JP2008155621A - Liquid discharge recording head and liquid discharge recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the landing position accuracy of fine discharge liquid droplets by reducing inflow air flow inflowing the area between an inkjet recording head and a paper by a carriage scanning. <P>SOLUTION: An inflow air flow discharge flow path 11 is arranged in the inkjet recording head 1 and a protrusion a21 is arranged in an exit portion of the inflow air flow discharge flow path 11 to reduce the inflow air flow 12 occurring between the head 1 and the paper 7 when the inkjet recording head 1 scans on a liquid droplet receiving member 7 (paper) in an Xa direction. The inflow air flow discharge flow path 11 is arranged in the upstream side of a liquid discharge portion 2 relative to the inflow air flow 12. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a liquid discharge recording head and a liquid discharge recording apparatus that perform recording with a liquid discharged from a liquid discharge section by moving a liquid discharge section that discharges liquid relative to a recording medium.

  In recent years, with the aim of further high-resolution liquid discharge recording technology, the development of technology to discharge at a higher speed while reducing the size of the impact dot by making the discharge liquid into a micro liquid (less than 1 picoliter) has been actively conducted. ing.

  In a general ink jet printer, an image is formed by alternately repeating conveyance of a recording sheet and scanning a recording head that discharges ink droplets on the sheet in a direction crossing the recording sheet conveyance direction. In such an ink jet printer, when the above-described minute liquid is ejected at a high speed, the landing positions on the recording medium where the infinite number of minute liquids ejected from the ejection orifices land on the recording medium such as a sheet are set to respective predetermined positions. It is important to develop technology to prevent deviation from the landing position.

  The following factors can be cited as the cause of the irregular landing that deviates from the predetermined landing position of the minute liquid. For example, the structure of the nozzle that discharges the liquid, the ink adhered to the head surface where the liquid discharge port is open, the vibration / tilt of the carriage on which the ink jet recording head is mounted, and between the head and paper (liquid receiving part) Air flow, deflection of the paper surface (recording medium), and the like.

  In particular, the liquid landing position deviation caused by the air flow between the head and the paper (recording medium) is usually referred to as “an error due to an air current” (hereinafter referred to as an air current error). For example, there is a phenomenon in which the liquid ejected from the ejection port at the end of the ejection port array for ejecting liquid in the recording head is distorted toward the inside of the ejection port array due to the airflow. When an inner deviation occurs at the end of the ejection port array, a gap (joint streak) is formed in which liquid does not land at the joint of each recording scan when a plurality of lines are recorded by a plurality of carriage scans. It becomes. For this reason, technological development for improving the above-described inner twist has been actively performed (see, for example, Patent Documents 1 and 2). It has been found that such an “air flow” that causes the inner twist at the end of the discharge port array is an air flow generated by the discharge liquid itself (hereinafter referred to as self-air flow).

  Furthermore, in addition to the self-airflow, there is an airflow (hereinafter referred to as an inflow airflow) that flows into the area between the inkjet recording head and the paper (recording medium) by carriage scanning as an airflow that affects the airflow deviation. When an image is formed by landing a minute liquid on paper (recording medium), since the landing dots are small, it is necessary to increase the carriage scanning speed to perform high-speed recording in order to shorten the print output time. At that time, the inflow airflow flowing into the area between the ink jet recording head and the paper (recording medium) by the carriage scanning relatively increases. When this inflow air current becomes strong, the mass of a minute liquid is small, so that the flight trajectory of the liquid is greatly affected. And when this inflow air current becomes large, it changes greatly from the inner side deviation at the end part of the discharge port array, so that the center of the discharge port array is larger than the end part of the discharge port array toward the center of the discharge port array. . When the inner deviation occurs in the central portion of the ejection port array, a phenomenon occurs in which the central portion of the recording scan (image during recording in the row direction) becomes dark.

