JP2005271546A5 - - Google Patents

Description

Inkjet printer

  The present invention relates to an ink jet printer, and more particularly to an ink jet printer provided with a damper device in the middle of an ink flow path from an ink supply source to a recording head.

  Conventionally, an ink jet printer of a tube supply type that supplies ink to a recording head mounted on a moving carriage from an ink supply source fixed in the main body of the ink jet printer via a flexible tube (ink supply tube). It has been known.

  In the tube supply type ink jet printer, since the tube needs to be displaced according to the movement of the carriage, a flexible tube is used. However, the flexible tube avoids air permeation. I can't. As a result, there is a problem that air is dissolved in the ink in the tube, which becomes bubbles and flows into the recording head side together with the ink, causing ejection failure during recording.

  Also, in a tube supply type ink jet printer, excessive acceleration is imparted to ink in the tube due to acceleration / deceleration of the reciprocating carriage, and the pressure wave propagates to the ink in the recording head. As a result, the pressure wave has an adverse effect on the meniscus formed in the nozzles of the recording head, and there is a problem that recording quality is impaired.

  Therefore, for example, in Patent Document 1, an air trap (corresponding to a damper device) is mounted on the carriage upstream of the recording head in the ink flow path, and bubbles in the ink are separated by this air trap. A structure that accumulates and absorbs the dynamic pressure applied to the ink is described. The air trap of Patent Document 1 is provided with an ink inlet from an ink supply source and an ink outlet to the recording head on the bottom side. In the air trap, the first chamber on the ink inlet side and the second chamber on the ink outlet side communicate with each other on the ceiling surface side and are partitioned by the first filter on the bottom surface side. Further, in the first chamber, a bubble reservoir is recessed and opened downward on the ceiling surface which is an extension of the ink inlet. Further, the ink outlet is provided on the bottom surface side of the side wall forming the second chamber, and a second filter is attached thereto.

In the air trap of Patent Document 1 configured as described above, the dynamic pressure of ink propagated from the ink inlet is absorbed (damped) by the bubbles stored in the bubble reservoir in advance. In addition, bubbles included in the ink float to the ceiling surface side of the air trap and gradually accumulate. When the amount of bubbles in the air trap exceeds a predetermined amount, suction is performed from the nozzle surface side of the recording head as a purge process, and the bubbles are discharged through the recording head together with ink.
JP 2002-166568 A (see FIGS. 3 and 6)

  However, in the structure of the air trap of Patent Document 1, the recording head is arranged in parallel with the vertical direction of the second chamber, so that the ink outlet extends horizontally from the bottom surface of the second chamber toward the recording head and reaches the tip of the recording head. The second filter is arranged, the flow path from the second chamber to the second filter is bent, and the air bubbles caught on the second filter cannot rise quickly and reach the ceiling surface side. It tends to grow greatly around the second filter. As a result, there is a problem that the air bubbles cause the second filter to be blocked, and the ink supply to the recording head side is insufficient, resulting in a state where ejection is impossible.

  In addition, in the air trap of Patent Document 1, the dynamic pressure of ink is absorbed by the bubbles in the bubble reservoir recessed on the ceiling surface side, but it is desired to increase the absorbability with respect to the dynamic pressure of ink with a simpler structure. There was also a request.

  The present invention solves the above problem, and in a damper device of an ink jet printer, it is possible to separate bubbles contained in the ink and quickly supply the ink to the recording head, and further against the dynamic pressure of the ink. The object is to realize a structure having high absorbability (damping).

In order to solve the above problems, an ink jet printer according to the first aspect of the present invention includes an ink jet recording head mounted on a carriage that moves relative to a recording medium, and supplies ink from an ink supply source mounted on the main body. In an inkjet printer configured to supply ink to the recording head via a damper device mounted on the carriage via a tube, the damper device absorbs the dynamic pressure of the ink flowing from the ink supply tube a damper working chamber which, e Bei ink reservoir chamber and a bubble trap chamber the air bubbles contained in the ink to accumulate, the ink reservoir chamber, in substantially vertically downward of said bubble trap chamber, the ink reservoir chamber of the ink Connected to a head connection port for supplying the recording head to the recording head, and on the ceiling surface of the bubble trap chamber, The head connection port is connected to an exhaust port that is positioned substantially vertically above the head connection port and capable of discharging the bubbles in the bubble trap chamber to the outside. The ink reservoir chamber has the abbreviated head connection port and the exhaust port facing each other. The damper action chamber extends laterally with respect to the vertical direction and is separated from the bubble trap chamber, and ink from the ink supply pipe is removed from the damper action chamber on the opposite side of the bubble trap chamber. are connected with the ink inlet port for receiving is characterized in Rukoto.

