JP2011126269A - Inkjet printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet printer equipped with a light irradiation device which can lighten the weight of a carriage, can reduce the exchange frequency for light sources and can simplify a shutter device by using one light source. <P>SOLUTION: The light irradiation device which irradiates a light for fixing photo-fixing ink ejected from an inkjet head is loaded on the carriage which carries the inkjet head to eject the photo-fixing ink to a recording medium. The light irradiation device has the light source which emits the light, a condensing means which condenses the light emitted from the light source, an optical path selecting means which changes an optical path into an arbitrary direction for the condensed light, an optical path controlling means which controls the optical path selecting means, and irradiating means which irradiates the light changed in the optical path on both sides of scan direction of the carriage. The photo-fixing ink ejected to the recording medium is fixed by the light irradiated from the irradiating means. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an ink jet printer that discharges a light fixing ink and fixes it by a light irradiation device.

  Conventionally, an ink jet printer using light fixing ink by a light irradiation device has a light irradiation device mounted on both sides in the scanning direction of the carriage. Patent Document 1 discloses that each light irradiation device is equipped with a light source, and whether or not irradiation is performed is performed by opening and closing a shutter device.

JP 2004-338172 A

  In the prior art, an ink jet printer using light fixing ink by a light irradiation device is equipped with two light irradiation devices, so that the carriage weight increases, and it is necessary to increase the output of an actuator that drives the carriage. Also, there are two light sources that are consumables, and each needs to be replaced when it reaches the end of its life, so the replacement frequency increases. When a shutter device is mounted on each light irradiation device so that the lifetime of the light source is not impaired by repeating the turning on and off, the manufacturing process and cost are increased.

  The present invention provides an ink jet printer including a light irradiation device that can reduce the weight of a carriage, reduce the frequency of light source replacement, and simplify a shutter device by using a single light source.

  A first aspect of the present invention for solving the above-described problems is an ink jet head that ejects light fixing ink onto a recording medium, and light that emits light for fixing the light fixing ink ejected from the ink jet head. A light source that emits the light in an ink jet printer that scans the carriage in a direction that intersects the conveyance direction of the recording medium and forms an image on the recording medium; Condensing means for condensing the light emitted from, an optical path selection means for changing the optical path of the condensed light in an arbitrary direction, an optical path control means for controlling the optical path selection means, and the inkjet head. The optical path of the light coming from the optical path selection means arranged on both sides in the scanning direction of the carriage is bent, and the optical path is placed on the recording medium. Irradiating means for irradiating at least the light source, the condensing means, the optical path selecting means, and the irradiating means mounted on the carriage, and the optical path to the optical fixing ink ejected to the recording medium. An ink jet printer, wherein the light is fixed by irradiating the light through an optical path controlled by a control unit.

  The second aspect of the present invention includes an optical fiber cable between the optical path selection unit and the irradiation unit, and the light emitted from the light source is irradiated from the optical path selection unit through the optical fiber cable. The inkjet printer according to the first aspect, which is incident on the means.

  According to a third aspect of the present invention, the optical fiber cable is divided into a plurality of systems, and the light is irradiated from a plurality of the irradiation means arranged on both sides in the scanning direction of the carriage. The ink jet printer according to the second aspect.

  According to a fourth aspect of the present invention, an ultraviolet curable ink is used as the light fixing ink, and a light source that irradiates light including ultraviolet rays is used as the light source. The inkjet printer according to any one of the first to third aspects, wherein the ink is fixed.

  According to a fifth aspect of the present invention, the infrared light is used by using a light source that irradiates light including infrared light to the light source using an ink that is fixed to the light fixing ink by infrared light. The ink jet printer according to any one of the first to third aspects, wherein the ink is fixed by irradiating the ink.

  According to a sixth aspect of the present invention, in the ink jet printer according to any one of the first to fifth aspects, the light fixing ink is fixed using an LED as the light source. is there.

