JPH10119285A - Ink jet recording head and ink jet recording device having the head mounted thereon - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the quality of highly precise color images by forming ink flow conduits and ink liquid chambers through joint of a substrate and a roof, and forming an recess for separating rows of ink ejection ports, and allowing the depth of the recess to be deeper than the ink ejection ports and ink flow conduits. SOLUTION: The roof 1 includes precisely worked ink flow conduits, ink liquid chamber frames, and ink ejection ports 5, and substrates 4 having resistive heating elements are processed and secured to the rood 1 through resilient members 3, then ribs 9 are provided on a recess 6 defined in its central portion. Besides, the rood 1 is formed such that resin or the like is molded integrally having ink ejection ports between two rows of the ejection ports and the deeper recess than the ink flow conduits, thereby allowing the ink ejection parts corresponding to each substrate of the rood 1 to deformed readily every substrate, and improving a contact state between the substrate 4 and the rood 1. Also, ribs 9 are made at both the recess 6 ends of the roof 1 so as to form the roof 1 with no ribs to easily be defined, as a result, the adhesion can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an ink jet recording head and a recording apparatus having the same.

[0002]

[Prior art]

(1) This type of ink jet recording apparatus is mainly connected to a word processor or a personal computer, and is used as a color printer or as a facsimile, a copying machine or the like in most cases.

Conventionally, as an ink jet recording head for a color printer, each color (black, yellow, magenta, cyan) is allocated by dividing an ink ejection portion in one head, and the number of nozzles per color is small. But,
One-head type, characterized by low cost; Independent head for each color, which can increase the number of nozzles per color, but increases the number of nozzles per color. The discharge unit is roughly classified into three types in which a discharge unit is incorporated into one base to form one set head unit.

In the one-head split type, since the ejection openings of each color are formed in one orifice plate, the accuracy of assembly can be excluded only by the processing accuracy. Therefore, the positional accuracy of the ejection openings of each color is good. It is advantageous for miniaturization because there is little misalignment in printing and the number of parts is small.

[0005] In the type in which a plurality of heads are arranged, the components of each head can be shared, and the head itself has a simple structure, so that it is easy to manufacture. However, since a plurality of heads are arranged, the overall size of the head section is large and heavy.

In the head unit type assembly, the orifice plate of each color measures the displacement of the ink droplet ejected from the ejection port, corrects the displacement, and is accurately assembled to the base. It is easy to print because the head is integrated as a combined head even when the head is replaced, and the number of ejection ports for each color can be increased, so that printing can be performed at high speed.

Further, the wiring board having the connection pads of the head is fixed to components other than the ink container or the top plate. The method of fixing the top plate and the substrate on which the resistive heating element is formed also uses bonding or a spring, and in the spring method, the top plate is placed on the substrate on which the resistive heating element fixed on the base plate is formed. And put a spring over it.

In the future, in order to further reduce the size and increase the speed of recording, which are demanded as ink jet recording heads for color printers, two types of heads, the above-described one-head division and combined head unit type, are expected.

(2) On the other hand, this type of ink jet recording system at present is easy to realize a compact, lightweight and inexpensive apparatus as compared with other systems, and has low noise during recording and can record on plain paper. Therefore, in recent years, low cost printers have become mainstream. Among them, the bubble jet method is easy to arrange a large number of ink ejection ports of an ink jet recording head at a high density, and is a method of low energy consumption in electric driving, so many products using this method are used. Is being offered to the market.

[0010] At present, there are roughly the following two types of ink supply modes in this type of ink jet printing apparatus. That is, first, while mounting an ink jet recording head on a carriage, a large-capacity ink tank is disposed at a predetermined position of the apparatus main body, and ink is supplied from the ink tank to the ink jet recording head via an ink tube. It is a method of supplying.

When this method is adopted, the operating cost is very low, but the life of the ink jet recording head itself is required to be substantially the same as or longer than the printing apparatus used by the ink jet recording head. In addition to the configuration described above, the material and the like need to be devised, and as a result, the cost of the inkjet recording head itself tends to be high.

On the other hand, as a second method, there is an ink jet unit in which an ink tank and an ink jet recording head are integrated, which can be attached to and detached from a carriage. When this method is employed, the tubes are hardly routed, the ink exchange process is easy, and the apparatus can be downsized. However, when the ink in the ink tank runs out, the ink tank and the ink jet recording head are both replaced, so that the operating cost is high. In particular, in such a case, the ink jet recording head having at least the life until the ink is used up is wastefully discarded, which is not preferable from the viewpoint of ecology and the like.

