Safety injection device

Abstract

An injection device for injecting a substance into a body, the injection device comprising: a barrel (100) having the substance, a stopper (103) and an injection needle (101) slidably engaged inside the barrel (100); a plunger rod (110) coupled to the stopper (103) and movable to inject the substance, a locking clip (150) fixed relative to the barrel (100) and having at least two clamps (151), the locking clip The clamp is engaged with the plunger rod (110) so as to prevent injection movement of the plunger rod (110) relative to the barrel (100), and a needle shield (130), the needle shield including a trigger portion (134), the needle shield (130) being configured to be slidably engaged relative to the injection needle (101), wherein the trigger portion (134) is configured to open the locking clamp (150) when the needle shield (130) moves from an initial position to a retracted position.

Description

Technical Field

[0001] The present invention relates to a medical injection system for self-administration of a substance or a pharmaceutical composition. Background Art

[0002] Medical injection systems that allow self-administration of pharmaceutical compositions have been developed so that patients with incurable or long-term diseases can administer their own pharmaceutical compositions without the need for any medical personnel. Therefore, these medical injection systems generally provide simplified operation, for example, by combining several steps into a single distal movement.

[0003] This medical injection system is usually arranged in a position where the injection needle intended to deliver the pharmaceutical composition is hidden or covered by the medical injection system and at least the following steps can be performed:

[0004] The first step of acupuncture is to insert the injection needle into the patient's body.

[0005] The second step of injection is to inject or deliver the pharmaceutical composition into the patient's body through an injection needle.

[0006] However, the following problem may occur: the injection step is triggered before the needle sticking step is completed, so that the injection needle may not be inserted into the patient's body or may be inserted at an inappropriate depth of the patient's skin. Such failed administration usually results in a waste of precious pharmaceutical composition and inconvenience to the patient.

[0007] The object of the present invention is to solve the above problems, so as to provide a medical injection system which is low in cost, simple in operation and capable of minimizing the number of failed drug administrations. Summary of the invention

[0008] To this end, a first aspect of the present invention is an injection device for injecting a substance into a body, the injection device comprising:

[0009] (a) a barrel adapted to receive a substance and having a stopper and an injection needle slidably engaged inside the barrel;

[0010] (b) a plunger rod configured to push the stopper and movable to inject a substance when a pushing force is applied to the plunger rod,

[0011] (c) a locking clip fixed relative to the barrel and having at least two jaws adapted to engage the plunger rod in a primary position of the plunger rod so as to prevent injection movement of the plunger rod relative to the barrel, and

[0012] (d) a needle shield including a trigger portion, the needle shield being configured to be slidably engaged relative to the injection needle so as to define an initial position in which the needle shield covers the injection needle and a retracted position in which the needle shield does not cover at least a portion of the injection needle;

[0013] The trigger portion is configured to open the locking clip when the needle shield moves from the initial position to the retracted position so as to disengage the locking clip from the plunger rod and allow the injection movement of the plunger rod.

[0014] Due to the engagement of the locking clip with the plunger rod, at least the ejection movement and preferably any movement of the plunger rod is prevented as long as the needle shield is not in the retracted position and the injection needle is not inserted into the body at a predetermined depth. The direct engagement of the needle shield with the locking clip preferably occurs at the end portion of the movement of the needle shield, for example 80%, 85% or 90% of the movement of the needle shield towards the retracted position. For example, the two clamps can be rotated or deflected away from the longitudinal axis of the injection device or the longitudinal axis of the plunger rod. More than two clamps, for example three or four clamps, can be provided.

[0015] Advantageously, the plunger rod comprises an intermediate stop and the two jaws of the locking clip are arranged to engage the intermediate stop in the primary position of the plunger rod. The intermediate stop may comprise one or several abutment surfaces, grooves or protrusions extending from the axial shaft of the plunger rod. The jaws may have a thick edge to increase resistance to distal forces when the locking clip is not opened.