According to the second aspect of the present invention, an ink jet recording head is mounted on a carriage that moves relative to a recording medium, and each ink is supplied from a plurality of ink supply sources mounted on the main body via an ink supply pipe. In the ink jet printer configured to be supplied to the recording head via a damper device mounted on the carriage, the damper device includes a damper working chamber that absorbs dynamic pressure of ink flowing from the ink supply pipe, and an ink An ink reservoir chamber having a bubble trap chamber for accumulating bubbles contained in the ink reservoir. Connected to the head connection port to be supplied, and on the ceiling surface of the bubble trap chamber, the head connection port A set of the bubble trap chamber and the head connection port of one of the ink reservoir chambers is connected to an exhaust port that is located vertically above and can discharge the bubbles in the bubble trap chamber to the outside. The bubble trap chamber and the head connection port are positioned substantially parallel to each other, and the ink reservoir chamber has a substantially vertical direction in which the head connection port and the exhaust port face each other. An ink inlet port that extends laterally and has the damper action chamber at a position away from the bubble trap chamber, and receives ink from the ink supply pipe on the opposite side of the damper action chamber to the bubble trap chamber. And the plurality of damper working chambers are parallel to each other in a direction from the ink inlet to the bubble trap chamber .

According to a third aspect of the present invention, in the ink jet printer according to the first or second aspect, the damper working chamber has a direction from the ink inflow port toward a position where the head connection port and the exhaust port face each other. and it is characterized in that it is sealed by a flexible membrane parallel faces.
According to a fourth aspect of the present invention, in the ink jet printer according to any one of the first to third aspects, the head connection port and the exhaust port face the damper working chamber from a position lower than the ceiling surface. It is connected to the bubble trap chamber so as to supply ink to a position where the ink is to be discharged.

According to a fifth aspect of the present invention, in the ink jet printer according to the second aspect, the recording head has a plurality of ink supply ports connected to a plurality of ink supply channels, and the damper device includes the plurality of inks. The head connection port corresponding to the supply port is arranged on the bottom surface of the end portion .

According to a sixth aspect of the present invention, in the ink jet printer according to the fifth aspect, the damper device has a main body case, and the plurality of bubble trap chambers are provided in the vicinity of one end of the main body case by a partition wall. It is characterized by being partitioned from each other .
The invention according to claim 7 is the ink jet printer according to claim 6, wherein the main body case includes an upper case having the ceiling surface and the plurality of exhaust ports, and a lower case having the plurality of head connection ports. The upper case has a plurality of exhaust passages respectively connected to the plurality of exhaust ports.

According to an eighth aspect of the present invention, in the ink jet printer according to the sixth aspect , each of the damper working chambers is formed to extend from the one end side to the other end side of the main body case, and the ink supply pipes are connected to each other. A plurality of passages extend from a joint member having a flow path for each ink, and the front ends of the passages serve as the ink inlet and are connected to the end of the damper working chamber on the other end side. It is.

According to the first aspect of the present invention, ink flows from the ink supply pipe into the damper action chamber, and from the side of the damper action chamber to the substantially vertical direction in which the bubble trap chamber exhaust port faces. At that time, the dynamic pressure is immediately absorbed in the damper working chamber. Further, since the bubble trap chamber is disposed substantially vertically above the head connection port, the bubbles are easily separated from the ink flowing out from the ink reservoir chamber to the recording head, and the bubbles are lifted as they are without being caught on the way. The trap chamber can be easily reached. Therefore, the head connection port can be prevented from being clogged with air bubbles, and ink can be supplied to the recording head without any stagnation.

According to the second aspect of the present invention, in the case of using a plurality of inks, the effect of the first aspect can be achieved for each ink, and the arrangement of the bubble trap chambers and the damper chambers for the plurality of inks is simplified. Can be.

According to the third aspect of the invention, the damper working chamber is sealed with the flexible film on the surface parallel to the direction from the ink inlet to the position where the head connection port and the exhaust port face each other. The dynamic pressure of the ink flowing from the ink inlet to the head connection can be effectively absorbed. According to the fourth aspect of the present invention, bubbles are accumulated in the bubble trap by supplying ink from a position lower than the ceiling surface to a position where the head connection port and the exhaust port face each other. Can do.

According to the fifth aspect of the present invention, each head connection port of the damper device and each ink supply port of the recording head are opposed to each other, so that a plurality of inks are respectively absorbed by dynamic pressure and air bubbles are separated to thereby separate the recording head. Each ink supply channel can be supplied.

According to the sixth aspect of the present invention, the plurality of bubble trap chambers are partitioned by the partition wall in the vicinity of one end of the main body case, so that the configuration of the damper device can be simplified even if a plurality of inks are used. .
According to the invention of claim 7, the main body case is composed of an upper case and a lower case, and a plurality of exhaust passages connected to the plurality of exhaust ports are formed in the upper case, so that a plurality of inks are supplied. Even if it is used, the configuration of the damper device can be simplified.

