JPH0366155B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field to Which the Invention Pertains] The present invention relates to an ink jet recording device equipped with a capping means for cleaning the ink ejection orifice surface of the ink jet device and preventing clogging of the ejection orifices.

[Description of conventional technology]

Among the various recording methods currently known, this is a non-impact recording method that generates almost no noise during recording, and is capable of high-speed recording.
Furthermore, the so-called inkjet recording method is recognized as an extremely useful recording method, which has the advantage of being able to record on plain paper without requiring any special fixing treatment.

However, with this inkjet recording method, on the other hand, the ejection orifices of the inkjet recording device used in this method are extremely small (generally, the aperture is on the order of tens of microns), so they can become clogged when recording is not being performed. In such a case, ink may not be ejected normally and there is a fear that recording defects may occur.

For these reasons, in the inkjet recording method, it is almost essential to provide a means to prevent or remove clogging (due to dust adhesion or ink drying) in the ejection port. It is believed that

In the past, many proposals have been made as this type of clogging prevention and removal means, but the devices are complicated and large-scale, require a large amount of cleaning liquid, etc., and the clogging removal effect of cleaning is insufficient. However, none of them has yet reached the level where they can be put to practical use.

Furthermore, it has been difficult to apply the conventional method particularly to inkjet recording apparatuses such as multi-array orifice type inkjet recording apparatuses having hundreds to thousands of ink ejection orifices arranged in parallel.

Therefore, in view of the circumstances of such inkjet recording technology, the present invention provides a capping system for preventing clogging that guarantees good recording quality even in the case of an inkjet recording device in which multiple ejection port arrays are installed. The main purpose is to provide an inkjet recording device equipped with the following.

In other words, the main object of the present invention is to provide an inkjet recording device that guarantees stable ink ejection with a simple system and enables high-speed, high-quality inkjet recording.

An inkjet recording device of the present invention that achieves the above object includes a recording head in which ejection ports for ejecting ink are arranged in a row, and a cap that covers the row of ejection ports, the cap comprising: It has an injection port that injects air to the discharge port array, and an exhaust port from which the air injected to the discharge port array is discharged, and the injection port extends from one end of the discharge port array to the discharge port. In the direction along the row,
It is characterized by being arranged so as to inject air.

Hereinafter, the present invention will be explained in detail based on the drawings.

FIG. 1 is a schematic external perspective view showing an example of an ink jet recording apparatus to which the present invention is applied. In FIG. 1, 101 is a recording head unit, and this recording head unit 101 includes an inkjet head section 103 having a plurality of ejection ports (orifices) arranged in a line as shown at 102 in the figure, and a drive control section 104. and wiring part 1
The head unit 103, drive control unit 104, and wiring unit 105 are connected to each other by bonding wires, flexible printed boards, etc. (not shown), and by inputting recording signals to the wiring unit 105, the head unit 101 can be individually connected. It is set so that printing is possible. 106
is a support plate for the head unit 101, and a plurality of head units 101 are arranged on both the front and back sides of the plate as shown in the figure, so that a predetermined printing paper width (...
In other words, the discharge ports 102 are arranged in a so-called full line (one line). The fixing position of each head unit 101 in the left and right direction is adjusted by a head positioning plate 107 attached to the support plate 106, and the fixing position in the vertical direction is adjusted by a head holding plate 108 with respect to the support plate 106. It is arranged to be detachable.

109 is a matrix flexible printed plate for transmitting output signals from a signal output section (not shown) to the wiring section 105 of each head unit 101 via a cable 110 and a connector 111; , are pressed into contact with individual wiring portions 105 of each head unit 101, and are electrically connected to each wiring portion 105. In this way, the printing plate 109 and each wiring section 105 are not bonded to each other and can be freely attached and detached.

Reference numeral 113 denotes a lead terminal attachment plate, which connects a signal output section (not shown) for driving the head unit 101 to another signal line 114 and each head unit 10.
A signal line (not shown) directly connected to the head portion 103 of the head 1 is securely and freely connected by screwing or the like.

115 and 115' are both ink tanks 116
This is an ink supply pipe for supplying ink from the ink to each head section 103. These ink supply tubes are
Two of them are connected to each head section 103, and when ink is ejected, ink is supplied to the head section 103 through two supply pipes 115, 115'. The mechanism also allows ink to be circulated under pressure between the ink tank 116 and the head section 103, with one side used for pressurized feeding and the other used for ink recovery.

