JP2002086730A - Liquid jet recording head and liquid jet recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a difference in an ink supplying characteristic for supplying ink from a tank between ejection sections for identical colors or colors having similar characteristics. SOLUTION: An ink supplying unit after being assembled is so constituted that inks supplied from supplying holes 41Y, 41M, 41C, 41B corresponding to joint sections to be connected to supplying holes of the ink tanks for yellow, magenta, cyan and black are supplied to six ejection sections 4C, 4M, 4Y, 4M, 4C, 5B on a recording head section through an ink supply passage (the portion drawn by dotted line in the figure) formed of the ink supplying section 41 and an ink supply passage forming assembly 42. The ink supply passage from the supply hole 41C corresponding to the joint section of the tank for cyan to the identical two cyan ejection sections 4C is divided into two passages in the way as in the magenta case and the lengths of the passages after divided are equal to each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid discharge recording head for applying a plurality of different types of liquids, such as inks of a plurality of colors, to a recording medium, such as paper, and more particularly, to scanning a recording head bidirectionally. The present invention relates to a liquid discharge recording head used in a bidirectional printing apparatus that performs recording.

[0002]

2. Description of the Related Art In a printing apparatus, in particular, an ink jet type printing apparatus, improvement of a recording speed in color printing is an important theme. As a method of improving the recording speed, in addition to increasing the length of the recording head, generally, the recording (driving) frequency of the recording head is improved, and bidirectional printing is performed. Compared with one-way printing, bi-directional printing is time-dependent in dispersing required energy when obtaining the same throughput, and thus is a cost-effective means as a total system.

As a configuration of a liquid discharge recording head for solving the above-mentioned problem, Japanese Patent Application Laid-Open No. 58-179653 discloses a configuration in which a forward nozzle and a backward nozzle are prepared. In this publication, the use head (ejection unit) is switched between the forward pass and the return pass so that the driving order of each color becomes the same. The configuration of the recording head unit is Y (yellow), M (magenta), C (cyan),
This is a combination of recording heads that eject each ink of Bk (black). Specifically, FIG.
As shown in (1), the heads are arranged in the order of Bk, C, M, Y, M, C, and Bk in both the forward scan and the backward scan. The ink is supplied to each head from each color ink tank via a pipe for each head.

[0004]

SUMMARY OF THE INVENTION However, Japanese Patent Application Laid-Open
In the configuration disclosed in Japanese Patent Application No. 58-179653, there is a need to secure a space by crawling the ink supply pipe and to remove bubbles in the pipe, and thus there is a problem that the apparatus becomes large.

To reduce the size, consider a configuration in which an ink tank is mounted for each head, the head and the ink tank are mounted on a carriage, and bidirectional scanning is performed with the arrangement of the respective color discharge units as described in the above-mentioned publication. Looking at the problem, the size of the device is increased due to the increase in size and weight of the carriage,
Depending on the configuration, there is a problem that the number of parts increases and the cost increases. Further, when a plurality of ink tanks are used for the same color, the number of ink tanks required in the initial operation is large, so that the initial investment increases. Further, in this case, when any one of the plurality of ink tanks of the same color becomes empty and needs to be replaced, there is a problem that it is difficult for the user to simply understand which tank is to be replaced.

Further, in order to solve the above-mentioned problem, if a single tank for supplying liquid to a discharge section discharging the same color is provided, a liquid supply path from one tank to a discharge section of the same color may be branched on the way. Therefore, there is a concern that the ink supply characteristics and the ink discharge characteristics may differ between the discharge units of the same color.

That is, a resistance component of pressure (pressure loss: determined by a supply path length, a supply path cross-sectional area, a maximum flow velocity, an ink viscosity, and the like) generated by an ink flow from an ink tank to each ejection portion at the time of ink supply. If it is increased, printing may be affected. Also, if there is a large difference in pressure loss to each discharge unit, the ink discharge characteristics may differ for each discharge unit, or a large difference may occur in the removability of bubbles in the supply path. Small things are desired.

Accordingly, an object of the present invention is to provide a head and an ink tank on a carriage in order to reduce the size of a bidirectional printing apparatus, so that a single tank can be used for a discharge unit of the same color. It is an object of the present invention to provide a liquid discharge recording head and a liquid discharge recording apparatus in which a difference in ink supply characteristics from a tank between discharge units of the same color or colors having similar characteristics is small.

[0009]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a plurality of ejection port arrays for individually ejecting a plurality of types of liquids, and an ink port mounted on a carriage and provided with an ink port. An ink tank provided corresponding to the plurality of types of liquids for supplying the liquid, and a liquid supply path for supplying the liquid in the ink tank to the discharge port array. A liquid outlet recording head provided with a plurality of liquid outlets for each of the at least one liquid outlet, wherein at least one liquid outlet is provided. The liquid supply paths to the plurality of discharge port arrays are provided with equivalent liquid supply characteristics among the plurality of discharge port arrays.

The present invention is also directed to a plurality of ejection port arrays for individually ejecting a plurality of types of liquids and the plurality of liquids mounted on a carriage and supplying ink to the ejection port arrays. A liquid supply path for supplying the liquid in the ink tank to the discharge port array, wherein the ink tank is provided with a liquid outlet communicating with the liquid supply path for each liquid. Wherein the ejection port array is a plurality of liquid ejection recording heads provided for at least one liquid outlet, and a liquid supply path to a plurality of ejection port arrays for ejecting one type of liquid is provided. It is characterized by having equivalent liquid supply characteristics between the discharge port arrays and also having equivalent liquid supply characteristics between the discharge port arrays of each type of liquid.

In each of the inventions described above, the carriage is bidirectionally scanned with respect to the recording medium, and the ejection port array corresponding to one or all kinds of liquids is moved in the carriage scanning direction. Are preferably arranged symmetrically with respect to. According to this configuration, it is possible to eliminate color unevenness due to the order in which recording droplets are ejected during bidirectional printing.

Further, it is preferable that the connection position of the liquid supply path to the ejection port array corresponding to one or all kinds of liquids is line-symmetric.

