Actuator assembly for drug delivery system

The needle actuator assembly with a lockout mechanism and spring arm ensures controlled and safe self-administration of larger fluid volumes by maintaining skin contact and preventing accidental activation, addressing the challenge of extended injection times in automatic injection devices.

JP2025000976AActive Publication Date: 2025-01-07BECTON DICKINSON & CO
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Patent Information

Application Number
JP2024174441
Authority / Receiving Office
JP · JP
Patent Type
Applications
Current Assignee / Owner
Priority Date
2017-06-07
Filing Date
2024-10-03
Publication Date
2025-01-07
Estimated Expiration
2037-06-08

AI Technical Summary

Technical Problem

Existing automatic injection devices struggle with maintaining contact between the device and the patient's skin for extended injection times, especially when administering large volumes of fluid, and are often too large for self-administration in a home environment.

Method used

A needle actuator assembly with a housing, needle, and actuator button that includes a lockout mechanism to prevent premature movement, a spring arm for biasing the actuator button, and bearing surfaces to control the movement of the needle between retracted and extended positions, ensuring proper injection timing and preventing accidental activation.

Benefits of technology

The assembly allows for controlled and safe self-administration of larger fluid volumes by maintaining skin contact during the injection, preventing accidental needle retraction, and providing clear visual indicators of the injection status.

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Abstract

To provide a drug delivery system.SOLUTION: An actuator assembly for a drug delivery system includes: a housing; a driving assembly; a needle; a needle actuator body where the needle moves from a pre-use position of a storage position to a use position of an extended position and a post-use position of the storage position; and an actuator button received within the housing, movable between a first position and a second position, and including a lockout arm. When the actuator button moves from the first position to the second position, the body moves from the pre-use position to the use position, the lockout arm is engaged and disposed below a button contact surface of the body, restricts a movement of the actuator button from the second position to the first position; when the body is at the pre-use position, the lockout arm is disposed above the button contact surface of the body and prevents the body from moving upward.SELECTED DRAWING: Figure 17
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Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims priority to U.S. Provisional Application No. 62 / 347,933, filed June 9, 2016, and U.S. Patent Application No. 15 / 616,235, filed June 7, 2017, each of which is incorporated by reference in its entirety.

[0002] FIELD OF THE DISCLOSURE The present disclosure relates generally to infusion devices and methods for delivering fluids into a patient's body by injection. [Background technology]

[0003] Various types of automatic injection devices have been developed to allow drug solutions and other liquid therapeutic preparations to be administered or self-injected by untrained personnel. Generally, these devices include a reservoir pre-filled with the liquid therapeutic preparation and some type of automatic needle injection mechanism that can be triggered by the user. When the volume of fluid or drug to be administered is less than a certain volume, typically 1 mL, automatic injection devices with an injection time of about 10 to 15 seconds are typically used. When the volume of fluid or drug to be administered exceeds 1 mL, the injection time is generally longer, resulting in difficulty for the patient to maintain contact between the device and the target area of ​​the patient's skin. Furthermore, the greater the amount of drug administered, the longer the injection time is desirable. The traditional way in which a drug is slowly injected into a patient is to start an IV and slowly inject the drug into the patient's body. Such procedures are typically performed in a hospital or outpatient environment. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2013 / 155153 [Patent Document 2] International Publication No. 2014 / 179774 [Patent Document 3] International Publication No. 2015 / 081337 Summary of the Invention [Problem to be solved by the invention]

[0005] Certain devices allow for self-injection in a home environment, allowing the liquid therapeutic preparation to be gradually injected into the patient's skin. In some cases, these devices are small enough (both in height and overall size) to allow them to be "worn" by the patient while the liquid therapeutic preparation is being injected into the patient's body. These devices typically include a pump or other type of ejection mechanism to force the liquid therapeutic preparation to flow from a reservoir into an injection needle. Such devices also typically include a valve or flow control mechanism to cause the liquid therapeutic preparation to begin flowing at the appropriate time, and a trigger mechanism to initiate the injection. [Means for solving the problem]

[0006] In one embodiment, a needle actuator assembly of a drug delivery system includes a housing, a needle having a retracted position and an extended position, a needle actuator body contained within the housing and configured to move from a pre-use position in which the needle is in the retracted position to a use position in which the needle is in the extended position and to a post-use position in which the needle is in the retracted position, the needle actuator body having a button contact surface, and an actuator button received by the housing, the actuator button being movable relative to the housing between a raised position (first position) and a depressed position (second position) with the actuator button including a lockout arm, movement of the actuator button from the raised position to the depressed position moves the needle actuator body from the pre-use position to the use position, and when the needle actuator body is in the use position, the lockout arm of the actuator button engages the button contact surface of the needle actuator body to limit movement of the actuator button from the depressed position to the raised position.

[0007] The lockout arm of the actuator button may be disengaged from the button contact surface of the needle actuator body when the needle actuator body is in the post-use position to allow movement of the actuator button from the depressed position to the raised position. A portion of the needle actuator body may engage the actuator button when the needle actuator body is in the post-use position to limit movement of the actuator button from the raised position to the depressed position.

[0008] The assembly may include a first bearing surface, a second bearing surface disposed opposite the first bearing surface, and a spring arm. The assembly may include a button spring, the spring arm of the button spring configured to bias the actuator button to a raised position. The actuator button may be movable from a first axial position to a second axial position spaced from the first axial position, and the actuator button may be limited in movement from the raised position to a depressed position when the actuator button is in the first axial position. The housing may include a first bearing bevel and a second bearing bevel spaced from the first bearing bevel, the first bearing surface of the button spring engaging the first bearing bevel of the housing, and the second bearing surface of the button spring engaging the second bearing bevel of the housing. One of the first and second bearing bevels may include a stopper configured to prevent the actuator button from moving from the second axial position to the first axial position. The housing may include a spring arm bearing surface configured to engage a spring arm of the button spring. The spring arm bearing surface may include a stop configured to prevent movement of the actuator button from the second axial position to the first axial position.

[0009] In a further aspect, a needle actuator assembly of a drug delivery system includes a housing, a needle having a retracted position and an extended position, a needle actuator body contained within the housing and configured to move from a pre-use position in which the needle is in the retracted position to a use position in which the needle is in the extended position and to a post-use position in which the needle is in the retracted position, and an actuator button received by the housing. The actuator button is movable from a first axial position relative to the housing to a second axial position spaced from the first axial position and is movable between a raised position and a depressed position relative to the housing. The actuator button is restricted from moving from the raised position to the depressed position when the actuator button is in the first axial position, and movement of the actuator button from the raised position to the depressed position moves the needle actuator body from the pre-use position to the use position.

[0010] The assembly includes a first bearing surface, a second bearing surface disposed opposite the first bearing surface, and a spring arm. The assembly may include a button spring, the spring arm of the button spring configured to bias the actuator button to a raised position. The housing may include a first bearing bevel and a second bearing bevel spaced from the first bearing bevel, the first bearing surface of the button spring engaging the first bearing bevel of the housing and the second bearing surface of the button spring engaging the second bearing bevel of the housing. One of the first and second bearing bevels may include a stopper configured to prevent the actuator button from moving from the second axial position to the first axial position. The housing may include a spring arm bearing surface configured to engage the spring arm of the button spring. The spring arm bearing surface may include a stopper configured to prevent the actuator button from moving from the second axial position to the first axial position.

[0011] The needle actuator may include a button contact surface, the actuator button including a lockout arm, and the lockout arm of the actuator button engages the button contact surface of the needle actuator body to limit movement of the needle actuator button from a depressed position to a raised position when the needle actuator body is in the use position. The lockout arm of the actuator button may disengage from the button contact surface of the needle actuator body when the needle actuator body is in the post-use position to allow movement of the actuator button from the depressed position to the raised position. A portion of the needle actuator body may engage the actuator button to limit movement of the actuator button from the raised position to the depressed position when the needle actuator body is in the post-use position. [Brief description of the drawings]

[0012] The above and other features and advantages of the present disclosure, and the manner in which they are accomplished, will become more apparent, and the disclosure itself will be better understood, by reference to the following description of the disclosed embodiments taken in conjunction with the accompanying drawings, in which:

