Self-aligned plunger for chromatographic valve

摘要

Plungers and plunger assemblies for a diaphragm-sealed valve are provided. Each plunger is adapted to be received in a passage of the valve body and includes a base member and an upper member having a transversal play in this passage with respect to the base member. A resilient middle element is provided between the upper and base member. The base member is connected to a plunger actuating mechanism within the valve body. The upper member may therefore be self-aligning within the passage.

主权项

1. A diaphragm-sealed valve comprising:
a valve cap having a cap interface; a valve body having a body interface and several cylindrical passages extending in the valve body and opening on said body interface; a diaphragm compressed between the valve cap and the valve body interfaces; several normally-closed and normally-open plungers slidably provided in the respective passages of the valve body, a plunger-actuating assembly comprising:
disk-shape upper and lower pistons located within a circular cavity of the valve body, the lower piston extending under the upper piston contiguously thereto, said pistons being free to rotate relative to the valve body over a given radial distance;an actuator for controlling a distance between the upper and lower pistons for actuating the plungers between closed and open positions, each of said plungers comprising:
a base member operatively linked to one of the lower and upper pistons;an upper member projecting towards said diaphragm; anda resilient middle element provided between the base member and the upper member;said base and upper members being sized, shaped and configured for providing a transversal play between said base and upper members, the transversal play corresponding to the radial distance over which the pistons can rotate, the base member movable between a first position where the base member is coaxial with the upper member and a second position where the base member is not coaxial with the upper member upon rotation of one of the lower and upper pistons within the circular cavity, for preventing slanting of the plungers within their respective passages.