JPH03234639A - Ink jet recorder - Google Patents

Abstract

PURPOSE:To prevent poor discharge of a recording head and besides, to enable a number of times of preliminary discharge to be reduced by a method wherein a preliminary discharge means which removes causes for faulty discharge of ink, a preliminary discharge drive means which drives the preliminary discharge means, and a preliminary discharge drive controlling means are established. CONSTITUTION:When a transfer data is received at time t0 from a control part 10, a cap 51 is opened, and a TO timer 804 is started. When 30 sec (beta) is reached at time t1, preliminary discharge is performed. The TO timer 804 is cleared and is started. When the transfer data comes to reach at time t2, a TW timer 803 is started. When 5 sec (gamma) is reached at time t3, the cap 51 is closed, and the TW timer 803 is cleared to be stopped. The TO timer 804 is stopped at 20sec on the way to meaurement, and a TC timer 805 is started. Since preliminary discharge is thus performed when the cap 51 is opened in the case where a period for closing the cap 51 exceeds 60 sec (gamma), the title ink jet recorder can be prevented from falling into a faulty discharge state.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an inkjet recording device.

[Conventional technology]

2. Description of the Related Art Conventionally, recording apparatuses that perform recording on recording media such as paper and OHP sheets (hereinafter also referred to as recording paper or simply paper) have been proposed in the form of mounting recording heads using various recording methods.

This recording head has wire tod type, thermal type,
There are methods such as thermal transfer method and inkjet method.

In particular, the inkjet recording method is attracting attention as a low running cost and quiet recording method because ink is directly jetted onto the recording paper.

In such an inkjet recording device,
Generally, a recording head with an array of fine ejection ports is used. Therefore, when the print head is not operated for a long time, such as when the power is turned off or when print data is not transferred for a predetermined period of time during printing, air bubbles or dust may get inside the ejection ports, or the ink solvent may evaporate. Capping has been performed to prevent the ink from becoming unsuitable for ejection and recording due to increased viscosity or the like. In this method, a cap capable of covering the ejection port forming surface of the print head is disposed, and the ejection port forming surface is covered by the cap when the print head is not in operation.

However, if this capping causes the ejection failure described above, or if an unused or infrequently used ejection port due to the printing pattern becomes the ejection failure, the ink may be refreshed. By doing so, a process (ejection recovery process) is performed to remove these causes of ejection failure.

One form of means for performing such ejection recovery processing is to eject ink from all ejection ports toward the capping cap (hereinafter referred to as There is a method that attempts to remove the causes of ejection failure along with the ink by performing preliminary ejection (called preliminary ejection). Note that an ink absorber is generally provided inside the cap at a portion facing the ejection port in order to prevent ink from leaking or splashing out from the ejection port during preliminary ejection.

Here, performing the above-described preliminary ejection requires time to return the print head to the capping position and time to drive the print head, so it is necessary to reduce the number of preliminary ejections in order to shorten the printing time. Therefore, in conventional inkjet recording apparatuses, preliminary ejection is periodically performed to prevent the print head from falling into a defective ejection state even during printing.

That is, a timer measures the elapsed time after the previous preliminary ejection, and the preliminary ejection is performed every time this elapsed time reaches a predetermined time.

At this time, if the operation is once stopped during the recording operation and the above-mentioned capping occurs, conventionally the timer is cleared and the elapsed time is measured again when the cap is opened and the recording operation is restarted.

Therefore, when the capping time is long or when capping operations occur frequently within the predetermined time period, preliminary ejection is not performed before ejection failure occurs.

Further, in the above case, if preliminary ejection is always performed when the cap is opened, no ejection failure will occur, but there is a problem in that the number of preliminary ejections increases.

[Problem to be solved by the invention]

As mentioned above, in conventional inkjet recording devices, the capping time is not considered (the timing of preliminary ejection is determined), which causes problems such as ejection failure of the print head and an increase in the number of preliminary ejections. It had

Therefore, the present invention has been made to solve the above-mentioned problems, and is designed to prevent the recording head from falling into an ejection failure state.
An object of the present invention is to provide an inkjet recording apparatus that can reduce the number of times preliminary ejection is performed.

[Means to solve the problem]

To this end, the inkjet recording apparatus according to claim (1) of the present invention includes a preliminary ejection drive means that drives the preliminary ejection means to perform preliminary ejection when a predetermined time β has passed after the previously executed preliminary ejection; An inkjet recording apparatus according to claim (2) of the present invention is characterized in that the inkjet recording apparatus comprises a preliminary ejection drive control means for controlling the time during which the ink jet is closed so as not to be included in the predetermined time β. , a first preliminary ejection driving means that drives the preliminary ejection means to perform preliminary ejection when a predetermined time β has elapsed after the previously executed preparatory ejection; A feature characterized by comprising a second preliminary discharge drive means which drives the preliminary discharge means when opening and initializes the predetermined time β of the first preliminary discharge drive means] The above-mentioned claim ( According to the inkjet recording apparatus according to 1), since the time during which the cap is closed is controlled so as not to be included in the predetermined time β, the recording head is not caused to fall into an ejection failure state (preliminary ejection is performed). The number of times can be reduced.

According to the inkjet recording apparatus according to the above aspect (2), when the cap is kept on for a predetermined time period γ, when opening the cap, the preliminary ejection means is driven to perform preliminary ejection, and the Since the predetermined time β is initialized, even if the cap period of the print head is prolonged during the printing operation, it is possible to prevent the print head from falling into a discharge failure state.

