The present disclosure relates generally to ambulatory infusion pumps and, more particularly, to a user-wearable pump, such as a patch pump, for delivering medicament such as insulin to a patient.
There are a wide variety of medical treatments that include the administration of a therapeutic fluid in precise, known amounts at predetermined intervals. Devices and methods exist that are directed to the delivery of such fluids, which may be liquids or gases, are known in the art.
One category of such fluid delivery devices includes insulin injecting pumps developed for administering insulin to patients afflicted with type I, or in some cases, type II diabetes. Some insulin injecting pumps are configured as portable or ambulatory infusion devices can provide continuous subcutaneous insulin injection and/or infusion therapy as an alternative to multiple daily injections of insulin via a syringe or an injector pen. Such ambulatory infusion pumps are worn by the user and may use replaceable cartridges. In some embodiments, these pumps may also deliver medicaments other than, or in addition to, insulin, such as glucagon, pramlintide, and the like. Examples of such pumps and various features associated therewith include those disclosed in U.S. Patent Publication Nos. 2013/0324928 and 2013/0053816 and U.S. Pat. Nos. 8,287,495; 8,573,027; 8,986,253; and 9,381,297, each of which is incorporated herein by reference in its entirety.
One type of pump that has been developed is a patch pump, or micro pump. Patch pumps generally are small pumps, typically ambulatory, that are carried directly on the skin under the user's clothing. Many such pumps are situated directly on the infusion site such that no tubing is required to deliver the insulin and/or other medicament to the patient. Other patch pumps can be positioned on the patient's body with a short length of tubing extending to a nearby infusion site. Some patch pumps can be at least in part disposable, meant to be worn for a period of time such as, e.g., a day or two, and then discarded and replaced by a new patch pump. Other patch pump designs contemplate a disposable component, such as a cartridge that contains medicament, and a reusable or durable component. In such configurations, the disposable and durable components may be joined together by the patient or caregiver in preparation for delivery of the medicament.
Ambulatory infusion pumps such as patch pumps can employ various actuation mechanisms for driving the system to deliver medicament to the user, including electromagnetic drive motors, piezoelectric motors, and electrically driven shape-memory alloy (SMA) wire actuators. SMA wire has been used in a variety of miniaturized mechanism designs, including patch pumps, and has cost and size advantages over other actuation mechanism. SMA wire actuators operate on the principle of material phase transformation due to electrical heating. This phase transformation generates an approximately 4% strain in the form of shrinkage that can be used to operate on a mechanism and extract usable work. One disadvantage of SMA technology is relatively low work and power output that makes it not suitable for applications that require high power or high work output. However, a disposable medical pump with low delivery rates is an example of a type of application for which SMA wire mechanisms would be suitable.
Disclosed herein are apparatuses and methods for an ambulatory infusion pump actuated with a shape memory alloy (SMA) wire. An SMA wire operated mechanism can include an actuator lever to increase the SMA wire's strain into a usable displacement to pull on a pawl that ratchets to a ratchet wheel to rotate a lead screw to advance a plunger a precise amount within a reservoir to deliver a precise amount of fluid.
In an embodiment, an ambulatory infusion pump can include a reservoir configured to contain a medicament, a syringe assembly including a plunger configured to dispense medicament from the reservoir, a ratchet wheel configured to rotate the syringe assembly, a pawl configured to engage with the ratchet wheel and an actuator lever mechanically linked to the pawl. A shape memory wire can be mechanically linked with the actuator lever such that actuation of the shape memory wire shortens the shape memory wire to cause the shape memory wire to move the actuator lever such that the actuator lever moves the pawl to rotate the ratchet wheel and syringe assembly to cause the plunger to dispense a predetermined amount of medicament from the reservoir.
In an embodiment, an ambulatory infusion pump can include a reservoir configured to contain a medicament and a syringe assembly including a plunger configured to dispense medicament from the reservoir. A ratchet wheel configured to rotate the syringe assembly can be disposed on the syringe assembly and a pawl can be engaged with the ratchet wheel. An actuator lever can be mechanically linked to the pawl and a shape memory wire can be mechanically linked to the actuator lever. Actuation of the shape memory wire can shorten the shape memory wire to cause the shape memory wire to move the actuator lever such that the actuator lever moves the pawl to rotate the ratchet wheel and syringe assembly to cause the plunger to dispense a predetermined amount of medicament from the reservoir.