As one configuration for solving the problem of the above-mentioned second system, an ink jet recording head and an ink tank which can be separated and which can be attached to and detached from a carriage are disclosed in, for example, Japanese Patent Application Laid-Open No. No. 4953, and the like. Such a configuration is effective for solving the above-mentioned problems such as an increase in operating cost since the ink jet recording head and the ink tank can be exchanged independently of each other.

[0014]

[Problems to be solved by the invention]

(A) However, the following problem also occurs in the one-head in-part division format described in (1) above. That is, since the plurality of resistive heating elements on one substrate on which the resistive heating elements are formed are divided for each color, the number of resistive heating elements allocated per color is reduced, and high-speed printing cannot be performed.

The head unit type of the above item (1) also has the following problems. In other words, when performing high-definition color image output, it is necessary to reduce the deviation of the landing points of the ink droplets of each color, so that the assembling of the orifice plate for each color requires higher precision, and the orifice plate is joined to the base. A method that does not shift the position as much as possible is required. Inevitably, the time required for the assembling becomes long, and an expensive assembling apparatus must be used. In addition, since several heads are basically arranged, the size of the head unit becomes large, and the number of parts increases.

Further, since the wiring board having the connection pads is fixed to a component other than the ink container or the top plate, the head and the ink container cannot be separated and the disposable head is used, or the fixed component is attached. Therefore, the number of parts was increasing. The spring method is also easy to assemble the top plate and the substrate on which the resistive heating element is formed.
Since the parts were assembled on the base plate, the number of parts increased, and the assembly time was long. Furthermore, in order to assemble a substrate on which a plurality of resistive heating elements are formed on a base plate, the size increases and it is difficult to assemble.

(B) Further, in a configuration in which the ink jet recording head unit is attached to and detached from the carriage described in the above item (2) and the ink jet recording head and the ink tank can be separated, the following points are set forth. It was necessary to design the ink jet recording head and the ink jet unit while paying attention to the above.

That is, it is possible to prevent a decrease in electrical reliability due to the adhesion of ink or paper powder, to improve the accuracy of attaching an ink jet recording head or the like to a carriage, to increase the ease of replacing an ink tank or the like, and to perform color recording. To increase the mutual alignment accuracy of the respective ink jet recording heads, and to facilitate manufacture of the ink jet recording heads and the like.

Therefore, an object of the present invention has been made in view of the above problems (a) and (b).
For item (a), it is possible to improve the image quality of a high-definition color image by preventing printing misregistration of each color due to ink droplet landing point accuracy and the like, and to enable high-speed recording and a small head size.
An object of the present invention is to provide a highly reliable ink jet recording head having a small number of components.

The present invention provides an ink jet recording head, an ink jet unit, and an ink jet recording apparatus which are inexpensive, can be miniaturized, and have high operability and reliability. Further, even when an ink tank or the like is attached or detached while being mounted on an ink jet recording apparatus, an ink jet recording head and an ink jet unit capable of recording a high-quality image without causing a positional shift of each head affecting color recording. And an ink jet recording apparatus.

[0021]

Means for Solving the Problems The present inventors have conducted intensive studies in order to solve the above problems, and as a result, have reached the present invention. That is, a top plate on which two ink flow channel groups for forming ink flow channels, two ink liquid chamber frames and ink introduction paths are formed, and a plurality of ink ejection ports are arranged in two rows, Two substrates on each of which a plurality of resistive heating elements for individually discharging ink are formed corresponding to the two ink discharge port arrays, and the substrate and the top plate are pressed and fixed for each substrate. An ink jet recording head having the ink flow path and the ink liquid chamber formed by joining the substrate and the top plate, wherein the ink ejection port array of the top plate is provided. A groove separating the ink ejection port array is formed therebetween, and the depth of the groove is deeper than the ink ejection port and the ink flow path.

In the ink jet recording head, an electrical connection surface is disposed within ± 5 ° in a direction perpendicular to the ink discharge direction of the head, and the ink discharge surface is closer to the recording material than the electrical connection surface. It may be configured to protrude at least 5 mm or more.

[0023]

According to the structure of the present invention as described above, the following effects can be obtained. (A) In an ink jet recording head, a plurality of substrates having resistive heating elements are pressed and fixed by an elastic member to a top plate on which ink channel grooves, ink liquid chamber frames and the like are formed, and the top plate is accurately integrated. In addition, by precisely processing the discharge ports and the like with a laser beam with reference to the reference surface built in the top plate, it is possible to prevent printing misregistration of each color and improve printing quality and image quality. In addition, the number of parts is small, the assembling work can be shortened, the reliability and yield of the product can be improved, the size can be reduced, and a small printer can be realized. Furthermore, high-speed printing is possible because a plurality of substrates having resistive heating elements can be used. By providing a groove (recess) deeper than the ink flow path between the ink discharge port arrays, each substrate can be brought into close contact with the top plate.

