JP2002019145A - Ink jet head unit and ink jet recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet head unit in which a nozzle can be recovered from clogging by a simple method and the ink jet head is not discarded but can be used well, and an ink jet recorder comprising that ink jet head unit. SOLUTION: The head unit 25 comprises an ink jet head 24 comprising a joint unit 47, a manifold 71 and an actuator 70, and a base plate 46 for supporting the ink jet head 24. The manifold 71 and the actuator 70 are bonded to one side of the base plate 46 and they are integrated with the base plate 46 so that they can be located at reference positions. A joint unit 47 is fixed removably to the other side of the base plate 46 and filters 82, 94 are provided in the ink channel of the joint unit 47.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet head unit for ejecting ink from nozzles to perform predetermined recording on paper or the like, and an ink jet recording apparatus having the ink jet head unit.

[0002]

2. Description of the Related Art Conventionally, an ink jet recording apparatus has been well known as a recording apparatus having a relatively simple structure and capable of high-speed printing and high-quality printing.

In this type of ink jet recording apparatus, an actuator having a plurality of ejection channels for ejecting ink from a nozzle as droplets is connected to the actuator, and ink is distributed to and supplied to each ejection channel. And an ink jet head having a manifold. In addition, a filter having a smaller diameter than the nozzle diameter is provided at the ink inlet of the manifold in order to remove dust, air bubbles, and the like that cause poor ink ejection when the ink cartridge is mounted. .

[0004] Such an ink jet head is manufactured by welding a filter to an ink inlet portion of a manifold, and then bonding the manifold to an actuator.

[0005]

In such an ink jet head, in the subsequent inspection step, an ejection test is performed to inspect whether or not the nozzles are clogged with foreign matter and ink can be ejected normally. In this injection test, water was flowed from the filter into the manifold and into the actuator, and if there was no clogged foreign matter in the nozzle,
If the water flowing out of the nozzle flows linearly and the nozzle is clogged with foreign matter, the water flowing out of the nozzle bends and flows. Is rejected, and is not allowed to proceed to the subsequent steps.

[0006] However, an ink jet head which failed in this ejection test can be used by removing foreign matter from the nozzles. However, since a filter is welded to the manifold, water is flowed from the nozzle side. It was not possible to perform reverse washing, and a problem of having to discard it as it was occurred.

For this reason, for example, when an ink jet head is screwed to a head holder for positioning a reference position of the ink jet head, and a member provided with a filter is provided in the head holder, when a nozzle is clogged with foreign matter, A method has been proposed in which an ink jet head is detached from a head holder, backwashed by flowing water from a nozzle side, and then attached to the head holder again for use.

However, in such a method, the ink jet head whose reference position has been positioned by the head holder is once removed from the head holder and then mounted again. To match the reference position of
The position must be firmly fixed with screws, causing a trouble that the work is troublesome. In addition, in the case of mounting with such a screw, if the attachment and detachment are repeated a plurality of times, it may not be possible to secure sufficient tightening with the screw, and in such a case, the inkjet head must be discarded. Also occurs.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a simple method for recovering from clogging of a nozzle and to use the nozzle well without discarding it. An object of the present invention is to provide an inkjet head unit capable of performing the above-described operations and an inkjet recording apparatus including the inkjet head unit.

[0010]

SUMMARY OF THE INVENTION In order to achieve the above object, an invention according to claim 1 includes an actuator having a plurality of ejection channels for ejecting ink from a nozzle as droplets, and an actuator having the plurality of ejection channels. In an ink jet head unit including an ink jet head including a flow path forming member for supplying ink to each ejection channel and a base plate supporting the ink jet head, the flow path forming member is detachably connected to the ink supply member. A joint unit connected to the actuator and a manifold for distributing ink to the ink inlet ends of the plurality of ejection channels. The actuator is fixed to the base plate, and is integrated with the base plate in a reference position. Positioning The joint unit is detachably attached to the base plate, an ink flow path for supplying ink from the ink supply member to the manifold is formed, the ink flow path, It is characterized in that a filter is provided.

According to such a configuration, in the injection test, when it is confirmed that foreign matter is clogged in the nozzle, by removing the joint unit provided with the filter from the base plate, water is supplied from the nozzle side. ,
Foreign matter clogged in the nozzle can be removed by flowing out from the manifold side. Moreover, since such cleaning is performed while the manifold and the actuator remain fixed to the base plate for positioning their reference positions, they are always reliably positioned without affecting these reference positions. The state is ensured, and good assemblability can be ensured.

The invention described in claim 2 is the first invention.
In the invention described in (1), a claw portion for engaging with the base plate or the joint unit is formed on one of the joint unit and the base plate, and the claw portion is locked on the other. A locking portion is formed.

