JP2017144701A - Liquid discharge head, and liquid discharge device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate for liquid discharge in which a liquid can be reliably circulated to each of plural element substrates, a liquid discharge head, and a liquid discharge device.SOLUTION: A liquid discharge head includes: plural element substrates which comprises a discharge port for discharging a liquid and a discharge energy generating element for discharging the liquid from the discharge port; a first common channel to which a first part of each of the plural element substrates is connected; a second common channel to which a second part of each of the plural element substrates is connected; plural first introduction parts which are communicated with the first common channel; and plural second introduction parts which are communicated with the second common channel.SELECTED DRAWING: Figure 8

Description

  The present invention relates to a liquid discharge head and a liquid discharge apparatus for discharging various liquids including ink.

  In an ink jet recording head as a liquid discharge head capable of selectively discharging ink as a liquid from a plurality of discharge ports, moisture in the ink evaporates from the discharge ports that do not discharge ink over a long period of time, The ink may thicken. In such a case, there is a possibility that ink cannot be ejected accurately from the ejection port thereafter.

  Patent Document 1 discloses a configuration in which ink is circulated through an ink chamber (pressure chamber) corresponding to an ejection port when ink is not ejected in order to suppress ink thickening in the ejection port when ink is not ejected. Have been described. Specifically, a plurality of ink chambers corresponding to each of the plurality of ejection ports are connected in parallel between the first common flow path and the second common flow path, and the first common flow path A predetermined pressure difference is generated between the one end and the one end of the second common flow path. With such a configuration, ink is circulated through the first common channel, the ink chamber corresponding to the ejection port when ink is not ejected, and the second common channel.

JP 2008-142910 A

  In Patent Document 1, since the pressure of the ink in the first and second common flow paths attenuates from one end portion toward the other end portion thereof, the pressure of the ink chamber connected to the other end portion is reduced. Is difficult to circulate ink.

  Even if the configuration of Patent Document 1 is adopted when an ink jet recording head is configured by arranging a plurality of element substrates on which ejection openings are formed, the above-described case is assumed in which the ink chamber of Patent Document 1 is replaced with an element substrate. There are similar issues.

  The present invention has been made in view of the above problems. An object of the present invention is to provide a liquid discharge head and a liquid discharge apparatus that can circulate liquid to each of a plurality of element substrates.

  In order to solve the above-described problems, a liquid discharge head according to the present invention includes a plurality of element substrates each including a discharge port that discharges liquid, and a discharge energy generating element that discharges liquid from the discharge port. A first common flow path to which each first portion of the element substrate is connected; a second common flow path to which each second portion of the plurality of element substrates is connected; and the first common flow path. A plurality of first introduction parts communicating with the flow path and a plurality of second introduction parts communicating with the second common flow path are included.

  According to the above configuration, by providing a plurality of liquid introducing portions in each of the first and second common flow paths connected to the plurality of element substrates, a sufficient differential pressure of the liquid can be provided to each element substrate. By acting, the liquid can be reliably circulated through each element substrate.

It is a schematic perspective view which shows the internal structure of a liquid discharge apparatus. FIG. 4 is an explanatory diagram for explaining an example of an ink supply system for a head. (A) And (b) is a schematic diagram which shows an element substrate. It is a schematic perspective view which shows the back surface of an element substrate. It is a schematic sectional drawing which shows an element substrate and a support substrate. It is a schematic diagram which shows the structure of the head in 1st Embodiment. (A)-(c) is a figure for demonstrating a comparative example. (A)-(c) is a figure for demonstrating the structure of 1st Embodiment. It is a graph which shows the relationship between the position of a chip | tip, and the flow rate ratio of an ink. It is a schematic diagram which shows the structure of the head in 2nd Embodiment. It is a graph which compares the flow rate ratio of 2nd Embodiment with the flow rate ratio of 1st Embodiment.

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

(First embodiment)
FIG. 1 is a schematic perspective view showing the internal configuration of the liquid ejection apparatus according to the present embodiment. In the following, a case where an ink jet recording apparatus (hereinafter referred to as “recording apparatus”) 200 is used as the liquid ejection apparatus will be described.

  As shown in FIG. 1, the recording apparatus 200 includes a transport mechanism including rollers 205 and 206 and a transport belt 207 stretched around these rollers. Due to the rotation of the roller 205 driven by a motor (not shown) and the rotation of the roller 206 driven by this rotation, the recording medium 208 placed on the conveyance belt 207 is downstream in the conveyance direction (y direction shown in the figure). It is conveyed to the side.