The ink tank 116 is equipped with a cylinder block 117 containing a pressure pump for operating the valve mechanism, and an air filter block 118 having a vent. A removable cap 119 is attached to prevent scattering.

The ink tank 116 is also provided with an ink replenishment port (not shown), through which the ink tank 116 can be filled.
Ink is replenished from a replenishment tank 120 so that the ink level within the replenishment tank 120 remains approximately constant. This replenishment tank 120 is removably locked to the ink tank 116 with fixing claws 121, 121' provided on the ink tank 116 side, making it possible to replace the old and new tanks as necessary. ing. The ink tank 116 is fixed on an ink tank base (not shown), and the ink tank 116 is fixed on an ink tank base (not shown).
It is also fixed to the support plate 106 by 22, 122'.

123 is a cover of the head unit 101 that is provided with grooves for fixing the ink supply pipes 115, 115';
This is to prevent the paper from being contaminated by ink or the like or from being damaged by impact during handling.

124 and 124' are positioning pins,
These are fitted into pin holders attached to a paper conveyance system (not shown) to set a predetermined distance and positional relationship between the ejection opening (orifice) 102 of each head section 103 and the recording paper. There is. Further, the positioning pins 124 and 124' are connected to the support plate 106 by respective brackets 125 and 125'.
is permanently installed.

Reference numeral 126 denotes a board for mounting the illustrated inkjet recording apparatus on an unillustrated device main body with the support plate 106 placed thereon. A mechanism and a capping mechanism for the discharge port 102 are provided.

Further, the support plate 106 has its front part supported by support plate guides 127, 127', and its rear part supported by hinge stands 128, 128' attached to the support plate 106.
Through the hinge holders 129, 129',
It can be slid on two guide shafts 131, 131' via guide shaft collars 130, 130', respectively. The guide shaft 131 is connected to the substrate 1.
26 on the guide bracket 132 (guide shaft 13
1' side is supported by (not shown).

Here, by advancing or changing the guide shaft collars 130, 130' along the respective guide shafts 131, 131', the support plate 106
The head can also be slid on guides 127, 127' and moved in the direction of the arrow in the figure, and the front end surface of the head can be set at a predetermined position such as a recording position, a capping position, a maintenance position, etc., as will be described later.

Reference numeral 133 denotes a cleaner head for capping and cleaning the ejection port 102, and a cleaner (capping) head located opposite the ejection port of the recording head removes dust, solidified ink, etc. that has adhered toward the ejection port. It has an injection port for ejecting air, and an ejection port (suction port) for discharging and removing air after being injected to the ejection port.

The injection port and the discharge port are connected to pressure side tubes 134, 134' for sending air as a cleaning agent and discharge suction side tubes 135, 135' for discharging air, respectively, at locations not shown, and are connected to a joint 136.
and 137, and the joint 136 is connected to the pressure side and the suction side of the pump via a relubricator (not shown), and the discharge side joint 137 is connected to the suction side of the pump via a filter (not shown), respectively. . The cleaner head 133, which also serves as a cap for the entire recording head, is also set so that it can assume a recording position, a capping position, and a maintenance position in response to the movement of the support plate 106.

The support plate 106 also includes hinge bases 128 and 12.
Hinge pins 138 and 13 attached to 8'
The side surface of the discharge port 102 of the support plate 106 can rotate in an arc using the support plate 8' as a pivot, and one end of the support plate 106 is pivoted to a stay angle 140 fixed to the base plate 126. By press-fitting the stay 141 to the stay angle 139 joined to the support plate 106 with screws 142, it can be fixed at a desired angle to the surface of the substrate 126.

Furthermore, attach the fixing screw 142 to the stay angle 139.
By removing the support plate 106 from the substrate 1
It can also be easily removed from 26.

Incidentally, 143 is tube 134, 134', 1
35, 135' on the board 126, and 144 is a tube guide for fixing the cable 11
0, a protective case for the signal line 144. This prevents the cable 110 and the signal line 144 from being damaged or cut due to unexpected application of external pressure when the illustrated inkjet recording device is installed in a device body (not illustrated).

FIG. 2 is a schematic external perspective view for explaining the detailed structure of the cleaner head 133 in the example shown in FIG.

