Systems and methods allowing for reservoir air bubble management

Various embodiments of the present invention are directed to limiting a presence of air bubbles in a fluidic medium expelled from a reservoir. In various embodiments, a plunger head within a reservoir is shaped so as to limit a presence of air bubbles in a fluidic medium expelled from the reservoir. Also, in various embodiments, a reservoir is shaped so as to limit a presence of air bubbles in a fluidic medium expelled from the reservoir. In some embodiments, both a reservoir and a plunger head within the reservoir are shaped so as to limit a presence of air bubbles in a fluidic medium expelled from the reservoir.

BACKGROUND OF THE INVENTION

1. Field of the Invention

Embodiments of the present invention relate generally to systems and methods with reservoirs and, in specific embodiments, to a system with a reservoir and a plunger that are shaped to limit a presence of air bubbles in a fluidic medium expelled from the reservoir.

2. Related Art

According to modern medical techniques, certain chronic diseases may be treated by delivering a medication or other substance to the body of a patient. For example, diabetes is a chronic disease that is commonly treated by delivering defined amounts of insulin to a patient at appropriate times. Traditionally, manually operated syringes and insulin pens have been employed for delivering insulin to a patient. More recently, modern systems have been designed to include programmable pumps for delivering controlled amounts of medication to a patient.

Pump type delivery devices have been configured in external devices, which connect to a patient, and have also been configured in implantable devices, which are implanted inside of the body of a patient. External pump type delivery devices include devices designed for use in a stationary location, such as a hospital, a clinic, or the like, and further include devices configured for ambulatory or portable use, such as devices that are designed to be carried by a patient, or the like. External pump type delivery devices may be connected in fluid flow communication to a patient or user, for example, through a suitable hollow tubing. The hollow tubing may be connected to a hollow needle that is designed to pierce the skin of the patient and to deliver a fluidic medium there-through. Alternatively, the hollow tubing may be connected directly to the patient as through a cannula, or the like.

Examples of some external pump type delivery devices are described in the following references: (i) Published PCT Application WO 01/70307 (PCT/US01/09139), entitled “Exchangeable Electronic Cards for Infusion Devices”; (ii) Published PCT Application WO 04/030716 (PCT/US2003/028769), entitled “Components and Methods for Patient Infusion Device”; (iii) Published PCT Application WO 04/030717 (PCT/US2003/029019), entitled “Dispenser Components and Methods for Infusion Device”; (iv) U.S. Patent Application Pub. No. 2005/0065760, entitled “Method for Advising Patients Concerning Doses Of Insulin”; and (v) U.S. Pat. No. 6,589,229, entitled “Wearable Self-Contained Drug Infusion Device”, each of which is incorporated by reference herein in its entirety.

As compared to syringes and insulin pens, pump type delivery devices can be significantly more convenient to a patient, in that doses of insulin may be calculated and delivered automatically to a patient at any time during the day or night. Furthermore, when used in conjunction with glucose sensors or monitors, insulin pumps may be automatically controlled to provide appropriate doses of a fluidic medium at appropriate times of need, based on sensed or monitored levels of blood glucose. As a result, pump type delivery devices have become an important aspect of modern medical treatments of various types of medical conditions, such as diabetes, and the like. As pump technologies improve and doctors and patients become more familiar with such devices, external medical infusion pump treatments are expected to increase in popularity and are expected to increase substantially in number over the next decade.

SUMMARY OF THE DISCLOSURE

Various embodiments of the present invention are directed to limiting a presence of air bubbles in a fluidic medium expelled from a reservoir. In various embodiments, a plunger head within a reservoir is shaped so as to limit a presence of air bubbles in a fluidic medium expelled from the reservoir. Also, in various embodiments, a reservoir is shaped so as to limit a presence of air bubbles in a fluidic medium expelled from the reservoir. In some embodiments, both a reservoir and a plunger head within the reservoir are shaped so as to limit a presence of air bubbles in a fluidic medium expelled from the reservoir.

A plunger head in accordance with an embodiment of the present invention is moveable within a reservoir. In various embodiments, the plunger head is shaped to form a bubble trap region for trapping air bubbles that are in a fluidic medium as the fluidic medium is expelled from the reservoir by the plunger head. In some embodiments, the plunger head has a concave portion that defines the bubble trap region.

In various embodiments, the plunger head includes a body portion, a first protrusion portion protruding from the body portion, and a second protrusion portion protruding from the body portion, where the bubble trap region is located between the first protrusion portion and the second protrusion portion. In some embodiments, the first protrusion portion surrounds at least a portion of the second protrusion portion. Also, in some embodiments, the first protrusion portion extends a first distance from the body portion, the second protrusion portion extends a second distance from the body portion, and the first distance is greater than the second distance. In some embodiments, the second distance is greater than one-fourth of the first distance. Also, in some embodiments, the second protrusion portion includes a cavity for receiving a portion of a needle.

In various embodiments, the plunger head includes a curved surface that defines the bubble trap region, where the curved surface has a first end position, a second end position, and an innermost position. In further embodiments, a depth of the bubble trap region is at least greater than one-half of a width of the bubble trap region from the first end position to the second end position.

A system for delivering a fluidic medium in accordance with an embodiment of the present invention includes a reservoir and a plunger head. In various embodiments, the reservoir includes a reservoir body portion having an interior volume for containing the fluidic medium, and a port in fluid flow communication with the interior volume. Also, in various embodiments, the plunger head is moveable within the reservoir, and the plunger head is shaped to form a bubble trap region for trapping air bubbles that are in the fluidic medium as the fluidic medium is being expelled from the interior volume through the port by the plunger head. In some embodiments, the plunger head has a concave portion that defines the bubble trap region.

In various embodiments, the plunger head includes a body portion, a first protrusion portion protruding from the body portion, and a second protrusion portion protruding from the body portion, where the bubble trap region is located between the first protrusion portion and the second protrusion portion. In some embodiments, the first protrusion portion surrounds at least a portion of the second protrusion portion. In some embodiments, the first protrusion portion extends a first distance from the body portion, the second protrusion portion extends a second distance from the body portion, and the first distance is greater than the second distance. Also, in some embodiments, the second distance is greater than one-fourth of the first distance. In various embodiments, the second protrusion portion is aligned with the port such that when a needle is inserted into the port, an end of the needle is directed toward the second protrusion portion. Also, in various embodiments, the second protrusion portion includes a cavity for receiving a portion of a needle.

In various embodiments, the reservoir further includes a reservoir bubble trap portion having a volume in fluid flow communication with the interior volume for trapping air bubbles that are in the fluidic medium as the fluidic medium is being expelled from the interior volume. In some embodiments, a contour of the first protrusion portion of the plunger head substantially matches an inner contour of the reservoir bubble trap portion. In various embodiments, the first protrusion portion of the plunger head is shaped and positioned such that the first protrusion portion extends at least partially into the volume of the reservoir bubble trap portion when the plunger head is sufficiently advanced within the reservoir. In some embodiments, the first protrusion portion of the plunger head is shaped and positioned such that when the plunger head is fully advanced within the reservoir the first protrusion portion substantially fills the volume of the reservoir bubble trap portion.

In various embodiments, the reservoir is shaped such that in order for the fluidic medium to flow from the volume of the reservoir bubble trap portion to the port, the fluidic medium must flow through the interior volume. In some embodiments, the reservoir includes a material for shunting air bubbles in the fluidic medium away from the port and toward the volume of the reservoir bubble trap portion when the fluidic medium is being expelled from the interior volume. In some embodiments, the reservoir further includes a channel that leads from the interior volume to the port. Also, in some embodiments, the reservoir bubble trap portion includes a first portion that extends from the reservoir body portion away from the interior volume, and a second portion that returns back toward the interior volume, where the reservoir bubble trap portion encircles at least a portion of the channel.

In various embodiments, the system further includes a drive device, a plunger arm, a disposable housing, and a durable housing. In some embodiments, the drive device includes a linkage portion and a motor for moving the linkage portion. In some embodiments, the plunger arm is connected to the plunger head, and the plunger arm has a mating portion for mating with the linkage portion of the drive device. In various embodiments, the disposable housing allows for housing the reservoir and for being secured to a user. Also, in various embodiments, the durable housing allows for housing the motor of the drive device, where the durable housing is configured to be selectively engaged with and disengaged from the disposable housing.

A method in accordance with an embodiment of the present invention allows for expelling a fluidic medium from a reservoir using a plunger head. In various embodiments, the plunger head has a concave portion that defines a bubble trap region. Also, in various embodiments, the method includes expelling the fluidic medium from the reservoir using the plunger head, and trapping, in the bubble trap region defined by the concave portion of the plunger head, air bubbles that are in the fluidic medium as the fluidic medium is being expelled from the reservoir by the plunger head.

A system in accordance with an embodiment of the present invention includes a reservoir and a plunger head. The plunger head is moveable within the reservoir and has a cavity for receiving at least a portion of a needle when the plunger head is sufficiently advanced within the reservoir and the portion of the needle is inserted into the reservoir. In various embodiments, the reservoir has a reservoir body portion and a neck portion. Also, in various embodiments, the plunger head has a plunger body portion and a plunger neck portion and the cavity is in the plunger neck portion.

In various embodiments, the system further includes a seal surrounding at least a part of the plunger body portion, where the seal is in contact with the reservoir body portion of the reservoir when the plunger body portion is within the reservoir body portion of the reservoir. Also, in various embodiments, the system further includes a septum positioned at an end of the neck portion of the reservoir, and the cavity of the plunger neck portion is located in a position such that the cavity receives the portion of the needle when the plunger head is sufficiently advanced within the reservoir and the needle pierces the septum.

In some embodiments, an opening of the cavity of the plunger neck portion is located approximately at a center of an end surface of the plunger head. Also, in some embodiments, a contour of an outer surface of the plunger neck portion substantially matches a contour of an inner surface of the neck portion of the reservoir. In various embodiments, a diameter of an outer surface of the plunger neck portion substantially matches a diameter of an inner surface of the neck portion of the reservoir.

In various embodiments, the reservoir further includes a sloped portion between the reservoir body portion and the neck portion, and the plunger head further includes a plunger sloped portion between the plunger body portion and the plunger neck portion. In some embodiments, the system further includes a septum positioned at an end of the neck portion of the reservoir, and a length of the plunger neck portion from an end of the plunger neck portion to the plunger sloped portion substantially matches a length of the neck portion of the reservoir from the septum to the sloped portion of the reservoir. Also, in some embodiments, the cavity of the plunger neck portion extends into the plunger neck portion a distance that is greater than one-fourth of the length of the plunger neck portion.

