JP2007268766A - Inkjet printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make small a piping space necessary in the periphery of a relay tank by adding improvements to the constitution of the relay tank in an inkjet printer equipped with the relay tank, and thereby to achieve the miniaturization of the whole inkjet printer. <P>SOLUTION: A resin film with a flexibility is formed in a bag shape and an opening side is sealed by a sealing member 52a, whereby a sub tank 52 is constituted. An introduction pipe part 52c and a supply pipe part 52d are integrally formed with the sealing member 52a. The introduction pipe part 52c and the supply pipe part 52d linked with a supply conduit 51 and a flexible conduit 53 are arranged side by side on one side of the sub tank 52. Thus the piping space necessary in the periphery of the sub tank 52 can be made small, enabling the inkjet printer A to be made compact. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ink jet printer in which a relay tank is provided on an ink supply path connecting a print head and an ink cartridge.

  2. Description of the Related Art Conventionally, an ink jet printer having a relay tank formed by forming a flexible film in a bag is known. As such an ink jet printer, for example, as disclosed in Patent Document 1, there is a separation ink supply method in which ink is once pumped from an ink cartridge to a relay tank and then supplied to the print head via the relay tank. It has been adopted. With such a configuration, not only can the ink be reliably supplied to the print head regardless of the characteristics such as the film forming property of the ink, but also the layout of a relatively large ink cartridge can be freely set. In addition to being able to reduce the size, the ink cartridge can be replaced even during printing.

  Further, the relay tank is formed of a flexible bag-like film, and the ink from the ink cartridge is temporarily stored therein, so that the pressurized ink in the ink cartridge is stored in the relay tank. Even if a pressure fluctuation occurs, the fluctuation can be absorbed by deformation of the relay tank, thereby preventing the pressure fluctuation from being transmitted directly to the print head.

Here, in the relay tank, an introduction pipe for introducing ink from the ink cartridge is connected to the lower side, and a supply pipe for supplying ink to the print head is connected to the side.
JP-A-10-109426

  By the way, in the separated ink supply type ink jet printer having the above-described relay tank, in order to perform color printing, not only a plurality of color ink cartridges but also a plurality of relay tanks corresponding to each color are necessary. become. As a result, the number of pipes connecting the ink cartridge and the relay tank and the pipes connecting the relay tank and the print head increase accordingly, so that a lot of piping space is required around the relay tank, and the overall size of the inkjet printer is reduced. There is a possibility of inhibiting the conversion.

  The present invention has been made in view of such a point, and an object of the present invention is to improve the configuration of the relay tank in the inkjet printer including the relay tank as described above by improving the configuration of the relay tank. The purpose is to reduce the size of the entire inkjet printer by reducing the piping space required around it.

  In order to achieve the above object, according to the present invention, an introduction pipe and a supply pipe connected to the relay tank are provided side by side on the relay tank, thereby reducing the space for piping.

  Specifically, according to the first aspect of the present invention, the flexibility is provided on the ink supply path that connects the ink cartridge in which the ink is stored and the print head that performs printing by discharging ink onto the print medium. The present invention is intended for an ink jet printer provided with a relay tank formed by forming a film having a film on a bag.

  The relay tank is provided with an introduction pipe for introducing ink from the ink cartridge and a supply pipe for supplying ink to the print head side by side on the relay tank. Shall.

  With the above configuration, since the introduction pipe and the supply pipe connected to the relay tank are provided side by side on the relay tank, compared to the conventional configuration in which the introduction pipe and the supply pipe are respectively connected to different sides of the relay tank, It is possible to reduce the space for the piping, and thereby the entire inkjet printer can be reduced in size. That is, in the conventional configuration in which the introduction pipe and the supply pipe are connected to different sides of the relay tank, a space for piping is required on each side, so that a large space is required for arranging the relay tank. However, as described above, by arranging and connecting on one side of the tank, it is only necessary to provide a space for piping on the one side, thereby saving space around the relay tank.

  Here, as described above, when the introduction pipe and the supply pipe are connected side by side on one side of the relay tank, the two pipes are close to each other, so that a predetermined amount of ink is accumulated in the relay tank. Ink may flow from the introduction pipe to the supply pipe as a shortcut. Then, the function of the relay tank as a pressure damper that absorbs ink pressure fluctuation on the ink cartridge side is lost, and the pressure fluctuation is directly transmitted to the print head. In particular, the smaller the relay tank, the higher the rigidity of the bag constituting the tank and the difficulty of swelling, so that the function as a pressure damper becomes difficult.

