Devices, systems and methods for medicament delivery

Abstract

An apparatus includes a movable member and a valve coupled to the movable member. The movable member is configured to be disposed within a housing of a medical device and has a first end portion and second end portion. A portion of the first end portion is configured to define a portion of a boundary of a gas chamber. The first end portion defines an opening configured to be in fluid communication between the gas chamber and an area outside the gas chamber. The second end portion is configured to be coupled to a needle configured to deliver a medicament into a body. The valve is configured to selectively allow fluid communication between the gas chamber and the area outside the gas chamber through the opening defined by the first end portion of the movable member.

What is claimed is: 
     
         1 . An apparatus, comprising:
 a housing defining a gas chamber;   a medicament container disposed within the housing;   a needle fluidically coupled to the medicament container, the needle configured to move between a first needle position, in which the needle is disposed within the housing, and a second needle position in which a portion of the needle extends from the housing;   a retraction spring configured to bias the needle towards the first needle position;   an expandable assembly including a flexible member and a distal member, the flexible member configured to transition between a collapsed configuration and an expanded configuration; and   an energy storage member configured to produce a pressurized gas within the gas chamber, the pressurized gas exerting a force to move the needle from the first needle position to the second needle position and to move the distal member of the expandable assembly within the medicament container to convey a medicament from the medicament container via the needle, the flexible member of the expandable assembly configured to actuate a valve to release the pressurized gas from the gas chamber when the flexible member is transitioned from the collapsed configuration to the expanded configuration.   
     
     
         2 . The apparatus of  claim 1 , wherein the flexible member has a first size when in the collapsed configuration and a second size when in the expanded configuration, the flexible member being transitioned from the collapsed configuration to the expanded configuration when the distal member of the expandable assembly moves within the medicament container such that the flexible member actuates the valve after the medicament is conveyed from the medicament container. 
     
     
         3 . The apparatus of  claim 1 , wherein:
 a length of the flexible member increases when the distal portion of the expandable assembly moves within the medicament container to convey the medicament.   
     
     
         4 . The apparatus of  claim 3 , wherein:
 the flexible member transfers a tensile force from the distal portion to the valve to actuate the valve when the distal portion has moved the predetermined distance.   
     
     
         5 . The apparatus of  claim 1 , wherein the flexible member is one of a string, an elastic member or a biasing member. 
     
     
         6 . An apparatus, comprising:
 a housing defining a gas chamber;   a medicament container disposed within the housing;   a needle fluidically coupled to the medicament container, the needle configured to move between a first needle position, in which the needle is disposed within the housing, and a second needle position in which a portion of the needle extends from the housing;   a pusher configured to push the medicament from the medicament container and through the needle to convey the medicament out of the medicament container;   a retraction spring configured to bias the needle towards the first needle position;   a flexible release member having a proximal portion and a distal portion, the flexible release member configured to transition between a collapsed configuration and an expanded configuration; and   an energy storage member configured to produce a pressurized gas within the gas chamber, the pressurized gas exerting a force to move the needle from the first needle position to the second needle position and to move the pusher within the medicament container to convey a medicament from the medicament container via the needle—the flexible release member configured to actuate a valve to release the pressurized gas from the gas chamber when the flexible release member is transitioned from the collapsed configuration to the expanded configuration.   
     
     
         7 . The apparatus of  claim 6 , wherein the flexible release member has a first size when in the collapsed configuration and a second size when in the expanded configuration, the flexible release member being transitioned from the collapsed configuration to the expanded configuration when the distal portion of the expandable assembly moves within the medicament container such that the flexible release member actuates the valve after the medicament is conveyed from the medicament container. 
     
     
         8 . The apparatus of  claim 6 , wherein:
 a length of the flexible release member increases when the pusher moves within the medicament container to convey the medicament; and   the proximal portion of the flexible member is configured to actuate the valve when the distal portion of the flexible member moves a predetermined distance within the medicament container.   
     
     
         9 . The apparatus of  claim 6 , wherein:
 the flexible release member is a tension member; and   the tension member transfers a tensile force from the distal portion to the valve via the proximal portion to actuate the valve when the distal portion has moved the predetermined distance.   
     
     
         10 . The apparatus of  claim 6 , wherein:
 a length of the flexible release member increases when the pusher moves within the medicament container to convey the medicament;   the retraction spring causes the needle to move from the second needle position towards the first needle position after the pressurized gas is released from the gas chamber; and   the length of the flexible release member decreases when the needle moves from the second position towards the first needle position.   
     
     
         11 . A method of delivering a medicament from a medical injector, comprising:
 moving an actuator of a medical injector relative to a housing of the medical injector, the medical injector including a housing, a medicament container within the housing, a plunger within the medicament container, a needle fluidically coupled to the medicament container, an energy storage member, a valve, and a flexible member coupled between the plunger and the valve;   producing, from the energy storage member in response to the moving the actuator, a pressurized gas within a gas chamber defined by the housing;   moving, in response to the pressurized gas, the needle from a first needle position, in which the needle is within the housing, to a second needle position, in which a portion of the needle is outside of the housing;   moving, in response to the pressurized gas, the plunger within the medicament container to convey the medicament from the medicament container via the needle;   transitioning the flexible member from a first configuration to a second configuration when the plunger moves within the medicament container;   actuating the valve to release the pressurized gas from the gas chamber when the flexible member is transitioned from the first configuration to the second configuration; and   
     
     
         12 . The method of  claim 11 , wherein the medical injector includes a retraction spring, the method further comprising:
 moving the needle towards the first needle position after the pressurized gas is released from the gas chamber.   
     
     
         13 . The method of  claim 11 , wherein the transitioning the flexible member includes increasing a length of the flexible member. 
     
     
         14 . The method of  claim 13 , wherein the flexible member is one of a string, an elastic member or a biasing member. 
     
     
         15 . The method of  claim 14 , wherein:
 a portion of the valve is within a vent opening defined by the housing to fluidically isolate the gas chamber from an external volume;   the actuating the valve includes moving the portion of the valve out of the vent opening to place the gas chamber in fluid communication with the external volume.   
     
     
         16 . The method of  claim 15 , wherein the medical injector includes a cover disposed about the opening, the cover configured to limit access to the opening from the external volume. 
     
     
         17 . The method of  claim 14 , wherein:
 a proximal end portion of the flexible member is coupled to the valve; and   the length of the expandable assembly increases when the plunger moves within the medicament container, the proximal end portion of the flexible member actuating the valve when the plunger moves a predetermined distance within the medicament container.