JPH06336029A - Ink jet recorder - Google Patents

Abstract

PURPOSE:To obtain an ink jet recorder preventing a counterflow of ink to a capping member of a recovery means. CONSTITUTION:A counterflow preventive space 22 having a larger cross-sectional area in comparison with ink flow paths 14c, 15e is provided in a connecting part between a cap 14 and a cap holder 15. In this manner, a counterflow of ink occurring at the completion of an ink sucking action of a recovery device 11 is checked by the counterflow preventive space 22.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a printer, a copying machine,
The present invention relates to an inkjet recording device that is installed in a facsimile device or the like and that ejects ink onto a recording material according to image information to perform recording.

[0002]

2. Description of the Related Art Conventionally, a recording device such as a printer, a copying machine, a facsimile machine or the like, or a recording device used as an output device such as a composite electronic device including a computer, a word processor or the like, a workstation, etc. An image is recorded on a recording material such as a plastic sheet. Various recording systems such as an inkjet recording system, a wire dot recording system, a thermal recording system, a thermal transfer recording system, and a laser beam recording system are adopted as the recording system of this recording apparatus.

Among these, the ink jet recording method is one in which recording is performed by ejecting ink from a recording means (recording head) onto a recording material, and it is easy to make the recording means compact and a high-definition image is obtained. Can be recorded at high speed,
It is widely used because of its advantages such as low running cost, non-impact system, low noise, and easy color image recording using multicolor inks.

In the above ink jet recording apparatus,
In some cases, foreign matter such as paper dust or dust may adhere to the ink ejection portion of the recording unit (recording head), or the ejection port may be clogged, resulting in ejection failure (including non-ejection). Therefore, in order to prevent this clogging, the ink ejection portion is sealed with a cap at the time of non-recording, and the ink is ejected from the ink ejection port through the cap by a suction means such as a pump so as to normalize the ejection port. A recovery device is provided. For example, in a serial type inkjet printing apparatus, when printing is not performed, the carriage on which the printing head is mounted is stopped at a position facing a cap provided outside the printing range, and the ink is ejected by the cap (ink ejection unit). The outlet forming surface) is configured to be hermetically closed (hereinafter referred to as "capping").

An example of the recovery device will be described with reference to the inkjet recording device shown in FIG. A recording head 51 is mounted on the carriage 52 and reciprocates in the direction perpendicular to the drawing. Reference numeral 53 denotes a cap, which is provided at a predetermined position outside the recording range of the recording head 51, and caps the ink ejection surface of the recording head 51 during non-recording.

The cap 53 is connected to a cylinder 54, and a piston 55 and a piston shaft 56 which are movable in the left-right direction in the drawing are mounted on the cylinder 54. Pump gears 57a, 57 that mesh with each other by a drive source (not shown)
pump cam via gear train formed by b, 57c
When the 58 is rotationally driven, the piston 55 and the piston shaft 56 are moved in the left and right directions by the cam surface provided on the pump cam 58, and the ink is ejected from the ink ejection port of the recording head 51 through the cap 53 in the capping state. The cylinder
The ink is sucked into the cylinder 54, and the sucked ink is discharged from the waste ink pipe 59 connected to the cylinder 54.

FIG. 13 is a schematic view showing a connecting portion of the cap 53 in FIG. 12 with the cylinder 54. In FIG. 13, the cylinder 54 is provided with a cylinder suction pipe portion 54a, and the cylinder suction pipe portion 54a is connected to the cylinder suction pipe portion 54a by fitting and sealing the cap 53. An ink absorber 53a is attached to the upper half of the cap 53 (on the recording head side).
The a is fixed to the cap 53 by an absorber stopper 53b provided on the upper part thereof so as not to fall off. Therefore,
In the cap 53, the ink absorber 53a is a cylinder suction tube portion.
It is attached to the cylinder 54 so as to face the end opening of 54a.

[0008]

However, in the recovery device shown in the above-mentioned prior art, when the piston 55 mounted in the cylinder 54 is returned to a predetermined position after the suction operation, the ink in the cylinder 54 is depleted by the negative pressure. A backflow phenomenon occurs in which the ink remaining in the flow path slightly returns to the cap 53 side. For this reason, for example, the grease used in the cylinder 54 or the waste ink with increased viscosity may be removed by the recording head 51.
There is a risk that the ink may be redeposited on the ink ejection surface side to block the ink ejection port and impair the image quality.

