Flexible board, liquid jet head, and liquid jet recording apparatus

Abstract

To provide a flexible substrate etc. which enables improvement of reliability.SOLUTION: A flexible board according to an embodiment of the present disclosure is a flexible board configured to output a drive signal to be applied to a liquid jet head having a plurality of nozzles. The flexible board includes: one or multiple drive devices which are disposed on a board surface to generate the drive signal configured to jet a liquid from the nozzles; a terminal section formed as a portion which is disposed in an end-portion region of the board surface and inserted into a connector on another board; a reinforcing plate which is disposed including the terminal section at a first end portion side on the board surface and configured to adjust a thickness of the board surface; and a stress relaxation part which is disposed in a vicinity of a second end portion at an opposite side of the first end portion in the reinforcing plate and configured to relax stress generated when the flexible board bends.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present disclosure relates to a flexible substrate, an inkjet head, and an inkjet recording apparatus.

Background Art

[0002] Inkjet recording apparatuses equipped with inkjet heads are used in various fields, and various types of inkjet heads have been developed (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In general, such an inkjet head is required to improve reliability. It is desirable to provide a flexible substrate, an inkjet head, and an inkjet recording apparatus capable of improving reliability.

Means for Solving the Problems

[0005] A flexible substrate according to an embodiment of the present disclosure is a flexible substrate that outputs a drive signal applied to an inkjet head having a plurality of nozzles, and includes one or more drive devices that are disposed on a substrate surface and generate a drive signal for ejecting liquid from the nozzles, a terminal portion that is disposed in an end region of the substrate surface and is a portion to be inserted into a connector on another substrate, a reinforcing plate that is disposed on the substrate surface including the terminal portion on a first end side and adjusts the thickness of the substrate surface, and a stress relaxation portion that is disposed near a second end opposite to the first end of the reinforcing plate and relaxes stress generated when the flexible substrate is bent.

[0006] A liquid ejection head according to an embodiment of the present disclosure includes a flexible substrate according to an embodiment of the present disclosure and an ejection unit having a plurality of nozzles that eject liquid based on a drive signal output from the flexible substrate.

[0007] A liquid ejection recording apparatus according to an embodiment of the present disclosure includes the liquid ejection head according to an embodiment of the present disclosure.

Advantages of the Invention

[0008] According to a flexible substrate, a liquid ejection head, and a liquid ejection recording apparatus according to an embodiment of the present disclosure, it is possible to improve reliability.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Mode for Carrying Out the Invention

[0010] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The description will be made in the following order. 1. Embodiment (example of a flexible substrate provided with stress relaxation portions of various configurations) 2. Modification

[0011] <1. Embodiment> [Schematic Configuration of Printer 5] FIG. 1 is a block diagram showing a schematic configuration example of a printer 5 as a liquid ejection recording apparatus according to an embodiment of the present disclosure. FIG. 2 is a schematic perspective view showing a schematic configuration example of an inkjet head 1 as the liquid ejection head shown in FIG. 1. FIG. 3 is a schematic cross-sectional view (Y-Z cross-sectional view) showing a configuration example of the inkjet head 1 shown in FIG. 2. In each drawing used in the description of this specification, the scale of each member is appropriately changed in order to make each member recognizable in size.

[0012] The printer 5 is an inkjet printer that performs recording (printing) of an image, characters, etc. on a recording medium (for example, the recording paper P shown in FIG. 1) using ink 9 described later. As shown in FIG. 1, this printer 5 includes an inkjet head 1, a print control unit 2, and an ink tank 3.

[0013] Note that the inkjet head 1 corresponds to a specific example of the "liquid ejection head" in the present disclosure, and the printer 5 corresponds to a specific example of the "liquid ejection recording apparatus" in the present disclosure. Further, the ink 9 corresponds to a specific example of the "liquid" in the present disclosure.

[0014] (A. Print Control Unit 2) The printing control unit 2 supplies various types of information (data) to the inkjet head 1. Specifically, as shown in FIG. 1, the printing control unit 2 supplies a printing control signal Sc to the inside of the inkjet head 1 (such as a drive device 41 described later). The printing control signal Sc includes, for example, image data, ejection timing signals, and a power supply voltage for operating the inkjet head 1.

