JPH10175293A - Ink-jet printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To rapidly and accurately execute relative positioning of a rotary member and a nozzle head. SOLUTION: The ink-jet printer is formed so that a printing medium is held on a rotatable rotary member (drum 10) and ink sent from a nozzle head 200 is formed as a jet so as to print a character and an image or the liek on the printing medium which is held on the rotary member 10 and rotated. Further, relative positioning in the direction Z1 of both the rotary member 10 and the nozzle head 200 is performed by allowing the nozzle head 200 (205) to indirectly abut against a position regulation member 105 regulating the position of the rotary member 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 printer in which a print medium is held by a rotatable rotating member, and ink jet printing is performed on a print medium being rotated so that characters and images can be printed.

[0002]

2. Description of the Related Art For example, a nozzle head for each color is reciprocated over the entire length in the row direction, and printing is performed during each forward movement.
Compared to a so-called serial type ink jet printer in which line printing is performed, and after one line printing, a printing medium (plain paper, OHP paper, etc.) M is fed one line in the column direction and these are repeated, printing speed can be greatly increased compared to a so-called serial type ink jet printer. The present applicant has proposed an ink jet printer capable of continuous printing operation over a large number of sheets and capable of achieving a significant reduction in size as compared with a so-called laser printer (for example, Japanese Patent Application No. 8-296959).
Have been.

In FIG. 4, a drum (rotating member) 10 is rotatable at a constant peripheral speed and can hold a print medium M on an outer peripheral surface 11 thereof. That is, the print medium M is held on the outer peripheral surface 11 of the drum 10 by using the holding force of the medium holding means, and is rotationally transferred by using the rotation of the drum 10. As the medium holding means, for example, a holding force is obtained by using a charge attracting force due to charging of the charging roller 21. However,
Negative pressure suction force and mechanical clamping force can be used together.

A nozzle head (print head) 200 for each color is arranged in the rotation (Y) direction of the drum 10. Therefore, the reciprocating movement means 30 can be used to reciprocate the integrated nozzle head 200 for each color over the entire length in the row direction (perpendicular to the paper surface) or the integrated nozzle head 200 for each color in which a plurality of nozzle head elements are arranged in the row direction. For example, ink is sprayed from the inkjet nozzles 207 for each color on the rotating printing medium M while continuously or intermittently reciprocating by the pitch between inkjet nozzles (for example, 1/75 inch), and printing is performed in the row direction. Printing in the column direction can be performed while utilizing the rotation of the drum 10 during the forward movement of the intermediate pitch. That is, since the line-direction printing and the column-direction printing can proceed simultaneously, the printing speed can be greatly increased.

Further, since the nozzle heads 200 for each color and the ink tanks (ink cassettes) 213 for the respective colors are arranged at separate positions, the nozzle heads 200 for the respective colors are provided.
In addition to the fact that the printing speed can be reduced and the reciprocating speed in the row direction can be greatly increased, the printing speed can be further increased, and the capacity of the ink tank (ink cassette) 213 for each color can be greatly increased. This allows continuous printing operation.

In order to realize these, around the drum 10, a heater 22 for drying the ink on the rotating print medium M, and a charge is replenished to stabilize the charge adsorption force attenuated by printing. A replenishing charging unit 24 and a charge removing unit 25 for eliminating the charge adsorbing force prior to peeling of the print medium M after printing are provided. Further, a medium feeding means 60 and a medium feeding means 90 are provided on one (right side in FIG. 4) side of the drum 10 and a medium peeling means on the other side (left side in FIG. 4) for continuous printing operation. 140, a medium discharging / conveying means 160 and a direction switching means 190 are provided.

The medium feeding means 60 includes a cassette feeding means 7.
The print medium M can be selectively fed one sheet at a time from either one of the manual feeding means 61 and the manual feeding means 61. Medium supply means 90
Supplies the fed print medium M to the drum 10 at a predetermined timing. The medium peeling means 140 peels the print medium M from the drum 10 after printing, and the medium discharge / transport means 160 discharges and transports the peeled print medium M leftward in FIG. The direction switching unit 190 selectively switches between the discharge tray 192 and the upper discharge tray 193.