When the ink absorber 53a is provided in the cap 53 in order to reduce the above-mentioned drawbacks or to wet the inside of the cap 53, the ink absorber 53a is not provided.
May come off the cap 53. In addition, the cap 53 is provided with an absorber stopper 53b to form an ink absorber 53a.
If the cap 53 is fixed, the cap 53 has a so-called unreasonable shape of rubber, the yield of the cap 53 is reduced, and the manufacturing cost is increased.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art and to provide an ink jet recording apparatus which prevents backflow of ink to the cap member in the recovery means.

[0011]

A typical means for solving the above-mentioned problems of the prior art and applied to the embodiments described below is a recovery in which a recovery process is performed by sucking ink from the ink ejection portion of the recording means. A means for holding the cap member, a cap member having an ink flow path for covering the ink discharge portion of the recording means, a suction means for sucking ink from the ink discharge portion through the cap member, And a cap holding member in which the ink flow path is formed, and a space having a wide cross-sectional area with respect to the ink flow path is formed at a connecting portion between the cap member and the cap holding member. To do.

[0012]

According to the above means, the space portion having a large cross-sectional area with respect to the ink flow path is formed in the connecting portion between the cap member and the cap holding member, so that the ink generated at the end of the ink suction operation by the suction means. The reverse flow is blocked by the space to prevent the reverse flow.

[0013]

【Example】

[First Embodiment] Next, an ink jet recording apparatus according to an embodiment of the present invention to which the above means is applied will be described. 1 is an explanatory view showing a connecting portion between a cap and a cap holder, FIG. 2 is a perspective explanatory view of a recovery device, FIG. 3 is a sectional explanatory view of the recovery device, and FIG. 4 is a perspective explanatory view of an inkjet recording device.

(Overall Structure) First, a schematic structure of an ink jet recording apparatus will be described with reference to FIG. In FIG. 4, the recording sheet 1 is conveyed by the sheet conveying means 2. At this time, the recording sheet 1 is configured to be pressed by the sheet conveying member 2 a by the sheet pressing member 3 so as not to float from the platen 4.

When the recording sheet 1 is conveyed, a carriage 5 having a recording head 7 as a recording means is reciprocated along a guide rail 6 and at the same time, the recording head 7 is driven to record an image on the recording sheet 1. To do. The recording sheet 1 after recording is guided upward by the guide means 8 and discharged by the discharge means 9. The carriage 5 on which the recording head 7 is mounted is a drive motor (not shown) that is a drive source.
Driving force is transmitted via a transmission means (not shown) such as a pulley and a timing belt to reciprocate.

Further, the sheet conveying means 2 and the discharging means 9
Etc. are driven by a drive motor 10a which is the same drive source, and drive means 10 having this drive motor 10a
Is disposed at one end (left side in FIG. 4) of the inkjet recording apparatus. An ink cartridge 7a for supplying ink to the recording head 7 and a recovery device 11 for removing ink adhesion and the like on the recording head 7 are provided at one end of the ink jet recording apparatus.

Next, the configuration of each of the above parts will be specifically described in order.

(Sheet Conveying Means) The sheet conveying means 2 is
For conveying the recording sheet 1 to the recording position,
ASF (Auto Sheet Feede not shown) as a feeding means
r: recording sheet 1 fed from an automatic paper feeding device) or recording sheet 1 manually inserted from the manual feed port 12
Is to be transported. The sheet conveying means 2 is configured to rotate and drive the conveying roller 2a by the driving force of the driving means 10, and to rotate the pinch roller 2b pressed against the conveying roller 2a, thereby conveying the recording sheet by their cooperative action.

(Sheet pressing member) Sheet pressing member 3
Is to prevent the recording sheet 1 from being lifted from the platen 4 by pressing the recording sheet 1 conveyed by the sheet conveying means 2 against the conveying roller 2a. As shown in FIG. 4, the sheet pressing member 3 is composed of a plate-shaped member that is wider than the moving range of the carriage 5 so as to press the entire recording sheet, and this is conveyed by pressing means such as a spring (not shown). Roller 2a
Is pressed against.

