JP4377138B2 - Image recording device - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to an image recording apparatus, and more particularly to an image recording apparatus in which a plurality of heads are mounted on a carriage.
[0002]
[Patent Document 1]
Japanese Patent Laid-Open No. 7-53082
[Prior art]
[Patent Document 1]
Japanese Patent Laid-Open No. 11-58877 [Patent Document 2]
JP 2001-113679 A [Patent Document 3]
Japanese Patent Laid-Open No. 2002-67281 [0004]
For example, an ink jet recording apparatus is known as an image recording apparatus (also referred to as an “image forming apparatus”) such as a printer, a facsimile machine, and a copying apparatus. The ink jet recording apparatus is a sheet from an ink recording head (it is not limited to paper, but means that ink droplets including OHP can be attached, and is also called a recording medium, a recording medium, or recording paper). Ink is discharged to perform recording.
[0005]
As an inkjet head, a piezoelectric actuator such as a piezoelectric element, a thermal actuator that uses a phase change due to liquid film boiling using an electrothermal transducer such as a heating resistor, a shape memory alloy actuator that uses a metal phase change due to a temperature change, 2. Description of the Related Art An electrostatic actuator using an electrostatic force or the like is known as an energy generating unit for ejecting ink.
[0006]
By the way, in the case of a shuttle type recording apparatus in which a plurality of heads are mounted on a carriage in an ink jet recording apparatus, if there is a variation in the positioning accuracy of the heads relative to the carriage, the ink droplet landing positions from the respective heads shift and superimpose color ink droplets. As a result, the image quality is degraded.
[0007]
Therefore, as described in, for example, [Patent Document 1] to [Patent Document 3], a head position adjusting means with respect to the carriage is provided.
[0008]
[Problems to be solved by the invention]
However, the conventional head position adjustment mechanism as described in [Patent Document 1] to [Patent Document 3] has a complicated structure, and particularly occurs when fixing to the carriage with screws. There is a problem that positional accuracy is reduced by torque.
[0009]
SUMMARY An advantage of some aspects of the invention is that it provides an image recording apparatus that can easily fix a head to a carriage with a simple configuration with high accuracy.
[0010]
[Means for Solving the Problems]
In order to solve the above problems, an image recording apparatus according to the present invention provides:
In an image recording apparatus having a plurality of heads mounted on a carriage,
A reference pin with which a side surface of one end of the head can contact,
A pressing member that urges and presses a side surface of one end of the head against the reference pin ;
A pressing member that biases the upper surface of one end of the head toward the carriage body;
An adhesive member for fixing the other end of the head to the carriage body,
The bonding member and the carriage body are fixed with an adhesive.
[0011]
Here, the carriage has an opening for projecting the nozzle surface of the head downward, and a mounting surface for mounting the lower surface of the head around the opening. The reference pins and the bonding surfaces of the bonding members can be used. Further, the distance between the surface of the head facing the recording medium and the recording medium can be defined regardless of the bonding member. In addition, there may be a space that does not exceed 1 mm between the carriage body and the bonding member.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a configuration diagram illustrating the overall configuration of an ink jet recording apparatus as an image recording apparatus according to the present invention, and FIG. 2 is a plan view illustrating a main part of the recording apparatus.
[0013]
In this ink jet recording apparatus, a carriage 3 is slidably held in a main scanning direction by a guide rod 1 and a stay 2 which are guide members horizontally mounted on left and right side plates (not shown), and a main scanning motor (not shown) is used in FIG. Move and scan in the direction of the arrow.
[0014]
The carriage 3 is provided with a recording head 4 composed of four ink jet heads that eject ink droplets of yellow (Y), cyan (C), magenta (M), and black (Bk), and a plurality of ink ejection openings. They are arranged in a direction crossing the main scanning direction, and are mounted with the ink droplet ejection direction facing downward. The details of the mounting structure of the head 4 to the carriage 3 will be described later.
[0015]
As the ink jet head constituting the recording head 4, a piezoelectric actuator such as a piezoelectric element, a thermal actuator that uses a phase change caused by film boiling of a liquid using an electrothermal transducer such as a heating resistor, and a metal phase change caused by a temperature change. A shape memory alloy actuator to be used, an electrostatic actuator using an electrostatic force, or the like as an energy generating means for discharging ink can be used.