In an embodiment, an ambulatory infusion pump can include a reservoir configured to contain a medicament, a syringe assembly including a plunger configured to dispense medicament from the reservoir and a ratchet wheel and pawl mechanism mechanically linked to the syringe assembly. A shape memory wire can be mechanically linked with the ratchet and pawl mechanism such that actuation of the shape memory wire shortens the shape memory wire to cause the shape memory wire to move the pawl to rotate the ratchet wheel and syringe assembly to cause the plunger to dispense a predetermined amount of medicament from the reservoir.
The above summary is not intended to describe each illustrated embodiment or every implementation of the subject matter hereof. The figures and the detailed description that follow more particularly exemplify various embodiments.
The invention may be more completely understood in consideration of the following detailed description of various embodiments of the invention in connection with the accompanying drawings, in which:
While the invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the invention to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.
The following detailed description should be read with reference to the drawings in which similar elements in different drawings are numbered the same. The drawings, which are not necessarily to scale, depict illustrative embodiments and are not intended to limit the scope of the disclosure.
A shape memory alloy (SMA) wire 108, such as Nitinol, can extend from electrical connectors 110 and be routed around a pin 112. In embodiments, SMA wire 108 can be configured as a single continuous wire. Pin 112 can be mounted on assembly 108 in a manner that allows limited lateral movement of pin 112 and pin 112 can extend through an aperture in an actuator lever 114 with the pin 112 having a head that is larger than the aperture to prevent the actuator lever 114 from disengaging from pin 112. Actuator lever 114 can further include a first projection 116 for holding a spring 120 and a second projection 118 that extends through an aperture in a pawl 122. First projection 116 can be mounted on a rotation pin 124 that is rotatably fixed on the board 106 to enable the actuator lever 114 to be rotated about pin 124. Pawl 122 includes an elongate aperture 126 sized to fit around a portion of a ratchet wheel 128 and a distal surface 130 on which an individual tooth of the ratchet wheel can rest. As will be described in more detail below, rotation of ratchet wheel 128 drives a lead screw 132 to move a plunger 134 to deliver medicament contained in the reservoir 102 out an outlet 136.
Referring now to
In embodiments, spring 120 is a torsion spring having an arm 121 that wraps around second projection 118 connecting the actuator lever 114 to the pawl 122. As such, following actuation of the SMA wire, when the wire returns to its original, longer length the biasing force of the arm 121 of the torsion spring 120 on the second projection 118 rotates the actuator lever 114 back about mounting pin 124 to return the pin 112 and second projection 118 to their original positions depicted in
The manner in which rotation of the ratchet wheel 128 effects delivery of medicament with pump 100 can be described in greater detail with reference to
Referring now to
In this embodiment, the SMA wire 408 is configured as a spring. The bias spring 420 extends from the same mounting pin 424 that connects the pawl 422 and the actuator lever 414 to another mounting pin 440 such that the bias spring 420 is aligned across from the SMA wire 408 along the actuator lever 414. As the actuator lever 414 pivots about the rotation pin 424, a pair of stop pins 442 are positioned on opposing sides of the actuator lever 414 adjacent the end to which the SMA wire 408 is attached to limit a path of travel of the actuator lever 414. This corresponds to how limiting how far the pawl 422 (“hot” state) and ratchet wheel 428 (“cold”) state can travel, as will be apparent from the below.
In contrast to the previous embodiment, there is no bias spring 420 connected to the pawl 522 and actuator lever 514 in addition to the SMA wire spring 508. In addition, the positioning of the electrical connector pin 510 and the movable pin 512 connected to the actuator lever 514 is flipped, with the electrical connector pin 510 being located closer to the ratchet wheel 528. In this embodiment, the actuator lever 514 angles to extend from the pin 512 to the mounting pin 518 for the pawl 522. A mechanical advantage of this configuration of 1:2 is applied to the actuator lever 514, which reduces the force required to actuate the lever 514 and, consequently, the ratchet wheel 528. As with the previous embodiment, as the actuator lever 514 pivots about the rotation pin 524, a pair of stop pins 542 are positioned on opposing sides of the actuator lever 514 to limit a path of travel of the actuator lever 514. This corresponds to limiting how far the pawl 522 and ratchet wheel 528 can travel, as will be apparent from the below.