〔Example〕

Embodiments of the inkjet recording apparatus of the present invention will be described below with reference to the drawings.

FIGS. 1A and 1B show an example of the external configuration of an embodiment in which the present invention is applied to a document processing device.

Here, reference numeral 1 denotes a keyboard section, on which a group of keys 2 such as keys for inputting characters such as letters and numbers, control keys, etc. are arranged. Now it can be folded as shown.
ing. Reference numeral 4 designates a paper feed tray for feeding a sheet-like recording medium to the printer section 8 inside the apparatus, and it is stored covering the printer section 8 when not in use (as shown in FIG. 5B). Numeral 6 is a feed knob for manually setting and ejecting a recording medium, numeral 6 is a display for displaying inputted text, etc., and 7 is used when transporting the apparatus according to this embodiment.
It is a handle that can be used.

2nd Wi shows an example of the configuration of the printer section 8 according to this embodiment.

Here, reference numeral 9 denotes a head cartridge having an inkjet recording head detailed with reference to FIGS. 3 and 4, and 11
is a carriage on which this is mounted and scans in the S direction in the figure. 13 connects the head cartridge 9 to the carriage 1
1 is a hook for attaching to 1, and 15 is a lever for operating the hook 13. This lever 15 is provided with a marker 17 for indicating a scale provided on a force bar, which will be described later, to make it possible to read the printing position, set position, etc. by the recording head of the head cartridge. Reference numeral 19 denotes a support plate that supports the electrical connection to the head cartridge 9. 21 is a flexible cable for connecting the electrical connection section and the main body control section.

23 is a guide shaft for guiding the carriage 11 in the S direction, and is inserted into a bearing 25 of the carriage 11. A timing belt 27 is fixed to the carriage 11 and transmits power for moving the carriage 11 in the S direction, and is stretched around pulleys 29A and 29B arranged on both sides of the apparatus. Driving force is transmitted to one pulley 29B from the carriage motor 31 via a transmission mechanism such as a gear.

Reference numeral 33 denotes a platen opening 4 for regulating the recording surface of a recording medium such as paper (hereinafter also referred to as recording paper) and for conveying the same during recording, etc., and is driven by a conveyance motor 35. 37 is a paper pan for guiding the recording medium from the paper feed tray 4 side to the recording position, and 39 is disposed in the middle of the recording medium feeding path to press the recording medium toward the platen roller 33 and convey it. It is a feed roller for. Reference numeral 41 denotes a paper discharge roller that is disposed downstream of the recording position in the recording medium conveyance direction and discharges the recording medium toward a paper discharge port (not shown). 42 is a spur provided corresponding to the paper ejection roller 41, and the spur 42
1 to generate a force for conveying the recording medium by the paper ejection roller 41.

43 is a feed roller 39 when setting a recording medium, etc.
, a release lever for releasing the biasing of the presser plate 45 and the spur 42.

Reference numeral 45 denotes a presser plate for suppressing floating of the recording medium in the vicinity of the recording position and ensuring close contact with the platen roller 33. In this embodiment, an inkjet recording head that performs recording by ejecting ink is used as the recording head. Therefore, the distance between the ink ejection orifice forming surface of the printhead and the recording surface of the recording medium is relatively small, and contact between the printing medium and the ejection orifice forming surface must be avoided (the distance must be strictly controlled). Therefore, the arrangement of the holding plate 45 is effective.

47 is a scale provided on the holding plate 45, and 49 is a marker provided on the carriage 11 corresponding to this scale, and the print position and setting position of the recording head can also be read by these.

A cap 51 is made of an elastic material such as rubber and faces the ink ejection orifice forming surface of the recording head in the home position, and is supported so as to be able to come into contact with and separate from the recording head. This cap 51 is used to protect the print head during non-printing operations and during ejection recovery processing of the print head. The ejection recovery process is to eject ink from all ejection ports by driving an energy generating element provided inside the ink ejection ports and used for ink ejection.
This process removes the causes of ejection failure, such as air bubbles, dust, and ink that has thickened and become unsuitable for recording (preliminary ejection).
In addition to this, it is a process for forcibly discharging ink from an ejection port to eliminate causes of ejection failure.

Reference numeral 53 denotes a pump that applies a suction force to forcefully discharge the ink, and is used to suck the ink received in the cap 51 during ejection recovery processing by such forced ejection or ejection recovery processing by preliminary ejection. 55 is a waste ink tank for storing the waste ink sucked by the pump 53, and 57 is a tube that communicates the pump 53 and the waste ink tank 55.

Reference numeral 59 denotes a blade for wiping the ejection orifice forming surface of the recording head, and it has two positions: one in which it protrudes toward the recording head and performs wiping during the head movement process, and the other in a retracted position where it does not engage the ejection orifice formation surface. movably supported. 61 is a recovery system motor; 63 receives power from the recovery system motor 61 to drive the pump 53 and the cap 51;
This is a cam device for moving the plate 59 and the plate 59, respectively.

Next, details of the above-mentioned head cartridge 9 will be explained.

FIG. 3 is an external perspective view of a head cartridge 9 that integrates an ejection unit 9a and an ink tank 9b, which constitute an inkjet recording head main body. In the figure, 906
Denoted at e is a pawl that is hung by a hook 13 provided on the carriage 11 when the head cartridge 9 is mounted.

