Abstract: Monitoring concentration of components of blood flowing through a flowpath including flowing the components through a transparent channel, directing light to the channel along an axis intersecting the channel, detecting light passing through the channel along the axis, detecting light scattered off of the axis, and determining concentration of components based on the light passing along the axis and/or the light scattered off of the axis. Also disclosed is a movable cover to block ambient light from a photodetector after mounting of a removable transparent flow channel.

Abstract: A fluid flow chamber cassette that can be mounted with either its front wall or rear wall against a supporting machine and has a flexible tube that extends from a sidewall and forms a loop that is symetrical about a loop axis that is transverse to the side wall so that the loop will be acted upon by a pump roller on the machine both when the front wall is against the machine and when the rear wall is against the machine. Also disclosed is automatically fixing the initial liquid levels and amounts of air in venous and arterial chambers of fluid flow transfer device apparatus by having the arterial chamber inlet enter the arterial chamber at a position higher than the arterial chamber outlet, having the venous chamber inlet enter the venous chamber at a position higher than the venous chamber outlet, and priming the apparatus by causing reverse flow, so that the liquid rises in the venous and arterial chambers to the level of the entrances of the inlets.

Abstract: A pump control apparatus including a variable speed pump controllable in response to a pump drive signal, a signal generator generating a commanded flowrate signal indicating desired flowrate of the pump, a flowrate sensor providing a sensed flowrate signal indicating sensed flowrate of the pump, and an integrator connected to the sensor and generator to receive and integrate the commanded flowrate signal and the sensed flowrate signal and to provide the pump drive signal based on the difference in integrated values of the signals so as to achieve desired commanded volume over time.

Abstract: A diaphragm and chamber device including chamber means for defining a chamber having fixed position walls on opposite sides, a diaphragm in the chamber and sealably mounted between the walls to define first and second regions therein on opposite sides of the diaphragm, the diaphragm being movable in the chamber so as to change the volume of the two regions as the diaphragm moves toward either the wall, a magnet carried by the diaphragm and movable therewith, and a magnet position sensor carried by a the wall and sensing the location of the magnet and thus the diaphragm.

Abstract: A diaphragm for use in a fluid flow chamber comprising a generally flat flexible sheet that is engageable at its periphery and has a central portion that is reciprocally movable along an axis perpendicular to a plane through the periphery, the flexible sheet having annular corrugations around the center portion, and a magnet secured to the center of the sheet, the magnet having a front and a rear, the corrugations causing the front and rear to maintain their orientation with respect to the axis as the central portion travels along the axis.

Abstract: A fluid flow chamber cassette that can be mounted with either its front wall or rear wall against a supporting machine and has a flexible tube that extends from a sidewall and forms a loop that is symmetrical about a loop axis that is transverse to the side wall so that the loop will be acted upon by a pump roller on the machine both when the front wall is against the machine and when the rear wall is against the machine. Also disclosed is automatically fixing the initial liquid levels and amounts of air in venous and arterial chambers of fluid flow transfer device apparatus by having the arterial chamber inlet enter the arterial chamber at a position higher than the arterial chamber outlet, having the venous chamber inlet enter the venous chamber at a position higher than the venous chamber outlet, and priming the apparatus by causing reverse flow, so that the liquid rises in the venous and arterial chambers to the level of the entrances of the inlets.

Abstract: Fluid flow apparatus comprising a housing defining a chamber and having an inlet and outlet for liquid flowing into and out of the chamber, an electrically-powered heater located in the chamber, a temperature sensor mounted to sense temperature of liquid prior to entering the chamber and providing inlet temperature signals indicating inlet temperature, and a controller electrically connected to receive the inlet temperature signals from the temperature sensor and to control a duty cycle of the heater in response to the inlet temperature signals.

Abstract: Apparatus for displacing a piston in a chamber comprising a support member, a motor including a housing and a driving member that rotates relative to the housing and a driving axis, the driving member being rotatably mounted with respect to the support member, a torque resistor between the motor housing and the support limiting relative rotation between the two except when the torque between the two exceeds a predetermined amount, a piston driver including a driven portion threadedly connected to the driving member and a displacement portion that is axially displaced in response to relative rotation between the driving member and the driven portion, and a housing rotation detector to detect when the housing rotates relative to the support, indicating resistance to axial movement of the piston driver.

Abstract: A fluid flow chamber including a housing defining a chamber, a chamber inlet and a chamber outlet for flow of liquid therethrough, a float in the chamber, and a magnet and magnetic position sensor, one of which is carried by the float for movement with the change in liquid level in the chamber, the other of which is fixedly mounted with respect to the housing.

Abstract: A heat exchanger useful for example in medical applications has a plurality of parallel abutting channels separated by a sheet through which heat is exchanged, with the channel-defining walls preferably in line contact with the sheet and with sharp changes in direction rendering a generally serpentine flow pattern in each channel.

