JP4539819B2 - Inkjet printer - Google Patents

Description

  The present invention relates to an inkjet printer, and more particularly to a structure of an inkjet printer that supplies ink from an ink tank to a recording head mounted on a moving carriage via a flexible tube (ink supply tube). is there.

  2. Description of the Related Art Conventionally, a tube supply type ink jet printer that supplies ink to a recording head mounted on a moving carriage from an ink tank fixed in the ink jet printer main body through a flexible tube is disclosed in Patent Document 1 and Patents. It is known from Document 2 etc.

  In the configuration of Patent Document 1, an ink flow path to each nozzle and a common ink chamber (damper) are provided so as to have an opening surface on one side surface in the vertical direction of a recording head in which a plurality of nozzle rows are arranged vertically. Chamber) and the common ink chamber is connected to all the ink flow paths, while ink is supplied from an ink tank fixed in the printer body to the common ink chamber through a flexible tube. Supplied. Then, the opening surface in the common ink chamber is sealed with a flexible film (vibration absorbing film).

  By fixing a vibrating body made of a piezoelectric element at a predetermined position of the ink flow path, facing a longitudinal side surface (a surface having an opening surface) of the recording head, and driving the vibrating body, the ink flow Pressure is applied to the ink in the path, and the ink is ejected from the nozzle toward the paper.

  In the configuration of Patent Document 2, a piezo element is fixed to both sides of the front and back in the vertical direction of a recording head in which a plurality of nozzle rows and ink flow paths are arranged vertically, and the piezo element is applied by voltage application. In this configuration, the ink is ejected from the nozzle by the bending that occurs, and a damper member (damper) that introduces ink from an ink tank at a fixed position through a flexible tube and supplies the ink to the ink flow path of the recording head. Chamber) on the carriage. In this damper member, a filter is sandwiched between the first member having one side surface opened in the vertical direction and the second member having both side surfaces opened in the vertical direction, and one side of the second member (the filter The outer surface facing the holding surface in parallel is sealed with a flexible film. An ink inflow port communicating with a flexible tube having one end connected to an ink tank at a fixed position is provided below the first member, and an ink flow path of the recording head is provided below the second member. Providing a connecting ink outlet is disclosed.

In any of these prior arts, as the carriage reciprocates, an inertial force acts on the ink in the tube connecting the ink tank and the recording head, particularly at the time of return, and the ink pressure in the direction of the recording head (nozzle) is increased. Inadvertent fluctuations are absorbed by the deformation of the flexible film (film) of the damper, and the ink discharge pressure from the nozzles is kept uniform.
JP 63-17056 A (refer to FIGS. 1 to 5) Japanese Examined Patent Publication No. 7-121583 (see FIG. 2, FIG. 3, etc.)

  However, according to the configurations of Patent Documents 1 and 2, the damper chamber is a vertical type, and one surface is sealed with a flexible film in the vertical direction. When arranging the recording heads in a plurality of rows, when the damper chambers for ink of each color are arranged in parallel, the damper chambers have an appropriate gap between adjacent damper chambers because the flexible film is displaced. For this reason, there is a problem in that the case on the carriage has to be arranged, the apparatus on the carriage is increased in size, the number of parts is increased, and the cost is increased.

  In order to solve this problem, it is conceivable to arrange a plurality of damper chambers side by side and accumulate them in one case. In that case, the plurality of damper chambers sufficient to absorb the pressure fluctuation of the ink may be considered. If an area on one side (sealing surface of the flexible membrane) is to be secured, the area on one side of the case increases, and in this case as well, an increase in the size of the device on the carriage cannot be avoided.

  The present invention has been made in view of the above-described conventional problems, and an object of the present invention is to provide an ink jet printer capable of making a damper means such as a damper chamber mounted together with a recording head at a low manufacturing cost and compact. To do.

In order to achieve the above object, an ink jet printer according to a first aspect of the present invention includes an ink jet recording head mounted on a carriage that moves with respect to a recording medium, and an ink supply pipe that extends from an ink tank mounted on the main body. In the ink jet printer configured to supply ink to the recording head via a damper device mounted on the carriage, the recording head has three or more ink supply channels, and the damper device Has a plurality of damper chambers partitioned to correspond to the plurality of ink supply channels, and each damper chamber has an ink inlet port from the ink supply pipe and an ink outlet port to the ink supply channel. with each pair one damper chamber of the plurality of damper chambers to the other plurality of damper chambers Are disposed back to back form through the primary partition wall Te,
Each of the one damper chamber and the plurality of damper chambers has a flexible film facing the main partition wall, and the main partition wall is disposed along a horizontal direction, The one damper chamber is configured to overlap all of the plurality of damper chambers when viewed from a vertical direction perpendicular to the partition wall, and the one damper chamber is further below the main partition wall. The plurality of damper chambers are disposed on the upper side of the main partition wall .

According to a second aspect of the present invention, in the ink jet printer according to the first aspect, the damper device is disposed above the recording head so that the one damper chamber faces the recording head. Are arranged .

According to a third aspect of the present invention, in the ink jet printer according to the first or second aspect, the outlet of the one damper chamber is provided in the main partition wall, and similarly, the plurality of damper chambers. The outlet is provided in the main partition wall .

According to a fourth aspect of the present invention, in the ink jet printer according to any one of the first to third aspects, a liquid having the highest use frequency flows among the liquids flowing through the plurality of ink supply channels. One ink supply channel, and a plurality of second ink supply channels through which a liquid having a lower use frequency than the first ink supply channel flows,
The first ink supply channel communicates with the one damper chamber, and the plurality of second ink supply channels communicate with the plurality of damper chambers .

According to a fifth aspect of the present invention, in the inkjet printer according to the fourth aspect, the first ink supply channel flows black ink, and the plurality of second ink supply channels flow color inks other than black. is there.

The invention according to claim 6 is the ink jet printer according to any one of claims 1 to 5 , wherein each of the damper chambers communicates with an exhaust passage to an exhaust valve for discharging bubbles to the atmosphere. The exhaust passage is formed integrally with a main body case forming a damper device, and the exhaust valve is integrated with the damper device .

According to a seventh aspect of the present invention, in the ink jet printer according to the sixth aspect, the main body case includes: a box-shaped lower case whose upper and lower surfaces are opened; and an upper case disposed on the upper surface side of the lower case. An exhaust valve box portion in which the exhaust valve is housed, and damper box portions constituting a plurality of damper chambers are formed integrally with the lower case, and a damper lid portion covering the upper surface side of the damper box portion; An exhaust passage communicating from the damper box portion to the exhaust valve box portion is formed integrally with the upper case .

According to a seventh aspect of the present invention, in the ink jet printer according to the sixth aspect, the main body case includes: a box-shaped lower case whose upper and lower surfaces are opened; and an upper case disposed on the upper surface side of the lower case. An exhaust valve box portion in which the exhaust valve is housed, and damper box portions constituting a plurality of damper chambers are formed integrally with the lower case, and a damper lid portion covering the upper surface side of the damper box portion; An exhaust passage communicating from the damper box portion to the exhaust valve box portion is formed integrally with the upper case.

According to an eighth aspect of the present invention, in the ink jet printer according to the seventh aspect, the upper and lower cases are liquid-tightly coupled to each other at their mating surfaces.

A ninth aspect of the invention is the ink jet printer according to the seventh aspect of the invention, wherein the damper cover portion and the exhaust passage are sealed with a flexible film on the open surface of the upper case facing the mating surface. It is stopped and is an open surface of the lower case facing the mating surface, and the damper box portion is sealed with a flexible film.

According to a tenth aspect of the present invention, in the ink jet printer according to the seventh aspect , in the upper case or the lower case, an ink flow path communicating from each ink supply pipe to each damper chamber is formed in a recessed manner. The open surface in the flow path is sealed with a flexible film or film material.

According to an eleventh aspect of the present invention, in the ink jet printer according to any one of the eighth to tenth aspects, the sealing surfaces of the flexible films and the film material are planes parallel to the mating surfaces.

According to a twelfth aspect of the present invention, in the ink jet printer according to the seventh aspect, the recording head is supported in a state facing the recording medium, and communicates with the exhaust holder and a head holder that houses the damper device. And an exhaust valve box housing the exhaust valve, wherein the ink outlet of the damper device and the ink supply port of the recording head are disposed opposite to each other, and a seal member is interposed therebetween, and the exhaust The valve box portion is fixed to the head holder in a direction in which the ink outlet and the ink supply port face each other.

According to a thirteenth aspect of the present invention, in the ink jet printer according to the twelfth aspect , the fixing portion between the exhaust valve box portion and the head holder includes a pin and a hole that fit in a direction in which the ink supply port faces. It consists of

The invention according to claim 14 is the ink jet printer according to claim 13 , wherein the passage in the exhaust valve box portion opens in parallel with a direction in which the ink outlet and the ink supply port face each other. The pin and the hole are provided in the mounting arm portion protruding from the side surface of the exhaust valve box portion and the mounting arm portion of the head holder facing the mounting arm portion.

  As described in detail above, according to the invention described in claim 1, by arranging the plurality of damper chambers back to back via the main partition wall, the plurality of damper chambers can be combined, and the damper device The whole can be made compact.

According to the invention described in claim 1, the surfaces facing the main partition wall of the plurality of damper chambers arranged back to back via the main partition wall are sealed with a flexible film. The open area of each damper chamber can be formed large to set a large area where the flexible film can bend due to pressure fluctuations of the ink, and the damper operation can be sufficiently performed while making the entire damper device compact.

According to the first aspect of the present invention, since the one damper chamber is configured to overlap all of the plurality of damper chambers when viewed from the vertical direction orthogonal to the main partition wall, The damper chamber can be arranged compactly.

Further, according to the invention described in claim 1, manufacturing cost because a plurality of damper chambers having an open face in the same direction can seal at one flexible membrane, the sealing work becomes extremely easy Can also be reduced.