  However, in the conventional technique, no consideration is given to the inner twist at the center of the discharge port array. For example, in the current situation where the number of ejection port arrays is increased corresponding to the increase in the number of colors used, a uniform electric field is applied to all the micro ejection liquids existing in the area between the ink jet recording head and the paper (recording medium). It is difficult to multiply. Further, it is difficult to improve the inner side deviation of the central portion of the discharge port array, which is a mechanism for correcting the inner side deviation of the end portion of the discharge port array and has a larger amount of deflection than the inner side deviation of the end portion of the discharge port row.

On the other hand, in order to remove ink mist in a printer, there is an ink jet head in which a plurality of ejection port arrays are arranged in parallel and an ink suction port is provided at the end in the parallel direction (see Patent Document 3). However, it is not intended to eliminate the inner twist at the center of the discharge port array as described above. Further, a negative pressure generating means is provided in the printer for sucking the floating ink, and the negative pressure suction means allows the moving space volume between the head and the paper during head scanning through the tube from the ink suction port of the head. When a flow rate corresponding to (mm ³ / sec) is sucked, it is configured. For this purpose, a configuration in which negative pressure generating means is provided in a printer other than the head and the head that moves by scanning and the negative pressure generating means are connected by a tube is specially provided.
JP 2002-103626 A JP 2002-337318 A JP 2000-255083 A

  An object of the present invention is to provide a liquid discharge recording head and a liquid discharge recording apparatus that can solve at least one of the problems of the background art. One of the purposes is that when recording is performed during the reciprocating movement of the liquid ejection recording head, the inflow relatively flows into the area between the liquid ejection recording head and the recording medium as the carriage scans. It is to improve the landing position accuracy of the minute discharge liquid by suppressing the air flow.

  One aspect of the present invention is a liquid discharge recording head having a liquid discharge portion for discharging a liquid, wherein the first surface on which the liquid discharge portion is provided and the side surface on which the first surface is disposed. A housing having a second surface disposed on a different side surface, a first opening provided between the liquid ejection section and an edge of the first surface, provided on the second surface, A protrusion provided on the second surface between the second opening communicating with the first opening, the end of the second surface corresponding to the end of the first surface, and the second opening. And providing a head for liquid discharge recording.

  According to another aspect of the present invention, a liquid discharge recording head having a liquid discharge recording head having a liquid discharge portion for discharging liquid onto a recording medium and performing discharge recording while scanning the liquid discharge recording head is provided. A first surface on which the liquid ejection unit is provided, and a second surface disposed on a side different from the side in the scanning direction of the liquid ejection recording head on which the first surface is disposed; A housing of the liquid ejection recording head having: a first opening provided in the housing between the liquid ejection portion and an edge of the first surface; and the second surface of the housing. A second opening between the second opening, the second opening communicating with the first opening, the edge of the second surface corresponding to the edge of the first surface, and the second opening. A projection that is provided; and a scanning guide that scans the recording medium with the liquid ejection recording head, the first opening Wherein arranged in the scanning direction in front of the time of recording execution of the liquid discharge portion, the protrusion is to provide a liquid discharge recording apparatus is arranged in the scanning direction in front of the second opening.

  According to another aspect of the present invention, there is provided a carriage on which a liquid discharge recording head having a liquid discharge portion for discharging liquid onto a recording medium is mounted, and the carriage on which the liquid discharge recording head is mounted. A liquid discharge recording apparatus that performs discharge recording while scanning the liquid, and includes a first surface facing the recording medium together with the liquid discharge portion, and a side in the scanning direction of the liquid discharge recording head on which the first surface is arranged A carriage housing having a second surface disposed on a side different from the side of the carriage, and the housing disposed between the portion on which the liquid ejection unit is disposed and the edge of the first surface. A first opening, a second opening provided in the second surface of the housing and communicating with the first opening, an edge of the second surface corresponding to the edge of the first surface, A projection provided on the second surface between the second opening and the carriage in front A scanning guide section that scans the recording medium, wherein the first opening is disposed in front of the portion where the liquid ejection section is disposed in the scanning direction when recording is performed, and the protrusion is the second section. An object of the present invention is to provide a liquid discharge recording apparatus arranged in front of the opening in the scanning direction.

