JP2022125975A - Head unit, recording head, and inkjet recording device having the same - Google Patents

Abstract

To provide a head unit which can suppress liquid leakage from a connection part at the time of replacement of a recording head with a simple configuration, a recording head, and an inkjet recording device having the same.SOLUTION: A head unit includes a common flow channel, one or more recording heads, and a joint mechanism. The joint mechanism has a first opening/closing valve for opening/closing a liquid supply path, and connects the common flow channel and the recording heads. The first opening/closing valve has a switching member having an insertion hole and an engagement boss projected on the inner peripheral surface of the insertion hole, a first opening/closing member having a sliding part which is inserted to the insertion hole so as to be vertically slidable and an engagement groove with which the engagement boss is engaged, and a first sealing member which is mounted on the first opening/closing member and comes into contact with or separates from the inner peripheral surface of the insertion hole. By rotating the switching member and vertically moving the first opening/closing member, the first opening/closing valve is switched between a close state where the first sealing member comes in contact with the inner peripheral surface of the insertion hole and an open state where the first sealing member separates from the inner peripheral surface of the insertion hole.SELECTED DRAWING: Figure 9

Description

1. Field of the Invention The present invention relates to a head unit and a printhead mounted in an inkjet printing apparatus, and an inkjet printing apparatus having the same, and more particularly to a structure for attaching the printhead to the head unit.

2. Description of the Related Art Conventionally, in an inkjet recording apparatus such as an inkjet printer, ink is ejected from ink ejection nozzles provided in a recording head, and the ejected ink adheres to a recording medium such as paper to form dots. In the ink jet recording apparatus as described above, it is conceivable that some of the ink ejection nozzles may become difficult to eject ink due to clogging or the like. In this case, it is necessary to replace the recording head.

In a so-called line head type printer in which the recording head is arranged so that the ink ejection nozzles are arranged over the entire width of the recording medium, for example, if three recording heads are unitized for one color, Replacing the entire head unit is relatively easy. The reason for this is that one head unit completes the flow paths of liquid such as ink and cleaning liquid.

However, since in most cases only one recording head fails in the head unit, replacing the entire head unit will cost extra. Therefore, it is desirable to replace only the failed recording head. However, when replacing only one print head, it is necessary to block the liquid flow path, and there is concern about liquid leakage during replacement.

As a method for avoiding liquid leakage when replacing a recording head, for example, Patent Document 1 discloses an ink jet printer that detachably holds an ink tank containing ink. Inkjet recording apparatus that avoids ink leakage during maintenance such as head replacement by increasing the negative pressure of the printer and stopping the negative pressure increase by the negative pressure increasing mechanism by installing it in the printer. disclosed.

Further, in Japanese Patent Laid-Open No. 2002-100002, an on-off valve for opening and closing an ink supply path is provided on a carriage on which a recording head is mounted. An ink jet recording apparatus is disclosed in which an on-off valve is opened when the recording head is connected to the head, and the on-off valve is closed when the recording head is separated.

JP-A-2002-36586 JP 2006-68994 A

In the method of Patent Document 1, it is necessary to provide a negative pressure increasing mechanism in the head cartridge, which complicates the structure and increases the cost. In addition, in the configuration of Patent Document 1, the ink tank is arranged in the head cartridge, but it cannot be applied to the configuration in which the ink tank is arranged separately from the print head. In addition, in the configuration of Patent Document 2, since the supply valve is not opened or closed unless the head fixing lever is operated, there is a possibility of forgetting to operate the head fixing lever or of ink leakage during the time until the head fixing lever is operated. was there.

SUMMARY OF THE INVENTION In view of the above problems, it is an object of the present invention to provide a head unit, a print head, and an ink jet printing apparatus having the same that can suppress liquid leakage from a connection portion at the time of replacement of the print head with a simple configuration. and

In order to achieve the above object, a first configuration of the present invention includes a common flow path, one or more recording heads, and a joint mechanism, and is mounted in an inkjet recording apparatus to record an image on a recording medium. is the head unit. The common channel has a liquid supply channel through which one or more liquids including ink pass. The print head is attachable to and detachable from the common flow path, and has a plurality of nozzles for ejecting ink. The joint mechanism has a first on-off valve that opens and closes the liquid supply path, and connects the liquid supply path and the recording head. The first opening/closing valve has a switching member, a first opening/closing member, and a first sealing member. The switching member has an insertion hole and an engagement boss projecting from the inner peripheral surface of the insertion hole. The first opening/closing member includes a sliding portion that is vertically slidably inserted into the insertion hole, and an engaging groove that is formed to be inclined with respect to an axial direction of the sliding portion and engages with the engaging boss. and have The first sealing member is attached to the first opening/closing member and contacts or separates from the inner peripheral surface of the insertion hole. By rotating the switching member to move the first opening/closing member up and down, the first opening/closing valve is brought into a closed state in which the first sealing member is in contact with the inner peripheral surface of the insertion hole, and a closed state in which the first sealing member is inserted. and an open state away from the inner peripheral surface of the hole.

According to the first configuration of the present invention, by rotating the switching member of the first on-off valve to move the first on-off member up and down, the first sealing member attached to the first on-off member is inserted into the switching member. It can be switched between a closed state in which it is in contact with the inner peripheral surface of the hole and an open state in which it is separated from the inner peripheral surface of the insertion hole. Therefore, it is possible to open and close the liquid supply path with a simple structure, and it is possible to suppress liquid leakage from the connecting portion when the recording head is replaced.

