JPH10286973A - Recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a recorder capable of preventing a meniscus of a nozzle from going back even when a head face of the recording head is covered with a cap and bubbles from entering an inner section of the nozzle, and of making it easy to eject ink in the next printing. SOLUTION: Air holes 11a, 11b each having an end at a head face 1a are provided recording head 1. There are provided stopping valves 13a, 13b each of which is opened and closed in order to maintain a pressure in a cap 16 made of an elastic material to be roughly equal to that of the open air in the case where the head face 1a of the recording head 1 is covered with the cap 16 when the recording head mounted on a carriage 2 which is moved to a head standby position along a carriage shaft 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording head used in an ink jet printer or the like for recording by discharging ink onto a recording medium.

[0002]

2. Description of the Related Art Conventionally, a recording apparatus, such as an ink jet printer, which discharges ink onto a recording medium to perform recording,
At the time of printing standby, the carriage on which the recording head is mounted is moved along the carriage shaft to the head standby position, and a cap made of an elastic material is put on the head surface of the recording head,
Dust, foreign matter, air, and the like in the nozzles are sucked from the nozzles that eject the ink, and the nozzles are on standby.

[0003]

In the conventional recording apparatus, when the cap is put on the head surface of the recording head, the pressure in the cap increases, so that the meniscus of the nozzle recedes, and furthermore, the air bubbles are generated in the nozzle. And there is a problem that ink ejection failure occurs at the next printing.

According to the present invention, a recording apparatus which, even when a cap is put on the head surface of a recording head, does not cause the meniscus of the nozzle to recede, does not contain bubbles in the nozzle, and satisfactorily discharges ink at the next printing. It is intended to provide.

[0005]

In order to achieve the above object, in a recording apparatus according to the present invention, a vent hole having one end is provided on a head surface of a recording head. Is kept almost at atmospheric pressure.

[0006]

Embodiments of the present invention will be described with reference to the drawings. Elements common to the drawings are denoted by the same reference numerals. First Embodiment FIG. 1 is A-A sectional view on arrows of a printing apparatus shown in FIG. 2, FIG. 2
FIG. 1 is a schematic diagram illustrating a configuration of a main part of a recording apparatus according to a first embodiment. As shown in FIG. 2, the recording head 1 is mounted on a carriage 2 and has an arrow B- along a carriage shaft 5 whose both ends are supported by side frames 3, 4 (side frames 4 are not shown). It is provided movably in the C direction.

As shown in FIG. 1, the recording head 1 includes an ink tank 7 containing ink with a main body 6 fixed to the carriage 2 interposed therebetween, and a nozzle plate 8 for discharging ink to a print medium. It is provided. The nozzle plate 8 is provided with a discharge nozzle 9 having a small diameter.
Is provided with an ink flow path 10 connecting the discharge nozzle 9 and the ink chamber 7a of the ink tank 7. Therefore, the discharge nozzle 9 has one end communicating with the ink chamber 7a of the ink tank 7 and the other end on the head surface 1a.

Further, ventilation holes 11a and 11b having one end are provided in the head surface 1a of the recording head 1, and the ventilation holes 11a and 11b are provided.
a, a support shaft 1 provided on the main body 3
Sealing valves 13a and 13b are attached to 2a and 12b so as to be rotatable in the directions of arrows FG and HI.

As shown in FIG. 2, the side frames 3 and 4 are erected on a housing having a platen 14 and a waste ink storage unit 15. There is a head standby position above the waste ink storage unit 15, and the recording head 1 which stands by at the head standby position
The cap 16 which covers the head surface 1a is connected to the waste ink storage unit 15 via a pipe 17. When the recording head 1 moves to the head standby position, the head surface 1
The wiper plate 18 contacting the a is connected to the waste ink storage unit 15 via the pipe 19.

The cap 16 is made of an elastic material, and is provided so as to be movable in the direction of the arrow DE by using the driving force of a line feed motor (not shown). As shown in FIG. 1, the cap 16 presses and covers the edge 16 a against the head surface 1 a of the recording head 1.
A pump 20 for sucking foreign matter, air, and the like is provided in the middle of the pipe 17.

FIGS. 3A to 3C are explanatory views showing the state of the head according to the first embodiment at the time of head standby. FIGS.
This shows a state where the cap operation is stopped. Note that only the ink is hatched for easy viewing.