[0016] Advantageously, the needle shield is further movable to a safe position in which the needle shield permanently covers the injection needle, and

[0017] The injection device further comprises:

[0018] (e) an operating stop configured to prevent the needle shield from moving to a safety position,

[0019] (f) a flexible support supporting the operating stop and fixed with respect to the cylinder,

[0020] (g) a deflection member configured to contact the operating stopper and / or the flexible support and receive a thrust force from the plunger rod when moving the plunger rod to a threshold position;

[0021] Wherein the deflection member is further configured to move under the thrust so as to deflect the flexible support and release the operating stop.

[0022] This safety position of the needle shield may be located distally of the initial position of the needle shield. Thus, it allows preventing or limiting accidental needle sticks and allows safe disposal after use of the injection device. In addition, since the safety position of the needle shield is adopted only after the threshold position of the plunger rod has been met, the user can change the injection site, i.e. the location where the substance is injected into the body, at any time before this threshold position of the plunger rod. The threshold position may be located at 70% to 95%, preferably 80% to 90%, of the injection movement of the plunger rod.

[0023] Advantageously, the deflection member comprises:

[0024] an abutment surface configured to receive a thrust force of the plunger rod when the plunger rod is in a threshold position, and

[0025] An inclined portion is configured to slide on the flexible support and / or the deflection member to deflect the flexible support when the deflection member moves under the thrust of the plunger rod.

[0026] This deflection component is easy to produce and assemble. It also allows reliable operation.

[0027] Advantageously, the plunger rod comprises a push surface adapted to transmit a thrust to an abutment surface of the deflection member. The plunger rod is preferably adapted to be pushed by a user, for example by means of a thumb surface. Such a plunger rod is easy and reliable to operate and simple to produce.

[0028] Advantageously, the injection device further comprises a housing housing the locking clip, the barrel, the needle shield and the deflection member, and the operating stop and the flexible support are fixed to the housing or are part of the housing. Preferably, the barrel is held and fixed inside the housing, for example by a rigid clip clamping a flange or another part of the barrel.

[0029] Advantageously, the housing comprises a distal unit housing the needle shield and the barrel and a proximal unit housing the locking clip and the deflection member.This two-part housing is easy to manufacture and assemble.

[0030] Advantageously, the distal unit of the housing comprises a longitudinal window providing visual access to the barrel.Since the deflection member and the locking clip are housed in the proximal portion of the housing, direct observation can be obtained to inspect the substance prior to injection and to follow the stopper movement during injection.

[0031] Advantageously, the resilient members are arranged to push-engage with the needle shield so as to move the needle shield from the retracted position to the initial position and / or the safety position. Preferably, the resilient members are housed in the proximal unit of the housing, which allows the view through the window to be unobstructed. These resilient members may be cylindrical springs arranged around the deflection means and the locking clip, which allow construction of a simple and thin injection device that can be easily transported and stored.

[0032] Advantageously, the deflection member comprises a longitudinal tab or another form of tab adapted to be ejected from the housing when the deflection member moves under the thrust of the plunger rod. Thus, this tab acts as an end-of-dose indicator to provide a clear signal to the user that the injection has been completed.

[0033] Advantageously, the injection device comprises a safety locking member adapted to lock the needle shield to the housing when the needle shield is in the safety position. For example, the safety locking member comprises: at least one peg provided on one of the housing and the needle shield; and at least one notch provided on the other of the housing and the needle shield, the notch being adapted to receive and retain the peg in the safety position of the needle shield.

[0034] Advantageously, the needle shield further comprises at least one longitudinal arm extending along the barrel and comprising a distal end having a trigger portion.This needle shield is easy and inexpensive to manufacture and allows a longitudinal window to be provided on the housing. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Other features and advantages of the present invention will appear more clearly from the following detailed description of certain non-limiting examples of the invention illustrated by the accompanying drawings, in which:

[0036] - Figure 1 A perspective view showing an injection device according to an example of the present invention in a ready-to-use state;

[0037] - Figure 2 Represents a proximal unit without a housing Figure 1 A perspective view of an injection device;

[0038] - Figure 3 express Figure 1 A cross-sectional view of an injection device;

[0039] - Figure 4 express Figure 1 A perspective view of a plunger rod of an injection device;

[0040] - Figure 5 express Figure 1 A perspective view of a distal unit of a housing of an injection device;

[0041] - Figure 6 express Figure 1 A perspective view of a needle shield of an injection device.

