US Patent 9169940 Purge line changing block joint and fluid control apparatus

A purge line changing block joint for enabling supply of different types of purge gas between lines without a significant remodeling of a fluid control apparatus and the fluid control apparatus is provided. A purge line changing block joint is connected to an upper side of a three-way valve channel portion in at least one line of the plurality of lines. The purge line changing block joint includes a process gas inlet channel communicating with a process gas inlet channel of the three-way valve channel portion, an outlet channel communicating the process gas inlet channel and an outlet channel of the three-way valve channel portion, a channel terminal not in communication with a purge gas inlet channel of the three-way valve channel portion but terminating the same, and a new purge gas inlet channel communicating with the outlet channel and opening on the top surface.