JPH0647920A - Nozzle head maintenance device in ink jet printer - Google Patents

Abstract

PURPOSE:To reduce a sweeping stroke of suction ports by a factor of the number of the suction ports to obtain a small maintenance device and smoothly conduct the parallel displacement of the suction ports by a method wherein the two suction ports are spaced from each other by a distance obtained by dividing a length of an orifice array by the number of the suction ports. CONSTITUTION:A vertical shaft 21 and the tip ends of suction ports 19 are disposed in proximity to each other with respect to the crosswise direction of a printer body. A distance (d) is approximately one-half of a length of an array of orifices 4. The two suction ports 19 are so disposed as to abut on an orifice plate 5 at the orifices 4. In this manner, by rotating a drive lever 11 in a direction of an arrow C, the two suction ports 19 sweep the orifices 4 from end to end. A bubble in a pressure chamber of a nozzle head is swept through each of the orifices 4. In this manner, the stroke of the drive lever 11 is slightly smaller than one-half of a width (b) of the orifice plate 5.

Description

Detailed Description of the Invention

The present invention relates to a maintenance device for a nozzle head of an inkjet printer.

[0002]

2. Description of the Related Art In an ink jet printer, a carriage having a nozzle head is moved to a nozzle head maintenance position while printing is stopped, and the nozzle head is usually capped to prevent the ink of the printing nozzles from drying. At the same time, the bubbles generated in the ink in the pressure chamber of the nozzle head are removed by suction by the pump.

A conventional technique will be described below with reference to FIG.

The carriage 1 is slidably mounted on a slide shaft 3 which extends the printer main body 2 left and right. An orifice plate 5 in which ink ejection orifices 4 are arranged is attached to the head side of the carriage 1. The arrangement of the orifices 4 in the orifice plate 5 is shown in FIG. Forty-eight orifices 4 are arranged in a line obliquely to the horizontal.

A nozzle head maintenance section 5 is provided on one side of the printer body 2. The maintenance section 5 is provided with a slide shaft 7 which extends along the orifice 4 and extends left and right, and a slide guide 9 having one suction port 8 is mounted on the slider shaft 7 so as to be slidable left and right. Has been done. The slide guide 8 is provided with a slide 10 in the front-back direction of the printer body 2, and the slider 10 is engaged with a pin 12 provided at the tip of a drive lever 11 which is rotatable around a vertical shaft 20. ing. As a result, when the drive lever 11 rotates in the direction of arrow A, the suction port 8 sweeps the orifices 4 from end to end (FIG. 3), and sucks bubbles in the pressure chamber of the nozzle head from each orifice 4.

[0006]

The width b of the conventional nozzle head maintenance device is set to be approximately the same as the width bc of the carriage 1 in order to avoid the enlargement of the device (FIG. 1). Therefore, the width bg of the slide guide 9 that supports the suction port 8 and slides to the left and right is also small, which makes smooth parallel movement difficult. As a result, it becomes difficult to maintain airtightness between the suction port 8 and the orifice plate 5. Since the drive lever 11 that drives the slide guide 9 also needs a large stroke corresponding to the width b, it is difficult to design the drive lever 11 and the like.

It is an object of the present invention to provide a nozzle head maintenance device for an ink jet printer which can reduce the sweep stroke of the suction port with respect to the orifice plate of the nozzle head.

[0008]

According to the present invention, an orifice plate provided on a nozzle head of a carriage and having a plurality of orifices arranged in a slanting row, and a part of the orifices for sucking the orifices. And a suction port configured to sweep along a row of orifices, the suction ports being spaced apart by a length of the row of orifices divided by the number of suction ports, respectively. It is achieved by a nozzle head maintenance device of an inkjet printer.

[0009]

According to the present invention, at least two suction ports are
Since the lengths of the rows of orifices are separated by the value obtained by dividing the length by the number of suction ports, the sweep stroke of the suction port can be reduced to the value obtained by dividing the stroke by the number of suction ports, resulting in downsizing of the maintenance device. At the same time, the parallel movement of the suction port can be performed smoothly.

The number of suction ports according to the device of the present invention may be two or three or more.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the preferred embodiments shown in FIGS. The same components as those in FIG. 1 are designated by the same reference numerals.

The carriage 1 is slidably mounted on a slide shaft 3 extending leftward and rightward (direction B) of the printer body 2. The platen 30 is driven by a paper feed motor 31.

An orifice plate 5 in which ink ejection orifices 4 are arranged is attached to the head side of the carriage 1. The arrangement of the orifices 4 in the orifice plate 5 is shown in FIG. Forty-eight orifices 4 are arranged in a line obliquely to the horizontal.

The carriage 1 moves in the B direction during printing,
It is configured to return to one side portion (home position) of the printer body 2 while printing is stopped. The nozzle head maintenance unit 6 is provided at the home position.

