Liquid dispensing head

Abstract

This enables the maintenance of the quality of the drive signals output from the drive member to the individual electrodes. [Solution] The head includes a flow channel member having a plurality of pressure chambers, an actuator member having a plurality of individual electrodes that overlap each of the plurality of pressure chambers in the vertical direction and a plurality of contacts connected to each of the plurality of individual electrodes, a wiring member disposed on the upper surface of the actuator member, and a driver IC having a plurality of output terminals that each output a drive signal. The wiring member has a plurality of wires 142, each with a plurality of contacts 149 that are connected to the plurality of contacts. Each of the plurality of output terminals of the driver IC is connected to the other end of the plurality of wires. A plurality of contacts 149 are connected to one of the plurality of contacts of the actuator member.

Description

Technical Field

[0001] The present invention relates to a liquid ejection head that ejects liquid.

Background Art

[0002] Patent Document 1 describes an inkjet head (liquid ejection head) including a flow path unit (flow path member) having a plurality of pressure chambers, a piezoelectric actuator (actuator member) disposed on the upper surface of the flow path unit, and a flexible wiring member (wiring member) including a plurality of wiring patterns. The piezoelectric actuator has a plurality of individual electrodes that overlap with each of the plurality of pressure chambers in the vertical direction, and a plurality of individual surface electrodes disposed on the upper surface and connected to each of the plurality of individual electrodes. A driver IC (driving member) connected to the plurality of wiring patterns is mounted on the flexible wiring member. The plurality of wiring patterns include a plurality of individual bonding electrodes joined to each of the plurality of individual surface electrodes. The inkjet head applies a predetermined voltage to the plurality of individual electrodes based on a driving signal output from the driver IC, and applies pressure to the ink in the plurality of pressure chambers.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the inkjet head described in Patent Document 1 above, the output terminal of the driver IC and the individual bonding electrodes are electrically connected by a single output wiring pattern. Therefore, there is only one transmission path for the drive signal output from the driver IC to each individual electrode. When the piezoelectric actuator is driven at high speed by the driver IC, the loss in the single transmission path to the individual electrodes affects the quality of the drive signal to the individual electrodes, degrading its quality. Furthermore, because the output terminal of the driver IC and the individual bonding electrodes are electrically connected by a single output wiring pattern, the quality of the drive signal to the individual electrodes is also degraded due to breaks in the wiring or changes in output characteristics caused by pressure during head manufacturing.

[0005] Therefore, the object of the present invention is to provide a liquid dispensing head that can maintain the quality of the drive signal output from the drive member to the individual electrodes. [Means for solving the problem]

[0006] The liquid discharge head of the present invention comprises: a flow channel member having a plurality of pressure chambers; an actuator member disposed on the upper surface of the flow channel member, having a plurality of individual electrodes that overlap each of the plurality of pressure chambers in the vertical direction, and a plurality of first contacts disposed on the upper surface and connected to each of the plurality of individual electrodes; a wiring member disposed on the upper surface of the actuator member, having a plurality of wires, each having a plurality of second contacts connected to the plurality of first contacts at one end; and a drive member having a plurality of output terminals that each output a drive signal, each of which is connected to the other end of the plurality of wires, wherein two or more of the plurality of second contacts are connected to one of the plurality of first contacts. [Effects of the Invention]

[0007] The liquid discharge head of the present invention is configured to output a drive signal to each individual electrode from multiple output terminals of the drive member. In other words, when driving the actuator member at high speed, a drive signal can be output to a single individual electrode via multiple wiring (transmission paths). As a result, the quality of the drive signal output to the individual electrodes from the drive member can be maintained. [Brief explanation of the drawing]

[0008] [Figure 1] This is a plan view of a printer including a print head according to the first embodiment of the present invention. [Figure 2] This is a perspective view of the head. [Figure 3] Figure 2 shows a cross-sectional view of the head along the line III-III. [Figure 4] This is an unfolded view of the COF (Chip of Fiber) contained in the head, seen from the underside. [Figure 5] This is a plan view of the flow path component and actuator component included in the head. [Figure 6] This is a cross-sectional view along the line VI-VI shown in Figure 5. [Figure 7] This is an enlarged view of region VII shown in Figure 4. [Figure 8] This graph shows the drive signals output by the head's driver IC. [Figure 9] This is a block diagram showing the electrical configuration of the printer in Figure 1. [Figure 10] This graph shows the drive signals output by the head driver IC according to the second embodiment of the present invention. [Figure 11] This graph shows the drive signals output by the head driver IC according to the third embodiment of the present invention. [Figure 12] This is an enlarged view of region VII of the COF of the head according to the fourth embodiment of the present invention. [Modes for carrying out the invention]

[0009] <First Embodiment> The printer 100 shown in FIG. 1 includes a head 10 which is a first embodiment of the "liquid ejection head" according to the present invention. In the following description, the vertical direction is defined based on the state in which the printer 100 is installed for use, the front-rear direction is defined with the downstream side in the conveyance direction of the paper 9 as the front, and the left-right direction is defined when viewed from the front of the printer 100. The front-rear direction corresponds to the "first direction" of the present invention, and the left-right direction corresponds to the "second direction" of the present invention.

