JP2023089456A - Deaeration device and liquid discharge device - Google Patents

Abstract

To provide a deaeration device which liquefies a volatile solvent discharged during deaeration to recover the volatile solvent, and to provide a liquid discharge device.SOLUTION: A deaeration device 200 includes: deaeration means 201 disposed in a liquid path 121 extending from a liquid tank 110 to a head 100; decompression means 202 which decompresses the deaeration means 201; a recovery part 203 which is disposed between the deaeration means 201 and the decompression means 202 and captures a gas exhausted from the deaeration means 201; and cooling means 204 which cools the gas captured by the recovery part 203.SELECTED DRAWING: Figure 1

Description

The present invention relates to a degassing device and a device for discharging liquid.

Some apparatuses for discharging liquid are provided with a degassing device for removing dissolved gas contained in the liquid from the liquid under reduced pressure.

Conventionally, an ink tank that stores ink, an inkjet head that includes nozzles that eject ink, and a circulating flow that circulates the ink supplied from the ink tank and collected in the ink tank via the inkjet head. a liquid feeding section provided in the circulation flow path to flow ink into the circulation flow path; and a degassing module for removing dissolved gas in the ink. A negative pressure section that puts the air module into a negative pressure state, and a separator provided in the negative pressure channel, and a first on-off valve in the outlet channel for recovering the liquid stored in the separator, the separator, and the negative pressure section. There is known an ink jet recording apparatus that includes a second on-off valve in a negative pressure flow path that connects the two (Patent Document 1).

Japanese Patent No. 6683499

In the past, low-volatility solvents were often used in water-based inks used for printing, but recently, various solvents are used, and the number of solvents that volatilize under reduced pressure conditions is increasing. As a result, the volatile solvent is discharged as VOCs (volatile organic compounds) from the degassing unit and the exhaust path along with degassing, and the volatilized solvent condenses at unintended locations.

The present invention has been made in view of the above problems, and an object of the present invention is to liquefy and recover the volatile solvent that accompanies degassing.

In order to solve the above problems, the degassing device according to the present invention is
a degassing means arranged in a liquid path from the liquid container to the liquid discharging means;
depressurizing means for depressurizing the degassing means;
a collection unit disposed between the degassing means and the decompressing means for capturing gas exhausted from the degassing means;
and a cooling means for cooling the gas captured by the recovery unit.

According to the present invention, the volatile solvent associated with degassing can be liquefied and recovered.

1 is an explanatory diagram of an apparatus for ejecting liquid according to a first embodiment of the present invention; FIG. FIG. 6 is an explanatory diagram of a device for ejecting liquid according to a second embodiment of the present invention; FIG. 3 is a block explanatory diagram for explaining a part related to control of discharge processing of a liquefied solvent from a recovery section in the same embodiment; FIG. 4 is a flow chart for explaining a liquefied solvent discharge process in the same embodiment. FIG. 11 is an explanatory diagram of a device for ejecting liquid according to a third embodiment of the present invention; It is explanatory drawing of the deaeration apparatus which concerns on 4th Embodiment of this invention. It is explanatory drawing of the deaeration apparatus which concerns on 5th Embodiment of this invention. It is explanatory drawing of the deaeration apparatus which concerns on 6th Embodiment of this invention. It is explanatory drawing of the deaeration apparatus which concerns on 7th Embodiment of this invention. It is explanatory drawing of the deaeration apparatus which concerns on 8th Embodiment of this invention. It is explanatory drawing of the deaeration apparatus which concerns on 9th Embodiment of this invention. It is explanatory drawing of the deaeration apparatus based on 10th Embodiment of this invention. It is explanatory drawing of the deaeration apparatus based on 11th Embodiment of this invention. FIG. 20 is a schematic explanatory diagram of a device for ejecting liquid according to a twelfth embodiment of the present invention; It is a plane explanatory view of the part of the printing means of the same apparatus. FIG. 3 is a block explanatory diagram for explaining an outline of a control unit of the same embodiment;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. A first embodiment of the present invention will be described with reference to FIG. FIG. 1 is an explanatory diagram of an apparatus for ejecting liquid according to the embodiment.

A device 1 for ejecting liquid includes a head 100 which is a liquid ejecting means for ejecting a liquid 111 , a liquid tank 110 which is a liquid container for storing a liquid 111 such as ink to be supplied to the head 100 , and the liquid 111 . A liquid-sending pump 120 is provided as a liquid-sending means. The liquid tank 110 has an atmosphere open path 113 . The liquid feed pump 120 is arranged in a liquid path 121 as a supply path from the liquid tank 110 to the head 100 .

