JP2004209747A - Inkjet head, method of manufacturing the same, and printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet head capable of preventing a malfunction due to a heat from occurring by adequately radiating the heat. <P>SOLUTION: In a line head 35, ink is supplied to an ink channel 331 from an ink tank section 32 through an ink supply pipe 336 and a driving current is applied to a heating element 321 from a circuit on a printed board 360 through a terminal plate B 341 and a golden wire 342. In a nozzle applied with the current, a heating element 321 heats, a bubble is created on the surface of the heating element 321, and then ink having a volume roughly equal to that of the bubble is ejected from an ink ejection hole 311. While the heat by a heater chip 322 is accumulated a good deal by successive printing, as a fluid passage plate 330 made of an aluminum alloy is bonded to the heater chip 322, the heat generated on the heater chip 322 is efficiently radiated by the channel plate 330 so that it is possible to prevent a malfunction due to abnormal rising of the temperature from occurring. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an inkjet head suitable for application to an inkjet printer or the like that prints an image by ejecting ink from ink ejection holes (ink ejection nozzles), a method of manufacturing the same, and a printer using the inkjet head. .
[0002]
[Prior art]
An ink jet printer that prints and records characters, figures, images, and the like (hereinafter collectively simply referred to as images) on a recording medium such as printing paper (hereinafter simply referred to as printing paper) by discharging ink from the discharge holes. Are widely used because of their advantages such as low running cost, downsizing of the apparatus, and easy color printing.
2. Description of the Related Art A recording head of an ink jet recording apparatus, that is, an ink jet head discharges ink from a discharge hole by applying some pressure to a liquid chamber containing ink. Various means have been proposed for applying pressure to the liquid chamber. A piezo method using a piezo element as a piezoelectric element and a bubble method using a heating element are widely known. In the bubble method, a heating element is provided corresponding to an ink ejection hole, the ink is boiled by the heat generated by the heating element, and the ink is ejected from the ejection hole by the pressure of bubbles generated at this time.
[0003]
As the structure of the ink jet head, a fine groove is formed in a plate member such as a metal plate or a glass plate by cutting or etching and the like, and the plate member is joined to another plate member serving as a lid of the flow path, and the ink flow path is formed. which was formed is widely known. A groove is formed by forming a groove wall made of a photosensitive resin on a substrate on which a discharge energy generating element such as a heating element is disposed, and a plate member is joined to another plate member serving as a lid of a flow path. A method for forming an ink flow path is also known (for example, see Patent Document 1).
In addition, the plate member having the groove and the plate member serving as the lid are generally joined by an epoxy resin-based adhesive when the member serving as the lid is made of glass, ceramic, metal, plastic, or the like. When the member serving as the lid is made of a thermoplastic resin such as an acrylic resin, an ABS resin, or a polyethylene resin, the lid may be heat-sealed without using an adhesive.
[0004]
[Patent Document 1]
JP-A-57-43876 JP
[0005]
[Problems to be solved by the invention]
By the way, as a printing method in a printer device, there is a method in which a head is reciprocated in a direction perpendicular to a recording paper conveyance direction (a width direction of the recording paper) to perform printing on the entire surface of the paper, There is a method of performing printing by feeding a recording sheet under a fixed head to cover. The head used in the former method is a serial head, and the head used in the latter method is a line head. Comparing the two, the line head method has the advantage that it does not need to move the head, so that a drive mechanism is unnecessary and high-speed printing is possible, and it is often used more favorably than the serial head.
[0006]
However, if an attempt is made to form a line head by the ink jet method, it is necessary to arrange the ink discharge nozzles at a close pitch over a length corresponding to the print width, and the structure becomes complicated and manufacturing is difficult.
In particular, in the bubble method, the length of the head is long, so that heat generated from the heating element is not sufficiently dissipated, so that a portion of the elongated line head may have a high or low temperature, or the head may be heated to a high temperature. May be. Therefore, in the line head in which the lid member is bonded to the grooved plate, the plate serving as the lid of the grooved plate may thermally expand, causing a problem such as separation of the bonding surface and leakage of ink. . In addition, thermal expansion may cause distortion or non-uniform stress in a specific portion of the line head, peeling off the adhesive, and possibly causing ink leakage or the like.
[0007]
The present invention has been made in view of such a problem, and an object of the present invention is to provide an ink jet head that can be used as a line head, and particularly to appropriately dissipate heat and prevent the occurrence of a defect caused by heat. It is to provide an ink jet head and a manufacturing method thereof that.
Another object of the present invention is to provide a printer capable of performing high-quality printing at high speed by providing an ink-jet head type line head that appropriately dissipates heat and prevents occurrence of a defect caused by heat. It is to provide a device.
[0008]
[Means for Solving the Problems]
In order to solve the above problem, an inkjet head according to the present invention includes a plurality of ink ejection nozzles, a heating member provided corresponding to the ink ejection nozzle, and ejecting ink from the ink ejection nozzle, and a heating member. A member formed of aluminum or an aluminum alloy that directly or indirectly contacts the ink discharge nozzle, and a flow path forming member that forms an ink flow path that supplies ink to each of the ink discharge nozzles.
