JPH10291300A - Printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate leakage of liquid from a liquid passage, forward route coupling passage and reverse route coupling passage when releasing connection of forward route coupling passage connector and reverse route coupling passage connector of liquid to a liquid passage as part of a circulating route in a print head to a liquid passage side connector, in a liquid circulating system constituted to transfer liquid (cooling liquid) in contact with the head to regulate temperature of the head. SOLUTION: This printer comprises an atmosphere open solenoid valve 1058 and a return manifold 1056 provided at a position higher than a liquid level of the liquid stored in a cooling liquid storage tank 4100, a return manifold 1066 disposed at a position lower than the liquid level of the liquid F stored in the tank 4100. In this case, the circulating route is opened with the atmosphere at suitable timing prior to release of the connection, the liquid F is efficiently removed from all forward sub-tube, liquid tube 1040, and forward sub-tube 1062 and removed to the tank.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus, for example, a method in which a liquid such as ink is ejected from an ejection port, and the ejected droplets are adhered to a printing medium such as paper, cloth, nonwoven fabric, or back print paper to perform printing. Regarding the printing device to be performed,
For example, the present invention is suitable for application to an ink jet printing apparatus that continuously prints on a printing medium having a long width or a large width, such as a printing apparatus.

[0002]

2. Description of the Related Art Ink-jet printing apparatuses are widely used as printing units for printers, facsimile machines, copiers and the like because of their low running cost, quiet and high-speed printing, and the printing method is printing. Ink is ejected from a plurality of ink ejection ports formed in a head based on a print data signal, and the ink is attached to a print medium to perform printing.

In general, the viscosity of ink used in an ink jet printing apparatus changes with temperature. When the ink viscosity changes, the amount of ink ejected during the printing operation changes, and the dot diameter of the ink attached to the print medium changes. This change in dot diameter is not recognized by the human eye if the change in ink viscosity is small, so it is not substantially a problem. There is a problem that print density cannot be obtained. Further, when the dot diameter changes depending on the location on the same print medium, there is a problem that human eyes recognize it as so-called density unevenness. For this reason, controlling the temperature of the ink within a certain range (a range in which the density change cannot be recognized by human eyes) is desirable in order to achieve both print quality stabilization and cost reduction by simple temperature control. is there.

[0004] The method of controlling the temperature of the ink is substantially performed as the temperature control of the print head. As a factor of a change in the temperature of the print head, a change in the ambient temperature around the apparatus may be considered. ing. Rather, many of the factors of the printhead temperature change are the temperature rise due to the heat generated when the printhead is driven. For example, in the case of a serial printer, the amount of heat accumulated in the print head differs between the start of printing and the end of printing in one scan, so that the dot diameter differs near the print start portion and near the print end portion.

Generally, in a printer having a relatively narrow print width of a print medium such as a printer corresponding to an A4 size width or a printer having a relatively low print speed, a heater and a temperature detection sensor are provided in the print head, and the inside of the print head is provided. The variation of the dot diameter between the vicinity of the printing start portion and the vicinity of the printing end portion is recognized by the human eye only by optimizing the temperature of the print head by controlling the driving of the heater based on the signal of the temperature detection sensor. It can be suppressed to the extent that it cannot be done.

However, in a printer having a wide print width or a high print speed, the variation in the dot diameter between the vicinity of the printing start portion and the vicinity of the printing end portion is further increased. There is a problem that the variation in the diameter is recognized by the human eye as uneven density and the print quality is reduced.

As a measure for solving such a problem, there is a method of controlling the print head to be within a predetermined appropriate temperature range by bringing a specific liquid into contact with the print head.

Further, as a specific configuration example, a liquid such as water stored in a liquid storage portion such as a tank is circulated by a pump using a tube or the like as a liquid circulation path.
A configuration is conceivable in which the print head is brought into contact with a print path through a liquid passage provided in the middle of the liquid circulation path, and the liquid is returned to the liquid storage section again. In such a configuration, the liquid stored in the liquid storage unit is supplied by a pump and returned to the liquid storage unit again.

[0009]

In general, when an ink jet head is used for a long period of time, ink ejection becomes impossible due to defective foaming of ink, clogging in a liquid path due to scorching of ink, and breakage of a heater. May be. If the ink cannot be ejected even by the head function recovery process and the ink jet head is to be used for printing, a replacement operation of taking out the ink jet head from the apparatus main body and mounting a new ink jet head on the main body is performed.

In the above configuration, in order to replace the ink jet head, it is necessary to release the connection between the liquid passage and the liquid circulation path. However,
Since the liquid is filled in the liquid circulation path, it is natural that the liquid may leak if the connection of the liquid passage is released. There is a risk of degrading the quality. In addition, in consideration of scattering or outflow into the apparatus main body, it is necessary to add a special means for preventing the occurrence of unexpected inconvenience, for example, a means for preventing adhesion to an electric board.

An object of the present invention is to solve the above-mentioned problems and to effectively prevent liquid leakage when an ink jet head is replaced.

[0012]

For this purpose, the present invention provides:
In a printing apparatus that is detachable from the printing apparatus main body and performs printing using a print head having a liquid passage so that a liquid for temperature adjustment can flow in contact with the printing apparatus, a liquid storage unit that stores the liquid, A forward connection path for feeding the liquid from the liquid storage section to the liquid passage, a return connection path for returning the liquid from the liquid passage to the liquid storage section, and communication between the forward connection path and the liquid passage; A reversible connection, a return path connection that releasably connects the communication between the return path and the liquid path, the liquid storage section, the forward path, the liquid path and the liquid path. Circulating means capable of circulating the liquid between the return-path connecting paths, which is higher than the liquid level of the liquid stored in the liquid storage part in the middle of the circulating path. The location, the inside of said path, characterized in that a closing means for enabling air communication.

According to this configuration, the liquid can be removed from the liquid passage and the liquid circulation path by communicating the liquid circulation path with the atmosphere.
When the print head is replaced, the liquid does not leak even if the connection between the forward connection side connection part and the return connection side connection part and the liquid passage outward and return side connection part is released.

According to the present invention, there is provided a printing apparatus which performs printing by using a plurality of print heads which are detachable from a printing apparatus main body and have a liquid passage so that a liquid for temperature adjustment can flow in contact therewith. A liquid storage unit that stores the liquid, a forward connection path that feeds the liquid from the liquid storage unit toward the liquid passage, and the liquid path that is connected to the forward connection path and that is included in each of the plurality of print heads. Outgoing manifold for distributing the liquid, a plurality of outgoing sub-connecting paths respectively connecting the outgoing manifold and the plurality of liquid passages, and a plurality of outgoing sub-connecting passages and the plurality of liquid passages. A plurality of forward passage-side connecting portions for releasably connecting the communication, and a return manifold connected to the plurality of liquid passages for collecting the liquid A plurality of return path sub-connection paths respectively connecting the return path manifold and the plurality of liquid paths; and a plurality of connection paths for releasably connecting the plurality of return path sub-connection paths and the plurality of liquid paths. A return path connection section, a return path connecting path connecting the return path manifold and the liquid storage section, the liquid storage section, the forward path connection path,
A circulation means capable of circulating the liquid between the forward manifold, the plurality of forward return connection paths, the plurality of liquid passages, the plurality of return path sub-connection paths, the return path manifold and the return path connection path, Wherein the plurality of liquid passages are disposed above the liquid level of the liquid stored in the liquid storage portion, and one of the forward manifold and the return manifold is stored in the liquid storage portion. And the other is disposed below the liquid level of the liquid stored in the liquid storage section.