As in the fifth aspect of the present invention, by providing a plurality of ink supply channels and damper chambers for each ink color, a damper effect can be obtained for each ink for multicolor recording.
As in the invention described in claim 6, by connecting each damper chamber to the exhaust passage to the exhaust valve for discharging the bubbles to the atmosphere, the bubbles are separated from the ink flowing into the damper chamber. Less ink can be supplied to the recording head. Further, as in the invention described in claim 6, if an exhaust passage is formed in the main body case having a plurality of damper chambers and the exhaust valve means is also integrated into the main body case, a structure for removing bubbles or the like during maintenance is provided. Can be mounted on the carriage, and the structure can be made compact. In particular, if the exhaust passage is recessed so as to open in the same direction as the opening surface of the damper chamber, the damper chamber, the exhaust passage, and the like can be obtained by sticking one flexible film to the surface of the main body case. Can be formed at the same time, and the manufacturing cost can be reduced.

According to the seventh aspect of the present invention, the damper device is a combined body of upper and lower cases, and the exhaust valve box portion in which the exhaust valve is accommodated and the damper box portions constituting a plurality of damper chambers are the lower portion. A damper lid portion that is integrally formed with the case and covers the upper surface side of the damper box portion, and an exhaust passage that communicates from the damper box portion to the exhaust valve box portion are integrally formed with the upper case. Therefore, it is possible to finish a predetermined flow path shape only by combining those in which recesses such as complicated ink passages are previously formed in each case.

According to the invention described in claim 8, since the upper and lower cases are liquid-tightly coupled to each other at their mating surfaces, the sealing material is costly at the joint and the liquid-tightness is improved.

According to the ninth aspect of the present invention, the damper lid portion and the exhaust passage which are the open surfaces of the upper case facing the mating surfaces are sealed with a flexible film, and are opposed to the mating surfaces. Since the damper box is an open surface of the lower case and is sealed with a flexible film, the flexible film is easily sealed after the upper and lower cases are joined. It can be carried out.

According to a tenth aspect of the present invention, the upper case or the lower case is formed with a recessed ink channel that communicates from each ink supply pipe to each damper chamber, and the open surface of each ink channel is flexible. Since it is sealed with a conductive film or a film material, the selection and formation of the ink flow path with respect to the case can be extremely easily performed.

According to invention of Claim 11, since the sealing surface of each said flexible film | membrane and film material is a plane parallel to the said mating surface, the sticking operation | work with respect to a flexible film | membrane and a film material case is carried out. It becomes easy.

According to the twelfth aspect of the present invention, the recording head is supported in a state of facing the recording medium, and the head holder that accommodates the damper device, and the exhaust that communicates with the exhaust passage and accommodates the exhaust valve. A valve box part, and an ink outlet port of the damper device and an ink supply port of the recording head are arranged to face each other, and a seal member is interposed between the two, and the exhaust valve box part is attached to the head holder. Since the ink outlet and the ink supply port are fixed in a direction opposite to each other, the recording head supported by the head holder and the damper device housed in the head holder can be fixed only by fixing them. The direction and the sealing direction coincide with each other, and the reliability of the liquid-tight action by the sealing member can be improved.

According to a thirteenth aspect of the present invention, the fixing portion between the exhaust valve box portion and the head holder includes a pin and a hole that are fitted in a direction in which the ink supply port faces, and the pin is The direction of fitting into the mounting hole matches the direction in which the ink connection port, which is the ink outlet, and the ink supply port face each other. Therefore, the reliability of the liquid-tight action of the seal member can be achieved by fixing the pin and the mounting hole. Can be improved. Further, by crimping with heat, the fixing operation can be performed easily and quickly as compared with the case of screw tightening, and it is impossible to detach, so that there is no rattling of internal parts and the reliability of the recording head unit is improved.

According to the fourteenth aspect of the present invention, the passage in the exhaust valve box portion opens in parallel with the direction in which the ink outlet and the ink supply port face each other, and is formed on the side surface of the exhaust valve box portion. Since the protruding mounting arm portion and the mounting arm portion of the head holder facing the mounting arm portion are provided with the pin and the hole, it is possible to increase the strength of each mounting arm portion and strengthen the fixing. it can. Further, even if the exhaust valve box is pushed in parallel with the fixing direction with the head holder during maintenance, the exhaust valve box is not easily deformed, and there is an effect that the exhaust operation can be performed reliably.

  Next, an embodiment embodying the present invention will be described. As shown in FIG. 1, the ink jet printer includes a recording mechanism unit 2 that is included in a main body frame 1 and ejects ink onto a sheet P that is a recording medium, and maintenance of the recording head unit 3 in the recording mechanism unit 2. A maintenance unit 4 that performs processing, and ink tanks 5a to 5d that store ink to be supplied to the recording head unit 3 that is fixedly disposed in the main body frame 1 are configured.

  A plurality of ink tanks 5 for full-color recording (reference numerals 5a to 5d are assigned to ink tanks for individual colors, that is, black, cyan, magenta, and yellow, see FIG. 1). Can be exchanged accordingly.

  In the recording mechanism unit 2, a carriage 9 is slidably mounted on a left and right rear guide shaft 6 and a front guide shaft 7 provided in parallel in the main body frame 1, and the recording head unit is mounted on the carriage 9. 3 is integrally attached.

  A carriage drive motor 10 disposed on the right rear side of the main body frame 1 and a timing belt 11 which is an endless belt are configured so that the carriage 9 can reciprocate in the left and right directions along the front and rear guide shafts 6 and 7. Yes. On the other hand, although not shown, the paper P is transported horizontally (in the direction of arrow A in FIG. 1) in a direction perpendicular to the moving direction of the carriage 9 on the lower surface side of the recording head unit 3 by a known paper transport mechanism. .

  Outside the width of the sheet P to be conveyed, an ink receiving portion 12 is provided on one end side (the left end portion in FIG. 1 in the embodiment), and a maintenance unit 4 is disposed on the other end side. Yes. As a result, the recording head unit 3 periodically discharges ink to prevent nozzle clogging at the flushing position where the ink receiving portion 12 is provided, and receives ink at the ink receiving portion 12 during the recording operation. . At the head standby position on the other end side, the maintenance unit 4 is arranged to clean the nozzle surface, and to perform a recovery process for selectively sucking ink for each color and bubbles (in the damper device 13 described later) Remove the air).

  As shown in FIG. 1, the ink tank 5 for each individual color can be inserted and mounted from the front at a position below the nozzle surface on the lower surface of the recording head unit 3. In FIG. 1, in order from the left, an ink tank 5a for black ink (BK), an ink tank 5b for cyan ink (C), an ink tank 5c for magenta ink (M), and an ink tank for yellow ink (Y). 5d is arranged horizontally and in parallel.

  On the rear side of each ink tank mounting portion, a hollow needle for ink supply (not shown) protrudes horizontally so as to face the insertion direction (rear side wall surface) of each color ink tank 5. The proximal end portion of the hollow needle corresponding to each color ink is connected to the recording head unit 3 via the corresponding flexible ink supply tubes 14a to 14d. In this case, the middle portions of the black and cyan ink supply tubes 14a and 14b and the middle portions of the magenta and yellow ink supply tubes 14c and 14d are stacked one above the other.

  Next, a first embodiment of the recording head unit 3 mounted on the carriage 9 will be described with reference to FIGS. In the present embodiment, the recording head unit 3 is fixed to the lower surface side of the box-shaped head holder 20 and the bottom plate 20a of the head holder 20 for full color recording as shown in FIGS. An ink jet recording head 21, a damper device 13 and an exhaust valve means 26 fixed to the upper side of the bottom plate 20 a are provided.

  On the lower surface of the recording head 21, a row of black ink (BK) nozzles 22a, a row of cyan ink (C) nozzles 22b, and a yellow ink are shown from the left side in FIG. The row of nozzles 22c for ink (Y) and the row of nozzles 22d for magenta ink (M) are formed long in a direction perpendicular to the moving direction (main scanning direction) of the carriage 9. Each nozzle 22 is exposed downward so as to face the upper surface of the paper P.

  The recording head 21 has an ink supply port for each ink color (for example, four colors) on one side of the upper surface, similar to those known in JP-A-2002-67312, JP-A-2001-219560, and the like. Ink is distributed to a number of pressure chambers via ink supply channels extending from the supply port, and ink is ejected from the nozzles 22 by driving actuators 23 such as piezoelectric elements corresponding to the pressure chambers. . A flexible flat cable 24 for applying a voltage to the actuator 23 is fixed to the upper surface of the actuator 23. Ink is supplied to each ink supply port from each ink tank 5 via a damper device 13.

  Next, based on FIGS. 3-11, the structure of the damper apparatus 13 and the exhaust valve means 26 is explained in full detail. The damper device 13 includes a plurality of independent damper chambers 27 for each ink color, which are partitioned by sub-partition walls 35a and 30 that sandwich the main partition wall 35 and intersect the main partition wall. In the embodiment, a part of a black ink (BK) damper chamber 27a is disposed under the main partition wall 35, and a cyan ink (C) damper chamber 27b and a yellow ink (Y ) Damper chamber 27c and magenta ink (M) damper chamber 27d are partitioned and arranged by sub-partition walls 35a and 30, and are configured in two layers vertically.

  Specifically, the main body case 25 in the damper device 13 has a rectangular cylindrical side wall as an outer periphery, and a box-shaped lower case 32 whose upper and lower surfaces are opened, and an upper surface of the lower case 32 is arranged and fixed. The upper case 31 is formed. Both the upper case 31 and the lower case 32 are injection-molded with a synthetic resin material and are liquid-tightly coupled by ultrasonic welding or the like.

  The lower case 32 is integrally formed with a damper box portion constituting a plurality of damper chambers 27 and a storage portion 34 as an exhaust valve box in which an exhaust valve (valve element) 57 and the like are stored, as will be described later. ing. The lower case 32 is provided with an opening on the lower surface thereof that opens most of the area of the lower surface, and a main partition wall 35 is formed at a position spaced in parallel from the opening and the upper open surface. Has been. The opening is sealed with a damper flexible film (synthetic resin film that is impermeable to air and liquid) 36. Specifically, the outer peripheral edge of the flexible film 36 is bonded to the lower end surface of the outer peripheral wall 37 that defines the outer periphery of the opening by bonding or ultrasonic welding. Between the flexible film 36 and the main partition wall 35, a first chamber 27a-1 of a damper chamber for black ink (BK) is formed. A gap for deformation of the flexible film 36 is secured between the flexible film 36 and the bottom plate 20 a of the head holder 20, and the damper device 13 is fixed to the head holder 20.

