JP2006315218A - Liquid ejection head and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem that the cost increases when a flexible flat cable is employed for connecting the flexible substrate of a recording head and an interconnection substrate arranged in a carriage because pin arrangement on one side is reversed. <P>SOLUTION: In a recording head 7 integrating a head 101 and a tank 102 for supplying recording liquid to the head 101, the tank 102 is made of resin and a signal line 103 transmitting a signal for driving a pressure generating means of the head 101 is formed on the outer surface of the tank 102. The other end of the signal line 103 is connected with a connector 104 which is connected electrically with an interconnection substrate 105 provided in the carriage 3. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a liquid discharge head and an image forming apparatus, and more particularly to a tank integrated liquid discharge head and an image forming apparatus including the tank integrated liquid discharge head.

  For example, as an image forming apparatus such as a printer, a facsimile, a copying apparatus, or a plotter, an ink jet recording apparatus using a liquid discharge head that discharges a recording liquid droplet as the recording head is known. As such a liquid discharge head, for example, a diaphragm that forms a wall surface of an ink flow path is deformed by using an electromechanical conversion element such as a piezoelectric element as pressure generating means for pressurizing ink in a pressurized liquid chamber. A so-called piezo type that discharges ink droplets by changing the volume in the flow path, a so-called thermal type that utilizes film boiling of the recording liquid using an electrothermal transducer such as a heating resistor, and the wall surface of the ink flow path Electrostatic force that changes the volume of the ink flow path and ejects ink droplets by deforming the diaphragm with electrostatic force generated between the diaphragm and the electrode. There are known a type and a shape memory alloy actuator using a metal phase change due to a temperature change as a pressure generating means.

  In such an ink jet recording apparatus using a liquid discharge head or a liquid discharge head, in order to drive the pressure generation means of the liquid discharge head in accordance with the recording data, the apparatus main body side with respect to the pressure generation means of the liquid discharge head Therefore, it is necessary to provide wiring for supplying a required signal.

Therefore, for example, as described in Patent Document 1, a flexible substrate on which a drive IC for driving a recording head and the like are mounted and a relay substrate disposed in a carriage on which the recording head is mounted are used using a flexible flat cable. An ink jet recording apparatus to be connected is known.
JP 2004-351727 A

In addition, as described in Patent Document 2, a head body having a discharge energy generation unit that generates discharge energy, a support member that supports the head body, and a power source that supplies driving power to the energy generation means There is known a liquid discharge head including a flexible printed wiring board for electrically connecting the head and the head body.
JP 2002-026471 A

Further, as described in Patent Document 3, a carriage movable in the main scanning direction is disposed above the conveyance surface of the recording paper, a print head and a relay board are mounted on the carriage, and the print head and the relay board are mounted. 2. Description of the Related Art There is known an ink jet recording apparatus that includes an FPC that is electrically connected and is arranged so that the FPC is pulled out from a print head in the main scanning direction, bent about 180 °, and folded in a carriage.
JP 2002-053940 A

In addition to the above, those using a relay substrate are also described in Patent Documents 4 to 13.
JP 2003-127390 A JP 2003-127342 A JP 2003-127343 A JP 2003-127344 A JP 2003-127391 A JP 2003-127392 A JP 2003-127348 A JP 2003-127405 A Japanese Patent Laid-Open No. 2003-181352 JP 2003-246072 A

In addition to the above, those using flexible flat cables and relay boards include those described in Patent Documents 14 to 18.
JP 2003-305843 A JP 2004-098630 A JP 2004-268454 A JP 2000-071552 A JP-A-62-045827

  As described above, since a flexible substrate is generally expensive, an inexpensive flexible flat cable is used for a portion where the wiring is extended and pulled out between the carriage and the apparatus main body. However, the flexible flat cable has an electrode pitch. It is currently used only when there is 1 mm or more.

  Also, in a full-color inkjet recording apparatus in which a plurality of heads having a plurality of nozzles arranged in multiple rows are mounted, when connecting the flexible substrate of the recording head and the relay substrate arranged in the carriage, the pin arrangement on one side However, there is a problem that the cost of the relay board is increased. Furthermore, the pattern layout of the relay substrate arranged in the carriage becomes complicated, and there is a problem that the prescribed pattern width cannot be secured and the reliability may be lowered. Further, when connecting the flexible flat cable to the connector of the relay board, it takes time to assemble and cannot be easily connected, so that there is a problem that the assembling work is troublesome.