[0042] - Figures 7A to 7B express Figure 1 Two perspective views of the locking clip of the injection device,

[0043] - Figure 8 express Figure 1 A perspective view of a deflection component of an injection device,

[0044] - Fig. 9 Indicates that there is no cylindrical spring in the main position Figure 2 A partial side view of the injection device,

[0045] - Fig.10 During acupuncture Figure 2 A side view of the injection device,

[0046] - Fig.11 During acupuncture Figure 2 A partial side view of an injection device illustrating the opening of the locking clip,

[0047] - Fig.12 During acupuncture Figure 2 A partial side view of the injection device,

[0048] - Fig.13 Indicates the threshold position of the plunger rod without the locking clip Figure 2 A partial side view of the injection device,

[0049] - Fig.14 Indicates that the needle shield is in the safe position. Figure 2 Side view of the injection device. DETAILED DESCRIPTION

[0050] The injection system of the present invention is intended for administration of substances, such as one or several parenteral pharmaceutical compositions, by a user, such as a healthcare provider, or preferably by a patient, in a simplified operation.

[0051] Thus, in this application, the distal direction has to be understood as the injection direction with reference to a medical injection device, and the proximal direction is the opposite direction, i.e. the direction towards the hand of the user (i.e. the medical attendant or the patient). In addition, pharmaceutical compositions have to be understood as all kinds of injectable pharmaceutical compositions suitable for therapeutic, aesthetic, prophylactic or diagnostic applications.

[0052] refer to Figures 1 to 3 , shows an injection device according to a preferred example of the present invention. The injection device includes a barrel 100 ( Figure 3100), which has an injection needle 101, a distal flange 102 and a stopper 103 that is slidably engaged in the barrel. The injection needle 101 can be glued, stacked or detachably fixed to the barrel 100, but is preferably glued or stacked. The barrel can be hard plastic, metal, but is preferably glass.

[0053] The plunger rod 110 is coupled to the stopper 103, or at least configured to push the stopper 103, and is preferably adapted to be moved manually, for example by a user. As is known, a distal force applied to the plunger rod 110 results in moving the stopper 103 to perform an injection of a substance. The plunger rod 110 is movable in an injection movement from a primary proximal position to a final distal position. Figure 4 , the plunger rod 110 includes: a longitudinal shaft 111 having a cross-shaped cross-section in the example of the figure; a proximal portion 112 ; a distal coupling portion 113 ; and an intermediate stopper 114 .

[0054] The proximal portion 112 comprises at its distal end: a thumb surface 112a adapted to be pushed by a user's thumb; and a push surface 112b. The distal coupling surface 113 is adapted to be coupled to the plug 103, for example by clamping, gluing or screwing. In the example of the figure, the intermediate stop 114 and the push surface 112b are transverse surfaces protruding from the cross-shaped longitudinal shaft 111.

[0055] refer to Figures 1 to 3 as well as Figure 5 The cylinder 100 is received and fixed in the housing 120 by its distal flange 102. The housing comprises a distal unit 121 which surrounds and holds the cylinder 100 due to a rigid clamp 123, and a proximal unit 122 which is located around and proximal to the distal flange 102 of the cylinder 100. Figure 2 and 5 The proximal unit 122 of the housing 120 is omitted. The distal unit 121 includes a central cavity accommodating the cylinder 100, and further includes a distal ring 124 and a side protrusion 125.

[0056] The side protrusions 125 are hollow and each include a through slot. One or several longitudinal windows 128 made of a transparent material may be arranged on the housing to provide visual access to the cylinder 100. The distal unit 121 and the proximal unit 122 of the housing 120 are clamped together, but may also be screwed or glued. The distal unit 121 of the housing 120 further includes a flexible support 126 that protrudes from a proximal end 127 and has a proximal surface or protrusion that acts as an operating stop 126a.