FIG. 1 is an explanatory diagram showing a schematic configuration of a printer 100 as an inkjet recording apparatus according to one embodiment of the present invention; Plan view of recording unit 9 provided in printer 100 Side view of recording heads 17a to 17c constituting line heads 11Y to 11K of recording unit 9 A plan view of the recording heads 17a to 17c viewed from the ink ejection surface F side. Schematic diagram showing the internal structure of the ink supply path 40a, the cleaning liquid supply path 40b, and the recording heads 17a to 17c that constitute the line head 11Y of the printer 100. A side view of the head unit 51 viewed from the upstream side in the paper transport direction. Plan view of the head unit 51 viewed from above Partially enlarged view of the vicinity of the recording head 17b of the head unit 51 Side cross-sectional view of joint mechanism 60a of recording head 17b A perspective view showing a state in which the first on-off valve 61 is attached to the common flow path 40. A perspective view of a switching member 62 that constitutes the first on-off valve 61. A perspective view of a first opening/closing member 63 that constitutes the first opening/closing valve 61. 4 is a perspective view showing a state in which the guide groove 63e of the first opening/closing member 63 is engaged with the rotation restricting rib 81; FIG. A perspective view of the connecting member 65 FIG. 4 is a side cross-sectional view of the joint mechanism 60a showing a state in which the first on-off valve 61 and the second on-off valve 67 are closed; FIG. 4 is a side cross-sectional view of the joint mechanism 60a showing a state in which the first on-off valve 61 and the second on-off valve 67 are opened; An enlarged view of the vicinity of the joint mechanism 60a on the side surface of the recording head 17b, showing a state in which the joint mechanism 60a is connected. FIG. 18 is an enlarged view of the vicinity of the joint mechanism 60a on the side surface of the recording head 17b, showing a state in which the connecting member 65 has been moved to the retracted position from the state of FIG. 17; FIG. 18 is an enlarged perspective view of a gap portion between the first on-off valve 61 and the connecting member 65 in FIG. Schematic diagram showing the internal structure of the ink supply path 40a, the cleaning liquid supply path 40b, and the recording heads 117a to 117c that constitute the line head 11Y of the printer 100. Side cross-sectional view of joint mechanism 160a in FIG.

[1. Configuration of Inkjet Recording Apparatus]
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory diagram showing a schematic configuration of a printer 100 as an inkjet recording apparatus according to one embodiment of the invention. The printer 100 includes a paper feed cassette 2 that is a paper storage unit. The paper feed cassette 2 is arranged in the lower part of the printer main body 1 . Paper P, which is an example of a recording medium, is accommodated inside the paper feed cassette 2 .

A paper feeding device 3 is arranged on the downstream side of the paper feeding cassette 2 in the paper conveying direction, that is, above the right side of the paper feeding cassette 2 in FIG. The paper feeder 3 separates and feeds the paper P one by one toward the upper right side of the paper feed cassette 2 in FIG.

The printer 100 has a first paper transport path 4a inside. The first paper transport path 4a is positioned on the upper right side of the paper feed cassette 2 in the paper feed direction. The paper P sent out from the paper feed cassette 2 is transported vertically upward along the side surface of the printer body 1 by the first paper transport path 4a.

A registration roller pair 13 is provided at the downstream end of the first paper transport path 4a in the paper transport direction. Furthermore, the first conveying unit 5 and the recording section 9 are arranged immediately downstream of the registration roller pair 13 in the sheet conveying direction. The paper P sent out from the paper feed cassette 2 reaches the registration roller pair 13 through the first paper transport path 4a. The pair of registration rollers 13 corrects skewed feeding of the paper P, measures the timing with the ink ejection operation executed by the recording unit 9, and directs the paper toward the first conveying unit 5 (especially the first conveying belt 8 described later). Send out P.

The paper P sent to the first transport unit 5 by the pair of registration rollers 13 is transported by the first transport belt 8 to a position facing the recording section 9 (especially recording heads 17a to 17c, which will be described later). An image is recorded on the paper P by ejecting ink onto the paper P from the recording unit 9 . At this time, ejection of ink in the recording unit 9 is controlled by the control device 110 inside the printer 100 .

A second transport unit 12 is arranged downstream of the first transport unit 5 (left side in FIG. 1) in the paper transport direction. The paper P on which the image is recorded by the recording section 9 is sent to the second transport unit 12 . The ink ejected onto the surface of the paper P is dried while passing through the second transport unit 12 .

A decurler section 14 is provided in the vicinity of the left side of the printer main body 1 on the downstream side of the second transport unit 12 in the paper transport direction. The paper P, the ink of which has been dried by the second transport unit 12, is sent to the decurler section 14, where the curl of the paper P is corrected.

A second paper transport path 4b is provided downstream of the decurler section 14 (upper in FIG. 1) in the paper transport direction. The paper P that has passed through the decurler section 14 passes through the second paper transport path 4b and is discharged to a paper discharge tray 15a provided outside the left side of the printer 100 when double-sided recording is not performed. Below the paper ejection tray 15a, a sub-ejection tray 15b is provided for ejecting unnecessary paper P (waste paper) having printing defects or the like.

