Patent ID: 8469680

Claim:
A double diaphragm pump comprising a valve body which comprises: a compressed air-filled chamber in a center of the valve body; a compressed air supply port through which compressed air is supplied into said compressed air-filled chamber; a first side wall joined to a first air chamber block that defines a first air chamber and that has at least one first through-hole; a first communication passage communicating between said compressed air-filled chamber and said first side wall; a second side wall joined to a second air chamber block that defines a second air chamber and that has at least one second through-hole; a second communication passage communicating between said compressed air-filled chamber and said second side wall; an annular groove-shaped first air supply chamber formed in said first side wall, said first communication passage and said at least one first through-hole being communicated with each other through said annular groove-shaped first air supply chamber; an annular groove-shaped second air supply chamber formed in said second side wall, said second communication passage and said at least one second through-hole being communicated with each other through said annular groove-shaped second air supply chamber.