JP2015074125A - Supply channel shut-off device and supply channel shut-off control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a supply channel shut-off device and a supply channel shut-off control method which can suppress pressure fluctuation of an ink jet head.SOLUTION: An ink jet record device 1A is configured so that an electromagnetic valve 4 is disposed on an ink supply tube connecting a pressure adjustment mechanism 3 and an ink jet head 5, and during acceleration and deceleration of the ink jet head 5 in reciprocating motion, the ink supply tube is closed by the electromagnetic valve 4, and when the ink jet head 5 is in an ink discharge state, the ink supply tube is opened.

Description

  More specifically, the present invention relates to an inkjet head that reciprocates and a mechanism that blocks an ink supply channel during acceleration / deceleration of the reciprocating movement of the inkjet head. The present invention relates to a supply flow path cutoff device and a supply flow path cutoff control method.

  The ink jet recording apparatus is configured to perform image formation by ejecting ink droplets from an ink jet head at a predetermined timing and landing them on the surface of a recording medium. Many of the ink jet recording apparatuses include a mechanism for reciprocating the ink jet head on the surface of the recording medium in a predetermined scanning direction, and are configured to eject ink droplets during the reciprocating movement. .

  When the inkjet head is configured to reciprocate in this way, the ink supply tube that connects the inkjet head and the ink supply tank that supplies ink to the inkjet head has a reciprocating movement within the ink supply tube. It is known that pressure waves are generated by the inertia of ink. When ink pressure waves reach the inkjet head, ink ejection is adversely affected.

  Therefore, an ink jet recording apparatus equipped with a mechanism that suppresses the influence of pressure waves accompanying this reciprocating movement is conventionally known.

  For example, FIG. 5 is a partial cross-sectional view of the ink jet recording apparatus described in Patent Document 1. FIG. 5 shows a pressure buffer 220 interposed between the ink jet head and the ink supply tube. The pressure buffer 220 includes a pressure buffer body 201, a pressure buffer film 202, and a pressure buffer body. 201, an ink reservoir 203 formed in a region surrounded by the pressure buffer film 202, an electromagnetic valve 209 disposed in an ink flow path upstream of the ink reservoir 203, and a pressure in the ink reservoir 203 are measured. Pressure sensor 208 (indicating ink flow 207). In the pressure buffer 220, when ink is ejected from the ink jet head and the pressure in the ink reservoir 203 decreases, the pressure sensor 208 senses this and opens the electromagnetic valve 209 (FIG. 5A). ). When the ink ejection from the ink jet head is stopped, the electromagnetic valve 209 is opened until the pressure returns to a constant pressure while measuring the pressure with the pressure sensor 208. When the pressure in the ink reservoir 203 is restored, the electromagnetic valve 209 is closed (FIG. 5B). The moment when the pressure wave becomes the largest during the reciprocating movement is during acceleration and deceleration with the ink supply tube fully extended, but in general, ink is not ejected during acceleration / deceleration. As described above, the ink flow path is communicated only when the ink jet head ejects ink, thereby reducing the influence of the pressure wave.

JP 2008-201077 A (published September 4, 2008)

  However, in the configuration of Patent Document 1 described above, the electromagnetic valve 209 is provided on the upstream side of the ink reservoir 203 of the pressure buffer 220. Therefore, when the pressure in the pressure buffer 220 fluctuates with the reciprocation of the ink jet head, there is a problem that the fluctuation is transmitted to the ink jet head.

  Therefore, the present invention has been made in view of the above-described problems, and an object of the present invention is to influence the pressure wave (pressure fluctuation) generated upstream of the ink jet head due to the reciprocation of the ink jet head on the ink jet head. An object of the present invention is to provide a supply flow path cutoff device and a supply flow path cutoff control method.

  In order to solve the above problems, a supply flow path blocking device according to the present invention includes an inkjet head that can reciprocate and an ink reservoir, and the pressure of the ink supplied to the inkjet head is controlled by the ink reservoir. A pressure adjusting mechanism that adjusts the ink storage section, and an ink supply channel that connects the ink reservoir and the inkjet head, and closes the ink supply channel at the time of acceleration / deceleration of the inkjet head that is reciprocating. A valve for opening the ink supply channel when in an ink ejection state is provided downstream of the ink reservoir in the ink channel direction.

