JP2021020451A - Liquid discharge device - Google Patents

Abstract

To efficiently cool a plurality of heat generation parts.SOLUTION: In a circulation passage 500 for temperature-regulation liquid 510, the liquid is pumped up from a temperature-regulation liquid tank 501 by a liquid feeding pump 502, distributed through a cooler 511 from a temperature-regulation liquid supply manifold 505 to heads 100, passed through temperature-regulation liquid passages 130 of the heads 100 to cool the heads 100, passed through the heads 100 to cool head driving parts (a head driving substrate 160 and a head driving IC 161), thereafter collected in a temperature-regulation liquid collection manifold 506, and returned to the temperature-regulation liquid tank 501. A frame member 120 of a head member 110, the head driving parts (the head driving substrate 160 and the head driving IC 161) in this order, i.e. in an ascending order of heat generation amount, when the cooler 511 is set as a starting point, are heat-connected to the circulation passage 500.SELECTED DRAWING: Figure 6

Description

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

In the head that discharges the liquid, a pressure generating means such as a piezoelectric element that discharges the liquid, a drive IC (driver IC) such as a switching circuit, and a power amplification unit that is arranged near the head to generate a drive waveform and drive the piezoelectric element. The liquid temperature rises as the temperature rises due to the heat generated by the heat-generating member such as the head drive substrate, and the discharge characteristics fluctuate.

Conventionally, a container for storing a temperature-adjusted temperature control liquid (cooling liquid) and a cooling means for cooling the cooling liquid of the container are provided, and the temperature control liquid from the container is distributed and supplied to a plurality of heads by an outward manifold. Then, it is known that the temperature control liquid is collected from a plurality of heads in the return path manifold and returned to the container (Patent Document 1).

Japanese Unexamined Patent Publication No. 10-86411

However, even with the configuration disclosed in Patent Document 1, there is a problem that a plurality of heat generating portions cannot be efficiently cooled.

The present invention has been made in view of the above problems, and an object of the present invention is to efficiently cool a plurality of heat generating portions.

In order to solve the above problems, the device for discharging the liquid according to the present invention is
A head that discharges liquid and
A circulation path through which the temperature-adjusted temperature control liquid circulates,
A cooling means for cooling the temperature control liquid is provided.
The circulation path is thermally coupled to at least two heat generating portions having different calorific values.
When the cooling means is used as the starting point, the two heat generating portions are thermally coupled to the circulation path in ascending order of heat generation amount.

According to the present invention, a plurality of heat generating portions can be efficiently cooled.

It is the schematic explanatory drawing of the printing apparatus as the apparatus which ejects the liquid which concerns on 1st Embodiment of this invention. It is a plane explanatory view of the head unit constituting the discharge unit of this apparatus seen from the nozzle surface side. It is sectional drawing in the short side direction (the direction orthogonal to the nozzle arrangement direction) of an example of a head. It is a plane explanatory view of the temperature control liquid flow path in line AA of FIG. It is a perspective explanatory view provided for the description of the ink and temperature control liquid port of the head. It is a block explanatory diagram provided for the explanation of the liquid (ink) supply system and the temperature control liquid circulation path system in the 1st Embodiment of this invention. It is a perspective explanatory view of the assembled state of an ink supply manifold and a temperature control liquid supply manifold. It is sectional drawing of the temperature control liquid supply manifold. It is a front sectional view which provides the detailed description of the temperature control liquid flow path of the same temperature control liquid recovery manifold. It is a perspective explanatory view of the connection part of the same temperature control liquid recovery manifold and a head drive substrate. It is also an exploded perspective explanatory view. It is a side view of the joint portion. It is explanatory drawing which provides the explanation of the positional relationship between a head, a temperature control liquid supply manifold, and a temperature control liquid recovery manifold. It is a block explanatory drawing which provides the explanation of the part which concerns the temperature control of a temperature control liquid. It is explanatory drawing of an example of the drive waveform for raising temperature control liquid. It is explanatory drawing of an example of the relationship between the duty (drive frequency) of the drive waveform for raising temperature of the same temperature control liquid, the environmental temperature and the temperature control liquid temperature. It is a block explanatory diagram provided for the explanation of the liquid (ink) supply system and the temperature control liquid circulation path system in the 2nd Embodiment of this invention. FIG. 5 is an exploded perspective explanatory view of a state in which the head and the cooling member are separated, which provides an example of a cooling member of a head having a head drive IC such as a waveform generation unit and a power amplification unit of a nozzle drive element in the head. It is a partial cross-sectional explanatory view of the direction orthogonal to the nozzle arrangement direction provided for the explanation of the temperature control liquid flow path of the cooling member. It is a partial cross-sectional explanatory view of the direction orthogonal to the nozzle arrangement direction provided to explain the thermal coupling between the cooling member and a head drive IC. It is explanatory drawing explaining the structure of the head unit and the circulation path of a temperature control liquid which concerns on 3rd Embodiment of this invention. It is also a perspective explanatory view provided for the explanation of the temperature control liquid circulation path of the dual head. It is a block explanatory drawing of the liquid (ink) supply system and the temperature control liquid circulation path system in 4th Embodiment of this invention. It is explanatory drawing which provides the explanation of the temperature control liquid circulation system in 5th Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. A printing device as a device for discharging a liquid according to the first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic explanatory view of the printing apparatus.

