JP7316744B2 - Inkjet device control method and inkjet device - Google Patents

Description

The present disclosure relates to an inkjet device control method and an inkjet device that eject ink from an inkjet head.

2. Description of the Related Art Conventionally, various inkjet devices that eject ink from an inkjet head have been proposed. Japanese Unexamined Patent Application Publication No. 2002-200002 describes an inkjet device that supplies ink stored in an ink tank to an inkjet head through an ink supply path, and ejects the ink from the inkjet head onto a recording medium such as paper. The ink jet device of Patent Document 1 includes heating means for heating the ink to reduce the viscosity of the ink in order to stabilize the ink discharge amount and the ink discharge speed of the ink jet head.

JP-A-2006-334967 (paragraphs 0007, 0034, 0075)

In the ink-jet apparatus disclosed in JP-A-2003-200002, the ink is heated by a heating means to reduce the viscosity of the ink when the ink is ejected onto the recording medium. However, the volume of the ink expands while the viscosity decreases as the ink is heated during operation. Therefore, when the operation of ejecting the ink is finished and the heating by the heating means is stopped, the ink approaches normal temperature and shrinks in volume. As a result, there is a possibility that air will enter the ink jet head, causing ejection failure in the next operation.

Conversely, for example, if the ink is not sufficiently viscous and the ink is cooled, the volume of the ink will shrink while the viscosity increases as the ink cools during operation. Therefore, when the operation of ejecting the ink onto the recording medium is finished and the cooling is stopped, the ink approaches normal temperature and expands in volume. As a result, ink may leak from the inkjet head. Therefore, it is necessary to control the flow of ink in the ink jet head when changing the temperature such as heating or cooling the ink.

The present disclosure has been made in view of the actual situation described above. An object is to provide an apparatus.

In order to solve the above problems, the present disclosure provides an ink tank that stores ink, a decompression device that reduces the pressure in the ink tank, an inkjet head that ejects the ink from the ink tank, and the inkjet head. A control method for an inkjet device comprising an ink flow path connecting the ink tank, a valve opening and closing the ink flow path, and a temperature changing device for changing the temperature of the ink, the method controlling the decompression device a first step of opening the valve and changing the temperature of the ink by the temperature changing device when performing the operation of ejecting the ink from the inkjet head; and ejecting the ink from the inkjet head. Even after the work is finished and the temperature changing device stops changing the temperature, the valve is opened to allow the ink to move between the ink tank and the inkjet head through the ink flow path. a second step, wherein in the second step, the valve is opened until the temperature of the ink reaches normal temperature while the pressure in the ink tank is reduced by the decompression device. A method of controlling a device is disclosed.

Further, the present disclosure includes an ink tank that stores ink, a decompression device that reduces the pressure in the ink tank, an inkjet head that ejects the ink from the ink tank, and a connection between the inkjet head and the ink tank. a valve for opening and closing the ink flow path; a temperature changing device for changing the temperature of the ink; and a decompression device. After the first process of opening the valve and changing the temperature of the ink by the temperature changing device and the work of ejecting the ink from the inkjet head are finished, and the temperature changing by the temperature changing device is stopped. a second process of opening the valve to enable movement of the ink between the ink tank and the inkjet head through the ink flow path ; The control device discloses an inkjet device, in which, in the second process, the valve is opened while the pressure in the ink tank is reduced by the decompression device until the temperature of the ink reaches normal temperature.

According to the control method of the inkjet device and the inkjet device of the present disclosure, even after the operation of ejecting ink from the inkjet head is completed and the temperature change by the temperature changing device is stopped, the valve is opened and the ink flows through the ink flow path. allow movement of As a result, for example, when the ink in the inkjet head shrinks as it approaches room temperature, the ink that is insufficient due to the shrinkage flows from the ink tank into the inkjet head through the ink flow path due to the change in pressure. Conversely, when the ink in the inkjet head expands as it approaches room temperature, the ink that remains due to the expansion moves from the inkjet head to the ink tank through the ink flow path. As a result, the inflow of air into the inkjet head and the leakage of ink from the inkjet head can be suppressed, and the flow of ink can be appropriately controlled.

It is a figure which shows the electronic device manufacturing apparatus concerning embodiment. It is a block diagram which shows a control apparatus. It is a block diagram which shows a control apparatus. It is a schematic diagram which shows the structure regarding an inkjet head among 2nd shaping|molding units. It is a figure which shows the temperature characteristic of the viscosity of ultraviolet curing resin. FIG. 10 is a diagram showing the details of control of the second modeling unit at the time of activation; FIG. 10 is a diagram showing the details of control of the second modeling unit when stopped. It is a figure which shows the temperature characteristic of the volume ratio of ultraviolet curing resin. FIG. 7 is a diagram showing a state when the ink temperature is lowered according to the embodiment; FIG. 10 is a diagram showing a state when ink temperature is lowered according to a comparative example; FIG. 11 is a diagram showing the control contents of the second modeling unit when stopped according to a comparative example; FIG. 10 is a diagram showing a state when ink temperature rises according to a comparative example; FIG. 7 is a diagram showing a state in which control according to the present embodiment is executed when the ink temperature rises;

(Configuration of electronic device manufacturing equipment)
Preferred embodiments embodying the inkjet device of the present disclosure will be described in detail below with reference to the drawings. FIG. 1 shows an electronic device manufacturing apparatus 10 of this embodiment. The electronic device manufacturing apparatus 10 includes a conveying device 20, a first shaping unit 22, a second shaping unit 24, a mounting unit 26, a third shaping unit 29, and a control device 27 (see FIGS. 2 and 3). Prepare. The conveying device 20 , the first shaping unit 22 , the second shaping unit 24 , the mounting unit 26 and the third shaping unit 29 are arranged on the base 28 of the electronic device manufacturing apparatus 10 . The base 28 has a generally rectangular shape in plan view. In the following description, the longitudinal direction of the base 28 is referred to as the X-axis direction, the lateral direction of the base 28 is referred to as the Y-axis direction, and the direction orthogonal to both the X-axis direction and the Y-axis direction is referred to as the Z-axis direction.

