Connection member, injection device and pump casing equipped with connection member, and liquid verification method using connection member

A connection member to be provided between a pump for pressurizing and feeding liquid and a suction tube for connecting a suction port of the pump with the suction tube, and between the pump and a discharge tube for connecting a discharge port of the pump with the discharge tube, comprising:

• a pump attachment part which includes a suction opening for connection with the suction port and a discharge opening for connection with the discharge port, and which is attached with the pump in a state where the suction port is connected to the suction opening and the discharge port is connected to the discharge opening;
• a tube connecting part including a suction connecting section for connecting the suction tube and a discharge connecting section for connecting the discharge tube;
• and
• a flow passage defining part including a suction passage section and a discharge passage section, the suction passage section connecting the suction opening of the pump attachment part and the suction connecting section of the tube connecting part with each other so as to flow the liquid between the suction opening and the suction connecting section, and the discharge passage section connecting the discharge opening of the pump attachment part and the discharge connecting section of the tube connecting part with each other so as to flow the liquid between the discharge opening and the discharge connecting section, wherein
• at least a portion of each of the suction passage section and the discharge passage section includes a membrane deformable due to pressure of the liquid flowing in the suction passage section and the discharge passage section, and
• the flow passage defining part has a shape allowing the flow passage defining part to be attached to a sensor for detecting a flow state of the liquid flowing in the suction passage section and the discharge passage section by deformation of the membranes in an arrangement that the membranes face the sensor.