Preferably, the ink-jet head according to the present invention, the plurality of ink discharge nozzles are line heads arranged in a straight line.
[0009]
In an ink jet head having such a configuration, ink is supplied to each ink ejection nozzle via an ink flow path. In each ink discharge nozzle, pressure is applied to the ink stored in the vicinity of the ink discharge nozzle by the heat generated by the corresponding heating member, and the ink is discharged from the ink discharge nozzle. The heat generated at the time of ink ejection is quickly dissipated via a flow path forming member that forms an ink flow path with which each heat generating member is in direct or indirect contact. Therefore, heat does not partially accumulate and the temperature does not become abnormally high, and the joined members do not peel off and the members do not deform. In addition, the function it is possible to prevent the occurrence of a situation that to stop. Thus, the inkjet head can be configured to be long enough to be used as a line head.
Further, the flow path forming member is formed of aluminum or an aluminum alloy. Aluminum is a material having high heat conductivity among metal materials and thus has good heat dissipation, so that even in a long head, heat distribution can be made uniform and heat dissipation can be appropriately performed.
[0010]
Also preferably, the contact surface with the ink of the flow path forming member, for example, a resin film of polyimide deposited film or the like is formed.
Metals such as aluminum or an aluminum alloy to form a flow path forming member, there is a property of easily being corroded by the aqueous ink. Therefore, by covering the surface where the flow path forming member and the ink come into contact with each other with a resin film, it is possible to prevent the ink from coming into contact with the flow path forming member and to prevent corrosion. The polyimide vapor-deposited film has no pinholes because it is a precision coating film, and the film thickness can be controlled. Moreover, because of the high less electrical insulation impurities, it is also possible to suppress the occurrence of corrosion current due to the difference in ionization tendency between different metals. Therefore, it is preferable to protect the flow path forming member from the ink.
[0011]
Further, in the method for manufacturing an ink jet head according to the present invention, a plurality of ink discharge nozzles are arranged at a predetermined pitch, and a heat generating member for discharging ink from the ink discharge nozzles in correspondence with the ink discharge nozzles is provided. A flow path forming member formed of an aluminum alloy and forming an ink flow path for supplying ink to each of the ink discharge nozzles is disposed so as to be in direct or indirect contact with the heat generating member.
Preferably, a resin film is formed on a contact surface of the flow path forming member with the ink, and the flow path forming member on which the resin film is formed, the surface on which the resin film is formed forms an ink flow path surface. Arrange as configured.
[0012]
Further, the printer device according to the present invention is provided with a plurality of ink ejection nozzles, a heating member provided corresponding to the ink ejection nozzles, for directly or indirectly contacting the heating member for ejecting ink from the ink ejection nozzles. And a flow path forming member that forms an ink flow path that supplies ink to each of the ink discharge nozzles.
Preferably, the ink jet head, the plurality of ink discharge nozzles is a line head which is disposed on the printed entire width linearly.
[0013]
In the printer apparatus having such a configuration, in the ink jet head, each heat generating member is in direct or indirect contact with a flow path forming member that forms an ink flow path. The flow path forming member is formed of aluminum or an aluminum alloy. Therefore, heat generated from the heat generating member during ink ejection is radiated rapidly through the flow path forming member, heat to the ink jet head is never part is partially accumulated becomes abnormally high temperature. Therefore, it is possible to prevent the joined members from being separated or the members from being deformed, and to prevent the function from stopping. As a result, appropriate printing is performed by the inkjet line head, high-speed to the appropriate printing capable printer apparatus is provided.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention with reference to FIGS. 1 to 10 will be described.
In the present embodiment, the present invention will be described by exemplifying a printer apparatus having an inkjet line head and performing full color printing, that is, a color inkjet printer.
[0015]
First, the overall configuration of the inkjet printer according to the present embodiment will be described with reference to FIGS.
FIG. 1 is a perspective view showing the appearance of the main body of the ink jet printer 1, and FIG. 2 is an exploded perspective view showing a schematic structure of the ink jet printer 1.
As shown in FIG. 1, the inkjet printer 1 includes a main body 40, a lid 41, a paper feed cassette 42, a paper discharge tray 43, and an operation panel 44. Further, as shown in FIG. 2, the ink jet printer 1 has a print head cartridge 30 in a main body 40.
[0016]
The main body 40 accommodates a print paper transport mechanism, an overall control unit, and the like. The print head cartridge 30 and the paper feed cassette 42 are detachably mounted on the main body 40. This is the main body of the printer that performs the processing.
[0017]
The print head cartridge 30 is a print head unit that performs full-color printing of a desired image on printing paper.
Printhead cartridge 30, as shown in FIG. 2, has a head portion 31, the ink tank unit 32, the cartridge case 33 and the cap 34.