That is, in an apparatus for supplying the liquid to a plurality of print heads using a manifold,
It is possible to remove the liquid from the plurality of liquid passages and the liquid circulation path, and, similarly to the above, when the ink jet head is replaced, the connection state of the forward path side and return path side connection parts is released. The liquid does not leak.

In this embodiment, an opening / closing means is provided in the middle of the circulation path at a position higher than the liquid level of the liquid stored in the liquid storage section so that the inside of the path can communicate with the atmosphere. Can be provided.

In the above, when the print head is removed with the release of the communication between the outward connection portion and the return connection portion, the opening / closing means is allowed to communicate with the atmosphere, and then the operation for the removal is permitted. Control means can be provided.

Further, the opening / closing means may be an electromagnetic valve.

Further, the circulating means has a pump provided in the middle of the return path connecting path, and the control means causes the opening / closing means to communicate with the atmosphere when the pump is operating. The liquid can be sucked from inside.

Here, the pump can be a vortex pump.

Further, a backflow preventing means can be provided between the liquid passage and the pump in the middle of the return connection path, and the backflow preventing means can be an electromagnetic valve or a check valve.

Further, in the above, the print head may be in the form of an ink jet head for performing printing by discharging ink from a discharge port, and this ink jet head is used for discharging the ink. A heating element that generates heat energy that causes film boiling of ink as energy can be provided.

Further, as a form of the printing apparatus, an apparatus for performing printing on a cloth as a printing medium can be used.

[0024] In this specification, the term "print" means not only a case where significant information such as characters and figures are formed, but also a meaning which is significant or insignificant and which can be visually perceived by humans. Irrespective of whether or not the image is formed, a case where the image, the pattern, the pattern, and the like are widely formed by applying the liquid on the print medium, or the processing of the medium is also performed.

The "print medium" is not limited to paper used in a general recording apparatus, but also includes a wide range of cloth, plastic film, metal plate, etc., which can receive ink ejected by a head. Shall be.

Further, "ink" refers to the "print" described above.
Is a liquid that can be applied to a print medium to form an image, a pattern, a pattern, or the like, or to process the print medium.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings.

(First Example) FIGS. 1 and 2 are views showing an ink-jet printing apparatus according to an embodiment of the present invention. FIG. 1 is a main sectional view of the apparatus main body, and FIG. is there.

The ink jet textile printing apparatus shown in FIGS. 1 and 2 includes a printer section 100 for printing an image or the like on a print medium A such as a cloth, a transport section 200 for intermittently transporting the print medium A by a predetermined amount, and a roll-shaped print section. An unwinding unit 300 for unwinding the continuous print medium A, a drying unit 400 for drying the printed print medium A until it can be wound, and a winding unit 500 for winding the dried print medium A It consists of each part.

The print medium A is fed from the unwind roller 310
And the intermediate rollers 320 and 3
30 and is transported in the horizontal direction by a transport unit 200 provided at a position facing the printer unit 100.

The transport unit 200 includes a transport roller 210 provided on the transport path of the print medium A and provided upstream of the printer unit 100 and a belt drive roller 220 provided downstream of the printer unit 100. The endless conveyance belt 230 is wound between these rollers, and the print medium A is driven by a pair of platen rollers 240.
The transport belt 230 is regulated to be flat in a range to be a printing surface, and is stretched with an appropriate tension. An adhesive layer is provided on the outer peripheral surface of the transport belt 230, and the print medium A is attached and transported, and
The sheet is guided to a position opposite to 00, and printing is performed by the printer unit 100. Thereafter, the print medium A is peeled from the transport belt 230 by the feed roller 520, dried by the drying unit 400 including a heater or the like, and taken up by the winding roller 510 via the intermediate rollers 530 and 540.
Winded up by.

In FIG. 2, the printer unit 100 is provided with a pair of parallel scanning rails 101 and 102 in the main scanning direction orthogonal to the above-described transport direction of the print medium A. A head carriage 1100 on which the print head 1000 is mounted is slidably supported via a ball bearing 1110. The head carriage 1100 is driven by a drive motor (not shown) fixed to a frame of the printer unit 100 via a drive belt (not shown). The head carriage 1100 reciprocates on the scanning rails 101 and 102 in the directions of arrows P1 and P2 in the figure, and
000, the printing operation is performed on the continuous print medium A.

More specifically, for image data,
The data is distributed to the print head 1000 on the upstream side of the transport unit and the print head 1000 on the downstream side by 50%,
The whole image data is printed by both heads. That is, 50% of the image data is printed by the print head 1000 on the upstream side, and the remaining 50% of the image data is printed by the print head 1000 on the downstream side by intermittently feeding the print medium A. Print images formed by the respective print heads 1000 on the downstream side are superimposed.

FIG. 3 is a perspective view showing the internal structure of a print head 1000 and a liquid pipe 1040 which is a liquid passage mounted so that a cooling liquid F flows in contact with the print head 1000.

The print head 1000 includes a discharge port 1001 for fine ink, an ink path 1002,
Liquid chamber 100 that temporarily stores ink to be supplied to 002
3, an electrothermal conversion element 1004 provided in a part of the ink path 1002, and an electrode wiring 1005 for supplying electric power to the electrothermal conversion element 1004. A print head that uses such heat energy to generate bubbles in the ink and discharges the ink with the generation of the bubbles has a high resolution because the ink discharge ports can be arranged at a high density. It is suitable for printing. In addition, it is easy to make print heads more compact, and it is possible to make full use of the advantages of IC technology and micro-machining technology, which have recently achieved remarkable advances in technology in the semiconductor field and improved reliability, making it easy to achieve high-density mounting. Therefore, there are advantages such as a low manufacturing cost.

In the print head 1000, respective ink supply paths for feeding inks having different colors and densities from the ink supply device 2000 (see FIG. 2) to the liquid chamber 1003 inside the print head 1000, and a good ink discharge state. In order to control the temperature of the print head 1000 at an appropriate temperature, a liquid pipe 1040 for flowing the cooling liquid F is attached.

As shown in FIG. 2, the ink supply device 200
0 has, for example, eight ink tanks 2100a to 2100h corresponding to the ink colors to be used, and a supply pump for each ink tank, via an ink supply tube crawled inside the printer unit 100, Each ink is supplied to the corresponding print head 1000. In this ink supply system, ink is supplied according to ejection from the print head 1000 due to a capillary phenomenon during printing.

[0038] Each ink has the same color but different in color tone, such as dark ink and light ink, and is stored in each ink tank as separate ink. In this example, as described above, two print heads at the upstream and downstream correspond to one color ink. Accordingly, the head carriage 1100 has 8 printheads × 2 printheads / color = 16 printheads. That is, the same color ink is supplied to the upstream print head 1000 and the corresponding downstream print head 1000.

The recovery operation unit 3000 includes the print head 1
000 performs a recovery operation or the like for obtaining reliable ejection stability, and a capping unit 3 that covers the ejection opening surface of the print head 1000 to prevent an increase in ink viscosity.
100, a wiping unit (not shown) for wiping ink droplets or the like adhering to the discharge port surface of the print head 1000, and receiving an ink discharge for removing thickened ink generated in the print head 1000. A preliminary discharge unit (not shown), a cleaning liquid tank unit (not shown) for supplying a cleaning liquid, a pump unit (not shown) for sucking and discharging the waste liquid,
And a discharge unit (not shown) for receiving and discharging waste liquid discharged from the pump unit.

The coolant circulation device 4000 shown in FIG. 1 controls the coolant F in the coolant storage tank 4100 to a desired temperature, and the coolant pipe 1040 attached to the print head 1000 by the coolant feed pump 4200. To the cooling liquid storage tank 4100 again.