(B) The reliability is improved by not forming the ink ejection surface on the same surface as the ink supply surface and the electrical connection surface. ° Rotational position enables cost reduction by sharing parts, and the ink supply part is connected in the ink ejection direction, so that the load applied to the head when attaching and detaching the ink tank is evenly applied to the outside of the ink row. Receiving the information also makes it possible to prevent a head displacement that affects color printing.

[0025]

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

(First Embodiment) FIG. 1 schematically shows the structure of an ink jet head 10 (in this embodiment, ink ejection ports are arranged in two rows) according to a first embodiment of the present invention. It is a perspective view. In FIG. 1, reference numeral 1 denotes a top plate in which the ink flow channel, the ink liquid chamber frame, and the ink discharge port are opened in advance, 2 denotes a wiring board that electrically connects the substrate on which the resistive heating element is mounted and the carriage side, 3 is an elastic member for pressing and fixing the substrate having the resistive heating element against the top plate 1,
Reference numeral 5 denotes an ink ejection opening formed in the top plate 1, reference numeral 6 denotes a concave portion provided in the center of the top plate 1, and reference numeral 9 denotes a rib provided in the concave portion 6.

In the configuration of the two-row array of this embodiment, the two-row side can be prepared for the one-row side and the object, and the ink introduction paths can be collectively collected at one place. The top plate is easy to make and easy to assemble.

FIG. 2 is an exploded perspective view showing the detailed configuration of the ink jet head 10 shown in FIG. 1, and is a schematic diagram drawn so that the outline of the component configuration and assembly can be understood.
In the figure, reference numeral 4 denotes a substrate having the above-described resistive heating element,
The wiring board 2 is electrically connected by TAB mounting.

FIG. 3 is a cross-sectional view of the ink jet head 10 shown in FIG. In the drawing, reference numeral 7 denotes an ink introduction path for guiding ink from an ink container to an ink liquid chamber. Ink passes from the ink container 11 through the ink introduction path 7,
The liquid enters the liquid chamber 8 formed by the top plate 1 and the substrate 4 having the resistive heating element, and further enters the ink flow path having the resistive heating element from the liquid chamber 8. Then, film boiling is caused to the ink by the thermal energy of the resistive heating element, and the ink is ejected from the ejection port 5.

The liquid chamber 8 is formed by the top plate 1 and the substrate 4 having the resistive heating element, and is sealed with a sealant in order to completely seal the space therebetween and to prevent ink leakage. Also,
The sealant is also used at the TAB connection between the substrate 4 having the resistive heating element and the wiring board 2 to prevent and protect the ink from adhering.

The top plate 1 is formed by integrally molding a resin or the like.
The ink discharge port 5, the ink flow path groove, the ink liquid chamber frame, and the ink introduction path 7 are processed by molding or laser processing. Since the ink discharge ports 5 and the ink flow path grooves need to be processed with high precision, they are preferably formed by laser processing.

In addition, it is preferable that the ink ejection port 5 has a smaller angle variation in the ink ejection direction for each ink row, even if the distance between the ink ejection port 5 and the recording medium changes. Since the landing position does not change, electrical correction is basically unnecessary, resulting in an electrically simple configuration. Therefore, the processing accuracy is improved, and the surface treatment around the ink discharge port 5 is made uniform. For these integrally molded products, it is necessary to select a material that is hardly affected by moldability and ink. As a specific material, polysulfone is desirable, but other molding materials may be used.

The substrate 4 having the resistive heating elements is used for recording by causing film boiling due to thermal energy to the ink. The resistive heating elements are arranged in a plurality of rows on a Si substrate. The wiring is a substrate on which a shift register and a driving transistor are built in, in order to reduce the number of TAB pads, in which an electrical wiring of Al or the like for supplying electric power is formed by a film forming technique. The substrate 4 and the top plate 1 need to be assembled with high precision.

The wiring board 2 connects the substrate 4 to an electric signal from the main body printer (inkjet recording apparatus). One side is connected to the substrate 4 by TAB, and the other side receives the electric signal from the main body printer. It has a connection pad for receiving. The connection pad portion is accurately fixed to the top plate 1 by bonding. For this reason, the head can be handled as one unit, and assembling is easy and recycling is easy.
In addition, the substrate 4 having the resistive heating element is fixed to the top plate 1 by mechanical bias by the elastic member 3.