  Therefore, the relay tank is provided with expansion promoting means for promoting the expansion of the tank by flowing the introduced ink toward the side opposite to the one side where the introduction pipe and the supply pipe are connected. Is preferable (Invention of Claim 2). In this way, it is possible to prevent the ink from flowing in the tank as a shortcut and from flowing out directly from the introduction pipe to the supply pipe. Therefore, the ink is surely expanded by flowing the ink through the entire relay tank. be able to.

  In the relay tank, the expansion promoting means is preferably a projecting portion extending inward from the position between the introduction pipe and the supply pipe on the one side. ).

  As a result, the ink flowing into the relay tank through the introduction pipe flows through the flow path formed in the tank by the protruding portion toward the side opposite to the side where the introduction pipe and the supply pipe are connected. After that, the ink reaches the opening of the supply pipe, and the ink spreads throughout the interior of the relay tank. By doing so, it is possible to reliably prevent the ink from flowing as a shortcut in the relay tank, and to reliably prevent the pressure fluctuation on the ink cartridge side from being directly transmitted to the print head.

  The expansion promoting means may be a tubular projecting portion that communicates with the opening of either the introduction pipe or the supply pipe and extends toward the inside of the tank in the relay tank. invention).

  In this way, the ink flows into the tank from the tip of the tubular projecting portion that opens into the relay tank, or flows from the inside of the relay tank to the outside of the tank through the tubular projecting portion. As a result, the ink flow can be made to spread, and the ink can be surely prevented from flowing through the relay tank as a shortcut.

  As described above, according to the ink jet printer of the present invention, since the introduction pipe and the supply pipe are arranged and connected to one side of the relay tank, the space for the piping can be reduced, and the entire ink jet printer Can be miniaturized.

  In addition, in the above-described configuration, since the expansion promoting means for promoting the expansion of the relay tank by ink is provided, it is possible to reliably prevent the ink from being short-circuited and flowing in the tank due to insufficient expansion of the relay tank. Thus, the function as a pressure damper of the relay tank can be ensured.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. It should be noted that the following description of the preferred embodiment is merely illustrative in nature and is not intended to limit the present invention, its application, or its use.

-Overall configuration-
1 to 6 show an inkjet printer A according to an embodiment of the present invention. The printer A is used in a photographic print system. For example, an image transmitted via a communication cable from a reception block (not shown) that acquires image data and order information and performs necessary correction processing and the like. Data is configured to be printed on a print paper P (print medium) based on the order information.

  As shown in FIGS. 1 to 6, the printer A includes a paper storage section 1 provided at the lower part of the apparatus for storing a roll-shaped print paper P, and a print paper drawn from the paper storage section 1. The printing unit 2 provided at the upper part of the apparatus so as to record and print image data on P, and the ink supplied to the printing unit 2 are stored on the side of the apparatus (on the left and right sides in FIG. 3). Ink storage units 3 and 3 are provided. Further, on the upper side of the printer A, on the downstream side in the transport direction of the printing unit 2, the back side printing unit 4 for printing the reference number and the like on the back side of the print paper P, and the printed print paper P are discharged. A discharge roller 46 for performing printing and a tray 5 for receiving the discharged print paper P are provided. Although only shown in FIG. 6, the printer A is covered with a cover 6 except for the tray 5.

  The paper storage unit 1 is located almost directly below the print unit 2 and stores a long print paper P wound in a roll shape while being held by a core roller 21 as shown in FIG. Is configured to do. Here, the paper container 1 is closed by a door member 12 that forms part of the cover 6 that covers the entire printer A and that can be opened and closed laterally. By doing so, the print paper P held in the magazine 11 can be replaced. In this embodiment, there is only one type of print paper P stored in the magazine storage unit 1, but the present invention is not limited to this, and it may be configured to store two or more types of print paper P.

  The printing unit 2 includes a print head H that forms an image (that is, performs printing) by ejecting ink onto the print paper P. The print head H is configured to be movable along a guide 21 extending in the main scanning direction, and has two head units 38 and 38 arranged in the sub-scanning direction. A predetermined image, characters, or the like can be printed on the print paper P by ejecting ink from nozzles (not shown) provided on the print paper P.

  The ink reservoirs 3 and 3 include box-shaped cartridge cases 61 and 61 disposed on the left and right sides of the printer A, respectively, and inks having different hues are sealed in the cases 61 and 61. Are detachably accommodated (in this embodiment, as shown in FIG. 3, three ink cartridges are accommodated on the left side and four on the right side as viewed from the paper discharge side. Have been). Therefore, by removing these ink cartridges 62, 62,... From the cartridge cases 61, 61, the used or used ones can be replaced with new ones. These ink cartridges 62, 62,... Are respectively yellow (Y), magenta (M), cyan (C), black (K), red (R), violet (V), and clear (CL: (Transparent) ink is enclosed.