As is clear from the figure, the pawl 906e is disposed inside the entire extension of the recording head. Further, near the front discharge unit 9a of the head cartridge 9, a positioning abutting portion is provided, although not shown in this figure. Reference numeral 906f denotes a head opening into which a support plate is inserted which stands upright on the carriage 11 and supports a flexible substrate (electrical connection part) and a rubber pad.

FIGS. 4A and 4B are exploded perspective views of the head cartridge shown in FIG. 3, which is of a disposable type with an integrated ink storage section serving as an ink supply source as described above.

In the figure (A), reference numeral 911 is a heater board in which an electrothermal conversion element (discharge heater) and wiring such as Aj for supplying power to the element are formed on a Si substrate using a film forming technique. 921 is a wiring board for the heater board 911, and the corresponding wiring is connected by wire bonding, for example.

Reference numeral 940 denotes a top plate provided with a partition wall for defining an ink flow path, a common liquid chamber, etc., and in this embodiment, it is made of a resin material having an integral orifice spout portion.

For example, 930 is a metal support, and 950 is a pressing spring. By sandwiching the heater board 911 and the top plate 940 between them and engaging them, the urging force of the pressing spring 950 causes the heater board 910 to Top plate 94
0 and fixed by crimping. Note that the support body 930 may also have a wiring board 921 attached thereto by adhesion or the like, and may also have a positioning reference for the carriage 11 that scans the head. Further, the support body 9'30 also functions as a member that radiates and cools the heat of the heater board 911 generated during driving.

960 is a supply tank which receives ink supply from the ink storage section 9b serving as an ink supply source, and which is connected to the heater board 911.
Ink is guided to a common liquid chamber formed by joining the top plate 940 to the top plate 940 (functions as a sub tank. 970 is a filter disposed in a part of the supply tank 960 near the ink supply port to the common liquid chamber, 980 is a lid member of the supply tank 960.

Reference numeral 900 denotes an absorber for impregnating ink, and is disposed within the ink tank body 9b.

Reference numeral 1200 denotes a supply port for supplying ink to the recording element 9a consisting of the above-mentioned parts 911 to 980, and the unit is connected to the part 1010 of the ink tank body 9b.
The absorbent body 900 can be impregnated with ink by injecting ink through the supply port 1200 in a step before disposing the absorbent body 900 in the absorbent body 900 .

1100 is a lid member of the cartridge main body, and 1400 is an atmosphere port provided in the lid member for communicating the inside of the cartridge with the atmosphere. iaoo is a liquid-repellent material disposed inside the atmosphere communication port 1400, and thereby the atmosphere communication port 14
Ink leakage from 00 is prevented.

When the filling of ink into the ink tank 9b via the supply port 1200 is completed, the ejection unit 9a consisting of each part 911 to 980 is positioned and disposed in the part 1010. Positioning or fixing at this time can be performed, for example, by fitting a protrusion 1012 provided on the ink tank body 9b into a corresponding hole 931 provided on the support body 930. The head cartridge 9 shown in (B) is completed.

The ink is supplied from inside the cartridge through the supply port 1200.
, a hole 932 in the support 930 and a supply tank 96
The ink is supplied into the supply tank 960 through an inlet provided on the back side of FIG.
42 into the common liquid chamber. A gasket made of, for example, silicone rubber or butyl rubber is disposed at the above-mentioned common ink connection portion, and this seals the ink supply path to ensure an ink supply path.

The attachment/detachment operation mechanism consisting of the operation lever 15, the hook 13, etc. is located on the side of the carriage 11, that is, on the side of the carriage 1.
Since the attachment/detachment operation mechanism is provided on the moving direction side of the carriage 1, the attachment/detachment operation mechanism does not form a large dead space due to movement of the carriage.

Next, the abutting portion for positioning when installing the head cartridge will be explained.

Reference numeral 601a denotes abutment portions for positioning in the left-right direction, and two abutment portions are provided on the sides of the abutment member 607. Note that for positioning in the left-right direction, an abutment section 601f provided on the support plate 606 is used in addition to the abutment section 601a.

Reference numeral 601b denotes an abutment portion for positioning in the front-rear direction, and is formed at the lower side of the abutment member 607.

Reference numeral 601C denotes abutment portions for vertical positioning, which are formed at two locations: a lower side of the abutment member 607 and a lower side of the support plate.

FIGS. 5A and 5B show the carriage 11, respectively.
FIG. 4 is a top view and a left side view showing the state when the head cartridge 9 is installed.

In these figures, 906a is a contact part provided in the head cartridge 9 so that it can come into contact with the abutment part of the carriage 11 when the recording head is attached, and 906b and 906c are the abutment parts 601b and 601c, respectively. This is a contact part that corresponds to

Here, with reference to No. 51M(A), the engagement relationship of each part when the recording head is mounted will be outlined.

The contact portion 906a of the head cartridge 9 is connected to the carrier 6.
At the same time, the pawl 906 of the head cartridge 9 receives a force to the left in the figure due to the urging force of the coil spring 610 via the hook 13 hooked thereto. As a result, the head cartridge 9 receives a moment force centered on the abutting portion. At this time, the substrate 906d provided on the head comes into contact with the abutting portion 601f, and as a result, the head cartridge 9 is positioned in the left-right direction and the position is maintained.

At this time, the protrusion 605A of the rubber pad 605 is compressed and deformed by contact with the substrate 906d. This deformation causes the terminal pads of the flexible substrate 604 and the substrate 9 to
A force is generated that presses the terminal 06d. In this case, since the substrate 906d is in contact with the abutment portion 601f, the amount of deformation of the protrusion 605A is constant, and the above-mentioned stable pressure contact force can be obtained.