  According to a seventh aspect of the present invention, there is provided the inkjet printer according to any one of the first to sixth aspects, wherein a mirror that transmits infrared light is used as the optical path selection unit. .

  According to an eighth aspect of the present invention, there is provided a first aspect, a second aspect, a third aspect, or a fourth aspect, wherein a mirror that transmits light other than ultraviolet light is used for the optical path selection means. It is an inkjet printer as described in any one of the aspects.

  According to a ninth aspect of the present invention, there is provided a first aspect, a second aspect, a third aspect, or a fifth aspect, wherein a mirror that transmits light other than infrared light is used for the optical path selection means. It is an inkjet printer as described in any one of aspect.

  According to a tenth aspect of the present invention, from the first aspect, the light source is disposed above the ink jet head, and the optical path selecting means is disposed between the ink jet and the light source. It is an inkjet printer as described in any one of 6th aspect.

  According to an eleventh aspect of the present invention, there is provided a reflecting means for reflecting scattered light among the light between the inkjet head and the optical path selecting means. Inkjet printer.

  By using one light source, the weight of the carriage can be reduced. In addition, by using one light source that is a consumable, the replacement frequency can be reduced and the replacement cost can be reduced. In addition, since the light irradiation can be turned on and off in a simple structure, it is possible to reduce the weight, size, and cost.

FIG. 1 is a configuration diagram of an example of a carriage and a light irradiation device of an inkjet printer according to the present invention. FIG. 2 is a configuration diagram of an example of a light irradiation apparatus using an optical fiber cable. FIG. 3 is a block diagram of a control portion of the light irradiation apparatus. FIG. 4 is a flowchart showing the operation of the light irradiation apparatus.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an example of a configuration diagram of a carriage and a light irradiation device of an ink jet printer according to the present invention.

  As shown in FIG. 1, the ink jet printer of the present embodiment includes an ink jet head 4 that discharges light fixing ink onto a medium 3 on a carriage 1 and a light irradiation device that fixes the light fixing ink landed on the medium 3. 5 is mounted. In the light irradiation device 5, a light source 6 is disposed at the upper center of the carriage, and a condensing unit 7 that efficiently reflects and collects light from the light source 6 is disposed above the light source 6. The carriage 1 ejects light fixing ink from the lower surface of the inkjet head 4 while moving in the scanning direction on the medium 3 along the Y rail 2.

  The condensing means 7 is, for example, a reflector, and preferably an elliptical reflector. The condensing means can also condense using a plurality of mirrors. The light source 6 can be a lamp, LED, or the like. When the LED is used, the light condensing means 7 can be used, but a structure which is not required can be used, and when it is not necessary, the structure can be further simplified.

  Further, by using an ultraviolet irradiation light source for the light source 6, it can be used for an ink jet printer using an ultraviolet curable ink. Moreover, by using an infrared irradiation light source for the light source 6, it can be used for an ink jet printer using ink that is fixed by evaporation of moisture by infrared rays or heat.

  The light from the light source 6 and the light reflected by the condensing means 7 pass through the concave lens 8 positioned below the light source 6 and enter the fly eye lens 9 below. The fly-eye lens 9 is used to eliminate uneven illuminance. As another example, in order to eliminate unevenness in illuminance, the mirror 10, the curved mirror 11, or the light source 6 may be finely oscillated so that the light is uniformly irradiated not only at a fixed position but also within a predetermined range. However, it is necessary to provide a separate vibration device in order to vibrate in this way. Such a configuration can be mounted on the carriage 1 if there is a sufficient volume and weight. If it is desired to make it smaller, it is preferable to control the light irradiated using the concave lens 8 and the fly-eye lens 9.