The tip of the sheet pressing member 3 is located below the recording position by the recording head 7, and the recording sheet 1 conveyed to the recording position is pressed by the sheet pressing member 3 against the conveying roller 2a. As a result, the recording sheet 1 does not float above the platen 4 at the recording position. Further, the sheet pressing member 3 is configured such that a tip end portion of a carriage 5 described later is always in contact with the sheet pressing member 3.

(Recording Means) The recording head 7 is for recording an image on the recording sheet 1 conveyed by the sheet conveying means 2, and is mounted on the carriage 5 so as to serially scan the image and perform recording. Has been done.

In a serial type recording apparatus which employs a serial scan system in which main scanning is performed in a direction intersecting the conveying direction (sub-scanning direction) of the recording sheet 1, after setting the recording sheet 1 at a predetermined recording position, a guide rail is provided. An image is recorded (main scanning) by a recording head 7 mounted on a carriage 5 that moves along a line 6, and a recording sheet is conveyed by a predetermined pitch every time one line of recording is completed, and then the recording sheet is stopped again. Recording is performed on the entire recording sheet 1 by repeating the operation of recording (main scanning) the image of the next row in contrast to 1.

As shown in FIG. 4, the carriage 5 is slidably attached to guide rails 6 having both ends fixed to the left and right side walls 13a and 13b and having a circular cross section. Further, the carriage 5 is mounted rotatably around the guide rail 6, and is mounted so that the front side of the carriage 5, that is, the side facing the recording sheet 1 is lowered frontward. Therefore, the leading end of the carriage 5 is moved by the weight of the carriage 5 and the recording head 7 to cause the sheet pressing member 3 to move.
Is configured to abut. As a result, the distance between the recording head 7 mounted on the carriage 5 and the recording sheet 1 is always kept constant.

As the recording means in the above device,
An inkjet recording method is used in which ink is ejected from the recording head 7 to perform recording. That is, this recording head has a fine liquid discharge port (orifice), a liquid passage and an energy acting portion provided in a part of this liquid passage, and energy generation for generating droplet forming energy for acting on the liquid in the acting portion. Equipped with means.

As the energy generating means for generating such energy, a recording method using an electromechanical transducer such as a piezo element, electromagnetic waves such as a laser are radiated to generate heat, and droplets are ejected by the action of the heat generation. There are a recording method using an energy generating means, a recording method using an energy generating means for heating a liquid and discharging the liquid by an electrothermal converter such as a heating element having a heating resistor.

Among them, a recording head used in an ink jet recording method for ejecting a liquid by thermal energy has a high density of liquid ejection ports (orifices) for ejecting recording liquid droplets to form ejection liquid droplets. Since they can be arranged, high resolution recording is possible. Among them, the recording head using the electrothermal converter as the energy generating means can easily be made compact, and has the advantages of the IC technology and the microfabrication technology, which have been remarkably improved in technology and reliability in the recent semiconductor field. This is advantageous because it can be used in two parts, high-density mounting is easy, and the manufacturing cost is low.

(Recovery Means) In the above-mentioned ink jet recording apparatus, ejection failure (non-ejection) due to foreign matter such as paper powder or dust adhering to the ink ejection section of the recording means (recording head) or clogging of the ejection port. (Including) may occur. Therefore, in order to prevent this clogging, the ink ejection portion is sealed with a cap at the time of non-recording, and the ink is ejected from the ink ejection port through the cap by a suction means such as a pump so as to normalize the ejection port. A recovery device is provided. For example, in a serial type inkjet printing apparatus, when printing is not performed, the carriage on which the printing head is mounted is stopped at a position facing a cap provided outside the printing range, and the ink is ejected by the cap (ink ejection unit). The outlet forming surface) is configured to be hermetically closed (hereinafter referred to as "capping").

As shown in FIG. 4, a recovery device 11 is provided at the left end of the moving range of the carriage 5. The recovery device 11 has a function of covering the ink ejection surface of the recording head 7 at the time of non-recording to prevent the ink near the ink ejection port of the recording head 7 from being dried and solidified due to the drying. Hereinafter, a specific configuration will be described with reference to FIGS. 2 and 3.

In FIG. 2, reference numeral 11a is a flexible wiper, which is fixed to the pump base 11b and is configured to always contact the recording head 7 with a constant overlap amount. Therefore, the recording head 7 is the recovery device.
It is configured to wipe off the front surface of the recording head whenever it moves toward 11.