In various embodiments, the plunger neck portion is shaped such that the plunger neck portion substantially fills an area within the neck portion of the reservoir when the plunger head is fully advanced within the reservoir. In some embodiments, the system further includes a drive device including a linkage portion and a motor for moving the linkage portion, and a plunger arm connected to the plunger head, where the plunger arm has a mating portion for mating with the linkage portion of the drive device. Also, in some embodiments, the system further includes a disposable housing for housing the reservoir and for being secured to a user, and a durable housing for housing the motor of the drive device, where the durable housing is configured to be selectively engaged with and disengaged from the disposable housing.

A method in accordance with an embodiment of the present invention includes piercing a septum of a reservoir with a needle, and moving a plunger head within the reservoir such that at least a portion of the needle is received within a cavity of the plunger head. In some embodiments, the moving includes moving the plunger head within the reservoir such that a plunger neck portion of the plunger head extends into a neck portion of the reservoir. Also, in some embodiments, the moving includes moving the plunger head within the reservoir such that a portion of the plunger head contacts a portion of the septum.

In various embodiments, the method further includes retracting the plunger head within the reservoir to allow a fluidic medium to flow through the needle and into the reservoir. Also, in various embodiments, the method further includes removing the needle from the reservoir, piercing the septum of the reservoir with another needle, and moving the plunger head within the reservoir until at least a portion of the another needle is received within the cavity of the plunger head, so as to expel the fluidic medium from the reservoir through the another needle.

A system in accordance with another embodiment of the present invention includes a reservoir. The reservoir includes a reservoir body portion, a port, and a bubble trap portion. The reservoir body portion has an interior volume for containing a fluidic medium. The port is in fluid flow communication with the interior volume. The bubble trap portion has a volume in fluid flow communication with the interior volume for trapping air bubbles that are in the fluidic medium as the fluidic medium is being expelled from the interior volume.

In various embodiments, the port is located to a particular side of the interior volume, and the bubble trap portion is located to the particular side of the interior volume. In some embodiments, the bubble trap portion has a first portion that extends from the reservoir body portion away from the interior volume, and a second portion that returns back toward the interior volume. In various embodiments, the reservoir body portion and the bubble trap portion are a single seamless unit.

In some embodiments, the bubble trap portion has a first portion that extends from the reservoir body portion away from the interior volume, and a second portion that extends from the first portion toward the interior volume. Also, in some embodiments, the bubble trap portion includes a curved surface, and the curved surface has a first end region, a second end region, and a middle region between the first end region and the second end region. In further embodiments, the first end region and the second end region are closer to the interior volume than the middle region. Also, in further embodiments, the first end region is in contact with the reservoir body portion, and the second end region is located adjacent to the interior volume of the reservoir body portion.

In various embodiments, the bubble trap portion is shaped approximately as a semi-toroid. Also, in various embodiments, a surface of the bubble trap portion that is in contact with the fluidic medium when the fluidic medium is in the volume of the bubble trap portion is approximately U-shaped. In some embodiments, the bubble trap portion includes a first surface that defines an edge of the volume of the bubble trap portion, and a second surface that defines another edge of the volume of the bubble trap portion, where the second surface is positioned at an angle with respect to the first surface. In further embodiments, the angle between the first surface and the second surface is less than 90 degrees. Also, in further embodiments, the first surface is planar with respect to an inner surface of the reservoir body portion.

In various embodiments, the port is located to a particular side of the interior volume, and a first portion of the bubble trap portion extends from the reservoir body portion to the particular side. In further embodiments, the first portion is curved, and a second portion of the bubble trap portion extends from an end of the first portion toward the interior volume. In some embodiments, the reservoir is shaped such that in order for the fluidic medium to flow from the volume of the bubble trap portion to the port, the fluidic medium must flow through the interior volume. Also, in some embodiments, the reservoir further includes a channel that leads from the interior volume to the port, and the bubble trap portion encircles at least a portion of the channel.

In various embodiments, the system further includes a plunger head having a plunger body portion and a plunger protruding portion, where the plunger head is moveable within the reservoir. In further embodiments, a contour of the plunger protruding portion substantially matches an inner contour of the bubble trap portion. In some embodiments, the plunger protruding portion has a size such that when the plunger head is fully advanced within the reservoir the plunger protruding portion substantially fills the volume of the bubble trap portion. Also, in some embodiments, the plunger protruding portion fills less than all of the volume of the bubble trap portion when the plunger head is fully advanced within the reservoir, so that one or more air pockets for holding air exist between the plunger protruding portion and an inner surface of the bubble trap portion when the plunger head is fully advanced within the reservoir.

In various embodiments, the plunger protruding portion extends at least partially into the volume of the bubble trap portion when the plunger head is sufficiently advanced within the reservoir. Also, in various embodiments the system further includes a plunger head moveable within the reservoir, where the plunger head has a relief for receiving at least a portion of a needle when the plunger head is sufficiently advanced within the reservoir and the portion of the needle is inserted into the reservoir. In some embodiments, the reservoir includes at least one of a hydrophobic material and a hydrophilic material on at least part of a surface of the bubble trap portion. Also, in some embodiments, the reservoir includes a material for shunting air bubbles in the fluidic medium away from the port and toward the volume of the bubble trap portion when the fluidic medium is being expelled from the interior volume.

In various embodiments, the system further includes a plunger head moveable within the reservoir, a drive device including a linkage portion and a motor for moving the linkage portion, and a plunger arm connected to the plunger head, where the plunger arm has a mating portion for mating with the linkage portion of the drive device. Also, in various embodiments, the system includes a disposable housing for housing the reservoir and for being secured to a user, and a durable housing for housing the motor of the drive device, where the durable housing is configured to be selectively engaged with and disengaged from the disposable housing.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1illustrates a generalized representation of a system10in accordance with an embodiment of the present invention. The system10includes a delivery device12. The system10may further include a sensing device14, a command control device (CCD)16, and a computer18. In various embodiments, the delivery device12and the sensing device14may be secured at desired locations on the body5of a patient or user7. The locations at which the delivery device12and the sensing device14are secured to the body5of the user7inFIG. 1are provided only as representative, non-limiting, examples.

The delivery device12is configured to deliver a fluidic medium to the body5of the user7. In various embodiments, the fluidic medium includes a liquid, a fluid, a gel, or the like. In some embodiments, the fluidic medium includes a medicine or a drug for treating a disease or a medical condition. For example, the fluidic medium may include insulin for treating diabetes, or may include a drug for treating pain, cancer, a pulmonary disorder, HIV, or the like. In some embodiments, the fluidic medium includes a nutritional supplement, a dye, a tracing medium, a saline medium, a hydration medium, or the like.

The sensing device14includes a sensor, a monitor, or the like, for providing sensor data or monitor data. In various embodiments, the sensing device14may be configured to sense a condition of the user7. For example, the sensing device14may include electronics and enzymes reactive to a biological condition, such as a blood glucose level, or the like, of the user7. In various embodiments, the sensing device14may be secured to the body5of the user7or embedded in the body5of the user7at a location that is remote from the location at which the delivery device12is secured to the body5of the user7. In various other embodiments, the sensing device14may be incorporated within the delivery device12.

Each of the delivery device12, the sensing device14, the CCD16, and the computer18may include transmitter, receiver, or transceiver electronics that allow for communication with other components of the system10. The sensing device14may be configured to transmit sensor data or monitor data to the delivery device12. The sensing device14may also be configured to communicate with the CCD16. The delivery device12may include electronics and software that are configured to analyze sensor data and to deliver the fluidic medium to the body5of the user7based on the sensor data and/or preprogrammed delivery routines.

The CCD16and the computer18may include electronics and other components configured to perform processing, delivery routine storage, and to control the delivery device12. By including control functions in the CCD16and/or the computer18, the delivery device12may be made with more simplified electronics. However, in some embodiments, the delivery device12may include all control functions, and may operate without the CCD16and the computer18. In various embodiments, the CCD16may be a portable electronic device. Also, in various embodiments, the delivery device12and/or the sensing device14may be configured to transmit data to the CCD16and/or the computer18for display or processing of the data by the CCD16and/or the computer18. Examples of the types of communications and/or control capabilities, as well as device feature sets and/or program options may be found in the following references: (i) U.S. patent application Ser. No. 10/445,477, filed May 27, 2003, entitled “External Infusion Device with Remote Programming, Bolus Estimator and/or Vibration Alarm Capabilities”; (ii) U.S. patent application Ser. No. 10/429,385, filed May 5, 2003, entitled “Handheld Personal Data Assistant (PDA) with a Medical Device and Method of Using the Same”; and (iii) U.S. patent application Ser. No. 09/813,660, filed Mar. 21, 2001, entitled “Control Tabs for Infusion Devices and Methods of Using the Same”, all of which are incorporated herein by reference in their entirety.

FIG. 2illustrates an example of the system10in accordance with an embodiment of the present invention. The system10in accordance with the embodiment illustrated inFIG. 2includes the delivery device12and the sensing device14. The delivery device12in accordance with an embodiment of the present invention includes a disposable housing20, a durable housing30, and a reservoir40. The delivery device12may further include an infusion path50.

Elements of the delivery device12that ordinarily contact the body of a user or that ordinarily contact a fluidic medium during operation of the delivery device12may be considered as a disposable portion of the delivery device12. For example, a disposable portion of the delivery device12may include the disposable housing20and the reservoir40. The disposable portion of the delivery device12may be recommended for disposal after a specified number of uses.

On the other hand, elements of the delivery device12that do not ordinarily contact the body of the user or the fluidic medium during operation of the delivery device12may be considered as a durable portion of the delivery device12. For example, a durable portion of the delivery device12may include the durable housing30, electronics (not shown inFIG. 2), a drive device having a motor and drive linkage (not shown inFIG. 2), and the like. Elements of the durable housing portion of the delivery device12are typically not contaminated from contact with the user or the fluidic medium during normal operation of the delivery device12and, thus, may be retained for re-use with replaced disposable portions of the delivery device12.

In various embodiments, the disposable housing20supports the reservoir40and has a bottom surface (facing downward and into the page inFIG. 2) that is configured to secure to the body of a user. An adhesive may be employed at an interface between the bottom surface of the disposable housing20and the skin of a user, so as to adhere the disposable housing20to the skin of the user. In various embodiments, the adhesive may be provided on the bottom surface of the disposable housing20, with a peelable cover layer covering the adhesive material. In this manner, the cover layer may be peeled off to expose the adhesive material, and the adhesive side of the disposable housing20may be placed against the skin of the user.

The reservoir40is configured for containing or holding a fluidic medium, such as, but not limited to insulin. In various embodiments, the reservoir40includes a hollow interior volume for receiving the fluidic medium, such as, but not limited to, a cylinder-shaped volume, a tubular-shaped volume, or the like. In some embodiments, the reservoir40may be provided as a cartridge or canister for containing a fluidic medium. In various embodiments, the reservoir40is able to be refilled with a fluidic medium.

