Patent ID: 8857503

Claim:
A heat exchanger comprising: a plurality of stacked tubular members defining flow passages therethrough, the tubular members each having raised peripheral end portions defining respective inlet and outlet openings, so that in the stacked tubular members, the respective inlet and outlet openings communicate to define inlet and outlet manifolds; and a bypass conduit attached to the stacked tubular members and having opposite end portions and a tubular intermediate wall extending therebetween defining a flow channel having a longitudinal axis, the opposite end portions of the bypass conduit defining respectively a first fluid opening and a second fluid opening respectively communicating with the inlet manifold and the outlet manifold, the first fluid opening and the second fluid opening each having an axis generally perpendicular to the longitudinal axis of the flow channel defined by said tubular intermediate wall, the flow channel having a first flow passage in direct communication with the fluid inlet and a second flow passage in direct communication with the fluid outlet, wherein the first flow passage and second flow passage communicate with each other through a flow restricting calibrated bypass flow passage for a continuous flow of fluid bypassing the stacked tubular members, the flow restricting calibrated bypass flow passage being defined by a portion of the tubular intermediate wall that tapers inwardly width-wise and height-wise from the respective first and second flow passages forming a region of reduced cross-sectional area extending between and interconnecting said first and second flow passages, the flow restricting calibrated bypass flow passage having a length less than the length of either said first flow passage and said second flow passage, where the reduced cross-sectional area is defined by cross-sectional areas that are less than a cross sectional area of the first and second respective flow passages of the bypass conduit flow channel such that the flow restricting calibrated bypass flow passage has a flow resistance substantially greater than the flow resistance of the first flow passage and the second flow passage of the bypass conduit.