The printing device 1 includes a carry-in section 10 for carrying in the sheet material P, a pretreatment section 20, a printing section 30, a drying section 40, a carry-out section 50, and a reversing mechanism section 60. In the printing apparatus 1, the pretreatment unit 20, which is a pretreatment means, applies (coats) a pretreatment liquid to the sheet material P, which is carried (supplied) from the carry-in unit 10, as needed, and the printing unit 30 applies (coats) a liquid. Is applied to perform the required printing, the liquid adhering to the sheet material P is dried by the drying unit 40, and then the sheet material P is discharged to the carry-out unit 50.

The carry-in unit 10 separates the carry-in tray 11 (lower carry-in tray 11A, upper carry-in tray 11B) for accommodating a plurality of sheet materials P and the sheet material P from the carry-in tray 11 and sends them out one by one (12A). , 12B), and the sheet material P is supplied to the pretreatment section 20.

The pretreatment section 20 includes, for example, a coating section 21 which is a treatment liquid applying means for aggregating the color material of the ink and applying a treatment liquid having an effect of preventing show-through to the printed surface of the sheet material P. ..

The printing unit 30 includes a drum 31 which is a supporting member (rotating body) that supports the sheet material P on the peripheral surface and rotates, and a liquid discharge unit 32 that discharges a liquid toward the sheet material P supported on the drum 31. I have.

Further, the printing unit 30 receives the sheet material P sent from the pretreatment unit 20 and passes the sheet material P to and from the drum 31, and receives and dries the sheet material P conveyed by the drum 31. The delivery drum 35 to be handed over to the unit 40 is provided.

The tip of the sheet material P transported from the pretreatment unit 20 to the printing unit 30 is gripped by a gripping means (sheet gripper) provided on the transfer cylinder 34, and is conveyed as the transfer cylinder 34 rotates. The sheet material P conveyed by the transfer cylinder 34 is delivered to the drum 31 at a position facing the drum 31.

A gripping means (seat gripper) is also provided on the surface of the drum 31, and the tip of the sheet material P is gripped by the gripping means (seat gripper). A plurality of suction holes are dispersedly formed on the surface of the drum 31, and a suction airflow is generated inward from the required suction holes of the drum 31 by the suction means.

The tip of the sheet material P delivered from the transfer cylinder 34 to the drum 31 is gripped by the sheet gripper, and is attracted and supported on the drum 31 by the suction airflow by the suction means, and is conveyed as the drum 31 rotates. Will be done.

The liquid discharge unit 32 includes a discharge unit 33 (33A to 33D) which is a liquid discharge means. For example, the discharge unit 33A uses a cyan (C) liquid, the discharge unit 33B uses a magenta (M) liquid, the discharge unit 33C uses a yellow (Y) liquid, and the discharge unit 33D uses a black (K) liquid. Discharge each. In addition, a discharge unit that discharges a special liquid such as white or gold (silver) can also be used.

The discharge operation of each discharge unit 33 of the liquid discharge unit 32 is controlled by a drive signal corresponding to the print information. When the sheet material P supported on the drum 31 passes through the region facing the liquid discharge unit 32, the liquids of each color are discharged from the discharge unit 33, and an image corresponding to the print information is printed.

The drying unit 40 dries the liquid adhering to the sheet material P at the printing unit 30. As a result, the liquid content such as water in the liquid evaporates, the colorant contained in the liquid is fixed on the sheet material P, and the curl of the sheet material P is suppressed.

The reversing mechanism unit 60 is a mechanism for reversing the sheet material P by a switchback method when double-sided printing is performed on the sheet material P that has passed through the drying unit 40, and the inverted sheet material P is the printing unit 30. It is sent back to the upstream side of the delivery cylinder 34 through the transport path 61 of the above.

The carry-out unit 50 includes a carry-out tray 51 on which a plurality of sheet materials P are loaded. The sheet material P conveyed through the reversing mechanism unit 60 is sequentially stacked and held on the carry-out tray 51.

Next, an example of the head unit constituting the discharge unit will be described with reference to FIG. FIG. 2 is a plan explanatory view of the head unit as viewed from the nozzle surface side.

The head unit 300 is formed by arranging a plurality of heads 100 for discharging liquid in a staggered manner on a head mounting member 302.

Each head 100 has a plurality of rows of nozzles (here, four rows are taken as an example, but the present invention is not limited) in which a plurality of nozzles 104 for discharging liquid are arranged.

Next, an example of the head 100 will be described with reference to FIGS. 3 to 5. FIG. 3 is a cross-sectional explanatory view of the head in the lateral direction (direction orthogonal to the nozzle arrangement direction), FIG. 4 is a plan explanatory view of the temperature control liquid flow path in the line AA of FIG. 3, and FIG. 5 is a plan view of the head. It is a perspective explanatory drawing provided with the explanation of the port of an ink and a temperature control liquid.