The transport device 20 includes an X-axis slide mechanism 30 and a Y-axis slide mechanism 32 . The X-axis slide mechanism 30 has an X-axis slide rail 34 and an X-axis slider 36 . The X-axis slide rail 34 is arranged on the base 28 so as to extend in the X-axis direction. The X-axis slider 36 is held by an X-axis slide rail 34 so as to be slidable in the X-axis direction. Further, the X-axis slide mechanism 30 has an electromagnetic motor 38 (see FIG. 2), and by driving the electromagnetic motor 38, the X-axis slider 36 is moved to an arbitrary position in the X-axis direction. The Y-axis slide mechanism 32 also has a Y-axis slide rail 50 and a stage 52 . The Y-axis slide rail 50 is arranged on the base 28 so as to extend in the Y-axis direction. One end of the Y-axis slide rail 50 is connected to the X-axis slider 36 . Therefore, the Y-axis slide rail 50 is movable in the X-axis direction. The stage 52 is held by a Y-axis slide rail 50 so as to be slidable in the Y-axis direction. The Y-axis slide mechanism 32 has an electromagnetic motor 56 (see FIG. 2), and drives the electromagnetic motor 56 to move the stage 52 to any position in the Y-axis direction. As a result, the stage 52 is moved to any position on the base 28 by driving the X-axis slide mechanism 30 and the Y-axis slide mechanism 32 .

The stage 52 has a base 60 , a holding device 62 and an elevating device 64 . The base 60 is formed in a flat plate shape, and the base material 70 is mounted on the upper surface thereof. The holding devices 62 are provided on both sides of the base 60 in the X-axis direction. The holding device 62 holds the substrate 70 fixedly on the base 60 by sandwiching both edges in the X-axis direction of the substrate 70 placed on the base 60 . The lifting device 64 is arranged below the base 60 and lifts the base 60 in the Z-axis direction.

The first shaping unit 22 is a unit that shapes wiring on the base material 70 placed on the base 60 of the stage 52 , and has a first printing section 72 and a baking section 74 . The first printing unit 72 has an inkjet head 76 (see FIG. 2), and linearly ejects conductive ink onto the substrate 70 placed on the base 60 . Conductive ink is one example of a fluid containing metal particles of the present disclosure. The conductive ink contains, for example, nanometer-sized metal (silver, etc.) fine particles dispersed in a solvent as a main component, and is cured by being baked with heat. The conductive ink contains, for example, metal nanoparticles with a size of several hundred nanometers or less. The surface of the metal nanoparticles is coated with, for example, a dispersant to suppress aggregation in a solvent.

The inkjet head 76 ejects conductive ink from a plurality of nozzles by, for example, a piezo method using piezoelectric elements. The method for ejecting the conductive ink from the inkjet head 76 is not limited to the piezo method, but may be a thermal method in which the conductive ink is heated to generate bubbles and ejected from a plurality of nozzles. Also, the type of metal nanoparticles contained in the conductive ink is not limited to silver, and may be copper, gold, or the like. Moreover, the number of types of metal nanoparticles contained in the conductive ink is not limited to one type, and may be plural types.

The baking section 74 has an irradiation device 78 (see FIG. 2). The irradiation device 78 includes, for example, an infrared heater that heats the conductive ink ejected onto the substrate 70 . The conductive ink is baked by applying heat from an infrared heater to form wiring. The firing of the conductive ink here means, for example, by applying energy to evaporate the solvent and decompose the protective film of the metal nanoparticles, that is, the dispersant, so that the metal nanoparticles contact or fuse. This is a phenomenon in which the electrical conductivity increases. Then, the wiring can be formed by baking the conductive ink. Incidentally, the device for heating the conductive ink is not limited to the infrared heater. For example, the electronic device manufacturing apparatus 10 may include an infrared lamp, a laser irradiation device for irradiating the conductive ink with a laser beam, or a substrate 70 onto which the conductive ink is discharged, as a device for heating the conductive ink. An electric furnace for heating may be provided.

The second modeling unit 24 is a unit that models a resin layer on the base material 70 placed on the base 60 , and has a second printing section 84 and a curing section 86 . The second printing unit 84 has an inkjet head 88 (see FIG. 2) and ejects an ultraviolet curable resin onto the substrate 70 placed on the base 60 . An ultraviolet curable resin is a resin that is cured by irradiation with ultraviolet rays. The inkjet head 88 may eject the UV curable resin by, for example, a piezoelectric method using piezoelectric elements or a thermal method in which resin is heated to generate bubbles and ejected from a plurality of nozzles.

The curing section 86 has a flattening device 90 (see FIG. 2) and an irradiation device 92 (see FIG. 2). The flattening device 90 flattens the upper surface of the ultraviolet curable resin ejected onto the substrate 70 by the inkjet head 88 . The flattening device 90 makes the thickness of the UV curable resin uniform by, for example, scraping off excess resin with a roller or a blade while leveling the surface of the UV curable resin. Further, the irradiation device 92 has a mercury lamp or an LED as a light source, and irradiates the ultraviolet curing resin discharged onto the substrate 70 with ultraviolet rays. As a result, the ultraviolet curable resin discharged onto the substrate 70 is cured to form a resin layer.

The mounting unit 26 is a unit for placing electronic components on the substrate 70 placed on the base 60 , and has a supply section 100 and a mounting section 102 . The supply unit 100 has a plurality of tape feeders 110 (see FIG. 2) that feed taped electronic components one by one, and supplies the electronic components at each supply position. The electronic component is, for example, a sensor element such as a temperature sensor. Incidentally, the supply of electronic components is not limited to the supply by the tape feeder 110, and may be the supply by a tray.

The mounting section 102 has a mounting head 112 (see FIG. 2) and a moving device 114 (see FIG. 2). The mounting head 112 has a suction nozzle for sucking and holding the electronic component. The suction nozzle is supplied with negative pressure from a positive/negative pressure supply device (not shown), and sucks and holds the electronic component by sucking air. Then, the suction nozzle is supplied with a slight positive pressure from the positive/negative pressure supply device, thereby detaching the electronic component. Further, the moving device 114 moves the mounting head 112 between the supply position of the tape feeder 110 and the substrate 70 placed on the base 60 . As a result, the mounting unit 102 holds the electronic component with the suction nozzle, and arranges the electronic component held with the suction nozzle on the base material 70 .

The third modeling unit 29 is a unit that applies conductive paste onto the base material 70 placed on the base 60 . The conductive paste is, for example, a viscous fluid containing micro-sized metal particles (such as microfillers) in a resin adhesive. Micro-sized metal microparticles are, for example, flake-state metals (such as silver). The metal microparticles are not limited to silver, and may be gold, copper, or multiple types of metals. The adhesive contains, for example, an epoxy-based resin as a main component. The conductive paste is cured by heating and used for forming connection terminals to be connected to wiring, for example. A connection terminal is, for example, a bump connected to a component terminal of an electronic component, an external electrode connected to an external device, or the like.

