US 12,419,618 B2
Biopsy device having a hydraulic drive assembly
Chad Van Liere, Phoenix, AZ (US)
Assigned to C. R. Bard, Inc., Franklin Lake, NJ (US)
Filed by C.R. Bard, Inc., Franklin Lakes, NJ (US)
Filed on Jul. 16, 2021, as Appl. No. 17/377,503.
Application 17/377,503 is a continuation of application No. 16/344,211, granted, now 11,096,676, previously published as PCT/US2017/056918, filed on Oct. 17, 2017.
Claims priority of provisional application 62/424,913, filed on Nov. 21, 2016.
Prior Publication US 2021/0338213 A1, Nov. 4, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. A61B 10/02 (2006.01); A61B 17/00 (2006.01)
CPC A61B 10/0233 (2013.01) [A61B 2010/0208 (2013.01); A61B 2017/00539 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A biopsy device, comprising:
a hydraulic drive assembly that includes:
a chamber housing configured to define a proximal chamber, a distal chamber, and a transition chamber, the transition chamber interposed between the proximal chamber and the distal chamber, wherein the proximal chamber, the transition chamber, and the distal chamber collectively form a continuous passage in the chamber housing, the proximal chamber having a first transverse area and the distal chamber having a second transverse area, the first transverse area being larger than the second transverse area;
a drive piston having a first proximal end portion and a first distal end portion, the first distal end portion having a piston head, the first proximal end portion having a piston tail, the piston tail linearly spaced from the piston head, the drive piston located in the proximal chamber and configured to move in the proximal chamber;
a driven piston having a second proximal end portion and a second distal end portion, the driven piston located in the distal chamber and configured to move in the distal chamber, the second proximal end portion being opposed to the piston head of the drive piston;
a cavity defined in the chamber housing between the drive piston and the driven piston; and
a hydraulic fluid of a fixed quantity that fills the cavity between the drive piston and the driven piston to establish a hydraulic connection between the drive piston and the driven piston;
a drive mechanism drivably connected to the drive piston, the drive mechanism configured to move the drive piston in the proximal chamber, the drive mechanism includes:
a motor having a rotatable shaft,
a drive gear attached to the rotatable shaft,
a driven gear engaged with the drive gear, the driven gear configured to rotate about a first rotational axis, and
a drive link member configured to couple the driven gear to the first proximal end portion of the drive piston, the drive link member having a first end portion and a second end portion spaced apart from the first end portion, the first end portion of the drive link member rotatably coupled to the driven gear at a second rotational axis radially offset by an offset distance from the first rotational axis, and the second end portion of the drive link member rotatably coupled to the first proximal end portion of the drive piston at a pivot axis at the first proximal end portion of the drive piston; and
an elongate biopsy member connected to the second distal end portion of the driven piston.