In FIG. 4, a coolant storage tank 4100
Inside, a not-shown cooler, a heater, and a temperature sensor are provided. The cooler is connected to an HFC-C through a compressor, a condenser, and a capillary tube (not shown) provided outside the coolant storage tank 4100. A refrigerant such as 134a is circulated. In the coolant storage tank 4100, a fixed amount of water or a dedicated coolant F is stored.

The coolant storage tank 4100 communicates with the atmosphere through an atmosphere communication hole 4101, and a tank outlet side connection port 4112 is provided on the bottom surface of the coolant storage tank 4100. The tank outlet side connection port 4112 is connected to a first outward main tube 1051a such as a spring hose which is not crushed by the action of negative pressure. The first outward main tube 1051a is connected to a T-shaped joint 1057, a strainer 1059, and a second outer tube. Outbound main tube 1051b
Through the outlet manifold 1056.
The outbound manifold 1056 has 16 outbound subtubes 1052 (1052-1F, 1052-1).
R,..., 1052-8R) are connected to each other, and the print head 1000
(1000-1F, 1000-1R, ..., 1000
-8R) is connected to the outward connection portion 1040a of the liquid pipe 1040. In addition, the homeward side 1 of the 16 liquid pipes 1040
040b via the return-side connector 1063 to the return-side subtube 1062 (1062-1F, 1062).
-1R,..., 1062-8R).

The outgoing-side subtube 1052, the returning-side subtube 1062, and the liquid pipe 1040 are connected to the outgoing-side connector 1053 and the outgoing-side connecting portion 104 of the liquid pipe 1040.
0a and the return-side connector 1063 and the return-side connection portion 1040b of the liquid pipe 1040 can be connected and disconnected, respectively, and the print head 100 as a consumable member.
When exchanging 0, these connections can be released and the print head 1000 can be exchanged.

The coolant F filled in the liquid tube 1040 and its vicinity can be collected in the coolant storage tank 4100 as described later. However, at least a part of the first outward main tube 1051a, 2 Outgoing main tube 1051b, liquid tube 1040, T-shaped joint 105
7. Strainer 1059 and outbound manifold 105
6 is a cooling liquid storage tank 41 when the cooling liquid F is collected.
The coolant F is disposed at a position higher than the liquid level of the coolant F stored in the fuel tank 00.

An atmosphere opening solenoid valve 1058, which is a normally closed type solenoid valve, is provided on a bypass of the T-shaped joint 1057.
The outward main tube 1051a and the second outward main tube 1051b communicate with the atmosphere.

The other end of the return tube 1062 is connected to the return manifold 1066. The return manifold 1066 is disposed at a position lower than the level of the coolant F stored in the coolant storage tank 4100 when the coolant F is filled in the coolant circulation path,
Via a return main tube 1061, a flow rate sensor 1067, and a backflow prevention solenoid valve 1068 which is a normally open type solenoid valve, it is connected to a suction side of a coolant supply pump 4200 which does not generate pulsation such as a vortex pump.
The outlet of the coolant supply pump 4200 is connected to a tank inlet side connection 4111 provided on a side surface of the coolant storage tank 4100.

A tank bypass connecting portion 4113 is provided on the bottom surface of the cooling liquid storage tank 4100, and communicates with a bypass suction port of the cooling liquid feed pump 4200 via a bypass tube 1070.

FIG. 5 is a block diagram showing a configuration example of a control system including such a coolant circulation system. Here, reference numeral 800 denotes a CPU serving as a main control unit of the control system, which controls each unit according to the processing procedures shown in FIGS. 803 is a CP
ROM storing a program and other fixed data corresponding to the processing procedure executed by U800, RAM 805 having an area for expanding print data and a required work area
It is.

811 is a heater provided in the coolant storage tank 4100, 813 is a compressor, 815 is a fan, 8
21, 823, 825, 827, 829, 831 and 833 are a heater 811, a compressor 813, a fan 815, a pump 4200, a solenoid valve 1058, and a solenoid valve 10, respectively.
68 and a driver for driving the print head 1000. Reference numeral 840 denotes a host device for executing a print operation, and 850 denotes a print head, which is denoted by P1, P in FIG.
A main scanning system including a mechanism for reciprocating scanning in two directions, 8
Reference numeral 60 denotes a sub-scanning system including a mechanism for conveying the print medium A. 870 is a coolant storage tank 4100
It is a temperature sensor provided inside.

Next, a method of controlling the temperature of the coolant F stored in the coolant storage tank 4100 will be described.

FIG. 6 shows an example of such a control procedure. In this example, the room temperature is 25 ° C., and the set temperature T of the cooling liquid F is (25 ± 0.5) ° C.

First, a signal for instructing the start of the cooling operation is given by CP
When U800 receives the signal, temperature sensor 870 notifies CPU 800 of the temperature of coolant F (step S1). Here, if the temperature of the cooling liquid F is lower than the lower limit of the set temperature of 24.5 ° C., the heater 811 is driven via the heater drive circuit 821 (step S3), and the temperature of F after cooling is lower than the lower limit of the set temperature of 24.5. When the temperature reaches ° C, the driving of the heater 811 is stopped. When the temperature of the cooling liquid F is lower than the lower limit of the set temperature 24.
If the temperature is higher than 5 ° C., the heater driving circuit 821
1 is not driven (step S5).

The temperature of the cooling liquid F is equal to the upper limit of the set temperature 25.5.
If the temperature is higher than ° C., the temperature sensor 870 notifies the CPU 800 to operate the compressor 813 and the air cooling fan 815 (step S7). The vaporized HFC-134a is heated to a high temperature and a high pressure by a compressor, and is fed in a refrigerant path.
The HFC-134a vaporized at a high temperature and a high pressure has a high boiling point and is easily liquefied, and is liquefied by being cooled by a forced air cooling fan (not shown) in a condenser. Liquefied HF
C-134a is depressurized by a capillary tube and fed to a cooler. HFC-1 liquefied fed to the cooler
Since 34a has a low pressure, it has a low boiling point and is easily vaporized, and takes heat from the cooling liquid F in contact with the cooler,
It is vaporized again and returned to the compressor. Due to such circulation of the refrigerant, the temperature of the coolant F from which heat has been taken decreases.

The temperature of the cooling liquid F is equal to the upper limit of the set temperature 25.5.
If the temperature is lower than ° C., the temperature sensor notifies the CPU 800 and stops the compressor 813 and the forced air cooling fan 815 (step S5). Thus, the compressor 813 stops supplying the refrigerant, and the forced air cooling fan 815 does not lower the temperature of the refrigerant in the condenser. Therefore, the refrigerant in the cooler remains vaporized, and the coolant F in contact with the cooler
Since the heat cannot be removed, the temperature of the cooling liquid F does not decrease.
Such a temperature control is repeated during the cooling operation.

Next, the coolant F whose temperature is controlled in this way is
A method for controlling the temperature of the print head 1000 by circulating the print head 1000 will be described.

FIG. 7 shows an example of the control procedure.
When the CPU 800 transmits a signal instructing the start of operation of the coolant supply pump 4200 (step S11), the coolant supply pump 4200 starts operating and the coolant storage tank 4
The suction of the cooling liquid F at the set temperature T stored in 100 starts. The coolant F stored in the coolant storage tank 4100 passes through the first outward main tube 1051a, T-shaped joint 1057, strainer 1059, second outward main tube 1051b, outward manifold 1056, and outward subtube 1052. The liquid is supplied to the liquid pipe 1040 of the print head 1000, and is supplied to the suction port of the coolant supply pump 4200 via the return sub tube 1062, the return manifold 1066, the return main tube 1061, the flow sensor 1067, and the backflow prevention electromagnetic valve 1068. enter. The coolant F that has entered the coolant supply pump 4200 flows from the outlet of the coolant supply pump 4200 through the tank inlet side connection port 4111 provided on the side surface of the coolant storage tank 4100 and the coolant storage tank. 4200.