According to such a configuration, the claw portion formed on one of the joint unit and the base plate can be easily attached and detached by locking or releasing the locking portion formed on the other. it can. Therefore, the above-mentioned cleaning can be performed more easily. Since the joint unit has nothing to do with the positioning of the reference position, a simple detachable structure by locking or releasing such a claw portion and a locking portion can be provided.

[0014] The invention according to claim 3 provides the invention according to claim 1.
In the invention described in (2), the joint unit is attached to the base plate on a side opposite to the base plate where the manifold and the actuator are fixed, and the joint unit is provided between the joint unit and the manifold. , An ink supply pipe for supplying ink from the joint unit to the manifold is provided via the base plate, and the ink supply pipe is formed of an elastic material.

According to such a configuration, in the above-described cleaning, when the ink supply pipe is detached from the joint unit or the manifold when the joint unit is detached from the base plate, the joint unit can be detached easily. In addition, since the ink supply pipe is formed of an elastic material, the ink supply pipe can be easily attached and detached, and the workability can be improved.

The invention described in claim 4 is the first invention.
The invention according to any one of the first to third aspects, wherein the ink supply member is an ink cartridge, and the joint unit is provided with a guide portion for guiding the mounting of the ink cartridge.

According to such a configuration, the ink cartridge can be mounted on the joint unit along the guide portion, whereby the ink cartridge can be mounted on the joint unit while easily positioning the ink cartridge. Therefore, even if the joint unit is detachably attached to the base plate with a simple configuration, the ink cartridge can be favorably attached to such a joint unit.

According to a fifth aspect of the present invention, there is provided an ink jet recording apparatus comprising the ink jet head unit according to any one of the first to fourth aspects.

With the ink jet head unit according to any one of the first to fourth aspects, good print formation is achieved by the ink jet head in which nozzles are not clogged and the manifold and the actuator are securely positioned. can do.

[0020]

FIG. 1 is a perspective view showing an embodiment of a color ink jet printer as an ink jet recording apparatus of the present invention. In FIG. 1, the color inkjet printer 21 includes an ink cartridge 22 as an ink supply member filled with four color inks of cyan, magenta, yellow, and black, respectively.
And an inkjet head 2 for printing on paper 23
A head unit 25 as an inkjet head unit including the ink cartridge 4, a carriage 26 on which the ink cartridge 22 and the head unit 25 are mounted,
A drive unit 27 that reciprocates the carriage 26 in a linear direction, and a drive unit 27 that extends in the reciprocating direction of the carriage 26,
A platen roller 28 facing the inkjet head 24 and a purge device 29 are provided.

The drive unit 27 includes a carriage shaft 30 disposed at the lower end of the carriage 26 and extending parallel to the platen roller 28, a guide plate 31 disposed at the upper end of the carriage 26 and extending parallel to the carriage shaft 30, Two pulleys 32 and 33 are provided between the shaft 30 and the guide plate 31 and at both ends of the carriage shaft 30, and an endless belt 34 is stretched between the pulleys 32 and 33. .

A carriage shaft support 35 through which the carriage shaft 30 can be inserted is provided at the lower end of the carriage 26, and the guide plate 3 is provided at the upper end of the carriage 26.
1 is provided with a guide plate contact portion 36 that can contact with the guide plate 1.
An endless belt 34 is joined to the rear side surface of the carriage 26.

Then, one pulley 32 is connected to the motor 32
When the pulley 32 is rotated forward and backward by the drive of A, the carriage 26 joined to the endless belt 34 reciprocates linearly along the carriage shaft 30 and the guide plate 31 with the forward and reverse rotation of the pulley 32. Is done.

The paper 23 is an ink jet printer 21
Is fed from a paper feed cassette (not shown) provided on the side of the ink jet head 24 and a platen roller 28.
And predetermined printing is performed by the ink ejected from the inkjet head 24, and then the paper is discharged. In FIG. 1, the illustration of the paper feed mechanism and the paper discharge mechanism of the paper 23 is omitted.

The purge device 29 is provided on the side of the platen roller 28, and is disposed so as to face the ink jet head 24 when the head unit 25 is at the reset position. The purging device 29 is used to prevent ejection failure due to stagnation of ink or growth of bubbles when ink is initially introduced into the inkjet head 24. That is, the purge device 2
9 includes a protective cap 37 that can cover the inkjet head 24, a pump 38 and a cam 39, and an ink storage unit 40. When the head unit 25 is at the reset position, the inkjet head 24 is covered with the protective cap 37. By driving the cam 39, the pump 38 sucks the defective ink including the air bubbles accumulated inside the ink jet head 24 to recover the ink jet head 24. The sucked defective ink is stored in the ink storage unit 40.