Head portion 31 includes magenta, yellow, four line heads corresponding to four colors of cyan and black. The ink tank unit 32 has four ink tanks corresponding to each color of the head unit 31. These four line heads and four ink tanks are housed in the cartridge case 33. Further, a cap 34 for protecting the nozzle portion of the inkjet head is mounted on the printing surface (ink ejection surface).
[0018]
Each line head of the head unit 31, across the printing width of the ink jet printer 1 configured ink discharge nozzles are arranged linearly at a predetermined pitch. Note that the printing width of the inkjet printer 1 is a length in a direction perpendicular to the paper transport direction of the maximum size printing paper that can be printed by the inkjet printer 1, and is usually a length in a short side direction of the printing paper. is there. Each line head, the supplied from the corresponding ink tank ink, by selectively ejected from a plurality of ink ejection nozzles arranged in a straight line, a desired image on a print sheet conveyed under the line head Print.
The structure of the line head according to the present invention will be described later in detail.
[0019]
The print head cartridge 30 is a detachable module with respect to the main body 40. As shown in FIG. 2, the print head cartridge 30 is attached to the main body 40 by being inserted in the direction a with the lid 41 of the ink jet printer 1 opened. Is done. In addition, it is detached from the main body 40 by being pulled out in the opposite direction.
Further, the four ink tanks of the ink tank section 32 are configured to be more detachable than the print head cartridge 30. Therefore, replenishment of ink can be easily performed only by replacing the ink tank.
[0020]
The cover 41 is a cover of the main body 40 and is opened and closed when the print head cartridge 30 is replaced.
Paper feed cassette 42 is a case for accommodating the printing paper. Print sheets contained in the sheet cassette 42 is sequentially taken out by the main body 40 inside the paper transport mechanism is subjected to printing.
Discharge tray 43 is provided above the paper feed cassette 42, a means for retaining the discharged print paper.
The paper feed cassette 42 and the paper discharge tray 43 are integrally formed by mounting the paper discharge tray 43 as a lid of the paper feed cassette 42, and this is inserted in the direction of FIG. , Attached to the main body 40.
Operation panel 44, operation buttons or the like print start switch, an operation-status display means for the display means is arranged such status display window.
[0021]
Next, the transport mechanism of the printing paper inside the main body 40 will be described with reference to FIG.
FIG. 3 is a cross-sectional view illustrating a configuration of the paper transport mechanism 10 inside the main body 40 of the inkjet printer 1. FIG. 3A illustrates a print standby state in which the cap 34 of the print head cartridge 30 is mounted on the print head cartridge 30. FIG. 3B is a diagram illustrating a state of the sheet transport mechanism 10 when the cap 34 is retracted to the retreat location 25 when printing is possible.
As shown in FIG. 3, the paper transport mechanism 10 includes a pickup roller 11, a separation roller 12, a guide member 13, a reversing roller 14, an auxiliary roller 15, a first guide plate 16, a transport belt 17, drive rollers 18, 19, having a pinch roller 20, the second guide plate 21, the tension control roller 22, reversing guide plates 23 and reversing conveyance roller 24.
[0022]
The pickup roller 11 rotates from the paper feed cassette 42 by rotating the pickup roller 11 so as to send out the print paper toward the reversing roller 14 while abutting the print paper stored in the uppermost part of the paper feed cassette 42 at a predetermined pressure. Remove the paper.
The separation roller 12 separates the printing paper taken out by the pickup roller 11 one by one. As illustrated, the separation roller 12 includes a pair of rollers 12a and 12b arranged so as to sandwich the printing paper taken out by the pickup roller 11 from the front and back (up and down). The front (upper) roller 12a rotates in a direction to feed the printing paper toward the reversing roller 14, and the back (lower) roller 12b rotates in a direction to return the printing paper to the paper feed cassette 42. Thus, when a plurality of printing papers are taken out by the pickup roller 11, only the uppermost printing paper is sent toward the reversing roller 14. Further, when a torque in the opposite direction to the rotation is applied from the outside, the rear roller 12b loses the torque and rotates in the same direction as the front (upper) roller 12a. As a result, even when there is only one print sheet between the front roller 12a and the back roller 12b, the sheet is appropriately fed in the direction of the reversing roller 14.
[0023]
The guide member 13 guides the printing paper sent from the separation roller 12 to the reversing roller 14.
The reversing roller 14 rotates in the direction indicated by c in FIG. 3, and prints the printing paper taken out of the paper feed cassette 42 or the printing paper that has already been printed on one side for double-sided printing described later. It winds in under the reversing roller 14. By further rotating, the printing paper is rotated about half a turn to reverse the front and back, and is sent out to the first guide plate 16 above the reversing roller 14.
The auxiliary rollers 15a to 15c guide the holding and conveyance of the printing paper so that the printing paper is appropriately wound around the reversing roller 14 and appropriately inverted.
[0024]
The first guide plate 16 receives the printing paper by reverse roller 14 in the reverse roller 14 top, guides it to the conveyor belt 17 direction. Then, the printing paper comes into contact with the conveyance belt 17 at a gentle angle, is sequentially drawn in, and is sent out to the conveyance belt 17 so that the printing paper is finally placed on the conveyance belt 17.