  The recording apparatus 200 uses recording heads 201 to 204 as liquid ejection heads. Here, a case where a plurality of recording heads are used will be described. An ejection port for ejecting liquid is provided on the surface of each recording head facing the recording medium 208. Here, black ink is ejected from the ejection port of the recording head 201, cyan ink is ejected from the ejection port of the recording head 202, magenta ink is ejected from the ejection port of the recording head 203, and yellow ink is ejected from the ejection port of the recording head 204. The Although details will be described later with reference to FIG. 6 and the like, the recording head in this embodiment is a full-line type in which a plurality of element substrates (hereinafter also referred to as “chips”) provided with a plurality of ejection openings are arranged. Recording head. A plurality of discharge ports are formed so as to form a discharge port array extending in a direction intersecting with the conveyance direction of the recording medium 208. Here, a heating resistor element (heater) is used as an ejection energy generating element that generates energy for ejecting liquid from the ejection port. The recording apparatus 200 includes a supply mechanism (not shown) for supplying ink to the recording head.

  Based on the image data input to the recording apparatus 200, a control unit (not shown) controls the transport mechanism, the supply mechanism, and the heater, so that the recording head discharges the recording medium 208 transported by the transport mechanism. Ink is ejected from the outlet in the direction of the arrow z in the figure. In this way, an image is recorded on the recording medium 208 by applying ink to the recording medium 208.

  In the following, the recording head 201 among the recording heads 201 to 204 will be described, but the other recording heads have the same configuration.

  FIG. 2 is an explanatory diagram for explaining an example of a supply system (liquid supply system) capable of supplying ink to the recording head 201. The recording head 201 can have various configurations. For example, a configuration for mounting the recording head 201 to the recording apparatus, a configuration for connecting the recording head 201 to the ink supply system, or a configuration that can be coupled to an ink tank can be provided. As will be described later with reference to FIG. 6, the recording head 201 is provided with supply ports 20 and 21 (first introduction portion) and discharge ports 22 and 23 (second introduction portion). As shown in FIG. 2, the supply port 20 (first opening) fluidly connected to the outside of the liquid discharge head is connected to the sub tank 104a via the tube pump 103a, and the supply port 21 (second opening). Part) is directly connected to the sub-tank 104a. Further, the discharge port 22 (third opening) is connected to the sub tank 104b via the tube pump 103b, and the discharge port 23 (fourth opening) is directly connected to the sub tank 104b. Ink is stored in the main tank 108. The main tank 108 is connected to the sub tanks 104a and 104b. A pump 105 is disposed between the main tank 108 and the sub tanks 104a and 104b. A valve 102a is provided between the pump 105 and the sub tank 104a, and a valve 102b is provided between the pump 105 and the sub tank 104b.

  Further, water level sensors 106 a and 106 b are respectively attached to the sub tanks 104 a and 104 b, and detection signals from the water level sensors 106 a and 106 b are input to the controller 107. The controller 107 controls the pump 105 and the valves 102a and 102b in accordance with detection signals from the water level sensors 106a and 106b. Accordingly, ink is appropriately supplied from the main tank 108 to the sub tanks 104a and 104b, ink is discharged from the sub tanks 104a and 104b to the main tank 108, and the position of the ink level in the sub tanks 104a and 104b can be adjusted. Therefore, the ink head difference H1 between the recording head 201 and the sub-tank 104a and the ink head difference H2 between the recording head 201 and the sub-tank 104b can be maintained at predetermined sizes. The water head difference H2 is larger than the water head difference H1 (H2> H1).

  When discharging ink, the tube pumps 103a and 103b are set in a released state so that ink can flow into the supply ports 20 and 21 from the sub tank 104a, and ink can flow into and out of the discharge ports 22 and 23 from the sub tank 104b. State. Accordingly, a relatively small negative pressure corresponding to the water head difference H1 acts on the ink in the supply ports 20 and 21, and a comparison corresponding to the water head difference H2 is applied to the ink in the discharge ports 22 and 23. A large negative pressure acts. In a resting state where the recording head 201 does not eject ink, the ink in the recording head 201 is circulated by the pressure difference. That is, the ink in the sub tank 104a is supplied from the supply ports 20 and 21 into the pressure chamber R of the recording head 201, and the ink in the pressure chamber R is discharged into the sub tank 104b through the discharge ports 22 and 23. The controller 107 adjusts the position of the ink level in the sub tanks 104a and 104b so as to keep the water head differences H1 and H2 constant.