A reversing transport path 16 for double-sided recording is provided above the printer main body 1 and above the recording section 9 and the second transport unit 12 . When performing double-sided recording, the paper P that has completed recording on one side (first side) of the paper P and has passed through the second conveying unit 12 and the decurler section 14 passes through the second paper conveying path 4b and is reversed. It is sent to the transport path 16 .

The transport direction of the paper P sent to the reverse transport path 16 is switched so that the other surface (second surface) of the paper P is subsequently recorded. Then, the paper P passes through the upper portion of the printer main body 1, is sent rightward, passes through the pair of registration rollers 13, and is sent again to the first transport unit 5 with the second surface facing upward. In the first transport unit 5 , the paper P is transported to a position facing the recording section 9 , and an image is recorded on the second surface by ink ejection from the recording section 9 . After double-sided recording, the paper P passes through the second transport unit 12, the decurler section 14, and the second paper transport path 4b in order, and is discharged to the paper discharge tray 15a.

A maintenance unit 19 and a cap unit 20 are arranged below the second transport unit 12 . The maintenance unit 19 moves horizontally below the recording section 9 when purging is performed, wipes off the ink ejected from the ink ejection openings of the recording head, and recovers the wiped-off ink. Note that purging refers to an operation of forcibly pushing out ink from the ink ejection openings of the print head in order to discharge thickened ink, foreign matter, and air bubbles in the ink ejection openings. The cap unit 20 moves horizontally below the recording section 9 when capping the ink ejection surface of the recording head, and then moves upward to be attached to the lower surface of the recording head.

FIG. 2 is a plan view of the recording section 9. As shown in FIG. The recording unit 9 includes a head housing 10 and line heads 11Y, 11M, 11C, and 11K. The line heads 11Y to 11K are arranged on a conveying surface of an endless first conveying belt 8 stretched over a plurality of rollers including a driving roller 6a, a driven roller 6b, and a tension roller (not shown). It is held in the head housing 10 at a height that forms a gap (for example, 1 mm). The drive roller 6a causes the first transport belt 8 to run in the transport direction of the paper P (arrow A direction).

The line heads 11Y to 11K each have a plurality (here, three) of recording heads 17a to 17c. The recording heads 17a to 17c are arranged in a zigzag pattern along the paper width direction (arrow BB' direction) perpendicular to the paper transport direction (arrow A direction). The recording heads 17a to 17c have a plurality of ink ejection openings 18 (nozzles). The ink discharge ports 18 are arranged at regular intervals in the width direction of the recording head, that is, in the paper width direction (arrow BB' direction). From the line heads 11Y to 11K, yellow (Y), magenta (M), cyan (C), and black (K) inks are first conveyed through the ink ejection ports 18 of the recording heads 17a to 17c. Each ink is discharged toward the paper P conveyed by the belt 8 .

3 is a side view of the recording heads 17a to 17c constituting the line heads 11Y to 11K of the recording section 9, and FIG. 4 is a plan view of the recording heads 17a to 17c viewed from the ink ejection surface F1 side. Since the recording heads 17a to 17c have the same shape and configuration, the recording heads 17a to 17c are shown as one figure in FIGS. As shown in FIGS. 3 and 4, the ink ejection surfaces (nozzle surfaces) F1 of the recording heads 17a to 17c are provided with a plurality of nozzles (here, four blocks) in which a large number of ink ejection openings 18 (see FIG. 2) are arranged. Regions Ra to Rd are provided. The ink ejection surface F1 is made of, for example, SUS (stainless steel).

The recording heads 17a to 17c constituting the line heads 11C to 11K are supplied with ink of four colors (cyan, magenta, yellow and black) from the liquid supply mechanism 50 (see FIG. 5) for each color of the line heads 11C to 11K. supplied to

Each of the recording heads 17a to 17c is driven by a control signal from the control device 110 (see FIG. 1), in accordance with image data received from an external computer. Ink is ejected from the ink ejection port 18 toward P. As a result, a color image is formed on the paper P on the first conveying belt 8 by superimposing the four colors of cyan, magenta, yellow, and black inks. A cleaning liquid supply unit 30 for supplying cleaning liquid is provided at one end of the recording heads 17a to 17c in the longitudinal direction (direction of arrow BB') perpendicular to the paper transport direction (direction of arrow A). The cleaning liquid supply portion 30 is formed with a large number of cleaning liquid supply ports 30a.

In the printer 100, in order to clean the ink ejection surfaces F1 of the recording heads 17a to 17c, the ink ejection ports 18 of all the recording heads 17a to 17c are cleaned at the start of printing after a long period of stoppage and between printing operations. A recording head that pushes out (purges) ink, supplies cleaning liquid from a cleaning liquid supply port 30a to a cleaning liquid supply surface F2, and wipes the ink ejected onto the ink ejection surface F1 with a wiper (not shown) together with the cleaning liquid. Recovery operations 17a to 17c are executed to prepare for the next printing operation. The ink and cleaning liquid wiped off from the ink ejection surface F1 are collected by an ink receiver (not shown).

FIG. 5 is a schematic diagram showing the internal structure of the ink supply path 40a, the cleaning liquid supply path 40b, and the recording heads 17a to 17c that constitute the line head 11Y of the printer 100. As shown in FIG. Note that the line heads 11M to 11K have exactly the same configuration, so description thereof will be omitted. Since the internal structures of the recording heads 17a to 17c are the same, only the internal structure of the recording head 17a is shown in FIG.