In the head 100, a nozzle plate 101 forming the nozzle 104, a flow path plate 102 forming a flow path such as a pressure chamber 106 leading to the nozzle 104, and a diaphragm 103 forming a wall surface of the pressure chamber 106 are sequentially laminated. There is. Further, the head 100 has a piezoelectric actuator 111 as a pressure generating means and a frame member 120 which is a housing portion also serving as a common flow path member.

The piezoelectric actuator 111 has a plurality of columnar piezoelectric elements 112 fixed on the base member 113, and the piezoelectric elements 112 are joined to the diaphragm 103. Further, a wiring member 115 such as a flexible wiring board is connected to the piezoelectric element 112.

The frame member 120 that also serves as the common flow path member forms the common supply flow path 110 that supplies the liquid (ink) to be discharged to the pressure chamber 106.

A temperature control liquid flow path member 131 forming a temperature control liquid flow path 130 in the head 100 for flowing a temperature control liquid (a liquid whose temperature has been adjusted) is joined to the frame member 120. The temperature control liquid flow path member 131 has a temperature control liquid supply port 132a for supplying the temperature control liquid to the temperature control liquid flow path 130, and a temperature control liquid recovery port 133a for collecting the temperature control liquid to the outside. There is.

As a result, in the head 100, the common supply flow path 110, which is the ink flow path, and the temperature control liquid flow path 130 are thermally coupled. Further, the frame member 120 that also serves as the housing portion of the head 100 forms the wall surface of the liquid adjusting flow path 130, and is naturally thermally coupled to the temperature controlling liquid flow path 130.

A case member 150 and a lid member 151 are sequentially laminated on the temperature control liquid flow path member 131.

Then, as shown in FIG. 5, in the case member 150, the temperature connected to the ink supply ports 122 and 122 for supplying ink to the common supply flow path 110 and the temperature control liquid supply port 132a of the temperature control liquid flow path 130. It has a temperature control liquid supply port 132 and a temperature control liquid recovery port 133 connected to the temperature control liquid recovery port 133a.

Next, the liquid (ink) supply system and the temperature control liquid circulation path system according to the first embodiment of the present invention will be described with reference to FIGS. 6 to 8. FIG. 6 is a block explanatory view of the liquid (ink) supply system and the temperature control liquid circulation path system, FIG. 7 is a perspective explanatory view of the assembled state of the ink supply manifold and the temperature control liquid supply manifold, and FIG. 8 is a temperature control liquid. It is sectional drawing of the manifold.

The ink supply system includes a liquid tank (ink tank) 401 that stores the liquid (ink) supplied to the head 100, and an ink that is a liquid supply manifold that distributes and supplies the ink supplied from the liquid tank 401 to a plurality of heads 100. It includes a supply manifold 402. The ink supply manifold 402 and each head 100 are connected by a supply path 403 such as a supply tube.

As shown in FIG. 7, the ink supply manifold 402 is a tubular member having an ink flow path 420 (see FIG. 13 described later) formed therein, and includes an inlet port 421 to which ink is supplied from the ink tank 401. It is provided with an outlet port 422 that supplies ink to each head 100.

The temperature control liquid circulation system includes a temperature control liquid tank 501 for storing the temperature control liquid 510, a liquid feed pump 502 for sending the temperature control liquid 510, and a cooler 511 which is a cooling means for cooling the temperature control liquid 510. A temperature control liquid supply manifold 505 that distributes and supplies the temperature control liquid 510 to each head 100, and a temperature control liquid recovery manifold 506 that recovers the temperature control liquid 510 from each head 100 are provided.

As shown in FIG. 8, the temperature control liquid supply manifold 505 is a plate-shaped member in which a flow path of the temperature control liquid 510 is formed, and has an inlet port 555 to which the temperature control liquid is supplied from the heat exchanger 503. , Each head 100 is provided with an outlet port 556 for supplying a temperature control liquid.

The temperature control liquid supply manifold 505 includes a manifold main body 552 in which a plurality of liquid flow paths 551a to 551d are formed along the longitudinal direction, and a folded-back portion cap 555 attached to both ends of the manifold main body 552. ing.

The liquid flow path 551d is provided with an outlet port 556 for supplying the temperature control liquid 510 to each head 100. The temperature control liquid 510 is supplied from the outlet port 556 to the temperature control liquid supply port 132 via the supply path 513.

Then, as shown in FIG. 7, the temperature control liquid supply manifold 505 is fitted with the ink supply manifold 402, and the temperature control liquid supply manifold 505 and the ink supply manifold 402 are thermally coupled.

The cooler 511 is composed of, for example, a radiator.

The temperature control liquid supply manifold 505 and the temperature control liquid supply port 132 of each head 100 are connected by a supply path 513 such as a supply tube, and the temperature control liquid recovery port 133 of each head 100 and the temperature control liquid recovery manifold 506 are collected. It is connected by a collection path 514 such as a tube.

By driving the liquid feed pump 502, the temperature control liquid 510 stored in the temperature control liquid tank 501 is the liquid feed pump 502, the cooler 511, the temperature control liquid supply manifold 505, each head 100, and the temperature control liquid recovery manifold. It circulates through the circulation path 500 returning to the temperature control liquid tank 501 via 506.

