastim, G-CSF, hu-MetG-CSF), UDENYCA® (pegfilgrastim-cbqv), Ziextenzo® (LA-EP2006; pegfilgrastim-bmez) or FULPHILA (pegfilgrastim-bmez).

[0163] In other embodiments, the drug delivery device may contain or be used with an erythropoietin stimulating agent (ESA), which may be in liquid or lyophilized form. An ESA is any molecule that stimulates erythropoietin. In some embodiments, an ESA is an erythropoietin stimulating protein. As used herein, "erythropoietin stimulating protein" refers to any protein that directly or indirectly causes activation of the erythropoietin receptor, for example, by binding to the receptor and causing receptor dimerization. Erythropoietin stimulating proteins include erythropoietin and its variants, analogs, or derivatives that bind to and activate the erythropoietin receptor; antibodies that bind to and activate the erythropoietin receptor; or peptides that bind to and activate the erythropoietin receptor. Erythropoietin stimulating proteins include Epogen® (epoetin alfa), Aranesp® (darbepoetin alfa), Dynepo® (epoetin delta), Mircera® (methoxypolyethylene glycol-epoetin beta), Hematide®, MRK-2578, INS-22, Retacrit® (epoetin zeta), Neorecormon® (epoetin beta), Silapo® (epoetin zeta), Binocrit® (epoetin alfa), Epoetin alpha, epoetin beta, epoetin iota, epoetin omega, epoetin delta, epoetin zeta, epoetin theta, and epoetin delta, PEGylated erythropoietin, carbamylated erythropoietin, and molecules or variants or analogs thereof.