After transmitting a signal instructing the start of operation of the coolant supply pump 4200, the CPU 800
067 (step S13), and if the flow rate is approximately a predetermined value within a predetermined time (step S15),
It is determined that the coolant F is filled in the coolant circulation path.

In this embodiment, the flow rate of the cooling liquid F passing through the liquid pipe 1040 is set at 600 ml / min.
The flow rate passing through No. 7 is 600 ml / min × 16 = 9.
Since it is 61 / min, 9.61 / min is set as the predetermined value of the flow rate detected by the flow rate sensor 1067.

The relationship between the filling rate of the coolant F in the coolant circulation path and the flow rate detected by the flow rate sensor 1067 is as follows.

If the operation of filling the cooling liquid circulation path with the cooling liquid F is not performed, the amount of the cooling liquid F passing through the flow rate sensor 1067 is small, almost gas, and the flow rate detected by the flow rate sensor 1067 is small. Is substantially “0”. As the filling rate increases, the flow rate sensor 1067
The detected flow rate gradually increases. If the filling rate rises to a state in which air (bubbles) is present in the cooling liquid F passing through the flow rate sensor 1067, the speed at which the bubbles pass is high. Is detected, and immediately thereafter, a flow rate larger than a predetermined value is detected. Next, if the filling rate further increases, the ratio of the bubbles in the cooling liquid F decreases, so that the flow rate detected by the flow rate sensor 1067 decreases. When the filling rate becomes almost 100%, the flow rate detected by the flow rate sensor 1067 becomes a predetermined value. At this time, since there is almost no bubble in the cooling liquid F, the flow rate detected by the flow rate sensor 1067 becomes the predetermined value. It is almost stable at. Therefore, the flow sensor 1
If the flow rate detected by 067 is stable at a substantially predetermined value within a certain period of time, it can be determined that the coolant F is almost filled in the coolant circulation path.

If the CPU 800 determines that the coolant F is almost completely filled in the coolant circulation path, the CPU 800 notifies the host 840 that the print head 1000 is ready for printing (step S17). Then, when a print start signal is sent from the host 840 and the image data is transferred, the print head 1000 starts driving.

The cooling liquid F supplied to the liquid pipe 1040 deprives the print head 1000 of heat and causes the return sub-tube 1
062, the return manifold 1066, the return main tube 1061, the flow sensor 1067, and the backflow prevention solenoid valve 1068, and enters the suction port of the coolant supply pump 4200. Coolant F in coolant feed pump 4200
Is discharged from the discharge port of the coolant supply pump 4200 into the coolant storage tank 4200 via a tank inlet side connection port 4111 provided on the side surface of the coolant storage tank 4100. Then, the operation of controlling the temperature to the set temperature T by the above-described temperature control and sucking the coolant again by the coolant supply pump 4200 is repeated.

Also, in this embodiment, a pump such as a pulsating pump having no pulsation is used as the cooling liquid feed pump 4200. Therefore, the flow rate of the cooling liquid F passing through the liquid pipe 1040 is always constant, and 1000 can be precisely controlled in temperature.

The first outward main tube 1051
a, T-joint 1057, strainer 1059, second outward main tube 1051b, outward manifold 1
056, the pressure of the cooling liquid F flowing through the outward sub-tube 1052, the liquid pipe 1040, and the return sub-tube 1062 is a negative pressure. Even if leaks to the atmosphere occur due to deterioration of materials or unexpected situations,
No leakage of the coolant F occurs, and the print medium A
It is possible to prevent the printed image from being contaminated due to the adhesion of the cooling liquid F to the print image.

Next, the procedure for replacing the print head 1000 will be described.

When the operator instructs a print head replacement mode by a key switch or the like when the print head 1000 needs to be replaced, the CPU 800
Performs an operation for recovering the cooling liquid F into the cooling liquid storage tank 4100 as described below.

[Coolant Recovery Mode] In the coolant recovery mode shown in FIG. 8, the CPU 800 first instructs the operation of the coolant supply pump 4200 (step S21). Then, the CPU 800 receives the signal from the flow rate sensor 1067 (step S23), and determines that the coolant F is filled in the coolant circulation path if the flow rate is substantially a predetermined value within a predetermined time. Here, the coolant F is provided in the coolant circulation path.
The reason for confirming that is filled is to ensure that a sufficient negative pressure is generated in the coolant circulation path when the air release solenoid valve 1058 is opened. In addition, other than the solenoid valve 1058, an air operated control valve and other various opening / closing means can be used as the valve for opening to the atmosphere. However, if the solenoid valve is used as in this example, the opening / closing operation is performed by an electric signal. It can be done only with on / off.

In step S23, the flow rate sensor 106
If it is determined that the detected flow rate is substantially equal to the predetermined value within the predetermined time, the CPU 800 drives a drive motor (not shown) of the main scanning system 850 to drive the head carriage 1 shown in FIG.
100 is moved to the home position above the recovery operation section 3000 shown in FIG. 2 (step S25). After confirming that the head carriage 1100 shown in FIG. 2 has moved to the home position, the CPU 800 instructs the air release solenoid valve 1058 to energize and opens the valve (step S27).

As described above, since the coolant F is filled in the coolant circulation path, the T-type joint 1057 between the opening of the air release solenoid valve 1058 and the tank outlet side connection port 4112, the strainer 1059 and the coolant F filled in the first outward main tube 1051a are:
The negative pressure due to the head difference caused by the opening of the atmosphere opening solenoid valve 1058 to communicate with the atmosphere causes the cooling fluid storage tank 4
100, the liquid level is lowered in the outward main tube 1051a, and is balanced by the liquid level of the cooling liquid F stored in the cooling liquid storage tank 4100.

The inside of the second outward main tube 1051 b, the outward manifold 1056, the outward subtube 1052, the liquid pipe 1040, and the return subtube 1062 between the opening of the air release solenoid valve 1058 and the tank inlet side connection port 4111. Similarly, the cooling fluid F filled in the return passage 1066, the return main tube 1061, the flow sensor 1067, and the backflow flow due to the negative pressure due to the head difference caused by the opening of the atmosphere opening solenoid valve 1058 and communication with the atmosphere. The liquid of the coolant F collected in the liquid storage tank 4100 via the prevention solenoid valve 1068 and the coolant supply pump 4200, the liquid level is lowered in the return tube 1062, and stored in the coolant storage tank 4100 Balance at surface height.

As in the present embodiment, the liquid pipe 1040, the air release solenoid valve 1058, and the outward manifold 1056 are connected to each other when the coolant F filled in the coolant circulation path is collected in the coolant storage tank 4100. Is disposed in a position higher than the liquid level of the cooling liquid F stored in the cooling liquid storage tank 4100 and communicates with the atmosphere through a circulation system by an atmosphere opening solenoid valve 1058 so as to be present in the liquid pipe 1040. Cooling fluid F, which has been removed, can be almost completely removed.
053 and the forward connection 1040a of the liquid pipe 1040, and the return connector 1063 and the return connection 1040b of the liquid pipe 1040 are released, regardless of the order of the release operation. Part 1040a
In addition, the coolant F does not overflow from the backward connection side 1040b.