  The light that has passed through the fly-eye lens 9 is reflected by a mirror 10 that can control the angle. This mirror 10 uses a dichroic mirror, and when it is desired to exclude heat to the medium 3, it is an infrared transmission type, when it is desired to exclude visible light, it transmits visible light, and when it is desired to exclude ultraviolet light harmful to the human body. In this case, a mirror that can reflect light other than the transmitted light, such as an ultraviolet transmission type, is used, and the mirror 10 is selected according to the application. As another aspect, instead of a mirror that reflects light at a desired wavelength, a filter that transmits or blocks only light having a desired wavelength may be disposed in the middle of the optical path as means for selecting light. Furthermore, although these means for selecting light having a desired wavelength may be heated, this heat may be radiated to the outside by a heat radiating means such as a fin or a fan.

  By using the infrared transmission type mirror 10, light that does not include infrared light is irradiated onto the medium 3. Therefore, the influence of heat by infrared light can be eliminated, and for example, deformation of the media 3 due to heat can be prevented. By using visible light transmission type mirror 10, it is possible to irradiate light that does not include visible light from light irradiation device 5, and to protect the eyes of workers around the printer from strong visible light from light source 6, Safety as an inkjet printer is improved. By using the ultraviolet transmissive mirror 10, the light irradiation device 5 emits light that does not contain ultraviolet light, so that it is possible to eliminate the adverse effects of the ultraviolet light on the human body.

  The curved mirror 11 is arranged on one side of the carriage 1 in the scanning direction so that the light from the mirror 10 can be reflected and irradiated onto the medium 3. A concave mirror is used as the curved mirror 11, and the shape and angle of the curved mirror 11 are determined so that the light reflected by the curved mirror 11 can be irradiated on the medium 3 in a desired position and range in parallel. By changing the angle of the mirror 10, it is possible to irradiate the light by being reflected by another curved mirror 11 arranged in the same manner on the opposite side of the carriage 3 in the scanning direction. By using this method, a conventional irradiator including a light source is arranged on both sides in the scanning direction of the carriage and alternately irradiated. However, it is possible to irradiate alternately with one light source. The mirrors 11 may be arranged on at least both sides in the scanning direction, and each side mirror may be divided into a plurality of parts. By using a plurality of mirrors on each side, the irradiation position can be set finely.

  The angle of the mirror 10 is controlled using a stepping motor. In addition to the stepping motor, a DC motor can be used. In this case, feedback control for controlling the rotation speed is necessary. By setting the angle of the mirror 10 so that the light reflected by the mirror 10 does not enter either curved mirror 11, the medium 3 can be prevented from being irradiated with light. This eliminates the need for the shutter mechanism that each of the illuminators on both sides in the scanning direction of the conventional carriage has.

  With respect to the arrangement of the light source 6 and the mirror 10, the light source 6 is arranged as close to the Y rail 2 as possible in the center of the carriage 3 so that the left and right irradiation ranges can be easily equalized, and the weight balance of the carriage is increased. Is also optimal. Even when an optical fiber cable is used in the middle of the optical path, the same arrangement of the light sources is preferable in order to equalize the light energy loss of the optical fiber cable and equalize the left and right irradiation light energy. In addition, it is desirable to reduce the cost by arranging the optical fiber cable at the shortest distance. Similarly, the angle-controlled mirror 10 is also arranged in the center of the left and right curved mirrors 11, that is, in the center of the carriage 3, so that the left and right light energy loss is equal to the left and right irradiation ranges, and the weight balance of the carriage is improved. Equilibrium is also effective.

  The light source 6 generates light and generates heat. Ink ejected by the ink jet head 4 changes in characteristics such as viscosity depending on temperature, and if the temperature becomes too high, it causes ejection failure. Therefore, the ink jet head 4 and the light source 6 are arranged at positions separated from each other. For example, the mirror 10 is disposed above the inkjet head 4, the light source 6 is disposed further above, and the concave lens 8 and the fly-eye lens 9 are disposed between the mirror 10 and the light source 6. Further, in order to reflect the scattered light, it is desirable to arrange a reflecting means such as a mirror that reflects light or a mirror-finished metal plate between the inkjet head 4 and the mirror 10. Furthermore, it is preferable to arrange a heat insulating material between the reflecting means and the inkjet head 4 so that heat transfer is difficult. By preventing the heat generated by the light source 6 from being transferred to the inkjet head 4 and increasing the ink temperature, the influence on the image quality can be prevented.

