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AssigneeBaxter Travenol Laboratories, Inc.
InventorNick Zissimopoulos
Estimating the term…
Improvements in infusion controlling apparatus used in limiting the flow rate of an intravenous solution to a patient. The improvements provide coarse and fine orientations of a casette through which the solution passes relative to a controller which valves the casette's inlet and outlet to provide measured volumes of fluid. The coarse alignment device includes spaced apart metal sections which grasp onto the casette and move it towards the controller's valving members. As the casette reaches the valving members, protuberances on the controller fit into indentations on the casette, as the fine adjustment. The indentations into which the protuberances fit form part of the casette's base section of plastic notwithstanding the location of a cover slip between these two items. The valving members couple to a rocker arm which pivots about a point located at its middle and has magnetic poles at its ends. The rocker arm's pivot point over the center leg of an E-frame electromagnet allows the arm to rotate between two orientations in which one of its magnetic poles contacts a side leg of the E-frame electromagnet. Current passing through a coil located on the center leg of the electromagnet moves the rocker arm between these positions, depending upon the current's direction. With no current in the coil, the arm's magnets and the E-frame provide a bistable magnetic device in which the rocker arm forces one of the valving members to close either the casette's inlet or its outlet. This prevents the uncontrolled passage of fluid through the casette to the patient.
In a controller for use with a casette having:
In a controlled volume administration set for liquids, adapted to retain and hold a casette which defines a liquid flow path passing on one side of a flexible membrane, and upstream and downstream valve apertures to permit valving members to pass through said casette to alternatively and releasably press against said membrane to block liquid flow through said flow path, the improvement comprising a rocker arm which carries said valving members and is movable to cause said valving members to alternatively block and permit flow through said flow path, said rocker arm carrying a separate permanent magnet at each end, said permanent magnets being disposed so that their respective poles of opposite polarity extend outwardly in generally normal relation to the rocker arm, and electromagnetic means defining magnetizable ends positioned adjacent to the opposed poles of said permanent magnets, whereby activation of said electromagnet means in one polarity causes the magnetizable ends to assume the same polarity, and said rocker arm to move to place one of said valving members to block said liquid flow, and activation of the electromagnet on the other polarity causes said rocker arm to move to permit the other of said valving members to block liquid flow.
Dependencies are inferred from the claim text.