[0057] refer to Figures 1 to 3 as well as Figure 6, the needle shield 130 is provided to be slidably engaged within the housing 120. The needle shield 130 comprises a safety tube 131 from which two rigid arms 132 protrude in the proximal direction. The rigid arms 132 each comprise a tip having a stop portion 133 and a trigger portion 134 in the form of a triangular or inclined portion. In addition, the rigid arms 132 further comprise one, and preferably two, pegs 135 extending transversely from the rigid arms 132.

[0058] about Figure 2 and 3 , the proximal unit 122 of the housing 120 encloses a resilient member in the form of a cylindrical spring 140, which encloses the locking clip 150 and the defective component 160. The cylindrical spring 140 is adapted to push engagement on the proximal side of the stop portion 133 of the needle shield 130 and on the opposing surface of the proximal unit 122 of the housing 120.

[0059] exist Figures 7A to 7B , the locking clip 150 includes two jaws 151 surrounding a central hole 152, the jaws being connected to each other by a flexible intermediate portion 153, and each jaw being further connected to two legs 155 extending distally due to a flexible connecting portion 154. The legs of the locking clip 150 are intended to contact or be fixed to the proximal end 127 of the distal unit 121 of the housing 120. The jaws 151 may have a thick edge 151a surrounding the central hole 152.

[0060] refer to Figure 8 The deflection member 160 includes an abutment surface 161 having a through hole 162 and two side surfaces 163. The side surface 163 further includes an inclined portion 164, wherein the slope or thickness increases from the distal side to the proximal side of the inclined portion, i.e., at Figure 8 The side surfaces 163 each have two through grooves 165 intended to house the legs 155 and the longitudinal tabs 166 of the locking clip 150 .

[0061] about Fig. 9 , showing the proximal region of the injection device with the cylindrical spring 140 and the proximal unit 122 of the housing 120 omitted. The locking clip 150 is visible, with the legs 155 extending distally through the through grooves 165 of the locking clip 150 and contacting or being fixed to the proximal end 127 of the distal unit 121 of the housing 120. The deflection member 160 contacts the flexible support 126 and the operating stop 126a via its inclined portion 164, and its longitudinal tab 166 is received in the through groove of the lateral protrusion 125 of the housing 120. The end of the rigid arm 132 of the needle shield 130 also extends further from the proximal end 127 of the housing distal unit 121, and its stop portion 133 contacts or abuts the operating stop 126a.

[0062] exist Figures 1 to 3 as well as Fig. 9 In the ready-to-use state of the injection device of the present invention, the safety tube 131 of the needle shield 130 covers the injection needle 101, and the distal movement of the needle shield 130 is prevented by the contact between the stopper portion 133 and the operation stopper 126a. However, the proximal movement of the needle shield 130 is allowed. In addition, the plunger rod 110 is inserted through the locking clip 150 and the deflection member 160 due to the central hole 152 and the through hole 162, respectively. The clamp 151 of the locking clip 150 is in contact with the intermediate stopper 114. Therefore, the distal movement of the plunger rod 110 is prevented by the locking clip 150, and the injection cannot be performed in this ready-to-use state.

[0063] Operation of the injection device

[0064] In operation, the injection device, in particular its distal end including the injection needle 101, is pressed against the body and the needle shield 130 moves proximally, thereby allowing the injection needle 101 to penetrate or puncture the body, such as Fig.10 Therefore, the rigid arm 132 is Fig.10 The arrow shown in FIG. 1 moves proximally, and the trigger portion 134 contacts the clamp 151 of the locking clamp 150 (see FIG. 14 ). Fig.11 ).

[0065] Due to the proximal force exerted on and between the jaws 151 by the trigger portion 134 of the needle shield 130 (see Fig.11 The circled area in the figure), the clamp 151 starts to Fig.11 The clamp 151 is rotated by the arrow visible in FIG. 1 . Thus, the clamp 151 is gradually disengaged from the intermediate stop 114 of the plunger rod 110 by the proximal movement of the needle shield 130 caused by puncturing the body. At the end of the needle puncture, i.e., at the end of the proximal movement of the needle shield 130 into the housing 120, the clamp 151 is disengaged from the intermediate stop 114. Thus, the distal force (see FIG. 1 ) exerted on the thumb surface 112a of the plunger rod 110 is Fig.12 ) allows the plunger rod 110 to move distally, thereby performing injection of the substance into the body by moving the stopper 103 into the barrel 100.