Reference numeral 11c is a rubbing member made of a porous material such as ether-based polyurethane continuous pores, and is provided on the right side of the rubbing lever 11d. Also rubbing lever 11
d is supported by a pump base 11b, and is rotatable by the movement of the recording head 7. The rear portion of the rubbing lever 11d is guided by a cam (not shown) provided on the right side surface of the pump cam 11e, receives rotation when riding on the cam, and reaches a position where the rubbing member 11c overlaps the recording head 7. It is configured to move forward. Then, with the rubbing member 11c moved forward, the carriage 5 moves from left to right to a position facing the rubbing member 11c, whereby ink and impurities on the ink ejection surface of the recording head 7 are removed, and the recording head Ink ejection stability of No. 7 is secured.

Further, the pump cams 11e and 11f are integrated with a positioning dowel (not shown), and the pump cam shaft 11g.
Is rotatably attached to. Elliptical groove portions are bored on opposite surfaces of the pump cams 11e and 11f so that both ends of the parallel pin 11i integrally connected to the piston 11h can slide, and the elliptical groove portions are formed depending on the rotation of the pump cams 11e and 11f. The parallel pin 11i is moved up and down to generate a negative pressure.

Next, the structure of the capping unit will be described with reference to FIG. The cap 14 is the recording head 7
It is configured by using an elastic member such as rubber that elastically presses against the outer edge portion of the ink ejection surface, and has a vent hole 14a and an ink suction space 14b. Also above the cap 14
Are held by a cap holder 15, and the cap holder 15 is held by a holder 16.

On the back surface of the cap holder 15, a projection 15a having a rod-like shape and a tip portion penetrating the rear wall of the holder 16 is provided in a protruding manner, and a coil spring 15b is fitted on the projection 15a. An E-ring 15c for restricting the movement of the cap holder 15 toward the recording head is attached to the tip of the protrusion 15a. The cap holder 15 is held by the holder 16 so as to be movable in the left-right direction in the drawing along a guide (not shown) provided in the holder 16, and the holder 16 is provided with respect to the pump carriage 17 with respect to the pump carriage 17. It is held so as to be movable in the left-right direction in the drawing along a guide (not shown) provided in the.

A groove 16a is formed in the rear portion of the holder 16, and a rail 18 is inserted in the groove 16a.
The rail 18 is divided into two parts in the vertical direction, the lower rail 18b is used for advancing or retreating with respect to the recording head 7, and the upper rail 18a is for the atmosphere opening valve 19.
It is used to open and close. A rail arm portion 18c is provided at the back of the rail 18, and a rail dowel portion 18d is provided at the tip thereof.

An atmosphere opening valve 19 is provided on the back surface of the holder 16 and is urged to the left side in the figure by a spring 16b. Therefore, the atmosphere release valve 19 is connected to the upper rail 18
It is attached so as to be movable in the left-right direction in the figure along a.

The atmosphere release valve 19 is attached to the holder.
16 Insert from above and fix. Also, the atmosphere release valve 19
Is arranged in front of the vent 14a provided in the cap 14, and the ink suction space 14b can be closed by closing the vent 14a with the atmosphere opening valve 19.

Further, an ink absorber is provided on the bottom of the cap 14.
20 is provided, which absorbs and holds the ink when sucking the ink and prevents the nozzle from drying during capping. A suction tube 21 is connected to the bottom of the cap 14, and the suction tube 21 is connected to a cylinder 11j having a piston 11h shown in FIG. 2 to perform an ink suction operation.

Next, the cap 14 and the cap holder 15
The configuration of the connecting portion will be described with reference to FIG. Figure 1
The cap 14 is the fitting portion 15 of the cap holder 15.
It is fitted and connected to d and is configured to be sealed by the outer peripheral surface of the fitting portion 15d and the inner peripheral surface of the cap 14. The cap 14 has an ink suction space 14b that faces the ink ejection surface of the recording head 7 and sucks ink.
And an ink flow path 14c continuous therewith is formed,
An ink flow path 15e is formed in the cap holder 15. A backflow stop space 22 is formed at the connecting portion between the cap 14 and the cap holder 15, and the backflow stop space 22 is provided in the front and rear ink flow paths 14d and ink flow paths.
They are in communication with 15e respectively. The backflow prevention space 22 is formed with a larger cross-sectional area than the ink flow paths 14d and 15e, and is formed in a state where the cap 14 is connected to the cap holder 15.

