JPH06297715A - Recording head unit and ink jet recording apparatus using the same - Google Patents

Abstract

PURPOSE:To easily replace recording heads while keeping the accurate positional relation between the recording heads in an ink jet recording apparatus using a plurality of recording heads and to handle the ink tanks corresponding to the recording heads separately from the recording heads. CONSTITUTION:A plurality of recording heads IJU are received in the receiving parts demarcated by the unit outer wall plates 4001 and unit inner wall plates constituting a unit frame 4000 and, after the mutual positional relation of the recording heads is determined, the recording heads are fixed in the receiving parts and an upper housing 4506 and a side surface housing 4006 are fixed to the unit outer wall plate 4001. The replacement of the recording heads of the recording head unit thus constituted having a plurality of the recording heads is performed at every unit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording head unit having a plurality of inkjet recording heads and an inkjet recording apparatus using the unit.

[0002]

2. Description of the Related Art In an inkjet recording apparatus, a structure in which a recording head is detachably used has become popular in recent years. When the recording heads are detachable as described above, various technical advantages are generated in addition to various advantages. As one of them, there are known problems in mutual positioning between the recording heads when a plurality of recording heads are used. ing.

That is, when the individual recording heads are mounted on, for example, a carriage, it is necessary to maintain an accurate positional relationship between the respective recording heads.

To address the above problems, the present applicant has proposed a recording head mounting structure as disclosed in Japanese Patent Laid-Open No. 5-16339. Here, each recording head is biased to a predetermined reference surface for positioning and mounting, and the connector on the apparatus main body side is made displaceable so that unnecessary force does not act on the recording head side electric connection part connected to this. Thus, the positional accuracy of the recording head is ensured.

Further, the present applicant has proposed a recording head mounting structure as disclosed in Japanese Patent Laid-Open No. 3-55253 as a structure for solving the same problem.

Here, when a cartridge type head cartridge in which a recording head and an ink tank are integrally formed is mounted, the cartridge is moved relative to a connector on the main body of the apparatus, and in association with this movement. The positioning is also done. In addition, the user is allowed to perform such a mounting operation by a simple operation.

[0007]

However, there is some room for improvement in the conventional recording head mounting structure disclosed in each of the above publications.

First, when the recording head is mounted, the positioning operation of the recording head and the joining operation of the electrical contacts such as the connector are performed. In this case, the position setting of the connector on the main body side is compared with the positioning accuracy of the recording head. In some cases, the recording head may be twisted at the joining, or a force may be applied to deform the recording head. In such cases, in particular,
Since most of the recording head disclosed in JP-A-5-16339 has a plate-like chip shape, the deformation due to twisting or the like is relatively large. Further, in the structure disclosed in this publication, when vibration or shock acts on the connector on the apparatus main body side, the connector may be displaced and the recording head may be displaced. In any case, in the case of the above-described conventional mounting structure, there is a limit to the accuracy of mechanical positioning and its maintenance.

The above-mentioned deformation and displacement of the recording head appear as displacement of the ejection direction and ejection position when ejecting ink. These deviations are caused by the distance between the recording head and the recording medium such as recording paper (hereinafter referred to as the distance between papers).
Is increased by.

For example, in the apparatus disclosed in Japanese Patent Laid-Open No. 5-16339, the paper distance is 1.4 mm, and the distance from the recording head positioning reference to the recording head tip is 1.6.
When the length of the recording head is 30 mm and the length of the recording head is 30 mm, if the connector is displaced by 1 mm, the ink landing position on the recording medium is displaced by about 106 μm. Here, when the ejection port density of the recording head is 360 to 400 dpi, the pixel pitch is usually 70 to 60 μm, and therefore the deviation of the landing position is about 1 to 1.5 pixels.

Such a large deviation of the ink droplet landing position significantly deteriorates the image quality, and particularly when a plurality of recording heads respectively corresponding to a plurality of ink colors are used, a desired color is generated due to the above deviation. It cannot be reproduced and a high quality color image cannot be obtained. Further, a large displacement of the landing position may locally increase the amount of landed ink, and in such a case, so-called bleeding may occur in which the ink oozes out on the recording medium.

