JPS5865670A - Clog preventing method for ink jet device - Google Patents

Abstract

PURPOSE:To reduce the consumption of ink by supplying ink for preventing clogging only to a thin layer of air. CONSTITUTION:As an ink jet device 1 returns to its home position, a valve 17 keeps a front chamber 8 opened to outside and pressurizes ink in an ink tank 11 and raises the pressure of ink in an ink chamber 4, and by the vibration of a piezoelectric vibrating plate ink equilibrium in No.1 orifice 7 collapses and ink 22 begins to flow out. Said ink 22 is maintained by capillary phenomenon acting on an air thin layer 8a and disperses in said air thin layer 8a. Under this condition, the flow out of ink from No.1 orifice 7 is stopped and the filling of ink to an air thin layer 8b is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for preventing clogging in an ink droplet ejecting device controlling the ltL section of an inkjet printer.

The biggest drawback of ink-ejecting devices is the orifice from which the ink droplets are ejected.
A rope m is being made.

Figure 1 and lI! Kaku presents a cross-sectional view to explain the method for preventing the present invention - which the applicant has already applied for a patent - (凰)
is an on-demand type ink droplet ejecting device, and the ink droplet ejecting device (1) includes: a pressure 11peng-* (2) that bends in response to the pressure, and the piezoelectric diaphragm (2). Placed in the mouth of II diameter with nine horn-shaped pressure wealth).

A thin plate-shaped vibrator (shu) freely attached to the short length of the pressure brocade (pressure brocade), an ink chamber (5) which is held interlocked with the Hm of the insulator (4), and the ink chamber ( 5) and the above l
I@ko (141 face plate (6) facing 43 and the front plate (6)
), the vibrator has a first orifice ()1 of minute diameter bored at a location opposite to the center of the 44DIIAW/II, and a thin air layer provided on the II11 side of the first orifice 4. (8a) and the air straightening layer (83).

The thin air layer (8) of the 11tJ7F is opened from the first orifice (7) through which the ink droplets (9) and - ejected from the first outlet r7J pass.
The second orifice is more than twice as large. @υ is the ink droplet ejecting device i! (This is an ink tank that supplies ink to the ink chamber (5) in No. 13, and several hundred cc of ink is stored in a bag made of polymer film or the like with low air permeability. (The ink supply pipe communicating with 53, σJ is an ink coupler placed in the middle of the ink supply pipe 0,
The ink supply pipe al extending from the intertank I to the ink coupler a3 can be attached freely, and ink can be replenished by replacing each ink tank I. Use a pump 1 to appropriately add air flow as shown by the arrow through the air supply pipe (151) to the fishing force (8) and the intertank (υ).

There is a thin air layer (8a) between the air pump basket and the thin air layer (8) in front of the ink droplet ejecting device (11).
The annular air rectifying layer (8 and the valve device 17, which is provided in the air supply pipe and consists of a three-way solenoid valve, for example), which rectifies the air flow σet# from the periphery, are arranged closely. There is. The valve unit vertical 1 is the air pump I during printing operation.
4 and a thin air layer (8) are placed in communication, and both of the above are set in a blocked state during non-printing and printing. Second orifice Ql
1 time with 9 recording media placed at a short distance in front of the
It is wound around a five-wheel drive shaft and is scanned in the main direction in one turn.

Figure 2 shows the ink droplet ejecting device (1) during Kishi printing operation.
This shows how the thin air layer (8) is filled with ink.

During the unloading process, the second office door is closed by a lid made of an elastic material such as rubber.

With the valve device αD cutting off the connection between the air pump No. 41 and the front chamber (8) J4 &' and opening the above-mentioned front chamber 1 (8), the air pump 1I4 is operated (ink tank 1).
When the ink inside the deaf is pressurized, the pressure of the ink inside the ink droplet ejector (ink chamber 15) also increases, and the first outlet ff)K)! ! - The ink that was in equilibrium at high pressure does not flow out from the ink seal (5) to the front wealth (8) due to the high pressure.