Abstract: A cell for remotely sensing conductivity of a fluid passing through it, the cell having an inlet and an outlet and two fluid paths between the two, thereby defining a fluid loop, an excitation transformer comprising a first toroidal core having a hole through it and wire turns around it, the core encompassing a portion of the fluid loop therein, and a sensing transformer comprising a second toroidal core having a hole through it and wire turns around it, the core encompassing a portion of the fluid loop, the cores being coplanar to thereby reduce leakage between the transformers.

Abstract: Fluid flow apparatus comprising a housing defining a chamber, a chamber inlet and a chamber outlet for the flow of liquid therethrough, a level sensor providing a control signal having a magnitude related to the level of liquid in the chamber, and a valve hydraulically connected to control flow into the inlet or out of the outlet, and controller operably connected to alternately open and close the valve in a duty cycle responsive to the magnitude of the signal.

Abstract: Centrifuge apparatus for use in separating a heavy phase from a light phase in a rotating bowl, the apparatus comprising means defining a channel forming a continuous loop and having an inlet, a first outlet, and a dam portion spaced along the channel from the inlet and having an inner wall radius that is greater than that of adjacent portions so as to provide a heavy phase dam region which can be completely filled with separated heavy phase so as to prevent separated light phase from flowing past it.

Abstract: A two-piece electrical connection assembly comprising a first connector comprising a first insulating housing carrying plural first contacts in close proximity in a row, and a second mating connector for making connection between wires of a multiple conductor cable and said first contacts of said first connector, said second connector comprising a second insulating housing providing means for supporting second contacts aligned with said first contacts for mating with them and providing a spacing member, elongated second contacts having contact portions in position for mating with first contacts, connecting end portions connected to said wires, and spaced portions between said contact portions and said end portions and spaced from adjacent spaced portions by said spacing member, and heat shrunk plastic tubes surrounding the ends of said wires and said connecting end portions up to locations on said second contacts sufficiently close to said spacing member for the contacts to be spaced from each other, said tub

Abstract: A pinch valve employing first and second linear solenoids in series so that the first solenoid closes a flexible tube when powered, and the second solenoid is positioned to be pushed by a spring, to in-turn push the driving member of the first solenoid in a loss-of-power condition, and is positioned to be moved away from the first solenoid when powered so that the first solenoid is free to selectively close or open the tube.

Abstract: A flow-through chamber for conveying blood including an elongated container having sides, a top and a bottom for mounting with its longitudinal axis in a vertical orientation, an inflow tube formed integrally with the container, extending vertically along a side of the container and entering the container through a chamber inlet at a flow direction transverse to the longitudinal axis and at a location spaced from the bottom of the chamber, and an outflow tube formed integrally with the chamber, extending vertically along a side of the container and entering the container at its bottom at a chamber outlet.

Abstract: Apparatus for supporting a fluid flow cassette having an opening for receiving a sensor, the apparatus including a sensor mounted on a support, means to lock the cassette into an insertion position with its opening aligned with but spaced from the sensor along an insertion axis, means to move the sensor relative to the opening to cause the sensor and opening to be brought together, and means to prevent the sensor and opening from coming close enough for the sensor to sealably engage the opening until after the cassette has been locked into the insertion position.

Abstract: A peristaltic pump comprising a removable platen having a cylindrical passage about a platen axis, a flexible tube mounted on the inner surface and forming a loop around the platen axis, a rotor mounted on and extending from a housing for rotation about the platen axis, and a roller mounted on the rotor so as to squeeze the tube against the platen as the rotor rotates, the roller having an axis that is at an angle relative to that of the platen axis to cause the platen to be biased in the direction of the platen axis by the roller as the rotor rotates.

Abstract: A fluid flow chamber cassette that can be mounted with either its front wall or rear wall against a supporting machine and has a flexible tube that extends from a sidewall and forms a loop that is symmetrical about a loop axis that is transverse to the side wall so that the loop will be acted upon by a pump roller on the machine both when the front wall is against the machine and when the rear wall is against the machine. Also disclosed is automatically fixing the initial liquid levels and amounts of air in venous and arterial chambers of fluid flow transfer device apparatus by having the arterial chamber inlet enter the arterial chamber at a position higher than the arterial chamber outlet, having the venous chamber inlet enter the venous chamber at a position higher than the venous chamber outlet, and priming the apparatus by causing reverse flow, so that the liquid rises in the venous and arterial chambers to the level of the entrances of the inlets.

Abstract: A perfusion device, such as an oxygenator including a parallel plate membrane consisting of an accordian-folded elongated sheet, is provided with a plurality of perfusion compartments, each with its own inlet and outlet, so that a greater or lesser perfusion membrane area may be used, as desired.