[0015] (B. Ink Tank 3) The ink tank 3 is a tank that houses the ink 9 inside. The ink 9 in the ink tank 3 is supplied to the inside of the inkjet head 1 (the ejection unit 11 described later) via the ink supply pipe 30 as shown in FIG. 1. Such an ink supply pipe 30 is composed of, for example, a flexible hose having flexibility.

[0016] (C. Inkjet Head 1) As shown by the dashed arrows in FIG. 1, the inkjet head 1 is a head that ejects (discharges) droplet-like ink 9 onto the recording paper P from a plurality of nozzle holes Hn described later to perform recording of images, characters, etc. The inkjet head 1 includes, for example, as shown in FIGS. 2 and 3, one ejection unit 11, one I / F (interface) board 12, four flexible boards 13a, 13b, 13c, 13d, and two cooling units 141, 142.

[0017] (C-1. I / F Board 12) As shown in FIGS. 2 and 3, the I / F board 12 includes two connectors 10, four connectors 120a, 120b, 120c, 120d, and a circuit arrangement area 121.

[0018] As shown in FIG. 2, the connector 10 is a portion (connector portion) that inputs the above-described printing control signal Sc supplied from the printing control unit 2 toward the inkjet head 1 (flexible substrates 13a, 13b, 13c, 13d described later). The connectors 120a, 120b, 120c, and 120d are each a portion (connector portion) that electrically connects between the I / F substrate 12 and the flexible substrates 13a, 13b, 13c, and 13d, respectively.

[0019] The circuit arrangement area 121 is an area on the I / F substrate 12 where various circuits are arranged. Note that such a circuit arrangement area may be provided in other areas on the I / F substrate 12 as well.

[0020] (C-2. Injection unit 11) As shown in FIG. 1, the injection unit 11 has a plurality of nozzle holes Hn, and is a portion that injects the ink 9 from these nozzle holes Hn. Such injection of the ink 9 is performed according to a drive signal Sd (drive voltage Vd) supplied from a drive device 41 described later on each of the flexible substrates 13a, 13b, 13c, and 13d (see FIG. 1).

[0021] As shown in FIG. 1, such an injection unit 11 includes an actuator plate 111 and a nozzle plate 112.

[0022] (Nozzle plate 112) The nozzle plate 112 is a plate made of a film material such as polyimide or a metal material, and has the above-described plurality of nozzle holes Hn as shown in FIG. 1. These nozzle holes Hn are formed side by side at a predetermined interval and are, for example, circular in shape. Note that each of these nozzle holes Hn corresponds to a specific example of the "nozzle" in the present disclosure.

[0023] In the example of the injection unit 11 shown in FIG. 2, a plurality of nozzle holes Hn in the nozzle plate 112 are constituted by a plurality of nozzle rows (four nozzle rows) respectively arranged along the column direction (X-axis direction). Further, these four nozzle rows are arranged side by side along the direction orthogonal to the column direction (Y-axis direction).

[0024] (Actuator plate 111) The actuator plate 111 is a plate made of a piezoelectric material such as PZT (lead zirconate titanate). A plurality of channels (pressure chambers) are provided in the actuator plate 111. These channels are parts for applying pressure to the ink 9 and are arranged side by side at a predetermined interval so as to be parallel to each other. Each channel is defined by a drive wall (not shown) made of a piezoelectric body and has a groove portion that is concave in cross-section view.

[0025] In such channels, there are a discharge channel for discharging the ink 9 and a dummy channel (non-discharge channel) for not discharging the ink 9. In other words, while the discharge channel is filled with the ink 9, the dummy channel is not filled with the ink 9. Note that the filling of the ink 9 into each discharge channel is performed, for example, via a flow path (common flow path) that communicates in common with such each discharge channel. Further, each discharge channel communicates individually with the nozzle hole Hn in the nozzle plate 112, while each dummy channel does not communicate with the nozzle hole Hn. These discharge channels and dummy channels are arranged alternately along the column direction (X-axis direction) described above.

[0026] In addition, drive electrodes are provided on the opposing inner surfaces of the drive walls described above. On this drive electrode, there exist a common electrode provided on the inner surface facing the discharge channel and an active electrode (individual electrode) provided on the inner surface facing the dummy channel. Between these drive electrodes and a drive device 41 described later, they are electrically connected via flexible substrates 13a, 13b, 13c, 13d. As a result, via the flexible substrates 13a, 13b, 13c, 13d, the drive voltage Vd (drive signal Sd) described above is applied from the drive device 41 to each drive electrode (see FIG. 1).