  Further, the ink supplied from the ink cartridges 62, 62,... Is temporarily stored at a height position between the ink storage unit 3 and the print unit 2 on the left side when viewed from the discharge side of the printer A. Sub tanks 52, 52,... These sub tanks 52, 52,... Are connected to the print head H of the print unit 2, and the ink in the sub tanks 52, 52,... Is discharged by the negative pressure when ink is ejected from the nozzles of the print head H. Is supplied to the print head H.

-Paper transport mechanism-
As shown in FIG. 6, the printer A is provided with a paper transport mechanism that pulls out the print paper P from the paper storage unit 1 and transports it along a predetermined transport path. This paper transport mechanism includes a supply unit U1, a print unit U2, a cutter unit U3, and a discharge unit U4 in order from the paper container 1 so as to form the transport path, and is positioned on the transport path of the print unit U2. The image data is printed on the print paper P to be printed. In this embodiment, in addition to supplying the print paper P from the magazine accommodating unit 1, the manual feed unit U5 configured to be able to supply print paper of a predetermined size from the manual feed tray 81 is also provided. In the following embodiment, a case where the print paper P is supplied mainly from the magazine accommodating unit 1 will be described.

  When the paper transport mechanism prints on the roll-shaped print paper P, the print paper P set in the paper storage unit 1 is pulled out of the paper storage unit 1 by the supply unit U1 and positioned in the print unit 2. Then, image data is printed by the print head H while the supplied print paper P is conveyed by the print unit U2, and then the printed print paper P is conveyed to the cutter unit U3. After cutting to a predetermined print size by the cutter unit U3, the curling of the paper P is removed by the discharge unit U4 and the paper is sent to the tray 5. In the following description, the transport upstream side and the downstream side when the print paper P is transported during the printing are also simply referred to as the upstream side and the downstream side, respectively.

  More specifically, the supply unit U1 includes a core roller 21 for storing the print paper P in a roll shape in the paper storage unit 1, and the print paper P drawn from the core roller 21. A guide roller 22 for positioning in the width direction and an arrangement for closing the opening for conveying the print paper P between the paper container 1 and the print unit 2 in order to keep the paper container 1 airtight. A closing roller 23 provided, a conveyance driving roller 24 that is rotationally driven by an electric motor (not shown) so as to convey the print paper P, and pressure-bonding rollers 25, 25 arranged opposite to the conveyance driving roller 24. Yes. In the present embodiment, the guide roller 22 is provided, but a guide may be provided instead.

  That is, the supply unit U1 is configured to pull out the print paper P from the paper storage unit 1 and convey it to the print unit 2 side by rotating the conveyance drive roller 24. The closing roller 23 is made of, for example, a sponge material, and has a role as a sealing member for ensuring airtightness in the paper storage unit 1. By providing the closing roller 23, When the humidifying device 13 for preventing surface cracks due to drying of the printed paper P is installed in the paper accommodating portion 1, the inside of the magazine accommodating portion 1 is efficiently humidified by the humidifying device 13. Yes.

  The transport driving roller 24 is rotated in the forward direction in which the print paper P is pulled out from the magazine storage unit 1 and transported to the print unit 2 side by an electric motor (not shown), and the reverse of returning the print paper P into the magazine storage unit 1. The rotation of the direction can be switched. Thus, after the printed portion of the paper P is cut into a predetermined size by the cutter unit U3 on the downstream side in the transport direction with respect to the transport driving roller 24, the long print paper P is returned to the upstream side to start from the top of the paper. When printing is performed or when paper is supplied from the manual feed unit U5 instead of the long print paper P, the long print paper P can be returned into the paper storage unit 1.

  As shown in FIGS. 1 and 2, the print unit U2 includes a guide rail 30 that guides the print head H in the main scanning direction X (a direction perpendicular to the conveyance direction (sub-scanning direction Y) of the print paper P); Printing can be performed by a print belt H that is wound around two pulleys and that reciprocates the print head H along the guide rail 28, an electric motor 32 that rotates the pulley, and the print head H. A paper holding part D (see FIG. 3) that holds the ink by suction at a proper position, and a pressure-sensitive print transport roller 33 disposed on the downstream side of the paper holding part D are provided. Here, the main scanning direction X corresponds to the width direction of the print paper P, and the sub-scanning direction Y corresponds to the longitudinal direction of the print paper P.