In Fig. 2, the cleaner head 133 is composed of a pressurizing chamber 201, a depressurizing chamber 202, and an outer cover 203, and packings 204, 204' are inserted and secured with screws to prevent leakage between each part. It has been combined. Cleaner head 1
The pressurizing chamber 201, which corresponds to the side facing the ejection opening of the inkjet head 33, has direction plates 205 and 20 at positions corresponding to the head unit (not shown).
5', and serves as a cap for capping the discharge port array of each head unit.
06 is provided. At both ends of each recess 206 are injection ports 20 that inject air toward the discharge port surface.
7 and a discharge port 207 from which the jetted air, etc. is discharged, and the air as a cleaning agent jetted from the jet port flows from one end of the jet port row in a direction along the jet port row. Each discharge port can be efficiently cleaned with the cleaning agent.

The injection port 207 of each recess 206 is connected to the pressurizing chamber 201.
Pressure joints 209 and 209' communicate with each other through a common groove (not shown) in the pressure side tubes 134, 134' shown in FIG.
is familiar with

Similarly, the discharge port 208 connects to the discharge suction joints 210 and 21 through a common groove (not shown) in the decompression chamber 202.
0' to the discharge suction side tube 13 shown in FIG.
5,135' to the joint 137.

Cleaner head 13 configured as described above
Brackets 211 and 211' are attached to both ends of 3, and these brackets are
The shaft 21 is pivotally attached to each support stand 213 and 213'.
2 and 212'. Also,
The brackets are pivotally attached to supports 213 and 213', respectively, and are rotatable about shafts 212 and 212'. Also, brackets 211, 21
Tension is exerted between coil springs 216, 216' which are engaged with hanging pins 214, 214', 215, 215'.

Here, the interlocking operation of the cleaner head 133 and the support plate 106 on which an inkjet head unit (not shown) is placed will be explained using FIGS. 3a, 3b, and 3c.

In FIGS. 3a, b, and c, the hinge stand 128 attached to the support plate 106 is connected to its hinge pin 138.
is locked to the hinge holder 129 by being pivotally supported in the pin receiving groove of the hinge holder 129. Guide shaft collar 13 on hinge holder
0 is inserted, the ring 3 is inserted via the spring 302.
It is locked by 01. At this time, the collar is rotatable within the holder 129. The collar is slidably fitted onto the guide shaft, and this guide shaft 131 is fixed to its bracket 132, and this bracket is further fixed to the substrate 126. There is.

The guide shaft 131 has three ring-shaped grooves 304,
305 and 306 are provided, and these three ring-shaped grooves are connected by an axial groove 307. A guide pin 303 is attached to the guide shaft collar 130.
are attached to the grooves 304, 30.
5, 306, and 307 and can be moved, and the guide shaft collar 130 can be fixed at any ring-shaped position on the guide shaft 131. That is, the collar 130 is moved to a predetermined position by sliding the guide pin 303 in the axial groove 307, and the guide pin 303 is moved into the groove 304, 305, 30.
6, the collar 130 can be fixed to any of the three groove positions of the guide shaft 131.

First, in the embodiment of FIG. 3a, the guide pin 303
is fitted into the ring-shaped groove 304 at the right end in the figure, and the collar 130 is fixed at a position on the guide shaft 131 (furthest from the cleaner head 133).
At this time, the hinge holder 129 is pushed to the left in the drawing via the spring 302, and the hinge stand 128 that is locked to the hinge holder 129 and the support plate 106 connected thereto are pushed against the hinge holder 129.
9 and move to the left in the drawing.

In this state, the tip of the support plate 106 is spaced apart from the cleaner head 133 (which abuts the support stand 213 and stands substantially upright). Therefore, the support plate 106 can be removed from the substrate 126,
The support plate 1 is rotated about the hinge pin 138 as a support shaft.
06 can be fixed at a position away from the cleaner head 133 at an angle with respect to the surface of the substrate 126.
03 and cleaner head 133 is easy to perform maintenance work on.

FIG. 3b shows how the guide pin 303 is connected to the guide shaft 131.
It shows the state when it is fitted into the second ring-shaped groove 305 from the upper right. At this time, Fig. 3a
The support plate 106 moves to the left in the drawing in substantially the same manner as in the case of FIG. Then, the support plate 106 is
Compared to the embodiment shown in FIG.
The head positioning plate 107 located at the tip of the cleaner head 133 comes into contact with the cleaner head 133. In this state, the discharge port rows of each head section 103 shown in FIG. 1 are capped by the cleaner head 133, and the recesses 206 (shown in FIG. ), and can protect the ejection port 102 (shown in FIG. 1) from clogging and adhesion of dust during non-recording. In addition, air is supplied to the injection port 207 (shown in Figure 2).
After the air is injected toward the outlet surface, the air can be discharged from the outlet 208 (shown in FIG. 2) to clean the outlet surface.

