A kind of improvement of remaining needle of this case system,It includes a control valve and a delivery conduit,The control valve has a radial valve body for opening up a valve chamber,Relatively extend on the same axis of valve chamber circumferential surface what and be connected to one first adapter tube and one second adapter tube,And the valve chamber is socketed a sealing-plug,The sealing-plug axially open up one can be aligned and be connected to what this first,The perforation of second adapter tube,And what sealing-plug top axially extending at least valve handle of circumferential surface； The delivery conduit Hou side has a joint portion for being hinged with first adapter tube,And front then axially extending one for be infused by soft needle section； By stirring the valve handle,Make the interior rotation of the sealing-plug what valve chamber,And enable the perforation and this first,Second adapter tube forms the connected state on the same axis of position what,Or enable the perforation and this first,Second adapter tube forms the dissengaged positions for deviateing masking.本案係一種留置針之改良，其包括一控制閥及一輸送導管，該控制閥具有一徑向開設一閥室之閥體，該閥室周面於同一軸線上相對地延伸與連通一第一接管及一第二接管，且該閥室套接一密封塞，該密封塞軸向開設一可對齊且連通於該第一、第二接管之穿孔，並於該密封塞頂部周面軸向延伸至少一閥柄；該輸送導管後方具有一接裝該第一接管之接合部，而前方則軸向延伸一可供輸液通過之軟質針段；藉由撥動該閥柄，使該密封塞於該閥室內轉動，而令該穿孔與該第一、第二接管形成位於同一軸線上的連通狀態，或者令該穿孔與該第一、第二接管形成偏離遮蔽的切斷狀態。