[0013] [Figure 1] FIG. 1 is a perspective view of a drug delivery system according to one embodiment of the present invention. [Diagram 2] FIG. 2 is a perspective cross-sectional view of the drug delivery system of FIG. 1 according to one embodiment of the present invention. [Diagram 3] FIG. 3 is a front cross-sectional view of the drug delivery system of FIG. 1 according to one embodiment of the present invention. [Figure 4] FIG. 4 is a top view of the drug delivery system of FIG. 1 according to one embodiment of the present invention, showing the top of the housing of the drug delivery system in a removed and pre-use position. [Diagram 5] FIG. 5 is a top cross-sectional view of the drug delivery system of FIG. 1 according to one embodiment of the present invention, showing the drug delivery system in a pre-use position. [Figure 6] FIG. 6 is a front cross-sectional view of the drug delivery system of FIG. 1 according to one embodiment of the present invention, showing the drug delivery system in a pre-use position. [Figure 7] FIG. 7 is a top view of the drug delivery system of FIG. 1 according to one embodiment of the present invention, showing the top of the housing of the drug delivery system removed and in an initial, activated position. [Figure 8] FIG. 8 is a top cross-sectional view of the drug delivery system of FIG. 1 according to one embodiment of the present invention, showing the drug delivery system in an initial actuated position. [Figure 9] FIG. 9 is a front cross-sectional view of the drug delivery system of FIG. 1 according to one embodiment of the present invention, showing the drug delivery system in an initial actuated position. [Figure 10] FIG. 10 is a top view of the drug delivery system of FIG. 1 according to one embodiment of the present invention, showing the top of the housing of the drug delivery system removed and in the use position. [Figure 11] FIG. 11 is a top cross-sectional view of the drug delivery system of FIG. 1 according to one embodiment of the present invention, showing the drug delivery system in a position of use. [Figure 12] FIG. 12 is a front cross-sectional view of the drug delivery system of FIG. 1 according to one embodiment of the present invention, showing the drug delivery system in a position of use. [Figure 13] FIG. 13 is a top view of the drug delivery system of FIG. 1 showing the top of the housing of the drug delivery system removed and in a post-use position according to one embodiment of the present invention. [Figure 14] FIG. 14 is a top cross-sectional view of the drug delivery system of FIG. 1 according to one embodiment of the present invention, showing the drug delivery system in a post-use position. [Figure 15] FIG. 15 is a front cross-sectional view of the drug delivery system of FIG. 1 according to one embodiment of the present invention, showing the drug delivery system in a post-use position. [Figure 15A] FIG. 15A is a front cross-sectional view of the drug delivery system of FIG. 1 according to one embodiment of the present invention, showing the pads in the drug delivery system in a pre-use position. [Figure 15B] FIG. 15B is a perspective view of a drug delivery system according to one embodiment of the present invention, showing the pads in the drug delivery system in a pre-use position. [Figure 15C] FIG. 15C is a perspective view of the FIG. 1 drug delivery system according to one embodiment of the present invention, showing the pads in the drug delivery system in a pre-use position. [Figure 16] FIG. 16 is a partial cross-sectional view of a drug delivery system according to one embodiment of the present invention, showing a valve assembly. [Figure 17] FIG. 17 is a perspective view of a drive assembly of a drug delivery system according to one embodiment of the present invention. [Figure 18] FIG. 18 is a cross-sectional view of the drive assembly of FIG. 17 showing the drive assembly in a pre-use position according to one embodiment of the present invention. [Figure 19] FIG. 19 is a cross-sectional view of the drive assembly of FIG. 17 showing the drive assembly in an in-use position according to one embodiment of the present invention. [Figure 20] FIG. 20 is a cross-sectional view of the drive assembly of FIG. 17 showing the drive assembly in a post-use position according to one embodiment of the present invention. [Figure 21] 21 is a perspective view of a plunger actuation member of the drive assembly of FIG. 17 according to one embodiment of the present invention. [Figure 22] 22 is a perspective view of a first plunger member of the drive assembly of FIG. 17 according to one embodiment of the present invention. [Diagram 23] 23 is a perspective view of a plunger actuating member and a first plunger member of the drive assembly of FIG. 17 according to one embodiment of the present invention, showing the plunger actuating member engaged with the first plunger member. [Figure 24] 24 is a perspective view of the plunger actuation member and first plunger member of the drive assembly of FIG. 17 according to one embodiment of the present invention, showing the plunger actuation member disengaged from the first plunger member. [Diagram 25]FIG. 25 is a perspective view of the plunger actuating member and first plunger member of the drive assembly of FIG. 17 according to one embodiment of the present invention, showing the plunger actuating member disengaged from and axially displaced relative to the first plunger member. [Figure 26] 26 is a front view of the first and second plunger members of the drive assembly of FIG. 17 according to one embodiment of the present invention. [Figure 27] FIG. 27 is a top view of a drive assembly of a drug delivery system according to a further embodiment of the present invention. [Figure 28] FIG. 28 is a perspective view of the drive assembly of FIG. 27 according to one embodiment of the present invention. [Figure 29] FIG. 29 is a cross-sectional view of the drive assembly of FIG. 27 according to one embodiment of the present invention, showing the drive assembly in a pre-use position. [Diagram 30] FIG. 30 is a perspective view of the drive assembly of FIG. 27 according to one embodiment of the present invention, showing the drive assembly received by the bottom of the housing. [Diagram 31] FIG. 31 is a perspective view of the housing of FIG. 30 according to one embodiment of the present invention. [Diagram 32] FIG. 32 is a top view of the drive assembly of FIG. 27 illustrating engagement of the drive assembly with a portion of the needle actuator in an initial actuated position of the drive assembly according to one embodiment of the present invention. [Diagram 33] FIG. 33 is an enlarged perspective view of the drive assembly of FIG. 27 illustrating engagement of the drive assembly with a portion of the needle actuator in an initial actuated position of the drive assembly according to one embodiment of the present invention. [Diagram 34] FIG. 34 is a front view of a needle actuator assembly according to one embodiment of the present invention. [Diagram 35] FIG. 35 is a left perspective view of a needle shuttle of the needle actuator assembly of FIG. 34 according to one embodiment of the present invention. [Diagram 36]FIG. 36 is a right side perspective view of the needle shuttle of the needle actuator assembly of FIG. 34 according to one embodiment of the present invention. [Figure 37A] FIG. 37A is a front view of the needle actuator assembly of FIG. 34, showing the needle actuator assembly in a pre-use position, according to one embodiment of the present invention. [Figure 37B] FIG. 37B is a front view of the needle actuator assembly of FIG. 34 showing the needle actuator assembly in a use position according to one embodiment of the present invention. [Figure 37C] FIG. 37C is a front view of the needle actuator assembly of FIG. 34 in an initial position after use according to one embodiment of the present invention. [Figure 37D] FIG. 37D is a front view of the needle actuator assembly of FIG. 34 showing the needle actuator assembly in a post-use position according to one embodiment of the present invention. [Figure 38A] FIG. 38A is a perspective view of the needle actuator assembly of FIG. 34 in a use position according to one embodiment of the present invention. [Figure 38B] FIG. 38B is a perspective view of the needle actuator assembly of FIG. 34 in an initial position after use according to one embodiment of the present invention. [Figure 39] FIG. 39 is a perspective view of the actuator button and needle actuator assembly of FIG. 34 according to one embodiment of the present invention, showing the needle actuator assembly in an initial position after use. [Figure 40A] FIG. 40A is a cross-sectional view of the actuator button and needle actuator assembly of FIG. 34 according to one embodiment of the present invention, showing the needle actuator assembly in an initial position after use. [Figure 40B]FIG. 40B is a perspective view of the actuator button and needle actuator assembly of FIG. 34 showing the needle actuator assembly in a post-use position according to one embodiment of the present invention. [Diagram 41] FIG. 41 is a perspective view of a drive assembly of a drug delivery system according to a further embodiment of the present invention. [Diagram 42] FIG. 42 is a perspective view of the drive assembly of FIG. 41 with the top of the housing removed according to one embodiment of the present invention. [Diagram 43] FIG. 43 is a cross-sectional view of a drive assembly according to one embodiment of the present invention. [Diagram 44] FIG. 44 is a perspective view of the drive assembly of FIG. 41 according to one embodiment of the present invention. [Diagram 45] FIG. 45 is a cross-sectional view of the drive assembly of FIG. 41 according to one embodiment of the present invention, showing the drive assembly in a pre-use position. [Figure 46] FIG. 46 is a cross-sectional view of the drive assembly of FIG. 41 according to one embodiment of the present invention, showing the drive assembly in a pre-use position. [Figure 47] FIG. 47 is a top view of the drive assembly of FIG. 41 according to one embodiment of the present invention, showing the drive assembly in a pre-use position. [Figure 48] FIG. 48 is a top view of the drive assembly of FIG. 41 according to one embodiment of the present invention, showing the drive assembly in an initial actuated position. [Figure 49] FIG. 49 is a top view of the drive assembly of FIG. 41 according to one embodiment of the present invention, showing the drive assembly in an initial actuated position. [Figure 50] FIG. 50 is a top view of the drive assembly of FIG. 41 according to one embodiment of the present invention, showing the drive assembly in an initial actuated position. [Figure 51] FIG. 51 is a top view of the drive assembly of FIG. 41 according to one embodiment of the present invention, showing the drive assembly in a use position. [Figure 52]FIG. 52 is a top view of the drive assembly of FIG. 41 in accordance with one embodiment of the present invention, showing the drive assembly in a use position. [Diagram 53] FIG. 53 is a cross-sectional view of the drive assembly of FIG. 41 showing the drive assembly in a use position according to one embodiment of the present invention. [Figure 54] FIG. 54 is a top view of the drive assembly of FIG. 41 according to one embodiment of the present invention, showing the drive assembly in a use position. [Figure 55] FIG. 55 is a cross-sectional view of the drive assembly of FIG. 41 showing the drive assembly in a use position according to one embodiment of the present invention. [Figure 56] FIG. 56 is a cross-sectional view of the drive assembly of FIG. 41 showing the drive assembly in a use position according to one embodiment of the present invention. [Figure 57] FIG. 57 is a top view of the drive assembly of FIG. 41 according to one embodiment of the present invention, showing the drive assembly in a use position. [Figure 58] FIG. 58 is a top view of the drive assembly of FIG. 41 according to one embodiment of the present invention, showing the drive assembly in an initial position after use. [Figure 59] FIG. 59 is a perspective view of the drive assembly of FIG. 41 according to one embodiment of the present invention, showing the drive assembly in an initial position after use. [Figure 60] FIG. 60 is a top view of the drive assembly of FIG. 41 in accordance with one embodiment of the present invention, showing the drive assembly in a post-use position. [Figure 61] FIG. 61 is a top view of the drive assembly of FIG. 41 according to one embodiment of the present invention, showing the drive assembly in a post-use position. [Figure 62] FIG. 62 is a cross-sectional view of the drive assembly of FIG. 41 according to one embodiment of the present invention, showing the drive assembly in a pre-use position. [Figure 63] FIG. 63 is a cross-sectional view of the drive assembly of FIG. 41 according to one embodiment of the present invention, showing the drive assembly in a use position. [Figure 64] FIG. 64 is a perspective view of a drive assembly according to a further embodiment of the present invention. [Figure 65A] FIG. 65A is a front view of a needle actuator assembly according to one embodiment of the present invention, showing the needle actuator assembly in the use position. [Figure 65B] FIG. 65B is a front view of the needle actuator assembly of FIG. 65A showing the needle actuator assembly in a use position according to one embodiment of the present invention. [Figure 65C] FIG. 65C is a front view of the needle actuator assembly of FIG. 65A showing the needle actuator assembly in a use position according to one embodiment of the present invention. [Fig. 65D] FIG. 65D is a front view of the needle actuator assembly of FIG. 65A showing the needle actuator assembly in a post-use position according to one embodiment of the present invention. [Figure 65E] FIG. 65E is a front view of the needle actuator assembly of FIG. 65A showing the needle actuator assembly in a pre-use position according to one embodiment of the present invention. [Fig.65F] FIG. 65F is a cross-sectional view of the needle actuator assembly of FIG. 65A showing the needle actuator assembly in a pre-use position according to one embodiment of the present invention. [Figure 65G] FIG. 65G is a front view of the needle actuator assembly of FIG. 65A showing the needle actuator assembly in a pre-use position with the button actuator axially displaced according to one embodiment of the present invention. [Fig. 65H] FIG. 65H is a cross-sectional view of the needle actuator assembly of FIG. 65A showing the needle actuator assembly in a pre-use position with the button actuator axially displaced according to one embodiment of the present invention. [Figure 66]FIG. 66 is a perspective view of a button spring of the needle actuator assembly of FIG. 65A according to one embodiment of the present invention. [Figure 67] FIG. 67 is a perspective view of an actuator button of the needle actuator assembly of FIG. 65A according to one embodiment of the invention. [Figure 68] FIG. 68 is a cross-sectional view of the button spring and actuator button of the needle actuator assembly of FIG. 65A according to one embodiment of the present invention. [Figure 68A] FIG. 68A is a perspective view of an actuator button of the needle actuator assembly of FIG. 65A according to a further embodiment of the present invention. [Figure 68B] FIG. 68B is a bottom view of the actuator button of the needle actuator assembly of FIG. 65A, according to a further embodiment of the present invention. [Figure 68C] FIG. 68C is a front view of the actuator button of the needle actuator assembly of FIG. 65A according to a further embodiment of the present invention. [Figure 68D] FIG. 68D is a top view of the actuator button of the needle actuator assembly of FIG. 65A according to a further embodiment of the present invention, showing the actuator button in a pre-use position. [Figure 68E] FIG. 68E is a front view of the actuator button of the needle actuator assembly of FIG. 65A showing the actuator button in a pre-use position according to a further embodiment of the present invention. [Fig. 68F] FIG. 68F is a top view of the actuator button of the needle actuator assembly of FIG. 65A showing the actuator button in the use position according to a further embodiment of the present invention. [Figure 68G] FIG. 68G is a front view of the actuator button of the needle actuator assembly of FIG. 65A showing the actuator button in the use position according to a further embodiment of the present invention. [Figure 69]FIG. 69 is a top view of the actuator button of the needle actuator assembly of FIG. 65A according to one embodiment of the present invention. [Figure 70A] FIG. 70A is a schematic diagram of a drive assembly according to one embodiment of the present invention, showing the drive assembly in a pre-use position. [Figure 70B] FIG. 70B is a schematic diagram of a drive assembly according to one embodiment of the present invention, showing the drive assembly in a use position. [Figure 70C] FIG. 70C is a schematic diagram of a drive assembly according to one embodiment of the present invention, showing the drive assembly in a use position. [Fig. 70D] FIG. 70D is a schematic diagram of a drive assembly according to one embodiment of the present invention, showing the drive assembly in a use position. [Figure 70E] FIG. 70E is a schematic diagram of a drive assembly according to one embodiment of the present invention, showing the drive assembly in a use position. [Fig. 70F] FIG. 70F is a schematic diagram of a drive assembly according to one embodiment of the present invention, showing the drive assembly in a post-use position. [Fig. 70G] FIG. 70G is a schematic diagram of a drive assembly according to one embodiment of the present invention, showing the drive assembly in a post-use position. [Figure 71] FIG. 71 is a perspective view of a spacer assembly of a drug delivery system according to one embodiment of the present invention, showing the spacer assembly in an assembled, pre-use position. [Figure 72] FIG. 72 is a perspective view of the spacer assembly of FIG. 71 in accordance with one embodiment of the present invention, showing the spacer assembly in an in-use position. [Figure 73] FIG. 73 is a perspective view of the spacer assembly of FIG. 71 according to one embodiment of the present invention, showing the initial position of the spacer assembly after use. [Figure 74] FIG. 74 is a perspective view of a restricting member according to one embodiment of the present invention. [Figure 75]FIG. 75 is a front view of a spacer assembly of a drug delivery system according to a further embodiment of the present invention. [Figure 76] FIG. 76 is a top view of a spacer assembly of a drug delivery system according to one embodiment of the present invention. [Figure 77] FIG. 77 is a perspective view of the spacer assembly of FIG. 76 according to one embodiment of the present invention. [Figure 78] FIG. 78 is a cross-sectional view of the spacer assembly of FIG. 76 according to one embodiment of the present invention. [Figure 79] FIG. 79 is a perspective view of a spacer assembly of a drug delivery system according to a further embodiment of the present invention. [Figure 80] FIG. 80 is a perspective view of a spacer assembly of a drug delivery system according to another embodiment of the present invention. [Figure 81A] FIG. 81A is a cross-sectional view of the spacer assembly of FIG. 80 showing the spacer assembly in a pre-assembled position according to one embodiment of the present invention. [Fig. 81B] FIG. 81B is a cross-sectional view of the spacer assembly of FIG. 80 showing the assembled position of the spacer assembly according to one embodiment of the present invention. [Figure 82] FIG. 82 is a perspective view of a drive assembly of a drug delivery system according to one embodiment of the present invention. [Figure 83] FIG. 83 is a perspective view of the drive assembly of FIG. 82 with the top of the housing removed according to one embodiment of the present invention. [Figure 84] FIG. 84 is a cross-sectional view of the drive assembly of FIG. 82 showing the drive assembly in a pre-use position according to one embodiment of the present invention. [Figure 85] FIG. 85 is an enlarged cross-sectional view of the drive assembly of FIG. 82 according to one embodiment of the present invention, showing the drive assembly in a pre-use position. [Figure 86] FIG. 86 is a top view of the biasing member of the drive assembly of FIG. 82 according to one embodiment of the present invention. [Figure 87]FIG. 87 is a perspective view of the drive assembly of FIG. 82 showing a limiting member engaged with the drive assembly according to one embodiment of the present invention. [Figure 88] FIG. 88 is a perspective view of a drive assembly of a drug delivery system according to one embodiment of the present invention. [Figure 89] FIG. 89 is a perspective view of the drive assembly of FIG. 88 according to one embodiment of the present invention, showing the drive assembly in a pre-use position. [Figure 90] FIG. 90 is a cross-sectional view of the drive assembly of FIG. 88 according to one embodiment of the present invention. [Figure 91] FIG. 91 is a perspective view of the drive assembly of FIG. 88 according to one embodiment of the present invention, showing the drive assembly in a post-use position. [Figure 92] FIG. 92 is a cross-sectional view of the drive assembly of FIG. 88 showing the drive assembly in a pre-use position according to one embodiment of the present invention. [Figure 93] FIG. 93 is a front view of the drive assembly of FIG. 88 showing the drive assembly in an in-use position according to one embodiment of the present invention. [Figure 94] FIG. 94 is a perspective view of a spacer assembly of a drug delivery system according to one embodiment of the present invention. [Figure 95] FIG. 95 is a front view of the spacer assembly of FIG. 94 according to one embodiment of the present invention. [Figure 96] FIG. 96 is a cross-sectional view of the spacer assembly of FIG. 94 according to one embodiment of the present invention. [Figure 97] FIG. 95 is a perspective view of the spacer assembly of FIG. 94 according to one embodiment of the present invention. [Figure 98] FIG. 98 is a perspective view of a fixed spacer of the spacer assembly of FIG. 94 according to one embodiment of the present invention. [Figure 99] FIG. 99 is a perspective view of an adjustable spacer of the spacer assembly of FIG. 94 according to one embodiment of the present invention. [Figure 100] FIG. 100 is a perspective view of a shim of the spacer assembly of FIG. 94 according to one embodiment of the present invention.

