A drip rate regulating device, includes a screw joint connected to a liquid input conduit, and a spiral sleeve that can adjust the liquid flow rate and connect to the liquid output conduit. When the spiral sleeve movable nut is engaged with the screw of the screw joint, the metal fine core inside the spiral sleeve is gradually inserted into the metal capillary inside the spiral joint, so that an annular cylindrical passage is formed between the inner wall of the metal capillary and the metal fine core. When the liquid flows through the annular cylindrical passage, the viscous force generated by the liquid and the surface of the annular cylindrical passage will slow down the liquid flow rate； when the movable nut is screwed into the screw joint, the depth of the metal fine core inserted in the metal capillary will changes, and the length of the annular cylindrical passage will changes, thereby the liquid flow rate will changes.一種滴注速率調整裝置，係包括一連接在液體輸入導管之螺旋接頭，及一可以調整液體輸出速度，並連接液體輸出導管之螺旋套管。當螺旋套管活動螺帽與螺旋接頭之螺牙接合時，帶動螺旋套管內部之金屬細蕊逐漸插入螺旋接頭內部之金屬毛細管內，使金屬毛細管內壁與金屬細蕊間形成一環形柱狀通道。當液體流經此一環形柱狀通道時，液體與環形柱狀通道表面產生之黏滯力將減緩液體通過的速度；當調整活動螺帽旋入螺旋接頭螺牙圈數時，金屬細蕊插入金屬毛細管之深度隨之變化，同時改變環形柱狀通道之長度，藉此改變液體通過的速度。