In addition, the present invention provides a liquid discharge recording apparatus which has a liquid discharge recording head as described above, and which performs recording on a recording medium by discharging liquid droplets from a desired discharge portion as a carriage scans. Also features.

As described above, the liquid discharge recording head of the present invention includes a recording element having a plurality of discharge port arrays for receiving liquid supply from a tank for each type of liquid, and discharge ports for corresponding types of liquid. There are supply paths branched in the middle according to the number of rows, and the liquid supply characteristics of these supply paths are almost equal to the discharge port row of the same type of liquid.

According to such a liquid discharge recording head,
Since one tank is installed for each type of liquid, the size of the carriage can be reduced, and replacement of the tank when the liquid is consumed is the same operation as a conventional print head that is not symmetrically arranged. Operation that is easy for the user to understand is possible.

Further, a resistance component of pressure (pressure loss: determined by a supply path length, a supply path cross-sectional area, a maximum flow velocity, an ink viscosity, and the like) generated by a liquid flow from a tank to each discharge port array at the time of liquid supply. Almost the same can be achieved between discharge port arrays of the same type of liquid. As a result, the liquid ejection characteristics for recording and the removability of bubbles in the supply path can be made uniform between the ejection ports of the same type of liquid.

In addition, when arranging the branch portion in the supply path, it is not preferable to easily increase the number of constituent members in view of costs. Therefore, similarly to the conventional print head, a member having a joint portion with the tank and the print head are used. It is desirable to form the supply path by joining the part and the member to be joined.

When the ejection port arrays are not arranged symmetrically and, for example, the ejection port arrays for ejecting black ink are provided separately from the color ejection port array groups arranged symmetrically, the ejection from the corresponding tank is not performed. It is not necessary to include a branch part in the supply path.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 1 is an assembled perspective view showing a recording head cartridge as an example of a liquid discharge recording head according to the present invention. FIG. FIG. 3B is a perspective view of the cartridge as viewed from the tank mounting side, and FIG. 3C is a perspective view of the cartridge with the tank removed.

The head cartridge 1 of the embodiment shown in FIG.
Is composed of a recording unit 2 and an ink supply unit 3. The recording unit 2 performs recording on a recording head unit having a color recording element 4 for three colors of cyan (C), magenta (M), and yellow (Y) and a recording element 5 for black (Bk), and a recording apparatus described later. When the head cartridge 1 is mounted, the electrical connection portion 6 electrically connected to the electrical connection portion of the recording apparatus, and the electrical connection portion 6 and the contact pads (not shown) of the two recording head portions are electrically connected. And a flexible wiring board 7 to be connected. On the other hand, the ink supply unit 3 includes a holder section 8 for holding ink tanks 9a to 9d of four independent colors (C, M, Y, and Bk), and an ink supply path from the ink tank 9 for each color to a corresponding ejection port array. Supply path forming assembly (not shown) for forming ink
And

"Recording Head" First, the recording head of this embodiment will be described in detail. FIGS. 2A and 2B are explanatory views schematically showing a main part of a color recording element of a recording head portion of the recording unit shown in FIG. 1, wherein FIG.
(B) is a diagram for explaining the arrangement of the discharge ports, and (c) is a cross-sectional view.

As described above, the recording head of this embodiment includes the color recording elements 4 for cyan (C), magenta (M), and yellow (Y) and the recording element 5 for black.

As shown in FIG. 2C, these recording elements include a substrate 17 including a heat-generating resistor element 15 as an energy conversion element, and an orifice plate 16 forming an ejection port 11. . The substrate 17 has a plane orientation <
100>, a plurality of rows of a plurality of heating resistance elements 15, a driving circuit 13 for driving the heating resistance elements 15 in each row, and a contact pad 19 for connection to the outside are formed on a substrate 17. , A wiring 18 for connecting the drive circuit 13 and the contact pad 19 and the like are formed using a semiconductor process. Further, the substrate 17 is provided with five through-holes formed by anisotropic etching in a region excluding the circuit 13, the element 15, the wiring 18, and the like, and discharge port arrays 21 to 23, 31 described later, respectively. To 33 are provided with ink supply ports 12 and 12a for supplying liquid. FIG. 2A schematically shows a state in which a substantially transparent orifice plate 16 is formed on the substrate 17, and the above-described heating resistor element and ink supply port are omitted.

The orifice plate 16 provided on the substrate 17 is formed of a photosensitive epoxy resin, and the discharge port 11 and the liquid flow path 10 are formed by photolithography in correspondence with the heating resistor 15 described above. I have.

Such a recording element performs recording by discharging a liquid such as ink from the discharge port 11 by utilizing the pressure of bubbles generated by film boiling due to heat energy applied by the heating resistance element 15. . In the recording element, by connecting the contact pad 9 to a flexible wiring board (see reference numeral 13 in FIG. 1), an electric connection portion (see reference numeral 6 in FIG. 1) connected to the wiring board makes an electrical connection of a recording device described later. When connected to the connection unit, a drive signal or the like can be received from the recording device. Further, the ink supply ports 12, 12a and the like of the above-described recording elements are connected to ink tanks of each color via an ink supply path forming assembly described later.

Further, in the color recording element 4 of the present embodiment, a plurality of ejection ports 11 are provided and arranged at a predetermined pitch, so that ejection port arrays (ejection sections) 21 substantially parallel to each other. To 23, 31 to 33 are formed. Here, in FIG. 2A, the i-th discharge port from the drawing of each of the discharge port arrays 21 to 23 coincides with the arrow direction shown in FIG. 2A. In this manner, the ejection port arrays 21 to 23 are arranged such that the corresponding ejection ports are coincident with each other in the scanning direction when this recording element is mounted on a recording apparatus or the like to be described later and scanned. One discharge port array group 20 is formed. Discharge port rows 31-33
Are arranged in the same manner as the ejection port arrays 21 to 23, and the first ejection port row group 20
The second ejection port row group 30 is formed so as to be adjacent to.