Note that, in this figure, the compressed and deformed state of the protrusion 605A is not shown.

Further, the head cartridge 9 is positioned in the front-rear and up-down directions during the installation process.

6 and 7 are a side view and a top view, respectively, showing the mechanism around the head cartridge shown in FIG. 2 and the like.

In these figures, reference numeral 91 denotes a roller rotatably supported at the front end of the carriage 11. The roller 91 is provided so that a portion thereof protrudes forward from the ejection port surface of the head cartridge, and contacts the paper press plate 45 and rotates thereon. Also, 613 is the carriage 1
This is a roller spring provided at the rear end of 1. Coro spring 61
3 includes a connecting member 613B1 that pivotally supports the rollers 613A and 613A, and a spring 613C that biases the connecting member 613B in a predetermined rotation direction. The roller 613A contacts and rotates on the front end plate 105, which is erected at the front end of the bottom plate 100 of the device so as to extend parallel to the aforementioned guide shaft. The connecting member 613B is rotatably supported by a predetermined support 113 of the carriage 11, and is supported by a spring 6.
13C is supported by a predetermined shaft of the carriage 11 and biases the connecting member 613B to rotate counterclockwise around the shaft 113. Due to the configuration of the roller spring 613 as described above, the carriage 11 is always moved in the direction 5 of the paper pressing plate 45.
energized.

Reference numeral 25 denotes bearings that engage with the guide shaft 23 and are mounted on both ends of the carriage 11. The bearing 25 has a bearing portion eccentric to the case in which it is mounted,
The two bearings 25 are mounted so that their eccentric directions are opposite. Further, the bearing 25 on the side shown in FIG. 6 is provided so as to be swingable about a boss 112 provided on the carriage 11 as an axis. That is, the part of the carriage 11 where the bearing 25 is mounted is an elongated hole, and the movement of the two protrusions 25A of the bearing 25 in the front-rear direction (left-right direction in FIG. 6) is restricted by the boss l12. Ru. As a result, the bearing 25 swings relative to the carriage 11 in response to the movement of the carriage 11. At this time, the movement of the bearing 25 in the direction of the guide shaft 23 is restricted by a protrusion 25B provided on the bearing 25 as a part of the carriage 11.

FIG. 8 is an exploded perspective view of the main parts of the recovery device including the cap 511 pump 53, blade 59, motor 61, cam device 63, etc. in FIG.

Here, 501 is an ink absorber disposed inside the cap 51, 503 is a holding member that holds the cap 51, and 503 is a holding member that holds the cap 51;
A cap lever 05 is rotatably attached around a pin 507, and is used to bring the cap 51 into contact with/disengage from the discharge port forming surface of the discharge unit 9a by the force applied to the pin 507. Reference numeral 511 is a pin that engages with the end portion 509 of the cap lever 505 to restrict the rotation range of the cap lever 505.

A jig 513 has a hole into which the pin 507 of the cap lever 505 is inserted, and is used to attach the cap lever 505 to a support portion 515 provided on the pump 53. Reference numeral 516 is a fastening member for securing the mounting condition. Reference numeral 517 is an acting portion that applies a force to the cap 51 to bring it into contact with the discharge port forming surface, and is engaged with approximately the center of the rear side portion of the cap 51. This action part has an inlet 517A for sucked ink, and has a cap lever 505.
Inside, inside the bottle 507, inside the jig 513, and the support part 5
An ink flow path is formed inside each of the ink cartridges 15 . When the pump 53 applies a suction force, the ink is introduced into the pump 53 through these channels as shown by arrows in the figure.

519 is a shaft protruding from the center of the end face of the pump 53, and the pump 53 itself can rotate around this shaft 519. This rotational force is applied to the cap lever 505 via the support portion 515, and the cap 51 moves forward and backward accordingly. Joint 521 is coupled to member 523 to which tube 57 is attached. These rings 519, joint 5
21 and member 523 are formed with ink flow paths, and the ink sucked by the pump 53 is introduced into the waste ink tank 55 via the tube 57 through these flow paths as shown by arrows in the figure.

525 is the piston of the pump 53, 527 is its shaft, 52
9 is a packing, and 531 is a cap of the pump 53.

533 is attached to the piston shaft 527, and the piston 52
It is a bottle that receives the transmission of force for operating 5.

Reference numeral 535 denotes a blade lever to which the blade 59 is attached, and is rotatably supported around a shaft protruding from the end face of the pump 53, and as the blade lever 535 rotates, the blade 59 is projected or retreated toward the recording head side. 537 is a spring that applies a rotational force to the blade lever 535 in a direction that causes the blade 59 to protrude. Further, 539 is a spring that gives the pump 53 itself the ability to rotate the cap 53 in the direction toward the recording head.

541 is a gear train that transmits the rotation of the motor 61 to the cam device 63. The cam device 63 includes a cam 5 for engaging and rotating an engaging portion 545 provided on the pump 53.
47 and the bottle 5 installed on the piston shaft 527 of the pump 5↓
a cam 549 for engaging with the blade lever 535 to operate the pump; a cam 553 for engaging with and rotating the engaging portion 551 provided on the blade lever 535; and a cam device 63.
f) *-Switch 5 for detecting oscillations
55 and a cam 557 that engages with the cam 55.

The operations of these cams will be described later.

FIG. 9 is a sectional view showing the structure of the cap 51 and the like.