A piezoelectric diaphragm 12J is used to assist this ink flow.
When an electric signal is applied to the oscillator +4 to cause it to continuously vibrate in a curved manner for 1 kilometer, the flat blade of the ink immediately collapses and ink begins to flow from the 10th and 5th ice (73) to the wealth (81) in front.

Once the ink starts flowing out, even if you stop applying the electric signal to the piezoelectric diaphragm (phantom), the pressure (air pressure) in the front wealth (8) is lower than the ink pressure in the ink chamber (5), so the above ink flows out. The supply of ink continues. This first office σ" is supplied into the forward M(8) and is covered with ink. This supply of ink is detected by suitable detection means, e.g. It is controlled by detecting the resistance value between the body Q of 1) and the insulated air supply tube-inner cardiac effusion electrode (2).

When the ink rises in the air supply pipe and the detection electrode (2) is immersed, the resistance value of the body (2) and the detection electrode c111ml is drastically reduced by the ink, and the end of ink filling is detected.

If the vibration of the piezoelectric diaphragm (2) is continued until the filling is completed, the ink filling will be completed quickly or completely, so the method ξ is usually adopted. When it is detected that one chamber (8) has been filled with ink,
The operation of the air pump 114 is stopped and the pressure in the ink tank 1 gradually decreases. Meanwhile, ahead! (8J is the air supply pipe -
When the pressure in the ink tank decreases as described above in the state of sj, c in communication with the outside air through #1, ml (8)
K” is supplied and filled ink to inter tank 11Kw8?
To reverse flow, close the valve device -. During IP printing, the M-side chamber (8) and the air supply pipe system are in a closed state (1k), and the backflow of ink is prevented according to the so-called principle of L.

As a result, the ink droplet ejecting device (1) is in the non-printing operation, which is represented by (Iris T) in FIG.
! Since one of the first diapers ff1 (filled with millK ink) is filled with the ink, clogging caused mainly by drying and dust adhesion is prevented.

In this IIK table - Mposi V1 (IP) K, the front 1
! (8) Even though ink is supplied to the ink droplet ejecting device (1) and the first droplet jetting device (181) is prevented from occurring, the ink droplet ejecting device (1) is placed in a standby position VW (8 de) K#1l prior to the printing operation.
Opposed to LL gutter cjs. In this state, the valve device is 1m1
# Operate to communicate the air pump a4 with one chamber (8) and to control the air pump a4. Then, the ink filled in the front hole (8) is pressurized from the outer circumferential direction by the air flow a as shown by the arrow in FIG. It is discharged from the orifice. This discharged ink is captured by the opposing gutter I2υ. When the ejection operation is completed, the air flow 1G is stopped, the ink balance is maintained in the first orifice (71), and the ink droplet ejecting device (1) is in a standby state.

However, according to the method of refusing, the ink covering the first orifice (7) during non-printing operation is filled throughout the front chamber (8), so the standby positive V seal (sy)
The amount of ink that comes out of the KIA gutter C11' is amazing! It was said that this is the cause of the increase in ink consumption, which is approximately equal to the capacity of chuukata (8). For example, when the ink-jetting device (1) is operated continuously to form a solid black image on an A4 sheet, the amount of ink consumed is 11~
Although it is said to be about 12 cc and up to about 20 cc for normal printing of characters and figures, according to the above principle, at least more ink is used than is consumed for normal printing. Let it drain into the gutter (ha) v-@eh.

The present invention was made in view of the amount of ink discharged,
The method of the present invention will be explained in detail with reference to FIG. 5 onwards.

Figure 5 shows the state during non-printing operation in the present invention.
Ru. That is, one feature of the present invention is the filling of ink into the ink in front of the ink drop ejector port 1.

Conventional ink filling amount is '! ! (8) Filling the entire area - In case of one ejaculate tliK, the wealth in front (
8) Ink is supplied only to the thin air layer (a) and the ink that is originally filled in the front eiii (4) may clog the first orifice (7) during non-printing operations. Since the orifice (7) of the -1 is covered to prevent the ink from leaking, even the air rectifying layer (8-) located at the edge of the N18 on the ai side is filled with ink. In addition, the capacity of the above-mentioned air straightening layer CSB is such that the air from the thin air layer (-Todoroki) K air pump A4 is supplied by KIIEL, which can be rectified in both directions without disturbance. In order to add air flow, the capacity of the upper ε air thin layer (8) needs to be larger than that of 8. Therefore, it is not necessary to cover the first orifice (71) with ink. If you cut off the filling of ink into the air rectifying layer (8a) of the unnecessary large-capacity roller, the amount of ink required to cover the air thin layer (8a) will be limited to the storage hole (a) of the gutter 31. The amount of ink discharged is drastically reduced.