  As shown in FIGS. 2 and 6, the paper holding portion D includes a guide plate 34 having a suction hole 34a opened on the surface (upper surface), and a print supplied onto the guide plate 34 by the supply unit U1. A fan 35 is provided as a suction means for sucking and holding the paper P on the surface of the guide plate 34 by sucking the paper P through the suction hole 34a. The guide plate 34 is formed of a plate-like member, and a housing 36 that forms a space with the guide plate 34 is disposed on the back surface (lower surface) side of the guide plate 34, and the fan 35 is disposed in this space. Is arranged. The suction hole 34a penetrates in the thickness direction of the guide plate 34 and communicates with the space. A negative pressure is generated on the surface side of the guide plate 34 through the suction hole 34a by the operation of the fan 35. Thus, the printed paper P is attracted and held on the surface of the guide plate 34.

  The guide plate 34 has a flushing portion 37 for receiving a small amount of ink ejected from nozzles (not shown) of the print head H in order to prevent the ink from thickening during printing, and printing when printing is not performed. A cap portion (not shown) is provided at a standby position of the head H and configured to suck ink from the nozzles of the print head H to prevent thickening of the ink.

  The flushing portion 37 includes an opening 37a formed in the guide plate 34, and a casing (not shown) that forms a space communicating with the opening below the guide plate 34. The casing communicates with a waste liquid tank 7 provided at the lower part on the discharge side of the printer A, and is configured so that air inside the casing can be sucked by the fan 35. Further, a sponge-like ink absorbing material 37b capable of absorbing ink is disposed in the opening 37a, and the ink soaked into the ink absorbing material 37b is also stored in the space. As a result, the ink ejected toward the opening 37 a of the flushing portion 37 is sucked into the housing and guided to the waste liquid tank 7.

  Although not particularly illustrated, the cap portion has a space in which a negative pressure is formed, and a small amount of ink is sucked from the nozzles of the print head H into the space. Thereby, it is possible to prevent the ink from being thickened by the nozzle and becoming difficult to discharge. Here, the space of the cap part is designed to have a negative pressure inside by using a pump as an air pressurizing part 56 of an ink supply system described later.

  The guide plate 34 is further formed with a plurality of substantially rectangular border holes 34b at predetermined intervals in the width direction of the paper P. Specifically, the edge hole 34b is formed at a position where a part of the edge hole 34b is exposed at both ends in the width direction of the paper P when the paper P is placed on the guide plate 21. A plurality of sheets are provided according to the paper size (for example, A4, B5, etc.).

  In this way, even when part of the ink ejected from the print head H to the edge in the width direction of the paper P protrudes from the paper P when performing borderless printing on the paper P, the ink protrudes from the paper P. The ink is discharged from the edge hole 34b, and it is possible to prevent the ink from adhering to the surface of the guide plate 34 and soiling the surface of the plate 34.

  As shown in FIG. 4, the print head H has head units 38, 38,... Provided with a large number of ink discharge nozzles on the bottom surface (surface facing the guide plate 34) in two stages in the sub-scanning direction. They are arranged side by side (the head unit 38 does not have to be two stages, and may be one stage or three stages or more).

  Each of the head units 38 has the same configuration, and each of the head units 38 is composed of seven nozzle arrays arranged in the main scanning direction X and ejecting the inks of the colors. In each nozzle array, ink discharge nozzles are arranged in a row in the sub-scanning direction Y. Accordingly, each head unit 38 is configured to be able to form a color image by itself. At each step of paper conveyance, the print head H is scanned in the main scanning direction X. At this time, at each position in the main scanning direction X, each head unit 38 applies ink from a predetermined ink ejection nozzle of each color. Discharge at the same time. Here, the ink discharge nozzle in the present embodiment is of a general piezo type that discharges ink by changing the volume of the pressure chamber filled with ink by a piezo element.

  The cutter unit U3 includes a rotary blade 41, and moves the print blade P to a predetermined size by moving the rotary blade 41 in the width direction at a predetermined position in the transport direction of the print paper P while rotating the rotary blade 41. It is configured as follows. The cutter unit U3 is provided on the downstream side of the rotary blade 4 with respect to the conveyance, and includes a post-cutting conveyance roller 42 for sending out the cut paper P. After the cutting, the paper P is transported to the back surface printing unit 4 on the downstream side by the rotation of the transport roller 42.

  Further, below the cutter unit U3, a cutter waste collection box 70 for collecting chips of the paper P after cutting is disposed. The cutter waste collection box 70 is configured to be slidable along the paper P discharge direction (right direction in FIG. 6) and detachable from the apparatus main body, so that the user can easily discard the cutter waste. .

  A handle 71 is attached to the front side (right side in FIG. 6) of the cutter waste collection box 70. And the near side of the cutter waste collection box 70 is formed of a transparent plastic material so that the accommodation state of the chips can be visually confirmed.