Second, the life of the recording head is generally shorter than the life of the recording apparatus main body. In such a case, the recording head needs to be replaced.
In the case of the configuration disclosed in Japanese Patent No. 339, it is relatively difficult and difficult for the user to replace the recording heads and accurately position the plurality of recording heads.

Thirdly, in the structure disclosed in Japanese Patent Laid-Open No. 3-55253, the user can replace the recording head with relative ease, but since the recording head and the ink tank are integrated, one of them has a problem. Even if there is not, there is a problem that both must be replaced. Also in this case, there is a mechanical limit in accurately arranging the plurality of recording heads. On the other hand, there is also known a configuration in which the misregistration is corrected by controlling the supply timing of the ink ejection signal, but it is necessary to give positional information to the recording head, which causes a problem that the recording head becomes expensive. .

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to maintain the positioning accuracy when mounting the recording head accompanying the replacement of the recording head and to mount the recording head. It is an object of the present invention to provide a recording head unit that can be easily performed and can individually convert ink tanks, and an inkjet recording apparatus using the unit.

[0015]

Therefore, in the present invention, a plurality of recording heads for ejecting ink and the plurality of recording heads are held while maintaining the positional relationship between the plurality of recording heads. A head holding member, a connecting member fixed to the head holding member, and provided on the outer surface thereof with electrical contacts for connecting electrical signals to each of the plurality of recording heads; A supply pipe holding member that holds the ink supply pipe fixed to the plurality of print heads for supplying ink to each of the plurality of print heads, corresponding to each of the plurality of print heads;
A recording head unit comprising: a recording head unit that is detachably used in an inkjet recording apparatus. In addition, a plurality of recording heads for ejecting ink, and a head holding member that holds the plurality of recording heads while maintaining the positional relationship between the plurality of recording heads,
A connection member that is fixed to the head holding member, and has an outer surface provided with an electric contact for connecting an electric signal to each of the plurality of recording heads, and fixed to the head holding member. A recording head unit having a supply pipe holding member for holding an ink supply pipe for supplying ink to each of the plurality of recording heads corresponding to each of the plurality of recording heads; An ink tank that is detachably connected to a tube, the recording head unit and the ink tank are detachably attached, and a movable carriage, and an electric contact of the recording head unit attached to the carriage can be connected. And a main body side connecting member provided with main body side electrical contacts.

[0016]

According to the above construction, the recording heads can be replaced for each unit, and the positional relationship between the plurality of recording heads is maintained during the replacement. That is, each newly installed recording head is not affected by the replacement operation. Further, the ink tanks corresponding to the respective recording heads can be individually replaced.

[0017]

Embodiments of the present invention will now be described in detail with reference to the drawings.

1 and 2 are a schematic sectional view and a schematic front view, respectively, showing a main part of a recording head used in an embodiment of the present invention.

As shown in FIG. 1, the recording head contains a substrate 100 (hereinafter referred to as a heater board) provided with a thermal energy generating element and a recording liquid (hereinafter referred to as ink) bonded to the substrate 100. The liquid chamber 7 and the substrate 1300 having an uneven portion forming the ink passage 8 are formed.
This substrate (hereinafter also referred to as a grooved top plate) 1300 integrally includes an orifice plate 400 provided with an ink ejection port (hereinafter also referred to as an orifice) 9 for ejecting ink communicating with the ink passage 8. I am.

The heater board 100 is a support substrate (hereinafter,
(Also referred to as a support) 300 is fixed by adhesion with an adhesive,
The grooved top plate 1300 has a heater board 1 so that the heat energy generating element arranged on the heater board 100 is included in the ink path 8 formed by this joining.
The orifice plate 400, which is temporarily adhered to No. 00 and has a grooved top plate, is arranged on the front end surface of the support substrate 300 like a front sag.

Ink is supplied from the ink supply path member 600.
Ink supply port 15 provided on the top of the grooved top plate 1300
It is supplied through 00. The ink supply path member 600 has a protrusion rod, and the protrusion rod is inserted into a through hole provided on the support substrate 300 and heat-crimped to fix the ink supply passage member 600 to the support substrate 300.

The gaps 10a, 10 between the ink supply path member 600 and the heater board 100, the grooved top plate 1300, etc.
The sealant is poured into the bonding region b, and the bonding region between the orifice plate and the front end surface of the support substrate, where a slight gap is provided so that the sealant can be enclosed.