  According to the present invention, it is possible to improve the landing position accuracy of a minute discharge liquid.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, suitable embodiments of the invention will be described with reference to the drawings. The embodiments described below are appropriate specific examples of the present invention, and thus various technically preferable limitations are attached. However, as long as the idea of the present invention is met, the present invention is not limited to the embodiments and other specific shapes described below.

  The idea of the present invention is simply a mist-like liquid generated in a space between the surface where the discharge port of the liquid discharge recording head is opened and the recording medium facing the surface. It does not remove it from the space. The basic idea of the idea is to eliminate the airflow itself that flows into the space where the discharge port and the recording medium face in order to suppress the airflow fluctuation caused by the self-airflow generated in the space, , There are also some notable configurations for its exclusion. The details are described below.

(Embodiment 1)
FIG. 1 is a perspective view showing a configuration of an ink jet recording head (liquid discharge recording head) that is Embodiment 1 of the present invention, and FIG. 2 is a perspective view showing a basic configuration of an ink jet recording apparatus equipped with the recording head of Embodiment 1. is there.

  The ink jet recording apparatus 4 shown in FIG. 2 is mounted on the ink jet recording head 1 shown in FIG. 1 and a carriage 6 that can hold it, and can perform reciprocating scanning in a predetermined direction (for example, the Xa direction in the figure). A necessary guide member 5 is provided. In a normal ink jet recording apparatus, the above-mentioned predetermined direction is a direction that intersects or is orthogonal to the transport direction in the recording region of the sheet material that is a recording medium.

  The scanning guide unit that scans the ink jet recording head 1 in a predetermined direction is not shown, but includes, for example, a timing belt that is driven by a motor. Further, the ink jet recording head 1 includes a liquid discharge unit 2 in which a discharge port array for discharging ink droplets is disposed, and a liquid holding unit (ink tank) 3 for supplying a liquid such as ink to the liquid discharge unit 2. And a liquid supply communication unit that receives supply of liquid (ink). Note that the ejection port arrays of the liquid ejection unit 2 are arranged along a direction intersecting the head scanning direction.

  As described above, the ink jet recording head 1 is guided by the guide member 5 to land the ejected liquid while moving in parallel (reciprocating) to a recording medium (not shown) such as paper, cloth, resin sheet, and the like. A recorded image or the like is formed. Further, a recording medium such as paper can be conveyed in a direction intersecting the scanning direction of the ink jet recording head 1 while facing a surface where a liquid discharge port (ink discharge port) of the ink jet recording head 1 is opened.

  The first embodiment according to the present invention will be described in more detail.

  FIG. 3 is a vertical cross-sectional view schematically showing an air flow when the ink jet recording head of Embodiment 1 is scanned. FIG. 4 is a longitudinal sectional view showing an example of the shape of the protrusion provided on the ink jet recording head of the first embodiment. FIG. 5 is a longitudinal sectional view showing an example of the shape of the protrusion provided on the ink jet recording head of the first embodiment. FIG. 6 is a longitudinal sectional view showing an example of the shape of the protrusion provided on the ink jet recording head of the first embodiment.

  When the inkjet recording head 1 scans in the Xa direction, which is an example of a scanning direction that is a relative movement direction with respect to the recording medium, an inflow airflow 12 is generated between the inkjet recording head 1 and the recording medium 7 as shown in FIG. . The ink jet recording head 1 of the present embodiment includes a surface (first surface) provided with a liquid ejection unit 2 and facing the recording medium, and a surface opposite to the surface (second surface). A housing having Furthermore, an opening serving as a first opening is provided between the edge of the surface of the housing on which the liquid discharge unit 2 is provided, on the front side in the scanning direction (the end of the first surface), and the liquid discharge unit 2. 11a is provided. The opening 11a allows the atmosphere (inflow airflow 12) flowing in the space between the inkjet recording head 1 and the recording medium 7 to flow along with the scanning of the inkjet recording head 1 in the casing. It is to lead to. Thereby, the amount of the inflow airflow 12 flowing into the space of the aforementioned area from the front of the inkjet recording head 1 in the scanning direction can be effectively reduced.