  The discharge unit U4 is provided on the downstream side of the back surface printing unit 4 for printing a serial number or the like on the back surface of the print paper P, and conveys the print paper P and curls the print paper P. It has a decurling part 45 comprising a plurality of pressure-bonding type discharge rollers 46, 46,. The decurling portion 45 is configured such that the pressure rollers 46, 46,... And the guides 47, 48 are arranged on the opposite side of the curl attached to the printed paper P so that the paper P is bent and convex. The print paper P can be curled, and the paper P having almost no curl can be discharged onto the tray 5.

  As described above, the printer A is provided with a manual feed unit U5 for supplying the paper P manually by the user, in addition to the paper P wound in a roll shape. A tray 81 provided on the upstream side in the transport direction of the upper part of the apparatus and a transport roller 82 located on the downstream side in the transport direction. The paper P on the manual tray 81 is fed by the manual guide 83 by the rotation of the transport roller 82. Are conveyed so as to be sandwiched between the conveyance driving roller 24 and the pair of pressure-bonding rollers 25, 25.

  Here, since the paper P conveyed from the manual feed tray 81 is not curled, when the paper P is sent to the decurling unit 45 of the discharge unit U4, the curl is attached. Therefore, a determination unit (not shown) is provided for determining whether the paper P is supplied from the manual feed tray 81 or supplied from the paper storage unit 1, and the transport path of the paper P is determined based on the determination result. It is preferable to control to switch. For example, the paper P supplied from the manual feed tray 81 may be controlled to be discharged to the discharge tray 5 without passing through the decurling unit 45.

-Ink supply system-
As shown in FIG. 7, the ink supply system of the printer A transfers the ink in the ink cartridge 62 of the ink reservoir 3 located on both the left and right sides of the printer A to the sub tank 52 via the electromagnetic valve 50 and the supply conduit 51. The ink in the sub tank 52 is supplied to the print head H through the flexible pipe 53. Specifically, the ink cartridge 62 to the sub tank 52 are sent out by pressurized air supplied by an air pressurizing unit 56 described later, while the nozzles of the print head H are supplied from the sub tank 52 to the print head H. When the ink is ejected from the nozzle, it flows due to the negative pressure generated in the pressure chamber (not shown) of the nozzle by the piezo element (until the ink is ejected, the sub tank 52 is filled with a specified amount and expanded. The supply pressure to the nozzles is maintained at a predetermined pressure by the pressure of the pressure and is supplied to the print head H). The sub tank 52 is attached to the print head H at a predetermined height so that ink is supplied to the print head H at an appropriate pressure.

  By configuring the ink supply system as described above, the ink in the ink cartridge 62 is temporarily stored in the sub tank 52 and supplied from the sub tank 52 to the print head H. Therefore, printing is not interrupted. The ink cartridge 62 can be replaced. In addition, since the sub tank 52 also serves as a pressure damper, it is possible to prevent the ink pressure fluctuation generated in the ink cartridge 62 from being directly transmitted to the print head H. It is possible to prevent ink leakage or the like from being caused by a large pressure. Although only one ink supply system is shown in FIG. 7, in reality, seven ink supply systems are formed corresponding to seven types of inks having different hues.

  The ink cartridge 62 is configured by storing an ink tank 62T formed in a bag shape using a flexible material in a resin case. The ink cartridge 62 further includes an air pressurizing unit 56 that supplies pressurized air to the inside of the case via an air supply path 55, and a pressure regulating valve 57 that adjusts the air pressure supplied to the inside of the case. ing. In such a configuration, a predetermined amount of ink can be supplied from the ink tank 62T into the supply conduit 51 by setting the inside of the case to a predetermined pressure.

  The sub-tank 52 is also formed in a bag shape (bag) using a flexible material such as a resin sheet. As will be described in detail later, the inner space of the sub-tank 52 has two tank chambers 52b and 52b. It is divided into (relay tanks), and the two tanks are connected together. The tank chambers 52b and 52b are provided with an introduction pipe part 52c (introduction pipe) and a supply pipe part 52d (supply pipe) connected to the supply pipe line 51 and the flexible pipe line 53, respectively. As a result, the two tank chambers 52b and 52b can temporarily store inks having different hues.

  The sub tank 52 is erected in a substantially box-shaped storage section 54 provided on the left side when viewed from the carry-out side of the inkjet printer A (in FIG. 7, a storage section for arranging one sub tank 52 is schematically illustrated. The sub-tank sensor that outputs a detection signal in the vicinity of the sub-tank 52 (above the side surface of the sub-tank 52 in this embodiment) according to the deformation amount in the thickness direction of the two tank chambers 52b, 52b of the sub-tank 52. S and S are arranged.