[0014] Corresponding reference characters indicate corresponding parts throughout the several views. The illustrations described herein illustrate exemplary aspects of the present disclosure, and such illustrations are not to be construed as limiting the scope of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] The following description is provided to enable one of ordinary skill in the art to make and use the contemplated and described embodiments to practice the invention. However, various modifications, equivalents, variations, and alternatives will be readily apparent to those of ordinary skill in the art. Any and all such modifications, variations, equivalents, and alternatives are intended to fall within the spirit and scope of the invention.

[0016] For purposes of the following description, the terms "upper", "lower", "right", "left", "vertical", "horizontal", "top", "bottom", "lateral", "longitudinal" and their derivatives shall refer to the present invention as illustrated in the drawings. It should be understood, however, that the present invention can assume various alternative modifications unless expressly specified to the contrary. It should also be understood that the specific devices illustrated in the accompanying drawings and described in the following specification are merely exemplary embodiments of the invention. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting.

[0017] 1-16, a drug delivery system 10 according to one embodiment of the present invention includes a drive assembly 12, a reservoir 14, a valve assembly 16, and a needle actuator assembly 18. The drive assembly 12, the reservoir 14, the valve assembly 16, and the needle actuator assembly 18 are at least partially disposed within a housing 20. The housing 20 includes a top portion 22 and a bottom portion 24, although other suitable configurations for the housing 20 may be utilized. In one embodiment, the drug delivery system 10 is an injector device that is worn or secured to a user and configured to deliver a predetermined dose of a drug provided in the reservoir 14 by injection into the user. The system 10 may be utilized to deliver a "bolus injection" in which the drug is delivered within a set time period. The drug may be delivered over a period of up to 45 minutes, although other suitable injection volumes and durations may be utilized. The bolus administration or delivery may be performed with or without specific rate control. The system 10 may deliver the drug to the user at a constant pressure with variable rates. The general operation of system 10 is described below with reference to Figures 1-16, with details of drive assembly 12, needle actuator assembly 18, and other features of system 10 described below in connection with Figures 17-93.

[0018] 1-16, the system 10 is configured to operate via a user's engagement of the actuator button 26, which completes the insertion of a needle 28 of the needle assembly 18 into the user's skin, actuation of the drive assembly 12 to place the needle 28 in fluid communication with the container 14 and expel the fluid or medicament from the container 14, and withdrawal of the needle 28 following injection of the medicament. The general operation of the drug delivery system is shown and described in WO 2013 / 155153 and WO 2014 / 179774, which are incorporated herein by reference in their entireties. The housing 20 of the system 10 includes an indicator window 30 for viewing an indicator device 32 configured to provide an indication to a user regarding the status of the system 10, and a container window 31 for viewing the container 14. The indicator window 30 may be a magnifying lens to provide a clear view of the indicator device 32. The indicator device 32 moves with the needle actuator assembly 18 during use of the system 10 to indicate pre-use, use, and post-use states of the system 10. The indicator device 32 provides a visual indication regarding the status, although other suitable indications, such as audible or tactile, may be provided as alternative or additional indications.

[0019] 4-6, during a pre-use position of the system 10, the container 14 is spaced from the drive assembly 12 and the valve assembly 16, and the needle 28 is in a retracted position. During initial actuation of the system 10, the drive assembly 12 engages the container 14 to pierce a closure 36 of the container 14 and move the container 14 toward the valve assembly 16, which is configured to fluidly communicate the medicament within the container 14 to the needle 28 via a tube (not shown) or other suitable arrangement, as shown in FIGS. 7-9. The drive assembly 12 is configured to engage a stopper 34 of the container 14, which initially moves the entire container 14 into engagement with the valve assembly 16 due to the incompressibility of the fluid or medicament within the container 14. Initial actuation of the system 10 is triggered by engagement of the actuator button 26 by a user, which releases the needle actuator assembly 18 and the drive assembly 12, as described in detail below. During initial actuation, the needle 28 is in a retracted position and is about to move to an extended position for injecting a user of the system 10.

[0020] During the use position of the system 10, the needle 28 is in a position at least partially extended outside the housing 20 with the drive assembly 12 moving the stopper 34 within the container 14 to deliver medicament from the container 14 through the needle 28 to the user, as shown in Figures 10-12. In such a use position, the valve assembly 16 has already pierced the closure 36 of the container 14, placing the container 14 in fluid communication with the needle 28, which also allows the drive assembly 12 to move the stopper 34 relative to the container 14 so that fluid may be dispensed from the container 14. In the post-use position of the system 10, as shown in Figures 13-15, the needle 28 is in a retracted position and engaged with the pad 38 to seal the needle 28 and prevent residual flow of fluid or medicament from the container 14. The container 14 and the valve assembly 16 may be the container 14 and the valve assembly 16 described in International Publication No. WO 2015 / 081337, the entirety of which is incorporated herein by reference.

[0021] 15A-15C, the pad 38 is biased into the needle actuator body 96 as it moves from the use position to the post-use position. Specifically, the pad 38 is received by a pad arm 122 having a cam surface 124 that cooperates with a cam track 126 on the bottom 24 of the housing 20. The pad arm 122 is connected to the needle actuator body 96 via a torsion bar 128. The cam surface 124 is configured to engage the cam track 126 to bias the pad arm 122 downward, thereby allowing the pad 38 to pass under the needle 28 before being biased upwardly against the needle 28. The torsion bar 128 allows the pad arm 122 to rotate about a pivot in the needle actuator body 96. The pad 38 may be press-fit into an opening in the pad arm 122, although other suitable configurations for securing the pad 38 may be utilized.

[0022] 1-33, a drive assembly 12 is shown according to one embodiment of the present invention. As mentioned above, the drive assembly 12 is configured to move the container 14 to pierce the closure 36 of the container 14 and also to move the stopper 34 within the container 14 to dispense a fluid or drug from the container 14. The drive assembly 12 shown in FIGS. 17-33 is configured to engage and cooperate with a spacer assembly 40 that is received by the stopper 34 of the container 14. The spacer assembly 40 includes a spacer 42 and a spacer holder 44. The spacer holder 44 is received by the stopper 34 and the spacer 42 is received by the spacer holder 44. The spacer holder 44 includes a first threaded portion 46 that engages a corresponding threaded portion of the stopper 34, although other suitable configurations may be utilized. The spacer 42 also includes a threaded portion 48 that engages a corresponding second threaded portion 50 of the spacer holder 44 to secure the spacer 42 to the spacer holder 44, although other suitable configurations may be utilized. The drive assembly 12 is configured to dispense a range of predetermined fill volumes of the container 14 while maintaining the functional features of the system 10 described above, including, but not limited to, providing an indication of the status of the system 10 while also minimizing retraction of the needle 28 after completion of administration and abrupt engagement of the stopper 34 by the drive assembly 12. The drive assembly 12 is configured to dispense a plurality of distinct fill volume ranges by utilizing a plurality of sizes of spacers 42. In one embodiment, twelve fill volume ranges and twelve sizes of spacers 42 are provided. In one embodiment, the length of the spacers 42 is varied to accommodate different fill volumes within the container 14. Alternatively, a single size spacer 42 may be utilized with multiple fill volumes accommodated within the container 14 by utilizing multiple shims received by the spacers 42.

[0023] 17-26, the drive assembly 12 includes a first plunger member 52, a second plunger member 54 received by the first plunger member 52, a first biasing member 56, a second biasing member 58, a plunger actuation member 60, and an indexing member 62. The first plunger member 52 is movable from a pre-use position (shown in FIG. 18) to a use position (shown in FIG. 19) to a post-use position (shown in FIG. 20) such that the first plunger member 52 engages the spacer assembly 40 and is configured to move the stopper 34 within the container 14 to dispense the medicament from the container 14. The first plunger member 52 is configured to move axially. The second plunger member 54 and the first plunger member 52 form a nested structure such that the second plunger 54 moves axially after the first plunger member 52 moves a predetermined axial distance. Movement of the first and second plunger members 52, 54 is effected by first and second biasing members 56, 58 which are compression springs, although other suitable configurations for the biasing members 56, 58 may be utilized.