Then, as described above, the substrate 4 is
Therefore, the top plate 1 needs to be slightly deformed in order to completely contact the top plate 1. This is because it is impossible to make the contact surface between the substrate 4 and the top plate 1 completely flat in a single product state, and several μm
This is because a slight gap occurs.

Therefore, by providing a groove (recess) 6 deeper than the ink discharge portion (ink discharge port and ink flow path) between the two discharge port rows of the top plate, each substrate of the top plate is provided for each substrate. Are easily deformed, and the contact state between the substrate and the top plate can be improved.

Further, in the present embodiment, the recess 6 of the top plate 1 is used.
Ribs 9 are provided at both ends of the top plate, and the top plate in the portion without ribs is slightly deformed to improve the adhesion.

That is, the present embodiment is suitable for a case where the top plate 1 and the substrate 4 are connected without any external force, and there is a gap at both ends.

When the ribs are provided at both ends of the concave portion, a gap may be formed at the center of the substrate. Therefore, after the substrate and the top plate are pressed and fixed by an elastic member, a member that is a wedge larger than the width of the concave portion (groove) is inserted in the vicinity of the concave portion corresponding to the central portion of the substrate. By pressing the corresponding portion, the adhesion between the substrate and the top plate can be further increased. Here, the member serving as the wedge may be any material as long as it has a hardness equal to or higher than the material forming the top plate,
By using the same material as the top plate, it is possible to reduce the possibility that the balance of adhesion changes due to a temperature change.

In the present embodiment, when ink of different colors is used for each of the two rows of ink discharge ports, the recesses (grooves) provided between the above-described ink discharge port rows are used for cleaning the ink discharge port surfaces. Is also effective in preventing color mixing. Hereinafter, this will be described.

First, an ink jet recording apparatus equipped with such an ink jet head will be described with reference to FIG.

In the configuration shown in FIG.
Are moved in parallel on the lead screw 204 and the guide shaft 205 by the lead screw 204 interlocked with the carriage motor 203.

A print head 202 in which a head and an ink tank are integrated is fixed on the carriage 200, and ink ejected from the print head 202 is
In this case, an image is formed on a recording medium facing 02, that is, on a recording sheet 206 to form an image. The recording paper 206 is discharged in synchronization with printing by a discharge motor (not shown), a feed roller, a discharge roller, and a paper holding plate 209 that are linked thereto. The cap is capped by a cap (not shown) at the time of non-printing or at the time of the recovery operation.

The wiper 110 is connected to the print head 202.
This is for cleaning the face surface (ink ejection surface), and removes ink and foreign matter adhering to the face surface after the recovery operation or during printing. Usually, this wiper 110 is
It has receded to a position where it does not come into contact with the head, moves forward only during wiping, and comes into contact with the face surface of the head 202 that has moved with the carriage 200.

Next, the wiping operation when the ink jet head unit is attached to a recording apparatus will be described below.

When wiping is performed, the wiper 110, which is a cleaning member, advances to the wiping position in synchronization with the head moving with the carriage, as shown in FIG.
It enters the concave portion 6 of the top plate 1. Then, as the carriage moves, the face surface on one side of the top plate 1 is wiped. When the carriage moves in the opposite direction, the wiping operation is performed in the same manner as described above, whereby the opposite face surface is also wiped.

That is, as shown by arrows in FIG. 5, since the wiping directions of the two nozzle rows are different, it is possible to prevent waste of ink due to color mixing and the accompanying preliminary ejection. Further, since wiping is performed only when necessary for each nozzle row, it is not necessary to improve the durability of the face surface more than necessary. In particular, in the case of a head having a recording ink on one side and a processing liquid which reacts with the ink to improve the print quality and water resistance, etc., a reaction occurs when the ink comes into contact with the processing liquid. It is desirable to change the wiping direction on the member and as described above.

Furthermore, during wiping, the face surface is wiped after the ridge line of the concave portion 6 comes into contact with the wiper 110, so that unnecessary ink attached to the wiper 110 is removed and held in the concave portion 6. For this reason, wiper 1
10 can always wipe the face surface in a clean state.

Further, it is more preferable that the ridge line of the concave portion 6 is chamfered as shown in FIG. The chamfer serves as an intrusion guide for the wiper 110 and also prevents the edge of the wiper 110 from being damaged. FIG.
In the above, the chamfer was used, but it may be rounded.