In this embodiment, as shown in FIG. 2, the groove 3A may be any groove that can sufficiently encapsulate the sealing material. Further, the groove 3A is formed by the orifice plate 40.
It is important to form a space continuous with the gap between 0 and the ink supply path member 600. It is not preferable that the groove 3A is completely covered with the orifice plate 400 or is independent of the gaps 10a and 10b. This is because the flow path of the injected sealing material is cut off and good sealing cannot be achieved. The groove 3A formed on the front end surface of the support substrate 300 is formed by pressing in consideration of mass productivity.

The sealant is injected from a sealant injection port (not shown) in the upper portion of the ink supply path member 600 to seal a wire bonding portion (not shown) for transmitting an electric signal and at the same time as the orifice plate 400. Ink supply path member 6
The gaps 10a and 10b with respect to No. 00 are sealed, and the gap region between the orifice plate 400 and the front end surface of the support substrate 300 is completely sealed by passing through the groove 3A provided in the support substrate 300. Thus, in order for the sealing material to seal the gap without blocking the orifice 9, a proper thixotropy and a proper viscosity are required. That is, if the viscosity of the sealing material is too low, it will enter the ink passage 8 and the orifice 9 and cause clogging. On the other hand, if the viscosity is too high, the sealing material will not completely wrap around the orifice plate 400.

The viscosity of the sealing material used in this example is 1,
000 to 15,000 cps, more preferably 2,0
00-10,000 cps, most preferably 4,000
~ 10,000 cps.

As the sealing material, the heater board 100 made of a silicon wafer and the supporting substrate 30 made of a metal are used.
Good adhesiveness to the grooved top plate 1300 made of 0 and synthetic resin, the orifice plate 400, the ink supply path member 600 and the like is required. Further, in order to join a plurality of different materials having different thermal expansion coefficients, a soft material capable of absorbing the difference in thermal expansion due to the temperature environment,
Specifically, it is necessary to use a sealing material having a hardness of JIS standard A100 or less.

On the other hand, the encapsulating material also has a function of covering and protecting the wire bonding portion, and therefore must be a material that does not corrode the aluminum wire bonding portion and the aluminum electrode. In order to prevent corrosion on the electrodes and wire bonding, C in the encapsulant is used.
The concentration of impurity ions such as l ⁻ and Na ⁺ is preferably 30 ppm or less.

Such a material is also required to have such properties that it is excellent in ink resistance, particularly solvent resistance and alkali resistance, since it locally contacts the ink. Moreover,
It must also have low permeability to oxygen, nitrogen, and water vapor.

FIG. 3 is an exploded perspective view of the recording head shown in FIGS. The recording head of this example will be described in more detail with reference to FIG.

In FIG. 3, a substrate 100 made of Si is provided with a plurality of rows of electrothermal conversion elements (discharge heaters) as heat energy generating elements, and electrical wiring such as Al for supplying electric power thereto. And are formed by a film forming technique. Film boiling occurs in the ink due to the heat generated by the electrothermal conversion element, and the ink is ejected by the generation of bubbles due to the film boiling. The wiring board 200 has wirings (for example, connected by wire bonding) corresponding to the wirings of the heater board 100, and pads located at the ends of the wirings and receiving electric signals from the main body device.

As described above, the grooved top plate 1300 has a groove for forming a partition wall for partitioning a plurality of ink passages, a common liquid chamber for storing ink supplied to each ink passage, and the like. An ink supply port 150 that has the ink supplied from the ink tank and is introduced into the common liquid chamber described above.
0 and an orifice plate 400 having a plurality of ejection openings corresponding to the respective ink paths are integrally provided. Polysulfone is preferable as the integral molding material, but other molding resin materials may be used.