Figure 6 (AJ to (C)) shows the operation of supplying ink to the thin air layer (8a) according to the state. The second orifice is formed from a transparent plate with no holes in it.
- Immediately after returning to the home position (HP), it is empty - and the layer (8a) is filled with ink.

After that, open the front seal (8) to the outside by operating the lever device aη; in good condition, pressurize the ink in the ink tank (11) and increase the ink pressure of ink N (4) using the piezoelectric diaphragm ( 2), the equilibrium of the ink in the first orifice 17B collapses and the ink (2) flows out from the first orifice (7) as shown in Figure 6 (as shown in the phrase). , the ink (2) that has flowed out is held in the thin air layer (by capillary action acting on 89) and passes through the thin air layer (89).
8 as the "1st orifice (7) &'t" center, and a< is the empty-thin layer (as shown in CJ). It stops the ink from flowing out from the droplet (7) and prevents the filling of ink into the air conditioning layer (8b).Specifically, a hole is placed outside the thin air layer (8b) to prevent the filling of ink. By providing a conductive detection electrode (not shown), filling of ink only into the thin air layer (8 holes) is detected and the filling of ink into the thin air layer (8 holes) is stopped.

Another method is to apply ink (
2) The ink filling operation may be controlled at a predetermined time without the detection means Kli.
゛#1. Ink droplet ejection Vcllt f@- observed above
The specifications for (1) are listed below.

O 1st 157411) Opening diameter - 150 voice clear air thin layer (8 mm diameter 4$105w5w thickness t: 100 voice thin capacity": 7.85X10-"CC/air rectifying layer (8-) inner diameter &: 10g++m Outer diameter D!1sIIIm Depth t: t, 4awwa Capacity mah s 7N8510-” According to the ink droplet ejecting device (1) with the CC specification, the amount of ink to be filled in Ik is Mabata The nine that match 84XIO"CO in +mer are 7.85X1G-"CO and 17.

The ink discharged into the gutter Ql prior to printing can be suppressed to an extremely small amount as follows. Not things but 1. In short, the inter droplet (93&-first orifice (7) to be ejected) IIiJ7JK air thin layer (8
a) G.

The thin air layer (8-) is provided with an air rectifying layer (Ik).
7881! J steel air fan a- as disclosed in publications etc.
Any type of ink droplet ejecting device may be used.

From the above description, the present invention aims to prevent the ink from forming during the printing operation of the first orifice. Since the air flowing through the thin air layer does not fill the additional air straightening layer, the amount of discharge from the quinta prior to the printing operation is extremely small due to only the thin air layer, and the amount of ink consumed is suppressed. If ξ is achieved, it becomes possible to reduce the opening during filling in step #4.

[Brief explanation of the drawing]

1117th! l! Fig. 4 is a rounded cross-sectional view and sectional view for explaining the conventional example, sWJ is a cross-sectional view for explaining the method of the present invention, and Fig. 6 is a schematic diagram showing the method of the present invention by state. FIG. , Keichin-ink tank, 1
4...Air pump. -...Lid body. Figure 3 8 Figure 4

Claims (1)

[Claims] (1) a first orifice through which an ink droplet is ejected; and the first orifice i! a thin air layer that is provided in the irradiation force and is supplied with an air flow that assists the ejection operation of the ink droplets, an air rectifying layer that rectifies the air flow supplied to the thin air layer, and communicates with the thin air layer. and a second orifice through which the ink droplets ejected from the first orifice pass together with the air flow, the ink droplets being ejected from the first orifice into the thin air layer during non-printing operation. A method for preventing clogging in an ink droplet ejecting device, characterized in that ink is supplied only through the first orifice, and St 9C is applied to the first orifice.