  On the upper surface of the main partition wall 35, a sub-partition wall 35a that rises integrally with the main partition wall 35 is formed, and a portion above the main partition wall 35 in the lower case 32 is described later. A plurality of damper chambers are formed in cooperation with the upper case 31. In the embodiment, two sub-partition walls 35a are spaced apart from each other, and together with the side wall of the lower case 32, 3 for cyan ink (C), yellow ink (Y), and magenta ink (M) are used. Individual damper chambers 27b to 27d (specifically, second chambers 39b to 39d of the damper chamber) are formed. As shown in FIG. 6, each of the sub partition walls 35 a is formed extending over the entire length of the lower case 32, and the damper chambers 27 b to 27 d (specifically, the second chambers 39 b to 39 b) at positions away from the upper surface of the main partition wall 35. 39d) communicates with the ink outlets 41b to 41d for each ink color.

  Further, an additional sub partition wall 35 b is formed extending to a position off the upper surface of the main partition wall 35 in the vicinity of the ink outlets 41 b to 41 d, and between the sub partition wall 35 b and the side wall of the lower case 32, black A second chamber 39a of a damper chamber for ink (BK) is formed. The lower end of the second chamber 39a communicates with the ink outlet 41a (see FIGS. 3 and 6).

  The first chamber 27a-1 of the damper chamber for black ink (BK) passes through the passage 42 as a constricted portion penetrating the second chamber 39a in the vertical direction through the cylindrical portion formed along the sub partition wall 35b. It is communicating (refer FIG.5, FIG.6, FIG.8 (c)). The passage 42 is formed to have a cross-sectional area smaller than that of the first chamber 27a-1, and the flow path resistance is set to be larger than that in the first chamber 27a-1.

  The upper case 31 is formed in a flat shape having a plurality of recesses on the upper surface. The upper case 31 includes a damper lid portion that covers the upper surface side of the damper box portion (the plurality of damper chambers 27a to 27d) and a portion that extends from the damper lid portion so as to cover the upper surface side of the storage portion 34. They are integrally formed (see FIGS. 8A to 8C).

  In the present embodiment, on the upper surface side of the upper case 31, cyan separated by two sub-partition walls 30 at an upper position substantially corresponding to the first chamber 27a-1 of the damper chamber for black ink (BK). First chambers 27b-1 to 27d-1 of three damper chambers 27b to 27d for ink (C), yellow ink (Y), and magenta ink (M) are formed to open upward (FIG. 4). The sub partition wall 30 is located on the extended surface of the sub partition wall 35a of the lower case 32, and a plurality of passage holes 44 as throttle portions are formed in the bottom wall 29 of the first chambers 27b-1 to 27d-1. The first chambers 27 b-1 to 27 d-1 are formed so as to penetrate vertically, and the first chambers 27 b-1 to 27 d-1 individually communicate with the lower chamber (the chamber partitioned by the sub-partition wall 35 a in the lower case 32), that is, the second chambers 39 b-39 d. is doing.

  The passage hole 44 is formed to have a smaller cross-sectional area than each of the first chambers 27b-1 to 27d-1, and the flow path resistance is set larger than that of each of the first chambers 27b-1 to 27d-1.

  The upper open surface of the first chambers 27b-1 to 27d-1 and the upper open surface of the exhaust passage 51 for each ink color, which will be described later, are made of a single flexible film for damper (made of synthetic resin, air and liquid Non-permeable film) 43 is commonly sealed. Specifically, the flexible film 43 is bonded to the outer peripheral wall defining the outer periphery of each first chamber and the upper end surface of the sub partition wall 30 by adhesion or ultrasonic welding. The first chambers 27b-1 to 27d-1 serve as a damper lid portion of the upper case 31.

  As shown in FIG. 5, the ink outlets 41 a to 41 d are arranged side by side on the lower surface of the lower case 32, and are opened downward at positions extending downward from the flexible film 36. On the other hand, the recording head 21 has a plurality of ink supply ports (not shown) communicating with the end portions of the ink supply channels (manifolds) for the respective ink colors on the upper surface at positions facing the respective ink outlets 41a to 41d. ing. Each of the ink outlets 41a to 41d passes through an opening provided in the bottom plate 20a of the head holder 20, and communicates with each ink supply port of the recording head 21 via a sealing material such as rubber packing.

  As shown in FIGS. 3 and 4, an ink inlet 47 for each ink color (four in the embodiment) is provided in a portion 32a protruding in a flange shape from the side surface of the lower case 32 opposite to the ink outlets 41a to 41d. Ink inlets for black ink (BK), cyan ink (C), yellow ink (Y), and magenta ink (M) are indicated by 47a, 47b, 47c, and 47d, respectively, and are opened upward. ing.

  A joint member 45 having an ink flow path for each ink color is connected to these ink inflow ports via a seal 46 such as a packing in correspondence with the lower end of each ink flow path. The top ends of the ink supply tubes 14 a to 14 d for the respective ink colors are connected to the upper ends of the ink flow paths of the joint member 45.

  The ink inlet 47a for the black ink (BK) is connected to the first chamber of the corresponding damper chamber 27a via a concave passage 48 formed horizontally downward in the lower surface of the lower case 32. ing. The other ink inlets 47b to 47d are formed in a vertical direction (with respect to the surface formed by the main partition wall 35) along the concave passage 48 formed horizontally downward and on the lower surface of the lower case 32 and the one side wall of the lower case 32. It is connected to corresponding first chambers of damper chambers 27b to 27d via a communication passage 49 formed so as to extend in a substantially orthogonal direction and a communication passage 50 penetrating vertically through the upper case 31 (FIG. 4, FIG. 5, FIG. 7 (a), FIG. 7 (b) and FIG. 8 (b)). In that case, since the opening surface of the communication path 50 is at a height close to the lower surface of the flexible film 43, the ink flowing into the damper chambers 27 b to 27 d faces the opening surface of the communication path 50. Since it is possible to directly collide with the approaching flexible film 43, it is possible to efficiently absorb (damp) ink pressure fluctuations in the ink supply tubes 14b to 14d.

  The open lower surfaces of the ink inflow ports 47a to 47d and the concave passage 48 are sealed with portions where the flexible film 36 is extended.

  A U-shaped rib 35c in plan view with both ends connected to the side wall on the concave passage 48 side is flexible on the ceiling surface of the first chamber 27a-1 of the damper chamber for black ink (BK), that is, the lower surface of the main partition wall 35. The height of the conductive film 36 is not reached. For this reason, the space surrounded by the U-shaped rib 35c is provided with a space in which ink does not enter, and the pressure variation of the ink described later is absorbed together with the air and the flexible film 36 therein. Yes.

  In addition, third chambers 55a to 55d of the damper chambers are formed in the upper surface of the upper case 31 so as to be independent of each other at positions corresponding to the second chambers 39a to 39d in the vicinity of the ink outlets 41a to 41d. (See FIGS. 4 and 7B). Each of the third chambers 55a to 55d communicates with the corresponding second chamber 39a to 39d through an air hole 54 formed through the upper case 31. That is, the damper chambers 27a to 27d for each ink color are each composed of three chambers from the first chamber to the third chamber.

  Further, the upper case 31 is formed with an exhaust hole 53 communicating with the upper part of each of the second chambers 39a to 39d between the first chamber and the third chamber. The upper ends of the exhaust holes 53 are respectively connected to a plurality of exhaust passages 51 that are recessed in the upper surface of the upper case 31 independently of each other, and the exhaust passages extend in the longitudinal direction of the main body case (the ink inflow ports 47a to 47d). The other end is connected to connection ports 52a, 52b, 52c, and 52d that extend in a direction orthogonal to the direction of connecting the ink outlets 41a to 41d and communicate with a plurality of exhaust valve means 26 described later (see FIG. 4).

  Each exhaust hole 53 is formed in a cylindrical wall that hangs down from the upper case 31 into each of the second chambers 39a to 39d, and opens into each of the second chambers 39a to 39d at a predetermined distance from the upper case 31. ing. That is, as will be described later, even when the air bubbles in the second chambers 39a to 39d are exhausted from the exhaust hole 53, air of only the suspended height of the cylindrical wall is secured above the second chambers 39a to 39d. Yes.

  The third chambers 55a to 55d and the exhaust passages 51 of the respective damper chambers are covered with open portions of the flexible film 43, and the respective chambers and passages are defined.

  The damper device 13 is fixed on the carriage 9 so that the main partition wall 35 and the flexible films 36 and 43 extend in parallel with the moving direction of the carriage 9, that is, in parallel with the nozzle opening surface of the recording head 21. .

  Next, the exhaust valve means 26 will be described. On one side of the lower case 32 (the right end in FIGS. 4 and 8A) having a damper box portion in which a plurality of damper chambers are formed, the exhaust valve means 26 is provided. An exhaust valve box that forms an outer case, that is, a storage portion 34 is integrally formed. As shown in FIG. 8, the storage portion 34 and the lower case 32 are connected at the upper portion, with a space between them, and the side wall of the head holder 20 is inserted into the space. In the storage portion 34, four passage holes 56 that are long in the vertical direction and open in the vertical direction are formed for each ink color. Each of the passage holes 56 includes an upper half large-diameter portion 56a and a lower half small-diameter passage 56b. A small-diameter valve rod 58 is integrally formed at the lower end of the large-diameter valve body 57. A packing 59 such as an O-ring for sealing is disposed on the valve rod 57 and fitted on the valve rod 58. A packing 59 and a valve body 57 are inserted into the large diameter portion 56a so as to be movable up and down, and a valve rod 58 is inserted into the small diameter passage 56b. The lower end of the valve rod 58 extends to the vicinity of the lower end opening of the small diameter passage 56b. The valve body 57 is always pressed downward by a spring means 60 such as a coil spring provided in the large diameter portion 56a. In this state, the packing 59 is pressed against the bottom surface of the large diameter portion 56a of the passage hole 56, and the valve is closed (see FIG. 8A). The lower end opening surface of the communication hole 56 is located in substantially the same plane as the lower surface of the recording head 21.

  The side edge of the upper case 31 extends to a position covering the upper end of the storage portion 34, and the other ends of the exhaust passages 51, that is, the connection ports 52 a to 52 d are individually communicated with the upper ends of the passage holes 56. ing.