Then, on the temperature control liquid recovery manifold 506, the heat generating portion of the head drive substrate 160 on which the drive waveform generation unit applied to the piezoelectric actuators 111 of the plurality of heads 100 and the power amplification unit for amplifying the waveform are mounted is thermally coupled. ing.

In the system configured in this way, the temperature control liquid 510 is pumped from the temperature control liquid tank 501 by the liquid feed pump 502, passes through the cooler 511 that cools the temperature control liquid 510, and is each from the temperature control liquid supply manifold 505. It is distributed to the head 100.

Then, the temperature control liquid 510 passes through the temperature control liquid flow path 130 of each head 100 to cool the frame member 120 (housing portion) of each head 100, and after passing through each head 100, the temperature control liquid recovery manifold. After being recovered at 506, the head drive board 160 (drive circuit unit) is cooled to cool the power amplification unit and the like, and the process returns to the temperature control liquid tank 501.

On the other hand, the ink is supplied from the ink tank 401 to the ink supply manifold 402 and distributed to each head 100.

Since the temperature control liquid supply manifold 505 and the ink supply manifold 402 are thermally coupled, the ink temperature in the ink supply manifold 402 becomes the same temperature as the temperature control liquid 510 before the ink flows into each head 100. The temperature is adjusted. As a result, the temperature of the ink supplied from the ink supply manifold 402 becomes uniform, and the temperature gradient between the heads 100 and on the nozzle rows 103 and 104 is suppressed (suppression of the temperature gradient in the nozzle row direction).

Here, the circulation path 500 of the temperature control liquid 510 is a head drive substrate 160 on which a frame member 120, a drive waveform generation unit, a power amplification unit for amplifying a waveform, and the like are mounted as a housing portion of the head 100 which is a heat generating portion. Are thermally bonded to each other.

In this case, the heat generation amount of the frame member 120 is smaller than the heat generation amount of the head drive substrate 160. Therefore, the frame member 120 and the head drive substrate 160, which are two heat generating portions that are thermally coupled to the circulation path 500, are arranged in ascending order of heat generation amount, that is, in the present embodiment, the frame member 120 of the head 100 and the head drive. The substrate 160 is thermally coupled to the circulation path 500 in this order.

As a result, the order of cooling by the temperature control liquid is in ascending order of calorific value, and efficient cooling can be performed.

In other words, if a heat generating part with a small calorific value is placed downstream of the heat generating part with a large calorific value, the cooled temperature control liquid is heated by the heat generating part with a large calorific value and the temperature rises, so that the heat generated with a small calorific value is generated. There is a risk that even the heat generated by the part cannot be cooled.

On the other hand, as in the present embodiment, by sequentially cooling the heat generating portion having the smallest calorific value, the thermal heating portion can be reliably cooled without causing a sudden temperature rise of the temperature control liquid. become.

Next, the thermal coupling between the temperature control liquid recovery manifold and the temperature control liquid recovery manifold and the head drive substrate 160 will be described with reference to FIGS. 9 to 12. FIG. 9 is an explanatory cross-sectional view provided for a detailed explanation of the temperature control liquid flow path of the temperature control liquid recovery manifold. FIG. 10 is a perspective explanatory view of a joint portion between the same temperature control liquid recovery manifold and the head drive substrate 160, FIG. 11 is an exploded perspective explanatory view, and FIG. 12 is a side explanatory view of the joint portion.

The temperature control liquid recovery manifold 506 is formed with a temperature control liquid flow path 561 in which the temperature control liquid 510 supplied from the head 100 through the recovery path 514 flows in the direction of arrow A. Further, the temperature control liquid recovery manifold 506 includes an inlet port 565 connected to a plurality of recovery paths 514 and an outlet port 566 for discharging the temperature control liquid to the temperature control liquid tank 501.

The temperature control liquid flow path 561 is provided with a plurality of liquid flow paths along the longitudinal direction and folded flow paths at both ends.

A power amplification unit 161 composed of a MOS-FET that amplifies the drive waveform is mounted on the head drive substrate 160, and a heat sink 162 is provided in contact with the power amplification unit 161.

Therefore, by fixing the heat sink 162 of the head drive board 160 and the temperature control liquid recovery manifold 506 via the heat conductive sheet 163, the temperature control liquid recovery manifold 506 and the power amplification unit 161 of the head drive board 160 are thermally coupled. doing.

Next, the positional relationship between the head 100, the temperature control liquid supply manifold 505, and the temperature control liquid recovery manifold 506 will be described with reference to FIG. FIG. 13 is an explanatory diagram for the same explanation.

The temperature control liquid recovery manifold 506 and the temperature control liquid supply manifold 505 are arranged above the head 100. Therefore, in the present embodiment, the ink supply manifold 402 that is thermally coupled to the temperature control liquid supply manifold 505 is also arranged above the head 100.

The ink supply manifold 402 is connected to the ink supply port 122 of the head 100 via the ink supply path 403. The temperature control liquid supply manifold 505 is connected to the temperature control liquid supply port 132 of the head 100 via the supply path 513. The temperature control liquid recovery manifold 506 is connected to the temperature control liquid recovery port 133 of the head 100 via the recovery path 514.