FIG. 3C shows a state in which the guide pin 303 is fitted into the third ring-shaped groove 306. The guide pin 303 is passed from the second ring-shaped groove to the third ring-shaped groove 306 through the axial groove 307.
When moving the cleaner head 133 to the position shown in FIG.
9, it is pushed down to the left in the drawing. In this way, the guide pin 303 is inserted into the third ring-shaped groove 306.
When inserted, it is fixed in the state shown in Figure 3 C, and the first
When the positioning pins 124, 124' shown in the figure are fitted into the pin holders (not shown) of the paper transport system, the ejection port 102 is set at a predetermined distance from the paper surface.
The printing operation of the inkjet head section 103 becomes possible. 4a, b, and c are sectional views for explaining in more detail the positional relationship between the head portion 103 and the cleaner head 133 in the state shown in FIG. 3b. Furthermore, Fig. 4a is a partial sectional view of the cleaner head cut in the longitudinal direction, and Fig. 4b is a partial cross-sectional view of the cleaner head cut in the direction of the short side of the cleaner head at the position where the injection port is located. FIG. 4c is a partial sectional view of the cleaner head cut along the short side of the cleaner head at the position where the discharge port is located.

In Figure 4 a, b, c, cleaner head 1
33 is in contact with the positioning plate 107 at the flat portion 401 of the pressurizing chamber 201, and with the ink jet head portion 103 at the convex portion 402 of the pressurizing chamber 201.
Then, the direction plates 205, 205' come into contact with the head positioning plate 107, and the discharge port surface 403 of the head portion 103 is almost sealed and capped within the recess 206 serving as a cap for the discharge port array of the pressurizing chamber 201. It's getting old. Therefore, if the arrangement of the cleaner head 133 and the head section 103 is kept in the state shown in FIG. 3b during non-recording, the ejection ports may become clogged due to volatilization of ink from the ejection ports (not shown) or adhesion of dust. can be prevented.

Furthermore, even if printing defects occur due to clogging of the discharge ports or adhesion of dust, air for cleaning the discharge ports can be discharged from one end of the discharge port array on the discharge port surface 403 from the jet ports 207. By ejecting in the direction along the outlet row and discharging the air etc. injected to the outlet from the outlet 208, clogging and dust can be easily removed.

In this way, in this embodiment, since the ejection port surface on which the ejection ports are arranged is cleaned with air without using liquid, there is no worry that the cleaning liquid will enter the ejection ports, and the ink inside the ejection ports will be cleaned. There is no need to worry about adverse effects such as concentration changes.

In addition, by jetting air from one end of the ejection port array in the direction along the ejection port array, ink, etc. adhering to the upstream side of the ejection port surface moves downstream, and ink, etc. adhering downstream is removed. Since the particles are removed while being collected, the discharge port surface and the discharge port can be cleaned more effectively.

Note that the injection port 207 and the discharge port 208 are connected to the common groove 404 in the pressurizing chamber 201 and the depressurizing chamber 202, respectively.
405, pressure joints 209, 209', and discharge suction joints 210, 210'.

FIG. 5 is a block diagram schematically illustrating one example of a system for pumping and pumping air to and from the cleaner head 133.

In FIG. 5, 501 is a pump, 502, 50
6 is a three-way valve, 503 is a check valve, 504 is an accumulator, 505 and 507 are pressure switches, 5
08 is a lubricator, 509 is a filter, 51
0,511...519 are pipes.

First, the pump 501 pumps the accumulator 50.
Inject air into 4. When the pressure inside the accumulator 504 reaches a predetermined pressure, the pressure switch 505
is activated, the pump 501 is stopped, and the three-way valve 502 is directed in a direction that communicates the pipes 510 and 511.

When the pressure inside the accumulator 504 reaches a predetermined pressure, the three-way valve 506 opens the pipe 514.
When 516 communicates with
The pressurized air in the pipes 514, 516, the lubricator 508, the pipe 517, the joint 136,
It is sent to the cleaner head 133 through the pressure side tube. At this time, the pump 501 is operated by the pressure switch 507 attached to the pipe 516 to generate negative pressure, and air is suctioned from the cleaner head 133 sequentially through the suction side tube, the joint 137, the pipe 518, the filter 509, and the pipe 519. . In other words, the pump 501 is the accumulator 5
It operates when the pressure inside the accumulator 504 is below a predetermined pressure, or when the pressure inside the pipe 516 becomes above a predetermined pressure, and also when the pressure inside the accumulator 504 exceeds a predetermined pressure. Since the pressure inside the accumulator 504 is higher than the predetermined pressure, switch 5 is activated.
When the pump 501 is activated by the pressure switch 505, the pressure air from the pump 501 is discharged from the three-way valve 502 through the pipe 511. The three-way valve 506 is connected to the pipe 515 and 5
If you point it in the direction where 16 leads, the pressurized air will stop,
The pressurized air between the three-way valve 506 and the lubricator 508 is exhausted through the pipe 515, and the pressure switch 507 stops the pump 501.