  According to said structure, the valve which opens and closes an ink supply flow path is provided between the inkjet head and the pressure adjustment mechanism. Thereby, it is a case where the pressure in the pressure adjusting mechanism (specifically, in the ink reservoir) fluctuates with the reciprocation of the ink jet head, and the fluctuation is not transmitted to the ink jet head. Therefore, the ink pressure fluctuation in the ink jet head due to the reciprocating movement is effectively suppressed, the negative pressure control of the ink jet head can be performed optimally, the meniscus is not destroyed on the nozzle surface of the ink jet head, and the reliability is improved. High ink discharge can be realized.

  In addition to the above configuration, the supply flow path cutoff control device according to the present invention closes the ink supply flow path during acceleration / deceleration of the reciprocating ink jet head, and the ink is discharged when the ink jet head is in an ink ejection state. It is preferable to further include a control means for controlling the valve so as to open the supply flow path.

  According to said structure, a valve can be controlled by a control means and an ink supply flow path can be adjusted closing and open | release.

  In the supply flow path cutoff control device according to the present invention, in addition to the above configuration, the valve is preferably an electromagnetic valve that opens and closes the ink supply flow path by applying a voltage.

  According to the above configuration, it is possible to reliably and easily close and open the ink supply channel by using the electromagnetic valve.

  In addition to the above configuration, the supply flow path cutoff control device according to the present invention includes an ink supply section that supplies ink to the pressure adjustment mechanism, and an upper ink supply flow path that connects the ink supply section and the pressure adjustment mechanism. It is preferable that the upper ink supply flow path is bifurcated in the middle and has an annular shape.

  According to the above configuration, since the pressure fluctuation is canceled in the annular flow path by making the upper ink supply flow path annular, the pressure fluctuation of the inkjet head can be more effectively suppressed.

  In addition to the above configuration, the supply flow path cutoff control device according to the present invention preferably uses an electromagnetic valve whose pressure fluctuation during opening and closing is ± 5/100 atm or less.

  According to the above configuration, by using the electromagnetic valve having a relatively small pressure fluctuation, it is possible to optimally control the negative pressure of the inkjet head, and it is possible to realize more reliable ink ejection.

  In order to solve the above-described problems, a supply flow path cutoff control method according to the present invention includes an inkjet head that can reciprocate and an ink reservoir, and the pressure of the ink supplied to the inkjet head is controlled by the ink reservoir. A pressure adjusting mechanism that adjusts at the ink supply section, an ink supply channel that connects the ink reservoir and the inkjet head, and the ink supply channel that is provided downstream of the ink reservoir in the ink channel direction is closed. A supply flow path cutoff control method performed in a supply flow path cutoff device provided with a valve capable of controlling the valve so that the ink supply flow path is closed during acceleration / deceleration of the inkjet head during reciprocation. The valve is controlled so as to open the ink supply channel when the ink jet head is in an ink ejection state.

  According to said structure, the valve which opens and closes an ink supply flow path is provided between the inkjet head and the pressure adjustment mechanism. Thereby, it is a case where the pressure in the pressure adjusting mechanism (specifically, in the ink reservoir) fluctuates with the reciprocation of the ink jet head, and the fluctuation is not transmitted to the ink jet head. Therefore, the ink pressure fluctuation in the ink jet head due to the reciprocating movement is effectively suppressed, the negative pressure control of the ink jet head can be performed optimally, the meniscus is not destroyed on the nozzle surface of the ink jet head, and the reliability is improved. High ink discharge can be realized.

  According to the present invention, a supply flow path cutoff device and a supply flow path cutoff control method are provided in which pressure waves (pressure fluctuations) generated upstream of the inkjet head as the inkjet head reciprocates do not affect the inkjet head. be able to.

It is a figure showing one embodiment of a supply channel interception device concerning the present invention. It is the figure which showed the relationship between the pressure fluctuation of the inkjet head using a comparison structure, and the position of the said head. It is a figure which shows other embodiment of the supply flow-path interruption | blocking apparatus which concerns on this invention. It is the figure which showed the relationship between the pressure fluctuation of the inkjet head with which the inkjet recording device which is one Embodiment of the supply flow path interruption | blocking apparatus which concerns on this invention, and the position of the said head. It is a figure which shows a conventional structure.

Embodiment 1
Hereinafter, an embodiment of a supply flow path cutoff device and a supply flow path cutoff control method according to the present invention will be described with reference to FIG. In the present embodiment, description will be made based on an ink jet recording apparatus which is an example of a supply flow path blocking device according to the present invention.