Next, the operation will be described. At the time of head standby, as shown in FIG. 2, the carriage 2 is moved in the direction of arrow C to stop at the head standby position outside the print area. Next, as shown in FIG. 3A, the cap 16 is moved in the direction of arrow D.

Until the edge 16a of the cap 16 contacts the head surface 1a of the recording head 1, the atmospheric pressure acts on the meniscus 21 in the discharge nozzle. The edge 16a of the cap 16 abuts on the head surface 1a of the recording head 1, and moves the cap 16 in the direction of arrow D to further improve the sealing performance.

When the pressure inside the cap becomes higher than the atmospheric pressure, as shown in FIG.
Bulges outward to reduce the volume inside the cap, and the pressure inside the cap becomes higher than the atmospheric pressure.

When the pressure in the cap becomes higher than the atmospheric pressure, the sealing valves 13a and 13b rotate in the directions of arrows F and H,
The air in the cap escapes through the ventilation holes 11a and 11b as shown by arrows, and acts to maintain the pressure in the cap at approximately atmospheric pressure. Therefore, the meniscus in the discharge nozzle does not recede, and further, does not include bubbles in the nozzle.

When the cap 16 stops moving and the pressure in the cap returns to the atmospheric pressure, the sealing valves 13a and 13b rotate in the directions of arrows G and I to close the ventilation holes 11a and 11b, and the inside of the cap is closed. Sealed.

According to the first embodiment, since the recording head is provided with the vent hole and the sealing valve, the pressure in the cap can be maintained at substantially the atmospheric pressure even when the cap is pressed against the head surface. The meniscus inside does not recede and does not contain bubbles in the nozzles, so that the ink is favorably ejected at the next printing.

Second Embodiment FIG. 4 is a sectional view showing a main part of a recording apparatus according to a second embodiment . The difference from the recording apparatus according to the first embodiment is that a sealing valve 13a is provided. , 13b are removed, and a notch 22b is provided on the edge 22a of the cap 22 along the inner periphery of the edge 22a so as to cause buckling when the pressing force of the cap 22 reaches a predetermined value. Has a cap 2
The second edge 22a covers one end of the ventilation holes 11a and 11b.

FIGS. 5A to 5C are explanatory diagrams showing the state of the head according to the second embodiment at the time of head standby. FIGS.
This shows a state where the cap operation is stopped. Note that only the ink is hatched for easy viewing.

Next, the operation will be described. At the time of head standby, as shown in FIG. 2, the carriage 2 is moved in the direction of arrow C to stop at the head standby position outside the print area. Next, as shown in FIG. 5A, the cap 22 is moved in the direction of arrow D.

Until the edge 22a of the cap 22 contacts the head surface 1a of the recording head 1, the atmospheric pressure acts on the meniscus 21 in the discharge nozzle. When the edge 22a of the cap 22 contacts the head surface 1a of the recording head 1 as shown in FIG. 5B, the pressure in the cap becomes higher than the atmospheric pressure.

When the pressure in the cap becomes higher than the atmospheric pressure, the air in the cap escapes through the ventilation holes 11a and 11b as shown by arrows, and acts to maintain the pressure in the cap at atmospheric pressure. Therefore, the meniscus in the discharge nozzle does not recede, and further, does not include bubbles in the nozzle.

When the cap 22 is further moved in the direction of arrow D, the edge 22a of the cap 22 buckles at the notch 22b, and the tip of the edge 22a closes the ventilation holes 11a and 11b. At this position, the cap 22 stops moving. Therefore, while the pressure in the cap is maintained almost at atmospheric pressure,
The inside of the cap is sealed.

According to the second embodiment, since a sealing valve or the like is not required, the configuration is simpler than that of the first embodiment.

Third Embodiment FIG. 6 is a schematic view showing a main structure of a recording apparatus according to a third embodiment, and FIG. 7 is a sectional view of the recording apparatus shown in FIG. . The difference from the recording apparatus according to the first embodiment is that, as shown in FIG. 6, instead of the sealing valves 13a and 13b, sealing plates 23a and 23b are provided to be inclined in side frames, and a carriage shaft is provided. 5 is a side frame
A knock pin 5a press-fitted into the carriage shaft 5 comes into contact with a protrusion 3a provided on the side frame 3 so that the head surface 1 of the recording head 1 can be rotated.
A predetermined distance is provided between a and the platen 14.