The support 300 supports the back surface of the wiring board 200 on a flat surface and is made of a metal such as Al. The presser spring 500 has an M-shape and presses a portion of the top plate corresponding to the common liquid chamber at the center of the M-shape with a light pressure and at the same time, the front slant portion 501.
Then, the portion corresponding to the ink path, preferably the region near the ejection port, is concentratedly pressed by the linear pressure. As for the heater board 100 and the top plate 1300, the foot portion of the presser spring has the hole 31 of the support body 300.
By engaging the back surface side of the support 300 through 21
When these are sandwiched, they are engaged and presser spring 50
The heater board 100 and the top plate 1300 are pressure-bonded and fixed to each other by the concentrated biasing force of 0 and the front slant portion 501. Support 3
The wiring board 200 is attached to 00 with an adhesive or the like. In addition, the recess 2400 of the support 300,
Reference numeral 2400 denotes positioning protrusions 2500 and 260, respectively.
The ink supply path member 600 is provided in the vicinity of 0.
Forms an ink conduit 1600 that is continuous with the above-described ink supply pipe 2200 as a cantilever with the supply pipe 2200 side fixed, and the fixed side of the ink conduit and the ink supply pipe 2200
A sealing ball 602 for ensuring the capillarity phenomenon is inserted. A filter 700 is provided at the end of the supply pipe on the tank side.
Is provided.

Since the ink supply passage member 600 is molded, the ink supply passage member 600 is relatively inexpensive, has high positional accuracy, and suppresses deterioration in manufacturing accuracy, and also has a cantilevered conduit 160.
By 0, the pressure contact state of the conduit 1600 to the ink supply port 1500 can be stabilized even in mass production.
In this example, a more complete communication state can be reliably obtained by simply pouring the sealing adhesive from the ink supply path member side under this pressure contact state. The ink supply path member 600
The fixing of the back side pin (not shown) of the ink supply path member 600 with respect to the holes 1901 and 1902 of the support body 300 is fixed to the hole 1 of the support body 300 as described above.
The support 30 is made to protrude through 901 and 1902.
This can be easily performed by heat-sealing the part of the No. 0 projecting to the back surface side.

FIG. 4 and FIG. 5 each show an embodiment of the present invention and are exploded perspective views of a recording head unit in which a plurality of recording heads are mounted. In FIG. 4, the housing member of the unit is shown. Omitted.

The recording head unit of this embodiment is equipped with four recording heads capable of ejecting inks of different colors, and the positional relationship between these recording heads can be accurately determined. The four recording heads may eject ink of the same color. In this case, high speed recording or gradation expression according to the number of ink droplets is possible, and ink of the same color but different density can be used. Gradation recording is possible even if each is ejected.

In FIG. 4, reference numeral 4000 indicates a unit frame. The unit frame 4000 includes a U-shaped outer wall plate 4001 and three inner wall plates 4002 that limit the head holding portion 4003 for housing each recording head.
The recording heads IJU described with reference to FIGS. 1 to 3 are housed in the respective head holding units 4003 with their ink ejection ports facing downward in the drawings. To position each recording head in the unit frame 4000, the reference surfaces provided in each recording head are abutted against the three-direction reference surfaces provided in each head holder, and then fixed with an adhesive or the like. In this case, the positional relationship between the reference surface and the orifice of each recording head IJU needs to be set with high accuracy.

Regarding the positioning of each recording head IJU, instead of the method using the above-mentioned reference plane, the recording head IJU may be positioned on an image by a TV camera or the like and then fixed by adhesion.

As described above, according to this embodiment, four recording heads are adhesively fixed to the unit frame, and the recording heads are exchanged for each unit. Therefore, four recording heads are recorded by the mounting operation at the time of exchange. The positional relationship between the heads does not shift. In addition, according to the configuration of this example in which individual recording heads are housed and fixed in the unit frame, compared to the configuration of the recording heads in which ink of different colors is ejected from the beginning by an integrated recording head. There is freedom in design. For example, recording head units of various specifications can be manufactured as described later with reference to FIG.

In FIG. 4, reference numeral 4005 is a porous member capable of absorbing ink, and is arranged between the orifice-arranged surfaces of adjacent recording heads IJU. This makes it possible to absorb ink adhering to the blade when wiping the orifice arrangement surface with the blade and prevent re-adhesion of different color ink to the adjacent orifice arrangement surface.

In FIG. 5, the upper housing 4506 and the side housing 4006 are each a unit frame 400.
It is fixed at 0. When the upper housing is fixed, a pair of pins 4504 (one of which is not shown) provided on the upper housing is inserted into a hole 4011 provided on the upper end surface of the outer wall plate 4001 of the unit frame 4000 so that the upper housing is fixed. The housing 4506 is positioned, and the projections (not shown) on the latch plates 4505 formed at both ends of the upper housing are latched by the latch plates 45 in the recesses 4010 formed in the outer wall plate.
It is fixed by being hooked together with the elastic biasing force of 05. The side housing 4006 is fixed to the unit frame in the same manner as the upper housing 4506 by using the pair of latch plates 4008 of the housing 4006 and the recess 4007 of the unit frame 4000.