FIG. 2 is a perspective view showing a cross section of a main part of the carriage, FIG. 3 is a side view showing the head unit and the ink cartridge in FIG. 2, FIG. 4 is a front view in FIG. 3, and FIG. FIG. 6 is an exploded perspective view of the head unit viewed from above, FIG.
7 is a cross-sectional view of a main part in FIG. 3, FIG. 8 is a cross-sectional view taken along line AA in FIG. 7, FIG. 9 is an enlarged cross-sectional view of a main part in FIG. 7, and FIG. FIG. Next, referring to FIGS. 2 to 10, the head unit 2 will be described.
5 will be described in detail.

In FIG. 2, the carriage 26 has a box shape, and two substantially rectangular openings 41 for mounting the head unit 25 are formed in the lower wall 42. At the front end of each opening 41, locking members 43a, 43b having locking grooves 44 are provided, and leaf springs 45a, 45b are provided on the rear and side walls of the carriage 26 at positions facing the locking members 43a, 43b. It is provided so that it can be attached.

As shown in FIG. 3, a head unit 25 is attached to each opening 41 of the carriage 26. That is, the head unit 25 includes the inkjet head 24 and a base plate 46 to which the inkjet head 24 is attached. For example, as shown in FIG. The projection 48 (see FIGS. 5 and 6) is inserted into the locking groove 44 of the carriage 26, and the rear end and side portions of the base plate 46 are brought into contact with the leaf springs 45a, 45b. By pressing the base plate 46 against the lower wall 42 and the locking members 43a and 43b by 45b, the head unit 25 is mounted so that the reference position of the inkjet head 24 is positioned by the base plate 46.

As shown in FIGS. 7 and 8, the ink-jet head 24 has an actuator 70 having a nozzle 75 for ejecting ink,
A joint unit 47 as a flow path forming member for supplying ink from the ink cartridge 22 and a manifold 71. As shown in FIGS. 5 and 6, an actuator 70 and a manifold 7 are provided.
1 is fixed to one surface of the base plate 46, and the joint unit 47 is detachably attached to the other surface. And as shown in FIG.
Since the actuator 70 and the manifold 71 are assembled to the carriage 26 integrally with the base plate 46 to which they are fixed, the reference position is positioned integrally with the base plate 46. In this state, the actuator 70 and the manifold 71 The joint unit 47 detachably mounts the ink cartridge 22 inside the carriage 26.

As shown in FIG. 2, the two openings 41 of the carriage 26 are formed adjacent to each other, and as shown in FIG.
Each of the openings 41 is attached. Each head unit 25 includes two ink cartridges 2.
2 are mounted in parallel. This allows cyan,
Each of the four ink cartridges 22 of magenta, yellow, and black is divided into two,
5 respectively. Each head unit 25 is provided with one joint unit 47, two manifolds 71, and one actuator 70, as described later, and the ink supplied from each ink cartridge 22 Unit 47
In, after flowing through each independent ink flow path,
The ink is supplied to each of the manifolds 71, supplied to each of the ejection channels 74 formed in two rows in one actuator 70 from each of the manifolds 71, and independently ejected from each of the ejection channel members 74 for each color.

The two side walls of the carriage 26 are shown in FIG.
As shown in FIG. 4, a flexible wiring board 50 connected to a circuit board on the main body side of the printer 21 is provided. COB (chip-on-board) substrate 5 connected to actuator 70 via flexible wiring board 49
1 is detachably connected to a contact provided at the tip of the flexible wiring board 50.

The joint unit 47 has an upper joint 52 and a lower joint 53 made of resin, as shown in FIGS. As shown in FIG. 7, the ink cartridge 2
A guide portion 54 for guiding the mounting of the ink cartridge 2 is formed so as to protrude upward at a front end portion and a rear end portion thereof, and has two ink introduction ports through which ink from each ink cartridge 22 is introduced. 55 is formed upward at the rear side. Further, the upper joint 52 is formed with a claw portion 56 for attaching to the base plate 46, which is formed to protrude downward at a front end portion and a rear end portion. Each ink introduction port 55 has a supply section 6 of the ink cartridge 22.
6 (see FIGS. 3 and 4) are provided with seal members 57 for connection. Further, at the lower end of the upper joint 52, protrusions 86 are formed at four corners facing the manifold 71 in a state where the upper joint 52 is attached to the head unit 25, respectively, toward the base plate 46. On the lower surface, two upper channel grooves 61 are formed along the length direction.

In the lower joint 53, two ink supply cylinders 58 for supplying ink to the ink jet head 24 are formed so as to protrude downward at the front side thereof. Two lower channel grooves 62 are formed along the vertical direction.

As shown in FIGS. 7 and 8, the upper joint 52 is formed with a joint protrusion 59 for joining with the lower joint 53, and the lower joint 53 is joined with the upper joint 52. Groove 60 is formed, and the joining protrusion 59 is ultrasonically welded to the bottom of the joining groove 60, whereby the upper joint 52 and the lower joint 53 are joined in an airtight manner. Two independent ink passages 63 are formed between two upper passage grooves 61 formed on the lower surface of the lower joint 52 and two lower passage grooves 62 formed on the upper surface of the lower joint 53. You. One end of each ink passage 63 is connected to an ink introduction passage 64 in each ink introduction port 55 of the upper joint 52.
And the other end thereof communicates with an ink supply passage 65 in each ink supply cylinder portion 58 of the lower joint 53. The ink introduction passage 64, the ink passage passage 63, and the ink supply passage 65 form a joint unit 47. Has 2
Two independent ink channels are formed.

