JP2008143027A - Liquid jet device and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid jet device that can surely suppress a pressure fluctuation in a recording liquid supply path for a recording head in a simple structure, and an image forming apparatus equipped with the liquid jet device. <P>SOLUTION: A recording liquid is supplied to the recording head 34 from an ink cartridge 10 through a supply tube 36, a first pressure fluctuation absorption device 37, and a second pressure fluctuation absorption device 38. The first pressure fluctuation absorption device 37 is provided with a first flexible film member 103 facing a fluid channel 100 and the second pressure fluctuation absorption device 38 is provided with a second flexible film member 113 facing an ink buffer section 110. Faces of the first and second flexible members 103, 113 are respectively coated with damping materials 104, 114, each of the faces being opposite to a face contacting the liquid. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a liquid ejecting apparatus and an image forming apparatus, and more particularly to a liquid ejecting apparatus and an image forming apparatus in which pressure fluctuation in a liquid supply path to a liquid ejecting head is suppressed.

  As an image forming apparatus such as a printer, a facsimile machine, a copying apparatus, and a multifunction machine of these, for example, a liquid ejection apparatus including a recording head composed of a liquid ejection head (droplet ejection head) that ejects liquid droplets of a recording liquid (liquid) As a liquid while transporting a medium (hereinafter also referred to as “paper”, but the material is not limited, and a recording medium, a recording medium, a transfer material, recording paper, etc. are also used synonymously). The recording liquid (hereinafter also referred to as ink) is attached to a sheet to form an image (recording, printing, printing, and printing are also used synonymously).

  The image forming apparatus means an apparatus for forming an image by discharging a liquid onto a medium such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics, etc. The term “not only” means not only giving an image having a meaning such as a character or a figure to a medium but also giving an image having no meaning such as a pattern to the medium. Further, the liquid is not limited to the recording liquid and ink, and is not particularly limited as long as it is a liquid capable of forming an image. Further, the liquid ejection apparatus means an apparatus that ejects liquid from a liquid ejection head, and is not limited to an apparatus that forms an image.

  Such liquid ejecting apparatuses or image forming apparatuses have come to be used for industrial systems such as textile printing apparatuses and metal wiring. In addition, as a liquid ejecting apparatus or an image forming apparatus, a serial type apparatus that mounts a recording head on a carriage, moves the recording head in the main scanning direction, and ejects droplets in the sub-scanning direction, one or more There is known a line type apparatus that discharges liquid droplets while feeding only a sheet while securing the entire area in the width direction of the sheet with a recording head.

  In addition, the liquid discharge head includes a nozzle that discharges droplets, a liquid chamber (also referred to as a pressurized liquid chamber, a discharge chamber, a pressure chamber, a liquid flow path, and the like) that communicates with the nozzle, and a liquid in the liquid chamber. A pressure generating means for generating a pressure to be pressed, and the liquid in the liquid chamber is pressurized with a pressure generated by the pressure generating means, thereby ejecting a droplet from the nozzle. Here, as the pressure generating means, a thermal method using a phase change caused by film boiling of a liquid using an electrothermal transducer such as a heating resistor, a piezoelectric device (in this application, it is used as a synonym for an electromechanical transducer). There are known a piezoelectric method using an electrostatic method, an electrostatic method using an electrostatic actuator that generates an electrostatic force, and the like.

  By the way, especially in the serial type liquid discharge device, a main liquid cartridge that is detachably mounted on the device main body side is connected to a buffer portion (sub tank) mounted on the carriage together with the recording head via a flexible supply tube. Since the liquid is supplied and the liquid is supplied from the buffer unit to the recording head, the pressure fluctuation of the liquid occurs in the supply tube and in the buffer unit as the carriage scans, and the droplet ejection characteristics from the recording head are affected.

