Aspirating syringe

• US 5,395,345 A
• Filed: 01/27/1994
• Issued: 03/07/1995
• Est. Priority Date: 01/27/1994
• Status: Expired due to Term

• Current Assignee: The Kendall Company (Colgate-Palmolive Company)
• Original Assignee: The Kendall Company (Colgate-Palmolive Company)
• Inventors: Gross, James R.
• Primary Examiner(s): YASKO JR, JOHN D
• Application Number:
  US08/186,944
• Time in Patent Office: 404 Days
• Field of Search: 604/187, 604/218, 604/220, 604/221, 604/223, 604/230, 128/763-765
• US Class Current: 604/187
• CPC Class Codes: A61B 10/0233 Pointed or sharp biopsy instruments
• CPC Class Codes: A61B 10/025 for taking bone, bone marrow or cartilage samples
• CPC Class Codes: A61M 5/3148 Means for causing or aiding aspiration or plunger retraction

Abstract

The invention features an aspirating syringe which includes a plastic syringe barrel having an exterior wall and an inner surface, and leading and trailing ends. The inner surface and ends define a hollow interior chamber and a predetermined volume. The leading end of the barrel has an opening extending through a hub and the trailing end terminates at an outer rim. The syringe also includes a plastic plunger slidingly operative in the barrel. The leading, i.e., sealing, end of the plunger helps to define the hollow interior chamber and the predetermined volume. The plunger extends longitudinally within and beyond the barrel trailing end and is movable in the barrel inwardly toward the leading end and outwardly away from the leading end, thereby varying the predetermined volume of and pressure within the barrel interior chamber. The plunger also has a sealing end receivable inside the barrel to substantially seal the hollow interior chamber and a thumb-receiving end outside the barrel. The syringe includes a finger grip member extending perpendicular from the barrel trailing end. An outward biasing means is coiled around the plunger between the barrel trailing end and the plunger thumb-receiving end to bias the plunger outwardly from the syringe barrel upon advancement of the plunger into the barrel.

Claims

1. An aspirating syringe, comprising;

(a) a plastic syringe barrel having an exterior wall and an inner surface, and a leading and a trailing end, said inner surface and said ends defining a hollow interior chamber and a predetermined volume, said leading end having an opening extending through a hub, said trailing end terminating at an outer rim;

(b) a plastic plunger operative in said barrel through said barrel trailing end to define said hollow interior chamber and said predetermined volume, said plunger extending longitudinally within and beyond said barrel leading end and being movable in said barrel inwardly toward said leading end and outwardly away from said leading end, thereby varying the volume of said barrel interior chamber, said plunger having a sealing end receivable inside said barrel to substantially seal said hollow interior chamber and a thumb-receiving end outside said barrel, wherein said plunger sealing end comprises an elastomeric gasket comprising a body with forward and rearward ends and first and second annular flanges positioned circumferentially at the forward and rearward ends of the body, the flanges being separated by an annular space intermediate the body portion and the barrel inner surface, wherein the gasket further comprises an annular projection extending from each flange, each projection being of reduced thickness relative to the thickness of each flange and providing a contact point with the barrel inner surface when said plunger sealing end is received in said barrel chamber, thereby enabling low friction between said gasket and said barrel inner surface during forward and rearward movement of said gasket; and

(c) an outward biasing means coiled around said plunger between said barrel trailing end and said plunger thumb-receiving end to bias the plunger outwardly from the syringe barrel upon advancement of the plunger into said barrel.

2. The aspirating syringe of claim 1, said outward biasing means comprising a spring.

3. A method of aspirating a bodily specimen, comprising

providing the syringe of claim 1 in operative association with a needle and arranged with pressure applied to the thumb-receiving end of the syringe such that the plunger is positioned well within the barrel;

inserting the needle into a patient;

relieving sufficient pressure on the thumb-receiving end to allow the syringe plunger to retract sufficiently to aspirate a specimen from the patient into the needle; and

removing the needle from the patient.

4. The method of claim 3, further comprising

re-applying sufficient pressure to the thumb-receiving end of the syringe to eject the specimen from the needle.

5. The aspirating syringe of claim 1, further comprising a finger grip member extending perpendicular from said barrel trailing end.