Here, in this embodiment, the ink suction port 56 in the cap is
1 is opened at the bottom in the vertical direction, and an ink flow path 563 is formed toward the ink introduction port 517A provided in the action portion 517 of the cap lever 505. In addition, the suction port 561
is not completely covered by the absorber 501.

According to this configuration, even if ink ejected during ejection recovery processing or the like flows downward due to gravity, the ink is sucked from the suction port 561 provided below, so that the ink absorber 5
The amount of ink remaining in 01 becomes significantly smaller. Therefore, deterioration due to solidification can be significantly delayed, and the life of the ink absorber or the cap 51 to which it is attached can be extended.

FIGS. 10 and 11 are explanatory diagrams showing the contour curves of each cam of the cam device 63 and the operating positions of each part corresponding to each cam position, respectively. Note that the numerical values in FIG. 10 are the rotation angles of the cam.

In these figures, (a) shows the cam position and the state of each part when performing a recording operation, with the cap 51 and blade 59 being separated from the ejection port forming surface of the recording head, and the pump 53 being at the 1-point.

(b) shows the position where the home position switch 55 is turned off, and this position is taken as the home position of the cam device 63.

This is a position set during recording standby, etc. At this time, the cap 51 covers the ejection port forming surface and the blade 5
9 is retracted and the pump 53 is also at top dead center.

When the cam is rotated from position (b), the cap 51
The piston 525 moves toward the bottom dead center while being joined to the discharge port forming surface (cap on), and the negative pressure in the suction system reaching the cap increases. Eventually, the piston 525 reaches the ink inlet of the pump, and after a period of time when it is blocked (a period during which the valve is closed), the valve begins to open (at the 109-5° point), and then fully opens (at the 130,5° point). point), and then the piston 525 reaches a position (c) near the bottom dead center. After sufficient suction is achieved by stopping the rotation of the cam at this position for a predetermined period of time considering the fluid resistance of the ink suction system,
When the cam is rotated again, the piston 525 reaches the bottom dead center and the cap 51 begins to separate from the discharge port forming surface. This position (d) is maintained for a predetermined time.

When the cam is then rotated further, the piston 525 begins to move toward top dead center again. During this process, the valve begins to close (20
9,5° point), then a completely occluded point (230-
On the other hand, at position l (e), the cap 51 is completely separated from the discharge port forming surface.

By driving the piston 525 several times in this vicinity,
The ink remaining in the ink suction system is suctioned (empty suction) to the pump side. Note that the piston 52 inside the pump
The left and right spaces of 5 are communicated by a flow path (not shown), which is closed when the piston moves from the top dead center to the bottom dead center, and is opened when the piston moves from the bottom dead center to the top dead center. Ru. Also,
The space on the right side of the piston communicates with a flow path provided in the pump shaft 519.

Therefore, when the piston 525 moves from the bottom dead center to the top dead center in the process of empty suction, the ink introduced into the space on the left side of the piston is transferred to the space on the right side, and when the piston 525 moves from the top dead center to the bottom dead center, the ink is transferred to the space on the right side of the piston. Ink is introduced into the left-hand space from the suction system, and ink is discharged from the right-hand space into the waste ink tank.

After that, when the cam is further rotated in the forward direction, the blade 59 protrudes and becomes ready for wiping (position 8).
f)). When the carriage 11 is moved toward the recording area in this state, the blade 59 engages with the ejection orifice forming surface of the head and wipes the surface, thereby wiping away ink and the like adhering to the ejection orifice forming surface. Then, the cam is further rotated to move the blade 55 back and set the cam to position (a). In this state, move the carriage 11 to the cap side,
After the discharge port forming surface of the head is opposed to the cap 51,
Move the cam to position (b) to turn the cap on and stop.

Note that when transitioning from standby state to recording, position (b)
Alternatively, the cam may be rotated in the positive or negative direction to cause the blade 59 to protrude, perform wiping, and then perform recording.

Next, a control configuration for controlling each part of the document processing apparatus configured as described above will be explained with reference to FIG. 12.

In the figure, 10 processes characters etc. input from the keyboard section 1 and displays them on the display 6;
This is a control unit that operates the printer unit 8 based on recording instructions from the printer unit 8. This control unit 10 includes an MPUlooO that executes various control procedures, a ROM 1001 that stores the above-mentioned control procedures and data, a RAM 1002 that is used as a work area in executing the above-mentioned control, and character patterns such as characters input from the keyboard unit 1. CG1003 that stores
, and an interface section 1004 that connects to external devices such as the keyboard section 1. The control section 10 and the printer section 8 are electrically connected by a signal line 1005.

The printer section 8 includes a printer control section 80 that controls the head 9 and the like in order to reduce the load on the control section 10 . The printer control unit 80 has almost the same configuration as the control unit 10, and includes an MPU 800, a ROM 801, and a RAM.
802, a timer 803 for measuring time, and an interface unit 804.

Of the printer unit 8, the printer control unit 80 controls the head 9, carriage motor 31, transport motor 35, and recovery motor 61, and the head driver 9A and motor driver 31A135A161A, respectively.
driven by. These motors 31135.61
has a DC motor configuration, and the rotation direction is controlled by the polarity of the drive pulse. Furthermore, based on the detection of the recovery system home sensor 65 and the carriage home sensor 67,
The printer control unit 80 can recognize the cap position and movement position of the carriage 11. Further, it is possible to recognize that a recording medium is set in the paper feed tray 4 based on detection by a transmissive or reflective paper sensor 69 composed of a light emitting element and a light receiving element.

