US 11,998,718 B2
System and method for syringe plunger engagement with an injector
Kevin Cowan, Allison Park, PA (US); James Dedig, Pittsburgh, PA (US); Shahab Taheri, Kleinmachnow (DE); Abhinav Srivastava, Pittsburgh, PA (US); Barry Tucker, Verona, PA (US); Michael Swantner, Saxonburg, PA (US); Christopher Capone, Pittsburgh, PA (US); Jaroslow Wlodarczyk, Lower Burrell, PA (US); and Andrew Osan, Pittsburgh, PA (US)
Assigned to BAYER HEALTHCARE LLC, Whippany, NJ (US)
Appl. No. 17/999,592
Filed by BAYER HEALTHCARE LLC, Whippany, NJ (US)
PCT Filed Jun. 16, 2021, PCT No. PCT/US2021/037574
§ 371(c)(1), (2) Date Nov. 22, 2022,
PCT Pub. No. WO2021/257667, PCT Pub. Date Dec. 23, 2021.
Claims priority of provisional application 62/705,265, filed on Jun. 18, 2020.
Prior Publication US 2023/0285666 A1, Sep. 14, 2023
Int. Cl. A61M 5/145 (2006.01); A61M 5/315 (2006.01); A61M 5/36 (2006.01)
CPC A61M 5/14546 (2013.01) [A61M 5/31515 (2013.01); A61M 5/365 (2013.01); A61M 2005/14553 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A plunger for use with a syringe, the plunger comprising:
a plunger body defining a central longitudinal axis and having a proximal end, a distal end, and a circumferential sidewall connecting the proximal end and the distal end; and
at least one retaining member associated with and extending proximally from the plunger body, the at least one retaining member comprising:
a first end connected to the plunger body;
a second end proximal to the first end and radially and resiliently deflectable relative to the first end; and
at least one catch on the second end,
wherein the at least one retaining member has an outer surface configured to engage a plunger engagement sleeve of a plunger engagement mechanism on a piston of a fluid injector system when the plunger is in a locked state with the piston,
wherein the at least one retaining member has an inner surface configured to engage a plunger engagement post of the plunger engagement mechanism when the plunger is in the locked state with the piston,
wherein the at least one catch is configured to fixedly engage a locking feature on one of the plunger engagement sleeve and the plunger engagement post when the plunger is in the locked state with the piston to prevent axial movement of the plunger relative to the piston,
wherein the at least one catch has a first rounded or angled proximal surface at a proximal end of the at least one catch for flexibly engaging a distal end of the locking feature on one of the plunger engagement sleeve and the plunger engagement post during engagement of the plunger to the piston, and a second rounded or angled distal surface at a distal end of the at least one catch for flexibly engaging a proximal end of the locking feature on one of the plunger engagement sleeve and the plunger engagement post during disengagement of the plunger from the piston; and
wherein in an unlocked state of the plunger engagement mechanism the first rounded proximal surface and the second rounded distal surface of the at least one catch are configured to radially deflect the second end of the at least one retaining member upon axial movement of the piston relative to the plunger due to a flexing interaction of the at least one catch with the locking feature on one of the plunger engagement sleeve and the plunger engagement post.