[0164] Among certain exemplary proteins are the specific proteins described below, including fusions, fragments, analogs, variants, or derivatives thereof: OPGL-specific antibodies (also referred to as RANKL-specific antibodies, peptibodies, etc.), peptibodies, related proteins, etc., including fully humanized and human OPGL-specific antibodies, particularly fully humanized monoclonal antibodies; myostatin-binding proteins, peptibodies, related proteins, etc., including myostatin-specific peptibodies; and proteins that specifically bind to the receptors for IL-4 and / or IL-13. IL-4 receptor-specific antibodies, peptibodies, related proteins, and the like, which inhibit activity mediated by the binding of IL-4 receptor; interleukin 1-receptor 1 ("IL1-R1") specific antibodies, peptibodies, related proteins, and the like; Ang2 specific antibodies, peptibodies, related proteins, and the like; NGF specific antibodies, peptibodies, related proteins, and the like; CD22 specific antibodies, peptibodies, related proteins, and the like, particularly a dimer of human-mouse monoclonal hLL2 gamma chain disulfide bound to human-mouse monoclonal hLL2 kappa chain. human CD22-specific antibodies, including but not limited to, humanized and fully human antibodies, including but not limited to, humanized and fully human monoclonal antibodies, particularly including but not limited to, human CD22-specific IgG antibodies, such as the human CD22-specific fully human antibody of epratuzumab (CAS Registry Number 501423-23-0); IGF-1 receptor-specific antibodies, peptibodies, and related proteins, including but not limited to, anti-IGF-1R antibodies; B7RP-specific fully human monoclonal IgG2 including, but not limited to, antibodies, including, but not limited to, fully human IgG2 monoclonal antibodies that bind to an epitope in the first immunoglobulin-like domain of B7RP-1, which inhibit the interaction of B7RP-1 with its natural receptor, ICOS, on activated T cells, B-7 related protein 1 specific antibodies, peptibodies, related proteins, and the like (also referred to as "B7RP-1" and B7H2, ICOSL, B7h, and CD275); IL-15 specific antibodies, peptibodies, related proteins, and the like, particularly humanized monoclonal antibodies, including, but not limited to, HuMax IL-15 antibodies and related proteins, such as, for example, 145c7;IFN gamma specific antibodies, peptibodies, related proteins, and the like, including but not limited to human IFN gamma specific antibodies, and including but not limited to fully human anti-IFN gamma antibodies; TALL-1 specific antibodies, peptibodies, related proteins, and the like, as well as other TALL specific binding proteins; parathyroid hormone ("PTH") specific antibodies, peptibodies, related proteins, and the like; thrombopoietin receptor ("TPO-R") specific antibodies, peptibodies, related proteins, and the like; hepatocyte growth factor ("HGF") specific antibodies, peptibodies, related proteins, and the like, including those targeting HGF / SF. ) specific antibodies, peptibodies, related proteins, etc.; cMet axis (HGF / SF:c-Met), such as fully human monoclonal antibodies that neutralize hepatocyte growth factor specific antibodies; TRAIL-R2 specific antibodies, peptibodies, related proteins, etc.; Activin A specific antibodies, peptibodies, proteins, etc.; TGF-beta specific antibodies, peptibodies, related proteins, etc.; Amyloid-beta protein specific antibodies, peptibodies, related proteins, etc.; proteins that bind to c-Kit and / or other stem cell factor receptors. including, but not limited to, c-Kit specific antibodies, peptibodies, related proteins, etc.; OX40L specific antibodies, peptibodies, related proteins, etc., including, but not limited to, proteins that bind OX40L and / or other ligands of the OX40 receptor; Activase® (alteplase, tPA); Aranesp® (darbepoetin alfa), erythropoietin [30-asparagine, 32-threonine, 87-valine, 88-asparagine, 90-threonine], darbepoetin alfa, a new erythropoiesis-stimulating protein Protein (NESP); Epogen® (epoetin alfa or erythropoietin); GLP-1, Avonex® (interferon beta-1a); Bexxar® (tositumomab, an anti-CD22 monoclonal antibody); Betaseron® (interferon-beta); Campath® (alemtuzumab, an anti-CD52 monoclonal antibody); Dynepo® (epoetin delta); Velcade® (bortezomib); MLN0002 (anti-α4β7 mAb); MLN1202 (anti-CCR2 chemokine receptor mAb);Enbrel® (etanercept, TNF receptor / Fc fusion protein, TNF blocker); Eprex® (epoetin alfa); Erbitux® (cetuximab, anti-EGFR / HER1 / c-ErbB-1); Genotropin® (somatropin, human growth hormone); Herceptin® (trastuzumab, anti-HER2 / neu(erbB2) receptor mAb); Kanjinti™ (trastuzumab-anns) anti-HER2 monoclonal antibody, a biosimilar of Herceptin® or another product containing trastuzumab for the treatment of breast or gastric cancer; Humatrope® (somatropin, human growth hormone); Humira® (adalimumab); Vectibix (registered ® (panitumumab), Xgeva® (denosumab), Prolia® (denosumab), immunoglobulin G2 human monoclonal antibody against RANK ligand, Enbrel® (etanercept, TNF receptor / Fc fusion protein, TNF blocker), Nplate® (romiplostim), rilotumumab, ganitumab, conatumumab, brodalumab, insulin in solution; Infergen® (interferon alfacon-1); Natrecor® (nesiritide; recombinant human B-type natriuretic peptide (hBNP); Kineret® (anakinra); Leukine® (sargamostim, rhuGM-CSF); LymphoCide® (epratuzumab, anti-CD22 mAb); Benlysta™ (lymphostat B, belimumab, anti-BlyS mAb); Metalyse® (tenecteplase, t-PA analog); Mircera® (methoxypolyethylene glycol-epoetin beta); Mylotarg® (gemtuzumab ozogamicin); Raptiva® (efalizumab); Cimzia® (certolizumab pegol, CDP 870); Soliris™ (eculizumab); pexelizumab (anti-complement C5); Numax® (MEDI-524); Lucentis® (ranibizumab);Panorex® (17-1A, edrecolomab); Trabio® (lerdelimumab); TheraCim hR3 (nimotuzumab); Omnitarg (pertuzumab, 2C4); Osidem® (IDM-1); OvaRex® (B43.13); Nuvion® (vigilizumab); cantuzumab mertansine (huC242-DM1); NeoRecormon® (epoetin beta); Neumega® (oprelvekin, human interleukin-11); Orthoclone OKT3® (muromonab-CD3, anti-CD3 monoclonal antibody); Procrit® (epoetin alpha); Remicade® (infliximab, anti-TNFα monoclonal antibody); Reopro® (abciximab, anti-GP lIb / Ilia receptor monoclonal antibody; Actemra® (anti-IL6 receptor mAb); Avastin® (bevacizumab), HuMax-CD4 (zanolimumab); Mvasi™ (bevacizumab-awwb); Rituxan® (rituximab, anti-CD20 mAb);Tarceva® (erlotinib);Roferon-A®-(interferon alpha-2a);Simulect® (basiliximab);Prexige® (lumiracoxib);Synagis® (palivizumab);145c7-CHO (anti-IL15 antibody, see U.S. Pat. No. 7,153,507);Tysabri® (natalizumab, anti-α4 integrin mAb);Valortim® (MDX-1303, anti-B. anthracis protective antigen mAb);ABthrax®;Xolair® (omalizumab);ETI211 (anti-MRSA mAb);IL-1 trap (Fc portion of human IgG1 and extracellular domain of both IL-1 receptor components (type I receptor and receptor accessory protein));VEGF trap (IgG1 Ig domain of VEGFR1 fused to Fc; Zenapax® (daclizumab); Zenapax® (daclizumab, an anti-IL-2Rα mAb);Zevalin® (ibritumomab tiuxetan); Zetia® (ezetimibe); Orencia® (atacicept, TACI-Ig); anti-CD80 monoclonal antibody (galiximab); anti-CD23 mAb (lumiliximab); BR2-Fc (huBR3 / huFc fusion protein, soluble BAFF antagonist); CNTO 148 (golimumab, anti-TNFα mAb); HGS-ETR1 (mapatuzumab; human anti-TRAIL receptor-1 mAb); HuMax-CD20 (ocrelizumab, anti-CD20 human mAb); HuMax-EGFR (zalutumumab); M200 (volociximab, anti-α5β1 integrin mAb); MDX-010 (ipilimumab, anti-CTLA-4 mAb and VEGFR-1 (IMC-18F1); anti-BR3 mAbs; anti-C. difficile toxin A and toxin BC mAbs MDX-066 (CDA-1) and MDX-1388; anti-CD22 dsFv-PE38 conjugates (CAT-3888 and CAT-8015); anti-CD25 mAb (HuMax-TAC); anti-CD3 mAb (NI-0401); adecatumumab; anti-CD30 mAb (MDX-060); MDX-1333 (anti-IFNAR); anti-CD38 mAb (HuMax CD38); anti-CD40L mAb; anti-Cripto mAb; anti-CTGF idiopathic pulmonary fibrosis stage 1 fibrogen (FG-3019); anti-CTLA4 mAb; anti-eotaxin 1 mAb (CAT-213); anti-FGF8 mAb; anti-ganglioside GD2 mAb;Anti-ganglioside GM2 mAb;Anti-GDF-8 human mAb (MYO-029);Anti-GM-CSF receptor mAb (CAM-3001);Anti-HepC mAb (HuMax HepC);Anti-IFNα mAb (MEDI-545, MDX-198);Anti-IGF1R mAb;Anti-IGF-1R mAb (HuMax-Inflam);Anti-IL12 mAb (ABT-874); anti-IL12 / IL23 mAb (CNTO 1275); anti-IL13 mAb (CAT-354); anti-IL2Ra mAb (HuMax-TAC); anti-IL5 receptor mAb; anti-integrin receptor mAb (MDX-018, CNTO 95);Anti-IP10 ulcerative colitis mAb (MDX-1100);BMS-66513;Anti-mannose receptor / hCGβ mAb (MDX-1307); anti-mesothelin dsFv-PE38 conjugate (CAT-5001); anti-PD1 mAb (MDX-1106 (ONO-4538)); anti-PDGFRα antibody (IMC-3G3); anti-TGFβ mAb (GC-1008); anti-TRAIL receptor-2 human mAb (HGS-ETR2); anti-TWEAK mAb; anti-VEGFR; / Flt-1 mAb; and anti-ZP3 mAb (HuMax-ZP3).