In each ink passage 63, a filter 82 is provided upstream of the ink supply passage 65. The filter 82 is formed to have a filter diameter smaller than a nozzle diameter of a nozzle 75 to be described later, and is provided to remove dust, air bubbles, and the like that cause ink ejection failure when the ink cartridge 22 is mounted. Have been. It should be noted that a filter 94 is also provided at the inlet end of each ink inlet 55 of the upper joint 52.

Then, the ink cartridge 22 is mounted while being guided along the guide portion 54 of the upper joint 52, and the supply portion 66 of the ink cartridge 22 (FIG.
After the ink supplied from the ink cartridge 22 passes through the filter 94 in the joint unit 47, the ink supplied from the ink introduction port 55 is connected to the ink introduction port 55. The ink is supplied from the ink supply path 64 inside the ink supply path 63, passes through the ink passage path 63, and is supplied from the ink supply path 65 of the ink supply cylinder 58 to the manifold 71 via the filter 82.

The base plate 46 is made of a metal material, that is, a cold-rolled steel plate (SPCC, coefficient of linear expansion 9.5 × 10
⁻⁶ / ° C. to 10.9 × 10 ⁻⁶ / ° C.), and as shown in FIG. 6, an insertion opening 67 for inserting two ink supply pipes 83 described later is provided with a lower opening. At a position facing the two ink supply cylinders 58 of the joint 53, a rectangular opening is formed, and a locking hole 68 as a locking portion for locking the claw 56 of the upper joint 52 is formed with each claw. An opening is formed at a position facing the portion 56. The locking projection 48 is formed at the front end of the base plate 46 as described above, and the concave portions 69 for routing the flexible wiring board 49 are formed at both ends thereof. .

The joint unit 47 is resiliently attached to the base plate 46 by the elasticity of the resin when the claws 56 of the upper joint 52 are locked in the locking holes 68 of the base plate 46. . In this attachment, since each projection 86 of the upper joint 52 is in contact with the base plate 46 as shown in FIG. 9, the base plate 46 applies a pressing force from the joint unit 47 to these projections 86. , And will be distributed and received.

As shown in FIGS. 7 and 8, the actuator 70 is interposed between two channel members 72 having a groove for forming a plurality of injection channels 74 on one surface, and between the two channel members 72. And a center plate 73 as a cover member fixed to one surface of each channel member 72 so as to cover the groove.

Each channel member 72 has a rectangular shape.
Made of a deformable material such as piezoceramic, a plurality of grooves for forming the injection channels 74 are provided.
It is formed in parallel with the ink ejection direction. This groove is
The injection channel 74 is formed between the channel member 72 and the center plate 73 by being fixed to the side surface of the center plate 73, and the injection channel 74 formed thereby sandwiches the center plate 73. It is formed as two rows facing each other. Each ejection channel 74 has, at one end, an ink inlet end 76 into which ink flows, and at the other end, a nozzle 75 for ejecting ink. There is provided an electrode for ejecting the liquid as a droplet.

The center plate 73 has a rectangular plate shape longer than each channel member 72, and is made of a ceramic material, that is, forsterite (linear expansion coefficient 10.5 × 10 4).
⁻⁶ / ° C.). Each channel member 72 is formed on the center plate 73 such that the center plate 73 protrudes toward the base plate 46 more than the ink inlet end 76 of the ejection channel 74. It is fixed.
As shown in FIG. 10, the upper end surface 90 of the center plate 73 protruding from each channel member 72 protrudes to a position lower than the base plate joining surface 89 of the supply portion 78 of the manifold 71 described below. Have been.

As shown in FIG. 8, a flexible wiring board 49 for driving each of the ejection channels 74 is connected to each of the ejection channels 74. That is, the flexible wiring board 49 is formed in two rows so that the terminals of the flexible wiring board 49 are connected to the respective terminals connected to the electrodes provided in the respective ejection channels 74, respectively. Each of the rows of the injection channels 74 is connected to each other.

As shown in FIGS. 7 and 8, the manifolds 71 are arranged above the respective channel members 72 and on both sides of the center plate 73 which is formed so as to protrude, and are supplied from the joint unit 47. And a supply unit 78 for distributing and supplying the ink introduced from the introduction unit 77 to each ejection channel 74 with respect to an ink inlet end 76 of each ejection channel 74.