A plurality of pads 4502 as electric contacts on the recording head IJU side are provided in a portion corresponding to the outer surface of the upper housing 4506, and each of the pads 4502 extends from the rear surface side of the upper housing 4506.
01 is connected. When the housing 4506 is fixed to the unit frame, the respective terminals 4501 come into contact with the corresponding connection pads on the substrate of the recording head.

The side housing 4006 has a hole 4 for inserting the ink supply pipe 2200 of the recording head IJU.
009 is formed.

The structure for electrically connecting a plurality of recording heads is not limited to the above example. For example, as shown in FIG. 6, a flexible printed circuit (FPC) in which a pad 4502 for connecting to the main body of the apparatus is printed is manufactured in advance, and as shown in FIG. It may be pressed against the surface of 4506. At this time, the electrical connection with each recording head is
A connector 4514 is connected to the FPC so as to correspond to the terminal 4513 of the FPC and the terminal 4515 of each recording head.
This is done by connecting and. Note that the connector 451
It is also possible to connect the FPC directly to the terminals of the recording head without using No. 4 by soldering, pressure welding or the like.

In each of the above-mentioned embodiments relating to the electrical connection portion, the connection pads provided on the housing are concentrated in the central portion of the housing so that the area of the connection pad is relatively small. This is because the stress acting on the pad at the time of connection is made large to ensure the connection. As described above, it is desirable that the stress exerted on the connection pad at the time of connection is large, but similarly, in order to maintain the reliability of the connection, it is desirable that the area of the pad is as large as possible. For this reason, for example, elements such as a shift register and a diode matrix forming a driver of the recording head are formed on a heater board or a printed wiring board of the recording head, which reduces the number of connection pads on the housing and reduces the number of individual pads. The area of the pad can be increased.

Further, as shown in FIGS. 8 and 9, a plurality of recording heads may be provided with connection pads for direct electrical connection with the main body side. The configuration for electrical connection between the recording head side connection pad and each of the plurality of recording heads can be omitted, and the cost of the entire recording head unit can be reduced. In this case, it is desirable to have a structure in which the pressure contact force is dispersed in the connection of the connection portion of each recording head to the main body side, and a uniform and sufficient pressure contact force is applied.

FIG. 10 is a perspective view showing the connection between the recording head unit shown in FIGS. 4 and 5 and each ink tank. Further, FIG. 11 is a cross-sectional view showing the connected state.

As shown in FIG. 10, the ink tank 6000 corresponding to each ink color has a joint portion 60.
The ink supply pipes 2200 of the corresponding recording heads are individually inserted into the 02 openings to connect to the recording heads. Also, when the ink tank 6000 is removed from the recording head, it is possible to individually remove each ink tank of each ink color.

With the above configuration, the ink tank 6000
When the ink is exhausted, it can be replaced with a new ink tank. As described above, since it is possible to replace each used ink tank, it is particularly effective in a color ink jet recording apparatus since waste ink can be reduced.

In FIG. 11, the supply pipe 2200 of the recording head IJU is inserted so that the filter 700 provided at its tip comes into pressure contact with the absorber 6003 in the ink tank 6000. Ink 6009 is stored in the ink chamber 6006.
Are filled, and the ink chamber 6006 and the partition wall 600 are
Part of the absorber 6003 in the front chamber 6004 separated by 5 is also filled with ink. The absorber 6003 can hold the ink by its capillary force, which prevents the ink from leaking from the joint portion 6002. The ink 6009 in the ink chamber 6006 passes through the slit 6008 and is supplied to the front chamber 6004.
In this supply, the air corresponding to the ink amount consumed by the ink supply to the recording head IJU side is the atmosphere communication port 6
It becomes possible by invading the inside of the ink tank through 013 and replacing the ink.

The configuration shown in FIG. 11 is one of the optimum ink tanks used in the present invention. That is, since there is a gap between the opening on the ink tank side and the supply pipe 2200 in the joint portion 6002,
This makes it difficult to apply a force that affects the positional accuracy of the recording head when the ink tank is inserted.