On the other hand, if the air release solenoid valve 1058
If there is no, with the cooling liquid F filled,
Outgoing side connector 1053 and forward side connecting portion 1040a of liquid tube 1040, and backward side connector 1063 and liquid tube 104
When the zero return-side connecting portion 1040b is simultaneously released, the coolant F is instantaneously separated at this portion, and the coolant F remains in the liquid pipe 1040. Then, if the print head 1000 is tilted when the print head 1000 is replaced, the cooling liquid F overflows from the outward connection portion 1040a and the return connection portion 1040b of the liquid pipe 1040, and may leak or drip into the apparatus.

In this embodiment, the coolant supply pump 420
0, the opening of the solenoid valve 1058 is opened, so that the coolant F is further filled with the coolant F corresponding to the suction capacity of the coolant feed pump 4200.
0, the return subtube 1062
The liquid level inside is lower than the liquid level of the coolant F stored in the coolant storage tank 4100.

By these operations, the first outward main tube 1051a, the T-shaped joint 1057, the strainer 1059, and the second outward main tube 1051 are formed.
b, outbound manifold 1056, outbound subtube 10
52, liquid pipe 1040, and return subtube 1062
After a lapse of a predetermined time sufficient to collect the cooling liquid F filled in the inside (Step S29), the CPU 800 transmits a signal instructing the energization of the backflow prevention solenoid valve 1068 to close the valve (Step S31). Then, the operation of the coolant supply pump 4200 is stopped (step S33), and the coolant collection mode is ended. Further, the operator may be notified that the preparation for replacing the print head is ready with the end.

On the other hand, if the backflow prevention solenoid valve 1068 is
If the operation of the coolant supply pump 4200 is stopped without closing the pump, the following problem occurs. As described above, since the liquid level in the return path subtube 1062 is lower than the liquid level of the cooling liquid F stored in the cooling liquid storage tank 4100, the cooling liquid F flows backward due to the head difference. At this time, there is no problem as long as the cooling liquid F does not remain at all in the return path subtube 1062, but if the cooling liquid F remains at various places, the air between the scattered cooling liquid F Since there is air that is not communicated, the air that is not communicated with the outside air is pushed by the backflow of the coolant F,
Along with this, the cooling liquid F remaining in some places is also pushed and flows back into the liquid pipe 1040. As a result, the print head 10
At the time of replacement work of 00, leakage of the coolant F is likely to occur, and there is a possibility that the coolant F will scatter and flow into the inside of the apparatus.

If the operation of the coolant supply pump 4200 is stopped when the air release solenoid valve 1058 is opened, the level of the coolant F in the return subtube 1062 and the coolant storage tank 4100 Coolant F stored inside
Does not occur, the above-described backflow phenomenon of the cooling liquid F does not occur. However, in order to perform the operation of removing the coolant F from the inside of the liquid tube 1040 and the return path subtube 1062 earlier, the air release solenoid valve 1058 is opened during the operation of the coolant supply pump 4200 as in this example. Therefore, in this example, an electromagnetic valve 1068 as a means for preventing the backflow of the cooling liquid F as described above is provided and appropriately driven.

However, the backflow preventing means may be in a form other than the solenoid valve, for example, in the form of a check valve. When a check valve is used, electrical connection or the like is not required, and the configuration is accordingly simplified.

[Printhead Replacement Work] The printhead 1000 replacement work can be performed manually by an operator. At this time, as described above, since the coolant F can be collected before the print head 1000 is detached, when the print head 1000 is detached from the main body, the connection state of the outward path connector 1053 and the outward path connection portion 1040a of the liquid pipe 1040 is determined. Even when the connection state between the return-side connector 1063 and the return-side connection portion 1040b is released, the cooling liquid F drops or flows out from the forward-side connector 1053 and the return-side connector 1063, or the forward-side connection portion of the liquid pipe 1040. The coolant F does not overflow from the 1040a and the return-side connection portion 1040b, and the coolant F does not drop or leak into the apparatus.

After removing the used print head 1000, the operator mounts a new print head 1000 on the main body, and moves the forward connector 1053 and the liquid pipe 1040.
Outgoing side connection part 1040a and return path connector 106
3 can be connected to the return path connecting portion 1040b.

[Coolant Filling Mode] After the head replacement operation, air is present in the coolant circulation path. To perform the temperature control operation of the print head 1000 as described above, the cooling operation is performed. It is highly desirable to fill the liquid circulation path with the cooling liquid F to remove air from the cooling liquid circulation path.

The operation of filling the cooling liquid F will be described below.

In response to an operator's instruction or an instruction from the host 840, the CPU 800 sets the air release solenoid valve 1058
Is sent to close the cooling liquid circulation path substantially (step S41). Next, when the CPU 800 transmits a signal instructing the start of operation of the coolant supply pump 4200, the coolant supply pump 4200 starts operating (step S43), and is stored in the coolant storage tank 4100 from the bypass tube 1070. Inhale the cooling liquid F.

The coolant F stored in the coolant storage tank 4100 is supplied to the forward main tube 1051, the forward manifold 1056, the forward sub tube 1052, the liquid tube 1040 of the print head 1000, the backward sub tube 1062, and the backward manifold 1066. Through the suction port of the coolant supply pump 4200, but the ratio of air is large in the initial stage. However, since the coolant F is sucked from the bypass tube 1070, the coolant storage tank 4100 is
As compared with a configuration in which the pump is not connected to the cooling liquid feed pump 4200, the ratio of the cooling liquid F in the pump chamber is increased, and the pump capacity is not reduced. As the flow rate of the coolant F flowing through the bypass tube 1070 increases, the ratio of air in the pump chamber decreases, thereby improving the pumping capacity. On the other hand, the flow rate of the coolant supplied to the liquid pipe 1040 decreases.
It is desirable to set the inner diameter and length of the bypass tube 1070 and other tubes so that the filling time of the tube can be shortened and the flow rate flowing through the liquid tube 1040 can be both satisfied.

As described above, the operation of discharging the coolant F from the outlet of the coolant supply pump 4200 through the tank inlet side connection port 4111 provided on the side surface of the coolant storage tank 4100 is performed for a predetermined time. By continuing (step S45), the above-described coolant circulation path is filled with the coolant F. However, immediately after the coolant supply pump 4200 starts operating, air is discharged from the tank inlet side connection port 4111. Is done. Also, if the liquid level of the coolant F stored in the coolant storage tank 4100 is stored to a position higher than the tank inlet side connection port 4111, the air discharged from the tank inlet side connection port 4111 Is discharged into the coolant F stored in the coolant storage tank 4100 and becomes bubbles. Since the bubbles are generally lighter than the cooling liquid F, they rise in the stored cooling liquid F, are released from the liquid level to the atmosphere, and are removed from the above-described circulation path.

The ratio of air in the circulation path decreases as the operation time of the coolant supply pump 4200 elapses, and is completely removed from the circulation path after a predetermined time. This time
Outbound main tube 1051, outbound manifold 105
6, outbound subtube 1052, inbound subtube 10
62, the inner diameter and length of the return manifold 1066, the shape of the liquid pipe 1040, the coolant supply pump 4200
Although it depends on the capacity of the apparatus, it is almost constant for the same apparatus. Therefore, the predetermined time may be set with some allowance for the time obtained based on the experiment.

After the lapse of the predetermined time, the CPU 800 notifies the host 840 or the operator (in this case, for example, via an alarm) that the coolant F has been filled in the circulation path (step S47).

