JP2010125756A - Printing head for ink jet recording device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printing head for an ink jet recording device having a configuration capable of confirming the shape of an ink particle even if the fixing position of a nozzle is set into one position regardless of a difference in the bore diameter of the nozzle. <P>SOLUTION: A base plate 2 having a particle checking window 1 with a length enabling transmission of strobe light is used in a range equal to a difference in distance from an ink ejection port 5 to the place where particles of ink are formed, which occurs due to a difference in the diameter of the opening of the nozzle. Thus, even in the case where the nozzle is fixed in one position, strobe light is transmitted between charging electrodes 7, and the shape of a particle can be checked. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a print head for an ink jet recording apparatus, for example, a print head having a window for confirming the shape of ink particles.

  A print head used in an inkjet recording apparatus is partitioned by a base plate to protect electrical components such as a substrate, a signal line, and a strobe (LED) for confirming the state of particle creation from a liquid such as a cleaning liquid. It has a structure. In the print head, electrical components are arranged on the back side of the base plate, and nozzles, charging electrodes, and deflection electrodes of mechanical components related to printing are mounted on the front side of the base plate.

  In the printing operation of the ink jet recording apparatus, in order to change the ink ejected from the nozzle from the ink in the ink column state to the ink particle state, an appropriate vibration is applied to the ink column from the excitation wall serving as a vibration source provided in the nozzle. Give regularly. Then, adjustment is made so that ink particles are formed in the charging electrode, and a charging voltage that becomes a character signal corresponding to each character is charged at the timing when the ink is turned into particles. The charged ink particles then fly between the two opposing deflection electrodes by the ink pressure ejected from the nozzle. The deflection electrodes are generated between the deflection electrodes by applying a high voltage to one of the + side deflection electrodes and installing one of the − side deflection electrodes. While ink particles fly in an electrostatic field, printing is performed by being deflected according to the amount of charge and adhering to the substrate. When performing the printing, it is necessary to give an appropriate vibration to make the ink particles. When the amount of vibration is small or large, the ink does not form particles or generates satellites. The generated satellite cannot give normal charge to the ink particles, and the ink particles cannot be attached to a desired position, and the printing is disturbed.

  As a guideline for determining whether or not the ink particles are optimal, the ink particle shape is confirmed. As a method of confirmation, light is emitted in synchronization with the frequency of the vibration source provided in the nozzle by a strobe mechanism disposed on the back side of the base plate. The base plate is provided with a particle confirmation window with a secret (seal) property to transmit the strobe light from the back side of the base plate to the front side of the base plate, and the strobe light is sent between the charged electrodes to check the particle shape. Is going. The configuration of the conventional ink particle confirmation window will be described in comparison with the present invention with reference to FIGS.

  In addition, in the ink jet recording apparatus, nozzles having a plurality of types of nozzle diameters are prepared as a lineup in order to cope with various print sizes requested by the user.

Japanese Unexamined Patent Publication No. 7-76076

  When the nozzle diameter is different, the optimum condition for ink particle formation also changes, and a difference in the distance from the ink ejection port of the nozzle to the particle formation place occurs. Therefore, if the fixed position is set to the same location for all types of nozzles with different nozzle diameters, the location where the particles are made and the particle confirmation window will be misaligned, making it impossible to send the strobe light between the charged electrodes. The shape cannot be confirmed.

  For this reason, in the conventional ink jet recording apparatus (FIGS. 3 to 5), a plurality of nozzle fixing positions are prepared, and the nozzles are fixed to the fixing positions corresponding to the nozzle diameters to adjust the deviation.

  However, there are also disadvantages in this case. That is, when the nozzle is removed during the print head maintenance operation and the reassembly or replacement operation occurs, the nozzle fixing position may be mistakenly inadvertently. When printing is resumed by attaching a nozzle to the wrong place, the distance from the nozzle tip to the non-printed material changes, and as a result, the print quality may deteriorate.

  The present invention has been made in view of such a situation, and ink jet recording having a configuration in which the shape of the ink particles can be confirmed even when the nozzle fixing position is set to one type regardless of the difference in nozzle diameter. An apparatus print head is provided.