The cap holder 15 and the suction tube 21
And are sealed by a joint 23. By operating the pump cams 11e and 11f shown in FIG. 2, the piston 11h is moved up and down to eject the ink of the ink absorber 20 in the cap 14 via the suction tube 21 or the ink ejection of the recording head 7 in the capping state. Ink is sucked into the cylinder 11j from the outlet.

According to the above construction, even if a backflow generated by the negative pressure when the piston shaft in the cylinder (not shown) is returned is generated in the suction tube 21, the backflow stopping space 22 dams the backflow ink. The ink is prevented from flowing back into the ink suction space 14b directly opposed to the recording head 7 in 14 to prevent the thickened ink from reattaching to the recording head 7. As a result, high image quality can be maintained, and the safety and reliability of the device can be improved.

(Guiding Means) The guiding means 8 guides the recording sheet 1 recorded by the recording head 7 to the discharging means 9 and prevents the recording sheet 1 from rising from the platen 4. As shown in FIG. 4, the guide means 8 is provided with a spur 8 disposed upstream in the recording sheet conveying direction.
a and a spur 8b disposed on the downstream side, and the spurs 8a and 8b serve as guide rotating bodies, respectively.

(Ejecting Means) The ejecting means 9 is for ejecting the recording sheet 1 recorded by the recording head 7, and comprises an ejecting roller 9a and a spur 8b contacting the ejecting roller 9a. The roller shaft 9b of the discharge roller 9a
A discharge gear 9c is attached to one end of the discharge gear 9c, and the discharge gear 9c is rotated by the driving force transmitted to the discharge roller 9a via the gear train of the driving means 10 having the drive motor 10a. When the discharge roller 9a rotates, the recording sheet 1 is conveyed and discharged to the outside of the apparatus by the cooperative action with the spur 8b.

[Other Embodiments] Next, another example of the recovery device equipped in the above-mentioned ink jet recording apparatus will be described with reference to the drawings. The schematic configuration of the ink jet recording apparatus is substantially the same as that of the above-described embodiment, and the same members are designated by the same reference numerals and the description is cited.

Second Embodiment In FIG. 5, this embodiment is one in which the ink absorber 20 is mounted in the backflow stop space 22 formed in the connecting portion between the cap 14 and the cap holder 15. As a result, it is possible to prevent the backflow of ink and to keep the ink suction space 14b in a wet state while the recording head 7 is capped, and to prevent the ink ejection port of the recording head 7 from drying. When the recording head 7 preliminarily ejects the ink into the cap 14 before recording, it is possible to absorb and hold the ink by the ink absorber 20.

[Third Embodiment] Next, referring to FIG. 6, in the present embodiment, a cylinder 24 is used as a cap holding member, and a cap 14 is fitted and connected to a fitting portion 24a formed on a side wall of the cylinder 24. It is a thing. The sealing connection between the cap 14 and the cylinder 24 is performed by the inner peripheral surface of the cap 14 and the outer peripheral surface of the cylinder 24.

In addition, the cap 14 has an ink suction space facing the ink ejection surface of the recording head 7 for sucking ink.
14b and an ink flow path 14c continuous therewith are formed, and an ink suction pipe portion 24b is formed in the fitting portion 24a of the cylinder 24. The ink suction pipe portion 24b communicates with the backflow stop space 22. A backflow stop space 22 is formed at the connecting portion between the cap 14 and the cylinder 24,
The backflow stop space 22 is provided in the front and rear ink flow paths 14c.
And the ink suction tube portion 24b. The backflow stop space 22 includes the ink flow path 14c and the ink suction tube portion 24b.
Formed with a larger cross-sectional area than the cap
14 is formed to be connected to the cylinder 24. An ink absorber 20 is mounted in the backflow stop space 22. According to the above configuration, it is possible to prevent the ink from flowing back to the recording head 7 and to further simplify the configuration of the recovery device 11.

