Threaded nut syringe plunger for use with a medication infusion pump
First Claim
1. In an infusion pump system including an infusion pump having a pump housing defining a syringe compartment for receiving and supporting a syringe, and an access door movable between open and closed positions, said syringe having a syringe barrel and a plunger received therein, said pump including a lead screw and means for controllably driving said lead screw, the improvement comprising:
- an open-sided and internally threaded half nut carried by said plunger for threadably engaging said lead screw whereby rotation of said lead screw advances said plunger relative to said barrel to deliver medication from said syringe;
said half nut further including detent means for snap-fit engagement with said lead screw to retain said half nut in threaded engagement with said lead screw.
1 Assignment
0 Petitions
Accused Products
Abstract
An improved syringe is provided for use in a medication infusion pump for operating the syringe to administer a selected medication to a patient. The syringe comprises a hollow barrel adapted to receive a supply of the selected medication for delivery through infusion tubing or the like to the patient, in combination with a syringe plunger formed with an open-sided threaded half nut for engaging a motor-driven lead screw of the medication infusion pump when the syringe is correctly seated within a syringe compartment formed within a pump housing. The half nut on the syringe plunger includes detent tabs for snap-fit engagement with the pump lead screw to provide a direct drive connection therebetween. A compartment door on the pump housing can be moved to a closed position, following syringe placement into the syringe compartment, only when the plunger half nut is properly engaged with the lead screw.
345 Citations
17 Claims
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1. In an infusion pump system including an infusion pump having a pump housing defining a syringe compartment for receiving and supporting a syringe, and an access door movable between open and closed positions, said syringe having a syringe barrel and a plunger received therein, said pump including a lead screw and means for controllably driving said lead screw, the improvement comprising:
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an open-sided and internally threaded half nut carried by said plunger for threadably engaging said lead screw whereby rotation of said lead screw advances said plunger relative to said barrel to deliver medication from said syringe; said half nut further including detent means for snap-fit engagement with said lead screw to retain said half nut in threaded engagement with said lead screw. - View Dependent Claims (2, 3, 4, 5, 6)
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7. An infusion pump system, comprising:
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a syringe having a syringe barrel adapted to be filled with a selected medication, and a syringe plunger slidably received into said barrel and movable therein to deliver the medication therefrom; said syringe plunger comprising an elongated piston rod having a rear end projecting from said barrel, and an open-sided and internally threaded half nut carried by said piston rod generally at said rear end thereof; and an infusion pump including a pump housing defining a syringe compartment for receiving and supporting said syringe, and drive means for engaging and controllably moving said plunger to deliver the medication from said syringe, said drive means including a rotatably driven lead screw; said half nut including detent means for snap-fit engagement with said lead screw to retain said half nut in threaded engagement with said lead screw. - View Dependent Claims (8, 9, 10, 11, 12)
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13. A syringe for use with a medication infusion pump having a rotatable lead screw for controllably dispensing medication from said syringe, said syringe comprising:
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a hollow syringe barrel adapted for receiving and supporting a supply of a selected medication; and a syringe plunger slidably received into said barrel and movable therein to deliver the medication therefrom; said syringe plunger comprising an elongated piston rod having a nose end slidably received within and sealingly engaging said barrel, said piston rod projecting from said nose end and terminating in a rear end disposed outside said barrel, said piston rod further including an open-sided and internally threaded half nut carried thereon generally at said rear end thereof, said half nut including detent means for snap-fit engagement with the lead screw of the infusion pump to releasibly retain said half nut in threaded engagement therewith. - View Dependent Claims (14, 15, 16, 17)
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Specification