Sensing system for detecting a piston in a medical fluid container
First Claim
1. A medication delivery device comprising:
- a housing including a container retainer;
a medication container held within the container retainer, the medication container including a barrel and a plunger, the barrel made of a light transmitting material and extending in an axial direction between a forward outlet end and a rearward end, the plunger having at least one peripheral surface region in fluid tight engagement with an interior surface of a wall of the barrel to seal medication in the barrel forward of the plunger;
an advancing mechanism within said housing operable to advance said plunger within said barrel to dispense medication from the medication container through said forward outlet end;
a light source mounted within said housing proximate the rearward end of said barrel and configured to emit light directly into a thickness of the barrel wall, the barrel wall configured to serve as a waveguide to guide the light to travel therein in the axial direction, and wherein said light source is a single light emitting diode;
a light detector mounted within the container retainer and arranged to extend along a length of the barrel to detect reflected light that was emitted by the light source, traveled through the barrel wall serving as the waveguide,a controller mounted within the housing in communication with said light detector to determine an axial position of the at least one peripheral surface region within the medication container based on data from said light detector of said detected reflected light.
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Accused Products
Abstract
A sensing system for determining a position of a plunger within a fluid container. The sensing system includes a light source, a light detector and a controller. The light source is configured to emit light into a barrel wall of the fluid container so that the barrel wall serves as a waveguide to guide the light to travel therein in an axial direction. The light detector is positioned to detect reflected light that was emitted by the light source, traveled through the barrel wall serving as the waveguide, and then reflected off a surface of the plunger. The controller is in communication with the light detector to determine an axial position of the plunger surface based on data from the light detector of the detected reflected light.
35 Citations
26 Claims
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1. A medication delivery device comprising:
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a housing including a container retainer; a medication container held within the container retainer, the medication container including a barrel and a plunger, the barrel made of a light transmitting material and extending in an axial direction between a forward outlet end and a rearward end, the plunger having at least one peripheral surface region in fluid tight engagement with an interior surface of a wall of the barrel to seal medication in the barrel forward of the plunger; an advancing mechanism within said housing operable to advance said plunger within said barrel to dispense medication from the medication container through said forward outlet end; a light source mounted within said housing proximate the rearward end of said barrel and configured to emit light directly into a thickness of the barrel wall, the barrel wall configured to serve as a waveguide to guide the light to travel therein in the axial direction, and wherein said light source is a single light emitting diode; a light detector mounted within the container retainer and arranged to extend along a length of the barrel to detect reflected light that was emitted by the light source, traveled through the barrel wall serving as the waveguide, a controller mounted within the housing in communication with said light detector to determine an axial position of the at least one peripheral surface region within the medication container based on data from said light detector of said detected reflected light. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
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19. A medication delivery device comprising:
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a housing including a container retainer; a medication container disposed within the container retainer, the medication container including a barrel and a plunger, the barrel comprising a light transmitting material and extending in an axial direction between a forward outlet end and a rearward end, the plunger having at least one peripheral surface region in fluid tight engagement with an interior surface of a wall of the barrel to seal medication in the barrel forward of the plunger; an advancing mechanism disposed within said housing and operable to advance said plunger within said barrel to dispense medication from the medication container through said forward outlet end; a light source disposed within said housing and configured to emit light directly into the barrel wall, the barrel wall configured to serve as a waveguide to guide the light to travel therein in the axial direction; a light detector disposed within the container retainer and configured to detect light that was emitted by the light source and reflected off the at least one peripheral surface region after the light traveled axially through the barrel wall; a first light polarizing filter and a second light polarizing filter, said first and second light polarizing filters oriented transverse to each other, said first light polarizing filter disposed between said light detector and said container, said second light polarizing filter arranged on said container retainer over said container to restrict ambient light; and a controller disposed within the housing in communication with said light detector, the controller configured to determine an axial position of the at least one peripheral surface region within the medication container based on data from said light detector of said detected reflected light. - View Dependent Claims (20, 21, 22)
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23. A medication delivery device comprising:
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a housing including a container retainer; a medication container held within the container retainer, the medication container including a barrel and a plunger, the barrel made of a light transmitting material and extending in an axial direction between a forward outlet end and a rearward end, the plunger having at least one peripheral surface region in fluid tight engagement with an interior surface of a wall of the barrel to seal medication in the barrel forward of the plunger; an advancing mechanism within said housing operable to advance said plunger within said barrel to dispense medication from the medication container through said forward outlet end; a light source disposed within said housing proximate the rearward end of said barrel and configured to emit light centered on a middle of a radial thickness of the barrel wall, the barrel wall configured to serve as a waveguide to guide the light to travel therein in the axial direction; a light detector disposed within the container retainer and arranged to extend along a length of the barrel, the light detector configured to detect light that was emitted by the light source and reflected off the at least one peripheral surface region after the light traveled axially through the barrel wall; and a controller disposed within the housing in communication with said light detector, said controller configured to determine an axial position of the at least one peripheral surface region within the medication container based on data from said light detector of said detected reflected light. - View Dependent Claims (24, 25, 26)
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Specification