Thus, the feeding, supply, holding, rotational transfer, printing, peeling, and discharging and conveying of the printing medium M can be continuously performed, so that multicolor printing of, for example, 20 sheets or more of A4 size in one minute can be performed. it can. Further, according to such a previously proposed ink jet printer, the higher the rotational speed of the drum 10 and the reciprocating movement speed of the nozzle head 200, the more drastically the printing speed can be increased. In addition, a printing operation in which the resolution is switched becomes possible.

[0009]

In the ink jet printer proposed above, the relative positioning accuracy between the outer peripheral surface 11 of the rotating member (10) and the nozzle head 200 is important. Therefore, the position of the rotating member (10) is regulated using the position regulating member, and the position of the nozzle head 200 is adjusted with respect to the rotating member (10). For example, the inkjet nozzle 207 and the outer peripheral surface 11 are positioned at 1 to 5 mm.

However, as the continuous recording time of the nozzle head 200 becomes longer, ink adheres to the discharge port thereof, resulting in deterioration of print quality. Therefore, maintenance including cleaning is required periodically.

Thus, the outer peripheral surface 11 and the nozzle head 20
Since the interval from 0 must be widened, repositioning between the two 11, 200 must be performed after maintenance, but it takes a lot of trouble and time. Further, longer maintenance time hinders higher recording speed.

An object of the present invention is to provide an ink jet printer which can quickly and accurately position a rotary member and a nozzle head.

[0013]

According to a first aspect of the present invention, a print medium is held on a rotatable rotating member, and ink is jetted from a nozzle head onto the printing medium held by the rotating member and rotating, to print characters and characters. Formed such that images and the like can be printed, and formed so that the relative positioning between the rotating member and the nozzle head can be performed by directly or indirectly contacting the nozzle head with a position regulating member that regulates the position of the rotating member, It is characterized by the following.

In this invention, in order to position the nozzle head relative to the rotating member after maintenance, the nozzle head may be brought into contact with a position regulating member for regulating the position of the rotating member. Therefore, relative positioning between the rotating member and the nozzle head can be performed quickly and accurately, and handling is very easy.

The invention according to a second aspect is an ink jet printer in which the rotating member and the nozzle head are formed so as to be movable respectively.

In this invention, since both the rotating member and the nozzle head can be moved individually, the same operation and effect as those of the first invention can be obtained. The amount of movement can be reduced, and the rotating member can be taken out of the main body case.

Further, the invention according to a third aspect is an ink jet printer wherein the rotary member and the nozzle head are formed so as to be relatively positioned in two orthogonal directions.

In this invention, since the rotary member and the nozzle head can be relatively positioned in two orthogonal directions,
In addition to providing the same effects as those of the first and second aspects of the present invention, it is easy to stabilize the printing accuracy in the column direction of the printing medium.

Still further, according to the present invention, the relative positioning between the rotary member and the nozzle head via the position regulating member utilizing a power source for moving the rotary member and / or the nozzle head. This is an inkjet printer formed so as to be able to maintain a state.

According to this invention, after the relative positioning between the rotary member and the nozzle head is performed by the power source, the relative positioning state can be maintained by using the power source. Therefore, the same operation and effect as those of the inventions according to the first to third aspects can be obtained, and the handling is further facilitated.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 and 2, the inkjet printer has a rotatable rotating member (drum 1).
0), the print medium M is held. The ink is jetted from the nozzle head 200 onto the rotating print medium M held by the rotating member (10) to form characters and images so as to be printable. The nozzle head 200 (205) is indirectly contacted with the position regulating member (105) for regulating the position of (10), so that the relative positioning between the rotating member (10) and the nozzle head 200 in the Z1 direction can be performed. Have been.

In this embodiment, the rotary member (drum 10) is also formed so as to be movable in the Z2 direction in FIG. This is for convenience such as jam processing.

Further, in this embodiment, a case will be described in which the basic configuration is constructed in the same manner as the case of the previously proposed ink jet printer (FIG. 4). The description of the same parts as those in FIG. 4 will be simplified or omitted.

In FIG. 1, a drum 10 has a frame 10
0, is rotatably held about an axis X0, and one of the supply rollers 91 of the medium supply means 90, one of the guides 95, while maintaining a predetermined relative position around the held drum 10.
The charging roller 21, the heater 22, the replenishing charging unit 24, and the charge removing unit 25 are mounted on the same frame 100.

The other supply roller 92 and the other guide 96 forming the medium supply means 90 are fixedly mounted on the main body case side.