[0010] The printer 100 includes a head 10, a carriage 11 that holds the head 10, a scanning mechanism 30 that moves the carriage 11 and the head 10 in a scanning direction parallel to the left-right direction, a platen 7 that supports the paper 9 from below, a conveyance mechanism 70 that conveys the paper 9 forward, and a control unit 8.

[0011] The scanning mechanism 30 includes a pair of guides 31, 32 that support the carriage 11, and a belt 33 that is connected to the carriage 11. The guides 31, 32 and the belt 33 extend in the left-right direction. When a carriage motor 30M (see FIG. 9) is driven under the control of the control unit 8, the belt 33 runs, and the carriage 11 and the head 10 move in the scanning direction along the guides 31, 32.

[0012] The platen 7 is disposed below the carriage 11 and the head 10. The paper 9 is supported on the upper surface of the platen 7.

[0013] The conveyance mechanism 70 has a roller 71 disposed behind the head 10 and a roller 72 disposed in front of the head 10. The head 10, the carriage 11, and the platen 7 are disposed between the roller 71 and the roller 72 in the front-rear direction.

[0014] The rollers 71, 72 are each composed of a set of rotating members. The set of rotating members includes an upper rotating member disposed above the conveyance path of the paper 9 and a lower rotating member disposed below the conveyance path of the paper 9. The upper rotating member and the lower rotating member are disposed such that their circumferential surfaces are in contact with each other.

[0015] When the conveyance motor 70M (see FIG. 9) is driven under the control of the control unit 8, each rotating member of the rollers 71 and 72 rotates. As each rotating member of the rollers 71 and 72 rotates while sandwiching the paper 9, the paper 9 is conveyed forward.

[0016] As shown in FIGS. 2 to 6, the head 10 includes a flow path member 12, an actuator member 13, a COF 14, driver ICs 15A and 15B, and a frame 19. The COF 14 corresponds to the "wiring member" of the present invention. The driver ICs 15A and 15B are mounted on the COF 14 and are electrically connected to the control unit 8 (see FIG. 9). The driver ICs 15A and 15B correspond to the "driving member" of the present invention.

[0017] As shown in FIG. 2, the flow path member 12, the actuator member 13, and the frame 19 are rectangular in shape and long in the front-rear direction in a plane orthogonal to the vertical direction. As shown in FIG. 6, a plurality of nozzles 123 are formed in the lower surface of the flow path member 12. Inside the flow path member 12, a common flow path 121 and individual flow paths 122 for each nozzle 123 are formed. The individual flow path 122 is a flow path that extends from the outlet of the common flow path 121 through the pressure chamber 12P to the nozzle 123.

[0018] As shown in FIG. 5, a plurality of pressure chambers 12P are formed in the upper surface 12X of the flow path member 12 in a region where the actuator member 13 is disposed. On the upper surface 12X of the flow path member 12, four openings 129 that communicate with the common flow path 121 are disposed on each of the front and rear sides sandwiching the region where the actuator member 13 is disposed.

[0019] As shown in Figures 2 and 3, the frame 19 is a rectangular frame-shaped member arranged along the periphery of the flow channel member 12, and is positioned around the actuator member 13 on the upper surface 12X of the flow channel member 12. Four openings 191 are provided at the front and rear edges of the frame 19. Each opening 191 communicates with the opening 129 of the flow channel member 12 described above, and also communicates with the ink tank via a tube. For example, ink in the ink tank flows into the common flow channel 121 via the tube and the four front openings 191, and returns to the ink tank via the four rear openings 191 and the tube.

[0020] As shown in Figures 3, 5, and 6, the actuator member 13 is positioned on the upper surface 12X of the flow channel member 12 so as to cover a plurality of pressure chambers 12P. As shown in Figure 6, the actuator member 13 includes a metal diaphragm 131 positioned on the upper surface 12X of the flow channel member 12, a piezoelectric layer 132 positioned on the upper surface of the diaphragm 131, and a plurality of individual electrodes 133 positioned on the upper surface of the piezoelectric layer 132 so as to face each of the plurality of pressure chambers 12P. The diaphragm 131 is spaced apart from the individual electrodes 133 in the vertical direction.

[0021] The diaphragm 131 and the multiple individual electrodes 133 are electrically connected to the driver ICs 15A and 15B via the COF 14. The driver ICs 15A and 15B are electrically connected to the control unit 8.