With respect to the six ejection port arrays of these two ejection port array groups, cyan (C) is used in the outermost ejection port arrays 23 and 33, and magenta (M) is used in the ejection port arrays 22 and 32.
However, it is assumed that yellow (Y) is discharged from the innermost discharge port arrays 21 and 31 adjacent to each other. Therefore, the yellow ink is supplied to the ink supply port 12a (the ink supply port provided at the center) by the ink supply port 12a adjacent to the ink supply port 12a.
Magenta ink is supplied to one of the ink supply ports 12, and cyan ink is supplied to the two outermost ink supply ports 12 from Y, M, and C independent ink tanks. Thus, the central ink supply port 12a supplies liquid to the two ejection port arrays 21 and 31,
The ink supply port 12a and the liquid flow path 10a function as a common liquid chamber of the two ejection port arrays 21 and 31.

As described above, the ejection port arrays for ejecting the same type of liquid are arranged in the portion where the two ejection port array groups are adjacent to each other, and the other ejection port arrays of the same type and their driving are arranged around this portion. By arranging the circuits substantially symmetrically, the through-holes serving as the ink supply ports 12 and 12a, the drive circuits and the heat-generating resistance elements, etc. can be arranged at equal intervals with respect to the substrate without waste, and the substrate size can be reduced. . In addition, by arranging the ejection port arrays for ejecting the same kind of liquid in line symmetry, the order of ink ejection (ejection) for one pixel for forming a desired color on the recording medium is the forward scan and the backward scan. Therefore, the color is uniform regardless of the scanning direction, and the occurrence of color unevenness due to reciprocal printing can be prevented.

Further, in this color recording element, FIG.
As is clear from (a) and FIG. 2 (b), the first ejection port array group 20 and the second ejection port array group 30 are formed by ejection port arrays 21 to 23 forming respective ejection port groups. , 31-33 are arranged offset from each other in the arrangement direction of the ejection ports so as to complement each other in the scanning direction described above. As shown in FIG. 2B, in the present embodiment, in each of the ejection port arrays forming the first ejection port row group and the second ejection port row group, 128 ejection ports have t1 = t2 = About 40 μm (1 /
(600 inches). The arrangement of the ejection port arrays 21 and 31 is exactly the same as the pitch of the ejection port array with respect to the sub-scanning direction of the print head (in this example, it matches the arrangement direction of the ejection port arrays). Shifted by 1/2 (t3 = 1 / 2t1 = about 2
0 μm). Thereby, the actual 1200d
High definition mode printing of pi (1200 dots per inch) can be performed.

On the other hand, in the recording element for black, since black is generally used only in a single color, it is not necessary to arrange it symmetrically. Further, in order to improve the printing speed in monochrome printing, a larger number of nozzles are provided than heads of other colors. In the present embodiment, the ejection port arrays 40 and 41 for Bk are the ejection port arrays 2 of the above-described color printing element.
Similarly to the nozzles 1 and 31, the ejection ports are arranged so as to complement each other in the scanning direction, and printing can be performed in the sub-scanning direction at a density twice the nozzle array density of each ejection port row. It has become.

[Ink Channel Forming Assembly] Next, the ink supply path forming assembly of the ink supply unit will be described. It is possible to supply ink in the ink tanks for yellow, magenta, cyan, and black mounted on the holder of the ink supply unit to each of the ink supply ports of the color and black recording elements as described above. Therefore, in the present embodiment, an ink supply path forming assembly that connects the tank and the ink supply ports of the recording element is provided in the ink supply unit.

In particular, as described above, the color recording element has a structure in which ejection port arrays for ejecting the same kind of liquid are arranged in line symmetry, and a yellow ink supply port is provided at the center portion, and a magenta ink supply port is provided at both sides thereof. Since the supply ports are further provided symmetrically with cyan ink supply ports on both outer sides,
An ink supply path that connects each of the three color tanks with the corresponding color ink supply port branches in the middle. Further, in order to make the ink supply characteristics the same between the same type of nozzles, the ink paths after branching are equivalent.

Hereinafter, a specific configuration of such an ink supply path forming assembly will be described.

FIG. 3 is an exploded perspective view for explaining an ink supply path forming assembly provided in the ink supply unit of the head cartridge shown in FIG.

As shown in FIG. 3, the head cartridge 1 is composed of a recording unit 2, a joint seal member 40, an ink supply path forming assembly 42, and an ink supply unit 3 provided with an ink supply unit 41.

A joint seal member 40 is provided between the recording unit 2 and the ink supply path forming assembly 42 to prevent ink from leaking from the connection between the ink supply path communicating with the tank and the ink supply port of the recording element. Attached to. The ink supply path is formed by ultrasonically welding the ink supply section 41 and the ink supply path forming assembly 42. Further, the recording unit 2 and the ink supply unit 3 hold the ink supply path forming assembly 42 and the joint seal member 40 with the screw boss 4 in the ink supply unit 41 interposed therebetween.
4 are fixed by fixing screws 43. Thus, the ink supply unit 41 and the ink supply path forming assembly 4
It is possible to suppress the application of a stress in the direction of peeling to the joint portion with 2 and to use the screw 43 to facilitate disassembly for recycling or the like. At the same time, the recording unit 2 is accurately positioned and fixed with respect to the reference positions of the ink supply unit 3 in the X, Y, and Z directions.

FIGS. 4A to 4C are component diagrams showing the positional relationship among the ink supply unit, the ink supply path forming assembly, and the recording head shown in FIG.

In the recording head portion shown in a top view in FIG. 4A, a color recording element 4 has a yellow discharge port array 4Y and two magenta discharge ports arranged line-symmetrically on both outer sides thereof. Outlet row 4M and outermost yellow discharge port row 4Y
Cyan ejection opening arrays 4C arranged symmetrically with respect to the center.
And the black recording element 5 is a black ejection port array 5B.
have. Note that the six discharge port arrays 4C, 4M, 4
The specific configuration of Y, 4M, 4C, and 5B is as described above with reference to FIG.