The reservoir40may be supported by the disposable housing20in any suitable manner. For example, the disposable housing20may be provided with projections or struts (not shown), or a trough feature (not shown), for holding the reservoir40. In some embodiments, the reservoir40may be supported by the disposable housing20in a manner that allows the reservoir40to be removed from the disposable housing20and replaced with another reservoir. Alternatively, or in addition, the reservoir40may be secured to the disposable housing20by a suitable adhesive, a strap, or other coupling structure.

In various embodiments, the reservoir40includes a port41for allowing a fluidic medium to flow into and/or flow out of the interior volume of the reservoir40. In some embodiments, the infusion path50includes a connector56, a tube54, and a needle apparatus52. The connector56of the infusion path50may be connectable to the port41of the reservoir40. In various embodiments, the disposable housing20is configured with an opening near the port41of the reservoir40for allowing the connector56of the infusion path50to be selectively connected to and disconnected from the port41of the reservoir40.

In various embodiments, the port41of the reservoir40is covered with or supports a septum (not shown inFIG. 2), such as a self-sealing septum, or the like. The septum may be configured to prevent a fluidic medium from flowing out of the reservoir40through the port41when the septum is not pierced. Also, in various embodiments, the connector56of the infusion path50includes a needle for piercing the septum covering the port41of the reservoir40so as to allow the fluidic medium to flow out of the interior volume of the reservoir40. Examples of needle/septum connectors can be found in U.S. patent application Ser. No. 10/328,393, filed Dec. 22, 2003, entitled “Reservoir Connector”, which is incorporated herein by reference in its entirety. In other alternatives, non-septum connectors such as Luer locks, or the like may be used. In various embodiments, the needle apparatus52of the infusion path50includes a needle that is able to puncture the skin of a user. Also, in various embodiments, the tube54connects the connector56with the needle apparatus52and is hollow, such that the infusion path50is able to provide a path to allow for the delivery of a fluidic medium from the reservoir40to the body of a user.

The durable housing30of the delivery device12in accordance with various embodiments of the present invention includes a housing shell configured to mate with and secure to the disposable housing20. The durable housing30and the disposable housing20may be provided with correspondingly shaped grooves, notches, tabs, or other suitable features, that allow the two parts to easily connect together, by manually pressing the two housings together, by twist or threaded connection, or other suitable manner of connecting the parts that is well known in the mechanical arts. In various embodiments, the durable housing30and the disposable housing20may be connected to each other using a twist action. The durable housing30and the disposable housing20may be configured to be separable from each other when a sufficient force is applied to disconnect the two housings from each other. For example, in some embodiments the disposable housing20and the durable housing30may be snapped together by friction fitting. In various embodiments, a suitable seal, such as an o-ring seal, may be placed along a peripheral edge of the durable housing30and/or the disposable housing20, so as to provide a seal against water entering between the durable housing30and the disposable housing20.

The durable housing30of the delivery device12may support a drive device (not shown inFIG. 2), including a motor and a drive device linkage portion, for applying a force to the fluidic medium within the reservoir40to force the fluidic medium out of the reservoir40and into an infusion path, such as the infusion path50, for delivery to a user. For example, in some embodiments, an electrically driven motor may be mounted within the durable housing30with appropriate linkage for operatively coupling the motor to a plunger arm (not shown inFIG. 2) connected to a plunger head (not shown inFIG. 2) that is within the reservoir40and to drive the plunger head in a direction to force the fluidic medium out of the port41of the reservoir40and to the user. Also, in some embodiments, the motor may be controllable to reverse direction so as to move the plunger arm and the plunger head to cause fluid to be drawn into the reservoir40from a patient. The motor may be arranged within the durable housing30and the reservoir40may be correspondingly arranged on the disposable housing20, such that the operable engagement of the motor with the plunger head, through the appropriate linkage, occurs automatically upon the user connecting the durable housing30with the disposable housing20of the delivery device12. Further examples of linkage and control structures may be found in U.S. patent application Ser. No. 09/813,660, filed Mar. 21, 2001, entitled “Control Tabs for Infusion Devices and Methods of Using the Same”, which is incorporated herein by reference in its entirety.

In various embodiments, the durable housing30and the disposable housing20may be made of suitably rigid materials that maintain their shape, yet provide sufficient flexibility and resilience to effectively connect together and disconnect, as described above. The material of the disposable housing20may be selected for suitable compatibility with skin. For example, the disposable housing20and the durable housing30of the delivery device12may be made of any suitable plastic, metal, composite material, or the like. The disposable housing20may be made of the same type of material or a different material relative to the durable housing30. In some embodiments, the disposable housing20and the durable housing30may be manufactured by injection molding or other molding processes, machining processes, or combinations thereof.

For example, the disposable housing20may be made of a relatively flexible material, such as a flexible silicone, plastic, rubber, synthetic rubber, or the like. By forming the disposable housing20of a material capable of flexing with the skin of a user, a greater level of user comfort may be achieved when the disposable housing20is secured to the skin of the user. Also, a flexible disposable housing20may result in an increase in site options on the body of the user at which the disposable housing20may be secured.

In the embodiment illustrated inFIG. 2, the delivery device12is connected to the sensing device14through a connection element16of the sensing device14. The sensing device14may include a sensor15that includes any suitable biological or environmental sensing device, depending upon a nature of a treatment to be administered by the delivery device12. For example, in the context of delivering insulin to a diabetes patient, the sensor15may include a blood glucose sensor, or the like.

The sensor15may be an external sensor that secures to the skin of a user or, in other embodiments, may be an implantable sensor that is located in an implant site within the body of the user. In further alternatives, the sensor may be included with as a part or along side the infusion cannula and/or needle, such as for example as shown in U.S. patent application Ser. No. 11/149,119, filed Jun. 8, 2005, entitled “Dual Insertion Set”, which is incorporated herein by reference in its entirety. In the illustrated example ofFIG. 2, the sensor15is an external sensor having a disposable needle pad that includes a needle for piercing the skin of the user and enzymes and/or electronics reactive to a biological condition, such as blood glucose level or the like, of the user. In this manner, the delivery device12may be provided with sensor data from the sensor15secured to the user at a site remote from the location at which the delivery device12is secured to the user.

While the embodiment shown inFIG. 2includes a sensor15connected by the connection element16for providing sensor data to sensor electronics (not shown inFIG. 2) located within the durable housing30of the delivery device12, other embodiments may employ a sensor15located within the delivery device12. Yet other embodiments may employ a sensor15having a transmitter for communicating sensor data by a wireless communication link with receiver electronics (not shown inFIG. 2) located within the durable housing30of the delivery device12. In various embodiments, a wireless connection between the sensor15and the receiver electronics within the durable housing30of the delivery device12may include a radio frequency (RF) connection, an optical connection, or another suitable wireless communication link. Further embodiments need not employ the sensing device14and, instead, may provide fluidic medium delivery functions without the use of sensor data.

As described above, by separating disposable elements of the delivery device12from durable elements, the disposable elements may be arranged on the disposable housing20, while durable elements may be arranged within a separable durable housing30. In this regard, after a prescribed number of uses of the delivery device12, the disposable housing20may be separated from the durable housing30, so that the disposable housing20may be disposed of in a proper manner. The durable housing30may then be mated with a new (un-used) disposable housing20for further delivery operation with a user.

FIG. 3illustrates an example of the delivery device12in accordance with another embodiment of the present invention. The delivery device12of the embodiment ofFIG. 3is similar to the delivery device12of the embodiment ofFIG. 2. While the delivery device12in the embodiment illustrated inFIG. 2provides for the durable housing30to cover the reservoir40, the delivery device12in the embodiment ofFIG. 3provides for the durable housing30to secure to the disposable housing20without covering the reservoir40. The delivery device12of the embodiment illustrated inFIG. 3includes the disposable housing20, and the disposable housing20in accordance with the embodiment illustrated inFIG. 3includes a base21and a reservoir retaining portion24. In one embodiment, the base21and reservoir retaining portion24may be formed as a single, unitary structure.

The base21of the disposable housing20is configured to be secured to the body of a user. The reservoir retaining portion24of the disposable housing20is configured to house the reservoir40. The reservoir retaining portion24of the disposable housing20may be configured to have an opening to allow for the port41of the reservoir40to be accessed from outside of the reservoir retaining portion24while the reservoir40is housed in the reservoir retaining portion24. The durable housing30may be configured to be attachable to and detachable from the base21of the disposable housing20. The delivery device12in the embodiment illustrated inFIG. 3includes a plunger arm60that is connected to or that is connectable to a plunger head (not shown inFIG. 3) within the reservoir40.

FIG. 4illustrates another view of the delivery device12of the embodiment ofFIG. 3. The delivery device12of the embodiment illustrated inFIG. 4includes the disposable housing20, the durable housing30, and the infusion path50. The disposable housing20in the embodiment ofFIG. 4includes the base21, the reservoir retaining portion24, and a peelable cover layer25. The peelable cover layer25may cover an adhesive material on the bottom surface22of the base21. The peelable cover layer25may be configured to be peelable by a user to expose the adhesive material on the bottom surface22of the base21. In some embodiments, there may be multiple adhesive layers on the bottom surface22of the base21that are separated by peelable layers.

The infusion path50in accordance with the embodiment of the present invention illustrated inFIG. 4includes the needle58rather than the connector56, the tube54, and the needle apparatus52as shown in the embodiment ofFIG. 2. The base21of the disposable housing20may be provided with an opening or pierceable wall in alignment with a tip of the needle58, to allow the needle58to pass through the base21and into the skin of a user under the base21, when extended. In this manner, the needle58may be used to pierce the skin of the user and deliver a fluidic medium to the user.

Alternatively, the needle58may be extended through a hollow cannula (not shown inFIG. 4), such that upon piercing the skin of the user with the needle58, an end of the hollow cannula is guided through the skin of the user by the needle58. Thereafter, the needle58may be removed, leaving the hollow cannula in place, with one end of the cannula located within the body of the user and the other end of the cannula in fluid flow connection with the fluidic medium within the reservoir40, to convey pumped infusion media from the reservoir40to the body of the user.

FIG. 5Aillustrates a durable portion8of the delivery device12(refer toFIG. 3) in accordance with an embodiment of the present invention.FIG. 5Billustrates a section view of the durable portion8in accordance with an embodiment of the present invention.FIG. 5Cillustrates another section view of the durable portion8in accordance with an embodiment of the present invention. With reference toFIGS. 5A,5B, and5C, in various embodiments, the durable portion8includes the durable housing30, and a drive device80. The drive device80includes a motor84and a drive device linkage portion82. In various embodiments, the durable housing30may include an interior volume for housing the motor84, the drive device linkage portion82, other electronic circuitry, and a power source (not shown inFIGS. 5A,5B, and5C). Also, in various embodiments, the durable housing30is configured with an opening32for receiving a plunger arm60(refer to FIG.3). Also, in various embodiments, the durable housing30may include one or more connection members34, such as tabs, insertion holes, or the like, for connecting with the base21of the disposable housing20(refer toFIG. 3).