When the filling of the cooling liquid F into the cooling liquid circulation path is completed, the liquid level of the cooling liquid F stored in the cooling liquid storage tank 4100 becomes lower than before filling. The liquid level at the time is set to the connection port 4111 on the tank inlet side.
By setting at a higher position, the coolant F discharged from the tank inlet side connection port 4111 is discharged into the coolant F stored in the coolant storage tank 4100,
The level of the cooling liquid F is not disturbed.

Further, by providing the tank inlet side connection port 4111 on the side surface of the coolant storage tank 4100, there is a possibility that the air discharged from the tank inlet side connection port 4111 and the coolant F will be sucked in from the tank outlet side connection port 4112. Can be further reduced.

In this embodiment, an ink-jet printing apparatus has been described as an embodiment of the present invention. However, it is needless to say that any printing medium that performs printing on an ink-jet printing apparatus is effective. It is. That is, the print medium A is not limited to fabric, but may be paper or the like, and inks suitable for each print medium can be used.

As described in the first embodiment, the air release solenoid valve 1058 and the outward manifold 1056 are provided at a position higher than the level of the coolant stored in the coolant storage tank 4100, while the coolant storage tank is provided. 4100
By disposing the return manifold 1066 at a position lower than the liquid level of the coolant F stored therein and opening the atmosphere in the circulation path at an appropriate timing, all the outward subtubes 1052, the liquid pipes 1040, and the return path Sub tube 1
062, it is possible to remove the cooling liquid F more efficiently.

(Disposed Positions of Both Manifolds) Here, the present invention will be considered by paying attention to the disposed positions of the outward manifold 1056 which is a cooling liquid distribution member and the return manifold 1066 which is a cooling liquid collecting member.

As shown in FIG. 10, the coolant storage tank 4
The forward manifold 1056 and the backward manifold 106 are located at a position higher than the level of the coolant F stored in the inside 100.
In the case where both of them are arranged, the following problem may occur.

When the air release solenoid valve 1058 is opened,
The coolant F filled in the T-joint 1057, the strainer 1059, and the first outward main tube 1051a between the opening of the atmosphere opening solenoid valve 1058 and the tank outlet side connection port 4112 is opened by the atmosphere opening solenoid valve 1058. The liquid is collected in the coolant storage tank 4100 by a negative pressure caused by a head difference caused by communication with the atmosphere.

The second outward main tube 1051b, the outward manifold 1056, the outward sub-tube 1052, the liquid pipe 1040, and the return sub-tube 1062 between the opening of the air release electromagnetic valve 1058 and the tank inlet side connection port 4111. Similarly, the cooling fluid F filled in the air is supplied to the return manifold 1066, the return main tube 1061, the flow sensor 1067, and the backflow by the negative pressure due to the head difference caused by the opening of the atmosphere opening solenoid valve 1058 and the communication with the atmosphere. The coolant storage tank 4100 via the prevention solenoid valve 1068 and the coolant feed pump 4200
Collected inside.

At this time, the 16 outbound subtubes 152-1F to 152-1F-1 communicating with the outbound manifold 1056 are used.
052-8R, 16 liquid tubes 1040-1F to 1040-8R connected to each of them, and 16 liquid tubes connected to each of them (three in FIG. 5 for simplicity)
The cooling water F in the return sub-tubes 1062-1F to 1062-8R is gradually collected in the cooling liquid storage tank 4100. However, since the cooling liquid F has a surface tension, it is filled in each system. There is a slight time difference between the completion of the recovery of the cooling liquid F and the following reasons.

When the air opening solenoid valve 1058 is opened,
The liquid level of the coolant F in the second outward main tube 1051b starts to decrease due to the head difference. After the liquid level drops to the level of the forward manifold 1056, the forward manifold 1
056 communicates with the atmosphere from the connection portion with the second outward main tube 1051b. Since the coolant F has a surface tension, the outward sub-tube 105 closest to the connection portion is used.
2-1F, then the next closest outgoing sub-tube 1052-1R, etc., in order to communicate with the atmosphere, and finally the farthest outgoing sub-tube 1052-8R. Will communicate with the atmosphere. Also, each of the 16 outgoing sub-tubes 106
As soon as each of the cooling liquids F filled in the tank 2 communicates with the atmosphere, the outgoing sub-tube 1052 and the liquid pipe 1040
And, it is collected in the coolant storage tank 4100 via the return path subtube 1062.

At this time, if the pipe resistances are the same, the vicinity of the connection port of the return sub-tube 1062-1F first communicates with the atmosphere, the communication portion starts to expand, and the connection port with the return main tube 1061 starts. Nearby also communicates with the atmosphere. Then, the liquid level in the return manifold 1066 starts to decrease, but since the coolant F has a surface tension as described above,
In the vicinity of the connection port with the return path sub tube 1062-1R,
· Near the connection port with the return subtube 1062-8F;
Thus, the communication portion gradually widens, and finally, the return path subtube 1062-8R also communicates with the atmosphere.

At this time, for example, the return sub-tube 10
Before the vicinity of the connection port with the 62-8R communicates with the atmosphere, the inside of the outward sub-tube 1052-8R, the liquid pipe 1040-8R,
If the coolant F filled in the return path sub-tube 1062-8R is collected in the coolant storage tank 4100 and remains without ending, the liquid level of the coolant F stored in the coolant storage tank 4100 And the remaining coolant F remains in the liquid pipe 1040-8R and further in the outward subtube 1062-8R, and the outward connector 1053 and the outward connection port of the liquid pipe 1040. When the connection with the return-side connector 1063 and the connection between the return-side connector 1063 and the return-side connection port 1040b of the liquid pipe 1040 are released, the outward sub-tube 1062-8.
R and the return fluid from the return tube 1062-8R.
If the print head 1000-8R is tilted when the print head 1000-8R is removed, the coolant F leaks from the liquid pipe 1040-8R.

However, if the configuration and arrangement of the connecting portions between the respective manifolds and the subtubes are determined so as not to cause such a time difference, FIG.
It is also possible to arrange the forward manifold 1056 and the backward manifold 1066 at a position higher than the level of the coolant F stored in the coolant storage tank 4100 at such a position.

However, as in the above example, the return manifold 1066 is arranged at a position lower than the level of the coolant F stored in the coolant storage tank 4100,
Since the atmosphere is not communicated with the manifold disposed at a position lower than the liquid level of the cooling liquid F, an appropriate head difference can be reliably obtained, and all the outward sub-tubes 1052 and the liquid tubes 1
040, the coolant F can be removed from the return path subtube 1062, and there is no restriction on the design for preventing the above-mentioned time difference from occurring.

Also, from this viewpoint, the positional relationship between the forward manifold 1056 and the backward manifold 1066 can be reversed.

That is, in the above example, the forward manifold 1056 is arranged at a position higher than the level of the coolant F stored in the coolant storage tank 4100, and the return manifold 1066 is stored in the coolant storage tank 4100. Although arranged at a position lower than the liquid level of the coolant F, as shown in FIG. 11, the outward manifold 1056 is arranged at a position lower than the liquid level of the coolant F stored in the coolant storage tank 4100. , The return manifold 1066 is disposed at a position higher than the level of the coolant F stored in the coolant storage tank 4100, and the air release solenoid valve 1058 and the T-shaped joint 1 are disposed.
The same effect can be obtained if 057 is provided at a position higher than the level of the coolant F stored in the coolant storage tank 4100 in the middle of the return main tube 1061.

(Others) Next, in the case where the present invention is applied to an ink-jet printing apparatus, the entire printing process will be described. The fabric is dried (including natural drying) after the ink-jet printing step using the ink-jet recording apparatus to which the above-described embodiment is applied. Subsequently, a step of diffusing the dye on the fabric fiber and reacting and fixing the dye to the fiber is performed. By this process,
Sufficient color development and fastness due to fixing of the dye can be obtained.