Therefore, conventionally, Patent Document 1 discloses a pressure fluctuation suppression film utilizing inertia due to a speed change of a weight carriage joined to a central portion of a pressure fluctuation suppression film provided on a side surface of a concave portion in which ink is accumulated in an ink buffer portion. Is deformed to increase or decrease the amount of ink staying in the ink buffer unit to absorb the pressure fluctuation of the ink in the ink supply tube that occurs when the carriage reciprocates.
JP 2001-121713 A

Patent Document 2 discloses an ink chamber and an ink chamber each having an ink inlet and an ink outlet in a damper structure provided in the middle of an ink supply pipe that supplies ink to an inkjet head that discharges ink from an intermediate tank that stores ink. An air chamber for adjusting the pressure of the ink chamber, a filter at the ink outlet, a flexible film as a partition member for partitioning the ink chamber and the air chamber, and a back pressure applied to the flexible film in the air chamber. It is described that an air pump and an on-off valve are provided as a pressure adjustment mechanism for adjustment.
Japanese Patent Laid-Open No. 2005-119031

Patent Document 3 discloses a printer in which a traveling ink jet recording head and a stationary ink container are connected and connected by an ink supply path with a damper.
Japanese Patent Application Laid-Open No. 07-070666

Japanese Patent Application Laid-Open No. H10-228707 provides compliance that allows ink in an ink cartridge to be supplied to a buffer tank partially sealed with an elastic film via an ink supply tube, and the recording head and the buffer tank can absorb ink pressure fluctuations. It is described that the water hammer is absorbed and attenuated by the tube in the connection flow path between the recording head and the buffer tank.
Japanese Patent Laid-Open No. 11-070666

In Patent Document 5, ink supplied from an ink tank through a flexible tube is allowed to flow into a first chamber of a damper chamber, and further from a passage hole as a throttle portion drilled in the bottom wall of the first chamber. The ink is supplied to the recording head from the ink outlet through the second chamber, and the upper surface of the first chamber is sealed with a flexible film to flexibly change the pressure fluctuation of the ink propagated from the tube side to the first chamber. Further, it is described that ink is absorbed by deformation of the photosensitive film and changes in the flow velocity of the ink are alleviated by a passage hole as a throttle portion, and ink is supplied to the recording head in a state where pressure fluctuation is sufficiently suppressed.
JP 2005-145051 A

Patent Document 6 describes that a pressure absorbing portion that absorbs pressure fluctuation is provided between a recording head and a main tank by a flexible film.
Japanese Patent Laid-Open No. 03-208665

In Patent Document 7, an ink jet recording head that receives ink from an ink cartridge via a filter, a cap member that seals the nozzle opening of the ink jet recording head, and negative pressure is supplied to the cap member via a damper tank. And a pump unit that reduces pulsation of negative pressure acting on the flow path through the recording head as much as possible by a damper tank to suppress the generation of bubbles due to liquid level fluctuations in the filter. ing.
JP-A-11-115212

Patent Document 8 is provided with an ink fluctuation suppressing device that absorbs an ink fluctuation amount inside a tube that is generated when the carriage is scanned on the carriage, and the volume of the ink fluctuation suppressing device changes depending on the amount of ink flowing in. It is described.
JP 2001-063082 A

  As described above, pressure fluctuation absorbing means using a flexible film is provided to absorb pressure fluctuation in the recording liquid supply path with respect to the recording head, but all of them are simple and reliable. However, there is a problem that pressure fluctuation cannot be suppressed.

  SUMMARY An advantage of some aspects of the invention is that it provides a liquid ejecting apparatus that can absorb pressure fluctuations with a simple configuration and an image forming apparatus including the liquid ejecting apparatus. Objective.

  In order to solve the above problems, a liquid discharge apparatus according to the present invention is a liquid discharge apparatus in which liquid is supplied via a liquid supply path from a liquid storage unit that stores liquid to a liquid discharge head that discharges droplets. The first flexible film member that relieves pressure fluctuation is provided in a part of the liquid supply path, and the first flexible film member that relieves pressure fluctuation is provided between the first flexible film member and the liquid discharge head. Buffer means including two flexible membrane members are provided, and at least one of the first and second flexible membrane members has a flexible membrane member on a surface opposite to the surface in contact with the liquid It was set as the structure by which the damping material which suppresses the vibration of this was apply | coated.