The recording head portion shown in FIG. 4A is superimposed on the upper surface of the ink supply path forming assembly 42 shown in FIG. 4B.
The supply ports 42C, 42M, 42Y, 42 correspond to the positions of the discharge port arrays 4C, 4M, 4Y, 4M, 4C, 5B.
M, 42C and 42B are formed. Supply ports 42 for two cyan and magenta discharge port arrays respectively
C and 42M are arranged symmetrically with respect to the yellow supply port 42Y.

Further, the ink supply path forming assembly 42 shown in FIG. 4B is superimposed on the ink supply section 41 of the ink supply unit 3 shown in FIG. 4C. The supply ports 41Y, 41M, and 41 correspond to the positions of the joints joined to the outlets of the ink tanks of M, C, and B (see reference numeral 50 in FIG. 1C).
C and 41B are formed.

FIG. 5 is a perspective view after the components shown in FIG. 4 have been assembled. As shown in this figure, the ink supply unit after assembly has ink outlets 50 for yellow (Y), magenta (M), cyan (C), and black (Bk) ink tanks.
Supply port 4 corresponding to the joint part (not shown) that joins
The ink supplied from 1Y, 41M, 41C and 41B is supplied to an ink supply path formed by the ink supply section 41 and the ink supply path forming assembly 42 (the dotted line in FIG. 5).
, The six ejection port arrays 4C, 4M,
4Y, 4M, 4C, and 5B.

At this time, the number of ink supply paths from the supply port 41Y corresponding to the joint portion of the yellow tank to the yellow discharge port array 4Y is the same for black as well. The ink supply path from the supply port 41C corresponding to the joint portion of the cyan tank to the same two cyan ejection port arrays 4C is as follows.
Magenta is similar, but is branched into two on the way.

Further, the above-described ink supply path is formed on a plane sandwiched between the ink supply section 41 and the ink supply path forming assembly 42. And two or more (two in this example)
The ink supply path branched into the same type of ink ejection port row is branched symmetrically on this plane (in this example, line symmetric about the yellow ejection port row 4Y), and the flow path length after branching is equal to each ejection port. It is assumed that they are equal in columns (see FIGS. 4B and 4C).

As a result, the resistance component of the pressure generated by the ink flow from the ink tank to each ejection port array during ink supply (pressure loss: the supply path length, the supply path cross-sectional area, the maximum flow velocity, the ink viscosity, etc. Determined) can be made almost the same between the ejection port arrays of the same color. As a result, the ink ejection characteristics and the removability of bubbles in the supply path can be made uniform between the ejection port arrays of the same color. Depending on the connection position of the supply path to the discharge port row, it is difficult to remove defective supply or bubbles remaining inside, so the supply path is not limited to this embodiment, and the supply path is arranged near the center of the discharge port row. It is desirable to do. However,
Depending on the arrangement of the ink supply passages, it may be difficult to arrange them near the center.In this case, the supply port position is the same between the discharge port rows of the same color with respect to the discharge port row, and each supply port position is also line-symmetric. By doing so, it is possible to suppress a difference in the ejection state between the forward scan and the backward scan.

The pressure loss from the joint portion of the ink tank of each color to the corresponding discharge port array is determined by dividing the flow path length before the branch section and the flow path length after the branch section when the cross-sectional shape of the flow path is equal. Since the ink supply path is simply obtained by the sum of the lengths divided by the number, the ink supply paths are arranged so that the difference in the lengths is as small as possible.

When it is difficult to equalize the pressure loss due to the flow path length, the cross-sectional area of a part or the whole of the ink supply path is made different from that of the other ink supply paths, so that the pressure loss of the supply path to each ejection port array is reduced. Can be adjusted.

FIG. 13 shows a supporting substrate of the color recording element and the black recording element in FIG. In FIG.
Reference numeral 1 denotes a supply groove corresponding to the black liquid chamber of the black recording element, and a through hole 61a connected to the black supply port 42B shown in FIG. 4B is formed in the groove. Similarly, reference numeral 62 denotes a supply groove corresponding to the cyan liquid chamber of the color recording element, reference numeral 63 denotes a supply groove corresponding to the magenta liquid chamber, reference numeral 64 denotes a supply groove corresponding to the yellow liquid chamber, and reference numerals 62a, 63a, and 64a denote the supply grooves. The through holes connected to the cyan supply port 42C, the magenta supply port 42M, and the yellow supply port 42Y of FIG. 4B are shown. Such a correspondence is the same in other embodiments described below.

The embodiment will be described in more detail. The configuration for supplying ink to the ejection port array for ejecting one color is usually as shown in FIG. The ink supplied from an ink tank (not shown) passes through the supply path 47 and is introduced into the supply groove 12 which is a common liquid chamber via the supply path connection part 42. Further, ink is supplied to each of the ejection ports 20 and 30 via the common liquid chamber 12. When one color is supplied to a plurality of ejection port arrays, as shown in FIG. 15, the supply path 47 includes one common supply path 47a to which ink is supplied from one ink tank and the number of ejection port arrays 21 and 31. And the number of individual supply paths 47b branched by the branching section 47c. As shown in FIG. 16, in the configuration after the supply path connection portion corresponding to each ejection port array, ink is introduced into the supply groove 12 through the supply path connection portion 42 in the same manner as in the above-described normal configuration, and the common liquid chamber is formed. Ink is supplied to each of the ejection ports 20 and 30 through the nozzle 12. In the present embodiment, the yellow discharge port array located at the center of the independently arranged black discharge port row and the symmetrically disposed discharge port row has the same supply path configuration as the conventional one. As for magenta, the common supply path 47a has two individual supply paths 4 on the way.
7b. And each supply path connection part 42
It is symmetrical with respect to a line connecting the two branch portions 47c and one supply path connecting portion 42.

By making the volumes, pressure losses, and the like of the plurality of individual supply paths for supplying a plurality of discharge port arrays for discharging the same color ink equal to each other, the removability of residual bubbles in the supply paths and the ink discharge characteristics are improved. It does not vary for each ejection port array, so that unevenness during reciprocating printing and good recoverability can be obtained.

Further, by making the angle of entry of the common supply path to each individual supply path at the branch portion equal, the influence of inertia caused by the inflow of ink can be made equal.