  The first surface and the second surface need only be disposed on different sides of the inkjet recording head 1 in the scanning direction. The first surface and the second surface are not necessarily limited to the case of facing each other. The positional relationship between the two surfaces is similarly established in the following second and subsequent embodiments.

  The opening 11a in front of the liquid ejection unit 2 in the scanning direction communicates with the outlet-side opening 11b provided on the opposite surface. The outlet-side opening 11 b as the second opening communicates with the opening 11 a on the opposite side of the housing by the airflow discharge channel 11. An airflow discharge passage 11 for reducing the inflow airflow 12 is provided in the casing of the inkjet recording head 1. In addition, a protrusion a21 is provided between the opening 11b on the outlet side of the airflow discharge channel 11 and the edge of the casing on the front side in the scanning direction (the edge of the second surface). The airflow discharge channel 11 discharges a part of the inflow airflow 12 to the side opposite to the recording medium 7 side of the ink jet recording head 1 and reduces the inflow airflow 12 flowing into the space of the liquid ejection unit 2 -recording medium. Yes. Further, the protrusion a21 is located on the Xa direction side (upstream side in the relative movement direction of the airflow, in other words, on the front side in the scanning direction when performing the recording of the ink jet recording head 1 with respect to the outlet position of the airflow discharge passage 12. ).

  During the above-described scanning, air flows along the ink jet recording head 1, but flow separation occurs on the surface of the ink jet recording head 1 on which the protrusions a <b> 21 are provided. It is bent like As a result, the pressure inside the bent flow, that is, the pressure at the outlet of the airflow discharge passage 11 decreases. As a result, a pressure difference is generated between the inlet and the outlet of the airflow discharge channel 11, and a part of the inflow airflow 12 between the ink jet recording head 1 and the recording medium 7 flows into the airflow discharge channel 11. Is discharged to the opposite side of the recording medium 7 side.

  In particular, the air flow discharge channel 11 is installed on the upstream side of the liquid discharge unit 2 with respect to the inflow air flow 12. For this reason, when the ink jet recording head 1 is scanned as described above, the inflow airflow 12 toward the space between the liquid ejection unit 2 and the recording medium 7 can be reduced.

  The shape of the protrusion a21 is a shape in which a triangular prism is laid down in FIG. 1, but the slope of the protrusion a21 shown in the cross-sectional view of FIG. 3 does not have to be a straight line. In order to increase the effect of bending the flow, it may be configured by a curve like a protrusion b21 shown in the cross-sectional view of FIG. Or you may use the prism which a cross section is square shape like the projection part c21 shown in FIG.5 and FIG.6.

  In addition, the dimensions such as the height and width of the protrusion a21, the depth, and the distance to the airflow discharge channel 11 are determined according to the shape of the ink jet recording head 1, the scanning speed thereof, and the like. It is determined by how far the strength of the inflow airflow 12 generated in between is reduced. With such a configuration, the inflow airflow 12 generated between the ink jet recording head 1 and the recording medium 7 is reduced, and the influence on the liquid ejected from the liquid ejecting unit 2 is reduced. It becomes possible to make it small.

  In other words, the phenomenon that the central portion in the scanning width direction of one recording scan becomes dark, which is caused by the deviation of the central portion of the discharge port row toward the inside of the discharge port row, rather than the end portion of the discharge port row, The amount of deflection can be reduced without changing the scanning speed.

  FIG. 7A shows that the central portion in the scanning direction, which is obtained by using the conventional ink jet recording head, is larger in the central portion of the discharge port row than the end portion of the discharge port row, and is deeper toward the inside of the discharge port row. It is the schematic diagram which showed the phenomenon which becomes. The graph of FIG. 7B represents the amount of deviation in the ejection port array direction at the location (B portion) where the central portion of the recording scan obtained at this time is dark. The vertical axis of this graph indicates the amount of deflection in the direction of the discharge port array, and the horizontal axis indicates the number of discharge port lines. The scanning speed of the ink jet recording head is 0.5 m / s, the volume of ejected ink is 1 pl, and the number of ejection ports is 256.

