JPH05294395A - Liquid spouting device - Google Patents

Abstract

PURPOSE:To prevent liquid from dripping or roping without spouted liquid left in a nozzle. CONSTITUTION:A nozzle 3 is mounted on the bottom of a liquid storage cylinder 2 and a piston 4 which moves vertically is set in the liquid storage cylinder 2 concentrically with the nozzle 3. A plug 6 is taken in and out of the nozzle 3 from the side face of the nozzle 3. When liquid is spouted, the plug 6 is retracted to open the nozzle 3, and the piston 4 is moved down to spout liquid from the nozzle. At this time, the piston 4 is lowered up to the lower end of the nozzle 3, so that the liquid 8 in the nozzle 3 is completely discharged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid ejection device.
More specifically, the present invention relates to a piston type liquid ejection device that ejects a fixed amount of ejection liquid from a nozzle.

[0002]

2. Description of the Related Art Conventionally, various types of liquid ejection devices have been used. For example, an air pressure type that pushes the discharge liquid from the nozzle by air pressure, a tube type that squeezes the discharge liquid from the nozzle at the tip of the tube by squeezing the tube with a roller, etc., suction of the discharge liquid from the hopper and a nozzle There is known a liquid ejecting device of a piston type, a gear pump type, a valve type, a screw pump type, or the like, which repeatedly extrudes.

All of these are intended mainly for quantitative discharge of the discharge liquid, and have a structure for discharging the discharge liquid continuously or intermittently from the nozzle.

[0004]

However, in each of the liquid ejecting apparatuses of the various types described above, the ejected liquid remains in the nozzle after the ejection of the ejected liquid is completed. Therefore, the following problems have occurred.

The residual liquid remaining in the nozzle spontaneously falls due to its own weight, causing dripping (drip), and the dripping adheres to the periphery of the application portion of the object for ejecting the ejection liquid or the periphery of the liquid ejection device. However, this may impair the external appearance of the target object, the liquid ejection device, or the like, or deteriorate their functions. Threading occurs between the discharged liquid discharged and the liquid remaining in the nozzle, and the yarn adheres to the periphery of the liquid discharging device, impairing the appearance and the surrounding environment. For this reason, it is necessary to cut the string, which is troublesome. If the discharged liquid remaining in the nozzle is left to stand, the residual liquid in the nozzle hardens and nozzle clogging occurs. Therefore, when the waiting time is long, it is necessary to manually clean the nozzle. Alternatively, the discharge liquid must be periodically discharged from the nozzle so that the residual liquid does not harden in the nozzle, which is not economical.

The present invention has been made in view of the above-mentioned drawbacks of the conventional examples, and an object of the present invention is to prevent the discharge liquid from remaining in the nozzle and to prevent liquid dripping and stringing. It is to provide a discharge device.

[0007]

A first liquid ejecting apparatus of the present invention comprises a liquid storage section for accumulating the ejected liquid, a nozzle for ejecting the ejected liquid, and a device for opening and closing the nozzle. It is characterized by comprising a device that pushes the discharge liquid in the liquid storage portion from the opened nozzle by making the piston stroke so as to penetrate through the nozzle to the tip of the nozzle.

Further, the second liquid ejecting apparatus of the present invention moves in a liquid storage part for accumulating the ejection liquid, a nozzle for ejecting the ejection liquid, and a pipe connecting the liquid storage part and the nozzle. And a device for discharging the residual discharge liquid in the nozzle by stroking the plunger so as to penetrate the nozzle to the nozzle tip. It has a feature.

[0009]

In any of the liquid ejecting apparatus of the present invention, the ejecting liquid is ejected from the nozzle, and at the same time, the remaining ejecting liquid is forcibly ejected from the nozzle by penetrating the piston or the plunger to the tip of the nozzle. It was done,
In the first liquid ejecting apparatus, after opening the nozzle,
The piston is stroked to discharge the discharge liquid in the liquid storage portion from the nozzle, and at the same time, the piston is penetrated through the nozzle to completely discharge the discharge liquid from the nozzle.
Further, in the second liquid ejecting apparatus, after the piston is moved to eject the required amount of the ejected liquid from the nozzle, the plunger is penetrated into the nozzle and the remaining ejected liquid is forcibly ejected from the nozzle. Discharge. If the residual discharge liquid discharged from the nozzle in this way is discharged onto the discharge liquid application portion of the target object, the discharge liquid can be used without waste and the surroundings of the target object and the liquid discharge device etc. are contaminated. Never.