[0027] (C-3. Flexible Substrates 13a, 13b, 13c, 13d) The flexible substrates 13a, 13b, 13c, 13d are each a substrate that electrically connects between the I / F substrate 12 and the ejection unit 11 as shown in FIGS. 2 and 3. Each of these flexible substrates 13a, 13b, 13c, 13d is configured to individually control the ejection operation of the ink 9 for each of the four nozzle rows in the nozzle plate 112 described above. Also, for example, as indicated by the reference numerals P1a, P1b, P1c, P1d in FIG. 3, near the location where each flexible substrate 13a, 13b, 13c, 13d is connected to the ejection unit 11 (near the pressure-bonding electrode portion 433), each flexible substrate 13a, 13b, 13c, 13d is configured to be bent. Note that between the pressure-bonding electrode portion 433 and the ejection unit 11, electrical connection is made to each other, for example, by thermocompression bonding using an ACF (Anisotropic Conductive Film). Also, for example, another flexible substrate having only wiring may be further ACF pressure-bonded to the flexible substrates 13a, 13b, 13c, 13d, and this another flexible substrate and the ejection unit 11 may be ACF pressure-bonded.

[0028] On such flexible substrates 13a, 13b, 13c, 13d (on the wiring layer on the surface S1 side to be described later), one or more driving devices 41 are individually mounted (see FIG. 3). Each of these driving devices 41 is a device that outputs a driving signal Sd (driving voltage Vd) for ejecting the ink 9 from the nozzle holes Hn in the corresponding nozzle row in the ejection unit 11. Therefore, such a driving signal Sd is output from each of the flexible substrates 13a, 13b, 13c, 13d to the ejection unit 11. Note that each of such driving devices 41 is constituted by, for example, an ASIC (Application Specific Integrated Circuit) or the like.

[0029] In addition, each of these driving devices 41 is cooled by the cooling units 141, 142 described above. Specifically, as shown in FIG. 3, the cooling unit 141 is fixedly arranged between the driving devices 41 on the flexible substrates 13a, 13b, and each of these driving devices 41 is cooled by the cooling unit 141 being pressed against them. Similarly, the cooling unit 142 is fixedly arranged between the driving devices 41 on the flexible substrates 13c, 13d, and each of these driving devices 41 is cooled by the cooling unit 142 being pressed against them. Note that each of such cooling units 141, 142 can be configured using various cooling mechanisms.

[0030] [Detailed Configuration of Flexible Substrates 13a, 13b, 13c, 13d] Subsequently, with reference to FIGS. 4 and 5 in addition to FIGS. 1 to 3, a detailed configuration example of the above-described flexible substrates 13a, 13b, 13c, 13d will be described.

[0031] FIG. 4 schematically shows a plan view (Z-X plan view) of a schematic configuration example of the flexible substrates 13a to 13d (hereinafter collectively referred to as the flexible substrate 13 as appropriate) shown in FIGS. 2 and 3. FIG. 5 schematically shows a cross-sectional view (Y-Z cross-sectional view) of the schematic configuration example of the flexible substrate 13 shown in FIG. 4.

[0032] First, this flexible substrate 13 is a double-sided substrate having a multi-layer structure including a front surface S1 and a back surface S2. Specifically, this flexible substrate 13 has, as wiring layers of such a multi-layer structure (two-layer structure), a first wiring layer on the front surface S1 side and a second wiring layer on the back surface S2 side that face each other along the direction (Y-axis direction) orthogonal to the substrate surface (Z-X plane).

[0033] Note that the wiring layer in the flexible substrate 13 may have a structure of three or more layers including, for example, the above-described first wiring layer and second wiring layer.

[0034] Also, as shown in FIGS. 4 and 5, this flexible substrate 13 has the above-described one or more drive devices 41 (three drive devices 41 in this example), a wiring pattern 42, a terminal portion 130, a reinforcing plate 131, and a stress relaxation portion 132.

[0035] The drive device 41 is arranged on the substrate of the flexible substrate 13 (on the first wiring layer on the front surface S1 side) as described above. Also, in the example of FIG. 4, a plurality of drive devices 41 (three drive devices 41 in this example) are arranged side by side along the X-axis direction on the substrate of the flexible substrate 13.