Since the temperature control liquid recovery manifold 506 and the temperature control liquid supply manifold 505 are arranged above the head 100, high image quality can be obtained without reducing the nozzle density (head arrangement density) of the head 100. .. Further, the distance between the ink supply path 403 and the temperature control liquid supply path 513 can be shortened, and the temperature change in each supply path can be suppressed to be small.

Further, the frame member 120 of the head 100, which is smaller than the heat generation amount of the head drive board 160, is arranged below the head drive board 160, and the frame member 120 of the head 100 and the head drive board 160 are thermally coupled to the circulation path 500 in this order. doing. A head drive substrate 160 that is thermally coupled to the temperature control liquid recovery manifold 506 is arranged above the head 100. As a result, the order of cooling by the temperature control liquid is in ascending order of the amount of heat generated, so that efficient cooling can be performed and the temperature rise of the head 100 can be suppressed.

Further, the head unit 300, the temperature control liquid recovery manifold 506, and the temperature control liquid supply manifold 505 are integrated by the cover 1000. This improves maintainability.

Next, the portion related to the temperature control of the temperature control liquid will be described with reference to the block explanatory diagram of FIG.

The temperature control liquid temperature control means 801 inputs the detection results of the environment temperature sensor 811 that detects the environment temperature TH5 and the temperature control liquid sensor 812 that detects the temperature TH1 of the temperature control liquid at the inlet of the cooler 511.

Further, the temperature control liquid temperature control means 801 inputs a detection result such as a rotation speed sensor 814 that detects the rotation speed of the fan of the radiator constituting the cooler 511.

Then, the temperature control liquid temperature control means 801 performs drive control of the fans constituting the cooler 511 based on these input detection results.

Next, as an operation example of temperature control, an outline when the environmental temperature is less than 25 ° C. will be described.

The temperature is controlled within a predetermined temperature range (25 ° C to 36.5 ° C) of the temperature control liquid. When starting up the device in a low temperature environment, it is necessary to start up the ink temperature to the specified temperature. Therefore, a heating drive waveform excluding the resonance point that does not eject ink is applied to the piezoelectric actuator 111 of the head 100, and the temperature control liquid is generated by the heat generated by the MOS-FET of the head drive substrate 160 and the heat generated by the piezoelectric actuator 111. By heating 510 and circulating the temperature control liquid 510, the circulation path 500 and the ink supply path in the head 100 and in front of the head 100 are heated to a constant temperature.

When controlling the heating of the temperature control liquid 510, the cooler 511 is turned off when the temperature control liquid temperature associated with the ambient temperature is less than a predetermined temperature (threshold temperature) of 25 ° C., and the inlet of the cooler 511 of the circulation path 500. The temperature TH1 of the temperature control liquid 510 is detected, the heat generation duty (Duty) by the piezoelectric actuator 111 is controlled, and the heating control is performed so that the temperature control liquid 510 becomes 25 ° C.

Further, when the temperature of the temperature control liquid 510 shifts to the threshold temperature of 25 ° C. or higher, the heat generation of the MOS-FET of the head drive substrate 160 and the heating control by the piezoelectric actuator 111 are stopped, and the printing standby state is entered.

Further, when continuous printing is started and the temperature of the circulating temperature control liquid 510 reaches the threshold temperature of 25 ° C. or higher, the cooler 511 is driven to bring the temperature of the temperature control liquid 510 within the ambient temperature + 3 ° C. To cool.

Here, the cooling capacity of the cooler 511 is set so that it can be cooled with respect to the calorific value corresponding to the maximum ink amount of the head unit 300. The actual breakdown of the calorific value is the calorific value of the head drive substrate 160 including the power amplification unit that amplifies the drive waveform given to the piezoelectric actuator 111 of the head 100, the calorific value of the piezoelectric actuator 111 in the head 100, and the piezoelectric actuator of the head 100. Select the piezoelectric element 112 that gives the drive waveform of 111. Set the cooling capacity according to the amount of heat generated by the head drive IC.

Next, operation control at startup in a low temperature environment will be described with reference to FIGS. 15 and 16. FIG. 15 is an explanatory diagram of an example of a temperature control liquid temperature control drive waveform, and FIG. 16 is an explanatory diagram of an example of the relationship between the duty (drive frequency) of the temperature control liquid temperature control drive waveform and the environment temperature and the temperature control liquid temperature. Is.

In the start-up state in a low temperature environment, the head temperature, ink temperature, and temperature control liquid temperature are the same as in a low temperature environment, so the ink viscosity is significantly thicker than the room temperature viscosity, and the target ejection characteristics are achieved. I can't get it.

Therefore, when the device is started up in a low temperature environment, a heating drive waveform as shown in FIG. 15 with the resonance point removed is given to the head drive substrate 160 and the piezoelectric element 112 of the head 100.

At the same time, the liquid feed pump 502 is driven to perform the temperature control liquid circulation operation, and the temperature control liquid and the circulation path 500, the temperature rise of the head 100, and the thermal coupling between the ink supply manifold 402 and the temperature control liquid supply manifold 505 are performed. , The temperature rises to near the normal temperature environment temperature.