As shown in FIG. 10, the supply portion 78 has a lower end surface formed as a channel member joining surface 87 joined to an upper end surface of the channel member 72, and a side end surface formed on a side surface of the center plate 73. A center plate joining surface 88 to be joined, and an upper end surface thereof is a base plate joining surface 89 to be joined to the base plate 46. Between the channel member joining surface 87 and the center plate joining surface 88, A groove extending in the length direction is formed, and between the groove and the side surface of the center plate 73,
A supply path 80 for distributing and supplying ink to each ejection channel 74 is formed. And this supply unit 78
Are formed such that the base plate joining surface 89 is higher than the upper end surface 90 of the center plate 73.

In the manifold 71, holding portions 81 for holding the actuator 70 are formed at both ends in the length direction so as to protrude along the side surfaces of the channel member 72.

Then, the manifold 71 and the actuator 70 are held by the holding portion 81 of the manifold 71 by using a jig, and are positioned at predetermined positions by contact. 70 are bonded by a UV adhesive, and then removed from the jig, and as shown in FIG. 10, a joint portion between the upper end surface of the channel member 72 and the channel member joining surface 87 and a side surface of the center plate 73. 7 and the outside of both ends of the supply path 80 in FIG. 7 are sealed with a silicone potting agent 91 using a dispenser.

The actuator 70 and the manifold 71 joined in this way are supported on the base plate 46 as follows. That is,
As shown in FIG. 10, first, the center part in the length direction on the upper end surface 90 of the center plate 73 and the supply unit 7
8, an epoxy-based adhesive 92 is applied using a dispenser to the central portion in the length direction of the base plate joining surface 89, and then, using a jig, a surface of the base plate 46 opposite to the surface on which the joint unit 47 is attached Then, the upper end surface 90 of the center plate 73 and the base plate joining surface 89 of the supply unit 78 are arranged to face each other. In this state, the opposing distance t1 between the base plate joining surface 89 of the supply unit 78 and the base plate 46 is shorter than the opposing distance t2 between the upper end surface 90 of the center plate 73 and the base plate 46. Is done. Then, after temporary bonding with UV adhesive,
After being removed from the jig, the epoxy adhesive 92 is cured by heating. Thereby, between the upper end surface 90 of the center plate 73 and the base plate 46, and the supply portion 78
The base plate joining surface 89 and the base plate 46 are bonded with an epoxy adhesive 92, whereby the actuator 70 is directly bonded to the base plate 46 and the manifold 71 is also directly bonded to the base plate 46.

Further, between the manifold 71 bonded to one surface of the base plate 46 and the joint unit 47 attached to the other surface, two inks for supplying ink from the joint unit 47 to the manifold 71 are provided. The supply pipe 83 is provided via the base plate 46. That is, each ink supply pipe 83
Has a cylindrical shape made of an elastic material such as rubber or elastomer, and is bent in a substantially L-shape as shown in FIG.
One end is connected to each ink supply cylinder 5 of the lower joint 53.
8, and the other end is connected to the introduction portion 77 of each manifold 71 via the insertion opening 67 of the base plate 46.

The ink supplied from the ink supply passages 65 in the respective ink supply cylinders 58 of the joint unit 47 is supplied via the ink supply pipes 83 to the introduction passages 79 in the introduction portions 77 of the respective manifolds 71. Supplied to The ink supplied to the introduction path 79 in the introduction section 77 is
The ink is supplied from the supply path 80 of the supply section 78 communicating with the introduction path 79 to the ink inlet end 76 of each ejection channel 74 while being distributed.

When ink is supplied to the ink inlet end 76 of each ejection channel 74, each ejection channel 7
4 changes the volume of the ink by the ejection pulse signal from the flexible wiring board 49, and
When the volume is reduced, the liquid is ejected from the nozzle 75 as droplets. On the other hand, when the volume is increased, the supply path 8 of the manifold 71 is again supplied.
A predetermined print is formed on the paper 23 by repeating such an operation starting from zero.

As shown in FIGS. 5, 7, and 8, a head cover 84 that covers the actuator 70 and the manifold 71 is attached to the base plate 46. A cover opening 85 for exposing the nozzle 75 of the actuator 70 is formed in the head cover 84. The actuator 70 and the manifold 71 are connected to each other by the head cover 84 in a state where the nozzle 75 is exposed downward. Coated.

Further, as shown in FIG. 8, flexible wiring boards 49 connected to each row of each injection channel 74 are provided.
Of these, the flexible wiring board 49 closer to the COB board 51 is routed from the one concave portion 69 of the base plate 46 toward the COB board 51 as it is, and the flexible wiring board further away from the COB board 51. 49 is temporarily wrapped around the upper surface of the base plate 46 from the other concave portion 69 of the base plate 46,
As shown in FIG. 6, after being sandwiched between the upper surface of the base plate 46 and the lower surface of the lower joint 53, the COB
It is routed toward the substrate 51. These flexible wiring boards 49 are connected to COB boards 51 provided on both side walls of the carriage 26, as shown in FIG.