  In order to solve the above problems, in the present invention, a particle confirmation window having a length capable of transmitting strobe light in the same range as a difference in distance from an ink ejection port to a place where particles are formed due to a difference in nozzle diameter. Use a base plate with Thus, even if the nozzle fixing position is one, the light of the strobe is sent between the charging electrodes, and the particle shape can be confirmed.

  That is, the ink jet recording apparatus head according to the present invention includes a base plate having a confirmation window for confirming the shape of the ink particles, a detachable nozzle for ejecting ink attached to the first surface of the base plate, and the first surface. A vibration source provided on the (front surface) side for making the ink ejected from the nozzles into particles and a second surface (back surface) opposite to the first surface of the base plate are disposed on the ink. Strobe means that operates when confirming the particle shape. Here, as for the nozzles, a plurality of nozzles having different diameters are all attached at the same position. Further, the confirmation window has a horizontally long shape having a long side in the ink ejection direction, and the length of the long side of the horizontally long region of the confirmation window is the nozzle ejection when printing using a plurality of nozzles. It is characterized in that it is longer than the length from the position where the distance from the outlet to the position where ink is atomized to the position where the distance from the jet outlet to the position where ink is atomized becomes the minimum. In other words, the horizontally long region of the confirmation window indicates the position where the ink is atomized when the nozzle having the largest aperture is used and the position where the ink is atomized when the nozzle having the smallest aperture is used. It is the size to cover.

  Further features of the present invention will become apparent from the best mode for carrying out the present invention and the accompanying drawings.

  According to the print head for an ink jet recording apparatus of the present invention, the shape of the ink particles can be confirmed even when the nozzle fixing position is set to one type regardless of the difference in nozzle diameter.

  The present invention relates to a print head for an ink jet recording apparatus having a window for confirming the shape of ink particles, and prevents misassembly by keeping the nozzle mounting position constant regardless of the type of nozzle diameter of the nozzle that performs ink ejection. The present invention relates to a print head that enables stable printing and can confirm the shape of ink particles reliably.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be noted that this embodiment is merely an example for realizing the present invention, and does not limit the technical scope of the present invention. In each drawing, the same reference numerals are assigned to common components.

<Configuration of print head>
1 and 2 are diagrams showing a schematic configuration of a print head for an ink jet recording apparatus according to an embodiment of the present invention. FIG. 1 is a diagram illustrating a state in which one nozzle (for example, a nozzle having the smallest nozzle diameter, that is, the nozzle having the shortest distance from the ink ejection port of the nozzle to the ink particle formation) is mounted on the print head. FIG. 2 is a diagram illustrating a state when another nozzle (for example, the nozzle having the largest nozzle diameter, that is, the nozzle having the longest distance from the ink ejection port of the nozzle to the ink particle formation) is mounted on the print head.

  FIG. 1 is a partial view of the print head cum 3, and a length L 3 that allows light from a strobe (LED: not shown) to pass through the same range as the difference in distance from the ink ejection port 5 to the location 8 where particles are formed. A base plate 2 having a particle confirmation window 1 with

  The print head end face 4 is used as a reference plane, and the ink ejection port 5 is located at a distance L1 from the reference plane. The ink is pumped from the main body, supplied to the nozzle, and ejected from the ink ejection port 5 to become the ink column 6. Appropriate vibration is periodically applied to the ink column 6 by the vibration wall, and ink particles 8 are formed at a position L2 away from the ink ejection port 5 in the charging electrode 7.

  FIG. 2 is a partial view of the print head cum 3 in which another nozzle diameter is mounted on the nozzle diameter of FIG. 1 as described above.

  In FIG. 2, the position of the ink jet outlet 9 (which uses a different reference number because it is a nozzle different from the nozzle of FIG. 1) is the distance L1 from the same reference surface 4 as in FIG. It is set at a distant position. The ink is pumped from the main body, supplied to the nozzle, and ejected from the ink ejection port 9 to become the ink column 10. The ink column 10 is periodically given appropriate vibration from the excitation wall and becomes ink particles 12 in the charging electrode 11. However, since the nozzle diameter of FIG. 2 is different from that of FIG. 1, the pressure for atomizing the ink and the optimum condition of vibration applied from the vibration wall change, and the ink particle is L2 (in the case of FIG. 1). The ink particles 12 are formed at a position L4 farther than the distance L4.

