FLUID CONTAINER POSITIONING SYSTEM

1 . A mechanism for positioning a fluid container supported on a movable carrier at a predetermined location, wherein the mechanism comprises:

a container positioning ramp located adjacent to a portion of the moveable carrier and configured to be contacted by a bottom portion of a container supported on the movable carrier when the movable carrier moves the container to the predetermined location; and

a container hold down arm configured for selective movement relative to the container positioned at the predetermined location, wherein the container hold down arm is configured to contact a top portion of the container positioned at the predetermined location and push the container down so that the bottom portion of the container maintains contact with the container positioning ramp.

2 . The mechanism of claim 1 , wherein the container positioning ramp comprises a sloped first end, a level center portion, and a sloped second end, and wherein the container is positioned on the level center portion when the container is positioned at the level-sensing location.

3 . The mechanism of claim 2 , further comprising a roller at the beginning of the sloped first end to guide the bottom portion of a container onto the sloped first end.

4 . The mechanism of claim 1 , further comprising:

a motor;

a threaded rod operatively coupled to the motor; and

a follower block threadably coupled to the threaded rod;

wherein the follower block contacts the container hold down arm to move the container hold down arm from its first position to its second position as the motor moves the follower block.

5 . The mechanism of claim 4 , wherein the movable carrier is contained within a housing having a top wall over the carrier, and wherein a container access opening is formed through the top wall above the predetermined location and configured to permit a fluid transfer probe, or tip removably attached to the fluid transfer probe, to enter a container located beneath the container access opening, and wherein the mechanism further comprises:

a shutter plate attached to the top wall and movable between a first position covering the container access opening and a second position exposing the container access opening, wherein the shutter plate is operatively coupled to the motor to effect powered movement of the shutter plate from the first position to the second position as the motor moves the follower block to move the container hold down arm from its first position to its second position.

6 . The mechanism of claim 1 , wherein the movable carrier comprises a carousel that is rotatable about a vertically-oriented carousel axis of rotation and including a plurality of container holding stations disposed at angularly spaced positions about the carousel axis of rotation, wherein each container holding station includes spring tabs extending laterally with respect to the carousel axis of rotation and configured to resiliently engage the grooves of a container held in the container holding station to retain the container in the container holding station, and wherein the container is able to slide in a vertical direction between the spring tabs of the container holding station, and wherein

the container positioning ramp is disposed beneath a portion of the carousel and is configured to be contacted by the bottom portion of the container held in a container holding station as the carousel moves the container into the predetermined location,

contact between the container and the container positioning ramp slides the container within the container holding station to a position with the bottom of the container contacting the container positioning ramp, and

the container hold down arm is configured to contact the top portion of the container to slide the container within the container holding station down so that the bottom portion of the container maintains contact with the container positioning ramp.