At this time, the amount of heat generated can be controlled by controlling the drive frequency of the temperature raising drive waveform given to the head drive substrate 160 and the piezoelectric element 112. For example, when the environmental temperature is 10 ° C., the head drive substrate 160 is heated with a calorific value of 8 KW (40 KHz) to steeply raise the temperature in the circulation path 500. As the normal temperature of the ink temperature control target is reached, the drive frequency is reduced so as to reduce the amount of heat generated in order to avoid overshoot.

For example, as shown in FIG. 16, the drive frequency (duty) of the temperature raising drive waveform given to the head drive substrate is changed according to the temperature TH1 of the temperature control liquid flowing into the radiator constituting the cooler 511. As described above, the temperature TH1 is detected by the temperature control liquid sensor 812 at the inlet of the cooler to control the temperature of the cooler.

The head drive board 160 is equipped with eight drive wave generation circuits and a drive waveform amplification unit, and the maximum heat generation amount of the head drive board is 290 W / sheet. In addition, since 11 head drive boards 160 are mounted corresponding to 11 heads constituting a nozzle array for one color, the maximum calorific value of the four colors is 12 KW, so that the low temperature start-up time can be shortened. Become.

The waveform of the heating drive waveform shown in FIG. 15 is a waveform excluding the resonance point of the pressure chamber 106, and the waveform length is set to 14 μm so that the drive frequency is variable to control the calorific value. For example, since the period of 60 KHz is 16.7 μs, if a waveform is created at 14 μs, it can be applied up to 60 KHz. In the present embodiment, a table for controlling the calorific value is created with the calorific value when 40 KHz is applied as 100% (FIG. 16 above).

Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 17 is a block explanatory view of a liquid (ink) supply system and a temperature control liquid circulation path system in the same embodiment.

In the present embodiment, a cooling member 570 that cools the head drive IC 116 that drives the head actuator, such as the waveform generation unit and the power amplification unit of the nozzle drive element mounted on the wiring member 115 of the head 100, is provided.

The head drive IC 116 in the present embodiment is composed of an integrated circuit in which a waveform generation unit, a power amplification unit, and the like mounted on the head drive substrate 160 in the first embodiment are integrated at high density for each nozzle row. It includes circuits such as a waveform generation unit applied to the piezoelectric actuator 111 of 100, an actuator, a power amplification unit that amplifies the waveform, and a control function of each nozzle.

Then, the temperature control liquid is supplied from the temperature control liquid supply manifold 505 to the frame member 120 of the head 100, the temperature control liquid that has passed through the frame member 120 is supplied to the cooling member 570, and the temperature control liquid that has passed through the cooling member 570 is supplied. It is collected in the temperature control liquid recovery manifold 506.

Here, too, the frame member 120, which is the housing portion of the head 100, and the head drive IC 116 are arranged in the circulation path 500 as two heat generating portions having different heat generation amounts. Then, in the present embodiment, in the circulation path 500, starting from the cooler 511, on the downstream side of the cooler 511, in ascending order of calorific value, here, the frame member 120 which is the housing portion, and the head drive IC 116 in that order. Have been placed.

As a result, the order of cooling by the temperature control liquid is smaller than the calorific value, and efficient cooling can be performed.

Next, an example of the cooling member 570 will be described with reference to FIGS. 18 to 20. FIG. 18 is an exploded perspective explanatory view of a state in which the head and the cooling member are separated. FIG. 19 is a partial cross-sectional explanatory view of a direction orthogonal to the nozzle arrangement direction used to explain the temperature control liquid flow path of the cooling member, and FIG. 20 is a nozzle arrangement direction used to explain the thermal coupling between the cooling member and the head drive IC 116. It is a partial cross-sectional explanatory view in the direction orthogonal to.

In the cooling member 570, a temperature control liquid flow path 572 through which the temperature control liquid flows is formed in the heat receiving portion 571. The temperature control liquid flow path 572 is provided with a supply port 573 and a recovery port 574.

The heat receiving portion 571 of the cooling member 570 is thermally coupled to the surface of the head drive IC 116 mounted on the wiring member 115 via the heat transfer sheet 575, and the temperature control liquid 510 flows adjacent to the head drive IC 116. A liquid flow path 572 is arranged.

As a result, as shown by an arrow A in FIGS. 18 and 19, the temperature control liquid 510 flows through the temperature control liquid flow path 572 of the cooling member 570, so that the driver IC 116 is cooled, heat generation is suppressed, and the head is driven. The rise in ink temperature due to heat dissipation from IC116 is suppressed.

Next, the third embodiment of the present invention will be described with reference to FIGS. 21 and 22. FIG. 21 is an explanatory diagram for explaining the configuration of the head unit and the circulation path of the temperature control liquid according to the same embodiment, and FIG. 22 is a perspective explanatory view for explaining the temperature control liquid circulation path of the dual head.

The head unit 300 is formed by arranging two sets of heads (dual heads) 100, 100 for discharging liquid in a staggered pattern.