In FIG. 6, reference numeral 11 denotes an area where the blade is not fixed and can be deformed (free length), reference numeral 12 denotes an amount of penetration into the face surface, and t denotes a thickness of the blade. The wiping ability of the face is largely determined by the above parameters.
That is, as the free length is longer, the penetration amount is smaller, and the thickness is thinner, the pressing force of the blade against the face surface becomes weaker, and conversely, the pressing force increases. At this time, if the pressing force is too weak, the ink will naturally be left unwiped, and if it is too strong, the blade will be deformed too much, resulting in unwiped and deteriorated face surface durability.

According to experiments by the present inventors, for example, the material of the blade: urethane, free length: 4 mm, thickness: 0.3 m
m, the optimal penetration range is 0.4-1.5 mm
Was in the range. Further, since the amount of penetration is determined by the positional relationship between the head and the blade, it is desirable to have an optimum range of 0.4 mm or more in consideration of variations.
According to the experimental results in which the above parameters were changed, the blade thickness was 0.15 mm or more and the penetration amount was 0.2
mm or more is desirable.

The recess 6 of the top plate 1 is
In order not to prevent the penetration of 10, it is preferable that the depth (A) is 0.3 mm or more and the width (B) is 0.5 mm or more as shown in FIG.

In general, a head having a water-repellent region for preventing the ejection angle from being bent due to ink leakage on the face surface and a hydrophilic region for trapping ink droplets attached to the face surface is known. However, such a top plate 1
FIG. 7 shows a preferred embodiment of a head having a hydrophilic portion 13 on the face surface of the head.

The operation of the wiper 110 according to the present embodiment is shown in FIG.
In the same manner as in the embodiment shown in FIG. 1, the process is performed from the center of the top plate 1 toward the outside of each nozzle row. In this case, as shown in FIG. 7, the hydrophilic portion 13 is provided outside each nozzle row (top plate end). That is, since the hydrophilic portion 13 in which foreign matter such as fixed ink easily accumulates is located downstream of the nozzle in the wiper direction, there is no fear that the wiper 110 pushes foreign matter into the nozzle. In the present embodiment, the hydrophilic portion 13 is provided for both of the two nozzle rows, but a configuration in which the hydrophilic portion 13 is provided for only one of the nozzle rows may be employed.

(Second Embodiment) FIGS. 8 to 10 show an ink jet recording head 10 according to a second embodiment of the present invention, corresponding to FIGS. 1 to 3 of the first embodiment, and an ink jet cartridge equipped with the head. Show. In each figure, the main configuration is substantially the same as in the first embodiment,
The same (corresponding) components as those in FIGS.

Hereinafter, the second embodiment will be described, including the overlap with the first embodiment. 1 is a top plate in which an ink flow path groove, an ink liquid chamber frame, and an ink discharge port are opened in advance, 2 is a wiring board that electrically connects a substrate having a resistive heating element to the carriage side, and 3 is a resistance board. The elastic member 5 for pressing and fixing the substrate having the heating element to the top plate 1 is an ink ejection port opened in the top plate 1. In the two-row array of this example, two rows can be formed symmetrically to the one-row side, and the ink introduction paths are collectively collected at one location in the center, so that the top row is compared to the three or more rows. The board 1 is easy to make and easy to assemble. Furthermore, the components in each row are basically the same,
It is also advantageous in terms of cost.

FIG. 9 is a schematic diagram drawn so that the outline of the component configuration and assembly of the ink jet recording head 10 shown in FIG. 8 can be understood. Reference numeral 4 denotes a substrate having a resistive heating element, which is bonded to the metal plate 15. The wiring board 2 is electrically connected by TAB mounting. Further, the wiring board 2 is fixed to the metal plate 15 by bonding so that a bending force is not applied to the substrate 4 having the resistive heating element when the wiring board 2 is bent.

FIG. 10 is a sectional view of the ink jet recording head 10 shown in FIG. Reference numeral 7 denotes an ink introduction path for guiding ink from the ink container to the ink liquid chamber.

From the ink container, the ink passes through the ink introduction path 7 and enters the ink liquid chamber 8 formed by the top plate 1 and the substrate 4 having the resistive heating element. The ink enters the ink flow path groove 14 having the resistive heating element from the liquid chamber 8, causes the ink to cause film boiling by thermal energy of the resistive heating element, and discharges the ink from the discharge port 5.

The ink liquid chamber 8 is formed by the top plate 1 and the substrate 4 having a resistive heating element. The space between them is completely sealed and sealed with a sealant to prevent ink leakage. Further, the sealing agent is used for the T between the substrate 4 having the resistive heating element and the wiring substrate 2.
It is also used at the AB connection to prevent and protect ink adhesion.

