Medicament delivery device

Abstract

A medicament delivery device (100) for the delivery of medicament from a container (12) through a cannula (16). The device comprises a chassis (300), a carriage (200), and an insertion spring (70) for biasing the carriage (200) for movement in an insertion direction with respect to the chassis (300) from a starting position in which the cannula (16) is shrouded to an insertion position in which the cannula (16) is extended. A drive mechanism (400) is provided for driving the container's stopper (22) to expel medicament. The drive mechanism (400) is carried by the carriage (200) and comprises a movable drive member (404), a drive means (40) for applying a driving force to the drive member (404), and force transmission means (406) for transmitting the driving force to the stopper (22). The drive means (40) is arranged around or alongside at least part of the force transmission means (406).

1 .- 84 . (canceled) 
     
     
         85 . A medicament delivery device for the delivery of medicament from a container through a cannula, the container having a stopper for containing the medicament within the container, the device comprising:
 a chassis;   a carriage for retaining the container and the cannula;   an insertion spring for biasing the carriage for movement in an insertion direction with respect to the chassis from a starting position in which the cannula is shrouded to an insertion position in which the cannula is extended;   a coupling mechanism for releasably coupling the insertion spring to the carriage;   a drive mechanism operable to move the stopper along a container axis to expel the medicament through the cannula; and   a retraction spring for biasing the carriage in a retraction direction, opposite to the insertion direction;   wherein the drive mechanism is arranged to activate the coupling mechanism; and   wherein activation of the coupling mechanism causes decoupling of the insertion spring from the carriage, thereby to allow movement of the carriage in the retraction direction under a bias of the retraction spring after delivery of the medicament.   
     
     
         86 . The medicament delivery device according to  claim 85 , wherein the coupling mechanism comprises a coupling member that is movable with respect to the carriage upon the activation of the coupling mechanism to decouple the insertion spring from the carriage. 
     
     
         87 . The medicament delivery device according to  claim 86 , comprising retaining means for preventing movement of the coupling member with respect to the carriage, wherein a retaining means is arranged to release the coupling member thereby to activate the coupling mechanism. 
     
     
         88 . The medicament delivery device according to  claim 87 , wherein the retaining means comprises a retaining element for engagement with the coupling member, wherein the retaining element is movable with respect to the carriage in response to operation of the drive mechanism to disengage from the coupling member. 
     
     
         89 . The medicament delivery device according to  claim 88 , wherein the retaining element disengages from the coupling member when the drive mechanism has moved the stopper through a pre-defined distance. 
     
     
         90 . The medicament delivery device according to  claim 88 , comprising a wheel driven by the drive mechanism, and wherein the retaining element is in threaded engagement with the wheel such that turning movement of the wheel causes disengagement of the retaining element from the coupling member. 
     
     
         91 . The medicament delivery device according to  claim 90 , wherein the drive mechanism comprises a drive member, drive means for applying a driving force to the drive member along a drive axis, and force transmission means for transmitting the driving force from the drive member to the stopper, and wherein the wheel is driven by the force transmission means. 
     
     
         92 . The medicament delivery device according to  claim 91 , wherein the drive axis is parallel to the container axis and the force transmission means is guided in a U-shape around the wheel. 
     
     
         93 . The medicament delivery device according to  claim 88 , wherein the retaining element disengages from the coupling member upon turning movement of the wheel through a pre-determined angle. 
     
     
         94 . The medicament delivery device according to  claim 86 , further comprising an actuator for driving movement of the coupling member. 
     
     
         95 . The medicament delivery device according to  claim 94 , wherein the coupling member is guided for lateral movement with respect to the insertion direction, and wherein the actuator is arranged to apply a lateral force to the coupling member. 
     
     
         96 . The medicament delivery device according to  claim 94 , further comprising actuator drive means for applying a force to the actuator to drive the movement of the coupling member. 
     
     
         97 . The medicament delivery device according to  claim 96 , wherein the actuator drive means comprises a constant force spring. 
     
     
         98 . The medicament delivery device according to  claim 95 , wherein the actuator comprises a crank having a crank lever for driving the movement of the coupling member. 
     
     
         99 . The medicament delivery device according to  claim 98 , wherein the carriage comprises a hub for the crank. 
     
     
         100 . The medicament delivery device according to  claim 86 , comprising a link member connected to the insertion spring, wherein the link member is releasably engaged with the coupling member to couple the insertion spring to the carriage, and wherein movement of the coupling member with respect to the carriage causes disengagement of the link member from the coupling member to decouple the insertion spring from the carriage. 
     
     
         101 . The medicament delivery device according to  claim 100 , wherein the link member comprises an engagement formation for engagement with a corresponding engagement formation of the coupling member, and wherein the movement of the coupling member upon the activation of the coupling mechanism causes disengagement of the engagement formations. 
     
     
         102 . The medicament delivery device according to  claim 100 , wherein the carriage comprises guide means for guiding movement of the link member parallel to the insertion direction upon decoupling of the insertion spring from the carriage. 
     
     
         103 . The medicament delivery device according to  claim 102 , wherein the guide means comprises a slot for receiving a clip of the link member. 
     
     
         104 . The medicament delivery device according to  claim 85 , arranged such that the insertion spring is decoupled from the carriage after a delay time has elapsed following the activation of the coupling mechanism. 
     
     
         105 . The medicament delivery device according to  claim 104 ,
 wherein the coupling mechanism comprises a coupling member that is movable with respect to the carriage upon the activation of the coupling mechanism to decouple the insertion spring from the carriage; and   the medicament delivery device further comprising damping means for retarding movement of the coupling member after the activation of the coupling mechanism.   
     
     
         106 . The medicament delivery device according to  claim 105 , wherein the damping means comprises a viscous damper. 
     
     
         107 . The medicament delivery device according to  claim 105 , wherein the damping means comprises a rotary damper. 
     
     
         108 . The medicament delivery device according to  claim 107 ,
 wherein the carriage comprises a hub for a crank having a crank lever for driving the movement of the coupling member;   wherein the hub comprises a chamber of the rotary damper; and   wherein the crank comprises a vane of the rotary damper.   
     
     
         109 . The medicament delivery device according to  claim 85 , comprising a carriage latch arrangement for holding the carriage in the starting position and for allowing the movement of the carriage in the insertion direction under the bias of the insertion spring upon release of the carriage latch arrangement. 
     
     
         110 . The medicament delivery device according to  claim 109 , comprising a trigger component operable to release the carriage latch arrangement. 
     
     
         111 . The medicament delivery device according to  claim 110 , comprising an interlock member that is movable with respect to the chassis to switch the device from a neutral state in which release of the carriage latch arrangement is not possible to a ready state in which the trigger component is operable to release the carriage latch arrangement. 
     
     
         112 . The medicament delivery device according to  claim 111 , wherein the interlock member comprises a housing body for retaining the trigger component. 
     
     
         113 . The medicament delivery device according to  claim 85 , wherein the insertion spring is coupled to the chassis. 
     
     
         114 . The medicament delivery device according to  claim 85 , wherein the insertion spring comprises a tension spring. 
     
     
         115 . The medicament delivery device according to  claim 85 , wherein the retraction spring comprises a compression spring. 
     
     
         116 . The medicament delivery device according to  claim 85 , wherein the chassis comprises a carriage stop for stopping the movement of the carriage when the carriage reaches the insertion position. 
     
     
         117 . The medicament delivery device according to  claim 116 , wherein the carriage stop comprises a cushion for damping the movement of the carriage upon impact with the carriage stop. 
     
     
         118 . The medicament delivery device according to  claim 116 , wherein the retraction spring is guided by the carriage stop.