  FIG. 2 is an example of a configuration diagram of a light irradiation apparatus using an optical fiber cable. The positional relationship between the light source 6 and the condensing means 7 is the same as in FIG. The light emitted from the light source 6 and the light condensed by the condensing means 7 pass through the condensing lens 12 and enter an entrance portion which is an end portion on one side of the optical fiber cable 13. Since the optical fiber cable 13 is a flexible cable, the light source 6 and the light condensing means 7 can be arranged at arbitrary locations. However, since the optical fiber cable 13 is expensive, it is necessary to make it as short as possible, and it is desirable to arrange the light source 6 and the light condensing means 7 at the center upper part of the carriage. The exit side of the optical fiber cable 13 divides the fiber cable into at least two parts in the middle of the cable. The divided optical fiber cable 13 is composed of a bundle of a plurality of fibers, and the fibers on the exit side are connected at equal intervals in the longitudinal direction of the flat side of the two plano-convex cylindrical lenses 14, respectively. By doing so, the light irradiated from the exit portion of the optical fiber cable 13 divided into at least two can be irradiated to a desired irradiation range through the two cylindrical lenses 14 arranged on both sides in the scanning direction of the carriage. .

  Next, the operation when the optical path is changed by the mirror will be described with reference to FIGS. FIG. 3 is a block diagram of a control portion of the light irradiation apparatus. FIG. 4 is a flowchart showing the operation of the light irradiation apparatus.

  A ROM 101, a RAM 102, and a stepping motor drive circuit 103 are connected to the control circuit 100. A stepping motor 104 is connected to the stepping motor drive circuit 103.

The ROM 101 stores a program, and the control circuit 100 operates according to this program. In addition to the program, the ROM 101 stores various setting values such as initial setting values used for control. The RAM 102 is used as a work area for temporary storage of data and calculation. A mirror is connected to the stepping motor 104, and the mirror rotates according to the angle of the axis of the stepping motor, so that the optical path can be changed. That is, the optical path change control can be performed by controlling the rotation of the stepping motor 104. The stepping motor drive circuit 103 is driven so that the stepping motor 104 rotates the number of steps specified by the control circuit 100.
The mirror angle control process starts (step S1).

A mirror angle is instructed to instruct how many angles the mirror is to be moved with respect to a reference position in advance (step S2). The indication of the mirror angle is determined, for example, by determining whether light is emitted from the rear irradiator or the front irradiator with respect to the carriage traveling direction. Since the position of the irradiator and the position on the light source side are fixed, the angles of the mirrors necessary for changing the optical path in each direction are determined in advance, and each angle is stored in the ROM 101 in advance. Therefore, as long as irradiating from which irradiator is determined, it is the same as instructing the mirror angle. Further, the angle of the mirror can take not only two values but also a plurality of stages. Similarly, the angle is stored in the ROM. When the mirror angle is instructed, the process proceeds to step S3.
The angle difference between the designated mirror angles with respect to the current mirror angle is calculated (step S3).

  Next, the number of steps of the stepping motor 104 for rotating the calculated angle difference mirror is calculated (step S4). Since it is known in advance how many times the mirror rotates when the stepping motor 104 rotates one step, the number of steps to rotate is calculated from the angle difference.

  Next, a command is output to the stepping motor drive circuit 103 so as to drive the stepping motors 104 for the calculated number of steps, and the stepping motor 104 is driven (step S5). Next, the process of rotating the mirror ends (step S6).