FIG. 6Aillustrates a disposable portion9of the delivery device12(refer toFIG. 3) in accordance with an embodiment of the present invention.FIG. 6Billustrates a section view of the disposable portion9in accordance with an embodiment of the present invention.FIG. 6Cillustrates another section view of the disposable portion9in accordance with an embodiment of the present invention. With reference toFIGS. 6A,6B, and6C, in various embodiments, the disposable portion9includes the disposable housing20, the reservoir40, the plunger arm60, and a plunger head70. In some embodiments, the disposable housing20includes the base21and the reservoir retaining portion24. In various embodiments, the base21includes a top surface23having one or more connection members26, such as tabs, grooves, or the like, for allowing connections with the one or more connection members34of embodiments of the durable housing30(refer toFIG. 5B).

In various embodiments, the reservoir40is housed within the reservoir retaining portion24of the disposable housing20, and the reservoir40is configured to hold a fluidic medium. Also, in various embodiments, the plunger head70is disposed at least partially within the reservoir40and is moveable within the reservoir40to allow the fluidic medium to fill into the reservoir40and to force the fluidic medium out of the reservoir40. In some embodiments, the plunger arm60is connected to or is connectable to the plunger head70. Also, in some embodiments, a portion of the plunger arm60extends to outside of the reservoir retaining portion24of the disposable housing20. In various embodiments, the plunger arm60has a mating portion for mating with the drive device linkage portion82of the drive device80(refer toFIG. 5C). With reference toFIGS. 5C and 6C, in some embodiments, the durable housing30may be snap fitted onto the disposable housing20, whereupon the drive device linkage portion82automatically engages the mating portion of the plunger arm60.

When the durable housing30and the disposable housing20are fitted together with the drive device linkage portion82engaging or mating with the plunger arm60, the motor84may be controlled to drive the drive device linkage portion82and, thus, move the plunger arm60to cause the plunger head70to move within the reservoir40. When the interior volume of the reservoir40is filled with a fluidic medium and an infusion path is provided from the reservoir40to the body of a user, the plunger head70may be moved within the reservoir40to force the fluidic medium from the reservoir40and into the infusion path, so as to deliver the fluidic medium to the body of the user.

In various embodiments, once the reservoir40has been sufficiently emptied or otherwise requires replacement, a user may simply remove the durable housing30from the disposable housing20, and replace the disposable portion9, including the reservoir40, with a new disposable portion having a new reservoir. The durable housing30may be connected to the new disposable housing of the new disposable portion, and the delivery device including the new disposable portion may be secured to the skin of a user. In various other embodiments, rather than replacing the entire disposable portion9every time the reservoir40is emptied, the reservoir40may be refilled with a fluidic medium. In some embodiments, the reservoir40may be refilled while remaining within the reservoir retaining portion24(refer toFIG. 6B) of the disposable housing20. Also, in various embodiments, the reservoir40may be replaced with a new reservoir (not shown), while the disposable housing20may be re-used with the new reservoir. In such embodiments, the new reservoir may be inserted into the disposable portion9.

With reference toFIGS. 3,5A,6B, and6C, in various embodiments, the delivery device12includes reservoir status circuitry (not shown), and the reservoir40includes reservoir circuitry (not shown). In various embodiments, the reservoir circuitry stores information such as, but not limited to, at least one of (i) an identification string identifying the reservoir40; (ii) a manufacturer of the reservoir40; (iii) contents of the reservoir40; and (iv) an amount of contents in the reservoir40. In some embodiments, the delivery device12includes the reservoir status circuitry (not shown), and the reservoir status circuitry is configured to read data from the reservoir circuitry when the reservoir40is inserted into the disposable portion9.

In various embodiments, the reservoir status circuitry is further configured to store data to the reservoir circuitry after at least some of the contents of the reservoir40have been transferred out of the reservoir40, so as to update information in the reservoir circuitry related to an amount of contents still remaining in the reservoir40. In some embodiments, the reservoir status circuitry is configured to store data to the reservoir circuitry, so as to update information in the reservoir circuitry related to an amount of contents still remaining in the reservoir40, when the reservoir40is inserted into the disposable portion9. In some embodiments, the delivery device12includes the reservoir status circuitry (not shown) and the reservoir40includes the reservoir circuitry (not shown), and the reservoir status circuitry selectively inhibits use of the delivery device12or selectively provides a warning signal based on information read by the reservoir status circuitry from the reservoir circuitry.

FIG. 7Aillustrates a cross-sectional view of a system100in accordance with an embodiment of the present invention. The system100includes a reservoir110, a plunger head120, a plunger arm130, and a septum140. In various embodiments, the system100further includes a needle150. In some embodiments, the system100may further include similar elements as elements of embodiments of the delivery device12(refer toFIGS. 2 and 3), in which case the reservoir110would correspond to the reservoir40(refer toFIGS. 2,3, and6C). In various embodiments, the reservoir110may be made of a material, such as but not limited to a suitable metal, plastic, ceramic, glass, composite material, or the like. In various embodiments, the plunger head120may be made of a suitably rigid material such as, but not limited to, metal, plastic, ceramic, glass, composite material, or the like. In various other embodiments, the plunger head120may be made of a compressible material such as, but not limited to, an elastically compressible plastic, rubber, silicone, or the like.

In various embodiments, the reservoir110includes a reservoir body portion111, a body headspace or neck portion112, and a curved or sloped portion117that connects the reservoir body portion111and the neck portion112. The reservoir110has an outer surface113and an inner surface114. The inner surface114of the reservoir110defines a hollow interior of the reservoir110, and the hollow interior of the reservoir110is able to contain a fluidic medium. The reservoir110further includes a port118at an end of the neck portion112, through which the fluidic medium may be filled into or expelled from the hollow interior of the reservoir110. The reservoir body portion111of the reservoir110may have any suitable shape and may have, for example, a cylinder shape, a tube shape, a barrel shape, a spherical shape, a shape with a rectangular cross-section, or the like. Similarly, the neck portion112of the reservoir110may have any suitable shape and may have, for example, a cylinder shape, a tube shape, a barrel shape, a spherical shape, a shape with a rectangular cross-section, or the like.

The plunger head120is located within the reservoir110, and is moveable in an axial direction of the reservoir110, to expand or contract an interior volume of the reservoir110in which a fluidic medium may be contained. The plunger head120is connected to the plunger arm130, such that movement of the plunger arm130in the axial direction of the reservoir110causes movement of the plunger head120in the axial direction of the reservoir110. The plunger head120includes a plunger body portion121, a plunger headspace or neck portion122, and a plunger curved or sloped portion123that connects the plunger body portion121and the plunger neck portion122. In various embodiments, the plunger head120further includes one or more seals125that surround a portion of the plunger body portion121.

The plunger body portion121is shaped such that a contour of an outer surface of the plunger body portion121substantially matches or is substantially the same as a contour of an inner surface of the reservoir body portion111of the reservoir110. In various embodiments, the plunger body portion121has a diameter that is slightly smaller than a diameter of the inner surface of the reservoir body portion111of the reservoir110, such that the plunger head120is able to slide within the reservoir110. In some embodiments, the one or more seals125on the plunger body portion121are in contact with the inner surface of the reservoir body portion111of the reservoir110when the plunger head120is within the reservoir110.

The plunger neck portion122is shaped such that a contour of an outer surface of the plunger neck portion122substantially matches or is substantially the same as a contour of an inner surface of the neck portion112of the reservoir110. In various embodiments, the plunger neck portion122has a diameter that is slightly smaller than a diameter of the inner surface of the neck portion112of the reservoir110, such that the plunger neck portion122is able to slide within the neck portion112of the reservoir110. In some embodiments, a diameter of an outer surface of the plunger neck portion122closely matches or substantially matches a diameter of an inner surface of the neck portion112of the reservoir110. Also, in some embodiments, the plunger neck portion122is shaped such that the plunger neck portion122substantially fills an area within the neck portion112of the reservoir110when the plunger head120is fully advanced within the reservoir110. The plunger sloped portion123is shaped such that a contour of an outer surface of the plunger sloped portion123substantially matches or is substantially the same as a contour of an inner surface of the sloped portion117of the reservoir110.

The septum140is located at the port118of the reservoir110. The septum140may be formed of a suitable material, such as, but not limited to, rubber, silicone rubber, polyurethane, or other materials that may be pierced by a needle and form a seal around a needle. The neck portion112has a certain length from an end of the sloped portion117to the septum140. In various embodiments, the plunger neck portion122has a length that is substantially the same as the certain length of the neck portion112of the reservoir110. In some such embodiments, the plunger neck portion122is able to extend substantially all of the way into the neck portion112of the reservoir110when the plunger head120is fully advanced within the reservoir110. Thus, in some embodiments, an end of the plunger neck portion122may be close to or in contact with the septum140when the plunger head120is fully advanced within the reservoir110. In various embodiments, a length of the plunger neck portion122from an end of the plunger neck portion122to the plunger sloped portion123substantially matches a length of the neck portion112of the reservoir110from the septum140to the sloped portion117of the reservoir110.

The septum140is able to be pierced by the needle150, such as to allow for a fluidic medium to be passed through the needle150and into the hollow interior of the reservoir110. In various embodiments, the plunger head120includes a hole or a channel or a relief or a cavity124that is able to accommodate a portion of the needle150when the plunger head120is sufficiently advanced within the reservoir110and the septum140is pierced by the needle150. The cavity124may have any suitable shape for accommodating a portion of the needle150, and may have, for example, a cylindrical shape, a tube shape with a half-sphere bottom, a shape with a rectangular cross-section, or the like. In various embodiments, a diameter of the cavity124is larger than a diameter of the needle150, such that an end of the needle150is able to fit within the cavity124.

In various embodiments, the cavity124is in the plunger neck portion122of the plunger head120. In some embodiments, a length of the cavity124in the plunger neck portion122in a direction from the septum140toward the plunger body portion121is greater than one-quarter of a length of the plunger neck portion122. Also, in some embodiments, the cavity124is positioned at a center of an end surface of the plunger neck portion122. In some embodiments, the cavity124is positioned off-center at an end surface of the plunger neck portion122. In various embodiments, an end of the neck portion112of the reservoir110partially covers the septum140, such that the needle150may only pierce the septum140in a location that is aligned with the cavity124of the plunger head120.