In the above control configuration, when a document creation process is performed and a print start command is issued by pressing the print key (not shown) on the keyboard unit 1, the MPUlooO of the control unit 10 converts the input characters and other documents to CG1003. and convert it to print data.

MPUlooO adds a control command to the converted print data and sends it to the interface unit 1004 and signal line 10.
05 to the printer control unit 80. The MPU 800 of the printer control unit 80 that has received the transfer data interprets the control commands added to the print data based on the command table stored in the ROM 801, and controls the head 9 and the like to execute printing.

FIG. 13 shows a table of the above-mentioned control commands stored in the ROM 801 of the printer control unit 80. In the figure, C1 is a print start command indicating the start of printing, C2
is a print end command indicating the end of printing, and in the case of data spanning multiple pages, it means the end of printing of the last page. C
3 is a data transfer command indicating that the number of print data indicated by the next data to be transferred is to be transferred. Further, C4 is a line feed command indicating the end of one line, C5 is a page start command indicating the start (resume) of -page, and C6 is a page end command indicating the end of -page.

FIG. 14 is a diagram showing a data format transferred from the control section 10 to the printer control section 80. In the case of a document created over multiple pages, first print start command D
I is transferred, data transfer command D2, number of transferred data (N) D3, N pieces of data D4, and line feed command D5
is transferred.

Next, regarding the control procedure in which the printer control unit 80 receives the transfer data from the control unit 10 as described above and performs preliminary ejection and opening and closing of the cap, refer to the flowchart and timing chart shown in FIGS. 15 and 16, respectively. and explain.

The control procedure shown in FIG. 15 is started when the printer section 8 is powered on and a predetermined initialization operation is completed.

1. First, in step S1, the MPU 800 receives data from the control unit 10, and determines whether there is any data to be transferred. If no data has arrived, it is determined in step S2 whether the cap 51 is open. This is an MPU
This can be easily determined since 800 itself controls the opening and closing of the cap 51. If the cap 51 is closed, the process returns to step S1, and if the cap 51 is open, it is determined in step S3 whether a data wait timer (hereinafter referred to as TW timer) 803 has been started. The TW timer is a timer that counts time when no data is sent from the control unit 10, and is used to obtain the timing to close the cap 51. If the TW timer 803 has not been started, it is started in step S4 and the process proceeds to step S5; if it has been started, the process directly proceeds to step S5. In step S5, the TW timer 803 determines whether a predetermined time period α seconds has elapsed.

To explain this predetermined time α seconds, leaving the cap 51 of the recording head open will impede the ejection of ink droplets (therefore, when the transfer data from the control unit 10 is interrupted, the cap 51 Just close it.

However, if the user closes the cap 51 immediately after saying that no data is coming, the time required for recording will be increased by the time required for opening and closing the cap 51. Therefore, the cap 51 is designed to be closed by providing a time α seconds that does not interfere with the ejection of ink droplets, and when the positioning data for α seconds is not received.

Next, if a negative determination is made in step S5, the process returns to step S1. On the other hand, if it is determined that α seconds have elapsed, step S
6, close the cap 51, and close the cap 51 in step S7.
The TW timer 803, which no longer needs to count because the TW timer 803 is closed, is initialized (cleared) and stopped.

The operation of closing the cap 51 described above is performed when the position of the cam device 63 is at the recording operation position (in FIGS. 10 and 11).
This is performed by driving the recovery system motor 61 from a) to the home position (b). Note that the operation of opening the cap 51, which will be described later, is performed by driving the recovery system motor 61 so that the position of the cam device 63 changes from the home position (b) to the recording operation position (a).

Next, in step S8, the cap oven timer (hereinafter referred to as To timer) 804 is temporarily stopped. The TO timer 804 is a timer that counts the time that the cap 51 has been open since the previous preliminary ejection, and is used to obtain the timing of the preliminary ejection. Then, in step S9, a cap close timer (hereinafter referred to as TC timer) 805 is started, and the process returns to step S1. The TC timer 805 is a timer that counts the time that the cap 51 is closed, and is used to determine whether preliminary ejection is to be performed when the cap 51 is opened.

Further, if transfer data is received in step S1, the TW timer 803 is initialized (cleared) in step SIO. Next, in step Sll, it is determined whether the cap 51 is open. If the cap 51 is closed, it is determined in step S12 whether the TC timer 805 has elapsed for a predetermined time period of γ seconds or more. If the judgment is negative, step S
Open the cap at step 18, and open the TC timer 8 at step 519.
Initialize and stop 05. And TO timer 80
4 and proceeds to step S25 (however, if the predetermined time γ seconds or more has elapsed in step S12, the cap 51 is opened in step S13, and the TC is opened in step S14).
The timer 805 is initialized and stopped. Then, in step S15, the TO timer 804 is initialized, and in step S1
Preliminary discharge is performed in step S17, and the TO timer 80 is activated in step S17.
4, and go to step S25 (.

Next, if the cap 51 is open in step Sll,
In step S21, it is determined whether the TO timer 804 has elapsed for a predetermined time period of β seconds or more.

If β seconds have not elapsed, go to step S25 ().

On the other hand, if it has elapsed, the To timer 8
04 is initialized, preliminary ejection is performed in step S23, the To timer 804 is started in step S24, and the process proceeds to step S25. In step S25, step S
In Step 1, the printer performs processing appropriate to the received data (since it is a printer, operations related to printing), and then returns to Step Sl to receive new transfer data.