[0024] The first biasing member 56 is received by the second plunger member 54 and is captured between the plunger actuating member 60 (and indexing member 62) and a first spring seat 64 of the second plunger member 54. The second biasing member 58 is located radially inward from the first biasing member 56 and is received by the second plunger member 54. The second biasing member 58 is captured between a second spring seat 66 of the second plunger member 54 and the first plunger member 52. The second biasing member 58 is configured to bias the first plunger member 52 from a pre-use position to a use position and a post-use position toward the container 14. The first biasing member 56 is configured to bias the second plunger member 54 toward the container 14, which in turn biases the first plunger member 52 from a pre-use position to a use position and a post-use position toward the container 14. More specifically, the second biasing member 58 is configured to drive the first plunger member 52 against the spacer assembly 40 or stopper 34 to move the container 14 into engagement with the valve assembly 16, thereby piercing the closure 36 of the container 14 and placing the container 14 in fluid communication with the needle 28. The first biasing member 56 is configured to move the stopper 34 within the container 14 to dispense the medicament within the container 14. The second biasing member 58 has a different spring constant than the first biasing member 56. In particular, the second biasing member 58 is stiffer than the first biasing member 56 to provide a higher force to pierce the closure 36 of the container 14, while the first biasing member 56 provides a lower force for proper dispensing depending on the viscosity of the fluid or medicament within the container 14.

[0025] 17-26, the plunger actuation member 60 includes an annular portion 68 and a spindle portion 70. The plunger actuation member 60 is rotationally movable relative to the first plunger member 52 between a first rotational position and a second rotational position spaced from the first rotational position. The first rotational position may be 15 degrees from the second rotational position, although other suitable positions may be utilized. The annular portion 68 includes a drive surface 72 including a plurality of teeth 74, although other suitable configurations for the drive surface 72 may be utilized. The spindle portion 70 includes an actuator locking surface 76 configured to engage and disengage from a plunger locking surface 78 of the first plunger member 52. The plunger locking surface 78 includes a plurality of projections 80 configured to be received by a plurality of slots or notches 81 defined by the actuator locking surface 76.

[0026] 18 and 23, in a first rotational position of the plunger actuating member 60, the plurality of projections 80 and the plurality of slots or notches 81 are misaligned such that the plunger actuating member 60 is engaged with the first plunger member 52 to prevent movement of the first and second plunger members 52, 54 with the first and second biasing members 56, 58 biasing the first and second plunger members 52, 54 away from the plunger actuating member 60. As shown in FIGS. 19 and 24, in a second rotational position of the plunger actuating member 60, the plurality of projections 80 and the plurality of slots or notches 81 are aligned with one another such that the plunger actuating member 60 is disengaged from the first plunger member 52 to permit movement of the first and second plunger members 52, 54, thereby initiating the dispensing process from the container 14.

[0027] 7 and 33, the drive surface 72 of the plunger actuation member 60 is configured to be engaged by a portion of the needle actuator assembly 18. After engagement of the actuator button 26 and release of the needle actuator assembly 18, the needle actuator assembly 18 moves within the housing 20 from a pre-use position to a use position and a post-use position, as described in more detail below. During the initial movement of the needle actuator assembly 18, the portion of the needle actuator assembly 18 engages the drive surface 72 of the plunger actuation member 60 to move the plunger actuation member 60 from a first rotational position to a second rotational position. As shown in FIG. 33, an angled blade portion 82 of the needle actuator assembly 18 engages the drive surface 72 of the plunger actuation member 60 to cause rotation of the plunger actuation member 60.

[0028] 11, 13 and 26, the second plunger member 52 includes a plurality of coding protrusions 84 having a preselected one of the plurality of coding protrusions 84 configured to engage a limiting member 86 of the system 10. As described in more detail below, the limiting member 86 cooperates with the needle actuator assembly 18 to limit movement of the needle actuator assembly 18 from a use position to a post-use position until a predetermined end-of-dose position of the stopper 34 is achieved. In one embodiment, the limiting member 86 is configured to limit axial movement of the needle actuator assembly 18 from the use position via engagement between the limiting member 86 and a portion of the needle actuator assembly 18. Such engagement between the limiting member 86 and the needle actuator assembly 18 is released by rotation of the limiting member 86 when the stopper 34 reaches the end-of-dose position. During the use position of the needle actuator assembly 18, the restricting member 86 is rotationally biased with rotation of the restricting member 86 prevented via engagement between the restricting member 86 and one of the plurality of coded protrusions 84 of the second plunger member 54. The plurality of coded protrusions 84 may be axial ribs of various lengths, although other suitable configurations may be utilized. Each of the coded protrusions 84 defines a point at which the restricting member 86 may rotate, thereby releasing the needle actuator assembly 18. The smooth portion of the second plunger member 52 may provide an additional "code" for determining when the system 10 transitions to the end-of-dose position.

[0029] As discussed above, indicator device 32 moves with the different portions of indicator device 32 visible through indicator window 30 as system 10 moves from pre-use, use, and post-use or end-of-dosing positions. More specifically, indicator device 32 engages a portion of restricting member 86 and moves with restricting member 86 through the various stages of system 10 to provide an indication to the user regarding the status of system 10.

[0030] During assembly of the system 10, a dose of the container 14 is matched to a particular spacer 42 having a set length, and a corresponding one of the plurality of coded projections 84 is aligned with the restricting member 86. Thus, as described above, the container 14 may be provided with a plurality of doses, with each volume corresponding to a particular spacer 42 and coded projection 84. In this manner, even with different doses, the system 10 is configured to inject the needle 28 into a user to deliver a dose of medication from the container 14, retract the injection needle 28 after administration is complete, and provide an indication of the status of the system 10 while minimizing abrupt engagement of the stopper 34 by the drive assembly 12. In particular, the size of the stopper 34 may be selected to minimize the distance between the first plunger member 52 and the spacer assembly 40, without requiring the use of damping.

[0031] 27-33, a drive assembly 12A according to a further embodiment of the present invention is shown. The drive assembly 12A shown in FIGS. 27-33 is similar to the drive assembly 12 shown in FIGS. 17-26 and described above, and operates in a similar manner. In the drive assembly of FIGS. 27-33, however, the first plunger member 52 is received by and extends from the second plunger member 54 during axial movement from the pre-use position to the use position. Additionally, the first plunger member 52 includes an extension portion 88 configured to engage the second plunger member 54 after the first plunger member 52 has moved a predetermined axial distance such that the first plunger member 52 and the second plunger member 54 move together. The first and second biasing members 56, 58 engage and act on the first and second plunger members 52, 54 in the same manner as the drive assembly 12 of Figures 17-26.

[0032] 27-32, an indexing member 62 includes a plurality of ratchet teeth 90 disposed about the first and second plunger members 52, 54 and configured to engage a flexible tab 92 located on the bottom 24 of the housing 20. When the drive assembly 12, 12A is attached to the bottom 24 of the housing 20, engagement of the ratchet teeth 90 of the indexing member 62 with the flexible tab 92 of the housing 20 results in unidirectional rotation of the indexing member 62. The indexing member 62 is configured to rotate one of the coded projections 84 of the second plunger member 52 into alignment with the limiting member 86 based on the dose and the size of the spacer 42 as described above. The indexing member 62 can provide the drive assembly 12, 12A with 24 rotational positions, 12 of which can have unique dose values ​​associated therewith.

[0033] 1-16 and 34-40B, a needle actuator assembly 18 according to one embodiment of the present invention is shown. The needle actuator assembly 18 includes a needle actuator body 96 having a guide surface 98, a needle shuttle 102 having a cam surface 104, and a needle 28 that is received by the needle shuttle 102 and configured for fluid communication with the container 14 as described above. The needle actuator body 96 is generally rectangular with the guide surface 98 projecting radially inward. The needle shuttle 102 is received within the needle actuator body 96. As described above, the needle actuator body 96 is movable within the housing 20 from a pre-use position (shown in FIGS. 4-6), to an initial actuated position (FIGS. 7-9), a use position (FIGS. 10-12), and a post-use position (FIGS. 13-15). The needle actuator body 96 is biased from a pre-use position to a post-use position via a tension spring 106, although other suitable biasing arrangements may be utilized. The needle actuator body 96 is released upon engagement of the actuator button 26 and is free to move from the pre-use position to the use position, as will be described in more detail below. The needle actuator body 96 moves from the use position to the post-use position following rotation of the restricting member 86, as described above in connection with Figures 17-33.

[0034] 34-40B, the needle shuttle 102 is movable along a vertical axis between a retracted position in which the needle 28 is positioned within the housing 20 and an extended position in which at least a portion of the needle 28 extends outside the housing 20. The needle shuttle 102 is configured to move between the retracted and extended positions by engagement between a guide surface 98 of the needle actuator 96 and a cam surface 104 of the needle shuttle 102. The cam surface 104 is provided by first and second cam members 108, 110, with the first cam member 108 spaced apart from the second cam member 110. The housing 20 includes a guide post 112 having a recess configured to receive a T-shaped protrusion 114 on the needle shuttle 102, although other shapes and configurations for the guide post 112 and the T-shaped protrusion 114 may be utilized. The needle shuttle 102 moves along the guide post 112 between the retracted and extended positions. The guide posts 112 are straight and extend generally perpendicularly from the housing 20, although other suitable arrangements may be utilized. The guide surfaces 98 of the needle actuator body 96 are non-linear and each include a first surface 116 and a second surface 118 positioned opposite the first surface 116.

[0035] As discussed below, the guide surface 98 of the needle actuator body 96 cooperates with the cam members 108, 110 of the needle shuttle 102 to move the needle shuttle 102 vertically between the retracted and extended positions as the needle actuator body 96 moves axially from the pre-use position to the post-use position. The needle shuttle 102 also includes a shuttle biasing member 120 configured to engage the housing 20 or the actuator button 26. In particular, the shuttle biasing member 120 engages the housing 20 or the actuator button 26 and provides a biasing force as the needle actuator body 96 is transitioning from the use position to the post-use position. When the needle actuator body 96 is fully transitioned to the post-use position, the cam members 108, 110 of the needle shuttle 102 disengage from the guide surface 98 of the needle actuator body 96, and the shuttle biasing member 120 biases the needle shuttle 102 downward such that the needle 28 engages the pad 38, as described above. 1-16, the pad 38 may also bias the needle shuttle 102 against the needle 28 rather than biasing it downward via the shuttle biasing member 120. The needle actuator body 96 may interact with the actuator button 26 to prevent the actuator button 26 from popping back up until a post-use position is reached, as will be described in more detail below.

[0036] 37A-40B, in the pre-use position (FIG. 37A), the needle shuttle 102 is in a retracted position with the cam members 108, 110 spaced apart from the guide surface 98 of the needle actuator body 96. As the needle actuator body 96 moves to the use position (FIGS. 37B and 38A), the second cam member 110 of the needle shuttle 102 engages the second side 118 of the guide surface 98, moving the needle shuttle 102 from the retracted position to the extended position. During transition of the needle actuator body 96 from the use position to the post-use position (FIG. 37C), the first cam member 108 of the needle shuttle 102 engages the first side 116 of the guide surface 98, moving the needle shuttle 102 from the second position to the first position. After the needle actuator body 96 is fully transitioned to the post-use position (FIGS. 37D and 38B), the shuttle biasing member 120 biases the needle shuttle 102 downward as the cam members 108, 110 disengage from the guide surface 98 of the needle actuator body 96, with the needle 28 engaged with the pad 38. The transition of the needle actuator body 96 and the corresponding position of the needle shuttle 102 are also shown in FIGS. 39-40B. The interaction between the actuator button 26 and the needle actuator body 96 is described in detail in connection with FIGS. 65A-67. Referring to FIGS. 41-64, a drug delivery system 200 according to a further embodiment is shown. The system 200 includes a housing 202 having an upper housing 204 and a lower housing 206. The housing has a proximal end 205 and a distal end 207. The upper housing 204 has a status viewport 208 to allow a user to view the operating status of the system 200. The system 200 also includes a valve assembly 212 and a tube 214 that fluidly connects the valve assembly 212 to a patient needle 215 disposed at the proximal end of a needle arm 216. A spring 218 biases a needle actuator 220 in a distal direction.