  As described above, it is necessary to give an appropriate vibration to make the ink particles. When the amount of vibration is small or large, the ink does not form particles or generates satellites. The generated satellite cannot give normal charge to the ink particles, and the ink particles cannot be attached to a desired position, thereby disturbing printing.

  As a guideline for determining whether or not the ink particles are optimal, the ink particle shape is confirmed (visually). As a confirmation method, a strobe mechanism (LED) disposed on the back side of the confirmation window 1 provided on the base plate 2 is caused to emit light in synchronization with the frequency of the vibration source provided on the nozzle. The base plate 2 is provided with a particle confirmation window 1 having a secret (seal) property with the base plate 2 in order to transmit strobe light from the back side of the base plate to the front side of the base plate. We are confirming.

  In this embodiment, the length L3 of the particle confirmation window 1 is the same as that of the conventional confirmation window (see FIGS. 3 to 5) by the difference length (ΔL) between L4 shown in FIG. 2 and L2 shown in FIG. ) Is longer than That is, the confirmation window 1 has a horizontally long shape (for example, a rectangle, an ellipse, or an ellipse) having a long side in the ink ejection direction, and the length L3 of the long side is determined from the ink ejection port of the nozzle. The shortest distance is the length that covers the longest position (included in the window area). Accordingly, the confirmation window 1 is configured to be able to confirm both the particles of FIG. 1 and the particles of FIG. 2 at the same nozzle fixed position even when the positions of particle formation differ due to the difference in nozzle diameter.

<Configuration of Comparative Example: In Comparison with the Present Invention>
3 to 5 are diagrams showing a schematic configuration of a conventional print head for an ink jet recording apparatus. These configurations are shown for comparison with the present embodiment.

  FIG. 3 is a view in which the nozzle having the nozzle diameter shown in FIG.

  The particle confirmation window 14 has a structure in which the light of the strobe can be transmitted only within a range of a length L5 shorter than the difference in the distance from the ink outlet to the place where the particles are formed due to the difference in nozzle diameter. In FIG. 3, as in FIG. 1, the print head end face 4 is used as a reference plane, and the ink jet nozzle 5 is located at a distance L1 from the reference plane. The ink is pumped from the main body, supplied to the nozzle, and ejected from the ink ejection port 5 to become the ink column 6. The ink column 6 is periodically given an appropriate vibration from the vibration wall, and becomes ink particles 8 at a position separated from the ink ejection port 5 in the charging electrode 7 by L2.

  FIG. 4 is a partial view of the print head cum 13 on which nozzles having a nozzle diameter different from the nozzle diameter of FIG. 3 are mounted. 4, the print head end face 4 is set as a reference plane, and the position of the ink ejection port 9 is set to a position separated by the same distance L1 from the reference plane 4 as in FIG. is doing. The ink is pumped from the main body, supplied to the nozzle, and ejected from the ink ejection port 9 to become the ink column 10. The ink column 10 is periodically given appropriate vibration from the excitation wall and becomes ink particles 12 in the charging electrode 11. However, the pressure for atomizing ink and the optimum conditions for vibration applied from the vibration wall change depending on the nozzle diameter, and the ink column 10 becomes the ink particles 12 at a distance L4 far from the distance L2.

  The length L5 of the particle confirmation window 14 is equal to the length of the difference between L4 shown in FIGS. 2 and 4 and L2 shown in FIGS. 1 and 3 in comparison with the length L3 of the confirmation window 1 of the present embodiment. It ’s getting shorter. Therefore, when the nozzle installation position is the same (fixed) as in the present embodiment, the position where particles are formed differs depending on the difference in nozzle diameter, so in the case of FIG. 3, the particles can be confirmed. In the case of 4, particles cannot be confirmed.

  For this reason, in the conventional configuration, as shown in the print head cum 16 of FIG. 5, if the nozzle diameter is different, the nozzle mounting position is shifted so that the particles of FIG. 4 can be confirmed. As shown in FIG. 5, the print head end face 4 is used as a reference plane, and the ink jet nozzle 5 is located at a distance L6 from the reference plane. In the conventional print head, the nozzle mounting position is shifted from the reference plane with the print head end face 4 as the reference plane by the length of the difference between L4 shown in FIGS. 2 and 4 and L2 shown in FIGS. Corresponded to various bugs.