[0066] At this point or even during the injection, in particular in the case of pain or for reasons of convenience, the user may still change his mind about the injection site. The injection device can be withdrawn from the body, the needle shield 130 moves back to its initial position covering the injection needle 101, and the needle stick can be repeated on another part of the body.

[0067] exist Fig.13In the embodiment of the present invention, most of the substance has been injected and the plunger rod 110 is in a threshold position, wherein the push surface 112b of the proximal portion 112 of the plunger rod 110 is in contact with the abutment surface 161 of the deflection member 160. The plunger rod 110 is not in its final distal position and can still move distally. In addition, the inclined surface 164 of the deflection member 160 is in contact with the flexible support 126 and / or with the operating stop 126a of the housing 120. Therefore, the continuous force applied by the user on the plunger rod 110 to perform the injection pushes the deflection member 160 distally toward the distal unit 121 of the housing 120 (see Fig.13 ), and the inclined surface 164 deflects the flexible support member 126 inwardly, that is, toward the longitudinal axis 111 of the plunger rod (see Fig.13 ). Note that for clarity, Fig.13 The locking clip 150 is omitted.

[0068] The deflection of the flexible support 126 moves the operation stopper 126a out of its initial position and no longer allows contact with the stopper portion 133 of the needle shield 130. Therefore, at the end of the injection, i.e., when the plunger rod 110 is in its final distal position, the injection device can be withdrawn from the body and the needle shield 130 can be moved distally under the force of the cylindrical spring 140. Since there can no longer be contact between the operation stopper 126a and the stopper portion 133, the needle shield 130 can be moved distally under the force of the cylindrical spring 140 until there is contact between the stopper portion 133 and the proximal end 127 of the distal unit 121. Then, the needle shield 130 is in a safety position, positioned distally from the initial position, and wherein the safety tube 131 covers the injection needle 101, as in Fig.14 Visible in.

[0069] exist Fig.14 In the safety position shown in , the needle shield 130 can be blocked or fixed relative to the housing 120 by engaging the pegs 135 located on the rigid arms 132 of the needle shield 130 with corresponding recesses or abutments located on the inner surface (not shown) of the housing 120, thereby acting as a safety locking member. In addition, due to the distal movement of the deflection member 160 under the force transmitted by the plunger rod 110, the longitudinal tab 166 protrudes in the distal direction beyond the side protrusion 125 of the housing 120, thereby acting as an end-of-dose indicator.

[0070] Of course, it should be appreciated that obvious improvements and / or modifications may be implemented by those skilled in the art while still remaining within the scope of the present invention as defined by the appended claims.

[0071] Even though the illustrated geometries of the different parts of the injection device of the present invention are preferred for efficiency and ease of production, such parts are not limited to these specific designs. In particular, the deflection member can have any specific design, provided that the function of deflecting the flexible support can be performed. The locking clamp can also adopt various designs with one or several clamps.

[0072] Additionally, the elastic member is not limited to one or two cylindrical springs, but may include any form of spring or elastic member.The outer surface of the housing may have an ergonomic relief and may include an overmolded surface in a smooth material.

[0073] It is contemplated that the materials of construction of this injection device are polypropylene, polycarbonate and / or acrylonitrile / butadiene / styrene copolymers. The barrel may comprise glass or plastic. Color may be provided on various parts of the injection device, particularly on the tab that acts as an end-of-dose indicator. The window may have graduations or indicators.