The transport belt 17 is driven to rotate by two drive rollers 18 and 19 and transports the printing paper guided and placed by the first guide plate 16 to a print area below the head unit 31 of the print head cartridge 30. And print it. The distance between the ink discharge surface of the print paper and the head portion 31 of the conveyor belt 17 during printing operation is about 2 mm.
[0025]
Driving rollers 18 and 19 is a roller which drives the conveyor belt 17. The driving furnaces 18 and 19 rotate so that the transport belt 17 sends out the printing paper toward the paper discharge tray 43 at the time of printing and when the printed paper is discharged to the paper discharge tray 43. When reversing the printing paper to perform double-sided printing, the transport belt 17 rotates so as to send the printing paper toward the reversing roller 14.
Further, when the cap 34 of the print head cartridge 30 is retracted or mounted, the drive roller 19 moves downward from the position during normal printing operation, that is, moves away from the print head cartridge 30. When the drive roller 19 moves downward, the transport belt 17 itself also moves downward with the other drive roller 18 as a fulcrum, and the transport belt 17 moves between the transport belt 17 and the lowermost surface (print surface) of the print head cartridge 30. Space is secured. After passing through this space, the retraction and mounting of the cap 34 are performed. The retracted cap 34 is disposed at the retracted place 25 in the main body 10.
[0026]
The pinch roller 20 presses the printing paper placed on the conveyance belt 17 before reaching the printing area, and makes the printing paper adhere to the conveyance belt 17.
The second guide plate 21 guides the printing paper guided by the first guide plate 16 and sent out in the vicinity of the transport belt 17 so as to reliably hit the transport belt 17 at a predetermined position.
The tension control roller 22 presses the transport belt 17 to apply a predetermined tension to the transport belt 17.
[0027]
The reversing guide plate 23 receives the printing paper returned by the transport belt 17 for performing double-sided printing at the end of the transport belt 17 on the reversing roller 14 side, and guides this to the lower side of the reversing roller 14. .
The reversing transport roller 24 is a roller that feeds the printing paper returned by the transport belt 17 in the direction of the reversing roller 14 for performing double-sided printing. Reversing conveyance rollers 24, the tip portions of the rollers are arranged so as to protrude into the conveying path formed by inverting the guide plate 23, the printing paper that has been returned for performing duplex printing, the reverse roller 14 direction send to.
[0028]
The paper conveyance mechanism 10 having such a structure, the printing paper housed in the paper feed cassette 42 is taken out by the pickup roller 11, the separation roller 12 are separated one by one and sent to the reversing roller 14. The printing paper sent to the reversing roller 14 is turned over by the reversing roller 14, and is placed on the transport belt 17 via the first guide plate 16 and the second guide plate 21.
Printing paper placed on the conveyor belt 17 is in close contact by being pressed to the conveying belt 17 by the pinch roller 20, is guided to the recording area below the head portion 31 of the printhead cartridge 30. Then, a desired image is printed by the head unit 31. When performing printing on only one side, the printing paper is discharged from the discharge tray 43 as it is.
[0029]
When performing duplex printing, when finished printing on the one surface, the drive rollers 18 and 19 are reversely rotated, the moving direction of the conveyor belt 17 is reversed, the printing paper printed on the surface is performed reversing roller 14 is conveyed backward in direction. The printing paper conveyed in the reverse direction is guided to the lower portion of the reversing roller 14 via the reversing guide plate 23, and is wound around the reversing roller 14 again. Printing paper caught in reversing roller 14 is placed on the conveyor belt 17 through the first guide plate 16 again, in close contact with the conveyance belt 17 by the pinch roller 20, the head portion 31 of the printhead cartridge 30 It is guided to the recording area of the bottom. Then, a desired image is printed on the back surface by the head unit 31. The printing paper on which the front and back printing has been performed is discharged to the discharge tray 43.
[0030]
Next, the configuration of the print head cartridge 30 of the inkjet printer 1 according to the present invention will be described in detail with reference to FIGS.
FIG. 4 is a cross-sectional view of the print head cartridge 30 in a direction (paper transport direction) perpendicular to the direction in which the line head extends (line head direction). Note that FIG. 4 particularly shows a portion where an ink supply pipe 336 for supplying ink from the ink tank portion 32 to the head portion 31 is provided for ease of description.
As described above, the print head cartridge 30 includes the head unit 31, the ink tank unit 32, the cartridge case 33, and the cap.
[0031]
The head unit 31 includes four line heads 35 corresponding to four colors of yellow (Y), magenta (M), cyan (C), and black (K). _-Y , 35 _-M , 35 _-C And 35 _-K Having. The four line heads, the print head cartridge 30 when it is attached to the body 40 of the inkjet printer 1, so as to face the printing surface to the plane direction of the printing paper conveyed, it is placed in the cartridge case 33. Further, these four line heads are arranged in parallel and installed in the cartridge case 33.
Since all four line heads have the same configuration, hereinafter, when describing the contents common to each line head, they will be simply referred to as the line head 35.
