In accordance with one embodiment, a controller in a fluid delivery system controls magnitudes of pressure in a first volume and a second volume. The first volume is of a known magnitude. The second volume is of an unknown magnitude and varies. The controller estimates a temperature of gas in the first volume and a temperature of gas in the second volume based on measurements of pressure in the first volume and measurements of pressure in the second volume. The controller then calculates a magnitude of the second volume based on measured pressures of the gases and estimated temperatures of gases in the first volume and the second volume.

In various embodiments, a drug pump includes a housing and, within the housing, an expandable drug reservoir at least part of which is exposed to a pressurized propellant. The propellant exerts a substantially constant pressure on the drug reservoir. A flow restrictor significantly limits outflow from the pump, and preferably has both a small diameter and a long path length, which acts to control the outflow from the drug reservoir. As a result, the pump produces a substantially constant outflow.

An orientation independent delivery device. The delivery device includes a gas chamber, a delivery chamber, a gas cell, and a delivery aperture. The gas chamber includes a gas-side rigid portion and a gas-side flexible barrier. The gas-side flexible barrier is sealed to the gas-side rigid portion. The delivery chamber includes a delivery-side rigid portion and a delivery-side flexible barrier. The delivery-side flexible barrier is sealed to the delivery-side rigid portion and is oriented adjacent to the gas-side flexible barrier. The gas cell is coupled to the gas-side rigid portion of the gas chamber. The gas cell increases a gas pressure within the gas chamber to expand the gas-side flexible barrier. Expansion of the gas-side flexible barrier applies a compressive force to the delivery-side flexible barrier allowing a delivery material to escape from the delivery chamber.

A multi-site injection system includes a plurality of medicament delivering needles/microprotrusions, a needle/microprotrusion support, a supply of medicament, and a mechanism for providing the medicament to the plurality of needles/microprotrusions in order to effect delivery into a stratum corneum of a user.

Embodiments of the present invention provide a vent arrangement integrated with a refill port disposed on the outer shell of an implantable drug-delivery device. The vent arrangement may utilize a tiered structure with two septums in a space-efficient configuration that facilitates both venting of pressure and refill of the drug reservoir.

The present invention discloses a liquid medicine injection device that is attached to a patient's body to inject liquid medicine such as insulin at an appropriate time.

A liquid medicine injection device according to the present invention includes: a case; a liquid medicine tank that is disposed in the case and where liquid medicine is received; an electro-osmosis pump that is connected with the liquid medicine tank and moves the liquid medicine; a needle assembly that receives the liquid medicine by being connected to the electro-osmosis pump and injects the received liquid medicine into a human body; and an adhesive member combined to the case and attached to the human body.

The present invention discloses a path-type liquid medicine delivery electro-osmosis pump that can be applied to a wearable medicine device.

An electro osmosis pump according to the present invention includes: a connector provided with a liquid medicine inlet and a liquid medicine outlet; a check valve assembly combined to one side of the connector; and a driver that is connected to the other side of the connector and moves the liquid medicine toward the liquid medicine outlet by applying pressure to the liquid medicine while being separated from the liquid medicine, which passes through the check valve assembly.

A controller controls a fluid pump to deliver primary fluid from a first source at a desired rate through a respective conduit to a recipient. The controller monitors a volume of the primary fluid injected into the conduit. Subsequent to injecting a predetermined amount of the primary fluid into the conduit, the controller i) discontinues injection of the primary fluid into the conduit and ii) injects a secondary fluid through the conduit to advance a remaining portion of the primary fluid in the conduit to the recipient. The controller advances the secondary fluid into the conduit until a desired amount of the primary fluid is delivered trough the conduit to the recipient. Injection of the secondary fluid to push the remaining portion of the primary fluid reduces waste associated with the primary fluid.

In various embodiments, approaches to calibrating an implantable drug-delivery device feature a drug reservoir, an expandable electrolysis chamber, and an integrated strain gauge using a refill apparatus having one or more pumps, one or more refill reservoirs, an outlet fluid channel fluidically connected to the refill reservoir(s), and a needle having a lumen in fluid communication with the outlet fluid channel include inserting a needle into a refill port of the implantable drug-delivery device, monitoring a pressure change within the device, monitoring a pressure level of one or more components of the implantable drug-delivery device, and calibrating the monitored pressure level of the component(s) of the implantable drug-delivery device to the monitored pressure level of the outlet fluid channel.

A method of operating an infusion device that includes the steps of actuating a fluid transfer device, which is configured to deliver a predetermined volume during each actuation, in accordance with a delivery profile that includes a plurality of fluid transfer device actuations, determining, based on sensed pressure, whether an actual volume delivered during a fluid transfer device actuation is the predetermined volume, and adjusting the number of actuations in the delivery profile in response to the actual volume delivered differing from the predetermined volume.