The maintenance unit 4 includes a cap member 71 that covers the opening surface of the nozzle 22 of the recording head 21 so as to be openable and closable, and a plurality of small caps that individually cover the lower end surface of the exhaust valve means 26, that is, the opening surfaces of the small diameter portions 56b. Member 72. Both cap members 71 and 72 are moved upward and downward of the nozzle 22 and the exhaust valve means 26 when the carriage 9 is moved to the standby position (right end position in FIG. 1) by a vertical movement mechanism 73 similar to a known maintenance unit. It rises so as to be in close contact with the lower end surface, and descends so as to be separated from those surfaces at other positions. Further, the cap member 71 is connected to the suction pump 74 in the same manner as a known maintenance unit, and the ink and foreign matters that are thickened from the nozzles 22 are removed by suction by driving the suction pump 74.

  Each small cap member 72 has a protrusion 72 a protruding from the cap member. When the small cap member 72 is in close contact with the lower end surface of the exhaust valve means 26, the protrusion 72 a causes the bubble rod 58 to bias the spring means 60. The packing 59 is moved away from the inner bottom of the large-diameter portion 56a to open the valve. Each small cap member 72 is connected to the suction pump 74 through a common flow path, and bubbles accumulated in the second chambers 39a to 39d of the respective damper chambers are collectively sucked and discharged by driving the suction pump 74. Is done. This is because the ink supplied from the ink tank 5 through the ink supply pipe 14 is temporarily stored in the second chambers 39a to 39d, so that bubbles are separated and floated from the ink and accumulated in the upper portions of the second chambers 39a to 39d. The air bubbles are discharged by the suction pump 74 as described above.

  The cap member 71 and the small cap member 72 are alternatively connected to the suction pump 74 by a switching valve 75. The cap member 71 and the small cap member 72 are simultaneously brought into close contact with the opening surface of the nozzle 22 and the lower end surface of the exhaust valve means 26 by the vertical movement mechanism 73. Preferably, the second chamber is firstly passed through the small cap member 72. The bubbles accumulated in the upper portions of 39a to 39d are discharged, and then the ink is discharged from the nozzle 22 through the cap member 71. If the cap member 71 alone is used to discharge the bubbles in the second chambers 39a to 39d, a large amount of ink must be discharged. However, by doing the above, the bubbles can be discharged and recorded with a small ink discharge amount. Head recovery processing can be performed.

  In addition, only ink suction from the nozzles 22 or only discharge of bubbles in the second chambers 39a to 39d can be performed independently.

  In place of the suction operation of the suction pump 74 as described above, a positive pressure is applied to the ink from the ink tank 5 side to suck and remove thickened ink and foreign matter from the nozzle 22, or the second chambers 39a to 39a. The 39d bubbles can also be discharged. Alternatively, the suction operation and the positive pressure application to the ink can be used in combination.

  9 to 16 show a second embodiment of the present invention. In this embodiment, the ink colors are four colors of black, cyan, magenta, and yellow, and two recording heads 21 having a row of nozzles 22 for each color similar to the above embodiment are arranged in parallel in the main scanning direction. Arranged and fixed to the head holder 20.

  The damper device 63 according to the second embodiment supplies the corresponding color ink to the two recording heads 21. That is, there is one ink inlet 47 for each color, but two ink outlets 41 are formed. Hereinafter, the same parts and configurations as those of the first embodiment will be described with the same reference numerals.

  The main body case 25 in the damper device 63 of the second embodiment includes an upper case 31 and a lower case 32, and the upper case 31 is liquid-tightly fixed to the upper end of the lower case 32 by ultrasonic welding or the like. .

  In the lower case 32, a first chamber 27a-1 of a black ink (BK) damper chamber is formed under the main partition wall 35 in substantially the same manner as in the above embodiment, and the first chamber 27a-1 Most of the area of the lower surface of the case 32 is opened downward, and the flexible film 36 is bonded to cover the opened surface. A plurality of ink outlets 41a to 41d are disposed on the lower surface of the lower case 32 so as to be adjacent to the open surface of the first chamber 27a-1. In this embodiment, there are two ink outlets in the center, the ink outlet 41a for black ink (BK), the two ink outlets 41c on both sides thereof for yellow ink (Y), and two at one end. These are the ink outlet 41b for cyan ink (C) and the other two are the ink outlet 41d for magenta ink (M).

  The second chamber 39a of the black ink (BK) damper chamber is defined by a partition wall 35b formed so as to surround the two central ink outlets 41a in a plan view, and is formed to penetrate the main partition wall 35. The passage 42 communicates with the first chamber 27a-1. Further, the third chamber 55a formed on the upper surface of the upper case 31 and surrounded by the wall 30b located on the extended surface of the partition wall 35b is formed in the second chamber 39a by the air hole 54 formed through the upper case 31. Communicated with.

  The damper chambers 27b to 27d for the cyan ink (C), the yellow ink (C), and the magenta ink (M) have sub-partition walls 35a formed on the upper surface of the main partition wall 35, as in the above-described embodiment. And it is demarcated by the subpartition wall 30 formed in the upper surface of the upper case 31 on the extension surface. The damper chambers 27b to 27d are formed such that the upper side of the bottom wall 29 of the upper case 31 is a first chamber 27b-1 to 27d-1, and the lower side is a second chamber 39b to 39d. The second chambers 39b to 39d extend over the entire length of the lower case 32 in the longitudinal direction and communicate with the ink outlets 41b to 41d, respectively. In this embodiment, the second chamber 39c for yellow ink (C) is formed in a Y shape in plan view, and the second chamber 39b for cyan ink (C) is sandwiched between the second chamber 39c and magenta ink. A second chamber 39d for (M) is formed.

  The first chambers 27b-1 to 27d-1 on the upper surface of the upper case 31 are located above the corresponding second chambers. In this embodiment, the cyan ink (C) and yellow ink ( There is no third chamber for C) and magenta ink (M). In the bottom wall 29 of each first chamber, a plurality of passage holes 44 are formed on the side close to the communication passage 50 described later, and the passage holes 44 are formed on the sides close to the ink outlets 41b to 41d. The chamber communicates with the second chamber.

  The plurality of exhaust passages 51 are recessed in the upper surface of the upper case 31, one end communicates with each of the second chambers 39 a to 39 d through the exhaust hole 53, and the other end is a connection port for the exhaust valve means 26 having the same structure as the above embodiment. 52a, 52b, 52c, and 52d (see FIG. 11A). The exhaust holes 53 for the cyan ink (C), the yellow ink (C), and the magenta ink (M) are opened below the ceiling surface of the second chambers 39b to 39d, as in the above embodiment, and the second A space for storing air is secured at the top of the chamber.

  The upper open surfaces of the first chambers 27 b-1 to 27 d-1, the third chamber 55 a for black ink, and the exhaust passage 51 are covered with a single flexible film 43.

  In the lower case 32, ink inlets 47 a to 47 d are formed in substantially the same manner as in the above embodiment, and the black ink (BK) ink inlet 47 a is connected to the black ink (BK) damper via the concave passage 48. The ink inlets 47b to 47d for the cyan ink (C), the yellow ink (C), and the magenta ink (M) are connected to the chamber 27a and are connected to the corresponding damper chambers 27b to 27d via the communication paths 49 and 50. Each is connected. The open bottom surfaces of the ink inlets 47a to 47d and the concave passage 48 are sealed by extending the flexible film 36.

  In the first and second embodiments described above, when each ink supply tube 14 moves in the left-right direction as the carriage 9 reciprocates in the main scanning direction (left-right direction) in accordance with the recording operation, the return time is returned. The pressure of the ink in each ink supply tube 14 varies greatly due to the inertial force. The pressure fluctuation propagates to each damper chamber 27 via the ink inlet 47. At that time, the flexible films 36 and 43 sealing each damper chamber 27 are bent, so that the fluctuation of the ink pressure in each damper chamber 27 can be reduced.

  The pressure fluctuation propagated to the first chambers 27a-1 to 27d-1 of each damper chamber is first flexed in the first chambers 27a-1 to 27d-1 by the resistance action of the passage holes 44 and the passages 42 as the throttle portions. The flexible films 36 and 43 are greatly bent. Further, the communication paths 49 and 50 to the respective chambers 27b-1 to 27d-1 for cyan ink (C), yellow ink (C), and magenta ink (M) are close to the flexible film 43. Since the opening is made at the position, the pressure fluctuation directly collides with the flexible film 43 and is absorbed and relaxed at an early stage.

  In addition, since an air layer is normally secured in the upper portions of the second chambers 39a to 39d and the third chambers 55a to 55d, the damper action by the air and the flexibility to seal the third chambers 55a to 55d are provided. Due to the deformation of the film 43, the pressure fluctuation generated in the damper chambers 27a to 27d and the pressure fluctuation propagated as described above are absorbed and relaxed, the pressure at the nozzle 22 of the recording head 21 is maintained uniformly, and the recording quality is improved. It is done.

  The ink that has flowed into the first chambers 27a-1 to 27d-1 of each damper chamber is further decelerated by the resistance action of the passage holes 44 and the passages 42 as the throttle portions, and flows into the corresponding second chambers 39a to 39d. To do. In the second chambers 39a to 39d, bubbles contained in the ink are floated, and the ink in which the bubbles are reduced is supplied to the recording head 21 from the ink outlets 41a to 41d.

  In both the above embodiments, the nozzle surface of the recording head unit 3 is substantially horizontal and the ink is ejected downward from the nozzles 22 of the recording head 21. Therefore, the damper device 13 is disposed above the recording head 21 and the main unit thereof. The partition wall 35 and the flexible films 36 and 43 are disposed so as to be substantially horizontal, and between the lower flexible film 36 and the back surface of the recording head 21 (specifically, the flexible flat cable 24). A gap space in which the flexible membrane 36 can be displaced is formed. However, when the nozzle surface is vertically oriented, the damper device 13 extends in a direction in which the main partition wall 35 and the flexible membranes 36 and 43 extend vertically. May be arranged.

  As described above, in both embodiments, at least one damper chamber of the plurality of damper chambers 27 corresponding to a plurality of colors or a plurality of ink supply channels is connected to the other plurality of damper chambers via the main partition wall 35. And arranged in a back-to-back manner so as to have opening surfaces opposite to each other, and sealing each of the opening surfaces with flexible films 36 and 43, respectively, thereby making it possible to collect a plurality of damper chambers, By arranging the damper chambers 27 in a back-to-back manner, the area of the opening surface (open portion) of each damper chamber 27 can be made relatively large. Therefore, while making the entire damper device 13 compact, it is possible to set a large area area in which the flexible films 36 and 43 sealing the opening surfaces of the damper chambers 27 can be bent due to the pressure variation of the ink, so that the damper function is sufficient. Can be done. In particular, the damper device 13 can be compactly formed by collecting the plurality of damper chambers 27 in one main body case 25.

