Patent ID: 8313081

Claim:
A parallel-acting roller clamp for regulating fluid flow through a deformable plastic tube, comprising: an elongated body including left and right side walls and a bottom wall, such walls defining an elongated chamber; wherein the bottom wall defines a clamping surface having a length and a relief groove extending along a substantial portion of the clamping surface's length, such relief groove having a transverse width that defines a taper, and a pair of edges that converge monotonically from a maximum separation at a first end to a single point at a second, opposite end; and a roller wheel located at least partially within the elongated chamber and configured to roll along an axis substantially parallel with the clamping surface of the bottom wall, while directly contacting the plastic tube and pinching the plastic tube between the roller wheel and the clamping surface; wherein the portion of the relief groove located beneath the roller wheel accommodates a portion of the plastic tube located therebetween, with the transverse width of such relief groove portion determining the size of a lumen formed in the plastic tube and thereby regulating fluid flow through the tube; wherein the taper of the relief groove's transverse width defines a convergence angle that is greater in a high-flow region, adjacent the first end of the relief groove, than it is in a low-flow region, adjacent the second end of the relief groove; and wherein the transverse width of the relief groove narrows proximate the second end of the relief groove to create a shutoff position spaced from the second end.