[0037] 42-46, the system 200 additionally includes a container, i.e., a medicament container 222, with a movably disposed stopper 224, although the stopper 224 has been omitted from the various views to aid in clarity. Preferably, the distal end of the medicament container 222 has a septum assembly 228 that is spaced from the valve assembly 212 prior to actuation of the device 222, as best shown in FIG.

[0038] For manufacturing purposes, it is often desirable to use one size of drug container, even when multiple fill volumes or doses are intended for use with the container. In such cases, different fill volumes will result in different stopper locations when the drug container is filled. To accommodate such different stopper locations as well as to accommodate manufacturing variations in the stopper, embodiments of the present invention include a custom, or customized, spacer 226 disposed at the proximal end of the container 222 adjacent the stopper 224. In other words, the custom customized spacer 226 provides an option to allow for a range of predetermined fill volumes set by the manufacturer through the selection of different spacers 226, reducing or eliminating the need for assembly configuration work. The size of the spacer 226 may be adapted to account for underfill volumes of the container 222 and provide a consistent bearing surface at the proximal end of the container.

[0039] Spacer 226 is selected from a number of different sized spacers 226 to occupy the space from the proximal end of stopper 224 to the proximal end of container 222. According to one embodiment, spacer 226 is selected to be substantially flush with the proximal end of container 222, as shown in Figures 45-47. Additionally, according to one embodiment, spacer 226 has a "bowler hat" shape that includes a central column 230 and end flanges 232, as best shown in Figure 45.

[0040] 44-47, the system 200 also includes a drive assembly 234 for displacing the container 222 and dispensing the medicament from the container 222 to establish a fluid connection between the container 222 and the patient needle 215. More specifically, the drive assembly 234 includes an inner spring 236 disposed within a central plunger 238, an outer plunger 240, an outer spring 242 disposed between the central plunger 238 and the outer plunger 240, a telescoping member 244, and a release gate 246.

[0041] Preferably, the inner spring 236 has a greater spring constant than the outer spring 242 and is therefore stronger or stiffer than the outer spring 242. The inner spring 236 is disposed inside the central plunger 238 and, following actuation of the device, presses between a spring flange 248 of the lower housing (best shown in FIG. 46) and the central plunger 238 which directly bears against the proximal end of the spacer 226. The outer spring 242 is disposed inside the outer plunger 240 and presses between a proximal outer flange 250 of the central plunger 238 and a distal inner flange 252 of the outer plunger 240. In this manner, the inner and outer springs 236 and 242 are nested, providing a more compact drive assembly (and therefore a more compact system 200) than would be possible using a single spring.

[0042] According to one embodiment, the inner spring 236 acts only to displace the reservoir 222 to establish a fluid connection with the patient needle 215, and the outer spring 242 acts only to subsequently dispense the medicament from the reservoir 222. According to another embodiment, the inner spring 236 acts to displace the reservoir 222 to establish a fluid connection with the patient needle 215 and also to begin dispensing the medicament from the reservoir 222, and the outer spring 242 acts to complete the dispensing of the medicament. In a further embodiment, the inner spring 236 causes the initial piercing of the reservoir 222, with the outer spring 242 completing the piercing and dispensing of the medicament from the reservoir 222.

[0043] As shown in FIGS. 44-47, and as described in more detail below, the outer plunger 240 includes a pair of proximal flanges or feet 254, each having a ramped surface that interacts with a corresponding ramped surface (or surfaces) of the release gate to retain and subsequently release the power module following actuation of the device 200.

[0044] As best seen in FIGS. 46 and 47, when initially assembled, the container 222 is spaced from the drive assembly 234 and the valve assembly 212. A lateral flange 256 of the needle actuator 220 axially retains the drug container 222, and the needle actuator 220 prevents the release gate 246 from moving laterally. According to one embodiment, a spring (not shown) biases the needle actuator 220 distally, but the activation button 210 (and / or its associated assembly) prevents distal displacement of the needle actuator 220 prior to actuation of the device 200. A status bar 258 is disposed on the needle actuator 220 and has a top surface that is visible through the status viewport 208. According to one embodiment, the top surface of the status bar has multiple colors or patterns, and a first color or pattern, such as yellow, is visible through the status viewport 208 when the device is in a pre-actuated state.

[0045] 48-52 are top views of the system 200 illustrating operation of the system 200 during actuation and subsequent events. In FIG. 47, the user slides the activation button 210 proximally, which then moves the button 210 vertically into the housing 202, thereby freeing the needle actuator 220 to displace distally under the influence of a spring (omitted for clarity). As shown in FIG. 49, as the needle actuator is displaced distally, the track 260 of the needle actuator 220 interacts with the lateral boss 262 of the needle arm 216 to insert the patient needle 215. Preferably, at this stage, the drive assembly 234 is not yet released, since the proximal end of the needle actuator 220 has not yet cleared the release gate 246. However, the lateral flange 256 has been displaced distally, and thus the container 222 is unconstrained.

[0046] 50 and 51, continuing distal movement causes the proximal end of the needle actuator 220 to clear the release gate 246 (thereby releasing the drive assembly 234). The needle actuator 220 momentarily rests against a feature of the rotatable release flipper 264, forcing the release flipper 264 against the outrigger 266 (best seen in FIGS. 44 and 59) of the telescoping member 244. The needle actuator 220 remains in this position until the medication has been dispensed. In this position, preferably the second color or pattern of the status bar 258, e.g., green, is visible through the status viewport 208.

[0047] At this stage, the force of springs 236 and 242 and the interaction of the ramped surface of proximal flange or foot 254 with the corresponding ramped surface (or surfaces) of release gate 246 cause a lateral displacement of release gate 246, thereby freeing outer plunger 240 from the constraint of its interaction with release gate 246. Up to this point, outer plunger 240 has continued to constrain central plunger 238.

[0048] 52 and 53 (inner spring 236 is omitted in FIG. 52 for clarity), stiff inner spring 236 drives central plunger 238 distally into contact with spacer 226. Because drug reservoir 222 is filled with a substantially incompressible fluid, continued distal displacement of central plunger 238 displaces spacer 226, stopper 224, and reservoir 222 distally relative to housing 202. This distal displacement causes septum assembly 228 to be pierced by valve assembly 212, establishing fluid communication between reservoir 222 and patient needle 215. Central plunger 238 moves distally until its proximal exterior flange 250 (best seen in FIG. 59) contacts a flange on lower housing 206, thereby limiting "puncture travel." Preferably, another flange on the lower housing 206 and / or a side flange 256 on the needle actuator 220 limits distal movement of the reservoir 222 .

[0049] Thereafter, because the inner spring 236 can no longer displace the central plunger 238 distally, the light outer spring 242 displaces the outer plunger 240 distally relative to the central plunger 238 and into contact with the distal flange 232 of the spacer 226 as shown in Figures 54 and 55. As will be described in more detail below, preferably the contact between the outer plunger 240 and the spacer 226 is damped to minimize impact forces. Further extension of the outer spring 242 displaces the outer plunger 240 distally, dispensing the medicament.

[0050] 56 and 57, as the outer spring 242 continues to expand and displace the outer plunger 240 distally, at a given distal displacement of the outer plunger 240 relative to the telescoping member 244, an exterior feature or flange 268 of the outer plunger 240 interacts with an interior distal feature or flange 270 of the telescoping member 244 and "picks up" the telescoping member 244. This ensures that further distal displacement of the outer plunger 240 causes a corresponding distal displacement of the telescoping member 244. This pair of distal displacements continues until the end of the drug delivery.

[0051] As previously described, the outrigger 266 is disposed on the telescoping member 244. The axial length of the outrigger and the distal movement of the telescoping member 244 control the timing of disengagement of the outrigger 266 with the release flipper 264. As shown in Figs. 58 and 59, at the end of drug delivery, the proximal end of the outrigger 266 bypasses the release flipper 264. This causes the release flipper 264 to rotate out of engagement with the needle actuator 220 (Fig. 60), which allows the actuator 220 to continue its distal displacement and withdraw the patient needle 215 (Fig. 61). At this stage, a different color or pattern of the status bar 258, e.g., red, is visible through the viewing port 208, indicating that the device 200 has completed its operation.

[0052] As previously mentioned, the contact between the outer plunger 240 and the spacer 226 is preferably damped to minimize impact forces, as shown in Figures 62 and 63. The highest level of energy dissipation is desired for an unfilled syringe containing a viscous fluid, since the outer spring 242 may be stiffer to provide the desired dispense rate. The lowest level of energy dissipation is desired for a fully filled syringe containing a low viscosity fluid, since the outer spring may be less stiff to provide the desired dispense rate. Various methods may be used to adjust the damping level, such as air damping or closed bubble damping.

[0053] As another method of damping impact forces, FIG. 64 shows an embodiment of a spacer 226 in which one or more axial interference ribs 272 are arranged circumferentially around the central column 230 of the spacer 226. In this embodiment, the outer plunger 240 must be driven past the interference ribs 272, which provide frictional resistance to distal displacement of the outer plunger 240 relative to the spacer 226. The frictional force generated by the interference between the interference ribs 272 and the outer plunger 240 is independent of plunger speed. Preferably, the frictional force does not exceed the minimum distribution spring load to avoid stalling the weak spring. The interference may be adjusted to provide a desired level of frictional resistance. There may be different dimensioning (axial and / or radial) of the interference ribs 272 for different fluid viscosities. This can mean bespoke or custom spacers for each viscosity and fill level combination or number of springs required for a viscosity range, with multiple corrugated positions so that the spacer may be set to a specific position for a particular modular spring (whose position is tuned for interference / damping for that particular spring load / viscosity scenario).

[0054] 65A-69, an actuator button device 280 for actuating the system 10 according to one embodiment of the present invention is shown. The actuator button device 280 includes an actuator button 26, a button spring 284, and a needle actuator body 286. The needle actuator body 286 is similar to the needle actuator bodies 96, 220 described above and is configured to move within the housing 20 to transition the needle shuttle 102 or needle 28 between a retracted position and an extended position. As shown in FIG. 69, the actuator button 26 includes a user interface portion 288 for interacting with a user. Preferably, the user interface portion 288 is approximately 22 mm in length and approximately 10 mm in width, although other suitable dimensions may be utilized. The actuator button 26 includes two pairs of lockout arms 290, 292 that interact with button contact surfaces 294, 296 of the needle actuator body 286 prior to activation of the device to prevent the needle actuator body 286 from swinging upward. As shown in Figure 65H, the overlap between the needle actuator body 286 and the housing 20 prevents premature actuation. Referring to Figure 66, the button spring 284 includes a cantilevered central spring arm 302 surrounded by a first bearing surface 298 and a second bearing surface 300 spaced from the first bearing surface 298 and a pair of outer arms 304 connected by the first bearing surface 298.

[0055] The actuation button arrangement 280 is configured to provide one or more of the following features, which are discussed in more detail below: unidirectional axial displacement or sliding of the actuator button 26; lateral movement of the actuator button 26 (raised and recessed positions) where the actuator button 26 remains depressed while the needle actuator body 286 is in the use position; and locking out of the actuator button 26 in a post-use position of the needle actuator body 286 such that the button 26 is in a raised position and cannot be depressed by the user.

[0056] To activate the system 10 using the actuator button 26, the user first slides the user interface portion 288 in a first axial direction shown as being on the right in FIGS. 65G and 65H. The user may be required to slide the user interface portion 288 approximately 10 mm or approximately 8 mm, although other suitable distances may be utilized. Moving the actuator button 26 axially moves the lockout arms 290, 292, clearing the button contact surfaces 294, 296 of the needle actuator body 286 and allowing the actuator button 26 to move from a raised position (first position) to a depressed position (second position).