[0032]
The ink tank unit 32, four line heads 35 _-Y , 35 _-M , 35 _-C And 35 _-K Having four ink tanks corresponding to. Ink is supplied from each ink tank to an ink flow path 331 of each line head 35 via an ink supply pipe 336. The ink supply pipes 336 are arranged at several places in the longitudinal direction of each line head 35.
The cartridge case 33 is a case which integrally accommodates the head portion 31 and the ink tank unit 32, not shown, having a grip portion or the like at the time guide and removable for attachment to the main body 40.
The cap 34 is a cover that hermetically protects the ink ejection surface of the head unit 31 and prevents the ink from drying when printing is not performed. When printing is performed, the cap 34 is retracted to the predetermined evacuation location 25 of the main body 40 of the inkjet printer 1 as described above with reference to FIG.
[0033]
Hereinafter, the configuration of the line head 35 will be described in more detail.
5 and 6, the line head 35 shown in FIG. 4 _-Y , 35 _-M , 35 _-C And 35 _-K FIG. 4 is an enlarged sectional view of one of the line heads. FIG. 5 is a cross-sectional view of the line head 35 where the ink supply pipe is not provided. FIG. 6 is a cross-sectional view of the line head 35 where the ink supply pipe 336 is provided, similarly to FIG. It is sectional drawing.
FIG. 7 is an exploded reference drawing of main components of the head unit 31 for easy understanding. FIGS. 8 to 10 show the nozzle sheet 310 and the heater chip, which are the main components. FIG. 3 is a diagram for describing a configuration or arrangement of a dummy chip 322, a dummy chip 323, and a flow path plate 330.
[0034]
As shown in FIGS. 5 and 6, a nozzle sheet 310 is disposed on the ink ejection surface 301 of the head unit 31. The nozzle sheet 310, the opening 312 for performing wiring to the ink discharge hole 311 and the heater chip 322 for ejecting ink are formed. As shown in FIG. 7, the nozzle sheet 310 is formed as one sheet that covers the entire bottom surface of the print head cartridge having four line heads.
[0035]
The ink ejection holes (ink ejection nozzles) 311 shown in FIGS. 5 and 6 are formed substantially linearly at a predetermined pitch over the entire printing width of the line head. More strictly, as shown in FIG. 8, the ink ejection holes 311 are located at positions slightly displaced in a direction perpendicular to the line head direction (positions along two straight lines indicated by broken lines in FIG. 8). , Are formed alternately for each predetermined section. Arrangement of the ink discharge holes 311 are those involved in the construction of the heater chip 322, the reason will be described later.
The opening 312 shown in FIGS. 5 and 6 is an opening for wiring to the heating element 321 of the heater chip 322 and for sealing the wiring 342 provided. As shown in FIG. 8, the openings 312 correspond to a series of ink ejection holes 311 alternately arranged in two rows for each predetermined section, and one continuous outside of the series of ink ejection holes 311 is provided. It is provided as an opening.
[0036]
As shown in FIGS. 5 and 6, on the nozzle sheet 310, a heater chip 322 in which a heating element 321 is embedded and a dummy chip 323 are arranged.
Heater chips 322 is a rod-like member heating element 321 is embedded for ejecting ink from the ink discharge hole 311. A single heater chip 322, dozens or so of the heating element 321 is buried at a predetermined pitch. The number of the heating elements 321 is equal to the number of a series of ink ejection holes 311 alternately arranged for each predetermined section illustrated with reference to FIG. 8, and the pitch is equal to the pitch of the series of ink ejection holes 311. .
[0037]
As shown in FIG. 9, such heater chips 322 are alternately arranged at positions slightly shifted corresponding to the above-described ink ejection holes 311 so that they are substantially continuously arranged in the line head direction. Is done. By arranging the heater chips 322 in this manner, the respective heating elements 321 of the heater chips 322 are arranged near and corresponding to the respective ink ejection holes 311 of the nozzle sheet 310 shown in FIG. Accordingly, the heat generated at the heating elements 321, ink is discharged from the ink discharge hole 311.
Note that heat generated by the heating element 321 embedded in the heater chip 322 is transmitted to a channel plate 330 described later via the heater chip 322.
[0038]
Here, the reason why the ink ejection holes 311 and the heater chips 322 are alternately arranged at positions slightly shifted in the direction perpendicular to the line head direction as shown in FIGS. 8 and 9 will be described.
In order to form a line head with a bubble type ink jet head, the heating elements 321 need to be closely arranged at a very narrow predetermined pitch over the entire printing width in the line head direction. However, it is difficult in manufacturing to form a long heater chip 322 corresponding to the printing width. Therefore, by arranging a plurality of heater chips 322, preferably arranged a heating element 321 to print the entire width. However, since the pitch of the heating elements 321 is very narrow, there is a portion 325 at the end of each heater chip 322 where the heating elements 321 can not be formed in a range longer than the pitch due to the structure.