The third modeling unit 29 also has a dispenser 130 as a device for discharging (applying) the conductive paste. Incidentally, the device for applying the conductive paste is not limited to the dispenser, and may be an inkjet head, a screen printing device, or a gravure printing device. In addition, the term “application” in the present disclosure is a concept that includes the action of ejecting fluid from a nozzle or the like, and the action of applying fluid onto an object by screen printing or gravure printing. The dispenser 130 ejects the conductive paste onto the base material 70 and the resin layer. The discharged conductive paste is heated and hardened by, for example, the baking section 74 of the first modeling unit 22 to form a connection terminal (external electrode, etc.).

Here, the conductive paste contains, for example, metal microparticles with a size of several tens of micrometers or less. In the conductive paste, the adhesive (resin or the like) is cured by being heated, and the conductive paste is cured in a state where the metal flakes are in contact with each other. As described above, in the conductive ink, for example, the metal nanoparticles are fused together by heating to form an integrated metal, and the conductivity is higher than when the metal nanoparticles are only in contact with each other. On the other hand, the conductive paste is cured by bringing the micro-sized metal microparticles into contact with each other by curing the adhesive. For this reason, the resistance (electrical resistivity) of the wiring formed by curing the conductive ink is extremely small, for example, several to several tens of microΩ cm, while the resistance of the wiring formed by curing the conductive paste (several tens to several 1,000 microΩ cm). Therefore, the conductive ink is suitable for forming objects that require a low resistance value, such as low-resistance circuit wiring.

On the other hand, the conductive paste cures the adhesive at the time of curing, so that the adhesion to other members can be enhanced, and the adhesiveness to other members is superior to that of the conductive ink. The other member here is a member to which the conductive paste is applied by discharging or the like, and includes, for example, a resin layer, wiring, and component terminals of electronic components. Therefore, the conductive paste is suitable for molding objects requiring mechanical strength (such as tensile strength), such as connection terminals for fixing electronic components to resin layers. The electronic device manufacturing apparatus 10 of the present embodiment can manufacture an electronic circuit with improved electrical and mechanical properties by selectively using such conductive ink and conductive paste to take advantage of their properties.

Next, the configuration of the control device 27 of the electronic device manufacturing apparatus 10 will be described. As shown in FIGS. 2 and 3, the control device 27 includes a controller 120, a plurality of drive circuits 122, and a storage device 124. FIG. A plurality of drive circuits 122 include the electromagnetic motors 38 and 56, the holding device 62, the lifting device 64, the inkjet head 76, the irradiation device 78, the inkjet head 88, the flattening device 90, the irradiation device 92, the tape feeder 110, and the mounting head 112. , is connected to mobile device 114 (see FIG. 2). Furthermore, the drive circuit 122 is connected to the third modeling unit 29 (see FIG. 3).

The controller 120 comprises a CPU, ROM, RAM, etc., is mainly a computer, and is connected to a plurality of drive circuits 122 . The storage device 124 includes RAM, ROM, hard disk, etc., and stores a control program 126 for controlling the electronic device manufacturing apparatus 10 . The controller 120 can control the operations of the conveying device 20, the first modeling unit 22, the second modeling unit 24, the mounting unit 26, the third modeling unit 29, etc. by executing the control program 126 with the CPU. . In the following description, the controller 120 executing the control program 126 to control each device may simply be referred to as "the device". For example, "the controller 120 controls the second modeling unit 24" means "the controller 120 executes the control program 126 on the CPU and controls the operation of the second modeling unit 24 via the drive circuit 122". means that

The electronic device manufacturing apparatus 10 of the present embodiment manufactures an electronic device including wiring, connection terminals, and electronic parts as a modeled product with the above-described configuration. More specifically, for example, in the control program 126 of the storage device 124, three-dimensional data of each layer obtained by slicing the completed electronic device is set. The controller 120 controls the first modeling unit 22 and the like based on the data of the control program 126 to eject and cure ultraviolet curable resin and the like to manufacture electronic devices.

For example, the controller 120 forms an electronic device on the base material 70 while moving the stage 52 on which the base material 70 is set. The controller 120 moves the stage 52 to the second modeling unit 24 based on the three-dimensional data of the control program 126, for example, when forming a resin layer. The controller 120 repeats ejection of the ultraviolet curing resin by the inkjet head 88 and curing by the curing unit 86 to form a resin layer. Similarly, the controller 120 forms wiring on the resin layer by baking the conductive ink ejected from the first modeling unit 22 in the baking unit 74, for example. Further, the controller 120 heats the conductive paste discharged from the third modeling unit 29 in the baking section 74 to form connection terminals and external terminals on the resin layer. Further, the controller 120 arranges electronic components to be connected to wiring and connection terminals by the mounting unit 26 . In this manner, the electronic device manufacturing apparatus 10 of this embodiment can manufacture an electronic device having a desired shape and structure.

(Configuration of second modeling unit 24)
Next, as an example of the ink of the present disclosure, a case in which an ultraviolet curable resin ejected by the second modeling unit 24 is adopted will be described. In addition, the ink of the present disclosure is not limited to the ultraviolet curable resin, and the conductive ink of the first modeling unit 22 and the conductive paste of the third modeling unit 29 can also be adopted. Therefore, the control for the second shaping unit 24 described below can be similarly performed for the first shaping unit 22 and the third shaping unit 29 .

FIG. 4 schematically shows a configuration related to the inkjet head 88 in the second modeling unit 24. As shown in FIG. As shown in FIG. 4, the second modeling unit 24 includes, in addition to the inkjet head 88 described above, an ink tank 141, a vacuum pump 143, a regulator 145, a pressure gauge 147, a negative pressure supply path 149, an ink flow path 151, a valve 153 is provided.

An ultraviolet curable resin 155 is stored in the ink tank 141 . A vacuum pump 143 is a device that creates a negative pressure in the ink tank 141 . The vacuum pump 143 is connected to the ink tank 141 via a negative pressure supply passage 149 . The vacuum pump 143 reduces the pressure inside the ink tank 141 and supplies negative pressure to the inside of the ink tank 141 under the control of the controller 120 (see FIG. 2).

