JP2008279598A - Inkjet recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet recorder which enables a length of a printing head cable to be freely set and suppresses enlargement of a printing head. <P>SOLUTION: The inkjet recorder which carries out printing with ink particles deflected by charging the ink particles jetted from a nozzle 700 is equipped with the printing head 910 which includes the nozzle and a gutter 704 that collects the ink particles not used for printing and a body which connects with a channel that supplies the ink to the printing head and to a channel where the ink collected from the gutter flows, and which includes both an ink container 852 that stores the ink collected from the gutter and a supply pump 602 that sends out the ink from the ink container. An ejector 500 which connects with the gutter and the ink container is installed inside the printing head. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an ink jet recording apparatus that continuously ejects ink that becomes particle from a nozzle.

  In general, an ink jet recording apparatus that continuously ejects ink that is atomized from a nozzle connects a print head having a nozzle, an ink container that stores ink, a main body having a supply pump that pressurizes the ink, and the print head and the main body. And a print head cable provided with an ink transport tube.

  The ink stored in the ink container is pressurized by a supply pump inside the main body and supplied to the print head. Ink supplied to the print head is continuously ejected from nozzles provided in the print head during operation of the apparatus. Upon ejection, the excited ink is turned into particles (droplets).

  Among the ink particles (also referred to as ink droplets) ejected from the nozzles, those used for printing are charged and deflected, and these ink particles fly to the object to be printed. A collection of ink particles adhering to the surface of the printing material forms dot characters.

  On the other hand, among the ink particles ejected from the nozzle, those that are not used for printing are not charged or deflected, and these ink particles enter the gutter connected to the recovery path. The collection path is connected to the ink container via a collection pump. Therefore, the ink that has entered the gutter is transported through the recovery path and recovered into the ink container due to the pressure difference caused by the recovery pump.

JP 2006-255981 A

  Ink recovery is performed by setting a negative pressure in the recovery path. However, since the gutter is open to the atmosphere, air is sucked into the recovery path simultaneously with the ink. Since air is a compressive fluid, it expands in the recovery path due to negative pressure, and becomes a factor that reduces the negative pressure generated in the gutter. The longer the negative pressure path, the greater the amount of air contained in the negative pressure path, and the greater the negative pressure decrease in the gutter. For this reason, when the negative pressure in the gutter is insufficient, ink overflows from the gutter and may contaminate the inside of the print head and the user's equipment.

  As a conventional ink jet recording apparatus, as disclosed in Patent Document 1, one in which a collecting diaphragm pump is provided inside a main body is known as one of collecting methods. In this method, since the negative pressure path does not include the print head cable, the length of the print head cable can be freely set, and restrictions on the layout of the user equipment can be eliminated.

  However, in this method, restrictions on the layout of user equipment could be eliminated, but on the other hand, when installing the diaphragm pump inside the print head, in addition to the diaphragm and the pressurizing chamber that pressurizes the ink by the operation of the diaphragm, a diaphragm is installed. It is necessary to install at least a driving source such as a motor for operation and a connecting member for transmitting the power of the driving source to the diaphragm. In particular, the installation of the drive source and the connecting member requires a large space, which has been a factor in increasing the size of the print head.

  In order to solve the above-mentioned problems, an ink jet recording apparatus according to the present invention includes an ejector that is provided with an ejector inside a print head, an ejector supply pump that supplies ink to the ejector, and a suction port that generates negative pressure by the ejector action. And the gutter have a communication structure.

  According to the present invention, it is possible to realize an ink jet recording apparatus that can freely set the length of the print head cable and includes a small print head.

  Embodiments of the present invention will be described below with reference to the drawings. First, an overview of the ink jet recording apparatus will be described with reference to FIG. The ink jet recording apparatus according to the present embodiment includes a main body 900 having a control system including an electronic circuit that controls the operation of the main body and each unit, and a circulation system including a path for supplying and collecting ink, and a nozzle that ejects ink. And a print head cable 920 that connects the main body 900 and the print head 910. A touch panel type liquid crystal display device 930 serving as an interface with the user is provided on the upper part of the main body 900. The touch panel type liquid crystal display device 930 can select and execute various commands / operations by touching the surface of the user. As an example of the operations, the user can display print contents and setting contents. You can check and change.

  Next, the internal structure of the main body will be described with reference to FIG. The inside of the main body 900 has a control system area 800 in the upper part and a circulation system area 850 in the lower part, and has a structure that is functionally separated vertically.

  In the control system area 800, a power source 801, a control board 802, a touch panel type liquid crystal display device 930, and the like are installed, and are connected by a power line, a control line, etc., not shown.

  The control board 802 executes various controls such as display control of the touch panel type liquid crystal display device 930, operation control of circulation system components such as a pump and a solenoid valve, which will be described later, and charging / deflection control for ink particles ejected from the print head 910. In addition to the above configuration, the control system area 800 is provided with a touch panel type liquid crystal display device 930 as a liquid crystal unit (not shown) outside the main body 900 to improve user operability, and the liquid crystal unit and the main body 900 are connected by a cable. It is good also as the structure which carried out.