As shown in FIG. 5, a common flow path 40 through which ink and cleaning liquid pass is connected to the recording heads 17a to 17c. In the common flow path 40, two ink supply paths 40a through which ink passes and one cleaning liquid supply path 40b through which cleaning liquid passes are formed. The upstream ends of the ink supply path 40 a and the cleaning liquid supply path 40 b are connected to the liquid supply mechanism 50 . The liquid supply mechanism 50 includes a tank containing ink and cleaning liquid, and a pump (both not shown) for pumping up the ink and cleaning liquid from the tank.

The two ink supply paths 40a are branched into a total of six paths, three paths each at the downstream end, and two paths are connected to the ink discharge ports 18 of the recording heads 17a to 17c. The cleaning liquid supply path 40b branches into three paths at the downstream end, and is connected to the cleaning liquid supply section 30 (see FIGS. 3 and 4) of the recording heads 17a to 17c. A unit including the recording heads 17a to 17c and the common flow path 40 is hereinafter referred to as a head unit 51 (see FIG. 6).

Each of the recording heads 17a to 17c has a head front portion 41, a head rear portion 43, and a heater . The head front portion 41 is provided with an ink ejection surface F1 on which a large number of ink ejection ports 18 are arranged, and a cleaning liquid supply portion 30 (both of which are shown in FIG. 4) for supplying the cleaning liquid.

The head rear surface portion 43 includes an ink heating channel 45 , a filter 46 , a reservoir tank 47 and a damper 48 . The ink supply path 40 a passes through the ink heating path 45 , the filter 46 , the reservoir tank 47 and the damper 48 in order, and is connected to the ink ejection port 18 of the head front portion 41 .

A heater 44 is arranged between the head front portion 41 and the head rear portion 43 . The heater 44 heats the ink in the ink heating flow path 45 described later to a predetermined temperature as needed, and also heats the head front portion 41 so that the ink is smoothly ejected from the ink ejection port 18 . do.

The ink heating channel 45 heats the ink in the ink supply channel 40a to a predetermined temperature. The ink heating flow path 45 is provided at a position adjacent to the heater 49 within the head back surface portion 43 . The filter 46 removes foreign matter from the ink passing through the ink supply path 40a. The reservoir tank 47 temporarily stores ink passing through the ink supply path 40a. The damper 48 is formed of a flexible resin film, and pulsating the damper 48 pushes the ink out to the head front portion 41 .

One of the two ink supply paths 40a is used to supply ink from the liquid supply mechanism 50 to the recording heads 17a to 17c, and the other is used to collect ink from the recording heads 17a to 17c to the liquid supply mechanism 50. . When printing an image with a large amount of ink ejected, both of the two ink supply paths 40a can be used to supply ink to the printheads 17a to 17c.

FIG. 6 is a side view of the head unit 51 viewed from the upstream side (right side in FIG. 2) in the paper transport direction. FIG. 7 is a plan view of the head unit 51 viewed from above. FIG. 8 is a partially enlarged view of the vicinity of the recording head 17b of the head unit 51. As shown in FIG. The recording heads 17a to 17c can be attached to and detached from the common flow path 40 individually. More specifically, the three joint mechanisms 60a to 60c connecting the recording heads 17a to 17c and the common flow path 40 are connected to the common flow path by three (total of nine) first fixing screws 55 per location. 40 is fastened from above. Both left and right ends of each of the recording heads 17 a to 17 c are fastened to the common flow path 40 with second fixing screws 57 . A radiator plate 53 is attached to the side surface of each of the recording heads 17a to 17c. The radiator plate 53 radiates heat generated from a flexible substrate (not shown) arranged inside.

The joint mechanism 60a and the joint mechanism 60b are each connected to two ink supply paths 40a (see FIG. 7). The joint mechanism 60c is connected to the cleaning liquid supply path 40b.

[2. Configuration of joint mechanism]
A detailed configuration of the joint mechanisms 60a to 60c will be described below. FIG. 9 is a side sectional view of the joint mechanism 60a of the recording head 17b. FIG. 10 is a perspective view showing a state in which the first on-off valve 61 is attached to the common flow path 40. FIG. FIG. 11 is a perspective view of a switching member 62 that constitutes the first on-off valve 61. As shown in FIG. FIG. 12 is a perspective view of the first opening/closing member 63 that constitutes the first opening/closing valve 61. As shown in FIG. 13 is a perspective view showing a state where the guide groove 63e of the first opening/closing member 63 is engaged with the rotation restricting rib 81. FIG. 14 is a perspective view of the connecting member 65. FIG. Although the configuration of the joint mechanism 60a of the recording head 17b is illustrated here, the joint mechanisms 60b and 60c also have the same configuration as the joint mechanism 60a. The joint mechanisms 60a to 60c of the recording heads 17a and 17c also have the same configuration.

As shown in FIG. 9, the joint mechanism 60a includes a first on-off valve 61, a connecting member 65, and a second on-off valve 67. As shown in FIG. The first on-off valve 61 is attached to the ends of the ink supply path 40a and the cleaning liquid supply path 40b (see FIG. 7) of the common flow path 40. As shown in FIG. The first opening/closing valve 61 has a switching member 62 and a first opening/closing member 63 .