A regulator 145 is connected between the vacuum pump 143 and the negative pressure supply line 149 . The regulator 145 adjusts the inside of the ink tank 141 to a predetermined negative pressure under the control of the controller 120 . The pressure gauge 147 is a device that detects the pressure inside the negative pressure supply path 149 . The pressure gauge 147 outputs a signal indicating the detected pressure of the negative pressure supply path 149 to the controller 120 . Incidentally, the pressure gauge 147 may be configured to detect the pressure inside the ink tank 141 .

The controller 120 controls the vacuum pump 143 and the regulator 145 based on the signal input from the pressure gauge 147 to control the inside of the ink tank 141 to a desired negative pressure. The controller 120 controls the ejection amount, ejection speed, and the like of the ultraviolet curable resin 155 ejected from the inkjet head 88 by adjusting the negative pressure in the ink tank 141 . The negative pressure value in the ink tank 141 is, for example, a required meniscus pressure value that can maintain the meniscus surface of the UV curable resin 155 at the nozzle port 165 of the inkjet head 88, which will be described later, the specific gravity of the UV curable resin 155, and the nozzle port. It is set based on the water head difference between the opening surface of 165 and the liquid surface of the ink tank 141 .

In addition, as shown in FIG. 4 , the inkjet head 88 includes an in-head channel 157 , a plurality of ink chambers 159 , a heater 161 and a temperature sensor 163 . The ink tank 141 is connected to an in-head channel 157 in the inkjet head 88 via an ink channel 151 . The ink channel 151 connects the inside of the ink tank 141 and the inside of the in-head channel 157 , and moves the ultraviolet curing resin 155 between the ink tank 141 and the in-head channel 157 .

A valve 153 is attached to the ink flow path 151 . The valve 153 is, for example, an electromagnetic valve, and is switched between an open position in which the ink flow path 151 is opened and a closed position in which the ink flow path 151 is closed based on the control of the controller 120 . The letter O in the square shown to the right of valve 153 in FIG. 4 indicates that valve 153 is in the open position. In addition, the letter S in a square shown in FIG. 10, which will be described later, indicates that the valve 153 is in the closed position.

When the valve 153 is in the open position, the UV curable resin 155 moves between the ink tank 141 and the in-head flow path 157 depending on the pressure, as will be described later. Further, when the valve 153 is in the closed position, the ultraviolet curable resin 155 is restricted from moving between the ink tank 141 and the in-head channel 157 .

A plurality of ink chambers 159 of the inkjet head 88 are connected to an in-head channel 157 and supplied with an ultraviolet curable resin 155 from the in-head channel 157 . The inkjet head 88 is formed with a plurality of nozzle ports 165 for ejecting the ultraviolet curable resin 155 . The plurality of nozzle ports 165 are connected to each of the plurality of ink chambers 159 and are connected to the in-head flow path 157 via each ink chamber 159 .

When the pressure in the ink tank 141 is controlled by the controller 120 , the UV curable resin 155 flows through the ink flow path 151 to the in-head flow path 157 according to the magnitude of the negative pressure, and then through each ink chamber 159 . is discharged from the nozzle port 165. The controller 120 adjusts the negative pressure in the ink tank 141 and controls the ejection state (ejection amount, etc.) of the ultraviolet curing resin 155 ejected from the nozzle port 165 . Further, by adjusting the negative pressure in the ink tank 141, the controller 120 maintains the meniscus surface of the ultraviolet curable resin 155 of the nozzle port 165 when ejection is stopped, and prevents the ultraviolet curable resin 155 from leaking. Suppress.

The heater 161 is a temperature changing device that heats the ultraviolet curing resin 155 in the in-head channel 157 . The heater 161 is, for example, an infrared heater. The controller 120 changes the heating temperature of the heater 161 by controlling the power supplied to the heater 161, for example. Here, the ink jet head 88 has a required viscosity range (hereinafter referred to as , sometimes referred to as the required viscosity value) fluctuates.

FIG. 5 shows the temperature characteristics of the viscosity of the ultraviolet curable resin 155. As shown in FIG. The horizontal axis indicates the temperature of the ultraviolet curing resin 155 . The vertical axis indicates the viscosity of the ultraviolet curable resin 155 . As shown in FIG. 5, the viscosity of the UV curable resin 155 gradually decreases as the temperature rises. For example, when the temperature of the room in which the electronic device manufacturing apparatus 10 is installed (from several degrees Celsius to 30 degrees Celsius), that is, at room temperature, when the viscosity of the ultraviolet curable resin 155 is higher than the required viscosity value, the heater 161 is used to heat the ultraviolet curable resin. 155 must be heated to lower its viscosity. For example, using the ultraviolet curable resin 155 having the characteristics shown in FIG. In this case, the temperature of the ultraviolet curable resin 155 must be increased by 35° C. with the heater 161 to reduce the viscosity to less than half. Conversely, if the viscosity of the UV curable resin 155 is lower than the required viscosity value at room temperature, the UV curable resin 155 needs to be cooled to increase the viscosity.

In the following description, as an example, a case will be described in which an ultraviolet curable resin 155 having a viscosity higher than the required viscosity value at room temperature is used, and the ultraviolet curable resin 155 in the in-head flow path 157 is heated by the heater 161 . The position where the heater 161 is installed is not particularly limited. For example, the heater 161 may be installed in the ink chamber 159, the ink flow path 151, the ink tank 141, or the like. Further, the temperature changing device for heating the ultraviolet curing resin 155 is not limited to the infrared heater. For example, the temperature changing device may be a halogen lamp, a laser device, a device using warm water, or the like.

The temperature sensor 163 is a sensor that detects the temperature of the ultraviolet curable resin 155 heated by the heater 161 , for example, the temperature of the ultraviolet curable resin 155 in the in-head channel 157 . The temperature sensor 163 outputs a signal indicating the detected temperature of the ultraviolet curing resin 155 to the controller 120 . The controller 120 detects the temperature of the ultraviolet curable resin 155 based on the signal input from the temperature sensor 163 . Controller 120 controls the heating temperature of heater 161 based on the detected temperature. As a result, the controller 120 can change the temperature of the ultraviolet curable resin 155 in the in-head flow path 157 and the ink chamber 159 to a desired temperature, thereby making the viscosity within the range of the required viscosity value. As a result, the ultraviolet curing resin 155 can be ejected from the inkjet head 88 at a desired ejection amount and ejection speed.