[0022] The upper surface 13X of the actuator member 13 (i.e., the upper surface of the piezoelectric layer 132) has contacts (not shown) electrically connected to the diaphragm 131 and contacts 139 arranged on the upper surfaces of the individual electrodes 133. The COF 14 has contacts 149 electrically connected to each of the contacts 139 arranged on the upper surface 13X, and wiring 142 electrically connecting the contacts 149 to the driver ICs 15A and 15B. The COF 14 also has contacts electrically connected to the contacts electrically connected to the diaphragm 131 of the actuator member 13, and wiring (both not shown) electrically connecting these contacts to the driver ICs 15A and 15B. Contact 139 corresponds to the "first contact" of the present invention, and contact 149 corresponds to the "second contact" of the present invention.

[0023] The driver ICs 15A and 15B, under the control of the control unit 8, maintain the potential of the diaphragm 131 at ground potential while changing the potential of the individual electrodes 133. Specifically, the driver ICs 15A and 15B generate drive signals based on control signals (waveform signal FIRE and selection signal SIN) from the control unit 8 and supply the drive signals to the individual electrodes 133 via the wiring 142. As a result, the potential of the individual electrodes 133 changes between a predetermined drive potential and ground potential.

[0024] The drive signal includes ejection drive signals Sa0 and Sa1, as shown in Figure 8. Ejection drive signals Sa0 and Sa1 correspond to the amount of ink ejected from nozzle 123 per unit time (one ejection cycle from time t0 to time t1), T. Unit time T is the time required for the paper 9 to move relative to the head 10 by a unit distance corresponding to the resolution of the image formed on the paper 9, and corresponds to one dot (one pixel).

[0025] The ejection drive signal Sa0, corresponding to a "zero" ejection amount, contains no pulses within a unit time T and does not eject ink from the nozzle 123. The ejection drive signal Sa1, corresponding to a desired ejection amount, contains two pulses P1 and P2 within a unit time T and ejects the desired amount of ink from the nozzle 123. The two pulses P1 and P2 are rectangular pulses and have the same pulse width. However, the shape of the pulses is not limited to rectangular.

[0026] In this embodiment, in the initial state, a driving potential VDD is applied to the individual electrodes 133, and the actuator 130 (see Figure 6), which is the portion sandwiched between each individual electrode 133 and each pressure chamber 12P in the diaphragm 131 and piezoelectric layer 132, is deformed convex toward the pressure chamber 12P.

[0027] The ejection drive signal Sa0 maintains the individual electrode 133 at the drive potential VDD (i.e., the actuator 130 maintains a convex deformation toward the pressure chamber 12P). With the ejection drive signal Sa1, at the timing when the individual electrode 133 is at ground potential, the actuator 130 becomes flat, and the volume of the pressure chamber 12P increases from the initial state. At this time, ink is drawn from the common flow path 121 into the individual flow path 122. Subsequently, at a predetermined timing, the drive potential VDD is again applied to the individual electrode 133, and the actuator 130 deforms convex toward the pressure chamber 12P, causing the ink pressure to rise due to the decrease in the volume of the pressure chamber 12P, and ink is ejected from the nozzle 123.

[0028] Furthermore, the actuator 130 is provided for each individual electrode 133 (i.e., each nozzle 123), and can be independently deformed according to the potential supplied to the individual electrode 133.

[0029] As shown in Figure 3, COF14 includes a connecting portion 14X positioned on the upper surface 13X of the actuator member 13, and two extension portions 14Y extending from the front end 14X1 and rear end 14X2 of the connecting portion 14X in the front-rear direction. The connecting portion 14X extends parallel to the upper surface 13X, along the front-rear and left-right directions. Multiple contacts 149 (see Figure 4) are positioned on the lower surface of the connecting portion 14X. The connecting portion 14X corresponds to the "opposing portion" of the present invention.

[0030] Each of the two extension sections 14Y includes a vertical section extending upward from the front end 14X1 or rear end 14X2 of the connecting section 14X, and a horizontal section extending rearward or forward from the upper end of the vertical section toward the center of the head 10 in the front-rear direction. Of the two extension sections 14Y, the driver IC 15A is positioned on the upper surface of the horizontal section of the front extension section 14Y, and the driver IC 15B is positioned on the upper surface of the horizontal section of the rear extension section 14Y.

[0031] As shown in Figure 3, the actuator member 13 and COF 14 are arranged within the frame 19. The pressing member 18, support member 16, and circuit board 17 are arranged in the space enclosed by the connection portion 14X and the two extension portions 14Y of the COF 14. The pressing member 18, support member 16, and circuit board 17 are positioned above the connection portion 14X. The vertical portion of the extension portion 14Y is positioned along the side surface of the pressing member 18.

[0032] As shown in Figure 3, the lower surface of the pressing member 18 is positioned with a gap between it and the region 13R on the upper surface 13X of the actuator member 13 where multiple individual electrodes 133 (see Figure 5) are arranged, and the connecting portion 14X connected to the region 13R. The peripheral edge of the lower surface of the pressing member 18 contacts the connecting portion 14X, pressing the connecting portion 14X downward toward the actuator member 13.

[0033] The support member 16 is supported from below by the pressing member 18 and supports three circuit boards 17 on its lower surface. The circuit boards 17 are placed in recesses provided on the upper surface of the pressing member 18 and are electrically connected to the COF 14.