  The differential pressure generating unit that generates the differential pressure between the ink in the supply ports 20 and 21 and the discharge ports 22 and 23 is not limited to the configuration using the water head difference as in this example, and the sub tanks 104a and 104b. May be configured to function as a pressure chamber that can be adjusted to different pressures. In short, it is sufficient that a pressure difference can be generated between the supply ports 20 and 21 and the discharge ports 22 and 23 so that ink that does not affect ink discharge circulates through the pressure chamber.

  It should be noted that the surface of the recording head 201 on which the ejection opening is formed is covered with a cap 109 during times other than during the recording operation, thereby preventing ink drying, dust adhesion, and the like.

  3A and 3B are schematic views showing the element substrate 1 provided in the recording head 201 as the liquid discharge head, and FIG. 3A is a plan view showing the discharge port and its periphery. FIG. FIG. 3B is a sectional view showing a section taken along line IIIb-IIIb shown in FIG. 3A and 3B show a state where ink is not ejected from the ejection port and ink is circulating.

  As shown in FIG. 3A, the element substrate 1 of the recording head 201 is provided with a plurality of ejection ports 3, flow channel walls 4, ink supply ports 5, and ink discharge ports 6. A pressure chamber R partitioned by the flow path wall 4 is provided at a position between the ink supply port 5 and the ink discharge port 6. Each pressure chamber R is located between the heater 2 and the discharge port 3 facing each other. In addition, a drive circuit (not shown) for driving the heater 2 is formed on the element substrate 1.

  As shown in FIG. 3B, the element substrate 1 is configured by disposing a discharge port forming member 7 for forming the discharge port 3 on a substrate on which the heater 2 is formed. The discharge port forming member 7 is formed with a plurality of pressure chambers (foaming chambers) R partitioned by the flow path wall 4, and each pressure chamber R is located between the discharge port 3 and the heater 2 facing each other. Located in. In the element substrate 1, an ink supply port 5 connected to one side portion of each pressure chamber R and an ink discharge port 6 connected to the other side portion of each pressure chamber R are formed.

  Based on the image data input to the recording apparatus 200, the heater 2 is selectively driven by control by a control unit (not shown), and ink is ejected from the ejection port 3 corresponding to the driven heater 2. In a state where the heater 2 is not driven, the ink at the ejection port 3 forms a meniscus, and no ink is ejected from the ejection port 3. When the heater 2 is driven, ink is foamed by the generated heat, and the ink is pushed out from the discharge port 3 by the pressure generated by the foaming. In this way, after ink is ejected from the ejection port 3, the ink is supplied from the ink supply port 5 and the ink discharge port 6 to the pressure chamber R and the ejection port 3, and the ink is filled. Then, a meniscus is formed again at the ejection port 3, and the next ink can be ejected. When ink is not discharged from the discharge port 3, that is, when the heater 2 corresponding to the discharge port 3 is not driven, the ink supplied from the ink supply port 5 passes through the pressure chamber R and is discharged from the ink discharge port 6. Then, it circulates in the recording apparatus 200.

  As shown in FIG. 3B, the element substrate 1 is provided with a supply flow path 8 and a discharge flow path 9, and the ink supply port 5 communicates with the supply flow path 8. The outlet 6 communicates with the discharge channel 9.

  FIG. 4 is a schematic perspective view showing the back surface of the element substrate 1. As shown in FIG. 4, a plurality of supply channels 8 and a plurality of discharge channels 9 are formed on the back surface of the element substrate 1. Further, a flow path 18 (first flow path) communicating with the plurality of supply flow paths 8 is communicated with one end of the element substrate 1, and a plurality of discharge flow paths 9 are communicated with the other end. Each channel 19 (second channel) is formed.