FIG. 12 shows an ink jet recording apparatus IJRA in which the recording head unit shown in the above embodiment can be mounted.
FIG.

In the figure, the forward and reverse rotations of the drive motor 5013 are transmitted to the lead screw 5004 via the drive force transmission gears 5011 and 5009, and rotate the lead screw 5004.
05 has a pin (not shown) that engages. As a result, the carriage HC is reciprocated in the longitudinal direction of the device.
Reference numeral 5002 denotes a cap that caps the front surface of each recording head in the recording head unit, and is used to perform suction suction recovery of the recording head through an opening in the cap by suction means (not shown). The cap 5002 can cover the ejection port surface of each moving recording head by the driving force transmitted via the gear 5008 or the like. Reference numeral 5017 is a cleaning blade, and 5019 is a member that allows this blade to move in the front-rear direction, and these are supported by a main body support plate 5018. The blade is not limited to this form,
It goes without saying that a known cleaning blade can be applied to this example.

The capping, cleaning, and suction recovery are configured so that desired processing can be performed at their corresponding positions by the action of the lead screw 5005 when the carriage moves to the home position, but at known timing. Any one can be applied to this example as long as a desired operation is performed.

The connection pad 4502 of the recording head unit mounted on the carriage HC is connected to the connection pad 5031 by rotating the connection plate 5030 provided on the carriage HC around a predetermined axis, and is electrically connected. Done. Since this connection does not use a connector or the like, unnecessary force does not act on the recording head unit.

FIGS. 13A and 13B are perspective views showing another example of the structure of the recording head unit, showing a state in which a part of the unit frame is removed.

The structure shown in FIGS. 13A and 13B is
An example is shown in which the recording heads are arranged so that their ejection port arrays are aligned with each other. In this way, the recording head unit in which a plurality of recording heads having the same structure are fixed and integrated in the unit frame and each ejects different ink, the ejection port array for each ink color can be arranged in various ways,
The degree of freedom in designing the recording device can be increased. In addition,
In the case of the structure shown in FIGS. 13A and 13B, the ink tank is mounted from below in the drawing.

FIG. 14 is a perspective view of an ink jet recording apparatus showing an example in which the ink tanks have different capacities.

As shown in the figure, the tanks 6000-A and 6000-B have different capacities.
Black (Bk) ink tank 600 for 000-A
0-B is filled with yellow (Y), magenta (M), and cyan (C) inks separated by partition walls. In general, Bk ink is also frequently used in color recording, and thus, replacement is not necessary frequently.

FIG. 15 is an external perspective view showing still another example of the recording head unit.

In the example shown in the figure, the connection pads 4502 are arranged on the same surface as the surface on which the ejection ports of the four recording heads are located. Further, the ink tank 6000 has a connection pad 450.
It is connected to the surface opposite to the surface on which 2 is provided.

FIG. 16 is a perspective view showing an ink jet recording apparatus using the recording head unit shown in FIG. 15. In the case of this configuration, the apparatus main body side electrical connection portion is on the lower surface side of the recording head unit in the figure. .

(Others) The present invention is provided with a means (for example, an electrothermal converter or a laser beam) for generating heat energy as energy used for ejecting ink, particularly in the ink jet recording system. The present invention brings about excellent effects in a recording head and a recording apparatus of the type in which the state of ink is changed by the heat energy. This is because such a system can achieve high density recording and high definition recording.