The device 1 for ejecting liquid includes a degassing device 200 according to the present invention for degassing the liquid 111 sent from the liquid tank 110 to the head 100 .

The degassing device 200 includes degassing means 201 , pressure reducing means 202 , recovery section 203 and cooling means 204 . The deaeration unit 201 and the recovery unit 203 are connected via a pressure reduction pipe 205, which is a pressure reduction route, and the recovery unit 203 and the pressure reduction unit 202 are connected through a pressure reduction pipe 206, which is a pressure reduction route.

The degassing means 201 is arranged in the liquid path 121 from the liquid tank 110 to the head 100 . The degassing means 201 has, for example, a gas-liquid separation membrane using a hollow fiber membrane inside. is degassed by moving the dissolved gas to the reduced pressure side.

The recovery unit 203 is a trap tank that is arranged between the degassing means 201 and the pressure reducing means 202 and captures the gas discharged from the degassing means 201 . The recovery unit 203 is a sealed container, and a drainage pipe 207 serving as a drainage path is connected to the bottom. The drainage pipe 207 is provided with a drainage valve 208 which is an on-off valve.

The cooling means 204 is a first cooling means 241 arranged at least partially inside the recovery section 203 . The first cooling means 241 cools the gas trapped inside the recovery section 203 . Examples of the first cooling means 241 include a heat exchanger using a refrigerant as a cooling source, a heat pump using a Peltier element, cooling by contact with a low-temperature substance such as liquid nitrogen, and a method utilizing heat absorption by heat of solution. One or more cooling means can be used in combination. In this embodiment, a heat exchanger and a Peltier element are used to reduce consumables of the device.

The first cooling means 241 may be configured to cool from a cooling source via a cooling member. In this case, since the gas in the recovery section 203 can be directly cooled by the first cooling means 241 , the cooling effect can be obtained regardless of the material of the recovery section 203 . In addition, by installing it in the central part of the collection part 203, etc., it can be made relatively small.

Next, the operation of this embodiment will be described.

First, the collecting part 203 of the degassing device 200 forms a sealed space by closing the drain valve 208 . In this state, when the pressure reducing means 202 is driven, the degassing means 201, the pressure reducing pipe 205, the recovery section 203, and the pressure reducing pipe 206 are reduced in pressure from the ambient pressure.

As a result, the liquid 111 is decompressed through a gas-liquid separation membrane such as a hollow fiber membrane in the degassing means 201, the gas dissolved in the liquid 111 is released outside the gas-liquid separation membrane, and the liquid 111 is released. Degassing reduces the dissolved gas in the liquid 111 .

Here, the gas degassed and exhausted by the degassing means 201 is trapped in the recovery section 203 through the decompression pipe 205 . At this time, the first cooling means 241 is driven to cool the liquid to a temperature below the liquid temperature, so that the volatile component of the solvent contained in the gas exhausted from the degassing means 201 and captured by the recovery unit 203 cools and condenses. It liquefies and becomes a liquefied solvent 112 as a recovered liquid.

Since the liquefied solvent 112 is accumulated in the recovery unit 203 , when the decompression device 200 is stopped, the liquid discharge valve 208 is opened to discharge and recover the liquid to the outside through the liquid discharge pipe 207 .

In this manner, the volatile solvent associated with degassing can be liquefied and recovered.

Instead of directly using the cooling source as the first cooling means 241 to cool the gas in the collection unit 203, the cooling component is cooled via an antifreeze liquid such as an ethylene glycol aqueous solution, and the collection unit 203 is cooled by the cooling component. It can also be cooled.

In this case, the number of parts increases as compared with the direct cooling structure, but since the shape of the cooling parts can be freely designed, the specific surface area can be increased, and the gas cooling efficiency can be improved. Also, the cooling efficiency can be enhanced by using a metal with high thermal conductivity such as copper or aluminum for the cooling parts. In addition, when there is a risk that the first cooling means 241 will corrode due to contact with the solvent, durability can be enhanced by using a corrosion-resistant material such as SUS or applying corrosion-resistant plating to the surface of the material by interposing cooling parts. be able to.

Next, a second embodiment of the invention will be described with reference to FIG. FIG. 2 is an explanatory diagram of a device for ejecting liquid according to the embodiment.