According to the eighth aspect of the invention, a plurality of inks are easily supplied from the ink supply pipe to the end of the damper working chamber via the joint member, and the dynamic pressure is absorbed through the damper working chamber and the bubbles are separated and recorded. It can be supplied to the head.

Next, an embodiment embodying the present invention, described with reference to the drawings.

  As shown in FIG. 1, the ink jet printer of the present invention includes a recording unit 1 that records ink by ejecting ink onto a sheet as a recording medium, inside a main body frame (not shown). The ink jet printer is applied as a printer function of a multi-function device (MFD) having a copy function, a scanner function, a facsimile function, and the like.

  The recording unit 1 is a recording head that constitutes a carriage that reciprocally moves across a horizontally long plate-shaped guide rails 2 and 3 that extend in the Y direction (a direction orthogonal to the paper transport direction X, the main scanning direction). A unit 4, a timing belt 8 disposed in parallel with the upper surface of the guide rail 3 for reciprocating the recording head unit 4, and a CR (carriage) motor 6 for driving the timing belt 8 are provided. .

  As shown in FIGS. 2 and 3, the recording head unit 4 includes a substantially box-shaped main body portion 20a, and a connecting support piece 20b protruding from the main body portion 20a toward the downstream side in the paper conveyance direction (the direction of arrow A in FIG. 1). A head holder 20, an ink jet recording head 21 fixed to the lower surface side of the bottom plate 20c of the head holder 20, and a damper device 10 and an exhaust valve means 11 fixed to the upper side of the bottom plate 20c. Yes.

  The damper device 10 is provided with a connecting piece 13 that extends substantially horizontally on the downstream side of the paper conveyance (in the direction of arrow A in FIG. 1) and is supported by being overlapped with the connecting support piece 20b. (Tube) 14 can be connected at the tip. 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 pipe 14 is connected to the base end of each ink tank. An ink flow path for supplying ink from the ink tank to the recording head 21 via the ink supply pipe 14 and the damper device 10 is formed. In this embodiment, since the ink colors are four colors of black ink (BK), cyan ink (C), yellow ink (Y), and magenta ink (M), there are four ink supply tubes 14, but the ink colors The type of ink and the number of ink supply pipes are not limited to this.

  Further, the upper surfaces of the damper device 10 and the exhaust valve means 11 and the upper surface of the connecting piece 13 of the damper device 10 are covered with lid cover bodies 12 and 13a, respectively (see FIG. 1).

  A number of nozzles 22 are provided on the lower surface of the recording head 21, and in FIG. 8 (view of the recording head 21 seen 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 81 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 81, 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. 3, 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 20c of the head holder 20, and a reinforcing frame 83 is interposed between the recording head 21 and the bottom plate 20c in order to prevent the recording head 21 from being bent at the time of attachment. . A head connection port 41 (described later) of the damper device 10 is inserted into an opening of the bottom plate 20c, and the ink supply port 81 and the head connection port 41 of the damper device 10 are rubberized through an opening provided in the reinforcing frame 83. The seal material 82 such as packing is sandwiched and communicated. In addition, a U-shaped front frame 84 is attached to the nozzle surface (lower surface) side of the recording head 21 to eliminate a step difference in the nozzle surface. A dust capturing filter 62 is attached to the upper surface of each ink supply port 81.

  Next, the configuration of the damper device 10 will be described with reference to FIGS.

  The damper device 10 includes a plurality of ink reservoir chambers 30 that are independent for each ink color, divided by a main partition wall 35 and sub-partition walls 36 and 37 that intersect the main partition wall 35. In the embodiment, a damper working chamber 31 a which is a part of a black ink (BK) ink reservoir chamber 30 is disposed below the main partition wall 35, and the black ink ink reservoir chamber 30 is disposed on the main partition wall 35. The buffer chamber 39, the cyan ink reservoir 30b, the yellow ink reservoir 30c, and the magenta ink reservoir 30d, which are other parts, are arranged in a two-layer structure as a whole. Has been.

  Specifically, the main body case 25 in the damper device 10 includes an upper case 26 having a substantially rectangular shape in plan view, and a substantially box-shaped lower case 27 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 fixed so that the upper case 26 covers the upper surface of the lower case 27. One end in the longitudinal direction of the upper surface portion of the upper case 26 is extended outward to form the connecting piece 13 for connection with the ink supply pipe 14. Both the upper case 26 and the lower case 27 are injection-molded with a synthetic resin material and have rigidity, and the joint portions of both cases 26 and 27 are liquid-tight by ultrasonic welding or the like. (See FIGS. 3, 4, 5, and 6).