  FIG. 5 is a schematic cross-sectional view showing the element substrate 1 and the support substrate 13, and shows a part of the recording head 201. As shown in FIG. 5, the element substrate 1 is supported by a support substrate 13. A common supply channel 11 (first common channel) and a common discharge channel 12 (second common channel) are formed in the support substrate 13. The element is connected to the support substrate 13 so that the flow path 18 of the element substrate 1 and the common supply flow path 11 of the support substrate 13 communicate with the flow path 19 of the element substrate 1 and the common discharge flow path 12 of the support substrate, respectively. A substrate 1 is placed. One part of the element substrate 1 is connected to the common supply flow path 11 through the flow path 18, and the other part is connected to the common discharge flow path 12 through the flow path 19. Here, the recording head 201 includes the element substrate 1 and the support substrate 13. The support substrate 13 supports a plurality of element substrates 1. Note that an intermediate substrate that supports each element substrate 1 may be provided between the support substrate 13 and the element substrate 1, and a plurality of intermediate substrates may be supported by the support substrate 13.

  FIG. 6 is a schematic diagram showing the configuration of the recording head 201 in the present embodiment. As shown in FIG. 6, a plurality of chips (element substrates) of chips C <b> 1 to Cn are arranged in a staggered manner to constitute the recording head 201. These chips are connected to a common supply channel 11 and a common discharge channel 12, respectively. The common supply channel 11 and the common discharge channel 12 extend along the arrangement direction of the discharge ports formed in the chip, and are arranged in parallel.

  A supply port 20 is connected to one end of the common supply flow path 11, and a supply port 21 is connected to the other end. A discharge port 22 is connected to one end of the common discharge channel 12, and a discharge port 23 is connected to the other end. That is, the common supply channel 11 is in fluid communication with the outside through the supply ports 20 and 21, and the common discharge channel 12 is in fluid communication with the outside through the discharge ports 22 and 23. As shown in FIG. 6, in the present embodiment, supply ports are provided at both ends of the common supply channel 11, and discharge ports are provided at both ends of the common discharge channel 12. A connection portion of each chip with the common supply channel 11 is disposed between the supply port 20 and the supply port 21. Similarly, the connection part with the common discharge flow path 12 in each chip is disposed between the discharge port 22 and the discharge port 23.

  Details will be described later with reference to FIGS. 8A to 8C. However, when ink is not ejected from any chip, that is, when ink is circulated, ink is supplied from the supply ports 20 and 21 to the chips C1 to Cn. Then, the ink is discharged from the chips C1 to Cn to the discharge ports 22 and 23. When ink is ejected from at least one of the chips, ink is also supplied from the discharge ports 22 and 23 in accordance with the ink ejection state, that is, the ink ejection amount. Thus, in the present embodiment, supply ports are provided at both ends of the common supply channel 11, and discharge ports are provided at both ends of the common discharge channel 12. The effect of this configuration will be described in comparison with a case where a supply port is provided only at one end of the common supply channel 11 and a discharge port is provided only at the other end of the common discharge channel 12.

  FIGS. 7A to 7C are diagrams for explaining a comparative example, FIG. 7A is a schematic diagram illustrating the configuration of the recording head 201 ′, and FIG. 7B is an equivalent circuit diagram. is there. FIG. 7C is a graph showing the pressure difference between the common supply flow path 11 and the common discharge flow path 12 for each chip position, where the vertical axis indicates the pressure and the horizontal axis indicates the chip position. .

  In this comparative example, a relatively small negative pressure corresponding to the water head difference H1 acts on the common supply channel 11 only from the supply port 20, and the water head from only the discharge port 23 acts on the common discharge channel 12. A relatively large negative pressure corresponding to the difference H2 acts. The pressure difference between the supply port 20 and the discharge port 23 is ΔP.

  In this comparative example, if the chip C2 is a non-ejection chip and the other chips C1, C3,... Cn are ejection chips that eject ink droplets I1, I3,. Ink is supplied from both the flow path 11 and the common discharge flow path 12. In that case, as shown in FIG. 7C, the pressure PA in the common supply flow path 11 drops from the chip C1 toward the chip Cn, and the pressure PB in the common discharge flow path 12 changes from the chip Cn to the chip N1. Descent toward you. As a result, the pressure difference at both ends differs greatly depending on the position of the chip, and for the chip located on the right side in FIG. Almost no longer flows.

  As described above, when the circulation flow rate of the ink in the non-ejection chip is reduced, the effect of the circulation is reduced, and the viscosity of the ink is increased by the evaporation of water in the ink at the ejection port 3 at the nozzle tip. There is a risk that good ejection of ink may be hindered. In addition, when the circulation flow rate of ink in each chip is greatly different and the fluctuation range of the circulation flow rate deviates from a predetermined allowable range, there is a possibility that the image recording quality may be impaired due to defective ink ejection.