FIG. 8illustrates a flowchart for a method in accordance with an embodiment of the present invention. With reference toFIGS. 7A and 8, in various embodiments the method ofFIG. 8allows for filling the reservoir110with a fluidic medium and for expelling the fluidic medium from the reservoir110. In S10, the septum140of the reservoir110is pierced with the needle150, and the method continues to S11. In S11, the plunger head120is advanced within the reservoir110, such that at least a portion of the needle150is received within the cavity124of the plunger head120. For example, the plunger arm130may be driven by a motor (not shown inFIG. 7A) or by a force applied by a user to advance the plunger head120within the reservoir110. In various embodiments, moving the plunger head120includes moving the plunger head120within the reservoir110such that the plunger neck portion122extends at least partially into the neck portion112of the reservoir110(S12). Also, in various embodiments, moving the plunger head120includes moving the plunger head120within the reservoir110such that a portion of the plunger head120contacts a portion of the septum140(S13). In some embodiments, S10and S11are performed in a reverse order, such that the plunger head120is moved and then the septum140is pierced with the needle150.

When the plunger head120is sufficiently advanced within the reservoir110, a portion of the needle150may extend into the cavity124of the plunger neck portion122, which may allow the plunger neck portion122to extend substantially all the way to the septum140. As a consequence, a presence of air pockets between an end of the plunger head120and the septum140is able to be substantially limited or eliminated when the plunger head120is fully advanced within the reservoir110. Reducing air pockets between the plunger head120and the septum140prior to filling the reservoir110is beneficial, because it limits an amount of air bubbles that subsequently enter the fluidic medium when the fluidic medium is drawn into the reservoir110.

In various embodiments, the method then continues to S14. In S14, the plunger head120is retracted within the reservoir110to allow a fluidic medium to flow through the needle150and into the reservoir110. For example, the plunger arm130may be retracted by a motor (not shown inFIG. 7A) or by a pulling force exerted by a user to cause the plunger head120to retract within the reservoir110.FIG. 7Billustrates a cross-sectional view of the system100in accordance with an embodiment of the present invention when the plunger head120has been partially retracted within the reservoir110. By retracting the plunger head120within the reservoir110, the fluidic medium is able to pass through the needle150and into the hollow interior of the reservoir110. For example, one end of the needle150may be in the reservoir110, and another end of the needle150may be in a vial (not shown inFIG. 7B) or other container that stores the fluidic medium, and the fluidic medium may pass from the vial to the reservoir110through the needle150. In some embodiments, the needle150is part of a transfer guard or other similar device. Because an amount of air in the reservoir110was limited prior to filling the reservoir110, an amount of air bubbles in the fluidic medium is also limited when the fluidic medium is filled into the reservoir110. Limiting or reducing a presence of air bubbles in the fluidic medium is beneficial, because it limits an amount of air bubbles that are later expelled from the reservoir110into a patient or user, and thus helps to improve a delivery accuracy when delivering a specified amount of the fluidic medium to a user.

With reference toFIGS. 7A,7B, and8, the method ofFIG. 8may then continue to S15in which the needle150is removed from the reservoir110. In various embodiments, the septum140is a self-healing septum, and when the needle150is removed from the reservoir110and the septum140, the septum140closes such that the fluidic medium is contained within the reservoir110. The method may then continue to S16. In S16, the septum140of the reservoir110is pierced with another needle. For example, the septum140of the reservoir110may be pierced with a needle of a connector of an infusion path, such as a needle of the connector56(refer toFIG. 2) of the infusion path50(refer toFIG. 2). The method then continues to S17.

In S17, the plunger head120is advanced within the reservoir110until at least a portion of the another needle is received within the cavity of the plunger head120, so as to expel the fluidic medium from the reservoir110through the another needle.FIG. 7Aillustrates the system100when the plunger head120has been substantially fully advanced within the reservoir110. When the plunger head120is advanced within the reservoir110, the close fitting contour of the plunger head120to the interior surface of the reservoir110limits or reduces a volume of wasted fluidic medium that remains in the reservoir110. Thus, by having a plunger head120with a plunger neck portion122that is shaped to very closely fit within the neck portion112of the reservoir110when the plunger head120is fully advanced, a presence of air bubbles in a fluidic medium may be limited during filling of the reservoir110, and a volume of wasted fluidic medium may be reduced when the fluidic medium is expelled from the reservoir110. The method then ends in S18.

FIG. 7Cillustrates a cross-sectional view from a front direction of the plunger neck portion122of the plunger head120in accordance with an embodiment of the present invention. The plunger neck portion122includes the cavity124for accommodating a needle. In various embodiments, the cavity124is positioned substantially near a center of a face of the plunger neck portion122.FIG. 7Dillustrates a side view of the plunger head120in accordance with an embodiment of the present invention. The plunger head120includes the plunger body portion121, the plunger neck portion122, and the plunger sloped portion123. In various embodiments, the plunger body portion121includes one or more depressions or cavities126in which the one or more seals125(refer toFIG. 7A) may be placed.

FIGS. 9A,10A,11A,12A,12C,14A, and14B illustrate systems in accordance with various embodiments of the present invention that include reservoirs with geometries that allow for capturing air bubbles so as to reduce a number of air bubbles that are delivered with a fluidic medium. Such systems allow for air bubble management since they have bubble trapping shapes and, by reducing a number of air bubbles that are delivered with a fluidic medium, such systems may be able to improve a delivery accuracy when attempting to deliver a specified volume of the fluidic medium. Thus, such systems provide reservoir geometries that allow for capturing a greater amount of air bubbles than with standard reservoir geometries, so that the captured air bubbles remain in the reservoir and are not dispensed with the fluidic medium.

In some embodiments, the systems inFIGS. 9A,10A,11A,12A,12C,13A,14A, and14B may include similar elements as elements of embodiments of the delivery device12(refer toFIGS. 2 and 3), in which case the reservoirs in those systems would correspond to the reservoir40(refer toFIGS. 2,3, and6C). In various embodiments, reservoirs of the systems inFIGS. 9A,10A,11A,12A,12C,13A,14A, and14B may be made of a material, such as but not limited to a suitable metal, plastic, ceramic, glass, composite material, or the like. In various embodiments, the plunger heads of the systems in those figures may be made of a suitably rigid material such as, but not limited to, metal, plastic, ceramic, glass, composite material, or the like. In various other embodiments, the plunger heads in those systems may be made of a compressible material such as, but not limited to, an elastically compressible plastic, rubber, silicone, or the like.

FIG. 9Aillustrates a cross-sectional view of a system200in accordance with an embodiment of the present invention. The system200includes a reservoir210, a plunger head220, and a plunger arm230. The reservoir210includes a reservoir body portion211, a bubble trap portion212, and a port217. The reservoir210has an outer surface213and an inner surface214. The inner surface214of the reservoir210defines a hollow interior of the reservoir210, and the hollow interior of the reservoir210is able to contain a fluidic medium. The port217of the reservoir210allows for the fluidic medium to be filled into or expelled from the hollow interior of the reservoir210. The reservoir body portion211of the reservoir210may have any suitable shape, such as but not limited to, a cylinder shape, a tube shape, a barrel shape, a spherical shape, a shape with a rectangular cross-section, or the like.

The plunger head220is located within the reservoir210, and is moveable in an axial direction of the reservoir210, to expand or contract a volume of the reservoir210in which a fluidic medium may be contained. The plunger head220is connected to the plunger arm230, such that movement of the plunger arm230in the axial direction of the reservoir210causes movement of the plunger head220in the axial direction of the reservoir210. The plunger head220includes a plunger body portion221and a plunger protruding portion222. In various embodiments, the plunger head220further includes one or more seals225that surround a portion of the plunger body portion221. In various embodiments, the one or more seals225may be made of any suitable material, such as but not limited to, rubber, plastic, composite material, or the like.

The bubble trap portion212of the reservoir210is shaped to have a volume216within an interior of the reservoir210, such that air bubbles in a fluidic medium may be trapped in the volume216when the fluidic medium is expelled from the reservoir210through the port217. In various embodiments, an interior surface of the bubble trap portion212is curved or angled near the port217, so as to define the volume216. In some embodiments, the bubble trap portion212extends from the reservoir body portion211of the reservoir210past a point218of the reservoir210where a fluidic medium from an interior volume of the reservoir body portion211is able to move into an area or channel272of the reservoir210that leads to the port217.

In various embodiments, the reservoir210is shaped such that as the plunger head220is advanced within the reservoir210, a fluidic medium is able to pass through the port217while air bubbles in the reservoir210collect in the volume216defined by a curved or angled surface of the bubble trap portion212of the reservoir210. Such a geometry of the reservoir210allows for decreasing an amount of air bubbles that are delivered with a fluidic medium as compared with traditional reservoir geometries. In some embodiments, the bubble trap portion212of the reservoir210is curved outward from an interior volume defined by the reservoir body portion211, and a fluidic medium is able to pass directly from the interior volume defined by the reservoir body portion211to the port217. In some embodiments, a surface215of the bubble trap portion212of the reservoir210includes a surface finish or material such that air bubbles substantially do not stick to the surface215and are shunted away from the port217toward the volume216. In various embodiments, such a surface finish or material includes a hydrophobic material, a hydrophilic material, or other suitable material.

The plunger body portion221is shaped such that a contour of the plunger body portion221substantially matches or is substantially the same as an inner contour of the reservoir body portion211of the reservoir210. In various embodiments, the plunger body portion221has a diameter that is slightly smaller than a diameter of the inner surface of the reservoir body portion211of the reservoir210, such that the plunger head220is able to slide within the reservoir210. In some embodiments, a seal225on the plunger body portion221is in contact with the inner surface of the reservoir body portion211of the reservoir210when the plunger head220is within the reservoir210.

In various embodiments, the plunger protruding portion222is shaped such that a contour of the plunger protruding portion222substantially matches or is substantially the same as an inner contour of the bubble trap portion212of the reservoir210. In some embodiments, the plunger protruding portion222is curved and protrudes from the plunger body portion221. In various embodiments, the plunger protruding portion222has a size that is slightly smaller than a region defined by the inner surface of the bubble trap portion212of the reservoir210, such that the plunger protruding portion222is able to slide within the volume216of the reservoir210, and such that a space for a dead volume of air is left when the plunger head220is fully advanced within the reservoir210. Thus, in various embodiments, the geometry of the reservoir210and the plunger head220allow for capturing air bubbles in a volume216of the bubble trap portion212when a fluidic medium is being expelled from the port217of the reservoir210.

In various embodiments, the plunger protruding portion222has a size such that when the plunger head220is fully advanced within the reservoir210, the plunger protruding portion222substantially fills the volume216of the bubble trap portion212. Also, in various embodiments, the plunger protruding portion222fills less than all of the volume216of the bubble trap portion212when the plunger head220is fully advanced within the reservoir210, so that one or more air pockets for holding air exist between the plunger protruding portion222and an inner surface of the bubble trap portion212when the plunger head220is fully advanced within the reservoir210. In some embodiments, the plunger protruding portion222extends at least partially into the volume216of the bubble trap portion212when the plunger head220is sufficiently advanced within the reservoir210.