[0039]
Therefore, as shown in FIG. 9, the heater chips 322 arranged adjacent to each other are slightly shifted in a direction perpendicular to the line head direction, and the heater chips 322 are arranged so that the ends 325 overlap in the line head direction. As a result, the heating element 321 embedded in the heater chip 322 adjacent are arranged substantially continuously in the line head direction.
In the present embodiment, as shown in FIG. 9, the heater chips 322 are alternately arranged on both sides of the lower layer portion 324 of the ink flow path 331 formed in the line head direction. Thus, the heater chip 322, together with the dummy chip 324 to be described later, forms part of the side surface of the lower portion 324 of the ink flow path 331.
Further, since it is necessary to displace the heater chips 322 in this way, the ink ejection holes 311 are also slightly shifted in the paper transport direction corresponding to the heater chips 322 as described above with reference to FIG. Are arranged alternately.
[0040]
The dummy chip 323 is a rod-shaped member having substantially the same cross-sectional shape as the heater chip 322 and connecting the heater chips 322. As shown in FIG. 9, the dummy chips 323 are arranged on the nozzle sheet 310 so as to fill the space between the heater chips 322 of each row of the two rows of heater chips 322 alternately arranged for each predetermined section. . Thus dummy chip 323, together with the heater chip 322, to form a side surface of the lower portion 324 of the ink flow path 331.
The nozzle sheet 310, the heater chip 322, and the dummy chip 323 are joined by an adhesive.
[0041]
As shown in FIGS. 5 and 6, on the heater chip 322 and the dummy chips 323, the channel plate 330 is disposed.
The flow path plate (flow path forming member) 330 is a member that forms an upper layer portion of the ink flow path 331 that supplies ink to each ink ejection hole 311 and that radiates heat transmitted from the heater chip 322. .
As shown in FIG. 10, the flow path plate 330 is a rod-shaped member having a print width, that is, a length substantially equal to the length of the line head. A groove 337 to be an upper layer is formed. The flow path plate 330 is disposed on the heater chip 322 and the dummy chip 323 such that the groove 337 covers the upper part of the lower layer portion 324 of the ink flow path 331 as shown in FIGS. As a result, an ink flow path 331 as one space is formed by the lower layer portion 324 having the heater chip 322 and the dummy chip 323 as side surfaces and the groove 337 of the flow path plate 330.
[0042]
As shown in FIGS. 6 and 10, through holes 335 are formed at predetermined positions in the flow path plate 330 so as to pass through the bottom surface of the groove 337 and the back surface of the flow path plate 330. The ink supply pipe 336 connected to the ink tank of the ink tank unit 32 is connected to the through hole 335. Ink is supplied from the ink tank to the ink flow path 331 through the ink supply pipe 336 and the through hole 335.
In the present embodiment, the channel plate 330 is formed by processing an aluminum alloy by die-cast casting. Further, the surface in contact with the ink flow path plate 330, polyimide deposited film is formed to prevent corrosion by water-based inks. Since the flow path plate 330 is bonded to the heater chip 322 and the dummy chip 323 with an adhesive, a polyimide vapor-deposited film is not formed on the bonding portion. At the time of film formation, a masking process is performed on the joint surface between the heater chip 322 and the dummy chip 323 to deposit a polyimide film, so that a polyimide vapor-deposited film is not formed at the joint.
[0043]
Also, the portion disposed on the heater chip 322 of the channel plate 330, as shown in FIG. 10, the cutout portion 338 is formed. That is, as is clear from further reference to FIGS. 5 and 6, the wall thickness of the side wall of the groove 337 on which the heater chip 322 is disposed is formed smaller than the wall thickness of the side on which the dummy chip 323 is disposed. Is done. Thereby, as shown in FIGS. 5 and 6, a gap 334 for disposing the B terminal plate 341 is formed between the flow path plate 330 on which the heater chip 322 is disposed and the head frame 350 described later. Is done.
[0044]
B terminal plate 341 is a terminal board for applying a current to each heating element 321 embedded in the heater chip 322.
As shown in FIG. 7, B terminal plate 341 is configured to correspond to the heater chips 322. A plurality of terminals are provided on one B terminal plate 341 so that current can be independently applied to the heating elements 321 embedded in one heater chip 322. The B terminal plate 341 is inserted into a gap 334 between the flow path plate 330 and the head frame 350 adjacent to each heater chip 322 as shown in FIGS.
[0045]
The tip of the B terminal plate 341 attached to the gap 334 is configured to reach the vicinity of the above-described opening 312 provided in the nozzle sheet 310. In the space formed by the opening 312, each terminal of the B terminal plate 341 and each heating element 321 of the heater chip 322 are connected by a gold wire 342. Opening 312 which allow for B terminal plate 341 and the heater chip 322 connection is made by the gold wire 342 is sealed by the resin 343.
The other end of the B terminal plate 341 is fixed and supported on a printed circuit board 360 described later. The connector pins 344 of the terminals is connected to a circuit of the printed circuit board 360. As a result, the current for each heating element 321 output from the circuit formed on the printed board 360, that is, for each nozzle 311 is applied to the heating element 321 via the B terminal plate 341 and the gold wire 342.