The top plate 1 is integrally formed, and the ink discharge ports 5, the ink flow grooves 14, the ink liquid chamber frame and the ink introduction path 7 are processed by molding or laser beam processing. The ink discharge ports 5 and the ink flow grooves 14 need to be processed with high precision. Ink ejection ports 5 are designed such that the smaller the variation in the angle of the ink ejection direction in each ink row, the smaller the variation in the angle between the ink ejection ports 5 and the recording medium. Does not change, electrical correction is basically unnecessary, and the configuration is electrically simple. Therefore, the processing accuracy is increased, and the surface treatment around the ink discharge port 5 is made uniform. For these integrally molded articles, it is necessary to select a material that is hardly affected by moldability and ink. As a specific material, polysulfone is desirable, but other molding materials may be used.

The substrate 4 having a resistive heating element is used for recording by causing a film boiling due to thermal energy to the ink. The resistive heating element is arranged in a plurality of rows on a Si substrate. The wiring is a substrate in which a shift register and a driving transistor are incorporated in order to reduce the number of TAB pads by forming an electrical wiring of Al or the like for supplying electric power by a film forming technique. The substrate 4 has an ink ejection port 5
If the position is not correct, normal ejection cannot be performed, and it is necessary to assemble with the top plate 1 with high accuracy.

The wiring board 2 connects the board 4 to an electric signal from the main body printer.
AB, and the other has connection pads for receiving electric signals from the main body printer. The connection pad portion is accurately fixed to the top plate 1 by adhesion. Therefore, since the head can be handled as one unit, it is easy to assemble, and it is convenient for recycling. Further, the substrate 4 having the resistive heating element is fixed to the top plate 1 by mechanical biasing of the landing member 3.

FIG. 9 is a perspective view schematically showing an ink jet recording head unit having the ink jet recording head 10 of the embodiment of the present invention shown in FIG. The ink jet recording head 10 is directly fixed to the front of the ink container (tank) 11 in the mounting direction with respect to the ink jet recording apparatus, and is configured to be mountable to the ink jet recording apparatus.

(Third Embodiment) Prior to the detailed description of this embodiment,
First, the basic configuration of an ink jet recording head to which the present invention is applied and its configuration requirements will be described, including some overlap with the above description.

The embodiment of the present invention is an ink-jet unit in which an ink tank and an ink-jet recording head can be attached to and detached from a carriage, respectively. ), (B) a portion that receives ink from an ink tank (hereinafter, referred to as an “ink supply portion”), (c) a portion that discharges ink (hereinafter, referred to as an “ink discharge portion”),
(D) Four main functional parts, a part for positioning the ink jet recording head with respect to the carriage (hereinafter referred to as a “positioning part”), are provided on each surface of the recording head.

Further, in the configuration of these four main functional parts, the reliability, image quality, and ease of replacement of the ink jet recording head and the ink tank are required for the ink jet recording head. It is desirable to consider the conditions.

If the ink supply unit or the electrical connection unit is provided on the same surface as the surface on which the ink ejection unit is provided, the mist of the recording ink ejected from the ink ejection unit is electrically A short circuit may occur due to ink mist conduction due to scattering at the connection part, or paper dust or the like adhering to the electrical connection part due to the short distance between the recording material and the electrical connection part may cause a poor electrical contact. And may cause.

When the ink jet recording head is replaced or the separated ink tank is replaced, the attaching / detaching force is applied to the carriage and the ink jet recording head. When the ink jet recording head moves due to such a load, an accurate position of the ink jet recording head cannot be ensured, so that an accurate landing position of the recording ink cannot be ensured, and the image quality is degraded. .

In the manufacturing process, it is necessary to assemble the positioning accuracy of the respective ink jet recording heads for performing color recording with high accuracy.

FIG. 11 shows an example of the configuration relating to the ink jet recording head and the ink tank of the third embodiment according to the present invention in consideration of the above conditions.

In the figure, reference numeral 100 denotes an ink jet recording head, and reference numerals 101, 102, and 103 denote an ink discharge portion, a holder, and an electrical connection portion of the ink jet recording head 100, respectively. Reference numeral 106 denotes an ink tank, which supplies ink by being connected to an ink supply pipe 105 arranged in a direction perpendicular to an ink ejection direction, that is, an electrical connection surface, in the holder 102 to which the inkjet recording head 100 is fixed. .

