PISTON PUMP WITH VARIABLE BUFFER

摘要

The invention comprises a breast pump apparatus comprising a vacuum pump and a variable-volume buffer volume coupled together in fluid communication. The apparatus also includes a breast-receiving portion coupled to the vacuum pump and the buffer volume such that the vacuum pump is operable to generate negative pressure at the breast- receiving portion to stimulate milk expression, and the negative pressure generated at the breast-receiving portion can be controlled by controlling the buffer volume.