Regarding its typical structure and principle, see, for example, US Pat. Nos. 4,723,129 and 4740.
What is done using the basic principles disclosed in 796 is preferred. This method is a so-called on-demand type,
Although it can be applied to any of the continuous type, in particular, in the case of the on-demand type, it can be applied to the sheet holding the liquid (ink) or the electrothermal converter arranged corresponding to the liquid path. By applying at least one drive signal corresponding to the recording information and giving a rapid temperature rise exceeding nucleate boiling, heat energy is generated in the electrothermal converter, and film boiling is caused on the heat acting surface of the recording head. Liquid (ink) corresponding to this drive signal in a one-to-one correspondence
It is effective because bubbles can be formed inside. Due to the growth and contraction of the bubbles, the liquid (ink) is ejected through the ejection opening to form at least one droplet. It is more preferable to make this drive signal into a pulse shape because bubbles can be immediately and appropriately grown and contracted, so that liquid (ink) ejection with excellent responsiveness 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, further 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 specifications, US Pat. No. 4,558,333, US Pat. No. 4,558,333, which discloses a configuration in which a heat acting portion is arranged in a bending region.
The structure using the specification of No. 59600 is also included in the present invention. In addition, Japanese Unexamined Patent Publication No. 59-123670 discloses a configuration in which a common slit is used as a discharge portion of the electrothermal converter for a plurality of electrothermal converters, and an opening for absorbing a pressure wave of thermal energy is provided. The effect of the present invention is effective even if the configuration corresponding to the ejection portion is disclosed in JP-A-59-138461. That is, according to the present invention, recording can be surely and efficiently performed regardless of the form of the recording head.

Further, 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 which can be recorded by the recording apparatus. Such a recording head may have a configuration that satisfies the length by a combination of a plurality of recording heads or a configuration as one recording head integrally formed.

In addition, even in the case of the serial type as in the above example, the recording head fixed to the main body of the apparatus, or the electrical connection to the main body of the apparatus or the ink from the main body of the apparatus by being attached to the main body of the apparatus. The present invention is also effective when a replaceable chip-type recording head that can be supplied or a cartridge-type recording head in which an ink tank is integrally provided in the recording head itself is used.

Further, as the constitution of the recording apparatus of the present invention, it is preferable to add the ejection recovery means of the recording head, the preliminary auxiliary means and the like because the effects of the present invention can be further stabilized. Specifically, heating is performed by using a capping unit, a cleaning unit, a pressure or suction unit for the recording head, an electrothermal converter or a heating element other than this, or a combination thereof. Examples thereof include a preliminary heating unit for performing the discharge and a preliminary discharge unit for performing discharge different from the recording.

Regarding the type or number of recording heads to be mounted, 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. A plurality of pieces may be provided. That is, for example, the recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black, but it may be either the recording head is integrally formed or a plurality of combinations may be used. The present invention is also extremely effective for an apparatus provided with at least one of full-color recording modes by color mixing.

In addition, in the above-described embodiments of the present invention, the ink is described as a liquid, but an ink that solidifies at room temperature or lower and that softens or liquefies at room temperature may be used. Or, in the inkjet system, it is common to control the temperature of the ink itself within the range of 30 ° C. or higher and 70 ° C. or lower to control the temperature so that the viscosity of the ink is within the stable ejection range. Sometimes, a liquid ink may be used. In addition, the temperature rise due to thermal energy is positively prevented by using it as the energy of the state change from the solid state of the ink to the liquid state, or in order to prevent the evaporation of the ink, it is solidified and heated in the standing state. You may use the ink liquefied by. In any case, by applying heat energy such as ink that is liquefied by applying heat energy according to the recording signal and liquid ink is ejected or that begins to solidify when it reaches the recording medium. The present invention can be applied to the case where an ink having a property of being liquefied for the first time is used. In this case, the ink is
JP-A-54-56847 or JP-A-60-7
As described in Japanese Patent No. 1260, it may be configured to face the electrothermal converter in a state of being held as a liquid or a solid in the concave portion or the through hole of the porous sheet. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

In addition, as the form of the ink jet recording apparatus of the present invention, besides the one used as an image output terminal of information processing equipment such as a computer, a copying apparatus combined with a reader or the like, and a facsimile apparatus having a transmission / reception function can be used. It may be a form or the like.

[0071]

As is apparent from the above description, according to the present invention, the recording heads can be exchanged for each unit, and the positional relationship between a plurality of recording heads can be maintained during the exchange. It That is, each newly installed recording head is not affected by the replacement operation. Further, the ink tanks corresponding to the respective recording heads can be individually replaced.

As a result, it is possible to easily replace the recording head while maintaining the positional accuracy when replacing the recording head, and it is possible to use the ink economically.

[Brief description of drawings]

FIG. 1 is a sectional view showing a main part of a recording head according to an embodiment of the invention.

FIG. 2 is a front view of the main part of the recording head shown in FIG.

FIG. 3 is an exploded perspective view of the recording head shown in FIGS. 1 and 2.