  Such correspondence has caused the above-mentioned problems (see [Problems to be Solved by the Invention]), so that the present invention reliably confirms ink particles even when the nozzle mounting position is fixed. The confirmation window 1 having such a configuration is adopted.

<Summary>
In the inkjet recording apparatus print head according to the present embodiment, even if the nozzle diameters are different, all of the plurality of types of nozzles are attached to the same position. The confirmation window has a horizontally long shape (ellipse, oval, rectangle, etc.) having a long side in the ink ejection direction. The length of the long side of the horizontally long region of the confirmation window is a plurality of nozzles. When printing using, the length from the position where the distance from the nozzle outlet to the position where ink is atomized to the position where the distance from the outlet to the position where ink is atomized is the minimum It is characterized by being longer than that. In other words, the horizontally long region of the confirmation window indicates the position where the ink is atomized when the nozzle having the largest aperture is used and the position where the ink is atomized when the nozzle having the smallest aperture is used. It is the size to cover. In other words, the length (L3) of the particle confirmation window is L4 (the maximum value of the distance at which ink is made into particles) and L2 (the ink is dispersed) compared to the conventional circular confirmation window (FIGS. 3 to 5). It is longer by the length of the difference from the minimum particle distance). As a result, it is possible to cope with multiple nozzle diameters even if the nozzle fixing position is one place, and when removing and reassembling the nozzle during maintenance work, it eliminates the cause of misassembly of the nozzle fixing position and improves maintainability. Can be made. Even if the nozzle arrangement position is fixed, the ink particle shape can be reliably confirmed from the confirmation window.

1 is a partial view of a print head for an ink jet recording apparatus according to an embodiment of the present invention. FIG. FIG. 2 is a partial view of a print head for an ink jet recording apparatus according to an embodiment of the present invention, on which a nozzle having a nozzle diameter different from that of FIG. 1 is mounted. FIG. 6 is a partial view of a print head of a conventional ink jet recording apparatus. FIG. 4 is a partial view of a print head of a conventional ink jet recording apparatus equipped with a nozzle having a nozzle diameter different from that of FIG. 3. FIG. 5 is a partial view of a print head for explaining a conventional countermeasure when a nozzle having a different nozzle diameter is mounted with respect to FIG. 4.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Particle confirmation window, 2 ... Base board, 3 ... Print head kumi, 4 ... Print head end surface, 5 ... Ink ejection port, 6 ... Ink column, 7 ... Charging Electrode, 8 ... Ink particle, 9 ... Ink ejection port, 10 ... Ink column, 11 ... Charging electrode, 12 ... Ink particle, 13 ... Print head kumi, 14 ... Particle Confirmation window, 15 ... print head kumi, 16 ... print head kumi

Claims (2)

A base plate having a confirmation window for confirming the shape of the ink particles;
A detachable nozzle for ejecting ink attached to the first surface of the base plate;
A vibration source for forming particles of ink ejected from the nozzle provided on the first surface side;
A strobe unit disposed on a second surface, which is a surface opposite to the first surface of the base plate, and operating when confirming the shape of the ink particles,
A plurality of nozzles with different diameters are all attached at the same position,
The confirmation window has a horizontally long shape having a long side in the ink ejection direction,
The length of the long side of the horizontally long region of the confirmation window is determined from the position where the distance from the nozzle outlet to the position where ink is atomized becomes the maximum when printing is performed using the plurality of nozzles. A print head for an ink jet recording apparatus, wherein the print head for an ink jet recording apparatus is longer than a length from a jet outlet to a position where ink is atomized. A base plate having a confirmation window for confirming the shape of the ink particles;
A detachable nozzle for ejecting ink attached to the first surface of the base plate;
A vibration source for forming particles of ink ejected from the nozzle provided on the first surface side;
A strobe unit disposed on a second surface, which is a surface opposite to the first surface of the base plate, and operating when confirming the shape of the ink particles,
A plurality of nozzles with different diameters are all attached at the same position,
The confirmation window has a horizontally long shape having a long side in the ink ejection direction,
The horizontally long region of the confirmation window includes a position where the ink is atomized when the nozzle having the largest aperture is used and a position where the ink is atomized when the nozzle having the smallest aperture is used. A print head for an ink jet recording apparatus, characterized in that the print head has a size that covers the cover.

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