[0034] A sealing material 20 is positioned along the inner periphery of the frame 19. The sealing material 20 isolates the space between the connection portion 14X and the actuator member 13 from the outside space. This prevents ion migration between the individual electrodes 133 caused by moisture from the atmosphere entering the space. The sealing material 20 may be made of a non-conductive material such as fluororesin.

[0035] As shown in Figure 4, COF14 has a rectangular base material 141 that defines the outer shape of COF14. The base material 141 is provided across the connecting portion 14X and the two lead-out portions 14Y. The base material 141 is made of a flexible and insulating material such as polyimide.

[0036] Multiple wires 142 and multiple contacts 149 are arranged on the substrate 141. Each wire 142 is arranged across a connection portion 14X and two lead portions 14Y, and extends from either the driver IC 15A or 15B located in the lead portion 14Y to the corresponding contact 149 located in the connection portion 14X. A contact 149 is located at one end (tip) of each wire 142, and the other end of each wire 142 is connected to either the output terminal 15A1 or 15B1 (see Figure 9) of the driver IC 15A or 15B.

[0037] In this embodiment, the multiple wires 142 are electrically connected in pairs to one contact 139. Therefore, the contacts 149 of two wires 142 connected to the same contact 139 are a common single contact 149. In other words, two wires 142 connected to the same contact 139 each have a common contact 149 at one end. Alternatively, a contact may be provided at one end of each wire 142, and two contacts 149 may be connected to the contact 139. The wires 142 and contacts 149 may be made of any conductive material.

[0038] As shown in Figure 4, COF14 has a wiring region A on a substrate 141 in which a plurality of wires 142 are arranged, and a contact region B which is an area other than wiring region A in which a plurality of contacts 149 are arranged. In wiring region A, the plurality of wires 142 are arranged in the left-right direction.

[0039] Wiring area A is located across the connection section 14X and the two lead-out sections 14Y. On the other hand, contact area B is located on the connection section 14X and not on the lead-out sections 14Y.

[0040] In the connection portion 14X, a total of 12 contact areas B are arranged with spacing in the left-right direction. Each contact area B extends in the front-back direction. Multiple contacts 149 are arranged in two rows in a staggered pattern along the front-back direction in the area of ​​the contact area B excluding both ends in the front-back direction.

[0041] The wiring area A provided in the connection portion 14X includes an outer edge A1 along the front end 14X1 of the connection portion 14X, an outer edge A2 along the rear end 14X2 of the connection portion 14X, and a plurality of clamping portions A3 that sandwich the contact area B in the left-right direction.

[0042] The outer edge A1 extends in the left-right direction and contacts the front ends of the multiple contact areas B. The outer edge A2 extends in the left-right direction and contacts the rear ends of the multiple contact areas B. The clamping portion A3 extends in the front-back direction, similar to the contact areas B.

[0043] Here, we will describe the multiple wires 142. As shown in Figure 7, each wire 142 has a first portion 142A located in the wiring area A and a second portion 142B connecting the first portion 142A and the contact 149. The first portion 142A extends in the front-rear direction within the clamping portion A3 of the wiring area A in the connection portion 14X.

[0044] The first portion 142A of the wiring 142 connected to the contact 149 belonging to the rightmost of the two columns located in contact area B is all located in the clamping portion A3 to the right of the contact 149. On the other hand, the first portion 142A of the wiring 142 connected to the contact 149 belonging to the leftmost column is all located in the clamping portion A3 to the left of the contact 149. As a result, the second portion 142B of the wiring 142 connected to the contact 149 belonging to the rightmost column is connected to the first portion 142A located in the rightmost of the two clamping portions A3, and the second portion 142B of the wiring 142 connected to the contact 149 belonging to the leftmost column is connected to the first portion 142A located in the leftmost of the two clamping portions A3.

[0045] Of the two second parts 142B connected to the same contact 149, the second part 142B on the front side (one side in the front-rear direction) in Figure 7 has a part 142B1 extending in the front-rear direction and a connecting part 142B2 connecting the part 142B1 and the first part 142A. On the other hand, the second part 142B on the rear side (the other side in the front-rear direction) in Figure 7 is, in this embodiment, composed of a connecting part that extends in a cross direction intersecting the front-rear and left-right directions and connects the contact 149 and the first part 142A, but it may also have a part that extends in the front-rear direction.

[0046] In this configuration, one of the two wires 142 connected to each contact 149 located in contact area B has an extended portion 142B1. This extended portion 142B1 exists in the left-right direction between the boundary between the clamping portion A3 where the first portion 142A is located and contact area B, and the contact 149.

[0047] A solder resist layer 146, made of a non-conductive material, is placed on the substrate 141 so as to cover the wiring 142. The solder resist layer 146 is placed in areas other than the contact area B, i.e., the wiring area A, and covers substantially the entire lower surface of the substrate 141.