As shown in FIG. 11, the switching member 62 has a hollow, substantially cylindrical shape whose diameter gradually decreases upward, and has an insertion hole 62a into which the first opening/closing member 63 is inserted. An engaging boss 62b protrudes from the inner peripheral surface of the insertion hole 62a. A first flange portion 62c, a second flange portion 62d, and a lever portion 62e are formed on the outer peripheral surface of the switching member 62. As shown in FIG. A first O-ring 80a (see FIG. 9) that seals the gap between the common flow path 40 and the switching member 62 is attached to the first flange portion 62c. A second O-ring 80b (see FIG. 9) that seals the gap between the first on-off valve 61 and the connecting member 65 is attached to the second flange portion 62d. The lever portion 62 e is pressed in the circumferential direction when the switching member 62 is rotated to open and close the first on-off valve 61 .

An engaging claw 62f is formed at the upper end of the switching member 62. As shown in FIG. The engaging claw 62f engages with the engaged portion 40c (see FIG. 9) in the common flow path 40, so that as shown in FIG. Prevent falling.

As shown in FIG. 12, the first opening/closing member 63 has a sliding portion 63a, a pressing portion 63b, and a small diameter portion 63c. The sliding portion 63a has a substantially cylindrical shape and is inserted into the insertion hole 62a of the switching member 62 so as to be vertically slidable. An engaging groove 63d and a guide groove 63e are formed on the outer surface of the sliding portion 63a. The engagement groove 63d is formed so as to be inclined with respect to the axial direction (vertical direction) of the sliding portion 63a, and the engagement boss 62b (see FIG. 11) of the switching member 62 is engaged. The guide groove 63e is formed parallel to the axial direction (vertical direction) at a position facing the engaging groove 63d of the sliding portion 63a.

13 is a perspective view showing a state where the guide groove 63e of the first opening/closing member 63 is engaged with the rotation restricting rib 81. FIG. A rotation restricting rib 81 protrudes from the lower surface of the common flow path 40 (see FIG. 10). A guide groove 63 e of the member 63 engages with the rotation restricting rib 81 .

The pressing portion 63b is provided at the lower end portion of the first opening/closing member 63 and contacts the tip portion 68a (see FIG. 15) of the second opening/closing member 68. As shown in FIG. The small diameter portion 63c is formed between the sliding portion 63a and the pressing portion 63b, and is in contact with the inner surface of the insertion hole 62a of the switching member 62 when the first on-off valve 61 is closed. 9, first sealing member) is attached.

As shown in FIG. 14, the connecting member 65 includes a hollow cylindrical main body 65a with open upper and lower ends, and a support plate fixed in the vicinity of the upper end of the main body 65a in a horizontal direction orthogonal to the axial direction. 65b. An upper end portion of the body portion 65a is connected to the first on-off valve 61 (see FIG. 9). A lower end portion of the main body portion 65a is connected to an ink supply port 70 (see FIG. 9) of the recording head 17b.

A liquid passage port 65c is formed in the vicinity of the upper end portion of the body portion 65a. A second on-off valve 67 (see FIG. 9) is arranged inside the body portion 65a. The second opening/closing valve 67 has a second opening/closing member 68 and a coil spring 69 that biases the second opening/closing member 68 upward. The liquid passage port 65 c has a smaller inner diameter than other portions of the main body 65 a , and closes the ink flow path in the connecting member 65 when the second opening/closing member 68 is pressed by the biasing force of the coil spring 69 . A fourth O-ring 80d (see FIG. 9, second sealing member) is attached to the second opening/closing member 68 so as to be in contact with the periphery of the liquid passage port 65c.

A tip portion 68 a of the second opening/closing member 68 protrudes upward from the liquid passage port 65 c of the connecting member 65 and contacts the pressing portion 63 b of the first opening/closing member 63 . A lower end portion of the coil spring 69 is fixed to a spring receiving portion 70a formed in an ink supply port 70 of the recording head 17b. A fifth O-ring 80 e (see FIG. 9 ) is attached to the ink supply port 70 to seal the gap between the connecting member 65 and the ink supply port 70 .

Screw holes 65d into which the first fixing screws 55 are fastened are formed at three locations on the upper surface of the body portion 65a. By fastening the first fixing screw 55 to the screw hole 65d, the connecting member 65 is fixed at the position (connecting position) where it is connected to the first on-off valve 61 as shown in FIG.

A liquid reservoir 73 is formed between the upper surface of the main body 65a and the liquid passage port 65c. As shown in FIG. 9, the liquid storage portion 73 has a larger diameter than the portion below the liquid passage port 65c, and is equal to or larger than the space between the first on-off valve 61 and the second on-off valve 67. has a volume of Projections 71 are formed on the side ends of the support plate 65b. The protrusion 71 protrudes to the outside from an opening 53a (see FIG. 17) formed in the radiator plate 53. As shown in FIG.

Next, opening and closing operations of the first on-off valve 61 and the second on-off valve 67 will be described. 15 and 16 are side cross-sectional views of the joint mechanism 60a, showing the closed state and the opened state of the first on-off valve 61 and the second on-off valve 67, respectively.

In the state shown in FIG. 15, the engagement boss 62b of the switching member 62 is positioned at the lower end of the engagement groove 63d of the first opening/closing member 63, and the third O-ring 80c attached to the first opening/closing member 63 is The first on-off valve 61 is closed by being pressed against the inner wall surface of the insertion hole 62a of the switching member 62 .