In this embodiment, in addition to the configuration of the first embodiment, the recovery unit 203 is provided with an atmosphere release passage 211 that opens the inside to the atmosphere, and an atmosphere release valve 212 that opens and closes the atmosphere release passage 211 . The recovery unit 203 is also provided with a liquid detection sensor 213 as liquid level detection means for detecting that the liquid level of the liquefied and stored liquefied solvent 112 has reached a predetermined level.

Further, in the decompression pipe 205 between the recovery unit 203 and the degassing means 201 , a shutoff valve 214 as an opening/closing valve for opening and closing the decompression pipe 205 is provided. A pressure sensor 215 for detecting the pressure on the part 203 side is arranged.

Next, the part related to the control of the process of discharging the liquefied solvent from the recovery unit in this embodiment will be described with reference to the block explanatory diagram of FIG.

The discharge control means 600 takes in the detection results of the liquid detection sensor 213 and the pressure sensor 215 , controls the driving of the decompression means 202 , and controls the opening and closing of the liquid discharge valve 208 , the atmospheric release valve 212 and the shutoff valve 214 .

Next, the discharge process of the liquefied solvent in this embodiment will be described with reference to the flowchart of FIG.

The discharge control means 600 executes this liquefied solvent discharge process every time a predetermined time elapses while the device 1 is in operation.

First, the detection result of the liquid detection sensor 213 is checked (step S1, hereinafter simply referred to as "S1"), and it is determined whether or not the liquid detection sensor 213 detects the liquefied solvent 112 (step S1). S2). In other words, it is determined whether or not a predetermined amount of liquefied solvent 112 is stored in the recovery unit 203 .

Here, when the liquid detection sensor 213 detects the liquefied solvent 112, the shut-off valve 214 is closed (S3), the atmosphere release valve 212 is closed (S4), and the operation of the pressure reducing means 202 is stopped (S5).

After that, the detection result of the pressure sensor 215 is checked (S6), and it is determined whether or not the inside of the decompression pipe 205 is at atmospheric pressure (S7).

Then, when the inside of the decompression pipe 205 is at atmospheric pressure, the liquid discharge valve 208 is opened and a predetermined time elapses is waited (S9). The predetermined time is a predetermined time required for the amount of liquefied solvent 112 detected by the liquid detection sensor 213 to be discharged from the drainage pipe 207 of the recovery unit 203 .

Then, when a predetermined time has passed after opening the drain valve 208, the detection result of the liquid detection sensor 213 is checked (S10) to determine whether or not the liquid detection sensor 213 detects the liquefied solvent 112. (S11).

Here, when the liquid detection sensor 213 does not detect the liquefied solvent 112, the drain valve 208 is closed (S12), and the atmosphere release valve 212 is closed (S13). Thereafter, the decompression means 202 is activated (S14), the detection result of the pressure sensor 215 is checked (S15), and it is determined whether or not the decompression pipe 205 has reached the operating pressure (predetermined decompression state) (S16).

Then, when the decompression pipe 205 reaches the operating pressure, the shut-off valve 214 is opened to decompress the degassing means 201, and the discharge process ends.

On the other hand, in step S11, when the liquid detection sensor 213 detects the liquefied solvent 112, an error is notified as an abnormal operation, and error processing is performed.

In this liquefied solvent discharge process, the activation interval can be arbitrarily set in consideration of the liquefied solvent accumulation speed and the volume of the recovery unit 203. , preferably between 1 minute and 1 day.

Thus, by providing the shutoff valve 214 in the decompression pipe 205 and the atmospheric release path 211 and atmospheric release valve 212 in the recovery unit 203, the isolation valve 214 is closed and the recovery unit 203 is opened by opening the atmospheric release valve 212. decompression can be released.

As a result, the liquefied solvent 112 discharged from the degassing means 201 accumulated in the recovery unit 203 can be discharged from the liquid discharge pipe 207 by opening the liquid discharge valve 208 provided in the liquid discharge pipe 207 . .

Then, after the liquefied solvent 112 is discharged, the atmospheric release valve 212 and the liquid discharge valve 208 are closed, and after the decompression means 202 is operated, the shutoff valve 214 is opened to recover the volatile solvent generated from the degassing means 201 again. can do.

In this manner, a series of liquid discharging operations can be performed even while the liquid discharging apparatus 1 is discharging, and the liquid discharging apparatus 1 can be operated without stopping for liquid discharging.

Further, by providing the liquid detection sensor 213 in the recovery unit 203, when the liquefied solvent 112 accumulated in the recovery unit 203 exceeds a predetermined amount, it is possible to prompt the user to discharge the waste liquid according to the liquid amount. .