  As in the above-described embodiment, the three damper chambers 27 of the four damper chambers 27 are partitioned by the sub partition walls 35a and 30 orthogonal to (intersect with) the main partition wall 35, and are arranged in parallel. Since the plurality of damper chambers 27 having the opening surfaces can be sealed with the single flexible film 43, the sealing operation is extremely easy and the manufacturing cost can be reduced.

  If the exhaust passage 51 to the exhaust valve is formed in the main body case 25 having the plurality of damper chambers 27 and the exhaust valve means 26 is also integrated into the main body case 25, the bubbles in the recording head unit 3 are maintained during maintenance. A structure for removing the recording head unit 3 can also be mounted on the carriage 9, and the recording head unit 3 can be made compact. In particular, the exhaust passage 51 may be partitioned by the sub-partition wall 30 in the main body case 25 and arranged side by side, and may be formed to be recessed so as to open in the same direction as the opening surfaces of the damper chambers 27b-1 to 27d-1. For example, by sticking one flexible film 43 to the surface of the main body case 25, the damper chamber 27 and the exhaust passage 51 can be partitioned at the same time, and the manufacturing cost can be reduced.

  Since the air damper chambers 55a to 55d communicate with the second chambers 39a to 39d having a function as a buffer tank, the recording head unit 3 can be made compact, and the second chamber 39a can be moved along with the reciprocating movement of the carriage 9. It is also possible to suppress (relax) pressure fluctuations due to the oscillation of the ink stored in .about.39d.

  Further, the damper device 13 opens two opposing surfaces of the main body case 25, and forms a plurality of independent damper chambers 27 by a main partition wall 35 spaced from the two surfaces, and the two open surfaces are formed. The flexible films 36 and 43 are used for sealing. The main body case 25 is supplied with ink from an ink supply pipe (tube) 14 to each damper chamber 27 and to each ink supply channel of the recording head 21 from each damper chamber 27. And a plurality of ink inflow ports 47 and predetermined ones of the ink outflow ports 41 are communicating passages 49 and 50 extending in a direction substantially perpendicular to the surface formed by the main partition wall 35. Are connected to the corresponding damper chamber 27.

  Therefore, although the plurality of damper chambers 27 are separated by the main partition wall 35 and the sub partition walls 35a and 30, the ink outlet 41 and the ink inlet 47 can be formed side by side on one surface of the main body case. Therefore, the connection to the ink supply tube (tube) 14 and the connection to the ink supply port (not shown) of the recording head 21 can be facilitated.

  The recording head 21 has a plurality of ink supply ports connected to the ink supply channels arranged side by side on the back side of the recording head 21. The outflow ports 41 are arranged in the downward direction so as to face the ink supply ports, and the plurality of ink outflow ports 41 and the ink inflow ports 47 communicate with each other in a state of facing each other. Accordingly, when the main body case 25 is overlapped with the back surface of the recording head 21, the ink supply ports corresponding to the plurality of ink supply channels in the recording head 21 and the plurality of ink outlets 41 overlap and intersect the back surface of the recording head 21. The operation of connecting the ink supply tube 14 facing from the upper side to the ink inlet 47 can be facilitated.

  Next, a third embodiment will be described with reference to FIGS. The recording mechanism section 2 'in the third embodiment reciprocates slidably over horizontally long plate-shaped guide rails 6' and 7 'extending in the Y direction (the direction perpendicular to the paper transport direction X, the main scanning direction). A recording head unit 3 ′ constituting a moving carriage, a timing belt 11 ′ arranged in parallel with the upper surface of the guide rail 7 ′ for reciprocating the recording head unit 3 ′, and the timing belt 11 ′ A driving CR (carriage) motor 10 'is provided.

  As shown in FIGS. 18 and 19, the recording head unit 3 'has a substantially box-shaped main body 100a having an open top surface and a downstream side in the paper (recording medium) transport direction from the main body 100a (the direction of arrow A in FIG. 17). ) Projecting connection support piece 100b, an ink jet recording head 21 fixed to the lower surface side of the bottom plate 100c of the head holder 100, and a damper device 101 fixed to the upper side of the bottom plate 100c. And an exhaust valve means 102.

  The damper device 101 is provided with a connecting piece 103 that extends substantially horizontally on the downstream side of the paper conveyance (in the direction of arrow A in FIG. 17) and is supported by being overlapped with the connecting support piece 100b. The tip of the tube 14 'can be connected. This ink jet printer has individual ink tanks (not shown) of yellow ink (Y), magenta ink (M), cyan ink (C), and black ink (Bk) as ink supply sources for full color recording. The ink supply tube 14 'is connected to the base end of the ink tank. An ink flow path for supplying ink from the ink tank to the recording head 21 via the ink tube 14 ′ and the damper device 101 is formed. In this embodiment, there are four ink supply tubes 14 'because the ink colors are four colors of black ink (BK), cyan ink (C), yellow ink (Y), and magenta ink (M). The type of color and the number of ink supply tubes are not limited to this.

  Further, the upper surfaces of the damper device 101 and the exhaust valve means 102 and the upper surface of the connecting piece 103 of the damper device 101 are covered with lid cover bodies 106a and 106b, respectively (see FIG. 17).

  A number of nozzles 22 are provided on the lower surface of the recording head 21, and in FIG. 24 (view of the recording head 21 viewed from the lower surface), a nozzle row 22a for black ink (BK) and a cyan ink (C) are shown from the left side. The nozzle row 22b of yellow, the nozzle row 22c for yellow ink (Y), and the nozzle row 22d for magenta ink (M) are long in the direction orthogonal to the moving direction (Y direction, main scanning direction) of the carriage 5. Is formed. Each nozzle 22 is exposed downward so as to face the upper surface of the sheet.

  The recording head 21 has an ink supply port 107 for each ink color on one side of the upper surface, similar to those known in JP-A-2002-67312, JP-A-2001-219560, and the like. Ink is distributed to a number of pressure chambers via ink supply channels (manifolds) extending from the supply port 107, and ink is ejected from the nozzles 22 by driving actuators 23 such as piezoelectric elements corresponding to the pressure chambers. is there.

  As shown in FIG. 19, a flexible flat cable 24 that applies a voltage to the actuator 23 is fixed to the upper surface of the actuator 23. The recording head 21 is attached to the lower surface side of the bottom plate 100c of the head holder 100, and a reinforcing frame 108 is interposed between the recording head 21 and the bottom plate 100c in order to prevent the recording head 21 from being bent at the time of attachment. . The ink outlet 109 of the damper device 101 is inserted into the opening of the bottom plate 100c, and the ink supply port 107 and the ink outlet 109 of the damper device 101 are provided with rubber packing or the like via the opening 108a provided in the reinforcing frame 108. The seal material 110 is in communication. In addition, a U-shaped front frame 112 is attached to the nozzle surface (lower surface) side of the recording head 21 in order to eliminate a step difference in the nozzle surface.

  Next, the configuration of the damper device 101 according to the third embodiment will be described with reference to FIGS.

  The damper device 101 includes a plurality of independent damper chambers 113 for each ink color, which are partitioned by a main partition wall 115 and sub-partition walls 116 and 117 intersecting with the main partition wall 115. In the embodiment, a first chamber 119 a that is a part of a black ink (BK) damper chamber 113 is disposed under the main partition wall 115, and the black ink damper chamber 113 is disposed on the main partition wall 115. The second chamber 120, the cyan ink damper chamber 113b, the yellow ink damper chamber 113c, and the magenta ink damper chamber 113d, which are a part of the second chamber 120, are arranged in two layers in the vertical direction.

  Specifically, the main body case 121 in the damper device 101 includes an upper case 122 having a substantially rectangular shape in plan view, and a substantially box-shaped lower case 123 having a rectangular cylindrical side wall as an outer periphery and having upper and lower surfaces opened. It has. The upper and lower cases are liquid-tightly fixed (coupled) at the mating surfaces so that the upper surface of the lower case 123 is covered with the upper case 122. One end in the longitudinal direction of the upper surface portion of the upper case 122 is extended outward to form a connecting piece 103 for connection with the ink supply pipe 14 '. Both the upper case 122 and the lower case 123 are injection-molded with a synthetic resin material and have rigidity, and a joint portion (described in detail later) between both the cases 122 and 27 is ultrasonic welding or the like. (See FIGS. 19, 20, 21, and 22). In this case, the joint surfaces of the cases 122 and 123 are formed in a flat shape, and are formed at the upper end surface of each sub partition wall 116 that partitions damper chambers 113b to 113d described later and a part of the damper chamber 113a for black ink. The upper end surface of the sub-partition wall 117 that partitions a certain second chamber 120 and the lower surface portion of the upper case 122 corresponding thereto are intimately joined (coupled) by ultrasonic welding or the like.

  The lower case 123 is provided with an opening that opens most of its area on the lower surface thereof, and the main partition wall 115 is formed at a position spaced in parallel from the opening and the upper surface of the lower case 123. ing. The opening on the lower surface is sealed with a damper flexible film (synthetic resin film that is impermeable to air and liquid) 124. Specifically, the outer peripheral edge of the flexible film 124 is bonded to the lower end surface of the outer peripheral wall 125 that defines the outer periphery of the opening on the lower surface by bonding or ultrasonic welding (see FIGS. 25, 28, and 29). ).

  A first chamber (damper action chamber) 119a, which is a part of the black ink damper chamber 113a, is formed flat between the flexible film 124 and the main partition wall 115. The opposing surface, that is, the surface sealed with the flexible film 124 is a damper acting surface. In addition, as shown in FIG. 25, the damper device 101 is fixed between the flexible film 124 and the bottom plate 100c of the head holder 100 with a gap for deformation of the flexible film 124 secured. The holder 100 is installed so that the damper action surface (flexible film 124) of the damper action chamber 119a for black ink is substantially horizontal. Each of the ink outlets 109a to 109d connected to the ink supply port 107 of the recording head 21 is positioned side by side on the lower surface of the lower case 123 so as to face the four ink supply ports 107, and is a flexible film. It is opened downward at a position extending below 124 (see FIGS. 21 and 25). The recording head 21 is arranged with a row of nozzles 22 extending substantially parallel to the main partition wall 115.

