Flow-rate controller, and regulator unit and valve unit used for the same

A flow-rate controller comprising:

• a regulator unit with a fluid channel having a first body provided on a first base, a regulator provided on the first body, and a first pressure detection device;
• a valve unit with a fluid channel having a second body provided on a second base, a flow-rate control valve provided on the second body, and a second pressure detection device;
• and
• an orifice unit that is connected to the regulator unit and the valve unit in a detachable manner and that has a fluid channel and an orifice that connect to the regulator unit and the valve unit,
• wherein the orifice unit includes,
• a tube portion constituting the fluid channel,
• an orifice integrally provided in the tube portion without a joint,
• a joint structure that directly connects an end of the tube portion to the regulator unit or the valve unit,
• wherein the orifice unit is not directly connected to any one of the first base and the second base,
• wherein the joint structure and the tube portion are integrated,
• wherein the first base includes a first fixing portion,
• wherein the second base includes a second fixing portion,
• wherein the first fixing portion and the second fixing portion are fixed to each other in a detachable manner, and wherein
• the valve unit further comprises a compression coil spring interposed between a sliding part and cover flange that is designed to urge the sliding part in a direction of fluid force acting on a diaphragm needle.