| 摘要 |
PROBLEM TO BE SOLVED: To provide a liquid injection device suppressing unnecessary flowing of protrusion portion molten at the time of thermal caulking to a flow passage member side and being capable of preventing a communication hole from being blocked.SOLUTION: A liquid injection device comprises: a flow passage member (59) having a communication hole (73) where liquid circulates through; a unit member (50) formed with a liquid flow passage (51) communicating with the communication hole (73) therein with the flow passage member (59) fixed to an opening portion of the liquid flow passage (51) in a state of the liquid flow passage (51) and the communication hole (73) communicating with each other; a protrusion portion (77) protruded around the flow passage member (59) in the unit member (50); and a relief portion (78) being provided to the unit member (50) and retreating to an opposite side to a protrusion direction of the protrusion portion (77) than an inlet of the communication hole (73) in the flow passage member (59) at an opposite side to the communication hole (73) with the protrusion portion (77) interposed therebetween. The flow passage member (59) is fixed to the unit member (50) by melting of the protrusion portion (77).SELECTED DRAWING: Figure 7 |