15 in which the first opening/closing valve 61 is closed, the second opening/closing member 68 is pushed upward by the biasing force of the coil spring 69. As shown in FIG. As a result, the fourth O-ring 80d attached to the second opening/closing member 68 is brought into pressure contact with the periphery of the liquid passage port 65c, and the second opening/closing valve 67 is closed.

When opening the first on-off valve 61, from the state shown in FIG. 15, the lever portion 62e of the switching member 62 is pressed in the circumferential direction with the tip of a screwdriver or the like to move the switching member 62 in a predetermined direction (clockwise direction in FIG. 11). rotate. Here, the rotation of the first opening/closing member 63 is restricted by the engagement between the guide groove 63e and the rotation restricting rib 81. As shown in FIG. As a result, the engaging boss 62b of the switching member 62 moves in the engaging groove 63d of the first opening/closing member 63 from the lower end to the upper end. Since the switching member 62 is fixed to the common flow path 40, the movement of the engagement boss 62b causes the first opening/closing member 63 to move downward. As a result, as shown in FIG. 16, the third O-ring 80c attached to the first opening/closing member 63 is separated from the inner wall surface of the insertion hole 62a of the switching member 62, and the first opening/closing valve 61 is opened. The first opening/closing member 63 smoothly moves downward along the rotation restricting rib 81 by sliding between the guide groove 63 e and the rotation restricting rib 81 . That is, the rotation restricting rib 81 also functions as a guide rib when the first opening/closing member 63 moves vertically.

As the first opening/closing member 63 moves downward, the second opening/closing member 68 that contacts the pressing portion 63b of the first opening/closing member 63 is pressed downward. As a result, the second opening/closing member 68 moves downward in the movement direction against the biasing force of the coil spring 69 . As a result, as shown in FIG. 16, the fourth O-ring 80d attached to the second opening/closing member 68 is separated from the periphery of the liquid passage port 65c of the connecting member 65, and the second opening/closing valve 67 is also opened. Become.

According to the above configuration, the second on-off valve 67 arranged on the side of the connecting member 65 (side of the recording heads 17a to 17c) follows the opening/closing operation of the first on-off valve 61 arranged on the side of the common flow path 40. Open and close. That is, the first on-off valve 61 arranged on the common channel 40 side and the second on-off valve 67 arranged on the connecting member 65 side (recording heads 17a to 17c side) can be opened and closed simultaneously by one operation. can be done. Therefore, when the recording heads 17a to 17c are removed from the head unit 51, the first opening/closing valve 61 or the second opening/closing valve 67 is forgotten to be closed. The risk of forgetting to open the 61 or the second on-off valve 67 is reduced.

Therefore, it is possible to suppress ink leakage or cleaning liquid leakage caused by exchanging the recording heads 17a to 17c without closing the first opening/closing valve 61 or the second opening/closing valve 67. FIG. In addition, it is possible to suppress the occurrence of printing problems caused by forgetting to open the first opening/closing valve 61 or the second opening/closing valve 67 after replacing the recording heads 17a to 17c.

Here, when the first on-off valve 61 and the second on-off valve 67 are closed, the space between the first on-off valve 61 and the second on-off valve 67 (the fluid passage of the connecting member 65 from the insertion hole 62a of the switching member 62) Ink or cleaning liquid remains in the space up to the port 65c. Therefore, even if the recording heads 17a to 17c are removed from the common flow path 40 with the first opening/closing valve 61 and the second opening/closing valve 67 closed, the ink remains between the first opening/closing valve 61 and the second opening/closing valve 67. There is a risk that the ink or cleaning liquid that has been applied may leak out.

Therefore, in the present embodiment, a liquid reservoir 73 having a volume equal to or greater than the space between the first on-off valve 61 and the second on-off valve 67 is provided on the upper surface of the connecting member 65 that constitutes the joint mechanisms 60a to 60c. forming. As a result, when the recording heads 17a to 17c are removed from the common flow path 40, the ink or cleaning liquid remaining between the first on-off valve 61 and the second on-off valve 67 is stored in the liquid reservoir 73. Contamination inside the printer 100 due to leakage of ink or cleaning liquid can be suppressed.

[3. Attachment and detachment procedure of the recording head]
Next, a procedure for attaching and detaching the recording heads 17a to 17c will be described. FIG. 17 is an enlarged view of the vicinity of the joint mechanism 60a on the side surface of the recording head 17b. Here, the procedure for attaching and detaching the recording head 17b will be described, but the procedures for the recording heads 17a and 17c are the same.

When removing the recording head 17b from the common flow path 40, first, by operating the lever portion 62e of the switching member 62, the first on-off valve 61 and the second on-off valve 67 are closed as shown in FIG. . Next, the nine first fixing screws 55 fastened three each to the three joint mechanisms 60a to 60c are removed. By removing the first fixing screw 55 , the connection between the connecting member 65 and the common flow path 40 is released. The recording head 17b is fastened to the common flow path 40 with a second fixing screw 57. As shown in FIG.

Next, the protrusion 71 of the support plate 65b protruding from the opening 53a of the heat sink 53 is pushed down with a finger. As a result, the body portion 65a to which the support plate 65b is fixed is also pushed down together with the support plate 65b against the biasing force of the coil spring 69. As shown in FIG. That is, the connecting member 65 moves from the connecting position to the position (retracted position) retracted downward.

