Abstract: A liquid trap cup and a liquid trap assembly using the same are provided. The liquid trap cup comprises a hollow cup tube with a upper portion and a lower portion, a piston element with a top portion and a tail portion and a liquid discharge structure, in which the piston element is arranged airtight in the lower portion and is movable between a start point and an end point of the lower portion so as to control the opening and the closing of the liquid discharge structure. The liquid trap assembly includes the liquid trap cup and a multi-necked adapter tube with an expanded-plate structure, in which expanded-plate structure can be tightly sealed with the liquid trap. The liquid trap assembly is useful to a breathing system.

Abstract: A liquid trap cup is provided. The liquid trap cup comprises a hollow cup tube with a upper portion and a lower portion, a piston element with a top portion and a tail portion and a liquid discharge structure, in which the piston element is arranged airtight in the lower portion and is movable between a start point and an end point of the lower portion so as to control the opening and the closing of the liquid discharge structure. A liquid trap assembly using the liquid trap cup is provided. The liquid trap assembly comprises said liquid trap cup and a multi-necked adapter tube with an expanded-plate structure, in which expanded-plate structure can be tightly sealed with the liquid trap. When applying the liquid trap assembly to a breathing system, it can simply drain the liquid collected in the liquid trap cup without disassembling the liquid trap assembly so as to prevent the infection problems of patients and reduce the burden of the medical staff.