[0036] The wiring pattern 42 is a pattern of various wirings electrically connected to the drive device 41 as shown in FIG. 4. In the example of FIG. 4, the wiring pattern 42 includes a signal wiring pattern 42s corresponding to the wiring of various signals, a power supply wiring pattern 42d corresponding to the wiring of various power supplies, and a ground wiring pattern 42g corresponding to the ground wiring.

[0037] The terminal portion 130 is disposed in an end region on the I / F substrate 12 side on the surface S1 of the flexible substrate 13 (see FIG. 4), and includes a plurality of terminals (terminals T described later) for electrically connecting between the flexible substrate 13 and the I / F substrate 12. In other words, this terminal portion 130 is a portion to be inserted into the connectors 120a to 120d on the I / F substrate 12 as another substrate.

[0038] The reinforcing plate 131 is disposed on the substrate of the flexible substrate 13 (on the first wiring on the surface S1 side) and includes the terminal portion 130 on the first end portion e1 side (see FIGS. 4 and 5), and is a member for adjusting the thickness of the substrate surface of the flexible substrate 13.

[0039] The stress relaxation portion 132 is disposed near the second end portion e2 on the side opposite to the first end portion e1 of the reinforcing plate 131 (on the arrangement region side of the drive device 41) (see FIGS. 4 and 5). Although details will be described later, it is configured to relax the stress generated when the flexible substrate 13 is bent.

[0040] [Embodiments Regarding the Configuration of the Stress Relaxation Portion 132] Here, with reference to FIGS. 6 to 12 in addition to FIGS. 1 to 5, embodiments (Embodiments 1 to 5) regarding the configuration of such a stress relaxation portion 132 will be described in detail while comparing with the configurations of comparative examples (Comparative Examples 1 and 2).

[0041] FIGS. 6 and 9 respectively schematically show configuration examples of flexible substrates (flexible substrates 103 and 203) according to Comparative Examples 1 and 2 in a plan view (Z-X plan view). FIGS. 7, 8, 10, 11, and 12 respectively schematically show configuration examples of flexible substrates (flexible substrates 13A to 13E) according to Embodiments 1 to 5 in a plan view (Z-X plan view). In FIG. 12, an enlarged configuration of the portion indicated by the reference sign P1 is separately shown within the region indicated by the broken line.

[0042] (Comparative Example 1) First, in the flexible substrate 103 of Comparative Example 1 shown in FIG. 6, unlike the flexible substrate 13A of Example 1 described below, the power supply wiring pattern 42d and the ground wiring pattern 42g are arranged inside (on the driving device 41 side) of the second end portion e2 of the reinforcing plate 131. That is, in this flexible substrate 103, the power supply wiring pattern 42d and the ground wiring pattern 42g are not arranged so as to straddle the second end portion e2 of the reinforcing plate 131 on the substrate surface. For this reason, although details will be described later, the risk of cracks occurring due to the bending of the flexible substrate 103 is high in the vicinity of the second end portion e2 of the reinforcing plate 131.

[0043] (Examples 1 to 4) On the other hand, all of the flexible substrates 13A to 13D of Examples 1 to 4 shown in FIGS. 7, 8, 10, and 11 are configured as follows. That is, in all of these flexible substrates 13A to 13D, the reinforcing pattern that functions as the stress relaxation portion 132 (132A to 132D) is arranged on the substrate surface so as to straddle the second end portion e2 of the reinforcing plate 131.

[0044] Specifically, in the flexible substrate 13A of Example 1 shown in FIG. 7, the reinforcing pattern that functions as the stress relaxation portion 132A is configured using the power supply wiring pattern 42d or the ground wiring pattern 42g. That is, these power supply wiring pattern 42d or ground wiring pattern 42g are arranged on the substrate surface of the flexible substrate 13A so as to straddle the second end portion e2 of the reinforcing plate 131.

[0045] Further, in the flexible substrate 13B of Example 2 shown in FIG. 8, the reinforcing pattern that functions as the stress relaxation portion 132B is configured using a dedicated pattern 43 that is different from the wiring pattern 42 electrically connected to the drive device 41. That is, this dedicated pattern 43 is arranged on the substrate surface of the flexible substrate 13B so as to straddle the second end portion e2 of the reinforcing plate 131. In this case, the dedicated pattern 43 is arranged, for example, on a wiring layer different from the wiring pattern 42. Alternatively, for example, the wiring layer may be sparse and the dedicated pattern 43 may be inserted between the signal lines. In this way, the dedicated pattern 43 is a pattern electrically separated from the wiring pattern 42 (signal wiring pattern 42s, power supply wiring pattern 42d, and ground wiring pattern 42g).