In the head unit 25 configured as described above, in the inspection process at the time of manufacture, when a foreign matter is clogged in the nozzle 75 in the water ejection test for inspecting normal ink ejection, Filters 82 and 9
If the joint unit 47 provided with the nozzle 4 is removed from the base plate 46 and water is supplied from the nozzle 75 side, foreign matter clogged in the nozzle 75 can be removed from the manifold 7.
1 and can be removed by flowing out from the introduction portion 77 side. Therefore, in the head unit 25, the reverse cleaning can be easily and reliably performed by a simple operation of simply removing the joint unit 47 from the base plate 46. Even so, it is possible to recover the fuel injection again so as to obtain a good injection, and to use it again without discarding. In addition, since such backwashing is performed while the manifold 71 and the actuator 70 are fixed to the base plate 46 for positioning their reference positions, the backwashing is always performed without affecting these reference positions. , And good assemblability to the carriage 26 can be ensured.

Further, in the head unit 25, since the claw portions 56 are formed in the joint unit 47 and the locking holes 68 are formed in the base plate 46, the locking of the claw portions 56 and the locking holes 68 is performed. Alternatively, it can be easily detached by releasing. Therefore, the back washing can be performed more easily.
In the head unit 25, since the joint unit 47 is configured irrespective of the positioning of the reference positions of the manifold 71 and the actuator 70, the engagement or release of the claw 56 and the engagement hole 68 is performed. A simple attachment / detachment structure can be obtained.

When the ink supply pipe 83 is attached to and detached from the joint unit 47 or the manifold 71, the joint unit 47 can be easily attached and detached. In addition, since the ink supply pipe 83 is formed of an elastic material, the ink supply pipe 83 can be easily attached and detached, and the workability is further improved.

Since the guide unit 54 for guiding the mounting of the ink cartridge 22 is formed in the joint unit 47, the upper joint 52 is thus formed.
Even if the joint unit 47 is elastically attached to the base plate 46 by locking the claw portion 56 into the locking hole 68 of the base plate 46, the ink cartridge 22 can be attached to the joint unit 47 along the guide portion 54. By attaching the ink cartridge 22 to the joint unit 47 while easily positioning the ink cartridge 22, the supply unit 66 of the ink cartridge 22 and the ink introduction port 55 can be reliably connected. Therefore, the joint unit 4
The ink cartridge 22 can be satisfactorily mounted on such a joint unit 47 even when the ink cartridge 7 is detachably attached to the base plate 46 with a simple configuration.

Therefore, such a head unit 25
Is provided in the color inkjet printer 21,
Good print formation can be achieved by the inkjet head 24 in which the nozzle 75 is not clogged and the manifold 71 and the actuator 70 are securely positioned.

Further, in such a color ink jet printer 21, since the center plate 73 constituting the actuator 70 is firmly adhered directly to the base plate 46 by the epoxy adhesive 92, the position of the nozzle 75 of the actuator 70 is reduced. Is always directly positioned and held by the base plate 46 regardless of the connection between the actuator 70 and the manifold 71. Therefore, for example, the base plate 4
Actuator 7 is attached to manifold 71 joined to
As in the case where the nozzle 75 of the actuator 70 is joined, a pressing force from another member or a pressing force from the protective cap 37 at the time of purging or non-use is applied to the manifold 71. It is possible to achieve good print formation with less displacement.

Further, the center plate 73 is forstered.
Light (linear expansion coefficient 10.5 × 10 ^-6/ ° C)
The base plate 46 is formed of a cold-rolled steel plate.
(SPCC, coefficient of linear expansion 9.5 × 10^-6/ ° C to 10.9
× 10^-6/ ° C).
Center plate which is a joint part on the side of the actuator 70
A joint portion between the upper end surface 90 of the base plate 73 and the base plate 46 side
The coefficient of linear expansion with the lower surface of the base plate 46 is substantially
Equal, so, for example, by a temperature change,
There is little peeling or cracking between them,
Position of the nozzle 75 caused by peeling or cracking
This has been effectively prevented.

Further, by making these linear expansion coefficients substantially equal to each other, as described above, they can be bonded to each other using the one-component heat-curable epoxy adhesive 92. . Therefore, compared with the case of using the two-component cold-setting epoxy-based adhesive 92, it is possible to adhere with good workability with a longer pot life and a shorter curing time.

Further, the actuator 70 and the manifold 71 are provided only at the central portion in the longitudinal direction on the upper end face 90 of the center plate 73.
6 is bonded, so that, although slightly, a warp or the like may occur due to a temperature change based on a difference in the coefficient of linear expansion, the warp is caused to occur at a portion other than the central portion in the longitudinal direction. Some parts can be acceptable. Therefore, generation of cracks due to such warpage is effectively prevented.