FIG. 9Billustrates a cross-sectional view of the reservoir210in accordance with an embodiment of the present invention.FIG. 9Bis shaded to highlight various features of the reservoir210. The reservoir210includes the reservoir body portion211, the bubble trap portion212, and the port217. The reservoir body portion211has an interior volume270for containing a fluidic medium. The port217is in fluid flow communication with the interior volume270of the reservoir body portion211. The bubble trap portion212has the volume216in fluid flow communication with the interior volume270of the reservoir body portion211for trapping air bubbles that are in the fluidic medium as the fluidic medium is being expelled from the interior volume270.

In various embodiments, the port217is located to a particular side of the interior volume270, and the bubble trap portion212is located to the particular side of the interior volume270. Also, in various embodiments, the bubble trap portion212has a first portion281that extends from the reservoir body portion211away from the interior volume270, and a second portion282that returns back toward the interior volume270. In some embodiments, the reservoir body portion211and the bubble trap portion212are formed together as a single seamless unit. Also, in some embodiments, the first portion281of the bubble trap portion212extends from the reservoir body portion211away from the interior volume270and the second portion282of the bubble trap portion212extends from the first portion281toward the interior volume270.

In various embodiments, the bubble trap portion212includes a curved surface283having a first end region284, a second end region285, and a middle region286between the first end region284and the second end region285. In some embodiments, the first end region284and the second end region285are closer to the interior volume270of the reservoir body portion211than the middle region286is to the interior volume270. Also, in some embodiments, the first end region284is in contact with the reservoir body portion211, and the second end region285is located adjacent to the interior volume270of the reservoir body portion211.

In various embodiments, the curved surface283of the bubble trap portion212is in contact with the fluidic medium when the fluidic medium is in the volume216of the bubble trap portion212. In further embodiments, the curved surface283is approximately U-shaped.FIG. 9Billustrates a cross-sectional view, but in three-dimensions the bubble trap portion212may be shaped, for example, approximately as a semi-toroid. In various embodiments, the reservoir210is shaped such that in order for a fluidic medium to flow from the volume216of the bubble trap portion212to the port217, the fluidic medium must flow through the interior volume270of the reservoir body portion211. In some embodiments, the reservoir210includes the channel272that leads from the interior volume270of the reservoir body portion211to the port217, and the bubble trap portion212encircles at least a portion of the channel272.

FIG. 10Aillustrates a cross-sectional view of a system300in accordance with an embodiment of the present invention. The system300includes a reservoir310, a plunger head320, and a plunger arm330. The reservoir310includes a reservoir body portion311, a bubble trap portion312, and a port317. The reservoir310has an outer surface313and an inner surface314. The inner surface314of the reservoir310defines a hollow interior of the reservoir310, and the hollow interior of the reservoir310is able to contain a fluidic medium. The port317of the reservoir310allows for the fluidic medium to be filled into or expelled from the hollow interior of the reservoir310. The reservoir body portion311of the reservoir310may have any suitable shape, such as but not limited to, a cylinder shape, a tube shape, a barrel shape, a spherical shape, a shape with a rectangular cross-section, or the like.

The plunger head320is located within the reservoir310, and is moveable in an axial direction of the reservoir310, to expand or contract a volume of the reservoir310in which a fluidic medium may be contained. The plunger head320is connected to the plunger arm330, such that movement of the plunger arm330in the axial direction of the reservoir310causes movement of the plunger head320in the axial direction of the reservoir310. The plunger head320includes a plunger body portion321and a plunger protruding portion322. In various embodiments, the plunger head320further includes one or more seals325that surround a portion of the plunger body portion321.

The bubble trap portion312of the reservoir310is shaped so as to form a volume316within an interior of the reservoir310, such that air bubbles in a fluidic medium may be trapped in the volume316of the bubble trap portion312when the fluidic medium is expelled from the reservoir310through the port317. In various embodiments, an interior surface of the bubble trap portion312is angled at a substantially straight angle near the port317, so as to define the volume316. In some embodiments, the bubble trap portion312extends from the reservoir body portion311of the reservoir310past a point318of the reservoir310where a fluidic medium from an interior volume of the reservoir body portion311is able to move into an area or channel372of the reservoir310that leads to the port317.

In various embodiments, the reservoir310is shaped such that as the plunger head320is advanced within the reservoir310, a fluidic medium is able to pass through the port317while air bubbles in the reservoir310collect in the volume316defined by a substantially straight angled surface of the bubble trap portion312of the reservoir310. Such a geometry of the reservoir310may allow for decreasing an amount of air bubbles that are delivered with a fluidic medium as compared with traditional reservoir geometries. In some embodiments, the bubble trap portion312of the reservoir310is angled outward from an interior region of the reservoir310defined by the reservoir body portion311, and a fluidic medium is able to pass directly from the interior region of the reservoir310defined by the reservoir body portion311to the port317. In some embodiments, a surface315of the bubble trap portion312of the reservoir310includes a surface finish or material such that air bubbles substantially do no stick to the surface315and are shunted away from the port317toward the volume316.

The plunger body portion321is shaped such that a contour of the plunger body portion321substantially matches or is substantially the same as a contour of an inner surface of the reservoir body portion311of the reservoir310. In various embodiments, the plunger body portion321has a diameter that is slightly smaller than a diameter of the inner surface of the reservoir body portion311of the reservoir310, such that the plunger head320is able to slide within the reservoir310. In some embodiments, the one or more seals325on the plunger body portion321are in contact with the inner surface of the reservoir body portion311of the reservoir310when the plunger head320is within the reservoir310.

In various embodiments, the plunger protruding portion322is shaped such that a contour of the plunger protruding portion322substantially matches or is substantially the same as an inner contour of the bubble trap portion312of the reservoir310. In some embodiments, the plunger protruding portion322is angled from the plunger body portion321at a substantially straight angle and protrudes from the plunger body portion321. In various embodiments, the plunger protruding portion322has a size that is slightly smaller than a region defined by the inner surface of the bubble trap portion312of the reservoir310, such that the plunger protruding portion322is able to slide within the volume316of the bubble trap portion312, and such that a space for a dead volume of air is left when the plunger head320is fully advanced within the reservoir310. Thus, in various embodiments, the geometry of the reservoir310and the plunger head320allow for capturing air bubbles in a volume316of the bubble trap portion312when a fluidic medium is being expelled from the port317of the reservoir310.

In various embodiments, the plunger protruding portion322has a size such that when the plunger head320is fully advanced within the reservoir310, the plunger protruding portion322substantially fills the volume316of the bubble trap portion312. Also, in various embodiments, the plunger protruding portion322fills less than all of the volume316of the bubble trap portion312when the plunger head320is fully advanced within the reservoir310, so that one or more air pockets for holding air exist between the plunger protruding portion322and an inner surface of the bubble trap portion312when the plunger head320is fully advanced within the reservoir310. In some embodiments, the plunger protruding portion322extends at least partially into the volume316of the bubble trap portion312when the plunger head320is sufficiently advanced within the reservoir310.

FIG. 10Billustrates a cross-sectional view of the reservoir310in accordance with an embodiment of the present invention.FIG. 10Bis shaded to highlight various features of the reservoir310. The reservoir310includes the reservoir body portion311, the bubble trap portion312, and the port317. The reservoir body portion311has an interior volume370for containing a fluidic medium. The port317is in fluid flow communication with the interior volume370of the reservoir body portion311. The bubble trap portion312has the volume316in fluid flow communication with the interior volume370of the reservoir body portion311for trapping air bubbles that are in the fluidic medium as the fluidic medium is being expelled from the interior volume370.

In various embodiments, the port317is located to a particular side of the interior volume370, and the bubble trap portion312is located to the particular side of the interior volume370. Also, in various embodiments, the bubble trap portion312has a first portion381that extends from the reservoir body portion311away from the interior volume370, and a second portion382that returns back toward the interior volume370. In some embodiments, the reservoir body portion311and the bubble trap portion312are formed together as a single seamless unit. Also, in some embodiments, the first portion381of the bubble trap portion312extends from the reservoir body portion311away from the interior volume370and the second portion382of the bubble trap portion312extends from the first portion381toward the interior volume370.

In various embodiments, the reservoir310is shaped such that in order for a fluidic medium to flow from the volume316of the bubble trap portion312to the port317, the fluidic medium must flow through the interior volume370of the reservoir body portion311. In some embodiments, the reservoir310includes the channel372that leads from the interior volume370of the reservoir body portion311to the port317, and the bubble trap portion312encircles at least a portion of the channel372.

In various embodiments, the bubble trap portion312includes a first surface383that defines an edge of the volume316of the bubble trap portion312, and a second surface384that defines another edge of the volume316of the bubble trap portion312, where the second surface384is positioned at an angle with respect to the first surface383. In some embodiments, the angle between the first surface383and the second surface384is less than 90 degrees. Also, in some embodiments, the first surface383is planar with respect to an inner surface of the reservoir body portion311of the reservoir310. In various embodiments, the port317is located to a particular side of the interior volume370and the first portion381of the bubble trap portion312extends from the reservoir body portion311to the particular side.

FIG. 11Aillustrates a cross-sectional view of a system400in accordance with an embodiment of the present invention. The system400includes a reservoir410, a plunger head420, and a plunger arm430. The reservoir410includes a reservoir body portion411, a bubble trap portion412, and a port417. The reservoir410has an outer surface413and an inner surface414. The inner surface414of the reservoir410defines a hollow interior of the reservoir410, and the hollow interior of the reservoir410is able to contain a fluidic medium. The port417of the reservoir410allows for the fluidic medium to be filled into or expelled from the hollow interior of the reservoir410. The reservoir body portion411of the reservoir410may have any suitable shape, such as but not limited to, a cylinder shape, a tube shape, a barrel shape, a spherical shape, a shape with a rectangular cross-section, or the like.

The plunger head420is located within the reservoir410, and is moveable in an axial direction of the reservoir410, to expand or contract a volume of the reservoir410in which a fluidic medium may be contained. The plunger head420is connected to the plunger arm430, such that movement of the plunger arm430in the axial direction of the reservoir410causes movement of the plunger head420in the axial direction of the reservoir410. The plunger head420includes a plunger body portion421and a plunger protruding portion422. In various embodiments, the plunger head420further includes one or more seals425that surround a portion of the plunger body portion421.