Furthermore, by providing the pressure sensor 215 in the decompression pipe 205 or the recovery unit 203, the valve operations of the shutoff valve 214, the atmospheric release valve 212, and the drain valve 208 are controlled according to the detection result of each sensor 215. By doing so, the liquefied solvent 112 in the recovery unit 203 can be automatically discharged.

As a result, the liquid amount of the liquefied solvent 112 in the recovery unit 203 can be controlled to a certain amount or less, and the liquid accumulated in the decompression device 200 when the liquefied solvent 112 accumulates excessively in the recovery unit 203 flows out and the decompression device 200 can be prevented from breaking down.

Next, a third embodiment of the invention will be described with reference to FIG. FIG. 5 is an explanatory diagram of a device for ejecting liquid according to the embodiment.

In this embodiment, a flow-through head (circulation head) is used as the head 100 .

Then, the liquid 111 is supplied from the sub-tank 130 to the head 100 via the liquid path 121 on the supply side by the liquid sending means 120, and the liquid 111 recovered from the head 100 is returned to the sub-tank 130 via the liquid path 122 on the recovery side. there is While the liquid sending means 120 is being driven, the liquid 111 is supplied from the sub-tank 130 to the head 100 , and the liquid 111 that is not ejected is returned to the sub-tank 130 .

The sub-tank 130 is replenished with the liquid 111 from the liquid tank 110 by the liquid feeding means 140 through the liquid path 141 . The sub-tank 130 is provided with an atmosphere open path 133 . The sub-tank 130 is provided with stirring means 135 including stirring blades and a driving source for stirring the liquid 111 inside.

A discharge pipe 207 connected to the recovery unit 203 is connected to the sub-tank 130 , and the liquefied solvent 112 recovered in the recovery unit 203 is returned to the sub-tank 130 by opening the drain valve 208 .

Further, the decompression pipe 206 between the decompression means 202 and the recovery unit 203 is provided with a shutoff valve 216 as an on-off valve.

As a result, when the recovery unit 203 is opened to the atmosphere, it can be cut off from the decompression means 202 as well.

Next, a fourth embodiment of the invention will be described with reference to FIG. FIG. 6 is an explanatory diagram of the degassing device according to the same embodiment.

In this embodiment, in the configuration of the first embodiment, a shutoff valve 216 as an on-off valve is provided in the pressure reducing pipe 206 between the pressure reducing means 202 and the recovery unit 203, as in the third embodiment. I have.

As a result, when the recovery unit 203 is opened to the atmosphere, it can be cut off from the decompression means 202 as well.

Next, a fifth embodiment of the present invention will be described with reference to FIG. FIG. 7 is an explanatory diagram of the degassing device according to the same embodiment.

In this embodiment, the first cooling means 241 is arranged on the outer periphery of the recovery section 203 . The first cooling means 241 cools the gas inside the recovery section 203 by cooling the outer peripheral portion of the recovery section 203 . In this case, the collecting part 203 is preferably made of a material such as metal with high thermal conductivity.

In this manner, the first cooling means 241 is arranged at the outer peripheral portion of the recovery portion 203 and cools the inside from the outer peripheral portion of the recovery portion 203, whereby the entire recovery portion 203 can be cooled, and the contact area with the gas can be reduced. becomes wider and the cooling efficiency improves. In addition, by cooling the recovery unit 203 itself, it is possible to suppress the re-volatilization of the liquefied solvent.

Next, a sixth embodiment of the present invention will be described with reference to FIG. FIG. 8 is an explanatory diagram of the degassing device according to the same embodiment.

In this embodiment, the second cooling means 242 is provided as the cooling means 204 for cooling the gas trapped in the recovery section 203 through the decompression pipe 205 between the degassing means 201 and the recovery section 203 .

Thus, by providing the second cooling means 242 as the cooling means 204 for cooling in the path from the degassing means 201 to the recovery section 203, the path (pressure reducing pipe 205) is elongated compared to the recovery section 203, Cooling efficiency is excellent because it comes into contact with gas a lot (for a long time).

Next, a seventh embodiment of the present invention will be described with reference to FIG. FIG. 9 is an explanatory diagram of the degassing device according to the same embodiment.

In this embodiment, both the first cooling means 241 and the second cooling means 242 are used. Here, the second cooling means 242 performs preliminary cooling to such an extent that the decompression pipe 205 is not clogged with the liquefied solvent 112 liquefied by cooling. The first cooling means 241 performs main cooling of the gas trapped in the recovery section 203 .