Referring to
The transition between hot (
Referring to
In embodiments, an ambulatory infusion pump can include a reservoir configured to contain a medicament, a syringe assembly including a plunger configured to dispense medicament from the reservoir, a ratchet wheel configured to rotate the syringe assembly, a pawl configured to engage with the ratchet wheel and an actuator lever mechanically linked to the pawl. A shape memory wire can be mechanically linked with the actuator lever such that actuation of the shape memory wire shortens the shape memory wire to cause the shape memory wire to move the actuator lever such that the actuator lever moves the pawl to rotate the ratchet wheel and syringe assembly to cause the plunger to dispense a predetermined amount of medicament from the reservoir.
In embodiments, the pump further includes means for limiting an amount that the actuator lever can move.
In embodiments, the means for limiting the amount that the actuator lever can move comprises a pair of pins.
In embodiments, the amount that the actuator lever can move corresponds to how much the ratchet wheel is rotated.
In embodiments, the pair of pins are located on opposing sides of an end of the actuator lever.
In embodiments, the pump further includes a pin about which the actuator lever rotates.
In embodiments, the pump further includes a mounting pin connecting the actuator level to the pawl.
In embodiments, the actuator lever moves the pawl by pulling on the pawl away from the ratchet wheel with the mounting pin.
In embodiments, the ratchet wheel includes a plurality of teeth and the shape memory wire returns to an elongated state following actuation, and the pawl advances a single tooth along the ratchet wheel when the shape memory wire returns to the elongated state
In embodiments, the shape memory wire is configured as a spring.
In embodiments, an ambulatory infusion pump can include a reservoir configured to contain a medicament, a syringe assembly including a plunger configured to dispense medicament from the reservoir and a ratchet wheel and pawl mechanism mechanically linked to the syringe assembly. A shape memory wire can be mechanically linked with the ratchet and pawl mechanism, such that actuation of the shape memory wire shortens the shape memory wire to cause the shape memory wire to move the pawl to rotate the ratchet wheel and syringe assembly to cause the plunger to dispense a predetermined amount of medicament from the reservoir.
In embodiments the pump further includes means for limiting an amount that the pawl can move.
In embodiments, the means for limiting the amount that the pawl can move comprises a pair of pins.
In embodiments, the pair of pins are located on opposing sides of an end of an actuator lever mechanically linked to the pawl.
In embodiments, the pump further includes an actuator lever mechanically linked to the pawl
In embodiments, the pump further includes a pin about which the actuator lever rotates.
In embodiments, the pump further includes a mounting pin connecting the actuator level to the pawl.
In embodiments, the actuator lever moves the pawl by pulling on the pawl away from the ratchet wheel with the mounting pin.
In embodiments, the ratchet wheel includes a plurality of teeth and the shape memory wire returns to an elongated state following actuation, and the pawl advances a single tooth along the ratchet wheel when the shape memory wire returns to the elongated state
In embodiments, the shape memory wire is configured as a spring.
In embodiments, an ambulatory infusion pump can include a reservoir configured to contain a medicament and a syringe assembly including a plunger configured to dispense medicament from the reservoir. A ratchet wheel configured to rotate the syringe assembly can be disposed on the syringe assembly and a pawl can be engaged with the ratchet wheel. An actuator lever can be mechanically linked to the pawl and a shape memory wire can be mechanically linked to the actuator lever. Actuation of the shape memory wire can shorten the shape memory wire to cause the shape memory wire to move the actuator lever such that the actuator lever moves the pawl to rotate the ratchet wheel and syringe assembly to cause the plunger to dispense a predetermined amount of medicament from the reservoir.
In some embodiments, the actuator lever pulls on the pawl to rotate the ratchet wheel and syringe assembly when the shape memory wire is actuated.
In some embodiments, the actuator lever pushes on the pawl to rotate the ratchet wheel and syringe assembly when the shape memory wire is actuated.
In some embodiments, the ratchet wheel comprises a plurality of teeth and a distance between each tooth corresponds to the predetermined amount of medicament.
In some embodiments, each actuation of the shape memory wire causes the pawl to move a single tooth along the ratchet wheel.
In some embodiments, the pawl includes an elongate aperture configured to fit around a portion of the plurality of teeth of the ratchet wheel.
In some embodiments, a spring is mechanically linked to the actuator lever and wherein the spring is configured to aid in returning the actuator lever to an original position following actuation of the shape memory wire.