[0057] As the user slides the user interface portion 288 in a distal direction, the central spring arm 302 of the button spring 284 rides over the bearing surface of the spring arm 306 on the housing 20 while the first and second bearing surfaces 298, 300 engage the first and second bearing beveled surfaces 308, 310 of the housing 20. The force of the button spring 284 is balanced by the engagement with the spring arm bearing surface 306 and the first and second bearing beveled surfaces 308, 310 to provide smooth axial displacement or sliding of the actuator button 26.

[0058] When the actuator button 26 and button spring 284 reach the end of their axial sliding travel, the central spring arm 302 and first bearing surface 298 pass the ends of their respective stops 312, 314 to prevent the actuator button 26 from sliding back to its original position, as shown in FIG. 65H. Furthermore, when the actuator button 26 and button spring 284 reach the end of their axial sliding travel, the user engages the user interface portion 288 to move the actuator button 26 downward to its depressed position. The actuator button 26 is depressed approximately 2 mm, and the minimum force required to depress the actuator button 26 is approximately 3 N, and most preferably approximately 2.8 N, although other suitable distances and minimum forces may be utilized.

[0059] When a user presses the user interface portion 288 shown in Figures 65A and 65B, the actuator button 26 rotates the needle actuator body 286 to release the needle actuator body 286, thereby allowing the needle actuator body 286 to move from a pre-use position to a use position. As the needle actuator body 286 moves to the use position, as shown in Figure 65B, the lockout arms 290, 292 move along the underside of the button contact surfaces 294, 296 to prevent the actuator button 26 from bouncing upward. After the medication is delivered and the needle actuator body 286 is transitioning from the use position to the post-use position, as shown in Figure 65C, the lockout arms 290, 292 disengage from the button contact surfaces 294, 296 to allow the actuator button 26 to bounce under the influence of the button spring 284. When the needle actuator body 286 is fully transitioned to the post-use position, as shown in Figure 65D, the actuator button 26 has completed moving from the depressed position to the raised position due to the biasing force of the button spring 284. When the needle actuator body 286 is in the post-use position, the spring arm 316 of the needle actuator body 286 engages the actuator button 26 to prevent the actuator button 26 from moving to the depressed position, while axial movement is limited by engagement of the spring arm 302 with the stops 312, 314. Thus, to provide a clear indication between a used and unused system, the actuator button 26 is locked after drug delivery is completed.

[0060] Additionally, if the user holds down the actuator button 26 during administration of medication, the proper dosage and needle retraction will still be completed, but the actuator button 26 will not return to the raised position until the button 26 is released.

[0061] In one embodiment, the button spring 284 is made from plastic. The button spring 284 may alternatively be a pressed metal spring, although any other suitable material may be utilized.

[0062] 68A-68G, rather than providing a separate actuator button 26 and button spring 284, the spring may be integral with the button 26. More specifically, an actuator button 320 according to a further embodiment of the present invention includes an integral spring arm 322. The actuator button 320 also includes a lockout arm 324, a retention arm 326, and a rear pivot 328. As shown in FIGS. 68D and 68E, the spring arm 322 engages a protrusion 330 on the top 22 of the housing 20. During transition of the system 10 from the pre-use position to the use position, the spring arm 322 slides past a detent on the protrusion 330 providing an axial spring force. An end of the spring arm 322 engages a portion of the top 22 of the housing 20 and provides a vertical spring force as the spring arm 322 flexes. The actuator button 320 is configured for fluid movement between a sliding movement and a depressed movement of the button 320, even though two separate movements occur, similar to the operation of the button 26 described above. During the transition between the pre-use and use positions, the button 320 pivots about a rear pivot 328 with the retaining arm 326 engaging a portion of the needle actuator body 286, thereby maintaining the depressed position of the button 320 until the end-of-dose position is reached in a manner similar to the actuator button 26. The lockout arm 324 flexes inwardly and engages a portion of the needle actuator body 286 as the needle actuator body 286 moves to the end-of-dose position, thereby preventing further movement of the actuator button 320 in a manner similar to the actuator button 26 described above.

[0063] Aspects of the present invention provide improvements over previous button designs. For example, the activation button device 280 provides multiple surfaces that hold the needle actuator body 286 in place against the needle actuator spring 106 prior to actuation, thereby reducing the likelihood of premature actuation during a drop shock. The activation button device 280 physically prevents the needle actuator body 286 from moving prior to actuation by holding the surfaces in an angled (locked) position such that there is no room for separation and pre-actuation.

[0064] Additionally, the button sliding force of the actuation button device 280 is more precisely controlled by utilizing a curved arm rather than using a simple bumpy detent. This allows for a longer sliding stroke of the button 26 with better force control resulting in a more ergonomically effective design. Furthermore, the actuation button device 280 causes the button 26 to push back at the end of an injection, providing the user with additional visual, audible and tactile feedback that drug delivery is complete.

[0065] According to one embodiment, the fluid delivery volume of the system 10 is determined by the end position of the plunger relative to a point within the housing, regardless of the actual fill volume, the inside diameter of the container, and the start position and length of the stopper. Variations in dosing accuracy can be significant as the tolerances for the factors mentioned above can be very large. Aspects of the present invention allow for some or all of these tolerances to be removed from the dosing equation, resulting in more accurate and less variable doses of medication.

[0066] 70A-70G, a spacer assembly 400 for use in conjunction with a drive assembly according to one embodiment of the present invention is shown.

[0067] The elements in the chain of tolerances in the stopper spacer assembly 400 include the thickness (A) of the flange 402 of the inner plunger 404, the internal length (B) of the outer plunger 406 between the inner proximal end 408 and the inner shoulder 410, and the initial offset distance (C1) between the inner plunger flange 402 and the inner proximal end 408 of the outer plunger. This initial offset distance (C1) is preferably greater than the gap distance (C2) between the outer plunger 406 and the proximal end of the drug barrel 412. The chain of tolerances in the stopper spacer assembly 400 also includes the diameter (D) of the inner barrel. Once assembled, the stopper spacer 414 and outer plunger 406 are unique to a given drug volume.

[0068] Figures 70B-70G show the operation of the stopper spacer assembly 400. As shown in Figure 70B, when the system is actuated, both the inner plunger 404 and the outer plunger 406 are released. The outer spring 416 pushes the outer plunger 406 into the barrel 412, compressing the dampening material 18 and pushing against the inner spring 420. The stopper 422 has not yet moved relative to the barrel 412 due to the fluid column of the drug.

[0069] 70C, the outer spring 416 displaces the outer plunger 406 and barrel 412 distally, opening a valve (not shown) at the distal end of the barrel 412 and establishing fluid communication with the needle (not shown). Due to the incompressibility of the liquid drug, the stopper 422 cannot be displaced relative to the barrel 412 until the valve is opened and a fluid path is established to the patient needle.

[0070] Subsequently, as shown in Figures 70D and 70E, the inner spring 420 displaces the inner plunger 404, the stopper spacer 414 and the stopper 422 to dispense the fluid.

[0071] FIG. 70F shows the end of drug delivery when the proximal flange 402 of the inner plunger 404 contacts the inner shoulder 410 of the outer plunger 406, thereby stopping movement of the inner plunger 404 (and stopper spacer 414 and stopper 422) relative to the drug barrel 212 and stopping the flow of drug.

[0072] According to one embodiment, as shown in FIG. 70G, cessation of displacement of the inner plunger 404 relative to the drug barrel 412 triggers an end-of-dose indicator for the system.

[0073] 71 and 72, the collapsible spacer assembly 430 includes a front spacer portion 432 secured to a stopper 434, an inner plunger 436, a rear spacer portion 438, and a rotational shuttle 440. The inner plunger 436 can translate relative to the front spacer portion 432, but cannot rotate relative to the front spacer portion 432. Similarly, the rear spacer portion 438 can move axially relative to the front spacer portion 432, but does not rotate relative to the front spacer portion 432. As will be described in more detail below, the rotational shuttle 440 first rotates and then translates.

[0074] According to one embodiment, the front spacer portion 432 is fixedly secured to the stopper 434. Those skilled in the art will appreciate that many methods may be employed to secure the front spacer portion 432 to the stopper 434, such as, for example, adhesives, mechanical fasteners, or any other suitable arrangement. Preferably, the front spacer portion 432 includes threads that engage mating threads in the stopper 434.

[0075] When the stopper spacer assembly 430 is threaded onto the stopper 434, an axial load is applied through the access opening 442 in the rear spacer portion 438. This force can be used to push the stopper 434 forward, exerting pressure on the fluid drug. This pressure causes the front (distal) face of the stopper 434 to deflect and push in a proximal direction, forcing the rear spacer portion 438 back and rotating the rotating shuttle to the "as assembled" state. In other words, when the drug barrel is filled with drug and the plunger of the system exerts an axial force on the drug through the spacer assembly 430, the distal face of the stopper 434 is deformed by the pressure of the drug. During drug delivery, pressure is applied by the drive assembly (through the plunger) to the rear spacer portion 438, which in turn exerts a rotational torque on the rotating shuttle 440 through the helical surface 444 of the rear spacer portion 438. However, deformation of the stopper from the drug exerts a rearward or proximal force on the internal plunger 436, preventing rotation of the rotatable shuttle 440.

[0076] According to one embodiment, the axial reaction load on the inner plunger 436 can be increased by increasing the length of the inner plunger 436 .

[0077] 73, once drug delivery is complete, pressure on the stopper 434 is reduced, thereby allowing the distal end of the inner plunger 436 to displace distally. This distal displacement allows the rotating shuttle 440 to rotate. Continuing axial force applied by the drive assembly rotates and displaces the rotating shuttle 440 distally due to the interaction of the helical surface 444 of the rear spacer portion 438 with the corresponding cam surface arms 446 of the rotating shuttle 440. According to one embodiment, this final movement of the rotating shuttle 440 causes the drive assembly to retract the needle.

[0078] 74 and 75, a limiting member 452 according to one embodiment of the present invention is positioned with the drive assembly. The limiting member 452 governs the timing of the final displacement of the needle actuator body 96, 220 after completion of drug delivery. The limiting member 452 is free to float instead of rotating around a fixed member. Once the plunger is sufficiently displaced distally into the gap to align with the limiting member 452 (as shown in Figs. 74 and 75), the limiting member 452 displaces laterally into the gap due to the spring force of the needle actuator 96, 220 and the rear sloped surface 454 (best shown in Fig. 75) of the arm of the limiting member 174 engaging the needle actuator body. Once the limiting member no longer holds the needle actuator body 96, 220, the needle actuator body 96, 220 is free to complete its axial movement to the post-use position. Additionally, as shown in FIG. 75, the restrictor member 452 is biased against the rear of the barrel portion of the container 14, which minimizes the tolerance chains of the various components and improves dosing accuracy.

[0079] 76-78, a spacer assembly 460 according to a further embodiment of the present invention is shown. The spacer assembly 460 shown in Figures 76-78 allows for elimination of the effects of built-in manufacturing tolerances through adjustment of the spacer assembly, thereby allowing each system to inject the same amount of drug.

[0080] 77, the spacer assembly 460 includes a stopper 462 and a stopper spacer 464. The stopper spacer 464 includes a fixed spacer piece, i.e., a fixed spacer 466, which is fixedly connected to the stopper 462, and an adjustable spacer piece, i.e., an adjustable spacer 468, which is rotatably displaceable in one direction relative to the fixed spacer 466.

[0081] Those skilled in the art will appreciate that many methods may be used to secure the fixed spacer 466 to the stopper 462, such as, for example, adhesives, mechanical fasteners, or any other suitable arrangement. Preferably, the fixed spacer 466 includes one or more external threads that engage with one or more mating threads in the stopper 462. According to one embodiment, the adjustable spacer 468 has a distal stem having external threads 470. The distal stem threads 470 engage internal threads 472 of the fixed spacer 466 to rotate and control the axial displacement of the adjustable spacer 468 relative to the fixed spacer 466 (best seen in FIG. 78 ).