  SUMMARY An advantage of some aspects of the invention is that it provides a tank-integrated liquid discharge head and an image forming apparatus in which wiring to the head is simplified.

  In order to solve the above problems, a liquid discharge head according to the present invention is a tank-integrated liquid discharge head in which a head for discharging a droplet of recording liquid and a tank for supplying recording liquid to the head are integrated. A signal line made of a resin member and having one end connected to the head is formed on the outer surface of the tank.

  Here, the other end of the signal line formed in the tank is provided in a carriage on which the liquid discharge head is mounted, and is electrically connected to a relay substrate that is electrically connected to the apparatus main body. It is preferable that it is connected to the connection means.

  The image forming apparatus according to the present invention includes the tank-integrated liquid discharge head according to the present invention.

  Here, it is preferable that the tank-integrated liquid discharge head is detachably attached to the apparatus main body.

  According to the liquid ejection head and the image forming apparatus of the present invention, the tank integrated with the head is made of a resin member, and a signal line having one end connected to the head is formed on the outer surface of the tank. Therefore, the wiring for the head is simplified and the cost can be reduced.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. An example of the image forming apparatus according to the present invention provided with the liquid discharge head according to the present invention will be described with reference to FIGS. FIG. 1 is an explanatory side view for explaining the overall configuration of the image forming apparatus, and FIG. 2 is an explanatory plan view of a main part of the apparatus.

  In this image forming apparatus, a carriage 3 is slidably held in a main scanning direction by a guide rod 1 and a guide rail 2 which are guide members horizontally mounted on left and right side plates (not shown), and a driving pulley 6A is driven by a main scanning motor 4. 2 is moved and scanned in the direction of the arrow (main scanning direction) in FIG. 2 via the timing belt 5 spanned between the driven pulley 6B.

  For example, an independent tank-integrated liquid discharge head that discharges droplets (ink droplets) of recording liquids of each color of black (K), cyan (C), magenta (M), and yellow (Y) is provided on the carriage 3. 7k, 7c, 7m, 7y (hereinafter referred to as “recording head 7” when colors are not distinguished) are arranged in a direction along the main scanning direction, and are detachably mounted with the droplet discharge direction facing downward. Yes.

  On the other hand, as a paper feeding unit for feeding paper 12 stacked on a paper stacking unit (pressure plate) 11 such as a paper feeding cassette 10, a half-moon roller (for separating and feeding the paper 12 one by one from the paper stacking unit 11) A separation pad 14 made of a material having a large friction coefficient is provided facing the sheet feeding roller 13 and the sheet feeding roller 13, and the separation pad 14 is urged toward the sheet feeding roller 13 side.

  As a transport unit for transporting the paper 12 fed from the paper feed unit on the lower side of the recording head 7, a transport belt 21 for transporting the paper 12 by electrostatic adsorption, and a paper feed unit A counter roller 22 for transporting the paper 12 fed through the guide 15 between the transport belt 21 and the paper 12 fed substantially vertically upward is turned approximately 90 ° and copied onto the transport belt 21. A conveying guide 23 for adjusting the pressure and a tip pressing roller 25 urged toward the conveying belt 21 by a pressing member 24. In addition, a charging roller 26 as a charging unit for charging the surface of the transport belt 21 is provided.

  Here, the transport belt 21 is an endless belt, and is stretched between the transport roller 27 and the tension roller 28, and the transport roller 27 rotates from the sub-scanning motor 31 via the timing belt 32 and the timing roller 33. By doing so, it is configured to circulate in the belt conveyance direction (sub-scanning direction) of FIG. A guide member 29 is disposed on the back side of the conveying belt 21 corresponding to the image forming area by the recording head 7.

  Further, as shown in FIG. 2, a slit disk 34 is attached to the shaft of the transport roller 27, and a sensor 35 for detecting the slit of the slit disk 34 is provided. An encoder 36 is configured.

  The charging roller 26 is disposed so as to contact the surface layer of the conveyor belt 21 and rotate following the rotation of the conveyor belt 21, and applies 2.5N to both ends of the shaft as a pressing force.