In some embodiments, the syringe assembly comprises a drive tube having internal threads interfaced with a lead screw attached to the plunger and the ratchet wheel is disposed around the drive tube such that rotation of the ratchet causes rotation of the drive tube and lead screw to advance the plunger.
In some embodiments, the actuator lever pivots about a pin.
In some embodiments, an adhesive patch is configured to retain the ambulatory infusion pump on a user's body.
In embodiments, an ambulatory infusion pump can include a reservoir configured to contain a medicament, a syringe assembly including a plunger configured to dispense medicament from the reservoir and a ratchet wheel and pawl mechanism mechanically linked to the syringe assembly. A shape memory wire can be mechanically linked with the ratchet and pawl mechanism such that actuation of the shape memory wire shortens the shape memory wire to cause the shape memory wire to move the pawl to rotate the ratchet wheel and syringe assembly to cause the plunger to dispense a predetermined amount of medicament from the reservoir.
In some embodiments, the pawl pulls on the ratchet wheel when the shape memory wire is actuated.
In some embodiments, the pawl pushes the ratchet wheel when the shape memory wire is actuated.
In some embodiments, the ratchet wheel comprises a plurality of teeth and wherein a distance between each tooth corresponds to the predetermined amount of medicament.
In some embodiments, each actuation of the shape memory wire causes the pawl to move a single tooth along the ratchet wheel.
In some embodiments, the pawl includes an elongate aperture configured to fit around a portion of the plurality of teeth of the ratchet wheel.
In some embodiments, an actuator lever is configured to cause a corresponding movement of the pawl when moved by the shape memory wire, and a spring mechanically is linked to the actuator lever to aid in returning the actuator lever to an original position following actuation of the shape memory wire.
In some embodiments, the actuator lever pivots about a pin.
In some embodiments, the syringe assembly comprises a drive tube having internal threads interfaced with a lead screw attached to the plunger and the ratchet wheel is disposed around the drive tube such that rotation of the ratchet causes rotation of the drive tube and lead screw to advance the plunger.
In some embodiments, an adhesive patch is configured to retain the ambulatory infusion pump on a user's body.
Embodiments of the present disclosure include components capable of and methods using wired and wireless transmission and receipt of signals for exchange of information and commands between and among any of the components as described herein, including, e.g., between a pump and a smartphone; among a pump, a CGM and a smartphone; between a dedicated remote controller and a pump; among a dedicated remote controller, a CGM and a pump; among a dedicated remote controller, a BGM and a pump, and other combinations as would be contemplated by those of skill in the art.
Although embodiments described herein may be discussed in the context of the controlled delivery of insulin, delivery of other medicaments, singly or in combination with one another or with insulin, including, for example, glucagon, pramlintide, etc., as well as other applications are also contemplated. Device and method embodiments discussed herein may be used for pain medication, chemotherapy, iron chelation, immunoglobulin treatment, dextrose or saline IV delivery, treatment of various conditions including, e.g., pulmonary hypertension, or any other suitable indication or application. Non-medical applications are also contemplated.
With regard to the above detailed description, like reference numerals used therein may refer to like elements that may have the same or similar dimensions, materials, and configurations. While particular forms of embodiments have been illustrated and described, it will be apparent that various modifications can be made without departing from the spirit and scope of the embodiments herein. Accordingly, it is not intended that the invention be limited by the forgoing
The entirety of each patent, patent application, publication, and document referenced herein is hereby incorporated by reference. Citation of the above patents, patent applications, publications and documents is not an admission that any of the foregoing is pertinent prior art, nor does it constitute any admission as to the contents or date of these documents.
Modifications may be made to the foregoing embodiments without departing from the basic aspects of the technology. Although the technology may have been described in substantial detail with reference to one or more specific embodiments, changes may be made to the embodiments specifically disclosed in this application, yet these modifications and improvements are within the scope and spirit of the technology. The technology illustratively described herein may suitably be practiced in the absence of any element(s) not specifically disclosed herein. The terms and expressions which have been employed are used as terms of description and not of limitation and use of such terms and expressions do not exclude any equivalents of the features shown and described or portions thereof and various modifications are possible within the scope of the technology claimed. Although the present technology has been specifically disclosed by representative embodiments and optional features, modification and variation of the concepts herein disclosed may be made, and such modifications and variations may be considered within the scope of this technology.
This application claims benefit to the provisional application U.S. Application No. 63/470,364, filed on Jun. 1, 2023.
Number | Date | Country | |
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63470364 | Jun 2023 | US |