The frames 100 are provided as a pair on the left and right (in the vertical direction on the paper surface of FIG. 1), and are movable in the Z2 direction along the guide rail 1 fixed to the main body case side. Therefore, since the drum 10 and the like can be taken out of the main body case as it is, jam processing and the like can be easily performed.

The drum position restricting means for restricting the drum 10 to a predetermined position in the main body case includes a position restricting pin 2 horizontally fixed to a bracket (not shown) in the main body case.
, A concave position restricting portion 101 provided below the frame 100, and a lever 103 with a hook 104 rotatable about a shaft 102 fixed to the frame 100. The hook 104 is urged in a direction in which the hook 104 is engaged with the position regulating pin 2 (omitted).

Accordingly, the hook 1 is released by releasing the urging force of the spring.
04, the frame 100 can be moved along the guide rail 1 in the Z2 direction. On the contrary, the frame 100 is pushed from outside the main body case so that the position restricting portion 101 abuts on the position restricting pin 2 and the hook 104 is pressed by the spring. Is engaged with the position regulating pin 2, the frame 100, that is, the drum 10 can be accurately regulated at a predetermined position in the main body case.

Here, the position restricting member is absolutely formed of the position restricting pins 2, but in this embodiment, relative to the nozzle head 200, relative to the position (layout), the position of the frame 100 is limited. The second position regulating pin 105 fixed horizontally is constructed so as to be usable as a substantial position regulating member. That is, the drum 1
The indirect position regulating pin (105) is introduced on the premise of the accurate positioning function of zero. Of course, the position regulating pins 2 and the frame 100 can be directly used as the position regulating member.

On the other hand, the nozzle head 200 is mounted on a reciprocating table 31 which can reciprocate in the drum axis direction (row direction), that is, in the direction perpendicular to the plane of FIG. 1 on slide guides 45, 45 mounted on the reciprocating table 41. Have been.
Further, the reciprocating table 31 is attached to the forward / backward moving table 41 via a connecting piece 35 so as not to be relatively displaceable in the Z1 (drum diameter) direction.

The reciprocating means 30 comprises the reciprocating table 31 and a link mechanism, a motor and the like (not shown) for reciprocating the table 31 in the row direction.

Next, the reciprocating means 40 comprises the reciprocating table 41 mounted on a guide rail (not shown) on the main body case side so as to be movable in the Z1 direction, and a rack 42 mounted on the lower surface of the table 41. , A pinion 43 that meshes with the rack 42, and a drive source 44 that rotates the pinion 43.

In this embodiment, the drive source 44 is formed of a DC servo motor or a stepping motor capable of maintaining a braking (hold) torque.

Here, the nozzle head 200 is indirectly brought into contact with a position regulating member (105) for regulating the position of the rotating member (drum 10), thereby rotating the rotating member (1).
1) and the nozzle head 200 can be positioned relative to each other in the left-right (Z1) direction in FIG. Specifically, the nozzle head 20
The contact member 205 is provided as a part of the contact position 0 and the contact member 205 (contact surface 205f) is brought into contact with the second position regulating pin 105 as shown in FIG. Therefore, the maintenance of the nozzle head 200 and the nozzle head 200 with respect to the rotating member (10) after the maintenance are performed.
Re-relative positioning can be performed quickly and accurately. Handling is extremely simple.

Since not only the nozzle head 200 but also the rotary member (10) can move in the left and right (Z2) direction, as a result, the nozzle head 20 for maintenance is required.
Since the amount of movement in the Z1 direction of 0 can be reduced, the size of the movement means 40 can be reduced. That is, the size and weight of the entire printer can be reduced.

As shown in FIG. 2B, the contact member 205 has a contact surface 205f and a second position regulating pin 105.
Is provided, a pair of inscribed surfaces 205I opposing each other in the up-down direction are provided so that the relative positioning between the rotating member (10) and the nozzle head 200 can be determined in the direction perpendicular to the drum axis X0 (vertical direction). ) And the drum radial direction [Z1 (horizontal direction)], so that the predetermined print quality can be stably maintained from this point. In particular, it is easy to make the printing accuracy constant in the column direction.