  Further, as a paper discharge unit for discharging the paper 12 recorded by the recording head 7, a separation unit for separating the paper 12 from the conveyance belt 21, a paper discharge roller 52 and a paper discharge roller 53, and paper discharge And a paper discharge tray 54 for stocking the paper 12 to be stored.

  A double-sided paper feeding unit 55 is detachably mounted on the back. The double-sided paper feeding unit 55 takes in the paper 12 returned by the reverse rotation of the transport belt 21, reverses it, and feeds it again between the counter roller 22 and the transport belt 21.

  Further, as shown in FIG. 2, a maintenance / recovery mechanism 56 for maintaining and recovering the nozzle state of the recording head 7 is disposed in the non-printing area on one side of the carriage 3 in the scanning direction.

  This maintenance / recovery machine 596 is configured to discharge each of the caps 57 for capping each nozzle surface of the recording head 7, the wiper blade 58 which is a blade member for wiping the nozzle surface, and the recording liquid having increased viscosity. An empty discharge receiver 59 for receiving droplets when performing empty discharge for discharging droplets that do not contribute to recording is provided.

  In the image forming apparatus configured as described above, the sheets 12 are separated and fed one by one from the sheet feeding unit, and the sheet 12 fed substantially vertically upward is guided by the guide 15, and includes the transport belt 21 and the counter roller 22. The leading end is guided by the conveying guide 23 and pressed against the conveying belt 21 by the leading end pressing roller 25, and the conveying direction is changed by approximately 90 °.

  At this time, a positive voltage output and a negative output are alternately repeated from the AC bias supply unit to the charging roller 26 by a control circuit (not shown), that is, a charging voltage pattern in which an alternating voltage is applied and the conveying belt 21 alternates. That is, plus and minus are alternately charged in a band shape with a predetermined width in the sub-scanning direction which is the circumferential direction. When the sheet 12 is fed onto the conveyance belt 21 charged alternately with plus and minus, the sheet 12 is attracted to the conveyance belt 21 by electrostatic force, and the sheet 12 is conveyed in the sub-scanning direction by the circular movement of the conveyance belt 21. Is done.

  Therefore, by driving the recording head 7 according to the image signal while moving the carriage 3 in the forward and backward directions, ink droplets are ejected onto the stopped paper 12 to record one line. After transporting a predetermined amount, the next line is recorded. Upon receiving a recording end signal or a signal that the trailing edge of the paper 12 has reached the recording area, the recording operation is finished and the paper 12 is discharged onto the paper discharge tray 54.

  In the case of double-sided printing, when recording on the front surface (surface to be printed first) is completed, the recording paper 12 is fed into the double-sided paper feeding unit 55 by rotating the conveyor belt 21 in reverse. The paper 12 is reversed (with the back surface being the printing surface), fed again between the counter roller 22 and the transport belt 21, controlled in timing, and transported onto the transport bell 21 as described above. After recording on the back side, the sheet is discharged onto the discharge tray 54.

  During printing (recording) standby, the carriage 3 is moved to the maintenance / recovery mechanism 55 side, and the nozzle surface of the recording head 7 is capped by the cap 57, and the nozzles are kept in a wet state. To prevent. In addition, the recording liquid is sucked from the nozzle in a state where the recording head 7 is capped by the cap 57 (referred to as “nozzle suction” or “head suction”), and a recovery operation is performed to discharge the thickened recording liquid or bubbles. Wiping is performed by the wiper blade 58 in order to clean and remove ink adhering to the nozzle surface of the recording head 7 by this recovery operation. In addition, an idle ejection operation for ejecting ink not related to recording is performed before the start of recording or during recording. Thereby, the stable ejection performance of the recording head 7 is maintained.

Next, the recording head 7 in this image forming apparatus will be described with reference to FIG. FIG. 3 is a schematic explanatory view of a carriage unit of the image forming apparatus.
The recording head 7 is a tank-integrated liquid discharge head that integrally includes a head 101 that discharges recording liquid droplets and a tank 102 that supplies the recording liquid to the head 101.