[0048] As shown in Figure 9, the control unit 8 includes a CPU 81, a ROM 82, a RAM 83, and an ASIC 84. The ROM 82 stores programs and data for the CPU 81 and ASIC 84 to perform various controls. The RAM 83 temporarily stores data (image data, etc.) used by the CPU 81 and ASIC 84 when executing programs. The control unit 8 is connected to an external device (personal computer, etc.) 85 for communication, and the CPU 81 and ASIC 84 perform recording processing, etc., based on data input from the external device 85 or the input section of the printer 100 (switches and buttons provided on the outside of the printer 100's casing). The ASIC 84 is electrically connected to driver ICs 15A and 15B, a carriage motor 30M, and a transport motor 70M.

[0049] In the recording process, the ASIC84, in accordance with commands from the CPU81 and based on recording commands received from external devices 85, drives the driver ICs 15A and 15B, the carriage motor 30M, and the transport motor 70M to alternately perform a transport operation in which the transport mechanism 70 transports a predetermined amount of paper 9 in the transport direction, and a scanning operation in which the head 10 moves in the scanning direction while ejecting ink from the nozzles 123. As a result, ink dots are formed on the paper 9, and an image is recorded.

[0050] The ASIC84 includes an output circuit 84A and a transfer circuit 84B. The output circuit 84A generates the waveform signal FIRE and the selection signal SIN, and outputs these signals to the transfer circuit 84B at each discharge cycle. The waveform signal FIRE is a serial signal formed by serializing two discharge drive signals Sa0 and Sa1 (see Figure 8).

[0051] The selection signal SIN is a serial signal containing selection data for selecting one of two discharge drive signals Sa0 and Sa1, and is generated for each actuator 130 and each discharge cycle based on the image data included in the recording command.

[0052] The transfer circuit 84B transfers the waveform signal FIRE and the selection signal SIN received from the output circuit 84A to the driver ICs 15A and 15B. The transfer circuit 84B has a built-in Low Voltage Differential Signaling (LVDS) driver corresponding to each signal, and transfers each signal as a pulsed differential signal to the driver ICs 15A and 15B.

[0053] In the recording process, ASIC84 controls driver ICs 15A and 15B to generate ejection drive signals Sa0 and Sa1 for each pixel (dot) based on the waveform signal FIRE and the selection signal SIN. The driver ICs 15A and 15B then supply the ejection drive signals Sa0 and Sa1 to the individual electrodes 133 via wiring 142 from their output terminals 15A1 and 15B1. More specifically, driver ICs 15A and 15B output the same drive signal (either ejection drive signal Sa0 or Sa1) at the same time to each individual electrode 133 via two wires 142, each having a contact 149 connected to the same contact 139. In other words, driver ICs 15A and 15B output the same drive signal at the same time to two contacts 149 (a common contact 149) connected to the same contact 139. Therefore, each individual electrode 133 receives the same drive signal from driver ICs 15A and 15B via the two wires 142. In this way, the ASIC84 ejects ink from each of the multiple nozzles 123 for each pixel, with an amount of ink selected from the available ejection amounts (zero, desired amount) directed toward the paper 9.

[0054] As described above, in the head 10 of this embodiment, each contact 139 is connected to a contact 149 at one end of two wires 142, the other ends of which are connected to the output terminals 15A1 and 15B1 of the driver ICs 15A and 15B, respectively. This configuration allows drive signals to be output to each individual electrode 133 from two of the multiple output terminals 15A1 and 15B1 of the driver ICs 15A and 15B. In other words, when driving the actuator member 13 at high speed, a drive signal can be output to one individual electrode 133 via two wires 142 (transmission paths). As a result, the quality of the drive signals output to the individual electrodes 133 from the driver ICs 15A and 15B can be maintained.

[0055] Driver ICs 15A and 15B output the same drive signal at the same timing to two contacts 149 (one common contact 149) connected to the same contact 139. As a result, two identical drive signals are output to one contact 139 (individual electrode 133). If a drive signal were supplied to one individual electrode 133 via one wiring 142, the transmission path would be one wiring 142. If there is a relatively large loss in this wiring 142, this loss may affect the quality of the drive signal to the individual electrode 133, such as causing the drive potential in the drive signal to be lower than the predetermined potential. However, in this configuration, a drive signal is supplied to one individual electrode 133 from each of the two wirings 142. In other words, a high-quality drive signal is supplied to the individual electrode 133 from the wiring 142 with the lower loss, thus maintaining the quality of the drive signal to the individual electrode 133. Therefore, the desired voltage can be applied to one individual electrode 133, and the current supply capability is also improved.

[0056] Of the two second parts 142B connected to the two contacts 149 connected to the same contact 139, one of the second parts 142B has an extended portion 142B1. As a result, when forming the solder resist layer 146 of the COF 14, even if the material constituting the solder resist layer 146 (solder resist) tries to flow from the wiring area A to the contact area B, the portion 142B1 extending in the front-to-back direction of the second part 142B acts as a barrier, suppressing the progress of such flow. Therefore, it is possible to prevent multiple contacts 149 from being covered by the solder resist layer 146.