  Here, the first flexible membrane member is preferably provided in a plane orthogonal to the flow of the liquid flowing through the liquid supply path. The second flexible membrane member is preferably provided in a plane perpendicular to the liquid flow in the buffer means.

  Moreover, it is preferable that the buffer means has a configuration in which an air reservoir is provided between the second flexible membrane member and the buffer portion that reduces the pressure fluctuation of the liquid. Further, it is preferable that the buffer means is mounted on a moving carriage, and the second flexible film member is provided in a plane orthogonal to the moving direction of the carriage. In addition, a porous member is preferably provided between the buffer means and the liquid discharge head.

  A liquid discharge apparatus according to the present invention is a liquid discharge apparatus in which liquid is supplied via a liquid supply path from a liquid storage unit that stores liquid to a liquid discharge head that discharges droplets. Is provided with a flexible membrane member that reduces pressure fluctuations, and a damping material that suppresses vibration of the flexible membrane member is applied to the surface of the flexible membrane member opposite to the surface in contact with the liquid. It was set as the structure.

  The image forming apparatus according to the present invention includes the liquid ejection apparatus according to the present invention.

  According to the liquid ejection device of the present invention, the vibration damping material that suppresses vibration of the flexible film member is applied to the surface of the flexible film member opposite to the surface in contact with the liquid. The pressure fluctuation can be reliably suppressed with a simple configuration.

  According to the image forming apparatus according to the present invention, since the liquid ejection apparatus according to the present invention is provided, the pressure fluctuation in the liquid supply path can be reduced and the image quality can be improved.

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a perspective explanatory view of an ink jet recording apparatus as an image forming apparatus according to the present invention including a liquid ejection apparatus according to the present invention as viewed from the front side.
The ink jet recording apparatus includes an apparatus main body 1, a paper feed tray 2 for loading paper loaded in the apparatus main body 1, and a sheet on which an image is recorded (formed) by being detachably mounted on the apparatus main body 1. A paper discharge tray 3 for stocking is provided. Further, the one end side of the front surface of the apparatus main body 1 (the side of the paper supply / discharge tray portion) has a cartridge loading portion 4 for loading an ink cartridge as a first liquid storage means. The upper surface of 4 is an operation / display unit 5 provided with operation buttons and a display.

  The cartridge loading unit 4 contains a plurality of recording liquids (inks) that are different color materials, such as black (K) ink, cyan (C) ink, magenta (M) ink, and yellow (Y) ink. Ink cartridges (main tanks) 10k, 10c, 10m, 10y (referred to as “ink cartridge 10” when colors are not distinguished) as recording liquid cartridges as the first liquid storage means A front cover (cartridge cover) 6 that is opened when the ink cartridge 10 is attached or detached is provided on the front side of the cartridge loading portion 4 so as to be openable and closable.

Next, the mechanism part of the ink jet recording apparatus will be described with reference to FIGS. 2 is a schematic side view illustrating the outline of the mechanism, and FIG. 3 is an explanatory plan view of the main part.
A main guide rod 31 which is a main guide member horizontally mounted on the left and right side plates 21A and 21B constituting the frame 21 and a sub guide rod 32 hold the carriage 33 slidably in the main scanning direction, and a main scanning motor (not shown). Is moved and scanned in the direction indicated by the arrow in FIG. 3 (carriage main scanning direction) via the timing belt.

  As described above, the carriage 33 includes a recording head 34 including four droplet discharge heads that discharge ink droplets of yellow (Y), cyan (C), magenta (M), and black (Bk). A plurality of ink ejection openings are arranged in a direction crossing the main scanning direction (paper feeding direction), and the ink droplet ejection direction is mounted downward.

  As an inkjet head constituting the recording head 34, a piezoelectric actuator such as a piezoelectric element, a thermal actuator that uses a phase change caused by film boiling of a liquid using an electrothermal transducer such as a heating resistor, and a metal phase change caused by a temperature change. It is possible to use a shape memory alloy actuator to be used, an electrostatic actuator using an electrostatic force, or the like provided as pressure generating means for generating a pressure for discharging a droplet.