[0165] In some embodiments, the drug delivery device may contain or be used in conjunction with a sclerostin antibody, such as, but not limited to, romosozumab, brosozumab, BPS 804 (Novartis), Evenity™ (romosozumab-aqqg), another product containing romosozumab for the treatment of postmenopausal osteoporosis and / or fracture healing, and in other embodiments, a monoclonal antibody (IgG) that binds to human proprotein convertase subtilisin / kexin type 9 (PCSK9). Such PCSK9-specific antibodies include, but are not limited to, Repatha® (evolocumab) and Praluent® (alirocumab). In other embodiments, the drug delivery device may contain or be used in conjunction with rilotumumab, bixalomer, trebananib, ganitumab, conatumumab, motesanib niphosphate, brodalumab, vidupiprant, or panitumumab. In some embodiments, the reservoir of the drug delivery device may be loaded with, or the device may be used in conjunction with, IMLYGIC® (talimogene laherparepvec) or another oncolytic HSV for the treatment of melanoma or other cancers, including but not limited to OncoVEXGALV / CD; OrienX010; G207, 1716; NV1020; NV12023; NV1034; and NV1042. In some embodiments, the drug delivery device may contain, or be used in conjunction with, an endogenous tissue inhibitor of metalloproteinases (TIMP), such as but not limited to TIMP-3. In some embodiments, the drug delivery device may contain, or be used in conjunction with Aimovig® (erenumab-aooe), anti-human CGRP-R (calcitonin gene-related peptide type 1 receptor), or another product containing erenumab for the treatment of migraines. Antagonistic antibodies to the human calcitonin gene-related peptide (CGRP) receptor, such as, but not limited to, erenumab, and bispecific antibody molecules targeting the CGRP receptor and other headache targets, may also be delivered using the drug delivery devices of the present disclosure.In addition, bispecific T cell engager (BiTE®) molecules, such as but not limited to BLINCYTO® (blinatumomab), can be used in or with the drug delivery device of the present disclosure. In some embodiments, the drug delivery device may contain or be used with an APJ large molecule agonist, such as but not limited to apelin or an analogue thereof. In some embodiments, a therapeutically effective amount of anti-thymic stromal lymphopoietin (TSLP) or a TSLP receptor antibody is used in or with the drug delivery device of the present disclosure. In some embodiments, the drug delivery device may contain or be used with Avsola™ (infliximab-axxq), an anti-TNF alpha monoclonal antibody, a biosimilar of Remicade® (infliximab) (Janssen Biotech, Inc.), or another product containing infliximab for the treatment of autoimmune diseases. In some embodiments, the drug delivery device may contain or be used in conjunction with Kyprolis® (carfilzomib), (2S)-N-((S)-1-((S)-4-methyl-1-((R)-2-methyloxiran-2-yl)-1-oxopentan-2-ylcarbamoyl)-2-phenylethyl)-2-((S)-2-(2-morpholinoacetamido)-4-phenylbutanamido)-4-methylpentanamide, or another product containing carfilzomib for the treatment of multiple myeloma. In some embodiments, the drug delivery device may contain or be used in conjunction with Otezla® (apremilast), N-[2-[(1S)-1-(3-ethoxy-4-methoxyphenyl)-2-(methylsulfonyl)ethyl]-2,3-dihydro-1,3-dioxo-1H-isoindol-4-yl]acetamide, or another product containing apremilast for the treatment of various inflammatory diseases.In some embodiments, the drug delivery device may contain or be used in conjunction with Parsabiv™ (etelcalcetide HCl, KAI-4169) or another product containing etelcalcetide HCl for the treatment of secondary hyperparathyroidism (sHPT), such as in patients with chronic kidney disease (KD) on hemodialysis. In some embodiments, the drug delivery device may contain or be used in conjunction with ABP 798 (rituximab), a biosimilar candidate of Rituxan® / MabThera™, or another product containing an anti-CD20 monoclonal antibody. In some embodiments, the drug delivery device may contain or be used in conjunction with a VEGF antagonist, such as a non-antibody VEGF antagonist, and / or a VEGF trap, such as aflibercept (Ig domain 2 from VEGFR1 and Ig domain 3 from VEGFR2 fused to the Fc domain of IgG1). In some embodiments, the drug delivery device may contain or be used with ABP 959 (eculizumab), a biosimilar candidate of Soliris®, or another product containing a monoclonal antibody that specifically binds to complement protein C5. In some embodiments, the drug delivery device may contain or be used with rogivafusp alfa (formerly AMG 570), a novel bispecific antibody-peptide conjugate that simultaneously blocks ICOSL and BAFF activity. In some embodiments, the drug delivery device may contain or be used with omecamtib mecarbil, a small molecule selective cardiac myosin activator, or myotrope, that directly targets the contractile machinery of the heart, or another product containing a small molecule selective cardiac myosin activator. In some embodiments, the drug delivery device may contain sotorasib (formerly known as AMG 510), a KRAS. G12C Small molecule inhibitors, or KRAS G12CIt may contain or be used with another product containing a small molecule inhibitor. In some embodiments, the drug delivery device may contain or be used with another product containing tezepelumab, a human monoclonal antibody that inhibits the action of thymic stromal lymphopoietin (TSLP), or a human monoclonal antibody that