That is, when the decompression pipe 205 is clogged with the liquefied solvent 112 liquefied by cooling, the suction resistance increases. Therefore, after pre-cooling by the second cooling means 242, by performing main cooling by the first cooling means 241, while suppressing the increase in the suction resistance, the cooling efficiency is increased, and the vapor can be recovered without causing condensation in the piping. It can be carried out.

Next, an eighth embodiment of the present invention will be described with reference to FIG. FIG. 10 is an explanatory diagram of the degassing device according to the same embodiment.

This embodiment includes a heat insulating member 250 that covers the outer peripheral portion of the collecting portion 203 in the fourth embodiment.

As a result, heat from the outside is blocked into the recovery unit 203 to increase the cooling efficiency, and at the same time, by blocking the recovery unit 203 from the air outside the device, condensation caused by the external air in the recovery unit 203 is prevented. can be suppressed.

Next, a ninth embodiment of the present invention will be described with reference to FIG. FIG. 11 is an explanatory diagram of the degassing device according to the same embodiment.

In this embodiment, a plurality of (here, two) recovery units 203A and 203B are connected in series to the degassing means 201 .

In other words, the degassing means 201 is connected to the recovery section 203A on the first stage via the decompression pipe 205 . The recovery section 203A in the first stage is connected to the recovery section 203B in the second stage via a pressure reducing pipe 219 . The second-stage recovery section 203B is connected to the decompression means 202 via the decompression pipe 206 .

The collection unit 203A is connected to the drainage pipe 207 via the drainage pipe 207a, and the recovery unit 203B is connected to the drainage pipe 207 via the drainage pipe 207b. Furthermore, the atmospheric release path 211 is connected to the decompression pipe 219 .

In this way, by configuring the recovery section 203 in multiple stages, it is possible to change the set temperatures of the first cooling means 241 of the recovery section 203A in the first stage and the first cooling means 241 of the recovery section 203 in the second stage. .

As a result, the solvent that could not be removed by the first recovery section 203A can be removed by the second recovery section 203B.

Also, in the case of a solvent that freezes like water, it may freeze after dew condensation on the first cooling means 241 depending on the cooling temperature, and may not be recovered as a liquid in the recovery unit 203 . At this time, weak cooling that does not cause freezing is insufficient to cool the gas, resulting in a decrease in solvent recovery efficiency.

Therefore, by providing the recovery unit 203 with multiple stages as in the present embodiment, the cooling of the first cooling means 241 on one side is weakened to dissolve the frozen solvent and recover it as the liquefied solvent 112 in the recovery unit 203. By repeating this operation between the two collection units 203, the freezing of the solvent vapor can be resolved.

Next, a tenth embodiment of the present invention will be described with reference to FIG. FIG. 12 is an explanatory diagram of the degassing device according to the same embodiment.

In this embodiment, a discharge section 233 is provided to which the drainage path 207 connected to the collection section 203 is connected. A drainage path 237 is connected to the discharge portion 233, and the drainage path 237 is provided with a drainage valve 238 as an on-off valve. Also, an air release passage 234 is connected to the discharge portion 233 , and an air release valve 235 is provided in the air release passage 234 .

With this configuration, the liquefied solvent 112 accumulated in the recovery unit 203 provided with the first cooling means 241 is transferred to the discharge unit 233, and the discharge unit 233 is separated from the degassing system by closing the drain valve 208. state.

Therefore, by opening the air release valve 235 of the air release path 234 of the discharge part 233 and opening the drainage valve 238, the decompression system from the degassing means 201 to the decompression means 202 is not opened, and the liquid (liquefied solvent) is discharged. 112) can be discharged.

Next, an eleventh embodiment of the present invention will be described with reference to FIG. FIG. 13 is an explanatory diagram of the degassing device according to the same embodiment.

In this embodiment, two collection units 203A and 203B are connected in parallel with the deaeration unit 201 between the deaeration unit 201 and the decompression unit 202 .

In other words, the collection unit 203A is connected to the degassing means 201 via the decompression pipe 205 and the decompression pipe 205a branched from the decompression pipe 205 . The collection unit 203A is connected to the decompression means 202 via a decompression pipe 206 and a decompression pipe 206a branched from the decompression pipe 206. As shown in FIG. A shutoff valve 214 is provided on the pressure reducing pipe 205a, and a shutoff valve 216 is provided on the pressure reducing pipe 206a.