[0046]
As shown in FIGS. 5 and 6, the line head 35 having such a configuration is disposed so as to be surrounded by a head frame 350 as a reinforcing material. A printed circuit board 360 on which a circuit for driving each nozzle is formed is disposed on the ink tank section 32 side.
As shown in FIG. 7, the head frame 350 has one opening 351 in which each line head is disposed, and is a single member configured to extend over the entire head unit 31. Thus, the four line heads are integrally held as the head unit 31.
The printed circuit board 360 is formed by a circuit that controls each line head of the head unit 31 based on a control signal from a higher-level control device (not shown), that is, a circuit that controls each heating element 321 that ejects ink from each nozzle. Substrate.
The printed circuit board 360 is bonded to the head frame 350 with an adhesive.
[0047]
Above respective components as described can be secured by adhesive, four line heads 35 _-Y , 35 _-M , 35 _-C And 35 _-K , And a head unit 31 having them.
[0048]
Next, the operation of the print head cartridge 30 having such a configuration will be described.
The inks of the respective colors are supplied from the respective ink tanks of cyan (C), magenta (M), yellow (Y), and black (K) of the ink tank section 32 via the ink supply pipe 336 to the ink flow paths 331 of the respective line heads 35. Supplied to The ink supplied to the ink flow path 331 is supplied to all the ink ejection holes 311 of each line head.
On the other hand, based on the control signal input from the control unit of the inkjet printer 1, in the circuit of the printed circuit board 360, the line heads 35 of the head portion 31 _-Y , 35 _-M , 35 _-C And 35 _-K A control current for driving each of the nozzles is generated. Generated control current is applied to the heating element 321 through the B terminal plate 341 and the gold wire 342.
In each nozzle a current is applied, the heating elements 321 generate heat, thereby a bubble is generated from the surface layer of the heating element 321. As a result, the ink near the ink ejection hole 311 in the lower layer portion 324 of the ink flow path 331 is pressed, and the ink is ejected from the ink ejection hole 311.
[0049]
When the application of the current to the heating element 321 ends, the heating of the heating element 321 also ends, the heating element 321 is substantially cooled, and the bubbles disappear.
Such processing is sequentially performed in synchronization with the conveyance of the printing paper, and a desired image is printed on the printing paper by selectively discharging ink for each line of the printing paper. Further, by continuing such printing, the heat generation from the heater chip 322 becomes considerable. However, since the flow path plate 330 made of an aluminum alloy is joined to the heater chip 322, the heat generated in the heater chip 322 is transmitted to the flow path plate 330, and is efficiently radiated. As a result, the line head 35 is rapidly cooled.
[0050]
As described above, in the ink jet printer 1 of the present embodiment, the channel plate 330 of the head unit 31 uses an aluminum alloy having a high thermal conductivity among resins and metals. Therefore, it is possible to reduce the temperature difference due to the location of one line head, uniform heat can be achieved. As a result, local thermal expansion can be suppressed, and the stress applied to the member can be reduced.
Also, aluminum is for general resin than linear expansion coefficient is small, a small elongation of the material from the resin by heat. Therefore, when the material thermally expands, the stress exerted on the adhesive and other components can be reduced, and in particular, the peeling of the adhesive can be prevented.
[0051]
Further, since a good heat dissipation is lowered quickly heat the heater chip 322, it can be discharged appropriately ink stably.
Also, aluminum has specific gravity smaller among metals, thereby the weight of the member.
Further, the flow path plate, since manufactured by die-cast casting, low manufacturing costs, is also suitable for mass production.
Further, the aluminum surface may adhesiveness, can secure reliability during assembly production.
[0052]
In the present embodiment, the contact surface of the flow path plate 330 with the ink is subjected to polyimide vapor deposition. As a result, it is possible to an aluminum alloy and protected from the ink, to prevent corrosion due to for example, aqueous ink or the like. In particular, since the polyimide deposited film precision coating, pinholes are not effective.
In addition, since polyimide deposition has high electrical insulation, current can flow due to a difference in ionization tendency between the nozzle sheet and the aluminum alloy flow path plate 330, and corrosion can be prevented from occurring.
Further, since the polyimide deposition is a means that is normally also used for electronic components, are also suitable for mass production, it is also effective in that respect.
[0053]
The embodiment is described for facilitating the understanding of the present invention, and does not limit the present invention.
For example, in the present embodiment, the channel plate is made of an aluminum alloy. However, pure aluminum may be used as a material, or any material having substantially the same properties as those of aluminum or aluminum alloy may be used. It can be a material. Although the channel plate is manufactured by the die casting method, for example, a part or the whole may be manufactured by machining.
[0054]
Further, the shape of the flow path plate is not limited to this embodiment. The shape of the channel plate are various, but it is effective to make the stress at the time of expanding the cross-sectional area as small as possible to decrease. Such a structure of the line head when the thickness of the channel plate shown in Figure 11. In the line head shown in FIG. 11, the thickness h of the head portion is about 5.3 mm. In addition, with such a structure, it is possible to increase the structural strength by applying a more sufficient adhesive to the vacant gap, which is effective.