inhibits the action of TSLP. In some embodiments, the drug delivery device may contain or be used with another product containing AMG 714, a human monoclonal antibody that binds to interleukin-15 (IL-15), or a human monoclonal antibody that binds to interleukin-15 (IL-15). In some embodiments, the drug delivery device may contain or be used with another product containing AMG 890, a small interfering RNA (siRNA) that reduces lipoprotein (a), also known as Lp(a), or a small interfering RNA (siRNA) that reduces lipoprotein (a). In some embodiments, the drug delivery device may contain or be used with ABP 654 (human IgG1 kappa antibody), a biosimilar candidate of Stelara®, or another product that contains a human IgG1 kappa antibody and / or binds to the p40 subunit of the human cytokines interleukin (IL)-12 and IL-23. In some embodiments, the drug delivery device may contain or be used with Amjevita™ or Amgevita™ (formerly ABP 501) (mab anti-TNF human IgG1), a biosimilar candidate of Humira®, or another product that contains a human mab anti-TNF human IgG1. In some embodiments, the drug delivery device may contain or be used with AMG 160, or another product that contains a half-life extended (HLE) anti-prostate specific membrane antigen (PSMA) x anti-CD3 BiTE® (bispecific T cell engager) construct. In some embodiments, the drug delivery device may contain or be used in conjunction with another product containing AMG 119 or delta-like ligand 3 (DLL3) CAR T (chimeric antigen receptor T cell) cell therapy.In some embodiments, the drug delivery device may contain or be used with another product containing AMG 119, or a delta-like ligand 3 (DLL3) CAR T (chimeric antigen receptor T cell) cell therapy. In some embodiments, the drug delivery device may contain or be used with another product containing AMG 133, or a gastric inhibitory polypeptide receptor (GIPR) antagonist and a GLP-1R agonist. In some embodiments, the drug delivery device may contain or be used with another product containing AMG 171, or a growth differentiation factor 15 (GDF15) analog. In some embodiments, the drug delivery device may contain or be used with another product containing AMG 176, or a small molecule inhibitor of myeloid cell leukemia 1 (MCL-1). In some embodiments, the drug delivery device may contain or be used with another product containing AMG 199, or a half-life extended (HLE) bispecific T cell engager construct (BiTE®). In some embodiments, the drug delivery device may contain or be used with AMG 256, or another product containing an anti-PD-1 x IL21 mutein and / or an IL-21 receptor agonist designed to selectively activate the interleukin 21 (IL-21) pathway in programmed cell death-1 (PD-1) positive cells. In some embodiments, the drug delivery device may contain or be used with AMG 330, or another product containing an anti-CD33 x anti-CD3 BiTE® (bispecific T cell engager) construct. In some embodiments, the drug delivery device may contain or be used with AMG 404, or another product containing a human anti-programmed cell death-1 (PD-1) monoclonal antibody being investigated as a treatment for patients with solid tumors.In some embodiments, the drug delivery device may contain or be used with AMG 427, or another product containing a half-life extended (HLE) anti-fms-like tyrosine kinase 3 (FLT3) x anti-CD3 BiTE® (bispecific T cell engager) construct. In some embodiments, the drug delivery device may contain or be used with AMG 430, or another product containing an anti-Jagged-1 monoclonal antibody. In some embodiments, the drug delivery device may contain or be used with AMG 506, or another product containing a multispecific FAP x 4-1BB targeted DARPin® biologic being investigated as a treatment for solid tumors. In some embodiments, the drug delivery device may contain or be used with AMG 509, or another product containing a bivalent T cell engager and designed using XmAb® 2+1 technology. In some embodiments, the drug delivery device may contain AMG 56. 2, or another product containing a half-life extended (HLE) CD19×CD3 BiTE® (bispecific T cell engager) construct. In some embodiments, the drug delivery device may contain or be used with another product containing ephavalukin alpha (formerly AMG 592) or an IL-2 mutein Fc fusion protein. In some embodiments, the drug delivery device may contain or be used with another product containing AMG 596, or a CD3×Epidermal Growth Factor Receptor vIII (EGFRvIII) BiTE® (bispecific T cell engager) molecule. In some embodiments, the drug delivery device may contain or be used with AMG 673, or another product containing a half-life extended (HLE) anti-CD33×anti-CD3 BiTE® (bispecific T cell engager) construct. In some embodiments, the drug delivery device may contain or be used with AMG 701 or another product containing a half-life extended (HLE) anti-B cell maturation antigen (BCMA) x anti-CD3 BiTE® (bispecific T cell engager) construct. In some embodiments, the drug delivery device may contain or be used with AMG 757 or another product containing a half-life extended (HLE) anti-delta-like ligand 3 (DLL3) x anti-CD3 BiTE® (bispecific T cell engager) construct. In some embodiments, the drug delivery device may contain or be used with AMG 910 or another product containing a half-life extended (HLE) epithelial cell tight junction component protein claudin 18.2 x CD3 BiTE® (bispecific T cell engager) construct.