A first cooling means 241 is provided in the collecting section 203A. A drainage pipe 207 is connected to the collection unit 203A, and the drainage pipe 207 is provided with a drainage valve 208 . An atmosphere release passage 211 and an atmosphere release passage 211a branched from the atmosphere release passage 211 are connected to the recovery unit 203A, and an atmosphere release valve 212 is provided in the atmosphere release passage 211a.

The collection unit 203B is connected to the degassing means 201 via a decompression pipe 205 and a decompression pipe 205b branched from the decompression pipe 205 . The collection unit 203B is connected to the decompression means 202 via a decompression pipe 206 and a decompression pipe 206b branched from the decompression pipe 206. As shown in FIG. A shutoff valve 214 is provided on the pressure reducing pipe 205b, and a shutoff valve 216 is provided on the pressure reducing pipe 206b.

A first cooling means 241 is provided in the recovery section 203B. A drainage pipe 207 is connected to the collection unit 203B, and a drainage valve 208 is provided in the drainage pipe 207 . An atmosphere open path 211 and an atmosphere open path 211b branched from the atmosphere open path 211 are connected to the recovery unit 203B, and an atmosphere open valve 212 is provided in the atmosphere open path 211b.

Since it is configured in this way, the recovery section 203A and the recovery section 203B can be individually temperature-controlled by the respective first cooling means 241 .

As a result, even when a solvent that freezes after dew condensation is used, the recovery unit 203A and the recovery unit 203 are alternately used, and for example, the recovery unit 203B is used until the recovery unit 203A is thawed. , can be discharged after the recovery unit 203A is thawed.

Also, for example, by closing shut-off valves 214 and 216 of decompression pipes 205a and 206a leading to recovery section 203A, only recovery section 203A can be separated from the decompression system. Similarly, by closing shut-off valves 214 and 216 of decompression pipes 205b and 206b leading to recovery section 203B, only recovery section 203B can be isolated from the decompression system.

As a result, the liquefied solvent 112 in the recovery section 203A or the recovery section 203B can be discharged without canceling the decompression system.

The degassing devices 200 of the above embodiments can be combined with each other.

Next, a twelfth embodiment of the present invention will be described with reference to FIGS. 14 and 15. FIG. FIG. 14 is a schematic explanatory diagram of a device for ejecting liquid according to the same embodiment, and FIG. 15 is a plan explanatory view of a printing means portion of the same device.

The device 1 for ejecting liquid is a printing device, and includes a loading means 10, a guiding/transporting means 30, a printing means 50, a drying means 70, a carrying out means 90, and the like.

The carrying-in unit 10 carries in a sheet material P such as continuous paper. The guide conveying means 30 guides and conveys the sheet material P carried in from the carry-in means 10 to the printing means 50 . The printing unit 50 performs printing by ejecting liquid onto the sheet material P to form an image or the like. The drying means 70 dries the sheet material P to which the liquid is applied by heating or the like. The carrying-out means 90 carries out the sheet material P. As shown in FIG.

The sheet material P is sent out from the main winding roller 11 of the carry-in means 10 , guided and carried by rollers of the carry-in means 10 , the guide/conveyance means 30 , the drying means 70 , and the carry-out means 90 . is taken up by

The sheet material P is transported facing the ejection unit 51 in the printing means 50 , and an image is formed by the liquid ejected from the ejection unit 51 .

In the ejection unit 51, for example, full-line head arrays 501 (501A to 501F) for six colors are arranged from the upstream side in the transport direction. The head array 501 is liquid ejection means. The head array 501A ejects black K liquid (ink), the head array 501B ejects cyan C liquid (ink), the head array 501C ejects magenta liquid (ink), and the head array 501D ejects yellow liquid (ink) onto the conveyed sheet material P. The head array 501E ejects white W liquid. The head array 501F ejects gold or silver liquid. Note that the types and number of colors are not limited to this.

A head array 501 has a plurality of heads 100 arranged in a staggered manner on a base member 502 . A head 100 has a nozzle surface 101 on which a plurality of nozzles 102 for ejecting liquid are arranged.

Next, an overview of the control unit of this embodiment will be described with reference to the block explanatory diagram of FIG. 16 .

A control unit 700 includes a CPU 701 that controls the entire apparatus, a ROM 702 that stores fixed data such as various programs including programs executed by the CPU 701, and a RAM 703 that temporarily stores image data and the like.

The control unit 700 includes a rewritable non-volatile memory NVRAM 704 for retaining data even while the power supply of the apparatus is cut off, various signal processing for image data, image processing such as rearrangement, and other controls. It has an ASIC 705 that processes input and output signals.