[0057] <Second Embodiment> Next, with reference to Figure 10, a head 10 according to a second embodiment of the present invention will be described. In this embodiment, the drive signals output from the output terminals 15A1 and 15B1 of the driver ICs 15A and 15B, respectively, include a discharge drive signal Sa2 in addition to the discharge drive signals Sa0 and Sa1 of the first embodiment. The discharge drive signal Sa2 includes two rectangular cancellation pulses CP1 and CP2 within a unit time T. These cancellation pulses CP1 and CP2 have different application timings within a unit time T than pulses P1 and P2 in the discharge drive signal Sa1. More specifically, the cancellation pulse CP1 is applied after pulse P1 and before pulse P2 in the discharge drive signal Sa1, and the cancellation pulse CP2 is applied after pulse P2 in the discharge drive signal Sa1. The cancellation pulses CP1 and CP2 both have the same pulse width, which is smaller than pulses P1 and P2. These cancellation pulses CP1 and CP2, by supplying ejection drive signals Sa1 and Sa2 to the same individual electrode 133 at the same timing, make it possible to suppress satellites and mist of ink ejected from the nozzle 123 by the ejection drive signal Sa1.

[0058] Pulses P1 and P2 correspond to the "first pulse" of the present invention, and cancellation pulses CP1 and CP2 correspond to the "second pulse" of the present invention. Discharge drive signal Sa1 corresponds to the "first drive signal" of the present invention, and discharge drive signal Sa2 corresponds to the "second drive signal" of the present invention.

[0059] In this embodiment, the ASIC84 controls the driver ICs 15A and 15B during the recording process to generate ejection drive signals Sa0, Sa1, and Sa2 for each pixel (dot) based on the waveform signal FIRE and the selection signal SIN. The ASIC84 then supplies the ejection drive signals Sa0, Sa1, and Sa2 to the individual electrodes 133 via the wiring 142 from the output terminals 15A1 and 15B1 of the driver ICs 15A and 15B.

[0060] More specifically, the driver ICs 15A and 15B output the same discharge drive signal Sa0 at the same timing to two wires 142, each having a contact 149 connected to the same contact 139, for each individual electrode 133 that outputs the discharge drive signal Sa0.

[0061] On the other hand, the driver ICs 15A and 15B output the ejection drive signal Sa1 to one of two wires 142, each having a contact 149 connected to the same contact 139, and the ejection drive signal Sa2 to the other wire 142, at the same timing. In other words, the driver ICs 15A and 15B output two ejection drive signals, Sa1 and Sa2, at the same timing to the two contacts 149 connected to the same contact 139. As a result, a combined drive signal, consisting of the ejection drive signal Sa1 and the ejection drive signal Sa2, is output to one individual electrode 133. If, when achieving high-speed driving of the actuator 130, the combined drive signal is output as a single drive signal to one individual electrode 133 via one transmission path (wire 142), the switching of potentials by pulses P1, P2 and cancellation pulses CP1, CP2 may not keep up, and the desired ink ejection may not be achieved. However, in this configuration, when the discharge drive signal Sa1 and discharge drive signal Sa2 are output to the contact 149 via different wiring 142 and a combined drive signal is output to one individual electrode 133, a margin is created in the timing of the potential switching caused by pulses P1 and P2 in the discharge drive signal Sa1 and cancellation pulses CP1 and CP2 in the discharge drive signal Sa2. This makes it possible to reliably execute the potential switching caused by pulses P1 and P2 and cancellation pulses CP1 and CP2, and maintain the quality of the drive signal. In other words, high-speed driving of the actuator 130 becomes possible.

[0062] <Third Embodiment> Next, with reference to Figure 11, a head 10 according to a third embodiment of the present invention will be described. In this embodiment, the head 10 includes, in addition to the ejection drive signal Sa0 of the first embodiment, ejection drive signals Sa3 and Sa4, which are output from the output terminals 15A1 and 15B1 of the driver ICs 15A and 15B, respectively. The ejection drive signal Sa3 includes one pulse P3 and one cancellation pulse CP3 applied after pulse P3 within a unit time T. Both pulse P3 and cancellation pulse CP3 are rectangular pulses, and the pulse width of the cancellation pulse CP3 is smaller than that of pulse P3.

[0063] The ejection drive signal Sa4 includes one cancellation pulse CP4 within a unit time T. The cancellation pulse CP4 is a rectangular pulse and is applied at a different timing than pulse P3 and the cancellation pulse CP3 in the ejection drive signal Sa3 within a unit time T. More specifically, the cancellation pulse CP4 is applied after pulse P3 and before the cancellation pulse CP3 in the ejection drive signal Sa3. The cancellation pulse CP4 is also switchable to a different voltage value than pulse P3, switching the potential from the drive potential VDD to half the drive potential VDD (greater than the ground potential). The cancellation pulse CP3 has a pulse width greater than that of the cancellation pulse CP3 but smaller than that of pulse P3. Such a cancellation pulse CP4, when the ejection drive signals Sa3 and Sa4 are supplied to the same individual electrode 133 at the same timing, makes it possible to effectively suppress satellites and mist of ink ejected from the nozzle 123 by the ejection drive signal Sa3.

