Locking device for aspirator, syringe or like instrument

Abstract

An aspirator assembly enabled to remove fluids from a patient comprises an elongated hollow interior barrel, a plunger reciprocally movable within the barrel along the length thereof and extending outwardly from a rear end of the barrel. The plunger includes an elongated stem having a grip at an outer end thereof and a plunger head secured to an inner end of the stem. The plunger head is slidably engagable with an interior surface of the barrel. The improvement is found in a locking device which is selectively positionable into and out of a locked position. The locking device is formed in part on both the barrel and the stem and is adapted for removably locking the plunger head in a plurality of spaced apart locations within and along the length of the barrel. Additionally, the stem may be rotated so as to disengage the locking device and provide an aspirator with unobstructed reciprocation. Furthermore, a threaded stem connects the plunger head to the main plunger stem, so as to allow accurate adjustment of the aspirator volume by turning the handle. A flow control valve is provided at the second end of the barrel which allows selective closing of the end.

Dependencies are inferred from the claim text.