When the cap 16 reaches a predetermined position, the sealing valves 13a and 13b allow the air holes 11a and
11b is closed at one end.

FIGS. 8A and 8B are explanatory views showing the state of the head according to the third embodiment at the time of standby, and FIGS. 8A and 8B show the state when the cap abuts and the cap operation is stopped, respectively.

Next, the operation will be described. At the time of head standby, as shown in FIG. 6, the carriage 2 is moved in the direction of arrow C to stop at the head standby position outside the print area. Next, the cap 16 is moved in the direction of arrow D.

Until the edge 16a of the cap 16 contacts the head surface 1a of the recording head 1, the atmospheric pressure acts on the meniscus 21 in the discharge nozzle as described in the first embodiment. The edge 16a of the cap 16 is
As shown in FIG. 2A, when the recording head 1 comes into contact with the head surface 1a, the pressure in the cap becomes higher than the atmospheric pressure.

When the pressure in the cap becomes higher than the atmospheric pressure, the air in the cap escapes through the ventilation holes 11a and 11b as shown by arrows, and acts to maintain the pressure in the cap at substantially the atmospheric pressure. Therefore, the meniscus in the discharge nozzle does not recede, and further, does not include bubbles in the nozzle.

Further, when the cap 16 is moved in the direction of arrow D, as shown in FIG.
Buckling, and the tip of the edge 16a is
Close b. At this position, the cap 16 stops moving.
Therefore, while the pressure inside the cap is maintained at atmospheric pressure,
The inside of the cap is sealed.

According to the third embodiment, the recording head is fixed by being sandwiched between the cap and the sealing plate.
Ensure capping action

[0033]

Since the present invention is configured as described above, it has the following effects. By providing a vent hole having one end on the head surface of the recording head, and by covering the head surface with a cap, by keeping the inside of the cap at substantially atmospheric pressure, the meniscus of the nozzle is not retracted,
Further, no ink is contained in the nozzle, and the ink is favorably ejected at the next printing.

[Brief description of the drawings]

FIG. 1 is a sectional view of the recording apparatus shown in FIG.

FIG. 2 is a schematic diagram illustrating a main configuration of the recording apparatus according to the first embodiment.

FIG. 3 is an explanatory diagram illustrating a state at the time of head standby according to the first embodiment;

FIG. 4 is a cross-sectional view illustrating a main configuration of a recording apparatus according to a second embodiment.

FIG. 5 is an explanatory diagram showing a state at the time of head standby according to a second embodiment.

FIG. 6 is a schematic diagram illustrating a main configuration of a recording apparatus according to a third embodiment.

7 is a cross-sectional view of the recording apparatus shown in FIG. 6 taken along the line AA.

FIG. 8 is an explanatory diagram illustrating a state during head standby according to a third embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Recording head 11a, 11b Vent hole 13a, 13b Sealing valve 16, 22 Cap 23a, 23b Sealing plate

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Noboru Oishi 4-11-11 Shibaura, Minato-ku, Tokyo Inside Oki Data Corporation

Claims (4)

[Claims] A carriage on which a recording head is mounted is moved along a carriage shaft to a head standby position;
In a printing apparatus in which a cap made of an elastic body is put on a head surface of a print head and dust, foreign matter, air, and the like in the nozzles are sucked from a nozzle for discharging ink, the print head has one end on the head surface. A recording apparatus, wherein pores are provided, and when the cap is placed on the head surface, the inside of the cap is maintained at substantially atmospheric pressure. 2. The recording apparatus according to claim 1, wherein the ventilation hole has a sealing valve at the other end which opens when the air pressure in the cap becomes higher than the atmospheric pressure. 3. An edge of the cap is provided with a notch along an inner periphery of the edge so as to cause buckling when a pressing force of the cap reaches a predetermined value. 2. The recording apparatus according to claim 1, wherein an edge covers one end of the ventilation hole. 4. A seal, which is rotatably provided on a carriage shaft to a predetermined position, covers the head surface of the recording head, and closes the other end of the air hole when the carriage rotates to a predetermined position. The recording apparatus according to claim 1, further comprising a stop plate.