  The lower case 27 is provided with an opening on the lower surface thereof that opens most of the area of the lower surface, and the main partition wall 35 is disposed at a position spaced in parallel from the opening and the upper surface of the lower case 27. Is formed. The opening on the lower surface is sealed with a damper flexible film (made of synthetic resin and impermeable to air and liquid) 32. Specifically, the outer peripheral edge of the flexible film 32 is bonded to the lower end surface of the outer peripheral wall 33 that defines the outer periphery of the opening on the lower surface by bonding or ultrasonic welding (FIGS. 9, 11, 12 and 12). (See FIG. 13).

  A damper working chamber 31a, which is a part of the ink reservoir 30a for black ink, is formed flat between the flexible film 32 and the main partition wall 35, and faces the main partition wall 35. That is, the surface sealed with the flexible film 32 is a damper acting surface. Further, as shown in FIG. 9, the damper device 10 is secured between the flexible film 32 and the bottom plate 20c of the head holder 20 with a gap for the deformation of the flexible film 32 secured. The holder 20 is installed so that the damper action surface (flexible film 32) of the black ink damper action chamber 31a is substantially horizontal. The head connection ports 41 a to 41 d connected to the ink supply ports 81 of the recording head 21 are positioned side by side on the lower surface of the lower case 27 so as to face the four ink supply ports 81, and are flexible films. It is opened downward at a position extending below 32 (see FIGS. 5 and 9).

  In the damper working chamber 31a for black ink, an ink inlet 53a to the damper working chamber 31a and an ink outlet 42 from the damper working chamber 31a are formed in the main partition wall 35. Are arranged at positions substantially diagonal in a plan view in the damper working chamber 31a having a substantially rectangular shape in a plan view. The ink outlet 42 has a larger opening area than the ink inlet 53a (see FIGS. 5, 6, and 11).

  A rib 54 projects from the inside of the damper working chamber 31a, and an ink path for guiding ink from the ink inlet 53a to the ink outlet 42 is defined. In the embodiment, the rib 54 has two parallel linear shapes that are integrally projected on the lower surface of the main partition wall 35 and extend in the diagonal direction of the damper working chamber 31a (between the two ribs 54 ( An ink inlet 53a and an ink outlet 42 are arranged on the inner side. Since the hanging length of the rib 54 is formed so as not to reach the flexible film 32, a gap is provided between the tip of the rib 54 and the flexible film 32. Therefore, in the vicinity of the main partition wall 35 serving as the ceiling portion of the damper working chamber 31a, the rib 54 hangs down from the ceiling portion, but in the vicinity of the flexible film 32 serving as the bottom portion of the damper working chamber 31a, the bottom portion Ink is spread throughout (see FIGS. 12 and 13).

  On the upper surface of the main partition wall 35, the sub-partition walls 36 and 37 are formed so as to rise integrally with the main partition wall 35, and a portion above the main partition wall 35 in the lower case 27 is formed. A plurality of ink reservoirs are formed together with the upper case 26.

  In the embodiment, as shown in FIG. 4, two sub-partition walls 36 are disposed so as to extend over the entire length of the lower case 27 with a space therebetween, and together with the side walls of the lower case 27, cyan ink, yellow ink, and Three ink reservoirs 30b to 30d for magenta ink are formed. Each sub partition wall 36 communicates the ink reservoir chambers 30b to 30d with the head connection ports 41b to 41d for each ink color at a position off the upper surface of the main partition wall 35 (see FIG. 9).

  On the other hand, as shown in FIG. 4, the sub partition wall 37 is provided so as to partition the corner portion of the lower case 27 in the vicinity of the head connection port 41 a together with the side wall of the lower case 27 into a substantially triangular shape in plan view. A buffer chamber 39, which is a part of the ink reservoir 30a for black ink, is formed between the sub partition wall 37 and the side wall of the lower case 27. That is, the ink reservoir 30 a for black ink is configured by a damper working chamber 31 a and a buffer chamber 39 that are arranged vertically with the main partition wall 35 as a boundary. As shown in FIG. 12, in the buffer chamber 39, the head connection port 41 a provided at a position separated from the main partition wall 35 and the ink outlet 42 formed in the main partition wall 35 are communicated with each other. ing. Further, the ink outlet 42 communicates the damper working chamber 31 a provided on the lower surface side of the main partition wall 35 with the buffer chamber 39 formed on the upper surface side of the main partition wall 35. Therefore, the ink outlet 42 is an inlet to the buffer chamber 39. The buffer chamber 39 temporarily stores ink therein, and the ceiling surface 61a side formed by the upper case 26 serves as a bubble trapping region 60a so as to gradually accumulate bubbles separated and floated from the ink. . An exhaust port 56a penetrating the upper case 26 is provided in the ceiling surface 61a of the buffer chamber 39 (see FIG. 12).

  The upper case 26 is formed with a plurality of recesses on the upper and lower surfaces thereof, and at the position near the connecting piece 13, three ribs 38 that are continuous in a rectangular ring shape project toward the lower case 27, and this rib 38 The three independent regions are surrounded by (see FIGS. 5 and 5).