18 is a diagram showing a state in which the connecting member 65 is moved to the retracted position from the state shown in FIG. 17. FIG. 19 is an enlarged perspective view of the gap between the first on-off valve 61 and the connecting member 65 in FIG. 18. FIG. As shown in FIGS. 18 and 19 , a gap D is formed between the first on-off valve 61 and the connecting member 65 as the connecting member 65 moves to the retracted position.

By inserting paper or cloth into the gap D, ink or cleaning liquid remaining between the first on-off valve 61 and the connecting member 65 can be absorbed. Ink and cleaning not completely absorbed by the paper or cloth are stored in the liquid storage section 73 . After that, the second fixing screws 57 fastened to the left and right sides of the recording head 17b are removed, and the recording head 17b is removed from the common flow path 40. FIG.

When the recording head 17b is attached to the common channel 40, the connecting members 65 are connected to the first opening/closing valves 61 of the three joint mechanisms 60a to 60c with the first opening/closing valves 61 closed. Then, the first fixing screw 55 and the second fixing screw 57 are tightened to mount the recording head 17b in the common flow path 40. As shown in FIG. Thereafter, the lever portion 62e of the switching member 62 of each of the joint mechanisms 60a to 60c is operated to open the first on-off valve 61 and the second on-off valve 67, thereby enabling the supply of ink and cleaning liquid to the recording head 17b. .

Further, when the first on-off valve 61 and the second on-off valve 67 are closed, the lever portion 62 e of the switching member 62 overlaps the fastening path of the first fixing screw 55 . Therefore, in order to fasten the first fixing screw 55, it is necessary to operate the lever portion 62e to open the first on-off valve 61 and the second on-off valve 67. As shown in FIG. That is, since the connection member 65 cannot be attached unless the first on-off valve 61 and the second on-off valve 67 are opened, the first on-off valve 61 and the second on-off valve 67 are reliably opened when the connection member 65 is attached. can do.

By attaching and detaching the recording heads 17a to 17c according to the above procedure, leakage of ink and cleaning liquid from the joint mechanisms 60a to 60c can be effectively suppressed with a simple configuration and operation.

In addition, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the present invention. For example, in the above embodiment, the configuration in which the three recording heads 17a to 17c are attached to one head unit 51 has been described. Alternatively, two or four or more recording heads may be mounted.

In the above embodiment, each of the recording heads 17a to 17c has joint mechanisms 60a and 60b for supplying ink and a joint mechanism 60c for supplying cleaning liquid. It can be changed as appropriate according to the configuration and the like.

Further, in the above-described embodiment, an example in which a color printer that records a color image using four colors of ink is used as an inkjet recording apparatus has been described, but a monochrome printer that records a monochrome image using black ink is described. is used, it is possible to use the ink discharge path of the present embodiment.

FIG. 20 is a schematic diagram showing another example of the internal structure of the ink supply path 40a, the cleaning liquid supply path 40b, and the recording heads 117a to 117c that constitute the line head 11Y of the printer 100. As shown in FIG. Note that descriptions of parts common to the configuration of FIG. 5 are omitted.

The recording heads 117a to 117c each have a head front portion 41, a head rear portion 43, a heater 44, and a joint mechanism 160a. The joint mechanism 160 a connects the head front portion 41 and the head back portion 43 . The joint mechanism 160a has an ink supply path 40a and a cleaning liquid supply path 40b through which ink and cleaning liquid flow. The joint mechanism 160a is provided at both longitudinal ends of the recording heads 117a to 117c.

21 is a side sectional view of the joint mechanism 160a in FIG. 20. FIG. FIG. 21 shows the structure of the joint mechanism 160a on the left side of FIG. The joint mechanism 160a on the right side of FIG. 20 has basically the same configuration as that of FIG. 21, but has two first on-off valves 61 for connecting the ink supply path 40a and the cleaning liquid supply path 40b.

As shown in FIG. 21, the joint structure 160a is attached to the end of the ink supply path 40a of the common flow path 40, with one side of the first on-off valve 61 connected to the opening 43a of the head rear surface portion 43. As shown in FIG. Specifically, the switching member 62 of the first on-off valve 61 is provided above the opening 43 a of the head back surface portion 43 . The first opening/closing member 63 of the first opening/closing valve 61 is provided on the opening 43a of the head back surface portion 41 to open and close the ink supply path 40a. The other end of the first on-off valve 61 is connected to a connecting member 65 attached to the opening 41 a of the head front portion 41 . A liquid reservoir 73 is formed at the upper end of the connecting member 65 .

In this manner, in the recording heads 117a to 117b shown in this embodiment, the head front portion 41 and the head rear portion 43 are joined by the joint mechanism 160a. Therefore, when replacing the recording heads 117a and 117b by removing the head front portion 41 and the head back portion 43, it is possible to suppress liquid leakage from the connecting portions.

Moreover, although an example in which the head front portion 41 and the head back portion 43 are joined by the joint mechanism 160a has been shown, the present invention is not limited to this. For example, the head front portion 41 and the head back portion 43 may be joined by a joint mechanism 60a. Even in this case, when the head front portion 41 and the head rear portion 43 are detached to replace the recording heads 117a and 117b, it is possible to suppress liquid leakage from the connecting portions.

INDUSTRIAL APPLICABILITY The present invention can be used for an inkjet recording apparatus such as an inkjet printer having a detachable recording head.

