The invention related to a delivery head for delivering a liquid drop by drop comprising an end-piece (14) pierced with a channel for the expulsion of the liquid (32) through which air also enters back in the reverse direction.In the end-piece, at the downstream end of the expulsion channel, it comprises a valve operating as a non-return valve with respect to the flow of the liquid being expelled. The valve movable stopper (34) is so made that it let air flow through when itis applied on its seat (36) in a closed position of the valve obturating the expulsion channel, said valve thence ensuring an anti-bacterial filtration on the air entering back.本發明係關於一種用於逐液滴地遞送一液體之遞送頭部，該遞送頭部包含經穿通有用於排出該液體之一通道(32)的一端件(14)，空氣亦在相反方向上通過該通道而向後進入。在該端件中，在該排出通道之下游末端處，該端件包含關於所排出之該液體之流而操作為一止回閥的一閥。閥可移動制動器(34)經製造成使得其在其於閉塞該排出通道的該閥之一關閉位置中應用於其底座(36)上時讓空氣流動通過，該閥由此確保對向後進入之該空氣的一抗菌過濾。
