Abstract: Sensor cartridges include a fluid constituent-selective sensor membrane in direct sealing contact with a face of a flow-through sample cell in surrounding relationship to a sensor port. The sensor membrane has sufficiently large surface area so as to entirely cover the sensor port and establish an annular region in surrounding relationship thereto. It is this annular region which is in direct contact with a corresponding region of the sample cell face so as to provide self-sealing capabilities. The sensor cartridge most preferably includes a flow-through sample cell having a zig-zag or serpentine flow channel so as to provide a series of sensor ports on both of the opposed cell faces. The faces of the sample cell are most preferably provided with recessed regions which define a series of land surfaces each of which surrounds a respective one of the sensor ports.

Abstract: A mechanism for screw drive and syringe plunger engagement and disengagement for a syringe infusion pump, wherein a split-nut pair are moveable into and out of engagement with a lead screw by means of rotary cam control, the rotary cam being keyed with a crank disk that is coupled to a crank arm, which operates as the syringe plunger mover. The crank arm is rotatable into and out of engagement with the syringe plunger, such rotation also causing the split-nut pair to move into and out of engagement with the lead screw. Index and cam means are carried by the crank arm to aid in proper alignment with the syringe plunger, and a sensor is provided for monitoring proper engagement of the crank arm with the plunger.

Abstract: A pressure diaphragm, wherein at least a portion of an elongate fluid channel is formed diametrically across, and is open through, a flat raised surface of a substantially rigid, disk-like body, and wherein a flexible membrane overlies the raised surface and is sealed to a surrounding flange. The fluid channel communicates with fluid inlet and outlet fittings carried by the body, which are adapted for connection with the tubes of an IV set, and the cross-sectional flow area of the fluid channel is substantially equal to or less than the cross-sectional flow area of any IV tube adapted for connection to the fluid inlet fitting.