The control unit 700 includes host I/F 706 and I/O 707 for transmitting and receiving data to and from the host.

The control unit 700 includes a print control unit 711 including data transfer means, drive signal generation means, and bias voltage output means for driving and controlling each head 100 of the ejection unit 51, and a drive IC for driving each head 100. A head driver 710 is provided.

The control unit 700 includes a liquid feeding means 120 composed of a liquid feeding pump and a supply system control section 713 for driving and controlling a solenoid valve group 712 . The control unit 700 includes a suction pump 715 connected to a cap 714 that caps the nozzle surface of the head 100 and a maintenance system control unit 717 that drives and controls a group of electromagnetic valves 716 .

The control unit 700 includes a degassing control unit 720 that drives and controls the decompression means 202 of the degassing device 200 , the cooling means 204 including the cooling member 243 , and various electromagnetic valve groups 260 . The cooling means is either one of the first cooling means 241 and the second cooling means 242, or both.

The control unit 700 can input and process various sensor information through the I/O 707 . For example, the detection result (sensor information) of the pressure sensor 215, the liquid detection sensor 213 of the recovery unit 203, the degassing pressure sensor 271 provided in the degassing means 201, the cooling temperature sensor 272 detecting the temperature of the cooling means 204, and other Each sensor information of the sensor group 733 is acquired and processed. Then, the control unit 700 extracts information necessary for controlling the apparatus 1 from the acquired information, and uses the information for control by the print control unit 711, the supply system control unit 713, the maintenance system control unit 717, the degassing control unit 720, and the like. do.

An operation panel 740 is connected to the control unit 700 . The operation panel 740 includes an input section 741 for inputting various information, a display section 742 for displaying and outputting various information, and a speaker 743 for outputting various information by sound.

An outline of control by the control unit in this embodiment will be described.

When using the degassing device 200 according to the present invention, cooling by the cooling means 204 takes time. Therefore, the degassing control part 720 of the control part 700 activates the cooling means 204 of the degassing device 200 before activating the depressurizing means 202 so that the degassed steam can be cooled.

By keeping the cooling means 204 in a state where the gas can be cooled, the vapor degassed by the degassing means 201 is sent to the recovery part 203, and when it comes into contact with the first cooling means 241, for example, the solvent can be removed from the vapor. On the other hand, when the cooling means 204 is not in a state capable of cooling the gas, the solvent cannot be removed from the vapor, and the solvent is discharged as exhaust gas from the decompression means 202, or the solvent medium is deposited in the decompression means 202. become more likely.

In addition, the degassing device 200 is activated before sending the liquid toward the head 100 by the liquid sending means 120 . As a result, the liquid sent from the degassing means 201 to the head 100 can be newly degassed, and ejection abnormalities caused by dissolved gas in the liquid can be reduced. At this time, in order to perform sufficient degassing, the better the cooling is, the better the degassing efficiency is. Therefore, the cooling means 204 is activated before the liquid feeding means 120 starts feeding the liquid.

Furthermore, the cooling means 204 of the degassing device 200 can be driven intermittently while the liquid feeding means 120 is being driven.

As a result, when the cooling means 204 is the first cooling means 241, freezing of dew condensation adhering to the first cooling means 241 is suppressed, the solvent adhering to the first cooling means 241 as a solid is reduced, and the solvent is collected and discharged as a liquid. can.

In the present application, the “liquid” to be ejected is not particularly limited as long as it has a viscosity and surface tension that can be ejected from the head. It is preferable that More specifically, solvents such as water and organic solvents, colorants such as dyes and pigments, functional-imparting materials such as polymerizable compounds, resins, and surfactants, biocompatible materials such as DNA, amino acids, proteins, and calcium. , Edible materials such as natural pigments, etc., including solutions, suspensions, emulsions, etc. These are, for example, inkjet inks, surface treatment liquids, components of electronic elements and light emitting elements, and formation of electronic circuit resist patterns It can be used for applications such as liquids for liquids and material liquids for three-dimensional modeling.

The "liquid ejection head" includes a piezoelectric actuator (laminated piezoelectric element and thin film piezoelectric element), a thermal actuator using an electrothermal conversion element such as a heating resistor, a vibration plate, and a counter electrode as energy sources for ejecting liquid. It includes those using an electrostatic actuator made of.

The "apparatus for ejecting liquid" includes an apparatus for ejecting liquid by driving a liquid ejection head. Devices that eject liquid include not only devices that can eject liquid onto an object to which liquid can adhere, but also devices that eject liquid into air or liquid.