Then, as shown by the solid arrow A in FIG. 22, the temperature control liquid 510 is supplied from the temperature control liquid supply manifold to the temperature control liquid supply port 132 of one of the two sets of heads 100 and 100. The temperature control liquid that has passed through the frame member 120 of one head 100 is collected from the temperature control liquid recovery port 133. The temperature control liquid 510 collected from one head 100 is supplied to the temperature control liquid supply port 132 of the other head 100, and the temperature control liquid 510 that has passed through the frame member 120 of the other head 100 is supplied from the temperature control liquid recovery port 133. to recover.

The temperature control liquid 510 collected from the temperature control liquid recovery port 133 of the other head 100 is collected in the temperature control liquid recovery manifold 506 through the cooling member 570.

For each head 100, ink is supplied to the ink supply port 122 as shown by the broken line arrow B in FIG.

Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 23 is a block explanatory view of a liquid (ink) supply system and a temperature control liquid circulation path system in the same embodiment.

The circulation path 500 is thermally coupled to the frame member 120 which is the housing portion constituting the head 100, the base member 113 constituting the piezoelectric actuator 11, and the head drive IC 116 as three heat generating portions having different heat generation amounts. There is.

At this time, the frame member 120, the piezoelectric actuator 11, and the head drive IC 116 having different heat generation amounts, when starting from the cooler 511, are in ascending order of heat generation amount, that is, the frame member 120, the base member 113, and the head drive. It is thermally coupled to the circulation path 500 in the order of IC116.

As a result, cooling can be performed efficiently.

Next, a fifth embodiment of the present invention will be described with reference to FIG. FIG. 24 is an explanatory diagram provided for explaining the temperature control liquid circulation system in the same embodiment.

In the present embodiment, the temperature control liquid supply manifold 505 (505A to 505D) and the temperature control liquid recovery correspond to the plurality of head units 300 (33A to 33D) including the plurality of heads 100 of the first embodiment. It is equipped with a manifold 506 (506A to 506D).

A common temperature control liquid tank 501 is provided. The temperature control liquid 510 is branched and supplied from the common temperature control liquid tank 501 to the temperature control liquid supply manifolds 505A and 505B via the liquid feed pump 502A and the radiator 511A (direct connection of 511A1 and 511A2).

Further, the temperature control liquid 510 is branched and supplied from the common temperature control liquid tank 501 to the temperature control liquid supply manifolds 505C and 505D via the liquid feed pump 502B and the radiator 511B (direct connection of 511B1 and 511B2).

On the other hand, the temperature control liquid 510 that has passed through the head unit 300 is collected by the temperature control liquid recovery manifolds 506 (506A to 506D), then aggregated into one and returned to the temperature control liquid tank 501.

Therefore, the circulation path 500A is warmed from the temperature control liquid tank 501 through the liquid feed pump 502A, the radiators 511A1, 511A2, the temperature control liquid supply manifolds 505A and 505B, the head units 300A and 33B, and the temperature control liquid recovery manifolds 506A and 506B. This is the route back to the liquid preparation tank 501.

Similarly, the circulation path 500B passes from the temperature control liquid tank 501 through the liquid feed pump 502B, the radiators 511B1, 511B2, the temperature control liquid supply manifolds 505C and 505D, the head units 300C and 33D, and the temperature control liquid recovery manifolds 506C and 506D. This is the route back to the temperature control liquid tank 501.

Further, each temperature control liquid recovery manifold 506 and the head drive board 160 are thermally coupled to cool the power amplification unit that amplifies the drive waveform of the MOS-FET or the like mounted on the head drive board 160.

Further, also in the present embodiment, similarly to FIG. 13, the frame member 120 of the head 100, which is smaller than the heat generation amount of the head drive board 160, is arranged below the head drive board 160, and the frame member 120 of the head 100 and the head The drive board 160 is thermally coupled to the circulation path 500 in this order. A head drive substrate 160 that is thermally coupled to the temperature control liquid recovery manifold 506 is arranged above the head 100. As a result, the order of cooling by the temperature control liquid is in ascending order of the amount of heat generated, so that efficient cooling can be performed and the temperature rise of the head 100 can be suppressed.

In this embodiment, four radiators 511 are used as cooling means, and two radiators connected in series are connected in parallel to form a mixed connection. However, as in the second embodiment, four radiators are connected. The radiator 511 may be connected in parallel. Further, it is possible to arrange a cooling means in which a plurality of radiators are connected in series, in parallel, or a mixture of series connection and parallel connection.

In the present application, the liquid to be discharged may have a viscosity and surface tension that can be discharged from the head, and is not particularly limited, but the viscosity becomes 30 mPa · s or less at room temperature, under normal pressure, or by heating or cooling. It is preferable that it is a thing. More specifically, solvents such as water and organic solvents, colorants such as dyes and pigments, polymerizable compounds, resins, functionalizing materials such as surfactants, biocompatible materials such as DNA, amino acids and proteins, and calcium. , Solvents, suspensions, emulsions, etc. containing edible materials such as natural pigments, etc., for example, inks for inkjets, surface treatment liquids, constituents of electronic elements and light emitting elements, and formation of electronic circuit resist patterns. It can be used for applications such as liquids for three-dimensional modeling.