  Here, how to read the graph will be described. The deviation amount “0” in the ejection port array direction indicates that the landing position of the ejection liquid on the recording medium 7 is the same as the design value. Therefore, a positive value from the outermost discharge port at one end of the discharge port array to the 128th discharge port indicates that the landing position is moving from the designed landing position toward the center of the discharge port array. . A negative value indicates that the landing position is moving toward one end of the discharge port array. From the 129th discharge port to the 256th discharge port on the basis of the endmost discharge port at one end of the discharge port array, the positive and negative values are opposite to those of the 128th discharge port. The “movement amount” of this landing position is defined as “the amount of deflection”.

  From the graph of FIG. 7B, it can be seen that the landing position of the discharge liquid has moved greatly toward the vicinity of the center of the discharge port array. Thereby, since the landing dots overlap each other due to the collection of the ejected liquid, the central portion in the width direction of the recording scan becomes dark as shown in FIG. 7A.

  In contrast, FIG. 8A shows a schematic diagram in which recording is performed by the ink jet recording head 1 according to Embodiment 1 of the present invention. FIG. 8B shows a graph representing the amount of deflection in the ejection port array direction at the same position C as in FIG. 7B used as a comparative example at that time. From this graph, it can be seen that the overall amount of deflection is a gentle range width of 20 μm. Therefore, even if recording is performed, the central portion in the width direction of the recording scan does not become dark as shown in FIG. 8A.

(Embodiment 2)
Next, Embodiment 2 as another embodiment according to the present invention will be described. FIG. 9 is a perspective view showing a basic configuration of the inkjet recording head 1 according to the second embodiment. The basic configuration example of the ink jet recording apparatus on which the ink jet recording head 1 of the present embodiment is mounted is the same as the configuration shown in the first embodiment, and is not shown in the drawing, and the description thereof is omitted.

  Hereinafter, a feature point different from the first embodiment will be mainly described in the second embodiment of the present invention. Portions that are not particularly described are the same as those in the first embodiment.

  When the inkjet recording head 1 scans in the Xa direction and the Xb direction, which are examples of the scanning direction that is a relative movement direction with respect to the recording medium 7, an inflow air current is generated between the inkjet recording head 1 and the recording medium 7. In order to reduce the inflow airflow, the airflow discharge channel 11 provided with the projection a21 at the outlet portion is provided so as to sandwich the liquid discharge portion 2 of the inkjet recording head 1 with respect to the scanning direction.

  Further, a protrusion 21a provided at the outlet of the airflow discharge channel 11 in the direction in which the inkjet recording head 1 is scanned comes out of the casing of the inkjet recording head 1 and also in the scanning direction. The protruding portion 21a on the opposite side to is accommodated in the housing. For example, when the inkjet recording head 1 is scanned in the scanning direction Xa shown in FIG. 9, the protruding portion 21 a on the right side of the drawing in FIG. 9 protrudes, and the protruding portion 21 a on the left side of the drawing is accommodated and stored in the inkjet recording head 1. Hidden inside.

  10 and 11 are partial cross-sectional schematic views showing a configuration example for allowing the protrusion 21a to protrude and to be housed.

  When the inkjet recording head 1 is scanned in the Xa direction from the state shown in FIG. 10, the plate A31 is pushed as shown in FIG. 11 by the pressure due to the air resistance during the scanning. As a result, the connecting rod A32, the connecting rod B33, and the connecting rod C34 are moved, and the protrusion 21a housed inside the ink jet recording head 1 is the recording medium (paper) side of the casing of the ink jet recording head 1. It comes out from the opposite side. At this time, the protruding portion 21a is stopped at a fixed protruding length from the opposite surface by the stopper 35 provided on the protruding portion 21a.

  Next, when the pressure on the plate A31 disappears, that is, when the scanning direction of the ink jet recording head 1 is opposite to the Xa direction, the projection A is returned to the original position so that the protrusion 21a is inside the head casing. Will be stored. The protrusion / storage mechanism of this example uses the pressure generated by the movement of the ink jet recording head 1, but it may be an electric type using a diaphragm.

  By installing the inflow air flow exhaust path 11 in this manner, reciprocal scanning recording can be performed using the ink jet recording head 1, so that the image forming time on the recording medium 7 can be shortened.