(Contents of control of the second modeling unit 24)
Next, the details of control of the second modeling unit 24 by the controller 120 will be described. First, the contents of control when the second molding unit 24 is activated will be described, and then the contents of control when the second molding unit 24 will be stopped will be described. FIG. 6 shows the control contents of the second modeling unit 24 at startup. The leftmost column in FIG. 6 indicates each step (hereinafter sometimes referred to as S). The second column from the left shows the state of the electronic device manufacturing apparatus 10 . The third column from the left shows the ON/OFF state of the vacuum pump 143 . The fourth column from the left shows the open/closed state of the valve 153 . The fifth column from the left shows the ON/OFF state of the heater 161 . The sixth column from the left indicates the temperature detected by the temperature sensor 163 and indicates the ink temperature T, which is the temperature of the ultraviolet curable resin 155 in the in-head channel 157 . The rightmost column shows the pressure P within the head channel 157 .

First, in S1, the electronic device manufacturing apparatus 10 waits for an activation instruction. For example, the electronic device manufacturing apparatus 10 is in a state where the system is not started although it is connected to the power supply. In this state, the vacuum pump 143 is OFF (stopped), the valve 153 is closed, and the heater 161 is OFF (stopped). The ink temperature T is normal temperature. The pressure P becomes a proper pressure (hereinafter sometimes referred to as a proper pressure). The proper pressure here means, for example, that when the ultraviolet curable resin 155 is not being discharged, the meniscus surface of the nozzle port 165 is maintained so that the ultraviolet curable resin 155 does not leak, and the pressure from the nozzle port 165 to the ink chamber 159 is low. It is the pressure at which air (outside air) does not flow into the side. Further, the appropriate pressure is a pressure that can discharge the ultraviolet curable resin 155 at a desired discharge amount and discharge speed when the ultraviolet curable resin 155 is being discharged.

Next, upon receiving an activation instruction from the user, the controller 120 activates the vacuum pump 143 and controls the regulator 145 to reduce the pressure in the ink tank 141 to a desired negative pressure in S2. Even in this state, the valve 153 is in the closed position.

For example, when the controller 120 detects that the inside of the ink tank 141 has decreased to the target negative pressure based on the detection signal of the pressure gauge 147, the controller 120 switches the valve 153 from the closed position to the open position (S3). An ultraviolet curable resin 155 is supplied from the ink tank 141 through the ink flow path 151 into the in-head flow path 157 . Since the inside of the ink tank 141 is maintained at a desired negative pressure, the pressure P is maintained at an appropriate pressure. The in-head flow path 157 and the ink chamber 159 are filled with the ultraviolet curable resin 155 without causing leakage or the like of the ultraviolet curable resin 155 .

When the controller 120 receives from the user an instruction to start the modeling work for manufacturing the electronic device, the controller 120 turns on the heater 161 (S4). Based on the temperature detected by the temperature sensor 163 , the controller 120 causes the heater 161 to heat the ultraviolet curable resin 155 in the in-head flow path 157 to a target temperature. This target temperature is a temperature at which the viscosity of the ultraviolet curable resin 155 is within the range of the required viscosity value, and is 60° C., for example. When the temperature sensor 163 detects that the ink temperature T of the ultraviolet curing resin 155 has reached the target temperature, the controller 120 starts the modeling work (S4). The controller 120 also controls the vacuum pump 143 and the regulator 145 to adjust the negative pressure of the ink tank 141 and maintain the pressure P at a proper pressure. Even if the ultraviolet curable resin 155 in the head internal flow path 157 is reduced by discharging the ultraviolet curable resin 155 during the modeling work, the reduced ultraviolet curable resin can be 155 is replenished from the ink tank 141 .

Therefore, when the second modeling unit 24 is activated, the controller 120 of this embodiment starts depressurization by the vacuum pump 143 (S2), depressurizes the pressure in the ink tank 141, and then opens the valve 153 (S3, S4). According to this, it is possible to prevent the ultraviolet curable resin 155 from excessively flowing from the ink tank 141 into the inkjet head 88 and leaking from the nozzle port 165 by setting the pressure P to an appropriate pressure.

Next, the details of control when the second modeling unit 24 is stopped will be described. FIG. 7 shows the control contents of the second modeling unit 24 when stopped. First, S6 in FIG. 7 is the state of S4 in FIG. 6, in which the electronic device manufacturing apparatus 10 is manufacturing electronic devices. Next, in S7, after completing the manufacture of the electronic device, the controller 120 turns off the heater 161 (stopped state). By stopping the heating by the heater 161, the temperature of the ultraviolet curable resin 155 in the inkjet head 88 is lowered. The ink temperature T is naturally cooled gradually from the target temperature to normal temperature.

Here, when the UV curable resin 155 is heated in S4 of FIG. 6 or S6 of FIG. 7 as the modeling work is performed, the volume expands. FIG. 8 shows temperature characteristics of the volume ratio of the ultraviolet curable resin 155 . The horizontal axis indicates the temperature of the ultraviolet curing resin 155 . The vertical axis indicates the volume ratio of the ultraviolet curable resin 155, and as an example, indicates the ratio when the volume at 25° C. is taken as 100%.

As shown in FIG. 8, the volume (volume ratio) of the ultraviolet curable resin 155 linearly increases as the temperature rises. For example, when the normal temperature is 25° C. and the target ink temperature T is 60° C., the volume ratio increases by about 10%. In this case, when the molding operation is completed and the heater 161 is stopped, the volume of the UV curable resin 155 is reduced by 10% or more per unit volume while it is cooled from the target temperature to room temperature.

FIG. 10 shows the state when the ink temperature T is lowered according to the comparative example. FIG. 11 shows the control contents of the second modeling unit 24 at the time of stop according to the comparative example. As shown in FIG. 11, the controller 120 of the comparative example switches and closes the valve 153 to the closed position (square in (see letter S in ). As indicated by white arrows in FIG. 10, the volume of the ultraviolet curable resin 155 in the in-head flow path 157 and the ink chamber 159 shrinks as the temperature drops. The pressure P in the in-head channel 157 is reduced as the volume of the ultraviolet curable resin 155 shrinks (S13 in FIG. 11). Then, for example, the ultraviolet curable resin 155 in the ink chamber 159 is drawn toward the in-head flow path 157 , or is pushed toward the in-head flow path 157 by external pressure received from the nozzle port 165 . As a result, as indicated by black arrows in FIG. 10, air flows into the nozzle from the nozzle port 165 before or after the temperature of the ultraviolet curable resin 155 changes to room temperature (S14). If the air flows into the nozzle, there is a risk that the ultraviolet curable resin 155 will not be discharged properly.