[0046] On the other hand, the flexible substrates 13C and 13D of Examples 3 and 4 shown in FIGS. 10 and 11 respectively have the following configurations. That is, in these flexible substrates 13C and 13D, in the signal wiring pattern 42s electrically connected to the drive device 41, a wide portion W with a relatively wide wiring width is provided, and the reinforcing pattern that functions as the stress relaxation portions 132C and 132D is configured using the wide portion W in the signal wiring pattern 42s. That is, such a wide portion W in the signal wiring pattern 42s is arranged on the substrate surface of the flexible substrates 13C and 13D so as to straddle the second end portion e2 of the reinforcing plate 131. In the examples of FIGS. 10 and 11, the signal wiring pattern 42s is arranged on the second wiring layer on the back surface S2 side of the flexible substrates 13C and 13D, and each signal wiring is individually electrically connected to each terminal T in the terminal portion 130. Also, for example, After the power supply wiring pattern 42d and the ground wiring pattern 42g are arranged on this second wiring layer, a pattern relatively wider than the signal wiring pattern 42s (with the wide portion W provided) may be formed to form the reinforcing pattern.

[0047] (Comparative Example 2) In contrast, in the flexible substrate 203 of Comparative Example 2 shown in FIG. 9, the wide portion W that functions as the above-described reinforcing pattern is not provided in the signal wiring pattern 42s. Therefore, although details will be described later, similar to the case of Comparative Example 1 described above, the risk of cracks occurring due to the bending of the flexible substrate 203 is high in the vicinity of the second end portion e2 of the reinforcing plate 131.

[0048] (Example 5) Further, in the flexible substrate 13E of Example 5 shown in FIG. 12, the shape of the second end portion e2 in the reinforcing plate 131 is configured by a non-linear shape that functions as a stress relaxation portion 132E, which is different from the flexible substrates 13A to 13D described so far. Also, in the example of FIG. 12, such a non-linear shape is a wave shape. Note that such a non-linear shape may be other shapes such as a triangular shape or a concavo-convex shape.

[0049] Note that the above-described power supply wiring pattern 42d, ground wiring pattern 42g, dedicated pattern 43, and wide portion W respectively correspond to a specific example of the "reinforcing pattern" in the present disclosure.

[0050] [Operation, Action, and Effect] (A. Basic Operation of Printer 5) In this printer 5, a recording operation (printing operation) of an image, characters, etc. on a recording medium (recording paper P, etc.) is performed using an ink ejection operation of ink 9 by the following inkjet head 1. Specifically, in the inkjet head 1 of the present embodiment, an ink ejection operation of ink 9 using a shear mode is performed as follows.

[0051] First, each drive device 41 on each flexible substrate 13 (13a, 13b, 13c, 13d) applies a drive voltage Vd (drive signal Sd) to the aforementioned drive electrodes (common electrode and active electrode) in the actuator plate 111 in the ejection unit 11. Specifically, each drive device 41 applies the drive voltage Vd to each drive electrode arranged on a pair of drive walls that define the aforementioned discharge channel. As a result, each of these pair of drive walls deforms so as to protrude toward the dummy channel side adjacent to its discharge channel.

[0052] At this time, with the intermediate position in the depth direction of the drive wall as the center, the drive wall will bend and deform in a V shape. And due to such bending deformation of the drive wall, the discharge channel deforms as if it swells. In this way, due to the bending deformation caused by the piezoelectric thickness slip effect in the pair of drive walls, the volume of the discharge channel increases. And when the volume of the discharge channel increases, the ink 9 is induced into the discharge channel.

[0053] Next, the ink 9 induced into the discharge channel in this way propagates inside the discharge channel as a pressure wave. And at the timing when this pressure wave reaches the nozzle hole Hn of the nozzle plate 112 (or the timing in the vicinity thereof), the drive voltage Vd applied to the drive electrode becomes 0 (zero) V. As a result, the drive wall returns from the above-described bent deformation state, and the once-increased volume of the discharge channel returns to its original state again.