  The shape of the protrusion at this time may be the same as that of the first embodiment, and is not caught by this embodiment.

  Also in this embodiment, the result of image recording at the time of reciprocating scanning recording is the same as that shown in FIGS. 8A and 8B disclosed in the first embodiment.

(Embodiment 3)
Next, Embodiment 3 as still another embodiment according to the present invention will be described. 12 and 13 are perspective views showing the basic configuration of the ink jet recording head according to the third embodiment. Note that the basic configuration example of the ink jet recording apparatus on which the ink jet recording head of this embodiment is mounted is the same as the apparatus configuration shown in the first embodiment, and is not shown in the drawing, and the description thereof is omitted. The third embodiment shows a head configuration example in the case where the liquid holding unit (ink tank) 3 of the ink jet recording head 1 in the first and second embodiments described above has a large capacity.

  Hereinafter, a feature point different from the first embodiment will be mainly described in the third embodiment of the present invention. Portions that are not particularly described are the same as those in the first embodiment.

  When the inkjet recording head 1 scans in the Xa direction, which is an example of a scanning direction that is a relative movement direction with respect to the recording medium 7, an inflow airflow is generated between the inkjet recording head 1 and the recording medium 7.

  When the capacity of the liquid holding unit 3 is increased and the entire casing of the ink jet recording head 1 is enlarged, the air flow discharge passage 11 provided in the ink jet recording head 1 becomes longer in order to reduce the inflow air flow described above. Therefore, in order to shorten the length of the airflow discharge channel 11, the ink jet recording head 1 is provided with a penetrating portion 24 penetrating in parallel along the scanning direction. And the exit of the airflow discharge flow path 11 was formed in the inner surface of this penetration part 24, and the projection part a21 was provided in the exit part.

  Further, an ink supply path 9 from the liquid holding unit 3 to the liquid ejection unit 2 is installed on the side wall of the through-hole 24 in the recording head 1 (see FIG. 14).

  By arranging the ink supply path 9 in this way, the liquid holding part 3 can be separated from the liquid discharge part 2 and the penetrating part 24 can be arranged close to the liquid discharge part 2. Can be shortened. As a result, it is possible to provide the air flow discharge flow path 11 having a small flow path resistance, so that the inflow air flow generated between the inkjet recording head 1 and the recording medium 7 can be greatly reduced. As a result, the influence of the inflow airflow on the discharge liquid 8 discharged from the liquid discharge unit 2 is reduced, and the amount of deflection can be reduced.

  In addition, as shown in FIG. 13, the air flow discharge channel 11 having the protrusions a <b> 21 provided at the outlet portion is provided so as to sandwich the liquid discharge unit 2 with respect to the scanning direction, and the outlet of each air flow discharge channel 11 is provided. If it is formed on the inner surface of the penetrating portion 24, reciprocal scanning recording becomes possible.

  The shape and dimensions of the penetrating portion 24 described above are the length and shape of the airflow discharge passage 11 and the size and shape of the protrusions 21a, 22b, and 23c installed at the outlet portion of the inflow airflow discharge passage 11. Determined by combination. Further, depending on how much the strength of the inflow airflow generated between the ink jet recording head 1 and the recording medium 7 is reduced depending on the shape of the ink jet recording head 1, the scanning speed to be used, the shape of the housing of the ink jet recording apparatus 4, and the like. Is also determined.

  Also in the present embodiment, the printing results at the time of scanning recording are the same as those shown in FIGS. 8A and 8B disclosed in the first embodiment.

(Embodiment 4)
In the above three embodiments, the ink jet recording head 1 having the liquid ejection part 2 and the liquid holding part 3 is also provided with the air flow discharge channel 11 and the various protrusions 21, 22, and 23. Met.