On the other hand, in the present embodiment, as shown in S7 of FIG. 7, the controller 120 keeps the valve 153 closed until the ink temperature T drops from the target temperature to normal temperature after the heater 161 is turned off. leave it open. The controller 120 determines whether the ink temperature T has changed to room temperature, for example, based on the temperature detected by the temperature sensor 163 . The method of determining whether or not the temperature has changed to normal temperature is not particularly limited, but the controller 120, for example, when the amount of change in the temperature detected by the temperature sensor 163 is equal to or less than a predetermined amount of change, that is, the temperature of the ink temperature T When the decrease becomes moderate to some extent, it may be determined that the temperature has changed to room temperature. Alternatively, the controller 120 measures the temperature of the ultraviolet curable resin 155 at room temperature in advance before turning on the heater 161, and determines that the temperature has changed to room temperature when the ink temperature T drops to the previously measured temperature. You can

FIG. 9 shows a case where the ink temperature T of this embodiment is lowered. As shown in FIG. 9, the volume of the ultraviolet curable resin 155 in the in-head channel 157 and the ink chamber 159 shrinks as the ink temperature T decreases, as in the comparative example shown in FIG. However, the controller 120 controls the vacuum pump 143 and the regulator 145, adjusts the inside of the ink tank 141 to a desired negative pressure, and makes the pressure P a proper pressure. The controller 120 then keeps the valve 153 open. As a result, as indicated by white arrows in the ink flow path 151 in FIG. 9, the ultraviolet curable resin 155 that is insufficient due to shrinkage is replenished from the ink tank 141 to the inkjet head 88 through the ink flow path 151 . Inflow of air can be suppressed by filling the in-head flow path 157 and the ink chamber 159 with the ultraviolet curable resin 155 and maintaining the proper meniscus surface.

Therefore, in the step of S7 (an example of the second step of the present disclosure), the controller 120 of the present embodiment keeps the pressure in the ink tank 141 reduced by the vacuum pump 143, and the ink temperature T reaches normal temperature. Until then, control is performed to open the valve 153 . According to this, the negative pressure in the ink tank 141 is maintained and the valve 153 is opened until the ink temperature T changes to normal temperature and the change in the volume of the ultraviolet curing resin 155 is completed. Allows ink to move. Inflow of air into the nozzle can be suppressed more reliably.

Further, the controller 120 controls the temperature change of the ultraviolet curable resin 155 by the heater 161 based on the temperature detected by the temperature sensor 163 in steps S4 and S6 (an example of the first step of the present disclosure). Further, in the process of S7, the controller 120 opens the valve 153 based on the ink temperature T detected by the temperature sensor 163 until the ink temperature T reaches normal temperature.

According to this, in the modeling operations of S4 and S6, based on the ink temperature T detected by the temperature sensor 163, by controlling the temperature change of the ultraviolet curable resin 155 by the heater 161, the viscosity of the ultraviolet curable resin 155 is discharged. can be changed to a desired viscosity value suitable for Further, in S7, by opening the valve 153 based on the ink temperature T detected by the temperature sensor 163 until the ink temperature T reaches normal temperature, the inflow of air into the nozzles can be suppressed more reliably.

Next, as shown in S8 of FIG. 7, the controller 120 keeps the valve 153 open even after the ink temperature T changes to room temperature. The controller 120 controls the vacuum pump 143 and the regulator 145, keeps the valve 153 open, and maintains the pressure P at an appropriate level while waiting until receiving an instruction for the next modeling work. As a result, it is possible to quickly start the modeling work while suppressing the inflow of air into the nozzle.

Further, as shown in S9, when the controller 120 receives an instruction from the user to turn off the electronic device manufacturing apparatus 10, the controller 120 switches the valve 153 to the closed position and closes it. As a result, the valve 153 can be closed while the ink temperature T is at room temperature and the pressure P is at an appropriate pressure. After closing the valve 153, the controller 120 turns off the vacuum pump 143 and turns off the electronic device manufacturing apparatus 10 (S10).

Therefore, when stopping the pressure reduction by the vacuum pump 143 , the controller 120 of this embodiment stops the pressure reduction by the vacuum pump 143 after closing the valve 153 . Here, when the vacuum pump 143 is stopped as the power supply of the electronic device manufacturing apparatus 10 is turned off, negative pressure is no longer generated, and the negative pressure in the ink tank 141 is weakened (increased). The meniscus pressure at the nozzle port 165 increases, and there is a risk that the UV curable resin 155 may leak from the nozzle port 165 . On the other hand, the controller 120 of the present embodiment closes the valve 153 before stopping the vacuum pump 143 when the power is turned off, and restricts the movement of the ultraviolet curing resin 155 through the ink flow path 151. Depressurization by the vacuum pump 143 is stopped. Even if the pressure inside the ink tank 141 rises, the UV curable resin 155 can be prevented from flowing into the inkjet head 88 from the ink tank 141, the pressure P can be maintained at a proper pressure, and the leakage of the UV curable resin 155 can be suppressed.

In addition, in the present embodiment, as the ink of the present disclosure, the ultraviolet curable resin 155 used for three-dimensional layered manufacturing and a fluid containing metal particles (conductive ink or conductive paste) are employed. According to this, in the first modeling unit 22, the second modeling unit 24, and the third modeling unit 29 that perform three-dimensional layered modeling by an inkjet method using a fluid containing ultraviolet curable resin 155 and metal particles, Inflow of air through the nozzle port 165 can be suppressed. An electronic device (three-dimensional laminate) can be modeled with higher accuracy.

Further, in the above-described embodiment, the heater 161 that heats the ultraviolet curable resin 155 is used as the temperature changing device of the present disclosure, but similar control is performed even if a cooling device that cools the ultraviolet curable resin 155 is used. be able to. For example, if the viscosity of the ultraviolet curable resin 155 is lower than the required viscosity value at room temperature, it is necessary to cool the ultraviolet curable resin 155 to increase the viscosity during the modeling operation.