  On the other hand, in the present embodiment, the fluctuation range of the ink circulation flow rate in each chip is kept small, and the ink circulation is maintained, and the effect of the circulation is sufficiently ensured.

  8A to 8C are diagrams for explaining the configuration of the present embodiment. FIGS. 8A and 8C show the ink in the recording head 201 due to the pressure difference between the supply ports 20 and 21 and the discharge ports 22 and 23 in a pause state where the recording head 201 does not eject ink. It is explanatory drawing when it circulates. FIG. 8A is an equivalent circuit diagram when ink is circulated, and FIG. 8B is an equivalent circuit diagram when ink is ejected. FIG. 8C is a graph showing the pressure difference between the common supply flow path 11 and the common discharge flow path 12 for each chip position. The vertical axis indicates the pressure, and the horizontal axis indicates the chip position. .

  In FIG. 8A, Rc is a flow resistance between adjacent pressure chambers R, C1, C2, C3,..., Cn are chip numbers assigned to a plurality (n) of chips. Includes a corresponding heater 2, pressure chamber R, and discharge port 3. As described above, a negative pressure corresponding to the water head difference H1 acts on each of the supply ports 20 and 21, and a negative pressure corresponding to the water head difference H2 acts on each of the discharge ports 22 and 23. The pressure PA in the common supply flow path 11 and the pressure PB in the common discharge flow path 12 change as shown in FIG. 8C in the chip arrangement direction, and between the flow paths 18 and 19 of the respective chips. An equivalent pressure difference ΔP occurs between them. As a result, in each chip, ink flows from the common supply channel 11 connected to the supply ports 20 and 21 toward the common discharge channel 12 connected to the discharge ports 22 and 23.

  During the recording operation, since the heaters 2 of the nozzles of a plurality of chips are selectively driven in accordance with recording data obtained by performing various image processing on the image data, a chip (ejection chip) that ejects ink, and an ink Chips that do not discharge (non-discharge chips) are mixed.

  FIG. 8B is an explanatory diagram of the ink flow in a state where ejection chips and non-ejection chips are mixed. Depending on the ink discharge status in the recording head 201, the state becomes different from the time of ink circulation as shown in FIGS. That is, after ink is ejected by the foaming energy of the ink in the pressure chamber R of the ejection chip, the negative pressure generated by the defoaming in the pressure chamber resists not only the ink supply port 5 but also the pressure difference ΔP. Ink is also supplied into the pressure chamber R from the ink discharge port 6. Therefore, the discharge ports 22 and 23, the common discharge channel 12, and the ink discharge port 6 supply the ink in the sub tank 104b into the pressure chamber R, contrary to the time of ink circulation.

  For example, as shown in FIG. 8B, the chip C2 is a non-ejection chip and the other chips C1, C2,... Cn are ejection chips that eject ink droplets I1, I3,. Suppose. In this case, as shown in FIG. 8B, substantially the same amount of ink IA and IB flows through both ends of the non-ejection chip C2, that is, the flow path 18 and the flow path 19 of the non-ejection chip C2. The difference between the amounts IA and IB is a slight amount corresponding to the pressure difference ΔP, and the pressure loss in the common supply flow path 11 and the common discharge flow path 12 due to the flow resistance Rc between the chips is almost equal. Become. Therefore, the pressure difference between both ends of the non-ejection chip C2 is hardly affected even when other chips are ejection chips, and ink flows in the direction of the arrow A in the non-ejection chip C2.

  FIG. 9 shows the amount of ink (circulation amount) flowing in the direction of arrow A when the ink is circulated as shown in FIG. 8 (a) and a mixture of ejection chips and non-ejection chips as shown in FIG. 8 (b). It is a graph which shows ratio (flow rate ratio) with the quantity (circulation amount) of the ink of the arrow A direction which flows into a non-ejection chip | tip. Regarding the former ink circulation amount, the ink circulation amount in the chips C1 and Cn located at both ends of the chip row was set to “1”. In FIG. 9, the vertical axis represents the flow rate ratio, and the horizontal axis represents the tip position.

  In this example, as shown in FIG. 9, even if the position of the non-ejection chip is changed, the difference in the ink circulation amount between the two can be suppressed to about several percent. Further, even when the ink is circulated as shown in FIG. 8A, the distribution of the ink circulation amount in the chip arrangement direction can be suppressed to a difference of about several percent as in FIG. .