The maintenance section 6 is provided with a slide shaft 7 which is inclined along the orifice 4 and extends left and right, and a slide guide 18 is mounted on the slide shaft 7 so as to be slidable left and right. A slider 10 is provided on the slide guide 18 in the front-back direction of the printer body 2, and the slider 10 includes a pin 12 provided at the tip of a drive lever 11 that is rotatable around a vertical shaft 20. ing. Two suction ports 19 separated from each other by a distance d are attached to the slide guide 18 so as to be rotatable around a vertical shaft 21. The vertical shaft 21 and the tip of the suction port 19 are close to each other in the front-back direction of the printer body 2. Here, the distance d is approximately 1 / the length of the row of orifices 4.
It is 2. The two suction ports 19 are arranged in the orifice 4 so as to abut the orifice plate 5.
As a result, when the drive lever 11 rotates in the direction of arrow C, the two suction ports 19 sweep the orifices 4 from one end to the other (FIG. 7), and the bubbles in the pressure chamber of the nozzle head are discharged from each orifice 4. Suction. As a result, the stroke of the drive lever 11 is 1 / the width b of the orifice plate 5.
It becomes a little less than 2.

In this embodiment, the slider 18 is connected to the drive lever 11 by the slider / flank mechanism, but may be formed by a flexible member.

The structure of the pressure chamber of the nozzle head will be described below with reference to FIG.

A pressure chamber 42 is formed in a cavity inside the nozzle head 41. The pressure chamber 42 is opened by the nozzle 43. The nozzle head 41 is fixed to the base 44. The base 44 is provided with an opening communicating with the pressure chamber 42, and a filter 45 made of non-woven fabric is inserted into the opening.

An ink tank 50 is attached to the base 44, and an opening of the ink tank 46 is connected to an opening into which the filter 45 is inserted.

The nozzle head 41 is provided with a prismatic hole 46 communicating with the pressure chamber 42 from below.
A prismatic piezo element 47 is inserted in the inside. When a current flows through the piezo element, the piezo element expands by about 1 micron to pressurize the ink in the pressure chamber 42 and eject the ink from the nozzle 43.

The tip of the piezo element is covered with a ceramic cap 48, and further the silicon cap 4
9 is covered.

The mechanistic analysis of the embodiment of the present invention will be described below with reference to FIG. The same components as those in FIGS. 4 to 7 are designated by the same reference numerals.

In order to maintain airtightness between the suction port 19 and the orifice plate 5, a force P is applied to the suction port 19 toward the orifice plate 5. Suction port 1
Since there are two 9, the force of P / 2 is applied to each suction port 19.

When the slide guide 18 is moved to the right, a force F is generated by the frictional resistance between the suction port 19 and the orifice plate 5. This force F causes a rotational moment T of F × l. Here, 1 is the distance between the vertical shaft 2 and the tip of the suction port 19.

Therefore, at the suction port 19 on the right side, the pressing force P /
2, the pressing force F × l / d due to the torque T is applied to the suction port 19 on the left side from the pressing force P / 2 to the force F due to the torque T.
X1 / d is reduced. This torque T is T = when l = 0
It becomes 0. In that case, the pressing forces of the left and right suction ports 19 on the orifice plate 5 become equal.

On the other hand, according to the structure of the embodiment shown in FIG. 4, it is possible to reduce the difference in pressing force between the left and right suction ports 19 against the orifice plate 5.

[0027]

According to the present invention, since at least two suction ports are separated from each other by a value obtained by dividing the length of the row of orifices by the number of suction ports, the stroke of sweeping the suction ports is changed to the suction port. The maintenance device can be downsized, and the suction port can be smoothly moved in parallel.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a conventional nozzle head maintenance device.

FIG. 2 is a diagram showing an array of orifices in an orifice plate.

FIG. 3 is a diagram for explaining how a conventional suction port is swept.

FIG. 4 is a schematic diagram illustrating the overall arrangement of the printer.

FIG. 5 is an explanatory diagram of an example of the present invention.

FIG. 6 is a diagram showing an array of orifices of an orifice plate.

FIG. 7 is a diagram for explaining how the suction port is swept according to the device of the present invention.

FIG. 8 is a diagram illustrating a structure of a pressure chamber of a nozzle head.

FIG. 9 illustrates a mechanistic analysis of an example of the present invention.

[Explanation of symbols]

 1 Carriage 2 Printer Main Body 3,7 Slide Shaft 4 Orifice 5 Orifice Plate 6 Nozzle Head Maintenance Section 11 Drive Lever 18 Slide Guide 19 Suction Port

Claims (1)

[Claims] 1. An orifice plate provided in a nozzle head of a carriage, wherein a plurality of orifices are obliquely arranged in a row, and an orifice plate that abuts a part of the orifices for sucking the orifices and is arranged in the row of the orifices. At least two of the suction ports configured to sweep along, wherein the suction ports are each separated by a length of a row of the orifices divided by the number of the suction ports. A nozzle head maintenance device for inkjet printers.