Claims

1. An injection device for injecting a substance into a body, the injection device comprising: a barrel (100) adapted to receive the substance and having a stopper (103) slidably engaged inside the barrel (100) and having an injection needle (101); a plunger rod (110) configured to push the stopper (103) and movable to inject the substance when a pushing force is applied to the plunger rod (110), a locking clamp (150) fixed relative to the barrel (100) and having at least two jaws (151) suitable for engaging the plunger rod (110) in a primary position of the plunger rod (110) so as to prevent an injection movement of the plunger rod (110) relative to the barrel (100), and a needle shield (130), the needle shield comprising a trigger portion (134), the needle shield (130) being configured to be slidably engaged relative to the injection needle (101) so as to define an initial position in which the needle shield (130) covers the injection needle (101) and a retracted position in which the needle shield (130) does not cover at least a portion of the injection needle (101); wherein the trigger portion (134) is configured to engage and open the locking clip (150) when the needle shield (130) moves from the initial position to the retracted position so as to disengage the locking clip (150) from the plunger rod (110) and allow the injection movement of the plunger rod (110); in: The needle shield (130) is further movable to a safety position located distal to the initial position of the needle shield, in which the needle shield (130) permanently covers the injection needle (101), and The injection device further comprises: an operating stopper (126a) configured to prevent the needle shield (130) from moving to the safety position, a flexible support member (126) supporting the operating stopper (126a) and fixed with respect to the cylinder (100), a deflection member (160) configured to contact the operation stopper (126a) and / or the flexible support (126) and receive the thrust from the plunger rod (110) when moving the plunger rod (110) to a threshold position; The deflection member (160) is further configured to move under the thrust so as to deflect the flexible support (126) and release the operating stopper (126a).

2. The injection device according to claim 1, Wherein the plunger rod (110) comprises an intermediate stop (114), and the two jaws (151) of the locking clamp (150) are arranged to engage the intermediate stop (114) in the primary position of the plunger rod (110).

3. The injection device according to claim 1, wherein the deflection member (160) comprises: an abutment surface (161) configured to receive the thrust of the plunger rod (110) when the plunger rod is in the threshold position (110), and An inclined portion (164) is configured to slide on the flexible support (126) and / or the operating stopper (126a) when the deflection member (160) moves under the thrust of the plunger rod (110) so as to deflect the flexible support (126).

4. The injection device according to claim 3, wherein the plunger rod (110) comprises a push surface (112b) adapted to transmit the push force to the abutment surface (161) of the deflection member (160).

5. An injection device according to any one of claims 1 to 4, wherein the injection device further comprises a housing (120) accommodating the locking clip (150), the barrel (100), the needle shield (130) and the deflection member (160), and wherein the operating stop (126a) and the flexible support (126) are fixed to the housing (120) or are part of the housing (120).

6. The injection device according to claim 5, wherein the housing (120) comprises: a distal unit (121) accommodating the needle shield (130) and the barrel (100); and a proximal unit (122) that houses the locking clip (150) and the deflection member (160).

7. The injection device of claim 6, wherein the distal unit (121) of the housing (120) comprises a longitudinal window (128) providing visual access to the barrel (100).

8. The injection device according to any one of claims 1 to 4, wherein the injection device further comprises an elastic member, which is arranged to push and engage with the needle shield (130) so as to move the needle shield (130) from the retracted position to the initial position and / or the safety position.

9. An injection device according to claim 6 or 7, wherein the injection device further comprises an elastic member, which is arranged to be pushed into engagement with the needle shield (130) so as to move the needle shield (130) from the retracted position to the initial position and / or the safety position, wherein the elastic member is accommodated in the proximal unit (122) of the housing (120).

10. The injection device according to claim 5, wherein the deflection member (160) comprises a longitudinal tab (166) adapted to be ejected from the housing (120) when the deflection member (160) moves under the thrust of the plunger rod (110).

11. The injection device according to claim 5, further comprising a safety locking member adapted to lock the needle shield (130) to the housing (120) when the needle shield (130) is in the safety position.

12. The injection device of claim 11, wherein the safety lock member comprises: at least one peg (135), the at least one peg being disposed on one of the housing (120) and the needle shield (130); and at least one notch disposed on the other of the housing (120) and the needle shield (130), the notch being adapted to receive and retain the peg in the safety position of the needle shield (130).

13. The injection device according to any one of claims 1 to 4, wherein the needle shield (130) further comprises at least one longitudinal arm (132) extending along the barrel (100) and comprising a distal end having the trigger portion (134).

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