  FIG. 1 is a diagram illustrating a configuration of an ink jet recording apparatus 1A (supply flow path blocking apparatus) according to the first embodiment.

  The ink jet recording apparatus 1A includes an ink cartridge 2 (ink supply unit), a pressure adjusting mechanism 3, an electromagnetic valve 4 (valve), and an ink jet head 5, and ink flows in this order. That is, the ink cartridge 2 is the most upstream of these, and the ink cartridge 2 and the pressure adjustment mechanism 3 are connected by the first ink supply tube 6a, and the pressure adjustment mechanism 3 and the inkjet head 5 are connected. An electromagnetic valve 4 is disposed in the ink supply tube. For convenience of explanation, the ink supply tube between the pressure adjustment mechanism 3 and the electromagnetic valve 4 is referred to as a second ink supply tube 6b, and the ink supply tube between the electromagnetic valve 4 and the inkjet head 5 is referred to as a third ink supply tube 6b. This is referred to as an ink supply tube 6c.

  The ink cartridge 2 is a conventionally known ink cartridge, and is installed in a cartridge holder (not shown) to supply ink to the pressure adjustment mechanism 3 via the first ink supply tube 6a.

  The pressure adjustment mechanism 3 has an ink storage part 3a, and the ink of the ink cartridge 2 is supplied from the first ink supply tube 6a to the ink storage part 3a and temporarily stored.

  Here, the first ink supply tube 6 a has a sufficient length so that the constituent members downstream of the ink cartridge 2 can reciprocate along with the reciprocation of the inkjet head 5.

  The pressure adjustment mechanism 3 adjusts the pressure of the ink in the ink reservoir 3 a so that the ink supplied to the inkjet head 5 is held at a predetermined pressure in the inkjet head 5. Specifically, in a state where ink is not ejected from the inkjet head 5 (non-ejection state), the pressure adjustment mechanism 3 keeps the ink in the inkjet head 5 at a negative pressure and prevents ink from leaking from the inkjet head 5. . On the other hand, in a state where ink is ejected from the inkjet head 5 (ejection state), pressure is applied so that the ink forms a meniscus in the inkjet head 5 and is ejected at a predetermined timing based on print data obtained from the outside. Is adjusted. The pressure adjustment by the pressure adjustment mechanism 3 can be realized by changing the volume of the ink storage portion 3a of the pressure adjustment mechanism 3. Note that the pressure adjustment method is not limited to this method.

  The electromagnetic valve 4 is located downstream of the pressure adjustment mechanism 3 in the ink supply direction, and closes the ink supply flow path (ink supply tube) between the pressure adjustment mechanism 3 (ink reservoir 3a) and the inkjet head 5. It is a valve that opens and closes. Although details will be described later, in the solenoid valve 4, the valve drive unit receives a signal from a control unit (not shown), and the valve drive unit applies a voltage to the solenoid valve 4 to control closing and opening.

  Here, as this control means, there is no limitation on the control method (supply flow path cutoff control method) as long as switching between closing and opening of the solenoid valve 4 as described later can be realized. For example, the position of the inkjet head 5 that reciprocally moves can be sensed by a position sensor (not shown), and a signal sent from the position sensor can be used as the control signal to switch between closing and opening the electromagnetic valve 4.

  In addition, grasp the timing chart of when the inkjet head 5 reaches the end of the reciprocating path after starting the reciprocating movement, and when and for how long it accelerates or decelerates. Therefore, based on this, the timing for closing the electromagnetic valve 4, the closing period, and the timing for opening the electromagnetic valve 4 are obtained in advance, and a control signal is sent to the valve drive unit in accordance with the timing. The voltage application timing to the solenoid valve 4 can also be controlled.

  As yet another aspect, the pressure fluctuation sensor is disposed in at least one place of the ink cartridge 2, the pressure adjustment mechanism 3, the ink jet head 5, or the ink supply tubes (first to third ink supply tubes 6a to 6c). When the pressure fluctuation is detected, a control signal is sent from the pressure fluctuation sensor to the valve drive unit, and voltage application to the electromagnetic valve 4 may be controlled.

  The inkjet head 5 is configured to reciprocate by a moving mechanism and guide means (not shown). For example, when a recording medium 10 (for example, paper or film) that is a landing target of ink droplets dropped from the inkjet head 5 is moved in the sub-scanning direction, the inkjet head 5 is moved in the main scanning direction perpendicular to the sub-scanning direction. , And by dropping ink droplets onto the surface of the recording medium at a predetermined timing during the movement, a desired image can be formed on the surface of the recording medium.