  As described above, in the present embodiment, it is possible to suppress the fluctuation range of the ink flow rate for each chip while ensuring the flow rate required for circulating the ink. Thereby, in each chip, it is possible to prevent the ink from remaining without being flowed and the water content of the ink from evaporating to increase the viscosity of the ink. Therefore, in the present embodiment, it is possible to prevent a decrease in ink ejection accuracy and the like.

(Second Embodiment)
In this embodiment, in addition to the structure of 1st Embodiment demonstrated with reference to FIG. 6, the supply flow path 11a, the discharge flow path 12a, the supply port 24, and the discharge port 25 are provided. Since other configurations are the same as those of the first embodiment, the description thereof is omitted.

  FIG. 10 is a schematic diagram showing the configuration of the recording head 201 in the present embodiment. As shown in FIG. 10, a supply flow channel 11a connected to the common supply flow channel 11 at the approximate center in the chip arrangement direction, and a discharge flow channel 12a connected to the common discharge flow channel 12 at the approximate center in the chip arrangement direction. Each is provided. In addition, the supply port 24 is opposite to the end of the supply flow path 11a opposite to the end connected to the common supply flow path 11 and the end connected to the common discharge flow path 12 of the discharge flow path 12a. Discharge ports 25 are respectively provided at the end portions on the side.

  In this configuration, when ink is circulated, ink is supplied from the supply ports 20, 21, and 24, and ink is discharged from the discharge ports 22, 23, and 25. Further, depending on the discharge state at the time of ink discharge, ink is supplied not only from the supply ports 20, 21, 24 but also from the discharge ports 22, 23, 25. As a result, when the number of chips is relatively large, even if the length of the common supply flow path 11 and the common discharge flow path 12 is relatively long in the chip arrangement direction, the chip and the supply port or the discharge port The distance between them is prevented from becoming relatively long, and the difference in the ink flow rate of each chip is suppressed.

  FIG. 11 is a graph showing the ink flow rate ratio in the present embodiment and the ink flow rate ratio in the first embodiment, and is a graph corresponding to the graph shown in FIG. 9 described above. FIG. 11 shows the flow rate ratio distribution when the number of chips is the same. As described above, in the present embodiment, the supply flow channel 11a is connected to the common supply flow channel 11 and the discharge flow channel 12a is connected to the common discharge flow channel 12 at approximately the center in the chip arrangement direction (approximately the center of the chip position). Is connected. As a result, ink is supplied from the supply port 24 to the chip located substantially in the center of the chip arrangement direction, and ink is also supplied from the discharge port 25 depending on the discharge situation. Ink is discharged from the chip located substantially in the center of the chip arrangement direction to the discharge port 25. Therefore, as shown in FIG. 10, the flow rate ratio of the chip located substantially at the center is smaller in the configuration of the second embodiment than in the configuration of the first embodiment. That is, in the chip located at the substantially central portion, the ink flow rate when ink is ejected and the ink flow rate when ink is not ejected are substantially unchanged.

  Thus, in the present embodiment, the difference in flow rate between ejection and non-ejection can be further suppressed as compared with the configuration of the first embodiment.

(Other embodiments)
In the above embodiment, the configuration in which the supply ports 20 and 21 are provided at both ends of the common supply flow path 11 and the discharge ports 22 and 23 are provided at both ends of the common discharge flow path 12 has been described. However, the positions of the supply port and the discharge port in the common supply channel and the common discharge channel are not limited to the examples described above. That is, in any flow path, if a plurality of openings serving as ink entrances are provided at positions shifted in the extending direction of each flow path, the same effect as in the above embodiment can be obtained. The ink supply port 5 and the ink discharge port 6 may correspond to the pressure chamber R on a one-to-one basis.

  In the above embodiment, a configuration has been described in which the ink is circulated in each of the chips having a plurality of ejection openings, and the difference in the ink flow rate between the chips is suppressed. However, even when the chip in this embodiment is replaced with a discharge port, the same effect as the present invention can be obtained.

  In the above embodiment, the case where the heating resistor element is used as the recording element has been described. However, a piezo element may be used as the recording element. Although the case of ejecting different colors of ink from the four recording heads has been described, the number of recording heads that can be used and the type of ink color are not particularly limited.