FIG. 4 is an exploded perspective view showing a recording head unit including a plurality of recording heads shown in FIGS. 1 to 3 excluding a housing thereof.

FIG. 5 is an exploded perspective view of the recording head unit.

FIG. 6 is a plan view showing a flexible printed circuit board used in a recording head unit according to another embodiment of the present invention.

7 is a perspective view of a recording head unit in which the flexible printed circuit board shown in FIG. 6 is used for its electrical connection portion.

FIG. 8 is a perspective view showing another example of the configuration of the electrical connection portion of the recording head unit according to the invention.

FIG. 9 is a perspective view showing still another example of the configuration of the electrical connection portion of the recording head unit according to the invention.

FIG. 10 is a perspective view for explaining the connection between the recording head unit shown in FIGS. 4 and 5 and an ink tank.

11 is a cross-sectional view showing details of the connection shown in FIG.

FIG. 12 is a perspective view showing an inkjet recording apparatus using the recording head unit shown in FIGS.

13A and 13B are perspective views showing another example of the arrangement of the recording heads in the recording head unit.

FIG. 14 is a perspective view of an ink jet recording apparatus using another ink tank configuration.

FIG. 15 is a perspective view showing another example of the recording head unit according to the present invention.

16 is a perspective view of an ink jet recording apparatus using the recording head unit shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electrothermal conversion element 7 Liquid chamber 8 Ink passage 9 Discharge port (orifice) 100 Heater board 200 Printed circuit board 300 Support substrate 400 Orifice plate 600 Ink supply passage member 2200 Ink supply pipe 4000 Unit frame 4001 Unit outer wall plate 4002 Unit inner wall plate 4006 side housing 4009 hole 4501 terminal 4502 connection pad 4506 upper housing 4514 connector 5030 connection plate 5031 connection pad 6000,6000-A, 6000-B ink tank IJU recording head HC carriage

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location 9113-2C B41J 29/00 C (72) Inventor Eiichiro Shimizu 3-30-2 Shimomaruko, Ota-ku, Tokyo No. Canon Inc. (72) Inventor Masahiko Hikuma 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Tsuyoshi Orikasa 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. In-house (72) Inventor Seiichiro Karita 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (6)

[Claims] 1. A plurality of recording heads for ejecting ink, a head holding member for holding the plurality of recording heads while maintaining a positional relationship between the plurality of recording heads, and a head holding member for the head holding member. A plurality of recording heads that are fixed to the head holding member, and a connection member that is fixed to the head holding member and that is provided with electrical contacts for connecting electric signals to each of the plurality of recording heads. A recording head unit comprising: a supply pipe holding member that holds an ink supply pipe for supplying ink to each of the plurality of recording heads, the recording head unit being detachable in an inkjet recording apparatus. A recording head unit characterized by being used. 2. The recording head unit according to claim 1, wherein the electrical contacts are formed on a flexible printed circuit board in which the contacts are arranged in advance, and the board is joined to the connecting member. . 3. The recording head according to claim 1, wherein each of the plurality of recording heads uses thermal energy to generate bubbles in the ink, and ejects the ink as the bubbles are generated. Recording head unit. 4. A plurality of recording heads for ejecting ink, a head holding member for holding the plurality of recording heads while maintaining a positional relationship between the plurality of recording heads, and a head holding member for the head holding member. A plurality of recording heads that are fixed to the head holding member, and a connection member that is fixed to the head holding member and that is provided with electrical contacts for connecting electric signals to each of the plurality of recording heads. A recording head unit including a supply pipe holding member that holds an ink supply pipe for supplying ink to each of the plurality of recording heads, and a detachable connection with the ink supply pipe. An ink tank, a recording head unit and the ink tank that are detachably mounted, and a movable carriage, and the recording mounted on the carriage. An ink jet recording apparatus main body side connecting member which is disposed said electrical contacts can be connected body side electric contacts of the head unit, characterized in that comprises a. 5. The ink jet recording apparatus according to claim 4, wherein the electric contacts are formed on a flexible printed circuit board in which the contacts are arranged in advance, and the board is joined to the connecting member. . 6. The recording head according to claim 4, wherein each of the plurality of recording heads uses thermal energy to generate bubbles in the ink, and ejects the ink as the bubbles are generated. Inkjet recording device.