Injection device

[0001] The invention relates to an injection device of the type that it includes a syringe, moves it, releases its contents, and then withdraws it automatically.

BACKGROUND OF THE INVENTION [0002] The previously known injection devices shown in WO95 / 35126 and EP-A-0516473 typically use a drive spring and trigger, which when released causes the drive spring to act on the syringe when the locking mechanism is also meshed. WO 2005/115510 also discloses an injection device of this kind.

[0003] In general, the trigger can rotate around an axis of rotation, which means that when it is lowered at the first end, the second end (which usually meshes with the drive spring) is also inverted, thereby releasing the drive spring, resulting in the syringe extends and its contents are released. The trigger includes a protrusion that can engage with a notch on the releasable locking mechanism when the releasable locking mechanism is engaged, enabling the trigger to be activated. When the releasable locking mechanism is not interlocked, the projection rests on a portion of the releasable locking mechanism preventing the trigger from rotating and the drive spring releasing. Thanks to this, you can avoid accidental triggering.

[0004] A problem with this type of injection device is that the projection on the trigger bends when force is applied to the trigger and the releasable locking mechanism is not meshed. A significant force acting on the trigger may cause sufficient protrusion of the protrusion so that the end of the protrusion can engage with the notch in the releasable locking mechanism, in effect enabling the trigger to be actuated even when the releasable locking mechanism was not meshed. Another pending patent application, published under GB 2424835, addresses this problem by providing a projection on a releasable locking mechanism and a notch on the trigger. Thanks to this, when the trigger is applied by force, when the releasing locking mechanism is not meshed, the trigger and protrusion bend so that the protrusion is repelled from the notch, which limits the risk of accidental activation of the trigger.

[0005] US 6575939 B describes an injection device having a locking mechanism that prevents trigger actuation until the locking mechanism is engaged. The trigger includes a lateral projection which must engage with the corresponding holes in the locking mechanism before it engages.

[0006] WO 03/047663 A2 discloses an automatic injection device comprising a needle that is automatically inserted at the injection site upon actuation of the injection device. The device may include a needle locking device including a clamp that ensures that the needle assembly is in a locked position before and after use.

[0007] US4194505 discloses a subcutaneous module having a trigger comprising a trigger element that prevents the piston from being released before the trigger is pressed. The trigger also includes a pin that must be inserted into the hole before the trigger can be pressed.

SUMMARY OF THE INVENTION [0008] The injection device according to the invention is designed to solve this and other problems.

[0009] Accordingly and in accordance with the first aspect of this invention, an injection device is provided that includes:

a housing defining a first axis and adapted to receive a syringe having an outlet nozzle, which means that the syringe can move between a retracted position in which the outlet nozzle is contained within the housing and an extended position in which the outlet nozzle exits the housing through the outlet opening;

a drive which is affected and which in turn acts on the syringe;

a trigger that can move from a rest position in which it causes the drive to be stopped to an active position in which it no longer causes the drive to be stopped allowing the contents of the syringe to be released through the outlet nozzle;

a releasable locking mechanism that is movable from a first position in which the trigger is secured against movement to its active position, to a second position in which the trigger can be moved to its active position, characterized in that the trigger includes a first recess portion wherein the first portion is located from the first trigger end in a direction substantially parallel to the first axis; and the releasable locking mechanism includes a projection along a second axis for connecting to the first trigger portion when the releasing locking mechanism is in the first position, and for engaging with a recess when the releasing locking mechanism is in the second position; and the projection includes a first elongated projection to engage with the recess edge when the releasable locking mechanism is in the second position and the trigger is in the active position, preventing movement of the trigger from the active position to the rest position.

[0010] Thus, when force is applied to the trigger when the locking mechanism is in the first position (i.e., the active position), the first trigger part and the protrusion deform so that the protrusion is withdrawn from the recess, thereby reducing the risk of accidental activation of the trigger . [0011] In addition, the trigger may further include a second portion that is positioned in a recess at the first trigger portion and which engages with the elongated projection when the releasable locking mechanism is in the second position and the trigger is in the active position.

[0012] Accordingly, the trigger can be maintained in the rotational position following activation, thereby indicating that the injection device has been used.

[0013] Preferably, the releasable locking mechanism comprises biasing means for biasing the protrusions relative to the second part.

[0014] Preferably, the first trigger portion includes a second longitudinal projection arranged on the first portion such that the projection is positioned between the recess and the second longitudinal projection when the trigger is in a position such that the second longitudinal projection is in contact with the projection when attempting to move drain from rest position.

[0015] The second longitudinal projection prevents the first trigger portion and the projection from bending so that the end of the projection would extend beyond the end of the first portion, which would cause the trigger to rotate.

[0016] The protrusion may include an inclined surface that is at an angle to the second axis, thereby ensuring that the protrusion enters the recess smoothly when the locking mechanism disengages.

[0017] Preferably, the first axis and the second axis are perpendicular to each other, ensuring that the projection and the first part are optimally arranged so that the projection enters the recess when the locking mechanism disengages, but also that the projection and the first part bend so that avoid accidental triggering of the trigger when the release mechanism is activated.