  Here, the storage portion 54 has two plate members 54 a that extend in the vertical direction on one surface of the sub-tank 52 and are supported at the lower end portion so as to be swingable in the thickness direction of the sub-tank 52. , 54a. The plate members 54a and 54a are arranged so as to correspond to the belly portions (portions that expand most in the thickness direction) of the tank chambers 52b and 52b of the sub tank 52. In addition, on both walls in the longitudinal direction of the tank of the storage portion 54, an introduction pipe portion 52c and a supply pipe provided to communicate with the tank chambers 52b, 52b of the sub tank 52 in a state where the sub tank 52 is stored. A cutout is formed so as to avoid the protruding portion of the portion 52d.

  The sub tank sensors S, S are arranged so as to come into contact with the upper portions of the plate members 54a, 54a arranged corresponding to the belly portions (portions that expand most in the thickness direction) of the tank chambers 52b, 52b of the sub tank 52. When the side surface of the sub tank 52 is displaced in the thickness direction of the tank as the tank chambers 52b and 52b expand or contract, the tilting of the plate members 54a and 54a corresponding to the displacement is detected. It has become.

  Specifically, when the remaining amount of ink in the tank chambers 52b, 52b of the sub tank 52 becomes a predetermined amount (for example, 9 ml) or less, the tank sensors S, S are disposed so as to be in a non-contact state with the plate member. ing. Therefore, in this case, the electromagnetic valve 50 is operated to be in an open state so that the ink remaining amount becomes an appropriate amount (the specified amount, for example, 10 ml), and the ink is placed in the tank chambers 52b and 52b of the sub tank 52. Supply. On the other hand, when the tank chambers 52b, 52b of the sub tank 52 are filled with an appropriate amount of ink, the tank sensors S, S are configured to contact the plate member. Activates the electromagnetic valve 50 to close it, and stops the supply of ink to the tank chambers 52b, 52b of the sub tank 52.

  The ink reservoir 3 is provided with a detachable sensor 58 that determines whether or not the ink cartridge 62 is present in the ink reservoir 3.

-Sub tank-
Hereinafter, the structure of the sub tank 52 will be described in detail.

  As described above, the sub tank 52 is formed in a bag shape using a flexible material such as a resin sheet, and is configured to repeatedly expand and contract in the thickness direction depending on the amount of ink filled therein. ing. Specifically, the sub-tank 52 is formed in a cylindrical shape by welding the upper and lower sides of two resin sheets, for example, and then has a substantially central portion in the cylinder axis direction so as to divide the internal space into two. It is obtained by welding and positioning resin sealing members 52a and 52a, in which two pipe portions 52c and 52d are integrally formed in openings at both ends in the cylinder axis direction, and welding them to a sheet. One sub tank Two tank chambers 52b and 52b are formed in 52 (see FIG. 7).

  Then, by providing the sealing members 52a and 52a as described above, inks having different hues are temporarily stored in the tank chambers 52b and 52b or supplied to the print head H, respectively. Therefore, the installation space can be reduced as compared with the conventional sub tank. Moreover, since the ink tanks for two colors can be attached in one operation, the attachment operation can be reduced as compared with the case where the sub tanks for one color are respectively attached.

  Further, by integrally forming the introduction pipe portion 52c and the supply pipe portion 52d as the inflow / outlet of ink into the tank chambers 52b and 52b with the sealing member 52a, the two pipe portions 52c and 52d are connected to the tank chamber 52b. The pipes 52c and 52d connected to the pipe portions 52c and 52d can be arranged in one side, so that the arrangement of the sub tank 52 can be performed. The space for can be saved. Thereby, size reduction of the whole apparatus can be achieved.

  However, as described above, when the two tank chambers 52b and 52b are formed by dividing the interior of the sub tank 52, the maximum deformation amount in the thickness direction of the resin sheet is smaller than when one tank chamber is formed, Even if ink is supplied, it may not swell sufficiently.

  Then, for example, in order to eliminate the air in the ink supply system, the ink chambers 52b and 52b are temporarily evacuated and then the ink is supplied into the tank chambers 52b and 52b in the vacuum state at the initial operation of the apparatus for supplying ink. Even if ink is supplied from 62, 62, the sub tank 52 does not sufficiently swell due to the supplied ink, and when printing is started in this state, the ink flows directly to the print head H side. In this case, the ink pressure fluctuation is directly transmitted to the print head H without functioning as a pressure damper, which may cause problems such as ink leakage.