  Here, in the first embodiment, all the constituent members downstream of the ink cartridge 2 move together with the inkjet head 5 as the inkjet head 5 moves. Therefore, a pressure wave is generated due to the inertia of the ink in the ink supply tube as the reciprocating movement occurs. If the pressure wave of the ink reaches the ink jet head 5, the meniscus is destroyed, and if a positive pressure is applied, the ink is undesirably leaked from the ink discharge hole of the ink jet head 5, and if a negative pressure is applied, the ink discharge hole is reversed. As a result, ink is pulled up and air enters the head, which adversely affects ink ejection. Therefore, in the first embodiment, such an adverse effect is eliminated by the electromagnetic valve 4.

  In particular, in the first embodiment, the electromagnetic valve 4 is disposed between the pressure adjustment mechanism 3 (ink reservoir 3a) and the inkjet head 5 so that the pressure adjustment mechanism 3 (ink reservoir 3a) is within the position. The generated pressure fluctuation does not reach the ink of the ink jet head 5, and the ink jet recording apparatus 1 </ b> A capable of effectively suppressing ink pressure fluctuation in the ink jet head and realizing stable ink ejection can be provided.

  The results of comparing the effect of suppressing the pressure fluctuation of the ink in the ink jet head using the ink jet recording apparatus 1A of the first embodiment and the ink jet recording apparatus having a comparative configuration outside the scope of the present invention will be described later. Examples and comparative examples are shown. The difference between the comparative inkjet recording apparatus and the inkjet recording apparatus 1A of the first embodiment is that the comparative inkjet recording apparatus has neither a pressure adjustment mechanism nor an electromagnetic valve. That is, in the ink jet recording apparatus of the comparative configuration, the ink cartridge and the ink jet head are directly connected.

  As can be seen from the examples described later, according to the ink jet recording apparatus 1A of the first embodiment, the pressure fluctuation in the ink jet head 5 can be effectively suppressed as compared with the ink jet recording apparatus of the comparative configuration. I understand.

  The reason for the difference in effect between the two is due to the presence or absence of the pressure adjustment mechanism and the electromagnetic valve. That is, in the case of a comparatively configured ink jet recording apparatus, pressure fluctuation is caused in the ink jet head. On the other hand, according to the ink jet recording apparatus 1A of the first embodiment, not only the pressure adjusting mechanism 3 but also the electromagnetic valve 4 is arranged downstream of the pressure adjusting mechanism 3, so that the second The influence of the pressure wave of the ink in the ink supply tube 6 b and the influence of the pressure fluctuation generated in the pressure adjusting mechanism 3 (ink storage portion 3 a) are blocked upstream of the inkjet head 5 and reach the inkjet head 5. Can not be.

  Although not within the scope of the present invention, the pressure in the ink jet head is higher than that of the ink jet recording apparatus having the above-described comparative structure, even if only the solenoid valve 4 is removed from the ink jet recording apparatus 1A of the first embodiment. Variations can be suppressed. However, by disposing the electromagnetic valve 4 between the pressure adjustment mechanism 3 and the inkjet head 5 as in the first embodiment, the pressure fluctuation generated in the pressure adjustment mechanism 3 (ink storage unit 3a) can be reduced. It is possible not to reach 5. As shown in the examples described later, according to the configuration of the inkjet recording apparatus 1A of the first embodiment, the pressure fluctuation of the inkjet head 5 can be completely suppressed, and the configuration of the first embodiment is an advantageous configuration. I can say that.

  At the end of the first embodiment, the closing period and opening period of the electromagnetic valve 4 (control method of the electromagnetic valve 4) will be described. The electromagnetic valve 4 is closed during the acceleration / deceleration period of the inkjet head 5, but the closing period slightly extends before and after the acceleration / deceleration period. Here, the inkjet head 5 performs printing while moving at a constant speed, but during the constant speed period, a predetermined period immediately after entering the constant speed period from the acceleration period, and from the constant speed period to the deceleration period. Printing is not performed for a predetermined period immediately before the transition. Therefore, the electromagnetic valve 4 is closed during the period excluding the printing period. That is, a part of the period during which the electromagnetic valve 4 is closed includes a period during which the inkjet head 5 is moving at a constant speed.