  In the damper working chamber 119a for black ink, an ink inlet 126a to the damper working chamber 119a and a passage 127 from the damper working chamber 119a are formed in the main partition wall 115. In the damper working chamber 119a having a substantially rectangular shape in plan view, the damper working chamber 119a is disposed at a position that is substantially diagonal in plan view. The passage 127 has a larger opening area than the ink inlet 126a (see FIGS. 21, 22, and 27).

  Also, ribs 129 project from the damper working chamber 119a, and an ink path for guiding ink from the ink inlet 126a to the passage 127 is defined. In the embodiment, the rib 129 has two parallel linear shapes extending integrally with the lower surface of the main partition wall 115 and extending in a diagonal direction of the damper working chamber 119a (between the two ribs 129 ( An ink inlet 126a and a passage 127 are disposed on the inner side. Since the hanging length of the rib 129 is formed so as not to reach the flexible film 124, a gap is provided between the tip of the rib 129 and the flexible film 124. Therefore, in the vicinity of the main partition wall 115 serving as the ceiling portion of the damper working chamber 119a, the rib 129 hangs down from the ceiling portion. However, in the vicinity of the flexible film 124 serving as the bottom portion of the damper working chamber 119a, the bottom portion Ink is spread throughout (see FIGS. 28 and 29).

  On the upper surface of the main partition wall 115, the sub-partition walls 116, 117 are formed so as to rise integrally with the main partition wall 115, and a portion above the main partition wall 115 in the lower case 123 is formed, A plurality of damper chambers are formed together with the upper case 122.

  In the embodiment, as shown in FIG. 20, two sub-partition walls 116 are arranged to extend over the entire length of the lower case 123 with a space therebetween, and together with the side walls of the lower case 123, cyan ink, yellow ink, and Three damper chambers 113b to 113d for magenta ink are formed. Each sub partition wall 116 communicates the damper chambers 113b to 113d with the ink outlets 109b to 109d for each ink color at the end position of the main partition wall 115 (see FIG. 25).

  On the other hand, as shown in FIG. 20, the sub partition wall 117 is provided so as to partition the corner portion of the lower case 123 in the vicinity of the ink outlet 109 a together with the side wall of the lower case 123 into a substantially triangular shape in plan view. A second chamber 120 which is a part of the black ink damper chamber 113 a is formed between the sub partition wall 117 and the side wall of the lower case 123. In other words, the black ink damper chamber 113a includes a first chamber (damper action chamber) 119a and a second chamber 120 which are arranged vertically with the main partition wall 115 as a boundary. The area of the second chamber 120 in plan view is smaller than the area of the damper action chamber 119a in plan view, but a part of the second chamber 120 is disposed so as to overlap with the damper action chamber 119a in plan view. As shown in FIG. 28, a passage 127 formed in the main partition wall 115 serves as an ink inlet to the second chamber 120. The second chamber 120 is connected to an ink outlet 109 a provided at the end position of the main partition wall 115. As described above, in the second chamber 120, the chamber inlet (passage 127) and the chamber outlet (ink outlet 109 a) are both provided on the bottom side that is one surface of the second chamber 120.

  The second chamber 120 is provided so as to temporarily accumulate ink therein, and the ceiling surface 130a side formed by the upper case 122 serves as a bubble trapping region so that air bubbles separated from the ink are gradually accumulated. Yes. And the exhaust port 131a which penetrates the upper case 122 is provided in the ceiling surface 130a of the 2nd chamber 120 (refer FIG. 28). Further, the main partition wall 115 serving as the bottom surface (bottom wall) of the second chamber 120 is provided between the passage 127 (second chamber inlet) and the ink outlet (second chamber outlet) 109a. A rib 132 is provided to project between the passage 127 (second chamber inlet) side and the ink outlet (second chamber outlet) 109a side (see FIG. 28). The rib 132 has a protruding length that does not reach the ceiling surface 130a of the second chamber 120, and a width dimension that completely separates the passage 127 side and the ink outlet 109a side in the second chamber 120 on the bottom surface side (see FIG. Therefore, the ink that has flowed into the second chamber 120 from the passage 127 always flows along the rib 132 so as to detour upward, and then reaches the ink outlet 109. It is supposed to be.

  The upper case 122 has a plurality of recesses formed on the upper and lower surfaces thereof, and at the position near the connecting piece 103, three ribs 133 that continue in a rectangular ring shape integrally project toward the lower case 123, and this rib 133 Thus, three independent regions are enclosed (see FIG. 21).

  The three regions surrounded by the ribs 133 are formed in a generally rectangular shape in plan view and are opened up and down. When the upper case 122 and the lower case 123 are joined, the regions are formed in the lower case 123, respectively. The three damper chambers 113b to 113d are housed inside. The hanging length of the rib 133 is formed so as not to reach the main partition wall 115, and a gap is formed between the tip of the rib 133 and the bottom of each of the damper chambers 113 b to 113 d, that is, the main partition wall 115. It is configured as follows. The area surrounded by the rib 133 is a first area in which a predetermined amount of air is stored in advance in each of the damper chambers 113b to 113d for cyan ink, yellow ink, and magenta ink before the use of the ink jet printer. Chambers (damper action chambers) 119b to 119d.

  Since the air stored in each of the damper working chambers 119b to 119d is separated from the surroundings by the drooping of the rib 133, it is not exhausted from the exhaust ports 131b to 131d, which will be described later. The amount specified by the drooping length) is reliably stored. In addition, in order to seal the upper open surfaces of these three regions in common, a single flexible film for damper (synthetic resin air and liquid impermeable film) 136 surrounds these outer peripheries. It joins to the upper end surface of the outer peripheral wall to define by adhesion | attachment or ultrasonic welding.

  Further, in the damper chambers 113b to 113d for cyan ink, yellow ink, and magenta ink, the regions on the downstream side of the damper working chambers 119b to 119d (sides close to the ink outlets 109b to 109d) are respectively formed from the ink. The second chambers (bubble trap chambers) 135b to 135d are provided so as to gradually accumulate the separated and floated bubbles. In each of the damper chambers 113b to 113d, a rib 132 projects from the main partition wall 115 between the ink outlets 109b to 109d on the downstream side of the damper working chambers 119b to 119d (see FIG. 29). The rib 132 has a protruding length that does not reach the ceiling surface 130a of the bubble trap chambers 135b to 135d, and a width dimension that completely separates the ink outlets 109a to 109d in the bubble trap chambers 135b to 135d on the bottom surface side. Therefore, the ink that has flowed into the damper chambers 113b to 113d always flows so as to detour upward along the rib 132, and then reaches the ink outlets 109b to 109d.

  The ceiling surfaces 130b to 130d of the bubble trap chambers 135b to 135d are constituted by the upper case 122, and exhaust ports 131b to 131d penetrating the upper case 122 are formed in the ceiling surfaces 130b to 130d (FIGS. 22 and 22). 29).

  As described above, the end of the upper case 122 in the direction of the arrow A is the connecting piece 103, but on one side edge side of the connecting piece 103, the supply tube connecting port 137 ( In the embodiment, four supply tube connection ports for black ink, cyan ink, yellow ink, and magenta ink are indicated by 137a, 137b, 137c, and 137d, respectively (see FIGS. 18 and 18). 23, FIG. 26 and FIG. 28).

  Each of these supply tube connection ports 137 is connected to an ink supply tube 14 'via a joint member 138 having a flow path for each ink color. Each supply tube connection port 137 communicates with each damper chamber 113 through passages provided in the upper case 122 and the lower case 123 (see FIGS. 20, 21, and 22).

  In this embodiment, as shown in FIGS. 21, 22, 23, 26, 27, and 28, as an ink flow path for black ink, first, the connection piece 103 of the upper case 122 is connected to the supply tube connection port. A first concave passage 139a having a groove 137a at one end and opened downward on the lower surface of the connecting piece 103, and the upper and lower surfaces of the connecting piece 103 at the other end of the first concave passage 139a. A first communication hole 140a formed in a penetrating manner, a second concave passage 141a having the first communication hole 140a at one end and opened upward on the upper surface of the connection piece 103, and formed in an L shape, A second communication hole 142a is formed in the other end of the second concave passage 141a so as to penetrate the upper and lower surfaces of the upper case 122. On the other hand, as shown in FIG. 20, a third communication hole 143 is formed through the lower case 123 at a corner portion adjacent to the magenta ink damper chamber 113d and far from the ink outlet 109d. The lower opening of the third communication hole 143 is provided in the main partition wall 115, and this opening serves as the ink inlet 126a to the black ink damper working chamber 119a. Then, when the upper case 122 and the lower case 123 are joined, the upper end surface of the third passage hole 143 and the lower end surface of the second passage hole 142a are brought into close contact with each other, whereby a black ink supply tube is obtained. The connection port 137a is connected to the damper working chamber 119a (damper chamber 113a).

  As ink flow paths for cyan ink, yellow ink, and magenta ink, as shown in FIG. 21, FIG. 22, FIG. 23, FIG. 26, FIG. Each of the first concave passages 139b to 139d having a connection port 137b to 137d at one end and opened downward on the lower surface of the connecting piece 103 and formed in an L shape, and the other end of the first concave passages 139b to 139d The first communication holes 140b to 140d that are formed through the upper and lower surfaces of the connecting piece 103 and the first communication holes 140b to 140d at one end thereof are opened upward on the upper surface of the connecting piece 103. Second concave passages 141b to 141d and second communication holes 142b to 142d formed through the upper and lower surfaces of the upper case 122 at the other ends of the second concave passages 141b to 141d, respectively. It is provided. These function as ink flow paths from the supply tube connection ports 137b to 137d to the damper chambers.

  The second communication holes 142b to 142d are provided integrally with the rib 133 and protrude downward slightly longer than the protruding length of the rib 133. The lower openings of the second communication holes 142b to 142d are ink inlets 126b to 126d to the damper chambers 113b to 113d, respectively (see FIGS. 21 and 22). Accordingly, the supply tube connection ports 137b to 137d for cyan ink, yellow ink, and magenta ink are connected to the respective damper chambers 113b to 113d.