  Further, not only at the time of initial start-up but also in the operation state such as during printing, the sub tank 52 is repeatedly expanded and contracted by the inflow and outflow of ink, so the sub tank 52 must be sufficiently expanded by the ink. For example, the ink does not reach the entire tank chambers 52b and 52b, but moves only in the vicinity of the entrance / exit of the tank chamber 52b, losing the function as a pressure damper, and excessive ink supply pressure is transferred to the print head H side. I will tell you.

  Therefore, as a characteristic part of the present invention, as shown in FIG. 8, a plate-like protrusion 52e is provided in the tank chambers 52b and 52b, and a flow path through which ink flows in the entire tank chambers 52b and 52b. (Arrow in the figure) was formed. FIG. 8 shows only one tank chamber 52b.

  Specifically, in the sealing member 52a for sealing the tank chamber 52b, a plate-like protruding portion 52e extending inwardly from the intermediate position between the introduction pipe portion 52c and the supply pipe portion 52d is integrated. Formed. The protrusion 52e extends in the tank chamber 52b to a position where a flow path is formed on the side opposite to the side sealed by the sealing member 52a (the tank chamber back side). Yes.

  As a result, the ink that has flowed into the tank chamber 52b through the introduction pipe portion 52c of the sealing member 52a is guided to the back side of the tank chamber 52b by the protruding portion 52e, and the sealing member 52a is passed from the back side. Is folded back to the sealing side and flows from the supply pipe portion 52d to the print head H side. Accordingly, the ink that has flowed in can reach the entire inside of the tank chamber 52b without being short-circuited in the tank chamber 52b and flow toward the supply pipe portion 52d, so that the sub-tank 52 can be sufficiently expanded, and functions as a pressure damper. Can be secured.

  Further, with the above-described configuration, the ink that has flowed in through the introduction pipe portion 52c can flow through the entire tank chamber 52b, so that old ink can be prevented from stagnating in the tank chamber 52b. be able to.

  The protruding portion 52e may be rod-shaped or may be a separate member from the sealing member 52a. Further, as shown in FIG. 9, a tubular projecting portion 52f formed in a tubular shape may be provided so as to communicate with the opening of the inlet tube portion 52c on the ink inflow side. If such a tubular projecting portion 52f is provided, the ink can be more reliably fed to the inner side of the tank chamber 52b. Therefore, the ink that has flowed in is short-cut in the tank chamber 52b, and the supply pipe portion 52d. The sub-tank 52 can be expanded more reliably.

  Here, in the sub tank 52 ′ having only one tank chamber, when the introduction pipe portion 52c and the supply pipe portion 52d are provided side by side only on one side of the sub tank 52 ′ as described above, the pipe portions 52c, 52d Since the other side that is not provided is configured only by a sheet having low rigidity, it may be easily turned or bent, and the expansion of the sub tank 52 ′ due to ink filling may be hindered.

  Therefore, as shown in FIG. 10, an adhesive region 91 made of double-sided tape or adhesive is provided on the wall surface of the storage portion 54 for storing the sub tank 52 ′, and the tube portion of the sub tank 52 ′ is provided in the adhesive region 91. What is necessary is just to adhere and fix the other side in which 52c and 52d are not provided. By doing so, it is possible to reliably prevent the other side of the sub-tank 52 'from being turned or bent. In the case where the adhesive region 91 is constituted by a double-sided tape, it is preferable to use a double-sided tape having a thickness of about 2 mm in consideration of the shape of the sub tank 52 '.

  Further, as shown in FIG. 11, the storage portion 54 is provided with a bulging wall portion 92 that bulges in the thickness direction of the sub tank 52 ′, and a slit hole 93 extending in the vertical direction is formed in the bulging wall portion 92. Then, the other side of the sub tank 52 ′ may be inserted into the slit hole 93. By so doing, the other side of the sub-tank 52 ′ is held in the slit hole 93, so that it is possible to more reliably prevent the other side from being turned or bent.

  Further, as shown in FIG. 12, a clip 94 having two plate members is provided on the wall surface of the storage portion 54, and the other side of the sub tank 52 ′ is interposed between the two plate members of the clip 94. May be inserted.

  As described above, according to the present embodiment, in the sub tanks 52, 52,... Provided on the ink supply path between the ink cartridges 62, 62,. 52c and the supply pipe 52d are arranged side by side on one side, so that the piping space of the supply pipe 51 and the flexible pipe 53 connected to the introduction pipe 52c and the supply pipe 52d can be reduced. Miniaturization can be achieved.