[0016]
The carriage 3 is also equipped with sub-tanks 5 for each color for supplying ink of each color to the recording head 4. Ink is supplied to the sub tank 5 from a main tank (ink cartridge) through an ink supply tube (not shown).
[0017]
On the other hand, as a paper feeding unit for feeding the paper 12 stacked on the paper stacking unit (pressure plate) 11 such as the paper feeding cassette 10, a half-moon roller (separately feeding the paper 12 one by one from the paper stacking unit 11) The sheet feeding roller 13 and the sheet feeding roller 13 are opposed to each other, and a separation pad 14 made of a material having a large friction coefficient is provided. The separation pad 14 is urged toward the sheet feeding roller 13 side.
[0018]
As a transport unit for transporting the paper 12 fed from the paper feed unit on the lower side of the recording head 4, a transport belt 21 for electrostatically attracting and transporting the paper 12 and a paper feed unit A counter roller 22 for transporting the paper 12 fed through the guide 15 between the transport belt 21 and the paper 12 fed substantially vertically upward is turned approximately 90 ° and copied onto the transport belt 21. A conveying guide 23 for adjusting the pressure and a tip pressing roller 25 urged toward the conveying belt 21 by a pressing member 24. In addition, a charging roller 26 as a charging unit for charging the surface of the transport belt 21 is provided. A pressing roller 30 is provided at the tip of the pressing member 24.
[0019]
Here, the conveyance belt 21 is an endless belt, and is configured to be wound around the conveyance roller 27 and the tension roller 28 and to circulate in the belt conveyance direction (FIG. 2). The conveyor belt 21 is a surface layer that is a sheet adsorbing surface formed of a resin material having a pure thickness of about 40 μm that is not subjected to resistance control, such as ETFE pure material, and resistance control by carbon is performed using the same material as the surface layer. It has a back layer (medium resistance layer, ground layer).
[0020]
The charging roller 26 is disposed so as to contact the surface layer of the conveyor belt 21 and rotate following the rotation of the conveyor belt 21, and applies 2.5N to both ends of the shaft as a pressing force. The conveyance roller 27 also serves as the above-described earth roller, and is in contact with the middle resistance layer (back layer) of the conveyance belt 21 and is grounded.
[0021]
In addition, a guide member 31 is disposed on the back side of the conveyance belt 21 so as to correspond to a printing area by the recording head 4. Both ends of the guide member 31 in the main scanning direction are held between frame members 35 that hold the conveying roller 22, the tension roller 28, and the like.
[0022]
The upper surface of the guide member 31 protrudes closer to the recording head 4 than the tangent line of the two rollers (the conveyance roller 27 and the tension roller 28) that support the conveyance belt 21. Thereby, the conveyor belt 21 is pushed up and guided by the upper surface of the guide member 31 in the printing region.
[0023]
Further, a separation claw 41 serving as a separation mechanism for separating the paper 12 from the transport belt 21 is disposed in contact with the transport belt 21 as a paper discharge unit for discharging the paper 12 recorded by the recording head 4. A paper discharge roller 42 and a paper discharge roller 43 are arranged on the downstream side of the separation claw 41, and a paper discharge tray 44 for stocking the paper 12 to be discharged is further provided on the downstream side.
[0024]
A double-sided paper feeding unit 51 is detachably attached to the apparatus main body. The double-sided paper feeding unit 51 takes in the paper 12 returned by the reverse rotation of the transport belt 21, reverses it, and feeds it again between the counter roller 22 and the transport belt 21.
[0025]
In the ink jet recording apparatus configured as described above, the paper 12 is separated and fed one by one from the paper feed unit, and the paper 12 fed substantially vertically upward is guided by the guide 15, and includes the transport belt 21 and the counter roller 22. The leading end is guided by the conveying guide 23 and pressed against the conveying belt 21 by the leading end pressing roller 25, and the conveying direction is changed by approximately 90 °.