The bubble trap portion412of the reservoir410is shaped so as to form a volume416within an interior of the reservoir410, such that air bubbles in a fluidic medium may be trapped in the volume416of the bubble trap portion412when the fluidic medium is expelled from the reservoir410through the port417. In various embodiments, the reservoir410is shaped such that as the plunger head420is advanced within the reservoir410, a fluidic medium is able to pass through the port417while air bubbles in the reservoir410collect in the volume416of the reservoir410. Such a geometry of the reservoir410may allow for decreasing an amount of air bubbles that are delivered with a fluidic medium as compared with traditional reservoir geometries.

The plunger body portion421is shaped such that a contour of an outer surface of the plunger body portion421substantially matches or is substantially the same as a contour of an inner surface of the reservoir body portion411of the reservoir410. In various embodiments, the plunger body portion421has a diameter that is slightly smaller than a diameter of the inner surface of the reservoir body portion411of the reservoir410, such that the plunger head420is able to slide within the reservoir410. In some embodiments, the one or more seals425on the plunger body portion421are in contact with the inner surface of the reservoir body portion411of the reservoir410when the plunger head420is within the reservoir410. In various embodiments, the plunger protruding portion422is shaped such that a contour of an outer surface of the plunger protruding portion422substantially matches or is substantially the same as a contour of an inner surface of the bubble trap portion412of the reservoir410.

FIG. 11Billustrates a cross-sectional view of the reservoir410in accordance with an embodiment of the present invention.FIG. 11Bis shaded to highlight various features of the reservoir410. The reservoir410includes the reservoir body portion411, the bubble trap portion412, and the port417. The reservoir body portion411has an interior volume470for containing a fluidic medium. The port417is in fluid flow communication with the interior volume470of the reservoir body portion411. The bubble trap portion412has the volume416in fluid flow communication with the interior volume470of the reservoir body portion411for trapping air bubbles that are in the fluidic medium as the fluidic medium is being expelled from the interior volume470.

In various embodiments, the port417is located to a particular side of the interior volume470, and the bubble trap portion412is located to the particular side of the interior volume470. Also, in various embodiments, the bubble trap portion412has a first portion481that extends from the reservoir body portion411away from the interior volume470, and a second portion482that returns back toward the interior volume470. In some embodiments, the reservoir body portion411and the bubble trap portion412are formed together as a single seamless unit. Also, in some embodiments, the first portion481of the bubble trap portion412extends from the reservoir body portion411away from the interior volume470and the second portion482of the bubble trap portion412extends from the first portion481toward the interior volume470.

In various embodiments, the bubble trap portion412includes a curved surface483. In some embodiments, the curved surface483of the bubble trap portion412is in contact with the fluidic medium when the fluidic medium is in the volume416of the bubble trap portion412. In various embodiments, the reservoir410is shaped such that in order for a fluidic medium to flow from the volume416of the bubble trap portion412to the port417, the fluidic medium must flow through the interior volume470of the reservoir body portion411. In some embodiments, the reservoir410includes a channel472that leads from the interior volume470of the reservoir body portion411to the port417, and the bubble trap portion412encircles at least a portion of the channel472.

With reference toFIGS. 11A and 11B, in various embodiments, the plunger protruding portion422is shaped such that a contour of the plunger protruding portion422substantially matches or is substantially the same as an inner contour of the bubble trap portion412of the reservoir410. In some embodiments, the plunger protruding portion422is at least partially curved and protrudes from the plunger body portion421. Also, in some embodiments, the plunger protruding porting includes a surface that is substantially parallel to an inner surface of the reservoir body portion411of the reservoir410. In various embodiments, the plunger protruding portion422has a size that is slightly smaller than a region defined by the inner surface of the bubble trap portion412of the reservoir410, such that the plunger protruding portion422is able to slide within the volume416of the reservoir410, and such that a space for a dead volume of air is left when the plunger head420is fully advanced within the reservoir410. Thus, in various embodiments, the geometry of the reservoir410and the plunger head420allow for capturing air bubbles in a volume416of the bubble trap portion412when a fluidic medium is being expelled from the port417of the reservoir410.

In various embodiments, the plunger protruding portion422has a size such that when the plunger head420is fully advanced within the reservoir410, the plunger protruding portion422substantially fills the volume416of the bubble trap portion412. Also, in various embodiments, the plunger protruding portion422fills less than all of the volume416of the bubble trap portion412when the plunger head420is fully advanced within the reservoir410, so that one or more air pockets for holding air exist between the plunger protruding portion422and an inner surface of the bubble trap portion412when the plunger head420is fully advanced within the reservoir410. In some embodiments, the plunger protruding portion422extends at least partially into the volume416of the bubble trap portion412when the plunger head420is sufficiently advanced within the reservoir410.

FIG. 12Aillustrates a cross-sectional view of a system500in accordance with an embodiment of the present invention. The system500includes a reservoir510, a plunger head520, and a plunger arm530. In various embodiments, the system500further includes a needle550. The reservoir510is similar to the reservoir210of the system200(refer toFIG. 9A), and includes a reservoir body portion511and a bubble trap portion512. The bubble trap portion512defines a volume516for trapping air bubbles. Thus, the reservoir510has an air trap geometry that allows for capturing air bubbles.

The plunger head520is similar to the plunger head220of the system200(refer toFIG. 9A). The plunger head520includes a plunger body portion521and a plunger protruding portion522. The plunger head520further includes a depression or relief523for allowing at least a portion of the needle550to be inserted into an interior of the reservoir510when the plunger head520is fully advanced within the reservoir510. In various embodiments, the plunger head520has the relief523for receiving at least a portion of the needle550when the plunger head520is sufficiently advanced within the reservoir510and the portion of the needle550is inserted into the reservoir510. In various embodiments, the reservoir510is shaped to trap air bubbles. Also, in various embodiments, the reservoir510and the plunger head520are shaped so as to minimize a delivery of air bubbles when a fluidic medium is expelled from the reservoir510.

FIG. 12Billustrates a cross-sectional view of the reservoir510in accordance with an embodiment of the present invention.FIG. 12Bis shaded to highlight various features of the reservoir510. The reservoir510includes the reservoir body portion511, the bubble trap portion512, and a port517. The reservoir body portion511has an interior volume570for containing a fluidic medium. The port517is in fluid flow communication with the interior volume570of the reservoir body portion511. The bubble trap portion512has the volume516in fluid flow communication with the interior volume570of the reservoir body portion511for trapping air bubbles that are in the fluidic medium as the fluidic medium is being expelled from the interior volume570.

In various embodiments, the port517is located to a particular side of the interior volume570, and the bubble trap portion512is located to the particular side of the interior volume570. Also, in various embodiments, the bubble trap portion512has a first portion581that extends from the reservoir body portion511away from the interior volume570, and a second portion582that returns back toward the interior volume570. In some embodiments, the reservoir body portion511and the bubble trap portion512are formed together as a single seamless unit. Also, in some embodiments, the first portion581of the bubble trap portion512extends from the reservoir body portion511away from the interior volume570and the second portion582of the bubble trap portion512extends from the first portion581toward the interior volume570.

In various embodiments, the bubble trap portion512includes a curved surface583having a first end region584, a second end region585, and a middle region586between the first end region584and the second end region585. In some embodiments, the first end region584and the second end region585are closer to the interior volume570of the reservoir body portion511than the middle region586is to the interior volume570. Also, in some embodiments, the first end region584is in contact with the reservoir body portion511, and the second end region585is located adjacent to the interior volume570of the reservoir body portion511.

In various embodiments, the curved surface583of the bubble trap portion512is in contact with the fluidic medium when the fluidic medium is in the volume516of the bubble trap portion512. In further embodiments, the curved surface583is approximately U-shaped.FIG. 9Billustrates a cross-sectional view, but in three-dimensions the bubble trap portion512may be shaped, for example, approximately as a semi-toroid. In various embodiments, the reservoir510is shaped such that in order for a fluidic medium to flow from the volume516of the bubble trap portion512to the port517, the fluidic medium must flow through the interior volume570of the reservoir body portion511. In some embodiments, the reservoir510includes a channel572that leads from the interior volume570of the reservoir body portion511to the port517, and the bubble trap portion512encircles at least a portion of the channel572.

FIG. 12Cillustrates a cross-sectional view of the system500ofFIG. 12Ain accordance with another embodiment of the present invention. In the embodiment illustrated inFIG. 12C, the system500further includes a feature560. In various embodiments, the feature560is located between an interior surface515of the bubble trap portion512of the reservoir510and a location of the reservoir510where a fluidic medium is able to be expelled from the reservoir510. The feature560may comprise, for example, a hydrophilic material or a hydrophobic material, that will substantially keep air bubbles from being dispensed through the port517of the reservoir510. As a consequence, a delivery accuracy may be able to be improved since a number of air bubbles expelled from the reservoir510is further limited by the feature560. In various embodiments, the feature560shunts air bubbles in a fluidic medium away from the port517of the reservoir510and toward the volume516of the bubble trap portion512when the fluidic medium is being expelled from an interior volume of the reservoir body portion511of the reservoir510.

FIG. 13Aillustrates a cross-sectional view of a system600in accordance with an embodiment of the present invention. The system600includes a reservoir610, a plunger head620, and a plunger arm630. The reservoir610has a hollow interior that is able to contain a fluidic medium. The reservoir610includes a port617that allows for the fluidic medium to be filled into or expelled from the hollow interior of the reservoir610. In various embodiments, a septum640is located in the port617of the reservoir610, where the septum640is able to be pierced by a needle650. The reservoir610includes a reservoir body portion611that may have any suitable shape, such as but not limited to, a cylinder shape, a tube shape, a barrel shape, a spherical shape, a shape with a rectangular cross-section, or the like.

The plunger head620is located within the reservoir610, and is moveable in an axial direction of the reservoir610, to expand or contract a volume of the reservoir610in which a fluidic medium may be contained. The plunger head620is connected to the plunger arm630, such that movement of the plunger arm630in the axial direction of the reservoir610causes movement of the plunger head620in the axial direction of the reservoir610. The plunger head620is shaped to form a bubble trap region625for trapping air bubbles that are in the fluidic medium as the fluidic medium is expelled from the reservoir610by the plunger head620. In various embodiments, the plunger head620includes a concave portion624that defines the bubble trap region625. In various embodiments, the plunger head620further includes one or more seals626that surround a portion of the plunger head620. In various embodiments, the one or more seals626may be made of any suitable material, such as but not limited to, rubber, plastic, composite material, or the like.

In various embodiments, the plunger head620includes a body portion621, a first protrusion portion622protruding from the body portion621, and a second protrusion portion623protruding from the body portion621. In various embodiments, the bubble trap region625is located between the first protrusion portion622and the second protrusion portion623. It should be appreciated thatFIG. 13Ais a cross-sectional view, and that the plunger head620is actually a three-dimensional object as rotated around a central axis passing in an axial direction of the reservoir610. In various embodiments, the first protrusion portion622surrounds at least a portion of the second protrusion portion623.