Therefore, since the inside of the nozzle is empty when the discharge liquid is on standby, no liquid dripping or stringing from the nozzle occurs, and the appearance of the object or the liquid discharge device is impaired due to contamination by the discharge liquid. It is also possible to prevent those functions from being impaired. Moreover, since the inside of the nozzle becomes empty during standby, dripping and stringing can be prevented regardless of the viscosity of the discharge liquid or the nozzle diameter, and especially when the viscosity of the discharge liquid is low or the nozzle diameter is small. Even if it is large, it is possible to effectively prevent dripping and stringing.

Further, since the nozzle clogging due to the hardening of the remaining discharge liquid does not occur, the labor for cleaning the nozzle can be saved and the labor can be saved. Alternatively, unlike the conventional case, it is not necessary to discharge the discharged liquid periodically to prevent the residual discharged liquid from being cured, and the economical efficiency is improved. Moreover, since the discharge liquid does not remain, the discharge amount is stable.

[0012]

1 is a schematic sectional view of a liquid ejecting apparatus 1 according to an embodiment of the present invention. Reference numeral 2 denotes a liquid storage unit (syringe) that stores the discharge liquid 8, and a nozzle 3 is provided on the lower end surface of the liquid storage unit 2. In addition, a piston 4 that is vertically stroked centering on the nozzle 3 is provided in the liquid storage unit 2, and the piston 4 is vertically moved by a piston drive device 5 provided at the upper end of the liquid storage unit 2. The nozzle is driven out of the nozzle 3 when rising, and protrudes to the tip of the nozzle when descending. In addition, the side surface of the nozzle 3 is provided with the nozzle 3 from the side wall surface.
A stopper driving device 7 for moving the stopper 6 in and out is provided therein, and the nozzle 3 can be fully closed by protruding the stopper 6.

Next, the operation of the liquid ejecting apparatus 1 during liquid ejection will be described with reference to FIGS. In the liquid ejecting apparatus 1, during standby, as shown in FIG. 2A, the plug 6 projects into the nozzle 3 to fully close the nozzle 3 and the piston 4 reaches the position where it abuts on the plug 6. It is descending. When ejecting liquid, first the piston 4
Is raised until it comes out of the nozzle 3 [FIG. 2 (b)].
As a result, the discharge liquid 8 flows into the nozzle 3 above the stopper 6. Next, when the piston 4 is lowered to the upper end of the nozzle 3 [FIG. 2 (c)], a constant amount of the discharge liquid 8 is separated from the discharge liquid 8 in the liquid storage unit 2 between the piston 4 and the stopper 6, and the constant amount is maintained. A quantity of the discharge liquid 8 is measured. After this,
As shown in (d), the stopper 6 is driven by the stopper drive device 7 to be retracted from the nozzle 3, and the piston 4 is lowered by the piston drive device 5 to push down the discharge liquid 8 in the nozzle 3 as shown in FIG. 2 (e). As shown in FIG. 2F, the piston 4 is projected from the tip of the nozzle to completely discharge the discharge liquid 8 in the piston 4 onto the object 9. In this way, the discharge liquid 8 is applied to the target 9
Then, the piston 4 is raised and the stopper 6 is projected into the nozzle 3 to return to the standby state [FIG. 2 (g)].
Therefore, the discharge liquid 8 does not remain in the piston 4, and the measured discharge liquid 8 can be applied to the target object 9 completely, and the application amount is stabilized.

FIG. 3 is a schematic sectional view showing a liquid ejecting apparatus 11 according to another embodiment of the present invention. In this embodiment, the lower surface of the liquid storage unit 12 storing the discharge liquid 8 and the nozzle 13 are connected by a horizontally connected connecting pipe 14, and a piston 15 is delivered into the connecting pipe 14. Has been done. The piston 15 is connected to the connecting pipe 14 by a piston drive device 16 provided at the end opposite to the nozzle 13.
The inside is slidable, and the liquid supply port 17 on the bottom surface of the liquid storage unit 12 is opened and closed by the piston 15.