Also, by adjusting the valve of the lubricator 508,
It is also possible to send only pressurized air.

In the main text of the present invention, detailed explanations of the ink supply system related to the inkjet head section, the drive system of the head, etc. are omitted for convenience.

By using the inkjet recording device according to the present invention as described above, it is possible to simultaneously protect a large number of ink ejection ports from clogging due to ink drying and adhesion of dust, without requiring any complicated ancillary equipment, and to maintain stable performance at all times. It is possible to guarantee accurate inkjet recording.

Since the ejection port surface on which the ejection ports are arranged is cleaned with air without using liquid, there is no fear that liquid or the like will enter the ejection ports, and there is no fear of adverse effects such as changes in the concentration of ink within the ejection ports.

When removing clogging or adhering dust, the air for cleaning is injected from one end of the discharge port row in the direction of the discharge port row, so the discharge port surface can be cleaned efficiently and in a short time. It can be performed.

Since the inkjet device and its capping member can be easily and precisely aligned, capping for preventing clogging can be performed reliably.

It is possible to obtain various effects such as.

[Brief explanation of drawings]

Fig. 1 is an external perspective view of the inkjet recording apparatus of the present invention, Fig. 2 is an external perspective view showing the detailed structure of the cleaner head, and Fig. 3 is an external perspective view of the inkjet recording apparatus of the present invention.
Figures 4a, b, and c are partial cross-sectional views for explaining an embodiment of the present invention.
The figure is a block diagram schematically showing a cleaning system within an inkjet recording apparatus of the present invention. In the figure, 101 is a recording head unit;
2 is an ejection port, 103 is an ink jet head portion,
104 is a drive control section, 105 is a wiring section, 106 is a support plate, 107 is a head positioning plate, 108 is a head holding plate, 109 is a printed board, 110 is a cable, 111 is a connector, 112 is a pressing jig,
113 is a lead terminal mounting plate, 144 is a signal line, 1
15, 115' are ink supply pipes, 116, 120
is an ink tank, 118 is an air filter block, 121, 121' are fixed claws, 122, 12
2' is a fixing metal fitting, 123 is a cover, 124, 12
4' is a positioning pin, 125, 125', 132,
211, 211' are brackets, 126 is a board,
127, 127' are support plate guides, 128, 12
8' is a hinge stand, 129, 129' is a hinge holder, 130, 130' is a guide shaft collar, 131,
131' is a guide shaft, 133 is a cleaner head,
134, 134', 135, 135' are tubes,
136, 137, 209, 209', 210, 2
10' is a joint, 138, 138' are hinge pins, 1
39 and 140 are stay angles, 141 are stays, 142 are screws, 143 are tube guides, 1
44 is a protective case, 201 is a pressurization chamber, 202 is a decompression chamber, 203 is an outer lid, 205, 205' is a direction plate,
206 is a recess, 207 is an injection port, 208 is a discharge port, 212, 212' is a shaft, 213, 213' is a support base, 214, 214', 215, 215' are hanging pins, 216, 216', 302 are springs. , 301
is a ring, 303 is a guide pin, 304, 30
5, 306, 307 are grooves, 308 is a roller stand, 3
09 is a roller, 403 is a discharge port surface, 404, 4
05 is a common groove, 501 is a pump, 502, 50
3,506 is a valve, 504 is an accumulator, 50
5,507 is a pressure switch, 508 is a lubricator, 509 is a filter, 510, 511, 51
2,513,514,515,516,517,
518 and 519 are pipes.

Claims (1)

[Scope of Claims] 1. An inkjet recording device comprising: a recording head in which ejection ports for ejecting ink are arranged in a row; and a cap that covers the ejection port row; and a discharge port from which the air injected into the discharge port row is discharged, and the jet port is arranged in a direction along the discharge port row from one end of the discharge port row. An inkjet recording device characterized by being arranged so as to jet air. 2. The inkjet recording apparatus according to claim 1, wherein the recording head has a plurality of ejection port arrays, and a plurality of caps corresponding to the plurality of ejection port arrays.