  Here, as the head 101, for example, a nozzle in which nozzles for ejecting droplets of recording liquid (ink) are arranged in a two-row zigzag pattern is used. In addition, the head 101 deforms a diaphragm that forms the wall surface of the ink flow path by using an electromechanical conversion element such as a piezoelectric element as pressure generating means for pressurizing the ink in the pressurized liquid chamber, thereby changing the volume of the ink flow path. A so-called piezo-type (piezoelectric) head that discharges ink droplets by changing the pressure is used, but the present invention is not limited to this. As described above, a recording liquid film is formed using an electrothermal conversion element such as a heating resistor. A so-called thermal type that uses boiling, a diaphragm that forms the wall surface of the ink flow path and an electrode are arranged opposite to each other, and the diaphragm is deformed by an electrostatic force generated between the diaphragm and the electrode, thereby providing ink. An electrostatic type that discharges ink droplets by changing the volume in the flow path can also be used.

  Then, the tank 102 of the recording head 7 is formed of a resin member, and a signal line (for transmitting a signal for driving the pressure generating means of the head 101) is applied to the outer surface of the recording head 7 by applying a technique for forming wiring on the resin surface. Wiring) 103 is formed, and one end of the signal line 103 is connected to the head 101 side, and the other end is electrically connected to a relay board 105 provided on the carriage 3 as a contact type (spring type) connector 104. Connected to. Note that the width, length, and the like of the signal line 103 are determined in consideration of actual current consumption. The connector 104 is not limited to a contact type connector.

  As shown in FIG. 4, the relay substrate 105 in the carriage 3 is a connection composed of a plurality of electrode portions 107a to which the FFC 106 on the apparatus body side is connected corresponding to each of the recording heads 7k, 7c, 7m, and 7y. 107k, 107c, 107m, and 107y are provided. The plurality of electrode portions 107a are arranged in a number corresponding to the number of signals to the head 101. Here, since the contact-type connector 104 is connected to the relay substrate 105, the electrode portion 107a is preferably subjected to a treatment such as plating on the surface from the viewpoint of durability and reliability. In addition, the size, shape, and the like of the electrode portion 107a in the relay substrate 105 are assumed to match the specifications of the contact (spring) connector 104 on the tank 102 side of the recording head 7.

  As described above, the head for ejecting the recording liquid droplets and the tank for supplying the recording liquid integrated with the head are made of the resin member, and a signal line having one end connected to the head is formed on the outer surface of the tank. As a result, the wiring for the head can be simplified and the cost can be reduced. In this case, the tank-integrated liquid discharge head can be easily attached to and detached from the apparatus main body by using the relay substrate.

  As described above, the tank-integrated liquid discharge head and the image forming apparatus are not only those in which the tank and the head are interchangeably mounted on the image forming apparatus main body, but also the sub tank and the head are integrated. In some cases, the recording liquid cartridge is mounted on the apparatus main body side in a replaceable manner, and the recording liquid is supplied from the recording liquid cartridge to the sub-tank of the liquid discharge head via a tube. .

FIG. 1 is a side view for explaining the overall configuration of the image forming apparatus according to the present invention. It is principal part plane explanatory drawing of the apparatus. It is a typical explanatory view of the carriage part of the device. It is front explanatory drawing of the relay board | substrate of the carriage.

Explanation of symbols

3 ... carriage 7 ... recording head 101 ... head 102 ... tank 103 ... signal line (wiring)
104 ... Connector 105 ... Relay board

Claims (4)

  In a tank-integrated liquid discharge head in which a head for discharging a recording liquid droplet and a tank for supplying the recording liquid to the head are integrated, the tank is made of a resin member, and one end is formed on the outer surface of the tank. A liquid discharge head, wherein a signal line connected to the head is formed.   2. The liquid discharge head according to claim 1, wherein the other end portion of the signal line formed in the tank is provided in a carriage on which the liquid discharge head is mounted and is electrically connected to the apparatus main body. A liquid discharge head, characterized in that the liquid discharge head is connected to connection means electrically connected to a substrate.   3. An image forming apparatus for forming an image by mounting a liquid discharge head for discharging recording liquid droplets, wherein the liquid discharge head is the tank-integrated liquid discharge head according to claim 1 or 2. Image forming apparatus. 4. The image forming apparatus according to claim 3, wherein the tank-integrated liquid discharge head is detachably attached to the apparatus main body.

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