JP2002011868A - Ink jet recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet recording apparatus in which a durability of a flexible substrate is high, enabling a carriage to be maintained to operate stably and enabling the apparatus to be made compact. SOLUTION: The carriage 2 movable in a horizontal scanning direction is arranged above a transfer face of a recording paper. Sub ink tanks 7, 8, 9 and 10 and a printing head are loaded to the carriage 2. There are set main ink tanks 3, 4, 5 and 6 for supplying ink via supply tubes 11a, 11b, 11c and 11d to the sub ink tanks 7-10. Furthermore, there are provided flexible substrate 13a and 13b for electrifying the printing head. The flexible substrates 13 and 13b are kept within a height of the sub ink tanks 7-10, made conductive to the printing head and developed in a space continuous with the lateral side of the sub ink tanks 7-10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus for printing by discharging ink from an ink jet provided on a carriage which moves in a main scanning direction orthogonal to a recording sheet fed.

[0002]

2. Description of the Related Art An ink jet recording apparatus is provided with a print head provided with a nozzle for discharging ink by an actuator such as a piezoelectric element on a carriage which reciprocates in a main scanning direction orthogonal to a paper feeding direction of the recording paper. The basic configuration is that ink is supplied to the printer.
The ink is stored in a main ink tank that is separate from the carriage, and a flexible supply tube that deforms from the main ink tank to a sub-ink tank mounted on the carriage following the movement of the carriage. A flow path is connected so that ink can be supplied from the main ink tank to the print head via the sub ink tank. In the case of color printing, inks of four colors of black, yellow, magenta, and cyan are used, and the main ink tank has a configuration in which these four kinds of ink are separated and stored, and a sub ink tank and a supply tube are provided. Are also arranged four each.

On the other hand, an actuator such as a piezoelectric element for pressurizing and discharging ink is incorporated in the print head, and a flexible substrate is electrically connected to the print head in order to energize the actuator such as the piezoelectric element from the power supply side. Connected. This flexible substrate is deformed following the movement of the carriage similarly to the supply tube. In a normal case, one or a plurality of flexible substrates are connected to the print head.

[0004]

However, in most of the conventional ink jet recording apparatuses, the flexible substrate from the power supply side to the print head is wired in such a manner as to rise up and bend. This is one of the reasons that since the positional relationship between the connection portion on the power supply side and the print head is shifted up and down, the flexible substrate must be wired so as to be drawn up and down.

On the other hand, the carriage on which the print head is mounted moves at high speed in the main scanning direction, and the flexible substrate is deformed with this movement. In this case, if the flexible substrate is wired so as to be drawn up and down, stress concentrates on the upper and lower bent portions, and the resistance of the bent portions acts on the movement of the carriage. For this reason, the mechanical strength of the flexible substrate at the portion where the stress is concentrated is deteriorated, the life is shortened, and the running speed of the carriage becomes unstable due to the resistance to the movement of the carriage, thereby deteriorating the print quality.

As described above, in the conventional ink jet recording apparatus, since the flexible substrate is drawn up and down, the durability of the flexible substrate is lowered and the operation of the carriage is unstable, and the vertical size of the flexible substrate is increased. Extra space is required for this.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an ink jet recording apparatus in which the durability of a flexible substrate is high, a stable operation of a carriage can be maintained, and the apparatus can be downsized.

[0008]

According to the present invention, a carriage movable in a main scanning direction is arranged above a recording paper conveying surface, and a sub ink tank and a print head are mounted on the carriage. An ink jet recording apparatus comprising: a main ink tank for supplying ink to the printhead via a supply means; and a flexible substrate for energizing the print head, wherein the flexible substrate is positioned within a height range of a sub-ink tank. The sub-ink tank is provided in a space connected to the side of the sub-ink tank.

In the present invention, since the flexible substrate is developed in a plane from the side of the sub-ink tank so as to be continuous with the sub-ink tank without being routed up and down, the bulk in the vertical direction can be reduced and the flexible substrate can be locally located. It is possible to improve the operability of the carriage without applying a specific stress.