  In this way, by extending the closing period of the solenoid valve 4 before and after the acceleration / deceleration period as well as the acceleration / deceleration period, pressure fluctuations generated upstream from the pressure adjustment mechanism 3 (ink storage unit 3a) and the pressure adjustment mechanism 3 occur. Further, the influence on the ink jet head 5 can be further suppressed.

[Modification]
In the first embodiment, the mode in which the electromagnetic valve 4 is provided in the middle of the tube arranged between the pressure adjusting mechanism 3 and the inkjet head 5 has been described. For this purpose, the position of the electromagnetic valve 4 may be at the ink supply port of the inkjet head 5. This modification is also included in the scope of the present invention.

  As a further modification, an electromagnetic valve 4 is provided at the ink supply port of the inkjet head 5, and is further disposed between the pressure adjustment mechanism 3 of the inkjet recording apparatus 1A of the first embodiment and the inkjet head 5. A configuration in which the pressure adjusting mechanism 3 and the ink jet head 5 provided with the electromagnetic valve 4 at the ink supply port are directly connected without using the ink supply tube is also possible. This modification is also included in the scope of the present invention.

[Embodiment 2]
A second embodiment of the supply flow path blocking device according to the present invention will be described with reference to FIG. Configurations other than those described in the second embodiment are the same as those in the first embodiment. For convenience of explanation, members having the same functions as those shown in the drawings in the first embodiment are given the same reference numerals, and explanation thereof is omitted.

  FIG. 3 is a diagram showing a configuration of an ink jet recording apparatus 1B which is an example of a second embodiment of the supply flow path blocking device according to the present invention.

  The difference between Embodiment 2 and Embodiment 1 is the shape of an ink supply tube (first ink supply tube 6a in Embodiment 1) disposed between the ink cartridge 2 and the pressure adjustment mechanism 3. .

  In the second embodiment, as shown in FIG. 3, the first ink supply tube 6 a ′ (upper ink supply flow path) disposed between the ink cartridge 2 and the pressure adjustment mechanism 3 branches in the middle. It is bifurcated and has an annular shape. Since the first ink supply tube 6a ′ is annular in this way, the pressure fluctuation is canceled in the annular flow path, so that the pressure fluctuation of the inkjet head 5 can be more effectively suppressed.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention.

[Additional Notes]
Inkjet recording apparatuses 1A and 1B according to an embodiment of the present invention include an inkjet head 5 that can reciprocate and an ink reservoir 3a, and the pressure of ink supplied to the inkjet head 5 is applied to the ink reservoir 3a. A pressure adjusting mechanism 3 to be adjusted; and an ink supply channel (second ink supply tube 6b and third ink supply tube 6c) that connects the ink reservoir 3a and the inkjet head 5; The ink supply channel (second ink supply tube 6b and third ink supply tube 6c) is closed during acceleration / deceleration of the inkjet head 5, while the ink supply channel (when the inkjet head is in an ink ejection state) ( Solenoid valve for opening the second ink supply tube 6b and the third ink supply tube 6c) It is provided on a downstream side of the ink flow path direction than the ink reservoir 3a.

  According to the above configuration, the electromagnetic valve 4 that opens and closes the ink supply flow path (the second ink supply tube 6b and the third ink supply tube 6c) between the inkjet head 5 and the pressure adjustment mechanism 3 is provided. I have. This is a case where the pressure in the pressure adjusting mechanism 3 (specifically, in the ink storage portion 3a) fluctuates with the reciprocation of the ink jet head 5, and the fluctuation is not transmitted to the ink jet head 5. Therefore, the pressure fluctuation of the ink in the ink-jet head 5 due to the reciprocating movement is effectively suppressed, the ink-jet head 5 can be optimally subjected to negative pressure control, and the meniscus is not destroyed on the nozzle surface of the ink-jet head 5, Highly reliable ink ejection can be realized.

  In addition to the above-described configuration, the ink jet recording apparatuses 1A and 1B according to an aspect of the present invention also include the ink supply channel (second ink supply tube 6b and The third ink supply tube 6c) is closed, and the ink supply flow path (second ink supply tube 6b and third ink supply tube 6c) is opened when the ink jet head is in the ink discharge state. 4 is further provided.

  According to the above configuration, the electromagnetic valve 4 can be controlled by the control means to adjust the closing and opening of the ink supply flow paths (second ink supply tube 6b and third ink supply tube 6c).