[0166] The drug delivery devices, assemblies, components, subsystems, and methods have been described in terms of exemplary embodiments, but are not limited thereto. The detailed description should be construed as merely exemplary and does not describe all possible embodiments of the present disclosure. Many alternative embodiments can be implemented using either current technology or technology developed after the filing date of this patent, and such embodiments still fall within the scope of the claims that define the invention disclosed herein.

[0167] Those skilled in the art will understand that numerous modifications, alterations, and combinations can be made to the above-described embodiments without departing from the spirit and scope of the invention disclosed herein, and such modifications, alterations, and combinations are to be construed as falling within the scope of the inventive concept.

Claims

1. A method for manufacturing a plunger for a drug delivery device, comprising: forming a plunger body having an inner wall and an outer wall defining an axial chamber, the plunger body including a first end and a second end opposite the first end; loading the plunger body into a cavity of a first mold tool of a molding system; coupling the second mold tool to the first mold tool to form a plurality of channels defined by grooves in first and second mold tools, the second mold tool including a cavity sized to receive a portion of the plunger body when the plunger body is disposed within the cavity of the first mold tool; injecting molten plastic into the plurality of channels to form an overmolded plunger body having at least one overmolded portion; A method comprising:

2. The method of claim 1, wherein injecting molten plastic includes injecting molten plastic to form a head coupled to the first end of the plunger body and a foot coupled to the second end of the plunger body, the foot being at least partially coupled to the inner wall of the plunger body and the head being coupled to the outer wall.

