Injection devices and methods for making and using them

A drive module for a medical device, comprising:

• an elongate drive housing including a first end and a second end defining a longitudinal axis therebetween, a first chamber adjacent the first end communicating with a second chamber adjacent the second end via an intermediate passage;
• a canister containing pressurized gas including a penetrable septum within the first chamber;
• a pin holder carrying a puncture pin within the drive housing adjacent the canister, the pin holder movable axially from an inactive position wherein the puncture pin is spaced apart from the septum and an active position wherein the puncture pin penetrates the septum, the pin holder biased to the active position;
• one or more catches on the drive housing adjacent the pin holder;
• and
• an actuation sleeve slidably disposed within the drive housing at least partially around the canister, the actuation sleeve movable from a first position wherein the one or more catches restrain the pin holder in the inactive position to a second position wherein the one or more catches are disengaged to release the pin holder, whereupon the pin holder automatically moves from the inactive position to the active position to penetrate the septum and cause the gas within the canister to flow through the first chamber around the canister, through the intermediate passage, and into the second chamber to power the drive module.

A medical device, comprising:

• a) a drive module comprising:
• an elongate drive housing including a first end and a second end defining a longitudinal axis therebetween, a first chamber adjacent the first end communicating with a second chamber adjacent the second end via an intermediate passage;
• a canister containing pressurized gas including a penetrable septum within the first chamber;
• a pin holder carrying a puncture pin within the drive housing adjacent the canister, the pin holder movable axially from an inactive position wherein the puncture pin is spaced apart from the septum and an active position wherein the puncture pin penetrates the septum, the pin holder biased to the active position;
• one or more catches on the drive housing adjacent the pin holder for restraining the pin holder in the inactive position;
• and
• an actuation sleeve slidably disposed within the drive housing and comprising one or more actuation elements spaced apart from to the one or more catches in a first position, the actuation sleeve directable to a second position such that the one or more actuation elements disengage the one or more catches to release the pin holder, whereupon the pin holder automatically moves from the inactive position to the active position to penetrate the septum and cause the gas within the canister to flow through the first chamber around the canister, through the intermediate passage, and into the second chamber to power the drive module;
• b) a patient treatment module comprising:
• a housing coupled to the second end of the drive housing;
• and
• a device powered by the gas from the canister delivered into the second chamber.