The "head" is composed of a piezoelectric actuator (laminated piezoelectric element and thin film piezoelectric element), a thermal actuator using an electric heat conversion element such as a heat generating resistor, a vibrating plate and a counter electrode as an energy generation source for discharging a liquid. Those that use electrostatic actuators are included.

Further, the "device for discharging a liquid" includes not only a device capable of discharging a liquid to a device to which a liquid can adhere, but also a device for discharging the liquid toward the air or the liquid. ..

The "device for discharging the liquid" can also include means for feeding, transporting, and discharging paper to which the liquid can adhere, as well as a pretreatment device, a posttreatment device, and the like.

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

Further, the "device for discharging a liquid" is not limited to a device in which a significant image such as characters and figures is visualized by the discharged liquid. For example, those that form patterns that have no meaning in themselves and those that form a three-dimensional image are also included.

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

The material of the above-mentioned "material to which liquid can be attached" may be paper, thread, fiber, cloth, leather, metal, plastic, glass, wood, ceramics or the like as long as the liquid can be attached even temporarily.

Further, the "device for discharging the liquid" includes, but is not limited to, a device in which the liquid discharge head and the device to which the liquid can adhere move relatively. Specific examples include a serial type device that moves the liquid discharge head, a line type device that does not move the liquid discharge head, and the like.

In addition, as a "device for ejecting liquid", a treatment liquid coating device for ejecting a treatment liquid to the paper in order to apply the treatment liquid to the surface of the paper for the purpose of modifying the surface of the paper, etc. There is an injection granulator that injects a composition liquid in which a raw material is dispersed in a solution through a nozzle to granulate fine particles of the raw material.

In addition, image formation, recording, printing, printing, printing, modeling, etc. in the terms of the present application are all synonymous.

1 Printing device 10 Carry-in part 20 Pretreatment part 30 Printing part 31 Drum 40 Drying part 50 Carry-out part 60 Inversion mechanism part 33 Discharge unit 100 Liquid discharge head (head)
116 Head drive IC
160 Head drive board 402 Ink supply manifold (liquid supply manifold)
505 Temperature control liquid supply manifold 506 Temperature control liquid recovery manifold 511 Cooler (cooling means)
570 Cooling member

Claims (11)

A head that discharges liquid and
A circulation path through which the temperature-adjusted temperature control liquid circulates,
A cooling means for cooling the temperature control liquid is provided.
The circulation path is thermally coupled to at least two heat generating portions having different calorific values.
The two heat generating units are devices that discharge liquids, characterized in that they are thermally coupled to the circulation path in ascending order of heat generation amount when the cooling means is used as a starting point. The heat generating portion includes a housing portion of the head, a pressure generating means, and a drive circuit portion.
The device for discharging a liquid according to claim 1, wherein the calorific value is in the order of the housing portion, the pressure generating means, and the drive circuit portion from the smallest side. The device for discharging a liquid according to claim 1 or 2, wherein the liquid supply path for supplying the liquid to the head and the circulation path are thermally coupled. With multiple heads
A liquid supply manifold that distributes and supplies the liquid to the plurality of heads,
A temperature control liquid supply manifold that distributes and supplies the temperature control liquid to the plurality of heads is provided.
The device for discharging a liquid according to claim 3, wherein the liquid supply manifold and the temperature control liquid supply manifold are thermally coupled. The device for discharging the liquid according to claim 4, further comprising a temperature control liquid recovery manifold that recovers the temperature control liquid from the plurality of heads. The device for discharging a liquid according to claim 5, wherein the temperature control liquid recovery manifold and the drive circuit portion of the head are thermally coupled. The drive circuit unit includes a power amplification unit that amplifies a drive waveform given to the head.
The device for discharging a liquid according to claim 6, wherein the heat sink that is thermally coupled to the power amplification unit and the temperature control liquid recovery manifold are thermally coupled. When the environmental temperature is below the threshold value, the cooling means is turned off and the cooling means is turned off.
Claim 1 is characterized in that the head is provided with a means for controlling the temperature control liquid to be heated to the threshold value by applying a waveform that the liquid does not discharge to drive the drive circuit unit to generate heat. A device for discharging the liquid according to any one of 7. The device for discharging a liquid according to any one of claims 1 to 9, wherein the flow path of the liquid and the flow path of the temperature control liquid are thermally coupled in the head. The first aspect of the present invention is that, when the cooling means is used as a starting point, the heat generating portion having a relatively small calorific value among the two heat generating portions is arranged below the heat generating portion having a large calorific value. A device that discharges the described liquid. With a plurality of heads having different colors of discharged liquid,
A plurality of liquid supply manifolds that distribute and supply the liquid to the plurality of heads,
A plurality of temperature control liquid supply manifolds for distributing and supplying the temperature control liquid to the plurality of heads are provided.
The liquid supply manifold and the temperature control liquid supply manifold are thermally coupled to each other.
The device for discharging the liquid according to claim 3, wherein the temperature control liquid is supplied from the cooling means to the plurality of temperature control liquid supply manifolds, respectively.

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