[0010]

According to the first aspect of the present invention, a carriage movable in the main scanning direction is disposed above a recording paper conveyance surface, a sub ink tank and a print head are mounted on the carriage, and an ink tank is provided. An ink jet recording apparatus further comprising a flexible substrate for energizing the print head, wherein the flexible substrate is contained within the height range of the sub-ink tank and is electrically connected to the print head, and is provided on a side of the sub-ink tank. An ink jet recording apparatus which is provided by being developed in a continuous space, can reduce the vertical bulk, improve the durability of a flexible substrate, and improve the operability of a carriage. It has the action of:

According to a second aspect of the present invention, there is provided a supply means for supplying ink from the main ink tank to the sub ink tank, and the supply means is accommodated within the height of the sub ink tank and connected to the side of the sub ink tank. 2. The ink jet recording apparatus according to claim 1, wherein said ink jet recording apparatus is developed in a space, and has an effect that the height of an ink supply means such as a tube can be reduced.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing an essential part of an ink jet recording apparatus according to the present invention, FIG. 2 is a plan view of the same, and FIGS. 3 and 4 are views taken along lines AA and BB of FIG. FIG.

Referring to FIG. 1, the ink jet recording apparatus includes a frame 1 having a posture orthogonal to a recording paper conveying direction indicated by a dashed line, and a carriage 2 is mounted on a guide shaft 1a incorporated in the frame 1 for the recording paper. It is mounted movably in the direction perpendicular to the transport direction. The carriage 2 is connected to an endless belt (neither is shown) that runs by a carriage drive motor provided on the frame 1, and moves in the left-right direction in FIG. The driving of the carriage 2 by the carriage driving motor and the belt is conventionally known.

The recording paper P fed to the ink jet recording apparatus is conveyed by a paper feed roller 1b incorporated in the frame 1 and driven to rotate as shown in FIGS. 3 and 4, and a guide disposed downstream thereof. The sheet is fed at a constant speed while being guided by the block 1c and the guide roller 1d.

Main ink tanks 3, 4, 5, and 6, which store black, yellow, magenta, and cyan inks, respectively, are integrally fixed to the entrance side of the recording paper P of the frame 1. On the other hand, the carriage 2 has sub ink tanks 7, 8, 9, and 10 in which flow paths are connected to these main ink tanks 3 to 6, respectively.

3 and 4, the main ink tank 5 has a flat rectangular cross-sectional shape, and a needle 5a, which is a connecting means for connecting a flow path, is inserted into the inside thereof as an ink outlet. A flexible supply tube 11c, which is a supply means, is connected to 5a. The needle 5a is like an injection needle having a hollow inside, and sends out the ink in the main ink tank 5 to the supply tube 11c. Other main ink tank 3,
The tubes 4 and 6 have exactly the same structure, and supply tubes 11a, 11b and 11d are connected to the respective needles.

As shown in FIG. 3, a print head 12 for discharging ink by a piezoelectric element is connected to the lower surface of the sub ink tank 9. The print head 12 has a flow path connected to the sub-ink tank 9 and a nozzle disposed at the lower end thereof. As is conventionally known, ink is sucked from the main ink tank 5 by a capillary phenomenon caused by minute discharge holes provided in the nozzle. Then, an ink droplet is ejected from the ejection hole of the nozzle by applying a voltage to the piezoelectric element. Similar print heads are mounted on the other sub-ink tanks 7, 8, and 10. Then, in order to energize the print heads 12 and the print heads mounted on the sub-ink tanks 7, 8, and 10, respectively, the flexible substrates 13a and 13b which are electrically connected to a circuit board (not shown) arranged on the frame 1 side are printed. Connected to the head.