[0055]
【The invention's effect】
As described above, according to the present invention, there is provided a line head in which ink ejection holes are arranged over a long section, and in particular, an ink jet head which appropriately radiates heat and prevents the occurrence of a defect caused by heat, and a method of manufacturing the same. can do.
In addition, as a print head, a printer device that includes an inkjet head type line head that appropriately dissipates heat and prevents occurrence of a defect due to heat, thereby enabling high-quality printing at a high speed. Can be provided.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating an external appearance of a main body of an inkjet printer according to an embodiment of the present invention.
FIG. 2 is a diagram for explaining a schematic configuration of the ink jet printer shown in FIG. 1;
FIG. 3 is a diagram for explaining a paper transport mechanism of the ink jet printer shown in FIG. 1;
FIG. 4 is a diagram illustrating a configuration of a print head cartridge of the ink jet printer illustrated in FIG. 1;
Figure 5 is a first diagram showing a configuration of the print head cartridge of the line head shown in FIG.
FIG. 6 is a second diagram illustrating the configuration of the line head of the print head cartridge illustrated in FIG. 4;
Figure 7 is a diagram showing, in disassembled main part of the head portion of the print head cartridge for explaining the print head cartridge shown in FIG.
Figure 8 is a diagram for explaining the arrangement of the ink discharge hole and the opening of the nozzle sheet of the line head shown in FIGS.
Figure 9 is a diagram for explaining the arrangement of the heater chip and dummy chip of the line head shown in FIGS.
Figure 10 is a diagram showing a configuration of a flow path plate line head shown in FIGS.
Figure 11 is a diagram showing the configuration of the line head of a modification of the present embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Ink jet printer, 10 ... Paper conveyance mechanism, 11 ... Pickup roller, 12 ... Separation roller, 13 ... Guide member, 14 ... Reversing roller, 15 ... Auxiliary roller, 16 ... 1st guide plate, 17 ... Conveying belt, 18 , 19 ... drive roller, 20 ... pinch roller, 21 ... second guide plate, 22 ... tension control roller, 23 ... reversing guide plate, 24 ... reversing conveyance roller, 25 ... cap retreat place, 30 ... print head cartridge Reference numerals 31, head part, 32, ink tank part, 33, cartridge case, 34, cap, 35, line head, 40, main body, 41, lid, 42, paper feed cassette, 43, paper discharge tray, 44, operation panel , 310 ... nozzle sheet, 311 ... ink discharge port, 312 ... wire opening, 321 ... heating element, 322 ... heater chip, 3 3, dummy chip, 324, ink flow path lower layer, 325, heater chip end, 330, flow path plate, 331, ink flow path, 334, gap for mounting B terminal board, 335, ink supply through hole, 336 ... Ink supply pipe, 337 ... Ink channel groove, 338 ... Notch, 341 ... B terminal plate, 342 ... Gold wire, 343 ... Seal resin, 344 ... Connector pin, 350 ... Head frame, 351 ... Line head Arrangement opening, 360 ... Printed circuit board

Claims (9)

A plurality of ink ejection nozzles,
Provided corresponding to said ink ejection nozzle, a heating member for ejecting the ink from the ink discharge nozzles,
An ink jet head comprising: a member formed of aluminum or an aluminum alloy that is in direct or indirect contact with the heat generating member, the flow path forming member forming an ink flow path that supplies ink to each of the ink discharge nozzles. The contact surface between the ink in the flow path forming member, the ink-jet head according to claim 1 in which the resin film is formed. The inkjet head according to claim 2, wherein the resin film is a polyimide vapor-deposited film. The ink jet head according to claim 1 a plurality of ink discharge nozzles are arranged line head straight. A plurality of ink ejection nozzles are arranged at a predetermined pitch,
In correspondence with the ink ejection nozzles, providing a heat generating member for ejecting ink from the ink discharge nozzles,
Manufacture of an ink jet head in which a flow path forming member formed of aluminum or an aluminum alloy and forming an ink flow path for supplying ink to each of the ink discharge nozzles is disposed so as to be in direct or indirect contact with the heat generating member. Method. Forming a resin film on the contact surface of the flow path forming member and the ink,
7. The method according to claim 6, wherein the flow path forming member on which the resin film is formed is disposed such that a surface on which the resin film is formed constitutes an ink flow path surface. The resin film, ink jet head manufacturing method according to claim 6, wherein the polyimide deposition film by depositing a polyimide resin. A plurality of ink ejection nozzles, a heating member provided corresponding to the ink ejection nozzle, for ejecting ink from the ink ejection nozzle, and a member formed of aluminum or an aluminum alloy that comes into direct or indirect contact with the heating member printer having an ink jet head having a flow path forming member comprising a forming an ink flow path for supplying ink to each of the ink ejection nozzle. 9. The printer device according to claim 8, wherein the inkjet head is a line head in which the plurality of ink ejection nozzles are linearly arranged over the entire printing width.

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