  In the circulation system area 850, a flow path board 851 provided with ink and solvent flow paths is installed. On the flow path board 851, a circulation system component pump 853, an electromagnetic valve 854, and the like are attached to the same front side of the main body 900 as the touch panel type liquid crystal display device 930. FIG. 3 shows an example in which the ink container 852 is attached to the flow path board 851. In addition to this example, in order to make it easier to replenish ink, the main body is connected to the flow path board 851 by piping. It may be arranged at a position closer to the front surface of 900. This is because if a door that opens the lower part of the main body 900 is provided on the lower front surface of the main body 900, replenishment and maintenance are easier if the ink container 852 is provided further forward.

  Next, how ink is ejected from the nozzles in the print head will be described with reference to FIG. Ink supplied from the main body 900 to the nozzle 700 in the print head 910 through the print head cable 920 is vibrated by the piezoelectric element 701. The vibrated ink is made into particles (droplets) after being ejected from the nozzle 700. The direction of ink ejection is indicated by an arrow 720.

  Of the ink particles 710, the ink particles 711 used for printing are charged by the charging electrode 702 and are deflected by the deflection electrode 703 so as to fly to the printed material. On the other hand, the ink particles 712 that are not used for printing are hardly affected by charging and deflection at the charging electrode 702 and the deflection electrode 703 and enter the gutter 704 that is forward of the ejection direction from the nozzle 700, and are allowed to pass through the print head cable 920. It is conveyed to a circulation system component in the main body 900 through a flexible collection pipe.

  Although not shown in FIG. 4, the control substrate 802 controls the operations of the piezoelectric element 701, the charging electrode 702, and the deflection electrode 703 through control lines in the print head cable 920.

  FIG. 5 is a schematic diagram of an ink circulation path of an embodiment of a conventional ink jet recording apparatus. The ink supply path 600 is a path that leads from the ink container 852 inside the main body 900 to the nozzle 700 inside the print head 910 through the print head cable 920. The flow direction of the ink supply path 600 is indicated by an arrow 620.

  In the ink supply path 600, first, as components provided inside the main body 900, an electromagnetic valve 601 that opens and closes a flow path from the ink container 852, and sucks ink from the ink container 852 and transports it in the ink supply path 600. For this purpose, a supply pump 602 that pressurizes the ink, a filter 603 that filters the ink supplied from the supply pump 602 and collects dust, and a pressure reducing valve 604 that can adjust the ink pressure are provided.

  Inside the print head 910, ink is supplied from the ink supply path 600 to the nozzle 700, or a solvent supplied from a solvent tank (not shown) provided in the circulation system area 850 of the main body 900 is supplied to the nozzle 700. Alternatively, a switchable three-way solenoid valve 605 is provided.

  The ink recovery path 610 passes from the gutter 704 inside the print head 910 through the print head cable 920 to the ink container 852 inside the main body 900. The flow direction of the ink recovery path 610 is indicated by 621. A recovery pump 611 is provided in a path inside the main body 900 in the recovery path 610.

  In the conventional configuration shown in FIG. 5, the print head cable 920 is included in the negative pressure path from the recovery pump 611 to the gutter 704, and printing is performed in order to prevent ink overflow due to insufficient negative pressure in the gutter 704. There was a problem that the length of the head cable 920 had to be limited.

  FIG. 6 shows a schematic diagram of an ink circulation path in another embodiment of a conventional ink jet recording apparatus. The difference from the embodiment shown in FIG. 5 is that the recovery pump 611 is not inside the main body 900 but inside the print head 910.

  According to this configuration, the print head cable 920 is not included in the negative pressure path from the recovery pump 611 to the gutter 704, and there is an advantage that the length of the print head cable 920 can be freely set. On the other hand, in this configuration, it is necessary to install a driving source of a pump such as a motor and a connecting member for transmitting the power of the driving source to the pump operating unit in the print head 910, and there is a problem that the print head 910 is enlarged. there were.

  FIG. 1 is a schematic diagram of an ink circulation path according to an embodiment of the inkjet recording apparatus of the present invention. The difference from the conventional embodiment shown in FIG. 6 is that an ejector 500 is installed in the print head 910 instead of the recovery pump 611, and an ejector supply pump 550 that supplies ink to the ejector 500 is provided in the main body 900. It is.

  The ejector 500 includes a supply port 501 that supplies ink as a fluid, a suction port 502 that generates a negative pressure due to the ejector action, and a discharge port 503 that discharges fluid. The supply port 501 communicates with the ejector supply pump 550, the suction port 502 communicates with the gutter 704, and the discharge port 503 communicates with the ink container 852.