  Further, as described above, the upper case 122 is formed with exhaust ports 131a to 131d communicating with the second chamber 120 and the second chambers (bubble trap chambers) 135b to 135d, and the exhaust ports 131a to 131d. Are connected to a plurality of exhaust passages 145 a to 145 d that are recessed independently of each other on the upper surface of the upper case 122. The exhaust passages 145 a to 145 d extend while bending in a direction orthogonal to the longitudinal direction of the upper case 122, and the other end is connected to the exhaust valve means 102.

  The first concave passages 139a to 139d formed on the lower surface of the connecting piece 103 are commonly covered by a single film material 134 bonded to the lower end of the outer peripheral wall defining the outer periphery thereof by bonding or ultrasonic welding. Each is formed as a flow path. The film material 134 is made of a synthetic resin such as PET, and may be a flexible film. Further, the second concave passages 141a to 141d and the exhaust passages 145a to 145d are portions in which the damper flexible film 136 is extended, and are commonly covered by the same method and are formed as flow paths.

  The connecting piece 103 is formed integrally with the lower case 123, and the first concave passages 139a to 139d are formed on the lower surface or the upper surface, and then the first concave passage 139a is formed with the film material 134 or the flexible film. The open surface of ˜139d may be sealed.

  Next, the exhaust valve means 102 will be described. As shown in FIGS. 20A and 21B, the storage portion 146 integrally provided on one side of the lower case 123 has an ink color for each ink color. Four passage holes 147 are formed so as to be long in the vertical direction and open vertically. The side edge of the upper case 122 is extended to a position that covers the upper end of the storage portion 146, and the opening portions 148 at the other ends of the exhaust passages 145 a to 145 d are individually communicated with the upper ends of the passage holes 147. . As in the first embodiment, the storage portion, that is, the exhaust valve box 146 is connected to the lower case 123 at the upper portion, extends downward with a gap 162 (FIG. 31) therebetween, and has an internal passage hole 147. The lower end opening surface is opened in substantially the same plane as the lower surface (nozzle surface) of the recording head 21. The side wall of the head holder 20 is inserted in the space between the storage portion 146 and the lower case 123. In addition, the valve body 57, packing 59, spring 60, and the like (see FIG. 30) are housed in the passage holes 147 as in the first and second embodiments. Driven to open and close the lower end opening of 147. When the recording head unit 3 'moves to the position of a maintenance unit (not shown) in the ink jet printer (such as the right end in FIG. 17), the valve element is driven to open the lower end opening of the passage hole 147, and the first and Similar to the second embodiment, the lower end opening is sucked by the suction pump. As a result, the bubbles accumulated in the air trap regions of the damper chambers 113a to 113d can be exhausted through the exhaust ports 131a to 131d and the exhaust passage 145.

  According to the above configuration, first, ink in an ink tank (not shown) is supplied to the damper device 101 from the supply tube connection port 137 through the ink supply tube 14. As shown in FIG. 28, the black ink passes from the supply tube connection port 137a through the first concave passage 139a and the second concave passage 141a of the connecting piece 103 and from the ink inlet 126a to the lower surface side of the main partition wall 115. It flows into the first chamber (damper action chamber) 119a. The pressure fluctuation of the ink propagated from the ink inlet 126a directly hits the flexible film 124 (damper acting surface) facing the ink inlet 126a, and the ink pressure fluctuation is reliably absorbed (damped) over a wide area. Then, the black ink is discharged together with bubbles from the passage 127 having a wide opening area by the rib 129 hanging from the ceiling of the damper working chamber 119a.

  The black ink flowing out from the passage 127 flows into the second chamber 120 formed on the upper side of the main partition wall 115. Since the second chamber 120 is disposed above the damper working chamber 119a, the bubbles rise without flowing and flow into the second chamber 120. In the second chamber 120, ink is collected and supplied to the recording head 21 side, but the ink that flows in from the bottom side of the second chamber 120 passes over the rib 132 and reaches the ink outlet 109 a that is also provided on the bottom side. . Bubbles separated and floated from the ink in the meantime are gradually accumulated in the bubble trap region on the ceiling surface 130a side. Then, the black ink is supplied from the ink outlet 109 a to the black ink supply port 107 of the recording head 21.

  On the other hand, as shown in FIG. 29, the cyan ink, the yellow ink, and the magenta ink flow from the supply tube connection ports 137b to 137d through the first concave passages 139b to 139d and the second concave passages 141b to 141d, respectively. It flows into the damper chambers 113b to 113d from the inlets 126b to 126d. In the damper chambers 113b to 113d, the damper working chambers 119b to 119d in which a certain amount of air is stored in advance and the ceiling portion is covered with the flexible film 136 are disposed on the upstream side in the interior thereof. The flexible film 136 and air cooperate to absorb (dump) ink pressure fluctuations. The bubbles separated and floated from the ink flowing into the damper chambers 113b to 113d are gradually accumulated in the second chambers (bubble trap chambers) 135b to 135d.

  When the recording head unit 3 'moves to the maintenance position and the exhaust valve means 102 is connected to the suction pump as a bubble removal maintenance operation as in the first embodiment, the second chambers 120, 135b to 135d are used. The air bubbles accumulated in the air are exhausted from the exhaust ports 131a to 131d through the exhaust passages 145a to 145d and the exhaust valve means 102 to the outside.

  As described above, in the above configuration, the rib 132 is provided so as to protrude upward from the bottom surface of the second chamber 120, and the second chamber inlet (passage 127) side and the second chamber outlet (ink outlet 109 a). The side is defined (defined). Since the rib 132 has a wall shape and does not have a mesh like a filter, the ink flowing out from the passage 127 does not necessarily pass through the path over the rib 132, and the ink outlet 109a provided on the bottom side is also provided. Can not reach. Therefore, regardless of the size of the bubbles contained in the ink, the bubbles are prevented from flowing directly to the ink outlet 109a with the momentum of inflow. Since the bubbles once rise along the ribs 132 together with the ink, the bubbles easily separate and float in the bubble trap region provided on the ceiling surface 130a side of the second chamber 120. As a result, ejection failure due to bubbles in the recording head 21 can be reliably prevented.

  In the black ink flow path, a first chamber (damper action chamber) 119a for absorbing ink pressure fluctuations is configured separately from the second chamber 120 for accumulating bubbles in the ink. In the case of black ink, the frequency of use is higher and the amount of ink supplied is larger than other color inks, so the pressure wave transmitted to the ink is also large. However, by making the damper action chamber 119a independent, high dynamic pressure absorption is achieved for the ink. It can be set as the structure which exhibits an effect.

  Even if the damper working chamber 119a and the second chamber 120 are formed separately, they share the main partition wall 115 and are arranged vertically so as to overlap in plan view, so that the overall configuration is small. be able to.

  Furthermore, since the rib 132 is provided integrally with the lower case 123 that constitutes the bottom wall side of the second chamber 120, the upper case 122 and the lower case 123 are simply overlapped and joined to each other. Therefore, the second chamber 120 (damper device 101) having the rib 132 can be easily formed.

  A surface (sealing surface) for adhering the flexible film 124 to the lower surface of the lower case 123 and a surface (sealing surface) for adhering the flexible film 136 and the film material 134 to the upper and lower surfaces of the upper case 122 are as follows. The upper and lower cases 122 and 123 lie on a plane substantially parallel to the mating surface, and therefore, the attaching operation of these members is easy to execute.

  Specifically, on the upper surface of the upper case 122, the damper working chambers 119b to 119d, the second concave passages 141a to 141d, and the exhaust passages 145a to 145d are defined above the protruding walls (outer peripheral walls) 150. A flexible film 136 is bonded (sealed) to the end face (see the hatched portion in FIG. 23 belonging to the same plane) by bonding or ultrasonic welding. Further, on the lower surface of the upper case 1122, the film material 134 is bonded (sealed) to the upper end surface of the ridge wall 151 (see FIG. 27) defining the outer circumference of each of the first concave passages 139a to 139d by sealing or ultrasonic welding. ) Similarly, a flexible film 124 is bonded (sealed) to the upper end surface of the outer peripheral wall 125 (see FIG. 27) defining the outer periphery of the black ink damper working chamber 119a on the lower surface of the lower case 1123 by sealing or ultrasonic welding. Stop).

  Thus, the upper end surface of the ridge wall (outer peripheral wall) 150, the upper end surface of the ridge wall 151, and the upper end surface of the outer peripheral wall 125 are parallel to the mating surfaces of the upper and lower cases 122 and 123, respectively. For example, after the upper and lower cases 122 and 123 are joined together, the respective flexible membrane 124 and the film material 134 are bonded and ultrasonically welded at the same time, so that the cases 122 and 123 are reversed and the rear flexible The process of sealing work can be simplified such that the sealing work of the conductive film 136 is performed.

  Next, the mounting structure of the damper device 101 to the head holder 100 in the third embodiment will be described with reference to FIGS. 19, 24, 30 and the like.

  The main body 100a of the head holder 100 is integrally formed with three side walls 100d having a large height and a side wall 100e having a slightly lower height so that the damper device 101 can be inserted from above. It is a thing.

  Further, at least two flange portions 160 as fixing portions (attachment arm portions) are integrally formed substantially horizontally in the X direction on the outside of the low side wall 100e. A mounting hole 161 penetrating vertically is formed. The recording head 21 is bonded to the lower surface of the reinforcing frame 108, and the unit of the recording head 21 and the reinforcing frame 108 is fixed to the lower surface of the bottom plate 100c with an adhesive.

  On the other hand, on the outer surface of the storage portion 146, reinforcing attachment arms 163 having a substantially T-shaped cross section are integrally formed at both ends in the Y direction (both ends in the row direction in which the valve elements 57 are arranged). (See FIGS. 19, 20, 21, 24, and 30). A pin 164 for heat caulking is integrally formed on the lower surface of the horizontal plate 163a in each mounting arm portion 163.

  With the above configuration, the sealing material 110 is interposed between the lower surface of the lower case 123 of the damper device 101 and the upper surface of the reinforcing frame 108. The ink outlets 109a to 109d and the corresponding ink supply ports 107 in the recording head 21 can communicate with each other in the seal material 110, and adjacent ink connection ports and ink supply ports are partitioned (defined). A plurality of corresponding holes are formed as shown in FIG.