[Fourth Embodiment] Next, referring to FIG. 7, in this embodiment, the inner peripheral surface of the cap 14 and the outer peripheral surface of the ink suction tube 24b of the cylinder 24 are hermetically connected. Further, in this embodiment, the ink suction pipe portion 24b of the cylinder 24 has a wide inner diameter, and the ink suction pipe portion 24b is expanded.
The backflow stop space 22 is also used by b, and the ink absorber 20 is attached to the expanded ink suction tube 24b. According to the above configuration, the ink flow path can be shortened and the space for mounting the ink absorber 20 can be efficiently used.

The structure of the cylinder 24 will be described. Inside the cylinder 24, a piston 25 and a piston shaft 26 which are movable in the left-right direction in the drawing are mounted. When a pump cam (not shown) is rotationally driven by a drive source (not shown), the piston 25 and the piston shaft 26 are moved left and right by a cam surface formed on the pump cam,
Ink is sucked into the cylinder 24 through the cap 14 from the ink discharge port of the recording head 7 through the cap 14 in the capping state, and is absorbed and held by the ink absorber 20.

[Fifth Embodiment] Next, referring to FIG. 8, this embodiment shows a structure in which the cap 14 and the cylinder 24 are connected in a hermetically sealed manner by the outer peripheral surface of the cap 14 and the inner peripheral surface of the cylinder 24. Is. The ink absorber 20 is
Like the third embodiment, it is mounted in the backflow stop space 22 formed at the connecting portion between the cap 14 and the cylinder 24.

[Sixth Embodiment] Next, referring to FIG. 9, this embodiment shows a case where the cap 14 and the cylinder 24 are connected not by the fitting structure but by the sandwiching structure.
A flange portion 14d is formed on the lower surface of the cap 14 and is brought into close contact with the side wall of the cylinder 24. Then, the upper surface of the flange portion 14d is fixed to the side wall surface of the cylinder 24 using a cap stopper 27, and the cap 14 is connected by being sandwiched. As a result, the shape of the cylinder 24 can be simplified and the connecting structure between the cap 14 and the cylinder 24 can be made more reliable. The ink absorber 20 is a cap similar to the second, third and fifth embodiments.
Backflow stop space formed at the connection between 14 and cylinder 24
It is attached to 22.

[Seventh Embodiment] Next, referring to FIG. 9, in the present embodiment, in order to further simplify the shape of the cap 14 shown in the sixth embodiment, a backflow preventing space 22 is formed in the side wall of the cylinder 24. The ink absorber 20 is mounted in this space 22. The structure for connecting the cap 14 to the cylinder 24 is performed by sandwiching the flange portion 14d with the cap stopper 27 as in the sixth embodiment.

[Eighth Embodiment] Next, referring to FIG. 10, this embodiment is a modification of the fixing structure of the cap 14 of the seventh embodiment. That is, two hook portions 24c are provided on the side wall of the cylinder 24 at intervals corresponding to the diameter of the flange portion 14d of the cap 14.
It is formed at a location, and the flange portion 14d is connected and fixed by a hook portion 24c. This allows the cap 14
It is possible to more reliably connect and hold the cylinder to the cylinder.

[Ninth Embodiment] Further, in each of the above-described embodiments, the ink jet recording system is used as the recording means, but the electrothermal converter is energized according to a recording signal and the heat applied by the electrothermal converter is applied. It is more preferable that the recording is performed by ejecting the ink from the ejection port due to the growth and contraction of the bubbles generated in the ink by utilizing the film boiling generated in the ink by the energy.

With regard to its typical structure and principle, it is preferable to use the basic principle disclosed in, for example, US Pat. Nos. 4,723,129 and 4740796. This method can be applied to both the so-called on-demand type and continuous type, but in the case of the on-demand type in particular, it is arranged corresponding to the sheet or liquid path holding the liquid (ink). By applying at least one drive signal to the electrothermal transducer, which corresponds to the recorded information and gives a rapid temperature rise beyond nucleate boiling,
This is effective because heat energy is generated in the electrothermal converter to cause film boiling on the heat acting surface of the recording head, and as a result, bubbles in the liquid can be formed in a one-to-one correspondence with this drive signal. Due to the growth and contraction of the bubbles, the liquid is ejected through the ejection openings to form at least one droplet. It is more preferable to make this drive signal into a pulse shape because bubbles can be grown and contracted immediately and appropriately, so that particularly excellent liquid ejection can be achieved.

As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. If the conditions described in US Pat. No. 4,313,124 of the invention relating to the rate of temperature rise on the heat acting surface are adopted, more excellent recording can be performed.