The nozzle 13 has a large diameter portion 13a and a small diameter portion 13b.
The connecting pipe 14 is connected to the large-diameter portion 13a so that the resistance when the discharge liquid 8 is sent from the connecting pipe 14 into the nozzle 13 by the piston 15 is reduced. A plunger 18 is arranged in the nozzle 13 so as to be centered on the nozzle 13. Plunger 18
Is composed of an outer plunger portion 18a having the same diameter as the large diameter portion 13a of the nozzle 13 and an inner plunger portion 18b having the same diameter as the small diameter portion 13b. The plunger driving device 19 provided on the nozzle 13 causes the outer plunger portion 18a to Section 18a
The inner plunger portion 18b can be individually driven. The plunger 18 can be stroked up and down, and when the outer plunger portion 18a is lowered to the maximum, the large diameter portion 1
In the state where the inside of 3a is closed by the outer plunger portion 18a and the inner plunger portion 18b is lowered to the maximum, the inner plunger portion 18b penetrates to the tip of the nozzle 13.

Next, the operation of the liquid ejecting apparatus 11 when ejecting the liquid will be described with reference to FIGS.
FIG. 4A shows a state in which the liquid ejecting apparatus 11 is in a standby state, the nozzle 13 is closed by the lowered plunger 18, and the piston 15 moves backward to retract the liquid storage unit 12.
The liquid supply port 17 is opened, and the discharge liquid 8 is held in the connecting pipe 14. When ejecting liquid,
As shown in FIG. 4 (b), when the plunger drive device 19 raises the plunger 18 to open the nozzle 13 and the piston drive device 16 pushes out the piston 15, the discharge liquid 8 is pushed out from the nozzle 13 (FIG. 4 (c)). ].
Further, the plunger 18 is pushed down so that the discharge liquid 8 in the large diameter portion 13a is pushed out from the nozzle 13 [FIG. 4 (d)], and the inner plunger portion 18b is projected from the outer plunger portion 18a so that the inner plunger portion 18b becomes the small diameter portion 13b. Of the nozzle 13 to completely discharge the discharge liquid 8 in the nozzle 13 and return to the standby state as shown in FIG.

The nozzle, piston, plunger, etc. may be coated with Teflon. By applying the Teflon coating, stringing and the like are less likely to occur.

[0018]

According to the present invention, the ejection liquid can be completely ejected from the nozzle by penetrating the nozzle with the piston or the plunger. Therefore, when the discharge liquid is on standby, the inside of the nozzle is empty, so that no liquid dripping or stringing from the nozzle occurs, and the appearance of the target object or the liquid discharge device is damaged due to contamination by the discharge liquid. It can be prevented that the function of is impaired. Moreover, since the inside of the nozzle becomes empty during standby, dripping and stringing can be prevented regardless of the viscosity of the discharge liquid or the nozzle diameter, and especially when the viscosity of the discharge liquid is low or the nozzle diameter is small. Even if it is large, it is possible to effectively prevent dripping and stringing.

Further, since the nozzle clogging due to the hardening of the remaining discharge liquid does not occur, the labor of cleaning the nozzle can be saved and the labor can be saved. Alternatively, unlike the conventional case, it is not necessary to discharge the discharged liquid periodically to prevent the residual discharged liquid from being cured, and the economical efficiency is improved. Moreover, since the discharge liquid does not remain, the discharge amount is stable.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a liquid ejection device according to an embodiment of the present invention.

2 (a) (b) (c) (d) (e) (f) (g)
FIG. 3 is a schematic sectional view for explaining the operation of the above.

FIG. 3 is a cross-sectional view showing a liquid ejection device according to another embodiment of the present invention.

4 (a), (b), (c), (d), and (e) are schematic cross-sectional views for explaining the operation of the same.

[Explanation of symbols]

 2 Liquid Storage Section 3 Nozzle 4 Piston 6 Plug 8 Discharge Liquid 12 Liquid Storage Section 13 Nozzle 14 Connecting Pipe 15 Piston 18 Plunger

Claims (2)

[Claims] 1. A liquid storage unit for storing discharge liquid, a nozzle for discharging this discharge liquid, a device for opening and closing the nozzle, and a piston stroked so as to penetrate the nozzle to the tip of the nozzle. A liquid ejecting apparatus comprising: a device for ejecting the ejected liquid in a liquid storage unit from an opened nozzle. 2. A liquid storage part for storing the discharge liquid, a nozzle for discharging the discharge liquid, and a pipe connecting the liquid storage part and the nozzle for moving a necessary amount of the discharge liquid from the liquid storage part. A liquid ejecting device comprising a piston for sending to the nozzle and a device for discharging the residual ejected liquid in the nozzle by making a stroke of the plunger so as to penetrate the nozzle to the tip of the nozzle.