The supply tubes 11a to 11d are arranged in the vertical direction as shown in FIG. 4, and are arranged within the range of the height of the sub-ink tanks 7 to 10 (in the present embodiment, the print head is arranged from the upper surface of the highest sub-ink tank). 12 to the lower end of the passage for supplying ink to the ink supply passage 12). The supply tubes 11a to 11d from the main ink tanks 3 to 6 to the sub ink tanks 7 to 10 are all arranged in a horizontal posture. Therefore, the supply tubes 11a to 1a
Since 1d does not have a vertical drop over its entire length, no air bubbles are generated in the internal flow path, and the supply tubes 11a to 11d can be shortened and the pipeline resistance can be reduced as compared with a pipe that is drawn up and down.

On the other hand, the flexible substrates 13a and 13b are arranged so as to sandwich four supply tubes 11a to 11d arranged in the vertical direction, and are arranged so as to be spaced from each other. By providing a space between the flexible substrates 13a and 13b so as not to approach or contact each other, the flexible substrates 13a and 13b
The change of the mutual capacitance can be suppressed to optimize the voltage application to the piezoelectric element. Further, since both of the flexible substrates 13a and 13b can be brought into contact with the supply tubes 11a to 11d, the flexible substrate 13
a, 13b can also be suppressed from overheating.

The flexible substrates 13a and 13b are shown in FIG.
As is clear from FIG. 4 and FIG.
0 has the same width as the height of the sub ink tanks 7-1.
It is formed to draw a U-shape in a substantially horizontal plane so as to continue in the arrangement direction of 0s. That is, the flexible boards 13a and 13b are included in the horizontal plane without being routed in the up-down direction, and have no head and no bent portions in the up-down direction. Therefore, even if the flexible substrates 13a and 13b are deformed when the carriage 2 moves at high speed, stress is not locally concentrated on the flexible substrates 13a and 13b, and the resistance applied to the movement of the carriage 2 is reduced. Although the sub-ink tanks 7 to 10 are arranged in the scanning direction of the carriage 2 here, the sub-ink tanks may be in a direction perpendicular to the horizontal plane. Further, the sub ink tanks 7 to 10 do not have to be at the same height. In that case, the flexible substrates 13a and 13b need only be at the same height or lower than the highest sub-ink tank.

As is apparent from FIG. 3, the main ink tank 5 is arranged at a level included in the range in the height direction of the sub ink tank 9 and the print head 12 mounted on the carriage 2. And the main ink tank 5
The needle 5a for supplying ink from the sub ink tank 9 is included in the range in the height direction of the sub ink tank 9. Therefore, the level difference between the ink in the main ink tank 5 and the discharge end of the nozzle of the print head 12 is smaller than when the main ink tank 5 is arranged at a higher or lower level than the sub ink tank 9. And the head difference can be kept small. Such a configuration is equivalent to the other main ink tanks 3, 4, 6 and the sub ink tanks 7, 8, 10.
The same is true for the combination of. In the present embodiment, the supply tubes 1 from the main ink tanks 3 to 6 are provided.
Although a needle was used as a connecting member to 1a to 11d,
Other well-known ones may be used.

In the above configuration, when the recording paper P is fed at a constant speed in the direction indicated by the dashed line in FIG. 2 by the feed roller 1b, the carriage 2 moves in the left-right direction along the guide shaft 1a. That is, the carriage 2 moves in the main scanning direction, the recording paper P moves in the sub-scanning direction orthogonal to the main scanning direction, and ink is ejected by application of a voltage to the piezoelectric element of the print head in response to a print signal from the control unit, so that the recording paper P is discharged. Printed on P.

As shown in FIG. 3, the main ink tank 5 is included in the range of the height of the sub ink tank 9 mounted on the carriage 2, and the head difference between these tanks 5 and 9 is reduced. I have. Therefore, the main ink tank 5
The change in the water head pressure acting on the print head 12 becomes small irrespective of the size of the ink inside the print head 12, the discharge of the ink from the print head 12 is optimized, and the print quality on the recording paper P can be maintained high.

