Apparatus for drawing liquid such as blood

Claim 2

Apparatus suitable for drawing blood samples comprising: a piston; a piston rod rigidly connected to and coaxially extending from said piston; a tubular support means coaxially arranged with respect to and supporting said piston by way of said piston rod; an inlet tube means supported by said support means and providing a passage communicating with the interior of said support means; a container having a bore adapted to slideably receive said piston and with said piston defining a receiving chamber; sealing means extending around the periphery of said piston to sealingly engage said bore; first and second axially extending passages communicating with said receiving chamber; and a sleeve means mounted between said piston and said support means for movement relative thereto between first and second positions; said sleeve means when in said first position facilitating communication of said inlet tube passage with said receiving chamber by way of said first axially extending passage and closing said second axially extending passage; said sleeve means when in said second position facilitating communication between the environment outside said apparatus and said receiving chamber by way of said second axially extending passage and closing said first axially extending passage.

Claim 3

Apparatus as claimed in claim 8 further comprising interengaging means on the container and the sleeve means for providing a releasable engagement between the container and the sleeve means enabling the sleeve means to be manually rotated by the container between said first and second positions.

Claim 4

Apparatus as claimed in claim 4 wherein the interengaging means comprises guide track means on the support means and track engaging means on the container allowing for axial displacement of the container in relation to the support means in two different angular positions of the container and rotational movement of the container in relation to the support means between said two different angular positions in at least two axially spaced positions of the container.

Claim 5

Apparatus as claimed in claim 3 further comprising means in the guide track means allowing for displacement of the container in one axial direction only in at least one of said angular positions and in one rotational direction only in one of said axially spaced positions and in the opposite rotational direction only in the other one of said axially spaced positions.

Claim 6

Apparatus for drawing blood comprising: a plunger; support means supporting the plunger at one end thereof; an inlet pipe for said blood supported by the support means; a longitudinally extending container, open at one end, of substantially uniform cross sectional area over at least a substantial part of its length from the open end, displaceably receiving the plunger; means on the plunger sealingly engaging the inner surface of the wall of the container; said plunger defining a blood receiving passage opening at the inlet pipe and at the other end of the plunger to provide communication between the inlet pipe and said other end of the plunger; said plunger further defining a vent passage opening opening at said other end of said plunger and at said support means to provide communication between the interior of said container and the surrounding air; and a sleeve means controlling communication through said blood receiving passage and said vent passage to keep one of these passages open aNd the other closed, and vice versa; the container being axially movable on the plunger to form together therewith a cylinder piston type pump adapted when the sleeve means keeps said blood receiving passage open to draw blood through said inlet pipe and said blood receiving passage into said container.

Claim 7

Apparatus for drawing blood comprising: a plunger; support means supporting the plunger at one end thereof; an inlet pipe for said blood supported by the support means; a longitudinally extending container, open at one end, of substantially uniform cross sectional area over at least a substantial part of its length from the open end, displaceably receiving the plunger; means on the plunger sealingly engaging the inner surface of the wall of the container; said plunger defining a blood receiving passage opening at the inlet pipe and at the other end of the plunger to provide communication between the inlet pipe and said other end of the plunger; said plunger further defining a vent passage opening opening at said other end of said plunger and at said support means to provide communication between the interior of said container and the surrounding air; and a sleeve means controlling communication through said blood receiving passage and said vent passage to keep one of these passages open aNd the other closed, and vice versa; the container being axially movable on the plunger to form together therewith a cylinder piston type pump adapted when the sleeve means keeps said blood receiving passage open to draw blood through said inlet pipe and said blood receiving passage into said container.