  The three regions surrounded by the ribs 38 are formed in a substantially rectangular shape in plan view and open up and down. When the upper case 26 and the lower case 27 are joined, the regions are formed in the lower case 27, respectively. The three ink reservoirs 30b to 30d are accommodated inside (see FIG. 9). The hanging length of the rib 38 is formed so as not to reach the main partition wall 35, and a gap is formed between the tip of the rib 38 and the bottom of each of the ink reservoir chambers 30 b to 30 d, that is, the main partition wall 35. It is comprised so that. The area surrounded by the ribs 38 is a damper that stores a predetermined amount of air in advance in each of the ink reservoirs 30b to 30d for cyan ink, yellow ink, and magenta ink before the start of use of the ink jet printer. The working chambers 31b to 31d are formed. Since the air stored in each of the damper working chambers 31b to 31d is separated from the surroundings by the drooping of the rib 38, the air is not exhausted from the exhaust ports 56b to 56d, 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 (a film made of synthetic resin and impermeable to air and liquid) 43 defines the outer periphery thereof. It joins to the upper end surface of the outer peripheral wall which adhere | attaches by adhesion | attachment or ultrasonic welding.

  In the ink reservoir chambers 30b to 30d for cyan ink, yellow ink, and magenta ink, a bubble trap that gradually accumulates bubbles separated from the damper working chambers 31b to 31d and the ink by the rib 38. The chambers 60b-60d are partitioned, and in the ink reservoir chambers 30b-30d, the damper action chambers 31b-31d are on the ink inlets 53b-53d side, and the bubble trap chambers 60b-60d are the ink outlets. It is provided on the connection ports 41b to 41d side (see FIG. 13). That is, regions on the downstream side of the damper working chambers 31b to 31d (sides close to the head connection ports 41b to 41d) are bubble trap chambers 60b to 60d, respectively. The ceiling surfaces 61b to 61d of the bubble trap chambers 60b to 60d are constituted by the upper case 26, and exhaust ports 56b to 56d penetrating the upper case 26 are formed in the ceiling surfaces 61b to 61d (FIGS. 6 and 6). 12 and FIG. 13).

  The exhaust ports 56a to 56d for black ink, cyan ink, yellow ink, and magenta ink are formed in a shape in which cylindrical portions having cutout portions 63 are suspended from the ceiling surfaces 61a to 61d (FIG. 6, FIG. 6). (See FIG. 12 and FIG. 13). The notch 63 is formed by cutting away the upstream portion of the ink flow in the peripheral portion of the cylindrical portion along the axial direction of the cylindrical portion. The exhaust ports 56a to 56d are arranged in the vicinity of the side wall on the downstream side of the ink flow in the buffer chamber 30 (ink reservoir chamber 30a) and the ink reservoir chambers 30b to 30d, vertically above the head connection ports 41a to 41d. Has been. The paths connecting the exhaust ports 56a to 56d and the head connection ports 41a to 41d are formed in straight shapes having no narrowed portions or bent portions, and the exhaust ports 56a to 41d are connected to the head connection ports 41a to 41d. It is comprised so that the movement of the bubble which floats to 56d may not be prevented.

  As described above, the end of the upper case 26 in the direction of the arrow A is the connecting piece 13, but on one side edge side of the connecting piece 13, the supply pipe connecting port 47 ( In the embodiment, four supply pipe connection ports for black ink, cyan ink, yellow ink, and magenta ink are provided as 47a, 47b, 47c, and 47d, respectively (see FIG. 2 and FIG. 2). 7, FIG. 10 and FIG. 12).

  The ink supply pipes 14 are connected to the supply pipe connection ports 47 through joint members 45 having flow paths for the respective ink colors. Each supply pipe connection port 47 communicates with each ink reservoir chamber 30 through passages provided in the upper case 26 and the lower case 27 (see FIGS. 4, 5, and 6).

  In this embodiment, as shown in FIG. 12, as the ink flow path for black ink, first, the connection piece 13 has a supply pipe connection port 47 a at one end and is opened downward on the lower surface of the connection piece 13. The first concave passage 48a formed in a straight line, the first communication hole 49a formed through the upper and lower surfaces of the connecting piece 13 at the other end of the first concave passage 48a, and the first communication hole 49a A second concave passage 50a formed at the end and opened upward on the upper surface of the connecting piece 13 and formed in an L shape, and the other end of the second concave passage 50a is formed through the upper and lower surfaces of the upper case 26. The second communication hole 51a is provided. On the other hand, as shown in FIG. 4, in the lower case 27, a third communication hole 52 is formed through the corner portion adjacent to the ink reservoir 30d for magenta ink and far from the head connection port 41d. . The lower opening of the third communication hole 52 is provided in the main partition wall 35, and this opening serves as the ink inlet 53a to the above-described black ink damper working chamber 31a. When the upper case 26 and the lower case 27 are joined, the upper end surface of the third passage hole 52 and the lower end surface of the second passage hole 51a are in close contact with each other, whereby the black ink supply pipe is joined. The connection port 47a is connected to the damper working chamber 31a (ink reservoir chamber 30a).