  In the present embodiment, the airflow discharge path 11 and the various projections 21, 22, and 23 are provided not on the inkjet recording head 1 but on the carriage 6. For example, FIG. 15 is a perspective view of a configuration in which the liquid ejection unit 2 and the liquid holding unit 3 form an ink jet recording head and can be attached to and detached from the carriage 6 provided with the airflow discharge channel 11. . The opening 11a is provided on the surface of the casing of the carriage 6 facing the recording medium, and the opening 11b is provided on the surface of the casing of the carriage 6 opposite to the surface on which the opening 11a is provided.

  FIG. 15 is a diagram in which the configuration corresponding to the first embodiment is replaced with the fourth embodiment, but the configuration corresponding to the second and third embodiments is not particularly shown with reference to the drawings. Configuration can be applied.

  That is, each implementation is also achieved by a configuration obtained by combining the carriage 11 provided with the airflow discharge path 11 and the various protrusions 21, 22, and 23 and the respective characteristic configurations in the above-described embodiments. An effect equivalent to the effect obtained in the form can be obtained.

1 is a perspective view illustrating a configuration of an ink jet recording head that is Embodiment 1 of the present invention. FIG. 1 is a perspective view showing a basic configuration of an ink jet recording apparatus equipped with the ink jet recording head of Embodiment 1. FIG. FIG. 2 is a longitudinal sectional view schematically showing an air flow when the ink jet recording head of Embodiment 1 is scanned. FIG. 3 is a longitudinal sectional view illustrating a shape example of a protrusion provided in the ink jet recording head according to the first embodiment. 3 is a longitudinal sectional view showing an example of the shape of a protrusion provided on the inkjet recording head of Embodiment 1. FIG. 3 is a longitudinal sectional view showing an example of the shape of a protrusion provided on the inkjet recording head of Embodiment 1. FIG. FIG. 10 is a schematic diagram illustrating a phenomenon in which a central portion of a recording scan caused by deviation of ejected ink becomes dark when a conventional inkjet recording head is used. It is the graph showing the amount of deflection | deviation of the discharge port row direction in the B section shown to FIG. 7A using the conventional inkjet recording head. FIG. 3 is a schematic diagram illustrating a phenomenon in which a central portion of a recording scan caused by deviation of ejected ink is dark when the ink jet recording head of Embodiment 1 is used. FIG. 8B is a graph showing the amount of deflection in the discharge port array direction at a C portion shown in FIG. It is a perspective view which shows the basic composition of the inkjet recording head which is Embodiment 2 of this invention. FIG. 10 is a schematic cross-sectional view illustrating a configuration example for realizing the rise and sink of a pair of protrusions provided in the ink jet recording head of Embodiment 2, and is a diagram illustrating a state where the protrusions are sinking. FIG. 10 is a schematic cross-sectional view illustrating a configuration example for realizing the rise and sink of a pair of protrusions provided in the ink jet recording head of Embodiment 2, and is a diagram illustrating a state where the protrusions are raised. It is a perspective view which shows the structure of the inkjet recording head which is Embodiment 3 of this invention. It is a perspective view which shows the modification (configuration example in which reciprocating scanning recording is possible) of FIG. It is the side view which looked at the inkjet recording head shown in FIG. 12 toward the scanning direction, and is a figure which shows the state which is discharging the ink. FIG. 6 is a perspective view of a configuration that is a fourth embodiment of the present invention, in which a liquid discharge unit and a liquid holding unit form an ink jet recording head and can be attached to and detached from a carriage provided with an airflow discharge channel.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inkjet recording head 2 Liquid discharge part 4 Inkjet recording apparatus 7 Droplet receiving member (paper)
11 Inflow airflow discharge passages 11a, 11b Opening 12 Inflow airflow 21 Protrusion a
22 Protrusion b
23 Projection c
Xa, Xb Scan direction

Claims (12)