As the constitution of the recording head, in addition to the combination constitution of the ejection port, the liquid passage, and the electrothermal converter (the linear liquid passage or the right-angled liquid passage) as disclosed in the above-mentioned respective specifications. The present invention also includes configurations using US Pat. Nos. 4,558,333 and 4,459,600, which disclose configurations in which the heat acting portion is arranged in a bending region.

Further, Japanese Unexamined Patent Publication No. 59-123670 discloses a structure in which a common slit is used as a discharge portion of a plurality of electrothermal converters, and an opening for absorbing a pressure wave of thermal energy. Japanese Patent Laid-Open Publication No.
The effect of the present invention is effective even if the configuration is based on Japanese Patent Laid-Open No. 59-138461. That is, according to the present invention, recording can be surely and efficiently performed regardless of the form of the recording head.

As the serial type recording head described above, the recording head fixed to the carriage or mounted on the carriage enables electrical connection with the apparatus main body and supply of ink from the apparatus main body. A replaceable chip type recording head, or a cartridge type recording head in which an ink tank is integrally provided in the recording head itself may be used.

Further, it is preferable to add a recovery means for the recording head, a preliminary auxiliary means, etc., which are provided as a constitution of the ink jet recording apparatus of the present invention, because the effects of the present invention can be further stabilized. Specifically, these are capping means, cleaning means, pressurizing or suctioning means for the recording head, preheating means by electrothermal conversion type or other heating element or a combination thereof, and recording. It is also effective to perform a stable recording by performing a preliminary discharge mode in which another discharge is performed.

Regarding the type and number of recording heads mounted on the carriage, for example, only one is provided corresponding to a single color ink, or a plurality of inks having different recording colors and densities are supported. And a plurality of them may be provided. That is, for example, the recording mode of the ink jet recording apparatus is not limited to the recording mode of only the mainstream color such as black, but may be a combination of a plurality of recording heads integrally formed, or a multicolor of different colors, or It can also be applied to an apparatus provided with at least one of full colors by color mixing.

In addition, in the above-mentioned embodiments, the ink is described as a liquid, but it is an ink which solidifies at room temperature or lower and softens or liquefies at room temperature, or in the ink jet recording system. 30 inks
Generally, the temperature is controlled in the range of ℃ to 70 ℃ to control the temperature of the ink so that the viscosity of the ink is within the stable ejection range. good. In addition, it is possible to prevent the temperature rise due to thermal energy from being positively used as the energy for changing the state of the ink from the solid state to the liquid state, or to use ink that solidifies when left standing for the purpose of preventing ink evaporation. However, in any case, when heat ink is liquefied by applying heat energy according to the recording signal and liquid ink is ejected, or when the ink reaches the recording sheet, it begins to solidify. It is also applicable when using an ink that has the property of being liquefied for the first time by energy.

The ink in such a case is described in JP-A-54-5.
As described in Japanese Patent No. 6847 or Japanese Patent Laid-Open No. 60-71260, a mode in which it is opposed to the electrothermal converter in a state of being held as a liquid or a solid in the concave portion or through hole of the porous sheet. Also good. The most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

Further, as the form of the above-mentioned ink jet recording apparatus, in addition to a form used as an image output terminal of an information processing equipment such as a computer, a form of a copying machine combined with a reader or the like, and a form of a facsimile machine having a transmission / reception function are provided. It may be something to take.

[0064]

As described above, the present invention is generated at the end of the recovery operation by forming the space portion having a wide cross-sectional area with respect to the ink flow path in the connecting portion between the cap member and the cap holding member. Even if a backflow of ink occurs, the backflow can be prevented because the ink is blocked by the space. Therefore, it is possible to prevent redeposition of the thickened ink on the recording means to maintain high image quality and to improve the safety and reliability of the apparatus.

Further, by disposing the ink absorber in the space, the ink suction space during the capping of the recording means can be kept in a wet state, and the ink ejection port of the recording means can be prevented from drying. . Further, when the recording means performs preliminary ejection of ink into the cap member prior to recording, it is possible to absorb and hold the ink by the ink absorber.