  Further, as shown in FIG. 13, as the ink flow paths for cyan ink, yellow ink, and magenta ink, the connecting piece 13 has supply pipe connection ports 47 b to 47 d at one end, respectively. First concave passages 48b to 48d formed in an L shape by opening downward on the lower surface of 13 and a first through hole formed on the upper and lower surfaces of connecting piece 13 at the other end of first concave passages 48b to 48d. The communication holes 49b to 49d, the second recess passages 50b to 50d each having the first communication holes 49b to 49d at one end and opened upward on the upper surface of the connecting piece 13, and the second recesses Second communication holes 51b to 51d formed through the upper and lower surfaces of the upper case 26 are provided at the other ends of the passages 50b to 50d. The second communication holes 51 b to 51 d are formed by forming a part of the rib 38 in a cylindrical shape and having a center hole thereof, and protrude downward slightly longer than the protruding length of the rib 38. The lower openings of the second communication holes 51b to 51d are ink inlets 53b to 53d to the ink reservoirs 30b to 30d, respectively (see FIGS. 5 and 6). Accordingly, the supply pipe connection ports 47b to 47d for cyan ink, yellow ink, and magenta ink are connected to the respective ink reservoirs 30b to 30d. That is, the ink inlets 53b to 53d and the damper working chambers 31b to 31d are partitioned by a cylindrical wall (a part of the rib 38) surrounding the second communication holes 51b to 51d.

  Further, as described above, the upper case 26 is formed with exhaust ports 56a to 56d communicating with the buffer chamber 39 and the bubble trap chambers 60b to 60d, and the upper ends of the exhaust ports 56a to 56d are formed in the upper case. 26 are respectively connected to a plurality of exhaust passages 57a to 57d which are recessed independently of each other. The exhaust passages 57 a to 57 d extend while being bent in a direction perpendicular to the longitudinal direction of the upper case 26, and the other end is connected to the exhaust valve means 11.

  The first concave passages 48a to 48d formed on the lower surface of the connecting piece 13 are commonly covered by a single film material 44 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. Further, the second concave passages 50a to 50d and the exhaust passages 57a to 57d are extended portions of the damper flexible film 43, and are commonly covered by the same method and formed as flow paths.

  Next, the exhaust valve means 11 will be described. As shown in FIGS. 4B and 5B, the storage portion 70 integrally provided on one side of the lower case 27 has an ink color for each ink color. Four passage holes 71 are formed so as to be long in the vertical direction and open vertically. The side edge of the upper case 26 is extended to a position that covers the upper end of the storage portion 70, and the openings 58 at the other ends of the exhaust passages 57 a to 57 d are individually communicated with the upper ends of the passage holes 71. . A valve body (not shown) is accommodated in each passage hole 71 and is driven so as to open and close the lower end opening of the passage hole 71. When the carriage (recording head unit 4) moves to the position of a maintenance unit (not shown) in the ink jet printer, the valve element is driven to open the lower end opening of the passage hole 71 and the lower end opening is sucked by the suction pump. The As a result, the bubbles in the ink reservoirs 30 a to 30 d can be exhausted through the exhaust ports 56 a to 56 d and the exhaust passage 57.

  According to the above configuration, first, ink in an ink tank (not shown) is supplied to the damper device 10 from the supply pipe connection port 47 through the ink supply pipe 14. As shown in FIG. 12, the black ink passes from the supply pipe connection port 47a through the first concave passage 48a and the second concave passage 50a of the connecting piece 13 to the lower surface side of the main partition wall 35 from the ink inlet 53a. It flows into the damper working chamber 31a. The dynamic pressure of the ink propagated from the ink inlet 53a directly hits the flexible film 32 (damper action surface) facing the ink inlet 53a. At this time, the ink spreads over the entire bottom of the damper action chamber 31a. The dynamic pressure is reliably absorbed (damped) over a wide area. Then, the black ink, along with the bubbles, is guided to the ink outlet 42 by the ribs 54 suspended from the ceiling of the damper working chamber 31a, and is quickly discharged from the ink outlet 42 having a wide opening area.

  The black ink flowing out from the ink outlet 42 flows into a buffer chamber 39 formed on the upper side of the main partition wall 35. Since the buffer chamber 39 is disposed above the damper working chamber 31a, the bubbles rise without flowing and flow into the buffer chamber 39. In the buffer chamber 39, the ink supplied to the recording head 21 is temporarily stored, and the bubbles separated and floated from the ink are gradually accumulated in the bubble trap region 60a. Then, black ink is supplied from the head connection port 41 a provided at the bottom of the buffer chamber 39 to the ink supply port 81 for black ink of the recording head 21.