  The present invention is not limited to the ink jet recording head and the ink jet recording apparatus, and can be widely applied as a liquid discharge head and a liquid discharge apparatus for discharging various liquids. The present invention can be applied not only to a full-line recording apparatus as in the above-described embodiment, but also to various types of recording apparatuses such as a so-called serial scan system.

1 Element substrate 2 Heater (Discharge energy generating element)
3 Discharge port 11 Common supply channel (first common channel)
12 Common discharge channel (second common channel)
20, 21 Supply port (first introduction part)
22, 23 Discharge port (second introduction part)
201 Recording head (liquid ejection head)

Claims (14)

A plurality of element substrates comprising: a discharge port for discharging liquid; and a discharge energy generating element for discharging liquid from the discharge port;
A first common flow path to which a first portion of each of the plurality of element substrates is connected;
A second common flow path to which a second portion of each of the plurality of element substrates is connected;
A plurality of first introduction parts communicating with the first common flow path;
A plurality of second introduction parts communicating with the second common flow path;
A liquid discharge head comprising: The plurality of first introduction portions are provided at a plurality of positions shifted in the extending direction of the first common channel in the first common channel,
2. The liquid according to claim 1, wherein the plurality of second introduction parts are provided at a plurality of positions in the second common channel that are shifted in the extending direction of the second common channel. Discharge head. Each of the first portions of the plurality of element substrates is connected to a position shifted in the extending direction of the first common channel in the first common channel,
2. The second portion of each of the plurality of element substrates is connected to a position shifted in the extending direction of the second common channel in the second common channel. Or the liquid discharge head of 2. At least one of the plurality of first introduction portions is provided at an end portion in the extending direction of the first common flow path,
4. The device according to claim 1, wherein at least one of the plurality of second introduction portions is provided at an end portion in the extending direction of the second common flow path. 5. Liquid discharge head. At least two of the plurality of first introduction portions are provided at both ends in the extending direction of the first common flow path,
5. The device according to claim 1, wherein at least two of the plurality of second introduction portions are provided at both end portions in the extending direction of the second common flow path. Liquid discharge head. The plurality of element substrates are arranged along a first direction;
6. The liquid ejection head according to claim 1, wherein the first common flow path and the second common flow path extend along the first direction. 6. The first portion of each of the plurality of element substrates is connected to the first common channel through a first channel corresponding to each of the plurality of element substrates,
2. The second portion of each of the plurality of element substrates is connected to the second common channel through a second channel corresponding to each of the plurality of element substrates. 7. The liquid discharge head according to any one of items 1 to 6. A liquid ejection head according to claim 1;
Control means for controlling the discharge energy generating element;
Liquid supply means capable of supplying liquid to the plurality of first introduction sections and the plurality of second introduction sections;
Differential pressure generating means for generating a differential pressure between the plurality of first introduction portions and the plurality of second introduction portions;
A liquid ejection apparatus comprising:   The liquid ejection apparatus according to claim 8, wherein the differential pressure generating unit generates the differential pressure by a liquid head difference.   A pressure chamber that communicates with the first and second common flow paths and includes the discharge energy generating element therein, and the liquid in the pressure chamber is connected to the outside via the first and second common flow paths; The liquid ejection device according to claim 8, wherein the liquid ejection device is circulated between the two. First and second element substrates including ejection energy generating elements that generate energy used to eject liquid;
A support substrate for supporting the first and second element substrates;
A liquid ejection head comprising:
The support substrate includes a first common channel connected to a first portion of each of the first and second element substrates, and a second portion of each of the first and second element substrates. A second common flow path to be connected,
The first common flow path includes first and second openings in fluid communication with the outside, and the second common flow path includes third and fourth openings in fluid communication with the outside, The connection portion with the first portion of one common flow path is disposed between the first and second openings, and the connection portion with the second portion of the second common flow path is The liquid discharge head is disposed between the third and fourth openings.   The first common flow path supplies liquid to the first and second element substrates, and the second common flow path discharges liquid from the first and second element substrates. The liquid discharge head according to claim 11.   The liquid ejection head according to claim 11, wherein the first common flow path and the second common flow path are arranged in parallel.   A pressure chamber that communicates with the first and second common flow paths and includes the discharge energy generating element therein, and the liquid in the pressure chamber is connected to the outside via the first and second common flow paths; The liquid discharge head according to claim 11, wherein the liquid discharge head is circulated between the liquid discharge heads.