The diffusion and reactive fixing steps may be performed by a conventionally known method, for example, a steaming method. In addition,
In this case, the fabric may be subjected to an alkali treatment before the printing step.

Thereafter, in the post-treatment step, the unreacted dye is removed and the substances used in the pre-treatment are removed.
Finally, the record is completed through an orderly finishing process such as defect correction and ironing.

In particular, as a fabric for ink-jet printing, (1) the ink can be colored to a sufficient concentration;
(2) high ink dyeing rate; (3) quick drying of the ink on the fabric; (4) less occurrence of irregular ink bleeding on the fabric; And high performance such as excellent transportability. In order to satisfy these required performances, in the present invention, the fabric can be subjected to a pretreatment beforehand, if necessary. For example, Japanese Patent Application Laid-Open No. 62-53492 discloses cloths having an ink receiving layer, and Japanese Patent Publication No. 3-46589 proposes a cloth containing a reduction inhibitor or an alkaline substance. I have. As an example of such a pretreatment, there can be mentioned a treatment in which a cloth contains a substance selected from an alkaline substance, a water-soluble polymer, a synthetic polymer, a water-soluble metal salt, urea and thiourea.

Examples of the alkaline substance include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide.
Examples thereof include amines such as mono-, di-, and triethanolamine, and alkali metal carbonates or bicarbonates such as sodium carbonate, potassium carbonate, and sodium bicarbonate. Furthermore, there are organic acid metal salts such as calcium acetate and barium acetate, ammonia and ammonia compounds. Further, sodium trichloroacetate which becomes an alkaline substance under steaming and dry heat may be used. Particularly preferred alkaline substances include sodium carbonate and sodium bicarbonate used for dyeing reactive dyes.

Examples of the water-soluble polymer include starch substances such as corn and wheat; cellulosic substances such as carboxymethylcellulose, methylcellulose and hydroxyethylcellulose; sodium alginate;
Locust bean gum, tragacanth gum, guar gum,
Examples include polysaccharides such as tamarind seeds, protein substances such as gelatin and casein, and natural water-soluble polymers such as tannin substances and lignin substances.

Examples of the synthetic polymer include a polyvinyl alcohol-based compound, a polyethylene oxide-based compound, an acrylic acid-based water-soluble polymer, and a maleic anhydride-based water-soluble polymer. Among them, polysaccharide polymers and cellulose polymers are preferable.

Examples of the water-soluble metal salts include compounds which form typical ionic crystals and have a pH of 4 to 10, such as halides of alkali metals and alkaline earth metals. Representative examples of such compounds include, for example, NaCl, Na ₂ S
O ₄ , KCl and CH ₃ COONa, and the like, and examples of the alkaline earth metal include CaCl ₂ and Mg
Cl _{2 and the} like. Among them, salts of Na, K and Ca are preferred.

[0111] The method of incorporating the above substances and the like into the fabric in the pretreatment is not particularly limited, and examples thereof include a commonly used dipping method, padding method, coating method and spraying method.

Further, since the printing ink applied to the ink-jet printing cloth simply adheres when applied to the cloth, it is necessary to carry out a fixing step of the dye or the like in the ink onto the fiber. Is preferred. Such a fixing step may be performed by a conventionally known method, for example, a steaming method, an HT steaming method, a thermofix method,
When a fabric which has been previously alkali-treated is not used, an alkali pad steam method, an alkali blotch steam method, an alkali shock method, an alkali cold fix method and the like can be mentioned. The fixing step may or may not include a reaction process depending on the dye. As an example of the latter, there is a method in which fibers are impregnated and do not physically separate. As the ink, any suitable ink can be used as long as it has a required pigment, and the ink is not limited to a dye and may include a pigment.

Further, the removal of unreacted dyes and the substances used in the pretreatment can be carried out by washing after the above-mentioned reaction fixing step according to a conventionally known method. In addition, it is preferable to use a conventional fixing process in combination with this cleaning.

The printed material which has been subjected to the post-processing steps described above is then cut into a desired size, and the cut pieces are subjected to a process for obtaining a final processed product such as sewing, bonding, welding and the like. Is applied to obtain clothes such as one-piece dresses, dresses, ties, and swimwear, duvet covers, sofa covers, handkerchiefs, curtains, and the like. A method of processing a fabric by sewing or the like to produce clothing or other daily necessities is a conventionally known technique.

Examples of the printing medium include textiles, wall cloths, threads used for embroidery, wallpaper, paper, OHP films, alumites and other plate-like materials, and various types of liquids to which a predetermined liquid can be applied using ink jet technology. The cloth includes all woven fabrics, non-woven fabrics and other fabrics regardless of the material, weave or knitting.

The present invention can employ not only the above-described ink jet printing method but also various printing methods. In the case where the ink jet printing method is used, among them, thermal energy is used as energy used for ink ejection. An excellent effect is provided by using a method of generating a change in the state of the ink by the thermal energy, that is, a bubble jet type print head and printing apparatus proposed by Canon Inc. This is because such a method can achieve higher density and higher definition of the print.

The typical configuration and principle are described in, for example, US Pat. Nos. 4,723,129 and 4,740.
It is preferable to use the basic principle disclosed in the specification of Japanese Patent No. 796. This method is a so-called on-demand type,
Although it can be applied to any type of continuous type, in particular, in the case of the on-demand type, it can be applied to a sheet holding liquid (ink) or an electrothermal converter arranged corresponding to the liquid path. Applying at least one drive signal corresponding to the printing information and providing a rapid temperature rise exceeding nucleate boiling, causing the electrothermal transducer to generate thermal energy, causing film boiling on the heat-acting surface of the printhead. This is effective because bubbles can be formed in the liquid (ink) corresponding to this drive signal on a one-to-one basis. The liquid (ink) is ejected through the ejection opening by the growth and contraction of the bubble to form at least one droplet. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubble are performed immediately and appropriately, so that the ejection of a liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable. As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. If the conditions described in U.S. Pat. No. 4,313,124 relating to the rate of temperature rise of the heat acting surface are adopted, more excellent printing can be performed.

The configuration of the print head is not limited to the combination of a discharge port, a liquid path, and an electrothermal converter (a linear liquid flow path or a right-angled liquid flow path) as disclosed in the above-mentioned specifications. A configuration using U.S. Pat. No. 4,558,333 or U.S. Pat. No. 4,459,600, which discloses a configuration in which a heat acting portion is arranged in a bending region, is also included in the present invention. In addition, for multiple electrothermal transducers,
JP-A-59-123670 which discloses a configuration in which a common slit is used as a discharge portion of an electrothermal transducer and JP-A-59-123670 which discloses a configuration in which an opening for absorbing a pressure wave of heat energy corresponds to a discharge portion. The effect of the present invention is effective even in a configuration based on JP-A-138461. That is, according to the present invention, printing can be performed reliably and efficiently regardless of the form of the print head.

In addition, it goes without saying that the print head can be configured in accordance with the form of the printing apparatus, and in the case of the so-called line printer form, the ejection openings are arranged in a range corresponding to the width of the print medium. What should be done. In addition, as a serial type print head as in the above example, a print head fixed to the apparatus main body, or an ink supply from the apparatus main body or an ink supply from the apparatus main body by being attached to the apparatus main body. The present invention is also effective when a replaceable chip-type printhead that can be used or a cartridge-type printhead in which an ink tank is provided integrally with the printhead itself is used.