[0082] 76 and 77, the fixed spacer 466 includes radially spaced detents 474, and the adjustable spacer 468 includes a spring detent arm 476. The free end of the spring detent arm 476, which engages a selected one of the detents 474 to prevent rotational and axial displacement of the adjustable spacer 468 toward the fixed spacer 466, is shaped to pass over the detents 474 in one direction, thereby allowing rotational and proximal axial displacement of the adjustable spacer 468 away from the fixed spacer 466.

[0083] The adjustable spacer 468 may be adjusted relative to the fixed spacer 466 to provide a consistent axial length of the stopper assembly 460 despite variations in stopper and container dimensions.

[0084] As shown in FIG. 78, once the container is filled, an axial load, such as that which would be encountered when installed in the system 10, 200, is applied to the adjustable spacer 468 (and thus the fixed spacer 466 and the stopper 462). When the axial load is applied, the adjustable spacer 468 may be retracted proximally to ensure a consistent gap 478 between the proximal end of the drug barrel 480 and the proximal face of the adjustable spacer 468, thereby accounting for deformation of the drug barrel glass and compressibility of trapped air. In other words, the spacer assembly 460 allows the adjustable spacer 468 to have a predetermined set position relative to the container 14, independent of deformation of the container 14 and the length of the stopper. Thus, the starting position of the spacer assembly 460 is a predetermined distance from the container 14, and the ending position of the spacer assembly 460 is also a predetermined distance from the container 14, such that the travel of the stopper 462 is defined by the effective length of the plungers 52, 54 of the drive assembly 12.

[0085] 79 and 80, a base column 482 and a cap 484 of a self-adjusting spacer 486 according to one aspect of the present invention are shown. The base column 482 includes a base portion 488 and an axially extending column 490. According to one embodiment, the base column 482 includes a plurality of column-like projections 491, each of which has a plurality of ratchet teeth 492 disposed on a proximal portion thereof. A locking barb 493 is disposed at a proximal end of each of the plurality of ratchet teeth 492. The cap 484 is hollow, and a distal end of the cap 484 includes one or more axial springs 494. According to one aspect, the axial springs 494 are curved cantilever arms formed during molding of the cap 484. According to another aspect, a separate biasing member, such as a compression spring, may be used with the self-adjusting spacer 486. When assembled with base column 482, spring 494 engages base portion 488 and maintains an initial spacing between base column 482 and cap 484. According to one embodiment, spring 494 is omitted. Cap 484 also includes a plurality of flexible cantilever arms or tabs 496, each having a free proximal portion with a plurality of internal ratchet teeth 497. The proximal end of each flexible tab 496 includes a foot 498.

[0086] 81B shows the self-adjusting spacer cap deployed within a proximal recess of a stopper 494 at the proximal portion of the drug barrel. A base column 482 is assembled to the hollow cap 484 with a base portion 488 engaging the stopper 494 and a foot 498 disposed outside the proximal end of the barrel.

[0087] In operation, as shown in Figures 81A and 81B, the cap 484 is displaced distally relative to the base column 482 (as well as the stopper 494 and barrel) until the proximal end of the cap 484 is flush with the end of the drug barrel. This movement causes the foot 498 to engage the inner surface of the barrel and displace radially inward, thereby urging the ratchet teeth 492 into locking engagement with the ratchet teeth 497. The locking barb 493, the engagement of the ratchet teeth 492 and 497, and the engagement of the foot 498 with the inner surface of the barrel prevent displacement of the cap 484 relative to the base column 482. Thus, the automatically adjusting spacer 486 can accommodate differences in stopper, barrel diameter, and drug load to automatically provide a bearing surface that flattens the proximal end of the drug barrel.

[0088] One aspect of the invention is a spacer assembly 486 that is positioned relative to the stopper in the container in the system. The design of the spacer is such that its effective length can be adjusted to allow for administration of a precise amount of medication. The length adjustment is intended to compensate for manufacturing tolerances in the container, the fill volume, and especially the length of the stopper, and can add up to 1 / 3 of the variation in the dose using a non-adjustable spacer. The length of the spacer can be adjusted by several techniques depending on the particular embodiment. The length of the spacer can be self-adjusting based on its position to the rear of the container, can be adjusted by the assembly machine during final assembly to the main container subassembly, or adjusted as a subassembly prior to filling that can be an integral part of the stopper. The adjustable spacer 486 allows for more precise injection of the amount of fluid compared to a non-adjustable stopper.

[0089] 82-87, there is shown a drive assembly 500 of a drug delivery system according to one embodiment of the present invention. The drive assembly 500 includes an activation button 506, a reservoir 508, a needle actuator assembly 510, a deactivation body or flipper 512, a lead screw 514, and a plunger 516. The lead screw includes a drum portion 518 having radially projecting external vanes 520, and includes a threaded portion 522, as best shown in FIGS. 84 and 85 and will now be described in more detail. Prior to actuation, one end 513 of the deactivation body 512 is engaged with one of the vanes 520 to prevent rotation of the lead screw 514, as best shown in FIGS. 83 and 86.

[0090] According to one embodiment, as shown in Figs. 84-86, the threaded portion 522 of the lead screw 514 engages with the internal threads of a nut 524 connected to the plunger 516. According to another embodiment, the nut and its internal threads are integrally formed with the plunger as a unitary structure. Additionally, a constant force spring 526 is received within the drum portion 518 and biases the lead screw 514 in a rotational direction. According to one embodiment, the spring 526 is secured to the base cover 504. According to another embodiment, as shown in Figs. 84-86, a drive assembly housing 528 is disposed within the system and the spring 526 is secured to the power pack capacity housing 528.

[0091] Unlike helical springs, such as compression springs, which have a force profile proportional to displacement, constant force springs such as 526 maintain a relatively flat or uniform force profile over long actuation lengths. A uniform force profile advantageously provides an injection force proportional to the spring force. This provides a flat or uniform injection force and therefore a substantially constant injection rate of the medicament. Although spring 526 is shown in FIG. 86 as having only two turns of material, one skilled in the art will appreciate that fewer or more turns can be used. Preferably, an assembler winds spring 526 when drive assembly 500 is assembled, and spring 526 is stored in the wound position until actuation.

[0092] Upon actuation of the system, the needle actuator assembly 510 is released to displace axially (to the right in FIGS. 82-85) under the influence of the biasing member 530 (best shown in FIG. 83) from a pre-use position to a post-use position. During this displacement, the needle actuator assembly 510 abuts the second end 532 of the deactivating body 512, causing the deactivating body 512 to rotate counterclockwise, as shown in FIG. 87. This counterclockwise rotation of the deactivating body 512 releases its first end 513 from engagement with the vane 520. Following disengagement of the first end 513 from the vane 520, the spring 526 unwinds and drives rotation of the lead screw 514 which, in combination with the nut 524, advances the plunger 514 to dispense the medication.

[0093] As the lead screw 514 rotates, the rotation of the drum portion 518 and vanes 520 is visible through a window 534 in the housing. This window 534 shows the progress of the screw in a much more obvious manner than seeing the linear movement of the stopper 536 in the vessel 508. In fact, this rotational movement is many times more sensitive than linear movement. Those skilled in the art will appreciate that the exact amount of advantage or increase will depend on the pitch of the threaded portion 522 of the lead screw 514, the diameter of the drum portion 518, and the number of vanes 520 on the drum portion 518.

[0094] 88-93, a drive assembly 600 for a drug delivery system according to a further embodiment of the present invention is shown. The drive assembly 600 acts to store mechanical energy of a spring and actuate it when triggered. The drive assembly 600 includes a drug barrel 601, a stopper 602 slidably disposed within the barrel 601, a first valve plunger 603, a second valve plunger 604, a first rotating nut 605, and a second rotating nut 606. The drive assembly 600 also includes a rotation indicator 607, a locking element 608, a constant force spring 609 disposed within the rotation indicator 607, and an actuation release or flipper 610. The drive assembly 600 is at least partially disposed within a housing 611 that can be assembled into the drug delivery system.

[0095] A constant force spring 609 is housed within a drum portion 616 of the rotation indicator 607 between the housing 611 and the rotation indicator 607. The de-actuated state of the drive assembly is such that energy is applied by unwinding the spring 609 and this energy is geometrically utilized by the housing 611, the rotation indicator 607, and the deactivation body 610. When the drive assembly 600 is de-actuated, the spring recoils, converting mechanical energy into rotational motion of the rotation indicator.

[0096] The telescoping multi-part plunger is oriented along the axis of force between the drug barrel 601 and the rotation indicator 607. The rotation indicator 607 features a threaded shaft 618. According to one embodiment, the threads are double start and either square or rectangular in nature. The multi-part telescoping plunger includes a two-part threaded nut (first rotating nut 605 and second rotating nut 606) and a two-part plunger (first valve plunger 603 and second valve plunger 604). The second rotating nut 606 is a threaded shaft that mates with the rotation indicator 607 and the first rotating nut 605 and features corresponding threads on its inner and outer surfaces (internal and external threads, respectively). The second rotating nut 606 also has a circular collar 620 (best seen in FIG. 92) at its proximal end that bottoms out against the underside of the second valve plunger 604. The second rotating nut 606 is free to rotate along the force axis. The first rotating nut 605 is also a threaded shaft featuring internal threads that correspond to the external threads of the second rotating nut 606 for coupling thereto.

[0097] According to one embodiment, at one end, the first rotating nut 605 has a hexagonal collar that presses onto the first valve plunger 603 to fixedly connect the first rotating nut 605 to the first valve plunger 603. In the drive assembly 600, the first rotating nut is not free to rotate, but only moves when the power module subassembly is actuated.

[0098] The second valve plunger 604 is a hollow cylindrical component having a small collar 622 at its distal end, a large collar 624 at its proximal end, and an extended L-shaped arm 626 (best seen in FIG. 93) protruding from the large proximal collar 624. According to one embodiment, the small collar 622 is discontinuous and features a four leaf cantilever arm or leaf spring 623 that allows the collar to flex and mate with the first valve plunger 603. The inner surface of the second valve plunger 604 has an undercut down the length that terminates at its proximal end and has a ledge 628 that protrudes radially inward of the large collar 624. The ledge 628 engages the second rotating nut 606 in a telescoping assembly.

[0099] The first valve plunger 603 is also a hollow cylindrical component that attaches to the stopper 602 and mates with the second valve plunger 604. More specifically, the first valve plunger 603 features a cylindrical protrusion 630 on its distal end to mate with the stopper 602. According to one embodiment, as best shown in FIG. 89, four through slots 632 are located in quadrants of the proximal end of the first valve plunger 603 to mate with the leaf spring or arm 623 and small collar portion 622 of the second valve plunger 604. The first and second valve plungers 603 and 604 are slidable together.

[0100] The nesting action is achieved when the constant force spring 609 recoils and the rotation indicator 607 begins to rotate. The threaded attachment between the rotation indicator 607 and the second rotating nut 606 causes the second rotating nut 606 to rotate. However, the second rotating nut 606 cannot rotate because it is threaded onto the first rotating nut 605, and because of the pressure caused by the drug in the barrel 601, it experiences resistance to distal movement and displaces proximally, bottoming out on the radially inwardly projecting ledge 628 of the second valve plunger. The second valve plunger 604 is prevented from moving proximally by the housing 611. As the rotation indicator 607 continues to rotate, the second rotating nut 606 is threadedly engaged with the first rotating nut 605 (which cannot rotate), causing the first rotating nut 605 to move distally and press against the first valve plunger 603 (and stopper 602) to dispense the drug from the barrel 601.