  On the other hand, as shown in FIG. 13, the cyan ink, the yellow ink, and the magenta ink flow from the supply pipe connection ports 47b to 47d through the first concave passages 48b to 48d and the second concave passages 50b to 50d, respectively. The ink flows into the ink reservoirs 30b to 30d from the inlets 53b to 53d. In the ink reservoir chambers 30b to 30d, damper working chambers 31b to 31d, in which a certain amount of air is stored in advance and the ceiling portion thereof is covered with the flexible film 43, are arranged on the upstream side in the ink reservoir chambers 30b to 30d. The dynamic pressure of the ink is immediately absorbed (damped) by the flexible film 43 and the air. Then, the ink flows downstream through the bottom surfaces of the ink reservoirs 30b to 30d, and the bubbles contained in the ink are separated and floated and gradually accumulated in the bubble trap chambers 60b to 60d. Note that air bubbles may be separated from the ink in the vertically lower portions of the damper working chambers 31b to 31d (the bottom side of the hanging rib 38), but the damper working chambers 31b to 31d are filled with air. Therefore, the separated bubbles are accumulated in the bubble trap chambers 60b to 60d so as to overflow from the damper working chamber.

  12 and 13, in the buffer chamber 39 and the ink reservoir chambers 30b to 30d for black ink, cyan ink, yellow ink, and magenta ink, when ink flows into the recording head 21, bubbles are generated in the filter 62. The air bubbles are not hindered from rising even if they are caught, so that they are quickly raised and accumulated in the air bubble trap region 60a and the air bubble trap chambers 60b to 60d provided vertically above the head connection ports 41a to 41d.

  When the carriage 5 moves to the maintenance position and the exhaust valve means 11 is connected to the suction pump as a bubble removal maintenance operation, the bubbles accumulated in the buffer chamber 39 and the bubble trap chambers 60b to 60d are respectively The exhaust ports 56a to 56d are exhausted to the outside through the exhaust passages 57a to 57d and the exhaust valve means 11.

  Thus, in the above configuration, each bubble trap region 60a and bubble trap chambers 60b to 60d are arranged vertically above the corresponding head connection ports 41a to 41d, and the path connecting them is configured straight. Yes. For this reason, even if a bubble is caught by the filter 62 provided below the head connection ports 41a to 41d, the bubble is not prevented from rising, so that it quickly rises to the bubble trap region 60a and the bubble trap chambers 60b to 60d. Accumulated. As a result, the head connection ports 41a to 41d can be prevented from being blocked by bubbles, and ink supply to the recording head 21 can be performed without delay.

  Further, each of the damper working chambers 31b to 31d for cyan ink, yellow ink, and magenta ink has a very simple structure in which the rib 38 is suspended, and a certain amount of air defined by the length of the rib 38 is reliably ensured. Can be stored. Furthermore, since the ceiling surfaces of the damper working chambers 31 b to 31 d are covered with the flexible film 43, a high damper effect can always be stably exhibited by the cooperation of the bubbles and the flexible film 43.

  Further, in the above embodiment, the exhaust ports 56a to 56d are provided in the vicinity of the side wall on the downstream side of the ink flow so that the bubbles accumulated in the bubble trap region 60a and the bubble trap chambers 60b to 60d can be efficiently removed by the maintenance operation. By exhausting, a large amount of ink can be stored in the ink reservoir.

  In the above-described embodiment, the damper working chambers 31b to 31d are configured by surrounding the periphery thereof with an annular rib 33. However, the damper working chambers 31b to 31d are suspended from the ceiling between the damper working chamber and the bubble trap chamber. Further, by providing a wall with a gap between the bottom and the bottom, a certain amount of air may be stored. Further, when the ink inlet to the ink reservoir is provided on the ceiling surface side of the side wall of the ink reservoir, for example, the ink inlet is suspended from the ceiling between the damper working chamber and the ink inlet. You may comprise so that a fixed quantity of air may be stored by providing the wall which provided the gap | interval between the bottom part.