It is preferable to add a print head ejection recovery means, a preliminary auxiliary means, and the like as the configuration of the printing apparatus of the present invention since the effects of the present invention can be further stabilized. If you list these specifically,
Pre-heating means for heating using a capping means, a cleaning means, a pressure or suction means, an electrothermal converter or another heating element or a combination thereof for the print head, Pre-discharge means for performing another discharge can be given.

In addition, in the embodiments of the present invention described above, the ink is described as a liquid. However, an ink which solidifies at room temperature or lower and which softens or liquefies at room temperature may be used. In general, the ink jet method generally controls the temperature of the ink itself within a range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in a stable ejection range. Sometimes, the ink may be in a liquid state. In addition, in order to positively prevent temperature rise due to thermal energy by using it as energy for changing the state of the ink from a solid state to a liquid state, or to prevent evaporation of the ink, the ink is solidified in a standing state and heated. May be used. In any case, the ink liquefies by the application of the heat energy according to the print signal,
The present invention is also applicable to a case in which an ink having a property of being liquefied for the first time by the application of thermal energy, such as an ink in which a liquid ink is ejected and an ink which starts solidifying when it reaches a print medium, is used. . In such a case, the ink is held in a state in which the ink is held as a liquid or a solid in the concave portion or through hole of the porous sheet as described in JP-A-54-56847 or JP-A-60-71260. Alternatively, it may be configured to face the electrothermal converter. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

In addition, as an embodiment of the present invention, in addition to the one used as an image output terminal of an information processing device such as a computer, a form of a copying apparatus combined with a reader or the like may be adopted.

[0123]

As is apparent from the above description, according to the present invention, there is provided a liquid circulation system configured to transfer liquid in contact with a print head in order to adjust the temperature of the print head. When the connection between the outward connection path side connection part and the return path connection path side connection part of the liquid to the liquid passage that is provided in the print head and forms a part of the circulation path, and when the liquid passage side connection part is disconnected, the liquid Since the liquid can be prevented from leaking from the passage, the outward connection path, and the return connection path, the liquid does not leak when the print head is replaced or the like, and the print medium is not likely to be stained, thereby improving the maintainability.

[Brief description of the drawings]

FIG. 1 is a side view showing a schematic configuration example of an inkjet printing apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view of the apparatus of FIG.

FIG. 3 is a perspective view showing an example of an internal configuration of a print head used in the apparatus of FIG.

FIG. 4 is a schematic diagram for explaining a configuration of a coolant circulation system and an operation of collecting the coolant in the apparatus of FIG. 1;

FIG. 5 is a block diagram showing a configuration example of a control system of the apparatus shown in FIG. 1;

FIG. 6 is a flowchart showing an example of a coolant temperature control procedure by the control system of FIG. 5;

FIG. 7 is a flowchart illustrating an example of a control procedure in a coolant circulation mode by the control system of FIG. 5;

FIG. 8 is a flowchart illustrating an example of a control procedure in a coolant recovery mode by the control system of FIG. 5;

FIG. 9 is a flowchart showing an example of a control procedure in a coolant filling mode by the control system of FIG. 5;

FIG. 10 is a schematic diagram for explaining a configuration of a coolant circulation system that may cause incomplete collection of coolant.

FIG. 11 is a schematic diagram for explaining another configuration example of the coolant circulation system.

[Explanation of symbols]

 1000 Print head 1040 Liquid tube 1040a Outgoing side connection port of liquid tube 1040 1040b Incoming side connection port of liquid tube 1040 1051 Outgoing main tube 1052 Outgoing sub tube 1053 Outgoing side connector 1056 Outgoing manifold 1058 Open air solenoid valve 1062 Incoming sub tube 1063 Incoming passage Side connector 1066 Return manifold 1068 Backflow prevention solenoid valve 4100 Coolant storage tank 4200 Coolant feed pump

Claims (13)

[Claims] 1. A printing apparatus which performs printing using a print head which is detachable from a printing apparatus main body and has a liquid passage so that a liquid for temperature adjustment can flow in contact therewith, wherein the liquid is stored. A liquid storage section, a forward connection path for feeding the liquid from the liquid storage section to the liquid passage, a return connection path for returning the liquid from the liquid passage to the liquid storage section, the forward connection path, An outward connection portion that releasably connects the communication with the liquid passage, a return connection portion that releasably connects the communication between the return connection passage and the liquid passage, the liquid storage portion, the outward connection passage, Circulating means capable of circulating the liquid between the liquid passage and the return connection path, and the liquid stored in the liquid storage portion in the middle of the circulating path. Higher than the liquid surface position, a printing apparatus, characterized in that a closing means for enabling air communicating the interior of said path. 2. A printing apparatus which performs printing using a plurality of print heads which are detachable from a printing apparatus main body and have a liquid passage so that a liquid for temperature adjustment can flow in contact therewith, wherein the liquid is stored. A liquid storage section, a forward connection path for feeding the liquid from the liquid storage section to the liquid passage, and the liquid passage connected to the forward connection path and provided in the liquid passages of the plurality of print heads. A forward manifold for distribution, a plurality of forward sub-connecting paths respectively connecting the forward manifold and the plurality of liquid passages, and a communication between the plurality of forward sub-connecting passages and the plurality of liquid passages, respectively; A plurality of outgoing-side connecting portions operably connected to each other; a return manifold connected to the plurality of liquid passages for collecting the liquid; A plurality of return path sub-connecting paths respectively connecting the fold and the plurality of liquid paths; and a plurality of return path-side connection sections for releasably connecting the plurality of return path sub-connection paths and the plurality of liquid paths. A return path connecting the return path manifold and the liquid storage section; and a liquid storage section, the forward path connection path, the forward path manifold, the plurality of forward path return connection paths, the plurality of liquid paths, and the plurality of liquid paths. Return sub-connection road,
Circulating means capable of circulating the liquid between the return path manifold and the return path connection path, wherein the plurality of liquid passages are above a liquid level of the liquid stored in the liquid storage section. And one of the outward manifold and the backward manifold is disposed above the liquid level of the liquid stored in the liquid storage part, and the other is stored in the liquid storage part. A printing apparatus, wherein the printing apparatus is disposed below the liquid surface of the printing apparatus. 3. In the middle of the circulation path, at a position higher than the liquid level of the liquid stored in the liquid storage section,
3. The printing apparatus according to claim 2, further comprising an opening / closing unit that allows the inside of the path to communicate with the atmosphere. 4. When the print head is removed with the release of the communication between the outgoing path side connection section and the return path side connection section, the opening / closing means is allowed to communicate with the atmosphere, and then the operation for the removal is permitted. 4. The printing apparatus according to claim 1, further comprising control means. 5. The printing apparatus according to claim 1, wherein said opening / closing means is a solenoid valve. 6. The circulation means has a pump provided in the middle of the return path connection path, and the control means causes the opening / closing means to communicate with the atmosphere when the pump is operating, and the circulation path The printing apparatus according to claim 4, wherein the liquid is sucked from the inside. 7. The printing apparatus according to claim 6, wherein the pump is a vortex pump. 8. The printing apparatus according to claim 6, wherein a backflow preventing means is provided between the liquid passage and the pump in the middle of the return connection path. 9. The printing apparatus according to claim 8, wherein said backflow prevention means is an electromagnetic valve. 10. The printing apparatus according to claim 8, wherein said backflow prevention means is a check valve. 11. The printing apparatus according to claim 1, wherein the print head has a form of an ink jet head that performs printing by discharging ink from a discharge port. 12. The printing apparatus according to claim 11, wherein the ink-jet head has a heating element for generating thermal energy for causing film boiling of the ink as energy for discharging the ink. 13. The printing apparatus according to claim 1, wherein printing is performed on a cloth as a print medium.