[0101] The first valve plunger 603 is displaced distally relative to the second valve plunger 604 until a small collar 622 (a leaf spring or arm 623 located at the distal end of the second valve plunger 604) engages a corresponding proximal end of a slot 632 in the first valve plunger 603. This locks the relative positions of the first and second valve plungers 603 and 604, and continued rotation of the rotation indicator 607 causes both valve plungers to translate distally (due to their proximal engagement with the ledge 624) also pushing against the second rotating nut.

[0102] The initial and final positions of the telescoping plunger, and therefore the drug dose, are controlled by the rectangular thread profile of the threaded shaft 618 of the rotation indicator 607, the threaded shaft of the drum portion 616 of the rotation indicator 607, and a stepped pin that functions as a locking element 608. According to one embodiment, the threaded shaft of the drum portion 616 of the rotation indicator 607 is single lead and the remainder of the components in the telescoping chain have double lead threads, so that the axial travel distance of the other threaded components is twice the axial travel distance of the lock 608 relative to the rotation indicator.

[0103] According to one embodiment, the lock 608 is cylindrical and features a domed tip on one end and a cylindrical collar on the other end. The external threads of the rotation indicator drum portion 616 together with the slots and undercuts 636 on the bottom of the housing 611 trap the lock 608 in place and allow it to slide parallel to the axis of force. Thus, when the spring 609 is released and the rotation indicator 607 turns, the lock 608 also translates and creates a positive stop when the distal end of the external threads of the rotation indicator drum portion 616 is reached.

[0104] One advantage of embodiments of the drive assembly 600 includes the use of a constant force spring 609, whose mechanical energy is converted into a substantially constant linear force on the drug within the barrel 601. This in turn results in a uniform drug release rate. Another advantage is that by using a screw-type driven telescoping plunger, the drive assembly can provide up to 0.75 inches (19.05 mm) of in-line space savings compared to other plunger designs. Additionally, the drive assembly provides controlled drug dosage with initial and final mechanical constraints within the same component.

[0105] As mentioned above, other drug delivery systems utilize a compression coil spring that exerts a maximum force upon actuation and eventually decreases as the spring unfolds. The decreasing force on the plunger translates to a variable drug delivery time and drug exit pressure. By using a constant force spring, the force acting on the plunger is constant from the beginning to the end of the dose. Furthermore, the distance the coil spring must travel in addition to the static plunger length that must travel inside the drug container creates a long assembly. In contrast, in embodiments of the present invention, the constant force spring is radially contained and does not require additional space before or after actuation. Furthermore, the nested plunger aspect allows the plunger length of the plunger to be significantly reduced compared to the length of a static plunger.

[0106] Conventional drug delivery systems have variable dose accuracy performance because the mechanical components that enable drug delivery create geometric dependencies due to bottoming out into containers that cannot be manufactured to close tolerances. Some embodiments of the present invention create control over the start and end times of the translational plunger through the use of thread forms and constant force springs in the rotation indicator.

[0107] The drive assembly creates a space saving configuration along with well controlled time, volume and pressure for the drug delivery device, resulting in a more attractive, compact and precise drug delivery device.

[0108] Some embodiments of the drive assembly implement three rotating threaded shafts to save approximately 0.75 inches of linear space. In other embodiments, the same concept can be employed using two rotating threaded shafts, resulting in a space savings of approximately 0.5 inches (12.7 mm). Some embodiments of the present invention convert the rotational energy of a constant force spring into the translational force motion of a plunger.

[0109] 94-100, a spacer assembly 660 according to a further embodiment of the present invention is shown. The spacer assembly 660 is similar to the spacer assembly 460 discussed above and shown in FIGS. 76-78 and operates in a similar manner to achieve similar advantages. The spacer assembly 660 includes a fixed spacer 666 and an adjustable spacer 668. The fixed spacer 666 is configured to be received by the stopper 462 with a protrusion 670 engaging the stopper 462 to secure the fixed spacer 666 within the stopper 462, although other suitable fastening arrangements such as threads may be utilized. The fixed spacer 666 includes an internal thread 672 that receives an external thread 678 of the adjustable spacer 668. The fixed spacer 666 includes a plurality of detents 674 disposed on a helical portion of the fixed spacer 666. The adjustable spacer 668 includes a spring detent arm 676 that engages one of the detents 674 to prevent rotation and axial displacement of the adjustable spacer 668 relative to the fixed spacer 666. The spring detent arm 676 is shaped and configured to pass in one direction over the detents 674 to allow rotation and axial displacement of the adjustable spacer 668 away from the fixed spacer 666. The adjustable spacer 668 may be initially secured to the fixed spacer 666 via the threads 672, 678 by applying a force to the top of the spring detent arm 676 biasing the spring detent arm 676 away from the detents 674 to allow the spacers 666, 668 to be secured together. Thus, in the same manner as described above with respect to the spacer assembly 460, the adjustable spacer is free to rotate in one axial direction to adjust the length of the spacer assembly 660.

[0110] 94-100, the spacer assembly 660 further includes a shim 680 configured to be received and secured to the adjustable spacer 668. Rather than providing multiple sizes of adjustable spacers 468, 668, multiple sizes of shims 680 may be provided to accommodate multiple different fill volumes within the container 14. The shim 680 may be secured to the adjustable spacer 668 via a connector 682 extending from the shim 680 that is received by the adjustable spacer 668 using a snap fit, although other suitable securing configurations may be utilized. A central portion 684 of the fixed spacer 666 is configured to be engaged while the adjustable spacer 668 is rotating relative to the fixed spacer 666 to prevent rotation of the fixed spacer 666 with the adjustable spacer 268. The central portion 684 of the fixed spacer 666 is accessible through an opening in the shim 680.

[0111] Elements of one disclosed embodiment may be combined with elements of one or more other disclosed embodiments to form different combinations, all of which are contemplated as falling within the scope of the present invention.

[0112] While this disclosure has been described as having an exemplary design, the disclosure can be further modified within the spirit and scope of the disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the disclosure using its general principles. Further, this application is intended to cover such departures from the disclosure as come within known or customary practice in the art to which this disclosure pertains and which fall within the scope of the appended claims.

Claims

1. 1. A drug delivery system comprising: Housing and A drive assembly; a needle having a retracted position and an extended position; 1. A needle actuator assembly, comprising: a needle actuator body received within the housing and configured to move from a pre-use position in which the needle is in a retracted position to a use position in which the needle is in an extended position, and to a post-use position in which the needle is in the retracted position, the needle actuator body having a button contact surface; an actuator button received within the housing, the actuator button being movable between a first position and a second position relative to the housing, the actuator button including a lockout arm; movement of the actuator button from the first position to the second position causes the needle actuator body to move from a pre-use position to a use position; a lockout arm of the actuator button disposed in engagement with a button contact surface of the needle actuator body when the needle actuator body is in a use position to limit movement of the actuator button from the second position to the first position; 11. A drug delivery system comprising: a needle actuator body having a lockout arm disposed above a button contact surface of the needle actuator body to prevent the needle actuator body from moving upward when the needle actuator body is in a pre-use position.

2. 2. The drug delivery system of claim 1, wherein the lockout arm of the actuator button disengages from the button contact surface of the needle actuator body when the needle actuator body is in the post-use position to allow movement of the actuator button from the second position to the first position.

3. 3. The drug delivery system of claim 2, wherein a portion of the needle actuator body engages the actuator button to limit movement of the actuator button from the first position to the second position when the needle actuator body is in a post-use position.

4. 2. The drug delivery system of claim 1, further comprising a button spring including a first bearing surface, a second bearing surface disposed opposite the first bearing surface, and a spring arm, the spring arm of the button spring configured to bias the actuator button to the first position.

5. 5. The drug delivery system of claim 4, wherein the actuator button is movable from a first axial position to a second axial position spaced from the first axial position, and the actuator button is restricted from moving from the first position to the second position when the actuator button is in the first axial position.

6. 6. The drug delivery system of claim 5, wherein the housing includes a first bearing flank and a second bearing flank spaced apart from the first bearing flank, the first bearing surface of the button spring engaging the first bearing flank of the housing and the second bearing surface of the button spring engaging the second bearing flank of the housing.

7. 7. The drug delivery system of claim 6, wherein one of the first and second bearing ramps includes a stopper configured to prevent the actuator button from moving from the second axial position to the first axial position.

8. 7. The drug delivery system of claim 6, wherein the housing includes a spring arm bearing surface configured to engage the spring arm of the button spring.

9. 9. The drug delivery system of claim 8, wherein the spring arm bearing surface includes a stop configured to prevent movement of the actuator button from the second axial position to the first axial position.

10. The drive assembly includes: A drug barrel; a stopper slidably disposed within the medicine barrel; A first valve plunger; A second valve plunger; A first rotating nut; A second rotating nut; The drug delivery system of claim 1 .

11. The drive assembly further comprises: A rotation indicator; A locking element; a constant force spring disposed within the rotation indicator; A deactivating body and 11. The drug delivery system of claim 10, wherein the constant force spring imparts a substantially constant linear force to the drug barrel.

12. 1. A drug delivery system comprising: Housing and A drive assembly; a needle having a retracted position and an extended position; 1. A needle actuator assembly, comprising: a needle actuator body received within the housing and configured to move from a pre-use position in which the needle is in a retracted position to a use position in which the needle is in an extended position, and to a post-use position in which the needle is in the retracted position, the needle actuator body having a button contact surface; an actuator button received within the housing, the actuator button being movable relative to the housing between a first position and a second position, the actuator button being movable relative to the housing from a first axial position to a second axial position spaced from the first axial position, the actuator button being restricted from moving from the first position to the second position when the actuator button is in the first axial position, the actuator button including a lockout arm; movement of the actuator button from the first position to the second position causes the needle actuator body to move from a pre-use position to a use position; 11. A drug delivery system comprising: a needle actuator body having a lockout arm disposed over the button contact surface of the needle actuator body to prevent the needle actuator body from moving upward when the needle actuator body is in the pre-use position.

13. 13. The drug delivery system of claim 12, further comprising a button spring including a first bearing surface, a second bearing surface disposed opposite the first bearing surface, and a spring arm, the spring arm of the button spring configured to bias the actuator button to the first position.

14. 14. The drug delivery system of claim 13, wherein the housing includes a first bearing flank and a second bearing flank spaced apart from the first bearing flank, the first bearing surface of the button spring engaging the first bearing flank of the housing and the second bearing surface of the button spring engaging the second bearing flank of the housing.

15. 15. The drug delivery system of claim 14, wherein one of the first and second bearing ramps includes a stop configured to prevent the actuator button from moving from the second axial position to the first axial position.

16. 15. The drug delivery system of claim 14, wherein the housing includes a spring arm bearing surface configured to engage the spring arm of the button spring.

17. 17. The drug delivery system of claim 16, wherein the spring arm bearing surface includes a stop configured to prevent movement of the actuator button from the second axial position to the first axial position.

18. 13. The drug delivery system of claim 12, wherein the lockout arm of the actuator button engages the button contact surface of the needle actuator body to limit movement of the actuator button from the second position to the first position when the needle actuator body is in the use position.

19. 20. The drug delivery system of claim 18, wherein the lockout arm of the actuator button is disengaged from the button contact surface of the needle actuator body when the needle actuator body is in the post-use position to allow movement of the actuator button from the second position to the first position.

20. 20. The drug delivery system of claim 18, wherein a portion of the needle actuator body engages the actuator button to limit movement of the actuator button from the first position to the second position when the needle actuator body is in the post-use position.

21. 14. The drug delivery system of claim 13, wherein the button spring is integrally formed with the actuator button.

22. The drive assembly includes: A drug barrel; a stopper slidably disposed within the medication barrel; A first valve plunger; A second valve plunger; A first rotating nut; A second rotating nut; The drug delivery system of claim 12, comprising:

23. The drive assembly further comprises: A rotation indicator; A locking element; a constant force spring disposed within the rotation indicator; A deactivating body and 23. The drug delivery system of claim 22, wherein the constant force spring imparts a substantially constant linear force to the drug barrel.

Citation Information

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