17a to 17c, 117a to 117c recording head 18 ink ejection port (nozzle)
30 cleaning liquid supply section 40 common flow path 40a ink supply path (liquid supply path)
40b cleaning liquid supply path (liquid supply path)
50 Liquid supply mechanism 51 Head unit 60a to 60c, 160a Joint mechanism 61 First on-off valve 62 Switching member 62a Insertion hole 62b Engagement boss 62e Lever part 62f Engagement claw 63 First opening/closing member 63d Engagement groove 63e Guide groove 65 Connection Member 67 Second opening/closing valve 68 Second opening/closing member 69 Coil spring (biasing member)
70 ink supply port (liquid supply port)
71 projection 73 liquid reservoir 81 rotation restricting rib 100 printer (inkjet recording device)

Claims (11)

a common channel having a liquid supply channel through which one or more liquids including ink pass;
one or more recording heads detachable from the common flow path and having a plurality of nozzles for ejecting the ink;
a joint mechanism that connects the liquid supply path and the liquid supply port of the recording head and has a first on-off valve that opens and closes the liquid supply path;
In a head unit that is mounted in an inkjet recording device and performs image recording on a recording medium,
The first on-off valve is
a switching member having an insertion hole and an engagement boss projecting from an inner peripheral surface of the insertion hole;
a sliding portion that is vertically slidably inserted into the insertion hole; and an engaging groove that is formed to be inclined with respect to the axial direction of the sliding portion and engages with the engaging boss. 1 opening and closing member;
a first sealing member attached to the first opening/closing member and in contact with or separated from the inner peripheral surface of the insertion hole;
By rotating the switching member to move the first opening/closing member up and down, the first opening/closing valve is switched between a closed state in which the first sealing member is in contact with the inner peripheral surface of the insertion hole, and the first opening/closing member. 1. A head unit characterized by switching between an open state in which a sealing member is separated from the inner peripheral surface of the insertion hole. The joint mechanism is
a connecting member that connects the first on-off valve and the liquid supply port;
a second on-off valve provided inside the connecting member;
2. The head unit according to claim 1, wherein the second opening/closing valve is opened and closed following the opening/closing operation of the first opening/closing valve. The second on-off valve is
a second opening/closing member that protrudes from the liquid passage port of the connecting member and contacts the first opening/closing member;
a biasing member that biases the second opening/closing member in a direction approaching the first opening/closing member;
a second sealing member attached to the second opening/closing member and in contact with or separated from the periphery of the liquid passage port;
By rotating the switching member to move the first opening/closing member up and down, the second opening/closing valve can be switched between a closed state in which the second sealing member is in contact with the peripheral edge portion of the liquid passage port, and a closed state in which the second sealing member is in contact with the peripheral edge portion of the liquid passage port. 3. The head unit according to claim 2, wherein the head unit is switched between a closed state in which 2 the sealing member is separated from the peripheral portion of the liquid passage port. The switching member has a lever portion operated when rotating the switching member,
The lever portion regulates screw fixation of the connecting member to the common flow path when the first on-off valve is in the closed state, and restricts the screw fixation of the connecting member to the common flow path when the first on-off valve is in the open state. 4. The head unit according to claim 2, wherein the connecting member is allowed to be fixed with screws. The first on-off valve has a guide groove into which a rotation restricting rib projecting from the common flow path is inserted, and rotates the switching member by contact between the rotation restricting rib and an inner wall surface of the guide groove. 5. The head unit according to any one of claims 1 to 4, wherein the rotation of the first on-off valve is restricted when the first on-off valve is closed. The guide groove is formed parallel to the axial direction of the sliding portion, and the first opening/closing member is moved by sliding between the rotation restricting rib and the inner wall surface of the guide groove. 6. The head unit according to claim 5, wherein the head unit moves vertically along the . 7. The head unit according to claim 1, wherein said switching member has an engaging pawl that engages with an engaged portion in said common flow path. a head unit according to any one of claims 1 to 7;
a liquid supply mechanism that supplies the liquid to the head unit;
An inkjet recording device with a head front portion having a plurality of nozzles;
a head rear portion having a liquid supply path through which one or more types of liquid including ink pass, and supplying the liquid to the head front portion;
a joint mechanism that connects the head front portion and the head back portion and has a first on-off valve that opens and closes the liquid supply path;
In a recording head that is mounted in an inkjet recording device and performs image recording on a recording medium,
The first on-off valve is
a switching member having an insertion hole and an engagement boss projecting from an inner peripheral surface of the insertion hole;
a sliding portion that is vertically slidably inserted into the insertion hole; and an engaging groove that is formed to be inclined with respect to the axial direction of the sliding portion and engages with the engaging boss. 1 opening and closing member;
a first sealing member attached to the first opening/closing member and in contact with or separated from the inner peripheral surface of the insertion hole;
has
By rotating the switching member to move the first opening/closing member up and down, the first opening/closing valve can be switched between a closed state in which the first sealing member is in contact with the inner peripheral surface of the insertion hole, and the first opening/closing member. 1. A recording head characterized by switching between an open state in which a sealing member is separated from the inner peripheral surface of the insertion hole. a recording head according to claim 9;
a common channel having the liquid supply channel;
head unit with a head unit according to claim 10;
a liquid supply mechanism that supplies the liquid to the head unit;
An inkjet recording device with

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