In the timing chart of FIG. 16 showing the operation according to the above-mentioned control procedure, (a) shows the timing of data transferred from the control unit 10. The reason why data transfer is interrupted is that it may take time for the control unit 10 to convert the data into print data. (b) to (d) are the TW timer 803. TO timer 804. The measurement time of the TC timer 805 is shown. The above-mentioned predetermined times α and β.

γ is set to 5 and 30.6 seconds, respectively. (e) shows the timing of opening and closing of the cap 51, and (f) shows the timing of preliminary discharge.

Upon receiving the transfer data at time t, step S
t, SIO, Sll, S12. Cap 51 at S18
is opened, and the TO timer 804 is started in step 320. Thereafter, steps SI, SI0, 811.
S21. S25 is repeated, but when the TO timer 804 reaches 30 seconds (β) at time 1+, steps 322 to 52
4 to perform preliminary ejection, clear and start the To timer 804.

At time t, when no transfer data arrives, the TW timer 803 is started in steps Sl, S2, S3, and S4. At time t, the TW timer 803 starts for 5 seconds (
γ), step S6 is executed and the cap 51 is
In addition, in steps 57 to 59, TW timer 8 is closed.
03 is cleared and stopped, the TO timer 804 is stopped at 20 seconds during measurement, and the TC timer 805 is started. Therefore, since the TO timer 804 interrupts measurement of the period during which the cap 51 is closed, the predetermined time β does not include the period during which the cap is closed.

When the transfer data arrives at time t4, step 31, S
Proceeds to IO, Sll, S12, at this time TC timer 80
Since 5 is smaller than γ(30), steps 818 to 520
Execute. Therefore, the cap 51 opens, the TC timer 805 clears and stops, and the To timer 804 starts from 20 seconds in the middle of measurement. For this reason, the cap 51
Time 1. 10 seconds after opening. In step S21. S22. S23. S24 is executed and preliminary ejection is performed.

Transfer data does not arrive at time t, and this state is 5.
After continuing for seconds (α), the cap 51 closes at time t7.

Here, it is assumed that there is a long period in which the transfer data does not arrive, and the transfer data arrives at time t8 when the TC timer 805 reaches 80 seconds. In this case, step S1, SI
O.Sll.

The process advances to S12, but since the TC timer 805 is larger than γ(60), steps 313 to 517 are executed. Therefore, the cap 51 is opened and the TC timer 805 is cleared and stopped. Furthermore, after the To timer 804 is also cleared and stopped, preliminary ejection is performed, and the TO timer 804
starts. In this way, if the period during which the cap 51 is closed exceeds 60 seconds (γ), the cap 51
Since preliminary ejection is performed when opening, it is possible to prevent ejection failure from occurring.

Then, at time t, when the TO timer 804 reaches 30 seconds, steps Sl, -S10. Sll.

Since steps 521 to 525 are executed, preliminary ejection is performed.

As explained above, in this embodiment, during the period when the cap 51 is closed, the TO timer 804 is set in step S8.
Since the recording head is stopped in step S20 when the cap 51 is opened, the number of preliminary discharges can be reduced without causing the recording head to fall into a discharge failure state. Therefore, the delay in recording time required for preliminary ejection can be reduced.

In addition, a TC timer 80 determines the time during which the cap 51 is closed.
5 (step S9), and if this time is longer than the predetermined time γ, preliminary ejection is performed in step S16 when opening the cap 51, so even if the cap period of the recording head during recording is prolonged, , it is possible to prevent the recording head from suffering from ejection failure.

In the above-described embodiment, the control unit 10 transfers the recording data to the printer control unit 80 of the printer unit 8, and the printer control unit 80 controls the head 9, etc., to perform recording, but the control unit 10 directly transfers the recording data to the printer control unit 80. It may be configured to control 8.

Furthermore, the present invention brings about excellent effects particularly in bubble jet type recording apparatuses among inkjet recording apparatuses. This is because such a system can achieve higher recording density and higher definition.

As for typical configurations and principles thereof, it is preferable to use the basic principles disclosed in, for example, US Pat. No. 4,723,129 and US Pat. No. 4,740,796. This method is applicable to both so-called on-demand type and continuous type. In particular, in the case of the on-demand type, the electrothermal transducer placed corresponding to the sheet holding the liquid (ink) or the liquid path is required to respond to the recorded information and rapidly exceed nucleate boiling. Application of at least one drive signal that provides a temperature increase causes the electrothermal transducer to generate thermal energy to cause film boiling on the thermally active surface of the recording head. As a result, bubbles in the liquid (ink) can be formed in a one-to-one correspondence with this drive signal, which is effective. The growth and contraction of the bubble causes liquid (ink) to be ejected through the ejection opening to form at least one droplet. If this drive signal is in the form of a pulse, bubble growth and contraction will occur immediately and appropriately.
Particularly responsive liquid (ink) ejection can be achieved,
More preferred. This pulse-shaped drive signal is described in U.S. Pat. Nos. 4,463,359 and 4,345,262.
Those described in the specification are suitable. Note that when the conditions described in the specification of US Pat. No. 4,313,124 concerning the invention regarding the temperature increase rate of the heat acting surface are adopted, the structure of the recording head that can perform even more excellent recording is as follows from each of the above-mentioned specifications. In addition to the combination configuration of the discharge port, liquid path, and electrothermal converter (straight liquid path or right-angled liquid flow path) as disclosed in Disclosing U.S. Patent No. 4558
The present invention also includes the achievements made using the specifications of No. 333 and US Pat. No. 4,459,600. In addition, JP-A-59-123 discloses a configuration in which a slit common to a plurality of electrothermal converters is used as a discharge part of the electrothermal converters.
No. 670, and JP-A-59-138, which discloses a configuration in which an opening for absorbing a pressure liquid of thermal energy corresponds to a discharge part.
The effects of the present invention are also effective even with a recording head configuration based on Japanese Patent No. 461. In other words, regardless of the form of the printhead, printing can be performed reliably and efficiently.