[0064] Pulse P3 or cancellation pulse CP3 corresponds to the "first pulse" of the present invention, and cancellation pulse CP4 corresponds to the "second pulse" of the present invention. Discharge drive signal Sa3 corresponds to the "first drive signal" of the present invention, and discharge drive signal Sa4 corresponds to the "second drive signal" of the present invention.

[0065] In this embodiment, the ASIC84 controls the driver ICs 15A and 15B during the recording process to generate ejection drive signals Sa0, Sa3, and Sa4 for each pixel (dot) based on the waveform signal FIRE and the selection signal SIN. The ASIC84 then supplies the ejection drive signals Sa0, Sa3, and Sa4 to the individual electrodes 133 via the wiring 142 from the output terminals 15A1 and 15B1 of the driver ICs 15A and 15B.

[0066] More specifically, the driver ICs 15A and 15B output the same discharge drive signal Sa0 at the same timing to two wires 142, each having a contact 149 connected to the same contact 139, for each individual electrode 133 that outputs the discharge drive signal Sa0.

[0067] On the other hand, the driver ICs 15A and 15B output the discharge drive signal Sa3 to one of two wires 142, each having a contact 149 connected to the same contact 139, and the discharge drive signal Sa4 to the other wire 142 at the same time. In other words, the driver ICs 15A and 15B output two discharge drive signals Sa3 and Sa4 at the same time to the two contacts 149 connected to the same contact 139. As a result, a combined drive signal consisting of the discharge drive signal Sa3 and the discharge drive signal Sa4 is output to one individual electrode 133. This provides the same effect as in the second embodiment. Furthermore, a combined drive signal with a complex waveform and different voltage values, consisting of the discharge drive signal Sa3 and the discharge drive signal Sa4, is output to one individual electrode 133.

[0068] <Fourth Embodiment> Next, with reference to Figure 12, a head 10 according to the fourth embodiment of the present invention will be described. In this embodiment, the head 10 has two wires 142, each having a contact 149 (a common contact 149) connected to the same contact 139. The first portion 142A of one of the two wires 142 (for example, the left or right) is positioned in one of the two clamping portions A3 that sandwich the contact region B (for example, the left or right), and the first portion 142A of the other wire 142 (for example, the right or left) is positioned in the other clamping portion A3 (for example, the right or left). These wires 142 also have a first portion 142A and a second portion 142B that connects the first portion 142A to the contact 149.

[0069] In this embodiment, the second portion 142B of one of the two wires 142 connected to the common contact 149 is composed of a connecting portion that extends in a crossing direction intersecting the front-to-back and left-to-right directions and connects the contact 149 to the first portion 142A, but it may also have a portion that extends in the front-to-back direction. The second portion 142B of the other wire 142 has a portion 142B1 that extends in the front-to-back direction, a connecting portion 142B2 that connects the extending portion 142B1 to the first portion 142A, and a portion 142B3 that extends in the left-to-right direction that connects the extending portion 142B1 to the contact 149.

[0070] In this configuration, each of the two wires 142 connected to each contact 149 located in the contact area B has an extending portion 142B1 on the other end. This extending portion 142B1 exists in the left-right direction between the boundary between the clamping portion A3 where the first portion 142A is located and the contact area B, and the contact 149. Furthermore, the multiple extending portions 142B1 are arranged in two rows in a staggered pattern along the front-to-back direction in the area of ​​the contact area B excluding both ends in the front-to-back direction.

[0071] Of the two second parts 142B connected to the same contact 139 (a common single contact 149), one of the second parts 142B has an extended portion 142B1. As a result, when forming the solder resist layer 146 of the COF 14, even if the material constituting the solder resist layer 146 (solder resist) tries to flow from the wiring area A to the contact area B, the portion 142B1 extending in the front-to-back direction of the second part 142B acts as a barrier, suppressing the progression of such flow. Therefore, it is possible to prevent multiple contacts 149 from being covered by the solder resist layer 146.

[0072] Although preferred embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and various modifications are possible as long as they are within the scope of the claims.

[0073] In each of the embodiments described above, two contacts 149 (a common contact 149) are connected to one contact 139, but contacts 149 of three or more wirings 142 may be connected to one contact 139. In this case as well, the same effects as in the embodiments described above can be obtained.

[0074] In the first to third embodiments, the pulses and cancellation pulses of the discharge drive signals Sa1 to Sa4 may have an appropriate number of pulses, and the number of pulses is not particularly limited. Furthermore, the shape of the pulses and cancellation pulses may be any shape.

