Search

EP-3777923-B1 - PUMPING FLUID DELIVERY SYSTEMS AND METHODS USING FORCE APPLICATION ASSEMBLY

EP3777923B1EP 3777923 B1EP3777923 B1EP 3777923B1EP-3777923-B1

Inventors

  • KAMEN, DEAN
  • GRAY, Larry, B
  • YEATON, ERIC

Dates

Publication Date
20260513
Application Date
20070209

Claims (7)

  1. A valve (4000) for unidirectional flow in a pumping mechanism for dispensing a therapeutic fluid, the valve comprising: a first portion (2610) having an inlet (4030) and an outlet (4040), wherein the inlet (4030) is fluidly connected to the outlet (4040) via an inlet chamber (4050); a second portion (2620) having a force application member (4100); and a membrane (4060) separating the first and second portions (2610, 2620), characterized in that : the outlet (4040) has a circumferentially disposed valve seat (4070) and the force application member (4100) is configured to apply a biasing force to sealingly hold the membrane (4060) against the valve seat (4070) so as to restrict flow to the outlet (4040) or from the outlet (4040), unless fluid pressure in either the inlet or the outlet is sufficient to overcome the biasing force, thereby unseating the membrane (4060) from the valve seat (4070) and establishing flow through the valve, wherein the inlet (4030), the inlet chamber (4050), the outlet (4040) and the membrane (4060) are configured such that when the membrane (4060) is sealingly held to the valve seat (4070), fluid upstream of the outlet (4040) contacts a larger area of the membrane (4060) than does fluid downstream of the outlet, thereby giving greater mechanical advantage to the upstream fluid and causing the valve (4000) to open in response to a lower pressure at the inlet (4030) and to a higher pressure in the outlet (4040), and encouraging unidirectional flow from the inlet (4030) and to the outlet (4040).
  2. A valve (4000) according to claim 1, wherein the first portion is a disposable portion (2610) and the second portion is a reusable portion (2620).
  3. A valve (4000) according to claim 1 or claim 2, wherein the force application member (4100) further includes a spring (4010) and a poppet (4020).
  4. A valve (4000) according to claim 3, further comprising a mechanism (4090) for adjusting the spring force.
  5. A valve (4000) according to any preceding claim further comprising a poppet (4020) biased against valve seat by a poppet biasing spring (4010).
  6. A valve (4000) according to any preceding claim, wherein the first portion (2610) and the second portion (2620) are components of a fluid delivery device sized to be worn as a patch.
  7. The valve (4000) of any preceding claim wherein the membrane (4060) is continuous.

Description

Field of the Invention This application relates generally to pumping fluid delivery systems and methods using force application assembly. Background Many potentially valuable medicines or compounds, including biologicals, are not orally active due to poor absorption, hepatic metabolism or other pharmacokinetic factors. Additionally, some therapeutic compounds, although they can be orally absorbed, are sometimes required to be administered so often it is difficult for a patient to maintain the desired schedule. In these cases, parenteral delivery is often employed or could be employed. Effective parenteral routes of drug delivery, as well as other fluids and compounds, such as subcutaneous injection, intramuscular injection, and intravenous (IV) administration include puncture of the skin with a needle or stylet. Insulin is an example of a therapeutic fluid that is self-injected by millions of diabetic patients. Users of parenterally delivered drugs would benefit from a wearable device that would automatically deliver needed drugs/compounds over a period of time. To this end, there have been efforts to design portable devices for the controlled release of therapeutics. Such devices are known to have a reservoir such as a cartridge, syringe, or bag, and to be electronically controlled. These devices suffer from a number of drawbacks including the malfunction rate. Reducing the size, weight and cost of these devices is also an ongoing challenge. US 320030073952 describes a valve for a pump. Summary of the Invention In one embodiment, there is provided a valve according to claim 1. A method of dispensing a therapeutic fluid from a line is described. The method includes providing an inlet line connectable to an upstream fluid source. The inlet line is in downstream fluid communication with a pumping chamber. The pumping chamber has a pump outlet. The method also includes actuating a force application assembly so as to restrict retrograde flow of fluid through the inlet while pressurizing the pumping chamber to urge flow through the pump outlet.In a related example, actuating the force application assembly includes using travel of the force application assembly during a work stroke to restrict retrograde flow and to pressurize the pumping chamber in a single mechanical action. In a further related example, a given degree of travel of the force actuation assembly restricts retrograde flow, and a greater degree of travel pressurizes the pumping chamber. In a further related example, actuating the force application assembly includes restricting retrograde flow toward the fluid source by occluding the inlet line. Alternatively or in addition, the method also includes preventing reverse flow of fluid from a dispensing chamber into the pumping chamber by using a passive valve placed therebetween. Optionally actuating the force application assembly includes using a shape-memory actuator. Also optionally, using the shape-memory actuator includes inducing a phase change in a shape memory wire to transmit a force around a pulley to the force application assembly. In a further example, the method further includes measuring a parameter related to flow through the line; and adjusting operation of the pump based on the measured parameter. Optionally measuring the parameter related to flow through the line includes determining a change in volume of a resilient chamber disposed downstream of the pumping chamber. Optionally, measuring the parameter includes using acoustic volume measurement. In a further example, a tortuous flow-impedance located downstream of the resilient chamber supplies a fluid impedance sufficient to cause the resilient chamber to expand in response to pumping. Alternatively or in addition, the method further includes causing fluid to flow downstream from the pump outlet through a tortuous flow-impeding conduit. The conduit may have various forms. It may have at least two turns. It may be coiled. It may have a serpentine shape. Optionally, the conduit has a length and an internal diameter selected to provide a predetermined impedance based on at least one of a viscosity and a density of the fluid. Optionally the internal diameter of the conduit is sufficiently large so as to prevent occlusion due to flow of the fluid through the conduit. In a further example, the inlet line, the pumping chamber, the pump outlet and the force application assembly are enclosed inside a patch-sized housing, and actuating the force application assembly includes using a processor inside the housing to cause actuation of the force application assembly. Optionally, the housing has a largest dimension, and the conduit has a length greater than the largest dimension. In a further example, actuating the force application assembly includes inducing using a shape memory actuator. Optionally, using a shape memory actuator includes using one of a plurality of electrical paths of different lengths through the shape-memory actuator, and eac