[0026]
At this time, a positive output and a negative output are alternately repeated from the high voltage power source to the charging roller 26 by a control circuit (not shown), that is, an alternating voltage is applied, and a charging voltage pattern in which the conveying belt 21 is alternating, In the sub-scanning direction, which is the circumferential direction, plus and minus are alternately charged in a band shape with a predetermined width. When the paper 12 is fed onto the conveyance belt 21 charged alternately with plus and minus, the charge is polarized in the opposite direction to the charge pattern in the paper 12, so that a capacitor connected in parallel is formed. 12 is adsorbed by the conveyance belt 21, and the paper 12 is conveyed in the sub-scanning direction by the circular movement of the conveyance belt 21.
[0027]
Therefore, by driving the recording head 4 according to the image signal while moving the carriage 3, the ink droplets are ejected onto the stopped paper 12 to record one line, and after the paper 12 is conveyed by a predetermined amount, Record the next line. Upon receiving a recording end signal or a signal that the trailing edge of the paper 12 has reached the recording area, the recording operation is finished and the paper 12 is discharged onto the paper discharge tray 44.
[0028]
At this time, since the separation claw 41 faces the paper discharge unit side of the conveyance belt 21, the paper 12 is reliably separated from the conveyance belt 21 and discharged, and is caught and jammed while being adsorbed on the conveyance belt 21. It is prevented.
[0029]
A head mounting structure in the ink jet recording apparatus will be described with reference to FIGS. 3 is an explanatory side view of the main part of the head mounting part of the carriage, FIG. 4 is an explanatory plan view of the main part of the head mounting part of the carriage, FIG. 5 is a perspective explanatory view, and FIG. 6 is viewed from the nozzle surface of the head. It is principal part plane explanatory drawing. Here, only two heads 4 are shown.
[0030]
An adhesive member 51 is provided on one end side of the head 4 in the paper conveyance direction, and the nozzle surface protrudes downward from an opening 3a provided in the carriage body 3A of the head 4, and the head 4 in the paper conveyance direction and the like. By pressing the end side with an elastic pressing member 52 attached to the carriage main body 3A and bonding the adhesive member 51 on the other end side in the sheet conveying direction and the carriage main body 3A with an adhesive 53, A head 4 is fixed to the carriage 3.
[0031]
The bonding member 51 of the head 4 is formed with a round hole 54 as a means capable of connecting an adjusting jig. Further, the bonding member 51 is bent into a shape in which a space of 1 mm or less (interval a in FIG. 3) is formed between the bonding member 51 and the inner surface of the carriage body 3 when the head is attached. The bonding member 51 has one end fixed to the head 4 and the other end protruding outward from an opening 3b formed in the carriage body 3A. In other words, the distance b from the outer end surface of the carriage body 3A to the round hole 54 is secured, and the distance b is a length that allows the adjustment jig to be connected to the round hole 54 of the bonding member 51 outside the carriage body 3. Is set.
[0032]
On the other hand, on the lower inner surface side of the carriage body 3A, as shown in FIG. 4, a reference pin 55 that can contact the side surface on one end side of the head 4 and the side surface on one end side of the head 4 toward the reference pin 55 side. A pressing member 56 made of an elastic member for urging and pressing is provided. The pressing member 56 is fixed to a fixing member 57.
[0033]
The mounting of the head in such a configuration will be described. The mounting accuracy of the head 4 mounted on the carriage 3 is required to be on the order of microns. In this case, as shown in FIG. 6, the nozzle row 4 a of the head 4 is perpendicular to the guide rod 1 and a specific nozzle row of the plurality of heads 4, 4 (positioned at the same position in the main scanning direction). The meaning of the nozzle row of each head is required to be parallel to the guide rod 1.
[0034]
Therefore, one end of the head 4 is inserted between the reference pin 55 and the pressing member 56 of the carriage body A3, and the head 4 is set so that the nozzle surface protrudes from the opening 3a. Then, specific nozzles of the head 4, for example, as shown in FIG. 3, the nozzle fa on the most upstream side and the nozzle la on the most downstream side in the paper conveyance direction are captured by an optical microscope or the like, and the head 4 is finely moved to the position. Is set to a target position, and after setting, the bonding member 51 and the carriage body 3A are bonded and bonded by the adhesive 53. By fixing by adhesive bonding, higher accuracy of mounting accuracy can be obtained.