BRIEF DESCRIPTION OF THE DRAWINGS [0018] Below, by way of example, the invention will be described based on the attached drawings, in which:

Figure 1 is a perspective view of an injection device according to the invention;

Figure 2 is a side view of the injection device of Figure 1, with the top of the housing not shown;

figure 3 is a side view of the injection device shown in figure 2, no further elements being shown;

Figure 4 is a top view of the injection device shown in Figure 2;

Figure 5 is a perspective view of the trigger and releasable locking mechanism in accordance with one embodiment of the invention;

Figure 6 is an alternative perspective view of the trigger and releasable locking device shown in Figure 5.

DETAILED DESCRIPTION OF THE DRAWINGS [0019] Figs. 1 to 4 show an injection device 110 according to a first embodiment of the invention. The injection device 110 has an injection device housing 112 and a longitudinal axis 101.

[0020] In the housing 112 there is a syringe 122. The injection device 110 has a trigger 114 and a releasable locking mechanism 116. The trigger 114 has a first end 114a and a second end 114b. The trigger 114 can rotate about a rotation axis 115 from a rest position (as shown in Figure 2) to an active position. The second end 114b of the trigger 114 connects to the drive clutch 121 which is affected by the drive spring 120. The drive clutch 121 is connected to the syringe 122.

[0021] The rotary movement of the trigger 114 about the rotation axis 115 in the R direction (i.e. down into the housing 112 at the first end 114a) causes the second end 114b of the trigger 114 to disengage from the drive clutch 121, thereby enabling the drive spring 120 to drive syringes 122 (via drive clutch 121) along the longitudinal axis 101 outside the opening 118 in the housing 112.

[0022] The releasable locking mechanism 116 engages with the slide sleeve 126, which protrudes in a first position from the opening 118 in the housing 112. The releasable locking mechanism 116 is activated by the movement of the slide sleeve 126 along the longitudinal axis 101 into the housing 112 to the second position. [0023] The first end 126a of the sliding sleeve 126 may be positioned against the body of the person being administered the drug, thereby deactivating the releasable locking mechanism 116 and allowing the trigger 114 to rotate in the R direction from the rest position to the active position. [0024] As can be seen in Figs. 5 and 6, trigger 114 is provided at the first end 114a with a first locking portion 150 having a notch 152. The first locking portion 150 extends from the first trigger end 114a of the trigger 114 in a direction substantially parallel to the longitudinal axis 101.

[0025] The releasable locking mechanism 116 includes a projection 154 that projects in a direction along the transverse axis 181 that is perpendicular to the longitudinal axis 101. The notch size 152 corresponds to the projection 154.

[0026] When the releasable locking mechanism 116 is in the first position, the end 154a of the projection 154 abuts the lower surface 156 of the locking portion 150, thereby preventing the rotational movement of the trigger 114.

[0027] When the releasable locking mechanism 116 is in a second position (not shown) after the sliding sleeve 126 has moved into the housing 112, the notch 152 is above the projection 154, allowing it to pass over the projection 154, while the trigger 114 is subjected to force facing down. As a result, the trigger 112 is no longer secured against rotation and detaches from the drive clutch 121, thereby extending the syringe 122. [0028] The projection 154 includes a first elongated projection 160. The trigger 114 includes a second portion 162 that extends into the recess 152 from the first trigger portion 150 that is arranged to engage the second portion 162 after the rotational movement of the trigger 114 such that the first elongated projection 160 is locked over the second portion 162, thereby counteracting the movement of the trigger 114 from the active position to the rest position.

[0029] The releasable locking mechanism 116 includes pre-tensioning elements in the form of resilient arms 171 which act on the inner surface of the housing 112 for pivoting the releasable locking mechanism 116 and the sliding sleeve 126 towards the outside of the opening 118. Thus, when the trigger 112 is actuated, the first longitudinal projection 160 is locked over the second trigger portion 162 of the trigger 112, keeping trigger 112 in the active position.

[0030] The first portion 150 of the trigger 114 includes a second elongated projection 164 on the lower surface 156 of the first portion 150 which is between the notch 152 and the end of the first portion 150. The second elongated projection 164 rests on the projection 154 when the force exerts the trigger 114 towards R and the releasable locking mechanism is in the first position. This prevents projection 154 from moving to a position where its end 154a moves over the end of the first portion 150, which will allow the trigger 114 to rotate while the releasable locking mechanism 116 is still locked, preventing accidental actuation of the injection device 110.

[0031] The projection 154 has an inclined surface 166 that is angled with respect to the second axis 181, which allows the second portion 162 of the trigger 114 to move over the projection

154 more effectively when the trigger 114 is rotated, and when the releasing locking mechanism 116 is disengaged.

[0032] It should of course be understood that the present invention has been described above by way of example only, and it is possible to introduce detailed modifications without departing from the scope of the invention.

22901 / EP / 13

EP 2 366 415 B1