Furthermore, by making the section from the branch section to the supply path connection section symmetrical with respect to a plane perpendicular to the line connecting the two supply path connection sections and bisecting the two, it is easy to equalize the pressure loss and the volume. Become.

As shown in FIG. 17, even when the ejection port array is not 90 ° with respect to the scanning direction and when the positions of the symmetry planes are different from each other, the same supply path configuration can be used to provide a uniform recovery. A good head cartridge can be provided.

(Second Embodiment) In this embodiment, the configuration of the recording unit is the same as that of the first embodiment, but the configuration of the ink supply path formed in the ink supply unit is different. I have. Therefore, only a configuration example of the ink supply path different from that of the first embodiment will be described here.

FIGS. 6A to 6C are component diagrams showing the positional relationship between the ink supply unit, the ink supply path forming assembly, and the recording head shown in FIG. 3, and FIG. FIG. 4 is a perspective view after assembling the components shown in FIGS.

As shown in this figure, the ink supply unit 3 after the assembly is connected to a supply port of an ink tank for yellow (Y), magenta (M), cyan (C), and black (Bk). Supply port 41 corresponding to (not shown)
The inks supplied from Y, 41M, 41C and 41B are
Ink supply unit 41a and ink supply path forming assembly 42
a through the ink supply path (the dotted line portion in FIG. 6) formed by the ink ejection paths 4C, 4M, 4Y,
4M, 4C, and 5B.

At this time, the number of ink supply paths from the supply port 41Y corresponding to the joint portion of the yellow tank to the yellow discharge port array 4Y is the same for black as well. The ink supply path from the supply port 41C corresponding to the joint portion of the cyan tank to the same two cyan ejection port arrays 4C is as follows.
Magenta is similar, but is branched into two on the way.

The ink supply path is formed on a plane sandwiched between the ink supply section 41a and the ink supply path forming assembly 42a. And two or more (in this example, 2
The ink supply paths branching into the same type of ink ejection port row are branched on this plane in line symmetry (in this example, line symmetry centering on the yellow ejection port row 4Y), and the flow path length after branching is It is assumed that the discharge port arrays are equal (see FIGS. 6B and 6C).

Further, as for the cyan, magenta, and yellow liquids having similar liquid characteristics, the flow path lengths before the branch portion are also equal between the respective colors as compared with the first embodiment (FIG. 6B, (C) and (d)).

As a result, the resistance component of the pressure generated by the ink flow from the ink tank to each ejection port array at the time of ink supply (pressure loss: supply path length, supply path cross-sectional area, maximum flow velocity, ink viscosity, etc. (Determined) can be made almost the same not only between the ejection port arrays of the same color but also between the ejection port arrays of colors having similar characteristics. As a result, the ink ejection characteristics and the removability of bubbles inside the supply path can be made uniform between the ejection port arrays of the same color and a color having similar characteristics.

(Third Embodiment) In this embodiment,
Although the configuration of the recording unit is the same as that of the first embodiment, the formation mode of the ink supply path formed in the ink supply unit is different. Therefore, only the formation of the ink supply path different from that of the first embodiment will be described here.

FIG. 7 is an exploded perspective view for explaining an ink supply path forming assembly provided in the ink supply unit of the head cartridge shown in FIG.

As shown in FIG. 7, the head cartridge 1 is constructed by assembling the recording unit 2, the joint seal member 40, the ink supply path forming assemblies 42b1 and 42b2, and the ink supply unit 3 provided with the ink supply section 41b. Become.

A joint seal member 40 is provided between the recording unit 2 and the ink supply path forming assembly 42 to prevent ink from leaking from a connection between the ink supply path communicating with the tank and the ink supply port of the recording element. Be attached.
The ink supply path is formed by ultrasonically welding the ink supply section 41b and the ink supply path forming assemblies 42b1 and 42b2. The recording unit 2 and the ink supply unit 3 are connected to the ink supply path forming assemblies 42b1 and 42b1.
The screw 43 is fixed to a screw boss 44 in the ink supply unit 41b so as to sandwich the joint seal member 40 with the joint seal member 2b2. This allows the ink supply unit 41
b and ink supply path forming assemblies 42b1 and 42b2
It is suppressed from the force in the direction of peeling off the joint, and the use of the screw 43 achieves easy decomposability. At this time, the recording unit 2 simultaneously moves the ink supply unit 3 in the X and Y directions.
It is accurately positioned and fixed with respect to the reference position in the Z direction.

FIGS. 8A to 8D are component diagrams showing the positional relationship among the ink supply unit, the ink supply path forming assembly, and the recording head shown in FIG.

In the recording head portion shown in a top view in FIG. 8A, a color recording element 4 has a yellow discharge port array 4Y and two magenta discharge ports arranged line-symmetrically on both outer sides thereof. Outlet row 4M and outermost yellow discharge port row 4Y
Cyan ejection opening arrays 4C arranged symmetrically with respect to the center.
And the black recording element 5 is a black ejection port array 5B.
have. Note that the six discharge port arrays 4C, 4M, 4
The specific configuration of Y, 4M, 4C, and 5B is as described above with reference to FIG.

The recording head portion shown in FIG. 8A is overlaid on the upper surface of the ink supply path forming assembly 42b2 shown in FIG.
2 includes six discharge port arrays 4C, 4M, 4Y, 4M, 4
Supply ports 42C2, 42 so as to correspond to the positions of C and 5B.
M2, 42Y2, 42M2, 42C2, 42B2 are formed. Two cyan and magenta supply ports 42
C2 and 42M2 are arranged symmetrically with respect to the yellow supply port 42Y2.

Further, the ink supply path forming assembly 42b2 shown in FIG. 8B is superimposed on the upper surface of the ink supply path forming assembly 42b1 shown in FIG. 8C. Supply ports 42M2, 4 formed in supply path forming assembly 42b2
Supply ports 42M1, 42Y1, 42M1, and 42B1 are formed to correspond to the positions of 2Y2, 42M2, and 42B2. In addition, the ink supply path forming assembly 42b
1, a magenta supply port 42C1 is formed so as to correspond to the position of the supply port 41C shown in FIG.