[0035]
At this time, the head 4 is positioned by inserting the adjusting jig into the round hole 54 of the bonding member 51 of the head 4 and moving the bonding member 51 in the X and Y directions in FIG. 4 while operating the adjusting jig. Can do. By providing the bonding member 51 in the head 4 in this way, the head 4 that increases the manufacturing cost can be reduced, and the cost can be reduced. Further, since the bonding member 51 protrudes outside the carriage body 3A, the position of the head 4 can be adjusted from the outside of the carriage 3, and the adjustment operation becomes easy.
[0036]
Further, it is preferable to use an ultraviolet (UV) curable adhesive as the adhesive 53 for bonding the bonding member 51 and the carriage body 3A. The UV curable adhesive does not advance until it is exposed to ultraviolet rays, so that a time margin can be ensured. Since the curing is accelerated by applying UV rays, it is easy to control. Further, the curable adhesive can be destroyed by applying an instantaneous force in the shear direction, and even when adjustment fails, the adhesive can be easily destroyed and the head 4 can be most utilized without being discarded.
[0037]
Although it is difficult to form the head 4 with a resin member that transmits ultraviolet light, the head 4 and the bonding member 51 can be separated to form the bonding member 51 with a resin member that transmits ultraviolet light. Further, by separating the head 4 and the bonding member 51 as described above, it is possible to remove the bonding member 51 from the carriage 3 without destroying the head 4.
[0038]
Further, when the adhesive 53 is cured, the head 4 exerts a thrust force due to curing condensation, so that the adhesive 53 can move freely by leaving a gap a between the adhesive member 51 and the inner surface of the carriage body 3A. As a result, the thrust force of the head 4 is reduced, so that a higher mounting accuracy can be obtained.
[0039]
Here, the distance between the nozzle surface of the head 4 and the paper as the recording medium is defined by the component accuracy of the head 4 and the carriage 3 and is not affected by the adhesive 53.
[0040]
The image recording apparatus according to the present invention can be applied to a facsimile apparatus, a copying apparatus, a printer / fax / copier multifunction machine, etc., in addition to an ink jet printer. Furthermore, the present invention can also be applied to an image recording apparatus that discharges a liquid other than ink, such as a resist or a DNA sample in the medical field.
[0041]
【The invention's effect】
As described above, according to the image recording apparatus of the present invention, the reference pin with which the side surface of the one end portion of the head can come into contact, and the pressing that urges and presses the side surface of the one end portion of the head against the reference pin . A member, a pressing member that biases the upper surface of one end of the head toward the carriage body, and an adhesive member that fixes the other end of the head to the carriage body. The adhesive member and the carriage body are bonded with an adhesive. Since the configuration is fixed, the head can be fixed to the carriage easily and with high accuracy with a simple configuration.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of an image recording apparatus according to an embodiment of the present invention. FIG. 2 is an explanatory plan view of a main part of the recording apparatus. FIG. 5 is a perspective explanatory view of the main portion of the carriage head mounting portion. FIG. 6 is a perspective explanatory view of the main portion as viewed from the nozzle surface of the head.
DESCRIPTION OF SYMBOLS 3 ... Carriage, 3A ... Carriage main body, 4 ... Recording head, 12 ... Paper, 21 ... Conveyance belt, 26 ... Charging roller, 27 ... Conveyance roller, 28 ... Tension roller, 51 ... Adhesive member, 53 ... Adhesive.

Claims (4)

In an image recording apparatus having a plurality of heads mounted on a carriage,
A reference pin with which a side surface of one end of the head can contact,
A pressing member that urges and presses a side surface of one end of the head against the reference pin ;
A pressing member that biases the upper surface of one end of the head toward the carriage body;
An adhesive member for fixing the other end of the head to the carriage body,
An image recording apparatus, wherein the bonding member and the carriage body are fixed with an adhesive. The image recording apparatus according to claim 1, wherein the carriage includes an opening for projecting a nozzle surface of the head downward, and a mounting surface for mounting a lower surface of the head around the opening. An image recording apparatus comprising: a mounting surface on which the reference pins and the bonding surfaces of the bonding members are provided.   3. The image recording apparatus according to claim 1, wherein a distance between a surface of the head facing the recording medium and the recording medium is defined irrespective of the bonding member. Recording device.   4. The image recording apparatus according to claim 1, wherein there is a space not exceeding 1 mm between the carriage body and the bonding member.

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