FIG. 12 is a diagram showing the configuration of the ink jet unit shown in FIG. 11 viewed from the ink discharge direction. , 101B; 1
03A and 103B. Here, 104C and 104D are the ink jet recording heads 100.
This is a positioning section provided at the corner of the ink jet recording head 100, and positions the ink jet recording head 100 in the X and Y directions with respect to a main body (not shown). The positioning in the Z direction is performed at 104B and 104A in FIG. Here, the groove 107 is provided in the ink ejection units 101A and 101A.
B, and the length is longer than the ink ejection section.

In this embodiment, the components of the recording head described above are arranged on the recording head so as to satisfy the following conditions. That is, by not forming the ink ejection surface on the same surface as the ink supply surface and the electrical connection surface, the mist of the recording ink ejected from the ink ejection portion is scattered to the electrical connection portion, and the ink mist generated by conduction is generated. Short-circuit can be prevented, and since the distance between the recording material and the electrical connection surface is large, electrical contact failure due to paper dust or the like adhering to the electrical connection surface can also be prevented.

Particularly, in this embodiment, since the electrical connection surface is arranged within ± 5 ° in the direction perpendicular to the ink ejection direction, and the ink ejection surface is arranged to protrude from the electrical connection surface by 5 mm or more, By using the step portion as an electrical connection portion of the printer main body carriage, the above-described effect as a wall for preventing ink mist and paper dust can be obtained.

Further, when the ink discharge units are arranged in two rows in the main scanning direction in order to perform color printing, the first row of the ink discharge units and the corresponding electrical connection surface are connected to the two rows.
By arranging the ink discharge units in the rows and the electrical connection surfaces corresponding thereto at positions rotated by 180 ° about the center of the two rows as the rotation center, it is possible to reduce costs by sharing parts.

Further, by providing a groove having a length longer than that of the ink ejection section between the two rows of ink ejection sections, it is also possible to prevent color mixing when the ink colors of the respective ink ejection sections are different. .

Then, the ink supply portions such as the separated ink tanks are pressed in the ink ejection direction and connected to each other, so that the load applied to the head when the ink tank is replaced or the like is evenly applied to the outer side of the ink row. This also makes it possible to prevent a head displacement that affects color printing.

[0079]

As described above, according to the present invention, (1) In an ink jet recording head, a plurality of substrates each having a top plate on which ink flow channel grooves and ink liquid chamber frames are formed and a resistive heating element are provided. Are fixed by pressure with an elastic member.The top plate is formed integrally with high precision, and the discharge ports and the like are processed with a laser beam with high accuracy based on the reference surface built in the top plate. It is possible to improve printing quality and image quality by preventing printing misalignment.Also, the number of parts is small, assembly work can be shortened, product reliability and yield can be improved, size can be reduced, and compact printers are possible. Become. Further, since a plurality of substrates having resistive heating elements can be used, high-speed printing is also possible.

By providing a groove (concave portion) deeper than the ink discharge portion (ink discharge port and ink flow path) between the two discharge port arrays on the top plate, each substrate is provided on each substrate of the top plate. The corresponding ink ejection portion is deformed, and the contact state between the substrate and the top plate can be improved. (2) Further, the reliability is improved by arranging the ink ejection surface so as to protrude at least 5 mm or more without forming the ink ejection surface on the same surface as the ink supply surface and the electrical connection surface. By arranging at a position rotated by 180 ° about the center point of the ink ejection row of the row as a rotation center, it is possible to reduce the cost by sharing parts, and furthermore, the ink tank is pressed and connected in the ink ejection direction. Thus, the load applied to the head when the ink tank is attached and detached is evenly applied to the outside of the ink row, so that it is possible to prevent the head from being displaced, which affects color recording.

(3) Further, by providing a recess near the center of the top plate of the head having a plurality of nozzle rows, into which the wiper member can enter, it is possible to prevent color mixing and unwiping, and also to remove the wiper. The number of times can be minimized, which also improves the durability of the face surface and the wiper.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically illustrating a configuration of an inkjet head according to a first embodiment of the present invention.

FIG. 2 is an exploded perspective view showing a detailed configuration of the inkjet head of FIG. 1;

FIG. 3 is a sectional view showing the internal configuration of the ink jet head of FIG. 1;

FIG. 4 is a perspective view schematically showing a configuration of a head unit having the inkjet head of FIG. 1;

FIG. 5 is an explanatory diagram showing an operation at the time of wiping according to the first embodiment;

FIG. 6 is an explanatory diagram showing an operation at the time of wiping according to the first embodiment;

FIG. 7 is an explanatory diagram showing an operation at the time of wiping according to the first embodiment;

FIG. 8 is a schematic external perspective view of an ink jet recording head according to a second embodiment.

9 is an exploded schematic view of the inkjet recording head of FIG.