  The flow direction of the ink, which is the fluid in the path 510 connecting the supply port 501 and the ejector supply pump 550, is indicated by an arrow 520, the flow direction of the ink in the path 511 connecting the suction port 502 and the gutter 704 is indicated by an arrow 521, and the discharge port 503. The direction of ink flow in the path 512 connecting the ink container 852 and the ink container 852 is indicated by an arrow 522. The ink path on the upstream side of the ejector supply pump 550 communicates with the ink container 852.

  In this embodiment, in addition to the ink supply path 600 for supplying ink to the nozzles, the ink container 852 is provided with a path 510 through which ink circulates through the ejector 500, and the ink flow in the path 510, which is the ink circulation path, is used. To generate negative pressure. Using this negative pressure, the ink collection path 511 is made negative from the gutter 704 and ink is collected from the gutter 704 to the ink container 852. A path 510 includes a path for supplying ink from the ink container 852 to the ejector 500 via the ejector supply pump 550, and ink collected by the gutter 704 connected to the ejector 500 and ink supplied to the ejector 500. And a route to collect together.

  FIG. 7 shows a schematic diagram of an ink circulation path of another embodiment in the ink jet recording apparatus of the present invention. A difference from the embodiment shown in FIG. 1 is that a branch 400 is provided in the upstream path of the ejector supply pump 550, one path being opened to the ink container 852 and the other path being opened to the atmosphere through the opening 401. It is that you are. Further, an electromagnetic valve 402 is provided between the branch 400 and the ink container 852 and between the branch 400 and the opening 401 so that the working fluid of the ejector supply pump 550 can be switched to ink or air. According to this configuration, when the apparatus is stopped, the ink remaining in the path 510 and the path 512 can be replaced with air, and the ink can be prevented from sticking in the path.

  FIG. 8 shows a schematic diagram of an ink circulation path of another embodiment of the ink jet recording apparatus of the present invention. A difference from the embodiment shown in FIG. 1 is that a mechanism for blocking the path 511, such as an electromagnetic valve 300, is provided in the ink recovery path 511 between the suction port 502 of the ejector 500 and the gutter 704. According to this configuration, by closing the solenoid valve 300 when the apparatus is stopped, the communication between the ejector 500 and the atmosphere can be cut off, and the ejector 500 prevents the solvent in the ink from evaporating and the ink is dried and fixed. Operation can be provided.

1 is a schematic diagram of a circulation path of an embodiment of an ink jet recording apparatus of the present invention. 1 is a schematic view of an embodiment of an inkjet recording apparatus of the present invention. FIG. 2 is a schematic view of the inside of the main body of an embodiment of the inkjet recording apparatus of the present invention. The figure which shows a mode that an ink is ejected from the nozzle of one Embodiment of the inkjet recording device of this invention. FIG. 6 is a schematic diagram of a circulation path of an embodiment of a conventional ink jet recording apparatus. FIG. 6 is a schematic diagram of a circulation path of an embodiment of a conventional ink jet recording apparatus. 1 is a schematic diagram of a circulation path of an embodiment of an ink jet recording apparatus of the present invention. 1 is a schematic diagram of a circulation path of an embodiment of an ink jet recording apparatus of the present invention.

Explanation of symbols

500 Ejector 550 Ejector Supply Pump 600 Ink Supply Path 602 Supply Pump 610 Ink Recovery Path 611 Recovery Pump 700 Nozzle 704 Gutter 800 Control System Area 850 Circulation System Area 852 Ink Container 900 Main Body 910 Print Head 920 Print Head Cable 930 Touch Panel Type Liquid Crystal Display Device

Claims (5)

  In an ink jet recording apparatus that performs printing with ink particles that are deflected by charging and discharging ink particles ejected from a nozzle, the print head having the nozzle and a gutter that collects ink particles that are not used for printing, and ink in the print head A main body having an ink container for storing ink collected from the gutter and a supply pump for delivering ink from the ink container, connected to a flow path for supplying the ink and a flow path for ink collected from the gutter. And an ejector connected to the gutter and the ink container in the print head.   2. The ink jet recording apparatus according to claim 1, further comprising an ejector supply pump for supplying ink to the ejector, wherein the suction port for generating a negative pressure of the ejector is the gutter, and the discharge port for discharging the fluid is the ink container. An ink jet recording apparatus communicating with the printer.   3. The ink jet recording apparatus according to claim 2, wherein a branch is provided in an upstream path of the ejector supply pump, wherein one path leads to the ink container and the other leads to the atmosphere.   3. The ink jet recording apparatus according to claim 2, wherein a mechanism for blocking the path is provided in a path connecting the suction port of the ejector and the gutter.   In an inkjet recording apparatus that performs printing with ink particles that are deflected by charging and discharging ink particles ejected from a nozzle, the nozzle, a gutter that collects ink particles that are not used for printing, and ink collected by the gutter. A main body having a print head having an ejector for sucking and a supply pump for delivering ink from an ink container for storing ink, and the nozzle from the main body to the print head. An ink jet recording apparatus provided with a flow path for supplying ink to the apparatus, a flow path for supplying ink from the main body to the ejector, and a flow path for collecting ink from the ejector to the ink container.

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