  The carriage 33 has a first pressure fluctuation mitigation device (means) via a supply tube 36 constituting a liquid supply path for supplying ink of each color from the ink cartridges 10 of each color mounted in the cartridge loading unit 4. 37 and a second pressure fluctuation mitigating device (means) 38 as a buffer means. The cartridge loading 4 is provided with a supply pump unit 24 which is a liquid feeding means for feeding ink in the ink cartridge 10 which is a liquid cartridge.

  On the other hand, as a paper feeding unit for feeding the papers 42 stacked on the paper stacking unit (pressure plate) 41 of the paper feeding tray 2, a half-moon roller (feeding) that separates and feeds the papers 42 one by one from the paper stacking unit 41. A separation pad 44 made of a material having a large friction coefficient is provided facing the paper roller 43) and the paper feed roller 43, and the separation pad 44 is urged toward the paper feed roller 43 side.

  In order to feed the paper 42 fed from the paper feeding unit to the lower side of the recording head 34, a guide member 45 for guiding the paper 42, a counter roller 46, a transport guide member 47, and a tip pressure roller. And a holding belt 48 which is a conveying means for electrostatically attracting the fed paper 42 and conveying it at a position facing the recording head 34.

  The transport belt 51 is an endless belt, and is configured to wrap around the transport roller 52 and the tension roller 53 and circulate in the belt transport direction (sub-scanning direction). Further, a charging roller 56 that is a charging unit for charging the surface of the transport belt 51 is provided. The charging roller 56 is disposed so as to come into contact with the surface layer of the transport belt 51 and to rotate following the rotation of the transport belt 51. Further, a guide member 57 is disposed on the back side of the conveyor belt 51 in correspondence with a printing area by the recording head 34.

  The transport belt 51 rotates in the belt transport direction of FIG. 3 when the transport roller 52 is rotationally driven through timing by a sub-scanning motor (not shown).

  Further, as a paper discharge unit for discharging the paper 42 recorded by the recording head 34, a separation claw 61 for separating the paper 42 from the conveying belt 51, a paper discharge roller 62, and a paper discharge roller 63 are provided. The paper discharge tray 3 is provided below the paper discharge roller 62.

  A duplex unit 71 is detachably mounted on the back surface of the apparatus body 1. The duplex unit 71 takes in the paper 42 returned by the reverse rotation of the conveyance belt 51, reverses it, and feeds it again between the counter roller 46 and the conveyance belt 51. The upper surface of the duplex unit 71 is a manual feed tray 72.

  Further, as shown in FIG. 3, a maintenance / recovery mechanism 81 including a recovery means for maintaining and recovering the state of the nozzles of the recording head 34 is arranged in the non-printing area on one side of the carriage 33 in the scanning direction. Yes. The maintenance / recovery mechanism 81 includes cap members (hereinafter referred to as “caps”) 82a to 82d (hereinafter referred to as “caps 82” when not distinguished from each other) for capping the nozzle surfaces of the recording head 34, and nozzle surfaces. A wiper blade 83 that is a blade member for wiping the ink, and an empty discharge receiver 84 that receives liquid droplets when performing empty discharge for discharging liquid droplets that do not contribute to recording in order to discharge the thickened recording liquid. ing. Here, the cap 82a is a suction and moisture retention cap, and the other caps 82b to 82d are moisture retention caps.

  Then, the waste liquid of the recording liquid generated by the maintenance / recovery operation by the maintenance / recovery mechanism 81, the ink discharged to the cap 82, the ink attached to the wiper blade 83 and removed by the wiper cleaner 85, and the idle ejection to the idle ejection receiver 94. The discharged ink is discharged and stored in a waste liquid tank (not shown).

  Further, as shown in FIG. 3, in the non-printing area on the other side in the scanning direction of the carriage 33, idle discharge is performed to discharge liquid droplets that do not contribute to recording in order to discharge the recording liquid thickened during recording or the like. An empty discharge receiver 88 for receiving the liquid droplets at the time is disposed, and the empty discharge receiver 88 is provided with an opening 89 along the nozzle row direction of the recording head 34.