  Further, a plate that forms a flow path in which the ink that has flowed into the tank chamber 52b is supplied to the print head H side in the tank chamber 52b formed inside the sub-tanks 52, 52,. Since the protruding portion 52e is provided, the ink is distributed throughout the tank chamber 52b, and the sub tanks 52, 52,. In other words, with the above-described configuration, the ink supplied from the ink cartridges 62, 62,... Is temporarily stored in the sub tank 52 and sufficiently expands the sub tank 52. As a result, the ink supply pressure on the ink cartridges 62, 62,... Can be prevented from being directly transmitted to the print head H side. Ink leakage can be prevented.

(Other embodiments)
The configuration of the present invention is not limited to the above embodiment, but includes various other configurations. That is, in the above embodiment, a part of the sub tank 52 is welded to form the two tank chambers 52b and 52b. However, the present invention is not limited to this, and only one tank chamber is formed in the sub tank 52. Alternatively, three or more tank chambers may be formed.

  In the above-described embodiment, the protrusions 52e and 52f are provided so that the ink flows to the back side of the tank chamber 52b. However, the present invention is not limited to this. For example, the protrusion length of the protrusions 52e and 52f The length may flow at least through the central portion of the tank chamber 52b. That is, the protrusions 52e and 52f may have such a length that the front end portion is positioned on the deeper side of the tank chamber than the central portion of the tank chamber 52b. As described above, since the tank sensor S is attached to the most inflated portion of the tank chamber 52b, at least the central portion of the tank chamber 52b needs to be sufficiently inflated in order to operate the sensor S normally. Because.

  Furthermore, in the above-described embodiment, the tubular projecting portion 52f formed in a tubular shape is provided so as to communicate with the opening of the introduction tube portion 52c on the ink inflow side, but this is not limiting, and the supply tube portion 52d on the ink outflow side is provided. It may be provided so as to communicate with the opening. In this way, since the ink can be supplied from the back side of the tank chamber 52b to the print head H side, it is possible to spread the ink throughout the tank chamber 52b without stagnation of the ink in the tank chamber 52b. .

  As described above, the ink jet printer according to the present invention has the sub-tank provided on the ink supply path between the ink cartridge and the print head by arranging the introduction pipe part 52c and the supply pipe part 52d side by side. Since the size of the printer can be reduced, it is particularly useful for an ink jet printer for color printing including a plurality of subtanks, for example.

1 is a perspective view showing an ink jet printer according to an embodiment of the present invention. It is a top view of an inkjet printer. It is a front view of an inkjet printer. It is a left view of an inkjet printer. It is a rear view of an inkjet printer. FIG. 3 is a schematic diagram illustrating a transport path of print paper. It is a schematic diagram of an ink supply system. It is sectional drawing in the thickness direction approximate center position of the subtank in which the protrusion part was provided in the tank chamber. It is sectional drawing in the thickness direction approximate center position of the subtank in which the tubular protrusion part was provided in the tank chamber. It is a perspective view which shows a mode that a subtank is adhere | attached and fixed to the adhesion | attachment area | region provided on the wall surface of the accommodating part. It is a perspective view which shows a mode that the other side of a sub tank is inserted in the slit hole provided in the bulging wall part of the accommodating part. It is a perspective view which shows a mode that the other side of a sub tank is clamped with the clip provided on the wall surface of the accommodating part.

Explanation of symbols

A Inkjet printer P Print paper (print medium)
H Print head 50 Solenoid valve 51 Supply line (ink supply path)
52 Sub tank (relay tank)
52a Sealing member 52b Tank chamber 52c Introduction pipe part (introduction pipe)
52d Supply pipe section (supply pipe)
52e protrusion 52f protrusion (tubular protrusion)
53 Flexible pipe (ink supply path)
62 Ink cartridge 62T Ink tank

Claims (4)

A relay formed by forming a flexible film on a bag body on an ink supply path that connects an ink cartridge in which ink is stored and a print head that performs printing by discharging ink onto a print medium. An ink jet printer provided with a tank,
The relay tank is provided with an introduction pipe for introducing ink from the ink cartridge and a supply pipe for supplying ink to the print head arranged side by side on the relay tank. Inkjet printer featuring. In claim 1,
The relay tank includes expansion promoting means for promoting expansion of the tank by flowing the introduced ink toward a side opposite to the one side to which the introduction pipe and the supply pipe are connected. Inkjet printer. In claim 2,
The ink jet printer according to claim 1, wherein the expansion accelerating means is a projecting portion extending inward from the position between the introduction pipe and the supply pipe on the one side in the relay tank. In claim 2,
The ink jet printer according to claim 1, wherein the expansion accelerating means is a tubular projecting portion that communicates with an opening of either the introduction pipe or the supply pipe in the relay tank and extends toward the inside of the tank.

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