PROBLEM TO BE SOLVED: To provide a fluid injection apparatus for injecting droplets in a pulse form at a high speed.SOLUTION: The fluid injection apparatus 100 is for reducing the volume of a fluid chamber provided inside a volume variable chamber by diaphragms 40 and 41 and injecting fluid in the pulse form, and is provided with a tube 80 for supplying liquid to the fluid chambers 62-64 and a fluid injection part 10 disposed at the distal end of the tube 80. In the fluid injection part 10, the plurality of volume variable chambers 21-23 are serially disposed through communicating paths 33 and 35 between an entrance flow path 37 communicated to one end of the tube 80 and an exist flow path 31 communicated to a fluid injection opening 30 for injecting the liquid. The cross sectional area of the exit flow path 31, the communicating paths 33 and 35 and the entrance flow path 37 respectively is smaller than the cross sectional area perpendicular to the liquid flowing direction of the respective fluid chambers 62, 63 and 64.COPYRIGHT: (C)2009,JPO&INPIT【課題】高速でパルス状に液滴を噴射する流体噴射装置を提供する。【解決手段】流体噴射装置100は、容積可変チャンバの内部に設けられる流体室の容積をダイアフラム40,41により縮小して流体をパルス状に噴射する流体噴射装置であって、流体室62~64に液体を供給するチューブ80と、チューブ80の先端に配設される流体噴射部10と、が備えられ、流体噴射部10には、チューブ80の一端に連通する入口流路37と液体を噴射する流体噴射開口部30に連通する出口流路31との間に複数の容積可変チャンバ21~23が連通路33,35を介して直列に配設されている。出口流路31、連通路33,35、入口流路37それぞれの断面積は、流体室62,63,64それぞれの液体流動方向に直角な断面積よりも小さい。【選択図】図2