The advance / retreat table 41 is moved rightward (Z1) in FIG. 1 using the drive source 44 of the advance / retreat means 40, and the contact member 205 comes into contact with the second position regulating pin 105. Later, it is formed so that the braking (hold) torque of the drive source 44 can be maintained. Therefore, the relative positioning state, that is, the positioning accuracy can be maintained as it is at the same time as the completion of the relative positioning.

The rotating member [10 (frame 10
0)] side is also formed so as to be movable in the Z2 direction by a drive source (not shown), and is formed so as to apply a braking (hold) torque when the position restricting portion 101 contacts the position restricting pin 2.

In this way, it is very easy to remove a jam or the like. Moreover, the frame 1 for supporting the rotating member (10)
In 00, the supply roller 91, the charging roller 21, the heater 22, and the like are attached with predetermined relative positions. Therefore, if the drum 10 is brought into contact with the position regulating pin 2 to regulate the position, the printing operation is started immediately.

Further, since the rotating member (10) is also formed so as to be movable in the Z2 direction, the amount of movement in the Z1 direction during maintenance or the like of the nozzle head 200 can be reduced, and the rotating member (10) can be moved to the main body case. Since it is taken out, jam clearance and the like can be easily performed.

If the nozzle head 200 (205) and the second position regulating pin 105 are formed so as to abut on the axis X0 as shown in FIG.
The inkjet nozzles 207 for each color (C, M, Y, B) forming 0 can be easily positioned on each normal line of the drum 10.

[0042]

According to the first aspect of the present invention, a print medium is held by a rotatable rotatable member, and ink is jetted from a nozzle head onto a print medium held by the rotatable member and being rotated. Is formed so as to be printable, and the relative positioning between the rotating member and the nozzle head can be performed by directly or indirectly contacting the nozzle head with the position regulating member that regulates the position of the rotating member. The relative positioning between the rotating member and the nozzle head can be performed quickly and accurately, and the handling is very easy.

According to the second aspect of the present invention, the rotary member and the nozzle head are formed so as to be movable respectively, so that the same effects as those of the first aspect of the invention can be obtained. In this case, the amount of movement during maintenance or the like can be reduced, and the rotating member can be taken out of the main body case.

Further, according to the third aspect of the present invention, since the rotary member and the nozzle head are formed so as to be able to be relatively positioned in two orthogonal directions, the same as in the first and second aspects of the present invention. In addition to achieving the effect, it is easy to make the printing accuracy constant in the column direction of the printing medium.

Further, according to the present invention, the relative positioning state between the rotary member and the nozzle head via the position regulating member can be maintained using a power source for moving the rotary member and / or the nozzle head. , The same effects as those of the first to third aspects of the invention can be obtained, and the handling is further facilitated.

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

FIG. 2 is also a view for explaining a substantial position regulating member.

FIG. 3 is a view for explaining a modification of the contact form between the contact member and a second position regulating pin.

FIG. 4 is a diagram for explaining a previously proposed inkjet printer.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 guide rail 2 position regulating pin 10 drum (rotating member) 21 charging roller 22 heater 30 reciprocating means 31 reciprocating table 40 advance / retreat means 41 advance / retreat table 44 drive source 45 slide guide 90 medium supply means 91 one supply roller 95 one side Guide 100 Frame 101 Position regulating part 102 Position regulating pin 103 Lever 104 Hook 105 Second position regulating pin (position regulating member) 200 Nozzle head 207 Inkjet nozzle 205 Contact member 205f Contact surface 205I Inner contact surface M Print medium

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Hiroyuki Takada 570 Ohito, Oni-cho, Tagata-gun, Shizuoka Prefecture Inside the Tech Ohi Works, Inc.

Claims (4)

[Claims] A print medium is held by a rotatable rotating member, and ink is jetted from a nozzle head onto the print medium held by the rotating member and rotating to form printable characters and images. An ink jet printer, wherein a relative position between a rotating member and a nozzle head is formed by directly or indirectly contacting a nozzle head with a position regulating member that regulates a position of a member. 2. The ink jet printer according to claim 1, wherein the rotating member and the nozzle head are formed so as to be movable respectively. 3. The ink jet printer according to claim 1, wherein the rotary member and the nozzle head are formed so as to be relatively positioned in two orthogonal directions. 4. A relative positioning state between the rotary member and the nozzle head via the position regulating member using a power source for moving the rotary member and / or the nozzle head is formed. The inkjet printer according to any one of claims 1 to 3.