FIG. 3 is a perspective view of a recording unit in the ink jet printer according to the embodiment of the present invention. It is a perspective view of a recording head unit. FIG. 3 is an exploded perspective view of a recording head unit. (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. It is a top view of the state recording head unit except the flexible film | membrane 43 of a damper apparatus. It is a bottom view of the recording head unit. It is the IX-IX arrow directional cross-sectional view of FIG. 7 in the state which excluded the flexible film | membrane 43 of the damper apparatus. It is a top view of the state which removed the flexible film | membrane 43 of the damper apparatus. It is a bottom view of the state which removed the flexible film | membrane 32 of the damper apparatus. FIG. 11 is a cross-sectional view taken along line XII-XII in FIG. 10 with the flexible films 32 and 43 of the damper device attached. FIG. 11 is a cross-sectional view taken along line XIII-XIII in FIG. 10 with the flexible films 32 and 43 of the damper device attached.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Recording part 4 Recording head unit 10 Damper device 11 Exhaust valve means 14 Ink supply pipe 20 Head holder 21 Recording head 22 Nozzle 23 Actuator 24 Flexible flat cable 26 Upper case 27 Lower case 30 Ink reservoir chamber 31 Damper action chamber 32 Flexibility Membrane 35 Main partition wall 36 Subpartition wall 37 Subpartition wall 38 Rib 39 Buffer chamber 41 Head connection port 43 Flexible membrane 47 Supply pipe connection port 54 Rib 56 Exhaust port 57 Exhaust passage 60a Bubble trap regions 60b-60d Bubble trap chamber 62 Filter 63 Notch 81 Ink supply port

Claims (8)

An ink jet recording head is mounted on a carriage that moves relative to a recording medium, and an ink is supplied to the recording head from an ink supply source mounted on the main body via an ink supply tube and a damper device mounted on the carriage. In an inkjet printer configured to supply
The damper device, e Bei ink reservoir chamber having a damper working chamber to absorb the dynamic pressure of the ink that has flowed, and a bubble trap chamber bubbles to accumulate in the ink from the ink supply pipe,
The ink reservoir chamber is connected to a head connection port that supplies ink in the ink reservoir chamber to the recording head substantially vertically below the bubble trap chamber, and the head connection is provided on the ceiling surface of the bubble trap chamber. Connected to an exhaust port that is located substantially vertically above the mouth and can discharge the bubbles in the bubble trap chamber to the outside,
The ink reservoir chamber extends laterally with respect to the substantially vertical direction in which the head connection port and the exhaust port face each other, has the damper action chamber at a position away from the bubble trap chamber, and the damper inkjet printer, wherein the working chamber, that you have connected to the ink inlet port for receiving ink from the ink supply pipe at the opposite side to the bubble trap chamber. An ink jet recording head is mounted on a carriage that moves relative to a recording medium, and a damper device mounted on the carriage is supplied with ink from a plurality of ink supply sources mounted on the main body via an ink supply pipe. In an inkjet printer configured to be supplied to the recording head via,
The damper device includes, for each ink, an ink reservoir chamber having a damper working chamber that absorbs dynamic pressure of ink flowing from the ink supply pipe and a bubble trap chamber that accumulates bubbles contained in the ink.
The ink reservoir chamber is connected to a head connection port that supplies ink in the ink reservoir chamber to the recording head substantially vertically below the bubble trap chamber, and the head connection is provided on the ceiling surface of the bubble trap chamber. A set of the bubble trap chamber and the head connection port of one ink reservoir chamber is connected to an exhaust port that is positioned substantially vertically above the port and capable of discharging the bubbles in the bubble trap chamber to the outside. The substantially vertical direction is positioned parallel to each other with respect to the set of the bubble trap chamber and the head connection port of the ink reservoir,
The ink reservoir chamber extends laterally with respect to the substantially vertical direction in which the head connection port and the exhaust port face each other, has the damper action chamber at a position away from the bubble trap chamber, and the damper The working chamber is connected to an ink inlet that receives ink from the ink supply pipe on the side opposite to the bubble trap chamber, and the plurality of damper working chambers are arranged in a direction from the ink inlet to the bubble trap chamber. features and to Louis inkjet printers that are parallel. The damper action chamber, the claims from the ink inlet, the head connecting port and said exhaust port, characterized in that it is sealed by a flexible membrane surface parallel to the direction toward the position opposite The inkjet printer according to 1 or 2. The damper operation chamber is connected to the bubble trap chamber so as to supply ink from a position lower than the ceiling surface to a position where the head connection port and the exhaust port face each other. Item 4. The inkjet printer according to any one of Items 1 to 3. The recording head has a plurality of ink supply ports connected to a plurality of ink supply channels,
The ink jet printer according to claim 2 , wherein the damper device has the head connection ports corresponding to the plurality of ink supply ports arranged side by side on an end bottom surface . The damper device has a main body case,
6. The ink jet printer according to claim 5 , wherein the plurality of bubble trap chambers are partitioned from each other by a partition wall in the vicinity of one end of the main body case . The main body case includes an upper case having the ceiling surface and the plurality of exhaust ports, and a lower case having the plurality of head connection ports, and the upper case is connected to the plurality of exhaust ports. The inkjet printer according to claim 6, further comprising a passage. The plurality of damper working chambers are formed to extend from the one end side to the other end side of the main body case,
A plurality of passages extend from a joint member connected to each of the ink supply pipes and having a flow path for each ink. The front ends of the passages serve as the ink inlets, and are connected to the end of the damper working chamber on the other end side The ink jet printer according to claim 6.