FIG. 12 shows the state when the ink temperature rises according to the comparative example. As shown in FIG. 12, for example, when cooling the ultraviolet curing resin 155 , a cooling device 171 is provided in the inkjet head 88 instead of the heater 161 . The configuration of the cooling device 171 (an example of the temperature changing device of the present disclosure) is not particularly limited. The cooling device 171 may be, for example, a device using a Peltier element, a device that circulates water, or the like.

For example, the controller 120 cools the ultraviolet curing resin 155 to a target temperature by the cooling device 171 based on the temperature detected by the temperature sensor 163 (ink temperature T) during the modeling operation. This target temperature is the temperature that raises the viscosity to the required viscosity value. Then, as shown in FIG. 12, the controller 120 of the comparative example closes the valve 153 after the modeling work is finished and before the ink temperature T rises to room temperature. As indicated by white arrows in FIG. 12, the volume of the ultraviolet curable resin 155 in the in-head flow path 157 and the ink chamber 159 expands as the temperature rises. The pressure P in the in-head channel 157 rises as the volume of the ultraviolet curable resin 155 expands. Since the valve 153 is closed, the ultraviolet curing resin 155 in the in-head channel 157 is pushed out into the ink chamber 159 . As a result, the ultraviolet curing resin 155 may leak outside from the nozzle port 165 before or after the temperature changes to normal temperature.

On the other hand, FIG. 13 shows a state in which the control according to the present embodiment is executed when the cooling device 171 is turned off and the ink temperature T rises. For example, the controller 120 keeps the valve 153 open until the ink temperature T rises from the target temperature to normal temperature after the modeling work is completed and the cooling device 171 is turned off. Based on the temperature detected by the temperature sensor 163, the controller 120 determines whether the ink temperature T has changed to room temperature. The controller 120 also controls the vacuum pump 143 and the regulator 145 to maintain the desired negative pressure inside the ink tank 141 .

As a result, as indicated by white arrows in the ink flow path 151 in FIG. 13, the excess ultraviolet curable resin 155 generated due to the volume increase due to the expansion is returned to the ink tank 141 through the ink flow path 151 . It is possible to suppress the UV curable resin 155 from flowing into the ink chamber 159 from the in-head channel 157 and suppress the leakage of the UV curable resin 155 from the nozzle port 165 . In this way, when cooling the ultraviolet curable resin 155 during the modeling operation, the vacuum pump 143 is driven and the valve 153 is opened until the temperature T of the ink of the ultraviolet curable resin 155 rises to room temperature. Leakage of the cured resin 155 can be suppressed.

Incidentally, in the above embodiments, the first shaping unit 22, the second shaping unit 24, and the third shaping unit 29 are examples of inkjet devices. Vacuum pump 143 is an example of a decompression device. The ultraviolet curing resin 155, conductive ink, and conductive ink are examples of ink. The heater 161 and the cooling device 171 are examples of a temperature changing device. Temperature sensor 163 is an example of a temperature detection device. S4 and S6 are examples of the first step and the first process. S7 is an example of the second step, the second process. The ink temperature T is an example of temperature.

As described above, the present embodiment described above has the following effects.
The controller 120 of the present embodiment opens the valve 153 and changes the temperature by the heater 161 when performing the modeling work of controlling the vacuum pump 143 to discharge the ultraviolet curing resin 155 from the inkjet head 88 (S4, S6). Further, even after the modeling work is completed and the temperature change by the heater 161 is stopped, the controller 120 opens the valve 153 to release the UV curable resin 155 between the ink tank 141 and the inkjet head 88 through the ink flow path 151 . (S7).

According to this, when performing a modeling operation in which the ultraviolet curable resin 155 is discharged from the inkjet head 88, the vacuum pump 143 is controlled to reduce the pressure in the ink tank 141, thereby adjusting the discharge amount, discharge speed, and the like. At this time, the valve 153 is opened to change the temperature of the ultraviolet curing resin 155 by the heater 161 . As a result, the temperature of the ultraviolet curable resin 155 can be changed to change the viscosity of the ultraviolet curable resin 155 to a required viscosity value suitable for ejection. Here, when the vacuum pump 143 is stopped, it is necessary to close the valve 153 to restrict the movement of the ultraviolet curing resin 155 between the ink tank 141 and the inkjet head 88 . On the other hand, since the temperature of the ultraviolet curable resin 155 is changed during the modeling work, when the temperature change is stopped after the work is finished and the valve 153 is closed, the volume of ink remaining in the inkjet head 88 fluctuates. For example, when heating with the heater 161, air flows into the inkjet head 88 due to contraction (see FIG. 10). As a result, there is a possibility that ejection failure will occur when the next modeling operation is performed. Conversely, when the cooling device 171 is used for cooling, the ultraviolet curing resin 155 may leak from the inkjet head 88 due to expansion.

Therefore, the controller 120 opens the valve 153 to allow the movement of the ultraviolet curable resin 155 through the ink flow path 151 even after the modeling work is completed and the temperature change by the heater 161 or the like is stopped. As a result, for example, when the ultraviolet curable resin 155 in the inkjet head 88 shrinks as it approaches room temperature, the insufficient amount of ultraviolet curable resin 155 due to shrinkage is released from the ink tank 141 through the ink flow path 151 by the change in pressure. Flow into 88. Conversely, when the ultraviolet curable resin 155 in the inkjet head 88 expands as it approaches room temperature, the excess ultraviolet curable resin 155 due to the expansion moves from the inkjet head 88 to the ink tank 141 through the ink flow path 151 . As a result, the inflow of air into the inkjet head 88 and the leakage of the ultraviolet curable resin 155 from the inkjet head 88 can be suppressed, and the flow of the ultraviolet curable resin 155 can be appropriately controlled.

The present disclosure is not limited to the above-described embodiments, and can be implemented in various modes with various modifications and improvements based on the knowledge of those skilled in the art.
For example, in the above embodiment, the controller 120 opens the valve 153 until the temperature of the ultraviolet curable resin 155 reaches normal temperature, but the valve 153 may be closed before the temperature reaches normal temperature.
Also, the controller 120 determines whether or not the ink temperature T of the ultraviolet curable resin 155 has changed to room temperature based on the temperature detected by the temperature sensor 163, but the method of determination is not limited to this. For example, the controller 120 may use a viscosity sensor that directly detects the viscosity of the ultraviolet curable resin 155 to determine whether the viscosity of the ultraviolet curable resin 155 has reached normal temperature, that is, whether the ink temperature T has reached normal temperature. good.
Further, the controller 120 does not need to determine whether the ink temperature T has reached normal temperature. For example, the controller 120 may open the valve 153 for a certain period of time after the heater 161 is turned off. This certain period of time is, for example, the period of time required for the ultraviolet curable resin 155 to change from the target temperature to normal temperature, which is measured in advance. That is, the controller 120 may use time to determine whether the valve 153 is open or closed.

