Diaphragm valve incorporating an alarm port

A weir-type diaphragm valve operable to selectively enable liquid flow between two pipelines while directing a portion of the flowing liquid to an external pipeline, said valve comprising:

• a valve body comprising:
• a diaphragm chamber with a concave weir extending across said chamber and having an upper surface with a bottom vertex, wherein said diaphragm chamber has a lateral plane spanning along said upper surface of said weir such that it borders between an upstream side of said diaphragm chamber and a downstream side of said diaphragm chamber;
• and
• an alarm port for enabling liquid communication between said diaphragm chamber and an exterior of the valve body to which said external pipeline is configured to be connected;
• and
• a diaphragm being deformable within said diaphragm chamber between a closed state in which a sealing surface of the diaphragm covers a resting portion of the diaphragm chamber including said upper surface of the weir, thereby preventing liquid from flowing between said pipelines, and an open state in which said sealing surface is spaced at least from said bottom vertex, thereby enabling liquid to flow between said pipelines;
• wherein said alarm port is entirely formed on said resting portion and outside said lateral plane, and is spaced from said bottom vertex, so as to be sealed by said sealing surface of said diaphragm at said closed state, and be unsealed thereby at said open state;
• and
• wherein said upper surface of said weir is defined symmetrically with respect to said lateral plane, and said alarm port is formed in an auxiliary surface of said resting portion, at least partially outside said upper surface of said weir, yet formed flush therewith.