[0054] In this way, in the process of the volume of the discharge channel returning to its original state, the pressure inside the discharge channel increases, and the ink 9 in the discharge channel is pressurized. As a result, the ink 9 in droplet form is ejected to the outside (toward the recording paper P) through the nozzle hole Hn (see Fig. 1). In this way, the ejection operation (discharge operation) of the ink 9 in the inkjet head 1 is performed, and as a result, the recording operation of an image, characters, etc. on the recording paper P is performed.

[0055] (B. Action and effect in the inkjet head 1) Next, the operation and effects of the inkjet head 1 of the present embodiment will be described in detail.

[0056] (B-1. Conventional Inkjet Head) First, in a drive substrate (flexible substrate) used in a conventional inkjet head, it is common to mount a connector on the other side (connection destination) substrate and insert the terminal portion of the flexible substrate into the connector. Also, when connecting a flexible substrate to a connector, it is common to provide a reinforcing plate at the insertion portion (near the terminal portion) to the connector to match the thickness according to the connector specification.

[0057] Such a flexible substrate has flexibility, is strong against pulling, and can withstand a certain degree of bending. However, when a crack occurs, there is a risk of breaking starting from the crack. Also, in a flexible substrate, in order to absorb assembly errors and provide freedom in substrate arrangement, the pattern may be made sparse to have flexibility, or the pattern may be removed to create a difference in rigidity to provide a bending point. In particular, since the end portion (edge portion) of the above-described reinforcing plate is likely to be used as a bending point, in order to further stabilize the bending point, the pattern at the end of the reinforcing plate may be made sparse to support the bending position.

[0058] However, when a flexible substrate is used in an ink atmosphere, as in the case of an inkjet head, the polyimide may deteriorate due to the ink components, and the flexibility of the flexible substrate may be lost, resulting in a case where it becomes more vulnerable to bending. Although a flexible substrate inherently has flexibility and can withstand multiple bendings, if excessive stress is repeatedly applied to a material that has deteriorated as described above, cracks as described above may occur due to material fatigue.

[0059] In particular, the end portion of the above-described reinforcing plate has a thickness several times that of the polyimide serving as the base material. When bent, the material extends from the end portion as the starting point, increasing the risk of cracks occurring in the deteriorated polyimide. That is, the end portion of the reinforcing plate may serve as the starting point of cracks. When such cracks occur in the flexible substrate, copper is exposed on the cross-section of the substrate. In the ink usage environment as described above, since there is also a risk of the exposed copper corroding, it can be said that cracks (copper exposure) in the flexible substrate are unacceptable.

[0060] In this way, in the flexible substrates (including the flexible substrates 103 and 203 of the above-described Comparative Examples 1 and 2) of the conventional inkjet heads, cracks may occur in the vicinity of the end portion (the second end portion e2) of the reinforcing plate, leading to a possible reduction in reliability.

[0061] (B-2. Action and Effect) On the other hand, in the inkjet head 1 of the present embodiment, since the flexible substrate 13 (13A to 13E) has the following configuration, for example, the following actions and effects can be obtained.

[0062] That is, first, in the flexible substrate 13 of the present embodiment, a stress relaxation portion 132 is provided near the second end portion e2 (the side opposite to the first end portion e1 where the terminal portion 130 is disposed) of the reinforcing plate 131. As a result, the stress generated when the flexible substrate 13 is bent as described above is relaxed. Therefore, even in the environment where the ink 9 is used in the inkjet head 1, the risk of cracks occurring in the flexible substrate 13 near the second end portion e2 of the reinforcing plate 131 is reduced. As a result, in the present embodiment, it is possible to improve the reliability of the flexible substrate 13 as compared with the above-described Comparative Examples 1, 2, etc.

[0063] Also, for example, in the case where various reinforcing patterns (such as the power supply wiring pattern 42d, the ground wiring pattern 42g, the dedicated pattern 43, or the wide portion W described above) as stress relaxation portions 132A to 132D are arranged so as to straddle the second end portion e2 of the reinforcing plate 131, as in the flexible substrates 13A to 13D, the following occurs. That is, since the rigidity in the vicinity of this second end portion e2 is improved and bending is less likely to occur, for example, even when repeated bending or excessive bending occurs, the possibility of cracks occurring in the flexible substrate 13 is reduced. Therefore, as described above, it becomes possible to improve the reliability of the flexible substrates 13A to 13D.