Further, in the above embodiment, in S7 of FIG. 7, the controller 120 drives the vacuum pump 143 to open the valve 153 while maintaining the negative pressure in the ink tank 141. However, the present invention is not limited to this. For example, the controller 120 may stop the vacuum pump 143 and close the valve 153 before the negative pressure in the ink tank 141 drops. Then, the controller 120 may stop the vacuum pump 143 and wait until the next modeling operation with the valve 153 closed. Therefore, the vacuum pump 143 may be stopped until the temperature of the ultraviolet curable resin 155 changes to room temperature. In this case as well, until the negative pressure in the ink tank 141 is lowered without closing the valve 153, the movement of the ultraviolet curable resin 155 through the ink flow path 151 is promoted, and the inflow of air and the deterioration of the ultraviolet curable resin 155 are prevented. Leakage can be suppressed.
In addition, in S8 of FIG. 7, the controller 120 receives an instruction to turn off the power in S9 after the temperature of the ultraviolet curable resin 155 has changed to room temperature. On the other hand, for example, based on the temperature detected by the temperature sensor 163, if the controller 120 receives an instruction to turn off the power before the UV curable resin 155 is cooled down to room temperature, the controller 120 issues a warning and cools down to room temperature. The OFF control of the vacuum pump 143 or the like may be put on standby until the operation is completed. Alternatively, the controller 120 waits for the vacuum pump 143 to be turned off until the temperature is cooled down to room temperature without issuing a warning (without notifying the user), and closes the valve 153 after the temperature reaches room temperature. Then, the vacuum pump 143 may be turned off and the power may be turned off.
Further, the controller 120 opens the valve 153 in the standby state after the room temperature in S8, but the valve 153 may be closed. The controller 120 may also close the valve 153 to temporarily stop the vacuum pump 143 . Then, the controller 120 may activate the vacuum pump 143, switch the valve 153, or the like when receiving an instruction for the next modeling work.

When the controller 120 stops the vacuum pump 143 to stop the system, the controller 120 closes the valve 153 (S9) and then stops the vacuum pump 143 (S10). However, the controller 120 may simultaneously execute control to close the valve 153 and control to stop the vacuum pump 143 . Alternatively, the controller 120 may close the valve 153 before stopping the vacuum pump 143 and reducing the negative pressure of the ink tank 141 .
Further, the controller 120 may open the valve 153 before the vacuum pump 143 reduces the inside of the ink tank 141 to a desired negative pressure at startup.

In addition, in the above embodiment, the ink of the present disclosure employs the ultraviolet curable resin 155, the conductive paste, and the conductive ink used for three-dimensional layered manufacturing, but the ink is not limited to this. The inks of the present disclosure may be, for example, inks used in printing. That is, the method for controlling an inkjet device according to the present disclosure can be similarly applied to any device, such as an inkjet printer, that ejects ink using an inkjet method and changes the temperature of the ink during operation.

22 first shaping unit (inkjet device), 24 second shaping unit (inkjet device), 29 third shaping unit (inkjet device), 76, 88 inkjet head, 141 ink tank, 143 vacuum pump (decompression device), 151 ink Flow path, 153 valve, 155 ultraviolet curing resin (ink), 161 heater (temperature changing device), 163 temperature sensor (temperature detecting device), 171 cooling device (temperature changing device), T ink temperature (temperature).

Claims (6)

an ink tank that stores ink;
a decompression device for decompressing the pressure in the ink tank;
an inkjet head that ejects the ink from the ink tank;
an ink flow path connecting the inkjet head and the ink tank;
a valve that opens and closes the ink flow path;
a temperature changing device for changing the temperature of the ink;
A control method for an inkjet device comprising
a first step of opening the valve and changing the temperature of the ink by the temperature changing device when the ink is discharged from the inkjet head by controlling the decompression device;
Even after the operation of ejecting the ink from the inkjet head is completed and the change of temperature by the temperature changing device is stopped, the valve is opened and the ink flow path is passed between the ink tank and the inkjet head. a second step of allowing movement of said ink from
including
In the second step, the ink jet device control method includes opening the valve while the pressure in the ink tank is reduced by the decompression device until the temperature of the ink reaches normal temperature. The inkjet device is
further comprising a temperature detection device that detects the temperature of the ink in the inkjet head,
The temperature changing device
changing the temperature of the ink in the inkjet head;
In the first step,
controlling temperature change of the ink by the temperature changing device based on the temperature detected by the temperature detecting device;
In the second step,
2. The method of controlling an inkjet device according to claim 1 , wherein the valve is opened until the temperature of the ink reaches normal temperature based on the temperature detected by the temperature detection device. 3. The method of controlling an inkjet device according to claim 1, wherein, when stopping the pressure reduction by the pressure reduction device, the pressure reduction by the pressure reduction device is stopped after the valve is closed. 4. The inkjet device according to any one of claims 1 to 3, wherein when the inkjet device is started, the pressure reduction by the pressure reduction device is started, and after the pressure in the ink tank is reduced, the valve is opened. control method. 5. The method of controlling an inkjet device according to any one of claims 1 to 4 , wherein the ink is a fluid containing an ultraviolet curable resin used for three-dimensional layered manufacturing and metal particles. an ink tank that stores ink;
a decompression device for decompressing the pressure in the ink tank;
an inkjet head that ejects the ink from the ink tank;
an ink flow path connecting the inkjet head and the ink tank;
a valve that opens and closes the ink flow path;
a temperature changing device for changing the temperature of the ink;
a first process of opening the valve and changing the temperature of the ink by the temperature changing device when performing the task of discharging the ink from the inkjet head by controlling the decompression device; Even after the operation of ejecting the ink is finished and the temperature change by the temperature changing device is stopped, the valve is opened to allow the ink flow between the ink tank and the inkjet head through the ink flow path. a control device that executes a second process that enables movement;
with
The control device is
In the second process, the ink jet device is configured such that the valve is opened while the pressure in the ink tank is reduced by the decompression device until the temperature of the ink reaches normal temperature.

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