Further, the ink supply path forming assembly 42b1 shown in FIG. 8C is mounted on the ink supply section 41b of the ink supply unit 3 shown in FIG. , M, C, and B are provided with supply ports 41Y, 41M, 41C, and 41B so as to correspond to the positions of the joints that join the outlet ports 50 of the ink tanks of the respective colors.

FIG. 9 is a perspective view after the components shown in FIG. 8 have been assembled. As shown in this figure, the ink supply unit after assembly has ink outlets 50 for yellow (Y), magenta (M), cyan (C), and black (Bk) ink tanks.
Supply port 4 corresponding to the joint part (not shown) that joins
The ink supplied from 1Y, 41M, 41C, and 41B passes through the ink supply path formed by the ink supply section 41b and the ink supply path forming assemblies 42b1 and 42b2 (the dotted line section in FIG. 9), and the recording head section. Are supplied to the six discharge port arrays 4C, 4M, 4Y, 4M, 4C, and 5B.

At this time, the number of ink supply paths from the supply port 41Y corresponding to the joint portion of the yellow tank to the yellow discharge port array 4Y is the same for black as well. The ink supply path from the supply port 41C corresponding to the joint portion of the cyan tank to the same two cyan ejection port arrays 4C is as follows.
Magenta is similar, but is branched into two on the way.

More specifically, the above-described ink supply paths for yellow, black and magenta are formed on a plane sandwiched between the ink supply section 41b and the ink supply path formation assembly 42b1, and the ink supply path formation assembly 42b1 and the ink supply path The ink supply path for cyan is formed on a plane sandwiched between the forming assemblies 42b2. An ink supply path that branches into two or more (two in this example) same-type ink ejection port arrays branches in a line symmetric manner (in this example, line symmetry centering on the yellow ejection port array 4Y) on the above plane. The length of the flow path after branching is assumed to be equal in each discharge port array (FIG. 8).
(B), (c) and (d)). Thus, the resistance component of the pressure generated by the ink flow from the ink tank to the respective ejection port arrays at the time of supplying the ink can be made almost the same between the ejection port arrays of the same color. As a result, the ink ejection characteristics and the removability of bubbles in the supply path can be made uniform between the ejection port arrays of the same color.

Further, in the present embodiment, a plurality of ink supply paths which need to be branched into two or more arrays of the same kind of ink are formed on a plurality of planes, respectively.
A configuration in which the degree of freedom in the layout of the ink supply paths is high.

However, in this configuration, since the ink supply path forming assemblies 42b1 and 42b2 are stacked on the ink supply section 41b of the ink supply unit 3, the recording head section existing in the ink supply path forming assembly 42b2 Supply ports (42C2, 42
M2, 42Y2, 42M2, 42C2, 42B2) may differ depending on the joining accuracy of each product. Therefore, the variation in the height of the supply port is adjusted by the compression dimension of the joint seal member 40 when joining with the recording unit 2, and the connection between the ink supply path communicating with the tank and the ink supply port of the recording element is adjusted. The state is stabilized between products.

(Fourth Embodiment) In this embodiment,
Although the configuration of the recording unit is the same as that of the first embodiment, the formation mode of the ink supply path formed in the ink supply unit is different. Therefore, only the formation of the ink supply path different from that of the first embodiment will be described here.

FIGS. 10A to 10D are component diagrams showing the positional relationship among the ink supply unit, the ink supply path forming assembly, and the recording head unit constituting the head cartridge shown in FIG.

In the recording head portion shown in a top view in FIG. 10A, a color recording element 4 has a yellow discharge port array 4Y and two magenta discharge ports arranged symmetrically on both outer sides thereof. Outlet row 4M and outermost yellow discharge port row 4
Two cyan ejection port arrays 4 arranged symmetrically with respect to Y
C, and the black recording element 5 is
B. Note that the six discharge port arrays 4C, 4M, 4
The specific configuration of Y, 4M, 4C, and 5B is as described above with reference to FIG.

The recording head shown in FIG. 10A is overlaid on the upper surface of the ink supply path forming assembly 42c2 shown in FIG. 10B.

Further, the ink supply unit 4 shown in FIG.
The ink supply path forming assembly 42c1 shown in FIG. 10D is overlaid on the upper surface of 2c.

Further, the ink supply path forming assembly 42c2 shown in FIG. 10B is attached to the ink supply section 41c of the ink supply unit 3 shown in FIG. 10C.
The supply ports 41Y1, 41M1, 41C1, and 4C are provided in the ink supply section 41c so as to correspond to the positions of the joints connected to the outlets 50 of the ink tanks of Y, M, C, and B colors.
1B1 is formed.

Further, the supply ports 41C2, 41M2, 41Y2, 4Y are provided in the ink supply section 42c so as to correspond to the positions of the respective ejection port arrays 4C, 4M, 4Y, 4M, 4C, 5B.
1M2, 41C2 and 41B2 are formed. The two cyan and magenta supply ports 41C2 and 41M2 are arranged symmetrically with respect to the yellow supply port 41Y2.

FIG. 11 is a perspective view after the components shown in FIG. 10 have been assembled. As shown in this figure, the assembled ink supply unit has a joint (not shown) that joins the supply ports of the ink tanks for yellow (Y), magenta (M), cyan (C), and black (Bk). Supply port 41Y corresponding to
The ink supplied from the ink supply unit 41c1, 41C1, 41B1 is supplied to the ink supply unit 41c via the ink supply path (dotted line in FIG. 11) formed by the ink supply path forming assemblies 42c1 and 42c2. Supply ports 41C2, 41M2, 41Y2, 41M2, 4 on 41
1C2, 41B2 to 6 ejection port arrays 4 of the recording head unit
C, 4M, 4Y, 4M, 4C, and 4B.

At this time, the number of ink supply paths from the supply port 41Y1 corresponding to the joint portion of the yellow tank to the yellow discharge port array 4Y is the same for black as well. The ink supply path from the supply port 41C1 corresponding to the joint portion of the cyan tank to the same two cyan ejection port arrays 4C is similar to that of magenta, but is bifurcated in the middle.