[0064] In particular, for example, in the case where the above-described reinforcing pattern is configured using the wide portion W in the signal wiring pattern 42s, as in the flexible substrates 13C and 13D, the following occurs. That is, even if the flexible substrates 13C and 13D are, for example, single-sided wiring flexible substrates, a reinforcing pattern can be provided, and it becomes possible to realize a simple configuration.

[0065] Also, for example, in the case where the above-described reinforcing pattern is configured using a dedicated pattern 43 different from the wiring pattern 42 that is electrically connected to the drive device 41, as in the flexible substrate 13B, the following occurs. That is, since a dedicated pattern 43 different from such a wiring pattern 42 is used, it becomes possible to improve the degree of freedom in arranging the wiring pattern 42 within the flexible substrate 13B.

[0066] Also, for example, in the case where the second end portion e2 of the reinforcing plate 131 is configured in a non-linear shape (such as a wave shape) that functions as the stress relaxation portion 132E, as in the flexible substrate 13E, the following occurs. That is, the bending portions on the flexible substrate 13E are dispersed vertically, and the load in the vicinity of the second end portion e2 is also dispersed. Therefore, material fatigue in the flexible substrate 13E is suppressed, and the possibility of cracks occurring is reduced. Therefore, as described above, it becomes possible to improve the reliability of the flexible substrate 13E.

[0067] <2. Modification Example> As described above, the present disclosure has been explained by giving some embodiments and examples. However, the present disclosure is not limited to these embodiments and the like, and various modifications are possible.

[0068] For example, in the above embodiments and the like, configuration examples (shape, arrangement, number, etc.) of each member in the printer and the inkjet head have been specifically described. However, it is not limited to those described in the above embodiments and the like, and other shapes, arrangements, numbers, etc. may be used.

[0069] Specifically, for example, in the above embodiments and the like, configuration examples (shape, arrangement, number, etc.) of a flexible substrate, a driving device, and various wiring patterns have been specifically described. However, these configuration examples are not limited to those described in the above embodiments and the like. For example, in the above embodiments and the like, an example in which a plurality of driving substrates are provided in the inkjet head has been described. However, this is not limited to this example. For example, only one driving substrate may be provided in the inkjet head. Further, in the above embodiments and the like, an example in which a plurality of driving devices are provided on the driving substrate has been described. However, this is not limited to this example. For example, only one driving device may be provided on the driving substrate. Furthermore, in the above embodiments and the like, the shape of the driving device is rectangular, but this is not limited to this example. For example, it may be square.

[0070] In addition, as the structure of the inkjet head, each type can be applied. That is, for example, a so-called side shoot type inkjet head that discharges ink 9 from the central portion in the extending direction of each discharge channel in the actuator plate 111 may be used. Alternatively, for example, a so-called edge shoot type inkjet head that discharges ink 9 along the extending direction of each discharge channel may be used. Furthermore, as the printer method, it is not limited to the method described in the above embodiments and the like. For example, various methods such as the MEMS (Micro Electro Mechanical Systems) method can be applied.

[0071] Furthermore, for example, either a circulating type inkjet head that circulates and uses ink 9 between the ink tank and the inkjet head, or a non-circulating type inkjet head that uses ink 9 without circulation can apply the present disclosure.

[0072] Also, the series of processes described in the above embodiments and the like may be performed by hardware (circuit) or by software (program). When performed by software, the software is composed of a group of programs for causing a computer to execute each function. Each program may be, for example, pre-installed in the above computer and used, or may be installed from a network or a recording medium into the above computer and used.

[0073] Furthermore, in the above embodiments and the like, as a specific example of the "liquid jet recording apparatus" in the present disclosure, the printer 5 (inkjet printer) has been described, but this is not limited to this example, and the present disclosure can also be applied to other devices other than inkjet printers. In other words, the "liquid jet head" (inkjet head) of the present disclosure may be applied to other devices other than inkjet printers. Specifically, for example, the "liquid jet head" of the present disclosure may be applied to devices such as facsimiles and on-demand printers.

[0074] In addition, the various examples described so far may be applied in any combination.

[0075] Note that the effects described in this specification are merely illustrative and not limiting, and there may be other effects.