The "liquid ejecting device" can include means for feeding, transporting, and ejecting an object to which liquid can adhere, as well as a pre-processing device, a post-processing device, and the like.

For example, as a "device that ejects liquid", an image forming device that ejects ink to form an image on paper, and powder is formed in layers to form a three-dimensional object (three-dimensional object). There is a three-dimensional modeling apparatus (three-dimensional modeling apparatus) that ejects a modeling liquid onto a formed powder layer.

Further, the "apparatus for ejecting liquid" is not limited to one that visualizes significant images such as characters and figures with the ejected liquid. For example, it includes those that form patterns that have no meaning per se, and those that form three-dimensional images.

The above-mentioned "substance to which a liquid can adhere" means a substance to which a liquid can adhere at least temporarily, such as a substance to which a liquid adheres and adheres, a substance which adheres and permeates, and the like. Specific examples include media such as recording media such as paper, recording paper, recording paper, film, and cloth, electronic components such as electronic substrates and piezoelectric elements, powder layers (powder layers), organ models, and test cells. Yes, and unless otherwise specified, includes anything that has liquid on it.

The material of the above-mentioned "thing to which a liquid can adhere" may be paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics, etc., as long as the liquid can adhere even temporarily.

Further, the ``device for ejecting liquid'' includes a device in which a liquid ejection head and an object to which liquid can be adhered move relatively, but is not limited to this. Specific examples include a serial type apparatus in which the liquid ejection head is moved and a line type apparatus in which the liquid ejection head is not moved.

In addition, the "apparatus for ejecting liquid" also includes a treatment liquid coating device that ejects a treatment liquid onto a sheet of paper in order to apply the treatment liquid to the surface of the sheet for the purpose of modifying the surface of the sheet of paper, There is an injection granulator that granulates fine particles of the raw material by injecting a composition liquid in which raw materials are dispersed in a solution through a nozzle.

1 Printing device (a device that ejects liquid)
50 printing means 100 head 110 liquid tank 111 liquid 112 liquefied solvent 120 liquid sending pump (liquid sending means)
121 liquid path 200 degassing device 201 degassing means 202 pressure reducing means 203, 203A, 203B recovery section 204 cooling means 233 discharge section 241 first cooling means 242 second cooling means 600 discharge control means

Claims (14)

a degassing means arranged in a liquid path from the liquid container to the liquid discharging means;
depressurizing means for depressurizing the degassing means;
a collection unit disposed between the degassing means and the decompressing means for capturing gas exhausted from the degassing means;
and cooling means for cooling the gas trapped in the recovery section. 2. The degassing device according to claim 1, wherein said cooling means is means for cooling said gas trapped in said recovery section. 3. The cooling means comprises means for cooling the gas captured in the recovery section, and means for cooling the gas passing through a path from the degassing means to the recovery section. 1. The degassing device according to 1. 4. The degassing device according to claim 2, wherein at least a portion of the means for cooling the gas captured in the recovery section is arranged inside the recovery section. 4. The degassing device according to claim 2, wherein the means for cooling the gas captured in the recovery section is arranged on the outer peripheral portion of the recovery section. 6. The degassing device according to any one of claims 1 to 5, further comprising a heat insulating member surrounding said recovery section. 2. The degassing apparatus according to claim 1, wherein said cooling means is means for cooling said gas passing through a path from said degassing means to said recovery section. 8. The degassing device according to any one of claims 1 to 7, comprising a plurality of recovery units connected in series with the degassing means. 8. The degassing device according to any one of claims 1 to 7, comprising a plurality of recovery units connected in parallel to the degassing means. 10. The deaerator according to any one of claims 1 to 9, further comprising a discharge part for discharging the recovered liquid obtained by liquefying the gas from the recovery part. means for ejecting liquid;
a liquid container containing the liquid;
a liquid feeding means for feeding the liquid from the liquid container to a means for discharging the liquid;
A device for ejecting liquid, comprising: a degassing device according to any one of claims 1 to 10. 12. The device for discharging liquid according to claim 11, wherein the cooling means is driven before driving the depressurizing means of the degassing device. 13. The apparatus for ejecting liquid according to claim 11, wherein the cooling means of the degassing device is driven before driving the liquid feeding means. 14. The apparatus for ejecting liquid according to claim 11, wherein the cooling means of the degassing device is intermittently driven while the liquid feeding means is being driven.

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