| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a liquid jetting device free from functional deterioration of a pump or liquid leakage due to pump operation and easy to assemble. <P>SOLUTION: The liquid jetting device has a pump unit provided with: a cylindrical body 6 fittingly held by a head 3; a head cylinder 5 forming an internal path r communicating with the head 3 by opening the lower end 5e drooping from the cylindrical body 6; and the first and second piston plungers 11 and 12 having a valve body 11a which can open or close a squeezing hole 8 formed inside the head cylinder 5 and slidably held inside the head cylinder 5 by the annular seal parts 12a and 12b formed around the valve body 11a. The outer edge E of an opening A formed on the lower end of the head cylinder 5 is formed on the inner peripheral face 5f thereof, wherein the outer edge E is larger than the tip diameter ϕ<SB POS="POST">12a</SB>of the seal portion of the second piston plunger 12 but smaller than the inner diameter ϕ of the head cylinder. Further, there is provided an inclined face 5s connecting to the inner peripheral face 5f while reducing diameter from the outer edge E toward the head 3. <P>COPYRIGHT: (C)2012,JPO&INPIT |