  In this way, by controlling the stepping motor 104, the angle of the mirror 10 can be controlled according to the program stored in the ROM 101. The irradiation means on one side in the scanning direction of the carriage 1 is irradiated with ultraviolet rays, the other side is irradiated, neither is irradiated, or the mirror 10 is irradiated from both sides depending on the angle. It can also be controlled.

  When an LED is used as the light source, ON / OFF control of the LED can control ON / OFF of light irradiation when light is not irradiated from either irradiation means. When a lamp is used as the light source, the mirror is controlled to a position where light is not irradiated from either side of the irradiation means after the lamp output is not turned off and is set to a level lower than the predetermined level in the control range, preferably the minimum level. To do. This is because heat generation can be suppressed by reducing the lamp output. In this case, it is preferable that light is shielded from the light path from the light source 6 to the mirror 10 so that light does not leak, and that the shield has heat radiation means. This is to dissipate the heat generated by lamp irradiation to the outside.

  The present invention can be used for an ink jet printer using a light fixing ink.

DESCRIPTION OF SYMBOLS 1 Carriage 2 Y rail 3 Media 4 Inkjet head 5 Light irradiation apparatus 6 Light source 7 Condensing means 8 Concave lens 9 Fly eye lens 10 Mirror 11 Curved mirror 12 Condensing lens 13 Optical fiber cable 14 Cylindrical lens 100 Control circuit 101 ROM
102 RAM
103 Stepping motor drive circuit 104 Stepping motor

Claims (11)

  A carriage having an inkjet head for ejecting light fixing ink onto a recording medium and a light irradiation device for irradiating light for fixing the light fixing ink ejected from the inkjet head; In an inkjet printer that scans in a direction intersecting with a medium conveyance direction and forms an image on the recording medium, a light source that emits the light, a condensing unit that condenses the light emitted from the light source, An optical path selection means for changing the optical path of the emitted light in an arbitrary direction, an optical path control means for controlling the optical path selection means, and the optical path selection means arranged on both sides in the scanning direction of the carriage across the inkjet head. And an irradiation means for irradiating the light onto the recording medium by bending an optical path of the light coming from the carriage. At least the light source, the condensing unit, the optical path selection unit, and the irradiation unit are mounted, and the light fixing ink ejected onto the recording medium is irradiated with the light through the optical path controlled by the optical path control unit. An ink jet printer characterized by fixing.   An optical fiber cable is provided between the optical path selection unit and the irradiation unit, and the light emitted from the light source is incident on the irradiation unit from the optical path selection unit through the optical fiber cable. The inkjet printer according to claim 1.   The inkjet printer according to claim 2, wherein the optical fiber cable is divided into a plurality of systems, and the light is irradiated from a plurality of the irradiation units arranged on both sides in the scanning direction of the carriage.   The ultraviolet curable ink is used as the light fixing ink, and a light source that irradiates light including ultraviolet rays is used as the light source, whereby the ultraviolet curable ink is fixed by irradiating the ultraviolet light. The ink jet printer according to claim 3.   The ink is fixed by irradiating the infrared light to the light fixing ink by using an ink that is fixed by infrared light and using a light source that irradiates the light source with light including infrared light. The inkjet printer according to any one of claims 1 to 3.   The inkjet printer according to any one of claims 1 to 5, wherein the light fixing ink is fixed using an LED as the light source.   The inkjet printer according to any one of claims 1 to 6, wherein a mirror that transmits infrared light is used as the optical path selection unit.   The inkjet printer according to claim 1, wherein a mirror that transmits light other than ultraviolet light is used as the optical path selection unit.   The ink jet printer according to claim 1, wherein a mirror that transmits light other than infrared light is used for the optical path selection unit.   The inkjet according to any one of claims 1 to 6, wherein the light source is disposed above the inkjet head, and the optical path selection unit is disposed between the inkjet and the light source. printer.   The inkjet printer according to claim 10, further comprising a reflection unit that reflects scattered light of the light between the inkjet head and the optical path selection unit.

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