3. A method as described in claim 1 or 2, further comprising moving the first molding tool from a first position to a second position prior to coupling the second molding tool to the first molding tool.

4. A method according to any one of claims 1 to 3, further comprising inserting a rod into the axial chamber of the plunger body prior to coupling the first molding tool to the second molding tool.

5. The method of any one of claims 1 to 4, wherein injecting into the plurality of channels includes injecting into a curved channel formed in the second molding tool, the curved channel including a diameter in the range of about 0.1 mm to about 0.2 mm and coupled to a second molded portion of the cavity, the cavity being at least partially defined by a first molded portion, an intermediate portion, and the second molded portion.

6. A method according to any one of claims 1 to 5, further comprising removing the hardened plunger from the first moulding tool by actuating an ejector pin in the first moulding tool, the ejector pin pushing the hardened plunger away from the cavity formed in the first moulding tool.

7. A method according to any one of claims 1 to 6, wherein loading the plunger bodies includes loading a plurality of plunger bodies onto the first molding tool of the molding system, the first molding tool including a plurality of cavities.

8. A method according to any one of claims 1 to 7, wherein loading the plunger body into the cavity includes positioning the plunger body over a vacuum slot formed in a wall of the first molding tool, the vacuum slot being configured to adhere the plunger body to the molding tool.

9. The method of claim 1, wherein forming the plunger bodies comprises stamping a plurality of plunger bodies from a sheet metal blank.

10. A method according to any one of claims 1 to 9, wherein forming the plunger body comprises cutting a corrugated edge into a sheet metal blank and bending the corrugated edge so that the first end of the plunger body includes a corrugated edge bent outwardly relative to the axial chamber.

11. A method according to any one of claims 1 to 10, wherein forming the plunger body comprises cutting a corrugated edge into a sheet metal blank and bending the corrugated edge such that the second end of the plunger body includes the corrugated edge bent inwardly toward the axial chamber.

12. A method of molding a plunger for a drug delivery device, comprising the steps of: loading a plunger body into a cavity of a first mold tool of a molding system, the plunger body including an inner wall defining an axial chamber, an outer wall, a first end, and a second end opposite the first end, the cavity at least partially defining a first mold portion, an intermediate portion, and a second mold portion; coupling a second mold tool to the first mold tool to form a plurality of channels defined by grooves in the first and second mold tools; injecting molten plastic into the plurality of channels of the first and second mold tools and into the first and second mold portions to form an overmolded plunger body, the overmolded plunger body including a head coupled to the outer wall and at least partially surrounding the first end of the plunger body, and a foot coupled to the second end of the plunger body; A method comprising:

13. The method of claim 12, further comprising moving the first molding tool from a first position to a second position prior to coupling the second molding tool to the first molding tool.

14. The method of claim 13, wherein moving the first molding tool includes rotating a movable table at least 180 degrees, and the first molding tool is mounted to a surface of the movable table.

15. A method according to any one of claims 12 to 14, wherein injecting molten plastic into the plurality of channels comprises injecting molten plastic into the second molding tool when the first molding tool is coupled to the second molding tool.

16. A method according to any one of claims 12 to 15, further comprising inserting a rod into the axial chamber of the plunger body prior to coupling the first molding tool to the second molding tool.

17. A method according to any one of claims 12 to 16, wherein injecting molten plastic into the plurality of channels comprises injecting molten plastic into a curved channel formed in the second molding tool, the curved channel being coupled to the second molded portion of the cavity.

18. A method according to any one of claims 12 to 17, wherein loading the plunger body includes loading the first end into the first molded portion and loading the second end into the second molded portion of the cavity.

19. A method according to any one of claims 12 to 18, wherein injecting molten plastic into the plurality of channels comprises injecting molten plastic into the first and second moulding tools, the plurality of channels extending between the first and second moulding portions of the first moulding tool and between the first and second moulding portions of the second moulding tool.

20. The method of claim 19, wherein injecting molten plastic into the first and second molding tools includes forming the head including at least one flange extending radially outward from the plunger body, and forming a cam follower on the at least one flange.

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