  In addition to the above configuration, the inkjet recording apparatuses 1A and 1B according to an embodiment of the present invention have a configuration in which the electromagnetic valve 4 opens and closes the ink supply channel by applying a voltage.

  According to the above configuration, by using the electromagnetic valve, it is possible to reliably and easily close and open the ink supply flow paths (second ink supply tube 6b and third ink supply tube 6c).

  In addition to the above configuration, the ink jet recording apparatus 1B according to an aspect of the present invention connects the ink cartridge 2 that supplies ink to the pressure adjustment mechanism 3, and the ink cartridge 2 and the pressure adjustment mechanism 3. The first ink supply tube 6a 'is further provided with a first ink supply tube 6a'.

  According to the above configuration, since the pressure fluctuation is canceled in the annular flow path by making the first ink supply tube 6a ′ annular, the pressure fluctuation of the inkjet head 5 is further effectively suppressed. be able to.

  Further, in the ink jet recording apparatuses 1A and 1B according to one embodiment of the present invention, the electromagnetic valve 4 has a pressure fluctuation of ± 5/100 atm or less during opening and closing.

  According to the above configuration, since the electromagnetic valve 4 has a relatively small pressure fluctuation, the inkjet head 5 can be optimally subjected to negative pressure control, and ink ejection with higher reliability can be realized.

  In order to solve the above-described problem, a supply flow path cutoff control method according to the present invention includes a reciprocating inkjet head 5 and an ink reservoir 3a, and controls the pressure of ink supplied to the inkjet head 5. A pressure adjusting mechanism 3 that adjusts in the ink reservoir 3a, an ink supply channel (second ink supply tube 6b and third ink supply tube 6c) that connects the ink reservoir 3a and the inkjet head 5, and And an electromagnetic valve 4 provided downstream of the ink reservoir 3a in the ink flow path direction and capable of closing the ink supply flow path (second ink supply tube 6b and third ink supply tube 6c). In the ink jet recording apparatuses 1A and 1B, the supply flow path shutoff control method The ink supply passage to control the solenoid valve 4 so as to be closed during deceleration, to control the solenoid valve 4 to open the ink supply channel when the ink-jet head 5 is in the ink discharge state.

  According to the above configuration, the electromagnetic valve 4 that opens and closes the ink supply flow path (the second ink supply tube 6b and the third ink supply tube 6c) between the inkjet head 5 and the pressure adjustment mechanism 3 is provided. I have. This is a case where the pressure in the pressure adjusting mechanism 3 (specifically, in the ink reservoir 3 a) fluctuates with the reciprocation of the ink jet head 5, and the fluctuation is not transmitted to the ink jet head 5. Therefore, the pressure fluctuation of the ink in the ink-jet head 5 due to the reciprocating movement is effectively suppressed, the ink-jet head 5 can be optimally subjected to negative pressure control, and the meniscus is not destroyed on the nozzle surface of the ink-jet head 5, Highly reliable ink ejection can be realized.

[Example 1]
The pressure fluctuation of the inkjet head 5 was confirmed using the inkjet recording apparatus 1A shown in FIG. The result is shown in FIG. FIG. 4 is a diagram illustrating the relationship between the pressure fluctuation in the inkjet head 5 and the position of the inkjet head 5.

  Referring to FIG. 4, when the inkjet head 5 reaches the leftmost end and the rightmost end and at a short period before and after that, a large pressure is applied to the inkjet head 5 during the closed period of the solenoid valve 4. It can be seen that there are no fluctuations.

[Comparative Example 1]
The ink jet recording apparatus having the above-described comparative configuration was used as the ink jet recording apparatus of this comparative example, and the pressure fluctuation in the ink jet head provided in the apparatus was confirmed. The result is shown in FIG. The ink jet recording apparatus of the comparative example does not have the pressure adjustment mechanism and the electromagnetic valve provided in the ink jet recording apparatus 1A of the first embodiment, and the ink jet recording has a configuration in which the ink cartridge and the ink jet head are directly connected. Device.