  Then, the damper device 101 is inserted from above the main body 100 a of the head holder 100. At this time, the storage portion 146 of the exhaust valve means 102 is set so as to be located outside the low side wall 100e. As a result, the low side wall 100e is inserted into the gap 162 between the storage portion 146, which is the exhaust valve box portion, and the lower case 123.

  Next, the screws are fixed to the screw holes 167 of the reinforcing frame 108 with screws (screws) 166 through the mounting holes 165 formed in the lower case 123 at positions corresponding to both ends in the longitudinal direction of the sealing material 110 (see FIG. 31). In this state, the horizontal plate 163a of the mounting arm portion 163 in the storage portion 146 and the flange portion 160 in the head holder 100 face each other, and the pin 164 fits in the mounting hole 161. When the pin 164 protruding from the lower surface of each flange portion 160 is pressed from the lower end side with a heating tool (not shown), the pin 164 which is a thermoplastic synthetic resin is softened to become a heat caulking portion 169 as shown in FIG. The damper device 101 and the exhaust valve means 102 are integrated with the head holder 100 so that they cannot be detached and are firmly fixed.

  As described above, the horizontal plate 163a and the flange portion 160 are parallel to the contact surface between the ink connection port and the ink supply port. In other words, the direction in which the pin 164 is fitted into the mounting hole 161 is the ink outlet and the ink. Since the direction coincides with the direction facing the supply port, the reliability of the liquid-tight action by the sealing material 110 can be improved by fixing the pin 164 and the mounting hole 161. Also, by crimping with heat, the fixing operation can be performed easily and quickly as compared with the case of screw tightening, and since it cannot be detached, there is no rattling of internal parts and the reliability of the recording head unit 3 'is improved. .

In the attached state, the damper device 101 accommodated in the head holder 100, the recording head 21, and the flexible flat cable 24 fixed to the upper surface thereof are surrounded by the side walls 100d and 100e on the four sides of the head holder 100. When the lower surface (nozzle surface) of the recording head 21 is periodically wiped with a wiper, maintenance work, or exhaust operation, the ink adhering to the lower surface of the recording head 21 or the lower surface side of the storage portion 146 is removed from the side wall 100d, 100e or the like does not enter the head holder 100, and an electrical short circuit accident or the like can be reliably prevented.
. Needless to say, the present invention can be applied to various types of inkjet printers.

It is a top view of the recording mechanism part of an inkjet printer. It is a bottom view of a head holder. FIG. 3 is a cross-sectional view taken along the line III-III in FIG. 2. It is a top view of the damper device in the state where the flexible membrane 43 of the first embodiment is removed. It is a bottom view of a damper device in the state where flexible membrane 36 is removed. It is a top view of a lower case. (A) is a bottom view of only the upper case, and (b) is a plan view of only the upper case. (A) is a sectional view taken along line VIIIa-VIIIa in FIG. 4, (b) is a sectional view taken along line VIIIb-VIIIb in FIG. 4, and (c) is a sectional view taken along line VIIIc-VIIIc in FIG. It is an upper perspective view of the damper device of the second embodiment and its flexible membrane. It is a lower perspective view of the damper device of the second embodiment and its flexible membrane. (A) is an upper perspective view of the main body case (a state where the lower case and the upper case are combined) of the second embodiment, and (b) is a lower perspective view. (A) is an upper perspective view of the lower case of 2nd Embodiment, (b) is a lower perspective view. (A) is an upper perspective view of the upper case of 2nd Embodiment, (b) is a lower perspective view. It is a top view of a lower case. (A) is a front view of an upper case, (b) is XVb-XVb arrow directional cross-sectional view of Fig.15 (a). (A) is the XVIa-XVIa arrow directional cross-sectional view of Fig.15 (a), (b) is XVIb-XVIb arrow directional cross-sectional view of Fig.15 (a). It is a perspective view of the recording mechanism part in the inkjet printer of 3rd Embodiment. FIG. 10 is a perspective view of a recording head unit according to a third embodiment. FIG. 10 is an exploded perspective view of a recording head unit according to a third embodiment. (A) is an upper perspective view of an upper case, (b) is an upper perspective view of a lower case. (A) is a lower perspective view of the lower case, (b) is a lower perspective view of the upper case, (A) is a lower perspective view of a lower case, (b) is a lower perspective view of an upper case. FIG. 4 is a plan view of the recording head unit in a state where a flexible film on an upper surface of an upper case of the damper device is removed. It is a bottom view of the recording head unit. FIG. 24 is a cross-sectional view taken along line XXV-XXV in FIG. 23 in a state where a flexible film is attached to the upper surface of the upper case of the damper device. It is a top view of the state which removed the flexible film | membrane of the upper surface of the upper case of a damper apparatus. It is a bottom view of the state which removed the flexible film | membrane of the lower surface of the lower case of a damper apparatus. FIG. 27 is a cross-sectional view taken along the line XXVIII-XXVIII in FIG. 26 in a state in which the flexible membrane of the damper device is attached. FIG. 27 is a cross-sectional view taken along line XXIX-XXIX in FIG. 26 in a state in which a flexible membrane of the damper device is attached. FIG. 20 is a cross-sectional view taken along line XXX-XXX in FIG. 19. FIG. 24 is a cross-sectional view taken along line XXXI-XXXI in FIG. 23.

3, 3 'recording head unit 13, 101 damper device 14a-14d ink supply tube 20, 100 head holder 21 recording head 22 nozzle 24 flexible flat cable 25, 121 body case 26, 102 exhaust valve means 27, 27a-27d damper chamber 30, 116, 117 Subpartition wall 31, 122 Upper case 32, 123 Lower case 34, 146 Storage part 35, 115 Main partition wall 36, 43, 124, 136 Flexible membrane 39, 39a-39d Ink flow path 41a- 41d, 109a to 109d Ink outlet (head connection port)
42 passage 44 passage hole 47, 47a-47d ink inlet 49, 50 communication passage 51 exhaust passage 55a-55d air damper chamber 57 valve element 113 damper chamber 119 damper working chamber (first chamber)
120 Second chamber 129, 132, 133 Rib 131 Exhaust port 145 Exhaust passage 135 Bubble trap chamber

Claims (14)

An ink jet recording head is mounted on a carriage that moves relative to a recording medium, and ink is supplied to the recording head from an ink tank mounted on the main body via an ink supply pipe and a damper device mounted on the carriage. In an inkjet printer configured to supply,
The recording head has a plurality of ink supply channels of three or more ,
The damper device has a plurality of damper chambers partitioned to correspond to the plurality of ink supply channels,
Each damper chamber includes an ink inlet from the ink supply pipe and an ink outlet to the ink supply channel,
One damper chamber among the plurality of damper chambers is arranged back-to-back through the main partition wall with respect to the other plurality of damper chambers ,
The one damper chamber and the plurality of damper chambers each have a flexible film facing the main partition wall,
The main partition wall is disposed along a horizontal direction, and is configured such that the one damper chamber overlaps all of the plurality of damper chambers when viewed from a vertical direction orthogonal to the main partition wall. The inkjet printer is further characterized in that the one damper chamber is disposed below the main partition wall and the plurality of damper chambers are disposed above the main partition wall . The damper device is disposed above the recording head,
The inkjet printer according to claim 1, wherein the one damper chamber is disposed so as to face the recording head . The outlet of the one damper chamber is provided in the main partition wall, and similarly, the outlet of the plurality of damper chambers is provided in the main partition wall. Item 3. The inkjet head according to Item 1 or 2. The recording head includes a first ink supply channel through which a liquid that is used most frequently among liquids that flow through the plurality of ink supply channels, and a plurality of second ink through which liquid that is used less frequently than the first ink supply channel flows. Two ink supply channels,
4. The first ink supply channel according to claim 1, wherein the first ink supply channel communicates with the one damper chamber, and the plurality of second ink supply channels communicate with the plurality of damper chambers. The ink jet head according to any one of the above. The inkjet head according to claim 4, wherein black ink flows through the first ink supply channel, and color inks other than black flow through the plurality of second ink supply channels . Each of the damper chambers communicates with an exhaust passage to an exhaust valve for discharging bubbles to the atmosphere,
6. The ink jet printer according to claim 1, wherein the exhaust passage is formed integrally with a main body case forming a damper device, and the exhaust valve is integrated with the damper device . The main body case is composed of a box-shaped lower case whose upper and lower surfaces are opened, and an upper case disposed on the upper surface side of the lower case,
An exhaust valve box portion in which the exhaust valve is accommodated and a damper box portion constituting a plurality of damper chambers are integrally formed in the lower case,
The damper case part which covers the upper surface side of the said damper box part, and the exhaust passage which connects the said damper box part to the said exhaust valve box part are integrally formed in the said upper case. The inkjet printer described in 1. The ink jet printer according to claim 7 , wherein the upper and lower cases are liquid-tightly coupled to each other at their mating surfaces . It is an open surface of the upper case facing the mating surface, and the damper lid and the exhaust passage are sealed with a flexible film,
The inkjet printer according to claim 7, wherein the damper box portion, which is an open surface of the lower case facing the mating surface, is sealed with a flexible film . In the upper case or the lower case, an ink flow path communicating from the ink supply pipes to the damper chambers is formed as a recess,
8. The ink jet printer according to claim 7 , wherein an open surface in each ink flow path is sealed with a flexible film or a film material . 11. The inkjet printer according to claim 8 , wherein a sealing surface of each of the flexible films and the film material is a plane parallel to the mating surface . A head holder that supports the recording head in a state of facing the recording medium and accommodates the damper device; and an exhaust valve box portion that communicates with the exhaust passage and accommodates the exhaust valve;
An ink outlet port of the damper device and an ink supply port of the recording head are arranged to face each other, and a seal member is interposed between them,
8. The inkjet printer according to claim 7 , wherein the exhaust valve box portion is fixed to the head holder in a direction in which the ink outlet and the ink supply port face each other . The inkjet printer according to claim 12, wherein the fixing portion between the exhaust valve box portion and the head holder includes a pin and a hole that are fitted in a direction in which the ink supply port faces. The passage in the exhaust valve box portion is opened in parallel with the direction in which the ink outlet and the ink supply port face each other, a mounting arm portion protruding from a side surface of the exhaust valve box portion, and a head facing the head. The inkjet printer according to claim 13, wherein the pin and the hole are provided in a mounting arm portion of the holder .

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