FIG. 13Billustrates a cross-sectional view of the plunger head620in accordance with an embodiment of the present invention. With reference toFIGS. 13A and 13B, in various embodiments, the first protrusion portion622extends a first distance682from the body portion621. Also, in various embodiments, the second protrusion portion623extends a second distance683from the body portion621. In some embodiments, the first distance682is greater than the second distance683. Also, in some embodiments, the second distance683is greater than one-fourth of the first distance682. In various embodiments, the second protrusion portion623is dome shaped.

In various embodiments, the concave portion624of the plunger head620includes a curved surface that defines the bubble trap region625. In various embodiments, the curved surface of the concave portion624has a first end position672, a second end position673, and an innermost position671. The first end position672is located on the first protrusion portion622, and the second end position673is located on the second protrusion portion623. The innermost position671is located at an innermost position of the concave portion624with respect to a depth680of the plunger head620. In various embodiments, a depth684of the bubble trap region625defined by the concave portion624is at least greater than one-half of a width685of the bubble trap region625from the first end position672to the second end position673. In various embodiments, the depth684of the bubble trap region625is greater than or equal to one-fourth of the depth680of the plunger head620. In various embodiments, the body portion621of the plunger head620has a depth686and a width681. In various embodiments, the plunger head620includes one or more seal recesses627in which the seals626are located.

A method for expelling a fluidic medium from a reservoir in accordance with an embodiment of the present invention may be performed using the system600. In various embodiments, the plunger head620includes the concave portion624that defines the bubble trap region625. In various embodiments, the method includes expelling the fluidic medium from the reservoir610using the plunger head620, and trapping, in the bubble trap region625defined by the concave portion624of the plunger head620, air bubbles that are in the fluidic medium as the fluidic medium is being expelled from the reservoir610by the plunger head620. In various embodiments, the fluidic medium expelled from the reservoir610is delivered to a body of a patient through the needle650.

FIG. 14Aillustrates a cross-sectional view of a system800in accordance with an embodiment of the present invention. In various embodiments, the system800allows for delivering a fluidic medium, such as to a body of a patient. The system800includes a reservoir810, a plunger head820, and a plunger arm830. The reservoir810includes a reservoir body portion811, a reservoir bubble trap portion812, and a port817. The reservoir810has a hollow interior, and the hollow interior of the reservoir810is able to contain a fluidic medium. The port817of the reservoir810allows for the fluidic medium to be filled into or expelled from the hollow interior of the reservoir810. The reservoir body portion811of the reservoir810may have any suitable shape, such as but not limited to, a cylinder shape, a tube shape, a barrel shape, a spherical shape, a shape with a rectangular cross-section, or the like.

The plunger head820is located within the reservoir810, and is moveable in an axial direction of the reservoir810, to expand or contract a volume of the reservoir810in which a fluidic medium may be contained. The plunger head820is connected to the plunger arm830, such that movement of the plunger arm830in the axial direction of the reservoir810causes movement of the plunger head820in the axial direction of the reservoir810. The plunger head820is shaped to form a bubble trap region825for trapping air bubbles that are in the fluidic medium as the fluidic medium is expelled from the reservoir810by the plunger head820. In various embodiments, the plunger head820includes a concave portion824that defines the bubble trap region825.

In various embodiments, the plunger head820includes a body portion821, a first protrusion portion822protruding from the body portion821, and a second protrusion portion823protruding from the body portion821. In various embodiments, the bubble trap region825is located between the first protrusion portion822and the second protrusion portion823. It should be appreciated thatFIG. 14Ais a cross-sectional view, and that the plunger head820is actually a three-dimensional object as rotated around a central axis passing in an axial direction of the reservoir810. In various embodiments, the first protrusion portion822surrounds at least a portion of the second protrusion portion823.

In various embodiments, the first protrusion portion822extends a first distance from the body portion821. Also, in various embodiments, the second protrusion portion823extends a second distance from the body portion821. In some embodiments, the first distance is greater than the second distance. Also, in some embodiments, the second distance is greater than one-fourth of the first distance. In various embodiments, the second protrusion portion823is dome shaped. In various embodiments, the concave portion824of the plunger head820includes a curved surface that defines the bubble trap region825. In various embodiments, the curved surface of the concave portion824has a first end position, a second end position, and an innermost position. The first end position is located on the first protrusion portion822, and the second end position is located on the second protrusion portion823. The innermost position is located at an innermost position of the concave portion824with respect to a depth of the plunger head820. In various embodiments, a depth of the bubble trap region825defined by the concave portion824is at least greater than one-half of a width of the bubble trap region825from the first end position to the second end position. In various embodiments, the depth of the bubble trap region825is greater than or equal to one-fourth of the depth of the plunger head820.

The reservoir bubble trap portion812of the reservoir810is shaped to have a volume816within an interior of the reservoir810, such that air bubbles in the fluidic medium may be trapped in the volume816when the fluidic medium is expelled from the reservoir810through the port817. In various embodiments, an interior surface815of the reservoir bubble trap portion812is curved or angled near the port817, so as to define the volume816. In some embodiments, reservoir the bubble trap portion812extends from the reservoir body portion811of the reservoir810past a point of the reservoir810where the fluidic medium from an interior volume of the reservoir body portion811is able to move into an area or channel872of the reservoir810that leads to the port817.

In various embodiments, the reservoir810and the plunger head820are shaped such that as the plunger head820is advanced within the reservoir810, the fluidic medium is able to pass through the port817while some air bubbles in the reservoir810collect in the volume816defined by the interior surface815of the reservoir bubble trap portion812of the reservoir810and other air bubbles in the reservoir810collect in the bubble trap region825defined by the concave portion824of the plunger head820. Such a geometry of the reservoir810and the plunger head820allows for decreasing an amount of air bubbles that are delivered with a fluidic medium as compared with traditional reservoir and plunger head geometries. In some embodiments, the reservoir bubble trap portion812of the reservoir810is curved outward from an interior volume870defined by the reservoir body portion811, and a fluidic medium is able to pass directly from the interior volume870defined by the reservoir body portion811to the port817.

In various embodiments, the body portion821of the plunger head820is shaped such that a contour of the body portion821substantially matches or is substantially the same as an inner contour of the reservoir body portion811of the reservoir810. In various embodiments, the body portion821of the plunger head820has a diameter that is slightly smaller than a diameter of an inner surface of the reservoir body portion811of the reservoir810, such that the plunger head820is able to slide within the reservoir810. In some embodiments, a seal826on the body portion821of the plunger head820is in contact with the inner surface of the reservoir body portion811of the reservoir810when the plunger head820is within the reservoir810.

In various embodiments, the reservoir body portion811has the interior volume870for containing the fluidic medium. Also, in various embodiments, the port817is in fluid flow communication with the interior volume870. In various embodiments, the plunger head820is moveable within the reservoir810, and the plunger head820is shaped to form the bubble trap region825for trapping air bubbles that are in the fluidic medium as the fluidic medium is being expelled from the interior volume870through the port817by the plunger head820. Thus, in various embodiments, the geometry of the reservoir810and the plunger head820allow for capturing some air bubbles in the volume816of the reservoir bubble trap portion812and for capturing some air bubbles in the bubble trap region825defined by the plunger head820when the fluidic medium is being expelled through the port817of the reservoir810.

In various embodiments, the reservoir includes the reservoir bubble trap portion812having the volume816in fluid flow communication with the interior volume870for trapping air bubbles that are in the fluidic medium as the fluidic medium is being expelled from the interior volume870. In some embodiments, a contour of the first protrusion portion822of the plunger head820substantially matches an inner contour of the reservoir bubble trap portion812. In various embodiments, the first protrusion portion822of the plunger head820is shaped and positioned such that the first protrusion portion822extends at least partially into the volume816of the reservoir bubble trap portion812when the plunger head820is sufficiently advanced within the reservoir810. In some embodiments, the first protrusion portion822of the plunger head820is shaped and positioned such that when the plunger head820is fully advanced within the reservoir810the first protrusion portion822substantially fills the volume816of the reservoir bubble trap portion812.

In various embodiments, the reservoir810is shaped such that in order for the fluidic medium to flow from the volume816of the reservoir bubble trap portion812to the port817, the fluidic medium must flow through the interior volume870. In some embodiments, the reservoir810further includes the channel872that leads from the interior volume870to the port817. Also, in some embodiments, the reservoir bubble trap portion812includes a first portion that extends from the reservoir body portion811away from the interior volume870, and a second portion that returns back toward the interior volume870, where the reservoir bubble trap portion812encircles at least a portion of the channel872.

With reference toFIGS. 3,5C,6C, and14A, in various embodiments, the system800further includes the drive device80, the disposable housing20, and the durable housing30, where the reservoir810ofFIG. 14Amay correspond to the reservoir40ofFIG. 3. In some embodiments, the drive device80includes the drive device linkage portion82and the motor84for moving the drive device linkage portion82. In some embodiments, the plunger arm830is connected to the plunger head820, and the plunger arm830has a mating portion, which may include threads, teeth, or the like, for mating with the drive device linkage portion82of the drive device80. In various embodiments, the disposable housing20allows for housing the reservoir810and for being secured to a user, such as the user7ofFIG. 1. Also, in various embodiments, the durable housing30allows for housing the motor84of the drive device80, where the durable housing30is configured to be selectively engaged with and disengaged from the disposable housing20.

FIG. 14Billustrates the system800in accordance with an embodiment of the present invention. In the embodiment illustrated inFIG. 14B, the second protrusion portion823of the plunger head820includes a cavity828for receiving a portion of a needle850when the plunger head820is sufficiently advanced within the reservoir810. In various embodiments, the second protrusion portion823is aligned with the port817, such that when the needle850is inserted into the port817, an end852of the needle850is directed toward the second protrusion portion823.

In some embodiments, the reservoir810includes a material860for shunting air bubbles in the fluidic medium away from the port817and toward the volume816of the reservoir bubble trap portion812when the fluidic medium is being expelled from the interior volume870. In various embodiments, the material860is located on at least a portion of the interior surface815of the reservoir bubble trap portion812, such that air bubbles substantially do not stick to the portion of the interior surface815covered with the material860and are shunted away from the port817toward the volume816defined by the reservoir bubble trap portion812. In various embodiments, the material860includes a hydrophobic material, a hydrophilic material, or other suitable material.

The embodiments disclosed herein are to be considered in all respects as illustrative, and not restrictive of the invention. The present invention is in no way limited to the embodiments described above. Various modifications and changes may be made to the embodiments without departing from the spirit and scope of the invention. Various modifications and changes that come within the meaning and range of equivalency of the claims are intended to be within the scope of the invention.