  FIG. 2 is a diagram showing the relationship between the pressure fluctuation in the ink jet head and the position of the ink jet head by the ink jet recording apparatus of the comparative example. In FIG. 2, the solid line indicates the pressure fluctuation in the inkjet head, and the broken line indicates the position of the inkjet head. The horizontal axis indicates time (seconds). The ink jet head was positioned at the leftmost end on the reciprocating movement path at the start of measurement, and reached the rightmost end after 1.5 seconds and then reciprocated back and forth to the leftmost after 1.5 seconds. In addition, acceleration and deceleration were performed before and after reaching the leftmost end and the rightmost end. On the other hand, the straight line portion between them indicates that the inkjet head is moving at a constant speed. As a result, as shown in FIG. 2, it was found that the pressure in the inkjet head fluctuated at the time when the inkjet head reached the leftmost end and the rightmost end and for a short period before and after. Specifically, it was found that a relatively large positive pressure was applied to the ink jet head before and after the ink jet head reached the leftmost end. On the other hand, it was found that a relatively large negative pressure was applied in the ink jet head at the time when the ink jet head reached the rightmost end and before and after that time. That is, it was found that the ink jet recording apparatus of the comparative example could not effectively suppress the pressure fluctuation in the ink jet head.

  In addition, it is necessary to comprise the solenoid valve used for this invention so that the meniscus in a nozzle may not be destroyed at the time of opening / closing operation | movement. For example, it is preferable to use an electromagnetic valve whose pressure fluctuation during opening and closing is ± 5/100 atm (about 5 KPa) or less.

  As described above, in the case of the ink jet recording apparatus of the comparative example, pressure fluctuation is generated in the ink jet head as the ink jet head reciprocates. On the other hand, according to the ink jet recording apparatus 1A of the example which is the configuration of the first embodiment, the electromagnetic valve 4 is disposed downstream of the pressure adjusting mechanism 3, and thereby the ink in the second ink supply tube 6b. Since the influence of the pressure wave and the influence of the pressure fluctuation generated in the pressure adjusting mechanism 3 (ink reservoir 3a) were blocked upstream of the inkjet head 5 and did not reach the inkjet head 5, the inkjet of the comparative example Compared with the recording apparatus 100, it was shown that the pressure fluctuation in the inkjet head 5 could be effectively suppressed.

  The present invention can be suitably used for an ink jet recording apparatus.

1A, 1B Inkjet recording device (supply channel blocking device)
2 Ink cartridge (ink supply unit)
DESCRIPTION OF SYMBOLS 3 Pressure adjustment mechanism 3a Ink storage part 4 Solenoid valve 5 Inkjet head 6a 1st ink supply tube 6a '1st ink supply tube (upper ink supply flow path)
6b Second ink supply tube 6c Third ink supply tube 10 Recording medium

Claims (6)

A reciprocating inkjet head;
A pressure adjusting mechanism that has an ink reservoir and adjusts the pressure of the ink supplied to the inkjet head in the ink reservoir;
An ink supply channel connecting the ink reservoir and the inkjet head;
The ink supply flow path is closed when the inkjet head is reciprocating during reciprocating movement, and a valve that opens the ink supply flow path when the inkjet head is in an ink ejection state is positioned in the direction of the ink flow path relative to the ink reservoir. The supply flow path cutoff device characterized by being provided downstream.   Control means is further provided for controlling the valve so as to close the ink supply channel when the inkjet head is reciprocating and accelerating / decelerating, and to open the ink supply channel when the inkjet head is in an ink ejection state. The supply flow path blocking device according to claim 1, wherein   3. The supply flow path cutoff device according to claim 1, wherein the valve is an electromagnetic valve that opens and closes the ink supply flow path by applying a voltage. An ink supply unit for supplying ink to the pressure adjustment mechanism;
An upper ink supply channel connecting the ink supply unit and the pressure adjustment mechanism;
4. The supply flow path interrupting device according to claim 1, wherein the upper ink supply flow path is divided into two portions in the middle and has an annular shape. 5.   4. The supply flow path interrupting device according to claim 3, wherein the electromagnetic valve has a pressure fluctuation of ± 5/100 atm or less during opening and closing. A reciprocating inkjet head;
A pressure adjusting mechanism that has an ink reservoir and adjusts the pressure of the ink supplied to the inkjet head in the ink reservoir;
An ink supply flow path connecting the ink reservoir and the inkjet head;
A supply flow path cutoff control method performed in a supply flow path cutoff device provided with a valve capable of closing the ink supply flow path provided downstream of the ink reservoir in the ink flow path direction,
The valve is controlled so that the ink supply channel is closed during acceleration / deceleration of the inkjet head during reciprocating movement, and the valve is controlled to open when the ink jet head is in an ink ejection state. Supply channel cutoff control method.

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