FIG. 10 is a cross-sectional view illustrating an internal configuration and an ink flow path of an ink jet recording head according to a second embodiment.

FIG. 11 is an external perspective view of an ink jet recording head unit according to a third embodiment.

12 is a configuration diagram viewed from an ink ejection direction side in FIG. 11;

FIG. 13 is a perspective view illustrating a configuration of an inkjet recording apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Top plate 2 Wiring board 3 Elastic member 4 Substrate with resistive heating element 5 Ink ejection port 6 Top plate central recess 7 Ink introduction path 8 Ink liquid chamber 9 Rib 10 Ink jet head 11 Ink container 12 Joint seal 13 Hydrophilic part 14 Ink Channel groove 15 Metal plate 100 Ink jet recording head 101, 101A, 101B Ink ejection unit 102 Holder 103, 103A, 103B Electrical connection unit 104A, 104B, 104C, 104D Positioning unit 105 Ink supply pipe 106 Ink tank 107 Groove 110 Wiper ( Cleaning member) A Center of rotation

Continuation of the front page (72) Inventor Wataru Takahashi 3-30-2 Shimomaruko, Ota-ku, Tokyo Within Canon Inc. (72) Inventor Toshiaki Masuda 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Hajime Yamamoto 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Yasuo Kotaki 3-30-2 Shimomaruko 3-chome, Ota-ku, Tokyo Canon Inc. (72) Invention Person Akihiro Yamanaka 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc.

Claims (15)

[Claims] 1. A ceiling having two ink flow channel groups for forming ink flow channels, two ink liquid chamber frames and an ink introduction path, and a plurality of ink discharge ports arranged in two rows. A plate, two substrates on each of which a plurality of resistive heating elements for individually discharging ink are formed, corresponding to the two ink discharge port arrays, respectively, the substrate and the top plate for each substrate. An ink jet recording head comprising: two elastic members for pressing and fixing the ink passage, wherein the ink flow path and the ink liquid chamber are formed by joining the substrate and the top plate, An ink jet recording head, wherein a groove separating the ink ejection port array is formed between the ejection port arrays, and the depth of the groove is deeper than the ink ejection port and the ink flow path. 2. The ink jet recording head according to claim 1, wherein a flexible wiring substrate having connection pads for making electrical contact with the carriage is connected to the substrate, and the wiring substrate is fixed to the top plate. 3. An ink jet recording head, wherein the top plate according to claim 1 is a resin molded integrally. 4. The ink jet recording head according to claim 1, wherein a metal plate is provided on the elastic member side of the substrate. 5. The ink jet recording head according to claim 2, wherein a metal plate is provided on the elastic member side of the substrate, and the wiring substrate is fixed to the top plate and the metal plate. 6. An ink jet recording head according to claim 1, wherein the ink ejection direction is the same in each ink ejection port array with an error within ± 2 °. Recording head. 7. An ink jet recording head for discharging the ink according to claim 1, wherein:
An electrical connection surface is arranged within ± 5 ° in a direction perpendicular to the ink ejection direction of the head, and the ink ejection surface is arranged to project at least 5 mm toward the recording material side with respect to the electrical connection surface. An ink jet recording head characterized by the following. 8. The ink jet recording head according to claim 7, wherein the ink discharge unit is located at a distance of 2 with respect to the main scanning direction.
The first row of ink discharge units and their corresponding electrical connection surfaces are arranged in rows, and the second row of ink discharge units and their corresponding electrical connection surfaces are rotated 180 degrees around the center point of the second row. An ink jet recording head which is arranged at a rotated position. 9. The groove has a depth of 0.3 mm or more and a width of 0.5 mm.
2. The ink jet recording head according to claim 1, wherein the diameter is not less than mm. 10. The ink jet recording head according to claim 1, wherein ribs are provided in the vicinity of both ends of said groove in a direction perpendicular to an ink discharge port array. 11. An ink jet recording head according to claim 3, wherein a wedge member is provided near the center of said groove. 12. The ink jet recording head according to claim 11, wherein the wedge member is formed of the same material as a material forming the top plate. 13. An ink jet recording head according to claim 1, further comprising: a cleaning member for cleaning a discharge port surface of the top plate of the recording head where the ink discharge ports are provided. An ink jet recording apparatus characterized in that: 14. The ink jet recording apparatus according to claim 13, wherein the cleaning member is caused to enter the groove of the top plate when the cleaning member cleans the discharge port surface. 15. The printing apparatus according to claim 1, wherein the direction of movement of the cleaning member is different for each row of ink ejection ports of the recording head.
5. The ink jet recording apparatus according to 4.