[0075] The electrodes constituting the actuator 130 described above have a two-layer configuration including individual electrodes 133 and a diaphragm 131 (common electrode), but they may also have a three-layer configuration. For example, a three-layer configuration includes a drive electrode to which high potential and low potential are selectively applied, a high-potential electrode that is held at a high potential, and a low-potential electrode that is held at a low potential.

[0076] The type of liquid dispensing head of the present invention is not limited to serial type, but may also be line type.

[0077] The object from which the liquid is discharged from the nozzle 123 is not limited to paper, but may be, for example, cloth, a circuit board, a plastic component, etc.

[0078] The liquid discharged from the nozzle 123 is not limited to ink, but may be any liquid (for example, a processing liquid that causes components in the ink to coagulate or precipitate).

[0079] The present invention is not limited to printers, but can also be applied to facsimile machines, copiers, multifunction devices, etc. Furthermore, the present invention can also be applied to liquid ejection heads used for purposes other than image recording (for example, liquid ejection heads that eject conductive liquid onto a substrate to form a conductive pattern). [Explanation of Symbols]

[0080] 10 heads 12 Flow channel members 12P Pressure Chamber 13 Actuator Member 13X top 14 COF 14X Connection part 15A, 15B driver IC 15A1,15B1 Output end 133 Individual electrodes 139 Contacts 141 Base material 142 Wiring 142A Part 1 142B 2nd part 142B1 Extending part 146 Solder Resist Layers 149 Contacts A wiring area A3 clamping part B contact area CP1~CP4 Cancel Pulse P1~P3 pulses

Claims

1. A flow channel member having multiple pressure chambers, An actuator member disposed on the upper surface of the flow channel member, having a plurality of individual electrodes that overlap each of the plurality of pressure chambers in the vertical direction, and a plurality of first contacts disposed on the upper surface and connected to each of the plurality of individual electrodes, A wiring member disposed on the upper surface of the actuator member, having a plurality of wires, each having a plurality of second contacts connected to the plurality of first contacts, A drive member having a plurality of output terminals that each output a drive signal, wherein each of the plurality of output terminals is connected to the other end of the plurality of wirings, A liquid dispensing head characterized in that two or more of the multiple second contacts are connected to one of the multiple first contacts.

2. The drive signal includes one or more pulses within one ejection cycle for forming one dot. The liquid dispensing head according to claim 1, characterized in that the drive member outputs the same drive signal at the same timing to a plurality of second contacts connected to the same first contact.

3. The drive signal includes a first drive signal that includes one or more first pulses within one discharge cycle for forming one dot, and a second drive signal that includes one or more second pulses within one discharge cycle that are at a different timing than the first pulse in the first drive signal. The liquid discharge head according to claim 1, characterized in that the drive member outputs a first drive signal to one of a plurality of second contacts connected to the same first contact, and outputs a second drive signal to another second contact of the plurality of second contacts at the same timing as the first drive signal.

4. The drive signal includes a first drive signal that includes one or more first pulses within one discharge cycle for forming one dot, and a second drive signal that includes one or more second pulses within one discharge cycle that have a different timing and voltage value than the first pulse in the first drive signal. The liquid discharge head according to claim 1, characterized in that the drive member outputs a first drive signal to one of a plurality of second contacts connected to the same first contact, and outputs a second drive signal to another second contact of the plurality of second contacts at the same timing as the first drive signal.

5. The portion of the wiring member that faces the actuator member in the vertical direction has a wiring region in which the plurality of wires are arranged in a first direction perpendicular to the vertical direction and a second direction intersecting both the vertical direction and the first direction, and a contact region other than the wiring region in which the plurality of second contacts are arranged. The wiring member further includes a substrate on which the plurality of second contacts and the plurality of wirings are arranged, and a solder resist layer disposed on the substrate so as to cover the plurality of wirings arranged in the wiring region. The wiring includes a first portion arranged in the wiring area and a second portion connecting the first portion and the second contact. The wiring region includes two clamping portions that sandwich the contact region in the second direction, The liquid discharge head according to claim 1, wherein the plurality of second portions connected to the same first contact connect the first portion and the second contact, and at least one of the second portions has a portion extending in the first direction.

6. The portion of the wiring member that faces the actuator member in the vertical direction has a wiring region in which the plurality of wires are arranged in a first direction perpendicular to the vertical direction and a second direction intersecting both the vertical direction and the first direction, and a contact region other than the wiring region in which the plurality of second contacts are arranged. The wiring member further includes a substrate on which the plurality of second contacts and the plurality of wirings are arranged, and a solder resist layer disposed on the substrate so as to cover the plurality of wirings arranged in the wiring region. The wiring includes a first portion arranged in the wiring area and a second portion connecting the first portion and the second contact. The wiring region includes two clamping portions that sandwich the contact region in the second direction, The liquid discharge head according to claim 1, characterized in that one of the plurality of second parts connected to the same first contact connects the first part located on one of the two clamping parts to the second contact, another second part of the plurality of second parts connects the first part located on the other of the two clamping parts to the second contact, and at least one of the second parts has a portion extending in the first direction.

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