A liquid discharge recording head having a liquid discharge portion for discharging liquid,
A housing having a first surface provided with the liquid ejection portion, and a second surface disposed on a side surface different from the side surface on which the first surface is disposed;
A first opening provided between the liquid ejection section and the edge of the first surface;
A second opening provided on the second surface and communicating with the first opening;
A liquid discharge recording head comprising: a protrusion provided on the second surface between the end of the second surface corresponding to the end of the first surface and the second opening.   The liquid ejection recording head according to claim 1, wherein the protruding portion is capable of protruding and retractable with respect to the housing.   A penetrating portion that penetrates the housing along the first surface is provided, the second opening is disposed on an inner surface of the penetrating portion, and a liquid is disposed on the liquid discharge portion on the side wall portion of the penetrating portion. The liquid discharge recording head according to claim 1, wherein a liquid supply communication section for supplying the liquid is installed.   The end side of the housing on the front side in the scanning direction when the liquid ejection recording head is mounted on the liquid ejection recording apparatus and scanned to execute recording with respect to the liquid ejection unit. The liquid discharge recording head according to claim 1, wherein the liquid discharge recording head is an end side.   Inflow generated in an area between the liquid discharge recording head and the recording medium when the liquid discharge recording head is mounted on the liquid discharge recording apparatus and scanned with respect to the recording medium in order to execute recording 5. The liquid discharge recording head according to claim 1, further comprising an air flow discharge channel that communicates the first opening and the second opening for discharging an air flow from the region. 6. A liquid discharge recording apparatus that mounts a liquid discharge recording head having a liquid discharge portion that discharges liquid onto a recording medium and performs discharge recording while scanning the liquid discharge recording head.
The liquid ejection comprising: a first surface provided with the liquid ejection section; and a second surface disposed on a side different from the side in the scanning direction of the liquid ejection recording head on which the first surface is disposed. A recording head housing,
A first opening provided in the housing between the liquid ejection unit and the edge of the first surface;
A second opening provided on the second surface of the housing and in communication with the first opening;
A protrusion provided on the second surface between the end of the second surface corresponding to the end of the first surface and the second opening;
A scanning guide for scanning the recording medium with the liquid ejection recording head,
The liquid ejection recording apparatus, wherein the first opening is disposed in front of the liquid ejection unit in the scanning direction when recording is performed, and the protrusion is disposed in front of the second opening in the scanning direction.   The liquid ejection recording apparatus according to claim 6, wherein the protrusion is protrudeable and retractable with respect to the housing.   A penetrating portion that penetrates the housing along the first surface is provided, the second opening is disposed on an inner surface of the penetrating portion, and a liquid is disposed on the liquid discharge portion on the side wall portion of the penetrating portion. The liquid discharge recording apparatus according to claim 6, wherein a liquid supply communication unit for supplying the liquid is installed.   When the liquid ejection recording head is scanned with respect to the recording medium to perform recording, the inflow airflow generated in the area between the liquid ejection recording head and the recording medium is discharged from the area. The liquid discharge recording according to any one of claims 6 to 8, wherein an air flow discharge channel that communicates the first opening and the second opening is provided in the liquid discharge recording head. apparatus. A liquid discharge unit having a carriage on which a liquid discharge recording head having a liquid discharge unit for discharging liquid onto a recording medium is mounted, and performing discharge recording while scanning the carriage on which the liquid discharge recording head is mounted A recording device,
A first surface facing the recording medium together with the liquid ejecting portion; and a second surface disposed on a side different from the side in the scanning direction of the liquid ejection recording head on which the first surface is disposed. A housing of the carriage;
A first opening provided in the housing between a portion where the liquid ejection unit is disposed and an edge of the first surface;
A second opening provided on the second surface of the housing and in communication with the first opening;
A protrusion provided on the second surface between the end of the second surface corresponding to the end of the first surface and the second opening;
A scanning guide for scanning the carriage with respect to the recording medium,
The liquid discharge recording apparatus, wherein the first opening is disposed in front of a scanning direction of the portion where the liquid discharge unit is disposed, and the projection is disposed in front of the second opening in the scanning direction. .   The liquid ejection recording apparatus according to claim 10, wherein the protrusion is protrudeable and retractable with respect to the housing.   When the liquid discharge recording head mounted on the carriage is scanned with respect to the recording medium to perform recording, an inflow airflow generated in a region between the liquid discharge recording head and the recording medium is 12. The liquid discharge recording apparatus according to claim 10, wherein an airflow discharge channel that communicates the first opening and the second opening for discharging from an area is provided in the carriage.

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