  In the ink jet recording apparatus configured as described above, the sheets 42 are separated and fed one by one from the sheet feeding tray 2, and the sheet 42 fed substantially vertically upward is guided by the guide 45, and the transport belt 51 and the counter roller 46, and the leading end is guided by the conveying guide 37 and pressed against the conveying belt 51 by the tip pressing roller 49, and the conveying direction is changed by approximately 90 °.

  At this time, a charging voltage pattern in which a positive output and a negative output are alternately repeated from the AC bias supply unit of the control unit (not shown) to the charging roller 56, that is, an alternating voltage is applied and the conveying belt 51 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 paper 42 is fed onto the conveyance belt 51 charged alternately with plus and minus, the paper 42 is attracted to the conveyance belt 51, and the paper 42 is conveyed in the sub-scanning direction by the circular movement of the conveyance belt 51.

  Therefore, by driving the recording head 34 according to the image signal while moving the carriage 33, ink droplets are ejected onto the stopped paper 42 to record one line, and after the paper 42 is conveyed by a predetermined amount, Record the next line. Upon receiving a recording end signal or a signal that the trailing edge of the paper 42 has reached the recording area, the recording operation is finished and the paper 42 is discharged onto the paper discharge tray 3.

  Further, during printing (recording) standby, the carriage 33 is moved to the maintenance / recovery mechanism 81 side, and the recording head 34 is capped by the cap 82 to keep the nozzles in a wet state, thereby preventing ejection failure due to ink drying. . Further, the recording liquid is sucked from the nozzle by a suction pump (not shown) with the recording head 34 capped by the cap 82 (referred to as “nozzle suction” or “head suction”), and the thickened recording liquid and bubbles are discharged. Perform recovery action. In addition, an idle ejection operation for ejecting ink not related to recording is performed before the start of recording or during recording. As a result, the stable ejection performance of the recording head 34 is maintained.

  In this image forming apparatus, the liquid ejection apparatus according to the present invention includes a portion excluding a portion related to paper feeding and conveyance, that is, a recording head, a liquid supply device that supplies a recording liquid to the recording head, and a recording head. And a drive control unit (not shown) that drives

  Therefore, a liquid supply apparatus in the first embodiment of the liquid ejection apparatus according to the present invention will be described with reference to FIGS. 4 is a schematic explanatory view of the liquid supply apparatus of the embodiment, FIG. 5 is a perspective explanatory view of a first pressure fluctuation relaxation apparatus of the liquid supply apparatus, and FIG. 6 is a second pressure of the liquid supply apparatus. It is a perspective explanatory view of a fluctuation relaxation device.

  The liquid supply device includes a supply tube 36 from the ink cartridge 10, a first pressure fluctuation reducing device 37 to which an end of the supply tube 36 is connected, and a second pressure member directly connected to the first pressure fluctuation relaxation device 37. The liquid (recording liquid) is supplied to the recording head 34 attached to the second pressure fluctuation reducing device 38 via the pressure fluctuation reducing device 38.

  Here, as shown in FIG. 5, the first pressure fluctuation reducing device 37 includes a first connecting portion 101 that forms a substantially right-angled flow path 100 connected to the end of the supply tube 36, and the first connecting portion 101. A first connecting portion 101 and a hollow second connecting portion 102 connected to the second pressure fluctuation reducing device 38, and the first connecting portion 101 forms a part of the wall surface of the flow path 100. One flexible membrane member 103 is attached, and a damping material 104 is applied to the surface of the first flexible membrane member 103 opposite to the flow path 100.

  The first flexible membrane member 103 is formed of a film member such as polyethylene. For the vibration damping material 104, for example, a polymer vibration damping material such as silicone gel is used. The damping material 104 has a property of converting vibration energy into heat energy and reducing vibration of the solid surface.