Furthermore, by using a cylinder as the cap holding member, the structure of the recovery means can be simplified, and by forming a space in the side wall of the cylinder, the shape of the cap member can be simplified and ensured. It becomes possible to hold the cap member on.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a connecting portion between a cap and a cap holder according to a first embodiment.

FIG. 2 is a perspective explanatory view of a recovery device.

FIG. 3 is a cross-sectional explanatory diagram of a recovery device.

FIG. 4 is a perspective explanatory diagram of an inkjet recording apparatus.

FIG. 5 is an explanatory view showing a connecting portion between the cap and the cap holder according to the second embodiment.

FIG. 6 is an explanatory view showing a connecting portion between a cap and a cylinder according to a third embodiment.

FIG. 7 is an explanatory view showing a connecting portion between a cap and a cylinder according to a fourth embodiment.

FIG. 8 is an explanatory diagram showing a connecting portion between a cap and a cylinder according to a fifth embodiment.

FIG. 9 is an explanatory diagram showing a connecting portion between a cap and a cylinder according to a sixth embodiment.

FIG. 10 is an explanatory view showing a connecting portion between a cap and a cylinder according to a seventh embodiment.

FIG. 11 is an explanatory view showing a connecting portion between a cap and a cylinder according to an eighth embodiment.

FIG. 12 is an explanatory diagram of a conventional inkjet recording device.

FIG. 13 is an explanatory view showing a conventional connecting portion between a cap and a cylinder.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Recording sheet 2 ... Sheet conveying means 2a ... Conveying roller 2b ... Pinch roller 3 ... Sheet pressing member 4 ... Platen 5 ... Carriage 6 ... Guide rail 7 ... Recording head 7a ... Ink cartridge 8 ... Guide means 9 ... Ejecting means 9a ... Discharge roller 9b ... Roller shaft 9c ... Discharge gear 10 ... Drive means 10a ... Drive motor 11 ... Recovery device 11a ... Wiper 11b ... Pump base 11c ... Rubbing member 11d ... Rubbing levers 11e, 11f ... Pump cam 11g ... Pump cam shaft 11h ... Piston 11i … Parallel pins 11j, 24… Cylinder 12… Bypass port 13a, 13b… Sidewall 14… Cap 14a… Ventilation port 14b… Ink suction space 14c, 15e… Ink flow path 14d… Flange 15… Cap holder 15a… Protrusion 15b… Coil spring 15c ... E-rings 15d, 24a ... Fitting part 16 ... Holder 17 ... Pump carriage 18, 18a, 18b ... 18c ... Rail arm 18d ... Rail dowel 19 ... Atmosphere release valve 20 ... Ink absorber 21 ... Suction tube 22 ... Backflow stop space 23 ... Joint 24b ... Ink suction pipe 24c ... Hook 25 ... Piston 26 ... Piston shaft 27 ... Cap stop

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Internal reference number FI Technical display location B41J 2/165 B41J 3/04 102 N (72) Inventor Hiroyuki Saito 3-30 Shimomaruko, Ota-ku, Tokyo No. 2 In Canon Inc. (72) Inventor Tetsuo Suzuki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Hiroyuki Kinoshita 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Non-Incorporated (72) Inventor Satoshi Sakawa 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Haruyuki Yanagi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Hideaki Kawakami 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (5)

[Claims] 1. An inkjet comprising: a recording unit that discharges ink to a recording material for recording according to image information; and a recovery unit that sucks ink from an ink discharge unit of the recording unit to perform recovery processing. In the recording apparatus, the recovery unit includes a cap member in which an ink flow path for covering the ink ejection unit of the recording unit is formed, a suction unit for sucking ink from the ink ejection unit through the cap member, and A cap holding member in which an ink flow path for holding the cap member is formed, and a space portion having a wide cross-sectional area with respect to the ink flow path is provided at a connecting portion between the cap member and the cap holding member. An inkjet recording device characterized by being formed. 2. The ink jet recording apparatus according to claim 1, wherein an ink absorber is arranged in the space. 3. The ink jet recording apparatus according to claim 1, wherein the cap holding member is a cylinder. 4. The ink jet recording apparatus according to claim 1, wherein the recording means includes an electrothermal converter for generating thermal energy for ejecting ink. 5. The ink jet recording according to claim 4, wherein the recording unit ejects the ink from the ejection port by utilizing film boiling generated in the ink by the thermal energy applied by the electrothermal converter. apparatus.