Abstract: A transportation mechanism for transporting a test tube rack laterally and intermittently is disclosed. The transportation mechanism includes a test tube rack, one or more fingers and a driving mechanism that drives the finger to move. The finger has a loading state and an unloading state in its movement process. In the loading state, the finger extends upward and into the test tube rack and causes the rack to move laterally. In the unloading state, the finger retrieves downward and out of the test tube rack. Because the finger is driven by the driving mechanism, there is no need to use a restriction metal sheet to press down the finger. As a result, there is no mechanical collision between the finger and the restriction metal sheet, and noise is effectively reduced in the operation.

Abstract: A pneumatic pinch valve assembly having a lever, a piston supporting a pressing piece, and a fluid tube receiving space formed between the lever and the pressing piece for receiving fluid tubes is disclosed. Air is introduced into a cavity to actuate the piston in order to pinch a fluid tube between the lever and the pressing piece to intercept a fluid flow through the tube. A pinching action control feature is located between the piston and the pressing piece and is used to protect the fluid tube by limiting one or more amounts of compression of the fluid tube during operation. The amount of compression of the fluid tube is able to be adjusted so that the fluid tube is not easily deteriorated during long-time operation.

Abstract: The present invention provides a pneumatic pinch valve, comprising: a lever and a pressing piece, a fluid tube receiving space being formed between the lever and the pressing piece, wherein the pneumatic pinch valve further comprises a main body providing a cavity therein, the lever being installed on the main body; a piston provided in the cavity of the main body, the piston engaging with an inner wall of the cavity of the main body so as to divide the cavity into a first cavity and a second cavity, the pressing piece being positioned in the second cavity and supported on the piston; an air inlet port provided at the first cavity, wherein air introduced into the first cavity via the air inlet port moves the piston toward the fluid tube receiving space so as to press the fluid tube through an engagement of the pressing piece on the piston with the lever, and thus intercept the fluid in the fluid tube; and an air discharge mechanism provided at the piston, by which the piston pushes the air introduced into the