More specifically, the ink supply path is formed on two planes sandwiched between the ink supply path forming assembly 42c1, the ink supply section 41c, and the ink supply path forming assembly 42c1. An ink supply path that branches into two or more (two in this example) same-type ink ejection port arrays branches in a line symmetric manner (in this example, line symmetry centering on the yellow ejection port array 4Y) on the above plane. Then, the flow path length after the branch is equal in each discharge port array (see FIG. 10C). Thus, the resistance component of the pressure generated by the ink flow from the ink tank to the respective ejection port arrays at the time of supplying the ink can be made almost the same between the ejection port arrays of the same color. As a result, the ink ejection characteristics and the removability of bubbles in the supply path can be made uniform between the ejection port arrays of the same color.

Further, in the present embodiment, since the ink supply paths from the tank joint to the supply ports of each discharge port array are formed on a plurality of planes, the degree of freedom in the layout of the ink supply paths is high. Configuration.

Further, in this configuration, each of the discharge port arrays 4C, 4C
Ink supply ports 41C2, 41M2, 41Y2, 41M2, 4 to be joined to supply ports of M, 4Y, 4M, 4C, 5B
Since 1C2 and 41B2 are provided in the ink supply unit 41c, the height of the supply port is determined only by the component size of the ink supply unit 41c as compared with the third embodiment. Variations in the compression dimension of the seal member can be suppressed.

(Other Embodiments) Lastly, a liquid discharge recording apparatus on which the above-described cartridge type recording head can be mounted will be described. FIG. 12 is an explanatory diagram showing an example of a recording apparatus on which the liquid discharge recording head of the present invention can be mounted.

In the recording apparatus shown in FIG. 12, the head cartridge 1 shown in FIG. 1 is mounted on the carriage 102 so as to be exchangeable while being positioned. The carriage 102 is connected to the carriage 102 via the electrical connection section 6 on the cartridge 1. An electric connection portion for transmitting a drive signal or the like is provided to each ejection port array.

The carriage 102 is guided and supported so as to be able to reciprocate along a guide shaft 103 installed in the apparatus main body and extending in the main scanning direction. The carriage 102 is moved by the main scanning motor 104 to the motor pulley 10.
5. Driven via driving mechanisms such as the driven pulley 106 and the timing belt 107, and the position and movement thereof are controlled. Also, the home position sensor 130
Is provided on the carriage 102. Thus, when the home position sensor 130 on the carriage 102 passes through the position of the shielding plate 136, the position can be known.

The recording medium 108 such as printing paper or plastic thin plate is separated and fed one by one from an auto sheet feeder (hereinafter ASF) 132 by rotating a pickup roller 131 from a paper feeding motor 135 via a gear. Further, by the rotation of the conveying roller 109, the sheet is conveyed (sub-scanning) through a position (printing portion) facing the ejection port surface of the head cartridge 1. The transport roller 109 is driven by a rotation of the LF motor 134 via a gear. At this time, the determination as to whether or not the paper has been fed and the determination of the cueing position at the time of paper feeding are performed when the recording medium 108 passes the paper end sensor 133. Further, the paper end sensor 133 is used to determine where the rear end of the recording medium 108 is actually located and finally determine the current recording position from the actual rear end.
Is used.

The recording medium 108 has its back surface supported by a platen (not shown) so as to form a flat printing surface in the printing section. In this case, the head cartridge 1 mounted on the carriage 102
The ejection port surfaces protrude downward from the carriage 102 and are held between the two pairs of conveyance rollers so as to be parallel to the recording medium 108.

The head cartridge 1 is mounted on the carriage 1 such that the arrangement direction of the ejection ports in each ejection port array is in a direction intersecting the scanning direction of the carriage 102.
The recording is performed by discharging liquid from these discharge port arrays. In the above-described embodiment, in order to eject ink using thermal energy, an electrothermal converter that generates thermal energy is provided. Of course, the present invention provides, for example, ejecting ink using a piezoelectric element. Other ejection methods may be applied.

[0093]

As described above, the liquid discharge recording head according to the present invention includes a recording element having a plurality of discharge port arrays for receiving a liquid supply from a tank for each type of liquid. There are supply paths branched in the middle in accordance with the number of discharge port arrays, and the liquid supply characteristics of these supply paths are substantially equal to those of the same type of liquid.

According to such a configuration, one tank is mounted for each type of liquid, so that the number of parts is reduced, the size of the carriage can be reduced, and the tank can be replaced when the liquid is consumed. Since the operation of the conventional recording head is the same as that of a recording head that is not symmetrically arranged, an operation that is easy for the user to understand is possible.

Further, a resistance component of pressure (pressure loss: determined by a supply path length, a supply path cross-sectional area, a maximum flow velocity, an ink viscosity, and the like) generated by a liquid flow from a tank to each discharge port array at the time of liquid supply. Almost the same can be achieved between discharge port arrays of the same type of liquid. As a result, the liquid ejection characteristics for recording and the removability of bubbles in the supply path can be made uniform between the ejection ports of the same type of liquid.

[Brief description of the drawings]

FIG. 1 is an assembled perspective view showing a recording head cartridge as an example of a liquid discharge recording head of the present invention.

FIG. 2 is an explanatory diagram schematically illustrating a main part of a color recording element of a recording head unit of the recording unit illustrated in FIG. 1;

FIG. 3 is an exploded perspective view for explaining an ink supply path forming assembly provided in the ink supply unit of the head cartridge shown in FIG.

FIG. 4 is a component diagram showing a positional relationship among an ink supply unit, an ink supply path forming assembly, and a recording head unit shown in FIG. 3;

FIG. 5 is a perspective view after the components shown in FIG. 4 are assembled.

FIGS. 6A to 6C are component diagrams showing a positional relationship between an ink supply unit, an ink supply path forming assembly, and a recording head unit shown in FIG. 3, and FIG. It is a perspective view after each component assembling shown in figure (a)-(c).