In the head unit 25, the upper end face 90 of the center plate 73 is
And the manifold 71 is disposed on the side of the center plate 73 between the base plate 46 and the channel member 72, so that the manifold 70 can be securely attached to the base plate 46 with a simple configuration. The reliable supply of ink from 71 to the actuator 70 is achieved.

In the head unit 25, the manifold 71 and the actuator 70 are joined to one surface of the base plate 46, and the joint unit 47 is attached to the other surface. The joint unit 47 and the manifold 71 and the actuator 70 are arranged with the base plate 46 interposed therebetween. Therefore, the actuator 70 is
2 and the influence of the pressing force from the joint unit 47, etc.
Only by means of this, the position is securely fixed. Therefore,
The position of the nozzle 75 of the actuator 70 is determined only by the base plate 46, and the occurrence of misalignment is further reduced, and excellent printing is achieved.

Further, an ink supply pipe 8 for supplying ink from the joint unit 47 to the manifold 71 is provided.
Since the ink supply tube 3 is made of rubber, the influence of the pressing force from the ink cartridge 22 and the joint unit 47 and the like can be absorbed by the ink supply pipe 83, so that the manifold 71 and the actuator 70 can be further improved. These ink cartridges 22
In addition, the position of the nozzle 75 is more effectively prevented from being affected by the joint unit 47.

Further, the joint unit 47 is configured such that the claw portion 56 of the upper joint 52 is locked in the locking hole 68 of the base plate 46 so that the base plate 4
6, it is possible to absorb the influence of the pressing force from the ink cartridge 22 and the joint unit 47 at the locking portion between the claw portion 56 and the locking hole 68. Yes, manifold 7
1 and the actuator 70 are further less affected by the ink cartridge 22 and the joint unit 47, and the displacement of the nozzle 75 is more effectively prevented.

Further, such a joint unit 4
7 in the base plate 46,
Since the projection 86 formed on the lower joint 53 is attached so as to abut the base plate 46,
Ink cartridge 22 and joint unit 47
Is applied from the joint unit 47 to the base plate 46 via these projections 86. Therefore, since the base plate 46 can receive the pressing force from the ink cartridge 22 and the joint unit 47 in a dispersed manner, the manifold 71 and the actuator 70 are further affected by the ink cartridge 22 and the joint unit 47. Therefore, the displacement of the nozzle 75 is more effectively prevented.

In the ink jet head 24, when the actuator 70 and the manifold 71 are bonded to the base plate 46, the distance between the upper end surface 90 of the center plate 73 and the base plate 46 is t2. Since the opposing distance t1 between the joining surface 89 and the base plate 46 is shortened and the distance between them is bonded via the epoxy adhesive 92, the center plate having a longer opposing distance is provided. Epoxy-based adhesive 9 between the upper end face 90 of 73 and the base plate 46
2 shrinks more than the epoxy-based adhesive 92 between the base plate joining surface 89 of the manifold 71 having a shorter facing distance and the base plate 46 due to the curing shrinkage.
Rather, it is adhered so as to be attracted to the base plate 46. Then, since the manifold 71 is disposed between the base plate 46 and the channel member 72, the channel member 72 is always elastically urged. (In FIG. 10, the biasing direction is indicated by an arrow 93.) Therefore, this causes the manifold 7 to move.
1 and the actuator 70 are securely fixed, so that, for example, in a process after assembling the ink-jet head 24, even if a thermal history or an external force is applied, it is possible to prevent a displacement between them. it can. As a result, even when the color inkjet printer 21 is used, the manifold 71 and the actuator 70
Can be prevented from being generated due to the positional deviation between the above and the so-called non-discharge after standing can be effectively prevented. In particular, since such a channel member 72 and the manifold 71 are disposed on both sides of the center plate 73, the pressing force from each manifold 71 is applied to each channel member 72 around the center plate 73. Therefore, the manifold 71 and the actuator 70 are more securely fixed, and the displacement between them is more effectively prevented.

The adhesive used for such bonding is not limited to the epoxy-based adhesive 92, but its cure shrinkage is 1 to 10%, and more preferably 3%.
Of these are preferably used. The facing distance t2 between the upper end face 90 of the center plate 73 and the base plate 46 is, for example, 0.75 mm.
The facing distance t1 between the base plate joining surface 89 of the manifold 71 and the base plate 46 is, for example, 0.1 mm.
The preferable ratio (t2 / t1) of these facing distances depends on the curing shrinkage of the adhesive used. For example, when the curing shrinkage is about 3%, Is preferably 2 to 10 times. If this ratio is too large, the residual strain in the adhesive will increase, which may affect the strength of the adhesive itself.

In the above description, the claw portions 56 are formed on the joint unit 47 side and the locking holes 68 are formed on the base plate 46 side.
The locking hole 68 may be formed on the joint unit 47 side, and the claw portion 56 may be formed on the base plate 46 side. In the above description, the projection 86 is formed on the joint unit 47 side.
6 may be formed.