  Here, the first flexible film member 103 is provided in a plane orthogonal to the flow of the recording liquid in the flow path 100 that bends at a substantially right angle. That is, the flexible film 103 </ b> A is in a plane orthogonal to the recording liquid flow in the arrow B direction in the flow path 100 in a plane orthogonal to the recording liquid flow in the arrow A direction. Each is provided with a flexible film 103B. These flexible films 103A and 103B are attached to the first connecting portion 101 by, for example, heat welding. Further, damping materials 104A and 104B are respectively applied to the surfaces of the flexible films 103A and 103B opposite to the surfaces in contact with the liquid.

  As shown in FIG. 6, the second pressure fluctuation reducing device 38 has a buffer case main body 111 forming the ink buffer portion 110 and a second connecting portion 102 of the first pressure fluctuation reducing device 37 connected to the upper end portion. And a hollow supply pipe 112 having a lower end facing the lower part in the buffer case main body 101, and a second surface forming a part of the wall surface of the buffer case main body 111 on the ceiling surface (upper surface) of the buffer case main body 111. A flexible membrane member 113 is attached, and a damping material 114 is applied to the surface of the second flexible membrane member 113 opposite to the inside of the buffer case main body 111.

  The second flexible membrane member 113 is formed of a film member such as polyethylene, for example. For the damping material 114, for example, a polymer damping material such as silicone gel is used. The vibration damping material 114 has a property of converting vibration energy into heat energy and reducing vibration of the solid surface.

  Here, in the second flexible membrane member 113, the recording liquid flowing into the buffer case main body 111 from the lower end of the supply pipe 112 generates a flow in the arrow C direction. Is provided in a plane orthogonal to the flow of the gas, and is attached to the buffer case main body 111 by, for example, heat welding.

  With this configuration, when pressure fluctuations occur in the liquid supply path, such as when the carriage 33 reciprocates, the first flexible film member 103 and the second pressure of the first pressure fluctuation reducing device 37 Pressure fluctuation is reduced by elastically deforming the second flexible membrane member 113 of the fluctuation mitigating device 38. Since the damping materials 104 and 114 are applied to the first flexible membrane member 103 and the second flexible membrane member 113, the first and second flexible membrane members 103 are applied. , 113 is converted into thermal energy to suppress surface vibration, so that the pressure fluctuation can be achieved with a higher damper effect than in the case of the first and second flexible membrane members 103, 113 alone. Can be suppressed.

Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 7 is a schematic explanatory view of a second pressure fluctuation reducing device in the same embodiment.
Here, an air reservoir 117 is formed in the upper part of the ink buffer unit 110 configured in the buffer case main body 111 of the second pressure fluctuation reducing device 38. The air reservoir 117 is intentionally formed at the time of initial ink filling.

  Thus, the ink flow due to the pressure fluctuation generated in the supply tube 36 can be more effectively relaxed by the air reservoir 117 having a compressible property together with the first pressure fluctuation mitigating device 37. Become.

Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 8 is a schematic perspective explanatory view of the second pressure fluctuation reducing device in the same embodiment.
Here, the second flexible membrane member 113 is attached to the buffer case main body 111 of the second pressure fluctuation mitigating device 38 in a plane orthogonal to the direction of reciprocating movement of the carriage 33 (arrow D direction), for example, by heat welding or the like. The vibration damping material 114 is applied to the surface opposite to the surface in contact with the liquid.

  Since the pressure fluctuation generated in the ink buffer unit 110 configured in the buffer case main body 111 is generated substantially in parallel with the direction of the reciprocating movement of the carriage 33, vibration suppression is performed in a plane orthogonal to the direction of the pressure fluctuation. By attaching the second flexible film member 114 having the material 114 applied to the outer surface, the generated pressure fluctuation can be reduced.

Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 9 is a schematic explanatory view of a second pressure fluctuation relaxation device in the same embodiment.
In the buffer case main body 111 of the second pressure fluctuation reducing device 38, the porous body 120 is attached to the recording head 34 by, for example, thermal welding. The porous body 120 is made of a member such as SUS, but is not limited thereto.

