JPH10309456A - Syringe for liquid ejecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To quickly discharge a bubble entering a syringe by forming a ring groove having a diameter larger than that of a piston and a diamondshaped section in both ends of an inside cylinder of a syringe used for a liquid ejecting device for adhesive, epoxy resin and the like and providing an outlet/inlet port for the liquid on a top part of the ring groove. SOLUTION: Grooves 3, 3' are formed in both sides of an inside cylinder 2 of a syringe 1 and a piston 4 is inserted into the inside cylinder 2. A piston rod 6 is connected to a right side of the piston 4 and the piston rod 6 is made to protrude outward by penetrating a right wall 7 of the syringe 1. Inlet/outlet ports 9, 10 are respectively provided on top parts of the grooves 3, 3'. When the piston rod 6 is pushed to the left side, liquid in the syringe 1 is discharged from the outlet/inlet port 9 and sucked through the inlet/outlet port 10, and a bubble which has entered at this time is suspended in a right chamber 11 of the syringe 1. When the piston rod 6 is drawn to the right side, the bubble within the right chamber 11 flows toward the inlet/outlet port 10, and the bubble is finally discharged through the inlet/outlet port 10 via the grooves 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[Industrial application fields] Liquid ejecting apparatuses such as liquids such as adhesives, epoxy resins and acrylic resins, and chemical liquids.

2. Description of the Related Art In a liquid discharging apparatus in which a return syringe and a four-way switching valve are combined, when a piston reciprocates, one side of the syringe handles discharge and the remaining side handles suction. In the case of a small amount of discharge, there is almost no liquid flow due to the small movement of the piston.Therefore, the microbubbles in the inflowing liquid stay in the syringe without flowing out, and grow large while repeating reciprocating movement. In addition, a liquid cushion action is caused, and the liquid gradually flows away even after being discharged from the nozzle, resulting in a liquid dripping phenomenon or discharge of enlarged bubbles, thereby deteriorating the discharge accuracy.

[Problems to be Solved by the Invention] The shape of a syringe inner cylinder is improved so that bubbles flowing into a syringe are promptly discharged to a discharge pipe line so that bubbles do not grow in the syringe.

[Means for Solving the Problems] At both ends of a syringe inner cylinder, the diameter is sufficiently larger than the outer diameter of the piston.
In addition, a リ ン グ -shaped ring groove is formed, a liquid inlet / outlet port is provided at the top of the ring groove, and a syringe is horizontally installed with the inlet / outlet port facing upward to constitute a liquid discharging apparatus.

[Action] The left and right moving ends of the piston are moved to a position just before the piston enters the escape groove. At the time of inhaling the liquid, the air bubbles flowing into the syringe or the generated air bubbles are floating in the syringe. Next, when the movement of the piston is switched and the liquid is discharged, the bubbles are pushed out into the escape groove and gather at the top along the slope of the escape groove. As the liquid is discharged, the bubbles are discharged to the discharge conduit.

[Effect] Since the bubbles do not become large, there is no cushioning effect of the liquid and no dripping occurs. Since large bubbles do not enter the liquid, the ejection accuracy does not deteriorate.

[Embodiment 1] The syringe 1 has ◇ -shaped relief grooves 3 and 3 ′ formed on both sides of an inner cylinder 2. The piston 4 slides inside the inner cylinder 2 and is hermetically sealed by a seal 5. Piston 4
Is connected to a piston rod 6, penetrates through the right wall 7 of the syringe 1, and protrudes outside, and is sealed by a seal 8. An access port 9 is provided at the top of the groove 3 and an access port 10 is provided at the top of the groove 3 '. When the piston rod 6 is pushed to the left, the liquid in the syringe 1 is discharged from the inlet / outlet port 9 and sucked through the inlet / outlet port 10. At this time, the air bubbles that have flowed float on the upper side of the right chamber 11 of the syringe 1. Piston rod 6
Is drawn to the right, the liquid in the right chamber 11 is discharged from the access port 10. At this time, the air bubbles in the right chamber 11 flow toward the entrance port 10 along the slope of the groove 3 '. When the piston 4 is placed at the rightmost end of the right chamber 11, all the bubbles are pushed into the groove 3 ', float up, and are discharged from the inlet / outlet port 10 to the outside of the syringe. In the right chamber 12 as well, when the piston 4 moves to the left, air bubbles are released from the access port 9 by the same action. Piston 4
If the O-ring 5 is inserted into the grooves 3 and 3 ', the air-tight action of the O-ring 5 is lost, the right chamber 11 and the left chamber 12 communicate with each other, and the liquid can flow between the inlet / outlet ports 9 and 10, and the inside can be easily cleaned. Can be done. As described above, air bubbles are quickly discharged without stagnating in the syringe 1 and do not affect the discharge accuracy, so that high-precision discharge is measured and no liquid dripping occurs.

[0008]

[Brief description of the drawings]

FIG. 2 is a cross-sectional view of the syringe according to the first embodiment of the present invention. 1, syringe 2, inner cylinder 3, groove 4, piston 5, seal 6, piston rod 7, right wall 8, seal
9, In / out port 10, In / out port

Claims (1)

[Claims] 1. A ring groove having a diameter sufficiently larger than an outer diameter of a piston and formed in both ends of an inner cylinder of a syringe is formed,
A syringe for a liquid discharge device, wherein a liquid inlet / outlet port is provided at the top of the ring groove.