Transfer valve manifold

A transfer valve manifold comprising:

• at least one transfer valve installation surface on which a pilot transfer valve is installed;
• a supply and ejection ports common to each transfer valve that are in communication with a supply and ejection through-holes on said installation surface and that supply and eject a control fluid to and from each transfer valve through these through-holes;
• a pilot supply channel common to each transfer valve that is in communication with a pilot through-hole on said installation surface and that supplies pilot fluid to each transfer valve through the pilot through-hole;
• an internal pilot channel branching off from said supply port;
• an external pilot port that introduces pilot fluid from the exterior and an external pilot channel leading to the external pilot port;
• and
• pilot fluid switching means provided between said internal and external pilot channels and said pilot supply channel for selectively guiding pilot fluid from either the internal or external pilot channel,
• wherein said pilot fluid switching means includes a shuttle valve having two input openings, one output opening, a valve chamber into which the input and output openings are opened, and a shuttle valve member accommodated in the valve chamber and operating by means of the pressure of pilot fluid flowing in from said input openings to always connect the input opening on a higher-pressure side to the output opening while closing the input opening on a lower-pressure side, and wherein said two input openings are individually connected to the internal and external pilot channels while the output opening is connected to the pilot supply channel.