  As described above, the pressure fluctuation generated in the supply tube 36 and the pressure fluctuation generated in the ink buffer unit 110 are prevented from propagating to the recording head 34 side through the porous body 120 having high fluid resistance, and the recording head 34 side. Foreign matter can be prevented from entering.

  The image forming apparatus according to the present invention is not limited to a printer having a single function configuration, and may be an image forming apparatus having a composite function such as printer / facsimile / copying. Further, the liquid is not limited to ink.

FIG. 3 is an explanatory perspective view seen from the front side of the ink jet recording apparatus as the image forming apparatus according to the present invention including the liquid supply apparatus according to the present invention. It is a side schematic block diagram explaining the whole structure of the mechanism part of the apparatus. It is principal part plane explanatory drawing of the mechanism part. It is typical explanatory drawing with which it uses for description of 1st Embodiment of this invention. It is a typical perspective explanatory view of the 1st pressure fluctuation mitigation device similarly. It is a typical perspective explanatory view of the 2nd pressure fluctuation mitigation device similarly. It is typical explanatory drawing with which it uses for description of 2nd Embodiment of this invention. It is typical explanatory drawing with which it uses for description of 3rd Embodiment of this invention. It is typical explanatory drawing with which it uses for description of 4th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Apparatus main body 2 ... Paper feed tray 3 ... Paper discharge tray 4 ... Cartridge loading part 10k, 10c, 10m, 10y ... Ink cartridge 33 ... Carriage 34 ... Recording head 36 ... Supply tube 37 ... 1st pressure fluctuation relaxation device 38 DESCRIPTION OF SYMBOLS 2nd pressure fluctuation relaxation apparatus 51 ... Conveyance belt 101 ... 1st connection part 102 ... 2nd connection part 103 ... 1st flexible film member 104 ... Damping material 110 ... Ink buffer part 111 ... Buffer case main body 112 ... Supply pipe 113 ... Second flexible membrane member 114 ... Damping material 117 ... Air reservoir 120 ... Porous body

Claims (8)

In a liquid ejection apparatus in which the liquid is supplied via a liquid supply path from a liquid storage unit that stores liquid to a liquid discharge head that discharges droplets.
A first flexible membrane member for reducing pressure fluctuation is provided in a part of the liquid supply path;
Between the first flexible membrane member and the liquid discharge head, buffer means including a second flexible membrane member that relieves pressure fluctuation is provided,
At least one of the first and second flexible membrane members is coated with a damping material that suppresses vibration of the flexible membrane member on the surface opposite to the surface in contact with the liquid. A liquid discharge apparatus characterized by that.   The liquid ejection apparatus according to claim 1, wherein the first flexible film member is provided in a plane orthogonal to the flow of the liquid flowing through the liquid supply path. apparatus.   3. The liquid ejection apparatus according to claim 1, wherein the second flexible film member is provided in a plane orthogonal to the liquid flow in the buffer means. Discharge device.   4. The liquid ejection apparatus according to claim 1, wherein the buffer means is provided with an air reservoir between the second flexible film member and a buffer portion that reduces pressure fluctuations of the liquid. A liquid discharge apparatus characterized by comprising:   5. The liquid ejection apparatus according to claim 1, wherein the buffer means is mounted on a moving carriage, and the second flexible film member is provided in a plane orthogonal to the moving direction of the carriage. A liquid discharge apparatus characterized by comprising:   6. The liquid ejection apparatus according to claim 1, wherein a porous member is provided between the buffer means and the liquid ejection head. In a liquid ejection apparatus in which the liquid is supplied via a liquid supply path from a liquid storage unit that stores liquid to a liquid discharge head that discharges droplets.
A flexible membrane member that alleviates pressure fluctuations is provided in a part of the liquid supply path, and the flexible membrane member is provided on a surface opposite to the surface in contact with the liquid. A liquid ejection device, characterized in that a damping material that suppresses vibration of the liquid is applied.   8. An image forming apparatus for forming an image by discharging liquid from a liquid discharge head of a liquid discharge apparatus, wherein the liquid discharge apparatus is the liquid discharge apparatus according to claim 1. apparatus.

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