Furthermore, the present invention can be effectively applied to a full-line type recording head having a length corresponding to the maximum width of a recording medium that can be recorded by a recording apparatus. Such a recording head may have a configuration in which the length is satisfied by a combination of a plurality of recording heads, or a configuration as a single recording head formed integrally. In addition, even if it is a serial type like the above example, it is a convertible chip type that can be attached to the device body to enable electrical connection with the device body and supply of ink from the device body. The present invention is also effective when using a recording head or a cartridge type recording head provided integrally with the recording head itself.

In addition, regarding the type and number of recording heads installed, for example, in addition to one type that corresponds to single-color ink, there are also multiple types installed to correspond to multiple inks with different recording colors and densities. It may be something that can be done.

Furthermore, in addition to being used as an image output terminal for information processing equipment such as a computer, the inkjet recording device of the present invention may take the form of a copying device combined with a reader or the like, or even a facsimile device having a sending/receiving function. It may be something.

〔Effect of the invention〕

As explained above, according to the present invention, by performing preliminary ejection in consideration of the time during which the chap is closed, it is possible to reduce the number of preliminary ejections without causing the recording head to fall into a defective ejection state. , it becomes possible to shorten the recording time.

[Brief explanation of drawings]

FIGS. 1A and 1B are perspective views of the external appearance of an embodiment in which the present invention is applied to a document processing device during use and storage, and FIG. 2 shows an example of the configuration of a printer applicable to the present invention. 3 is an external perspective view of the head cartridge shown in FIG. 2; FIGS. 4(A) and 4(B) are an exploded perspective view and an external perspective view of the head cartridge shown in FIG. 5(A) and 5(B) are top and side views showing the state in which the head cartridge is mounted on the carriage, and FIGS. 6 and 7 show the relationship between the carriage and other elements shown in FIG. 2 etc. 8 is an exploded perspective view of the discharge recovery mechanism shown in FIG. 2, FIG. 9 is a side sectional view of the cap portion of the mechanism, and FIG. 10 is a side view and a top view for explaining the engagement relationship. FIG. 11 is a timing chart showing a series of recovery operations in the above mechanism; FIG. 11 is a diagram showing the operation of each part in the ejection recovery operation of the above mechanism over time; FIG. 12 is a control configuration of the recording apparatus shown in FIG. FIG. 13 is a command table showing commands used in the control configuration; FIG. 14 is a data format transferred in the control configuration; FIG. 15 is a flowchart showing a control procedure in the control configuration; FIG. 16 is a timing chart showing the operation in the above configuration. 1-11 Keyboard section 2...Key group row/display 8--Printer section 9...Head cartridge 1, Name of invention section 11--Carriage 31--Carriage motor 3, Detailed description of the invention 51--Cap 53--Pump 61--Recovery motor 63--Cam device 69--Paper sensor 80--Printer control section 501--Absorber 561--Suction port 1, name of the invention So, st A゜ki software゛

Claims (4)

[Claims] (1) A recording head that performs recording by discharging ink onto a recording medium; and a recording head that is formed to be able to open and close with respect to an ejection orifice forming surface that ejects the ink and to cover the ejection orifice forming surface. a cap that opens the cap at the start of driving of the recording head and closes the cap when the non-driving period of the recording head exceeds a predetermined time α; a preliminary ejection means for ejecting ink to eliminate causes of ink ejection failure; a preliminary ejection driving means for driving the preliminary ejection means when a predetermined time β has elapsed after the previous ejection performed by the preliminary ejection means; and the cap driving means. An inkjet recording apparatus comprising: preliminary ejection drive control means for controlling so that the time during which the cap is closed, which is driven by the cap, is not included in the predetermined time β. (2) A recording head that performs recording by discharging ink onto a recording medium; and a recording head that is formed to be able to open and close with respect to an ejection orifice forming surface that ejects the ink and to cover the ejection orifice forming surface. a cap that opens the cap at the start of driving of the recording head and closes the cap when the non-driving period of the recording head exceeds a predetermined time α; a first preliminary ejection drive means that drives the preliminary ejection means when a predetermined time period β has elapsed after the previous ejection performed by the preliminary ejection means; and the cap. When the time during which the cap driven by the driving means is closed exceeds a predetermined time γ, the cap driving means drives the preliminary ejection means when opening the cap, and the first preliminary ejection driving means An inkjet recording apparatus comprising: a second preliminary ejection drive means for initializing a predetermined time period β. (3) The method according to claim (2), further comprising preliminary ejection drive control means for controlling the time during which the cap driven by the cap drive means is closed not to be included in the predetermined time β. inkjet recording device. (4) The recording head is provided with a plurality of ejection ports for ejecting ink and for each corresponding ejection time, and causes a state change in the ink due to heat, and ejects the ink from the ejection ports based on the state change. Claim (1) characterized in that it comprises a thermal energy generating means for forming flying droplets.
The inkjet recording device according to any one of (3) to (3) above.