The coefficient of linear expansion between the upper end surface 90 of the center plate 73, which is the bonding portion on the actuator 70 side, and the lower surface of the base plate 46, which is the bonding portion on the base plate 46 side, is substantially the same as described above. Preferably, the substantially equal range is a range having a linear expansion coefficient such that peeling or cracking does not occur therebetween due to a temperature change, regardless of its absolute value. Is about three times the range of the other.

Further, in the color ink jet printer 21, the ink cartridge 22 is mounted on the carriage 26 and mounted on the joint unit 47. However, the ink cartridge 22 is not mounted on the carriage 26, and for example, the ink cartridge 22 is mounted on the carriage 26. The tank may be installed at a fixed position other than the carriage 26, and ink may be supplied from the ink tank to the ink introduction port 55 of the joint unit 47 via a flexible tube.

Further, in the ink jet head 24, the manifold 71 and the channel member 72 are formed as separate components, however, they may be formed as an integrated component.

[0073]

As described above, according to the first aspect of the present invention, the joint unit can be easily and reliably cleaned by a simple operation of simply removing the joint unit from the base plate. The foreign matter clogging the nozzle can be easily and reliably removed without affecting the reference position.
Therefore, even if the injection test is once rejected, the injection can be recovered so that good injection can be obtained again, and can be used again without being discarded.

According to the second aspect of the present invention, the attachment and detachment of the joint unit to and from the base plate can be easily performed by locking or releasing the claw portion and the locking portion. Further, since the joint unit has no relation to the positioning of the reference position, it is possible to provide a simple attaching / detaching structure by locking or releasing the claw portion and the locking portion.

According to the third aspect of the present invention, if the ink supply pipe is detached from the joint unit or the manifold, the joint unit can be easily detached. In addition, since the ink supply pipe is formed of an elastic material, the ink supply pipe can be easily attached and detached, and the workability can be improved.

According to the fourth aspect of the present invention, even if the joint unit is detachably attached to the base plate with a simple configuration, the ink cartridge can be favorably attached to such a joint unit.

According to the fifth aspect of the present invention, good print formation can be achieved by an ink jet head in which nozzles are not clogged and a manifold and an actuator are securely positioned.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of a color inkjet printer as an inkjet recording apparatus of the present invention.

FIG. 2 is a sectional perspective view of a main part of a carriage of the color inkjet printer of FIG.

FIG. 3 is a side view in which a head unit and an ink cartridge are attached in FIG.

FIG. 4 is a front view of FIG.

FIG. 5 is an exploded perspective view of the head unit as viewed from below.

FIG. 6 is an exploded perspective view of the head unit as viewed from above.

FIG. 7 is a side sectional view of a main part in FIG. 3;

FIG. 8 is a sectional view taken along line AA in FIG. 7;

9 is an enlarged sectional view of a main part in FIG. 7;

FIG. 10 is a sectional view of a main part in FIG. 8;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 21 Color inkjet printer 22 Ink cartridge 24 Ink jet head 25 Head unit 46 Base plate 47 Joint unit 54 Guide part 56 Claw part 63 Ink passage way 64 Ink introduction way 65 Ink supply way 68 Lock hole 70 Actuator 71 Manifold 72 Channel member 74 Injection channel 75 nozzle 76 ink inlet end 82 filter 83 ink supply tube 94 filter

Claims (5)

[Claims] 1. An ink jet head comprising: a plurality of ejection channels for ejecting ink from a nozzle as droplets; and a flow path forming member for supplying ink to each ejection channel of the actuator. An ink jet head unit comprising: a base plate supporting an ink jet head; wherein the flow path forming member is connected to the joint unit to which an ink supply member is detachably attached, and an ink inlet end of the plurality of ejection channels is joined to the actuator. A manifold that distributes ink to the base plate, wherein the actuator is fixed to the base plate, and a reference position can be positioned integrally with the base plate. An ink flow path for supplying ink to the manifold from the ink supply member, the ink flow path being provided with a filter, the ink flow path being provided with a filter. Head unit. 2. A claw for engaging with the base plate or the joint unit is formed on one of the joint unit and the base plate, and the claw is locked on the other. The ink-jet head unit according to claim 1, wherein a locking portion is formed. 3. The joint unit is attached to the base plate on a side opposite to the base plate to which the manifold and the actuator are fixed, and between the joint unit and the manifold, 2. The ink supply pipe for supplying ink from the joint unit to the manifold is provided through the base plate, and the ink supply pipe is formed of an elastic material. Or the inkjet head unit according to 2. 4. The ink supply member according to claim 1, wherein the ink supply member is an ink cartridge, and the joint unit is provided with a guide portion for guiding the mounting of the ink cartridge. The inkjet head unit according to any one of the above. 5. An ink jet recording apparatus comprising the ink jet head unit according to claim 1.