Further, since the main ink tanks 3 to 6 are included in the arrangement level of the sub ink tanks 7 to 10, the supply tubes 11a to 11d can be formed as substantially horizontal pipes without bending up and down. it can. For this reason, the supply tubes 11a to 11d can be shortened, so that the pipeline resistance to the sub ink tanks 7 to 10 can be reduced, and the ink can be stably supplied. And supply tubes 11a to 11d
Is maintained in a substantially horizontal position, so that air bubbles do not accumulate in the flow path, and high printing quality can be obtained.

The flexible substrates 13a and 13b
Are formed so as to form a U-shape in a substantially horizontal plane so as to continue in the arrangement direction of the sub-ink tanks 7 to 10 as described above. For this reason, the bulk in the vertical direction is reduced and the device can be downsized.
Since a and 13b are also shorter than in the conventional structure, power consumption is reduced and unnecessary radiation is eliminated. In addition, since the local stress generated in the flexible substrates 13a and 13b is reduced, the durability of the flexible substrates 13a and 13b is also improved. Since the flexible substrates 13a and 13b are quickly deformed, the resistance to the movement of the carriage 2 is reduced, the operability of the carriage 2 is improved, and good printing is maintained.

As can be seen from FIG. 1, the width of the flexible substrates 13a and 13b in the vertical direction (the direction substantially perpendicular to the horizontal plane) is adjusted so that the supply tubes 11a to 11d do not protrude. Is formed wider than the lower end than the upper end. With such a configuration, the supply tubes 11a to 11d having a large resistance at the time of contact are provided.
Is suppressed from coming into contact with other members, so that the operation of the carriage 2 is stabilized and the print quality is improved.

Further, in the present embodiment, the number of colors of ink is four, but may be more. In that case, the number of supply tubes and ink tanks may be increased according to the number of colors.

[0029]

According to the present invention, since the flexible substrate is contained within the height range of the sub-ink tank and is developed in a plane connected to the side of the sub-ink tank, the bulk in the vertical direction is reduced, and Can be reduced in size. In addition, since no local stress is generated on the flexible substrate, the durability of the flexible substrate is improved, and the operability of the carriage is also increased, thereby maintaining a good printing operation.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a main part of an ink jet recording apparatus of the present invention.

FIG. 2 is a plan view showing a main part of the ink jet recording apparatus of the present invention.

FIG. 3 is a longitudinal sectional view taken along line AA of FIG. 2;

FIG. 4 is a longitudinal sectional view taken along line BB of FIG. 2;

[Explanation of symbols]

 1 Frame 1a Guide shaft 1b Paper feed roller 1c Guide block 1d Guide roller 2 Carriage 3, 4, 5, 6 Main ink tank 5a Needle 7, 8, 9, 10 Sub ink tank 11a, 11b, 11c, 11d Supply tube 12 Printing Heads 13a, 13b Flexible board P Recording paper

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yutaka Miyazono 1006 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Tetsuya Matsuzaki 1006 Kadoma Kadoma Kadoma City, Osaka Matsushita Electric Industrial F Terms (reference) 2C056 EA21 EA23 FA04 HA38 HA52 KB15 KB37 KC02

Claims (2)

[Claims] A carriage movable in a main scanning direction is disposed above a recording paper conveying surface, a sub-ink tank and a print head are mounted on the carriage, and ink is supplied to the sub-ink tank via supply means. An ink jet recording apparatus comprising: a main ink tank to be supplied; and a flexible substrate for energizing the print head, wherein the flexible substrate is contained within a height range of a sub-ink tank and is electrically connected to the print head. And an ink jet recording apparatus, wherein the ink jet recording apparatus is provided in a space connected to the side of the sub ink tank. And a supply means for supplying ink from the main ink tank to the sub ink tank, wherein the supply means is accommodated within the height of the sub ink tank and is connected to a side of the sub ink tank. The ink jet recording apparatus according to claim 1, wherein the ink jet recording apparatus is developed.