[0076] Also, the present disclosure can take the following configurations. (1) A flexible substrate that outputs a drive signal applied to a liquid ejection head having a plurality of nozzles, One or more drive devices that are disposed on the substrate surface and generate the drive signal for ejecting liquid from the nozzles, A terminal portion that is disposed in an end region of the substrate surface and is a portion to be inserted into a connector on another substrate, A reinforcing plate that is disposed on the substrate surface including the terminal portion on the first end side and adjusts the thickness of the substrate surface, A stress relaxation portion that is disposed near a second end opposite to the first end of the reinforcing plate and relaxes stress generated when the flexible substrate is bent A flexible substrate provided with. (2) The reinforcing pattern as the stress relaxation portion is disposed on the substrate surface so as to straddle the second end of the reinforcing plate The flexible substrate according to (1) above. (3) The reinforcing pattern is configured using a power supply wiring pattern or a ground wiring pattern that is electrically connected to the drive device The flexible substrate according to (2) above. (4) In a signal wiring pattern that is electrically connected to the drive device, a wide portion with a relatively wide wiring width is provided, The reinforcing pattern is configured using the wide portion in the signal wiring pattern The flexible substrate according to (2) above. (5) The reinforcing pattern is configured using a dedicated pattern different from the wiring pattern electrically connected to the drive device. The flexible substrate according to (2) above. (6) The second end portion of the reinforcing plate is configured in a non-linear shape that functions as the stress relaxation portion. The flexible substrate according to (1) above. (7) The non-linear shape is a waveform. The flexible substrate according to (6) above. (8) The flexible substrate according to any one of (1) to (7) above, and an ejection unit having the plurality of nozzles that ejects the liquid based on the drive signal output from the flexible substrate. A liquid ejection head including the same. (9) A liquid ejection recording apparatus including the liquid ejection head according to (8) above. Liquid ejection recording apparatus.

Explanation of Signs

[0077] 1... Inkjet head, 10... Connector, 11... Ejection unit, 111... Actuator plate, 112... Nozzle plate, 12... I / F substrate, 120a, 120b, 120c, 120d... Connectors, 121... Circuit arrangement area, 13, 13a, 13b, 13c, 13d, 13A to 13E... Flexible substrates, 130... Terminal portion, 131... Reinforcing plate, 132, 132A to 132E... Stress relaxation portions, 141, 142... Cooling units, 2... Printing control unit, 3... Ink tank, 30... Ink supply pipe, 41... Drive device, 42... Wiring pattern, 42s... Signal wiring pattern, 42d... Power supply wiring pattern, 42g... Ground wiring pattern, 43... Dedicated pattern, 433... Crimping electrode, 5... Printer, 9... Ink, P... Recording paper, Hn... Nozzle hole, Sc... Printing control signal, Sd... Drive signal, Vd... Drive voltage, S1... Front surface, S2... Back surface, e1... First end portion, e2... Second end portion, W... Wide portion.

Claims

1. A flexible printed circuit board that outputs a drive signal applied to a liquid ejection head having a plurality of nozzles, One or more drive devices disposed on the board surface for generating the drive signal for ejecting liquid from the nozzles, A terminal portion disposed in an end region of the board surface and being a portion to be inserted into a connector on another board, A reinforcing plate disposed on the board surface including the terminal portion on a first end side for adjusting the thickness of the board surface, A stress relaxation portion disposed near a second end opposite to the first end of the reinforcing plate for relaxing stress generated when the flexible printed circuit board is bent A flexible printed circuit board comprising.

2. A reinforcing pattern as the stress relaxation portion is disposed on the board surface so as to straddle the second end of the reinforcing plate The flexible printed circuit board according to claim 1.

3. The reinforcing pattern is configured using a power supply wiring pattern or a ground wiring pattern that is electrically connected to the drive device The flexible printed circuit board according to claim 2.

4. In a signal wiring pattern electrically connected to the drive device, a wide portion with a relatively wide wiring width is provided, The reinforcing pattern is configured using the wide portion in the signal wiring pattern The flexible printed circuit board according to claim 2.

5. The reinforcing pattern is configured using a dedicated pattern different from the wiring pattern electrically connected to the drive device The flexible printed circuit board according to claim 2.

6. The second end of the reinforcing plate is configured in a non-linear shape that functions as the stress relaxation portion The flexible printed circuit board according to claim 1.

7. The non-linear shape is a waveform The flexible printed circuit board according to claim 6.

8. A flexible printed circuit board according to any one of claims 1 to 7, An ejection unit having the plurality of nozzles for ejecting the liquid based on the drive signal output from the flexible printed circuit board A liquid ejection head comprising.

9. Comprising the liquid ejection head according to claim 8 A liquid ejection recording apparatus.

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