FIG. 7 is an exploded perspective view for explaining an ink supply path forming assembly provided in the ink supply unit of the head cartridge shown in FIG. 1;

FIG. 8 is a component diagram showing a positional relationship between an ink supply unit, an ink supply path forming assembly, and a recording head shown in FIG. 7;

FIG. 9 is a perspective view after the components shown in FIG. 8 are assembled.

FIG. 10 is a component diagram showing a positional relationship among an ink supply unit, an ink supply path forming assembly, and a recording head unit which constitute the head cartridge shown in FIG.

11 is a perspective view after assembling the components shown in FIG. 9;

FIG. 12 is an explanatory diagram showing an example of a recording apparatus on which the liquid discharge recording head of the present invention can be mounted.

FIG. 13 is a view showing a supporting substrate of the color printing element and the black printing element in FIG. 4A, which are removed.

FIG. 14 is a perspective view showing an ink passage from one ejection port array to an ink supply passage in FIG. 4;

FIG. 15 is an enlarged perspective view of the vicinity of the color discharge unit in FIG. 4 as viewed from the support substrate side.

16 is an enlarged perspective view of the vicinity of the color discharge unit in FIG. 4 as viewed from the discharge port side.

FIG. 17 is an enlarged perspective view showing a modification of FIG. 16;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Recording head cartridge 2 Recording unit 3 Ink supply unit 4 Color recording element 4C Cyan discharge port array 4M Magenta discharge port row 4Y Yellow discharge port row 5 Black recording element 5B Black discharge port row 6 Electric connection part 7 Flexible wiring board 8 Holder unit 9 Ink tank 10, 10a Liquid flow path 11 Discharge port 12, 12a Ink supply port 13 Drive circuit 15 Energy conversion element (heating resistance element) 16 Orifice plate 17 Substrate 18 Wiring 19 Contact pad 20 First discharge port row group 21, 22, 23, 31, 32, 33 Discharge port row 30 Second discharge port row group 40 Joint seal members 41, 41a, 41b Ink supply units 41C, 42C, 42C1, 42C2 Cyan supply ports 41M, 42M, 42M1, 42M2 Magenta supply port 41 Y, 42Y, 42Y1, 42Y2 Yellow supply port 41B, 42B, 42B1, 42B2 Black supply port 42, 42a, 42b1, 42b2 Ink supply path forming assembly 43 Screw 44 Screw boss

Claims (11)

[Claims] A plurality of ejection port arrays for individually ejecting a plurality of types of liquids; and a plurality of ejection port rows provided on a carriage to supply ink to the ejection port arrays. An ink tank, and a liquid supply path for supplying the liquid in the ink tank to the discharge port array, wherein the ink tank has a liquid outlet port communicating with the liquid supply path for each liquid. Wherein the plurality of ejection port arrays are liquid ejection recording heads provided for at least one liquid outlet, and the liquid supply to the plurality of ejection port arrays provided for at least one liquid outlet is provided. A liquid discharge recording head, wherein a path has equivalent liquid supply characteristics between a plurality of discharge port arrays. 2. A plurality of ejection port arrays for individually ejecting a plurality of types of liquids, respectively, and a plurality of ejection port arrays provided on a carriage to supply ink to the ejection port arrays. An ink tank, and a liquid supply path for supplying the liquid in the ink tank to the discharge port array, wherein the ink tank has a liquid outlet port communicating with the liquid supply path for each liquid. Wherein the plurality of ejection port arrays are liquid ejection recording heads provided for at least one liquid outlet, and the liquid supply to the plurality of ejection port arrays provided for at least one liquid outlet is provided. A liquid discharge recording head, wherein a path has equivalent liquid supply characteristics between a plurality of discharge port arrays, and equivalent liquid supply characteristics between discharge port arrays of each type of liquid. 3. The liquid supply path having the equivalent liquid supply characteristic includes one common supply path communicating with the outlet and individual supply paths branched into a number corresponding to the number of discharge port arrays. 2. The liquid discharge recording head according to 1. 4. A supply path connecting part, which is a connecting part of the liquid supply path to the discharge port array, includes two first and second supply paths connected from a first branch of the first supply path. Connecting part and two third and fourth parts connected from the second branch of the second supply path;
A supply path connection part, and a fifth supply path connection part connected to the supply path without branching, wherein each supply path connection part is connected to the first and second branch parts and a fifth supply path connection part. 4. A line symmetrical with respect to a line connecting the portions.
3. The liquid discharge recording head according to item 1. 5. The liquid supply path having the equivalent liquid supply characteristic comprises one common supply path communicating with the outlet and individual supply paths branched into a number corresponding to the number of discharge port arrays. 3. The liquid discharge recording head according to 2. 6. The supply path connection part, which is a connection part of the liquid supply path with respect to the discharge port array, includes a first supply path of the first supply path.
Two first and second supply path connection parts connected from the branch part, two third and fourth supply path connection parts connected from the second branch part of the second supply path, and a branch from the supply path And a fifth supply path connection portion connected to the first and second branch portions and a fifth supply path connection portion. Claim 5
3. The liquid discharge recording head according to item 1. 7. The carriage is bidirectionally scanned with respect to a recording medium, and ejection port arrays corresponding to one or all kinds of liquids are line-symmetric with respect to a line perpendicular to the carriage scanning direction. The liquid discharge recording head according to claim 1, wherein the liquid discharge recording head is disposed at a position other than the first position. 8. The liquid discharge recording head according to claim 7, wherein the connection position of the liquid supply path to the discharge port array corresponding to one or all types of liquid is line-symmetric. 9. The liquid discharge recording head according to claim 3, wherein a connection position of the liquid supply path to a discharge port array corresponding to one or all types of liquid is line-symmetric. 10. A liquid discharge recording head according to claim 1, wherein a liquid is discharged from a desired discharge portion along with scanning of a carriage to record on a recording medium. Liquid ejection recording device to perform. 11. The liquid discharge recording according to claim 1, wherein the liquid supply path is formed by joining only an ink supply unit having a supply port and one or a plurality of supply path forming assemblies. head.